bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vapor phase fabrication of three‐dimensional arrayed BiI3 nanosheets for cost‐effective solar cells
Authors: Zhu Yiyi , Zhang Qianpeng , Kam Matthew , Poddar Swapnadeep , Gu Leilei , Liang Shijun , Qi Pengfei , Miao Feng , Fan Zhiyong 
Published: December 2019

AbstractMultilayered photovoltaic absorbers have triggered widespread attention for their unique structure and properties. However, multilayered materials in the randomly oriented polycrystalline thin‐film lead to ineffective carrier transport and collection, which hinders the process of achieving high‐performance solar cells. Herein, this issue is tackled by producing the three‐dimensional (3D) heterojunction BiI3 nanosheets (NSs) solar cells, which embed vertically aligned monocrystalline BiI3 NSs into spiro‐OMeTAD. The preferred orientation of BiI3 NSs and large p‐n junction areas of 3D heterojunction structure enable a strong light absorption and effective carrier transport and collection, and thus a power conversion efficiency (PCE) of 1.45% was achieved. Moreover, this PCE is the highest ever reported for BiI3 based solar cells to our best knowledge. Moreover, the nonencapsulated device remained 96% of the initial PCE after 24 h continuous one sun illumination at ~70% humidity condition, and 82% of the initial PCE after 1‐month storage at ~30% humidity condition.image
Forecasting stock returns with model uncertainty and parameter instability
Authors: Zhang Hongwei , He Qiang , Jacobsen Ben , Jiang Fuwei 
Published: December 2019

SummaryWe compare several representative sophisticated model averaging and variable selection techniques of forecasting stock returns. When estimated traditionally, our results confirm that the simple combination of individual predictors is superior. However, sophisticated models improve dramatically once we combine them with the historical average and take parameter instability into account. An equal weighted combination of the historical average with the standard multivariate predictive regression estimated using the average windows method, for example, achieves a statistically significant monthly out‐of‐sampleof 1.10% and annual utility gains of 2.34%. We obtain similar gains for predicting future macroeconomic conditions.
Determination of invert syrup adulterated in acacia honey by terahertz spectroscopy with different spectral features
Authors: Liu Wen , Zhang Yuying , Li Ming , Han Donghai , Liu Wenjie 
Published: December 2019

AbstractBACKGROUNDInvert syrup is a common adulterant in honey falsification, thus generating risk for consumers. Most of the methods developed are tedious and time‐consuming for manufactures and consumers. However, terahertz spectroscopy provides analytical information in a simple, rapid, and environmentally friendly manner. Subsequently, 3 kinds of terahertz spectroscopic characteristics data, the absorption coefficient, the slope of the absorption coefficient spectra, and the area of the absorption coefficient spectra, were employed for determination of acacia honey adulterated with invert syrup.RESULTSSingle linear regression (SLR) models with different terahertz spectroscopic features were adopted to predict the syrup adulterant proportion in acacia honey. The best SLR model used the area of the absorption coefficient, displaying an adjusted correlation coefficient of 0.985 and a root‐mean‐square error of 3.201. Meanwhile, multiple linear regression (MLR) models using a successive projections algorithm for variables selection were implemented. The MLR model considered the integral area of the absorption coefficient spectra, as the inputs yielded the best result with less variables selected, higher and , lower root‐mean‐square error of calibration and prediction, as well as higher residual predictive deviation.CONCLUSIONSThe results indicate terahertz spectroscopy combined with the integral area of the absorption coefficient spectra is reliable enough for invert syrup proportion quantification in acacia honey and is also a rapid and nondestructive determination method for other honey adulterants. © 2019 Society of Chemical Industry
Low‐Fouling Electrosprayed Hemoglobin Nanoparticles with Antioxidant Protection as Promising Oxygen Carriers
Authors: Liu Xiaoli , Jansman Michelle M. T. , Thulstrup Peter W. , Mendes Ana C. , Chronakis Ioannis S. , Hosta‐Rigau Leticia 
Published: December 2019

