bluuebunny/crossref_metadata_2025 huggingface dataset:
Macromolecular regulators have matching effects on the phase equilibrium and interfacial tension of biomolecular condensates
Authors: Mazarakos Konstantinos , Zhou Huan‐Xiang
Published: April 2021

The interfacial tension of phase‐separated biomolecular condensates affects their fusion and multiphase organization, and yet how this important property depends on the composition and interactions of the constituent macromolecules is poorly understood. Here we use molecular dynamics simulations to determine the interfacial tension and phase equilibrium of model condensate‐forming systems. The model systems consist of binary mixtures of Lennard‐Jones particles or chains of such particles. We refer to the two components as drivers and regulators; the former has stronger self‐interactions and hence a higher critical temperature (Tc) for phase separation. In previous work, we have shown that, depending on the relative strengths of driver‐regulator and driver‐driver interactions, regulators can either promote or suppress phase separation (i.e., increase or decrease Tc). Here we find that the effects of regulators on Tc quantitatively match the effects on interfacial tension (γ). This important finding means that, when a condensate‐forming system experiences a change in macromolecular composition or a change in intermolecular interactions (e.g., by mutation or posttranslational modification, or by variation in solvent conditions such as temperature, pH, or salt), the resulting change in Tc can be used to predict the change in γ and vice versa. We also report initial results showing that disparity in intermolecular interactions drives multiphase coexistence. These findings provide much needed guidance for understanding how biomolecular condensates mediate cellular functions.
Tailoring of Magnetic Softness and Magnetoimpedance of Co‐Rich Microwires by Stress Annealing
Authors: Zhukov Arcady , Gonzalez-Legarreta Lorena , Corte-Leon Paula , Ipatov Mihail , Maria Blanco Juan , Gonzalez Julian , Zhukova Valentina
Published: April 2021

Herein, detailed studies on the influence of stress annealing on the magnetic softness and giant magnetoimpedance (GMI) ratio of Co69.2Fe3.6Ni1B12.5Si11Mo1.5C1.2 glass‐coated microwires are provided. As‐prepared microwire presents linear hysteresis loops, moderate GMI ratio with double‐peak magnetic field dependence and low coercivity (4 A m−1), typically observed for wires with transverse magnetic anisotropy. However, after conventional annealing magnetic hardening and transformation of linear hysteresis loop into rectangular with coercivity about 90 A m−1 is surprisingly observed. It is shown that stress annealing allows preventing magnetic hardening and remarkably improving GMI ratio. Properly stress‐annealed samples present better magnetic softness: almost unhysteretic loops with coercivity about 2 A m−1 and magnetic anisotropy field about 35 A m−1. Observed stress‐annealing‐induced anisotropy is affected by the tensile stresses, applied during annealing and by the annealing temperature. From the frequency dependence of the maximum GMI ratio, the optimum frequency ranges for as‐prepared and stress‐annealed samples are determined. The observed stress‐annealing‐induced magnetic anisotropy and associated changes in magnetic properties and GMI effect are discussed in terms of internal stresses relaxation and related modification of the magnetostriction coefficient, “back stresses,” structural anisotropy, redistribution of internal stresses, and change of spatial distribution of magnetic anisotropy.
Effectiveness of supplementation with quercetin‐type flavonols for treatment of viral lower respiratory tract infections: Systematic review and meta‐analysis of preclinical studies
Authors: Brito Júlio César Moreira , Lima William Gustavo , Cordeiro Lídia Pereira B. , da Cruz Nizer Waleska Stephanie
Published: April 2021

Viral infections of the lower respiratory tract are considered a public health problem. They affect millions of people worldwide, causing thousands of deaths, and are treated with expensive medicines, such as antivirals or palliative measures. In this study, we conducted a systematic review to describe the use of quercetin‐type flavonols against lower respiratory tract viruses and discussed the preclinical impact of this approach on different signs and clinical mechanisms of infection. The systematic review was performed in PubMed/MEDLINE, Scopus, Scielo, and Biblioteca Virtual de Saúde (BVS). After the database search, 11 relevant studies were identified as eligible. The analysis of these studies showed evidence of antiviral activity of quercetin‐type flavonols with significantly reduced mortality rate (M‐H = 0.19, 95% CI: 0.05 to 0.65, p‐value = 0.008) of infected animals and a reduction in the average viral load (IV = −1.93, 95% CI: −3.54 to −0.31, p‐value = 0.02). Additionally, quercetin and its derivatives reduced the amount of proinflammatory cytokines, chemokines, reactive oxygen species, mucus production, and airway resistance in animals infected with a respiratory virus. Overall, supplementation with quercetin‐type flavonols is a promising strategy for treating viral‐induced lower respiratory tract infections.
Optimizing sulfate pyrolysis triple oxygen isotope analysis for samples from desert environments
Authors: Klipsch Swea , Herwartz Daniel , Staubwasser Michael
Published: April 2021

Rationale

The triple oxygen isotope composition of sulfate may reveal the formation pathway and depositional sources and may indicate slow biologic cycling in the environment. Pyrolysis mass spectrometry is better suited for large sample workloads during environmental profiling but sufficient precision and a thorough verification of accuracy are required for comparison with higher precision laser fluorination data.

