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Kerr-AdS黑洞的基于独立联络形式拉氏量的守恒量

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四川大学学报（自然科学版） 2024年第1期61卷 149-154页

作者：王耀郭伟杰彭俊金贵州师范大学物理与电子科学学院贵阳550001 贵州师范大学贵州省射电天文数据处理重点实验室贵阳550001

基于爱因斯坦引力理论的独立联络形式,由诺特定理可以导出一个含任意参考背景仿射联络的推广Katz-Bicak-Lynden-Bell(KBL)势,借此得到一个守恒量定义式.本文把该定义式应用于渐近anti-de Sitter(AdS)且转动的Kerr-AdS黑洞时空的质量与... 详细信息

基于爱因斯坦引力理论的独立联络形式,由诺特定理可以导出一个含任意参考背景仿射联络的推广Katz-Bicak-Lynden-Bell(KBL)势,借此得到一个守恒量定义式.本文把该定义式应用于渐近anti-de Sitter(AdS)且转动的Kerr-AdS黑洞时空的质量与角动量的定义,给出了与其他标准方法一致的结果.特别地,本文首次构造了一个比通常KBL超势中的参考背景联络更具一般性的新联络,相关结果表明KBL方法中的参考背景联络不具有唯一性,而对它的基本要求就是保持理论的协变性.

关键词： Kerr-AdS黑洞引力场的守恒荷 KBL方法 Kerr黑洞

Mechanisms of pulmonary endothelial barrier dysfunction in acute lung injury and acute respiratory distress syndrome

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Chinese Medical journal Pulmonary and Critical Care Medicine 2024年第2期2卷 80-87页

作者： Yunchao Su Rudolf Lucas david j.R.Fulton Alexander D.Verin Department of Pharmacology&Toxicology Medical College of GeorgiaAugusta UniversityAugustaGA 30912USA Division of Pulmonary and Critical Care Medicine Department of MedicineMedical College of GeorgiaAugusta UniversityAugustaGA 30912USA Vascular Biology Center Medical College of GeorgiaAugusta UniversityAugustaGA 30912USA Research Service Charlie Norwood Veterans Affairs Medical CenterAugustaGA 30912USA

Endothelial cells(ECs)form a semi-permeable barrier between the interior space of blood vessels and the un-derlying *** endothelial barrier integrity is maintained through coordinated cellular processes involving receptors,signaling molecules,junctional complexes,and protein-regulated cytoskeletal *** acute lung injury(ALI)or its more severe form acute respiratory distress syndrome(ARDS),the loss of endothelial barrier integrity secondary to endothelial dysfunction caused by severe pulmonary inflamma-tion and/or infection leads to pulmonary edema and ***-inflammatory agonists such as histamine,thrombin,bradykinin,interleukin 1𝛽,tumor necrosis factor𝛼,vascular endothelial growth factor,angiopoietin-2,and platelet-activating factor,as well as bacterial toxins and reactive oxygen species,cause dynamic changes in cytoskeletal structure,adherens junction disorganization,and detachment of vascular endothelial cadherin(VE-cadherin)from the actin cytoskeleton,leading to an increase in endothelial *** interactions with leukocytes,platelets,and coagulation enhance the inflammatory ***,inflammatory infil-tration and the associated generation of pro-inflammatory cytokines during infection cause EC death,resulting in further compromise of the structural integrity of lung endothelial *** the use of potent antibiotics and aggressive intensive care support,the mortality of ALI is still high,because the mechanisms of pulmonary EC barrier disruption are not fully *** this review,we summarized recent advances in the studies of endothelial cytoskeletal reorganization,inter-endothelial junctions,endothelial inflammation,EC death,and endothelial repair in ALI and ARDS,intending to shed some light on the potential diagnostic and therapeutic targets in the clinical management of the disease.

