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Molybdenum disulfide (MoS2) is a popular lamellar material with desirable properties who's form, and function can vary widely, from particles to monolayer/μm thick films and applications in semiconductors to aerospace lubricants and many more. Physical vapor deposition (PVD) is commonly used to produce dense, conformal micron thick MoS2 coatings, but lacks the ability to coat more complex geometries due to line-of-sight constraints and typically exhibit amorphous or nanocrystalline microstructures. Atomic layer deposition (ALD) has also been employed to deposit monolayer to 10's of nanometers thick lamellar solids like MoS2 & WS2 in transistor, sensors or electrocatalyst applications but not commonly for applications as solid lubricants in aerospace like their PVD counterparts. While recent work has shown that ALD MoS2 can exhibit favorable microstructures for solid lubricant applications and allows for non-line of sight deposition on complex geometries, it has not been widely adopted due to high deposition temperatures (>500 °C) that can lead to softening of steel substrates. In this work, we show one of the first applications highlighting the use of ultra-thin (5–10 nm) low temperature (∼250 °C) MoS2 coatings as a promising solid lubricant for macroscale mechanical interfaces. Post-deposition chemical conversion of ALD MoOx to MoS2 by annealing in H2S at temperatures ranging from 200 to 550 °C resulted in highly-ordered basally-oriented surface microstructures. The results from this work suggest that converted-ALD MoS2 coatings can serve as viable solid lubricants for aerospace applications requiring low-temperature processing, including those with complex geometries.

Objective: The authors investigated binge drinking, alcohol expectancies, and risky and protective drinking behaviors in relation to disordered eating behaviors in male and female college students. Participants: The full sample consisted of 7,720 undergraduate students, 18 to 22 years of age. Drinking behaviors were analyzed in 4,592 recent drinkers. Methods: Participants anonymously completed a survey as part of a universal alcohol abuse prevention program between September 2007 and April 2008. Results: Co-occurring disordered eating behaviors and binge drinking characterized 17.1% of males and 19.0% of females. Rates of binge drinking were higher in those with disordered eating behaviors. Students with disordered eating behaviors also had more positive and negative alcohol expectancies and engaged in more risky and fewer protective drinking behaviors than their counterparts. Conclusions: Students with disordered eating behaviors have outcome expectancies and behavior patterns associated with problematic drinking. These findings may enhance prevention and intervention programs.

Our goals in this article were to use item response theory (IRT) to assess the relation of depressive symptoms to the underlying dimension of depression and to demonstrate how IRT-based measurement strategies can yield more reliable data about depression severity than conventional symptom counts. Participants were 3,403 children and adolescents from 12 contributing clinical and nonclinical samples; all participants had received the Kiddie Schedule of Affective Disorders and Schizophrenia for School-Aged Children. Results revealed that some symptoms reflected higher levels of depression and were more discriminating than others. Furthermore, use of IRT-based information about symptom severity and discriminability in the measurement of depression severity was shown to reduce measurement error and increase measurement fidelity. (Contains 5 footnotes, 6 tables, and 6 figures.)

The psychometric properties and factor structure of the Dysfunctional Attitudes Scale were examined in a sample of 422 male and female adolescents (ages 12-17) with current major depressive disorder. The scale demonstrated high internal consistency ([alpha] = 0.93) and correlated significantly with self-report and interview-based measures of depression. Confirmatory factor analysis indicated that a correlated 2-factor model, with scales corresponding to perfectionism and need for social approval, provided a satisfactory fit to the data. The goodness-of-fit was equivalent across sexes and age groups. The findings support the use of the Dysfunctional Attitudes Scale and its subscales in the assessment of clinically depressed adolescents. (Contains 4 tables and 1 footnote.)

Previous reviews of outpatient interventions for adolescent substance abuse have been limited in the extent to which they considered the methodological quality of individual studies. The authors assessed 31 randomized trials of outpatient interventions for adolescent substance abuse on 14 attributes of trial quality. A quality of evidence score was calculated for each study and used to compare the evidence in support of different outpatient interventions. Across studies, frequently reported methodological attributes included presence of an active comparison condition, reporting of baseline data, use of treatment manuals, and verification of self-reported outcomes. Infrequently reported attributes included power and determination of sample size, techniques to randomize participants to condition, specification of hypotheses and primary outcomes, use of treatment adherence ratings, blind assessment, and inclusion of dropouts in the analysis. Treatment models with evidence of immediate superiority in 2 or more methodologically stronger studies included ecological family therapy, brief motivational interventions, and cognitive-behavioral therapy. (Contains 4 tables.)

