scholarly journals TRPA1 tunes mosquito thermotaxis to host temperatures

2015 ◽  
Author(s):  
Roman A Corfas ◽  
Leslie B Vosshall
Keyword(s):  
High Temperature ◽  
Body Temperature ◽  
Human Body ◽  
Thermal Environment ◽  
Ambient Air ◽  
Body Temperatures ◽  
Host Body ◽  
Host Seeking ◽  
Thermal Stimuli ◽  
Body Heat

While most ectotherms thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cooling and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective thermotaxis in mosquitoes. During host-seeking, AaegTRPA1-/- mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.

scholarly journals The cation channel TRPA1 tunes mosquito thermotaxis to host temperatures

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Román A Corfas ◽  
Leslie B Vosshall
Keyword(s):  
High Temperature ◽  
Body Temperature ◽  
Thermal Environment ◽  
Ambient Air ◽  
Cation Channel ◽  
Body Temperatures ◽  
Host Body ◽  
Host Seeking ◽  
Thermal Stimuli ◽  
Body Heat

While most animals thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cool and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective thermotaxis in mosquitoes. During host-seeking, AaegTRPA1-/- mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.

Rancang Bangun Pengukur Suhu Tubuh Dengan Multi Sensor Untuk Mencegah Penyebaran Covid-19

2021 ◽  
Vol 5 (3) ◽  
pp. 543-549
Author(s):  
Helmy Yudhistira Putra ◽  
Utomo Budiyanto
Keyword(s):  
Body Temperature ◽  
Temperature Measurement ◽  
Temperature Sensor ◽  
The Body ◽  
Body Temperatures ◽  
Heat Measurement ◽  
Turn On ◽  
Measurement Results ◽  
Door Lock ◽  
Body Heat

During the COVID-19 pandemic, the price of preventive equipment such as masks and hand sanitizers has increased significantly. Likewise, thermometers are experiencing an increase and scarcity, this tool is also sought after by many companies for screening employees and guests before entering the building to detect body temperatures that are suspected of being positive for COVID-19. The use of a thermometer operated by humans is very risky because dealing directly with people who could be ODP (People Under Monitoring/Suscpected ) or even positive for COVID-19, therefore we need tools for automatic body temperature screening and do not involve humans for the examination. This research uses the MLX-90614 body temperature sensor equipped with an ultrasonic support sensor to detect movement and measure the distance between the forehead and the temperature sensor so that the body heat measurement works optimally, and a 16x2 LCD to display the temperature measurement results. If the measured body temperature is more than 37.5 ° C degrees Celsius then the buzzer will turn on and the selenoid door lock will not open and will send a notification to the Telegram messaging application. The final result obtained is the formation of a prototype device for measuring body temperature automatically without the need to involve humans in measuring body temperature to control people who want to enter the building so as to reduce the risk of COVID-19 transmission

scholarly journals Thermal biology, activity, and population parameters of Cnemidophorus vacariensis (Squamata, Teiidae), a lizard endemic to southern Brazil

2011 ◽  
Vol 101 (4) ◽  
pp. 283-295 ◽  
Author(s):  
Rodrigo Caruccio ◽  
Renata Cardoso Vieira ◽  
Laura Verrastro ◽  
Denise Mello Machado
Keyword(s):  
Growth Rate ◽  
Population Structure ◽  
Body Temperature ◽  
Thermal Environment ◽  
Seasonal Activity ◽  
Southern Brazil ◽  
Body Temperatures ◽  
Thermal Biology ◽  
Environment Temperature ◽  
Average Body

