Hello everyone. Today I'm going to be going over four steps that's going to help you pass the CPA exam, regardless of which CPA exam review course you are using, regardless of which section you are studying for. In my opinion, as long as you follow those four steps, you should be well prepared to sit for the exam and get a pass and score. Let's go ahead and look at the first step, then I will discuss each one of them separately. The four steps are learn, review, practice, retain. I'm going to go through each step separately, explaining what tasks you should undertake each step and for what purpose and how is it going to benefit the following step. Let's go ahead and start with the learn step. Before you can review, you have to learn the material. When do you learn the material? For the CPA exam, you learn the material in college. When you take your college courses, this is when you learn the material. If you forgot what you learned, or you did not learn the material in college properly, or your college courses did not cover that topic, what do you have to do? The first step is learn. The learn step can be accomplished with farhatlectures.com. Farhat Lectures will teach you everything you need to know from zero. It's not only lectures, there are multiple choice, there are true, false, MCQs, and in some situation I have exercises. Now for the sake of illustration, I'm going to show you assuming you are studying for the FAR exam using Becker. Now I'm going to show you FAR exam using Becker. You could be studying with someone other than Becker, you could be studying for section other than FAR. Regardless, it always work the same way. Let me show you how to learn the material before you jump into the review step. So this is Farhat Lectures, which is Farhat Becker supplemental course. So this course is for FAR Becker. Now bear in mind, as I just mentioned, you can, I have courses for FAR, for example, other providers like Glyme, Surgeon, Miles, if you're studying for audit, RAG, BAR, TCP, it does not matter. Nevertheless, I'm going to show you the step for FAR Becker. So if you, once you are a member of Farhat Lectures, you have the course organized just like your CPA review course. For example, notice here, F1 Module 1 Balance Sheet, Income Statement, and Comprehensive Income. And what I have here is lessons, videos, true, false, multiple choice questions about, for example, the income statement. And this is how you will start. First, you will go with Farhat, you would learn F1 Module 1. And how do you learn it? You watch the lectures. And after you watch the lectures, I do also have quizzes. Notice here, the chapter quiz. If you click on the quiz, you have the quiz. And what's, what's the purpose of this quiz? The purpose of this quiz is to make sure you have learned the material.  But this quiz is a learning step. I do have comprehensive tests, but this is to help you test what you have learned to make sure you have learned it. So notice here, this quiz has 12 questions. So each quiz, after you answer the question, you can check the answer, make sure you, it makes sense. The answer makes sense. Then if you have any questions, you can go underneath here and do what? And for example, you would say, number one, I did not understand it, blah, blah, blah. And we'll get back to you. So this is the learning step. So again, there are quizzes, lectures, and in some, in some circumstances, you have exercises. There are two false questions as well. You would utilize all these resources to learn F1 Module 1. So once you have learned F1 Module 1, you already completed the first step, which is the learning step. Now, how, what do you do next? After you learn, now you are going to review. Let's show you what you need to do to review. Under the review step, this is when you go to your CPA review course, whether it's backer, surgeon, miles, you were blind or any other CPA review course, either at this point, since you have learned, you can view their lectures. And if you want to save time, you can view them on speed mode. You can read the book or you can do both if you have time. But the most efficient way is to read the, read the book or read the notes. Now, if you have time, you view the lectures. How do you know if step one benefited you? When you are viewing the lectures, if it makes sense, if whatever that CPA review course provider is telling you, making sense, this is easy. I understand. It means step one did work for you. Things make sense. So this is step two. Excellent. We went through step one, we went through step two. Let's look at step three. Step three, what I called is the practice step. What does practice mean? Practice is, this is when you take the multiple choice questions of your course provider. You will take the multiple choice questions of becker, roger, wily, Glyne, surgeon, miles. You will take the multiple choice. I also have comprehensive tests on my website. I'm going to go back and show you the comprehensive test. Here you are testing yourself to see if learning and review did work for you. Is it paying off? What's the goal here? The goal is at this point you should be getting 80% on your first attempt on the multiple choice questions. Now you would do multiple choice as well as simulation. Now, yes, indeed, you're getting 80%. That's great. But what's more important is the 20% that you missed and doesn't have to be 20%. Could be 25. It could be 22. It could be 15. But whatever you missed, you have to investigate every single question. Why did you miss this question? Did you miss read the question? Did you miss read the answers? If that's the case, be careful. If you don't understand why, after seeing the solution, it's a problem. So what do you have to do? Now you're going to go back and blame either your course provider or FARHAT. Why didn't they explain this for me? What did I miss? Or they explain it and I missed it. But this is where you investigate every question. So learn, review, practice. We're not done yet. The fourth step is what I called retain. Here at this point, as you're going through step one, two and three, step one, two and three, you should be taking notes about your answers you get wrong, important concept, just like taking notes. You will need to take those notes and record them on your phone, on your iPhone or Google, Android, whatever phone you have as a voice note, voice note. It means what? It means you can listen to them on the go. Some people take it on a flashcard, nothing wrong with a flashcard, except when you're driving, you cannot listen to the flashcard. When you're at the gym, if you're using the treadmill, you're running in the park, you're taking a walk, it's hard to read the flashcards. If you have the notes, you could listen to the notes, to the audio notes. So take notes per chapter, per module, whatever you have to do, and use them on the days that you are tired. For example, sometime you're going to be very tired, you don't want to start new material. Sometime you're going to be very busy where you cannot, you just, you were very tired at work, busy. You might have some personal problem.  That's fine. At least you can review what you did. And sometime you might have to travel and be disconnected from the material for a week or two. You're not. If you have those audio notes, if you're traveling on the plane, traveling on the train, having a long commute, you could also listen to them. This way you will stay connected to the material and don't get them demoralized to come back. You will stay motivated. Now let me show you some common pitfalls that students do, that that's why they get frustrated and they cannot pass the exam. One of the common pitfall is they start with step two. Yes, you can start with step two. Assuming you graduated yesterday from college, assuming you understand the material and you remember everything, you can start step two, no problems whatsoever. In the absence of that, you will need to start in step one. Some people even start in step three. And this is really, really horrible in my opinion. And some providers, they advise you to start at step three. Very bad. Practice questions and learn through that. No. Practicing questions is not to teach you. Practicing multiple choice questions is to test yourself whether you know it or not. Not to learn. You want to test yourself before getting on the exam. And those multiple choice, those valuable multiple choice, they are most valuable when you take them the first time. If you retake them the second and the third time, they lost their effect. And this is where, again, FARHAT can help. How? Let me show you. Let me show you how FARHAT can help. In addition to your multiple choice questions, I do have comprehensive tests under each module. For example, this comprehensive test has AICPA questions. This comprehensive test is non-ICPA questions. For example, here, if we go to F2, F2 module 2 EPS, I have multiple choice questions inside the course. And I also have comprehensive test at the end of each session. So I have a test, CT comprehensive test for earnings per share. One AICPA questions and one just my questions, CPA questions. So you want to use those multiple choice questions effectively. So those CTs, you want to use them during phase two. During phase two. What I mean by phase two is during practice. Use them during practice because I have multiple choice inside the course and I have comprehensive test. Take the comprehensive test during the practice stage, during the practice stage. What I do is this. I can help you. I can help you pass the exam. So if you follow these steps, if you are a member of FARHAT Lectures, you're going to go through step one. You're going to benefit through step three. And we are here to support you throughout the way. Don't hesitate to try FARHAT Lectures. There's a two-day free trial. We are always here for you. Good luck. Invest in yourself. Invest in your CPA exam and stay safe.


