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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese physics B 2024年第2期33卷 108-114页

作者： U.S.Mahabaleshwar G.p.Vanitha L.M.pérez Emad h.Aly I.pop Department of Studies in Mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in h_(2)O past a stretched/shrinked sheet.With the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is illustrated.The resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity transformations.The transformed differential equations are solved analytically.Impacts of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted graphically.The skin friction and Nusselt number were also evaluated.In addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching one.Further,Al_(2)O_(3)/h_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/h_(2)O nanofluid.Furthermore,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

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Marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.p.Nagahawatta N.M.Liyanage Thilina U.Jayawardena h.h.A.C.K.Jayawardhana Seong‑hun Jeong hyung‑Jun Kwon You‑Jin Jeon Department of Marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ferocity.SARS-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World health Organization.Therefore,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently required.Numerous naturally occurring bioactive substances have been studied in the clinical setting for diverse disorders.The intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic compounds.Marine natural products(MNps)have received increased attention in the development of novel drugs owing to their high diversity and availability.Therefore,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and structure.Furthermore,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing MNps and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 Marine natural products Drug targets Inhibitors

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd3+-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257页

作者： C.Y.Morassuti A.p.L Silva L.A.O.Nunes S.M.Lima L.h.C.Andrade Optical and photothermal Spectroscopy Group (GEOF) Center for Studies in Natural Resources (CERNA)State University of Mato Grosso do Sul(UEMS) Renato Archer Information Technology Center Institute of physics of Sao Carlos University of S?o Paulo

Nd3+-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio（FIR） technique.Nevertheless,at high Nd3+concentrations,energy transfer（ET） processes such as optical reabsorption and cross-relaxation can affect the Nd3+emission,which has been little explored in the literature.Therefore,the present work investigated the use of Nd3+-doped tellurite glass(samples doped with Nd3+at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%) in fluorescence thermometers,in the temperature range from 299 to 371 K.The results indicate a strong dependence of the FIR parameters on the Nd3+concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd3+emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio4F5/2→4I9/2/4F3/2→4I9/2is observed for samples doped with higher amounts of Nd3+.The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd3+ions.

关键词： Fluorescence intensity ratio Judd-Ofelt Nd3+-doped tellurite glass Optical thermometry Rare earths

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu S.M.Weng p.Li X.F.Li h.Ai h.R.pan Z.M.Sheng Key Laboratory for Laser plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering physics MianyangSichuan 621900China State key Laboratory of high Field Laser physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and medicine.Besides conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz pulses.here,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long wavelength.The signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver pulse.Owing to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake bubble.Consequently,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer wavelengths.This greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

CD8+T cell metabolic flexibility elicited by CD28-ARS2 axisdriven alternative splicing of pKM supports antitumor immunity

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Cellular & Molecular Immunology 2024年第3期21卷 260-274页

作者： G.Aaron holling Colin A.Chavel Anand p.Sharda Mackenzie M.Lieberman Caitlin M.James Shivana M.Lightman Jason h.Tong Guanxi Qiao Tiffany R.Emmons Thejaswini Giridharan Shengqi hou Andrew M.Intlekofer Richard M.higashi Teresa W.M.Fan Andrew N.Lane Kevin h.Eng Brahm h.Segal Elizabeth A.Repasky Kelvin p.Lee Scott h.Olejniczak Department of Immunology Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Department of Medicine Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA human Oncology and pathogenesis program Memorial Sloan Kettering Cancer CenterNew YorkNY 10065USA Center for Environmental Systems Biochemistry Department of Toxicology and Cancer Biology and Markey Cancer CenterLexingtonKY 40536USA Department of Cancer Genetics and Genomics Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA present address:University of Colorado Boulder BoulderCO 80309USA present address:Dana Farber Cancer Institute BostonMA 02215USA present address:Massachusetts Institute of Technology BostonMA 02139USA present address:Melvin and Bren Simon Comprehensive Cancer Center Indiana University School of MedicineIndianapolisIN 46202USA

Metabolic flexibility has emerged as a critical determinant of CD8+T-cell antitumor activity,yet the mechanisms driving the metabolic flexibility of T cells have not been determined.In this study,we investigated the influence of the nuclear cap-binding complex(CBC)adaptor protein ARS2 on mature T cells.In doing so,we discovered a novel signaling axis that endows activated CD8+T cells with flexibility of glucose catabolism.ARS2 upregulation driven by CD28 signaling reinforced splicing factor recruitment to pre-mRNAs and affected approximately one-third of T-cell activation-induced alternative splicing events.Among these effects,the CD28-ARS2 axis suppressed the expression of the M1 isoform of pyruvate kinase in favor of pKM2,a key determinant of CD8+T-cell glucose utilization,interferon gamma production,and antitumor effector function.Importantly,pKM alternative splicing occurred independently of CD28-driven pI3K pathway activation,revealing a novel means by which costimulation reprograms glucose metabolism in CD8+T cells.

