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SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals.  相似文献   
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Loose sand conducts compressional and surface (Rayleigh) waves at relatively low velocities (95 to 120 meters per second and 40 to 50 meters per second, respectively) compared to other natural substrates. For frequencies between 1 and 5 kilohertz, the specific attenuation factor, Q, for sand is 18. Compound slit sensilla on basitarsal leg segments of sand-dwelling scorpions respond to surface waves generated by movements of insects as far as 50 centimeters away, and tarsal sensory hairs respond to higher-frequency (mostly compressional-wave) components of the signal.  相似文献   
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Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet.  相似文献   
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The California sea otter population was reduced to a small number of animals by fur hunters in the 18th and 19th centuries. The population has partially recovered but is still threatened, largely because of its vulnerability in the event of a major oil spill. The translocation of enough animals to establish a second colony outside the present range has been suggested as a means of reducing the vulnerability of the population.Any population that has been reduced to a small number and then allowed to increase may have lost some of its original genetic diversity. The loss of genetic diversity often results in deleterious effects, such as increased juvenile mortality and reduced fertility. It is therefore of interest to determine the degree of genetic diversity which the California sea otter population should have theoretically lost during its population ‘bottleneck’ and the number of otters which should be translocated in order to avoid substantial loss of genetic diversity in the new colony.Application of some of the concepts of population genetics to the California sea otter indicates that the current population should theoretically retain a large proportion (77%) of whatever genetic diversity existed in the original population and that a new colony resulting from the successful translocation of 50 breeding otters would retain much of the present genetic diversity after 40 years.  相似文献   
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