bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding Correlation Between CO2 Insertion Mechanism and Chain Length of Diamine in Metal‐Organic Framework Adsorbents
Authors: Ju Susan E. , Choe Jong Hyeak , Kang Minjung , Kang Dong Won , Kim Hyojin , Lee Jung‐Hoon , Hong Chang Seop 
Published: April 2021

AbstractAlthough CO2 insertion is a predominant phenomenon in diamine‐functionalized Mg2(dobpdc) (dobpdc4−=4,4‐dioxidobiphenyl‐3,3′‐dicarboxylate) adsorbents, a high‐performance metal‐organic framework for capturing CO2, the fundamental function of the diamine carbon chain length in the mechanism remains unclear. Here, Mg2(dobpdc) systems with open metal sites grafted by primary diamines NH2−(CH2)n−NH2 were developed, with en (n=2), pn (n=3), bn (n=4), pen (n=5), hn (n=6), and on (n=8). Based on CO2 adsorption and IR results, CO2 insertion is involved in frameworks with n=2 and 3 but not in systems with n≥5. According to NMR data, bn‐appended Mg2(dobpdc) exhibited three different chemical environments of carbamate units, attributed to different relative conformations of carbon chains upon CO2 insertion, as validated by first‐principles density functional theory (DFT) calculations. For 1‐hn and 1‐on, DFT calculations indicated that diamine inter‐coordinated open metal sites in adjacent chains bridged by carboxylates and phenoxides of dobpdc4−. Computed CO2 binding enthalpies for CO2 insertion (−27.8 kJ mol−1 for 1‐hn and −20.2 kJ mol−1 for 1‐on) were comparable to those for CO2 physisorption (−19.3 kJ mol−1 for 1‐hn and −20.8 kJ mol−1 for 1‐on). This suggests that CO2 insertion is likely to compete with CO2 physisorption on diamines of the framework when n≥5.
Reuse of LiCoO2 Electrodes Collected from Spent Li‐Ion Batteries after Electrochemical Re‐Lithiation of the Electrode
Authors: Lahtinen Katja , Rautama Eeva‐Leena , Jiang Hua , Räsänen Samuli , Kallio Tanja 
Published: April 2021

AbstractThe recycling of used Li‐ion batteries is important as the consumption of batteries is increasing every year. However, the recycling of electrode materials is tedious and energy intensive with current methods, and part of the material is lost in the process. In this study, an alternative recycling method is presented to minimize the number of steps needed in the positive electrode recovery process. The electrochemical performance of aged and re‐lithiated Mg−Ti‐doped LiCoO2 and stoichiometric LiCoO2 was investigated and compared. The results showed that after re‐lithiation the structure of original LiCoO2 was restored, the capacity of an aged LiCoO2 reverted close to the capacity of a fresh LiCoO2, and the material could thus be recovered. The re‐lithiated Mg−Ti‐doped LiCoO2 provided rate capability properties only slightly declined from the rate capability of a fresh material and showed promising cyclability in half‐cells.
Chirripó hydrological research site: Advancing stable isotope hydrology in the Central American Páramo
Authors: Esquivel‐Hernández Germain , Sánchez‐Murillo Ricardo , Vargas‐Salazar Enzo 
Published: April 2021

AbstractThe Chirripó hydrological research site (CHRS) is located within the Chirripó National Park, Costa Rica (between 3100 and 3820 m asl) whereby ~100 km2 are covered by Páramo, a high‐elevation tropical grassland ecosystem. A lake district with approximately 30 lakes of glacial origin is also protected in this area. The CHRS has been monitored since April 2015 with the aim of establishing the first water isotope baseline for the Central American Páramo. At a regional scale, the water isotope ratios (δ2H and δ18O) in precipitation and surface water at CHRS are useful for describing the governing moisture transport from the Caribbean Sea and Pacific Ocean and the complex rainfall producing systems across the N–S mountain range of Central America. These data are also providing unique information about the evaporation and water balance conditions of tropical glacial lakes and the formation of orographic and convective precipitation in high‐elevation tropical ecosystems. Current data sets from CHRS include continuous lake water temperature and meteorological conditions (i.e., precipitation amount, air temperature and relative humidity), as well as water stable isotopes in precipitation, stream water, and lake water (daily to biweekly sampling frequency). Stream water is collected at several locations across the topographic gradient whereas lake water is sampled in the three main lake systems of CHRS. CHRS serves as a reference site for conducting pilot isotopic research in high‐elevation ecosystems to advance the atmospheric, hydrogeological and ecohydrological studies in these understudied biomes. All data from April 2015 to November 2020 are publicly available.
An end‐to‐end brain tumor segmentation system using multi‐inception‐UNET
Authors: Latif Urva , Shahid Ahmad R. , Raza Basit , Ziauddin Sheikh , Khan Muazzam A. 
Published: April 2021

