Welcome to this lecture on Transition Metal Organometallics in Catalysis and Biology. We have been talking about olefin metathesis, particularly catalysis development aspects in the last few lectures and we have focused on alkene metathesis to begin with and what we had seen in the last few lectures that both sterics and electronics they play a powerful role in modulating the catalyst activity particularly in making catalyst more efficient in their catalytic processes. So, in that regard we had seen how putting more bulky ligands on the metal help facilitated better activity for grubs catalyst by allowing phosphine dissociation and further incorporation of very good sigma donating ligands on the metal facilitated olefin binding which both together help facilitated this metathesis reaction. So, this quite a bit of which organometallic chemistry particularly with regard to the metal ligand binding as well as metal ligand pi bactonation all of those interaction played a crucial role in the evolution of olefin metathesis catalyst which went on to become better with the discovery of second generation catalyst as opposed to the grubs first generation catalyst. We had also discussed about Harman's work on the comparison of grubs first generation and second generation catalyst in the ring opening metathesis polymerization of cycloctene and that definitely proved that indeed the second generation catalyst bearing NH2C carbene were more superior in terms of fastness to produce the product than the corresponding grubs first generation catalyst. So, with this behind us today we are going to sort of look at the key points of this catalyst as we proceed in today's lecture and these are particularly with respect to alkene metathesis that we are talking about. So, this metal carbene moiety acts as the active center in catalyst. Second thing that of the various metals which could stabilize a metal carbene moiety the metals of choice for metathesis reactions where molybdenum, tungsten, rhenium and ruthenium and ruthenium are the metal of choice for metathesis reaction. The earlier times the catalyst were derived from transient metal halide as is shown over here and carbon ion donors, tungsten hexachloride plus dimethyl aluminium chloride would give tetrachlorotimethyl that in presence of ethanol would eliminate water to give tungsten oxo dichloride with this intermediate transition state giving ClWCl oxo carbene plus methane. So, this is another way of generating tungsten oxo carbene complexes. Now, in this regard we should mention that some of the earlier molybdenum version that we had seen where of molybdenum imido carbene of similar or related formulation. So, the way this particular complex which was prepared from the halide and this dimethyl aluminium chloride resulting in the tungsten oxo carbene complex. So, along the same line the Schrock had synthesized the corresponding imido carbene complex as is shown over here. So, oxo complex was synthesized much later in 1990 and when this is imido molybdenum complex methyl CF3. So, this is a very complicated complex which has both the imido and the carbene complex and also has this CF3 methyl moieties around the alko oxides. So, this is kind of a complex however this was found to be highly active catalyst but poor functional group tolerant but poor then the next important thing is while increasing the electron withdrawing nature of R the catalyst catalytic activity increases the catalytic activity increased with increasing electron withdrawing nature of R and this can be seen why the CF3 groups were put in place. Another important feature of this complex is the sterically demanding olefins even sterically demanding olefin tri and tetrasubstituted tri and tetrasubstituted olefins can undergo matrices. So, this is a very interesting development where this molybdenum imido carbene as prepared by Schrock went on to become an extremely high active catalyst then the catalytic activity could be increased by putting electron withdrawing groups and also can be because of higher activity it can be used for slow reacting tri and tetrasubstituted olefins. The only drawback to this highly active molybdenum catalyst is that they are not very functional group tolerant or the catalyst would easily be poisoned by different functional groups in the olefin. So, these are supposed to be the limitation of this catalyst molybdenum catalyst. Now, we had seen this tungsten oxo carbene complex which was synthesized from tungsten oxalide then we have seen Schrock's molybdenum imido carbene complex and now we are going to go and look at Grubb's phosphine carbene complex Grubb's complex and this was synthesized much later 1995 about 5 years later than that of the Schrock's which was synthesized in 1990 and this angle between these two halide was 167 