bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decarboxylation‐Induced Defects in MOF‐Derived Single Cobalt Atom@Carbon Electrocatalysts for Efficient Oxygen Reduction
Authors: Yuan Shuai , Zhang Jinwei , Hu Linyu , Li Jiani , Li Siwu , Gao Yanan , Zhang Qinghua , Gu Lin , Yang Wenxiu , Feng Xiao , Wang Bo 
Published: July 2021

AbstractDeveloping transition metal single‐atom catalysts (SACs) for oxygen reduction reaction (ORR) is of great importance. Zeolitic imidazolate frameworks (ZIFs) as a subgroup of metal‐organic frameworks (MOFs) are distinguished as SAC precursors, due to their large porosity and N content. However, the activity of the formed metal sites is limited. Herein, we report a decarboxylation‐induced defects strategy to improve their intrinsic activity via increasing the defect density. Carboxylate/amide mixed‐linker MOF (DMOF) was chosen to produce defective Co SACs (Co@DMOF) by gas‐transport of Co species to DMOF upon heating. Comparing with ZIF‐8 derived SAC (Co@ZIF‐8‐900), Co@DMOF‐900 with more defects yet one fifth Co content and similar specific double‐layer capacitance show better ORR activity and eight times higher turnover frequency (2.015 e s−1 site−1). Quantum calculation confirms the defects can weaken the adsorption free energy of OOH on Co sites and further boost the ORR process.
Construction of waterborne superhydrophobic coatings with controlled water‐droplet adhesion
Authors: Yang Jixiang , Fan Haoyu , Zhou Yuqian , Liang Huiyun , Zeng Liheng , Xie Dong , Guo Tianying 
Published: August 2021

AbstractA novel strategy for fabricating waterborne superhydrophobic coatings with controllable adhesive force to water‐droplet has been developed by blending the amphiphilic silica nanoparticles modified using thermally sensitive amphiphilic polymers with polymer latex, which could be applied for self‐cleaning or no loss transfer of microdroplets. And a theoretical analysis of the relationship between the surface chemical composition and the water‐droplet adhesion of the superhydrophobic nanocomposite coating is proposed.
Synthesis and property study of a polyether tercopolymer scale inhibitor with carboxyl and sulfonic acid groups
Authors: Li Hui , Ren Dajun , Zhuang Mengjuan , Wang Zhaobo , Zhang Xiaoqing , Zhang Shuqin , Chen Wangsheng 
Published: August 2021

AbstractA new environment‐friendly hydrophilic terpolymer of PAA‐AEO‐SAS was synthesized by free radical polymerization using acrylic acid (AA), aliphatic alcohol polyoxyethylene ether (AEO) and sodium allyl sulfonate (SAS). The structure and molecular weight were characterized by FTIR, 1H‐NMR and GPC. The optimal monomer ratio, initiator level, reaction temperature and time for the synthesis of PAA‐AEO‐SAS were determined by the controlled variable method, and the inhibition performance on calcium carbonate (CaCO3) scale at different water bath temperature, pH, Ca2+ concentration and time were investigated by the static scale inhibition method. And the scales were analyzed by XRD and SEM. The results showed that the inhibitor had the best performance when the molar ratio of AA‐AEO/AA/SAS was 1:5:1, initiator was 4 mol%, the polymerization temperature was 85°C, and the reaction time was 2 h. Under the optimal synthesis conditions, the maximum inhibition efficiency was 90% (18 mg/L) and the Mw and Mn of PAA‐AEO‐SAS were 1546 and 1326, respectively. In addition, the surface morphology of calcium scale with the inhibitor was significantly changed from the characterization results. In short, the combination of multiple functional groups allowed the application of PAA‐AEO‐SAS in the complicated and challenging circumstances.
Effect of one‐session focused attention meditation on the working memory capacity of meditation novices: A functional near‐infrared spectroscopy study
Authors: Yamaya Noriki , Tsuchiya Kenji , Takizawa Ibuki , Shimoda Kaori , Kitazawa Kazuki , Tozato Fusae 
Published: August 2021

