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Phase-Field Models for Biofilms II.2-D Numerical Simulations of Biofilm-Flow Interaction

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Communications in Computational Physics 2008年第6期4卷 72-101页

作者： Tianyu Zhang nick Cogan Qi Wang Department of Mathematics Florida State UniversityTallahasseeFL 32306-4510USA. School of Mathematics Nankai UniversityTianjin 300071China

We study the biofilm-flow interaction resulting in biofilm growth,deformation and detachment phenomena in a cavity and shear flow using the phase field model developed recently[28].The growth of the biofilm and the biofilm-flow interaction in various flow and geometries are simulated using an extended Newtonian constitutive model for the biofilm mixture in *** model predicts growth patterns consistent with experimental findings with randomly distributed initial biofilm *** induced deformation,and detachment in biofilms is simulated in a shear ***,streaming,and ultimate detachment phenomena in biofilms are demonstrated in the simulations,respectively,in a shear *** merging of detached biofilm blobs in oscillatory shear is observed in simulations as *** due to the density variation is also investigated shedding light on the possible bacteria induced detachment.

关键词： Biofilm Cahn-Hilliard equation phase filed finite difference method multiphase flow.

Fit for purpose: Modeling wholesale electricity markets realistically with multi-agent deep reinforcement learning

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Energy and AI 2023年第4期14卷 500-513页

作者： nick Harder Ramiz Qussous Anke Weidlich University of Freiburg Department of Sustainable Systems Engineering INATECHEmmy-Noether-Str.2Freiburg im Breisgau79110Germany

Electricity markets need to continuously evolve to address the growing complexity of a predominantly renewable energy-driven,highly interconnected,and sector-integrated energy *** models allow testing market designs before implementation,which offers advantages for market robustness and *** work presents a novel approach to simulate the electricity market by using multi-agent deep reinforcement learning for representing revenue-maximizing market *** learning capability makes the agents highly adaptive,thereby facilitating a rigorous performance evaluation of market mechanisms under challenging yet practical *** distinct test cases that vary the number and size of learning agents in an energy-only market,we demonstrate the ability of the proposed method to diagnose market manipulation and reflect market *** method is highly scalable,as demonstrated by a case study of the German wholesale energy market with 145 learning *** makes the model well-suited for analyzing large and complex electricity *** capability of the presented simulation approach facilitates market design analysis,thereby contributing to the establishment future-proof electricity markets to support the energy transition.

关键词： Agent-based modeling Reinforcement learning Machine learning Electricity markets Multi-agent reinforcement learning

Urological Emergencies at the University Hospital of Brazzaville: Epidemiological, Clinical, and Therapeutic Aspects

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Open Journal of Urology 2024年第5期14卷 333-345页

作者： Roland Bertile Banga-Mouss Yannick Dimi Nyanga Irène Ondima Armel Melvin Atipo Ondongo Steve Aristide Ondziel-Opara Joseph Junior Damba nick Arnaud Monabeka Christ Ondzé Daniella Gloire Ngassiele Gidmard Onguele Henock Songa Jetsvy Mayala Anani Wensels Severin Odzebe Prosper Alain Bouya Departement of Urology and Andrology University Hospital of Brazzaville Brazzaville Republic of the Congo

Introduction: Urological emergencies play a significant role in the medical and surgical activity of a urology department. The objective of this study was to determine the hospital prevalence of urological emergencies at the University Hospital of Brazzaville (CHUB), identify the different pathologies requiring urgent care, and list the various therapeutic methods. Patients and methods: A retrospective study of patients admitted to the medical and surgical emergencies department of CHUB over a 5-year period. Patient records admitted and treated for a urological emergency were included. The variables studied were the frequency of urological emergencies, patient age at admission, gender, nature of the emergency, and various therapeutic options. Results: Urological emergencies accounted for 4.3% of all medical and surgical emergencies. The mean age was 57 ± 28 years with a range of 3 to 93 years. The male-to-female ratio was 7.1. The most common conditions were urinary retention (54.67%), hematuria (17.20%), and renal colic (8.13%). Therapeutically, surgical urinary drainage was dominated by cystostomy. Conclusion: Urological emergencies are infrequent at the University Hospital of Brazzaville. Their management is often delayed.

