bluuebunny/crossref_metadata_2025_split huggingface dataset:
Boosting Surface Reconstruction for the Oxygen Evolution Reaction: A Combined Effect of Heteroatom Incorporation and Anion Etching in Cobalt Silicate Precatalyst
Authors: Sarkar Debashrita , Ganguli Sagar , Mondal Ayan , Mahalingam Venkataramanan 
Published: November 2021

AbstractElectrochemical water splitting is one of the most desirable techniques for combatting the global challenge of sustainable fuel generation. The generation of highly active electrocatalysts for efficient oxygen evolution reaction (OER) requires the rational design of a precatalyst that can enhance the number density of the active catalyst generated during water splitting. In this work, we report sulfurincorporated iron‐doped cobalt silicate (CoFeSiO−S) nanoparticles, which exhibit a unique ability to show gradual improvement in the electrocatalytic behavior with time. The precatalyst could reach a low overpotential of 267±6 mV at benchmark current density of 10 mA/cm2 and 300 mV at 100 mA/cm2 current density after applying chronopotentiometry for 30 h. The exceptional OER performance is further evidence by a low Tafel slope of 37.0±0.5 mV/dec with a very high TOF value of 1.05 s−1. This improved activity is attributed to 1) facilitation of Co2+/Co3+ by Fe doping, 2) faster catalyst activation due to lower metal‐sulfur bond energy compared to metal‐oxygen bond energy, 3) higher pore diameter that enables faster diffusion of reactants and products, 4) lower charge transfer resistance of sulfur incorporated iron‐doped cobalt phyllosilicate than pristine, and 5) silicate anion etching in the electrolyte. This work establishes a fundamental understanding of the surface reconstruction occurring during the OER process where silicates are employed as precatalyst.
In Situ Activation/Dedoping‐Induced Defective Carbon Sponge for Enhanced Oxygen Reduction Electrocatalysis
Authors: Wei Keyan , Zheng Hongmei , Hou Jingting , Tang Zeming , Zheng Jing , Lai Qingxue , Liang Yanyu 
Published: November 2021

AbstractThe N‐dedoping‐based defect engineering strategy has been designed as an efficient method to develop advanced defective carbon electrocatalysts for the oxygen reduction reaction (ORR). However, the defective structures, especially the defect density of carbon materials fabricated by this method, were significantly suppressed by the limited N doping level. Herein, an in situ activation/N‐dedoping strategy was proposed to fabricate a controllable defective carbon sponge (DCS) for ORR electrocatalysts, during which a Schiff‐base polymer with a high N content was employed as the carbon precursor and N source while zinc oxide (ZnO) nanoparticles were the thermally removable structure template and activator. As a result, the optimized DCS1100 with a high specific surface area of 1198 m2/g and a low nitrogen content of 2.81 at.% delivered a comparable activity and four‐electron selectivity but superior stability to commercial 30 % Pt/C in 0.1 M KOH electrolyte.
DEB‐FAPy‐dG Adducts of 1,3‐Butadiene: Synthesis, Structural Characterization, and Formation in 1,2,3,4‐Diepoxybutane Treated DNA**
Authors: Pujari Suresh S. , Jokipii Krueger Caitlin C. , Chao Christopher , Hutchins Spencer , Hurben Alexander K. , Boysen Gunnar , Tretyakova Natalia 
Published: November 2021

AbstractMetabolic activation of the human carcinogen 1,3‐butadiene (BD) by cytochrome 450 monooxygenases gives rise to a genotoxic diepoxide, 1,2,3,4‐diepoxybutane (DEB). This reactive electrophile alkylates guanine bases in DNA to produce N7‐(2‐hydroxy‐3,4‐epoxy‐1‐yl)‐dG (N7‐DE‐dG) adducts. Because of the positive charge at the N7 position of the purine heterocycle, N7‐DEB‐dG adducts are inherently unstable and can undergo spontaneous depurination or base‐catalyzed imidazole ring opening to give N6‐[2‐deoxy‐D‐erythro‐pentofuranosyl]‐2,6‐diamino‐3,4‐dihydro‐4‐oxo‐5‐N‐1‐(oxiran‐2‐yl)propan‐1‐ol‐formamidopyrimidine (DEB‐FAPy‐dG) adducts. Here we report the first synthesis and structural characterization of DEB‐FAPy‐dG adducts. Authentic standards of DEB‐FAPy‐dG and its 15N3‐labeled analogue were used for the development of a quantitative nanoLC‐ESI+‐HRMS/MS method, allowing for adduct detection in DEB‐treated calf thymus DNA. DEB‐FAPy‐dG formation in DNA was dependent on DEB concentration and pH, with higher numbers observed under alkaline conditions.
Developing Efficient Small Molecule Acceptors with sp2‐Hybridized Nitrogen at Different Positions by Density Functional Theory Calculations, Molecular Dynamics Simulations and Machine Learning
Authors: Mahmood Asif , Irfan Ahmad , Wang Jin‐Liang 
Published: November 2021

