散落在云南的日子

阳光下,圣洁的雪峰屹立着古老的沧桑,现代的神秘,让我一如既往地憧憬那天边的金色殿堂。大假。约驴友共赴春城。除了路途颠簸的两整天,剩余的八个日子有如繁星,轻轻地散落在云南的各个角落,以至长时间里几度提笔,也不曾找到自己被     

Biased processing of emotional information in girls at risk for depression.

Researchers have documented that children of depressed mothers are at elevated risk for developing a depressive disorder themselves. There is currently little understanding, however, of what factors place these children at elevated risk. In the present study, the authors investigated whether never-disordered daughters whose mothers have experienced recurrent episodes of depression during their daughters' lifetime are characterized by biased processing of emotional information. Following a negative mood induction, participants completed an emotional-faces dot-probe task. Daughters at elevated risk for depression, but not control daughters of never-disordered mothers, selectively attended to negative facial expressions. In contrast, only control daughters selectively attended to positive facial expressions. These results provide support for cognitive vulnerability models of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Configuration Complexity Model and Its Application to a Change Management System

The complexity of configuring computing systems is a major impediment to the adoption of new information technology (IT) products and greatly increases the cost of IT services. This paper develops a model of configuration complexity and demonstrates its value for a change management system. The model represents systems as a set of nested containers with configuration controls. From this representation, we derive various metrics that indicate configuration complexity, including execution complexity, parameter complexity, and memory complexity. We apply this model to a J2EE-based enterprise application and its associated middleware stack to assess the complexity of the manual configuration process for this application. We then show how an automated change management system can greatly reduce configuration complexity.     

Quantatitive assessment of enzyme immobilization capacity in porous silicon

Immobilized enzyme systems are important in a broad range of applications, from biological sensing to the industrial-scale biocatalytic synthesis of chiral products. We demonstrate the ability to systematically vary and quantitatively assess the immobilization capacity of porous silicon thin films for the enzyme glutathione-S-transferase in a manner predicted by a simple geometric model of the porous silicon matrix. We find that the immobilization capacity quantatitively correlates with systematic changes in the device thickness. These results are significant since, despite the wide range over which porous silicon morphology and surface area can be varied, few attempts have been made to systematically characterize surface binding capacity. Our findings suggest that porous silicon can be an ideal matrix, where immobilization of a predictable quantity of biological material is desired.     

The Emotional Wardrobe

Since the industrial revolution, fashion and technology have been linked through the textile and manufacturing industries, a relationship that has propelled technical innovation and aesthetic and social change. Today, a new alliance is emerging through the integration of electronic technology and smart materials on the body. This study addresses the integration of technology with clothing from a fashion perspective, and examines its expressive and interactive potential. It proposes the concept of The Emotional Wardrobe: clothing that represents and stimulates emotional response through the interface of technology. It asks if fashion can offer a more personal and provocative definition of self, which actively involves the wearer in a mutable aesthetic identity. A multi-disciplinary framework combines fashion, material science and the real-time, affective computing platform, called AffectiveWare. By merging technology and fashion, The Emotional Wardrobe becomes a poetic interface, shifting emphasis from human–computer interaction to computer-aided, human–human communication.     

Identification of a neurosteroid binding site contained within the GluR2-S1S2 domain

Glutamate receptors play a major role in neural cell plasticity, growth, and maturation. The degree to which ionotropic glutamate receptors (iGluR) conduct current is dependent on binding of extracellular ligands, of which glutamate is the native agonist. Although the glutamate binding site of the GluR2 class of amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) iGluR has been structurally characterized, the allosteric sites attributed to neurosteroid binding have yet to be localized. Here, using intrinsic tryptophan fluorescence spectroscopy, we show that the extracellular glutamate binding core of the GluR2 class of AMPA receptors also binds to two neurosteroids, pregnenolone sulfate (PS) and 3α-hydroxy-5β-pregnan-20-one sulfate, both of which negatively modulate its activity. Interest in these sulfated neurosteroids stems from their differential modulation of other members of the iGluR family and their potential use as endogeneous agents for stroke therapy. In particular, whereas PS inhibits AMPA and other non-N-methyl-d-aspartate (NMDA) family members, it activates the NMDA receptor. In addition to providing evidence for binding of these neurosteroids to the glutamate binding core of the GluR2 class of AMPA receptors, our data suggests that both neurosteroids bind in a similar manner, consistent with their modulation of activity of this class of iGluR. Interestingly, the conformational change induced upon binding of these neurosteroids is distinct from that induced upon glutamate binding.     

