bluuebunny/crossref_metadata_2025_split huggingface dataset:
Respirable coal mine dust at surface mines, United States, 1982–2017
Authors: Doney Brent C. , Blackley David , Hale Janet M. , Halldin Cara , Kurth Laura , Syamlal Girija , Laney A. Scott 
Published: December 2019

AbstractBackgroundExposure to respirable coal mine dust can cause pneumoconiosis, an irreversible lung disease that can be debilitating. The mass concentration and quartz mass percent of respirable coal mine dust samples (annually, by occupation, by geographic region) from surface coal mines and surface facilities at U.S. underground mines during 1982‐2017 were summarized.MethodsMine Safety and Health Administration (MSHA) collected and analyzed data for respirable dust and a subset of the samples were analyzed for quartz content. We calculated the respirable dust and quartz concentration geometric mean, arithmetic mean, and percent of samples exceeding the respirable dust permissible exposure limit (PEL) of 2.0 mg/m3, and the average percent of quartz content in samples.ResultsThe geometric mean for 288 705 respirable dust samples was 0.17 mg/m3 with 1.6% of the samples exceeding the 2.0 mg/m3 PEL. Occupation‐specific geometric means for respirable dust in active mining areas were highest among drillers. The geometric mean for respirable dust was higher in central Appalachia compared to the rest of the U.S. The geometric mean for respirable quartz including 54 040 samples was 0.02 mg/m3 with 15.3% of these samples exceeding the applicable standard (PEL or reduced PEL). Occupation‐specific geometric means for respirable quartz were highest among drillers.ConclusionHigher concentrations of respirable dust or quartz in specific coal mining occupations, notably drilling occupations, and in certain U.S. regions, underscores the need for continued surveillance to identify workers at higher risk for pneumoconiosis.
Fetoplacental ratios in stillbirths and second trimester miscarriages
Authors: McPherson Elizabeth 
Published: December 2019

AbstractAn abnormal fetoplacental (F/P) ratio is a risk factor for poor pregnancy outcomes including fetal death, but studies of F/P ratio among stillbirths are limited. In the Wisconsin Stillbirth Service Program cohort of second and third trimester fetal deaths, 1,022 were at ≥24 weeks with data on fetal and placental weight. Comparison with data for viable infants of the same gestational ages (GAs) showed that the F/P ratio increases more rapidly with GA for stillbirths than for viable infants. While placentas of stillborn infants are small at all GA, weights of deceased fetuses are lowest early in the second trimester, becoming nearly normal by term. Excess high F/P ratios are noted at all GAs, increasing toward term, while low ratios are frequent at early gestation but rare near term. Analysis by cause of death shows that F/P ratios are markedly elevated for placental and maternal causes (about 50% above the 90th centile), somewhat elevated for cord accidents, non‐hydropic fetal, and unknown causes (about 1/3 above the 90th centile), and variable with 40% below the 10th centile for hydropic stillbirths. Across all causes and GAs, placental weights are more abnormal than fetal weights, suggesting that diminished placental function may contribute to fetal demise even when non‐placental causes (e.g., premature membrane rupture, cord accidents, and chromosomal disorders) are identified. About half of all stillbirths have abnormal F/P ratios, suggesting that improvements in prenatal assessment of placental size and function might aid in identifying pregnancies at risk for demise; unfortunately, therapeutic options for ongoing pregnancies with diminished placental function remain limited.
Current state of research on non‐human primate models of Alzheimer’s disease
Authors: Li Hong‐Wei , Zhang Ling , Qin Chuan 
Published: December 2019

AbstractWith the increasingly serious aging of the global population, dementia has already become a severe clinical challenge on a global scale. Dementia caused by Alzheimer's disease (AD) is the most common form of dementia observed in the elderly, but its pathogenetic mechanism has still not been fully elucidated. Furthermore, no effective treatment strategy has been developed to date, despite considerable efforts. This can be mainly attributed to the paucity of animal models of AD that are sufficiently similar to humans. Among the presently established animal models, non‐human primates share the closest relationship with humans, and their neural anatomy and neurobiology share highly similar characteristics with those of humans. Thus, there is no doubt that these play an irreplaceable role in AD research. Considering this, the present literature on non‐human primate models of AD was reviewed to provide a theoretical basis for future research.
Biomimetic Hydrogenation Catalyzed by a Manganese Model of [Fe]‐Hydrogenase
Authors: Pan Hui‐Jie , Hu Xile 
Published: December 2019

