bluuebunny/crossref_metadata_2025_split huggingface dataset:
A duality‐based coupling of Cosserat crystal plasticity and phase field theories for modeling grain refinement
Authors: Baek Jonghyuk , Chen Jiun‐Shyan , Tupek Michael , Beckwith Frank , Fang H. Eliot 
Published: November 2021

AbstractHigh‐rate deformation processes of metals entail intense grain refinement and special attention needs to be paid to capture the evolution of microstructure. In this article, a new formulation for coupling Cosserat crystal plasticity and phase field is developed. A common approach is to penalize kinematic incompatibility between lattice orientation and displacement‐based elastic rotation. However, this can lead to significant solution sensitivity to the penalty parameter, resulting in low accuracy and convergence rates. To address these issues, a duality‐based formulation is developed which directly imposes the rotational kinematic compatibility. A weak inf‐sup‐based skew‐symmetric stress projection is introduced to suppress instabilities present in the dual formulation. An additional least squares stabilization is introduced to suppress the spurious lattice rotation with a suitable parameter range derived analytically and validated numerically. The required high‐order continuity is attained by the reproducing kernel approximation. It is observed that equal order displacement‐rotation‐phase field approximations are stable, which allows efficient employment of the same set of shape functions for all independent variables. The proposed formulation is shown to yield superior accuracy and convergence with marginal parameter sensitivity compared to the penalty‐based approach and successfully captures the dominant rotational recrystallization mechanism including block dislocation structures and grain boundary migration.
An efficient 4‐node facet shell element for the modified couple stress elasticity
Authors: Shang Yan , Wu Huan‐Pu , Cen Song , Li Chen‐Feng 
Published: November 2021

AbstractThis work proposes a simple but robust 4‐node 24‐DOF facet shell element for static analysis of small‐scale thin shell structures. To accommodate the size effects, the modified couple stress theory is employed as the theoretical basis. The element is constructed via two main innovations. First, the trial functions that can a priori satisfy related governing differential equations are adopted as the basic functions for formulating the element interpolations. Second, the generalized conforming theory and the penalty function method are employed to meet the C1 continuity requirement in weak sense for ensuring the computation convergence property. Several benchmarks of shells with different geometries are tested to assess the new facet shell element's capability. The numerical results reveal that the element can effectively simulate the size‐dependent mechanical behaviors of small‐scale thin shells, exhibiting satisfactory numerical accuracy and low susceptibility to mesh distortion. Moreover, as the shell element uses only six degrees of freedom per node, it can be incorporated into the commonly available finite element programs very readily.
Spectral Galerkin method for state constrained optimal control of fractional advection‐diffusion‐reaction equations
Authors: Wang Fangyuan , Zhou Zhaojie 
Published: November 2021

AbstractIn this article a spectral Galerkin approximation of fractional advection diffusion optimal control problem with state constraint in norm is discussed. The continuous first order optimality condition is derived. Weighted Jacobi polynomials are used to approximate the state and adjoint state. A priori error estimates for state, adjoint state, and control variables in and weighted norms are derived. Numerical examples are presented to verify the theoretical findings.
Long‐term weight loss maintenance with obesity pharmacotherapy: A retrospective cohort study
Authors: Tchang Beverly G. , Aras Mohini , Wu Alan , Aronne Louis J. , Shukla Alpana P. 
Published: November 2021

AbstractObjectiveTo determine the association of anti‐obesity medications (AOMs) with weight loss maintenance over 2 years.MethodsThis is a retrospective observational cohort study of adults treated for obesity between 1 April 2014 and 1 April 2016 at a tertiary academic weight management center and who completed 2 years of follow‐up. Main outcome measures were mean percent weight loss, percent of individuals who achieved clinically significant long‐term weight loss (≥5% weight loss over 2 years), and long‐term weight loss maintenance (achievement of ≥5% weight loss at 1 year and maintenance of the ≥5% reduction for the second year).ResultsOf the 1566 new patients, 421 completed 1‐ and 2‐year follow‐up appointments. Patients were mostly female and on average 51 years old; they weighed 100.1 kg and had a BMI of 35.8 kg/m2 at initial visit. Mean weight losses at 1 and 2 years were 10.1% and 10.2%, respectively. The proportion of patients who experienced ≥5% weight loss was 75.5% at 1 year and 72.9% at 2 years. Long‐term weight loss maintenance was achieved by 65.3% of patients. Almost all (96.2%) were on ≥1 AOM at 2 years, with metformin, phentermine, and topiramate among the most prescribed. AOM usage and older age demonstrated trends toward predicting weight loss maintenance over 2 years.ConclusionsLong‐term weight loss maintenance was observed among adults with medically managed obesity who completed 2 years of follow‐up.
Development of temperature‐responsive polymeric gels with physical crosslinking due to intermolecular 𝜋–𝜋 interactions
Authors: Shah Rishabh A , Runge Tyler , Ostertag Thomas W , Tang Shuo , Dziubla Thomas D , Hilt J Zach 
Published: November 2021

