Effect of a Filter Cover on Temperature and Humidity in a Mouse Cage

1968 ◽  
Vol 2 (2) ◽  
pp. 113-120 ◽  
Author(s):  
M. L. Simmons ◽  
D. M. Robie ◽  
J. B. Jones ◽  
L. J. Serrano
Keyword(s):  
Relative Humidity ◽  
Measured Temperature ◽  
Ambient Conditions ◽  
Fibrous Filter ◽  
Water Filter ◽  
Average Temperature ◽  
Temperature And Humidity ◽  
Cent Relative Humidity ◽  
The Mean ◽  
Heat And Moisture

To determine how a filter cap affects the heat and moisture build-up in a mouse cage, and how that build-up is affected by ambient conditions of temperature and relative humidity, 50 adult female mice were housed 10 per cage in polycarbonate cages, which were covered with a fibrous filter and sealed with a neoprene gasket and hold-down rod. The cages were placed in a chamber which controlled ambient temperature and humidity. Observations were made at 1°F intervals of temperature (68–74°F, 19.9–23.3°C) and at three different relative humidities (40, 55, and 70 per cent). Every 24 hours the chamber conditions were changed, and cages, bedding, water, filter caps, and food were replaced. Three sensors suspended just under the filter cover measured temperature and humidity and transmitted the data to a recorder. The first reading was taken after a 3-hour equilibraiion period, then every 3 hours until the next day's change. By measuring the average temperature and humidity, it was possible to study the differences between cage and ambient conditions. At 68°F (19.9°C) and 40 per cent relative humidity, the mean conditions in the cages were 72°F (22.2°C) and 50 per cent; at the upper limit of 74°F (23.3 °C) and 70 per cent, the mean cage conditions were 78°F (25.5°C) and 75 per cent.

scholarly journals The Effect of Temperature and Humidity May Reduce the Growth Rate of the Coronavirus Disease 2019 Epidemic

2020 ◽  
Author(s):  
Lei Qin ◽  
Qiang Sun ◽  
Jiani Shao ◽  
Yang Chen ◽  
Xiaomei Zhang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Relative Humidity ◽  
Effect Of Temperature ◽  
Average Temperature ◽  
Temperature And Humidity ◽  
Scatter Plots ◽  
Low Humidity ◽  
Average Relative Humidity ◽  
Effects Of Temperature ◽  
The Relationship

Abstract Background: The effects of temperature and humidity on the epidemic growth of coronavirus disease 2019 (COVID-19)remains unclear.Methods: Daily scatter plots between the epidemic growth rate (GR) and average temperature (AT) or average relative humidity (ARH) were presented with curve fitting through the “loess” method. The heterogeneity across days and provinces were calculated to assess the necessity of using a longitudinal model. Fixed effect models with polynomial terms were developed to quantify the relationship between variations in the GR and AT or ARH.Results: An increased AT dramatically reduced the GR when the AT was lower than −5°C, the GR was moderately reduced when the AT ranged from −5°C to 15°C, and the GR increased when the AT exceeded 15°C. An increasedARH increased theGR when the ARH was lower than 72% and reduced theGR when the ARH exceeded 72%.Conclusions: High temperatures and low humidity may reduce the GR of the COVID-19 epidemic. The temperature and humidity curves were not linearly associated with the COVID-19 GR.

Memoirs: The Early Embryonic Development of Rhodnius Prolixus (Hemiptera, Heteroptera)

1935 ◽  
Vol s2-78 (309) ◽  
pp. 71-90
Author(s):  
HELEN MELLANBY
Keyword(s):  
Relative Humidity ◽  
Embryonic Development ◽  
Early Development ◽  
Constant Temperature ◽  
Germ Cells ◽  
Rhodnius Prolixus ◽  
Posterior Pole ◽  
Early Embryonic Development ◽  
Temperature And Humidity ◽  
Cent Relative Humidity

