bluuebunny/crossref_metadata_2025 huggingface dataset:
Relação entre ansiedade e modulação autonômica cardíaca
Authors: Pinheiro Giovanni Vieira , Martiniano Eli Carlos , Alcântara Guilherme Correia , Silva José Ramon Alcântara da , Silva Maria do Socorro Da , Monteiro Larissa Raylane Lucas , Mangueira Luana Bezerra , Moraes Yasmim Mota de , Valenti Vitor Engrácia , Santana Milana Drumond Ramos
Published: December 2018

A ansiedade é caracterizada pelo sentimento de tensão, nervosismo, apreensão e preocupação que pode alterar a modulação do sistema nervoso autônomo sobre a condução elétrica ligada ao coração, determinando a intensidade nos batimentos cardíacos modificando a variabilidade da frequência cardíaca que é um importante indicador de condições normais e patológicas. Assim, o objetivo do estudo foi analisar a relação existente entre a ansiedade e o processo de regulação autonômica cardíaca. Este estudo trata-se de uma revisão integrativa desenvolvido por meio de buscas nas bases de dados da Lilacs, Medline e SciELO, com os descritores em ciências da saúde e operador booleano: ansiedade AND frequência cardíaca e, ansiedade AND sistema nervoso autônomo. A busca foi realizada durante o mês de setembro de 2017, sendo incluídos artigos disponíveis na íntegra; em português e inglês e; publicados nos últimos 06 anos. Excluiu-se artigos que não fossem originais, teses, dissertações e monografias. Obteve-se um total de 10 artigos, nos quais observou-se que a ansiedade altera a resposta autonômica, assim quando o corpo entra em tensão, aumentase a frequência cardíaca, o predomínio do sistema simpático e no relaxamento ocorre o domínio parassimpático. Assim indivíduos portadores de ansiedade apresentam menor variação na frequência cardíaca e possuem uma capacidade menor de interação social. Com isto, evidencia-se uma baixa adaptação do sistema nervoso autônomo em casos de ansiedade, sendo que a variabilidade da frequência cardíaca encontra-se reduzida; condição esta que pode ser classificada como patológica.
Estresse oxidativo na interrupção da ventilação mecânica em pacientes vítimas de traumatismo cranioencefálico: um estudo randomizado e cego
Authors: Moraes Anderson Antunes da Costa , Araujo Luã Alves , Araújo Rodrigo Alcântara Carnevalli de , Rocha Rodrigo Santiago Barbosa , Costa Leonardo Ramos Nicolau da , Gonçalves Kéven Lorena de Paula , Lima Gabriela Martins de
Published: December 2018

Introdução: Os efeitos tóxicos do oxigênio não estão bem estabelecidos em seres humanos. Objetivo: Analisar os níveis de estresse oxidativo (EOx) na interrupção da ventilação mecânica (VM) em pacientes vítimas de TCE. Métodos: Estudo prospectivo, longitudinal, analítico, randomizado e cego. Participaram 12 pacientes: PSV (n=6) e grupo Tubo-T (n=6). A interrupção da VM deu-se em: PSV- (Δ 7 cmH2O) e PEEP (5 cmH2O) durante 30 minutos; Tubo-T - o paciente foi conectado ao tubo T com FiO2 a 0,4 durante 30 minutos. Realizou-se avaliação morfológica do EOx no plasma sanguíneo pelo Dry layer oxidative test. A coleta foi realizada: com 24h de VM, antes do teste, em 15’ de teste e após o teste PSV ou Tubo-T. Para análise da normalidade utilizou-se o teste de Shapiro-Wilk para análise intragrupo e intergrupos, o teste ANOVA seguido de Tukey; para correlação-Correlação de Spearman (p valor 5%). Resultados: Não houve aumento estatisticamente significativo na descontinuidade da matriz extracelular nos grupos (p>0,05). Os níveis de EOx encontraram-se elevados (grau III–moderado) nas primeiras avaliações. Não foi encontrada correlação significativa entre os parâmetros de VM com o EOx. O grupo PSV permaneceu em média 12.33 dias sob VM, tendo EOx de 29.02 (grau III/ moderado) – r=0.8, p=0.01; o grupo Tubo T em média 12.83±2.2 dias, tendo EOx de 31.03±5.41 (grau IV/grave)- r=0.9, p=0.07. Conclusão: Não houve diferença no comportamento do EOx entre os métodos de interrupção da VM. No entanto, o EOx aumentou com o tempo de VM.
Book review of: Transformational Entrepreneurship by Vanessa Ratten and Paul Jones
Authors: Kauppinen Antti
Published: December 2018

Book review of: Transformational Entrepreneurship by Vanessa Ratten and Paul Jones. Routlege Frontiers of Business Management, Routlege, London and New York, 2019. 210pp. ISBN-13: 978-1-138-48475-7
The oldest ceratosaurian (Dinosauria: Theropoda), from the Lower Jurassic of Italy, sheds light on the evolution of the three-fingered hand of birds
Authors: Dal Sasso Cristiano , Maganuco Simone , Cau Andrea
Published: December 2018

