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961.
Sabrina L. Caetano Guilherme J. M. Rosa Rodrigo P. Savegnago Salvador B. Ramos Priscila A. Bernardes Luiz A. F. Bezerra Raysildo B. Lôbo Claudia C. P. de Paz Danísio Prado Munari 《Journal of applied genetics》2017,58(1):103-109
The aim of this study was to estimate heritability and predict breeding values for longevity among cows in herds of Nellore breed, considering the trait cow’s age at last calving (ALC), by means of survival analysis methodology. The records of 11,791 animals from 22 farms were used. The variable ALC has been used by a criterion that made it possible to include cows not only at their first calving but also at their ninth calving. The criterion used was the difference between the date of each cow’s last calving and the date of the last calving on each farm. If this difference was greater than 36 months, the cow was considered to have failed and uncensored. If not, this cow was censored, thus indicating that future calving remained possible for this cow. The survival model used for the analyses was the proportional hazards model, and the base risk was given by a Weibull distribution. The heritability estimate obtained was equal to 0.25. It was found that the ALC variable had the capacity to respond to selection for the purpose of increasing the longevity of the cows in the herds. 相似文献
962.
Adaptive and non‐adaptive evolution of trait means and genetic trait correlations for herbivory resistance and performance in an invasive plant 下载免费PDF全文
Karin Schrieber Sabrina Wolf Catherina Wypior Diana Höhlig Isabell Hensen Susanne Lachmuth 《Oikos》2017,126(4):572-582
The EICA‐hypothesis predicts that invading plants adapt to their novel environment by evolving increased performance and reduced resistance in response to the release from natural enemies, and assumes a resource allocation tradeoff among both trait groups as mechanistic basis of this evolutionary change. Using the plant Silene latifolia as a study system, we tested these predictions by investigating whether 1) invasive populations evolved lower resistance and higher performance, 2) this evolutionary change is indeed adaptive, and 3) there is a negative genetic correlation between performance and resistance (i.e. a tradeoff) in native and introduced individuals. Moreover, we sampled eight native and eight invasive populations and determined their population co‐ancestry based on neutral SSR‐markers. We performed controlled crossings to produce five sib‐groups per population and exposed them to increased and reduced levels of enemy attack in a full‐factorial experiment to estimate performance and resistance. With these data, we performed trait‐by‐trait comparisons between ranges with ‘animal models’ that account for population co‐ancestry to quantify the amount of variance in traits explained by non‐adaptive versus adaptive evolution. Moreover, we tested for genetic correlations among performance and resistance traits within sib‐groups. We found significant reductions in resistance and increases in performance in invasive versus native populations, which could largely be attributed to adaptive evolution. While we detected a non‐significant trend towards negative genetic performance × resistance correlations in native populations, invasive populations exhibited both significant and non‐significant positive correlations. In summary, these results do not support a shift of performance and resistance trait values along a tradeoff line in response to enemy release, as predicted by EICA. They rather suggest that the independent evolution of both traits is not constrained by a tradeoff, and that various selective agents (including resource availability) interact in shaping both traits and in weakening negative genetic correlations in the invaded habitat. 相似文献
963.
Social insects exhibit complex learning and memory mechanisms while foraging. Vespula germanica (Fab.) (Hymenoptera: Vespidae) is an invasive social wasp that frequently forages on undepleted food sources, making several flights between the resource and the nest. Previous studies have shown that during this relocating behavior, wasps learn to associate food with a certain site, and can recall this association 1 h later. In this work, we evaluated whether this wasp species is capable of retrieving an established association after 24 h. For this purpose, we trained free flying individuals to collect proteinaceous food from an experimental plate (feeder) located in an experimental array. A total of 150 individuals were allowed 2, 4, or 8 visits. After the training phase, the array was removed and set up again 24 h later, but this time a second baited plate was placed opposite to the first. After 24 h we recorded the rate of wasps that returned to the experimental area and those which collected food from the previously learned feeding station or the nonlearned one. During the testing phase, we observed that a low rate of wasps trained with 2 collecting visits returned to the experimental area (22%), whereas the rate of returning wasps trained with 4 or 8 collecting visits was higher (51% and 41%, respectively). Moreover, wasps trained with 8 feeding visits collected food from the previously learned feeding station at a higher rate than those that did from the nonlearned one. In contrast, wasps trained 2 or 4 times chose both feeding stations at a similar rate. Thus, significantly more wasps returned to the previously learned feeding station after 8 repeated foraging flights but not after only 2 or 4 visits. This is the first report that demonstrates the existence of long‐term spatial memory in V. germanica wasps. 相似文献
964.