1. Eggs of Rhodnius prolixus were incubated at constant temperature and humidity (21° C. and 90 per cent, relative humidity). Eighty-five per cent, was the lowest record of the controls hatched successfully under these conditions. 2. The processes of maturation and fertilization were not studied. 3. Cleavage begins 12-13 hours after incubation. At 25 hours there are 32 nuclei. Yolk-cells are derived from cleavage nuclei, and they multiply by mitosis up to 50 hours. Blastoderm formation is complete after 55-60 hours of incubation. 4. The ventral embryonic rudiment is similar to that of many other insects. As soon as it is formed, germ-cells are budded off at the posterior pole of the egg. 5. The first stage in blastokinesis is fully described. 6. The formation of the mesoderm is by invagination and overgrowth. 7. The endoderm arises from two proliferating areas situated anteriorly and posteriorly. 8. Numerous cells are given off into the yolk during the early development of the embryo. There they disintegrate.

scholarly journals The impact of climate change on the resin productivity of dammar tree (Agathis alba) in Inamosol subdistrict, West Seram district, Maluku-Indonesia

2021 ◽  
Vol 883 (1) ◽  
pp. 012079
Author(s):  
J M Matinahoru
Keyword(s):  
Climate Change ◽  
Relative Humidity ◽  
Sampling Technique ◽  
Climate Data ◽  
Purposive Sampling ◽  
Impact Of Climate Change ◽  
Average Temperature ◽  
Change Factors ◽  
Temperature And Humidity ◽  
The Impact

Abstract This research was aimed to determine the impact of climate change on the resin productivity of dammar tree. This research will be useful as data and information for farmers and government to maintain the resin of dammar tree to be optimal and sustainable in production. This research was conducted in Inamosol Sub-district, West Seram District, Maluku Indonesia, during September-October 2020. Village and farmer samples were determined by purposive sampling technique. The selected villages were Honitetu, Hukuanakota and Rambatu. Furthermore, from each village, It was ten farmers to select for interviews and filling the questionnaire. The results showed that the average resin production of farmers in 2019 was 904.2 kg/farmer, while in 2020 was 523.7 kg/farmer. This means that it occurred a decline in resin production in 2020 about 42.08 % for each farmer—the leading cause of the decreased production as climate change factors, namely rainfall, temperature and humidity. Based on climate data of West Seram District in 2019 indicated that rainfall has occurred during six months with an average temperature of 27 °C and relative humidity of 82 %. Meanwhile, in 2020 the rainfall occurs for nine months with an average temperature of 26.5 °C, and relative humidity of 85 %.

Importance of Temperature and Humidity Control in Rubber Testing. II—Resistance to Abrasion

1929 ◽  
Vol 2 (4) ◽  
pp. 680-697
Author(s):  
W. A. Gibbons ◽  
J. M. Bierer ◽  
E. R. Bridgewater ◽  
D. F. Cranor ◽  
C. R. Park ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Experimental Error ◽  
Negligible Effect ◽  
Stress Strain ◽  
Humidity Control ◽  
Temperature Changes ◽  
Constant Relative Humidity ◽  
Temperature And Humidity ◽  
Cent Relative Humidity ◽  
Great Error

Abstract This study shows that in determining resistance to abrasion the temperature of the room or cabinet should be controlled within ± 1 ° C. in order to avoid significant errors in the results from this source. Below are shown the percentage differences per degree Centigrade obtained with each of the stocks. It must be remembered that this probably holds only over the range of temperatures studied and might change rapidly outside of this range. As the temperature changes from 15 ° C. to 35 ° C., the resistance to abrasion changes per degree Centigrade in the following manner: In the light of the present investigation there will be no great error in results caused by differences in relative humidity either with the raw or vulcanized stock. Where laboratories are equipped to condition raw and vulcanized stock for stress-strain tests, it appears that it would be advisable also to condition samples for determining resistance to abrasion. It would at least tend to produce more nearly uniform results by eliminating possible sources of small errors. As the relative humidity during exposure of raw stock increases from 10 per cent to 100 per cent, the resistance to abrasion per 1 per cent relative humidity changes roughly in the following manner: As these variations are small compared with the experimental error, it is evident that if the relative humidity does not vary over too wide a range its effect may be neglected. The temperature of storing the cured samples while maintaining a constant relative humidity has a negligible effect as in the case of relative humidity. As the temperature increases the resistance to abrasion per degree changes in the following manner:

