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We investigated the effect of mutual interference on the attack efficiency and the rate of successful parasitism on the parasitoid Spalangia cameroni (Perkins) attacking pupae of the stable fly Stomoxys calcitrans (L.). Female parasitoids (2, 4, 8, 16, or 32) were exposed to 100 fly pupae during 24 h. The number of pupae that were attacked and the number successfully parasitized increased with the parasitoid density and reached a maximum of ~70 and 50, respectively. Parasitoid-induced mortality (PIM) was about 20 pupae, irrespective of parasitoid density. The per capita rates of attack, successful parasitism and parasitoid-induced mortality declined monotonously with parasitoid density. Progeny sex ratio was female biased for all parasitoid densities, but declined significantly with increasing parasitoid density from ~70% females at the lowest density to ~60% at the highest. Mutual interference was incorporated into a functional response model to predict the attack rate and the rate of successful parasitism at different temperatures, host densities and parasitoid densities. The model explained 93.5% of the variation in the observed number of attacked pupae and 91.5% of the variation in the number of successfully parasitized pupae. The model predicts that increasing parasitoid densities will increase the percentage of killed hosts, but only up to a certain density. Above this density, a further increase in parasitoid abundance will actually lead to a decline in the percentage parasitism. These findings may have some implications for using S. cameroni in biological control against flies using inundative releases. [ABSTRACT FROM AUTHOR]

Study Objectives: To determine the prevalence of a history of sexual and physical abuse in women seen in a referral-based gastroenterology practice, to determine whether patients with functional gastrointestinal disorders report greater frequencies of abuse than do patients with organic gastrointestinal diseases, and to determine whether a history of abuse is associated with more symptom reporting and health care utilization.Design: A consecutive sample of women seen in a university-based gastroenterology practice over a 2-month period was asked to complete a brief questionnaire.Measurements: The self-administered questionnaire requested information about demographics, symptoms, health care utilization, and history of abuse. Physicians indicated the primary diagnosis for each patient and whether she had ever discussed having been sexually or physically abused.Results: Of 206 patients, 89 (44%) reported a history of sexual or physical abuse in childhood or later in life; all but 1 of the physically abused patients had been sexually abused. Almost one third of the abused patients had never discussed their experiences with anyone; only 17% had informed their doctors. Patients with functional disorders were more likely than those with organic disease diagnoses to report a history of forced intercourse (odds ratio, 2.08; 95% CI, 1.03 to 4.21) and frequent physical abuse (odds ratio, 11.39; CI, 2.22 to 58.48), chronic or recurrent abdominal pain (odds ratio, 2.06; CI, 1.03 to 4.12), and more lifetime surgeries (2.7 compared with 2.0 surgeries; P less than 0.03). Abused patients were more likely than nonabused patients to report pelvic pain (odds ratio, 4.05; CI, 1.41 to 11.69), multiple somatic symptoms (7.1 compared with 5.8 symptoms; P less than 0.001), and more lifetime surgeries (2.8 compared with 2.0 surgeries; P less than 0.01).Conclusions: We found that a history of sexual and physical abuse is a frequent, yet hidden, experience in women seen in referral-based gastroenterology practice and is particularly common in those with functional gastrointestinal disorders. A history of abuse, regardless of diagnosis, is associated with greater risk for symptom reporting and lifetime surgeries. [ABSTRACT FROM AUTHOR]