Canada, a child's play

Science4you, a Portuguese developer, producer and seller of scientific and educational toys, leveraged the worldwide growth of this category to successfully expand its operations abroad. Following a recent entry into the United States market, the purpose of this report is to help the company define the next step in its international expansion. A customized scoring model, based on a set of relevant macro and micro-criteria was developed for Anglo-Saxon and Asian countries, yielding Canada as the market with the highest potential. The recommended entry mode is direct exporting via an independent distributor, being complemented with a financial and risk analysis.

Plan to bear fruit

Frutaformas is a Portuguese micro-enterprise, specialized in the production of premium dehydrated-fruit, an emerging snack category fostered by the increasing trend for healthier alimentary habits in developed countries. The relatively small size of the domestic market and the growing competition led Frutaformas to consider Europe as an attractive for export market. A scoring model based on a set of macro and micro-level criteria suggested the United Kingdom as the preferential target country at this stage. Recommendations on the entry mode and the associated risks were elaborated taking into account the country and industry analysis as well as Frutaformas’ unique organizational platform.

A network approach to brain aging through multimodal neuroimaging

Tese de Doutoramento em Ciências da Saúde.

L'autonomie obligatoire : analyse sociologique des dispositifs scolaires de l'autonomie

La thèse traite des injonctions à l'autonomie dans le champ scolaire et des pratiques destinées à favoriser son développement chez les élèves. Elle se base sur une enquête ethnographique réalisée dans une école primaire genevoise, réunissant des observations menées durant deux ans et demi dans des classes allant de la 2° enfantine à la 3e primaire (2P-5P, selon HARMOS) et des entretiens d'enseignants, complétée par des observations dans les familles et des entretiens d'enfants et de leurs parents. Elle met en évidence le paradoxe auquel sont quotidiennement confrontés les enseignants qui doivent amener les élèves à découvrir et s'approprier les savoirs et les règles scolaires de manière autonome, tout en encadrant leurs pratiques afin que ceux-ci se conforment aux attentes de l'institution scolaire. La notion de dispositif, en tant qu'échelle intermédiaire d'analyse (Bonnéry, 2009), rend possible l'articulation des niveaux macro- et micro-sociologique dans l'analyse des pratiques. L'analyse des dispositifs scolaires de l'autonomie considère la traduction de la norme d'autonomie et des injonctions institutionnelles dans les pratiques individuelles. L'autonomie est ici définie comme un principe de socialisation, sur le mode de l'engagement : les dispositifs scolaires de l'autonomie visent à amener les élèves à choisir, vouloir, aimer ce que l'institution scolaire leur demande. Cette analyse permet de dégager plusieurs types de dispositifs et surtout de mettre en lumière leurs contradictions internes lorsque ne sont pas perçues ou partagées par les acteurs les attentes implicites ou explicites contenues dans les dispositifs. L'analyse des dispositifs porte également, dans une perspective plus interactionniste, sur les stratégies individuelles de gestion des contradictions et la retraduction des normes par les acteurs. Les dispositifs sont alors examinés sous l'angle des processus d'étiquetage réalisé par les enseignants et des formes de déviances qu'ils font apparaître chez les élèves et les parents. - The thesis deals with injunctions to autonomy in the field of education and practices used to facilitate its development in students. It is based on an ethnographic survey in Geneva elementary school, bringing together observations made during two and a half years in classes ranging from 2P to 5P (according HARMOS), interviews with teachers, observations in families and interviews with children and their parents. It highlights the paradox that teachers are daily confronted to, as they should encourage students to discover and acquire the knowledge and school rules independently, while framing their practices so that they conform to the expectations of the educational institution. The concept of dispositif as an intermediary level of analysis (Bonnéry, 2009) makes possible the articulation of the macro- and micro-sociological analysis in practices. The analysis of pedagogic dispositives considers the translation of the norm of autonomy and institutional injunctions in individual practices. In this perspective, autonomy is defined as principle of socialization, on the mode of engagement : pedagogic autonomy dispositives designed to encourage students to choose, want, love what institution demands. This analysis identifies several types of dispositives and highlights their internal contradictions when actors do not share expectations. In a more interactionnist perspective, the analysis also includes individual strategies to deal with contradictions and the retranslation of norms by actors. The dispositives are then examined in term of the labelling process conducted by teachers and forms of deviance among students and parents.