AbstractChemical structure of small molecule acceptors determines their performance in organic solar cells. Multiscale simulations are necessary to avoid trial‐and‐error based design, ultimately to save time and resources. In current study, the effect of sp2‐hybridized nitrogen substitution at the inner or the outmost position of central core, side chain, and terminal group of small molecule acceptors is investigated using multiscale computational modelling. Quantum chemical analysis is used to study the electronic behavior. Nitrogen substitution at end‐capping has significantly decreased the electron‐reorganization energy. No big change is observed in transfer integral and excited state behavior. However, nitrogen substitution at terminal group position is good way to improve electron‐mobility. Power conversion efficiency (PCE) of newly designed acceptors is predicted using machine learning. Molecular dynamics simulations are also performed to explore the dynamics of acceptor and their blends with PBDB‐T polymer donor. Florgy‐Huggins parameter is calculated to study the mixing of designed small molecule acceptors with PBDB‐T. Radial distribution function has indicated that PBDB‐T has a closer packing with N3 and N4. From all analysis, it is found that nitrogen substitution at end‐capping group is a better strategy to design efficient small molecule acceptors.
Resilient health care in global pediatric oncology during the COVID‐19 pandemic
Authors: Graetz Dylan E. , Sniderman Elizabeth , Villegas Cesar A. , Kaye Erica C. , Ragab Iman , Laptsevich Aliaksandra , Maliti Biemba , Naidu Gita , Huang Haiying , Gassant Pascale Y. , Nunes Silva Luciana , Arce Daniela , Montoya Vasquez Jacqueline , Arora Ramandeep Singh , Alcasabas Ana Patricia , Rusmawatiningtyas Desy , Raza Muhammad Rafie , Velasco Pablo , Kambugu Joyce , Vinitsky Anna , Rodriguez‐Galindo Carlos , Agulnik Asya , Moreira Daniel C. ,   for the COVIMPACT Study Group
Published: November 2021

BackgroundIn the face of unprecedented challenges because of coronavirus disease 2019, interdisciplinary pediatric oncology teams have developed strategies to continue providing high‐quality cancer care. This study explored factors contributing to health care resilience as perceived by childhood cancer providers in all resource level settings.MethodsThis qualitative study consisted of 19 focus groups conducted in 16 countries in 8 languages. Seven factors have been previously defined as important for resilient health care including: 1) in situ practical experience, 2) system design, 3) exposure to diverse views on the patient's situation, 4) protocols and checklists, 5) teamwork, 6) workarounds, and 7) trade‐offs. Rapid turn‐around analysis focused on these factors.ResultsAll factors of health care resilience were relevant to groups representing all resource settings. Focus group participants emphasized the importance of teamwork and a flexible and coordinated approach to care. Participants described collaboration within and among institutions, as well as partnerships with governmental, private, and nonprofit organizations. Hierarchies were advantageous to decision‐making and information dissemination. Clinicians were inspired by their patients and explained creative trade‐offs and workarounds used to maintain high‐quality care.ConclusionsFactors previously described as contributing to resilient health care manifested differently in each institution but were described in all resource settings. These insights can guide pediatric oncology teams worldwide as they provide cancer care during the next phases of the pandemic. Understanding these elements of resilience will also help providers respond to inevitable future stressors on health care systems.
The number of brain metastases predicts the survival of non‐small cell lung cancer patients with EGFR mutation status
Authors: Shao Jun , Li Jingwei , Song Lujia , He Qiuyao , Wu Yuxuan , Li Linhui , Liu Dan , Wang Chengdi , Li Weimin 
Published: November 2021

