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First Record of Teratopactus nodicollis (Coleoptera: Curculionidae) in Dry Bean (Phaseolus vulgaris)
Observations on the bioecology and damage of Teratopactus nodicollis Boheman on Phaseolus vulgaris were carried out on field samples by assessing the number of larvae and root damage in 40?ha of a dry bean field from the Federal District, Brazil (16°4??28.41???W; 47°30??21.13???S). Larvae caused the greatest damage at the stage of germination, emergence, and primary leaves, producing 50?% stand reduction. Most larvae pupated in August and September, and adult emergence occurred in middle October. Some larvae were infected with the fungus Metarhizium spp., a biological agent that would be naturally controlling this insect. 相似文献
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Xiao Xiao Mei Xu Chao Yang Yao Yao Li-na Liang Philip ED Chung Qun Long Eldad Zacksenhaus Zhixu He Sheng Liu Yaacov Ben-David 《Bioorganic & medicinal chemistry》2018,26(23-24):6096-6104
Carbazole derivatives show anti-cancer activity and are of great interest for drug development. In this study, we synthesized and analyzed several new alkylamide derivatives of racemocin B, a natural indolo[3,2-a]carbazole molecule originally isolated from the green alga Caulerpa racemose. Several alkylamide derivatives were found to exhibit moderate to strong growth inhibition against human breast cancer cell lines. They induced G2/M cell cycle arrest and apoptosis in the aggressive triple-negative breast cancer cell line MDA-MB-231. Among these derivatives, compound 25 with the lowest IC50 induced cell death by suppressing autophagy. This was accompanied by inhibition of autophagic flux and accumulation of autophagy protein 1 light chain 3, LC3II, and p62. The novel alkylamide derivative offers a potential new treatment for human breast cancer. 相似文献
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JEANNE MARIE ROBERTSON ERICA BREE ROSENBLUM 《Biological journal of the Linnean Society. Linnean Society of London》2009,98(2):243-255
Animal social signals are important for population recognition, communication, and mate choice. Although natural selection often favours cryptic coloration, sexual selection can underlie patterns of coloration that function in inter- or intrasexual communication. We compared social signal coloration of three lizard species across a substrate colour ecotone in New Mexico. These species exhibit cryptic blanched dorsal coloration on the gypsum dunes of White Sands and dark coloration on the surrounding desert soils. We detected corresponding population divergence in colour used for intra- ( Aspidoscelis inornata , Sceloporus undulatus ) or inter- ( Holbrookia maculata ) sexual signalling. Although the magnitude and direction of change in coloration varied among taxa, differences in hue and chroma accounted for more variation in social coloration than for dorsal coloration. The relative conspicuousness of social signals also varied across the ecotone. We discuss the possibilities that divergent signalling colours in this system are the result of: (1) stochastic processes, (2) direct selection, and/or (3) a correlated response to natural selection on dorsal coloration. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 243–255. 相似文献
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BENJAMIN POULTER FRED HATTERMANN ED HAWKINS SÖNKE ZAEHLE STEPHEN SITCH NATALIA RESTREPO‐COUPE URSULA HEYDER WOLFGANG CRAMER 《Global Change Biology》2010,16(9):2476-2495
Climate change science is increasingly concerned with methods for managing and integrating sources of uncertainty from emission storylines, climate model projections, and ecosystem model parameterizations. In tropical ecosystems, regional climate projections and modeled ecosystem responses vary greatly, leading to a significant source of uncertainty in global biogeochemical accounting and possible future climate feedbacks. Here, we combine an ensemble of IPCC‐AR4 climate change projections for the Amazon Basin (eight general circulation models) with alternative ecosystem parameter sets for the dynamic global vegetation model, LPJmL. We evaluate LPJmL simulations of carbon stocks and fluxes against flux tower and aboveground biomass datasets for individual sites and the entire basin. Variability in LPJmL model sensitivity to future climate change is primarily related to light and water limitations through biochemical and water‐balance‐related parameters. Temperature‐dependent parameters related to plant respiration and photosynthesis appear to be less important than vegetation dynamics (and their parameters) for determining the magnitude of ecosystem response to climate change. Variance partitioning approaches reveal that relationships between uncertainty from ecosystem dynamics and climate projections are dependent on geographic location and the targeted ecosystem process. Parameter uncertainty from the LPJmL model does not affect the trajectory of ecosystem response for a given climate change scenario and the primary source of uncertainty for Amazon ‘dieback’ results from the uncertainty among climate projections. Our approach for describing uncertainty is applicable for informing and prioritizing policy options related to mitigation and adaptation where long‐term investments are required. 相似文献
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Abstract: Morphological and reproductive features and cell wall ultrastructure and biochemistry of Proterozoic acritarchs are used to determine their affinity to modern algae. The first appearance datum of these microbiota is traced to infer a minimum age of the divergence of the algal classes to which they may belong. The chronological appearance of microfossils that represent phycoma‐like and zygotic cysts and vegetative cells and/or aplanospores, respectively, interpreted as prasinophyceaen and chlorophyceaen microalgae is related to the Viridiplantae phylogeny. An inferred minimum age of the Chlorophyte origin is before c. 1800 Ma, the Prasinophyceae at c. 1650 Ma and the Chlorophyceae at c. 1450 Ma. These divergence times differ from molecular clock estimates, and the palaeontological evidence suggests that they are older. 相似文献
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LEONARD A. ROSENBLUM 《American anthropologist》1973,75(6):2027-2027
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Pehun Pereyra Gerber Lidia M. Duncan Edward JD Greenwood Sara Marelli Adi Naamati Ana Teixeira-Silva Thomas WM Crozier Ildar Gabaev Jun R. Zhan Thomas E. Mulroney Emily C. Horner Rainer Doffinger Anne E. Willis James ED Thaventhiran Anna V. Protasio Nicholas J. Matheson 《PLoS pathogens》2022,18(2)
Efforts to define serological correlates of protection against COVID-19 have been hampered by the lack of a simple, scalable, standardised assay for SARS-CoV-2 infection and antibody neutralisation. Plaque assays remain the gold standard, but are impractical for high-throughput screening. In this study, we show that expression of viral proteases may be used to quantitate infected cells. Our assays exploit the cleavage of specific oligopeptide linkers, leading to the activation of cell-based optical biosensors. First, we characterise these biosensors using recombinant SARS-CoV-2 proteases. Next, we confirm their ability to detect viral protease expression during replication of authentic virus. Finally, we generate reporter cells stably expressing an optimised luciferase-based biosensor, enabling viral infection to be measured within 24 h in a 96- or 384-well plate format, including variants of concern. We have therefore developed a luminescent SARS-CoV-2 reporter cell line, and demonstrated its utility for the relative quantitation of infectious virus and titration of neutralising antibodies. 相似文献