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Exposure to a cold climate is associated with an increased morbidity and mortality, but the specific mechanisms are largely unknown. People with cardiopulmonary disease and winter endurance athletes are particularly vulnerable. This study aimed to map multiple domains of airway responses to exercise in subzero temperature in healthy individuals. Thirty-one healthy subjects underwent whole-body exposures for 50 minutes on two occasions in an environmental chamber with intermittent moderate-intensity exercise in +10 °C and -10 °C. Lung function, plasma/urine CC16 , and symptoms were investigated before and after exposures. Compared to baseline, exercise in -10 °C decreased FEV1 (p=0.002), FEV1/FVC (p<0.001), and increased R20Hz (p=0.016), with no differences between exposures. Reactance increased after +10 °C (p=0.005), which differed (p=0.042) from a blunted response after exercise in -10 °C. Plasma CC16 increased significantly within exposures, without differences between exposures. Exercise in -10 °C elicited more intense symptoms from the upper airways, compared to +10 °C. Symptoms from the lower airways were few and mild. Short-duration moderate-intensity exercise in -10 °C induces mild symptoms from the lower airways, no lung function decrements or enhanced leakage of biomarkers of airway epithelial injury, and no peripheral bronchodilatation, compared to exercise in +10 °C. [ABSTRACT FROM AUTHOR]

In this study, a useful solution is proposed for assessing the safety of the ship's hull damaged by grounding in Northern Sea Route (NSR) or Arctic sea. In particular, the residual ultimate longitudinal strength of grounding damaged ship can be predicted by the grounding damage index (GDI) concept. Due to the global warming effects, the Arctic glaciers have been gradually melting, and it may bring us the new North Pole routes. However, there are uncertainties on many causes that can lead to grounding accident of the commercial vessels. In this regard, residual ultimate longitudinal strength of grounding damaged commercial ship in Arctic sea is investigated. Five (5) temperatures: room temperature (RT), −20°C, −40°C, −60°C and −80°C were adopted to consider the cold temperature effect in NSR. The Panamax class oil tanker was selected for the investigation of residual ultimate longitudinal strength of grounding damaged ship. Fifty (50) reliable damage scenarios were adopted for the evaluation of structural health by utilising Residual strength versus GDI (R-D) diagram method. From this study, a modified R-D diagram is proposed which can consider grounding damage with cold temperature effect. The obtained outcome will be useful for assessing the safety of the grounded ships in Arctic sea region by measuring the grounding damage amount and surrounding air temperature. [ABSTRACT FROM AUTHOR]

An efficient management of the newborn dairy calf around birth results in reduced rearing costs and increased future milk yield. To maintain young calves healthy and maximize performance and profit it is important to create an environment that maintain low levels of stress. Low environment temperature directly affects newborn and young calves' performance, health and survival due hypothermia. For that reason, the adaptation of the dairy calf to the cold environment is important, with body responses of primary importance. However, some strategies may also be adopted to reduce cold stress induced by heat loss. There are several ways to aid the young calf in low environmental temperature, starting immediately after birth with colostrum feeding. Besides that, factors such as adequate housing, management and nutrition, result in significantly decrease morbidity and mortality, and similar growth rates as calves in the zone of thermoneutrality. The calf physiology adaptation to cope with cold stress and the positive effect of feeding systems, resulting in greater heat production, health, and performance will be approach in this literature review. [ABSTRACT FROM AUTHOR]

We have isolated several poly 3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBH) degradable bacteria from the deep-sea sediment samples. The isolated microbes were involved into α-, γ- Proteobacteria group and the phylum Firmicutes, which were commonly diverged in the ocean environment. Four bacterial strains, Bacillus sp. MH10, Alteromonas sp. MH53, Psychrobacillus sp. PL87 and Rheinheimera sp. PL100, were selected as more active strains for the PHBH bio-degradation at high pressure and cold temperature conditions, and showed that those strains were piezotolerant up to 20–30 MPa. Our findings indicated that the PHBH could be well degraded not only in the ocean environment, but also at the deep-sea bottom, by means of those marine microorganisms. [ABSTRACT FROM AUTHOR]

People experiencing homelessness have an increased risk of cold-related injuries. This study determined the rate of emergency department (ED) visits for cold-related injuries among homeless adults and low-income controls in Toronto, Canada. Homeless individuals were recruited at shelters and meal programs. Age- and sex-matched controls living in low-income neighborhoods were selected. ED utilization was ascertained over 4-years of follow-up (2005-9) using administrative databases. A total of 16 ED visits for cold-related injuries were observed among 587 homeless men and 296 homeless women. The rate of ED visits was 6.7 (95% CI, 4.2-12.4) per 1000 person-years of observation among homeless men and 0.9 (95% CI, 0.03-5.6) among homeless women. ED visit rates were significantly higher among homeless men compared to low-income men (P < 0.001) and significantly higher among homeless men compared to homeless women (P = 0.03). Targeted public health interventions are needed to reduce the risk of cold-related injuries among people experiencing homelessness. [ABSTRACT FROM AUTHOR]