AbstractPoly(N‐isopropylacrylamide) was polymerized with comonomers containing a biphenyl moiety to create a unique thermoresponsive physically crosslinked system due to the presence of π–π interactions between the biphenyl moieties. The biphenyl monomers used were 2‐phenylphenol monoacrylate (2PPMA) and 4‐phenylphenol monoacrylate (4PPMA). These monomers were utilized to synthesize a set of polymers with biphenyl monomer (2PPMA/4PPMA) content from 2.5 to 7.5 mol% and with initiator concentrations of 0.1 and 1.0 wt%. The resulting polymers were characterized using various techniques, such as gel permeation chromatography (GPC), swelling studies and mechanical testing. A decrease in the average molecular weight of the polymers due to the increase in the concentration of initiator was confirmed from GPC results. Swelling studies confirmed the expected temperature‐dependent swelling properties and explored the impact of the biphenyl comonomers. These studies indicated that with an increase in biphenyl comonomer content, the physical crosslinking increases which leads to a decrease in the swelling ratio. The results from the mechanical tests also indicate the effect of the concentration of biphenyl comonomers. These physically crosslinked polymeric systems with their unique properties have potential applications spanning environmental remediation/sensing, biomedicine, etc. © 2021 Society of Industrial Chemistry.
Structure and impact properties of a thermoplastic elastomer/silly putty blend
Authors: Zhao Zhigang , Liu Fang , Yang Xue , Zhang Dan , Luan Shifang , Xu Donghua , Shi Tongfei 
Published: November 2021

AbstractThe structure and impact properties of a thermoplastic elastomer/silly putty blend are explored. The impact‐resistant materials are made with polyolefin‐based thermoplastic elastomer HYBRAR™ 5127 and silly putty DOWSIL™ 3179. The peak impact force decreases with the content of silly putty, as part of the impact energy might be dissipated by the dissociation of boron–oxygen dynamic dative bonds in silly putty. It is also observed that the crack behavior of samples under impact is related to the phase structure of silly putty in the samples. For the samples with high content of silly putty, a macroscopic crack is observed for these samples under impact, as a crack can spread in the continuous phase structure of silly putty. Different energy dissipation ratios in rheological, compression and impact experiments are also observed. It is concluded that the results of linear dynamic oscillatory shear and compression at a low strain rate cannot give a direct predication of energy dissipation ratios of samples under impact at a high strain rate. © 2021 Society of Industrial Chemistry.
Regio‐regular and cross‐conjugated poly(thienylene vinylene)s through acyclic diene metathesis
Authors: Bader Yousef M. Katba , Guan Chao , Qin Yang 
Published: November 2021

AbstractPoly(thienylene vinylene)s (PTV's) are early examples of conjugated polymers but have not been extensively studied when compared with closely analogous polythiophenes. PTV's synthesized through previously reported techniques are similar in structures that contain various alkyl or alkoxy side‐chains that exert limited impact on the polymer electronic properties. Herein, we report the preparation of a series of regio‐regular PTV's (rr‐PTV's) bearing cross‐conjugated side‐chains through ADMET polymerization of a common brominated di(thienylene vinylene) (DTV) monomer followed by PPM reactions on the resulting brominated PTV. These new polymers contain a bulky silyloxy alkyl side‐chain and a functionalized thiophene moiety on every main‐chain thiophene unit, and their regio‐regular placement is confirmed by NMR spectroscopy. The thienyl based side‐groups broaden polymer absorption ranges and at the same time lead to uncommon emission properties that are results of light‐induced charge transfer events between the polymer main‐chains and side‐chains. Removal of the silyl groups on one of these rr‐PTV's led to insoluble materials and x‐ray diffraction experiments on the collected solids displayed distinct scattering peaks that are absent from similarly functionalized regio‐random PTV's reported previously, thus suggesting better crystallinity originated from regio‐regularity.
Crystal structure of Aedes aegypti trypsin inhibitor in complex with μ‐plasmin reveals role for scaffold stability in Kazal‐type serine protease inhibitor
Authors: Walvekar Varsha Ashok , Ramesh Karthik , Jobichen Chacko , Kannan Muthu , Sivaraman J. , Kini R. Manjunatha , Mok Yu Keung 
Published: November 2021

