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Cerebral ischemia and neuroregeneration

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Neural Regeneration Research 2018年第3期13卷 373-385页

作者： Reggie H.C.Lee Michelle H.H.Lee Celeste Y.C.Wu Alexandre Couto e Silva Harlee E.Possoit Tsung-Han Hsieh Alireza Minagar Hung Wen Lin Department of Neurology Louisiana State University Health Science Center Center for Brain Health Louisiana State University Health Science Center Institute of Cellular and System Medicine National Health Research Institutes Department of Cellular Biology and Anatomy Louisiana State University Health Science Center Cardiovascular and Metabolomics Research Center Hualien Tzu Chi Hospital

Cerebral ischemia is one of the leading causes of morbidity and mortality worldwide. Although stroke （a form of cerebral ischemia）-related costs are expected to reach 240.67 billion dollars by 2030, options for treatment against cerebral ischemia/stroke are limited. All therapies except anti-thrombolytics （i.e., tissue plasminogen activator） and hypothermia have failed to reduce neuronal injury, neurological deficits, and mortality rates following cerebral ischemia, which suggests that development of novel therapies again st stroke/cerebral ischemia are urgently needed. Here, we discuss the possible mechanism（s） underlying cerebral ischemia-induced brain injury, as well as current and future novel therapies （i.e., growth factors, nicotinamide adenine dinucleotide, melatonin, resveratrol, protein kinase C isozymes, pifithrin, hypothermia, fatty acids, sympathoplegic drugs, and stem cells） as it relates to cerebral ischemia.

关键词： cerebral ischemia melatonin resveratrol protein kinase C pifithrin-α fatty acids sympathetic nervous system neuromodulation therapy traditional Chinese therapies stem cel

Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin

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Journal of Geographical sciences 2025年第1期 88-111页

作者： YANG Peng SUN Kaiya ZHU Yanchao XIA Jun HUANG Heqing SONG Jingxia SHI Xiaorui LU Xixi Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information Engineering China University of Geosciences Department of Geography National University of Singapore state Key Laboratory of Water Resources and Hydropower Engineering science Wuhan University

Wetlands play a critical role in the global environment. The Middle Yangtze River Basin(MYRB), known for its abundant wetland resources, has experienced notable changes resulting from the complex interplay of environmental factors. Therefore, we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to *** the random forest(RF) regression algorithm and patch-generated land-use simulation(PLUS) model, we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP) framework from 2035 to 2095. The main findings are as follows:(1) The RF algorithm was optimal for land-use and land-cover(LULC) classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings. However, the forested area exhibited an increase and decrease of 3.9% and 1.2% under the SSP1-2.6 and SSP5-8.5 scenarios, respectively, whereas farmland exhibited a diminishing trend.(2) Wetlands were primarily concentrated in the central and eastern MYRB, with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020. Notably,wetland coverage revealed significantly high level, significant changes, frequent but relatively minor changes under the SSP1-2.6, SSP2-4.5, and SSP 5-8.5 scenarios, respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities, indicating a clear degradation in habitat quality across different scenarios. In conclusion, we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds.

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Geochemical systematics of the Mauranipur-Babina greenstone belt,Bundelkhand Craton,Central India:Insights on Neoarchean mantle plume-arc accretion and crustal evolution

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Geoscience Frontiers 2018年第3期9卷 769-788页

作者： S.P.Singh K.S.V.Subramanyam C.Manikyamba M.Santosh M.Rajanikanta Singh B.Chandan Kumar Department of Geology Institute of Earth SciencesBundelkhand UniversityJhansiU.P284128India CSIR-National Geophysical Research Institute Uppal RoadHyderabad500007India Department of Earth sciences University of AdelaideAustralia School of Earth science&Resources China University of GeosciencesBeijingChina Department of Geology Central University of KeralaKasaragodKerala671316India

