bluuebunny/crossref_metadata_2025 huggingface dataset:
High-grade atrioventricular block occurring during percutaneous closure of patent foramen ovale: a case report
Authors: Kibler Marion , Marzak Halim , Jesel Laurence , Ohlmann Patrick
Published: June 2020

Background 

Percutaneous closure of patent foramen ovale (PFO) is recommended for patients presenting with PFO-related stroke. Acute high-grade conduction disturbances occurring during PFO closure procedure have not been previously reported.

Case summary 

We describe for the first time a case of reversible complete atrioventricular block which occurred during closure of a PFO.

Discussion 

We hypothesized that the block was the result of atrioventricular node compression—likely caused by the right-atrial disc of the 35-mm PFO closure device. We suggest implanting smaller devices in order to prevent atrioventricular conduction disturbances.
A novel pathway: chest wall percutaneous closure for an aortic pseudoaneurysm
Authors: Hu Min , Fang Zemin , Bo Zhixiang , Wei Xiang
Published: June 2020

Ascending aortic pseudoaneurysm is difficult to treat with traditional surgical techniques. We report a case involving a 32-year-old man with ascending aortic pseudoaneurysm who underwent a series of prior operations, including the Bentall procedure with total aortic arch replacement for type A aortic dissection and postoperative sternal resection for chronic osteomyelitis of the sternum. He was successfully treated with percutaneous device closure of the pseudoaneurysm with an atrial septal defect occluder. This case illustrates successful closure of ascending aortic pseudoaneurysm via a chest wall percutaneous approach.
Dynamics of bacterioplankton community structure in response to seasonal hydrological disturbances in Poyang Lake, the largest wetland in China
Authors: Zhao Man , Ma Yan-tian , He Shi-yao , Mou Xiaozhen , Wu Lan
Published: June 2020

Bacterioplankton communities play a critical role in biogeochemical cycling in freshwater environments, but how the hydrological regime impacts the assembly of bacterioplankton communities remains unclear. This study examined differences in bacterioplankton community structures between wet (July and September) and dry (October and November) seasons in two consecutive years (2016 and 2017) in Poyang Lake, the largest seasonal freshwater lake in China. Our results revealed no overall difference in bacterioplankton compositions and their predicted functions among spatially separated sites. However, bacterioplankton communities did show significant temporal shifts, mainly between samples in November and other months. Transitions from the dry to the wet season were observed in October in both sampling years. Meanwhile, insignificant spatial but significant temporal differences were also found for physicochemical variables. Moreover, redundancy analysis indicates that compared with water depth, water temperature was found to better explain changes in the bacterioplankton community. These findings consistently indicate that the bacterioplankton community in Poyang Lake is relatively less sensitive to annual hydrology shifts than water temperature and nutrient conditions.
NAD(P)H-dependent thioredoxin-disulfide reductase TrxR is essential for tellurite and selenite reduction and resistance in Bacillus sp. Y3
Authors: Yasir Muhammad , Zhang Yuxiao , Xu Zixiao , Luo Meizhong , Wang Gejiao
Published: June 2020

Microbial reduction of selenite [Se(IV)] and tellurite [Te(IV)] to Se(0) and Te(0) can function as a detoxification mechanism and serve in energy conservation. In this study, Bacillus sp. Y3 was isolated and demonstrated to have an ability of simultaneous reduction of Se(IV) and Te(IV) during aerobic cultivation, with reduction efficiencies of 100% and 90%, respectively. Proteomics analysis revealed that the putative thioredoxin disulfide reductase (TrxR) and sulfate and energy metabolic pathway proteins were significantly upregulated after the addition of Se(IV) and Te(IV). qRT-PCR also showed an increased trxR transcription level in the presence of Se(IV) and Te(IV). Compared with a wild-type Escherichia coli strain, the TrxR-overexpressed E. coli strain showed higher Se(IV) and Te(IV) resistance levels and reduction efficiencies. Additionally, the TrxR showed in vitro Se(IV) and Te(IV) reduction activities when NADPH or NADH were present. When NADPH was used as the electron donor, the optimum conditions for enzyme activities were pH 8.0 and 37°C. The Km values of Te(IV) and Se(IV) were 16.31 and 2.91 mM, and the Vmax values of Te(IV) and Se(IV) were 12.23 and 11.20 µM min−1 mg−1, respectively. The discovery of the new reductive enzyme TrxR enriches the repertoire of the bacterial Se(IV) and Te(IV) resistance and reduction mechanisms. Bacillus sp. Y3 can efficiently reduce Se(IV) and Te(IV) simultaneously. Strain Y3 provides potential applications for selenite and tellurite bioremediation. The TrxR enzyme shows high catalytic activity for reducing Se(IV) and Te(IV). The discovery of TrxR enriches the bacterial Se(IV) and Te(IV) reduction mechanisms.
The HlyD-like membrane fusion protein All5304 is essential for acid stress survival of the filamentous cyanobacterium Anabaena sp. PCC 7120
Authors: Shvarev Dmitry , Maldener Iris
Published: June 2020

