498 research outputs found
Recommended from our members
Taming Self-Organization Dynamics to Dramatically Control Porous Architectures
We demonstrate templating of functional materials with unexpected and intricate micro- and nanostructures by controlling the condensation, packing, and evaporation of water droplets on a polymer solution. Spontaneous evaporation of a polymer solution induces cooling of the liquid surface and water microdroplet condensation from the ambient vapor. These droplets pack together and act as a template to imprint an entangled polymer film. This breath figure (BF) phenomenon is an example of self-organization that involves the long-range ordering of droplets. Equilibrium-based analysis provides many insights into contact angles and drop stability of individual drops, but the BF phenomenon remains poorly understood thus far, preventing translation to real applications. Here we investigate the dynamics of this phenomenon to separate out the competing influences and then introduce a modulation scheme to ultimately manipulate the water vapor− liquid equilibrium independently from the solvent evaporation. This approach to BF control provides insights into the mechanism, a rationale for microstructure design, and evidence for the benefits of dynamical control of self-organization systems. We finally present dramatically different porous architectures from this approach reminiscent of microscale Petri dishes, conical flasks, and test tubes.The financial support of Science Foundation Ireland (Grant No. 06/IN.1/I106) and the Australian Research Council grants scheme are gratefully acknowledged.This is the author accepted manuscript. The final version is available from the American Chemical Society via http://dx.doi.org/10.1021/acsnano.5b0608
The adaptation of a community-based suicide prevention intervention during the COVID19 pandemic: a mixed methods study
Objective: To investigate the outcomes of men using a community-based suicide prevention service before and during COVID-19 and to understand experiences of therapists for the rapid adaptation and delivery of the service throughout the pandemic.
Methods: A mixed-methods approach using quantitative and qualitative data to assess the delivery of the intervention before and during the COVID-19 pandemic. The CORE-34 and CORE-10 Clinical Outcome Measures (CORE-OM) were used pre and post intervention to measure clinical change in psychological distress for the men engaged with the service. Six therapist interviews were used to supplement this data for the purposes of understanding the delivery of the service remotely during the pandemic. Data was collected between 1st August 2018 and 1st November 2021 (n=1115). Interview data were conducted between March and May 2021.
Results: Across the cohort, for men who received therapy before (n=450) or during the pandemic (n=665), there was a statistically significant reduction in mean psychological distress scores between assessment and end of treatment (p<0.001). Therapists adapted to delivering the hybrid model and discussed the barriers and facilitators to working this way.
Conclusions: This study highlighted the effectiveness of the James’ Place suicide prevention model in saving lives and managing to adapt during a global pandemic
A Case Series Study of Help-Seeking among Younger and Older Men in Suicidal Crisis
Due to the continuing high suicide rates among young men, there is a need to understand help-seeking behaviour and engagement with tailored suicide prevention interventions. The aim of this study was to compare help-seeking among younger and older men who attended a therapeutic centre for men in a suicidal crisis. In this case series study, data were collected from 546 men who were referred into a community-based therapeutic service in North West England. Of the 546 men, 337 (52%) received therapy; 161 (48%) were aged between 18 and 30 years (mean age 24 years, SD = 3.4). Analyses included baseline differences, symptom trajectories for the CORE-34 Clinical
Outcome Measure (CORE-OM), and engagement with the therapy. For the CORE-OM, there was a clinically significant reduction in mean scores between assessment and discharge (p < 0.001) for
both younger and older men. At initial assessment, younger men were less affected by entrapment (46% vs. 62%; p = 0.02), defeat (33% vs. 52%; p = 0.01), not engaging in new goals (38% vs. 47%; p = 0.02), and positive attitudes towards suicide (14% vs. 18%; p = 0.001) than older men. At discharge assessment, older men were significantly more likely to have an absence of positive future thinking (15% vs. 8%; p = 0.03), have less social support (45% vs. 33%; p = 0.02), and feelings of entrapment (17% vs. 14%; p = 0.02) than younger men. Future research needs to assess the long-term effects of help-seeking using a brief psychological intervention for young men in order to understand whether the effects of the therapy are sustainable over a period of time following discharge from the service
A Case Series Study of an Innovative Community- based Brief Psychological Model for Men in Suicidal Crisis
• Objectives –To conduct a 1-year evaluation of James’ Place, a suicidal crisis centre delivering a clinical intervention in a community setting.
