The information gained by making a measurement, termed the Kullback–Leibler divergence, assesses how much more precisely the true quantity is known after the measurement was made (the posterior probability distribution) than before (the prior probability distribution). It provides an upper bound for the contribution that an observation can make to the total likelihood score in likelihood-based crystallographic algorithms. This makes information gain a natural criterion for deciding which data can legitimately be omitted from likelihood calculations. Many existing methods use an approximation for the effects of measurement error that breaks down for very weak and poorly measured data. For such methods a different (higher) information threshold is appropriate compared with methods that account well for even large measurement errors. Concerns are raised about a current trend to deposit data that have been corrected for anisotropy, sharpened and pruned without including the original unaltered measurements. If not checked, this trend will have serious consequences for the reuse of deposited data by those who hope to repeat calculations using improved new methods.

The photovoltaic perovskite, methyl­ammonium lead triiodide [CH3NH3PbI3 (MAPbI3)], is one of the most efficient materials for solar energy conversion. Various kinds of chemical and physical modifications have been applied to MAPbI3 towards better understanding of the relation between composition, structure, electronic properties and energy conversion efficiency of this material. Pressure is a particularly useful tool, as it can substantially reduce the interatomic spacing in this relatively soft material and cause significant modifications to the electronic structure. Application of high pressure induces changes in the crystal symmetry up to a threshold level above which it leads to amorphization. Here, a detailed structural study of MAPbI3 at high hydro­static pressures using Ne and Ar as pressure transmitting media is reported. Single-crystal X-ray diffraction experiments with synchrotron radiation at room temperature in the 0–20 GPa pressure range show that atoms of both gaseous media, Ne and Ar, are gradually incorporated into MAPbI3, thus leading to marked structural changes of the material. Specifically, Ne stabilizes the high-pressure phase of NexMAPbI3 and prevents amorphization up to 20 GPa. After releasing the pressure, the crystal has the composition of Ne0.97MAPbI3, which remains stable under ambient conditions. In contrast, above 2.4 GPa, Ar accelerates an irreversible amorphization. The distinct impacts of Ne and Ar are attributed to differences in their chemical reactivity under pressure inside the restricted space between the PbI6 octahedra.

An online knowledge base on the alternate conformations adopted by main-chain and side-chain atoms in protein structures solved by X-ray crystallography is described.

In this work, the mechanism of solvent-mediated desolvation transformation of lenvatinib mesylate (LM) was investigated. Two new solid forms of LM, a dimethyl sulfoxide (DMSO) solvate and an unsolvated form defined as form D, were discovered and characterized using powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, polarized light microscopy and Raman spectroscopy. To investigate the thermodynamic mechanism of solvent-mediated desolvation transformation (SMDT) from LM DMSO solvate to form D, solubilities of LM DMSO solvate and form D in binary solvent mixtures of DMSO and water at different water volume fractions and temperatures (293.15–323.15 K) were measured and correlated by non-random two liquids model. The solubility data were used to evaluate the thermodynamic driving force of the SMDT process from DMSO solvate to form D and the effect of the activities of water and DMSO on the transformation process. Raman spectroscopy was used to monitor in situ the solid phase compositions during the SMDT process from LM DMSO solvate to form D while the solution concentration was measured by the gravimetric method. The overall desolvation transformation experiments demonstrated that the SMDT process was controlled by the nucleation and growth of form D. Moreover, effects of operating factors on the SMDT process were studied and the results illustrated that water activity in solution was the paramount parameter in the SMDT process. Finally, a new SMDT mechanism was suggested and discussed.

The solvent-mediated desolvation process of newly discovered lenvatinib DMSO solvate to form II at different water volume fractions and temperatures was investigated. It is confirmed that the activity of water is the most important factor affecting the desolvation process: the desolvation process only occurs when the activity of water is greater than the activity of DMSO, and one new mechanism of solvent-mediated desolvation process was proposed.

