bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brønsted Acid Catalyzed Dearomatization by Intramolecular Hydroalkoxylation/Claisen Rearrangement: Diastereo‐ and Enantioselective Synthesis of Spirolactams
Authors: Chen Peng‐Fei , Zhou Bo , Wu Peng , Wang Binju , Ye Long‐Wu 
Published: October 2021

AbstractDescribed herein is a novel Brønsted acid catalyzed intramolecular hydroalkoxylation/Claisen rearrangement, allowing the practical and atom‐economic synthesis of a range of valuable spirolactams from readily available ynamides in generally good to excellent yields with excellent diastereoselectivities and broad substrate scope. Importantly, an unexpected dearomatization of nonactivated arenes and heteroaromatic compounds is involved in this tandem sequence. Moreover, an asymmetric version of this tandem cyclization was also achieved by efficient kinetic resolution by chiral phosphoric acid catalysis. In addition, the [3,3]‐rearrangement is shown to be kinetically preferred over the related [1,3]‐rearrangement by theoretical calculations.
Biomimics of phenazine oxidase activity of a cobalt (III)‐dipyridylamine complex: Spectroscopic, structural, and computational studies†
Authors: Mahato Rajani Kanta , Das Soumik , Joshi Mayank , Choudhury Angshuman Roy , Misra Anirban , Biswas Bhaskar 
Published: October 2021

AbstractThis manuscript demonstrates the synthesis, structural characterization, computational studies, and biomimics of the phenazine oxidase activity of a newly designed cobalt (III) complex, [Co (dpa)(dpa‐H+)(N3)2]Cl2 (1) [dpa = 2,2′‐dipyridylamine] under an aerobic condition. The crystal structure analysis reveals that the cobalt (III) center adopts an octahedral geometry, and the complex forms a beautiful supramolecular framework through noncovalent interactions. The cobalt (III) catalyst turns out to be a promising catalyst for the oxidative coupling of o‐phenylenediamine (OPD) in oxygen‐saturated methanol with an excellent turnover number, kcat = 7.85 × 103 h−1. Spectrophotometric, electrochemical, mass spectrometry, and computational analysis ensure that the course of catalysis undergoes through a catalyst‐substrate complexation, facilitating the development of cobalt‐iminobenzoquinone species in the solution. The computational calculations employing the density functional theory (DFT) throw a light to the mechanistic insights of the phenazine oxidase mimics. ETS‐NOCV (extended transition state‐natural orbitals for chemical valence) plots of the reactive intermediates portray the coordination‐driven depletion of electron density from the nitrogens of OPD to cobalt center leading to the enhancement of electrophilic character on para‐positioned C‐atoms with respect to N‐atoms of OPD, therby catalyzing the nucleophilic attack by second OPD to produce the oxidation product, 2,3‐diaminophenazine (DAP). Interestingly, we are able to isolate the oxidation product of the OPD oxidation reaction as a hydrated chloride salt, DAPH+Cl− ·3H2O (2). The crystal engineering perspectives of 2 attribute the intriguing fate of the secondary chlorides for the stabilization of the oxidation product in crystalline phase.
Rheological kinetics of ferrocenylsilane functionalized polyurethanes based on 4,4'‐methylenediphenyl diisocyanate for advanced energetic materials
Authors: Lucio Beatriz , de la Fuente José Luis 
Published: October 2021

Abstract4,4′‐Methylenediphenyl diisocyanate (4,4'‐MDI) is a symmetric aromatic isocyanate commonly used as a curing agent in the production of polyurethanes (PUs). The chemorheology and kinetics of its reaction with a metallocenic‐prepolymer derivative from hydroxyl‐terminated polybutadiene (HTPB) is studied in bulk and under isothermal conditions at 50–80°C by means of rheological measurements. The viscosity of the initial part of the PU formation, the pregel stage governed by viscous behavior, is modeled through the Arrhenius rheokinetic model. This thermoplastic elastomer undergoes gelation, a transition that is analyzed in depth together with predictions according to percolation theory. The gel point (tgel) is determined from the intersection in tan δ versus curing time for different shear frequencies. From the viscoelastic properties, like the elastic storage modulus (G'), the conversion degree is determined, and the entire polymerization process is modeled through the Kamal‐Sourour and Sato kinetic expressions. Significant variation in the reaction orders and the activation energies might reveal a change in the process mechanism, depending on the temperature. This work demonstrates that an indirect method makes it possible to gain relevant knowledge about the chemistry of these thermoplastic PUs during curing, which is essential for their manufacturing. This study merits attention for the development of a new generation of high‐performance binders with great potential in aerospace propulsion.
Residual stress and thermal properties of rubber‐modified epoxy systems for semiconductor package
Authors: Qu Chunyan , Zhang Xiao , Wang Dezhi , Fan Xupeng , Li Hongfeng , Liu Changwei , Feng Hao , Wang Ruikun , Guo Ke , Tian Yanan , Liu Yang 
Published: October 2021

