bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of BaO Doping on the Structural, ac Conductivity, and Dielectric Properties of BiFeO3 Multiferroic Nanoparticles
Authors: Ayoub M. S. , Morad Ibrahim , Ali H. Elhosiny , Mostafa M. M. , El–Desoky M. M.
Published: February 2021

The Bi1 − xBaxFeO3 (BiBaFeO3) multiferroic nanoparticles with different Ba molar concentrations were fabricated in reliance on the solid-state reaction technique. Nanostructures of the prepared samples were confirmed by X-ray diffraction (XRD) together with Fourier transforms infrared (FTIR) spectroscopy, whereas the ac conductivity, dielectric and ferroelectric features were examined depending on the RLC Bridge, and Sawyer–Tower circuit. XRD patterns displayed the creation of rhombohedral–hexagonal single-phase of BiBaFeO3. The formation of BiBaFeO3 multiferroic nanoparticles was confirmed by FTIR spectra. Curie temperature (TC) was observed around 1121–1189 K. Ferroelectric polarization was enhanced with remnant polarization of 88.8 µC/cm2 by Ba2+ ions substitution at x = 0.15 mol%. Besides, ac electrical conductivities as a function of frequency as well as temperature were reported for all BiBaFeO3 multiferroic nanoparticles, which exhibit a strong frequency dependence with conduction mechanism is the correlated barrier hopping (CBH) model. The obtained high polarization and Curie temperature enhance their use in information storage devices.
A Novel Severe Plastic Deformation Method for Manufacturing Al/Mg bimetallic Tube
Authors: Tian Ye , Hu Hongjun , Zhang Dingfei
Published: February 2021

A new severe plastic deformation for manufacturing Al/Mg bimetallic tube called TES (Tube Extrusion Shearing) process, which combines direct extrusion with two step shearing, is developed to Al/Mg bimetallic tube. To explore the deformation mechanism for Al/Mg bimetallic tube during TES process, both experiments and numerical simulations have been carried out. The stroke loads during TES process of Al/Mg bimetallic tubes have been simulated by establishing three-dimensional finite element model. Experiments show that by use of TES process the microstructures can be refined to 50% of the original grain size and with more uniform grain distribution. TES process could improve hardness obviously by comparing which fabricated by direct extrusion. Numerical results indicate TES increases the cumulative strains effectively by direct extrusion and additional shearing. The micro-structures and mechanical properties of the bonded layer were analyzed, The results showed that under the extrusion temperature of 420℃, the bonding layer of the sample obtained by extrusion shearing had no hole defects, and the thickness was about 22um, among which the stable layer was about 11um.The average hardness of the bonding layer is 221HV.
Fast Lightweight Accurate Xenograft Sorting
Authors: Zentgraf Jens , Rahmann Sven
Published: February 2021

Motivation: With an increasing number of patient-derived xenograft (PDX) models being created and subsequently sequenced to study tumor heterogeneity and to guide therapy decisions, there is a similarly increasing need for methods to separate reads originating from the graft (human) tumor and reads originating from the host species' (mouse) surrounding tissue. Two kinds of methods are in use: On the one hand, alignment-based tools require that reads are mapped and aligned (by an external mapper/aligner) to the host and graft genomes separately first; the tool itself then processes the resulting alignments and quality metrics (typically BAM files) to assign each read or read pair. On the other hand, alignment-free tools work directly on the raw read data (typically FASTQ files). Recent studies compare different approaches and tools, with varying results. Results: We show that alignment-free methods for xenograft sorting are superior concerning CPU time usage and equivalent in accuracy. We improve upon the state of the art sorting by presenting a fast lightweight approach based on three-way bucketed quotiented Cuckoo hashing. Our hash table requires memory comparable to an FM index typically used for read alignment and less than other alignment-free approaches. It allows extremely fast lookups and uses less CPU time than other alignment-free methods and alignment-based methods at similar accuracy. Several engineering steps (e.g., shortcuts for unsuccessful lookups, software prefetching) improve the performance even further. Availability: Our software xengsort is available under the MIT license at http://gitlab.com/genomeinformatics/xengsort. It is written in numba-compiled Python and comes with sample Snakemake workows for hash table construction and dataset processing.
Characterization, Antimicrobial and Antioxidant evaluation of biofabricated silver nanoparticles from endophytic Pantoea anthophila
Authors: Nirmala C. , Srid M
Published: February 2021

