988 resultados para Exploitation


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Hancornia speciosa Gomes is a fruit tree native from Brazil that belongs to Apocinaceae family, and is popularly known as Mangabeira. Its fruits are widely consumed raw or processed as fruit jam, juices and ice creams, which have made it a target of intense exploitation. The extractive activities and intense human activity on the environment of natural occurrence of H. speciosa has caused genetic erosion in the species and little is known about the ecology or genetic structure of natural populations. The objective of this research was the evaluation of the genetic diversity and genetic structure of H. speciosa var. speciosa. The genetic variability was assessed using 11 allozyme loci with a sample of 164 individuals distributed in six natural populations located in the States of Pernambuco and Alagoas, Northeastern Brazil. The results showed a high level of genetic diversity within the species (e= 0.36) seeing that the most of the genetic variability of H. speciosa var. speciosa is within its natural populations with low difference among populations ( or = 0.081). The inbreeding values within ( = -0.555) and among populations ( =-0.428) were low showing lacking of endogamy and a surplus of heterozygotes. The estimated gene flow ( m ) was high, ranging from 2.20 to 13.18, indicating to be enough to prevent the effects of genetic drift and genetic differentiation among populations. The multivariate analyses indicated that there is a relationship between genetic and geographical distances, which was confirmed by a spatial pattern analysis using Mantel test (r = 0.3598; p = 0.0920) with 1000 random permutations. The high genetic diversity index in these populations indicates potential for in situ genetic conservation.

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Many species are able to learn to associate behaviours with rewards as this gives fitness advantages in changing environments. Social interactions between population members may, however, require more cognitive abilities than simple trial-and-error learning, in particular the capacity to make accurate hypotheses about the material payoff consequences of alternative action combinations. It is unclear in this context whether natural selection necessarily favours individuals to use information about payoffs associated with nontried actions (hypothetical payoffs), as opposed to simple reinforcement of realized payoff. Here, we develop an evolutionary model in which individuals are genetically determined to use either trial-and-error learning or learning based on hypothetical reinforcements, and ask what is the evolutionarily stable learning rule under pairwise symmetric two-action stochastic repeated games played over the individual's lifetime. We analyse through stochastic approximation theory and simulations the learning dynamics on the behavioural timescale, and derive conditions where trial-and-error learning outcompetes hypothetical reinforcement learning on the evolutionary timescale. This occurs in particular under repeated cooperative interactions with the same partner. By contrast, we find that hypothetical reinforcement learners tend to be favoured under random interactions, but stable polymorphisms can also obtain where trial-and-error learners are maintained at a low frequency. We conclude that specific game structures can select for trial-and-error learning even in the absence of costs of cognition, which illustrates that cost-free increased cognition can be counterselected under social interactions.

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Twenty Audouin´s gulls, Larus audouinii, breeding in the Ebro Delta (NW Mediterranean) were radio-tracked in 1998 to study their foraging behaviour and activity patterns. Some detrimental effects of tagging on the breeding success of the birds were detected, especially when both members of the pair were tagged. The results were actually constrained by the low number of locations due to natural breeding failure and failure in tag emission, as well as the adverse effect of tagging. However, through a combination of aircraft surveys at sea and a fixed station for automatic tracking of the presence of the birds at the colony, novel individual-based information of home ranges and activity patterns was obtained. Trawler fishing activity seemed to influence both the foraging range and habitat use: while trawlers operated, gulls overlapped their fishing grounds with vessels, probably to scavenge on discards. Very few locations were obtained during a trawling moratorium period, although they were all recorded in coastal bays and terrestrial habitats. During the trawling activity period, gulls ranged over a minimum convex polygon area of 2900 km2. Gulls were tracked up to 40 km from the colony, but some individuals were observed beyond 150 km while still breeding. Arrivals and departures from the colony were in accordance with the trawling timetable. However, most birds also showed some nocturnal foraging activity, probably linked to active fishing of clupeoids (following diel migrations) or to the exploitation of purse-seine fishing activity. Foraging trips lasted on average 15 hours: males performed significantly shorter trips than females, which spent more time outside the colony. The proportion of nocturnal time involved in the foraging trips was the same for males and females, but whilst all males initiated their trips both during the day and at night, some females only initiated their trips during the day. Hatching success was found to be related to foraging effort by males. Gulls spent on average ca. 38% of their time budget outside the nesting territory, representing the time devoted mainly to flying, foraging and other activities.

