All right, all right. So I need to share my speech. Hello, welcome everybody to Sasek's Vision series. My name is Jose Moya Diaz and today I have the pleasure of introducing our next speaker, Professor Sergei Picot from the Institute of Vision in Paris. So today Sergei will be giving a real exciting talk titled, Genetic Based Brain Machine Interface for Visual Restoration. And I will give you a brief introduction about Sergei's background. So Sergei is the director of the Paris Vision Institute since January 2021. And after a PhD in Marseille and studies in Frankfurt and the University of California in Berkeley, he returned to Strasbourg and then to Paris to launch his own team on retinal information processing, enlarging then the focus to neuro-protection. His team, for instance, revealed how an antipyletic drug is leading to retinal degeneration. More recently, the team has moved to developing strategies for restoring vision in blind patients. The work involved novel material for electrodes like graphene and diamon or even based camera for visual information processing. His team has validated the photo, photovoltaic and wireless retinal implants ex vivo and in vivo on the blind primate retina paving the way for clinical trials by the company Pixium Vision. As an alternative to retinal implants of the genetic therapy was the evaluated on rodents and primates, opening the path toward the clinical trials for the company GenSight biologics. The team of Sergei is now moving toward visual restoration at the level of the visual cortex for patients with optic neuropathies. So Sergei, thank you very much for accepting our invitation and we are really pleased that you will give a talk with us today. Hello, oh, Sergei.  But I hear you three times. So there's a delay when you were talking about... Yeah, there is a delay. There is a delay, exactly. There is a little delay because of the streaming connection, but you can now kind of share... Maybe he has opened the YouTube, so he should close it. All right, so, yes, it's ready. So, yeah. So, you can share your screen now and we can go. Can you see my screen? Yeah, yeah, perfect. I think you are in presentation mode and maybe, yeah, you should, you should open straight away from the PowerPoint. Is it okay now? No, you're not sharing at the moment, sorry. You need to share it. Yes, perfect. Okay, so, yeah, so thanks Sergei again for accepting our invitation and welcome to SAS exhibition series. Okay, sorry for the delay and slight problems. So I will now... Okay, so I will introduce the difference. I will start to present my presentation on all visual restoration. It's very disturbing because I have an echo of myself. He may have opened the YouTube, tell me. So, so, so, so probably you have the YouTube window open. So what I suggest you is that maybe you should close the YouTube window and just carry on with the Zoom presentation. Thanks. Okay, so let me introduce the strategy for restoring vision and especially the new genetic-based brain-machine interface. So I have some conflict of interest that are presented here and let me, so first I wanted to introduce the vision, the Paris Vision Institute and our interest in Paris is to prevent blindness and to restore vision.  And this will increase in time because as you see, I mean there are an increase in blind patients that should double in the next 20 years and the number of visually impaired patients should triple in this time. So this is due to aging, especially aging due to age-related macular degeneration and to glaucoma, I mean the increase in blind patients is due to this two disease. And so we want to try to see how we can prevent these disease. So the idea is that at the back of the eye, you either lose the photoreceptor and this is age-related macular degeneration or some rare disease, or you lose the written gain cells that are communicating the information to the brain and this is diabetic retinopathy or glaucoma. So at the Vision Institute, we're trying to develop therapeutic strategies. So either for complex disease, monogenetic disease, this was found on gene therapy for labor optic neuropathy or we are trying to impact on the neurodegenerative process like with the broad-derived conviviality factor as a gene-independent therapy or some kind of cell therapy using cells that are produced from stem cells and what I want to introduce today is what we do when patients are becoming blind and how can we restore some vision in these patients. So the idea of restoring vision is that if you lose photoreceptors, and you still have a written network that is still present and with the bipolar cell and especially also the gain cell, that are sending the information to the visual cortex. And different strategy for restoring vision have been developed from sub-retinal, epiretinal and optic nerve stimulation. And so I will come back, especially on the sub-retinal stimulation. But also, the idea is that when you lose the written gain cell, there are no connection from the eye to the brain. So if you want to restore some vision, you need to do it at the level of the visual cortex. And I will end on this, my talk. So the question of restoring vision is what should we do? And as you can see here on these first images is that if you have a matrix of 60 pixels, you cannot recognize faces. It's very complex, but you already can start to recognize faces with 625 pixels. And as soon as you go above 2000, it's clear that you can see the faces. So we need to restore at least several hundred pixels. And another question is the refreshing rate of these images. We know that when we watch the TV, it's a video rate of at least one image every 30 milliseconds. So this is what we should aim at. So when we have lost photoreceptors, this is the case of head-related macular degeneration. And in this case, the patient are losing the central vision where we have a central scosoma, but they keep peripheral vision. And then there's other disease, rare disease, like retinitis pigmentosa. And in retinitis pigmentosa, the patient are losing first peripheral vision. And unfortunately, they are also losing the central vision. So this patient with retinitis pigmentosa were the first patient to be included in clinical trials because they have no sight at all. And then the patient with head-related macular degeneration were then later involved if the device can provide better resolution than peripheral vision. So this was the case for this implant. So I will not introduce too much to the other implant, but this retinal implant called PRIMA was developed by Daniel Palenker at Stanford. So you can see this implant, it's non-wide at all. It's a fully independent implant. Each unit of this implant is produced by a central electrode here, a stimulating electrode. There are peripheral photodiode, infrared photodiode, and a ground grid here around each unit. And so the size of this unit, it are 100 microns. And as you can see here, you can have several of these units. And on the first clinical trials, there were 37, seven, three, seven, eight of these units. So what Daniel Palenker had shown is that if you put such an implant here above the retina of a blind right in such a recording units, you can record the ganglion cells, the spikes of the ganglion cells. And especially when you stimulate with infrared the implant, you can record these spikes into the retinal ganglion cells of the blind retina. So it's possible to reactivate the cells and especially the bipolar cell that then communicate to the retinal ganglion cell the information. Then he showed the in vivo that if he stimulates the implant with stripes, he can more or less measure the visual evoc potential and thus measure the visual equity of the animal showing that in fact the visual equity with the implant is fairly close to the visual equity of a normal animal in blue. So with this, I mean, or startup picture vision convinced Daniel Palenker to produce these implants in France. And so they were produced by the startup company and the question was, can we transfer these implant to patients? And so before we would transfer this patient to implant to these implant to patients, we decided to test them on non-human primates because the size of the cells in non-human primates are closer to the ones in patients. And also the types of cells are also very similar. So this is what we did.  And with this retina, we sliced it down in the thickness so that we could generate a blind retina. Then we would put the implant here above the retina and record the activity of the retina gain in cells with such an electrode array. So with this, we could stimulate with infrared the implant so that it would generate current in the tissue and then test whether we had spikes induced into the retina gain in cells. And the response was yes, we can record spikes into retina gain in cells. And what was very interesting was that if we attribute each of these spikes to a gain in cell, we can show that some gain in cell like this one here, this gain in cell is stimulated only by pixel 60 and not by the neighboring pixels indicating that we had a high spatial resolution with these implants because two neighboring pixels were not stimulating these gain in cells. After this ex vivo result, we went to in vivo experiment to test these implants. So what we did was to introduce the implant below the retina of non human primate. You see here the optical section of the retina. And what you can see is that the photoreceptor layers are disappearing above the implant. And this is clear here. If we label the photoreceptors at the level of the implant here in green, they disappear as compared to the neighboring area. So in fact, this area just above the implant is becoming a blind spot. And so if we generate a behavioral test where we asked the animal to watch a central spot and then present a peripheral spot asking the animal to generate a saccade toward the peripheral spots, he can generate saccade in all directions of sight except at the position of the implant because this is a blind spot. But if then we do infrared stimulation at that position we can see that the animal is no generating a visual saccade in this area. So this indicates that the animal is staying in infrared with the implant but not in visible light. This was done with spot of light that was sufficient to activate only one single unit of the implant indicating again that we have a high resolution with the implant. So this enabled us to go to clinical trials. And so the patients were implanted. You see here the implant in an area that was in fact the area, the scotum of a patient with age-related macular degeneration because they expected visual acuity was higher than the peripheral vision. And in fact, you see the patient here are wearing goggles allowing to keep peripheral natural vision. The rod here is taking