Endophyte mediated nanoparticles fabrication was emerging as a new frontier in nanomedicines that produce high biocompatible and functionalized silver nanoparticles. In this study, silver nanoparticles were successfully biosynthesized from the extracellular extract of endophytic bacterium Pantoea anthophila isolated from the stem of Waltheria indica for the first time. The synthesised nanoparticles were characterized by UV-Visible and Fourier Transform Infra-Red spectroscopy. The structural analysis is done by X-ray diffraction and the stability was studied by dynamic light scattering and particle size analyser. The size and shape were observed by Transmission Electron Microscope, Scanning Electron Microscope and Energy Dispersive X-Ray spectrum. Further, the nanoparticles were evaluated for antimicrobial and antioxidant properties. Synthesized nanoparticle showed a strong absorption band in the UV-Visible range at 410 nm. The average particle size was found to be 16.8 nm with spherical shaped, crystalline nature. Good zones of inhibition at various ranges were detected against a broad range of human pathogenic bacteria and fungi. A strong free radical scavenging activity of silver nanoparticles with IC50 values 30.75, 19.47, 34.59, 41.12, 27.24, 28.16, 36.21 µg/ml was obtained that was comparable to the reference. The study suggests that the silver nanoparticles can be biosynthesised from endophytic P. anthophila metabolites with significant therapeutic potential. With proper validation, the biosynthesised silver nanoparticles can be developed as a promising antiviral and anticancer drug candidate.
Utilization of Alcohol-Based Hand Sanitizers and Associated Health Risks among Healthcare Workers during the COVID-19 Pandemic: A Cross-sectional Study
Authors: Assefa Desta , Gudeta Tadesse
Published: February 2021

Background

Alcohol-based hand sanitizer is a crucial and widely used product to prevent the spreading of corona-virus disease (COVID-19). However, frequent use of alcohol-based hand sanitizer mainly at the point-of-care can cause health risks and shortages in and outside the healthcare facilities.
Objective

The present study was designed to assess the utilization of alcohol-based hand sanitizers and the incidence of associated health risks among healthcare workers during the COVID-19 pandemic.
Method:

A descriptive cross-sectional study was conducted at the Jimma Medical Center, Ethiopia, between April 01 and June 27, 2020. The collected data were analyzed and described using descriptive statistical tests with SPSS version 21.
Results
Ninety-six healthcare workers with 28.69 ± 4.048 years of mean age participated in the study. 95.8% of them used alcohol-based hand sanitizers to prevent COVID-19 virus transmission in the healthcare setting and community. But they encountered challenges to practice hand hygiene with alcohol-based hand sanitizers. The common problems were alcohol-based hand sanitizers unavailability 66(68.8%), costly 50(52.1%), and skin damage 8(8.3%). Most of them experienced health risks such as skin dryness 60(62.5%), skin irritation 27(28.1%), ocular irritation 11(11.5%), cough 11(11.5%), and others. These health risks caused that 9(9.4%) of them do not practice hand hygiene by alcohol-based hand sanitizers (p-value = 0.999).
Conclusion

To stay safe from COVID-19, healthcare workers faced different challenges, such as access to alcohol-based hand sanitizers and reported health risks. Therefore, the regulatory and public health bodies should promote local production of alcohol-based hand sanitizers with careful follow-up, and its health risks management plan should gain attention.
Splenic Vein Stenting for Recurrent Chylous Ascites in Sinistral Portal Hypertension: A Case Report
Authors: Covello Brian , Miller Jacob , Fourzali Roberto
Published: February 2021

Background: Sinistral portal hypertension results from obstruction or stenosis of the splenic vein and is characterized by normal portal vein pressures and liver function tests. Gastrointestinal bleeding is the most common presentation and indication for treatment. Although sinistral portal hypertension-related chylous ascites is rare, several cases have described successful treatment with portal venous, rather than splenic venous, recanalization. Splenectomy is effective in the treatment of sinistral portal hypertension-related bleeding, although recent studies have evaluated splenic vein stenting and splenic arterial embolization as minimally-invasive treatment alternatives. Splenic vein stenting may be a viable option for other presentations of sinistral portal hypertension. Case Presentation: A 59-year-old gentleman with a history of necrotizing gallstone pancreatitis was referred to interventional radiology for management of recurrent chylous ascites. Analysis of ascites demonstrated a triglyceride level of 1,294 mg/dL. Computed tomography revealed splenic and superior mesenteric venous stricture. The patient elected to undergo minimally invasive transhepatic portal venography, which confirmed the presence of splenic vein and superior mesenteric vein stenosis. Venography of the splenic vein showed reversal of portal venous flow, multiple collaterals, and a pressure gradient of 14 mmHg. Two 10 mm x 40 mm Cordis stents were placed, which decreased the pressure gradient to 7 mmHg, and resolved the portosystemic collaterals. At 6 months follow-up, the patient had no recurrent episodes of ascites. Conclusion: The current case highlights successful treatment of sinistral portal hypertension-related intractable chylous ascites treated with transhepatic splenic vein stenting. Splenic venous stent patency rates of 92.9% at twelve months have been reported. Rebleeding rates of 7.1% for splenic vein stenting, 16% for splenectomy, and 47.8% for splenic arterial embolization have been reported in the treatment of sinistral portal hypertension-related gastrointestinal bleeding. The literature regarding splenic vein stenting for sinistral portal hypertension-related ascites is less robust. Technical and clinical success in the current case suggests that splenic vein recanalization may be a safe and viable option in other sinistral portal hypertension-related symptomatology.Level of Evidence: Level 4, Case Report
Path Integral Implementation of Relational Quantum Mechanics
Authors: Yang Jianhao M.
Published: February 2021