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From the early 17th century to the 1970s southern right whales, Eubalaena australis, were subject to intense exploitation along the Atlantic coast of South America. Catches along this coast recorded by whalers originally formed a continuum from Brazil to Tierra del Fuego. Nevertheless, the recovery of the population has apparently occurred fragmentarily, and with two main areas of concentration, one off southern Brazil (Santa Catarina) and another off central Argentina (Peninsula Valdés). This pattern suggests some level of heterogeneity amongst the population, which is apparently contradicted by records that traced individuals moving throughout the whole geographical extension covered by the species in the Southwest Atlantic. To test the hypothesis of the potential occurrence of discrete subpopulations exploiting specific habitats, we investigated N, C and O isotopic values in 125 bone samples obtained from whaling factories operating in the early 1970s in southern Brazil (n = 72) and from contemporary and more recent strandings occurring in central Argentina (n = 53). Results indicated significant differences between the two sampling areas, being δ13C and δ18O values significantly higher in samples from southern Brazil than in those from central Argentina. This variation was consistent with isotopic baselines from the two areas, indicating the occurrence of some level of structure in the Southwest Atlantic right whale population and equally that whales more likely feed in areas commonly thought to exclusively serve as nursing grounds. Results aim at reconsidering of the units currently used in the management of the southern right whale in the Southwest Atlantic Ocean. In the context of the current die-off affecting the species in Peninsula Valdés, these results also highlight the necessity to better understand movements of individuals and precisely identify their feeding areas.

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Ants are among the most problematic invasive species. They displace numerous native species, alter ecosystem processes, and can have negative impacts on agriculture and human health. In part, their success might stem from a departure from the discovery-dominance trade-off that can promote co-existence in native ant communities, that is, invasive ants are thought to be at the same time behaviorally dominant and faster discoverers of resources, compared to native species. However, it has not yet been tested whether similar asymmetries in behavioral dominance, exploration, and recruitment abilities also exist among invasive species. Here, we establish a dominance hierarchy among four of the most problematic invasive ants (Linepithema humile, Lasius neglectus, Wasmannia auropunctata, Pheidole megacephala) that may be able to arrive and establish in the same areas in the future. To assess behavioral dominance, we used confrontation experiments, testing the aggressiveness in individual and group interactions between all species pairs. In addition, to compare discovery efficiency, we tested the species' capacity to locate a food resource in a maze, and the capacity to recruit nestmates to exploit a food resource. The four species differed greatly in their capacity to discover resources and to recruit nestmates and to dominate the other species. Our results are consistent with a discovery-dominance trade-off. The species that showed the highest level of interspecific aggressiveness and dominance during dyadic interactions.

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Työn tavoitteena oli kehittää alihankintaosia valmistavalle kevytmetallivalimolle Balanced Scorecard - malliin pohjautuva suorituskyvyn mittausjärjestelmä. Mittariston tarkoituksena on kasvattaa yritysjohdon tietämystä yrityksen eri toimintojen suorituskyvystä ja tarjota informaatiota päätöksenteon tueksi. Tarve suorituskyvyn mittaamiselle on syntynyt yrityksen kasvaessa ja asiakaspohjan laajentuessa. Työn alussa tutkittiin kirjallisuutta liittyen suorituskyvyn mittaamiseen. Tämän jälkeen tutkittiin strategiatyötä Balanced Scorecard – projektin yhteydessä ja itse Balanced Scorecard – projektiin liittyviä kysymyksiä. Teoriatiedon pohjalta muodostettiin kohdeyrityksen Balanced Scorecard. Ensin täsmennettiin yrityksen visiota ja strategiaa hyvän mittariston luomiseksi. Mittarit valittiin pohjautuen kriittisiin menestystekijöihin ja ne sijoitettiin näkökulmiin, jotka ovat sisäisten prosessien näkökulma, asiakasnäkökulma, talousnäkökulma sekä kasvun ja kehityksen näkökulma. Sisäisten prosessien näkökulmaan sijoitettiin tuotekohtaisia, osastokohtaisia ja toimittajakohtaisia mittareita. Mittaristo ei suinkaan ole projektin päätyttyä valmis vaan sitä tulee kehittää jatkuvasti. Mittariston käyttöönotto avaa mahdollisuuksia niin toiminnanohjausjärjestelmän paremmalle hyödyntämiselle kuin tavoitehinnoittelun käyttöönotolle. Myös asiakaskannattavuuslaskennan käyttöönottoa tulevaisuudessa kannattaa harkita.

