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collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia P.Loiseau P.Forestier-colleoni M.Tarisien E.Atukpor V.bagnoud c.brabetz F.consoli J.Domange F.Hannachi P.Nicolaï M.Salvadori b.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance cEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance cENbG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly cELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(cSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for cSA.

关键词： acceleration hydrodynamic collision

深圳市24家医院极/超早产儿产房过渡期管理的横断面调查

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中国当代儿科杂志 2024年第3期26卷 250-257页

作者：无吴本清杨传忠深圳新生儿数据协作网深圳市光明区人民医院深圳市妇幼保健院

目的了解深圳市极/超早产儿产房过渡期管理实施现状。方法2022年11月对深圳新生儿数据协作网的24家三级医院的极/超早产儿产房过渡期管理实施情况进行横断面调查,调查内容包括产前准备、产房复苏实施和新生儿重症监护室复苏后管理。根... 详细信息

目的了解深圳市极/超早产儿产房过渡期管理实施现状。方法2022年11月对深圳新生儿数据协作网的24家三级医院的极/超早产儿产房过渡期管理实施情况进行横断面调查,调查内容包括产前准备、产房复苏实施和新生儿重症监护室复苏后管理。根据胎龄将所纳入早产儿分为4组:<26周、26~28^(+6)周、29~30^(+6)周和31~31^(+6)周组,对结果进行描述性分析。结果共纳入140例极/超早产儿,其中<26周组10例,26~28^(+6)周组45例,29~30^(+6)周组49例,31~31^(+6)周组36例。140例极/超早产儿中,99例(70.7%)接受了产前咨询,提供产前咨询的人员以产科医生为主,占比为79.8%;产时参与复苏的人员主要为助产士(96.4%)和新生儿科住院医师(62.1%);52例(37.1%)实施了延迟脐带结扎,平均延迟时间为(45±17)s;137例(97.9%)生后采用了预热辐射台保暖;110例(78.6%)需要正压通气,其中67例(60.9%)采用T组合复苏器,42例(38.2%)应用了空氧混合仪;119例(85.0%)复苏中进行了血氧饱和度监测;完成过渡期各项措施至关闭温箱门时间的中位数为87min。结论在深圳新生儿数据协作网医院中,极/超早产儿的产房过渡期管理实施与我国相应专家共识的要求存在不同程度的差异,需要通过多中心协作的持续质量改进缩小差距,从而改善极/超早产儿产房过渡期管理的质量和结局。

关键词：过渡期管理横断面调查深圳极早产儿超早产儿

Gustatory responsiveness in Vespula germanica workers:exploring the interplay between sensory perception and task specialization

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Insect Science 2024年第2期31卷 587-598页

作者： Analia Mattiacci carolina Mengoni Gonalons MaitéMasciocchi Juan c.corley Grupo de Ecologia de Poblaciones de Insectos IFAB(CONICETINTA EEA Bariloche)BarilocheArgentina Departamento de Ecologia Centro Regional Universitario BarilocheUniversidad Nacional Del ComahueBarilocheArgentina Departamento de biodiversidad y biologia Experimental Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina

Workers'task specialization and division of labor are critical features of social insects'ecological *** has been proposed that the division of labor relies on response threshold models:individuals varying their sensitivity(and responsiveness)to biologically relevant stimuli and performing a specific task when a stimulus exceeds an internal *** this work,we study carbohydrate and protein responsiveness and their relation to worker task specialization in Vespula germanica,an invasive social *** sucrose and peptone responsiveness of two different subcastes,preforagers and foragers,was determined by stimulating the antenna of the wasps with increasing concentrations of the solution and quantifying whether each concentration elicited a licking *** studied responsiveness in five different ways:(1)response threshold,(2)concentration 50(concentration to which at least 50%of wasps responded),(3)maximum response,(4)mean scores and(5)median *** results suggest that V germanica foragers are more sensitive to sucrose(lower thresholds)than preforager ***,we found no differences for peptone thresholds(i.e.,a protein resource).Nonetheless,this is the first study to investigate response thresholds for protein *** intercaste variation in sucrose responsiveness shown in our work contributes to the existing knowledge about response threshold theory as a mechanism for task specialization observed in V germanica.

