bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of cascade reservoirs on the transformation of nitrogen in pore water of sediments in the Lancang River
Authors: Zhao Ping , Wang Congfeng , Wang Xue , Yang Zhengjian , Liu Defu 
Published: February 2021

AbstractIn the mainstream of the Lancang River, eight cascade dams have been constructed. In order to find the effects of the cascade reservoirs on the transformation of nitrate (NO3‐N) and ammonium (NH4‐N) in pore water of sediments, a field survey was carried out both in the upper natural river reach (NRR) and cascade reservoirs reach (CRR) of the Lancang River from January 10 to 20, 2018. The results indicated that (1) in the NRR, NO3‐N concentrations in sediment pore water were higher than those in the CRR, whereas the total nitrogen (TN) and NH4‐N were significantly lower; the diffusion fluxes of NH4‐N from sediment to overlying water varied from −0.180 to 0.049 mg·(m2·d)‐1, and the diffusion fluxes of NO3‐N varied from 0.012 to 0.098 mg·(m2·d)‐1. (2) in the CRR, the NH4‐N concentrations in sediment pore water were much higher than those in the overlying water, but the NO3‐N concentrations in the overlying water were much higher; the diffusion fluxes of NH4‐N from the sediments to the overlying water varied from 0.161 to 1.561 mg·(m2·d)‐1, but the NO3‐N diffused downward from the overlying water to the sediments and the diffusion fluxes varied from −0.011 to −0.223 mg·(m2·d)‐1. It was concluded that the cascade reservoirs could increase the NH4‐N concentration and inversely decrease the NO3‐N concentration in the sediment pore water, which meant that the risk of the nitrogen release from the sediment in the cascade reservoirs was much higher than that in the natural river.
Reading From Multiple Documents: The Role of Text Availability and Question Type
Authors: Cerdán Raquel , Máñez Ignacio , Serrano-Mendizábal Marian 
Published: February 2021

ABSTRACTThe current information society requires people to handle information from different sources, which entails specific skills beyond those needed to comprehend and use information from a single text. Given the relevance of becoming a competent reader in functional reading scenarios, it is crucial to examine how contextual‐, task‐, and individual‐related factors may influence multiple‐documents question‐answering activities, a key issue for assessment and instruction. In this study, we examined the influence of text availability and question type in students’ question‐answering performance and the moderator effect of students’ reading skill. Seventy secondary school students read three expository texts about a history topic. Next, they performed a concurrent question‐answering task consisting of a set of intra‐ and intertext questions they answered either with or without the texts available. Finally, participants performed a free‐recall task after a 24‐hour delay without access to the learning materials. Results showed higher performance scores in the intratext questions when the text was available than when it was not. However, the superiority of text availability disappeared in the delayed recall task. Additionally, skilled readers who had the texts available scored higher in the concurrent question‐answering task and, moreover, recalled more ideas in the recall task. These findings shed light on how contextual‐ (i.e., text availability), task‐ (i.e., question type), and student‐related (i.e., reading skill) factors may influence both adolescents’ question answering from multiple documents and their recall. The implications of these findings for the science of reading and the educational practice are discussed.
Effects of arbuscular mycorrhizal fungi symbiosis on microbial diversity and enzyme activities in the rhizosphere soil of Artemisia annua
Authors: Ma Junqing , Ma Yuan , Wei Zhuli , Wu Jiemin , Sun Chenyu , Yang Juan , Liu Lu , Liao Honglin , Chen Tingsu , Huang Jinghua 
Published: February 2021

