Photoactive thin silver films by atmospheric pressure CVD

We report the visible and UV activity of thin silver films. The films are grown using a CVD process employing aqueous-based silver precursors, flame-assisted chemical vapour deposition. This approach overcomes many of the previously encountered limitations to silver deposition by employing an atmospheric pressure process, low-cost and low-toxicity precursors. The resultant films are assessed for activity using stearic acid destruction as a model compound. We also report on the addition of titania to these silver films to increase the potential functionality. This activity is also demonstrated, where the films appear largely transparent to the eye, further widening the potential application of this work. It is speculated that the nanoparticulate nature, of the CVD silver, is crucial in determining photoactivity

The Dissipation of Urban High School Students\u27 Post-Secondary Educational Aspirations and Career Planning During the College Choice Process

Given the gap in the college choice literature about the decision-making process students use when making a decision on whether or not to attend college (McDonough & Calderone, 2010), the purpose of this study was to explore urban high school students’ perceptions of the structural factors that may influence their post-secondary educational aspirations and career plans. By working with students and guidance counselors at Sheridan High School, categorized as an urban high school but located in a rural area in the mid-Atlantic region of the country, the research team was able to gain information about how students navigate the college choice process and decide to enter or not to enter post-secondary education. Three supplemental theoretical approaches, the college choice model (Hossler & Gallagher, 1987), multicultural navigator model (Carter, 2005), and cultural capital and habitus theory (Bourdieu, 1977, 1990), were utilized in this study to analyze the social and cultural factors that impact urban students’ development of paths to post-secondary education. This study explored the challenges urban students face while navigating the college choice process and the strategies they use to surmount obstacles to enter post-secondary education. Nine students (African American and White) participated in the study over a three-year period at a high school categorized as an urban high school but located in a rural area in the mid-Atlantic region of the country. The students and their families lived either in the city of Sheridan or in three small rural towns within the district. At the start of the study, all of the students stated that their goal after graduating from Sheridan High School was to go to college. The study indicates that White students were significantly influenced by their parents, who made sure the students were in Sheridan’s Honors and International Baccalaureate programs, which were deemed to better prepare students for college by faculty, guidance counselors, and administrators in the school, whereas African American students (eligible for the free- and reduced-lunch program) did not received significant support or clear information about the college choice process from their parents; and the students did not develop succinct plans for post-secondary educational opportunities. There is ample research to support that African American students can achieve similar educational outcomes to White students if they are exposed to professionals and professional careers during their formative years (Freeman, 2005; McDonough & Calderone, 2010; Pitre, 2006). School officials should work with local social originations and community leaders to create and foster programs that engage professionals (mentorship, tutoring, career shadowing, college counseling) to help students develop and shape their post-secondary and career plans

The Dissipation of Urban High School Students\u27 Post-Secondary Educational Aspirations and Career Planning During the College Choice Process

Given the gap in the college choice literature about the decision-making process students use when making a decision on whether or not to attend college (McDonough & Calderone, 2010), the purpose of this study was to explore urban high school students’ perceptions of the structural factors that may influence their post-secondary educational aspirations and career plans. By working with students and guidance counselors at Sheridan High School, categorized as an urban high school but located in a rural area in the mid-Atlantic region of the country, the research team was able to gain information about how students navigate the college choice process and decide to enter or not to enter post-secondary education. Three supplemental theoretical approaches, the college choice model (Hossler & Gallagher, 1987), multicultural navigator model (Carter, 2005), and cultural capital and habitus theory (Bourdieu, 1977, 1990), were utilized in this study to analyze the social and cultural factors that impact urban students’ development of paths to post-secondary education. This study explored the challenges urban students face while navigating the college choice process and the strategies they use to surmount obstacles to enter post-secondary education. Nine students (African American and White) participated in the study over a three-year period at a high school categorized as an urban high school but located in a rural area in the mid-Atlantic region of the country. The students and their families lived either in the city of Sheridan or in three small rural towns within the district. At the start of the study, all of the students stated that their goal after graduating from Sheridan High School was to go to college. The study indicates that White students were significantly influenced by their parents, who made sure the students were in Sheridan’s Honors and International Baccalaureate programs, which were deemed to better prepare students for college by faculty, guidance counselors, and administrators in the school, whereas African American students (eligible for the free- and reduced-lunch program) did not received significant support or clear information about the college choice process from their parents; and the students did not develop succinct plans for post-secondary educational opportunities. There is ample research to support that African American students can achieve similar educational outcomes to White students if they are exposed to professionals and professional careers during their formative years (Freeman, 2005; McDonough & Calderone, 2010; Pitre, 2006). School officials should work with local social originations and community leaders to create and foster programs that engage professionals (mentorship, tutoring, career shadowing, college counseling) to help students develop and shape their post-secondary and career plans

