bluuebunny/crossref_metadata_2025 huggingface dataset:
The Total Synthesis of Diquinane‐Containing Natural Products
Authors: Li Huilin , Zhang Jing , She Xuegong
Published: September 2020

Diquinane or bicyclo[3.3.0]octane is a conspicuous structural unit existing in the carbo‐frameworks of a wide range of natural products such as alkaloids and terpenoids. These diquinane‐containing molecules not merely exhibit intriguing architectures, but also showcase a broad spectrum of significant bioactivities, which draw widespread attention from the global synthetic community. During the past decade, with an aim to accomplish the total syntheses of such specified cornucopias of natural products, a variety of elegant strategies for construction of the diquinane ring system have been disclosed. In this Minireview, the achievements on this subject in the timeline from 2010 to June 2020 are demonstrated and it is discussed how the diquinane unit is strategically forged in the context of the specific target structure. In addition, impacts of the selected works to the field of natural product total synthesis is highlighted and the particular outlook of diquinane‐containing natural product synthesis is provided.
Antivitamins B12—Some Inaugural Milestones
Authors: Kräutler Bernhard
Published: September 2020

The recently delineated structure‐ and reactivity‐based concept of antivitamins B12 has begun to bear fruit by the generation, and study, of a range of such B12‐dummies, either vitamin B12‐derived, or transition metal analogues that also represent potential antivitamins B12 or specific B12‐antimetabolites. As reviewed here, this has opened up new research avenues in organometallic B12‐chemistry and bioinorganic coordination chemistry. Exploratory studies with antivitamins B12 have, furthermore, revealed some of their potential, as pharmacologically interesting compounds, for inducing B12‐deficiency in a range of organisms, from hospital resistant bacteria to laboratory mice. The derived capacity of antivitamins B12 to induce functional B12‐deficiency in mammalian cells and organs also suggest their valuable potential as growth inhibitors of cancerous human and animal cells.
Comparison of Penta and Tetra‐pyridyl Cobalt‐based Catalysts for Water Reduction: H2 Production Cycle, Solvent Response and Reduction Free Energy
Authors: Gurdal Yeliz , Iannuzzi Marcella
Published: September 2020

Understanding water reduction towards H2 generation is crucial to overcome today's renewable energy obstacles. Previous studies have shown the superior H2 production performances of Cobalt based penta‐pyridyl (CoaPPy) and tetra‐pyridyl (CoaTPy) complexes in solution. We investigate H2 production cycles of CoaPPy and CoaTPy complexes immersed in water solution by means of Ab‐initio Molecular Dynamics and Density Functional Theory. We monitor dynamic properties of the systems, solvent response and structural changes occurring in the catalysts, by simulating all intermediate steps of the H2 production cycle. Reduction free energies and reorganization energies are calculated. Our results show that, following the first electron injection, H2 production proceeds with the singlet spin state. Following the first electron insertion, we observe a significant rearrangement of the hydrogen bonding network in the first solvation shell. The cobalt center turns out to be more accessible for the surrounding water molecules in the case of CoaTPy at all the intermediate steps, which explains its higher catalytic performance over CoaPPy. Following the first reduction reaction, a larger gain in reduction free energy is estimated for CoaTPy with respect to CoaPPy, with a difference of 0.14 eV, in line with the experiments. For the second reduction, instead, CoaPPy shows more negative reduction potential, by 0.41 eV.
Metastatic low‐grade endometrial stromal sarcoma after 24 years: A case report and review of recent molecular genetics
Authors: Mindiola‐Romero Andres E. , Liu Xiaoying , Dillon Jessica L. , Talarico Michael , Smith Geoffrey , Zhang Linsheng , Linos Konstantinos
Published: September 2020

Low‐grade endometrial stromal sarcoma (LGESS) is a rare malignant uterine tumor with the potential to metastasize years after the primary resection. There is a broad differential diagnosis for endometrial stromal sarcomas (ESS), including both benign and malignant entities. Herein, we present the case of a 64‐year‐old female with metastatic LGESS to the lung, diagnosed by cytology, 24 years after her initial presentation. This report discusses the cytomorphologic and histopathologic characteristics, and ancillary studies including immunohistochemical stains and recent advances in molecular diagnostics of ESS. Accurate diagnosis of spindle cell lesions in the lung can be challenging. As such, this case highlights the instrumental role of ancillary testing and molecular diagnostics to achieve a more definitive diagnosis.
Immunity in salamander regeneration: Where are we standing and where are we headed?
Authors: Bolaños‐Castro Lizbeth Airais , Walters Hannah Elisabeth , García Vázquez Rubén Octavio , Yun Maximina Hee
Published: September 2020