AbstractAccurate detection and pixel‐wise classification of brain tumors in Magnetic Resonance Imaging (MRI) scans are vital for their diagnosis, prognosis study and treatment planning. Manual segmentation of tumors from MRI is highly subjective and tedious. With recent advances in deep learning, automatic brain tumor segmentation is an emerging research direction in the medical imaging domain. We present a study to improve the automatic segmentation process by introducing size variability in the Convolutional Neural Network (CNN). For pixel‐wise classification of tumorous slices convolutional neural network‐based encoder‐decoder UNET model is referred. A multi‐inception‐UNET model is proposed to improve scalability of the UNET model. Extensive experiments have been performed using the Brain Tumor Segmentation Challenge (BRATS) datasets to establish the validity of our proposed model. Experimental results show that our proposed method achieved the best results on BraTS 2015, 2017 and 2019 datasets for complete tumor, core tumor and enhancing tumor regions respectively.
In silico identification of prolyl hydroxylase inhibitor by per‐residue energy decomposition‐based pharmacophore approach
Authors: Teli Mahesh Kumar , Kumar Surendra , Yadav Dharmendra Kumar , Kim Mi‐hyun 
Published: April 2021

AbstractHypoxia is an effective preconditioning stimulus and many cellular responses to hypoxia are mediated through a transcription control complex termed the hypoxia‐inducible factor (HIF). The stability and activation of HIF are governed by HIF prolyl‐4‐hydroxylases 2 (PHD2). Hence, the development of a small molecule inhibitor for prolyl hydroxylase has been suggested as a potentially useful therapeutic strategy for the treatment of oxidative/ischemic stress conditions. Thus, to unveil a novel human PHD2 inhibitor, a custom‐based virtual screening was carried out to identify the potential inhibitors against PHD2 based on; (1) the per‐residue energy decomposition (PRED)‐based pharmacophore model, (2) molecular docking, and (3) MD approaches. The PRED analysis was performed to identify the common interaction pattern of HIF fragment (5L9B) and crystallized ligand (4JZR) to develop a relevant accurate allosteric pharmacophore model. The custom pharmacophore model (AAARR) was developed and further used to screen multiple databases. The docking was performed as a secondary strategy for screening the pharmacophore hits. Furthermore, the docked complexes were screened by molecular dynamics (MD) simulation and molecular mechanics/generalized Born surface area (MM–GBSA) based binding free energy calculations to determine the binding energy of the inhibitors and to identify crucial interaction energy fingerprint. One hit has demonstrated good binding free energy and a better binding affinity for PHD2 compared to the other four selected ligands. Thus, the results obtained from pharmacophore, docking, and MD simulations depicted that linker length and metal binding in the scaffold could be effectively used as a potent inhibitor toward human PHD2 in AD therapeutics.
Modeling ligand electrochemical parameters by repulsion‐corrected eigenvalues
Authors: Kiani Pirouz , Dodsworth Elaine S. , Lever A. B. P. , Pietro William J. 
Published: April 2021

AbstractLigand electrochemical parameters, EL, more commonly known as Lever parameters, have played a major research role in understanding redox processes involved in inorganic electrochemistry, enzymatic reactions, catalysis, solar cells, biochemistry, and materials science. Despite their broad usefulness, Lever parameters are not well understood at a first‐principles level. Using density functional theory, we demonstrate in this contribution that a ligand's Lever parameter is fundamentally related to the ligand's ability to alter the eigenvalue of the electroactive spin‐orbital in an octahedral transition metal complex. Our analysis furthers a first‐principles understanding of the nature of Lever parameters.
Post‐9/11 military veterans' adjustment to civilian life over time following separation from service
Authors: Park Crystal L. , Sacco Shane J. , Finkelstein‐Fox Lucy , Sinnott Sinead M. , Scoglio Arielle A. J. , Lee Sharon Y. , Gnall Katherine E. , Mazure Carolyn , Shirk Steven D. , Hoff Rani A. , Kraus Shane W. 
Published: April 2021

