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Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn Laura Bennet Hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

Precipitation analysis of as-cast HK40 steel after isothermal aging

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International journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1125-1133页

作者： M.L. Saucedo-Munoz A. Ortiz-Mariscal V.M. Lopez-Hirata j.d. Villegas-Cardenas Orlando Soriano-Vargas Erika O. Avila-davila Instituto Politecnico Nacional (ESIQIE) Apdo. Postal 118-395 Mexico D.F. 07300 Universidad Politecnica Metepec y Tultitlan Edo. Mex. Mexico Tecnológico de Estudios Superiores de jocotitlan Jocotitlan Edo. Mex. Mexico

As-cast HK40 steel was aged at 700, 800, or 900℃ for times as long as 2000 h. Microstructural characterization showed that the primary M_7C_3 carbide network contained a substantial content of manganese, in agreement with the microsegregation of manganese calculated by Thermo-Calc using the Scheil–Gulliver module. The dissolution of primary carbides caused the solute supersaturation of austenite and subsequent precipitation of fine M_(23)C_6 carbides in the austenite matrix for aged specimens. during prolonged aging, the carbide size increased with increasing time because of the coarsening process. A time–temperature–precipitation diagram for M_(23)C_6 carbides was calculated using the Thermo-CalcPRISMA software; this diagram showed good agreement with the experimental growth kinetics of precipitation. The fine carbide precipitation caused an increase in hardness; however, the coarsening process of carbides promoted a decrease in hardness. Nanoindentation tests of the austenite matrix indicated an increase in ductility with increasing aging time.

关键词： as-cast HK40 steel carbide precipitation aging precipitation simulation

INFLUENCE OF TIN ON THE HOT dUCTILITY OF A LOW-CARBON STEEL

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 478-482页

作者： Z.X.Yuan j.jia A.M.guo d.d.Shen S.H.Song j.Liu SchoolofMaterialsandMetallurgy WuhanUniversityofScienceandTechnologyWuhan430081China ResearchInstituteofWuhanIron＆SteelCompany Wuhan430080China

The influence of tin on the hot ductility of a 0.15wt%C steel is investigated using a continuous-casting thermal simulator with three cooling rates. Tin can apparently deteriorate the hot ductility of the steel. Non-equilibrium grain boundary segregation of tin occurs during cooling and plays an important role in reducing the hot ductility of the steel. There is a critical cooling rate for the Sn segregation being between 5 and 20K/s.

关键词： hot ductility non-equilibrium segregation steel grain boundary impurity

Vegetation productivity responses to drought on tribal lands in the four corners region of the Southwest USA

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Frontiers of Earth Science 2018年第1期12卷 37-51页

作者： Mohamed Abd Salam EL-VILALY Kamel dIdAN Stuart E. MARSH Willem j.d. VAN LEEUWEN Michael A. CRIMMINS Armando Barreto MUNOZ The Intemational Food Policy Research Institute Washington DC 20006-1002 USA Vegetation Index and Phenology Lab Department of Agricultural and Biosystems Engineering The University of Arizona Tucson AZ 85721-0036 USA Arizona Remote Sensing Center School of Natural Resources and the Environment The University of Arizona Tucson AZ 85721-0043 USA department of Soils Water and Environmental Science The University of Arizona Tucson AZ 85721-0038 USA

For more than a decade, the Four Comers Region has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources while exacerbating soil erosion. These persistent droughts threaten ecosystem services, agriculture, and livestock activities, and expose the hypersensitivity of this region to inter-annual climate variability and change. Much of the intermountain Western United States has sparse climate and vegetation monitoring stations, making fine-scale drought assessments difficult. Remote sensing data offers the opportunity to assess the impacts of the recent droughts on vegetation productivity across these areas. Here, we propose a drought assessment approach that integrates climate and topographical data with remote sensing vegetation index time series. Multisensor Normalized difference Vegetation Index （NdVI） time series data from 1989 to 2010 at 5.6 km were analyzed to characterize the vegetation productivity changes and responses to the ongoing drought. A multi-linear regression was applied to metrics of vegetation productivity derived from the NdVI time series to detect vegetation productivity, an ecosystem service proxy, and changes. The results show that around 60.13% of the study area is observing a general decline of greenness （p 〈 0.05）, while 3.87% show an unexpected green up, with the remaining areas showing no consistent change. Vegetation in the area show a significant positive correlation with elevation and precipitation gradients. These results, while, confirming the region＇s vegetation decline due to drought, shed further light on the future directions and challenges to the region＇s already stressed ecosystems. Whereas the results provide additional insights into this isolated and vulnerable region, the drought assessment approach used in this study may be adapted for application in other regions where surfacebased climate and vegetation monitoring record is spatially and temporally limited.

