954 resultados para Net N mineralization


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The objective of this work was to evaluate the alterations in carbon and nitrogen mineralization due to different soil tillage systems and groundcover species for intercropped orange trees. The experiment was established in an Ultisol soil (Typic Paleudults) originated from Caiuá sandstone in northwestern of the state of Paraná, Brazil, in an area previously cultivated with pasture (Brachiaria humidicola). Two soil tillage systems were evaluated: conventional tillage (CT) in the entire area and strip tillage (ST) with a 2-m width, each with different groundcover vegetation management systems. The citrus cultivar utilized was the 'Pera' orange (Citrus sinensis) grafted onto a 'Rangpur' lime rootstock. The soil samples were collected at a 0-15-cm depth after five years of experiment development. Samples were collected from under the tree canopy and from the inter-row space after the following treatments: (1) CT and annual cover crop with the leguminous Calopogonium mucunoides; (2) CT and perennial cover crop with the leguminous peanut Arachis pintoi; (3) CT and evergreen cover crop with Bahiagrass Paspalum notatum; (4) CT and cover crop with spontaneous B. humidicola grass vegetation; and (5) ST and maintenance of the remaining grass (pasture) of B. humidicola. The soil tillage systems and different groundcover vegetation influenced the C and N mineralization, both under the tree canopy and in the inter-row space. The cultivation of B. humidicola under strip tillage provided higher potential mineralization than the other treatments in the inter-row space. Strip tillage increased the C and N mineralization compared to conventional tillage. The grass cultivation increased the C and N mineralization when compared to the others treatments cultivated in the inter-row space.

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The Cerro Quema district, located on the Azuero Peninsula, Panama, is part of a large regional hydrothermal system controlled by regional faults striking broadly E-W, developed within the Río Quema Formation. This formation is composed of volcanic, sedimentary and volcano-sedimentary rocks indicating a submarine depositional environment, corresponding to the fore-arc basin of a Cretaceous-Paleogene volcanic arc. The structures observed in the area and their tectono-stratigraphic relationship with the surrounding formations suggest a compressive and/or transpressive tectonic regime, at least during Late Cretaceous-Oligocene times. The igneous rocks of the Río Quema Formation plot within the calc-alkaline field with trace and rare earth element (REE) patterns of volcanic arc affinity. This volcanic arc developed on the Caribbean large igneous province during subduction of the Farallon Plate. Mineralization consists of disseminations of pyrite and enargite as well as a stockwork of pyrite and barite with minor sphalerite, galena and chalcopyrite, hosted by a subaqueous dacitic lava dome of the Río Quema Formation. Gold is present as submicroscopic grains and associated with pyrite as invisible gold. A hydrothermal alteration pattern with a core of advanced argillic alteration (vuggy silica with alunite, dickite, pyrite and enargite) and an outer zone of argillic alteration (kaolinite, smectite and illite) has been observed. Supergene oxidation overprinted the hydrothermal alteration resulting in a thick cap of residual silica and iron oxides. The ore minerals, the alteration pattern and the tectono-volcanic environment of Cerro Quema are consistent with a high sulfidation epithermal system developed in the Azuero peninsula during pre-Oligocene times.

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In the last decade, an important debate has arisen about the characteristics of today"s students due to their intensive experience as users of ICT. The main belief is that frequent use of technologies in everyday life implies that competent users are able to transfer their digital skills to learning activities. However, empirical studies developed in different countries reveal similar results suggesting that the"digital native" label does not provide evidence of a better use of technology to support learning. The debate has to go beyond the characteristics of the new generation and focus on the implications of being a learner in a digitalised world. This paper is based on the hypothesis that the use of technology to support learning is not related to whether a student belongs to the Net Generation, but that it is mainly influenced by the teaching model. The study compares behaviour and preferences towards ICT use in two groups of university students: face-to-face students and online students. A questionnaire was applied to a sample of students from five universities with different characteristics (one offers online education and four offer face-to-face education with LMS teaching support). Findings suggest that although access to and use of ICT is widespread, the influence of teaching methodology is very decisive. For academic purposes, students seem to respond to the requirements of their courses, programmes, and universities. There is a clear relationship between students" perception of usefulness regarding certain ICT resources and their teachers" suggested uses of technologies. The most highly rated technologies correspond with those proposed by teachers. The study shows that the educational model (face-to-face or online) has a stronger influence on students" perception of usefulness regarding ICT support for learning than the fact of being a digital native.

