X-ray transport and radiation response assessment (XTRRA) experiments at the National Ignition Facility.

Our team has developed an experimental platform to evaluate the x-ray-generated stress and impulse in materials. Experimental activities include x-ray source development, design of the sample mounting hardware and sensors interfaced to the National Ignition Facility's diagnostics insertion system, and system integration into the facility. This paper focuses on the X-ray Transport and Radiation Response Assessment (XTRRA) test cassettes built for these experiments. The test cassette is designed to position six samples at three predetermined distances from the source, each known to within ±1% accuracy. Built-in calorimeters give in situ measurements of the x-ray environment along the sample lines of sight. The measured accuracy of sample responses as well as planned modifications to the XTRRA cassette is discussed.

Experimental comparison of a Shack-Hartmann sensor and a phase-shifting interferometer for large-optics metrology applications.

We performed a direct side-by-side comparison of a Shack-Hartmann wave-front sensor and a phase-shifting interferometer for the purpose of characterizing large optics. An expansion telescope of our own design allowed us to measure the surface figure of a 400-mm-square mirror with both instruments simultaneously. The Shack-Hartmann sensor produced data that closely matched the interferometer data over spatial scales appropriate for the lenslet spacing, and much of the <20-nm rms systematic difference between the two measurements was due to diffraction artifacts that were present in the interferometer data but not in the Shack-Hartmann sensor data. The results suggest that Shack-Hartmann sensors could replace phase-shifting interferometers for many applications, with particular advantages for large-optic metrology.

[Health promotion and prevention in the Lucerne canton--1995 analysis and prospects]. / Gesundheitsförderung und Prävention im Kanton Luzern--Analyse 1995 und Ausblick.

Considering the legal situation the canton of Lucerne is addressed to make his contribution to health promotion and prevention. His target groups are authorities on cantonal and community levels, specialised organisations and other health professionals, as for example physicians and pharmacists. The objectives of this study are to survey the health promotional and preventive activities, to evaluate the needs of the target groups as well as to focus on the opportunities of improved cooperation. Based on these results recommendations to the cantonal health authorities will be formulated. As far as the allocation of financial and personal resources are concerned health promotion and prevention do not figure as top priorities. Besides, the study results suggest to improve the cooperation between political representatives and health professionals. The cantonal health promotion authorities are well known among the target groups. However, cooperation could be intensified on all levels of action and is regarded as most desirable. A mutual forum focused on information and experience transfer would support these results and could stimulate joint projects. In addition, the needs of the communities have to be given special attention.

Hepatitis A infection in aircrews: risk of infection and cost-benefit analysis of hepatitis A vaccination.

BACKGROUND: Since a hepatitis A vaccine (HAV) with long-lasting efficacy has become available, its indication in airline crews needs to be determined. HYPOTHESIS: Destinations in developing countries are a risk factor for hepatitis A infection in airline crews, and vaccination is cost-beneficial. METHODS: Retrospective analysis was performed for all Swissair medical files for the period 1987-91. Denominator and cost data were obtained by the personnel department, and a cross-sectional seroepidemiological survey was performed in 734 Sabena staff. RESULTS: Among 3,322 Swissair crewmembers who spent an average of 45 nights in developing countries, 22 hepatitis A infections occurred. For the non-immune crewmembers, the overall annual incidence rate was 1.53 per 1000, whereas the incidence rate while staying in a high risk country was 12.2 per 1000. Cockpit crews with destinations limited to Europe had a rate of zero. Male flight attendants had a threefold higher rate as compared to female flight attendants or pilots. In Sabena, anti-HAV seroprevalence was 33.3%. Increased rates were observed in male as compared to female flying crews and in employees stationed abroad, whereas flying personnel had no higher rate than ground personnel. Simplified comparison of cost of infection and cost of vaccination indicates that vaccination may be cost-saving to the airline company for both male flight-attendants and pilots. CONCLUSIONS: Hepatitis A vaccination may be recommended to staff stationed in high risk countries and to flying crews with such destinations.

Alcohol and civil aviation.

In aviation medicine until the early 1960s the idea that pilots would fly while under the influence of alcohol was taboo. In the United States of America, the taboo was broken when it became known that 30% of fatally injured pilots in general aviation had been under the influence of alcohol. Since then the rate has declined to 10%. No fatal accidents involving alcohol have been recorded in airline passenger transport. The prevalence of pilots flying under the influence of alcohol is unknown. The lowest studied blood alcohol concentration (BAC) with impaired flying skill today is 0.025%, effectively suggesting that the permitted level should be zero, but many aviation authorities have not yet translated such findings into rules and regulations. In the early 1970s the US Federal Air Surgeon began to re-issue licences for rehabilitated alcoholic pilots. Previously alcoholism had been a reason for mandatory permanent grounding. The possibility of returning to the cockpit first opened the way to early recognition of alcoholic pilots on a larger scale. Today many airlines have their own alcohol programmes. This paper gives a brief account of the Swissair programme with its four phases: observation, intervention, treatment and follow-up.

[From malaria chemoprophylaxis to malaria self-treatment (1975-1989)]. / Von der Malaria-Chemoprophylaxe zur Malaria-Reservetherapie (1975 bis 1989).

