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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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journal of Mountain Science 2024年第1期21卷 146-159页

作者： hAO Aihua LUO Zhengming chen Xiaojiang Department of geography Xinzhou Normal UniversityXinzhou 034000China Department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. however, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(Phe percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p h, NO_(3)^(-)-N, or Nh_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(Phannon-Weiner index(Pgradients but significantly decreased belowground biomass(Ph of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(Pgnificant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

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青藏高原及其周边侏罗纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1211-1243页

作者：李建国饶馨牟林崔肖辉李鑫罗辉刘培学中国科学院南京地质古生物研究所中国科学院生物演化与环境卓越创新中心南京210008 中国科学院大学南京学院南京211135

侏罗纪是青藏高原构造演化的重要阶段,它结束了古特提斯构造演化,即将迎来印度板块的向北漂移和新特提斯的消减.地层时代是地质历史重建的基础.本文对近年来所取得的一些地层学、古生物新发现和新进展进行了综合和梳理,为青藏高原侏罗... 详细信息

侏罗纪是青藏高原构造演化的重要阶段,它结束了古特提斯构造演化,即将迎来印度板块的向北漂移和新特提斯的消减.地层时代是地质历史重建的基础.本文对近年来所取得的一些地层学、古生物新发现和新进展进行了综合和梳理,为青藏高原侏罗系建立了一个新的多重地层划分对比和时代框架.该框架包括巴颜喀拉、羌塘、拉萨-冈底斯和藏南喜马拉雅四个分区.其中,综合生物地层框架得到了很大的补充和细化,包括了一系列在青藏高原侏罗系中常见并在国际侏罗系划分对比中具有重要作用的化石门类,如海相的菊石、双壳、腕足、放射虫、有孔虫和沟鞭藻以及陆相的孢子花粉和轮藻等.通过菊石标准分子或特征属种,建立了该生物地层框架与国际地层委员会2020年侏罗纪地质年表(gTS 2020)的标准分带的对比.以此为基础,建立了青藏高原主要区块间侏罗系的横向对比.生物群对比揭示,侏罗纪时拉萨-冈底斯区与羌塘区的关系比与藏南喜马拉雅更紧密,它们总体属于东特提斯洋北缘海区同一个特征相似的生物地理区系,不太支持雅鲁藏布江缝合带特提斯是弧后小盆地的观点.综合地层、生物和沉积特征,研究认为,班公湖-怒江特提斯在晚三叠世开始张裂,可能在早侏罗世晚期已有初始洋壳增生形成;中侏罗世晚期班公湖-怒江洋发展至顶峰,随后开始收缩,羌塘地块向南俯冲与拉萨-冈底斯地块发生碰撞和拼合.

关键词：生物地层年代地层特提斯雅鲁藏布缝合带班公湖-怒江缝合带

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儿童急性局灶性细菌性肾炎的诊疗现状

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中华儿科杂志 2024年第5期62卷 486-489页

作者：陈瑜余自华福建省儿童医院肾脏风湿免疫科福建医科大学妇儿临床医学院福州350014

急性局灶性细菌性肾炎(AFBN)是一种局限于肾实质的细菌性感染。AFBN临床表现缺乏特异性;其影像学特征是肾脏超声显示肾实质内局灶性病变、皮髓质分界不清,增强CT示肾实质内楔形低密度灶,病变在增强MRI的T2W呈低信号、增强后T1W呈低强化... 详细信息

急性局灶性细菌性肾炎(AFBN)是一种局限于肾实质的细菌性感染。AFBN临床表现缺乏特异性;其影像学特征是肾脏超声显示肾实质内局灶性病变、皮髓质分界不清,增强CT示肾实质内楔形低密度灶,病变在增强MRI的T2W呈低信号、增强后T1W呈低强化。当急性肾盂肾炎患儿经抗菌药物治疗后发热持续时间≥48 h、白细胞尿持续时间超过4 d、血清白细胞介素6、干扰素γ显著增高时要疑诊AFBN;若发现AFBN影像学特征性改变,则可诊断为AFBN。AFBN的抗菌药物疗程至少为3周。

关键词：急性肾盂肾炎肾实质局灶性病变发热持续时间低密度灶诊疗现状增强MRI 细菌性感染

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Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