关键词： Lung Endothelium Pulmonary edema Acute lung injury Acute respiratory distress syndrome

Spiking neural P systems with neuron division and budding

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Science China(Information Sciences) 2011年第8期54卷 1596-1607页

作者： P■un Gheorghe PREZ-jIMNEZ Mario j. Department of Computer Science and Artificial Intelligence university of Sevilla Avda Reina Mercedes s/n 41012 Sevilla Spain Institute of Mathematics of the Romanian Academy PO Box 1-764 014700 Bucuresti Romania

Spiking neural P systems are a class of distributed and parallel computing models inspired by spiking *** this work,the features of neuron division and neuron budding are introduced into the framework of spiking neural P systems,which are processes inspired by neural stem cell division. With neuron division and neuron budding,a spiking neural P system can generate exponential work space in polynomial time as the case for P systems with active *** this way,spiking neural P systems can efficiently solve computationally hard problems by means of a space-time tradeoff,which is illustrated with an efficient solution to SAT problem.

关键词： natural computing membrane computing spiking neural P system neuron division

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湖北省北斗地基增强系统坐标时间序列分析

测绘地理信息 2024年第1期49卷 109-112页

作者：魏以宽邹崇尧陈钧周星宇修延霞邵蕊湖北省测绘工程院湖北武汉430074 吉奥时空信息技术股份有限公司湖北武汉430223 湖北珞珈实验室湖北武汉430079

解算了湖北省北斗地基增强系统的北斗坐标时间序列,并对坐标时间序列性能进行了分析,最后给出北斗和GPS坐标时间序列对比分析方法及案例,从而为省级连续运行基准站快速更新维护提供一种参考方案。

关键词： GNSS 北斗 GPS 时间序列分析大地基准维护

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周年生物钟:赋予动物预知季节的能力

Science Bulletin 2024年第12期69卷 1839-1843页

作者：陈君凤吴蔚龙娟刘鑫 david Hazlerigg 詹祥江 Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China Arctic Seasonal Timekeeping Initiative(ASTI) Department of Arctic and Marine Biology UiTThe Arctic University of NorwayTromsø9037Norway Cardiff university-Institute of Zoology joint Laboratory for Biocomplexity Research Chinese Academy of SciencesBeijing 100101China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming 650223China

Seasonal changes in climate and animal behaviors have been depicted in Chinese literature since ancient times,such as the classical poem"HuìChóng Ch-un jiang Wǎn jǐng"by Su *** now know that the intricate interpla... 详细信息

关键词： periodic behaviors 生物钟

Effects of carbonization temperatures on microstructure of carbon fiber precursors prepared from liquefied wood

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Forestry Studies in China 2009年第4期11卷 238-242页

作者： MA Xiao-j un ZHAO Guang-jie College of Packaging ＆ Printing Engineering Tianjin University of Science ＆ Technology Tianjin 300222 E R. China College of Materials Science and Technology Beijing Forestry University Beijing 100083 P. R. China

In order to enlarge the utilization field of wood and decrease the costs of carbon fibers, carbon fiber precursors from liquefied wood were prepared by soaking liquefied wood in a solution containing hydrochloric acid and formaldehyde, after melt-spinning by adding hexamethylenetetramine. The microstructure evolution of the precursor during carbonization was studied by FTIR, X-ray analysis and Raman spectroscopy. The results show that precursors from liquefied wood above 400℃had diffraction peaks corresponding to the （100） crystal plane. When the carbonization temperature reached 500℃, Raman spectroscopy showed the D peak at wave number of 1360 cm^-1 and the G peak at 1595 cm^-1. By increasing the carbonization temperature, the microstructure of the precursors became more ordered. Although the structure of the precursor changed at 500 and 800℃, the peaks at 1632 and 1454 cm^-1 corresponding to the characteristic vibrations of aromatic rings, remained during carbonization. This implies that the precursor from liquefied wood cannot be easily formed into graphite.

关键词： carbon fiber liquefied wood microstructure temperature

Constrained re-calibration of two-equation Reynolds-averaged Navier–Stokes models

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 82-89页

作者： Yuanwei Bin Xiaohan Hu jiaqi Li Samuel j.Grauer Xiang I.A.Yang Department of Mechanical Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China College of Engineering Peking UniversityBeijing 100871China

Machine-learned augmentations to turbulence models can be advantageous for flows within the training dataset but can often cause harm *** lack of generalizability arises because the constants(as well as the functions)in a Reynolds-averaged Navier–Stokes(RANS)model are coupled,and un-constrained re-calibration of these constants(and functions)can disrupt the calibrations of the baseline model,the preservation of which is critical to the model's *** safeguard the behaviors of the baseline model beyond the training dataset,machine learning must be constrained such that basic calibrations like the law of the wall are kept *** letter aims to identify such constraints in two-equation RANS models so that future machine learning work can be performed without violating these *** demonstrate that the identified constraints are not ***,they help preserve the generalizability of the baseline model.

