Humans and other mammals exhibit a remarkable array of cyclical changes in physiology and behaviour. These are often synchronized to the changing environmental light-dark cycle and persist in constant conditions. Such circadian rhythms are controlled by an endogenous clock, located in the suprachiasmatic nuclei of the hypothalamus. This structure and its cells have unique properties, and some o...

Whenever unemployment stays high for an extended period, it is common to see analyses, statements, and rebuttals about the extent to which the high unemployment is structural, not cyclical. This essay views the Beveridge curve pattern of unemployment and vacancy rates and the related matching function as proxies for the functioning of the labor market and explores issues in that proxy relations...

Both hyperprolactinemia and depressive disorder are known manifestations of hypothyroidism. However, hyperprolactinemia with overt symptomatology per se has not been reported to precede all episodes of organic depressive disorder. We report a similar presentation.

Cyclical activity of GABAergic interneurons during theta rhythm could mediate phasic changes in strength of glutamatergic synaptic transmission in the hippocampal formation if presynaptic inhibition from activation of GABA(B) receptors is sufficiently rapid to change within a theta cycle. The experiments described here analyzed the time course of GABA(B) modulation using a heterosynaptic depres...

Populations of replicating entities frequently experience sudden or cyclical changes in environment. We explore the implications of this phenomenon via a environmental switching parameter in several common evolutionary dynamics models including the replicator dynamic for linear symmetric and asymmetric landscapes, the Moran process, and incentive dynamics. We give a simple relationship between ...

Endotoxin was given to grey collie dogs to investigate the mechanism of cyclic hematopoiesis. Over prolonged periods of daily administration, low doses of endotoxin (0.1 microgram/kg/day) failed to change the cycling of blood neutrophils or reticulocytes. However, higher doses of endotoxin maintained at a plateau level (5 microgram/kg/day) eliminated the cyclic changes in neutrophils and stabil...

This paper examines cyclical changes involving complementisers, for instance, whether in the history of English. Whether starts out as a pronoun and after frequent topicalisation is reanalysed as an element in the left-most layer of the sentence. The same is true with prepositional phrases that are fronted and then reanalysed as part of the CP layer. The paper uses a Minimalist approach in that...

Observed changes in corporation tax revenues from year to year, which include the effects of changes in tax rates, deductions and compliance, appear to be highly volatile relative to profits, the tax base. This paper examines whether the ‘built-in’ fiscal drag properties of corporation tax can be expected to display similar properties. Simple, conceptual modelling demonstrates that the corporat...

T e incorporation of color Doppler systems on trans\'aginal probes has made it possible to evaluate the normally occurring cyclical haemodynamic changes in the I"male pelvis. In addition to the depiction of major \ascularchannels, small intraparenchymal vessels within the uterus and ovaries can be easily demonstrated. While color flo\\ imaging improves the ability to demonstrate \ascular struct...

The demand for gasoline follows a seasonal cycle in Sweden. The paper investigates the response in prices and profits over the cycle. In contrast to what has been found for the gasoline market in the United States I find no support for seasonal price changes compatible with the recently developed theories for cyclical variations of intensity of competition. Some possible explanations for this d...