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WDM (Wavelength-Division Multiplexing) optiset verkot on tällä hetkellä suosituin tapa isojen määrän tietojen siirtämiseen. Jokaiselle liittymälle määrätään reitin ja aallonpituus joka linkin varten. Tarvittavan reitin ja aallon pituuden löytäminen kutsutaan RWA-ongelmaksi. Tämän työn kuvaa mahdollisia kustannuksen mallein ratkaisuja RWA-ongelmaan. Olemassa on paljon erilaisia optimoinnin tavoitteita. Edellä mainittuja kustannuksen malleja perustuu näillä tavoitteilla. Kustannuksen malleja antavat tehokkaita ratkaisuja ja algoritmeja. The multicommodity malli on käsitelty tässä työssä perusteena RV/A-kustannuksen mallille. Myöskin OB käsitelty heuristisia menetelmiä RWA-ongelman ratkaisuun. Työn loppuosassa käsitellään toteutuksia muutamalle mallille ja erilaisia mahdollisuuksia kustannuksen mallein parantamiseen.

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Tutkielman tavoitteena on selvittää kuinka suunnitella ja hallita tehokasta verkkoviestintää, joka vastaa kohdeyleisön ja palvelun ylläpitäjien kasvaviin vaatimuksiin. Tutkielma on normatiivinen tapaustutkimus, jonka tuloksena syntyy konstruktiivinen askelmalli kokonaisvaltaisen verkkoviestintäprojektin toteuttamiseen. Tutkimus esittää myös teoreettisesti merkittävän näkökulman verkkopalvelujen sisällön hallintaongelmien ratkaisemiseen. Tosielämän verkkoviestintäprojektin toteutusta seurataan TietoEnator Forestissa, jossa tutkielman kirjoittaja työskentelee. Tutkimusmateriaalina käytetään 11 TietoEnator Forestissa toteutettua haastattelua, TietoEnator konsernin dokumentaatiota ja osallistuvaa havainnointia. Haastattelulomake sisältää 13 avointa kysymystä, jotka käsittelevät verkkoviestintästrategian perusasioita. Tunnistetut verkkoviestinnän avainmenestystekijät ovat vahva sisäinen sitoutuminen hajautettuihin ylläpitorooleihin ja perinpohjainen asiakastarpeiden tunnistaminen. Teknisesti on tärkeää, että eritason verkkoympäristöt, Internet, Intranet ja Extranet, hallitaan samoilla sisällönhallinta työkaluilla. Näin pystytään rationalisoimaan ylläpitotoiminnot.

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L’objectiu d’aquest treball ha estat l’anàlisi dels dos nous documents comptables, l’Estat de Canvis en el Patrimoni Net – ECPN – i l’Estat de Fluxos d’Efectiu – EFE‐, introduïts amb la reforma comptable de 2007 [Reial Decret 1514/2007 de 16 de novembre i Reial Decret 1515/2007 per a petites i mitjanes empreses]. Aquest anàlisis s’ha portat a terme amb la finalitat d’analitzar com ha millorat i augmentat la informació per la presa de millors decisions tant per les empreses com per analistes externs. El treball consta de dues parts, la primera part està formada per un anàlisis teòric d’aquests dos documents. La segona part està formada per un anàlisis pràctic de les empreses del sector de Materials Bàsics, Indústria i Construcció de la Borsa de Madrid. D’aquestes empreses s’ha realitzat un anàlisis convencional i l’ anàlisis dels corresponents ECPN i EFE de cadascuna de les empreses, amb l’objectiu de comprovar la millora de la informació.

