936 resultados para Cold-adaptivity


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In Finland, suckler cow production is carried out in circumstances characterized by a long winter period and a short grazing period. The traditional winter housing system for suckler cows has been insulated or uninsulated buildings, but there is a demand for developing less expensive housing systems. In addition, more information is needed on new winter feeding strategies, carried out in inexpensive winter facilities with conventional (hay, grass silage, straw) or alternative (treated straw, industrial by-product, whole-crop silage) feeds. The new feeding techniques should not have any detrimental effects on animal welfare in order to be acceptable to both farmers and consumers. Furthermore, no official feeding recommendations for suckler cows are available in Finland and, thus, recommendations for dairy cows have been used. However, this may lead to over- or underfeeding of suckler cows and, finally, to decreased economic output. In Experiment I, second-calf beef-dairy suckler cows were used to compare the effects of diets based on hay (H) or urea-treated straw (US) at two feeding levels (Moderate; M vs. Low; L) on the performance of cows and calves. Live weight (LW) gain during the indoor feeding was lower for cows on level L than on level M. Cows on diet US lost more LW indoors than those on diet H. The cows replenished the LW losses on good pasture. Calf LW gain and cow milk production were unaffected by the treatments. Conception rate was unaffected by the treatments but was only 69%. Urea-treated straw proved to be a suitable winter feed for spring-calving suckler cows. Experiment II studied the effects of feeding accuracy on the performance of first- and second-calf beef-dairy cows and calves. In II-1, the day-to-day variation in the roughage offered ranged up to ± 40%. In II-2, the same variation was used in two-week periods. Variation of the roughages offered had minor effects on cow performance. Reproduction was unaffected by the feeding accuracy. Accurate feeding is not necessary for young beef-dairy crosses, if the total amount of energy offered over a period of a few weeks fulfills the energy requirements. Effects of feeding strategies with alternative feeds on the performance of mature beef-dairy and beef cows and calves were evaluated in Experiment III. Two studies consisted of two feeding strategies (Step-up vs. Flat-rate) and two diets (Control vs. Alternative). There were no differences between treatments in the cow LW, body condition score (BCS), calf pre-weaning LW gain and cow reproduction. A flat-rate strategy can be practised in the nutrition of mature suckler cows. Oat hull based flour-mill by product can partly replace grass silage and straw in the winter diet. Whole-crop barley silage can be offered as a sole feed to suckler cows. Experiment IV evaluated during the winter feeding period the effects of replacing grass silage with whole-crop barley or oat silage on mature beef cow and calf performance. Both whole-crop silages were suitable winter feeds for suckler cows in cold outdoor winter conditions. Experiment V aimed at assessing the effects of daily feeding vs. feeding every third day on the performance of mature beef cows and calves. No differences between the treatments were observed in cow LW, BCS, milk production and calf LW. The serum concentrations of urea and long-chain fatty acids were increased on the third day after feeding in the cows fed every third day. Despite of that the feeding every third day is an acceptable feeding strategy for mature suckler cows. Experiment VI studied the effects of feeding levels and long-term cold climatic conditions on mature beef cows and calves. The cows were overwintered in outdoor facilities or in an uninsulated indoor facility. Whole-crop barley silage was offered either ad libitum or restricted. All the facilities offered adequate shelter for the cows. The restricted offering of whole-crop barley silage provided enough energy for the cows. The Finnish energy recommendations for dairy cows were too high for mature beef breed suckler cows in good body condition at housing, even in cold conditions. Therefore, there is need to determine feeding recommendations for suckler cows in Finland. The results showed that the required amount of energy can be offered to the cows using conventional or alternative feeds provided at a lower feeding level, with an inaccurate feeding, flat-rate feeding or feeding every third day strategy. The cows must have an opportunity to replenish the LW and BCS losses at pasture before the next winter. Production in cold conditions can be practised in inexpensive facilities when shelter against rain and wind, a dry resting place, adequate amounts of feed suitable for cold conditions and water are provided for the animals as was done in the present study.

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Delayed-onset muscle soreness, or ‘DOMS’, affects many people after exercise and can impair future performance. It usually peaks one to four days after exercise and several strategies are used to overcome it. The effectiveness and safety of many of these strategies applied and promoted is unknown.

