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141.
Adult (Strongylocentrotus purpuratus) purple sea urchins were fed giant kelp (Macrocystis pyrifera) and sea lettuce (Ulva lactuca) macroalgae that were unenriched and enriched with nutrients. Urchins were fed over 10 weeks (5% body weight per day) under laboratory conditions to determine the effect of macroalgae species and treatment (enriched and unenriched) on growth, gonad index and gonad quality. Significant differences were observed when urchins were fed enriched Macrocystis pyrifera (MPE). Gonad weight increased from 0.7 ± 0.1 g (mean ± SD) to 5.9 ± 1 g, and gonad index increase from 3.5 ± 1.5% to 14.9 ± 2.3% over 10 weeks. Significant differences were also noted in gonad quality, and gonad colour and firmness were better in urchins that were fed unenriched M. pyrifera (MPUE) and MPE – whereas texture did not differ between M. pyrifera treatments and unenriched U. lactuca (ULUE). With regard to taste, gonads were sweeter in MPE‐fed individuals. Enriched U. lactuca (ULE) failed to grow gonads significantly; as a result, their quality was unacceptable for the market. These results suggest that S. purpuratus experience increased gonad production and quality in short periods when fed nutrient‐enriched M. pyrifera.  相似文献   
142.
Efforts to improve the efficiency and efficacy of tree structure and crown architecture measurement are necessary to reduce error associated with indirect estimation of volume, which affects biophysical and ecosystem modelling, as well as resource assessment. In this short communication, we test the potential for a commercial SfM-MVS (Structure from Motion coupled with Multiple-View Stereophotogrammetry) software package, Photoscan-Professional, to accurately determine tree height, stem diameter, and eventually volume. SfM is a technique in computer vision, which calculates the 3D position of objects in a scene from a series of photographs. It uses a technique assuming that an object in a 3D scene is located on a vector between the image of the object in the camera and the object itself. The technique allows the construction of a 3D pointcloud, such as the one produced by laser technologies – terrestrial or airborne LiDAR. SfM requires no camera calibration or control points to construct an initial model. Moreover, it is a low-cost alternative to laser technologies. The second part of our method – MVS – is a visualization technique that reconstructs a 3D textured mesh of the scene from the SfM-derived pointcloud and RGB photographs. As a proof of concept, our methods were limited to two scenarios: (1) a single potted tree in a lab environment, where exact measurements could be made, and (2) two trees of different species and size in natural environments to test feasibility outside the laboratory. Precise measurements of tree height and stem diameter were compared with estimates obtained from the 3D model created using SfM-MVS. The results indicate that the SfM method is a promising – and inexpensive – alternative to terrestrial LiDAR and 3D scanners. Tree height estimates had error of 2.59%, while stem diameter estimates had error of 3.7%. The MVS algorithm used in this study was developed for plan surfaces such as topography or ‘compact’ objects and does not provide a representative 3D mesh for slender trees, although it works well for large stems. The authors link this disparity to the complex branching structure of trees.Future work requires (1) the development of effective automated volume reconstruction software specific to trees, and (2) the validation of the wide-scale applicability of the technology, which must include trees of various size, species, and growth forms. Moreover, future testing must include more complex environments, such as heterogeneous urban sites or closed-canopy forest sites where the proximity of other features may limit the utility of the new technology.  相似文献   
143.
Desmopressin (1-deamino-8-d-arginine vasopressin, also known as DDAVP) is a safe haemostatic compound capable of inhibiting lymph node and lung metastasis in a mouse model of mammary tumour manipulation and surgical excision. The aim of this study was to test the efficacy and safety of perioperative DDAVP (1microg/kg) in surgically treated bitches with mammary gland tumours (MGT). Twenty-one, otherwise healthy, intact bitches, with malignant MGT stage III or IV were randomly allocated to DDAVP (n=11) or placebo (n=10) groups. En bloc mastectomy of the affected gland/s was performed. DDAVP had a significant beneficial effect on disease-free period (P<0.01) and overall survival time (P<0.05). No side effects were seen in any of the cases. Whatever the mechanism of action, it seems that DDAVP may have a novel use in cancer surgery to minimise spread or survival of residual malignant cells. Additional, large scale controlled trials are required to fully evaluate this adjuvant pharmacological protocol.  相似文献   
144.
