bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epoxy resin with excellent ultraviolet resistance and mechanical properties derived from renewable camphoric acid
Authors: Hu Jingyuan , Wang Chunhong , Dai Jinyue , Teng Na , Wang Shuaipeng , Zhang Liyue , Jiang Yaming , Liu Xiaoqing 
Published: May 2021

AbstractGenerally, high‐performance epoxy resins, which are derived from aromatic compounds have two major disadvantages of yellowing and brittleness, and thus it presently remains a challenge for the facile synthesis of epoxy resin with excellent ultraviolet resistance and superior strength and toughness. Herein, a novel bio‐based epoxy resin diglycidyl ester of camphoric acid (DGECA) was synthesized from the renewable camphoric acid via an efficient and scalable route. The chemical structure of DGECA was carefully characterized by Fourier transform infrared (FT‐IR), nuclear magnetic resonance (NMR), and mass spectrometry before being cured with methylhexahydrophthalic anhydride (MHHPA). Compared with the cured diglycidyl ether of bisphenol A (DGEBA)/MHHPA, the cured DGECA/MHHPA system achieved 11.5%, 16.7%, and 109.4% increment in flexural strength (126 MPa vs. 113 MPa), modulus (2.8 GPa vs. 2.4 GPa), and impact strength (6.7 kJ/m2vs. 3.2 kJ/m2), respectively. Moreover, cured DGECA exhibited extremely lower ultraviolet absorption (0.038A) and better ultraviolet resistance than that of cured DGEBA. This work provides a new strategy to synthesize epoxy resin with excellent ultraviolet resistance and high toughness by using the unique structure of renewable feedstock.
Elucidating the biochemical basis of trans‐16:1 fatty acid change in leaves during cold acclimation in wheat
Authors: Li Qiang , Shen Wenyun , Mavraganis Ioannis , Wang Liping , Gao Peng , Gao Jie , Cram Dustin , Li Yifeng , Liu Ziying , Fowler David Brian , Pan Youlian , Zou Jitao 
Published: May 2021

AbstractIn plant cells, phosphatidylglycerol (PG) in the chloroplast has a characteristic trans‐∆3‐hexadecenoic acid (t16:1) at the sn‐2 position. The t16:1 content in wheat leaf tissues decreases during cold treatment, but the significance of this fatty acid compositional change and the underlying biochemical mechanism remains poorly understood. Using a large collection of wheat cultivars displaying a varying capacity of freezing tolerance, we show for the first time under field conditions that this low temperature induced t16:1 change is associated with winter hardiness. To explore the metabolic mechanism responsible for the reduction of t16:1, we performed detailed lipid analysis and comparative transcriptome study with four selected wheat lines under cold acclimation. Our results show that wheat leaf tissues experience a gradual decrease in chloroplast lipid pathway activity during cold acclimation and that the decline in chloroplast lipid synthesis manifests itself in the decrease of t16:1 in PG. Comparative RNA‐seq analyses with leaf tissues further reveal concerted transcriptome shifts indicating a rebalancing of chloroplast and cytosolic lipid synthesis during cold acclimation. Our study, thus, provides mechanistic understanding on chloroplast lipid adjustments as a “molecular ideotype” and the t16:1 change as a specific metabolite marker for screening freezing tolerance in wheat.
Silicon solar cells and modules with front contact paste containing copper‐based component
Authors: Gawlinska‐Necek Katarzyna , Socha Robert P. , Balawender Pawel , Stodolny Maciej K. , Van Aken Bas B. , Starowicz Zbigniew , Panek Piotr 
Published: May 2021

AbstractIn this article, we present the results of aging tests of silicon photovoltaic modules with a copper‐containing electrode deposited in one‐step screen printing method. For front metallization, a mixture of commercial silver paste with copper filler was used, where copper constituted 30% of total paste volume. The filler is based on copper particles about 1 μm of diameter covered with a protective coating layer based on nickel (CCu1) or nickel–silver (CCu2). For the first time, Si solar cells with screen‐printed front electrode containing massive copper with efficiency over 20% are reported. Aging tests included 2000 h of damp heat (DH) and 400 times of thermal cycling (TC) tests. TC results are very promising and provide slight deterioration of the electrical parameters of the modules with both CCu1 and CCu2. Greater decreases were found when performed DH tests, but it is worth pointing out that mainly fill factor (FF) and η have fallen while Voc and Isc did not change by more than 5% for both pastes. After 2000 h of the test, FF decreased by 28% for CCu1 and 37.4% for CCu2, whereas the efficiency deteriorated by 32% and 42.6% for CCu1 and CCu2. The electroluminescence (EL) and X‐ray photoelectron spectroscopy (XPS) measurements suggest that decrease in electrical parameters is a consequence of Cu corrosion caused by harmful products of the decomposed EVA laminating film.
The role of psychological and academic variables in predicting transition from primary to secondary education exam achievement in Turkey
Authors: Ersöz Çakir Olcay , Işmen Gazioğlu Ayşe Esra 
Published: May 2021