Hi, I'm David Vrable, I'm part of the Zen server team at Citrix and I'm going to talk about some of the work that I've done on removing one of the scalability limits inside Zen. So the limit to the number of event channels that a guest can support, basically limits the number of VMs you can support because it limits the number of front end devices that can connect to the back end. So what are event channels first? Event channels are Zen's method of doing power virtualized interrupts, they're edge triggered, they're bi-directional and that if you set up an event channel between say a front end and a back end, the front end can signal the back end and vice versa and they're also always directed at a single vCPU. So with these properties, event channels can be used to virtualize all types of interrupts, so they're used for the inter-domain interrupts for front and back ends, they're used for inter-processor interrupts IPIs, they're used for virtual lurks for things like the PV timers and the PV console, they're used for physical lurks, MSI and MSIX and they're used despite being edge triggered, they're also used for level triggered physical lurks with a bit of extra stuff. So how do they work? Well, in this example here we have domain A wants to send, if they'd have been interrupt to domain B, so first it notifies, it doesn't notify a hypercall into Zen, Zen then writes into the piece of memory shared by the target domain with Zen, so it sets something in there that says that there's an event pending, it then triggers an up call into the guest, and then the guest then looks at its shared memory and sees that there's event pending and then calls the appropriate hand for that. So the thing that limits the number of event channels you can have is the layout and structure of the shared memory. So this is the current layout, so if you look at the bottom there, that's the shared memory and we have an array of bits to say that there's an event pending, so we have 4,096 bits on that 64-bit guest, so we can have at most 4,096 events. There's also an equivalent array of masked bits that a guest uses to prevent delivery of an event, specific events. So obviously it would be inefficient to have to continually scan all 4,096 bits whenever an event turns up. So on a per-VCPU basis there's this thing called the selector word, so the 64-bit word and each bit inside the selector word corresponds to a word within the shared memory. So when you handle an event, you go through each bit in the selector word, find the first bit set, look in that corresponding word and find all the set bits in there and handle those interrupts. So what are the problems with this design? Well, the first thing is there's just too few. 4,096 is good enough for now. We support 4,000, we have the 4,096 limit within, then server and then server can only handle up to something like 300 VMs, if you want to go any more, you run out event channels. There's also no way of having any sort of event channel priority between the event channels. They're all handled with the same priority. And also because it's just a flat array of bits and you don't know when an event is going to turn up, it's also unfair and I'll have a graph later on that illustrates that a bit better. But basically the algorithm used is only to service the scoundrel bits, it's only fair if the uniform distribution of events, which turns out to be the case. We also have some additional requirements that we want for a new ABI. We would like there to be the ABI to be the same for 32-bit and 64-bit guests because it creates extra complexity within the hypervisual guests if they have different ABIs. We also want to make sure that we don't have excessive amount of memory usage because each piece of shared memory between Zen uses up a limited set of global shared mapping space within Zen. So we don't want to completely blow that away. And also we would like an ABI that could be extended in the future to perhaps even more or potentially other use cases. So this is the new Pfeiffer-based design on the right-hand side. We have the shared memory between the guest and Zen and instead of just a bit array of pending bits, we actually have an array of event words. Each word has a pending bit as before and a mass bit as before. Then it has two additional fields, the link bit, L, and the link field. And this is used to, as you can see, to construct a link list, a single link list. And it's used to create a FIFO of pending events. So you can see here that event channel one on port one was the first event that turned up and then six and then three. And then in the per-VCPU shared area, we have the head pointers, so where the head is. And because events can only be on one, effectively in one FIFO, we can insulate many lists onto the same event array. So we can have multiple heads. So in the actual implementation, we have up to 16 heads, which gives us 16 different event priorities. And then to allow the guest to see which cues have pending events, we also have a ready field, which is similar to the selected bit and the two level design. And that upset bit in that says there's some pending events on a particular cue. So one thing about using a shared memory interface is that you, most typically with a list, you synchronize the list with spin lots, obviously with a shared memory implementation between Zen and a guest, you can't do that. So this is the core algorithm we used to actually link an event. So part of raising events. Firstly, just set the event pending and we check if it's masked. If it's masked, we don't do anything because the guest is not interested at this time. And then we check if it's already in the list. And if it's already in the list, we also don't need to do anything. Then we add it to the list. And then we atomically set the link field of the tail of the list to point to our new event. Or if there isn't a tail, or rather if the tail is not currently in the list, i.e. the list is empty, then we set the head field so the guest can find a new head. And then finally we advance the tail to point to our new event. Then conversely, when we handle event, we read a local copy of head initially. So the guest keeps his own copy of the head pointer. So it never has to write back to the Zen, the shared head. So Zen only writes the head and never removes some central rates conditions. And if the last link field we read was zero, then that current local head would be zero. And we know that we previously emptied the list. So then we read the new value of the head out of the per-VCPU control block. And then we clear the link field and the linked bit. And that removed that event from the list. We advance our local copy of head to the new head, which if it is the tail of the list, this will set the head to zero. When we go back around next time around, we know to pick up the next head. And then if the event is still pending, if something else hadn't cleared it, like if the event channel is disconnected or something. And if it's not been masked, then you just call the interrupt handler. So this graph here illustrates one of the key benefits other than just having lots more. It's fairness. So by fairness, we mean the average latency of an event should be independent of its port number and independent of any other events that are occurring elsewhere. So this graph is from a very contrived test deliberately constructed to show worst case behaviour. So what we have here, and this is actually the use case that it's, or the setup that it's using, is not dissimilar to what you'd actually see in a real DOM zero, for example. So in a real DOM zero, what you typically have is you'd have a whole bunch of physical works at low event channel numbers, a whole bunch here, and then spread out to the rest of the event channel space. You'd have all the front, the event channels going to front ends. And typically what you get is you see all the physical works here would be a lot higher rate on average than the spread out of all the other events. So you'd end up with a, you wouldn't end up with a uniform distribution of events rate. So in this example here, we basically have a port 73, I think. We have an event that occurs about five or so times more often than the events in the rest of the space, the other nine events. So effectively what that means is that the algorithm that the two level based design uses always ends up scanning for bits starting from the same place, which is always after the highest rate. So the one immediately after the highest rate, so port 73, is always service first and has low latency. And then it gradually climbs up as you move away. And then finally the highest rate one has the worst latency because that's the one that's always service last. As you can see, the FIFO based design, because events are serviced in the order that they're raised, we have completely uniform average latency. So the current status of this work is the Zen support has merged as of last week, I think. Linux support, so yeah, the Zen support should be in 4.4. Linux support is done. It may make it into 3.13, but it's, I mean, it definitely will be in 3.14. And then there's still some further work in this area, not specifically to do the extended limit. Although we've added support for 16 different priorities, we don't actually make use of this feature yet heavily. We use effectively one priority for the timer interrupts in Linux, so the timer interrupt always gets serviced first and all the other events are all serviced at the default priority. So this is done just because I didn't have time to actually spend time investigating how you could effectively use priorities. For example, it might be useful to put the event channels used to signal Q and U to do MMIO as high priority because that's likely to require low latency. And you might want to put the bulk data events for things like blockback or netback at a lower priority.  One of the things that got added, because as you increase the number of event channels that a guest uses, it consumes more resources inside Xen. We want to make sure that guests can't consume too many of those resources, so there's a new hypercall, a new DOM Cato to limit the number of event channels that a guest may bind. So there's support for that in Excel, so there's new command, there's new configuration file option, max event channels that you can set to limit that, and the default is set such that any typical DOM U wouldn't hit the limit. So the default is 1023, which would be fine for almost all DOM U's except maybe driver domains. You might need to change that. But other tool stacks might want to implement that, so you might want to plumb that through to the ZAPI tool stack or libber. There's only support for guest support, we've only done Linux. So if you run a DOM 0 using some other, I think NetBSD does DOM 0 or FreeBSD, then you might want to add that to one of the BSD's. Related work, as you start increasing our event channels, we're increasingly going to hit a spinlock contention inside Zen because there's a single event channel lock per domain, and every time you send a notification to a domain, you have to take that domain's event lock, which means that for a driver domain on DOM 0, all the other domains will be contending on acquiring that event channel lock. And also there's something else I'm working on, which is just a bit of refactoring of how Linux sets up its physical errors, which is not that interesting. So there's a design document, if you want to know more, you can get to it from that link. It goes into more details and explains how it covers the complete algorithm used. So if you're implementing either in guest in another OS, you'll want to read that, which is just interesting. Any questions? So on your graph of latency fairness, I noticed that it looks like the average latency is fairer but higher in the new scheme. Do you know where that latency comes from and have you got a plan to try and get that? I believe most of it comes from, it's effectively just extra cost of having the link and effectively unlink. It's more expensive to do the complex change than a simple bunch of tests and clear bits, I think, I'd not profile there anything to tell. But we also have this thing where to support different priorities, after we handle a new event, we go back and do another exchange on the ready field to see if there's a higher priority queue pending. That might add extra cost. So you did say that the one on the left happens five times as often as the other ones, right? I forget exactly that. The test setup is that when we set it up so that we service three events at once, one of which is always at port 73 and the other two are randomly distributed throughout all the other nine ports. So it comes out as average four or five times. Is it possible that the reason it's higher is because now you're frequently surfacing number 73 before the other ones? Maybe not, never mind. I'm not quite sure I'd followed that. Never mind. So in the earlier charts, it mentioned that the DOM U kernel is what puts the event back on the free list. I'm curious how does the hypervisor allocate from the free list without having a race with the guest freeing something on the free list? Sorry. In this pseudocode, the link, you basically, you do a comp exchange and as part of that, you test to see whether, when you're putting it on, to test to see whether the tail is still on the list atomically by checking the link bit and if it clears during that comp exchange, the comp exchange will fail. Go back around again, you'll see that the link is clear and then you'll go back and say the list is empty, I need to set head and then tell the guest that there's new events pending on this queue. And similarly, when you remove, the unlink is another comp exchange that's atomically clear, both link and linked simultaneously, and then return the value that it just cleared. The design document has more pseudocode explanation of this, if you're interested. I have a question. Can you turn to the future work or to-do list? Play which? I mean the future work or to-do list, the last thing. Future work, yeah. As you said, you mentioned about the then event log scalability, so what actually does this mean? Do you mean, is there any serial contention in the existing then event log by listening to your intention? Yeah, I've done synthetic tests, I was stress testing the evention device actually to effectively remove a similar bottleneck in the evention device where there was effectively a single global lock regardless of how many users have been eventioned by how many times you'd opened it. So all QMUs, despite the fact they'd opened dev evention independently would all contend on the same event channel lock. As part of testing that, I'll need to pull up the graph. I don't know if I have Wi-Fi, probably not. If you just spam an event channel lock as part of testing, you see this really easily. Whether it's actually an issue in practice, I don't know, but I can certainly see it as we tackle some of the other contention points. So once you've tackled say the grand table locking contention, then the event channel lock contention is probably important. But I don't have any data to show that. Any other questions? So have you tried running large numbers of VMs with this? And another question, are there other impediments to doing so other than event channels? Yes, to the second part. Yes, there are other limits. I think Jonathan Davies has a talk later on. We'll go more into the general scalability of Zen. I have not actually run that many VMs, apart because my test box doesn't have enough memory, but you can basically create as many effectively loopback events or whatever you like. And so I've run 100,000 plus VMs up to the limit of numbers. But I've not run lots of VMs. I think Waste has some work as well on that. I remember he's given a... But that's a different design. I don't think my experiment counts for this. So maybe we can repeat that at some point. Yeah, sure. Yeah, this actually varies from box to next, not only the event channel, I think. More questions? No? All right. In that case, thank you.