images with a camera above the rod. And then at the back of this rod you have a video projector projecting an image in infrared on the implant here in the pink ellipse. So here you see that the patient is able to read letters on the movie. And in fact, in this case, the patient was tested with some goggles that were completely black so that he could not read with the peripheral natural vision. The visual acuity is close to one over 20. So it's 20 over 460 or 20 over 565. And what is also very interesting is that the patient can fuse the artificial infrared vision with the peripheral natural vision. So with this technology, so the patient can recover some useful vision, but we cannot reach cellular resolution. Each unit is of 100 micron. So it's much above the size of photoreceptors which are approximately a few microns in the very center of the retina. And we have only 378 units on the implant. So how could we improve and try to get to cellular resolution? So it's why we decided, so this is just to show you that we can reduce maybe the size of the implant, but at some point we cannot go further because the stimulating electrode will come close to the ground rate and we will not have any current getting into the tissue. So the technology that we developed to try to reach cellular resolution is optogenetic therapy. So the idea is to use protein opsin of algae because you have a photosensitive opsin in algae that are ionic channel. So the idea is to take the genetic code of these opcins to introduce them into an AV, inject the AV into the eye so that the AV would diffuse to the retina. And then neurons will start to express these opcins. So this was done first by Zalpan in Detroit. He was the first to introduce channel relapsing to into retina-gain cells. You can see the expression here in the retina of the one retina, the one mass with no photoreceptors here. And you see this expression here on the section into these gain cells. And when he shine light onto these retina-gain cells, you see that the gain cells are generating spikes during the stimulation, the light stimulation. So it's possible to restore some activity in the gain cell using this optogenetic top. So we decided to move this towards clinical trials. So we introduced not channel relapsing but catch into retina-gain cells. You see the expression in non-human primates in the peripheral ring, macular ring, simply because at the macular the neurons are pushed aside. And so if you take a piece of this retina and put it in an electrode array, you can record here on each of these electrodes the spikes of retina-gain cells. And even if you introduce some synaptic blockers in the chamber, you can record the spikes. So the spontaneous activity. And if you shine light, you see that you increase the spiking rate of the retina-gain cell and that this increase in spiking rate is correlated to the position of the transfected gain cells. We see that we have approximately one-third of gain cells that are transfected. In this case, we use catch, which is sensitive into the blue range and with a maximum at 460. So we decided to move to redshifted the opsin, catch the crimson. You see crimson is the most redshifted opsin. And we did this because we know that the blue range light is toxic and we need a high amount of light because these opsin are less sensitive than all photorecitors. And so we decided to test different vectors and we selected AV27M8 as the best vector. And the best opsin was crimson air fused with TD tomato. In fact, the fusion with TD tomato was increasing the expression of crimson. What you can see here is the recording of the retina of a non-human primate. You can see that the activated electrodes are really correlated, well correlated to the position of the moving bar. In this case, the image was slowed down four times so that you could see the moving bar. And so we have a fairly good spatial resolution because you see that the activation was really moving with the moving bar. And then if we look onto the next graph here, you see here the duration of the stimulation. And you see that with 20, 30 millisecond of stimulation, we reach almost the plateau here of the activity of the retina ganglion cell indicating that we can stimulate with images presented every 20 to 30 millisecond. So this enabled us to move to clinical trial. And so first year we also controlled that we had no immune reaction in this non-human primate because we have to realize that we are decorating retina ganglion cells as algae with the ionic channel that is in fact getting outside of the retina ganglion cell. So in order to move to clinical trials, we had to generate goggles so that there would be a camera to get visual information and then project at the back of the goggle, light at 600 nanometers, which is the peak of sensitivity for crimson. And in fact, we need those goggles because we need to normalize the light level in a high range to activate crimson. So the camera that were used are kind of special cameras that are not taking photos every 30 milliseconds, but instead each pixel is completely independent. And you see that each time the light intensity is increasing and passing a threshold, the camera is sending an event here. So you have positive and negative events here and you see the kind of visual information that are sent to the camera with the positive and negative events and then you can actualize the intensity level by measuring the light level. So this is very interesting because there's no saturation even if you watch the sun. And so you can, the patient can watch in all direction. So no, these are the results of the first patient we're seeing by optogenetic therapy. So it's maybe the type of camera we use give this kind of vibrating impression to the patient. And you see, you can find objects like this staple box. You can also count objects on the table. And so with these type of information, the patient can also detect some very light contrasted objects. As you can see here with this bottle of alcohol gel. So we have been working on other strategies like introducing some options into what we call dormant cones because in the retina, we've seen that during photoreceptor degeneration, we have some photoreceptors that remains despite they lost their auto-signal. And the idea was that inpatient, a blind patient could still have these photoreceptors and it's possible to reactivate these photoreceptors as well. And then the information processing is much better than if we reactivate ganglion cells. So now I would like to switch to the other types of visual restoration when patients are looting the ganglion cell. Is it possible to restore some vision by directly stimulating the visual cortex? So this was done in a long time ago by Brinley and Lewis and where you see they did have electrodes on the visual cortex, transistors to communicate the information and that it was possible to stimulate different electrodes and the patient would report phosphine in his visual field so indicating that there's really a correlation between the stimulation of electrodes on the visual cortex and the perception in the visual field. Unfortunately, these devices were not stable in time so there are no yet commercial device available but recently there were some new development especially here from the company's second site where you see that with electrodes at the surface of the visual cortex, it was possible to stimulate these electrodes and so that the patient could perceive shapes. But as you can see, it was done by some kind of sequential stimulation of the electrode and taking a fairly long time. So that it's not possible to use it in a very dynamic mode. To avoid this kind of long sequencing, sequence of stimulation, others have thought that as it's possible to activate with smaller current in the depths of the visual cortex, you see here that in order to either delay a saccade or elicit a saccade, if you stimulate in the depths of the visual cortex, you need less current to induce the saccade or to delay the saccade. So Peter or Selma, for instance, introduced such penetrating electrode in the visual cortex and so that it could record first where the stimulation of the electrode was generating a phosphine in the visual field and then the idea was to demonstrate that if you then shine a letter or what would be the form of a letter recorded by this, when you present a letter in the visual field, what are the electrodes that are activated on these arrays, you can then stimulate the same electrodes and try to see whether the animal can report the presentation of the letter. So here is the test. Normally, if you present a letter in the visual field, the animal can generate a saccade afterwards when you present two letters. So in some way, he's telling you, yes, I've seen the T letter in the previous. So when you stimulate the electrode that were activated when you present a letter, what was very interesting was that in this case, the animal can also report having seen the correct letter. So this indicates that stimulating in the depths of the visual cortex can generate perception. And so this was also achieved in-patient by the group of Fernandez in Spain, while he has also introduced such penetrating electrode in the visual cortex and the patient can then also report seeing letters like E, L, O, and indicating that stimulating in the depths of the visual cortex might be much more efficient. The difficulty with these penetrating electrodes is that they generate some kind of damage and that in fact, the visual perception is lost, is likely to be lost after some time because different studies have shown that there's a big reaction, glioses around the electrodes with such electrode rays. So at the Vision Institute, we have moved and tried the first optogenetic, but it was not very positive. So we have moved to another strategy which is called sonogenetic type. So what is sonogenetic therapy? The idea is that instead of using an op-syn, we are using a protein that is mechanosensitized. Take the genetic code of this protein, introduce it to an IV, inject the IV so that neurons will start to express this mechanosensitive protein. And then the idea is to generate an image, an ultrason image onto the brain which will represent in fact what is captured by the goggles. So first, yes, we can project that image because you can nicely make some image, ultrason images as it's done very often to see babies in models. So if it's possible to do images very deep into the body, it should be also possible to stimulate with images also in the brain. So this is also illustrated here. I mean, when you record the activity, the blood flow by ultrason imaging into the brain. So first, this is the classical images of MRI. And you see that functional ultrason imaging, you can have a much better image. What we've done with this kind of