degrees. Now the main feature of this ruthenium compound is that these are functional group tolerant like and it could tolerate groups like CO, OH, NH2, NH2, Mido and that the catalyst would not get poisoned by the presence of this group in the olefin and hence this was supposedly a very big attribute for this ruthenium carbene complex. The other important features included selectivity towards sterically unhindered olefins and strained olefins and the third thing is that tri and tetra substituted olefins cannot undergo metathesis tri tetra substituted olefins did not undergo metathesis. The point to note is the following now when one compares Grubb's complex with that of the Schrock's complex as discussed earlier one major difference is that this is exactly opposite to that of the Grubb's complex in terms of being functional group tolerant whereas Grubb's compound which was a molybdenum was highly reactive towards functional group and intolerant and hence the catalyst would get poisoned in presence of various functional group like CO, OH, NH2 whereas the Grubb's ruthenium complex is exactly the opposite and that it does not get affected by the presence of other functional group and hence the catalyst would survive the presence of other functionality and would effectively carry out the catalyst. Another important difference is that the Schrock's catalyst being highly reactive could carry out metathesis of tri and tetra substituted olefins whereas the Grubb's one is exactly the opposite and it did not facilitate or did not allow the metathesis reactions with tri and tetra substituted olefins. Third thing the third difference is obviously the ruthenium carbene is more air stable whereas the Schrock's molybdenum carbene is more sensitive to air and moisture. Lastly, the fourth difference is that ruthenium carbene has only one kind of multiple bond whereas the Schrock's complex has two kind of multiple bonding one between molybdenum and carbene and the other between molybdenum and immoidomoity. Another interesting thing is that even though they are completely complementary to each other together they made a very good set of catalysts combination where every type of metathesis reactions could be facilitated. One important thing as I was talking about this co-ordinative and electronic saturation and saturation is a very important factor in guiding catalyst activity and in this regard both the Schrock Grubb's catalysts have a low co-ordination number and these primarily we had discussed by arising from phosphine dissociation in Grubbs catalyst in Grubbs catalyst low co-ordination number. This is very important in order to facilitate alkene attack on central metal atom or this is called alkene binding. So the point to note is this low co-ordination number very is important for alkene binding and that has been achieved by phosphine dissociation in presence of Grubbs catalyst and another advantage of olefin metathesis reaction is the fact that olefin metathesis can be carried out both under homogeneous conditions as well as heterogeneous catalysis conditions and as preferred by industry most of the industrial processes utilizes heterogeneous catalyst till date industrial processes utilizes heterogeneous catalyst so whereas the laboratory applications are mostly used laboratory applications and towards this development a lot of different kinds of catalysts using ruthenium molybdenum and other metals were synthesized and as we had seen that the activity of Grubbs catalyst was improved by replacing phosphines with NHCs and so on and so forth and several types of or several variants of Grubbs catalyst were developed and they were later characterized as first generation and second generation type of catalyst and in this regard the notable few catalysts which are by far the best in terms of the activity are shown over here the variants of Grubbs catalyst that are that show great activity to start with is the this is the first Grubbs catalyst then can the carbene substituted Grubbs catalyst followed by liminosol based Grubbs catalyst followed by the B-scardene based Grubbs catalyst so what we see over here is that a significant improvement of Grubbs catalyst happens as phosphines get replaced by NHCs to becoming that with 2 NHCs where both phosphines have been replaced with NHCs and the activity keeps getting better so with this we come to the conclusion of today's lecture in which we have looked into various types of catalysts that have been developed starting with the tungsten based carbene complexes to that of molybdenum to that of ruthenium and what we saw that between Stokes molybdenum and Grubbs ruthenium catalyst there is a presence of complementarity in terms of the Stokes molybdenum catalyst being extremely sensitive to air and moisture whereas Grubbs ruthenium catalyst is