Right at this point. We're just fishing for likes. Oh, hey Didn't see you there Brent I'm a little worried I might fall out of this. Well, don't okay.  I've been told to make this update video So let's get into it Hey, my face is up here Discoming October sometime we're deciding on a couple two other people to join us enough of 24 hour live stream These two people will see how far we can level up in wizard 101 and we want to know who would be interested Much like me in the sign submissions are open to apply. So put your submissions down below and we'll decide later Like the rest of our content. It's trash So that's why we're adding challenges to make things a little interesting if you've got any ideas put them in below So if you're interested put your name below you have to be following on twitch, but everyone is so remember to like and subscribe But I'm not saying it you were saying it. I'm not do it. I'm not saying do it Do it


Hi everybody. Welcome to Bio1B. Perhaps welcome to Cal Berkeley. For some of you, this might be your first lecture at Cal. And for others, perhaps your first course in integrative biology. So I'm the first of three lecturers as you probably are aware. During the regular semester, during the regular year, we have this course divided into three modules. And this year, ecology is going first. Followed by the evolution module with Dr. John Holzenbach and then the botany module with Dr. Bruce Baldwin. These modules can really go in any order. This is the first time that ecology has gone first in some years if it's ever gone first. So we don't have much to build on here for the ecology section in terms of our basic biological knowledge except what you bring in from your previous education. So I will occasion... I can't introduce absolutely every term and every concept as we go. I need to assume some things about your knowledge. I'll draw on your entire store of knowledge. I'll be mentioning far-flung countries or the occasional organism like an urchin. And I might just assume that either you've heard of that country or that organism or that you will tap it into Google and you will check on it. But I will try to speak slowly and clearly as possible. This course is difficult. Certainly. We don't apologize for that if it's hard, but we should apologize if it's confusing, unclear, or disorganized. Here we are, right? So they say the greatest public university in the world. So we're not going to apologize if it's hard, but it's our responsibility to make it clear for you. I'll primarily use the board just for writing terms outlining points, but really I'm focused on my slides in the presentation. And I will give you a subset of these slides as a PDF file that will go on to B-space after the lectures. One of the goals in Bio1B is to help develop you as good note-takers. That means coming to class and taking notes with an old-fashioned pen or pencil. So really try to do that. It's early in the day. It will be a struggle sometimes to keep awake, but there are going to be elements of the lectures that are not on the webcast, particularly videos I show and any comments I make during certain videos. And it's just a fact of Bio1B that the students that come to lecture perform better. They get higher grades. So try your best. Of course you're not going to make everyone. Let me just comment on a couple of other course logistical matters. I don't want to spend too much time on this. We have too many more interesting things to do. But I should point out that your book The Eighth Edition of Campbell is the one of this shade of maroon and black. And it's available at the local stores. I think Ned's is the only one stocking the book right now with such that you can use this coupon, this 10% off coupon. You can also find it at various other places, including online. The Eighth Edition is what we're using. And it behooves you to use The Eighth. I've given only the reading assignments for The Eighth on the course website. But on the PDF I just put up this morning on B Space. I do provide a conversion to the seventh edition, which some of you might carry from other courses. But they're not the same book. And I think you could get away with it, but you do yourself a small disservice by using The Old Edition. If it's okay with you, it's okay with me. I'll provide the conversions on that file on B Space. It's up there already. Make sure you get into the swing of B Space if you've never used it before by Monday. No labs next week, as Mike mentioned. You do have your discussion sections. And then a week off of discussion and lab. And the following week discussions and labs start full force. So we're easing into the semester nicely. We don't need to hit the ground running too fast here. Today I'm focused on by way of introducing what ecology is I'm really focused on the history of ecology. I tend to like to introduce topics from a historical perspective when possible. And I'm really doing that again, reaching back to look at the roots of ecology in order to give you an idea of what ecology is and what ecologists do. I didn't have much knowledge or awareness of ecology when I got to college. Partly that's because ecology has really taken off since I was in college. Ecology has been following an exponential growth curve. And there's a lot more awareness of ecology because of environmental problems that we face. But there's just an expansion within the science itself that is real that has occurred over the last many years. My high school biology classes might not have been up to snuff. That might have been part of it too. I'm not sure. But for some of you ecology will be a new field of study. And what I wanted to do today is to try to give you a sense of what it is. So we'll be looking into its roots in basic natural history observation. And we'll be looking at some examples of natural history and how it fed the ecological tradition and how natural history observation continues to feed ecology today. We'll be looking at some exemplars of that tradition, that natural history tradition. And then we'll start to approach definitions of ecology as we get into the 20th century. And we'll try to show that ecology is an integrative discipline. It integrates field work with laboratory work with theoretical and modeling work. And finally we'll draw a distinction between ecology and environmentalism with a couple of examples. Natural history. It's kind of old fashioned in some context these days. The idea of natural history. But at Berkeley it's still taken very seriously. Natural history. You can define it if you want as the study of nature in natural phenomena usually based on observation and description. We still have courses in natural history here in this department. Natural history is often dependent on very simple and patient observations of natural phenomena. Sitting in the field and watching an organism perform a certain behavior. Describing a plant in its growth in the laboratory. It's morphology and it's morphological changes through time. Natural history is not limited to the study of biological phenomena. To the study of living phenomena. If one were interested in the tides and their influence on the geology of the bay that would be a study in natural history. It encompasses the full range of natural phenomena whether physical, chemical or biological. But generally when we're using the term in biology we're speaking about a descriptive and observation based study of organisms and their relationship to the environment. We are fortunate to be living in the most diverse state in the country in terms of its biology. Here in Northern California around the bay we are very fortunate with an amazing local ecosystem in terms of its diversity and a rich history and a lot of resources for its study locally. If one were studying zooplankton or sharks or blue herons on the bay by observation and documentation of those observations whether photographic whether written or even without formal documentation at all one is conducting a natural history. But the best natural history does involve clear documentation and a careful recording of observations. In trying to elucidate the idea a little better we're going to go way back to some 30,000 32,000 years ago. K.A. here. I'll just note it now because I'll be coming back to it eventually. I'll have to erase this now. We'll be working very consistently at the interface of present time and past time at the interface of paleo and neo of the old and the new. This is just one of those cases where I should elucidate because you may not have the information at your disposal already what I mean by this idea. K.A. all I'm meaning is thousands of years. K standing for kilo and A for anum. Thousands of years. You might see me use capital M.A. mega anum millions of years. I have particular interests in paleontology and we'll be using the historical record consistently throughout the course. There you go for those in TV land. Watching at home. K.A. thousands of years. M.A. millions of years. K.A. in southern France was discovered only in the mid 90's. 1994 by spelunkers by K.A. enthusiasts. Not scientists who went into the deep recesses of one of these K.A. systems and discovered fabulous galleries of rock art on the walls of these caves. Now many sites like this were known in Europe and many sites around the world document the artistic activities of humans over tens of thousands of years in Australia and Africa. Here in these caves of western Europe you have exquisite preservation of the paintings on these walls as a result of the unique environments of those cave systems. So here at Chauvet when the cave explorers brought attention to this discovery and scientists went in they observed some paintings such as this. Panels on the walls you can get a sense of the scale from that guy's head of these horses. Something related to horses something in the family equidae you recognize them something horse like maybe zebra like something like that remember this is western Europe 30 to 32,000 years ago something in there. You not only have these panels of illustrations you have on the floor of these caves bones you have fossil bones. So you can start to interpret your paintings with reference to the bones and teeth and in some cases feces the scat the poo of these organisms. All of these things you use to reconstruct your knowledge of what these things are and what the people who painted these things were doing possibly thinking. A big panel like this you can see something like a rhinoceros here right pretty clear rhino form maybe indicating the movement the movement of the horns there elephant like forms here what are these back here behind the maybe baby elephant there what's that? It's a bear right you recognize it as a bear it's got the little ears it's got the short muzzle got the little face it's a bear darn it you recognize it because it's so well depicted it captures the features of that organism so well that it's just with these few strokes not only what kind of animal it is generally speaking but something about what it's doing this is an individual the person who painted this that's has made clear natural history observations