The Neoarchean Bundelkhand greenstone sequences at Mauranipur and Babina areas within the Bundelkhand Gneissic Complex preserve a variety of magmatic rocks such as komatiitic basalts, basalts,felsic volcanic rocks and high-Mg andesites belonging to the Baragaon, Raspahari and Koti *** intrusive and extrusive komatiitic basalts are characterized by low SiO_2(39-53 wt.%), high MgO(18-25 wt.%).moderately high Fe_2O_3(7.1-11.6 wt.%), Al_2O_3(4.5-12.0 wt.%), and TiO_2(0.4-1.23 wt.%)with super to subchondritic(Gd/Yb)N ratios indicating garnet control on the melts. The intrusive komatiitic suite of Ti-enriched and Al-depleted type possesses predominant negative Eu and positive Nb, Ti and Y anomalies. The chemical composition of basalts classifies them into three types with varying SiO_2, TiO_2, MgO, Fe_2O_3, Al_2O_3 and CaO. At similar SiO_2 content of type Ⅰ and Ⅲ basalts, the type II basalts show slightly high Al_2O_3 and Fe_2O_3 contents. Significant negative anomalies of Nb, Zr, Hf and Ti, slightly enriched LREE with relatively flat HREE and low ∑REE contents are observed in type Ⅰ and Ⅱ basalts. TypeⅢ basalts show high Zr/Nb ratios(9.8-10.4), TiO_2(1.97-2.04 wt.%), but possess strikingly flat Zr, Hf, Y and Yb and are uncontaminated. Andesites from Agar and Koti have high SiO_2(55-64 wt.%), moderate TiO_2(0.4-0.7 wt.%), slightly low Al_2O_3(7-11.9 wt.%), medium to high MgO(3-8 wt.%) and CaO contents(10-17 wt.%). Anomalously high Cr, Co and Ni contents are observed in the Koti rhyolites. Tholeiitic to calc alkaline affinity of mafic-felsic volcanic rocks and basalt-andesite dacite-rhyolite differentiation indicate a mature arc and thickened crust during the advanced stage of the evolution of Neoarchean Bundelkhand greenstone belt in a convergent tectonic setting where the melts were derived from partial melting of thick basaltic crust metamorphosed to amphibolite-eclogite facies. The trace element systematics suggest the presence of arc-back arc association w

关键词： Bundelkhand craton Greenstone belts Mantle dynamics Plume-arc accretion Neoarchean crustal evolution

Increased humic materials explain aggregate-protected carbon and nitrogen accumulation in biochar-amended tropical soils

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Pedosphere 2024年第6期34卷 1086-1099页

作者： Emmanuel AMOAKWAH Mohammad A.RAHMAN Khandakar R.ISLAM Kwame A.FRIMPONG Christian A.PHARES Louis SACKEY Isaac ASIRIFI Emmanuel ARTHUR council for Scientific and Industrial Research-Soil Research Institute Accra Center Soil Water and Bioenergy Resources The Ohio State University South Centers Department of Soil science College of Agriculture and Natural Sciences School of Agriculture University of Cape Coast Ruhr-Universit?t Bochum Geographic Institute Department of Soil Science and Soil Ecology Department of Agroecology Faculty of Technical Sciences Arhus University

Humic materials make important contributions to soil organic carbon（C） and nitrogen（N） ***,information on the correlation between humic substances and the accumulation of soil aggregate-protected C and N in response to biochar application under tropical agroecosystems is ***,a field trial was conducted to elucidate the effects of biochar on soil aggregate properties and humic materials and how these humic compounds affect aggregate-protected C and N in a humid tropical *** treatments included no-biochar control（CK）,15 Mg biochar ha-1（BC-15）,30Mg biochar ha-1（BC-30）,and 30 Mg biochar ha-1+phosphate fertilizer（BC-30+P）.The treatments BC-30 and BC-30+P significantly increased the contents of humic materials（humic and fulvic acids） as compared to *** was a significant increase in the mean-weight diameter of soil aggregates by3-and 4-fold in BC-30 and BC-30+P,***,BC-30 and BC-30+P led to significant increases in soil structural coefficient by 3-and 4-fold,re spectively,relative to *** increases in organic C and N accumulation were observed in the macroaggregates of the biochar-amended *** relationships between the degree of polymerization and aggregate-protected C and N were observed,implying that low-molecular-weight aliphatic compounds favor organic C and N accumulation with biochar *** important soil property that contributed to organic C and N accumulation in aggregates was fulvic acid content,which could be used as an early and sensitive indicator to notice early changes in aggregate-protected C and N accumulation in soils of the humid tropics.