Archaea are motile by the rotation of the archaellum. The archaellum switches between clockwise and counterclockwise rotation, and movement along a chemical gradient is possible by modulation of the switching frequency. This modulation involves the response regulator CheY and the archaellum adaptor protein CheF. In this study, two new crystal forms and protein structures of CheY are reported. In both crystal forms, CheY is arranged in a domain-swapped conformation. CheF, the protein bridging the chemotaxis signal transduction system and the motility apparatus, was recombinantly expressed, purified and subjected to X-ray data collection.

The way that massive stars form remains mysterious, in part, because massive stars are rare and tend to spend their youth shrouded by dust and gas and hidden from view.

The post Radio telescopes give astronomers rare glimpse at a young protostar’s formation appeared first on Smithsonian Insider.

Astronomers are piecing together the reasons for these huge energy outputs, while sorting out why our own galaxy is so modest. The two primary suspects are bursts of star formation that produce many hot young stars, and processes associated with accretion of material onto a supermassive black hole at a galaxy's nucleus.

The post Luminosity of extreme galaxy most likely driven by star formation appeared first on Smithsonian Insider.

Recent geologic mapping of the Medusae Fossae Formation on Mars—an intensely eroded deposit near the northern edge of the cratered highlands—has revealed a wider distribution of its western component than was previously recognized.

The post New mapping of Mars shows Medusae Fossae Formation older than once thought appeared first on Smithsonian Insider.

Samantha-Su Z. Taylor, Nicole L. Jacobsen, Tasha K. Pontifex, Paul Langlais, and Janis M. Burt

Connexin 37 (Cx37) expression profoundly suppresses proliferation of rat insulinoma (Rin) cells in a manner dependent on gap junction channel (GJCh) functionality and the presence and phosphorylation status of its carboxyl-terminus (CT). In Rin cells growth arrested by induced Cx37 expression, serine 319 (S319) is frequently phosphorylated. Preventing phosphorylation at this site (alanine substitution; S319A) relieved Cx37 of its growth suppressive effect whereas mimicking phosphorylation at this site (aspartate substitution; S319D) enhanced Cx37's growth suppressive properties. Like Cx37-WT, -S319D GJChs and hemichannels (HChs) preferred the closed state, rarely opening fully, and gated slowly. In contrast, Cx37-S319A channels preferred open states, opened fully, and gated rapidly. These data indicate that phosphorylation-dependent conformational differences in Cx37 protein and channel function underlie Cx37-induced growth arrest vs. growth permissive phenotypes. That the closed state of -WT and Cx37-S319D GJChs and HChs favors growth arrest suggests that rather than specific permeants mediating cell cycle arrest, the closed conformation instead supports interaction of Cx37 with growth regulatory proteins that result in growth arrest.

Appendices B4 and B5 of Cayron [Acta Cryst. (2019), A75, 411–437] contain equations involving the point group and the metric tensor in which the equality symbol should be substituted by the inclusion symbol.

Here come the stinkbugs...With the cooler temperatures of fall the brown marmorated stinkbug begins a determined quest to find a warm place to spend the winter. Crowding around window screens and searching for other ways to get inside, homeowners in the United States will share their indoor living space this winter with millions of brown marmorated stinkbugs. In this video Gary Hevel, an entomolgist at the Smithsonian's National Museum of Natural History, shares some information about these interesting creatures, as well as some advice about how to deal with those that inevitably gain entry to your home.

The post Smithsonian entomologist Gary Hevel gives information and advice about stinkbugs in your home appeared first on Smithsonian Insider.

