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991.
992.
Maria Isabel Ferreira Steve Green Nuno Conceição José-Enrique Fernández 《Plant and Soil》2018,425(1-2):21-41
Aims
In this study on hydraulic redistribution (HR) in roots, we aimed to use the calibrated average-gradient (CAG) heat-pulse method, the novelty being the use of a much narrower averaging window for the signal analysis, in order to achieve a more linear calibration curve, allowing the HR quantification.Methods
The study was conducted in 12 large roots of a rain-fed olive orchard, for 6 months without significant rain, when the predawn leaf water potential decreased to ?2.4 MPa, and immediately following the first autumn rains.Results
Detailed numerical modelling of the CAG method allowed verification of the response of the measurement system to a range of drivers, improving the linear range of the calibration response function, which has remained stable over the observations period. On average, reverse flow was observed during 30% of the summer nights and, in a conservative estimate, it increased to about 5% of total daily root flow before first autumn rain.Conclusions
Reverse flow accounted on average for 2.6% of the total daily root flow, enabling upper roots to stay active during the very dry late-summer period. In qualitative terms, our results confirm the CAG method as a reliable tool to identify reverse flow and quantify HR when it occurs.993.
Pharmacologic treatment of donor cells induced to have a Warburg effect‐like metabolism does not alter embryonic development in vitro or survival during early gestation when used in somatic cell nuclear transfer in pigs 下载免费PDF全文
994.
995.
Attachment theory is a useful lens through which to examine both perceptions and selection of companion animals. Study 1 compared perceptions of dogs and cats, and found that dogs were perceived as having more positive relationship qualities and secure attachment-related characteristics, whereas cats were perceived as having more negative relationship qualities and avoidant attachment-related characteristics. In addition, people perceived relationships with dogs to involve less avoidance and less anxiety relative to relationships with people. In study 2, which built on the findings of study 1, attachment avoidance was negatively associated with wanting to own a pet, whereas attachment anxiety was positive associated with wanting to own a pet. These attachment dimensions were not associated with wanting to own a dog, but lower avoidance and higher anxiety were associated with wanting to own a cat. Study 3 was a longitudinal study of SPCA-type shelter visitors (510 participants, with 169 reporting a recent pet adoption). Lower attachment anxiety predicted recently adopting a dog rather than a cat, though neither anxiety nor avoidance predicted adopting a cat. Individuals who wanted a pet in order to facilitate human relationships were more likely to adopt a dog than a cat. Those high in attachment avoidance reported turning to their pet as a replacement for human companionship, and those high in attachment anxiety reported feeling more concern about their pets requiring more attention. Attachment anxiety and avoidance may influence the decision whether or not to adopt a pet, as well as the motivation underlying the adoption choice. Attachment also may influence the type of pet chosen (i.e., dog versus cat). In addition, attachment may influence the nature of the human–animal relationship, such as the time spent together, and the security felt regarding the relationship. 相似文献
996.
D. S. Green L. Johnson-Ulrich H. E. Couraud K. E. Holekamp 《Biodiversity and Conservation》2018,27(4):871-889
Large carnivore populations are declining worldwide due to direct and indirect conflicts with humans. Protected areas are critical for conserving large carnivores, but increasing human-wildlife conflict, tourism, and human population growth near these sanctuaries may have negative effects on the carnivores within sanctuary borders. Our goals were to investigate how anthropogenic disturbance along the edge of the Masai Mara National Reserve, Kenya, influences the demography and space-use of two large carnivore species that engage in intense interspecific competition. Here we document, in one disturbed region of the Reserve, a rapid increase in the population size of one large predator, the spotted hyena (Crocuta crocuta), but a striking concurrent decline in numbers of another, the African lion (Panthera leo). Anthropogenic disturbances negatively affected lion populations, and decreasing lion numbers appear to have a positive effect on hyena populations, indicated here by an increase in juvenile survivorship. We also saw an increase in the number of livestock consumed by hyenas. Our results suggest human population growth and indirect effects of human activity along Reserve boundaries may be effecting a trophic cascade inside the Reserve itself. These results indicate both top-down and bottom-up processes are causing a shift in the carnivore community, and a major disruption of guild structure, inside the boundaries of one of the most spectacular protected areas in Africa. 相似文献
997.