The homology of the tridactyl hand of birds is a still debated subject, with both paleontological and developmental evidence used in support of alternative identity patterns in the avian fingers. With its simplified phalangeal morphology, the Late Jurassic ceratosaurianLimusaurushas been argued to support a II–III–IV digital identity in birds and a complex pattern of homeotic transformations in three-fingered (tetanuran) theropods. We report a new large-bodied theropod,Saltriovenator zanellaigen. et sp. nov., based on a partial skeleton from the marine Saltrio Formation (Sinemurian, lowermost Jurassic) of Lombardy (Northern Italy). Taphonomical analyses show bone bioerosion by marine invertebrates (first record for dinosaurian remains) and suggest a complex history for the carcass before being deposited on a well-oxygenated and well-illuminated sea bottom.Saltriovenatorshows a mosaic of features seen in four-fingered theropods and in basal tetanurans. Phylogenetic analysis supports sister taxon relationships between the new Italian theropod and the younger Early JurassicBerberosaurusfrom Morocco, in a lineage which is the basalmost of Ceratosauria. Compared to the atrophied hand of later members of Ceratosauria,Saltriovenatordemonstrates that a fully functional hand, well-adapted for struggling and grasping, was primitively present in ceratosaurians. Ancestral state reconstruction along the avian stem supports 2-3-4-1-X and 2-3-4-0-X as the manual phalangeal formulae at the roots of Ceratosauria and Tetanurae, confirming the I–II–III pattern in the homology of the avian fingers. Accordingly, the peculiar hand ofLimusaurusrepresents a derived condition restricted to late-diverging ceratosaurians and cannot help in elucidating the origin of the three-fingered condition of tetanurans. The evolution of the tridactyl hand of birds is explained by step-wise lateral simplification among non-tetanuran theropod dinosaurs, followed by a single primary axis shift from digit position 4 to 3 at the root of Tetanurae once the fourth finger was completely lost, which allowed independent losses of the vestigial fourth metacarpal among allosaurians, tyrannosauroids, and maniraptoromorphs. With an estimated body length of 7.5 m,Saltriovenatoris the largest and most robust theropod from the Early Jurassic, pre-dating the occurrence in theropods of a body mass approaching 1,000 Kg by over 25 My. The radiation of larger and relatively stockier averostran theropods earlier than previously known may represent one of the factors that ignited the trend toward gigantism in Early Jurassic sauropods.
Undocumented translocations spawn taxonomic inflation in Sri Lankan fire rasboras (Actinopterygii, Cyprinidae)
Authors: Sudasinghe Hiranya , Herath Jayampathi , Pethiyagoda Rohan , Meegaskumbura Madhava
Published: December 2018

A recent (2013) taxonomic review of the freshwater-fish genusRasboroides, which is endemic to Sri Lanka, showed it to comprise four species:R. vaterifloris,R. nigromarginatus,R. pallidusandR. rohani.Here, using an integrative-taxonomic analysis of morphometry, meristics and mitochondrial DNA sequences ofcytochrome b(cytb) andcytochrome oxidase subunit 1(coi), we show thatR. nigromarginatusis a synonym ofR. vaterifloris, and thatR. rohaniis a synonym ofR. pallidus.The creation and recognition of unnecessary taxa (‘taxonomic inflation’) was in this case a result of selective sampling confounded by a disregard of allometry. The population referred toR. rohaniin the Walawe river basin represents an undocumented trans-basin translocation ofR. pallidus, and a translocation into the Mahaweli river ofR. vaterifloris, documented to have occurredca1980, in fact involvesR. pallidus.A shared haplotype suggests the latter introduction was likely made from the Bentara river basin and not from the Kelani, as claimed. To stabilize the taxonomy of these fishes, the two valid species,R. vateriflorisandR. pallidus, are diagnosed and redescribed, and their distributions delineated. We draw attention to the wasteful diversion of conservation resources to populations resulting from undocumented translocations and to taxa resulting from taxonomic inflation. We argue against translocations except where mandated by a conservation emergency, and even then, only when supported by accurate documentation.
The feasibility of predicting ground reaction forces during running from a trunk accelerometry driven mass-spring-damper model
Authors: Nedergaard Niels J. , Verheul Jasper , Drust Barry , Etchells Terence , Lisboa Paulo , Robinson Mark A. , Vanrenterghem Jos
Published: December 2018

Background

Monitoring the external ground reaction forces (GRF) acting on the human body during running could help to understand how external loads influence tissue adaptation over time. Although mass-spring-damper (MSD) models have the potential to simulate the complex multi-segmental mechanics of the human body and predict GRF, these models currently require input from measured GRF limiting their application in field settings. Based on the hypothesis that the acceleration of the MSD-model’s upper mass primarily represents the acceleration of the trunk segment, this paper explored the feasibility of using measured trunk accelerometry to estimate the MSD-model parameters required to predict resultant GRF during running.

Methods

Twenty male athletes ran at approach speeds between 2–5 m s−1. Resultant trunk accelerometry was used as a surrogate of the MSD-model upper mass acceleration to estimate the MSD-model parameters (ACCparam) required to predict resultant GRF. A purpose-built gradient descent optimisation routine was used where the MSD-model’s upper mass acceleration was fitted to the measured trunk accelerometer signal. Root mean squared errors (RMSE) were calculated to evaluate the accuracy of the trunk accelerometry fitting and GRF predictions. In addition, MSD-model parameters were estimated from fitting measured resultant GRF (GRFparam), to explore the difference between ACCparam and GRFparam.

Results

Despite a good match between the measured trunk accelerometry and the MSD-model’s upper mass acceleration (median RMSE between 0.16 and 0.22 g), poor GRF predictions (median RMSE between 6.68 and 12.77 N kg−1) were observed. In contrast, the MSD-model was able to replicate the measured GRF with high accuracy (median RMSE between 0.45 and 0.59 N kg−1) across running speeds from GRFparam. The ACCparam from measured trunk accelerometry under- or overestimated the GRFparam obtained from measured GRF, and generally demonstrated larger within parameter variations.

