bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereocontrolled Photoinduced Electron Transfer in Metal‐Fullerene Hybrids
Authors: Stasyuk Anton J. , Stasyuk Olga A. , Filippone Salvatore , Martin Nazario , Solà Miquel , Voityuk Alexander A. 
Published: June 2018

AbstractPhotoinduced electron transfer in transition‐metal complexes linked to a fullerene moiety is of increasing interest. Recently, several stereoisomers of an Ir‐complex exhibiting configurational stability at metal center, which does not undergo epimerization have been synthesized (Angew. Chem. Int. Ed. 2017, 56, 2136). The presence of multiple electron donor and acceptor sites located at opposite ends with respect to the metallic center creates the prerequisites for the formation of entirely different charge transfer (CT) states. Here we report the results of quantum mechanical calculations and detailed analysis of excited‐state properties for all stereoisomers of the junction. We found that the stereoisomers demonstrate clearly different CT properties by photoexcitation. The found photo‐stereospecific effects can be used to design new hybrids with a different type of photoinduced CT state, exhibiting dissimilar activity in photocatalysis.
Surrogate‐based visualization and sensitivity analysis of coronary stent performance: A study on the influence of geometric design
Authors: Ribeiro Nelson S. , Folgado João , Rodrigues Hélder C. 
Published: June 2018

AbstractThe main goal of this numerical study is to assess the impact of geometric design perturbations on the performance of a representative coronary stent platform. In this context, first, a design parameterization model was defined for the stent under study. After, a set of metrics characterizing stent performance, namely, vessel injury, radial recoil, bending resistance, longitudinal resistance, radial strength, the risk of fracture, prolapse index, and dogboning were evaluated within the context of a finite element analysis. Afterwards, accurate surrogate models were developed, using the efficient global optimization algorithm, as predictive tools in the execution of tasks that normally require a high number of model evaluations, such as global sensitivity analysis and visualization. In the end, the dependence of the output response surfaces on the geometric parameters was mechanically interpreted, which allowed us to understand the complex interplay that exists between the considered design variables and the defined performance metrics.
Enhanced Thermochemical Water Splitting through Formation of Oxygen Vacancy in La0.6Sr0.4BO3−δ (B=Cr, Mn, Fe, Co, and Ni) Perovskites
Authors: Wang Lulu , Al‐Mamun Mohammad , Zhong Yu Lin , Liu Porun , Wang Yun , Yang Hua Gui , Zhao Huijun 
Published: June 2018

AbstractOxygen vacancies in catalyst systems play a crucial role in manipulating pivotal redox properties that are strongly dependent on the composition of the material. Herein, for the first time, experimental evidence of a linear correlation between the extent of oxygen vacancy formation in the La0.6Sr0.4BO3 (B=Cr, Mn, Fe, Co, and Ni) perovskite series and H2 generation in two‐step thermochemical water splitting is reported, with detailed materials characterization by means of thermogravimetric analysis, XRD, SEM, TEM, and energy‐dispersive X‐ray spectroscopy. Noteworthy O2 (718 μmol g−1) and H2 (514 μmol g−1) production was achieved by the La0.6Sr0.4CoO3 perovskite in the thermochemical water‐splitting process conducted between 1300 and 900 °C.
Multi‐Step Continuous Flow Synthesis of β/γ‐Substituted Ketones
Authors: Garbarino Silvia , Protti Stefano , Gabrielli Serena , Fagnoni Maurizio , Palmieri Alessandro , Ravelli Davide 
Published: June 2018

AbstractThe smooth preparation of β/γ‐substituted ketones has been carried out by using a three‐step continuous flow synthesis involving the initial photocatalyzed addition of an aldehyde onto phenyl vinyl sulfone. The resulting β‐ketosulfones were then elaborated in flow to prepare in situ an enone upon basic elimination of the sulfonyl group and then to give γ‐nitroketones, a 4‐chromanone, and β‐(3‐indolyl)ketones in moderate to good yields.
Measuring performance degradation of virtual machines based on the Bayesian network with hidden variables
Authors: Hao Jia , Zhang Binbin , Yue Kun , Wu Hao , Zhang Jixian 
Published: June 2018

