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IUMS NewsInternational Union of Microbiological Societies Newsletter 相似文献
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Ficus burtt-davyi, like most other fig species (Ficus, Moraceae), is exclusively pollinated by its own unique species of fig wasp, in this caseElisabethiella baijnathi (Chalcidoidea, Agaonidae). Because fig crop development on any one tree is usually synchronised, the small and short-lived
female wasps have to migrate and find other trees bearing figs which are at suitable stage of development for oviposition.
However, the likelihood of successful location and subsequent arrival at a new host tree is dependent on distance and the
effect of environmental factors such as wind and temperature. This study examines the relationship between ambient temperatures
and the timing of fig wasps emergence from their natal figs and the commencement of their dispersal flight. The behaviour
of the wasps arriving at figs which were ready to be pollinated was also examined. The female wasps did not appear to distinguish
between the figs and other parts of the tree when in flight. However, after landing on the tree their search for figs was
more directed as they visited more figs than leaves. Short-range recognition of figs appears to be by contact chemo-reception,
but the wasps showed a preference for entering figs which did not already contain a female wasp. 相似文献
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S?awomir Tubek 《Biological trace element research》2007,115(3):301
A negative relationship between water hardness and cardiovascular mortality rate was demonstrated and became a source of interest
regarding minerals and trace metals in the pathogenesis of atherosclerosis, cardiovascular diseases, and arterial hypertension.
Higher incidences of sudden death, cerebrovascular diseases, arterial hypertension, and coronary heart disease have been reported
in soft water areas. Amajor research effort has been devoted to the problem in an attempt to find a protective factor in hard
water or a detrimental factor or element in soft water. The roles of calcium, magnesium, cobalt, lithium, vanadium, silicon,
manganese, and copper have been considered potentially beneficial, whereas those of cadmium, lead, silver, zinc, and thallium
have been considered potentially harmful. Cobalt and zinc have been attributed both roles. In the present article, the role
of trace quantities of several elements in mineral water in the etiopathogenesis of primary arterial hypertension is reviewed. 相似文献