AbstractKazal‐type protease inhibitor specificity is believed to be determined by sequence of the reactive‐site loop that make most, if not all, contacts with the serine protease. Here, we determined the complex crystal structure of Aedes aegypti trypsin inhibitor (AaTI) with μ‐plasmin, and compared its reactivities with other Kazal‐type inhibitors, infestin‐1 and infestin‐4. We show that the shortened 99‐loop of plasmin creates an S2 pocket, which is filled by phenylalanine at the P2 position of the reactive‐site loop of infestin‐4. In contrast, AaTI and infestin‐1 retain a proline at P2, rendering the S2 pocket unfilled, which leads to lower plasmin inhibitions. Furthermore, the protein scaffold of AaTI is unstable, due to an elongated Cys‐V to Cys‐VI region leading to a less compact hydrophobic core. Chimeric study shows that the stability of the scaffold can be modified by swapping of this Cys‐V to Cys‐VI region between AaTI and infestin‐4. The scaffold instability causes steric clashing of the bulky P2 residue, leading to significantly reduced inhibition of plasmin by AaTI or infestin‐4 chimera. Our findings suggest that surface loops of protease and scaffold stability of Kazal‐type inhibitor are both necessary for specific protease inhibition, in addition to reactive site loop sequence. PDB ID code: 7E50.
Computing and comparative analysis of topological invariants of Y‐junction carbon nanotubes
Authors: Nadeem Muhammad Faisal , Shabbir Ayesha 
Published: November 2021

AbstractRecent findings of diverse forms of carbon nanostructures have encouraged research on their applications in several areas. They are used as a structural material in electronic and optical devices, involving transistors, photodetectors, plastic, biological sensors, pharmaceutical and medicine, and drug delivery systems. Since the discovery of Y‐shaped carbon nanotubes (CNTs) junctions, they have drawn interest for future electron devices, for example, three‐terminal transistors, amplifiers, and switches. A topological index is a number that is used to study the physicochemical properties of chemical structures. In this paper, we are providing topological properties of CNT Y‐junctions. The results obtained for different types of Y‐junction graphs appeared with comparisons. According to the best of our knowledge and literature, this is the first report about topological indices on this class of CNT junctions.
Quantitative structure–property relationship of Ev‐degree and Ve‐degree based topological indices : physico‐chemical properties of benzene derivatives
Authors: Rauf Abdul , Naeem Muhammad , Bukhari Saira Usman 
Published: November 2021

AbstractA quantitative structure–property relationship study was performed for the prediction of physical properties of 22 benzene derivatives using ev‐degree and ve‐degree topological indices. These topological indices correlate certain physico‐chemical property with the chemical structure (like molecular weight, enthalpy, boiling point and π‐electron energy of β‐unit of benzene derivatives). At first, a simple linear regression model was developed using ve‐degree and ev‐degree topological indices and the certain physical properties of the considered benzene derivatives. It is found that the atom bond connectivity index () possesses the best correlating ability among several topological indices to predict the boiling point, the ve‐degree based Randić index is the best predictor of enthalpy, the ev degree based Randić index is the best predictor of π‐electron energy, the sum connectivity index is the best predictor of molecular weight. Second, multiple linear regressions were used for prediction the physical properties (molecular weight, boiling point, enthalpy and π‐electron energy of β‐unit) on the basis of six predictor such as , , , , , and indices. This multi‐linear regression model shows the 100% variation in π‐electron energy of β‐unit. A Maple software based algorithm is used for the calculations of topological indices and the statistical analysis is performed with the SPSS software. The calculations of the ev and ve degree based topological indices of chemical structure of styrene‐butadiene rubber are presented at the end to illustrate the given Maple algorithm.
Firms' responses to changes in frictions in related human capital factor markets
Authors: Allen W. David , Schepker Donald J. , Chadwick Clint 
Published: November 2021

