Perirenal hemorrhage syndrome in market turkey toms: effect of management factors

Differences in the overall mortality rates and mortality due to perirenal hemorrhage syndrome (PHS) were compared in large white Nicholas tom turkeys. The study evaluated the effects of 1) four different light and temperature treatments; 2) three feed additives proposed to have anti-stress effects (reserpine, acetylsalicylic acid, and increased calcium); 3) toe-clipping on mortality, various disease conditions, and production parameters. Mortality varied from 0.60% to 3.57% among groups. Increased room temperature (21 C), toe-clipping, step-up/step-down lighting, and dietary reserpine reduced the incidence of PHS as compared with lower room temperature (13 C), no toe-clipping, intermittent lighting (2 hours light, 4 hours dark), and no dietary reserpine. Dietary aspirin or elevated calcium levels had no effect on PHS incidence. Overall mortality was greatest in the warmer rooms.     

Composition of saturnian stream particles

During Cassini's approach to Saturn, the Cosmic Dust Analyser (CDA) discovered streams of tiny (less than 20 nanometers) high-velocity (approximately 100 kilometers per second) dust particles escaping from the saturnian system. A fraction of these impactors originated from the outskirts of Saturn's dense A ring. The CDA time-of-flight mass spectrometer recorded 584 mass spectra from the stream particles. The particles consist predominantly of oxygen, silicon, and iron, with some evidence of water ice, ammonium, and perhaps carbon. The stream particles primarily consist of silicate materials, and this implies that the particles are impurities from the icy ring material rather than the ice particles themselves.     

Samples of stars beyond the solar system: silicate grains in interplanetary dust

We have identified six circumstellar silicate grains within interplanetary dust particles (IDPs). Their extrasolar origins are demonstrated by their extremely anomalous oxygen isotopic compositions. Three 17O-rich grains appear to originate from red giant or asymptotic giant branch stars. One 16O-rich grain may be from a metal-poor star. Two 16O-poor grains have unknown stellar sources. One of the grains is forsterite, and two are amorphous silicate "GEMS" (glass with embedded metal and sulfides), which is consistent with astronomical identifications of crystalline and amorphous silicates in the outflows of evolved stars. These observations suggest cometary origins of these IDPs and underscore the perplexing absence of silicates among circumstellar dust grains from meteorites.     

用Glu-B3、Gli-B1和SEC-1b复合引物PCR检测普通小麦1BL/1RS易位系

 利用低分子量 (LMW )麦谷蛋白Glu B3的STS PCR标记、醇溶蛋白Gli B1的SSR标记和黑麦碱SEC 1b的STS PCR标记的复合PCR ,对 10个普通小麦品种、中优 950 7/CA963 2的 91个DH系和 2 8个F2 个体植株 ,进行了1BL/1RS易位系的检测。结果表明 ,中优 950 7/CA963 2的 3 9个DH系和CA963 2、晋麦 45、兰考 2 4、烟农 18、京冬 8等5个品种缺失 2个小麦贮藏蛋白位点的PCR产物 ,而拥有黑麦碱的PCR产物。利用PAGE和ELISA方法 ,对上述品种 (系 )进行了黑麦碱 (secalin)蛋白的检测 ,发现这些品种 (系 )均包含secalin ,与分子标记的检测结果吻合 ,是 1BL/1RS易位系。对 2 8个F2 单株的检测表明 ,该复合标记可以检测出早代 1BL/1RS的纯合和杂合植株     

Bovine viral diarrhea virus: An updated American College of Veterinary Internal Medicine consensus statement with focus on virus biology,hosts, immunosuppression,and vaccination

Control of bovine viral diarrhea virus (BVDV) in cattle populations across most of the world has remained elusive in spite of advances in knowledge about this viral pathogen. A central feature of virus perseverance in cattle herds is the unique mechanism of persistent infection. Managing BVDV infection in herds involves controlling persistently infected carrier animals using a multidimensional approach of vaccination, biosecurity, and identification of BVDV reservoirs. A decade has passed since the original American College of Veterinary Internal Medicine consensus statement on BVDV. While much has remained the same with respect to clinical signs of disease, pathogenesis of infection including persistent infection, and diagnosis, scientific articles published since 2010 have led to a greater understanding of difficulties associated with control of BVDV. This consensus statement update on BVDV presents greater focus on topics currently relevant to the biology and control of this viral pathogen of cattle, including changes in virus subpopulations, infection in heterologous hosts, immunosuppression, and vaccination.     

Comment on "Global trends in wind speed and wave height"

Young et al. (Reports, 22 April 2011, p. 451) reported trends in global mean wind speed much larger than found by other investigators. Their report fails to reference these other investigations and does not discuss the consequences that such large wind trends would have on global evaporation and precipitation. The difference between their altimeter and buoy trends suggests a relatively large trend error.     

Laser altimeter observations from MESSENGER's first Mercury flyby

A 3200-kilometers-long profile of Mercury by the Mercury Laser Altimeter on the MESSENGER spacecraft spans approximately 20% of the near-equatorial region of the planet. Topography along the profile is characterized by a 5.2-kilometer dynamic range and 930-meter root-mean-square roughness. At long wavelengths, topography slopes eastward by 0.02 degrees , implying a variation of equatorial shape that is at least partially compensated. Sampled craters on Mercury are shallower than their counterparts on the Moon, at least in part the result of Mercury's higher gravity. Crater floors vary in roughness and slope, implying complex modification over a range of length scales.     

Structural mutations of the T cell receptor zeta chain and its role in T cell activation

T cell hybridomas that express zeta zeta, but not zeta eta, dimers in their T cell receptors (TCRs) produce interleukin-2 (IL-2) and undergo an inhibition of spontaneous growth when activated by antigen, antibodies to the receptor, or antibodies to Thy-1. Hybridomas without zeta and eta were reconstituted with mutated zeta chains. Cytoplasmic truncations of up to 40% of the zeta molecule reconstituted normal surface assembly of TCRs, but antigen-induced IL-2 secretion and growth inhibition were lost. In contrast, cross-linking antibodies to the TCR activated these cells. A point mutation conferred the same signaling phenotype as did the truncations and caused defective antigen-induced tyrosine kinase activation. Thus zeta allows the binding of antigen/major histocompatibility complex (MHC) to alpha beta to effect TCR signaling.