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1.
Correlations between fine‐scale oceanographic features and aggregations of marine mammals are frequently reported, but the physical forces shaping these relationships are rarely explored. We conducted a series of oceanographic observations and remote sensing surveys of an oceanographic feature near Grand Manan Island known to attract marine mammals on flood tides. We tracked drift drogues from cliff‐top with a theodolite and conducted box‐type surveys with an acoustic Doppler current profiler (ADCP) to assess flow patterns within the oceanographic feature. The feature was also visualized with Synthetic Aperture Radar (SAR) scenes. Drift drogues were advected towards a shear line originating near the northern tip of the island and entrained in one or more eddies downstream. ADCP surveys confirmed the presence of the shear line between rapid easterly flow and slower return flow. As the tide progressed, the shear line extended and manifested a single anti‐cyclonic eddy at its distal end. As the flood tide progressed, northerly flow along the eastern shore of the island intensified and deflected the shear line northwards, shedding the eddy at slack high water. SAR images confirmed the presence of the shearline and eddy system, illustrating the evolution of a wake behind the island on flood tides. Profiles of flow direction and acoustic backscatter revealed secondary flows within the wake consistent with models and observations of other wakes. Oceanographic and remote sensing observations confirm that an island wake is generated by tidal flow past Grand Manan Island and provide an ecological context for the predictable aggregations of odontocete and mysticete cetaceans observed foraging within this region. 相似文献
2.
Forecasting timber production many years in advance has becomea problem of considerable importance in this country becauseof the need to co-ordinate the rapid increase in productionwith the establishment of new timber-using industries. Thispaper describes a change in emphasis in state forest WorkingPlan Inventory methods employed in the predominantly young,coniferous forests of Great Britain and is a development ofthe methods described in a previous paper (Problems ofYield Control and Inventory in British ForestryD.R. Johnston, 1960, Forestry, 33, 1936). Total enumerationof the growing stock is no longer the main objective of forestinventory and the new approach is directed towards (a) assessmentof the productive potential of each subcompartment and (b) theintensive enumeration of sample or index subcompartmentsinitially and at each re-enumeration as a check on growth predictionsand yield control. 相似文献
3.
Isolates of Septoria spp. from cereals were tested for their relative pathogenicity to detached seedling leaves of three cereal species. Each of 23 isolates showed unequivocal adaptation to either oats, or wheat, or barley. Five oat-adapted isolates were from Prince Edward Island, Canada, where S. avenue is prevalent on oats; three were from the UK, where there are few oat crops and where adaptation to oats has not been reported.
Oat-adapted isolates tended to have pycnidiospores of above-average length and could be referred to S. avenae. Wheat-adapted and most barley-adapted isolates had shorter spores and could be referred to S. nodorum. UV-fluorescent pigment was produced on oxgall agar by all wheat-adapted isolates, but only by a minority of oat-adapted and barley-adapted isolates.
It is suggested that adaptation to cereal species is a more useful character than spore length for classifying isolates. 相似文献
Oat-adapted isolates tended to have pycnidiospores of above-average length and could be referred to S. avenae. Wheat-adapted and most barley-adapted isolates had shorter spores and could be referred to S. nodorum. UV-fluorescent pigment was produced on oxgall agar by all wheat-adapted isolates, but only by a minority of oat-adapted and barley-adapted isolates.
It is suggested that adaptation to cereal species is a more useful character than spore length for classifying isolates. 相似文献
4.
The paper describes the methods used in the field and in theoffice to determine the standing volumes and increments of 100-and 130-year old oak in the Forest of Bere, Hampshire, duringworking-plan revision. The figures obtained show that the standingvolumes and increments of sessile oak (Quercus petraea Liebe)are considerably higher than those of pedunculate oak {Q. roburL.) on the three sites investigated, namely, clays, sands, andgravels, while for both species sands appear to be the mostfavourable and gravels the least favourable soil types. Therewas little difference in the mean values for increment and standingvolume between the 100- and the 130-year old pedunculate oak. 相似文献
5.
CHARLES A. KUNTZ DVM MS SPENCER A. JOHNSTON VMD Diplomate ACVS JOHN JACOBSON DVM MS Diplomate ACVA ROBERT A. MARTIN DVM Diplomate ACVS ABVP MARTHA MOON DVM Diplomate ACVR PETER SHIRES BVSc Diplomate ACVS JOHN C. LEE PhD 《Veterinary surgery : VS》1996,25(1):29-39
Controlled cross circulation (CCC) was performed in six pairs of dogs for 45 minutes with aortic cross clamping and cardioplegia. Data were collected in donor dogs at 10 minute intervals three times before, three times during, and three times after CCC and included arterial blood pressure, pulmonary capillary wedge pressure (PCWP), central venous pressure (CVP), cardiac index (CI), heart rate (HR), blood gas analysis, temperature, maximum rate of rise of left ventricular pressure dP/dt max/End diastolic volume (EDV), blood volume (BV), complete blood count (CBC) and activated clotting times (ACT). Pulse pressure (PP), systemic vascular resistance (SVR), oxygen delivery (Do2 ), and left ventricular cardiac work (LVCW) were calculated. Arterial blood pressure, CVP, blood gas analysis, temperature, BV, CBC, and ACT were measured in recipient dogs. During CCC, donor hemodynamic changes resembled those observed in models of acute onset arteriovenous fistulas. Insidious BV shifts can occur despite the use of occlusive roller pumps. After CCC, donor hemodynamics resembled acute blood loss, characterized by decreases in mean arterial pressure (MAP), CVP, PCWP, and CI, and increases in SVR and dP/dt max/EDV. These changes were probably caused by pump imbalance and BV shift to the recipient dog. 相似文献
6.