ultrason, fast ultrason imaging was to shine light into the visual field of a primate, record the visual activity. And you see that with either 500 millisecond or two seconds, we have similar kind of response. And we can show exactly where in fact, in the visual cortex, the neurons are activated when we present a visual stimulus in the visual field. So with this, we were able to generate retinotopic maps either to an eccentric stimulus or to an angular position. So this really clearly indicates that it's possible to do imaging in the brain. In this case, we had to remove the skull, but we can leave the jaw. So it's possible to do nice imaging. We also tested whether we could see the ocular dominance column, which were only reported in the depths of the visual cortex by autoradiography. And what you can see here is that with ultra-fast ultrason imaging, we can visualize these ocular dominance column with very good precision, even very deep here, as you can see in the visual cortex, like it was possible with autoradiography. So we have a good imaging solution with ultrason. Can we have also a good stimulation of the visual cortex? So what we did was to inject AV into the visual cortex of rats. We could see that we have a nice expression into the cortical neurons. So the idea was then, can we recall these neurons when we do ultrason stimulation, either with any cog array, as you can see here, or with a penetrating electrode into the brain? So here you can see the results with a penetrating electrode. You can see that we can measure, of course, visual response to light stimulation. But we can also recall some ultrason response if we have injected the AV previously. And you see that the latency here, which was at least 50 millisecond, is much shorter when we do direct stimulation of the visual cortex, of course, because the neurons are immediately activated. There's no need of transfer of information from the eye to the visual cortex. If we did not inject the AV, of course, ultrason are not generating any activity in the visual cortex. We can repeat the activity. You see that we can stimulate with 20 millisecond and we have a nice activation of the visual cortex. We can also stimulate with different frequency and up to 13 volts. Now, can we, so this gives us the high temporal precision of the stimulation. What about the spatial resolution? So to measure the spatial resolution, we use a cog arrays at the surface of the visual cortex with these cog arrays, we can measure visual response, which are quite classic. Then if we have no AV injected into the visual cortex, there's no response to ultrason. But if we did inject the AVs, we have nice response to ultrason stimulation. And you can see them here. And then you see that depending on the ultrason intensity, we have different types of response. And also if we move the stimulator, we can move the area of stimulation. So meaning that we have a high, we have a good spatial resolution also with this technology. And a resolution that would be highly compatible with visual restoration. Finally, the question was, do we have visual perception? So to test this, what we did was to train the animal to report light perception. And you can see that with time, so the animal can really respond efficiently to light perception. So in order to measure the response to light perception, what we do is we do the stimulation, we wait for some time and we provide water. And we see that during this period, the animal will start to leak, in fact, the tube. And you see that after four days, I mean the animal has learned that it will receive some water and start to leak the tube. Then we did a test by stimulating the visual cortex with ultrasound. And in this condition, what you can see is that the animal is leaking the tube exactly in the same way that it was doing with the visual stimulation, indicating or reporting that it perceived light during the ultrasound stimulation of the visual cortex. What was really interesting as well was that when we had the visual stimulation, the latency was almost 300 milliseconds. But if we perform the ultrasound stimulation of the visual cortex, the latency for the behavioral response of leaking the tube was more in the range of 200 milliseconds. So shorted because of course, we had no transfer of information from the eye to the visual cortex. So this was shortening the behavioral decision to leak the tube. So in conclusion, I've tried to show you that we can induce visual restoration in blind patients with age-related micro patient. The best visual acuity was with Prima. It's close to the threshold of legal blindness. The alternative solution is optogenetic therapy. And we measured that the theory for optogenetic therapy could be visual acuity close to 20 or 249 or even 20 over 72. So we still need to define in-patient what is the actual visual acuity that they can reach. It's still a non-going clinical trial. I forgot to mention that the patient included our patient with retinitis pigmentosa. And the patient you saw was blind for 14 years. And when you recovered this vision and our future project is really visual restoration at the cortical level by sonogenetic therapy. So with this, I would like to thank all my colleagues, especially Sarah Coedini, who did the sonogenetic work. Matthew did the optogenetic at the visual cortex. Greg did all the optogenetic part onto the isolated primate retina. Kevin Bled did all the imaging by faster tracin on the visual cortex. And Polori did all the tests on the implant on the human primates. And Fabrice was very helpful in all the primate studies. And this was done in partnership with colleagues like Denise Dalka, Yens Dubel, Riyad Benosman, and of course, Sose Sel who has really always put a lot of effort so that we could develop this project on visual restoration. And also the company Ecolies for faster tracin imaging, gene site for optogenetic therapy, Pixium for the prosthesis, PrimaPostasis, and our colleagues, Mikael Tanteur for sonogenetic therapy. Yannick Lema was the clinician for the studies on visual prosthesis. And also Daniel Paranker who generated the implants. And Smonberg was also very helpful for all the optogenetic therapy and a burden provided crimson. So thanks a lot. Okay, Fredette. Thanks a lot for this exciting talk. Really, really interesting. So we are now waiting for questions from the chat. So actually there is a question from Antonio Ninojosa Garcia which is asking that what are the advantage of retinal stimulation versus cortical stimulation and which one do you think is more promising? Well, for cortical stimulation it's quite complex because you need to make some intervention onto the visual cortex. So you need to open the skull. Whereas when you do some intervention onto the eye, I mean, you don't have to open the brain and so it's more accessible as well. So I think already from a kind of very simple issue of surgery, it's much more accessible. There are less risk because in the event of something is really going wrong. For a blind patient, you can remove maybe the eye. So I think the risks are less than what you would be having with a patient where you need to open the skull. Then in terms of resolution, I mean, this will be the report from patients.  The difficulty is to target the cell in all these, this, the retina, I mean, it's not easy at the moment to have some gene therapy in a very large area of the retina. And for prosthesis at the moment, the prosthesis that we are using is only two millimeter by two millimeter. We could maybe have several as I was showing on one slide, but I mean, we will see. Patient will be reporting what to see and there will be a deciding. Okay, so we are, sorry for the noise from the background. We're still waiting for questions from the, from the people that is present on the live. I just posted the Zoom link if you want to discuss more in details, these ideas with Serje. And I have a question, Serje, it's about the first part of your talk. You talk about these implants that are non-wire, you know? So what's the duration of, or the utility life of these implants? And if you can use them again or not at all? Well, the idea is first that these implants are not powered by a battery. So it's very, it's very nice because as long as they're efficient, they can stay in place. And they are powered by the light intensity activating the photo diodes. So you don't need to have a wire to the battery or anything like that. You don't need also to fill the battery. So, so this is, this is quite, easy to manage. So I think this is one first thing. Then the stability, I mean, all the tests that were done ex vivo, like accelerating testing, did show that in fact, it was, it was well, I mean, well preserved in time that it was not degrading in time. So, I mean, again, it's only when it will be impatient for 10 years or more that we will know whether at some point it is degraded and no longer active. But it has been tested for several years already and it's functioning well. Okay, and I have another question. This is more a general question about the sonogenetic therapy you've been explaining. When you started at what are your future projections with the, you know, in the midterm and how you see, you know, this therapy could reach a real and accessible impact for the whole population. I mean, it's difficult to know.  So you have to open the skull. You have to do AV injections into the brain. So you're also introducing a channel into the neurons of the brain. So there's a lot of questions there. But I think it could be useful in different neurological disease. We have to do tests. We are starting to do tests in non-human primates. And we hope to show that it's possible also maybe to, for the primate to see with this technology. And if we can show that, then why not start in clinical trials? Okay. So yes, so yes, so there is not more questions at the moment from the community. So we will be ending the stream and we can stay a bit in online, Serje, or chatting and discussing more ideas with people who wants to join us. And okay, thanks everybody who attended to this SAS exhibition meeting and see you next week. See you next time. Okay, very nice. Okay.


Hi, I'm Chris Hedges, and consortium news runs my column, which is originally published in sheer post. I'm a strong supporter of their work. They have done some of the most groundbreaking and consistent work on the persecution of Julian Assange, which is, I think, certainly for those of us who come out of the world of journalism. The most important case in terms of press freedom, they are not owned or bound by the strictures of corporate advertising, which is increasingly not true, even for left-wing sites. It's free, it's independent, it's courageous, and I can't think of many sites that I admire more than consortium news and urge you strongly to support it.