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Dopamine release in the prefrontal cortex plays a critical role in cognitive function such as working memory, attention and planning. Dopamine exerts complex modulation on excitability of pyramidal neurons and interneurons, and regulates excitatory and inhibitory synaptic transmission. Because of the complexity of this modulation, it is difficult to fully comprehend the effect of dopamine on neuronal network activity. In this study, we investigated the effect of dopamine on local high-frequency oscillatory neuronal activity (in β band) in slices of the mouse anterior cingulate cortex (ACC). We found that dopamine enhanced the power of these oscillations induced by kainate and carbachol, but did not affect their peak frequency. Activation of D2R and in a lesser degree D1R increased the oscillation power, while activation of D4R had no effect. These high-frequency oscillations in the ACC relied on both phasic inhibitory and excitatory transmission and functional gap junctions. Thus, dopamine released in the ACC promotes high-frequency synchronized local cortical activity which is known to favor information transfer, fast selection and binding of distributed neuronal responses. Finally, the power of these oscillations was significantly enhanced after degradation of the perineuronal nets (PNNs) enwrapping most parvalbumin interneurons. This study provides new insights for a better understanding of the abnormal prefrontal gamma activity in schizophrenia (SZ) patients who display prefrontal anomalies of both the dopaminergic system and the PNNs.

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Network neutrality is a growing policy controversy. Traffic management techniques affect not only high-speed, high-money content, but by extension all other content too. Internet regulators and users may tolerate much more discrimination in the interests of innovation. For instance, in the absence of regulatory oversight, ISPs could use Deep Packet Inspection (DPI) to block some content altogether, if they decide it is not to the benefit of ISPs, copyright holders, parents or the government. ISP blocking is currently widespread in controlling spam email, and in some countries in blocking sexually graphic illegal images. In 1999 this led to scrutiny of foreclosure of Instant Messaging and video and cable-telephony horizontal merger. Fourteen years later, there were in 2013 net neutrality laws implemented in Slovenia, the Netherlands, Chile and Finland, regulation in the United States and Canada , co-regulation in Norway, and self-regulation in Japan, the United Kingdom and many other European countries . Both Germany and France in mid-2013 debated new net neutrality legislation, and the European Commission announced on 11 September 2013 that it would aim to introduce legislation in early 2014. This paper analyses these legal developments, and in particular the difficulty in assessing reasonable traffic management and ‘specialized’ (i.e. unregulated) faster services in both EU and US law. It also assesses net neutrality law against the international legal norms for user privacy and freedom of expression

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This article explores whether use of the Internetchanges the role that political motivation hastraditionally played in classic explanations ofparticipation. We ask if, by reducing so dramatically the costs of political participation,the Internet causes interest in politics to loseimportance as a causal factor of participation.We examine this issue analysing a representativesurvey of the Spanish population which deals withpolitical participation and Internet use. Theresults show that use of Internet has a directeffect on participation independently of motivation, and that, in order to participate online, skilled Internet users do not need to be motivated or interested in politics.

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En este TFM se detallan las mejoras realizadas a la aplicación eXeLearning.net, así como otras aportaciones a la comunidad realizadas durante el proyecto de fin de máster de Software libre. eXeLearning.net es una aplicación de software libre para la creación de materiales educativos digitales, desarrollada en Python, con una interfaz web (HTML + JavaScript). En este proyecto se desarrollaron entre otras cosas: un repositorio de estilos en la web oficial de la aplicación, disponibles para su descarga desde la aplicación de escritorio, la creación y mantenimiento de un repositorio en Launchpad y una funcionalidad para publicar los contenidos creados con eXeLearning.net directamente en Google Drive.

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El portal web FastJob tiene como objetivo principal la gestión de ofertas de trabajo tanto a nivel de empresa como de la persona que busca un nuevo empleo. Este proyecto también recogerá la funcionalidad necesaria para el mantenimiento de los usuarios y las ofertas de trabajo, facilitando así el cumplimiento del objetivo principal.

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L'empresa d'obres i reformes Ortbot SL ha sol·licitat una aplicació via web per poder portar el control de la gestió de la seva empresa. Aquesta aplicació ha d'ésser fàcil d'utilitzar, ha de tenir un disseny atractiu i que compleixi els requisits bàsics per al bon funcionament de l'empresa, així com poder cobrir les seves noves necessitats.