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International journal of Minerals,Metallurgy and Materials 2024年第1期31卷 206-215页

作者： Baoshan Xie huan Ma Chuanchang Li jian chen Key Laboratory of Renewable Energy Electric-Technology of hunan Province School of Energy and Power EngineeringChangsha University of Science and TechnologyChangsha 410114China State Key Laboratory of Disaster Prevention and Reduction for Power grid Changsha University of Science and TechnologyChangsha 410114China

Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building *** coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite *** prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (Eg) as an *** combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading *** showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface *** loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% *** data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed *** obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 j·g^(-1),and good chemical *** SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.

关键词： thermal energy storage phase change material stone coal vanadium extraction secondary utilization

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一种用于多核磁共振成像及波谱的鸟笼线圈与可更换单环线圈的一体化设计（英文）

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journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第2期 168-181页

作者：张怡全枝艳楼飞洋方玉娇 garth j.ThOMPSON 陈高张孝通浙江大学医学院附属第二医院神经外科浙江省神经外科疾病精准诊治及临床转化重点实验室浙江大学教育部脑与脑机融合前沿科学中心浙江大学系统神经与认知科学研究所浙江大学医学院上海科技大学ihuman研究所浙江大学电气工程学院

能量代谢对生命活动至关重要，主要包括对碳水化合物、脂肪和蛋白质的利用过程，异常的能量代谢与诸多疾病密切相关。本研究提出了一种用于多核磁共振成像(MRI)与波谱(MRS)的射频线圈设计：通过3D打印线圈外壳和支架，将一个鸟笼1h线圈... 详细信息

能量代谢对生命活动至关重要，主要包括对碳水化合物、脂肪和蛋白质的利用过程，异常的能量代谢与诸多疾病密切相关。本研究提出了一种用于多核磁共振成像(MRI)与波谱(MRS)的射频线圈设计：通过3D打印线圈外壳和支架，将一个鸟笼1h线圈和可更换的单环X核(2h、13C、23Na和31P)线圈一体化集成，其中单环线圈通过一个弧形支架安装于鸟笼线圈内壁，使其可沿内壁轴向无阻碍地移动，方便实现成像实验中多核线圈的更换以及线圈相对于不同成像体的摆放。与商用鸟笼1h核线圈相比，本设计具有更好的1h信号激发均匀性和成像信噪比；小鼠的活体实验验证了线圈设计在成像与波谱研究方面的可行性与有效性，可同时满足结构成像和能量代谢检测的要求。综上所述，该多核线圈通过新型机械与电路设计可以简化多核磁共振成像能量代谢检测的实施过程。

关键词：能量代谢核磁共振成像磁共振波谱多核射频线圈 3D打印

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Discovery of new MAX-phase-like layered ternary carbide V_(8)P_(6)C:Crystal structure,thermal expansion,and elastic properties

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journal of Materials Science & Technology 2024年第7期174卷 55-62页

作者： h.X.chen L.Sheng Z.L.Zhang X.C.Wen D.L.Yang X.Y.Ye P.Q.Dai School of Materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application Fuzhou 350118China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the laminated structure,MAX phases and MAX-phase-like compounds possess outstanding dam-age tolerance capability with good thermal/electrical conductivity and other charming functional prop-erties,showing a bright future for structural-functional ***,a new MAX-phase-like ternary car-bide V_(8)P_(6)C with layered characteristics was *** to the alternate stacking of hexagonal-arranged M/A/X atom layers in MAX phases,V_(8)P_(6)C has a layered structure formed by a repeated stacking of the slabs consisting of V_(6)C-octahedrons and VP 6-distorted-octahedrons in three-atomic layers *** thermal expansion anisotropy was revealed,with the thermal expansion coefficients(TECs)along a-axis,c-axis,and the average value,equal toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(L)=9.14(5)μK^(−1),*** dilation along the c-axis was mainly dominated by out-plane V-P bonds be-tween layered *** to the pressure-dependent lattice parameters,the polycrystalline bulk modulus(B_(0)=185(9)gPa)and high compressibility anisotropy factor(B_(a)/B_(c)=1.64)was ***-while,the second-order elastic constants were calculated,and the elastic moduli,E=303 gPa,B=198 gPa,g=122 gPa,andν=0.246,were *** the weak connection between layer slabs by out-plane V1-P bond was revealed by the bond stiffness model,with a bond stiffness close to the M-A bond in MAX ***,good damage tolerance capability was predicted according to Paugh’s ratio(g/B=0.616)and Cauchy pressure(P_(a)=0 gPa,P_(c)=-7.5 gPa),even better than those of typical MAX *** discovery of V_(8)P_(6)C provides a new member of MAX-phase-like damage-tolerant ceramic with relatively low density,moderate thermal expansion,and anisotropic compressibility,and the unique lay-ered structure is inspiring for exploring new layered ternary ceramics.

