Cold climate and cold temperature induced changes in the heat production and thermal insulation of sheep

1969 ◽  
Vol 47 (6) ◽  
pp. 553-562 ◽  
Author(s):  
A. J. F. Webster ◽  
A. M. Hicks ◽  
F. L. Hays
Keyword(s):  
Thermal Insulation ◽  
Heat Production ◽  
Metabolic Response ◽  
Ambient Air ◽  
Cold Climate ◽  
Cold Temperature ◽  
Control Group ◽  
Cold Temperatures ◽  
Induced Changes ◽  
Persistent Elevation

Heat production and thermal insulation were measured in three groups of sheep, control, outdoor, and indoor, which were exposed to the effects of season, cold climate, and cold temperature respectively. The experiment was for 24 weeks, from November 1967 to April 1968. Sheep in the control, outdoor, and indoor groups gained 16.2, 10.0, and 14.9 kg respectively. Average feed intake in both control and outdoor groups was 2.65 kg hay/100 kg sheep per day. Food intake was highest in the indoor group and was inversely related to ambient air temperature. Resting heat production was constant throughout in the control group but increased with time in the outdoor group. Resting heat production in indoor sheep was related to intensity of prior cold exposure. Wool growth and thermal insulation did not differ significantly between groups. Critical temperature for the outside group fell from −15 °C in week 4 to −35 °C in week 20. After these trials, all sheep were shorn. The heat production of the shorn indoor group at −30 °C was greater, and that of the outdoor group was less than that of the controls. The results suggest that, in sheep, acclimation to cold temperatures induces rapid, brief increases in resting heat production and summit metabolism. Acclimatization to cold climates slowly induces a persistent elevation in resting heat production, but appears to reduce the initial metabolic response to an intense cold stimulus.

scholarly journals Geographic variation in larval cold tolerance and exposure across the invasion front of a widely established forest insect

2021 ◽  
Author(s):  
Petra Hafker ◽  
Lily M Thompson ◽  
Dylan Parry ◽  
Jonathan A Walter ◽  
Kristine L Grayson
Keyword(s):  
Cold Tolerance ◽  
Thermal Tolerance ◽  
Sublethal Effects ◽  
Single Point ◽  
Cold Climate ◽  
Cold Temperature ◽  
Growth Responses ◽  
Forest Insect ◽  
Cold Temperatures ◽  
Chill Coma

As the global climate changes, high and low temperature extremes can drive changes in species distributions. Across the range of a species, thermal tolerance can experience plasticity and may undergo selection, shaping resilience to temperature stress. In this study, we measured variation in the lower thermal tolerance of early instar larvae of an invasive forest insect, Lymantria dispar dispar L. (Lepidoptera: Erebidae), using populations sourced from the climatically diverse invasion of the Eastern United States. In two chill coma recovery experiments, we recorded recovery time following a period of exposure to a non-lethal cold temperature. A third experiment quantified growth responses after chill coma recovery to evaluate sublethal effects. Our results indicate that cold tolerance is linked to regional climate, with individuals from cold climate populations recovering faster from chill coma. While this geographic gradient is seen in many species, detecting this pattern is notable for an introduced species founded from a single point-source introduction. We demonstrate that the cold temperatures used in our experiments occur in nature from cold snaps after spring hatching, but negative impacts to growth and survival appear low. We expect that population differences in cold temperature performance manifest more from differences in temperature-dependent growth than acute exposure. Evaluating intraspecific variation in cold tolerance increases our understanding of the role of climatic gradients on the physiology of an invasive species, and contributes to tools for predicting further expansion.

Winterization Needs for Platforms Operating in Low Temperature Environment

2013 ◽  
Author(s):  
Ove Tobias Gudmestad ◽  
Yaroslav Efimov ◽  
Konstantin Kornishin
Keyword(s):  
Low Temperature ◽  
Oil And Gas ◽  
Ambient Air ◽  
Cold Climate ◽  
Main Concern ◽  
Common Belief ◽  
Cold Temperatures ◽  
Air Temperatures ◽  
Partial Cover ◽  
Exploration And Production

