bluuebunny/crossref_metadata_2025 huggingface dataset:
Smoke-suppressant and flame-retardant rigid polyurethane foam obtained via processing based on saccharomycetes fungus and ammonium molybdate
Authors: Zhang Wei , Zhao Zidong , Lei Yun , Cui Yong , Li Xuetian
Published: December 2020

The present work proposes an environmentally friendly, simple, and efficient way to impart smoke suppression and flame retardancy to rigid polyurethane foam (RPUF) by soaking the pristine RPUF for short periods in the saccharomycetes fungus (SF) solution and then in the ammonium molybdate (AM) solution. The co-addition of SF and AM exhibit good performance on smoke suppression and flame retardant. The level of flammability, thermal degradation behavior, and combustion properties of the samples are evaluated mainly via vertical burning tests, thermogravimetric analysis, and calorimetry, respectively. The proportions of 16SF/3AM/RPUF are varied to maximize the performance of the processed RPUF samples in terms of both smoke suppression and flame retardancy, which are substantially increased by the optimal sample compared to those of pristine RPUF.
Noise-tolerant quantum speedups in quantum annealing without fine tuning
Authors: Kapit Eliot , Oganesyan Vadim
Published: December 2020

Quantum annealing is a powerful alternative model of quantum computing, which can succeed in the presence of environmental noise even without error correction. However, despite great effort, no conclusive demonstration of a quantum speedup (relative to state of the art classical algorithms) has been shown for these systems, and rigorous theoretical proofs of a quantum advantage (such as the adiabatic formulation of Grover’s search problem) generally rely on exponential precision in at least some aspects of the system, an unphysical resource guaranteed to be scrambled by experimental uncertainties and random noise. In this work, we propose a new variant of quantum annealing, called RFQA, which can maintain a scalable quantum speedup in the face of noise and modest control precision. Specifically, we consider a modification of flux qubit-based quantum annealing which includes low-frequency oscillations in the directions of the transverse field terms as the system evolves. We show that this method produces a quantum speedup for finding ground states in the Grover problem and quantum random energy model, and thus should be widely applicable to other hard optimization problems which can be formulated as quantum spin glasses. Further, we explore three realistic noise channels and show that the speedup from RFQA is resilient to 1/f-like local potential fluctuations and local heating from interaction with a sufficiently low temperature bath. Another noise channel, bath-assisted quantum cooling transitions, actually accelerates the algorithm and may outweigh the negative effects of the others. We also detail how RFQA may be implemented experimentally with current technology.
Coherent control with user-defined passage
Authors: Liu Bao-Jie , Yung Man-Hong
Published: December 2020

Stimulated Raman adiabatic passage (STIRAP) is a standard technique to combat experimental imperfections and can be used to realize robust quantum state control, which has many applications in physics, chemistry, and beyond. However, STIRAP is susceptible to decoherence since it requires long evolution time. To overcome this problem, stimulated Raman ‘user-defined’ passage (STIRUP) is proposed, which allows users to design the passages unlike the STIRAP but fast and robust against both decoherence and experimental imperfections. Here, we further develop a more general STIRUP method. Comparing with shortcut to adiabaticity and its’ variants, the generalized STIRUP is more simpler and compatible with more complex energy-level structure and many-body systems. Furthermore, the generalized STIRUP has many important applications such as geometric phase measurement, coherent population transfer, and quantum state preparation. Specifically, as examples, we show how to realize the high-fidelity quantum state transfer and entangled state generation in a robust way via STIRUP with the state-of-the-art experimental superconducting circuits.
Instrumentation for tracking electrochemical reactions by x-ray photoelectron spectroscopy under conventional vacuum conditions
Authors: Endo Raimu , Ohnishi Tsuyoshi , Takada Kazunori , Masuda Takuya
Published: December 2020

A bias application system for tracking electrochemical reactions by x-ray photoelectron spectroscopy (XPS) is constructed using a laboratory-based apparatus. A specialized sample holder and stage with three electrical terminals provide contacts to a potentio-galvanostat on the outside, allowing bias application to an electrochemical device in the analysis chamber under vacuum conditions. The application of a direct current bias voltage to the sample holder is confirmed using metal Au samples. The Au 4f peaks from the Au grounded to the analyzer are identical, while those from the Au insulated from the analyzer shift due to the applied bias voltage. Furthermore, galvanostatic lithiation/delithiation processes and in situ XPS measurements are performed on a Si thin-film electrode after transferring the sample into the XPS apparatus without exposure to open air using a newly developed transfer vessel. After the initial lithiation process, a Li 1s peak containing a lithium-silicide component appears, and the Si 2p peaks shift to a lower binding energy due to the lithiation of the Si electrode. After the subsequent delithiation process, the Si 2p peak from the lithium silicide partially shifts back to a higher binding energy. As a result, in situ XPS measurements of the lithiation/delithiation reactions are successfully performed using the developed system.
2021 Roadmap: electrocatalysts for green catalytic processes
Authors: Liu Jiandong , Ma Jianmin , Zhang Zhicheng , Qin Yuchen , Wang Yan-Jie , Wang Yao , Tan Rou , Duan Xiaochuan , Tian Tong Zhen , Zhang Cai Hong , Xie Wen Wen , Li Nian-Wu , Yu Le , Yang Chenhuai , Zhao Yanyan , Zia Hamna , Nosheen Farhat , Zheng Guangchao , Gupta Suraj , Wu Xianhong , Wang Zhiyu , Qiu Jieshan , Zhou Guangyao , Xu Lin , Liu Kang , Fu Junwei , Liu Min , Choi Sang-Il , Xie Junfeng , Peng Xinwen , Li Tingzhen , Lin Gaoxin , Wang Jiacheng , Han Jingrui , Liang Hongyan , Li Shuyu , Zhang Xiaotao , Zhu Yating , He Ting , Cui Xiaoya , Wang Haiqing , Wei Zengxi , Liu Quanhui , Fan Guangyin , Liu Qian , Sun Xuping , Feng Yuezhan , Liu Yaping , Chu Ke , Qiu Yuan , Liu Xijun
Published: December 2020

