bluuebunny/crossref_metadata_2025 huggingface dataset:
Access or Ownership? The effect of car attributes and collective psychological ownership on the preference for car subscription services
Authors: Szamatowicz Marcin , Paundra Joshua
Published: May 2019

Alternative transportation services for urban commuters expand with car subscription services. Car subscription services give drivers access to cars without ownership for a relatively longer time period (e.g., months) than other sharing economy transportation services. Based on a mix of between- and within-subject design online experiment involving 274 participants, this study investigates traditional and upcoming subscribed car features namely, mileage limit, price, self-driving capability, advanced safety systems, and the moderating influence of collective psychological ownership of these features on people’s preference for car subscription services. The results suggest that these features significantly impact people’s preference toward this service. Collective psychological ownership was found to moderate the influence of self-driving capability and advance safety systems on people’s preference for car subscription services. Individuals with high collective psychological ownership preferred subscription cars with self-driving capability and were more concerned with the lack of advanced safety systems in a subscription car. Car subscription companies need to consider traditional (price and mileage limit), and upcoming features (self-driving capability and advance safety systems) when offering their services. More importantly, the moderating influence of collective psychological ownership on these features means that car subscription companies should account for people’s psychological disposition when considering additional car features.
A valve-like mechanism controls desensitization of functional mammalian isoforms of acid-sensing ion channels
Authors: Wu Yangyu , Chen Zhuyuan , Canessa Cecilia M
Published: May 2019

ASICs are proton-gated sodium channels expressed in neurons. Structures of chicken ASIC1 in three conformations have advanced understanding of proton-mediated gating; however, a molecular mechanism describing desensitization from open and pre-open states (steady-state desensitization or SSD) remains elusive. A distinct feature of the desensitized state is an 180o rotation of residues L415 and N416 in the β11- β12 linker that was proposed to mediate desensitization; whether and how it translates into desensitization has not been explored yet. Using electrophysiological measurements of injected Xenopus oocytes, we show that Q276 in β9 strand works with L415 and N416 to mediate both types of desensitization in ASIC1a, ASIC2a and ASIC3. Q276 functions as a valve that enables or restricts rotation of L415 and N416 to keep the linker compressed, its relaxation lengthens openings and leads to sustained currents. At low proton concentrations, the proposed mechanism working in only one of three subunits of the channel is sufficient to induce SSD.
How can we augment the few that remain? Using stable population dynamics to aid reintroduction planning of an iteroparous species
Authors: Hanley Brenda J. , Bunting Elizabeth M. , Schuler Krysten L.
Published: May 2019

Restoration of depleted populations is an important method in biological conservation. Reintroduction strategies frequently aim to restore stable, increasing, self-sustaining populations. Knowledge of asymptotic system dynamics may provide advantage in selecting reintroduction strategies. We introduce interactive software that is designed to identify strategies for release of females that are immediately aligned with stable population dynamics from species represented by 2-, 3-, 4-, and 5-stage life history strategies. The software allows managers to input a matrix of interest, the desired number of breeding females, and the desired management timeline, and calls upon stable population theory to give release strategies that are in concert with both stable population status and the management goals. We demonstrate how the software can aid in assessing various strategies ahead of a hypothetical restoration. For the purpose of demonstration of the tool only, we use published vital rates of an ungulate species, but remark that the selection of species for demonstration is not central to the use of this tool. Adaption of this tool to real-life restorations of any 2-, 3-, 4-, or 5-stage iteroparous species may aid in understanding how to minimize undesirable recovery complications that may naturally arise from transient population dynamics. The software is freely available at: https//cwhl.vet.cornell.edu/tools/stapopd.
Galantamine plasma concentration and cognitive response in Alzheimer’s disease
Authors: Lin Yi-Ting , Chou Mei-Chuan , Wu Shyh-Jong , Yang Yuan-Han
Published: May 2019

Background

Galantamine has been approved for the treatment of Alzheimer’s disease (AD). However, there are few studies which have reported the association between cognitive responses and galantamine plasma concentration. The aim of this study was to determine the correlation between galantamine plasma concentration and the subsequent cognitive response following treatment in AD patients.

Methods

AD sufferers who continuously took 8 mg/d galantamine for at least 6 months without previous exposure to other kinds of AChEI such as donepezil, rivastigmine, or memantine were included in this cohort study. The assessments included the Mini Mental Status Examination (MMSE), Clinical Dementia Rating Scale (CDR) and the Cognitive Assessment Screening Instrument (CASI). Each subdomain of the CASI assessment was conducted at baseline and after 6 months of galantamine. The plasma concentrations of galantamine were measured by capillary electrophoresis after 6 months of the treatment. Logistic regression was performed to adjust for age, gender, apolipoprotein E ε4 genotype status, and baseline score to investigate the association between galantamine plasma concentrations and the cognitive response.

Results

The total sample consisted of 33 clinically diagnosed AD patients taking galantamine 8 mg/d for 6 months. There was no linear correlation between galantamine concentration and cognitive response in patients. However, 22 patients were responsive to the treatment in the long-term memory domain. In CASI subset domain, concentration improved during the 6 months follow up.

