Identifying patterns of informant discrepancy and trajectories of youth depressive symptoms through a latent variable approach

The aim of this study was to identify classes of children at the outset of school transitions with different patterns of informant discrepancy with respect to depressive symptoms. A latent class analysis was conducted with a longitudinal sample of 456 predominantly low-income African American children. Results identified multiple classes of children differentiated mostly by symptom severity. Regression analysis identified significant differences between classes and predictors of depressive symptoms including student self-esteem and perceived parental monitoring, parent rated behavioral indicators such as peer rejection and teacher rated need for counseling services. Although there were relatively consistent reports among informants, latent class regressions still show meaningful differences between informants on variables that may provide contextual information about depressive symptoms. A latent transition analysis found that class membership was relatively stable between 6th and 9th grade time points and the majority of transitions were made by students transitioning into lower depression-risk classes. These findings serve an important role in continued validation of the diverging operations approach as a useful framework for understanding informant discrepancies.Includes bibliographical references

Evaluation of an interpretation bias modification program targeting internalizing symptoms in secondary school students

The current study evaluated an intervention that supports secondary school students with internalizing symptoms through a computerized Interpretation Bias Modification program. The program is defined by multiple training sessions that reinforce the adoption of more positive interpretations of ambiguous social scenarios. The program's goal is to increase the accuracy and speed with which students can judge the threat-based nature of events they are likely to encounter in their day-to-day lives. As students' progress through the training program, measurements were made regarding their 'online' and 'offline' processing biases and the association to cognitive and behavioral internalizing symptoms known to maintain depressive and anxious conditions. The randomized waitlist control trial design was conducted with students ages 11-18, drawn from school and community samples. The researchers compared internalizing behavior of the treatment group (N = 56) to the participant outcomes in the waitlist control group (N = 45). The variables of interest were measures of anxiety, depression, and patterns of negative thought that embody both conditions. Variables related to Primary findings from t-tests, ANCOVA, growth curve analysis, and linear mixed-effects model regressions indicated significant differences between the training conditions and within the training condition as a function of training. Researchers identified a medium effects size on reductions in depressive symptoms within the treatment group. There were positive findings regarding the acceptability of the interpretation bias training intervention. Limitations and future directions for this area of research are discussed.Includes bibliographical references

A Model of Function-Based Representations

The need to model and to reason about design alternatives throughout the design process demands robust representation schemes of function, behavior, and structure. Function describes the physical effect imposed on an energy or material flow by a design entity without regard for the working principles or physical solutions used to accomplish this effect. Behaviors are the physical events associated with a physical artifact (or hypothesized concept) over time (or simulated time) as perceived by an observer. Structure, the most tangible concept, partitions an artifact into meaningful constituents such as features, Wirk elements, and interfaces in addition to the widely used assemblies and components. The focus of this work is on defining a model for function-based representations that can be used across various design methodologies and for a variety of design tasks throughout all stages of the design process. In particular, the mapping between function and structure is explored and, to a lesser extent, its impact on behavior is noted. Clearly, the issues of a function-based representation\u27s composition and mappings directly impact certain computational synthesis methods that rely on (digitally) archived product design knowledge. Moreover, functions have already been related to not only form, but also information of user actions, performance parameters in the form of equations, and failure mode data. It is essential to understand the composition and mappings of functions and their relation to design activities because this information is part of the foundation for function-based methods, and consequently dictates the performance of those methods. Toward this end, the important findings of this work include a formalism for two aspects of function-based representations (composition and mappings), the supported design activities of the model for function-based representations, and examples of how computational design methods benefit from this formalism

A Qualitative Modeling Method for Platform Design

The development of a collection of related products sharing a common platform represents an important approach in modern product design. an ongoing problem is the application of design methods toward a limited set of evolving product data and archived design knowledge to search and explore alternative platform options. with the goal of maximizing the reuse of end item artifacts and supply chain elements, we propose a design modeling method using basic qualitative relationships among relevant performance, design, and noise parameters in the system of interest. by using qualitative models related to multiple levels of design data, the method provides a single high level graphical representation among design data including archived knowledge in a design repository. © 2005 IEEE