AbstractWe explored the influence of symbiosis with arbuscular mycorrhizal fungi (AMF) on rhizosphere‐soil microecology and its relationship with the artemisinin content in Artemisia annua (Artemisia annua L.). Three treatment groups were established: A. annua in symbiosis with Funneliformis mosseae, A. annua in symbiosis with Glomus versiforme, and A. annua without AMF symbiosis as a blank control. The nutrient content, pH, microbial density, activity, diversity, and evenness as well as the urease, acid phosphatase, and sucrase activities of A. annua rhizosphere soil and the relative artemisinin content in A. annua in the absence and presence of AMF symbiosis were measured and analyzed at four stages: T1 (rosette stage, 30 d after transplanting), T2 (growth stage, 70 d after transplanting), T3 (mature stage, 90 d after transplanting), and T4 (harvest stage, 120 d after transplanting). The results showed that AMF symbiosis increased the activities of urease, acid phosphatase, and sucrase in the rhizosphere soil of A. annua; promoted the absorption and utilization of N and P; increased the relative content of artemisinin in the aboveground parts of A. annua; and improved the utilization of various carbon sources by rhizosphere microorganisms to some extent. In addition, AMF also improved the density, quantity. and diversity of microorganisms in the A. annua rhizosphere. Different AMF had different effects on A. annua. The results showed that AMF symbiosis improved the absorption and utilization of soil nutrients by A. annua and increased its relative artemisinin content. These results may provide a theoretical basis for the production of A. annua.
Neurotrophin-3 contributes to benefits of human embryonic stem cell-derived cardiovascular progenitor cells against reperfused myocardial infarction
Authors: Bi Wei , Wang Jinxi , Jiang Yun , Li Qiang , Wang Shihui , Liu Meilan , Liu Qiao , Li Fang , Paul Christian , Wang Yigang , Yang Huang-Tian 
Published: February 2021

Abstract
Acute myocardial infarction (MI) resulting from coronary ischemia is a major cause of disability and death worldwide. Transplantation of human embryonic stem cell (hESC)-derived cardiovascular progenitor cells (hCVPCs) promotes the healing of infarcted hearts by secreted factors. However, the hCVPC-secreted proteins contributing to cardiac repair remain largely unidentified. In this study, we investigated protective effects of neurotrophin (NT)-3 secreted from hCVPCs in hearts against myocardial ischemia/reperfusion (I/R) injury and explored the underlying mechanisms to determine the potential of using hCVPC products as a new therapeutic strategy. The implantation of hCVPCs into infarcted myocardium at the beginning of reperfusion following 1 hour of ischemia improved cardiac function and scar formation of mouse hearts. These beneficial effects were concomitant with reduced cardiomyocyte death and increased angiogenesis. Moreover, hCVPCs secreted a rich abundance of NT-3. The cardioreparative effect of hCVPCs in the I/R hearts was mimicked by human recombinant NT-3 (hNT-3) but canceled by NT-3 neutralizing antibody (NT-3-Ab). Furthermore, endogenous NT-3 was detected in mouse adult cardiomyocytes and its level was enhanced in I/R hearts. Adenovirus-mediated NT-3 knockdown exacerbated myocardial I/R injury. Mechanistically, hNT-3 and endogenous NT-3 inhibited I/R-induced cardiomyocyte apoptosis through activating the extracellular signal-regulated kinase (ERK) and reducing the Bim level, resulting in the cardioreparative effects of infarcted hearts together with their effects in the improvement of angiogenesis. These results demonstrate for the first time that NT-3 is a cardioprotective factor secreted by hCVPCs and exists in adult cardiomyocytes that reduces I/R-induced cardiomyocyte apoptosis via the ERK-Bim signaling pathway and promotes angiogenesis. As a cell product, NT-3 may represent as a noncell approach for the treatment of myocardial I/R injury.
Alternative education paths for pregnant girls and young mothers in Tanzania
Authors: Fute Antony Zakaria , Wan Xiulan 
Published: February 2021

AbstractThis paper aimed to elaborate the importance of investing in girls’ educating for socio‐economic development, by describing the Tanzania's Alternative Education Paths, following the ban of pregnant girls and young mothers in public regular schools. Qualitative design (document review) was used to collect and analyze data from different documents and official websites such as World Bank, UNESCO, UNICEF, and Ministries of Education. 3.6 million Primary and secondary aged children are out of school, and 5,500 girls drop out of school every year because of pregnancy in Tanzania. Open schools and Folk Development Colleges are not in good quality but opted as alternative paths for dropouts. Chinese adult education system and provision of sex education are few suggestions lamented in this article. Girls' education is essential and with the additional possible alternatives of ensuring pregnant girls’ right to education, the paper will help policymakers to think about the best option of ensuring pregnant girls’ and young mothers’ right to education.
Diastereoselective Synthesis of Some Spiroheterocycles Using Base Reusable Heterogeneous Achiral Nanocatalyst in Aqueous Media
Authors: Ghanbari Zahra , Naeimi Hossein 
Published: February 2021

