Telehealth and GP service Babylon has rolled out a "COVID-19 Care Assistant" with a raft of features designed to help subscribers cope with symptoms during the pandemic, from the safety of their phone screen

Health startups are being corralled by the NHS and the government to point their talents at the COVID-19 pandemic, while others are volunteering services to help stymie the spread of the infectious new disease

N. N. Leonenko, I. Papić, A. Sikorskii and N. Šuvak
Theor. Probability and Math. Statist. 99 (2020), 137-147.
Abstract, references and article information

Phạm Tiến Sơn
Proc. Amer. Math. Soc. 148 (2020), 2739-2741.
Abstract, references and article information

Alexander J. Rasmussen
Proc. Amer. Math. Soc. 148 (2020), 2345-2357.
Abstract, references and article information

The confidence level of Hong Kong’s exporters has fallen to its lowest-ever level in the face of a triple challenge – the COVID-19 outbreak, softening global demand and lingering trade tension between the United States and Mainland...

Here is some insight into the first ever blockchain advert

A group of technologists has led crowdsourcing efforts to create a single repository of information for specialists fighting the Coronavirus outbreak. Techworld speaks with founder Edward Saperia to hear more about how collaboration tools can help the efforts

The 'unicorn letter', sent by some of the best-funded private technology companies in the country, asks the chancellor to form an urgent taskforce to give them access to government-backed lending schemes during the pandemic

VOLUME 285 (2010) PAGES 13742–13747In Fig. 1E, passage 10, the splicing of a non-adjacent lane from the same immunoblot was not marked. This error has now been corrected and does not affect the results or conclusions of this work.jbc;295/16/5533/F1F1F1Figure 1E.

Extracytoplasmic sugar decoration of glycopolymer components of the bacterial cell wall contributes to their structural diversity. Typically, the molecular mechanism that underpins such a decoration process involves a three-component glycosylation system (TGS) represented by an undecaprenyl-phosphate (Und-P) sugar-activating glycosyltransferase (Und-P GT), a flippase, and a polytopic glycosyltransferase (PolM GT) dedicated to attaching sugar residues to a specific glycopolymer. Here, using bioinformatic analyses, CRISPR-assisted recombineering, structural analysis of cell wall–associated polysaccharides (CWPS) through MALDI-TOF MS and methylation analysis, we report on three such systems in the bacterium Lactococcus lactis. On the basis of sequence similarities, we first identified three gene pairs, csdAB, csdCD, and csdEF, each encoding an Und-P GT and a PolM GT, as potential TGS component candidates. Our experimental results show that csdAB and csdCD are involved in Glc side-chain addition on the CWPS components rhamnan and polysaccharide pellicle (PSP), respectively, whereas csdEF plays a role in galactosylation of lipoteichoic acid (LTA). We also identified a potential flippase encoded in the L. lactis genome (llnz_02975, cflA) and confirmed that it participates in the glycosylation of the three cell wall glycopolymers rhamnan, PSP, and LTA, thus indicating that its function is shared by the three TGSs. Finally, we observed that glucosylation of both rhamnan and PSP can increase resistance to bacteriophage predation and that LTA galactosylation alters L. lactis resistance to bacteriocin.

VOLUME 295 (2020) PAGES 3285–3300An incorrect graph was used in Fig. 5C. This error has now been corrected. Additionally, some of the statistics reported in the legend and text referring to Fig. 5C were incorrect. The F statistics for Fig. 5C should state Fken(3,16) = 7.454, p < 0.01; FCCCP(1,16) = 102.9, p < 0.0001; Finteraction(3,16) = 7.480, p < 0.01. This correction does not affect the results or conclusions of this work.jbc;295/17/5835/F5F1F5Figure 5C.

VOLUME 294 (2019) PAGES 2555–2568Due to publisher error, “150 l/mm” was changed to “150 liters/mm” in the second paragraph of the “Vibrational spectroscopy of samples” section under “Experimental Procedures.” The correct phrase should be “150 l/mm.”

VOLUME 295 (2020) PAGES 1898–1914Yichen Zhong's name was misspelled. The correct spelling is shown above.

