There are plenty of materials out there that make good semiconductors, the question is: can we make them?
Moly disulfide is a material a couple of different graphene groups have been looking at (hey, we know there's an issue with graphene). What this paper really means is that the Ecole group has figured out how to *make* MoS2 better than other people, and that's really the hard part. Of course, they're still making devices using scotch tape exfoliation...
So the peer reviewed article claims it takes 24-48 hours for plants to detect these changes. It's not as easy as just saying that chemistry happens fast. Binding TNT to the receptor on the plant sets of a chain of interactions which cause certain DNA sequences to be expressed, leading to production of enzymes which destroy pigments in the plant. There's a lot of membrane crossing and diffusion involved, and that all takes time.
The mammalian sense of smell takes about 0.2 seconds to register a response electrochemically. It's completely different, there's no genetic signaling involved. Electronic sensors using mammalian proteins can respond at a similar speed. (Those proteins would not function the same way in a plant, in case you're wondering.)
Of course, sensors which use something other than proteins respond even faster, don't fall apart after a few days, and can be used in all kinds of weather.
Ah, so I shouldn't blame the people who were voted into office, nor the people who put them there. It was a blameless mismanagement? There was someone who decided to not only give themselves hefty pensions, but also grossly under-fund the pensions.
Yeah, it is a remarkably small number of people with cushy government pensions. It's really hard to imagine how they could bankrupt local governments paying for that tiny, insignificant number of people. Yet somehow we managed to do it!
There are cities in New Jersey and California which have had their governments removed due to crushing debt and corruption. Now, some people don't get to vote for their local (now court-appointed) government. Why is that? Who put those terrible, terrible administrations in power? Who was part of them?
When the Boomers were the ones running the country, why weren't there better people around willing to serve?
I know you're going to get some Boomers calling for your head about this post, but they should realize that this is not some fringe opinion. There are US cities (San Diego comes to mind) that are considering declaring bankruptcy simply so they wont have to pay any Boomer pensions. Financially, it is impossible for us to pay for their retirement with the jobs we have available. The math simply does not add up. What choice do they have? It's either have a city government or pay Boomer pensions. They can't do both in the next 15 years, so the Boomers in power may choose to keep their political positions and sacrifice the city pensions. There's a tricky problem in there.
Completely cutting them off will not work. We need those guys to retire and get out of the way. They will never leave the workplace, and never leave positions of power if we don't make things nice and easy for them. Why should they leave if there's no retirement and no medical care?
I'm not really sure what we can do, but it would be nice if people in positions of power didn't pretend like the Boomers are "the most vulnerable" part of our society. What a joke.
We can't just wait for them to spend themselves out of business like is happening in local government. The federal government will last a lot longer before debt forces them to fold or succumb to inflation, so they won't live long enough at the top to face the same choices places like San Diego face.
We have a long tradition of incoherent ranting in this country! The deep and meaningful message here is that people here still base their view of the country's future around 1) their wallet and 2) an arbitrary party affiliation that really has nothing to do with actual personal views.
The way things are going now, the scientific culture of biology ("shotgun" testing and details over derivation) is making inroads into the rest of science and engineering, not the other way around. Even in something like as computational physics, some (not most) students will not understand the physics they're trying to test, focusing only on making more, faster, higher density models rather than correct or improved models. I don't think there's anything inherently wrong with a "shotgun" approach research, but I think it needs to be balanced with research focused on fundamental understanding.
The reason for this is that there are more research biologists than the number of research scientists in all other fields put together. Biology so dominates the science landscape that working in another (even major) field often feels like a "niche" position.
I don't know if you're shooting for "look, a ghost!" or "look, a fireplace," but it's really easy to see some "unexplainable" readings with a lot of different tools. Pick something that can detect small amounts of voltage, sound, light, temperature... any one of them will work.
A common one is a hand-held voltage meter. Stick it on the lowest voltage setting and connect a couple of wires to it. You can even wind/shape the wires onto a "ghost sensing" stick or rod if you'd like. While walking around just about anywhere, you'll find many locations or pockets of air that cause small voltages to appear. Depending on your point of view it can be due to an old fireplace, the quirks of the local ventilation or a ghost.