AbstractIntroductionPrevious studies have revealed that one‐session focused attention meditation (FAM) can improve top‐down attention control, which is one of the factors of working memory capacity (WMC). In addition, FAM shares various neural substrates, including the dorsolateral prefrontal cortex (DLPFC), with WMC. Thus, we hypothesized that one‐session FAM would improve WMC by activating the DLPFC evoked by the top‐down attention control. In this study, we examined whether FAM modified WMC in individuals with little to no meditation experience.MethodsThe participants were randomly assigned to either the FAM group (N = 13) or the control group (N = 17) who engaged in random thinking (i.e., mind‐wandering). Before and after each 15‐min intervention, the participants’ WMC was measured according to the total number of correct answers in the Reading Span Test. During each intervention, functional near‐infrared spectroscopy was employed to measure the blood flow in the participants’ DLPFC and determine the top‐down attention control effect.ResultsIn the FAM group, WMC increased, and the bilateral DLPFC was activated during the intervention. As for the control group, WMC decreased after the intervention, and the bilateral DLPFC was not activated during the intervention. A correlation was also found among all participants between the increase in WMC and the activation of the bilateral DLPFC.ConclusionThe study findings suggest that top‐down attention control during FAM can activate the bilateral DLPFC and increase WMC among meditation novices.
Coping strategies, optimism, and resilience factors associated with mental health outcomes among medical residents exposed to coronavirus disease 2019 in Qatar
Authors: Smida Malek , Khoodoruth Mohamed Adil Shah , Al‐Nuaimi Saleem Khaldoon , Al‐Salihy Zerak , Ghaffar Adeel , Khoodoruth Widaad Nuzhah Chut‐kai , Mohammed Mohammed Faisal Hamad , Ouanes Sami 
Published: August 2021

AbstractObjectiveThe aim of this study is to examine the association between coping strategies, resilience, optimism and different mental health outcomes like stress, anxiety, and depression among the medical residents’ during the COVID‐19 pandemic, with consideration of different factors like seniority, frontliner, gender, and coping style.MethodsAn electronic survey was sent to all medical residents in Qatar. Depression, anxiety, and stress were assessed by the DASS‐21. Professional quality of life was measured by the ProQOL scale. The coping mechanisms were assessed with the Brief‐COPE, and resilience was measured by the Brief Resilience Scale.ResultsThe most commonly used coping strategies were acceptance, religion, and active coping. The avoidant coping style scores were higher among junior residents (p = .032) and non‐COVID‐19 frontliners (p = .039). Optimism LOT‐R score was higher in senior than in junior residents (p < .001). Lower avoidant coping scores, higher optimism, and higher resilience were associated with lower stress, anxiety, and depressive symptoms.ConclusionIt seems that avoidant coping styles can exacerbate depressive, anxiety, and stress symptoms in medical residents amidst the COVID‐19 pandemic. Strategies promoting optimism, resilience, and approach coping styles can decrease the mental health burden of the pandemic on medical residents.
Characteristics and outcomes of unsuccessful percutaneous coronary intervention
Authors: Biswas Sinjini , Dinh Diem , Duffy Stephen J. , Brennan Angela , Liew Danny , Chan William , Cox Nicholas , Reid Christopher M. , Lefkovits Jeffrey , Stub Dion 
Published: July 2021

