C. Tintarev
St. Petersburg Math. J. 31 (2020), 421-434.
Abstract, references and article information

Yingxiang Hu and Shicheng Xu
Proc. Amer. Math. Soc. 148 (2020), 2609-2615.
Abstract, references and article information

Two short films have made it one step closer to an Oscar nomination after picking up a Light in Motion (LIM) award at the Foyle Film Festival’s closing ceremony in Brunswick Moviebowl.

All the details on Uber's biggest announcements as well as updates on the controversial company's trials and tribulations

About $31 million in funding has been given to support 79 projects under the special round of the Public Policy Research (PPR) Funding Scheme, the Government announced today.

A total of 210 applications were received for the special round, which was launched last November to fund local research institutions and think tanks to research topics relating to the underlying causes of the social incidents that took place in the second half of 2019.

The research may also cover important political, economic, cultural and societal issues relating to deep-seated problems of society.

Assessment of the applications received under the special round was conducted by the independent assessment panel chaired by and comprising experienced academics.

The research quality of the proposal and relevance to the themes of the special round were the principal assessment criteria, with consideration given to factors such as whether the research proposal was solution-oriented, feasible and practical, whether the methodology was reasonable and sound, the applicant’s capability and whether the proposed budget was cost-effective. 

The assessment panel took a holistic view on each research proposal, reached a collective decision and made recommendations, the Policy Innovation & Co-ordination Office said, adding that a declaration of interest system was in place to ensure the assessments were fair and impartial.

In general, a sum of up to $500,000 has been granted to each approved project under the special round.

The approved projects have commenced progressively and are expected to be completed by the end of the year, with the first batch to be completed in late September to early October.

Click here for details of the funded projects.

"Driverless cars, robot butlers and reusable rockets--if the big inventions of the past decade and the artificial intelligence developed to create them have taught us anything, it's that maths is undeniably cool. And if you’re still not convinced, chances are you’ve never had it explained to you via a live experiment with a pigeon before. Temporary pigeon handler and queen of making numbers fun is Dr Hannah Fry, the host of this year's annual Royal Institution Christmas Lectures." Learn more in "Christmas Lectures presenter Dr Hannah Fry on pigeons, AI and the awesome power of maths," by Rachael Pells, inews, December 23, 2019.

Purinergic signaling by extracellular ATP regulates a variety of cellular events and is implicated in both normal physiology and pathophysiology. Several molecules have been associated with the release of ATP and other small molecules, but their precise contributions have been difficult to assess because of their complexity and heterogeneity. Here, we report on the results of a gain-of-function screen for modulators of hypotonicity-induced ATP release using HEK-293 cells and murine cerebellar granule neurons, along with bioluminescence, calcium FLIPR, and short hairpin RNA–based gene-silencing assays. This screen utilized the most extensive genome-wide ORF collection to date, covering 90% of human, nonredundant, protein-encoding genes. We identified two ABCG1 (ABC subfamily G member 1) variants, which regulate cellular cholesterol, as modulators of hypotonicity-induced ATP release. We found that cholesterol levels control volume-regulated anion channel–dependent ATP release. These findings reveal novel mechanisms for the regulation of ATP release and volume-regulated anion channel activity and provide critical links among cellular status, cholesterol, and purinergic signaling.

T-type (Cav3) Ca2+ channels are important regulators of excitability and rhythmic activity of excitable cells. Among other voltage-gated Ca2+ channels, Cav3 channels are uniquely sensitive to oxidation and zinc. Using recombinant protein expression in HEK293 cells, patch clamp electrophysiology, site-directed mutagenesis, and homology modeling, we report here that modulation of Cav3.2 by redox agents and zinc is mediated by a unique extracellular module containing a high-affinity metal-binding site formed by the extracellular IS1–IS2 and IS3–IS4 loops of domain I and a cluster of extracellular cysteines in the IS1–IS2 loop. Patch clamp recording of recombinant Cav3.2 currents revealed that two cysteine-modifying agents, sodium (2-sulfonatoethyl) methanethiosulfonate (MTSES) and N-ethylmaleimide, as well as a reactive oxygen species–producing neuropeptide, substance P (SP), inhibit Cav3.2 current to similar degrees and that this inhibition is reversed by a reducing agent and a zinc chelator. Pre-application of MTSES prevented further SP-mediated current inhibition. Substitution of the zinc-binding residue His191 in Cav3.2 reduced the channel's sensitivity to MTSES, and introduction of the corresponding histidine into Cav3.1 sensitized it to MTSES. Removal of extracellular cysteines from the IS1–IS2 loop of Cav3.2 reduced its sensitivity to MTSES and SP. We hypothesize that oxidative modification of IS1–IS2 loop cysteines induces allosteric changes in the zinc-binding site of Cav3.2 so that it becomes sensitive to ambient zinc.