Impacts of land leveling on lowland soil physical properties

The practice of land leveling alters the soil surface to create a uniform slope to improve land conditions for the application of all agricultural practices. The aims of this study were to evaluate the impacts of land leveling through the magnitudes, variances and spatial distributions of selected soil physical properties of a lowland area in the State of Rio Grande do Sul, Brazil; the relationships between the magnitude of cuts and/or fills and soil physical properties after the leveling process; and evaluation of the effect of leveling on the spatial distribution of the top of the B horizon in relation to the soil surface. In the 0-0.20 m layer, a 100-point geo-referenced grid covering two taxonomic soil classes was used in assessment of the following soil properties: soil particle density (Pd) and bulk density (Bd); total porosity (Tp), macroporosity (Macro) and microporosity (Micro); available water capacity (AWC); sand, silt, clay, and dispersed clay in water (Disp clay) contents; electrical conductivity (EC); and weighted average diameter of aggregates (WAD). Soil depth to the top of the B horizon was also measured before leveling. The overall effect of leveling on selected soil physical properties was evaluated by paired "t" tests. The effect on the variability of each property was evaluated through the homogeneity of variance test. The thematic maps constructed by kriging or by the inverse of the square of the distances were visually analyzed to evaluate the effect of leveling on the spatial distribution of the properties and of the top of the B horizon in relation to the soil surface. Linear regression models were fitted with the aim of evaluating the relationship between soil properties and the magnitude of cuts and fills. Leveling altered the mean value of several soil properties and the agronomic effect was negative. The mean values of Bd and Disp clay increased and Tp, Macro and Micro, WAD, AWC and EC decreased. Spatial distributions of all soil physical properties changed as a result of leveling and its effect on all soil physical properties occurred in the whole area and not specifically in the cutting or filling areas. In future designs of leveling, we recommend overlaying a cut/fill map on the map of soil depth to the top of the B horizon in order to minimize areas with shallow surface soil after leveling.

The 2013 Arvid Wretlind lecture: evolving concepts in parenteral nutrition.

Fifty years after the clinical introduction of total parenteral nutrition (TPN) the Arvid Wretlind lecture is an opportunity to critically analyse the evolution and changes that have marked its development and clinical use. The standard crystalline amino acid solutions, while devoid of side effects, remain incomplete regarding their composition (e.g. glutamine). Lipid emulsions have evolved tremendously and are now included in bi- and tri-compartmental feeding bags enabling a true "total" PN provided daily micronutrients are prescribed. The question of exact individual energy, macro- and micro-nutrient requirements is still unsolved. Many complications attributed to TPN are in fact the consequence of under- or over-feeding: the historical hyperalimentation concept is the main cause, along with the use of fixed weight based predictive equations (incorrect in 70% of the critically ill patients). In the late 80's many complications (hyperglycemia, sepsis, fatty liver, exacerbation of inflammation, mortality) were attributed to TPN leading to its near abandon in favour of enteral nutrition (EN). Enteral feeding, although desirable for many reasons, is difficult causing a worldwide recurrence of malnutrition by insufficient feed delivery. TPN indications have evolved towards its use either alone or in combination with EN: several controversial trials published 2011-13 have investigated TPN timing, an issue which is not yet resolved. The initiation time varies according to the country between admission (Australia and Israel), day 4 (Swiss) and day 7 (Belgium, USA). The most important issue may prove to be and individualized and time dependent prescription of feeding route, energy and substrates.

One-step nucleic acid amplification (OSNA): a new road to better staging in colon cancer patients?

