bluuebunny/crossref_metadata_2025 huggingface dataset:
The representativeness of protected areas for Amazonian fish diversity under climate change
Authors: Frederico Renata G. , Dias Murilo S. , Jézéquel Céline , Tedesco Pablo A. , Hugueny Bernard , Zuanon Jansen , Torrente‐Vilara Gislene , Ortega Hernan , Hidalgo Max , Martens Koen , Maldonado‐Ocampo Javier , Oberdorff Thierry
Published: January 2021

The Amazon basin has been subjected to extreme climatic events and according to climate change projections this hydrosystem could face changes in the natural dynamic of flood cycles that support the feeding and reproduction of many fish species, threatening aquatic biodiversity.

Protected areas (PAs) are the main tools used to safeguard the biodiversity in the long term; however, they are fixed areas that could be subject to climate change, questioning their future efficiency in protecting biodiversity.

The Amazon basin currently benefits from a relatively high level of protection as 52% of its catchment area is under the form of true PAs or indigenous lands. However, the capacity of these PAs to protect freshwater biodiversity remains unclear as they have generally been assessed with little regard to freshwater ecosystems and their hydrological connectivity. Here, the aim was to evaluate the effectiveness of PAs in representing the Amazon fish fauna under current and future climatic conditions.

A macroecological approach was used to estimate the minimum size of the geographical range needed by each species to achieve long‐term persistence, by a combined function of range size and body size, two ecological traits known to influence species extinction risk.

In future the Amazon basin could risk losing 2% of its freshwater fish fauna owing to unsuitable climatic conditions, with a further 34% adversely affected. The present Amazon network of PAs will cover the minimum required range for species persistence for more than 60% of the freshwater fish species analysed under the future climate scenario. However, more than 25% of the future susceptible species are currently concentrated in large tributaries and in the central‐lower Amazon floodplain where few PAs occur, highlighting the lack of appropriate conservation actions for these specific water bodies.
Can loyalty be pursued and achieved? An extended RFD model to understand and predict user loyalty to mobile apps
Authors: Wang Chuang , Zhou Rongxin , Lee Matthew K. O.
Published: January 2021

Although millions of mobile apps have been published in the app store, the majority are seldom downloaded or used. This phenomenon has intensified the competition among service providers for user loyalty. There were plenty of studies investigating user loyalty in the mobile‐app context; nevertheless, most failed to identify those true loyalty users who embraced attitudinal and behavioral loyalty. To address this research gap, this study aims to understand and predict user loyalty by an extended RFD model. We propose that recency, frequency, and duration are able to reflect behavioral loyalty, while category frequency rate and category duration rate are representations of attitudinal loyalty. Using the actual data collected from a third‐party app, we calculate the weights of each variable through the entropy weight method, evaluate users' loyalty in two dimensions, and classify users into four groups (i.e., true loyalty, latent loyalty, moderate loyalty, and no loyalty). We also conduct a dynamic analysis to investigate how users move across different loyalty conditions. The results indicate that majority of users tend to stay on their initial loyalty conditions. For those who have changed their loyalty conditions, it is found that true loyalty users are more likely to become latent loyalty users.
Power in the U.S. political economy: A network analysis
Authors: Malik Nishant , Spencer David , Bui Quang Neo
Published: January 2021

Many features of the U.S. political economy arise from the interactions between large political and economic institutions, and yet we know little about the nature of their interactions and the power distribution between these institutions. In this paper, we present a detailed analysis of networks of U.S.‐based organizations, where edges represent three different kinds of relationships, namely owner–owned (ownerships), donor–donee (donations), and service provider–payee (transactions). Our findings suggest that in the ownerships network, the financial organizations form the core, and banking organizations hold strategic locations in the network. In the transactions network, the government organizations and agencies form the core, and defense‐related organizations form the backbone. In contrast, with the donations network, no specific domain of organizations forms either the core or the backbone.
Historical evolution of spheroids and organoids, and possibilities of use in life sciences and medicine
Authors: Sakalem Marna Eliana , De Sibio Maria Teresa , da Costa Felipe Allan da Silva , de Oliveira Miriane
Published: January 2021

Background

An impressive percentage of biomedical advances were achieved through animal research and cell culture investigations. For drug testing and disease researches, both animal models and preclinical trials with cell cultures are extremely important, but present some limitations, such as ethical concern and inability of representing complex tissues and organs. 3D cell cultures arise providing a more realistic in vitro representation of tissues and organs. Environment and cell type in 3D cultures can represent in vivo conditions and thus provide accurate data on cell‐to‐cell interactions, and cultivation techniques are based on a scaffold, usually hydrogel or another polymeric material, or without scaffold, such as suspended microplates, magnetic levitation, and microplates for spheroids with ultra‐low fixation coating.

Purpose and scope

This review aims at presenting an updated summary of the most common 3D cell culture models available, as well as a historical background of their establishment and possible applications.

Even though 3D culturing is incapable of replacing other current research types, they will continue to substitute some unnecessary animal experimentation, as well as complement monolayer cultures.