A new polymorph (form II) is reported for the 1:1 dimethyl sulfoxide solvate of 2,3,5,6-tetra­fluoro-1,4-di­iodo­benzene (TFDIB·DMSO or C6F4I2·C2H6SO). The structure is similar to that of a previously reported polymorph (form I) [Britton (2003). Acta Cryst. E59, o1332–o1333], containing layers of TFDIB mol­ecules with DMSO mol­ecules between, accepting I⋯O halogen bonds from two TFDIB mol­ecules. Re-examination of form I over the temperature range 300–120 K shows that it undergoes a phase transformation around 220 K, where the DMSO mol­ecules undergo re-orientation and become ordered. The unit cell expands by ca 0.5 Å along the c axis and contracts by ca 1.0 Å along the a axis, and the space-group symmetry is reduced from Pnma to P212121. Refinement of form I against data collected at 220 K captures the (average) structure of the crystal prior to the phase transformation, with the DMSO mol­ecules showing four distinct disorder com­ponents, corresponding to an overlay of the 297 and 120 K structures. Assessment of the inter­molecular inter­action energies using the PIXEL method indicates that the various orientations of the DMSO mol­ecules have very similar total inter­action energies with the molecules of the TFDIB framework. The phase transformation is driven by inter­actions between DMSO mol­ecules, whereby re-orientation at lower temperature yields significantly closer and more stabilizing inter­actions between neighbouring DMSO mol­ecules, which lock in an ordered arrangement along the shortened a axis.

A Landau theory for the wurtzite-based heterovalent ternary semiconductor ZnSnN2 is developed and a first-order reconstructive phase transition is proposed as the cause of observed crystal structure disorder. The model infers that the phase transition is paraelectric to antiferroelectric.

Georgi Dimchev
Apr 9, 2020; 133:jcs239020-jcs239020
Articles

MP3 -> Wave or Wave -> MP3

The explosive growth of information technology is having a profound impact on our lives.

Welcome to the public release of the latest Institute of Medicine report on the quality of health care in America.

To significantly reduce the tens of thousands of deaths and injuries caused by medical errors every year, health care organizations must adopt information technology systems that are capable of collecting and sharing essential health information on patients and their care, says a new report by the Institute of Medicine of the National Academies.

Nurses roles, responsibilities, and education should change significantly to meet the increased demand for care that will be created by health care reform and to advance improvements in Americas increasingly complex health system, says a new report from the Institute of Medicine.

Every year, approximately 100 million* adult Americans experience chronic pain, a condition that costs the nation between $560 billion and $635 billion annually, says a new report from the Institute of Medicine.

Americas health care system has become too complex and costly to continue business as usual, says a new report from the Institute of Medicine

We are pleased to announce that the National Academies of Sciences, Engineering, and Medicine are exploring ways to mobilize our expertise to counter misinformation on the web related to science, engineering, and health.

The National Academies of Sciences, Engineering, and Medicines Task Force on the 2020 Census today issued a letter report and submitted it as a public comment to the U.S. Department of Commerce, which recently requested public comments on the 2020 Census.

Medicine regulatory authorities — including the U.S. Food and Drug Administration (FDA) — should strengthen cooperation with other countries’ regulators to ensure the quality, safety, and efficacy of medicines, says a new report from the National Academies of Sciences, Engineering, and Medicine.

National Academies host three events to explore ways to expand the reach of accurate science and health information online

"Deepfakes" are digitally altered images that make incidents appear real when they are not. Such altered files could have broad implications for politics.; Credit: /Marcus Marritt for NPR

Sophisticated fake media hasn't emerged as a factor in the disinformation wars in the ways once feared — and two specialists say it may have missed its moment.

Deceptive video and audio recordings, often nicknamed "deepfakes," have been the subject of sustained attention by legislators and technologists, but so far have not been employed to decisive effect, said two panelists at a video conference convened on Wednesday by NATO.

One speaker borrowed Sherlock Holmes' reasoning about the significance of something that didn't happen.

"We've already passed the stage at which they would have been most effective," said Keir Giles, a Russia specialist with the Conflict Studies Research Centre in the United Kingdom. "They're the dog that never barked."

The perils of deepfakes in political interference have been discussed too often and many people have become too familiar with them, Giles said during the online discussion, hosted by NATO's Strategic Communications Centre of Excellence.

Following all the reports and revelations about election interference in the West since 2016, citizens know too much to be hoodwinked in the way a fake video might once have fooled large numbers of people, he argued: "They no longer have the power to shock."