Swissair's 3000-odd cockpit and cabin personnel spend an aggregate total of one year in the tropics for every ten years of flight service with the airline. Since 1975, company policy has been to issue all crews with a 'treatment dose' of anti-malaria medication to be taken if malaria contraction is suspected. Up until 1985, this treatment dose medication was recommended to crews for cases in which malaria was suspected even though chemoprophylactic medication had been taken. Since 1985, crews have been advised to rely solely on the treatment dose (i.e. not take any chemoprophylactic medication) if they are exposed to only low or moderate malaria risk. Experience so far has been encouraging: There has been no increase in incidences of malaria; the approach has been widely accepted among crews; the treatment dose (1%) has been judiciously used; the amount of chemoprophylactic tablets issued has declined; the number of repellents issued has increased; and the fear of side-effects from anti-malaria medication has decreased. The risk of contracting malaria-about one case per 200 to 300 years of service-is accepted. The question of whether and to what extent these experiences, which have been recorded among a small and selected group of the population, can be applied to other frequent flyers merits further investigation.

[Medical advice for travellers]. / Reisemedizinische Beratung.

When counselling travellers to overseas countries, attention should be paid not only to the health and safety conditions within the country of destination, but also to the general health of the traveller and to the personal risk he might take on his journey. Rarely, though, a person has to be discouraged from an overseas trip these days because of a constitutional or medical incapacity, a classification of which is given in the article. It is, however, indispensable to give advice on how to avoid exposure for a number of nuisances and diseases, particularly diarrhea, insect-stings and arthropod borne diseases and STD, as well as accidents.

[Vaccinations for travel abroad]. / Impfungen für Auslandreisen.

Travel to the developing world by Swiss citizens has been increasing. Vaccine-preventable diseases challenges the physician to provide pre-travel advice. Each traveler's itinerary, duration of stay and medical history, including previous immunization, should be reviewed. Vaccinations are required or recommended according to the requirements and the epidemiology of countries being visited. This article summarizes updated recommendations to individual vaccines and immunoglobulins.

Malaria prophylaxis and self-therapy in airline crews.

The risk of malaria infection in airline crews is estimated to be 0.5 per 1,000 persons per night in areas with high levels of malaria transmission. Routine chemoprophylaxis for years is not recommended because of possible side effects. Airline crews should therefore use appropriate measures to prevent mosquito bites. In addition, they may need to carry "standby" medication with them to be used for presumptive treatment of a febrile illness if medical attention is not readily available.

[Business travel and staying abroad]. / Berufsreisen und Aufenthalte im Ausland.

The growing internationalization of business and the economy is leading more and more working people to spend short or even long stays abroad. With fast journeys across several time zones, travellers are mainly confronted with problems of time difference adjustment, commonly known as "jet lag". For longer stays, especially when the family comes along too, a number of additional difficulties may arise which are not normally faced by tourists. People's physical ability to tolerate a long stay in the tropics is rarely questioned nowadays, except in cases of serious physical illness. However, the effects of such stays on an individual's psychological condition are receiving increasing attention. Inoculations and advice are largely determined by the epidemiology of infectious diseases and the medical infrastructure of the country of destination. Death caused by illness can almost always be avoided through the appropriate prophylaxis and/or therapy. Unfortunately, the same does not apply to accidents. The local medical infrastructure in the larger cities of the developing countries and the range of flights available for sick and injured people are continually improving with a few exceptions.

Physiologic changes in pregnant women and their fetuses during jet air travel.

The physiologic reactions of pregnant women and their fetuses were studied during routine commercial flights. Ten healthy pregnant women (32 to 38 weeks of gestation) each undertook two flights. Maternal respiratory and heart rates, transcutaneous PO2 and PCO2, blood pressure, uterine activity, and fetal beat-to-beat heart rate variability were continuously monitored. During these flights, maternal heart rate and blood pressure increased, and PO2 decreased significantly while PCO2 remained unchanged. Respiratory rate showed a short increase during takeoff and landing but remained unchanged during the rest of the flight. Mean fetal heart rate was within normal limits during the whole flight. No bradycardia, prolonged tachycardia, or significant loss of heart rate variability was observed. This study indicates no hazards of commercial flights to the mother and the fetus in uncomplicated pregnancies.

Hepatitis virus infection in flying airline personnel.

Sera of 1126 flying personnel of an airline were tested for signs of ongoing or past infections with hepatitis B virus (HBV) or with hepatitis A virus (HAV). The prevalence of anti-HA antibodies was similar in all professional categories of flying personnel and the same or slightly lower than in Swiss blood donors. The frequency of immune markers identifying HBV immunity was similar in pilots, flight-engineers, and female flight attendants compared to Swiss blood donors. However, HBV immunity was clearly more prevalent in male flight attendants. Within 1 year, 13 of 2624 flying personnel had acute hepatitis. This higher-than-average incidence of hepatitis amongst flying personnel compared to the Swiss population was mainly due to a high incidence of hepatitis B amongst male flight attendants. Their special life-styles might be responsible for the high prevalence of HBV immunity and for the high incidence of hepatitis B.