Human and simian T-cell leukemia viruses type 2 (HTLV-2 and STLV-2(pan-p)) transform T cells independently of Jak/STAT activation

Human T-lymphotropic virus type 1 (HTLV-1) and HTLV-2 differ in pathogenicity in vivo. HTLV-1 causes leukemia and neurologic and inflammatory diseases, whereas HTLV-2 is less clearly associated with human disease. Both retroviruses transform human T cells in vitro, and transformation by HTLV-1 was found to be associated with the constitutive activation of the Jak/STAT pathway. To assess whether HTLV-2 transformation may also result in constitutive activation of the Jak/STAT pathway, six interleukin-2-independent, HTLV-2-transformed T-cell lines were analyzed for the presence of activated Jak and STAT proteins by electrophoretic mobility shift assay. In addition, the phosphorylation status of Jak and STAT proteins was assessed directly by immunoprecipitation and immunoblotting with an antiphosphotyrosine antibody. Jak/STAT proteins were not found to be constitutively activated in any of the T-cell lines infected by the type 2 human and nonhuman primate viruses, suggesting that HTLV-2 and the cognate virus simian T-lymphotropic virus type 2 from Pan paniscus transform T cells in vitro by mechanisms at least partially different from those used by HTLV-1.     

Lexical effects in phonemic processing: Facilitatory or inhibitory?

This article addresses the questions of how and when lexical information influences phoneme identification in a series of phoneme-monitoring experiments in which conflicting predictions of autonomous and interactive models were evaluated. Strong facilitatory lexical effects (reflected by large differences in detection latencies to targets in words and matched nonwords) were found only when targets came after the uniqueness point of the target-bearing word. Furthermore, no evidence was obtained for lexically mediated inhibition on phoneme identification as predicted by the interactive activation model TRACE. These results taken together point to strong limitations in the way in which lexical information can affect the perception of unambiguous speech. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preserving architectural decisions through architectural patterns

Architectural decisions have emerged as a means to maintain the quality of the architecture during its evolution. One of the most important decisions made by architects are those about the design approach such as the use of patterns or styles in the architecture. The structural nature of this type of decisions give them the potential to be controlled systematically. In the literature, there are some works on the automation of architectural decision violation checking. In this paper we show that these works do not allow to detect all possible architectural decision violations. To solve this problem we propose an approach which: (i) describes architectural patterns that hold the architectural decision definition, (ii) integrates architectural decisions into an architectural model and, (iii) automates the architectural decision conformance checking. The approach is implemented using Eclipse modeling framework and its accompanying technologies. Starting from well-known architectural patterns, we show that we can formalize all those related to the structural aspect. Through two evaluations, we show that our approach can be adapted to different architecture paradigms and allows to detect more violations comparing to the existing approaches.     

Oral tissue response to ovine grafting biomaterial: Morphological and morphometric study using scanning electron and light microscopy tissue response to ovine grafting biomaterial

OBJECTIVE: To evaluate the oral tissue response to an experimental particle ovine biomaterial by scanning electron microscopy (SEM) and light microscopy (LM). MATERIAL AND METHODS: Forty‐eight rats had surgical periodontal defects treated with either blood clotting (control), bovine biomaterial? (B), or an experimental ovine biomaterial (O). Data from SEM analysis (defect exposure, root surface exposure, diameter of matrix fibers and bundles, and globuli areas; n = 5) were applied to Shapiro–Wilk, Kruskal–Wallis, and Dunn's test, whereas LM analysis (tissue cicatrization characteristics and diameter defect; n = 3) had data applied to two‐way analysis of variance. Animals were monitored for 1 and 3 weeks. RESULTS: By SEM, the O samples showed significant differences from B and C in the area of defect exposure (H_2,15 = 8.66; P < 0.05). In both periods, O and B samples showed similar results for matrix fiber diameters, differently than C samples (H_2,15 = 14.0; P < 0.05). All other SEM variables were considered equivalent among the groups (P > 0.05). Under LM, an acute and chronic granulomatous inflammation was seen in the presence of both biomaterials (B and O, 1 week); both the control and the ovine grafting samples showed mature bone in the repair site (3 weeks); the defect diameter showed similar values among groups, at both monitoring periods (F_2,12 = 1.0401; P > 0.05). CONCLUSION: The ovine particles of this study showed a favorable response to oral tissue repair, demonstrating to be a potential source for the development of bone grafting biomaterials. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc.     