Conclusion

In this aspect, 3D culture emerges as a valuable alternative to the investigation of functional, biochemical, and molecular aspects of human pathologies.
A common framework for integrated and continuous biomanufacturing
Authors: Coffman Jonathan , Brower Mark , Connell‐Crowley Lisa , Deldari Sevda , Farid Suzanne S. , Horowski Brian , Patil Ujwal , Pollard David , Qadan Maen , Rose Steven , Schaefer Eugene , Shultz Joseph
Published: January 2021

There is a growing application of integrated and continuous bioprocessing (ICB) for manufacturing recombinant protein therapeutics produced from mammalian cells. At first glance, the newly evolved ICB has created a vast diversity of platforms. A closer inspection reveals convergent evolution: nearly all of the major ICB methods have a common framework that could allow manufacturing across a global ecosystem of manufacturers using simple, yet effective, equipment designs. The framework is capable of supporting the manufacturing of most major biopharmaceutical ICB and legacy processes without major changes in the regulatory license. This article reviews the ICB that are being used, or are soon to be used, in a GMP manufacturing setting for recombinant protein production from mammalian cells. The adaptation of the various ICB modes to the common ICB framework will be discussed, along with the pros and cons of such adaptation. The equipment used in the common framework is generally described. This review is presented in sufficient detail to enable discussions of IBC implementation strategy in biopharmaceutical companies and contract manufacturers, and to provide a road map for vendors equipment design. An example plant built on the common framework will be discussed. The flexibility of the plant is demonstrated with batches as small as 0.5 kg or as large as 500 kg. The yearly output of the plant is as much as 8 tons.
Red cell manufacturing using parallel stirred‐tank bioreactors at the final stages of differentiation enhances reticulocyte maturation
Authors: Han So Yeon , Lee Eun Mi , Lee Janghan , Lee Hyosang , Kwon Amy M. , Ryu Ki Young , Choi Won‐Seok , Baek Eun Jung
Published: January 2021

The aim of this study was to develop a robust, quality controlled, and reproducible erythroid culture system to obtain high numbers of mature erythroblasts and red blood cells (RBCs). This was achieved using a fully controlled stirred‐tank bioreactor by the design of experiments (DOE) methods in the serum‐free medium by defining the appropriate culture parameters. Human cord blood CD34+ cells were first cultured in static flasks and then inoculated to stirred‐tank bioreactors. Cell diameter was gradually decreased and final RBC yields were significantly higher when cells were inoculated at sizes smaller than 12 μm. The larger immature cells in the basophilic stage did not survive, while smaller mature erythroid cells were successfully expanded at high agitation speeds, demonstrating that appropriate seeding timing is critical. A high inoculation cell density of 5 × 106 cells/ml was achieved reaching 1.5 × 107 cells/ml. By using DOE analysis fitted to precise stages of erythropoiesis, we were able to acquire the optimal culture parameters for pH (7.5), temperature (37°C), dissolved oxygen, agitation speed (500 rpm), inoculation timing (cell diameter 12–13 μm), media feeding regimen, and cell seeding density (5 × 106 cells/ml). The final pure RBCs showed appropriate functions compared with fresh donor RBCs, confirming that manufacturing mature RBCs with reproducibility is possible.
Application of metabolic modeling for targeted optimization of high seeding density processes
Authors: Brunner Matthias , Kolb Klara , Keitel Alena , Stiefel Fabian , Wucherpfennig Thomas , Bechmann Jan , Unsoeld Andreas , Schaub Jochen
Published: January 2021

Process intensification by application of perfusion mode in pre‐stage bioreactors and subsequent inoculation of cell cultures at high seeding densities (HSD) has the potential to meet the increasing requirements of future manufacturing demands. However, process development is currently restrained by a limited understanding of the cell's requirements under these process conditions. The goal of this study was to use extended metabolite analysis and metabolic modeling for targeted optimization of HSD cultivations. The metabolite analysis of HSD N‐stage cultures revealed accumulation of inhibiting metabolites early in the process and flux balance analysis led to the assumption that reactive oxygen species (ROS) were contributing to the fast decrease in cell viability. Based on the metabolic analysis an optimized feeding strategy with lactate and cysteine supplementation was applied, resulting in an increase in antibody titer of up to 47%. Flux balance analysis was further used to elucidate the surprisingly strong synergistic effect of lactate and cysteine, indicating that increased lactate uptake led to reduced ROS formation under these conditions whilst additional cysteine actively reduced ROS via the glutathione pathway. The presented results finally demonstrate the benefit of modeling approaches for process intensification as well as the potential of HSD cultivations for biopharmaceutical manufacturing.
Hungarian validation of the Buss–Perry Aggression Questionnaire—Is the short form more adequate?
Authors: Zimonyi Szabolcs , Kasos Krisztian , Halmai Zsuzsa , Csirmaz Luca , Stadler Helga , Rózsa Sándor , Szekely Anna , Kotyuk Eszter
Published: January 2021

Objective

We aim to provide a publicly available Hungarian version of the BPAQ; compare the BPAQ factors to other personality traits; and compare both the original BPAQ factor structure provided by Buss and Perry (J. Pers. Soc. Psychol., 63, 1992, 452), the revised BPAQ‐SF factor structure by Bryant and Smith (J. Res. Pers., 35, 2001, 138), and the BAQ by Webster et al. (Aggress. Behav., 40, 2014, 120).

Methods

The validation of the Hungarian version of the BPAQ was carried out on a Hungarian university sample (N = 841). There were three main focuses of data analysis: descriptive statistics, correlations, and confirmatory factor analyses.

