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关键词： 智能包装   识别   判断   自适应控制   信息干预  

摘要： 智能包装通过对包装材料的更新换代升级、通过改造包装结构、通过整合被包装物信息管理,实现被包装物的人性化的智能化的要求、目的或效能。智能包装可划分为功能材料型智能包装、功能结构型智能包装及信息型智能包装三种类型。

关键词： 工业气体   包装运输   危险性   TDG   分类鉴定   标签  

摘要： 综述了工业气体在运输过程中的危险性,研究了联合国《关于危险货物运输的建议书规章范本》(TDG)中对工业气体包装运输的危险性分类。在此基础上,提出了对工业气体进行正确分类的思路,最终依据提出的思路和TDG的标准对工业气体样品进行了分类鉴定。

关键词： Task complexity   Task sequence   Self-efficacy belief   Learning strategy use   Vocabulary learning   SELF-EFFICACY   DICTIONARY USE   ACHIEVEMENT   STUDENTS   ACQUISITION   STRATEGIES  

摘要： In the field of second and foreign language learning, how various task characteristics affect language learning has been the focus of many recent studies. Much of this research examined the relationship between task characteristics and task performance without fully taking into account learner related variables. The present study aimed to assess task complexity and sequence in relation to the learner related variables drawn from the social cognitive perspective of self-regulated learning, i.e. self-efficacy beliefs and frequency of learning strategy use, as they were applied to two versions of vocabulary learning from reading tasks. The tasks designed for the present study were based on the componential framework for second language task design. With tasks and task sequence counterbalanced, 146 first-year university students (mean age = 18.59 years) were randomly assigned to one of four groups. Results reveal a significant effect of task sequence on vocabulary learning self-efficacy beliefs, frequency of learning strategy use and task performance, and a significant interaction effect of sequence with task complexity. Findings are discussed in terms of complex interactions between task and learner factors.

关键词： Computer security   malware   control flow   structural classification   structured control flow   unpacking   GENERATION  

摘要： Signature-based malware detection systems have been a much used response to the pervasive problem of malware. Identification of malware variants is essential to a detection system and is made possible by identifying invariant characteristics in related samples. To classify the packed and polymorphic malware, this paper proposes a novel system, named Malwise, for malware classification using a fast application-level emulator to reverse the code packing transformation, and two flowgraph matching algorithms to perform classification. An exact flowgraph matching algorithm is employed that uses string-based signatures, and is able to detect malware with near real-time performance. Additionally, a more effective approximate flowgraph matching algorithm is proposed that uses the decompilation technique of structuring to generate string-based signatures amenable to the string edit distance. We use real and synthetic malware to demonstrate the effectiveness and efficiency of Malwise. Using more than 15,000 real malware, collected from honeypots, the effectiveness is validated by showing that there is an 88 percent probability that new malware is detected as a variant of existing malware. The efficiency is demonstrated from a smaller sample set of malware where 86 percent of the samples can be classified in under 1.3 seconds.

关键词： EARTHWORM BURROW SYSTEMS   QUANTITATIVE-ANALYSIS   PHYSICAL-PROPERTIES   WATER-CONTENT   ROOT-SYSTEM   PLANT-ROOTS   3-DIMENSIONAL VISUALIZATION   HYDRAULIC-PROPERTIES   ASSISTED TOMOGRAPHY   IMAGE-ANALYSIS  

摘要： Soil systems are characterized by the spatial and temporal distribution of organic and mineral particles, water and air within a soil profile. Investigations into the complex interactions between soil constituents have greatly benefited from the advent of non-invasive techniques for structural analysis. In this paper we present a review of the application of one such technique, X-ray computed tomography (CT), for studies of undisturbed soil systems, focusing on research during the last 10years in particular. The ability to undertake three-dimensional imaging has provided valuable insights regarding the quantitative assessment of soil features, in a way previously unachievable because of the opaque nature of soil. A dynamic approach to the evaluation of soil pore networks, hydro-physical characteristics and soil faunal behaviour has seen numerous scanning methodologies employed and a diverse range of image analysis protocols used. This has shed light on functional processes across multiple scales whilst also bringing its own challenges. In particular, much work has been carried out to link a soil's porous architecture with hydraulic function, although new technical improvements allowing the characterization of organic matter and the influence of soil biota on structural development are showing great promise. Here we summarize the development of X-ray CT in soil science, highlight the major issues relating to its use, outline some of the applications for overcoming these challenges and describe the potential of future technological advances for non-invasive soil characterization through integration with other complementary techniques.