We investigated the following aspects of the biology of a population of Cnemidophorus vacariensis Feltrim & Lema, 2000 during the four seasons: thermal biology, relationship with the thermal environment, daily and seasonal activity, population structure and growth rate. Cnemidophorus vacariensis is restricted to rocky outcrops of the "campos de cima da serra" grasslands on the Araucaria Plateau, southern Brazil, and is currently listed as regionally and nationally threatened with extinction. Data were collected from October 2004 through September 2007 in the state of Rio Grande do Sul. Sampling was conducted randomly from 08:00 a.m. to 6:00 p.m. The capture-mark-recapture method was employed. The lizards were captured by hand, and their cloacal temperature, sex, snout-ventral length (SVL), mass, and the temperature of their microhabitat (substrate temperature and air temperature) were recorded. Individuals were then marked by toe-clipping and released at the site of capture. Body temperatures were obtained for 175 individuals, activity data for 96 individuals, and data on population structure and growth for 59 individuals. All data were obtained monthly, at different times of the day. Cnemidophorus vacariensis average body temperature was 23.84ºC, ranging between 9.6 and 38.2ºC. Temperatures ranged between 21 and 29ºC. The correlation between external heat sources, substrate and air were positive and significant and there was a greater correlation between lizard's temperature and the temperature of the substrate (tigmothermic species). The relatively low body temperatures of individuals are associated with the climate of their environment (altitude up to 1,400 m), with large variations in temperature throughout the day and the year, and low temperatures in winter. The average body temperature observed for C. vacariensis was low when compared with that of phylogenetically related species, suggesting that the thermal biology of this species reflects adaptations to the temperate region where it lives. The monthly rates of activity of lizards were related to monthly variations in the ambient temperatures. Our data suggest that the daily and seasonal activity of C. vacariensis result from the interaction between two factors: changes in the environment temperature and the relationship between individuals and their thermal environment. The population structure of C. vacariensis varied throughout the study period, with maximum biomass in January and maximum density in February (recruitment period). The sex ratio diverged from the expected 1:1. The growth analysis showed a negative relationship between the growth rate of individuals and the SVL, revealing that young individuals grow faster than adults, a typical pattern for short-lived species. The population studied showed a seasonal and cyclical variation associated with the reproductive cycle. The life strategy of C. vacariensis seems to include adaptations to the seasonal variations in temperature, typical of its environment.

scholarly journals Effect of exercise and humid heat upon pulse rate, blood pressure, body temperature, and blood concentration

1920 ◽  
Vol 91 (636) ◽  
pp. 111-126 ◽  
Keyword(s):  
Blood Pressure ◽  
High Temperature ◽  
Body Temperature ◽  
Human Body ◽  
Temperate Climate ◽  
Human Organism ◽  
Atmospheric Conditions ◽  
Hot Climate ◽  
The Tropics ◽  
Short Time

The effect of exercise on the human body has been made the subject of much study at different times. Researches have been carried out under atmospheric conditions such as prevail in different parts of Northern Europe, and they have been extended in a few instances to the effects of high temperature and humidity upon the human body. In the latter observations the conditions such as high temperature and varying humidity were produced by artificial means only, and general deductions as to the influence of an actual tropical climate upon the human organism cannot be safely drawn from them. In these experiments the subjects were living in a temperate climate, were exposed to heat and humidity for a short time only, and left the hot chamber at the end of the experiment for an atmosphere of coolness and comfort; in the tropics, on the other hand, the inhabitants are continuously exposed to heat and humidity without respite. Conclusions of real value can thus be drawn only from observations actually carried out in a hot climate, and systematic work in this direction is still lacking. Although observations have been made in the tropics on body temperature, blood pressure, pulse and respiration rate, and metabolism, yet their object has only been to obtain normal standards for the tropics for comparison with those of Europe.

scholarly journals Thermal biology of Amphisbaena munoai (Squamata: Amphisbaenidae)

2018 ◽  
Vol 35 ◽  
pp. 1-9 ◽  
Author(s):  
Nathalia Rocha Matias ◽  
Laura Verrastro
Keyword(s):  
Body Temperature ◽  
Ambient Temperature ◽  
Thermal Environment ◽  
Rio Grande ◽  
The Body ◽  
Rio Grande Do Sul ◽  
Body Temperatures ◽  
Physiological Mechanisms ◽  
Thermal Biology ◽  
The Relationship

Studies on the thermal biology of fossorial reptiles that examine the relationship between the body temperature and thermal environment are needed to determine the extent of their thermoregulation abilities. This study assessed the thermal biology of Amphisbaena munoai Klappenbach, 1969 in the rocky fields of the Rio Grande do Sul and in the laboratory. The body temperature of most individuals was between 24 and 30 °C, both in the field (n = 81) and laboratory (n = 19). More individuals were caught in winter (n = 55) and spring (n = 60) than in summer (n = 25) and fall (n = 45), and in spring, individuals showed similar nocturnal and diurnal activities. In the laboratory, we found individuals with body temperatures up to 5 °C higher than the ambient temperature (n = 4), suggesting that some physiological mechanisms participate in the thermoregulation of these animals. Amphisbaena munoai is a thigmothermic species that is capable of actively regulating its temperature by selecting microhabitats such that its various activities occur within an ideal temperature range. This study is the first to evaluate the effect of seasonality and diurnal and nocturnal variations on the thermoregulation of an amphisbaenid.

scholarly journals Hypothetical model of COVID-19: origin,spread,binding,infection,treatment and prevention(Version10）

