对我国社会保障水平“度”的辩证思考

文章对如何正确把握我国社会保障水平的“度” ,坚持其“适度”原则进行了探讨。首先简要说明了制约“度”的条件因素 ,接着重点论述了“度”是我国社会保障质与量的统一 ;质与量的关系是“一”和“多”的关系。最后指出应从社会保障水平“度”的进展过程中 ,动态把握和保持“最佳度”。

Regulated Gene Expression with Promoters Responding to Inducers

Genetically engineered transgenic animals and plants have proven to be extremely useful for analyzing biochemical and developmental processes.Promoters responding to chemical inducers will be powerful tools for basic research in molecular biology and biotechnological applications.Various chemical inducible systems based on activation and inactivation of the target gene had been described.The transfer of regulatory elements from prokaryotes,insects,and mammals has opened new avenues to construct chemically inducible promoters that differ in their ability to regulate the temporal and spatial expression patterns,and this will dramatically increase the application of transgenic technology.This review provides an overview on regulation of gene expression,promoter activating systems,promoter inactivation systems,inducible gene over expression,and inducible anti suppression.

Causal Stability Conditions for General Relativistic Spacetimes

A brief overview of some open questions in general relativity with important consequences for causality theory is presented, aiming to a better understanding of the causal structure of the spacetime. Special attention is accorded to the problem of fundamental causal stability conditions. Several questions are raised and some of the potential consequences of recent results regarding the causality problem in general relativity are presented. A key question is whether causality violating regions are locally allowed. The new concept of almost stable causality is introduced; meanwhile, related conditions and criteria for the stability and almost stability of the causal structure are discussed.

Experimental studies on the P-T stability conditions and influencing factors of gas hydrate in different systems

The P-T stability conditions of gas hydrate in different systems （i.e., solution, silica sand, and marine sediment） were studied using multi-step decomposition method with our experimental equipment. The effects of different ions with various concentra- tions and sediment grains on the P-T stability conditions of gas hydrate were investigated. The results show that different ions have different influences on the phase equilibrium of gas hydrate. However, the influence of ions is in a similar trend： the larg- er the concentration, the bigger the P-T curve shifts to the left. For the silica sand, the influence of pore capillarity of coarse particles （〉 460 ~tm） can be negligible. The P-T curve measured in coarse silica is in agreement with that in pure water. How- ever, the influence of pore capillarity of fine particles （〈 35 μm） is significant. The maximum reduction value of temperature is 1.5 K for methane hydrate under stable state. The sediment from the South China Sea significantly affects the P-T stability conditions of methane hydrate, with an average reduction value of 1.9 K within the experimental conditions. This is mainly the result of both the pore water salinity and the pore capillarity of sediment. Because the pore water salinity is keeping diluted by the fresh water released from hydrate dissociation, the measured P-T stability points fall on different P-T curves with the de- creasing salinity.

A New Plan and Coordination Strategy for Robot System Based on State Space

This paper proposes a general plan and coordination strategy for robot system. The state space for robot system is constructed according to the task requirement and system characteristic. Reachable state of the system is figured out by the system’s internal and external constraints. Task plan and coordination are then transformed as trajectory solving problem in the state space, by which the realizable conditions for the given task are discussed. If the task is realizable, the optimal strategy for task execution could be investigated and obtained in state space. Otherwise, it could be transformed to be realizable via adjusting the system configuration and/or task constraint, and the transformation condition could also be determined. This contributes to design, plan, and coordination of the robotic tasks. Experiments of the manipulator path planning and multi-robot formation movement are conducted to show the validity and generalization of the proposed method.

Adiabatic approximation in PT-symmetric quantum mechanics

In this paper, we present a quantitative sufficient condition for adiabatic approximation in PT-symmetric quantum mechanics,which yields that a state of the PT-symmetric quantum system at any time will remain approximately in the m-th eigenstate up to a multiplicative phase factor whenever it is initially in the m-th eigenstate of the Hamiltonian. In addition, we estimate the approximation errors by the distance and the fidelity between the exact solution and the adiabatic approximate solution to the time evolution equation, respectively.

Comprehension of functional support by enculturated chimpanzees Pan troglodytes

Studies of causal understanding of tool relationships in captive chimpanzees have yielded disparate findings, particularly those reported by Povinelli ＆ colleagues （2000） for tool tasks by laboratory chimpanzees. The present set of experiments tested nine enculturated chimpanzees on three versions of a support task, as described by Povinelli （2000）, during which food re- wards were presented in different experimental configurations. In Experiment 1, stimulus pairs included a choice between a cloth with a reward on the upper right comer or with a second reward off the cloth, adjacent to a comer, with the second pair comprised of a cloth with food on the upper right comer, and a second cloth with the reward on the substrate, partially covered. All subjects were successful with both test conditions in Experiment 1. In a second study, the experimental choices included one of two possi- ble correct options, paired with one of three incorrect options, with the three incorrect choices all involving varying degrees of perceptual containment. All nine chimpanzees scored significantly above chance across all six conditions. In Experiment 3, four unique conditions were presented, combining one of two possible correct choices with one of two incorrect choices. Six of the subjects scored significantly above chance across the four conditions, and group performance on individual conditions was also significant. Superior performance was demonstrated by female subjects in Experiment 3, similar to sex differences in tool use previously reported for wild chimpanzees and some tool tasks in captive chimpanzees. The present results for Experiments 2 ＆ 3 were significantly differed from those reported by Povinelli et al. （2000） for laboratory-born, peer-reared chimpanzees. One contribution towards the dramatic differences between the two study populations may be the significant rearing and housing differences of the chimpanzee groups. One explanation is that under conditions of enculturation, rich social interactions with humans and conspecifics, as well as active exploration of artifacts, materials, and other aspects of their physical environment had a significant impact on the animals＇ ability to recognize the support relationships among the stimulus choices. Overall, the present findings provide strong support for the hypothesis that our chimpanzee subjects based their responses on an understanding of functional support which represented one facet of their folk physics repertoire [Current Zoology 57 （4）： 429-440, 2011].