AbstractThis research is based on the synthesis of some new diastereoselective spiroheterocycles relying on the application of nanocatalysts designed from the functionalized magnetic nanoparticles with tetrazole. Also, the achievement of suitable product with stereopurity through base catalytic path. Water as a green solvent, NiFe2O4 magnetic nanoparticles as a separable and reusable catalyst and using simple and high efficiency method are some important advantages of this research.
Synthesis, Crystal Structure, Optical Properties and Stability of New Bismuth‐Based Organic‐Inorganic Compounds (C6H9N2)aBibXc (X=Cl, Br, I)
Authors: Hu Xinru , Wang Jilin , Mao Wenhui , Zheng Guoyuan , Mo Shuyi , Tian Nan , Zhou Bing , Long Fei , Zou Zhengguang 
Published: February 2021

AbstractWe report a series of high‐quality, low‐dimension, and bismuth‐based organic‐inorganic hybrid single crystals (C6H9N2)aBibXc (X=Cl, Br, I) fabricated via a simple hydrothermal method. The crystal structure, intermolecular interactions, morphology, chemical groups, bond characterization, and optical and thermal stability of the samples were detailed via X‐ray single crystal diffractomete, Hirshfeld surface analysis, field scanning electron microscopy (FSEM), fourier transform infrared spectrometer (FTIR), Raman, thermal gravimetric (TG), and Ultraviolet‐visible (UV‐vis) diffuse reflectance spectra. The results indicated that the (C6H9N2)2BiCl5 and (C6H9N2)2BiBr5 crystals displayed a monoclinic system with a P21/n space group at room temperature; the (C6H9N2)BiI4 crystal was P21/c. Meanwhile, the band gap could be continuously adjusted between 3.2 eV and 1.6 eV via the nature of halide ligands. The samples also have good thermal stability. The starting decomposition temperature of (C6H9N2)2BiCl5, (C6H9N2)2BiBr5, and (C6H9N2)BiI4 were 200 °C, 250 °C, and 300 °C, respectively. Therefore, this kind of organic‐inorganic hybrid compounds will be assumed to be a promising candidate for optical and electronic applications.
Effect of Humidity on the Electrical Properties of Poly (3, 4‐Ethylenedioxythiophene) – Poly (Styrenesulfonate) and its Carbon Nanotube Composites
Authors: Nanda Omita , Gupta Nidhi , Biradar Ashok M. , Saxena Kanchan 
Published: February 2021

AbstractWe report the effect of humidity on the electrical properties of different conductivity grades (low and high) of the polymer poly (3, 4‐ethylenedioxythiophene)‐poly (styrenesulfonate) (PEDOT : PSS) and their nanocomposites comprising of single walled carbon nanotubes (SWCNT). Polymer nanocomposites were prepared by using PEDOT : PSS with different weight ratio of chemically treated single walled carbon nanotubes (CT‐SWCNT). Humidity dependent change in resistance of thin films of pure and nanocomposites was measured and analyzed in detail. This basic study on the various conductivity grade PEDOT : PSS polymers and their SWCNT nanocomposites elucidate their response to humidity. It was found that the resistance of low and high conductivity grade pristine PEDOT : PSS films show opposite trends with respect to humidity. Interestingly these trends reverse in their nanocomposites containing CT‐SWCNT. The present study might find useful information for researchers working in the area of polymer nanocomposite based devices and applications.
Sulphonamide‐Containing Oxazoline Hybrids as New Class of Neuroprotective Agents and Lead Molecule as Autophagy Inducer
Authors: Kadaiahgari Chandra Sekhar , Saha Moumita , Ravuri Srinath , Nandigama Sandeep , Saha Krishna Das , Banerji Biswadip 
Published: February 2021

