Some Factors Affecting Flight Activity in Individual Milkweed Bugs (Oncopeltus)

1966 ◽  
Vol 44 (2) ◽  
pp. 335-343
Author(s):  
HUGH DINGLE
Keyword(s):  
Total Duration ◽  
Flight Activity ◽  
Peak Activity ◽  
Growth Rings ◽  
Peak Period ◽  
Flight Duration ◽  
Factors Affecting ◽  
Continuous Contact ◽  
Tethered Flight ◽  
Opposite Sex

1. Individual adults of Oncopeltus were tested repeatedly at 2- or 3-day intervals, using tethered flight, to determine the amount of flight activity as measured by flight duration. 2. The peak period of activity occurred 8 days after the final moult with later flights scattered and showing no concentration at a particular age. Deposition of cuticular growth rings ceased at about 7 days; the peak activity was thus post-teneral and probably represents migration. 3. Only 23.8% of bugs tested showed flights of over 30 min. Those bugs which flew for long periods at 8 days were more likely to show long flights at a later age than were bugs which did not fly at day 8. There thus seems to be a behavioural polymorphism with distinct ‘flyers’ and ‘non-flyers’. 4. More females, 30.7%, than males, 18.1%, exhibited flights of over 30 minutes. Males which did have such long flights were, however, more likely than females to have them repeatedly. 5. In both sexes virgins seemed to be more active in respect of long flights than bugs allowed continuous contact with the opposite sex. 6. Calculations based on estimates of flight speed and total duration of flight indicate that an individual migrant Oncopeltus is capable of covering a considerable distance, 100 kilometres or more, during its lifetime.

scholarly journals Quantifying flight aptitude variation in wild A. gambiae s.l. in order to identify long-distance migrants

2020 ◽  
Author(s):  
Roy Faiman ◽  
Alpha Seydou YARO ◽  
Moussa Diallo ◽  
Adama Dao ◽  
Djibril Samake ◽  
...  
Keyword(s):  
Sensu Stricto ◽  
Flight Activity ◽  
Malaria Vectors ◽  
Anopheles Coluzzii ◽  
Wing Size ◽  
Wet Season ◽  
Long Distance ◽  
Flight Duration ◽  
Tethered Flight ◽  
Gravid Females

Abstract Background In the West African Sahel, mosquito reproduction is halted during the 5-7 month-long dry season, due to the absence of surface waters required for larval development. However, recent studies have suggested that both Anopheles gambiae sensu stricto (s.s.) and Anopheles arabiensis repopulate this region via migration from distant locations where larval sites are perennial. Anopheles coluzzii engages in more regional migration, presumably within the Sahel, following shifting resources correlating with the ever-changing patterns of Sahelian rainfall. Understanding mosquito migration is key to controlling malaria—a disease that continues to claim more than 400,000 lives annually, especially those of African children. Using tethered flight data of wild mosquitoes, the distribution of flight parameters were evaluated as indicators of long-range migrants versus appetitive flyers, and the species specific seasonal differences and gonotrophic states compared between two flight activity modalities. Morphometrical differences were evaluated in the wings of mosquitoes exhibiting high flight activity (HFA) vs. low flight activity (LFA).Methods A novel tethered-flight assay was used to characterize flight in the three primary malaria vectors- An. arabiensis, An. coluzzii and An. gambiae s.s. The flights of tethered wild mosquitoes were audio-recorded from 21:00h to 05:00h in the following morning and three flight aptitude indices were examined: total flight duration, longest flight bout, and the number of flight bouts during the assay.Results The distributions of all flight indices were strongly skewed to the right, indicating that the population consisted of a majority of low-flight activity (LFA) mosquitoes and a minority of high-flight activity (HFA) mosquitoes. The median total flight was 586 seconds and the maximum value was 16,110 seconds (~4.5 h). In accordance with recent results, flight aptitude peaked in the wet season, and was higher in gravid females than in non-blood-fed females. Flight aptitude was also found to be higher in An. coluzzii compared to An. arabiensis, with intermediate values in An. gambiae s.s., but displaying no statistical difference. Evaluating differences in wing size and shape between LFA individuals and HFA ones, the wing size of HFA An. coluzzii was larger than that of LFAs during the wet season—its length was wider than predicted by allometry alone, indicating a change in wing shape. No statistically significant differences were found in the wing size/shape of An. gambiae s.s. or An. arabiensis.Conclusions The partial agreement between the tethered flight results and recent results based on aerial sampling of these species suggest a degree of discrimination between appetitive flyers and long-distance migrants although identifying HFAs as long-distance migrants is not recommended without further investigation.