Pathogenic bacteria of the genera Mycobacterium and Corynebacterium cause severe human diseases such as tuberculosis (Mycobacterium tuberculosis) and diphtheria (Corynebacterium diphtheriae). The cells of these species are surrounded by protective cell walls rich in long-chain mycolic acids. These fatty acids are conjugated to the disaccharide trehalose on the cytoplasmic side of the bacterial cell membrane. They are then transported across the membrane to the periplasm where they act as donors for other reactions. We have previously shown that transient acetylation of the glycolipid trehalose monohydroxycorynomycolate (hTMCM) enables its efficient transport to the periplasm in Corynebacterium glutamicum and that acetylation is mediated by the membrane protein TmaT. Here, we show that a putative methyltransferase, encoded at the same genetic locus as TmaT, is also required for optimal hTMCM transport. Deletion of the C. glutamicum gene NCgl2764 (Rv0224c in M. tuberculosis) abolished acetyltrehalose monocorynomycolate (AcTMCM) synthesis, leading to accumulation of hTMCM in the inner membrane and delaying its conversion to trehalose dihydroxycorynomycolate (h2TDCM). Complementation with NCgl2764 normalized turnover of hTMCM to h2TDCM. In contrast, complementation with NCgl2764 derivatives mutated at residues essential for methyltransferase activity failed to rectify the defect, suggesting that NCgl2764/Rv0224c encodes a methyltransferase, designated here as MtrP. Comprehensive analyses of the individual mtrP and tmaT mutants and of a double mutant revealed strikingly similar changes across several lipid classes compared with WT bacteria. These findings indicate that both MtrP and TmaT have nonredundant roles in regulating AcTMCM synthesis, revealing additional complexity in the regulation of trehalose mycolate transport in the Corynebacterineae.

Nucleoside analogues are a valuable experimental tool. Incorporation of these molecules into newly synthesized DNA (i.e. pulse-labeling) is used to monitor cell proliferation or to isolate nascent DNA. Some of the most common nucleoside analogues used for pulse-labeling of DNA in cells are the deoxypyrimidine analogues 5-ethynyl-2'-deoxyuridine (EdU) and 5-ethynyl-2'-deoxycytidine (EdC). Click chemistry enables conjugation of an azide molecule tagged with a fluorescent dye or biotin to the alkyne of the analog, which can then be used to detect incorporation of EdU and EdC into DNA. The use of EdC is often recommended because of the potential cytotoxicity associated with EdU during longer incubations. Here, by comparing the relative incorporation efficiencies of EdU and EdC during short 30-min pulses, we demonstrate significantly lower incorporation of EdC than of EdU in noninfected human fibroblast cells or in cells infected with either human cytomegalovirus or Kaposi's sarcoma-associated herpesvirus. Interestingly, cells infected with herpes simplex virus type-1 (HSV-1) incorporated EdC and EdU at similar levels during short pulses. Of note, exogenous expression of HSV-1 thymidine kinase increased the incorporation efficiency of EdC. These results highlight the limitations when using substituted pyrimidine analogues in pulse-labeling and suggest that EdU is the preferable nucleoside analogue for short pulse-labeling experiments, resulting in increased recovery and sensitivity for downstream applications. This is an important discovery that may help to better characterize the biochemical properties of different nucleoside analogues with a given kinase, ultimately leading to significant differences in labeling efficiency of nascent DNA.

The ribosome biogenesis factor Las1 is an essential endoribonuclease that is well-conserved across eukaryotes and a newly established member of the higher eukaryotes and prokaryotes nucleotide-binding (HEPN) domain-containing nuclease family. HEPN nucleases participate in diverse RNA cleavage pathways and share a short HEPN nuclease motif (RφXXXH) important for RNA cleavage. Most HEPN nucleases participate in stress-activated RNA cleavage pathways; Las1 plays a fundamental role in processing pre-rRNA. Underscoring the significance of Las1 function in the cell, mutations in the human LAS1L (LAS1-like) gene have been associated with neurological dysfunction. Two juxtaposed HEPN nuclease motifs create Las1's composite nuclease active site, but the roles of the individual HEPN motif residues are poorly defined. Here using a combination of in vivo experiments in Saccharomyces cerevisiae and in vitro assays, we show that both HEPN nuclease motifs are required for Las1 nuclease activity and fidelity. Through in-depth sequence analysis and systematic mutagenesis, we determined the consensus HEPN motif in the Las1 subfamily and uncovered its canonical and specialized elements. Using reconstituted Las1 HEPN-HEPN' chimeras, we defined the molecular requirements for RNA cleavage. Intriguingly, both copies of the Las1 HEPN motif were important for nuclease function, revealing that both HEPN motifs participate in coordinating the RNA within the Las1 active site. We also established that conformational flexibility of the two HEPN domains is important for proper nuclease function. The results of our work reveal critical information about how dual HEPN domains come together to drive Las1-mediated RNA cleavage.

