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991.
Anabella Aguilera Luis Aubriot Ricardo O. Echenique Graciela L. Salerno Beatriz M. Brena Macarena Pírez Sylvia Bonilla 《Hydrobiologia》2017,794(1):241-255
Blooms of Nostocales (Cyanobacteria) are thought to be invading subtropical and temperate water bodies. According to nutrient stoichiometry and physiological differences between cyanobacterial groups, the replacement of non-heterocystous species by Nostocales is favored when dissolved inorganic nitrogen decreases. However, some studies have shown different trends. We used laboratory bioassays to evaluate the concomitant effects of light and nutrient enrichment on phytoplankton assemblages dominated by non-heterocystous filamentous cyanobacteria. Three nutrient conditions (no addition, addition of phosphate, and addition of nitrate and phosphate) and two light intensities (40 and 80 µmol photon m?2 s?1) were assayed. Nostocales replaced or co-dominated with non-heterocystous species in all treatments by the end of the study. The shift in community composition towards Nostocales dominance led to an increase in species richness, which suggests that species with different eco-physiological traits may have differential impacts on diversity. The highest saxitoxin concentrations were measured in no addition treatments, which could link production to nutritional stress. Nostocales featured high phenotypic plasticity in terms of changes in average trichome volume and growth rates. These results help to have a better understanding of the conditions under which Nostocales predominance can occur. 相似文献
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Spampinato Mariarita Sferrazzo Giuseppe Pittalà Valeria Di Rosa Michelino Vanella Luca Salerno Loredana Sorrenti Valeria Carota Giuseppe Parrinello Nunziatina Raffaele Marco Tibullo Daniele Li Volti Giovanni Barbagallo Ignazio 《Molecular biology reports》2020,47(3):1949-1964
Molecular Biology Reports - Non-small cell lung cancer (NSCLC) remains the leading cause of cancer-related death mainly due to its high metastatic rate. Impairment of redox homeostasis mechanisms... 相似文献
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An original method is described for the determination in human plasma of 4-hydroxy-4-androstene-3,17-dione (4-OHA), a potent aromatase inhibitor, by isotope dilution mass-spectrometry using 7,7-[2H2]-4-OHA as internal standard. This compound was synthesized starting from 7,7-[2H2]-4-androstene-3,17-dione. The procedure includes an extraction step using an Extrelut 1 column and a derivatization with N,o-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The minimum detection level of the method is 0.650 pg and the coefficients of variation for the 0.5 ng/ml (plasma) and 5 ng/ml (plasma) concentrations are 3.2% (within assay) and 6.7% (between assay) and 1.86% (within assay) and 2.3% (between assay) respectively. 相似文献
998.
Silvana Piersanti Gianandrea Salerno Viviana Di Pietro Leonardo Giontella Manuela Rebora Albyn Jones Ola M. Fincke 《Ecology and evolution》2021,11(9):4399
Search image formation, a proximal mechanism to maintain genetic polymorphisms by negative frequency‐dependent selection, has rarely been tested under natural conditions. Females of many nonterritorial damselflies resemble either conspecific males or background vegetation. Mate‐searching males are assumed to form search images of the majority female type, sexually harassing it at rates higher than expected from its frequency, thus selectively favoring the less common morph. We tested this and how morph coloration and behavior influenced male perception and intersexual encounters by following marked Ischnura elegans and noting their reactions to conspecifics. Contrary to search image formation and associative learning hypotheses, although males encountered the minority, male‐like morph more often, sexual harassment and clutch size were similar for both morphs. Prior mating attempts or copula with morphs did not affect a male''s subsequent reaction to them; males rarely attempted matings with immature females or males. Females mated early in the day, reducing the opportunity for males to learn their identity beforehand. Once encountered, the male‐like morph was more readily noticed by males than the alternative morph, which once noticed was more likely to receive mating attempts. Flexible behavior gave morphs considerable control over their apparency to males, influencing intersexual encounters. Results suggested a more subtle proximal mechanism than male learning maintains these color polymorphisms and call for inferences of learning to be validated by behavior of wild receivers and their signalers. 相似文献
999.
Abstract The marine flora of the Isle of Pianosa (Isles Tremiti). – The little Isle Pianosa (Middle Adriatic) presents an algal flora typical for clear, deep seas. Its main components are here described. Endolithic flora on calcareous rocks has been particularly well examined. 相似文献
1000.
Knirsch Marcos Camargo Dell’Anno Filippo Salerno Marco Larosa Claudio Polakiewicz Bronislaw Eggenhöffner Roberto Converti Attilio 《Bioprocess and biosystems engineering》2017,40(3):431-438
Bioprocess and Biosystems Engineering - Polyhemoglobin produced from pure bovine hemoglobin by reaction with PEG bis(N-succynimidil succinate) as a cross-linking agent was encapsulated in gelatin... 相似文献