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Tämän diplomityön tavoitteena on kuvata Teknologian kehittämiskeskuksen (Tekes) teknologiaohjelmien päätöksentekoa sekä kehittää teknologiaohjelman päätöksentekoa tukevia tiedon esittämistapoja eli projektisalkkunäkymiä. Työssä käytettiin laadullista tutkimusotetta. Työn toteuttamisessa noudatettiin osallistuvan havainnoinnin toiminta-tutkimuksen periaatteita. Siinä tutkija itse osallistuu havaitun tutkimusongelman ratkaisuun yhdessä tutkimuskohteensa kanssa. Tämän työn empiirinen aineisto kerättiin vuoden 2002 ja 2003 aikana toteutetun teknologiaohjelman ohjaustyökalun pilotointiprojektin yhteydessä. Pilotointiprojektin aikana tehdyt havainnot ja kehittämistyön kuvaus ja tulokset on koottu työn empiriassa esiteltyihin analyyseihin, johtopäätöksiin sekä jatkotoimenpide-ehdotuksiin. Työn tutkimustuloksina voidaan esittää, että teknologiaohjelman päätöksenteko perustuu ohjelman nykytilaan, tulevaisuuteen, projektien hyödyntämispotentiaaliin, haastavuuteen sekä verkottumiseen liittyvien tietojen tarkasteluun. Päätöksenteko jakaantuu ohjelmaorganisaation edustajien johtoryhmän, ohjelmapäällikön ja teknologia-asiantuntijan kesken. Heillä on päätöksentekoon, kommentointiin, esittelyyn sekä tiedoksisaantiin liittyviä rooleja. Nykyisin teknologiaohjelmien päätöksentekokäytännöt vaihtelevat ohjelmittain hyvinkin paljon. Päätöksentekoon kaivataan systematiikkaa sekä objektiivisuutta. Pilotointiprojektissa saatujen kokemusten perusteella visualisoidut projektisalkkunäkymät antavat teknologiaohjelmien päätöksenteolle kaivattua tukea. Salkkunäkymien avulla voidaan tarkastella ohjelman nykytilaa, tulevaisuutta, verkottumista, riskejä sekä tuotto-odotuksia. Salkkunäkymien tuottamisen helpottamiseksi tulisi edelleen kehittää projektikohtaisen tiedon keräämistapoja sekä projektisalkun hallinta-prosesseja.

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What does it feel like to own, to control, and to be inside a body? The multidimensional nature of this experience together with the continuous presence of one's biological body, render both theoretical and experimental approaches problematic. Nevertheless, exploitation of immersive virtual reality has allowed a reframing of this question to whether it is possible to experience the same sensations towards a virtual body inside an immersive virtual environment as toward the biological body, and if so, to what extent. The current paper addresses these issues by referring to the Sense of Embodiment (SoE). Due to the conceptual confusion around this sense, we provide a working definition which states that SoE consists of three subcomponents: the sense of self-location, the sense of agency, and the sense of body ownership. Under this proposed structure, measures and experimental manipulations reported in the literature are reviewed and related challenges are outlined. Finally, future experimental studies are proposed to overcome those challenges, toward deepening the concept of SoE and enhancing it in virtual applications.

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Tutkielman tavoitteena on toimintolaskentajärjestelmän kehittäminen osaksi case-yrityksen johdon informaatiojärjestelmää. Tutkielman empiirisessä osassa selvitetään haastattelujen ja osallistuvan havainnoinnin avulla toimintolaskennan asema ja nykytila sekä sille asetettavat tavoitteet. Tutkimusmetodologia on konstruktiivinen ja metodi case-tutkimus. Case-yrityksessä käytettiin toimintolaskentaa yrityksen kehittämisprojektissa vuonna 1997. Sen hyväksikäyttö on muuten ollut vähäistä. Yrityksen omistussuhteissa tapahtuneet muutokset, siitä johtuva resurssipula sekä taulukkolaskennalla toteutetun laskentamallin kankeus ovat olleet siihen osittain syynä. Toimintolaskenta rinnakkaisena laskentajärjestelmänä on jäänyt toissijaiseksi. Yrityksen johtoryhmän jäsenet odottavat toimintolaskentajärjestelmältä tällä hetkellä ensisijaisesti tuotekoodi- ja asiakaskannattavuuksien selvittämistä. Yksinkertaistamalla mallia ja helpottamalla päivittämistä saadaan tuotekoodien kustannukset ja kannattavuudet nopeammin. Yhdistämällä ne muista tietojärjestelmistä saataviin tietoihin pystytään tarvittaessa laskemaan asiakaskannattavuudet. Johtoryhmä saa näin tarvitsemansa kannattavuustiedon tuotteista ja asiakkaista päätöstensä tueksi.