Adhesive forces significantly affect elastic modulus determination of soft polymeric materials in nanoindentation

The present study investigated the effects of adhesion on the elastic modulus determined from nanoindentation curves for soft polydimethylsiloxane (PDMS) elastomers with five different crosslink concentrations. Indentation load-displacement curves were obtained for samples of all concentrations at four different peak loads. All load-displacement curves were nearly linear, resulting in load independent contact stiffnesses (p < 0.003) for the range of loads tested. As a result, elastic modulus calculated from nanoindentation curves with the Hertz contact model exhibited significant differences (p < 0.004) both at different peak loads for a single PDMS concentration and between different PDMS concentrations at a single peak load (p < 0.001). The differences for different peak loads were attributed to the presence of substantial adhesive forces at the tip-sample interface. By taking these adhesive interactions into account with the Johnson, Kendall, Roberts (JKR) contact model, the differences in elastic modulus at different peak loads could be reconciled. Significant differences (p < 0.001) in moduli between different PDMS concentrations were still present. The results highlight the importance of considering adhesive forces in nanoindentation analyses of low modulus polymeric materials.     

Label-free quantitative detection of protein using macroporous silicon photonic bandgap biosensors

A label-free biosensor was demonstrated using macroporous silicon (pore size >100 nm) one-dimensional photonic band gap structures that are very sensitive to refractive index changes. In this study, we employed Tir-IBD (translocated Intimin receptor-Intimin binding domain) and Intimin-ECD (extracellular domain of Intimin) as the probe and target, respectively. These two recombinant proteins comprise the extracellular domains of two key proteins responsible for the pathogenicity of enteropathogenic Escherichia coli (EPEC). The optical response of the sensor was characterized so that the capture of Intimin-ECD could be quantitatively determined. Our result shows that the concentration sensitivity limit of the sensor is currently 4 microM of Intimin-ECD. This corresponds to a detection limit of approximately 130 fmol of Intimin-ECD. We have also investigated the dependence of the sensor performance on the Tir-IBD probe molecule concentration and the effect of immobilization on the Tir-IBD/Intimin-ECD equilibrium dissociation constant. A calibration curve generated from purified Intimin-ECD solutions was used to quantify the concentration of Intimin-ECD in an E. coli BL21 bacterial cell lysate, and results were validated using gel electrophoresis. This work demonstrates for the first time that a macroporous silicon microcavity sensor can be used to selectively and quantitatively detect a specific target protein with micromolar dissociation constant (Kd) in a milieu of bacterial proteins with minimal sample preparation.     

Attachment theory as an organizing framework: A view from different levels of analysis.

In recognition of the broad influence of attachment theory, the articles in this issue cut across diverse areas of psychology and multiple levels of analysis. T. R. Insel (2000) focuses on the molecular level, discussing the complex link between neurobiology and attachment behavior in nonhuman animals. The three articles by J. Cassidy (2000), R. C. Fraley and P. R. Shaver (2000), and P. R. Pietromonaco and L. Feldman Barrett (2000) present midlevel analyses, incorporating ideas about the links between mental representations and relationship thoughts, feelings, and behavior. C. Hazan and L. A Diamond (2000) take a macro approach by applying a broad evolutionary perspective to understand the basis for attachment in adult pair bonds. The discussion focuses on unifying themes, including the interplay between attachment, caregiving, and sexual behavior; attachment functions in adult relationships; evolutionary processes; the operation of internal working models; and continuity in attachment across the life span. (PsycINFO Database Record (c) 2010 APA, all rights reserved)