NIOSH and the CDC reorganization     

Key MM  Robbins A  Millar JD  Rosenstock L 《Science (New York, N.Y.)》2004,305(5684):607

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Martian craters: number density     

Marcus AH 《Science (New York, N.Y.)》1968,160(3834):1333-1335

The incremental frequency distribution of Martian crater diameters larger than 20 to 30 kilometers follows an inverse-square law, with density equal to that of craters on the lunar continents. This finding accords with the prediction that lunar continents and the Martian surface carry an equilibrium density (saturation) of craters originating in meteoroidal impact. Therefore crater statistics alone cannot be used for estimation of the age of the Martian surface.  相似文献   

Expression of interleukin-10 activity by Epstein-Barr virus protein BCRF1   总被引：34，自引：0，他引：34  

D H Hsu  R de Waal Malefyt  D F Fiorentino  M N Dang  P Vieira  J de Vries  H Spits  T R Mosmann  K W Moore 《Science (New York, N.Y.)》1990,250(4982):830-832

Cytokine synthesis inhibitory factor (CSIF; interleukin-10), a product of mouse TH2 T cell clones that inhibits synthesis of cytokines by mouse TH1 T cell clones, exhibits extensive sequence similarity to an uncharacterized open reading frame in the Epstein-Barr virus BCRF1. Recombinant BCRF1 protein mimics the activity of interleukin-10, suggesting that BCRF1 may have a role in the interaction of the virus with the host's immune system.  相似文献   

Statement on scientific publication and security     

Atlas R  Campbell P  Cozzarelli NR  Curfman G  Enquist L  Fink G  Flanagin A  Fletcher J  George E  Hammes G  Heyman D  Inglesby T  Kaplan S  Kennedy D  Krug J  Levinson R  Marcus E  Metzger H  Morse SS  O'Brien A  Onderdonk A  Poste G  Renault B  Rich R  Rosengard A  Salzburg S  Scanlan M  Shenk T  Tabor H  Varmus H  Wimmer E  Yamamoto K;Journal Editors  Authors Group 《Science (New York, N.Y.)》2003,299(5610):1149

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Genetic structure of human populations   总被引：1，自引：0，他引：1  

Rosenberg NA  Pritchard JK  Weber JL  Cann HM  Kidd KK  Zhivotovsky LA  Feldman MW 《Science (New York, N.Y.)》2002,298(5602):2381-2385

We studied human population structure using genotypes at 377 autosomal microsatellite loci in 1056 individuals from 52 populations. Within-population differences among individuals account for 93 to 95% of genetic variation; differences among major groups constitute only 3 to 5%. Nevertheless, without using prior information about the origins of individuals, we identified six main genetic clusters, five of which correspond to major geographic regions, and subclusters that often correspond to individual populations. General agreement of genetic and predefined populations suggests that self-reported ancestry can facilitate assessments of epidemiological risks but does not obviate the need to use genetic information in genetic association studies.  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   

Adapting the IUCN Red List criteria for invertebrates     

Pedro Cardoso  Paulo A.V. Borges  Kostas A. Triantis  Miguel A. Ferrández  José L. Martín 《Biological conservation》2011,(10):2432-2440

The IUCN Red List is the most useful list of species that are at risk for extinction worldwide, as it relies on a number of objective criteria. Nevertheless, there is a taxonomic bias that excludes species with small body sizes, narrow distribution ranges and low dispersal abilities, which constitute the vast majority of the planet’s biota, particularly local endemics.By evaluating each IUCN criterion separately, we (i) identify the shortcomings for invertebrate applications, (ii) explain how risk categories may be wrongly applied due to inapplicable and/or misleading thresholds, (iii) suggest alternative ways of applying the existing criteria in a more realistic way and (iv) suggest possible new criteria that were not considered in the current evaluation framework but that could allow a more comprehensive and effective assessment of invertebrates.By adapting the criteria to rely more explicitly on the Area of Occupancy and the Extent of Occurrence, their respective trends and by using ecological modelling methods, the criteria’s applicability would be increased. The change in some thresholds or, eventually, the creation of sub-categories would further increase their adequacy. Additionally, co-extinction could be introduced as an explicit part of the classification process.As a case study, we evaluated 48 species of Azorean arthropods and Iberian spiders according to the current criteria. More than one-quarter (27%) of all evaluated species were classified as Critically Endangered, 19% as Endangered, 6% as Vulnerable and 8% as Least Concern. The remaining 40% did not have enough data to reach a classification.  相似文献   

