Attenuation of Edwardsiella tarda Virulence by Small Peptides That Interfere with LuxS/Autoinducer Type 2 Quorum Sensing

Edwardsiella tarda is a gram-negative pathogen with a broad host range that includes humans, animals, and fish. Recent studies have shown that the LuxS/autoinducer type 2 (AI-2) quorum sensing system is involved in the virulence of E. tarda. In the present study, it was found that the E. tarda LuxS mutants bearing deletions of the catalytic site (C site) and the tyrosine kinase phosphorylation site, respectively, are functionally inactive and that these dysfunctional mutants can interfere with the activity of the wild-type LuxS. Two small peptides, 5411 and 5906, which share sequence identities with the C site of LuxS, were identified. 5411 and 5906 proved to be inhibitors of AI-2 activity and could vitiate the infectivity of the pathogenic E. tarda strain TX1. The inhibitory effect of 5411 and 5906 on AI-2 activity is exerted on LuxS, with which these peptides specifically interact. The expression of 5411 and 5906 in TX1 has multiple effects (altering biofilm production and the expression of certain virulence-associated genes), which are similar to those caused by interruption of luxS expression. Further study found that it is very likely that 5411 and 5906 can be released from the strains expressing them and, should TX1 be in the vicinity, captured by TX1. Based on this observation, a constitutive 5411 producer (Pseudomonas sp. strain FP3/pT5411) was constructed in the form of a fish commensal isolate that expresses 5411 from a plasmid source. The presence of FP3/pT5411 in fish attenuates the virulence of TX1. Finally, it was demonstrated that fish expressing 5411 directly from tissues exhibit enhanced resistance against TX1 infection.

加权模糊相对熵在电机转子故障模糊识别中的应用

提出了一种基于加权模糊相对熵的电机转子故障模糊识别方法。该方法将加权思想引入到模糊相对熵,用于识别电机转子故障严重程度。加权方法的引入增加了信息量丰富的符号区间的模糊相对熵占全部区间模糊相对熵的比重,可以更充分、合理地利用该区间的故障信息进行故障识别。电机转子断条故障诊断仿真实验结果表明,提出的方法有效地实现了电机故障的定量分析,能够准确地识别出电机转子故障的严重程度,使算法的鲁棒性得到了改善,故障分类的可靠性及准确程度得到了提高。

轮-腿-履带复合移动机器人的研究

中国科学院沈阳自动化研究所自行研制的灵豹复合移动机器人,采用轮-腿-履带复合移动机构,构建了嵌入式控制系统,设计了模糊控制器控制机器人行走,实现了机械臂的自主联动控制。机器人运动控制更加简便,系统具备良好的适应性和运动稳定性。

基于状态构形矢量和状态构形矩阵的可重构模块星球机器人构形水

可重构模块星球机器人系统由母体和多个子机器人模块组成,单个模块可以独立运动和操作,多个模块可以重构组合成不同构形,模块采用非对称式轮手一体机构,具有姿态方位性和运动方向性,重构目的是组成在某种环境下更好地完成有向性运动的构形。基于此,提出矢量构形概念,将运动趋势方向和方位性融合到构形拓扑结构中。在模块矢量分析模型基础上,提出并构建状态构形矢量(State configuration vector,SCV)和状态构形矩阵(State configuration matrix,SCM),对非对称式单模块和整体构形的状态信息进行描述,同时支持预定义的数学变换操作,可以表达并触发模块的基础动作、构形重构。提出离散模块组合重构成目标构形的优化分析算法,通过实例仿真计算获得优化分析的选择结果。

避免误操作的遥协作模糊控制方法

现有的遥操作系统中普遍存在的问题是受环境、心理、生理等影响,操作者在遥操作机器人过程中可能由于误操作产生不可预料的后果.为了解决操作者误操作问题,提出对基于操作者通过选择操作手法得到的模糊操作量和对基于多传感器融合决策产生的模糊控制量采取加权和的遥协作模糊控制方法.以遥操作机械手臂为例,通过单纯由操作者、单纯由多传感器融合决策和遥协作模糊控制3种方法进行实验,验证所提出方法的合理性.