关键词： degree of humification fulvic acid humic acid macroaggregates soil structural coefficients

A CADe system for nodule detection in thoracic CT images based on artificial neural network

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science China(Information sciences) 2017年第7期60卷 177-194页

作者： Xinglong LIU Fei HOU Hong QIN Aimin HAO state Key Laboratory of Virtual Reality Technology and Systems Beihang University School of Computer science and Engineering Nanyang Technological University Department of Computer science Stony Brook University

Lung cancer has been the leading cause of cancer-related deaths in 2015 in United states. Early detection of lung nodules will undoubtedly increase the five-year survival rate for lung cancer according to prior studies. In this paper, we propose a novel rating method based on geometrical and statistical features to extract initial nodule candidates and an artificial neural network approach to the detection of lung nodules. The novel method is solely based on 3D distribution of neighboring voxels instead of user-specified features. During initial candidates detection, we combine organized region properties calculated from connected component analysis with corresponding voxel value distributions from statistical analysis to reduce false positives while retaining true nodules. Then we devise multiple artificial neural networks(ANNs) trained from massive voxel neighbor sampling of different types of nodules and organize the outputs using a 3D scoring method to identify final nodules. The experiments on 107 CT cases with 252 nodules in LIDC-IDRI data sets have shown that our new method achieves sensitivity of 89.4% while reducing the false positives to 2.0 per case. Our comprehensive experiments have demonstrated our system would be of great assistance for diagnosis of lung nodules in clinical treatments.

关键词： artificial neutral network Lung nodule computed tomography computer aided detection nodule detection

Optimizing Mechanical Properties of AlCoCrFeNiTi_x High-Entropy Alloys by Tailoring Microstructures

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Acta Metallurgica Sinica(English Letters) 2013年第3期26卷 277-284页

作者： Yinfeng WANG Shengguo MA Xiaohua CHEN Juyan SHI Yong ZHANG Junwei QIAO College of Materials science and Engineering Taiyuan University of Technology state Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Key Laboratory of Interface science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology

The effects of Ti additions and the heat treatment on the mechanical properties of AlCoCrFeNiTix （x = 0, 0.2, 0.3, 0.4 and 0.5） high-entropy alloys （HEAs） were studied. The results show that the dendrite phase with a body-centered-cubic （bcc） structure transforms into the interdendrite phase with a new bcc structure. With the increase of the Ti contents and heat-treatment temperature, the average hardness and yield strengths are greatly improved, and the highest hardness and yielding strength are 583 HV and 2.07 GPa, respectively in the investigated HEA system. The as-cast and annealed HEAs exhibit excellent mechanical properties, combining with high yielding strength and plasticity. The solid solution strengthening mechanism of Ti additions is responsible for the strengthening effect of AlCoCrFeNiTix HEAs.

关键词： High-entropy alloy Microstructure Compressive property Hardness Heat treatment

MgCo2-D2 and MgCoNi-D2 systems synthesized at high pressures and interaction mechanism during the HDDR processing

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Progress in Natural science:Materials International 2017年第1期27卷 74-80页

作者： Chubin Wan V.E.Antonov R.V.Denys V.I.Kulakov V.A.Yartys University of science and Technology Beijing Institute for Energy Technology Institute of Solid state Physics Russian Academy of Sciences HYSTORSYS AS Norwegian University of science and Technology