Resource partitioning facilitates coexistence in sympatric cetaceans in the California Current 下载免费PDF全文
Sabrina Fossette Briana Abrahms Elliott L. Hazen Steven J. Bograd Kelly M. Zilliacus John Calambokidis Julia A. Burrows Jeremy A. Goldbogen James T. Harvey Baldo Marinovic Bernie Tershy Donald A. Croll 《Ecology and evolution》2017,7(21):9085-9097
Resource partitioning is an important process driving habitat use and foraging strategies in sympatric species that potentially compete. Differences in foraging behavior are hypothesized to contribute to species coexistence by facilitating resource partitioning, but little is known on the multiple mechanisms for partitioning that may occur simultaneously. Studies are further limited in the marine environment, where the spatial and temporal distribution of resources is highly dynamic and subsequently difficult to quantify. We investigated potential pathways by which foraging behavior may facilitate resource partitioning in two of the largest co‐occurring and closely related species on Earth, blue (Balaenoptera musculus) and humpback (Megaptera novaeangliae) whales. We integrated multiple long‐term datasets (line‐transect surveys, whale‐watching records, net sampling, stable isotope analysis, and remote‐sensing of oceanographic parameters) to compare the diet, phenology, and distribution of the two species during their foraging periods in the highly productive waters of Monterey Bay, California, USA within the California Current Ecosystem. Our long‐term study reveals that blue and humpback whales likely facilitate sympatry by partitioning their foraging along three axes: trophic, temporal, and spatial. Blue whales were specialists foraging on krill, predictably targeting a seasonal peak in krill abundance, were present in the bay for an average of 4.7 months, and were spatially restricted at the continental shelf break. In contrast, humpback whales were generalists apparently feeding on a mixed diet of krill and fishes depending on relative abundances, were present in the bay for a more extended period (average of 6.6 months), and had a broader spatial distribution at the shelf break and inshore. Ultimately, competition for common resources can lead to behavioral, morphological, and physiological character displacement between sympatric species. Understanding the mechanisms for species coexistence is both fundamental to maintaining biodiverse ecosystems, and provides insight into the evolutionary drivers of morphological differences in closely related species. 相似文献
965.
Prior Exercise Training Prevent Hyperglycemia in STZ Mice by Increasing Hepatic Glycogen and Mitochondrial Function on Skeletal Muscle 下载免费PDF全文
966.
Cannabidiol Activates Neuronal Precursor Genes in Human Gingival Mesenchymal Stromal Cells 下载免费PDF全文
967.
Katharina Hirschenhauser Yasmine Meichel Sabrina Schmalzer Andrea M. Beetz 《Anthrozo?s》2017,30(3):441-456
Generally, children love their pets. However, a deeper insight into the beneficial effects of pets on the physical, psychological, and social wellbeing and development of children is needed. This study investigated whether children have more intense relationships with animals which are behaviorally similar to humans (according to the scala naturae), and whether the relationship patterns between 11- to 14-year-old children (n = 72) and their pets differ from those in prepubescent children, between 6 and 10 years of age (n = 84). We also investigated whether pet-relationship quality is associated with children’s age, gender, and number of siblings. Data about individual bonding type and attachment quality between the children and their pet were collected using a questionnaire. The results indicate that the younger children’s relationships clearly co-varied with taxonomic order of the pet. In contrast, 11- to 14-year-old children reported similarly high scores of attachment with their mouse or iguana as with their dog or cat, and the relationship patterns did not co-vary with taxonomic order. Gender effects on relationship quality were found in both age groups; especially girls reported intense relationships with their pets. In addition to gender, children without siblings had stronger attachment to their pet than children who had siblings. Our data suggest that young children develop high-quality relationships with pets, particularly those which are taxonomically closely related, such as dogs and cats, and less so with other pet species, such as birds or fish. Older children were also able to strongly attach to other pet species. We argue that mental relationship representations change during puberty and that older (11- to 14-year-old) children may no longer make attachments to pets based on them being behaviorally similar to people. 相似文献
968.
