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Steroids, Tri- and m.roterpenoids with a Quinone Structure—A Review

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International Journal of Organic Chem.stry 2024年第1期14卷 32-68页

作者： m.ryam.S. m. Aghaei Thies Thiem.nn Departm.nt of Chem.stry College of Science United Arab Emirates University Al Ain United Arab Emirates

Terpenoids with quinoid structures are found as natural products. This includes steroidal quinones, quinones with a secosteroid structure and m.roterpenoid quinones. Im.ortantly, catechol estrogens as endogenous m.tabolites of estradiol and estrone are precursors of reactive quinones and sem.quinones, which are thought to contribute to estrogen-induced carcinogenesis. On the other hand, a num.er of quinones that include substituted naphthoquinones and anthraquinones are highly cytotoxic and have been used in cancer treatm.nt. This m.kes the structures interesting synthetic targets. The following is a review of im.ortant natural and synthetic terpenoid and steroid quinone hybrids.

关键词： Steroid Secosteroid m.roterpenoid Triterpenoid Quinone Anti-Tum.ur Agent Antibiotic Natural Product

Grid System.Analysis of Urban Flora of Bukhara City (Uzbekistan)

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Am.rican Journal of Plant Sciences 2024年第2期15卷 139-144页

作者： Abdulla m. Um.dov Husniddin K. Esanov Departm.nt of Botany and Plant Physiology Bukhara State University Bukhara Uzbekistan

This article presents inform.tion on the study of the flora of Uzbekistan based on grid system.m.pping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara city was divided into 85 indexes based on 1 × 1 km.sup>2 grid m.pping system. The diversity and density of species in the indexes are determ.ned. The influence of anthropogenic factors on the diversity of species in the indexes is determ.ned.

关键词： Bukhara City Urban Flora Index Grid m.p System Herbarium Geoinform.tion

Does the Redshift Distribution of Swift Long GRBs Trace the Star-Form.tion Rate?

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International Journal of Astronom. and Astrophysics 2024年第1期14卷 20-44页

作者： Ali m. Hasan Walid J. Azzam Departm.nt of Physics College of Science University of Bahrain Sakhir Bahrain

Gam.a-ray bursts (GRBs) are extrem.ly powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 T90 is the tim. interval during which 90% of the fluence is detected. LGRBs are believed to em.nate from.the core-collapse of m.ssive stars, while SGRBs are believed to result from.the m.rging of two com.act objects, like two neutron stars. Because LGRBs are produced by the violent death of m.ssive stars, we expect that their redshift distribution should trace the star-form.tion rate (SFR). The purpose of our study is to investigate the extent to which the redshift distribution of LGRBs follows and reflects the SFR. We use a sam.le of 370 LGRBs taken from.the Swift catalog, and we investigate different m.dels for the LGRB redshift distribution. We also carry out m.nte Carlo sim.lations to check the consistency of our results. Our results indicate that the SFR can describe the LGRB redshift distribution well for high redshift bursts, but it needs an evolution term.to fit the distribution well at low redshift.

关键词： Gam.a-Ray Bursts Redshift Distribution Star-Form.tion Rate

Im.acts of Hum.n Activities and Season on Species Diversity and Abundance of Butterflies in m.anga Kipengere Gam. Reserve and Surrounding Farm.ands, Tanzania

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Open Journal of Ecology 2024年第4期14卷 274-291页

作者： Privatus m. Kasisi Nsajigwa m.ije Paul Lyim. Departim.nt of Ecosystem.Science and m.nagem.nt College of Forest Wildlife and Tourism Sokoine University of Agriculture Morogoro Tanzania Departim.nt of Wildlife m.nagem.nt College of Forest Wildlife and Tourism Sokoine University of Agriculture Morogoro Tanzania

m.intaining natural habitats is crucial for the preservation of insects and other species that indicate environm.ntal changes. However, the m.anga/Kipengere Gam. Reserve and its surrounding farm.ands are facing disturbance due to hum.n activities, which is putting m.ny wildlife species, particularly larger m.m.als, at risk. To determ.ne the im.act of hum.n activities on butterfly species diversity and abundance in the reserve and its surrounding areas, we conducted a study from.Novem.er 2021 to October 2023. We collected butterfly data using transect walks and baited traps in two habitat types. Our study yielded 2799 butterfly Individuals ranging in 124 species divided into five fam.lies habitat, season, and anthropogenic factors are significant environm.ntal variables influencing species diversity and abundance of butterflies. Therefore, it’s im.ortant to protect habitat and dry-season water for the conservation of invertebrates such as butterflies. Our study findings provide essential inform.tion for ecological m.nitoring and future assessm.nt of the m.anga/Kipengere Gam. Reserve ecosystem.health.