during their lifetime there's no bear posing for this picture right they're going on their memory and their experiences of bears and these are not bears that are alive today these are a different species these are cave bears very common during this period in western Europe more vegetarian maybe than some of the big bears today but a bear nonetheless a member of the bear family what are those that were creeping up behind the baby elephant lions lions in France oh yeah maybe a subspecies of the living lion taxonomy as always is controversial the taxonomy the naming of these creatures at what level we rank them but they're clearly lions and taking everything into context it looks like they're in a hunt and you can even learn something about the behavior of these extinct populations of lions from these paintings because they're so carefully documented they don't they tend not to have big shaggy manes for example they don't have a big you know male king of the beasts lion mane maybe they didn't back then this group of lions maybe they didn't have manes in some cases it looks like the males are in the lead because the ones in the front have testicles perhaps unlike the lions today maybe the males took more of a lead in these pack hunting strategies where it tends to be a female lead strategy today you can actually learn something about the biology of these creatures as a result of the careful documentation and depiction of these organisms by these artists another point where I should just stop and it would be great to be building on the evolution section in discussing some of this but I should stop and note the structure of these names right this is just a common name that's our English name not standardized we call these things cave lions but in French they'll call them something else and in Japanese they'll call them something else we standardize our name for these organisms by using the Latin name which we italicize it's a good place to introduce this here because I'm going to talk about Linnaeus in a second Linnaeus right sorry I'm going to have to go to the board this is maybe a name you recall from a previous course Linnaeus Carolus Linnaeus he was actually born I believe he was born Linnae but he Latinized everything including his own name so we know him as Linnaeus famous for advancing a system of nomenclature the binomial system of nomenclature to bring organization to our naming of biological organisms and what he did was suggest that we use a binomen a two part name such as Ursus Speleus so that each kind of organism each species of organism would have a two part name like this comprised of a genus and a species the genus that we capitalize that goes first followed by the specific epithet that goes second that's not capitalized and if you're writing it on the board or on paper you should underline it if you're typing it you should italicize it and so if you ever see a name such as this with a capital on the first word and a lower case on the second word in italics you're probably dealing with a Latin name a formal scientific name a binomen that represents a particular species a particular kind of organism and you need to know this if nothing else by the end of bio one b just know that know that that's how you write a Latin name because you see it in the newspaper all the time that they'll capitalize both words and it just looks awkward and it looks amateurish and after getting through bio one b it's just you won't make that mistake okay so by way of introducing Linnaeus a little bit there let's look at Linnaeus' role in the history of ecology I bring up a couple of people here in part because I don't think they get the credit they deserve in the history of ecology Linnaeus' ideas were very interesting actually but it should be noted that these were what the writings we attribute to Linnaeus were not just Linnaeus' the historians have shown that many of his writings although produced under his mentorship were produced by what are something like graduate students and then their names kind of fell off the works over time and we attribute them all to Linnaeus right it's something that's been happening for a long time less and less as science continues but a very common thing in the past so we don't know who wrote the economy of nature specifically it was probably Linnaeus and one of his students in some combination but Linnaeus is the mentor in this process and this essay this brief essay on the economy of nature was translated into English and was read it can be very hard to find a copy of this essay and the other essays of relevance that Linnaeus wrote today but we have one of the best libraries in the world here in this very building where you can find some translations from the 1800's of these essays and you should go take a look for fun maybe not during the semester you're too busy but after studying some ecology you'll see just how foundational some of these ideas were of Linnaeus he spoke of an economy of nature a system of organismal relationships of checks and balances of nature that give rise to the patterns we see today and his phrase was taken up as we'll see in England by Darwin and others this idea and this phrase of economy of nature as an exemplar of the natural history tradition we can focus on a couple of individuals including Gilbert White who was very widely read his one book in particular the natural history of Selborne which went through many editions and has just been read by countless individuals since it was written in the 1700's where he wrote about the natural phenomena of his local area including for example the birds that lived in his local area where scientists were busy studying specimens in museums that were brought into museums and describing differences Gilbert White was out on the lawn watching birds and describing their activities and he knew he could distinguish certain species of birds based on their calls based on the times of migration that scientists based on museum specimens could not distinguish because they didn't have that living information about these features he documented all these things very carefully wrote them down and made contributions to science as a result of his patient field observations or here in America someone also who doesn't get much credit for his work at the end of his life Henry David Thoreau you may know Thoreau from just as a man of letters having written Walden or from political science with civil disobedience or something like this but Thoreau was also a very accomplished naturalist working in New England he was at Harvard wasn't really interested in classroom learning though focused on life in the field and observations of organisms and natural phenomena in the field more and more toward the end of his life in the last couple of years of his life he was making very important strides in a very concrete ecological framework but his journals from this time he died suddenly and his journals from this time weren't published didn't come to light until maybe 20 years ago he had no influence on the history of ecology don't get me wrong but he is a great scholar of a natural history approach of patient description of natural phenomena when I was a GSI in this course I was a graduate student here got my degree in this department and I was a GSI for this course and back then we learned that Thoreau coined the word ecology and in retrospect it's understandable that historians made that mistake to attribute to Thoreau the coining of the word ecology but in fact his handwriting was just terrible and a historian mistook the word geology in his journals for the word ecology and quite quickly it made it into the Oxford English dictionary and then into a New York Times book review and before you knew it everyone was saying oh my gosh Thoreau coined the word ecology but again it was an easy mistake to make based on Thoreau's work Thoreau he was interested in all natural phenomena but plants he was very good botanist he was very keen observer of plants he knew he would follow plants across the seasons the one that lived on so and so's yard just below the oaks before the first hill he would revisit a particular plant over the course of the seasons to check on it to check on its status and its life history it's you know it's stage of growth it's flowering times it's the time of its setting seed and he recorded all these things in great detail documenting carefully the days on which he was making the observations any contextual information of relevance and his notes were so good that scientists just recently could go back to them and look at the flowering times of these various plants in that region and compare them with the flowering times of the same species of plants today and interpret the changes in light of climatic change relying on Thoreau's careful natural history observations extracting the data from them and using it to provide insight into the role of climate in structuring plant growth over the past hundred years or more data there's a definition of data for you and just recall that data is the plural form of the word so try to say data are data they are the singular is datum right we all stumble on that once in a while but there you go Thoreau was reading Darwin but Darwin wasn't reading Thoreau no one was reading Thoreau at that time but Thoreau read Darwin and liked him quite a lot we've all heard of Charles Darwin who published his great work on the origin of species in 1859 in many ways Darwin is the most important ecologist of this era we tend to bow to the feet of Darwin Darwin the great in biology for his insights into evolution and we do so rightfully just an extraordinary body of work and based on creative insight and careful study both at home in the lab in the greenhouse and in the field on his travels and Darwin deserves a lot of credit for his role in the history of ecology this could be illustrated in many ways and I'm taking a very broad brush stroke approach to this history this is one way to think about Darwin's intellectual contribution here with his metaphor of a tangled bank and here's a quote that you can read on your time where he refers to this rich network of interactions in a tangled bank maybe something like this that he had in mind this picture here where all the organisms are interacting one with the next the plants with their roots in the soil with the earthworms moving through it and aerating that soil and providing a medium of growth for those plants with the birds hawking insects off of the branches of those plants and then defecating and returning some nitrogen to those soils which makes it into the waterways others which are taken back up by the plants this network of interactions really is what ecologists study ecologists study the interactions of organisms in relation to their environments and Darwin did this as well as anybody so soon after Darwin's great work a German named Heckel coined the word ecology here's Heckel in his younger years in the Canary Islands with a field assistant we don't think of him as a great field biologist he was an artist and a thinker but he is responsible for giving us this term he was a great coiner of