AbstractDespite all the attempts to create advanced hemoglobin (Hb)‐based oxygen carriers (HBOCs) employing an encapsulation platform, major challenges including attaining a high Hb loading and long circulation times still need to be overcome. Herein, the fabrication, for the first time, of nanoparticles fully made of Hb (Hb‐NPs) employing the electrospray technique is reported. The Hb‐NPs are then coated by antioxidant and self‐polymerized poly(dopamine) (PDA) to minimize the conversion of Hb into nonfunctional methemoglobin (metHb). The PDA shell is further functionalized with poly(ethylene glycol) (PEG) to achieve stealth properties. The results demonstrate that the as‐prepared Hb‐NPs are hemo‐ and biocompatible while offering antioxidant protection and decreasing the formation of metHb. Additionally, decoration with PEG results in decreased protein adsorption onto the Hb‐NPs surface, suggesting a prolonged retention time within the body. Finally, the Hb‐NPs also preserve the reversible oxygen‐binding and releasing properties of Hb. All in all, within this study, a novel HBOCs with high Hb content is fabricated and its potential as an artificial blood substitute is evaluated.
Effect of Two‐Step Chain Extension using Joncryl and PMDA on the Rheological Properties of Poly (lactic acid)
Authors: Yahyaee Nasrin , Javadi Azizeh , Garmabi Hamid , Khaki Amir 
Published: December 2019

AbstractThis research considers a two‐step chain extension reaction in the presence of two chain extenders, Joncryl and Pyromellitic dianhydride (PMDA), as a solution for poor melt properties of poly (lactic acid) (PLA). The aim of adding PMDA is to increase the carboxyl groups via the anhydride ring‐opening reaction so that the reaction between PLA and Joncryl could be facilitated since the reactivity between the epoxy and carboxyl group is more than epoxy and hydroxyl group. The reactions are confirmed by measuring the acid value, and a two‐step reaction mechanism is suggested. Shear and elongational rheological properties of the samples are investigated; furthermore, gel permeation chromatography analyses and tensile tests are exploited for studying the molecular weight and tensile properties, respectively. The results show that the chain extension reactions lead to an increase in the storage modulus, complex viscosity, and molecular weight. Also, the PLA chains which are extended utilizing both chain extenders simultaneously evince a synergistic improvement in the shear and elongational rheological properties due to longer segments between branching points on the structure.
An investigation on solidification path and hot tearing tendency of Mg−2Zn−3Y−xAl alloys
Authors: Zhang G. , Liu Z. , Wang Y. , Liu S. , Mao P. 
Published: December 2019

AbstractBased on the improved Clyne‐Davies’ model (CSCT), the hot tearing tendency of Mg−2Zn−3Y−xAl (x = 0, 0.5, 1, 2, wt.%) alloys were predicted. The concretion path, the solidification characteristic temperature, the dendrite coherent solid fraction were studied by the double thermocouples thermal analysis. The curve of solidification contraction stress with temperature (or time) was measured with a “T” type hot tearing permanent‐mold. The experimental results show that the modified Clyne‐Davies’ model prediction values are in good agreement with the experimental results. Al2Y phase can be used as the heterogeneous nucleation core of α‐Mg matrix and refine the α‐Mg grain size. It is found that Al2Y increases, grain refinement is more obvious, dendrite coherence is postponed, and the hot tearing susceptibility of the alloy decreases significantly with increasing aluminum content.
Effect of pin offset on the mechanical properties of friction stir welded AA 6013 aluminum alloy plates
Authors: Kasman Ş. , Ozan S. 
Published: December 2019

AbstractIn this study, AA 6013 aluminum plates were butt‐welded with friction stir welding via pin offset technique. Macrostructural observations revealed that kissing bonds, originated from the broken oxide layers, were found to occur in the welded joints. The fracture location of welded joints after tensile tests was found to be outside the joint area, revealing that kissing bonds which were formed in the stir zone exhibited no detrimental effect on the mechanical properties of joints. Microstructural observations revealed that phases belonging to Mg2Si, Al4Cu2Mg8Si7 and Al(MnFe)Si were observed in the x‐ray diffraction pattern of friction stir welded joints. The highest tensile strength with a value of 206 MPa was achieved with the process parameters of 1.5 mm pin offset towards the advancing side and 500 min−1 tool rotational speed, leading the ratio of tensile strength of joint to ultimate tensile strength of base metal, also known as joint efficiency, to reach 74 %.
Quantitative Evaluation of Iron Content in Idiopathic Rapid Eye Movement Sleep Behavior Disorder
Authors: Sun Junyan , Lai Zhaoyu , Ma Jinghong , Gao Linlin , Chen Meijie , Chen Jie , Fang Jiliang , Fan Yangyang , Bao Yan , Zhang Dongling , Chan Piu , Yang Qi , Ye Chenfei , Wu Tao , Ma Ting 
Published: December 2019

