Unprotected sex among gay/bisexual men throughout the AIDS epidemic has usually been described as... more Unprotected sex among gay/bisexual men throughout the AIDS epidemic has usually been described as unintentional due to a relapse from safer sex behavior. The term “barebacking” emerged among HIV-positive men explicitly seeking unprotected sex with seroconcordant partners, but has come into use in the larger gay community to simply mean condomless sex. Some men have also taken on the identity as a “barebacker.” The present study assessed prevalence and predictors of bareback identity in a sample 687 gay/bisexual men attending community events. Barebackers reported significantly more use of crystal methamphetamine and higher peer norms for unprotected sex; HIV-negative barebackers were higher in sexual compulsivity while HIV-positive barebackers were higher in romantic obsession as well as drug/alcohol influenced sexual expectancies. HIV prevention efforts targeting barebackers and barebacking must be carefully developed if programs and campaigns are to be effective given the open debates about this phenomenon in the gay community.
Centrifuge tests were carried out to confirm and determine the effect of different pure alcohols,... more Centrifuge tests were carried out to confirm and determine the effect of different pure alcohols, methyl t-butyl ether (MTBE) and mixtures of alcohols with gasoline and diesel on a thin disc of consolidated clay. The evolution of changes in the clay hydraulic conductivity with time was investigated and other structural changes due to chemical attack were monitored. The findings presented here demonstrate that the hydraulic conductivity of the clay appear to be generally related to the polarity of the chemicals and the dielectric constant. The cracking effect of butanol and MTBE on consolidated clay at low flow rate and low stress level was observed. The addition of ethanol or MTBE to diesel increased the clay permeability and the migration of organic chemical. The addition of ethanol to gasoline also caused an increase in the clay hydraulic conductivity. The effect of the association of alcohols with gasoline or diesel on the clay hydraulic conductivity is discussed, with a view to improving current pollution remediation techniques.
Morphological and molecular data of coelomycetes are analyzed. Taxonomic tools and species concep... more Morphological and molecular data of coelomycetes are analyzed. Taxonomic tools and species concepts are explored. The bimodal systematics approach is emphasized. A comprehensive case study on Colletotrichum is included.
The health habits of today's children will largely determine their subsequent health as adults of... more The health habits of today's children will largely determine their subsequent health as adults of the twenty-first century. Smoking, inactivity, poor dietary practices, drug and alcohol abuse, and other deleterious habits may develop early, yet exert lifelong influences. This paper contains a review of (a) statistics and research on major health status indicators in school-aged children, (b) behaviors that contribute to disease risk, and (c) school-based interventions designed to change risk behaviors and enhance wellness. Activities that can be initiated by classroom teachers are emphasized in the concluding section of the paper. Through early intervention, enhanced longevity and quality of life may be accomplished.
Purpose Our aim was to assess the content validity of the Patient-Reported Outcomes Measurement I... more Purpose Our aim was to assess the content validity of the Patient-Reported Outcomes Measurement Information System (PROMIS) social health item banks by comparing a prespecified conceptual model with concepts that focus-group participants identified as important social-health-related outcomes. These data will inform the process of improving health-related quality-of-life measures. Methods Twenty-five patients with a range of social limitations due to chronic health conditions were recruited at two sites; four focus groups were conducted. Raters independently classified participants’ statements using a hierarchical, nested schema that included health-related outcomes, role performance, role satisfaction, family/friends, work, and leisure. Results Key themes that emerged were fulfilling both family and work responsibilities and the distinction between activities done out of responsibility versus enjoyment. Although focus-group participants identified volunteerism and pet ownership as important social-health-related concepts, these were not in our original conceptual model. The concept of satisfaction was often found to overlap with the concept of performance. Conclusion Our conceptual model appears comprehensive but is being further refined to more appropriately (a) distinguish between responsibilities versus discretionary activities, and (b) situate the outcome of satisfaction as it relates to impairment in social and other domains of health.