DIAGNÓSTICO BIOCLIMÁTICO PARA A PRODUÇÃO DE AVES DE CORTE EM DIFERENTES MUNICÍPIOS DO RS

2017 ◽  
Vol 32 (4) ◽  
pp. 372
Author(s):  
Zanandra Boff Oliveira ◽  
Alberto Eduardo Knies
Keyword(s):  
Relative Humidity ◽  
Rio Grande ◽  
Poultry Production ◽  
Rio Grande Do Sul ◽  
Average Temperature ◽  
The Third ◽  
Temperature And Humidity ◽  
Humidity Index ◽  
Poultry Farming

O presente trabalho teve como objetivo realizar o diagnóstico bioclimático para a produção de aves de corte em diferentes municípios do Rio Grande do Sul. Para isso, foram utilizados os dados de temperatura média compensada (TMC) e umidade relativa compensada (URC), referentes ao período compreendido entre 1961 e 1990, disponíveis no site do INMET, para os municípios de: Cachoeira do Sul, Caxias do Sul, Guaporé, Lagoa Vermelha, Passo Fundo, Santana do Livramento, São Gabriel e Uruguaiana. Os valores do Índice de Umidade e Temperatura (ITU) para avicultura de corte foram calculados através da equação proposta por Bunffington et al. (1982). Os resultados demonstram que nas três primeiras semanas de vida dos animais, prevalece o ITU inferior ao de conforto, já a partir da terceira semana, prevalece o ITU superior ao de conforto. Na média dos municípios, o ITU fica na faixa de conforto durante quatro meses do ano para a criação de aves com uma, duas, três e seis semanas de vida e, cinco meses do ano para a criação de aves com quatro e cinco semanas de vida. Assim, o presente diagnóstico indica, para o RS, a necessidade de modificações no ambiente de criação, tanto de aquecimento quanto de resfriamento, para atender as das aves de corte em diferentes idades.PALAVRAS-CHAVE: Índice de Temperatura e Umidade; Avicultura; Ambiência. BIOCLIMATIC DIAGNOSIS FOR BROILERS PRODUCTION IN DIFFERENT RIO GRANDE DO SUL MUNICIPALITIESABSTRACT: This study aimed the bioclimatic diagnosis of broilers  production in different municipalities of Rio Grande do Sul. For this  average temperature compensated  (TMC) and offset relative humidity (URC) INMET data  from 1961 to 1990 were used. from the following municipalities: Cachoeira do Sul, Caxias do Sul, Guapore, Lagoa Vermelha, Passo Fundo, Santana do Livramento, Sao Gabriel, and Uruguaiana. The values of Temperature and Humidity Index (ITU) for poultry production were calculated using the equation proposed by Bunffington (1977). The results demonstrate that in the first three weeks of life of the animals, the prevailing ITU lower than comfort, as from the third week, reigns ITU higher than comfort. The average of the municipalities, the ITU is the comfort range for four months of the year for rearing birds with one, two, three and six weeks of life, and five months for poultry with four and five weeks life. Thus, the present diagnostic indicates to the RS, the need for changes in the environment, either as heating cooling, to meet as the broilers of cut at different ages.KEYWORDS: Temperature and Humidity Index; Poultry farming; Ambience.

scholarly journals The Conditions of Temperature and Humidity of the Air between the Skin and Shirt of Man

1932 ◽  
Vol 32 (2) ◽  
pp. 268-274 ◽  
Author(s):  
Kenneth Mellanby
Keyword(s):  
Relative Humidity ◽  
Temperature And Humidity ◽  
Cent Relative Humidity

Methods for measuring the temperature and humidity of the air beneath the shirt are described.Conditions of temperature and humidity under the shirt are described, for a resting person, with external temperatures varying between 0° C. and 41° C., under different atmospheric humidities. The air beneath the shirt varied between 23° C. and 37° C., and 23 and 70 per cent. relative humidity. The saturation deficiency of the air beneath the shirt varied very little—only between 13 and 18 mm.—in all the observations taken.I am indebted to Dr P. A. Buxton for many helpful suggestions and for reading the manuscript. Also to Prof. G. H. F. Nuttall, F.R.S., for drawing my attention to literature on the earlier work.

