Ergodic Theory, Interpretations of Probability and the Foundations of Statistical Mechanics

The traditional use of ergodic theory in the foundations of equilibrium statistical mechanics is that it provides a link between thermodynamic observables and microcanonical probabilities. First of all, the ergodic theorem demonstrates the equality of microcanonical phase averages and infinite time averages (albeit for a special class of systems, and up to a measure zero set of exceptions). Secondly, one argues that actual measurements of thermodynamic quantities yield time averaged quantities, since measurements take a long time. The combination of these two points is held to be an explanation why calculating microcanonical phase averages is a successful algorithm for predicting the values of thermodynamic observables. It is also well known that this account is problematic.This survey intends to show that ergodic theory nevertheless may have important roles to play, and it explores three other uses of ergodic theory. Particular attention is paid, firstly, to the relevance of specific interpretations of probability, and secondly, to the way in which the concern with systems in thermal equilibrium is translated into probabilistic language. With respect to the latter point, it is argued that equilibrium should not be represented as a stationary probability distribution as is standardly done; instead, a weaker definition is presented.     

Modeling large reversible electric-field-induced strain in ferroelectric materials using 90° orientation switching

Reversible large electric-field-induced strain caused by reversible orientation switchings in BaTiO3 is modeled using the Landau's theory of phase transition.A triple well free energy function is constructed.Each of its minima is associated with one of the polarization orientations involved.Nonlinear constitutive laws accounting for reversible orientation switchings and electrostriction effects are obtained by using thermodynamic equilibrium conditions.Hysteretic dynamics of onedimensional structures is des...     

Dielectric tunable properties of BaTi_4O_9-doped Ba_(0.6)Sr_(0.4)TiO_3 microwave composite ceramics

BaTi4O9-doped Ba0.6Sr0.4TiO3(BST) composite ceramics were prepared by the conventional solid-state reaction and their structure,dielectric nonlinear characteristics and microwave dielectric properties were investigated.The secondary phase of the orthorhombic structure Ba4Ti13O30 is formed among BST composite ceramics with the increase of BaTi4O9.At the same time,a duplex or bimodal grains size distribution shows fine grains in a coarse grain matrix.The degree of frequency dispersion of dielectric permittivity below Tm is increased initially and then decreased with respect to BaTi4O9.As the BaTi4O9 content increases,the tunability of composite ceramics decreases,while the Q value increases.Interestingly,70 wt%BaTi4O9-doped BST has a tunability～4.0%(under 30 kV/cm biasing) versus a permittivity～68 and quality factor ～134.1(at～3.2 GHz) .     

高速铁路用水泥乳化沥青浆体的物理结构

基于硬化硅酸盐水泥浆体的Powers理论和水泥乳化沥青浆体的配合比,通过理论计算和X射线衍射(XRD)、扫描电子显微镜(SEM)、能量色散X射线谱仪(EDAX)等相分析方法,分析了硬化水泥乳化沥青浆体的物相组成与微结构.结果表明,硬化水泥乳化沥青浆体的物相组成与微结构取决于沥灰比和水灰比.提出了表征硬化水泥乳化沥青浆体物理结构的两种结构模型,以沥青为连续相、水泥相为分散相的有机-无机复合胶凝体结构模型—I型模型;以水泥相为基体、沥青嵌入其中的无机-有机复合胶凝体结构模型—II型模型.为深入分析高速铁路板式无砟轨道结构中水泥乳化沥青砂浆的微结构参数和力学性能及其衰变规律奠定了基础.     

Inorganic polyphosphate induces accelerated tube formation of HUVEC endothelial cells

