The cattle lice of Great Britain Part II. Lice populations

Parasitology ◽  
1941 ◽  
Vol 33 (3) ◽  
pp. 343-358 ◽  
Author(s):  
H. J. Craufurd-Benson
Keyword(s):  
Great Britain ◽  
Seasonal Variations ◽  
Climatic Factors ◽  
Regional Distribution ◽  
Field Research ◽  
Rapid Decline ◽  
Research Station ◽  
Seasonal Fluctuations ◽  
Host Animal ◽  
June July

1. The seasonal variations and regional distribution of the cattle lice have been studied by monthly examinations of cattle at the Cooper Field Research Station.2. Additional evidence has been obtained by the distribution of a questionnaire to farmers, the general results of which are included in this paper.3. The seasonal variations of the populations of the four species of cattle lice in Great Britain are similar. The maximum population density is reached in February and March. In April and May there is a rapid decline until the populations reach their lowest level in June, July and August. In September, the lice start increasing in numbers till they reach their maximum density in February and March.4. The regional distribution of the population varies in accordance with the seasonal variations of the whole population.5. The various climatic factors that may affect the lice populations are discussed. It is considered that the light intensity is a factor of major importance in this country.6. The various factors inherent in the host animal are discussed, and it is suggested that the seasonal fluctuations of the density of the animal's coat are important.7. The finding of a previous paper (Craufurd-Benson, 1941) that the microclimatic temperature is important as affecting the hatching of eggs is discussed in relation to the variations of lice populations as a whole.

A quantitative study of the helminth parasites of the Newfoundland short-finned squid, Illex illecebrosus illecebrosus (LeSueur) (Cephalopoda:Decapoda)

1968 ◽  
Vol 46 (6) ◽  
pp. 1087-1093 ◽  
Author(s):  
Elizabeth L. Brown ◽  
William Threlfall
Keyword(s):  
Quantitative Study ◽  
Seasonal Variations ◽  
Standard Length ◽  
New Records ◽  
Parasite Burden ◽  
Late Summer ◽  
Eastern Coast ◽  
Published Data ◽  
Helminth Parasites ◽  
Host Animal

Ommastrephid squid of the subspecies Illex illecebrosus illecebrosus (LeSueur) were obtained during the late summer and early autumn of 1966 and 1967 from numerous areas around the eastern coast of the island of Newfoundland. Helminths of five genera were found, namely, Phyllobothrium sp. and Dinobothrium plicitum (both of which had previously been recorded from this host), Pelichnibothrium speciosum, Scolex polymorphus, and Nybelinia sp. The last three represent new records from this ommastrephid. The incidence of these parasites was tested for correlation with standard length and with sex of the host animal. Annual and seasonal variations in degree of infection were also noted. The greatest number of procercoids encountered were Dinobothrium plicitum. Degree of infection with helminths in 1966 and 1967 was similar (39%:40%) and contrary to earlier published data, infection by cestodes is not always directly correlated with mantle length. Any possible relations between sex of the squid and parasite burden are unclear.

scholarly journals Field Research and Conservation

2013 ◽  
Vol 36 ◽  
pp. 179-180
Author(s):  
Chuck Collis ◽  
Jennifer Adams
Keyword(s):  
Behavioral Ecology ◽  
National Park ◽  
Biological Process ◽  
Field Research ◽  
Research Station ◽  
Surrounding Area ◽  
Research Experiences ◽  
Political Processes ◽  
Term Field

The Field Research & Conservation class emphasizes long-term field research experiences, examines ecosystem processes, and investigates the evolution of American perspectives about nature. Our time spent at the UW-NPS research station was divided between pursuing behavioral ecology research and exploring Grand Teton National Park and the surrounding area to gain understanding of how the region was shaped, both by geological and biological process as well as political processes that have been shaped by America’s ever-changing conservation ethic.

Nitrogen Transformations and Removal in Waste Stabilization Ponds in Portugal: Seasonal Variations

1987 ◽  
Vol 19 (12) ◽  
pp. 123-130 ◽  
Author(s):  
M. C. R. Santos ◽  
J. F. S. Oliveira
Keyword(s):  
Seasonal Variations ◽  
Climatic Factors ◽  
Weather Conditions ◽  
Organic N ◽  
Nitrogen Transformations ◽  
Waste Stabilization Ponds ◽  
N Transformations ◽  
Temperature And Precipitation ◽  
N Removal ◽  
In Series

Nitrogen transformations that can occur in WSP depend on pond and waste characteristics and are also influenced by climatic factors, like temperature and precipitation. Experiments described have been carried out using a system of three ponds in series: anaerobic, facultative and maturation, treating domestic sewage. In this paper we aim to identify the processes that might contribute to N transformations in each pond and the seasonal variations in the removal of nitrogen and its bioconversion throughout the year. Results have proved that there was an important organic N removal in the anaerobic pond, mainly due to mineralisation and not exclusively by sedimentation. Some of the processes of N transformation observed in the ponds were more strongly influenced by weather conditions than others. In some cases, the increase of biological activity that was induced by the increase in air temperature, was masked by reduced precipitation which produced less diluted treated effluents. These climatic factors can explain some of the variations observed along the year, in what concerns nitrogen compounds concentrations.

