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81.
Cottin D Brown A Oliphant A Mestre NC Ravaux J Shillito B Thatje S 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2012,162(4):357-363
We investigated the tolerance of adult specimens of the shallow-water shrimp Palaemonetes varians to sustained high hydrostatic pressure (10 MPa) across its thermal tolerance window (from 5 to 27 °C) using both behavioural (survival and activity) and molecular (hsp70 gene expression) approaches. To our knowledge, this paper reports the longest elevated hydrostatic pressure exposures ever performed on a shallow-water marine organism. Behavioural analysis showed a 100% survival rate of P. varians after 7 days at 10 MPa and 5 or 10 °C, whilst cannibalism was observed at elevated temperature (27 °C), suggesting no impairment of specific dynamic action. A significant interaction of pressure and temperature was observed for both behavioural and molecular responses. Elevated pressure was found to exacerbate the effect of temperature on the behaviour of the animals by reducing activity at low temperature and by increasing activity at high temperature. In contrast, only high pressure combined with low temperature increased the expression of hsp70 genes. We suggest that the impressive tolerance of P. varians to sustained elevated pressure may reflect the physiological capability of an ancestral species to colonise the deep sea. Our results also support the hypothesis that deep-sea colonisation may have occurred during geological periods of time when the oceanic water column was warm and vertically homogenous. 相似文献
82.
Integrative approaches to guide conservation decisions: Using genomics to define conservation units and functional corridors 下载免费PDF全文
Soraia Barbosa Frederico Mestre Thomas A. White Joana Paupério Paulo C. Alves Jeremy B. Searle 《Molecular ecology》2018,27(17):3452-3465
Climate change and increasing habitat loss greatly impact species survival, requiring range shifts, phenotypic plasticity and/or evolutionary change for long‐term persistence, which may not readily occur unaided in threatened species. Therefore, defining conservation actions requires a detailed assessment of evolutionary factors. Existing genetic diversity needs to be thoroughly evaluated and spatially mapped to define conservation units (CUs) in an evolutionary context, and we address that here. We also propose a multidisciplinary approach to determine corridors and functional connectivity between CUs by including genetic diversity in the modelling while controlling for isolation by distance and phylogeographic history. We evaluate our approach on a Near Threatened Iberian endemic rodent by analysing genotyping‐by‐sequencing (GBS) genomic data from 107 Cabrera voles (Microtus cabrerae), screening the entire species distribution to define categories of CUs and their connectivity: We defined six management units (MUs) which can be grouped into four evolutionarily significant units (ESUs) and three (putatively) adaptive units (AUs). We demonstrate that the three different categories of CU can be objectively defined using genomic data, and their characteristics and connectivity can inform conservation decision‐making. In particular, we show that connectivity of the Cabrera vole is very limited in eastern Iberia and that the pre‐Pyrenean and part of the Betic geographic nuclei contribute the most to the species genetic diversity. We argue that a multidisciplinary framework for CU definition is essential and that this framework needs a strong evolutionary basis. 相似文献
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84.
J. A. Aguilar-Alberola F. Mesquita-Joanes S. López A. Mestre J. C. Casanova J. Rueda A. Ribas 《Hydrobiologia》2012,688(1):63-73
The American red swamp crayfish Procambarus clarkii (Girard, 1852) was introduced in 1973 into the Iberian Peninsula for commercial purposes. As a result of both the expansion
from the Iberian Peninsula and, probably, further introductions in other European countries, now it is widely distributed
throughout much of Europe. The ecological impacts of this invading crayfish have received increasing attention, but nothing
is known about its symbiotic entocytherid ostracods outside the American continent. The present survey has examined more than
200 crayfishes from 12 localities distributed over a wide area of Eastern Spain. Entocytherid ostracods were extracted from
individual crayfishes and they were identified, counted, assigned to developmental instars and sexed. In all the study locations
but one, we found at least one crayfish individual infected by entocytherid ostracods and the species determined was the same
in all cases: Ankylocythere sinuosa (Rioja, 1942). The number of ostracods on individual P. clarkii varied notably in relation to crayfish size and also differed significantly among sampling sites. The crayfish size effects
on ostracod densities might be related to the amount of resources and to the crayfish age and moulting frequency affecting
ostracod distribution and population structure. In addition, the spatial variation in ostracod densities could also be related
to site-specific habitat traits and the variability of crayfish population dynamics. Our study represents the first citation
of an alien entocytherid species in Europe and demonstrates its wide distribution in the Iberian Peninsula. Further research
is needed to know the potential effects of this ostracod species on the ecology of P. clarkii and of native species, with implications on the management of this aquatic invader. 相似文献
85.