关键词： Urological Emergencies Urinary Retention Hematuria Renal Colic

Nucleus-Encoded Light-Harvesting Chlorophyll a/b Proteins are Imported Normally into Chlorophyll b-Free Chloroplasts of Arabidopsis

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Molecular Plant 2013年第3期6卷 860-871页

作者： Sabine nick Jorg Meurer Jurgen Soil Elisabeth Ankele Dept Biologie I-Botanik Biozentrum LMU Munchen Grosshadernerstrasse 2-4 D-82152 Planegg-Martinsried Germany Munich Center for Integrated Protein Science ClPSM Ludwig-Maximilians-Universitat Munchen Feodor-Lynen-Strasse 25 D-81377 Munich Germany

Chloroplast-located proteins which are encoded by the nuclear genome have to be imported from the cytosol into the organelle in a posttranslational manner. Among these nuclear-encoded chloroplast proteins are the light- harvesting chlorophyll a/b-binding proteins （LHCPs）. After translation in the cytosol, precursor proteins of LHCPs are imported via the TOC/TIC translocase, processed to their mature size to insert into thylakoid membranes where they recruit chlorophylls a and b to form pigment-protein complexes. The translocation of proteins is a highly regulated process which employs several regulators. To analyze whether CAO （chlorophyll a oxigenase） which converts chlorophyll a to chlorophyll b at the inner chloroplast membrane, is one of these regulators, we performed import reactions utilizing a homozygous loss-of-function mutant （cao-1）. We imported in vitro translated and 35S-labeled precursor proteins of light- harvesting proteins of photosystem II LHCB1, LHCB4, and LHCB5 into chloroplasts isolated from cao-1 and show that import of precursor proteins and their processing to mature forms are not impaired in the mutant. Therefore, regulation of the import machinery cannot be responsible for the decreased steady-state levels of light-harvesting complex （LHC） proteins. Regulation does not take place at the transcriptional level either, because Lhcb mRNAs are not down-regulated. Additionally, reduced steady-state levels of LHCPs also do not occur due to posttranslational turnover of non-functional LHCPs in chloroplasts. Taken together, our data show that plants in the absence of CAO and therefore devoid of chlorophyll b are not influenced in their import behavior of LHC proteins.

关键词： chloroplast import LHCPs cao-1 protein complex assembly thylakoid membranes photosynthesis.

Gallbladder emptying in patients with primary sclerosing cholangitis

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World Journal of Gastroenterology 2009年第28期15卷 3498-3503页

作者： Karouk Said nick Edsborg Nils Albiin Annika Bergquist Department of Gastroenterologyand Hepatology Karolinska Institute Karolinska University Hospital Huddinge14186 Stockholm Sweden Division of Radiology Karolinska Institute Karolinska University Hospital Huddinge 14186 Stockholm Sweden

AIM： To assess gallbladder emptying and its association with cholecystitis and abdominal pain in patients with primary sclerosing cholangitis （PSC）. METHODS： Twenty patients with PSC and ten healthy subjects were investigated. Gallbladder fasting volume, ejection fraction and residual volume after ingestion of a test meal were compared in patients with PSC and healthy controls using magnetic resonance imaging. Symptoms, thickness and contrast enhancement of the gallbladder wall and the presence of cystic duct strictures were also assessed. RESULTS： Median fasting gallbladder volume in patients with PSC [67 （19-348） mL] was twice that in healthy controls [32 （16-55） mL] （P 〈 0.05）. The median postprandial gallbladder volume in patients with PSC was significantly larger than that in healthy controls （P 〈 0.05）. There was no difference in ejection fraction, gallbladder emptying volume or mean thickness of the gallbladder wall between PSC patients and controls. Contrast enhancement of the gallbladder wall in PSC patients was higher than that in controls; （69% ± 32%） and （42% ± 21%）（P 〈 0.05）. No significant association was found between the gallbladder volumes and occurrence of abdominal pain in patients and ***： Patients with PSC have increased fasting gallbladder volume. Gallbladder Mucosal dysfunction secondary to chronic cholecystitis, may be a possible mechanism for increased gallbladder.