stable to air and moisture Stokes molybdenum catalyst is highly reactive and hence functional group intolerant whereas Grubbs ruthenium catalyst is functional group tolerant Stokes molybdenum catalyst is good for the reactions of tri and tetrasubstituted bulky olefinic substrates whereas the Grubbs ruthenium catalyst extremely actually does not undergo any reaction with the sterically demanding tri and tetrasubstituted olefins so there exists huge complementarity between these two catalysts but the end the appreciation of for metathesis reaction is more possible because of the synthesis of Grubbs catalyst which is sort of virtually took out this metathesis chemistry out of the glove box to be able to successfully practiced in open air now one thing which is important over here that for this metathesis reaction olefin binding is a crucial step and that is facilitated by a low coordination number of the catalyst and this is achieved by phosphine dissociation giving rise to low coordinated metal species for both Schrock and Grubbs catalyst which can then finally bind olefin giving metathesis reaction so apart from this industrial processes prefer heterogeneous catalyst whereas homogeneous catalysis are still preferred under laboratory applications reactions with this we conclude this our discussion on olefin metathesis reaction and we are going to alkene metathesis reaction and we are going to take up a cross metathesis another variant of olefin metathesis reaction in more detail when they meet in the next class till then goodbye and thank you you


Welcome back everyone. Today I wanted to talk about acquiring an Android phone on a Windows system. So a prior video I talked about acquiring an Android phone on the Linux, and it's a little bit different. The process is basically the same, but some of the commands are a bit different. So I thought I would go over how to acquire an Android phone on Windows. So the first thing we need for trying to acquire the phone is the Android Studio SDK. So basically go to this website and I'll put a link below the video. Go to the website and go to SDK Platform Tools for Windows and download this. And you'll get a zip folder. So extract that zip folder, I've just extracted it to the desktop. If you're actually doing this on your forensic workstation, extract it into some location, you'll keep it and add it to your path. I'm not going to add this to my path right now, but if I was doing this on a real workstation, I would be adding it to my path. So once we get the SDK and the Android debugging bridge ADB, we look inside the Platform Tools folder and we have this ADB.exe file. The next thing we need on Windows, Windows does not have Netcat built in. So one of the tools I was using for Linux was Netcat. So I am going to download and install from inmap.org incat, which is basically an incat replacement. It works almost exactly the same. It has a few more features, but I'm going to be using incat. So download incat from inmap.org. And whenever you open it up, you also download a zip file from here. You can download a zip file from here. Whenever you download that zip file, you open it up. It's just incat and a readme file. And I copied the incat executable into the same folder as the Android, as ADB, the Android SDK. And the reason that I did that is because it just makes it easier to type. If everything is in one folder, then I can just type the command names instead of the full paths. Again, I have not added any of these to the path in Windows, so I'm just going to do that. Then the next thing we need to do is get the entire location of where the tools are, if it's not in your path, and open up a terminal or a command line. So I'm just going to use standard command line from Windows to CMD, and you get this black command line window. I already have one opened up. And right now I'm in users test, so I'm going to CD change directory and then paste in the location where my tools are located and hit enter. So now I'm inside users test desktop platform tools. And if I do dir, then we can see that I have incat, which is good, and ADB. So once I'm in that directory and I know that the tools are there, then I want to test if I can actually run the tools. Let me expand this a bit. So I want to run ADB.exe-h, and that should show me a help menu if it runs. And okay, that's the help menu. And next I want to try in incat-h, and that should show me a help menu. So I got the help menu on both of them. That means that my applications can run. So now let me check here. So I've already connected the Samsung Android phone to this Windows forensic workstation. What I would do, what I need to do now is run ADB.exe and devices. And we want to get a list of the Android devices connected to this system. Okay, so ADB wasn't running, so it's now