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61.
Crow  P; Benham  S; Devereux  BJ; Amable  GS 《Forestry》2007,80(3):241-252
Archaeological surveys in woodland have always been problematicand many woodlands contain an unrecorded archaeological resource.For other types of rural landscape, aerial photographs are oftenused to map archaeological features but woodland cover has alwaysimpeded such disclosure. Remote sensing methods are rapidlyevolving and are used both within forestry and archaeologicaldisciplines for a range of applications. This paper considersthe exciting application of the remote sensing technique ofairborne Light Detection and Ranging (LiDAR) to reveal archaeologicalevidence previously hidden below a woodland canopy. Our researchshows how different types of woodland canopy and understoreyvegetation greatly influence the effectiveness of the LiDARto perform these surveys. A simple, visual vegetation mappingassessment is tested and its ability to predict the potentialof the LiDAR considered. This work highlights the importanceof vegetation awareness when considering both a new LiDAR surveyfor a woodland, and when interpreting the data. Simple estimatesof LiDAR penetration of the woodland canopy and understoreyvegetation can be used to predict the effectiveness of a LiDARsurvey in disclosing archaeological evidence and aid the interpretationof results.  相似文献   
62.
Coppins  BJ; Coppins  AM 《Forestry》2006,79(3):249-259
During the last 30 years, 434 epiphytic lichen taxa have beenrecorded from the native pinewoods of Scotland. Of these lichens,about 219 have been recorded from the bark, lignum or stumpsof pine (Pinus sylvestris) itself. Eighteen species are, inthe British Isles, confined to these native pinewoods, whichare themselves confined to the Scottish Highlands. A resumeis presented of the habitats and niches available to lichensin the native pinewoods, using examples of the most characteristicspecies for each. The ‘pinewood habitat’ for epiphyticlichens is by no means restricted to pine, but also includesassociated trees, shrubs and subshrubs, especially birch, rowan,holly, aspen, juniper and heather. The strong east–westvariation in the composition of the lichen flora is outlined.By comparison of species lists from pinewood stands of knownancientness with those from mature plantations distant fromthe ‘core’ pinewoods, an additional c. 60 speciescan be considered as indicative of an ecological continuityof the pinewood habitat. From this pool of c. 77 species, aNative Pinewood Index of Ecological Continuity is presentedas a useful tool for biodiversity assessments of pinewoods.  相似文献   
63.
湖南省山茶属红山茶组植物园林应用初探   总被引:1,自引:0,他引:1  
湖南省山茶属红山组植物种类较多,共13种1变种,约占国产数的23.6%,居全国第二,仅次于四川省.笔者在实地调查和查阅大量文献的基础上认为其为优良的乡土木本花卉,观赏价值高,园林应用前景广阔,值得大力推广.在此基础上,笔者对其园林应用进行了初步探讨.  相似文献   
64.
AIMS: To review results of the ventral approach for mandibular and sublingual sialoadenectomy for the treatment of sialocoeles associated with the mandibular and sublingual salivary glands in the dog, and to determine rates of recurrence and complication following this procedure.

METHODS: Thirty-nine dogs with 41 sialocoeles that underwent surgical intervention were retrospectively evaluated with respect to signalment, aetiology, location of sialocoeles, duration of clinical signs, treatment prior to referral, post-operative use of antibiotics and drains, complications, and recurrence.

RESULTS: The mean age at the time of surgery was 5.1 (SD 3.8) years, and duration of clinical signs 6.6 (SD 10.6) months. Long-term follow-up was available for 31 dogs; the minimum was 8 months and mean 47.7 (SD 25.8) months post-surgery. There was no recurrence of sialocoeles following the ventral approach for mandibular and sublingual sialoadenectomy. Post- operatively, 6/35 (17%) cases developed a seroma at the surgical site. No breed or sex predisposition was determined. The cause of the sialocoele was unknown in 36/41 (88%) cases.