The grad students in my lab do this to new undergrads to try and convince them the lab (in the basement of a 100 year old building) is haunted.
What's the deal with this? This isn't about smart people. There's no one so smart that they can't be replaced with someone just as smart, but a better fit for the group. (Of course, if the team leader is the problem...)
Also, one group's jerk can be another group's solid team member.
I took Computer Science at a California high school a long time ago. We programmed in BASIC... my final project was a terrible, terrible video game. Ok, everyone's final project was a terrible video game. It was definitely not just a typing and using applications class. Now, we are talking about public education, but surely not every school has forgotten how to teach a basic programming and algorithms class.
Being reasonably alarmed, I actually looked at the YouCut website, which is oddly not linked in the summary. Every week they pick various user submitted ideas to cut spending and have people vote on them. They voted and it turns out people don't want to cut the NSF budget. That makes me feel pretty good, actually.
I have no problem with someone asking the question: "Is the NSF budget bloated?" I would have a problem with a politician who decides the NSF budget needs to be cut without trying to get some feedback first.
Also, the budget may not be huge, but the way NSF money is allocated certainly could be improved. The decades long focus on training has caused problems in the labor market, as you can easily get funding to train a PhD, but not funding to hire one. This results in lower quality work, as you are constantly teaching new people and never taking advantage of expertise. "Research" faculty used to be a common thing in physics (corporate research also used to exist), but you only find those positions in biological sciences now.
I've been on a jury a few times (just lucky, I guess), and there is usually an expert brought in. Sometimes the prosecution can just get the psychologist or lab tech who is on staff to explain their measurement/diagnosis. The problem is, no matter how good the expert is, the prosecution MUST ask the correct questions or the jury is totally confused about the facts of the case. That is a major pain in the ass during deliberations. There are some people who, despite clear instructions from the judge, just don't understand what their role as juror is. As long as this is what the system is, the best the lawyers can do is try to explain as much as possible (or not...).
It's nice to grow fuel (or algae food), but there are other good solar fuel options. Inorganic catalysts (iron oxide is this year's sexy "new" catalyst) could use some funding too.
That's a pretty standard anti-cheating technique, entrapment is a bit of a strong word there. I would, however, be royally pissed at any proctors who took it upon themselves to modify tests without my knowledge. Hopefully the professor was pissed about the results and not that you did it without telling him.
I've worked in departments that required I give a version of a standard test (usually part of the final) so that my classes could be compared to classes taught by other people or in previous years. It is a common testing approach though, and is used for tracking teacher performance. At least this guy realized he's not actually improving.
The first graphene production was done in the 1990s, about 10 years before Geim, in a manner very similar to that done by Tour here (in a furnace at high temperature, with a metal catalyst). The guys back then didn't think about how to isolate the graphene from the metal catalyst it was sitting on, and did nothing beyond simply showing it was there. Novoselov (Geim's postdoc) figured out how to get graphene onto a surface appropriate for microelectronics with scotch tape (had nothing to do with pencils, just tape on pure graphite). After that, people went back to the furnace method to scale up production.
We have no shortage of scientists in the US; there's actually a good argument that we have a big surplus compared to the number of researchers investors and businesses are willing to fund. We've increased the number of people we're training while simultaneously experiencing the near complete destruction of the commercial basic science R&D market (hint: pharmaceutical research =/= basic science). Research is done in universities, then moved into startups which employ 1 PhD scientist and a handful of engineers on a shoestring budget. That startup is then blown out of the water by a bigger government-academic-commercial cooperative effort from Korea, China, Brazil...
Well, we did a good job training them in capitalism!
Of all the problems with the University system in the US, why bring this up?
UCLA gets the most applicants? UCLA is the largest state college in the most populous state in the country. Hardly shocking that it gets a lot of applicants.
How about we talk about the problems with recruiting kids into dead-end majors, the lack of practical training, the idea that even an exhaustive college education isn't sufficient (post-doc anyone?), the student-as-labor model of research or absurdly high administrator salaries?
