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881.
Japani R?nnemaa Jukka Marniemi Aila Leino Hannu Karanko Pauli Puukka Veikko A. Koivisto 《European journal of applied physiology and occupational physiology》1991,62(2):109-115
Both exercise and high ambient temperatures stimulate the secretion of counterregulatory hormones which can change glucose homeostasis. We studied whether in diabetic patients there are any differences in the hormonal response to exercise performed at cool or warm ambient temperatures. A study was performed on eight male insulin-dependent patients at rest and during exercise at +10 degrees C and +30 degrees C. Exercise consisted of three consecutive 15-min periods at 60% of maximal aerobic capacity. The concentrations of plasma lactate and counterregulatory hormones at rest were similar at warm and cool temperature, whereas prolactin concentration was higher (P less than 0.01) at +30 degrees C. Exercise resulted in an increase in noradrenaline, growth hormone and prolactin (P less than 0.01), prevented the diurnal decrease in cortisol, but had no effect on glucagon. Hormone responses to exercise were similar at +10 degrees C and at +30 degrees C, except for cortisol and noradrenaline which showed greater responses at warm than at cool temperatures. This may have been due to the higher relative work load at warm compared to cool temperatures as suggested by the higher heart rate and greater increase of lactate at +30 degrees C. These data indicate that within a range of ambient temperatures commonly occurring in sports, the response of counterregulatory hormones is largely independent of ambient temperature in insulin-dependent diabetic patients. 相似文献
882.
Development and fate of Eutreptiella gymnastica bloom in nutrient-enriched enclosures in the coastal Baltic Sea 总被引:1,自引:0,他引:1
Response of the phytoplankton community to bottom-up (nutrients,organic carbon source) and top-down (fish) manipulations, bothsingly and together, were studied daily during a 3 week periodin July 1993 by using eight 50 m3 mesocosms in the coastal northernBaltic Sea. Nutrient additions (once per week) invoked a seriesof blooms of Eutreptiella gymnastica Throndsen (Euglenophyceae)(up to 13 x 103 cells ml1) which formed the major part(6090%) of the total autotrophic biomass. After rapiddepletion of nutrients (23 days) from the surface layer(06 m) downwards migration and a subsequent peak of E.gymnasticain the lower part of the water columns (612 m) followed.Settled material collected from the bottom of the enclosurescontained a considerable amount of E.gymnastica cells and restingcysts. Nevertheless, sinking loss rates of E.gymnastica wereestimated to be less than 1% day1 of the suspended cellnumbers. The fate of E.gymnastica blooms was estimated to begrazing through mesozooplankton. However, provided the nutrientsare plentiful in the water column, the growth potential of E.gymnasticaappears to exceed the ambient grazing pressure. If the nutrientsbecome depleted, it seems to be effectively controlled by mesozooplanktongrazing, which is probably limiting the likelihood of massiveE.gymnastica blooms in the coastal Baltic Sea. Our study suggeststhat E.gymnastica appears to be a fast-growing fugitive (bloom)species with flexible behavioural (vertical migration) and lifehistory (cyst formation) adaptations which is able to exertdominant role and direct trophic relations similar to otherbloom species adapted for decaying turbulence and high nutrientenvironments. 相似文献
883.
Jukka Bisi Sami Kurki Marko Svensberg Tuija Liukkonen 《European Journal of Wildlife Research》2007,53(4):304-314
The growth of the Finnish wolf (Canis lupus) population during the last years has highlighted people’s contradictory attitudes toward wolves. The supranational conservation
objectives brought on by Finland’s membership in the European Union (EU) and the regional application of the official policy
on wolves have led to conflicts. This article is based on the preparation process of the wolf management plan in Finland.
As a part of the process, a nationwide hearing was arranged in 2004. Fear of wolves is widespread and even more common in
areas with low wolf population. People living in areas where wolves occur feel that they can no longer influence decision
making which affects them and that the authorities, conservationists, and the EU do not listen to their opinions. Numerous
requests have been made for the legislation and its interpretation, and concessions to these requests would promote consensus
and increase tolerance for wolves. Proposed changes include reforming the damage compensation system and formulating a clearer
interpretation of the conservation status of wolves. However, it seems impossible to create a policy that would be universally
supported. As the wolf question has become more central in environmental policy, the conservation and management of the species
have become more complicated, and the cooperation between various interest groups has declined. The wolf conflict could be
mitigated by compromises, but because the conflict is value-based, solutions are illusive. 相似文献
884.
Doug M. Boyer Alistair R. Evans Jukka Jernvall 《American journal of physical anthropology》2010,142(2):194-210
Plesiadapis cookei is an extinct relative of extant euarchontans (primates, dermopterans; scandentians), which lived in North America during the late Paleocene. P. cookei body mass has been estimated to be ~2.2 kg, making it large compared with other species of its genus from North America, but similar to some from Europe. In particular, size as well as dental form similarities to P. russelli have been noted. However, it is thought that P. russelli evolved from P. tricuspidens, and into Platychoerops daubrei. Dental similarities among P. cookei, P. russelli, and P. daubrei have been hypothesized to reflect a more folivorous diet than utilized by P. tricuspidens. Here we test the hypothesis that P. cookei is more dietarily specialized than P. tricuspidens by quantifying functionally significant aspects of molar, premolar, and incisor forms. Casts of M2s and P4s of P. tricuspidens, P. cookei, and P. daubrei were microCT‐scanned. We measured the relief index and/or the complexity from surface reconstructions of scans. Results show that P. cookei has higher M2 relief and complexity than P. tricuspidens; P. daubrei exhibits the highest relief and complexity. Similarly, P. cookei has a more complex P4 than P. tricuspidens, whereas that of P. daubrei exhibits the highest complexity. Finally, the I1 of P. cookei resembles more the incisor of P. daubrei than that of P. tricuspidens. Because high relief and complexity of dentitions are related to fibrous plant diets in living mammals, these findings support the hypothesis that previously identified similarities among P. cookei, P. russelli and P. daubrei reflect a folivorous diet. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
885.
