bluuebunny/crossref_metadata_2025 huggingface dataset:
Reversible Dehalogenation in On‐Surface Aryl–Aryl Coupling
Authors: Stolz Samuel , Di Giovannantonio Marco , Urgel José I. , Sun Qiang , Kinikar Amogh , Borin Barin Gabriela , Bommert Max , Fasel Roman , Widmer Roland
Published: April 2020

In the emerging field of on‐surface synthesis, dehalogenative aryl–aryl coupling is unarguably the most prominent tool for the fabrication of covalently bonded carbon‐based nanomaterials. Despite its importance, the reaction kinetics are still poorly understood. Here we present a comprehensive temperature‐programmed x‐ray photoelectron spectroscopy investigation of reaction kinetics and energetics in the prototypical on‐surface dehalogenative polymerization of 4,4′′‐dibromo‐p‐terphenyl into poly(para‐phenylene) on two coinage metal surfaces, Cu(111) and Au(111). We find clear evidence for reversible dehalogenation on Au(111), which is inhibited on Cu(111) owing to the formation of organometallic intermediates. The incorporation of reversible dehalogenation in the reaction rate equations leads to excellent agreement with experimental data and allows extracting the relevant energy barriers. Our findings deepen the mechanistic understanding and call for its reassessment for surface‐confined aryl–aryl coupling on the most frequently used metal substrates.
Transient DNA‐Based Nanostructures Controlled by Redox Inputs
Authors: Del Grosso Erica , Prins Leonard J. , Ricci Francesco
Published: April 2020

Synthetic DNA has emerged as a powerful self‐assembled material for the engineering of nanoscale supramolecular devices and materials. Recently dissipative self‐assembly of DNA‐based supramolecular structures has emerged as a novel approach providing access to a new class of kinetically controlled DNA materials with unprecedented life‐like properties. So far, dissipative control has been achieved using DNA‐recognizing enzymes as energy dissipating units. Although highly efficient, enzymes pose limits in terms of long‐term stability and inhibition of enzyme activity by waste products. Herein, we provide the first example of kinetically controlled DNA nanostructures in which energy dissipation is achieved through a non‐enzymatic chemical reaction. More specifically, inspired by redox signalling, we employ redox cycles of disulfide‐bond formation/breakage to kinetically control the assembly and disassembly of tubular DNA nanostructures in a highly controllable and reversible fashion.
Magnetic Anisotropy in Divalent Lanthanide Compounds
Authors: Zhang Weibing , Muhtadi Almas , Iwahara Naoya , Ungur Liviu , Chibotaru Liviu F.
Published: April 2020

Complexes of trivalent lanthanides (Ln) are known to possess strong magnetic anisotropy, which enables them to be efficient single‐molecule magnets. High‐level ab initio calculations are reported for [LnO] (where Ln is terbium (Tb), dysprosium (Dy), or holmium (Ho)), which show that divalent lanthanides can exhibit equally strong magnetic anisotropy and magnetization blocking barriers. In particular, detailed calculations predict a multilevel magnetization blocking barrier exceeding 3000 K for a [DyO] complex deposited on a hexagonal boron nitride (h‐BN) surface, bringing the expected performance of single‐molecule magnets to a qualitatively new level compared to the current state‐of‐the art complexes.
Mechanical clamp stress on poly(vinyl chloride) infusion tubing: Impact on the surface degradation
Authors: Saunier Johanna , Marlière Christian , Dazzi Alexandre , Deniset‐Besseau Ariane , Yagoubi Najet
Published: April 2020

Several commercial infusion tubes made of plasticized poly(vinyl chloride) were shown to present a layer of bloomed species on their internal wall (lubricants and stabilizers), which are poorly soluble in water. During infusion, tubes are crushed and pinched to regulate the flow. The impact of mechanical stress on these layers infusion was studied. Device inner surfaces were characterized by atomic force microscopy in order to put into evidence surface degradations before and after infusion. This was correlated with a global and local infrared analysis. Because of the clamp stress, the deposits were damaged. Thus, injecting water into the damaged tubing increased the layer degradation. Roller clamp and pinch clamp may have very different effects on the inner layer morphology and degradation and this may be modulated by the initial layer morphology. Injecting water into clamp stressed tubing may increase the risk of detaching parts of the internal layer and be a supplementary factor of particulate contamination for the patient.
Rescue and relocation of benthic organisms during an urban‐port development project: Port of Manzanillo, case study
Authors: Liñán‐Rico Viridiana , Cruz‐Ramírez Angélica , Michel‐Morfín Jesús Emilio , Liñán‐Cabello Marco A.
Published: April 2020

The present study originated with the expansion of the boardwalk within the urban and port area of Manzanillo, México. Prior to civil works related to the placement of tetrapods, surveys of potential sites for the relocation of benthic organisms in alternative areas were carried out.

Based on indicators of the physical–chemical environment and biotic factors, nine areas with potential for relocation were evaluated. The areas of greatest potential were associated with environments located away from the influence of the port environment.

A total of 13,559 benthic organisms belonging to 68 species associated with three main substratum types (rocky, sandy, and mixed) were collected. There were no differences in the ecological indices between the three substrata.

The proximity of the collection area to the influence of port traffic and sources of pollution associated with the physical environment could be an important factor that affects ecological indices and the reduction in the abundance of some protected species and species of commercial interest.

