Hooke and generation of molds     

Lazcano A 《Science (New York, N.Y.)》2003,301(5641):1845

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A neutralizing antibody selected from plasma cells that binds to group 1 and group 2 influenza A hemagglutinins   总被引：2，自引：0，他引：2  

Corti D  Voss J  Gamblin SJ  Codoni G  Macagno A  Jarrossay D  Vachieri SG  Pinna D  Minola A  Vanzetta F  Silacci C  Fernandez-Rodriguez BM  Agatic G  Bianchi S  Giacchetto-Sasselli I  Calder L  Sallusto F  Collins P  Haire LF  Temperton N  Langedijk JP  Skehel JJ  Lanzavecchia A 《Science (New York, N.Y.)》2011,333(6044):850-856

The isolation of broadly neutralizing antibodies against influenza A viruses has been a long-sought goal for therapeutic approaches and vaccine design. Using a single-cell culture method for screening large numbers of human plasma cells, we isolated a neutralizing monoclonal antibody that recognized the hemagglutinin (HA) glycoprotein of all 16 subtypes and neutralized both group 1 and group 2 influenza A viruses. Passive transfer of this antibody conferred protection to mice and ferrets. Complexes with HAs from the group 1 H1 and the group 2 H3 subtypes analyzed by x-ray crystallography showed that the antibody bound to a conserved epitope in the F subdomain. This antibody may be used for passive protection and to inform vaccine design because of its broad specificity and neutralization potency.  相似文献   

Ultrahigh-density nanowire lattices and circuits     

Melosh NA  Boukai A  Diana F  Gerardot B  Badolato A  Petroff PM  Heath JR 《Science (New York, N.Y.)》2003,300(5616):112-115

We describe a general method for producing ultrahigh-density arrays of aligned metal and semiconductor nanowires and nanowire circuits. The technique is based on translating thin film growth thickness control into planar wire arrays. Nanowires were fabricated with diameters and pitches (center-to-center distances) as small as 8 nanometers and 16 nanometers, respectively. The nanowires have high aspect ratios (up to 10(6)), and the process can be carried out multiple times to produce simple circuits of crossed nanowires with a nanowire junction density in excess of 10(11) per square centimeter. The nanowires can also be used in nanomechanical devices; a high-frequency nanomechanical resonator is demonstrated.  相似文献   

Polymer gate dielectric surface viscoelasticity modulates pentacene transistor performance     

Kim C  Facchetti A  Marks TJ 《Science (New York, N.Y.)》2007,318(5847):76-80

Nanoscopically confined polymer films are known to exhibit substantially depressed glass transition temperatures (Lg's) as compared to the corresponding bulk materials. We report here that pentacene thin films grown on polymer gate dielectrics at temperatures well below their bulk Tg's exhibit distinctive and abrupt morphological and microstructural transitions and thin-film transistor (TFT) performance discontinuities at well-defined growth temperatures. The changes reflect the higher chain mobility of the dielectric in its rubbery state and are independent of dielectric film thickness. Optimization of organic TFT performance must recognize this fundamental buried interface viscoelasticity effect, which is detectable in the current-voltage response.  相似文献   

Extracellular DNA plays a key role in deep-sea ecosystem functioning   总被引：1，自引：0，他引：1  

Dell'Anno A  Danovaro R 《Science (New York, N.Y.)》2005,309(5744):2179

The ecological role and biogeochemical relevance of extracellular DNA in the oceanic sediments are unknown. Our global estimates indicate that up to 0.45 gigatons of extracellular DNA are present in the top 10 centimeters of deep-sea sediments, representing the largest reservoir of DNA in the world oceans. We demonstrate that extracellular DNA accounts for about one fifth of the total organic phosphorus regeneration and provides almost half of the prokaryotic demand for organic phosphorus. It therefore plays a key role in deep-sea ecosystem functioning on a global scale.  相似文献   

The Miller volcanic spark discharge experiment     

Johnson AP  Cleaves HJ  Dworkin JP  Glavin DP  Lazcano A  Bada JL 《Science (New York, N.Y.)》2008,322(5900):404

Miller's 1950s experiments used, besides the apparatus known in textbooks, one that generated a hot water mist in the spark flask, simulating a water vapor-rich volcanic eruption. We found the original extracts of this experiment in Miller's material and reanalyzed them. The volcanic apparatus produced a wider variety of amino acids than the classic one. Release of reduced gases in volcanic eruptions accompanied by lightning could have been common on the early Earth. Prebiotic compounds synthesized in these environments could have locally accumulated, where they could have undergone further processing.  相似文献   

Functional links between Aβ toxicity, endocytic trafficking, and Alzheimer's disease risk factors in yeast     

Treusch S  Hamamichi S  Goodman JL  Matlack KE  Chung CY  Baru V  Shulman JM  Parrado A  Bevis BJ  Valastyan JS  Han H  Lindhagen-Persson M  Reiman EM  Evans DA  Bennett DA  Olofsson A  DeJager PL  Tanzi RE  Caldwell KA  Caldwell GA  Lindquist S 《Science (New York, N.Y.)》2011,334(6060):1241-1245