In structural analysis and design, it is essential to define the material properties associated with the targeted structural systems. When harsh environmental or operational conditions are of primary concern, the mechanical properties of materials must be quantified by considering the effects of the conditions. The aim of this study is to develop a new test database on the mechanical properties of materials for marine applications, such as mild steel, high-tensile steel, aluminium alloy 5083-O and stainless steel 304L, focusing on the effects of cold temperatures and strain rates. Discussion of the new test database refers to extant test databases where available. Moreover, test coefficients that may be useful in the existing constitutive equations for the materials are suggested and the details of the test database are documented. [ABSTRACT FROM AUTHOR]

Pilot-scale moving bed biofilm reactor (MBBR) is used to investigate the kinetics and biofilm response of municipal, tertiary nitrification at 1°C. The research demonstrates that significant rates of tertiary MBBR nitrification are attainable and stable for extended periods of operation at 1°C, with a maximum removal rate of 230 gN/m3 d at 1°C. At conventional nitrogen loading rates, low ammonia effluent concentrations below 5 mg-N/L were achieved at 1°C. The biofilm thickness and dry weight biofilm mass (massdw) were shown to be stable, with thickness values showing a correlation to the protein/polysaccharide ratio of the biofilm extracellular polymeric substances. Lastly, tertiary MBBR nitrification is shown to increase the effluent suspended solids concentrations by approximately 3 mg total suspended solids /L, with 19–60% of effluent solids being removed after 30 min of settling. The settleability of the effluent solids was shown to be correlated to the nitrogen loading of the MBBR system. [ABSTRACT FROM AUTHOR]

A 3-D module of power battery thermal management unit with phase change material is formulated. The cold start-up time of air heating is 4.2 times of phase change material heating from 243.15 to 283.15 K. The temperature difference decreases from 9.9 to 4.6°C when the thermal conductivity of the phase change material increases to five times. The heat transports from the domain near an electrode can reheat the domain away from the electrode and make the thermal energy distributing more even inside the battery. A well-designed thermal management system with phase change material is positive for power battery applying under cold temperature. [ABSTRACT FROM PUBLISHER]

The goal of this study was to investigate the potential use of moving bed biofilm reactor (MBBR) systems as ammonia removal post-treatment units for wastewater (WW) treatment lagoons that demonstrate large temperature changes throughout their operational year (1−20°C). The study was carried out over a six-month period using laboratory-scale MBBR reactors fed with incoming effluent from a full-scale lagoon. The study shows that significant average ammonia removal rates of 0.26 and 0.11 kg N/m3·d were achieved at 20°C and 1°C. The increase in the ammonia removal rates with increasing temperature from 1°C to 20°C showed a strong correlation to an applied temperature correction coefficient model. No significant accumulation of effluent nitrite was observed at 1°C or after being fed with synthetic wastewater (SWW); indicating that cold temperatures and transitions from real WW to SWW did not stress the nitrifiers. Furthermore, the study demonstrates that changes in temperature or changes from real WW to SWW do not affect the mass of biofilm attached per MBBR carrier. Hence, based on the results of this study, it is concluded that MBBR is a promising technology for post-treatment ammonia removal of WW lagoon effluent. [ABSTRACT FROM PUBLISHER]

Background. The aim of this study was to determine the effects of exposure to cold and heat on the activity of selected lysosomal enzymes as well as on the activity of the protease inhibitor, which are all considered to be markers of cellular damage. Material. Two groups of healthy volunteers were included in the study. The first group consisted of experienced winter swimmers who practiced bathing in ice-cold water once a week, while the other group was comprised of persons who had never taken part in winter swimming before. During the experiment all the participants bathed in a river with a water temperature of 0°C. The same volunteers were later subjected to a sauna bath at an air temperature of 85°C. Methods. The activity of cathepsin D, alpha-1-antitrypsin, arylsulphatase and acid phosphatase was measured in the participant's blood serum. Results. After exposure to cold water no changes in the parameters studied could be found. However, after the sauna an increase in the activity of arylsulphatase and alfa-1-antitrypsin accompanied by a decrease of cathepsin D activity could be observed. Conclusions. Winter swimming seems to have no effect on the activity of the lysosomal enzymes. By contrast, an increase of certain lysosomal enzymes after the sauna suggests that it may be deleterious to the lysosomal membranes. Furthermore it seems that regular winter swimming combined with sauna, according to hormesis theory, induces some adaptive response. [ABSTRACT FROM AUTHOR]