terms and he derived the word ecology these two roots oikos and logos the study of the home what does he mean by home or house what does it mean to study the house habitat the study of the habitat of organisms or the place of dwelling the place of living the environment of organisms comprehensive science of the relationship of the organism to the environment quite a good definition in many ways from 1869 it's just one of his paintings there of mosses and various bryophytes he's quite a great artist let's jump to the 20th century ecology is not really taking its roots yet as a formal scientific discipline that really doesn't start happening until the 1960s but you are starting to get in the 20s positions in ecology at universities or in governmental contexts Charles Elton was a very clear thinking field ecologist from this early period here he is, he was at Oxford motorbike with a bunch of live traps to study mice setting off for the field but he did some he did very extensive work in the arctic in the far north and this is an example of a food web that he constructed based on data collected in the field food webs being a very important part of ecological science the studies of the interrelationships of organisms on the basis of their dietary habits and he opened one of his most famous books by saying ecology is a new name for a very old subject it simply means scientific natural history scientific meaning in this context systematic maybe quantitative based on not only description numerical description quantification basing our observations in counting and numbers and math bringing a more sophisticated method to our approach that could render it more scientific I'll talk more about Gauss, a Russian biologist later but just bring him in here to highlight that this pursuit is not entirely one of the field but it involves experiments in the laboratory laboratory experiments make contributions to ecology in very important ways Gauss was studying paramecia in a laboratory context with making formal experiments and deeply influencing the field we'll get to his ideas on competitive exclusion later we don't even need to do laboratory experiments or go into the field you could model systems on the computer simulation modeling and make contributions to ecological science but ecology is at its best when it integrates these approaches it's best when the models are based on empirical data from the field or from the lab and these three components field, lab and theory so let's get into more modern definitions of ecology and some that are very influential in the 60s an Australian ecologist defined ecology as the scientific study of the distribution and abundance of organisms distribution and abundance spatial distribution and abundance the numbers, how many are there or what is their density the density of organisms or the biomass how much do they all weigh, distribution and abundance it's the scientific study of the distribution and abundance but that's a little static that's a little narrow as a definition certainly doesn't encompass the full range of ecology a little bit better is a definition that you hear quite a lot in an ecology course in an undergraduate ecology course Charles Krebs it's the scientific study of the interactions that determine the distribution and abundance of organisms so you can use that as a working definition if you want you could use one of the older definitions that I've given you if you want hopefully you're getting a better sense of what ecology is let me give you an example of distribution and abundance the study of distribution and abundance is a fine little bird that lives in used to live in only in the old world in Africa there's one riding on the back of a wildebeest or something in their breeding plumage they have these nice orangey yellow plumes on the back of their heads they tend to use big mammals to follow big mammals as they move around and they pick up insects and animals as they walk as the hooves and feet disturb the ground grasshoppers and a lizard might get partially stepped on and the bird will go in and pick it up it forms this relationship with these other mammals this was an African bird and a well known African bird in the 1930s a small flock of these guys blew across the Atlantic and landed in South America an incredible dispersal event that was apparently well documented the arrival of this small flock and from that point of arrival in South America in 1937 they've expanded throughout the new world think about how that dispersal event affected the distribution and abundance of cattle egrets it affected it quite a lot across the globe in terms of their range and their overall numbers on a global scale let's take another example of distribution and abundance that's Australia and that's a kangaroo and it shows the limits of the range of these red kangaroos macropus rufus and the hotter areas here are the areas of greater density in terms of the number of kangaroos per square kilometer the limits of the range tend to correlate with what who knows the landscape there a little bit what are those limits dry areas the limits of the occupied areas are the driest areas of the continent those coastal areas are much wetter and maybe less variable in their in their aridity so for some reason the kangaroos are occupying primarily the driest areas the arid and semi arid areas why I'd like you to consider why after watching a video that I'll provide for you either at the end here today or I'll give you it as a stream online I don't want to take the time to do it right now ecology is not environmentalism the two have become so closely related that in the public's eye if you say you're an ecologist they might think that you are an environmentalist and they may be right because many ecologists as a result of their studies are led to action in a political context in terms of wanting to make changes that support a healthy environment but the two fields are not synonymous they're not equivalent ecology will speak of as the scientific study of organisms and their interrelationships environmentalism is will think of more as a socio-political movement to toward creating healthy and sustaining healthy ecosystems let's use Rachel Carson as an example of a biologist and an ecologist working in the field and studying organisms who was led by her studies to draw attention to the role of pesticides in the decline of bird populations pesticides particularly DDT at this time were causing the thinning of eggshells as a result of getting into food chains and making their way into the tissues of birds that then laid eggs the shells of these eggs were thinned to the point where they were cracking and many birds were having trouble surviving her book Silent Spring drew attention to this phenomenon and Silent Spring a reference to just how quiet it had gotten in springs that used to be rich with birdsong and this was one of the major catalysts for the environmental movement this is an ecologist who catalyzed socio-political action as a result of her scientific work so they are closely related but they're not the same thing just finishing the discussion of this early period this image alone is thought by historians to have been one of the major factors in the launching of the environmental movement when human beings saw Earth from space for the first time a spinning and fragile appearing blue planet against the dark recesses of space this image alone for many people triggered an awareness of our globe as a single and fragile home alright you guys you guys have hung in there well please try to come back on Monday have a great weekend


Hi it's me with another question and this one is what makes a permaculture design course worth two weeks of my life well that's a good question I mean it is a significant investment of time if not money to do a permaculture design course and when I did mine I suppose I was pretty interested in the topic and I read a little bit about it but the course was taking place in the house that I was living in the shared house so essentially I felt like permaculture had come to me and I had to be on the course but if I was to do it again I would say well what do you learn on a permaculture course I guess that varies to some degree depending on who you learn with and where you are certainly in Britain we have what's known as the core curriculum so the permaculture association defines a number of things that a permaculture design course should cover and if they provide the certificates then those things need to be in the course and they're obvious things for me as a permaculture designer the obvious things to do with and what is permaculture the ethics the principles design process and those kind of things and then different aspects of how you apply those in different areas like soil and water and energy and buildings and so on so all of those things are in there what kind of level of detail do you have I think one of the nice things about a design course rather than just watching a video even like this one is that you can ask questions so the course when I'm teaching one of the first things that we want to know when people come on the course or apply for the course is what is your background what do you want to get from the course what do you know and what do you want to learn because then it's easy to pitch pitch what we're teaching to the needs of the people in the room and of course there's the interactivity of questions and being able to answer those questions whilst also trying to follow a basic path that meets everybody's needs in the room so there's a potential you know on a PDC as we say to get things from the PDC if you if you come along in person rather than doing a course that's perhaps all on video because the video just tells you what the video is going to tell you so on a design course that I teach the design courses I teach are the first quarter of the course the first kind of 25% or so focuses on the basics of what is permaculture what are the ethics the principles whether they come from what is systems thinking because that for me is very important we inhabit system we are systems we inhabit bigger systems that feed us and then we output waste products into and when we're putting things together in the landscape when we're deliberately constructing systems to grow food or contain heat for instance in the building and such then those things we need to understand the relationships between things so systems thinking gives us a very important foundation if you like those things I'm also very interested in pattern and how nature uses shape to solve problems and how we do that in a very obvious way in our homes now in the sense of flat sheets very good for collecting and for distributing so radiator and a hot water heating system in a house is very much flat it has lots of surface area to give off that heat but also in the same way if you build a solar collecting panel whether you're trying to generate electricity or catch the heat of the sun into water again that panel is quite flat it has a big surface area but when you're storing water and you want to retain that heat and the tank is not flat because