bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predictors of recurrence of atrial tachyarrhythmias after pulmonary vein isolation by functional and structural mapping of nonparoxysmal atrial fibrillation
Authors: Kumagai Koji , Sato Tsukasa , Kurose Yuki , Sumiyoshi Takenori , Hasegawa Kaoru , Sekiguchi Yuko , Yambe Minoru , Komaru Tatsuya 
Published: December 2021

AbstractBackgroundThis study aimed to evaluate the predictors of recurrence of atrial tachyarrhythmias by structural and functional mapping: voltage, dominant frequency (DF), and rotor mapping after a pulmonary vein isolation (PVI) in nonparoxysmal atrial fibrillation (AF) patients.MethodsA total of 66 nonparoxysmal AF patients were prospectively investigated. After the PVI, an online real‐time phase mapping system was used to detect the location of rotors with critical nonpassively activated ratios (%NPs) of ≧50% in each left atrial (LA) segment, and high‐DFs of ≧7 Hz were simultaneously mapped. After restoring sinus rhythm, low‐voltage areas (LVAs < 0.5 mV) were mapped using the Advisor HD grid catheter (HDG).ResultsSixty‐four of 66 (97%) AF patients had minimum to mild LVAs regardless of an enlarged LAD and LA volume (45 ± 6.0 mm and 141 ± 29 ml). There were no significant differences in the max and mean DF values and %NPs between the patients with and without recurrent atrial tachyarrhythmias. However, there was a significant difference in the LVA/LA surface area between the patients with and without recurrent atrial tachyarrhythmias (p = .004). Atrial tachyarrhythmia freedom was significantly greater in those with LVAs of ≤3.3% than in those >3.3% after one procedure over 11.6 ± 0.8 months of follow‐up (77.1% vs. 33.3%, p < .001). In a multivariate analysis, the LVA/LA surface area after the PVI (HR 1.079; CI, 1.025–1.135, p = .003) was an independent predictor of AF recurrence.ConclusionsThe predictor of atrial tachyarrhythmia recurrence after the PVI was LVAs rather than DFs and rotors in nonparoxysmal AF patients.
Evaluation of algal active compounds as potent antibiofilm agent
Authors: Nag Moupriya , Lahiri Dibyajit , Dey Ankita , Sarkar Tanmay , Joshi Sanket , Ray Rina R. 
Published: December 2021

AbstractBiofilm is the syntrophic association of microbial colonies that remain adhered to the biotic and abiotic surfaces with the help of self‐secreted polymeric substances also termed extracellular polymeric substances. Chronic pathogenicity caused by biofilm‐associated pathogenic microorganisms becomes a significant threat in biomedical research. An extensive search is being made for the antibiofilm agents made from natural sources or their biogenic derivatives due to their effectivity and nontoxicity. Algae being the producer of various biogenic substances are found capable of disintegrating biofilm matrix and eradication of biofilm without exerting any deterrent effect on other biotas in the ecosystem. The current trend in phycological studies includes the exploration of antifouling efficacy among various algal groups. The extracts prepared from about 225 microalgae and cyanobacteria species are found to have antibiofilm activity. Polyunsaturated fatty acids are the most important component in the algal extract with antibacterial and antibiofilm properties. The antibiofilm activity of the sulfated polysaccharides extracted from a marine alga could be effectively used to remove dental biofilm. Algal extracts are also being used for the preparation of different biogenically synthesized nanoparticles, which are being used as potent antibiofilm agents. Genome editing of algal species by CRISPR/Cas9 may make precise modifications in the algal DNA for improving the algal strains and production of a more effective antibiofouling agent.
Study of Different Natural Dyes for Dye‐Sensitized Solar Cell
Authors: Nagde Kalpana R. 
Published: December 2021

AbstractIn this paper extract of pomegranate, beet root and black berry are used to study the performance of these dyes on the DSSCs. The UV‐vis spectra of natural dyes suggest that pomegranate and blackberry have a better absorptive capacity at 300–550 nm, which is attributed to higher concentration of pigment with anthocyanin. From the overall study of natural dyes, it is observed that the blackberry exhibits optimal performance and power conversion efficiency reaches up to 0.160% due to higher absorption coefficient as compared to other natural dyes under study.
Synthesis of Bioactive 1,4‐DHPs Using Sulfated Tin Oxide as an Efficient Solid Superacid Catalyst
Authors: Kagne Raju , Niwadange Sandeep , Kalalawe Virbhadra , Khansole Gopinath , Munde Dashrath 
Published: December 2021