Acid stress is an environmental problem for plants and fresh water cyanobacteria like the filamentous, heterocyst forming species Anabaena sp. PCC 7120 (hereafter Anabaena sp.). Heterocyst differentiation, cell–cell communication and nitrogen fixation has been deeply studied in this model organism, but little is known about the cellular response of Anabaena sp. to decreased pH values, causing acid stress. ATP-binding cassette (ABC) transporters are involved in acid stress response in other bacteria, by exporting proteins responsible for survival under acidification. The genome of Anabaena sp. encodes numerous ABC transporter components, whose function is not known yet. Here, we describe the function of the gene all5304 encoding a protein with homology to membrane fusion proteins of tripartite efflux pumps driven by ABC transporters like HlyBD-TolC of Escherichia coli. The all5304 mutant shows less resistance against low pH, even though the expression of the gene is independent from the pH of the medium. We compared the exoproteome of the wild type and mutant cultures and identified three proteins-candidate substrates of the putative transporter. Including the in silico analysis of All5304, our results suggest that All5304 functions as part of an efflux pump, secreting of a protein necessary for acid tolerance in Anabaena sp.
Optimization of scotta as growth medium to preserve biodiversity and maximise bacterial cells concentration of natural starter cultures for Pecorino Romano PDO cheese
Authors: Chessa Luigi , Paba Antonio , Daga Elisabetta , Caredda Marco , Comunian Roberta
Published: June 2020

Preservation of cheese microbiota biodiversity is central to the sensory quality of traditional and PDO cheeses. Lyophilized commercial selected starters, being advantageous in terms of cells concentration, are supplanting natural cultures causing important loss of microbial biodiversity in the dairy environment. Biodiversity could be recovered using natural starter cultures, however their cells concentration after propagation is lower than the commercial ones. Two autochthonous and biodiverse starter cultures (MixA and MixB) coming from scotta (residual whey from Ricotta cheese manufacture), collected in the 1960 s from Pecorino Romano PDO cheese manufactures, were revitalized in reconstituted commercial powder scotta. The aim of this study was the propagation of the microbial starter mixes increasing their bacterial concentration in the pellet, reducing nonessential scotta components by a fast and not-expensive method, without changing the microbial community balance. The behaviour of each mix inoculated in scotta was compared to that in half-concentrated, clarified, and half-concentrated-clarified scotta. Higher cells concentration in the pellets from the modified scotta was obtained, without changing technological performances and microbial fingerprint. The pellets obtained were reinoculated in commercial scotta for the preparation of the scotta-innesto (the typical starter for Pecorino Romano), and no differences were observed among the treatments after incubation. The reduction of nonessential scotta's components could help the reproduction of natural starter cultures preserving their properties.
Peripheral IL-6 Levels but not Sarcopenia Are Predictive of 1-Year Mortality After Hip Fracture in Older Patients
Authors: Bermejo-Bescós Paloma , Martín-Aragón Sagrario , Cruz-Jentoft Alfonso José , Merello de Miguel Ana , Vaquero-Pinto María-Nieves , Sánchez-Castellano Carmen
Published: June 2020

Background

Sarcopenic patients may have an increased risk of poor outcomes after a hip fracture. The objective of this study was to determine whether sarcopenia and a set of biomarkers were potential predictors of 1-year-mortality in older patients after a hip fracture.

Methods

About 150 patients at least 80 years old were hospitalized for the surgical treatment of a hip fracture. The primary outcome measure was the death in the first year after the hip fracture. Sarcopenia was defined at baseline by having both low muscle mass (bioimpedance analysis) and handgrip and using the updated European Working Group on Sarcopenia in Older People (EWGSOP2) definition of probable sarcopenia. Janssen’s (J) and Masanés (M) cutoff points were used to define low muscle mass.

Results

Mortality 1 year after the hip fracture was 11.5%. In univariate analyses, baseline sarcopenia was not associated with mortality, using neither of the muscle mass cutoff points: 5.9% in sarcopenic (J) versus 12.4% in non-sarcopenic participants (p = .694) and 16% in sarcopenic (M) versus 9.6% in non-sarcopenic participants (p = .285). Probable sarcopenia (EWGSOP2) was not associated with mortality. Peripheral levels of IL-6 at baseline were significantly higher in the group of participants who died in the year after the hip fracture (17.14 ± 16.74 vs 11.42 ± 7.99 pg/mL, p = .026). TNF-α peripheral levels had a nonsignificant trend to be higher in participants who died. No other biomarker was associated with mortality.

Conclusions

Sarcopenia at baseline was not a predictor of 1-year mortality in older patients after a hip fracture. IL-6 was associated with a higher risk of mortality in these patients, regardless of sarcopenia status.
Pathways to Educational Disparities in Disability Incidence: The Contributions of Excess Body Mass Index, Smoking, and Manual Labor Involvement
Authors: Townsend Tarlise , Mehta Neil K
Published: June 2020

Objectives

In the United States, educational disparities in disability are large and increasing, but the mechanisms underlying them are not well understood. We estimate the proportion of population-level educational disparities in disability incidence explained by excess body mass index (BMI), smoking, and manual labor.

Method

We use waves 2003–2015 of the nationally representative Panel Study of Income Dynamics to calculate observed disability incidence and counterfactual incidence absent the key mediators (3,129 individuals; 13,168 observations). We take advantage of earlier-life measures, including childhood socioeconomic status, 1986 BMI, and occupational history between 1968 and 2001. To account for distinct processes in women and men at middle versus older ages, we stratify by gender and at age 65.

Results

Educational disparities in disability incidence were evident in women and men at younger and older ages, and were largest among older women. Together, the mediators of interest were estimated to explain roughly 60% of disparities in younger women, 65%–70% in younger men, 40% in older women, and 20%–60% in older men. The main contributors to disparities appeared to be excess BMI and smoking in younger women; manual labor and smoking in younger men; excess BMI in older women; and smoking in older men.

