998 resultados para south-south cooperation


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Estimation of the dimensions of fluvial geobodies from core data is a notoriously difficult problem in reservoir modeling. To try and improve such estimates and, hence, reduce uncertainty in geomodels, data on dunes, unit bars, cross-bar channels, and compound bars and their associated deposits are presented herein from the sand-bed braided South Saskatchewan River, Canada. These data are used to test models that relate the scale of the formative bed forms to the dimensions of the preserved deposits and, therefore, provide an insight as to how such deposits may be preserved over geologic time. The preservation of bed-form geometry is quantified by comparing the Alluvial architecture above and below the maximum erosion depth of the modem channel deposits. This comparison shows that there is no significant difference in the mean set thickness of dune cross-strata above and below the basal erosion surface of the contemporary channel, thus suggesting that dimensional relationships between dune deposits and the formative bed-form dimensions are likely to be valid from both recent and older deposits. The data show that estimates of mean bankfull flow depth derived from dune, unit bar, and cross-bar channel deposits are all very similar. Thus, the use of all these metrics together can provide a useful check that all components and scales of the alluvial architecture have been identified correctly when building reservoir models. The data also highlight several practical issues with identifying and applying data relating to cross-strata. For example, the deposits of unit bars were found to be severely truncated in length and width, with only approximately 10% of the mean bar-form length remaining, and thus making identification in section difficult. For similar reasons, the deposits of compound bars were found to be especially difficult to recognize, and hence, estimates of channel depth based on this method may be problematic. Where only core data are available (i.e., no outcrop data exist), formative flow depths are suggested to be best reconstructed using cross-strata formed by dunes. However, theoretical relationships between the distribution of set thicknesses and formative dune height are found to result in slight overestimates of the latter and, hence, mean bankfull flow depths derived from these measurements. This article illustrates that the preservation of fluvial cross-strata and, thus, the paleohydraulic inferences that can be drawn from them, are a function of the ratio of the size and migration rate of bed forms and the time scale of aggradation and channel migration. These factors must thus be considered when deciding on appropriate length:thickness ratios for the purposes of object-based modeling in reservoir characterization.

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AimOur aim was to understand the interplay of heterogeneous climatic and spatial landscapes in shaping the distribution of nuclear microsatellite variation in burrowing parrots, Cyanoliseus patagonus. Given the marked phenotypic differences between populations of burrowing parrots we hypothesized an important role of geographical as well climatic heterogeneity in the population structure of this species. LocationSouthern South America. MethodsWe applied a landscape genetics approach to investigate the explicit patterns of genetic spatial autocorrelation based on both geography and climate using spatial principal component analysis (sPCA). This necessitated a novel statistical estimation of the species climatic landscape, considering temperature- and precipitation-based variables separately to evaluate their weight in shaping the distribution of genetic variation in our model system. ResultsGeographical and climatic heterogeneity successfully explained molecular variance in burrowing parrots. sPCA divided the species distribution into two main areas, Patagonia and the pre-Andes, which were connected by an area of geographical and climatic transition. Moreover, sPCA revealed cryptic and conservation-relevant genetic structure: the pre-Andean populations and the transition localities were each divided into two groups, each management units for conservation. Main conclusionssPCA, a method originally developed for spatial genetics, allowed us to unravel the genetic structure related to spatial and climatic landscapes and to visualize these patterns in landscape space. These novel climatic inferences underscore the importance of our modified sPCA approach in revealing how climatic variables can drive cryptic patterns of genetic structure, making the approach potentially useful in the study of any species distributed over a climatically heterogeneous landscape.

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This bachelor's thesis studies calendar anomalies in stock returns in five South American countries including Argentina, Brazil, Chile and Mexico. The analysis in done using regression analysis and the OLS- method.

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Spatio-temporal variability in settlement and recruitment, high mortality during the first life-history stages, and selection may determine the genetic structure of cohorts of long-lived marine invertebrates at small scales. We conducted a spatial and temporal analysis of the common Mediterranean Sea urchin Paracentrotus lividus to determine the genetic structure of cohorts at different scales. In Tossa de Mar (NW Mediterranean), recruitment was followed over 5 consecutive springs (2006-2010). In spring 2008, recruits and two-year-old individuals were collected at 6 locations along East and South Iberian coasts separated from 200 to over 1,100 km. All cohorts presented a high genetic diversity based on a fragment of mtCOI. Our results showed a marked genetic homogeneity in the temporal monitoring and a low degree of spatial structure in 2006. In 2008, coupled with an abnormality in the usual circulation patterns in the area, the genetic structure of the southern populations studied changed markedly, with arrival of many private haplotypes. This fact highlights the importance of point events in renewing the genetic makeup of populations, which can only be detected through analysis of the cohort structure coupling temporal and spatial perspectives.