Importance of Temperature and Humidity Control in Rubber Testing. Progress Report of the Physical Testing Commitee, Rubber Division, A.C.S. (Dated Dec. 8, 1927)

1928 ◽  
Vol 1 (1) ◽  
pp. 182-191
Author(s):  
J. E. Partenheimer ◽  
E. R. Bridgwater ◽  
D. F. Cranor ◽  
E. B. Curtis ◽  
J. W. Schade ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Absolute Humidity ◽  
Rubber Compounds ◽  
Physical Testing ◽  
Temperature And Humidity ◽  
Cent Relative Humidity ◽  
Physical Tests ◽  
A Minor ◽  
Mixed Stock ◽  
Testing Room

Abstract The purpose of the work which this committee has undertaken is to determine the effect of the variables which influence the results of physical tests on rubber. The investigation has proven that variations in temperature which may occur from day to day in an uncontrolled testing room may affect the physical tests to as great a degree as a 25 to 40 per cent change in the time of cure, while relative humidity affects the results to only a minor degree. Furthermore, variations in the absolute humidity of the room in which the unvulcanized rubber is stored between the time of mixing and the time of curing may affect the tensile strength and modulus of rubber compounds to as great a degree as does the temperature after curing. It is, therefore, apparent that laboratory tests which are conducted under uncontrolled conditions of temperature and humidity may give highly erroneous results and may even give misinformation which is worse than no information at all. The committee, therefore, recommends that mixed stock prior to curing and cured stock prior to testing be conditioned for not less than twenty-four nor more than twenty-eight hours at 82 deg. F. ± 2 deg. and 45 per cent relative humidity ± 3 per cent and that the testing room be maintained at 82 deg. F. ± 2 deg. If a temperature of 82 deg. F. cannot be maintained for conditioning the mixed stock prior to curing, the committee recommends a relative humidity corresponding to the temperature used which gives an absolute humidity equal to that obtained under the former conditions. The temperature of the testing room should be controlled within the above stated limits, but it is not necessary to control the humidity of the entire room. A small conditioning cabinet in which the standard humidity is maintained has been found to be sufficient.

The effects of rearing conditions on the immature stages and adults ofSpodoptera littoralis(Boisd.)

1966 ◽  
Vol 56 (4) ◽  
pp. 623-634 ◽  
Author(s):  
E. Rivnay ◽  
J. Meisner
Keyword(s):  
Relative Humidity ◽  
Life Span ◽  
Spodoptera Littoralis ◽  
Pupal Stage ◽  
Sugar Solution ◽  
Larval Life ◽  
Rearing Conditions ◽  
Cent Relative Humidity ◽  
The Mean ◽  
Pupal Mortality

Some effects on the adult of environmental conditions during the larval and pupal stages ofSpodoptera littoralis(Boisd.) were investigated in the laboratory in Israel. The conditions studied were temperature during larval life, temperature and humidity during pupal life and the density at which larvae were kept, and their effects were found by varying one of them at a time. Except for such variations, larvae were reared in batches of 30–50 at 22–24°C. and 60–70 per cent, relative humidity, pupae were kept at 23–24°C. and 70–80 per cent, relative humidity, and adults were kept in pairs at 20–21 °C. and 75–85 per cent, relative humidity. Larvae were fed on clover leaves and adults on sugar solution.High temperature during the larval stage reduced fecundity; whereas at 22°C. the resultant females laid about 1,200 eggs each and 12·5 per cent, produced non-viable ones only, at 30°C. they averaged about 700 eggs each and 50 per cent, produced non-viable ones only. Temperature during the pupal stage affected fecundity similarly and life-span to a lesser extent; at 20 and 34°C., 40 and 5 per cent, of the resultant adults lived 15 days or more, the percentages of females laying only non-viable eggs were nil and 70 and the mean numbers of eggs laid were about 1650 and 700, of which about 60 and 2 per cent, were viable, respectively. High temperatures were directly inimical to pupae, less than half of which survived at 26°C. or over.The effects of humidity during the pupal stage were in general less than those of temperature. The mean life-span was longest in adults from pupae kept at an intermediate humidity of 76 per cent., as also were the proportion of barren females and the mean number of eggs laid; the percentage of viable eggs was reduced only amongst those from females kept as pupae at over 95 per cent, relative humidity. Pupal mortality was affected only by low relative humidities, which raised it.Larvae reared singly tended to be brighter in colour than those reared in batches of 30–50; fewer died and the subsequent pupae were heavier and longer. The mean life-span of the resultant adults was longer, and they laid more eggs.The results are compared with those of other workers onS. littoralisand other insects.

