Partitional Heat Losses of Newborn Pigs as Affected by Air Temperature, Absolute Humidity, Age and Body Weight

1964 ◽  
Vol 7 (4) ◽  
pp. 0380-0383 ◽  
Author(s):  
A. F. Butchbaker and Milton D. Shanklin
Keyword(s):  
Body Weight ◽  
Air Temperature ◽  
Absolute Humidity ◽  
Heat Losses ◽  
Newborn Pigs

Wildfire and Postfire Restoration Action Effects on Microclimate and Seedling Pine Tree Survivorship

2014 ◽  
Vol 5 (1) ◽  
pp. 174-182 ◽  
Author(s):  
Donald J. Brown ◽  
Ivana Mali ◽  
Michael R.J. Forstner
Keyword(s):  
Soil Moisture ◽  
Wind Speed ◽  
Soil Temperature ◽  
Air Temperature ◽  
Loblolly Pine ◽  
Absolute Humidity ◽  
Short Term ◽  
Burned Areas ◽  
High Severity ◽  
Postfire Management

Abstract Through modification of structural characteristics, ecological processes such as fire can affect microhabitat parameters, which in turn can influence community composition dynamics. The prevalence of high-severity forest fires is increasing in the southern and western United States, creating the necessity to better understand effects of high-severity fire, and subsequent postfire management actions, on forest ecosystems. In this study we used a recent high-severity wildfire in the Lost Pines ecoregion of Texas to assess effects of the wildfire and postfire clearcutting on six microclimate parameters: air temperature, absolute humidity, mean wind speed, maximum wind speed, soil temperature, and soil moisture. We also assessed differences between burned areas and burned and subsequently clearcut areas for short-term survivorship of loblolly pine Pinus taeda seedling trees. We found that during the summer months approximately 2 y after the wildfire, mean and maximum wind speed differed between unburned and burned areas, as well as burned and burned and subsequently clearcut areas. Our results indicated air temperature, absolute humidity, soil temperature, and soil moisture did not differ between unburned and burned areas, or burned and burned and subsequently clearcut areas, during the study period. We found that short-term survivorship of loblolly pine seedling trees was influenced primarily by soil type, but was also lower in clearcut habitat compared with habitat containing dead standing trees. Ultimately, however, the outcome of the reforestation initiative will likely depend primarily on whether or not the trees can survive drought conditions in the future, and this study indicates there is flexibility in postfire management options prior to reseeding. Further, concerns about negative wildfire effects on microclimate parameters important to the endangered Houston toad Bufo (Anaxyrus) houstonensis were not supported in this study.

Differential induction of peroxisomal β-oxidation enzymes by clofibric acid and aspirin in piglet tissues

2001 ◽  
Vol 281 (5) ◽  
pp. R1553-R1561 ◽  
Author(s):  
Xing Xian Yu ◽  
Jack Odle ◽  
James K. Drackley
Keyword(s):  
Body Weight ◽  
Liver Weight ◽  
Fatty Acyl ◽  
Clofibric Acid ◽  
Heart Weight ◽  
Final Body Weight ◽  
Daily Food ◽  
Newborn Pigs ◽  
Acyl Coa Oxidase ◽  
Total Carnitine

Peroxisomal β-oxidation (POX) of fatty acids is important in lipid catabolism and thermogenesis. To investigate the effects of peroxisome proliferators on peroxisomal and mitochondrial β-oxidation in piglet tissues, newborn pigs (1–2 days old) were allowed ad libitum access to milk replacer supplemented with 0.5% clofibric acid (CA) or 1% aspirin for 14 days. CA increased ratios of liver weight to body weight ( P < 0.07), kidney weight to body weight ( P< 0.05), and heart weight to body weight ( P < 0.001). Aspirin decreased daily food intake and final body weight but increased the ratio of heart weight to body weight ( P < 0.01). In liver, activities of POX, fatty acyl-CoA oxidase (FAO), total carnitine palmitoyltransferase (CPT), and catalase were 2.7-, 2.2-, 1.5-fold, and 33% greater, respectively, for pigs given CA than for control pigs. In heart, these variables were 2.2-, 4.1-, 1.9-, and 1.8-fold greater, respectively, for pigs given CA than for control pigs. CA did not change these variables in either kidney or muscle, except that CPT activity was increased ∼110% ( P < 0.01) in kidney. Aspirin increased only hepatic FAO and CPT activities. Northern blot analysis revealed that CA increased the abundance of catalase mRNA in heart by ∼2.2-fold. We conclude that 1) POX and CPT in newborn pigs can be induced by peroxisomal proliferators with tissue specificity and 2) the relatively smaller induction of POX in piglets (compared with that in young or adult rodents) may be related to either age or species differences.