There are better security systems than these full body scanners. It shouldn't be necessary for us to sue the government to get them to scrap them. These things have routinely failed to detect explosives in fairly simple testing. Microwave scanners are great for many things, but stopping bombs is not one of them. If they want to detect explosives or chemical agents, then why not use detectors for explosives and chemical agents? It is mind boggling to me that they have invested so much in this technology, when it's obviously technologically and ethically flawed.
... and no, that I work on chemical sensors plays *no* role in my arguments against these things... really...
This is a bit like finding out politicians lie during campaigns.
I will often ask new grad students in my lab to try and find a new journal article that will never be superceded by future research. This is, of course, a nearly impossible task. Scientific publications are all a work in progress and represent one group's current understanding of some experiment. In physics (my field), this is all a nice scholarly activity and something that everyone knows and understands at some level. Einstein corrected Newton and one day someone will correct Einstein. The point of all this is to get them to think for themselves; there's almost nothing more frustrating than being in a scientific argument with someone who treats published papers like a fundamentalist Christian treats Bible verses. It's a bit scary to realize the same thing happens in medicine, but not surprising. The fundamental structure of how scientific careers are advanced will need to change if we want to change this behavior.
I don't know Godel as well as some other people here, but I do know physics and you're making a lot of assumptions there, starting with that the universe can be "derived" from a theory of everything. The name is a little unfortunate, but the goal of a theory of everything is to create a unified description of the fundamental forces, not a program to simulate the entire universe. If you wanted to simply say "the theory of everything won't be able to tell you absolutely everything about every particle in the universe," you'd be right, and probably that's where you're going with your incompleteness thing.
More fundamentally though, you're assuming the universe is a logical system. From a physicists point of view, it is a happy coincidence that rigorous mathematics is useful in describing the universe, but there is nothing that demands that this is the case (more practically: we're happy in physics to have assumptions about things like causality and time invariance, where needed).
This may sound crazy to most people, but why exactly mathematics has been so successful in physics is still a subject of debate among physicists: whether mathematics approximates an ultimately imperfect physical reality or mathematics *is* physical reality. I don't think it will be settled soon.
Outrage at Slashdot continuing to pander to the least amongst us by referencing news articles rather than journal publications. Link to the free arXive version proving they're just lazy. Random complaint about the state of the academic publishing industry. Frustrated resignation.
Biased attack against actual published paper. Poorly thought out attempt to show my research is much better/cooler/more practical. Backtracking so that I don't seem like an unreasonable person. Personal view on where the research should go next that is purposefully contrary to prevailing opinion. Specifically mention that I'm a physicist in case anyone who actually read my weasel worded, jargon laced diatribe has any doubts.
I've heard the "I use my phone as a dictionary" line before; "I use my phone as a calculator" was even more popular. It's also used for Google and IM, which is not good. Modern graphing calculators are insane, and it's really unfair to ask students to buy one. The books are expensive enough.
My personal favorite is to require them to take the test in the computer lab, where I know what they're doing and they all have access to identical tools. My rule is if I can see your phone, or some other personal electronics, you are cheating. Period. (That's for the popular: "I just left my phone on top of my backpack" routine.) Books and notes, any paper, is ok. If I see electronics, you fail. Everyone is warned before I pass out the test to either give me their phone or put it away where I can't see it. Don't leave any room for debate of the rules in the middle of the test, students these days are very good at arguing.
If we lived in the simple (some may erroneously call "pigeon") earth-sun system you're thinking of, you'd be right and they'd be exactly equivalent. In real world physics, the results are not the same. One method relies on imaginary forces to couple the entire universe into a rotating frame. There are plenty of mathematically correct results which are thrown out in physics for physical reasons such as requiring infinite energy or violating causality. This is one of them. This is the difference between physics and math.
Slashdot Mirror
Yeah, that's a really good question there.
There are plenty of materials out there that make good semiconductors, the question is: can we make them?
