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1.
Summary 2-Furyl vinyl ketone was polymerised using anionic, cationic and free-radical initiators. Yields and molecular weights varied with the type of activation. Whereas radical polymerisation gave a product possessing a regular vinylic structure, other kinds of units were detected in the polymers prepared with anionic and cationic catalysts.  相似文献   
2.
When hooded rats with bilateral lesions of Krieg's Area 7 (parietal cortex) were trained to locomote toward visual targets in a runway, they ran less accurately than did controls, although unilaterals ran accurately. When flashing lights were presented unexpectedly during their run, bilateral parietals were less disrupted than were controls, but they failed to show total neglect. Unilateral parietals turned toward distracters on either side but turned preferentially toward distracters contralateral to the intact hemisphere, particularly when distracters occurred bilaterally and simultaneously. Effects due to the omission of expected distracters were similar in parietals and controls. Rat parietal cortex is not essential for the redirection of attention to stimuli notable for their unexpected presence or absence, but parietal cortex may resolve interhemispheric competition. Results suggest a homology between parietal cortex in rat and primate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Based on the analysis of “real” Second Life meetings data, in educational and professional settings, our objective is to understand the actual uses of this kind of Virtual World and more particularly, the interactive frames constructed in SL meetings and their interrelation with uses of communication media. The originality of our analytical framework stems from the combination of two perspectives: a third view perspective based on analyses of observational data and a first view perspective based on users’ reports on their experience in SL. Our results highlight: boundaries between serious and recreational registers; avatar’s expression and attribution of feelings to the person “behind”; spatial positioning as indicators and constructors of roles and engagement; management of communication fluidity and joint focus; narrowing of communication media used for task focus content; emerging mediation role for management of fractured exchanges.  相似文献   
4.
This paper deals with task scheduling, where each task is one particular iteration of a DO loop with partial loop-carried dependencies. Independent iterations of such loops can be scheduled in an order different from the one of classical serial execution, so as to increase program performance.The approach that we present is based both on the use of a directive added to the High Performance Fortran (HPF2) language, which specifies the dependencies between iterations, and on inspector/executor support, implemented in the CoLUMBO library, which builds the task graph and schedules tasks associated with iterations. We validate our approach by showing results achieved on an IBM SP2 for a sparse Cholesky factorization algorithm applied to real problems.  相似文献   
5.
We have identified and cloned the cDNAs encoding two odorant-binding proteins (OBPs) from the American palm weevil (APW) Rhynchophorus palmarum (Coleoptera, Curculionidae). Degenerate primers were designed from the N-terminal sequences and were used in polymerase chain reaction (PCR) in order to obtain full-length sequences in both males and females. In both sexes, two different cDNAs were obtained, encoding 123 and 115 amino acid-deduced sequences. Each sequence showed few amino acid differences between the sexes. The proteins were named RpalOBP2 and RpalOBP4 for male, RpalOBP2' and RpalOBP4' for female, with the types 2 and 4 presenting only 34% identities. These proteins shared high identity with previously described coleopteran OBPs. In native gels, RpalOBP2 clearly separated into two bands and RpalOBP4 into three bands, suggesting the presence of several conformational isomers. Thus, OBP diversity in this species may rely on both the presence of OBPs from different classes and the occurrence of isoforms for each OBP.  相似文献   
6.
Cellulose nanocrystals (CNC) were successfully grafted with a low molecular weight poly(butylene glutarate) through an in situ polymerization procedure. The grafting treatment decreased the CNC hydrophilic character and increased the onset of their thermal degradation by approximately 20°C, thus increasing the possibilities of CNC application. Composites of grafted and nongrafted CNC with a poly(butylene‐adipate‐co‐terephthalate) (PBAT) matrix were prepared by melt extrusion. The CNC addition led to an increase of 50% of the tensile elastic modulus of the PBAT. In addition, dynamic mechanical thermal analysis showed that the composite with CNC retained its high modulus even at temperatures far above the glass transition temperature of PBAT. At 60°C the storage modulus of the composite with CNC was approximately 200% higher than that of the pure PBAT. Thus, in this work, nanocomposites of improved properties were obtained through a combination of in situ polymerization and melt extrusion. POLYM. ENG. SCI., 56:1339–1348, 2016. © 2016 Society of Plastics Engineers  相似文献   
7.
