bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterising the water use and hydraulic properties of riparian tree invasions: A case study of Populus canescens in South Africa
Authors: Ntshidi Z , Gush MB , Dzikiti S , Le Maitre DC 
Published: May 2018

Invasive alien plants (IAPs) pose a serious threat to the already limited water resources in dry countries like South Africa which are facing increasing water shortages. Much of South Africa is expected to get drier in future due to climate change. In addition, the future climatic conditions are also predicted to accelerate the rate at which IAPs will spread, due to favourable growing conditions, further disrupting the provision of goods and services. Previous studies on tree water use in South Africa focused on commercial forests of introduced genera mainly Pinus, Eucalyptus, and Acacia. This study sought to expand these observations by quantifying water use and its drivers in riparian Grey Poplar (Populus canescens) invasions in the Berg River catchment of South Africa. Whole tree hydraulic resistance ranged from ~ 1.4 MPa·h·g-1 for large trees to ~14.3 MPa·h·g-1 for the small ones. These resistances are higher than those found for poplars in temperate climates, suggesting substantial hydraulic constraints to transpiration. Daily peak transpiration varied from 5 to 6 L·tree-1 in small trees (~9.2 cm DBH) to between 35 and 40 L·tree-1 for large trees (~24 cm DBH). Stand-level transpiration peaked at ~4 mm·d-1 in summer (Jan–Feb). However, the annual total transpiration was only 338 mm due to the deciduous nature of the species and also the high hydraulic resistance in the transpiration stream. Daily transpiration was strongly correlated to solar radiation (R2 > 0.81) while the air vapour pressure deficit (VPD) constrained transpiration at high VPD values. We conclude that the water use of the poplar invasions is significantly lower than that of other riparian invasions. The impact of these invasions on the water resources is therefore likely quite low, warranting less priority in alien plant clearing operations aimed at salvaging water.
The Degree to Which Secondary School Teachers in Public Schools Accept the Use of Transformative Leadership by Their Principals from Their Perspective
Authors: Alhameedyeen Rahmeh Abbaas B. 
Published: May 2018

The study aimed at identifying the degree to which secondary school teachers in public schools accept the use of transformative leadership by their principals from their perspective. The study used the descriptive method, and developed a questionnaire containing (20) paragraphs. The validity and reliability of the study tool has been verified. The study population contains the working teachers of high schools of the first semester of the academic year 2017-2018. They were taken among secondary public schools at Zarqa Education Principalate II. A random sample of 250 teachers was taken. The study concluded the following results:- The mean averages and standard deviations showed that the degree to which secondary school teachers in public schools accept the use of transformative leadership by their principals from their perspective was moderate. Therefore, the study recommends that teachers be introduced to the importance of transformative leadership and give training courses to activate the application of transformative management in secondary public schools.- There are statistically significant differences in the grades of study's sample of the degree to which secondary school teachers in public schools accept the use of transformative leadership by their principals from their perspective due to gender variable that was in favor of males. Therefore, the study recommends holding training courses for secondary school teachers to apply in their schools.- There are statistically significant differences in the grades of study's sample of the degree to which secondary school teachers in public schools accept the use of transformative leadership by their principals from their perspective due to experience variable. Therefore, the study recommends that secondary school teachers in public schools should be informed of their experience from 1-10 years on this style of leadership.
Dinámica de cambio en las redes sociales y la formación de vínculos transnacionales: un caso de venezolanos profesionales viviendo en París
Authors: Allen González Ana Julia , Fazito Dimitri 
Published: May 2018

La teoría de redes sociales ha sido ampliamente documentada en el contexto de la migración internacional. La mayoría de estas investigaciones se han centrado en la fuerza que demuestran los vínculos de parentesco y amistad en la atracción de migrantes. Sin embargo, pocos estudios han indagado, empíricamente, los procesos de configuración de las redes y su influencia estructural sobre los procesos de movilidad territorial. El objetivo de este artículo es emplear la metodología de Análisis de Redes Sociales, para identificar propiedades estructurales que pueden estar influyendo sobre la difusión del fenómeno migratorio en Venezuela, describir la estructura reticular de la migración calificada y su evolución hacia la configuración de una posible comunidad transnacional. Para ello datos de redes personales fueron recolectados entre marzo y mayo de 2016, entre una comunidad de venezolanos profesionales residenciados en París. Los resultados confirman que las redes personales de los entrevistados poseen focos de radiación de comportamiento migratorio en Venezuela, y aunque las estructuras reticulares se muestran algo dispersas, también presentan ciertos rasgos de expansión que dejan en evidencia la configuración de una comunidad transnacional de venezolanos en París.
Thermo and pH Dual – Actuating Smart Porous Anodic Aluminum for Controllable Drug Release
Authors: Zhao Xiao‐Ping , Wang Shan‐Shan , Younis Muhammad Rizwan , Xia Xing‐Hua , Wang Chen 
Published: May 2018

