An Exploration of the Intersections Between Study Abroad and Attachment Theory

The purpose of this study was to explore the possible connections between a student studying abroad and his or her attachment style. The research focused on students from a single university who participated in full semester study abroad experiences. This study was guided by the following questions: Is there a correlation between studying abroad and a student having a secure attachment style? Are there elements of a study abroad program correlated with a secure attachment style? How do students with different attachment styles reflect upon their study abroad experience? The main results from this study indicated that students who study abroad tend to have a secure attachment style. Additionally, students with a secure attachment style were able to reflect more in depth upon their experience and exhibited greater overall gains from their semester abroad

Dynamics of Ca2+-Calmodulin–dependent Inhibition of Rod Cyclic Nucleotide-gated Channels Measured by Patch-clamp Fluorometry

Cyclic nucleotide-gated (CNG) ion channels mediate cellular responses to sensory stimuli. In vertebrate photoreceptors, CNG channels respond to the light-induced decrease in cGMP by closing an ion-conducting pore that is permeable to cations, including Ca2+ ions. Rod CNG channels are directly inhibited by Ca2+-calmodulin (Ca2+/CaM), but the physiological role of this modulation is unknown. Native rod CNG channels comprise three CNGA1 subunits and one CNGB1 subunit. The single CNGB1 subunit confers several key properties on heteromeric channels, including Ca2+/CaM-dependent modulation. The molecular basis for Ca2+/CaM inhibition of rod CNG channels has been proposed to involve the binding of Ca2+/CaM to a site in the NH2-terminal region of the CNGB1 subunit, which disrupts an interaction between the NH2-terminal region of CNGB1 and the COOH-terminal region of CNGA1. Here, we test this mechanism for Ca2+/CaM-dependent inhibition of CNGA1/CNGB1 channels by simultaneously monitoring protein interactions with fluorescence spectroscopy and channel function with patch-clamp recording. Our results show that Ca2+/CaM binds directly to CNG channels, and that binding is the rate-limiting step for channel inhibition. Further, we show that the NH2- and COOH-terminal regions of CNGB1 and CNGA1 subunits, respectively, are in close proximity, and that Ca2+/CaM binding causes a relative rearrangement or separation of these regions. This motion occurs with the same time course as channel inhibition, consistent with the notion that rearrangement of the NH2- and COOH-terminal regions underlies Ca2+/CaM-dependent inhibition

Computational study of H 2 binding to MH 3 (M = Ti, V, or Cr)

A series of amorphous materials based on hitherto elusive early transition metal hydrides MH 3 (M = Ti, V, and Cr) and capable of binding H 2 via the Kubas interaction has shown great promise for hydrogen storage applications, approaching US DoE system targets in some cases [Phys. Chem. Chem. Phys., 2015, 17, 9480; Chem. Mat., 2013, 25, 4765; J. Phys. Chem. C, 2016, 120, 11407]. We here apply quantum chemical computational techniques to study models of the H 2 binding sites in these materials. Starting with monomeric MH 3 (M = Ti, V, and Cr) we progress to M 2 H 6 and then pentametallic systems, analyzing the H 2 binding geometries, energies, vibrational frequencies and electronic structure, finding clear evidence of significant Kubas binding. Dihydrogen binding energies range from 22 to 53 kJ mol -1 . In agreement with experiment, we conclude that while TiH 3 binds H 2 exclusively through the Kubas interaction, VH 3 and CrH 3 additionally physisorb dihydrogen, making these more attractive for practical applications

Retrofitting reinforced concrete structures with FRP: Numerical simulations using multifiber beam elements

In structural engineering, seismic vulnerability reduction of existing structures is a crucial issue. External reinforcement by Polymer Reinforced Fibers (FRP) is an interesting tool in order to fulfill this aim. However, the use of FRP reinforcement as a retrofitting method is limited, one of the reasons being the lack of predicting numerical tools for cyclic loading. This paper presents a method to predict the behavior of beam-column structures considering the FRP reinforcement effect. It describes the construction of a 1D concrete constitutive model suitable for monotonic and cycling loadings. The model is inspired on two well-known concrete models, the first one based on the damage mechanics theory (La Borderie concrete damage model), and the second one based on experimental studies (Eid & Paultre's confined concrete model). Validation of the approach is done using experimental results on reinforced concrete beam and columns submitted to axial and flexural cyclic loading. The proposed method deals also with steel bar rupture considering low cycle fatigue effects. All the simulations are done using multifiber Timoshenko beam elements

Formation of Mn hydrides from bis(trimethylsilylmethyl) Mn(II):A DFT study

We recently reported the synthesis and characterization of KMH-1 (Kubas Manganese Hydride – 1 [L. Morris et al., Energy Environ. Sci., 2019, 12, 1580–1591]), a manganese hydride molecular sieve which, if incorporated into a hydrogen storage system, projects sufficient performance to realise the DOE system targets for H2 storage and delivery. KMH-1 is amorphous and paramagnetic, making its characterization challenging, and how it is formed from its simple Mn(II) organometallic precursors is not fully understood. In this contribution, we explore computationally several series of reactions that could occur in the production of KMH 1 from bis(trimethylsilylmethyl) manganese (II) (Mn(TMSM)2), including the formation of hydrides, ways to generate the extended structure and reactions to produce species with Mn(I) centres (KMH-1 is believed to contain a substantial proportion of Mn(I)). We show that the most likely route to the formation of Mn hydrides is via elimination of tetramethylsilane (TMS) by reaction of Mn(TMSM)2 with H2. These hydrides could then react to grow the extended KMH-1 structure via Mn hydride condensation reactions. Alternatively, multimetallic TMS-containing products could be formed via condensation reactions involving Mn(TMSM)2 and/or MnTMSM, after which the TMS ligand could be removed via elimination reactions with H2. The formation of Mn(I) centres from Mn(II) hydrides is most likely via H2 elimination from Mn(II) hydrides

