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Driving factors behind multiple populations

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun Huang Baitian Tang Chengyuan Li Doug geisler Mario Mateo Ying-Yi Song Holger Baumgardt Julio A.Carballo-Bello Yue Wang Jundan Nie Bruno Dias Joség.Fernández-Trincado School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the guangdong-Hong Kong-Macao greater Bay Area Zhuhai 519082China Departamento de Astronomía Universidad de ConcepcionConcepcionChile Instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile Departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile Department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap Department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada School of Mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia Instituto de Alta Investigación Universidad de TarapacáAricaChile CAS Key laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile Instituto de Astronomía Universidad Católica del NorteAntofagastaChile

Star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical ***,the presence of chemical anomalies in globular clusters(gCs),called multiple stellar populations(MPs),has challenged star formation theories in dense *** studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of *** the limit between clusters with/without MPs in physical parameter space is crucial to reveal the driving mechanism behind their *** this study,we look for MP signals in Whiting 1,which is traditionally considered a young *** the Magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting *** measured the C and N abundances from the CN and CH spectral indices.C and N abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that MPs are absent from Whiting *** these findings with literature studies,we propose a limit in the metallicity *** compactness index parameter space,which relatively clearly separates star clusters with/without MPs(gCs/open clusters).This limit is physically *** a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex *** proposed limit also impacts our understanding of the formation of the Sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for MP formation.

关键词： stellar galactic galaxy

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Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-Cuadrado Iciar Alberdi Isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana López guillermo g.gordaliza María Valbuena-Carabana Nikos Nanos Ramón Perea Luis gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest Competition Recruitment

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NIPT对临床意义不明基因组拷贝数变异的效能评估一项基于28 911例队列的多中心大样本研究

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国际遗传学杂志 2024年第2期47卷 93-105页

作者：杨丽韩锐腊晓琳新疆医科大学第一附属医院生殖医学中心乌鲁木齐生殖疾病与出生缺陷综合防治研究中心乌鲁木齐新疆生殖免疫临床医学研究中心乌鲁木齐新疆医科大学省部共建中亚高发病成因与防治国家重点实验室乌鲁木齐

目的探讨无创产前DNA检测(non-invasive prenatal test, NIPT)在胎儿临床意义不明基因组拷贝数变异(copy number variations, CNVs)中的效能评估, 以期分析NIPT在此类染色体异常筛查中的有效性和可行性。方法回顾性分析2018年1月13日至2... 详细信息

目的探讨无创产前DNA检测(non-invasive prenatal test, NIPT)在胎儿临床意义不明基因组拷贝数变异(copy number variations, CNVs)中的效能评估, 以期分析NIPT在此类染色体异常筛查中的有效性和可行性。方法回顾性分析2018年1月13日至2023年8月30日期间多中心的28 911例单胎孕妇的NIPT筛查结果。NIPT提示临床意义不明CNVs异常信号者, 知情同意后行有创产前诊断进一步做染色体g显带核型分析和基于下一代测序的基因组拷贝数分析(copy number variation sequencing, CNV-seq)检测。并根据CNVs片段大小和胎儿超声结果进一步划分亚组, 以评估NIPT在不同条件下检测临床意义不明CNVs的性能。结果 NIPT共筛查到175例临床意义不明CNVs, 其中108例(66.5%)进一步行产前诊断。经CNV-seq确认后, NIPT筛查临床意义不明CNVs的阳性预测值(positive predictive value, PPV)为25.9%。检测到的CNVs片段大小相差1 Mb范围内的占62.9%。从亚组来看, NIPT筛查效能在颈项透明层(nuchal translucency, NT)增厚组最高(PPV为60.0%), 胎儿超声异常者的PPV高于超声正常组P=0.017。NIPT在<5 Mb(PPV为30.00%)和≥10 Mb(PPV为37.5%)的预测能力较强, 对≥5 Mb且<10 Mb预测能力较弱。在CNVs<5 M且胎儿超声结果正常的情况下, 有13例出现CNVs异常, 除4例自行终止妊娠外, 其余胎儿均无异常。结论 NIPT对临床意义不明CNVs预测能力较低, 并且这类孕妇大多数妊娠结局良好, 特别是对于超声正常的胎儿, 扩大NIPT的检测范围, 可能增加产前诊断率和引起非必要的妊娠终止, 遗传咨询及生育管理至关重要。