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A network of twenty stakes was set up on Johnsons Glacier in order to determine its dynamics. During the austral summers from 1994-95 to 1997-98, we estimated surface velocities, mass balances and ice thickness variations. Horizontal velocity increased dow nstream from 1 m a- 1 near the ice divides to 40 m a- 1 near the ice terminus. The accumulation zone showed low accumulation rates (maximum of 0,6 m a- 1 (ice)), whereas in the lower part of the glacier, ablation rates were 4,3 m a- 1 (ice). Over the 3-year study period, both in the accumulation and ablation zones, we detected a reduction in the ice surface level ranging from 2 to 10 m from the annual ve rt ical velocities and ice-thinning data, the mass balance was obtained and compared with the mass balance field values, resulting in similar estimates. Flux values were calculated using cross-section data and horizontal velocities, and compared with the results obtained by means of mass balance and ice thinning data using the continuity equation. The two methods gave similar results.

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Tutkielma tarkastelee vapaa alue konseptia osana yritysten kansainvälistä toimitusketjua. Tarkoituksena on löytää keinoja, millä tavoin vapaa alueen houkuttelevuutta voidaan lisätä yritysten näkökulmasta ja millaista liiketoimintaa yritysten on vapaa alueella mahdollista harjoittaa. Tutkielmassa etsitään tekijöitä, jotka vaikuttavat vapaa alueen menestykseen ja jotka voisivat olla sovellettavissa Kaakkois-Suomen ja Venäjän raja-alueelle ottaen huomioon vallitsevat olosuhteet ja lainsäädäntö rajoittavina tekijöinä. Menestystekijöitä ja liiketoimintamalleja haetaan tutkimalla ja analysoimalla lyhyesti muutamia olemassa olevia ja toimivia vapaa alueita. EU tullilain harmonisointi ja kansainvälisen kaupan vapautuminen vähentää vapaa alueen perinteistä merkitystä tullivapaana alueena. Sen sijaan vapaa alueet toimivat yhä enenevissä määrin logistisina keskuksina kansainvälisessä kaupassa ja tarjoavat palveluita, joiden avulla yritykset voivat parantaa logistista kilpailukykyään. Verkostoituminen, satelliitti-ratkaisut ja yhteistoiminta ovat keinoja, millä Kaakkois-Suomen alueen eri logistiikkapalvelujen tarjoajat voivat parantaa suorituskykyään ja joustavuutta kansainvälisessä toimitusketjussa.

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During a study of the helminth fauna of 1,643 rodents trapped along the Mekong River (Thailand, LaoPeople"s Democratic Republic and Cambodia) in 2008-2011, the spirurid nematode Physaloptera ngoci Le-Van-Hoa,1961 was recovered with an overall prevalence of 2.8%. Based on the original description, it was identified in nine of 23 different Murinae host species and is here reported for the first time from these three countries. A scanning electron microscopy study provides additional morphological data.

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[cat] El comerç internacional en béns agrícoles té el potencial d'accelerar la transformació estructural dels països amb baixa productivitat agrícola perquè els dóna la possiblitat d'importar aliments. L'objectiu d'aquest article és estudiar l'importància del comerç internacional en aquest context a través dels exemples de Corea del Sud i el Regne Unit. Per fer l'anàlisi, introdueixo comerç internacional en un model de creixement neoclàssicc amb dos sectors, agricultura i no-agricultura. Una característica clau del model és la baixa elasticitat-ingrés del bé agrícola.

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[cat] El comerç internacional en béns agrícoles té el potencial d'accelerar la transformació estructural dels països amb baixa productivitat agrícola perquè els dóna la possiblitat d'importar aliments. L'objectiu d'aquest article és estudiar l'importància del comerç internacional en aquest context a través dels exemples de Corea del Sud i el Regne Unit. Per fer l'anàlisi, introdueixo comerç internacional en un model de creixement neoclàssicc amb dos sectors, agricultura i no-agricultura. Una característica clau del model és la baixa elasticitat-ingrés del bé agrícola.

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A new troglobitic species, Nesticus baeticus sp. n. (♂♀), inhabiting the karst landscapes of the high part of the Cazorla, Segura and Las Villas Natural Park (NE Jaén, Spain) where it has been found in 8 caves is diagnosed and described, its distribution and habitat are also analyzed.The new species belongs to the Iberian species group that includes Nesticus luquei, Nesticus lusitanicus and Nesticus murgis. Evolutionary relationships of the Iberian Nesticus species are discussed on the basis of morphological and molecular data (cox1 and rrnL). Arachnida, Araneae, taxonomy, description, new species, caves, Iberian Peninsula, Mediterranean basin