Salamanders exhibit the most extensive regenerative repertoire among vertebrates, being able to accomplish scar‐free healing and faithful regeneration of significant parts of the eye, heart, brain, spinal cord, jaws and gills, as well as entire appendages throughout life. The cellular and molecular mechanisms underlying salamander regeneration are currently under extensive examination, with the hope of identifying the key drivers in each context, understanding interspecies differences in regenerative capacity, and harnessing this knowledge in therapeutic settings. The immune system has recently emerged as a potentially critical player in regenerative responses. Components of both innate and adaptive immunity have been found at critical stages of regeneration in a range of salamander tissues. Moreover, functional studies have identified a requirement for macrophages during heart and limb regeneration. However, our knowledge of salamander immunity remains scarce, and a thorough definition of the precise roles played by its members is lacking. Here, we examine the evidence supporting roles for immunity in various salamander regeneration models. We pinpoint observations that need revisiting through modern genetic approaches, uncover knowledge gaps, and highlight insights from various model organisms that could guide future explorations toward an understanding of the functions of immunity in regeneration.
Foraging in a dynamic environment: Response of four sympatric sub‐Antarctic albatross species to interannual environmental variability
Authors: Carpenter‐Kling Tegan , Reisinger Ryan R. , Orgeret Florian , Connan Maëlle , Stevens Kim L. , Ryan Peter G. , Makhado Azwianewi , Pistorius Pierre A.
Published: September 2020

Seasonal and annual climate variations are linked to fluctuations in the abundance and distribution of resources, posing a significant challenge to animals that need to adjust their foraging behavior accordingly. Particularly during adverse conditions, and while energetically constrained when breeding, animals ideally need to be flexible in their foraging behavior. Such behavioral plasticity may separate “winners” from “losers” in light of rapid environmental changes due to climate change. Here, the foraging behavior of four sub‐Antarctic albatross species was investigated from 2015/16 to 2017/18, a period characterized by pronounced environmental variability. Over three breeding seasons on Marion Island, Prince Edward Archipelago, incubating wandering (WA,Diomedea exulans;n = 45), grey‐headed (GHA,Thalassarche chrysostoma;n = 26), sooty (SA,Phoebetria fusca;n = 23), and light‐mantled (LMSA,P. palpebrata;n = 22) albatrosses were tracked with GPS loggers. The response of birds to environmental variability was investigated by quantifying interannual changes in their foraging behavior along two axes: spatial distribution, using kernel density analysis, and foraging habitat preference, using generalized additive mixed models and Bayesian mixed models. All four species were shown to respond behaviorally to environmental variability, but with substantial differences in their foraging strategies. WA was most general in its habitat use defined by sea surface height, eddy kinetic energy, wind speed, ocean floor slope, and sea‐level anomaly, with individuals foraging in a range of habitats. In contrast, the three smaller albatrosses exploited two main foraging habitats, with habitat use varying between years. Generalist habitat use by WA and interannually variable use of habitats by GHA, SA, and LMSA would likely offer these species some resilience to predicted changes in climate such as warming seas and strengthening of westerly winds. However, future investigations need to consider other life‐history stages coupled with demographic studies, to better understand the link between behavioral plasticity and population responses.
How to design optimal eDNA sampling strategies for biomonitoring in river networks
Authors: Carraro Luca , Stauffer Julian B. , Altermatt Florian
Published: September 2020

Abstract

The current biodiversity crisis calls for appropriate methods for assessing biodiversity. In this respect, environmental DNA (eDNA) holds great promise, especially for aquatic ecosystems. While initial eDNA studies assessed biodiversity at single sites, technology now allows analyzing samples from many points simultaneously. However, the selection of these sites has been mostly motivated on an ad‐hoc basis. To this end, hydrology‐based models might offer a unique guidance on where to sample eDNA to most effectively reconstruct spatial patterns of biodiversity. Here, we performed computer simulations to identify best‐practice criteria for the choice of positioning of eDNA sampling sites in river networks. To do so, we combined a hydrology‐based eDNA transport model with a virtual river network reproducing the scaling features of real rivers. In particular, we conducted simulations investigating scenarios of different number and location of eDNA sampling sites in a riverine network, different spatial taxon distributions, and different eDNA measurement errors. We found that, due to hydrological controls, non‐uniform patterns of eDNA concentration arise even if the taxon distribution is uniform and decay is neglected. Best practices for sampling site selection depend on the taxon's spatial distribution: when taxa are concentrated in some hotspots and only few sampling sites can be placed, it is better to preferentially locate them in the downstream part of the catchment; when taxa are more evenly distributed, and/or many sites can be placed, these should be preferentially located upstream. We also found that uncertainties in eDNA concentration estimates do not necessarily hamper model predictions. Knowledge of eDNA decay rates improves model predictions, highlighting the need for empirical estimates of these rates under relevant environmental conditions. Our simulations help define strategies for designing eDNA sampling campaigns in river networks and can guide the sampling effort of field ecologists and environmental authorities.
Fatal lymphocytic cardiac damage in coronavirus disease 2019 (COVID‐19): autopsy reveals a ferroptosis signature
Authors: Jacobs Werner , Lammens Martin , Kerckhofs Annelies , Voets Evy , Van San Emily , Van Coillie Samya , Peleman Cédric , Mergeay Matthias , Sirimsi Sabriya , Matheeussen Veerle , Jansens Hilde , Baar Ingrid , Vanden Berghe Tom , Jorens Philippe G.
Published: September 2020

Aims

Cardiovascular complications, including myocarditis, are observed in coronavirus disease 2019 (COVID‐19). Major cardiac involvement is a potentially lethal feature in severe cases. We sought to describe the underlying pathophysiological mechanism in COVID‐19 lethal cardiogenic shock.

