Nitrogen and sulfur metabolism and plasma thyroid hormone concentrations in fleeceweight-selected and control Romney sheep at two ambient temperatures

1994 ◽  
Vol 45 (2) ◽  
pp. 339 ◽  
Author(s):  
YX Sun ◽  
J Lee ◽  
PM Harris ◽  
BR Sinclair ◽  
ID Shelton ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Nitrogen Balance ◽  
Whole Blood ◽  
Dry Matter ◽  
Sulfur Metabolism ◽  
Selection Line ◽  
Irreversible Loss ◽  
Ambient Temperatures ◽  
And Control ◽  
Loss Rates

This study was conducted to determine the effect of ambient temperature on nitrogen and sulfur metabolism in 7-month-old rams from the Massey University fleeceweight-selected (FW) and control (C) lines of Romney sheep. Eight rams from each line were exposed to either 6�C or 25�C ambient temperature under a constant photoperiod. Detailed studies of sulfur metabolism were made on four of the rams from each line at each ambient temperature. Intake and faecal output of dry matter and nitrogen were lower at 25�C than at 6�C, but there was no effect of ambient temperature on digestibility of either dry matter or nitrogen. Nitrogen balance was lower at 25�C than at 6�C, but none of the parameters relating to nitrogen balance was influenced by selection line. There were also no effects of ambient temperature or selection line on clearance rates of urea or creatinine. Blood samples were collected from the animals at 2 h intervals over a 24 h period to determine plasma concentrations of urea, creatinine, thyroxine and triiodothyronine. Although the between-line differences in concentrations of these hormones and metabolites varied throughout the 24 h period, and with ambient temperature, there were no consistent interactions between the effects of selection line and ambient temperature. There were no consistent effects of selection line, or interactions of selection line with ambient temperature, on sulfur and sulfate balances, concentrations of leucine, cyst(e)ine and glutathione in whole blood or on irreversible loss rates of leucine and cyst(e)ine. However, when considered across lines and ambient temperatures, both the whole blood concentrations (P < 0.10) and the irreversible loss rates (P < 0.05) of leucine and cyst(e)ine were positively related to midside wool growth. The only significant (P < 0.05) interaction between selection line and ambient temperature was observed in the wool sulfur concentration which was lower in the FW rams than in the C rams at 6�C, but not at 25�C. It is concluded that none of the metabolic measurements made in this study explains previous inconsistencies observed in metabolic differences between sheep from lines divergently selected on the basis of fleeceweight. Wool sulfur content was again shown to be a potentially useful predictor of genetic merit for fleeceweight, but no clear metabolic basis for differences between the lines could be demonstrated even with detailed measurements of sulfur metabolism.

scholarly journals Effect of different ambient temperatures on reproductive outcome and wellbeing of lactating females in two mouse strains

2021 ◽  
Author(s):  
Thomas Kolbe ◽  
Caroline Lassnig ◽  
Andrea Poelzl ◽  
Rupert Palme ◽  
Kerstin Elisabeth Auer ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Reproductive Performance ◽  
Mouse Strains ◽  
Stress Hormone ◽  
Ambient Temperatures ◽  
Reduced Body ◽  
Lactating Females ◽  
Corticosterone Metabolites ◽  
And Control ◽  
Fecal Corticosterone Metabolites

Ambient temperature is an important non-biotic environmental factor influencing immunological and oncological parameters in laboratory mice. It is under discussion which temperature is more appropriate and whether the commonly used room temperature in rodent facilities of about 21°C represents a chronic cold stress or the 30°C of the thermoneutral zone constitutes heat stress for the animals. In this study we selected the physiological challenging period of lactation to investigate the influence of a cage temperature of 20°C, 25°C, and 30°C, respectively, on reproductive performance and stress hormone levels in two frequently used mouse strains. We found that more pups were weaned from B6D2F1 hybrids compared to C57BL/6N mothers and that the number of weaned pups was strongly reduced if mothers of both strains were kept at 30°C. Furthermore, at 30°C mothers and pups showed reduced body weight at weaning and offspring had longer tails. Despite pronounced temperature effects on reproductive parameters, we did not find any impact on adrenocortical activity in breeding and control mice. Independent of the ambient temperature however, we found that females raising pups showed elevated levels of fecal corticosterone metabolites (FCMs) compared to controls. Increased levels of stress hormone metabolites were measured specially around birth and during the third week of lactation. Our results provide no evidence for reduced or improved wellbeing of lactating mice at different ambient temperatures, but we found that a 30°C cage temperature impairs reproductive performance.

