Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cold Climate”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 415 records · Page 23Linked to original sources

[Strategies and approaches of ecological and economical construction in the ecotone between agriculture and animal husbandry of north China].

After a century's exploitation on agriculture, the agroecosystem in the ecotone between agriculture and animal husbandry of North China has gone on a close and consumptive state, and the soil resources has suffered from desertization, alkalization and degradation. The deterioration of soil resources and eco-environment has threatened the ecological security of the regions in Beijing, Tianjin and North China. The strategies of promoting the ecological and economical development in the ecotone should include building up an opening production structure of agriculture and animal husbandry to input artificial energy from the social system, and organizing a cooperative production on agriculture and animal husbandry by exchanging products between the close regions to gain their profits. Based on the various objectives of the local farmers and the nation in the ecological rehabilitation, and the adverse succession of the ecosystem and economics, some technological approaches for making a breakthrough of economic and ecological construction were put forward, e.g., building up a suitable pattern of arbor or shrub intercropped with artificial pasture to protect soil against wind erosion, developing vegetable production adapted to the cold climate, and raising live stocks with corn residues from agricultural zone of North China, etc..

Agriculture↗

Psychrophilic versus psychrotolerant bacteria--occurrence and significance in polar and temperate marine habitats.

The numerical dominance and ecological role of psychrophilic bacteria in bottom sediments, sea ice, surface water and melt pools of the polar oceans were investigated using isolates, colony forming units (CFU) and metabolic activities. All sediment samples of the Southern Ocean studied showed a clear numerical dominance of cold-loving bacteria. In Arctic sediments underlying the influence of cold polar water bodies psychrophiles prevailed also but they were less dominant in sediments influenced by the warm Atlantic Water. A predominance of psychrophiles was further found in consolidated Antarctic sea ice as well as in multiyear Arctic sea ice and in melt pools on top of Arctic ice floes. A less uniform adaptation response was, however, met in polar surface waters. In the very northern part of the Fram Strait (Arctic Ocean) we found bacterial counts and activities at 1 degree C exceeding those at 22 degrees C. In surface water of the Weddell Sea (Southern Ocean) psychrophiles also dominated numerically in early autumn but the dominance declined obviously with the onset of winter-water and a decrease of chlorphyll a. Otherwise in surface water of the Southern Ocean CFUs were higher at 22 degrees C than at 1 degree C while activities were vice versa indicating at least a functional dominance of psychrophiles. Even in the temperate sediments of the German Bight true psychrophiles were present and a clear shift towards cold adapted communities in winter observed. Among the polar bacteria a more pronounced cold adaptation of Antarctic in comparison with Arctic isolates was obtained. The results and literature data indicate that stenothermic cold adapted bacteria play a significant role in the global marine environment. On the basis of the temperature response of our isolates from different habitats it is suggested to expand the definition of Morita in order to meet the cold adaptation strategies of the bacteria in the various cold habitats.

Bacteria↗

Seasonal virus removal by alternative onsite wastewater treatment systems.

Viral contamination of public waters is a leading health concern around the world, including in Minnesota where cold climate, abundant onsite systems on poor or thin soils, and abundant surface water resources present a significant risk of wastewater pathogens reaching sensitive water sources. Three alternative onsite treatment systems, a sand filter, peat filter and subsurface-flow constructed wetland (CW) at a field research site were evaluated for seasonal virus removal by seeding each with MS2 bacteriophage. The sand and peat filters and CW removed 2.7, 7.0, and 1.4 log10 of MS2, respectively, during summer and 1.8 and 6.9 log for the sand and peat filter during winter (CW not seeded). Somatic coliphage reductions for the sand filter, peat filter and CW were 2.9, 3.5, 1.0 log10 in summer, and 1.5, 2.8, 0.7 log10 during winter, respectively over a 3 year period. During this period, fecal coliform log10 reductions were 2.9, 4.6, 2.0 in summer for the sand and peat filters and CW, and 2.0, 4.6, 1.6 in winter. The peat filter was the most effective system for removing MS2, somatic coliphage and fecal coliforms during both winter and summer but all systems removed > 90% of viruses throughout the year.

Filtration↗

Nursing a patient with frostbite.

Frostbite is a condition that is associated with people living in countries with an extremely cold climate. However, it can affect people in the UK who are involved in winter sports, and is also associated with the homeless, people with a psychiatric illness, and those who misuse drugs and alcohol. Angela Davies describes the assessment and management of a patient with frostbite and identifies the challenges of managing these complex tissue injuries

Adult↗

Multiple sclerosis as first manifestation in oral and facial area: presentation of four cases.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system, whose etiology is unknown, and which is characteristic by the appearance of a diverse neurological symptomatology consisting of outbreaks or gradual deterioration and lesions in any location of the brain s white matter which may provoke the after-effect of a definitive demyelination of the area. The disease affects young people, with its appearance being most frequent between 20 and 40 years of age, in temperate and cold climates, and with a man-woman rate of 0.46/0.67. The magnitude of this disease lies in the fact that it is the primary cause for permanent disablement among young adults. We are presenting 4 cases of MS whose initial symptom of the disease was the appearance of paraesthesia in the maxillofacial area, affecting one or more ramifications of the trigeminal nerve, and a progression time varying from 15 days to one year. All the patients were clinically diagnosed, with their diagnostics being confirmed both with magnetic resonance imaging as well as through the study of their cerebrospinal fluid (CSF) and the evoked potentials (EPs). Manifestations in the oral and facial area were the first manifestation of the disease in all cases.

