Seasonal changes in louse populations on white-tailed deer (Odocoileus virginianus)

1975 ◽  
Vol 53 (8) ◽  
pp. 1047-1054 ◽  
Author(s):  
Thomas G. Watson ◽  
Roy C. Anderson
Keyword(s):  
Environmental Factors ◽  
Solar Radiation ◽  
Head And Neck ◽  
Odocoileus Virginianus ◽  
Seasonal Changes ◽  
Radiation Temperature ◽  
Upper Body ◽  
Immature Stages ◽  
Body Regions ◽  
Biting Lice

The hides of 47 white-tailed deer (Odocoileus virginianus) shot at Long Point, Ontario, between September 1972 and August 1973 were examined for lice. Adult Tricholipeurus lipeuroides were most abundant from January to April and T. parallelus from May to August. The distributions of biting lice changed over the study period, possibly influenced by environmental factors such as solar radiation, temperature, rainfall, and changes in pelage. Solenopotes ferrisi was found throughout the study period. There was no significant change in abundance of the various louse stages throughout the study, although all stages were slightly more numerous during winter. Adults primarily infested the head and neck, while immature stages infested upper body regions. Changes in distribution of lice may be the result of environmental and host pelage changes.

scholarly journals Impacts of Environmental Factors on Head and Neck Cancer Pathogenesis and Progression

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 389
Author(s):  
Marisol Miranda-Galvis ◽  
Reid Loveless ◽  
Luiz Paulo Kowalski ◽  
Yong Teng
Keyword(s):  
Head And Neck Cancer ◽  
Environmental Factors ◽  
Head And Neck ◽  
Neck Cancer ◽  
Molecular Mechanisms ◽  
Metastatic Cancer ◽  
Environmental Drivers ◽  
Cancer Pathogenesis ◽  
Gene Environment ◽  
The Impact

Epidemiological and clinical studies over the past two decades have provided strong evidence that genetic elements interacting with environmental components can individually and collectively influence one’s susceptibility to cancer. In addition to tumorigenic properties, numerous environmental factors, such as nutrition, chemical carcinogens, and tobacco/alcohol consumption, possess pro-invasive and pro-metastatic cancer features. In contrast to traditional cancer treatment, modern therapeutics not only take into account an individual’s genetic makeup but also consider gene–environment interactions. The current review sharpens the focus by elaborating on the impact that environmental factors have on the pathogenesis and progression of head and neck cancer and the underlying molecular mechanisms involved. Recent advances, challenges, and future perspectives in this area of research are also discussed. Inhibiting key environmental drivers of tumor progression should yield survival benefits for patients at any stage of head and neck cancer.

Seasonal changes in the body surface temperature of Hanwoo (Bos taurus coreanae) steers

2014 ◽  
Vol 54 (9) ◽  
pp. 1476 ◽  
Author(s):  
N. Y. Kim ◽  
S. J. Kim ◽  
J. H. Park ◽  
M. R. Oh ◽  
S. Y. Jang ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Ambient Temperature ◽  
Body Surface ◽  
Seasonal Changes ◽  
Bos Taurus ◽  
The Body ◽  
Body Regions ◽  
Extreme Cold ◽  
Body Surface Temperature ◽  
Average Body

The present study aimed to gather basic information on measuring body surface temperature (BST) of cattle by using infrared thermography (IRT) and find out whether BST measurement is a useful method to detect thermal balance of livestock. Twenty-seven Hanwoo steers were examined in a field trial. The BST of five body regions (eye, nose, horn, ear, rear) was measured five times daily, with three replicates, during 3 days each season. Body surface temperature of cattle is directly affected by ambient temperature and humidity, and showed different ranges for each region. The BSTs of nose, horns and ears were significantly (P < 0.05) lower than those of eyes and rear area. Rear-area BST was significantly lower than eye-area BST when the ambient temperature was low (P < 0.05). Eye BST (EBST) was highest (P < 0.05) and the least variable of all BSTs measured. Therefore, the eye area of cattle was the most thermostable part of the body. There were significant (P < 0.05) differences among seasonal EBSTs of steers. The EBST range was highest in the summer (37.9–42.2°C), followed by autumn (34.3–37.4°C), spring (33.8–36.5°C) and winter (29.8–32.6°C). During extreme cold, EBST showed a large standard deviation. During conditions of extreme heat, EBST was above the average body temperature of cattle. The results of the present study indicated that BST well reflects the thermal circumstances surrounding animals and may be used as one of the effective tools for precision cattle farming.