Abstract[Fe]‐hydrogenase is an efficient biological hydrogenation catalyst. Despite intense research, Fe complexes mimicking the active site of [Fe]‐hydrogenase have not achieved turnovers in hydrogenation reactions. Herein, we describe the design and development of a manganese(I) mimic of [Fe]‐hydrogenase. This complex exhibits the highest activity and broadest scope in catalytic hydrogenation among known mimics. Thanks to its biomimetic nature, the complex exhibits unique activity in the hydrogenation of compounds analogous to methenyl‐H4MPT+, the natural substrate of [Fe]‐hydrogenase. This activity enables asymmetric relay hydrogenation of benzoxazinones and benzoxazines, involving the hydrogenation of a chiral hydride transfer agent using our catalyst coupled to Lewis acid‐catalyzed hydride transfer from this agent to the substrates.
Regulating the Coordination Environment of MOF‐Templated Single‐Atom Nickel Electrocatalysts for Boosting CO2 Reduction
Authors: Gong Yun‐Nan , Jiao Long , Qian Yunyang , Pan Chun‐Yang , Zheng Lirong , Cai Xuechao , Liu Bo , Yu Shu‐Hong , Jiang Hai‐Long 
Published: December 2019

AbstractThe general synthesis and control of the coordination environment of single‐atom catalysts (SACs) remains a great challenge. Herein, a general host–guest cooperative protection strategy has been developed to construct SACs by introducing polypyrrole (PPy) into a bimetallic metal–organic framework. As an example, the introduction of Mg2+ in MgNi‐MOF‐74 extends the distance between adjacent Ni atoms; the PPy guests serve as N source to stabilize the isolated Ni atoms during pyrolysis. As a result, a series of single‐atom Ni catalysts (named NiSA‐Nx‐C) with different N coordination numbers have been fabricated by controlling the pyrolysis temperature. Significantly, the NiSA‐N2‐C catalyst, with the lowest N coordination number, achieves high CO Faradaic efficiency (98 %) and turnover frequency (1622 h−1), far superior to those of NiSA‐N3‐C and NiSA‐N4‐C, in electrocatalytic CO2 reduction. Theoretical calculations reveal that the low N coordination number of single‐atom Ni sites in NiSA‐N2‐C is favorable to the formation of COOH* intermediate and thus accounts for its superior activity.
Highly Enantioselective Construction of Strained Spiro[2,3]hexanes through a Michael Addition/Ring Expansion/Cyclization Cascade
Authors: Zhao Chuan‐Gang , Feng Zhi‐Tao , Xu Guo‐Qiang , Gao Ang , Chen Jing‐Wei , Wang Zhu‐Yin , Xu Peng‐Fei 
Published: December 2019

AbstractWe herein report a general organocatalytic enantioselective strategy for the construction of highly strained spiro[2,3]hexane skeletons from methylenecyclopropanes and a broad selection of α,β‐unsaturated aldehydes. The reaction proceeds through a Michael addition followed by ring expansion of methylenecyclopropanes and nucleophilic attack of an enamine to realize the construction of spiro[2,3]hexanes. Key to the success of this approach are the utilization of an electron‐deficient difluoro‐substituted secondary amine catalyst and the intrinsic reactivity of methylenecyclopropanes.
Emergent Deep‐Ultraviolet Nonlinear Optical Candidates
Authors: Mutailipu Miriding , Pan Shilie 
Published: December 2019

AbstractAdvances in the generation of coherent lasers at wavelengths below 200 nm as well as the associated equipment and technologies have greatly spurred the development of nonlinear optical (NLO) materials that are capable of phase‐matching in the deep‐ultraviolet (deep‐UV) spectral regions. However, few crystals can meet the technical demands, and studies to date have focused mainly on finding the next competitive candidates. Consequently, several crystals have emerged that hold great potential for the production of deep‐UV harmonic coherent light, which benefit from newly developed systems with novel NLO‐active units and chromophores. This Review provides a comprehensive overview of the developments of emergent candidates in the field of deep‐UV NLO materials, discussing the recent efforts and active advances in the search for superior systems and in understanding their structure–property relationships. The intention is to provide a clear perspective on the current emergent deep‐UV NLO candidates, and to accelerate the discovery of next candidates with high performances to meet the urgent demands.
Functional Nanoparticles with a Reducible Tetrasulfide Motif to Upregulate mRNA Translation and Enhance Transfection in Hard‐to‐Transfect Cells
Authors: Wang Yue , Tang Jie , Yang Yannan , Song Hao , Fu Jianye , Gu Zhengying , Yu Chengzhong 
Published: December 2019

