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71.
Grete Helen Meisfjord Jørgensen Silje Hanche-Olsen Liestøl Knut Egil Bøe 《Applied animal behaviour science》2011,129(2-4):100-110
The aim of this study was to investigate the use of items intended to provide enrichment during turnout, both for individual and group kept horses in an attempt to reduce the amount of passive behaviours. The study was divided into two parts, where study 1 involved eight horses rotated through eight individual paddocks, each containing one of seven enrichment items and one paddock being kept without item, functioning as a control. The horses’ item-directed behaviours; passive behaviours or other non-item related activities were scored using instantaneous sampling, every minute for 1 h at the beginning and the end of the turnout period. Study 2 involved six horse groups (3–6 horses) and the same scoring methods and ethogram as in study 1. The four items that the horses interacted the most with during study 1 (straw STRA, ball filled with concentrates CBALL, branches BRAN and scratching pole POLE) are investigated in study 2. In addition, the amount of social interactions was recorded.Both horses kept individually (P < 0.05) and in groups (P < 0.0001) performed significantly more item-directed behaviours towards edible items like STRA and CBALL than other objects. There was, however, no overall relation between the numbers of item-directed behaviours and the number of passive behaviours observed, indicating that the enrichment items did not alone reduce the amount of passive behaviours during turnout periods. Such a reduction was, however, only apparent when horses spent more time eating green leaves growing on the paddock surface (R = ?0.97 study 1, R = ?0.67 study 2, P < 0.0001). Access to STRA in group kept horses also seemed to reduce the amount of agonistic behaviours (P < 0.0001). In conclusion, if grass is not available in paddocks, the provision of roughage reduces the amount of passive behaviours in singly kept horses and it also reduces the risk of agonistic interactions between horses kept in group. 相似文献
72.
ABSTRACT: BACKGROUND: Geographical isolation has generated a distinct difference between Atlantic salmon of European and North American Atlantic origin. The European Atlantic salmon generally has 29 pairs of chromosomes and 74 chromosome arms whereas it has been reported that the North American Atlantic salmon has 27 chromosome pairs and an NF of 72. In order to predict the major chromosomal rearrangements causing these differences, we constructed a dense linkage map for Atlantic salmon of North American origin and compared it with the well-developed map for European Atlantic salmon. RESULTS: The presented male and female genetic maps for the North American subspecies of Atlantic salmon, contains 3,662 SNPs located on 27 linkage groups. The total lengths of the female and male linkage maps were 2,153 cM and 968 cM respectively, with males characteristically showing recombination only at the telomeres. We compared these maps with recently published SNP maps from European Atlantic salmon, and predicted three chromosomal reorganization events that we then tested using fluorescence in situ hybridization (FISH) analysis. The proposed rearrangements, which define the differences in the karyotypes of the North American Atlantic salmon relative to the European Atlantic salmon, include the translocation of the p arm of ssa01 to ssa23 and polymorphic fusions: ssa26 with ssa28, and ssa08 with ssa29. CONCLUSIONS: This study identified major chromosomal differences between European and North American Atlantic salmon. However, while gross structural differences were significant, the order of genetic markers at the fine-resolution scale was remarkably conserved. This is a good indication that information from the International Cooperation to Sequence the Atlantic salmon Genome, which is sequencing a European Atlantic salmon, can be transferred to Atlantic salmon from North America. 相似文献
73.
Emily R. A. Cramer Even Stensrud Gunnhild Marthinsen Silje Hogner Lars Erik Johannessen Terje Laskemoen Marie‐Christine Eybert Tore Slagsvold Jan T. Lifjeld Arild Johnsen 《Ecology and evolution》2016,6(5):1363-1377
Divergent sexual selection within allopatric populations may result in divergent sexual phenotypes, which can act as reproductive barriers between populations upon secondary contact. This hypothesis has been most tested on traits involved in precopulatory sexual selection, with less work focusing on traits that act after copulation and before fertilization (i.e., postcopulatory prezygotic traits), particularly in internally fertilizing vertebrates. However, postcopulatory sexual selection within species can also drive trait divergence, resulting in reduced performance of heterospecific sperm within the female reproductive tract. Such incompatibilities, arising as a by‐product of divergent postcopulatory sexual selection in allopatry, can represent reproductive barriers, analogous to species‐assortative mating preferences. Here, we tested for postcopulatory prezygotic reproductive barriers between three pairs of taxa with diverged sperm phenotypes and moderate‐to‐high opportunity for postcopulatory sexual selection (barn swallows Hirundo rustica versus sand martins Riparia riparia, two subspecies of bluethroats, Luscinia svecica svecica versus L. s. namnetum, and great tits Parus major versus blue tits Cyanistes caeruleus). We tested sperm swimming performance in fluid from the outer reproductive tract of females, because the greatest reduction in sperm number in birds occurs as sperm swim across the vagina. Contrary to our expectations, sperm swam equally well in fluid from conspecific and heterospecific females, suggesting that postcopulatory prezygotic barriers do not act between these taxon pairs, at this stage between copulation and fertilization. We therefore suggest that divergence in sperm phenotypes in allopatry is insufficient to cause widespread postcopulatory prezygotic barriers in the form of impaired sperm swimming performance in passerine birds. 相似文献
74.