Tim Hwang, director of the Harvard-MIT Ethics and Governance of AI Initiative, agreed that deepfakes haven't proven as dangerous as once feared, although for different reasons.

Hwang argued that users of "active measures" (efforts to sow misinformation and influence public opinion) can be much more effective with cheaper, simpler and just as devious types of fakes — mis-captioning a photo or turning it into a meme, for example.

Influence specialists working for Russia and other governments also imitate Americans on Facebook, for another example, worming their way into real Americans' political activities to amplify disagreements or, in some cases, try to persuade people not to vote.

Other researchers have suggested this work continues on social networks and has become more difficult to detect.

Defense is stronger than attack

Hwang also observed that the more deepfakes are made, the better machine learning becomes at detecting them.

A very sophisticated, real-looking fake video might still be effective in a political context, he acknowledged — and at a cost to create of around $10,000, it would be easily within the means of a government's active measures specialists.

But the risks of attempting a major disruption with such a video may outweigh an adversary's desire to use one. People may be too media literate, as Giles argued, and the technology to detect a fake may mean it can be deflated too swiftly to have an effect, as Hwang said.

"I tend to be skeptical these will have a large-scale impact over time," he said.

One technology boss told NPR in an interview last year that years' worth of work on corporate fraud protection systems has given an edge to detecting fake media.

"This is not a static field. Obviously, on our end we've performed all sorts of great advances over this year in advancing our technology, but these synthetic voices are advancing at a rapid pace," said Brett Beranek, head of security business for the technology firm Nuance. "So we need to keep up."

Beranek described how systems developed to detect telephone fraudsters could be applied to verify the speech in a fake clip of video or audio.

Corporate clients that rely on telephone voice systems must be wary about people attempting to pose as others with artificial or disguised voices. Beranek's company sells a product that helps to detect them and that countermeasure also works well in detecting fake audio or video.

Machines using neural networks can detect known types of synthetic voices. Nuance also says it can analyze a recording of a real known voice — say, that of a politician — and then contrast its characteristics against a suspicious recording.

Although the world of cybersecurity is often described as one in which attackers generally have an edge over defenders, Beranek said he thought the inverse was true in terms of this kind of fraud detection.

"For the technology today, the defense side is significantly ahead of the attack side," he said.

Shaping the battlefield

Hwang and Giles acknowledged in the NATO video conference that deepfakes likely will proliferate and become lower in cost to create, perhaps becoming simple enough to make with a smartphone app.

One prospective response is the creation of more of what Hwang called "radioactive data" — material earmarked in advance so that it might make a fake easier to detect.

If images of a political figure were so tagged beforehand, they could be spotted quickly if they were incorporated by computers into a deceptive video.

Also, the sheer popularity of new fakes, if that is what happens, might make them less valuable as a disinformation weapon. More people could become more familiar with them, as well as being detectable by automated systems — plus they may also have no popular medium on which to spread.

Big social media platforms already have declared affirmatively that they'll take down deceptive fakes, Hwang observed. That might make it more difficult for a scenario in which a politically charged fake video went viral just before Election Day.

"Although it might get easier and easier to create deepfakes, a lot of the places where they might spread most effectively, your Facebooks and Twitters of the world, are getting a lot more aggressive about taking them down," Hwang said.

That won't stop them, but it might mean they'll be relegated to sites with too few users to have a major effect, he said.

"They'll percolate in these more shady areas."

This content is from Southern California Public Radio. View the original story at SCPR.org.

It was a new day at the Supreme Court, which for the first time ever live-streamed oral arguments.; Credit: Andrew Harnik/AP

The U.S. Supreme Court made history Monday. The coronavirus lockdown forced the typically cautious court to hear arguments for the first time via telephone, and to stream the arguments live for the public to hear.

Chief Justice John Roberts was at the court as the telephone session began, one or two other justices were in their offices at the court, and the rest of the justices dialed in from home.