Discussion

These mediators explain much of disparities in earlier-age disability; successful interventions to address these factors may substantially reduce them. However, a considerable proportion of disparities remained unexplained, particularly at older ages, reflecting the myriad pathways by which educational attainment can influence disability status.
Creative Dislocation: an Experiment in Collaborative Historical Research
Authors: Bickers Robert , Cole Tim , Dudley Marianna , Hanna Erika , McLellan Josie , Pooley William , Williamson Beth
Published: June 2020

This article introduces an experiment in collaborative historical practice. It describes how six historians visited the East Devon village of Branscombe, with the aim of creatively engaging with the present and past of the village. This was a collaborative and collective act of what we term here ‘creative dislocation’. By dislocating from our usual routines, subjects, places, methods, and styles, and adopting creative methods and constraints, we aimed to shed light on the role of creativity in the historical research process. Our experiment resulted in six pieces of writing – three of which are presented here. However, a key argument of this article is that creativity lies in process as much as in the finished product. Creative work happened at each stage of the research process, in ways that were not always immediately visible in the final written pieces. The creativity in historical research and writing does not necessarily lie in opposition to archival explorations and fact-driven narratives, but can also lie within them. Creativity informs the questions we ask, our ways of working with the archive and our approach to writing.
Rheological characteristics of polyethylene-nanotube composites by capillary rheometry
Authors: Al-Baghdadi S , Al-Amiery A
Published: June 2020

The viscosity and flow rate as rheological characteristics are fundamental in evaluating the nanofillers in processing the polyethylene-nanotube (PE-NT) composite in injecting molding. The purpose of this investigation is to study the rheological conduct of PE-NT composite plastic feedstock through capillary rheometry. For the purpose of obtaining a flawless component, the feedstock is used as a critical parameter, and care must be taken while introducing the raw materials with high solid load and hence perfect flowability. The shear rate viscosity of different feedstocks at an NT ratio extending at 0–3 wt.% has been determined at L/D equal to 10 die and a load extending at 40.0–80.0 KGF at temperatures 140.0, 150.0 and 160.0°C. The three specimens’ viscosity was measured in order to exhibit that the corresponding flow conduct factor varies from 0.40 to 0.70, demonstrating the non-Newtonian behavior of the specimens. The three specimens’ activation energies at the studied temperature degrees were evaluated and turned out to be 36.5–69.88 kJ/mol according to the applied load.
Sensitivity and Specificity of Rapid Diagnostic Tests for Hepatitis C Virus With or Without HIV Coinfection: A Multicentre Laboratory Evaluation Study
Authors: Vetter Beatrice N , Reipold Elena Ivanova , Ongarello Stefano , Audu Rosemary , Ige Fehintola A , Alkhazashvili Maia , Chitadze Nazibrola , Vanroye Fien , De Weggheleire Anja , An Sokkab , Fransen Katrien
Published: June 2020

Background

Hepatitis C virus (HCV) screening is critical to HCV elimination efforts. Simplified diagnostics are required for low-resource settings and difficult-to-reach populations. This retrospective study assessed performance of rapid diagnostic tests (RDTs) for detection of HCV antibodies.

Methods

Two lots of 13 RDTs were evaluated at 3 laboratories using archived plasma samples from 4 countries (Nigeria, Georgia, Cambodia, and Belgium). HCV status was determined using 3 reference tests according to a composite algorithm. Sensitivity and specificity were evaluated in HIV-infected and HIV-uninfected populations. Operational characteristics were also assessed.

Results

In total, 1710 samples met inclusion criteria. In HIV-uninfected samples (n = 384), the majority of RDTs had sensitivity ≥98% in 1 or both lots and most RDTs had specificity ≥99%. In HIV-infected samples (n = 264), specificity remained high but sensitivity was markedly lower than in HIV-uninfected samples; only 1 RDT reached >95%. The majority of HIV-infected samples for which sensitivity was low did not have detectable HCV viral load/core antigen. Interreader variability, lot-to-lot variability, and rate of invalid runs were low for all RDTs (<2%).

Conclusions

HCV RDTs should be evaluated in the intended target population, as sensitivity can be impacted by population factors such as HIV status.

Clinical Trials Registration

NCT04033887
A novel community-acquired MRSA clone, USA300-LV/J, uniquely evolved in Japan
Authors: Takadama Shunsuke , Nakaminami Hidemasa , Kaneko Hiroshi , Noguchi Norihisa
Published: June 2020

Background

USA300 [ST8-staphylococcal cassette chromosome mec type IVa (ST8-IVa)/arginine catabolic mobile element (ACME) positive] is a major Panton–Valentine leucocidin (PVL)-positive community-acquired MRSA (CA-MRSA) clone. In Japan, we identified USA300-like strains with characteristics (ST8-IVc/ACME negative) similar to those of USA300.

Objectives

To reveal the evolution of the USA300-like strains.

Methods

The whole-genome sequence of a USA300-like strain was determined and genome analysis was performed using Type Strain Genome Server, MUSCLE and progressiveMauve.

Results

Genome-based phylogenetic analysis showed that the USA300-like strain is more similar to the USA300-Latin American variant (USA300-LV), which is a PVL-positive CA-MRSA clone identified in South America, than to USA300. Instead of the ACME, copper and mercury resistance mobile elements were located on the genome of the USA300-like strain. In addition, the USA300-like strain possessed a unique mobile genetic element, ICE6013. Therefore, we named this novel USA300-LV variant identified in Japan as USA300-LV/J.