connecting, started successfully, and it shows as unauthorized. So if I check the phone, the phone now is asking me if I want to authorize this connection, if I can unlock. It's asking me if I want to authorize this connection, so I say okay on the phone. So once I've authorized the device, I had to disconnect it and reconnect it, and then it's detected. So the reason it wasn't showing up properly is basically because I'm running it in a virtual box, a virtual system. On my main system, there's no problem. So now we have, instead of unauthorized, I have the device itself. So what I would normally do now is send the software, send the APKs for rooting the device and for busybox into the phone and install it in the phone. So I would do that, if I had the APKs downloaded, I would run ADB-D, install KingORoot.APK. Now you can just download this APK, I'll give the link below as well. And then once that's installed, I would run busybox.apk. And then that would send both of these applications to the phone and install them. Then on the phone, I need to run first KingORoot and root the device, get root access to the device. Once the phone is rooted, then I need to run the busybox application and install the utilities into the system, busybox utilities into the system. So even if the applications are installed in the phone, I still have to run them to root the device and install extra utilities. I'm not going to do that now. If you want to see how to do that, see the video about acquiring an image from an Android, sorry, from a Linux computer. So I'll put a link to that as well. It's exactly the same process. It's just how you just running the applications on the phone, very, very straightforward. Okay, so next this phone is already rooted and I already have busybox installed on the phone or the applications, utilities installed on the phone. So I'm going to do ADB-DShell and I'm going to get a shell or shell access to the device itself. Okay, so enter. Okay, so we can see that the command prompt has changed, right? So I have shell at basically the phone name. And I want to test if I have root access already. So I'm going to do ls slash data and I should not be able to access this directory if I'm not root. So it says permission denied. Okay, that's exactly what we expect. That's what we want to see. Next, I'm going to do su to switch user and get root privileges, hopefully. So you see that my username changed from shell to root. Okay, that's what we want to see. So ls slash data. And if I'm root, I should get access to all of the directory, the directories inside data. Okay, so if I see that directory listing, then I have root access and everything is looking good. The next thing I need to do on the phone is do cat slash proc partitions. Cat slash proc partitions. And this is proc partitions is a file that has a list of the disks and partitions in the system and cat just reads that file. So here we see, once we do that, we read all of the disks and partitions that are available. Everything with a P is probably a partition. And then this MMC block zero is most likely the physical disk. Okay, so I want to remember write down MMC block zero. Right. Okay, now, now that we know that we have root access to the device, we have root access to the phone. And we know which device which physical disk we want to image or the physical disk name. So I'm going to open up another command line. Okay, so I need to CD desktop, what was it called tools, platform tools, platform tools. So I'm going to go back into the platform tools. So now this top command line is the phone. I'm accessing the phone. This bottom command line is my local forensic workstation, the windows workstation, and I have all of the tools inside here. So I'm in the platform tools folder and in Caddy XC and ADB are in there. Okay, so from the local computer, the local forensic workstation, I want to run ADB forward TCP 8888 and then TCP 8888. Okay, what this is doing is telling ADB to forward any traffic from TCP port 8888 to basically just forward on port 8888 to and from the phone. Okay, so the phone and the computer have a connection any traffic that goes on 8888 gets forwarded forwarded over. Okay, so now I've sent that command to the phone. So now all of the traffic on 8888 is being forwarded to the computer. Right, and then I need to on the phone, set up a listening connection so that way I can listen on port 8888. So we want to do DDIF equals slash dev block MMC BLK BLK zero busy box NC dash L dash P 8888. Now what this is basically says is NC is net cat. So net cat, listen on port 8888. And whenever a connection comes in on that port, send all of the data like read, read the MMC BLK zero this this disk, read that disk and send all of the data through this. So whenever there's a connection made to the port 8888 on the