The first and only case heard Monday involved an arcane trademark question only a lawyer could love. Online travel search engine Booking.com is appealing a U.S. Patent and Trademark Office refusal to grant a trademark to the company.

With the justices asking questions in order of seniority, the first big surprise was that Justice Clarence Thomas, who in the past has gone years without asking a question, did ask one, several in fact, when it came his turn.

"Could Booking acquire an 800 number ... that's a vanity number, 1-800-BOOKING, for example?" Thomas asked Assistant Solicitor General Erica Ross.

Yes, replied Ross, but domain names pose a different problem than phone numbers. Ultimately, she argued "the core problem with Booking.com is that it allows [Booking.com] to monopolize booking on the internet" to the exclusion of other sites like hotelbooking.com.

Justice Stephen Breyer followed up when his turn came: "Same question as Justice Thomas ... good morning, anyway ... You can have a trademark that's an address. You can have a trademark that's a telephone number. So why can't you have a trademark that's a dot-com?"

Justice Samuel Alito noted that the court's prior decision in this area of the law was more than 100 years old, and the statute dealing with trademarks was similarly enacted decades ago.

"How can a rule that makes sense in the internet age be reconciled with the language" in these "pre-Internet era" laws? asked Alito.

Next up to her lectern from her home was lawyer Lisa Blatt. This was her 40th Supreme Court argument and despite being a veteran, she said later that she was, as usual, sick to her stomach beforehand.

But once at the lectern "it's always a rush of excitement," she said, and this time it was a special rush.

"I loved getting a question from Justice Thomas ... I would go to the phone for the foreseeable future if I could get Justice Thomas to ask questions. That was wonderful," she said.

Indeed, despite the new format Blatt and Ross seemed to have had a good time.

"Your client would not object to the registration of any trademark that simply made a slight variation in Booking.com?" asked Alito.

"There's a million booking registrations already," parried Blatt.

Alito: "Would you just answer the question."

Blatt: "They don't and have not and would not."

Not, she added, unless another company ripped off the trademark with no variation. That would be theft, she said.

So, when when the argument was over, what was her reaction?

"After I hung up, I screamed, 'That was hard!' Because you're saying enough to answer, but not too much. And you don't have any like visual feedback, so it was hard."

In the end, she said, the argument felt more like an oral exam than an oral argument.

Tom Goldstein, publisher of Scotusblog, had a similar reaction. Goldstein, who has argued 43 cases before the court, said he thought the argument was probably more useful to the public than usual.

"But I bet it was less useful for the justices," he said. "Because there was less opportunity to follow up on lines of questions and less opportunity to influence someone ... so there's much less engagement in the oral argument."

Still there were no major hitches on this first day. Justice Sonia Sotomayor briefly forget to unmute her phone at one point, prompting a "Sorry, chief." Justice Breyer's voice broke up in static for a second or two. But as Goldstein observes, this was a big change for the court.

"Culturally a change, technologically a change. And it could have been a big embarrassment if it didn't go well, but it went fine," he said. "I think they're happy."

This content is from Southern California Public Radio. View the original story at SCPR.org.

The pandemic has highlighted the need for businesses to act with alacrity and prepare for the long haul – and to do so with cybersecurity in mind

The post Digital transformation could be accelerated by COVID‑19 appeared first on WeLiveSecurity

In a recent experiment in Norway, electrical appliance stores increased their sales of energy-efficient tumble driers when consumers were made aware of their cheaper lifetime operating costs by shop staff and a new product labelling system.

Building Information Modelling (BIM) can enhance the design of a building, reduce costs and save energy. However, little research has been carried out on its impact on sustainable practices. A US survey illustrates that many practitioners do not see sustainability as a primary application, suggesting that more effort is needed to encourage the integration of ‘green’ design and construction into BIM.

Public authorities in EU Member States are encouraged to purchase more environmentally-friendly goods and services through Green Public Procurement (GPP). A recent survey of purchasing managers in Italy has identified some factors that influence their adoption of this strategy, and suggests that a broad knowledge of GPP is key to its implementation.