Conclusions

In the limited samples study, galantamine mostly benefitted the cognitive domain of long-term memory. The benefits were not related to the galantamine plasma concentration. Objective intra-individual evaluation of therapeutic response should be encouraged.
Ensino superior e desenvolvimento regional: o exemplo da Universidade Estadual da Paraíba
Authors: Albino Luciano
Published: May 2019

Este artigo tem o objetivo de analisar a função social da universidade como indutora de desenvolvimento. No estado da Paraíba, as ações acadêmicas e o corpo orçamentário e financeiro de sua Universidade Estadual dinamizam a economia própria de seu universo de atuação. Para tal estudo, do ponto de vista metodológico, foi realizada uma investigação bibliográfica do material disponível em sua Biblioteca Central a respeito do que havia sido publicado sobre a história da UEPB. A partir do material construído sobre a universidade, com 50 anos completados em 2016, tornou-se possível identificar motivações e projetos que propiciaram a concretização de uma instituição de ensino superior no interior da Paraíba. Em termos contemporâneos, buscou-se atualizar sua história segundo dados condizentes com o tamanho da instituição, a partir do que há disponível na Pró-Reitoria de Planejamento e Orçamento. Como resultado, conclui-se que a UEPB se estabelece em três grandes orientações: formação de professores, estudos sobre o semiárido e tecnologias aplicadas à saúde. Possui vocação para formar pobres, filhos de trabalhadores e trabalhadoras do campo e de pequenos municípios do interior do Nordeste e com forte participação na economia do estado da Paraíba.
Políticas públicas para o desenvolvimento da Economia Solidária no Nordeste brasileiro
Authors: Serafim Vitoria Maria
Published: May 2019

Diante do caráter socioeconômico do associativismo e cooperativismo, inúmeras políticas públicas são desenvolvidas para promovê-las com o intuito de combater a pobreza e a exclusão social. No município de Ibicuitinga, Ceará, encontra-se a Associação de Aquicultores de Ibicuitinga, constituída por 46 membros, contemplada por políticas públicas para incentivar e desenvolver o associativismo da aquicultura. Este trabalho buscou verificar a efetividade das políticas públicas voltadas para o incentivo e o desenvolvimento do associativismo da aquicultura do citado município na percepção dos beneficiados. Para tanto utilizou-se uma metodologia qualitativa, baseada em entrevista semiestruturada, cujos dados foram tratados através de análise de conteúdo. Como resultados, concluiu-se que as políticas públicas de incentivo ao associativismo (seguridade social, habitação e acesso ao crédito) são eficazes no alcance de seus objetivos, enquanto as políticas públicas que visam contribuir para o desenvolvimento (educação, capacitação) precisam ser revistas, uma vez que não têm obtido êxito no cumprimento de seus propósitos.
Heavy Metal Burden and Evaluation of Human Health Risks in Tomato Fruits Cultivated in Katsina State, North West Nigeria
Authors: Yaradua A. I. , Alhassan A. J. , Nasir A. , Bala M. , Usman A. , Idi A. , Muhammad I. U. , Yaro S. A. , Muhammad I.
Published: May 2019

This study was conducted to determine the heavy metals concentration in Tomato fruits cultivated in Katsina State Nigeria. The objectives were mainly to detect the presence of heavy metals in the cultivated Tomato fruits in the study area, compare the concentration of heavy metals in samples in relation to the permissible limits specified by WHO/FAO/USEPA Standards. Samples of cultivated tomato fruits were collected in the year 2017 from the selected areas. Analysis for the concentration of these heavy metals; Cr, Cd, Fe, Ni, Mn, Pb and Zn was conducted by the use of AAS (by Atomic Absorption Spectrophotometry) method. The health risks to the local inhabitants from the consumption of the samples were evaluated based on the Target Hazard Quotient (THQ). The possibility of cancer risks in the samples through intake of carcinogenic heavy metals was estimated using the Incremental Lifetime Cancer Risk (ILCR). Results from this study has shown that with the exception of the mean values for the heavy metal Pb (1.171–1.21 mg/kg), the mean concentration (mg/kg) range values of Zn (0.558- 1.851), Fe (0.880–1.181), Mn (0.458-0.671) and Cd (0.054-0.062) were below the WHO/FAO maximum permissive limits. The results have indicated that the estimated daily intake (EDI) of the heavy metals were lower than the tolerable daily intake limit set by the USEPA in all the samples. All the studied tomato fruits showed the risk level (HI < 1). Risk level of Target Hazard Quotient (THQ < 1) was observed for all the evaluated heavy metals for both adults and children. The THQ for the samples were in the decreasing order Mn>Zn>Pb>Fe>Cd, for all the tomato fruits respectively. ILCR for Cd violated the threshold risk limit (>10−4) and ILCR for Pb reached the moderate risk limit (>10−3) in all the studied samples in adults, While in children ILCR for both Pb and Cd violated the risk. The sampling area trend of risk for developing cancer as a result of consuming the studied samples showed in decreasing order: Daura senatorial zone > Funtua senatorial zone> Katsina senatorial zone for both adult and children.  Cumulative cancer risk (∑ILCR) of all the studied tomato fruits reached the moderate risk limit (>10−3) in adults, while in children it is above the moderate risk limit (>10−2). The study suggests that consumption of the studied tomato fruits in Katsina state is of public health concern as they may contribute to the population cancer burden.
State of Health Facilities in Communities Designated for Community-Based Health Insurance Scheme in Nigeria: A Case Study of Kwara and Ogun States
Authors: Raheem T. Y. , Adewale B. , Adeneye A. K. , Musa A. Z. , Ezeugwu S. M. C. , Yisau J. , Afocha E. , Sulyman M. A. , Adewoyin O. O. , Olayemi M. , Ayeni O. C. , Akinremi A. O. , Runsewe K. , Mafe M. A. , Ujah I. A. O.
Published: May 2019

Background: Nigerian Government established National Health Insurance Scheme (NHIS) including Community Based Health Insurance Scheme (CBHIS) to reduce out-of-pocket health expenses of enrollees, strengthen and ensure access to quality healthcare services. The functionality of the schemes however, revolves round health facilities being able to meet the expectation of the enrollees.