The success of collection and relocation processes depends on minimizing possible errors, especially during transportation, when overcrowding, handling, and damage resulting from variable physico‐chemical conditions should be avoided.

Through a scheme of actions based on ecological principles, management actions, and civil engineering technology, it was possible to carry out mitigation, conservation, and habitat improvement actions in coastal marine environments exposed to anthropogenic impacts.
Contemporary use of balloon aortic valvuloplasty and evaluation of its success in different hemodynamic entities of severe aortic valve stenosis
Authors: Piayda Kerstin , Wimmer Anna Christina , Sievert Horst , Hellhammer Katharina , Afzal Shazia , Veulemans Verena , Jung Christian , Kelm Malte , Zeus Tobias
Published: April 2020

Objectives

To evaluate outcome assessment of percutaneous balloon aortic valvuloplasty (BAV) in different flow and gradient patterns of severe aortic stenosis (AS).

Background

The mean pressure gradient reduction after BAV is an often‐used surrogate parameter to evaluate procedural success. The definition of a successful BAV has not been evaluated in different subgroups of severe AS, which were introduced in the latest guidelines on the management of patients with valvular heart disease.

Methods

In this observational study, consecutive patients from July 2009 to March 2018 undergoing BAV were divided into normal‐flow high‐gradient (NFHG), low‐flow low‐gradient (LFLG), and paradoxical low‐flow low‐gradient (pLFLG) AS. Baseline characteristics, hemodynamic, and clinical information were collected and compared.

Results

One‐hundred‐fifty‐six patients were grouped into NFHG (n = 68, 43.5%), LFLG (n = 68, 43.5%), and pLFLG (n = 20, 12.8%) AS. Mean age of the study population was 81 years. Cardiogenic shock or refractory heart failure (46.8%) was the most common underlying reasons for BAV. Spearman correlation revealed that the mean pressure gradient reduction, determined by echocardiography, had a moderate correlation with the increase in the aortic valve area (AVA) in patients with NFHG AS (ρ: 0.529, p < .001) but showed no association in patients with LFLG (ρ: 0.017, p = .289) and pLFLG (ρ: 0.030, p = .889) AS. BAV as bridge to surgical or transcatheter aortic valve replacement was possible in 44.2% of patients, with no difference between groups (p = .070).

Conclusion

The mean pressure gradient reduction might be an adequate surrogate parameter for BAV success in patients with NFHG AS but is not suitable for patients with other hemodynamic entities.
Single Cobalt Atom Anchored Black Phosphorous Nanosheets as an Effective Cocatalyst Promotes Photocatalysis
Authors: Ren Xiaohui , Shi Li , Li Yunxiang , Song Shuang , Wang Qi , Luo Shunqin , Ren Long , Zhang Hongwei , Izumi Yasuo , Peng Xinsheng , Philo Davin , Ichihara Fumihiko , Ye Jinhua
Published: April 2020

Exploring novel cocatalysts with sufficient active sites and rapid photogenerated carrier separation remains challenge for boosting photocatalytic reactions. Recently, two‐dimensional (2D) black phosphorus (BP) has been developed and recognized to be an ideal platform for anchoring metal ions through lone pair electrons. Herein, we propose a new structure that cobalt atomically dispersed on BP nanosheets (BP−Co), and apply it as cocatalyst for photocatalytic H2 evolution and CO2 reduction under visible light (>420 nm) irradiation. Both scanning transmission electron microscope and X‐ray absorption near edge structure verified the existence of phosphorous‐coordinated Co sites. The interaction between Co and P brings greatly improvement on photocatalytic activities, and 18‐fold enhancement can be achieved on CdS when taking BP−Co as a noble‐metal‐free cocatalyst for H2 evolution, which is higher than that of Pt under the same conditions. Besides, BP−Co can also be used as an effective cocatalyst to promote photocatalytic CO2 reduction in the presence of photosensitizer [Ru(2, 2’‐bipyridy)3]Cl2 with a CO evolution rate of 88.6 μmol h−1, superior to those obtained from the state‐of‐the‐art cocatalysts. It is anticipated that the current work might provide basic understanding as well as new opportunities on 2D BP nanosheets for versatile photocatalytic reactions.
Model selection challenges with application to multivariate calibration updating methods
Authors: Gurung Anit , Kalivas John H.
Published: April 2020

An important issue in multivariate calibration including model updating methods with multiple tuning parameters is selection of final models. Model updating is an adaption process where models are updated from predicting in primary sample and measurement conditions to predict the analyte in new secondary conditions. A single process to select models (tuning parameter values) with satisfactory bias–variance trade‐offs across multiple data sets and modeling methods is challenging. This paper reports on evaluating the consistency of a collection of model quality measures to select models across five near‐infrared (NIR) data sets for three calibration updating approaches. The goal is to formulate a reliable model selection process that is nearly data and model updating method independent. Two of the three model updating approaches require primary and secondary analyte reference values, and the third only needs primary reference values (unlabeled relative to secondary). However, all model selection methods considered do require secondary samples with reference values. It is found that which evaluated model quality measure to use depends on the degree of spectral similarity between primary and secondary spectra as characterized by the indicator of spectral uniqueness measure developed in this paper. From the results presented, more work is needed to better characterize model selection dependency on model quality measures, number of samples and respective inherent compositions (data set‐dependent matrix effects), and tuning parameter ranges.
A Systematic Study of Coumarin–Tetrazine Light‐Up Probes for Bioorthogonal Fluorescence Imaging
Authors: Galeta Juraj , Dzijak Rastislav , Obořil Jan , Dračínský Martin , Vrabel Milan
Published: April 2020