Results

CFA‐related statistics showed an adequate fit for the BPAQ 4 factors; however, contrary to prior validations of BPAQ, we were not able to clearly define the verbal aggression factor. We found that the shorter form of the BPAQ has a better model fit on our sample than the original form, while the model fit of the BAQ was in‐between these. BPAQ scales showed low to moderate relationship with the Barratt Impulsivity Scale and Hospital Anxiety and Depression Scale.

Conclusion

Both the BPAQ and the BPAQ‐SF, also the BAQ provide acceptable model fitting on a Hungarian sample of university students. While most of BPAQ items provided adequate loadings on their hypothesized factors, two items (21 and 27) did not. We argue this is the result of conceptual inaccuracy of the original items.
Contact with older people, ageism, and containment behaviours during the COVID‐19 pandemic
Authors: Visintin Emilio Paolo
Published: January 2021

To reduce and slow the spread of the coronavirus during the pandemic, people throughout countries are asked to adopt a series of prevention behaviours such as keeping physical distance and using protective devices (containment behaviours). Vulnerability of older people during the pandemic has been stressed by mass‐media and in political communication, calling for protection of this sector of the population. Based on intergroup contact theory and on the stereotype content model, I conducted a correlational study during the coronavirus lockdown in Italy, analysing contact with older people before the pandemic, ageism, and containment behaviours. Quality of contact with older people, favourable attitudes toward older people, and benevolent ageism were found to be positively associated with containment behaviours. Findings suggest that positive intergenerational relations are likely beneficial for public health.
Fluorophosphonates on‐Demand: A General and Simplified Approach toward Fluorophosphonate Synthesis
Authors: Dutra Jason K. , Foley Timothy L. , Huang Zhen , Fisher Ethan L. , Lachapelle Erik A. , Mahapatra Subham , Ogilvie Kevin , Butler Todd W. , Bellenger Justin , Devraj Majmudar Jaimeen , am Ende Christopher W.
Published: January 2021

Herein, we report a general and simplified synthesis of fluorophosphonates directly from p‐nitrophenylphosphonates. This FP on‐demand reaction is mediated by a commercially available polymer‐supported fluoride reagent that produces a variety (25 examples) of fluorophosphonates in high yields while only requiring reagent filtration for pure fluorophosphonate isolation. This reaction protocol facilitates the rapid profiling of serine hydrolases with diverse and novel sets of activated phosphonates with differential proteome reactivity. Moreover, slight modification of the procedure into a reaction‐to‐assay format has enabled additional screening efficiency.
Mortality in spontaneous coronary artery dissection: A systematic review and meta‐analysis
Authors: Adams Cobi , He Maggie , Hughes Ian , Singh Kuljit
Published: January 2021

Objective

The aim of this systematic review and meta‐analysis was to provide a comprehensive estimate for spontaneous coronary artery dissection (SCAD) related mortality, and explore factors associated with an increased risk of death.

Background

SCAD is an infrequent but increasingly recognized cause of acute coronary syndrome. Despite a growing body of evidence, there have been few detailed examinations of SCAD associated mortality.

Methods

We searched MEDLINE, EMBASE, Cochrane, Web of Science and Google Scholar databases through May 7, 2020. We included studies reporting mortality data, confirmed SCAD with coronary angiography and included ≥10 participants. We excluded non‐English studies, conference abstracts, review articles and duplicate datasets. Random‐effects meta‐analysis and meta‐regression were used to evaluate estimates and predictors of mortality.

Results

From an initial 1,131 articles, 34 studies with 2,817 patients were eligible for inclusion. The weighted mean age was 50 years, and 84% of participants were female. The pooled estimate for SCAD mortality was 1% (Proportion 0.01; 95% CI, 0.00–0.02). The mean duration of follow‐up was 33 months. Meta‐regression showed male sex was associated with 3.5‐fold increased odds of mortality (OR, 3.50; 95% CI, 1.22–10.03). In addition, smoking (current or previous) was associated with a 15‐fold increased risk of mortality (OR 15.32; 95% CI, 2.88–81.41).

Conclusions

This meta‐analysis has shown that SCAD is associated with favorable survival outcomes with an estimated mortality of 1% over a mean follow‐up period of 33 months. We also found male sex and smoking were associated with an increased risk of mortality.
Iron Catalyzed Double Bond Isomerization: Evidence for an FeI/FeIII Catalytic Cycle
Authors: Woof Callum R. , Durand Derek J. , Fey Natalie , Richards Emma , Webster Ruth L.
Published: January 2021

Iron‐catalyzed isomerization of alkenes is reported using an iron(II) β‐diketiminate pre‐catalyst. The reaction proceeds with a catalytic amount of a hydride source, such as pinacol borane (HBpin) or ammonia borane (H3N⋅BH3). Reactivity with both allyl arenes and aliphatic alkenes has been studied. The catalytic mechanism was investigated by a variety of means, including deuteration studies, Density Functional Theory (DFT) and Electron Paramagnetic Resonance (EPR) spectroscopy. The data obtained support a pre‐catalyst activation step that gives access to an η2‐coordinated alkene FeI complex, followed by oxidative addition of the alkene to give an FeIII intermediate, which then undergoes reductive elimination to allow release of the isomerization product.
The Prospect of Dimensionality in Porous Semiconductors
Authors: Fritz Patrick W. , Coskun Ali
Published: January 2021