Study Objectives: The study assessed the adequacy of the designated health facilities in offering quality healthcare services to the enrollees or potential enrollees under the CBHIS, and to identify likely challenges.

Study Design: This is part of a larger prospective cross-sectional study that assessed the implementation of the Community-Based Health Insurance Scheme (CBHIS) in selected local government areas of Kwara in the north central and Ogun in the South Western part of Nigeria.

Place and Duration of the Study: Health facilities of selected wards from two Local Government Areas in Kwara and Ogun States were assessed between February and May 2015.

Methods: Semi-structured questionnaires and health facility assessment checklist were used to assess services rendered, storage of drugs and the vaccines, manpower, training opportunities, available infrastructures and perceived challenges to smooth operation of health facilities designated for CBHIS.

Results: A total of twenty designated health facilities were visited and assessed (Seventeen public and three private). Services claimed to be available at the facilities included clinical, nursing, pharmaceutical and laboratory services. The assessment showed inadequacy of some critical human resources for health. Seventeen of the 20 health facilities (85%) had evidence of recent renovation while 3 (15%) had no evidence of renovation. Twelve (60%) had backup supply of electricity from generator or solar panel. Other challenges that could impede quality healthcare service delivery under the CBHIS were identified.

Conclusion: The study showed that inadequate personnel, paucity of training opportunities for health workers, poor infrastructures (lack of ambulance services, poor electricity supply and lack of portable water supply) were the main challenges impeding delivery of quality healthcare services to the CBHIS enrollees patronizing the studied facilities.
Evaluation of Antibacterial Activity of Zobo and Bay Leaf Extracts on Enteropathogenic Bacteria
Authors: Wemedo S. A. , Akani N. P. , Amadiali A. D.
Published: May 2019

Aim: The antibacterial activity of Bay leaf (Laurus nobilis L.) and Zobo leaf (Hibiscus sabdariffa L.) extracts on enteropathogenic bacteria was investigated.

Study Design: The study utilized well in agar diffusion to investigate the antimicrobial properties of the extracts.

Place and Duration of Study: Department of Microbiology, Rivers State University and the study was carried out in August, 2018 to October, 2018.

Methodology: Faecal samples were collected from a medical laboratory and inoculated on eosin methylene blue and mannitol salt agar plates for Escherichia coli and Staphylococcus aureus using standard microbiological techniques. The bacterial isolates were subjected to biochemical and molecular (PCR) identification so as to ascertain the distinctiveness of the isolates. Hot water and absolute alcohol were used as the extracting solvents. Concentrations of the extracted solvents was tested against E. coli and S. aureus using the well in agar method.

Results: The result showed that both hot aqueous and alcoholic extracts of Bay leaf showed no sensitivity against the tested bacteria, whereas the extracts of hot dry aqueous and alcohol of Zobo leaf showed remarkable zones of inhibition against the tested bacteria. The zones of inhibition in the dry hot aqueous extract of zobo leaf with concentrations of 0.25 µg/mL, 0.125 µg/mL and 0.063 µg/mL were 31.3±0.1, 25.6±1.2 and 10.0±0.0, respectively. The minimal inhibitory concentration of the dry hot aqueous of zobo extract was observed at 0.063 µg/mL for E. coli, while zones of inhibition of 33.3±0.0, 30.1±0.3, 17.2±1.0 and 15.0±0.1 mm were recorded from the dry alcoholic extract of zobo leaf on E. coli given similar concentrations and the MIC was observed at the 0.031 µg/mL concentration. The result also showed that out of the four concentrations of the dry hot aqueous extract, only the 0.25 µg/mL concentration was able to show 14.2±0.0 mm inhibition on S. aureus, while the concentrations of 0.25 µg/ml and 0.125 µg/mL were the only two concentrations of the dry alcohol that showed levels of sensitivity with zone diameters of 29.3±1.0 and 25.2±0.0, respectively.

Conclusion: The plant extracts of zobo leaves which displayed remarkable activity at fairly-low concentrations could be recommended for use against similar bacteria. Thus, investigation and adoption of plant extracts in modern medicine should be encouraged as this may be the break through needed to combat the ever-increasing resistance to commonly used antibiotics.
Canonical Correlation between Soil Attributes and Foliar of Conilon Coffee Trees
Authors: Fonseca Abel Souza da , Lima Julião Soares de Souza , Dardengo Maria Christina Junger Delôgo , Silva Samuel De Assis , Xavier Alexandre Candido
Published: May 2019