Adult↗

[Cold hardiness of Pinus ponderosa, P. banksian and P. tabulaeformis].

By the method of artificial freezing, this paper made a comparative study on the cold hardiness of Pinus ponderosa, P. banksiana and P. tabulaeformis, with their inherent mechanisms approached. The results showed that the cold hardiness of these three species was in the sequence of P. banksiana > P. tabulaeformis > P. ponderosa. P. banksiana had high bound water/free water ratio (7.0) and ABA content (164.3 microg x g(-1) FW) but low K+ (2450 microg x g(-1) DW) and soluble sugar (12.0%) , P. tabulaeformis had higher contents of ABA (95.8 microg x g(-1) FW), K+ (4538 microg x g(-1) DW) and soluble sugar (18.68%) but low bound water/free water ratio (2.58), while P. ponderosa had high soluble sugar content (18.05%) but low bound water/free water ratio (2.18) and K+ (2275 microg x g(-1) DW) and ABA (63.3 microg x g(-1) FW) contents. These differences might be the reasons resulting in the different cold hardiness of these three species. Low chlorophyll content and high carotenoid/chlorophyll ratio might also contribute to the cold hardiness of P. banksiana. Therefore, though the test species are all of cold hardiness, their inherent mechanisms may be different.

Adaptation, Physiological↗

[Seasonal changes in foliar micro-and ultra structure of two Sabina species and their relationships with cold tolerance].

In this paper, the foliar micro-and ultra structure of Sabina przewalskii and S. chinensis during growth and dormancy seasons was observed under microscope and transmission electron microscope, and the foliar soluble sugar content was measured, aimed to probe into their relationships with cold tolerance. The results showed that the foliar surface cells of these two Sabina species were covered with thick cuticular membrane, and the well-developed arenchyma appeared in the mesophyll. In growth season, starch grains accumulated in chloroplasts, but in dormancy season, the accumulated starch grains disappeared or diminished, while soluble sugar content had a larger increase. In wintertime, the chloroplasts of S. chinensis were injured, with some abnormal chloroplasts, increased plastoglobuli and some lipid drops, while those of S. przewalskii were not obviously injured. It was suggested that the cold tolerance of the two Sabina species was related to their well-developed arenchyma, accumulation of starch grains in growth season, and increase of soluble sugar content in dormancy season. S. przewalskii had more marked increase of soluble sugar content, and its chloroplasts were more stable than S. chinensis.

Adaptation, Physiological↗

Effects of steady hypothermia and normothermia on the electrocardiogram in human poikilothermia.

The electrocardiographic changes observed in (short-term) induced and accidental hypothermia are well known. We studied the electrocardiographic effects of steady mild hypothermia in 4 female patients with poikilothermia. 24h Holter recording revealed during mild hypothermia significantly decreased heart rate and prolongation of the QT interval in comparison with normothermia. During hypothermia the short-term heart rate variability and the circadian rhythm of heart rate variability were significantly higher than during normothermia. We conclude that in our patients even mild steady hypothermia induces electrocardiographic alterations. In patients with disorders of thermoregulation one should be on the alert for cardiovascular complications, especially in cold climates.

Adult↗

[Diseases of the cardiovascular system and the function of the endocrine glands in veterans of Soviet Antarctic expeditions].

The authors examined 58 men who had repeatedly participated in the Antarctic expeditions. In addition to a profound study of the cardiovascular system, the insulin tolerance test (0.1 U/kg simple insulin injected by intravenous drip for 90 minutes) was made, permitting the degree of tissue insulin resistance to be quantitatively estimated with measurements of the content of cyclic nucleotides in blood leukocytes and of immunoreactive insulin, C-peptide and counterinsular hormones in the blood before and after the functional test. It was established that with the increase of the number of Antarctic winterings tissue insulin resistance naturally grows regardless of the age of the examinees, manifesting itself in an increase of basal insulinemia, the content of cyclic adenosine monophosphate in blood leukocytes, appreciable increment of insulinemia after infusion of exogenous insulin. Analogous changes were detected in polar researchers suffering from coronary disease, essential hypertension irrespective of the number of winterings. It is concluded that the rise of tissue insulin resistance occurring under the influence of multiple exposures to natural and social factors of high latitudes is a predisposing factor of the formation of cardiovascular pathology.

Adaptation, Physiological↗

Poikilothermia in a 68-year-old female. A risk factor for accidental hypothermia, or hyperthermia.

A 68-year-old woman presented in wintertime in a cold climate with ataxia and numbness in her legs and was found to be profoundly hypothermic in hospital. No endocrine or neurological cause for hypothermia could be distinguished. Physiological investigation, including a sympathetic release test, exposure to gradually increasing environmental temperatures and prolonged exposure to a high temperature suggested she was at that time regulating her core temperature around a set value which was several degrees lower than normal. Metabolic rate was 42 per cent below the value predicted from standard tables. Further measurements over a one-month period in a warm climate suggested a poikilothermic temperature control mechanism, with a possible risk of environmental hyperthermia. No pathological basis for this disorder has yet been identified, but it is suggested that a small localized hypothalamic vascular event has occurred.

Aged↗