主从式UUV群的随从UUV导航

单只水下机器人导航方法存在着各自的缺陷,无法满足低成本UUV群的作业需要。建立由一只具有高精度自主导航能力的主UUV和多只由低成本导航传感器的随从UUV组成的一主多从式UUV群,研究随从UUV导航方法。与前人的极坐标化方法不同,在直角坐标系下对随从UUV导航系统进行了能观性证明。随从UUV通过测距传感器测量自身到主UUV的距离,采用EKF算法进行位置估计,给出了机动航行方案。仿真实验证明了有效性。

基于分层控制的移动机器人最优运动规划

研究移动机器人在带有多移动障碍物的动态环境中的运动规划问题．基于分层最优控制理论，提出了一种新的运动规划方法来解决移动机器人的导航与避障问题．仿真实例证明了该方法的有效性。

北天山新生代构造演化与古环境演变

The Tianshan Mountains is located about 1000-2000 km north of the India-Asia suture and is the most outstanding topography in central Asia, with transmeridional length of nearly 2500 km, north-southern wideness of ~ 300-500 km, peaks exceeding 7000 m above sea level (asl.), and average altitude of over 4000 m asl. Much of the modern relief of the Tianshan Range is a result of contraction driven by the collision of the India subcontinent with the southern margin of Asia, which began in early Tertiary and continues today. Understanding where, when and how the deformation of the Tianshan Mountains occurred is essential to decipher the mechanism of intracontinental tectonics, the process of foreland basin evolution and mountain building, and the history of climate change in central Asia. In order to better constrain the Cenozoic building history of the Tianshan Mountains and the climate change in the southern margin of the Junggar Basin, we carried out multiple studies of magnetostratigraphy, sedimentology, and stable isotopes of paleosol carbonate at the Jingou River section, which is located at the Huoerguosi anticline, the westernest one of the second folds and thrust faults zone in the northern piedmont of the Tianshan Mountains. The Jingou River section with a thickness of about 4160 m is continuous in deposits according to the observed gradual change in sedimentary environments and can be divided into five formations: Anjihaihe, Shawan, Taxihe, Dushanzi and Xiyu in upward sequence. Characteristic remamences were isolated by progressive thermal demagnetization, generally between 300 and 680℃. A total of 1133 out of 1607 samples yielded well-defined ChRMs and were used to establish the magnetostratigraphic column of a 3270-m-thick section from the exposed base of the Anjihaihe Formation to the middle of the Xiyu Formation. Two vertebrate fossil sites and a good correlation with the CK95 geomagnetic polarity time scale suggest that the section was deposited from ~30.5 to ~4.6 Ma and the age of the top of the Xiyu formation is ~2.6 Ma based on an extrapolation of the sedimentation rates. A plot of magnetostratigraphic age vs. height at the Jingou River section shows that significant increases in sedimentation rates as well as notable changes in depositional environments occurred at ~26-22.5 Ma, ~13-11 Ma and ~7 Ma, which represent the initial uplift of the Tianshan Mountains and two subsequent rapid uplift events. In addition, changes in sedimentation rates display characteristic alternations between increases and decreases, which probably indicate that the uplift of the Tianshan Mountains was episodic. We discussed the history of C4 biomass and climatic conditions in the southern margin of the Junggur Basin using the stable carbon and oxygen isotope composition of paleosol carbonates from the Jingou River section during ~17.5-6.5 Ma. The δ13C values indicate that the proportion of C4 biomass was uniform and moderate (15-20 %) during the interval of ~17.5-6.5 Ma. We proposed three hypotheses for this pattern of C4 biomass: (1) counteraction of two opposed factors (global cooling since ~15 Ma and thereafter increased dry and seasonality in central Asia) controlling the growth of C4 grasses, (2) variability in abundance of C3 grasses relative to C3 trees and shrubs if vegetation had ever changed in ecosystems, and (3) the higher latitude of the studied region. The δ18O values show a stepwise negative trend since ~13 Ma which may be attributed to three factors: (1) the temperature decreasing gradually after the middle Miocene (~15 Ma), (2) the increasing contribution of the moistures carried by the polar air masses from the Arctic Ocean to precipitation, and (3) the gradual retreat westward and disappearance of the Paratethys Ocean. Among them, which one played a more important role will need further study of the paleoclimate in central Asia.