关键词： Cholecystitis Ejection fraction Gallbladdervolume Magnetic resonance imaging

How will climate change affect the potential distribution of Eurasian tree sparrows Passer montanus in North America？

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Current Zoology 2011年第5期57卷 648-654页

作者： Jim GRAHAM Catherine JARNEVICH nick YOUNG Greg NEWMAN Thomas STOHLGREN Natural Resource Ecology Laboratory Colorado State University Fort Collins CO 80523-1499 USA Fort Collins Science Center U.S. Geological Survey 2150 Centre Ave. Building C Fort Collins CO 80526 USA

Habitat suitability models have been used to predict the present and future potential distribution of a variety of spe- cies. Eurasian tree sparrows Passer montanus, native to Eurasia, have established populations in other parts of the world. In North America, their current distribution is limited to a relatively small region around its original introduction to St. Louis, Missouri. We combined data from the Global Biodiversity Information Facility with current and future climate data to create habitat suitability models using Maxent for this species. Under projected climate change scenarios, our models show that the distribution and range of the Eurasian tree sparrow could increase as far as the Pacific Northwest and Newfoundland. This is potentially important in-formation for prioritizing the management and control of this non-native species [Current Zoology 57 （5）： 648--654, 2011].

关键词： Eurasian tree sparrows Passer montanus Maxent Climate change Distribution model

Zircon U-Pb-Hf constraints from Gongga Shan granites on young crustal melting in eastern Tibet

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Geoscience Frontiers 2019年第3期10卷 885-894页

作者： nick M.W.Roberts Michael P.Searle NERC Isotope Geosciences Laboratory British Geological Survey Environment Science Centre Department of Earth Sciences University of Oxford

The Gongga Shan batholith is a complex granitoid batholith on the eastern margin of the Tibetan Plateau with a long history of magmatism spanning from the Triassic to the Pliocene. Late Miocene-Pliocene units are the youngest exposed crustal melts within the entire Asian plate of the Tibetan ***, we present in-situ zircon Hf isotope constraints on their magmatic source, to aid the understanding of how these young melts were formed and how they were exhumed to the surface. Hf isotope signatures of Eocene to Pliocene zircon rims(ε_(Hf)(t)=-4 to +4), interpreted to have grown during localised crustal melting, are indicative of melting of a Neoproterozoic source region, equivalent to the nearby exposed Kangding Complex. Therefore, we suggest that Neoproterozoic crust underlies this region of the Songpan-Ganze terrane, and sourced the intrusive granites that form the Gongga Shan batholith. Localised young melting of Neoproterozoic lower or middle crust requires localised melt-fertile lithologies. We suggest that such melts may be equivalent to seismic and magnetotelluric low-velocity and high-conductivity zones or "bright spots" imaged across much of the Tibetan Plateau. The lack of widespread exposed melts this age is due either to the lack of melt-fertile rocks in the middle crust, the very low erosion level of the Tibetan plateau, or to a lack of mechanism for exhuming such melts. For Gongga Shan, where some melting is younger than nearby thermochronological ages of low temperature cooling, the exact process and timing of exhumation remains enigmatic, but their location away from the Xianshuihe fault precludes the fault acting as a conduit for the young melts. We suggest that underthrusting of dry granulites of the lower Indian crust(Archaean shield) this far northeast is a plausible mechanism to explain the uplift and exhumation of the eastern Tibetan Plateau.