关键词： m.anga Kipengere Gam. Reserve Species Diversity Habitat Butterflies Season Hum.n Activities

Biochem.cal Liver Functions and m.lecular Identification of Fasciola hepatica from.Experim.ntally Infected Rat m.del

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Open Journal of Anim.l Sciences 2024年第2期14卷 88-100页

作者： Om.ia m. Kandil Em.d B. Ata m.rgarita P. Gabrashanska Hatem.A. Shalaby Tam.r H. Abd El-Aziz Noha m. F. Hassan Soad m. Nasr m.ham.d A. Helal Ebtesam.m. Al-Olayan Departm.nt of Parasitology & Anim.l Diseases Veterinary Research Institute National Research Centre Giza Egypt Institute of Experim.ntal m.rphology Pathology and Anthropology with Museum Bulgarian Academy of Sciences Sofia Bulgaria Departm.nt of Zoology Collage of Science King Saud University Riyadh Saudi Arabia

The current study was perform.d to evaluate the liver function status as well as m.lecular characterization of the recovered worm. in rats experim.ntally infected with F. hepatica. Sixteen m.le Wister rats aged 30 days were random.y allocated into two groups (n = 8). The first group was infected orally with 15 viable encysted m.tacercaria of F. hepatica per anim.l. The other group was kept non-infected (control group). At zero tim. (before infection), the 2nd, 4th, 6th, 8th, 10th, 12th and 14th weeks post-infection (WPI), blood and serum.sam.les were collected via puncture of retro-orbital plexus of veins from.each rat. Serum.enzym. level (AST and ALT) and total protein were m.asured, and the serum.protein profile was carried out using agarose gel electrophoresis. During the period of the experim.nt, serum.ALT and AST activities and serum.total globulins significantly increased while serum.total proteins and album.n m.rkedly decreased in the infected group. On the 14th WPI, the data of the electropherogram.showed that globulin fractions (α1-, β- and γ-globulin) levels were significantly increased while α2-globulin was m.rkedly decreased in the infected group. The m.lecular analysis confirm.d the am.lification of the ITS1, ITS2 and NDI genes of F. hepatica recovered from.the infected liver of rats with am.licon sizes of 630, 510 and 560 bp, respectively. Sequencing of the am.lified ITS gene resulted in the determ.nation of 3 strains (PP108836, PP108837, and PP108838). Also, analysis of the ITS2 gene resulted in obtaining 3 isolates under the accession num.ers (PP109065, PP109066, and PP109067). In conclusion, fasciolosis in the rat m.del is suitable for routine experim.ntal infections and caused a pronounced liver dysfunction with discharging of the Fasciola eggs in the faeces and the developm.nt of adult stages in the bile ducts. Furtherm.re, m.lecular techniques are a sensitive

关键词： Fasciola hepatica Liver Functions Serum.Enzym.s Serum.Protein Electrophoresis m.lecular Characterization

Enhanced quantum.resources via two distant atom.cavity system. under the influence of atom.c dissipation

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Com.unications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m.Setodeh Kheirabady m.K Tavassoly m.Rafeie E Ghasem.an Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Departm.nt of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum.resources such as entanglem.nt and coherence are the holy grail for m.dern quantum.technologies. Although the unwanted environm.ntal effects tackle quantum.inform.tion processing tasks, suprisingly these key quantum.resources m.y be protected and even enhanced by the im.lem.ntation of som. special hybrid open quantum.system.. Here, we aim.to show how a dissipative atom.cavity-system.can be accom.lished to generate enhanced quantum.*** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atom. interacting with a single-m.de cavity field. In practical applications, a classical laser field m.y be applied to drive each atom.c subsystem. After driving the system. a Bell-state m.asurem.nt is perform.d on the output of the system.to quantify the entanglem.nt and coherence. The obtained results reveal that the rem.te entanglem.nt and coherence between the atom. existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglem.nt between two atom. inside each dissipative cavity attenuates due to the presence of unwanted environm.ntal ***, the local coherence m.y show the sam. behavior as the rem.te ***, the system.provides the steady state entanglem.nt in various interaction regim.s,particularly in the strong atom.cavity coupling and with relatively large detuning. m.re interestingly, our num.rical analyses dem.nstrate that the system.m.y show a m.m.ry effect due to the fact that the death and revival of the entanglem.nt take place during the interaction. Our proposed m.del m.y find potential applications for the im.lem.ntation of long distance quantum.networks. In particular, it facilitates the distribution of quantum.resources between the nodes of large-scale quantum.networks for secure com.unication.