油气运聚动力学的模拟分析——以准噶尔盆地为例

The petroleum migration, happening in the geologic past, is the very important and complex dynamic processes in the petroleum systems. It plays a linking role among all static factors in a system. The accumulation is in fact the result of the petroleum migration. For the petroleum geology, the dynamics research of the petroleum migration refers to the mechanism and process research, as well as the use of the quantitative methods. In this thesis, combining with the qualitative analysis and quantitative modeling, the author manages to discuss theoretically some key problems dealing with migration processes, which have not been solved yet, and to apply the studied results in petroleum system analysis in actual basins. The basin analysis offers the base of the numerical modeling for geological phenomena occurring in sedimentary basins, that consists of the sedimentary facies analysis, the section reconstructing technique, eroded thickness estimating, etc. The methods to construct the geologic model, which is needed in the research of oil and gas migration and accumulation, are discussed. The basin analysis offers also the possibility for the latter modeling works to get and select the parameters, such as stratum's thickness, age, stratigraphy etc. Modeling works were done by using two basin modeling softwares: Basin_Mod and TPC_Mod. The role of compaction during the secondary migration and the heterogeneity of migrating paths within the clastic carrier are modeled. And the conclusions were applied in the migration studies in the Jungaer Basin, lying on the Northwest part of the China. To construct a reliable migration model, the author studied the characteristics of the sedimentation, the pore fluid pressure evolution, as well as the distribution and the evolution of fluid potential, following the tectonic evolution of the Jungaer Basin. The geochemical prospecting results were used to evidence and to calibrate the migration processes: the oil-source correlation, the distribution of the properties of oil, gas and water. Finally, two important petroleum systems, Permian one and Jurassic one were studied and identified, according, principally, to the studies on the petroleum migration within the Jungaer Basin. Since the oil, as well as the gas, moves mainly in separate phase during the secondary migration, their migrating behaviors would be determined by the dynamics conditions of migration, including the driving forces and pathways. Based on such a consideration, the further understandings may be acquired: the roles played by permeable carriers and low-permeable source rock would be very different in compaction, overpressure generation, petroleum migration, and so on. With the numerical method, the effect of the compaction on the secondary migration was analyzed and the results show that the pressure gradient and the flux resulted from compaction are so small that could be neglected by comparing to the buoyancy of oil. The main secondary migration driving forces are therefore buoyancy and capillary within a hydrostatic system. Modeling with the commercial software-Basin_Mod, the migration pathways of petroleum in clastic carriers seem to be inhomogeneous, controlled by heterogeneity of the driving force, which in turn resulted from the topography of seals, the fabrics and the capillary pressure of the clastic carriers. Furthermore, the direct and indirect methods to study fault-sealing properties in the course of migration were systemically summarized. They may be characterized directly by lithological juxtaposition, clay smear and diagenesis, and indirectly the comparing the pressures and fluid properties in the walls at two apartments of a fault. In Jungaer Basin, the abnormal pressures are found in the formations beneath Badaowan or Baijantan Formation. The occurrence of the overpressure seems controlled by the stratigraphy. The rapid sedimentation, tectonic pressuring, clay sealing, chemical diagensis were considered as the principal pressuring mechanisms. The evolution of fluid pressure is influenced differently at different parts of the basin by the tectonic stresses. So the basin appears different pressure evolution cycles from each part to another during the geological history. By coupling the results of thermal evolution, pressure evolution and organic matter maturation, the area and the period of primary migration were acquired and used to determine the secondary migration time and range. The primary migration in Fengcheng Formation happened from latter Triassic to early Jurassic in the main depressions. The main period of lower-Wuerhe Formation was at latter Jurassic in Changji, Shawan and Pen-1-jing-xi Depression, and at the end of early Cretaceous in Mahu Depression. The primary migration in Badaowan and Sangonghe Formation is at the end of early-Cretaceous in Changji Depression. After then, the fluid potential of oil is calculated at the key time determined from area and time of the primary migration. Generally, fluid potential of oil is high in the depressions and low at the uplifts. Synthetically, it is recognized that the petroleum migration in the Jungaer Basin is very complex, that leads us to classify the evolution of petroleum systems in Northwestern China as a primary stage and a reformed one. The remigration of accumulated petroleum, caused by the reformation of the basin, results in the generation of multiple petroleum systems. The faults and unconformities are usually the linkers among the original petroleum systems. The Permian petroleum system in Jungaer Basin is such a multiple petroleum system. However, the Jurassic petroleum system stays still in its primary stage, thought the strong influences of the new tectonic activities.

均质弹性条件下多洞平面问题解析算法及其应用研究

The scholars in the world have been trying to find an effective analytic algorithm of multiple hole problems usually meet in engineering designs. Though some studies on circular or elliptic holes had been achieved under specific conditions, no efforts were made to any multiple hole problems that is most significant for engineering designs. The author has made further studies on any multiple hole problems, using complex variable function method and Schwarz alternating method. After solving a series of technological difficulties, the author obtains an effective analytic algorithm, and acquires stress field and displacement field with high accuracy, which can be conducted for arbitrary many iterations according to practical accuracy requirements. In addition, th solution of stress and displacement fields, even for multiple holes of complex shapes and smaller distances. Further, the author made preliminary studies on viscoelastic displacement solution for any double holes. In terms of the obtained displacement solution of any multiple holes, this paper studies displacement back-analysis for the excavations of two tunnels, and find that the back-analysis method is accurate. Additionally, the author presents the mathematical prove of inversion uniqueness for ground stresses, elastic modulus and Poisson ratio. The author believes that the accurate analytic algorithm provided in this paper will presents an effective way to stress and displacement analysis for any multiple hole problems, optimal arrangement of multiple holes, hole shape optimization of multiple holes, etc..