(American Chemical Society) The COVID-19 pandemic has scientists considering a few less-conventional options while vaccines against SARS-CoV-2 are being developed. One option might be the oral polio vaccine. We chatted with one of the researchers proposing the idea -- Robert Gallo, M.D. -- to understand why a vaccine that hasn't been used in the U.S. for two decades might provide short-term protection against this new coronavirus: https://youtu.be/Wqw4aX4c33c.

With the northeast monsoon over southern China being generally weaker than normal for most of the time in March, the month was much warmer than usual, the Hong Kong Observatory said today.

The monthly mean temperature was 21.3 degrees Celsius, 2.2 degrees above normal and the mean minimum temperature was 19.7 degrees Celsius, 2.5 degrees above average. Both were the joint second highest on record for March.

The monthly mean maximum temperature was 23.8 degrees Celsius, 2.4 degrees above normal and the fifth highest on record for the month.

The month was also drier than usual with a total rainfall of 41.3mm, about half of the normal figure.

The accumulated rainfall recorded in the first three months of the year was 135.9mm, about 16% below average.

With the northeast monsoon over southern China being stronger than normal in April, the month was slightly cooler than usual, the Hong Kong Observatory said today.

The monthly mean temperature was 22 degrees Celsius, 0.6 degrees below normal.

The mean minimum temperature was 20 degrees Celsius, 0.8 degrees below average, while the monthly mean maximum temperature was 25.1 degrees Celsius, 0.1 degrees above normal.

The month was also drier than usual with a total rainfall of 77.8mm, about 55% below the normal figure.

The accumulated rainfall recorded in the first four months of the year was 213.7mm, about 36% below average.

(American Chemical Society) Antiviral drugs could help us fight the new coronavirus, but currently, we don't have a highly potent, effective antiviral that cures COVID-19. Why not? We called a few virologists to find out: https://youtu.be/AIpeZDR9i3E.

(University of Warwick) Warm winter spells have increased in frequency and duration two- to three times over since 1878, according to scientists led by the University of Warwick.

(Smithsonian Tropical Research Institute) Oil pollution is known to cause lethal and sublethal responses on coral communities in the short-term, but its long-term effects have not been widely studied. The Bahia Las Minas oil spill, which contaminated about 40 square kilometers (about 15 square miles) near the Smithsonian's Galeta Point Marine Laboratory in Colon and became the largest recorded near coastal habitats in Panama, served as an opportunity to understand how coral reefs in tropical ecosystems recover from acute contamination over time.

(American Chemical Society) When a dead body is found, one of the first things a forensic pathologist tries to do is estimate the time of death. There are several ways to do this, including measuring body temperature or observing insect activity, but these methods don't always work for corpses found in water. Now, researchers are reporting a mouse study in ACS' Journal of Proteome Research showing that certain proteins in bones could be used for this determination.

China reported one new coronavirus case for Friday, unchanged from the day before, data from the national health authority showed on Saturday. One new imported case was recorded on May 8, the National Health Commission said in a statement.

Chief Justice Patience Roggensack faced backlash for her comment, with some people calling it "elitist" to separate meatpackers from "regular folks."

Mikheil Saakashvili, the former president of Georgia, vowed on Friday to help his new boss, Ukrainian President Volodymyr Zelenskiy, clean out a political "swamp" of oligarchs' interests that he said were preventing Ukraine prospering. Twice president of Georgia, Saakashvili had a brief but stormy spell in Ukrainian politics five years ago under Zelenskiy's predecessor Petro Poroshenko in which he once clambered onto a roof to avoid law enforcement.

Now Swain, 40, spends her evenings having dinner with her girls, age 5 and 8, and studying for her real-estate license, which she hopes will provide more long-term stability for her family after the coronavirus crisis upended her livelihood. "I can't be put in a position like this again," said Swain, a bartender for 20 years. American women are taking an outsized hit from the early wave of unemployment caused by the pandemic, due to the nature of the jobs that were lost in the business shutdowns to control the spread of the coronavirus.

(Rutgers University) Rutgers' RUCDR Infinite Biologics received an amended emergency use authorization from the FDA late Thursday for the first SARS-CoV-2 coronavirus test that will allow people to collect their own saliva at home and send to a lab for results. The decision follows the FDA's recent emergency approval to RUCDR Infinite Biologics for the first saliva-based test, which involves health care workers collecting saliva from individuals at testing sites.

As part of the College's move to remote learning, 143 first-year students are taking a series of virtual field courses to investigate biodiversity.

A coronavirus test – which aims to deliver rapid results – has received major funding.