We're doing our ads at the beginning of this video. Today's show is sponsored by the Crystal Punk Kickstarter.  Backing the project will earn you a PDF or hardcover that will come with tons of new races, subclasses, magitech equipment spells and a unique class for the setting called the Evolutionist. But hey, don't take my word for it. Crystal Punk is so confident you'll love their setting that they have the Evolutionist class, a short story and several test kits available on their Kickstarter. Click the link in the description below and pledge today. Crystal Punk. It's like rock candy, but don't feed it to your grandpa. Howdy how's it going? My name's Davy Chappy and it's time to take a good look at the vicious and terrifying world of powerful, wandering monsters, child gambling and legalized dogfights. No, this isn't America's dystopian future. It's the wonderful world of Pokemon. But today, I won't be alone. We have a special guest who's an expert in most things Pokemon and D&D, a skill set that I assure you will be on full display as I read from the script that he wrote out for me when he proposed doing this video. Wow, Stuart. You look good today. Howdy, friendos. My name is Stuart. And for the past four years, I've been DMing a Pokemon campaign over on my channel called the Loading Crew. At the moment, it's the largest and most ambitious Pokemon campaign of its kind and, to my knowledge, it's the most popular. After you're done watching this video, be sure to head over to my channel where Davy and I will be talking about the best tips and tricks for running a great Pokemon campaign. Because, believe you me, just knowing how to run the system is half the battle. Running a satisfying campaign is something else. And in this video, we're going to go over a homebrew game called Pokemon Tabletop United, or PTU for short. We're going to talk about what you need to run the game, what makes PTU special and unique, and what some of the best tools are that you can use to help you run it. And you might be asking, why are we covering a homebrew system? Well, there's basically no official Pokemon campaign setting of any kind. There's Baby's First D&D game published in the 90s called Pokemon Junior, but that was discontinued after like one release. Even the Dragon Ball ZRPG lasted longer than that, and I didn't even know there was a Dragon Ball ZRPG. PTU is a system created by a group of unnamed developers, and all the materials needed are available on their website at PokemonTabletop.com. There's a handy little table with all the links you'll need to download and play the latest version of the game. The zip file contains all of the books and rules that you'll need in order to play. You might be intimidated by the amount of books and pages, but don't worry, that's what we're here for. Really, the most important PDFs are the Pokemon Tabletop United Core Book and the Pokedex, so make sure that you have them handy and nearby because you're gonna need them pretty often. The most important book, though, is the core. That'll function as your player's handbook and something of a DM's guide as well. This book seems incredibly daunting at first, but really, it's not as difficult as it seems. Unlike in D&D, where you pick a class and you level up and you are restricted by a very specific set of powers and abilities, you can pretty much pick up anything you want that you qualify for. You eventually start building arc types, and it's more like you're building a person rather than a template for an adventurer. There are classes per se, but the focus is mostly to grab the features that you want in each of them. The game is incredibly customizable and flexible, and it makes your growth as a character very organic. For example, you might start off as an ace trainer, but along your journey, you might decide that you want to pick up some cooking skills. So you take some levels in that class, and the food that you make can also buff your Pokemon during fights pretty well. Or maybe you start off as a hobbyist or a coordinator, but halfway through the campaign, you decide that it might be more fun to be a capture specialist. There's no built-in penalties for deciding to switch off.   And if that's all complicated for you, you can always just go straight fist to cuffs as a martial artist. Punch that dog, just hit it right in your face. Or you can mix and match, and while there are certain optimizations you can do, the sky's pretty much the limit here, as long as you meet the requirements to do it. A huge chunk of this book is just trainer classes, and if you're one of those people who like breaking games, this might be your ultimate playground. But that isn't the only thing. After all, what is a trainer without their Pokemon?  You can choose to do the typical fire, water, or grass rotation, or you can skim through the pokedex and pretty much pick any basic evolution that's labeled as an underdog. Sorta.  They don't even need to evolve twice, or even one time. It depends on the GM, really. Pokemon and trainers operate on similar stats. Unlike the strength, dex, or wisdom of D&D, you have HP, attack, defense, special attack, special defense, and speed. Each Pokemon has a base to those stats, and each time you level up, you add one to pretty much any stat you want. And this is where we start getting into the shortcomings of the system. There's a lot, and I mean a lot, of bookkeeping. Not only do you need to keep track of the stats and abilities of your trainer, you've got to keep track of your Pokemon. And since Nintendo's marketing department has been drilling, gotta catch them all into your head since the early 90s, you're probably gonna have not just one or three character sheets, but probably more. And if you're my players, way more. However, fear not, friends, for there are tools out there to make keeping track of your Mons easier. If you plan on playing Pokemon for any amount of time, you will absolutely want to learn how to use Roll20's character creation options. I do have a video on that. All you gotta do is make an account on Roll20, and then you go ahead and create a game and make sure that you label it as a Pokemon tabletop United Game. Boot it up, bam. You probably saved yourself hundreds of hours of work and thousands of trees. MrBeast would be proud of you. Using Roll20 not only helps you keep track of your characters, but also pretty much streamlines combat. Because each Pokemon has a different set of moves, abilities, and stats, it can sometimes be overwhelming. Instead of keeping track of all that, Roll20 lets you click a button and plop out the damage. You can also set it up so that it automatically calculates the opponent's weaknesses and resistances and other stats, but that's a video for another day. Feel free to do your own research. If you haven't used Roll20 before, you'd be surprised at what you have available to you. Also, it's completely free. There is also a companion crowdsource Excel sheet that can be used to create Pokemon and manage what skills and features your trainer has. And it's directly compatible with Roll20. You just need to export the information into a fancy... Dijon? Mustard? Oh, no, no, it's called Jason. Why did I say Dijon? Anyway, most importantly, it could be directly imported into the Roll20 sheet. It's less hassle and it's easier to level up important abilities and it's just a time saver for everybody. Buuut if you want to know some of the best practices and ways of running a Pokemon D&D campaign, head over to Stuart's channel on the Loading Crew and we'll talk about some of the best ways to run a campaign. I hope you enjoyed this collab, but yeah. Davy out.


Makusiyano is next from the next question. Yes, I'm answering a question that is puzzling many of you or many of you have been asking this question. That's all about how is gratitude calculated in Qatar? Yes, there are different types or different ways of how gratitude is being calculated. But remember, we have the official or the only way that is gazetted or by the ministry or the labor laws in Qatar. But remember, I told you most of the companies tentatively tend to divert away from what we call the original rules or what you call the rules that govern what you call the calculation of the gratitude. And what I have to let you know, the calculation of the gratitude will depend on, first of all it will depend on the number of years you've spent with that company. Then something also will depend on another factor which is what you call the basic or what you call the basic wage you sign in what you call your contract. But however, right now being that we have the normal basic pay which is for all workers in Qatar, which is 1000. We have to look at your joining date. Then you also have to look at what was your first contractor to sign with that company. For example, people of you, most of you will agree with me for most of you that have spent in the company for like around five years or six years. Remember you joined at a period where your gratitude was at, where your basic wage was at 500. Then after that it was elevated to 750. Then later it was elevated to what you call 1000. So what most companies are doing in order to run away or in order to avoid you giving you what you call or paying you according to the normal or the current basic wage which is 1000. They will go back to the normal wage, basic wage that you sign with the company when you join in the company. Let's say for example, for the first two years you worked with that company and your basic wage was 1000. So now it was 500. So meaning that they are going to first calculate those two years of your gratitude basing on the 500.  Are you getting me? Then they will come to this year when the basic wage of 1000 started so they will begin calculating the 1000 from there then probably they will add up the totals or they will add up the figure that will be your end of service bonus for the period you are going to resign from that company. However, something that I keep on telling people stop having what you call the over unspation or over anxiety for you you are thinking that I have worked with the company for five years then I have a lot of money or I have a lot of end of service bonus with that company. You may be disappointed in one way or the other because you do not know what kind of calculation this company is going to consider or is going to use to make sure that to sign what you call my end of bonus. So at the end of it all if you have a higher unspation you may end up being disappointed in one way or the other. But according to the labor laws right now and according to the official gazette all companies are supposed to calculate gratitude using what you call the basic salary of 1000 but I keep on telling you there are different companies or there are different types of companies that we have we may have those companies that are good that follow the law and we may also have those companies that do not want to follow the law in the disguise of what you call the exploiting the workers in one way or the other. So you would have to expect that at the end of it all but however this would depend on which kind of company you are working for and how many years you worked with that company. Hope I've tried to share something for you and hope I've tried to give you the clear picture of what you expect at the end of it all. So when you have a lot of higher expectations in one way or the other don't get surprised that you are disappointed in one way or the other so hope I've given you a clear picture of what you can do or what you expect at the end of it all. Thank you so much for coming back to this channel it's next from the next question by the way if it's your first time to come across this channel please consider supporting and subscribing to this channel don't forget to click that notification bell you're always notified when I upload a new video thank you so much see you again in the next video