AbstractBackgroundLung cancer is the common cause of cancer‐related deaths throughout the world, and brain is a frequent metastatic site of lung cancer.AimThis research sought to evaluate the impact of the number of brain metastases in prognosticating non‐small cell lung cancer (NSCLC) patients accounting to the role of epidermal growth factor receptor (EGFR) mutations.Methods and ResultsNSCLC patients with brain metastases diagnosed/treated in West China Hospital, Sichuan University between 2009 and 2017 were identified retrospectively. Kaplan–Meier approach was adopted to estimate OS. And we performed univariate and multivariate Cox proportional hazards regression analyses of characteristics related to overall survival (OS) in both EGFR‐mutated and wild‐type cohorts. In total, this study included 611 eligible NSCLC patients with brain metastases. Extracranial metastases and chemotherapy were independent prognostic factors of OS in both cohorts. As the disease progressed, EGFR‐mutated patients had brain metastasis significantly earlier (P < .0001), but they also had notably better survival outcomes than wild‐type patients (P < .0001). And the number of brain metastases impacted the survival incidence in the progression significantly in both EGFR‐mutated and wild‐type groups (P = .0087/.037, respectively).ConclusionThe number of brain metastases was a prognostic factor for lung cancer patients either with EGFR mutations or with wild‐type EGFR, with larger number indicating more unfavorble clinical outcomes. Patients with EGFR mutations had a better survival.
Pleomorphic dermal sarcoma: Clinicopathological features and outcomes from a 5‐year tertiary referral centre experience
Authors: Logan Ian T. , Vroobel Katherine M. , le Grange Franel , Perrett Conal M. 
Published: November 2021

AbstractBackgroundPleomorphic dermal sarcoma (PDS) describes rare dermal‐based malignant tumours that are morphologically similar to atypical fibroxanthoma (AFX). PDS may be differentiated from AFX by the presence of one or more of the following histologic features: subcutaneous invasion, tumour necrosis, lymphovascular invasion (LVI), and/or perineural infiltration (PNI).AimsTo further define the clinicopathological features, surgical management, and outcomes of PDS primary tumours.Methods and ResultsThis study was a retrospective observational case series using a database search from 2012 to 2017. Inclusion criteria required all cases to meet the histopathologic criteria for PDS as confirmed by a specialist soft‐tissue histopathologist. A total of n = 17 cases were included with a median age of 78 years (range 66–85). All tumours were located on the head and neck, with 13/17 located on the scalp. Primary treatment was with wide local excision (WLE) in all cases. Median follow‐up was 48 months. Local recurrence occurred in 4/17 cases (24%) and distant metastasis in 2/17 cases (12%).ConclusionPDS behaves more aggressively than atypical fibroxanthoma with which it shares a biologic continuum. The optimal surgical management approach is yet to be determined.
Enhanced global and local face feature extraction for effective recognition of facial emotions
Authors: Retnamony Jeen Retna Kumar , Muniasamy Sundaram , Stanley Berakhah Florence 
Published: November 2021

AbstractEmotion recognition is a challenging task in the field of human computer interaction. For a successful human emotion recognition system, a robust, discriminative, and sensitive feature extraction is an essential need. In this article, the extraction of global features is done by the proposed frequency decoded lifting wavelet pattern descriptor (FDLWP) and extraction of local features is done by the proposed local gradient difference zig‐zag pattern descriptor (LGDZP). The face parts are detected using viola jones algorithm and the selection of optimal face active regions is accomplished by the calculation of structural similarity index measure. Eventually the local spatial zig‐zag structure of the face region is utilized to attain LGDZP descriptor. The fusion of local and global features is accomplished using canonical correlation analysis. The classification made using bank of restricted Boltzmann machine (RBM) classifiers yields promising results for the proposed method. Furthermore, the proposed recognition method delivers a promising accuracy in varying illumination, occlusion, and noise. The accuracy of the method is analyzed by doing experiments with the databases such as JAFFE, CK+, MMI, Oulu‐CASIA, and SFEW. The obtained results of the proposed method yield better accuracy than the existing state of art methods in this field.
Mechanochemical Organocatalysis: Do High Enantioselectivities Contradict What We Might Expect?
Authors: Williams Matthew T. J. , Morrill Louis C. , Browne Duncan L. 
Published: November 2021