Methods

Quantitative sulfate extraction from soil samples at neutral pH, purification, conversation into Ag‐sulfate, and pyrolysis mass spectrometry were modified for high sample throughput. Samples were analyzed after pyrolysis in quartz cups and gold capsules in a modified EuroVector model 3000 elemental analyzer. Sample O2 was measured in continuous He‐flow after purification by cryo‐trapping and chromatography on a Thermo Finnigan MAT253 isotope ratio mass spectrometer. A protocol for routine quality control and data normalization ensures long‐term accuracy of the pyrolysis method.

Results

The 1σ SD external reproducibility is 0.12‰ for Δ17OSO4 values on 30 μmol samples. Careful normalization for a daily analytical session accounts for changing pyrolysis conditions over the course of multiple sessions. The precision and accuracy obtained with quartz cups are comparable with those obtained with gold capsules. Pyrolysis and fluorination data for in‐house standards from four laboratories and from an Atacama Desert gypsum‐soil profile are identical and demonstrate the accuracy of our simplified method.

Conclusions

Pyrolysis of sulfate in quartz cups and a modified simple elemental analyzer setup allows for accurate, precise, fast, cost‐efficient, and non‐hazardous mass spectrometric analysis. Exchangeability of data from pyrolysis and laser fluorination methods was demonstrated by repeat analysis of standards and natural samples despite high contents of interfering, easily soluble nitrates and chlorides.
Improving memory effect correction to achieve high‐precision analysis of δ17O, δ18O, δ2H, 17O‐excess and d‐excess in water using cavity ring‐down laser spectroscopy
Authors: Vallet‐Coulomb Christine , Couapel Martine , Sonzogni Corinne
Published: April 2021

Rationale

The precision obtained in routine isotope analysis of water (δ17O, δ18O, δ2H, 17O‐excess and d‐excess values) using cavity ring‐down spectroscopy is usually below the instrument specifications provided by the manufacturer. This study aimed at reducing this discrepancy, with particular attention paid to mitigating the memory effect (ME).

Methods

We used a Picarro L2140i analyzer coupled with a high‐precision A0211 vaporizer and an A0325 autosampler. The magnitude and duration of the ME were estimated using 24 series of 50 successive injections of samples with contrasting compositions. Four memory correction methods were compared, and the instrument performance was evaluated over a 17‐month period of routine analysis, using two different run architectures.

Results

The ME remains detectable after the 30th injection, implying that common correction procedures only based on the last preceding sample need to be revised. We developed a new ME correction based on the composition of several successive samples, and designed a run architecture to minimize the magnitude of the ME. The standard deviation obtained from routine measurement of a quality assurance water sample over a seven‐month period was 0.015‰ for δ17O, 0.023‰ for δ18O, 0.078‰ for δ2H, 0.006‰ for 17O‐excess and 0.173‰ for d‐excess. In addition, we provided the first δ17O and 17O‐excess values for the GRESP certified reference material.

Conclusions

This study demonstrates the long‐term persistence of the ME, which is often overlooked in routine analysis of natural samples. As already evidenced when measuring labelled water, it calls for consideration of the compositions of several previous samples to obtain an appropriate correction, a prerequisite to achieve high‐precision data.
Effects of Heteroatom Doping of Carbon Dots from Sugar on Optical Properties, Phenolic Content, Antioxidant Activity, Photostability, and Cytotoxicity
Authors: Supjaroenpisan Monthakarn , Hanchaina Rattanavinan , Kangsamaksin Thaned , Paoprasert Peerasak
Published: April 2021

Carbon dots (CDs) are fascinating nanomaterials with technologically relevant properties; however, the effects of heteroatom doping on several properties of CDs have not been studied. In this work, a facile method for the synthesis and heteroatom doping of carbon dots from table sugar was developed using nitric acid, phosphoric acid, and sulfuric acid as simultaneous catalysts and dopants. The optical properties, phenolic content, antioxidant activity, photostability, and cytotoxicity of the CDs were measured and compared. L‐ascorbic acid, a well‐known antioxidant, and avobenzone and oxybenzone, common UV absorbers in sunscreens, were used for comparison. Interestingly, heteroatom doping has adverse effects on several properties of the CDs as the undoped CDs yielded the highest UV‐vis absorption, phenolic content, antioxidant activity, photostability, and biocompatibility. Only fluorescence quantum yields were improved by heteroatom doping. These findings will be crucial for choosing precursors for the synthesis of CDs because heteroatoms inherently present in precursors can have negative effects on the properties of the resulting CDs.
Scalable Single‐Crystalline Organic 1D Arrays for Image Sensor
Authors: Qiu Yuchen , Zhao Yuyan , Gao Hanfei , Zhao Yingjie , Zhang Jingyuan , Zhang Bo , Feng Jiangang , Jiang Lei , Wu Yuchen
Published: April 2021