AbstractThe purpose of this study was to understand the role of academic (achievement goal orientation, academic self‐efficacy) and psychological (resilience, test anxiety) variables in predicting transition from primary to secondary education (TEOG) test achievement. Participants were eighth grade students (N = 334) in Istanbul. The data was gathered via 2 × 2 achievement goal questionnaire‐revised, academic self‐efficacy scale, resilience scale for early adolescents, state‐trait anxiety inventory and information form. Results showed that the mastery‐approach, performance‐approach, performance‐avoidance, academic self‐efficacy, psychological resilience, and trait anxiety were significant predictors of TEOG scores of the students. This study showed that the success of the national‐level transition to high school exam in Turkey was strongly associated with academic variables, and also weakly associated with psychological variables.
Is social function a good proxy measure of personality disorder?
Authors: Tyrer Peter , Yang Min , Tyrer Helen , Crawford Mike 
Published: May 2021

AbstractBackgroundPersonality assessment may be helped by proxy measures.AimsTo examine the assessment of social functioning in relationship to personality disorder.MethodSecondary analysis of data from three clinical studies, following deliberate self‐harm (n = 460), cognitive behaviour therapy for health anxiety (n = 444) and a 30‐year follow‐up of 200 anxious/depressed patients. Social function and personality were assessed using the Social Functioning Questionnaire (SFQ) and the Personality Assessment Schedule, with its ICD‐11 modification. A 5‐item short version of the SFQ, the Short Social Functioning Questionnaire (SSFQ), was also developed.The SFQ score in the first two studies (area under curve [AUC] 0.64 and 0.65) partly predicted personality status; in the third study, this achieved close agreement (AUC SFQ 0.85 [95% CI 0.8–0.9]; AUC SSFQ 0.84 [95% CI 0.78–0.89]). In all studies, social function deteriorated linearly with increasing personality pathology. Cut‐off points of 4 on the SSFQ and 7 on the SFQ had high sensitivity (SSFQ 82%–90%; SFQ 82%–83%) and acceptable specificity (SSFQ 66%–75%; SFQ 69%–75%) in identifying personality disorder in the third study.ConclusionsSocial functioning recorded in either a 5‐item or 8‐item self‐rating is a useful proxy measure of personality disturbance and may be the core of disorder.
Synthesis of 3D Porous Network Nanostructure of Nitrated Bacterial Cellulose Gel with Eminent Heat‐Release, Thermal Decomposition Behaviour and Mechanism
Authors: Chen Ling , Cao Xinfu , Gao Jianbing , Wang Yingbo , Zhang Yang , Liu Jie , He Weidong 
Published: May 2021

AbstractIn this study, a novel three‐dimensional (3D) porous cross‐link network structure of nitrated bacterial cellulose (NBC) nano‐gel, as an energetic gel matrix for fabrication of nanocomposite energetic materials, (nEMs) was synthesized by sol‐gel synthetic and the freeze‐drying technology. The analysis results revealed that the unique network structure with abundant of nano‐porous, which made the thermal behaviour of the NBC gel different from that of raw NBC. The thermal decomposition kinetic and mechanism of the NBC gel indicated that the exothermic peak temperature of the gel matrix decreased at low concentration, and the activation energy (Ea) of the gel0.5 (150000 J ⋅ mol−1) was much lower than that of raw NBC (223510 J ⋅ mol−1). However, the decomposition kinetic parameters of this study were not enough to illustrate the thermal properties, and which needs more effort to study them and complete. Furthermore, the initial reaction of gel decomposition was the splitting of urethane bond, and then the scission of −O−NO2 bonds happened, and the macromolecular chains’ breakage site of gel first occurred at −C−O−C− in the ring. After then, the chains of NBC break at −C−O−C− between the rings; notably, the heat‐release of gel was several times than that of raw NBC, which was liberated during the process of thermal decomposition. This promising research may provide potential application in preparing binder‐based nEMs and the basic theory of thermo‐analysis used in propellants and explosives.
Conformation of myelin basic protein bound to phosphatidylinositol membrane characterized by vacuum‐ultraviolet circular‐dichroism spectroscopy and molecular‐dynamics simulations
Authors: Kumashiro Munehiro , Izumi Yudai , Matsuo Koichi 
Published: May 2021

