bluuebunny/crossref_metadata_2025_split huggingface dataset:
Species characteristics affect local extinctions
Authors: Zettlemoyer Meredith A. , McKenna Duane D. , Lau Jennifer A. 
Published: April 2019

Premise of the StudyHuman activities threaten thousands of species with extinction. However, it remains difficult to predict extinction risk for many vulnerable species. Species traits, species characteristics such as rarity or habitat use, and phylogenetic patterns are associated with responses to anthropogenic environmental change and may help predict likelihood of extinction.MethodsWe used historical botanical data from Kalamazoo County, Michigan,USA, to examine whether species traits (growth form, life history, nitrogen‐fixation, photosynthetic pathway), species characteristics (community association, species origin, range edge, habitat specialization, rarity), or phylogenetic relatedness explain local species loss at the county level.Key ResultsAcross Kalamazoo County, prairie species, species at the edge of their native range, regionally rare species, and habitat specialists were most likely to become locally extinct. Prairie species experienced the highest local extinction rates of any habitat type, and among prairie species, regionally rare and specialist species were most vulnerable to loss. We found no evidence for a phylogenetic pattern in plant extinctions.ConclusionsOur study illustrates the value of historical datasets for understanding and potentially predicting biodiversity loss. Not surprisingly, rare, specialist species occupying threatened habitats are most at risk of local extinction. As a result, identifying mechanisms to conserve or restore rare or declining species and preventing further habitat destruction may be the most effective strategies for reducing future extinction.
Synthetic copolymer (AM/AMPS/DMDAAC/SSS) as rheology modifier and fluid loss additive at HTHP for water‐based drilling fluids
Authors: Huang Yuming , Zhang Dingyu , Zheng Wenlong 
Published: April 2019

ABSTRACTIn the petroleum industry, high temperature and high pressure (HTHP) would dramatically worsen rheological properties and increase fluid loss volumes of drilling fluids. Synthetic polymer as an indispensable additive has attracted more and more attention recently. In this article, a new copolymer (named AADS) of 2‐acrylamide‐2‐methylpropanesulfonic acid, acrylamide, dimethyl diallyl ammonium chloride, and sodium styrene sulfonate was synthesized through aqueous solution polymerization. The chemical structure of the copolymer was characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. Moreover, its thermal stability was simultaneously analyzed using a differential scanning calorimetry. The results showed that the synthetic polymer contained all the designed functional groups, and its structure was consistent to the desired one. Under contamination of sodium chloride, AADS solution maintained relatively high viscosity in high concentration brine, showing a good antisalt capacity. Furthermore, the effect of AADS content and temperature on rheological behavior and fluid loss volume of the water‐based drilling fluid (WBDF) containing the synthesized product were investigated according to the American Petroleum Institute standard. Results showed that the rheological and filtration properties of the prepared WBDF were improved with the increase in the AADS concentration before and after the thermal aging test. In addition, in the temperature range of 80–240 °C, a reversible rheological behavior was observed during the heating–cooling process, and the HTHP fluid loss was controlled within 22.5 mL, suggesting that the copolymer AADS was suitable for making WBDF s with high temperature resistance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47813.
Aggregation‐Induced Emission‐Active 1,4‐Dihydropyridine‐Based Dual‐Phase Fluorescent Sensor with Multiple Functions
Authors: Zhou Yibin , Chen Yating , Duan Chong , Zeng Lintao , Liu Miaochang , Zhou Yunbing , Gao Wenxia , Huang Xiaobo , Wu Huayue 
Published: April 2019

