Roll manufacturing of flexible microfluidic devices in thin PMMA and COC foils by embossing and lamination

Microfluidics on foil is gaining momentum due to a number of advantages of employing thin films combined with the capability of cost-effective high-volume manufacturing of devices. In this work, ultra-thin, flexible Y-microreactors with microchannels of 100 μm width and 30 μm depth were fabricated in thermoplastic polymer foils. The fluidic pattern was hot roll embossed in 125 μm thick poly-methyl-methacrylate (PMMA) and 130 μm thick cyclic-olefin-copolymer (COC) films using a dry-etched microstructured silicon wafer as a flat embossing tool in a laminator. The sealing of the channels was performed with two different techniques, one based on lamination of SU8 dry film resist (DFR) and the other one based on spin-coated poly-dimethylsiloxane (PDMS). Testing of the interconnected microreactor was carried out using two dye colorant solutions to demonstrate mixing.     

Social desirability and the randomized response technique.

The randomized response technique (RRT) is designed to increase respondents' willingness to answer truthfully questions of a sensitive or socially undesirable nature. This study tested the hypothesis that the difference between the proportion of "yes" responses obtained under self-administered direct questioning and the proportion of "yes" responses obtained under an RRT procedure would be related to the social desirability of a "yes" response to the question. The hypothesis was confirmed by data from 404 undergraduates; the RRT may provide more valid responses to items of a socially desirable and undesirable nature. The RRT deserves more attention because it can circumvent biases due to untruthful responding, demand characteristics, and evaluation apprehension as well as assure the confidentiality of the data. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The beta exponential distribution

The exponential distribution is perhaps the most widely applied statistical distribution for problems in reliability. In this note, we introduce a generalization—referred to as the beta exponential distribution—generated from the logit of a beta random variable. We provide a comprehensive treatment of the mathematical properties of the beta exponential distribution. We derive expressions for the moment generating function, characteristic function, the first four moments, variance, skewness, kurtosis, mean deviation about the mean, mean deviation about the median, Rényi entropy, Shannon entropy, the distribution of sums and ratios, and the asymptotic distribution of the extreme order statistics. We also discuss simulation issues, estimation by the methods of moments and maximum likelihood and provide an expression for the Fisher information matrix. We hope that this generalization will attract wider applicability in reliability.     

Diagnostic categories or dimensions? A question for the Diagnostic and statistical manual of mental disorders--fifth edition.

The question of whether mental disorders are discrete clinical conditions or arbitrary distinctions along dimensions of functioning is a long-standing issue, but its importance is escalating with the growing recognition of the frustrations and limitations engendered by the categorical model. The authors provide an overview of some of the dilemmas of the categorical model, followed by a discussion of research that addresses whether mental disorders are accurately or optimally classified categorically or dimensionally. The authors' intention is to document the importance of this issue and to suggest that future editions of the Diagnostic and Statistical Manual of Mental Disorders give more recognition to dimensional models of classification. They conclude with a dimensional mental disorder classification that they suggest provides a useful model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Practice Makes Progress? Homework Assignments and Outcome in Treatment of Cocaine Dependence.

The relationship between treatment outcome and the extent to which participants completed homework assignments was evaluated among 60 cocaine-dependent individuals assigned to cognitive-behavioral therapy (CBT). Homework was assigned in 72% of all sessions and initiated by participants in 48% of the sessions in which it was assigned. Completion of homework was unrelated to participants' baseline characteristics and several indicators of treatment compliance. Participants who completed more homework assignments demonstrated significantly greater increases in the quantity and quality of their coping skills and used significantly less cocaine during treatment and through a 1-year follow-up. These data suggest that the extent to which participants are willing to complete extrasession assignments may be an important mediator of response to CBT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence-based parent and family interventions in school psychology: Overview and procedures.

