A long-snouted predatory dinosaur from africa and the evolution of spinosaurids     

PC Sereno  AL Beck  DB Dutheil  B Gado  HCE Larsson  GH Lyon  JD Marcot  OWM Rauhut  RW Sadleir  CA Sidor  DD Varricchio  GP Wilson  JA Wilson 《Science (New York, N.Y.)》1998,282(5392):1298-1302

Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous.  相似文献   

Unconditional quantum teleportation   总被引：5，自引：0，他引：5  

A Furusawa  JL Sorensen  SL Braunstein  CA Fuchs  HJ Kimble  ES Polzik 《Science (New York, N.Y.)》1998,282(5389):706-709

Quantum teleportation of optical coherent states was demonstrated experimentally using squeezed-state entanglement. The quantum nature of the achieved teleportation was verified by the experimentally determined fidelity Fexp = 0.58 +/- 0.02, which describes the match between input and output states. A fidelity greater than 0.5 is not possible for coherent states without the use of entanglement. This is the first realization of unconditional quantum teleportation where every state entering the device is actually teleported.  相似文献   

Thermodynamics of calcite growth: baseline for understanding biomineral formation     

HH Teng  PM Dove  CA Orme  De Yoreo JJ 《Science (New York, N.Y.)》1998,282(5389):724-727

The complexity of biomineralized structures suggests the potential of organic constituents for controlling energetic factors during crystal synthesis. Atomic force microscopy was used to investigate the thermodynamic controls on carbonate growth and to measure the dependence of step speed on step length and the dependence of critical step length on supersaturation in precisely controlled solutions. These data were used to test the classic Gibbs-Thomson relationship and provided the step edge free energies and free energy barriers to one-dimension nucleation for calcite. Addition of aspartic acid, a common component in biomineralizing systems, dramatically affected growth morphology and altered the magnitude of the surface energy.  相似文献   

Vitamin D3 supplementation of beef steers increases longissimus tenderness.   总被引：11，自引：0，他引：11  

S S Swanek  J B Morgan  F N Owens  D R Gill  C A Strasia  H G Dolezal  F K Ray 《Journal of animal science》1999,77(4):874-881

The objectives of these experiments were to determine 1) the effectiveness of supplemental vitamin D3 (VITD) on altering plasma and muscle calcium levels, 2) whether VITD supplementation improves Warner-Bratzler shear force (WBS) values of steaks from feedlot beef steers, and 3) the tenderness response curve of longissimus steaks from steers supplemented with VITD. In Exp. 1, 20 crossbred steers were assigned randomly to one of four treatment diets consisting of either 0, 2.5, 5.0, or 7.5 x 106 IU of VITD per day for 10 d. Blood samples were obtained daily during this supplementation period and 5 d thereafter (d 11 to 15). Between d 6 and 13, a linear increase (P < .01) in ionized plasma calcium concentrations was observed in steers supplemented with VITD. Compared to unsupplemented steers, serum calcium concentrations of the steers receiving 7.5 x 106 IU of VITD per day were increased 8 to 48%. In Exp. 2, longissimus samples from crossbred steers (n = 118) that were supplemented with either 0 or 5 x 106 IU of VITD per day for 7 d were obtained and aged for 7, 14, or 21 d. Following the initial 7-d postmortem aging period, VITD supplementation lowered (P < .01) WBS (.58 kg) and increased sensory tenderness rating (.6 units) compared to cuts originating from unsupplemented steers. In Exp. 3, 44 steers were supplemented with either 0 or 7.5 x 106 IU of VITD per day for 10 d immediately prior to slaughter. Results indicated that plasma and longissimus calcium concentration were higher (P < .05) for steers that received supplemental VITD. Compared with unsupplemented cuts, VITD supplementation improved WBS of cuts aged for either 7 or 14 d (P = .02 and P = .07, respectively). Sensory panelists rated samples from VITD supplemented steers as more tender than their unsupplemented counterparts. Activation of calpain proteases could be responsible for the observed tenderization due to the supplementation of VITD.  相似文献   

Book Reviews     

Gill Simpson 《The Journal of small animal practice》1999,40(9):452-452

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Ecology of Aquatic Systems     

Andrew B. Gill 《Fish and Fisheries》2011,12(3):352-352

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Reduced translocation in 2,4‐D‐resistant oriental mustard populations (Sisymbrium orientale L.) from Australia          下载免费PDF全文

Hue Thi Dang  Jenna M Malone  Peter Boutsalis  Mahima Krishnan  Gurjeet Gill  Christopher Preston 《Pest management science》2018,74(6):1524-1532

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Camera traps and activity signs to estimate wild boar density and derive abundance indices          下载免费PDF全文

Giovanna Massei  Julia Coats  Mark Simon Lambert  Stephane Pietravalle  Robin Gill  Dave Cowan 《Pest management science》2018,74(4):853-860

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Tetraoxanes as a new class of efficient herbicides comparable with commercial products          下载免费PDF全文

Raphael C Cusati  Luiz CA Barbosa  Célia RA Maltha  Antônio J Demuner  Alberto Oliveros‐Bastidas  Antônio A Silva 《Pest management science》2015,71(7):1037-1048

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Factors impacting blackleg development caused by Dickeya spp. in the field     

Elena Dubois Gill  Santiago Schaerer  Brice Dupuis 《European journal of plant pathology / European Foundation for Plant Pathology》2014,140(2):317-327

Stem rot symptoms caused by pectinolytic bacteria of Genus Pectobacterium and Genus Dickeya, which are commonly referred to as blackleg, strongly impact the quality of seed potato production in most European countries. Several biotic and abiotic factors, such as cultivar susceptibility, isolate aggressiveness, mother tuber infection density and a wide range of soil-related and climatic factors have been identified in the literature as having an effect on blackleg development. The aim of this study was to identify which biotic and/or abiotic factors are most critical to the development of blackleg in the field. In Switzerland, the predominant species have belonged to Genus Dickeya as far back as 1992, which is why this study only investigates blackleg symptoms induced by Dickeya isolates. Seven field trials, in which inoculated tubers were planted, were conducted during a 3-year period and the number of blackleg-diseased plants was counted. Multiple regression analysis was used in order to determine the factors that had the greatest impact on two different variables: (i) periods between emergence of the plant and disease outbreak and (ii) overall blackleg incidence throughout the growing season. The results of this analysis have revealed that environmental factors, such as evapotranspiration and soil moisture, explain about half of the variability in the number of days before disease outbreak, and the total number of diseased plants is widely dependent upon cultivar susceptibility and isolate aggressiveness.  相似文献