关键词： New ternary carbide MAX phase Thermal expansion Elastic constants Anisotropy

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Desialylated Platelet Clearance in the Liver is a Novel Mechanism of Systemic Immunosuppression

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Research 2024年第3期2023卷 35-50页

作者： june Li Danielle Karakas Feng Xue Yingyu chen guangheng Zhu Yeni h.Yucel Sonya A.MacParland haibo Zhang john W.Semple john Freedman Qizhen Shi heyu Ni Department of Laboratory Medicine and Pathobiology University of TorontoTorontoONCanada Toronto Platelet Immunobiology group TorontoONCanada Keenan Research Centre for Biomedical Science of St.Michael's hospital TorontoONCanada Canadian Blood Services Centre for Innovation TorontoONCanada Departments of Pediatrics Medical College of WisconsinMilwaukeeWIUSA Blood Research Institute Versiti WisconsinMilwaukeeWIUSA Departments of Ophthalmology and Vision Sciences Medicine University of TorontoTorontoONCanada Faculty of Engineering and Architectural Science Ryerson UniversityTorontoONCanada Multi-Organ Transplant Program Toronto General Hospital Research InstituteTorontoONCanada Department of Immunology University of TorontoTorontoONCanada Critical Care Medicine Department ofAnesthesiology and PainUniversity of TorontoTorontoONCanada Department of Physiology University of TorontoTorontoONCanada Department of Pharmacology University of TorontoTorontoONCanada. Division of hematology and Transfusion Medicine Lund UniversityLundSweden clinical Immunology and Transfusion Medicine Ofice of Medical ServicesRegion SkaneLundSweden Department of Medicine University of TorontoTorontoONCanada Children's Research Institute Children's WisconsinWauwatosaWIUSA Midwest Athletes Against Childhood Cancer Fund Research Center MilwaukeeWIUSA.

Platelets are small, versatile blood cells that are critical for hemostasis/thrombosis. Local platelet accumulation is a known contributor to proinflammation in various disease states. however, the anti-inflammatory/immunosuppressive potential of platelets has been poorly explored. here, we uncovered, unexpectedly, desialylated platelets (dPLTs) down-regulated immune responses against both platelet-associated and -independent antigen challenges. Utilizing multispectral photoacoustic tomography, we tracked dPLT trafficking to gut vasculature and an exclusive Kupffer cell-mediated dPLT clearance in the liver, a process that we identified to be synergistically dependent on platelet glycoprotein Ibα and hepatic Ashwell–Morell receptor. Mechanistically, Kupffer cell clearance of dPLT potentiated a systemic immunosuppressive state with increased anti-inflammatory cytokines and circulating CD4+ regulatory T cells, abolishable by Kupffer cell depletion. Last, in a clinically relevant model of hemophilia A, presensitization with dPLT attenuated anti-factor VIII antibody production after factor VIII ( infusion. As platelet desialylation commonly occurs in daily-aged and activated platelets, these findings open new avenues toward understanding immune homeostasis and potentiate the therapeutic potential of dPLT and engineered dPLT transfusions in controlling autoimmune and alloimmune diseases.