Relational formulation of quantum mechanics is based on the idea that relational properties among quantum systems, instead of the independent properties of a quantum system, are the most fundamental elements to construct quantum mechanics. In the recent works (J. M. Yang, Sci. Rep. 8:13305, 2018), basic relational quantum mechanics framework is formulated to derive quantum probability, Born's Rule, Schr\"{o}dinger Equations, and measurement theory. This paper gives a concrete implementation of the relational probability amplitude by extending the path integral formulation. The implementation not only clarifies the physical meaning of the relational probability amplitude, but also gives several important applications. For instance, the double slit experiment can be elegantly explained. A path integral representation of the reduced density matrix of the observed system can be derived. Such representation is shown valuable to describe the interaction history of the measured system and a series of measuring systems. More interestingly, it allows us to develop a method to calculate entanglement entropy based on path integral and influence functional. Criteria of entanglement is proposed based on the properties of influence functional, which may be used to determine entanglement due to interaction between a quantum system and a classical field.
Salinity Exacerbates Oil Contamination Effects in Mangroves
Authors: Naidoo Gonasageran , Naidoo Krishnaveni
Published: February 2021

The effects of salinity (10 and 50% seawater) and oil in combination on three mangroves, Avicennia marina, Bruguiera gymnorrhiza and Rhizophora mucronata were determined. In all species, plant height, number of leaves and CO2 exchange were generally higher in 10% than in 50% seawater. Salinity and oil decreased plant height, number of leaves, chlorophyll content and CO2 exchange, with reductions being greater at the higher salinity. In a second experiment, the effects of salinity (0, 10 and 50% seawater) and oil on concentrations of ions, polycyclic aromatic hydrocarbons (PAHs), leaf ultrastructure and salt secretion in A. marina were investigated. Salinity and oil in combination increased concentrations of Na+ but decreased those of K+, Ca²+ and Mg²+. PAHs damaged cell membranes, disrupted ion concentrations and reduced salt secretion. This study demonstrated that increase in salinity reduces growth of mangroves and that salinity and oiling in combination exacerbate growth reduction. In A. marina, oil was absorbed and translocated to the leaves where it disrupted membranes, ion accumulation and salt secretion.
Intraoperative Cone Beam Computed Tomography of Tracheal Stenting for Stenosis and Fistula Diseases: A Retrospective Cohort Study
Authors: Li Jing , Xu Kaihao , Han Xinwei , Li Zhaonan , Li Yahua , Zhou Xueliang , Liu Juanfang , Yao Yuan , Liu Zaoqu , Jiao Dechao
Published: February 2021

Background and objectives: Previous experience has shown that angiographic CT is useful in various medical contexts, but little research has been presented regarding the application of Cone beam Computer Tomography (CBCT) in airway stenting. In this study, we retrospectively evaluated the clinical feasibility of CBCT in airway stent placement by conducting a single-center retrospective cohort study.Methods: A total of 228 patients with stenosis or fistula diseases were treated with metallic airway stents in our hospital from January 1, 2015, to December 31, 2018. CBCT scanning was performed on 100 patients during and after treatment, and the images were compared with those from postoperative CBCT. We also assessed the outcomes and complications in the CBCT-guided and the fluoroscopy-guided group.Results: Tracheal stenting was performed successfully on the first attempt in 90 patients in the CBCT-guided group and 123 patients in the fluoroscopy-guided group. The measured diameters and lengths of the central airway as shown in CBCT were not significantly different from those obtained by MDCT. However, there were significant differences in the visibility of the distal bronchus, pulmonary parenchyma and airway above the upper stent graft; nonetheless, 2 of the 3 anatomical areas were reproduced in a diagnostically relevant way. The rate of major complications was rather low in the CBCT-guided group compared with the fluoroscopy-guided group.Conclusions: CBCT images were proven to have sufficient quality to replace MDCT as a reasonable control measure after stent implantation and reduce the complications of airway stent placement when performed in the operation.
Nutrient and Tetracycline Removal From Simulated Biogas Slurry and Biogas Upgrading by Microalgae Cultivation Under Different Carbon Nanotubes Concentration
Authors: Sun Li , Zhao Chunzhi , Sun Shiqing , Hu Changwei , Zhao Yongjun , Liu Juan
Published: February 2021

The present study aimed to determine the effects of multi-walled carbon nanotubes (MWCNTs) concentrations (0, 0.1, 1, 5, 10 mg·L− 1) on tetracycline (TC) and biogas slurry nutrients removal by microalgae Chlorella vulgaris cultivation. Treatments with 1 mg·L− 1 MWCNTs yielded maximum dry weight and cells quantity of 0.81 ± 0.008 g·L− 1 and 5.83×107 cell·L− 1, respectively. The results of chlorophyll a were consistent with rapid fluorescence induction kinetics (OJIP-test), indicating that moderate MWCNTs concentration could enhance microalgal photosynthesis. Maximum chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), tetracycline (TC), and CO2 removal efficiencies were 90.43 ± 5.15%, 78.12 ± 4.33%, 77.07 ± 4.12%, 89.64 ± 3.08%, and 64.26 ± 0.71%, respectively when treated with 1 mg·L− 1 MWCNTs. Of the five MWCNTs concentrations set in this study, the optimal concentration was 1 mg·L− 1 for nutrient and CO2 removal efficiencies. These results indicated that moderate MWCNTs concentrations would promote tetracycline and nutrients removal by enhancing Chlorella vulgaris photosynthesis activity.
Text-Independent Speaker Recognition Based on Adaptive Course Learning Loss and Deep Residual Network
Authors: Zhong Qinghua , Dai Ruining , Zhang Han , Zhu YongSheng , Zhou Guofu
Published: February 2021

