Ion mass and energy selective hyperthermal ion-beam assisted deposition setup.

For the synthesis of high-quality thin films, ion-beam assisted deposition (IBAD) is a frequently used technique providing precise control over several substantial film properties. IBAD typically relies on the use of a broad-beam ion source. Such ion sources suffer from the limitation that they deliver a blend of ions with different ion masses, each of them possessing a certain distribution of kinetic energy. In this paper, a compact experimental setup is presented that enables the separate control of ion mass and ion kinetic energy in the region of hyperthermal energies (few 1 eV - few 100 eV). This ion energy region is of increasing interest not only for ion-assisted film growth but also for the wide field of preparative mass spectrometry. The setup consists of a constricted glow-discharge plasma beam source and a tailor-made, compact quadrupole system equipped with entry and exit ion optics. It is demonstrated that the separation of monoatomic and polyatomic nitrogen ions (N+ and N2+) is accomplished. For both ion species, the kinetic energy is shown to be selectable in the region of hyperthermal energies. At the sample position, ion current densities are found to be in the order of 1 µA/cm2 and the full width at half maximum of the ion beam profile is in the order of 10 mm. Thus, the requirements for homogeneous deposition processes in sufficiently short periods of time are fulfilled. Finally, employing the described setup, for the first time in practice epitaxial GaN films were deposited. This opens up the opportunity to fundamentally study the influence of the simultaneous irradiation with hyperthermal ions on the thin film growth in IBAD processes and to increase the flexibility of the technique.

[Public opinion on breast-feeding and infant nutrition: results of a questionnaire in North Rhine-Westphalia]. / Die Einstellung der Bevölkerung zum Stillen und zur Säuglingsernährung - Bevölkerungsbefragung in Nordrhein-Westfalen.

AIM: With the intention to create a basis for interventions on the promotion of breast-feeding, the public opinion on breast-feeding and infant nutrition in NRW was assessed. METHODS: A two-stage random sample of interviewees was drawn for a computer-assisted telephone survey (CATI). Methods applied on the selection of: 1. Households: 1.1. Gabler-Häder (n=1 811); 1.2. Onomastik (n=200); participants with a Turkish background of migration interviewed in German or Turkish language, alternatively: 2. Interviewees: Last Birthday method (n=2 011), age > or =18 years. RESULTS: Breast milk is the nutrition preferably recommended in the first six months, the knowledge of adjacent issues of infant nutrition has to be improved. The majority accepts supportive measures for breast-feeding. Different sources of information were assessed in Turkish and German participants. CONCLUSION: The survey supplies the background for the development of target group-specific information strategies which take specifically into account of issues attributable to ethnic differences and to reach the relatives and friends of young families, too.

[Community knowledge about stroke. A survey in the District of Wesel, Germany (2002)]. / Schlaganfallwissen der Bevölkerung. Survey im Kreis Wesel (2002).

Community knowledge of stroke signs and risk factors in Germany is poor, while lacking knowledge is an important cause for delays in hospital admission. In the Wesel district (North Rhine-Westphalia) the local health conference put this issue on its agenda and initiated a phone survey. The aim was to assess community knowledge of stroke symptoms and risk factors as well as self-reported prevalence of established risk factors; in addition, the role of information on stroke risk provided to patients by the general practitioner (GP) was to be estimated. The study population was defined as comprising all residents in the district of Wesel between 18 and 87 years of age (approx. 385,000 people). The sample of 1,089 persons was drawn randomly and the telephone survey was carried out by the CATI-Laboratory (Computer Assisted Telephone Interviews) at the Institute of Public Health (lögd, Bielefeld) between 18 February and 28 March 2002. A total of 1,089 people were interviewed, of whom 31.9% knew no symptom, 25.7% could name one symptom, 23.8% two symptoms and 18.6% knew three or more correct signs. Weakness/paralysis was named most frequently by 43.6% of the respondents. The majority of respondents named smoking as a risk factor (59.6%), while hypertension was mentioned by 39.4% of the participants. Among 555 respondents aged 45 years and older, 75.1% said they had never received a GP's advice on stroke risk, while 75.3% among these persons reported to have at least one risk factor. The present study shows a persistent lack of community knowledge about stroke. It is recommended that knowledge be improved especially with regard to (a) proper action: "stroke is a medical emergency-call the emergency telephone code 112", (b) symptoms and warning signs and (c) major stroke risk factors, especially high blood pressure. Moreover, information and advice on stroke should play a bigger part in the doctor's daily practice; patients should be made aware of their stroke risks and ways of prevention.

Tissue engineering of biphasic joint cartilage transplants.

In isolated posttraumatic or idiopathic joint defects the chondral layers and adjacent subchondral spongy bone are usually destructed. For regeneration we suggest the in vitro formation of a cartilage-coated biomaterial carriers (biphases) in order to fill the correspondingjoint defects. In this study Biocoral, a natural coralline material made of calcium carbonate, and calcite, a synthetic calcium carbonate, were used as supports for the cultivation of bovine chondrocytes in a three-dimensional polymer fleece. The cell-polymer-structure was affixed to the biomaterial with a fibrin-cell-solution. The artificial cartilage formed a new matrix and fused with the underlying biomaterial. The results indicate a promising technical approach to anchor tissue engineered cartilage in joint defects.

[Biliary ascariasis]. / Biliäre Ascariasis.

Biliary ascariasis is a complication of intestinal ascariasis. This results in characteristic findings in the intravenous cholangiocholecystogram and in the sonogram. Characteristic signs of biliary ascariasis are, in the longitudinal section, the "strip sign", "spaghetti sign", "inner tube sign", and in transverse section "a bull's eye in the triple O". The helminth can travel from out of the biliary duct system back into the intestines, so that control examinations can even be negative.