Flow-field observations of a tidally driven island wake used by marine mammals in the Bay of Fundy, Canada

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.     

Developments in Yield Control and Inventory in British Forestry

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 Forestry’—D.R. Johnston, 1960, Forestry, 33, 19–36). 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.     

Identification of oat-adapted isolates of cereal Septoria in the UK using a detached leaf technique

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.     

AN ENUMERATION OF THE MATURE OAK IN THE FOREST OF BERE

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.     

Controlled Cross Circulation in Dogs: Effects on Donor Hemodynamics

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.     

Feline urethrostomy—a critique and new method

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.     

Peroxidase activity and propanil degradation in soil*

The herbicide N-(3,4-dichloropxhenyl)-propionamide (propanil) and a metabolite of propanil, 3,4-dichloroaniline (DCA), were mixed with Nixon loam soil which was subjected to moisture and air-drying treatments. Degradation of propanil was altered by subjecting the treated soil samples to storage conditions of moisture, drying and chloroform. The peroxidase activity in fresh soil was very low when soil samples were collected during the cold season. The amount of 3,3′,4,4′- tetrachloroazobenzene (TCAB) produced from DCA increased with a simultaneous increase in the peroxidase activity in preincubated soil where carbon and nitrogen sources were added.     

Minimum Inhibitory Concentration and Postantibiotic Effect of Amikacin for Equine Isolates of Methicillin-Resistant Staphylococcus aureus In Vitro

Objective— To report the minimum inhibitory concentration (MIC) of amikacin sulfate for equine clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and characterize the initial kill and duration of the postantibiotic effect (PAE) for selected strains.
Study Design— Experimental study.
Methods— Isolates of MRSA (n=35) had their amikacin MIC determined using the E-test agar diffusion method. Two isolates with MICs>256 μg/mL limit were further characterized using broth macrodilution. Six distinct isolates with amikacin MICs of 32, 48, 128 (2 isolates) and 500 (2 isolates) μg/mL had PAE determinations made over a range of amikacin concentrations from 31.25–1000 μg/mL using standard culture-based techniques.
Results— Median MIC of the 35 isolates was 32 μg/mL (range 2 to >256 μg/mL). Mean PAE of selected MRSA strains had an overall mean (all amikacin doses) of 3.43 hours (range 0.10–9.57 hours). PAE for MRSA exposed to amikacin at 1000 μg/mL was 6.18 hours (range 3.30–9.57 hours), significantly longer than that for all other concentrations ( P <.0001). There was no statistically significant effect of isolate MIC on PAE.
Conclusions— Isolates had a wide range of MIC; however, growth of all 6 selected strains were inhibited within the range of concentrations tested, including 2 strains with MICs of 500 μg/mL. PAE duration was not influenced by the MIC of amikacin but was significantly longer with treatment at 1000 μg/mL than at lower concentrations.
Clinical Relevance— Clinical isolates of MRSA are susceptible to amikacin at concentrations achieved by regional perfusion: however, the modest duration of PAE observed suggest that further laboratory and in vivo evaluation be conducted before recommending the technique for clinical use.