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Theoretical study of differential cross sections for the ionization of helium by fast proton impact

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Chinese Physics B 2024年第11期33卷 255-264页

作者： M Mondal B Mandal T Mistry d.jana M Purkait department of Physics Ramakrishna Mission Residential CollegeNarendrapurKolkata-700103India

We present the angular distribution of the ejected electron for single ionization of He by fast proton impact.A fourbody formalism of the three-Coulomb wave is applied to calculate the triple differential cross sections at several impact energies in the scattering,perpendicular and azimuthal ***,the three-body formalism of three-Coulomb,two-Coulomb and first Born approximation models has also been used to study the many-body effect on electron emission and the validity of the *** the three-Coulomb wave model,the final state wave function incorporates distortion due to the three-body mutual Coulombic *** this formalism,we use an uncorrelated and correlated Born initial state,which consists of a plane wave for the incoming projectile times a two-electron bound state wavefunction of the helium atom representing the 1s2(1S)***,in the case of the three-body formalism,the initial state wavefunction consists of a long-range Coulomb distortion for the incoming projectile and one active electron of the He atom described by the Roothaan–Hartree–Fock *** structure with a single or two peaks with unequal intensity is observed in the angular distributions of the triple differential cross sections for the different kinematic *** addition,the influence of static electron correlations is investigated using different bound state wavefunctions for the ground state of the He *** the four-body formalism,the present computations are very fast by reducing a nine-dimensional integral to a two-dimensional real *** the simplicity and speed of the proposed quadrature,the comparison shows that the obtained results are in reasonable agreement with the experiment and are compatible with those of other theories.

关键词： ionization cross sections collision atoms ions

Entropy analysis of unsteady magneto-nanofluid flow past accelerating stretching sheet with convective boundary condition

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Applied Mathematics and Mechanics(English Edition) 2015年第12期36卷 1593-1610页

作者： S.dAS S.CHAKRABORTY R.N.jana O.d.MAKINdE department of Mathematics University of Gour Banga department of Applied Mathematics Vidyasagar University Faculty of Military Science Stellenbosch University

The unsteady laminar magnetohydrodynamics （MHd） boundary layer flow and heat transfer of nanofluids over an accelerating convectively heated stretching sheet are numerically studied in the presence of a transverse magnetic field with heat source/sink The unsteady governing equations are solved by a shooting method with the Runge-Kutta- Fehlberg scheme. Three different types of water based nanofluids, containing copper, aluminium oxide, and titanium dioxide, are taken into consideration. The effects of the pertinent parameters on the fluid velocity, the temperature, the entropy generation num- ber, the Bejan number, the shear stress, and the heat transfer rate at the sheet surface are graphically and quantitatively discussed in detail. A comparison of the entropy generation due to the heat transfer and the fluid friction is made with the help of the Bejan number. It is observed that the presence of the metallic nanoparticles creates more entropy in the nanofluid flow than in the regular fluid flow.

关键词： unsteady MHd flow nanofluid heat source/sink entropy generation Bejan number

Changes of the liver metabolome following an intravenous lipopolysaccharide injection in Holstein cows supplemented with dietary carnitine

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Journal of Animal Science and Biotechnology 2023年第1期14卷 188-199页

作者： Wei Xu Sandra Grindler Akos Kenez Sven danicke jana Frahm Korinna Huber Beijing Research Center of Intelligent Equipment for Agriculture Beijing 100097China. department of Biosystems Biosystems Technology ClusterCampus GeelKleinhoefstraat 42440 Geel LeuvenKUBelgium. Institute of Animal Science Faculty of Agricultural SciencesUniversity of Hohenheim70599 StuttgartGermany. department of Infectious diseases and Public Health City University of Hong KongBlock 14/FTo Yuen Building31 To Yuen StreetKowloonHong Kong SARChina. Institute of Animal Nutrition Federal Research Institute for Animal Health(Friedrich-Loeffler-Institut)38116 BrunswickGermany.

