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通过实验表征、计算机辅助结构解析和原子模拟对切尔西土壤腐植酸进行三维结构模拟

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腐植酸 2022年第5期 60-75页

作者： Mamadou S.Diallo Andre Simpson Paul Gassman Jean Loup Faulon james h.johnson William A.Goddard Patrick G.hatcher 袁飞巩冠群(译) 加州理工学院贝克曼研究所139-74材料和工艺模拟中心加利福尼亚州帕萨迪纳91125 霍华德大学土木工程系华盛顿特区20059 多伦多大学斯卡伯勒学院物理科学系加拿大多伦多MIC 1A4 太平洋西北国家实验室环境分子科学实验室华盛顿州里奇兰99352 桑迪亚国家实验室计算生物学和进化计算部加利福尼亚州利弗莫尔94551-0969 俄亥俄州立大学化学系俄亥俄州哥伦布43210 中国矿业大学化工学院徐州221116

本文描述了一个用于开发腐植酸(hAs)三维结构模型的完整的实验和计算框架。这种方法结合了实验表征、计算机辅助结构解析(CASE)和原子模拟,生成与hAs的分析数据和热力学/结构特性相一致的所有三维结构模型或这些模型的代表性样本。从元... 详细信息

本文描述了一个用于开发腐植酸(hAs)三维结构模型的完整的实验和计算框架。这种方法结合了实验表征、计算机辅助结构解析(CASE)和原子模拟,生成与hAs的分析数据和热力学/结构特性相一致的所有三维结构模型或这些模型的代表性样本。从元素分析、漫反射傅里叶变换红外光谱、一维/二维~1h和C溶液核磁共振光谱和电喷雾电离四极杆飞行时间质谱(ESI QqTOF MS)中获得的结构数据,结合CASE程序SIGNATURE,生成了切尔西土壤腐植酸(hA)所有的三维结构模型。这些模型随后被用作初始三维结构,进行恒温恒压分子动力学模拟,以估算其体密度和hildebrand溶解度参数。只有少数模型异构体显示出的分子组成和体热力学性质与实验数据一致。这些模型异构体的等摩尔混合物的模拟C核磁共振光谱与切尔西土壤hA的实测光谱相比有较好的一致性。

关键词：土壤多肽和蛋白质分子模拟碳水化合物核磁共振光谱

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina hromada Patrick heimel Markus Kerbl LászlóGál Sylvia Nürnberger Barbara Schaedl james Ferguson Nicole Swiadek Xavier Monforte Johannes C.heinzel Antal Nógrádi Andreas h.Teuschl-Woller David hercher Department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). however, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Emergency Logistics Management for hazardous Materials with Demand Uncertainty and Link Unavailability

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Journal of Systems Science and Systems Engineering 2023年第2期32卷 175-205页

作者： Ginger Y.Ke james h.Bookbinder Faculty of Business Administration Memorial University of NewfoundlandSt.John’sNewfoundland and LabradorA1B 3X5Canada Department of Management Sciences University of WaterlooWaterlooOntarioN2L 3G1Canada

Due to its harmful nature,any incident associated with hazardous material(hazmat)may cause tremendous impacts on the surrounding people and the *** on the incident involving this specific type of good,we develop a reliable and robust emergency logistics network that considers both demand uncertainty and possible unavailability of particular links.A time-based risk measure is carefully designed upon the traditional risk assessment to reflect the stakeholder’s sensitivity to risk over response *** disruption and uncertainty are modeled as two sets of scenarios which are integrated into a bi-objective robust model to evaluate the trade-offs between risk and *** effectiveness of the emergency response can be assured by expenditures that add extra capacities to certain links or establish additional facilities that aid recovery from *** apply our model and approach to a real-world network in Guangdong *** results reveal the necessity of embedding consideration of uncertainty and unreliability into emergency network design problems;outline the importance of hedging against unpredictability by system redundancies;and indicate the impact of stakeholder’s orientation towards cost and risk on the location,allocation,and routing decisions in hazmat emergency response.