AbstractBall mills input energy to samples by pulverising the contents of the jar. Each impact on the sample or wall of the jar results in an instantaneous transmission of energy in the form of a temperature and pressure increase (volume reduction). Conversely, enantioselective organocatalytic reactions proceed through perceived delicate and well‐organised transition states. Does there exist a dichotomy in the idea of enantioselective mechanochemical organocatalysis? This Review provides a survey of the literature reporting the combination of organocatalytic reactions with mechanochemical ball milling conditions. Where possible, direct comparisons of stirred in solution, stirred neat and ball milled processes are drawn with a particular focus on control of stereoselectivity.
Symmetrical switching strategy based on reduced switching state in a three‐phase multilevel converter with a single faulty cell
Authors: Zolfagharian Omid , Dastfan Ali , Hoseintabar Marzebali Mohammad 
Published: November 2021

AbstractDue to the possibility of the occurrence of a fault in converters, performance improvement of a converter under faulty conditions is important. In this paper, for improving the performance of the three‐phase cascaded H‐bridge multilevel converters (CHB‐MLCs) with a single faulty cell, the quarter‐and half‐wave symmetry selective harmonic mitigation (SHM) modulation method as well as reducing the number of switching angles (NSA) has been used. Consequently, it helps to reduce the switching frequency (fs) and the number of sentences of the Fourier series thus simplifies the objective function. In addition, the proposed method enables the switching angles of a faulty cell to be transferred to other normal cells per phase. For this purpose, the switching angles of the cells are optimized so that at least one of the cells does not overlap with the other cells in the same phase. By employing the maximum modulation index under the faulty condition, the maximum capacities of the remaining DC sources are used and consequently, the line voltage drop in the output voltage is prevented. To produce a balanced line voltage, the fundamental phase‐shift Compensation (FPSC) method is employed. Simulation and experimental results are presented to confirm the efficiency of the proposed strategy.
Intelligent reflecting surface‐assisted downlink nonorthogonal multiple access systems
Authors: Sharma Sanjeev , Deka Kuntal , Dixit Dharmendra , A Rajesh 
Published: November 2021

SummaryRecently, intelligent reflecting surface (IRS)‐based communication systems are analyzed for 6G and beyond wireless networks. In this paper, we propose an IRS‐assisted downlink nonorthogonal multiple access (NOMA) system by considering separate IRS for near users (NUs) and far users (FUs). The optimal power allocation strategy among NUs and FUs is formulated for the proposed downlink IRS‐NOMA system. The symbol error probability and the sum‐rate performance of the IRS‐NOMA system are analyzed. Further, the impact of the modulation order, the number of reflecting surfaces, the number of phase shifts of reflected signals on symbol error, and power allocation between NU and FU is studied.
Advances in cocaine signature methodology: Alkaloid and isotope profiles of coca grown in Puno, Peru
Authors: Jones Laura M. , Ceniccola‐Campos Kristin E. , Morello David R. 
Published: November 2021

AbstractDrug Enforcement Administration's (DEA) Cocaine Signature Program previously identified 19 coca‐growing regions within South America and developed methodology to geo‐source cocaine using a combination of trace cocaine alkaloids, stable isotopes, and multivariate statistics. Twenty‐nine coca leaf samples collected in 2016 and 2019 from a previously unanalyzed coca‐growing region located in Puno, Peru, were analyzed with this methodology. Trace cocaine alkaloids and stable isotopes were compared with other Peruvian regions. Minor differences were observed in the extracted cocaine alkaloid profiles when compared with samples collected from the Ucayali‐Huallaga Valley and Cusco‐Apurimac regions while the stable isotopes of δ2H (−177.1‰) and δ18O (23.8‰) were enriched. Puno's alkaloid and stable isotope results are presented in this publication to assist forensic laboratories and enhance their cocaine geo‐sourcing capabilities.
Vitamin D status in children and adolescents with type 1 diabetes in a specialized diabetes care centre in Bangladesh
Authors: Zabeen Bedowra , Nahar Jebun , Ahmed Bulbul , Tayyeb Samin , Islam Nasreen , Azad Kishwar 
Published: November 2021