Discussion

Despite the potential of obtaining a close fit between the MSD-model’s upper mass acceleration and the measured trunk accelerometry, the ACCparam estimated from this process were inadequate to predict resultant GRF waveforms during slow to moderate speed running. We therefore conclude that trunk-mounted accelerometry alone is inappropriate as input for the MSD-model to predict meaningful GRF waveforms. Further investigations are needed to continue to explore the feasibility of using body-worn micro sensor technology to drive simple human body models that would allow practitioners and researchers to estimate and monitor GRF waveforms in field settings.
Absorption
Authors: Karayiannis Nikos CH , Laso Manuel
Published: December 2018

Absorption, or gas absorption, is a unit operation used in the chemical industry to separate gases by washing or scrubbing a gas mixture with a suitable liquid. One or more of the gas components dissolves or is absorbed in the liquid and is thus removed from the mixture. Absorption is currently one of the most important processes in chemical engineering not only for product recovery but also, and perhaps mainly, for pollutant removal. Intense industrial and academic effort is focused on optimizing the process, in terms process efficiency as well as commercial aspects.

In this article, the fundamental principles of gas solubility and mass transfer, design and operation of industrial equipment with relevant examples of typical commercial gas absorption processes are discussed, including recent developments in these areas.
Environmental Remediation with Electrochemical Technologies
Authors: Chen Long , Rajic Ljiljana , Zhao Yuwei , Hetrick Kimberly , Hojabri Shirin , Alshawabkeh Akram , Xue Yunfei , Zhou Wei
Published: December 2018

Significant concerns continue to be raised over environmental pollution of soils and water resources. Chemical fate and transport coupled with redox manipulation are the primary processes that have been considered for removing contamination and minimizing exposure. Electrochemical processes utilize electron transfer to drive transport of chemicals and redox manipulation for treatment of contaminated media. Electrokinetic remediation relies on the electric field to transport contaminants in low permeability soils toward the electrode vicinity for removal. In water cleanup, both electroreduction and electrooxidation have been used. Electroreduction has been used for dechlorination and defluorination of halogenated calcitrant compounds. Electrooxidation has also gained significant potential for transformation of many legacy and emerging contaminants. For example, organic contaminants could be oxidized directly on anode surface (direct anodic oxidation), by electrochemically generated hydroxyl radicals or by other electrochemically generated oxidants (indirect anodic oxidation). In this article, we present an overview of the state‐of‐the‐art electrochemical processes for treatment of contaminated soil and water. We also describe a perspective for future research directions in the field of electrochemical treatment of contaminated media.
Sex, Gender, and Crime
Authors: McCarthy Bill , Carter Angela
Published: December 2018

For several decades, the study of gender and crime has generally eclipsed a focus on sex and crime. This change reflects new understandings of all three concepts – sex, gender, and crime. It also reflects a shift from a focus on males and the crimes they commit to one that includes females and their involvement in illegal behavior. This entry summarizes how sociologists of crime define sex, gender, and crime and discusses two broad categories of theories they use to explain how these concepts are connected. One body of theory suggests that male and female offending have the same origins and that gender differences in offending reflect gender differences in exposure to crime's causes. A second body argues that male and female offending may share some origins, but that each has unique causes.
Sexual Health
Authors: Lottes Ilsa
Published: December 2018

The concept of sexual health first appeared in publications in the 1960s, but in the late 1980s the use of the term increased dramatically in a wide range of disciplines. The meaning and application of sexual health to public health varies depending on sociocultural, political, and historical contexts. At the 1994 International Conference on Population and Development and the 1995 Fourth World Conference on Women, feminists, women's health advocates, and proponents of human rights presented a new approach to sexual health. This approach emphasized the need for women's empowerment, issues related to gender relations and inequality, justice for diverse sexualities, and the importance of adopting human rights/sexual rights frameworks in public policies and family planning programs. Other meanings and applications of sexual health are also described in this entry.
Social Psychology, Applied
Authors: Mankowski Eric , O'Connor Emma
Published: December 2018

Applied social psychology develops and uses theories and research about how people influence others' thoughts, feelings, and behavior to address social and health problems caused by human behavior, such as racial, class, and gender discrimination, environmental pollution and natural resource depletion, interpersonal violence, and drug misuse. The field emphasizes an interdependent and cyclical relationship among theory development, research in social settings, and application of knowledge through action and intervention. A wide variety of experimental, quasi‐experimental, correlational, and longitudinal research designs and methods of data collection including surveys, observation, and qualitative interviews are employed. Knowledge from the field has contributed to successful interventions that decrease prejudice and discrimination, increase conservation of natural resources and recycling, improve jury decision‐making, and increase cooperation and reduce conflict between social groups. With the increasing complexity of social problems and systems, applied social psychology is needed more than ever to improve human well‐being.
Stratification Systems: Openness
Authors: Bögenhold Dieter
Published: December 2018

The concept of stratification refers to the idea of vertical segmentation in a sense of having more or less resources. Degrees of stratification are always relational and they express degrees of social inequality. Open stratification systems exist when a society leaves channels for upward or downward mobility, where actors or families can change their position inter or intragenerationally. The classic idea in Marx's categorization was that access to means of production serves as the pivot point of all sociological and economic analysis. An early contrast to the dominant Marxist view was elaborated by Max Weber, who stressed the fact of differentiation. Bourdieu sees the social world in terms of a metaphor: Consider a multidimensional social sphere in which different groups of actors reflect, on the one hand, the sphere of social position and, on the other hand, the sphere of lifestyles. Other authors emphasize the growing relativity of the class concept due to increasing trends of mobility caused by education, urbanization, and changing demographic patterns, including the declining significance of the institution of the family, which leads more and more to a multicolored puzzle of conditions, lifestyles, attitudes, and behavior.
Spokespersonship
Authors: Pels Dick
Published: December 2018

