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31.
A retrospective review of case records of ultrasonography and necropsy outcomes of 62 koalas was used to investigate the accuracy of ultrasonography in assessing koala urogenital tract structural disease at the Port Macquarie Koala Hospital. The results showed high concordance, supporting ultrasonography as an effective tool for evaluating structural disease of the koala urogenital tract, most commonly seen with chlamydiosis. The study also illustrates the advances benefiting animal welfare that can be made by wildlife carer groups through using a scientific, evidence‐based approach.  相似文献   
32.
Subduction zones play critical roles in the recycling of oceanic lithosphere and the generation of continental crust. Seismic imaging can reveal structures associated with key dynamic processes occurring in the upper-mantle wedge above the sinking oceanic slab. Three-dimensional images of reflecting interfaces throughout the upper-mantle wedge above the subducting Tonga slab were obtained by migration of teleseismic recordings of underside P- and S-wave reflections. Laterally continuous weak reflectors with tens of kilometers of topography were detected at depths near 90, 125, 200, 250, 300, 330, 390, 410, and 450 kilometers. P- and S-wave impedances decreased at the 330-kilometer and 450-kilometer reflectors, and S-wave impedance decreased near 200 kilometers in the vicinity of the slab and near 390 kilometers, just above the global 410-kilometer increase. The pervasive seismic reflectivity results from phase transitions and compositional zonation associated with extensive metasomatism involving slab-derived fluids rising through the wedge.  相似文献   
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Estrogen and its receptors are essential for sexual development and reproduction. Oestrogen receptor alpha (ERα) is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene ESR1 (oestrogen receptor1) responsible for better fertility. ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. The present study was undertaken to investigate the expression and presence of ESR1 gene in fertile and low-fertile male goat breeds. We identified ESR1 gene through various molecular tools. Genotyping was carried out by high resonance melting analysis using Roche Light Cycler 480(LC-480) system and found three different genotypes. Genotypic frequency-AA (blue-0.67), BB(Red-0.2), AB(Green-0.08) with allele frequency A(0.71 and B (0.29). The predominance of this gene in head of epididymis in fertile bucks was confirmed by SDS-PAGE, Western blotting and immunohistochemistry. From the results, we corroborated that the present study provides a useful and effective way to predict male fertility in goat breeds, which in turn increases the percentage of fertility in flock leading to more number of offspring in a kidding season.  相似文献   
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A sheep trial was performed to standardise a coproantigen reduction test (CRT) protocol for the diagnosis of resistance to triclabendazole (TCBZ) in Fasciola hepatica). The CRT employs the BIO K201 Fasciola coproantigen ELISA (Bio-X Diagnostics, Jemelle, Belgium) to test for the presence of F. hepatica coproantigens in a faecal sample. If it is coproantigen-positive, the CRT protocol recommends that faecal samples are re-tested for coproantigens at 14 days post-treatment (dpt), with negative testing at this point indicating TCBZ success. Initial work aimed to confirm the sensitivity of the BIO K201 ELISA for Fasciola infection and investigate whether coproantigens represent a robust reduction marker of TCBZ efficacy. Thirty-eight, indoor-reared sheep were artificially infected with F. hepatica isolates known to be susceptible (Cullompton) and resistant (Sligo) to TCBZ action, respectively. Treatment was administered at 12 weeks post-infection (wpi), with 2 sheep groups, infected with each isolate, culled at 2 and 4 weeks post-treatment (wpt), respectively. Necropsy was performed to confirm treatment efficacy. Individual faecal samples were collected twice-weekly throughout the trial period. Additional work focused on the effect of temperature on faecal sample collection and storage. Faecal samples collected from sheep positive for F. hepatica infection were sub-sampled and left at room temperature. Individual sub-samples were tested by ELISA on consecutive days and these readings compared to the original test result on the day of collection. In addition, ELISA values were compared between faecal sub-samples prepared on the day of sampling and post storage at -20°C. Also, an immunocytochemical study was performed to determine the tissue site of origin of the coproantigen protein in the fluke. Results showed that the BIO K201 ELISA was sensitive for Fasciola coproantigens, with coproantigens detectable from 5 wpi onwards. The suitability of coproantigens as a diagnostic marker of TCBZ efficacy was supported by the absence and presence of coproantigens in TCBZ-treated Cullompton (TCBZ-susceptible) and Sligo (TCBZ-resistant) F. hepatica infections at 2 and 4 wpt, respectively. Study results suggest that low to moderate temperature has little, if any, impact on coproantigen stability in faecal samples, but that higher temperatures may have. Immunolabelling for the coproantigen showed that it was specific to the gastrodermal cells of both adult and juvenile flukes.  相似文献   
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An unknown compound isolated chromatographically from extracts of rhizome tissues of quackgrass which had previously been treated with dalapon resembled phenol. The compound reduced silver nitrate and had an ultraviolet absorption maximum similar to that of phenol and a positive reaction to the LeRosen test. Melting points and infrared absorption maxima for phenylurethane and alpha-naphthylurethane derivatives of the unknown matched those for the same phenol derivatives.  相似文献   
39.