Methods and results

We report on a 48‐year‐old male COVID‐19 patient with cardiogenic shock; despite extracorporeal life support, dialysis, and massive pharmacological support, this rescue therapy was not successful. Severe acute respiratory syndrome coronavirus 2 RNA was detected at autopsy in the lungs and myocardium. Histopathological examination revealed diffuse alveolar damage, proliferation of type II pneumocytes, lymphocytes in the lung interstitium, and pulmonary microemboli. Moreover, patchy muscular, sometimes perivascular, interstitial mononuclear inflammatory infiltrates, dominated by lymphocytes, were seen in the cardiac tissue. The lymphocytes ‘interlocked’ the myocytes, resulting in myocyte degeneration and necrosis. Predominantly, T‐cell lymphocytes with a CD4:CD8 ratio of 1.7 infiltrated the interstitial myocardium, reflecting true myocarditis. The myocardial tissue was examined for markers of ferroptosis, an iron‐catalysed form of regulated cell death that occurs through excessive peroxidation of polyunsaturated fatty acids. Immunohistochemical staining with E06, a monoclonal antibody binding to oxidized phosphatidylcholine (reflecting lipid peroxidation during ferroptosis), was positive in morphologically degenerating and necrotic cardiomyocytes adjacent to the infiltrate of lymphocytes, near arteries, in the epicardium and myocardium. A similar ferroptosis signature was present in the myocardium of a COVID‐19 subject without myocarditis. In a case of sudden death due to viral myocarditis of unknown aetiology, however, immunohistochemical staining with E06 was negative. The renal proximal tubuli stained positively for E06 and also hydroxynonenal (4‐HNE), a reactive breakdown product of the lipid peroxides that execute ferroptosis. In the case of myocarditis of other aetiology, the renal tissue displayed no positivity for E06 or 4‐HNE.

Conclusions

The findings in this case are unique as this is the first report on accumulated oxidized phospholipids (or their breakdown products) in myocardial and renal tissue in COVID‐19. This highlights ferroptosis, proposed to detrimentally contribute to some forms of ischaemia–reperfusion injury, as a detrimental factor in COVID‐19 cardiac damage and multiple organ failure.
An Electrochemical ATP Biosensor with Enzymes Entrapped within a PEDOT Film
Authors: Peteu Serban F. , Russell Skye A. , Galligan James J. , Swain Greg M.
Published: September 2020

This paper reports on the electrochemical behavior of an ATP biosensor that utilizes glucose oxidase (GOx) and hexokinase (Hex) immobilized within the electroactive polymer, polyethylenedioxythiophene (PEDOT). This biosensor design detects ATP indirectly at 0.85 V vs. Ag/AgCl based on the oxidation current for enzymatically generated H2O2, and at −0.20 V; a potential at which improved analyte selectivity is achieved. The detection figures of merit at both detection potentials are a response time of 15±1 s, an experimental detection limit of 10.0±0.2 μmol L−1 (S/N=3), and a sensitivity in the range of 100–500 mA M−1cm−2.
Kinetic characteristics of long‐term repeated fed‐batch (LtRFb) l‐lactic acid fermentation by a Bacillus coagulans strain
Authors: Zhang Fan , Liu Jiongqin , Han Xiao , Gao Chao , Ma Cuiqing , Tao Fei , Xu Ping
Published: September 2020

Application of degradable plastics is the most critical solution to plastic pollution. As the precursor of biodegradable plastic PLA (polylactic acid), efficient production of l‐lactic acid is vital for the commercial replacement of traditional plastics. Bacillus coagulans H‐2, a robust strain, was investigated for effective production of l‐lactic acid using long‐term repeated fed‐batch (LtRFb) fermentation. Kinetic characteristics of l‐lactic acid fermentation were analyzed by two models, showing that cell‐growth coupled production gradually replaces cell‐maintenance coupled production during fermentation. With the LtRFb strategy, l‐lactic acid was produced at a high final concentration of 192.7 g/L, on average, and a yield of up to 93.0% during 20 batches of repeated fermentation within 487.5 h. Thus, strain H‐2 can be used in the industrial production of l‐lactic acid with optimization based on kinetic modeling.
Optimal Sizing and Assessment of an Islanded Photovoltaic‐Battery‐Diesel Generator Microgrid Applicable to a Remote School of Bangladesh
Authors: Ishraque Md. Fatin , Shezan Sk. A. , Nur Jannati Nabiha , Islam Md. Shafiul
Published: September 2020

Electricity has become a part and parcel of modern life. The world is constantly developing, and the electricity demand is inevitably increasing with it. It is a big challenge for the power generation organizations to cope up with this increasing demand. For a developing country like Bangladesh, this challenge is even bigger. Bangladesh has many remote areas which are deprived of grid connectivity. In this article, system design and performance evaluation are conducted on a solar battery‐based hybrid renewable energy system (HRES) with diesel backup for a school in a remote area located in the northern part of the country, where conventional power grid connectivity is not available. From field survey, a load demand of 10.468 kWh/day for a normal working day and a peak demand of 3.3 kW are considered in this work for the proposed site. For simulation purpose hybrid optimization model for electric renewable, very well‐known software is used. The solar radiation data required for the work are collected from NASA Surface meteorology and Solar Energy database. Analyzing the load requirements and metrological data a solar‐battery diesel generator‐based HRES is proposed for the school. From the analysis and simulation, the Net Present Cost (NPC) for the proposed system is found USD 6191 with a Cost of Energy (COE) of $0.125/kWh. Further, a comparative study is done and the proposed system can reduce the COE and Green House Gas (GHG) emission of about 29.85% and 69% respectively than the conventional power plants. Finally, a techno‐economic analysis is conducted with sensitivity analysis, time series analysis, and multiyear analysis to prove the rigidity of the proposed system.
An Intelligent Deformation‐Based Approach to the State of Health Estimation of Collided Lithium‐Ion Batteries for Facilitating Battery Module Safety Evaluation
Authors: Zhang Jian , Liu Xiangyang , Chen Chunrong , Simeone Alessandro
Published: September 2020