关键词： carbohydrates responsiveness division of labor protein responsiveness response thresholds models social insect yellow jacket

Investigation of HcAR2 antagonists as a potential strategy to modulate bovine leukocytes

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Journal of Animal Science and biotechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby c.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua Evan c.Titgemeyer barry J.bradford Department of Animal Science Michigan State UniversityEast LansingMichigan 48824USA Department of Animal Sciences and Industry Kansas State UniversityManhattanKS 66506USA comparative Medicine and Integrative biology East LansingMI 48824USA Department of chemistry Kansas State UniversityManhattanKS 66506USA

background Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid(bHbA;the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. bHbA is a ligand of HcAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The objective of this study was to identify and test antagonists for HcAR2 in bovine immune cells cultured with *** We observed expression of HcAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HcAR2 tended to be greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and b cells expressing HcAR2. Stimulation of HcAR2 with niacin or bHbA promoted ca^(2+) mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with bHbA had diminished intracellular ca^(2+) responses when HcAR2 was knocked down by si RNA silencing, indicating ca^(2+) mobilization was mediated by HcAR2 signaling. Two candidate antagonists for HcAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced ca^(2+) mobilization after incubation with bHbA. Furthermore, NA-5 but not NA-1 prevented bHbA-associated reductions in cyclic *** We demonstrated that HcAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that bHbA and niacin derived HcAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both bHbA and niacin affect bovine leukocyte ca^(2+) mobilization in a HcAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis

Hydroelectrolytic and Energetic Replenisher in Horses Undergoing Marcha Training

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Open Journal of Veterinary Medicine 2024年第8期14卷 203-216页

作者： José D. Ribeiro Filho bruna M. Ribeiro Micheline O. Silva Samuel R. Alves Anaïs c. benitez Waleska M. F. Dantas Marcel F. b. Avanza Raffaella b. c. Teixeira Pedro Ancelmo N. Ermita Laice A. Silva Rinaldo b. Viana Hélio c. Manso Filho Department of Veterinary Federal University of Viosa Viosa Brazil Institute of Studies of the Wet Tropic Federal University of Southern and Southeastern Par Xinguara Brazil Department of Veterinary clinic and Surgery Federal University of Minas Gerais Belo Horizonte Brazil Institute of Animal Health and Production Federal Rural University of Amazonia Belm Brazil Zootecnics Department Federal Rural University of Pernambuco Recife Brazil

The study aimed to assess the clinical, laboratory, and blood gas analysis of horses undergoing Marcha training and the effects of voluntary ingestion of hydroelectrolytic and energy replenishers after exercise. Eight horses of both genders aged between 5 and 10 years, were included in the study. The exercise consisted of a 10-min warm-up followed by 45 min uninterrupted Marcha on a flat dirt track in the morning. After exercise, the horses received one of the following treatments: Drinking water (control group);Hydroelectrolytic and energy replenisher containing sodium chloride, potassium chloride, calcium acetate, magnesium chloride, sodium citrate, dextrose, maltodextrin, and sucrose in three different concentrations (Replenishers A, b, and c). The horses were distributed across the four treatments in a 4 × 4 Latin Squares design using a Split-plot system with 48-hr intervals. clinical and laboratory evaluations were conducted at four time points: T0 - 5 min before exercise;T1 - up to 5 min after exercise;T2 - 2 hr after starting treatment;and T4 - 4 hr after beginning treatment. concentrations of urea, creatinine, lactate, phosphorus, and ionized calcium significantly changed after exercise. An increase in blood pH and a decrease in chloride concentrations were observed when replenishers b and c were offered after exercise. The replacements were ingested spontaneously by the animals in a volume greater than that of the control group (water). Replacement b was the most ingested by the animals, demonstrating its greatest potential.

关键词： Dehydration Electrolyte Replacement Exercise Rehydration Voluntary Intake

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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chinese Physics c 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.Fedorov S.b.Dabylova Yu.N.Kopatch I.N.Ruskov V.R.Skoy T.Yu.Tretyakova c.Hramco P.I.Kharlamov G.V.Pampushik P.G.Filonchik A.V.Andreev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan Skobeltsyn Institute of Nuclear Physics Moscow State UniversityMoscowRussia Institute of chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite bi_(4)Ge_(3)O_(12)(bGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

n-Alkane bound biomarker fingerprints from asphaltenes in the bitumens of Eastern Dahomey basin,Nigeria:Source and genetic implications

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Petroleum Research 2024年第1期9卷 85-91页

作者： Modupe A.Egbeola Olubunmi c.Adeigbe Olajide J.Adamolekun Department of Geology University of IbadanIbadanNigeria Structural Geology and Tectonics Institute of Applied GeosciencesKIT-Karlsruhe Institute of TechnologyAdenauerring 20a76131KarlsruheGermany