Biocidal silver and silver/titania composite films grown by chemical vapour deposition

This paper describes the growth and testing of highly active biocidal films based on photocatalytically active films of TiO2, grownby thermal CVD, functionally and structurallymodified by deposition of nanostructured silver via a novel flame assisted combination CVD process. The resulting composite films are shown to be highly durable, highly photocatalytically active and are also shown to possess strong antibacterial behaviour. The deposition control, arising from the described approach, offers the potential to control the film nanostructure, which is proposed to be crucial in determining the photo and bioactivity of the combined film structure, and the transparency of the composite films. Furthermore, we show that the resultant films are active to a range of organisms, including Gram-negative and Gram-positive bacteria, and viruses. The very high-biocidal activity is above that expected from the concentrations of silver present, and this is discussed in terms of nanostructure of the titania/silver surface. These properties are especially significant when combined with the well-known durability of CVD deposited thin films, offering new opportunities for enhanced application in areas where biocidal surface functionality is sought

Highly bioactive silver and silver/titania composite films grown by chemical vapour deposition

This paper describes how photocatalytically active films of TiO2, grown by thermal CVD, may be functionally and structurally modified by deposition of nano-structured silver via a novel flame assisted CVD process. The resulting composite films are shown to be highly durable, highly photocatalytically active and are also shown to possess strong antibacterial behaviour. The deposition control, arising from the described approach, offers the potential to control the film nanostructure, which is proposed to be crucial in determining the photo and bio-activity of the combined film structure, and the transparency of the composite films. Furthermore, we show that the resultant films also exhibit “self-regeneration” capability, in that they both kill bacteria present on the film surface and then photo-degrade the residues. Such a dual action significantly reducing the problems of surface deactivation due to build up of contamination. These properties are especially significant when combined with the well-known durability of CVD deposited thin films, offering new opportunities for enhanced application in areas where bioactive surface functionality is sought

Cognitive leisure activities and future risk of cognitive impairment and dementia: systematic review and meta-analysis

BACKGROUND: As life expectancies continue to rise, modifiable lifestyle factors that may prevent cognitive decline and dementia in later life become increasingly important in order to maintain quality of life in old age. METHODS: Five meta-analyses were conducted on data from papers identified in a systematic review. Studies were grouped according to outcomes (dementia, cognitive impairment including amnestic Mild Cognitive Impairment (aMCI), Mild Cognitive Impairment (MCI), and cognitive decline) and output (risk (RR), odds (OR), or hazard ratios (HR)). RESULTS: Nineteen studies met our inclusion criteria and quality assessments. Four of five meta-analyses showed significant associations between participation in cognitive leisure activities and reduced risk of cognitive impairment (OR = 0.69, 95% CI: 0.56-0.85) and dementia (HR = 0.58, 95% CI: 0.46-0.74; RR = 0.61, 95% CI: 0.42-0.90; OR = 0.78, 95% CI: 0.67-0.90). However, one pooled analysis of cognitive impairment studies did not reach significance (HR = 0.85, 95% CI: 0.71-1.02). Mentally stimulating leisure activities were significantly associated with later life cognition (β = 0.11, p = 0.05), better memory (β = 0.20, 95% CI: 0.11-0.29), speed of processing (β = 0.37, 95% CI: 0.29-0.45), and executive functioning (β = 0.23, 95% CI: 0.15-0.29), and less decline in overall cognition (β = -0.23, p < 0.01), language (β = -0.11, p < 0.05), and executive functioning (β = -0.13, p < 0.05). Activities were also shown to reduce rate of cognitive decline (estimate = 0.03, SE = 0.01, p = 0.00). CONCLUSIONS: There is increasing evidence that participation in cognitively stimulating leisure activities may contribute to a reduction of risk of dementia and cognitive impairment in later life. Promoting involvement in such activities across lifespan could be an important focus for primary prevention strategies for governments and health services