关键词： Tibet Himalaya Hf isotopes Zircon Crustal melting

The Warming of the Tibetan Plateau in Response to Transient and Stabilized 2.0℃/1.5℃Global Warming Targets

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Advances in Atmospheric Sciences 2022年第7期39卷 1198-1206,I0014-I0017页

作者： Jintao ZHANG Qinglong YOU Fangying WU Ziyi CAI nick PEPIN Institute of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China Innovation Center of Ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 518057China CMA-FDU Joint Laboratory of Marine Meteorology Shanghai 200438China School of Environment Geographyand GeosciencesUniversity of PortsmouthPortsmouth PO13HEU.K

As "the third pole", the Tibetan Plateau(TP) is sensitive to climate forcing and has experienced rapid warming in recent decades. This study analyzes annual and seasonal near-surface air temperature changes on the TP in response to transient and stabilized 2.0℃/1.5℃ global warming targets based on simulations of the Community Earth System Model(CESM). Elevation-dependent warming(EDW) with faster warming at higher elevations is predicted. A surface energy budget analysis is adopted to uncover the mechanisms responsible for the temperature changes. Our results indicate a clear amplified warming on the TP with positive EDW in 2.0℃/1.5℃ warmer futures, especially in the cold season. Mean TP warming relative to the reference period(1961–90) is dominated by an enhanced downward longwave radiation flux, while the variations in surface albedo shape the detailed pattern of EDW. For the same global warming level, the temperature changes under transient scenarios are ~0.2℃ higher than those under stabilized scenarios, and the characteristics of EDW are broadly similar for both scenarios. These differences can be primarily attributed to the combined effects of differential downward longwave radiation, cloud radiative forcing, and surface sensible and latent heat fluxes. These findings contribute to a more detailed understanding of regional climate on the TP in response to the long-term climate goals of the Paris Agreement and highlight the differences between transient and stabilized warming scenarios.

关键词： elevation-dependent warming(EDW) Paris Agreement Tibetan Plateau transient and stabilized warming temperature

History and the Han Fei Zi

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History and the Han Fei Zi

作者： nick Mithen 复旦大学

学位级别：硕士

中国传统文化往往与一尘不变的,循环的,没有活力的历史观念紧密地联系在一起。通常与欧洲的现代化那种充满活力的,直接的,以进步为目标的历史发展形式背道而驰。在过去的50年问,这种文明模式被大范围的观点所批评,导致它逐渐地,但非绝对... 详细信息