Conclusions

Our findings strongly suggest that a PVL-positive CA-MRSA USA300-LV/J clone originating from abroad has uniquely evolved and disseminated in Japan.
Nationwide surveillance of azole-resistant Aspergillus fumigatus environmental isolates in Greece: detection of pan-azole resistance associated with the TR46/Y121F/T289A cyp51A mutation
Authors: Siopi Maria , Rivero-Menendez Olga , Gkotsis Georgios , Panara Anthi , Thomaidis Nikolaos S , Alastruey-Izquierdo Ana , Pournaras Spyros , Meletiadis Joseph
Published: June 2020

Background

Acquired azole resistance (AR) in Aspergillus fumigatus emphasizes the importance of the One Health multisectorial approach. The prevalence of azole-resistant A. fumigatus in the environment of Greece is unknown.

Methods

Between October 2016 and September 2017, a total of 716 soil samples were collected from 23 provinces and screened for AR using azole-containing agar plates. Recovered isolates were macro-/microscopically identified and colonies were counted. Azole susceptibility testing of A. fumigatus species complex (SC) isolates was performed (EUCAST E.DEF9.3.1). Azole-resistant A. fumigatus isolates were subjected to confirmatory molecular identification and sequencing of the cyp51A gene.

Results

No yeasts were recovered, while multiple moulds grew on 695 (97%) samples. Overall, zygomycetes (most non-Mucor genera) grew on 432 (60%) samples, while Aspergillus spp. grew on 500 (70%) [410 (57%) Aspergillus niger SC; 120 (17%) Aspergillus terreus SC; 101 (14%) A. fumigatus SC; 34 (5%) Aspergillus flavus SC]. The mean ± SD soil load of Aspergillus spp. was 2.23 ± 0.41 log10 cfu/g (no differences among species). No azole-resistant non-A. fumigatus spp. isolate was detected. Itraconazole, voriconazole, isavuconazole and posaconazole MIC50/MIC90 (MIC range) of A. fumigatus SC strains were 0.25/0.5 (0.25 to >8), 0.5/1 (0.25 to >8), 1/1 (0.125 to >8) and 0.06/0.125 (0.06–1) mg/L, respectively. Overall, 1/500 (0.2%) of Aspergillus isolates, and 1/101 (1%) of A. fumigatus SC isolates, was pan-azole-resistant (itraconazole, voriconazole, isavuconazole and posaconazole MIC >8, >8, >8 and 1 mg/L, respectively). The resistant isolate was recovered from organically grown raisin grapes treated with homemade compost and it was an A. fumigatus sensu stricto isolate harbouring the TR46/Y121F/T289A mutation. The soil’s load was higher compared with azole-susceptible strains (3.74 versus 2.09 log10 cfu/g).

Conclusions

This is the first known report of environmental pan-azole-resistant A. fumigatus in Greece. Since data on Greek clinical isolates are lacking, this finding must alarm the systematic local surveillance of AR in medical settings.
Telehealth in response to the COVID-19 pandemic: Implications for rural health disparities
Authors: Hirko Kelly A , Kerver Jean M , Ford Sabrina , Szafranski Chelsea , Beckett John , Kitchen Chris , Wendling Andrea L
Published: June 2020

Telehealth programs have long held promise for addressing rural health disparities perpetuated by inadequate healthcare access. The COVID-19 (coronavirus disease 2019) pandemic and accompanying social distancing measures have hastened the implementation of telehealth programs in hospital systems around the globe. Here, we provide specific examples of telehealth efforts that have been implemented in a large rural healthcare system in response to the pandemic, and further describe how the massive shift to telehealth and reliance on virtual connections in these times of social isolation may impact rural health disparities for those without access to necessary broadband to deploy digital technologies. Finally, we provide recommendations for researchers and policymakers to ensure that telehealth initiatives do not amplify existing health disparities experienced by those living in rural communities.
Timing of Flap Surgery in Acute Burn Patients Does Not Affect Complications
Authors: Perrault David , Rochlin Danielle , Pham Christopher , Momeni Arash , Karanas Yvonne , Sheckter Clifford C
Published: June 2020

Pedicled and free flaps are occasionally necessary to reconstruct complex wounds in acute burn patients. Flap coverage has classically been delayed for concern of progressive tissue necrosis and flap failure. We aim to investigate flap complications in primary burn care leveraging national U.S. data. Acute burn patients with known % total body surface area(TBSA) were extracted from the Nationwide/National Inpatient Sample from 2002 to 2014 based on the International Classification of Disease (ICD) codes, ninth edition. Variables included age, sex, race, Elixhauser index, %TBSA, mechanism, inhalation injury, and location of burn. Flap complication was defined by ICD-9 procedure code 86.75, return to the operating room for flap revision. Multivariable analysis evaluated predictors of flap compromise using stepwise logistic regression with backward elimination. The weighted sample included 306,924 encounters of which 526 received a flap (0.17%). About 7.8% of flap encounters sustained electric injury compared to 2.7% of non-flap encounters (odds ratio [OR] 3.76, 95% confidence interval [CI] 1.95–7.24, P < .001). The mean hospital day of the flap procedure was 10.1 (SD 10.7) days. Flap complications occurred in 6.4% of cases. The timing of flap coverage was not associated with complications. The only independent predictor of flap complication was electrical injury (OR 40.49, 95% CI 2.98–550.64, P = .005). Electrical injury was an independent predictor of flap complications compared to other mechanisms. Flap timing was not associated with return to surgery for complications. This suggests that the use of flaps is safe in acute burn care to achieve burn wound closure with an understanding that electrical injuries may warrant particular consideration to avoid failure.
Mortality From Burns Sustained on Home Oxygen Therapy Exceeds Predicted Mortality
Authors: Singer Kathleen E , Harvey Jalen A , Heh Victor , Dale Elizabeth L
Published: June 2020