关键词： drought remote sensing Hopi Navajo Nation

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秦岭山脉南北麓暴雨触发条件对比分析

高原气象 2025年第1期44卷 178-190页

作者：武麦凤乔舒婷郭大梅任小同渭南市气象局陕西渭南714000 陕西省气象台陕西西安710014

采用实况气象观测资料、FY-2G卫星云图资料、多普勒雷达资料和ERA50.25°×0.25°逐小时再分析资料,对2021年8月21-22日同时发生在秦岭南北麓的强等级暴雨过程进行对比分析,探讨秦岭南北麓暴雨触发条件的影响机制。结果表明:秦岭北麓流... 详细信息

采用实况气象观测资料、FY-2G卫星云图资料、多普勒雷达资料和ERA50.25°×0.25°逐小时再分析资料,对2021年8月21-22日同时发生在秦岭南北麓的强等级暴雨过程进行对比分析,探讨秦岭南北麓暴雨触发条件的影响机制。结果表明:秦岭北麓流场上,西风带系统在秦岭特殊地形作用下,对流层低层形成中尺度气旋性环流,通过热力作用触发暴雨,对流性降水持续时间短,强度小;湿斜压性增强是秦岭北麓暴雨开始的一个信号,当湿斜压性减弱以及中层比湿减小时,降水结束。对秦岭南麓而言,地形作用下对流层低层流场形成中尺度辐合线触发暴雨;降水释放的凝结潜热加热低层大气,与中低层入侵的冷空气共同构建对流不稳定结构,上升运动增强,降水增强和持续;对流云团在高温高湿的环境下迅速组织化合并发展,形成中尺度对流复合体(MCC),对流强度大,对流层结深厚,小时雨强大;中低层冷空气的入侵和扩散到地面的时间分别与秦岭南麓强降水的开始和结束时间对应。

关键词：秦岭地形暴雨动力作用热力作用

Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole

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上海交通大学学报 2004年第z2期38卷 79-82页

作者： j.L.Song d.j.Hu Q.C.Wang H.Q.Chen H.G.guo School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.

关键词： alternator claw-pole casting-forging near net forming numerical simulation

STUdY ON THE SHOCK WAVE CRYSTALLIZATION OF AMORPHOUS ALLOYS BY dSC

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Acta Metallurgica Sinica(English Letters) 2002年第5期15卷 431-438页

作者： H. Y. Zhao, H. Wang, Q.j. Liu, j.d. Kan and Z.Q. Liudepartment of Materials Science and Engineering, Yunnan University, Kunming 650091, China department of Materials Science and Engineering Yunnan University

Shock wave and annealing crystallization of amorphous alloys FeSiB, FeMoSiB and FeCuNbSiB were studied by isothermal and non-isothermal dSC technique. It was found that the shock wave crystallization is very perfect, the fraction crystallized is very close to 100%, though the period of crystallization is very short, only about 10-4-10-6s. Their produced phases differ from the parent phase in structure and composition. The high velocity of the transformation is very difficult to explain by the diffusion theory of solid state phase transition.

关键词： amorphous alloy nano-crystallization shock wave crystalliza-tion

Identifying damage caused by the 2008 Wenchuan earthquake from VHR remote sensing data

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International journal of digital Earth 2009年第4期2卷 309-326页

作者： d.Ehrlicha H.d.guo K.Molch j.W.Ma M.Pesaresi European Commission-joint Research Centre Via E.Fermi 2749Ispra21027 Italy Center for Earth Observation and digital Earth-Chinese Academy of Sciences Beijing100190 China

The paper discusses the potential of very high resolution(VHR)satellite imagery for post-earthquake damage assessment in comparison with the role of aerial ***-disaster optical and radar satellite data are assessed for their ability to resolve collapsed buildings,destroyed transportation infrastructure,and specific land cover *** VHR imagery has shown to be effective in quantifying building stock and for assessing damage at the building *** synthetic aperture radar(SAR)imagery requires further research to identify optimum information extraction procedures for rapid assessment of affected *** on current technical and operational capabilities increasing efforts should be devoted to the generation of spatial datasets for disaster preparedness.

关键词： damage assessment earthquake Sichuan settlements VHR SAR

Speeding up transmissions of unknown quantum information along Ising-type quantum channels

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Chinese Physics B 2017年第1期26卷 125-130页

作者： W j guo L F Wei Quantum Optoelectronics Laboratory Southwest Jiaotong University Chengdu 610031 China State Key Laboratory of Optoelectronic Materials and Technologies School of Physics Sun Yat-Sen University Guangzhou 510275 China

Quantum teleportation with entanglement channels and a series of two-qubit SWAP gates between the nearestneighbor qubits are usually utilized to achieve the transfers of unknown quantum state from the sender to the distant receiver. In this paper, by simplifying the usual SWAP gates we propose an approach to speed up the transmissions of unknown quantum information, specifically including the single-qubit unknown state and two-qubit unknown entangled ones,by a series of entangling and disentangling operations between the remote qubits with distant interactions. The generic proposal is demonstrated specifically with experimentally-existing Ising-type quantum channels without transverse interaction; liquid NMR-molecules driven by global radio frequency electromagnetic pulses and capacitively-coupled josephson circuits driven by local microwave pulses. The proposal should be particularly useful to set up the connections between the distant qubits in a chip of quantum computing.

关键词： unknown quantum information transfers Ising-type quantum chains NMR molecules superconducting circuits