95 GHz gyrotron with ferroelectric cathode.

Ferroelectric cathodes were reported as a feasible electron source for microwave tubes. However, due to the surface plasma emission characterizing this cathode, operation of millimeter wave tubes based on it remains questionable. Nevertheless, the interest in compact high power sources of millimeter waves and specifically 95 GHz is continually growing. In this experiment, a ferroelectric cathode is used as an electron source for a gyrotron with the output frequency extended up to 95 GHz. Power above a 5 kW peak and ~0.5 µs pulses are reported; a duty cycle of 10% is estimated to be achievable.

The impact of Hymenoptera venom allergy on occupational activities.

The objective of this study was to investigate the impact of allergy to hymenoptera venom on the occupational activities of patients undergoing immunologic treatment for insect sting anaphylaxis. The design was a cross-sectional study conducted in a sample of 500 out of 1,500 patients undergoing venom immunotherapy for insect sting reaction in 13 allergy clinics in Israel. A self-administered questionnaire was used to collect data about demographic characteristics of patients, severity of the allergic reaction and adverse effects on occupational activities. Of the 204 respondents who were part of the labour force, 48.5% reported adverse effects on routine occupational activities. The factors with a significant influence on the probability of adverse occupational effects were: (1) patient's type of work (blue collar vs. white collar: OR = 3.22, p < 0.001: army vs. white collar: OR = 5.28, p = 0.001); (2) severity of the allergic reaction (severe reaction vs. mild/moderate reaction: OR = 2.34, p = 0.007). Our findings suggest that severe insect sting allergy has an adverse impact on patients' occupational activities. This factor requires special attention by the medical community. Social workers and occupational physicians should collaborate in the assessment and management of these patients.

Risk factors associated with the severity of systemic insect sting reactions.

To evaluate risk factors associated with the severity of systemic insect sting reaction and to determine the type of insect responsible for systemic anaphylaxis, we conducted a cross-sectional study of 498 patients undergoing venom immunotherapy for insect sting reaction in 13 allergy clinics in Israel. Data were collected by questionnaire and review of patient records. Eighty percent of the patients were treated with honeybee venom, which was used as a single therapy in 60% of the group. In a multivariate logistic model the major factors identified as significantly influencing the probability of a more severe systemic reaction were short time of onset of reaction after stinging (<30 min), high number of prior stings (> or = 4), and age (> or = 18 years). A total of 79.3% of the patients had been stung outdoors, and 50% had lived all their lives in rural areas as compared to 10% in the general Israeli population. This study reports clinically valuable risk factors for the severity of systemic sting reaction. A practical finding was that the honeybee is the insect mostly responsible for sting reactions in Israel, but the type of insect is not a significant predictor of the severity of the reaction.