In modern communication‐ and media‐driven cultures, spokespersonship has increasingly become professionalized, offering an indispensable vehicle for advocating the identity and interests of persons, groups, and institutions. But, on a deeper level, we all act as spokespersons, by “presenting” that which is not immediately at hand (persons, things, ideas) in current face‐to‐face situations. All such representational acts crucially depend on belief and credit, and hence on the authority and credibility of the spokesperson. Representation therefore comes with a permanent risk of usurpation: spokespersons may take the place and appropriate the power of “their” subjects and objects. A critical theory of spokespersonship must be on permanent alert for such “identitarian” forms of representation and the symbolic power yielded by them.
Top Management Team
Authors: Díaz‐Fernández M. Carmen , González‐Rodríguez M. Rosario , Simonetti Biagio
Published: December 2018

Top management team (TMT) is a relevant managerial topic widely recognized in company environments and in the academic literature. In this framework, most practitioners and theorists pursue in‐depth knowledge of the notion of TMT and its internal functioning since it is a key driver to determine the company's strategic behavior and hence outcomes. Despite the relevance of TMT, no agreement can be found in the literature regarding the relationship beteween TMT, strategic pattern, and company performance. This is mainly attributed to methodological weakness in most of the empircal studies. New theories are emerging to solve that weakness to make the topic and the upper echelons theory, the main theory of TMT, continue in significance.
Women in Science
Authors: Rosser Sue V.
Published: December 2018

The work of historians of science, data analysts, gender studies scholars, as well as sociologists of science informs the interdisciplinary field of women in science. Historians have elucidated the changing impact of gender and gender roles on women's lives as scientists at different historical times, different geographic locations, and in different scientific disciplines. Data gathered by national governments on the numbers and status of women in science provide a mechanism to document the numbers of women in different disciplines and the positions they hold. Relatively recently, the US National Science Foundation has recognized the role of intersectionality and its impact upon the percentages of degrees obtained by women in different STEM disciplines, the sector or institutional type of employment, unemployment rates and salaries, as well as women's daily experiences as scientists.
Cardiovascular Morbidity and Mortality in Primary Sjögren's Syndrome: A Systematic Review and Meta‐Analysis
Authors: Beltai Aurélie , Barnetche Thomas , Daien Claire , Lukas Cedric , Gaujoux‐Viala Cécile , Combe Bernard , Morel Jacques
Published: December 2018

Objective

Patients with immune‐mediated inflammatory diseases such as rheumatoid arthritis or systemic lupus erythematosus are at increased risk of cardiovascular disease. However, the cardiovascular risk of patients with primary Sjögren's syndrome (SS) remains poorly studied. We aimed to investigate the association between primary SS and cardiovascular morbidity and mortality.

Methods

We performed a systematic review of articles in Medline and the Cochrane Library and recent abstracts from US and European meetings, searching for reports of randomized controlled studies of cardiovascular morbidity and cardiovascular mortality in primary SS. The relative risk (RR) values for cardiovascular morbidity and mortality associated with primary SS were collected and pooled in a meta‐analysis with a random‐effects model by using Review Manager (Cochrane collaboration).

Results

The literature search revealed 484 articles and abstracts of interest; 14 studies (67,124 patients with primary SS) were included in the meta‐analysis. With primary SS versus control populations, the risk was significantly increased for coronary morbidity (RR 1.34 [95% confidence interval (95% CI) 1.06–1.38]; P = 0.01), cerebrovascular morbidity (RR 1.46 [95% CI 1.43–1.49]; P < 0.00001), heart failure rate (odds ratio 2.54 [95% CI 1.30–4.97]; P < 0.007), and thromboembolic morbidity (RR 1.78 [95% CI 1.41–2.25]; P < 0.00001), with no statistically significant increased risk of cardiovascular mortality (RR 1.48 [95% CI 0.77–2.85]; P = 0.24).

Conclusion

This meta‐analysis demonstrates that primary SS is associated with increased cardiovascular morbidity, which suggests that these patients should be screened for cardiovascular comorbidities and considered for preventive interventions, in a multidisciplinary approach with cardiologists.
High Thermoelectric Performance in the Wide Band‐Gap AgGa1‐xTe2 Compounds: Directional Negative Thermal Expansion and Intrinsically Low Thermal Conductivity
Authors: Su Xianli , Zhao Na , Hao Shiqiang , Stoumpos Constantinos C. , Liu Mengyuan , Chen Haijie , Xie Hongyao , Zhang Qingjie , Wolverton Chris , Tang Xinfeng , Kanatzidis Mercouri G.
Published: December 2018

