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991.
Shaping species with ephemeral boundaries: the distribution and genetic structure of desert tortoise (Gopherus morafkai) in the Sonoran Desert region 下载免费PDF全文
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Alice?AlbertiniEmail authorView authors OrcID profile Roberto?Pizzolotto Ruggero?Petacchi 《BioControl》2017,62(1):71-83
The role of carabids (Coleoptera: Carabidae) for pest control service in perennial crop systems has been scarcely investigated. We addressed this knowledge gap exploring activity patterns and traits of adult carabids dwelling olive orchard agroecosystems as potential natural enemies of third instar larvae and pupae of Bactrocera oleae (Diptera: Tephritidae). Olive orchard supported a well-structured carabid assemblage, whose species phenologies revealed a temporal overlapping within the pest cycle. The assemblage of adjacent woody semi-natural habitats is more of conservation interest, but may play a weaker role in B. oleae control provisioning. We suggest the identification of carabids main traits for B. oleae conservation biological control as a cost-effective strategy for addressing future attention and resources only to those predators that satisfy basic requirements. This research may open new scenarios on management interventions to both conserve predators and encourage alternative approaches against olive orchards pest. 相似文献
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Maaran Michael Rajah Mathieu Hubert Elodie Bishop Nell Saunders Remy Robinot Ludivine Grzelak Delphine Planas Jrmy Dufloo Stacy Gellenoncourt Alice Bongers Marija Zivaljic Cyril Planchais Florence GuivelBenhassine Franoise Porrot Hugo Mouquet Lisa A Chakrabarti Julian Buchrieser Olivier Schwartz 《The EMBO journal》2021,40(24)
Severe COVID‐19 is characterized by lung abnormalities, including the presence of syncytial pneumocytes. Syncytia form when SARS‐CoV‐2 spike protein expressed on the surface of infected cells interacts with the ACE2 receptor on neighboring cells. The syncytia forming potential of spike variant proteins remain poorly characterized. Here, we first assessed Alpha (B.1.1.7) and Beta (B.1.351) spread and fusion in cell cultures, compared with the ancestral D614G strain. Alpha and Beta replicated similarly to D614G strain in Vero, Caco‐2, Calu‐3, and primary airway cells. However, Alpha and Beta formed larger and more numerous syncytia. Variant spike proteins displayed higher ACE2 affinity compared with D614G. Alpha, Beta, and D614G fusion was similarly inhibited by interferon‐induced transmembrane proteins (IFITMs). Individual mutations present in Alpha and Beta spikes modified fusogenicity, binding to ACE2 or recognition by monoclonal antibodies. We further show that Delta spike also triggers faster fusion relative to D614G. Thus, SARS‐CoV‐2 emerging variants display enhanced syncytia formation. 相似文献
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Unrepaired DNA double-strand breaks (DSBs) produced by ionizing radiation (IR) are a major determinant of cell killing. To determine the contribution of DNA repair pathways to the well-established cell cycle variation in IR sensitivity, we compared the radiosensitivity of wild-type CHO cells to mutant lines defective in nonhomologous end joining (NHEJ), homologous recombination repair (HRR), and the Fanconi anemia pathway. Cells were irradiated with IR doses that killed approximately 90% of each asynchronous population, separated into synchronous fractions by centrifugal elutriation, and assayed for survival (colony formation). Wild-type cells had lowest resistance in early G1 and highest resistance in S phase, followed by declining resistance as cells move into G2/M. In contrast, HR-defective cells (xrcc3 mutation) were most resistant in early G1 and became progressively less resistant in S and G2/M, indicating that the S-phase resistance in wild-type cells requires HRR. Cells defective in NHEJ (dna-pk(cs) mutation) were exquisitely sensitive in early G1, most resistant in S phase, and then somewhat less resistant in G2/M. Fancg mutant cells had almost normal IR sensitivity and normal cell cycle dependence, suggesting that Fancg contributes modestly to survival and in a manner that is independent of cell cycle position. 相似文献
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Medeiros FP Santos MA Regis L Rios EM Rolim Neto PJ 《Memórias do Instituto Oswaldo Cruz》2005,100(4):431-434
This study aimed to analyze the final fermentation culture of Bacillus sphaericus 2362, standardize it and develop an active tablet formulation for use in urban mosquito breeding sites. It was performed in three phases: analysis and standardization of a B. sphaericus fermented culture; physical, chemical, and biological analysis of the active powder (solubility, residual humidity, particle size, resting angle, flowing off time, compacted density, and biological activity against Culex quinquefasciatus larvae); and the development of fast-disintegrating tablets. Five formulations with differing compositions were developed and a UV protector was added to the selected formulation. The formulation products with or without UV protector, as well as the active powder caused 100% larval mortality from 1 day to 2 months after a single treatment under simulated field conditions. These results show that the UV protector does not affect the initial larvicide activity of B. sphaericus, nor its persistence over a period of two months. 相似文献
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Meira Fields Charles G. Lewis Alice Rose James C. Smith Sheldon Reiser 《Biological trace element research》1986,10(4):335-346
The present investigation was designed to study the uptake of67Cu when administered directly, into the portal vein, along with either functose or glucose, by the liver and extrahepatic
tissues. Following weaning, male Sprague-Dawley rats were fed for 3 wk either commercial laboratory ration (chow) or semipurified
diets deficient in Cu (0.6 ppm) or supplemented with Cu (6.0 ppm) and containing 62% carbohydrate as either fructuse or cornstarch.
After an overnight fast, a single dose of rat plasma (0.1 mL) containing fructose or glucose extrinsically labeled with67Cu was injected directly into their portal vein. Although not always statistically significant, rats fed chow retained more
radioactivity in the liver and several extrahepatic tissues when67Cu was administered with fructose than with glucose. Regardless of Cu status, rats fed diets containing fructose retained
more radioactivity in extrahepatic tissues than rats fed starch. There was an increased uptake of67Cu by the liver, blood, muscle, and fat pad when fructose as compared to glucose was injected in combination with the isotope.
These data strongly suggest that Cu requirements or utilization are greater when fructose is the main dietary carbohydrate.
The results may also in part explain the reason for the increased severity of Cu deficiency in rats fed fructose. 相似文献