With the increasing trend of electric vehicles sales, the awareness for safety issues in energy storage systems has seen a rapid growth. In this context, literature predominantly focuses on the assessment of lithium‐ion battery cell State of Health (SoH) under regular operating conditions. An interesting gap is highlighted by scarce contributions with reference to the SoH in case of collision impacts. This paper proposes a method for estimating the battery cell SoH from collision deformation features via finite element (FE) simulation. An experimental series of collision impact tests is performed on battery cells to study deformation features. A 3D scanning procedure is performed on the cells to retrieve the geometrical features. The cells damage evaluation is carried out by considering physical and electrical performances. The SoH classification is modeled as a machine learning–based pattern recognition enabled by Artificial Neural Network (ANN) trained with deformation features and classifying cells into safe, latent danger, and unsafe cells respectively. Utilizing such pattern classifier, a FE approach is used to conduct an impact simulation on a battery module. In this respect, the deformation features obtained via simulation are input into the ANN pattern classifier experimentally trained to predict the cells SoH within the module.
Optimization of arrayed waveguide grating‐filtering response for efficient analog radio‐over‐fiber fronthaul over a wavelength‐division multiplexing passive optical network
Authors: Plazas Caio L. M. P. , de Souza Adelcio M. , Celino Daniel R. , Romero Murilo A.
Published: September 2020

Wavelength‐division multiplexing passive optical network (WDM‐PON) is a promising solution to cope with the exponential data traffic growth, particularly regarding future mobile fronthaul. WDM‐PON schemes, based on self‐seeded wavelength agnostic transmitters using reflective semiconductor optical amplifiers (RSOAs), are seen as an option to provide an analog radio‐over‐fiber (A‐RoF) alternative to the current digital fronthaul. Although these A‐RoF have been already successfully demonstrated, it was observed that the arrayed waveguide grating (AWG)‐filtering characteristics affect both the optical seed generation and the radio signal integrity, requiring a design optimization. In order to do so, in this article, we optimize the A‐RoF transmission performance by comparing Bessel, Gaussian, and flat‐top AWG‐filter formats. The impact of seed linewidth and red‐shift on the signal error‐vector magnitude (EVM) and phase rotation is also investigated. We have found that EVM performance for BPSK and 16QAM transmission provided an improvement of 45% when compared to our previous results, with a phase offset of 0.8°, indicating little to no distortion, as a result of the selection of the optimal AWG filtering response.
Putting ethnographic flesh on new materialist bones: Lyme disease and the sex/gender binary
Authors: Dumes Abigail A.
Published: September 2020

In the United States, there is heated debate over the biological reality of chronic Lyme disease (the persistence of Lyme disease beyond standard antibiotic treatment). Like other bodily conditions whose biological basis is disputed, chronic Lyme disease is perceived to be more common among women, a phenomenon for which physicians and patients often provide gender‐based explanations. However, influenced by the field of sex‐based biology, Lyme disease patients and their physicians are increasingly navigating how and whether to make claims to biological legitimacy through the science of sex‐based differences. Drawing on ethnographic research among Lyme disease patients, physicians, and scientists throughout the northeastern United States, I explore the mutually reinforcing relationship between feminist scholarship on the sex/gender binary and emerging ideas about sex and gender in the context of health.
Impact of increasing concentration of tart and sweet cherries juices concentrates on healthy mice gut microbiota
Authors: Al Othaim Ayoub , Marasini Daya , Carbonero Franck
Published: September 2020

Cherries are an excellent source of dietary polyphenols and are marketed as sports and health dietary supplements. However, there are still limited direct evidence for their purported nutritional and health benefits. Gut microbiota modulation ought to be tested because most polyphenols reach the colon where they undergo microbial metabolization to bioactive and bioavailable metabolites. In the present study, varying dilutions of three concentrate cherries juices, Montmorency tart cherry juice, Balaton tart cherry juice, and sweet cherry juice, were examined to determine their potential effect on the murine gut microbiota composition. Forty‐five mice were randomly assigned to three different groups. Each group received an increased concentration of its assigned juices (1/20, 1/15, 1/10, 1/7, and 1/4 [v/v]) every 5 days for 25 days. Fecal samples were collected after each concentration change for microbiota characterization by high‐throughput 16S rRNA gene sequencing using Illumina Miseq. The results revealed consistent gut microbiota modulation based on concentration regardless of the juice type, but not in a true dose‐dependent manner. The two median concentrations and the two highest were significantly different from each other and from the baseline and lowest concentration. Increasing cherries consumption consistently resulted in significant increase of the relative abundance of Barnesiella and Akkermansia, whereas Bacteroides abundance was negatively correlated with the concentration of the juice. Overall, we demonstrate that cherries induce a beneficial modulation of the murine gut microbiota, and that amounts of fruits consumed need to be considered to devise appropriate health and nutrition studies.
Astrocytes are necessary for blood–brain barrier maintenance in the adult mouse brain
Authors: Heithoff Benjamin P. , George Kijana K. , Phares Aubrey N. , Zuidhoek Ivan A. , Munoz‐Ballester Carmen , Robel Stefanie
Published: September 2020