Fluorescent probes that light‐up upon reaction with complementary bioorthogonal reagents are superior tools for no‐wash fluorogenic bioimaging applications. In this work, a thorough study is presented on a set of seventeen structurally diverse coumarin–tetrazine probes that produce fluorescent dyes with exceptional turn‐on ratios when reacted with trans‐cyclooctene (TCO) and bicyclononyne (BCN) dienophiles. In general, formation of the fully aromatic pyridazine‐containing dyes resulting from the reaction with BCN was found superior in terms of fluorogenicity. However, evaluation of the probes in cellular imaging experiments revealed that other factors, such as reaction kinetics and good cell permeability, prevail over the fluorescence turn‐on properties. The best compound identified in this study showed excellent performance in live cell‐labeling experiments and enabled no‐wash fluorogenic imaging on a timescale of seconds.
DDoS detection based on graph structure features and non‐negative matrix factorization
Authors: Jing Hengchang , Wang Jian
Published: April 2020

Distributed denial of service (DDoS) attacks are the most common and harmful attack in the field of network security, the purpose of this paper is to predict the occurrence of DDoS attacks quickly, accurately and effectively. In this paper, the characteristics of DDoS attacks are analyzed in detail, graph model is used to express the structural characteristics of traffic data between the victims and bots, at the same time, considering data characteristics of traffic itself, 11 characteristics are selected at last. The method of nonnegative matrix factorization (NMF) is adopted to mine the behavior pattern of DDoS attacks, and then the DDoS bots is detected by clustering according to the projection value of nodes on the behavior pattern. By extracting the attack behavior pattern, the attack behavior can be detected. Experimental results of real dataset verify the effectiveness and validity of the method.
Raman Optical Activity of Glucose and Sorbose in Extended Wavenumber Range
Authors: Palivec Vladimír , Michal Pavel , Kapitán Josef , Martinez‐Seara Hector , Bouř Petr
Published: April 2020

Raman optical activity (ROA) is pursued as a promising method for structural analyses of sugars in aqueous solutions. In the present study, experimental Raman and ROA spectra of glucose and sorbose obtained in an extended range (50–4000 cm−1) are interpreted using molecular dynamics and density functional theory, with the emphasis on CH stretching modes. A reasonable theoretical basis for spectral interpretation was obtained already at the harmonic level. Anharmonic corrections led to minor shifts of band positions (up to 25 cm−1) below 2000 cm−1, while the CH stretching bands shifted more, by ∼180 cm−1, and better reproduced the experiment. However, the anharmonicities could be included on a relatively low approximation level only, and they did not always improve the harmonic band shapes. The dependence on the structure and conformation shows that the CH stretching ROA spectral pattern is a sensitive marker useful in saccharide structure studies.
Corn yield and soil nitrogen following winter annual cover crops interseeded into soybean
Authors: Norris Robert , Chim Bee Khim , Evanylo Gregory , Reiter Mark , Thomason Wade
Published: April 2020

Nitrogen demand for corn (Zea mays L.) production is high, and winter annual cover crops (WCC) can be an alternative source of plant‐available N. Common corn–soybean [Glycine max (L.) Merr.] rotations in the Mid‐Atlantic region leave fields fallow after soybean, providing a niche for WCC. The objective of this research was to evaluate the effect of rye (Secale cereale L.), hairy vetch (Vicia villosa Roth subsp. Villosa), and rye–vetch mixture WCC interseeded into soybean on soil N, corn grain yield, and fertilizer N replacement from cover crops. Eight different field sites were seeded into standing soybeans in Virginia from 2012–2014. The experiment was a split‐plot design with WCC species as the main plot in a full factorial arrangement with N rate (0 or 45 kg N ha−1 as starter fertilization at planting, and sidedress rates of 0, 45, 90, 135, and 180 kg N ha−1) as subplots. Maximum corn grain yield following hairy vetch WCC was 0.7 and 0.6 Mg ha−1 higher than when following rye at 0 and 45 kg ha−1 starter N, respectively. At one site where hairy vetch biomass was >2 Mg ha−1, corn grain yield increased beyond levels attributable only to the addition of legume N. Instead of decreasing the sidedress N requirement, optimum N rates with hairy vetch were similar to other WCC, only with higher yields. Hairy vetch WCC generally resulted in higher soil N than other WCC at the V4 stage of corn, but no differences after corn harvest.
Calcium Carbide Looping System for Acetaldehyde Manufacturing from Virtually any Carbon Source
Authors: Rodygin Konstantin S. , Lotsman Kristina A. , Ananikov Valentine P.
Published: April 2020