We studied the matrilinear genetic structure of the Siberian tit Parus cinctus by sequencing 911 bp of the mitochondrial control region of 56 birds from Fennoscandia and 3 from Yakutia, central Siberia, representing subspecies P. c. lapponicus and P. c. cinctus , respectively. One major haplotype comprised 35.7% of all birds and was present in all Fennoscandian populations. Sequence variation of 5 museum specimens from Norway fitted with the pattern of the present-day birds. The nucleotide diversity was 0.00205±0.00025 in the Fennoscandian population and no population structuring was detected. The star-like phylogeny suggests a recent expansion of the population size in the evolutionary time scale. A modern decline of the population size from 200 000 pairs to 50 000 pairs in Finland has resulted from cutting and fragmentation of old-growth forests, but the effects of this could not yet be detected in the mtDNA pattern. However, the nucleotide diversity differed among populations being the highest at Kuusamo, close to the Russian border. Conceivably, the gene flow maintained by the substantial migration of Siberian tits is sufficient to prevent differentiation of local populations in Fennoscandia. Presumably the large conservation areas in NE Finland and on the Russian side of the border contribute to the high genetic variation observed in the Kuusamo population. Comparison of the mtDNA phylogeny of the Siberian tit with the phylogenies of the great tit, the blue tit and the willow tit showed that the Siberian tit and some other non-migratory species of the foliage gleaning guild share similar post glacial histories in the western palaearctic. 相似文献
886.
887.
888.
Jean P. Elbers Mark F. Rogers Polina L. Perelman Anastasia A. Proskuryakova Natalia A. Serdyukova Warren E. Johnson Petr Horin Jukka Corander David Murphy Pamela A. Burger 《Molecular ecology resources》2019,19(4):1015-1026
Researchers have assembled thousands of eukaryotic genomes using Illumina reads, but traditional mate‐pair libraries cannot span all repetitive elements, resulting in highly fragmented assemblies. However, both chromosome conformation capture techniques, such as Hi‐C and Dovetail Genomics Chicago libraries and long‐read sequencing, such as Pacific Biosciences and Oxford Nanopore, help span and resolve repetitive regions and therefore improve genome assemblies. One important livestock species of arid regions that does not have a high‐quality contiguous reference genome is the dromedary (Camelus dromedarius). Draft genomes exist but are highly fragmented, and a high‐quality reference genome is needed to understand adaptation to desert environments and artificial selection during domestication. Dromedaries are among the last livestock species to have been domesticated, and together with wild and domestic Bactrian camels, they are the only representatives of the Camelini tribe, which highlights their evolutionary significance. Here we describe our efforts to improve the North African dromedary genome. We used Chicago and Hi‐C sequencing libraries from Dovetail Genomics to resolve the order of previously assembled contigs, producing almost chromosome‐level scaffolds. Remaining gaps were filled with Pacific Biosciences long reads, and then scaffolds were comparatively mapped to chromosomes. Long reads added 99.32 Mbp to the total length of the new assembly. Dovetail Chicago and Hi‐C libraries increased the longest scaffold over 12‐fold, from 9.71 Mbp to 124.99 Mbp and the scaffold N50 over 50‐fold, from 1.48 Mbp to 75.02 Mbp. We demonstrate that Illumina de novo assemblies can be substantially upgraded by combining chromosome conformation capture and long‐read sequencing. 相似文献
889.
Elina Numminen Claire Chewapreecha Jukka Sirén Claudia Turner Paul Turner Stephen D. Bentley Jukka Corander 《Proceedings. Biological sciences / The Royal Society》2014,281(1794)
There has been growing interest in the statistics community to develop methods for inferring transmission pathways of infectious pathogens from molecular sequence data. For many datasets, the computational challenge lies in the huge dimension of the missing data. Here, we introduce an importance sampling scheme in which the transmission trees and phylogenies of pathogens are both sampled from reasonable importance distributions, alleviating the inference. Using this approach, arbitrary models of transmission could be considered, contrary to many earlier proposed methods. We illustrate the scheme by analysing transmissions of Streptococcus pneumoniae from household to household within a refugee camp, using data in which only a fraction of hosts is observed, but which is still rich enough to unravel the within-household transmission dynamics and pairs of households between whom transmission is plausible. We observe that while probability of direct transmission is low even for the most prominent cases of transmission, still those pairs of households are geographically much closer to each other than expected under random proximity. 相似文献
890.
Breeding habitat choice and investment decisions are key contributors to fitness in animals. Density of individuals is a well-known cue of habitat quality 相似文献