关键词： Emergency response hazardous materials robust optimization link disruption emergency demand uncertainty

Imagery Enhancement and Interpretation for Remote Visual Inspection of Aging Civil Infrastructure

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Tsinghua Science and Technology 2008年第S1期13卷 375-380页

作者： Lucio Soibelman james h Garrett Department of Civil and Environmental Engineering Carnegie Mellon University

In this paper, we describe an image enhancement and interpretation methodology to enhance and recognize surface defects and critical patterns from remote imagery of sewer pipeline inspection. The objective is to provide inspectors and professionals with better tools to allow them to examine the imagery for condition assessment. We present initial results of a collaboration with a robotic company through a case study on computer-assisted processing and interpretation of sewer pipeline inspection imagery. In the mean time, the described enhancement and interpretation methodology can also be applied to sewer pipeline condition assessment in an offline mode, where this methodology can support professionals’ examination of acquired sewer condition imagery.

关键词： remote visual inspection infrastructure assessment image processing and analysis defects region of interest detection classification

Roles of Financial Innovation and Information Technology:Lessons from US Sub-prime Mortgage Crisis and Its Implications for China

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Chinese Geographical Science 2012年第3期22卷 343-355页

作者： james h LENZER JR Simon Xiaobin ZhAO International Center for China Development Studies & Department of Geography Faculty of Social Sciencesthe University of Hong KongHong KongChina

The mortgage loan has evolved from a local lending instrument into a major global security and its role is unparallel to other financial instruments in the process of financial globalization. This paper explains how technology and financial innovation transformed the mortgage loan from a local security into a premier global security traded worldwide. It examines the fundamental flaws of this process and why it does not work in regards to mortgage lending and the re-securitization products that were created through financial innovation. The findings show that regulation was unable to keep pace with financial innovation, which created an environment where actors in the financial service sector were able to behave geographically irresponsibly by using information asymmetries to their advantage by par- ticipating in moral hazard activities and engaging in other immoral and unethical business practices that were centered around localized geography, which ultimately contributed to the global financial crisis. It also examines the roll of financial innovation in regard to the Lehman Brothers Mini-Bond in hung and its role as a driving force behind China＇s newly emerging shadow banking sector. It concludes with a policy recommendation and its implication for China＇s continued economic development.

关键词： shadow banking US sub-prime mortgage crisis financial tsunami global financial crisis wealth man- agement vehicle China asset bubble

high nymphal host density and mortality negatively impact parasitoid complex during an insect herbivore outbreak

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Insect Science 2019年第2期26卷 351-365页

作者： Aidan A. G. hall Scott N. johnson james M. Cook Markus Riegler hawkesbury Institute for the Environment Western Sydney University NSW Australia

Insect herbivore outbreaks frequently occur and this may be due to factors that restrict top-down control by parasitoids, for example, host-parasitoid asynchrony, hyperparasitization, resource limitation and climate. Few studies have examined hostparasitoid density relationships during an in sect herbivore outbreak in a n atural ecosystem with diverse parasitoids. We studied parasitization patterns of Cardiaspina psyllids during an outbreak in a Eucalyptus woodland. First, we established the trophic roles of the parasitoids through a species-specific multiplex PCR approach on mummies from which parasitoids emerged. Then, we assessed host-parasitoid density relationships across three spatial scales (leaf, tree and site) over one yeas We detected four endoparasitoid species of the family Encyrtidae (hymenoptera);two primary parasitoid and one heteronomous hyperparasitoid Psyllaephagus species (the latter with female development as a primary parasitoid and male development as a hyperparasitoid), and the hyperparasitoid Coccidoctonuspsyllae. Parasitoid development was host-synchronized, although synchrony between sites appeared constrained during winter (due to temperature differences). Parasitization was predominantly driven by one primary parasitoid species and was mostly inversely host-density dependent across the spatial scales. hyperparasitization by C. psyllae was psyllid-density dependent at the site scale, however, this only impacted the rarer primary parasitoid. high larval parasitoid mortality due to density-dependent nymphal psyllid mortality (a consequence of resource limitation) compounded by a summer heat wave was incorporated in the assessment and resulted in density independence of host-parasitoid relationships. As such, high larval parasitoid mortality during insect herbivore outbreaks may contribute to the absence of host density-dependent parasitization during outbreak events.