The nutritional status of the coffee tree is influenced by the concentration of nutrients in the soil of the growing area. The objective of this work was to evaluate, using canonical correlation, the linear relationships between chemical attributes of soil and nutrients of leaf tissues in seminal coffee. The work was developed in a commercial crop located in the municipality of Cachoeiro de Itapemirim, the southern region of the state of Espírito Santo. In the crop, an irregular sampling mesh was constructed, totalling 80 georeferenced points. The canonical correlation analysis was performed considering the original data observed in two consecutive conilon coffee harvests, 2015/16 and 2016/17, to verify the associations between a (dependent) group formed by foliar nutrients (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn) and an independent group formed by soil chemical attributes (pH, Ca, Al, K, S, P, Cu, Fe, Mn and Zn). Even if nutrients are available, that is, available in a satisfactory amount in the soil, it can happen that it does not reach the leaf tissue, resulting in a deficiency for some nutrients. There was a direct relationship between the concentration of K in the leaf tissue and K in the soil in the two harvests. Other soil attributes, such as Organic Matter, Fe, Mn, and S, also influenced this relationship, showing that the soil attributes in the independent group interact together on the nutrients in the leaf tissue. There is an inverse relationship between the concentrations of K in the leaf tissue and the Mn in the soil in the two harvests, showing that the excess of Mn in the soil is influencing the K deficiency in the leaf tissue.
Crystal structure of the unoccupied murine urokinase‐type plasminogen activator receptor (uPAR) reveals a tightly packed DII–DIII unit
Authors: Liu Min , Lin Lin , Høyer‐Hansen Gunilla , Ploug Michael , Li Hanlin , Jiang Longguang , Yuan Cai , Li Jinyu , Huang Mingdong
Published: May 2019

The urokinase‐type plasminogen activator receptor (uPAR) is a cell surface receptor that is capable of binding to a range of extracellular proteins and triggering a series of proteolytic and signaling events. Previous structural studies of uPAR with its ligands uPA and vitronectin revealed that its three domains (DI, DII, and DIII) form a large hydrophobic cavity to accommodate uPA. In the present study, the structure of unoccupied murine uPAR (muPAR) is determined. The structure of DII and DIII of muPAR is well defined and forms a compact globular unit, while DI could not be traced. Molecular dynamic simulations further confirm the rigid binding interface between DII and DIII. This study shows overall structural flexibility of uPAR in the absence of uPA.
T‐S fuzzy model–based adaptive repetitive learning consensus control of high‐order multiagent systems with imprecise communication topology structure
Authors: Chen Jiaxi , Li Junmin , Li Jinsha , He Chao
Published: May 2019

This paper addresses the consensus problem for high‐order nonlinear multiagent systems with imprecise communication topology structure (ICTS) and unknown periodic time‐varying parameters. Takagi‐Sugeno fuzzy models are used to portray the ICTS. By using the reparameterization technique, the repetitive learning control protocol is presented to guarantee that all the followers can track the leader asymptotically under the condition that the ICTS is fuzzy union connected. The information of the leader is known to a small portion of following agents; an auxiliary control term is presented for each follower agent to handle leader's dynamics. The consensus performance is analyzed via Lyapunov stability theory. Furthermore, the proposed protocol is further promoted to solve the formation control problem. Finally, the validity of the proposed methods are verified by two simulation examples.
A Cost‐Effective Mixed Matrix Polyethylene Porous Membrane for Long‐Cycle High Power Density Alkaline Zinc‐Based Flow Batteries
Authors: Chang Nana , Yin Yanbin , Yue Meng , Yuan Zhizhang , Zhang Huamin , Lai Qinzhi , Li Xianfeng
Published: May 2019

Alkaline zinc‐based flow batteries (ZFBs) have received considerable interest for renewable energy storage due to their attractive features of low cost and high energy density. However, a membrane with high stability, high selectivity, and high ion conductivity is in urgent need. Herein, an economical mixed matrix membrane with highly anti‐alkali microporous hollow spheres (denoted as DM‐HM) is developed in this work. With excellent chemical and mechanical stability, DM‐HM can achieve a high area capacity of 100 mA h cm−2 for carbon felt (CF)||Zn@CF symmetrical flow battery, and thereby exhibits 500 stable cycles with a coulombic efficiency of 98.6% and an energy efficiency of 88.3% at 80 mA cm−2 for alkaline zinc–iron flow battery. Additionally, with 44 wt% of hollow spheres inside matrix, DM‐HM can dramatically shorten the ion transport pathway and results in a very high power density battery. A kilowatt stack assembled with DM‐HM shows a very impressive performance, further confirming the practicability of this scalable mixed matrix membrane for alkaline ZFBs.
Microparticle‐Based Soft Electronic Devices: Toward One‐Particle/One‐Pixel
Authors: Hwang Hyejin , Jeong Unyong
Published: May 2019

While microparticle (MP) assemblies have long attracted academic interest, few practical applications of assembled MPs have been achieved because of technological difficulties related to MP synthesis, MP position registration, and the absence of device concepts. The precise positioning of functional MPs in a proper stencil can produce flexible/stretchable electronic devices, even when the MPs themselves are rigid. In recent years, remarkable progress has been made in the programmable position registration of MPs, production of functional MPs, and concepts for MP‐based, pixel‐type electronic devices. This progress report reviews the recent technological advances in MP assembly and discusses the technological challenges preventing the realization of the one‐particle/one‐pixel concept.
Mimicking Molecular Chaperones to Regulate Protein Folding
Authors: Ma Fei‐He , Li Chang , Liu Yang , Shi Linqi
Published: May 2019