A vinylation/devinylation looping system for acetaldehyde manufacturing was evaluated. Vinylation ofiso‐butanol with calcium carbide under solvent‐free conditions was combined with hydrolysis of the resultingiso‐butyl vinyl ether under slightly acidic conditions. Acetaldehyde produced by hydrolysis was collected from the reaction mixture by simple distillation, and the remaining alcohol was redirected to the vinylation step. All the inorganic co‐reagents can be looped as well, and the full sequence is totally sustainable. A complete acetaldehyde manufacturing cycle was proposed on the basis of the developed procedure. The cycle was fed with calcium carbide and produced the aldehyde as a single product in a total preparative yield of 97 %. No solvents, hydrocarbons, or metal catalysts were needed to maintain the cycle. As calcium carbide in principle can be synthesized from virtually any source of carbon, the developed technology represents an excellent example of biomass and waste conversion into a valuable industrial product.
Borophene and Boron Fullerene Materials in Hydrogen Storage: Opportunities and Challenges
Authors: Joseph Jithu , Sivasankarapillai Vishnu Sankar , Nikazar Sohrab , Shanawaz Muhammad Salman , Rahdar Abbas , Lin Han , Kyzas George Z.
Published: April 2020

Two‐dimensional materials have led to a leap forward in materials science research, especially in the fields of energy conversion and storage. Borophene and its spherical counterpart boron fullerene represent emerging materials that have attracted much attention in the whole area of advanced energy materials and technologies. Owing to their prominent features, such as electronic environment and geometry, borophene and boron fullerene have been used in versatile applications, such as supercapacitors, superconductors, anode materials for photochemical water splitting, and biosensors. Herein, one of the most promising applications/areas of hydrogen storage is discussed. Boron fullerenes have been considered and discussed for hydrogen‐storage applications, and recently borophene was also included in the list of materials with promising hydrogen‐storage properties. Studies focus mainly on doped borophene systems over pristine borophene due to enhanced features available upon decoration with metal atoms. This Review introduces very recent progress and novel paradigms with respect to both borophene derivatives and boron fullerene based systems reported for hydrogen storage, with a focus on the synthesis, physiochemical properties, hydrogen‐storage mechanism, and practical applications.
Redox‐Polymer‐Wired [NiFeSe] Hydrogenase Variants with Enhanced O2 Stability for Triple‐Protected High‐Current‐Density H2‐Oxidation Bioanodes
Authors: Ruff Adrian , Szczesny Julian , Vega Maria , Zacarias Sonia , Matias Pedro M. , Gounel Sébastien , Mano Nicolas , Pereira Inês A. C. , Schuhmann Wolfgang
Published: April 2020

Variants of the highly active [NiFeSe] hydrogenase from D. vulgaris Hildenborough that exhibit enhanced O2 tolerance were used as H2‐oxidation catalysts in H2/O2 biofuel cells. Two [NiFeSe] variants were electrically wired by means of low‐potential viologen‐modified redox polymers and evaluated with respect to H2‐oxidation and stability against O2 in the immobilized state. The two variants showed maximum current densities of (450±84) μA cm−2 for G491A and (476±172) μA cm−2 for variant G941S on glassy carbon electrodes and a higher O2 tolerance than the wild type. In addition, the polymer protected the enzyme from O2 damage and high‐potential inactivation, establishing a triple protection for the bioanode. The use of gas‐diffusion bioanodes provided current densities for H2‐oxidation of up to 6.3 mA cm−2. Combination of the gas‐diffusion bioanode with a bilirubin oxidase‐based gas‐diffusion O2‐reducing biocathode in a membrane‐free biofuel cell under anode‐limiting conditions showed unprecedented benchmark power densities of 4.4 mW cm−2 at 0.7 V and an open‐circuit voltage of 1.14 V even at moderate catalyst loadings, outperforming the previously reported system obtained with the [NiFeSe] wild type and the [NiFe] hydrogenase from D. vulgaris Miyazaki F.
An extendable single‐switch n‐cell boost converter with high voltage gain and low components stress for renewable energy
Authors: Zhang Guidong , Chen Haodong , Yu Shenglong , Zhang Bo , Chen Yanfeng , Iu Herbert , Zhang Yun
Published: April 2020

Boost converters have been widely employed in industrial applications, and cascading boost converters is a mature technique to realize ultrahigh voltage gains. However, the cascade structure inevitably increases the voltage stress of buffer capacitors, resulting in high costs and low energy efficiency. Targeting this issue, in this study, we propose a novel extendable single‐switch n‐cell boost converter (ESSnB), which utilizes the same number of components as the conventional positive output boost converter, but has lower buffer voltage stresses. Simulation and experimentation are conducted in this study, which verify the effectiveness and superiority of the proposed ESSnB over conventional boost converters.
3T‐FASDM: Linear discriminant analysis‐based three‐tier face anti‐spoofing detection model using support vector machine
Authors: Bakshi Aditya , Gupta Sunanda , Gupta Akhil , Tanwar Sudeep , Hsiao Kuei‐Fang
Published: April 2020