Serious challenges in energy and the environment require us to find solutions that use sustainable processes. There are many sustainable electrocatalytic processes that might provide the answers to the above-mentioned challenges, such as the oxygen reduction reaction (ORR), water splitting, the carbon dioxide reduction reaction (CO2RR), and the nitrogen reduction reaction (NRR). These reactions can enhance the value added by producing hydrogen energy through water splitting or convert useless CO2 and N2 into fuels and NH3. These electrocatalytic reactions can be driven by high-performance catalysts. Therefore, the exploration of novel electrocatalysts is one of the important electrocatalytic fields. In this paper, we aim to systematically discuss a variety of electrocatalysts used for sustainable processes and to give further insights into their status and associated challenges. We invited many famous research groups to write this roadmap with topics including platinum (Pt) and its alloys for ORR, oxides for ORR, chalcogenides for ORR, carbon-based hollow electrocatalysts for ORR, carbides for ORR, atomically dispersed Fe–N–C catalysts for ORR, metal-free catalysts for ORR, single-atom catalysts (SACs) for ORR, metal boride (MB) electrocatalysts for water splitting, transitional metal carbides (TMCs) for water splitting, transition metal (TM) phosphides for water splitting, oxides for water splitting, sulfides for water splitting, layered double hydroxides for water splitting, carbon-based electrocatalysts for water splitting, Ru-based electrocatalysts for water splitting, metal oxides for CO2RR, metal sulfides for CO2RR, metals for CO2RR, carbon for CO2RR, SACs for CO2RR, heterogeneous molecular catalysts for CO2RR, oxides for NRR, chalcogenides for NRR, C3N4 for NRR, SACs for NRR, etc. Their contributions enabled us to compile this 2020 roadmap on electrocatalysts for green catalytic processes and provide some suggestions for future researchers.
Deep learning in electron microscopy
Authors: Ede Jeffrey M
Published: December 2020

Deep learning is transforming most areas of science and technology, including electron microscopy. This review paper offers a practical perspective aimed at developers with limited familiarity. For context, we review popular applications of deep learning in electron microscopy. Following, we discuss hardware and software needed to get started with deep learning and interface with electron microscopes. We then review neural network components, popular architectures, and their optimization. Finally, we discuss future directions of deep learning in electron microscopy.
The transformer earthquake alerting model: a new versatile approach to earthquake early warning
Authors: Münchmeyer Jannes , Bindi Dino , Leser Ulf , Tilmann Frederik
Published: December 2020

Earthquakes are major hazards to humans, buildings and infrastructure. Early warning methods aim to provide advance note of incoming strong shaking to enable preventive action and mitigate seismic risk. Their usefulness depends on accuracy, the relation between true, missed and false alerts and timeliness, the time between a warning and the arrival of strong shaking. Current approaches suffer from apparent aleatoric uncertainties due to simplified modelling or short warning times. Here we propose a novel early warning method, the deep-learning based transformer earthquake alerting model (TEAM), to mitigate these limitations. TEAM analyses raw, strong motion waveforms of an arbitrary number of stations at arbitrary locations in real-time, making it easily adaptable to changing seismic networks and warning targets. We evaluate TEAM on two regions with high seismic hazard, Japan and Italy, that are complementary in their seismicity. On both data sets TEAM outperforms existing early warning methods considerably, offering accurate and timely warnings. Using domain adaptation, TEAM even provides reliable alerts for events larger than any in the training data, a property of highest importance as records from very large events are rare in many regions.
Brain cell type-specific endocytosis of arylsulfatase A identifies limitations of enzyme-based therapies for metachromatic leukodystrophy
Authors: Kaminski Debora , Yaghootfam Claudia , Matthes Frank , Reßing Annika , Gieselmann Volkmar , Matzner Ulrich
Published: December 2020

Enzyme replacement therapies, allogeneic bone marrow transplantation and gene therapies are treatment options for lysosomal storage diseases caused by inherited deficiencies of soluble lysosomal enzymes. Independent from the approach, the enzyme must be delivered to lysosomes of deficient patient cells. Little is known about the dissemination of enzyme within a tissue where cells compete for uptake via different receptor systems, binding affinities and endocytic rates. To evaluate dissemination and lysosomal targeting of a lysosomal enzyme in the CNS, we analysed receptor-mediated endocytosis of arylsulfatase A (ASA) by different types of brain-derived cell lines and primary murine brain cells. For ASA expressed by chinese hamster ovary cells for enzyme replacement therapy of metachromatic leukodystrophy, endocytic rates decline from microglia to neurons and astrocytes and to oligodendrocytes. Only immature oligodendrocytes endocytose significant amounts of enzyme. Uptake by non-microglial cells is due to mannose 6-phosphate receptors, whereas several receptor systems participate in endocytosis by microglial cells. Interestingly, ASA expressed by microglial cells cannot be taken up in a mannose 6-phosphate dependent manner. The resulting failure to correct non-microglial cells corroborates in vivo data and indicates that therapeutic effects of allogeneic bone marrow transplantation and hematopoietic stem cell gene therapy on metachromatic leukodystrophy are independent of metabolic cross-correction of neurons, astrocytes and oligodendrocytes by receptor-mediated endocytosis.
Worldwide burden of genital human papillomavirus infection in female sex workers: a systematic review and meta-analysis
Authors: Wu Jie , Ding Cheng , Liu Xiaoxiao , Zhou Yuqing , Tian Guo , Lan Lei , Chen Can , Yan Danying , Huang Chenyang , Fu Xiaofang , Li Lanjuan , Yang Shigui
Published: December 2020