the tank would then lose a lot of heat so the tank uses a different shape so you bring water from the panels or your panel into a tank which is much more rounded cylindrical usually because that's a strong shape but also has low surface area so it can contain that heat and then when you want to spread that heat out you deliver it to a flat sheet again so pattern we use it throughout our world but sometimes we use it badly and so understanding pattern helps us to understand that the things we see and not always the best shape they are often there's some reason why things are a particular shape it might be because it's easier to transport for instance than it actually being a better shape for a compost bin for instance so so we look at the basics of permaculture and then we'll go into the realm of soil soil is critical because everything comes from the soil the soil is what is made by life the beginnings and endings of life make soil and provides a home for life to grow out of including ourselves that everything that we eat comes from the soil via one or two or three different stages and so how we care for soil and also how we care for water is really important and even people that come from backgrounds with the done soil science will often comment on why didn't I learn this at university because there are aspects of those things that it's more to do with the connectivity of things rather than just breaking things down into the small elements of what are the different parts of soil so we also want to know about what are the relationships and soil and how does how does soil what does soil need to be healthy and so on so then things like water so we do a chunk of time on water and how water flows what it needs how it what its qualities are what we need to do to look after it trees obviously very important as well and so we look at trees and how we can use trees in agricultural systems and for ourselves on a smaller scale we look at energy and buildings and even small a little bit on financial systems and so on and then the other key aspect of a permaculture design course is the opportunity to take that knowledge that learning and apply it to a real site so on a weekend-based course you might go away and be doing a design at home for your house or your garden or possibly even your livelihood or something if you're feeling a little bit more creative or challenged I would like to challenge yourselves and if you're doing a two-week residential then you'll be very much doing a design on the site with a real client looking at a real site with real limits and and thinking about how do you apply a permaculture in that context and by going through a process which is something that I use my book to help frame that journey we can start to look and notice the things that we didn't see that we haven't fully understood yet so I see it's a nice analogy for me as my mum likes to do jigsaws and you can't just open take the box and take off the lid and look in the box and say is it all there so she used to she for many years worked in a charity shop and they'd be given jigsaws and she would volunteer to take them home and to make them in order to find out are all the pieces there and so for me the process of doing a design helps to illuminate which are the pieces that are not there yet so we can say oh I didn't fully understand how to use zoning in this context and then we can go into okay so let's look at that again so for me permaculture design course it's I think it's a way to really kind of put permaculture together and fully understand at least at the beginning how to start to apply it in the real world and you'll still walk away from those two weeks thinking well there was a lot of stuff in there and how do I make sense of that for me but at least you'll have the basic pattern and for me it took me a little while to really focus on what is it that I really wanted to do and what was important to me and to begin with that wasn't being a teacher that took me about 10 years to get to the point where I started thinking hey maybe I should start to teach this stuff because I'm really fascinated by it but PDC I would say if you get the opportunity to do one and many people say to me it was life-changing I would certainly agree


Digital is of growing importance for us. We follow the economy realizing that areas of work that we have covered for a long time in contracts, in industrial economics, are more loss following technology. It's the important question these areas are in finance which is a big area for us too, is technology. So we are becoming more and more a digitally oriented research institution as well. We're going to start with a presentation from Toulouse's Nobel laureate Professor Jean Toulot. Digital is a priority for TSC because all industries are impacting nowadays and there are new business models and it touches on many also issues of taxes and organizations of firms and platforms. We have had a lot of talk today about platforms. This is all very important for the future of our economies and we have to think more about it and of course TSC is well-placed for that because we have been working on some of this issue for a long time but new issues surface all the time so we have to keep on being at the frontier. My kind of area of teaching and research is really trying to look inside organizations. I'm not gonna talk that much about platforms and Uber but kind of thinking a little bit more how digitization, big data, IT is changing the way organizations are set up and how they make decisions. For me what is interesting with this kind of academic conferences is really to do justice to the subtlety of this revolution which is much more subtle than in the sense what we read the media about salary employment is disappearing or like this sort of extreme views in fact it's much more subtle. Europe has had so much trouble managing to encourage and to obtain technology adoption. Why is it the case that IT hasn't really taken off as much and what are the reasons that productivity Augustans talking about how productivity is really and adoption of IT is so slow both in the US and Europe and it has to do with a couple of things that I want to touch upon. I'll discuss some of my work, some of my empirical work on this issue. There's a great deal of interesting information on the economics of organization whether firm should centralize or decentralize or also whether or not these new business models create value inside organizations or outside organizations. There's also clearly a great deal of social angst as we consider what's happening in the new sharing economy. Are workers going to be employees? Are they going to be freelancers? So there's a great deal of questions that we should use to inform policy on those issues as well. I think it was actually quite nice to hear about each other's research at a high level and sort of get you know get some conversation going even amongst ourselves. I mean it was you know diverse in terms of topics but at the same time very insightful and actually I thought there was an interesting common thread across all of them which at the end of the day is leaving flexibility to firms and letting firms explore different structures.


We're going to start off, you're going to see a lot of rapid-fire things of some extraordinary eloquent and terrific people, and we're going to start off with two who really don't need introduction, but Tariq Trotter, also known as Black Thought, The Roots, in conversation with the cultural critic, historian, journalist, writer, friend, Tore, so please welcome them. Good morning. All right, there we go, they're in the house. If art, and I want to talk about art with you today, if art is about making change happen, hip-hop definitely fits in squarely within that, since day one, hip-hop has been political, has been aggressive, at first it was very critical of Reagan, then of Bush, lightly of Clinton, but now we're in a really special era, a special challenge for the nation. It's funny, but I'm serious, we are in an ongoing national emergency, we just don't act like it every day, but hip-hop has historically been a space where folks would warn, would send out ideas around, look out for this, these are the attitudes we need to have in terms of resistance to a Reagan, a Bush and now a Trump, so is there a responsibility, is there an opportunity that rappers have in this moment to shine a light, to sound an alarm, to tell people how to respond in this moment of Trump? I feel like, and we were just talking about this, about hip-hop, I feel like that's the job of hip-hop, that's always been sort of one of the mission statements of hip-hop, is to be informative in that way, and to sort of be that sounding board, and reflect the times, and to be critical of the culture in that way, but I think what the music has evolved, in the business, has evolved into, at this point, is more pop than hip-hop, and I don't know that the responsibility of the pop artist has always been the same, I don't know if the mission of the pop artist began the same way that the mission of the hip-hop artist did. And you feel a lot of distance from that group, right? Yeah. You're like, they're not doing the same thing that... Yeah, yeah, I definitely, I feel a lot of distance, I feel like the music, the rap music, or the hip-hop music of the millennial, is, there's much about it that I don't really understand, and as I was saying, I feel like it's because it's not for me, it's not being created with my sensibility taken into consideration. Right, when we were 25, we didn't care what 45-year-old people thought, and now we're on the other side of that equation. It's true. Yeah, you know, when I was a young person, 19, 20, I didn't care what 45-year-old people thought. And that's the same thing could be said about people who created and who championed the jazz era before us. But is it just a function of age, or is the millennial rapper doing something fundamentally different that you, as a hip-hop purist, is like, no, that's not it?  Some of the folks may be receiving hip-hop through their kids, or what have you, so can you give them just an example of what you mean by hip-hop without using words?  They're mumbling, and the mumble rap thing is something that I was kind of the first person to do, but I did it in jest, you know what I mean, and I did it, you know, just for a chorus of a song where I did rap, there were like three verses, and then the chorus would be, and the name of the song was, Don't Say Nothing, so it was about not saying anything, and I feel like that has become the standard. To flip to the other direction, because I want to talk about MCing in a granular level, as I can get as a non-musician, you are in love with words, and specific words, and we were just talking about algorithm as a word that just sort of appeared to you, they're like, I want to use this, and you're trying to figure out for a week, how can I work algorithm into a rhyme? Yeah. Tell them about that. I mean, yeah, me being from that generation of the hip-hopper, the artist who was super conscious about wit and cleverness when writing a song, but yeah, sometimes a word will just come to me that I'll just set my sights on using, it's like, I don't know how I'm going to use this word, or this phrase, or this idiom, or whatever, how I'm going to make reference to it, but I'm going to, and I'm constantly working on some verse, or just putting together the lines, these words work together, these lines sort of rhyme. What did you rhyme algorithm with? Oh yeah, I had to make up a word to get me to that algorithm.  