AbstractBackgroundIdiopathic rapid eye movement sleep behavior disorder is an early sign of neurodegenerative disease. This study aimed to quantitatively evaluate iron content in idiopathic rapid eye movement sleep behavior disorder patients using quantitative susceptibility mapping and to examine the potential of this technique to identify the prodromal stage of α‐synucleinopathies.MethodsTwenty‐five idiopathic rapid eye movement sleep behavior disorder patients, 32 Parkinson's disease patients, and 50 healthy controls underwent quantitative susceptibility mapping. The mean magnetic susceptibility values within the bilateral substantia nigra, globus pallidus, red nucleus, head of the caudate nucleus, and putamen were calculated and compared among groups. The relationships between the values and the clinical features of idiopathic rapid eye movement sleep behavior disorder and Parkinson's disease were measured using correlation analysis.ResultsIdiopathic rapid eye movement sleep behavior disorder patients had elevated iron in the bilateral substantia nigra compared with healthy controls. Parkinson's disease patients had increased iron in the bilateral substantia nigra, globus pallidus, and left red nucleus compared with healthy controls and had elevated iron levels in the bilateral substantia nigra compared with idiopathic rapid eye movement sleep behavior disorder patients. Mean magnetic susceptibility values were positively correlated with disease duration in the left substantia nigra in idiopathic rapid eye movement sleep behavior disorder patients.ConclusionsQuantitative susceptibility mapping can detect increased iron in the substantia nigra in idiopathic rapid eye movement sleep behavior disorder, which becomes more significant as the disorder progresses. This technique has the potential to be an early objective neuroimaging marker for detecting α‐synucleinopathies. © 2019 International Parkinson and Movement Disorder Society
Oxidized Pork Induces Oxidative Stress and Inflammation by Altering Gut Microbiota in Mice
Authors: Ge Yueting , Lin Shiman , Li Bowen , Yang Yuhui , Tang Xue , Shi Yonghui , Sun Jin , Le Guowei 
Published: December 2019

ScopeReduced digestibility of foods containing oxidized proteins and the subsequent excessive accumulation of undigested components in the colon may cause changes in the intestinal flora composition. This study evaluates the characteristics of this change and the potential adverse effects on organisms.Methods and resultsPork is cooked using sous‐vide or at high temperature and pressure (HTP), then freeze‐dried, resulting in different levels of oxidized damage. Mice are fed diets containing low‐ (LOP), medium‐ (MOP), or high‐oxidative damage pork (HOP) for 12 weeks. HOP intake increases mice body weight, induces inflammatory response, and causes oxidative stress, as indicated by the accumulation of oxidative products. Increased serum LPS levels and downregulation of tight junction‐related genes in the mucosa suggest mucosal barrier damage. Alterations in the cecal microbiota include reduced relative abundance of the mucin‐degrading bacteria Akkermansia, beneficial bacteria Lactobacillus and Bifidobacterium, and H2S‐producing bacteria Desulfovibrio and increased relative abundance of the pro‐inflammatory bacteria Escherichia‐Shigella and pathobiont Mucispirillum.ConclusionHOP intake causes the accumulation of oxidative products, increases body weight, damages the intestinal barrier, and induces oxidative stress and inflammatory response, likely by altering gut microbiota through protein oxidation (POX).
Mass Spectrometry Reveals New Insights into the Production of Superoxide Anions and 4‐Hydroxynonenal Adducted Proteins in Human Sperm
Authors: Netherton Jacob Kendal , Hetherington Louise , Ogle Rachel Anne , Gavgani Marum Mazloumi , Velkov Tony , Villaverde Ana Izabel Bilbin , Tanphaichitr Nuch , Baker Mark Andrew 
Published: December 2019