2020 ◽  
Author(s):  
Alex Lee
Keyword(s):  
High Temperature ◽  
Body Temperature ◽  
Human Body ◽  
Human Infection ◽  
The Body ◽  
Human Immune System ◽  
Treatment And Prevention ◽  
Hypothesis Model ◽  
The World ◽  
Prevention Method

2019 Coronavirus Hypothesis Model, preliminary hypothesis model, no experiments have been conducted yet. For laboratory reference only, please do not apply this theory before experimental verification. This article discusses the origin of the 2019 Coronavirus, the principles of human infection, the principles of transmission, high binding, changes in human temperature, prevention and treatmen.2019 Coronavirus originates from bats or other animals. In bats, this virus is a cooling factor. Due to the high temperature of bats, this cooling factor lowers the temperature of bats and belongs to normal life activity, it will not produce immune activation, and thus will not produce infections and diseases in the bat body. When this cooling factor enters the human body, especially when the temperature is low, the virus starts the function of the cooling factor in the human body, that is, to lower the human body temperature, the chill happens. The human immune system starts the immune function and gives a fever to fight the cooling. The replication and binding of the 2019 Coronavirus depends on the temperature of the surrounding cells. The higher the temperature, the more replicated and the stronger the binding. Therefore, the fever of the human body promotes the aggravation of the disease. addition to those suspected of having a fever, people whose body temperature is lower than normal may also be infected with 2019 Coronavirus. The way for bats to inhibit the replication of 2019 Coronavirus is high temperature, to avoid body temperature too low. It can be experimented to put the human body in a higher temperature environment, the heat is transmitted to the body, and the low temperature factor of the 2019 Coronavirus can be overcome. The hypothetical prevention method is: everyone in the world isolates for a certain period of time, and raises the temperature around the human body, so that everyone in the world has no 2019 Coronavirus.

scholarly journals Field body temperature and thermal preference of the big-headed turtle Platysternon megacephalum

2013 ◽  
Vol 59 (5) ◽  
pp. 626-632 ◽  
Author(s):  
Jianwei Shen ◽  
Fanwei Meng ◽  
Yongpu Zhang ◽  
Weiguo Du
Keyword(s):  
Food Intake ◽  
Body Temperature ◽  
Thermal Environment ◽  
The Body ◽  
Freshwater Turtle ◽  
Diel Variation ◽  
Thermal Preference ◽  
Body Temperatures ◽  
Low Field ◽  
Preferred Body Temperature

Abstract The big-headed turtle Platysternon megacephalum is a stream-dwelling species whose ecology is poorly known. We carried out field and laboratory investigations to determine field body temperatures and thermal preference of this species. In the field, the body temperatures of the turtles conformed to the water temperature, with little diel variation in either summer or autumn. Over the diel cycle, the mean body temperatures ranged from 20.8°C to 22.2°C in summer and from 19.3°C to 21.2°C in autumn; the highest body temperatures ranged from 22.1°C to 25.0°C in summer and from 20.6°C to 23.8°C in autumn. In the laboratory, the preferred body temperature (Tp) was 25.3°C. Food intake was maximized at 24.0°C, whereas locomotor performance peaked at 30.0°C. Consequently, Tp was closer to the thermal optimum for food intake than for locomotion. Therefore, this freshwater turtle has relative low field body temperatures corresponding to its thermal environment. In addition, the turtle prefers low temperatures and has a low optimal temperature for food intake.

Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude I. The annual fluctuation in body temperature and body temperature increase between 6.30 a.m. and 12.30 p.m.

1960 ◽  
Vol 55 (3) ◽  
pp. 287-294 ◽  
Author(s):  
R. B. Symington
Keyword(s):  
Body Temperature ◽  
Temperature Increase ◽  
Skin Pigmentation ◽  
Ambient Air ◽  
Early Morning ◽  
Coat Colour ◽  
Body Temperatures ◽  
Annual Fluctuation ◽  
Southern Rhodesia ◽  
Body Temperature Increase