AbstractEffective messenger RNA (mRNA) transfection in hard‐to‐transfect cells delivered by vectors is a long‐standing challenge. Now it is hypothesized that the high intracellular glutathione level is associated with suppressed mRNA translation. This theory leads to a new design principle of next‐generation mRNA vectors: nanoparticles with glutathione depletion chemistry upregulate mRNA translation and enhance transfection, which is beneficial for mRNA delivery in hard‐to‐transfect cells in vitro and in vivo.
Effect of water aging on the mechanical properties of flax fiber/bio‐based resin composites
Authors: Kollia Evgenia , Saridaki Xrisoula , Karagiannis Dimitrios , Kostopoulos Vassilis 
Published: December 2019

ABSTRACTPresent work investigates the effect of hydrothermal aging of flax fiber‐reinforced bio‐based epoxy resin laminates on the mechanical and thermomechanical properties of the composites. Three different types of bio‐based resins were used. Plates reinforced with eight layers plain weave flax fibers of 150 g/m2, manufactured using Resin Transfer Molding (RTM), compression molding or autoclave technique depends on type of the resin. One dimensional Fickian behavior shows a good fitting to the experimental data derived from weight measurements. The water uptake at the equilibrium state in the case of 60 °C temperature was slightly greater than that at 40 °C. The mechanical properties after hydrothermal aging show a significant reduction and do not return to their initial values even after the drying process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48787.
Development and full validation of an LC–MS/MS methodology to quantify capmatinib (INC280) following intragastric administration to rats
Authors: Fan Xiaoguang , Yang Guanghu , Cui Wenjuan , Liu Qin , Zhang Zhaolong , Zhang Zhikun 
Published: December 2019

AbstractA highly sensitive, specific and simple LC–MS/MS method for quantification of capmatinib (INC280) in rat plasma was presented. The LC–MS/MS method was validated in terms of specificity and selectivity, linearity, accuracy and precision, matrix effect, extraction recovery, dilution integrity, carryover and stability as per the US Food and Drug Administration's bioanalytical method validation guideline. The validated assay was applied for quantification of capmatinib from a pharmacokinetic study in rats following oral administration at the doses of 1.0, 3.0 and 9.0 mg/kg. The calibration curve ranges from 1 to 2000 ng/ml with desirable linearity and r2 > 0.99. The intra‐ and inter‐batch accuracies were within 99.24–103.59 and 97.76–102.83% with coefficients of variation 5.08–7.36 and 3.18–4.99%, respectively. No significant interference was observed by endogenous peak at the retention time of capmatinib and IS. The assay was free from any matrix effect and showed precise recovery across the calibration curve range, and samples were stable under all experimental conditions. The validated assay was successfully applied to analyze plasma samples of pharmacokinetic study in rat to determine the concentration of capmatinib. In summary, a novel method for analyzing capmatinib in rat plasma has been successfully validated and is now being utilized for quantification of capmatinib from pre‐clinical studies.
The relationship between the volume of clinical presentation exposures, hours, and student self‐rated confidence
Authors: Lafave Mark R. , Yeo Michelle 
Published: December 2019

AbstractIntroductionThe relationship between student's self‐rated confidence and competency development is not clearly understood. The purpose of this study was to explore the relationship between confidence, the total number of practical hours, and the volume of clinical presentation (CP) exposures.MethodsConfidence, practical hours, and the volume of CP exposures were collected over the last two years for thirteen undergraduate athletic therapy students, and a Spearman rho and Wilcoxon rank test were employed.ResultsConfidence grew steadily throughout the two years. Statistically significant relationships emerged between confidence and the volume of CP exposures at various time points.DiscussionThere were three significant findings in this study: (a) Confidence grew steadily over the course of a two‐year period; (b) the volume of CP exposures could influence confidence growth and, thus, may also be a factor to influence competency development over time; and (c) time alone did not influence the growth in confidence.
Synthesis of Iridium Nanocatalysts for Water Oxidation in Acid: Effect of the Surfactant
Authors: Arminio‐Ravelo José Alejandro , Quinson Jonathan , Pedersen Mads A. , Kirkensgaard Jacob J. K. , Arenz Matthias , Escudero‐Escribano María 
Published: December 2019

