微悬臂梁致动器动态性能分析

考虑环境的影响,无铅材料在微机系统中的应用是微器件的一种趋势。本文建立一个包含多层的无铅压电薄膜微致动器的悬臂梁理论模型和有限元模型,利用理论模型来模拟该微致动器第一模态的动态致动性能,同时利用有限元模型来验证理论模型的正确性。并且通过模拟可知,微悬臂梁致动器的谐振频率随着梁长的变化而降低;挠度随着外加电压的增加而增大。

IPMC人工肌肉的特性及其应用

介绍了IPMC人工肌肉致动器的制备、致动特性和应用 。

致动型疲劳性骨折理疗临床实践探讨

报告37例用物理治疗致动型疲劳性骨折临床实践总结，结果表明：物理治疗可促进骨痂生长，功能恢复，对植物神经，运动神经和肌肉修复代偿功能等都有明显作用，典型病案中的运动员患者，在物理治疗致动型疲劳性骨折愈合后，都创造了比患该症前更好的运动成绩，强调了只要坚持用物理治疗致型疲劳性骨折都取得较明显的治疗效果，提出如何在运动员大负荷运动后，利用物理治疗促进身体机能恢复，减少致动型劳损。

Embodied Meaning in Comprehending Abstract Chinese Counterfactuals

Embodied cognition theories propose that language comprehension triggers a sensorimotor system in the brain.However,most previous research has paid much attention to concrete and factual sentences,and little emphasis has been put on the research of abstract and counterfactual sentences.The primary challenges for embodied theories lie in elucidating the meanings of abstract and counterfactual sentences.The most prevalent explanation is that abstract and counterfactual sentences are grounded in the activation of a sensorimotor system,in exactly the same way as concrete and factual ones.The present research employed a dual-task experimental paradigm to investigate whether the embodied meaning is activated in comprehending action-related abstract Chinese counterfactual sentences through the presence or absence of action-sentence compatibility effect(ACE).Participants were instructed to read and listen to the action-related abstract Chinese factual or counterfactual sentences describing an abstract transfer word towards or away from them,and then move their fingers towards or away from them to press the buttons in the same direction as the motion cue of the transfer verb.The action-sentence compatibility effect was observed in both abstract factual and counterfactual sentences,in line with the embodied cognition theories,which indicated that the embodied meanings were activated in both action-related abstract factuals and counterfactuals.

Discoursal Features of Teachers＇ Instructional Discourse

Teachers＇ discourse is teachers＇ language used in the classroom. Teachers＇ instructional discourse, a sub-category of teachers＇ discourse, is the medium that teachers use to achieve the teaching and learning goals It is not only the means for teachers to organize teaching activities, but is also taken as the model language by students. This paper examines teachers＇ instructional discourse by focusing on its discoursal features. Drawing on the theories and methods in discourse analysis, four categories of discoursal features in teachers＇ instructional discourse are proposed. They are communicativeness, authenticity, coherence, and grammaticality and appropriateness. The four discoursal features will provide a framework for analyzing teachers＇ instructional discourse in the language classroom

Motor Compatibility Effect on the Comprehension of Complex Manual Action Sentences in L2:An ERP Study

Embodiment theories proposed that the comprehension of language involves sensory-motor simulation in the brain.The present study examined the brain response to motor compatibility effect in comprehending action-related linguistic materials for participants learning Chinese as a second language(L2).In this study,participants are required to read action-related sentences describing an agent performing two manual actions simultaneously or sequentially by manipulating temporal conjunctions.The sentences with simultaneous actions are marked by Chinese parallel structure一边……一边……(“while”)showing non-congruent motor condition while the sequential action sentences are marked by先……然后……(“after”)showing congruent motor condition.Event-Related Potentials(ERPs)were recorded with the second verb phrase.A larger fronto-central late positivity was observed for the sentences with simultaneous actions rather than the sentences with sequential actions due to body constraints,revealing that late L2 Chinese learners integrate embodied knowledge while processing action-related complex sentence despite demanding more cognitive resources,and longer processing time.