AbstractSulphonamide derived oxazoline hybrid compounds showed neuroprotective effects by inducing autophagy. In the present study, a series of sulphonamide containing oxazoline hybrids were synthesized and their neuroprotective efficacy in neuronal cell lines was explored. All the compounds showed moderate to good neuroprotection against adrenal medulla cell lines (PC 12). Compound 6 j had good neuroprotective activity against PC 12 cell lines showing increased expression of autophagy regulatory proteins (ATG7, LC 3B, p62, Beclin‐1) and anti‐apoptotic proteins (Bcl‐2) and also decreased expression of pro‐apoptotic proteins (Bax and Bad). This study demonstrated clearly that compound 6 j showed neuroprotective effect through the induction of autophagy and opens up new avenues for a new class of compounds as neuroprotective therapeutic agents.
2‐(Quinol‐8‐yl)pyrrole‐Boron Difluoride Complexes, Simple and Tractable Structures Exhibiting Red Emission
Authors: Nakano Takeo , Sumida Akifumi , Naka Kensuke 
Published: February 2021

AbstractThe boron difluoride complex bearing 2‐(quinol‐8‐yl)pyrrole as a ligand was synthesized as well as its derivatives bearing aromatic ring substituents at the α‐position of the pyrrole moiety. These compounds showed the potentiality of good red emission character in spite of their simple structures. In the present paper, the details of their optical properties are described and discussed based on computational studies and X‐ray structural analysis.
Deep Denitrogenation of Model Diesel Fuel Using Ni‐doped Mesoporous Carbon: Synthesis Route and Adsorption Study
Authors: Delkhosh Arvin Saffarian , Vahid Amir , Baniyaghoob Sahar , Saber‐Tehrani Mohammad , Mohammdi Roozbeh Malek 
Published: February 2021

AbstractNickel‐doped mesoporous carbon (MC) materials with 1, 4, and 7 wt. % nickel/MC, were synthesized and utilized for the elimination of indole, as representative of nitrogen‐containing compounds, from a model diesel fuel. Different instrumental techniques, including Fourier‐transform infrared (FT‐IR) spectroscopy, X‐Ray diffraction (XRD), N2 adsorption‐desorption analyses, field emission scanning electron microscopy (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDXS), and transmission electron microscopy (TEM) were used to characterize the synthesized Ni‐doped mesoporous carbons. The XRD and N2 adsorption‐desorption results revealed that all the nickel‐modified materials had ordered hexagonal mesostructures. Response surface methodology coupled with a three‐variable, three‐level Box‐Behnken design (BBD) involving three center points and one response was employed for evaluating the influence of the three input parameters, namely temperature (A), contact time (B), and Ni content (C) on the adsorption yield. The optimum removal efficiency (96.5 %) was obtained at 42 °C, 1 wt. % of Ni loading, and 55 min contact time; also, possible adsorption mechanisms might be due to van der Waals interaction, H‐bonding, and π‐complexation. Additionally, the equilibrium data were analyzed using Langmuir, Freundlich, and Temkin isotherm models, and the Freundlich isotherm model showed a better fit to experimental data (R2 =0.9978).
Envisaging Future Energy Storage Materials for Supercapacitors: An Ensemble of Preliminary Attempts
Authors: Naskar Pappu , Chakraborty Priyanka , Kundu Debojyoti , Maiti Apurba , Biswas Biplab , Banerjee Anjan 
Published: February 2021

AbstractRecent developments in supercapacitor technology in terms of materials and devices are reviewed herein. Beyond the conventional materials (i. e., carbonaceous matters, metallic compounds and conducting polymers), various multifunctional materials are reported in literature as future supercapacitive materials. A comprehensive account on such materials is lacking due to the diversified electrochemical characteristics of these materials. In this review, we bring all such non‐conventional multifunctional energy storage materials under a same umbrella for summarizing the recent advancements in supercapacitors. The envisaged multifunctional materials include metal‐organic‐frameworks (MOFs), covalent‐organic‐frameworks (COFs), heteroatom‐doped carbonaceous materials, biomass‐derived porous carbons, black phosphorous, mixed conductors, perovskite nanoparticles, polyoxometalates (POMs), redox active electrolytes, slurry materials for flow supercapacitors, thermal self‐charging materials, thermal self‐protective materials, piezoelectric materials and electrochromic materials. Inherent pros and cons of each class of material are discussed, and materials modifications towards the successful device fabrications are highlighted herewith. While the MOF‐based supercapacitors are drawing some attentions, other non‐conventional energy storage materials are truly in the nascent stage of developments. This review culminates with summary and proposed future directions for product developments. In brief, this article provides a holistic view regarding all non‐conventional multifunctional energy storage materials for future supercapacitor technology.
Do R&D investments in weak IPR countries destroy market value? The role of internal linkages
Authors: Belderbos René , Park Jinhyuck (Joseph) , Carree Martin 
Published: February 2021

