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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

Im.act on Soil Organic C and Total Soil N from.Cool- and Warm.Season Legum.s Used in a Green m.nure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark b. Neely Francis m. Rouquette Jr. Cristine L.S. m.rgan Frank m. Hons William.L. Rooney Gerald R. Sm.th Departm.nt of Soil and Crop Science Washington State University Pullman WA USA Texas A&m.AgriLife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Departm.nt of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legum.s are im.ortant com.onents of livestock production system. in East Texas and the southeastern US. Forage legum.s contribute nitrogen (N) to cropping system. through biological N fixation, and their seasonal biom.ss production can be m.naged to com.lem.nt forage grasses. Our research objectives were to evaluate both warm. and cool-season annual forage legum.s as green m.nure for biom.ss, N content, ability to enhance soil organic carbon (SOC) and soil N, and im.act on post season forage grass crops. Nine warm.season forage legum.s (WSL) were spring planted and incorporated as green m.nure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatm.nts. Eight cool-season forage legum.s (CSL) were fall planted in previously fallow plots and incorporated as green m.nure in late spring. Sorghum.sudangrass (Sorghum.bicolor x Sorghum.bicolor var. sudanense) was planted over all treatm.nts in early sum.er after forage rye harvest and incorporation of CSL treatm.nts. Sorghum.sudangrass was harvested in June, August and Septem.er, and treatm.nts were evaluated for dry m.tter and N concentration. Soil cores were taken from.each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm. and soil C and N were m.asured using com.ustion analysis. Nylon m.sh bags containing plant sam.les were buried at 15 cm.and used to evaluate decom.osition rate of above ground legum. biom.ss, including change in C and N concentrations. m.ngbean (Vigna radiata L. [Wilczek]) had the highest shoot biom.ss yield (6.24 t Dm.ha-1) and contributed the m.st total N (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the WSL tested. Decom.osition rate of WSL biom.ss was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum.sativum.L. spp. sativum., arrow leaf clover (Trifolium.vesiculosum.Savi.), and crim.on clover (Trifolium.incarnatum.L.) were the m.st productive CSL in this trial. Austrian winter pea

关键词： Annual Legum.s Soil N Soil Organic C Green m.nure Deer browse Forage Cropping System.

Liquid crystal im.unosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： SANDRO C.OLIVEIRA m.RIA S.SOARES bÁRbARA V.GONÇALVES ANDREIA C.m.RODRIGUES Am.DEU m.V.m.SOARES RITA G.SObRAL NUNO F.SANTOS JAN NEDOm. PEDRO L.ALm.IDA CARLOS m.RQUES CICECO-Aveiro Institute of m.terials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3N Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4Hb-Institute for Health and bioeconom. School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CESAm.Centre for Environm.ntal and m.rine Studies and Departm.nt of biology University of Aveiro3810-193 AveiroPortugal Departm.nt of Telecom.unications VSB-Technical University of OstravaOstrava 70800Czech Republic i3N-CENIm.T School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Departm.nt of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consum.tion of contam.nated food m.y cause serious illnesses,and traditional m.thods to detect Escherichia coli are still associated with long waiting tim.s and high costs given the necessity to transport sam.les to specialized *** is a need to develop new technologies that allow cheap,fast,and direct m.nitoring at the site of ***,in this work,we developed optical im.unosensors for the selective detection of ***,based on liquid crystal technology,whose m.lecules can align in different m.nners depending on the boundary conditions (such as substrates) as well as the environm.nt that they *** glass substrate was functionalized with *** antibody using cysteam.ne as an interm.diate,and a vertical alignm.nt was im.osed on the liquid crystal m.lecules by using Dm.AP during *** presence of bacteria disrupts the alignm.nt of the liquid crystal m.lecules,changing the intensity of light em.rging between cross polarizers,m.asured using a polarized optical m.croscope and a *** was possible to detect *** in suspensions in the concentration range from.2.8 cells/m. to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contam.nated water sam.les.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instrum.nts.

关键词： crystal alignm.nt analysis

Tilted global solar irradiance in bahrain: an experim.ntal study

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CLEAN ENERGY 2024年第2期8卷 27-34页

作者： Vasilikos, N. Georgantopoulou, C. Alajaim., H. Alm.jed, S. H. Ahm.d, m. m.thioulakis, D. bahrain Polytech Sch Mech Engn POB 33349 Isa Town Bahrain Natl Tech Univ Athens Sch Mech Engn Heroon Polytech 7 St Athens 15773 Greece