In recent years, to solve the problem of face spoofing, momentous work has been done in this field, but still, there is a need for establishing counter measures to the biometric spoofing attacks. Although trained and evaluated on different databases, impressive results have been achieved in existing face anti‐spoofing techniques, but biometric authentication is a very significant problem as imposters are using lots of reconstructed samples or fake synthetic material or structure that can be used for various attack purposes. For the first time, to the best of our knowledge, this paper explains the security for face anti‐spoofing detection using linear discriminant analysis and validates the results by calculating HTER and accuracy on different databases (i.e., REPLAY ATTACK and CASIA). The proposed model, that is, three‐tier face anti‐spoofing detection model (3T‐FASDM), is used for the detection of the fake biometric user and works well for real‐time applications. The proposed methods tested on a set of state‐of‐the‐art anti‐spoofing features for the face mode gives a very low degree of complexity as 26 general image quality measures are applied to differentiate among legitimate and imposter samples. The outcomes obtained from publically available data show that this technique has improved performance and accuracy by analyzing the HTER and machine learning classifiers that are helpful to differentiate among real and fake traits.
Study finds college, student preparedness to move online a mixed bag
Authors: Sutton Halley
Published: April 2020

A new survey of chief online learning officers giving an overview of the preparedness of campuses to move courses online has been released by Quality Matters and Eduventures. The survey recorded answers from 367 public, private, and for‐profit institutions nationwide, and included two‐year and four‐year institutions.
Crackdown on undisclosed foreign ties impacts higher ed
Authors: Kelly Sean R. , Cirilli Vincent C.
Published: April 2020

The U.S. Attorney's Office for the District of Massachusetts announced on Jan. 28 that Harvard University Professor Charles Lieber, Ph.D., was arrested and charged with a crime for allegedly lying to the U.S. government about his ties with China in connection with the application and receipt of federal grant money. This charge is the latest example of the U.S. government's crackdown on undisclosed university ties to China.
Noscapine, a possible drug candidate for attenuation of cytokine release associated with SARS‐CoV‐2
Authors: Ebrahimi Soltan A.
Published: April 2020

Successful treatment of viral infections has proven to be huge challenge for modern medicine with the most effective approach being prior vaccination. The problem with vaccination is the time it takes to develop an effective vaccine, validate its safety and manufacture it in large quantities. Facing Severe Acute Respiratory Syndrome Coronavirus‐2 (SARS‐CoV‐2), we simply do not have the time to develop the vaccine before thousands of people die. Therefore, any treatment which can decrease the severe symptoms due to lung damage may help attenuate mortality rates. Inactivation of ACE2 during virus fusion into the host cell may be one of the underlying reasons for intense immunological reaction seen in the lung tissue. This overreaction is probably mediated through the bradykinin receptor activation. Noscapine, a medication used for the treatment of cough, has been shown to inhibit bradykinin enhanced cough response in man. As it is already marketed in a number of countries as a cough medicine, even for children, a suitable formulation with all the required licenses is available that can be rapidly utilized in preliminary trials.
Butterfly richness and abundance along a gradient of imperviousness and the importance of matrix quality
Authors: Kurylo J. S. , Threlfall C. G. , Parris K. M. , Ossola A. , Williams N. S. G. , Evans K. L.
Published: April 2020

Heterogeneity in quantity and quality of resources provided in the urban matrix may mitigate adverse effects of urbanization intensity on the structure of biotic communities. To assess this we quantified the spatial variation in butterfly richness and abundance along an impervious surface gradient using three measures of urban matrix quality: floral resource availability and origin (native vs. exotic plants), tree cover, and the occurrence of remnant habitat patches. Butterfly richness and abundance were surveyed in 100 cells (500 × 500 m), selected using a random‐stratified sampling design, across a continuous gradient of imperviousness in Melbourne, Australia. Sampling occurred twice during the butterfly flight season. Occurrence data were analyzed using generalized linear models at local and mesoscales. Despite high sampling completeness, we did not detect 75% of species from the regional species pool in the urban area, suggesting that urbanization has caused a large proportion of the region's butterflies to become absent or extremely rare within Melbourne's metro‐area. Those species that do remain are largely very generalist in their choice of larval host plants. Butterfly species richness and abundance declined with increasing impervious surface cover and, contrary to evidence for other taxa, there was no evidence that richness peaked at intermediate levels of urbanization. Declines in abundance appeared to be more noticeable when impervious surface cover exceeded 25%, while richness declined linearly with increasing impervious surface cover. We find evidence that the quality of the urban matrix (floral resources and remnant vegetation) influenced butterfly richness and abundance although the effects were small. Total butterfly abundance responded negatively to exotic floral abundance early in the sampling season and positively to total floral abundance later in the sampling season. Butterfly species richness increased with tree cover. Negative impacts of increased urbanization intensity on butterfly species richness and abundance may be mitigated to some extent by improving the quality of the urban matrix by enhancing tree cover and the provision of floral resources, with some evidence that native plants are more effective.
Using Indigenous and Western knowledge systems for environmental risk assessment
Authors: Buell Mary-Claire , Ritchie Doran , Ryan Kathleen , Metcalfe Chris D.
Published: April 2020