scholarly journals Quantifying flight aptitude variation in wild An. gambiae s.l. in order to identify long-distance migrants

2020 ◽  
Author(s):  
Roy Faiman ◽  
Alpha Seydou YARO ◽  
Moussa Diallo ◽  
Adama Dao ◽  
Djibril Samake ◽  
...  
Keyword(s):  
Flight Activity ◽  
Malaria Vectors ◽  
Wing Size ◽  
Wet Season ◽  
Long Distance ◽  
Flight Duration ◽  
Tethered Flight ◽  
Gravid Females ◽  
Species Specific ◽  
The Right

Abstract Background In the West African Sahel, mosquito reproduction is halted during the 5-7 month-long dry season, due to the absence of surface waters required for larval development. However, recent studies have suggested that both Anopheles gambiae s.s and An. arabiensis repopulate this region via migration from distant locations where larval sites are perennial. An. coluzzii engages in more regional migration, presumably within the Sahel, following shifting resources correlating with the ever-changing patterns of Sahelian rainfall. Understanding mosquito migration is key to controlling malaria—a disease that continues to claim more than 400,000 lives annually, especially those of African children. Using tethered flight data of wild mosquitoes, we evaluated the distribution of flight parameters as indicators of long-range migrants vs. appetitive flyers, compared species specific seasonal differences and gonotrophic states on flight activity. We also evaluated morphometrical differences in the wings of mosquitoes exhibiting high flight activity (HFA) vs. low flight activity (LFA). Methods We used a novel tethered-flight assay to characterize flight in the three primary malaria vectors- An. arabiensis, An. coluzzii and An. gambiae s.s. The flights of tethered wild mosquitoes were audio-recorded from 21:00h to 05:00h in the following morning and three flight aptitude indices were examined: total flight duration, longest flight bout, and the number of flight bouts during the assay. Results The distributions of all flight indices were strongly skewed to the right, indicating that the population consisted of a majority of low-flight activity (LFA) mosquitoes and a minority of high-flight activity (HFA) mosquitoes. The median total flight was 586 seconds and the maximum value was 16,110 seconds (~4.5 h). In accordance with recent results, flight aptitude peaked in the wet season, and was higher in gravid females than in non-bloodfed females. Flight aptitude was also found to be higher in An. coluzzii compared to An. arabiensis, with intermediate values in An. gambiae s.s., but displaying no statistical difference. Evaluating differences in wing size and shape between LFA individuals and HFA ones, the wing size of HFA An. coluzzii was larger than that of LFAs during the wet season—its length was wider than predicted by allometry alone, indicating a change in wing shape. No statistically significant differences were found in the wing size/shape of An. gambiae s.s. or An. arabiensis. Conclusions The partial agreement between the tethered flight results and recent results based on aerial sampling of these species suggest a degree of discrimination between appetitive flyers and long-distance migrants although identifying HFAs as long-distance migrants is not recommended without further investigation.