Silje Z. Krokeide Nils Bolstad Jon K. Laerdahl Magnar Bjrs Luisa Luna 《Protein expression and purification》2009,65(2):160-164
The base excision repair (BER) pathway is mainly responsible for the repair of a vast number of non-bulky lesions produced by alkylation, oxidation or deamination of bases. DNA glycosylases are the key enzymes that recognize damaged bases and initiate BER by catalyzing the cleavage of the N-glycosylic bond between the base and the sugar. Many of the mammalian DNA glycosylases have been identified by a combination of biochemical and bioinformatics analysis. Thus, a mammalian family of three proteins (NEIL1, NEIL2 and NEIL3) that showed homology to the Escherichia coli Fpg/Nei DNA glycosylases was identified. Two of the proteins, NEIL1 and NEIL2 have been thoroughly characterized and shown to initiate BER of a diverse number of oxidized lesions. However, much less is known about NEIL3. The biochemical properties of NEIL3 have not been elucidated. This is mainly due to the difficulty in the expression and purification of NEIL3. Here, we describe the expression and partial purification of full-length human NEIL3 and the expression, purification and characterization of a truncated human core-NEIL3 (amino acids 1–301) that contains the complete E. coli Fpg/Nei-like domain but lacks the C-terminal region. 相似文献
75.
Sveinung Wergeland S?rbye Silje Fismen Tore Jarl Gutteberg Elin Synn?ve Mortensen Finn Egil Skjeldestad 《PloS one》2014,9(11)
Background
In Norway, repeat cytology and HPV testing comprise delayed triage of women with minor cytological lesions. The objective of this study was to evaluate HPV DNA and HPV mRNA testing in triage of women with an ASC-US/LSIL diagnosis.Materials and Methods
We used repeat cytology, HPV DNA testing (Cobas 4800) and HPV mRNA testing (PreTect HPV-Proofer) to follow up 311 women aged 25–69 years with ASC-US/LSIL index cytology.Results
Of 311 women scheduled for secondary screening, 30 women (9.6%) had ASC-H/HSIL cytology at triage and 281 women (90.4%) had ASC-US/LSIL or normal cytology. The HPV DNA test was positive in 92 (32.7%) of 281 instances, and 37 (13.2%) were mRNA positive. Of the 132 women with repeated ASC-US/LSIL, we received biopsies from 97.0% (65/67) of the DNA-positive and 92.9% (26/28) of the mRNA-positive cases. The positive predictive values for CIN2+ were 21.5% (14/65) for DNA positive and 34.6% (9/26) for mRNA positive (ns). The odds ratio for being referred to colposcopy in DNA-positive cases were 2.8 times (95% CI: 1.8–4.6) higher that of mRNA-positive cases. Compared to the mRNA test, the DNA test detected four more cases of CIN2 and one case of CIN3.Conclusions
The higher positivity rate of the DNA test in triage leads to higher referral rate for colposcopy and biopsy, and subsequent additional follow-up of negative biopsies. By following mRNA-negative women who had ASC-US/LSIL at triage with cytology, the additional cases of CIN2+ gained in DNA screening can be discovered. Our study indicates that in triage of repeated ASC-US/LSIL, HPV mRNA testing is more specific and is more relevant in clinical use than an HPV DNA test. 相似文献76.
Xinxin Wang Ole Jacob Broch Silje Forbord Aleksander Handå Jorunn Skjermo Kjell Inge Reitan Olav Vadstein Yngvar Olsen 《Journal of applied phycology》2014,26(4):1869-1878
This paper investigated the assimilation of dissolved inorganic nitrogen (DIN) in Saccharina latissima in proximity to salmon cages in coastal waters. The bioassays were performed on plants from three stations located in the vicinity of a salmon farm (Salmo salar) in exposed waters at Tristein (63° 52′ N, 9° 37′ E) in Central Norway. The growth, the C and N content, and the nitrogen isotope ratios (δ15N) of S. latissima were monitored over 1 year. The DIN concentrations in seawater were higher at the salmon farm stations than at the reference station during the winter, and the N/P ratio at the salmon farm stations was higher from September to January and in June. S. latissima at the salmon farm stations grew faster than at the reference station. The length of S. latissima increased by 50 % when integrated with the salmon farm compared to the reference station. The N content of S. latissima was positively correlated to the DIN concentration in seawater (p?<?0.05), but the increased N supply from salmon did not result in N accumulation in S. latissima at the salmon farm station because of the dilution by a higher growth rate. The δ15N in S. latissima was higher at the salmon farm station from April to June and changed in the direction of the δ15N signature in urine. This indicated that N in S. latissima at the salmon farm station partly originated from the salmon. One hectare of S. latissima may absorb 0.8~1.2 t N during one growth season. Large-scale cultivation of S. latissima should be considered to mitigate the environmental effects of DIN wastes from salmon farms. 相似文献
77.