Marco Mengarelli Sabrina Neugebauer Matthias Finkbeiner Michele Germani Patrizia Buttol Francesca Reale 《The International Journal of Life Cycle Assessment》2017,22(8):1288-1301
Purpose
End-of-life (EoL) modelling in life cycle assessment has already been broadly discussed within several studies. However, no consensus has been achieved on how to model recycling in LCA, even though several approaches have been developed. Within this paper, results arising from the application of two new EoL formulas, the product environmental footprint (PEF) and the multi-recycling-approach (MRA) ones, are compared and discussed. Both formulas consider multiple EoL scenarios such as recycling, incineration and landfill.Methods
The PEF formula has been developed within the PEF programme whose intent is to define a harmonized methodology to evaluate the environmental performance of products. The formula is based on a 50:50 allocation approach, as burdens and benefits associated with recycling are accounted for a 50% rate. The MRA formula has been developed to change focus from products to materials. Recycling cycles and material losses over time are considered with reference to material pools. Allocation between systems is no longer needed, as the actual number of potential life cycles for a certain material is included in the calculation. Both the approaches have been tested within two case studies.Results and discussion
Methodological differences could thereof be determined, as well as applicability concerns, due to the type of data required for each formula. As far as the environmental performance is concerned, impacts delivered by MRA are lower than those delivered by PEF for aluminium, while the opposite happens for plastic and rubber due to the higher share of energy recovery accounted in PEF formula. Stainless steel impacts are almost the same.Conclusions and recommendations
The application of the two formulas provides some inputs for the EoL dilemma in LCA. The use of a wider perspective, better reflecting material properties all over the material life cycle, is of substantial importance to properly represent recycling situations. In MRA, such properties are treated and less data are required compared to the PEF formula. On the contrary, the PEF model better accommodates the modelling of products whose materials, at end of life, can undertake the route of recycling or recovery (or landfill), depending on country-specific EoL management practices. However, its application requires more data.969.
970.
Zambarlal Bhujabal Åsa B Birgisdottir Eva Sjøttem Hanne B Brenne Aud Øvervatn Sabrina Habisov Vladimir Kirkin Trond Lamark Terje Johansen 《EMBO reports》2017,18(6):947-961
Mitophagy, the selective removal of damaged or excess mitochondria by autophagy, is an important process in cellular homeostasis. The outer mitochondrial membrane (OMM) proteins NIX, BNIP3, FUNDC1, and Bcl2‐L13 recruit ATG8 proteins (LC3/GABARAP) to mitochondria during mitophagy. FKBP8 (also known as FKBP38), a unique member of the FK506‐binding protein (FKBP) family, is similarly anchored in the OMM and acts as a multifunctional adaptor with anti‐apoptotic activity. In a yeast two‐hybrid screen, we identified FKBP8 as an ATG8‐interacting protein. Here, we map an N‐terminal LC3‐interacting region (LIR) motif in FKBP8 that binds strongly to LC3A both in vitro and in vivo. FKBP8 efficiently recruits lipidated LC3A to damaged mitochondria in a LIR‐dependent manner. The mitophagy receptors BNIP3 and NIX in contrast are unable to mediate an efficient recruitment of LC3A even after mitochondrial damage. Co‐expression of FKBP8 with LC3A profoundly induces Parkin‐independent mitophagy. Strikingly, even when acting as a mitophagy receptor, FKBP8 avoids degradation by escaping from mitochondria. In summary, this study identifies novel roles for FKBP8 and LC3A, which act together to induce mitophagy. 相似文献