Photophysical and structural characterisation of in situ formed quantum dots.

Conjugated polymer-semiconductor quantum dot (QD) composites are attracting increasing attention due to the complementary properties of the two classes of materials. We report a convenient method for in situ formation of QDs, and explore the conditions required for light emission of nanocomposite blends. In particular we explore the properties of nanocomposites of the blue emitting polymer poly[9,9-bis(3,5-di-tert-butylphenyl)-9H-fluorene] together with cadmium sulphide (CdS) and cadmium selenide (CdSe) precursors. We show the formation of emissive quantum dots of CdSe from thermally decomposed precursor. The dots are formed inside the polymer matrix and have a photoluminescence quantum yield of 7.5%. Our results show the importance of appropriate energy level alignment, and are relevant to the application of organic-inorganic systems in optoelectronic devices.

Management of high blood cholesterol levels in Nova Scotian adults: comparison with the NCEP II and European clinical practice guidelines.

OBJECTIVE: To compare the prevalence of dietary and drug treatment for high blood cholesterol levels with indication for treatment according to the National Cholesterol Education Program (NCEP) II and European clinical practice guidelines. STUDY DESIGN: A population-based, cross-sectional study. PATIENTS AND METHODS: Data were from the 1995 Nova Scotia Health Survey. Patients were 2078 respondents aged 20 to 74 years who provided blood samples. Based on cardiovascular risk factors, respondents were compared with guidelines to determine eligibility for dietary and antilipemic drug therapy. RESULTS: According to the NCEP II and European guidelines, 21% and 13%, respectively, of the population were estimated to be dietary therapy candidates and 12% and 4%, respectively, were estimated to be candidates for antilipemic drug therapy. Less than half of the dietary therapy candidates, according to either guideline, reported being diagnosed, and only about half of those diagnosed reported having received dietary therapy. Overall, 6% to 15% of the NCEP II drug therapy candidates and 12% to 37% of the European drug therapy candidates were estimated to be receiving antilipemic drugs. Only about 45% of the NCEP II and 60% of the European drug therapy candidates reported being diagnosed as having high blood cholesterol levels, and only about 50% of the NCEP II- and 60% of the European-diagnosed drug therapy candidates reported having received dietary therapy. The estimated prevalence of antilipemic drug therapy among diagnosed drug therapy candidates was 12% to 29% for the NCEP II and 12% to 52% for the European guidelines. CONCLUSIONS: Dietary therapy and antilipemic drug therapy were underused relative to the NCEP II and European guidelines as a result of underdiagnosis and low use of treatment after diagnosis. Large differences in the recommendations of the 2 guidelines, however, show lack of consensus as to who should be treated and point to the need for additional research on this issue.

Underuse of acetylsalicylic acid in individuals with myocardial infarction, ischemic heart disease or stroke: data from the 1995 population-based Nova Scotia Health Survey.

OBJECTIVE: To determine current patterns of acetylsalicylic acid (ASA) use in Nova Scotia for individuals with self-reported myocardial infarction, stroke or ischemic heart disease. DESIGN: Descriptive, cross-sectional, population-based study using data from the 1995 Nova Scotia Health Survey (NSHS). The NSHS was based on a probability sample and was representative of the Nova Scotia adult population by age, sex and region. Survey data were obtained by standardized home interviews conducted by trained public health nurses. SETTING: The province of Nova Scotia in 1995. PARTICIPANTS: Survey respondents who reported having a myocardial infarction, stroke or ischemic heart disease were assessed. RESULTS: Among those who reported a history of myocardial infarction, stroke or ischemic heart disease, 55% (95% CI 47% to 63%), 49% (95% CI 38% to 61%) and 54% (95% CI 39% to 68%), respectively, reported using ASA at the time of the survey. Overall, only 53% of those with cardiovascular disease were using ASA. Exclusion of persons with potential contraindications to ASA did not significantly increase these proportions. CONCLUSIONS: ASA appears to be underused in those at high risk for future vascular events. Further research is required to investigate determinants of ASA use and to increase appropriate use of ASA.

Basic blue 148: a rapid stain for T helper cells.

After brief exposure to an aqueous solution of the oxazine textile dye C.I. basic blue 148 following fixation in 37% formalin, 95% ethanol and glacial acetic acid, T helper cell nuclei and cytoplasm in specimens of peripheral blood displayed a deep red-violet color. No other cell in normal blood or bone marrow specimens showed intense staining of this type. The total staining time is 1 min. Basic blue 148 stain is a promising technique for hematology and immunology laboratories as a rapid screening test for T helper cells in blood specimens using a microscopic slide and ordinary incandescent illumination.