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411.
Stéphanie Watier-Grillot M. Boni C. Tong P.-A. Renoult A. Fournier L. Joie A. Mérens A. Chesnay S. Perelle A. Fraisse K. Ambert-Balay D. Chal S. Larréché R. Michel V. Pommier de Santi 《Food and environmental virology》2017,9(4):498-501
In January 2016, a large-scale outbreak of acute gastroenteritis was reported among French armed forces deployed in the Central African Republic. Challenging investigations, conducted from France, made it possible to identify a norovirus genogroup II in both stool and food samples, confirming a norovirus foodborne disease outbreak. Infected food handler management is discussed. 相似文献
412.
H. Günzler M. Waldmeier D. Stünkel H. Borchert F. Scheffer 《Die Naturwissenschaften》1963,50(15):531-532
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418.
Katja?Bonnevier Kai?Lindstr?mEmail author Colette?St. Mary 《Behavioral ecology and sociobiology》2003,53(6):358-363
Theory suggests that there is a trade-off between mate attraction and investment in parental care. Yet, under some circumstances, such as in species with uniparental male care, it is conceivable that males who provide more care also attract more females, and hence avoid this cost. We tested these two alternative hypotheses using the Florida flagfish, Jordanella floridae, which is a highly sexually dimorphic species with male parental care. We predicted that if components of male care behavior primarily serve offspring survival, they should display these behaviors more in the presence of eggs than without eggs. We also predicted that males should show a trade-off between display, and other activities directed to other fish, and care behaviors. Alternatively, if care has a positive effect on mating success, we expected males to show care even in the absence of eggs, and that they should display more care in the presence of females. We found that care behavior mostly depended on the presence of eggs, males increased care when they guarded eggs, and there was a negative relationship between rates of interaction and care behavior. Most care was exhibited in the absence of other fish while the presence of males and females both had a negative effect on care behavior. There was no difference in care behavior with males or females present. Only nest-visitation rates were highest in the presence of females, suggesting that this behavior is used as part of the courtship. These results support the idea that male care in this species is primarily influenced by natural selection. Males did, however, display fanning and other egg-directed behaviors even in the absence of eggs. The level of these behaviors was constant and independent of display behavior. Hence, it seems that care may be used in mate attraction before the male has received his first clutches. 相似文献
419.
Alison M. Barker Reitumetse Molotsane Caroline Müller Urs Schaffner Erich Städler 《Chemoecology》2006,16(4):209-218
Summary. The turnip sawfly Athalia rosae sequesters glucosinolates from its cruciferous host plants in the larval stage. Investigation of the chemosensory and behavioural
responses of adult A. rosae to glucosinolates and their volatile hydrolysis products, isothiocyanates, revealed that females detect glucosinolates by
contact chemoreception and isothiocyanates by antennal olfaction. In electroantennogram recordings, four isothiocyanates (allyl
[2-propenyl] isothiocyanate, benzyl isothiocyanate, butyl isothiocyanate and iberverin [3-methylthiopropyl isothiocyanate])
were active at all doses presented, including the lowest (0.1 μg), whilst the threshold for detection of three others, iberin
[3-methylsulphinylpropyl isothiocyanate], methyl isothiocyanate, and sulforaphane [4-methylsulphinylbutyl isothiocyanate],
was higher, at between 1 and 10 μg (source concentration of volatiles). Allyl isothiocyanate attracted experienced females
in a four-chambered olfactometer, whilst na?ve females showed no response. Allyl isothiocyanate also attracted mature females
to baited yellow water traps in field trials, although immature females were repelled at high isothiocyanate concentrations.
In laboratory behavioural bioassays the glucosinolates sinigrin (allyl [2-propenyl] glucosinolate) and sinalbin (p-hydroxybenzyl
glucosinolate), stimulated ovipositor probing in mature female A. rosae to an extent comparable to hot-water extracts of their host plants. These responses show that glucosinolates and isothiocyanates
play an important role in host finding and host recognition in A. rosae. 相似文献
420.
Dr. Elizabeth J. T. Winsor B. St. John Brown Edwin R. Luther Stephen A. Heifetz J. Philip Welch 《黑龙江环境通报》1987,7(7):485-489
A pregnancy was terminated because of persistently elevated amniotic fluid AFP (+10 S.D.) and an AChE band of low intensity on gel electrophoresis. No fetal anomalies were detected by ultrasonographic examination. Autopsy revealed an apparently normal fetus of about 20 weeks gestation. Attached to the placenta was a small sac containing a fetus papyraceus co-twin of about 8–9 weeks gestation. The small deceased co-twin and its gestational sac were not detected prenatally despite multiple ultrasonographic examinations. The difficulty in the interpretation of apparently conflicting results is emphasized. 相似文献