AbstractThe 18.5‐kDa isoform of myelin basic protein (MBP) interacts with the membrane surface of the myelin sheath to construct its compact multilamellar structure. This study characterized the conformation of MBP in the membrane by measuring the vacuum‐ultraviolet circular‐dichroism (VUVCD) spectra of MBP in the bilayer liposome comprising the following essential lipid constituents of the myelin sheath: phosphatidylinositol (PI), phosphatidylinositol‐4‐phosphate (PIP), and phosphatidylinositol‐4,5‐bisphosphate (PIP2). The spectra of MBP exhibited the characteristic peaks of the helix structure in the presence of PI liposome, and the intensity increased markedly in the presence of PIP and PIP2 liposomes to show an isodichroic point. This suggests that the amount of the membrane‐bound conformation of MBP enhanced due to the increased number of negative net charges on the liposome surfaces. Secondary‐structure analysis revealed that MBP in the membrane comprised approximately 40% helix contents and eight helix segments. Molecular‐dynamics (MD) simulations of the eight segments were conducted for 250 ns in the presence of PI membrane, which predicted two amphiphilic and three nonamphiphilic helices as the membrane‐interaction sites. Further analysis of the distances of the amino‐acid residues in each segment from the phosphate group suggested that the nonamphiphilic helices interact with the membrane surface electrostatically, while the amphiphilic ones invade the inside of the membrane to produce electrostatic and hydrophobic interactions. These results show that MBP can interact with the PI membrane via amphiphilic and nonamphiphilic helices under the control of a delicate balance between electrostatic and hydrophobic interactions.
Opening Texts for Discussion: Developing Dialogic Reading Stances
Authors: Barak Matan , Lefstein Adam 
Published: May 2021

ABSTRACTDialogic pedagogy, in which students and teachers voice thoughts, co‐construct meanings, and generate multiple interpretations of texts, can promote literacy skills and reasoning. Yet, such teaching is challenging and requires, among other changes, adopting dialogic stances. In the language arts, expressive and critical reading stances have been shown to encourage and support dialogic discussions. How can teachers develop such dialogic reading stances? In this study, we investigated the processes through which teachers negotiated reading stances in a professional development program. Specifically, we studied teachers’ participation in rereading discussions designed to open texts to multiple interpretations as preparation for leading productive dialogue in language arts lessons. We used systematic observation and microethnographic methods to analyze nine rereading discussions among 17 teachers, coaches, and researchers. Five reading stances emerged in the discussions: expressive, critical, instrumental, moralistic, and historical. Focusing on three case studies, we investigated the interactional conditions under which dialogic stances did and did not emerge and the opportunities and limitations of different reading stances for opening texts to dialogue. Our analysis shows that dialogic stances gained legitimacy during discussions in which leadership and facilitation supported gradual elaborations of the text. In contrast to our initial assumptions, we found that expressive and critical stances sometimes narrow interpretive possibilities, whereas instrumental and moralistic stances can be generative of dialogue during rereading discussions. We show the potential of cultivating dialogic stances for the promotion of dialogic pedagogy in the language arts and discuss the advantages and limitations of rereading discussions as professional development.
A Novel Calix[4]arene Thiourea Decorated with 2‐(2‐Aminophenyl)benzothiazole Moiety as Highly Selective Chemical Gas Sensor for Dichloromethane Vapor
Authors: Durmaz Mustafa , Acikbas Yaser , Bozkurt Selahattin , Capan Rifat , Erdogan Matem , Ozkaya Cansu 
Published: May 2021

AbstractA newly synthesized calix[4]arene thiourea derivative decorated with 2‐(2‐aminophenyl)benzothiazole unit is selected to take part important role in host‐guest interactions of the macrocyclic molecules. p‐tert‐butylcalix[4]arene dithiourea (C[4]‐DT) Langmuir‐Blodgett (LB) thin films are prepared and characterized to develop a new sensing element for the detection of seven different organic vapors (dichloromethane, chloroform, acetone, benzene, carbon tetrachloride, toluene and m‐xylene). The preparation of C[4]‐DT‐based thin films onto the different substrates was successfully and uniformly achieved with linear regressions of 0.9971 and 0.9954 for coating onto quartz glass and quartz crystal, respectively. The frequency shift (61.01 Hz) and the mass deposited onto quartz crystal (969.80 ng) were calculated for each layer. The swelling dynamics of C[4]‐DT QCM chemical sensor was also illuminated by developing the early time Fick's diffusion equation. The sensing measurements can be concluded that owing to its high sensitivity (6.63 Hz/ppm), fast response and low detection limit (0.45 ppm), this proposed C[4]‐DT LB coated sensor is expected to be promising alternative chemical sensor for detection of DCM vapor.
Synthesis, Spectral Characterization and Crystal Structures of Five Organic Ammonium Tetrasulfidomolybdates
Authors: Srinivasan Bikshandarkoil R. , Dhuri Sunder N. , Naik Ashish R. , Näther Christian , Bensch Wolfgang 
Published: May 2021

