55 research outputs found

    Calculation of the relative metastabilities of proteins in subcellular compartments of Saccharomyces cerevisiae

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    [abridged] Background: The distribution of chemical species in an open system at metastable equilibrium can be expressed as a function of environmental variables which can include temperature, oxidation-reduction potential and others. Calculations of metastable equilibrium for various model systems were used to characterize chemical transformations among proteins and groups of proteins found in different compartments of yeast cells. Results: With increasing oxygen fugacity, the relative metastability fields of model proteins for major subcellular compartments go as mitochondrion, endoplasmic reticulum, cytoplasm, nucleus. In a metastable equilibrium setting at relatively high oxygen fugacity, proteins making up actin are predominant, but those constituting the microtubule occur with a low chemical activity. A reaction sequence involving the microtubule and spindle pole proteins was predicted by combining the known intercompartmental interactions with a hypothetical program of oxygen fugacity changes in the local environment. In further calculations, the most-abundant proteins within compartments generally occur in relative abundances that only weakly correspond to a metastable equilibrium distribution. However, physiological populations of proteins that form complexes often show an overall positive or negative correlation with the relative abundances of proteins in metastable assemblages. Conclusions: This study explored the outlines of a thermodynamic description of chemical transformations among interacting proteins in yeast cells. The results suggest that these methods can be used to measure the degree of departure of a natural biochemical process or population from a local minimum in Gibbs energy.Comment: 32 pages, 7 figures; supporting information is available at http://www.chnosz.net/yeas

    Cognitive and Psychological Reactions of the General Population Three Months After the 2011 Tohoku Earthquake and Tsunami

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    BACKGROUND: The largest earthquake on record in Japan (magnitude 9.0) occurred on March 11, 2011, and the subsequent tsunami devastated the Pacific coast of Northern Japan. These further triggered the Fukushima I nuclear power plant accidents. Such a hugely complex disaster inevitably has negative psychological effects on general populations as well as on the direct victims. While previous disaster studies enrolled descriptive approaches focusing on direct victims, the structure of the psychological adjustment process of people from the general population has remained uncertain. The current study attempted to establish a path model that sufficiently reflects the early psychological adaptation process of the general population to large-scale natural disasters. METHODS AND FINDINGS: Participants from the primary disaster area (n = 1083) and other areas (n = 2372) voluntarily participated in an online questionnaire study. By constructing path models using a structural equation model procedure (SEM), we examined the structural relationship among psychological constructs known related to disasters. As post-traumatic stress symptoms (PTS) were significantly more present in people in the primarily affected area than in those in secondary- or non-affected areas, the path models were constructed for the primary victims. The parsimoniously depicted model with the best fit was achieved for the psychological-adjustment centered model with quality of life (QoL) as a final outcome. CONCLUSION: The paths to QoL via negative routes (from negative cognitive appraisal, PTS, and general stress) were dominant, suggesting the importance of clinical intervention for reducing negative cognitive appraisal, and for caring for general stress and PTS to maintain QoL at an early stage of psychological adaptation to a disaster. The model also depicted the presence of a positive route where positive cognitive appraisal facilitates post-traumatic growth (PTG) to achieve a higher QoL, suggesting the potential importance of positive psychological preventive care for unexpected natural disasters

    Change & Maintaining Change in School Cafeterias: Economic and Behavioral-Economic Approaches to Increasing Fruit and Vegetable Consumption

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    Developing a daily habit of consuming fruits and vegetables (FV) in children is an important public-health goal. Eating habits acquired in childhood are predictive of adolescent and adult dietary patterns. Thus, healthy eating patterns developed early in life can protect the individual against a number of costly health deficits and may reduce the prevalence of obesity. At present, children in the United States (US) under-consume FV despite having access to them through the National School Lunch Program. Because access is an obstacle to developing healthy eating habits, particularly in low-income households, targeting children’s FV consumption in schools has the advantage of near-universal FV availability among more than 30 million US children. This chapter reviews economic and behavioral-economic approaches to increasing FV consumption in schools. Inclusion criteria include objective measurement of FV consumption (e.g., plate waste measures) and minimal demand characteristics. Simple but effective interventions include (a) increasing the variety of vegetables served, (b) serving sliced instead of whole fruits, (c) scheduling lunch after recess, and (d) giving children at least 25 minutes to eat. Improving the taste of FV and short-term incentivizing consumption of gradually increasing amounts can produce large increases in consumption of these foods. Low-cost game-based incentive program may increase the practicality of the latter strategy

    Uthando Lwethu ('our love'): a protocol for a couples-based intervention to increase testing for HIV: a randomized controlled trial in rural KwaZulu-Natal, South Africa.

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    BACKGROUND: Couples-based HIV counseling and testing (CHCT) is a proven strategy to reduce the risk of HIV transmission between partners, but uptake of CHCT is low. We describe the study design of a randomized controlled trial (RCT) aimed to increase participation in CHCT and reduce sexual risk behavior for HIV among heterosexual couples in rural KwaZulu-Natal, South Africa. We hypothesize that the rate of participation in CHCT will be higher and sexual risk behavior will be lower in the intervention group as compared to the control. METHODS/DESIGN: Heterosexual couples (N=350 couples, 700 individuals) are being recruited to participate in a randomized trial of a couples-based intervention comprising two group sessions (one mixed gender, one single gender) and four couples' counseling sessions. Couples must have been in a relationship together for at least 6 months. Quantitative assessments are conducted via mobile phones by gender-matched interviewers at baseline, 3, 6, and 9 months post-randomization. Intervention content is aimed to improve relationship dynamics, and includes communication skills and setting goals regarding CHCT. DISCUSSION: The Uthando Lwethu ('our love') intervention is the first couples-based intervention to have CHCT as its outcome. We are also targeting reductions in unprotected sex. CHCT necessitates the testing and mutual disclosure of both partners, conditions that are essential for improving subsequent outcomes such as disclosure of HIV status, sexual risk reduction, and improving treatment outcomes. Thus, improving rates of CHCT has the potential to improve health outcomes for heterosexual couples in a rural area of South Africa that is highly impacted by HIV. The results of our ongoing clinical trial will provide much needed information regarding whether a relationship-focused approach is effective in increasing rates of participation in CHCT. Our intervention represents an attempt to move away from individual-level conceptualizations, to a more integrated approach for HIV prevention. TRIAL REGISTRATION: Study Name: Couples in Context: An RCT of a Couples-based HIV Prevention InterventionClinicalTrials.gov identifier: NCT01953133.South African clinical trial registration number: DOH-27-0212-3937
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