The coronavirus lockdown has separated many of us from our families, including our mothers. However, Sophie Choudhry is one lucky celeb who is able to spend her quarantine and Mothers' Day with her supermom. In fact, she told us all about her plans for the day.

The UT excise and taxation department has extended the excise policy from May 15 to June 30 due to the Covid-19 pandemic and the ongoing lockdown.

Instances of crystal structures that remain isomorphous in spite of some minor changes in their respective mol­ecules, such as change in a substituent atom/group, can provide insights into the factors that govern crystal packing. In this context, an accurate description of the crystal structures of an isomorphous pair that differ from each other only by a chlorine–methyl substituent, viz. 5''-(2-chloro­benzyl­idene)-4'-(2-chloro­phen­yl)-1'-methyl­dispiro­[acenaphthene-1,2'-pyrrolidine-3',3''-piperidine]-2,4''-dione, C34H28Cl2N2O2, (I), and its analogue 1'-methyl-5''-(2-methyl­benzyl­idene)-4'-(2-methyl­phen­yl)di­spiro­[acenaphthene-1,2'-pyrrolidine-3',3''-piperidine]-2,4''-dione, C36H34N2O2, (II), is presented. While there are two C—H⋯O weak inter­molecular inter­actions present in both (I) and (II), the change of substituent from chlorine to methyl has given rise to an additional weak C—H⋯O inter­molecular inter­action that is relatively stronger than the other two. However, the presence of the stronger C—H⋯O inter­action in (II) has not disrupted the validity of the chloro-methyl exchange rule. Details of the crystal structures and Hirshfeld analyses of the two compounds are presented.

Human carbonic anhydrase IX (CA IX) expression is upregulated in hypoxic solid tumours, promoting cell survival and metastasis. This observation has made CA IX a target for the development of CA isoform-selective inhibitors. To enable structural studies of CA IX–inhibitor complexes using X-ray and neutron crystallography, a CA IX surface variant (CA IXSV; the catalytic domain with six surface amino-acid substitutions) has been developed that can be routinely crystallized. Here, the preparation of protiated (H/H), H/D-exchanged (H/D) and deuterated (D/D) CA IXSV for crystallographic studies and their structural comparison are described. Four CA IXSV X-ray crystal structures are compared: two H/H crystal forms, an H/D crystal form and a D/D crystal form. The overall active-site organization in each version is essentially the same, with only minor positional changes in active-site solvent, which may be owing to deuteration and/or resolution differences. Analysis of the crystal unit-cell packing reveals different crystallographic and noncrystallographic dimers of CA IXSV compared with previous reports. To our knowledge, this is the first report comparing three different deuterium-labelled crystal structures of the same protein, marking an important step in validating the active-site structure of CA IXSV for neutron protein crystallography.

Reducing the sample-exchange time is a crucial issue in maximizing the throughput of macromolecular crystallography (MX) beamlines because the diffraction data collection itself is completed within a minute in the era of pixel-array detectors. To this end, an upgraded sample changer, SPACE-II, has been developed on the basis of the previous model, SPACE (SPring-8 Precise Automatic Cryo-sample Exchanger), at the BL41XU beamline at SPring-8. SPACE-II achieves one sample-exchange step within 16 s, of which its action accounts for only 11 s, because of three features: (i) the implementation of twin arms that enable samples to be exchanged in one cycle of mount-arm action, (ii) the implementation of long-stroke mount arms that allow samples to be exchanged without withdrawal of the detector and (iii) the use of a fast-moving translation and rotation stage for the mount arms. By pre-holding the next sample prior to the sample-exchange sequence, the time was further decreased to 11 s in the case of automatic data collection, of which the action of SPACE-II accounted for 8 s. Moreover, the sample capacity was expanded from four to eight Uni-Pucks. The performance of SPACE-II has been demonstrated in over two years of operation at BL41XU; the average number of samples mounted on the diffractometer in one day was increased from 132 to 185, with an error rate of 0.089%, which counted incidents in which users could not continue with an experiment without recovery work by entering the experimental hutch. On the basis of these results, SPACE-II has been installed at three other MX beamlines at SPring-8 as of July 2019. The fast and highly reliable SPACE-II is now one of the most important pieces of infrastructure for the MX beamlines at SPring-8, providing users with the opportunity to fully make use of limited beamtime with brilliant X-rays.

Enhancement of X-ray excited optical luminescence in a 100 µm-thick diamond plate by introduction of defect states via electron beam irradiation and subsequent high-temperature annealing is demonstrated. The resulting X-ray transmission-mode scintillator features a linear response to incident photon flux in the range 7.6 × 108 to 1.26 × 1012 photons s−1 mm−2 for hard X-rays (15.9 keV) using exposure times from 0.01 to 5 s. These characteristics enable a real-time transmission-mode imaging of X-ray photon flux density without disruption of X-ray instrument operation.