• Design – A case series study, following men entering the service during the first year of operation.
• Participants – Men experiencing a suicidal crisis referred to the service (N=265), with N=176 going on to engage in therapy.
• Intervention – The James’ Place Model is a therapeutic intervention offered to men who are in a suicidal crisis. Trained therapists provide a range of therapeutic approaches and interventions, focusing on decreasing suicidal distress and supporting men to develop resilience and coping strategies.
• Main outcome measures - CORE-34 Clinical Outcome Measure (CORE-OM).
• Results - For all subscales of the CORE-OM there was a significant reduction in mean scores between assessment and discharge (p <0.001), with all outcomes demonstrating a large
effect size. All reductions illustrated a clinically significant change or a reliable change.
• Conclusions - Our results support the use of the James’ Place Model for men in suicidal
distress to aid in potentially preventing suicides in this high risk group of the population
Noisy Monte Carlo: Convergence of Markov chains with approximate transition kernels
Monte Carlo algorithms often aim to draw from a distribution by
simulating a Markov chain with transition kernel such that is
invariant under . However, there are many situations for which it is
impractical or impossible to draw from the transition kernel . For instance,
this is the case with massive datasets, where is it prohibitively expensive to
calculate the likelihood and is also the case for intractable likelihood models
arising from, for example, Gibbs random fields, such as those found in spatial
statistics and network analysis. A natural approach in these cases is to
replace by an approximation . Using theory from the stability of
Markov chains we explore a variety of situations where it is possible to
quantify how 'close' the chain given by the transition kernel is to
the chain given by . We apply these results to several examples from spatial
statistics and network analysis.Comment: This version: results extended to non-uniformly ergodic Markov chain
Tobacco use and asking prices of used cars: prevalence, costs, and new opportunities for changing smoking behavior
Secondhand smoke (SHS) causes premature death and disease in children and adults, and the scientific evidence indicates that there is no risk-free level of exposure to SHS. Smoking tobacco in a car can pollute the microenvironment of the car with residual SHS, leaving telltale signs to potential buyers (e.g., odor, used ash tray). This study examined (a) the proportion of used cars sold in the private party market that may be polluted with tobacco smoke and (b) whether asking prices of smoker and nonsmoker cars differed for cars of otherwise equivalent value. A random sample of 1,642 private party sellers were interviewed by telephone, and content analyses of print advertisements were conducted. Findings indicate that 22% of used cars were advertised by smokers or had been smoked in during the previous year. Among nonsmokers, 94% did not allow smoking in their car during the past year. Only 33% of smokers had the same restrictions. The smoking status of the seller and tobacco use in the car were significantly (p < .01) associated with the asking price independent of a car's Kelley Blue Book value (KBB). Used nonsmoker cars were offered at a considerable premium above their KBB value (>11%) and above comparable smoker cars (7–9%). These findings suggest that community preferences are affecting the value of smoke-free cars. New directions for research, tobacco control policies, and health education are discussed to further reduce smoking behavior, to help consumers make informed purchasing decisions, and to protect nonsmokers from SHS exposure
Injuries, Ill-Health and Fatalities in White Water Rafting and White Water Paddling
White water (WW) activities such as paddling (canoeing and kayaking) and rafting are popular sports for recreational and professional participants. An increase in participation has been seen worldwide. However, these activities come with a risk of injury and even death if not conducted safely. A review was conducted to identify the types of injuries and ill-health that occur as a result of these activities. Injury and fatality rates were assessed to establish the risk attributed to these activities. Web of Science, PubMed, Ergonomics Abstracts and PsycINFO databases were searched and a total of 16 published articles were identified and reviewed. The shoulders and back were the most vulnerable sites for injury in WW paddling. Injuries to the face and lower limbs were most common in WW rafters. However, injury rates are low and estimates are discussed. Due to different methods used across the studies, the reported injury rates are not comparable. This review identified three illnesses incurred through WW activities. There may be more but these are not currently reported in the literature. A relative paucity of studies regarding injuries and fatalities in WW activities was identified. Directions for future research are suggested and discussed