A deficiency of Ga in wide band‐gap AgGa1‐xTe2 semiconductors (1.2 eV) can be used to optimize the electrical transport properties and reduce the thermal conductivity to achieve ZT > 1 at 873 K. First‐principles density functional theory calculations and a Boson peak observed in the low temperature heat capacity data indicate the presence of strong coupling between optical phonons with low frequency and heat carrying acoustical phonons, resulting in a depressed maximum of Debye frequency in the first Brillouin zone and low phonon velocities. Moreover, the AgTe bond lengths and TeAgTe bond angles increase with rising temperature, leading to a significant distortion of the [AgTe4]7− tetrahedra, but an almost unmodified [GaTe4]5− tetrahedra. This behavior results in lattice expansion in the ab‐plane and contraction along the c‐axis, corresponding to the positive and negative Gruneisen parameters in the phonon spectral calculations. This effect gives rise to the large anharmonic behavior of the lattice. These factors together with the low frequency vibrations of Ag and Te atoms in the structure lead to an ultralow thermal conductivity of 0.18 W m−1 K−1 at 873 K.
Detection of Glioma‐Derived Exosomes with the Biotinylated Antibody‐Functionalized Titanium Nitride Plasmonic Biosensor
Authors: Qiu Guangyu , Thakur Abhimanyu , Xu Chen , Ng Siu‐Pang , Lee Youngjin , Wu Chi‐Man Lawrence
Published: December 2018

Titanium nitride (TiN), as an excellent alternative plasmonic supporting material compared to gold and silver, exhibits tunable plasmonic properties in the visible and near‐infrared spectra. However, label‐free surface plasmon resonance biosensing with TiN is seldom reported due to lack of proper surface functionalization protocols. Herein, this study reports biotinylated antibody‐functionalized TiN (BAF‐TiN) for high‐performance label‐free biosensing applications. The BAF‐TiN biosensor can quantitatively detect exosomes of 30–200 nm extracellular vesicles, isolated from a human glioma cell line. The limit of detection for an exosomal membrane protein with the BAF‐TiN biosensor is found to be 4.29 × 10−3µg mL−1 for CD63, an exosome marker, and 2.75 × 10−3µg mL−1 for epidermal growth factor receptor variant‐III, a glioma specific mutant protein, respectively. In conclusion, combining the biocompatibility, high stability, and excellent label‐free sensing performance of TiN, the BAF‐TiN biosensor could have great potential for the detection of cancer biomarkers, including exosomal surface proteins.
Robust High Thermoelectric Harvesting Under a Self‐Humidifying Bilayer of Metal Organic Framework and Hydrogel Layer
Authors: Kim Byeonggwan , Na Jongbeom , Lim Hanwhuy , Kim Younghoon , Kim Jinbo , Kim Eunkyoung
Published: December 2018

Robust thermoelectric harvesting is explored from a proton‐doped mixed ionic conductive (PMIC) film under water‐harvesting metal organic framework (MOF) film coupled with hydrogel layer (MOF/HG). As a PMIC, highly doped poly(3,4‐ethylenedioxythiophene)s with poly(styrene sulfonate) (PEDOT:PSS) is prepared by precisely controlling the proton doping to afford a stable and high thermoelectric PMIC. Among the PMICs, the PEDOT:PSS film doped with 30 wt% of poly(styrene sulfonic acid) (PSSH) recorded a Seebeck coefficient of over 16.2 mV K−1 and a thermal voltage of 81 mV for a temperature gradient (ΔT) of 5 K. The thermal charging on PMICs afforded high thermal voltage and current output, reproducibly, to show cumulative thermoelectric nature. Environmentally sustainable thermoelectric harvesting is achieved from a PMIC under a MOF/HG, prepared by water‐harvesting MOF‐801 coupled with a HG layer, to provide constant relative humidity of 90% and Voc over 72 h at ambient condition.
Transport and Charge Carrier Chemistry in Lithium Sulfide
Authors: Lorger Simon , Usiskin Robert E. , Maier Joachim
Published: December 2018

Lithium sulfide is a functional material of great importance for battery research, since it is the discharge product in Li–S cathodes and a frequent component of anode passivation layers. In both cases, transport of charge carriers in Li2S is critical for performance. The exploration of charge carrier chemistry in such a simple binary compound is also of fundamental scientific interest. For that purpose, impedance spectroscopy and electromotive force measurements are performed over a broad range of temperatures and doping conditions. The results indicate predominant ion conduction and can be quantitatively explained by a defect chemical model based on Frenkel disorder and vacancy‐dopant association. Mobilities and migration barriers for both vacancy and interstitial defects are deduced. The thermodynamic and kinetic parameters derived for Li+ transport in antifluorite Li2S show remarkable agreement with the analogous parameters for F− transport in fluorite compounds such as BaF2, thereby improving the structural understanding of charge carrier chemistry in such compounds. An application of these results to passivation layers in solid state batteries is also discussed.
Lipid Nanovesicles by Microfluidics: Manipulation, Synthesis, and Drug Delivery
Authors: Liu Chao , Feng Qiang , Sun Jiashu
Published: December 2018

Lipid nanovesicles, including endogenous exosomes and synthetic lipid nanoparticles, have shown great potential in disease diagnostics, drug delivery, and cancer biology. Naturally secreted nanovesicles are promising biomarkers for early detection of cancers in vitro. Synthetic nanovesicles serve as robust drug delivery systems with enhanced tumor targeting in vivo. Microfluidic platforms with features of excellent flow control and rapid mixing are exploited as versatile tools for studying lipid nanovesicles of small sizes and delicate structures. Here, an overview of microfluidics for precise manipulation and synthesis of lipid nanovesicles is provided. The mechanisms of isolation and detection of exosomes in microfluidics, as well as the clinical utility of exosomes for cancer diagnosis, are discussed. Several microfluidic designs for controlled assembly of a variety of lipid nanovesicles are highlighted. Opportunities and outstanding challenges of microfluidics‐based investigation of lipid nanovesicles are discussed.
Membrane Separation in Organic Liquid: Technologies, Achievements, and Opportunities
Authors: Liang Bin , He Xiao , Hou Junjun , Li Lianshan , Tang Zhiyong
Published: December 2018

