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Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri F.l.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib m.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium lICPm ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR lyr of RR lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR lyr)

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Human biomonitoring of novel brominated flame retardants:A review on invasive and non-invasive biomarkers

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Emerging Contaminants 2024年第3期10卷 374-385页

作者： Oluwatoyin m.Olagoke Temilola O.Oluseyi Kelechi l.Njoku Stuart Harrad mohamed Abou-Elwafa Abdallah Department of Cell Biology and Genetics Faculty of ScienceUniversity of LagosAkokaLagos101017Nigeria Department of Chemistry Faculty of ScienceUniversity of LagosAkokaLagos101017Nigeria School of Geography Earth and Environmental SciencesUniversity of BirminghamBirminghamB152TTUnited Kingdom

Novel brominated flame retardants(NBFRs)are a group of chemicals applied mainly as alternatives to the phased-out polybrominated diphenyl ethers(PBDEs).However,toxicological studies show that NBFRs may pose health risks similar to *** present study reviews available information on the biomonitoring of NBFRs and their metabolites in humans through invasive and non-invasive biomarkers,as well as the toxicological effects of these chemicals both in vivo and in *** general,higher concentrations of NBFRs were reported in tissues of occupationally exposed adults from NBFR production facilities,e-waste recycling facilities and inhabitants living close to these areas,compared to the general *** is worth noting that NBFR human biomonitoring data are limited to few countries located in North America,Europe and Asia,while data from developing countries are *** from in vivo and in vitro toxicity studies show that several NBFRs can cause adverse health effects through various modes of action,mainly:hormone disruption,genotoxicity,endocrine disruption,and behavioural *** few studies have investigated the biotransformation of NBFRs in humans,evidence suggests that the toxicity of some NBFRs may be augmented through their metabolites,as in the case of 2,3,4,5-tetrabromobenzoic acid(TBBA),which may exhibit higher toxicity than its parent compound 2-ethylhexyl-2,3,4,5-tetrabromobenzoate(EH-TBB).more research is required to assess toxicity thresholds,toxic endpoints,and tolerable intakes for various NBFRs,and their metabolites in *** epidemiological studies are highly recommended to further understand the risk arising from human exposure to different NBFRs,particularly in occupational settings.

关键词： NBFRs Human biomonitoring Human exposure Biomarkers metabolites

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Enantioselective Synthesis,(Chir)optical Properties,and Postsynthetic Functionalization of Furan-Containing Oxa[5]-,Oxa[6]-,and Dioxa[6]helicenes

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CCS Chemistry 2024年第10期6卷 2439-2451页

作者： Wei Fu Valentina Pelliccioli Raquel Casares-lópez Juan m.Cuerva martin Simon Christopher Golz manuel Alcarazo Institut für Organische und Biomolekulare Chemie Georg-August-Universität Göttingen37077 Göttingen Departamento de Química Orgánica Universidad de GranadaUnidad de Excelencia Química Aplicada a Biomedicina y MedioambienteE-18071 Granada

An expedient synthesis of a series of configurationally stable oxa[5]helicenes,oxa[6]helicenes,and dioxa[6]helicenes has been developed using an intramolecular,highly enantioselective,Au-catalyzed,alkyne hydroarylation *** absolute configuration of the newly prepared structures has been established by crystallography,their inversion barriers have been determined theoretically and experimentally,and their chiroptical properties have been *** of these data with those reported for thia-or carbohelicenes sharing an otherwise identical helical framework enables the establishment of comprehensive correlations between the nature of the embedded(hetero)atom(s)and the magnitude of these *** studies on the postsynthetic functionalization of the oxahelicenes obtained are also ***,siteselective bromination at the 15-position in oxa[5]helicene 5d allows its subsequent manipulation into pyridine-containing aza-oxa[7]helicene 13d;while the two termini of oxa[6]helicene 7d have been intramolecularly cyclised into the pleiadeno[1,12,11-bcde]benzofuran derivative 15d by acidic *** transformations take place without erosion of the enantiopurity.

关键词： Au-catalysis enantioselective synthesis oxa[n]helicenes racemization dynamics postsynthetic functionalization

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Spatial analysis of Dengue through the reproduction numbers relating to socioeconomic features:Case studies on two Brazilian urban centers

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Infectious Disease modelling 2024年第1期9卷 142-157页

作者： Ana T.C.Silva Rejane C.Dorn lívia R.Tomás leonardo B.l.Santos lacita m.Skalinski Suani T.R.Pinho Departamento de Física Universidade Estadual de Feira de SantanaAv.Transnordestinas/n.Novo HorizonteFeira de Santana44036-900BABrazil Instituto de Física Universidade Federal da BahiaRua Barão de Jeremoabo s/nCampus Universitário de OndinaSalvador40170-115BABrazil Centro Nacional de monitoramento e Alertas de Desastres Naturais(CEmADEN) Estrada Dr.Altino Bondensan500São Josédos Campos12247-016SPBrazil Universidade Estadual de Santa Cruz Campus Soane Nazaréde AndradeRodovia Jorge AmadoKm 16SalobrinhoIlhéus45662-900BABrazil Instituto de Saúde Coletiva Universidade Federal da BahiaR.Basílio da Gamas/n-CanelaSalvador40110-140BABrazil Instituto Nacional de Ciência e Tecnologia-Sistemas Complexos Virtual InstitutionBrazil