Introduction: Approximately one fifth of stage I and II colon cancer patients will suffer from recurrent disease. This is partly due to the presence of small nodal tumour infiltrates, which are undetected by standard histopathology using Haematoxylin & Eosin (H&E) staining on one slice and thus may not receive beneficial adjuvant therapy. A new diagnostic, semi-automatic system, called one-step nucleic acid amplification (OSNA), was recently designed for the detection of cytokeratin 19 (CK19) mRNA as a surrogate for lymph node metastases. The objective of the present investigation was to compare the performance of OSNA with both standard H&E as well as intensive histopathologic analyses in the detection of colon cancer lymph node micro- and macro-metastases.Methods: In this prospective study 313 lymph nodes from 22 consecutive stage I - III colon cancer patients were assessed. Half of each lymph node was analysed initially based on one slice of H&E followed by an intensive histologic work-up (5 levels of H&E and immuno-histochemistry staining for each slice), the other half was analysed using OSNA.Results: All OSNA results were available after less than 40 minutes. Fifty-one lymph nodes were positive and 246 lymph nodes negative with both OSNA and standard H&E. OSNA was more sensitive to detect small nodal tumor infiltrates compared to H&E (11 OSNA pos. /H&E neg.). Compared to intensive histopathologic analyses, OSNA had a sensitivity of 94.5% and a specificity of 97.6% to detect lymph node micro- and macro-metastases with a concordance rate of 97.1%. An upstaging due to OSNA was found in 2/13 (15.3%) initially node negative colon cancer patients.Conclusion: OSNA appears to be a powerful and promising molecular tool for the detection of lymph node macro- and micro-metastases in colon cancer patients. OSNA has a similar performance in the detection of micro- and macro-metastases compared to intensive histopathologic investigations and appears to be superior to standard histology with H&E. Since the use of OSNA allows the analysis of the whole lymph node, the problem of sampling bias and undetected tumor deposits due to uninvestigated material will be overcome in the future and OSNA may thus improve staging in colon cancer patients. It is hoped that this improved staging will lead to better patient selection for adjuvant therapy and consecutively improved local and distant control as well as better overall survival.

Nuevas tecnologías, trabajo y paternidad: Las nuevas formas de flexibilidad laboral y sus efectos sobre la implicación de los hombres en el cuidado de los hijos

Los estudios sobre el uso de las tecnologías de la información y comunicación (TIC) para organizar el trabajo y sobre su incidencia en la conciliación entre vida laboral y familiar arrojan resultados ambiguos o contradictorios. Sin embargo, la aparición y la difusión de TIC inalámbricas están provocando intensos cambios en las prácticassociales, incluidas las relaciones entre vida personal y trabajo. Mediante entrevistas en profundidad, un grupo de padres en situaciones laborales diversas han reflexionado sobre cómo utilizan el potencial de movilidad, conectividad y flexibilidad que les ofrecen las nuevas TIC y sobre cómo modula dicho uso la implicación de los hombres en su rol de padres. En línea con trabajos realizados en otros países, los resultados preliminares sugieren que el papel que se atribuye a las TIC como herramientas para la emancipación del rol de género de los hombres mediante su mayor implicación en el cuidado material y afectivo de los hijos depende muchas veces de factores ajenos al uso de estas tecnologías: motivación personal, actitud y percepción de la pareja respecto a la competencia hombre para ejercer de padre, o macro y micro políticas de conciliación existentes en las organizaciones.

Future trends of Finnish cement based construction

The construction material sector, as a capital intensive industry, is highly vulnerable to rapid fluctuations in the economic cycles. In Finland this was witnessed especially during the late 2000s, as in 2007 and 2008 the demand for several construction materials exceeded their supply and right after this, in 2009 the demand collapsed fast as a result of an international recession. These factors brought about the need to study the future trends of the market place of the commissioning company, Finnsementti Oy. As reliable short term market forecasts for the sector are difficult to compose, the study concentrates primarily in examining and identifying the trends that are likely to affect the Finnish cement industry, and as an extension, the concrete industry in a frame of 10 to 15 years. The study’s scope comprehends also the examination of the domestic construction sector, as it represents the end user industry of both cement and concrete. These motives for the study produce the research problem, which is to conduct a trend analysis for cement based building in the Finnish market area in the 2020s. The theoretical frame for composing a trend analysis in the case of this study is twofold. This is due to the fact that both, the macro and micro environments of the examined industries are studied. The main methods used are the PESTE-model (macro) and Porter’s five forces model (micro). The study applies a qualitative approach and the data is gathered by interviewing a group of experts from the cement, concrete and construction industries. The result of the paper is an overall trend analysis for the Finnish cement based building sector, which is based on ‘sub trend analyses’ concerning four identified sub-sectors of the Finnish construction industry. The results are a combination of findings from these sub-sectors and the analyzed data that deals with the studied sector’s macro and micro environment. The conclusions provide an overall picture of the examined sectors’ potential future as a whole and by defined sub-sectors of the construction industry. The recognition of future trends in different areas of the construction industry can be applied as a means for an industry actor’s decision making and in estimating the types of construction that are likely to grow or decline. Finally, based on the analyzed data and conclusions, the commissioning company is provided with a brief SWOT analysis, that provides additional tools for decision making and planning processes regarding the future.