scholarly journals Factors driving diversity and succession of diatom assemblages in a Neotropical rainforest stream

2018 ◽  
Vol 54 ◽  
pp. 30 ◽  
Author(s):  
Jhon Charles Donato Rondón ◽  
Yaira Ayarith Abuhatab Aragón
Keyword(s):  
Environmental Factors ◽  
Solar Radiation ◽  
Shannon Index ◽  
Diatom Assemblages ◽  
Fluvial Systems ◽  
Neotropical Streams ◽  
Biogeographic Region ◽  
Nitrate Concentrations ◽  
Taxonomic Changes ◽  
Neotropical Rainforest

This study assessed short-term succession and related changes in diversity and succession of benthic diatom assemblages in a tropical rainforest stream in the biogeographic region of Chocó, Colombia. Diatom colonization in situ was studied over a 60-day period, in which we analyzed the number of valves and the taxonomic changes. The Shannon index ranged from 2.06 to 3.02 bits. A total of 127 species were identified and the most abundant were acidophilic species such as Eunotia intermedia, E. veneris, E. bilunaris var. mucophila, E. pirla and E. bilunaris. A Detrended Canonical Correspondence Analysis (DCCA) was used to explore the succession of diatom assemblages and its driving environmental factors. The DCCA explained 74.1% of the correlation between environmental variables and diatom species and 16.2% of the data variance. The species fell into four groups, the first group (Eunotia incisa, Frustulia saxonica, Fragilaria capucina var. acatu, among others) was related to lower nitrate concentrations, acidic pH and lower water temperature. The second group (Fragilaria capensis, Gomphonema olivaceum, Cymbella gracilis, among others) was associated to higher alkalinity and lower solar radiation availability. The third group (Nitzschia obtusa, N. amphibia, Naviculadicta vitabunda, Navicula cryptocephala, among others) was related to lower phosphate, higher nitrate concentrations, lower pH, and higher temperatures. The fourth group (Eunotia soleirolli, Frustulia vulgaris and F. rhomboides) was associated with higher solar radiation and lower alkalinity. These results underscore the importance of diatom diversity in Neotropical streams and the relevance of small variations in environmental factors on the composition of reference assemblages of Neotropical fluvial systems.

scholarly journals The effect of environmental factors on the growth of alfalfa in the field.

1962 ◽  
Vol 10 (4) ◽  
pp. 247-253
Author(s):  
G. Stanhill
Keyword(s):  
Environmental Factors ◽  
Solar Radiation ◽  
Root Growth ◽  
Air Temperature ◽  
Meteorological Data ◽  
Crop Canopy

DM production from a heavily fertilized lucerne crop grown at Gilat and irrigated daily was compared with potential photosynthesis calculated from meteorological data [see F.C.A. 12: 1940]. After corrections were applied for losses due to respiration, root growth and light wasted beneath the crop canopy, calculated amounts agreed well with those measured. The percentage of light utilized was 33% with cutting at 31-day intervals and 46% with cutting at 48-day intervals. DM production was correlated positively with solar radiation and negatively with air temperature.-R.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Influence of Seasonal Environmental Variables on the Distribution of Presumptive Fecal Coliforms around an Antarctic Research Station

2003 ◽  
Vol 69 (8) ◽  
pp. 4884-4891 ◽  
Author(s):  
Kevin A. Hughes
Keyword(s):  
Environmental Factors ◽  
Solar Radiation ◽  
Sea Ice ◽  
Fecal Coliform ◽  
Algal Blooms ◽  
Austral Summer ◽  
Fecal Coliforms ◽  
Late Winter ◽  
Research Station ◽  
The Antarctic

ABSTRACT Factors affecting fecal microorganism survival and distribution in the Antarctic marine environment include solar radiation, water salinity, temperature, sea ice conditions, and fecal input by humans and local wildlife populations. This study assessed the influence of these factors on the distribution of presumptive fecal coliforms around Rothera Point, Adelaide Island, Antarctic Peninsula during the austral summer and winter of February 1999 to September 1999. Each factor had a different degree of influence depending on the time of year. In summer (February), although the station population was high, presumptive fecal coliform concentrations were low, probably due to the biologically damaging effects of solar radiation. However, summer algal blooms reduced penetration of solar radiation into the water column. By early winter (April), fecal coliform concentrations were high, due to increased fecal input by migrant wildlife, while solar radiation doses were low. By late winter (September), fecal coliform concentrations were high near the station sewage outfall, as sea ice formation limited solar radiation penetration into the sea and prevented wind-driven water circulation near the outfall. During this study, environmental factors masked the effect of station population numbers on sewage plume size. If sewage production increases throughout the Antarctic, environmental factors may become less significant and effective sewage waste management will become increasingly important. These findings highlight the need for year-round monitoring of fecal coliform distribution in Antarctic waters near research stations to produce realistic evaluations of sewage pollution persistence and dispersal.