AbstractResearch SummaryThe growth of emerging economies has attracted R&D investments by multinational enterprises, but firms have struggled to protect their knowledge assets in these environments with weak intellectual property rights protection. Knowledge misappropriation may be reduced if firms use cross‐unit R&D teams to strengthen intra‐firm interdependencies and control. We examine the relationship between such internal linkage strategies, foreign R&D investments, and firm market valuation in a dynamic market valuation model for 117 leading multinational firms. While foreign R&D investments are positively associated with market value, IP risks in host countries reduce it. The latter effect disappears if firms have developed a pronounced internal linkage strategy in weak IP environments. Linkage strategy bears costs and, in the absence of IP risks, is negatively associated with market value.Managerial SummaryThe growing market potential of emerging economies has led to an increase in research & development (R&D) activities there by multinational firms. A known challenge to multinational R&D investors in these economies is the weak protection of intellectual property rights (IPR). Firms may seek to reduce the risks of local knowledge spillovers and IPR infringement by actively embedding internal linkages in the organization of R&D and relying on cross‐unit international R&D teams. We examine the consequences of such an internal linkage strategy for the performance effects of firms’ investments in weak IPR countries. Based on an analysis of 1763 cross‐border R&D investments by 117 leading multinational firms, we find that a firm's market value is negatively affected by new R&D investments in weak IPR countries, but that such a negative influence can indeed be mitigated if the firm's R&D organization embeds internal linkages. Consistent with this observation, we demonstrate that firms with an internal linkage strategy are able to limit local knowledge outflows in weak IPR environments. However, if an internal linkage strategy is applied in strong, rather than weak, IPR environments, it bears substantial costs and negatively affects performance.
Single‐Atom Catalysts Derived from Metal–Organic Frameworks for Electrochemical Applications
Authors: Zou Lianli , Wei Yong‐Sheng , Hou Chun‐Chao , Li Caixia , Xu Qiang 
Published: February 2021

AbstractSingle‐atom catalysts (SACs) have received tremendous attention due to their extraordinary catalytic performances. The synthesis of this kind of catalysts is highly desired and challenging. In the last few years, metal–organic frameworks (MOFs) have been demonstrated as a promising precursor for fabricating SACs. In this review, the progress and recent advances in the synthesis of MOF‐derived SACs and their electrochemical applications are summarized. First, the synthetic approaches based on MOFs and accessible characterization techniques for SACs as well as their advantages/disadvantages are discussed. Then, the electrochemical applications of these MOF‐derived SACs including the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), CO2 reduction reaction (CO2RR), nitrogen reduction reaction (NRR), and other energy‐related reactions are reviewed. Finally, insights into the current challenges and future prospects of this field are briefly presented.
Progress of Exsolved Metal Nanoparticles on Oxides as High Performance (Electro)Catalysts for the Conversion of Small Molecules
Authors: Sun Xiang , Chen Huijun , Yin Yimei , Curnan Matthew T. , Han Jeong Woo , Chen Yan , Ma Zifeng 
Published: February 2021

AbstractUtilizing electricity and heat from renewable energy to convert small molecules into value‐added chemicals through electro/thermal catalytic processes has enormous socioeconomic and environmental benefits. However, the lack of catalysts with high activity, good long‐term stability, and low cost strongly inhibits the practical implementation of these processes. Oxides with exsolved metal nanoparticles have recently been emerging as promising catalysts with outstanding activity and stability for the conversion of small molecules, which provides new possibilities for application of the processes. In this review, it starts with an introduction on the mechanism of exsolution, discussing representative exsolution materials, the impacts of intrinsic material properties and external environmental conditions on the exsolution behavior, and the driving forces for exsolution. The performances of exsolution materials in various reactions, such as alkane reforming reaction, carbon monoxide oxidation, carbon dioxide utilization, high temperature steam electrolysis, and low temperature electrocatalysis, are then summarized. Finally, the challenges and future perspectives for the development of exsolution materials as high‐performance catalysts are discussed.