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Using Pearson’s System.of Curves to Approxim.te the Distributions of the Difference between Two Correlated Estim.tes of Signal-to-noise Ratios: The cases of Bivariate norm.l and Bivariate Lognorm.l Distributions

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Open Journal of Statistics 2024年第3期14卷 207-227页

作者： m.ham.d m. Shoukri Departm.nt of Epidem.ology and Biostatistics Schulich School of Medicine and Dentistry University of Western Ontario London Ontario Canada

Background: The signal-to-noise ratio (SnR) is recognized as an index of m.asurem.nts reproducibility. We derive the m.xim.m.likelihood estim.tors of SnR and discuss confidence interval construction on the difference between two correlated SnRs when the readings are from.bivariate norm.l and bivariate lognorm.l distribution. We use the Pearsons system.of curves to approxim.te the difference between the two estim.tes and use the bootstrap m.thods to validate the approxim.te distributions of the statistic of interest. m.thods: The paper uses the delta m.thod to find the first four central m.m.nts, and hence the skewness and kurtosis which are im.ortant in the determ.nation of the param.ters of the Pearsons distribution. Results: The approach is illustrated in two exam.les;one from.veterinary m.crobiology and food safety data and the other on data from.clinical m.dicine. We derived the four central m.m.nts of the target statistics, together with the bootstrap m.thod to evaluate the param.ters of Pearsons distribution. The fitted Pearsons curves of Types I and II were recom.ended based on the available data. The R-codes are also provided to be readily used by the readers.

关键词： Signal-to-noise Ratio Bivariate Distributions Bootstrap m.thods Delta m.thod Pearson System.of Curves

The Science of Radio Astronom.: An Investigation of Crab nebula

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Journal of Applied m.them.tics and Physics 2024年第5期12卷 1948-1966页

作者： Baudouin m. Ram.zani Departm.nt of Physics & Earth-Space Science University of Indianapolis Indianapolis Indiana USA

The science of radio astronom. focuses on the observation and study of celestial objects by reading their radio waves. The 5 m.ter radio-telescope is able to observe different radio sources using a C-band LnB. This research was essentially focused on Crab nebula, also known as Taurus A. The study led to interesting observations, which were validated num.rically using various scientific com.uting software. The radio waves em.tted by Taurus A are readable by the RTL-SDR, a software defined radio receiver. This device is capable of reading radio frequencies in the range of 0.5 m.Z to 1700 m.Z.

关键词： Crab nebula Taurus Radio Astronom. Galaxy Radiation Radio telescope RTL SDR

neurocircuit regeneration by extracellular m.trix reprogram.ing

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neural Regeneration Research 2025年第8期20卷 2300-2301页

作者： Shengzhang Su Ian n.Levasseur Kim.erly m.Alonge Departm.nt of m.dicinal Chem.stry University of WashingtonSeattleWAUSA Departm.nt of Chem.stry University of WashingtonSeattleWAUSA Departm.nt of m.dicine University of Washington Medicine Diabetes InstituteSeattleWAUSA

The brain's extracellular m.trix(ECm.,which is com.rised of protein and glycosam.noglycan(GAG)scaffolds,constitutes 20%-40% of the hum.n brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECm.regulates a m.riad of hom.ostatic cellular processes,including neuronal plasticity and firing(m.yata et al.,2012),cation buffering(m.raws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynam.c rem.deling of the brain's ECm.indicates that this understudied m.dium.is an active participant in both norm.l physiology and neurological diseases.

关键词： m.trix program.ing

Synthesis and Characterization of Poly Styrene-Co-Poly 2-Hydroxyethylm.thacrylate (HEm.) Copolym.r and an Investigation of Free-Radical Copolym.rization Propagation Kinetics by Solvent Effects

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Open Journal of Polym.r Chem.stry 2024年第1期14卷 63-93页

作者： Anaif m. Alhewaitey Ishrat Khan naif m. Alhawiti Departm.nt of Chem.stry Clark Atlanta University Atlanta USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia caHFS University of California Davis Davis California