Characteristic of Intelligent Air Bag Venting Structure Actuating by Electrostrictive Stack Actuator

In this paper the conception of smart materials and structures is firstly combined with research of air bag,and the main theory of self adapting cushioning of intelligent air bag is expatiated.The intelligent venting structure is the main part affecting the cushioning result.Electrostrictive material was found having big force,high response speed and wide linearity,and it is fit to utilize in intelligent venting structure. The characteristic of the dynamic response and cushioning actuating of an electrostrictive stack actuator is analyzed,and the result of the computer simulation of the fuzzy control to intelligent venting structure is given.It is concluded that intelligent venting structure has good actuating characteristic and can satisfy the need of intelligent air bag.

Barbed congruence of the asymmetric chi calculus

The ehi calculus is a model of mobile processes. It has evolved from the pi-calculus with motivations from simplification aml communication-as-cut-eliminatinn. This paper studies the ehi calculus in the framework incorporating asymmetric communication. The major feature of the calculus is the identification of two actions： x/x and τ. The investigalion on the barbed bisimilarity shows how the property affects the observational theory. Based on the definition of the barbed bisimilarity, the simulation properties of the barbed bisimilarity are studied. It shows that the algebraic properties of the barbed bisimiilarity have changed greatly compared with the chi calculus.Although the definition of the barbed bisimilarity is very simple, the properly of closeness under contexts makes it difficuh to understand the barbed bisimilarity directly. Therefore an open style definition of the barbed bisimilarity is given, which is a context free description of barbed bisimilarity. Its definition is complex, but it is a well-behaved relation for it coincides with the barbed bisimilarity. It also helps to build an axiomatization system for the bathed congruence. Besides the axioms for the strong barbed bisimilarity, the paper proposes a new tau law and four new update laws for the barbed congruence. Both the operational and algebraic properties of the enriched calculus improve the understanding of the bisimulation behaviors of the model.

Drug-induced liver injury in inflammatory bowel disease: 1-year prospective observational study

To analyze 1-year liver injury burden in inflammatory bowel disease (IBD) patients.METHODSDuring a 6-mo inclusion period, consecutive IBD cases having a control visit at IBD center were included. Basic demographics, IBD phenotype and IBD treatment were recorded on entry. Aminotransferase (AT) activities of ALT, AST, ALP and gamma-glutamyl transpeptidase (GGT) were measured at baseline, 3 mo prior to study entry and prospectively every 3 mo for 1 year. Liver injury patterns were predefined as: Grade 1 in ALT 1-3 × upper limit of normal (ULN), grade 2 in ALT > 3 × ULN, hepatocellular injury in ALT > 2 × ULN, cholestatic injury in simultaneous GGT and ALP elevation > ULN. Persisting injury was reported when AT elevations were found on > 1 measurement. Risk factors for the patterns of liver injury were identified among demographic parameters, disease phenotype and IBD treatment in univariate and multivariate analysis. Finally, implications for the change in IBD management were evaluated in cases with persisting hepatocellular or cholestatic injury.RESULTSTwo hundred and fifty-one patients were included having 917 ALT and 895 ALP and GGT measurements. Over one year, grade 1 injury was found in 66 (26.3%), grade 2 in 5 (2%) and hepatocellular injury in 16 patients (6.4%). Persisting hepatocellular injury was found in 4 cases. Cholestasis appeared in 11 cases (4.4%) and persisted throughout the entire study period in 1 case. In multivariate analysis, hepatocellular injury was associated with BMI (OR = 1.13, 1.02-1.26), liver steatosis (OR = 10.61, 2.22-50.7), IBD duration (1.07, 1.00-1.15) and solo infliximab (OR = 4.57, 1.33-15.7). Cholestatic liver injury was associated with prior intestinal resection (OR = 32.7, 3.18-335), higher CRP (OR = 1.04, 1.00-1.08) and solo azathioprine (OR = 10.27, 1.46-72.3). In one case with transient hepatocellular injury azathioprine dose was decreased. In 4 cases with persisting hepatocellular injury, fatty liver or alcohol were most likely causes and IBD treatment was pursued without change. In the case with persisting cholestatic injury, no signs of portal hypertension were identified and treatment with infliximab continued.CONCLUSIONLiver injury was frequent, mostly transient and rarely changed management. Infliximab or azathioprine were confirmed as its risk factors indicating the need for regular AT monitoring.