Folding and unfolding are essential ways for a protein to regulate its biological activity. The misfolding of proteins usually reduces or completely compromises their biological functions, which eventually causes a wide range of diseases including neurodegeneration diseases, type II diabetes, and cancers. Therefore, materials that can regulate protein folding and maintain proteostasis are of significant biological and medical importance. In living organisms, molecular chaperones are a family of proteins that maintain proteostasis by interacting with, stabilizing, and repairing various non‐native proteins. In the past few decades, efforts have been made to create artificial systems to mimic the structure and biological functions of nature chaperonins. Herein, recent progress in the design and construction of materials that mimic different kinds of natural molecular chaperones is summarized. The fabrication methods, construction rules, and working mechanisms of these artificial chaperone systems are described. The application of these materials in enhancing the thermal stability of proteins, assisting de novo folding of proteins, and preventing formation of toxic protein aggregates is also highlighted and explored. Finally, the challenges and potential in the field of chaperone‐mimetic materials are discussed.
Direct Imaging of Current‐Induced Transformation of a Perovskite/Electrode Interface
Authors: Drozdov Mikhail N. , Yunin Pavel A. , Travkin Vlad V. , Koptyaev Andrey I. , Pakhomov Georgy L.
Published: May 2019

Formamidinium‐lead‐iodide (FAPbI3) perovskite films are subjected to a long‐term action of the constant electrical current in the dark, using planar vacuum‐deposited gold electrodes. The current‐induced transformation is monitored by the time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) mapping complemented by microscopic, spectroscopic methods, and X‐ray diffraction. The migration of chemical species inside the lateral interelectrode gap is clearly visualized by ToF‐SIMS. Those species correspond to both electrode material and perovskite itself, so that the perovskite/electrode interface becomes disrupted. As a result, the interelectrode gap shrinks, which is reflected in the surface images.
Morphology Phase Diagram of Slot‐Die Printed TiO2Films Based on Sol–Gel Synthesis
Authors: Li Nian , Song Lin , Bießmann Lorenz , Xia Senlin , Ohm Wiebke , Brett Calvin J. , Hadjixenophontos Efi , Schmitz Guido , Roth Stephan V. , Müller‐Buschbaum Peter
Published: May 2019

Mesoporous titania films with tailored nanostructures are fabricated via slot‐die printing, which is a simple and cost‐effective thin‐film deposition technique with the possibility of a large‐scale manufacturing. Based on this technique, which is favorable in industry, TiO2films possess the similar advantage with polymer semiconducting devices like ease of large‐scale production. The titania morphologies, including foam‐like nanostructures, nanowire aggregates, collapsed vesicles and nanogranules, are achieved via a so‐called block‐copolymer‐assisted sol–gel synthesis. By adjusting the weight fraction of reactants, the ternary morphology phase diagram of the printed titania films is probed after template removal. The surface and inner morphology evolutions are explored with scanning electron microscopy and grazing incidence small‐angle X‐ray scattering, respectively. Special focus is set on foam‐like titania nanostructures as they are of especial interest for, e.g., solar cell applications. At a low weight fraction of the titania precursor titanium(IV)isopropoxide (TTIP), foam‐like titania films are achieved, which exhibit a high uniformity and possess large pore sizes. The anatase phase of the highly crystalline titania films is verified with X‐ray diffraction and transmission electron microscopy.
Dehydrative Cross‐Coupling and Related Reactions between Alcohols (C−OH) and P(O)−H Compounds for C−P Bond Formation
Authors: Chen Long , Zou Yun‐Xiang , Liu Xiao‐Yan , Gou Xiao‐Jun
Published: May 2019

In recent decades, reactions of inexpensive and abundantly available alcohols (C−OH) with nucleophilic P(O)−H compounds, leading to the construction of C−P bonds, have emerged as one of the most efficient strategies as it is an atom‐economical and environmental benign approach with water as the only by‐product. Various organophosphorus compounds bearing C(sp3)−P, C(aryl)−P and C(alkenyl)−P bonds have been achieved via this direct dehydrative cross‐couplings under Brønsted or Lewis acid catalysis. This review article aims to summarize the recent advances in such dehydrative and related C−P bond forming strategies, to briefly discuss the reaction mechanisms and challenges, and to outline synthetic opportunities that are still open.

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Systematic Study of the Effects of System Geometry and Ambient Conditions on Solar Steam Generation for Evaporation Optimization
Authors: Zhang Yaoxin , Ravi Sai Kishore , Tan Swee Ching
Published: May 2019

Solar steam generation as an emerging solar desalination technology has drawn tremendous research attention owing to its enticing prospects in tackling the rising water crisis across the globe. Despite the numerous reports on materials with high evaporation rates, little is known about how the system geometry and ambient conditions impact the evaporation rate. The ambient relative humidity (RH), which can potentially impact on the evaporation process in the system is one such element that is not well studied. In this work, microchanneled balsa wood is employed as the research model in the quantitative investigations of these effects from the system itself and ambience. Direct implications and the interaction of various factors like ambient RH, hydrophilicity and specific weight of the material, carbonization thickness, and the water salinity are outlined. The trade‐off between surface water content and the interfacial temperature is revealed, and interestingly, a local “low‐humidity” zone is observed over the system's evaporation surface, which can sustain the evaporation even at extremely high RH. By tuning the system/ambience interactions, a systematic approach toward realizing the full potential of steam generators with optimized evaporation rate (10–20% enhancement) is therefore deemed achievable.
Light‐Emitting Transistors Based on Solution‐Processed Heterostructures of Self‐Organized Multiple‐Quantum‐Well Perovskite and Metal‐Oxide Semiconductors
Authors: Chaudhry Mujeeb Ullah , Wang Nana , Tetzner Kornelius , Seitkhan Akmaral , Miao Yanfeng , Sun Yan , Petty Michael C. , Anthopoulos Thomas D. , Wang Jianpu , Bradley Donal D. C.
Published: May 2019