AbstractA N‐2‐phenylethyl‐substituted 1,4‐dihydropyridine derivative (NDHP) containing 5,5‐dimethylcyclohexane‐1,3‐dione and naphthylethylene was designed and synthesized. NDHP acts as a multifunctional fluorescent sensor in dual phases. The crystal structure analysis confirms that the NDHP molecules have highly twisted conformations. The twisted conformation results in aggregation‐induced emission properties and solid‐state emission, by restricting the intramolecular free rotation in the aggregated or solid state. In the solid state, NDHP exhibits reversible mechanochromic properties as a result of the transition between the amorphous and crystalline states. NDHP also exhibits a rare phenomenon of acid‐fumed solid‐state emission enhancement owing to the change in packing mode from a zigzag arrangement to J‐aggregation. The solid‐state stimuli‐responsive fluorescence switching is applied to realize a rewritable optical recording media and a multiple output combinational logic system. In solution, NDHP shows a selective fluorescence response for environmentally harmful Hg2+, with a limit of detection of 2.7 nm. This results from the “turn‐on” responsive behavior owing to the Hg2+‐triggered aggregation of the NDHP molecules. NDHP is also used in the imaging of intracellular Hg2+ in HeLa cells. These findings provide a feasible and attractive route for developing multifunctional fluorescent sensors for use in dual phases.
Disruption of sleep architecture in Prevotella enterotype of patients with obstructive sleep apnea‐hypopnea syndrome
Authors: Ko Chih‐Yuan , Fan Ji‐Mim , Hu An‐Ke , Su Huan‐Zhang , Yang Jiao‐Hong , Huang Li‐Mei , Yan Fu‐Rong , Zhang Hua‐Ping , Zeng Yi‐Ming 
Published: April 2019

AbstractIntroductionIntermittent hypoxia and sleep fragmentation are critical pathophysiological processes involved in obstructive sleep apnea‐hypopnea syndrome (OSAHS). Those manifestations independently affect similar brain regions and contribute to OSAHS‐related comorbidities that are known to be related to the host gut alteration microbiota. We hypothesized that gut microbiota disruption may cross talk the brain function via the microbiota–gut–brain axis. Thus, we aim to survey enterotypes and polysomnographic data of patients with OSAHS.MethodsSubjects were diagnosed by polysomnography, from whom fecal samples were obtained and analyzed for the microbiome composition by variable regions 3–4 of 16S rRNA pyrosequencing and bioinformatic analyses. We examined the fasting levels of interleukin‐6 and tumor necrosis factor‐alpha of all subjects.ResultsThree enterotypes Bacteroides, Ruminococcus, and Prevotella were identified in patients with OSAHS. Arousal‐related parameters or sleep stages are significantly disrupted in apnea‐hypopnea index (AHI) ≥15 patients with Prevotella enterotype; further analysis this enterotype subjects, obstructive, central, and mixed apnea indices, and mean heart rate are also significantly elevated in AHI ≥15 patients. However, blood cytokines levels of all subjects were not significantly different.ConclusionsThis study indicates the possibility of pathophysiological interplay between enterotypes and sleeps structure disruption in sleep apnea through a microbiota–gut–brain axis and offers some new insight toward the pathogenesis of OSAHS.
Mainstreaming public–private partnership in national development: How ready is Ghana?
Authors: Ahenkan Albert 
Published: April 2019

AbstractPublic–private partnership (PPP) is a relatively new development paradigm in most developing countries. In an increasingly competitive global environment, governments around the world are focusing on new ways to finance development projects, build infrastructure, and provide social services to their citizens. This paper examines the challenges and the enabling environment for PPP mainstreaming in Ghana's development agenda. The study reviewed critical literature pertaining to prospects and challenges of PPPs across the world and critical success factors and challenges. The study was spiced by data generated through in‐depth interviews with experts on PPPs in Ghana. The paper reveals that implementation of PPPs in Ghana could be fraught with a number of challenges including regulatory frameworks, weak institutions, weak technical expertise, political will, bureaucracy, poor maintenance culture, contracting, negotiation challenges, and risk sharing and corruption. These challenges are complex in nature and require concerted effort and enabling environment to address them. There is the need for a clear regulatory framework and institutional capacity building to enable Ministries, Departments and Agencies and Metropolitan, Municipal and District Assemblies to effectively handle the PPP processes in Ghana.
TLR4 increases the stemness and is highly expressed in relapsed human hepatocellular carcinoma
Authors: Zhou Shuang , Du Renle , Wang Zhenglu , Shen Wenzhi , Gao Ruifang , Jiang Shan , Fang Yan , Shi Yuzhi , Chang Antao , Liu Lei , Liu Chenghu , Li Na , Xiang Rong 
Published: April 2019