Early morning and midday body temperatures of rams and ewes of three breeds of sheep were measured once weekly for a period of 10 months in Northern Rhodesia and 12 months in Southern Rhodesia.1. In all breeds seasonal fluctuations in body temperature were due to concurrent fluctuations in ambient air temperature.2. Mean annual body temperatures were: Merino 102·2° F.; Persian 101·7° F. and Native 101·7° F. Wool and hair breeds differed considerably in their early morning temperatures and in their body temperature increases from 6.30 a.m. to 12.30 p.m. Mean annual values for these measurements were Merino 101·73 and 1·92° F.; Persian 100·81 and 1·83° F.; Native 100·73 and 1–92° F. At all times Merinos showed markedly greater uniformity of body temperature than either hair breed. There was no evidence to show that the thermoregulatory mechanisms of these animals had been stressed unduly.3. Sex had no consistent effect on body temperature or on rise in body temperature.In general, lactating ewes showed a significantly higher initial body temperature than either empty or pregnant ewes, but the respective heat tolerances as measured by body temperature increase did not differ appreciably. Body temperature differed little in empty and pregnant ewes.4. Although the youngest group of ewes in each breed showed the highest early morning temperature, there was no evidence that heat tolerance was less in young than in old animals.5. Black-coated Native ewes had higher initial body temperatures and a smaller body temperature increase during the summer months in Southern Rhodesia than brown or broken-coloured Native ewes. These effects were due to differences in coat density rather than to differences in coat colour or skin pigmentation.6. In all breeds the magnitude of the diurnal and annual variation in body temperature was different in Northern and Southern Rhodesia. Differences were largely of climatic origin but low plane of nutrition in Southern Rhodesia possibly reduced critical body temperature and impaired thermoregulatory ability.

scholarly journals Effects on fetal and maternal body temperatures of exposure of pregnant ewes to heat, cold, and exercise

2002 ◽  
Vol 92 (2) ◽  
pp. 802-808 ◽  
Author(s):  
Helen P. Laburn ◽  
Alida Faurie ◽  
Kathleen Goelst ◽  
Duncan Mitchell
Keyword(s):  
Body Temperature ◽  
Relative Humidity ◽  
Treadmill Exercise ◽  
Thermal Environment ◽  
Heat Exposure ◽  
Body Temperatures ◽  
Maternal Body ◽  
Fetal Lamb ◽  
The Difference ◽  
Pregnant Ewe

We exposed Dorper-cross ewes at ∼120–135 days of gestation to a hot (40°C, 60% relative humidity) and a cold (4°C, 90% relative humidity) environment and to treadmill exercise (2.1 km/h, 5° gradient) and measured fetal lamb and ewe body temperatures using previously implanted abdominal radiotelemeters. When ewes were exposed to 2 h of heat or 30 min of exercise, body temperature rose less in the fetus than in the mother, such that the difference between fetal and maternal body temperature, on average 0.6°C before the thermal stress, fell significantly by 0.54 ± 0.06°C (SE, n = 8) during heat exposure and by 0.21 ± 0.08°C ( n = 7) during exercise. During 6 h of maternal exposure to cold, temperature fell significantly less in the fetus than in the ewe, and the difference between fetal and maternal body temperature rose to 1.16 ± 0.26°C ( n = 9). Thermoregulatory strategies used by the pregnant ewe for thermoregulation during heat or cold exposure appear to protect the fetus from changes in its thermal environment.

scholarly journals The neural basis of temperature-driven host seeking in the human threadworm Strongyloides stercoralis

2021 ◽  
Author(s):  
Astra S Bryant ◽  
Felicitas Ruiz ◽  
Joon Ha Lee ◽  
Elissa A Hallem
Keyword(s):  
Human Body ◽  
Direct Evidence ◽  
Strongyloides Stercoralis ◽  
Parasitic Nematodes ◽  
Body Temperatures ◽  
Neural Basis ◽  
Free Living ◽  
Host Seeking ◽  
Coding Strategies ◽  
Human Body Temperature

Soil-transmitted parasitic nematodes infect approximately one billion people and are a major cause of morbidity worldwide. The infective larvae (iL3s) of these parasites actively search for hosts in a poorly understood, sensory-driven process that requires thermal cues. Here, we describe the neural basis of temperature-driven host seeking in parasitic nematodes using the human threadworm Strongyloides stercoralis. We show that S. stercoralis thermosensation is mediated by the AFD neurons, a thermosensory neuron class that is conserved between parasitic and free-living nematodes. We demonstrate that S. stercoralis AFD displays parasite-specific adaptations that enable both nonlinear and linear encoding of temperatures up to human body temperature. Furthermore, we describe a novel thermosensory behavior in which S. stercoralis iL3s generate spontaneous reversals of temperature preference at below-body temperatures. Finally, we identify three thermoreceptors selectively expressed in S. stercoralis AFD that display parasite-specific sensitivities to human body temperatures and likely enable temperature-driven host seeking by iL3s. Our results are the first direct evidence that the sensory neurons of soil-transmitted parasitic nematodes exhibit parasite-specific neural adaptations and sensory coding strategies that allow them to target human hosts, a finding with important implications for efforts to develop new therapeutic strategies for nematode control.

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