AbstractThe free‐radical theory of male infertility suggests that reactive oxygen species produced by the spermatozoa themselves are a leading cause of sperm dysfunction, including loss of sperm motility. However, the field is overshadowed on several fronts, primarily because: i) the probes used to measure reactive oxygen species (ROS) are imprecise; and ii) many reports suggesting that oxygen radicals are detrimental to sperm function add an exogenous source of ROS. Herein, a more reliable approach to measure superoxide anion production by human spermatozoa based on MS analysis is used. Furthermore, the formation of the lipid‐peroxidation product 4‐hydroxynonenal (4‐HNE) during in vitro incubation using proteomics is also investigated. The data demonstrate that neither superoxide anion nor other free radicals that cause 4‐HNE production are related to the loss of sperm motility during incubation. Interestingly, it appears that many of the 4‐HNE adducted proteins, found within spermatozoa, originate from the prostate. A quantitative SWATH analysis demonstrate that these proteins transiently bind to sperm and are then shed during in vitro incubation. These proteomics‐based findings propose a revised understanding of oxidative stress within the male reproductive tract.
CUSUM control charts with variable sampling interval for monitoring the ratio of two normal variables
Authors: Nguyen Huu Du , Tran Kim Phuc , Heuchenne Henri L. 
Published: December 2019

AbstractIn many industrial manufacturing processes, the ratio between two normal random variables plays a key role in ensuring quality of products. Thus, monitoring this ratio is an important task that is well worth considering. In this paper, we combine a variable sampling interval (VSI) strategy with a cumulative sum (CUSUM) scheme to create a new type of control chart for purpose of tracking the ratio between two normal variables. The average time to signal (ATS) and the expected average time to signal (EATS) criteria are used to evaluate the performance of the new VSI CUSUM RZ control chart. The numerical results show that the proposed control chart has much more attractive performance in comparison with the standard CUSUM‐RZ control chart and the VSI EWMA‐RZ control chart.
A theoretical study of the structural, thermoelectric, and spin‐orbit coupling influenced optoelectronic properties of CsTmCl3 halide perovskite
Authors: Ali Malak Azmat , Alam Neda ,   Meena, Ali Sonbal , Dar Sajad Ahmad , Khan Afzal , Murtaza G. , Laref A. 
Published: December 2019

AbstractThis first principles study explores the structural, electronic, optical, and thermoelectric properties of the CsTmCl3 halide perovskite using density functional theory. The structural and thermoelectric properties are calculated without considering the spin‐orbit coupling (SOC), while both the electronic and optical properties are calculated with and without the SOC effect. A comparison of the results obtained with and without SOC reveals that inclusion of the SOC effect reduces the band gap from 1.18 to 0.99 eV due to shifting of the Tm‐d states toward the Fermi level. However, direct nature of the band gap remains the same in both the cases. The effect of SOC on the optical properties is, however, only visible in shifting of the third characteristic peak to lower energies. Strong optical absorption in the visible and ultraviolet regions shows effectiveness of CsTmCl3 in the optical devices working in these regions. Moreover, the calculated transport properties reveal CsTmCl3 as a useful thermoelectric material at room temperature.
Uncertainty contribution of derivatization in gas chromatography/mass spectrometric analysis
Authors: Vilbaste Martin , Tammekivi Eliise , Leito Ivo 
Published: December 2019

