Hi Reddit! I’m the creator of the American Chemical Society’s Reactions YouTube channel, a weekly series that highlights the chemistry in everyday life. I also manage ACS Productions, the Society’s award-winning video team. I received undergraduate degrees in Genetics and Science Communication from the University of Wisconsin-Madison, and an MBA from George Mason University. I’ve been producing science videos on YouTube for most of the site’s 10-year history. Bill Nye has said that “if you want to teach something, you have to entertain people… Mr. Wizard encouraged a generation of scientists and engineers by doing this.” This entertaining, educational approach is at the heart of Reactions. We’ve produced videos explaining why dogs smell each other’s butts, why a pinch of salt can make bad coffee taste better and how garbage kickstarted the modern chemical industry, as well as episodes on the chemistry of hangovers, tattoos, avocados, bacon, moisturizer and, yes, cats. The series (and its predecessor, Bytesize Science) has received more than 20 million views and grown to 250,000 combined followers on YouTube and Facebook. Reactions episodes have been featured on the Today Show, NPR, Washington Post and more than 100 other media outlets. The series has collaborated with noted science communicators and YouTubers, including Joe Hanson (It’s OK to be Smart), Deborah Blum (The Poisoner’s Handbook), Raychelle Burks (@DrRubidium), Andy Brunning (Compound Interest), Vanessa Hill (BrainCraft) and Rachel Feltman (Washington Post’s Speaking of Science blog), among others. In 2015, Wired featured Reactions in its list of “Science Blogs, Twitter Feeds and Channels We Love.” I’m excited to do this AMA about communicating chemistry on YouTube. Feel free to ask me anything about the making of Reactions, how science videos can reach the public, using social media for science communication and questions about video production and YouTube, in general. I’ll be back at 11 am EST (8 am PST, 4 pm UTC) to answer your questions, ask me anything! [Edit at 11:45am EST:] Thanks for all the great questions! Had some technical issues, but I’m now up and running and replying the qs below. [Edit at 12:45pm EST] OK I tried to respond to as many of these as I could. I’ll pop back online later this afternoon to answer a few more. [Edit 10:30pm EST] Responded to a few more. Thanks for all the great questions – this was fun! And if you haven’t already, head over to Reactions and subscribe: https://www.youtube.com/user/ACSReactions

Hi Reddit, My name is Colin Blakemore. I’m Professor of Neuroscience and Philosophy at the School of Advanced Study, University of London, and Emeritus Professor of Neuroscience at the University of Oxford (where I worked in the medical school for 33 years). From 2003-2007 I was the Chief Executive of the British Medical Research Council, which provides hundreds of millions of pounds for medical research each year. My current research is on human perception, and especially on how our brains put together information from the different senses. But in the past I’ve also worked on the early development of the brain, on “plasticity”, and on neurodegenerative disease (Huntington’s Disease in particular). A list of most of my publications can be found here. To my amazement, I was I knighted in 2014 and I was particularly pleased that it was given for contributions to scientific policy and public communication, as well as for research. For the whole of my career, I’ve been a strong advocate for better engagement between the scientific community and the public about how we use science. In particular, I’ve campaigned for openness and proper debate about the use of animals, which was vital for much of my own research in the past. I recently gave the 79th Annual Paget Lecture, organised by Understanding Animal Research. My talk, entitled “Four Stories about Understanding the Brain”, covered the development of the cerebral cortex, language, Huntingdon’s Disease and Stroke. Watch it here. This is my first AMA, I’m here to talk about neuroscience, animal research, philosophy and public outreach, but, well, Ask Me Anything! I’m here from 4 – 5pm UTC (EST 11 – noon / PST 8 – 9 am) Edit: I MUST FINISH NOW. IT’S BEEN FUN TALKING WITH YOU - SORRY NOT TO BE ABLE TO ANSWER MORE!

Hi, my name is John Hammersley and I am the co-founder of Overleaf, a collaborative writing and publishing system that makes the whole process of producing academic papers quicker for authors and publishers. In a previous life I worked on the first passenger trials for Heathrow’s Driverless Car and I have a PhD in Mathematics. I am here today to discuss successful career transitions and my shift from academia to industry, and then to an academic industry. But, I also open the floor for any other relevant questions. There will also be some live tweeting from @Overleaf and questions using the #askjohnoverleaf hashtag. I’ll be back at 1 pm EST (10 am PST, 6 pm UTC) to answer your questions, ask me anything! UPDATE: Phew - that’s it for now! About 20 questions answered I think, more to come later once I’ve had a break! Thanks for all the great questions and comments, and especially all the kind words about Overleaf. Here’s to exciting times ahead in 2016 :) UPDATE 2: I’ve started answering some of the many questions I didn’t have time to during the hour AMA slot; my apologies if it takes me a while to get to yours, I am juggling work with a 12-week old baby daughter at the moment! Thanks again to everyone for the great questions and comments :)