phone, send all of the hard disk to whoever is making that connection. Okay, so yeah, basically this is just listening for a connection whenever a connection is made, send the data through that connection. Okay, so now I need to hit need to start it. And now it's just waiting for a connection to come in on port 8888. Okay, so back on this was on the phone, back on our forensic workstation, I need to initiate the connection. Okay, so in Linux, I just used in C, but in Windows, we have in cat.exe again, pretty much the same the same procedure, same command just in cat instead of in C. I'm going to do<PHONE_NUMBER>. What that says is make a connection on port 8888 to the local host. And because we have forwarding setup, it will make a connection basically to the phone. The phone will then send us back all of the data from the hard drive. So we need to do something with that data. Let's pipe it to a file called Android dot DD. Okay, dot DD is the basically the extension for a raw disk image. I'm just going to call this Android right now because it's a test. So what we're doing is initiating a connection on port 8888. This busy box net cat is listening for the connection whenever it hears it, it will read the hard drive and send the hard drive data back. We will take that data and save it into Android dot DD file on our local computer. Now this Android DD file is going to end up in the platform tools folder, this platform tools folder, and most likely, especially if you're doing a real case, you probably don't want to save it into the same folder that you're using your tools in. So I would save it into a case folder. I would have a case folder set up with a case structure set up. So think about where you're going to save this right now. I'm just saving it inside the platform tools folder. But you really should be saving it in some sort of case file separately. So if we hit enter, now both of these connections are this one's listening and it's sending data. This one is waiting for basically it's receiving all of the response right now. If we go into the folder, we have Android DD and we can see it's 816k. If I refresh, then you can see that the size is going up as the data is copied over. Now copying this will take actually quite a while. It's going over USB. So it will take a good bit to copy everything. But whenever you finish, you will have a full physical disk image. If you go to cybercrime tech, I do a little bit with disk images. I do a little bit with disk images using the sleuth kit and you can see the, for example, the partition structure with sleuth kit. So now we're copying the physical disk image and that's getting copied up. Whenever both of these commands, whenever the command is finished, whenever we've read the entire disk, both of these commands will exit. So you know you're finished whenever the commands exit. Make sure that you check the size of the physical disk that you collected versus the size reported by the phone. And then the first thing we have to do after we collect the image is make a hash of the image. So make sure once you collect this disk image, this android.dd and it's finished, then make a hash of the disk image, document that hash or sign the image. And then to kind of clean up everything, you need to uninstall busybox utilities from the phone and then remove root access from the phone. And then remove both the root application and the busybox application from the phone. So kind of cleaning up our traces a little bit. Now, of course, we've already talked a little bit about the fact that this will change things. It does change things in the phone. So be prepared to explain, you know, why are you changing things? How are you changing things? So that's pretty much it for how to acquire an android physical disk image from Windows. It's almost exactly the same as Linux. I'm just using a few tools that are not built in like in cat that you can easily download. Okay, that's it for today. Thank you very much.


Hey everybody, Dr. O here and this video we're going to talk about atoms. So I like to call atoms the basic unit of matter, right? The entire physical world which is made up of matter is made up of these atoms and then these atoms form together to form every chemical that we have. How these atoms behave determine which chemical reactions occur and which chemicals we have in our physical living world. So I already called it the basic unit of matter but the textbook definition of an atom would be the smallest quantity of an element that retains the unique properties of that element. So here we see helium and atom of helium is the smallest amount of helium that can exist. So that's how you would define what an atom is. Now atoms as you can see here are made of subatomic particles and the three that we talk about are protons, neutrons