Quantum beats in fluorescence decay from Zeeman-split magnetic sublevels have been measured for helium Rydberg states excited by synchrotron radiation. The Zeeman quantum beats observed in this prototypical case were fitted with an equation from a theoretical formulation. It is proposed that Zeeman quantum beat measurement can be a useful way to simply evaluate the polarization characteristics of extreme ultraviolet light.

Neutron crystal structure analysis of hen egg-white lysozyme hydrogen/deuterium exchanged before crystallization were performed by the joint X-ray and neutron refinement. The differences in hydrogen/deuterium exchange behavior between this study and previous ones were observed.

The fossil teeth of a 15- to 18-million-year-old three-toed browsing horse, Anchitherium clarencei, were recently discovered by scientists from the Smithsonian Tropical Research Institute and the […]

The post Fossil teeth of 15-million-year-old browsing horse found in Panama Canal excavations. appeared first on Smithsonian Insider.

A scientist from the Smithsonian Tropical Research Institute uses a pick to dislodge the fossil skull of an extinct toothed whale from sediments on the […]

The post Fossil skull of an extinct toothed whale excavated from Panamanian sediments appeared first on Smithsonian Insider.

The discovery of two new extinct camel species by scientists from the University of Florida and the Smithsonian is casting new light on the history of the tropics, a region containing more than half the world's biodiversity and some of its most important ecosystems.

The post Two new species of extinct camels discovered in Panama Canal excavations appeared first on Smithsonian Insider.

Seven fossil teeth exposed by the Panama Canal expansion project are the first evidence of a monkey on the North American continent before the Isthmus […]

The post First North American Monkey Fossils Found in Panama Canal Excavation appeared first on Smithsonian Insider.

Olga Kopach, Noemi Esteras, Selina Wray, Dmitri A. Rusakov, and Andrey Y. Abramov

Frontotemporal dementia and parkinsonism (FTDP-17) caused by the 10+16 splice-site mutation in the MAPT provides an established platform to model tau-related dementia in vitro. Human iPSC-derived neurons have been shown to recapitulate the neurodevelopmental profile of tau pathology during in vitro corticogenesis as in the adult human brain. However, the neurophysiological phenotype of these cells has remained unknown, leaving unanswered questions over the functional relevance and the gnostic power of this disease model. Here we used electrophysiology to explore the membrane properties and intrinsic excitability of the generated neurons to find that human cells mature by ~150 days of neurogenesis to become compatible with matured cortical neurons. In earlier FTDP-17, neurons, however, exhibited a depolarized resting membrane potential associated with increased resistance and reduced voltage-gated Na⁺- and K⁺-channel-mediated conductance. The Na_v1.6 protein was reduced in FTDP-17. These led to a reduced cell capability of induced firing and changed action potential waveform in FTDP-17. The revealed neuropathology may thus contribute to the clinicopathological profile of the disease. This sheds new light on the significance of human models of dementia in vitro.

Miniature camels and horses, a rhinoceros and a giant bear-dog are among fossils unearthed in the recent excavations of the Panama Canal expansion project. These […]

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Two grass species that had been relatively rare in the plots, Spartina patens and Distichlis spicata, began to respond vigorously to the excess nitrogen. Eventually the grasses became much more abundant. Nitrogen ultimately changed the composition of the ecosystem as well as its capacity to store carbon.

The post Scientists find excess nitrogen favors plants that respond poorly to rising CO2 appeared first on Smithsonian Insider.

Millions, if not billions, of specimens reside in the world’s natural history collections, but most of these have not been carefully studied, or even looked […]

The post Using digitized Botany specimens, AI excels in simple curatorial tasks appeared first on Smithsonian Insider.

Most Americans and Canadians up to age 70 need no more than 600 international units (IUs) of vitamin D per day to maintain health, and those 71 and older may need as much as 800 IUs, says a new report from the Institute of Medicine.

Data from studies monitoring the amount of plastic eaten by seabirds suggest that levels in the North Sea are well above targets established for the North East Atlantic Ocean by OSPAR (the Oslo and Paris Convention). For the most recent monitoring period, the target amount was exceeded in well over half the birds studied.

Effective ‘knowledge exchange’ - the process of producing, sharing, understanding and using knowledge - is vital to good environmental management. New research has uncovered five principles for this process which could help researchers, decision makers and other parties work together to better manage environmental change.

Wind and solar energy are effectively limitless resources, but construction of renewable power must compete for a finite amount of land. This study uses a constrained assessment of available land to see whether global energy demand could be fully met by renewable sources. The analysis predicts that by 2070, the world could produce between 730 and 3700 exajoules of electricity per year (EJ/a1) from renewable power, which, even at lowest available land estimates, could meet 2070 electricity needs in most countries.

Each person in the EU consumes the equivalent of 30% more global arable land than can be considered sustainable, according to a new study. As well as providing food for a growing population, the land is also increasingly used to grow biofuel crops.