From our studios, in the heart of Silicon Valley, Palo Alto, California, this is a CUBE Conversation. Hello and welcome to the CUBE's videos of Palo Alto, California for another CUBE Conversation, where we go in depth with thought leaders driving innovation across the tech industry. I'm your host, Peter Burris. Digital business is forcing companies to rethink what data means to them, and that means we have to rethink how we're going to manage, use, take care of our data. A lot of companies are still thinking that we can use old data practices to solve new data requirements, and that disconnect is causing tension in a lot of businesses. So how do they overcome that gap? How do they modernize their data practices and approaches to ensure that they have the options and the flexibility and the capabilities they need as they drive their businesses forward? To have that conversation, we're joined by Matt Kicksmoer, who's the Vice President of Strategy at Pure Storage. Matt, welcome back to the CUBE. Thanks so much, glad to be here. All right, let's start with the obvious. Give us a quick update on Pure. Oh, it's a super fun time at Pure right now. We just rounded our 10th birthday, so a lot of celebration going on at the company, and we're just back from our Accelerate Conference where we launched some new products and had quite a good time in Austin. Well, tell us a little bit about what was the big story from the Accelerate Conference in Austin? Well, a couple of big things. First off, we announced the GA of our Cloud Block Store product. This is where we really take the core Pure Value proposition and bring it to run natively on the public cloud. We GA it on the AWS platform, and we actually also just announced a tech preview on Azure. So that was a big part of it. That product's all about helping customers take their tier one applications and transparently move into the cloud. So I mentioned upfront this notion of an impedance mismatch, a disconnect between the requirements or the drive to use data differently, and that's a major feature of digital business transformation and traditional practices of how data storage and management is conducted. As you talk to customers, how is that challenge manifesting itself in practical as well as strategic ways? Yeah, I mean, if you look at our average customer at Pure, they're in the journey of understanding digital transformation. And it's obvious to say perhaps, but data's at the core of that. And so, let's look at, we do a lot of work, for example, in the audio industry. And you might think, okay, the auto industry, kind of a traditional space. They've been around forever, manufacturing big expensive things. But if you look at a modern car company, number one, they're a software developer. There's an amazing amount of software inside cars. And this is similar with everybody that's in digital business. They're now having to build their own software, get it to market quickly. That's a key part of their differentiation. Number two, they're increasingly IoT companies. And so they're having to learn how to harvest all this data that's coming off of their cars, bring it back to the core, analyze it, use it in real time, and use it in much post real time to design the next car and get smarter about how they do their work. And then number three, they're operating huge technology environments to run these platforms. And so they need to drive down their cost of data, their cost of goods, if you will, to be able to operate successfully and have an edge and be able to develop more. So build software faster, manage storage more efficiently, and move more rapidly and quickly? Absolutely. And then mine all that for insights and do more with that data to build the next product every year, every cycle. So what is it about the old practices that don't lend themselves to being able to be more efficient, faster, and more productive in how they deliver systems? Well, the problem with storage today is if you look at storage just as a layer within the data center, it's probably the least cloud like of any part of IT. You know, the cloud model, I don't mean cloud the destination, I mean the operating model has really been taken well to virtualization and servers and networking layer. But storage, you still have a land of lots of bespoke infrastructure, dedicated silos for each chunk of data, and a lot of manual management. And so when we talk to our typical customer, they're not doing exciting things with data, they're in the drudgery of running the factory of data down there spending all their time just keeping it working and they're horribly inefficient in terms of the infrastructure they have to use because it's so bespoke. You know, the term snowflakes is often used in the cloud world. We've just got a million snowflakes in storage. So I've always thought that, well, it's not just what I think, but there's a general recognition that every business organizes itself, institutionalizes its work, establishes value propositions around what it thinks are its core differentiating assets. And our digital business increasingly that's data. But I think what you just said sounds like that in the storage world, the assets remain the devices, they remain the lones, they remain the physical things, they remain the administrative practices. And we have to find a way to make more of that go away so we can focus more on the data that's being delivered out of the storage. Have I got that right? Absolutely. I mean, I think it's just putting data at the core of the strategy and having people actually build an architecture around it. Today, what we see is a lot of people build their data strategy piecemeal by a project, not having the opportunity to step back and just really think about it from the core. And, you know, at Pure, one of the things we talked about at Accelerate was our vision that we call the modern data experience. And this is just really rethinking the entire experience of storage, hitting the reset button and trying to ring the lessons of the cloud to how you manage data in enterprise. So let's talk about it. If we think about the modern data experience, give us a couple of kind of highlights of what are the two or three things that you absolutely must do differently? Well, the first thing is just cloud everywhere. And again, this is cloud the model, not cloud the place. And so the first thing we do is talk about the lessons of cloud with customers, standardization of services, not having bestowed infrastructure, you know, designing a set of tiers of storage and delivering that, and then really working on automation, standardization and automation so that customers can be self-service. It's easy to say, but when we go into most storage environments today, they just don't operate like this, right? It's still very bespoke. And so giving customers the tools to be able to design their storage layers, their tiers, if you will, and deliver those services in a non-demand fashion. So one of the things that we've uncovered and we talked to customers is as they try to do more exciting and advanced types of workloads in clouds and discovering that the range of data services provided by the cloud are not as robust, they're not as numerous, they're not as usable as some of the data services that you historically were able to get out of on-premise technology. Now you mentioned that you are bringing your core management infrastructure into the cloud. Are you able therefore to provide a more rich and complementary range of data services without undermining or compromising in that cloud experience? I think the key is that cloud experience that increasingly you need that cloud experience and it's not either or it's both. And so folks have realized that the cloud isn't a panacea, they can absolutely do their work on-prem with data at a lower cost and larger scale and higher performance. They can leverage the cloud for agility and what's strategic is to have that bridge that allows them to go back and forth depending on the needs of the project. And so when we say cloud everywhere, that assumes that you're going to want to use things on the cloud, in the cloud and on-prem and you need a strategic layer of technology for data that can bridge both sides. That's a key part of what we try to deliver. So as you talk to your customers, are they utilizing pure as a way of or basically the pure approach to the modern data experience as a way of getting other elements of IT and other elements of the business to think differently and to use data as the foundation for thinking about IT and digital business differently? Absolutely, I mean, I'll give you an example. One of our customers is a manufacturing customer. They run a large SAP instance. They wanted to have more agility in how they developed their SAP application. And so they use pure on-prem to host that application but they leverage our cloud block store offering to be able to do test dev in the cloud. And this allows them to easily spin up instances, copy production data to the cloud to be able to do test dev around it. And so it's brought new levels of cloud agility to what was a traditional kind of on-prem app. That's a great example. Are there any other types of things beyond just test dev that you can think about where the ability to have the certainty associated with pure and the flexibility associated with the cloud is changing the way IT is thinking? I think another big one is DR. You know, if you look at DR investments, folks don't necessarily want to have a dedicated second data center. And so being able to leverage the cloud as the DR site not only reduces the cost of DR, but that data is already there. So it then unlocks test dev and other use cases around the cloud. And so that's a big one. And we see people interested in around cloud block store. Now, pure, even before the modern data experience was one of the early talkers or early storage companies to talk about how important a multi-cloud was going to be. Absolutely. How does pure as a target facilitate the practical reality, the pragmatic reality that large enterprises are going to source cloud services from multiple different providers? Yeah, I mean, I think customers are earlier in their journey right now around cloud. So for them, it's more about hybrid cloud than multi-cloud. Multi-cloud is a place they want to get to eventually. But incumbent upon that means a standardized set of services so that storage can speak and be the same, whether it be on this cloud, on that cloud, or on-prem. And look, there's work to do on both sides of the equation, right? If you look at on-prem storage, tier one block storage, we saw that as a gap in the public clouds. That's why we brought to market cloud block store. If you look at what most people use in the public cloud, it's object storage. Well, most enterprises don't have an object store on-prem. It's one of the reasons we had an object interface to our FlashBlade product. And so this isn't just about bringing things to the public cloud, it's also about bringing some of the public cloud storage services on-prem and making sure they can connect. Obviously, pure is associated with storage devices, even though you modern date experience and what you did at Accelerate is introducing new service classes into how you're going to engage your customers and how customers can source your expertise in their business. But how is that changing pure? I think you picked up on a really interesting thing there around service classes, because one of the things, from the earliest days of pure, one of our goals was to deliver on the all-Flash data center. We obviously brought out tier one Flash products to go after the highest end, but we realized that if we wanted to be able to go after all data across the data center, you needed to be able to serve more than one class of data. And so another big push that we now said Accelerate this year was a QLC-based Flash device, the Flash Ray-C. And this allows us to really go after that second tier of larger scale and tier two application data in enterprise to be able to bring that same all-Flash cloud experience to this tier two data. So what's next? I think a big piece of that is, we just announced that, so going after that is a large piece of it. The other thing we're really working on is driving up the level of automation and intelligence within the product line. If you look at the first generation of Pure, it was all about simple, right? We have a SaaS-based management experience with Pure One and we delivered consumer simplicity to this enterprise storage landscape which was remarkably refreshing to folks. But if you look at this next generation, customers are looking for more intelligence and automation. And so the way you deliver simple to a more sophisticated customer today is open APIs, smart automation, plug-in with the orchestration frameworks they're using. And so we're doing a lot of work not only in our API level and our automation level, but also behind the scenes with our Meta AI engine to understand workload and to make intelligent decisions for the customer without them having to deal with it. Matt, I want to thank you once again for being on theCUBE. Likewise, thanks Peter. And thanks for joining us for another CUBE Conversation. I'm Peter Burris, see you next time.


