EFFECT OF TRAP SITE, TIME OF DAY, AND METEOROLOGICAL FACTORS ON ABUNDANCE OF HOST-SEEKING MAMMALOPHILIC BLACK FLIES (DIPTERA: SIMULIIDAE)

1994 ◽  
Vol 126 (2) ◽  
pp. 283-289 ◽  
Author(s):  
Francis R. Martin ◽  
J.W. McCreadie ◽  
M.H. Colbo
Keyword(s):  
Meteorological Factors ◽  
Time Of Day ◽  
Sticky Trap ◽  
Black Flies ◽  
Trap Site ◽  
Saturation Deficit ◽  
Host Seeking ◽  
Trap Location ◽  
The Mean ◽  
Trapping Location

AbstractSweep-net and sticky-trap data were used to examine the influence of time of day (morning, afternoon, evening), trapping location (pasture, bog, fen, regrowth, and mature forest), and meteorological factors (wind, temperature, saturation deficit, and light) on adult female fly catch for three species (species complex) of black flies — Simulium truncatum/venustum complex, Prosimulium mixtum, and Stegopterna mutata (triploid). Wind speed, light, temperature, saturation deficit, and time of day were all shown to have a significant effect on mean catch, although effects varied among species. After accounting for weather and time, trap location was shown to have a significant effect on mean catch. The effect of site on the mean fly catch of S. truncatum/venustum complex varied with season (June to July), which may have resulted from a seasonal shift in sibling-species composition. Mean catches of P. mixtum and St. mutata were lowest in traps located in open habitats.

Thermoregulatory responses to cold water at different times of day

1999 ◽  
Vol 87 (1) ◽  
pp. 243-246 ◽  
Author(s):  
John W. Castellani ◽  
Andrew J. Young ◽  
James E. Kain ◽  
Michael N. Sawka
Keyword(s):  
Cold Water ◽  
Water Immersion ◽  
Early Morning ◽  
Cold Water Immersion ◽  
Time Of Day ◽  
Mean Skin Temperature ◽  
Mean Body Temperature ◽  
Metabolic Heat ◽  
Body Temperature Change ◽  
The Mean

This study examined how time of day affects thermoregulation during cold-water immersion (CWI). It was hypothesized that the shivering and vasoconstrictor responses to CWI would differ at 0700 vs. 1500 because of lower initial core temperatures (Tcore) at 0700. Nine men were immersed (20°C, 2 h) at 0700 and 1500 on 2 days. No differences ( P > 0.05) between times were observed for metabolic heat production (M˙, 150 W ⋅ m−2), heat flow (250 W ⋅ m−2), mean skin temperature (T sk, 21°C), and the mean body temperature-change in M˙(ΔM˙) relationship. Rectal temperature (Tre) was higher ( P < 0.05) before (Δ = 0.4°C) and throughout CWI during 1500. The change in Tre was greater ( P < 0.05) at 1500 (−1.4°C) vs. 0700 (−1.2°C), likely because of the higher Tre-T skgradient (0.3°C) at 1500. These data indicate that shivering and vasoconstriction are not affected by time of day. These observations raise the possibility that CWI may increase the risk of hypothermia in the early morning because of a lower initial Tcore.

Twenty-four-hour rhythms of plasma glucose and insulin secretion rate in regular night workers

2000 ◽  
Vol 278 (3) ◽  
pp. E413-E420 ◽  
Author(s):  
C. Simon ◽  
L. Weibel ◽  
G. Brandenberger
Keyword(s):  
Insulin Secretion ◽  
Mean Amplitude ◽  
Sampling Procedure ◽  
Time Of Day ◽  
Secretion Rate ◽  
Nocturnal Sleep ◽  
Sleep Condition ◽  
The Mean ◽  
Nighttime Sleep ◽  
Insulin Secretion Rate