scholarly journals Influence of Ambient Temperature on Radiative and Convective Heat Dissipation Ratio in Polymer Heat Sinks

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2286
Author(s):  
Jan Kominek ◽  
Martin Zachar ◽  
Michal Guzej ◽  
Erik Bartuli ◽  
Petr Kotrbacek
Keyword(s):  
Heat Transfer ◽  
Ambient Temperature ◽  
Convective Heat ◽  
Heat Dissipation ◽  
High Surface ◽  
Heat Sinks ◽  
Fourth Power ◽  
Molding Process ◽  
Ambient Temperatures ◽  
University Of Technology

Miniaturization of electronic devices leads to new heat dissipation challenges and traditional cooling methods need to be replaced by new better ones. Polymer heat sinks may, thanks to their unique properties, replace standardly used heat sink materials in certain applications, especially in applications with high ambient temperature. Polymers natively dispose of high surface emissivity in comparison with glossy metals. This high emissivity allows a larger amount of heat to be dissipated to the ambient with the fourth power of its absolute surface temperature. This paper shows the change in radiative and convective heat transfer from polymer heat sinks used in different ambient temperatures. Furthermore, the observed polymer heat sinks have differently oriented graphite filler caused by their molding process differences, therefore their thermal conductivity anisotropies and overall cooling efficiencies also differ. Furthermore, it is also shown that a high radiative heat transfer leads to minimizing these cooling efficiency differences between these polymer heat sinks of the same geometry. The measurements were conducted at HEATLAB, Brno University of Technology.

scholarly journals Insufficient Stability of Clavulanic Acid in Widely Used Child-Appropriate Formulations

Antibiotics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 225
Author(s):  
Ines Mack ◽  
Mike Sharland ◽  
Janneke M. Brussee ◽  
Sophia Rehm ◽  
Katharina Rentsch ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Clavulanic Acid ◽  
Storage Conditions ◽  
Essential Medicines ◽  
Active Components ◽  
Middle Income ◽  
Ambient Temperatures ◽  
Essential Medicines List ◽  
Dispersible Tablets ◽  
The Stability

Amoxicillin-clavulanic acid (AMC) belongs to the WHO Essential Medicines List for children, but for optimal antimicrobial effectiveness, reconstituted dry powder suspensions need to be stored in a refrigerated environment. Many patients in low- and middle-income countries who are sold AMC suspensions would be expected not to keep to the specified storage conditions. We aimed to assess the stability of both ingredients in liquid formulations and dispersible tablets, combined with nationally representative data on access to appropriate storage. Degradation of amoxicillin (AMX) and clavulanic-acid (CLA) was measured in suspensions and dispersible tablets commercially available in Switzerland at different ambient temperatures (8 °C vs. 28 °C over 7 days, and 23 °C vs. 28 °C over 24 h, respectively). Data on access to refrigeration and electricity were assessed from the USAID-funded Demographic and Health Survey program. In suspensions, CLA degraded to a maximum of 12.9% (95% CI −55.7%, +29.9%) at 8°C and 72.3% (95% CI −82.8%, −61.8%) at a 28 °C ambient temperature during an observation period of 7 days. Dispersible tablets were observed during 24 h and CLA degraded to 15.4% (95% CI −51.9%, +21.2%) at 23 °C and 21.7% (−28.2%, −15.1%) at a 28 °C ambient temperature. There is relevant degradation of CLA in suspensions during a 7-day course. To overcome the stability challenges for all active components, durable child-appropriate formulations are needed. Until then, prescribers of AMC suspensions or pharmacists who sell the drug need to create awareness for the importance of proper storage conditions regarding effectiveness of both antibiotics and this recommendation should be reflected in the WHO Essential Medicines List for children.

scholarly journals Phase separation during blood spreading

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Houssine Benabdelhalim ◽  
David Brutin
Keyword(s):  
Phase Separation ◽  
Relative Humidity ◽  
Whole Blood ◽  
Crime Scene ◽  
Blood Pool ◽  
Ambient Temperatures ◽  
Surrounding Environment ◽  
Crime Scene Investigators ◽  
Almost All ◽  
Pool Area