Liiketoiminnan strateginen suunnittelu: Konesali-liiketoiminta

Tässä diplomityössä selvitettiin tukkuliikkeen liiketoimintamahdollisuuksia konesali-liiketoiminnassa. Päätutkimuskysymys oli: Millainen liiketoimintamalli soveltuu kestävään arvontuotantoon tukkuliikkeelle konesali-liiketoiminnassa? Työn teoriaosassa paneudutaan strategiseen suunnitteluun, liiketoimintamalleihin ja liiketoimintamallien suunnitteluun. Teoriaosan pohjalta johdettiin vaatimukset ja luotiin viitekehys liiketoimintamallien suunnittelulle. Ongelmanratkaisu aloitettiin toimintaympäristön analyysillä, jonka pohjalta tunnistettiin liiketoimintamahdollisuuksia. Kerättyä dataa analysoitiin erilaisilla analysointimenetelmillä liikemahdollisuuksien tunnistamiseksi. Tämän jälkeen tunnistettuja liiketoimintamahdollisuuksia arvioitiin ja kaikkein potentiaalisimmat ideat kehitettiin liiketoimintamalleiksi. Työn varsinaiset tulokset jakautuvat kolmeen osaan: Toimintaympäristön analyysiin, kehitettyihin konsepteihin ja suunnitelmaan konseptien käyttöönotosta. Toimintaympäristön analyysi sisältää makro- ja mikroympäristön analysoinnin, joita voidaan hyödyntää, jos jokin liiketoimintamalleista päätetään ottaa käyttöön. Toimintaympäristön analyysin perusteella voidaan tehdä johtopäätös, etteivät tukkuliikkeen resurssit sovellu perinteiseen konesaliliiketoiminnan arvontuotantoon. Tutkimuksen tärkein tulos on kuitenkin kehitetyt liiketoimintamallit, jotka pystyvät hyödyntämään olemassa olevia resursseja ja silti olemaan kilpailukykyisiä konesali-liiketoiminnassa.

Luottamuksen lähteet. Vertaileva tutkimus yleistynyttä luottamusta synnyttävistä mekanismeista

Tutkimuksen aiheena on yleistynyt luottamus. Väitöskirjassa tutkitaan mistä tuntemattomien kansalaisten toisiinsa kohdistama luottamus kumpuaa ja haetaan vastauksia tähän kysymykseen sekä maakohtaisen että vertailevan tutkimuksen avulla. Tutkimus koostuu yhteenvedon lisäksi viidestä tutkimusartikkelista, joissa luottamuksen syntyä tarkastellaan sekä yksilöiden mikrotason vuorovaikutuksen että maiden välisten eroavaisuuksien näkökulmasta. Yleistyneen luottamuksen synnystä on esitetty useita eri teorioita. Tässä tutkimuksessa tarkastellaan näistä kahta keskeisintä. Osa tutkijoista korostaa kansalaisyhteiskunnan ja ruohonjuuritason verkostojen roolia yleistyneen luottamuksen synnyn taustalla. Tämän hypoteesin mukaan kansalaiset, jotka viettävät aikaansa yhdistyksissä tai muissa sosiaalisissa verkostoissa, oppivat muita helpommin luottamaan paitsi täysin tuntemattomiin ihmisiin myös yhteiskunnallisiin instituutioihin (kansalaisyhteiskuntakeskeinen hypoteesi). Toiset taas painottavat yhteiskunnan julkisten instituutioiden merkitystä. Tämä hypoteesi korostaa instituutioiden reiluutta ja oikeudenmukaisuutta (instituutiokeskeinen hypoteesi). Ihmiset pystyvät luottamaan toisiinsa ja ratkaisemaan kollektiivisia ongelmiaan yhdessä silloin kun esimerkiksi poliittiset ja lainsäädännölliset instituutiot pystyvät luomaan tähän tarvittavan toimintaympäristön. Aineistoina käytetään kansallisia (Hyvinvointi- ja palvelut) sekä kansainvälisiä vertailevia kyselytutkimuksia (European Social Survey ja ISSP). Yksilö- ja makrotason analyyseja yhdistämällä selvitetään yleistynyttä luottamusta selittäviä tekijöitä sekä mekanismeja joiden kautta yleistynyt luottamus muodostuu. Väitöskirjan tulokset tukevat suurimmaksi osaksi instituutiokeskeiseen suuntaukseen sisältyviä hypoteeseja yleistyneen luottamuksen kasautumisesta. Kuitenkin myös esimerkiksi yhdistystoiminnalla havaittiin olevan joitakin yhdistysjäsenien ulkopuolelle ulottuvia myönteisiä vaikutuksia kansalaisten luottamukseen, mikä taas tukee kansalaisyhteiskuntakeskeistä hypoteesia. Tutkimuksen keskeinen tulos on, että kaiken kaikkiaan luottamus näyttäisi kukoistavan maissa, joissa kansalaiset kokevat julkiset instituutiot oikeudenmukaisina sekä reiluina, kansalaisyhteiskunnan roolin luottamuksen synnyttämisessä ollessa tälle alisteinen. Syyksi tähän on oletettu, että näissä maissa (erityisesti pohjoismaiset hyvinvointivaltiot) harjoitettu universaali hyvinvointipolitiikka ja palvelut ovat keskeisiä korkeaa yleistynyttä luottamusta selittäviä tekijöitä. Toisaalta maavertailuissa tätä yhteyttä on selitetty myös sillä, että näissä yhteiskunnassa ei ole paikannettavissa selkeää kulttuurisesti erottuvaa alaluokkaa. Tämän tutkimuksen tulokset tukevat enemmän universaalin hyvinvointivaltion oikeudenmukaisuuteen liittyviä ominaisuuksia alaluokkaistumishypoteesin sijaan. Toisaalta mikrotasolla tarkasteltuna yleistyneen luottamuksen ja hyvinvointipalvelujen välinen yhteys liittyy enemmän palveluiden riittävyyteen kuin niiden universaalisuuden asteeseen. Niin ikään maavertailuissa esimerkiksi verotuksen oikeudenmukaisena kokeminen näyttäisi olevan palvelujen saatavuutta tai niihin liittyviä oikeudenmukaisuuden kokemuksia tärkeämpi seikka yleistyneen luottamuksen kannalta.