AbstractThe thermal and mechanical breakage of epoxy coating due to easy cracking, poor toughness, and large residual stress, occurring during curing and thermal aging process, is the key factor responsible for damage of silicon device on semiconductor elements. In this study, modified epoxy resins containing an imide ring and polybutadiene rubber‐modified epoxy resin used as the toughening agents were prepared to investigate the residual stress generated during the curing and thermal aging process. The curing process and the thermal properties of the modified epoxy systems were assessed by differential scanning calorimetry and rotational rheometry, dynamic thermomechanical analysis, thermomechanical analysis, and thermogravimetric analysis. A thin film stress analyzer was used to analyze the changes in thermal stress of the modified epoxy systems during curing and cyclic stress and compared with the data from theoretical calculation. The results show that, with the increase in content of the toughening agent, the toughness of the modified epoxy systems was significantly improved, and the curing and thermal cycle stresses could be simultaneously reduced. Besides, we also envision the extension of the comprehensive evaluation method for residual stress described in this study to enable the modification of epoxy coatings prepared using a toughening agent, in the near future.
Hybrids from silazane and allyl‐containing benzoxazine for low‐curing temperature and high‐flame retardance
Authors: Ai Tao , Zhang Yao , Zhong Danni , Yang Zecheng , Zong Jingshan , Niu Yanhui 
Published: October 2021

AbstractSilicon hybrid benzoxazine has good flame retardance, but generally these hybrid polymer' curing temperature is higher than 220°C, limiting its application in the field of electronics. In this study, under Nickel acetylacetonate catalyzed, a new hybrid benzoxazine was synthesized using the copolymerization of polysilazane and allyl containing benzoxazine. Differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR) studied the curing behavior of this hybrid benzoxazine. The results of DSC and FTIR indicated that the curing temperature of this hybrid benzoxazine can decrease from 269 to 182°C, the main reaction with this hybrid benzoxazine is amine‐catalyzed oxazine ring‐ opening and the hydrosilylation reaction. The thermal stability of hybrid benzoxazine after cured was studied by a thermogravimetric analyzer. The results of thermogravimetric experiments demonstrated that this hybrid benzoxazine's char yield can increase from 25.57% to 66.11% (159% increase). The flame retardancy of glass fiber reinforced hybrid benzoxazine was studied by the UL‐94 flame test. The glass fiber reinforced hybrid benzoxazine composite show a V‐0 result in the UL‐94 test. This work provides a new hybrid benzoxazine with low‐curing temperature, ultrahigh char yield, and great flame retardance.
Resveratrol ameliorates toxic effects of cadmium on placental development in mouse placenta and human trophoblast cells
Authors: Wang Wenjie , Liu Guiying , Jiang Xuelian , Wu Guimei 
Published: October 2021