Characterization of wildfires in Portugal     

S. Marques  J. G. Borges  J. Garcia-Gonzalo  F. Moreira  J. M. B. Carreiras  M. M. Oliveira  A. Cantarinha  B. Botequim  J. M. C. Pereira 《European Journal of Forest Research》2011,130(5):775-784

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Pterocarpan profiles for soybean leaves at different growth stages and investigation of their glycosidase inhibitions     

Yuk HJ  Curtis-Long MJ  Ryu HW  Jang KC  Seo WD  Kim JY  Kang KY  Park KH 《Journal of agricultural and food chemistry》2011,59(23):12683-12690

Soybean leaves are eaten as seasonal edible greens in Korea. Analysis of the ethyl acetate extract of these leaves showed that it exhibited potent and selective neuraminidase inhibition, which began at the R3 stage and peaked at R7. Ten pterocarpans, including the new 6a-hydroxypterocarpan 10, were isolated from soybean leaves and their inhibition activities tested against a range of glycosidases. The relationship between structure and enzyme inhibition was investigated: 6a-hydroxypterocarpans exhibited much higher inhibition against neuraminidase (IC(50) = 2.4-89.4 μM) than α-glucosidase (IC(50) = 90.4-?>100 μM). Glyceollin VII (7) displayed 40-fold greater activity (IC(50) = 2.4 μM) against neuraminidase than α-glucosidase (IC(50) = 90.4 μM). On the other hand, coumestanes (1-3) were good α-glucosidase inhibitors (IC(50) = 6.0-42.6 μM). In kinetic analysis, the most potent neuraminidase inhibitors (5-10) were noncompetitive. HPLC analysis indicated that most pterocarpan synthesis began from the R3 stage, and a rapid change of pterocarpan concentrations was observed between the R4 and R7 stages.  相似文献   

Genetic diversity and a PCR-based method for Xanthomonas axonopodis detection in passion fruit     

Munhoz CF  Weiss B  Hanai LR  Zucchi MI  Fungaro MH  Oliveira AL  Monteiro-Vitorello CB  Vieira ML 《Phytopathology》2011,101(4):416-424

Xanthomonas axonopodis pv. passiflorae causes bacterial spot in passion fruit. It attacks the purple and yellow passion fruit as well as the sweet passion fruit. The diversity of 87 isolates of pv. passiflorae collected from across 22 fruit orchards in Brazil was evaluated using molecular profiles and statistical procedures, including an unweighted pair-group method with arithmetical averages-based dendrogram, analysis of molecular variance (AMOVA), and an assigning test that provides information on genetic structure at the population level. Isolates from another eight pathovars were included in the molecular analyses and all were shown to have a distinct repetitive sequence-based polymerase chain reaction profile. Amplified fragment length polymorphism technique revealed considerable diversity among isolates of pv. passiflorae, and AMOVA showed that most of the variance (49.4%) was due to differences between localities. Cluster analysis revealed that most genotypic clusters were homogeneous and that variance was associated primarily with geographic origin. The disease adversely affects fruit production and may kill infected plants. A method for rapid diagnosis of the pathogen, even before the disease symptoms become evident, has value for producers. Here, a set of primers (Xapas) was designed by exploiting a single-nucleotide polymorphism between the sequences of the intergenic 16S-23S rRNA spacer region of the pathovars. Xapas was shown to effectively detect all pv. passiflorae isolates and is recommended for disease diagnosis in passion fruit orchards.  相似文献