Background:Carnitine facilitates the flux of long-chain fatty acids for hepatic mitochondrial beta-oxidation,which acts to ameliorate the negative energy balance commonly affecting high-yielding dairy *** triggered by lipopolysaccharide(LPS)load can however pose a challenge to the metabolic integrity via the expression of pro-inflammatory mediators,leading to immune system activation and respective metabolic *** effect of enhanced carnitine availability on hepatic metabolome profiles during an inflammatory challenge has not yet been determined in dairy ***,Holstein cows were supplemented with 25 g/d rumen-protected carnitine from 42d prepartum until 126 d postpartum(n=16)or assigned to the control group with no supplementation during the same period(n=14).We biopsied the liver of the cows before(100 d postpartum)and after(112 d postpartum)an intravenous injection of 0.5μg/kg *** samples were subjected to a targeted metabolomics analysis using the AbsoluteIdQ p180 Kit(Biocrates Life Sciences AG,Innsbruck,Austria).Results:Multivariate statistical analyses revealed that hepatic metabolome profiles changed in relation to both the carnitine supplementation and the LPS *** the metabolite profiles on 100 d,carnitine increased the concentration of short-and long-chain acyl-carnitines,which may be explained by an enhanced mitochondrial fatty acid shuttle and hence greater energy *** LPS injection affected hepatic metabolite profiles only in the carnitine supplemented group,particularly altering the concentration of biogenic ***:Our results point to interactions between an acute hepatic inflammatory response and biogenic amine metabolism,depending on energy availability.

关键词： Acyl-carnitines Inflammatory response Lipid metabolism Liver metabolome Mitochondrial function

Effect of storage conditions on long-term stability of Ag nanoparticles formed via green synthesis

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1177-1182页

作者： Oksana Velgosova Elena Cizmarova Jaroslav Málek jana Kavulicova Institute of Materials Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia department of Materials Engineering Faculty of Mechanical Engineering Czech Technical University in Prague Karlovo nám. 13 121 32 Prague 2 Czech Republic Institute of Metallurgy Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia

Spherical Ag nanoparticles(AgNPs) with a diameter of 20 nm or smaller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term stability of AgNPs was investigated. UV/Vis spectrophotometry, transmission electron microscopy, and dynamic light scattering measurements revealed that the long-term stability of AgNPs was influenced by light and temperature conditions. The most significant loss of stability was observed for the AgNPs stored in daylight at room temperature. The AgNPs stored under these conditions began to lose their stability after approximately 30 d; after 100 d, a substantial amount of agglomerated particles settled to the bottom of the Erlenmeyer flask. The AgNPs stored in the dark at room temperature exhibited better long-term stability. Weak particle agglomeration began at approximately the 100 th day. The AgNPs stored in the dark at about 5℃ exhibited the best long-term stability; the AgNPs stored under such conditions remained spherical, with a narrow size distribution, and stable(no agglomeration) even after 6 months. Zeta-potential measurements confirmed better dispersity and stability of AgNPs stored under these conditions.

关键词： silver nanoparticles stability storage conditions green synthesis Parachlorella kessleri

The drivers of Child Mortality during the 2012–2016 drought in La Guajira, Colombia

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International Journal of disaster Risk Science 2020年第1期11卷 87-104页

作者： diana Contreras Alex Voets jana Junghardt Srirama Bhamidipati Sandra Contreras Research Center for Integrated disaster Risk Management(CIGIdEN) Pontifical Catholic University of Chile7820436 MaculSantiagoChile School of Engineering Newcastle UniversityNewcastle upon TyneNorthumbria NE17RUUK Caritas Switzerland BogotaD.C.110231Colombia Caritas Switzerland 6002 Luzern LucernaSwitzerland Faculty of Technology Policy and ManagementDelft University of Technology2628 BX DelftThe Netherlands Communication and Language Pontifical Xavierian UniversityBogotaD.C.110231Colombia