Providing information to consumers on the environmental and social impacts of their food purchases could help change their consumption choices, research from Norway suggests. In a psychological study, researchers noted an increase in the number of organic and fair trade products bought per week when participating consumers were informed of the products’ benefits for the environment and the wellbeing of producers.

Simply supplying more scientific information on the environment may not be enough to persuade urban planners to give greater consideration to the environment, suggests new research. The Dutch study suggests that environmental values also need to be made more important to municipal decision makers.

New EU-funded research from Finland has indicated that poor communication between producers of energy-efficient housing technologies and potential house-buyers is a major barrier to sustainable housing. It suggests that government bodies can encourage energy-efficiency innovations not only through regulations but also by improving information flow.

In a recent experiment in Norway, electrical appliance stores increased their sales of energy-efficient tumble driers when consumers were made aware of their cheaper lifetime operating costs by shop staff and a new product labelling system.

A new oil-spill risk-management system has been developed by researchers, which shows the likely effects of a coastal spill on the environment and economic activities for specific locations. It provides maps of oil-spill risk through a web portal and could help decision makers and emergency-response authorities protect the local environment and businesses through targeted and efficient planning and responses.

Genpact sees over 100 clients closing their financial quarter digitally while others are doubling the pace of adoption of digital transformation.

The international University of California, Riverside-led SpARCS collaboration has discovered four of the most distant clusters of galaxies ever found, as they appeared when the universe was only 4 billion years old. Clusters are rare regions of the universe consisting of hundreds of galaxies containing trillions of stars, as well as hot gas and mysterious dark matter. Spectroscopic observations from the ground using the W. M. Keck Observatory in Hawaii and the Very Large Telescope in Chile confirmed the four candidates to be massive clusters. This sample is now providing the best measurement yet of when and how fast galaxy clusters stop forming stars in the early Universe.

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Informing consumers about their energy use and giving advice on how it can be improved can result in lower public energy consumption, new research suggests. However, if such information campaigns are based solely on monetary savings they are not effective, the study concludes.

One of the greatest challenges facing environmental policymakers is encouraging people to behave more sustainably. A recent study explores how 'nudging' people to make environmentally friendly choices, together with providing information, can be a successful combination for achieving behavioural change.

The Internet consumers are becoming more aware of their personal data and 82 per cent users have tried to remove private information from websites or social media channels, according to a report by cybersecurity firm Kaspersky.

Digital marketing is a particularly strong capability for Indian companies, according to the new global study by Infosys Knowledge Institute.

Geodiversity describes the diversity of the non-biological parts of the natural world such as rocks, soils, landforms and the processes which shape them over time. New research on how geodiversity information has been used to examine or inform conservation policy has been explored through eight different case studies. The research shows the variety and utility of geodiversity information to support biodiversity protection, both now and in the future.

Free-flowing rivers (FFRs) support a complex, dynamic and diverse range of global ecosystems, and provide important economic and societal services. However, infrastructure built to use these services — most notably 2.8 million dams worldwide — has caused many rivers to become fragmented and disconnected, affecting river biodiversity and ecosystem services. This study constructed a global information system with which to map the fine-scale dynamics and fragmentation of FFRs and to determine how human pressures affect the world’s river systems.

The public places a high value on the use of scientific information, especially regarding climate change, in the management of groundwater resources, a case study in Finland indicates. This suggests that incorporating scientific research into management policies is likely to have the support of stakeholders in the region.

I like to think of geometric transformations of images (stretching, shrinking, rotating, etc.) by starting with the geometric transformations of points. You could think of a geometric point transformation as just moving a point from one location to another, like this:... read more >>

Today I decided to revisit a topic I covered a few years ago: loading discrete signals in a simulation.... read more >>

CULPEPER — The Virginia Department of Transportation invites the public to attend a citizen information meeting to learn about the upcoming project...