Prevalence and Course of Schizophrenia in a Chinese Rural Area

2003 ◽  
Vol 37 (4) ◽  
pp. 452-457 ◽  
Author(s):  
Mao-Sheng Ran ◽  
Meng-Ze Xiang ◽  
Sheng-Xian Li ◽  
You-He Shan ◽  
Ming-Sheng Huang ◽  
...  
Keyword(s):  
Rural Area ◽  
Clinical Course ◽  
Age Of Onset ◽  
Total Duration ◽  
Community Based ◽  
Factors Affecting ◽  
Total Prevalence ◽  
Duration Of Illness ◽  
Family Economy ◽  
The Status

Objective: To assess the characteristics and factors affecting course of schizophrenia in a Chinese rural area. Method: An epidemiological investigation was conducted to identify all the patients with schizophrenia among 149 231 people in Xinjin County, Chengdu. Results: The total prevalence of schizophrenia was 4.13 per 1000 population. Males had an earlier mean age of onset (29.6 years) than females (32.3 years). Duration of illness before treatment and the total duration of illness were found to be significantly associated with level of remission. The status of treatment, family economy, housing, and families' care of patients had a significant effect on the clinical course of the illness. Conclusions: Duration of illness before treatment may be an important predictor of course in schizophrenia. Early treatment for the patients may produce higher level of improvement in prognosis. Education intervention and community-based service are urgent priorities for these patients.

Experimental Investigation of Ventilation Effectiveness in an Airliner Cabin Mockup

2016 ◽  
Author(s):  
Jignesh A. Patel ◽  
Byron W. Jones ◽  
Mohammad H. Hosni ◽  
Ali Keshavarz
Keyword(s):  
Distribution System ◽  
Ventilation Rate ◽  
Mean Value ◽  
Tracer Gas ◽  
Flight Duration ◽  
Factors Affecting ◽  
Aircraft Cabin ◽  
Local Ventilation ◽  
Effective Ventilation ◽  
Ventilation Effectiveness

Frequent air travel and long flight duration makes the study of airliner cabin environmental quality a topic of utmost importance. Ventilation effectiveness is one of the more crucial factors affecting air quality in any environment. Ventilation effectiveness, along with the overall ventilation rate, is a measure of the ability of the air distribution system to remove internally generated pollutants or contaminants from a given space. Because of the high occupant density in an aircraft cabin, local variations in ventilation are important as a passenger will occupy the same space for the duration of the flight. Poor ventilation in even a small portion of the cabin could impact multiple people for extended time periods. In this study, the local effective ventilation rates and local ventilation effectiveness in an eleven-row, full-scale, Boeing 767 cabin mockup were measured. These measurements were completed at each of the 77 seats in the mockup. Each seat was occupied by a heated mannequin. In order to simulate the thermal load inside the cabin, the mannequins were wrapped with a heating wire to generate approximately 100 W (341 BTU/hour) of heat. Carbon dioxide was used as a tracer gas for the experiments and the tracer gas decay method was employed to calculate the local effective ventilation rate and local ventilation effectiveness. The overall ventilation rate, based on total supply air flow, was approximately 27 air changes per hour. Local ventilation effectiveness ranged from 0.86 to 1.02 with a mean value of 0.94. These ventilation effectiveness values are higher than typically found in other indoor applications and are likely due to the relatively high airspeeds present in the aircraft cabin and the high degree of mixing they provide. The uniformity is also good with no areas of particularly low ventilation effectiveness being identified. No clear patterns with respect to seat location, window versus center versus aisle, were found.

OBSERVATIONS, MONITORING, AND CONTROL OF CLEARWING BORERS (LEPIDOPTERA: SESIIDAE) ON APPLE IN CENTRAL ONTARIO

1985 ◽  
Vol 117 (12) ◽  
pp. 1471-1478 ◽  
Author(s):  
J. Warner ◽  
S. Hay
Keyword(s):  
Malus Domestica ◽  
Flight Activity ◽  
Larval Feeding ◽  
Peak Activity ◽  
Monitoring And Control ◽  
Apple Rootstocks ◽  
Synanthedon Scitula ◽  
And Control ◽  
Dogwood Borer