In this study, the effect of inorganic polyphosphate (polyP) on the initial phase of angiogenesis and vascularization was investigated, applying the HUVEC cell tube formation assay. PolyP is a physiological and high energy phosphate polymer which has been proposed to act as a metabolic fuel in the extracellular space with only a comparably low ATP content. The experiments revealed that polyP accelerates tube formation of human umbilical vein endothelial cells (HUVEC), seeded onto a solidified basement membrane extract matrix which contains polyP-metabolizing alkaline phosphatase (ALP) activity. This effect is abolished by co-addition of apyrase, which degrades ATP to AMP and inorganic phosphate. The assumption that ATP, derived from polyP, activates HUVEC cells leading to tube formation was corroborated by experiments showing that addition of polyP to the cells causes a strong rise of ATP level in the culture medium. Finally, we show that at a later stage of cultivation of HUVEC cells, after 3 d, polyP causes a strong enhancement of the expression of the genes encoding for the two major matrix metalloproteinases (MMPs) released by endothelial cells during tube formation, MMP-9 and MMP-2. This stimulatory effect is again abrogated by addition of apyrase together with polyP. From these results, we propose that polyP is involved either directly or indirectly in energy supply, via ALP-mediated transfer of energy-rich phosphate under ATP formation. This ATP is utilized for the activation and oriented migration of endothelial cells and for the matrix organization during the initial phases of tube formation.     

Adipocyte extracellular matrix composition, dynamics and role in obesity

The central role of the adipose tissue in lipid metabolism places specific demands on the cell structure of adipocytes. The protein composition and dynamics of the extracellular matrix (ECM) is of crucial importance for the functioning of those cells. Adipogenesis is a bi-phasic process in which the ECM develops from a fibrillar to a laminar structure as cells move from the commitment phase to the growth phase characterized by storage of vast amounts of triglycerides. Mature adipocytes appear to spend a lot of energy on the maintenance of the ECM. ECM remodeling is mediated by a balanced complement of constructive and destructive enzymes together with their enhancers and inhibitors. ECM remodeling is an energy costing process regulated by insulin, by the energy metabolism, and by mechanical forces. In the obese, overgrowth of adipocytes may lead to instability of the ECM, possibly mediated by hypoxia.     

生物能量在生命体中传递的新理论及实验证实

我们从蛋白质的分子结构和ATP水解所放出能量的特征出发,提出了一个新的生物能量传递理论。并用新的哈密顿函数和波函数代替了原来旧的函数,用解析的方法求出了传递生物能量的孤子在其生理温度和它的寿命时间内能够传递过上千个氨基酸分子,于是它可能是传递生物能量的真正载流子。用解析和数值模拟的方法研究了这种传递生物能量孤子的特性和在生理温度300K时的热力学稳定性,证明了这种孤子在生理温度时是十分稳定的,它的寿命能达到300ps,可能是生物能量的传递者。再通过实验测定了在胶原蛋白和牛血清蛋白等(-螺旋蛋白的光谱特性及其在27-95℃范围内其谱线分布和谱线强度随温度的变化,把所检测的三个结果与能量传递的理论预示的结果相比较,发现它们完全一致,从而从实验上证明了在蛋白质分子中建立的生物能量传递理论是正确的。而理论预示的孤子是蛋白质当中生物能量传递的真正载流子。     

On the stability of cognitive processes

An empirical and mathematical model for self-organization is proposed, based on elemental properties, on unique interaction and on the combination of hierarchical elements. In the model, higher elements are stabilized by the 'cognitive' (strong) interaction of subelements, disregarding intermediate elements. This is called 'elementary reductionism' and is illustrated by the sequence quarks-elementary particles-atoms-molecules-cells-organisms- societies. Optimal dynamic interaction of nonidentical elements is called 'cognitive stability'. This is compared with thermodynamic equilibrium. The principal differences are outlined.     

64层螺旋CT血管成像对肠系膜上动脉活体形态的显示及临床应用

目的探讨64层螺旋cT血管成像（CTA）对肠系膜上动脉（SMA）活体形态的显示及临床应用价值。方法对80例临床疑有腹部、盆腔疾病的患者行64层螺旋CTA扫描,然后利用容积再现（VR）、多平面重建（MPR）、最大密度投影（MIP）、反向MIP（I—MIP）和薄层MIP（TS．MIP）等技术进行后处理。80例患者分为正常组（30例）和异常组（50例）两组,对正常组采用多种重建技术显示SMA各级分支,并测量SMA的直径,观察SMA起始段的走行;在MPR像上测量SMA与腹主动脉（AA）的夹角（An）,在左肾静脉（LRV）平面测量SMA至AA的距离（M）,在左侧肾门旁测量LRV最大前后径（A）,在SMA与AA问测量LRV最小前后径（B）。对异常组采用多种重建技术显示SMA,分析SMA特点。结果VR、MIP、I-MIP像均可显示正常组SMA整体解剖形态,TS-MIP对小分支显示优于其他重建技术。不同重建方式对SMA直径的测量无显著差异（F=0．71,P〉0．05）。SMA起始段走行方向为右下走行90％,前下走行占6．7％,左下走行占3．3％。An平均为（61．06±22．79）°。M平均为（14．62±4．00）mm,A平均为（9．16±1．91）mm,B平均为（6．00±2．01）mm,A与B比值〉2者占20．0％,〉3者占3．3％。异常组中有5例小肠先天性旋转不良及2例小肠扭转,SMA轴位像主要表现“回旋征”,VR表现为“螺旋征”;1例SMA分支栓塞;消化道肿瘤19例,其中8例供血动脉为SMA分支;回盲部动静脉畸形1例;余22例肝脏、泌尿生殖系统病变SMA无明显异常。结论64层螺旋CTA能很好地显示SMA的活体形态特征,具有重要的临床应用价值。     