AbstractBackgroundCadmium (Cd) is a common heavy metal pollutant. Prenatal exposure to Cd results in adverse effects on fetal development. Placental apoptosis, inflammation, and epigenetic disruption have been implicated in Cd‐induced placental toxicity. Resveratrol (Res) is a naturally occurring polyphenol with anti‐apoptotic, anti‐inflammatory, and epigenetic regulatory activities. In present study, the effects of Res on placental toxicity induced by Cd were evaluated.MethodsPregnant CD‐1 mice were fed with base diet containing 0.2% Res started on gestational day 0 (GD0), and intraperitoneally injected with 4.5 mg/kg CdCl2 or saline once on GD9. JEG‐3 cells were treated with 20 μM Res for 24 hr in the absence or presence of 20 μM CdCl2 for the second 12 hr. The fetal outcomes, the apoptosis in placenta and JEG‐3 cells, the expression of inflammatory cytokines and chemokines including tumor necrosis factor‐α (TNF‐α), interferon‐gamma (IFN‐γ), monocyte chemoattractant protein 1 (MCP‐1), macrophage inflammatory protein‐2 (MIP‐2) and chemokine (C–X–C motif) ligand 1 (KC), and expression of endoplasmic reticulum (ER) stress markers were evaluated. The expression and activities of DNA methyltransferase (DNMT), and the activation of Akt signaling pathway were detected.ResultsCd exposure resulted in decreased fetal weight and crown‐rump length while Res ameliorated these outcomes. Res suppressed Cd‐induced apoptosis in placenta and JEG‐3 cells, and decreased Cd‐induced expression of TNF‐α, IFN‐γ, MCP‐1, MIP‐2, and KC in placenta. Cd greatly increased ER stress in placenta in mice, which was partially ameliorated by Res treatment. Res decreased Cd‐induced upregulation of DNMT activity and suppressed Cd‐induced expression of DNMT3B. Res restored estradiol secretion, enhances activity and protein levels of SIRT1 and inhibited Cd‐induced activation of Akt signaling pathway.ConclusionRes ameliorated Cd‐induced placental toxicity and regulated DNMT3 expression and PI3K/Akt pathway activation.
Overview on immobilization of enzymes on synthetic polymeric nanofibers fabricated by electrospinning
Authors: Rather Anjum Hamid , Khan Rumysa Saleem , Wani Taha Umair , Beigh Mushtaq A. , Sheikh Faheem A. 
Published: October 2021

AbstractThe arrangement and type of support has a significant impact on the efficiency of immobilized enzymes. 1‐dimensional fibrous materials can be one of the most desirable supports for enzyme immobilization. This is due to their high surface area to volume ratio, internal porosity, ease of handling, and high mechanical stability, all of which allow a higher enzyme loading, release and finally lead to better catalytic efficiency. Fortunately, the enzymes can reside inside individual nanofibers to remain encapsulated and retain their three‐dimensional structure. These properties can protect the enzyme's tolerance against harsh conditions such as pH variations and high temperature, and this can probably enhance the enzyme's stability. This review article will discuss the immobilization of enzymes on synthetic polymers, which are fabricated into nanofibers by electrospinning. This technique is rapidly gaining popularity as one of the most practical ways to fibricate polymer, metal oxide, and composite micro or nanofibers. As a result, there is interest in using nanofibers to immobilize enzymes. Furthermore, present research on electrospun nanofibers for enzyme immobilization is primarily limited to the lab scale and industrial scale is still challanging. The primary future research objectives of this paper is to investigate the use of electrospun nanofibers for enzyme immobilization, which includes increasing yield to transfer biological products into commercial applications.
Cross‐cultural prevalence of sleep quality and psychological distress in healthcare workers during COVID‐19 pandemic
Authors: Khan Hamza Rafique , Ashraf Farzana , Ullah Irfan , Tahir Muhammad Junaid , Dominari Asimina , Shoib Sheikh , Naeem Hamna , Reddy Gowry , Mukherjee Pramit , Akram Ifrah , Kamada Sudha , Memon Roshni Riaz , Khan M. Muzzamil Yasin , Raut Sumit , Shalaby Mahmoud Mohamed Mohamed , Anwar Rana Usman , Farooq Maheen , Soparia Krupa Ketankumar , Ramalho Rodrigo , Lin Chung‐Ying , Pakpour Amir H. 
Published: October 2021

AbstractBackgroundPoor quality sleep and emotional disturbances are expected in times of crisis. COVID‐19 has severely impacted healthcare worldwide and with that comes the concern about its effects on healthcare workers. The purpose of the present study was to assess sleep quality and psychological distress in healthcare workers during the COVID‐19 pandemic.MethodsThe present work is a multi‐centric cross‐sectional study targeting healthcare workers from India, Pakistan, and Nepal. It used an online version of the Pittsburg Sleep Quality Index and the General Health Questionnaire, and data were analyzed using SPSS V.24.ResultsA total of 1790 participants completed the questionnaire. Of the 1790 participants, 57% reported poor sleep quality, and 10% reported a high level of psychological distress. A cross‐cultural comparison found some differences between the different groups of participants. The details of the differences were further explored in the article.ConclusionThe present study highlights that a significant proportion of healthcare workers are affected by poor sleep quality and psychological distress during the COVID‐19 pandemic. It also emphasizes the imperative to provide them with psychosocial support to avoid potential short‐ and long‐term psychological consequences of these troubling times.
Analysis of the predictive variables of socially responsible consumption
Authors: Palacios‐González María Manuela , Chamorro‐Mera Antonio 
Published: October 2021