In the adult brain, multiple cell types are known to produce factors that regulate blood–brain barrier (BBB) properties, including astrocytes. Yet several recent studies disputed a role for mature astrocytes at the BBB. To determine if astrocytes contribute a nonredundant and necessary function in maintaining the adult BBB, we used a mouse model of tamoxifen‐inducible astrocyte ablation. In adult mice, tamoxifen induction caused sparse apoptotic astrocyte cell death within 2 hr. Indicative of BBB damage, leakage of the small molecule Cadaverine, and the large plasma protein fibrinogen into the brain parenchyma indicative of BBB damage was detected as early as astrocyte ablation was present. Vessels within and close to regions of astrocyte loss had lower expression of the tight junction protein zonula occludens‐1 while endothelial glucose transporter 1 expression was undisturbed. Cadaverine leakage persisted for several weeks suggesting a lack of barrier repair. This is consistent with the finding that ablated astrocytes were not replaced. Adjacent astrocytes responded with partial nonproliferative astrogliosis, characterized by morphological changes and delayed phosphorylation of STAT3, which restricted dye leakage to the brain and vessel surface areas lacking coverage by astrocytes 1 month after ablation. In conclusion, astrocytes are necessary to maintain BBB integrity in the adult brain. BBB‐regulating factors secreted by other cell types, such as pericytes, are not sufficient to compensate for astrocyte loss.
Overdiagnosis in lung cancer screening: Estimates from the German Lung Cancer Screening Intervention Trial
Authors: González Maldonado Sandra , Motsch Erna , Trotter Anke , Kauczor Hans‐Ulrich , Heussel Claus‐Peter , Hermann Silke , Zeissig Sylke Ruth , Delorme Stefan , Kaaks Rudolf
Published: September 2020

Overdiagnosis is a major potential harm of lung cancer screening; knowing its potential magnitude helps to optimize screening eligibility criteria. The German Lung Screening Intervention Trial (“LUSI”) is a randomized trial among 4052 long‐term smokers (2622 men), 50.3 to 71.9 years of age from the general population around Heidelberg, Germany, comparing five annual rounds of low‐dose computed tomography (n = 2029) with a control arm without intervention (n = 2023). After a median follow‐up of 9.77 years postrandomization and 5.73 years since last screening, 74 participants were diagnosed with lung cancer in the control arm and 90 in the screening arm: 69 during the active screening period; of which 63 screen‐detected and 6 interval cancers. The excess cumulative incidence in the screening arm (N = 16) represented 25.4% (95% confidence interval: −11.3, 64.3] of screen‐detected cancer cases (N = 63). Analyzed by histologic subtype, excess incidence in the screening arm appeared largely driven by adenocarcinomas. Statistical modeling yielded an estimated mean preclinical sojourn time (MPST) of 5.38 (4.76, 5.88) years and a screen‐test sensitivity of 81.6 (74.4%, 88.8%) for lung cancer overall, all histologic subtypes combined. Based on modeling, we further estimated that about 48% (47.5% [43.2%, 50.7%]) of screen‐detected tumors have a lead time ≥4 years, whereas about 33% (32.8% [28.4%, 36.1%]) have a lead time ≥6 years, 23% (22.6% [18.6%, 25.7%]) ≥8 years, 16% (15.6% [12.2%, 18.3%]) ≥10 years and 11% (10.7% [8.0%, 13.0%]) ≥12 years. The high proportions of tumors with relatively long lead times suggest a major risk of overdiagnosis for individuals with comparatively short remaining life expectancies.
The role of reproductive coercion in women’s risk for HIV: A case‐control study of outpatients in Gauteng, South Africa
Authors: McCloskey Laura Ann , Hitchcock Sonia , Eloff Irma , Dinh Paul , Masemola Khomotso
Published: September 2020

Objectives

To investigate how reproductive coercion, or men’s attempts to control their partners’ use of contraception, may contribute to adverse reproductive health outcomes for women including abortions, sexually transmitted infections, and HIV for young women in South Africa.

Methods

Findings are based on a case‐control interview study of 882 South African women outpatients aged 15–29 years, 48.5% (n=427) of whom were HIV seropositive. Covariates include demographics, intimate partner violence, sexually transmitted infections, having an abortion, using long‐acting reversible contraception, and unequal sexual relationship power.

Results

Most covariates with the exceptions of abortion and unequal relationship power increase the risk of HIV, and all relate to reproductive coercion. Intimate partner violence is strongly associated with reproductive coercion (odds ratio 3.86, 95% confidence interval 2.89–5.15). When intimate partner violence is included in the full model reproductive coercion remains a significant predictor of HIV by 42%, and acts as a partial mediator between IPV and HIV.