Text-independent speaker recognition is widely used in identity recognition. In order to improve the features recognition ability, a method of text-independent speaker recognition based on a deep residual network model was proposed in this paper. Firstly, the original audio was extracted with a 64-dimensional log filter bank signal features. Secondly, a deep residual network was used to extract log filter bank signal features. The deep residual network was composed of a residual network and a Convolutional Attention Statistics Pooling (CASP) layer. The CASP layer could aggregate the frame-level features from the residual network into utterance-level features. Lastly, Adaptive Curriculum Learning Loss (ACLL) classifiers was used to optimize the output of abstract features by the deep residual network, and the text-independent speaker recognition was completed by ACLL classifiers. The proposed method was applied to a large VoxCeleb2 dataset for extensive text-independent speaker recognition experiments, and average equal error rate (EER) could achieve 1.76% on VoxCeleb1 test dataset, 1.91% on VoxCeleb1-E test dataset, and 3.24% on VoxCeleb1-H test dataset. Compared with related speaker recognition methods, EER was improved by 1.11% on VoxCeleb1 test dataset, 1.04% on VoxCeleb1-E test dataset, and 1.69% on VoxCeleb1-H test dataset.
Effect of B2O3 On the Microstructure and Microwave Dielectric Properties of Ba(Mg1/3Nb2/3)O3 Ceramics
Authors: Peng Sen , Yao Wenxiang , Zeng Wenfei , Xu Jianming
Published: February 2021

The influences of different doping contents of additive B2O3 on the sintering behavior, microstructure and microwave properties of Ba(Mg1/3Nb2/3)O3 (BMN) microwave ceramics were studied. The main phase in the sintered ceramics was crystallized as Ba(Mg1/3Nb2/3)O3 (BMN). Ba2B2O5 as secondary phase was observed with x ≥ 10. Scanning electron microscopy (SEM) analysis revealed that the photograph of optimally nonstoichiometric ceramics sintered at 900 ℃ for 5 h displayed a dense microstructure. The dielectric properties and microstructures of BMN ceramics were very sensitive to the nonstoichiometry. The addition of B2O3 had a positive influence on the Q×f value, for example the sample with x = 7 showed the highest Q×f value of 89800 GHz. Finally, excellent microwave dielectric properties (εr = 31.6, Q×f = 89,800 GHz and τf = 3.6 ppm/℃) were achieved for the sample with x = 7 sintered at 900 ℃ for 5 h.
The Study on the General Medical Students’ Clinical Competency in Problem Solving, Communication Skills, Procedure, History and Physical Examination and Critical and Non-Critical Indicators in Objective Structured Clinical Examination (OSCE)
Authors: Mastour Haniye , Emadzadeh Ali , Ghalibaf AmirAli Moodi
Published: February 2021

Introduction:

Clinical education is the basic pillar and heart of medical education. In fact, it is one of the most important manifestations of teaching and learning in professions related to medical sciences, which leads to the clinical competency of learners. Assessing new physicians before entering the field of clinical activities can be a reliable criterion for evaluating the quality of their clinical skills.The current study was done to investigate the knowledge, practice, and general clinical competency of general medicine graduates before entering the field of clinical activities. The study was in line with according to the document of the minimum competency expected from general practitioners in Iran.
Methods

In this descriptive cross-sectional study, the scores of different stations of the national Objective Structured Clinical Examination (OSCE), which be held at the end of the general medicine course in Iran, were collected at Mashhad University of Medical Sciences. These scores were subdivided into four specific areas and two critical and non-critical indicators of capability were gathered from the exam assessors' checklists. Totally, 266 students who participated in six periodicities of clinical competency tests at the end of the general medicine course at Mashhad University of Medical Sciences were included in the study by the census method. The clinical competency of general medicine graduates assessed in the areas of problem-solving, communication skills, practical action (procedures and critical skills), taking the history, performing physical examinations, and critical and non-critical indicators by the OSCE. Data were analyzed using descriptive statistics (frequency, mean and standard deviation) and inferential statistics including independent t-test, one-way and two-way analysis of variance by using SPSS.
Results

The results showed that the effect of different areas of the OSCE (F(3,5652) = 7.022 and P = 0.001) and participants' performance based on their critical and non-critical indicators (T = 1.976 and P = 0.04) are significant with 95% confidence interval.
Conclusion

The OSCE improves the standards of clinical competencies of new physicians and can make beneficial changes in clinical education at medical schools.
Investigation on Cu2O Combined g-C3N4/ZnO Heterostructures For High-Performance Photocatalytic Dye Degradation Under Visible-Light Exposure
Authors: Rajendran Renji , Sasireka Asokan , Priya Palanisamy , Vignesh Shanmugam , Suganthi Sanjeevamuthu , Vairamuthu Raj , Sundar Jeyaperumal Kalyana , Sriniva Manickam , Ramasamy P.
Published: February 2021