Who has heard of the CAS system before? Couple hands up. We have done ancient Mesopotamia, and we've done Egypt's social hierarchy. On your notes, you see a pyramid? OK, we're going to talk about the similarities of it. And did you guys notice the signs above your desk? OK, you guys for this unit have been put in a CAS. And we're going to be playing a game. We're going to be playing Karma Corner. And we're going to understand what each of your CAS mean by the end of the lesson. This is a social structure of India and the CAS system. I like to teach interactively. And for each unit, my room is completely changed. I have bulletin boards that reflect it. And I usually incorporate them into some type of group based on the lessons. So for India, I put them into a CAS group. And there were four different tables. The signs are above their desk, so they know who they're going to be. And they'll interact together as a group for that whole unit in that particular setup. We are going to say that the Brahmins we're going to write are the priests. So in your notes, find the spark that says priest. We're in the pyramid. They're the highest ranking. OK? We're going to say that they perform rituals for the gods and only Brahmin men, though, unfortunately ladies, were the ones that were allowed to go to school. OK? So when you see in your notes, Brahmins are at the top of the pyramid, correct? Direct instruction is really important in social studies. For my subject, this is for the most part new material for students. They have never heard of Mesopotamia or the CAS system. So I have to incorporate direct instruction. All right, where are my sudras? All right, you guys are the laborers, your workers, your servants. You do not own your own business, and you don't get to own your own land. You have to work for what's that say other people. But direct instruction has to be the initial focus for most of the lessons. I'm going to show you a little clip, and it's going to be one minute. It's going to show you each of the CAS, and then you're going to have your first karma corner activity. India is a country located on the other side of the world. As a middle school teacher, and I think as an adult, there's really no way you can sit through something for 45 minutes, class after class after class. All right, so what we're going to do now, I'm going to give each group one of these sheets. And each of you are going to get your own.  First group done gets the first karma point. And they're all five of the CAS. So you are going to read through them together and tell me which CAS it is and why you guys chose that. Five minutes and be prepared to share. The students really need to move and engage in the curriculum in order to learn it. So I try and do direct instruction for maybe 15 minutes. And then they do something either individually that involves movement or as a group. Today I use a group activity that they could talk and move and work together. So I think you have to have a mix of both. And I think students are different learners. Sometimes they learn by listening with direct instruction. And a lot of them learn actively where they're engaged in it. So you have a little bit of both. You're going to have better results with them learning the material. Help them out. Help them out. Help her out. Your CAS works together. I incorporate games into quite a few of my units. When we do Ancient Greece, we divide them into city states. And they compete in different areas. We have an Olympic event that they do. All right. So keep working. You still have a minute. Those of you guys that didn't get done. They also have group challenges, who's on task, who's prepared, who's completed their homework. Did you set a goal for the test? Did everyone make their goal that they set? OK. We're wrapping it up. OK. Who's doing number one? OK. So tell us what you thought it was and why. We thought it was Bravins because Bravins go to school. And so I think it helps them socially because they're part of the team. They're working for a greater effort. It also helps them academically because they don't want to disappoint their team members. And they're stepping up their personal game so they can feel confident in their ability as well as for the team. I think they're really successful. All right. Karma points today. Going to two different groups. This group right here and also this group right here.


Let's solve a couple of questions on overlapping fringes in double slit interference. For the first one, we have a beam of light which contains blue light of wavelength lambda 1 equals 6000 angstrom and orange light of wavelength 8000 angstrom. And this produces interference patterns in a setup of the double slit experiment. The question is to figure out which of the following bright fringes overlap and you have four options right over here. Okay, before I get into this, why don't you pause the video and first try this one on your own. Alright, hopefully you have given this a shot. Now let's try and break down this question. So first of all, let us bring in the double slit experiment setup. So you have the plane, the screen and the plane of the slits. And in this one, we have a beam of light which contains blue light and orange light also. So both the blue and the orange light, they get diffracted from the two slits and they produce an interference pattern on the screen. Now there will be places where there is a bright blue fringe and there will also be places where there's a bright orange fringe. And it's a possibility that some of those fringes might overlap. And that is what our goal is. The goal is to figure out which bright fringes overlap. So let's say that there is a bright fringe at this point due to both of these lights. There is a bright fringe due to the blue light, so you get a blue bright fringe. And also there is a bright fringe due to an orange light, so you get a bright orange fringe. Now one thing that is common in these overlapping fringes is their distance from the centre. They are at the same distance from the centre, right? So if we say that the N1 order of blue fringe, this could be any number, this could be any order, 16, 12, 11, 10, we don't know. Let's say the N1 order of the blue fringe that overlaps with the N2 order of the bright orange fringe. Again, this could be any number. And the distance from the centre is the same. Distance from the centre of these overlapping fringes is the same. So that means Y1 equals Y2 if we call this distance Y just in general. So for blue light it could be Y1 and for orange light it could be Y2. This distance is the same for both. And we can further express this mathematically. We know that Y1, the distance from the centre to the N1 order of bright fringe, that would be N1 into lambda 1 into capital D divided by small d. And this is equal to N2 into lambda 2 into capital D divided by small d. Here capital D is the distance between the two planes and small d is the distance between the slits. We can see that couple of quantities get cancelled. You have these two quantities getting cancelled. So at the end what remains is N1 lambda 1, this is equal to, this is equal to N2 lambda 2. And we can write this as N1 divided by N2 and that is equal to, that is equal to lambda 2 divided by lambda 1. Now lambda 2 is 8000 angstrom and lambda 1 is 6000 angstrom. So when you work out that fraction that comes out to be equal to 4 divided by 3. So we have 8000 divided by 6000 and that is 4 by 3. Now we have a relation between N1 and N2. N1 divided by N2 must follow the ratio of 4 by 3. And we can cross check this from the options that we have. So if we look at the first option we have N1 here is 16 and N2 is 9. And 16 divided by 9 is not 4 by 3. So the first option, the first option is wrong. The second option says N1 is 16 alright and N2 is 8. So N1 divided by N2 this becomes 2 right. So this is again wrong. Second option is wrong. Third one says 12th blue fringe. So 12 divided by 10 that is, that is 6 by 5. Again it's not 4 by 3. So even this is wrong. That leads us to the last option. This is N1 that is 12 divided by N2 9. So this is 4 by 3. So this is, this is the right option. The 12th blue fringe is overlapping with the 9th orange fringe. And it's not that just these two fringes are overlapping each other. Whichever fringe that is related in this manner N1 divided by N2 is equal to 4 by 3. So even the fourth, even the fourth blue fringe must be overlapping with the third, with the third orange fringe. And if you find equivalent fractions of 4 by 3, all of those fringes would be overlapping each other. Let's move on to our next question now. For the second one we have a coherent beam of light which contains two colors. Green, light or wavelength, lambda 1, 5700 angstrom and blue of wavelength 4500 angstrom. And this is used as a source light in a double slit experiment. We also know the ratio of capital D divided by small d which is 3000. We need to figure out the least distance from the central maximum where a green dark fringe overlaps with a violet dark fringe. Okay, now the dark fringes are overlapping and we need to figure out the distance. The index of variables over here is just basically specifying that the capital D is the distance between the screen and the plane on the slits and small d is the distance between the slits. Okay, again before I get into this, try this one on your own. Alright, hopefully you have given this a shot. Now, we need to figure out the least distance from the central maximum where a green dark fringe is overlapping with a violet dark fringe. So again, if these two fringes are overlapping, then their distance from the center is the same. That is the distance that we need to find