Effects of composition of hardener on the curing and aging for an epoxy resin system

Different mixture ratios of Shell Epon 828 (based on diglycidyl ether of bisphenol A, DGEBA) and Shell EPI‐CURE 3046 (based on triethylenetetramine, TETA) were evaluated under different environments of isothermal curing at 80°C in DSC, room temperature curing in air, and aging in water at 45°C. The curing reactions were monitored using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and infrared spectroscopy (IR). It was shown that the initial curing rate increased with the amount of hardener. However, the epoxy groups in samples with excess hardener were prone to reaction with primary amines located at the ends of TETA molecules, resulting in a less dense epoxy network. During aging in water at 45°C, significant effects of water on the postcure and the increased water absorption with an increase of hardener amount were observed. The DMA results show that the samples with hardener around stoichiometric composition have the greatest storage modulus while curing in air environment. However, the samples with hardener much less than stoichiometric composition have greater storage modulus under aging in water at 45°C. in water at 45°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 580–588, 2006     

一种新型水产品冷藏运输车的可行性实验

首先对以液体CO2为冷源的这种新型水产品冷藏运输车的保温性能进行了实验,可以看出相同液体CO2及环境温度下,厢温维持在0℃的时间比维持在-18℃时延长了80%,每打开一次厢门,要用约20min的时间使厢温降到设定温度;接着对三种水产品冷藏运输车的运行经济性进行了比较,结果是液体CO2冷藏车的运输费用是机械冷藏车的70.4%,是冷板冷藏车运输费用的88.1%.因此,这种新型水产品冷藏运输车具有很好的开发价值与市场前景.     

The effects of discovery learning and expository instruction on the acquisition of definitional and intuitive knowledge

Abstract Types of learning with a strong emphasis on the responsibility of the learner (such as discovery learning) are gaining popularity over traditional forms of (expository) instruction. Discovery learning distinguishes itself by the central role of learning processes such as hypothesis generation (induction), experiment design, and data interpretation. Expository instruction pays more attention to directly ‘exposing’ definitions and equations to learners. In the current study, students worked with either a simulation (discovery learning) or a hypertext learning environment (expository instruction) with the same domain content. Each of the environments contained a large number of assignments. The study followed a pre‐test, post‐test design. To measure the knowledge acquired a definitional knowledge test, an intuitive knowledge test (where both correctness and speed of answering are aspects that are measured) and a test in which relations needed to be explained were administered. It was predicted that the hypertext group would outperform the simulation group on the definitional knowledge test and it was expected that the simulation group would perform better on the intuitive knowledge test. Results showed that both the interaction with the simulation and with the hypertext resulted in substantial learning gains. It was found that the hypertext group performed better on the definitional knowledge test. On the intuitive knowledge test the hypertext scored better than the simulation group on the correctness of the items but not on the time needed to answer items. On the explanation test there was no difference between the two groups. An analysis of interaction processes as recorded in the logfiles indicates that the differences between both environments in their actual usage were less distinctive than expected. In the simulation group many students followed the assignments given and did not engage in self‐guided discovery. Since the assignments were rather directive, this resulted in ‘discovery behaviour’ that focused on generating outcomes; outcomes that were also, and more directly presented in the hypertext environment. For research and practice, this implies that simulations are to be considered only when clear benefits of discovery are expected, and only with complex domains, sufficient learning time and freedom for students in the assignments to engage in discovery.     

A method to analyse neighbourhood characteristics of land use patterns

Neighbourhood interactions between land use types are often included in the spatially explicit analysis of land use change. Especially in the context of urban growth, neighbourhood interactions are often addressed both in theories for urban development and in dynamic models of (urban) land use change. Neighbourhood interactions are one of the main driving factors in a large group of land use change models based on cellular automata (CA).This paper introduces a method to analyse the neighbourhood characteristics of land use. For every location in a rectangular grid the enrichment of the neighbourhood by specific land use types is studied. An application of the method for the Netherlands indicates that different land use types have clearly distinct neighbourhood characteristics. Land use conversions can be explained, for a large part, by the occurrence of land uses in the neighbourhood.The neighbourhood characterization introduced in this paper can help to further unravel the processes of land use change allocation and assist in the definition of transition rules for cellular automata and other land use change models.     

Optimizing the end-point state-weighting matrix in model-based predictive control

In this paper a linear model-based predictive control (MPC) algorithm is presented, for which nominal closed-loop stability is guaranteed. The input is obtained by minimizing a quadratic performance index over a finite horizon plus an end-point state (EPS) penalty, subject to input, state and output constraints. Under certain conditions, the weighting matrix in the EPS penalty enables one to specify an invariant ellipsoid in which the input, state and output constraints are satisfied. In existing MPC algorithms this weighting matrix is calculated off-line. The main contribution of this paper is to incorporate the calculation of the EPS-weighting matrix into the on-line optimization problem of the controller. The main advantage of this approach is that a natural and automatic trade-off between feasibility and optimality is obtained. This is demonstrated in a simulation example.