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31.
G. Fox Wilson 《The Annals of applied biology》1943,30(4):364-370
The results of experiments on the infection of many different plants with seven biologic strains of known history of the nematode, Anguillulina dipsaci (Kühn), are given, together with the results obtained by other investigators. The technique by which the nematode was induced to infect other host plants is described in detail. The biologic strain theory in relation to A. dipsaci is discussed, together with the merits of the trinomial system of nomenclature in connexion with unspecialized races. The factors concerned with nematode outbreaks receive consideration. The relationship that exists between flower colour in herbaceous phloxes and the degree of infection by A. dipsaci is presented. 相似文献
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Hydrobiologia - During the summer of 1969, fourteen Guatemalan lakes were sampled, including eight in the lowland northern province of Peten and six in southern Guatemala. The majority of the Peten... 相似文献
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Michael A. Fox 《Bulletin of mathematical biology》1973,35(1-2):11-17
Complexity and stability are the ubiquitous characteristics of all biological phenomena. The theoretical suggestions presented
here acknowledge this and attempt to capitalize on the property of selectiveness that complexity induces. It is from this
that a belief in the existence of selection rules emerges. What is required of a viable theory is a linguistic means of maneuvering
known information so that these selection or limitation rules may be obtained, and thence, by their manipulation, to generate
the properties exhibited by biological systems. 相似文献
35.
The de Broglie wave equation has been applied to the study of amoeboid motility. This leads to precise predictions of wavelengths displayed by the cellular membrane during motility. Motile amoeba are compared to non-biological systems showing de Broglie wave behavior, and three simple experiments are suggested. 相似文献
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Often we must balance being prepared to act quickly with being prepared to suddenly stop. The stop signal task (SST) is widely used to study inhibitory control, and provides a measure of the speed of the stop process that is robust to changes in subjects’ response strategy. Previous studies have shown that preparation affects inhibition. We used fMRI to separate activity that occurs after a brief (500 ms) warning stimulus (warning-phase) from activity that occurs during responses that follow (response-phase). Both of these phases could contribute to the preparedness to stop because they both precede stop signals. Warning stimuli activated posterior networks that signal the need for top-down control, whereas response phases engaged prefrontal and subcortical networks that implement top-down control. Regression analyses revealed that both of these phases affect inhibitory control in different ways. Warning-phase activity in the cerebellum and posterior cingulate predicted stop latency and accuracy, respectively. By contrast, response-phase activity in fronto-temporal areas and left striatum predicted go speed and stop accuracy, in pre-supplementary motor area affected stop accuracy, and in right striatum predicted stop latency and accuracy. The ability to separate hidden contributions to inhibitory control during warning-phases from those during response-phases can aid in the study of models of preparation and inhibitory control, and of disorders marked by poor top-down control. 相似文献