Background

Although female sex workers (FSWs) have long been identified as a key human papillomavirus (HPV)-affected population, the burden and scope of their disproportionate risk for HPV infection have not been systematically estimated. We therefore aimed to estimate the prevalence of HPV and the distribution of HPV types in FSWs at the country, regional and global levels.

Methods

We searched the PubMed, Embase, SCOPUS, EBSCO, ProQuest, Cochrane Library and Web of Science databases for articles published between 1 January 1990 and 31 June 2019. Studies of genital HPV prevalence in FSWs, or with sufficient data (e.g. adequate number of HPV-positive cases and sample size) to compute prevalence rates in FSWs, were included in this systematic review. The meta-analysis was completed using the random effects model.

Results

We ultimately identified 107 studies in 45 countries or regions with sufficient data to calculate HPV prevalence in FSWs. The pooled global HPV prevalence among FSWs was 39.5% (95% CI 35.3, 43.9%), with notable variations by WHO region and country. Globally, the five most common HPV types in FSWs were HPV16 (9.0%), HPV 52 (8.3%), HPV89 (7.0%), HPV58 (6.2%), and HPV53 (5.3%).

Conclusions

Our findings suggest that FSWs are disproportionately affected by HPV, which is more pronounced in the Western Pacific and African regions, and are therefore in need of prevention, treatment and care services.
The Extremal Number of Tight Cycles
Authors: Sudakov Benny , Tomon István
Published: December 2020

A tight cycle in an $r$-uniform hypergraph $\mathcal{H}$ is a sequence of $\ell \geq r+1$ vertices $x_1,...,x_{\ell }$ such that all $r$-tuples $\{x_{i},x_{i+1},...,x_{i+r-1}\}$ (with subscripts modulo $\ell $) are edges of $\mathcal{H}$. An old problem of V. Sós, also posed independently by J. Verstraëte, asks for the maximum number of edges in an $r$-uniform hypergraph on $n$ vertices, which has no tight cycle. Although this is a very basic question, until recently, no good upper bounds were known for this problem for $r\geq 3$. Here we prove that the answer is at most $n^{r-1+o(1)}$. This is tight up to the $o(1)$ error term, and it was shown recently by B. Janzer that this error term is indeed needed. Our proof is based on finding robust expanders in the line-graph of $\mathcal{H}$ together with certain density increment type arguments.
Neisseria gonorrhoeaeSequence Typing for Antimicrobial Resistance (NG-STAR) clonal complexes are consistent with genomic phylogeny and provide simple nomenclature, rapid visualization and antimicrobial resistance (AMR) lineage predictions
Authors: Golparian Daniel , Sánchez-Busó Leonor , Cole Michelle , Unemo Magnus
Published: December 2020

Objectives

Surveillance of antimicrobial resistance (AMR) in Neisseria gonorrhoeae, supported by molecular typing, ideally through genome sequencing, is imperative. We defined N. gonorrhoeae Sequence Typing for Antimicrobial Resistance (NG-STAR) clonal complexes (CCs) and validated their usefulness in gonococcal AMR surveillance.

Methods

All NG-STAR alleles and STs available in the public database (https://ngstar.canada.ca/) were analysed using PHYLOViZ 2.0 to define CCs according to the closest founder ST with ≥5 identical alleles and founding ST with the highest number of links. The published 2013 European gonococcal dataset (n = 1054), the 2016 WHO reference strain panel (n = 14) and N. gonorrhoeae isolates with ceftriaxone resistance determinant penA-60.001 (n = 7) from several countries were used for validation.

Results

The majority of the isolates (n = 1063) were designated to 71 CCs. The most common CC was CC90 (n = 194), followed by CC63 (n = 166), CC139 (n = 73), CC158 (n = 73) and CC127 (n = 62). CC90 included isolates belonging to the internationally spread MDR clone N. gonorrhoeae Multi-Antigen Sequence Typing (NG-MAST) G1407 (predominantly MLST ST1901). The ceftriaxone-resistant isolates with penA-60.001 (n = 7) belonged to CC73 or STs linking between CC90 and CC73 (ST233 and ST1133). Phylogenomic analysis revealed that NG-STAR CCs more appropriately correlated to phylogenomic AMR clusters compared with MLST STs, NG-MAST STs, NG-MAST genogroups and NG-STAR STs.

