Drilling to gabbro in intact ocean crust     

Wilson DS  Teagle DA  Alt JC  Banerjee NR  Umino S  Miyashita S  Acton GD  Anma R  Barr SR  Belghoul A  Carlut J  Christie DM  Coggon RM  Cooper KM  Cordier C  Crispini L  Durand SR  Einaudi F  Galli L  Gao Y  Geldmacher J  Gilbert LA  Hayman NW  Herrero-Bervera E  Hirano N  Holter S  Ingle S  Jiang S  Kalberkamp U  Kerneklian M  Koepke J  Laverne C  Vasquez HL  Maclennan J  Morgan S  Neo N  Nichols HJ  Park SH  Reichow MK  Sakuyama T  Sano T  Sandwell R  Scheibner B  Smith-Duque CE  Swift SA  Tartarotti P  Tikku AA  Tominaga M  Veloso EA 《Science (New York, N.Y.)》2006,312(5776):1016-1020

Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D.  相似文献   

Limited efficacy of an inactivated feline immunodeficiency virus vaccine     

Dunham SP  Bruce J  MacKay S  Golder M  Jarrett O  Neil JC 《The Veterinary record》2006,158(16):561-562

  相似文献   

Cytokine responses to EHV-1 infection in immune and non-immune ponies     

Coombs DK  Patton T  Kohler AK  Soboll G  Breathnach C  Townsend HG  Lunn DP 《Veterinary immunology and immunopathology》2006,111(1-2):109-116

Protecting equids against equine herpesvirus-1 (EHV-1) infection remains an elusive goal. Repeated infection with EHV-1 leads to protective immunity against clinical respiratory disease, and a study was conducted to measure the regulatory cytokine response (IFN-gamma and IL-4) in repeatedly infected immune ponies compared to non-immune ponies. Two groups of four ponies were established. Group 1 ponies had previously been infected on two occasions, and most recently 7 months before this study. Group 2 ponies had no history no vaccination or challenge infection prior to this study. Both groups were subjected to an intranasal challenge infection with EHV-1, and blood samples were collected pre-infection, and at 7 and 21 days post-infection for preparation of PBMCs. At each time point, the in vitro responses of PBMCs to stimulation with EHV-1 were measured, including IFN-gamma and IL-4 mRNA production, and lymphoproliferation. Group 1 ponies showed no signs of clinical disease or viral shedding after challenge infection. Group 2 ponies experienced a biphasic pyrexia, mucopurulent nasal discharge, and nasal shedding of virus after infection. Group 1 ponies had an immune response characterized both before and subsequent to challenge infection by an IFN-gamma response to EHV-1 in the absence of an IL-4 response, and demonstrated increased EHV-1-specific lymphoproliferation post-infection. Group 2 ponies had limited cytokine or lymphoproliferative responses to EHV-1 pre-challenge, and demonstrated increases in both IFN-gamma and IL-4 responses post-challenge, but without any lymphoproliferative response. Protective immunity to EHV-1 infection was therefore characterized by a polarized IFN-gamma dependent immunoregulatory cytokine response.  相似文献   

Immune responses to commercial equine vaccines against equine herpesvirus-1, equine influenza virus, eastern equine encephalomyelitis, and tetanus     

Holmes MA  Townsend HG  Kohler AK  Hussey S  Breathnach C  Barnett C  Holland R  Lunn DP 《Veterinary immunology and immunopathology》2006,111(1-2):67-80