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This paper focuses that geological resources is an essential need in the development of the society and specially of the developing countries. Taking into account the processes and environmental problems related to mining exploitation, these activities should be performed in a environment concordance. For these reason al1 the available environmental techniques and tools for a responsible exploitation of resources should be used.

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The exploitation of real option analysis and real options reasoning to the value of research and development programs was studied in the context of two companies listed and operating in Finland. The companies saw real option analysis as a complex tool to be used to value research and development programs. Materials which were analyzed by qualitative methods were collected using inquiries and interviews. Real options reasoning observed to be more feasible to analyze research and development programs lasting for a couple of years than real option analysis. Where an uncertain investment environment prevailed real options reasoning offer a strategic tool to the company and enable uniform evaluation of research and development programs. Real options reasoning offer a possibility to the companies to systematize and rationalize the management and valuation of technology options.

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Depuis vingt ans, la communauté internationale promeut le développement de contrats d'accès aux ressources génétiques afin d'assurer une exploitation durable et équitable de la biodiversité. On constate cependant que les impacts de telles politiques sont limités, en termes de conservation de la nature comme de justice environnementale ou de retombées financières pour les populations locales. Leur influence sur les agendas et les positionnements des gouvernements des pays émergents et de certains scientifiques est en revanche manifeste. Une grande partie de ces derniers a en effet été convertie aux instruments économiques de mise en valeur de la biodiversité : filières de produits naturels, projets d'écotourisme, paiements pour services environnementaux... Les formes de savoirs et de pouvoirs construits sur la biodiversité et les services écosystémiques témoignent de ce ralliement. Le pari de cet ouvrage est ainsi d'analyser le « pouvoir de la biodiversité » en termes d'économie politique, à partir de l'examen des régimes de propriété industrielle sur le vivant dans trois pays émergents - le Vietnam, le Brésil et le Mexique - et d'études de cas sur la mobilisation des savoirs de communautés autochtones et locales dans ces pays. Les notions de biodiversité et de services écosystémiques et leur diffusion ne seraient-elles pas avant tout les marqueurs d'une néolibéralisation des politiques de conservation de la nature ?

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In this paper we present ClInt (Clinical Interview), a bilingual Spanish-Catalan spoken corpus that contains 15 hours of clinical interviews. It consists of audio files aligned with multiple-level transcriptions comprising orthographic, phonetic and morphological information, as well as linguistic and extralinguistic encoding. This is a previously non-existent resource for these languages and it offers a wide-ranging exploitation potential in a broad variety of disciplines such as Linguistics, Natural Language Processing and related fields.

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L'investigateur forensique est confronté à une vaste typologie de traces qui comprend notamment les plumes d'oiseaux. La présente contribution a pour but de fournir les éléments nécessaires pour mieux discerner le potentiel informatif de ces dernières et donner un aperçu global des différents examens pouvant être réalisés sur les plumes dans un contexte forensique. Il s'agit également de mettre en évidence les avantages et les limitations de chaque méthode ainsi que leur capacité de discrimination. Cet article présente finalement plusieurs exemples d'affaires dans lesquelles un examen de plumes a contribué de manière non négligeable à l'enquête et propose des pistes de réflexion sur le traitement et l'exploitation de ce type particulier de traces dans le futur.

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Des programmes de recherche pluridisciplinaires sur l’occupation du sol et le pastoralisme de la Préhistoire au Moyen Âge dans le sud du massif alpin sont menés, depuis 1998, sur les massifs du Haut Champsaur, de Freissinières et de l’Argentièrois (Hautes-Alpes). Des dix phases d’occupation et d'activité agropastorale mises en évidence (prospections pédestres et fouilles), entre 1600 et 2700 m d’altitude, trois se distinguent: la fin du Néolithique, l’âge du Bronze et la période médiévale. Au travers des premières données archéologiques et environnementales, cet article présente, depuis le milieu du IIIe millénaire au début du Ier millénaire, les grandes caractéristiques de l’occupation du sol mais aussi l’originalité et l’importance de l’activité humaine dans cette zone alpine. La fin du Néolithique et l’âge du Bronze correspondent à une multiplication des gisements archéologiques marquant de façon évidente une rupture dans la gestion de l'espace montagnard. Les paysages sont largement façonnés par les activités humaines et l’entretien des terres cultivées, des prairies et des alpages, paraît continu. À la lumière des données de terrain, l’une des évolutions qui apparaît sur les sites d’altitude durant cette période concerne l’apparition de structures pastorales bâties entre 2 067 et 2 303 m d’altitude (datation 14C).