Conclusions

NG-STAR CCs: are consistent with the gonococcal genome phylogeny; allow rapid visualizations with limited computational requirements; provide a simple, reproducible and portable nomenclature (for WGS and conventional Sanger sequencing data); and predict AMR lineages. Phenotypic AMR surveillance, supplemented with WGS, is imperative and NG-STAR CCs can effectively support this.
Rates of COVID-19–Related Outcomes in Cancer Compared With Noncancer Patients
Authors: Sun Lova , Surya Sanjna , Le Anh N , Desai Heena , Doucette Abigail , Gabriel Peter , Ritchie Marylyn D , Rader Daniel , Maillard Ivan , Bange Erin , Huang Alexander C , Vonderheide Robert H , DeMichele Angela , Verma Anurag , Mamtani Ronac , Maxwell Kara N
Published: December 2020

Cancer patients are a vulnerable population postulated to be at higher risk for severe coronavirus disease 2019 (COVID-19) infection. Increased COVID-19 morbidity and mortality in cancer patients may be attributable to age, comorbidities, smoking, health care exposure, and cancer treatments, and partially to the cancer itself. Most studies to date have focused on hospitalized patients with severe COVID-19, thereby limiting the generalizability and interpretability of the association between cancer and COVID-19 severity. We compared outcomes of SARS-CoV-2 infection in 323 patients enrolled in a population-based study before the pandemic (n = 67 cancer patients; n = 256 noncancer patients). After adjusting for demographics, smoking status, and comorbidities, a diagnosis of cancer was independently associated with higher odds of hospitalization (odds ratio = 2.16, 95% confidence interval = 1.12 to 4.18) and 30-day mortality (odds ratio = 5.67, 95% confidence interval = 1.49 to 21.59). These associations were primarily driven by patients with active cancer. These results emphasize the critical importance of preventing SARS-CoV-2 exposure and mitigating infection in cancer patients.
Identity Management and Role Branding in Security Affairs: Alliance Building in Argentine Foreign Policy
Authors: Thies Cameron G , Wehner Leslie E
Published: December 2020

This paper argues that states needing to engage in short-term strategic manipulation of their identity will often turn to branding strategies. Branding allows leaders the flexibility to adopt new roles or reimagine existing roles to fit with the current security environment. Drawing on insights from role theory, social identity, and branding, we develop a theoretical framework to understand how leaders innovate in roles. We apply this framework to two episodes of Argentine–US relations. The first case focuses on the Argentine role of active independent (1933–1945) despite US efforts to ascribe the faithful ally role. Only near the conclusion of the war did Perón transition to an ally partner role for strategic reasons and without much of a branding strategy. The second case is that of Argentina's adoption of the faithful ally role with the United States accompanied by a strong branding strategy under President Menem beginning in 1989. While innovation in the first case was possible without branding (though short-lived), the second case shows a more substantive transformation in Argentina's role set. Branding helps to carve out space in the role set for new roles that may compete with existing ones and ensure their successful adoption and enactment.
What COVID-19 Teaches Us About Implicit Bias in Pediatric Health Care
Authors: Mulchan Siddika S , Wakefield Emily O , Santos Melissa
Published: December 2020

Objectives

To highlight the role of implicit bias in contributing to existing health disparities among pediatric populations during the coronavirus disease 2019 (COVID-19) pandemic and recommend strategies to reduce its impact.

Methods

A topical review of the recent literature on implicit bias describing its potential impact in key areas of pediatric health care within the context of COVID-19 was conducted.

Results

Pediatric provider implicit bias has been found to be similar to the general population and can negatively influence clinical decision-making and outcomes for marginalized youth and families, particularly under stressful conditions such as the COVID-19 pandemic. Implicit bias can be mitigated through strategies proposed at the individual, institutional/organizational, educational, and scientific/research levels.

Conclusions

The additional strain on provider resources, staff, and supplies created by COVID-19 may exacerbate providers’ susceptibility to implicit bias and contribute to health disparities. Pediatric psychologists are encouraged to recognize implicit biases in themselves and colleagues and promote identified strategies to reduce the impact of implicit bias on perpetuating health disparities in marginalized youth and families.
Attention-gating for improved radio galaxy classification
Authors: Bowles Micah , Scaife Anna M M , Porter Fiona , Tang Hongming , Bastien David J
Published: December 2020

In this work, we introduce attention as a state-of-the-art mechanism for classification of radio galaxies, using convolutional neural networks. We present an attention-based model that performs on par with previous classifiers while using more than 50 per cent fewer parameters than the next smallest classic CNN application in this field. We demonstrate quantitatively how the selection of normalization and aggregation methods used in attention-gating can affect the output of individual models, and show that the resulting attention maps can be used to interpret the classification choices made by the model. We observe that the salient regions identified by the our model align well with the regions an expert human classifier would attend to make equivalent classifications. We show that while the selection of normalization and aggregation may only minimally affect the performance of individual models, it can significantly affect the interpretability of the respective attention maps and by selecting a model which aligns well with how astronomers classify radio sources by eye, a user can employ the model in a more effective manner.
X-ray variability of the HMXB Cen X−3: evidence for inhomogeneous accretion flows
Authors: Sanjurjo-Ferrín G , Torrejón J M , Postnov K , Oskinova L , Rodes-Roca J J , Bernabeu G
Published: December 2020