Interactions didactiques en classe de français : enseignement/apprentissage de l’accord du verbe en première secondaire

Notre recherche vise à décrire les connaissances grammaticales élaborées par des élèves de première secondaire au cours de l’enseignement/apprentissage de l’accord du verbe. Cette description se fonde sur l’observation des interactions didactiques entre les élèves, et leur enseignant autour de l’objet de savoir « accord du verbe » : elle concerne plus particulièrement l’interaction entre les pôles « élève » et « savoir ». Notre recherche s’inscrit dans le courant de la grammaire pédagogique moderne. La théorie de la transposition didactique de Chevallard (1985/1991) constitue également la pierre angulaire de nos travaux : les concepts de transposition didactique externe (le passage du savoir savant au savoir à enseigner) et interne (le passage du savoir à enseigner au savoir effectivement enseigné) agissent à titre d’analyseurs des interactions didactiques. L’observation, la description et la théorisation des interactions didactiques imposent une démarche écologique pour la collecte des données. Pour notre recherche, les données ont été recueillies grâce à la captation vidéo de séquences didactiques portant sur l’accord du verbe : elles consistent en des interactions verbales entre élèves ou entre les élèves et leur enseignant. L’analyse des données s’est effectuée selon une perspective macro et micro : (1) L’analyse macro indique que les connaissances antérieures des élèves résistent à l’institutionnalisation des savoirs puisque le savoir enseigné n’est pas celui qui est exclusivement mobilisé. Les élèves recourent à un vaste éventail de connaissances de types procédural et déclaratif pour l’identification du verbe et du sujet, dont la réussite n’est par ailleurs pas assurée. De plus, les connaissances qu’ils ont élaborées autour de la règle d’accord et du transfert des traits morphologiques sont également nombreuses et variées et ne les conduisent pas à accorder le verbe avec constance. (2) L’analyse micro suggère que l’élaboration des connaissances relatives à l’accord du verbe dépend de la manière dont les outils de la grammaire (manipulations syntaxiques et phrase de base) sont utilisés par les élèves. Plus précisément, le savoir piétine ou recule lorsque les manipulations syntaxiques ne sont pas appliquées dans la phrase ou qu’elles ne sont pas adaptées dans certains contextes syntaxiques; le savoir fait des bonds en avant dans les classes où les élèves sont en mesure de recourir à la phrase de base pour soutenir leur analyse grammaticale. Les descriptions proposées dans le cadre de notre thèse conduisent à discuter de leurs implications pour la transposition didactique externe et, plus généralement, pour la didactique du français et de la grammaire.