Conclusion

Findings confirm the significance of reproductive coercion as a risk marker for HIV. Reproductive coercion undermines women’s reproductive health and warrants clinical intervention. Recommendations are offered for clinical practice within the South African context to increase training and assessment and provide covert long‐acting reversible contraception as one pathway towards promoting women’s reproductive autonomy.
Assessing four different macroscopic water uptake models for maize plant (ZEA mays L.) under salinity stress*
Authors: Jalali Vahidreza , Asadi Kapourchal Safoora
Published: September 2020

The global shortage of fresh water in arid/semi‐arid regions has inevitably led to the use of unconventional sources of water. One of the strategies for managing saline water consumption is by using simulator models that can help in understanding the physiological response of crops. In this study the number of germinated seeds, shoot fresh weight and plant leaf area index as three of the main parameters of the vegetative stage of maize plants were investigated. In order to quantify the effect of different salinities on vegetative growth parameters, the macroscopic models of Homaee et al., Dirksen et al., van Genuchten and Hoffman and Maas and Hoffman were tested. The fitting of different models to measured data of germinated seeds showed that the Maas and Hoffman model was superior over the other three models with r and NSE values of 0.87 and 0.79, respectively. Similarly, the model of Homaee et al. with the values of r = 0.98 and NSE = 0.89 was the best model for the maize fresh weight variable. Finally, for the leaf area index variable, the van Genuchten and Hoffman model having values of r = 0.95 and NSE = 0.91 was able to provide a better estimate than the other models.
Characterization of bonding modes in metal complexes through electron density cross‐sections
Authors: de Beer Shane , Cukrowski Ignacy , de Lange Jurgens H.
Published: September 2020

Qualitative inspection of molecular orbitals (MOs) remains one of the most popular analysis tools used to describe the electronic structure and bonding properties of transition metal complexes. In symmetric coordination complexes, the use of group theory and the symmetry‐adapted linear combination (SALC) of fragment orbitals allows for a very accurate and informative interpretation of MOs, but the same procedure cannot be performed for asymmetric complexes, such as Schrock and Fischer carbenes. In this work, we present a straight‐forward approach for classifying and quantifying MO contributions to a particular metal–ligand interaction. Our approach utilizes the topology of MO density contributions to a cross‐section of an inter‐nuclear region, and is computationally inexpensive and applicable to symmetric and asymmetric complexes alike. We also apply the same approach with similar decompositions using Natural Bond Orbitals (NBO) and the recently developed Fragment, Atomic, Localized, Delocalized and Interatomic (FALDI) density decomposition scheme. In particular, FALDI analysis provides additional insights regarding the multi‐centric nature of metal‐carbene bonds without resorting to expensive multi‐reference calculations.
2‐Oxothiazolidine‐4‐carboxylic acid inhibits vascular calcification via induction of glutathione synthesis
Authors: Patel Jessal J. , Bourne Lucie E. , Thakur Shori , Farrington Ken , Gorog Diana A. , Orriss Isabel R. , Baydoun Anwar R.
Published: September 2020

Arterial medial calcification (AMC), the deposition of hydroxyapatite in the medial layer of the arteries, is a known risk factor for cardiovascular events. Oxidative stress is a known inducer of AMC and endogenous antioxidants, such as glutathione (GSH), may prevent calcification. GSH synthesis, however, can be limited by cysteine levels. Therefore, we assessed the effects of the cysteine prodrug 2‐oxothiazolidine‐4‐carboxylic acid (OTC), on vascular smooth muscle cell (VSMC) calcification to ascertain its therapeutic potential. Human aortic VSMCs were cultured in basal or mineralising medium (1 mM calcium chloride/sodium phosphate) and treated with OTC (1–5 mM) for 7 days. Cell‐based assays and western blot analysis were performed to assess cell differentiation and function. OTC inhibited calcification ≤90%, which was associated with increased ectonucleotide pyrophosphatase/phosphodiesterase activity, and reduced apoptosis. In calcifying cells, OTC downregulated protein expression of osteoblast markers (Runt‐related transcription factor 2 and osteopontin), while maintaining expression of VSMC markers (smooth muscle protein 22α and α‐smooth muscle actin). GSH levels were significantly reduced by 90% in VSMCs cultured in calcifying conditions, which was associated with declines in expression of gamma‐glutamylcysteine synthetase and GSH synthetase. Treatment of calcifying cells with OTC blocked the reduction in expression of both enzymes and prevented the decline in GSH. This study shows OTC to be a potent and effective inhibitor of in vitro VSMC calcification. It appears to maintain GSH synthesis which may, in turn, prevent apoptosis and VSMCs gaining osteoblast‐like characteristics. These findings may be of clinical relevance and raise the possibility that treatment with OTC could benefit patients susceptible to AMC.
Apert syndrome: A case report of prenatal ultrasound, postmortem cranial CT, and molecular genetic analysis
Authors: Zhang Weixia , Xue Hongyuan , Huang Dai , Ye Yuquan , Chen Xiao
Published: September 2020

