Information-theoretic approaches to atoms-in-molecules : Hirshfeld family of partitioning schemes

Many population analysis methods are based on the precept that molecules should be built from fragments (typically atoms) that maximally resemble the isolated fragment. The resulting molecular building blocks are intuitive (because they maximally resemble well-understood systems) and transferable (because if two molecular fragments both resemble an isolated fragment, they necessarily resemble each other). Information theory is one way to measure the deviation between molecular fragments and their isolated counterparts, and it is a way that lends itself to interpretation. For example, one can analyze the relative importance of electron transfer and polarization of the fragments. We present key features, advantages, and disadvantages of the information-theoretic approach. We also codify existing information-theoretic partitioning methods in a way, that clarifies the enormous freedom one has within the information-theoretic ansatz

School-based intervention to improve the mental health of low-income, secondary school students in Santiago, Chile (YPSA): study protocol for a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>Depression is common and can have devastating effects on the life of adolescents. Psychological interventions are the first-line for treating or preventing depression among adolescents. This proposal aims to evaluate a school-based, universal psychological intervention to reduce depressive symptoms among student's aged 13-14 attending municipal state secondary schools in Santiago, Chile.</p> <p>Study design</p> <p>This is a cluster randomised controlled trial with schools as the main clusters. We compared this intervention with a control group in a study involving 22 schools, 66 classes and approximately 2,600 students. Students in the active schools attended 11 weekly and 3 booster sessions of an intervention based on cognitive-behavioural models. The control schools received their usual but enhanced counselling sessions currently included in their curriculum. Mean depression scores and indicators of levels of functioning were assessed at 3 and 12 months after the completion of the intervention in order to assess the effectiveness of the intervention. Direct and indirect costs were measured in both groups to assess the cost-effectiveness of this intervention.</p> <p>Discussion</p> <p>As far as we are aware this is the first cluster randomised controlled trial of a school intervention for depression among adolescents outside the Western world.</p> <p>Trial Registration</p> <p><a href="http://www.controlled-trials.com/ISRCTN19466209">ISRCTN19466209</a></p

Athanasios koukopoulos’ psychiatry: The primacy of mania and the limits of antidepressants

© 2017 Bentham Science Publishers. Background: Athanasios Koukopoulos provided a radical model for understanding depressive and manic conditions. Objective: To review, explain, and analyze Koukopoulos’ concept of the primacy of mania, with special attention to the role of antidepressants. Method: A conceptual review of Koukopoulos’ writings and lectures on this topic is given._ Results: Koukopoulos held that depressive states are caused by manic states; the former do not occur without the latter. The most common scenario of the inseparability of depressive and manic symptoms occurs in mixed states, which we estimate to represent about one-half of all depressive episodes in all patients (not just bipolar illness). In a review of the empirical evidence for this topic, we conclude that empirical evidence exists to support the primary of mania thesis in almost 80% of depressed patients. Since antidepressants worsen mania, they would be expected to worsen depression as well in this model.

Development and validation of a three-item version of the Edinburgh Postnatal Depression Scale

Objective To develop and validate a brief screening instrument for postpartum depression in resource-constrained primary care settings. Method Secondary data analysis of a cohort of 305 mothers (Mdn(age) = 26) attending well-child check-ups in six primary care centers in Santiago, Chile, answered the Edinburgh Postnatal Depression Scale (EPDS), the 36-Item Short Form Health Survey, and the Mini International Neuropsychiatric Interview depression module. A predictive model for postpartum depression was built using logistic and least absolute shrinkage and selection operator regressions, with bootstrap validation. Results A three-item version of the EPDS exhibited excellent discriminative capacity (cstatistic = 0.95) and showed no significant differences versus the full version of the EPDS (chi(2)(1) = 1.75,p = .187). The best trade-off between sensitivity (92.86%) and specificity (86.70%) was achieved at a cut-off score of 8/9. Conclusions The three-item version of the EPDS can save clinicians valuable time, which might potentially improve communication of results to patients.Universidad de Santiago de Chile Ministerio de Salud de Chile 4127-41LE12 ANID - Millennium Science Initiative/Millennium Institute for Research on Depression and Personality-MIDAP ANID Millennium Science Initiative, grant "Millennium Nucleus to Improve the Mental Health of Adolescents and Youths, Imhay

Marital functioning in couples practicing periodic abstinence for family planning

Objective: To compare dyadic (marital) functioning between users of natural family planning (NFP) and users of artificial methods of contraception (AMC). Method: A cross-sectional study was conducted in healthy, over eighteen-year-old couples living in stable relationships recruited from primary and secondary health centers in Santiago, Chile. Participants were assessed using a structured interview on sociodemographic and sexual aspects. Primary outcome, marital functioning, was studied using the Dyadic Adjustment Scale (DAS). Results: One hundred and thirty-eight couples were studied, sixty-nine in each user group. Both groups had a similar average time living together (124.3 vs. 126.9 months). DAS results were consistent with functional couples in both groups, but on average, the NFP group had a significantly higher DAS score than AMC. After controlling for age, socioeconomic status, time in the relationship, and religious commitment in multivariable analysis, the NFP group had a 47 percent (odds ratio = 1.47) greater possibility of having a functional marital score above the cutoff (DAS > 114) when compared with the AMC group. The AMC group reported more frequency of sexual intercourse but similar sexual satisfaction. Most (>60 percent) of the NFP couples mentioned that their methods improved their relationship. Conclusion: There are sociodemographic differences between both groups, explained partly by unequal access to NFP centers. Both groups have DAS scores within functional range, but NFP users have a higher probability of being in that functional range. This study of mentally and emotionally healthy couples highlights the importance of family planning methods on intimate relationships. Summary Marital functioning is affected by family planning methods. A structured interview and a specific inventory to address conjugal functioning were applied to a group of healthy couples who live in stable relationships and are users of natural family planning (NFP) or artificial methods of contraception (AMC). The results were consistent with functional couples in both groups, but on average, the NFP group had a significantly higher score than the AMC group. The use of NFP explained this difference. This study of mentally and emotionally healthy couples highlights the importance of family planning methods on intimate relationships.University of los Andes FAI PSI 002-0

Screening depressive episodes in adolescents. Validation of the patient health questionnaire-9 (PHQ-9)

Background: There is a paucity of validated instruments for screening depression in adolescent populations in Chile. Aim: To determine the diagnostic accuracy of the adolescent version of Patient Health Questionnaire-9 (PHQ-9). Material and Methods: The PHQ-9 was transculturally adapted and administered to adolescents aged 15 to 19 years residing in Santiago de Chile, who were then evaluated with a semi structured interview (Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version or K-SADS-PL) and the Beck Depression Inventory. Internal validity, concurrent validity, and discriminatory power of the PHQ-9 were analyzed. Results: We evaluated 245 adolescents aged 16.2 +/- 1 years (71% females). Two hundred and ten presented with a depressive episode and 35 were healthy. The sensitivity and specificity of the scale were 86.2 and 82.9% for 11 points, with a positive likelihood ratio of 5.02. Conclusions: The PHQ-9 is sensitive and specific enough to be used as a screening tool in adolescents with suspected depression. At a 11-point cut-off score as proposed, the likelihood to find a positive result in a subject with depression is five times higher