Cen X−3 is a compact high-mass X-ray binary likely powered by Roche lobe overflow. We present a phase-resolved X-ray spectral and timing analysis of two pointed XMM–Newton observations. The first one took place during a normal state of the source, when it has a luminosity LX ∼ 1036 erg s−1. This observation covered orbital phases ϕ = 0.00–0.37, i.e. the egress from the eclipse. The egress light curve is highly structured, showing distinctive intervals. We argue that different intervals correspond to the emergence of different emitting structures. The light-curve analysis enables us to estimate the size of such structures around the compact star, the most conspicuous of which has a size ∼0.3R*, of the order of the Roche lobe radius. During the egress, the equivalent width of Fe emission lines, from highly ionized species, decreases as the X-ray continuum grows. On the other hand, the equivalent width of the Fe K α line, from near-neutral Fe, strengthens. This line is likely formed due to the X-ray illumination of the accretion stream. The second observation was taken when the source was 10 times X-ray brighter and covered the orbital phases ϕ = 0.36–0.80. The X-ray light curve in the high state shows dips. These dips are not caused by absorption but can be due to instabilities in the accretion stream. The typical dip duration, of about 1000 s, is much longer than the time-scale attributed to the accretion of the clumpy stellar wind of the massive donor star, but is similar to the viscous time-scale at the inner radius of the accretion disc.
The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: N-body mock challenge for galaxy clustering measurements
Authors: Rossi Graziano , Choi Peter D , Moon Jeongin , Bautista Julian E , Gil-Marín Hector , Paviot Romain , Vargas-Magaña Mariana , de la Torre Sylvain , Fromenteau Sebastien , Ross Ashley J , Ávila Santiago , Burtin Etienne , Dawson Kyle S , Escoffier Stéphanie , Habib Salman , Heitmann Katrin , Hou Jiamin , Mueller Eva-Maria , Percival Will J , Smith Alex , Zhao Cheng , Zhao Gong-Bo
Published: December 2020

We develop a series of N-body data challenges, functional to the final analysis of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 (DR16) galaxy sample. The challenges are primarily based on high-fidelity catalogues constructed from the Outer Rim simulation – a large box size realization (3h−1Gpc) characterized by an unprecedented combination of volume and mass resolution, down to 1.85 × 109h−1M⊙. We generate synthetic galaxy mocks by populating Outer Rim haloes with a variety of halo occupation distribution (HOD) schemes of increasing complexity, spanning different redshift intervals. We then assess the performance of three complementary redshift space distortion (RSD) models in configuration and Fourier space, adopted for the analysis of the complete DR16 eBOSS sample of Luminous Red Galaxies (LRGs). We find all the methods mutually consistent, with comparable systematic errors on the Alcock–Paczynski parameters and the growth of structure, and robust to different HOD prescriptions – thus validating the robustness of the models and the pipelines used for the baryon acoustic oscillation (BAO) and full shape clustering analysis. In particular, all the techniques are able to recover α∥ and α⊥ to within $0.9{{\ \rm per\ cent}}$, and fσ8 to within $1.5{{\ \rm per\ cent}}$. As a by-product of our work, we are also able to gain interesting insights on the galaxy–halo connection. Our study is relevant for the final eBOSS DR16 ‘consensus cosmology’, as the systematic error budget is informed by testing the results of analyses against these high-resolution mocks. In addition, it is also useful for future large-volume surveys, since similar mock-making techniques and systematic corrections can be readily extended to model for instance the Dark Energy Spectroscopic Instrument (DESI) galaxy sample.
Joint inference on the redshift distribution of fast radio burst and on the intergalactic baryon content
Authors: Hackstein S , Brüggen M , Vazza F
Published: December 2020

Context: Fast radio bursts are transient radio pulses of extragalactic origin. Their dispersion measure is indicative of the baryon content in the ionized intergalactic medium between the source and the observer. However, inference using unlocalized fast radio bursts is degenerate to the distribution of redshifts of host galaxies. Method: We perform a joint inference of the intergalactic baryon content and the fast radio burst redshift distribution with the use of Bayesian statistics by comparing the likelihood of different models to reproduce the observed statistics in order to infer the most likely models. In addition to two models of the intergalactic medium, we consider contributions from the local environment of the source, assumed to be a magnetar, as well as a representative ensemble of host and intervening galaxies. Results: Assuming that the missing baryons reside in the ionized intergalactic medium, our results suggest that the redshift distribution of observed fast radio bursts peaks at z ≲ 0.6. However, conclusions from different instruments regarding the intergalactic baryon content diverge and thus require additional changes to the observed distribution of host redshifts, beyond those caused by telescope selection effects.
Photometric analysis of three totally eclipsing W UMa stars with increasing periods: TYC 3700-1384-1, V1511 Her, and V1179 Her
Authors: Broens Eric
Published: December 2020