Moly disulfide is a material a couple of different graphene groups have been looking at (hey, we know there's an issue with graphene). What this paper really means is that the Ecole group has figured out how to *make* MoS2 better than other people, and that's really the hard part. Of course, they're still making devices using scotch tape exfoliation...
It's really hard to mass produce 2D materials.
So the peer reviewed article claims it takes 24-48 hours for plants to detect these changes. It's not as easy as just saying that chemistry happens fast. Binding TNT to the receptor on the plant sets of a chain of interactions which cause certain DNA sequences to be expressed, leading to production of enzymes which destroy pigments in the plant. There's a lot of membrane crossing and diffusion involved, and that all takes time.
The mammalian sense of smell takes about 0.2 seconds to register a response electrochemically. It's completely different, there's no genetic signaling involved. Electronic sensors using mammalian proteins can respond at a similar speed. (Those proteins would not function the same way in a plant, in case you're wondering.)
Of course, sensors which use something other than proteins respond even faster, don't fall apart after a few days, and can be used in all kinds of weather.
Ok, I couldn't vote at the time, but I'm looking in the mirror...
Ah, so I shouldn't blame the people who were voted into office, nor the people who put them there. It was a blameless mismanagement? There was someone who decided to not only give themselves hefty pensions, but also grossly under-fund the pensions.
Yeah, it is a remarkably small number of people with cushy government pensions. It's really hard to imagine how they could bankrupt local governments paying for that tiny, insignificant number of people. Yet somehow we managed to do it!
There are cities in New Jersey and California which have had their governments removed due to crushing debt and corruption. Now, some people don't get to vote for their local (now court-appointed) government. Why is that? Who put those terrible, terrible administrations in power? Who was part of them?
When the Boomers were the ones running the country, why weren't there better people around willing to serve?
I know you're going to get some Boomers calling for your head about this post, but they should realize that this is not some fringe opinion. There are US cities (San Diego comes to mind) that are considering declaring bankruptcy simply so they wont have to pay any Boomer pensions. Financially, it is impossible for us to pay for their retirement with the jobs we have available. The math simply does not add up. What choice do they have? It's either have a city government or pay Boomer pensions. They can't do both in the next 15 years, so the Boomers in power may choose to keep their political positions and sacrifice the city pensions. There's a tricky problem in there.
Completely cutting them off will not work. We need those guys to retire and get out of the way. They will never leave the workplace, and never leave positions of power if we don't make things nice and easy for them. Why should they leave if there's no retirement and no medical care?
I'm not really sure what we can do, but it would be nice if people in positions of power didn't pretend like the Boomers are "the most vulnerable" part of our society. What a joke.
We can't just wait for them to spend themselves out of business like is happening in local government. The federal government will last a lot longer before debt forces them to fold or succumb to inflation, so they won't live long enough at the top to face the same choices places like San Diego face.
We have a long tradition of incoherent ranting in this country! The deep and meaningful message here is that people here still base their view of the country's future around 1) their wallet and 2) an arbitrary party affiliation that really has nothing to do with actual personal views.
Business as usual.
The way things are going now, the scientific culture of biology ("shotgun" testing and details over derivation) is making inroads into the rest of science and engineering, not the other way around. Even in something like as computational physics, some (not most) students will not understand the physics they're trying to test, focusing only on making more, faster, higher density models rather than correct or improved models. I don't think there's anything inherently wrong with a "shotgun" approach research, but I think it needs to be balanced with research focused on fundamental understanding.
The reason for this is that there are more research biologists than the number of research scientists in all other fields put together. Biology so dominates the science landscape that working in another (even major) field often feels like a "niche" position.
I don't know if you're shooting for "look, a ghost!" or "look, a fireplace," but it's really easy to see some "unexplainable" readings with a lot of different tools. Pick something that can detect small amounts of voltage, sound, light, temperature... any one of them will work.
A common one is a hand-held voltage meter. Stick it on the lowest voltage setting and connect a couple of wires to it. You can even wind/shape the wires onto a "ghost sensing" stick or rod if you'd like. While walking around just about anywhere, you'll find many locations or pockets of air that cause small voltages to appear. Depending on your point of view it can be due to an old fireplace, the quirks of the local ventilation or a ghost.