AbstractObjectivesUS military veterans face many challenges in transitioning to civilian life; little information is available regarding veterans' reintegration experiences over time. The current study characterized veterans' postdeployment stressful life events and concurrent psychosocial wellbeing over one year and determined how stressors and wellbeing differ by demographic factors.MethodsRecent Post‐911 veterans (n = 402) were assessed approximately every three months for 1 year. Participants were 60% men, primarily White (78%), and 12% Latinx; the average age was 36 years.ResultsThe frequency of stressful events decreased over time but was higher for men and minority‐race veterans (independent of time since separation). Veterans reported high mean levels of posttraumatic stress disorder, anxiety, and insomnia symptoms, which improved slightly over time. Minority‐race and Latinx veterans had higher symptom levels and slower rates of symptom reduction.ConclusionVeterans remain distressed in their overall transition to civilian life. Interventions to promote resilience and help veterans manage readjustment to civilian life appear urgently needed.
Barriers and opportunities for dental school faculty research
Authors: Chambers David W. , Brady Michelle 
Published: April 2021

AbstractPurpose/objectivesIdentify barriers and opportunities regarding faculty participation in research.MethodsSixty‐four faculty members of all ranks and days of employment completed a survey designed to reveal attitudes toward participation in research.ResultsAmong those responding, three‐quarters said they were actively engaged in research, and 45% of these identified no perceived barriers. Those reporting obstacles rank‐ordered 10 barriers, but no consistent patterns emerged. A factor analysis revealed three clusters of concerns: (a) school barriers, (b) personal barriers, and (c) team opportunities. A large number of comments were offered, and these tended to group by the three quantitatively identified factors.ConclusionThese findings were consistent with the view that lack of time and formal training in standardized research skills were not major impediments to scholarship. Instead, assistance in navigating administrative hurdles and participation on multiskilled teams appeared to offer the best prospect for helping faculty interested in research.
Antimicrobial effects of vanillin‐based pyridyl‐benzylidene‐5‐fluoroindolins
Authors: Raymond Mohanraj Deena Gladies , Alagumuthu Manikandan , Subramaniam Palaniraja , Bakthavachalam Dhivya , Arumugam Sivakumar , Chellam Subha 
Published: April 2021

AbstractIn this study, the antimicrobial effect and DNA gyrase inhibitor potential of vanillin‐based pyridyl–substituted fluoro‐indolines were evaluated. These compounds are synthesized and established through green‐chemistry approaches. The inhibition effect on both DNA gyrase A and B was evaluated in silico and in vitro. Agar well diffusion method–based antimicrobial activity against Gram‐ve Pseudomonas aeruginosa (MTCC 424) and Escherichia coli (MTCC 443), Gram+ve Streptococcus pyogenes (MTCC 442) and Staphylococcus aureus (MTCC 96), and a clinical isolate of Candida albicans (Fungi) was evaluated. The cytotoxicity of the compounds was assessed over macrophages using the MTT assay. In the results, the target compounds exhibited a broad‐spectrum antimicrobial activity against both bacterial types and fungal.
On the protonation and deuteration of N,N‐disubstituted 2‐aminothiophenes, 2‐aminothiazoles, and some 3‐amino substituted analogues
Authors: Heichert Christoph , Hartmann Horst 
Published: April 2021

AbstractIn contrast to their carbocyclic aniline analogues, N,N‐diarylsubtituted 2‐aminothiophenes are not protonated at their N‐atoms but at the 5‐position or, to a smaller extent, at the 3‐position of the thiophene nucleus giving rise to cationic species of the Wheland type. However, 5‐formyl and 5‐acetyl‐substituted 2‐(N,N‐diarylamino)thiophenes are protonated at the corresponding carbonyl moieties. This finding not only enables insight into the mechanism of electrophilic substitution of N,N‐disubstituted 2‐aminothiophenes but also allows to prepare deurated 2‐aminothiophenes by treatment their non‐deuterated parent compounds with CF3COOD.
A semiautomated method to quantitatively assess osteolytic lesion volume and bone mineral density within acetabular regions of interest from CT
Authors: Grace Thomas M. , O'Rourke Dermot , Robertson Thomas , Perilli Egon , Callary Stuart , Taylor Mark , Atkins Gerald J. , Solomon Lucian B. , Thewlis Dominic 
Published: April 2021