Indigenous rights, knowledge, and value systems are linked inextricably to the lands, waters, and non‐human beings that form the environments of Indigenous Peoples. Across the globe, the rights of Indigenous peoples are being formally recognized and as a result, efforts are being made to include Indigenous Knowledge and value systems in environmental policy and decision making. Scientists and decision makers must not only recognize this reality, but also operationalize these efforts through meaningful changes to create space for the inclusion of Indigenous Knowledge, Indigenous values, and sovereignty within the current methods for scientific enquiry and the development of environmental policies. Professionals in the environmental field have a responsibility to ensure that their work has a positive impact on Indigenous Peoples and their environments. In this study, we explore the concept of consultation and informed consent through the lens of the development of environmental policy and decision making. We will discuss these concepts in the context of ecological risk assessment related to a case study focused on contaminated sediment in a harbor within the Great Lakes. We will demonstrate a process that deconstructs the current protocols for risk assessments at sites with localized pollutants in sediment and rebuilds them with elements that recognize both Western and Indigenous knowledge systems. This process includes collaborative fieldwork, relationship building, and informal and formal interviews with participants and community members. By utilizing such approaches, we were able to develop a risk assessment framework that recognizes the sovereignty of Indigenous peoples and promotes effective Nation‐to‐Nation decision making.
Access to evidence‐based care for eating disorders during the COVID‐19 crisis
Authors: Weissman Ruth S. , Bauer Stephanie , Thomas Jennifer J.
Published: April 2020

The COVID‐19 pandemic has forced an abrupt change in the delivery of clinical services, including for individuals with an eating disorder. We present this Virtual Issue as a resource for the eating disorder community to showcase research published in the International Journal of Eating Disorders that provides information on effective strategies to help address the challenges arising from COVID‐19‐related disruptions. Articles included describe original research or systematic reviews on obstacles to health services use and strategies to improve access to care; technological tools to provide or enhance interventions; patients' and clinicians' attitudes or perspectives on using digital tools for clinical care; factors influencing therapeutic alliance; and ideas for improving reach and uptake of digital interventions. We hope that readers will find ways to observe and record their own experiences during this global crisis; the experiences of people at risk for developing or exhibiting an eating disorder; and the experiences of those who care for people with an eating disorder. These lived experiences will be invaluable in formulating hypotheses for future studies in service of advancing the understanding of eating disorders and improving interventions and policies for reducing the burden of suffering attributable to eating disorders.
Neutralization of IL‐10 produced by B cells promotes protective immunity during persistent HCV infection in humanized mice
Authors: Liu Min , Chen Han‐Yu , Luo Liang , Wang Yaping , Zhang Dongli , Song Neng , Wang Fu‐Bing , Li Qiao , Zhang Xiao‐Lian , Pan Qin
Published: April 2020

Chronic HCV infection can lead to cirrhosis and is associated with increased mortality. Interleukin (IL)‐10‐producing B cells (B10 cells) are regulatory cells that suppress cellular immune responses. Here, we aimed to determine whether HCV induces B10 cells and assess the roles of the B10 cells during HCV infection. HCV‐induced B10 cells were enriched in CD19hi and CD1dhiCD5+ cell populations. HCV predominantly triggered the TLR2‐MyD88‐NF‐κB and AP‐1 signaling pathways to drive IL‐10 production by B cells. In a humanized murine model of persistent HCV infection, to neutralize IL‐10 produced by B10 cells, mice were treated with pcCD19scFv‐IL‐10R, which contains the genes coding the anti‐CD19 single‐chain variable fragment (CD19scFv) and the extracellular domain of IL‐10 receptor alpha chain (sIL‐10Ra). This treatment resulted in significant reduction of B10 cells in spleen and liver, increase of cytotoxic CD8+ T‐cell responses against HCV, and low viral loads in infected humanized mice. Our results indicate that targeting B10 cells via neutralization of IL‐10 may offer a novel strategy to enhance anti‐HCV immunotherapy.
Ce0.9Zr0.1O2Mixed Oxide Prepared by the Citrate Route: Impact of Synthesis Conditions on Physicochemical and Redox Properties
Authors: Anzorena Rosario Suarez , Toscani Lucía M. , Larrondo Susana A.
Published: April 2020

The aim of this work is to study the effect of the citric acid to metal molar ratio (CA/M) used in the citrate synthesis route on the structural, morphological and redox properties of CeO2‐ZrO2mixed oxides. The CA/M ratio strongly affects reducibility, crystallite size and texture. The increase in calcination temperature promotes sample crystallinity while nanometric sizes remain up to 1000 °C. H2‐TPR, in situ dispersive X‐ray absorption (DXAS) and Raman experiments show that samples calcined at 1000 °C exhibit a three‐step reduction kinetics and onset temperatures related to the initial oxygen vacancy content. Specific surface area and crystallite size influences the reduction profile mainly at low temperatures (≤ 600 °C) and high temperatures (> 600 °C) respectively. The increase of crystallite size with calcination temperature favors the diffusion of oxygen species from the bulk to the surface, enhancing reducibility and compensating for the drastic loss of surface area.
Synthesis and Characterization of N‐Heterocyclic Carbene Dithiocarbamate Platinum Complexes with Antitumoral Activity
Authors: Verron Raphaël , Achard Thierry , Seguin Cendrine , Fournel Sylvie , Bellemin‐Laponnaz Stéphane
Published: April 2020

A series of platinum(II) complexes bearing N‐heterocyclic carbene NHC of the type [(NHC)PtX(L)] where L is a dithiocarbamate ligand and X iodide were prepared and fully characterized. The molecular structure of one derivative was determined by single‐crystal X‐ray analyses confirming that the dithiocarbamate is acting as a bidentate ligand to the metal. All complexes demonstrated potent in vitro antiproliferative activities against cancer cells. Mechanistic investigations revealed that mitochondrial dysfunction and ROS (Reactive Oxygen Species) production were correlated with the cytotoxic process induced by these complexes.
Continuous Flow Organophosphorus Chemistry
Authors: Morodo Romain , Bianchi Pauline , Monbaliu Jean‐Christophe M.
Published: April 2020