Isolated sympathetic ganglia from various mammalian species fire spontaneous, rhythmic discharge when exposed to low temperatures. Extracellular recording from rat, guinea pig, and rabbit superior cervical ganglia as well as dog lumbar ganglion revealed large single potentials or bursts of potentials, occurring at regular intervals, when the bath temperature was kept between 15-30°C. When the temperature was reduced below 15°C or raised above 30°C, the rhythmic discharge decreased in frequency and finally stopped. Rhythmic discharge also appeared when ganglia were treated with emetine or the K+ channel blockers, cesium and 4-aminopyridine. The frequency and amplitude of potentials and the pattern of rhythm varied from ganglion to ganglion. The single potential or rhythmic burst firing seemed to originate from a single unit or multiple discharging units, as indicated by the amplitude and frequency of the potentials in a burst. The discharge was abolished by ganglionic blocking agents or by the absence of Ca2+, suggesting a presynaptic origin. The spontaneous rhythmic discharge may be important as a support mechanism for the cardiovascular system in victims of exposure to extreme cold temperature. [ABSTRACT FROM AUTHOR]

Methyl jasmonate (MeJA) has recently been shown to act as a plant-to-bacteria signal. We tested the hypothesis that pre-induction of Rhizobium leguminosarum bv. phaseoli cells with genistein and/or MeJA would at least partially overcome the negative effects of low root zone temperature (RZT) on bean nodulation, nitrogen fixation and plant growth. Otebo bean plants were grown at constant air temperature (25 o C) and two RZT regimes (25 and 17 o C) and inoculated with R. leguminosarum bv. phaseoli pre-induced with MeJA and/or genistein. Our results indicate that low RZT inhibited nodulation, nitrogen fixation and plant growth. The plants growing at low RZT began fixing nitrogen seven days later compared to those at higher RZT. The low RZT plants had fewer nodules, lower nodule weight, less N fixation, slower plant growth, fewer leaves, smaller leaf area, and less dry matter accumulation comared to plants at a higher RZT. Rhzobium leguminosarum bv. phaseoli cells induced with genistein and/or MeJA enhanced bean nodulation, nitrogen fixation and growth at both optimum and suboptimum RZTs. The results of this study indicate that MeJA improves bean nitrogen fixation and growth at both optimum and suboptimum RZTs, and can be used alone or in combination with genistein to partially overcome the low RZT induced inhibitory effects on nodulation and nitrogen fixation. [ABSTRACT FROM AUTHOR]

The expression of the immediate early gene c-fos has been used extensively as a marker for neural activation in response to acute and chronic stressful stimuli in brain and spinal cord. The present study examined the expression of Fos protein in the brainstem nuclei of male and female gonadectomized mice in response to cold stress. Free-floating sections were processed immunohistochemically for Fos protein using standard avidin-biotin complex methods. The number of Fos-positive neurons in each nucleus was determined. Although the experiment was designed to look for gender differences, results were equivalent between females and males. After mice were exposed to a cold ambient temperature (4°C) for 2 h, elevated numbers of Fos-positive neurons were counted in the medullary gigantocellular reticular nucleus, medullary raphe nucleus, nucleus of the solitary tract and in locus coeruleus. However, no elevated expression was found in nucleus ambiguus, nor in neurons of the A1 group, nor the C2 or C3 group. Similar to rats, these results with mice reveal a widespread arousal system in the lower brainstem activated by cold stress in both genders. These findings in gonadectomized mice have set the stage for investigations following hormonal and genetic manipulations. [ABSTRACT FROM AUTHOR]

Untreated vasomotor symptoms of the menopause can have a major impact on women at work. Recent recommendations advocate modification of the working environment, including adequate air-conditioning, to help relieve these symptoms. However, this may cause discomfort for work colleagues. We report the case of a 40-year-old woman with cold urticaria. Cold urticaria is a serious, potentially life-threatening condition. Our patient's symptoms were exacerbated when her postmenopausal work colleagues turned the air-conditioner temperature down to relieve their vasomotor symptoms. [ABSTRACT FROM AUTHOR]

In structural analysis and design, it is essential to define the material properties associated with the targeted structural systems. When harsh environmental or operational conditions are of primary concern, the mechanical properties of materials must be quantified by considering the effects of the conditions. The aim of this study is to develop a new test database on the mechanical properties of materials for marine applications, such as mild steel, high-tensile steel, aluminium alloy 5083-O and stainless steel 304L, focusing on the effects of cold temperatures and strain rates. Discussion of the new test database refers to extant test databases where available. Moreover, test coefficients that may be useful in the existing constitutive equations for the materials are suggested and the details of the test database are documented. [ABSTRACT FROM PUBLISHER]