AbstractThe syntheses, spectral characterization and crystal structures of five organic ammonium tetrasulfidomolybdates namely (C4H12N)2[MoS4] 1 (C4H12N is 2‐methyl‐propan‐2‐aminium), (C5H16N2)[MoS4] 2 (C5H16N2 is N1,N1‐dimethylpropane‐1,3‐diaminium) (C5H16N2)[MoS4] 3 (C5H16N2 is N1,N3‐dimethylpropane‐1,3‐diaminium) (C6H20N4)[MoS4] 4 (C6H20N4 is 2‐amino‐N‐{2‐[(2‐ammonioethyl)amino]ethyl}ethanaminium and (C5H14N2)[MoS4] ⋅
H2O 5 (C5H14N2 is 1‐methylpiperazine‐1,4‐diium) are reported. The charge balancing cations in 1–3 are protonated methyl substituted propanamines, while the dications of 4 and 5 are derived from a tetraamine and a cyclic diamine respectively. The crystal structures of 1 to 5 consist of an unique tetrahedral [MoS4]2− dianion charge balanced by a crystallographically independent organic dication for all compounds excepting 1 which contains a pair of unique (2‐methylpropan‐2‐aminium) monocations. Although all the compounds are crystallized from aqueous solutions, 1 to 4 are anhydrous while 5 is a hemihydrate. In the crystal structures, the organic cations and the tetrasulfidomolybdate dianions are interlinked with the aid of several N−H⋅⋅⋅S and C−H⋅⋅⋅S hydrogen bonding interactions. In addition to N−H⋅⋅⋅S and C−H⋅⋅⋅S hydrogen bonds, compound 5 exhibits N−H⋅⋅⋅O and O−H⋅⋅⋅O hydrogen bonding interactions involving the H2O molecule, which interlinks pairs of anions with pairs of cations. Hirshfeld surface analyses were performed which reveal distortion of the [MoS4]2− tetrahedra, extensive S⋅⋅⋅H interactions between the anions and cations and also H⋅⋅⋅H contacts between the cations. A comparative study of the structural chemistry of thirty‐eight tetrasulfidomolybdates is described.
Assembly of Highly Functionalized Allylic Sulfones via a Stereoselective Pd‐Catalyzed Sequential C−C/C−S Cleavage and C−S Formation Process
Authors: Zhang Ning , Miao Lingling , Yang Yu , Duan Guohang , Shi Linlin , Hao Xin‐Qi , Song Mao‐Ping , Xu Yan , Zhu Xinju 
Published: May 2021

AbstractA Pd‐catalyzed sequential C−C/C−S cleavage and C−S formation approach for highly functionalized allylic sulfones synthesis of vinylcyclopropanes with p‐tosylmethyl isocyanide has been developed under mild conditions. Importantly, the reaction of modular VCPs and TosMIC would give access to (E)‐allylic sulfones in a stereoselective and regioselective fashion onto the in situ formed Pd intermediate. The current protocol featured broad substrate scope, operational convenience, and gram‐scale production.
Ligand Structure and Topology Effects in Complexation Selectivity of Am3+ and Eu3+ with ′O′, ′N′ and ′S′ Heterocyclic Diamides: A DFT Study
Authors: Bhattacharyya Arunasis , Mohapatra Prasanta K. 
Published: May 2021

AbstractThe separation of lanthanides from trivalent actinides is a challenging topic at the back end of nuclear fuel cycle. Soft donor ligands have been proposed for the effective separation of lanthanide from trivalent actinides. However, many soft donor ligands are not found very effective while some others have shown great promise. In this connection, donor atom softness ligand stereochemistry, donor atom size, rigidity of rings, etc. have been quite important in deciding the selectivity. The present work deals with the density functional theoretical calculations on the complexation of Am3+ and Eu3+ with a series of tridentate diamide derivatives having the central coordinating atom as ‘O’, ‘N’ and ‘S’ with varying structural rigidity. The results indicated shorter ‘M−N’ and ‘M−S’ bond distances in the Am3+ complexes as compared to those in the respective Eu3+ complexes of the ligands where the structural rigidity is minimum. However, overall the selectivity is the combined effect of the interaction of two lateral amidic oxygen atoms and the central donor atom, which is significantly affected depending upon the structure of the ligands with same donor centres. Gibb's free energy values were calculated for the complexation with all the ligands which was used to predict the selectivity. One of the ligand having ‘S’ as the central donor atom found to be most selective for Am3+ over Eu3+.
Energy‐based time equivalent approach for evaluating the fire resistance of timber components exposed to realistic design fire curves
Authors: Zhang Yongwang , Wang Lu , Chen Li 
Published: May 2021

