Photoactivatable GFP tagging cassettes for protein-tracking studies in the budding yeast Saccharomyces cerevisiae

Yeast cell biologists use a variety of fluorescent protein tags for determining protein localization and for measuring protein dynamics using fluorescence recovery after photobleaching (FRAP). Although many modern fluorescent proteins, such as those with photoactivatable and photoconvertible characteristics, have been developed, none has been exploited for studies in budding yeast. We describe here the construction of yeast-tagging vectors containing photoactivatable green fluorescent protein (PA-GFP) for analysis of protein behaviour. We tagged two yeast proteins, Erg6p and Num1p, with PA-GFP and demonstrated specific photoactivation of the fusion proteins in live cells. Fluorescence intensity measurements showed that a short 5 s exposure to 413 nm light is sufficient to produce the maximum level of activated GFP fluorescence. Local photoactivation of cortical Num1p-PA-GFP showed movement of the marked proteins, providing new insights into the behaviour of Num1p at the cell cortex. Since photoactivation can be achieved using standard mercury arc illumination, the PA-GFP tag represents a convenient and economical way to determine protein dynamics in the cell. Thus, the tagging modules should facilitate protein-tracking studies in a wide variety of cell biological processes in yeast.     

Mediated Electrochemistry to Mimic Biology's Oxidative Assembly of Functional Matrices

Biology uses diffusible oxidants to perform functions that range from signaling to matrix assembly, and these oxidation chemistries offer surprising selectivities. Here, it is reported that mediated electrochemistry can access the richness of such oxidation chemistries. Specifically, electrode‐imposed voltage inputs are used to locally generate oxidized mediators that can diffuse into polymer solutions and induce the formation of covalent bonds for the deposition and functionalization of hydrogels at the electrode surface. Depending on the mediator's redox potential (E⁰), it is possible to “gate” the voltage inputs to target specific residues (e.g., thiols or amines) and oxidation chemistries. Further, mediators of varying E⁰ offer different reactivities and thus allow control of reaction‐diffusion rates to modulate the hydrogel's crosslink density and mechanical properties. Importantly, this mediated oxidation can be performed under physiologically relevant conditions to preserve labile biological functionalities (e.g., cell viability and protein function). Finally, it is demonstrated that protein fusion tags can be engineered to have “targetable” amino acid residues that enable protein function to be oxidatively conjugated to electrodeposited hydrogels. In summary, mediated electrochemistry can engage orthogonal oxidation chemistries to create functionalized matrices and thus mediated electrochemistry should add important capabilities to the electrofabrication toolbox.     

Performance analysis and comparison of optical signal processing beamforming networks: a survey

Photonic Network Communications - Forthcoming wireless systems are developed to support greater data rate and extra coverage area. This can be achieved with the help of multiple input multiple...     

Tensile properties of latex paint films with TiO2 pigment

The tensile properties of latex paint films containing TiO₂ pigment were studied with respect to temperature, strain-rate and moisture content. The purpose of performing these experiments was to assist museums in defining safe conditions for modern paintings held in collections. The glass transition temperature of latex paint binders is in close proximity to ambient temperature, resulting in high strain-rate dependence in typical exposure environments. Time dependence of modulus and failure strain is discussed in the context of time–temperature superposition, which was used to extend the experimental time scale. Nonlinear viscoelastic material models are also presented, which incorporate a Prony series with the Ogden or Neo-Hookean hyperelastic function for different TiO₂ concentrations.     

Unique and common mechanisms of change across cognitive and dynamic psychotherapies.

The goal of this article was to examine theoretically important mechanisms of change in psychotherapy outcome across different types of treatment. Specifically, the role of gains in self-understanding, acquisition of compensatory skills, and improvements in views of the self were examined. A pooled study database collected at the University of Pennsylvania Center for Psychotherapy Research, which includes studies conducted from 1995 to 2002 evaluating the efficacy of cognitive and psychodynamic therapies for a variety of disorders, was used. Patient samples included major depressive disorder, generalized anxiety disorder, panic disorder, borderline personality disorder, and adolescent anxiety disorders. A common assessment battery of mechanism and outcome measures was given at treatment intake, termination, and 6-month follow-up for all 184 patients. Improvements in self-understanding, compensatory skills, and views of the self were all associated with symptom change across the diverse psychotherapies. Changes in self-understanding and compensatory skills across treatment were predictive of follow-up symptom course. Changes in self-understanding demonstrated specificity of change to dynamic psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The use of ICT in primary schools within emerging communities of implementation

To illustrate the conditions under which successful innovation adoption takes place, this paper focuses on the implementation of information and communication technologies (ICT) through emerging communities in schools. Two types of such communities are described in terms of the degree of participation in the implementation: school-wide communities and enclaves. The article describes implementation practices in four primary schools with reported high ICT use, selected as case-studies. Four criteria, reflecting the domain, personnel relationships, policy and implementation goals and strategies, as well as staff consistency, are employed to outline the existence and types of communities of implementation within these schools. Findings indicate that, although both school-wide communities and enclaves are present in successful schools, enclaves – compared to school-wide communities – are related to lower levels of implementation. Based on these findings the authors discuss policy directions towards the development of school-wide communities as a purposeful implementation strategy to help transition ICT institutionalization from the initiation to the habitualization stage.     

A decision support system for coating selection based on fuzzy logic and multi-criteria decision making

Wear and corrosion are the most important factors that the surface of the engineering parts must confront. The need for protection and improvement of the mechanical characteristics of the surface of engineering parts can be to some extent satisfied by coatings. Coatings are considered as an excellent solution when resistance to corrosion, oxidation or low friction is demanded, but due the complexity of selecting the appropriate one, engineers often avoid them. The need for simultaneous consideration of qualitative and quantitative properties, render the use of classic material selection theories inadequate. An expert system for coating selection is presented in this paper, which can handle both qualitative and quantitative variables. The mathematical model used combines the multi-criteria decision making theories (MCDM) together with the fuzzy sets theory. The “Max-Min set” method is applied to calculate the ordering value of the alternatives while the TOPSIS method is used to rank them. A numerical example is provided to illustrate the method. Finally, the process presented can be easily computerized, to create the relative software.     

可改进太阳能电池的新型电特性

由铋、铁和氧组成的晶体能够实现可逆的二极管 美国Rutgers大学的一组物理学家发现了一种材料所具有的特殊电特性,能够提升太阳能电池效率并改善计算机芯片设计.这种由铋、铁和氧组成的晶体能够实现可逆的二极管,这种二极管在光照条件下就能产生电流.传统的半导体二极管是不可逆的,其电流方向在制造时就已经确定下来了.