AbstractToll‐like receptor 4 (TLR4) plays an essential role in cancer progress. Here, we find that the expression of TLR4 in relapsed human hepatocellular carcinoma (HCC) clinical samples is higher than that in the non‐relapsed ones, which leads us to explore the role of TLR4 in cancer stemness. We reported that TLR4‐AKT signaling pathway was activated by lipopolysaccharides (LPS) in HCC cell lines to enhance the cancer stemness capacity, which was reflected by the increased percentage of CD133+CD49f+ population and side population, enhanced sphere formation, and the upregulation of stemness marker gene‐SOX2. Downregulation of SOX2 attenuated the enhanced HCC stemness induced by LPS, indicating SOX2 as a downstream mediator of LPS‐TLR4 signaling. The role of LPS‐TLR4 signaling in inducing HCC stemness was further confirmed by tumor xenograft experiment in vivo. Taken together, our findings provide a novel therapeutic target to prevent the recurrence of HCC.
Synthesis, Antimicrobial Activities, and Molecular Docking Studies of Dihydrotriazine Derivatives Bearing a Quinoline Moiety
Authors: Bai Xueqian , Chen Ying , Liu Zhe , Zhang Linhao , Zhang Tianyi , Feng Bo 
Published: April 2019

AbstractIn this article, three series of dihydrotriazine derivatives bearing a quinoline moiety (5a, 5b, 8a–8c, and 9a–9m) have been designed, synthesized, and evaluated as antibacterial agents. Compounds 8a–8c were found to be the most potent of all of the compounds tested with an MIC value of 1 μg/mL against several Gram‐positive (S. aureus 4220 and MRSA CCARM 3506) and Gram‐negative (E. coli 1924) strains of bacteria. In addition, 3‐[4‐amino‐6‐(phenethylamino)‐2,5‐dihydro‐1,3,5‐triazin‐2‐yl)‐6‐[(3‐chlorobenzyl)oxy]quinolin‐2‐ol (8a) showed potent inhibitory activity (MIC=2 μg/mL) against Pseudomonas aeruginosa 2742, indicating that its antibacterial spectrum is similar to those of the positive controls gatifloxacin and moxifloxacin. Structure‐activity relationships (SAR) analyses and docking studies implicated the dihydrotriazine group in increasing the antimicrobial potency of the quinoline compounds. In vitro enzyme study implied that compound 8a also displayed DHFR inhibition.
MiR‐19b‐3p regulates osteogenic differentiation of PDGFRα+ muscle cells by specifically targeting PTEN
Authors: Zhu Yong , Long Hai‐Tao , Zeng Lei , Tang Yi‐fu , Zhao Rui‐bo , Lin Zhang‐yuan , Zhao Shu‐shan , Cheng Liang 
Published: April 2019

AbstractHeterotopic ossification (HO) is a common disturbing complication of intra‐articular fractures. Its prevention and treatment are still difficult as its pathogenesis is unclear. It was reported that PDGFRα+ muscle cells in skeletal muscle may participate in the formation of HO; however, the specific mechanism is still unknown. This study investigated the function of miR‐19b‐3p in osteogenic differentiation of PDGFRα+ muscle cells. MiR‐19b‐3p was upregulated during PDGFRα+ muscle cell osteogenic differentiation. The exogenous expression of miR‐19b‐3p led to an increase in osteogenic marker gene transcription and translation during the osteogenic differentiation of PDGFRα+ muscle cells. Furthermore, both alkaline phosphatase and alizarin red staining increased in miR‐19b‐3p mimic transfected cells. Over‐expression of miR‐19b‐3p led to the down‐regulation of gene of phosphate and tension homology deleted on chromosome ten (PTEN). Additionally, the dual luciferase reporter assay demonstrated that PTEN was a direct target of miR‐19b‐3p. The increase of osteocalcin, osteopontin, and Runt‐related transcription factor 2 protein levels induced by ectopic miR‐19b‐3p expression could be partially reversed by PTEN over‐expression. In conclusion, our results suggested that miR‐19b‐3p may be a promising target in inhibiting PDGFRα+ muscle cell osteogenic differentiation and treatment of HO.
The absorption of apolipoprotein E by damaged neurons facilitates neuronal repair
Authors: Chen Min , Xie Ming , Peng Chao , Long Shuangqi 
Published: April 2019