Optoelectronic applications of organic semiconductors demand single‐crystalline structures with long‐range order and suppressed defects for sustaining efficient carrier transport and long photocarrier lifetime, which are pivotal in photodetection, photovoltaic, and light emission. For integrated devices, an additional requirement of precise patterning is imposed, whereas the patterning of single‐crystalline organic microstructures is still challenging because the molecular stacking is easily perturbed by disordered fluids in microdroplets. Herein, a capillary‐bridge lithography is developed for driving the directional transport of capillary flows to control the confined crystallization of organic 1D single‐crystalline arrays with aligned positioning and pure orientation. Through tuning the concentration and pressure, the size of organic 1D arrays in three dimensions can be controlled with 2.9–5.8 µm in width and 1.2 µm to 110 nm in height. Organic 1D array photodetectors exhibit a stable performance with on/off ratio of 180 and responsivity of 4.99 mA W−1. Based on the scalable fabrication of 1D array photodetectors, 20 × 20 multiplexed image sensors with high accuracy are demonstrated for capturing the light signals of capital letter “A,” “B,” and “C.” This research will open opportunities for the large‐scale fabrication of organic single‐crystalline semiconductors toward the integrated optoelectronic modules.
Single‐Cell Sequencing Methodologies: From Transcriptome to Multi‐Dimensional Measurement
Authors: Chen Yingwen , Song Jia , Ruan Qingyu , Zeng Xi , Wu Lingling , Cai Linfeng , Wang Xuanqun , Yang Chaoyong
Published: April 2021

Cells are the basic building blocks of biological systems, with inherent unique molecular features and development trajectories. The study of single cells facilitates in‐depth understanding of cellular diversity, disease processes, and organization of multicellular organisms. Single‐cell RNA sequencing (scRNA‐seq) technologies have become essential tools for the interrogation of gene expression patterns and the dynamics of single cells, allowing cellular heterogeneity to be dissected at unprecedented resolution. Nevertheless, measuring at only transcriptome level or 1D is incomplete; the cellular heterogeneity reflects in multiple dimensions, including the genome, epigenome, transcriptome, spatial, and even temporal dimensions. Hence, integrative single cell analysis is highly desired. In addition, the way to interpret sequencing data by virtue of bioinformatic tools also exerts critical roles in revealing differential gene expression. Here, a comprehensive review that summarizes the cutting‐edge single‐cell transcriptome sequencing methodologies, including scRNA‐seq, spatial and temporal transcriptome profiling, multi‐omics sequencing and computational methods developed for scRNA‐seq data analysis is provided. Finally, the challenges and perspectives of this field are discussed.
Isomer‐Dependent Photovoltaic Properties of the [6,6]‐Phenyl‐C61 (or C71)‐Butyric Acid Methyl Esters
Authors: Deng Lin-Long , Zhan Xin-Xing , Lin Jheng-Wei , Ho Rong-Ming , Zheng Lan-Sun , Xie Su-Yuan
Published: April 2021

Isomerism is common in fullerene derivatives, and the isomer‐dependent photovoltaic performance of fullerene derivatives is envisaged recently. This review article outlines recent progresses on isomerism of [6,6]‐phenyl‐C61 (or C71)‐butyric acid methyl esters (PCBMs), one of the most prevalent electronic acceptors in organic or perovskite solar cells. Recent developments about the effects of PCBMs isomers on the photovoltaic performance and device stability of organic or perovskite solar cells are summarized, including the mono‐ and bis‐adduct of PC71BM as well as the bis‐adduct of PC61BM. The open questions and future directions with involvement of isomeric PCBMs are also discussed.
Highly Efficient Solar Steam Generators Based on Multicore@Shell Nanostructured Aerogels of Carbon and Silica as the Light Absorber−Heat Insulator
Authors: Karami Sogol , Arabpour Roghabadi Farzaneh , Pashaei Soorbaghi Fatemeh , Ahmadi Vahid , Sadrameli Seyed Mojtaba
Published: April 2021

Herein, highly efficient, low‐cost, and lightweight solar steam generation systems are fabricated using engineered carbon and silica‐based porous nanostructures with 3D networks as light absorber and heat insulator, respectively. In this regard, systems with three different designs are considered to localize the heat efficiently through harvesting more photons and reducing heat losses. The fabricated systems are multilayered structures including polymeric foam and felt as the substrate and water‐carrier medium, respectively. Highly porous nanostructured particles of carbon aerogel (CA) as an absorber, silica aerogel (SiA) as a superinsulator, and multicore@shell aerogel of CA and SiA (CA core−SiA shell) as both absorber and insulator are synthesized. The used architectures are double layered (substrate covered by CA), triple layered (substrate covered by a layer of CA and a layer of SiA), and multicore@shell (substrate covered by CA−SiA multicore@shell aerogel). Using the double‐layered system, an efficiency of 83% corresponding to 1.2 kg m−2 h−1 water evaporation rate is achieved, which is enhanced to 90% in the triple‐layered system, where the SiA superinsulator is added. Remarkably, when the multicore@shell absorber−insulator is used, the efficiency increments of 27% and 16% are achieved compared with the double‐layered and triple‐layered ones with the same amount of absorber, respectively.
Effect of Temperature and Multichannel Stopper Rod on Bubbles in Water Model of a Steel Continuous Caster
Authors: Liu Fenggang , Zhou Haichen , Zhang Lifeng , Ren Changyu , Zhang Ji , Ren Ying , Chen Wei
Published: April 2021