关键词：出生缺陷无创产前DNA检测临床意义不明基因组拷贝数变异产前筛查效能评估

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饲粮类型对内蒙古白绒山羊粪尿产污特性的影响

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饲料研究 2024年第9期47卷 12-17页

作者：娜梅拉张晓东娜仁花内蒙古农业大学动物科学学院内蒙古呼和浩特010018

试验旨在探究不同饲粮类型对内蒙古白绒山羊粪、尿产生量,粪尿中有机质、化学需氧量(COD)、氮、磷、铜和锌含量及排放量的影响。选择体重相近的24只8月龄内蒙古白绒山羊母羊为研究对象,随机分成4组,即苜蓿青干草组(g1)、苜蓿青干草补饲... 详细信息

试验旨在探究不同饲粮类型对内蒙古白绒山羊粪、尿产生量,粪尿中有机质、化学需氧量(COD)、氮、磷、铜和锌含量及排放量的影响。选择体重相近的24只8月龄内蒙古白绒山羊母羊为研究对象,随机分成4组,即苜蓿青干草组(g1)、苜蓿青干草补饲精料组(g2)、玉米秸秆组(g3)和玉米秸秆补饲精料组(g4)(补饲组每只羊补饲量200 g,饲粮精粗比为2.5∶7.5,其他饲养条件相同),每组6个重复,每个重复1只羊。预试期为10 d,正式试验期为30 d。结果显示,g2组、g4组鲜粪量显著高于g1组、g3组(Pg1组(Pg1组、g2组内蒙古白绒山羊粪便中铜含量极显著高于g3组、g4组(Pg2组、g4组粪便有机质和锌排放量均显著高于g1组、g3组(Pg3组(Pg2组粪便铜排放量极显著大于其他组(Pg1组和g4组极显著大于g3组(Pg2组尿液中的氮含量及排放量极显著高于其他组(Pg1组、g3组(P<0.05)。研究表明,根据各种饲粮类型所产生的粪尿量及粪尿中污染物排泄规律调控内蒙古白绒山羊饲粮配方,不仅可满足动物的生产需求,还能够降低污染物排泄量。

关键词：饲粮类型粪尿特性内蒙古白绒山羊产粪量产尿量

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PtRu nanoparticles supported on noble carbons for ethanol electrooxidation

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Journal of Energy Chemistry 2022年第3期31卷 168-180,I0006页

作者： Alberto Rodríguez-gómez Enrico Lepre Luz Sánchez-Silva Nieves López-Salas Ana Raquel de la Osa Faculty of Chemical Sciences and Technologies University of Castilla-La ManchaEnrique Costa Novella Building.Avda.Camilo Jose Cela1213071 Ciudad RealSpain Colloid Chemistry Department Max Planck Institute of Colloids and InterfacesAm Mühlenberg 114476 PotsdamGermany

In this work,three cytosine derived nitrogen doped carbonaceous materials(noble carbons,NCs)with different atomic C/N ratios and porous networks have been synthesized and used as supports for Pt Ru electrocatalysts in the ethanol oxidation reaction(EOR)for clean hydrogen ***,the metal phase and the carbon support play critical roles in the electrocatalysts final *** NPs size distribution was obtained over supports with low atomic C/N ratios(i.e.,4 and 6)and defined porosity(i.e.,1701 m^(2)g^(-1)for Pt Ru/CNZ and 1834 m^(2)g^(-1)for Pt Ru/CLZ,respectively).In contrast,a lower C/N ratio and poor porous network(i.e.,65 m^(2)g^(-1),Pt Ru/CLK)led to the largest particle size and fostered an increase of the alloying degree between Pt and Ru NPs(i.e.,3%for C/N~6 and 28%for C/N~3).Electrochemical active surface area was found to increase with decreasing NPs size and the alloy extent,due to a higher availability of Pt active *** degradation tests showed that Pt Ru/NCs outperform similar to Pt Ru NPs on commercial carbon pointing at the stabilizing effect of *** Ru/CNZ exhibited the best electrochemical performance(i.e.,69.1 m A mgPt-1),outperforming Pt Ru/CLZ and Pt Ru/CLK by3-and 9-fold,respectively,due to a suitable compromise between particle sizes,degree of alloy,textural properties and elemental *** anodes were scaled-up to a proton exchange membrane cell and Pt Ru/CNZ was proved to provide the best electrocatalytic activity(262 m A cm^(-2)and low energy requirements),matching the values obtained by the state of the art of EOR electrocatalysts.

