检索结果-南通市图书馆

A study of the Comets with large Perihelion Distances C/2019 l3(ATlAs)and C/2019 O3(Palomar)

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第9期24卷 199-213页

作者： Alberto s.Betzler Centro de Ciencia e Tecnologia em Energia e sustentabilidade Universidade Federal do Recôncavo da BahiaFeira de SantanaBahia44.085-132Brazil

This work analyzes the photometric data of the Oort spike comets C/2019 l3(ATlAs)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATlAs network and the Belgian Olmen *** comets Palomar and ATlAs have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at *** absolute magnitude of comets ATlAs and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 *** cometary activity of comets ATlAs and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of *** nucleus of comet ATlAs has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little *** c-o colors of the comets ATlAs and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP *** comets showed a bluish trend in the coma color with decreasing heliocentric *** Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of *** slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign.

关键词： individual C/2019 l3(ATlAs) C/2019 O3(Palomar) techniques:photometric methods:data analysis

Missed Pancreaticobiliary Malignancy: The Flaw of the Expedited Cholecystectomy

在线全文

学校读者我要写书评

暂无评论

surgical science 2024年第7期15卷 451-464页

作者： Dylan s. Goto larissa Fujii-lau linda l. Wong Department of surgery John A. Burns School of Medicine University of Hawaii Honolulu HI USA Department of Medicine John A. Burns School of Medicine University of Hawaii Honolulu HI USA

Background: Early cholecystectomy has been recommended for patients with acute cholecystitis and gallstone pancreatitis. However, patients with pancreaticobiliary malignancy may present acutely with similar symptoms. We hypothesize that the diagnoses of these malignancies may potentially be delayed as an unintended consequence of expedited cholecystectomies. This study reviews a cohort of patients who underwent pancreaticoduodenectomy (PD) to identify those who underwent a separate cholecystectomy before their PD. Methods: We retrospectively reviewed 162 PDs performed between 2012 and 2022. Data collected included: demographics, disease etiology and the presence of cholelithiasis. We identified patients who had a previous cholecystectomy and the time elapsed before PD as well as procedures done during the interval. We reported detailed case summaries on those patients who had a cholecystectomy within 1 year of PD. Results: In the entire cohort, mean age was 65 years, 54% were males, and 83% had a malignant reason for PD. Thirty-one patients had cholelithiasis with 23 (14%) patients having had previous cholecystectomy. six patients had cholecystectomy within 1 year of PD. They had the following malignancies: ampullary—3, pancreas—1, cholangiocarcinoma—1 and neuroendocrine—1. Four of these patients had expedited cholecystectomy on their index hospital admission and were later found to have a periampullary malignancy with further work up. Conclusions: Pancreaticobiliary malignancies can be difficult to diagnose, and surgeons should not overlook these potential diagnoses when considering expedited cholecystectomy. Future studies in large cohorts are needed to identify high risk candidates who should undergo more detailed testing to exclude malignancy before proceeding with cholecystectomy.

关键词： Cholecystectomy Periampullary Malignancy Pancreas Malignancy Pancreaticoduodenectomy

Why sustainable Porous Carbon should be Further Explored as Radar-Absorbing Material? A Comparative study with Different Nanostructured Carbons

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2024年第10期12卷 1639-1659页

作者： Alan F.N.Boss Manuella G.C.Munhoz Gisele Amaral-labat Rodrigo G.A.lima leonardo I.Medeiros Nila C.F.l.Medeiros Beatriz C.s.Fonseca Flavia l.Braghiroli Guilherme F.B.lenz e silva Department of Metallurgical and Materials Engineering University of de São PauloAvenida Mello MoraesCidade UniversitáriaSão PauloSP 05508-030Brazil Coordination of Applied Research and Technological Development National Institute for Space ResearchAvenida dos AstronautasJardim da GranjaSão Josédos CamposSP 12227-010Brazil Department of Exact and Technological sciences Santa Cruz State UniversityRodovia Jorge Amadokm16IlhéusBA 45662900Brazil Institut de recherche sur les forêts Universitédu Québec en Abitibi-TémiscamingueRouyn-Noranda445 Bd de l’UniversitéRouyn-NorandaQC J9X 5E4Canada

Radar Absorbing Materials(RAM)are a class of composites that can attenuate incident electromagnetic waves to avoid radar *** carbon allotropes that have the potential to be used as RAM are either carbon nano-tubes(CNTs),graphene,carbon black(CB)and ultimately,sustainable porous carbon(sPC).Here,black wattle bark waste(following tannin extraction)was used as a sustainable source to produce sPC made from biomass *** was characterized and used as aﬁller for a silicone rubber matrix to produce aﬂexible *** elec-tromagnetic performance of this composite was compared with composites made with commercial CB and CNT through reﬂection loss(Rl),where-10 dB is equivalent to 90%of *** composites were evaluated in single-layer,double-layer,and as radar absorbing structures(RAs)with the aim of improving their effective absorption bandwidth(EAB)performances and a reduction in *** CNT composite presented a Rl of-26.85 dB at 10.89 GHz and an EAB of 2.6 GHz with a 1.9 mm thickness,while the double-layer structures using CNT and sPC provided a Rl of-19.74 dB at 10.75 GHz and an EAB of 2.51 ***,the double-layer structures are~42%cheaper than the composite using only CNT since less material is ***,the largest EAB was achieved with a RAs using sPC,reaching~2.8 GHz and a Rl of-49.09 dB at 10.4 ***,sPC made of black wattle bark waste can be a competitive,alternative material for use as RAM and RAs since it is cheaper,sustainable,and suitable for daily life uses such as absorbers for anechoic chambers,sensors,and elec-tromagnetic interference shields for electronics,wallets,vehicles,and others.