S-Palmitoylation is a reversible post-translational lipid modification that dynamically regulates protein functions. Voltage-gated sodium channels are subjected to S-palmitoylation and exhibit altered functions in different S-palmitoylation states. Our aim was to investigate whether and how S-palmitoylation regulates Nav1.6 channel function and to identify S-palmitoylation sites that can potentially be pharmacologically targeted. Acyl-biotin exchange assay showed that Nav1.6 is modified by S-palmitoylation in the mouse brain and in a Nav1.6 stable HEK 293 cell line. Using whole-cell voltage clamp, we discovered that enhancing S-palmitoylation with palmitic acid increases Nav1.6 current, whereas blocking S-palmitoylation with 2-bromopalmitate reduces Nav1.6 current and shifts the steady-state inactivation in the hyperpolarizing direction. Three S-palmitoylation sites (Cys1169, Cys1170, and Cys1978) were identified. These sites differentially modulate distinct Nav1.6 properties. Interestingly, Cys1978 is exclusive to Nav1.6 among all Nav isoforms and is evolutionally conserved in Nav1.6 among most species. Cys1978 S-palmitoylation regulates current amplitude uniquely in Nav1.6. Furthermore, we showed that eliminating S-palmitoylation at specific sites alters Nav1.6-mediated excitability in dorsal root ganglion neurons. Therefore, our study reveals S-palmitoylation as a potential isoform-specific mechanism to modulate Nav activity and neuronal excitability in physiological and diseased conditions.

Barttin is the accessory subunit of the human ClC-K chloride channels, which are expressed in both the kidney and inner ear. Barttin promotes trafficking of the complex it forms with ClC-K to the plasma membrane and is involved in activating this channel. Barttin undergoes post-translational palmitoylation that is essential for its functions, but the enzyme(s) catalyzing this post-translational modification is unknown. Here, we identified zinc finger DHHC-type containing 7 (DHHC7) protein as an important barttin palmitoyl acyltransferase, whose depletion affected barttin palmitoylation and ClC-K-barttin channel activation. We investigated the functional role of barttin palmitoylation in vivo in Zdhhc7−/− mice. Although palmitoylation of barttin in kidneys of Zdhhc7−/− animals was significantly decreased, it did not pathologically alter kidney structure and functions under physiological conditions. However, when Zdhhc7−/− mice were fed a low-salt diet, they developed hyponatremia and mild metabolic alkalosis, symptoms characteristic of human Bartter syndrome (BS) type IV. Of note, we also observed decreased palmitoylation of the disease-causing R8L barttin variant associated with human BS type IV. Our results indicate that dysregulated DHHC7-mediated barttin palmitoylation appears to play an important role in chloride channel dysfunction in certain BS variants, suggesting that targeting DHHC7 activity may offer a potential therapeutic strategy for reducing hypertension.

Non-residential and residential electricity accounts are benefitting from government relief measures, the Environmental Bureau announced today.

Under the measures, nearly 90% of non-residential electricity bills obtained a 75% subsidy for electricity charges in March, while 40% of residential electricity accounts enjoyed zero electricity charges in the first quarter of the year.

The Government announced about $2.3 billion in provisions last December to provide an electricity charge subsidy to each eligible non-residential electricity account holder to cover 75% of their monthly electricity charges for four months, subject to a monthly cap of $5,000.

The Budget further provided $2.9 billion to extend the subsidy period to eight months.

According to the bills issued by the two power companies in March, 360,000 non-residential bills obtained a 75% subsidy. This is close to 90% of the total eligible non-residential tariff bills.

To balance the impact on people's livelihood of the recent transition to cleaner electricity generating systems in Hong Kong, the bureau implemented the electricity charges relief scheme in January 2019.

A monthly electricity charge relief of $50 has been granted to each eligible residential electricity account for 60 months.

To help the public cope with the challenging economic environment, the Government implemented a new round of one-off electricity charge subsidy schemes in January.

A subsidy of $160 will be credited to each residential electricity account from January to November, while $240 will be credited in December.

From early this year, over 2.7 million households have been benefitting from both the electricity charges relief measures and the electricity charges subsidy. The bills of the two power companies indicated that 40% of residential electricity accounts, representing 1 million households, enjoyed zero electricity charges.

The bureau called on the community to cherish environmental resources, including saving energy and electricity to mitigate climate change and improve air quality.

(University of Barcelona) The yellow-legged gull has a high ability to adapt to human activities and benefit from these as a food resource during all year. This is stated in a scientific article published in the journal Ecology and Evolution whose first author is the researcher Francisco Ramírez, from the Faculty of Biology and the Biodiversity Research Institute (IRBio) of the University of Barcelona.

(International Astronomical Union) The Gruber Cosmology Prize, which is co-sponsored by the IAU, recognises scientists whose discoveries have driven fundamental advances in our understanding of the Universe. The 2020 prize has been awarded to Lars Hernquist and Volker Springel for their pioneering work on cosmological simulations, which have not only led to their own discoveries, but also become an invaluable resource used widely by other researchers.