MgCo2and MgNiCo crystallize with hexagonal Laves type intermetallic structures of the C14 type and do not form hydrides at ambient hydrogen pressures. However, applying high hydrogen pressures in the GPa range forces the hydrogen absorption and leads to the formation of multi-phase compositions, which contain approximately 2.5 atoms H per formula unit of MgCo2or MgNiCo and remain thermally stable under normal *** hydrogenation of MgCo2resulted in its decomposition to a ternary Mg2CoD5deuteride and metallic cobalt. Phase-structural transformations accompanying the vacuum desorption of deuterium in the temperature range of 27–500 °C were studied using in situ neutron powder diffraction. The investigation showed a complete recovery of the initial MgCo2intermetallic via a Hydrogenation-Disproportionation-Desorption-Recombination process. At 300°C, the Mg2CoD5deuteride first decomposed to elementary Mg and hexagonal Co. At 400°C, a MgCo phase was formed by interaction between Mg and Co. At the highest processing temperature of 500°C, a solid-state interaction of MgCo and Co resulted in the recovery of the initial *** interaction of MgNiCo with deuterium under the synthesis conditions of 2.8 GPa and 200 °C proceeded in a more complex way. A very stable ternary deuteride MgNi2D3was leached away while Co was separated in the form of Mg2CoD5and the remaining nickel formed a solid solution with Co with the approximate composition *** thermal desorption of deuterium from MgCo2D2.5and from MgNiCoD2.5has been studied by Thermal Desorption Spectroscopy with deuterium released into a closed volume. The observed effects nicely correlate with changes in the phase structural composition of the hydrides ***2is a new example of the hydrogen storage alloy, in which a successful HDDR processing results in the reversible formation of the initial intermetallic at much lower temperatures than in the equilibrium phase diagram of the Mg-Co system.

关键词： Intermetallics Hydrogen storage materials Neutron powder diffraction High pressure synthesis Phase-structural transformations Magnesium Cobalt Nickel

Analyses and calculations of noise in optical coherence tomography systems

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Frontiers of Optoelectronics 2008年第Z2期1卷 247-257页

作者： Xiaonong ZHU Yanmei LIANG Youxin MAO Yaqing JIA Yiheng LIU Guoguang MU Institute of Modern Optics Nankai University Key Laboratory of Opto-electronic Information Science and Technology Ministry of Education Institute for Microstructural science National Research Council Canada

Significant progress has been made in the study of optical coherence tomography(OCT) — a non-invasive, high resolution, and in vivo diagnostic method for medical imaging applications. In this paper, the principles of noise analyses for OCT systems have been *** are made of signal-to-noise ratios for both balanced and unbalanced detection schemes under the ideal no-stray light situation as well as the non-ideal situation where residual reflections and scatterings are presented. Numerical examples of noise calculation accompanied by detailed comparison of the main characteristics of both time-domain and frequency-domain OCT systems are also presented. It is shown that a larger dynamic range can be achieved for a Fourier-domain OCT system even under the circumstances of high-speed image *** main results presented in this paper should be useful for the development of high performance OCT systems.

关键词： optical coherence tomography (OCT) noise analyses sensitivity signal-to-noise ratio (SNR)

Assessment of Soil Water Content in Field with Antecedent Precipitation Index and Groundwater Depth in the Yangtze River Estuary

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Journal of Integrative Agriculture 2013年第4期12卷 711-722页

作者： XIE Wen-ping YANG Jing-song state Key Laboratory of Soil and Sustainable Agriculture/Institute of Soil science Chinese Academy of Sciences

To better understand soil moisture dynamics in the Yangtze River Estuary （YRE） and predict its variation in a simple way, a field monitoring experiment was carried out along the north branch of the Yangtze River, where seawater intrusion was strong and salt-water variation is one of the limiting factors of local agriculture. In present paper, relation between antecedent precipitation index （API） and soil water content is studied, and effects of groundwater depth on soil water content was analyzed. A relatively accurate prediction result of soil water content was reached using a neural network model. The impact analysis result showed that the variation of the API was consistent with soil water content and it displayed significant correlations with soil water content in both 20 and 50 cm soil layer, and higher correlation was observed in the layer of 20 cm. Groundwater impact analysis suggested that soil moisture was affected by the depth of groundwater, and was affected more greatly by groundwater at depth of 50 cm than that at 20 cm layer. By introducing API, groundwater depth and temperature together, a BP artificial network model was established to predict soil water content and an acceptable agreement was achieved. The model can be used for supplementing monitoring data of soil water content and predicting soil water content in shallow groundwater areas, and can provide favorable support for the research of water and salt transport in estuary area.

关键词： antecedent precipitation index groundwater depth soil water content assessment