out. So let's say for green light, for green light, we can call that distance as y1 and for violet light, let's call that distance as y2. And we know that y1, y1 is equal to y1 is equal to y2. Now, at this point, we can try and recall the distance at which a dark fringe is formed. Why don't you pause the video and try to recall it? Okay, so generally, generally a dark fringe, a dark fringe of nth order could be the first dark fringe, second dark fringe, third or fourth. That is formed at a distance of n plus 1 by 2 into lambda capital D divided by small d, right? And in this case, we don't know which orders of green dark fringe and violet dark fringe are overlapping. So we can just give them a general name. We can call, we can say that the n1 order of green dark fringe overlaps the n2 order of violet dark fringe. So that distance, in that case, that distance would be n1 plus 1 by 2 into lambda 1 into capital D divided by small d. And this is equal to, this is equal to n2 plus 1 by 2 into lambda 2 into capital D divided by small d. So right away, we can see that these two quantities, they get cancelled. And now again, we can try and figure out the ratio between n1 and n2 because we already know what lambda 1 and lambda 2 are. So let's try and work that out. This would be, this would be 2n1 plus 1 divided by 2 into lambda 1 equals 2n2 plus 1 divided by 2 into lambda 2. Over here, 2 gets cancelled and this is, this is good amount of math. This is 2n plus 1 divided by 2n2 plus 1. And that is equal to lambda 2 divided by lambda 1. Now zeros get cancelled and we can further simplify this fraction. Both of these numbers are divisible by 3. So this would be, this would be 15 divided by 19. Both of these are divisible by 3. And we can write 15 as, we can write 15 as 2 into 7 plus 1, 2 into 7 plus 1. 14 plus 1, that's 15 and 19 as 2 into 9, that is 18 plus 1. Now if we compare the left hand side with this, we can see that n1, n1 is equal to 7 and n2, n2 is equal to 9. So the overlap, the overlap closest to the center maximum, the least distance closest to the center maximum happens when the seventh green dark fringe overlaps with the ninth blue, sorry your violet dark fringe. Alright, but we're not entirely done with the question now. We need to figure out what that distance is. So what we can do is we can pick any, either of these two orders and put that into either of these two equations. So let's pick n1, 7 and place that, place that over here. Place and try to figure out what y1 is basically. Even if you figure out y2, that will give us the same answer. So y1, y1 this is equal to 7 plus 1 by 2, 7 plus 1 by 2 and that is multiplied by lambda into capital D divided by small d. Luckily we have the ratio of that, that is 3000 and lambda 1, this is 5700, this is multiplied by 3000. Alright, now we can see that the answer, the units of these values, they are in millimeters. But the wavelength is in angstrom and one angstrom, one angstrom is equal to 10 to the power minus 10 meters. So maybe we can write that, we can write y1 as 7 plus 1 by 2, that is 7.5, this is multiplied by 5700 into 3000 into 10 to the power minus 10. And we will get y1 in meters, then we can change it back to millimeters to pick the right option. So first let's calculate what y1 is. This comes out to be equal to 0.0128 meters and in millimeters you can multiply this with 1000. So this will be, this will be 12.8 millimeters and that is the last option, that is option D. Alright, you can try more questions from this exercise in this lesson and if you are watching on YouTube then do check out the exercise link which is added in the description.


Welcom y toffi TV er is dim at reaction everton one full on three y Gwdysun Park o ddei disaster afternoon y Gwdysun Park it has to be said another defeat forever and I think it's one winning eight now and yeah it's it's depression it's depression. I'll be honest when I've seen the team my hope for this game dissipated you don't ever like to do that I certainly don't like to do that I like to give every player the support and the benefit of the doubt on the day but I once have seen the way we were lining up on the couple of decisions that I thought were the wrong ones before kickoff play out the way they did then that's the way it is. Neil Mawpai start and was a was a shocking decision I'm sorry I don't want to go in too much on him but that was a terrible decision when I managed it and playing golf free at right back instead of just playing practice and was a shocking decision as well from Sean Dice he's had a nightmare there and to set up in a 4-4-2 when we've been doing so much better playing 4-5-1 if you like or 4-3-3 and just he got everything wrong today everything every decision to that he needed to make today he got wrong leaving his sub so it was a bad day at the office for the man and to this defeat on him and the fact that the players just aren't good enough and they proved that today when the when the going got tough in that second half they didn't want to know and we've been beaten by a team that without being disrespectful to Fulham I don't think it is disrespectful they just look like they had nothing to play for they didn't if I'm being honest they didn't really look that interested in the opening hour until he went 2-1 up once they went 2-1 up they were excellent and he took the game away from us we threw the towel in and they comfortably won the game and deserved the win in the end but they didn't look interested to me for an hour and they've still won so fair play to them they're having a great season it's really it's difficult the game has seen flat the game is flat the fans are flat the game is flat they scored with the first attack that they had Harry Wilson the only real thing the kids got is a good shot on them and we allowed them to come inside and just have a nice tremendous shot with it he was unlucky at the post and come back and it was put in by Harrison Reedy the actor first they haven't been too slow on the rebound and then the manager made a change which was go from 4-4-2 to back to what we've been doing which was the most sensible thing I think everyone in the ground could see it wasn't working I don't know why it took them that long the thread and to make that decision it was strange I don't know why we had Joven Pickford whacking the ball up to Neil Malpie I don't know what that tactic was and we got a little bit of a grip of it we got on top Dwight McNeill scored a good goal we need to shoot more that's a fact and he done well he did a box and smashed it into the corner and then we had options to opportunities rather to win the game Neil Malpie has missed two absolute sitters sitters but you can't forgive him they're unforgivable in the position evidently in the header from Tarkovsky's knockdown has to score edit at the goalie somehow straight at him and then Tarkovsky blazes over which was as equally a badamish and then the one on one he missed after good play he done well little one two McNeill give me back just hit it just blast it lad try to dink it you know if you're not good enough to dink the ball over the keepers mate just blast it in and we've scored you know and with a with an average striker we'd have put the game to bed in that spell before halftime we should have gone in three one on the halftime de mary graiad one which just shaved the far post right on halftime and full him like i said they would just look just look like a team with nothing really to play for they've done the job that's comfortably safe they've had a good season i don't think they're gonna make your and they just looked like a team that was just enjoying playing football without they didn't have that bite we come out for the second half i mean aunt need to tell you we've had a shocker all day i don't know what they were doing in the dressing room but we were out for ages and he just allowed them and then still allowed them to warm up with the cones which was which was mad they come out for the second half edit and we're all over them again you know Paul Decision, Michael Encore with one i don't know edit and the pressure on full him in the box the ball comes in his face touch is shocking because if he'd had just got it out of his feet he could have he'd have probably scroll he could have hit the target with a heavy touch crosses the ring and get blocked for a corner that was a good chance we had corners after corner after corner which we didn't really make in that opening spell and we seem to be the team that was driving it forward now manager Bailey should have made the change then i'll assume should have been on he should have started let's be honest but that was the time to bring him on he didn't uh Damari Gray give the ball away on the half way line and then off he went Michael Encore no way to be seen he got done cross comes in bank off free now awareness behind them he was there uh balls cup back and Harry Wilson knocked him in for two one and from that moment full him from that moment on much full him deserved the victory he took over we were calamitous the players were running there was no energy he then get a third with dan james smashing it past pickford haven't asleep again and it to be honest they could have got worse pickford made a couple of shaves they missed a couple of opportunities and we really didn't look like we were gonna cause them any issues then we had a James Garn the shot that went wide in injury time that was really it we were we were just poor we were we just looked like a team that once we went behind for the second time just threw the towel in and all season i've tried to maintain that we'd be all right after Southampton and Westam I feared the worst and