Scientists value transparency and reproducibility, but are rewarded for highlighting the novelty of unexpected findings. This is one reason why published research findings are hard to reproduce. See, for example, the recent work done by us and the scientists involved in the Open Science Collaboration on Estimating the Reproducibility of Psychological Science (https://osf.io/ezcuj/wiki/home/). When scientists preregister their research, they are making key decisions without being biased by the data they collect, which makes standard statistical tests more effective. Though preregistration is required by law for clinical research involving human medical studies, it is not widely practiced by most scientists. We at the Center for Open Science have $1,000,000 to hand out as prizes for researchers who publish the results of their preregistered research. See https://cos.io/prereg We’ll be back at 12 pm ET (9 am PT, 5 pm UTC) to answer your questions, Ask us anything! Answering questions today: Courtney Soderberg is our Statistical and Methodological Consultant who advises researchers on best practices in experimental design and statistical analysis to make their work more reproducible. Jolene Esposito works with researchers in Africa to to improve the rigor of their work using the tools we’ve made, such as the Open Science Framework (osf.io) April Clyburne-Sherin is our Reproducible Research Evangelist who conducts workshops to train researchers on reproducible research methods and open science tools. David Mellor works on encouraging researchers to preregister their work on the Open Science Framework. Hello Reddit! http://imgur.com/DpMrjKV (edits for formatting, picture, our names) Edit 2 PM EST: Thanks for all of your questions everyone! We’ve enjoyed talking to you. We will come back later today to see if any more questions are up. Follow us on Twitter! @OSFramework

Hello, reddit! My name is David Hemenway. I’m professor of health policy at the Harvard T.H. Chan School of Public Health and director of the Harvard Injury Control Research Center. You can read more about our research on firearms here. Throughout my career I have written and done research widely on injury prevention, including research on the role of firearms, violence, and suicide. My 2006 book, Private Guns, Public Health describes the public health approach to reducing firearm violence, and summarized the scientific studies on the firearms and health. You can watch two recent videos where I discuss why gun violence is a public health issue, and how a public health approach can decrease deaths and injuries from guns without violating the Constitution. I’ll be here from 5:30-7:30 p.m. ET to answer your questions; Ask Me Anything! EDIT: It’s 7:55 p.m. and I do have to go now. Thank you all for your questions! Sorry I didn’t have time to answer many of these questions.

Hi Reddit! My name is Christine Kreuder Johnson, I am a Professor of Epidemiology at the University of California School of Veterinary Medicine’s One Health Institute. Joining me today is Tierra Smiley Evans, a veterinarian and graduate student in epidemiology at UC Davis who developed the primate sampling technique published recently in PLOS NTDs, “Optimization of a Novel Non-invasive Oral Sampling Technique for Zoonotic Pathogen Surveillance in Nonhuman Primates”, that we will be discussing today. CHRISTINE KREUDER JOHNSON – My research focuses on ecological processes that impact wildlife and public health. I am especially interested in finding new ways to investigate disease in endangered species and identifying One Health solutions for protecting human and animal health. Most recently, I work with a consortium of partners on USAID’s Emerging Pandemic Threats PREDICT project to develop global surveillance capabilities to detect infectious disease threats with pandemic potential. We focus on zoonotic viruses that spillover from animals to cause disease in humans and we work at the highest-risk interfaces around the world where new diseases are most likely to emerge. Our published study “Spillover and Pandemic Properties of Zoonotic Viruses with High Host Plasticity” highlights many of the epidemiologic circumstances promoting spillover, amplification, and spread of zoonotic viruses that we are investigating in order to direct interventions aimed at disease prevention. TIERRA SMILEY EVANS – My research focuses on zoonotic disease transmission in human and non-human primate communities in Africa and Asia. I have conducted field research in Uganda, Rwanda, Nepal and Myanmar and I am particularly interested in developing non-invasive diagnostics for wildlife that can enable us to understand disease dynamics in these remote settings. Our recent PLOS NTDS article describes a non-invasive sampling technique that involves distributing a rope for primates to chew on that can be retrieved and screened for pathogens that are present in the mouth. This method provides an alternative approach to anesthetizing wild primates to test for diseases and enables sampling of populations that otherwise would not be able to be sampled. Our methods can be applied to studies examining primates as sources of diseases that could affect humans in remote tropical settings. Our study and its implications for public health is also discussed in a post on the PLOS Student Blog. We are looking forward to answering your questions at 1pm ET today — Ask Us Anything!