The Boston Criteria and the Abbreviated Burn Severity Index are two widely accepted models for predicting mortality in burn patients. We aimed to elucidate whether these models are able to predict the risk of mortality in patients who sustain burns while smoking on home oxygen given their clinical fragility. We conducted a retrospective chart review of 48 patients admitted to our burn center from November 2013 to September 2017 who sustained a burn while smoking on home oxygen. Yearlong mortality was the primary outcome of the investigation; secondary outcomes included discharge to facility, length of stay, and need for tracheostomy. We calculated the expected mortality rate for each patient based on Boston Criteria and Abbreviated Burn Severity Index and compared the mortality rate observed in our cohort. Patients in our cohort suffered a 54% mortality rate within a year of injury, compared to a 23.5% mortality predicted by Boston Criteria, which was found to be statistically significant by chi-square analysis (P < .05). Abbreviated Burn Severity Index predicted mortality was 19.7%. While the absolute value of the difference in mortality was greater, this was not significant on chi-square analysis due to sample size. Our secondary outcomes revealed 42% discharge to facility, the average length of stay of 6.2 days, and 6.25% required tracheostomy. Patients whose burns are attributable to smoking on home oxygen may have an increased risk of mortality than prognostication models would suggest. This bears significant clinical impact, particularly regarding family and provider decision making in pursuing aggressive management.
Saturated models of first-order many-valued logics
Authors: Badia Guillermo , Noguera Carles
Published: June 2020

This paper is devoted to the problem of existence of saturated models for first-order many-valued logics. We consider a general notion of type as pairs of sets of formulas in one free variable that express properties that an element of a model should, respectively, satisfy and falsify. By means of an elementary chains construction, we prove that each model can be elementarily extended to a $\kappa $-saturated model, i.e. a model where as many types as possible are realized. In order to prove this theorem we obtain, as by-products, some results on tableaux (understood as pairs of sets of formulas) and their consistency and satisfiability and a generalization of the Tarski–Vaught theorem on unions of elementary chains. Finally, we provide a structural characterization of $\kappa $-saturation in terms of the completion of a diagram representing a certain configuration of models and mappings.
From Which Consumption-Based Asset Pricing Models Can Investors Profit? Evidence from Model-Based Priors
Authors: Kruttli Mathias S
Published: June 2020

This article analyzes whether consumption-based asset pricing models improve the excess returns forecasts of a hypothetical investor with access to these models from 1947 onwards. The investor imposes economic constraints derived from asset pricing models as model-based priors on predictive regression parameters through a Bayesian framework. Three models are considered: habit formation, long-run risk, and prospect theory. The model-based priors generally perform better than priors that shrink the parameter estimates to the historical average model and priors that impose a positive equity premium. This analysis helps to assess the value of consumption-based asset pricing models to investors.
Locally constant constructive functions and connectedness of intervals
Authors: Chernov Viktor
Published: June 2020

We prove that every locally constant constructive function on an interval is in fact a constant function. This answers a question formulated by Andrej Bauer [ 1]. As a related result, we show that an interval consisting of constructive real numbers is in fact connected but can be decomposed into the disjoint union of two sequentially closed nonempty sets.
High-sensitivity observations of molecular lines with the Arecibo Telescope
Authors: Tan W S , Araya E D , Lee L E , Hofner P , Kurtz S , Linz H , Olmi. L
Published: June 2020

We report on one of the highest sensitivity surveys for molecular lines in the frequency range 6.0–7.4 GHz conducted to date. The observations were done with the 305- m Arecibo Telescope toward a sample of 12 intermediate-/high-mass star-forming regions. We searched for a large number of transitions of different molecules, including CH3OH and OH. The low rms noise of our data ($\sim \!5\,$ mJy for most sources and transitions) allowed detection of spectral features that have not been seen in previous lower sensitivity observations of the sources, such as detection of excited OH and 6.7 GHz CH3OH absorption. A review of 6.7 GHz CH3OH detections indicates an association between absorption and radio continuum sources in high-mass star-forming regions, although selection biases in targeted projects and low sensitivity of blind surveys imply incompleteness. Absorption of excited OH transitions was also detected toward three sources. In particular, we confirm a broad 6.035 GHz OH absorption feature in G34.26+0.15 characterized by an asymmetric blueshifted wing indicative of expansion, perhaps a large-scale outflow in this H ii region.
GRANDMA observations of advanced LIGO’s and advanced Virgo’s third observational campaign
Authors: Antier S , Agayeva S , Almualla M , Awiphan S , Baransky A , Barynova K , Beradze S , Blažek M , Boër M , Burkhonov O , Christensen N , Coleiro A , Corre D , Coughlin M W , Crisp H , Dietrich T , Ducoin J-G , Duverne P-A , Marchal-Duval G , Gendre B , Gokuldass P , Eggenstein H B , Eymar L , Hello P , Howell E J , Ismailov N , Kann D A , Karpov S , Klotz A , Kochiashvili N , Lachaud C , Leroy N , Lin W L , Li W X , Mašek M , Mo J , Menard R , Morris D , Noysena K , Orange N B , Prouza M , Rattanamala R , Sadibekova T , Saint-Gelais D , Serrau M , Simon A , Stachie C , Thöne C C , Tillayev Y , Turpin D , Postigo A de Ugarte , Vasylenko V , Vidadi Z , Was M , Wang X F , Zhang J J , Zhang T M , Zhang X H
Published: June 2020