With the advent of silicon‐based semiconductors, a plethora of previously unknown technologies became possible. The development of lightweight low‐dimensional organic semiconductors followed soon after. However, the efficient charge/electron transfers enabled by the non‐porous 3D structure of silicon is rather challenging to be realized by their (metal‐)organic counterparts. Nevertheless, the demand for lighter, more efficient semiconductors is steadily increasing resulting in a growing interest in (metal‐)organic semiconductors. These novel materials are faced with a variety of challenges originating from their chemical design, their packing and crystallinity. Although the effect of molecular design is quite well understood, the influence of dimensionality and the associated change in properties (porosity, packing, conjugation) is still an uncharted area in (metal‐)organic semiconductors, yet highly important for their practical utilization. In this Minireview, an overview on the design and synthesis of porous semiconductors, with a particular emphasis on organic semiconductors, is presented and the influence of dimensionality is discussed.
Rational Molecular Design of Multifunctional Blue‐Emitting Materials Based on Phenanthroimidazole Derivatives.
Authors: Chen Xiang , Zhang Hao , Tan Hong‐Ji , Yang Liu , Qin Peng , Zheng Xu‐Hui , Tang Shan‐Shun , Liu Yu , Tong Qing‐Xiao
Published: January 2021

High‐performance deep‐blue emitters with external quantum efficiencies (EQEs) exceeding 5 % are still scarce in organic light‐emitting diodes (OLEDs). In this work, by introducing a [1,2,4]triazolo[1,5‐a] pyridine (TP) unit at the N1 position of phenanthroimidazole (PI), two luminescent materials, PTPTPA and PTPTPA, were obtained. Systematic photophysical analysis showed that the TP block is suitable for constructing hybridized local and charge‐transfer (HLCT) emitters. Its moderate electron‐withdrawing ability and rigid planar structure can enhance the CT component while ensuring color purity. In addition, compared with PTPTPA, the additional phenyl ring of PTPBPTA not only increased the oscillator strength, but also decreased the Stokes shift. TDDFT calculations pointed out facile reverse intersystem crossing processes in PTPTPA from high‐lying triplet states to the singlet excited state. A nondoped device based on PTPTPA as emitter showed impressive performance with EQEmax of 7.11 % and CIE coordinates of (0.15, 0.09). At the same time, it was also an efficient host for yellow and red phosphorescent OLEDs. By doping yellow (PPYBA) and red (BTPG) phosphorescent dyes into PTPTPA, a white OLED with a high EQE of 23.85 % was achieved. The successful design of PTPTPA not only provided an optimization choice for OLED emitters, but also demonstrated the empirical rules for the design of multifunctional deep‐blue emitters.
Perspektiven für Hochspannungs‐Gleichstrom‐Übertragung on‐ und offshore
Authors: Siebels Carsten
Published: January 2021

Das mögliche Einsatzgebiet von Hochspannungs‐Gleichstrom‐Übertragung (HGÜ) in Mitteleuropa liegt dort, wo elektrische Energie per See‐ oder Erdkabel über große Entfernungen übertragen werden soll. Beispiele für die Berechnung der Netzverluste werden gegeben. Es werden anhand der Angaben im Netzentwicklungsplan Strom 2019–2030 die spezifischen Kosten der Energieübertragung mittels HGÜ‐Kabeln ausgewiesen. Diese werden für verschiedene Belastungsgrade ermittelt und mit Drehstrom‐Freileitungen und ‐Kabeln verglichen. Es werden Alternativen zur Stromübertragung mittels HGÜ dargestellt.
Safety, Pharmacokinetics, and Neutralizing Activity of SYN023, a Mixture of Two Novel Antirabies Monoclonal Antibodies Intended for Use in Postrabies Exposure Prophylaxis
Authors: McClain J. Bruce , Chuang Ariel , Moore Susan M. , Tsao Eric
Published: January 2021

SYN023 is a mixture of 2 humanized monoclonal antirabies antibodies (CTB011, CTB012). Two first‐in‐human studies evaluated ascending intramuscular (IM) injected doses (Study SYN023‐001; N = 15) and IM vs subcutaneous (SC) administration (Study SYN023‐003; N = 35) in healthy adults. In both studies, end points were safety, pharmacokinetics (PK), pharmacodynamics/rabies virus neutralizing activity (RVNA), and immunogenicity (anti‐SYN023 antibodies). Adverse events were mild and infrequent at all doses tested by IM injection (0.3 mg/kg, 1.0 mg/kg, 2.0 mg/kg), or by SC injection (0.3 mg/kg). There were no apparent trends in adverse event frequency or nature with increased dose or with administration route. Serum PK of SYN023 component antibodies appeared comparable to each other at each dose tested and when administered IM versus SC with serum exposure doubling over the second week after administration. At the lowest dose tested (0.3 mg/kg) by either IM or SC injection, RVNA levels exceeded the concentration generally accepted as protective against rabies (≥0.5 IU/mL) by day 1 after administration. Supra‐inhibitory levels persisted >42 days. RVNA increased with higher doses. Anti‐CTB011 and anti‐CTB012 antibodies occurred with no apparent effect on PK or safety. These data support the potential use of SYN023 in antirabies postexposure prophylaxis.
Valuing the invaluable: park visitors' perceived importance and willingness to pay for urban park trees in Pakistan
Authors: Malik Aisha , Zubair Muhammad , Manzoor Syed Amir
Published: January 2021