AbstractObjectivesTo examine predictors and outcomes of unsuccessful percutaneous coronary intervention (PCI) cases in a contemporary Australian registry cohort.BackgroundWith improvements in techniques and pharmacotherapy in PCI, more complex lesions in older patients are now being attempted. In the context of PCI performance assessment, there are limited data regarding the characteristics and outcomes of unsuccessful PCI.MethodWe prospectively collected data on patients undergoing single‐lesion PCI between 2013 and 2017 who were enrolled in the multi‐center Victorian Cardiac Outcomes Registry. Procedures were divided into two groups by whether or not PCI was deemed successful at the end of the procedure using a pre‐specified definition.ResultsThere were 34,383 single‐lesion PCI performed, of which 18,644 (54.2%) were for acute coronary syndromes. Of the study cohort, 2080 patients (6.0%) had an unsuccessful PCI – these patients were older, more likely to have previous stroke, PCI, severe left ventricular dysfunction and chronic kidney disease (all p < 0.001). The procedure was also more likely to be performed for stable angina (p < 0.001). Chronic total occlusion PCI made up 31% of unsuccessful PCI cases. Unsuccessful PCI was itself associated with higher in‐hospital and 30‐day mortality and MACE (all p < 0.001). 4.9% of unsuccessful PCIs led to unplanned in‐hospital bypass surgery (compared to 0.2% in successful PCIs, p < 0.001).ConclusionOur study highlights that even in contemporary PCI practice, more than 1 in 20 PCI attempts are unsuccessful. Lack of procedural success has a strong influence on patient outcomes. Monitoring rates of unsuccessful cases is an important quality assurance tool.
Impact of gender on in‐hospital mortality and 90‐day readmissions in patients undergoing transcatheter edge‐to‐edge mitral valve repair: Analysis from the National Readmission Database
Authors: Guddeti Raviteja R. , Pajjuru Venkata S. , Walters Ryan W. , Garcia Santiago A. , Alla Venkata M. 
Published: August 2021

AbstractBackgroundPatients undergoing transcatheter edge‐to‐edge mitral valve repair (TEER) carry a high risk of rehospitalization due to disease, procedure, patient, hospital, and system related factors.AimsWe aimed to explore the impact of gender on in‐hospital mortality and 90‐day readmissions in patients undergoing TEER.MethodsWe utilized the National Readmission Database from 2012 to 2018 to identify individuals who underwent TEER for mitral regurgitation. Gender‐based differences in in‐hospital mortality and 90‐day readmissions were explored using multivariable logistic regression models.ResultsBetween 2012 and 2018, an estimated 21,415 TEER procedural hospitalizations were identified, of which 9893 (46.2%) were in women and 11,522 (53.8%) were in men. Compared with men, women were older, from a lower socioeconomic status but had a lower co‐morbidity burden. In‐hospital mortality rate during the index hospitalization was similar in women and men (2.1% vs. 2.1%, p = 0.908). Ninety‐day all‐cause and heart failure readmission rates were significantly higher in women compared to men (30.2% vs. 25.4%; p < 0.001 and 28.1% vs. 23.9%; p = 0.020 respectively). In a multivariable analysis, women had 36% greater odds of 90‐day readmission compared to men (adjusted odds ratio [aOR] 1.36, 95% CI: 1.22–1.52; p < 0.001). Trend analysis revealed no significant improvement in rates of 90‐day readmission during the observation period for men or women (p = 0.245, p = 0.429, respectively).ConclusionsFollowing TEER, there has been no significant improvement in 90‐day readmission rates between 2012 and 2018. Female gender is associated with higher 90‐day all‐cause and heart failure readmission rates.
Elucidating the Role of Aqueous Solvent in an Iron‐Based Water Oxidation System by DFT‐based Molecular Simulation
Authors: Li Ying‐Ying , Meijer Evert Jan , Liao Rong‐Zhen 
Published: August 2021