Influence of Environmental-Conditions on Flight Duration of Epiphyas-Postvittana (Walker) (Lepidoptera, Tortricidae)

1992 ◽  
Vol 40 (5) ◽  
pp. 477 ◽  
Author(s):  
W Danthanarayana ◽  
H Gu
Keyword(s):  
Body Weight ◽  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Epiphyas Postvittana ◽  
Atmospheric Humidity ◽  
Flight Duration ◽  
Reduced Body ◽  
Light Brown Apple Moth ◽  
Honey Solution

Flight responses of the light brown apple moth, Epiphyas postvittana (Walker), to changes in air temperature, atmospheric humidity, feeding and mating activities were studied under controlled conditions. Flights occurred within the air temperature range from 10 to 30-degrees-C, with the longest flight duration at 20-degrees-C for both sexes. A change of atmospheric humidity significantly influenced flight duration of females, but not of males, at 20-degrees-C. The longest flight duration of the female moths occurred at a relative humidity of 60%. Provision of honey solution or water improved flight duration of the moths aged three days or older. Mating increased flight duration of females from the age of three days onwards, presumably as a result of reduced body weight associated with oviposition.

scholarly journals The Impact of Infiltration on Heating Systems Dimensioning in Estonian Climate

2020 ◽  
Vol 172 ◽  
pp. 05004
Author(s):  
Raimo Simson ◽  
Taaniel Rebane ◽  
Martin Kiil ◽  
Martin Thalfeldt ◽  
Jarek Kurnitski
Keyword(s):  
Air Temperature ◽  
Indoor Air ◽  
Energy Performance ◽  
Simulation Software ◽  
Heat Losses ◽  
Climatic Data ◽  
Heating Systems ◽  
Air Temperatures ◽  
The Impact ◽  
Calculation Models

In this study we analysed the climatic conditions for infiltration estimation, different calculation methods and infiltration impact on heat load for heating systems dimensioning. To determine the wind conditions at low air temperatures of the coastal- and inland climatic zones in Estonia, 42 years of climatic data for Tallinn and Tartu were investigated. Calculation models with detailed air leakages were constructed of a single and two-storey detached house using dynamic simulation software IDA ICE. Simulations were carried out with the constructed calculation models, simulating various wind and sheltering conditions to determine the heating load of the buildings under measured wind conditions at the design external air temperatures. The simulation results were compared with results calculated with European Standard EN 12831:2017, methodology given in the Estonian regulation for calculating energy performance of buildings and with simulations using the default settings in IDA ICE based on the ASHRAE design day conditions. The percentage of heat losses caused by infiltration was found as 13-16% of all heat losses for the studied buildings. Simulations with historical climate periods showed that even in windy weather conditions the heating system dimensioned by the methods analysed may not be able to provide the required indoor air temperature. Analysis using the coldest and windiest periods showed that when systems are dimensioned by the studied methods, the highest decline in indoor air temperature occurs on the windiest day and not on the coldest day. The impact of high wind speeds and low sheltering conditions resulted up to 50% of all heat losses.