The world could experience the highest ever global sea-level rise in the history of human civilisation if global temperature rises exceed 2 °C, predicts a new study. Under current carbon-emission rates, this temperature rise will occur around the middle of this century, with damaging effects on coastal businesses and ecosystems, while also triggering major human migration from low-lying areas. Global sea-level rise will not be uniform, and will differ for different points of the globe.

Civilisation has crossed four of nine ‘planetary boundaries’, increasing the risk of irreversibly driving the Earth in to a less hospitable state, concludes new research. These are: extinction rate, deforestation, atmospheric CO2 and the flow of nitrogen and phosphorus.

Levels of toxic metals in batteries were not immediately reduced in line with new limits imposed by EU regulations, according to a survey from Germany. The study focuses on concentrations of toxic metals contained in batteries sold in Germany in 2010 and 2011, but its authors say the results are relevant to other EU countries.

Levels of aquaculture pesticides exceed UK environmental quality standards (EQSs) in samples taken from near Norwegian fish farms, a recent study has shown. The researchers examined five pesticides used to kill sea lice (Lepeophtheirus salmonis) and showed that in many cases their concentrations exceeded UK EQSs. They used UK standards, they explain, because there are currently no Norwegian EQSs for these chemicals, and call for international quality standards to be drawn up.

The nitrogen dioxides (NOX) and carbon dioxide (CO2) emissions of some light-duty petrol and diesel vehicles are higher during on-road driving than during standard laboratory tests, according to a new study. This means that in normal on-road driving, light-duty vehicles, which include passenger cars and light commercial vehicles, may exceed European emissions limits and could be having a greater impact on urban air quality than previously thought.

More Europeans are driving diesel cars, with important implications for vehicle emissions. A new study suggests that diesel cars may emit nitrogen oxides (NOx) at levels far higher than emissions standards, even when considering the newest generation of diesel cars. Part of the problem is that tests of vehicle emissions in the laboratory do not accurately reflect on-road emissions.

Mercury levels in bream (Abramis brama) collected from six European sampling sites from 2007 to 2013 exceeded the Water Framework Directive’s safety limit for fish in all but one site in 2012, a new study discovers. The findings suggest greater efforts need to be made to prevent mercury pollution.

Air quality standards worldwide are facing increasing scrutiny as countries struggle to meet World Health Organisation (WHO) air-quality guidelines (AQGs), particularly regarding ozone (O₃) and particulate matter (pollutant particles with diameters of less than 10 or 2.5 micrometres — PM₁₀ and PM_2.5 respectively). A new study aimed to evaluate whether WHO guidelines are being met in Europe; the researchers focused on Portugal, using recent data alongside climate change and background air pollution predictions. At present, Portugal frequently exceeds legislated values for ozone and PM₁₀.

In order to manage its environmental footprint, Switzerland should act on a number of key issues identified by the ‘planetary boundaries’ framework, says a Swiss study, with priority given to the areas of climate change, ocean acidification, biodiversity loss and nitrogen loss. This quantitative framework identifies nine bio-physical limits of the Earth system that, if exceeded, may lead to societal and ecological changes unfavourable to human development and stability. These are upper thresholds rather than targets. The researchers suggest that the concept and their methodology could be used together to think differently about environmental issues, and change the way related assessments and policies are implemented at both global and national levels.

A new show, featuring incredible experiments from the world of science, is coming to Harpenden Public Halls this Easter.

While most NTU exchange students pick up local languages such as Chinese and Malay, a growing number from Western countries have over the past few years opted for European languages....

Oil snapped a three-day gain as exchange-traded funds avoided nearer-term contracts.

Paul Scott sells Nissan Leafs for a living. He put up his retirement savings for a few minutes with the president to talk about EVs and climate change.

Robots need to be tailored made for their nuclear plants, and the Fukushima plant was built prior to the adoption of robots.

The wunderkind behind the battery-powered car revolution chats with MNN about his company's future.

New EPA ruling on infilling valleys may limit future mountaintop mining permits, but it's only the first step in a long process to stop the 'Appalachian Apocaly

Felines, both heroic and villainous, play prominent roles in these 9 whisker-heavy horror films.

Tour a "top-of-the-line" 1970s RV inhabited by a recovering shopaholic who has given up the garage sales for a simpler life that's not dictated by stuff.

Launching of the Dragon capsule will mark a significant step forward in the partnership between NASA and the private sector.

Websites that end with .organic will go through a verification process before they can go live.

The COOKI, a stir-frying robot wonder machine, could be the kind of robot that makes real sense in our homes.

In 1984, the World Health Organization published a report determining the cause of sick building syndrome, in which the cumulative effects of bad ventilation, V

Despite anti-discrimination laws, some employers are still finding ways to cut ties with their pregnant employees.

From animals and architecture to treasures and wild weather, these are the shows we’ll be watching this month.