during the 2012–2016 drought in La Guajira,Colombia, child mortality rates rose to 23.4 out of *** of these children belonged to the Wayuu indigenous community, the largest and one of the most vulnerable in Colombia. At the municipal level, this study found a significant positive correlation between the average child mortality rate and households with a monthly income of less than USd 100, the number of people without access to health insurance, being part of the indigenous population,being illiterate, lacking sewage systems, living in rural areas, and large households with members younger than5 years old and older than 65 years old. No correlation was found with households without access to a water *** stepwise regression analysis showed that households with a monthly income of less than USd 100, no members older than 65 years old, but several children younger than5 years old, account for 90.4% of the child mortality *** study concludes that, if inhabitants had had better incomes or assets, as well as an adequate infrastructure,they could have faced the drought without the observed increase in child mortality.

关键词： Child mortality Climate change drought Socioeconomic vulnerability Water management Wayuu indigenous community

Interaction of a root-knot nematode (Meloidogyne hapla) and plant intraspecific diversity in clover-grass communities

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Journal of Plant Ecology 2019年第1期12卷 1-9页

作者： Xiaohui Guo jana S.Petermann Susanne Wurst dahlem Centre of Plant Sciences Institute of BiologyFreie Universität BerlinKönigin-Luise-Str.1-3Berlin D-14195Germany Key Laboratory of Biological and Ecological Engineering Ministry of EducationInstitute of Biodiversity ScienceFudan UniversitySonghu Road 2005Shanghai 200438China Berlin-Brandenburg Institute of Advanced Biodiversity Research Altensteinstr.34Berlin D-14195Germany department of Ecology and Evolution University of SalzburgHellbrunnerstr.34Salzburg 5020Austria

Aims Soil organisms can influence the plant diversity-productivity rela-tionship at species level;however,little is known about their role in the relationship at an intraspecific *** study aimed to investigate the interaction between the effects of plant intraspe-cific diversity and a root-knot nematode on primary production and community *** A greenhouse experiment was conducted by using intraspecific diversity of a clover-grass community through sowing 2-,4-,8-and 16-cultivar mixtures of Trifolium pratense *** Lolium perenne *** by adding the nematode Meloidogyne *** investigated the effects of plant intraspecific diversity and *** on biomass of plant community,biomass of cultivar individuals and community *** Findings We found that *** dominated the communities,yet its bio-mass was not affected by the *** hapla influ-enced the effect of plant intraspecific diversity on aboveground biomass of *** at the four-cultivar mixture level of plant intraspecific *** evenness increased linearly with increasing plant intraspecific diversity,and *** affected community evenness at the four-cultivar mixture *** ***-ense and *** cultivars differed in aboveground *** on plant intraspecific diversity and cultivar identity,nematode addition positively affected the aboveground biomass of *** *** response of *** cultivars to *** and to various plant intraspecific diversity levels influenced the intraspecific diversity-productivity *** study high-lights the influence of *** on the effect of plant intraspecific diversity on aboveground biomass of ***,suggesting that future research on the impact of intraspecific plant diversity on eco-system functions should consider the effects of soil organisms.

关键词： nematode diversity-productivity relationship biomass legume-grass community

Accretion flow properties of XTE J1118+480 during its 2005 outburst

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Research in Astronomy and Astrophysics 2020年第11期20卷 222-230页

作者： dipak debnath debjit Chatterjee Arghajit jana Sandip K.Chakrabarti Kaushik Chatterjee Indian Centre for Space Physics 43 ChalantikaGaria St.Rd.Kolkata700084India Physical Research Laboratory NavrangpuraAhmedabad 380009India

We study spectral and temporal properties of Galactic short orbital period transient black hole XTE J1118+480 during its 2005 outburst using archival data of RXTE PCA and HEXTE instruments in the combined energy range of 3−100 *** analysis with the physical two component advective flow(TCAF)model allows us to understand the accretion flow properties of the *** found that this outburst of XTE J1118+480 is an unconventional outburst as the source was only in the hard state(HS).Our spectral analysis suggests that during the entire outburst,the source was highly dominated by the low angular momentum sub-Keplerian halo *** the source was active in radio throughout the outburst,we make an effort to estimate X-ray contribution of jets to total observed X-ray emissions from the spectral analysis with the TCAF *** total X-ray intensity shows a similar nature of evolution as that of radio and jet X-ray *** allowed us to define this‘outburst’also as a jet dominated‘outburst’.Total X-ray flux is also found to subside when jet activity *** detailed spectral analysis also indicated that although the source was only in the HS during the outburst,in the late declining phase the spectrum became slightly softer due to the slow rise in the Keplerian disk rate.