Solution‐processed hybrid organic–inorganic perovskite semiconductors have demonstrated remarkable performance for both photovoltaic and light‐emitting‐diode applications in recent years, launching a new field of condensed matter physics. However, their use in other emerging optoelectronic applications, such as light‐emitting field‐effect transistors (LEFETs) has been surprisingly limited, wth only a few low‐performance devices reported. The development of hybrid LEFETs consisting of a solution‐processed self‐organized multiple‐quantum‐well lead iodide perovskite layer grown onto an electron‐transporting In2O3/ZnO heterojunction channel is reported. The multilayer transistors offer bifunctional characteristics, namely, transistor function with high electron mobility (>20 cm2 V−1 s−1) and a large current on/off ratio (>106), combined with near infrared light emission (λmax = 783 nm) and a promising external quantum efficiency (≈0.2% at 18 cd m−2). A further interesting feature of these hybrid LEFETs, in comparison to previously reported structures, is their highly uniform and stable emission characteristics, which make them attractive for smart‐pixel‐format display applications.
Semi‐analytical nanoscale‐extended surface tension correlation
Authors: Zhang Kaiqiang , Jia Na , Liu Lirong
Published: May 2019

Surface tensions (STs) are of critical importance to numerous natural phenomena and practical applications while most existing ST correlations are in the empirical formulations and limited to the bulk phase. In this study, a new semi‐analytical correlation based on the perturbation theory from the statistical thermodynamics is initially developed to calculate the STs of the various components in bulk and nanoconfined pores. The newly developed ST correlation is validated to be accurate and generalized in bulk and nanoconfined pores in comparison with the experimentally measured results at a wide range of temperatures. Furthermore, three important patterns with respect to the STs are determined: first, the STs are found to be reduced with the temperature increase but increase when the components become heavier in both bulk and nanoconfined pores; second, the STs of the mixtures tend to be more sensitive to the feed ratios at higher temperatures; last but not least, the nanoscale STs of the pure components are slightly lower than the bulk results at the same conditions.
Pollen and vegetative secondary chemistry of three pollen‐rewarding lupines
Authors: Heiling Jacob M. , Cook Daniel , Lee Stephen T. , Irwin Rebecca E.
Published: May 2019

Premise

Optimal defense theory predicts that selection should drive plants to disproportionally allocate resources for herbivore defense to tissues with high fitness values. Because pollen's primary role is the transport of gametes, plants may be expected to defend it from herbivory. However, for many animal‐pollinated plants, pollen serves a secondary role as a pollinator reward. These dual roles may present a conflict between selection to defend pollen from herbivores and selection to reward pollinators. Here, we investigate whether pollen secondary chemistry in three pollen‐rewardingLupinusspecies better reflects the need to defend pollen or reward pollinators.

Methods

Lupinus(Fabaceae) species are nectarless, pollen‐rewarding, and produce defensive quinolizidine and/or piperidine alkaloids throughout their tissues. We used gas chromatography to identify and quantitate the alkaloids in four aboveground tissues (pollen, flower, leaf, stem) of three western North American lupines,L. argenteus,L. bakeri, andL. sulphureus, and compared alkaloid concentrations and composition among tissues within individuals.

Results

InL. argenteusandL. sulphureus, pollen alkaloid concentrations were 11–35% of those found in other tissues. We detected no alkaloids inL. bakeripollen, though they were present in other tissues. Alkaloid concentrations were not strongly correlated among tissues within individuals. We detected fewer alkaloids in pollen compared to other tissues, and pollen contained no unique alkaloids.

Conclusions

Our results are consistent with the hypothesis that, in these pollen‐rewarding species, pollen secondary chemistry may reflect the need to attract and reward pollinators more than the need to defend pollen from herbivory.
Changes in work characteristics over 12 years: Findings from the 2002‐2014 US National NIOSH Quality of Work Life Surveys
Authors: Myers Stephanie , Govindarajulu Usha , Joseph Michael , Landsbergis Paul
Published: May 2019

Objectives

To assess changes in work characteristics, socioeconomic status inequalities in changes in work characteristics, and whether US workplaces are becoming more stressful.

Methods

We analyzed data from 5361 employed participants from the 2002, 2006, 2010, and 2014 NIOSH Quality of Work Life Surveys, based on representative samples of US workers. We used regression analyses to assess changes in job characteristics, adjusting for age, sex, race/ethnicity, education, work hours, and unemployment rate. For the regression analyses with continuous job characteristics, we created standardized variables allowing for the magnitude of changes to be directly compared between job characteristics.

Results

Over the period 2002‐2014, we observed statistically significant increases in job strain (+0.09 standard deviations (SD), P = 0.02), low job control (+0.10 SD, P = 0.03), and work‐family conflict (+0.15 SD, P = 0.001). No significant changes were observed for high job demand, low social support, and low reward. The largest increase in low job control was seen among service workers.

Conclusions

The increase in two cardiovascular disease risk factors, job strain, and low job control, might partially explain the slowing of the decline in US heart disease and stroke mortality rates.
Workplace injury rates and firm‐level turnover in Montana's oil and gas industry
Authors: Bradley Christopher , Brennan Julia , Wagner Barbara
Published: May 2019

Background

Do workers follow their self‐interest by minimizing injury risk in their employment decision? If so, employers could use injury reduction as a recruitment and retention strategy. This study explores whether injury incidence is associated with turnover in Montana's Oil and Gas industry.