Apert syndrome is characterized by craniosynostosis, mid‐facial hypoplasia, and symmetric syndactyly. Prenatal diagnosis is challenging until the skull and facial anomalies become more pronounced during the third trimester. We present a case in which typical sonographic signs of Apert syndrome were observed after 23 weeks of gestation. Following termination of the pregnancy, both clinical features such as craniofacial abnormalities and syndactyly and cranial 3D‐CT images showed high correlation with the previous sonographic findings. Furthermore, genetic analysis revealed a spontaneous mutation, c.755C≥G (p.S252W), in the FGFR2 gene, with this mutation implicated in the etiology of Apert syndrome.
A nationwide survey of online teaching strategies in dental education in China
Authors: Wang Kun , Zhang Linglin , Ye Ling
Published: September 2020

Objectives

Due to the time and cost effectiveness, online teaching has played a significant role in the provision of education and has been a well‐accepted strategy for higher education in the world. The aim of this study was to survey the current online undergraduate education status in dental medicine in mainland China during the critical stage of the COVID‐19 outbreak, as well to provide a better understanding of practicing this learning strategy for the improvement and development of dental education.

Methods

For the cross‐sectional survey, recruitment emails regarding to the implementation of online education were sent to 42 dental colleges and universities in mainland China between March and April 2020.

Results

Ninety‐seven percent of the respondents have opened online courses during COVID‐19 pandemic in China, 74% of which chose live broadcast as the major teaching way. As compared with theoretical courses, fewer specialized practical curriculums were set up online with a lower satisfaction from students in most dental schools. For the general evaluation of online learning from students of different dental schools, the “online learning content” received the highest support, while the “interaction between teachers and students” showed the lowest satisfaction. Most schools reported that the difficulty in assurance of students’ learning motivation was the main problem in online education.

Conclusions

Our findings indicate the necessity and efficacy of the overall online teaching for dental education during the epidemic that can be further improved with the education model and pedagogical means to boost the informationization of dental education for future reference.
Marginal adaptation and fracture strength of endocrowns manufactured with different restorative materials: SEM and mechanical evaluation
Authors: Sağlam Gaye , Cengiz Seda , Karacaer Özgül
Published: September 2020

Endocrowns were manufactured using different restorative materials to evaluate the marginal adaptation and fracture strength. Fifty endodontically treated mandibular first molar teeth were divided into five groups (n = 10). Endocrowns were obtained from lithium disilicate glass ceramic ingots by heat‐press technique (Group e.max Press: GEP), and from feldspathic blocks (Group Cerec: GC), polymer infiltrated ceramic network blocks (Group Enamic: GE), lithium disilicate glass ceramic blocks (Group e.max CAD: GEC), and zirconia‐reinforced glass ceramic blocks (Group Suprinity: GS) by CAD/CAM technique. After thermocycling, marginal adaptation was evaluated under scanning electron microscope at ×200 magnification. The specimens' fracture strengths were tested in universal test machine, and fracture types were evaluated. Statistical analyses were performed with Kruskal–Wallis test. The highest marginal gap value was found in GEP, but no significant differences were determined among the other four groups (p > .05). Significant differences were observed among the groups in terms of fracture strength (p = .019). The fracture strength values of GEC were significantly higher than GE, GC, and GS (p < .05). Values were not significantly different between the GEC and GEP groups (p > .05). CAD/CAM endocrowns showed better marginal adaptation than heat‐pressed endocrowns. Clinically acceptable marginal gaps were seen in both endocrown types. Both CAD/CAM and heat‐pressed lithium disilicate glass ceramic endocrowns showed higher fracture strength.
Ammonia volatilization from composting with oxidized biochar
Authors: Hestrin Rachel , Enders Akio , Lehmann Johannes
Published: September 2020

Animal manure, agricultural residues, and other sources of biomass can be diverted from the waste stream and composted into valuable fertilizer. However, composting often results in substantial N loss through NH3 gas volatilization. We investigated biochar's capacity to improve NH3–N retention during composting of poultry manure and straw. After 7 wk, total N loss from composting with unoxidized biochar was twofold and sixfold higher than N loss from composting with oxidized biochar and without biochar (307, 142, and 51 mg N g−1 N in the initial compost feedstocks, respectively). When cumulative NH3–N loss was calculated relative to CO2–C loss to account for differences in microbial activity, NH3–N/CO2–C loss from compost with oxidized biochar was 55% lower than from compost with unoxidized biochar (82% lower based on mass balance). Oxidized biochar particles removed from compost after 7 wk retained 16.0 mg N g−1 biochar, compared with only 6.1 mg N g−1 retained by unoxidized biochar, suggesting that N retention by biochar particles provides a mechanism for reduced NH3–N loss. These data show that oxidized biochar enhanced microbial activity, doubled composting rate, and reduced NH3–N loss compared with unoxidized biochar and that biochar's physiochemical characteristics modulate its performance in compost. In particular, the presence of oxidized surface functional groups, which can be increased artificially or through environmental weathering, appear to play an important role in key compost processes. This has implications for other natural and managed systems where pyrogenic organic matter may mediate biological activity and nutrient cycles.
Effect of Billroth‐II versus Roux‐en‐Y reconstruction for gastrojejunostomy after pancreaticoduodenectomy on delayed gastric emptying: A meta‐analysis of randomized controlled trials
Authors: Xiao Yuqing , Hao Xiaofei , Yang Qin , Li Ming , Wen Jun , Jiang Cuina
Published: September 2020

Background/Purpose

Delayed gastric emptying (DGE) is one of the most common complications after pancreaticoduodenectomy (PD). The aim of the present meta‐analysis was to evaluate the effect of Billroth‐II(B‐II) versus Roux‐en‐Y (R‐Y) reconstruction for gastrojejunostomy on DGE after PD.