中国传统文化往往与一尘不变的,循环的,没有活力的历史观念紧密地联系在一起。通常与欧洲的现代化那种充满活力的,直接的,以进步为目标的历史发展形式背道而驰。在过去的50年问,这种文明模式被大范围的观点所批评,导致它逐渐地,但非绝对的,在严谨学术讨论中失去信誉。更何况在学术界和普通大众间,巨大的文明的观点继续默默地对着中国历史和哲学进行解读。根据这些讨论的内容来看,这份论文的意图旨在发掘战国时代哲学家韩非子,作为一个在历史和政治思想中举足轻重的人物,作为一个普遍的方式。这篇论文旨在解读韩非子的哲学,脱离中国哲学与历史的传统叙事方式。前者围绕着哲学流派,流畅的动向,和圣洁般的思想家,互相跨世纪的对话的关系网,后者会通过政治,自上而下的与大人物和事件驱动目的论来阐明。通过以一个王朝的叙述来剖析自己,文章的重点会始终保持历史性。鉴于韩非子及他的哲学对话者和他们提出的很大程度被铭记的他的社会历史性的社会环境方面,而不是冗长的,超然的或者如政治游戏中的筹码。从这角度讲,这份论文,尤其是它的后半部,将会通过呈现一段智慧的历史来最大化的,追求成为一部哲学作品或哲学历史作品。这种对中国哲学的解读部分源于对历史哲学独立性的确信。也来自在学术界内更理性更严格地哲学性的方法的普遍目的2。同时,这个现代的研究持占着的不是对于此类研究的评击,而是对于它们的赞赏。它提供了一个可选择的观点和智慧的框架。结合进一步了解一个公共项目理解的操作方法的纯粹性为主旨,最后一章将考虑如何比较国际视野,在平行的思想家,知识分子和世界其他地区的荟萃历史进程的描绘,以及赋予这份研究伟大的意义是。本质上,旨在重新契合上述疑难问题的解释和史学问题,在具体的哲学和历史学术建设中,假设一个建立在中国人和全球文化延申的非传统观念。以下初步意见后的目标将提供一些基本的方向。第一部分旨在提供什么样的主题和问题,本文将探讨一个知识分子的态度和定向。二是务实地设计,旨在全面预览叙事结构和理论框架,这也是本文将采用的。工作在串联,这两部分将建设一个有用的平台,从事与本论文的主要论点。所有的社会和个人的都有历史意义的;他们存在于现在,同是也存在于历史的长河里。不是所有的个人和社会,然而,他们以同样的历史方式体验和设想这是第一次确定了欧洲思想家在18世纪和19世纪的世纪假定。感知历史时间的文化轨迹,黑格尔,马克思和海格尔等知识分子,构思历史性的文明模式。这是由欧洲文明的基本史实,离不开其哲学上升到自我意识和建立在进步和发展的历史变化的模型的线性最终确定。并列地针对这种张扬的西方是旧世界的剩下的残缺又里程碑似的非历史,首先是亚洲的,挣扎的前现代的静态周期性。这种现代化模式成为很好根深蒂固,在正反两方面的表现,在学术和大众话语;它雕刻西方人怎么看自己,他们如何看向东转向亚洲,以及如何构思亚洲人自己的文明。在后者的第二十届和新生的二十一世纪上半叶很多学术研究的目的是解构这种单片文明本质主义的,强调西方和非西方历史叙述中的活力和多元化3。这种批评的渗透却受到了限制,往往成为研究和自身领域,而不是作为经营机制转换和改革等学科4。在某种程度上,这种文明的角度来看的普及程度是由于其概念二分法的价值-的连续性导向与对历史和历史变迁发生变化或应变为导向的观点5。在一个显著意义上的挑战是从它的文明锚地分离这一概念的二分法：使用它作为一种人类学的工具,用来检讨历史的发展,而不是禁锢理论的笼子。中国作为亚洲文明的核心之一,先后承担这种文化具体化的冲击,而且在某些情况下,接受它,使用它作为从一个平台来证明,同时用它来防范快速的现代化6。.静态的,周期性的,保守的,和非西方全历史意识的指派已经与中国的儒家传统和理想化的道德思想和过去的模式,和目前的评估密切相关7。以这种重要的途径,这种非历史的历史紧密结合,以人与自然的在中国文化的感知团结,再次并列反对他们在欧洲的刻板8。这些方向已经由西方人和中国人,充满了丰富的修辞关于中国与过去的亲密关系中,特别是’中国’形式的历史意识,从而构成本身禁忌西方现代哲学说明两者9。虽然中国哲学的一些传统方面起到了加强中国的印像：作为非历史-一个建立社会政治组织里的元历史理想的宇宙连续性,道德和宇宙-最近学者呼吁中国的知识遗产,以呈现一个完全多而杂画面。这些修订还有,较大地,出现了融合,虽然也许不是直接对话,与欧洲和西方中心主义,它挑战了关于解释的文明模式假设的多维批判,鼓励更多的学术反思,并要求一个更具历史代表性的方法,文化,哲学和历史10。尽管存在这些挑战,文明的耻辱仍然是决定奖学金含蓄的影响力,对于中国和亚洲的流行观点。它是在不断的反思后,这些文明的分类,及其有效性或缺乏,那本文将从事与分析它的对象-历史上的韩非子的概念-而其最终目标是要回到这些主题中的结论。以下部分将系统地绘制出如何将这个项目

关键词：韩非子政治思想社会变迁历史哲学战国时期