The asphaltene fractions of the bitumens of Eastern Dahomey basin in Nigeria,were analyzed by flash pyrolysis-gas chromatography(Py-Gc)method in order to unravel its geochemical history and *** distributions of the initial biomarkers of the original oils from the pyrolysates are related to the assessment of organic matter source,paleo-redox conditions and source environment during ***,it effectively establishes the genetic relationship of the *** n-alkane distributions in the pyrolysates reveal nc_(9)-nc_(32)n-alkanes,maximizing at nc_(14),isoprenoids-pristane(Pr)and phytane(Ph),and some n-alkene *** peaks of low to medium-weight nc_(9)-nc20 n-alkanes and low peaks of nc_(21)+n-alkanes characterize the *** reveal that abundant algal organic matter with some terrigenous inputs contributed to the source rock of the *** high concentration of marine organic matter inputs to the source rock is further confirmed by the nc_(17)/nc27 ratios which range from 5.39 to 19.82 and shows the predominance of nc_(17)*** general unimodal n-alkane distributions in the bitumens indicate derivation from similar organic matter types showing that they are genetically *** anoxic to suboxic environmental conditions that prevailed during the deposition of the sediments is revealed by the isoprenoids,Pr/Ph ratios(0.72-1.28).Pristane/nc_(17)and Phytane/nc_(18)range from 0.16 to 0.33 and 0.22 to 0.56,revealing that the bitumens were from predominantly marine organic matter(type II kerogen)preserved in a reducing environment with no evidence of ***,the Ph/nc_(18)ratio and the cross plot of Pr+Ph/nc_(17)+nc_(18)allow the classification of the bitumens into two subfamilies/groups(A and b).The bitumen samples have low wax content as indicated by the degree of waxiness ranging from 0.21 to 0.38 which confirms low terrigenous *** on the carbon preference index(cPI:0.92 to 1.55)and odd-even predo

关键词： Genetic relationship Flash pyrolysis biomarker Asphaltene Pyrolysates

Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution position and strength of the donors

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Science china chemistry 2024年第5期67卷 1613-1623页

作者： changfeng Si Dianming Sun Tomas Matulaitis David b.cordes Alexandra M.Z.Slawin Eli Zysman-colman Organic Semiconductor centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2Gcz bP, 2DPAcz bP, 2FbP2Gcz and 2FbP2DPAcz. We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant(kRISc) of the emitters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(bP) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. compound 2DPAcz bP, containing stronger donors than 2Gcz bP, exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPAcz bP doped in m cP emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4cz IPN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DPAcz bP HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrimers

Gut microbiota in preterm infants receiving breast milk or mixed feeding

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World Journal of clinical Pediatrics 2024年第2期13卷 135-145页

作者： Sandra Gabriela Sánchez-González bárbara Gabriela cárdenas-del-castillo Elvira Garza-González Gerardo R Padilla-Rivas Isaías Rodríguez-balderrama consuelo Treviño-Garza Fernando Félix Montes-Tapia Gerardo c Palacios-Saucedo Anthony Gutiérrez-Rodríguez Manuel Enrique de-la-O-cavazos Department of Pediatrics Hospital Universitario“Dr.JoséEleuterio González”Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Departamento de bioquímica y Medicina Molecular Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Department of biochemistry and Molecular Medicine Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Department of Pediatric Surgery Hospital Universitario"Dr.JoséEleuterio González"Monterrey 64460Nuevo LeónMéxico

bAcKGROUND Preterm birth is the leading cause of mortality in newborns,with very-low-birthweight infants usually experiencing several *** milk is considered the gold standard of nutrition,especially for preterm infants with delayed gut colonization,because it contains beneficial microorganisms,such as Lactobacilli and *** To analyze the gut microbiota of breastfed preterm infants with a birth weight of 1500 g or *** An observational study was performed on preterm infants with up to 36.6 wk of gestation and a birth weight of 1500 g or less,born at the University Hospital ***éEleuterio González at Monterrey,Mexico.A total of 40 preterm neonates were classified into breast milk feeding(bM)and mixed feeding(MF)groups(21 in the bM group and 19 in the MF group),from October 2017 to June *** samples were collected before they were introduced to any feeding *** full enteral feeding was achieved,the composition of the gut microbiota was analyzed using 16S rRNA gene *** variables were compared using Student’s t-test or using the Mann–Whitney U test for nonparametric ***,evenness,equitability,Margalef’s index,Fisher’s alpha,chao-1 index,and Shannon’s diversity index were also *** No significant differences were observed at the genus level between the *** comparison indicated higher counts of Alphaproteobacteria and betaproteobacteria in the initial compared to the final sample of the bM group(Pcounts of Gammaproteobacteria were detected in the final than in the initial sample(P=0.040).According to the Margalef index,Fisher’s alpha,and chao-1 index,a decrease in species richness from the initial to the final sample,regardless of the feeding type,was observed(Pbacteroidetes,Actinobacteria,Firmicutes,and Proteobacteria,with Proteobacteria being the most ***,no significant differences were

关键词： Gut microbiota Human milk Preterm infant Proteobacteria Very low birth weight 16S rRNA