Characteristics, seasonality and sources of carbonaceous and ionic components in the tropical aerosols from Indian region

To better characterize the tropical aerosols in Indian region, PM<sub>10</sub> samples collected from Chennai, India (13.04° N; 80.17° E) were analyzed for carbonaceous and water-soluble ionic components. Concentration ranges of elemental carbon (EC) and organic carbon (OC) were 2.4–14 μg m<sup>−3</sup> (ave. 6.5 μg m<sup>−3</sup>) and 3.2–15.6 μg m<sup>−3</sup> (ave. 9.1 μg m<sup>−3</sup>) in winter samples whereas they were 1.1–2.5 μg m<sup>−3</sup> (ave. 1.6 μg m<sup>−3</sup>) and 4.1–17.6 μg m<sup>−3</sup> (ave. 9.7 μg m<sup>−3</sup>) in summer samples, respectively. Concentration of secondary organic carbon (SOC) retrieved from EC-tracer method was 4.6±2.8 μg m<sup>−3</sup> in winter and 4.3±2.8 μg m<sup>−3</sup> in summer. OC accounted for 38.5±14 % (<i>n</i> = 49) of combined concentrations of carbonaceous and ionic components in PM<sub>10</sub>. We also found that OC concentrations are generally higher than those of SO<sub>4</sub><sup>2−</sup> (8.8±2.5 μg m<sup>−3</sup> and 4.1±2.7 μg m<sup>−3</sup> in winter and summer, respectively), which was the most abundant ionic species (57 %) followed by NH<sub>4</sub><sup>+</sup> (15 %) >NO<sub>3</sub><sup>−</sup>>Cl<sup>−</sup>>K<sup>+</sup>>Na<sup>+</sup>> Ca<sup>2+</sup>>MSA<sup>−</sup>>Mg<sup>2+</sup>. The mass fractions of EC, organic matter (OM) and ionic species varied seasonally, following the air mass trajectories and corresponding source strength. Based on mass concentration ratios of selected components and relations of EC and OC to marker species, we found that biofuel/biomass burning is a major source of atmospheric aerosols in South and Southeast Asia. The high concentrations of SOC and WSOC/OC ratios (ave. 0.45; <i>n</i> = 49) as well as good correlations between SOC and WSOC suggest that the secondary production of organic aerosols during long-range atmospheric transport is also significant in this region. This study provides the baseline data of carbonaceous aerosols for southern part of the Indian subcontinent

Noncontact position measurement system using optical sensors

Optical and computational components are combined to form a high precision, six degree-of-freedom, single-sided, noncontact position measurement system. Reflective optical targets are provided on a target object whose position is to be sensed. Light beams are directed toward the optical targets, producing reflected beams. Electrical signals are produced indicating the points of intersection of the reflected beams and the position-sensitive detectors. The position sensitive detectors may be lateral-effect photodiodes. The signals are transformed to provide measurements of translation along and rotation around three nonparallel axes which define the space in which the target object moves.Board of Regents, University of Texas Syste

Reliability testing and stress measurement of QFN packages encapsulated by an open-ended microwave curing system

In this paper, the influence of microwave curing on the reliability of a representative electronic package is examined by reliability testing and measurement of residual stresses. A LM358 voltage regulator die was mounted to an open Quad Flat No-leads package (QFN) for reliability testing. For the stress measurement, a specifically designed stress measurement die was mounted to the QFN package. The chips were encapsulated with Hysol EO1080 thermosetting polymer material. Curing was performed using an open-ended microwave oven system equipped with in situ temperature control. Three different temperature profiles for microwave curing were selected according to the requested degree of cure and chemical composition of the cured material. A convection cure profile was selected for the control group samples. Thermal cycling and HAST tests were performed on a total number of 80 chips. 95 QFN packages with stress measurement chips were also manufactured. Increased lifetime expectancy of the microwave cured packaged chips was experimentally demonstrated and measured between 62% to 149% increased lifetime expectancy after Temperature Cycling Test (TCT), and between 63% and 331% after highly Accelerated Ageing Test (HAST) and TCT compared to conventionally cured packages. Analysis of specifically designed stress test chips showed significantly lower residual stresses ranging from 26 MPa to 58.3 MPa within the microwave cured packages compared to conventionally cured packaged chips which displayed residual stresses ranging from 54 MPa to 80.5 MPa. This article therefore provides additional confidence in the industrial relevance of the microwave curing system and its advantages compared to traditional convection oven systems

Type and duration of subsyndromal symptoms in youth with bipolar I disorder prior to their first manic episode