In complex urban systems, urban parks are rare hot spots of nature, responsible for delivering a range of ecosystem services. Trees are critically important components of urban parks that provide many benefits, and, at the same time, face challenges such as lack of funds, mismanagement, climate change, pests, and diseases. There is a growing need to increase the urban tree cover to sustain urban ecosystems. Successful policymaking requires engagement with all stakeholders, especially park users. An understanding of how people's perceptions of the benefits and challenges faced by urban park trees is pivotal to making decisions that have long‐standing support. We surveyed 521 park visitors in Multan, Pakistan, to assess their valuation of urban park trees, their understanding of the challenges faced by trees, and their willingness to pay (WTP) for increasing tree cover in urban parks. We found that people widely appreciated the ecosystem services provided by park trees. Provision of oxygen, shade, and clean air was considered the greatest benefits while cutting down, lack of space, and urbanization were perceived as the biggest challenges to trees. Respondents showed a WTP and believed in government–public cooperation for increasing tree cover. Income, age, and education were significant predictors of WTP. The study reflects findings in other development and geography contexts and highlights the need for broader dissemination of information on critical threats to park trees and underlines the potential for engaging locally to maximize effectively in the management of park trees.
Local landscape position impacts demographic rates in a widespread North American steppe bunchgrass
Authors: Shriver Robert K. , Campbell Erin , Dailey Christopher , Gaya Heather , Hill Abby , Kuzminski Sonya , Miller‐Bartley Margaret , Moen Kyle , Moettus Riga , Oschrin Emma , Reese Devin , Simonson Molly , Willson Alice , Parker Timothy H.
Published: January 2021

Understanding the environmental drivers of demographic rates and population dynamics over space and time is critical for anticipating how species will respond to climate change. While the influence of temporal environmental variation and large environmental gradients are well recognized, less is known about how local topography and landscape position influence demography over small spatial scales. Here, we investigate how local landscape position (north‐ vs. south‐facing aspects) influence the demographic rates and population growth of a common bunchgrass in western North America, bluebunch wheatgrass (Pseudoroegneria spicata), using 6 annual censuses measuring growth, survival, and reproductive output. We found notably lower survival on south‐facing slopes, particularly among smaller individuals. In contrast, south‐facing slopes maintained comparatively high reproductive output in most years, measured both as spikes per plant and spikelets per spike. When we combined these data in demographic models, we found that lower survival among small individuals and greater reliance on reproduction mean south‐facing slopes would generally have to maintain higher recruitment for a stable population. Our results highlight the important influence that landscape position and local topography can have in driving population trends. As conditions warm and dry with climate change (north‐faces becoming similar to current south‐facing slope conditions), bluebunch wheatgrass may become more reliant on reproduction to maintain viable populations and more sensitive to variability in recruitment.
Synthesis of Alkyl Bridged‐Tris‐α‐Amino Acids as C3‐Symmetric and Linear Linkers
Authors: Uchino Ayumi , Tsukano Chihiro , Imamoto Tsuneo , Irie Kazuhiro
Published: January 2021

Although bis‐α‐amino acids have been used to synthesize dimer models of aggregative peptides involved in neurodegenerative diseases, tris‐α‐amino acids are employed to a lesser extent for trimer models. The reported tris‐α‐amino acids substituted on the 1,3,5‐positions of an aromatic ring are not suitable for mimicking trimers due to their low flexibility and high planarity. Here, we design and synthesize two new alkyl bridged‐tris‐α‐amino acids with Fmoc protecting groups as new flexible linkers for trimer models.
Glycosamine Derivatives through Metal‐Catalyzed C−N Bond Formation on Protected and Unprotected 2‐Iodoglycals
Authors: Malinowski Maciej , Banoun Camille , de Robichon Morgane , Lubin‐Germain Nadège , Ferry Angélique
Published: January 2021

Glycosamines are important building blocks of natural biopolymers. The development of synthetic routes to such glycoside family is of big interest in terms of biological application. Herein, access to glycosamine derivatives through dual nickel/copper‐catalyzed C−N bond formation via a cross‐coupling reaction is presented. Diverse benzyl‐ and cyclic amide‐containing glycals were successfully synthesized in moderate to excellent yields starting from perbenzylated and protecting group‐free 2‐iodoglycals. 16 examples presenting d‐glucal or d‐galactal configuration and an electron‐rich or electron‐poor amide moiety in position 2 of the carbohydrate are obtained by this methodology. Post‐functionalization by hydrogenolysis conditions of three synthesized compounds allows access to d‐mannosamine and d‐talosamine mimics.
Synthesis of Sheet Like Nanostructures of NiO Using Potassium Dichromate as Surface Modifying Agent for the Sensitive and Selective Determination of Amlodipine Besylate (ADB) Drug
Authors: Ahmed Khand Aftab , Ahmed Lakho Saeed , Tahira Aneela , Ahmed Mansoor , Aftab Umair , Abro Muhammad Ishaq , Juno Awais Ahmed , Nafady Ayman , Ibupoto Zafar Hussain
Published: January 2021