RationaleThe purpose of the current work is to realistically assess the uncertainty contribution in gas chromatography/mass spectrometry (GC/MS) analysis originating from less‐than‐ideal derivatization efficiency.MethodsAs the exemplary analytical method a two‐step derivatization method with KOH and BSTFA (N,O‐bis(trimethylsilyl)trifluoroacetamide), applied for the analysis of fatty acid triglycerides (using real measurement data), was selected. The derivatization efficiencies were in the range 0.89–1.04. In this study, two approaches for bottom‐up uncertainty evaluation were compared: the traditional GUM approach and the Monte Carlo method (MCM). Both were used with and without taking correlation between input quantities into account.ResultsThe most reliable uncertainty estimates were in the range 0.07–0.08 (expanded uncertainties at 95% coverage probability). A strong negative correlation was found between the slope and intercept of the calibration graph (r = −0.71) and it markedly influenced the uncertainty estimate of derivatization efficiency. The MCM was found to give somewhat higher uncertainty estimates, which are considered more realistic.ConclusionsDerivatization directly affects the analysis result. Thus, in the case of this exemplary analysis, just derivatization alone (i.e. if all other uncertainty sources are neglected) causes relative expanded uncertainty around 8%, being thus an important and in some cases the dominant uncertainty contributor.
Cas12a mediates efficient and precise endogenous gene tagging via MITI: microhomology-dependent targeted integrations
Authors: Li Pan , Zhang Lijun , Li Zhifang , Xu Chunlong , Du Xuguang , Wu Sen 
Published: December 2019

AbstractEfficient exogenous DNA integration can be mediated by Cas9 through the non-homology end-joining pathway. However, such integrations are often imprecise and contain a variety of mutations at the junctions between the external DNA and the genomic loci. Here we describe a microhomology-dependent targeted integration method, designated MITI, for precise site-specific gene insertions. We found that the MITI strategy yielded higher knock-in accuracy than Cas9 HITI for the insertion of external DNA and tagging endogenous genes. Furthermore, in combination with negative selection and four different CrRNAs targeting donor vectors and genome-targeted sites with a CrRNA array, MITI facilitated precise ligation at all junctions. Therefore, our Cas12a-based MITI method increases the repertoire of precision genome engineering approaches and provides a useful tool for various gene editing applications.
Effect of positive/negative electrode ratio on cold metal transfer welding of 6061 aluminum alloy
Authors: Zhang Peilei , Li Guojin , Yan Hua , Tian Yingtao 
Published: December 2019

AbstractVariable polarity cold metal transfer (VPCMT) is a newly developed welding process and has drawn extensive interests because of its potential in further reducing the heat input, offering greater gap bridging ability, and improving the deposition rate. Using 6061 aluminum alloy as an example, this paper systematically investigated the influences of the key parameter in VPCMT, i.e., “positive/negative electrodes ratio (EP/EN Balance),” on weld formation, microstructure, and mechanical properties. It was found that, with the increase of the EP/EN Balance value, the duty cycle of the negative phase was reduced but the peak current and maximum temperature of the weld pool were both increased resulting in a higher heat input. The positive/negative electrode ratio had little impact on the grain misorientation angle in the fusion zone. Hardness of the joint was higher with larger positive duty cycles because of the precipitate phase and small grain size. An increased negative duty cycle resulted in lower heat input leading to insufficient melting of the material and deterioration of the mechanical strength of the welds.
Existence of Meromorphic Solutions of First-Order Difference Equations
Authors: Korhonen Risto , Zhang Yueyang 
Published: December 2019

AbstractIt is shown that if $$\begin{aligned} f(z+1)^n=R(z,f), \end{aligned}$$f(z+1)n=R(z,f),where R(z, f) is rational in f with meromorphic coefficients and $$\deg _f(R(z,f))=n$$degf(R(z,f))=n, has an admissible meromorphic solution, then either f satisfies a difference linear or Riccati equation with meromorphic coefficients, or the equation above can be transformed into one in a list of ten equations with certain meromorphic or algebroid coefficients. In particular, if $$f(z+1)^n=R(z,f)$$f(z+1)n=R(z,f), where the assumption $$\deg _f(R(z,f))=n$$degf(R(z,f))=n has been discarded, has rational coefficients and a transcendental meromorphic solution f of hyper-order $$<1$$<1, then either f satisfies a difference linear or Riccati equation with rational coefficients, or the equation above can be transformed into one in a list of five equations which consists of four difference Fermat equations and one equation which is a special case of the symmetric QRT map. Solutions to all of these equations are presented in terms of Weierstrass or Jacobi elliptic functions, or in terms of meromorphic functions that are solutions to a difference Riccati equation. This provides a natural difference analogue of Steinmetz’ generalization of Malmquist’s theorem.