Performance Evaluation of a Smart Mobile Air Temperature and Humidity Sensor for Characterizing Intracity Thermal Environment

2020 ◽  
Vol 37 (10) ◽  
pp. 1891-1905
Author(s):  
Chang Cao ◽  
Yichen Yang ◽  
Yang Lu ◽  
Natalie Schultze ◽  
Pingyue Gu ◽  
...  
Keyword(s):  
Air Temperature ◽  
Humidity Sensor ◽  
Thermal Environment ◽  
Spatial Scales ◽  
Low Cost ◽  
Thermal Conditions ◽  
Absolute Humidity ◽  
Health Concern ◽  
Vegetation Fraction ◽  
Temperature And Humidity

AbstractHeat stress caused by high air temperature and high humidity is a serious health concern for urban residents. Mobile measurement of these two parameters can complement weather station observations because of its ability to capture data at fine spatial scales and in places where people live and work. In this paper, we describe a smart temperature and humidity sensor (Smart-T) for use on bicycles to characterize intracity variations in human thermal conditions. The sensor has several key characteristics of internet of things (IoT) technology, including lightweight, low cost, low power consumption, ability to communicate and geolocate the data (via the cyclist’s smartphone), and the potential to be deployed in large quantities. The sensor has a reproducibility of 0.03°–0.05°C for temperature and of 0.18%–0.33% for relative humidity (one standard deviation of variation among multiple units). The time constant with a complete radiation shelter and moving at a normal cycling speed is 9.7 and 18.5 s for temperature and humidity, respectively, corresponding to a spatial resolution of 40 and 70 m. Measurements were made with the sensor on street transects in Nanjing, China. Results show that increasing vegetation fraction causes reduction in both air temperature and absolute humidity and that increasing impervious surface fraction has the opposite effect.

The metabolic rates of newborn pigs in relation to floor insulation and ambient temperature

1971 ◽  
Vol 13 (2) ◽  
pp. 303-313 ◽  
Author(s):  
D. B. Stephens
Keyword(s):  
Body Weight ◽  
Oxygen Consumption ◽  
Ambient Temperature ◽  
Regression Coefficients ◽  
Metabolic Rates ◽  
Similar Treatment ◽  
Concrete Floor ◽  
Ambient Temperatures ◽  
Newborn Pigs ◽  
Floor Material

SUMMARY1. The metabolic rates of 58 individual piglets kept either on a straw or on a concrete floor at ambient temperatures near to 10°, 20° or 30°C have been measured with ages ranging from newborn to 9 days, and body weight from 1·0 to 3·2 kg. The oxygen consumption was measured on each floor material at the chosen ambient temperature thus allowing paired comparisons for each animal.2. In comparison with the concrete floor, oxygen consumption on straw was reduced by 18% at 10°C, 27% at 20°C and by 12% at 30°C for pigs 2 to 9 days old. The regression coefficients of mean log (oxygen consumption) on log (body weight) were around 0·66 at 10° and 20°C. At 30°C the value was 0·99 ± 0·14. The regression coefficients were not significantly affected by the presence of a straw floor showing that its effect did not vary with body weight. Corresponding values foi piglets below 24 hours of age were 17% at 10°C, 27% at 20°C and 22% at 30°C ambient temperature.3. Moving a piglet on to a straw floor at 10°C had the same thermal effect as raising the ambient temperature to 18°C. Similar treatment at 30°C was equivalent to raising the ambient temperature to 32°C.4. Lowering ambient temperature to increase the temperature gradient between the homeothermic body of the piglet and the environment progressively increased heat loss in all cases. There was a concomitant decrease in the calculated conductance between core and environment which was more pronounced for the piglets lying on the concrete floor.

Transient Response of Heated Air in an Enclosure With Heat Losses

1959 ◽  
Vol 81 (1) ◽  
pp. 19-23 ◽  
Author(s):  
W. A. Wolfe
Keyword(s):  
Differential Equation ◽  
Heat Capacity ◽  
Air Temperature ◽  
Transient Response ◽  
Heat Losses ◽  
Transient Temperature ◽  
Heated Air

The transient temperature of well-stirred air in an enclosure with heat losses is investigated. The introduction of the heat capacity of the air results in nonorthogonal eigenfunctions for the differential equation of conduction. A method of determining the coefficients of the eigenfunctions is developed and the transient-air temperature calculated for several values of the heat capacity of the air.

scholarly journals Some glacio-micrometeorological features on the north side of Mount Qogir (K2), Karakoram mountains