According to a common belief which is shared by a lot of specialists from different areas petroleum business goes far into the offshore. One of the most promising regions of hydrocarbon production in the nearest future is stated to be Arctic region. But this surprisingly rich region is also happens to be one of the toughest and challenging areas to operate. Due to extremely cold air temperatures, strong winds, presence of ice and other harsh physical and climatic conditions safety requirements and technological demands call for new conceptual solutions for constructions that are panned to be used in Arctic. For exploration and production facilities in the cold climate the following aspects are essential: personnel and environment safety, as well as uninterrupted fail-safe technological process. In cold climates the main concern goes to low ambient air temperatures and presence/accretion of ice. Cold temperatures affect both personnel and equipment on the platform. To protect platform from influence of cold temperatures special heated covers can be used. This solution has certain concerns with heating, ventilation and air conditioning (HVAC) and energy supply systems. Yet another way here might be partial cover of equipment with special shelters and climatic modifications. Ice is considered to be the second limiting factor: sea ice that requires ICE CLASS vessels or specially designed platforms (not to mention ice bergs) and icing that endangers all unprotected systems on the platform. To deal with these threats different strategies might be used but there is still no one answer. Every case is some kind of unique when speaking about Arctic constructions. Ice-induced vibrations observed on platforms in the Bohay bay that haven’t been studied or even considered is a good example. Winterization for platforms is not fully developed yet and requires deeper research. The paper anticipates different codes and standards for offshore oil and gas facilities to be designed to operate in low temperature environments (American Bureau of Shipping ABS, Russian Maritime Register of Shipping, Det Norske Veritas DNV, International Organization for Standardization ISO, Canadian Standards Association CSA). These rules are compared against the experience of several major oil and gas operators and service companies gained during studies of conceptual design for Arctic exploration and production constructions at pre-FEED and FEED stages. The most important winterization concerns are highlighted and scrutinized.

scholarly journals Phenology and Winter Hardiness of Cold-climate Grape Cultivars and Advanced Selections in Iowa Climate

2019 ◽  
Vol 29 (6) ◽  
pp. 906-922 ◽  
Author(s):  
James A. Schrader ◽  
Diana R. Cochran ◽  
Paul A. Domoto ◽  
Gail R. Nonnecke
Keyword(s):  
Low Temperature ◽  
The United States ◽  
Cold Climate ◽  
Cold Temperature ◽  
Heat Accumulation ◽  
Wine Production ◽  
Cold Temperatures ◽  
Temperature Damage ◽  
Grape Cultivars

The popularity of grape (Vitis sp.) and wine production in the upper midwest region of the United States is increasing steadily. The development of several cold-climate, interspecific-hybrid grape cultivars (northern hybrids) since the 1980s has improved the probability of success for both new and established vineyards in this area of the country, but long-term data describing the performance of these cultivars in midwestern U.S. climates are needed to both aid growers in their choice of cultivars and to provide them with information about factors important in their management. We characterized the long-term winterhardiness and annual phenology of 12 cold-climate northern hybrid grape cultivars (two established cultivars, five newer cultivars, and five advanced selections) grown in a randomized and replicated field plot in central Iowa, an area that offers a warm growing season and very cold dormant season for grape culture. The established cultivars included in the study were Frontenac and St. Croix. The newer cultivars evaluated were Arandell, Corot noir, La Crescent, Marquette, and Petit Ami, and the advanced selections were MN 1189, MN 1200, MN 1220, MN 1235, and MN 1258. The grape trial was established in 2008, and vines were evaluated from 2011 through 2017 for annual timing of budbreak, bloom, veraison, and harvest, as well as winter survival of vines and primary buds. As a group, the northern hybrids in our trial showed good winterhardiness of vines but variable hardiness of primary buds across the six winters, which ranged from warmer than average to much colder than average. In Iowa climate, buds of northern hybrids were generally most vulnerable to cold temperature damage from late-winter (March) low-temperature events or from extreme midwinter low-temperature events. The bud hardiness of individual cultivars ranged from very hardy (Frontenac, Marquette, and MN 1235) to poor hardiness (Arandell, Corot noir, Petit Ami, and MN 1189), with all 12 cultivars showing good bud survival during Iowa winters that were warmer than average, but the less-hardy cultivars showing poor bud survival during winters that were colder than average. Evaluations of phenology revealed that heat accumulation measured in growing degree days with a threshold of 50 °F was not a reliable index for predicting the timing of annual developmental stages for the cultivars we tested. Our results indicate that northern hybrids rely on other factors in addition to heat accumulation for guiding annual development, and that factors such as photoperiod likely have a strong influence on phenological timing during seasons with unusual weather patterns. We determined that none of the cultivars were vulnerable to cold temperature damage to fruit before harvest in Iowa’s climate, but that three of the cultivars (Arandell, Marquette, and MN 1235) were highly vulnerable to shoot damage from spring freeze events, and four others (Corot noir, La Crescent, MN 1200, and MN 1220) were moderately vulnerable to cold damage to shoots in spring. An itemized summary of the relative hardiness, vulnerabilities, and timing of phenological stages of the 12 cultivars is provided to aid growers in selection and management of grape cultivars for Iowa climate. Based on hardiness and phenology, four of these cultivars (Frontenac, MN 1258, MN 1220, and MN 1200) have the lowest risk of issues related to cold temperatures.