关键词： Microwave absorption material tannin waste dielectric constant carbon composite reﬂectivity

Monte Carlo simulations of Doping Properties of a spin-3/2 Ising Nanotube

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Condensed Matter Physics 2024年第3期14卷 51-65页

作者： sènan Ida Valérie Hontinfinde Noèl Odjo Joèl Kple Ansèlme Kpadonou Félix Hontinfinde Ecole Nationale suprieure de Gnie Mathmatique et Modlisation (ENsGMM) UNSTIM Abomey Benin Facult des sciences et Techniques Universit dAbomey-Calavi Abomey-Calavi Benin Institut de Mathmatique et de sciences Physiques Universit dAbomey-Calavi Abomey-Calavi Benin Ecole Normale suprieure UNSTIM Natitingou Benin

The effect of spin-1 impurities doping on the magnetic properties of a spin-3/2 Ising nanotube is investigated using Monte Carlo simulations within the Blume-Emery-Griffiths model in the presence of an external magnetic field. The thermal behaviors of the order parameters and different macroscopic instabilities as well as the hysteretic behavior of the material are examined in great detail as a function of the dopant density. It is found that the impurities concentration affects all the system magnetic properties generating for some specific values, compensation points and multi-cycle hysteresis. Doping conditions where the saturation/remanent magnetization and coercive field of the investigated material can be modified for permanent or soft magnets synthesis purpose are discussed.

关键词： Doped Ising Nanotube Monte Carlo simulations Compensation Point Phase Transitions Coercive Field

simultaneous removal of critical rare earth elements and chalcogen oxyanions by anaerobic granular sludge

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第9期43卷 4595-4611页

作者： Chiara Belloni Mohanakrishnan logan stefano Papirio Piet N.l.lens University of Galway Galway H91 TK33Ireland Department of Civil Architectural and Environmental EngineeringUniversity of Naples Federico II80125 NaplesItaly

Conventional mining of economically and strategically important critical rare earth elements(REEs)(such as neodymium,lanthanum and dysprosium),and chalcogens(such as selenium and tellurium)are associated with a huge economic and environmental ***,the need to recover REEs as well as chalcogens from different waste streams including wastewaters is becoming *** assays on synthetic chalcogen/REE-laden wastewater showed that the presence of REEs significantly improved the tellurite removal rate(>80%)and enhanced selenate removal by 66%±10%.Three 3.9 l continuous upflow anaerobic granular sludge bed(UAsB)reactors were operated at a hydraulic retention time of 24 h and 30℃.selenate reduction was achieved with a removal efficiency of~98% with an influent p H of 4.0 for more than 28 *** effect of REEs on tellurite removal in the UAsB bioreactor could not be clearly established since a soluble tellurium removal efficiency of more than 98%was observed already before the addition of REEs at elevated tellurite *** complete REE removal in both batch assays and UAsB reactors at higher pH(7.0±0.5)was attributed to precipitation,whereas chalcogen oxyanions removal was due to microbial ***,at acidic p H,biosorption was responsible for REE's removal,and the se-enriched sludge exhibited a superior REE's removal efficiency than the non-enriched and Te-enriched sludge.

关键词： Rare earth elements selenium Tellurium Bioreduction Adsorption

Neuroprotective effects of G9a inhibition through modulation of peroxisome-proliferator activator receptor gamma-dependent pathways by miR-128

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第11期19卷 2532-2542页

作者： Aina Bellver-sanchis Pedro AAvila-lópez Iva Tic David Valle-García Marta Ribalta-Vilella luis labrador Deb Ranjan Banerjee Ana Guerrero Gemma Casadesus Coralie Poulard Mercè Pallàs Christian Grinán-Ferré Department of Pharmacology and Therapeutic Chemistry Institut de Neurociències-Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Molecular Genetics Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Institute of Biotechnology National Autonomous University of MexicoCuernavacaMexico Department of Pharmacology and Therapeutics Health Science Center-University of FloridaGainesvilleFLUSA Department of Chemistry National Institute of Technology DurgapurM G AvenueDurgapurWest BengalIndia Cancer Research Cancer lyon Universitéde LyonLyonFrance Inserm U1052 Centre de Recherche en Cancérologie de LyonLyonFrance CNRs UMR5286 Centre de Recherche en Cancérlogie de LyonLyonFrance Centro de Investigación en Red Enfermedades Neurodegenerativas(CIBERNED)Instituto de Salud Carlos IIIMadridSpain Neuroimmunology Department National Institute of Neurology and Neurosurgery“Manuel Velasco Suárez”Mexico CityMexico

Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative ***,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s ***,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and *** better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(sAMP8)control mice and sAMP8 treated with G9a inhibitor *** found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)***,Pparg gene expression levels were higher in the sAMP8 group treated with G9a inhibitor than in the sAMP8 control *** also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a *** confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative *** this setting,treatment with G9a inhibitor increases both cell survival and antioxidant ***,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and *** addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers ***,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a ***,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.