Herein, effects of the water temperature and a multichannel stopper rod with various gas hole diameters on the size and distribution of bubbles are investigated using a 0.5‐scale water model of a steel slab continuous casting mold. The breakage ratio of bubbles increases with the increasing of the water temperature. The mean diameter of bubbles decreases from 2.11 to 1.32 mm with the water temperature increasing from 25 to 34 °C. The smaller dynamic viscosity and surface tension of the water at a higher temperature result in large turbulence velocity fluctuation at the bottom of the submerged entry nozzle. The effect of water temperature on the bubble size and distribution can hardly be ignored in the water model experiment. With the increase of the hole diameter of the gas channel (Dh) of the stopper rod, the number of bubbles first decreases to the minimum value atDh = 1.5 mm and then increases, and bubble mean diameters increase, and the horizontal dispersion and penetration depth increase when the bubble diameter is larger than 1 mm. The multichannel stopper rod with the gas hole diameter of 1.5 mm is recommended under the current specific continuous casting condition.
Enhanced Grain Refinement of W18Cr4V High‐Speed Steel Using in Situ TiN−Nb−Cr@Graphene/Fe Nanocomposite Inoculant
Authors: Bai Lina , Cui Chunxiang , Zhang Jianjun , Zhao Lichen , Zheng Guixing , Cui Sen
Published: April 2021

Traditional cast W18Cr4V high‐speed steel (HSS) undergoes elemental segregation during solidification, which deteriorates its macroscopic mechanical properties. Previous reports have demonstrated that grain refinement overcomes this issue. Therefore, herein, the effect of an Fe‐based nanocomposite inoculant on carbide dispersion is investigated. The inoculant comprises graphene‐coated ceramic particles prepared in situ via mechanical grinding in a ball grinder, where material thermodynamics are considered. The microstructure of the inoculated W18Cr4V HSS is analyzed using transition electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, and X‐ray diffraction. The orientation relationship among the phases is . The nanocomposite ceramic particles serve as a base for the heterogeneous nucleation of Fe3W3C and Fe3C, thereby increasing the nonuniform nucleation rate for enhanced grain refinement. This behavior plays a crucial role in the intragranular reinforcement of HSS.
Realizing of Anisotropic Wetting and Superhydrophobicity on Stainless Steel Surface by Combining Picosecond Laser Ablation and Electrodeposition
Authors: Hu Mengnan , Xu Kun , Zhang Zhaoyang , Gao Jian , Wang Tao , Dai Xueren , Zhu Hao
Published: April 2021

Superhydrophobic surface with anisotropic wetting and no low‐surface‐energy modification is investigated in which laser ablation, ultrasonic cleaning with degreasing solution, and electrodeposition are used sequentially. The macrogrooves are prepared by laser, and the micro–nanoscale structures on macrogrooves are prepared by electrodeposition, which is important to study the effect of hierarchical structures on anisotropic wetting. Herein, the surface morphology and surface crystal structure are discussed with respect to the laser‐ablated surface and the subsequent degreasing solution super‐cleaning/electrodeposited surfaces. At the same time, stainless steel surfaces with grooves of different periodic intervals (30–150 μm) and depths (10–40 μm) are systematically fabricated by laser only. When the periodic interval is smaller (<=50 μm), the static anisotropy is not obvious (5°–7°). However, the smaller the groove periodic interval and the greater the depth (<=30 μm), the more obvious the sliding anisotropy. Finally, dense and uniform micro–nanostructures on laser‐ablated grooves are prepared by electrodeposition. The micro–nanohierarchical structures prepared by electrodeposition not only can make the droplets have superhydrophobic properties but also enhance the water drop's anisotropic sliding ability.
Precocious Maturation in Spring‐Run Chinook Salmon Is Affected by Incubation Temperature, Feeding Regime, and Parentage
Authors: Winsor Stephen , Blumenshine Steve , Adelizi Paul , Bigelow Matt
Published: April 2021

Salmonid populations of the Central Valley of California have been in decline for decades, making hatchery practices that combine conservation strategies with targeted research essential to optimize recruitment to adulthood. Hatchery populations generally exhibit a higher incidence of precocious male maturation than natural populations. However, optimal hatchery management practices pertaining to incubation, feeding, and genetic predisposition have yet to be optimized to lower the incidence of precocity in hatchery‐reared male spring‐run Chinook Salmon Oncorhynchus tshawytscha. To further assess this, we conducted a 2 × 2 factorial experiment exploring the effect of embryo incubation temperature (cold or warm) and post‐ponding ration (high or low) on incidence of age‐1 precocious male maturation. Fertilized eggs from each parental cross were placed among each treatment group to control for genetic variation and track any genetic predisposition. Precocity rate at year 1 was affected by incubation temperature and feed rate. There were also significant differences in growth rate and body condition among the treatment groups during early development. Additionally, the precocious males were nonrandomly produced by the crosses, suggesting a significant parentage effect on precocity. Optimization of Chinook Salmon rearing techniques is critical—not only to lessen the incidence of precocity and identify the causal parameters, but also to maximize successful reintroduction.
Z‐scores of fetal bladder size for antenatal differential diagnosis between posterior urethral valves and urethral atresia
Authors: Fontanella F. , Groen H. , Duin L. K. , Suresh S. , Bilardo C. M.
Published: April 2021

Objective

To construct reference values for fetal urinary bladder distension in pregnancy and use Z‐scores as a diagnostic tool to differentiate posterior urethral valves (PUV) from urethral atresia (UA).

Methods

This was a prospective cross‐sectional study in healthy singleton pregnancies aimed at constructing nomograms of fetal urinary bladder diameter and volume between 15 and 35 weeks' gestation. Z‐scores of longitudinal bladder diameter (LBD) were calculated and validated in a cohort of fetuses with megacystis with ascertained postnatal or postmortem diagnosis, collected from a retrospective, multicenter study. Correlations between anatomopathological findings, based on medical examination of the infant or postmortem examination, and fetal megacystis were established. The accuracy of the Z‐scores was evaluated by receiver‐operating‐characteristics (ROC)‐curve analysis.