In order to investigate methods for controlling systemic bacterial coldwater disease (CWD), bacteriophages that infect Flavobacterium psychrophilum were isolated by the enrichment method from pond water collected from Japanese ayu farms. The five phages isolated were classified as members of Myoviridae (PFpW-3, PFpC-Y), Podoviridae (PFpW-6, PFpW-7), and Siphoviridae (PFpW-8) and had highly variable patterns of infectivity for different F. psychrophilum isolates (n = 128). The stability tests of the phages in different waters, pHs and temperatures were assessed, and the results indicated that none of the phages were affected by ayu farm conditions. Among the phages, PFpW-3 had high infectivity for F. psychrophilum isolated from ayu and other fish and demonstrated sufficient survivability in the stability tests. Thus, PFpW-3 and its indicator strain N2-3 were inoculated into cytophaga broth at different doses of multiplicity of infection (MOI) and proved to be efficient for the reduction of bacterial growth. This study may be the basis for a further evaluation of phage therapy in the treatment of CWD in Japanese ayu farms.  相似文献   
145.
Landscape Ecology - The effect of landscape complexity on biodiversity is an important topic in landscape ecology, and spatial scale is key to understand true species-landscape relationships. We...  相似文献   
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The Iberian pig is an autochthonous breed of the Mediterranean area, reared extensively in the central and southern areas of Spain and Portugal and that is known worldwide for the production of Iberian ham. The characteristics of the Iberian ham are related to its abundance of intramuscular fat, owing to the high capacity of the pig to accumulate fat under its skin and between the muscular fibres. This ability to store excess fat enables survival during periods of scarcity and it has been found in other antique animal breeds and even in humans, being named as the thrifty genotype. The reproductive management of the Iberian pig, in spite of a lack of accurate information unlike in other swine breeds, is based on the assumption of lower reproductive precocity and efficiency than the modern commercial breeds. The current study characterized and compared the onset of puberty in gilts of Iberian breed and meat commercial crosses (Large White × Landrace) reared in the same conditions by assessing weekly plasma progesterone profiles. At the end of the experimental period, when the gilts became 180 days old, the percentage of Iberian females that had reached puberty was 72.2%, with a mean age and weight of 160.5 ± 2.6 days and 92.9 ± 4.7 kg, respectively. The percentage of Large White × Landrace cross‐breed females reaching puberty at 180 days was only 15% (p < 0.05). The mean age and weight were 165.0 ± 4.1 days and 107.8 ± 2.2 kg (p < 0.05), respectively. Thus, converse to the traditional assumption, onset of puberty was advanced in Iberian gilts. These results are important for the reproductive management of the Iberian pig but, at the same time, may set the basis for future studies on the metabolism–reproduction link and, specifically, on the possible relationship between earlier accumulation of fat and attainment of puberty.  相似文献   
149.
A 7‐year‐old, 34‐kg, neutered male Labrador retriever was presented with a 1‐year history of intermittent sneezing with occasional left‐sided epistaxis. CT revealed a mass in the left nasal cavity. Histopathological analysis of rhinoscopy‐guided tissue biopsies was consistent with chronic necrotic and ulcerative rhinitis. Surgical debridement by ventral rhinotomy was subsequently performed and histopathological diagnosis was leiomyoma. Complete resolution of the nasal discharge and reduced sneezing frequency were observed after surgery. Fourteen months postoperatively, CT detected no regrowth of the mass.  相似文献   
150.
OBJECTIVE: To quantify the neuromuscular blockade (NMB) produced by atracurium in either sevoflurane or propofol-anaesthetized dogs. ANIMALS: Twelve healthy, female adult mixed-breed dogs weighing 13 +/- 3 kg (range 10-22 kg). MATERIALS AND METHODS: Three doses of atracurium (0.1, 0.2 and 0.3 mg kg(-1)) were tested at 1-week intervals. Anaesthesia was induced with inhaled sevoflurane or intravenous propofol and maintained with end-tidal sevoflurane concentrations of 1.95% (1.25 x MAC) or propofol 0.6 mg kg(-1) minute(-1) respectively. Acceleromyography and train-of-four stimulation of the fibular nerve were used for the assessment of NMB. The percentage depression of the first twitch (T1) and the fourth to the first twitch ratio (T4/T1), the maximum degree of neuromuscular block achieved and surgical muscle relaxation were recorded. Before and during neuro muscular blockade (at 10 minute intervals) body temperature, ECG, arterial blood pressure, inspired and expired CO2 concentrations and SpO2 were recorded. RESULTS: Atracurium produced a dose-dependent duration of NMB in both propofol and sevoflurane-anaesthetized dogs. Duration of block was longer in dogs anaesthetized with sevoflurane. All studied doses of atracurium caused twitch depression > or =95% with little or no cardiovascular changes. CONCLUSIONS: Sevoflurane produces a clinically relevant potentiation of atracurium-induced NMB in dogs compared with propofol. CLINICAL RELEVANCE: Significant differences in the potentiation of NMB drugs are encountered with commonly used anaesthetics in the dog.  相似文献   
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