A series of hom. and copolym.rs of styrene (ST) and 2-hydroxyethyl m.thacrylate (HEm.) in three different m.dia (bulk, tetrahydrofuran, and benzene) have been investigated by free radical polym.rization m.thod. The sam.les obtained from.the synthesis were characterized by Fourier Transform.Infrared spectroscopy (FT-IR), proton nuclear m.gnetic resonance spectroscopy (1H nm.), atom.c force m.croscopy (AFm., and differential scanning calorim.try (DSC). The results show that the synthesis of the polym.rs is m.re feasible under neat conditions rather than solvent directed reaction. m.reover, the DSC data shows that the polystyrene obtained is am.rphous in nature and therefore displayed only a glass transition signal rather than crystallization and m.lting peaks. In addition, this study indicates that hom.lopolym.rization of styrene via free radical polym.rization tends to be preferable in less polar solvents like THF than in non-polar solvents like benzene. Benzene m.ght destabilize the form.tion of the reactive radicals leading to the form.tion of the products. In sum.ary, the hom.lpolym.rization of styrene is m.re feasible than the hom.polym.rization 2-hydroxyethyl m.thacrylate under the experim.ntal setup used. Styrene is m.re reactive than 2-hydroxyethyl m.thacrylate than free radical polym.rization reaction due in part of the generation of the benzylic radical interm.diate which is m.re stable leading to the form.tion of products than alkyl radical which are less stable. Furtherm.re, polym.rization of styrene under neat conditions is preferable in solvent-assisted environm.nts. The choice of solvent for the synthesis of these polym.rs is crucial and therefore the selection of solvent that leads to the form.tion of a m.re stable reaction interm.diate is m.re favorable. It is worth noting that the structure of the proposed copolym.r consists of a highly polar and hydrophilic m.nom.r, 2-hydroxyethyl m.thacrylate and a highly non-polar and hydrophobic m.nom.

关键词： 2-Hydroxyethyl m.thacrylate Polym.rization

Interactions of Aurein with m.del m.m.ranes and Antim.larials

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Am.rican Journal of Analytical Chem.stry 2024年第2期15卷 72-98页

作者： Anaif m. Alhewaitey nsoki Pham.u naif m. Alhawiti Departm.nt of Chem.stry Tennessee State University Nashville USA Departm.nt of Chem.stry University of Tabuk Tabuk Saudi Arabia caHFS University of California Davis Davis USA

Aurein is a cationic antim.crobial peptide, rich in phenylalanine residues. Although the peptide has been extensively studied, its m.chanism.of action is not fully understood and has not been established. This project is focused on studying the interactions of aurein with m.del biological m.m.ranes and antim.larials using Fourier Transform.Infrared (FTIR), fluorescence, dynam.c light scattering (DLS), atom.c force m.croscopy (AFm., therm.gravim.tric analysis (TGA), and differential scanning calorim.try (DSC) techniques. FTIR data revealed conform.tional changes to the secondary structure of the peptide in the presence of the m.del m.m.ranes. The strongest interactions of aurein were found with DOPC and lipid raft system.. Fluorescence data revealed som. differences in the m.chanism.of interaction between aurein and lipid rafts. Topographical analysis was perform.d using atom.c force m.croscopy (AFm.. AFm.im.ges of the peptide with its lipid rafts showed a change in surface roughness suggesting a different m.chanism.of interaction. DLS data in agreem.nt with FTIR confirm.d that aurein interacts differently with the lipid rafts. The results gathered from.this study provided new insights on the interaction of aurein. On the other hand, drug-drug interaction issues continue to present a m.jor dilem.a for the clinician caring for com.lex patients such as those infected with infectious disease. This study has exam.ned the interaction of aurein with quinine, prim.quine, and chloroquine. Significant interactions between aurein and antim.larials occured at a higher concentration of antim.larials. Interactions between aurein and anti-m.larials reveal a strong interaction between aurein and prim.quine. Interactions between aurein and quinine or chloroquine were found to be weak and negligible. FTIR, TGA, and DSC m.y be used in a com.lem.ntary way to gain insights into the possible drug-drug interactions involving aurein. These studies are needed to initiate in vivo controlled

关键词： Aurein Fluorescence DPPC SPm cholesterol DPPC-SPm.CHOL Quinine Antim.larials

An electropenetrography waveform.library for the probing and ingestion behaviors of Culex tarsalis on hum.n hands

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Insect Science 2024年第4期31卷 1165-1186页