AbstractA highly effective dual‐stimuli responsive porous anodic aluminum (PAA) nanomembrane is designed and fabricated for controllable and sustainable drug release. By a two‐step electrochemical anodization process, the nanochannel arrays in PAA membrane are divided into two separated parts. The first part is modified by copolymer‐liposome (colipid), which acts as the thermo and pH dual‐stimuli responsive capping material. The other part is used as the drug loading core. The liposome in capping layer has excellent biocompatibility, and the nanochannels array can provide a high drug loading capacity. Taking dexamethasone as the model drug, the experiment results show that the fabricated nanochannels can be well tuned to open or close state upon pH or temperature stimuli, which allows the controllable and sustainable drug release. The present work is of significant importance for constructing smart and intelligent drug carrier and release systems for clinical applications.
3D CNTs/Graphene‐S‐Al3Ni2 Cathodes for High‐Sulfur‐Loading and Long‐Life Lithium–Sulfur Batteries
Authors: Guo Zeqing , Nie Huagui , Yang Zhi , Hua Wuxing , Ruan Chunping , Chan Dan , Ge Mengzhan , Chen Xi'an , Huang Shaoming 
Published: May 2018

AbstractLithium–sulfur batteries suffer from poor cycling stability at high areal sulfur loadings (ASLs) mainly because of the infamous shuttle problem and the increasing diffusion distance for ions to diffuse along the vertical direction of the cathode plane. Here, a carbon nanotube (CNT)/graphene (Gra)‐S‐Al3Ni2 cathode with 3D network structure is designed and prepared. The 3D network configuration and the Al in the Al3Ni2 provide an efficient channel for fast electron and ion transfer in the three dimensions, especially along the vertical direction of the cathode. The introduction of Ni in the Al3Ni2 is able to suppress the shuttle effect via accelerating reaction kinetics of lithium polysulfide species conversion reactions. The CNT/Gra‐S‐Al3Ni2 cathode exhibits ultrahigh cycle‐ability at 1 C over 800 cycles, with a capacity degradation rate of 0.055% per cycle. Additionally, having high ASLs of 3.3 mg cm−2, the electrode delivers a high reversible areal capacity of 2.05 mA h cm−2 (622 mA h g−1) over 200 cycles at a higher current density of 2.76 mA cm−2 with high capacity retention of 85.9%. The outstanding discharge performance indicates that the design offers a promising avenue to develop long‐life cycle and high‐sulfur‐loading Li–S batteries.
Tailored Reaction Route by Micropore Confinement for Li–S Batteries Operating under Lean Electrolyte Conditions
Authors: Wang Hui , Adams Brian D. , Pan Huilin , Zhang Liang , Han Kee Sung , Estevez Luis , Lu Dongping , Jia Haiping , Feng Jun , Guo Jinghua , Zavadil Kevin R. , Shao Yuyan , Zhang Ji‐Guang 
Published: May 2018

AbstractLithium‐sulfur (Li–S) batteries are one of the most promising alternative energy storage systems beyond Li‐ion batteries. However, the sluggish kinetics of the nucleation and growth of the solid discharge product of Li2S/Li2S2 in the lower discharge plateau has been recently identified as a critical hurdle for attaining high specific capacity in Li–S batteries with high sulfur loadings under lean electrolyte conditions. Herein, a new strategy of breaking the charge‐transport bottleneck by successful generation of experimentally verified stable Li2S2 and a reservoir of quasi‐solid lithium polysulfides within the micropores of activated carbon fiber cloth as a high‐sulfur‐loading host is proposed. The developed Li–S cell is capable of delivering a highly sustainable areal capacity of 6.0 mAh cm−2 under lower electrolyte to sulfur ratios (<3.0 mLE gS−1). Micropore confinement leads to generation of solid Li2S2 that enables high utilization of the entire electroactive area by its inherent self‐healing capacity. This strategy opens a new avenue for rational material designs for Li–S batteries under lean electrolyte condition.
Click‐to‐Release from trans‐Cyclooctenes: Mechanistic Insights and Expansion of Scope from Established Carbamate to Remarkable Ether Cleavage
Authors: Versteegen Ron M. , ten Hoeve Wolter , Rossin Raffaella , de Geus Mark A. R. , Janssen Henk M. , Robillard Marc S. 
Published: May 2018

