142 research outputs found
Prediction of Monthly Discharge in Ungauged Catchments Under Agricultural Land Use in the Upper Ping Basin, Northern Thailand
The present paper describes a methodology proposed for surface runoff modelling in gauged and ungauged subcatchments of Northern Thailand. Gauged catchments are modelled using calibration against measured flow data, whereas streamflow in the ungauged subcatchments is simulated by a disaggregation procedure utilising measured streamflow data from a larger gauged catchment in which the ungauged subcatchment may be nested. The disaggregation technique is based on the assumption that the streamflow contribution from each subcatchment to the total catchment yield is proportional to a ratio of the catchment's area and its average slope. The Mae Chaem catchment in the Upper Ping River basin was selected as a case study for applying the approach. The model testing performed in two subcatchments, where the modelled streamflow was compared with the measured data, showed that the first pass approach algorithm provides the accuracy of 13-17% of the relative error for the monthly time step
Morphology and Genetics of the Ciscoes (Actinopterygii: Salmoniformes: Salmonidae: Coregoninae: Coregonus) from the Solovetsky Archipelago (White Sea) as a Key to Determination of the Taxonomic Position of Ciscoes in Northeastern Europe
Background: The characteristic feature of the genus <i>Coregonus</i> is the multitude of nominal species of obscure identity. The northeastern Europe is inhabited by, inter alia—the vendace, <i>Coregonus albula</i> (Linnaeus, 1758)—considered the European cisco—and the least cisco, <i>C. sardinella</i> Valenciennes, 1848—often referred to as the Siberian species. There is a large area in where the ranges of both species overlap. Using morphological- as well as genetic tools we attempted to test the working hypothesis that the <i>Coregonus</i> fish (ciscoes) inhabiting the above-mentioned transitional zone represent a single species. Materials and methods: Within 1995–2009 we collected 344 ciscoes from five lakes in Bolshoy Solovetsky Island and determined diagnostic morphological traits for the two species. For some samples, the polymorphism of the creatine kinase isoloci (<i>CK-A1,2</i>*) and the fragment of mitochondrial DNA (mtDNA) encoding the subunit 1 of NADH-dehydrogenize complex (<i>ND-1</i> fragment) was also studied. Results: According to one of the main taxonomical characteristics—the number of vertebrae—the cisco of Solovetsky Island occupies an intermediate position between <i>C. albula</i> and <i>C. sardinella</i>. The molecular markers,however, did not reveal any differences between the ciscoes of Bolshoy Solovetsky Island and the vendace found elsewhere. All specimens had the type allele of creatine kinase <i>(CK-A*100)</i> which was considered to be typical for C. albula at other locations as well as the haplotype E of mtDNA widespread in vendace populations. Conclusion: The cisco from Solovetsky Island is more similar to typical vendace. Differences in some morphological traits between Solovetsky Island populations and the vendace from elsewhere are likely to reflect adaptation to environmental conditions. Thus it appears that morphological criteria do not allow reliable differentiation between two forms of ciscoes as well as between least cisco and vendace because they are influenced by environmental conditions. We believe that the presence of populations with intermediate features is a strong argument for combining <i>C. albula</i> and <i>C. sardinella</i> into a single species (<i>C. albula</i>)
Laminin-binding integrins and their tetraspanin partners as potential antimetastatic targets
Within the integrin family of cell adhesion receptors, integrins α3β1, α6β1, α6β4 and α7β1 make up a laminin-binding subfamily. The literature is divided on the role of these laminin-binding integrins in metastasis, with different studies indicating either pro- or antimetastatic functions. The opposing roles of the laminin-binding integrins in different settings might derive in part from their unusually robust associations with tetraspanin proteins. Tetraspanins organise integrins into multiprotein complexes within discrete plasma membrane domains termed tetraspanin-enriched microdomains (TEMs). TEM association is crucial to the strikingly rapid cell migration mediated by some of the laminin-binding integrins. However, emerging data suggest that laminin-binding integrins also promote the stability of E-cadherin-based cell–cell junctions, and that tetraspanins are essential for this function as well. Thus, TEM association endows the laminin-binding integrins with both pro-invasive functions (rapid migration) and anti-invasive functions (stable cell junctions), and the composition of TEMs in different cell types might help determine the balance between these opposing activities. Unravelling the tetraspanin control mechanisms that regulate laminin-binding integrins will help to define the settings where inhibiting the function of these integrins would be helpful rather than harmful, and may create opportunities to modulate integrin activity in more sophisticated ways than simple functional blockade
Crescimento radicularde arroz daninho e cultivares de arroz irrigado em diferentes condições hídricas.
Flood Risk Assessment for Urban Drainage System in a Changing Climate Using Artificial Neural Network
Changes in rainfall patterns due to climate change are expected to have negative impact on urban drainage systems, causing increase in flow volumes entering the system. In this paper, two emission scenarios for greenhouse concentration have been used, the high (A1FI) and the low (B1). Each scenario was selected for purpose of assessing the impacts on the drainage system. An artificial neural network downscaling technique was used to obtain local-scale future rainfall from three coarse-scale GCMs. An impact assessment was then carried out using the projected local rainfall and a risk assessment methodology to understand and quantify the potential hazard from surface flooding. The case study is a selected urban drainage catchment in northwestern England. The results show that there will be potential increase in the spilling volume from manholes and surcharge in sewers, which would cause a significant number of properties to be affected by flooding
The Kelp Forest Challenge: A collaborative global movement to protect and restore 4 million hectares of kelp forests
Whole Brain Size and General Mental Ability: A Review
We review the literature on the relation between whole brain size and general mental ability (GMA) both within and between species. Among humans, in 28 samples using brain imaging techniques, the mean brain size/GMA correlation is 0.40 (N = 1,389; p < 10−10); in 59 samples using external head size measures it is 0.20 (N = 63,405; p < 10−10). In 6 samples using the method of correlated vectors to distill g, the general factor of mental ability, the mean r is 0.63. We also describe the brain size/GMA correlations with age, socioeconomic position, sex, and ancestral population groups, which also provide information about brain–behavior relationships. Finally, we examine brain size and mental ability from an evolutionary and behavior genetic perspective
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