Estimation of development times for immature stages of the bush fly, Musca vetustissima Walker (Diptera: Muscidae), and their simulation from air temperature and solar radiation records

1990 ◽  
Vol 80 (1) ◽  
pp. 73-78 ◽  
Author(s):  
W. G. Vogt ◽  
J.M. Walker ◽  
S Runko
Keyword(s):  
Solar Radiation ◽  
Air Temperature ◽  
Adult Development ◽  
Development Rate ◽  
Immature Stages ◽  
Rate Model ◽  
Development Times ◽  
Temperature Regimes ◽  
Non Linear ◽  
Constant And Fluctuating Temperature

AbstractImmature stages of bush fly, Musca vetustissima Walker, were reared at constant temperatures ranging from 18°C to 39°C. Mean egg to adult development times ranged from 7.0 to 25.8 days. Eggs, larval instars I, II and III, and pupae averaged, respectively, 3.1, 4.4, 5.5, 36.4 and 50.6% of the total development time. Mean development rate was a non-linear function of temperature. A non-linear development rate model accurately estimated mean development times of immature stages under both constant and fluctuating temperature regimes. Simulation of dung pad temperatures, from air temperature and solar radiation records, predicted development times of soil- and dunginhabiting stages of M. vetustissima to within 4% of those observed under field conditions.

Effect of environmental factors on the spatio-temporal patterns of influenza spread

2009 ◽  
Vol 137 (10) ◽  
pp. 1377-1387 ◽  
Author(s):  
K. M. L. CHARLAND ◽  
D. L. BUCKERIDGE ◽  
J. L. STURTEVANT ◽  
F. MELTON ◽  
B. Y. REIS ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Solar Radiation ◽  
Temporal Patterns ◽  
Dew Point ◽  
Bayesian Hierarchical ◽  
Influenza Activity ◽  
The Usa ◽  
Geographical Position ◽  
Spatio Temporal ◽  
Epidemic Timing

SUMMARYAlthough spatio-temporal patterns of influenza spread often suggest that environmental factors play a role, their effect on the geographical variation in the timing of annual epidemics has not been assessed. We examined the effect of solar radiation, dew point, temperature and geographical position on the city-specific timing of epidemics in the USA. Using paediatric in-patient data from hospitals in 35 cities for each influenza season in the study period 2000–2005, we determined ‘epidemic timing’ by identifying the week of peak influenza activity. For each city we calculated averages of daily climate measurements for 1 October to 31 December. Bayesian hierarchical models were used to assess the strength of association between each variable and epidemic timing. Of the climate variables only solar radiation was significantly related to epidemic timing (95% CI −0·027 to −0·0032). Future studies may elucidate biological mechanisms intrinsically linked to solar radiation that contribute to epidemic timing in temperate regions.

STUDIES ON THE ARTHROPOD FAUNA OF ALFALFA: II. ARTHROPOD–FUNGUS ASSOCIATIONS

1972 ◽  
Vol 104 (9) ◽  
pp. 1405-1412
Author(s):  
A. G. Wheeler
Keyword(s):  
Seasonal Changes ◽  
Immature Stages ◽  
Arthropod Species ◽  
Late Fall ◽  
Medicago Saliva ◽  
Arthropod Fauna

AbstractObservations were made during 1967 to 1969 at Ithaca, N.Y., supplemented by collections at New Cumberland and Carlisle, Pa., on arthropods associated with fungi occurring on alfalfa, Medicago saliva L. Five species of Coleoptera, two species of Diptera, one species each of Collembola and Psocoptera, and nine species of Acari were reared or collected consistently from fungus-covered alfalfa leaves, stems, and seed pods. Attraction to fungi on the plants, principally Alternaria sp., accounted for the presence on alfalfa of arthropod species that normally might be considered as accidentals or visitors. The mycetophagous species thus contributed to the richness of the alfalfa fauna. Immature stages of several species were collected only in late fall or on 3- or 4-year-old plants. The possible role of the fungus-feeding species in seasonal changes in the alfalfa fauna and changes in the fauna in successive years is discussed.

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