关键词： Machine learning Turbulence modeling Reynolds-averaged Navier-Stokes

Morphotaxonomy and seasonal distribution of planktonic and benthic Prorocentrales in Karachi waters,Pakistan Northern Arabian Sea

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Chinese journal of Oceanology and Limnology 2013年第2期31卷 267-281页

作者： Sonia MunIR Zaib-un-nisa BURHAN Tahira NAZ P.j.A.SIDDIQUI Steve L.MORTON Centre of Excellence in Marine Biology University of Karachi-75270Pakistan National Oceanic and Atmospheric Administrations 219 Fort Johnson RoadCharleston SC29412USA

Morphotaxonomy and seasonal abundance of dinoflagellates of the genera Prorocentrum and Mesoporos （Prorocentrales） were studied from nutrient-rich waters, Karachi Harbor and the mouth of the Manora Channel, Pakistan during May 2002-july 2003. Using both light and scanning electron microscopy, 13 species of Prorocentrales were identified according to cell shape, size, ornamentation of thecal plates, and architecture of apical platelets, apical pore area, marginal pores, and intercalary bands. P. sigmoides, P. arcuatum, P. scutellum, P. donghaiense, P. balticum, P. minimum, P. emarginatum, P. lima, P. faustiae, and Mesoporos perforatus constitute new records for sindh coast of Pakistan. The most abundant species were P. minimum/P, balticum （4.5x103 cells/L）, P. micans （1.1~103 cells/L）, P. gracile/P, sigmoides （2.5 x 102 cells/L） and P. donghaiense （6.6 x 103 cells/L） at temperatures of 29-31 ~C and salinities of 35-40. Maximum abundance was observed in winter and lower abundance in summer. There was no significant change in the distribution of species between stations except for the benthic species which occurred close to Karachi Harbor waters. Significant positive correlations were observed between Prorocentrum spp. and temperature （R2=0.27） and negative correlations with salinity （R2=-0.32） except for P. minimum and P. emarginatum which has negative correlation with temperature （R2=-0.24） and positive with salinity （R2=0.08, 0.19）. The finding of potential okadaic-acid producing species of benthic Prorocentrum call for monitoring for possible human health problems in this region.

关键词： ecology morphology planktonic/benthic Prorocentrales harmful algae scanning electronaaicroscopy northern Arabian Sea

Simulating FAS-induced apoptosis by using P systems

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Progress in Natural Science:Materials International 2007年第4期17卷 424-431页

作者： Smitha Cheruku Andrei Pǎun Francisco j. Romero-Campero Mario j. Pérez-jiménez Oscar H. Ibarra Department of Computer Science/IfM Louisiana Tech UniversityP.O. Box 10348RustonLA 71272USA Department of Computer Science and Artificial Intelligence University of SevilleAvda. Reina Mercedes s/n 41012SevillaSpain Department of Computer Science University of California-Santa BarbaraSanta BarbaraCA 93106USA

In contrast to differential equations, P systems are an unconventional model of computation which takes into consideration the discrete character of the quantity of components and the inherent randomness that exists in biological phenomena. The key feature of P systems is their compartmentalised structure which represents the heterogeneity of the structural organisation of the cells, and where one can take into account the role played by membranes in the functioning of the system, for example signalling at the cell surface, selective uptake of substances from the media, diffusion across different compartments, etc. We show here that P systems can be a reliable tool for Systems Biology and could even outperform in some cases the current simulation techniques based on differential equations. We will also use a strategy based on the well known Gillespie algorithm but running on more than one compartment called Multi-compartmental Gillespie Algorithm.

关键词： FAS-induced apoptosis P systems deterministic waiting times algorithm multi-compartmental Gillespie algorithm.