The monitoring of hypertension drugs is very critical and important to sustain a healthy life. In this study, we have synthesized nickel oxide (NiO) nanostructures using potassium dichromate as surface modifying agent by hydrothermal method. These NiO nanostructures were found highly active for the oxidation of ADB besylate (ADB). The unit cell structure and morphology were investigated by scanning electron microscopy (SEM) and powder X‐ray diffraction (XRD) techniques. The SEM study has confirmed the nano sheet like morphology and XRD analysis has described the cubic unit arrays of NiO. After the physical characterization, NiO nanostructures were used to modify the surface of glassy carbon electrode (GCE) by drop casting method. Then cyclic voltammetry (CV) was used to characterize the electrochemical activity of NiO nanostructures in the0.1 M phosphate buffer solution of pH 10.0 and a well resolved oxidation peak was identified at 0.70 V. The linear range for the NiO nanostructures was observed from 20–90 nM with a regression coefficient of 0.99 using CV. The calculated limit of detection (LOD) was 2.125 nM and the limit of quantification (LOQ) was 4.08 nM. Further to validate the CV calibration plot, an amperometry experiment was performed on the NiO nanostructures and sensors exhibited a linear range of 10 nM to 115 nM with LOD of 1.15 nM. The proposed approach was successfully used for the determination of ADB from commercial tablets and it reveals that the sensor could be capitalized to monitor ADB concentrations from pharmaceutical products. The use of potassium dichromate as a surface modifying agent for the metal oxide nanostructures may be of great interest to manipulate their crystal and surface properties for the extended range of biomedical and energy related applications.
Lead‐free metal halide perovskites for light‐emitting diodes
Authors: Lu Jianxun , Yan Chuanzhong , Feng Wenjing , Guan Xiang , Lin Kebin , Wei Zhanhua
Published: January 2021

Metal halide perovskites (MHPs) have been developing rapidly in recent years due to their outstanding optoelectronic properties and tremendous contributions from worldwide researchers. The external quantum efficiencies of perovskite light‐emitting diodes (Pero‐LEDs) have all exceeded 20% for the green, red, and near‐infrared emitting ones. However, the toxicity and instability issues of the lead‐based MHPs are still big problems limiting their practical applications. The applications of the lead‐free MHPs (LFMHPs) are emerging as one of the most promising strategies to tackle these issues. Compared with lead‐based MHPs, the LFMHPs show better environment stability and broader emission regions from the violet to near‐infrared wavelength. Thanks to numerous contributions made by the researchers, great progress has already been made for the LFMHPs. For example, the photoluminescence quantum yield has reached near 100%. However, the performances of the lead‐free Pero‐LEDs are still lagging compared with their lead‐based counterparts. In this review, we comprehensively summarize the synthesis developments of LFMHPs and their applications in the down‐conversion white LEDs and electroluminescent Pero‐LEDs. Moreover, some suggestions and outlooks of the lead‐free Pero‐LEDs developments are proposed in the end.

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Toward a Universal Acute Fish Threshold of Toxicological Concern
Authors: Plugge Hans , Das Nihar , Kostal Jakub
Published: January 2021

Threshold of toxicological concern (TTC) is a concept that has been around for decades in human health sciences. Ecotoxicology recently adopted a variant of this concept as eco-TTC. Adoption of the concept of TTC considerably reduces the amount of animal testing required for regulatory purposes. We provide an application of a universal TTC for the entirety of acute fish toxicity data (i.e., establishment of an exposure level below which there would be minimal probability of acute fish toxicity for any chemical, without consideration of mechanism of action). We calculated TTC values for a number of subgroups using various approaches. These approaches were evaluated using data from a cohort of 69 999 acute fish toxicological assays. This database was normalized/curated for units, exposure duration, quality assurance/control, and duplicates, which reduced it to 47 694 assays. Data were not normally but log-normally distributed, making geometric means the most appropriate statistical parameter. Thus, we developed descriptive statistics using geometric means with 95, 99, and 99.9% confidence intervals. Various assessment factors (akin to predicted-no-effect concentration derivation) were applied to the geometric means to derive TTCs. Other approaches employed were the calculation of y = 0 intercepts as well as development of 95 and 99.75% cutoffs of cumulative data as well as modular uncertainty scoring tool (MUST) analysis. All of the methodologies derived highly congruent TTCs ranging from to 2 to 8 μg/L except for the 99.75th percentile cutoff of 0.3 μg/L. The data would be most useful in making a binary testing/no testing required decision. For acute fish toxicity, a TTC value of 2 μg/L was most appropriate, based on the 95th percentile of data distribution without any assessment factor. Environ Toxicol Chem 2021;40:1740–1749. © 2021 SETAC
Effects of Low Doses of Herbicides on Different Endpoints in the Life Cycle of Nontarget Terrestrial Plants
Authors: Mathiassen Solvejg K. , Boutin Céline , Strandberg Beate , Carpenter David , Damgaard Christian
Published: January 2021

