213 research outputs found

    Near-field cathodoluminescence studies on n-doped gallium nitride films

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    Near-field cathodoluminescence (NFCL) has been used to characterize hydride vapor phase epitaxy grown n-GaN films. This technique can obtain high resolution luminescence images and perform local measurements of the diffusion length for minority carriers in different parts of the sample. NFCL contrast observed in round growth hillocks at the sample surface, with a diameter of less than 10 mum, is compared with that observed by conventional cathodoluminescence in scanning electron microscope (CLSEM) techniques. In particular NFCL images reveal features not detected by CLSEM which is explained by the fact that under near field conditions the signal arises from a depth of only several tens of nanometers and is then directly related to the surface hillocks. Diffusion lengths of about 0.4 and 4 mum have been found for the holes in different regions of the samples at room temperature. The order of magnitude of these minority carriers diffusion lengths is in good agreement with previous measurements performed at different GaN samples with other techniques. The NFCL contrast and the differences in the measured diffusion lengths are discussed and explained by variations in local trap concentrations

    ELSID-diabetes study-evaluation of a large scale implementation of disease management programmes for patients with type 2 diabetes. Rationale, design and conduct : a study protocol

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    Background: Diabetes model projects in different regions of Germany including interventions such as quality circles, patient education and documentation of medical findings have shown improvements of HbA1c levels, blood pressure and occurrence of hypoglycaemia in before-after studies (without control group). In 2002 the German Ministry of Health defined legal regulations for the introduction of nationwide disease management programs (DMP) to improve the quality of care in chronically ill patients. In April 2003 the first DMP for patients with type 2 diabetes was accredited. The evaluation of the DMP is essential and has been made obligatory in Germany by the Fifth Book of Social Code. The aim of the study is to assess the effectiveness of DMP by example of type 2 diabetes in the primary care setting of two German federal states (Rheinland-Pfalz and Sachsen-Anhalt). Methods/Design: The study is three-armed: a prospective cluster-randomized comparison of two interventions (DMP 1 and DMP 2) against routine care without DMP as control group. In the DMP group 1 the patients are treated according to the current situation within the German-Diabetes-DMP. The DMP group 2 represents diabetic care within ideally implemented DMP providing additional interventions (e.g. quality circles, outreach visits). According to a sample size calculation a sample size of 200 GPs (each GP including 20 patients) will be required for the comparison of DMP 1 and DMP 2 considering possible drop-outs. For the comparison with routine care 4000 patients identified by diabetic tracer medication and age (> 50 years) will be analyzed. Discussion: This study will evaluate the effectiveness of the German Diabetes-DMP compared to a Diabetes-DMP providing additional interventions and routine care in the primary care setting of two different German federal states

    Diamond Luminescence

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    Luminescence spectroscopy is an established tool to investigate natural, high pressure synthesized, and chemical vapour deposited (CVD) diamond. The spectral range extends from 5.3 eV in the ultraviolet to approximately 1.2 eV in the near-infrared. More than 100 optical centres have been observed. Since the early 1930\u27s, semiconducting diamond for electronic devices has been of interest to science. The large bandgap (5.5 eV), low dielectric constant (5.7), and high thermal conductivity (about 5 times larger then that of Ag), as well as the superior charge-carrier transport properties, such as electron and hole mobility (µ-: 2200 cm2/Vs, μ+: 1600 cm2/Vs), lead to applications in active and passive electronics. At the beginning of the 1980\u27s, the first successful experiments of diamond films synthesis by low pressure chemical vapour deposition method were presented. Cathodoluminescence (CL) and photoluminescence (PL) are important techniques for characterising the defects present in CVD films and natural diamond. In this presentation, the most significant luminescence bands, the defects and the problems with the models used to interpret the bands are discussed

    Lobgesang auf den biologischen Vater als Störgeräusch

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    Determination of albuminuria in the urine of diabetics for prevention and control of diabetic nephropathy