The grad students in my lab do this to new undergrads to try and convince them the lab (in the basement of a 100 year old building) is haunted.
What's the deal with this? This isn't about smart people. There's no one so smart that they can't be replaced with someone just as smart, but a better fit for the group. (Of course, if the team leader is the problem...)
Also, one group's jerk can be another group's solid team member.
I took Computer Science at a California high school a long time ago. We programmed in BASIC... my final project was a terrible, terrible video game. Ok, everyone's final project was a terrible video game. It was definitely not just a typing and using applications class. Now, we are talking about public education, but surely not every school has forgotten how to teach a basic programming and algorithms class.
Being reasonably alarmed, I actually looked at the YouCut website, which is oddly not linked in the summary. Every week they pick various user submitted ideas to cut spending and have people vote on them. They voted and it turns out people don't want to cut the NSF budget. That makes me feel pretty good, actually.
I have no problem with someone asking the question: "Is the NSF budget bloated?" I would have a problem with a politician who decides the NSF budget needs to be cut without trying to get some feedback first.
Also, the budget may not be huge, but the way NSF money is allocated certainly could be improved. The decades long focus on training has caused problems in the labor market, as you can easily get funding to train a PhD, but not funding to hire one. This results in lower quality work, as you are constantly teaching new people and never taking advantage of expertise. "Research" faculty used to be a common thing in physics (corporate research also used to exist), but you only find those positions in biological sciences now.
I've been on a jury a few times (just lucky, I guess), and there is usually an expert brought in. Sometimes the prosecution can just get the psychologist or lab tech who is on staff to explain their measurement/diagnosis. The problem is, no matter how good the expert is, the prosecution MUST ask the correct questions or the jury is totally confused about the facts of the case. That is a major pain in the ass during deliberations. There are some people who, despite clear instructions from the judge, just don't understand what their role as juror is. As long as this is what the system is, the best the lawyers can do is try to explain as much as possible (or not...).
biological photosynthesis efficiency ~1%
inorganic photosynthesis efficiency ~10%
It's nice to grow fuel (or algae food), but there are other good solar fuel options. Inorganic catalysts (iron oxide is this year's sexy "new" catalyst) could use some funding too.
That's a pretty standard anti-cheating technique, entrapment is a bit of a strong word there. I would, however, be royally pissed at any proctors who took it upon themselves to modify tests without my knowledge. Hopefully the professor was pissed about the results and not that you did it without telling him.
I've worked in departments that required I give a version of a standard test (usually part of the final) so that my classes could be compared to classes taught by other people or in previous years. It is a common testing approach though, and is used for tracking teacher performance. At least this guy realized he's not actually improving.
Close, but not quite.
The first graphene production was done in the 1990s, about 10 years before Geim, in a manner very similar to that done by Tour here (in a furnace at high temperature, with a metal catalyst). The guys back then didn't think about how to isolate the graphene from the metal catalyst it was sitting on, and did nothing beyond simply showing it was there. Novoselov (Geim's postdoc) figured out how to get graphene onto a surface appropriate for microelectronics with scotch tape (had nothing to do with pencils, just tape on pure graphite). After that, people went back to the furnace method to scale up production.
Exactly right.
We have no shortage of scientists in the US; there's actually a good argument that we have a big surplus compared to the number of researchers investors and businesses are willing to fund. We've increased the number of people we're training while simultaneously experiencing the near complete destruction of the commercial basic science R&D market (hint: pharmaceutical research =/= basic science). Research is done in universities, then moved into startups which employ 1 PhD scientist and a handful of engineers on a shoestring budget. That startup is then blown out of the water by a bigger government-academic-commercial cooperative effort from Korea, China, Brazil...
Well, we did a good job training them in capitalism!
Of all the problems with the University system in the US, why bring this up?
UCLA gets the most applicants? UCLA is the largest state college in the most populous state in the country. Hardly shocking that it gets a lot of applicants.