Results

Nomograms of fetal urinary bladder diameter and volume were produced from three‐dimensional ultrasound volumes in 225 pregnant women between 15 and 35 weeks of gestation. A total of 1238 urinary bladder measurements were obtained. Z‐scores, derived from the fetal nomograms, were calculated in 106 cases with suspected lower urinary tract obstruction (LUTO), including 76 (72%) cases with PUV, 22 (21%) cases with UA, four (4%) cases with urethral stenosis and four (4%) cases with megacystis‐microcolon‐intestinal hypoperistalsis syndrome. Fetuses with PUV showed a significantly lower LBD Z‐score compared to those with UA (3.95 vs 8.83, P < 0.01). On ROC‐curve analysis, we identified 5.2 as the optimal Z‐score cut‐off to differentiate fetuses with PUV from the rest of the study population (area under the curve, 0.84 (95% CI, 0.748–0.936); P < 0.01; sensitivity, 74%; specificity, 86%).

Conclusions

Z‐scores of LBD can distinguish reliably fetuses with LUTO caused by PUV from those with other subtypes of LUTO, with an optimal cut‐off of 5.2. This information should be useful for prenatal counseling and management of LUTO. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
The effect of Ag, ZnO, and CuO nanoparticles on the properties of the compatibilized polyethylene/thermoplastic starch blend films
Authors: Ozdemir Elif , Orkan Ucar Ikrime , Akay Ramiz Gultekin , Aytac Ayse
Published: April 2021

In this study, the effects of Ag, ZnO, and CuO nanoparticles (NPs) on the mechanical, thermal, and biodegradability properties of the compatibilized polyethylene (PE)/thermoplastic starch (TPS) blends were investigated. Polyethylene‐grafted maleic anhydride (PE‐g‐MA) was used as the compatibilizer. The compatibilized PE/TPS blends with different NPs were prepared by melt mixing method in a laboratory scale extruder and then pressurized in the press machine. The use of ZnO NP together with the compatibilizer in PE/TPS‐based films significantly increased the tensile stress values. The use of different type NPs did not cause any significant change in the thermal stability of PE/TPS‐based films. However, the effects of NPs were observed on the TPS degradation steps. The prepared films with different NPs showed an antibacterial activity between 60% and 70%. The highest crystallinity value was obtained in Ag NP containing films, among others. According to scanning electron microscopy analysis, better distribution was observed for ZnO and Ag NPs than CuO NP. In general, it can be said that the addition of NPs to PE/TPS‐based blends significantly reduces the partial biodegradability of the resulting films.
Coastal Surveillance and Water Quality monitoring in the Rejiche Sea—Tunisia
Authors: Alibi Sana , Beltifa Asma , Hassen Wafa , Jaziri Ahlem , Soussia Lotfi , Zbidi Fairouz , Ben Mansour Hedi
Published: April 2021

The aim of this study is to determine physiochemical and bacteriological properties of seawater and sediments from the coast of Tunisia during six successive months. The conductivity was measured using previously calibrated Hach Conductivity meter. Total suspended solid was determined using Whatman GF/C glass fiber filter (Sigma Aldrich), and the turbidity was assessed using a spectrophotometer (UV/Vis). The pH was measured using pH electrodes. Other physiochemical parameters were determined using Pastel UV multiparameter water analyzer (Secomam, aqualabo). Bacterial analysis was displayed by membrane filtration method, and isolates were identified to the species level by Api strips. Susceptibility to antibiotics was determined by disk diffusion methods. Total suspended solid, turbidity, adsorbable organic halogen, chemical oxygen demand, and biochemical oxygen demand were higher than accepted norms in Tunisia. Enterococcus faecalis was detected in all the sites indicating a human fecal contamination, and all the isolates were highly resistant to rifampicin, gentamicin, chloramphenicol, ampicillin, and azithromycin. The situation in Mahdia coast is alarming particularly with the isolation of multidrug resistance strains. It is recommended that the local government provide restrict policies for the treatment and the assessment of municipal wastewater before its discharge into sea.

Practitioner points

Coastal Surveillance and Water Quality monitoring in the Rejiche Sea – Tunisia is crucial.

Enterococcus faecalis was detected in sea water and sediment samples in the coast of Rejiche.

Isolated strains were highly resistant to rifampicin, gentamicin, chloramphenicol, ampicillin and azithromycin.
Climate change impacts on precipitation and temperature in Prince Edward Island, Canada
Authors: Bhatti Ahmad Zeeshan , Farooque Aitazaz Ahsan , Krouglicof Nicholas , Peters Wayne , Acharya Bishnu , Li Qing , Ahsan M. Sheraz
Published: April 2021