关键词： Noble carbon Cytosine H2 production Ethanol electrooxidation PtRu anode PEM cell

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纯钨表面等离子Ta合金层耐腐蚀性能研究

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热加工工艺 2024年第2期53卷 97-99,104页

作者：薛海龙赵鹏飞剌玲敏秦林太原理工大学新型碳材料研究院山西太原030024

利用双层辉光等离子表面合金化技术在纯钨表面制备Ta合金化改性层以改善材料的耐腐蚀性。研究不同温度工艺参数对Ta合金层组织结构及耐腐蚀性能的影响。结果表明:在不同温度工艺参数下均制备出连续致密的Ta合金化改性层,且随温度升高,... 详细信息

利用双层辉光等离子表面合金化技术在纯钨表面制备Ta合金化改性层以改善材料的耐腐蚀性。研究不同温度工艺参数对Ta合金层组织结构及耐腐蚀性能的影响。结果表明:在不同温度工艺参数下均制备出连续致密的Ta合金化改性层,且随温度升高,合金层的厚度增加。合金层主要由纯Ta相组成。Ta合金层的自腐蚀电位高于基材的,而自腐蚀电流密度较低,即Ta合金层更难以发生电化学腐蚀反应且腐蚀速率更低。900℃合金层的耐蚀性能最佳,腐蚀速率降至8.45×10^(-3)g·m^(-2)·h^(-1),表现出优良的耐腐蚀性。

关键词：纯钨基材 Ta合金化改性层双辉等离子表面合金化技术耐蚀性

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Role of vascular endothelial growth factor as a critical neurotrophic factor for the survival and physiology of motoneurons

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Neural Regeneration Research 2023年第8期18卷 1691-1696页

作者： Paula M.Calvo Rosendo g.Hernández Rosa R.de la Cruz Angel M.Pastor Departamento de Fisiología Facultad de BiologíaUniversidad de SevillaSevillaSpain

Vascular endothelial growth factor(VEgF)was discovered by its angiogenic ***,during evolution,it appeared earlier as a neurotrophic factor required for the development of the nervous system in invertebrates lacking a circulatory *** aimed at reviewing recent evidence indicating that VEgF has neuroprotective effects in neurons exposed to a variety of *** particular interest is the link established between VEgF and motoneurons,especially after the design of the VEgFδ/δmutant *** mice are characterized by low levels of VEgF and develop muscle weakness and motoneuron degeneration resembling amyotrophic lateral *** administration of VEgF through several routes to animal models of amyotrophic lateral sclerosis delays motor impairment and motoneuron degeneration and increases life *** are new recent advances in the role of VEgF in the physiology of *** experimental aims use the extraocular(abducens)motoneurons lesioned by axotomy as a model for studying VEgF *** abducens motoneurons exhibit severe alterations in their discharge activity and a loss of synaptic *** exogenous administration of VEgF to axotomized abducens motoneurons,either from the transected nerve or intraventricularly,fully restores the synaptic and discharge properties of abducens motoneurons,despite being *** addition,when an anti-VEgF neutralizing antibody is delivered from the muscle to intact,uninjured abducens motoneurons,these cells display alterations in their discharge pattern and a loss of synaptic boutons that resemble the state of *** these data indicate that VEgF is an essential neurotrophic factor for motoneurons.

关键词： abducens nucleus amyotrophic lateral sclerosis cell death extracellular single-unit recordings eye movements neurodegeneration oculomotor trophic factors

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决明子提取物对牦牛肉肌原纤维蛋白氧化稳定性的影响

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食品科技 2024年第7期49卷 122-128页

作者：李国昊祖拉毕秀芳黄梅桂郝刚西南民族大学食品科学与技术学院四川成都610041

文章探讨了在氧化体系中,浓度0~2000μg/m L决明子提取物对牦牛肉肌原纤维蛋白氧化稳定性的影响。结果表明,随着决明子提取物浓度的增加,羰基含量、表面疏水性、自由氨基、二聚酪氨酸含量、内源性荧光均显著下降(P<0.05),巯基含量显著上... 详细信息

文章探讨了在氧化体系中,浓度0~2000μg/m L决明子提取物对牦牛肉肌原纤维蛋白氧化稳定性的影响。结果表明,随着决明子提取物浓度的增加,羰基含量、表面疏水性、自由氨基、二聚酪氨酸含量、内源性荧光均显著下降(Pg/m L)的α-螺旋、β-折叠、β-转角总量提升了10%,无规则卷曲含量下降了11%;高浓度决明子提取物处理组(≥1000μg/m L)相较于600μg/m L处理组,α-螺旋、β-转角、β-折叠总量降低了10%。综上可得,决明子提取物能够有效地抑制牦牛肉的蛋白质氧化,较好地维持蛋白空间结构,对牦牛肉肌原纤维蛋白具有保护作用,且效果与浓度相关。