7.
DUDLEY E. JOHNSTON 《The Journal of small animal practice》1974,15(7):421-435
A procedure for perineal urethrostomy is described in thirty cats. The opening for the stoma is separate from the main skin incision. Haemorrhage from the crura of the penis is controlled by ligation of the crura. Haemorrhage from the corpus cavernosum urethrae is controlled by a tourniquet around the penis, then by compression from the sutures which unite the urethra to the skin. The operation is applicable for primary procedures as well as to the repair of a stenosed perineal urethrostomy. Post-operative catheterization is avoided. The cats have been examined up to 30 months, median 14 months, post-operatively; one of the thirty urethrostomies stenosed at 7 months. Résumé. On décrit un procédé pour urétrostomie chez trente chats. L'ouverture des stoma est séparée de l'incision principale de la peau. On contrôle l'hémorragie de la cuisse du pénis par ligature de la cuisse. L'hémorragie du corps caverneux de l'urètre se contrôle au moyen d'un tourniquet autour du pénis, puis par compression des sutures qui unissent l'urètre à la peau. L'opération est applicable pour des procédés primaires de même que pour la remise en état d'une urétrostomie périnéale stenosée. Une cathétérisation postopératoire est évitée. On a examiné les chats jusqu'à 30 mois, médian 14 mois, de manière postopératoire. Une des trente urétro-stomies a sténosé à 7 mois. Zusammenfassung. Ein Verfahren für perineale Harnröhrenfistelung in 30 Katzen wurde beschrieben. Die Öffnung für das Stoma ist von dem Haupthauteinschnitt getrennt. Blutung von dem Crus penis wird durch Ligatur der Crura kontrolliert. Blutung von dem Corpus cavernosum urethrae wird durch eine Staubinde um den Penis unter Kontrolle gebracht, dann durch Kompression von den Suturen die den Urethra mit der Haut verbinden. Die Operation ist angebracht für primäre Verfahren sowie für Ausbesserung einer stenosierten perinealen Harnröhrenfistelung. Nachoperative Katheterisierung wird vermieden. Die Katzen bis zu 30 Monaten untersucht worden, durchschnittlich 14 Monate, postoperativlich; eine von den 30 Urethrostomien stenosierten um den 7. Monat. 相似文献
8.
RM Jerram CG Warman ESS Davies MC Robson AM Walker 《New Zealand veterinary journal》2013,61(4):197-201
CASE HISTORY A 3-year-old male Labrador retriever was presented with a history of dietary indiscretion followed by vomiting and abdominal pain. CLINICAL FINDINGS AND TREATMENT: Abdominal ultrasonography revealed the presence of a fluid-filled cystic structure in the region of the pancreas. Flocculent, dark fluid was drained from the cystic structure during exploratory celiotomy prior to resection of the lateral cystic wall. Omentum was sutured into the cystic cavity to provide drainage and enhance immune response. A jejunostomy feeding tube was placed. Post-surgical care consisted of antibiotic therapy. The dog was clinically normal at 1 and 7 months post-operatively and the pancreas appeared normal on final ultrasonographic examination. CLINICAL RELEVANCE: This case describes the use of omentum to provide physiological drainage of a pancreatic pseudocyst. This surgical technique may help clinicians manage patients with this condition in the future. 相似文献
9.
Reduction in the mRNA expression of sVEGFR1 and sVEGFR2 is associated with the selection of dominant follicle in cows
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PV Ortega Serrano A Guzmán CG Hernández–Coronado H Castillo‐Juárez AM Rosales‐Torres 《Reproduction in domestic animals》2016,51(6):985-991
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development. 相似文献
10.
Seizures during medetomindine sedation and local anaesthesia in two dogs undergoing skin biopsy 总被引:1,自引:1,他引:0
Each of two dogs presented for multiple skin biopsies were sedated with intravenous medetomidine and lignocaine was injected subcutaneously to provide local anaesthesia for skin biopsy. One dog had a seizure during skin biopsy and again immediately following reversal of medetomidine with atipamezole. The other dog developed seizures 2 h following skin biopsy at which time the medetomidine was reversed with atipamezole. Both dogs were neurologically normal with no history of seizures prior to the procedure and remained neurologically normal for 14 weeks and 9 months, respectively, following the procedure. A drug interaction between the α2 -adrenergic agonist medetomidine and lignocaine is suspected and highlights the potential for seizures following the subcutaneous administration of relatively large doses of lignocaine under medetomidine sedation. 相似文献