关键词： CONNECTION DOMAIN   CRYSTAL-STRUCTURE   COMPLEX   N348I   MUTAGENESIS   MUTATIONS   3'-AZIDO-3'-DEOXYTHYMIDINE   RESISTANCE   INHIBITORS   SUBDOMAIN  

摘要： Recent crystallographic analysis of p66/p51 human immuno-deficiency virus (HIV) type 1 reverse transcriptase (RT) complexed with a non-polypurine tract RNA/DNA hybrid has illuminated novel and important contacts between structural elements at the C terminus of the noncatalytic p51 subunit and the nucleic acid duplex in the vicinity of the ribonuclease H (RNase H) active site. In particular, a short peptide spanning residues Phe-416-Pro-421 was shown to interact with theDNA strand, cross the minor groove of the helix, and then form Van der Waals contacts with the RNA strand adjacent to the scissile phosphate. At the base of the adjoining alpha-helix M', Tyr-427 forms a hydrogen bond with Asn-348, the latter of which, when mutated to Ile, is implicated in resistance to both nucleoside and non-nucleoside RT inhibitors. Based on our structural data, we analyzed the role of the p51 C terminus by evaluating selectively mutated p66/p51 heterodimers carrying (i) p51 truncations that encroach on alpha-M', (ii) alterations that interrupt the Asn-348-Tyr- 427 interaction, and (iii) alanine substitutions throughout the region Phe-416-Pro-421. Collectively, our data support the notion that the p51 C terminus makes an important contribution toward hybrid binding and orienting the RNA strand for catalysis at the RNase H active site.

关键词： 委托理财合同   合同形式   电子合同   法律效力  

摘要： 委托理财合同作为商事性理财合同在其有效性认定上具有很大争议,而在信息化技术高度发展的今天,新型合同形式对合同的有效性认定影响很大,尤以电子合同为典型。由此需要根据委托理财合同的特殊性进行相应的合同形式规则设计。

关键词： Serotonin transporter gene   Posttraumatic stress disorder   Trauma   Disaster   DISASTER VICTIMS SPEAK   FIT INDEXES   5-HTTLPR POLYMORPHISM   DYSPHORIC AROUSAL   BIASED ATTENTION   PROMOTER REGION   5-FACTOR MODEL   PTSD SYMPTOMS   DISORDER   GENE  

摘要： Background: Little is known about the specificity of the interaction of serotonin transporter 5-HTTLPR genotype x trauma exposure in relation to contemporary structural models of PTSD symptomatology, which suggest that 4- or 5-factor models provide a better representation of the phenotypic expression of this disorder. Methods: One hundred forty-nine respondents of a representative sample of adults affected by Hurricane Ike were interviewed 2-5 months after this 2008 disaster. Results: After adjustment for age, sex, and ancestral proportion scores, the interaction of 5-HTTPLR genotype x trauma exposure was significantly associated with both severity (beta=40, p < .001) and probable diagnosis (Wald=4.55, p=.033; odds ratio=3.81, 95% CI=1.11-13.03) of Ike-related PTSD. Respondents with the low-expression variant of the 5-HTTPLR polymorphism (S allele carriers) who were highly exposed to Hurricane Ike reported significantly greater severity of PTSD symptoms and were more likely to screen positive for PTSD than respondents homozygous for the L allele who were highly exposed to Hurricane Ike. Confirmatory factor analyses revealed that a 5-factor model of intercorrelated re-experiencing, avoidance, numbing, dysphoric arousal, and anxious arousal symptoms provided the best structural representation of PTSD symptomatology. The 5-HTTPLR genotype x exposure interaction was significant only for anxious arousal (beta=.44, p<.001) and re-experiencing (beta=.35, p<.001) symptoms, but not avoidance, numbing, or dysphoric arousal symptoms (all beta s <=.20, all ps > .13). Limitations: The small sample size and employment of self-report measures may limit generalizability of these findings. Conclusions: Results of this pilot study suggest that the low-expression variant of the 5-HTTLPR polymorphism modifies risk for PTSD, but that this effect may be specific to anxious arousal and re-experiencing symptoms. Published by Elsevier B.V.

关键词： TU857   电梯系统   检验  

摘要： 本文通过研究EVA-625系统的各种测量数据，证明大大提高电梯检验检测的准确性和权威性，增加了乘客的乘坐舒适度，保证了人民的生命财产安全，减轻了电梯检验的负担，行之有效的提高了工作效率。确保电梯安全运行，已成为各级特种设备监察部门急需解决的重要课题。

关键词： DNA损伤检验点   ATM—chk2通路   衰老  

摘要： 目的分析DNA损伤检验点ATM-chk2通路对影响衰老的作用机制。方法选择SD大鼠4个月龄、12个月龄、20个月龄和28个月龄各10只,分别取4个月龄、12个月龄、20个月龄和28个月龄大鼠的骨髓组织进行ATM-chk2通路的观察,并对结果进行分析。结果 4个月龄、12个月龄、20个月龄和28个月龄SD大鼠的ATM基因表达随着月龄增加,呈逐渐下降趋势,不同月龄大鼠间比较,差异具有显著性(P<0.05);ATM-chk2通路基因蛋白表达呈逐渐上升趋势,组间比较差异具有显著性(P<0.05)。结论 ATM基因表达及ATM-chk2通路基因蛋白表达水平和大鼠月龄直接相关,年龄越大ATM基因表达日渐降低,ATM-chk2通路基因蛋白表达呈逐渐上升趋势。