AbstractA novel synthetic approach is formulated for the synthesis of 1,4‐dihydropyridine derivatives via one pot condensation of aromatic aldehydes, β‐keto esters, and ammonium hydroxide by using prepared STO as solid super acid heterogenous catalyst in ethanol at reflux condition. The synthesized sulfated tin oxide is confirmed by FTIR, XRD, and SEM EDX. The surface area of the catalyst is measured using BET plots. The reactions are optimized for different solvents and loading of catalyst. The yields of all 1,4‐dihydropyridine derivatives are observed in the range of 80–92%. All the synthesized DHPs are authenticated by spectral analysis. The use of environmentally benign catalyst, good atom economy, low cost and ease of work up makes this exercise efficient and sustainable.
Influence of Zinc Doped Structural Properties of Nano‐MgFe2O4 Ferrites Synthesized by Co‐Precipitation Method
Authors: Vishwarup Rakesh , Kulkarni Akshay B. , Manohara S. R. , Mathad Shridhar N. 
Published: December 2021

AbstractMg‐Zn ferrites are a class of soft magnetic materials that possess very good structural, electrical, and magnetic properties. Mg‐Zn ferrites are prepared by eco‐friendly co‐precipitation method at relatively low temperature. Formation of spinel cubic ferrite is confirmed by using x‐ray diffraction studies and lattice parameters of the samples ranging from 8.323–8.361A°. Detailed staple parameters like lattice constant, crystallite‐size, x‐ray density, bond length, inter‐ionic distance are determined employing XRD data. The W‐H plot and Size‐Strain plots are extensively studied and the results are compared. SEM analysis furnishes surface morphology and grain size (in the range 3.7–4.3 µm) of particles of Mg‐Zn samples.
Complete Micro‐Structural Analysis and Elastic Properties of Sm3+‐Doped Ni‐Mn‐Zn Mixed Spinel Ferrite Nanoparticles
Authors: More Vikram , Kadam Sanskruti , Kadam Supriya , Wadgane Santosh , Kadam Ramkrishna , Alone Suresh 
Published: December 2021

AbstractA series of Ni‐Mn‐Zn mixed spinel ferrite doped with Sm3+ ions is prepared by using sol‐gel auto‐combustion technique. Single phase cubic spinel structure of all the samples is confirmed by using XRD analysis. Incorporation of Sm3+ ions in Ni‐Mn‐Zn ferrites increases the lattice parameter from 8.4105 to 8.4134 Å. Williamson – Hall (W‐H) and strain size plot (SSP) analysis confirms the tensile‐type strain induced in the crystal lattice, which increases with the addition of Sm3+ ions. Average crystallite size estimated from Scherrer equation is found in the range 21.7–24.9 nm, which in good agreement with the results obtained from W‐H and SSP analysis. Infrared spectra recorded in the range 350–800 cm−1 reveals the characteristic features of spinel ferrites. Higher frequency band ν1 is observed near 580 cm−1 and lower frequency band ν2 is observed near 380 cm−1. By using the IR data, elastic constant (stiffness constant) and elastic moduli (Young's modulus, bulk modulus, and rigidity modulus) are estimated. Debye temperature obtained from Anderson formula ranging from 535 to 562 K and from Waldron equation ranging from 676 to 713 K with the substitution of Sm3+ ions.
Synthesis, Characterization, and Photocatalytic Activity of NiO Nanoflowers
Authors: Bodhankar Pradnya M. , Jadhav Sapna , Sarawade Pradip B. 
Published: December 2021

AbstractThe sustainable development of pollution‐free technologies for environmental remediation has concerned significant attraction due to rapid growth of industrialization. Herein, synthesis of nanoflower‐like NiO porous nanostructures prepared from different nickel precursors by solvothermal method in combination with calcination treatment is reported. The obtained porous NiO‐Ac (prepared from nickel acetate) and NiO‐S (prepared from nickel sulfate) nanostructures are analyzed by a powder X‐ray diffractometer (XRD), transmission electron microscope (TEM), and BET to determine their structure, morphology, and surface area. Photocatalytic measurement of NiO‐Ac and NiO‐S demonstrates that, these nanostructures show excellent photo degradation behavior toward methylene blue (MB) under ultraviolet radiation. About 85% of MB in 100 min is removed using NiO‐S nanostructured catalyst. Compared with NiO‐Ac, the porous NiO‐S nanoflowers exhibit higher photocatalytic activity due to their large surface area (100.79 m2 g−1) and smaller band gap (3.0 eV).
Thermal, Electrical, and Sensing Properties of Recycled HDPE/Carbonaceous Industrial Waste Composites
Authors: NK Sajeel , Mohammad Houkan , Kannan Karthik , Saleh Mohammed Ismail , Sadasivuni Kishor Kumar 
Published: December 2021

