Chick's response to an imprinting stimulus: heterosis and evolution     

H B Graves  P B Siegel 《Science (New York, N.Y.)》1968,160(825):329-330

Tendencies of day-old chicks to respond toward, to approach, and to stay near a distant audiovisulal imprinting apparatus were shown to be inherited in a heterotic manner. High correlations found among the traits suggest that these behavioral responses are not independent but sequential. The fitness value of such a behavioral sequence is explained in terms of imprinting.  相似文献   

Carbon dioxide fixation by mouse embryos prior to implantation   总被引：1，自引：0，他引：1  

C N Graves  J D Biggers 《Science (New York, N.Y.)》1970,167(924):1506-1508

Mouse embryos in the stage of development prior to implantation were cultured in vitro in a medium that contained radioactive bicarbonate. The radioactivity was incorporated into the proteins and nucleic acids that were acid soluble. Uptake of radioactivity occurred into protein in the unfertilized ovum and was highest in all fractions in the early blastocyst stage. No incorporation was detected in the lipid fraction.  相似文献   

Bulk Spin-Resonance Quantum Computation   总被引：6，自引：0，他引：6  

NA Gershenfeld  IL Chuang 《Science (New York, N.Y.)》1997,275(5298):350-356

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The insulin receptor contains a calmodulin-binding domain   总被引：3，自引：0，他引：3  

C B Graves  R R Goewert  J M McDonald 《Science (New York, N.Y.)》1985,230(4727):827-829

Substantial evidence suggests that calcium has a pivotal role in regulating the initial events through which insulin alters plasma membrane metabolism. Because binding of insulin to its receptor represents the initial site of insulin action in the plasma membrane, studies were undertaken to determine whether the insulin receptor is a calmodulin-binding protein. Preparations enriched in the insulin receptor and calmodulin-binding proteins were isolated from detergent-solubilized rat adipocyte membranes by chromatography with wheat germ agglutinin agarose and calmodulin-conjugated Sepharose, respectively. Substantial purification of a manganese-dependent, insulin-sensitive phosphoprotein of 95K identified as the beta subunit of the insulin receptor was accomplished. Binding and photocovalent cross-linking of iodine-125-labeled calmodulin to these affinity-purified preparations and to isolated plasma membranes, followed by immunoadsorption with insulin receptor antibodies bound to protein A Sepharose, resulted in significant purification of a binding complex of 110K to 140K. These results indicate that the adipocyte insulin receptor or a polypeptide closely associated with the receptor is a calmodulin-binding protein.  相似文献   

OBITUARY     

Graves HS 《Science (New York, N.Y.)》1932,75(1953):575-577

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Two leguminous tree species differ in growth and ion uptake in Hoagland solution: Phosphorus toxicity in Amur Maackia 1     

Anthony S. Aiello  William R. Graves 《Journal of plant nutrition》2013,36(7):1061-1073

Hydroponic culture of tree seedlings is used commonly to study root biology; however, we have found that two species of woody legumes differ in their responses to this practice. Seedlings of Amur maackia (Maackia amurensis Rupr. & Maxim.) and black locust (Robinia pseudoacacia L.) were cultured in 1, 5, 10, 25, 50, and 100% Hoagland solution #1 for 5 weeks. Total dry mass of black locust increased with increasing solution concentration up to 50%. Amur maackia dry mass was greatest in 5% solution. Bronzing, chlorosis, and necrosis occurred on leaves of Amur maackia in solutions 10%, and symptom severity increased with solution strength. Leaf phosphorus (P) content of Amur maackia increased from 0.40 to 1.95% of dry mass as solution strength increased from 5 to 50%. Amur maackia grown in a soil‐based medium and irrigated with 50% solution showed no foliar toxicity symptoms, and P content of the leaves of these plants was 0.279%. Laminae of Amur maackia had higher manganese (Mn) content than laminae of black locust at solution concentrations above 5%. Levels of calcium (Ca) and magnesium (Mg) in laminae of Amur maackia suggest an enhanced ability of this species to absorb ions from its medium. Results indicate no elemental deficiencies for either species. We conclude that black locust can be grown hydroponically using standard methods. However, growth of Amur maackia in solution is inhibited at concentrations of Hoagland solution #1 >10%, suggesting a sensitivity to the availability of ions and perhaps an enhanced ability to sequester ions from its medium.  相似文献   

Behaviour and cleanliness of replacement dairy heifers housed in group pens with combined feeding–resting stalls     

K. E. Bøe  G. Færevik  R. E. Graves 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):17-22

Abstract

This study was carried out in two commercial Norwegian dairy herds where the replacement heifers were kept in groups of 10 in pens with 6 conventional free-stalls and 5 combined stalls at the feed bunk. The stall cleanliness was better in the free-stalls than in the combined stalls (P?<?.01). Time spent lying was not affected by number of animals in the group (P?=?.20), but feeding synchrony (P?=?.05) and lying synchrony (<.001) were higher when there were six animals in the group. The heifers showed a clear preference for lying in the standard free-stalls and this was not affected by number of animals in the pen (P?=?.83). The results of this initial study indicate that a pen system with combined lying/feeding stalls and free-stalls offers a satisfactory lying comfort, apparently minimal competition over lying space and acceptable animal cleanliness.  相似文献   

Evaluation of canine antimicrobial peptides in infected and noninfected chronic atopic skin     

Domenico Santoro  David Bunick  Thomas K. Graves  Mariangela Segre 《Veterinary dermatology》2013,24(1):39-e10