thought it looks that looks like that might well be it and i'd started started to make me piece of it if you can but today if we can't be we won't get an easier game than that all season for the rest for the next seven games and that's and again i'm not being if there's fallen fans i'm not being disrespectful but it's just one of them days with they just weren't really that bothered and ever they were going through the motions and everton couldn't beat them in a game everton needed the points and they didn't and we've managed to can see three goals he's got to do something with that defence got to break the defensive partnership up it's not working keens back in we're letting goals in for fun i think they're in the bottom two for defensive metrics and since he's come in and the thought he'd tighten us up and he hasn't an older top we're in the top 10 for the attack and that's got better but the thing i thought he'd do hasn't really happened and maybe it's time to put me in it now he's gave keener go it hasn't worked goals going in galore maybe it's time to change your up but i honestly feared the worst after that today i think i don't see how we survive because i think palace will be too strong for us next week i don't know but i just can't see us if we can't beat a team isn't really doesn't really look that interested how are we going to beat palace away and wolves away which we're going to have to do you know we thrown home games away we should have beat spares we didn't we should have beat these today dropping them is a different thing we should have beat on today we've had the opportunity to put this game to bed in the first hour and we haven't and we've been punished it's going to be difficult now to get out of this it really is it's not it's not over of course it isn't and you know i'm united gonna have to do some favour tomorrow and i know at the time of recording man city three in the look against lester so lester have been tanked again got out united win a forest and then it looks like a race a fight between us forest and lester and we seem born with go to spares and win you know born with who have been poor all season of one three on the run i just don't see this evidence side doing it so it's going to be a mini miracle to me now to stay up but today wasn't good enough man at the match Dwight McNeill cos he's got the call that's it from me yeah see you later


Where's this he's got a child's backpack on he kidnapped somebody sir. Did you kidnap a child sir? Where's a child? Sir, where is he?  That's your fault. It ain't no way Hello, what's your cornwood? 13 hobos 15 crack has to just get into the bus. I'm here. Shit. Okay. I'm on my way All right, you gotta you gotta hang up the phone.  Oh, yeah I mean, this is much more thorough. Give me much more thorough Because I mean just running around lights That's not what yeah, but I mean it was an emergency. Let's see emergency. I had to I mean I was teaching What are you teaching me how we're driving the wrong way to follow the damn law, Andrews We're breaking all of them. It is going against right now.   I'm like, Mr. Andrews You should know better.  You're fired That's how that's gonna go. Okay.  Yeah, it's bad Andrews It's been here actually here, you know, I've been I want you to drive a little bit. No, it's terrible You got to get used to it. It's part of your training.   Andrews All that door that door was loose, huh? He's a new recruit.  Yeah.  Thank you being good Samaritans. Remember both the corner of a mayor left the door open cornwood It's all part of your training Andrews.  It's funny how that works, isn't it? It's you call it reminds me of old times Andrews just like old times One of us is flying out of a damn car and the other one's doing his job, right? You didn't do anything. What do you mean? I didn't crash It was literally right when it might turn my head. I was like, wait, what? Anyway, I was trying to turn my sirens on and I hit the door handle by accident You know that the switch for the sirens on the complete opposite side of the door handle, right?   Just barrel in through.  Why is your car looking like this? What's what's going on? What is your story, sir? It was a very urgent delivery and It's with a little bit of a pickup on the way to Polito. This looks like a heart attack not a hiccup Do you have any idea on you sir? I do I do. All right, mr. Oscar Buster have you ever been pulled over before got any citations warnings. It's my first time Look more on unless you want to end up in jail.        I'll be a good partner. Mr. Cornwood.  Okay, that's a lot of swearing man. Give me your license put your name put your name inside What is your rights right here mr. Chatterbox Silent anything we say Ken will be used against it's gonna clown code a lot If you cannot afford a cupcake want to be provided to us fresh from the fun house Nobody's talking to you Yes, please do I Think they've murdered about 50 people Shit then you Yeah They're on them Keep calm keep tell us the locations damn an inch close the main door my door Joey give us comms turn turn sermons out turn sermons up Joe you gotta give us comms, baby I'm gonna get on foot the lake right now. Well, I don't wait. We're actually behind buildings. We're behind houses I'm not sure what you're on there. There's no way Something yeah, you know he ran away. He could be in any building copy.  Me corn got real police work to do you gonna get there. Yeah, let's go get some food to get this car fixed, right? We're getting sued today. We're gonna end up on YouTube or something. You're not gonna end up on the YouTube It's not a good thing when costs end up on YouTube. Mr.  I don't Do not Do that was so funny that that was legit like one of the funniest never happened a hundred percent on YouTube That is that one is anybody at that clip. I don't know maybe just last week You over there trying to run and gonna come down.  That was probably all YouTube too We do this okay Yeah, it's a pretty damn good day, wasn't it though? Was it a good day? Mr. Cornwood lost us.   It was good times I'm out. Hell. I miss those times. I do same. That's the thing of the past mr. Cornwood We just got to look forward to the future try to make the best of it.  Yes, sir Why is this he's got a child's backpack on he kidnapped somebody sir. Did you kidnap a child sir? Where is he sir? Where's the child? Sir, where is he?  That's your fault.   Cornwood and it's all your fault every last one of them Andrews How's that my fault? What do you mean how about your fault?  Oh, he's running out of the back right now He's got two other people with them. Uh one the the same clown that was in the car Right next to city hall. I think you ran out. I thought you were getting the car.  Thank you.  What did I do asshole?  But turn around. There is here. We see. Hey, we see the other one. He's right next to city hall And turn right next to the sheriff's office right here chatterbox himself ain't here He was here, but but he's he's around here somewhere. He's got to be between these houses, right? See I saw filling a back leave a fallen, but it wasn't him.  Can't believe you lost them, man. Do you even know what we're chasing? I do know you're chasing you chasing the clown and obviously i'm looking at it right now. Hey, what's there? Hey, what's the clown's name clown do? Doesn't matter what he did we're chasing him and you can't even matter where he did Hey, you can't even catch him.    I didn't know he was there. You hit me.  I did not. I did not trip.   I'll have you know I am the highest ranking officer inside this vehicle right now Mr. Cornwood, we are the same rank better fact. You don't even have the right uniform on you are wearing a uniform of a dead department that does not exist If anything I'm the police officer here with the higher rank because I'm in proper uniform Bcso is gonna be fine. We'll be fine What do we do if it's cornwood? You know what I like to do sometimes though I'll tell you look at some of these locals I mean this might be profiling but some of these some of these locals are really aggressive You can tell by looking at them. Which one the rest of them So that's borderline. I mean the next thing that you say could be profiling. I mean they The certain certain models Are we talking about models of vehicles or models of people?  Are you profiling? What about him makes him aggressive? What are you seeing? Does he look a specific way?   Oh, okay. Just make sure you guys are okay. We might need help It wouldn't let me in the car. Dude. I was literally getting shot from every angle This is a hundred percent your fault all of this They all jumped at me


When pain knocks at your door, what I've learned and I'm learning is you have to let it in because if you don't, it doesn't go away. Pain knocks louder and louder because pain is like a traveling professor looking for students and scholars that want to discover its secrets. And I know letting pain into our lives seems counterintuitive and a crazy thing to say to you and I've been there with that thinking. In the last few years of my life, I've realized that to let pain in, to get across that initial fear of pain, stepping across the threshold into our lives for us to wrestle with it is the only way that pain stops calling. So if pain is knocking at your door today, I want to encourage you to invite it in, sit with it, ask this teacher to teach you what it's come to teach you, then open the door and ask it to kindly leave and then choose happiness and strength and progress because of what that pain taught you during its visit. I hope that helps you guys sending much love and prayers to you today, especially if you're battling something painful in your life.