AbstractThe bioorthogonal cleavage of allylic carbamates from trans‐cyclooctene (TCO) upon reaction with tetrazine is widely used to release amines. We disclose herein that this reaction can also cleave TCO esters, carbonates, and surprisingly, ethers. Mechanistic studies demonstrated that the elimination is mainly governed by the formation of the rapidly eliminating 1,4‐dihydropyridazine tautomer, and less by the nature of the leaving group. In contrast to the widely used p‐aminobenzyloxy linker, which affords cleavage of aromatic but not of aliphatic ethers, the aromatic, benzylic, and aliphatic TCO ethers were cleaved as efficiently as the carbamate, carbonate, and esters. Bioorthogonal ether release was demonstrated by the rapid uncaging of TCO‐masked tyrosine in serum, followed by oxidation by tyrosinase. Finally, tyrosine uncaging was used to chemically control cell growth in tyrosine‐free medium.
Alternative Strategies with Iodine: Fast Access to Previously Inaccessible Iodine(III) Compounds
Authors: Hokamp Tobias , Mollari Leonardo , Wilkins Lewis C. , Melen Rebecca L. , Wirth Thomas 
Published: May 2018

AbstractNon‐iodinated arenes can be easily and selectively converted into (diacetoxyiodo)arenes in a single step under mild conditions by using iodine triacetates as reagents. The oxidative step is decoupled from the synthesis of hypervalent iodine(III) reagents, which can now be prepared conveniently in a one‐pot synthesis for subsequent reactions without prior purification. The chemistry of iodine triacetates was also expanded to heteroatom ligand exchanges to form novel inorganic hypervalent iodine compounds.
A novel polycarbonate composite for waveguides
Authors: Wu Xiaolan , Yang Bo , Zhuang Songlin 
Published: May 2018

ABSTRACTThe novel polycarbonate resin compositions comprising polycarbonate (PC) and acrylic resin were prepared by solution blending and analyzed by differential scanning calorimetry, atomic force microscopy, gel permeation chromatography, and gas chromatography‐mass spectrometry. Furthermore, the optical performance and the thermal and mechanical properties were tested, respectively. The results demonstrate that the blended material which was prepared by 100 parts of PC and 0.05 parts of acrylic resin achieves excellent transparency in blue‐light region (280–400 nm). Meanwhile, it retains excellent high‐heat resistance and mechanical performance of PC. Because of its high transparency in the blue‐light region which is caused by a doping of a tiny amount of acrylic resin, this material takes steps towards solving the optical problem that light becomes yellow when leaving the end of waveguides of PC. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46529.
Impact of the starch source on the physicochemical properties and biodegradability of different starch‐based films
Authors: Luchese Cláudia Leites , Benelli Patrícia , Spada Jordana Corralo , Tessaro Isabel Cristina 
Published: May 2018

ABSTRACTConcern about environmental issues has motivated research into the development of biodegradable packaging from renewable sources. Natural polymers such as starch constitute a good alternative for diminishing the use of nonbiodegradable and nonrenewable components in the packaging industry. However, depending on the botanical source, films with different properties are formed. The aim of this study was to evaluate the film‐forming capacity of different starch sources (cassava, corn, potato, and wheat) by casting with starch contents from 2 to 6%. Principal component analysis methodology was used to evaluate the correlation between the formulations and their physicochemical and mechanical properties. It was not possible to produce continuous films based on potato starch, probably because of its very low amylose content (10%). The corn‐, cassava‐, and wheat‐starch‐based films were characterized by their thicknesses (0.06–0.22 mm), moisture contents (19–26%), water solubilities (13.7–26.5%), water‐vapor permeabilities (WVPs; 0.19–0.48 g mm h−1 m−2 kPa−1), wettabilities (35–106°), biodegradabilities in soil, and thermal and mechanical properties (tensile strength = 1.9–6.7 MPa, elongation = 41–166%, and Young's modulus = 8–127 MPa). The wheat starch films presented higher WVPs and lower mechanical properties. The cassava starch films presented lower wettabilities and good mechanical properties; this suggested that their use in packaging for products, such as fruits and vegetables, with higher water activities could be feasible. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46564.
Cationic starch derivatives as reactive shale inhibitors for water‐based drilling fluids
Authors: Cescon Leonardo dos Santos , Quartarone Priscila , Ribeiro Simone Pereira da Silva , Nascimento Regina Sandra Veiga 
Published: May 2018