Net ecosystem carbon dioxide exchange was measured in two contrasting peatlands in northern Alberta, Canada using the eddy covariance technique during the growing season (May–October). Sphagnum spp. made up approximately 66% of the total LAI (1.52 m2 m−2) at the poor fen and the total N content of Sphagnum capitula was 7.8 mg g−1 at the peak of the growing season. In contrast, the dominant plant species at the extreme-rich fen site, the perennial sedge, Carex lasiocarpa, accounted for approximately 60% of the total LAI (1.09 m2 m−2), and had leaf total N content of 19.3 mg g−1 at peak biomass. In addition, the peak aboveground biomass was higher at the poor fen (230.9 g m−2) than at the extreme-rich fen (157.1 g m−2). Both sites had maximum daily rates of net CO2 uptake of approximately 5 μmol m−2 s−1, and typical nighttime rates of CO2 loss of approximately 2 μmol m−2 s−1 during the peak of the growing season. Calculations of maximum photosynthetic and respiratory capacity were consistently higher at the extreme-rich fen. The poor fen was a net sink for CO2 during 4 of the 6 months (peaking at 44 g C m−2 in July), while only slight net losses of CO2 (3 g C m−2) occurred in May and September. In contrast, the extreme-rich fen was calculated to be a significant net sink for CO2 only during 2 months of the growing season (peaking at 30 g C m−2 in August), while significant net losses of CO2 occurred in May (8 g C m−2) and in October (13 g C m−2). The plant species at the poor fen site were active earlier and later in the growing season, while it took longer for C. lasiocarpa to develop leaf tissue, and leaf senescence and reduction in photosynthetic activity occurred earlier in the fall at the extreme-rich fen. When integrated over the 6-month growing season, the poor fen was a net sink (90 g C m−2) that was three times larger than the extreme-rich fen (31 g C m−2). The ratio of cumulative total ecosystem respiration to gross primary production was 0.7 at the poor fen and 0.9 at the extreme-rich fen.  相似文献   
40.
Wilderness can be defined in both political and popular terms. Political wilderness is designated by a government and given a resultant protected status. Popular, or perceived, wilderness is wilderness as defined in the mind of an individual. We investigated the potential for maps of perceived wilderness created in a geographic information systems (GIS) environment to be used in the management of politically designated wilderness and other protected areas. Using data gathered through a questionnaire survey of the wilderness preferences of recreational users of Colorado's San Juan National Forest (SJNF), we divided users into four “purism groups” that reflect the discrimination demonstrated by the user in personally defining the wilderness setting. We determined specific conditions considered by each group to be undesirable in the wilderness setting, and using GIS, mapped the extent of perceived wilderness in the SJNF for each purism group with a method that excluded areas of the National Forest demonstrating undesirable conditions. We assessed the potential for maps of perceived wilderness to be used in the management of political wilderness and other protected areas by comparing the extent of perceived wilderness in the SJNF to recreation opportunity spectrum (ROS) class groupings, the extent of politically designated wilderness, and inventoried roadless areas in the National Forest.  相似文献   
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