AbstractThis work is an endeavor to contemplate a value‐added conductive plastic composite material derived as recycled plastic depending on polyethylene (PE)/carbon black (CB). We choose to add CB as a filler material to enhance the electrical conductivity as well as other properties associated with the composite. The solution mixing method is adopted to develop this composite where the consequences of CB loadings on various parameters like processability, morphology, and thermal stability of the composites are examined. The perceived better filler–matrix interaction and filler dispersion observed in the scanning electron microscopy (SEM) is the underlying reason behind the improved properties. The thermal conductivity of high‐density polyethylene (HDPE) with 90 wt% CB is 2.25 W mK−1. Electrical conductivity increases with the increasing amount of the CB loading. The electrical conductivity of 60 wt% CB is 1 × 10−5 S cm−1. Electrical, thermal, and dielectric studies of the prepared plastic composite material will be studied.
Investigation of Super‐Capacitive Properties of Nanocrystalline Copper‐Zinc (Cu0.5Zn0.5Fe2O4) Ferrite Nanoparticles
Authors: Kharat Prashant B. , Somvanshi Sandeep B. , Somwanshi Saurabh B. , Mopari Anuja M. 
Published: December 2021

AbstractA comparative study is made between the structure and electrochemical properties of Copper‐Zinc (Cu0.5Zn0.5Fe2O4) ferrite nanoparticles prepared by chemical co‐precipitation. The obtained ferrites are characterized by FT‐IR, XRD, BET, and SEM techniques. The single‐phase cubic formation of Cu0.5Zn0.5Fe2O4 nano ferrites without any impurity peaks is confirmed by XRD analysis. FT‐IR spectrum exposes the occurrence of vibrating modes analogous to the cubic‐spinel ferrite structure of Cu0.5Zn0.5Fe2O4 nano ferrites. The magnetic hysteresis curve displays the superparamagnetic nature of the Cu0.5Zn0.5Fe2O4 nano ferrites. The electrochemical properties of obtained ferrites are studied using cyclic voltammetry, charge‐discharge, and electrochemical impedance spectroscopy. The as‐synthesized Cu0.5Zn0.5Fe2O4 sample acts as an excellent electrode material in a supercapacitor with a high specific capacitance energy density and a power density.
Layered Polyaniline–Manganese Oxide Nanocomposite Electrode Material for Supercapacitor Application
Authors: Kadam Snehal L. , Ingole Rahul S. , Tiwari Nidhi , Kulkarni Shrinivas 
Published: December 2021

AbstractIn the present research work, layered nanocomposite of polyaniline–manganese oxide (PANI/MnO2) electrodes is synthesized using the potentiostatic electrodeposition method. The structural and morphological properties of the nanocomposite electrode materials are tested using X‐ray diffraction (XRD) and field emission‐scanning electron microscopy (FE‐SEM) techniques. The XRD analysis shows the amorphous nature of the electrode material. The FE‐SEM micrographs show porous morphology. The supercapacitive properties are investigated using cyclic voltammetry, galvanostatic charge‐discharge, cyclic stability, and electrochemical impedance spectroscopy techniques in 1 M Na2SO4 electrolyte. The layered nanocomposites show maximum values of specific capacitance which is 582 F g−1 at a scan rate of 5 mV s−1. The synergistic effect of layered nanocomposite leads to enhancement in the supercapacitive performance than the pristine electrode.
Comparative Studies on Synthetic Strategies for the Growth of CuO Nanostructures and Their Significant Impact on Supercapacitive Performance
Authors: Yadav Suhasini J. , Pawale Rohan S. , Bobhate Pradip A. , Gonugade Madhuri D. , Gurav RutujaN. , Tarwal N. L. , Kim Jin H. , Gurav Kishor V. 
Published: December 2021