Horses are commonly vaccinated to protect against pathogens which are responsible for diseases which are endemic within the general horse population, such as equine influenza virus (EIV) and equine herpesvirus-1 (EHV-1), and against a variety of diseases which are less common but which lead to greater morbidity and mortality, such as eastern equine encephalomyelitis virus (EEE) and tetanus. This study consisted of two trials which investigated the antigenicity of commercially available vaccines licensed in the USA to protect against EIV, EHV-1 respiratory disease, EHV-1 abortion, EEE and tetanus in horses. Trial I was conducted to compare serological responses to vaccines produced by three manufacturers against EIV, EHV-1 (respiratory disease), EEE, and tetanus given as multivalent preparations or as multiple vaccine courses. Trial II compared vaccines from two manufacturers licensed to protect against EHV-1 abortion, and measured EHV-1-specific interferon-gamma (IFN-gamma) mRNA production in addition to serological evidence of antigenicity. In Trial I significant differences were found between the antigenicity of different commercial vaccines that should be considered in product selection. It was difficult to identify vaccines that generate significant immune responses to respiratory viruses. The most dramatic differences in vaccine performance occurred in the case of the tetanus antigen. In Trial II both vaccines generated significant antibody responses and showed evidence of EHV-1-specific IFN-gamma mRNA responses. Overall there were wide variations in vaccine response, and the vaccines with the best responses were not produced by a single manufacturer. Differences in vaccine performance may have resulted from differences in antigen load and adjuvant formulation.  相似文献   

Expression of TECK/CCL25 and MEC/CCL28 chemokines and their respective receptors CCR9 and CCR10 in porcine mucosal tissues   总被引：8，自引：0，他引：8  

Meurens F  Berri M  Whale J  Dybvig T  Strom S  Thompson D  Brownlie R  Townsend HG  Salmon H  Gerdts V 《Veterinary immunology and immunopathology》2006,113(3-4):313-327

  相似文献   

Formulation with CpG ODN enhances antibody responses to an equine influenza virus vaccine   总被引：3，自引：0，他引：3  

Lopez AM  Hecker R  Mutwiri G  van Drunen Littel-van den Hurk S  Babiuk LA  Townsend HG 《Veterinary immunology and immunopathology》2006,114(1-2):103-110

Previous studies have shown that protection against equine influenza virus (EIV) is partially mediated by virus-specific IgGa and IgGb. In this study we tested whether addition of a CpG ODN formulation to a commercial killed virus vaccine would enhance EIV-specific IgGa and IgGb antibody responses, and improve protection against an experimental EIV challenge. Thirty na?ve horses were assigned to one of three groups and vaccinated as follows: 10 were given vaccine (Encevac TC4, Intervet Inc.) alone, 10 were given vaccine plus 0.25 mg CpG ODN 2007 formulated with 30% Emulsigen (CpG/Em), and 10 controls were given saline. All horses were challenged with live virus 12 weeks after the final vaccination. Antibody responses were tested by single radial hemolysis (SRH) and ELISA, and protection was evaluated by determination of temperature, coughing, and clinical scores. Killed virus vaccine combined with CpG/Em induced significantly greater serologic responses than did the vaccine alone. All antibody isotypes tested increased after the addition of CpG/Em, although no shift in relative antibody isotypes concentrations was detected. Vaccination significantly improved protection against challenge but the differences between the two vaccine groups were not statistically significant. This study is the first demonstration that CpG/Em enhances antigen-specific antibody responses in horses and supports its potential to be used as an adjuvant for vaccines against equine infections.  相似文献   

Objective measurement of pruritus in dogs: a preliminary study using activity monitors     

Nuttall T  McEwan N 《Veterinary dermatology》2006,17(5):348-351

Pruritus is an important clinical sign and quality-of-life measure in canine dermatology, but can be difficult to assess objectively. Several studies in humans have used activity monitors to measure nocturnal scratching in patients with atopic dermatitis. The results correlate with observation of scratching, scoring in atopic dermatitis indices and levels of inflammatory chemokines. The aim of this study was to examine whether an activity monitor could be used to detect elevated interexercise (i.e. 'resting') activity in atopic dogs compared to healthy dogs. Five healthy dogs and six dogs with atopic dermatitis were fitted with a collar-mounted activity monitor (Actiwatch) that recorded the piezo-electric voltage generated over 15-s epochs for 7 days. Data from defined periods of exercise, playing, etc., were disregarded. Within each group, median (+/- interquartile range) epoch activity was similar during the day (atopic 21.0 [9.8-24.8]; healthy 5.1 [4.6-6.0]) and evening (atopic 19.1 [10.9-25.2]; healthy 5.8 [5.3-11.7]), and significantly lower overnight (atopic 5.8 [4.1-15.7]; healthy 2.5 [1.6-4.4]) (Mann-Whitney test; P < 0.05). The mean epoch activity, however, was significantly higher in atopic dogs compared to healthy dogs for all three time periods (P < 0.05). This study provides preliminary evidence that activity monitors could objectively assess canine pruritus in the normal home environment.  相似文献   