Methods

A systematic literature search was performed using the electronic database MEDLINE (via PubMed and OVID), EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) of the Cochrane Library to select pertinent randomized controlled trials (RCTs) on this topic from January 1990 to January 2020. The primary outcome was identified as postoperative DGE. Subgroup analysis was established to compare the incidence of grade B and C DGE. Software Revman 5.3 was used for the statistical analysis, summary statistics were calculated using fixed effect model or random effect model.

Results

Five RCTs including a total of 612 patients were eligible for this meta‐analysis. The incidence of grade B and C DGE was significantly lower with the B‐II reconstruction than with the R‐Y reconstruction (8.0% vs. 14.8%, OR = 0.49, 95% CI: 0.26‐0.95, P = 0.03) and the B‐II reconstruction took a shorter operation time (WMD=−7.18, 95% CI: [−13.09, −1.27], P = 0,02). No statistically significant difference was found between the two reconstruction methods in terms of the incidence of postoperative pancreatic fistula (POPF), bile leak, intra‐abdominal abscess, postoperative pneumonia and the length of postoperative hospital stay.

Conclusions

B‐II reconstruction after PD has a lower incidence of grade B and C DGE and shorter operation time compared with R‐Y reconstruction.
J. P. Hill and Katherine Watson's studies of the neural crest in marsupials
Authors: Smith Kathleen K.
Published: September 2020

In the early part of the 20th century, J. P. Hill and K. P. Watson embarked on a comprehensive study of the development of the brain in Australian marsupials. Their work included series from three major groups: dasyurids, peramelids, and diprotodonts, covering early primitive streak through brain closure and folding stages. While the major part of the work was on the development of the brain, in the course of this work they documented that cellular proliferations from the neural plate provided much of the mesenchyme of the branchial arches. These proliferations are now known to be the neural crest. However, except for a very brief note, published shortly after Hill's death, this work was never published. In this study, I present Hill and Watson's work on the development of the early neural plate and the neural crest in marsupials. I compare their findings with published work on the South American marsupial, Monodelphis domestica and demonstrate that patterns reported in Monodelphis are general for marsupials. Further, using their data I demonstrate that in dasyurids, which are ultra‐altricial at birth, the neural crest migrates early and in massive quantities, even relative to other marsupials. Finally, I discuss the historical context and speculate on reasons for why this work was unpublished. I find little support for ideas that Hill blocked publication because of loyalty to the germ layer theory. Instead, it appears primarily to have been a very large project that was simply orphaned as Watson and Hill pursued other activities.
Superhydrophobic needles tipped with 2‐dimensional arrays of plasmonic colloidal nanoparticles for microdroplet SERS analysis
Authors: Li Chunchun , Chai Lin , Chen Qinglu , Ye Ziwei , Xu Yikai , Bell Steven E.J.
Published: September 2020

Aqueous microdroplets strongly attach to metallic needles with superhydrophobic sides and flat hydrophilic tips. Such needles can be made surface‐enhanced Raman spectroscopy (SERS)‐active by adsorbing a layer of densely packed and uniform plasmonic nanoparticles onto the hydrophilic tip. The resulting particle‐tipped needles allow dual enhancement of the Raman signals from microdroplets of low concentration analytes by combining analyte enrichment through solvent evaporation and plasmonic SERS enhancement. The combination of small sample volume, preconcentration, and SERS allows extremely low total amounts of analytes to be detected. Here, we show that with crystal violet as the model analyte, the limit of detection can reach 2 pg. The method can be readily used to fabricate superhydrophobic needles tipped with different types of plasmonic colloidal nanoparticles for enhanced Raman analysis, for example, silver cube tipped needles could be used to detect as little as 2.5 ng of trinitrotoluene.
A recipe for technological innovation: Does hedge fund activism matter? A fuzzy set qualitative comparative analysis
Authors: Vacher Stéphano , Ben Arfa Nouha , Ammari Aymen
Published: September 2020

Hedge fund activism and firm characteristics can be combined to explain targets' engagements in innovative activities. The “difference in difference” regression framework is first performed and shows that target firms experience an improvement in innovation efficiency due to the presence of hedge funds (HFs) activists. The fuzzy set Qualitative Comparative Analysis (fsQCA) perspective, is used, on the HF activism‐technological innovation relationship, which recognizes the existence of conjunctural causation. The main sets from fsQCA leading to high/presence innovation input/output display the presence of activist HFs combined to target mature firms, low leveraged ones, firms performing structural changes, and/or those that better refocus on their core innovation expertise and technologies in these areas.
Can behavioral biases improve the financial capability of microfinance clients in the tribal states of India?
Authors: Chidambaranathan Mani , Guha Samapti
Published: September 2020

Financial capability (FC) of the households involved in microfinance (MF) activities is better than those who are not. MF model, especially the traditional informal group structure, provides a platform for financial socialization and hence, it enables to build the FC of its members. Socioeconomic factors and behavioral economic variables significantly influence the level of FC of the households involved in MF activities. While designing FC enhancement programs, one should consider social capital structures and behavioral economic aspects.