心理咨询师的心理需要及相关因素的研究

The aim of this research is to explore the tendency of needs and its influential factors in counselors at present time．Three studies were carried out: study 1 was to find out the tendency of needs and the structure of needs in counselors. Study 2 was to compare the needs between counselors and non-counselors, in which 64 subjects were students majored in psychology but they don’t want to counsel.Study 3 was to initially explore the relationships between the tendency of needs and its influential factors. Studies of the 1 and 3 selected 123 counselors. It was found that: 1. The results of EPPS in counselors: according to comparison between original marks, the number of subjects who range first from high to low was: introspection，change，dominance，nurse，order，succor，affinity=autonomy，achievement，endurance，heterosexuality，deference，aggression=exhibition=abasement ; according to means of original marks, the tendency of needs from high to low was: introspection，achievement，nurse，autonomy，change，succor，endurance，dominance，order，affinity，aggression，exhibition，deference，abasement，heterosexuality. The lower one of the counselors were needs of aggression, exhibition，deference，abasement and heterosexuality，the high one are introspection，nurse and change．The most difference was achievement need. 2. Dilemmas had no significantly different effect on the needs of counselors, but sexuality and age affect them in some factors. There were significant differences in the factors of deference, exhibition and nurse among different ages. Counselors married had higher tendency of obedience, autonomy, introspection, nurse and endurance than those unmarried. 3. The results of EPPS in non-counselors: according to comparison between original marks, the number of subjects who range first from high to low was: endurance，order，change=dominance，autonomy= introspection=nurse，affinity，succor，aggression，achievement，heterosexuality，exhibition=abasement，deference; according to original marks’means, the tendency of needs from high to low was: nurse，endurance，achievement，order，introspection，change，autonomy，dominance，affinity，succor，aggression，exhibition，abasement，deference，heterosexuality. The lower one of the counselors were needs of aggression, exhibition，deference，abasement and heterosexuality，the high one were introspection，nurse and change．The most difference was achievement need. 4. There were significant differences in the needs of abasement and introspection between counselors and non-counselors. Male counselors and non-counselors had significant differences in the factor of abasement. Female counselors had higher tendency of succor needs. 5. The differences of childhood traumas and positive life events were not significant. The positive and negative life events themselves had no significant differences, but negative life events had marginal significant difference between the two groups. 6. The marks of counselors were lower than non-counselors in the factors of neuroticism. 7. Counselors and trainees had no significant differences among other needs、childhood traumas、life events、personality and coping styles except in the deference need. 8. The result of multiple estimation of EPQ , CTQ and EPPS were related．Many specific life events were related with the tendency of many needs. As shown in the research, children’s traumas, characteristic and life events may affect needs chiefly. 9. There were close relation between characteristic and childhood traumas in counselors. Especially the subjects with more childhood traumas had higher tendency of psychoticism, neuroticism and introvision. There were few persons with much high scores on the Childhood traumas in the subjects．Their personality characteristics indicate high extrovision and low psychoticism．Their childhood traumas may affect the shape of sound personality． Conclusion: 1. The most important tendency of needs were introspection，nurse and change． 2. The differences of childhood traumas and life events were not significant between counselors and non-counselors. The marks of counselors were higher than non-counselors in the factors of introspection, but lower in the factor of neuroticism． 3. The main influential factors in counselors of needs were childhood traumas、characteristic and life events.

Calculation of Blocking Probabilities in Multistage Interconnection Networks with Redundant Paths

The blocking probability of a network is a common measure of its performance. There exist means of quickly calculating the blocking probabilities of Banyan networks; however, because Banyan networks have no redundant paths, they are not inherently fault-tolerant, and so their use in large-scale multiprocessors is problematic. Unfortunately, the addition of multiple paths between message sources and sinks in a network complicates the calculation of blocking probabilities. A methodology for exact calculation of blocking probabilities for small networks with redundant paths is presented here, with some discussion of its potential use in approximating blocking probabilities for large networks with redundant paths.

Recovering Intrinsic Images from a Single Image

We present an algorithm that uses multiple cues to recover shading and reflectance intrinsic images from a single image. Using both color information and a classifier trained to recognize gray-scale patterns, each image derivative is classified as being caused by shading or a change in the surface's reflectance. Generalized Belief Propagation is then used to propagate information from areas where the correct classification is clear to areas where it is ambiguous. We also show results on real images.

Pre-empting Plateau: the nature of topological transitions in foam

Hutzler, S., Weaire, D., Cox, S.J., Van der Net, A. and Janiaud, E. (2007) Pre-empting Plateau: the nature of topological transitions in foam. Europhys. Lett. 77: 28002 Sponsorship: EPSRC / ESA / ESTEC / Science Foundation Ireland/ Gulbenkian Foundation

Quasi -symmetric designs with good blocks and intersection number one

Mavron, Vassili; McDonough, T.P.; Schrikhande, M.S., (2003) 'Quasi -symmetric designs with good blocks and intersection number one', Designs Codes and Cryptography 28(2) pp.147-162 RAE2008