AbstractThe copper oxide (CuO) nanostructures are synthesized by various simple and cost‐effective chemical methods. The morphology of metal oxide nanostructures depends on the synthetic strategy. The electrochemical behavior primarily depends on the morphology of the electrode. The significant impact of synthetic strategy on the structural, morphological, and subsequently on the supercapacitive performance of CuO nanostructures is studied. The chemical bath deposition (CBD) leads to well defined growth of 1D nanostructures, while the intermittent growth process (successive ionic layer adsorption and reaction, SILAR) leads to nanoparticulate morphology. CBD grown CuO nanorods have shown comparatively higher capacitance (207 F g−1) than CuO nanoparticles (147 F g−1) at current density of 2 A g−1.
Effect of carbon nanotubes reinforcement on eigenmodes of multi‐smart core sandwich composite cylindrical shell panels
Authors: Shankar A. N. , Murali Krishna S. M. , Chebolu Rohinikumar , K. S. Singholi Ajay , Singh Rasmeet , Rajeshkumar S. 
Published: December 2021

AbstractThis study investigates the dynamic responses of carbon nanotubes (CNT) reinforced composite sandwich shells with multi magnetorheological elastomer (MRE) core. The CNT reinforced composite skin layers are made by using hand layup technique. An experimental modal test has been carried for with and without CNT reinforced composite cylindrical shells under clamped free condition. The 3D finite element model is verified by comparing the obtained natural frequencies with experimental results. The numerical results indicate that the CNT reinforced composite multi‐MRE cylindrical sandwich shell greatly influences the natural frequencies compared with single‐MRE cylindrical sandwich shell. The effect of many parameters on the natural frequencies of the CNT reinforced composite multi‐MRE cylindrical sandwich shells is also discussed, including the weight percent of CNT, magnetic fields, and support conditions.
Vibrational analysis of glass/ramie fiber reinforced hybrid polymer composite
Authors: Thiyagu Chenniappan , Narendrakumar Uttamchand 
Published: December 2021

AbstractNatural fiber reinforced hybrid polymer composites have gained extensive applications in recent decades owing to their damping, low density, biodegradability, and low‐cost benefits. This research explores the impact of the surface treatment, and the number of ramie fiber layers on the vibrational and mechanical characteristics of a glass/ramie fiber reinforced hybrid polymer composite. The composite is made of outer layer (glass fiber) and inner layer (ramie fiber) at different concentrations (varying between 2, 3, and 4). The ramie was pre‐treated with sodium hydroxide (NaOH) at different weight percentages (1%, 2%, and 5%). The composites have been fabricated using the vacuum bag technique. The composites have been characterized for chemical, mechanical, morphological, and free vibrational analysis. Fourier transform infrared spectroscopy and scanning electron microscope have been used to study the chemical characteristics and morphological study of the composites respectively. The mechanical properties of the composite were evaluated through tensile and flexural testing. The hybrid composite reinforced with two layers of ramie fiber as the core with 2% pre‐treated shows the maximum tensile strength of 120 MPa and flexural modulus of 12,147 MPa. Overall, the hybridization and NaOH pre‐treatment to certain ratio helps in increase in the hybrid composite's mechanical strength compared to the natural fiber composite.
Double mutations far from the active site affect cold activity in an Antarctic halophilic β‐galactosidase
Authors: Laye Victoria J. , DasSarma Shiladitya 
Published: December 2021

AbstractThe Antarctic haloarchaeon, Halorubrum lacusprofundi, contains a polyextremophilic family 42 β‐galactosidase, which we are using as a model for cold‐active enzymes. Divergent amino acid residues in this 78 kDa protein were identified through comparative genomics and hypothesized to be important for cold activity. Six amino acid residues were previously mutated and five were shown by steady‐state kinetic analysis to have altered temperature‐dependent catalytic activity profiles via effects on Km and/or kcat compared to the wild‐type enzyme. In this follow‐up study, double‐mutated enzymes were constructed and tested for temperature effects, including two new tandem residue pairs (N180T/A181T and T383A/S384A), and pairwise combination of the single residue mutations (N251D, F387L, I476V, and V482L). All double‐mutated enzymes were found to be more catalytically active at moderate and/or less active at colder temperatures than wild‐type, with both Km and kcat effects observed for the two tandem mutations. For pairwise combinations, a Km effect was seen when the surface exposed F387L mutation located in a domain A TIM barrel α helix 19 Å from the active site was combined with two internal residues, N251D or V482L. When another surface exposed mutation I476V located in a coiled region of domain B 25 Å from the active site was paired with N251D or V482L, a kcat effect was observed. These results indicate that temperature‐dependent kinetic effects may be complex and subtle and are mediated by a combination of a small number of residues distant from the active site via changes to the hydration shell and/or perturbation of internal packing.
C‐POOL: A scheme for modelling convective cold pools in the Met Office Unified Model
Authors: Rooney Gabriel G. , Stirling Alison J. , Stratton Rachel A. , Whitall Michael 
Published: December 2021