Membrane technology is one of the most promising technologies for separation and purification that is routinely and commercially employed in aqueous solutions. In comparison, its applications in organic solvents are severely underdeveloped mainly due to the poor stability of traditional polymer membranes in organic solvents. The emerging materials such as crosslinked polymers, covalent organic frameworks, metal–organic frameworks, conjugated microporous polymers, carbon molecular sieves, and graphene provide the solutions to address this problem. The membranes constructed with these novel materials show outstanding separation performance in regard to both high selectivity and solvent permeability, greatly pushing forward utilization of membrane technology in organic media. Here, an overview of the most important organic mixtures that need to be separated, the major separation processes adopted nowadays in organic solvents, and the recent progress in new developed membranes is provided.
Dynamic Control of Light Direction Enabled by Stimuli‐Responsive Liquid Crystal Gratings
Authors: Zola Rafael S. , Bisoyi Hari Krishna , Wang Hao , Urbas Augustine M. , Bunning Timothy J. , Li Quan
Published: December 2018

The ability to control light direction with tailored precision via facile means is long‐desired in science and industry. With the advances in optics, a periodic structure called diffraction grating gains prominence and renders a more flexible control over light propagation when compared to prisms. Today, diffraction gratings are common components in wavelength division multiplexing devices, monochromators, lasers, spectrometers, media storage, beam steering, and many other applications. Next‐generation optical devices, however, demand nonmechanical, full and remote control, besides generating higher than 1D diffraction patterns with as few optical elements as possible. Liquid crystals (LCs) are great candidates for light control since they can form various patterns under different stimuli, including periodic structures capable of behaving as diffraction gratings. The characteristics of such gratings depend on several physical properties of the LCs such as film thickness, periodicity, and molecular orientation, all resulting from the internal constraints of the sample, and all of these are easily controllable. In this review, the authors summarize the research and development on stimuli‐controllable diffraction gratings and beam steering using LCs as the active optical materials. Dynamic gratings fabricated by applying external field forces or surface treatments and made of chiral and nonchiral LCs with and without polymer networks are described. LC gratings capable of switching under external stimuli such as light, electric and magnetic fields, heat, and chemical composition are discussed. The focus is on the materials, designs, applications, and future prospects of diffraction gratings using LC materials as active layers.
Catalytic Synthesis of 1,2,4,5‐Tetrasubstituted 1H‐Imidazole Derivatives: State of the Art
Authors: Rossi Renzo , Angelici Gaetano , Casotti Gianluca , Manzini Chiara , Lessi Marco
Published: December 2018

Tetrasubstituted 1H‐imidazoles are a large family of heteroarene derivatives that are known to include natural products isolated from marine sponges and synthetic compounds possessing a broad range of biological and pharmacological properties. Consequently, a great deal of attention has been given to the synthesis of these heteroarenes and reviews covering some synthetic aspects of this topic have been published in recent years. However, none of these reviews provides a comprehensive overview of the catalytic methods developed in the literature for the preparation of this important class of heteroarenes. This article aims to provide an updated critical picture of the catalytic processes reported in the literature up to the end of 2017 for the synthesis of 1,2,4,5‐tetrasubstituted 1H‐imidazoles illustrating these protocols and their characteristic features such as scope, efficiency, versatility, and limitations. The review also summarizes the mechanisms proposed for many of the reported processes.

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Accessing Enantiopure Endocyclic Sulfoximines Through Catalytic Cycloisomerization of Oxygenated Propargyl‐Sulfinamides
Authors: Cividino Pascale , Verrier Charlie , Philouze Christian , Carret Sébastien , Poisson Jean‐François
Published: December 2018

In this study, a novel strategy to access endocyclic sulfoximines in an enantiopure form is reported. The approach is based on a silver nitrate‐catalyzed cyclo‐isomerization reaction of oxygenated propargylic sulfinamides and provides efficiently 5‐membered endocyclic sulfoximines (isothiazole 1‐oxide). These new heterocyclic scaffolds can be isolated or directly converted into cyclic sulfinamides via Lewis acid‐mediated sulfur dealkylation reactions.

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Design of Atomically Precise Nanoscale Negative Differential Resistance Devices
Authors: Xiao Zhongcan , Ma Chuanxu , Huang Jingsong , Liang Liangbo , Lu Wenchang , Hong Kunlun , Sumpter Bobby G. , Li An‐Ping , Bernholc Jerzy
Published: December 2018

Downscaling device dimensions to the nanometer range raises significant challenges to traditional device design, due to potential current leakage across nanoscale dimensions and the need to maintain reproducibility while dealing with atomic‐scale components. Here, negative differential resistance (NDR) devices based on atomically precise graphene nanoribbons are investigated. The computational evaluation of the traditional double‐barrier resonant‐tunneling diode NDR structure uncovers important issues at the atomic scale, concerning the need to minimize the tunneling current between the leads while achieving high peak current. A new device structure consisting of multiple short segments that enables high current by the alignment of electronic levels across the segments while enlarging the tunneling distance between the leads is proposed. The proposed structure can be built with atomic precision using a scanning tunneling microscope (STM) tip during an intermediate stage in the synthesis of an armchair nanoribbon. An experimental evaluation of the band alignment at the interfaces and an STM image of the fabricated active part of the device are also presented. This combined theoretical–experimental approach opens a new avenue for the design of nanoscale devices with atomic precision.
3D Cellular Architecture Affects MicroRNA and Protein Cargo of Extracellular Vesicles
Authors: Rocha Sara , Carvalho Joana , Oliveira Patrícia , Voglstaetter Maren , Schvartz Domitille , Thomsen Andreas R. , Walter Nadia , Khanduri Richa , Sanchez Jean‐Charles , Keller Andreas , Oliveira Carla , Nazarenko Irina
Published: December 2018