This study explored the interactive effect of substance abuse and depression on social competence among 106 adolescent inpatients (57% female, 86% Caucasian). Substance abuse and depression were conceptualized using dimensional ratings of illness severity based on adolescent interviews, whereas social competence was conceptualized using parent ratings of adolescent behavior. Cross-sectional analyses revealed that substance abuse and depression had a negative interactive effect on adolescent social competence: Higher severity levels of both dimensions were associated with lower levels of competence than accounted for by the additive effects of the two dimensions. These findings persisted when controlling for gender, race, and other common dimensions of psychopathology. Significant impairment in social competence occurred at subdiagnostic levels of substance abuse when depression severity was high, highlighting the value of assessing outcomes across the full range of severity.

The Treatment for Adolescents With Depression Study (TADS) was designed to compare the relative and combined effectiveness of cognitive behavior therapy (CBT) and fluoxetine, each of which had demonstrated efficacy in carefully controlled single-site studies. Models of CBT from these efficacy studies served as the foundation for the TADS psychosocial intervention. When interpreting the acute and long-term outcomes of TADS treatment in the context of other studies of CBT for major depression, it is critical to understand the process and the decision making that formed the TADS CBT intervention. The TADS CBT Committee reviewed meta-analyses of child and adolescent psychotherapy as well as studies of CBT for childhood and adolescent depression, relied on expert consultants, and evaluated the treatment process in a feasibility study to derive the essential components of TADS CBT. In this article we describe the rationale for the TADS CBT, the process of treatment design, and the immediate sources of the TADS treatment. Key decisions were made involving the degree of treatment structure, therapist flexibility versus cross-site consistency, duration and intensity of treatment, the involvement of family members in treatment, and core versus optional elements of the intervention.

For the Treatment for Adolescents With Depression Study (TADS), a cognitive-behavioral therapy (CBT) manual was developed with the aim of balancing standardization and flexibility. In this article, we describe the manual's case formulation procedures, which served as one major mechanism of flexibility in TADS CBT. We first describe the essential components of a cognitive-behavioral case formulation. We then present a rationale for including individualized case formulation in manual-based treatments and clinical effectiveness studies, and discuss the specific case of TADS. We illustrate case formulation in an effectiveness study with a composite "case" of a 15-year-old male treated with TADS CBT. Clinical implications and future directions are discussed.

For decades, density has been attributed as a critical aspect of the structure of sputter-deposited nanocrystalline molybdenum disulfide (MoS2) coatings impacting oxidation resistance and wear resistance. Despite its importance, there are few examples in the literature that explicitly investigate the relationship between the density and oxidation behaviors of MoS2 coatings. Aging and oxidation are primary considerations for the use of MoS2 coatings in aerospace applications as they inevitably experience prolonged storage in water and oxygen-rich environments prior to use. Oxidation that is either limited to the first few nanometers or through the bulk of the coating can result in seizure due to high initial coefficients of friction or component failure from excessive wear. High-sensitivity low-energy ion spectroscopy (HS-LEIS) and Rutherford backscattering spectrometry (RBS) are both used to understand the extent of oxidation throughout the first ∼10 nanometers of the surface of pure sputtered nanocrystalline MoS2 coatings after high-temperature aging and how it is impacted by the density of coatings as measured by RBS. Results show that low-density coatings (ρ = 3.55 g/cm3) exhibit a more columnar microstructure and voiding, which act as pathways for oxidative species to penetrate and interact with edge sites, causing severe surface and subsurface oxidation. Furthermore, HS-LEIS of surfaces sheared prior to oxidation reveals that the oxidation resistance of low-density MoS2 coatings can be significantly improved by shear-induced reorientation of the surface microstructure to a basal orientation and elimination of pathways for oxygen into the bulk through compaction of surface and subsurface voids. [ABSTRACT FROM AUTHOR]

Pure molybdenum disulfide (MoS2) solid lubricant coatings could attain densities comparable to doped films (and the associated benefits to wear rate and environmental stability) through manipulation of the microstructure via deposition parameters. Unfortunately, pure films can exhibit highly variable microstructures and mechanical properties due to processes that are not controlled during deposition (i.e., batch-to-batch variation). This work focuses on developing a relationship between density, hardness, friction, and wear for pure sputtered MoS2 coatings. Results show that dense films (ρ = 4.5 g/cm3) exhibit a 100 × lower wear rate compared to porous coatings (ρ = 3.04–3.55 g/cm3). The tribological performance of high density pure MoS2 coatings is shown to surpass that of established composite coatings, achieving a wear rate 2 × (k = 5.74 × 10–8 mm3/Nm) lower than composite MoS2/Sb2O3/Au in inert environments. [ABSTRACT FROM AUTHOR]