The first multicolour light-curve models and period studies for the totally eclipsing W UMa stars TYC 3700-1384-1, V1511 Her, and V1179 Her are presented. All three stars are A-subtype W UMa stars of spectral type F. The light-curve solutions show that TYC 3700-1384-1 has a moderately low mass ratio of q = 0.182 ± 0.001 and a degree of overcontact of $f = 49 {{\ \rm per\ cent}}$. For V1179 Her a mass ratio q = 0.153 ± 0.001 and a degree of overcontact of $f = 48 {{\ \rm per\ cent}}$ is derived. The solution for V1511 Her is inconclusive, however the mass ratio is expected to be between 0.13 < q < 0.15. The evolutionary status is compared with zero-age main sequence stars taking into account energy transfer from the primary to the secondary component. The primary component of TYC 3700-1384-1 fits well in the main-sequence, while V1179 Her is more evolved. The period study reveals for all three stars a continuously increasing period at a rate of ${{\mathrm{d}}P/{\mathrm{d}}t} = 6.1\times 10^{-7}\, \mathrm{d\, yr}^{-1}$, ${{\mathrm{d}}P/{\mathrm{d}}t} = 5.0\times 10^{-7}\, \mathrm{d\, yr}^{-1}$, and ${{\mathrm{d}}P/{\mathrm{d}}t} = 9.6\times 10^{-7}\, \mathrm{d\, yr}^{-1}$ for TYC 3700-1384-1, V1511 Her, and V1179 Her, respectively. The estimated mass transfer rates derived from these period changes are $\dot{M}=1.6 \times 10^{-7} {\, {\rm M}_\odot } \, \mathrm{yr}^{-1}$ for TYC 3700-1384-1 and $\dot{M}= 1.9 \times 10^{-7} {\, {\rm M}_\odot } \, \mathrm{yr}^{-1}$ for V1179 Her.
The atlas of RNase H antisense oligonucleotide distribution and activity in the CNS of rodents and non-human primates following central administration
Authors: Jafar-nejad Paymaan , Powers Berit , Soriano Armand , Zhao Hien , Norris Daniel A , Matson John , DeBrosse-Serra Beatrice , Watson Jamie , Narayanan Padmakumar , Chun Seung J , Mazur Curt , Kordasiewicz Holly , Swayze Eric E , Rigo Frank
Published: December 2020

Antisense oligonucleotides (ASOs) have emerged as a new class of drugs to treat a wide range of diseases, including neurological indications. Spinraza, an ASO that modulates splicing of SMN2 RNA, has shown profound disease modifying effects in Spinal Muscular Atrophy (SMA) patients, energizing efforts to develop ASOs for other neurological diseases. While SMA specifically affects spinal motor neurons, other neurological diseases affect different central nervous system (CNS) regions, neuronal and non-neuronal cells. Therefore, it is important to characterize ASO distribution and activity in all major CNS structures and cell types to have a better understanding of which neurological diseases are amenable to ASO therapy. Here we present for the first time the atlas of ASO distribution and activity in the CNS of mice, rats, and non-human primates (NHP), species commonly used in preclinical therapeutic development. Following central administration of an ASO to rodents, we observe widespread distribution and target RNA reduction throughout the CNS in neurons, oligodendrocytes, astrocytes and microglia. This is also the case in NHP, despite a larger CNS volume and more complex neuroarchitecture. Our results demonstrate that ASO drugs are well suited for treating a wide range of neurological diseases for which no effective treatments are available.
Network controllability-based algorithm to target personalized driver genes for discovering combinatorial drugs of individual patients
Authors: Guo Wei-Feng , Zhang Shao-Wu , Feng Yue-Hua , Liang Jing , Zeng Tao , Chen Luonan
Published: December 2020

Multiple driver genes in individual patient samples may cause resistance to individual drugs in precision medicine. However, current computational methods have not studied how to fill the gap between personalized driver gene identification and combinatorial drug discovery for individual patients. Here, we developed a novel structural network controllability-based personalized driver genes and combinatorial drug identification algorithm (CPGD), aiming to identify combinatorial drugs for an individual patient by targeting personalized driver genes from network controllability perspective. On two benchmark disease datasets (i.e. breast cancer and lung cancer datasets), performance of CPGD is superior to that of other state-of-the-art driver gene-focus methods in terms of discovery rate among prior-known clinical efficacious combinatorial drugs. Especially on breast cancer dataset, CPGD evaluated synergistic effect of pairwise drug combinations by measuring synergistic effect of their corresponding personalized driver gene modules, which are affected by a given targeting personalized driver gene set of drugs. The results showed that CPGD performs better than existing synergistic combinatorial strategies in identifying clinical efficacious paired combinatorial drugs. Furthermore, CPGD enhanced cancer subtyping by computationally providing personalized side effect signatures for individual patients. In addition, CPGD identified 90 drug combinations candidates from SARS-COV2 dataset as potential drug repurposing candidates for recently spreading COVID-19.
Ecd promotes U5 snRNP maturation and Prp8 stability
Authors: Erkelenz Steffen , Stanković Dimitrije , Mundorf Juliane , Bresser Tina , Claudius Ann-Katrin , Boehm Volker , Gehring Niels H , Uhlirova Mirka
Published: December 2020

Pre-mRNA splicing catalyzed by the spliceosome represents a critical step in the regulation of gene expression contributing to transcriptome and proteome diversity. The spliceosome consists of five small nuclear ribonucleoprotein particles (snRNPs), the biogenesis of which remains only partially understood. Here we define the evolutionarily conserved protein Ecdysoneless (Ecd) as a critical regulator of U5 snRNP assembly and Prp8 stability. Combining Drosophila genetics with proteomic approaches, we demonstrate the Ecd requirement for the maintenance of adult healthspan and lifespan and identify the Sm ring protein SmD3 as a novel interaction partner of Ecd. We show that the predominant task of Ecd is to deliver Prp8 to the emerging U5 snRNPs in the cytoplasm. Ecd deficiency, on the other hand, leads to reduced Prp8 protein levels and compromised U5 snRNP biogenesis, causing loss of splicing fidelity and transcriptome integrity. Based on our findings, we propose that Ecd chaperones Prp8 to the forming U5 snRNP allowing completion of the cytoplasmic part of the U5 snRNP biogenesis pathway necessary to meet the cellular demand for functional spliceosomes.
Vitamin D Deficiency or Supplementation and the Risk of Human Herpesvirus Infections or Reactivation: A Systematic Review and Meta-analysis
Authors: Lin Liang-Yu , Bhate Ketaki , Forbes Harriet , Smeeth Liam , Warren-Gash Charlotte , Langan Sinéad M
Published: December 2020

Background

Vitamin D may protect against respiratory virus infections, but any association with herpesviruses is unclear.