The success of malignant tumors is conditioned by the intercellular communication between tumor cells and their microenvironment, with extracellular vesicles (EVs) acting as main mediators. While the value of 3D conditions to study tumor cells is well established, the impact of cellular architecture on EV content and function is not investigated yet. Here, a recently developed 3D cell culture microwell array is adapted for EV production and a comprehensive comparative analysis of biochemical features, RNA and proteomic profiles of EVs secreted by 2D vs 3D cultures of gastric cancer cells, is performed. 3D cultures are significantly more efficient in producing EVs than 2D cultures. Global upregulation of microRNAs and downregulation of proteins in 3D are observed, indicating their dynamic coregulation in response to cellular architecture, with the ADP‐ribosylation factor 6 signaling pathway significantly downregulated in 3D EVs. The data strengthen the biological relevance of cellular architecture for production and cargo of EVs.
Enhanced Temperature Stability and Defect Mechanism of BNT‐Based Lead‐Free Piezoceramics Investigated by a Quenching Process
Authors: Li Zhi‐Tao , Liu Hui , Thong Hao‐Cheng , Xu Ze , Zhang Mao‐Hua , Yin Jie , Li Jing‐Feng , Wang Ke , Chen Jun
Published: December 2018

Because of the environmental concerns of eliminating lead from piezoelectric products, bismuth‐based perovskite is becoming one of the most potential candidates. However, its relatively low thermal depolarization temperature (Td) is still an imperative obstacle hindering implementation of this material for practical application. Here, an enhanced temperature stability of 0.94(Bi0.5Na0.5)TiO3‐0.06BaTiO3 (BNTBT6) piezoceramics is reported, which can be obtained by the effective quenching process. Quenching process enhances the depolarization temperature to 136 °C, which is 40 °C higher than that of normal sintered samples. By using X‐ray photoelectron spectroscopy and electron paramagnetic resonance methods, it is revealed that oxygen vacancy may exist in the quenched samples and consequently pins the domain walls, resulting in significant enhancement of depolarization temperature. Temperature‐dependent dielectric, piezoelectric, and ferroelectric behaviors are measured as criteria to evidence the enhanced temperature stability.
Mortality among autoworkers manufacturing electronics in Huntsville, Alabama
Authors: DeBono Nathan , Kelly‐Reif Kaitlin , Richardson David , Keil Alex , Robinson Whitney , Troester Melissa , Marshall Stephen
Published: December 2018

Background

Workers raised concerns over suspected excesses of mortality at automotive electronics manufacturing facilities in Huntsville, Alabama.

Methods

A study of 4396 UAW members ever‐employed at Huntsville facilities between 1972 and 1993 was conducted with mortality follow‐up through 2016. Standardized Mortality Ratios (SMRs) were estimated using U.S. and Alabama reference rates.

Results

Relative to U.S. rates, there was a modest excess of all‐cause mortality among White female workers (SMR 1.08, 95%CI: 0.99‐1.18) and among all workers hired <1977 at the original plant building (SMR 1.10, 95%CI: 0.99‐1.22). There was excess nervous system disorder (SMR 1.24, 95%CI: 0.91‐1.65) and brain and nervous system cancer (SMR 1.31, 95%CI: 0.67‐2.28) mortality. Estimates for several causes of interest were imprecise.

Conclusions

All‐cause mortality estimates were greater than anticipated based on results from other UAW cohorts. The excess of nervous system disease mortality is consistent with other studies of electronics workers exposed to lead‐solder and chlorinated solvents.
Burkitt lymphoma in a patient with Kabuki syndrome carrying a novel KMT2D mutation
Authors: de Billy Emmanuel , Strocchio Luisa , Cacchione Antonella , Agolini Emanuele , Gnazzo Maria , Novelli Antonio , De Vito Rita , Capolino Rossella , Digilio Maria Cristina , Caruso Roberta , Mastronuzzi Angela , Locatelli Franco
Published: December 2018

Kabuki syndrome (KS) is an extremely rare genetic disorder, mainly caused by germline mutations at specific epigenetic modifier genes, including KMT2D. Because the tumor suppressor gene KMT2D is also frequently altered in many cancer types, it has been suggested that KS may predispose to the development of cancer. However, KS being a rare disorder, few data are available on the incidence of cancer in KS patients.

Here, we report the case of a 5‐year‐old boy affected by KS who developed Burkitt lymphoma (BL). Genetic analysis revealed the presence of a novel heterozygous mutation in the splice site of the intron 4 of KMT2D gene in both peripheral blood‐extracted DNA and tumour cells. In addition, the tumour sample of the patient was positive for the classical somatic chromosomal translocation t(8;14) involving the c‐MYC gene frequently identified in BL. We propose that the mutated KMT2D gene contributes to the development of both KS and BL observed in our patient and we suggest that strict surveillance must be performed in KS patients.
Non‐Hydrolytic β‐Lactam Antibiotic Fragmentation by l,d‐Transpeptidases and Serine β‐Lactamase Cysteine Variants
Authors: Lohans Christopher T. , Chan H. T. Henry , Malla Tika R. , Kumar Kiran , Kamps Jos J. A. G. , McArdle Darius J. B. , van Groesen Emma , de Munnik Mariska , Tooke Catherine L. , Spencer James , Paton Robert S. , Brem Jürgen , Schofield Christopher J.
Published: December 2018

