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101.
During the Mesozoic, one of the most significant evolutionary processes was the secondary adaptation of tetrapods to life in water. Several non-related lineages invaded from the terrestrial realms and from the oceans of the entire world. Among these lineages, ichthyosaurs were particularly successful. Advance parvipelvian ichthyosaurs were the first tetrapods to evolve a fish-shaped body profile. The deep skeletal modifications of their bodies, as well as their biology, depict advance ichthyosaurs as the paradigm of secondary adaptation of reptiles to marine life. Functional inferences point to them as off-shore cruising forms, similar to a living tuna, and some of them were capable of deep diving. Bone histology of some genera such as Temnodontosaurus, Stenopterygius, Ichthyosaurus, and Caypullisaurus, characterized by overall cancellous bone, is consistent with the idea of a fish-shaped ichthyosaurs as fast and far cruisers. Here, we provide histological examination of the ribs of the Middle Jurassic parvipelvian Mollesaurus. Contrasting with the bone histology of other parvipelvian, Mollesaurus ribs are characterized by a compact and thick cortex. Our data indicate that the rib cage was heavy and suggest that not all advanced ichthyosaurs were fast cruisers. The compact and dense ribs in these parvipelvian show that advance ichthyosaurs were ecologically more diverse than previously thought and that the lightening of the skeleton reversed, as also occurred in the evolution of cetacean, at least once along the evolutionary history of ichthyosaurs.  相似文献   
102.
The application of plant essential oils (EOs) (hyssop and marjoram) was evaluated for inactivation of non-enveloped viruses using murine norovirus and human adenovirus as models. No significant reduction of virus titres (TCID50) was observed when EOs were used at different temperatures and times.  相似文献   
103.
Journal of Polymers and the Environment - High-amylose maize starch (AS) was modified by graft copolymerization with sodium acid maleate and disodium maleate, using the KMnO4-NaHSO3 redox system,...  相似文献   
104.
Journal of Polymers and the Environment - The search for a straightforward technology for post-consumer poly(ethylene terephthalate) (PC-PET) degradation is essential to develop a circular economy....  相似文献   
105.
106.
This study examines stress and mood outcomes in community volunteers who undertook one week's worth of post‐disaster relief work in L'Aquila, Italy, which had been hit by an earthquake four months earlier. The study team obtained pre‐ and post‐relief work data from 130 volunteers involved in activities such as preparing food for the displaced, cleaning the camps and distributing clean linen. The Perceived Stress Scale, the State‐Trait Anxiety Inventory and the Profile of Mood States were administered at the start and at the end of the aid activities. Psychopathological symptoms and empathy were assessed in the beginning, using the Symptom Checklist 90 Revised and the Interpersonal Reactivity Index, respectively. The results show that, following the assistance work, volunteers displayed decreases in perceived stress, general distress, anxiety and anger, as well as increases in positive emotions. The empathy facets empathic concern and personal distress showed different patterns in modulating the post‐disaster relief work adaptation for some of the mood outcomes.  相似文献   
107.
Several factors such as smoking habits, diet, occupational, and environmental exposure to chemical carcinogens influence the overall level of DNA damage. In 69 healthy adult volunteers’ polymorphisms of glutathione S-transferase (GST), an enzyme which participates in the metabolism of a broad range of carcinogens and endogenous compounds were determined. The level of DNA damage was assessed by comet assay and classified according to GSTT1/M1 genotype and smoking habits. GSTM1 null genotype was recognized in 48% of studied subjects and GSTT1 null genotype in only two cases (3%). In subjects carrying GSTT1/M1 alleles a significantly lower degree of DNA damage, determined as % DNA in the comet's tail, than in null individuals was noted. However, the results obtained did not indicate that in studied subjects an elevated endogenous level of DNA damage may be significantly related to smoking habits.  相似文献   
108.
Adults vary in their generosity in provisioning the young and their sensitivity to the need of the young. Do the young modulate their behaviour so as to specifically target more high-provisioning adults? This is especially likely in situations with mobile, nutritionally dependent young. We studied cooperatively breeding meerkats Suricata suricatta, in which pups beg to parents and other adults in the group. We found that the young begged differently when next to different adults and that they are consistent in how they beg when next to each adult. Pups next to adults that provision at high rates beg at higher rates and spend longer with them, and these adults are generally more sensitive to increases in begging rate. Such behaviour has adaptive benefits to offspring in terms of increased likelihood of being fed. However, offspring do not appear to be actively seeking out high-provisioning adults or increasing their begging behaviour when they encounter one. Pups did not appear to actively discriminate between adults in their association or begging behaviour. We suggest instead that the relationship between an adult's relative contribution to pup feeding and the behaviour of its accompanying pup is driven by adult behaviour, with responsive adults that feed pups at a relatively higher rate preferentially associating with fast-begging hungry pups.  相似文献   
109.
Loggerhead turtles nesting in the Mediterranean Sea exhibit remarkable genetic structuring. This paper tests the hypothesis that young loggerhead turtles from different rookeries do not distribute homogeneously among the major Mediterranean foraging grounds, due to a complex pattern of surface currents. We extracted long fragments of mitochondrial DNA from 275 stranded or bycaught juvenile turtles from six foraging grounds (Catalano-Balearic Sea, Algerian basin, Tyrrhenian Sea, Adriatic Sea, northern Ionian Sea and southern Levantine Sea). We used a Bayesian mixed-stock analysis to estimate the contributions from rookeries in the Mediterranean, the North-west Atlantic and Cape Verde to the studied foraging grounds. Differences were found in the relative contribution of juvenile turtles of Atlantic and Mediterranean origin to each foraging ground. A decreasing proportion of Atlantic juveniles was detected along the main surface current entering the Mediterranean, with a high prevalence of turtles from eastern Florida in the Algerian basin and lower numbers elsewhere. In regard to the turtles of Mediterranean origin, juveniles from Libya prevailed in central and western Mediterranean foraging grounds other than the Algerian basin. Conversely, the Adriatic Sea was characterised by a large presence of individuals from western Greece, while the southern Levantine Sea was inhabited by a heterogeneous mix of turtles from the eastern Mediterranean rookeries (Turkey, Lebanon and Israel). Overall, the distribution of juveniles may be related to surface circulation patterns in the Mediterranean and suggests that fisheries might have differential effects on each population depending on the overlap degree between foraging and fishing grounds.  相似文献   
110.
Knowing the trophic ecology of marine predators is essential to develop an understanding of their ecological role in ecosystems. Research conducted on deep-sea and threatened shark species is limited. Here, by combining analyses of individual stomach contents and stable isotope values, we examined the trophic ecology (dietary composition and trophic position) of the kitefin shark Dalatias licha, a deep-sea shark considered as near threatened globally and as data deficient in the Mediterranean Sea. Results revealed the importance of small sharks in the diet of the kitefin shark at short- and long-term scales, although fin-fish, crustaceans and cephalopods were also found. Predation on sharks reveals the high trophic position of the kitefin shark within the food web of the western Mediterranean Sea. Stable isotope values from liver and muscle tissues confirmed our results from stomach content analysis and the high trophic position.  相似文献   
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