ABSTRACTOne of the major problems associated with the use of water‐based drilling fluids is the interaction of water with specific rock formations, such as shales, and the consequent swelling of reactive clays that may be present in that type of rock. Several types of clays reactivity inhibitors have been used by the oil industry, and the most effective ones are the cationic polyelectrolytes, such as the poly(diallyldimethylammonium chloride) (PDADMAC). However, this polyelectrolyte is very toxic. In this work, a series of cationic starch derivatives with different cationic degrees were synthesized with the objective of evaluating their potential as environmentally correct shale reactivity inhibitors. The results showed that the synthesized derivatives presented a good capacity of adsorption on bentonite and an efficient inhibition of the shale reactivity. The derivative with an intermediate cationic degree presented the best performance. In the tests with the formulated fluids this derivative provided an intact cuttings recovery of 84.8% and a total recovery of 92.3%. These values are very close to those found for the PDADMAC additive, therefore indicating that this cationic starch derivative presents a good potential as inhibitor of the shale reactivity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46621.
Trivalent rare‐earth activated hexagonal lanthanum fluoride (LaF3:RE3+, where RE = Tb, Sm, Dy and Tm) nanocrystals: Synthesis and optical properties
Authors: Kasturi Singh , Marikumar R. , Vaidyanathan Sivakumar 
Published: May 2018

AbstractThe LaF3 nanocrystals through a facile hydrothermal route with hexagonal structures have been synthesized via doping of trivalent rare earth (RE3+) ions – RE = Tb, Sm, Dy and Tm – with rod‐like and perforated morphologies using NH4F as fluorine precursor. Hexagonal phase formation was confirmed by powder X‐ray diffraction. The crystalline sizes were calculated by the Scherrer equation where found to have an average crystalline size of 12 to 35 nm. The morphological studies of the nanocrystals were carried out by means of transmission electron microscopy (TEM). The LaF3:Tm3+,Sm3+ ions show the characteristic emission of Tb3+ and Tm3+ respectively. In Sm3+‐doped LaF3, three prominent emission peaks at 561, 597 and 641 nm were found, which belong to 4G5/2 → 6H5/2, 4G5/2 → 6H7/2 (magnetic dipole) and 4G5/2 → 6H9/2 (electric dipole) transitions, respectively. The Dy3+ activated LaF3 shows blue and yellow emission and the corresponding CIE color coordinate show white light emission (CCT value 10650 K).
Effect of viscosity and dielectric constant variation on fractional fluorescence quenching analysis of coumarin dye in binary solvent mixtures
Authors: Bhavya P. , Melavanki Raveendra , Kusanur Raviraj , Sharma Kalpana , Muttannavar V. T. , Naik L. R. 
Published: May 2018

AbstractPhoto physical properties of fluorescent organic compounds give an immense improved knowledge on characteristics of excited state that is beneficial to devise innovate molecules and understand their performance in particular applications. Coumarin derivatives have been extensively investigated in this regard. This article narrates steady state fluorescence quenching measurements of a coumarin derivative namely 3‐hydroxy‐3‐[2‐oxo‐2‐(3‐oxo‐3H‐benzo[f]chromen‐2‐yl)‐ethyl]‐1,3‐dihydro‐indol‐2‐one (3HBCD) in a binary mixture of acetonitrile and 1,4‐dioxane. Aniline is used as quencher. Fluorescence intensity is large in acetonitrile and decreases as the percentage of 1,4‐dioxane in the solvent mixture increases. With modest quencher concentration a deviation towards the x axis is noticed in the Stern–Volmer (S–V) plots. This downward curvature is interpreted as due to the presence of 3HBCD in different conformers in the lowest energy level. Ground state intramolecular hydrogen bonding formation is observed due to the conformational changes in the solute. Figured estimations of various quenching parameters recommend that, while dynamic quenching prompts linearity in S–V plot at lower quencher concentration, increasing quenching efficiency with increasing medium viscosity suggests that reaction is not entirely controlled by material diffusion. Stern–Volmer constant increases with decreasing medium dielectric constant.
Nomograms incorporating genetic variants in BMP/Smad4/Hamp pathway to predict disease outcomes after definitive radiotherapy for non‐small cell lung cancer
Authors: Yang Ju , Xu Ting , Gomez Daniel R. , Yuan Xianglin , Nguyen Quynh‐Nhu , Jeter Melenda , Song Yipeng , Komaki Ritsuko , Hu Ye , Hahn Stephen M. , Liao Zhongxing 
Published: May 2018