To understand climate change impacts on Prince Edward Island (PEI), Canada, historical daily precipitation and temperature of the island was investigated between the periods: 1931–60 (1940s), 1961–90 (1970s), and 1991–2020 (2000s) in its eastern, central, and western parts. Observed climatic data were utilized, augmented by some validated modeled data of Pacific Climate Impact Consortium (PCIC) for missing years. Statistically significant warming of the island was found ranging from 1.14°C in the east to 0.75°C in the west from the 1970s to 2000s. The warming trend during the period was distributed throughout the year including winters. In the east, mean monthly temperature significantly increased in all the months except for January, March, and June. Significant increase in temperature was found solely during August (+0.80°C) in central, and for August (+0.64°C), September (+0.99°C), and October (+0.73°C) in western parts. Proportionate increase in annual minimum temperature was greater than the maximum, particularly in eastern (+1.57°C) and central (+0.75°C) parts and thus indicated moderated cold there. Over the same 30‐year period, annual precipitation increased 6 percent in the east but decreased 5 and 8 percent in the central and the western PEI, respectively. The changes in precipitation were not statistically significant, except snowfall reduction (−20%) in the west, which was a statistically significant change. Interannual precipitation variations during wet and dry years having 20 and 80 percent probabilities of exceedance, respectively, ranged 350–470 mm/year during 1991–2020. Rainfall intensities, measured by hourly data, increased from 1.15 to 2.24 mm/hr, on average in central and western parts, respectively, in 2004–17 compared to 1970s. Impacts of the rising temperatures, decreasing precipitation, and uneven and intense rainfalls patterns on water resources and rainfed agriculture need further investigations. Climate change adaptations be included in existing water policies to mitigate the impacts.
Assessing saddle‐billed stork (Ephippiorhynchus senegalensis) pair‐bonds and breeding behavior using behavior observed during multiple breeding seasons
Authors: Weibel Chelsea J. , Abreu Rebecca , Becker Kris K. , Solomon Melissa , Ferrie Gina M.
Published: April 2021

Despite the fact that saddle‐billed storks (SBS) are housed in zoos around the world, few successful hatches have been recorded. At Disney's Animal Kingdom® we conducted observations on two pairs of SBS during multiple reproductive periods to assess the relative strength of their pair‐bonds and their reproductive success. We accomplished this through observations of rates of social behaviors, such as wing displays and aggression, rates of nest construction, time on and near the nest, and egg production. We determined that one pair was more successful than the other because it produced and incubated eggs during all breeding seasons. We found that the male from this more successful pairing displayed higher rates of nest presence, nest construction, and time on the nest than all other individuals. The more successful pairing also spent more time in close proximity than the less successful pair. During incubation, the male and female from the more successful pair spent similar amounts of time at the nest and incubating the eggs, but this pair never successfully hatched an egg during our study period. Ultimately, our results suggest that the pair‐bond between the more successful pair was stronger than that of the other pair because they spent more time in close proximity and performed higher rates of nesting behaviors. This study highlights the lack of understanding of the factors that lead to successful SBS pairings in zoos, and emphasizes the need for future studies of their nesting behavior and pair compatibility to increase reproductive success.
A closer look at CP-violating Higgs portal dark matter as a candidate for the GCE
Authors: Fraser Katherine , Parikh Aditya , Xu Weishuang Linda
Published: April 2021

Abstract

A statistically significant excess of gamma rays has been reported and robustly confirmed in the Galactic Center over the past decade. Large local dark matter densities suggest that this Galactic Center Excess (GCE) may be attributable to new physics, and indeed it has been shown that this signal is well-modelled by annihilations dominantly into $$ b\overline{b} $$
b

b
¯

with a WIMP-scale cross section. In this paper, we consider Majorana dark matter annihilating through a Higgs portal as a candidate source for this signal, where a large CP-violation in the Higgs coupling may serve to severely suppress scattering rates. In particular, we explore the phenomenology of two UV completions, a singlet-doublet model and a doublet-triplet model, and map out the available parameter space which can give a viable signal while respecting current experimental constraints.
Semi-classical BMS-blocks from the oscillator construction
Authors: Ammon Martin , Gray Seán , Moran Claire , Pannier Michel , Wölfl Katharina
Published: April 2021

Abstract

Flat-space holography requires a thorough understanding of BMS symmetry. We introduce an oscillator construction of the highest-weight representation of the$$ {\mathfrak{bms}}_3 $$bms3algebra and show that it is consistent with known results concerning the$$ {\mathfrak{bms}}_3 $$bms3module. We take advantage of this framework to prove that$$ {\mathfrak{bms}}_3 $$bms3-blocks exponentiate in the semi-classical limit, where one of the central charges is large. Within this context, we compute perturbatively heavy, and heavy-light vacuum$$ {\mathfrak{bms}}_3 $$bms3-blocks.
Reconstructing boosted Higgs jets from event image segmentation
Authors: Li Jinmian , Li Tianjun , Xu Fang-Zhou
Published: April 2021

Abstract

Based on the jet image approach, which treats the energy deposition in each calorimeter cell as the pixel intensity, the Convolutional neural network (CNN) method has been found to achieve a sizable improvement in jet tagging compared to the traditional jet substructure analysis. In this work, the Mask R-CNN framework is adopted to reconstruct Higgs jets in collider-like events, with the effects of pileup contamination taken into account. This automatic jet reconstruction method achieves higher efficiency of Higgs jet detection and higher accuracy of Higgs boson four-momentum reconstruction than traditional jet clustering and jet substructure tagging methods. Moreover, the Mask R-CNN trained on events containing a single Higgs jet is capable of detecting one or more Higgs jets in events of several different processes, without apparent degradation in reconstruction efficiency and accuracy. The outputs of the network also serve as new handles for the $$ t\overline{t} $$
t

t
¯

background suppression, complementing to traditional jet substructure variables.
Disentangling QCD and new physics in D → πℓ+ℓ−
Authors: Bharucha Aoife , Boito Diogo , Méaux Cédric
Published: April 2021