Advances in Biodegradation of Aflatoxins

Aflatoxins are secondary metabolites of fungi such as Aspergillus flavus and Aspergillus parasiticus. They are one of the contaminants most common in food and feed, with high toxicity and carcinogenicity. Aflatoxins usually enter animal body together with feed and then enter human body by food chain, thereby seriously threatening human health. In recent years, the degradation of aflatoxins has become a hot research topic. This study overviewed the characteristics and detoxification ways of aflatoxins, specifically for the advances in biodegradation and degradation products of aflatoxins.

Effects of Spontaneously Generated Coherence on Intensity-Intensity Correlation in a Driven Y-Type Atom

In this paper,we investigate the spontaneously generated coherence(SGC) effects on the fluorescence fields intensity-intensity correlation in a resonant driven four-level Y-type atomic system.By using a strong control field, in the absense of SGC effects,strong correlation and anticorrelation fluorescence photons can be produced from two ladder transitions in this system respectively.However,in the presence of SGC effects,the fluorescence fields correlation properties are reversed for the two transitions.The above phenomena can be traced to the quantum destructive or constructive interference in terms of dressed states.

Influences of Injection Barrier and Mobility on Recombination Rate and Zone in OLEDs

The luminous efficiency of organic light-emitting devices depends on the recombination probability of electrons injected at the cathode and holes at the anode. A theoretical model to calculate the distribution of current densities and the recombination rate in organic single layer devices is presented taking into account the charge injection process at each electrode, charge transport and recombination in organic layer. The calculated results indicate that efficient single-layer devices are possible by adjusting the barrier heights at two electrodes and the carrier mobilities. Lowering the barrier heights can improve the electroluminescent(EL) efficiency pronouncedly in many cases, and efficient devices are still possible using an ohmic contact to inject the low mobility carrier, and a contact limited contact to inject the high mobility carrier. All in all, high EL efficiency needs to consider sufficient recombination, enough injected carriers and well transport.

Consistent Distribution of Stress before Strong Earthquake from Focal Mechanisms

At some stage of a strong earthquake preparation, the focal mechanisms of small earthquakes have roughly the same direction with the tectonic stress field. According to this feature, we define the angle between P, B and T axis of focal mechanisms and the three stress axes of tectonic stress field as the consistency parameter a in studying the dynamic changes of stress fields in earthquake preparation areas. We mainly analyze the changes of the consistency parameter a of the Mw8. 3 Knril island arc earthquake and the Mw8. 4 Peru earthquake. Our study shows that before the strong earthquakes, the earthquake area saw a low consistency, and the focal mechanisms of a series of small earthquakes had small differences in the directions with the tectonic stress field, which means the foreshocks were under the control of the stress field. On the other hand, a higher consistency means the focal mechanisms of their aftershocks are scattered and have big differences in the directions with the tectonic field, which indicate that the control of background stress field starts weakening.

Comparison and Evaluation of Three Animal Models for Studyingthe Pathogenicity of Staphylococcus epidermidis

In order to compare and evaluate three animal models for studying the pathogenicity of Staphylococcus epidermidis strains, three experimental animal models, namely, murine intra-venous LD 50, mouse foreign body infection and rat central venous catheter (CVC) infection models were used to assess the relative virulence of two S. epidermidis strains, ATCC 12228 and 97-337. The results from three animal models were comparable, indicating S.epidermidis 97-337 was more virulent than strain ATCC 12228. The rat CVC infection model best mimicked the conditions of clinical patients with intra-venous catheters, and more information could be obtained from this model. We conclude that different in vivo models serve for different purposes, and the rat CVC infection model is most suitable for studying specific characteristics of catheter related infections caused by S. epidermidis strains.

Bose Description of Pauli Spin Operators and Related Coherent States

Using both the fermionic-kike and the bosonic-like properties of the Paulispin operators σ_+, σ_-, and σ_z we discuss the derivation of Bose description of the Pauli spinoperators originally proposed by Shigefumi Naka, and deduce another new bosonic representation ofPauli operators. The related coherent states, which are nonlinear coherent state and coherent spinstates for two spins, respectively, are constructed.