scholarly journals Influence of Temperature and Humidity on Survival of Penicillium digitatum and Geotrichum citri-aurantii

Plant Disease ◽  
2007 ◽  
Vol 91 (8) ◽  
pp. 990-996 ◽  
Author(s):  
J. L. Smilanick ◽  
M. F. Mansour
Keyword(s):  
Relative Humidity ◽  
Potato Dextrose Agar ◽  
Penicillium Digitatum ◽  
Ambient Conditions ◽  
Central California ◽  
Influence Of Temperature ◽  
Sour Rot ◽  
Green Mold ◽  
Temperature And Humidity

Longevity of conidia of Penicillium digitatum (cause of citrus green mold) and arthroconidia of Geotrichum citri-aurantii (cause of sour rot of citrus) was determined under controlled temperature and relative humidity (RH) or ambient summer conditions in central California. Longevity at low RH was longer than at high RH. Hours to kill 99% of the conidia (LT99) of nine P. digitatum isolates were determined at 50°C and 75 or 95% RH. At 75 and 95% RH, the LT99 was 24.9 and 4.9 h, respectively. The LT99 was 30 and 42 days, respectively, for conidia of P. digitatum under ambient conditions at two outdoor locations. The LT99 of arthroconidia of G. citriaurantii from colonies cultured on potato dextrose agar was briefer than that of conidia of P. digitatum. At 45°C and 75 or 95% RH, the LT99 was about 4 and 2 h, respectively, whereas at 50°C, none was viable after 1 h at either humidity. Sanitation is an important practice for managing these diseases. Since there was little or no survival of either fungus after 1 day at 50°C and 75% RH or higher, we conclude that commercial sanitation could employ a similar regime.

scholarly journals Epidemiological Studies of Brown Rot in Spanish Cherry Orchards in the Jerte Valley

2021 ◽  
Vol 7 (3) ◽  
pp. 203
Author(s):  
Inmaculada Larena ◽  
Maria Villarino ◽  
Paloma Melgarejo ◽  
Antonieta De Cal
Keyword(s):  
Relative Humidity ◽  
Critical Period ◽  
Fruit Set ◽  
Brown Rot ◽  
Epidemiological Studies ◽  
Forecasting Model ◽  
Average Temperature ◽  
Percent Relative Humidity ◽  
Cherry Orchard ◽  
The Mean

Cherry brown rot caused by Monilinialaxa was observed and estimated in organic cherry orchard located in the Jerte Valley between 2013 and 2018 (Cáceres, Spain). Climatic variables were collected from this orchard and also from a nearby weather station. The primary inoculum of the pathogen recorded in March was detected in overwintered mummified fruits, ground mummies, and necrotic twigs and was a function of the average temperature of the previous three months (December, January, and February). The first symptoms of brown rot could be observed on flowers until fruit set in April. The months of March and April were identified as the critical period for cherry brown-rot development. A significant positive correlation was identified between brown rot observed at harvest and the mean number of consecutive days in each fortnight of March and April when the percent relative humidity was above 80%. Brown-rot incidence observed over the 6 years ranged from 0 to 38%. More than 11 days with relative humidity >80% in each fortnight of critical period would mean 100% of cherry brown rot at harvest. A forecasting model could be used to predict brown rot infection in Jerte Valley cherries.

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