Aβ (beta-amyloid peptide) is an important contributor to Alzheimer's disease (AD). We modeled Aβ toxicity in yeast by directing the peptide to the secretory pathway. A genome-wide screen for toxicity modifiers identified the yeast homolog of phosphatidylinositol binding clathrin assembly protein (PICALM) and other endocytic factors connected to AD whose relationship to Aβ was previously unknown. The factors identified in yeast modified Aβ toxicity in glutamatergic neurons of Caenorhabditis elegans and in primary rat cortical neurons. In yeast, Aβ impaired the endocytic trafficking of a plasma membrane receptor, which was ameliorated by endocytic pathway factors identified in the yeast screen. Thus, links between Aβ, endocytosis, and human AD risk factors can be ascertained with yeast as a model system.  相似文献   

Characterization of lettuce (Lactuca sativa L.) grown with biopesticides and deltamethrin     

Simone Palma Favaro  Yardlei Carlos AlbaAnderson Dias Vieira de Souza  Antonio Camilo Arguelho ViannaAntonia Railda Roel 《Scientia Horticulturae》2011

The purpose of this study was to evaluate the physico-chemical characteristics and the post-harvest loss of mass of curly lettuce (Lactuca sativa L.) cv. Verônica that was grown in a protective environment with applications of biopesticides. The curly lettuce was treated by spraying with neem oil, cassava flour wastewater (manipueira), biofertiliser or the control treatment of deltamethrin. We determined the weight, circumference, dry matter, ash, crude protein, total phenols and minerals profile for the heads of lettuce. After harvesting, the lettuce was packed into opened plastic bags and kept at 5 °C for 5 days to evaluate its weight loss. No differences were observed among the treatments for the physico-chemical parameters. The lettuce that was sprayed with manipueira or biofertiliser had the greatest weight loss during storage. The achievement of similar yields with cheaper products suggests a benefit of using organic bioinsecticides.  相似文献   

Effect of a new thermal treatment in combination with saprobic fungal incubation on the phytotoxicity level of alperujo     

Sampedro I  Aranda E  Rodríguez-Gutiérrez G  Lama-Muñoz A  Ocampo JA  Fernández-Bolaños J  García-Romera I 《Journal of agricultural and food chemistry》2011,59(7):3239-3245

Byproducts generated from food industries, such as olive oil mills, have been studied to decrease harmful pollution and their environmental consequences. In this work, a new thermal pretreatment and saprobic fungal incubation to detoxify alperujo (two-phase olive mill waste) have been evaluated in view of its use as fertilizer in agriculture. The sequential use of both methods simplifies the thermal conditions and incubation times of the fungal treatment. Optimization of the thermal treatment from 150 to 170 °C for 45 and 15 min, respectively, reduced the incubation time with Coriolpsis rigida from 20 to 10 weeks needed to reduce phytotoxic effects on tomato plants. Therefore, the combination of thermal and biological treatments will allow the development of the potential benefits of alperujo to improve nutrients in agricultural soil.  相似文献   

Dual plant host effects on two arbuscular mycorrhizal fungi     

Antonio J. Golubski 《Pedobiologia》2011,54(4):209-216

Mycorrhizal fungi may simultaneously associate with multiple plant hosts, and the implications of this for the fungi involved are not well understood. To address this question, two arbuscular mycorrhizal fungi (AMF), Glomus clairoideum (a treatment referred to as “Glo”) and Scutellospora fulgida (a treatment referred to as “Scut”), were grown separately in pots that each consisted of two plant compartments separated by a root-free-compartment (RFC). Fungi within each two-plant-compartment pot were exposed to either two individuals of indiangrass (Sorghastrum nutans), two individuals of big bluestem (Andropogon gerardii), or one of each. A non-inoculated treatment (“Non”) was included to help gauge the potential influence of greenhouse contaminant fungi, cross-contamination, or any misidentification of non-AMF hyphae. The two host species had additive effects on the growth of AM hyphae in plant compartments of Scut, Glo, and Non pots, and in the RFCs of Scut pots. In Glo RFCs, however, they were antagonistic in their effects. Synergism between hosts in Non RFCs suggested that any potential contaminants or misidentification could not explain this result. Underyielding was not seen in shoot weight, root weight, or root length in dual host pots, and also therefore could not explain the result. Hyphal growth in the Scut treatment was evenly distributed between the RFC and plant compartments (or marginally skewed toward the RFC), while hyphal growth in the Glo treatment was skewed toward plant compartments (nearer roots). However, hyphal lengths were more highly correlated across plant compartments within a common pot in the Glo treatment, suggesting that this AMF bridged the RFC to experience the entire two-host pot as a single environment to a greater extent than Scut did. These AMF differed in how they responded to both the species composition of the two-host environment and its spatial structure; potential implications for mycorrhizal community dynamics are discussed.  相似文献