Organophosphorus derivatives are widespread compounds that chemists find from the bench to the plant, with numerous daily life applications. Besides their common utility for a wide range of notorious reactions such as the Wittig and Horner‐Wadsworth‐Emmons olefinations, the Arbuzov reaction, the Staudinger reaction, the Mitsunobu reaction as well as ligands for a large variety of organometallic complexes, organophosphorus compounds have also found numerous applications as active pharmaceutical ingredients and agrochemicals. Some organophosphorus derivatives are also infamously known as Chemical Warfare Agents. Within the context of generalized adoption of new process technologies in the Chemistry Toolbox, this review intends to give an update on the most recent and significant advances in continuous flow organophosphorus chemistry. Selected examples in methodology, total synthesis and for the preparation of industrially relevant targets are discussed for illustrating the assets of flow chemistry.
Synthetic Studies towards CH‐Diazomethane Sulfonamides: a Novel Type of Diazo Reagents
Authors: Bubyrev Andrey , Dar'in Dmitry , Kantin Grigory , Krasavin Mikhail
Published: April 2020

Preparation of CH‐diazomethane sulfonamides has been developed for the first time. Their utility as a new type of diazo reagents was showcased in cycloaddition reactions with electron‐deficient alkynes and β‐nitro styrenes which delivered medicinally important pyrazole‐3‐sulfonamides in good to excellent yields.
Electrochemical Reduction of α‐Amino Allenylphosphonates to α‐Amino Allylphosphonates
Authors: Adler Pauline , de Oliveira Pedro , Rabasso Nicolas
Published: April 2020

α‐Amino allenylphosphonates are reduced to α‐amino allylphosphonates using electrochemical processes. The reduction products are obtained in moderate to good yields. Moreover, in the case of tosylamine compounds, we were pleased to take advantage of a simultaneous reduction and cleavage of the tosyl group from the nitrogen atom to access unprotected amino‐allylphosphonates. The mechanism of this reduction is also discussed.
Immunosensing of NT‐proBNP via Cu2+‐based MOFs Biolabeling and in situ Microliter‐droplet Anodic Stripping Voltammetry
Authors: Liu Huan , Chen Yingying , Cheng Yan , Xie Qingji , Liu Rushi , Yang Xiaoping
Published: April 2020

Immunoassay of amino‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) was conducted using Cu2+‐1,3,5‐benzenetricarboxylic acid metal‐organic frameworks (HKUST‐1 MOFs) as the secondary antibody label, and in situ microliter‐droplet anodic stripping voltammetry detection of Cu2+ in 0.1 M HNO3+1 M NaCl directly on the glassy carbon immunoelectrode. Electrochemical methods, quartz crystal microbalance, scanning electron microscopy and energy dispersive spectroscopy were employed for material and electrode characterizations. Under optimized conditions, the limit of detection (S/N=3) was 0.33 fg mL−1, and the analysis of NT‐proBNP in clinical serum samples returned good results.
Investigation of a two‐step device implementing magnetophoresis and dielectrophoresis for separation of circulating tumor cells from blood cells
Authors: Shamloo Amir , Yazdani Alireza , Saghafifar Fatemeh
Published: April 2020

Identifying tumor cells from a pool of other cells has always been an appealing topic for different purposes. The objective of this study is to discriminate circulating tumor cells (CTCs) from blood cells for diagnostic purposes in a novel microfluidic device using two active methods: magnetophoresis and dielectrophoresis. The most specific feature of this device is the differentiation of CTCs without labeling them in order to achieve a more reliable and less complicated method. This device was analyzed and evaluated using finite element method. Four cell lines are separated in this device containing red blood cells, platelets, white blood cells, and CTCs. Primarily, red blood cells and platelets, which constitute the largest part of a blood sample, are removed in the magnetophoresis section. Remaining cells enter the dielectrophoresis part and based on their inherent dielectric properties and diameters, final separation occurs. In each step, different parameters are examined to obtain the maximum purification. The results demonstrate the potential of different CTCs separation by changing the effective parameters in the designed device based on the inherent properties of the cells.
In situ studies of the degradation mechanisms of perovskite solar cells
Authors: Kundu Soumya , Kelly Timothy L.
Published: April 2020

The last decade has seen an extraordinary rise in the performance of perovskite solar cells (PSCs). State‐of‐the‐art devices now have efficiencies of over 25%, putting them on par with the best silicon solar cells. Yet despite their impressive performance, their longevity lags behind that of conventional silicon technology. Environmental factors like moisture, heat, and light can all adversely affect PSC performance and limit device lifetime. Systematically elucidating and eliminating PSC degradation pathways will be critical to the success of this technology. In situ techniques provide powerful tools to this end, as they allow structural, compositional, morphological, and optoelectronic changes to be tracked in real‐time. Because they follow a single film or device over the course of the degradation process, they can help eliminate the statistical variation that negatively affects many studies. Here we provide an overview of perovskite degradation processes, with an emphasis on in situ studies.