AbstractResearch SummaryStrategic human capital scholars suggest that firms' human capital rents are greater when labor market frictions are more prevalent. Taking this argument further, we suggest that when frictions for one type of human capital decrease, firms are motivated to place greater emphasis on human capital that is interdependent in production where frictions are unchanged. Empirically, we exploit an exogenous institutional change in the National Football League to demonstrate that coaching (managerial) dismissal and replacement is more likely to occur (and is influenced by a wider variety of information) after frictions for player (production worker) human capital decrease. Our findings suggest adding a new dimension—tradeoffs between related labor market segments—to the scholarly conversation about how firms manage their human capital (and other resources) strategically.Managerial SummaryWe often point to the existence of labor market frictions for different types of human capital as reasons why firms would emphasize one type of human capital over another. But changes in frictions in markets for related human capital, the present focus, can influence this decision as well. In particular, our study demonstrates that when the NFL implemented free agency and a salary cap in the market for player talent in 1993, limiting the ability of teams to stockpile talented players, NFL teams responded by increasing their emphasis on coaching talent in the production of wins. This increased emphasis manifested in more frequent coaching dismissals and a greater influence of different types of information on the desirability of replacing a team's head coach after 1993.
Optimizing Microenvironment of Asymmetric N,S‐Coordinated Single‐Atom Fe via Axial Fifth Coordination toward Efficient Oxygen Electroreduction
Authors: Li Longbin , Huang Senhe , Cao Rui , Yuan Kai , Lu Chenbao , Huang Bingyu , Tang Xiannong , Hu Ting , Zhuang Xiaodong , Chen Yiwang 
Published: November 2021

AbstractSingle‐atom catalysts (SACs) are attractive candidates for oxygen reduction reaction (ORR). The catalytic performances of SACs are mainly determined by the surrounding microenvironment of single metal sites. Microenvironment engineering of SACs and understanding of the structure–activity relationship is critical, which remains challenging. Herein, a self‐sacrificing strategy is developed to synthesize asymmetric N,S‐coordinated single‐atom Fe with axial fifth hydroxy (OH) coordination (Fe−N3S1OH) embedded in N,S codoped porous carbon nanospheres (FeN/SC). Such unique penta‐coordination microenvironment is determined by cutting‐edge techonologies aiding of systematic simulations. The as‐obtained FeN/SC exhibits superior catalytic ORR activity, and showcases a half‐wave potential of 0.882 V surpassing the benchmark Pt/C. Moreover, theoretical calculations confirmed the axial OH in FeN3S1OH can optimize 3d orbitals of Fe center to strengthen O2 adsorption and enhance O2 activation on Fe site, thus reducing the ORR barrier and accelerating ORR dynamics. Furthermore, FeN/SC containing H2O2 fuel cell performs a high peak power density of 512 mW cm−2, and FeN/SC based Znair batteries show the peak power density of 203 and 49 mW cm−2 in liquid and flexible all‐solid‐state configurations, respectively. This study offers a new platform for fundamentally understand the axial fifth coordination in asymmetrical planar single‐atom metal sites for electrocatalysis.
Acacia catechu seed extract provokes cytotoxicity via apoptosis by intrinsic pathway in HepG2 cells
Authors: Thangavelu Lakshmi , Geetha Royapuram Veeraragavan , Devaraj Ezhilarasan , Dua Kamal , Chellappan Dinesh Kumar , Balusamy Sri Renukadevi 
Published: November 2021