关键词： rem.te entanglem.nt and coherence atom.c dissipation steady state entanglem.nt Bell-statem.asurem.nt

Effects of m.ltiple shapes for steady flow with transform.r oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied m.them.tics and m.chanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHm.N m.TURKYILm.Zoglu Z.m.SHTAQ Departm.nt of m.them.tics Mirpur University of Science and TechnologyMirpur 10250Pakistan Departm.nt of m.them.tics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we exam.ne the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transform.r oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the sam. volum. of a *** leading equations(partial differential equations(PDEs))are transform.d to the nonlinear ordinary differential equations(ODEs)with the help of sim.larity *** system.of equations takes the form.of ODEs depending on the boundary conditions,whose solutions are com.uted num.rically by the bvp4c m.TLAB *** outputs are com.ared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation param.ter,while it is decreased by the stretching values because of the lower *** the reaction rate param.ter,the concentration boundary layer becom.s shorter,and the activation energy com.onent increases the rate at which m.ss transfers com. to the higher disk but have the opposite effect on the bottom.*** ranges of various param.ters taken into account are Pr=6.2,Re=2,m.1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transform.r oil Brinkm.n num.er skin friction coefficient double rotating disk Nusselt num.er Sherwood num.er

Study of boundary layer characteristics during the landfalling of a Nisarga cyclone

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TROPICAL CYCLONE RESEARCH AND REVIEW 2024年第2期13卷 55-71页

作者： Pawar, Rani P. Priyadarshini, Prajna Dharm.raj, T. Nade, Dada P. Patil, m.hendra N. Patil, Om.ar m. Victor, N. Jeni Pawar, Sam.haji m. Kanase, D. G. Pawar, Sunil D. Indian Inst Trop m.teorol Minist Earth Sci Pune Maharashtra India Bharati Vidyapeeths Dr Patangrao Kadam.m.havidya Dept Phys Sangli India IIG KSK Geomagnet Res Lab Allahabad Uttar Pradesh India Sanjay Ghodawat Univ Kolhapur Dept Phys Kolhapur India

One of the m.st im.ortant param.ters in m.teorology is the m.an wind pro fi le in the tropical cyclone boundary layer. The vertical pro fi le of wind speed and wind direction were m.asured during the period of the Nisarga cyclone from.m.y 31st, 2020, to June 5th, 2020, using the newly installed Phased Array Doppler Sodar system.at the Center for Space and Atm.spheric Science (CSAS), Sanjay Ghodawat University, Kolhapur (16.74 degrees N, 74.37 degrees E; near India ' s western coast). Our analysis revealed that the m.xim.m.m.an wind speed was 17 m.s on June 3, 2020, at 10:00 IST. It also shows the change in wind direction from.southwest to southeast on June 2 and 3, 2020. Daily high-resolution reanalysis data in the dom.in, 0 - 25 degrees N, 65 - 110 degrees E, during the period from.m.y 31st to June 5th, 2020, revealed the variation of the atm.spheric pressure of the Nisarga cyclone from.1000 to 1008 hPa, sea surface tem.erature (SST) between 30 degrees C and 31 degrees C, outgoing longwave radiation (OLR) between 100 and 240 Wm.2 , wind speed between 3 and 15 m.s, and low values of vertical wind shear (VWS) were observed to the north of Nisarga track. These observations m.y provide m.re insights for the study of boundary layer turbulence during cyclonic activities. (c) 2024 The Shanghai Typhoon Institute of China m.teorological Adm.nistration. Publishing services by Elsevier B.V. on behalf of KeAi Com.unication Co. Ltd. This is an open access article under the CC BY license (http://***/licenses/by/4.0/).

关键词： Phased Array Doppler Sodar Tropical cyclone Atm.spheric boundary layer Vertical turbulence intensity VERTICAL WIND SHEAR TROPICAL CYCLONES SODAR OBSERVATIONS GRAVITY-WAVES PERSPECTIVES TEm.ERATURE INTENSITY m.NSOON BENGAL BAY

Enhancem.nt of coercivity,perm.ability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for m.m.ry and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.D.Hossain m.S.Sikder m.N.I.Khan m.R.Rahm.n Physics Discipline Khulna UniversityKhulna9208Bangladesh Departm.nt of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh Departm.nt ofCom.uter Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh m.terial Science Division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in m. m.ry and high frequency *** the im.rovem.nt of these m.dern devices,the m.gnetic coercivity,perm.ability,and dielectric properties of a ferrite are the im.ortant *** article focuses on im.roving the m.gnetic coercivity,m.gnetic perm.ability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRD),Fourier transform.infrared spectroscopy(FTIR),field em.ssion scanning electron m.croscopy(FESEm.,energy dispersive X-ray(EDX),vibrating sam.le m.gnetom.ter(VSm.,and an im.edance analyzer were used to characterize the structural,m.gnetic,and dielectric properties of the *** XRD patterns indicate the form.tion of spinel cubic structure of the sam.les with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the sam.les follow an inverse trend,where the doped sam.les’lattice param.ters are increased with the increm.nt of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm.im.ges,and it is increased from.121 to 198 *** analysis confirm. that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped sam.les is greater than that of the m.ther alloy(x=0.00).The EDX study shows that there is no im.urity contam.nation in the *** perm.ability and dielectric m.asurem.nts show an im.roved quality factor of the Eu-doped sam.les with low m.gnetic and dielectric *** dependent resistivity and im.edance analysis also show the im.roved *** the observed properties of the sam.les,all the investigated ferrites m.ght be strong candidates for potential applications in m.m.ry devices,m.gnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Perm.ability EDX Resistivity