Methods

We undertook a systematic review of vitamin D deficiency or supplementation and the risk of 8 human herpesviruses. Six databases and 4 gray literature databases were searched for relevant cohort studies, case–control studies, and clinical trials.

Results

Ten studies were included, all conducted among immunosuppressed patients. There was no evidence that vitamin D deficiency is associated with cytomegalovirus (CMV) disease (pooled risk ratio, 1.06; 95% CI, 0.66–1.7), herpes zoster after transplantation (1 study), or HHV-8 among HIV patients (1 study). Vitamin D supplementation may decrease herpes zoster among hemodialysis patients (1 study) or CMV disease after renal transplantation (1 study), but supplementation was not associated with reduced EBV viral load among multiple sclerosis patients (1 study).

Conclusions

Any association between vitamin D and herpesviruses remains inconclusive. Further studies in the general population are needed.
Why is COVID-19 more deadly to nursing home residents?
Authors: Su Z , McDonnell D , Li Y
Published: December 2020

COVID-19 is deadly to older adults, with research showing that being older and having underlying chronic diseases are significant risk factors for COVID-19 related deaths. However, though similarities exist between both nursing home residents and older community-dwelling people, nursing home residents are substantially more vulnerable to COVID-19. A closer review of both demographic groups provides clarity concerning the difference within the context of COVID-19. Therefore, to address the research gap, drawing insights from Maslow’s hierarchy of needs model, this article aims to examine similarities and differences in COVID-19 risk factors experienced by nursing home residents and community-dwelling older people.
Complement promotes endothelial von Willebrand factor and angiopoietin-2 release in obstructive sleep apnea
Authors: Gao Su , Emin Memet , Thoma Theodosia , Pastellas Kalliopi , Castagna Francesco , Shah Riddhi , Jimenez Alondra , Patel Neha , Wei Ying , Jelic Sanja
Published: December 2020

Study Objective

Obstructive sleep apnea (OSA) is highly prevalent and triples vascular thromboembolic risk. Intermittent hypoxia (IH) during transient cessation of breathing in OSA impairs endothelial protection against complement. Complement activation stimulates the endothelial release of a pro-thrombotic von Willebrand factor (vWF). We investigated whether increased complement activity in OSA promotes the endothelial release of vWF and pro-inflammatory angiopoietin-2. We further investigated whether improving complement protection with statins reverses these changes.

Methods

Using endothelial cells (ECs) and blood collected from OSA patients (n = 109) and controls (n = 67), we assessed whether altered cellular localization of complement inhibitor CD59 in OSA modulates exocytosis of Weibel-Palade bodies (WPB), secretory granules that store vWF and angiopoietin-2. These interactions were also assessed in vitro in ECs exposed to normoxia or IH with or without recombinant complement C9 and with or without atorvastatin.

Results

Circulating levels of angiopoietin-2 were greater in OSA than controls and levels of vWF cleavage products correlated with OSA severity. In cultured ECs, IH enhanced complement-stimulated angiopoietin-2 and vWF release by reducing EC surface and increasing intracellular expression of complement inhibitor CD59. Intracellular CD59 co-localized with WPB in OSA. IH increased binding of intracellular CD59 to syntaxin-3, which dissociated syntaxin-3 from voltage-sensitive calcium channel Cav1.2, and activated WPB exocytosis in a calcium-dependent manner. Atorvastatin reversed IH-enhanced endothelial release of vWF and angiopoietin-2.

Conclusions

IH promotes the complement-mediated release of vWF and angiopoietin-2, which may contribute to pro-thrombotic and pro-inflammatory conditions in OSA. Statin reversed these effects, suggesting a potential approach to reduce cardiovascular risk in OSA.
Hypochlorous acid decreases antioxidant power, inhibits plasma membrane redox system and pathways of glucose metabolism in human red blood cells
Authors: Qadir Tantry Irfan , Ali Asif , Mahmood Riaz
Published: December 2020

Hypochlorous acid (HOCl) is generated at a high concentration by activated neutrophils at sites of inflammation in a myeloperoxidase catalyzed reaction. The increased and sustained production of HOCl at inflammatory sites may lead to tissue injury and this process is believed to play an important role in the progression of several diseases like chronic inflammation, atherosclerosis and some types of cancers. We have examined the effect of HOCl on human red blood cells (RBCs) under in vitro conditions. Treatment of RBC with different concentrations of HOCl (0.05–2.5 mM) at 37°C resulted in decreased activities of major antioxidant enzymes while the antioxidant power of RBC was weakened, as shown by lowered metal-reducing and free radical quenching ability of HOCl treated cells. RBC plasma membrane redox system was also inhibited suggesting membrane damage. The enzymes of glucose metabolism were inhibited indicating deranged energy metabolism. Electron microscopic images showed gross morphological changes in HOCl treated RBC. These results show that HOCl causes major alterations in the cellular antioxidant defense system and inhibition of glycolytic pathways, which increase the susceptibility of RBC to oxidative damage.
Value of C-reactive protein in differentiating viral from bacterial aetiologies in patients with non-malaria acute undifferentiated fever in tropical areas: a meta-analysis and individual patient data study
Authors: Otten Twan , de Mast Quirijn , Koeneman Bouke , Althaus Thomas , Lubell Yoel , van der Ven André
Published: December 2020