Objectives: The aim of the present study was to systematically evaluate the prodrome to mania in youth. Methods: New-onset/worsening symptoms/signs of \u3e= moderate severity preceding first mania were systematically assessed in 52 youth (16.2 +/- 2.8 years) with a research diagnosis of bipolar I disorder (BD-I). Youth and/or caregivers underwent semi-structured interviews, using the Bipolar Prodrome Symptom Scale-Retrospective. Results: The mania prodrome was reported to start gradually in most youth (88.5%), with either slow (59.6%) or rapid (28.8%) deterioration, while a rapid-onset-and-deterioration prodrome was rare (11.5%). The manic prodrome, conservatively defined as requiring \u3e= 3 symptoms, lasted 10.3 +/- 14.4 months [95% confidence interval (CI): 6.3-14.4], being present for \u3e= 4 months in 65.4% of subjects. Among prodromal symptoms reported in \u3e= 50% of youth, three were subthreshold manic in nature (irritability: 61.5%, racing thoughts: 59.6%, increased energy/activity: 50.0%), two were nonspecific (decreased school/work functioning: 65.4%, mood swings/lability: 57.7%), and one each was depressive (depressed mood: 53.8%) or subthreshold manic/depressive (inattention: 51.9%). A decreasing number of youth had \u3e= 1 (84.6%), \u3e= 2 (48.1%), or \u3e= 3 (26.9%) \u27specific\u27 subthreshold mania symptoms (i.e., elation, grandiosity, decreased need for sleep, racing thoughts, or hypersexuality), lasting 9.5 +/- 14.9 months (95% CI: 5.0-14.0), 3.5 +/- 3.5 months (95% CI: 2.0-4.9), and 3.0 +/- 3.2 months (95% CI: 1.0-5.0) for \u3e= 1, \u3e= 2, or \u3e= 3 specific symptoms, respectively. Conclusions: In youth with BD-I, a relatively long, predominantly slowonset mania prodrome appears to be common, including subthreshold manic and depressive psychopathology symptoms. This suggests that early clinical identification and intervention may be feasible in bipolar disorder. Identifying biological markers associated with clinical symptoms of impending mania may help to increase chances for early detection and prevention before full mania

Pharmacotherapy of bipolar disorder in children and adolescents: an update

Objective: To review the options for acute and maintenance pharmacological treatment of bipolar disorder in children and adolescents, including the treatment of bipolar depression and comorbid attention deficit/hyperactivity disorder (ADHD). Methods: Narrative review of randomized clinical trials and open-label studies published from 2000 to 2012. The PubMed and PsycINFO websites were queried. Case series were included when a higher level of evidence was not available. Results: Published data from randomized controlled trials (RCTs) in acute mania/hypomania with significant responses are available for lithium, topiramate, risperidone, olanzapine, and aripiprazole. Open trials of lithium and lamotrigine show that these drugs may be effective in the treatment of depressive episodes. No trials of selective serotonin reuptake inhibitors (SSRIs) have been conducted. In the treatment of comorbid ADHD, there are encouraging findings with mixed amphetamine salts and atomoxetine; conflicting results are observed with methylphenidate. Conclusions: Published RCTs of traditional mood stabilizers are scarce, but the best available evidence (results from meta-analytic regression) suggests that second-generation antipsychotics (SGAs) as a group are more effective in reducing manic symptoms. Risperidone was the only one included in head-to-head comparisons (vs. lithium and divalproex), showing superiority in terms of efficacy, but with more metabolic side effects, which were also more common in most of the SGAs. There are few studies addressing the treatment of ADHD and depression. Brazilian guidelines for the treatment of pediatric bipolar disorder should also include some SGAs (especially risperidone and aripiprazole) as first-line treatment, and these drugs should be provided by the public health services

Post-Acute Effectiveness of Lithium in Pediatric Bipolar I Disorder

This study examined the long-term effectiveness of lithium for the treatment of pediatric bipolar disorder within the context of combination mood stabilizer therapy for refractory mania and pharmacological treatment of comorbid psychiatric conditions

What do parents perceive are the barriers and facilitators to accessing psychological treatment for mental health problems in children and adolescents? A systematic review of qualitative and quantitative studies

A minority of children and adolescents with mental health problems access treatment. The reasons for poor rates of treatment access are not well understood. As parents are a key gatekeeper to treatment access, it is important to establish parents’ views of barriers/facilitators to accessing treatment. The aims of this study are to synthesise findings from qualitative and quantitative studies that report parents’ perceptions of barriers/facilitators to accessing treatment for mental health problems in children/adolescents. A systematic review and narrative synthesis were conducted. Forty-four studies were included in the review and were assessed in detail. Parental perceived barriers/facilitators relating to (1) systemic/structural issues; (2) views and attitudes towards services and treatment; (3) knowledge and understanding of mental health problems and the help-seeking process; and (4) family circumstances were identified. Findings highlight avenues for improving access to child mental health services, including increased provision that is free to service users and flexible to their needs, with opportunities to develop trusting, supportive relationships with professionals. Furthermore, interventions are required to improve parents’ identification of mental health problems, reduce stigma for parents, and increase awareness of how to access services