AbstractA new parametrization scheme representing the lifecycle and effects of convective cold pools (C‐POOL) is presented. The scheme comprises a column‐crossing prognostic model of the initiation by downdraughts, interaction and decay of cold pools, based upon approximations taken from similarity modelling of gravity currents. The prognostic variables are drawn upon to feed back into the convection parametrization scheme. These feedbacks affect the convective diagnosis, initiation from the boundary layer, parcel ascent and entrainment. Tests of the model show that it improves representation of the diurnal cycle of tropical rainfall, previously well‐known as a weakness of parametrized convection.
Mapping of soil organic carbon using machine learning models: Combination of optical and radar remote sensing data
Authors: Zhou Yang , Zhao Xiaomin , Guo Xi , Li Yi 
Published: December 2021

AbstractSoil organic C (SOC) plays an important role in soil quality. Thus, it is of great significance to know the spatial distribution characteristics of SOC. Environmental variables, such as natural predictors, remote sensing (RS) variables, and digital soil mapping approaches have been widely used in SOC prediction. However, it is still challenging to determine which methods and variables are effective to map SOC in farmland. In this study, we compare the performance of three machine learning models, including random forest, Cubist, and the support vector machine model for the prediction of SOC contents using RS variables, topographic variables, climate variables, soil property variables, and spatial position variables as environmental covariates. The recursive feature elimination (RFE) technique was used to select optimal variables. Of the 130 sampling sites of the cultivated layer that were collected in Shanggao county, 70% of the data were used for training and 30% for validation. Prediction accuracy and uncertainty was quantified using the bootstrap approach with 100 iterations. The performance of the model was verified by the mean absolute error, RMSE, R2, and Lin's concordance correlation coefficient (CCC); the SD was used as a measure of prediction uncertainty. Results showed that the Cubist model combined with the RFE method (Cubist_RFE) had a mean R2, RMSE, and SD of .84, 2.39 g kg–1, and 0.73 g kg–1, respectively, which showed the highest prediction accuracy and the lowest uncertainty. The soil property variables (soil alkaline hydrolysis N and pH) and RS variables (soil adjusted vegetation index, enhanced vegetation index, and band7 of Sentinel‐2) were the controlling factors of SOC prediction. Thus, the results indicate the potential of the Cubist model in SOC prediction, and the combination of the optical and radar RS data is a viable way for predicting SOC.
The CEO beauty premium: Founder CEO attractiveness and firm valuation in initial coin offerings
Authors: Colombo Massimo G. , Fisch Christian , Momtaz Paul P. , Vismara Silvio 
Published: December 2021

AbstractResearch summaryWe apply insights from research in social psychology and labor economics to the domain of entrepreneurial finance and investigate how founder chief executive officers' (founder CEOs') facial attractiveness influences firm valuation. Leveraging the novel context of initial coin offerings (ICOs), we document a pronounced founder CEO beauty premium, with a positive relationship between founder CEO attractiveness and firm valuation. We find only very limited evidence of stereotype‐based evaluations, through the association of founder CEO attractiveness with latent traits such as competence, intelligence, likeability, or trustworthiness. Rather, attractiveness seems to bear economic value per se, especially in a context in which investors base their decisions on a limited information set. Indeed, attractiveness has a sustainable effect on post‐ICO performance.Managerial summaryICOs allow ventures to collect funding from investors using blockchain technology. We leverage this novel funding context, in which information on the ventures and their future prospects is scarce, to empirically investigate whether the founder CEOs' physical attractiveness is associated with increased funding (i.e., amount raised) and post‐funding performance (i.e., buy‐and‐hold returns). We find that ventures with more attractive founder CEOs outperform ventures with less attractive CEOs in both dimensions. For ICO investors, this suggests that ICOs of firms with more attractive founder CEOs are more appealing investment targets. Our findings are also interesting for startups seeking external finance in uncertain contexts, such as ICOs. If startups can appoint attractive leaders, they may have better access to growth capital.