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- Introduction Heat-based training (HT) is becoming increasingly popular as a means of inducing acclimation before athletic competition in hot conditions and/or to augment the training impulse beyond that achieved in thermo-neutral conditions. Importantly, current understanding of the effects of HT on regenerative processes such as sleep and the interactions with common recovery interventions remain unknown. This study aimed to examine sleep characteristics during five consecutive days of training in the heat with the inclusion of cold-water immersion (CWI) compared to baseline sleep patterns. - Methods Thirty recreationally-trained males completed HT in 32 ± 1 °C and 60% rh for five consecutive days. Conditions included: 1) 90 min cycling at 40 % power at VO2max (Pmax) (90CONT; n = 10); 90 min cycling at 40 % Pmax with a 20 min CWI (14 ± 1 °C; 90CWI; n = 10); and 30 min cycling alternating between 40 and 70 % Pmax every 3 min, with no recovery intervention (30HIT; n = 10). Sleep quality and quantity was assessed during HT and four nights of 'baseline' sleep (BASE). Actigraphy provided measures of time in and out of bed, sleep latency, efficiency, total time in bed and total time asleep, wake after sleep onset, number of awakenings, and wakening duration. Subjective ratings of sleep were also recorded using a 1-5 Likert scale. Repeated measures analysis of variance (ANOVA) was completed to determine effect of time and condition on sleep quality and quantity. Cohen's d effect sizes were also applied to determine magnitude and trends in the data. - Results Sleep latency, efficiency, total time in bed and number of awakenings were not significantly different between BASE and HT (P > 0.05). However, total time asleep was significantly reduced (P = 0.01; d = 1.46) and the duration periods of wakefulness after sleep onset was significantly greater during HT compared with BASE (P = 0.001; d = 1.14). Comparison between training groups showed latency was significantly higher for the 30HIT group compared to 90CONT (P = 0.02; d = 1.33). Nevertheless, there were no differences between training groups for sleep efficiency, total time in bed or asleep, wake after sleep onset, number of awakenings or awake duration (P > 0.05). Further, cold-water immersion recovery had no significant effect on sleep characteristics (P > 0.05). - Discussion Sleep plays an important role in athletic recovery and has previously been demonstrated to be influenced by both exercise training and thermal strain. Present data highlight the effect of HT on reduced sleep quality, specifically reducing total time asleep due to longer duration awake during awakenings after sleep onset. Importantly, although cold water recovery accelerates the removal of thermal load, this intervention did not blunt the negative effects of HT on sleep characteristics. - Conclusion Training in hot conditions may reduce both sleep quantity and quality and should be taken into consideration when administering this training intervention in the field.

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From the Soviet point of view the actual substance of Soviet-Finnish relations in the second half of 1950s clearly differed from the contemporary and later public image, based on friendship and confidence rhetoric. As the polarization between the right and the left became more underlined in Finland in the latter half of the 1950s, the criticism towards the Soviet Union became stronger, and the USSR feared that this development would have influence on Finnish foreign policy. From the Soviet point of view, the security commitments of FCMA-treaty needed additional guarantees through control of Finnish domestic politics and economic relations, especially during international crises. In relation to Scandinavia, Finland was, from the Soviet point of view, the model country of friendship or neutrality policy. The influence of the Second Berlin Crisis or the Soviet-Finnish Night Frost Crisis in 1958-1959 to Soviet policy towards Scandinavia needs to be observed from this point of view. The Soviet Union used Finland as a tool, in agreement with Finnish highest political leadership, for weakening of the NATO membership of Norway and Denmark, and for maintaining Swedish non-alliance. The Finnish interest to EFTA membership in the summer of 1959, at the same time with the Scandinavian countries, seems to have caused a panic reaction in the USSR, as the Soviets feared that these economic arrangements would reverse the political advantages the country had received in Finland after the Night Frost Crisis. Together with history of events, this study observes the interaction of practical interests and ideologies, both in individuals and in decision-making organizations. The necessary social and ideological reforms in the Soviet Union after 1956 had influence both on the legitimacy of the regime, and led to contradictions in the argumentation of Soviet foreign policy. This was observed both in the own camp as well as in the West. Also, in Finland a breakthrough took place in the late 1950's: as the so-called counter reaction lost to the K-line, "a special relationship" developed with the Soviet Union. As a consequence of the Night Frost Crisis the Soviet relationship became a factor decisively defining the limits of domestic politics in Finland, a part of Finnish domestic political argumentation. Understood from this basis, finlandization is not, even from the viewpoint of international relations, a special case, but a domestic political culture formed by the relationship between a dominant state, a superpower, and a subordinate state, Finland.