Thrice out of Africa: ancient and recent expansions of the honey bee, Apis mellifera   总被引：1，自引：0，他引：1  

Whitfield CW  Behura SK  Berlocher SH  Clark AG  Johnston JS  Sheppard WS  Smith DR  Suarez AV  Weaver D  Tsutsui ND 《Science (New York, N.Y.)》2006,314(5799):642-645

We characterized Apis mellifera in both native and introduced ranges using 1136 single-nucleotide polymorphisms genotyped in 341 individuals. Our results indicate that A. mellifera originated in Africa and expanded into Eurasia at least twice, resulting in populations in eastern and western Europe that are geographically close but genetically distant. A third expansion in the New World has involved the near-replacement of previously introduced "European" honey bees by descendants of more recently introduced A. m. scutellata ("African" or "killer" bees). Our analyses of spatial transects and temporal series in the New World revealed differential replacement of alleles derived from eastern versus western Europe, with admixture evident in all individuals.  相似文献   

Genetic analysis and genotype × environment (G × E) for grey leaf spot disease resistance in elite African maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) germplasm     

Julia Sibiya  Pangirayi Tongoona  John Derera  Neil van Rij 《Euphytica》2012,185(3):349-362

Maize grey leaf spot (GLS) disease remains an important foliar disease in sub-Saharan Africa accounting for more than 25% yield losses in maize. Information on inheritance of GLS resistance of germplasm adapted to African environments is required in new sources being identified. Therefore, hybrids generated from a 10 × 10 half-diallel mating of tropical advanced maize inbred lines were evaluated in six environments to determine combining ability, genotype × environment interaction (G × E) and the impact of GLS disease on grain yield. General combining ability effects were highly significant and accounted for 72 and 68% of the variation for GLS resistance and grain yield, respectively. Significant specific combining ability effects associated with reduced disease levels were observed in some hybrids when one parent was resistant, and these may be exploited in developing single cross maize hybrids. Regression analysis showed a 260–320 kg ha^?1 decrease in maize grain yield per each increase in GLS disease severity score, and significant associations (r = ?0.31 to ?0.60) were observed between grain yield and GLS severity scores. This showed the potential of GLS disease to reduce yield in susceptible varieties grown under favourable disease conditions, without control measures. Genotype and genotype × environment biplots and correlation analysis indicated that the significant G × E observed was not due to changes in hybrid ranking, implying absence of a significant crossover interaction. Therefore, predominance of additive gene effects imply that breeding progress for GLS disease resistance would be made through selection and this could be achieved at a few hot-spot sites, such as Baynesfield and Cedara locations in South Africa, and still deploy the resistant germplasm to other environments in which they are adapted.  相似文献   

Neural representations of location composed of spatially periodic bands     

J Krupic  N Burgess  J O'Keefe 《Science (New York, N.Y.)》2012,337(6096):853-857

The mammalian hippocampal formation provides neuronal representations of environmental location, but the underlying mechanisms are poorly understood. Here, we report a class of cells whose spatially periodic firing patterns are composed of plane waves (or bands) drawn from a discrete set of orientations and wavelengths. The majority of cells recorded in parasubicular and medial entorhinal cortices of freely moving rats belonged to this class and included grid cells, an important subset that corresponds to three bands at 60° orientations and has the most stable firing pattern. Occasional changes between hexagonal and nonhexagonal patterns imply a common underlying mechanism. Our results indicate a Fourier-like spatial analysis underlying neuronal representations of location, and suggest that path integration is performed by integrating displacement along a restricted set of directions.  相似文献