AbstractObservations on Malus domestica (Borkh) in central Ontario between 1981 and 1984 revealed that dogwood borer (Synanthedon scitula Harris) larval feeding was primarily associated with burr knots on the above-ground portion of apple rootstocks. Trunk injuries also served as sites of entry. Monitoring with pheromones indicated moth emergence occurred from late June until early August with peak activity occurring near the middle of July. Control of the dogwood borer on apple was obtained with 2 trunk drench sprays of dimethoate, fenvalerate, permethrin plus oil, endosulfan, parathion, chlorpyrifos, or lindane when applied during the period of adult flight activity.

scholarly journals Get Up and Go: Evaluating Station Area Factors affecting A.M. Commuter Rail Boardings in the Greater Toronto and Hamilton Area

2021 ◽  
Author(s):  
Graham Lee Procter
Keyword(s):  
Regression Models ◽  
Land Use Policy ◽  
Peak Period ◽  
Cross Sectional ◽  
Priority List ◽  
Factors Affecting ◽  
Commuter Rail ◽  
Built Form ◽  
Time Period ◽  
Household Density

This research evaluates built form and demographic factors of GO Transit commuter rail station areas that contribute to ridership and utilization of existing services in the A.M. peak period using biannual GO Rail ridership information from the Spring of 2010 to Spring of 2015. In order to identify predictors of ridership growth, four regression models were estimated that evaluated factors affecting cross-sectional ridership, cross-sectional utilization of capacity, station-level utilization at each time period, and station-level year-over-year utilization growth. Results indicate that the strongest predictors of ridership, utilization, and growth were station parking capacity and household density of the surrounding area. This suggests potential for tensions in developing GO-supportive station-area land use policy strategies focused on either expanding station-area parking capacity or station-area residential intensification. The station level utilization model produced a priority list of future service increases on GO Rail corridors based on existing capacity and ridership.

scholarly journals Quantifying flight aptitude variation in wild A. gambiae s.l. in order to identify long-distance migrants

2020 ◽  
Author(s):  
Roy Faiman ◽  
Alpha Seydou YARO ◽  
Moussa Diallo ◽  
Adama Dao ◽  
Djibril Samake ◽  
...  
Keyword(s):  
Shape Change ◽  
Flight Activity ◽  
Malaria Vectors ◽  
Wing Size ◽  
Wet Season ◽  
Anopheles Gambiae S.S ◽  
Long Distance ◽  
Flight Duration ◽  
Size And Shape ◽  
Gravid Females

Abstract Background In the West African Sahel, during the 5-7 month-long dry season mosquito reproduction is halted due to the absence of surface waters required for larval development. Recent studies have suggested that both Anopheles gambiae s.s and A. arabiensis persist in this region by migration from distant locations where larval sites are perennial, and A. coluzzii engages in long-distance migration, presumably within the Sahel, following shifting resources due to the ever-changing patterns of Sahelian rainfall. Understanding mosquito migration is key to malaria control, a disease that still kills >400,000 people, mostly children in Africa. Methods We used a new tethered-flight assay to characterize flight in the three primary malaria vectors mentioned above and evaluated seasonal differences in their flight activity. The flight of tethered wild mosquitoes was audio-recorded from 21:00h to 05:00h in the following morning and three flight aptitude indices were examined: total flight duration, longest flight bout, and the number of flight bouts during the assay. Based on recent studies, we predicted that (i) the distribution of the flight aptitude indices would exhibit bi-modality and/or marked skewness, indicating a subpopulation of high flight activity (HFA) associated with long-distance migrants, in contrast to low flight activity (LFA) in appetitive flyers. Additionally, flight aptitude would (ii) increase in the wet season, (iii) increase in gravid females, and (iv) vary among the vector species. ResultsThe distributions of all flight indices departed sharply from a normal curve, and were strongly skewed to the right, consistent with the division of the population into a majority of LFAs and a minority of HFAs, e.g., the median total flight was 586 seconds, and its maximum value was 16,110 seconds (~4.5 h). As predicted, flight aptitude peaked in the wet season and was higher in gravid females than in non-bloodfed females. Flight aptitude was higher in A. coluzzii than in A. arabiensis, but A. gambiae s.s. was not statistically different from either. We evaluated differences in wing size and shape between LFAs and HFAs. During the wet season, wing size of HFA A. coluzzii was larger than that of LFAs; it was wider than predicted by its length, indicating a shape change. However, no statistically significant differences were found in wings of A. gambiae s.s. or A. arabiensis. ConclusionsThe partial agreement between the assay results and predictions suggest a degree of discrimination between appetitive flyers and long-distance migrants. Wing size and shape seems to indicate higher flight activity in A. coluzzii during the wet season.