AbstractAchieving the Sustainable Development Goals proposed by the UN for 2030 implies designing strategies that promote socially responsible consumption. The effectiveness of these strategies will depend on understanding the variables that influence socially responsible behaviour. We must also bear in mind that these variables and this behaviour are of a dynamic, multidimensional and non‐universal nature. The objective of this work is to identify how three attitudinal variables (emotional engagement, perceived consumer effectiveness and perception of personal gain) influence socially responsible consumption, through a model of structural equations. To do this, a survey was conducted of 415 Spanish consumers. The results reflect that socially responsible consumption is mainly explained by emotional engagement and to a lesser extent by perceived consumer effectiveness. In contrast, it is not influenced by perception of personal gain.
Beyond ethics: The transformational power of overlapping motivations in implementing strategic sustainability actions
Authors: Bonilla‐Priego Maria Jesus , Nájera‐Sánchez Juan‐José , Font Xavier 
Published: October 2021

AbstractWe develop a methodology to identify patterns between sustainability motivations, actions and engagement. We apply this methodology to analyse a 3 1/2‐year intervention that yielded 151 sustainability actions undertaken by 46 outbound tour operators. We find three aspects that can be explained by the tour operators' motivations to act sustainably, namely, a connection between: (i) the actions taken in the context of the organisation's business model, (ii) the intensity of the approach, measured by the resources invested in it and the operator's commitment level and (iii) the evolution of the response. These patterns demonstrate how ethical motivations are common and a precondition to acting sustainably, but, in themselves, these motivations are not sufficient to integrate sustainability practices into the core business or to maintain commitment over time. It is the combination of a high ethical commitment with clear strategic intent, materialised in commercial and operational motivations, that increases the connectedness, and intensity, of sustainability actions amongst ethically committed firms.
Executive compensation and sustainable business practices: The moderating role of sustainability‐based compensation
Authors: Adu Douglas A. , Flynn Antoinette , Grey Colette 
Published: October 2021

AbstractThis study seeks to contribute to the extant business strategy and the environment literature by investigating the effect of CEO pay and executive compensation (EC) on sustainable business practice (SBPs). It also distinctively ascertains whether the pay‐for‐sustainability sensitivity (PSS) is reinforced in firms with sustainability‐based compensation (SBC) policy. Using a sample of 262 UK listed firms from 2009 to 2018, our findings are threefold. First, the findings reveal that both CEO pay and EC variables have positive effect on all SBP measures, except CO2 reduction performance where the link is negative. Second, the study shows that the PSS is reinforced for firms that implement SBC policy. Finally, we detect that both the PSS and the moderation effect of SBC on the PSS are higher in the symbolic construct of SBPs than the actual measures. The results support insights drawn from neo‐institutional theory. The findings have key implications for regulators and policy makers.
Environmental labeling certification and firm environmental and financial performance: A resource management perspective
Authors: He Duojun , Ren Shenggang , Zeng Huixiang 
Published: October 2021

AbstractEnvironmental labeling certification (ELC) is a new type of voluntary environmental regulation for firm environmental governance. This study examines the impacts of ELC on firm environmental performance (EP) and financial performance (FP) from the resource management perspective. Based on a sample of 1325 Chinese A‐share listed manufacturing firms from 2008 to 2016 with 9972 firm‐year observations, it is found that ELC improves firm EP, but has a limited impact on firm FP. Specifically, ELC is found to have a significant impact on firm annual operating income (AOI) and Tobin's q, but has no impact on return on assets (ROA). Therefore, ELC has not yet promoted firms to achieve a win‐win situation between EP and FP. Further analysis reveals that ELC can trigger environmental innovation offsets, but the effect of environmental innovation offsets is weak at present. Moreover, the impact of ELC on firm FP reflects the heterogeneity of the ownership structure. This study not only contributes to the existing literature, but also makes extensive practical contributions.
A novel upregulated LncRNA‐AC026150.8 promotes chemo‐resistance and predicts poor prognosis in acute myeloid leukemia
Authors: Zhang Henan , Zhao Yue , Liu Xuan , Liu Yusi , Wang Xiaohui , Fu Yu , Fu Shuang , Zhang Jihong 
Published: October 2021