To determine whether the ultradian and circadian rhythms of glucose and insulin secretion rate (ISR) are adapted to their permanent nocturnal schedule, eight night workers were studied during their usual 24-h cycle with continuous enteral nutrition and a 10-min blood sampling procedure and were compared with 8 day-active subjects studied once with nocturnal sleep and once with an acute 8-h-shifted sleep. The mean 24-h glucose and ISR levels were similar in the three experiments. The duration and the number of the ultradian oscillations were influenced neither by the time of day nor by the sleep condition or its shift, but their mean amplitude increased during sleep whenever it occurred. In day-active subjects, glucose and ISR levels were high during nighttime sleep and then decreased to a minimum in the afternoon. After the acute sleep shift, the glucose and ISR rhythms were split in a biphasic pattern with a slight increase during the night of deprivation and another during daytime sleep. In night workers, the glucose and ISR peak levels exhibited an 8-h shift in accordance with the sleep shift, but the onset of the glucose rise underwent a shift of only 6 h and the sleep-related amplification of the glucose and ISR oscillations did not occur simultaneously. These results demonstrate that despite a predominant influence of sleep, the 24-h glucose and ISR rhythms are only partially adapted in permanent night workers.

scholarly journals Assessment of intraocular pressure in chinchillas of different age groups using rebound tonometry

2016 ◽  
Vol 46 (8) ◽  
pp. 1466-1471 ◽  
Author(s):  
Flor Diana Yokoay Claros Chacaltana ◽  
João Antonio Tadeu Pigatto ◽  
Ione Terezinha Denardin
Keyword(s):  
Intraocular Pressure ◽  
Age Groups ◽  
Time Of Day ◽  
Age Group ◽  
Group Iii ◽  
Rebound Tonometer ◽  
Indirect Ophthalmoscopy ◽  
Group I ◽  
Schirmer Tear Test ◽  
The Mean

ABSTRACT: The aim of this research was to measure the intraocular pressure (IOP) of normal chinchilla eyes using the rebound tonometer. A further aim was to assess whether there were differences in the values of intraocular pressure in relation to animals age, gender and time of day. Thirty-six chinchillas were divided into three groups of 12 chinchillas each, by age: Group I (2-6-month-old), Group II (20 and 34 months) and Group III (37 and 135 months). Ophthalmic examination was performed previously by Schirmer tear test, slit lamp biomicroscopy, indirect ophthalmoscopy and fluorescein test in all chinchillas. Three measurements of intraocular pressure were assessed on the same day (7, 12 and 19h). Tonometry was performed on both eyes using the rebound tonometer after calibration in "p" mode. Statistical analysis was performed with SigmaPlot for Windows. The mean IOP for groups I, II and III were 2.47±0.581mmHg, 2.47±0.581mmHg and 2.51±0.531mmHg, respectively. No significant differences were reported between age and IOP and no significant differences were reported between the time of day and IOP. The IOP in chinchillas did not differ significantly between genders or ages of the animals, and did not change with time of day.

scholarly journals Scale Characterization and Correction of Diurnal Cycle Errors in MAPLE

2017 ◽  
Vol 56 (9) ◽  
pp. 2561-2575 ◽  
Author(s):  
Aitor Atencia ◽  
Isztar Zawadzki ◽  
Marc Berenguer
Keyword(s):  
Diurnal Cycle ◽  
Spatial Scales ◽  
Time Of Day ◽  
Precipitation Forecast ◽  
Systematic Bias ◽  
Correction Scheme ◽  
Average Rainfall ◽  
The Mean ◽  
Scale Characterization ◽  
Composite Data