Unified Symmetry of Nonholonomic Mechanical Systems of Non-Chetaev＇s Type with Unilateral Constraints

The definition and the criterion for a unified symmetry of nonholonomic mechanical systems of non- Chetaev＇s type with unilateral constraints are presented based on the total time derivative along the trajectory of the system. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced froth the unified symmetry, is obtained. An example is given to illustrate the application of the results.

Structure design and characteristics analysis of a cylindrical giant magnetostrictive actuator for ball screw preload

In order to achieve automatic adjustment of the double-nut ball screw preload, a magnetostrictive ball screw preload system is proposed. A new cylindrical giant magnetostrictive actuator （CGMA）, which is the core component of the preload system, is developed using giant magnetostrictive material （GMM） with a hole. The pretightening force of the CGMA is determined by testing. And the magnetic circuit analysis method is introduced to calculate magnetic field intensity of the actuator with a ball screw shaft. To suppress the thermal effects on the magnetostrictive outputs, an oil cooling method which can directly cool the heat source is adopted. A CGMA test platform is established and the static and dynamic output characteristics are respectively studied. The experimental results indicate that the CGMA has good linearity and no double-frequency effect under the bias magnetic field and the output accuracy of the CGMA is significantly improved with cooling measures. Although the output decreased with screw shaft through the actuator, the performance of CGMA meets the design requirements for ball screw preload with output displacement more than 26 μm and force up to 6200 N. The development of a CGMA will provide a new approach for automatic adjustment of double-nut ball screw preload.

Toxicity of Chlorpyrifos and Dimethoate to the Ciliate Urostyla grandis, with Notes on Their Effects on Cell Ultrastructure

Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, substantial attention has been given to the effects of pesticides on vertebrate species and, to a lesser extent, species of zooplankton. The present study was designed to show that the fission time effective concentration in ciliates is a potential aquatic detection index for environmental monitoring. The ciliate Urostyla grandis was treated with doses of chlorpyrifos and dimethoate. After exposed to the pesticides, the LC_(50)(i.e., concentration that killed 50% of the ciliate cells within 24 h) values were 0.029 mg L^(-1) for chlorpyrifos and 0.0685 mg L^(-1) for dimethoate. The fission time effective concentrations after 168 h of exposure were 0.0075–0.0093 mg L^(-1) for chlorpyrifos and 0.2640–0.2750 mg L^(-1) for dimethoate. These results show that the fission time effective concentration is lower than the LC_(50) value in ciliates, indicating that fission time effective concentration is more suitable than the LC_(50) value for environmental monitoring using ciliates. The effects of chlorpyrifos and dimethoate on ciliate cell ultrastructures included agglutination of chromatin in the macronucleus, protruded and discontinuous macronuclear and micronuclear membranes, loss of integrity of mitochondrial membranes and contents, and abscission and deformation of the adoral zone of membranelles.

Construction of Coherence Identity in Sports： The Case of the ＂Grand Raid＂ Running Race in Nature of Reunion Island

Sportsmen who engage in sports in open natural settings are not always coherent in their behaviors towards environment; in fact, they seldom are. From survey made on a sport event the ＂Grand Raid 2010＂, a foot race in mountains of Reunion Island, the authors discover that these sportsmen are not the good activists fighting for a green planet that they imagine they are. The authors try to explain the disparity between the perception that they have of themselves and the reality of their practices.

Moving Target Tracking Based on LogGabor Wavelet and Mean-shift Algorithm

Tracking moving target from image or video sequence is a hot research topic in computer vision. An algorithm based on LogGabor wavelet and Mean-shift has been proposed for moving target tracking under fixed camera setting and complicated environment. Phase coherency of LogGabor wavelet facilitates to extract the edge of moving target and check noise. According to the edge detection,the starting location of Mean-shift can be estimated using the target center coordinate. Eventually,a real-time moving target can be extracted by doing iterative matching pursuit,and experimental results proved the effectiveness of the method proposed.