This special issue, entitled "Evidence-Based Parent and Family Interventions in School Psychology," examines the data that support the use of interventions as methods for changing children's school-related behavior and learning problems. Taken together, the articles reflect the work of the Parent and Family Intervention domain of the Evidence-Based Interventions in School Psychology Task Force. Across the articles in this special issue, the categories of coding criteria in the Manual were used to organize the presentation of results. Six review articles on the evidence base for parent and family intervention appear next; these are followed by commentary from distinguished scholars and a brief reflective comment from the special issue editors. Parent intervention is the exclusive focus of the reviews of parent education and parent consultation. Two reviews focus on the home-school relationship including the articles on parent involvement and home-school collaboration. Two reviews include both parent and family treatments: early childhood family-focused interventions and parent training and family systems interventions. Commentary was sought from the current co-chairs of the Task Force, an expert in evidence-based practice in child clinical psychology, a researcher in family-school linkages and parent consultation, and a methodologist. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Attention: Reaction Time and Accuracy Reveal Different Mechanisms.

The authors propose that there are 2 different mechanisms whereby spatial cues capture attention. The voluntary mechanism is the strategic allocation of perceptual resources to the location most likely to contain the target. The involuntary mechanism is a reflexive orienting response that occurs even when the spatial cue does not indicate the probable target location. Voluntary attention enhances the perceptual representation of the stimulus in the cued location relative to other locations. Hence, voluntary attention affects performance in experiments designed around both accuracy and reaction time. Involuntary attention affects a decision as to which location should be responded to. Because involuntary attention does not change the perceptual representation, it affects performance in reaction time experiments but not accuracy experiments. The authors obtained this pattern of results in 4 different versions of the spatial cuing paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparative study of some concurrency control algorithms for cluster-based communication networks

This paper presents a comparative study of some concurrency control algorithms for distributed databases of computer clusters which emphasize high availability and high performance requirements. For this purpose, we have analyzed some concurrency control algorithms which are used in commercial DBMSs, such as the pessimistic locking algorithm as it verifies transaction conflicts early in their execution phase, and the optimistic algorithm which investigates the presence of conflicts after the execution phase. A new algorithm is proposed and implemented by a simulation program. The three algorithms were tested using different configurations. Simulation results showed that the locking algorithm performed better than the optimistic method in presence of conflicts between transactions, while the optimistic algorithm provided better results in the absence of conflicts. Furthermore, in a distributed database with a certain probability of conflicts, the locking algorithm can be used to guarantee strong consistency and an acceptable level of performance. However, if this probability is negligible, the system performance can be improved by using the optimistic algorithm. The proposed algorithm offers improved performance in numerous cases. As a result, it can be used in a distributed database to guarantee a satisfactory level of performance in the presence of conflicts.     

Maternal Regulation of Infant Reactivity From 2 to 6 Months.

Previous research has investigated the effect of maternal soothing behaviors on reducing infant reactivity but not the differential effects of specific maternal behaviors on infant stress responses. The present study investigated maternal regulation of 2- and 6-month-olds' responses to an inoculation and found a significant decline with age in both the intensity and duration of infants' crying. Maternal affection and touching decreased from 2 to 6 months, whereas maternal vocalizing and distraction behaviors increased. At both ages, the combination of maternal holding/rocking and vocalizing was associated with decreases in all levels of infant reactivity. Neither strategy alone, however, was found to be effective. Feeding/ pacifying behaviors were effective only when initial distress was at a low or moderate level, which suggests that the effectiveness of maternal regulatory behaviors may depend on the intensity of infants' crying. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object-Oriented Optimization Approach Using Genetic Algorithms for Lattice Towers

A new approach is presented for the optimization of steel lattice towers by combining genetic algorithms and an object-oriented approach. The purpose of this approach is to eliminate the difficulties in the handling of large size problems such as lattice towers. Improved search and rapid convergence are obtained by considering the lattice tower as a set of small objects and combining these objects into a system. This is possible with serial cantilever structures such as lattice towers. A tower consists of panel objects, which can be classified as separate objects, as they possess an independent property as well as inherent properties. This can considerably reduce the design space of the problem and enhance the result. An optimization approach for the steel lattice tower problem using objects and genetic algorithms is presented here. The paper also describes the algorithm with practical design considerations used for this approach. To demonstrate the approach, a typical tower configuration with practical constraints has been considered for discrete optimization with the new approach and compared with the results of a normal approach in which the full tower is considered.