SummaryIn the virtualized environment, multiple virtual machines (VMs) sharing the same physical host are vulnerable to resource competition, which may cause performance interference among VMs and thus lead to VM performance degradation. This paper focuses on measuring CPU, memory, I/O, and the overall VM performance degradation caused by the performance interference according to the properties in the runtime environment of VMs. To this end, we adopt Bayesian network (BN), as the framework for uncertainty representation and inference, and construct a VM property‐performance BN (VPBN) with hidden variables, which represent the unobserved performance degradation of CPU, memory, and I/O, respectively. Then, we present the method to measure performance degradation of VMs by probabilistic inferences with the VPBN. Experimental results show the accuracy and efficiency of our method.
An efficient and secure 3‐factor user‐authentication protocol for multiserver environment
Authors: Luo Min , Sun Aiying , He Debiao , Li Xiaohong 
Published: June 2018

SummaryIn the last decade, the number of web‐based applications is increasing rapidly, which leads to high demand for user authentication protocol for multiserver environment. Many user‐authentication protocols have been proposed for different applications. Unfortunately, most of them either have some security weaknesses or suffer from unsatisfactory performance. Recently, Ali and Pal proposed a three‐factor user‐authentication protocol for multiserver environment. They claimed that their protocol can provide mutual authentication and is secure against many kinds of attacks. However, we find that Ali and Pal's protocol cannot provide user anonymity and is vulnerable to 4 kinds of attacks. To enhance security, we propose a new user‐authentication protocol for multiserver environment. Then, we provide a formal security analysis and a security discussion, which indicate our protocol is provably secure and can withstand various attacks. Besides, we present a performance analysis to show that our protocol is efficient and practical for real industrial environment.
Systematic investigations of novel validity parameters in urine drug testing and prevalence of urine adulteration in a two‐year cohort
Authors: Kluge Johanna , Rentzsch Linda , Remane Daniela , Peters Frank T. , Wissenbach Dirk K. 
Published: June 2018

AbstractUrinalysis is well established for drug screening. Various methods of urine adulteration such as dilution, addition of oxidative/reductive chemicals or detergents, and handing over urine‐like fluids are used to circumvent a positive screen. Validity parameters such as determination of pH, gravidity, urine temperature, or testing for oxidative/reductive chemicals are therefore used to uncover adulterated urine specimens. However, synthetic urine (“fake urine”) has nowadays been used for manipulations, leading to inconspicuous results with common validity test systems.Therefore, the aims of the study were (a) to evaluate additional validity parameters, (b) to evaluate the prevalence of urine adulteration, (c) to identify adulteration markers in purchased fake urine samples. Urine samples (n = 550) submitted for drug abstinence testing were analyzed by a standard urine liquid chromatography–tandem mass spectrometry (LC–MS/MS) screening approach using library‐assisted identification of 10 different endogenous biomolecules. The detection rates of biomolecules in authentic samples were phenylalanine (93.4%), tryptophan (97.1%), propionyl‐carnitine (67.1%), butyryl‐carnitine (99.6%), isovaleryl‐carnitine (92.8%), hexanoyl‐carnitine (91.0%), heptanoyl‐carnitine (97.1%), octanoyl‐carnitine (98.9%), and indoleacetylglutamine (98,2%). Phenylacetylglutamine was detected in each authentic sample. Based on the detection rates and measured creatinine levels, six manipulated samples were identified in this study. In two cases, fake urine was handed over, one time fake urine was most likely used for dilution. Once dilution with other fluids was used as adulteration method, while in another sample a detergent solution was handed over. Additionaly, one sample contained reactive chemicals. All fake urine samples were additionally identified by the detection of unique polyglycole patterns, which were observed in purchased fake urine samples.
Investigation of a New Anion Exchange Membrane‐based Direct Ammonia Fuel Cell System
Authors: Siddiqui O. , Dincer I. 
Published: June 2018

AbstractIn this study, a direct ammonia fuel cell comprising of an anion exchange membrane‐based electrolyte is developed, built and tested in the laboratory for investigating the performance electrochemically. In this regard, the aqueous ammonia is used as a storage medium for unreacted fuel. With gaseous ammonia fuel, an open circuit voltage (OCV) of 280 ± 8 mV is obtained at an operating temperature of 25 °C and a pressure of 100 kPa (1 bar). Furthermore, the peak power density at ambient conditions with gaseous ammonia fuel is observed to be 6.4 ± 0.3 W m−2. The unreacted gaseous fuel is stored in the form of aqueous ammonia and the fuel cell performance is tested at varying storage reservoir temperatures between 25 °C and 65 °C. An OCV of 110 ± 3 mV and a peak power density of 0.72 W m−2 is observed at an aqueous fuel temperature of 25 °C. Increasing storage reservoir and humidifier temperatures are found to improve the fuel cell performance characteristics.
Ein Beitrag zur Traglastermittlung mit der Kinematischen‐Elemente‐Methode (KEM) bei Dilatanz
Authors: Gußmann Peter 
Published: June 2018