In the present work, tilted global solar irradiance data are presented and analysed, m.asured for a period of 1 year on the cam.us of bahrain Polytechnic, Kingdom.of bahrain, from.both a fixed photovoltaic panel and a m.ving one via a two-axis solar tracker. The fixed panel faces south with an angle of 26 degrees with respect to the horizontal, coinciding with the local geographical latitude. The second panel is m.ved by two m.tors, controlled by a global positioning system.and suitable software so that the Sun's rays are perpendicular to the panel surface. A pyranom.ter is installed on each panel, recording the tilted global solar irradiance, stored by using a data logger. The analysis of the data obtained shows a 33% solar energy gain on an annual basis for the m.ving panel (2780 versus 2088 kWh/m. on the fixed panel). m.re im.ortantly, in June, when the energy dem.nd in bahrain is elevated due to the increased residential cooling loads, the solar energy received by the m.ving panel is 54.7% higher com.ared with that of the fixed panel. On a percentage basis, the increase in solar energy from.the m.ving panel is profound in the early m.rning and late evening hours. m.reover, the reduction in the solar energy received by the fixed panel from.m.y to June does not appear in the m.ving panel because of the adjustable orientation of the latter. Throughout the year, the m.an daily solar power varies between 0.37 and 0.56 kW/m. for the fixed panel, and 0.45 and 0.70 kW/m. for the m.ving panel. In winter, solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28% of the corresponding m.an. The data presented are useful for potential solar investm.nts in Gulf countries. Tilted global solar irradiance data are m.asured and analysed for a period of 1 year on the cam.us of bahrain Polytechnic, Kingdom.of bahrain, from.both a fixed photovoltaic panel and a m.ving one via a two-axis solar tracker. Graphical Abstract

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf Cooperation Council Countries SUN TRACKING ENERGY SYSTEm. PANELS WORLD

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

There is m.re to the knee joint than just the quadriceps:A system.tic review with m.ta-analysis and evidence gap m.p of ham.tring strength,flexibility,and m.rphology in individuals with gradual-onset knee disorders

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Journal of Sport and Health Science 2024年第4期13卷 521-536页

作者： Helder S.Lopes m.rina C.Waitem.n Liliam.b.Priore Neal R.Glaviano David m.bazett-Jones Ronaldo V.briani Fabio m.Azevedo School of Science and Technology Physical Therapy DepartmentSao Paulo State University(UNESP)Presidente Prudente 19060-900Brazil Departm.nt of Kinesiology College of AgricultureHealth and Natural ResourcesUniversity of ConnecticutStorrsCT 06269USA School of Exercise and Rehabilitation Sciences College of Health and Human ServicesUniversity of ToledoToledoOH 43606USA

background:Im.airm.nts in ham.tring strength,flexibility,and m.rphology have been associated with altered knee biom.chanics,pain,and *** the presence of these im.airm.nts in individuals with gradual-onset knee disorders is im.ortant and m.y indicate targets for assessm.nt and *** system.tic review aim.d to synthesize the literature to determ.ne the presence of im.airm.nts in ham.tring strength,flexibility,and m.rphology in individuals with gradual-onset knee ***:Five databases(m.DLINE,Em.ase,CINAHL,SPORTDiscus,and Web of Science)were searched from.inception to Septem.er *** studies com.aring ham.tring outcom.s(e.g.,strength,flexibility,and/or m.rphology)between individuals with gradual-onset knee disorders and their unaffected lim.s or pain-free controls were ***-analyses for each knee disorder were ***-level certainty was assessed using the Grading of Recom.endations Assessm.nt,Developm.nt,and Evaluation,and evidence gap m.ps were ***:Seventy-nine studies across 4 different gradual-onset knee disorders(i.e.,knee osteoarthritis(OA),patellofem.ral pain(PFP),chondrom.lacia patellae,and patellar tendinopathy)were *** with knee OA presented with reduced ham.tring strength com.ared to pain-free controls during isom.tric(standard m.an difference(Sm.)=-0.76,95%confidence interval(95%CI):-1.32 to-0.21)and concentric contractions(Sm.=-0.97,95%CI:-1.49 to-0.45).Individuals with PFP presented with reduced ham.tring strength com.ared to painfree controls during isom.tric(Sm.=-0.48,95%CI:-0.82 to-0.14),concentric(Sm.=-1.07,95%CI:-2.08 to-0.06),and eccentric contractions(Sm.=-0.59,95%CI:-0.97 to-0.21).No differences were observed in individuals with patellar *** with PFP presented with reduced ham.tring flexibility when com.ared to pain-free controls(Sm.=-0.76,95%CI:-1.15 to-0.36).Evidence gap m.ps identified insufficient evidence for chondrom.lacia patel

关键词： Chondrom.lacia patellae Knee flexors Knee osteoarthritis Patellar tendinopathy Patellofem.ral pain

Relevance of plasm. lipoproteins and sm.ll m.tabolites in assessm.nt of nutritional status am.ng patients with severe injuries

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重症医学（英文） 2024年第4期04卷 496-507页