The study of the propagation of infectious diseases in urban centers finds a close connection with their population's social characteristics and *** work performs a spatial analysis of dengue cases in urban centers based on the basic reproduction numbers,R0,and incidence by planning areas(PAs),as well as their correlations with the Human Development Index(HDI)and the number of *** analyzed dengue epidemics in 2002 at two Brazilian urban centers,Belo Horizonte(BH)and Rio de Janeiro(RJ),using PAs as spatial *** results reveal heterogeneous spatial scenarios for both cities,with very weak correlations between R0 and both the number of trips and the HDI;in BH,the values of R0 show a less spatial heterogeneous pattern than in *** BH,there are moderate correlations between incidence and both the number of trips and the HDI;meanwhile,they weakly correlate for ***,the absence of strong correlations between the considered measures indicates that the transmission process should be treated considering the city as a whole.

关键词： Dengue mathematical mode lBasic reproduction number Urban mobility Urban indices

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mid-term survival of the Optimys short stem: A prospective case series of 500 patients

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World Journal of Orthopedics 2024年第3期15卷 257-265页

作者： Bryan Hamans Sheryl de Waard Sjoerd Kaarsemaker Esther R C Janssen Inger N Sierevelt Gino m m J Kerkhoffs Daniël Haverkamp Department of Orthopaedic Surgery Xpert ClinicAmsterdam 1101EANetherlands Department of Orthopedic Surgery Amsterdam University Medical CenterAmsterdam 1105 AZNetherlands Esther R C Janssen Department of Orthopaedic SurgeryViecuri Medisch CentrumVenlo 5912 BLNetherlands Centre for Orthopaedic Research Spaarne ZiekenhuisHoofddorp 2134 TMNetherlands Department of Orthopaedic Surgery and Sports medicine Amsterdam UMC-Location AMCAmsterdam 1105 AZNetherlands Department of Orthopedic Surgery Xpert Orthopedic Surgery ClinicAmsterdam 1101 EANetherlands

BACKGROUND In recent years,there has been an increase in the number of total hip arthroplasty procedures in the younger patient *** active group has higher expectations of their prosthesis in comparison to the older population,and there is a greater physical demand for the *** femoral stems were in-troduced to retain proximal bone stock and joint biomechanics and became more common to implant in this specific ***,the long-term survival and functional outcomes of various short stems are still being investigated in different *** To determine the 5-year survival of the Optimys hip *** This was a prospective multicenter cohort study of 500 patients conducted in two hospitals in the *** patients received the Optimys short stem(mathys ltd,Bettlach,Switzerland).The prim.ry outcome measure was survival of the hip stem,with revision as the *** secondary outcome measurements included patient-reported outcome measures(PROms).Kaplan-meier analysis was used to calculate the 5-year survival ***-minus-log transformation was performed to calculate the 95%confidence interval(95%CI).mixed model analyses were performed to assess the course of the PROms during the 1st 2 years after *** were modeled separately for the 1st and 2nd years to calculate the yearly change in PROms during both follow-up periods with accompanying 95%*** The mean age of the total 500 patients was 62.3 years(standard deviation:10.6)and 202 were male(40%).At a median follow-up of 5.5 years(interquartile range:4.5-6.7),7 patients were deceased and 6 revisions were registered,for infection(n=3),subsidence(n=2)and malposition(n=1).This resulted in an overall 5-year survival of 98.8%(95%CI:97.3-99.5).If infection was left out as reason for revision,a stem survival of 99.4%(95%CI:98.1-99.8)was *** questionnaires were completed by 471 patients(94%),317 patients(63%)completed the 1-year follow-up questionna

关键词： Total hip arthroplasty Femoral stem Short stem Optimys Survival 5-year survival Revision PROms

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Nonaqueous potassium-ion full-cells:mapping the progress and identifying missing puzzle pieces

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Journal of Energy Chemistry 2024年第6期93卷 384-399,I0010页

作者： Badre larhrib louiza larbi lénaïc madec Universite de Pau et des Pays de l’Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Réseau sur le Stockage Electrochimique de l’Energie CNRS FR3459AmiensFrance Institut des matériaux Jean Rouxel(ImN) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

This review addresses the growing interest for potassium-ion full-cells(KIFCs)in view of the transition from potassium-ion half-cells(KIHCs)toward commercial K-ion batteries(KIBs).It focuses on the key parameters of KIFCs such as the electrode/electrolyte interfaces challenge,major barriers,and recent advancements in *** strategies for enhancing KIFC performance,including interfaces co ntrol,electrolyte optimization,electrodes capacity ratio,electrode material screening and electrode design,are *** review highlights the need to evaluate KIBs in full-cell configurations as half-cell results are strongly impacted by the K metal *** also emphasizes the importance of understanding solid electrolyte interphase(SEI)formation in KIFCs and explores promising nonaqueous as well as quasiand all-solid-state electrolytes *** review thus paves the way for practical,cost-effective,and scalable KIBs as energy storage systems by offering insights and guidance for future research.