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National identity signifies and makes state s defence- and foreign policy behaviour meaningful. National consciousness is narrated into existence by narratives upon one s own exceptionalism and Otherness of the other nations. While national identity may be understood merely as a self-image of a nation, defence identity refers to the borders of Otherness and issues that have been considered as worth defending for. As national identities and all the world order models are human constructions, they may be changed by the human efforts as well; states and nations may deliberately promote communitarian or even cosmopolitan equality and tolerance without borders of Otherness. The main research question of the thesis is: How does Poland constitute herself as a nation and a state agent in the current world order and to what extent have contextual foreign and defence policy interactions changed the Polish defence identity during the post-Cold War era? The main empirical argument of the thesis is: Poland is a narrated idea of a Christian Catholic nation-state, which the Polish State, the Catholic Church of Poland, the Armed Forces of Poland as well as a majority of the Polish nation share. Polish defence identity has been almost impenetrable to contextual foreign and defence policy interactions during the post-Cold War era. While Christian religious ontology binds corporate Poland together, allowing her to survive any number of military and political catastrophes, it simultaneously brings her closer to the USA, raises tensions in the infidel EU-context, and restrains corporate Poland s pursuit of communitarian, or even cosmopolitan, global equality and tolerance. It is not the case that corporate Poland s foreign and defence policy orientation is instinctively Atlanticist by nature, as has been argued. Rather, it has been the State s rational project to overcome a habituated and reified fear of becoming geopolitically sandwiched between Russian and German Others by leaning on the USA; among the Polish nation, support for the USA has been declining since 2004. It is not corporate Poland either that has turned into a constructive European , as has been argued, but rather the Polish nation that has, at least partly, managed to emancipate itself from its habituation to a betrayal by Europe narrative, since it favours the EU as much as it favours NATO. It seems that in the Polish case a truly common European CFSP vis-à-vis Russia may offer a solution that will emancipate the Polish State from its habituated EU-sceptic role identity and corporate Poland from its narrated borders of Otherness towards Russia and Germany, but even then one cannot be sure whether any other perspective than the Polish one on a common stand towards Russia would satisfy the Poles themselves.

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The activity of hepatic tryptophan pyrrolase in rats exposed to cold increased rapidly and reached a maximum of three-fold at 8 h. On continued exposure up to 48 h stress, the activity partly decreased but remained at a level higher than the initial. Withdrawal from the cold stress reversed the change. Adrenalectomy or treatment with inhibitors of protein synthesis abolished the increase in the enzyme activity during cold stress indicating a possible involvement of corticosteroids and de novo protein synthesis. Treatment with drugs known to block autonomic nervous system failed to inhibit the cold-mediated increase in enzyme activity. The results suggest that the increase in enzyme activity obtained on cold exposure is mediated by corticosteroids and not by either indoleaklylamines or autonomic nervous system. The changes in the enzyme obtained under cold stress with respect to the overshoot phenomenon, relationship to the degree of stress and reversibility on withdrawal from the stress indicate the "adaptate" nature of the response.

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Increased anthropogenic loading of nitrogen (N) and phosphorus (P) has led to an eutrophication problem in the Baltic Sea, and the spring bloom is a key component in the biological uptake of increased nutrient concentrations. The spring bloom in the Baltic Sea is dominated by both diatoms and dinoflagellates. However, the sedimentation of these groups is different: diatoms tend to sink to the sea floor at the end of the bloom, while dinoflagellates to a large degree are been remineralized in the euphotic zone. Understanding phytoplankton competition and species specific ecological strategies is thus of importance for assessing indirect effects of phytoplankton community composition on eutrophication problems. The main objective of this thesis was to describe some basic physiological and ecological characteristics of the main cold-water diatoms and dinoflagellates in the Baltic Sea. This was achieved by specific studies of: (1) seasonal vertical positioning, (2) dinoflagellate life cycle, (3) mixotrophy, (4) primary production, respiration and growth and (5) diatom silicate uptake, using cultures of common cold-water diatoms: Chaetoceros wighamii, C. gracilis, Pauliella taeniata, Thalassiosira baltica, T. levanderi, Melosira arctica, Diatoma tenuis, Nitzschia frigida, and dinoflagellates: Peridiniella catenata, Woloszynskia halophila and Scrippsiella hangoei. The diatoms had higher primary production capacity and lower respiration rate compared with the dinoflagellates. This difference was reflected in the maximum growth rate, which for the examined diatoms range from 0.6 to 1.2 divisions d-1, compared with 0.2 to 0.3 divisions d-1 for the dinoflagellates. Among diatoms there were species specific differences in light utilization and uptake of silicate, and C. wighamii had the highest carbon assimilation capacity and maximum silicate uptake. The physiological properties of diatoms and dinoflagellates were used in a model of the onset of the spring bloom: for the diatoms the model could predict the initiation of the spring bloom; S. hangoei, on the other hand, could not compete successfully and did not obtain positive growth in the model. The other dinoflagellates did not have higher growth rates or carbon assimilation rates and would thus probably not perform better than S. hangoei in the model. The dinoflagellates do, however, have competitive advantages that were not included in the model: motility and mixotrophy. Previous investigations has revealed that the chain-forming P. catenata performs diurnal vertical migration (DVM), and the results presented here suggest that active positioning in the water column, in addition to DVM, is a key element in this species' life strategy. There was indication of mixotrophy in S. hangoei, as it produced and excreted the enzyme leucine aminopeptidase (LAP). Moreover, there was indirect evidence that W. halophila obtains carbon from other sources than photosynthesis when comparing increase in cell numbers with in situ carbon assimilation rates. The results indicate that mixotrophy is a part of the strategy of vernal dinoflagellates in the Baltic Sea. There were also indications that the seeding of the spring bloom is very important for the dinoflagellates to succeed. In mesocosm experiments dinoflagellates could not compete with diatoms when their initial numbers were low. In conclusion, this thesis has provided new information about the basic physiological and ecological properties of the main cold-water phytoplankton in the Baltic Sea. The main phytoplankton groups, diatoms and dinoflagellates, have different physiological properties, which clearly separate their life strategies. The information presented here could serve as further steps towards better prognostic models of the effects of eutrophication in the Baltic Sea.