Enzymes often use nucleophilic serine, threonine, and cysteine residues to achieve the same type of reaction; the underlying reasons for this are not understood. While bacterial d,d‐transpeptidases (penicillin‐binding proteins) employ a nucleophilic serine, l,d‐transpeptidases use a nucleophilic cysteine. The covalent complexes formed by l,d‐transpeptidases with some β‐lactam antibiotics undergo non‐hydrolytic fragmentation. This is not usually observed for penicillin‐binding proteins, or for the related serine β‐lactamases. Replacement of the nucleophilic serine of serine β‐lactamases with cysteine yields enzymes which fragment β‐lactams via a similar mechanism as the l,d‐transpeptidases, implying the different reaction outcomes are principally due to the formation of thioester versus ester intermediates. The results highlight fundamental differences in the reactivity of nucleophilic serine and cysteine enzymes, and imply new possibilities for the inhibition of nucleophilic enzymes.
Ion Mobility Mass Spectrometry Measures the Conformational Landscape of p27 and its Domains and how this is Modulated upon Interaction with Cdk2/cyclin A
Authors: Beveridge Rebecca , Migas Lukasz G. , Kriwacki Richard W. , Barran Perdita E.
Published: December 2018

Intrinsically disordered proteins have been reported to undergo disorder‐to‐order transitions upon binding to their partners in the cell. The extent of the ordering upon binding and the lack of order prior to binding is difficult to visualize with classical structure determination methods. Binding of p27 to the Cdk2/cyclin A complex is accompanied by partial folding of p27 in the KID domain, with the retention of dynamic behavior for function, particularly in the C‐terminal half of the protein. Herein, native ion mobility mass spectrometry (IM‐MS) is employed to measure the intrinsic dynamic properties of p27, both in isolation and within the trimeric complex with Cdk2/cyclin A. The trimeric Cdk2/cyclin A/p27‐KID complex possesses significant structural heterogeneity compared to Cdk2/cyclin A. These findings support the formation of a fuzzy complex in which both the N‐ and C‐termini of p27 interact with Cdk2/cyclin A in multiple, closely associated states.
A Metastable Crystalline Phase in Two‐Dimensional Metallic Oxide Nanoplates
Authors: Liu Cong , Zheng Lirong , Song Qian , Xue Zhenjie , Huang Chuanhui , Liu Lu , Qiao Xuezhi , Li Xiao , Liu Keyan , Wang Tie
Published: December 2018

A simple method was adopted in which ultrathin cerium oxide nanoplates (<1.4 nm) were synthesized to increase the surface atomic content, allowing transformation from a face‐centered cubic (fcc) phase to a body‐centered tetragonal (bct) phase. Three types of cerium oxide nanoparticles of different thicknesses (1.2 nm ultrathin nanoplates, 2.2 nm nanoplates, and 5.4 nm nanocubes) were examined using transmission electron microscopy and X‐ray diffraction. The metastable bct phase was observed only in ultrathin nanoplates. Thermodynamic energy analysis confirmed that the surface energy of the ultrathin nanoplates is the cause of the remarkable stabilization of the metastable bct phase. The mechanism of surface energy regulation can be expanded to other metallic oxides, thus providing a new means for manipulating and stabilizing novel materials under ambient conditions that otherwise would not be recovered.
The Color of the Elements: A Combined Experimental and Theoretical Electron Density Study of ScB2C2
Authors: Haas Christof D. , Fischer Andreas , Hauf Christoph , Wieser Christian , Schmidt Andreas P. , Eickerling Georg , Scheidt Ernst‐Wilhelm , Schiffmann Jan G. , Reckeweg Olaf , DiSalvo Francis J. , Rodewald Ute C. , Pöttgen Rainer , van Wüllen Leo , Scherer Wolfgang
Published: December 2018

The chemical or physical control parameters for the onset of superconductivity in MB2C2 hetero‐graphene materials are unclear. This is mainly due to the almost ubiquitous positional B/C disorder, rendering the description of real structures of borocarbides into one of the most challenging problems in materials science. We will show that high‐resolution X‐ray diffraction data provides all the essential information to decode even complex coloring problems due to B/C disorder. Electron density studies and subsequent analyses of the fine structure of the Laplacian of the electron density resolves the local electronic structure of ScB2C2 at sub‐atomic resolution and allows for an unequivocal identification of all atoms involved in the coloring scenario. This information could finally be used to identify the electron deficient character of the B/C layers in ScB2C2 and to synthesize the first bimetallic hetero‐metallocene with lithium and scandium atoms embedded in the pentagonal and heptagonal voids, respectively.
Kinetic Resolution of Tertiary Propargylic Alcohols by Enantioselective Cu−H‐Catalyzed Si−O Coupling
Authors: Seliger Jan , Dong Xichang , Oestreich Martin
Published: December 2018

A broad range of tertiary propargylic alcohols were kinetically resolved by catalyst‐controlled enantioselective silylation. This non‐enzymatic kinetic resolution is catalyzed by a Cu−H species and makes use of the commercially available precatalyst MesCu/(R,R)‐Ph‐BPE and a simple hydrosilane as the resolving reagent. Both alkyl,aryl‐ as well as dialkyl‐substituted propargylic alcohols participate, and especially high selectivity factors are achieved when the alkyne terminus carries a TIPS group, which also enables facile post‐functionalization in this position (s up to 207).