Adrian Munguia-Vega Alison L. Green Alvin N. Suarez-Castillo Maria Jose Espinosa-Romero Octavio Aburto-Oropeza Andrés M. Cisneros-Montemayor Gabriela Cruz-Piñón Gustavo Danemann Alfredo Giron-Nava Ollin Gonzalez-Cuellar Cristina Lasch Maria del Mar Mancha-Cisneros Silvio Guido Marinone Marcia Moreno-Báez Hem-Nalini Morzaria-Luna Héctor Reyes-Bonilla Jorge Torre Peggy Turk-Boyer Mariana Walther Amy Hudson Weaver 《Reviews in Fish Biology and Fisheries》2018,28(4):749-776
No-take marine reserves can be powerful management tools, but only if they are well designed and effectively managed. We review how ecological guidelines for improving marine reserve design can be adapted based on an area’s unique evolutionary, oceanic, and ecological characteristics in the Gulf of California, Mexico. We provide ecological guidelines to maximize benefits for fisheries management, biodiversity conservation and climate change adaptation. These guidelines include: representing 30% of each major habitat (and multiple examples of each) in marine reserves within each of three biogeographic subregions; protecting critical areas in the life cycle of focal species (spawning and nursery areas) and sites with unique biodiversity; and establishing reserves in areas where local threats can be managed effectively. Given that strong, asymmetric oceanic currents reverse direction twice a year, to maximize connectivity on an ecological time scale, reserves should be spaced less than 50–200 km apart depending on the planktonic larval duration of target species; and reserves should be located upstream of fishing sites, taking the reproductive timing of focal species in consideration. Reserves should be established for the long term, preferably permanently, since full recovery of all fisheries species is likely to take?>?25 years. Reserve size should be based on movement patterns of focal species, although marine reserves?>?10 km long are likely to protect?~?80% of fish species. Since climate change will affect species’ geographic range, larval duration, growth, reproduction, abundance, and distribution of key recruitment habitats, these guidelines may require further modifications to maintain ecosystem function in the future. 相似文献
998.
Huai Gao Craig Marhefka Marc D. Jacobs Jingrong Cao Upul K. Bandarage Jeremy Green 《Bioorganic & medicinal chemistry letters》2018,28(15):2616-2621
Solubilizing groups have been frequently appended to kinase inhibitor drug molecules when solubility is insufficient for pharmaceutical development. Such groups are usually located at substitution sites that have minimal impact on target activity. In this report we describe the incorporation of solubilizing groups in a class of Rho kinase (ROCK) inhibitors that not only confer improved solubility, but also enhance target potency and selectivity against a closely related kinase, PKA. 相似文献
999.
Gurleen K. Samra Irakli Intskirveli Anitha P. Govind Christopher Liang Ronit Lazar William N. Green Raju Metherate Jogeshwar Mukherjee 《Bioorganic & medicinal chemistry letters》2018,28(3):371-377
Nicotinic acetylcholine α4β21 receptors (nAChRs) are implicated in various neurodegenerative diseases and smoking addiction. Imaging of brain high-affinity α4β21 nAChRs at the cellular and subcellular levels would greatly enhance our understanding of their functional role. Since better resolution could be achieved with fluorescent probes, using our previously developed positron emission tomography (PET) imaging agent [18F]nifrolidine, we report here design, synthesis and evaluation of two fluorescent probes, nifrodansyl and nifrofam for imaging α4β21 nAChRs. The nifrodansyl and nifrofam exhibited nanomolar affinities for the α4β21 nAChRs in [3H]cytisine-radiolabeled rat brain slices. Nifrofam labeling was observed in α4β21 nAChR-expressing HEK cells and was upregulated by nicotine exposure. Nifrofam co-labeled cell-surface α4β21 nAChRs, labeled with antibodies specific for a β2 subunit extracellular epitope indicating that nifrofam labels α4β21 nAChR high-affinity binding sites. Mouse brain slices exhibited discrete binding of nifrofam in the auditory cortex showing promise for examining cellular distribution of α4β21 nAChRs in brain regions. 相似文献
1000.
Duncan Mortimer Marije Bosch Joanne E. Mckenzie Simon Turner Marisa Chau Jennie L. Ponsford Jonathan C. Knott Russell L. Gruen Sally E. Green 《Implementation science : IS》2018,13(1):147