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131.
In marine ecosystems, the most significant migration observed in terms of biomass distribution is the one connected with the vertical movements in the water column. In the present study, the vertical profiles of the mesopelagic shrimps Gennadas elegans, Eusergestes arcticus, Sergia robusta, and the epipelagic Parasergestes vigilax in the Balearic Sea (western Mediterranean), during the stratified (summer) and non-stratified (autumn) hydrographic conditions, were investigated through their ontogeny, from the larval to adult stages. The mesopelagic adults were observed to move down to the deeper layers during the night more than during the daylight hours. Most larvae aggregated within the limits of the upper water column. The P. vigilax larvae were collected only during the stratified period. The first two larval stages vertical distribution indicates that the mesopelagic crustacean spawning could occur at greater depths. During the non-stratified period, the larvae of the mesopelagic species tended to remain at about 500 m depth at night, rising towards the upper layers at sunrise. Vertical patterns are discussed, as strategies associated with predator–prey trade-offs. To our knowledge, the present study is the first such attempt to jointly analyze the vertical migrations of the developmental stages of the pelagic shrimps in the Mediterranean Sea.  相似文献   
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In this study, we investigated the molecular phylogenetic divergence and historical biogeography of cave crickets belonging to the genus Troglophilus (Orthoptera, Rhaphidophoridae) from caves in eastern Mediterranean and Anatolia regions. Three mitochondrial DNA genes (COI, 12S rDNA, and 16S rDNA) and two nuclear ones (18S rDNA and 28S rDNA) were amplified and partially sequenced to reconstruct phylogenetic relationships among most of the known Troglophilus species. Results showed a well‐resolved phylogeny with three main clades representing the Balkan, the Anatolian, and the Cycladian–Cretan lineages. Based on Bayesian analyses, we applied a relaxed molecular clock model to estimate the divergence times between these three lineages. Dating estimates indicate that radiation of the ingroup might have been triggered by the opening of the Mid‐Aegean trench, while the uplift of the Anatolian Plateau in Turkey and the changes of relief, emergence, and disappearance of orographic and hydrographical barriers in the Balkan Peninsula are potential paleogeographic events responsible for the initial diversification of the genus Troglophilus. A possible biogeographic scenario, reconstructed using S‐DIVA with RASP software, suggested that the current distribution of Troglophilus species can be explained by a combination of both dispersal and vicariance events that occurred in particular in the ancestral populations. The radiation of Troglophilus species likely started from the Aegean and proceeded eastward to Anatolia and westward to the Balkan region. Results are additionally compared to those available for Dolichopoda, the only other representative genus of Rhaphidophoridae present in the Mediterranean area.  相似文献   
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Animal communication is a complex behavior that is influenced by abiotic and biotic factors of the environment. Glassy‐winged sharpshooters (GWSS), Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae), primarily use vibrational signaling for courtship communication. Because GWSS is a major pest, transmitting the plant pathogenic bacterium Xylella fastidiosa Wells et al., interruption of communication is a possible avenue for control. Playback of white noise, pre‐recorded female signals, and artificial female noise (continuously overlapping female signals) significantly reduced mating of GWSS when compared to silent control mating trials. Furthermore, to begin to determine the mechanism underlying playback control, female signaling activity was recorded in the presence of stimuli. In response to playback of female signals, females signaled (duet‐like) more often than females tested in the absence of playback. After the first playback, almost two‐thirds of females signaled a response within 3 s. Additionally, one‐third of the females signaled within 1 s after cessation of white noise, and significantly more in the time periods following noise termination. Results highlight how GWSS responds to differing competitive disturbances in the environment and lays important ground work that possibly could be used to develop pesticide‐free control methods.  相似文献   
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Olive is one of the most important tree crops in the Mediterranean region, because of its ability to grow and produce acceptable yields under limited water availability. In this study, the drought tolerance of an olive cultivar Canino was compared to the performance of its derived transgenic line expressing osmotin gene from tobacco, obtained by Agrobacterium-mediated transformation of Canino cultivar. Shoot cultures of both wild-type (wt) and transgenic lines were exposed to drought stress over a 28-day period, and their differential responses to in vitro-drought stress were investigated. After exposure to PEG, most of the shoots from wt plants resulted in damage and exhibited decreased levels of chlorophyll, while those of transgenic line did not show injuries and showed a normal growth even when exposed to the highest PEG concentration (4%). After preliminary evaluation we characterized Canino AT17-1, by measuring several physiological parameters, including the activities of the antioxidant enzymes (POD and CAT), and the content of malondialdehyde (MDA). Both the activity of catalase and the proline content were higher in the leaves of the transgenic shoots compared to wt plants. Consequently, it was observed that the transgenic line accumulated less MDA indicating that the presence of the osmotin gene protected the cell membrane from damage by lipid peroxidation. Together, these results could suggest that the transgenic line Canino AT17-1 was more efficient in the activation of defense responses against oxidative stress with respect to the Canino wt. The further finding that the transgenic shoots also showed higher proline accumulation supported the hypothesis that the osmotin gene conferred to transgenic shoots increased tolerance to drought stress compared with the wt.  相似文献   
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With the aim of developing new functional foods, a traditional product, the table olive, was used as a vehicle for incorporating probiotic bacterial species. Survival on table olives of Lactobacillus rhamnosus (three strains), Lactobacillus paracasei (two strains), Bifidobacterium bifidum (one strain), and Bifidobacterium longum (one strain) at room temperature was investigated. The results obtained using a selected olive sample demonstrated that bifidobacteria and one strain of L. rhamnosus (Lactobacillus GG) showed a good survival rate, with a recovery of about 106 CFU g−1 after 30 days. The Lactobacillus GG population remained unvaried until the end of the experiment, while a slight decline (to about 105 CFU g−1) was observed for bifidobacteria. High viability, with more than 107 CFU g−1, was observed throughout the 3-month experiment for L. paracasei IMPC2.1. This strain, selected for its potential probiotic characteristics and for its lengthy survival on olives, was used to validate table olives as a carrier for transporting bacterial cells into the human gastrointestinal tract. L. paracasei IMPC2.1 was recovered from fecal samples in four out of five volunteers fed 10 to 15 olives per day carrying about 109 to 1010 viable cells for 10 days.  相似文献   
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A potent sigma-2 receptor ligand, known as PB28, was tritium radiolabelled and biologically evaluated. The results showed that [(3)H]PB28 and the corresponding unlabelled PB28 had superimposed pharmacodynamic properties. This radioligand appears as a potential candidate for receptor binding and in living cells assays.  相似文献   
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