Herbicide drift may cause adverse effects on natural and seminatural plant communities, and it has been debated whether the current ecological risk assessments are adequate to protect nontarget terrestrial plant species. In the present study, 9 nontarget terrestrial plant species with different lifespans (3 annual/6 perennial) belonging to 6 different plant families were exposed to 4 herbicides with different modes of action at the vegetative (6–8 leaf) and reproductive (bud) stages separately. The plant tests were conducted under controlled conditions in 2 greenhouses, 1 located in Denmark and 1 in Canada. For both growth stages, effects were recorded on vegetative (above-ground biomass 3 wk after treatment) and reproductive endpoints (number and germinability of seeds). In most cases, responses following exposure at the juvenile stage were greater than responses following exposure at the reproductive stage. For the combinations of herbicides and plant species included in the present study, we found that the sensitivities of vegetative and reproductive endpoints were equal, or else vegetative endpoints were more sensitive than reproductive endpoints. We also found that annual species were more sensitive than perennial species. The overall conclusions cover many different response patterns, and it is evident that some effects may not be found in the currently used standard tests. Generally, more pronounced effects were obtained in Denmark compared with Canada, highlighting the fact that even under standardized test conditions and following common guidelines, several uncontrollable factors can still induce variable results. Environ Toxicol Chem 2021;40:1389–1404. © 2021 SETAC
Exposure and Risk Assessment of Hg, Cd, As, Tl, Se, and Mo in Women of Reproductive Age Using Urinary Biomonitoring
Authors: Coscollà Clara , Sánchez Alfredo , Corpas-Burgos Francisca , López Antonio , Pérez Rosa , Kuligowski Julia , Vento Máximo , Yusà Vicent
Published: January 2021

The present study analyzed the exposure and risk assessment of 4 toxic (Hg, Cd, As, Tl) and 2 essential (Se, Mo) elements in 119 Spanish women of reproductive age. The focus was on the elements for which risk-based benchmark, biomonitoring equivalents, or health-related human biomonitoring values have already been established. All elements presented frequencies of detection of 100% (greater than the limit of detection), except for Cd (99%). The 95th percentile concentrations were, for the toxic metals, 358.37 µg/L (total As), 1.10 µg/L (Cd), 0.41 µg/L (Tl), and 3.03 µg/L (total Hg) and, for the essential elements, 68.95 µg/L (total Se) and 154.67 (Mo). We examined sociodemographic factors and dietary habits of women as predictors of urinary metal concentrations. Arsenic was positively associated with fish, shellfish, and canned fish consumption, whereas Mo was found to be associated with the consumption of cereals and pastry products. Maternal urine levels of As were negatively correlated with gestational age. In a risk-assessment context, hazard quotients (HQs) using the 95th percentile ranged from 0.08 (Tl) to 15.1 (urinary speciated As), with Cd presenting an HQ of 1.1 (95th percentile). None of the essential metals presented concentrations higher than their upper intake level; however, 3% of the mothers showed lower levels of Se than the estimated average requirement (EAR) biomonitoring equivalent, and 20% of the mothers were found to have lower levels of Mo than the EAR biomonitoring equivalent, suggesting a nutritionally inadequate diet. Environ Toxicol Chem 2021;40:1477–1490. © 2021 SETAC

Abstract

Levels, predictors, and risk assessment for toxic and essential elements in mothers.
Should stock returns predictability be ‘hooked on’ long‐horizon regressions?
Authors: Dergiades Theologos , Pouliasis Panos K.
Published: January 2021

This paper re‐examines stock returns predictability over the business cycle using price‐dividend and price‐earnings valuation ratios as predictors. Unlike prior studies that habitually implement long‐horizon/predictive regressions, we conduct a testing framework in the frequency domain. Predictive regressions support no predictability; in contrast, our results in the frequency domain verify significant predictability at medium and long horizons. To robustify predictability patterns, the analysis is executed repetitively for fixed‐length rolling samples of various sizes. Overall, the stock returns are predictable for wavelengths higher than 5 years. This finding is robust and independent of time, window size and predictor.
Repeat induced abortion in 30 Chinese provinces: A cross‐sectional study
Authors: Luo Hao , Wu Shangchun , Wang Kun , Xu Jialin , Tang Longmei , Temmerman Marleen , Zhang Wei‐Hong ,   the INPAC consortium
Published: January 2021

Objective

To report the proportion and determinants of repeat induced abortions in China.

Methods

Cross‐sectional data were collected of 79 954 women who received an induced abortion from 297 hospitals across 30 Chinese provinces in 2013, using a stratified cluster sampling design. Logistic and Poisson regression models were fitted to identify characteristics associated with repeat abortion. Putative factors included age, household registration (hukou) status, marital status, education, occupation, reproductive history, and current contraceptive practices.

Results

Of all abortions, 65.2% were repeat induced abortions. The proportion of repeat abortions varied substantially across provinces, from 36.9% in Qinghai to 85% in Hubei. The strongest factors associated with repeat induced abortion were being older than 40 years (adjusted odds ratio [ORadj] 7.0, 95% confidence interval [CI] 6.2–7.9), divorced or widowed (ORadj 2.1, 95% CI 1.6–2.7), and using oral contraceptives (ORadj 2.1, 95% CI 1.9–2.3).