GRANDMA (Global Rapid Advanced Network Devoted to the Multi-messenger Addicts) is a network of 25 telescopes of different sizes, including both photometric and spectroscopic facilities. The network aims to coordinate follow-up observations of gravitational-wave (GW) candidate alerts, especially those with large localization uncertainties, to reduce the delay between the initial detection and the optical confirmation. In this paper, we detail GRANDMA’s observational performance during Advanced LIGO/Advanced Virgo Observing Run 3 (O3), focusing on the second part of O3; this includes summary statistics pertaining to coverage and possible astrophysical origin of the candidates. To do so, we quantify our observation efficiency in terms of delay between GW candidate trigger time, observations, and the total coverage. Using an optimized and robust coordination system, GRANDMA followed-up about 90 per cent of the GW candidate alerts, that is 49 out of 56 candidates. This led to coverage of over 9000 deg2 during O3. The delay between the GW candidate trigger and the first observation was below 1.5 h for 50 per cent of the alerts. We did not detect any electromagnetic counterparts to the GW candidates during O3, likely due to the very large localization areas (on average thousands of degrees squares) and relatively large distance of the candidates (above 200 Mpc for 60 per cent of binary neutron star, BNS candidates). We derive constraints on potential kilonova properties for two potential BNS coalescences (GW190425 and S200213t), assuming that the events’ locations were imaged.
Inhomogeneous He ii reionization in hydrodynamic simulations
Authors: Upton Sanderbeck Phoebe , Bird Simeon
Published: June 2020

The reionization of the second electron of helium shapes the physical state of intergalactic gas at redshifts between 2 ≲ z ≲ 5. Because performing full in situ radiative transfer in hydrodynamic simulations is computationally expensive for large volumes, the physics of He ii reionization is often approximated by a uniform ultraviolet background model that does not capture the spatial inhomogeneity of reionization. We have devised a model that implements the effects of He ii reionization using semi-analytic calculations of the thermal state of intergalactic gas – a way to bypass a full radiative transfer simulation while still realizing the physics of He ii reionization that affects observables such as the Lyman α forest. Here, we present a publicly available code that flexibly models inhomogeneous He ii reionization in simulations at a negligible computational cost. Because many of the parameters of He ii reionization are uncertain, our model is customizable from a set of free parameters. We show results from this code in mp-gadget, where this model is implemented. We demonstrate the resulting temperature evolution and temperature–density relation of intergalactic gas – consistent with recent measurements and previous radiative transfer simulations. We show that the impact of He ii reionization gives rise to subtle signatures in the 1D statistics of the Lyman α forest at the level of several percent, in agreement with previous findings. The flexible nature of these simulations is ideal for studies of He ii reionization and future observations of the He ii Lyman α forest.
Using quasar X-ray and UV flux measurements to constrain cosmological model parameters
Authors: Khadka Narayan , Ratra Bharat
Published: June 2020

Risaliti and Lusso have compiled X-ray and UV flux measurements of 1598 quasars (QSOs) in the redshift range 0.036 ≤ z ≤ 5.1003, part of which, z ∼ 2.4 − 5.1, is largely cosmologically unprobed. In this paper we use these QSO measurements, alone and in conjunction with baryon acoustic oscillation (BAO) and Hubble parameter [H(z)] measurements, to constrain cosmological parameters in six different cosmological models, each with two different Hubble constant priors. In most of these models, given the larger uncertainties, the QSO cosmological parameter constraints are mostly consistent with those from the BAO + H(z) data. A somewhat significant exception is the non-relativistic matter density parameter Ωm0 where QSO data favour Ωm0 ∼ 0.5 − 0.6 in most models. As a result, in joint analyses of QSO data with H(z) + BAO data the 1D Ωm0 distributions shift slightly towards larger values. A joint analysis of the QSO + BAO + H(z) data is consistent with the current standard model, spatially-flat ΛCDM, but mildly favours closed spatial hypersurfaces and dynamical dark energy. Since the higher Ωm0 values favoured by QSO data appear to be associated with the z ∼ 2 − 5 part of these data, and conflict somewhat with strong indications for Ωm0 ∼ 0.3 from most z < 2.5 data as well as from the cosmic microwave background anisotropy data at z ∼ 1100, in most models, the larger QSO data Ωm0 is possibly more indicative of an issue with the z ∼ 2 − 5 QSO data than of an inadequacy of the standard flat ΛCDM model.
Asymmetric dimerization of adenosine deaminase acting on RNA facilitates substrate recognition
Authors: Thuy-Boun Alexander S , Thomas Justin M , Grajo Herra L , Palumbo Cody M , Park SeHee , Nguyen Luan T , Fisher Andrew J , Beal Peter A
Published: June 2020