Quantum jumps,superpositions, and the continuous evolution of quantum states

The apparent dichotomy between quantum jumps on the one hand, and continuous time evolution according to wave equations on the other hand, provided a challenge to Bohr's proposal of quantum jumps in atoms. Furthermore, Schrödinger's time-dependent equation also seemed to require a modification of the explanation for the origin of line spectra due to the apparent possibility of superpositions of energy eigenstates for different energy levels. Indeed, Schrödinger himself proposed a quantum beat mechanism for the generation of discrete line spectra from superpositions of eigenstates with different energies.However, these issues between old quantum theory and Schrödinger's wave mechanics were correctly resolved only after the development and full implementation of photon quantization. The second quantized scattering matrix formalism reconciles quantum jumps with continuous time evolution through the identification of quantum jumps with transitions between different sectors of Fock space. The continuous evolution of quantum states is then recognized as a sum over continually evolving jump amplitudes between different sectors in Fock space.In today's terminology, this suggests that linear combinations of scattering matrix elements are epistemic sums over ontic states. Insights from the resolution of the dichotomy between quantum jumps and continuous time evolution therefore hold important lessons for modern research both on interpretations of quantum mechanics and on the foundations of quantum computing. They demonstrate that discussions of interpretations of quantum theory necessarily need to take into account field quantization. They also demonstrate the limitations of the role of wave equations in quantum theory, and caution us that superpositions of quantum states for the formation of qubits may be more limited than usually expected.     

我国航空制造业战略联盟模式演变及其管理模式研究

以资源依赖等理论为基础，通过分析国内外航空制造业战略联盟模式类型与更替，提炼出我国航空制造企业战略联盟“代加工-契约式-持股式”演变过程模型，并介绍了不同阶段模式的内涵与代表形态。面向战略联盟管理目标，提出了基于项目管理的战略联盟管理框架，及以矩阵式组织结构为静态治理框架、以契约机制、协同管理机制与文化融合机制为核心的运行体系。     

From canonical transformations to transformation theory, 1926–1927: The road to Jordan's Neue Begründung

We sketch the development from matrix mechanics as formulated in the Dreimännerarbeit of Born, Heisenberg, and Jordan, completed in late 1925, to transformation theory developed independently by Jordan and Dirac in late 1926. Focusing on Jordan, we distinguish three strands in this development: the implementation of canonical transformations in matrix mechanics (the main focus of our paper), the clarification of the relation between the different forms of the new quantum theory (matrix mechanics, wave mechanics, q-numbers, and operator calculus), and the generalization of Born's probability interpretation of the Schrödinger wave function. These three strands come together in a two-part paper by Jordan published in 1927, “On a new foundation [neue Begründung] of quantum mechanics.”     