scholarly journals Effects of different thermal insulation methods on the nasopharyngeal temperature in patients undergoing laparoscopic hysterectomy: a prospective randomized controlled trial

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Guanyu Yang ◽  
Zefei Zhu ◽  
Hongyu Zheng ◽  
Shifeng He ◽  
Wanyue Zhang ◽  
...  
Keyword(s):  
Thermal Insulation ◽  
Primary Outcome ◽  
Controlled Trial ◽  
Laparoscopic Hysterectomy ◽  
Control Group ◽  
Prospective Randomized Controlled Trial ◽  
Warming Blanket ◽  
Group A ◽  
Insulation Effect ◽  
Group B

Abstract Background This study explored the comparison of the thermal insulation effect of incubator to infusion thermometer in laparoscopic hysterectomy. Methods We assigned 75 patients enrolled in the study randomly to three groups: Group A: Used warming blanket; group B: Used warming blanket and infusion thermometer; group C: Used warming blanket and incubator. The nasopharyngeal temperature at different time points during the operation served as the primary outcome. Results The nasopharyngeal temperature of the infusion heating group was significantly higher than that of the incubator group 60 min from the beginning of surgery (T3): 36.10 ± 0.20 vs 35.81 ± 0.20 (P<0.001)90 min from the beginning of surgery (T4): 36.35 ± 0.20 vs 35.85 ± 0.17 (P<0.001). Besides, the nasopharyngeal temperature of the incubator group was significantly higher compared to that of the control group 60 min from the beginning of surgery (T3): 35.81 ± 0.20 vs 35.62 ± 0.18 (P<0.001); 90 min from the beginning of surgery (T4): 35.85 ± 0.17 vs 35.60 ± 0.17 (P<0.001). Regarding the wake-up time, that of the control group was significantly higher compared to the infusion heating group: 24 ± 4 vs 21 ± 4 (P = 0.004) and the incubator group: 24 ± 4 vs 22 ± 4 (P = 0.035). Conclusion Warming blanket (38 °C) combined infusion thermometer (37 °C) provides better perioperative thermal insulation. Hospitals without an infusion thermometer can opt for an incubator as a substitute. Trial registration This trial was registered with ChiCTR2000039162, 20 October 2020.

Study on Kidney Function in Female Workers Exposed to Perchlorethylene

1990 ◽  
Vol 9 (6) ◽  
pp. 377-380 ◽  
Author(s):  
A. Vyskočil ◽  
S. Emminger ◽  
J. Tejral ◽  
Z. Fiala ◽  
E. Ettlerova ◽  
...  
Keyword(s):  
Urinary Excretion ◽  
Biochemical Parameters ◽  
Renal Damage ◽  
Ambient Air ◽  
Exposed Group ◽  
Control Group ◽  
Total Proteins ◽  
Dry Cleaning ◽  
Female Workers ◽  
Occupationally Exposed

1 Biochemical markers of kidney damage were examined in 16 female workers chronically exposed to tetrachlorethylene (TCE) in five dry-cleaning shops. The results were compared with those obtained in 13 females non-occupationally exposed to organic solvents. 2 The intensity of exposure was monitored by personal environmental monitoring. The time-weighed average exposure to TCE amounted to 157 mg m-3 (range 9-799 mg m-3). A satisfactory agreement was found between the concentration of TCE in ambient air sampled with the charcoal tube method and with a passive dosimeter. 3 The urinary excretion of lysozyme was increased in the exposed group. No difference was found in the urinary excretion of albumin, β2-microglobulin, lactate dehydrogenase, total proteins or glucose. The prevalence of abnormal values of biochemical parameters in the exposed group did not differ from that observed in the control group. No correlation was found between the level of TCE exposure and biochemical parameters. 4 The present study suggests that chronic exposure to TCE does not lead to renal damage.