Adenosine deaminases acting on RNA (ADARs) are enzymes that convert adenosine to inosine in duplex RNA, a modification that exhibits a multitude of effects on RNA structure and function. Recent studies have identified ADAR1 as a potential cancer therapeutic target. ADARs are also important in the development of directed RNA editing therapeutics. A comprehensive understanding of the molecular mechanism of the ADAR reaction will advance efforts to develop ADAR inhibitors and new tools for directed RNA editing. Here we report the X-ray crystal structure of a fragment of human ADAR2 comprising its deaminase domain and double stranded RNA binding domain 2 (dsRBD2) bound to an RNA duplex as an asymmetric homodimer. We identified a highly conserved ADAR dimerization interface and validated the importance of these sequence elements on dimer formation via gel mobility shift assays and size exclusion chromatography. We also show that mutation in the dimerization interface inhibits editing in an RNA substrate-dependent manner for both ADAR1 and ADAR2.
DNA backbone interactions impact the sequence specificity of DNA sulfur-binding domains: revelations from structural analyses
Authors: Yu Hao , Li Jiayi , Liu Guang , Zhao Gong , Wang Yuli , Hu Wenyue , Deng Zixin , Wu Geng , Gan Jianhua , Zhao Yi-Lei , He Xinyi
Published: June 2020

The sulfur atom of phosphorothioated DNA (PT-DNA) is coordinated by a surface cavity in the conserved sulfur-binding domain (SBD) of type IV restriction enzymes. However, some SBDs cannot recognize the sulfur atom in some sequence contexts. To illustrate the structural determinants for sequence specificity, we resolved the structure of SBDSpr, from endonuclease SprMcrA, in complex with DNA of GPSGCC, GPSATC and GPSAAC contexts. Structural and computational analyses explained why it binds the above PT-DNAs with an affinity in a decreasing order. The structural analysis of SBDSpr–GPSGCC and SBDSco–GPSGCC, the latter only recognizes DNA of GPSGCC, revealed that a positively charged loop above the sulfur-coordination cavity electrostatically interacts with the neighboring DNA phosphate linkage. The structural analysis indicated that the DNA–protein hydrogen bonding pattern and weak non-bonded interaction played important roles in sequence specificity of SBD protein. Exchanges of the positively-charged amino acid residues with the negatively-charged residues in the loop would enable SBDSco to extend recognization for more PT-DNA sequences, implying that type IV endonucleases can be engineered to recognize PT-DNA in novel target sequences.
Bypass of DNA interstrand crosslinks by a Rev1–DNA polymerase ζ complex
Authors: Bezalel-Buch Rachel , Cheun Young K , Roy Upasana , Schärer Orlando D , Burgers Peter M
Published: June 2020

DNA polymerase ζ (Pol ζ) and Rev1 are essential for the repair of DNA interstrand crosslink (ICL) damage. We have used yeast DNA polymerases η, ζ and Rev1 to study translesion synthesis (TLS) past a nitrogen mustard-based interstrand crosslink (ICL) with an 8-atom linker between the crosslinked bases. The Rev1–Pol ζ complex was most efficient in complete bypass synthesis, by 2–3 fold, compared to Pol ζ alone or Pol η. Rev1 protein, but not its catalytic activity, was required for efficient TLS. A dCMP residue was faithfully inserted across the ICL-G by Pol η, Pol ζ, and Rev1–Pol ζ. Rev1–Pol ζ, and particularly Pol ζ alone showed a tendency to stall before the ICL, whereas Pol η stalled just after insertion across the ICL. The stalling of Pol η directly past the ICL is attributed to its autoinhibitory activity, caused by elongation of the short ICL-unhooked oligonucleotide (a six-mer in our study) by Pol η providing a barrier to further elongation of the correct primer. No stalling by Rev1–Pol ζ directly past the ICL was observed, suggesting that the proposed function of Pol ζ as an extender DNA polymerase is also required for ICL repair.
Hydroxychloroquine and azithromycin tolerance in haemodialysis patients during COVID-19 infection
Authors: Giaime Philippe , Guenoun Maxime , Pedinielli Nathalie , Narbonne Hervé , Bergounioux Jean-Philippe , Solas Caroline , Guilhaumou Romain , Sampol Jérôme , Ollier Jacques , Sichez Hélène , Serveaux Marianne , Brunner Flora , Bataille Stanislas
Published: June 2020

Background

Haemodialysis patients are at risk of developing severe forms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection: coronavirus disease 2019 (COVID-19). In March 2020, hydroxychloroquine (HCQ) and azithromycin (AZI) were proposed as potential treatments of COVID-19, but with warnings concerning their possible toxicity. No data are available regarding the toxicity of this treatment in haemodialysis patients.

Methods

We report the use of HCQ and AZI in a cohort of COVID-19 haemodialysis patients with focus on safety concerns.

Results

Twenty-one patients received 200 mg HCQ thrice daily during 10 days, and AZI 500 mg on Day 1, and 250 mg on the four following days. HCQ plasma concentrations were within the recommended range (0.1–1.0 µg/mL) in all patients except one, in which maximum concentration was 1.1 µg/mL. HCQ concentration raised until the third day and remained stable thereafter. No cardiac event occurred in spite of progressive lengthening of corrected QT interval (QTc) during the treatment. One patient experienced a long QTc syndrome (QTc >500 ms) without any arrhythmia episode, although HCQ concentration was in the target range. Five (23.8%) patients experienced hypoglycaemia, a well-known HCQ side-effect. SARS-CoV-2 RNA remained detectable in nasopharyngeal swabs for a long time in haemodialysis patients (mean time 21 days).

Conclusions

HCQ and AZI are safe in haemodialysis patients at these doses but can lead to long QTc syndrome and hypoglycaemia. HCQ concentrations were not correlated with side effects. We recommend monitoring of the QTc length throughout treatment, as well as glycaemia. SARS-CoV-2 could persist for longer in haemodialysis patients than in the general population.
Missing diversity in brain tumor trials
Authors: Taha Birra , Winston Graham , Tosi Umberto , Hartley Benjamin , Hoffman Caitlin , Dahmane Nadia , Mason Christopher E , Greenfield Jeffrey P
Published: June 2020

Background

Clinical trials for brain tumors represent a significant opportunity for both patients and providers to understand and combat a disease with substantial morbidity. The aim of this study was to quantify and map ethnic and racial representation in brain tumor trials and examine the potential gaps in trial recruitment. We also show that these representation gaps persist even in large multicultural cities like New York City.