露天矿土-岩复合边坡形态优化及失稳机理研究

针对露天矿土-岩复合边坡构成及失稳破坏模式的复杂多样性,以依兰露天矿为研究背景,应用极限平衡分析法和强度折减法分别对采场、排土场及二者构成的土-岩复合边坡稳定性进行了分析,优化边坡最终形态,研究其滑坡模式与机制。结果表明：当采场边坡角41°,与排土场相距80m时,复合边坡达最优形态,边坡破坏模式为在自重力作用下,坡面向外蠕变引发的圆弧滑动;极限平衡法简单、可靠,其与强度折减法相结合可弥补各自的不足,结果可靠,便于复合边坡的优化设计。     

Oxygen consumption and the evolution of order: negentropy criteria applied to the evolution of ants

Optimization of energy use by evolving organisms, predicted by theoretical extensions of the neo-Darwinian theory, i. contrasted with that of irreversible thermodynamics, which predicts an increase in orderliness and thus an increase in energy consumption per unit of biomass. We compared this index with estimates of social complexity among ant genera and species. Our results show that simple optimization models cannot explain experimental data, and that social complexity correlates differently with negentropy at different levels of analysis. Comparing the genera among Formicidae, workers (not colonies) from genera with highly social species are less negentropic than those of socially primitive ones. At the sub-generic level, social complexity correlated positively with negentropy among species, for major workers inAcromyrmex and for minor workers inAtta. The results illustrate the complexity of thermodynamic criteria in the study of evolution but also hint at their usefulness. In this case, they show that two different evolutionary routes to the complex Attini ant societies may exist.     

Changes in olfactory perception during the menstrual cycle

Summary The aim of the study was to find correlations between changes in olfactory sensitivity and the menstrual cycle. 14 young, healthy volunteers participated in the experiments. Subjects menstruated regularly and did not use oral contraceptives. Three odorants were investigated: phenylethyl alcohol, androstenone, and nicotine. Dilution series of the odorants were prepared, and presented to the subjects in order to determine the detection thresholds (triple forced choice). Additionally, the subjects' hedonic estimates of the odorants were measured, and mood states as well as hormonal levels of LH and estrogen were determined. Before the actual experiments started, subjects participated in three training sessions.One experiment was subdivided into 5 phases (two pre- and two postovulatory phases; one ovulatory phase). Only with regard to androstenone did trend analyses reveal a significant quadratic relationship between hedonic estimates and phases of the menstrual cycle, peaking at ovulation. Olfactory sensitivity was not significantly influenced by the menstrual cycle.     

T700／QY8911复合材料圆管轴压下能量吸收研究

采用T700／QY8911预浸料热压成型制作了复合材料圆柱管,对其进行了轴向压缩下能量吸收性能的试验。通过试验得到了峰值载荷、平均压溃载荷和比吸能率等主要能量吸收性能参数。试验结果表明,能量吸收性能及压溃破坏模式不仅与碳纤维材料性能有关,还与成型工艺及端部减薄这一薄弱环节设置密切相关;端部减薄薄弱环节的设置能有效地降低圆柱管在压溃过程中的峰值载荷,渐进地引发圆柱管压溃失效。建立了复合材料圆管轴向渐进损伤压缩有限元模型,通过计算得到了能量吸收性能的重要参数,计算结果与试验结果比较吻合说明了所采用的模拟方法是可行的。     

Changes in olfactory perception during the menstrual cycle

The aim of the study was to find correlations between changes in olfactory sensitivity and the menstrual cycle. 14 young, healthy volunteers participated in the experiments. Subjects menstruated regularly and did not use oral contraceptives. Three odorants were investigated: phenylethyl alcohol, androstenone, and nicotine. Dilution series of the odorants were prepared, and presented to the subjects in order to determine the detection thresholds (triple forced choice). Additionally, the subjects' hedonic estimates of the odorants were measured, and mood states as well as hormonal levels of LH and estrogen were determined. Before the actual experiments started, subjects participated in three training sessions. One experiment was subdivided into 5 phases (two pre- and two postovulatory phases; one ovulatory phase). Only with regard to androstenone did trend analyses reveal a significant quadratic relationship between hedonic estimates and phases of the menstrual cycle, peaking at ovulation. Olfactory sensitivity was not significantly influenced by the menstrual cycle.     

Physical methods for characterization of microbial surfaces

There are different concepts for explaining the adsorption of microorganisms to solid surfaces: the DLVO theory and the surface free energy. Basic aspects of both theories are discussed. Established methods for determining the surface properties of microbial cells are reviewed: Electrophoretic mobility, colloid titration, electrostatic interaction chromatography, bacterial adherence to hydrocarbons, partitioning in an aqueous two-phase system, hydrophobic interaction chromatography, contact angle measurement and X-ray photoelectron spectroscopy. They are discussed and classified according to their potential for the correlation of cell surface characteristics and adsorption behavior.