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    The issue: Diabetes has become the main cause of endstage renal disease. The costs for the treatment of diabetic patients with endstage renal disease have increased in the last years and have become a relevant economic topic of the health service. The first unspecific predictor of a diabetic nephropathy is an albuminuria. The screening for diabetic nephropathy uses microalbuminuria as a proof. Objectives: * What significance does the determination of albuminuria have on the precaution and course-control of the diabetic nephropathy? a) in type 1 diabetic patients, b) in type 2 diabetic patients * Which is an appropriate time to determine the albuminuria for the purpose of precaution and course-control of the diabetic nephropathy? a) in type 1 diabetic patients, b) in type 2 diabetic patients * Which method of testing is most effective concerning economic and medical aspects? Methods: Published literature from 1998 up to 2004 was identified by searching in the most important databases. Most of the guidelines were found by hand searching in the internet. Results: Of 2,792 citation titles and abstracts examined, 274 articles were retrieved for full-text review. Five metaanalyses and reviews, one review about clearing of guidelines (regarding 18 international guidelines) and four guidelines met the inclusion criteria for screening for microalbuminuria and type 1 diabetes. Seven metaanalyses, one HTA report, one review about clearing of guidelines (regarding 17 international guidelines), and seven guidelines met the inclusion criteria for screening for microalbuminuria and type 2 diabetes.At the moment, the determination of albuminuria still has a great significance because it is recommended in most published literature and guidelines. The time to determine the albuminuria depends on the age of the patients and their type of diabetes. Type 2 diabetic patients should start the determination when the diabetes is diagnosed whereas the determination is recommended five years later when type 1 diabetic patients are concerned. Most guidelines recommend a screening for microalbuminuria every year. Discussion and conclusion: All guidelines and most of the literature recommend this screening. However, these recommendations are only based on expert consensus. The specificity of this screening is rather low. False positive tests in type 2 diabetic patients will cause psychological problems. A positive test leads to the recommendation to achieve "normal blood pressure" and "normoglycaemia" - but this applies to each diabetic patient. Based on these facts, the screening for albuminuria in type 1 or type 2 diabetes patients cannot be recommended as long as benefit has not been demonstrated by large, clinical, controlled trials. Without an evidence of the benefit, this screening cannot be economic

    Veränderungen des Bilds der Ehe im Recht

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    Der Beitrag analysiert das Bild der Ehe im Rechtssystem, insbesondere in Bezug auf den grundrechtlichen Schutz der Ehe. Obwohl das Recht im Allgemeinen nicht in Bildern arbeitet, spielt das Ehebild eine entscheidende Rolle im Eherecht, besonders hinsichtlich des grundrechtlichen Schutzes. Der Text untersucht die Verbindung zwischen dem gesellschaftlichen Ehebild und dem rechtlichen Rahmen sowie deren Auswirkungen auf das Institut der Ehe, wie es durch Artikel 6 Absatz 1 GG garantiert ist. Zudem werden grundlegende Aspekte der Institutsgarantie in Artikel 6 Absatz 1 GG beleuchtet. Dabei wird betont, dass die Ausgestaltung der Ehe im Eherecht dem gesellschaftlichen Ehebild entsprechen muss, während es dem Staat nicht erlaubt ist, ein eigenes Bild der Ehe vorzuschreiben.The article analyses the image of marriage in the legal system of Germany, especially in relation to the protection of marriage under fundamental rights. Although law generally does not work in images, the image of marriage plays a crucial role in marriage law, in particular with regard to fundamental rights protection. The text examines the link between the social image of marriage and the legal framework, as well as its impact on the institute of marriage as guaranteed by Article 6 (1) GG. In addition, fundamental aspects of the institute guarantee in Article 6 (1) GG are examined. It is emphasised that the design of marriage in marriage law must correspond to the social image of marriage, while the state is not allowed to prescribe its own image of marriage
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