AbstractThe most widely used technique for nowcasting of quantitative precipitation in operational and research centers is the Lagrangian extrapolation of the latest radar observations. However, this technique has a limited forecast skill because of the assumption made on its formulation, such as the fact that the motion vectors do not change and, even more important for convective events, neglect any growth or decay in the precipitation field. In this work, the McGill Algorithm for Precipitation Nowcasting by Lagrangian Extrapolation (MAPLE) errors have been computed for 10 yr of radar composite data over the continental United States. The study of these errors shows systematic bias depending on the time of day. This effect is related to the solar cycle, whose heating energy results in an increase in the average rainfall in the afternoon. This external forcing interacts with the atmospheric system, creating local initiation and dissipation of convection depending on orography, land use, cloud coverage, etc. The signal of the diurnal cycle in MAPLE precipitation forecast has been studied in different locations and spatial scales as a function of lead time in order to recognize where, when, and for which spatial scales the signal is significant. This information has been used in the development of a scaling correction scheme where the mean errors due to the diurnal cycle are adjusted. The results show that the developed methodology improves the forecast for the spatial scales and locations where the diurnal cycle signal is significant.

scholarly journals Seasonal activity of Dermacentor reticulatus ticks in the era of progressive climate change in eastern Poland

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zbigniew Zając ◽  
Joanna Kulisz ◽  
Aneta Woźniak ◽  
Katarzyna Bartosik ◽  
Adil Khan
Keyword(s):  
Climate Change ◽  
Local Population ◽  
Weather Conditions ◽  
Dermacentor Reticulatus ◽  
Seasonal Activity ◽  
Saturation Deficit ◽  
Annual Basis ◽  
Questing Ticks ◽  
The Mean

AbstractDermacentor reticulatus ticks are one of the most important vectors and reservoirs of tick-borne pathogens in Europe. Changes in the abundance and range of this species have been observed in the last decade and these ticks are collected in areas previously considered tick-free. This may be influenced by progressive climate change. Eastern Poland is an area where the local population of D. reticulatus is one of the most numerous among those described so far. At the same time, the region is characterized by a significant increase in the mean air temperature in recent years (by 1.81 °C in 2020) and a decrease in the average number of days with snow cover (by 64 days in 2020) and in the number of days with frost (by 20 days in 2020) on an annual basis compared to the long-term average. The aim of our research was to investigate the rhythms of seasonal activity and the population size of D. reticulatus in the era of progressive climate change. To this end, questing ticks were collected in 2017–2020. Next, the weather conditions in the years of observation were analyzed and compared with multi-year data covering 30 years preceding the study. The research results show that, in eastern Poland, there is a stable population of D. reticulatus with the peak of activity in spring or autumn (up to a maximum of 359 individuals within 30 min of collection) depending on the year of observation. Ticks of this species may also be active in winter months. The activity of D. reticulatus is influenced by a saturation deficit.

scholarly journals Comparative verification in complex topography

2021 ◽  
Author(s):  
Jonas Bhend ◽  
Jean-Christophe Orain ◽  
Vera Schönenberger ◽  
Christoph Spirig ◽  
Lionel Moret ◽  
...  
Keyword(s):  
Weather Forecasting ◽  
Absolute Error ◽  
Time Of Day ◽  
Probabilistic Forecasts ◽  
Wide Range ◽  
Direct Model ◽  
Forecasting System ◽  
The Mean ◽  
Update Frequency ◽  
Core Activity

&lt;p&gt;Verification is a core activity in weather forecasting. Insights from verification are used for monitoring, for reporting, to support and motivate development of the forecasting system, and to allow users to maximize forecast value. Due to the broad range of applications for which verification provides valuable input, the range of questions one would like to answer can be very large. Static analyses and summary verification results are often insufficient to cover this broad range. To this end, we developed an interactive verification platform at MeteoSwiss that allows users to inspect verification results from a wide range of angles to find answers to their specific questions.&lt;/p&gt;&lt;p&gt;We present the technical setup to achieve a flexible yet performant interactive platform and two prototype applications: monitoring of direct model output from operational NWP systems and understanding of the capabilities and limitations of our pre-operational postprocessing. We present two innovations that illustrate the user-oriented approach to comparative verification adopted as part of the platform. To facilitate the comparison of a broad range of forecasts issued with varying update frequency, we rely on the concept of time of verification to collocate the most recent available forecasts at the time of day at which the forecasts are used. In addition, we offer a matrix selection to more flexibly select forecast sources and scores for comparison. Doing so, we can for example compare the mean absolute error (MAE) for deterministic forecasts to the MAE and continuous ranked probability scores of probabilistic forecasts to illustrate the benefit of using probabilistic forecasts.&lt;/p&gt;