A Study on the Effect of Samoa Extract (Cleome droserifolia) on Sperm Quality in Male Albino Rats Exposed to Pyrethroid

2021 ◽  
pp. 39-45
Author(s):  
Nura I. Al-Zail ◽  
Salah F. Kamies
Keyword(s):  
Sperm Quality ◽  
Group Iv ◽  
Male Rats ◽  
Control Group ◽  
Albino Rats ◽  
Protective Agent ◽  
Group V ◽  
Group Iii ◽  
Group I ◽  
Induced Changes

Pyrethroid cyhalothrin (PC) is an insecticide that is used worldwide for pest control in agriculture and household use. Samoa extract (SE) is a potent antioxidant protecting cells from oxidative stress. The present study investigates the protective and therapeutic effect of SE on PC-induced changes in sperm quality in male rats. Fifty adult male albino rats were divided into five groups: group I: served as control; group II: received PC i.p. only (6.2 mg/kg b.wt.); group III: received SE only (100 mg/kg b.wt., p.o.) for eight weeks; group IV: received SE as a protective agent daily for eight weeks, then followed by the administration of PC (i.p.) three times a week for two weeks; group V: exposed to PC (i.p.) three times a week for two weeks, then treated with the SE daily for 8 weeks. Results showed that PC caused markedly impaired sperm quality (a count, viability, motility, and abnormality). Compared to PC-treated animals, SE in the protective group markedly restored the alteration of sperm indices. However, SE in the curative group was found to be less effective in restoring PC-induced alterations. In conclusion, the data of this study revealed that the SE as a protective agent is more effective than as a therapeutic agent. Keywords: Samoa; Pyrethroid; Sperm quality; Rat

Physical fitness and thermoregulatory reactions in a cold environment in men

1988 ◽  
Vol 65 (5) ◽  
pp. 1984-1989 ◽  
Author(s):  
J. H. Bittel ◽  
C. Nonotte-Varly ◽  
G. H. Livecchi-Gonnot ◽  
G. L. Savourey ◽  
A. M. Hanniquet
Keyword(s):  
Physical Fitness ◽  
Cold Stress ◽  
Heat Production ◽  
Ambient Air ◽  
Metabolic Heat Production ◽  
Adult Males ◽  
Fitness Level ◽  
Metabolic Heat ◽  
Air Temperatures ◽  
Thermoregulatory Reactions

The relationship between the physical fitness level (maximal O2 consumption, VO2max) and thermoregulatory reactions was studied in 17 adult males submitted to an acute cold exposure. Standard cold tests were performed in nude subjects, lying for 2 h in a climatic chamber at three ambient air temperatures (10, 5, and 1 degrees C). The level of physical fitness conditioned the intensity of thermoregulatory reactions to cold. For all subjects, there was a direct relationship between physical fitness and 1) metabolic heat production, 2) level of mean skin temperature (Tsk), 3) level of skin conductance, and 4) level of Tsk at the onset of shivering. The predominance of thermogenic or insulative reactions depended on the intensity of the cold stress: insulative reactions were preferential at 10 degrees C, or even at 5 degrees C, whereas colder ambient temperature (1 degree C) triggered metabolic heat production abilities, which were closely related to the subject's physical fitness level. Fit subjects have more efficient thermoregulatory abilities against cold stress than unfit subjects, certainly because of an improved sensitivity of the thermoregulatory system.

Prevention of Methacholine-induced Changes in Respiratory Mechanics in Piglets

1997 ◽  
Vol 87 (3) ◽  
pp. 585-590 ◽  
Author(s):  
Walid Habre ◽  
Johannes H. Wildhaber ◽  
Peter D. Sly
Keyword(s):  
Respiratory Mechanics ◽  
Minimum Alveolar Concentration ◽  
Volatile Anesthetic ◽  
Lung Compliance ◽  
Control Group ◽  
Alveolar Pressure ◽  
Insufficient Information ◽  
Volatile Anesthetic Agent ◽  
Airway Opening ◽  
Induced Changes