SummaryAccording to the concept of performance‐based design, the fire safety design of the timber structures should be focused on the actual design fire, which represents the realistic fire situation in a given building. However, the current prescriptive only provides a method for evaluating the fire resistance of timber components under standard fire. This paper proposed an energy‐based time equivalent approach (EBTEA) for evaluating the fire resistance of the timber components in realistic design fire scenarios. As an alternative, this method was based on the principle of energy equivalence so that the fire resistance design of timber components exposed to realistic fires was standardized, which can make fire resistance rating database available under standard fire exposure and promote performance‐based design. The validity of the method was verified by comparing the predicted values of EBTEA with the existing values obtained from the nonlinear finite element analysis. The proposed method was further simplified by analyzing the key factors of energy equivalence and using nonlinear fitting methods to facilitate the use of designers. The simplified EBTEA can predict equivalent fire resistance of timber components under realistic design fire scenarios.
Secondary prevention of congenital cytomegalovirus infection with valacyclovir following maternal primary infection in early pregnancy
Authors: Faure‐Bardon V. , Fourgeaud J. , Stirnemann J. , Leruez‐Ville M. , Ville Y. 
Published: May 2021

ABSTRACTObjectiveCytomegalovirus (CMV) maternal primary infection (MPI) in early pregnancy is the main risk factor for congenital CMV (cCMV) infection with long‐term sequelae. Our aim was to evaluate, in a single center offering CMV serology screening at 11–14 gestational weeks, secondary prevention of cCMV by administration of high‐dosage maternal oral valacyclovir (VACV) in the first trimester of pregnancy.MethodsThis was a case–control study in a longitudinal cohort of pregnancies with CMV‐MPI diagnosed prior to 14 weeks of gestation by serology screening (immunoglobulin (Ig) M and IgG measurement and IgG avidity) between 2009 and 2020. From October 2019 onwards, all women presenting at our center with MPI before 14 weeks' gestation were offered treatment with high‐dosage oral VACV (8 g/day, 4 g twice/day). We used propensity score matching to compare fetal infection rates in cases treated with maternal oral VACV (8 g/day) with those in untreated controls. Fetal infection was assessed following amniocentesis at 17–22 weeks of gestation, by polymerase chain reaction (PCR) analysis of amniotic fluid for viral DNA.ResultsOf 310 cases of CMV‐MPI identified, 269 underwent amniocentesis for PCR. Of these, 66 were offered, and 65 accepted, treatment with VACV. From the remaining untreated cases, we selected 65 controls, matched for proportion of periconceptional infections and gestational age at amniocentesis. VACV was initiated at a median gestational age of 12.71 (interquartile range (IQR), 10.00–13.86) weeks and the median duration of treatment was 35 (IQR, 26–54) days. On multivariate logistic regression, fetal infection was lower in the treated group (odds ratio, 0.318 (95% CI, 0.120–0.841); P = 0.021). One treated patient developed acute renal failure 4 weeks after initiation of VACV therapy, but this resolved within 5 days after treatment was stopped.ConclusionThis study confirms the acceptability, tolerance and benefit of secondary prevention by VACV of cCMV infection in a clinical setting with a well‐established routine maternal serum screening policy in the first trimester of pregnancy. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
Co‐creating knowledge, policy, and practice: A call to advance Water Policy Lab process
Authors: Ojha Hemant , Maheshwari Basant , Bhattarai Basundhara 
Published: May 2021

AbstractNumerous scientific reports have established that the water future of humanity and the entire earth system is at risk. Solving contested water problems require new ways of harnessing dialogues, reflections, empathy, research, and visions. Too often, water policies and practices tend to take shortcuts, missing out on the benefits these powerful social learning processes can bring towards water justice and sustainability. This editorial presents a Water Policy Lab approach to initiate dialogue among those who are concerned with this dual crisis—of escalating water insecurity and knowledge not being linked well to water policy and practice.