Operational trials of different propriety lamella and BAF systems

Halcrow Scotland were appointed by Grampian Regional Council (now North of Scotland Water Authority) in April 1993 to carry out the Aberdeen Wastewater Treatment Feasibility Study. The study started with a verification of the flows and polluting loads generated within the catchment followed by a review of the treatment technologies available. The purpose of examining the available technologies was to ascertain the land areas required. Different technologies had different land requirements, and it was important to evaluate this for the site selection stage. Inevitably, conventional activated sludge treatment processes required the greater land take, but it was the only proven technology as far as the client was concerned. Other treatment processes, loosely termed "small footprint", could be accommodated within a much smaller area. The most promising of these processes was Biological Aerated Flooded Filters (BAFF), but at that time there were very few plants operating in the UK and none in Scotland. Halcrow recommended that the client establish pilot plant trials of the BAFF process. For minimal land take lamella plate separators would be required in the primary treatment stage and it was decided to include this compact settlement process (with or without chemical assistance) in the pilot plant trials

Blood Pressure and Cognitive Function in an African-American and a Caucasian-American Sample: The Maine-Syracuse Study

Objective: The primary purpose of this study was to examine associations between indices of blood pressure (BP) and cognitive function for African-American participants in the Maine-Syracuse Longitudinal Study (MSLS). Corresponding data for the Caucasian-American MSLS participants were included to provide a basis for comparison. Interactions of age with BP indices were also assessed in relation to cognitive function. Methods: Data were drawn from the baseline MSLS questionnaires, medical interviews and examinations, Wechsler Adult Intelligence Scale subtests, and measurements of BP for 1563 participants, of whom 147 were African American. Multiple linear regression analyses were employed to examine the relationship between several BP predictors and cognitive outcomes with statistical adjustment for demographic, psychosocial, and cardiovascular risk factors. Results: Significant inverse associations between BP indices and cognitive performance were obtained for both racial cohorts but were generally of higher magnitude for the African-American cohort. Interactions of BP with age were not obtained for any of the cognitive test scores. Conclusions: Elevations in BP are associated with poorer cognitive function for African-American and Caucasian-American cohorts. These associations are similar for younger and older participants

Relation Between Central Adiposity and Cognitive Function in the Maine–Syracuse Study: Attenuation by Physical Activity

Background. Previous studies have demonstrated a relationship between central adiposity and cognitive function. However, only some of these studies have adjusted for cardiovascular risk factors and cardiovascular disease, and none have also adjusted for physical activity level. Purpose. The purpose of the study was to examine the association between anthropometric measures of central adiposity (waist circumference and waist/hip ratio) and cognitive functioning with adjustment for cardiovascular disease risk factors and physical activity. Methods. Participants were 917 stroke- and dementia-free community-dwelling adults (59% women) in the Maine– Syracuse Study. The design was cross-sectional. Outcome measures included tests from the Wechsler Adult Intelligence Scale, the Halstead-Reitan Neuropsychological Battery, the Wechsler Memory Scale Revised, and the Mini-Mental State Examination

Homocysteine, type 2 diabetes mellitus, and cognitive performance: The Maine-Syracuse Study

Type 2 diabetes mellitus and higher total plasma homocysteine concentrations are each associated with an increased incidence of cardiovascular disease and with diminished cognitive performance. Relations between homocysteine concentrations and cardiovascular disease incidence are stronger in the presence of type 2 diabetes mellitus. Therefore, we hypothesized that relations between homocysteine concentrations and cognitive performance would be stronger in the presence of type 2 diabetes. We related homocysteine concentrations and cognitive performance on the Mini-Mental State Examination in 817 dementia- and stroke-free participants of the Maine-Syracuse Study, 90 of whom were classified with type 2 diabetes mellitus. Regardless of statistical adjustment for age, sex, gender, vitamin co-factors (folate, vitamin B6, vitamin B12), cardiovascular disease risk factors, and duration and type of treatment for type 2 diabetes mellitus, statistically significant inverse associations between homocysteine concentrations and cognitive performance were observed for diabetic individuals. The weaker inverse associations between homocysteine concentrations and cognitive performance obtained for non-diabetic individuals were not robust to statistical adjustment for some covariates. Interactions between homocysteine concentrations and type 2 diabetes mellitus are observed such that associations between homocysteine and cognitive performance are stronger in the presence of diabetes