关键词： aging cognitive decline epigenetics G9a inhibition microRNAs miR-128 peroxisome-proliferator activator receptorγ(PPARγ) PPARG sAMP8

Optimizing Average Electric Power During the Charging of lithium-Ion Batteries Through the Taguchi Method

在线全文

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2024年第2期30卷 152-166页

作者： Mohd H.s.Alrashdan Department of Electrical Engineering Al-Hussein Bin Talal UniversityMaan 71110Jordan

In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17

关键词： lithium-ion batteries Average electric power during charging Taguchi method COMsOl Multiphysics software C rate l27 orthogonal array

The flattening of spacetime hierarchy of the N,N-dimethyltryptamine brain state is characterized by harmonic decomposition of spacetime(HADEs) framework

在线全文

学校读者我要写书评

暂无评论

National science Review 2024年第5期11卷 46-55页

作者： Jakub Vohryzek Joana Cabral Christopher Timmermann selen Atasoy leor Roseman David J.Nutt Robin l.Carhart-Harris Gustavo Deco Morten l.Kringelbach Centre for Eudaimonia and Human Flourishing Linacre CollegeDepartment of Psychiatry University of Oxford Department of Psychiatry University of Oxford Center for Music in the Brain Aarhus University Center for Brain and Cognition Computational Neuroscience GroupDepartment of Information and Communication TechnologiesUniversitat Pompeu Fabra life and Health sciences Research Institute School of MedicineUniversity of Minho ICVs/3B's-PT Government Associate laboratory Centre for Psychedelic Research Department of Brain Sciences Imperial College London Departments of Neurology and Psychiatry University of California San Francisco Institució Catalana de la Recerca i Estudis Avan?ats (ICREA) Department of Neuropsychology Max Planck Institute for Human Cognitive and Brain Sciences school of Psychological sciences Monash University

The human brain is a complex system, whose activity exhibits flexible and continuous reorganization across space and time. The decomposition of whole-brain recordings into harmonic modes has revealed a repertoire of gradient-like activity patterns associated with distinct brain functions. However, the way these activity patterns are expressed over time with their changes in various brain states remains unclear. Here, we investigate healthy participants taking the serotonergic psychedelic N,N-dimethyltryptamine(DMT) with the Harmonic Decomposition of spacetime(HADEs) framework that can characterize how different harmonic modes defined in space are expressed over time. HADEs demonstrates significant decreases in contributions across most low-frequency harmonic modes in the DMT-induced brain state. When normalizing the contributions by condition(DMT and non-DMT), we detect a decrease specifically in the second functional harmonic, which represents the uni-to transmodal functional hierarchy of the brain,supporting the leading hypothesis that functional hierarchy is changed in psychedelics. Moreover, HADEs'dynamic spacetime measures of fractional occupancy, life time and latent space provide a precise description of the significant changes of the spacetime hierarchical organization of brain activity in the psychedelic state.

关键词： spatio-temporal brain dynamics DMT harmonic modes

Explainable Conformer Network for Detection of COVID-19 Pneumonia from Chest CT scan: From Concepts toward Clinical Explainability

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 1171-1187页

作者： Mohamed Abdel-Basset Hossam Hawash Mohamed Abouhawwash s.s.Askar Alshaimaa A.Tantawy Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of statistics and Operations Research College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

The early implementation of treatment therapies necessitates the swift and precise identification of COVID-19 pneumonia by the analysis of chest CT *** study aims to investigate the indispensable need for precise and interpretable diagnostic tools for improving clinical decision-making for COVID-19 *** paper proposes a novel deep learning approach,called Conformer Network,for explainable discrimination of viral pneumonia depending on the lung Region of Infections(ROI)within a single modality radiographic CT ***,an efficient U-shaped transformer network is integrated for lung image ***,a robust transfer learning technique is introduced to design a robust feature extractor based on pre-trained lightweight Big Transfer(BiT-l)and finetuned on medical data to effectively learn the patterns of infection in the input ***,this work presents a visual explanation method to guarantee clinical explainability for decisions made by Conformer *** evaluation of real-world CT data demonstrated that the diagnostic accuracy of ourmodel outperforms cutting-edge studies with statistical *** Conformer Network achieves 97.40% of detection accuracy under cross-validation *** model not only achieves high sensitivity and specificity but also affords visualizations of salient features contributing to each classification decision,enhancing the overall transparency and trustworthiness of our *** findings provide obvious implications for the ability of our model to empower clinical staff by generating transparent intuitions about the features driving diagnostic decisions.

关键词： Deep learning COVID-19 multi-modal medical image fusion diagnostic image fusion