Methods

A panel data set of Unemployment Insurance and Workers' Compensation administrative records from 2010 to 2015 was used to model the relationship between turnover and injury claim rates at the firm level.

Results

Total turnover and injury rates were found to be positively related while injury rates and separation rates had no such association. Quarters in which the employer experienced a severe injury had a 3.3 percentage point increase in separation rates.

Discussion

The findings suggest that injured workers contribute to increased turnover, but coworker turnover does not increase with increased injury rates in the firm. Secondary findings suggest a relationship between recent hires and increased injury rates, although further investigation is required.
Non‐Innocent Methylene Linker in Bridged Lewis Pair Initiators
Authors: Weger Michael , Grötsch Raphael K. , Knaus Maximilian G. , Giuman Marco M. , Mayer David C. , Altmann Philipp J. , Mossou Estelle , Dittrich Birger , Pöthig Alexander , Rieger Bernhard
Published: May 2019

Deprotonation usually occurs as an unwanted side reaction in the Lewis pair polymerization of Michael acceptors, for which the conjugated addition of the Lewis base to the acid‐activated monomer is the commonly accepted initiation mechanism. This has also been reported for B−P‐based bridged Lewis pairs (BLPs) that form macrocyclic addition products. We now show that the formerly unwanted deprotonation is the likely initiation pathway in the case of Al−P‐based BLPs. In a detailed study of a series of Al−P‐based BLPs, using a combination of single‐crystal diffraction experiments (X‐ray and neutron) and mechanistic investigations (experimental and computational), an active role of the methylene bridge was revealed, acting as a base towards the α‐acidic monomers. Additionally, the polymerization studies proved a living behavior combined with significantly high activities, narrow molecular mass distributions, and the possibility of copolymerization.
Tweaking the affinity of aryl‐substituted diazosalicylato‐ and pyridine ligands towards Zn (II) and its neighbors in the periodic system of the elements, Cu (II) and Cd (II), and their antimicrobial activity
Authors: Basu Baul Tushar S. , Nongsiej Khrawborlang , Lamin Ka‐Ot Augustine , Joshi Santa Ram , Rojas León Irán , Höpfl Herbert
Published: May 2019

A series of six new Zn (II) compounds, viz., [Zn(HLASA)2(Py)2] (1), [Zn(HLMASA)2(Py)2] (2), [Zn(HLMASA)2(4‐MePy)2] (3), [Zn(HLCASA)2(4‐MePy)2] (4), [Zn(HLBASA)2(Py)2] (5), [Zn(HLBASA)2(4‐MePy)2] (6) and representative Cu (II) and Cd (II) complexes, viz., [Cu(HLASA)2(Py)2(H2O)] (7) and [Cd(HLBASA)2(Py)3] (8) [(HLXASA)− = para‐substituted 5‐[(E)‐2‐(aryl)‐1‐diazenyl]‐2‐hydroxybenzoate with X = H (ASA), Me (MASA), Cl (CASA) or Br (BASA); Py = pyridine; 4‐MePy = 4‐methylpyridine] have been synthesized and characterized by spectroscopic techniques and single‐crystal X‐ray diffraction analysis. The structural characterization of the compounds revealed distorted tetrahedral (1–6), square‐pyramidal (7) and pentagonal‐bipyramidal (8) coordination geometries around the metal atom, in which the aryl‐substituted diazosalicylate ligands are coordinated only through the oxygen atoms of carboxylate groups, either in an anisobidentate or isobidentate mode; meanwhile, the 2‐hydroxy groups of the monoanionic ligand (HLXASA)− are involved only in intramolecular O‐H···O hydrogen bonds with the carboxylate function. In the crystal structures of 1–8, the complex molecules are assembled by π‐stacking interactions giving mostly infinite 1D strands. The intermolecular binding in the solid state structures is accomplished by diverse additional non‐covalent contacts including C‐H···O, C‐H···N, C‐H···π, C‐H···Br, O···Br, Br···π and van der Waals contacts. Although the primary and secondary ligands in the Zn (II) complex series 1–6 carry different substituents at the periphery (X = H, Me, Cl, Br for (HLXASA)− and R = H, Me for 4‐Py‐R), five of the crystal structures were isostructural. Additionally, the antimicrobial activity of the pro‐ligands H2LXASA and their Zn (II), Cu (II) and Cd (II) compounds were studied in a comparative manner, showing high sensitivity (IZD ≥ 20) against Bacillus subtilis.
Biocomposites of poly(lactic acid) and lactic acid oligomer‐grafted bacterial cellulose: It's preparation and characterization
Authors: Patwa Rahul , Saha Nabanita , Sáha Petr , Katiyar Vimal
Published: May 2019