关键词： X-Rays binaries-stars black holes-stars individual (XTE J1118+480)-accretion,accretion disks-ISM jets and outflows-radiation dynamics

Rilmenidine prevents blood pressure increase in rats with compromised nitric oxide production

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Acta Pharmacologica Sinica 2004年第12期25卷 74-80页

作者： Mria GEROV,Jozef TRK,Ol’ga PECHV,jana MATUKOV Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute of Pathophysiology Medical School Comenius University Bratislava Slovak Republic Now in Center for Blood Research and department of Pathology Harvard MedicalSchool Boston USA.

AIM: To search tools of high blood pressure in the model of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilmenidine, agonist of imidazoline receptors, which was suggested to modulate central sympathetic outflow. METHOdS: Three experimental groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine methyl ester (L-NAME) 40 mg·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of imidazoline receptors rilmenidine 3 mg·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasmeasured weekly noninvasively. At the end of experiment aortic ring isometric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determined. RESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. Rilmenidine administered simultaneously with L-NAME (group II) prevented the increase of blood pressure which did not differ significantly from control values; aortic ring relaxation to acetylcholine did not differ from control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: Rilmenidinehas aremarkable role inNO-defective hypertension, possibly by inhibiting central sympathetic outflow and by affecting receptors in vascular smooth muscle also. The prime cause of hypertension in this experimental model - the compromised production of NO due to inhibition of NOS - was not affected by rilmenidine.

关键词： NO deficiency hypertension imidazoline receptor nitric-oxide synthase sympathetic activity

Effects of Organic Matter-Rich Amendments on Selenium Mobility in Soils

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Pedosphere 2019年第6期29卷 740-751页

作者： Petra SMAZíKOVá Luká? PRAUS Jirina SZáKOVá jana TREMLOVá Ale? HANC Pavel TLUSTOS department of Agro-Environmental Chemistry and Plant Nutrition Faculty of Agrobiology Food and Natural Resources Czech University of Life Sciences Prague

Soil organic matter (SOM) plays an important role in the Se dynamics in soil. The potential effects of vermicompost and digestate as important sources of SOM on selenium (Se) mobility were assessed in this study. Three soils differing in their physicochemical parameters, fluvisol, chernozem, and luvisol, were chosen, and three types of vermicomposts based on various bio-waste materials as digestate (vermicompost 1), kitchen waste with woodchips (vermicompost 2), and garden bio-waste (vermicompost 3) were used due to their high organic matter content. Additionally, digestate samples alone were applied. To evaluate the potential effect of vermicompost application on sorption characteristics of soils, batch sorption experiments were performed. The results showed a predominant effect on Se species in the soils, where selenite sorbed more intensively compared to selenate, regardless of the soil and ameliorative material applied. In the control, the soil sorption ability of selenite tended to decrease in the order: fluvisol > luvisol > chernozem. However, these differences were not significant. Moreover, the effects of the ameliorative materials depended on both soil and amendment used. In fluvisol, all the amendment applications resulted in a decrease in distribution coefficient ( K d values) of Se, whereas in chernozem, this effect was observed only for the digestate-based vermicompost 1. Increasing K d levels were reported in luvisol treated with digestate;the application of garden bio-waste-based vermicompost 3 tended to decrease the K d values. Further studies are required on long-term effects of these amendments on Se mobility in soils and the role of individual organic matter fractions in this context.

关键词： Batch sorption experiments Bio-waste material Selenite Selenate Sorption isotherms Vermicompost