AbstractNach einer auf das Nötigste reduzierten Einführung in die Methode der Kinematischen Elemente (KEM) und deren Einordnung in die Schrankentheoreme der Plastizitätstheorie wird im Hauptteil ein einfaches Erdwiderstandsproblem betrachtet. Die in anschaulichen und leicht nachvollziehbaren Grafiken dargestellten Ergebnisse beleuchten fast alle Aspekte der oft kontrovers diskutierten Problematik (mit und ohne Dilatanz) der Schrankenlösungen.
One MRI‐compatible tDCS session attenuates ventromedial cortical perfusion when exposed to verbal criticism: The role of perceived criticism
Authors: Baeken Chris , Dedoncker Josefien , Remue Jonathan , Wu Guo‐Rong , Vanderhasselt Marie‐Anne , De Witte Sara , Poppa Tasha , Hooley Jill M. , De Raedt Rudi 
Published: June 2018

AbstractTranscranial direct current stimulation (tDCS) is a potential treatment strategy for mood and anxiety disorders, but how this application may influence emotional processes, and whether this is related to individual characteristics, is not well understood. It has been proposed that perceived criticism (PC) may represent a vulnerability factor for the development of such mental illnesses. To decipher whether neural mechanisms of action of tDCS potentially differ depending on PC status (low vs. high), we evaluated mood and brain perfusion before and after applying MRI‐compatible tDCS, and after participants were exposed to verbal criticism in the scanner. Experimental design 30 healthy nondepressed females were included in a sham‐controlled crossover MRI‐compatible tDCS study. Brain perfusion was measured by means of arterial spin labeling (ASL) before and after tDCS applied to the left dorsolateral prefrontal cortex (DLPFC), and after hearing criticism. Before the experiment, all participants provided a rating of PC in their closest environment. Principal observations at the behavioral level, criticism made participants angrier. This was unrelated to the active or sham stimulation. After being criticized, females scoring high on PC had significantly decreased brain perfusion in the pregenual anterior cingulate cortex (pgACC) and medioprefrontal cortex (mPFC), after active tDCS but not sham. The decrease in pgACC/mPFC perfusion points to a significant impact of tDCS in brain areas related to stress responses and self‐referential processes, especially in females scoring high on PC, which has been shown to be related to vulnerability for mood and anxiety disorders.
Social health insurance vs private health insurance in China: Revisit crowd‐out effect based on a multiple mediation analysis
Authors: Zhang Ying , Su Anni , Liu Xiaoxing , Zhang Yue 
Published: June 2018

SummaryPlenty of scholars have studied social health insurance and private health insurance in different economies, and many concentrate on crowd‐out effect. Different results have been presented due to various data choices and empirical methodologies, but few of them have revealed the transaction mechanism. We study this issue based on updated Chinese provincial panel data from 2002 to 2014 and improved methods. We focus on how the crowd‐out effect happens through 3 channels—saving, demographic factor, and medical expenditure using multiple mediator models. Besides, we apply Panel VAR model to study magnitude of the impact these 3 channels contribute, corporately and respectively. Results clearly show that social health insurance has crowd‐out effect in penetration but crowd‐in effect in density caused by different mediation variables. In addition, the 3 channels have shown lasting and dynamic influences on the crowd‐out (in) effect. Finally, our paper provides the anti‐crowd‐out solutions from both perspectives according to our empirical analyses. For social health insurance system, it is necessary to improve the efficiency and fairness of the funds. For the private health insurance companies, insurance products innovation and privilege policy should be made to decrease the negative impact of saving and medical service overuse.
Development of pedotransfer functions for soil hydraulic properties in the critical zone on the Loess Plateau, China
Authors: Qiao Jiangbo , Zhu Yuanjun , Jia Xiaoxu , Huang Laiming , Shao Ming'an 
Published: June 2018