This work demonstrates the synthesis of lactic acid oligomer‐grafted‐untreated bacterial cellulose (OLLA‐g‐BC) by in situ condensation polymerization which increased compatibilization between hydrophobic poly(lactic acid) (PLA) and hydrophilic BC, thus enhancing various properties of PLA‐based bionanocomposites, indispensable for stringent food‐packaging applications. During the synthesis of OLLA‐g‐BC, hydrophilic BC is converted into hydrophobic due to structural grafting of OLLA chains with BC molecules. Subsequently, bionanocomposites films are fabricated using solution casting technique and characterized for structural, thermal, mechanical, optical, and gas‐barrier properties. Morphological images showed uniform dispersion of BC nanospheres in the PLA matrix, which shows strong filler–matrix interaction. The degradation temperatures for bionanocomposites films were above PLA processing temperature indicating that bionanocomposite processing can be industrially viable. Bionanocomposites films displayed decrease in glass transition (Tg) and ~20% improvement in elongation with 10 wt % fillers indicating towards plasticization of PLA. PLA/OLLA‐g‐BC films showed a slight reduction in optical transparency but had excellent UV‐blocking characteristics. Moreover, dispersed BC act as blocking agents within PLA matrix, reducing the diffusion through the bionanocomposite films which showed ~40% improvement in water‐vapor barrier by 5 wt % filler addition, which is significant. The reduced Tg, improved elongation combined with improved hydrophobicity and water‐vapor barrier make them suitable candidate for flexible food‐packaging applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47903.
Flexible strain sensors based on epoxy/graphene composite film with long molecular weight curing agents
Authors: Meng Qingshi , Zhao Yu , Liu Zhiwen , Han Sensen , Lu Shaowei , Liu Tianqing
Published: May 2019

Flexible strain sensors based on epoxy/graphene composite film with long molecular weight curing agents have critical roles in the development of advanced polymer composite films that combine mechanical robustness with functional properties such as electrical conductivity for many applications. In this experiment, flexible epoxy/GnP composite film is obtained by using flexible curing agent J2000. A percolation threshold of electrical conductivity was observed at merely 0.97 vol% GnPs, and the composite electrical conductivity increased to 10−6 S/cm at 5.0 vol %. The composite films were mechanically strong enough to be used as a flexible strain sensor. Our sensor can clearly detect the stretching of the forearm skin caused by a fist pulse and back of hand movement and achieve an enhancement of the resistance signal of up to 50%. When the GnPs content reaches 5%, Young's modulus and tensile strength increase to 21 MPa and 1.3 MPa, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47906.
Regional inequality in urban China, allowing for spatial cost of living differences: Evidence from a hedonic analysis of apartment prices
Authors: Li Chao , Gibson John , Boe‐Gibson Geua
Published: May 2019

Studies of inequality in China typically ignore cost of living differences between areas. Under the Balassa–Samuelson effect, nontradeables cost more in richer areas, so nominal inequality exceeds real inequality. This especially matters in China, where spatial cost of living differences should grow with recent development of urban housing markets. We use new data on apartment prices in 104 cities in China to develop housing‐related spatial deflators. The level of spatial inequality in urban China is overstated by 27% if cost of living differences are ignored. Our hedonic analysis of 41,000 individual apartment sales shows that most price variation is between areas, rather than from features of individual apartments. The dominant trend in the reform era is for regional inequality in China to decline, contrary to the common perceptions. In nominal terms, the Theil index for interprovincial inequality in 2016 is just 46% of its 1978 level. The current results imply that the fall in inequality in real terms would be even greater.
Benthic habitat modelling and mapping as a conservation tool for marine protected areas: A seamount in the western Mediterranean
Authors: de la Torriente Ana , González‐Irusta Jose Manuel , Aguilar Ricardo , Fernández‐Salas Luis Miguel , Punzón Antonio , Serrano Alberto
Published: May 2019

An ecologically representative, well‐connected, and effectively managed system of marine protected areas (MPAs) has positive ecological and environmental effects as well as social and economic benefits. Although progress in expanding the coverage of MPAs has been made, the application of management tools has not yet been implemented in most of these areas.

In this work, distribution models were applied to nine benthic habitats on a Mediterranean seamount within an MPA for conservation purposes. Benthic habitat occurrences were identified from 55 remotely operated vehicle (ROV) transects, at depths from 76 to 700 m, and data derived from multibeam bathymetry. Generalized additive models (GAMs) were applied to link the presence of each benthic habitat to local environmental proxies (depth, slope, backscatter, aspect, and bathymetric position index, BPI).

The main environmental drivers of habitat distribution were depth, slope, and BPI. Based on this result, five different geomorphological areas were distinguished. A full coverage map indicating the potential benthic habitat distribution on the seamount was obtained to inform spatial management.

The distribution of those habitats identified as vulnerable marine ecosystems (VMEs) was used to make recommendations on zonation for developing the management plan of the MPA. This process reveals itself as an appropriate methodological approach that can be developed in other areas of the Natura 2000 marine network.
Base‐Promoted α‐Alkylation of Arylacetonitriles with Alcohols
Authors: Roy Bivas Chandra , Ansari Istikhar A. , Samim Sk. Abdus , Kundu Sabuj
Published: May 2019

A practical method to synthesize α‐alkylated arylacetonitriles from arylacetonitriles and alcohols without using any expensive transition metal complexes is demonstrated here. Following this base‐catalysed sustainable procedure, various arylacetonitriles were successfully alkylated with different alcohols. The practical applicability of this protocol was extended by one‐pot synthesis of important carboxylic acid derivatives.
Dams: The Missed Risk in Plain Sight
Authors: Glenn Sandra L. , Smith Sandy A.
Published: May 2019

Dams are often overlooked as potential threats to infrastructure, but one Georgia county is creating greater awareness and preparedness.
Take a Mixed Approach to Mixing
Authors: Malinaro Ann , Rhoades Jacqueline , Pennock William , Gutierrez Felipe
Published: May 2019

Authors’ note: This column, prepared by members of the AWWA Coagulation and Filtration Committee, is the first in the series “Hot Topics in Water Quality,” presented by the Water Quality Technology Division, as introduced in the April 2019 issue of Journal AWWA. Next month's column will feature hot topics from the AWWA Source Water Protection Committee.