How about we talk about the problems with recruiting kids into dead-end majors, the lack of practical training, the idea that even an exhaustive college education isn't sufficient (post-doc anyone?), the student-as-labor model of research or absurdly high administrator salaries?
There are better security systems than these full body scanners. It shouldn't be necessary for us to sue the government to get them to scrap them. These things have routinely failed to detect explosives in fairly simple testing. Microwave scanners are great for many things, but stopping bombs is not one of them. If they want to detect explosives or chemical agents, then why not use detectors for explosives and chemical agents? It is mind boggling to me that they have invested so much in this technology, when it's obviously technologically and ethically flawed.
... and no, that I work on chemical sensors plays *no* role in my arguments against these things... really...
I don't
This is a bit like finding out politicians lie during campaigns.
I will often ask new grad students in my lab to try and find a new journal article that will never be superceded by future research. This is, of course, a nearly impossible task. Scientific publications are all a work in progress and represent one group's current understanding of some experiment. In physics (my field), this is all a nice scholarly activity and something that everyone knows and understands at some level. Einstein corrected Newton and one day someone will correct Einstein. The point of all this is to get them to think for themselves; there's almost nothing more frustrating than being in a scientific argument with someone who treats published papers like a fundamentalist Christian treats Bible verses. It's a bit scary to realize the same thing happens in medicine, but not surprising. The fundamental structure of how scientific careers are advanced will need to change if we want to change this behavior.
I don't know Godel as well as some other people here, but I do know physics and you're making a lot of assumptions there, starting with that the universe can be "derived" from a theory of everything. The name is a little unfortunate, but the goal of a theory of everything is to create a unified description of the fundamental forces, not a program to simulate the entire universe. If you wanted to simply say "the theory of everything won't be able to tell you absolutely everything about every particle in the universe," you'd be right, and probably that's where you're going with your incompleteness thing.
More fundamentally though, you're assuming the universe is a logical system. From a physicists point of view, it is a happy coincidence that rigorous mathematics is useful in describing the universe, but there is nothing that demands that this is the case (more practically: we're happy in physics to have assumptions about things like causality and time invariance, where needed).
This may sound crazy to most people, but why exactly mathematics has been so successful in physics is still a subject of debate among physicists: whether mathematics approximates an ultimately imperfect physical reality or mathematics *is* physical reality. I don't think it will be settled soon.
Outrage at Slashdot continuing to pander to the least amongst us by referencing news articles rather than journal publications. Link to the free arXive version proving they're just lazy. Random complaint about the state of the academic publishing industry. Frustrated resignation.
Biased attack against actual published paper. Poorly thought out attempt to show my research is much better/cooler/more practical. Backtracking so that I don't seem like an unreasonable person. Personal view on where the research should go next that is purposefully contrary to prevailing opinion. Specifically mention that I'm a physicist in case anyone who actually read my weasel worded, jargon laced diatribe has any doubts.
Gee, that was fun.
I've heard the "I use my phone as a dictionary" line before; "I use my phone as a calculator" was even more popular. It's also used for Google and IM, which is not good. Modern graphing calculators are insane, and it's really unfair to ask students to buy one. The books are expensive enough.
My personal favorite is to require them to take the test in the computer lab, where I know what they're doing and they all have access to identical tools. My rule is if I can see your phone, or some other personal electronics, you are cheating. Period. (That's for the popular: "I just left my phone on top of my backpack" routine.) Books and notes, any paper, is ok. If I see electronics, you fail. Everyone is warned before I pass out the test to either give me their phone or put it away where I can't see it. Don't leave any room for debate of the rules in the middle of the test, students these days are very good at arguing.
If we lived in the simple (some may erroneously call "pigeon") earth-sun system you're thinking of, you'd be right and they'd be exactly equivalent. In real world physics, the results are not the same. One method relies on imaginary forces to couple the entire universe into a rotating frame. There are plenty of mathematically correct results which are thrown out in physics for physical reasons such as requiring infinite energy or violating causality. This is one of them. This is the difference between physics and math.
Sorry for mis-spelling pidgin.