Hypothalamic, rectal, and muscle temperatures in exercising dogs: effect of cooling

1985 ◽  
Vol 58 (5) ◽  
pp. 1444-1448 ◽  
Author(s):  
B. Kruk ◽  
H. Kaciuba-Uscilko ◽  
K. Nazar ◽  
J. E. Greenleaf ◽  
S. Kozlowski
Keyword(s):  
Treadmill Exercise ◽  
Total Duration ◽  
Plasma Osmolality ◽  
Exercise Duration ◽  
Lactic Acid Concentration ◽  
Working Ability ◽  
Factors Affecting ◽  
External Cooling ◽  
Series Of Experiments ◽  
Body Cooling

To investigate mechanisms that may be involved in the prolongation of exercise performance with body cooling hypothalamic (Thy), rectal (Tre), and exercising muscle (Tm) temperatures, as well as the heart rate, respiratory rate, blood lactic acid concentration ( [LA] ), and plasma osmolality (Osm) were measured in five dogs during exhaustive treadmill exercise at an ambient temperature (Ta) of 22 +/- 1 degree C without cooling (control) and with external cooling by use of ice packs. In both series of experiments, dehydration of animals was prevented. Compared with exercise with noncooling, exercise with cooling resulted in 1) increased exercise duration from 90 +/- 14 to 145 +/- 15 min (62%, P less than 0.05); 2) attenuated increases in Thy, Tre, and Tm; 3) decreased respiratory and heart rates; and 4) lowered LA. Significant negative correlations were found between both Tm and delta Tm attained at 60 min of the run and time of exercise until exhaustion (r = -0.72 and -0.74, respectively; P less than 0.02). This work failed to differentiate clearly changes or equilibrium levels of brain, core, or muscle temperature as separate factors affecting work tolerance. However, the inverse relationship between Tm reached at 60 min of the run (in both experiments) and the total duration of exercise indicates that sustained muscle hyperthermia may largely contribute to limitation of working ability.

The Factors Affecting Airspace Capacity in Europe: A Cross-Sectional Time-Series Analysis Using Simulated Controller Workload Data

2004 ◽  
Vol 57 (3) ◽  
pp. 385-405 ◽  
Author(s):  
Arnab Majumdar ◽  
Washington Y. Ochieng ◽  
Gérard McAuley ◽  
Jean Michel Lenzi ◽  
Catalin Lepadatu
Keyword(s):  
Time Series ◽  
Time Series Analysis ◽  
Capacity Planning ◽  
Air Traffic ◽  
Parameter Estimates ◽  
Peak Period ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Series Analysis ◽  
Centre Region

Air traffic in Europe is increasing at a rapid rate and traffic patterns no longer display pronounced daily peaks but instead exhibit peak spreading. Airspace capacity planning can no longer be for the peak period but must consider the whole day. En route airspace capacity in the high density European air traffic network is determined by controller workload. Controller workload is primarily affected by the features of the air traffic and ATC sector. This paper considers the air traffic and ATC sector factors that affect controller workload throughout the whole day. A simulation study using the widely used Reorganized ATC Mathematical Simulator (RAMS) model of air traffic controller workload is conducted for the Central European Air Traffic Services (CEATS) Upper Area Control Centre region of Europe. A cross-sectional time series analysis of the simulation output is conducted with corrections for temporal autocorrelation in the data. The results indicate that a subset of traffic and sector variables and their parameter estimates can be used to predict controller workload in any sector of the CEATS region in any given hour.

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