(Boston University School of Medicine) A new Boston University School of Public Health (BUSPH) study published in the journal Environmental Research finds detectable levels of DDE (what DDT becomes when metabolized in the body) and other banned organochlorine pesticides (OCPs) in the blood of over 60 percent of a cohort of black women of reproductive age in the Detroit area, with higher levels in women who smoked cigarettes daily, drank more alcohol, and drank more water.

There is no special announcement (19:45 HKT on 03.05.2020)

(University of Southern Denmark) Investing in the future: Researchers show how cannibalism among the invasive comb jelly enables adults to survive severe conditions at the edge of their ecological range with implications for the use and evolutionary origins of cannibalism.

The budget carrier will begin conducting temperature checks via touchless thermometers on June 1. Passengers have to start wearing masks Friday.

Current regulations do not effectively prevent potentially misleading claims, says Imperial scientists

Imperial's disease outbreak centre J-IDEA has launched a pandemic hospital planning tool to help cope with extreme surges in demand from coronavirus.

(American Geriatrics Society) The American Geriatrics Society (AGS) will this year honor past AGS President Todd Semla, PharmD, MS, AGSF, with the prestigious Nascher/Manning Award, given biannually at the AGS Annual Scientific Meeting (#AGS21, to be held next year May 13-15 in Chicago, Ill., following the cancellation of the AGS 2020 Annual Scientific Meeting due to COVID-19).

(Crime and Justice Research Alliance) A new study evaluated the effects of legalizing cannabis on police officers' law enforcement efforts in Washington. The study found that officers in that state, although not supportive of recriminalization, had a variety of concerns, from worries about the effect on youth to increases in impaired driving. The study can inform other states' efforts to address legalization.

The Sanford C. Bernstein & Co. Center for Leadership and Ethics spoke with Anna Houseman '21 about her daily routine, personal ethics, and staying productive during the pandemic. 

Businesses will benefit from clear policy guidance from lawmakers

Research Event

Event participants

This event is now full and registration has closed.

Participants include

Zeinab Badawi, Presenter, BBC Global Questions and HardTalk
Lakhdar Brahimi, The Elders; Chair, Panel on United Nations Peace Operations (2000)
Alan Doss, President, Kofi Annan Foundation 
Raila Odinga, High Representative for Infrastructure Development, African Union; Prime Minister of Kenya (2008-13)
Patrick Gaspard, President, Open Society Foundations
Michèle Griffin, Senior Policy Advisor to the UN Secretary-General
Ian Martin, Special Representative of the UN Secretary-General in East Timor (1999), Nepal (2007-09) and Libya (2011-12)
Strive Masiyiwa, Chair of the Board, AGRA; CEO, Econet Wireless
Amina Mohammed, Deputy Secretary-General, United Nations
Kumi Naidoo, Secretary-General, Amnesty International
Danny Sriskandarajah, Chief Executive, Oxfam
Mark Suzman, Chief Strategy Officer and President of Global Policy and Advocacy, Bill & Melinda Gates Foundation

23 October 2019

The ‘Our Shared Humanity’ conference explored Kofi Annan’s legacy for the future of global governance in the run-up to the UN’s 75th anniversary. This paper summarizes key points raised during the conference, and presents the substantive recommendations that emerged from the discussion.

Xien Yu Chua
Apr 1, 2020; 19:730-743
Technological Innovation and Resources

Dynamic tyrosine phosphorylation is fundamental to a myriad of cellular processes. However, the inherently low abundance of tyrosine phosphorylation in the proteome and the inefficient enrichment of phosphotyrosine(pTyr)-containing peptides has led to poor pTyr peptide identification and quantitation, critically hindering researchers' ability to elucidate signaling pathways regulated by tyrosine phosphorylation in systems where cellular material is limited. The most popular approaches to wide-scale characterization of the tyrosine phosphoproteome use pTyr enrichment with pan-specific, anti-pTyr antibodies from a large amount of starting material. Methods that decrease the amount of starting material and increase the characterization depth of the tyrosine phosphoproteome while maintaining quantitative accuracy and precision would enable the discovery of tyrosine phosphorylation networks in rarer cell populations. To achieve these goals, the BOOST (Broad-spectrum Optimization Of Selective Triggering) method leveraging the multiplexing capability of tandem mass tags (TMT) and the use of pervanadate (PV) boost channels (cells treated with the broad-spectrum tyrosine phosphatase inhibitor PV) selectively increased the relative abundance of pTyr-containing peptides. After PV boost channels facilitated selective fragmentation of pTyr-containing peptides, TMT reporter ions delivered accurate quantitation of each peptide for the experimental samples while the quantitation from PV boost channels was ignored. This method yielded up to 6.3-fold boost in pTyr quantification depth of statistically significant data derived from contrived ratios, compared with TMT without PV boost channels or intensity-based label-free (LF) quantitation while maintaining quantitative accuracy and precision, allowing quantitation of over 2300 unique pTyr peptides from only 1 mg of T cell receptor-stimulated Jurkat T cells. The BOOST strategy can potentially be applied in analyses of other post-translational modifications where treatments that broadly elevate the levels of those modifications across the proteome are available.