关键词：决明子提取物牦牛肉肌原纤维蛋白氧化稳定性

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Construction of a novel six-gene signature to predict tumour response to induction chemotherapy and overall survival in locoregionally advanced laryngeal and hypopharyngeal carcinoma

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genes & Diseases 2024年第3期11卷 148-150页

作者： Chen Tan Lingwa Wang Yifan Yang Shizhi He george g.Chen Jason YK.Chan Michael CF.Tong C.A.van Hasselt Wenbin Xu Ling Feng Ru Wang Jugao Fang Department of Otolaryngology Head and Neck Surgery Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Key laboratory of Otolaryngology Head and Neck Surgery(Ministry of Education of China) Beijing Institute of OtolaryngologyBeijing 100730China Department of Otorhinolaryngology Head and Neck SurgeryThe Chinese University of Hong KongPrince of Wales HospitalHongKong SAR999077China Department of Medical genetics Institute of Basic Medical ScienceChinese Academy of Medical Science&Peking Union Medical CollageBeijing 100730China

Locoregionally advanced laryngeal and hypopharyngeal cancers(la-LHCs)are traditionally treated with surgery followed by postoperative radiotherapy,which impairs speech and swallowing functions and reduces the quality of life.^(1,2)The use of induction chemotherapy(IC)as a larynxpreserving approach for la-LHCs has been verified and refined.^(3)However,the short-term tumor response to IC varies,non-responders usually show poor survival and little benefit.

关键词： chemotherapy laryngeal surgery

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Digestive Surgical Emergencies at the “Mother Child”Hospital Center Luxembourg in Mali

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Surgical Science 2024年第5期15卷 299-310页

作者： Cheickna Tounkara Amara Coulibaly Yaya Ongoiba Aboubakrine Sylla Abdoul Karim Simaga Bréhima B. Coulibaly Aminata Dabo Souleymane Dembele Samake Hamidou Sidiki Keita Sékou Bréhima Koumare Soumaïla Keita Bakary Tientigui Dembele Zimogo Zié Sanogo Djibril Sangare Department of general Surgery and Anesthesia-Resuscitation of the “ Mother Child&#8221 Hospital Center Luxembourg Bamako Mali Social Health Service of the Armed Forces of Mali Bamako Mali Department of general Surgery “ A&#8221 and Cardiovascular of Point G University Hospital Bamako Mali Department of general Surgery of CHU gabriel TOURE Bamako Mali

Digestive surgical emergencies concern all patients admitted urgently, for whom a decision for surgical intervention may be necessary within 24 hours. They are on guard duty day and night. To carry out this work, we set ourselves the objectives of: 1) Studying digestive surgical emergencies in the general surgery department of the “Mother Child” Le Luxembourg hospital in Bamako, Mali;2) Determine the frequency of digestive surgical emergencies, 3) Describe the clinical and therapeutic aspects, and 4) Analyze the results of treatment. From November 1, 2022 to October 31, 2023, the general surgery department of the “Mother Child” Luxembourg Hospital Center in Bamako, Mali, carried out 139 digestive surgical emergencies whose files were usable;75 men and 64 women, a sex ratio of 1.2. The 20 - 40 years old age group was the most represented, at 40.29%. The average age was 39 years;the extremes 16 years and 93 years with a standard deviation of 21.65 years. The reference concerned 51.08% of our patients. Abdominal pain was the main reason for consultation (100% of cases). In the majority of cases, the physical examination made it possible to make the diagnosis. Faced with certain clinical cases, we requested ultrasound (109/139), ASP (46/139) and CT (15/139). The main etiology was acute appendicitis with 42.45% of cases. The frequency of digestive surgical emergencies was 10.71% of all activities in the general surgery department of the “Mère Enfant” Le Luxembourg hospital center in Bamako. All our patients were seen in consultation by an anesthesiologist before entering the operating room. The surgical consequences were complicated in 11.51% of cases with 7.91% deaths. Surgical site infections accounted for 12.5% of postoperative complications. Eleven deaths were noted, representing 68.75% of complications and 7.91% of our sample. Acute peritonitis was the cause of death in 100% of cases. The average cost of care was 329,000 FCFA.

关键词： Emergency Digestive Surgery Post-Operative Complication

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