AbstractBlood pools can spread on several types of substrates depending on the surrounding environment and conditions. Understanding the influence of these parameters on the spreading of blood pools can provide crime scene investigators with useful information. The focus of the present study is on phase separation, that is, when the serum spreads outside the main blood pool. For this purpose, blood pools with constant initial masses on wooden floors that were either varnished or not were created at ambient temperatures of $$21~^{\circ }\hbox {C}$$ 21 ∘ C , $$29~^{\circ }\hbox {C}$$ 29 ∘ C , and $$37~^{\circ }\hbox {C}$$ 37 ∘ C with a relative humidity varying from 20 to 90%. The range $$21~^{\circ }\hbox {C}$$ 21 ∘ C to $$37~^{\circ }\hbox {C}$$ 37 ∘ C covers almost all worldwide indoor cases. The same whole blood from the same donor was used for all experiments. As a result, an increase in relative humidity was found to result in an increase in the final pool area. In addition, at the three different experimental temperatures, the serum spread outside the main pool at relative humidity levels above 50%. This phase separation is more significant on varnished substrates, and does not lead to any changes in the drying morphology. This phenomenon is explained by the competition between coagulation and evaporation.

Ambient temperature effects on physiological traits of white-tailed deer

1975 ◽  
Vol 53 (6) ◽  
pp. 679-685 ◽  
Author(s):  
J. B. Holter ◽  
W. E. Urban Jr. ◽  
H. H. Hayes ◽  
H. Silver ◽  
H. R. Skutt
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Energy Expenditure ◽  
Ambient Temperature ◽  
Temperature Effects ◽  
Temperature Changes ◽  
Wind Chill ◽  
Ambient Temperatures ◽  
Energy Equilibrium ◽  
Body Energy

Six adult white-tailed deer (Odocoileus virginianus borealis) were exposed to 165 periods of 12 consecutive hours of controlled constant ambient temperature in an indirect respiration calorimeter. Temperatures among periods varied from 38 to 0 (summer) or to −20C (fall, winter, spring). Traits measured were energy expenditure (metabolic rate), proportion of time spent standing, heart rate, and body temperature, the latter two using telemetry. The deer used body posture extensively as a means of maintaining body energy equilibrium. Energy expenditure was increased at low ambient temperature to combat cold and to maintain relatively constant body temperature. Changes in heart rate paralleled changes in energy expenditure. In a limited number of comparisons, slight wind chill was combatted through behavioral means with no effect on energy expenditure. The reaction of deer to varying ambient temperatures was not the same in all seasons of the year.

The Long-Term Stability in Whole Blood of 14 Commonly-Requested Hormone Analytes

1994 ◽  
Vol 31 (6) ◽  
pp. 561-565 ◽  
Author(s):  
M J Diver ◽  
J G Hughes ◽  
J L Hutton ◽  
C R West ◽  
L J Hipkin
Keyword(s):  
Ambient Temperature ◽  
Whole Blood ◽  
Great Majority ◽  
Red Cells ◽  
Clinical Interpretation ◽  
Term Stability ◽  
Long Term Stability ◽  
Plasma Hormones

Concentrations of 14 commonly-requested plasma hormones were measured in octuplicate in each of six subjects to determine their stability when unseparated from red cells for periods up to 1 week. Most of the analytes were stable when stored in this way and although statistically significant changes were recorded, in the great majority of cases the changes seen would have no bearing on the clinical interpretation of the result. In the light of these findings, we would confidently report results of analyses for these hormones in plasma that had remained in contact with red cells at ambient temperature for long periods of time.

Enhancement of iron availability by some organic materials

1979 ◽  
Vol 93 (1) ◽  
pp. 115-120 ◽  
Author(s):  
A. A. Parsa ◽  
A. Wallace ◽  
J. P. Martin
Keyword(s):  
Calcareous Soil ◽  
Dry Matter ◽  
Organic Materials ◽  
Iron Availability ◽  
Lawsonia Inermis ◽  
Plant Materials ◽  
Phenolic Substances ◽  
And Control ◽  
Layer Chromatography ◽  
Positive Effect