scholarly journals Imagining ‘Atlanta’: The Cultural Politics and Poetics of Experimental Medicine in East Africa

2014 ◽  
Vol 20 (1) ◽  
Author(s):  
Denielle Elliott
Keyword(s):  
East Africa ◽  
State Of The Art ◽  
Lake Victoria ◽  
Field Research ◽  
Experimental Medicine ◽  
Research Station ◽  
Scientific Practices ◽  
Global Science ◽  
Rural Town ◽  
The Social

In East Africa there is a field research station that locals call ‘Atlanta.’ It sits on the outskirts of a rural town, near Lake Victoria, equipped with ‘state-of-the-art’ biotechnological and entomological equipment for monitoring and exploring malaria, HIV, tuberculosis, rotavirus, and other tropical diseases. Drawn from ethnographic fieldwork with clinical trials in East Africa, this paper considers the stories people tell about the landscapes and spaces of experimental medicine to explore the uneven movement of knowledge, scientific practices, and scientists in global medicine. I begin this analytical journey at ‘Atlanta’ to consider what local idioms about such places might tell us about the encounters and travels of science and scientists in East Africa. Last, I draw attention to the social and material effects of global science projects on the lives and landscapes of East Africa.

Seasonal variations in UV-B absorbing capacity and allelopathic potential of Dittrichia viscosa leaf rinsates

1997 ◽  
Vol 75 (8) ◽  
pp. 1371-1374 ◽  
Author(s):  
M. Stephanou ◽  
Y. Manetas
Keyword(s):  
Seed Germination ◽  
Competitive Advantage ◽  
Key Words ◽  
Seasonal Variations ◽  
Water Soluble ◽  
Seasonal Fluctuations ◽  
Allelopathic Potential ◽  
Dittrichia Viscosa ◽  
The Mediterranean ◽  
Allelopathic Interference

The seasonal variations in the amount and the allelopathic potential of the water-soluble, leaf epicuticular exudates in the Mediterranean ruderal Dittrichia viscosa were investigated. Both parameters peaked during the dry, hot, and sunny summer, confirming the prediction that the seasonal fluctuations should be commensurate with the ascribed antitranspirant and phytotoxic functions. In particular, the drainage of the material to the soil with the heavy autumn rains provides excellent timing for exerting its strong allelopathic interference on seed germination, affording D. viscosa a considerable competitive advantage. Key words: allelopathy, Dittrichia viscosa, leaf rinsates, seasonal variations.

scholarly journals Spring peaks and autumn troughs identified in peripheral inflammatory markers during the peripartum period

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Hanna E. Henriksson ◽  
Richard A. White ◽  
Stavros I. Iliadis ◽  
Emma Fransson ◽  
Fotios C. Papadopoulos ◽  
...  
Keyword(s):  
Seasonal Variations ◽  
Inflammatory Markers ◽  
Inflammatory Marker ◽  
Seasonal Pattern ◽  
Cell Types ◽  
Seasonal Fluctuations ◽  
Clear Cut ◽  
Chemotactic Protein ◽  
Peripartum Period ◽  
Proximity Extension Assay

Abstract Seasonal variations have recently been described in biomarkers, cell types, and gene expression associated with the immune system, but so far no studies have been conducted among women in the peripartum period. It is of note that pregnancy complications and outcomes, as well as autoimmune diseases, have also been reported to exhibit seasonal fluctuations. We report here a clear-cut seasonal pattern of 23 inflammatory markers, analysed using proximity-extension assay technology, in pregnant women. The inflammatory markers generally peaked in the spring and had a trough in the autumn. During the postpartum period we found seasonality in one inflammatory marker, namely monocyte chemotactic protein 4 (MCP-4). Our findings suggest that seasonal variations in peripheral inflammatory markers are only observed during pregnancy. The results of this study could be valuable to professionals working within the field of immunology-related areas, and provide insight for the understanding of obstetric complications.

Seasonal variations in the component fatty acid distributions of the lipids of Balanus balanoides

1972 ◽  
Vol 52 (4) ◽  
pp. 839-845 ◽  
Author(s):  
Doris Gardner ◽  
J. P. Riley
Keyword(s):  
Fatty Acid ◽  
Seasonal Variations ◽  
Marked Decrease ◽  
Early Spring ◽  
Component Fatty Acid ◽  
Lipid Fractions ◽  
Phospholipid Ratio ◽  
June July ◽  
Food Reserves ◽  
Balanus Balanoides

A study has been made of the seasonal variations in the component acids of the lipid fractions of Balanus balanoides. The relative proportions of the polyenoic acids in the triglycerides drop sharply during the winter. They reach a minimum in the early spring and then gradually rise to a maximum in the late autumn. These changes are largely balanced by increases in the saturated acids, principally 16:0 and 18 :o.1 During the winter there is a marked decrease in the triglyceride to phospholipid ratio as the depot fats are mobilised as food reserves. The proportions of the polyethenoid acids in the phospholipids decline slowly during the winter and spring and attain their minimum in June-July. This fall is mainly counterbalanced by increases in the amounts of saturated acids, principally 14:0 and 16:0. It seems likely that the observed decreases in the polyenoic acids are brought about by selective utilization of these compounds as reserves during the winter when food is scarce and depot lipid has been depleted.

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