AbstractWater solvent plays an important role in catalytic water oxidation to dioxygen, in particular in the O−O bond formation process. In this work, we revisit the mechanism of O−O bond formation catalyzed by a mononuclear iron catalyst [Cl−FeIII(dpa)−Cl]+, in a DFT‐based molecular dynamics (DFT‐MD) study that incorporates explicit solvent and thermal fluctuations. Two possible mechanisms for the crucial O−O bond formation, namely water nucleophilic attack (WNA) and nitrate nucleophilic attack (NNA) on the high‐valent FeV‐oxo moiety, were considered and found to have similar barriers (15 kcal/mol vs 16 kcal/mol). Comparison with static DFT calculations demonstrated the important role of water solvent molecules, especially for the NNA pathway. For this mechanism, the interaction of the negatively‐charged nitrate with solvent molecules is substantial, giving rise to a free energy barrier increase of 7.7 kcal/mol compared with static DFT calculations. The study suggests that for molecular water‐oxidation catalysts, the local aqueous solvation structure and its thermal fluctuations plays a significant role in the crucial O−O bond formation step. The study also elucidates the role of the nitrate ion as a co‐catalyst, a notion that may serve as a potential design rule for developing improved water oxidation catalysts.
Dual Doping of MoP with M(Mn,Fe) and S to Achieve High Hydrogen Evolution Reaction Activity in Both Acidic and Alkaline Media
Authors: El‐Refaei Sayed M. , Russo Patrícia A. , Schultz Thorsten , Koch Nobert , Pinna Nicola 
Published: August 2021

AbstractRational design of cost‐effective, high performance and stable hydrogen evolution reaction (HER) electrocatalysts in both acidic and alkaline media holds the key to the future hydrogen‐based economy. Herein, we introduce an effective approach of simultaneous non‐metal (S) and metal (Fe or Mn) doping of MoP to achieve excellent HER performance at different pH. The catalysts show remarkable overpotentials at −10 mA cm−2 of only 65 and 68 mV in 0.5 M H2SO4, and 50 and 51 mV in 1.0 M KOH, respectively, as well as much higher turnover frequencies compared to undoped MoP. Furthermore, the catalysts exhibit outstanding long‐term stability at a fixed current of −10 mA cm−2 for 40 h. The effects of both dopants, such as electronic structure modification and enhancement of the intrinsic activity, increase of the electrochemically active surface area, and formation of coordinatively unsaturated edge sites, act cooperatively to accelerate the HER at both pH media. Additionally, the presence of oxophilic Mn and Fe at the surface results in Mn or Fe oxide/hydroxide species that promote the dissociation of water molecules in alkaline electrolyte. This work introduces a facile and effective design principle that could pave the way towards engineering highly active HER catalysts for a wide pH range.
Two‐Step Deposition Approach for Lead Free (NH4)3Sb2I9 Perovskite Solar Cells with Enhanced Open Circuit Voltage and Performance
Authors: Kumar Praveen , Ahmad Khursheed , Dagar Janardan , Unger Eva , Mobin Shaikh M. 
Published: August 2021

AbstractIn recent years, development of lead (Pb) free perovskite solar cells (PSCs) has attracted the scientific community because of their stability in air and less toxic nature. Antimony (Sb) based perovskite like‐materials such as (CH3NH3)3Sb2I9 and (NH4)3Sb2I9 have been employed as light absorbers and showed promising features for photovoltaic applications. Herein, we have utilized (NH4)3Sb2I9 as light absorber for the construction of Pb free PSCs. Moreover, we have employed a modified two step procedure for the preparation of (NH4)3Sb2I9. The developed Pb free PSCs device (FTO/CL‐TiO2/m‐TiO2/(NH4)3Sb2I9/HTM/Au) exhibited enhanced power conversion efficiency (PCE) of 0.42 % with open circuit voltage (Voc) of 945 mV.
Transition Metal‐Catalyzed Hydroalkoxylation of Alkynes: An Overview
Authors: Nanda Santosh K. , Mallik Rosy 
Published: August 2021

AbstractOxygen‐bearing motifs, mainly the congener heterocycles are ubiquitous due to their presence in various natural products and bioactive scaffolds. Although in literature, several strategies have been developed for their synthesis, hydroalkoxylation of alkynes has come forward as a method of choice and has been used extensively. In particular, hydroalkoxylation of alkynes has gained enormous attention from the synthetic community due to the rapid access to a very useful and reactive synthetic intermediate like ‘enol ether’. Furthermore, to manifold the utility of these methods, reports have been developed elaborating the generation of ‘enol ether’ using hydroalkoxylation and their usage in various reactions in cascade or tandem manner. This review focuses on recent development on the hydroalkoxylation of alkynes for the synthesis of oxygen‐containing entities.
Are Heavy Pnictogen‐π Interactions Really “π Interactions”?
Authors: Schiavo Eduardo , Bhattacharyya Kalishankar , Mehring Michael , Auer Alexander A. 
Published: August 2021