AbstractProton exchange membrane water electrolysers are very promising renewable energy conversion devices to produce hydrogen from sustainable feedstocks. These devices are mainly limited by the sluggish kinetics of the oxygen evolution reaction (OER). Therefore, efficient catalysts in acidic media that allow operating at low overpotential are necessary. Ir‐based nanoparticles are both active and stable for the OER. Surfactants are widely used in the preparation of nanoparticle colloids. A severe drawback for catalysis is the need to remove surfactants by typically costly, hazardous, time and/or energy consuming steps. Herein we present a modified approach of the polyol synthesis that consists of a simple surfactant‐free and NaOH‐free synthesis of Ir nanoparticles in ethylene glycol leading to colloidal nanoparticles of ca. 2.5 nm in diameter. The benefits and drawbacks of the surfactant‐free synthesis are illustrated by comparison with commercial Ir black nanoparticles and Ir nanoparticles obtained using surfactant for the electrocatalytic OER in acidic media.
Influence of Liquid Solutions on the Ionic Conductivity of Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolytes
Authors: Huang Yi , Jiang Yue , Zhou Yuxi , Hu Zhiwei , Zhu Xiaohong 
Published: December 2019

AbstractHydrothermal synthesis is used to successfully prepare Li1.3Al0.3Ti1.7(PO4)3 (LATP) solid electrolytes with high lithium‐ion conductivity, typically being 0.213 mS cm−1. The best calcination and sintering temperatures are optimized to be 900 and 1075 °C, respectively. The solvent effects on conductivity and microstructure of LATP in water, ethanol and acetone are investigated by using impedance spectroscopy and scanning electron microscopy. The conductivity of LATP in water reaches 1.167 mS cm−1. In ethanol, the conductivity of LATP is 0.464 mS cm−1. There is no significant change in acetone. The structural stability of LATP after immersing in liquid solutions is verified by X‐ray diffraction and Raman spectroscopy. It is found by infrared spectroscopy that the change in conductivity is related to the adsorbed OH bond, and the reason for the increase in conductivity is discussed.
Sulfur‐Rich Molybdenum Sulfide as an Anode Coating to Improve Performance of Lithium Metal Batteries
Authors: Meyerson Melissa L. , Pandit Anish H. , Weeks Jason A. , Mabayoje Oluwaniyi , Celio Hugo , Stephens Ryan M. , Heller Adam , Mullins C. Buddie 
Published: December 2019

AbstractIn lithium metal batteries (LMBs), the reaction between metallic Li and organic electrolytes consumes both Li and electrolyte, while the inhomogeneity of the resulting solid‐electrolyte interphase (SEI) contributes to inhomogeneous Li deposition. An artificial SEI, made by coating the Li surface with an electronically insulating material, can mitigate problems caused by uncontrolled SEI formation by 1) decreasing reduction of the electrolyte on the surface, and 2) increasing the uniformity of the Li+ flux to the electrode surface, thereby mitigating dendrite growth. In this work, we present a technique for coating the surface of LMB electrodes with sulfur‐rich molybdenum sulfide. This coating acts as an artificial SEI, which improves the coulombic efficiency and cycling stability of the LMBs by improving the reaction kinetics and decreasing the surface area of the exposed Li.
Scholl‐Type Cycloheptatriene Ring Closure of 1,4,9,12‐Tetraarylfenestrindanes: Reactivity and Selectivity in the Construction of Fenestrane‐Based Polyaromatic Saddles
Authors: Wong Wai‐Shing , Lau Wing‐Wa , Li Yuke , Liu Zhifeng , Kuck Dietmar , Chow Hak‐Fun 
Published: December 2019

AbstractThe Scholl‐type cyclodehydrogenation, generating up to four cycloheptatriene rings around a fenestrindane core, leads to novel, saddle‐shaped polyaromatic hydrocarbon derivatives. In this article, we present the results of in‐depth experimental and computational work on the oxidative cyclization of various 1,4,9,12‐tetraarylfenestrindanes. In particular, the kinetic control of the four‐step cyclization of the electronically activated tetrakis(3,4‐dimethoxyphenyl) derivative is elucidated. The reasons for the exclusive emergence of one single among the three possible doubly cyclized intermediates and for the nonappearance of the singly and triply cyclized intermediates are clarified. In addition, the origin of the concomitant bridgehead hydroxylation is studied. The reactivity of a set of fifteen symmetrically and unsymmetrically substituted 1,4,9,12‐tetraarylfenestrindanes towards Scholl‐type cyclodehydrogenation is presented, pinpointing the structural factors that underlie this reaction and demonstrating the potential and limitations of this synthetic approach. A particularly surprising finding of this study is that the electronically nonactivated 1,4,9,12‐tetraphenylfenestrindane can also undergo the fourfold Scholl‐type cyclization process and can be transformed into the parent saddle hydrocarbon.
Structural Insight into Binary Protein Metal–Organic Frameworks with Ferritin Nanocages as Linkers and Nickel Clusters as Nodes
Authors: Gu Chunkai , Chen Hai , Wang Yingjie , Zhang Tuo , Wang Hongfei , Zhao Guanghua 
Published: December 2019

