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101.
Macke E Magalhães S Khan HD Luciano A Frantz A Facon B Olivieri I 《Proceedings. Biological sciences / The Royal Society》2011,278(1708):1054-1063
Haplodiploid species display extraordinary sex ratios. However, a differential investment in male and female offspring might also be achieved by a differential provisioning of eggs, as observed in birds and lizards. We investigated this hypothesis in the haplodiploid spider mite Tetranychus urticae, which displays highly female-biased sex ratios. We show that egg size significantly determines not only larval size, juvenile survival and adult size, but also fertilization probability, as in marine invertebrates with external fertilization, so that female (fertilized) eggs are significantly larger than male (unfertilized) eggs. Moreover, females with on average larger eggs before fertilization produce a more female-biased sex ratio afterwards. Egg size thus mediates sex-specific egg provisioning, sex and offspring sex ratio. Finally, sex-specific egg provisioning has another major consequence: male eggs produced by mated mothers are smaller than male eggs produced by virgins, and this size difference persists in adults. Virgin females might thus have a (male) fitness advantage over mated females. 相似文献
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J C Nou?t M Kujas 《Comptes rendus des séances de la Société de biologie et de ses filiales》1986,180(6):625-628
The situation of mitoses in the adrenal glands of the rat has been studied by measuring the distance between each of them (3,061 in the whole) at the surface. The curve of their distribution, logarithmic-normal type, shows that they are the most numerous in germinative zone classically described, but that they appear down to the depth of inner fascicula. 相似文献
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106.
Mickaël Mateos Nikolina Makivic Yee‐Seul Kim Benoît Limoges Vronique Balland 《Liver Transplantation》2020,10(23)
Rechargeable batteries based on MnO2 cathodes, able to operate in mild aqueous electrolytes, have attracted attention due to their appealing features for the design of low‐cost stationary energy storage devices. However, the charge/discharge mechanism of MnO2 in such media is still a matter of debate. Here, an in‐depth quantitative spectroelectrochemical analysis of MnO2 thin‐films provides a set of unrivaled mechanistic insights. A major finding is that charge storage occurs through the reversible two‐electron faradaic conversion of MnO2 into Mn2+ in the presence of a wide range of weak Brønsted acids, including the [Zn(H2O)6]2+ or [Mn(H2O)6]2+ complexes present in aqueous Zn/MnO2 batteries. Furthermore, it is shown that buffered electrolytes loaded with Mn2+ are ideal to achieve highly reversible conversion of MnO2 with both high gravimetric capacity and remarkably stable charging/discharging potentials. In the most favorable case, a record gravimetric capacity of 450 mA·h·g?1 is obtained at a high rate of 1.6 A·g?1, with a Coulombic efficiency close to 100% and a MnO2 utilization of 84%. Overall, the present results challenge the common view on MnO2 the charge storage mechanism in mild aqueous electrolytes and underline the benefit of buffered electrolytes for high‐performance rechargeable aqueous batteries. 相似文献
107.
Marko Jot Benjamin Lipovek Botjan Glaar Amran Al‐Ashouri Kristijan Brecl Gaper Mati
Artiom Magomedov Vytautas Getautis Marko Topi
Steve Albrecht 《Liver Transplantation》2020,10(25)
Perovskite solar cells (PSC) have shown that under laboratory conditions they can compete with established photovoltaic technologies. However, controlled laboratory measurements usually performed do not fully resemble operational conditions and field testing outdoors, with day‐night cycles, changing irradiance and temperature. In this contribution, the performance of PSCs in the rooftop field test, exposed to real weather conditions is evaluated. The 1 cm2 single‐junction devices, with an initial average power conversion efficiency of 18.5% are tracked outdoors in maximum power point over several weeks. In parallel, irradiance and air temperature are recorded, allowing us to correlate outside factors with generated power. To get more insight into outdoor device performance, a comprehensive set of laboratory measurements under different light intensities (10% to 120% of AM1.5) and temperatures is performed. From these results, a low power temperature coefficient of ?0.17% K?1 is extracted in the temperature range between 25 and 85 °C. By incorporating these temperature‐ and light‐dependent PV parameters into the energy yield model, it is possible to correctly predict the generated energy of the devices, thus validating the energy yield model. In addition, degradation of the tested devices can be tracked precisely from the difference between measured and modelled power. 相似文献
108.
Jean Legeay Claude Husson Benjamin Boudier Eliane Louisanna Christopher Baraloto Heidy Schimann Benoît Marcais Marc Buée 《Environmental microbiology》2020,22(12):5019-5032
The genus Phytophthora represents a group of plant pathogens with broad global distribution. The majority of them cause the collar and root-rot of diverse plant species. Little is known about Phytophthora communities in forest ecosystems, especially in the Neotropical forests where natural enemies could maintain the huge plant diversity via negative density dependence. We characterized the diversity of soil-borne Phytophthora communities in the North French Guiana rainforest and investigated how they are structured by host identity and environmental factors. In this little-explored habitat, 250 soil cores were sampled from 10 plots hosting 10 different plant families across three forest environments (Terra Firme, Seasonally Flooded and White Sand). Phytophthora diversity was studied using a baiting approach and metabarcoding (High-Throughput Sequencing) on environmental DNA extracted from both soil samples and baiting-leaves. These three approaches revealed very similar communities, characterized by an unexpected low diversity of Phytophthora species, with the dominance of two cryptic species close to Phytophthora heveae. As expected, the Phytophthora community composition of the French Guiana rainforest was significantly impacted by the host plant family and environment. However, these plant pathogen communities are very small and are dominated by generalist species, questioning their potential roles as drivers of plant diversity in these Amazonian forests. 相似文献
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Tóth Ákos Bata-Vidács Ildikó Kosztik Judit Máté Rózsa Kutasi József Tóth Erika Bóka Károly Táncsics András Nagy István Kovács Gábor Kukolya József 《Antonie van Leeuwenhoek》2021,114(10):1575-1584
Antonie van Leeuwenhoek - A Gram-reaction-negative halotolerant bacterial strain, designated Ka21T, was isolated from agricultural soil and characterised using a polyphasic approach to determine... 相似文献