AbstractThe objectives of this study were to (1) develop a semiautomated method to obtain lesion volume and bone mineral density (BMD) in terms of Hounsfield units from pelvic computed tomography (CT) scans in three regions of interest, and (2) assess accuracy and reliability of the method based on cadaveric CT scans. Image artefacts due to metal implants reduce CT clarity and are more severe with more than one implant in situ. Therefore, accuracy and reliability tests were performed with varying numbers of total hip arthroplasties implanted. To test the accuracy of lesion size measurements, microcomputed tomography was used as a reference. Mean absolute error ranged from 36 to 284 mm3 after five measurements. Intra‐ and inter‐operator reliability of the entire method was measured for a selection of parameters. All coefficient of variation values were good to excellent for CT scans of the native pelvic anatomy and a CT scans of the same pelvis with one and two implants in situ. Accuracy of quantifying lesion volume decreased with decreasing CT image clarity by 0.6%–3.6% mean absolute relative error. Reliability of lesion volume measurement decreased with decreasing CT clarity. This was also the case for reliability of BMD measurements in the region most disrupted by metal artefact. The presented method proposes an approach for quantifying bone loss which has been proven to be accurate, reliable, and clinically applicable.
Imparting Gradient and Oriented Characters to Cocontinuous Structure for Improving Integrated Performance
Authors: Sun Zhao‐Bo , Song Ying‐Nan , Ma Guo‐Qi , Gao Ping‐Ping , Xie Ze‐Xiang , Gao Xue‐Qin , Li Yue , Xu Jia‐Zhuang , Zhong Gan‐Ji , Li Zhong‐Ming 
Published: April 2021

AbstractInspired by the oriented, gradient, and heterogeneous characters of natural materials, an oriented and gradient cocontinuous structure is designed to obtain excellent mechanical performance via a gradient shear stress and temperature during melt processing. The investigation of hierarchical structure containing phase morphology, crystalline morphology, and lamellae in the cocontinuous structure can clarify the role of gradient shear stress and temperature in promoting gradient and oriented features. Given such oriented and gradient features in the cocontinuous structure, a notable enhancement in the tensile strength, tensile modulus, elongation at break, and impact strength is achieved in the model poly(butylene adipate‐ran‐terephthalate)/poly(butylene succinate) biodegradable cocontinuous blends. Compared with the isotropic cocontinuous structure, homogenous structure and discrete phase structure, oriented and gradient cocontinuous structure provides a promising balance of strength, hardness, and toughness. Local reinforcement is achieved by highly oriented cocontinuous phase, crystal, and lamellae in skin layer. Meanwhile, the toughness is achieved by weakly oriented cocontinuous phase. The tuning of cocontinuous structure with gradient and oriented features is suggested as a new pathway toward the development of “materials systems” with unprecedented mechanical performance.
Multicomponent topology optimization of functionally graded lattice structures with bulk solid interfaces
Authors: Yi Bing , Saitou Kazuhiro 
Published: April 2021

AbstractThis article presents a topology optimization method for structures consisting of multiple lattice components under a certain size, which can be manufactured with an additive manufacturing machine with a size limit and assembled via conventional joining processes, such as welding, gluing, riveting, and bolting. The proposed method can simultaneously optimize overall structural topology, partitioning to multiple components and functionally graded lattices within each component. The functionally graded lattice infill with guaranteed connectivity is realized by applying the Helmholtz PDE filter with a variable radius on the density field in the solid isotropic material with penalization (SIMP) method. The partitioning of an overall structure into multiple components is realized by applying the discrete material optimization (DMO) method, in which each material is interpreted as each component, and the size limit for each component imposed by a chosen additive manufacturing machine. A gradient‐free coating filter realizes bulk solid boundaries for each component, which provide continuous mating surfaces between adjacent components to enable the subsequent joining. The structural interfaces between the bulk solid boundaries are extracted and assigned a distinct material property, which model the joints between the adjacent components. Several numeral examples are solved for demonstration.
Shwachman‐Diamond syndrome and solid tumors: Three new patients from the French Registry for Severe Chronic Neutropenia and literature review
Authors: Bou Mitri Fares , Beaupain Blandine , Flejou Jean‐François , Patient Matthieu , Okhremchuck Ilona , Blaise Didier , Izadifar‐Legrand Faézeh , Martignoles Jean Alain , Delhommeau François , Bellanne‐Chantelot Christine , Emile Jean‐François , Donadieu Jean 
Published: April 2021