AbstractThe noncovalent interactions of heavy pnictogens with π‐arenes play a fundamental role in fields like crystal engineering or catalysis. The strength of such bonds is based on an interplay between dispersion and donor/acceptor interactions, and is generally attributed to the presence of π‐arenes. Computational studies of the interaction between the heavy pnictogens As, Sb and Bi and cyclohexane, in comparison with previous studies on the interaction between heavy pnictogens and benzene, show that this concept probably has to be revised. A thorough analysis of all the different energetic components that play a role in these systems, carried out with state‐of‐the‐art computational methods, sheds light on how they influence one another and the effect that their interplay has on the overall system. Furthermore, the analysis of such interactions leads us to the unexpected finding that the presence of the pnictogen compounds strongly affects the conformational equilibrium of cyclohexane, reversing the relative stability of the chair and boat‐twist conformers, and thus suggesting a possible application of tuneable dispersion energy donors to stabilise the desired conformation.
Heterobimetallic Coinage Metal‐Ruthenium Complexes Supported by Anionic N‐Heterocyclic Carbenes
Authors: Planer Sebastian , Frosch Jenni , Koneczny Marvin , Trzybiński Damian , Woźniak Krzysztof , Grela Karol , Tamm Matthias 
Published: August 2021

AbstractThe lithium complexes [(WCA‐NHC)Li(toluene)] of anionic N‐heterocyclic carbenes with a weakly coordinating borate moiety (WCA‐NHC, WCA=B(C6F5)3, NHC=IDipp=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene) were used for the preparation of silver(I) or copper(I) WCA‐NHC complexes. While the reactions in THF with AgCl or CuCl afforded anionic mono‐ and dicarbene complexes with solvated lithium counterions [Li(THF)n]+ (n=3, 4), the reactions in toluene proceeded with elimination of LiCl and formation of the neutral phosphine and arene complexes [(WCA‐NHC)M(PPh3)] and [(WCA‐NHC)M(η2‐toluene)] (M=Ag, Cu). The latter were used for the preparation of chlorido‐ and iodido‐bridged heterobimetallic Ag/Ru and Cu/Ru complexes [(WCA‐NHC)M(μ‐X)2Ru(PPh3)(η6‐p‐cymene)] (M=Ag, Cu, X=Cl; M=Ag, X=I). Surprisingly, these complexes resisted the elimination of CuCl, AgCl, or AgI, precluding WCA‐NHC transmetalation.
Homarine Alkyl Ester Derivatives as Promising Acetylcholinesterase Inhibitors
Authors: João Karen G. , Videira Romeu A. , Paiva‐Martins Fátima , Valentão Patrícia , Pereira David M. , Andrade Paula B. 
Published: August 2021

AbstractReversible acetylcholinesterase (AChE) inhibitors are key therapeutic tools to modulate the cholinergic connectivity compromised in several degenerative pathologies. In this work, four alkyl esters of homarine were synthesized and screened by using Electrophorus electricus AChE and rat brain AChE‐rich fraction. Results showed that all homarine alkyl esters are able to inhibit AChE by a competitive inhibition mode. The effectiveness of AChE inhibition increases with the alkyl side chain length of the homarine esters, being HO−C16 (IC50=7.57±3.32 μM and Ki=18.96±2.28 μM) the most potent inhibitor. The fluorescence quenching studies confirmed that HO−C16 is the compound with higher selectivity and affinity for the tryptophan residues in the catalytic active site of AChE. Preliminary cell viability studies showed that homarine esters display no toxicity for human neuronal SH‐SY5Y cells. Thus, the long‐chain homarine esters emerge as new anti‐cholinesterase agents, with potential to be considered for therapeutic applications development.
Structural Design of Composite Polymer Electrolytes for Solid‐state Lithium Metal Batteries
Authors: Liao Wenchao , Liu Chen 
Published: August 2021