To assess a highly effective recyclable for visible-light photocatalysts (PCs), in this work, as-formed a ternary g-C3N4-ZnO/Cu2O nanocomposite PCs which was aimed at the photo-degradation of RhB dye. The essential structural, morphological and optical performance of the nanocomposites (NCs) were categorized by XRD, FT-IR, FE-SEM with EDS, UV-Vis DRS absorption and PL spectra analysis. Photocatalytic actions of the as-obtained g-C3N4-ZnO/Cu2O PCs has remained remarkably upgraded, and those showed greater degradation rate than those of other as-obtained samples. Also, that specified existence of the heterojunction among the interfaces of g-C3N4 and ZnO/Cu2O hence developed the response of visible-light absorptions and separation efficacy of the photo-excited charges which heightened the photocatalytic events of the g-C3N4-ZnO/Cu2O PCs. The photo-degradation efficiency of RhB dye over g-C3N4, g-C3N4/ZnO, g-C3N4/Cu2O and g-C3N4-ZnO/Cu2O PCs were 36.4 %, 53 % and 66 %, and 91.4 % in 100 min, which was owing to the number of dye molecules adsorbed on the PCs under visible-light treatment. The recycling stability test was exposed, the g-C3N4-ZnO/Cu2O PCs exhibit a greater photocatalytic action after five reuses. Therefore, the eco-friendly PCs might be broadly useful to the treatment of dye polluted wastewater.
Study on Water Absorptivity and Frost Resistance Performance of Self-ignition Coal Gangue Autoclaved Aerated Concrete
Authors: Cong Xinyu , Tan Yiqiu , Lu Shuang , Wang Zhaojia , Huang Tianyong
Published: February 2021

Self-ignition coal gangue (SCG) used as one of precursors to fabricate aerated autoclaved concrete (AAC). Aiming at studying water absorptivity and frost resistance performance of self-ignition coal gangue aerated autoclaved concrete (SCGAAC), three-period water absorbing tests and freezing-thawing tests were carried out and the corresponding results were recorded and analyzed. In order to modify the water absorptivity of SCGAAC, foam stabilizer was applied to adjust pore structure while calcium stearate was expected to change hydrophilic feature of CG. It was demonstrated that the compressive strength of SCGAAC containing foam stabilizer or calcium stearate declined at different levels, although the porosity became lower slightly. For water absorptivity, foam stabilizer failed to decrease the water content at any period and even increased water absorbing rates. Calcium stearate controlled water absorbing rate successfully but the ultimate water content hardly reduced. All of the SCGAAC samples exhibited intact appearance after 50 freezing-thawing cycles and showed excellent frost resistance performance. Three models were proposed to predict water absorptivity and frost resistance performance of SCGAAC and the corresponding prediction results matched test resulted well.
Terahertz Emission Increase in GaAs Films Exhibiting Structural Defects Grown on Si (100) Substrates Using a Two-Layered LTG-GaAs Buffer System
Authors: Gonzales Karl Cedric , Prieto Elizabeth Ann , Catindig Gerald Angelo , Reyes Alexander De Los , Faustino Maria Angela , Tumanguil-Quitoras Mae Agatha , Husay Horace Andrew , Vasquez John Daniel , Somintac Armando , Estacio Elmer , Salvador Arnel
Published: February 2021

Terahertz (THz) emission increase is observed for GaAs thin films that exhibit structural defects. The GaAs epilayers are grown by molecular beam epitaxy on exactly oriented Si (100) substrates at three different temperatures (Ts = 320ºC, 520ºC and 630ºC). The growth method involves the deposition of two low-temperature-grown (LTG)-GaAs buffers with subsequent in-situ thermal annealing at Ts = 600ºC. Reflection high energy electron diffraction confirms the layer-by-layer growth mode of the GaAs on Si. X-ray diffraction shows the improvement in crystallinity as growth temperature is increased. The THz time-domain spectroscopy is performed in reflection and transmission excitation geometries. At Ts = 320ºC, the low crystallinity of GaAs on Si makes it an inferior THz emitter in reflection geometry, over a GaAs grown at the same temperature on a semi-insulating GaAs substrate. However, in transmission geometry, the GaAs on Si exhibits less absorption losses. At higher Ts, the GaAs on Si thin films emerge as promising THz emitters despite the presence of antiphase boundaries and threading dislocations as identified from scanning electron microscopy and Raman spectroscopy. An intense THz emission in reflection and transmission excitation geometries is observed for the GaAs on Si grown at Ts = 520ºC, suggesting the existence of an optimal growth temperature for GaAs on Si at which the THz emission is most efficient in both excitation geometries. The results are significant in the growth design and fabrication of GaAs on Si material system intended for future THz photoconductive antenna emitter devices.
Metal Complexes of Tridentate Schiff Base: Synthesis, Characterization, Biological Activity and Molecular Docking Studies with COVID-19 Protein Receptor
Authors: Omar mohamed m , Mahmoud Walaa H. , Ahmed Yasmin mamdoh hussien , Mohamed Gehad G.
Published: February 2021