关键词： K-ion full-cells Potassium-ion batteries Cross-talk Solid-state batteries Potassium reactivity Electrolyte design Electrode design

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low crude protein formulation with supplemental amino acids for its impacts on intestinal health and growth performance of growing-finishing pigs

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1590-1606页

作者： marcos Elias Duarte Wanpuech Parnsen Shihai Zhang marvio l.T.Abreu Sung Woo Kim Department of Animal Science North Carolina State UniversityRaleighNC 27695USA

Background low crude protein(CP)formulations with supplemental amino acids(AA)are used to enhance intestinal health,reduce costs,minimize environmental impact,and maintain growth performance of ***,extensive reduction of dietary CP can compromise growth performance due to limited synthesis of non-essential AA and limited availability of bioactive compounds from protein supplements even when AA requirements are ***,implementing a low CP formulation can increase the net energy(NE)content in feeds causing excessive fat *** supplementation of functional AA,coupled with low CP formulation could further enhance intestinal health and glucose metabolism,improving nitrogen utilization,and growth *** experiments were conducted to evaluate the effects of low CP formulations with supplemental AA on the intestinal health and growth performance of growing-finishing *** In Exp.1,90 pigs(19.7±1.1 kg,45 barrows and 45 gilts)were assigned to 3 treatments:CON(18.0%CP,supplementing lys,met,and Thr),lCP(16.0%CP,supplementing lys,met,Thr,Trp,and Val),and lCPT(16.1%CP,lCP+0.05%SID Trp).In Exp.2,72 pigs(34.2±4.2 kg BW)were assigned to 3 treatments:CON(17.7%CP,meeting the requirements of lys,met,Thr,and Trp);lCP(15.0%CP,meeting lys,Thr,Trp,met,Val,Ile,and Phe);and VlCP(12.8%CP,meeting lys,Thr,Trp,met,Val,Ile,Phe,His,and leu).In Exp.3,72 pigs(54.1±5.9 kg BW)were assigned to 3 treatments and fed experimental diets for 3 phases(grower 2,finishing 1,and finishing 2).Treatments were CON(18.0%,13.8%,12.7%CP for 3 phases;meeting lys,met,Thr,and Trp);lCP(13.5%,11.4%,10.4%CP for 3 phases;meeting lys,Thr,Trp,met,Val,Ile,and Phe);and lCPG(14.1%,12.8%,11.1%CP for 3 phases;lCP+Glu to match SID Glu with CON).All diets had 2.6 mcal/kg *** In Exp.1,overall,the growth performance did not differ among *** lCPT increased(Plaudin-1 expression in the duodenum and *** lCP and lCPT increased(P<0.05)CAT-1,4F2hc,and B0AT exp

关键词： Amino acids Growing-finishing pigs Growth performance Intestinal health low crude protein formulation Net energy

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Distributed swarm control for multi-robot systems inspired by shepherding behaviors

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Science China(Technological Sciences) 2024年第7期67卷 2191-2202页

作者： SUN GuiBin GU HaiBo lÜJinHu School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Zhongguancun laboratory Beijing 100094China

Swarming behaviors play an eminent role in both biological and engineering research, and show great potential applications in many emerging fields. Traditional swarming models still lack integrity, uniformity, and stability in swarm forming processes,resulting in fragmentation and void phenomena. Inspired by the shepherding behaviors observed in nature, we propose an integrated negotiation-control scheme for distributed swarm control of massive robots. The core idea of this scheme is that the robots at the boundary of the group herd the internal robots to form an equilibrium swarm. For this purpose, we introduce a concept of virtual group center towards which boundary robots herd internal robots. Then, a distributed negotiation mechanism is designed to allow each robot to negotiate the virtual group center only through local interactions with its neighbors. After that, we propose a shepherding-inspired swarm control law to drive a group of robots to form an integrated, uniform, and stable configuration from any initial states. Both numerical and flight simulations are presented to verify the effectiveness of our proposed swarm control scheme.

关键词： swarm control multi-robot system negotiation-control scheme shepherding behavior

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Are there sex-based disparities in cataract surgery?

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： matthew D.Geiger Anne m.lynch Alan G.Palestine Nathan C.Grove Karen l.Christopher Richard S.Davidson michael J.Taravella Naresh mandava Jennifer l.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIm:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

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Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai lászló T.mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVl),2-methyltetrahydrofuran(2-meTHF),ionic liquids(Ils),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation Catalysis Solvents Green chemistry Carbon monoxide Transition metals Homogeneous catalysis Palladium

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