And you were focused on a sound and meaning? Yeah, yeah, for me it's as much about the flow of the syllables as it's about the word that they create. So yeah, so how I got to the algorithm line, I started, I guess talking about my origins, and I like to kind of set the tone so that my verses are vivid, like a visual sort of narrative. So I said, what did I say? I said things we've lost in the fire, the drive, the desire to perform on a higher plateau. I'm at a rap show lost in the mire, wondering how we got so far from inspired. And I say, back when photos were sepia-toned and a record player was something you would keep in your home, the night traveler, the meaning of Tariq, he was known for the exemplary performance uniquely his own, making the 21 pound for some a newfound religion. When money's put down, there's only one sound that makes OGs and young lions equally proud to listen to the secret amalgamism of algorithm. Amalgamism. How long did it take you to write that? I've been working on it like the past week or so. Is it normal, like a week for a verse? Sometimes it'll be 10 minutes for a verse or a song will write itself. But I try to always be working on something. Whenever I hear a word or I'm inspired by something that I might want to revisit later, I make it a point to write it down. So I was watching a baseball game last night to see who the Yankees are going to play in the World Series. And thank you, sir, Jesus Lord. And I could very clearly say, what are the elements that a professional baseball player must master? He's got a throw, he's got a catch, he's got a hit, he's got a run. What are the elements of an emcee that to be a great emcee, what would be a five tool or six tool, what would we be talking about? I mean, I think to be a great emcee, you have to be obviously knowledgeable of the English vocabulary. I think you need to be conscious of the quality of your craft. What do you mean the quality of your craft? Well, you need to, your craft, your skill, your level of skill should matter.    Which I feel like for some of the newer artists, that's what they pride themselves in, in being the antithesis to what we call an emcee.  You need to be able to make the English language work for you, like in that way, the amalgamism thing, you know? Some people might say, hell, you made that word up, but you kind of know what it means. And there's something to be said about a person who can make up a word. Oh, that's dope.  So I feel like these are all skills that an emcee should kind of possess.  But yeah, I mean, I think more than anything, you need to be read, be well read. And to, no, you don't need to be, you just need to be knowledgeable of words and how they fit together and knowledgeable of how to set a scene and tell a story. Is there a book that you've read that you wish all emcees would read? Yeah, the Webster Dictionary. Now wait a minute, you've read the dictionary? I mean, not cover to cover, but I mean, you know, I think. Maybe like Malcolm in prison, like Aura Park. Well, I'm a book that I think that I wish every rapper would read. Yeah, I don't know. I just wish, you know, rappers would read. When you reference breathing, I heard some giggling, but that's an extraordinarily important part of it. And circular breathing is a critical tool for rappers to be able to rap longer than a normal person would be able to talk. Right. Talk about what is circular breathing and how do you employ it? Circular breathing is is is is just that it's like rationing out. Not even circular breathing is is breathing from the diaphragm as opposed to from the chest.  And it's a technique used by orators and vocalist singers, people who sing in the opera, as well as, you know, people use public speakers. So. And what does it allow you to do?  Articulate. Without losing your breath, and it allows you to resonate sonically with everyone in the room in a different way.  Are you doing it now? No. No. Who are some orators outside of hip hop who have inspired you or helped you see, like, that's the kind of vocal artist I want to be? Famous or not famous? Oh, that's that's that's a tough one.  I had a feeling that you were going to say that. Yeah. To that question. And I didn't I didn't know quite why I thought that. But I thought you would say that a Baptist preacher. Yeah, I think there's something about the placement of the breath that is taken, you know, which we spoke about this before, too.  And yeah, when you it's like being underwater and you come up and get to take that one breath of fresh air. It's like it fuels the fire for a little bit of the way. You know what I mean? From one breath, a minister or an artist like myself is able to, you know, speak and project for many more minutes before taking another breath. So yeah, I think I was definitely inspired by by church pastors and stuff like that. When we talk about breathing, I've been thinking about pausing a lot. Right. I'm working with rock him on a book with him. And he talks about writing the rhymes out and planning where he's going to pause. Yeah. And I had never heard an emcee talk about about that. But you do you think about where you're going to pause to get the rhythmic sort of explosion that you want? Yeah, absolutely. I am, you know, if I write a verse or a song as I go over in my head, you know, I'm making mental notes of where it's best to take a breath, you know, just to to maximize, I guess, the potential of said breath. I think my favorite pause of yours. There's a line that I love and I and it's in my playlist of when I'm running because it's an upbeat song, but you say I'm a threat like alcohol, tobacco, and there's a little pause and firearms. And it totally changes where you were, where I thought you were going with the thought. And it's like, wow, like, you know, I mean, the pause makes the huge difference of it becoming two thoughts, right? Rather than just I'm a threat like the ATF like, OK, all right. That's a very simple thought. But when I thought you were going this direction, then you flip it and it's like it just explodes in the mind that much more. I agree. Is that a pause that was planned or did that come out in the studio? Um, it was it was definitely planned. Like, that's that's that's the way that I write, you know, I want, you know, there to be I want you to think that the natural progression of what what I'm saying or what I've written is one thing. And then, you know, to wow you when you realize that I intended something totally different. You know, so when when folks talk about black thought, there's generally two schools of thought. He's one of the greatest of all time. He's underrated. He should be rated higher than he is. Do you think you're one of the greatest of all time? Do you think that you are underrated? I today I think I'm one of the greatest of all time. And then, you know, sometimes I feel underrated, but when we get into ratings, like I've never seen myself underrated, you know what I'm saying? Like when people are ranking artists, ranking emcees, rappers of all time or, you know, dead or alive or whatever. I'm, you know, I'm always in that top 10. So I mean, I feel like that's not. I mean, there have been, you know, millions of millions, but there have been so many other artists to have come before I came out. And, you know, since I've been out here doing my thing, that I feel like that's a great company to sort of be in.  It's cool. You know, I'm not a fan of hip hop in that in that way. You know, it's lost. It's it's luster for you. I'm a jaded sort of artist now.  But I mean, I don't know who in your youth, you know, there's something to be said about about being introduced to something like growing up with something sure, you know, with with the arts that it always changes at some point.  And like, jazz could not continue to shock once its its lessons are taken into the culture. Rock and roll cannot continue to shock. And I think some of us are a bit surprised to get to because we thought hip hop would always be shocking. Yeah.  I'm sure they felt, you know, that it was something that would never end too. But at some point, it, you know, it always fought. I don't know. It changes. Take a step further. Because the last because the roots had an incredible man as their manager, Rich Nichols, passed away a few years ago. But he's he's an incredible brother, brilliant.  And I'm like, how could you say that? And he was like, you know, its ability to shock is gone. And that is critical to what it is. So do you agree that hip hop is dead? Hip hop, as we knew it, you know, yes, I agree. I agree with with Rich in that, you know, it's its ability to shock is gone. Is it is it is there something that could be done to bring it back?  This thing is in the suburbs. Like we got to pick up something new and move on. Well, no, you know, the sad part about what can be done and, you know, what is being done to to bring it back is just this the state of affairs, you know, the the the social political state of the world we live in and conditions. I feel like that, you know, begat hip hop in the beginning and that, you know, from that, whatever is going to be next is is is going to come. You know what I mean? It'll be it won't be there'll never be hip hop as you and I knew it in the 70s and 80s and 90s again.  I know there are things that I can do as a writer that I couldn't have done 15 or 20 years ago, things that I can convey. Are there things that you can do as an artist, as a rapper?  Yeah, you know, I feel like I'm able to tap into a far more personal, vulnerable, mortal side of myself as an artist now. Well, then I was 10 or 15 or 20 years ago. You know, I feel like it is something that is evolved over time and I feel the ways in which I present myself as an artist over time have kind of created not a demand, but, you know, almost like created a mystique where people who are into me, who are fans of the roots have kind of wanted to, you know, wanted access into a different dimension of myself as an artist, you know? So, I don't know, I feel like where before or earlier in my career, it was it was the way I wrote, especially when talking about the craft was more just presenting myself as as the all powerful, you know, almost as immortal, you know. Now I feel like it's acceptable to deal with mortality. You were in that James Brown movie that Chad was supposed to start as James Brown, which was a fantastic film. I was. And there was a great moment when James is rehearsing the band and he's like and you had to trumpet, right? Not saxophone, I was playing Pee Wee Ellis. And he's like, what are you holding? And no, it's a drum, right? You see James saw every instrument as a drum and you can hear that. And you know about that, because when you get in the pocket and you get in the rhythm, you're one of the drum, you are a drum, right? Within. So can you just convey sort of the feeling of what it's like to when you really get in the pocket and you're riding it and you're a drum within the sound, within the rhythm? I don't I don't know that I can, you know. It's a feeling that's really hard to describe. But, you know, when you're there, you know that you're there. And sometimes it's almost, you know, it's overwhelming. You know what I mean? The the you for this is just a feeling of satisfaction, a euphoric feeling of I don't know. It's hard to describe. It seems from the outside like it might be like what athletes talk about when they get in the zone and they know the basket is huge. Or yeah, yeah, whatever. It's I think it's a lot like that.  