scholarly journals Diet of the Nestling Tree Swallow

The Condor ◽  
2004 ◽  
Vol 106 (2) ◽  
pp. 423-429 ◽  
Author(s):  
Jean M. Mengelkoch ◽  
Gerald J. Niemi ◽  
Ronald R. Regal
Keyword(s):  
Open Water ◽  
Time Of Day ◽  
Tachycineta Bicolor ◽  
Tree Swallow ◽  
Tree Swallows ◽  
Larval Stages ◽  
Terrestrial Origin ◽  
The Mean ◽  
Foraging Radius

Abstract Dietary samples from nestling Tree Swallows (Tachycineta bicolor) in northwestern Minnesota were compared to invertebrate availability as measured by aerial tow nets. The majority of the biomass in the nestlings' diet was adult insects with larval stages of aquatic origin, while absolute numbers of insects of both aquatic and terrestrial origin were similar. Orders of invertebrates in the diet and available were similar in number but not in biomass. Diet showed little variation by time of day, date of sampling or the age of the nestling. The mean number of odonates in the nestling Tree Swallows' diet increased exponentially as the percentage of open water and open water + cattail marsh increased within a 400-m foraging radius. Dieta de los Pichones de Tachycineta bicolor Resumen. Se compararon muestras dietarias de pichones de la golondrina Tachycineta bicolor tomadas en el noroeste de Minnesota con la disponibilidad de invertebrados medida con redes aéreas. La mayor parte de la biomasa en la dieta de los pichones correspondió a insectos adultos con estadíos larvales de origen acuá tico, mientras que los números absolutos de insectos de origen acuático y no acuático fueron similares. Los órdenes de invertebrados presentes en la dieta y disponibles en el ambiente fueron similares en números pero no en biomasa. La dieta mostró poca variación entre horas del día, fechas de muestreo o edad de los pichones. El número promedio de odonatos en la dieta de los pichones de T. bicolor aumentó exponencialmente a medida que se incrementó el porcentaje de agua abierta y de agua abierta + pantanos de espadañas dentro de un radio de forrajeo de 400 m.

HOURLY FLUCTUATIONS IN THE BLOOD LEVELS OF MELATONIN, PROLACTIN, LUTEINIZING HORMONE, FOLLICLE-STIMULATING HORMONE, TESTOSTERONE, TRI-IODOTHYRONINE, THYROXINE AND CORTISOL IN RAMS UNDER ARTIFICIAL PHOTOPERIODS, AND THE EFFECTS OF CRANIAL SYMPATHECTOMY

1982 ◽  
Vol 92 (2) ◽  
pp. 237-250 ◽  
Author(s):  
G. A. LINCOLN ◽  
O. F. X. ALMEIDA ◽  
H. KLANDORF ◽  
R. A. CUNNINGHAM
Keyword(s):  
Follicle Stimulating Hormone ◽  
Time Of Day ◽  
Blood Levels ◽  
Blood Concentrations ◽  
Blood Samples ◽  
Mean Values ◽  
Change In The Mean ◽  
The Mean ◽  
Cervical Ganglia ◽  
Short Days