关键词： Platelet transfusion homeostasis

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Leflunomide: A versatile additive for defect reduction, enhanced optoelectronic properties and environmental stability of perovskite films

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Nano Research 2024年第4期17卷 2628-2637页

作者： Dingyue Sun Ming Peng Taijin Wang Longju Yi Shizuo Zhang Feng Liu gary j.cheng The Institute of Technological Sciences Wuhan UniversityWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China School of Industrial Engineering Purdue UniversityWest LafayetteIN 47906USA

The development of perovskite photoelectric devices with excellent performance is largely dependent on the defects in the perovskite *** address this issue,a specific drug,leflunomide(LF,C_(12)h_(9)F_(3)N_(2)O_(2)),was incorporated into the perovskite to reduce defects and improve its photoelectric *** is believed that the C=O bond on LF molecule can interact with the uncoordinated Pb2+of the perovskite,thereby reducing non-radiative *** novel approach of incorporating LF into perovskite films has the potential to revolutionize the development of high-performance perovskite photoelectric *** trifluoromethyl functional(–CF_(3))group on LF can form a protective layer on the surface of the perovskite film,shielding it from water ***,LF can be utilized to alter the nucleation position of perovskite,thus minimizing the number of defects and optimizing the film ***,the LF-doped perovskite film displays low trap density and high photoelectric *** LF-doped perovskite film showed a trap density of 8.28×10^(11),which is notably lower than the 2.04×10^(12) of the perovskite film without *** responsivity and detectivity of the LF-doped perovskite photodetector were 0.771 A/W and 2.81×10^(11) jones,respectively,which are much higher than the 0.23 A/W and 1.06×10^(10) jones of the LF-undoped perovskite ***,the LF-doped photodetector maintained an initial photocurrent of 86%after 30 days of storage in air,indicating drastically increased environmental *** strongly suggests that LF is an effective additive for perovskites utilized in optoelectronic devices with high performance.

关键词： leflunomide additive engineering defect passivation perovskite

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阿哌沙班预防亚临床心房颤动患者卒中或全身栓塞的临床研究

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中国临床药理学杂志 2024年第3期40卷 424-424页

作者： hEALEY j S 戴荣源

亚临床心房颤动因持续时间短,无症状,通常只能通过起搏器或除颤器进行长期持续监测才能发现。加拿大麦克马斯特大学hEALEY团队对亚临床心房颤动患者进行了一项持续6 min至24 h的试验,按双盲、双模拟设计,患者被随机分配接受阿哌沙班,剂... 详细信息

亚临床心房颤动因持续时间短,无症状,通常只能通过起搏器或除颤器进行长期持续监测才能发现。加拿大麦克马斯特大学hEALEY团队对亚临床心房颤动患者进行了一项持续6 min至24 h的试验,按双盲、双模拟设计,患者被随机分配接受阿哌沙班,剂量为5 mg,每日2次(2.5 mg,必要时每日2次)或阿司匹林,剂量为81 mg,每日1次。如果亚临床心房颤动持续超过24 h或出现临床心房颤动,则停止试验药物并开始抗凝治疗。主要疗效结局为卒中或全身性栓塞,在意向治疗人群(所有接受随机化的患者)中进行评估;主要安全性结局为大出血,在接受治疗的人群中进行评估(所有接受随机分组并接受至少一剂指定试验药物的患者,在全因永久停止试验药物后5 d进行随访)。

关键词：持续监测无症状心房颤动麦克马斯特大学阿司匹林随机分配阿哌沙班随机化

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低蛋白血症增加人工关节感染一期翻修的失败率

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临床骨科杂志 2024年第5期 666-666页

作者： TRAVERSO g Nú?EZ j h gEhRKE T 胡孔足

营养不良可能增加人工关节感染一期翻修的失败率。作者分析了一组人工关节感染一期翻修的病例，随访至少4年。发现总淋巴细胞计数、血红蛋白水平、白细胞计数、血糖水平以及营养不良没有显著增加人工关节感染一期翻修的失败率，白蛋白...

营养不良可能增加人工关节感染一期翻修的失败率。作者分析了一组人工关节感染一期翻修的病例，随访至少4年。发现总淋巴细胞计数、血红蛋白水平、白细胞计数、血糖水平以及营养不良没有显著增加人工关节感染一期翻修的失败率，白蛋白和C-反应蛋白水平与失败率显著相关。多因素回归分析显示，低蛋白血症显著增加人工关节感染一期翻修的失败率。因此，人工关节感染一期翻修术前检查白蛋白水平很重要。

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