Arterial Pulse Wave Velocity and Cognition With Advancing Age

We hypothesized that carotid-femoral pulse wave velocity (PWV), a marker of arterial stiffness, interacts with age such that the magnitude of associations between PWV and cognitive performance are greater with increasing age and that this interaction is observed despite adjustments for demographic variables, mean arterial pressure, and cardiovascular risk factors. PWV was estimated using applanation tonometry in 409 dementia- and stroke-free participants of the Maine-Syracuse Longitudinal Study (24 to 92 years of age; 62.3% women). Using linear regression analyses in a cross-sectional design, associations between PWV and age and the interaction of PWV and age were examined in relation to a global composite score, the Wechsler Adult Intelligence Scale Similarities test (abstract reasoning), and 4 cognitive domains indexed by multiple cognitive measures. Adjusting for age, gender, education, height, weight, heart rate, mean arterial pressure, and antihypertensive treatment, PWV-by-age interactions were obtained for the global, visual-spatial organization and memory, scanning and tracking, and verbal episodic memory composites, as well as similarities. The combination of higher PWV and age resulted in progressively lower cognitive performance. This finding was the same with an extended model, which also included adjustment for cardiovascular risk factors and other confounds. PWV interacts with age in a multiplicative way to exert a negative influence on cognitive performance level. Early interventions to prevent an increase in arterial stiffness could possibly play an important role in the preservation of cognitive ability

Unzipping Kinetics of Double-Stranded DNA in a Nanopore

We studied the unzipping kinetics of single molecules of double-stranded DNA by pulling one of their two strands through a narrow protein pore. PCR analysis yielded the first direct proof of DNA unzipping in such a system. The time to unzip each molecule was inferred from the ionic current signature of DNA traversal. The distribution of times to unzip under various experimental conditions fit a simple kinetic model. Using this model, we estimated the enthalpy barriers to unzipping and the effective charge of a nucleotide in the pore, which was considerably smaller than previously assumed.Comment: 10 pages, 5 figures, Accepted: Physics Review Letter

Entrances and exits: changing perceptions of primary teaching as a career for men

Original article can be found at: http://www.informaworld.com/smpp/title~content=t713640830~db=all Copyright Informa / Taylor and Francis. DOI: 10.1080/03004430802352087The number of men in teaching has always been small, particularly in early childhood, but those that do come into teaching usually do so for the same reasons as women, namely enjoyment of working with children, of wanting to teach and wanting to make a difference to children's lives. However, in two separate studies, the authors have shown that on beginning teacher training in 1998, and at the point of leaving the profession in 2005, men and women tend to emphasise different concerns. This article will explore those differences and seek possible explanations for how men's views of teaching might be changing over time.Peer reviewe

Homocysteine, Folate, and Vitamins B\u3csub\u3e6\u3c/sub\u3e and B\u3csub\u3e12\u3c/sub\u3e Blood Levels in Relation to Cognitive Performance: The Maine-Syracuse Study

Objective: Our objective was to examine associations among plasma homocysteine concentrations (tHcy), the tHcy-cofactors (folate, vitamins B6 and B12), and multiple domains of cognitive performance, with statistical adjustment for possible confounds, including cardiovascular disease risk factors (CVD-RF) and cardiovascular disease (CVD). Methods: Subjects were 812 partici- pants (58% women) of the Maine-Syracuse study who were free of dementia and stroke. Employing a cross-sectional design and multiple regression analyses, fasting concentrations of tHcy and its vitamin cofactors (folate, B6, and B12) were related to multiple domains of cognitive performance. Results: With adjustment for age, education, gender, ethnicity, and the vitamins, tHcy was inversely associated with visual-spatial organization, working memory, scanning-tracking, and abstract reasoning. The same results were found with adjustment for age, education, gender, ethnicity, CVD-RF, and CVD. Vitamin cofactors were positively related to cognitive performance, but with adjustment for CVD-RF and CVD, only vitamin B6 was related to multiple cognitive domains. Conclusions: The inverse association of tHcy with multiple domains of cognitive functioning is not necessarily dependent on vitamin levels, vitamin deficiency, prevalent CVD risk factors, and manifest CVD. Serum folate, serum B12, and plasma B6 vitamin concentrations are positively associated with cognitive performance. Investigation of other possible mechanisms (e.g., tHcy neurotoxicity) mediating tHcy associations with cognitive performance is important, as are clinical trials examining the efficacy of folate, vitamin B6, and vitamin B12 for maintenance of cognitive functioning