Mononuclear chelates of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II) and Cd(II) resulting from new tridentate Schiff base ligand, 4-((1-(5-acetyl-2,4-dihydroxyphenyl)ethylidene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, were synthesized and characterized via various spectroscopic methods. Metal to ligand ratio was found to be 1:1, which was revealed via elemental analysis. IR has sharp out that the coordination of the ligand towards the metal ions was carried out via NOO atoms. UV-Vis, 1HNMR spectral data, molar conductance measurements, BET surface area, melting points and theoretically through density function theory were used such as characterizing techniques in supporting of further interpretation of the complexes structures. The complexes were octahedral except Cu(II) and Ni(II) complexes were tetrahedral as suggested through the magnetic moment measurement. The complexes were found to have surface area, pore volume and particle radius 23–176 m2 g− 1, 0.02–0.33 cc/g and 8.71–4.32 nm, respectively, as pointed out from BET measurement. Schiff base ligand and its metal complexes were tested in vitro to estimate their bactericidal activity opposed to Gram-negative and Gram-positive bacteria and antifungal organisms. In the recent incident of a novel coronavirus (SARS-CoV-2) spreads, antiviral drug detection is of most importance. MOE 2008 was used headed for screen potential drugs with molecular docking by the structural protein and non-structural protein sites of new coronavirus and the study was constructed to molecular docking without validation through MD simulations. Interactions with the main protease may play a key role in fighting against viruses.
Berberine Reverses Nitroglycerin Tolerance Through Suppressing PKCα Activity in Vascular Smooth Muscle Cells
Authors: Zhang Huina , Dong Jinghui , Lau Chi-Wai , Huang Yu
Published: February 2021

Purpose
The aim of the present study was to evaluate the effects of berberine on nitroglycerin (NTG) tolerance and explore the underlying mechanism involved.
Methods
NTG tolerance was induced by pre-exposure of Sprague-Dawley rat aortas to NTG in vitro or by pretreating Sprague-Dawley rats with NTG patch in vivo. The aortas were pre-treated with berberine or PKC inhibitors for different durations of time before induction of NTG tolerance. NTG-induced vasorelaxations was measured on wire myograph. Primary vascular smooth cells (VSMCs) were used to dissect the underlying mechanism of berberine-induced inhibition of NTG tolerance.
Results
NTG tolerance induced by either prior exposure of rat aortas to NTG in vitro or pretreatment with NTG patch in vivo was reversed by co-treatment with berberine, as well as the inhibitors of PKC and PKCα. The mechanistic study revealed that PKCα participated in the development of NTG tolerance as NTG increased the activity of PKCα with enriched PKCα membrane localization and elevated phosphorylation of PKCα in VSMCs, which was reversed by berberine or PKCα inhibitors.
Conclusion
The present study is probably the first demonstration that berberine reverses NTG tolerance through inhibiting PKCα activity in VSMCs and PKCα is an important contributor to the development of NTG tolerance. These new findings suggest that berberine could become a promising drug for prevention of NTG tolerance and that targeting PKCα in VSMCs is likely to be a potential therapeutic target for reversal of NTG tolerance in blood vessels.
Solvation Free Energy Prediction from Pairwise Atomistic Interactions by Machine Learning
Authors: Lim Hyuntae , Jung YounJoon
Published: February 2021

Recent advances in machine learning technologies and their applications have led to the development of diverse structure-property relationship models for crucial chemical properties. The solvation free energy is one of them. Here, we introduce a novel ML-based solvation model, which calculates the solvation energy from pairwise atomistic interactions. The novelty of the proposed model consists of a simple architecture: two encoding functions extract atomic feature vectors from the given chemical structure, while the inner product between the two atomistic features calculates their interactions. The results of 6,493 experimental measurements achieve outstanding performance and transferability for enlarging training data owing to its solvent-non-specific nature. An analysis of the interaction map shows that our model has significant potential for producing group contributions on the solvation energy, which indicates that the model provides provides not only predictions of target properties but also more detailed physicochemical insights.
QTL mapping for Fusarium wilt resistance based on the whole-genome resequencing and their association with functional genes in Raphanus sativus
Authors: Ma Yinbo , Chhapekar Sushil Satish , Lu Lu , Yu Xiaona , Kim Seungho , Choi Gyung Ja , Lim Yong Pyo , Choi Su Ryun
Published: February 2021