Tamoxifen-elicited uterotrophy: cross-species and cross-ligand analysis of the gene expression program
<p>Abstract</p> <p>Background</p> <p>Tamoxifen (TAM) is a well characterized breast cancer drug and selective estrogen receptor modulator (SERM) which also has been associated with a small increase in risk for uterine cancers. TAM's partial agonist activation of estrogen receptor has been characterized for specific gene promoters but not at the genomic level <it>in vivo</it>.Furthermore, reducing uncertainties associated with cross-species extrapolations of pharmaco- and toxicogenomic data remains a formidable challenge.</p> <p>Results</p> <p>A comparative ligand and species analysis approach was conducted to systematically assess the physiological, morphological and uterine gene expression alterations elicited across time by TAM and ethynylestradiol (EE) in immature ovariectomized Sprague-Dawley rats and C57BL/6 mice. Differential gene expression was evaluated using custom cDNA microarrays, and the data was compared to identify conserved and divergent responses. 902 genes were differentially regulated in all four studies, 398 of which exhibit identical temporal expression patterns.</p> <p>Conclusion</p> <p>Comparative analysis of EE and TAM differentially expressed gene lists suggest TAM regulates no unique uterine genes that are conserved in the rat and mouse. This demonstrates that the partial agonist activities of TAM extend to molecular targets in regulating only a subset of EE-responsive genes. Ligand-conserved, species-divergent expression of carbonic anhydrase 2 was observed in the microarray data and confirmed by real time PCR. The identification of comparable temporal phenotypic responses linked to related gene expression profiles demonstrates that systematic comparative genomic assessments can elucidate important conserved and divergent mechanisms in rodent estrogen signalling during uterine proliferation.</p
Rederivation of transgenic mice from iPS cells derived from frozen tissue
In mice, induced pluripotent stem (iPS) cells with embryonic stem (ES)-like characteristics have been derived by ectopic expression of four transcription factors in somatic cells: Sox2, Oct3/4, Klf4 and/or c-Myc. To date, iPS cells have only be made from freshly harvested tissues and cells. However, if iPS cells could be derived from frozen tissues and cells, then cryopreservation of tissues such as mouse tails could conceivably become a reliable alternative to the more traditional formats, like germplasm and ES cells, for the archiving of genetically altered mouse lines. To test this hypothesis, we sought to demonstrate that a live transgenic mouse line could be recovered from transgenic iPS cells derived from cryopreserved mouse tissues. Tails and tail-derived fibroblasts from a DsRED transgenic mouse were cryopreserved in the presence of 5% dimethylsulfoxide (DMSO) in liquid nitrogen for 1 week and 1 month, respectively. Afterward, tissues and cells were thawed and underwent nuclear reprogramming by molecular transfection to derive iPS cells which generated germline confirmed transgenic mice. Our results demonstrate for the first time that iPS cells can be efficiently derived from frozen-stored-thawed tail tissue and fibroblasts and used to re-establish a transgenic mouse line. Therefore, this study provides conclusive evidence that, as a practical matter, frozen tails and fibroblasts can be used as an effective and reliable alternative to frozen germplasm and ES cells for the storage, maintenance, and distribution of genetically-altered mutant mice
Influences of H on the Adsorption of a Single Ag Atom on Si(111)-7 × 7 Surface
The adsorption of a single Ag atom on both clear Si(111)-7 × 7 and 19 hydrogen terminated Si(111)-7 × 7 (hereafter referred as 19H-Si(111)-7 × 7) surfaces has been investigated using first-principles calculations. The results indicated that the pre-adsorbed H on Si surface altered the surface electronic properties of Si and influenced the adsorption properties of Ag atom on the H terminated Si surface (e.g., adsorption site and bonding properties). Difference charge density data indicated that covalent bond is formed between adsorbed Ag and H atoms on 19H-Si(111)-7 × 7 surface, which increases the adsorption energy of Ag atom on Si surface
- …