How do you practice? Your voice is killing. How do you? I'm sorry. I'm sorry. I'm sorry. I'm sorry. I'm sorry. I'm sorry. So how do you how do you practice? The better, the better. I I don't I don't really practice, you know, I practice in real time. I'm always actually recording something or actually, you know, writing for, you know, it's not really hypothetical. So if I'm rehearsing, it's for something that like I'm going to be applying that rehearsal later that day or something. I mean, but yeah, I don't I don't really rehearse that way. I have, you know, I practice for thousands of hours, but it's just something that I don't I don't do. So at this stage, you know, and I mean, just practice in general for being an MC, not for a specific.  You know what I mean? You have to keep your. So how do you do that? You have to rap. You have to do it. No, you have to do it. You don't always have to be, you know, battling someone. But, you know, friendly competition is always good. It's good to surround yourself with with other like-minded artists who you kind of respect. Yeah, you always be, you know. Always be creating this. That's that's our practice. So beyond for the next generation of MCs, for the guys who aren't. We haven't heard yet, but who are coming up with the advice, what's the direction? What do you want to see out of them?  Yeah, yeah, I know I meant you, man.   When you say fearless, that is really important. And that is a quality that you see over and over in so many MCs, what they say in, you know, how they present themselves. And I remember talking to K.R.S. one about these sort of things. And he said that a hip hop song is like a confidence sandwich in that the listener will put it literally figuratively into their mouth and repeat the words and you build the confidence that the MC had.  Do you do you are you talking about that same sort of thing?   What are some of your favorite words? I don't know, man. It's hard right now for some reason. I can't think of any any words, man. There another one up there that, like, yesterday, I had to get algorithm and I got that in. What's the next one that you've got to get in somewhere? Let me see. What have I been thinking of? I'm thinking about the word vehicular for a while. I was I fixated on the word obsidian. And I use that a couple of years ago in a freestyle. It's like, sometimes would you run that with? Oh, man, it was in the verse that I used when I was speaking at Harvard a couple of years ago. I think I rhymed obsidian with I said, black as obsidian. Black as oblivion. Black as the sky at midnight out to meridian. I'm black as a portrait with Diddy, Tupac and Biggie and black as the influence on the culture we're living in. So all I had was just so I could use the word obsidian. Oh, yeah. Yeah. What's the. Let me get one more. What's your your top five all time emcee? Top five all time emcees for me, Rock Him, Cool G Rap, Big Daddy Kane, K.R.S. One, Chuck D in that order today. In that order. No, in no particular order, no particular order. In no particular order.  You know what I mean? It's interesting that you are still prizing the folks from that earlier generation, which was a more monosyllabic, no internal rhymes, generally less complex, technically complex than the generation that you're part of, which is polysyllabic, internal rhymes, a lot of complexity. Yeah, because I feel like that's where what it is that I do and what my, you know, generation does sort of came from. So, you know, I, when people ask me who my top five, who my top ten, it's always artists who kind of made me want to do what it is that I do. The last thing, man, you are superstar on television every night. You know, you're like, yeah, the other day when I was speaking at Harvard, you know what I mean?  The Deuce? You know what I mean? I was with the Dallas Symphony and not saying these things in any, you know, way, you know, any non-humble way, but just you're living large and you came from the streets of South Philly, right? Yeah, absolutely. I mean, like, do you ever say like, damn, like I have come a long way? Yeah, I say that every day. I say that every day because I come from, you know, when I was a young person, when I was 15 years old, for instance, I didn't, you know, there wasn't much that I believed or believed in just because I, you know, I didn't have any, I didn't have a reason to. You know, if you would ask me what I saw myself doing at 25 or 30 when I was 15, I couldn't see myself, you know, still being here on this earth just because who lived to be that old? You know, I show me five people from the neighborhood who are 30 and still here. And were your parents gone at that point? Well, my father, both my parents were murder victims. Give me one second when he's heard about his father. Please. Well, both my parents were murder victims. My father, when I was super young, like before I turned two, and my mother, when I was 16 years old. So, yeah, but I'm thankful and just grateful every day because I feel like, you know, my trajectory was something totally different. Thanks, man.


Hello everyone welcome back to another session on dentistry and more today's topic is types of storage media of tooth it is associated with dental avulsion management so we know what is dental avulsion it is a complete displacement or ex-aticulation the loss of tooth from its socket due to a sports injury or accident or any other mechanical trauma so the tooth is lost from its socket so we need to keep the tooth in a storage media so what are the various storage media and its properties and its advantages and disadvantages so dental avulsion is nothing but complete displacement of a tooth from its socket in alveolar bone it's also known as ex-aticulation and it is most commonly associated with maxillary teeth or upper teeth so we may face or the kids may face trauma to the face and mouth from sports or other accidents which can cause teeth to fracture, loosen or even knocked completely out of its socket which is known as avulsion or ex-aticulation so there will be bleeding socket with missing tooth and radiographic features will be there the empty socket and a bone fracture there will be associated problem and the treatment depends upon the apical foramen closure if it is closed we can go for endodontic therapy and if it is not closed we need to wait for the closure of apical foramen so today's topic is not about the treatment today's topic is about storage media how we are going to store the tooth until it gets re-implanted so we need to re-implant the tooth back to its socket so till the time we need to store the tooth in an appropriate media otherwise the cell viability the periodontal cells which is attached to the root will be died will not be useful for further re-implantation so we need to maintain the cell viability so that's why we are keeping in an appropriate storage media so what are the storage media is available and what are the properties of the storage media so basically a storage media should have like should have anti-material properties it should be able to maintain the viability or the periodontal fibers it should favor the proliferative capacity of the cell it should have same osmolarity as that of body fluids it should not produce any antigen antibody reactions and it should reduce the risk of post implantation root resorption or even ankylosis and it should have good shelf life so these are the basic properties of a storage media that is antimicrobial characteristics should be there periodontal fibers should be maintained and same osmolarity of body fluids and it should proliferate the capacity of cells so we have various storage media that is saline tap water saliva milk HBSS that is Hanks balanced salt solution propolis contact lens solution we can use even egg white or coconut water so saline solution is osmolarity is 280 despite being compatible to the cells of PDL that is periodontal ligaments its osmolarity is 280 whereas a tap water is very unexpected storage media because it causes cell damage due to the very low osmolarity so osmolarity is very low saline solution has at least 280 the tap water's osmolarity is very low so we cannot keep our tooth in a tap water so saline has 280 so what what if we keep our tooth in tap water so the periodontal cells will be died it will not be useful anymore so saliva is a good storage media for shorter period of time its osmolarity is much lower and it is like 60 to 70 compared to the saline and it has a harming effect on bacterial contamination that is a advantage of saliva but osmolarity is comparatively low compared to saline milk is very important or a good storage media because it has amino acids carbohydrates and other vitamins so it can help the tooth like it is if it is used in the first 20 minutes after evolution there will be favorable results due to these content that is amino acid carbohydrates and vitamins and this is the most commonly used storage media that is HP SS or hanks balanced solution it is a very standard solution this solution is non-toxic biocompatible with PDL cells PHE 7.2 osmolarity is 320 so osmolarity is 320 320 is osmolarity and it does not require a refrigerator and it has a two years self-life and it is now available as a commercial product that is save a tooth so in this product name it is available so it is the most commonly used storage media we cannot say exactly commonly used but it is a most apt one save a tooth or HP SS so the next one is propolis propolis is a stickier isn't that seeps from the buds of bark of trees so it has antiseptic antibody or antibacterial or antifungal or antiviral properties conduction lens solution also we can use because it has a buffered isotonic saline solution which can preserve the PDL cells egg white also can be used as a storage media so the storage media's role is temporary because we need to re-implan the tooth with cell viability or pedodontal cells as soon as possible otherwise there will be chances of ankylosis or other problems so till the time it gets re-implaned and we need to use a storage media so most appropriate one is HP SS but sometimes won't be freely available so we can use saline or saliva which is the most easily available milk also can be used so I'll come up with a new session on dendritian merge thank you