Silje Forbord Jorunn Skjermo Johanne Arff Aleksander Hand? Kjell Inge Reitan Rasmus Bjerregaard Klaus Lüning 《Journal of applied phycology》2012,24(3):393-399
Saccharina latissima is attractive for industrial cultivation for different usages, such as biofuels, feed supplements, and derivation of chemicals. A continuous supply of kelp sporelings throughout the year may ensure a year-round production of kelp juveniles on ropes. In this study, induction of sporangial areas (sorus portions) on the blade of S. latissima was performed throughout the year at three locations: Trondheim (Norway), Grenaa (Denmark), and Sylt island (Germany). The results indicate that a year-round sorus induction in S. latissima is possible and that this induction is controlled by applying short-day treatment of adult sporophytes throughout the year and by the removal of the basal blade meristem. The artificially induced and released zoospores formed viable sporelings at all seasons, but cultivation in the sea in Norway was successful only during autumn, winter, and spring, while the growth conditions were poor during the summer. The results are important for industrial scale-up and continuous production of kelp biomass. 相似文献
78.
79.
Alvestad S Hammer J Eyjolfsson E Qu H Ottersen OP Sonnewald U 《Neurochemical research》2008,33(2):257-266
A better understanding is needed of how glutamate metabolism is affected in mesial temporal lobe epilepsy (MTLE). Here we
investigated glial–neuronal metabolism in the chronic phase of the kainate (KA) model of MTLE. Thirteen weeks following systemic
KA, rats were injected i.p. with [1-13C]glucose. Brain extracts from hippocampal formation, entorhinal cortex, and neocortex, were analyzed by 13C and 1H magnetic resonance spectroscopy to quantify 13C labeling and concentrations of metabolites, respectively. The amount and 13C labeling of glutamate were reduced in the hippocampal formation and entorhinal cortex of epileptic rats. Together with the
decreased concentration of NAA, these results indicate neuronal loss. Additionally, mitochondrial dysfunction was detected
in surviving glutamatergic neurons in the hippocampal formation. In entorhinal cortex glutamine labeling and concentration
were unchanged despite the reduced glutamate content and label, possibly due to decreased oxidative metabolism and conserved
flux of glutamate through glutamine synthetase in astrocytes. This mechanism was not operative in the hippocampal formation,
where glutamine labeling was decreased. In neocortex labeling and concentration of GABA were increased in epileptic rats,
possibly representing a compensatory mechanism. The changes in the hippocampus might be of pathophysiological importance and
merit further studies aiming at resolving metabolic causes and consequences of MTLE.
Special issue article in honor of Dr. Frode Fonnum. 相似文献
80.
Evaluation of prospective, routine application of Ki-67 immunoquantitation in early CIN for assessment of short-term progression risk 总被引:4,自引:0,他引:4
Kruse AJ Gudlaugsson E Helliesen T Janssen EA van Diermen B Sandvik S Baak JP 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2004,26(3):134-140
OBJECTIVE: To prospectively validate, in early cervical intraepithelial neoplasia (CIN), routine assessment of a previously developed prognostic Ki-67 immunoquantitative progression-risk model. STUDY DESIGN: Two hundred sixty-six consecutive cervical biopsies taken for an abnormal cytologic smear were routinely diagnosed by experienced pathologists as CIN. Ki-67 immunoquantitation was performed routinely by 3 technicians blinded to clinical and pathologic information. Progression of CIN 1-2 to CIN 3 in histologic follow-up biopsies was used as the intermediate end point. RESULTS: In 58 (22%) biopsies, technical shortcomings prevented Ki-67 immunoquantitation, and in 22 biopsies no follow-up was available. The routine diagnosis in the 186 remaining biopsies was CIN 1 = 24, CIN 2 = 56 and CIN 3 = 106. In 52 marker biopsies with expert review diagnosis of CIN 1-2 and adequate follow-up, histologic biopsies revealed CIN 3 in 9 (17%) cases: 9 of 34 (26%) of Ki-67 high-risk and 0 of 18 (0%) of Ki-67 low-risk lesions (log rank = 5.0, P = .03). Routine CIN grade (1 or 2) was not prognostic (P = .65). Eleven (55%) of 20 CIN 1 and 7 of 32 (22%) CIN 2 cases were Ki-67 low risk and none progressed, contrasting with 4 of 9 (44%) progressions of Ki-67 high risk CIN 1s and 5 of 25 (20%) high risk CIN 2s. Expert CIN grades were stronger prognostically than routine CIN grade, but Ki-67 was still stronger. CONCLUSION: Routine Ki-67 immunoquantitative progression prediction in CIN 1-2 is more predictive of CIN 3 in follow-up than are routine and review CIN grades. 相似文献