Climate change. A single climate mover for Antarctica     

Kerr RA 《Science (New York, N.Y.)》2002,296(5569):825-826

  相似文献   

Paleontology. Earliest signs of life just oddly shaped crud?     

Kerr RA 《Science (New York, N.Y.)》2002,295(5561):1812

  相似文献   

Seismology. Whole lotta shakin' in Alaska,as predicted     

Kerr RA 《Science (New York, N.Y.)》2002,298(5597):1316

  相似文献   

Yersiniosis and trace element deficiency in a dairy herd     

McLennan MW  Kerr DR 《Australian veterinary journal》2000,78(1):28-30

  相似文献   

PLANETARY SCIENCE: Most-Common Meteorites Find a Home Among the Asteroids     

Kerr RA 《Science (New York, N.Y.)》2000,288(5472):1714-1715

Meteoriticists have long been puzzled by the fact that the most common meteorites, so-called ordinary chondrites, don't appear to have come from the most common asteroids, the S-types. Last week, however, a group of researchers attending the spring meeting of the American Geophysical Union here announced that the 31-kilometer-long S-type asteroid Eros now being orbited by the NEAR Shoemaker spacecraft is made of the same stuff as ordinary chondrites. That conclusion comes from NEAR Shoemaker's first-ever analysis of the elemental composition of an asteroid.  相似文献   

OCEANOGRAPHY: Missing Mixing Found in the Deep Sea     

Kerr RA 《Science (New York, N.Y.)》2000,288(5473):1947-1949

In their simulations of how the sea's ponderous flows of water and heat affect climate, including future greenhouse warming, climate modelers assumed that something evenly stirred the world ocean from top to bottom around the globe. But oceanographers gauging the tides of the world's seas from a satellite perch have found intense patches of tidally driven mixing deep within the open ocean. Once modelers include these patches, they should see some changes in model predictions of global warming.  相似文献   

OIL OUTLOOK:USGS Optimistic on World Oil Prospects     

Kerr RA 《Science (New York, N.Y.)》2000,289(5477):237

According to the latest estimates by the U.S. Geological Survey, the world has 20% more oil awaiting discovery in yet-to-be-found fields than the USGS estimated 6 years ago. And a newly analyzed category--oil lurking in and around known fields--offers almost as much additional oil as in those undiscovered reservoirs. But even if the additional oil is really there, pessimists argue that it pushes back the global production peak--and the end of the era of cheap oil--by years, not decades.  相似文献   

Sperm Morphology in the Domestic Cat, and its Relation with Fertility: A Retrospective Study     

E Axnér  C Linde Forsberg  Correction added after online publication April : from CL Forsberg to C Linde Forsberg 《Reproduction in domestic animals》2007,42(3):282-291

Knowledge about normal ranges in semen quality and the association between sperm morphology and fertility in felids is limited. The aims of this retrospective study were to (1) define a normal spermiogram in cats; (2) evaluate possible effects of season, age and breed on sperm morphology; and (3) evaluate the relationship between sperm morphology and fertility. Semen samples collected by electroejaculation from 52 cats were evaluated for sperm morphology. The cats constituted two groups: a general population of cats (n = 48) and cats examined because of poor breeding records (n = 4). The general population was divided into household (n = 20), pedigree (n = 19) and colony cats (n = 9) and into three age classes, <12 months, 12-59 months and >or=60 months. The median percentage of normal spermatozoa in the general population was 44.0% (range 1.0-91.0%). Criteria were tentatively set for what was considered a normal spermiogram. The mean percentage of normal spermatozoa was higher during February to July than during August to January (p < 0.05). Pedigree cats had a lower mean percentage of normal spermatozoa than did household cats (p < 0.05). Age had no effect on the percentage of normal spermatozoa but was positively correlated with the percentage of proximal droplets. Of the cats with <40% normal spermatozoa (n = 19), all those with known breeding records (n = 11) had produced litters. The four cats examined because of poor breeding results had higher percentages of different sperm abnormalities than tentatively stipulated for the normal spermiogram. In two of these cats both sperm morphology and fertility changed over time.  相似文献   

Stress and Parturition in the Pig*     

AB Lawrence  KA McLean  S Jarvis  CL Gilbert  JC Petherick 《Reproduction in domestic animals》1997,32(5):231-236

  相似文献   

Management of inappetant sheep during export by sea     

RT NORRIS  CL McDONALD  RB RICHARDS  MW HYDER  SP GITTINS  GJ NORMAN 《Australian veterinary journal》1990,67(7):244-247

In the first of 2 experiments, a simulated voyage was conducted to examine the effects of various treatments on bodyweight change and feeding frequency of inappetant sheep at the end of lot-feeding (non-feeders). The treatments, applied during simulated shipping, were: normal quantities of feed and length of troughs; extra trough length; extra feed. Adult Merino wethers (n = 108) were used in each treatment. A voyage to the Middle East was then conducted to establish whether shipboard mortality could be reduced by separating non-feeders (n = 305) from feeders (n = 5,620) late in the feedlot hase and housing the groups separately aboard ship. A control group of non-feeders (n = 215) mixed with feeders (n = 5,732) was used for comparison. Bars (marker bars), containing a coloured dye, were attached to feed troughs to mark sheep that fed. Most non-feeders (82%) began eating when placed in shipping pens in both studies. However, there was no significant difference in percentage of sheep that fed between non-feeders given extra trough length or extra feed compared with non-feeders given standard management at any stage of simulated shipping. There was no significant difference in mean bodyweights between treatment groups on days 1, 8 and 15 of simulated shipping. Differences in bodyweight on d 22 were probably associated with different levels of gut fill. Death rates were not significantly different in separated and control groups (1.1%, 0.9%, P = 0.6) in the voyage of 14 d to the Middle East.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献