Hydroxyurea was used to study the proliferation rate of haemopoietic stem cells (CFUJ in normal mice, after irradiation or transplantation into irradiated recipients. It was demonstrated that the proliferation rate of endogenous CFUS (endo-CFU,) and exogenous CFUS (exo-CFUs) are identical. After irradiation (650 R) the surviving endo-CFUs begin to proliferate immediately. By contrast exo-CFU, transplanted into the irradiated recipient mouse (850 R), begin to proliferate only after about 30 hr. However, injection of isoproterenol (which stimulates adenyl cyclase) or dibutyryl cyclic adenosine 3′,5′-monophosphate shortly after marrow cell graft, triggers the transplanted CFUS into cell cycle as shown by an almost immediately increased sensitivity to hydroxyurea. Isoproterenol is capable of inducing DNA synthesis also in stem cells of normal mice but it takes about 20 hr before CFU, become to be increasingly sensitive to hydroxyurea. 相似文献
86.
R. ROMERO DEL CASTILLO J. VALERO F. CASAÑAS E. COSTELL 《Journal of sensory studies》2008,23(3):303-319
The inclusion of dry beans in diets has clear health benefits. However, consumers in developed countries mainly choose beans for their sensory qualities, especially for their texture. This article describes the constitution, training and validation of a panel of judges to evaluate the texture of dry beans. The judges were trained in the perception of different textures, analyzed a wide range of beans and selected seed-coat roughness, seed-coat perceptibility and creaminess/mealiness of the cotyledon as the main attributes to be scored. After training, the panel was capable of discriminating between different varieties of beans and even between beans of the same variety grown at different locations. The analysis of the behavior of the panel in a standard tasting session 2 years after its formation showed that periodic inclusion of samples from the extremes of the scales for the attributes during tasting sessions was sufficient to keep the panel trained.
This article could serve as a guide for the training of sensory panels to evaluate the texture of dry beans. It describes the selection of the attributes on which the analysis is based, references for the extreme values of the attributes and how to train the panel. It also provides a practical example of the analysis of the behavior of the panel some time after training. 相似文献
PRACTICAL APPLICATIONS
This article could serve as a guide for the training of sensory panels to evaluate the texture of dry beans. It describes the selection of the attributes on which the analysis is based, references for the extreme values of the attributes and how to train the panel. It also provides a practical example of the analysis of the behavior of the panel some time after training. 相似文献
87.
88.
Natalia B. Arancibia Mariana Solans M. Cecilia Mestre Eugenia E. Chaia 《Symbiosis (Philadelphia, Pa.)》2018,76(2):129-137
Large areas in the extra-Andean region in the forest - steppe ecotone in “Northwestern Argentinean Patagonia” have been replaced by plantations of the exotic conifer Pinus ponderosa which modify soils physical and chemical factors and alter the biodiversity. Considering that in the region occur saprophytic soilborne actinobacteria that play important role as the fixation of atmospheric nitrogen (N2) in symbiosis with native plant species and the production of bioactive molecules in plants rhizosphere, we aimed to study the effect of the plantation on the abundance of the N2 fixer Frankia and on the genus diversity of cultivable rhizospheric actinobacteria. The study was performed with soils of six paired sites with pine plantations and natural neighbor areas (including steppes or shrublands). Abundance of infective Frankia was estimated by evaluating the nodulation capacity of soils, through a plant bioassay using Ochetophila trinervis as trap plant. Isolation trials for saprophytic actinobacteria were performed by applying chemotactic and successive soils dilutions methods. We concluded that P. ponderosa afforestation affect soil actinobacteria. This was mainly evidenced by a decrease in the Frankia nodulation capacity in O. trinervis, which was related to plantation age, to lower soil carbon and nitrogen content, higher available phosphorus, and to a slight decrease in soils pH. Pine plantation influence on the cultivable saprophytic actinobacteria was less clear. The study highlights the importance of soils as source of Frankia and rhizospheric actinobacteria in relation to disturbance caused by pine plantation in natural environments with native actinorhizal plant species. 相似文献
89.
90.
Ga?lle Le Henanff Thierry Heitz Pere Mestre Jer?me Mutterer Bernard Walter Julie Chong 《BMC plant biology》2009,9(1):54