Hi Reddit, My name is Jack L. Conrad and I am an Assistant Professor at NYIT College of Osteopathic Medicine and a Research Associate at the American Museum of Natural History (AMNH). My research focuses on the evolution, morphology, and paleontology of modern and living snakes, amphisbaenians, mosasaurs, and other ‘lizards’ (Squamata). Squamates first appeared around 245 million years ago, have a good fossil record for the last 155 million years, and today include more than 9700 living species; that’s alotta Squamata! One of the most difficult problems in understanding squamate evolution is snake origins. We know that many branches of the lizard family tree lost their limbs – there are limbess geckoes, limbless skinks, limbless cousins to the Komodo Dragon, etc. – but we don’t know from which branch of the lizard family tree snakes come. It’s really become quite a headache, but also a fun area for investigation. Studying this problem, and other areas of squamate evolution, leads scientists like myself to understanding other natural science questions and phenomena, including (but certainly not limited to): What was Earth like at various times in the past? Are there physical constraints on how big a lizard can be on land? In the seas? How did lizards move across the planet as they evolved over time? I recently published a study titled “A new Eocene casquehead lizard (Reptliia, Corytophanidae) from North America” in PLOS ONE. This study described the earliest known species of casquehead, or Jesus lizard, known. Importantly, this animal lived in Wyoming when the planet was much warmer than it is now and because its modern relatives live only in the tropics, it raises questions about what might happen if our planet warmed up a few degrees. I will be answering your questions at 1pm ET. Ask Me Anything! I love everything about reptiles and evolution. I may not have all of your answers, but I will certainly enjoy talking with you about all of your questions! Don’t forget to follow me on Twitter @ammoskius.

Hi Reddit! I am a postdoctoral researcher at the University of Rochester Medical Center. My background is in clinical psychology and Deaf mental health. I am currently studying how early language exposure (or lack thereof) can affect medical and behavioral health outcomes. My research is supported through a joint program for deaf postdocs at the University of Rochester and the Rochester Institute of Technology. I’ll be back at 1 pm ET (10 am PT, 6 pm UTC) Ask me anything about my research, or what it is like to be a Deaf scientist! EDIT: Hi r/science (and Reddit), I am here! WOW, there are some great questions here. I intend to answer as many as I can, keep them coming! EDIT 2: It is now 3pm EST, I need to bike home (yes, I winter-bike!). I am enjoying your questions and I plan to continue answering questions tonight. EDIT 3: I need to take a break for the night! I plan to continue answering questions tomorrow, and the rest of the week until I get to everyone! Feel free to ask something, I will get to it!

Hi Reddit, Last year, I retired from Tufts University’s Fletcher School of Law and Diplomacy (the only chemist on the faculty!), where I founded and directed the Center for International Environment and Resource Policy (http://fletcher.tufts.edu/CIERP) for 22 years. I supervised many masters’ and doctoral students during that time, including the co-chair of the Paris climate negotiations. I continue to work on climate science and policy, energy, water, forests and oceans to develop scientifically valid and effective strategies and policies. I served as a lead author on five IPCC reports over a 19-year period. Until recently I served as Chief Scientist at Earthwatch Institute (http://earthwatch.org/) and continue to serve as the Chair of their Science Committee. I also serve on the board of directors of Woods Hole Research Center (http://whrc.org/), ranked as the most influential climate think tank for the past two years, and several additional environmental science and consensus building organizations. The science of climate change is complex, and the politics are more so. I have always found the interaction between the two to be fascinating, and remember being shocked as a young scientist that science did not always determine the political outcome of a policy process. I want to share with you the role of science in the outcome of the Paris climate negotiation that just ended on December 11th, 2015. A bit of history: back in the 1980s, a group of scientists convinced some governments that based on their research, the release of heat trapping gases into the atmosphere would heat the earth to a point where there could be uncontrollable and irreversible warming with devastating consequences for all life, including humans. This science prompted two actions. The first was to create the Intergovernmental Panel on Climate Change (IPCC) to provide scientific input to governments on the science, impacts, vulnerabilities, adaptation, and mitigation of climate change. The second was to negotiate an international treaty, the UN Framework Convention on Climate Change that was signed by 154 nations in 1992. The Paris negotiations were the 21st meeting of the parties to the original treaty, and its actions both utilized and ignored science in the final outcome. I invite you to join me in a discussion about how science and policy came together and diverged over issues like the 2oC global temperature goal during the recent Paris talks. I’ll be back at 1 pm EST (10 AM PST, 6 pm UTC) to answer your questions, ask me anything! EDIT: We are live! EDIT IN CLOSING: Thank you all for your engagement, and your thoughtful questions. It has been very gratifying to hear your concerns. Let me close with one final thought. So many actions to address climate change have many additional benefits for providing sustainable energy to all and lift people out of poverty. There would be far less damage to the planet and our health if we can make the shift away form fossil fuels. As I said earlier, we also need to do Restorative Development to mobilize the biosphere so that we improve our forests and land quality every time we use them instead of constantly degrading them. Perhaps, you will enjoy one of my favorite cartoons as a closing. http://imgur.com/up6yu