1992 ◽  
Vol 16 ◽  
pp. 67-72 ◽  
Author(s):  
Ding Yongjian
Keyword(s):  
Air Temperature ◽  
Absolute Humidity ◽  
Night Time ◽  
Valley Wind ◽  
Ablation Area ◽  
The North ◽  
Ice Surface ◽  
Diurnal Range ◽  
Dry Valley ◽  
Micrometeorological Conditions

Measurement of wind velocity, wind direction, air temperature, precipitation and humidity were obtained at various altitudes in order to describe micrometeorological conditions on the north slope of Mount Qogir (K2). Meteorological elements were monitored above the moraine surface in the proglacial area and over the ice surface in the ablation area and snow surface in the firn area of K2 glacier. Precipitation increases quickly with altitude from the dry valley to the firn area. Relative humidity also increases with elevation. In the K2 glacier area, the highest absolute humidity occurs over the glacier tongue. The effects of melting and freezing of the surface of the glacier in the ablation area on diurnal and day-to-day changes in air temperature influence air temperature in ablation areas, decreasing diurnal range by comparison with the firn areas. On clear days, a down-valley wind blows from the firn area before sunrise and an up-valley wind after sunrise. On days with precipitation, an up-valley wind predominates in the night-time and a down-valley wind in the day-time.

Consistent large-scale response of hourly extreme precipitation to temperature variability

2021 ◽  
Author(s):  
Haider Ali ◽  
Hayley Fowler ◽  
Geert Lenderink
Keyword(s):  
Air Temperature ◽  
Large Scale ◽  
Surface Air Temperature ◽  
Absolute Humidity ◽  
Tropical Regions ◽  
Local Scaling ◽  
Hourly Precipitation ◽  
Dewpoint Temperature ◽  
Scale Response ◽  
Temperature Scaling

&lt;p&gt;Hourly precipitation extremes can intensify with higher temperatures at higher rates than theoretically expected from thermodynamic increases explained by the Clausius-Clapeyron (CC) relationship (~6.5%/K), but local scaling with surface air temperature is highly variable. Here, we use daily dewpoint temperature, a direct proxy of absolute humidity, as the scaling variable instead of surface air temperature. Using a global dataset of over 7000 hourly precipitation gauges, we estimate the at-gauge local scaling across six macro-regions; this ranges from CC to 2xCC for more than 60% of gauges. We find positive scaling in subtropical and tropical regions in contrast to previous work. Moreover, regional scaling rates show surprisingly universal behaviour at around CC, with higher scaling rates in Europe. Our results show a much greater consistency of scaling across the globe than previous work, usually at or above the CC rate, suggesting the relevance of dewpoint temperature scaling to understand future changes. &amp;#160;&amp;#160;&lt;/p&gt;

Relative control of air temperature and water status on seasonal transpiration of Pinuscontorta

1984 ◽  
Vol 14 (6) ◽  
pp. 833-838 ◽  
Author(s):  
Jeff S. Graham ◽  
Steven W. Running
Keyword(s):  
Water Potential ◽  
Air Temperature ◽  
Water Status ◽  
Environmental Parameters ◽  
Absolute Humidity ◽  
Hydrologic Model ◽  
Leaf Conductance ◽  
Seasonal Temperature ◽  
Regression Equations ◽  
Previous Night

Leaf conductance was measured periodically from early spring until October for three Pinuscontorta Dougl. saplings in Western Montana on a harsh site exhibiting low temperatures, high absolute humidity deficits, and substantial soil moisture depletion. Springtime maximum daily leaf conductance was correlated with previous night minimum air temperature and a seasonal temperature summation (R2 = 0.93). Summer leaf conductance was correlated with predawn leaf water potential and absolute humidity deficit (R2 = 0.87). To assess the significance of these leaf conductance controls to the seasonal water balance of a forest stand on this site, regression equations relating leaf conductance to environmental parameters were incorporated into a stand hydrologic model. Removing spring air temperature controls of leaf conductance was estimated to increase transpiration in May and June by 47%; however, overall seasonal transpiration was increased by only 8%. Summer humidity and predawn water potential controls were found necessary to prevent lethal water stress.

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