Comparison of environmental conditions in the Bering Sea and Davis Strait and the effects on microwave signature returns; March and April, 1979

Aircraft data collected in the Bering Sea in March, 1979 using a 6.6 GH sub z (C Band) microwave radiometer and a 13.9 GH sub z (Ku Band) scatterometer, reinforce the difficulties in interpreting first year ice types found near the ice edge in a marginal ice zone. An ice interpretation scheme using data taken with a 13.3 GH sub z (Ku Band) scatterometer and a 19.4 GH sub z (K Band) radiometer in Davis Strait also shows ambiguity in the first year ice signal and indicates that ice interpretation becomes more difficult near the ice edge and under warmer conditions. This report also compares X Band SAR data taken in Davis Strait with similar imagery collected in the Bering Sea. Ice core samples from the Bering test area offer a basis for speculation on changes in ice morphology which affect the signature return at the ice edge, and help explain the difficulty of the sensors in discerning the two different ice types found on the photography and in the core samples

A Partial Comparative Estimate of Three Methods for the Propagation of Infectious Agents in Developing Chick Embryos

Developing chick embryos have been employed rather extensively in this laboratory for the propagation of various infectious agents during the past three years. The method was used to study the effect of the various agents on chick embryos, to find an easy, efficient, and cheap method of rapid propagation, to aid in the identification of the various agents, and to isolate them or to test for their presence in various filtrates, exudates, and tissues. Thus there was no intention of critical tests of the different methods of chick embryo inoculations to determine which method was most satisfactory for each agent employed. However, partial tests or fairly complete tests have been made in some cases and certain conclusions are apparent

The Bering Sea ice cover during March 1979: Comparison of surface and satellite data with the Nimbus-7 SMMR

During March 1979, field operations were carried out in the Marginal Ice Zone (MIZ) of the Bering Sea. The field measurements which included oceanographic, meteorological and sea ice observations were made nearly coincident with a number of Nimbus-7 and Tiros-N satellite observations. The results of a comparison between surface and aircraft observations, and images from the Tiros-N satellite, with ice concentrations derived from the microwave radiances of the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) are given. Following a brief discussion of the field operations, including a summary of the meteorological conditions during the experiment, the satellite data is described with emphasis on the Nimbus-7 SMMR and the physical basis of the algorithm used to retrieve ice concentrations

Bovine Encephalitis

In the study of sporadic bovine encephalitis it has been necessary to propagate the causative agent by animal passage. This has been rather expensive and time consuming where calves were employed and only slightly less so when guinea pigs were used. In an effort to find a more satisfactory method, chick embryos were inoculated with the peritoneal exudates or the ground liver and spleen of guinea pigs killed during the height of the disease. These materials were known to be high in concentration of the infectious agent. The methods of embroyo inoculation were those usually employed

Double Infantile Spastic Hemiplegia:

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A Study of Some Cases of Streptococcus Infection in Swine

The following is a report of the study of a number of sick hogs from which streptococci were isolated, together with an attempt to evaluate the significance of such microorganisms in diseased swine tissues. The hogs examined were from scattered herds, largely under 8 weeks of age. In some instances nothing was known of the condition of the droves of hogs concerned, either before or after the examinations. In others there was a fairly good history of the condition of the herd and the death losses. In general the cases may be divided into those in which the streptococci were present throughout the body tissues and those in which the infection was confined to the brain and its coverings or largely so. To obtain an understanding of the disease condition encountered in the various herds, some description of individual cases is given

Sporadic Bovine Encephalomyelitis

The infectious agent of sporadic bovine encephalomyelitis has now been propagated for nearly three years in developing chick embryos.This has afforded a convenient method of propagation while studying the causal agent. It is interesting that during all of this time in chick embryos, which represents more than 135 passages in series, there has been no apparent variation in the character of the infectious agent. It is as pathogenic for guinea pigs and cattle as when first isolated. Failure to recognize anything in the tissues of affected animals that would indicate the exact nature of the entity which causes the disease, led to an extension of the histological study to infected chick embryos, especially their membranes and yolk sacs

Suite of simple metrics reveals common movement syndromes across vertebrate taxa

ecause empirical studies of animal movement are most-often site- and species-specific, we lack understanding of the level of consistency in movement patterns across diverse taxa, as well as a framework for quantitatively classifying movement patterns. We aim to address this gap by determining the extent to which statistical signatures of animal movement patterns recur across ecological systems. We assessed a suite of movement metrics derived from GPS trajectories of thirteen marine and terrestrial vertebrate species spanning three taxonomic classes, orders of magnitude in body size, and modes of movement (swimming, flying, walking). Using these metrics, we performed a principal components analysis and cluster analysis to determine if individuals organized into statistically distinct clusters. Finally, to identify and interpret commonalities within clusters, we compared them to computer-simulated idealized movement syndromes representing suites of correlated movement traits observed across taxa (migration, nomadism, territoriality, and central place foraging)