Methods

We analyzed brain tumor clinical trials registered on www.clinicaltrials.gov between July 1, 2005 and completed on or before November 11, 2017. We used a combination of PubMed/MEDLINE and Google Scholar to find associated publications and obtained trial information as well as patient demographic information (when available) including race or ancestry.

Results

Out of 471 trials, 27% had no published results. Only 28.4% of trials with results reported race or ethnicity of trial participants, with no observed upward trend by year. Whites were significantly overrepresented in trials for metastatic brain tumors (P < .001) and high-grade trials (P < .001). Blacks/African Americans (AAs), Hispanics, and Asians were significantly underrepresented (P < .001) in high-grade trials, while only Blacks/AAs were underrepresented in trials for metastatic brain tumors (P < .001). Representation gaps were not observed in pediatric trials. Despite being a multicultural hub, New York City displayed similar gaps in trial representation.

Conclusions

Despite increasing representation in the American population, minorities are underrepresented in brain tumor trials. In addition, despite numerous legal requirements and ethical mandates, published results including race-based information are remarkably absent from 70% of brain tumor trials.
René Girard
Authors: Palaver Wolfgang
Published: June 2020

René Noël Théophile Girard (b. 25 December 1923 in Avignon, d. 4 November 2015 in Stanford) was a French-American cultural anthropologist who discovered in the works of European novelists like Cervantes, Flaubert, Stendhal, Proust, and Dostoevsky the important impact of imitative desire on human relations. This insight became the basis for his mimetic theory, an anthropological approach that has not only helped to interpret literature, but has also become a theoretical tool to understand the development of human culture and particularly the role of religion in it. By distinguishing between the sacred of early religions and the holy as the core of the Judeo-Christian tradition, mimetic theory provides a theory of religion that contributes also to a better understanding of the post-Axial religions. Mimetic theory, however, reaches far beyond literature and religion, as its application in fields like anthropology, psychology, theology, and history as well as political and economic theory shows. Similar to the broad outreach of mimetic theory, also Girard himself entered many different scholarly disciplines. He studied medieval and modern history before he entered fields like literary criticism, religious and classical studies, and biblical literature. In 1947, he graduated with a dissertation on marriage and private life in 15th-century Avignon as an archiviste-paléographe from the École des Chartes in Paris. Soon afterward, he left for the United States to study contemporary history at Indiana University, where he received his PhD with a dissertation on “American Opinion on France, 1940–1943” in 1950. After working as an instructor of French literature at Duke University (1952) and as an assistant professor at Bryn Mawr College (1953–1957), he held professorships at Johns Hopkins University (1957–1968; 1976–1981), in the Department of English at SUNY Buffalo (1986–1976), and finally at Stanford University (1981–1995). He received honorary degrees and awards from many different universities and academic institutions and was elected in 2005 to the Académie française. His mimetic theory consists mainly of four stages: (1) mimetic desire as he discovered it in great literature; (2) the scapegoat mechanism as the origin of human culture and early religions; (3) his theory of religion, which distinguishes between the sacred of early religions and the holiness that characterized the Judeo-Christian tradition; and (4) finally his apocalyptic view of history, which started with a chapter on Dostoevsky in his first book and culminated in his reflections on Clausewitz’s theory of war in his last book.
Olaudah Equiano
Authors: Wagner Bryan , Kjellin-Elder Parker
Published: June 2020

Olaudah Equiano, or Gustavus Vassa, as he was known during his lifetime (b. 1745?–d. 1797), was a writer and polemicist of extraordinary abilities. His Interesting Narrative informs readers that he was born into a ruling-class Igbo family in 1745 and was kidnapped at the age of eleven. He tells readers that he was then sold to Europeans on the Gold Coast and made to endure the dreaded transatlantic Middle Passage to Virginia. After this time, he was sold to Michael Henry Pascal, an officer in the British Royal Navy, who, against Equiano’s will, named him Gustavus Vassa, a name that Equiano used throughout the rest of his life. Traveling with Pascal to England, Equiano was officially baptized, he tells us, in 1759. After his baptism, Pascal recruited Equiano for the Seven Years’ War. Equiano mistakenly assumed that Pascal would free him at the end of the conflict. Instead, Pascal sold him into West Indian slavery. From there, Equiano worked to save enough money and purchase his own manumission in 1766. With his new freedom, Equiano sailed the world, gaining the rank of able seaman, as he traveled across the Atlantic and even to the North Pole. After that harrowing journey, Equiano experienced a spiritual conversion to Methodism in 1774, and grew publicly involved with the antislavery debate, through letters, speeches, and his own Interesting Narrative. He married a white Englishwoman, Susanna Cullen, in 1792, and had two daughters, only one of whom survived to inherit the estate that Equiano left for her when he died on 31 March 1797. Biographer Vincent Carretta suggests that aspects of Equiano’s life story, including his African nativity, may be fabricated, as Equiano’s baptismal record lists him as “a Black born in Carolina 12 years old,” a possibility supported by one ship’s muster logs. Following on Carretta’s research, critics continue to debate important questions about genre, evidence, imagination, authenticity, testimony, and authorship.