关键词： density-dependent mortality insect outbreak psyllid synchronization temperature trophic interactions

Kartogenin induces cartilage-like tissue formation in tendon–bone junction

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Bone Research 2014年第1期2卷 61-70页

作者： Jianying Zhang james h-C Wang MechanoBiology Laboratory Departments of Orthopaedic Surgery Bioengineering Mechanical Engineering and Materials Science and Physical Medicine and Rehabilitation University of Pittsburgh

Tendon-bone junctions （TBJs） are frequently injured, especially in athletic settings. healing of TBJ injuries is slow and is often repaired with scar tissue formation that compromises normal function. This study explored the feasibility of using kartogenin （KGN）, a biocompound, to enhance the healing of injured TBJs. We first determined the effects of KGN on the proliferation and chondrogenic differentiation of rabbit bone marrow stromal cells （BMSCs） and patellar tendon stern/progenitor cells （PTSCs） in vitro. KGN enhanced cell proliferation in both cell types in a concentration-dependent manner and induced chondrogenic differentiation of stem cells, as demonstrated by high expression levels of chondrogenic markers aggrecan, collagen II and Sox-9. Besides, KGN induced the formation of cartilage-like tissues in cell cultures, as observed through the staining of abundant proteoglycans, collagen II and osteocalcin. When injected into intact rat patellar tendons in vivo, KGN induced cartilage-like tissue formation in the injected area. Similarly, when KGN was injected into experimentally injured rat Achilles TBJs, wound healing in the TBJs was enhanced, as evidenced by the formation of extensive cartilage-like tissues. These results suggest that KGN may be used as an effective cell-free clinical therapy to enhance the healing of injured TBJs.

关键词： bone junction BMSCs

Potential hydrodynamic origin of frictional transients in sliding mesothelial tissues

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Friction 2013年第2期1卷 163-177页

作者： Stephen h.LORING james P.BUTLER Department of Anesthesia Critical Care and Pain MedicineBeth Israel Deaconess Medical Center and Harvard Medical SchoolBoston MA 02215USA Department of Medicine Division of Sleep MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBoston MA 02215USA

Steady-state and transient variations in frictional force observed in tribological experiments of mesothelial tissues sliding in lubricant were analyzed with a mathematical model to test the hypothesis that such phenomena are manifestations of elastohydrodynamic lubrication and,importantly,do not require physical contact between the sliding *** model incorporates three phenomena characteristic of elastohydrodynamic lubrication:thinning of the liquid layer between sliding surfaces under a normal load(“squeeze-out”),thickening of the liquid layer due to hydrodynamic pumping,and smoothing of the elastic surfaces caused by hydrodynamic pressure *** in soft mesothelial tissues sliding in lubricant showed variations in steady state friction with velocity,load,and lubricant *** non-steady sliding,the decay rate of frictional transients at the start of rotation varied with velocity,the amplitudes of these transients varied with the preceding periods without rotation,and frictional force varied during sinusoidal *** simulations were qualitatively similar to experimental results,supporting these *** lubricant viscosity increased lubricating layer thickness and lowered friction at low speeds and increased friction at high speeds,supporting hydrodynamic *** conclude that the frictional variations seen with sliding mesothelial tissues are consistent with elastohydrodynamic lubrication without contact between the sliding surfaces.

关键词： pleural space breathing pericardium lubrication model

Boldness and predator evasion in naturally hybridizing swordtails （Teleostei： Xiphophorus）

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Current Zoology 2015年第4期61卷 596-603页

作者： james B. johnson Zachary W. CULUMBER Ryan EASTERLING Gil G. R.OSENThAL Department of Biology Texas A&M University College Station Texas TX 77843 USA Centro de lnvestigaciones Cientificas de las huastecas "Aguazarca" Calnali Hidalgo Mexico

Correlations among behavioral traits can generate trade-offs and constrain phenotypic evolution. Interspecific hybridization has the potential to alter behavioral trait correlations, but the effect of hybridization on suites of behavioral traits has received relatively little attention. We evaluated how natural hybridization changes the relationship between boldness （time of emergence and proportion of time out of shelter） and response to a simulated predator threat in swordtails （Teleostei： Xiphophorus）. In poeciliid fishes, bold individuals have increased survival in the presence of predators. This non-intuitive observation may arise as a result of bold individuals being more likely to engage in anti-predator behaviors. Contrary to our prediction, bold indi- viduals were less likely to perform a fast-start response to a predator threat. This correlation was consistent among populations and species but was only significant in hybrids. The observed correlation between boldness and anti-predator behavior could im- pact hybrid fitness and the evolvability of hybrid lineages. More generally, our findings suggest that hybridization could influence the integration of behavioral phenotypes, as has been amply documented for morphology. Animal personality and behavioral syndromes could therefore play an important role in the evolutionary fate of natural hybrids [Current Zoology 61 （4）： 596-603, 2015].

关键词： Trait compensation Fast-Start Anti-predator behavior hybridization Behavioral syndrome Animal personality