Background – Antimicrobial peptides (AMPs) are small immunomodulatory peptides produced by epithelial and immune cells. β‐Defensins (BDs) and cathelicidins (Caths) are the most studied AMPs. Recently, increased cutaneous expression of AMPs was reported in atopic humans and in beagles with experimentally induced atopy. Hypothesis/Objectives – Our goal was to analyse mRNA expression and protein levels of canine (c)BD1‐like, cBD2‐like/122, cBD3‐like, cBD103 and cCath in healthy and naturally affected atopic dogs, with and without active skin infection, along with their distribution in the epidermis using indirect immunofluorescence. Animals – Skin biopsies were taken from 14 healthy and 11 atopic privately owned dogs. Methods – The mRNA levels of cBD1‐like, cBD2‐like/122, cBD3‐like, cBD103 and cCath were quantified using quantitative real‐time PCR. The protein levels of cBD3‐like and cCath were analysed by relative competitive inhibition enzyme‐linked immunosorbent assay, while the distributions of cBD2‐like/122, cBD3‐like and cCath were detected by indirect immunofluorescence. Results – Dogs with atopic dermatitis had significantly greater mRNA expression of cBD103 (P = 0.04) than control dogs. Furthermore, atopic skin with active infection had a higher cBD103 mRNA expression (P = 0.01) and a lower cBD1‐like mRNA expression (P = 0.04) than atopic skin without infection. No significant differences in protein levels (cBD3‐like and cCath) or epidermal distribution of AMPs (cBD2‐like/122, cBD3‐like and cCath) were seen between healthy and atopic dogs. Conclusions and clinical importance – Expression of cBD103 mRNA was greater, while expression of cBD1‐like mRNA was lower in dogs with atopic dermatitis that had active infections. Work is needed to clarify the biological mechanisms and possible therapeutic options to maintain a healthy canine skin.  相似文献   

The influence of landscape characteristics and home-range size on the quantification of landscape-genetics relationships   总被引：1，自引：1，他引：0  

Tabitha A. Graves  Tzeidle N. Wasserman  Milton Cezar Ribeiro  Erin L. Landguth  Stephen F. Spear  Niko Balkenhol  Colleen B. Higgins  Marie-Josée Fortin  Samuel A. Cushman  Lisette P. Waits 《Landscape Ecology》2012,27(2):253-266

A common approach used to estimate landscape resistance involves comparing correlations of ecological and genetic distances calculated among individuals of a species. However, the location of sampled individuals may contain some degree of spatial uncertainty due to the natural variation of animals moving through their home range or measurement error in plant or animal locations. In this study, we evaluate the ways that spatial uncertainty, landscape characteristics, and genetic stochasticity interact to influence the strength and variability of conclusions about landscape-genetics relationships. We used a neutral landscape model to generate 45 landscapes composed of habitat and non-habitat, varying in percent habitat, aggregation, and structural connectivity (patch cohesion). We created true and alternate locations for 500 individuals, calculated ecological distances (least-cost paths), and simulated genetic distances among individuals. We compared correlations between ecological distances for true and alternate locations. We then simulated genotypes at 15 neutral loci and investigated whether the same influences could be detected in simple Mantel tests and while controlling for the effects of isolation-by-distance using the partial Mantel test. Spatial uncertainty interacted with the percentage of habitat in the landscape, but led to only small reductions in correlations. Furthermore, the strongest correlations occurred with low percent habitat, high aggregation, and low to intermediate levels of cohesion. Overall genetic stochasticity was relatively low and was influenced by landscape characteristics.  相似文献   

How is agroforestry perceived in Europe? An assessment of positive and negative aspects by stakeholders     

Silvestre García de Jalón  Paul J. Burgess  Anil Graves  Gerardo Moreno  Jim McAdam  Eric Pottier  Sandra Novak  Valerio Bondesan  Rosa Mosquera-Losada  Josep Crous-Durán  Joao H. N. Palma  Joana A. Paulo  Tania S. Oliveira  Eric Cirou  Yousri Hannachi  Anastasia Pantera  Régis Wartelle  Sonja Kay  Nina Malignier  Philippe Van Lerberghe  Penka Tsonkova  Jaconette Mirck  Mercedes Rois  Anne Grete Kongsted  Claudine Thenail  Boki Luske  Staffan Berg  Marie Gosme  Andrea Vityi 《Agroforestry Systems》2018,92(4):829-848

Whilst the benefits of agroforestry are widely recognised in tropical latitudes few studies have assessed how agroforestry is perceived in temperate latitudes. This study evaluates how stakeholders and key actors including farmers, landowners, agricultural advisors, researchers and environmentalists perceive the implementation and expansion of agroforestry in Europe. Meetings were held with 30 stakeholder groups covering different agroforestry systems in 2014 in eleven EU countries (Denmark, France, Germany, Greece, Hungary, Italy, Netherlands, Portugal, Spain, Sweden and the United Kingdom). In total 344 valid responses were received to a questionnaire where stakeholders were asked to rank the positive and negative aspects of implementing agroforestry in their region. Improved biodiversity and wildlife habitats, animal health and welfare, and landscape aesthetics were seen as the main positive aspects of agroforestry. By contrast, increased labour, complexity of work, management costs and administrative burden were seen as the most important negative aspects. Overall, improving the environmental value of agriculture was seen as the main benefit of agroforestry, whilst management and socio-economic issues were seen as the greatest barriers. The great variability in the opportunities and barriers of the systems suggests enhanced adoption of agroforestry across Europe will be most likely to occur with specific initiatives for each type of system.  相似文献