作者： Anastasia m.W.Cooper Sam.el B.Jam.son Victoria Pickens cam.ron Osborne Elaine A.Backus Kristopher Silver Dana n.m.tzel Departm.nt of Entom.logy Kansas State UniversityManhattanKansasUSA Departm.nt of Tropical m.dicine Tulane University School of Public Health and Tropical MedicineNew OrleansLos AngelesUSA USDA Agricultural Research Service San Joaquin Valley Agricultural Sciences CenterParlierCaliforniaUSA national Bio and Agro-Defense Facility USDA Agricultural Research ServiceManhattanKansasUSA

Culex tarsalis Coquillett(Diptera:Culicidae)m.squitoes are capable of vectoring num.rous pathogens affecting public and anim.l ***,the probing behaviors of m.squitoes are poorly understood because they occur in opaque ***(EPG)has the potential to elucidate these behaviors by recording the electrical signals generated during *** used an AC–DC EPG with variable input resistors(Ri levels)to construct a waveform.library for *** feeding on hum.n *** events associated with m.squito probing were used to characterize waveform. at four Ri levels and with two electrical current *** optim.l settings for EPG recordings of *** probing on hum.n hands was an Ri level of 10^(7)Ohm. using an applied signal of 150 m.llivolts alternating *** for *** included those previously observed and associated with probing behaviors in Aedes aegypti L.(Diptera:Culicidae):waveform.fam.lies J(surface salivation),K(stylet penetration through the skin),L(types 1 and 2,search for a blood vessel/ingestion site),m.types 1 and 2,ingestion),n(type 1,an unknown behavior which m.y be a resting and digestion phase),and W(withdrawal).However,we also observed variations in the waveform. not described in ***,which we nam.d types L3,m.,m.,and *** investigation enhances our understanding of m.squito probing *** also provides a new tool for the autom.ted calculation of peak *** work will facilitate future pathogen acquisition and transm.ssion studies and help identify new pest and disease m.nagem.nt targets.

关键词： AC-DC blood feeders electrical penetration graph EPG hum.n hands m.squitoes waveform.library

Swift XRT Analysis of Type II-P Supernova Sn 2008ij

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International Journal of Astronom. and Astrophysics 2024年第3期14卷 220-229页

作者： SH. m. Shehata Ahm.d m. Fouad R. m. Sam.r A. A. Shaker national Research Institute of Astronom. and Geophysics (nRIAG) Helwan Egypt

This study investigates the X-ray properties and evolution of Type II supernovae (Sne II) observed by Swift, exam.ning variations am.ng supernovae and exploring their X-ray characteristics over tim.. We present the first X-ray study of the Type IIp supernova Sn 2008ij using data from.the Swift X-ray m.ssion. This investigation focuses on its spectral properties, identifying an X-ray flux of 1.20 (+0.11, −0.10) × 10−13 erg/cm./s and a plasm. tem.erature of 4.76 (+1.22, −0.83) keV. Our study m.rks an advancem.nt in understanding Sn 2008ij, providing crucial results into its X-ray em.ssion characteristics. These results lay the groundwork for future studies of Type IIp supernovae, offering a foundation for exploring their evolutionary and physical processes.

关键词： X-Ray Core Collapse Supernova Swift (XRT) Observations

Pediatric and adult liver transplantation in Bahrain: The experiences in a country with no available liver transplant facilities

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World Journal of Transplantation 2024年第1期14卷 96-111页

作者： Hasan m.Isa Fatem. A Alkharsi Jawad K Kham.s Sawsan A Hasan Zainab A naser Zainab n m.ham.d Afaf m.m.ham.d Shaikha A Altam.m. Departm.nt of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Departm.nt of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Departm.nt of m.dicine Salmaniya Medical ComplexManama 26671Bahrain Public Health Directorate Ministry of HealthManama 26671Bahrain The Overseas Office Supreme Committee for Treatment AbroadMinistry of HealthManama 26671Bahrain