Fusarium wilt is an important disease of radish, leading to severe decrease in yield and quality. In this study, we used 180 F2 populations derived from a cross between radish inbred lines ‘YR4’ and ‘YR18’ to construct linkage group for the detecting quantitative trait locus (QTLs) related to Fusarium oxysporum resistance. Four QTLs related to Fusarium oxysporum resistance were detected on two linkage groups. Of the two major loci for FW resistance, FoRsR7.1FOR59 was delimited to the 2.18-Mb physical interval on chromosome R07, with a high LOD value (5.17–12.84). Additionally, it explained 9.34%-27.97% of the phenotypic variation in three inoculation tests. The other major QTL, FoRsR9.3FOR59, was also detected in all inoculation tests, but it had a relatively low value (3.38–4.52) and explained 6.24%-8.82% of the phenotypic variation. On the basis of the re-sequencing data for the parental lines, we identified 5 R-related genes and 13 unknown genes with sequence variations at the gene and protein levels. A semi-quantitative RT-PCR analysis revealed Rs382940 (TIR-NBS type) and Rs382200 (RLK type) were expressed only in ‘YR4’ from 0 to 6 days after the inoculation. Moreover, Rs382950 (TIR-NBS-LRR type) was more highly expressed in ‘YR4’ from 3 and 6 days after the inoculation. Therefore, these three genes are likely important for the FW resistance of radish. We identified several markers based on the potential candidate genes. These gene set might be useful for breeding system to introduce the Fusarium wilt resistance loci from ‘YR4’ to improve increasing tolerance to Fusarium oxysporum.
Holling Meets Habitat Selection - Functional Response of Large Herbivores Revisited
Authors: Dupke Claudia , Peters Anne , Morellet Nicolas , Heurich Marco
Published: February 2021

Background: Holling (1959) was the first to describe a functional response between a predator’s consumption-rate and the density of its prey. The same concept may be applied to the habitat selection of herbivores, by considering the change in relative habitat use with the change in habitat availability. Functional responses in habitat selection at a home-range scale has been reported for several large herbivores. However, a link to Holling’s original functional response types has never been drawn despite its potential to understand availability dependence in habitat selection more profoundly. Methods: Discrete choice models were implemented as mixed-effects baseline-category logit models to analyze the variation in habitat selection of a large herbivore over seasonal and diurnal scales. Specifically, changes in habitat use with respect to habitat availability were investigated by monitoring 11 habitat types commonly used by roe deer ( Capreolus capreolus ) in the Bavarian Forest National Park, Germany. Functional response curves were then fitted using Holling’s formulas. Results: Strong evidence of non-linear functional responses was obtained for almost all of the examined habitat types. The shape of the functional response curves varied depending on the season, time of day and in some cases between sexes. These responses could be referenced to Holling’s types, with a predominance of type II.Conclusions: Our results indicate that Holling’s types could be applied to describe general patterns in habitat selection behaviour of herbivores. Functional response in habitat selection may occur in situations of trade-off in the selection of habitats offering different resources, due to temporally varying physiological needs of herbivores. Moreover, the two associated parameters defining the curves helps to identify the temporal variations and clarify how strongly the cost-to-benefit ratio is pronounced for a specific habitat. The presented novel approach of using Holling’s equations to describe functional response in habitat selection of herbivores could be used for assigning general habitat attraction values, independent of habitat availability, which might facilitate the identification of suitable habitats.
Physical activity in the classroom: Using RE-AIM to evaluate a national school reform – a mixed methods study
Authors: Koch Sofie , Pawlowski Charlotte Skau , Skovgaard Thomas , Pedersen Natascha Holbæk , Troelsen Jens
Published: February 2021

Background

In 2014, the Danish Government introduced a wide-ranging school reform that applied to all public schools in Denmark. A distinctive feature of the reform was that it became mandatory to implement an average of 45 minutes of daily physical activity within the curriculum. Using the RE-AIM framework as an evaluation tool, the objective of the current study was to evaluate the reach, effectiveness, adoption, implementation, and maintenance of mandatory physical activity within curriculum at ten Danish schools.
Methods

A complementary mixed methods approach using accelerometers, questionnaires, and semi-structured interviews was conducted. A total of 11 representative school were invited to participate, including 993 students, 131 teachers, and 11 school managers. Students were invited to wear an accelerometer for seven consecutive days. Teachers were invited to participate in a questionnaire and school managers were encouraged to take part in a semi-structured interview.
Results

A total of 10 schools were included in the analysis, including 846 students, 76 teachers, and 10 school managers. Results showed that, on average, 45.2% of the students were active at least 45 minutes daily within curriculum. Teacher and school management interest in physical activity, competencies development, and shared decision-making were identified as central factors for adoption of the requirement. Scheduling physical activity within timetables and collaborations with external parties were found to influence the implementation dimension. Finally, internal coordination, motivated school staff, and school management priority were identified as centrals factors for maintenance.
Conclusions

This study provides an evaluation on a national physical activity requirement in Danish public schools. When introcuding a wide-ranging national requirement on physical activity within curriculum, school managers need to prioritize and support the implementation process. Teachers need to be involved in the decision processes, in order to ensure motivation and local ownership. The study also highlight the benefits of an internal coordinator as well as development of a shared strategy among schools, municipalities, and other stakeholders in order to succeed with the implementation.
Association between Periodontal Status and Degree of Maxillary Sinus Mucosal Thickening: a Retrospective CBCT Study
Authors: Zhang Tianyi , He Zhengquan , Tian Huan
Published: February 2021