AbstractTraumatic brain injury (TBI) is one of the common diseases diagnosed in departments of neurosurgery. Apolipoprotein E (apoE) can improve the prognosis of TBI. In this study, we aimed to explore the effect of apoE in mechanically damaging neurons as well as its underlying molecular mechanism. Western blot analysis and immunofluorescence assay was performed to detect the expressions of associated proteins. The expressions of apoE, p38, and phosphorylation of P38 were increased in mechanically injured neurons compared with those of the non‐injured ones. Neurons transfected into silencing apoE had no clear difference in the expression of apoE between injured and non‐injured neurons. However, in the injured neurons, silencing apoE could significantly decrease apoE and p‐P38 expressions. Oligodendrocytes were cultured in the medium collected from mechanically damaged si‐apoE neurons. Furthermore, we found that mechanically injured si‐apoE neurons could absorb the secreted apoE from the oligodendrocyte medium of the injured si‐apoE‐neuron, along with increasing of p‐P38 expression at 24 h. The p38 MAPK inhibitor BIRB 796 almost did not affect the apoE expression at 24 h, but significantly reduced the p‐P38 level at 24 and 72 h in injured si‐apoE neurons cultured with oligodendrocyte medium of the injured si‐apoE‐neurons. Moreover, our result showed that neuronal repair effects in normal neurobasal medium (lowest levels of apoE and p‐P38) and BIRB 796 medium (low level of p‐P38) were more slow than those in the oligodendrocyte medium of the injured si‐apoE‐neurons. To conclude, our data demonstrated that mechanical injury of neurons stimulated oligodendrocytes to secrete apoE. The injured neurons could absorb secreted apoE. The expression of apoE contributed to the activation of p38 MAPK, which facilitated neuron repair.
Rational Redesign of a Regioselective Hydroformylation Catalyst for 3‐Butenoic Acid by Supramolecular Substrate Orientation
Authors: Bai Shao‐Tao , Sinha Vivek , Kluwer Alexander M. , Linnebank Pim R. , Abiri Zohar , de Bruin Bas , Reek Joost N. H. 
Published: April 2019

AbstractRational design of ligands for regioselective transformations is one of the long pursuing targets in the field of transition metal catalysis. In the current contribution, we report OrthoDIMphos (L2), a ligand that was designed for regioselective hydroformylation of 3‐butenoic acid and its derivatives. The previously reported ParaDIMphos (L1) based hydroformylation catalyst was very selectively producing the linear aldehyde when substrates were bound in its pocket via hydrogen bonding. However, the distance between the binding site and the rhodium center was too large to also address 3‐butenoic acid and its derivatives. We therefore designed OrthoDIMphos (L2) as new ligand which has a shorter distance between the DIM‐receptor and the catalytic center. The OrthoDIMphos (L2) based catalyst displays high regioselectivity in the hydroformylation of 3‐butenoic acid and challenging internal alkene analogue (l/b up to 84, TON up to 630), which cannot be achieved with the ParaDIMphos (L1) catalyst. Detailed studies show that the OrthoDIMphos (L2) based catalyst forms a dimeric structure, in which the two ligands coordinate to two different rhodium metals. Substrate binding to the DIM‐receptor is required to break up the dimeric structure, and as only the monomeric analogue is a selective catalyst, the outcome of the reaction is dependent on substrate concentration used in catalysis.
Metal Silicide Nanosphere Decorated Carbon‐Rich Polymer‐Derived Ceramics: Bifunctional Electrocatalysts towards Oxygen and their Application in Anion Exchange Membrane Fuel Cells
Authors: Abinaya S. , Moni Prabu , Parthiban V. , Sahu Akhila Kumar , Wilhelm Michaela 
Published: April 2019

AbstractThe current hindrance in the commercialization of electrochemical devices such as fuel cells and metal–air batteries is the high cost and poor stability of widely employed noble‐metal‐based electrocatalysts. In this report, a new intermetallic nickel/cobalt silicide‐decorated carbon‐rich silica‐based ceramic composites (Co/SiOC or Ni/SiOC) were successfully synthesized as alternative bifunctional electrocatalysts. The oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) kinetics of the prepared composite materials were evaluated by electrochemical characterization. Co/SiOC exhibited more positive ORR kinetics with the onset potential of 0.87 V vs. RHE compared to that of Ni/SiOC, which is slightly lower compared to Pt/C. Conversely, Ni/SiOC exhibits a 50 mV more positive OER onset potential compared to Co/SiOC with almost similar OER kinetics to RuO2. The bifunctional ability concluded that Ni/SiOC was a good bifunctional catalyst with an oxygen electrode potential 0.89 V. As Co/SiOC performs as a better ORR catalyst, it was utilized as a cathode catalyst for the construction of anion exchange membrane fuel cell and its fuel cell performance was evaluated. The Co/SiOC composites produce a peak power density of 54 mW/cm2, representing a satisfactory result when compared with Pt/C. The results reveal that the intermetallic nickel/cobalt silicide nanosphere decorated ceramic materials can have a promising future as efficient alternative electrocatalysts in electrochemical devices.
Model checking ontology‐driven reasoning agents using strategy and abstraction
Authors: Rakib Abdur , Faruqui Rokan Uddin 
Published: April 2019