Conclusion

A high proportion of repeat induced abortion was observed across many Chinese provinces, highlighting the need to reduce the incidence of unwanted pregnancy. Several sociodemographic and clinical factors were found to be significantly associated with repeat abortions and should be considered in post‐abortion family planning services.
SegCaps: An efficient SegCaps network‐based skin lesion segmentation in dermoscopic images
Authors: Kosgiker Gouse Mohiuddin , Deshpande Anupama , Kauser Anjum
Published: January 2021

This research aims to improve the efficiency of skin lesion segment locations for the given input image of skin cancer using a combination of recently modified segmentation algorithms. Skin lesion segmentation is still a challenging task in medical image analysis because of the low contrast and high noise produced by dermoscopic imaging. Previous works extracted spatially‐oriented information but failed in terms of training. They were based on convolutional neural networks (CNNs), which require extensive training time. Current results show 91% to 93% efficiency in segmentation, but the proposed segmentation capsule network (SegCaps) in this research has improved it up to 98% by adding four pre‐processing sequential processes in combinations with SegCaps algorithms. The performance of the proposed SegCaps model was evaluated on two different datasets—ISBI 2017 and PH2 and implemented on the MatlabR2017b software. The chosen metrics were Jaccard co‐efficient, dice similarity co‐efficient, accuracy, sensitivity, and specificity for validation.
Developing the non‐dimensional framework for water distribution formulation to evaluate sprinkler irrigation*
Authors: Li Ang , Mu Xinyuan , Zhao Xia , Xu Jiamin , Khayatnezhad Majid , Lalehzari Reza
Published: January 2021

Improving the application efficiency and leaching of solutes from the root zone in a sprinkler irrigation system are directly related to the uniformity of water distribution at the field surface. The coefficient of uniformity and distribution uniformity are affected by changes in wind speed and its direction, sprinkler characteristics and variations in operating pressure. The objective of this paper is to present modified equations for evaluating pressurized irrigation systems based on non‐dimensional infiltrated depths. The equations were obtained by four data groups including the average of the measured infiltration depths in any quarter. Coefficient of uniformity (CU), distribution uniformity (DU), application efficiency (Ea) and deep percolation (DP) were used as performance indicators to evaluate the sprinkler irrigation system. The suggested method was compared to the existing approach to assess the evaluation indicators. Three data sets of observed information for wheel‐move, permanent solid set and semi‐solid set irrigation systems were collected in Chaharmahal and Bakhtiari provinces to evaluate the proposed formulation. Furthermore, the relationships between CU and DU were analysed for three scenarios of infiltration depth. Results show that the application efficiency was 12% less than previous equations because of using four average values.
Enriched cancer stem cells, dense stroma, and cold immunity: Interrelated events in pancreatic cancer
Authors: Mortezaee Keywan
Published: January 2021

Cold tumors generally show low mutational burden and low infiltration of effector T cells. The pancreas, prostate, ovary, breast, and colon are placed into the category of cold tumors. In such tumors, effector T cells are either excluded from the tumor area or taken away from being in contact with tumor cells. The stromal reaction in the form of desmoplasia is important for the pathogenesis of tumors like the pancreas. Besides acting as a barrier for the penetration of drugs into the tumor area, the dense stroma presumably creates an immunosuppressive tumor microenvironment (TME), which accounts for low responses from tumor to immunotherapy. Cancer stem cells (CSCs) are an important part of the immunosuppressive complex within the TME. The presence of CSCs within the TME is related negatively to the activity of the antitumor immune system. Here, the question is how desmoplastic aggregates can influence the functionality of CSCs for promoting a cold pancreatic tumor immunity? This review is aimed at responding to this question, the disruption of which can be an effective strategy for improving responses from cold tumors to immunotherapy.
Potential effect of adrenomedullin on metabolic and endocrinal dysfunctions in the experimentally induced polycystic ovary: Targeting implication of endoplasmic reticulum stress
Authors: El‐Saka Mervat H. , Barhoma Ramez A. , Ibrahim Rowida R. , Elsaadany Amira , Alghazaly Ghada M. , Elshwaikh Shereef , Marea Karima E. , Madi Nermin M.
Published: January 2021

This study investigated the potential effect of adrenomedullin (ADM) on metabolic and endocrinal dysfunctions in experimentally induced polycystic ovary. Twenty‐four female Wistar rats were allocated into three groups: control; polycystic ovary syndrome (PCOS) in which PCOS was induced by letrozole, orally in a dose of 1 mg/kg once daily for 3 weeks; and ADM group in which ADM was injected intraperitonally in a dose of 3.5/μg/twice daily for 4 weeks. At the end of the experimental period, the serum sex hormone profile, ADM, fasting glucose, insulin, homeostatic model assessment of insulin resistance, and lipid parameters were determined. Ovarian tissue homogenates were used to determine malondialdehyde, total antioxidant capacity, glutathione peroxidase activity, tumor necrosis factor α, interleukin 6, B cell lymphoma‐2 (Bcl‐2), and Bcl‐2 associated X protein. The profibrotic growth factors, including transforming growth factor β1 and connective tissue growth factor, were determined; and also, the relative gene expression of endoplasmic reticulum (ER) stress, including (Xbox‐binding protein‐1 [XBP‐1], activating transcription factor 6 [ATF6], and homologous protein [CHOP]), serine/threonine kinase 1 (Akt1), phosphatidylinositol 3‐kinase (PI3K), and peroxisome proliferator‐activated receptor γ (PPAR‐γ) were determined. Finally, histopathological analysis of the ovaries was evaluated. PCOS group exhibited increased ER stress, suppressing of PI3K/Akt1 and PPAR‐γ pathways, imbalance of sex hormonal profile, hyperglycemia, insulin resistance, dyslipidemia, increased profibrotic factors, and abnormal ovarian histopathological picture, while ADM treatment alleviated these disturbances occurring in the PCOS model. We concluded that ADM mitigated PCOS via attenuating the ER stress, in addition to activation of PI3K/Akt1 and PPAR‐γ pathways, its antioxidant, anti‐inflammatory, antiapoptotic, and antifibrotic properties.