The development and evaluation of individual Cognitive Stimulation Therapy (iCST) for people with dementia

Background: Cognitive Stimulation Therapy (CST) can improve cognition and quality of life (QoL) for people with dementia. However, previously this has only been delivered in a group format. Aim: To develop and evaluate the effectiveness of a home-based, carer-led individual CST (iCST) programme. Methods: The trial followed the Medical Research Council (MRC) framework. The development phase included; assessment of studies of home based cognitive stimulation, consultation with carers, people with dementia and healthcare professionals on the adaption of the CST and maintenance CST (maintenance CST) programmes, focus groups (n=32), ten interviews, a period of field-testing (n=22), an online survey and a consensus conference. A multi-centre, single-blind, pragmatic, randomised controlled trial (RCT) was conducted. In total, 356 people with mild to moderate dementia and their carers were recruited. Dyads were randomly assigned into the iCST arm (three, 30 minute sessions per week for 25 weeks plus support) or treatment as usual (TAU) control. The iCST training DVD was developed as part of the trial. Results: In the development phase the concept of iCST was well received, and both carers and people with dementia responded positively to the first drafts of materials. Anticipated issues, such as finding time to do sessions and suitability of the carer to deliver sessions were identified in the focus groups and interviews. The field-testing phase demonstrated that implementation of the iCST intervention was feasible. However, the majority of dyads completed fewer than three sessions per week. Identified barriers to participation included, lack of time, illness, and motivation. The training and support package appeared to be suitable as carers were able to deliver the intervention without intensive support. Two drafts of the materials were produced before a final version ready for use in the main RCT. Of the 180 iCST dyads, 134 (74%) were included in the intention to treat (ITT) analysis. There were 178 TAU dyads, of which 139 (78%) were available for analysis. At follow-up 2 (FU2) there were no significant differences between the iCST and TAU groups in the primary outcomes of cognition (Alzheimer’s Disease Assessment Scale - cognitive [ADAS-cog], SMD = -0·55, 95% CI -2·00,0·90; p=0·45) and self-reported QoL (Quality of Life Alzheimer’s Disease [QOL-AD], SMD = -0·02, 95% CI -1·22,0·82; p= 0·97). People with dementia receiving iCST rated the relationship with their carer more positively (SMD = 1·77, 95% CI 0·26,3·28; p= 0·02). No other secondary outcomes were significant. Conclusions: The rigorous development of the intervention was beneficial as the feasibility of the intervention was explored both in theory and practice. There was no evidence of iCST benefitting either cognition or QoL for the person with dementia. However, it did improve the relationship with the carer. Future work should investigate delivery of iCST by paid carers or professionals and developing the intervention for a computer platform

Optimizing the scale of markets for water quality trading

Applying market approaches to environmental regulations requires establishing a spatial scale for trading. Spatially large markets usually increase opportunities for abatement cost savings but increase the potential for pollution damages (hot spots), vice versa for spatially small markets. We develop a coupled hydrologic-economic modeling approach for application to point source emissions trading by a large number of sources and apply this approach to the wastewater treatment plants (WWTPs) within the watershed of the second largest estuary in the U.S. We consider two different administrative structures that govern the trade of emission permits: one-for-one trading (the number of permits required for each unit of emission is the same for every WWTP) and trading ratios (the number of permits required for each unit of emissions varies across WWTP). Results show that water quality regulators should allow trading to occur at the river basin scale as an appropriate first-step policy, as is being done in a limited number of cases via compliance associations. Larger spatial scales may be needed under conditions of increased abatement costs. The optimal scale of the market is generally the same regardless of whether one-for-one trading or trading ratios are employed