A GROUP TECHNOLOGY BASED REPRESENTATION FOR PRODUCT PORTFOLIOS

ABSTRACT Repository based applications for portfolio design offer the potential for leveraging archived design data with computational searches. Toward the development of such search tools, we present a representation for product portfolios that is an extension of an existing Group Technology (GT) coding scheme. Relevance to portfolio design is treated with a case study example of a hand held grinder design. Results of this work provide a numerical coding representation that captures function, form, material and manufacturing data for systems. This extends the current GT line work by combining these four types of design data and clarifying the use of the functional basis in a GT code. The results serve as a useful starting point for the development of portfolio design algorithms, such as genetic algorithms, that account for this combination of design information

Exhaled Aerosol Transmission of Pandemic and Seasonal H1N1 Influenza Viruses in the Ferret

Person-to-person transmission of influenza viruses occurs by contact (direct and fomites) and non-contact (droplet and small particle aerosol) routes, but the quantitative dynamics and relative contributions of these routes are incompletely understood. The transmissibility of influenza strains estimated from secondary attack rates in closed human populations is confounded by large variations in population susceptibilities. An experimental method to phenotype strains for transmissibility in an animal model could provide relative efficiencies of transmission. We developed an experimental method to detect exhaled viral aerosol transmission between unanesthetized infected and susceptible ferrets, measured aerosol particle size and number, and quantified the viral genomic RNA in the exhaled aerosol. During brief 3-hour exposures to exhaled viral aerosols in airflow-controlled chambers, three strains of pandemic 2009 H1N1 strains were frequently transmitted to susceptible ferrets. In contrast one seasonal H1N1 strain was not transmitted in spite of higher levels of viral RNA in the exhaled aerosol. Among three pandemic strains, the two strains causing weight loss and illness in the intranasally infected ‘donor’ ferrets were transmitted less efficiently from the donor than the strain causing no detectable illness, suggesting that the mucosal inflammatory response may attenuate viable exhaled virus. Although exhaled viral RNA remained constant, transmission efficiency diminished from day 1 to day 5 after donor infection. Thus, aerosol transmission between ferrets may be dependent on at least four characteristics of virus-host relationships including the level of exhaled virus, infectious particle size, mucosal inflammation, and viral replication efficiency in susceptible mucosa

Labor And The Politics Of Structural Adjustment In Australia And Indonesia

The labour forces of Australia and Indonesia are compared for the period from the late 1960s to the 1990s. The position of labour in a global economy is also considered. It is determined that the outlook for organised labour is bleak, however its position is also contingent upon national circumstance

Designing product architecture: a systematic method

textArchitecture design, also thought of more loosely as layout design within the context of conceptual design, is one stage of the mechanical design process that significantly impacts product performance in terms of manufacturing, assembly, modularity, product family variety, maintenance, etc. This design step is special because it marks an occasion when many effects, including geometric concerns, come into play simultaneously on a large scale. The purpose of this research is to investigate the architecture design phase and develop a new design method as there is currently no consensus regarding a best strategy for dealing with architecture design. The resulting method is based primarily on the development of a formal representation and a set of guidelines derived from an empirical product study. Each of these three main deliverables are assessed and validated as part of their development. Based on the concept of a mental model, a representation is developed which consists of a lexicon and a six element notation known as the architecture workframe. Terms of the lexicon provide a well-defined means to describe various aspects of architecture while the notation instantiates these terms in a reasonable format in order to facilitate effective manipulation of the architecture. This representation allows the designer to incrementally proceed from initial constraints to a fully described layout at the conceptual level. The representation directly supports design for modularity and design for flexibility. Effectiveness of the representation is confirmed through an experimental comparison of this technique with an analogous conventional method. Results are promising in terms of the quantity, quality, and efficiency of design solution. In working toward the second deliverable, an empirical study of thirty product evolutions is performed and ten guidelines are extracted through a process of making observations, hypothesizing guidelines, and refining a set of guidelines. Validation of these guidelines is performed using a second sample set of existing products that are representative of the larger population of products. Finally, a cohesive method is proposed to encapsulate the representation and guidelines into a design strategy. The method is assessed with respect to method constituents and the expected bounds of performance of those constituents.Mechanical Engineerin