关键词： Immunometabolism mRNA splicing CD8 T cells ARS2 pKM2

A novel diurnal and seasonal variation analysis of BTEX in Bengaluru urban area

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Research in Cold and Arid Regions 2024年第1期16卷 14-19页

作者： h.N.Sowmya M.Dinamani G.p.Shivashankara h.K.Ramaraju B.S.Surendra Vijaya V.Shanbhag R.prajwal Department of Civil Engineering Dayananda Sagar College of EngineeringBangalore 560078India Department of Chemistry Dayananda Sagar College of EngineeringBangalore 560078India Department of physics GFGCVijayanagarBengaluru 560040India

In the urban atmosphere of Bengaluru, various volatile organic compounds(VOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the Bengaluru Metropolitan City. hourly sample data was collected using a BTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. Benzene levels were lowest during the early morning hours, specifically from 1:00 a.***.to 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. however, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of Benzene, EthylBenzene, and Mp-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of BTEX compounds. Conversely, lower BTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among BTEX parameters strongly suggests a common source, most likely originating from vehicular emissions.

关键词： BTEX Summer variation Meteorological parameters Correlation

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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Journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu G.G.Wang A.hu Y.Li K.B.Thacker J.p.Weiler h.hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada Global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important issue.But,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die casters.The aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process parameters.The Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn ratio.The design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding time.The sludge yield(SY)and intermetallic size(IS)was selected as two responses.The optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,respectively.The best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,respectively.Three groups of sludge factors,Chemical Sludge(CSF),physical Sludge(pSF)and Comprehensive Sludge Factors(and CpSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg alloys.The CpSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the pSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental data.The Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed easily.The physical Sludge Factor could be used for mass production with a single type of Mg allo

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition process parameter

Effect of mitomycin C on the corneal endothelial cells of Saudi patients with myopia after transepithelial photorefractive keratectomy:a two-armed cohort study

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 909-915页

作者： Sultan h Alrashidi Department of Ophthalmology College of MedicineQassim UniversityBuraidah 51452Saudi Arabia

AIM:To study the effect of mitomycin C(MMC)applied during transepithelial photorefractive keratectomy(TpRK)on the corneal endothelium one week(W1)and three months(M3)after surgery and its determinants.METhODS:In this two-armed cohort study conducted in 2022,eyes treated with MMC during TpRK(group 1)were compared with eyes not treated with MMC(group 2).The corneal endothelial cell(EC)count,EC density(ECD;cells/mm2),average(μm2),standard deviation(μm2),coefficient of variation(CV%),ECmax,ECmin,and EC percentage of hexagonality were estimated at W1 and M3.The postoperative changes in the EC count in the two groups were compared and correlated with the other independent variables.RESULTS:Group 1 had 26 eyes,and group 2 had 78 eyes.All TpRK indices were significantly higher for the eyes in group 1 than for those in group 2.The MMC usage was not a significant predictor of the change in ECD(p=0.644),change in CV(p=0.374),and change in the percentage of hexagonality of EC(p=0.164)at W1.however,the use of MMC was a significant predictor of changes in CV(p=0.014)and the change in the percentage of hexagonality of EC(p=0.039)at M3.The duration of laser exposure and the size of the optical zone influenced the correlation of MMC use with the changes in EC indices,postoperatively.CONCLUSION:The use of MMC doesn’t affect ECD,CV,and percentage of hexagonality at W1 if other surgical indices are considered.At M3 after operating myopic eyes by TpRK,MMC significantly influence the CV and percentage of hexagonality.The duration of the laser application and the size of the optical zone should be considered when determining the effect of MMC on the EC indices.

关键词： transepithelial photorefractive keratectomy mitomycin-C corneal endothelium

Anti-obesity effects of fucoidan from Sargassum thunbergii in adipocytes and high fat diet induced obese mice through inhibiting adipogenic specific transcription factor

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Food Science and human Wellness 2024年第3期13卷 1608-1616页

作者： hyo-Geun Lee h.h.A.C.K.Jayawardhana Fengqi Yang D.p.Nagahawaththa N.M.Liyanage Kyung-Mo Song Yun-Sang Choi Seung-hong Lee You-Jin Jeon Min-Cheol Kang Department of Marine Life Sciences Jeju National UniversityJeju 63243Republic of Korea Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Research Group of Food processing Korea Food Research InstituteWanju 55365Republic of Korea Department of pharmoceutical Engineering Soonchunhyang UniversityAsan 31538Republic of Korea

The prevalence of obesity has increased and is a health concern worldwide.Due to the concerns regarding synthetic anti-obesity treatments,nowadays natural products become a trend.previous studies proved that there is a potential to use marine algae as anti-obesity agents.Therefore,in this study,the lipid inhibitory effect of crude polysaccharide of amyloglucosidase-assisted hydrolysate from Sargassum thunbergii(STAC)and its fucoidan fractions(STAFs)on 3T3-L1 cells and high-fat diet(hFD)-induced obese mice were investigated.According to the results,the STAF3,showed the highest xylose content and exhibited significant inhibitory effects on lipid accumulation by downregulating adipogenic and lipogenic proteins in 3T3-L1 cells.Furthermore,oral supplementation with STAC significantly declined gain in body weight and fat weight,and serum lipid contents in an hFD-induced obesity mouse model.Structural and chemical characterizations demonstrated that puritied STAF3 has consistent surface morphology and small particle size,with similar structural characteristics as commercial fucoidan.Together,these results indicate that STAC and purified STAF3 from Sargassum thunbergia is a potent source to develop as ananti-obesity agents or functional food products to counter obesity.

关键词： Sargassum thunbergii Fucoidan Anti-obesity Anti-steatosis