Abstract

In this paper we consider the decay D+ → π+ℓ+ℓ−, addressing in particular the resonance contributions as well as the relatively large contributions from the weak annihilation diagrams. For the weak annihilation diagrams we include known results from QCD factorisation at low q2 and at high q2, adapting the existing calculation for B decays in the Operator Product Expansion. The hadronic resonance contributions are obtained through a dispersion relation, modelling the spectral functions as towers of Regge-like resonances in each channel, as suggested by Shifman, imposing the partonic behaviour in the deep Euclidean. The parameters of the model are extracted using e+e− → (hadrons) and τ → (hadrons) + ντ data as well as the branching ratios for the resonant decays D+ → π+R(R → ℓ+ℓ−), with R = ρ, ω, and ϕ. We perform a thorough error analysis, and present our results for the Standard Model differential branching ratio as a function of q2. Focusing then on the observables FH and AFB, we consider the sensitivity of this channel to effects of physics beyond the Standard Model, both in a model independent way and for the case of leptoquarks.
A Weyl semimetal from AdS/CFT with flavour
Authors: Fadafan Kazem Bitaghsir , O’Bannon Andy , Rodgers Ronnie , Russell Matthew
Published: April 2021

Abstract

We construct a top-down holographic model of Weyl semimetal states using (3 + 1)-dimensional $$ \mathcal{N} $$
N
= 4 supersymmetric SU(Nc) Yang-Mills theory, at large Nc and strong coupling, coupled to a number Nf ≪ Nc of $$ \mathcal{N} $$
N
= 2 hypermultiplets with mass m. A U(1) subgroup of the R-symmetry acts on the hypermultiplet fermions as an axial symmetry. In the presence of a constant external axial gauge field in a spatial direction, b, we find the defining characteristic of a Weyl semi-metal: a quantum phase transition as m/b increases, from a topological state with non-zero anomalous Hall conductivity to a trivial insulator. The transition is first order. Remarkably, the anomalous Hall conductivity is independent of the hypermultiplet mass, taking the value dictated by the axial anomaly. At non-zero temperature the transition remains first order, and the anomalous Hall conductivity acquires non-trivial dependence on the hypermultiplet mass and temperature.
Searching for dark sectors in multi lepton final state in e+e− collisions
Authors: Ciafaloni Paolo , Martelli Gabriele , Raggi Mauro
Published: April 2021

Abstract

Electron positron collisions are a very promising environment to search for new physics, and in particular for dark sector related observables. The most challenging experimental problem in detecting dark sector candidates is the very high associated Standard Model background. For this reason it is important to identify observables that are, at the same time, minimally suppressed in the dark sector and highly suppressed in the Standard Model. One example is the e+e− → 3(e+e−) process that can be mediated either by the production and subsequent decay of dark Higgs (h′), e+e− → A′h′ → 6e [1] or produced by the Standards Model process e+e− → 3(e+e−). In the following letter we study the relative contribution to observed e+e− → 3(e+e−) total cross section, coming from the h′ mediated and from the Standard Model processes in the contest of fixed target and low energy collider experiments, with particular attention to the PADME experiment at the INFN Laboratori Nazionali di Frascati.
Holographic drag force in 5d Kerr-AdS black hole
Authors: Aref’eva Irina Ya. , Golubtsova Anastasia A. , Gourgoulhon Eric
Published: April 2021

Abstract

We consider the 5d Kerr-AdS black hole as a gravity dual to rotating quark-gluon plasma. In the holographic prescription we calculate the drag force acting on a heavy quark. According to the holographic approach a heavy quark can be considered through the string in the gravity dual. We study the dynamics of the string for the Kerr-AdS backgrounds with one non-zero rotational parameter and two non-zero rotational parameters that are equal in magnitude. For the case of one non-zero rotational parameter we find good agreement with the prediction from the 4d case considered by arXiv:1012.3800.
Aβ1-16 controls synaptic vesicle pools at excitatory synapses via cholinergic modulation of synapsin phosphorylation
Authors: Anni Daniela , Weiss Eva-Maria , Guhathakurta Debarpan , Akdas Yagiz Enes , Klueva Julia , Zeitler Stefanie , Andres-Alonso Maria , Huth Tobias , Fejtova Anna
Published: April 2021

Amyloid beta (Aβ) is linked to the pathology of Alzheimer’s disease (AD). At physiological concentrations, Aβ was proposed to enhance neuroplasticity and memory formation by increasing the neurotransmitter release from presynapse. However, the exact mechanisms underlying this presynaptic effect as well as specific contribution of endogenously occurring Aβ isoforms remain unclear. Here, we demonstrate that Aβ1-42 and Aβ1-16, but not Aβ17-42, increased size of the recycling pool of synaptic vesicles (SV). This presynaptic effect was driven by enhancement of endogenous cholinergic signalling via α7 nicotinic acetylcholine receptors, which led to activation of calcineurin, dephosphorylation of synapsin 1 and consequently resulted in reorganization of functional pools of SV increasing their availability for sustained neurotransmission. Our results identify synapsin 1 as a molecular target of Aβ and reveal an effect of physiological concentrations of Aβ on cholinergic modulation of glutamatergic neurotransmission. These findings provide new mechanistic insights in cholinergic dysfunction observed in AD.
An Eigensystem Approach to Anderson Localization for Multi-particle Systems
Authors: Bringmann Bjoern , Mendelson Dana
Published: April 2021