CONCLUSIONS AND CLINICAL RELEVANCE: Excellent clinical results were achieved with a low rate of complications using the ventral approach for mandibular and sublingual siaload- enectomy. The ventral approach is recommended to minimise the risk of recurrence of sialocoeles.  相似文献   
65.
Melatonin is thought to be the main molecule that transmits the signal of seasonal change to the neuroendocrine system in seasonal breeding species. Melatonin exerts its effects through specific melatonin receptors, MTNR1A and MTNR1B. In the present study, six native goat breeds in China and one introduced goat breed were analysed to investigate the relationship between the genetic polymorphism of receptor genes and seasonal reproduction. Sequencing results showed that there were five polymorphic mutations in the MTNR1A gene and two in the MTNR1B gene. In the MTNR1A gene, genotypes AA, AB and BB for 424C>T and genotypes CC, CD and DD for 589C>A were observed in these goat breeds. In all six native goat breeds, only genotype AA was detected. In the MTNR1B gene, genotypes EE, EF and FF for 1179G>A and genotypes GG, GH and HH for 1529A>G were detected. However, in Gulin Ma goats, the genotypes EE and HH were not found. Moreover, the base of G at position 1179 and A at position 1529 were linked (By Arlequin ver 3.1, Zoological Institute, Berne, Switzerland, http://cmpg.unibe.ch/software/arlequin3 ,D′ = 0.7496, r2 = 0.4421, χ2 = 489.8679, p = 0.000). Among these mutations, no amino acid change was found in MTNR1A, while both of the mutations in MTNR1B gene caused amino acid changes of R222H and S339G, respectively. The structural analysis showed that the R222H mutation occurred in the first amino acid residue of the third cytoplasmic loop, and the S339G mutation was located in the carboxyl terminus of the protein. In terms of seasonal breeding, all the genotypes we detected showed a similar kidding frequency distribution trend with a higher frequency in May–August than in January–April and in September–December. This suggests that the relationship between the polymorphisms in the MTNR1A and MTNR1B genes and seasonal breeding could not be established.  相似文献   
66.
Analgesic agents were administered perioperatively to an eight-year-old Springer Spaniel undergoing amputation of its right thoracic limb. The amputation was carried out due to a painful, infiltrative and poorly differentiated sarcoma involving the nerves of the brachial plexus. A combination of pre-emptive and multimodal perioperative analgesic strategies was used; including intravenous (IV) infusions of fentanyl, morphine, lidocaine and ketamine.  相似文献   
67.
A total of 696 tibial plateau leveling osteotomy (TPLO) procedures were performed over a 30-month period following TPLO training. The overall complication rate was 18.8%. Complications were classified as perioperative (1%), short-term (9.3%), and long-term (8.5%). Examples of complications encountered during the study were hemorrhage, swelling at the incision site, premature staple removal by the dog, tibial tuberosity fracture, patella tendon swelling, and implant complications. Based on the rate of complications observed, clinical outcomes of TPLO procedures within 30 months of TPLO training were considered good.  相似文献   
68.
69.
More than 85 percent of Australian terrestrial genera with a body mass exceeding 44 kilograms became extinct in the Late Pleistocene. Although most were marsupials, the list includes the large, flightless mihirung Genyornis newtoni. More than 700 dates onGenyornis eggshells from three different climate regions document the continuous presence of Genyornis from more than 100,000 years ago until their sudden disappearance 50,000 years ago, about the same time that humans arrived in Australia. Simultaneous extinction of Genyornis at all sites during an interval of modest climate change implies that human impact, not climate, was responsible.  相似文献   
70.
An American Cocker Spaniel with low plasma taurine concentration (< 2 nmol/mL) was presented with dyspnoea associated with pulmonary oedema and a left ventricular shortening fraction of 9%. Emergency therapy with furosemide, dobutamine, nitroglycerine and oxygen supplementation led to a good response. Chronic therapy was started with enalapril, furosemide, digoxin and taurine. Improvement in all echocardiographic indices were noted over a 22 week follow-up, most notably an increase in left ventricular shorteningfraction to 20%, a decrease of E-point septal separation from 14 mm to 7 mm and marked left ventricular remodelling. This degree of improvement in myocardial function may represent a direct link between dilated cardiomyopathy in the American Cocker Spaniel andplasma taurine deficiency. Alternatively, this response may reflect a breed-related cardiomyopathy with a natural history and therapeutic response not commonly seen in the morecommon large breed cardiomyopathy presentations.  相似文献   
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