173 resultados para emission spectrum


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Anthropogenic elemental mercury (Hg0) emission is a serious worldwide environmental problem due to the extreme toxicity of the heavy metal to humans, plants and wildlife. Development of an accurate and cheap microsensor based online monitoring system which can be integrated as part of Hg0 removal and control processes in industry is still a major challenge. Here, we demonstrate that forming Au nanospike structures directly onto the electrodes of a quartz crystal microbalance (QCM) using a novel electrochemical route results in a self-regenerating, highly robust, stable, sensitive and selective Hg0 vapor sensor. The data from a 127 day continuous test performed in the presence of volatile organic compounds and high humidity levels, showed that the sensor with an electrodeposted sensitive layer had 260% higher response magnitude, 3.4 times lower detection limit (,22 mg/m3 or ,2.46 ppbv) and higher accuracy (98% Vs 35%) over a Au control based QCM (unmodified) when exposed to a Hg0 vapor concentration of 10.55 mg/m3 at 1016C. Statistical analysis of the long term data showed that the nano-engineered Hg0 sorption sites on the developed Au nanospikes sensitive layer play a critical role in the enhanced sensitivity and selectivity of the developed sensor towards Hg0 vapor.

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Research indicates significant health disparities for individuals with autism. Insight into characteristic sensory, cognitive, communication, social, emotional, and behavioural challenges that may influence health communication for patients with autism is vital to address potential disparities. Women with high functioning autism spectrum disorder (ASD) may have specific healthcare needs, and are likely to independently represent themselves and others in healthcare. A pilot study compared perceptions of healthcare experiences for women with and without ASD using on-line survey based on characteristics of ASD likely to influence healthcare. Fifty-eight adult female participants (32 with ASD diagnosis, 26 without ASD diagnosis) were recruited on-line from autism support organisations. Perceptions measured included self-reporting of pain and symptoms, healthcare seeking behaviours, the influence of emotional distress, sensory and social anxiety, maternity experiences, and the influence of autistic status disclosure. Results partially support the hypothesis that ASD women experience greater healthcare challenges. Women with ASD reported greater challenges in healthcare anxiety, communication under emotional distress, anxiety relating to waiting rooms, support during pregnancy, and communication during childbirth. Self-disclosure of diagnostic status and lack of ASD awareness by healthcare providers rated as highly problematic. Results offer detailed insight into healthcare communication and disparities for women with ASD.

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Listening to and reflecting on the voices and personal stories of adolescent students with an autism spectrum disorder (ASD) is critically important to developing more inclusive approaches to their education. This article considers the experiences of nine adolescents with an ASD on their inclusive education in a large urban secondary school in Australia. These educational experiences were mapped onto four themes emanating from a similar study by Humphrey and Lewis from the United Kingdom. The results from both studies suggest that although students with ASD are having positive and enabling educational experiences, a number of common inhibitors continue to prevent them from taking full advantage of their schooling. By listening to the voices of students with ASD, specific enablers and inhibitors to promoting successful educational experiences are identified, and recommendations for practice are put forward to better support the education not only of students with ASD but all students.

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Despite the high prevalence of infection by the Human Immunodeficiency Virus (HIV) in South Africa, information on its association with cancer is sparse. Our study was carried out to examine the relationship between HIV and a number of cancer types or sites that are common in South Africa. A total of 4,883 subjects, presenting with a cancer or cardiovascular disease at the 3 tertiary referral hospitals in Johannesburg, were interviewed and had blood tested for HIV. Odds ratios associated with HIV infection were calculated by using unconditional logistic regression models for 16 major cancer types where data was available for 50 or more patients. In the comparison group, the prevalence of HIV infection was 8.3% in males and 9.1% in females. Significant excess risks associated with HIV infection were found for Kaposi's sarcoma (OR=21.9, 95% CI=12.5–38.6), non-Hodgkin lymphoma (OR=5.0, 95%CI=2.7–9.5), vulval cancer (OR=4.8, 95%CI=1.9–12.2) and cervical cancer (OR=1.6, 95%CI=1.1–2.3) but not for any of the other major cancer types examined, including Hodgkin disease, multiple myeloma and lung cancer. In Johannesburg, South Africa, HIV infection was associated with significantly increased risks of Kaposi's sarcoma, non-Hodgkin lymphoma and cancers of the cervix and the vulva. The relative risks for Kaposi's sarcoma and non-Hodgkin lymphoma associated with HIV infection were substantially lower than those found in the West.