Microwave Radiometers     

Barath FT  Barrett AH  Copeland J  Jones DE  Lilley AE 《Science (New York, N.Y.)》1963,139(3558):908-909

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Letter to the editor     

Barrett EW 《Science (New York, N.Y.)》1971,173(4001):983

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The u.s. Census     

Barrett RE 《Science (New York, N.Y.)》1994,265(5181):2106

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Discovery of hydroxyl radio emission from infrared stars     

Wilson WJ  Barrett AH 《Science (New York, N.Y.)》1968,161(3843):778-779

Radio spectral line emission from hydroxyl radicals has been detected from four infrared stars. The emission from the infrared star NML Cygni at 1612 megahertz is the strongest radio emission line yet detected. Sixteen other stars with infrared excesses showed no detectable hydroxyl radio emission.  相似文献   

Soundscape in a context of acoustic and landscape ecology     

Barry Truax  Gary W. Barrett 《Landscape Ecology》2011,26(9):1201-1207

Soundscape ecology is being proposed as a new synthesis that leverages two important fields of study: landscape ecology and acoustic ecology. These fields have had a rich history. Running “in parallel” for over three decades now, soundscape ecology has the potential to unite these two (among other) fields in ways that provide new perspectives on the acoustics of landscapes. Each of us was involved in the “birth” of these two fields. We each reflect here on the rich history of landscape ecology and acoustic ecology and provide some thoughts on the future of soundscape ecology as a new perspective.  相似文献   

Potential of a national monitoring program for forests to assess change in high-latitude ecosystems     

Tara M. Barrett  Andrew N. Gray 《Biological conservation》2011,(5):1285-1294

Broad-scale monitoring in Alaska has become of increasing interest due to uncertainty about the potential impacts of changing climate on high-latitude ecosystems. The Forest Inventory and Analysis (FIA) program is a national monitoring program for all public and private forestlands in the US, but the program is not currently implemented in the boreal region of Alaska. We provide an overview of the strengths and weaknesses of the FIA system for monitoring the potential impact of climate change on Alaska’s species, communities, and ecosystems. The primary strength of the system is a scientifically rigorous design-based statistical estimation method that produces estimates of forest attributes with known sampling error and quantifiable measurement error. The weaknesses of the system include low power for small area estimates, lack of spatial context and contiguity, and difficulty in inferring causality of factors when changes in monitored attributes are detected.Climate change is expected to impact many components of boreal ecosystems, but for most indicators the direction and magnitude of change are difficult to predict because of complex interactions among system components. Status and trend information provided by FIA monitoring that could be helpful to conservation decisions includes abundance and rarity of vascular plants, invasive species, biomass and carbon content of vegetation, shifting vegetation species distribution, disturbance frequency, type, and impact, and wildlife habitat characteristics. Because of unique factors such as the low level of infrastructure, modifications to the FIA monitoring system used in the conterminous US have been proposed for Alaska. Remote sensing data would play a greater role in meeting monitoring objectives, and sampling intensity of field plots would be reduced. Coordination with other national, regional, and local monitoring efforts provides potential for increased understanding of change in boreal ecosystems at multiple scales.  相似文献   

Genetic characterisation of oak seedlings, epicormic, crown and micropropagated shoots from mature trees by RAPD and microsatellite PCR     

C. Barrett  F. Lefort  G.C. Douglas 《Scientia Horticulturae》1997,70(4):319-330

DNA was isolated from seedlings of Quercus robur, collected from a single provenance, and from epicormic, crown shoots and in vitro shoots from a single tree of Q. petraea using a CTAB method of extraction. DNA was obtained in sufficient quantity and purity, from 13 out of 30 seedlings, and from all isolations from epicormic and in vitro shoots (2.5–10.0 μg/g fresh/ weight). Smearing was minimised at a primer concentration of 0.12 μM with Taq polymerase at 0.5 unit/reaction. Nine primers produced 142 bands, 28 of which were polymorphic. A similarity index showed that 11 seedlings were closely related with high coefficients (0.85–0.90), but each could be identified from another using only 9 primers (OPA-02 and -05, OPG-04 and -05, OPE-01, -02, -03, -08, -09). DNA was isolated from crown, epicormic and in vitro leaves originating from a single 150-yr old tree of Q. petraea and analysed by randomly amplified polymorphic DNA (RAPD) and microsatellites. With each primer, a characteristic RAPD pattern was obtained, and it was common to all six epicormic shoots derived from different parts of a single branch of this tree; also to the shoots from the crown of the same tree with OPE1 OPA-05, OPA-08, OPA-01, OPA-02, OPA-04, OPA-05, OPG-02, OPG-10, OPE-12. Similarly, the RAPD pattern obtained from shoot cultures in vitro, derived from individual nodes of epicormic shoots produced by six different branch segments, were uniform for each of 15 primers. This work was repeated using microsatellite PCR. Three microsatellite loci AG16, AG 1/2 and AG 1/5 were amplified by PCR. It showed a uniformity of these microsatellite loci in shoots from the crown of the tree, and from epicormic shoots cultures derived from six different sections of branch.  相似文献   