Three hypotheses have been posited as competing explanations for the comorbidity or co-occurrence... more Three hypotheses have been posited as competing explanations for the comorbidity or co-occurrence of language difficulties and behavioural problems among children: (1) language difficulties confer risk for behaviour problems, (2) behaviour problems confer risk for language difficulties, and (3) shared risk factors account for their co-occurrence. We use a developmental psychopathology perspective to propose a model that integrates these explanations, and incorporates several potential moderating, mediating, and shared risk factors. We propose that temperamental negative emotionality and working memory deficits operate to initiate the pathway that may culminate in comorbid language and behaviour problems. We hypothesise that contextual factors (e.g. parent–child interactional processes) and child-specific factors (e.g. adaptive communication) may exacerbate or offset this risk and thus contribute to multiple developmental pathways. The proposed model underscores the importance of considering transactional processes from multiple domains to understand how configurations of risk and protective factors translate into different patterns of children’s linguistic and behavioural functioning.
While the authors that have contributed to this book believe that furthering the cause of equity ... more While the authors that have contributed to this book believe that furthering the cause of equity is a laudable goal, there are many people who benefit from existing unequal political arrangements. In this chapter, Georgia Miller and Gyorgy Scrinis argue that many of those currently directing the future of nanotechnology have a strong incentive to maintain these patterns of unequal distribution. They note that nanotechnology is arising from actions that align it with powerful economic and political interests in the Global North. Despite paying lip service to studying the “ethical, legal, and social implications” of nanotechnology, those who are driving the rapid expansion of nanotechnology have not shown any genuine commitment to reorienting the enterprise to human needs or a more equal society.
It has recently been shown that, in subthylakoid particles prepared using detergent, there is inh... more It has recently been shown that, in subthylakoid particles prepared using detergent, there is inhibition of oxygen production reactions in photosynthesis by thermodynamic feedback from oxygen build-up, with 50% inhibition at 230 kPa partial pressure of oxygen. This article presents a comprehensive analysis of laboratory data on the effects of high oxygen partial pressures on photosynthesis, and on photo-lithotrophic and chemo-organotrophic growth, of oxygen-producing organisms. The article also contains an analysis of the extent to which high oxygen concentrations occur at the site of photosystem II (PSII) activity under natural conditions today and in the past. The conclusion is that the oxygen concentrations found in nature are very unlikely to reach that needed to cause 50% inhibition of the photosynthetic oxygen production reaction in subthylakoid particles, but that it is just possible that a small part of the inhibition of photosynthesis and of photo-lithotrophic growth by oxygen can be attributed to inhibition of oxygen production by PSII.
Unprotected sex among gay/bisexual men throughout the AIDS epidemic has usually been described as... more Unprotected sex among gay/bisexual men throughout the AIDS epidemic has usually been described as unintentional due to a relapse from safer sex behavior. The term “barebacking” emerged among HIV-positive men explicitly seeking unprotected sex with seroconcordant partners, but has come into use in the larger gay community to simply mean condomless sex. Some men have also taken on the identity as a “barebacker.” The present study assessed prevalence and predictors of bareback identity in a sample 687 gay/bisexual men attending community events. Barebackers reported significantly more use of crystal methamphetamine and higher peer norms for unprotected sex; HIV-negative barebackers were higher in sexual compulsivity while HIV-positive barebackers were higher in romantic obsession as well as drug/alcohol influenced sexual expectancies. HIV prevention efforts targeting barebackers and barebacking must be carefully developed if programs and campaigns are to be effective given the open debates about this phenomenon in the gay community.
Centrifuge tests were carried out to confirm and determine the effect of different pure alcohols,... more Centrifuge tests were carried out to confirm and determine the effect of different pure alcohols, methyl t-butyl ether (MTBE) and mixtures of alcohols with gasoline and diesel on a thin disc of consolidated clay. The evolution of changes in the clay hydraulic conductivity with time was investigated and other structural changes due to chemical attack were monitored. The findings presented here demonstrate that the hydraulic conductivity of the clay appear to be generally related to the polarity of the chemicals and the dielectric constant. The cracking effect of butanol and MTBE on consolidated clay at low flow rate and low stress level was observed. The addition of ethanol or MTBE to diesel increased the clay permeability and the migration of organic chemical. The addition of ethanol to gasoline also caused an increase in the clay hydraulic conductivity. The effect of the association of alcohols with gasoline or diesel on the clay hydraulic conductivity is discussed, with a view to improving current pollution remediation techniques.
Morphological and molecular data of coelomycetes are analyzed. Taxonomic tools and species concep... more Morphological and molecular data of coelomycetes are analyzed. Taxonomic tools and species concepts are explored. The bimodal systematics approach is emphasized. A comprehensive case study on Colletotrichum is included.