This study aimed to focus on medical knowledge representation and reasoning using the probabilistic and fuzzy influence processes, implemented in the semantic web, for decision support tasks. Bayesian belief networks (BBNs) and fuzzy cognitive maps (FCMs), as dynamic influence graphs, were applied to handle the task of medical knowledge formalization for decision support. In order to perform reasoning on these knowledge models, a general purpose reasoning engine, EYE, with the necessary plug-ins was developed in the semantic web. The two formal approaches constitute the proposed decision support system (DSS) aiming to recognize the appropriate guidelines of a medical problem, and to propose easily understandable course of actions to guide the practitioners. The urinary tract infection (UTI) problem was selected as the proof-of-concept example to examine the proposed formalization techniques implemented in the semantic web. The medical guidelines for UTI treatment were formalized into BBN and FCM knowledge models. To assess the formal models’ performance, 55 patient cases were extracted from a database and analyzed. The results showed that the suggested approaches formalized medical knowledge efficiently in the semantic web, and gave a front-end decision on antibiotics’ suggestion for UTI.  相似文献   
8.
The effect of ripening conditions (two temperatures, 9 °C and 13 °C, and two relative humidities 93% and 97%) on the growth of Listeria monocytogenes and other microbial populations was evaluated in the cores and rinds of uncooked pressed type cheeses prepared with pasteurised milk and inoculated either with Streptococcus thermophilus only or with an anti-listerial consortium. Regardless of temperature and relative humidity (RH), inhibition by the anti-listerial consortium was stronger in the cheese cores than in the rinds. Temperature had no significant effect on L. monocytogenes counts in cores or rinds. However, at the beginning of ripening in the consortium cheese, L. monocytogenes growth was more strongly inhibited at 13 °C than at 9 °C. Regardless of inoculation type and ripening temperature, counts of L. monocytogenes were significantly lower in the cores and rinds of cheeses ripened at 93% than at 97% RH. Lactobacilli counts were higher at 13 °C than at 9 °C and at 93% than at 97% RH. Lactobacilli can help to inhibit L. monocytogenes by catabolising galactose and producing lactate. Further investigations will be needed to evaluate the effect of ripening at 13 °C and 93% RH on the sensorial properties of cheese.  相似文献   
9.
The mechanical characterization of ceramics can be very challenging. Depending on their composition and fabrication process, ceramic materials may exhibit at room temperature different types of mechanical behaviours, ranging from linear elastic to quasi-brittle, like rocks, concrete or plasters. At elevated temperature, they may present a non-linear behaviour, due for instance to the presence of a vitreous phase. However, estimating the evolution of their behaviour from room temperature to elevated temperature is a challenging topic, especially when there is an asymmetry between tension and compression. A methodology based on Digital Image Correlation is presented in this paper where four point bending tests are analysed for temperatures ranging from 25 °C to 900 °C. For a ceramic mainly made of aluminium titanate, the evolution of an asymmetric constitutive law is identified with a strong link with microstructural observations using SEM images.  相似文献   
10.
Hooded rats with bilateral lesions of the anterior part of the hippocampal formation (HIP), anterior region of the posterior parietal cortex (APC), or posterior region of the posterior parietal cortex (PPC) were compared with controls for their exploration of 5 objects in an open field, habituation of locomotion and object investigation, and response to spatial and nonspatial change. First, all groups displayed habituation of both locomotor and exploratory activity. Second, controls selectively reexplored displaced objects, and APC-lesioned rats reexplored all objects, whereas PPC- and HIP-lesioned rats failed to react to the spatial change. Third, a novel object induced reexploration in all groups. Results are consistent with the roles of the HIP and PPC in spatial information processing. Moreover, the APC and PPC are involved in attentional effortful processing and visuospatial information processing necessary for spatial representation, respectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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