Background: It is well known that periodontitis can stimulate thickening of the maxillary sinus mucosa, but the association between periodontitis status and the degree of maxillary sinus mucosal thickening (maxMT) has not been reported. The objectives of this study were to investigate the effect of periodontal status of maxillary molars on the degree of maxMT. Methods: Retrospective analysis of cone-beam computed tomographic (CBCT) images of 203 periodontitis cases with maxMT. Parameters related to periodontitis in maxillary molars were measured and recorded on CBCT images. The dimension and length of the maxMT were also recorded. Multiple linear regression analysis was used to identify periodontal factors influencing the severity of maxMT, and multivariate logistic regression analysis was used to identify the odds ratio(OR) of these factors. Results: The factors affecting the degree of maxMT were mainly the amount of alveolar bone loss(ABL) and the minimum residual alveolar bone height (miniRABH). Compared to mild ABL, severe and moderate ABL were more likely to display severe maxMT. And the lower the miniRABH , the more severe the maxMT. Conclusions: The severity of periodontal status of maxillary molars can influence the degree of maxMT.
In Vivo Evaluation of a Recombinant N-acylhomoserine Lactonase Formulated in a Hydrogel Using a Murine Model Infected With Mdr Pseudomonas Aeruginosa Clinical Isolate, CCASUP2
Authors: Sakr Masarra M. , Elkhatib Walid F. , Aboshanab Khaled , Mantawy Eman M. , Yassien Mahmoud A. , Hassouna Nadia A.
Published: February 2021

Failure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections.
Comparing RNA extraction methods to face the variations in RNA quality using two human biological matrices.
Authors: Ortega-Pinazo Jesús , Serrano-Castro Pedro Jesús , Vida-Botella Margarita , Martínez Beatriz , Pinto-Medel María Jesús , Oliver-Martos Begoña , Leyva Laura , Gómez-Zumaquero Juan Miguel , Lago-Sampedro Ana , Rodríguez-Bada Pablo Jesús , Estivill-Torrús Guillermo , Ferro Pedro
Published: February 2021

Nucleic acids, RNA among them, are widely used in biomedicine. Because of its susceptibility to degradation by RNases, the handling and extraction process of RNA from cells and tissues require specialized personnel and standardized methods to guarantee high purity and integrity. Due to the diversity of techniques found in the market, a comparative study between different RNA extraction methods is useful to facilitate the best choice for the researcher. In this study, we have compared seven different RNA extraction methods (automated, semi-automated, and manual) from two biological matrices: human Jurkat T cells and peripheral blood mononuclear cells (PBMC). Results showed marked differences in the RNA quality, and functionality according to the method employed for RNA extraction and the matrix used. These data contribute to facilitate researchers in decision-making practices and emphasize the relevance of the selection of the RNA extraction method in each experimental procedure to guarantee both quality standards and its reproducibility.
Antiferromagnetic Skyrmion Crystals in the Rashba Hund’s Model on Triangular Lattice
Authors: Mukherjee Arnob , Kathyat Deepak Singh , Kumar Sanjeev
Published: February 2021

Motivated by the importance of antiferromagnetic skyrmions as building blocks of next-generation data storage and processing devices, we report theoretical and computational analysis of a model for a spin-orbit coupled correlated magnet on a triangular lattice. We find that two distinct antiferromagnetic skyrmion crystal (AF-SkX) states can be stabilized at low temperatures in the presence of external magnetic field. The results are obtained via Monte Carlo simulations on an effective magnetic model derived from the microscopic electronic Hamiltonian consisting of Rashba spin-orbit coupling, as well as the Hund’s rule coupling of electrons to large classical spins. The two AF-SkX phases are understood to originate from a classical spin liquid state that exists at low but finite temperatures. These AF-SkX states can be easily distinguished from each other in experiments as they are characterized by peaks at distinct momenta in the spin structure factor which is directly measured in neutron scattering experiments. We also discuss examples of materials where the model as well as the two AF-SkX states can be realized.
Functional and diffusion MRI reveal the functional and structural basis of infants’ noxious-evoked brain activity
Authors: Baxter Luke , Moultrie Fiona , Fitzgibbon Sean , Aspbury Marianne , Mansfield Roshni , Bastiani Matteo , Rogers Richard , Jbabdi Saad , Duff Eugene , Slater Rebeccah
Published: February 2021

Understanding the neurophysiology underlying neonatal responses to noxious stimulation is central to improving early life pain management. In this neonatal multimodal MRI study, we use resting-state and diffusion MRI to investigate inter-individual variability in noxious-evoked brain activity. We demonstrate that cerebral haemodynamic responses to experimental noxious stimulation can be predicted from separately acquired resting-state brain activity (n=18). Applying this prediction model to independent Developing Human Connectome Project data (n=215), we identify negative associations between predicted noxious-evoked responses and white matter mean diffusivity. These associations are subsequently confirmed in the original noxious stimulation paradigm dataset, validating the prediction model. This study in healthy neonates demonstrates that noxious-evoked brain activity is tightly coupled to both resting-state activity and white matter microstructure, that neural features can be used to predict responses to noxious stimulation, and that the dHCP dataset could be utilised for future exploratory research of early life pain system neurophysiology.