AbstractShwachman‐Diamond syndrome with Shwachman‐Bodian‐Diamond syndrome (SBDS) biallelic variants is a rare disorder that predisposes the carrier to malignant hemopathies but solid‐cancer predisposition is poorly known. Among 155 cases entered in the French Registry for Severe Chronic Neutropenia, three were identified with malignant solid tumors (ovary, breast, and esophagus). All cancers occurred during the fifth decade and, despite being localized at diagnosis, were rapidly fatal thereafter. No cancer was observed post transplantation in the 14 HSCT survivors. Based on the literature and our patient data, we can merely advance that this complication is predominantly diagnosed in adults.
Role of nano‐zirconia in the mechanical properties improvement of resin cement used for tooth fragment reattachment
Authors: El‐Kemary Baraa M. , El‐Borady Ola M. , Abdel Gaber Sara A. , Beltagy Talat M. 
Published: April 2021

AbstractDental fractures of the anterior teeth are a common form of dental trauma. Reattachment of fractured tooth fragment by means of self‐adhesive resin cement is currently compromised by the poor mechanical properties of these ceramics. Herein, we synthesized zirconium dioxide nanoparticles (nano‐ZrO2) using the Co‐precipitation approach and then mixing it in different concentrations (1.0, 2.0, 3.0, and 5.0 wt%) with the commercially available RelyX™ Unicem self‐adhesive universal resin cement (ARC) forming, nano‐ZrO2/ARC. Both the synthesized nano‐ZrO2 and nano‐ZrO2/ARC were characterized using a high‐resolution transmission electron microscope (HR‐TEM), field‐emission scanning electron microscope, X‐ray diffraction, and Fourier transform infrared technique. The HR‐TEM images revealed that the synthesized nano‐ZrO2 was spherical with a size of ~ 12 nm. The results showed that the addition of nano‐ZrO2 significantly enhanced the mechanical properties as fracture resistance, compressive strength, diametral tensile, and micro‐hardness values of the resin cement. The mixing 3.0 wt% of nano‐ZrO2 with ARC revealed the maximum improvement in the mechanical properties and, consequently, the resin's repair strength. Their incorporation with ARC up to 3.0% wt did not cause significant cell death than ARC alone. We believe that the information discussed here might be relevant to the stability of nano‐ZrO2‐modified resin cement and, therefore, to its clinical usage for fragment tooth reattachment, cementation of dental crowns, bridges, and bands.
Malevolent object relations: A multimethod study of female survivors of childhood abuse
Authors: Adams Brett E. , Porcerelli John H. , Abell Steven , Huprich Steven K. 
Published: April 2021

AbstractAlthough childhood victimization is associated with impairments in object relations, it is not clear how different measures comparatively perform in assessing this relationship. This study examined the connection between emotional, physical, and sexual abuse in childhood and three methods of assessing malevolent object representations. Sixty adult women, recruited from an urban primary‐care clinic, were administered the Thematic Apperception Test (TAT), the Object Relations Inventory (ORI) interview, and a version of the Early Memories Test (EMT)/interview. Ratings of malevolent object relations were obtained using the affect‐tone dimension from the Social Cognition and Object Relations (SCORS‐G) scale with both TAT and early memory narratives and through Malevolence ratings from the ORI interview. It was found that, outside of emotional abuse, ORI interview ratings of malevolence consistently differentiated adult childhood abuse groups and nonabuse groups, whereas early memory ratings of malevolence differentiated groups in two of four analyses. Malevolence ratings based upon TAT ratings failed to differentiate any type of abuse from nonabuse. These findings suggest that the use of malevolence ratings from the ORI and early memory narratives are preferred methods for assessing malevolent object relations in urban‐dwelling women who have been victimized as children.