SummaryWe present a framework for the modelling, specification, and verification of ontology‐driven multi‐agent rule‐based systems (MASs). We assume that each agent executes in a separate process and that they communicate via message passing. The proposed approach makes use of abstract specifications to model the behaviour of some of the agents in the system and exploits information about the reasoning strategy adopted by the agents. Abstract specifications are given as Linear Temporal Logic (LTL) formulas which describe the external behaviour of the agents, allowing their temporal behaviour to be compactly modelled. Both abstraction and strategy have been combined in an automated model checking encoding tool Tovrba for rule‐based multi‐agent systems which allows the system designer to specify information about agents' interaction, behaviour, and execution strategy at different levels of abstraction. The Tovrba tool generates an encoding of the system for the Maude LTL model checker, allowing properties of the system to be verified.
Diversity‐dependent plant–soil feedbacks underlie long‐term plant diversity effects on primary productivity
Authors: Guerrero‐Ramírez Nathaly R. , Reich Peter B. , Wagg Cameron , Ciobanu Marcel , Eisenhauer Nico 
Published: April 2019

AbstractAlthough diversity‐dependent plant–soil feedbacks (PSFs) may contribute significantly to plant diversity effects on ecosystem functioning, the influences of underlying abiotic and biotic mechanistic pathways have been little explored to date. Here, we assessed such pathways with a PSF experiment using soil conditioned for ≥12 yr from two grassland biodiversity experiments. Model plant communities differing in plant species and functional group richness (current plant diversity treatment) were grown in soils conditioned by plant communities with either low‐ or high‐diversity (soil history treatment). Our results indicate that plant diversity can modify plant productivity through both diversity‐mediated plant–plant and plant–soil interactions, with the main driver (current plant diversity or soil history) differing with experimental context. Structural equation modeling suggests that the underlying mechanisms of PSFs were explained to a significant extent by both abiotic and biotic pathways (specifically, soil nitrogen availability and soil nematode richness). Thus, effects of plant diversity loss on plant productivity may persist or even increase over time because of biotic and abiotic soil legacy effects.
Reproductive class influences risk tolerance during denning and spring for American black bears (Ursus americanus)
Authors: Gantchoff M. G. , Beyer D. , Belant J. L. 
Published: April 2019

AbstractDen sites are important for many species’ ecology, and individuals should choose den sites that minimize risk and maximize energy gain. We examined den site selection and spring space use for black bears (Ursus americanus) at the individual level, and analyzed support for the anthropogenic risk avoidance and infanticide avoidance hypotheses. We obtained telemetry data for 94 individual bears (71 F and 23 M) and collected 162 den locations from Michigan (2009–2011 and 2013–2015), Missouri (2010–2016), and Mississippi (2008–2017), USA. Of 71 females, 37 were monitored during multiple reproductive states. We used generalized linear mixed models to evaluate the influence of reproductive state (female with cubs, female with yearlings, female alone, or male) on den distance to the nearest road, two road indexes (den emergence and spring), spring home range size, mean spring road distance, and a NDVI selection index. All black bears, except females with cubs, chose den locations farther from roads than available to them, supporting the anthropogenic risk avoidance hypothesis. Additionally, females with cubs displayed the smallest spring home ranges among females, as well as denned closer to roads and used areas closer to roads during spring than females with yearlings, supporting the infanticide avoidance hypothesis. The differential responses by the same females when having cubs or yearlings point to strategies to maximize reproductive success. By investigating behavior considering individual availability, we revealed patterns that might not be detected by population‐level assessments.