AbstractComposite polymer electrolytes with good safety and improved electrochemical performance have attracted widespread attention. However, the ion conduction ability at room temperature and interface compatibility between the electrolyte and electrode still face huge challenges, which greatly hinders the overall performance of solid‐state batteries. Therefore, the focus of this review is on the impact of the composite electrolyte structure on its ion conduction ability and interfacial compatibility, including physical contact of the electrolyte with electrodes, formation of lithium dendrites and space charge layer, adapting to high‐voltage cathode, as well as corresponding solving strategies. Moreover, the structural design‐based ion transport mechanism is highlighted, and the inorganic component with 0D, 1D, 2D, 3D and vertical structure are summarized. The purpose here is to outline the problems and challenges in structural design of composite electrolytes and their interfacial compatibility with various electrodes, allowing for target‐oriented research for high performance solid‐state lithium metal batteries.
An inertial Douglas–Rachford splitting algorithm for nonconvex and nonsmooth problems
Authors: Feng Junkai , Zhang Haibin , Zhang Kaili , Zhao Pengfei 
Published: August 2021

SummaryIn the fields of wireless communication and data processing, there are varieties of mathematical optimization problems, especially nonconvex and nonsmooth problems. For these problems, one of the biggest difficulties is how to improve the speed of solution. To this end, here we mainly focused on a minimization optimization model that is nonconvex and nonsmooth. Firstly, an inertial Douglas–Rachford splitting (IDRS) algorithm was established, which incorporate the inertial technology into the framework of the Douglas–Rachford splitting algorithm. Then, we illustrated the iteration sequence generated by the proposed IDRS algorithm converges to a stationary point of the nonconvex nonsmooth optimization problem with the aid of the Kurdyka–Łojasiewicz property. Finally, a series of numerical experiments were carried out to prove the effectiveness of our proposed algorithm from the perspective of signal recovery. The results are implicit that the proposed IDRS algorithm outperforms another algorithm.
Sunn hemp planting date effect on growth, biomass accumulation, and nutritive value in southeastern Wyoming
Authors: Eberle Carrie , Shortnacy Lauren 
Published: August 2021

AbstractSustainablesuccess of the Northern High Plains (NHP) crop and livestock industry is limited by market accessibility, infertile soils, short growing seasons, and availability of high nutritive value, low‐cost feed. Adoption of the tropical legume, Crotalaria juncea L. (commonly known as sunn hemp), into NHP cropping systems could improve the sustainability of the rotation by fitting into summer growing windows and being used as a hay alternative. Rainfed and irrigated studies were conducted in Lingle, WY, to determine the target planting date for sunn hemp in the NHP. Later planting day of year was correlated with increased percent establishment in the rainfed study but had no effect in the irrigated study. In both irrigated and rainfed studies, planting between 8 June and 18 June maximized biomass accumulation. Biomass accumulation 60 d after planting ranged from 0.2 to 5.1 Mg ha–1 in the rainfed study and 1.2 to 4.2 Mg ha–1 in the irrigated study. For both irrigated and rainfed studies, the nutritive value of sunn hemp was high with crude protein greater than 220 g Kg–1, acid detergent fiber less than 305 g Kg–1, neutral detergent fiber less than 331 g Kg–1, relative feed values above 183, and total digestible nutrients greater than 590 g Kg–1. Planting date did not affect nutritive value. Sunn hemp grown in the NHP has a 60‐d yield potential 5.1 Mg ha–1, should be planted between 8–18 June to 60‐d biomass production, and has nutritive value equivalent to supreme quality alfalfa (Medicago sativa L.) hay.