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The mid-December 2006 to late January 2007 flood in southern Peninsular Malaysia was the worst flood in a century and was caused by three extreme precipitation episodes. These extreme precipitation events were mainly associated with strong northeasterly winds over the South China Sea. In all cases, the northeasterlies penetrated anomalously far south and followed almost a straight trajectory. The elevated terrain over Sumatra and southern Peninsular Malaysia caused low-level convergence. The strong easterly winds near Java associated with the Rossby wave-type response to Madden-Julian Oscillation (MJO) inhibited the counter-clockwise turning of the northeasterlies and the formation of the Borneo vortex, which, in turn, enhanced the low-level convergence over the region. The abrupt termination of the Indian Ocean Dipole (IOD) in December 2006 played a secondary role as warmer equatorial Indian Ocean helped in the MJO formation.

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This is a study of ultra-cold Fermi gases in different systems. This thesis is focused on exotic superfluid states, for an example on the three component Fermi gas and the FFLO phase in optical lattices. In the two-components case, superfluidity is studied mainly in the case of the spin population imbalanced Fermi gases and the phase diagrams are calculated from the mean-field theory. Different methods to detect different phases in optical lattices are suggested. In the three-component case, we studied also the uniform gas and harmonically trapped system. In this case, the BCS theory is generalized to three-component gases. It is also discussed how to achieve the conditions to get an SU(3)-symmetric Hamiltonian in optical lattices. The thesis is divided in chapters as follows: Chapter 1 is an introduction to the field of cold quantum gases. In chapter 2 optical lattices and their experimental characteristics are discussed. Chapter 3 deals with two-components Fermi gases in optical lattices and the paired states in lattices. In chapter 4 three-component Fermi gases with and without a harmonic trap are explored, and the pairing mechanisms are studied. In this chapter, we also discuss three-component Fermi gases in optical lattices. Chapter 5 devoted to the higher order correlations, and what they can tell about the paired states. Chapter 6 concludes the thesis.

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1. Accumulation of ubiquinone in the livers of rats exposed to a cold environment was shown to be due to both decreased catabolism during the entire experimental period and increased synthesis during an intermediate stage (10–20 days). 2. The increased endogenous synthesis in the cold-exposed rats was eliminated when ubiquinone accumulated in the liver after exposure for 40 days (coinciding with cclimatization), or by absorption of the exogenous dietary supply, possibly by the mechanism of end-product regulation.

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The Cold War era was characterized by ideological struggles that had a major impact on economic decision-making, and also on management practice. To date, however, these ideological struggles have received little attention from management and organizational scholars. To partially fill this research gap, we focus on the role of the media in these ideological struggles. Our starting point is that the media both reflect more general societal debates but also act as an agency promoting specific kinds of ideas and ideologies. In this sense, the media exercise significant power in society; this influece, however, is often subtle and easily dismissed in historical analyses focusing on political and corporate decision-making. In this article, we focus on the role of business journalism in the ideological struggles of the Cold War era. Our case in point is Finland, which is arguably a particularly interesting example due to its geo-political position between East and West. Our approach is socio-historical: we focus on the emergence and development of business journalism in the context of the specific struggles in the Finnish political and economic fields. Our analysis shows how the business journalists struggled between nationalist, pro-Soviet and pro-West political forces, but gradually developed into an increasingly influential force promoting neo-liberal ideology.