AbstractHepcidin is crucial in regulating iron metabolism, and increased serum levels were strongly linked with poor outcomes in various malignancies. Thus, we investigated if genetic variants in the BMP/Smad4/Hamp hepcidin‐regulating pathway were associated with outcomes in patients receiving definitive radiotherapy for NSCLC. Subjects were 664 NSCLC patients who received ≥60 Gy radiotherapy for NSCLC retrospectively identified from a single‐institution database. Potentially, functional and tagging single nucleotide polymorphisms (SNPs) of BMP2 (rs170986, rs1979855, rs1980499, rs235768, and rs3178250), BMP4 (rs17563, rs4898820, and rs762642), Smad4 (rs12456284), and Hamp (rs1882694, rs10402233, rs10421768, and rs12971321) were genotyped by TaqMan real‐time polymerase chain reaction. Cox proportional hazard's analyses were used to assess potential influences of SNPs on overall survival (OS), local‐regional progression‐free survival (LRPFS), progression‐free survival (PFS), and distant metastasis‐free survival (DMFS). Nomogram of each endpoint model was developed using R project. The median patient age was 66 years. Most (488 [73.2%]) had stage III NSCLC. Age, disease stage, receipt of concurrent chemotherapy, and gross tumor volume were independent factors of OS. Hamp rs1882694 AC/CC genotypes were associated with poor OS, LRPFS, PFS, and DMFS in multivariate analyses. Besides, BMP2 rs1979855, rs3178250, and rs1980499 associated with PFS; Hamp rs10402233 and BMP2 rs1979855 associated with LRPFS; BMP2 rs3178250 associated with DMFS after adjustment for clinical factors. After adding SNPs to each model, all the likelihood ratios were increased; the nomograms were improved significantly to predict LRPFS (P < 0.001) and PFS (P < 0.001), and marginally to predict OS (P = 0.056) and DM (P = 0.057). Our nomograms incorporating significant SNPs in the BMP/Smad4/Hamp hepcidin‐regulating pathway could improve the prediction of outcomes in patients given definitive radiotherapy for NSCLC. Intensified follow‐ups would be recommended for patients with unfavorable outcomes identified in nomograms. Due to the rapid developments of targeted therapies and immunotherapies for NSCLC, it is necessary to further validate our findings in patients receiving such treatments.
Normal serum protein electrophoresis and mutated IGHV genes detect very slowly evolving chronic lymphocytic leukemia patients
Authors: Chauzeix Jasmine , Laforêt Marie‐Pierre , Deveza Mélanie , Crowther Liam , Marcellaud Elodie , Derouault Paco , Lia Anne‐Sophie , Boyer François , Bargues Nicolas , Olombel Guillaume , Jaccard Arnaud , Feuillard Jean , Gachard Nathalie , Rizzo David 
Published: May 2018

AbstractMore than 35 years after the Binet classification, there is still a need for simple prognostic markers in chronic lymphocytic leukemia (CLL). Here, we studied the treatment‐free survival (TFS) impact of normal serum protein electrophoresis (SPE) at diagnosis. One hundred twelve patients with CLL were analyzed. The main prognostic factors (Binet stage; lymphocytosis; IGHV mutation status; TP53, SF3B1, NOTCH1, and BIRC3 mutations; and cytogenetic abnormalities) were studied. The frequencies of IGHV mutation status, cytogenetic abnormalities, and TP53, SF3B1, NOTCH1, and BIRC3 mutations were not significantly different between normal and abnormal SPE. Normal SPE was associated with Binet stage A, nonprogressive disease for 6 months, lymphocytosis below 30 G/L, and the absence of the IGHV3‐21 gene rearrangement which is associated with poor prognosis. The TFS of patients with normal SPE was significantly longer than that of patients with abnormal SPE (log‐rank test: P = 0.0015, with 51% untreated patients at 5.6 years and a perfect plateau afterward vs. a median TFS at 2.64 years for abnormal SPE with no plateau). Multivariate analysis using two different Cox models and bootstrapping showed that normal SPE was an independent good prognostic marker for either Binet stage, lymphocytosis, or IGHV mutation status. TFS was further increased when both normal SPE and mutated IGHV were present (log‐rank test: P = 0.008, median not reached, plateau at 5.6 years and 66% untreated patients). A comparison with other prognostic markers suggested that normal SPE could reflect slowly advancing CLL disease. Altogether, our results show that a combination of normal SPE and mutated IGHV genes defines a subgroup of patients with CLL who evolve very slowly and who might never need treatment.