Background Sevoflurane is a new volatile anesthetic agent that may be a useful alternative to halothane for anesthesia in children. However, there is insufficient information about its effects on respiratory mechanics, particularly in the presence of constrictor stimuli. Methods Eighteen piglets had anesthesia induced and maintained with either pentobarbital (control: n = 8), 1 minimum alveolar concentration (MAC) sevoflurane (sevo: n = 5), or 1 MAC halothane (halo: n = 5). Pressure, flow, and volume were measured at the airway opening and used to calculate lung compliance (C(L)) and resistance (R(L)). Resistance was partitioned into airway (Raw) and parenchymal (Vti) components using alveolar pressure. Methacholine was infused intravenously in a dose sufficient (15 microg x kg(-1) x h(-1)) to approximately double R(L). Results The increase in R(L) seen in the control group was almost entirely due to an increase in Vti. Sevoflurane and halothane prevented the increase in R(L) and Vti (both P &lt; 0.02) and the decrease in C(L) (both P &lt; 0.02). Conclusions Sevoflurane and halothane can prevent methacholine-induced changes in lung function.

scholarly journals Reactive Oxygen Species and the Redox-Regulatory Network in Cold Stress Acclimation

Antioxidants ◽  
2018 ◽  
Vol 7 (11) ◽  
pp. 169 ◽  
Author(s):  
Anna Dreyer ◽  
Karl-Josef Dietz
Keyword(s):  
Reactive Oxygen Species ◽  
Cold Stress ◽  
Regulatory Network ◽  
Chilling Stress ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Reactive Oxygen ◽  
Cold Climate ◽  
Oxygen Species ◽  
Cold Temperatures ◽  
Stress Acclimation

Cold temperatures restrict plant growth, geographical extension of plant species, and agricultural practices. This review deals with cold stress above freezing temperatures often defined as chilling stress. It focuses on the redox regulatory network of the cell under cold temperature conditions. Reactive oxygen species (ROS) function as the final electron sink in this network which consists of redox input elements, transmitters, targets, and sensors. Following an introduction to the critical network components which include nicotinamide adenine dinucleotide phosphate (NADPH)-dependent thioredoxin reductases, thioredoxins, and peroxiredoxins, typical laboratory experiments for cold stress investigations will be described. Short term transcriptome and metabolome analyses allow for dissecting the early responses of network components and complement the vast data sets dealing with changes in the antioxidant system and ROS. This review gives examples of how such information may be integrated to advance our knowledge on the response and function of the redox regulatory network in cold stress acclimation. It will be exemplarily shown that targeting the redox network might be beneficial and supportive to improve cold stress acclimation and plant yield in cold climate.

scholarly journals THE EFFECT OF ADDITION OF SUCROSE SOLUTION ON THE ANTIBACTERIAL ACTIVITIES OF GREEN GRASS JELLY EXTRACT SINBIOTIC BEVERAGES DURING STORAGE IN COLD TEMPERATURE

Agric ◽  
2019 ◽  
Vol 31 (1) ◽  
pp. 53-66
Author(s):  
Samsul Rizal ◽  
Julfi Restu Amelia ◽  
Suharyono A S
Keyword(s):  
Antibacterial Activity ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Pathogenic Bacteria ◽  
Sucrose Solution ◽  
Cold Temperature ◽  
Diffusion Method ◽  
Total Acid ◽  
Cold Temperatures ◽  
Significant Difference

Sinbiotic drinks have a very acidic taste, so it is necessary to add sucrose solution to get the best taste. This study aims to determine the effect of adding 65% (v/v) sucrose solution to changes in antibacterial activity of green grass jelly synbiotic drinks during storage in cold temperatures. The finished green grass jelly synbiotic product was given two different treatments, namely the product without the addition of sucrose solution and product with the addition of 10% (v/v) of 65% (b/v) sucrose solution. The product was stored for 28 days at a cold temperature of ± 10oC. Observations were carried out every 7 days for antibacterial activity, pH, total acid, and total lactic acid bacteria. Antibacterial activity was evaluated using the agar diffusion method against pathogenic bacteria including Staphylococcus aureus, Salmonella sp., Bacillus cereus, and Eschericia coli. The results showed that the antibacterial activity, pH, and total lactic acid bacteria of green grass jelly synbiotic drinks both without and with the addition of 65% (b/v) sucrose as much as 10% (v/v) reduced during storage at cold temperatures, while total acid increases. There was no significant difference between the antibacterial activity and the characteristics of the green grass jelly synbiotic drink given 65% sucrose solution and without the addition of 65% sucrose solution. Thus the study concluded that the addition of 65% sucrose solution to increase the preference for the product did not significantly affect the change in antibacterial activity of the green grass jelly synbiotic beverage during storage in cold temperatures.

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