and electrons. So protons are positively charged and in the nucleus in the center of the atom in the core. Electrons are negatively charged and they're going to be in a cloud on the outside of the nucleus and neutrons are neutral and they're also in the nucleus. So remember P for P protons positive and for N neutrons are neutral meaning they don't have a charge and then electrons are the negatively charged subatomic particles. As far as weight go protons and neutrons make up the mass of an atom. So if you look at the mass number of an atom it's going to be the number of protons plus the number of neutrons. Electrons are so tiny it takes about 2000 electrons to equal the weight of one of the protons or neutrons so they're not they're not counted in the weight. I already mentioned the protons and neutrons are stay there in the nucleus the electrons they were around the outside of the nucleus and they they spin or were around it at nearly the speed of light in what's called an electron cloud. So the key thing I will say and I'll say this in several videos the key thing I want you to know about atoms is what happens if you change any of these three ingredients. So an electrically neutral atom most atoms are going to have the same number of protons neutrons and electrons. If you change the number of electrons you will have given this this atom a positive or negative charge and now it's an ion I'll cover that in a separate video. If you change the number of neutrons in this you now have an isotope of this element I'll cover that in a separate video and if you change the number of protons you now have a new element. You cannot change the number of protons the number of protons determines the atomic number of an atom which determines where it sits on the periodic table. So I'll cover that with a periodic table. All right so we are looking at what's called the planetary model. I usually call this the Bohr's model where you see the protons and neutrons in the nucleus and the electrons worrying around the outside but they don't follow this beautiful path. They're not like rings around the outside of a planet. They are whipping around the nucleus in a very erratic manner. We can only predict basically the vicinity that they're in not exactly where they are. So this isn't this is a great model a simplest model to draw but atoms look more like this. This would be the electron cloud model which means that the electrons in this elemental helium here this atom of helium are going to be worrying somewhere around the nucleus inside this cloud. Now the nucleus is going to have a positive charge because that's where your positive protons are. The electrons have a negative charge and just like a magnet right the opposites attract. So the positive nucleus is keeping these negative electrons from leaving from traveling too far away unless something pulls them away as we'll as we'll see with chemical reactions later. All right I think that's all the the basics that you need to know about the structure of an atom. We will talk about isotopes and the periodic table and all that and videos coming up. So I hope this helps. Have a wonderful day. Be blessed.


The study investigates the association between long working hours and health by defining long working hours as greater than 40 hours per week or 8 hours per day, minimizing the influence of shift work, and emphasizing the importance of reference groups. The results show that long working hours have significant adverse effects on most health outcomes, including depressive state, anxiety, sleep condition, and coronary heart disease. However, further studies are needed to appropriately address the definition of long working hours and shift work. This article was authored by Akira Benai and Akiko Tamakoshi.


This study aims to assess factors associated with COVID-19 vaccine hesitancy in Portugal using data from a community-based survey, COVID-19 barometer, social opinion, conducted from September 2020 to January 2021. The study found that COVID-19 vaccine hesitancy in Portugal was high, with 56% of respondents waiting and 9% refusing to take the vaccine. Several factors were associated with both refusal and delay, including being younger, loss of income during the pandemic, no intention of taking the flu vaccine, low confidence in the COVID-19 vaccine and health service response, worse perception of government measures, inconsistent and contradictory information, and answering the questionnaire before the release of safety and efficacy information about the vaccine. The study highlights the importance of building confidence in the COVID-19 vaccine through effective communication and increased trust. This article was authored by Patricia Soares, Joao Victorosha, Marta Moniz and others. We are article.tv, links in the description below.