Challenges Faced by Kerala Tourism Industry

Tourism being a smokeless industry is now a multi-billion, multi-sectoral and multi-dimensional activity in the world. Twenty first century tourism has reached up to space when a Russian rocket carried the space vehicle of Dennis Tito, an American businessman and the world’s first space tourist, to the space station. Time is not too far to carry tourists to moon and other planets in specially launched vehicles. Tourism is being considered as an agent of social change bridging gaps among nations, regions and people and helping them to open up. It is a promoter of development-material and spiritual both at macro and micro level. The General Assembly of the United Nations, in designating the year 1967 as ‘International Tourism Year’ recognized the importance of international travel as a means of fostering understanding among people, and giving them a knowledge of the rich heritage of the past civilizations, a better appreciation of the values of different cultures, thus contributing to the strengthening of world peace. It adopted the theme “Tourism-Passport to peace”. Our veteran national leader and the first Prime Minister of India, Jawaharlal Nehru had said” welcome a tourist and send back a friend” which indicates the need for extending friendly hospitality to the in bound tourists. Modern transportation has removed the obstacles of distance enabling people to appreciate each other engage in the exchange of ideas and commerce. Tourism can help overcome real prejudices and foster bonds. Tourism can be a real force of world peace. Considering the vast and varied potential of tourism in the state and its impact on the economic, social and cultural environment of the state, a detailed study is found to be relevant and imperative

Estudio de planeación estratégica : ¿qué pasará con la movilidad para el 2018 en Bogotá, con el surgimiento del sistema de transporte integrado?

En los últimos 15 años se ha discutido sobre las posibles soluciones a las dificultades del sistema integrado de transporte público a las que se enfrenta Bogotá. Restricciones como “Pico y Placa”, el día del “No carro”, sistemas masivos de transporte y la posibilidad de implementar el metro han sido alternativas que no han llegado a su fin de ejecución pero tampoco han logrado formalizarse y aplicarse de tal manera que favorezcan a la movilidad urbana. Nuestro centro de análisis será la movilidad urbana compuesta por diferentes variables que serán estudiadas a nivel macro como la capacidad de la malla vial a nivel de expansión territorial en la ciudad, el parque automotor, el manejo de la administración de la alcaldía en las licitaciones y chatarrización tanto a nivel micro como la cultura de movilidad y la influencia en la calidad de vida por esta tecnificación de transporte. Existen muchos estudios sobre los problemas de movilidad tanto en Latino América como en países Europeos, sin embargo lo que se pretende en este estudio es un planteamiento más general para una concertación de soluciones innovadoras y eficaces en la dirección técnica y política para una realidad territorial y urbana en calidad de servicio.

Optimal management of natural resources. Accounting for heterogeneity

Dynamic optimization methods have become increasingly important over the last years in economics. Within the dynamic optimization techniques employed, optimal control has emerged as the most powerful tool for the theoretical economic analysis. However, there is the need to advance further and take account that many dynamic economic processes are, in addition, dependent on some other parameter different than time. One can think of relaxing the assumption of a representative (homogeneous) agent in macro- and micro-economic applications allowing for heterogeneity among the agents. For instance, the optimal adaptation and diffusion of a new technology over time, may depend on the age of the person that adopted the new technology. Therefore, the economic models must take account of heterogeneity conditions within the dynamic framework. This thesis intends to accomplish two goals. The first goal is to analyze and revise existing environmental policies that focus on defining the optimal management of natural resources over time, by taking account of the heterogeneity of environmental conditions. Thus, the thesis makes a policy orientated contribution in the field of environmental policy by defining the necessary changes to transform an environmental policy based on the assumption of homogeneity into an environmental policy which takes account of heterogeneity. As a result the newly defined environmental policy will be more efficient and likely also politically more acceptable since it is tailored more specifically to the heterogeneous environmental conditions. Additionally to its policy orientated contribution, this thesis aims making a methodological contribution by applying a new optimization technique for solving problems where the control variables depend on two or more arguments --- the so-called two-stage solution approach ---, and by applying a numerical method --- the Escalator Boxcar Train Method --- for solving distributed optimal control problems, i.e., problems where the state variables, in addition to the control variables, depend on two or more arguments. Chapter 2 presents a theoretical framework to determine optimal resource allocation over time for the production of a good by heterogeneous producers, who generate a stock externalit and derives government policies to modify the behavior of competitive producers in order to achieve optimality. Chapter 3 illustrates the method in a more specific context, and integrates the aspects of quality and time, presenting a theoretical model that allows to determine the socially optimal outcome over time and space for the problem of waterlogging in irrigated agricultural production. Chapter 4 of this thesis concentrates on forestry resources and analyses the optimal selective-logging regime of a size-distributed forest.