Eight adult Soay rams (four control and four cranially sympathectomized by removal of the superior cervical ganglia) were exposed to alternating 16-week periods of short days of 8 h light: 16 h darkness (8L : 16D) and long days (16L : 8D) for more than 3 years, and the changes in the diameter of the testes were recorded. Once during short days and once during long days blood samples were collected hourly for 28 h, and the concentrations of melatonin, prolactin, FSH, LH, testosterone, tri-iodothyronine (T3), thyroxine (T4) and cortisol were measured by radioimmunoassay. In the control rams the testes were reduced in size during long days compared to short days, and the blood concentrations (24-h mean values) of FSH, LH and testosterone were decreased. The levels of prolactin were much increased, while there was no significant change in the mean levels of melatonin, T3, T4 and cortisol. During both photoperiods there was considerable hour-to-hour variation in all eight hormones indicative of episodic secretion, as well as a consistent variation related to the time of day which was most pronounced for melatonin and T3. There was a clear difference in the daily profile of plasma melatonin levels between short and long days. In the superior cervical ganglionectomized rams there were no significant changes in the size of the testes or in the hormone titres between short and long days. Compared to the controls the plasma levels of LH, FSH, testosterone and prolactin were in the intermediate range. Some consistent diurnal variation was evident in the levels of all the hormones measured, with a pattern similar to the controls for a few of the hormones (e.g. T3) but quite different for others (e.g. melatonin).

Some sources of error and possible bias in Danscan ultrasonic measurements of cattle

1983 ◽  
Vol 37 (1) ◽  
pp. 67-71
Author(s):  
J. P. Gibson ◽  
J. C. Alliston
Keyword(s):  
Measurement Error ◽  
Mean Value ◽  
Time Of Day ◽  
Error Distribution ◽  
The Body ◽  
Residual Error ◽  
Ultrasonic Measurements ◽  
The Mean ◽  
Ultrasonic Images ◽  
Account Variation

ABSTRACTPhotographs of ultrasonic images of 10 animals were taken. Two replicate photographs were taken at each of four body positions (10th rib, 13th rib, 3rd lumbar and hindquarter) on both sides of the body in the morning and the afternoon of the day of scanning. Several measurements were taken on each photograph by an experienced interpreter. Replicate photographs failed to account for all possible sources of measurement error. Since neither time of day nor side of the body affected the mean value, taking observations at different times of the day or on both sides of the body could permit most sources of measurement error to be taken into account. Variation due to errors of measurement and differences among animals are presented. The residual error distribution contained several extreme outliers.It was concluded that a better understanding of all the sources of bias and error will be needed if ultrasonic measurements are to be more widely used.

THE POPULATION AND ACTIVITY OF ADULT FEMALE BLACK FLIES IN THE VICINITY OF A STREAM IN ALGONQUIN PARK, ONTARIO

1952 ◽  
Vol 30 (5) ◽  
pp. 287-321 ◽  
Author(s):  
Douglas M. Davies
Keyword(s):  
Human Skin ◽  
Adult Female ◽  
Unit Area ◽  
Meteorological Factors ◽  
Black Flies ◽  
Direct Sunlight ◽  
Large Peak

The population of females of Simulium venustum Say on the wing was measured by hand-netting. The population varied annually and seasonally coincident with the number and longevity of immigrant and emergent flies. Longevity in turn was probably related to the rainfall.Activity was divided into flying, attraction, landing, and biting, the first two measured by hand-netting and the last two by counts on a unit area of human skin in the shade. Flying usually varied diurnally, a large peak in the evening and a small one in the morning. Attraction varied with none of the meteorological factors measured. Biting and flying increased and landing decreased with rapidly changing, especially falling, pressure. Other factors influenced flying and landing, but not biting, when the area was in the shade. Flying was greatest between 60–80° F., at low but not zero saturation deficiencies, in light winds, and in zero to low rates of evaporation. Landing on the host was least below 55 °F. and at 65–75 °F., at zero and intermediate saturation deficiencies, and at moderately high rates of evaporation. These factors affected the flies landing on the host directly, and indirectly by curtailing the flying that brought flies to the host in the first place. In the direct sunlight landing decreased to one-half and biting; to one-quarter of that in the shade.

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