AbstractObjectivesHigh prevalence of vitamin D deficiency (VDD) in children and adolescents with type 1 diabetes (T1D) was found in several epidemiological studies. The current study aimed to assess the Vitamin D status in children and adolescents with T1D and to examine the influence of the disease characteristics on vitamin D status in a specialized care centre in a tertiary hospital in Bangladesh.MethodsParticipants were enrolled in the cross‐sectional study at the time of a regularly scheduled visit to the CDiC Paediatric Diabetes Center in BIRDEM 2(Bangladesh Institute of Research and Rehabilitation of Diabetes Endocrine and Metabolic Disorders), a tertiary care hospital in Bangladesh. The demographic and clinical data were collected through medical records with a structured questionnaire.ResultsAmong sixty study participants, most had inadequate levels of vitamin D: deficiency 31 (51.7%), insufficiency 14 (23.3%) and sufficiency 15 (25.0%). Participants with vitamin D deficiency (VDD) were significantly older compared to the sufficient and insufficient group (p = .029), and were residing in urban areas (p = .036) and from higher socioeconomic status (p = .014). BMI was significantly higher in VDD compared to the sufficient group (p = .040). Although we observed higher median values of daily insulin requirements and HbA1c values in patients with VDD compared to patients with vitamin D insufficiency or vitamin D sufficiency, these differences did not reach statistical significance.ConclusionsThe present study revealed that the prevalence of vitamin D deficiency and insufficiency among T1 diabetes children was very high. Future studies in large sample are required to assess hypovitaminosis D in youth with T1D and also the possible relating factors of vitamin D deficiency.
Stereoselective β‐Mannosylation via Anomeric O‐Alkylation with L‐Sugar‐Derived Electrophiles
Authors: Hettiarachchi Ishani Lakshika , Meng Shuai , Chahine Mira , Li Xiaohua , Zhu Jianglong 
Published: November 2021

AbstractA total synthesis of the trisaccharide repeat unit of Salmonella serogroup E1 O‐antigen is reported. This synthesis features a key β‐mannosylation reaction through a cesium carbonate‐mediated anomeric O‐alkylation of a partially protected D‐mannose with an L‐fucose‐derived electrophile for the first time.
Benzoannellated Fenestranes Bearing para‐Terphenyl Units
Authors: Seifert Monika , Barth Dieter , Kuck Dietmar 
Published: November 2021

AbstractThe synthesis of several centrotriindanes bearing ortho‐phenyl groups in the sterically constricted bay regions is described. The classical three‐step sequence including twofold cyclodehydration of the corresponding 2,2‐dibenzyl‐1,3‐indanediols afforded an angular difuso‐triidane and several all‐cis‐tribenzo[5.5.5.6]fenestranols equipped with two or four ortho‐phenyl groups. In contrast to the construction of these conformationally flexible centrotriindanes, attempts to synthesize ortho,ortho‐diphenyl‐substituted tribenzotriquinacenes failed due to the increased rigidity of the TBTQ skeleton. The high steric load imposed by the para‐terphenyl moieties affects the spirocyclization between 1,3‐indanedione and 1,5‐di‐(para‐2′‐terphenylyl)pentadienone, kinetic control of which is critical to access the all‐cis‐tribenzo[5.5.5.6]fenestrane framework. In contrast, the corresponding tetraphenyl‐cis,cis,cis,trans‐tribenzo[5.5.5.6]fenestranol is easily accessible.
Electrochemical 3D micro‐ and nanoprinting: Current state and future perspective
Authors: Hengsteler Julian , Lau Genevieve P. S. , Zambelli Tomaso , Momotenko Dmitry 
Published: November 2021

Abstract3D Printing in the micro‐ and nanoscale is a challenge extensively researched by the additive manufacturing community. Unlocking the third dimension adds an unprecedented degree of freedom for the fabrication of complex structures unavailable with conventional 2D microfabrication techniques. Electrochemical 3D printing methods provide sophisticated solutions tackling many of the problems arising when shrinking voxel sizes toward micro‐ or even nanometer scales, especially for the manufacturing of fine conductive (mostly metal) structures. Herein, we review the current state‐of‐the‐art methods of electrochemical additive manufacturing and discuss their perspective for future advances in terms of technology advancement in resolution and speed, materials, and applications for printing functional devices.