Peste des petits ruminants in Ethiopian goats     

P. L. Roeder  G. Abraham  G. Kenfe  T. Barrett 《Tropical animal health and production》1994,26(2):69-73

Summary An outbreak of disease characterised by fever, ocular and nasal discharge, coughing and sneezing, oral necrosis, diarrhoea, enteritis and pneumonia in goats was shown by the use of specific cDNA probes to have been peste des petits ruminants, confirmed for the first time in Ethiopia. Both morbidity and mortality rates were high in goats but sheep were not affected.

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Peste De Pequeños Rumiantes En Caprinos En Etiopia

Resumen Se presentó por vez primera en Etiopía, un brote de peste de pequeños rumiantes, la que fue detectada mediante el uso de de sondas cADN especificas. La enfermedad se caracterizó por fiebre, descargas ocular y nasal, tos, estornudos necrosis oral, diarrea, enteritis y neumonia. Tanto la morbilidad como la mortalidad fueron altas en caprinos pero no en ovinos.

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Peste Des Petits Ruminants Chez Des Chevres Ethiopiennes

Résumé Une maladie caractérisée par de la fièvre, des écoulements nasal et oculaire, de la toux et des éternuements, une nécrose orale, de la diarrhée, de l'entérite et une pneumonie est apparue chez des chèvres. L'utilisation de sondes à ADNc spécifiques a montré qu'il s'agissait de la peste des petits ruminants, confirmée pour la première fois en Ethiopie. Les taux de morbidité étaient élevés chez les chèvres mais les moutons n'étaient pas affectés.

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Ovariectomy as treatment for granulosa cell tumor in a heifer   总被引：1，自引：0，他引：1  

R R Leder  V M Lane  D P Barrett 《Journal of the American Veterinary Medical Association》1988,192(9):1299-1300

A granulosa cell tumor in a 15-month-old heifer was associated with abnormal udder development, relaxation of the pelvic ligaments, and nymphomanic behavior. After surgical removal of the tumor, the anatomic changes were reversed, and the nymphomanic behavior subsided. The heifer conceived 3 times thereafter and became a productive dairy cow. In previously reported cases of granulosa cell tumor, ovariectomy was unsuccessful in returning the cow to normal breeding.  相似文献   

Financial analysis of a clinical trial comparing simple estrus detection with estrus detection after prostaglandin-based appointment breeding in a commercial dairy herd in California, USA     

Barrett D. Slenning 《Preventive veterinary medicine》1994,18(4):239-257

An economic analysis of the outcomes from a clinical trial on dairy cow reproduction was performed. The trial compared two prospective cohorts from a California dairy herd of 670 cows: (1) a cohort of 56 cows initially treated with prostaglandin-F2 and appointment inseminated at 72 and 96 h post-treatment, followed in 7 days by estrus detection based breeding (PT); (2) a cohort of 53 cows that was managed strictly for estrus detection based breeding (HD). There were no significant differences between the cohorts for days in milk at conception, services per conception, or time to events. The economic analysis consisted of three parts: (1) a partial budget analysis of the two breeding strategies; (2) a deterministic decision analysis of the two practices; (3) a stochastic evaluation of the strategies. Both the deterministic and stochastic analyses used time value of money calculattions PT insemination cost the farm approximately $32 compared with an HD cost of approximately $17. However, the costs of getting the average animal pregnant were approximately respectively. Expected monetary values were $588 and $707 for PT and HD strategies, respectively. The stochastic decision analysis evaluated risks and return over 1000 simulations. It suggested that in 73% of cases an HD strategy will produce expected monetary values $170 more than the PT strategy, in 10% of cases the two will be within 4% in yield, and in 17% the PT strategy will yield $95 more than an HD program. Sensitivity analysis suggested that conception rates to estrus detection based breedings are not likely to alter the decision. However, conception rates to the appointment breeding program in conjunction with the elapsed time postpartum when the decision to breed is implemented and estrus detection rates can cause the PT strategy to be optimal. Situations where this might occur are discussed.  相似文献