This paper revisits the proof of Anderson localization for multi-particle systems. We introduce a multi-particle version of the eigensystem multi-scale analysis by Elgart and Klein, which had previously been used for single-particle systems.
High-cycle fatigue behaviour of a timber-to-timber connection with self-tapping screws under lateral loading
Authors: Niebuhr Peter , Sieder Mike
Published: April 2021

The high-cycle fatigue behaviour of a timber-to-timber connection with self-tapping screws is examined with the fasteners under bending due to their alignment lateral to the load direction. The cyclic tests were carried out with a sinusoidal non-reversed load ($$R=0.1$$

R
=
0.1

) with a loading frequency of 5 Hz. The examined connection is designed for the quasistatic failure mechanism with two plastic hinges per shear plane according to Johansen’s theory (European Yield Model), which is mirrored in the observed fatigue failure. Based on 30 cyclic tests on four nominal stress levels $$\left( S=\left\{ 0.47,\;0.41,\;0.31,\;0.20 \right\} \right) $$

S
=

0.47
,

0.41
,

0.31
,

0.20

in the finite-life regime the respective Wöhler-curve is obtained, showing high conformity with the test data due to a consideration of the specific density of the individual specimens. It is shown that the examined fasteners show a superior fatigue behaviour under bending compared to axial loading. A simple safe-side approach for the application of Wöhler-curves for axial loading of threaded fasteners to the present case of fastener bending is proposed, extending the field of possible applications for the results of existing and future studies of the behaviour under axial loading.
Social stress and risk of declining cognition: a longitudinal study of men and women in the United States
Authors: Lindert Jutta , Paul Kimberley C. , Lachman Margie E. , Ritz Beate , Seeman Teresa
Published: April 2021

Limited research is available on the relationship between social stress and risk of declining cognition. We sought to examine whether social stress has adverse effects on risk of declining episodic memory and executive functioning in aging individuals. We used data from the MIDUS study, a national probability sample of non-institutionalized, English speaking respondents aged 25–74 living in the 48 contiguous states of the United States. The initial wave (1995) included 4963 non-institutionalized adults aged 32–84 (M = 55, SD = 12.4). We used an analytic sample from MIDUS-II (1996/1997) and MIDUS-III (2013) (n = 1821). The dependent variables are episodic memory and executive functioning, which were assessed with the Brief Test for Cognition (BTACT). The independent variables were social stress variables (subjective social status, family and marital stress, work stress and discrimination). To evaluate episodic memory and executive functioning changes over a time period of 10 years, we estimated adjusted linear regression models. Women report significantly lower subjective social status and more discrimination stress than men across all age groups. Controlling for education and income, age, and baseline episodic memory and executive functioning, lower subjective social status had additional adverse effects on declines in episodic memory in men and women. Marital risk had adverse effects on episodic memory in men but not in women. Daily discrimination had adverse effects on executive functioning on all individuals. Public health strategies should focus on reducing social stress in a socio-ecological perspective. Especially, subjective social status and discrimination stress might be a target for prevention efforts.
An ultrasound observation study on the levator hiatus with or without diastasis recti abdominis in postpartum women
Authors: Tian Peng , Liu Dong Mei , Wang Chao , Gu Yu , Du Guo Qing , Tian Jia Wei
Published: April 2021

Introduction and hypothesis

We hypothesized that differences in post-partum levator hiatus (LH) measurements, as well as the area of urethra and bladder (AUB), viewed under ultrasound, correlate with diastasis rectus abdominis (DRA) occurrence. The primary objective of this study is to determine ultrasound parameters available for diagnosing DRA in post-partum women. We compared LH and AUB measurements under ultrasound in primiparous women, with and without DRA, at 24–26 weeks postpartum.

Methods

One hundred ninety-four women underwent routine examination, including a self-made clinical symptoms questionnaire, DRA evaluation, and LH and AUB measurements. Independent samples t- and chi-squared tests were used to compare the differences between women with and without DRA.

Results

DRA incidence was significantly higher among those who underwent cesarean section (CS) than for vaginal delivery (VD) (P = 0.038). DRA patients could potentially have urinary urgency, frequency, pain, dysuria, and perineal tears. Additionally, statistically significant differences were found between VD patients, with or without DRA, in the resting LH transverse diameter (TrD) (P = 0.032) and the area of the levator hiatus (ALH) (P = 0.048) as well as AUB at Valsalva (P = 0.049). No differences, however, were found between the DRA and no DRA groups for all those measurements among women who had cesarean deliveries.

Conclusions

DRA was more likely in post-CS women. Furthermore, the results showed a plausible association between DRA occurrence and LH expansion, especially in women with VD under rest and Valsalva. This could be useful for developing therapeutic plans based on these parameters for post-partum rehabilitation of women with DRA to avoid long-term complications.
Correction to: The pathophysiology of stress urinary incontinence: a systematic review and meta-analysis
Authors: Falah-Hassani Kobra , Reeves Joanna , Shiri Rahman , Hickling Duane , McLean Linda
Published: April 2021

A correction to this paper has been published: 10.1007/s00192-021-04794-y