AbstractSoil hydraulic properties (SHPs) including the soil water retention curve and saturated soil hydraulic conductivity (Ks) are crucial input data for simulations of soil water and solute transport in the Earth's critical zone. However, obtaining direct measurements of SHPs at a wide range of scales is time consuming and expensive. Pedotransfer functions (PTFs) are employed as an alternative method for indirectly estimating these parameters based on readily measured soil properties. However, PTFs for SHPs for the deep soil layer in the Earth's critical zone are lacking. In this study, we developed new PTFs in the deep soil profile for Ks and soil water retention curve on the Loess Plateau, China, which were fitted with the van Genuchten equation. In total, 206 data sets comprising the hydraulic and basic soil properties were obtained from three typical sites. Samples were collected from the top of the soil profile to the bedrock by soil core drilling. PTFs were developed between the SHPs and basic soil properties using stepwise multiple linear regression. The PTFs obtained the best predictions for Ks (Radj2 = 0.561) and the worst for van Genuchten α (Radj2 = 0.474). The bulk density and sand content were important input variables for predicting Ks, α, and θs, and bulk density, clay content, and soil organic carbon were important for n. The PTFs developed in this study performed better than existing PTFs. This study contains the first set of PTFs of SHPs to be developed for the deep profile on the Loess Plateau, and they may be applicable to other regions.
Antimicrobial activity of amixicile against Treponema denticola and other oral spirochetes associated with periodontal disease
Authors: Reed Lucas A. , O'Bier Nathaniel S. , Oliver Lee D. , Hoffman Paul S. , Marconi Richard T. 
Published: June 2018

AbstractBackgroundPeriodontal disease is a polymicrobial infection characterized by inflammation of the gingiva, alveolar bone resorption and tooth loss. As periodontal disease progresses, oral treponemes (spirochetes) become dominant bacteria in periodontal pockets. Oral treponemes are anaerobes and all encode the enzyme pyruvate‐ferredoxin oxidoreductase (PFOR) which catalyzes the oxidative decarboxylation of pyruvate to acetyl‐CoA. Here we assess the susceptibility of oral treponemes to amixicile (AMIX), a novel inhibitor of PFOR.MethodsThe minimum inhibitory concentration (MIC) of AMIX against several oral treponeme species was determined. The impact of AMIX on processes relevant to virulence including motility, H2S production, and complement evasion were determined.ResultsThe growth of all oral treponeme species tested was inhibited by AMIX with MIC concentrations (MIC) ranging from 0.5–1.5 μg/mL. AMIX significantly reduced motility, caused a dose‐dependent decrease in hydrogen sulfide production and increased sensitivity to killing by human complement (i.e., serum sensitivity).ConclusionsAMIX is effective in vitro in inhibiting growth and other processes central to virulence. AMIX could serve could serve as a new selective therapeutic tool for the treatment of periodontal disease.
A silver self‐assembled monolayer‐decorated polydimethylsiloxane flexible substrate for in situ SERS detection of low‐abundance molecules
Authors: Zhao Hang , Hasi Wuliji , Bao Lin , Liu Yuping , Han Siqingaowa , Lin Dianyang 
Published: June 2018

AbstractThe preparation of highly sensitive and low cost substrate remains challenging in surface‐enhanced Raman spectroscopy (SERS). Here, a simple silver nanoparticle‐modified thin polydimethylsiloxane (PDMS) sheet was prepared as a SERS substrate via silicon‐assisted interfacial self‐assembly transfer and Langmuir–Schaefer deposition technique. The influence of the surface coverage on PDMS was investigated and optimized to achieve the maximal signal enhancement. Through the test of rhodamine 6G and 4‐mercaptobenzoic acid probe, the substrate showed good uniformity of nanoparticles, high‐enhanced factor, homogeneity of batch, time stability, and other properties. We, then, measured thiram and tricyclazole pesticides on the surface of apples, and the results demonstrate that SERS substrates can measure pesticide residues in situ.
Determination of inorganic cations in biological fluids using a hybrid capillary electrophoresis device coupled with contactless conductivity detection
Authors: Lobo‐Júnior Eulício Oliveira , L. S. Chagas Cyro , Coltro Wendell K. T. 
Published: June 2018