AbstractMetal–organic frameworks (MOFs) hold great promise for numerous applications. However, proteins, carriers of biological functions in living systems, have not yet been fully explored as building blocks for the construction of MOFs. This work presents a strategy for the fabrication of binary MOFs. Considering octahedral ferritin symmetry, four His2 (His–His) motifs were first incorporated into the exterior surface of a ferritin nanocage near each C4 channel, yielding protein linkers with multiple metal‐binding sites (bisH‐SF). Secondly, by adding nickel ions to bisH‐SF solutions triggers the self‐assembly of ferritin nanocages into a porous 3D crystalline MOF with designed protein lattice, where two adjacent ferritin molecules along the C4 symmetry axes are bridged by four dinuclear or tetranuclear nickel clusters depending on Ni2+ concentration. This work provides a simple approach for precise control over a binary protein–metal crystalline framework, and the resulting MOFs exhibited inherent ferroxidase activity and peroxidase‐like catalytic activity.
Co‐generation of Ammonia and H2 from H2O Vapor and N2 Using a Membrane Electrode Assembly
Authors: Kugler Kurt , Kriescher Stefanie M. A. , Giela Martin , Hosseiny Schwan , Thimm Kristof , Wessling Matthias 
Published: December 2019

AbstractThe direct electrochemical synthesis of NH3 from nitrogen and water vapor without the use of a fossil carbon source is highly desired. This synthesis is a viable option to store energy and produce fertilizer precursors. Here, a new Pt‐free membrane electrode assembly is presented. An electrochemical membrane reactor demonstrates the feasibility of co‐generating NH3 and H2 directly from nitrogen and water vapor at ambient conditions. An unprecedented high NH3‐specific current efficiency of up to 27.5% using Ti as cathodic catalyst is reported. The co‐generation can be tuned by the balance of process parameters.
ERK inhibition effectively overcomes acquired resistance of epidermal growth factor receptor‐mutant non–small cell lung cancer cells to osimertinib
Authors: Li Yiting , Zang Hongjing , Qian Guoqing , Owonikoko Taofeek K. , Ramalingam Suresh R. , Sun Shi‐Yong 
Published: December 2019

BackgroundOsimertinib (AZD9291), a third‐generation, mutation‐selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (EGFR‐TKI), is an approved drug for patients who have non–small cell lung cancer (NSCLC) with activating EGFR mutations or those harboring a resistant T790M mutation. Unfortunately, all patients eventually relapse and develop resistance to osimertinib. The current study addressed whether ERK inhibition exerts effects similar to those produced by MEK inhibition in overcoming acquired resistance to osimertinib.MethodsDrug effects on cell and tumor growth were assessed by measuring cell number alterations and colony formation in vitro and with xenografts in nude mice in vivo. Apoptosis was assessed with annexin V/flow cytometry and protein cleavage. Protein alterations in cells were detected with Western blot analysis. Gene overexpression and knockout were achieved with lentiviral infection and CRISPR/Cas9, respectively.ResultsThe combination of osimertinib with an ERK inhibitor synergistically decreased the survival of osimertinib‐resistant cell lines with enhanced induction of apoptosis and effectively inhibited the growth of osimertinib‐resistant xenografts in nude mice. Moreover, the combination of an MEK or ERK inhibitor with a first‐generation (eg, erlotinib) or second‐generation (eg, afatinib) EGFR‐TKI also very effectively inhibited the growth of osimertinib‐resistant cells in vitro and of tumors in vivo, although these cell lines were cross‐resistant to first‐generation or second‐generation EGFR‐TKIs.ConclusionsThe current findings emphasize the importance of targeting MEK/ERK signaling in maintaining the long‐term benefit of osimertinib through overcoming acquired resistance to osimertinib, warranting further investigation of this therapeutic strategy to improve the therapeutic efficacy of osimertinib in the clinic.