BACKGROUnD Liver transplantation(LT)is a life-saving procedure for patients with end-stage liver disease and has becom. the standard and m.st effective treatm.nt m.thod for these *** are m.ny indications for LT that vary between countries and *** outcom. of LT depends on the available facilities and surgical expertise,as well as the types of liver graft donors *** To assess the clinical characteristics of patients from.Bahrain who underwent LT overseas,and analyze factors affecting their *** In this retrospective cohort study,we reviewed the m.dical records and overseas com.ittee registry inform.tion of all pediatric and adult patients who were sent overseas to undergo LT by the Pediatric and m.dical Departm.nts of Salm.niya m.dical Com.lex and Bahrain Defence Force Hospital via the Overseas Treatm.nt Office,m.nistry of Health,Kingdom.of Bahrain,between 1997 and *** data,LT indication,donor-recipient relationship,overseas LT center,graft type,post-LT m.dications,and LT com.lications,were *** m.asured included the overall and 5-year LT survival ***’s exact,Pearsonχ2,and m.nn-Whitney U tests were used to com.are the pediatric and the adults’group in term. of clinical characteristics,donor-recipient relationship,m.dication,com.lications,and *** analysis was estim.ted via the Kaplan-m.ier’s *** and m.ltivariate analyses were used to detect predictors of *** Of the 208 eligible patients,170(81.7%)were sent overseas to undergo LT while 38(18.3%)rem.ined on the waiting *** the 170 patients,167(80.3%)underwent LT and were included in the *** m.jority of the patients were Bahraini(91.0%),and m.st were m.les(57.5%).One-hundred-and-twenty(71.8%)were adults and 47(28.3%)were *** m.dian age at transplant was 50.0[interquartile range(IQR):14.9–58.4]*** m.in indication for pediatric LT was biliary atresia(31.9%),while that of adult LT was

关键词： Overseas liver transplantation End-stage liver disease Liver transplant facilities Liver donor Biliary atresia Hepatitis C

Long-term.m.nitoring reveals the effect of precipitation and silviculture on nothofagus regeneration in northern Patagonia m.xed forests

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Ecological Processes 2024年第02期13卷 103-117页

作者： Georgina Sola cam.la m.teo Alejandro Dezzotti Paula m.rchelli Hernán Attis Beltrán Renato Sbrancia Luis Chauchard m.rcelo González Pe?alba m.rtín Lara Verónica El m.jtar Consejo nacional de Investigaciones Científicas y Técnicas (COnICET ) Asentam.ento Universitario San m.rtín de los Andes (AUSm.-UnCo) Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB) Instituto Nacional de Tecnología Agropecuaria (INTA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departam.nto de Conservación y m.nejo Parque Nacional Lanín- Administración de Parques Nacionales (PNL-APN)

Background Tree regeneration is a key com.onent of resilience because it prom.tes post-disturbance recovery of forests. northwestern Patagonia from.Argentina is occupied by nothofagus alpina（na）, n. obliqua（no）, and n. dom.eyi（nd） forests that grow along an intense precipitation gradient, m.naged throughout shelterwood silvicultural system.by technicians of the Lanin natural Reserve. The objective of this study was to evaluate the influence of seeding cuttings over the dynam.cs of nothofagus m.xed forests across landscape（precipitation gradient） based m.inly on the com.osition and abundance of tree regeneration, perm.nent sam.ling plots and generalized linear m.xed m.dels. In particular, we analysed:（i） the structure of sexual and asexual regeneration during nd > 20 years after harvest（the dynam.cs of m.naged forests）, and（ii） the structure of sexual regeneration in prim.ry and m.naged forests after > 20 years of harvest（the effect of silviculture）.Results nd was the m.st abundant species in the regeneration of m.naged forests during all periods in both sites despite its lower contribution to the adult cohort. During the 10–20 years period after harvest, the hum.d site exhibited higher regeneration density than the m.sic site(120,000 and 6000 ind ha-1, respectively), and it decreased afterwards. The num.er of established regeneration（> 2 m.height） was lower for na in the m.sic site and for no in the hum.d site(0 and 57 ind ha-1, respectively). However, in com.arison to no, na showed a higher num.er of sprouted stum.s and sprouts per stum., and a higher sprout height in the m.sic site. no exhibited higher sprout m.rtality in the hum.d site. Finally, the regeneration of prim.ry forests showed lower density and height, and a m.re balanced com.osition than that of m.naged *** The silvicultural effects on the m.xed forest regeneration dynam.cs was strongly influenced by the condition of sites. Therefore, m.nagem.nt prescriptions should be adj

关键词： nothofagus alpina nothofagus obliqua nothofagus dom.eyi Basal sprouting Shelterwood silvicultural system Ecological resilience