AbstractWe describe the assembly of a hybrid electrophoresis device that contains fused silica capillaries interconnected to a microfabricated interface in a cross format for the determination of inorganic cations in biological samples. The sample transport in the proposed hybrid device was performed under gated injection mode and the separations were monitored with a capacitively coupled contactless conductivity detector. The capillary extremities were inserted into polypropylene tubes to create solution reservoirs. Sensing electrodes were produced using stainless‐steel hypodermic needles previously cut with 2.0 mm length. The running composition and injection time were optimized and the best results were found using 50 mmol/L lactic acid, 20 mmol/L histidine and 3 mmol/L 18‐crown‐6 ether, and an electrokinetic injection time of 15 s. The separation of six inorganic cations was achieved with baseline resolution, and efficiencies were between 9.1 × 103 and 5.4 × 104 plates/m. The proposed hybrid device was explored for determining the concentration levels of inorganic cations in urine, saliva, and tear samples, employing Li+ as an internal standard. The achieved results were in good agreement with the data reported in the literature. The reliability of the proposed method ranged from 93 to 98%, thus suggesting satisfactory accuracy for bioanalytical applications.
Investigation of potential toxic components based on the identification of Genkwa Flos chemical constituents and their metabolites by high‐performance liquid chromatography coupled with a Q Exactive high‐resolution benchtop quadrupole Orbitrap mass spectrometer
Authors: Wang Zhipeng , Chu Yanjie , Zhang Yuanyuan , Chen Yu , Zhang Jingjing , Chen Xiaohui 
Published: June 2018

AbstractGenkwa Flos, a famous traditional Chinese medicine has been reported to have significant hepatotoxicity. A high‐throughput and reliable method was established to explore potential toxic components by high‐performance liquid chromatography coupled with a Q Exactive high‐performance benchtop quadrupole‐Orbitrap mass spectrometer. A total of 68 compounds including 22 chemical components and 46 metabolites were tentatively identified based on the accurately measured mass value, retention time, and fragmentation pattern. Besides, the metabolic pathways of main components in Genkwa Flos were also illustrated. The results indicated that hydroxylation, demethylation, methylation, glucuronidation, sulfation, cysteine conjugation, and glutathione conjugation participated in the metabolic reactions of Genkwa Flos. Moreover, 12 Genkwa Flos chemical components and 26 metabolites were detected in cell lysate, which were considered as the bound components to HL‐7702 cells. In view of cell affinity theory, these compounds were preliminarily deduced to be potential toxic ingredients for the hepatotoxicity induced by Genkwa Flos. The results demonstrated that the developed method was a very feasible and efficient approach for the components identification even in the complex matrix. In conclusion, this study will provide a deep insight into the toxic substances of Genkwa Flos and lay a chemical basis for in‐depth toxic studies on Genkwa Flos hepatotoxicity.
Trajectories of Psychological Distress in Australians Living in Urban Poverty: The Impact of Interpersonal Trauma
Authors: Keane Carol A. , Magee Christopher A. , Kelly Peter J. 
Published: June 2018

AbstractChildhood maltreatment and interpersonal trauma experience is an important factor underpinning the apparent perpetuation of the cycle of social disadvantage experienced by homeless adults. This paper aimed to examine longitudinal patterns of psychological distress in a sample of 1,504 socially disadvantaged adult participants from the Journeys Home Study in Australia. The current paper utilized the “conservation of resources” theory and the concept of “risk factor caravans” to investigate the nature and implications of childhood trauma in the context of homelessness. Growth mixture modeling revealed four distinct trajectories of psychological distress as measured by the Kessler 6 across six time points (covering a period of 2.5 years): chronic, escalating, attenuating, and resistant. Our results also indicated that experiences of different types of trauma during childhood were associated with these psychological distress trajectories. In particular, adults experiencing chronic psychological distress were significantly more likely than those exhibiting distress resistance to have experienced multiple and varied childhood maltreatment, adjusted odds ratio (AOR) = 3.30, 95% CI [0.37, 6.05], p = .002. Furthermore, adult experiences of assault were found to be associated with psychological distress. These findings have important implications for mental health, as well as interventions aimed at breaking the cycle of urban poverty. Specific focus on interpersonal trauma vulnerabilities is important. Prioritizing socioecological stability, with mental health needs assessed on an individual level, may be most appropriate. This work also highlights the need to direct future attention to barriers to access and facilitation of social support services.