My name is Bruce Jakosky (http://lasp.colorado.edu/home/maven/about/teampartners/principal-investigator/) from the University of Colorado. I’m the Principal Investigator of the MAVEN mission, and have an interest in the complex volatile system on Mars, reaching from the deep interior to the region that interacts with the incoming solar wind. My name is Dave Brain (http://lasp.colorado.edu/~brain/David_Brain/Home.html), and I’m a member of the science team and an Assistant Professor in Planetary Sciences at the University of Colorado. My research focuses on interactions of the solar wind with planetary magnetospheres and the implications. And I’m Rob Lillis (http://sprg.ssl.berkeley.edu/~rlillis/), a Research Scientist at the University of California at Berkeley and a member of the MAVEN science team. I’m interested in the energy input into the Mars atmosphere that comes from solar storms and the corresponding response of the upper atmosphere. The MAVEN (http://lasp.colorado.edu/home/maven/) spacecraft has been in orbit around Mars for just over an Earth year. We’re getting enough measurements that we’ve now been able to see the general behavior of the upper atmosphere and also its response to a significant solar storm. We’ve determined that atmospheric gas escapes from Mars to space in large enough quantities that this loss probably was a major mechanism for changing the climate on Mars and turning it from a warm, wet environment to the present-day cold, dry environment. We will be back at 2 pm EST (11 am PST, 7 pm UTC) to answer your questions, Ask us anything!

A document by Nancy_Krieger . Click on the document to view its contents.

My name is Mazhar Ali and I am a researcher with the Max PIank Institute for Microstructure Physics in Halle, Germany and also at IBM in San Jose, California. Before that I was at Princeton where many of us worked on and discovered some of the first Dirac and Weyl materials, including the first “type II” Weyl semimetal, WTe2, which was on the frontpage of r/science last week. Dirac and Weyl materials are a super hot topic in condensed matter physics right now, but has branched out and captured the attention of chemists, particle physicists, materials scientists, electrical engineers and more! These materials host massless dirac electrons (similar to graphene) and so can have “light-like” electrons moving at extremeley high mobilities! Recently, people have been able to use the intracies of the electronic structure of a material to massage these massless dirac electrons into becoming Weyl electrons; still massless, but with the added bonus of having spin up and spin down be energetically different! We will see in the near future what we can do with these new particles, but first we need to understand everything better. Out of the 3 camps of Fermions (Weyl, Dirac, and Majorana) we had previously only realized Dirac fermions in real life. Now we have realized the 2nd camp, Weyl! Majorana might be just around the corner too! It is a very exciting time to be involved! I am here to answer any questions you all might have about Dirac and Weyl materials, physics, chemistry, etc! Or, if you just want to know about solid state and materials chemistry, AMA! A few links to a few of the relevant papers (obviously there are loads more): Titanic Magnetoresistance in WTe2: http://www.nature.com/nature/journal/v514/n7521/full/nature13763.html Type II Weyl Semimetals: http://www.nature.com/nature/journal/v527/n7579/full/nature15768.html Cd3As2, a Dirac Semimetal: http://www.nature.com/nmat/journal/v13/n7/full/nmat3990.html Ultrahigh electron mobility in Cd3As2: http://www.nature.com/nmat/journal/v14/n3/full/nmat4143.html Type I Weyl Semimetal (open access): http://journals.aps.org/prx/abstract/10.1103/PhysRevX.5.031013 A very nice viewpoint on Weyl electrons by Leon Balents (professor at UCSB): http://physics.aps.org/articles/v4/36 open access, arXiv versions of most of the above articles can be found through google fairly easily as well. I will be back at 2 pm EST (11 am PST, 7 pm UTC) to answer your questions, ask me anything! EDIT: I am back! May go for lunch in about an hour, but then will be back again after! EDIT 2: Hey all! Gonna take a lunch break, be back in about an hour or so! (Currently 12:20 PST) EDIT 3: Back again!