The health habits of today's children will largely determine their subsequent health as adults of... more The health habits of today's children will largely determine their subsequent health as adults of the twenty-first century. Smoking, inactivity, poor dietary practices, drug and alcohol abuse, and other deleterious habits may develop early, yet exert lifelong influences. This paper contains a review of (a) statistics and research on major health status indicators in school-aged children, (b) behaviors that contribute to disease risk, and (c) school-based interventions designed to change risk behaviors and enhance wellness. Activities that can be initiated by classroom teachers are emphasized in the concluding section of the paper. Through early intervention, enhanced longevity and quality of life may be accomplished.
Purpose Our aim was to assess the content validity of the Patient-Reported Outcomes Measurement I... more Purpose Our aim was to assess the content validity of the Patient-Reported Outcomes Measurement Information System (PROMIS) social health item banks by comparing a prespecified conceptual model with concepts that focus-group participants identified as important social-health-related outcomes. These data will inform the process of improving health-related quality-of-life measures. Methods Twenty-five patients with a range of social limitations due to chronic health conditions were recruited at two sites; four focus groups were conducted. Raters independently classified participants’ statements using a hierarchical, nested schema that included health-related outcomes, role performance, role satisfaction, family/friends, work, and leisure. Results Key themes that emerged were fulfilling both family and work responsibilities and the distinction between activities done out of responsibility versus enjoyment. Although focus-group participants identified volunteerism and pet ownership as important social-health-related concepts, these were not in our original conceptual model. The concept of satisfaction was often found to overlap with the concept of performance. Conclusion Our conceptual model appears comprehensive but is being further refined to more appropriately (a) distinguish between responsibilities versus discretionary activities, and (b) situate the outcome of satisfaction as it relates to impairment in social and other domains of health.
Three hypotheses have been posited as competing explanations for the comorbidity or co-occurrence... more Three hypotheses have been posited as competing explanations for the comorbidity or co-occurrence of language difficulties and behavioural problems among children: (1) language difficulties confer risk for behaviour problems, (2) behaviour problems confer risk for language difficulties, and (3) shared risk factors account for their co-occurrence. We use a developmental psychopathology perspective to propose a model that integrates these explanations, and incorporates several potential moderating, mediating, and shared risk factors. We propose that temperamental negative emotionality and working memory deficits operate to initiate the pathway that may culminate in comorbid language and behaviour problems. We hypothesise that contextual factors (e.g. parent–child interactional processes) and child-specific factors (e.g. adaptive communication) may exacerbate or offset this risk and thus contribute to multiple developmental pathways. The proposed model underscores the importance of considering transactional processes from multiple domains to understand how configurations of risk and protective factors translate into different patterns of children’s linguistic and behavioural functioning.
While the authors that have contributed to this book believe that furthering the cause of equity ... more While the authors that have contributed to this book believe that furthering the cause of equity is a laudable goal, there are many people who benefit from existing unequal political arrangements. In this chapter, Georgia Miller and Gyorgy Scrinis argue that many of those currently directing the future of nanotechnology have a strong incentive to maintain these patterns of unequal distribution. They note that nanotechnology is arising from actions that align it with powerful economic and political interests in the Global North. Despite paying lip service to studying the “ethical, legal, and social implications” of nanotechnology, those who are driving the rapid expansion of nanotechnology have not shown any genuine commitment to reorienting the enterprise to human needs or a more equal society.
It has recently been shown that, in subthylakoid particles prepared using detergent, there is inh... more It has recently been shown that, in subthylakoid particles prepared using detergent, there is inhibition of oxygen production reactions in photosynthesis by thermodynamic feedback from oxygen build-up, with 50% inhibition at 230 kPa partial pressure of oxygen. This article presents a comprehensive analysis of laboratory data on the effects of high oxygen partial pressures on photosynthesis, and on photo-lithotrophic and chemo-organotrophic growth, of oxygen-producing organisms. The article also contains an analysis of the extent to which high oxygen concentrations occur at the site of photosystem II (PSII) activity under natural conditions today and in the past. The conclusion is that the oxygen concentrations found in nature are very unlikely to reach that needed to cause 50% inhibition of the photosynthetic oxygen production reaction in subthylakoid particles, but that it is just possible that a small part of the inhibition of photosynthesis and of photo-lithotrophic growth by oxygen can be attributed to inhibition of oxygen production by PSII.
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