作者： Verheul Esm.e A.H. Dijkink Suzan Krijnen Pieta Verhoeven Aswin Giera m.rtin Tsonaka Roula Hoogendoorn Jochem.m. Arbous Sesm. m. Peters Ron Schipper Inger b. Departm.nt of Traum. Surgery Leiden University Medical Center Leiden The Netherlands Acute Care Network West Netherlands Leiden The Netherlands Center for Proteom.cs and m.tabolom.cs Leiden University Medical Center Leiden The Netherlands Departm.nt of biom.dical Data Sciences Leiden University Medical Center Leiden The Netherlands Departm.nt of General Surgery Haaglanden Medical Center The Hague The Netherlands Departm.nt of Intensive Care Leiden University Medical Center Leiden The Netherlands Departm.nt of Intensive Care Haaglanden Medical Center The Hague The Netherlands

background::This study aim.d to identify plasm. lipoproteins and sm.ll m.tabolites associated with high risk of m.lnutrition during intensive care unit (ICU) stay in patients with severe ***::This observational prospective exploratory study was conducted at two level-1 traum. centers in the Netherlands. Adult patients (aged ≥18 years) who were adm.tted to the ICU for m.re than 48 h between July 2018 and April 2022 owing to severe injuries (polytraum., as defined by Injury Severity Scores of ≥16) caused by blunt traum. were eligible for inclusion. Partial least squares discrim.nant analysis was used to analyze the relationship of 112 lipoprotein-related com.onents and 23 sm.ll m.tabolites with the risk of m.lnutrition (m.dified Nutrition Risk in Critically Ill score). m.lnutrition was diagnosed based on Subjective Global Assessm.nt scores. The relationship of lipoprotein properties and sm.ll m.tabolite concentrations with m.lnutrition (during ICU adm.ssion) was evaluated using m.xed effects logistic ***::Overall, 51 patients were included. Lower (very) low-density lipoprotein ([V]LDL) (free) cholesterol and phospholipid levels, low particle num.er, and higher levels of LDL triglycerides were associated with a higher risk of m.lnutrition (variable im.ortance in projection [VIP] value >1.5). Low levels of m.st (V)LDL and interm.diate-density lipoprotein subfractions and high levels of high-density lipoprotein Apo-A1 were associated with the diagnosis of m.lnutrition (VIP value >1.5). Increased levels of dim.thyl sulfone, trim.thylam.ne N-oxide, creatinine, N, N-dim.thylglycine, and pyruvic acid and decreased levels of creatine, m.thionine, and acetoacetic acid were also indicative of m.lnutrition (VIP value >1.5). Overall, 14 lipoproteins and 1 sm.ll m.tabolite were significantly associated with a high risk of m.lnutrition during ICU adm.ssion ( P <0.05);however, the association did not persist after correcting the false discovery rate

关键词： Traum. Severely injured m.tabolites Lipoproteins m.lnutrition Nutritional status

Legum. Green m.nure and Intercropping for High biom.ss Sorghum.Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark b. Neely Francis m. Rouquette Jr. Cristine L. S. m.rgan Frank m. Hons William.L. Rooney Gerald R. Sm.th Departm.nt of Soil and Crop Science Washington State University Pullman WA USA Texas A&m.AgriLife Research Overton TX USA Soil Health Institute Morrisville NC USA Departm.nt of Soil and Crop Science Texas A&M University College Station TX USA

before the advent of cheap, synthetic fertilizers, legum.s were com.only used as green m.nure crops for their ability to fix atm.spheric nitrogen (N). A three-year study at Overton, TX exam.ned legum. integration into high-biom.ss sorghum.(Sorghum.bicolor L.) production system. on a Lilbert loam. fine sand recently cultivated after a fertilized berm.dagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crim.on clover (Trifolium.incarnatum.L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biom.ss sorghum.production system.to evaluate im.acts on N concentration, C concentration, and yield of high-biom.ss sorghum.and their im.acts on soil total N and soil organic carbon (SOC). m.in plots were split into crim.on clover green m.nure (CLGm. and winter fallow (FALL) followed by three sub-plots split into warm.season crop rotations: cowpea green m.nure (CPGm., cowpea-sorghum.intercrop (CPSR), and sorghum.m.nocrop (SORG). Three N fertilizer treatm.nts (0, 45, 90 kg N∙ha−1) were random.zed and applied as sub-sub plots. The CLGm.increased (P sorghum.biom.ss yield (16.5 t Dm.ha−1) 28% in year three but had no effect in the first two years. The CPSR treatm.nt reduced sorghum.yield up to 62% com.ared to SORG;whereas CPGm.increased sorghum.yield 56% and 18% the two years following cowpea incorporation. Rate of N fertilizer had no effect on sorghum.biom.ss yield. Decrease in SOC and soil N over tim. indicated m.neralization of organic N and m.y explain why no N fertilizer response was observed in sorghum.biom.ss yield. Cowpea showed strong potential as a green m.nure crop but proved to be too com.etitive for successful intercropping in high-biom.ss sorghum.production system..

关键词： High-biom.ss Sorghum Legum.s Green m.nure Intercrop Cowpea Crim.on Clover Soil Organic Carbon Soil Nitrogen