C-reactive protein (CRP) is used to discriminate common bacterial and viral infections, but its utility in tropical settings remains unknown. We performed a meta-analysis of studies performed in Asia and Africa. First, mean CRP levels for specific tropical infections were calculated. Thereafter, individual patient data (IPD) from patients with non-malarial undifferentiated fever (NMUF) who were tested for viral and bacterial pathogens were analysed, calculating separate cut-off values and their performance in classifying viral or bacterial disease. Mean CRP levels of 7307 patients from 13 countries were dengue 12.0 mg/l (standard error [SE] 2.7), chikungunya 41.0 mg/l (SE 19.5), influenza 15.9 mg/l (SE 6.3), Crimean–Congo haemorrhagic fever 9.7 mg/l (SE 4.7), Salmonella 61.9 mg/l (SE 5.4), Rickettsia 61.3 mg/l (SE 8.8), Coxiella burnetii 98.7 mg/l (SE 44.0) and Leptospira infections 113.8 mg/l (SE 23.1). IPD analysis of 1059 NMUF patients ≥5 y of age showed CRP <10 mg/l had 52% sensitivity (95% confidence interval [CI] 48 to 56) and 95% specificity (95% CI 93 to 97) to detect viral infections. CRP >40 mg/l had 74% sensitivity (95% CI 70 to 77) and 84% specificity (95% CI 81 to 87) to identify bacterial infections. Compared with routine care, the relative risk for incorrect classification was 0.64 (95% CI 0.55 to 0.75) and the number needed to test for one extra correctly classified case was 8 (95% CI 6 to 12). A two cut-off value CRP test may help clinicians to discriminate viral and bacterial aetiologies of NMUF in tropical areas.
Basic sanitation: a new indicator for the spread of COVID-19?
Authors: Silva Renata R , Ribeiro Caique J N , Moura Tatiana R , Santos Márcio B , Santos Allan D , Tavares Débora S , Santos Priscila L
Published: December 2020

Background

Basic sanitation could be a potential indicator of the spread of coronavirus disease-2019 (COVID-19) and, in this context, space-time patterns are important tools with which to elucidate the spread of disease and identify risk factors. The aim of this study was to assess a possible association between basic sanitation indices and COVID-19 rates in all the 5570 municipalities of Brazil and its spatial distribution.

Methods

Data of COVID-19 cases registered in Brazil from 28 February until 31 May 2020 and independent variables associated with basic sanitation were included.

Results

High incidence rates were significantly associated with precarious water service index (0–25% coverage) and offstandard faecal coliforms index for tap water (5–50% and 75–100% of samples tested). A significant association between high mortality rates and sewage collection (0–25% coverage)/treatment (25–50% coverage) indices was also verified. In addition, clusters with significant spatial autocorrelation were identified mainly in the North and Northeast regions for mortality and incidence rates (high-high risk areas) and for offstandard faecal coliforms index. Those regions are considered the poorest in Brazil, presenting with low incomes, human agglomerations, as well as a poor basic sanitation system, which also hinder the implementation of COVID-19-preventative measures.

Conclusions

A precarious basic sanitation infrastructure could potentially be associated with the high transmission of severe acute respiratory syndrome coronavirus-2 in Brazil.
Direct Oral Anticoagulants Versus Vitamin-K Antagonist After PCIs in Patients With AF: A Meta-analysis of Cardiac Ischemic Events
Authors: Cordero Alberto , Ferreiro José L. , Bertomeu-González Vicente , Rodríguez-Mañero Moisés , Fácila Lorenzo , Escribano David , Sanchez-Recalde Angel , Zuazola Pilar , Ruiz-Nodar Juan M. , González-Juanatey Jose R.
Published: December 2020

Background:

Clinical trials have assessed the effect of direct oral antagonists (DOACs) in patients with atrial fibrillation (AF) after percutaneous coronary interventions (PCI). Studies were designed to test the effect on bleeding incidence, but concerns related to safety on ischemic events remain.

Methods:

We performed a meta-analysis with currently available studies involving DOACs versus Vitamin-K antagonist (VKA) in patients with AF after PCI. The primary endpoint was the incidence of cardiac ischemic events, including myocardial infarction and stent thrombosis. Secondary endpoints were the incidence of stroke, all-cause mortality, and major bleeding.

Results:

Eleven thousand twenty-three patients were included in the analysis: 5510 receiving DOACs and 5513 VKA. A total of 190 cases of myocardial infarction were registered in patients treated with DOACs and 177 in patients on VKA, and no statistical difference was noted [relative risk (RR): 1.07 95% confidence interval (CI) 0.88–1.31]. The incidence of stent thrombosis was very low with no differences between both treatment strategies (RR: 1.14 95% CI 0.76–1.71). The incidence of cardiac ischemic events was the same in patients receiving DOACs or VKA (HR 1.09 95% CI 0.91–1.30). No differences were observed in the incidence of stroke (RR: 0.86 95% CI 0.61–1.23) or mortality (RR: 1.09, 95% CI 0.90–1.31). Treatment with DOACs was associated with 34% reduction in major bleeding (RR: 0.66, 95% CI 0.54–0.81).

Conclusions:

Treatment with DOACs in patients with AF after a PCI do not increase the risk of cardiac ischemic events, stroke, or death and reduce the incidence of major bleeding by 34% as compared with VKA.