AbstractBackgroundAML is a common hematological malignancy with poor prognosis, the pathogenesis is still unclear. lncRNA takes part in occurrence and development of AML. This research aims to explore new differentially expressed lncRNAs and their effects on AML.MethodsDatabase‐based bioinformatics analysis was performed to screen differentially expressed lncRNA in AML, real‐time PCR was used to analyze gene expression. Kaplan–Meier survival analysis was performed to determine prognostic effect of AC026150.8 in AML. The cell drug resistance experiment was performed to test effect of AC026150.8 on chemo‐resistance of AML cells. Catrapid online software and RNA pull‐down, mass spectrometry, western‐blot were used to predict and verify the combination of AC026150.8 and RNA splicing factors.ResultsAC026150.8 was upregulated in AML patients and related to poor prognosis. High leukocyte counts, FAB classification, MLL‐AF9 expression and NPM1 mutations were associated with high AC026150.8 expression. Upregulated of AC026150.8 increased the drug resistance of AML cells. AC026150.8 could be combined with splicing factor PCBP1.ConclusionsFor the first time, our study found that the upregulated AC026150.8 in AML is related to poor prognosis, overexpression of AC026150.8 could increase drug resistance of AML cells, and confirmed its scaffolding effect in combination with splicing factors. It is necessary to further study AC026150.8 and its downstream target genes to clarify the mechanism of AC026150.8 in AML.
Using rich data to inform student mental health practice and policy
Authors: Broglia Emma , Bewick Bridgette , Barkham Michael 
Published: October 2021

AbstractThe collection and use of rich data on student mental health are necessary to inform practice and policy, and ultimately lead to improved outcomes. Here, rich data refers to the combination of large and representative data sets, as well as detailed accounts of lived experiences and perspectives. We argue that such data are necessary to respond to the diverse and ever‐changing needs of students while building an evidence base for current and emerging services and staff roles. We provide suggestions for moving towards these goals, argue for adopting diverse research methods to yield data‐informed practice and policy, and introduce a special section in Counselling and Psychotherapy Research to reflect this agenda.
Tasty for everyone: Using horizontal metaphor in food evaluations
Authors: Cho Yoon‐Na 
Published: October 2021

AbstractThis article examines the effects of embodied cognition related to a spatial horizontal metaphor, whereby consumers seem to associate horizontal space with the “left being bad” and “right being good.” Across four studies, we extend prior research on embodied cognition by theorizing how the physical location of products, the usage of the left or right hand, and the product valence interact to influence consumer evaluations. The findings reveal a complex nature of effects associated with the horizontal metaphor, valence of food, as well as approach‐avoidance orientation. These findings have important theoretical and practical implications.
Pulmonary percutaneous valve implantation in large native right ventricular outflow tract with 32 mm Myval transcatheter heart valve
Authors: Rodríguez Ogando Alejandro , Ballesteros Fernando , Martínez Jose Luis Zunzunegui 
Published: October 2021

AbstractPulmonary percutaneous valve implantation (PPVI) is feasible with satisfactory mid‐term results in patients with native right ventricular outflow tract (RVOT) and has been increasingly used instead of surgically implantable pulmonary valves. Creating a stable landing zone with a diameter less than the largest commercially available valve (previously available 29 mm and currently available 32 mm) is crucial for technical success of the procedure, limiting the number of suitable candidates for PPVI. We report the case of PPVI with a 32 mm Myval transcatheter heart valve in a patient with a large native RVOT (pre‐stented with AndraStent XXL mounted on a 35 × 60 mm valve balloon catheter) lesion who had Tetralogy of Fallot surgically corrected. The post‐procedural outcomes of this case were satisfactory with no complications reported during the hospital stay.