SUMMARYIn a preliminary laboratory experiment in Iran, not reported here, 5 out of 30 plant materials incorporated into a highly calcareous soil had a positive effect on increasing the DTPA- (diethylenetriaminepentaacetic acid)-extractable Fe and all except one significantly increased the vegetative growth of sorghum. The plant materials included Lawsonia inermis L., Malva silvestris L., Zyzyphus nummularia Wak. and Lavandula carnopifolia L. A glasshouse study was repeated with two California soils pretreated with 0·5% Fe2O3 to determine if these organic materials have practical value in making Fe available to plants. A calcareous, Fe-deficient Hacienda (fine-loamy, mixed, thermic aquic natrargid) and a non-calcareous Yolo (fine-silty, mixed, non-acid, thermic typic xerothents). The previously mentioned organic materials and Laminaria saccharina L. (Lamour) were incorporated into the soils at two rates, 15000 and 20000μg/g, as air dry and in ash form. An adequate supply of major and micronutrients other than Fe was ensured. Other treatments included 5 μg Fe/g as FeSO4, Fe-138 chelate and control. All of the plant materials with the exception of L. carnopifolia significantly increased dry-matter yield and Fe, Zn, Cu and Mn uptake by sorghum in the Hacienda soil. In the Yolo soil the above were not significant. Thin-layer chromatography of the extracts of the plant materials revealed the presence of significant quantities of phenolic substances.

scholarly journals Effect of Yeast-Fermented Citrus Pulp as a Protein Source on Nutrient Intake, Digestibility, Nitrogen Balance and In Situ Digestion Kinetics in Nili Ravi Buffalo Bulls

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1713
Author(s):  
Muhammad Awais ◽  
Muhammad Sharif ◽  
Khurram Ashfaq ◽  
Amjad Islam Aqib ◽  
Muhammad Saeed ◽  
...  
Keyword(s):  
Nitrogen Balance ◽  
Nutrient Intake ◽  
Dry Matter ◽  
Experimental Period ◽  
Nutrient Digestibility ◽  
Protein Source ◽  
Cell Protein ◽  
Citrus Pulp ◽  
Digestion Kinetics

A study was carried out to evaluate the effect of single cell protein (SCP) supplement as a protein source on nutrient intake, digestibility, nitrogen balance and in situ digestion kinetics in four Nili Ravi buffalo bulls. Four iso-caloric and iso-nitrogenous concentrates containing 3, 6, 9 and 12% of Saccharomyces cerevisiae-fermented citrus pulp were formulated. All animals were fed a ration with a concentrate/forage ratio of 50:50. Diets were provided ad libitum twice a day as a total mixed ration in a 4 × 4 Latin Square Design. Each experimental period lasted 3 weeks while the overall study 12 weeks. The first 2 weeks of each experimental period were used as adaptation period while the third week as collection period. Chemical composition of fermented citrus pulp appeared as an excellent source of protein. No significant difference was observed on dry matter intake, digestibility of nutrients and SCP among all the treatments. Moreover, no significant effect was observed on ruminal pH and ammonia nitrogen at different times. Rate of disappearance and lag time of in situ dry matter digestion kinetics remained nonsignificant regardless of SCP percentage. Based on results of similar nutrients intake, nutrient digestibility, and ruminal parameters it is concluded that SCP could be used in the concentrate diet of ruminant up to 12%. Furthermore, the SCP has the potential of an alternative protein source in animal diet formulation.

Change in the Properties of a Lead-acid Battery Depending on the Cycling Speed and the Ambient Temperature

2021 ◽  
Vol 105 (1) ◽  
pp. 119-134
Author(s):  
Jana Zimáková ◽  
Petr Baca ◽  
Martin Langer ◽  
Tomáš Binar
Keyword(s):  
Ambient Temperature ◽  
High Temperatures ◽  
Room Temperature ◽  
Lead Acid Battery ◽  
Ambient Temperatures ◽  
Lead Acid Batteries ◽  
Temperature Dependences ◽  
Cycling Speed ◽  
Lead Acid

This work deals with lead-acid batteries, their properties and individual types that are available on the market. The temperature dependences of the battery parameters at different ambient temperatures and at different discharging and charging modes are measured. 6 batteries are tested at different charging currents, which provides information about their behavior both during discharge and at the time of charging. During the experiments, testing is not only performed at room temperature, but the batteries are also exposed to high temperatures up to 75 °C.

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