Developmental fluoxetine exposure in zebrafish reduces offspring basal cortisol concentration via life stage-dependent maternal transmission

Fluoxetine (FLX) is a pharmaceutical used to treat affective disorders in humans, but as environmental contaminant also affects inadvertently exposed fish in urban watersheds. In humans and fish, acute FLX treatment and exposure are linked to endocrine disruption, including effects on the reproductive and stress axes. Using the zebrafish model, we build on the recent finding that developmental FLX exposure reduced cortisol production across generations, to determine possible parental and/or life-stage-dependent (age and/or breeding experience) contributions to this phenotype. Specifically, we combined control and developmentally FLX-exposed animals of both sexes (F0) into four distinct breeding groups mated at 5 and 9 months, and measured offspring (F1) basal cortisol at 12 dpf. Basal cortisol was lower in F1 descended from developmentally FLX-exposed F0 females bred at 5, but not 9 months, revealing a maternal, life-stage dependent effect. To investigate potential molecular contributions to this phenotype, we profiled maternally deposited transcripts involved in endocrine stress axis development and regulation, epigenetic (de novo DNA methyltransferases) and post-transcriptional (miRNA pathway components and specific miRNAs) regulation of gene expression in unfertilized eggs. Maternal FLX exposure resulted in decreased transcript abundance of glucocorticoid receptor, dnmt3 paralogues and miRNA pathway components in eggs collected at 5 months, and increased transcript abundance of miRNA pathway components at 9 months. Specific miRNAs predicted to target stress axis transcripts decreased (miR-740) or increased (miR-26, miR-30d, miR-92a, miR-103) in eggs collected from FLX females at 5 months. Increased abundance of miRNA-30d and miRNA-92a persisted in eggs collected from FLX females at 9 months. Clustering and principal component analyses of egg transcript profiles separated eggs collected from FLX-females at 5 months from other groups, suggesting that oocyte molecular signatures, and miRNAs in particular, may serve as predictive tools for the offspring phenotype of reduced basal cortisol in response to maternal FLX exposure

Interactive computer-based interventions for weight loss or weight maintenance in overweight or obese people

BACKGROUND: The World Health Organization (WHO) estimates that the number of obese or overweight individuals worldwide will increase to 1.5 billion by 2015. Chronic diseases associated with overweight or obesity include diabetes, heart disease, hypertension and stroke. OBJECTIVES: To assess the effects of interactive computer-based interventions for weight loss or weight maintenance in overweight or obese people. SEARCH METHODS: We searched several electronic databases, including CENTRAL, MEDLINE, EMBASE, CINAHL, LILACS and PsycINFO, through 25 May 2011. We also searched clinical trials registries to identify studies. We scanned reference lists of included studies and relevant systematic reviews. SELECTION CRITERIA: Studies were included if they were randomized controlled trials or quasi-randomized controlled trials that evaluated interactive computer-based weight loss or weight maintenance programs in adults with overweight or obesity. We excluded trials if the duration of the intervention was less than four weeks or the loss to follow-up was greater than 20% overall. DATA COLLECTION AND ANALYSIS: Two authors independently extracted study data and assessed risk of bias. Where interventions, control conditions, outcomes and time frames were similar between studies, we combined study data using meta-analysis. MAIN RESULTS: We included 14 weight loss studies with a total of 2537 participants, and four weight maintenance studies with a total of 1603 participants. Treatment duration was between four weeks and 30 months. At six months, computer-based interventions led to greater weight loss than minimal interventions (mean difference (MD) -1.5 kg; 95% confidence interval (CI) -2.1 to -0.9; two trials) but less weight loss than in-person treatment (MD 2.1 kg; 95% CI 0.8 to 3.4; one trial). At six months, computer-based interventions were superior to a minimal control intervention in limiting weight regain (MD -0.7 kg; 95% CI -1.2 to -0.2; two trials), but not superior to infrequent in-person treatment (MD 0.5 kg; 95% -0.5 to 1.6; two trials). We did not observe consistent differences in dietary or physical activity behaviors between intervention and control groups in either weight loss or weight maintenance trials. Three weight loss studies estimated the costs of computer-based interventions compared to usual care, however two of the studies were 11 and 28 years old, and recent advances in technology render these estimates unlikely to be applicable to current or future interventions, while the third study was conducted in active duty military personnel, and it is unclear whether the costs are relevant to other settings. One weight loss study reported the cost-effectiveness ratio for a weekly in-person weight loss intervention relative to a computer-based intervention as USD 7177 (EUR 5678) per life year gained (80% CI USD 3055 to USD 60,291 (EUR 2417 to EUR 47,702)). It is unclear whether this could be extrapolated to other studies. No data were identified on adverse events, morbidity, complications or health-related quality of life. AUTHORS' CONCLUSIONS: Compared to no intervention or minimal interventions (pamphlets, usual care), interactive computer-based interventions are an effective intervention for weight loss and weight maintenance. Compared to in-person interventions, interactive computer-based interventions result in smaller weight losses and lower levels of weight maintenance. The amount of additional weight loss, however, is relatively small and of brief duration, making the clinical significance of these differences unclear

Are Split Tablet Keyboards Better? A Study of Soft Keyboard Layout and Hand Posture

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