For many years I've been going through the magazine every year and admiring the women on this List and I know some of them personally some of them work in my office. Some of them are my clients They are absolutely admirable. The work is absolutely admirable and when I found myself on this list I was absolutely thrilled and then when I came here and I realized that I have made it to the top 20 I think I I would have fallen off the chair had my husband not held me back. I Have Actually, I've been very lucky and I have to be really honest about this because I have been very lucky with my male bosses as well As my female bosses and I have said this in various interviews that I don't think I would have been where I where I have where I am today had it not been for the bosses that I have had and As far as difference between male and female bosses, I think that I have had equally good male and female bosses So I don't think it would be fair for me to say that one is better than the other But I do want to say that the idea that I should be on this list was that of Hepsiba Patak Who is a female boss and women championing women is the way to go


Item number SCP-648 Object Class Euclid Special Containment Procedures As SCP-648 cannot be moved, it is contained on site under the cover of a secondary entrance that is closed indefinitely for maintenance. At least two armed undercover guards, disguised as site workers, must be on duty at all times, and any individuals attempting to gain access to SCP-648 must be detained for questioning. Exploration or experimentation with an SCP-648 may only be performed with prior permission from at least one Level 4 personnel. Description SCP-648 is a hidden entrance of the Red Hedge Maze, near Data Expunged. Although no official record of this entrance exists, evidence suggests that SCP-648 was incorporated into the Hedge Maze shortly after its construction. When subjects enter the maze via SCP-648, they are displaced to what appears to be an extra-dimensional space separate from the real maze. So far, several anomalous properties have been observed. The maze behind SCP-648 blocks all radio transmissions, preventing communication or remote recordings of the inside of the maze. The maze behind SCP-648 has a size inconsistent with the Red Hedge Maze. Manned exploration attempts have explored over 14 square kilometers of maze, without reaching any exit or edge to the maze. The topography and layout of the alternate maze occasionally shifts, with the time between each shift completely unpredictable. The lower time limit of these shifts is approximately 5 days, and the maze has lasted for as long as 50 days without noticeable shifting. These shifts can cut off exit from the maze, trapping personnel inside. The maze is in a perpetual state of twilight, with no discernible sun, moon, stars, or other celestial references. The maze is also shrouded with a constant fog that reduces visibility to less than 10 to 20 meters. Exploration teams have encountered living creatures within the maze at distances of greater than 2 kilometers from the entrance. These creatures appear to be data-expunged, and have proven to be extremely dangerous. And as such, all teams should try to avoid them if at all possible. SCP-648 came to the Foundation's attention on 19- after two young children discovered the anomalous entrance and disappeared inside. Amnestics were administered to the parents of the children and several witnesses, and a cover story planted. Addendum 648-1 Initial Exploration Incident Log After attempts to remotely explore the maze failed due to the inability to transmit radio signals from within, a manned exploration of the maze was approved by 05- and conducted on 2000- by members of Mobile Task Force Data Expunged, led by Agent K. After traversing approximately 3 kilometers within the maze, the team encountered a data-expunged, which roared loudly and charged the team. Although agents were able to kill the creature using their personal firearms, the sounds of additional data-expunged approaching from nearby forced the team to retreat before they were able to collect any samples that could be later analyzed. Agent K has requested additional firepower for further exploration attempts. Addendum 648-2 Exploration Log 2004 An attempt to scale the wall of the maze was made using Class D personnel, although extremely difficult due to the anomalous slipperiness of the wall and the presence of thorns and data-expunged. Subject D6443 was able to finally scale a wall after being attached to a high-strength tether with over 500 meters of line. Experiment team noted that the voice of D6443 was extremely muffled and distant, despite being no more than approximately 2 meters away from the team. D6443 was instructed to explore the immediate area and tried to find a connecting passage. After approximately 18 minutes and over 350 meters of line played out, the line suddenly went taut and immediately slackened. When retracted, the line was found cleanly severed and no trace of D6443 was ever found. Further attempts to scale the walls of the maze have been suspended, pending investigation into possible inconsistent spatial properties. Addendum 6483 Incident Log 2004 During a manned exploration attempt, Agent M was encountered, who had been lost to an unexpected shift during a previous attempt nearly months ago. Agent M was disheveled, extremely gaunt, and his equipment and clothing were missing or in tatters. The agent screamed, They weren't real. None of you are real at the exploration team before running deeper within the maze. Team attempted to pursue the agent for approximately 20 minutes before calling off the search and returning. Addendum 6484 Incident Log 2004 A breach was reported at the SCP-648 containment station. Upon arrival, agents found that the station had been attacked from the inside. Revised containment procedures are under review and additional guards are to be posted until further notice. Lesson complete. If you missed the previous orientation, go watch SCP-647, Hungry Box, right now. Or for the complete course, watch this playlist.


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