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Design of automatic pressurizing device of hydraulic support initial force
Authors: Cao Lianmin , Xu Guotai , Su Guoxiu , Cui Jiulong , Cai Yong , Cao Huiling
Published: April 2020

This paper brings forth a kind of automatic pressurizing device which can resolve the problem of poor hydraulic support setting load directly without modifying the original hydraulic system excessively. On the basis of the control loop that is designed according to working requirements and conditions to realize automatic pressurization of stand column system, it is divided into pressurizing structure and auxiliary structure. Reserved liquid opening and unit design are used to design the automatic pressurizing device from the principle perspective, and it is also made associated with all units reasonably by improving the details. The automatic pressurizing device combines machinery and hydraulic pressure so that all structural units can finish the expected action and coordinate mutually under the effect of emulsion in order to finally realize the overall function of automatic and fast pressurization. On the basis of the simulated analysis of AMESim hydraulic simulation platform on the control loop and lifting support system loop of support stand column, the working performance of automatic pressurizing device and dynamic characteristics of control loop are simulated. The result after comparing and analyzing the simulation curve and site installation test of underground ZY12000/28/63D support finally shows that the device is able to enhance the setting load to above 30 MPa, which is basically the same with simulation result. It demonstrates that the design of automatic pressurizing device conforms to the expected pressurization requirements and the pressurization effect is significant.
Security overhead of random linear network coding in multicast relay networks
Authors: Maboudi Behnaz , Pahlevani Peyman
Published: April 2020

The relays in random linear network coding (RLNC) approach recode and transmit the coded packets to boost the performance against packet loss. However, this can endanger the system to pollution attacks, which can be eliminated by Homomorphic message authentication code (HMAC). Cache coding limits RLNC by coding only the decoded packets in the relays. In the other words, the relay node in cache coding first decodes the coded packets, then recodes and protects them by a MAC‐based scheme that allows the next hop to discover the pollution in the network. This study provides analytical models for cache coding and RLNC to compare their communication overhead. First, we approximate the number of transmissions in a network consisting several relays. The approximation models are for the cases of a few and large number of relays. Then, we validate our analysis using simulation results and illustrate that cache coding can eliminate the pollution attack issue of RLNC with only a slight increase in the bandwidth usage when there are no malicious nodes in the network. Moreover, we conclude that it is more beneficial to employ the cache coding approach at the presence of malicious nodes in the
network.
Aging mechanisms—A perspective mostly from Drosophila
Authors: Tsurumi Amy , Li Willis X.
Published: April 2020

A mechanistic understanding of the natural aging process, which is distinct from aging‐related disease mechanisms, is essential for developing interventions to extend lifespan or healthspan. Here, we discuss current trends in aging research and address conceptual and experimental challenges in the field. We examine various molecular markers implicated in aging with an emphasis on the role of heterochromatin and epigenetic changes. Studies in model organisms have been advantageous in elucidating conserved genetic and epigenetic mechanisms and assessing interventions that affect aging. We highlight the use of Drosophila, which allows controlled studies for evaluating genetic and environmental contributors to aging conveniently. Finally, we propose the use of novel methodologies and future strategies using Drosophila in aging research.
The Barts Explanatory Model Inventory for Dementia: An item reduction approach based on responses from South Asian communities
Authors: Kampanellou Eleni , Wilberforce Mark , Worden Angela , Giebel Clarissa , Challis David , Bhui Kamaldeep
Published: April 2020

Background

Cultural differences in how the symptoms, causes, consequences, and treatments of dementia are understood and interpreted by South Asian people are a commonly expressed reason for late‐ or nonuse of mental health and care services. However, systematic collection of information on South Asian perceptions of dementia is hindered by a lack of appropriate instrumentation.

Objectives

To produce a shortened version of the Barts Explanatory Model Inventory for Dementia (BEMI‐D) schedule.

Methods

A two stage item reduction approach was employed first using multidimensional scaling categorizing items as core, intermediate, or outlier. Then, item review was undertaken using three criteria: literature importance, clinical face validity, and sub‐group prevalence. The analysis followed a nonmetric multidimensional scaling method based on a two‐way proximity matrix.

Results

The original BEMI‐D had 197 items allocated to four checklists: symptoms, causes, consequences, and treatments. The two stage item reduction approach resulted in the removal of 75 items. These reductions were achieved across all four checklists in relatively equal proportions. There was no evidence of substantive content loss in the revised schedule. The reduced version of the schedule comprises 122 items.

Conclusions

A condensed version of the BEMI‐D is more efficient as an assessment schedule that captures the culturally diverse perceptions of memory problems for South Asians offering a balanced trade‐off between feasibility of use and content validity.
Taxes on unhealthy food and externalities in the parental choice of children's diet
Authors: Kalamov Zarko , Runkel Marco
Published: April 2020

This study examines whether taxes on unhealthy food are suitable for internalizing intergenerational externalities inflicted by parents when they decide on their children's diet. In an overlapping generations (OLG) model with an imperfectly altruistic parent, the optimal steady‐state tax rate on unhealthy food is strictly positive. However, it is only second‐best because, in addition to reducing unhealthy consumption by the child, it distorts the parent's unhealthy consumption. Surprisingly, the optimal tax may underinternalize or overinternalize the marginal damage.