AbstractAcacia catechu Willd (Fabaceae) is a thorny tree widely distributed in India and commonly used as traditional Ayurvedic medicine for various ailments. The current study evaluates the cytotoxic potentials of A. catechu ethanolic seed extract (ACSE) in HepG2 cells, a human hepatocellular carcinoma cell line. The HepG2 cells were treated with 0.1, 0.3, 1, 3, 10, 30, 100, 300 and 1000 μg/ml of ACSE and the cytotoxic effect was evaluated by MTT and lactate dehydrogenase (LDH) leakage assays. The IC50 of ACSE was found at 77.04 μg/ml and therefore, further studies were carried out with the concentrations of 35 and 70 μg/ml. The intracellular reactive oxygen species (ROS) generation and apoptosis‐related morphological changes were evaluated. Gene expressions of Bax, Bcl‐2, cytochrome C (Cyt‐c), caspases‐9 and 3 were analyzed by qPCR. The ACSE treatments caused LDH leakage was associated with an increased ROS generation. The increased ROS generation was associated with the downregulation of intracellular antioxidant enzyme superoxide dismutase and reduced glutathione content. AO/EB and PI staining also confirmed chromatin condensation and apoptosis. The flow cytometric analysis showed an accumulation of HepG2 cells at sub G0/G1 (apoptotic) phase upon ACSE treatments. The ACSE induced cytotoxicity and oxidative stress were related to increased apoptotic marker gene expressions such as Bax, Cyt‐c, caspase‐9 and 3, and decreased anti‐apoptotic marker Bcl‐2. The current finding suggests that ACSE has apoptosis‐inducing potential via the mitochondrial pathway in HepG2 cells.
Cryptorchid investigation of an adult cob pony with unknown history
Authors: Watkins Moira 
Published: November 2021

AbstractA 400 kg, male, adult cob pony presented with a history of stallion‐like behaviour without testicles palpable. The blood oestrone sulphate level was 4.90 ng/ml, consistent with cryptorchidism (0.1–10.0 ng/ml; IDEXX). Age was estimated at 8 years by dentition. Previous veterinary treatment history was unavailable. Examination under general anaesthesia found no evidence of prior surgical castration. Investigation of the inguinal region was unremarkable with no evidence of an inguinal extension of the gubernaculum testis or vaginal process on either side. Exploratory laparotomy of the right abdomen revealed a cystic, 5 × 8 cm mass with homogenous tapering stalk. This was removed by emasculation. Histological examination identified the mass as a benign testicular teratoma. Blood anti‐Mullerian hormone 5 days after the surgery measured 0.9 ng/ml. The pony made a full recovery and the owner reported the behavioural issues have resolved.
Optimization of fluoride adsorption from aqueous solution over mesoporous titania‐alumina composites using Taguchi method
Authors: Al Mesfer Mohammed K. , Danish Mohd , Shah Mumtaj 
Published: November 2021

AbstractThe optimization of fluoride removal from aqueous media was studied over the mesoporous titania‐alumina composites using Taguchi method‐based L25 orthogonal array experimental design. The chemical structure, surface chemistry, and morphology of as‐prepared composite adsorbents were studied utilizing various analytical methods. The findings of the characterization demonstrated that the produced composites have high textural qualities, which are conducive to enhanced fluoride adsorption. The optimum conditions for maximum percentage removal of fluoride from aqueous solution were found as adsorbent type as TA75, adsorbent dose 4 g L−1, initial concentration of fluoride 40 ppm, solution pH 3 with a treatment time of 60 min. Under the optimum conditions, 98% of fluoride adsorption was achieved. Analysis of variance revealed that the solution pH followed by the adsorbent dose was the most significant for fluoride adsorption. The Langmuir model and pseudo‐second‐order kinetic model fit the adsorption data well, and the TA75 adsorbent had a maximum Langmuir fluoride adsorption capacity of 34.48 mg g−1 at pH = 3. The thermodynamic information suggests that the adsorption was spontaneous and endothermic under the given operating conditions. The synergic combination of Ti–Al nanoparticles demonstrated a high percentage removal of fluoride under the optimized operating conditions.Practitioner Points
The Taguchi method‐based design of the experimental approach was implemented in the fluoride adsorption process.
Mesoporous titania‐alumina composites with 0 to 100 wt.% of alumina in titania were prepared and applied to remove fluoride from an aqueous solution.
Solution pH was the most influential parameter for the fluoride adsorption process, while the synergistic combination of 75 wt.% alumina in titania showed the maximum adsorption capacity.
Variational models for the interaction of surfactants with curvature – existence and regularity of minimizers in the case of flexible curves
Authors: Brand Christopher , Dolzmann Georg , Pluda Alessandra 
Published: November 2021

AbstractExistence and regularity of minimizers for a geometric variational problem is shown. The variational integral models an energy contribution of the interface between two immiscible fluids in the presence of surfactants and includes a Helfrich type contribution, a Frank type contribution and a coupling term between the orientation of the surfactants and the curvature of the interface. Analytical results are proven in a one–dimensional situation for curves.