137,152 research outputs found

    Revalorizando el bosque seco de algarrobo : estudio y an谩lisis de la biodiversidad, distribuci贸n y conservaci贸n de los bosques secos en Lambayeque

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    En nuestro planeta, gran parte del 谩rea continental ha estado cubierta de bosques por millones de a帽os. En el Per煤, tanto la costa, la sierra como la selva poseen grandes bosques, que en conjunto ocupan el 51% del territorio. Los bosques secos son ecosistemas caracter铆sticos de la costa norte peruana, siendo su especie clave el algarrobo (Prosopis pallida), la cual que no solo representa un valor ecol贸gico sino tambi茅n econ贸mico para las comunidades aleda帽as a dichos ecosistemas. Esta investigaci贸n se centra en los bosques de Lambayeque, siendo definidos como representaciones de bosques secos de algarrobo los que se ubican en el Santuario Hist贸rico Bosque de P贸mac, el ACP Chaparr铆 y el ACR Huacrupe La Calera. Actualmente, es evidente que los procesos de deforestaci贸n son las causas m谩s fuertes de la reducci贸n de muchas especies forestales. Esto en conjunto con los bruscos cambios de uso de suelo, los incendios forestales de origen antr贸pico y el cambio clim谩tico vienen afectando a las comunidades humanas y muchas poblaciones de especies animales y vegetales. Una de las especies que se ve amenazada por estos factores es, precisamente, el algarrobo, por lo que su conservaci贸n junto al ecosistema de bosque seco en su plenitud es prioritaria. Por tanto, el objetivo de esta tesis es identificar y plantear qu茅 estrategias son las m谩s adecuadas para conservar y gestionar los bosques secos de manera integrada, de manera que se valoricen los recursos y servicios que ofrecen estos ecosistemas. Se trabaj贸 una metodolog铆a basada en biogeograf铆a de la conservaci贸n, la cual incluy贸 m茅todos de modelamiento de distribuci贸n de especies (MDE), sensores remotos y sistemas de informaci贸n geogr谩fica (SIG). Se utiliz贸 el software Maxent, un programa de modelamiento basado en el principio de m谩xima entrop铆a, para obtener la distribuci贸n potencial presente del algarrobo, as铆 como la distribuci贸n potencial futura (para el a帽o 2050) bajo dos escenarios RCP 2,6 y 8,5, resultando en un inesperado aumento en la potencialidad del norte peruano para albergar la especie. Para conocer la din谩mica de los bosques secos en cuanto a cambios en cobertura vegetal, frecuencia de incendios y fragmentaci贸n del paisaje se utilizaron herramientas SIG y de teledetecci贸n (como el NDVI) para realizar un an谩lisis espacial y multitemporal, dando como resultado variaciones en la cobertura vegetal, pero que tienden a la reducci贸n de la vegetaci贸n hacia los 煤ltimos a帽os. Adem谩s, se evidencia una ampliaci贸n de la frontera agr铆cola debido principalmente a la deforestaci贸n. Por otra parte, no se puede omitir el rol de los eventos del ENSO en una zona como esta, pues sus efectos influyen en la regeneraci贸n de sus bosques. El trabajo de campo consisti贸 en dos partes esenciales: en primer lugar, obtener el 铆ndice de valor de importancia (IVI) del algarrobo en el bosque seco. El m茅todo de muestreo realizado fue el punto 鈥 centro 鈥 cuadrado, obteniendo un valor de 53,01 para el algarrobo, adem谩s de conocer la composici贸n flor铆stica del bosque, tomando como referencia principal el ACR Huacrupe. En segundo lugar, se aplicaron encuestas y entrevistas a actores clave, guardaparques y a la poblaci贸n local, quienes confirmaron la importancia de la especie para el mantenimiento de los bosques secos y como aporte y hasta sustento econ贸mico de diversas comunidades, as铆 como la preocupante situaci贸n de la deforestaci贸n, principalmente ilegal para fines comerciales, degradaci贸n y continua reducci贸n de los 谩rboles de algarrobo.On our planet, much of the continental area has been forested for millions of years. In Peru, the coast, highlands and jungle, have large forests, which together occupy 51% of the territory. Dry forests are characteristic ecosystems of the northern coast of Peru, and its key species Prosopis pallida, which represents not only an ecological but also economic value to communities surrounding these ecosystems. This research focuses on the forests of Lambayeque, being defined as representations of dry forests of carob tree those located in the Pomac Forest Historical Sanctuary, the ACP Chaparr铆 and ACR Huacrupe La Calera. Currently, it is clear that deforestation is the strongest cause of the reduction of many forest species. This coupled with the rapid changes in land use, forest fires and climate change are affecting many human communities and populations of animals and plants. One species that is threatened by these factors is, precisely, carob tree, so conservation along the dry forest ecosystem in its fullness is a priority. Therefore, the objective of this thesis is to identify and propose what strategies are most appropriate to conserve and manage the dry forests in an integrated manner so that resources and services offered by these ecosystems could be valorized. A methodology based on conservation biogeography, which included methods of species distribution modeling (MDE), remote sensing and geographic information systems (GIS), was worked. The Maxent software, a modeling program based on the principle of maximum entropy, for the present potential of the carob tree distribution, and its potential future distribution (2050) under two scenarios RCP 2,6 and 8,5 was used, resulting in an unexpected increase in the potential of northern Peru to host the species. To understand the dynamics of dry forests in terms of changes in land cover, fire frequency and landscape fragmentation, GIS tools and remote sensing methods (such as NDVI) were used to perform a spatial and multi-temporal analysis, resulting in variations in coverage plant, but they tend to reduce the vegetation to recent years. Furthermore, there is a clear expansion of the agricultural frontier, mainly due to deforestation. Moreover, one cannot ignore the role of ENSO events in an area like this, since their effects influence the regeneration of forests. The field work consisted of two main parts. In first place, to obtain the importance value index (IVI) of the carob tree dry forest. The sampling method was the point 鈥 centered 鈥 quarter, obtaining a value of 53,01 for the carob tree, besides knowing the floristic composition of the forest, taking as main reference the ACR Huacrupe. In second place and finally, surveys and interviews with key players, park rangers and local people applied who confirmed the importance of the species to the maintenance of dry forests and as a contribution and economic support to various communities as well as the worrying situation of deforestation, illegal primarily for commercial purposes, habitat fragmentation, degradation and continuous reduction of carob trees.Tesi

    Desarrollo de papeles biocativos por injerto de mol茅culas espec铆ficas en celulosa

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    Tesis (DCI)--FCEFN-UNC, 2019En la presente tesis se presenta el desarrollo de papeles bioactivos con potencial aplicaci贸n en el envasado activo de alimentos. Para tal fin, se propuso el injerto de eugenol, un compuesto de origen natural con propiedades antimicrobiana, antioxidante y repelente de insectos, en celulosa, utilizando 谩cido policarbox铆lico como agente ligante. Con el objetivo de evaluar la escalabilidad del proceso propuesto, se estudiaron distintas tecnolog铆as de curado, tales como calentamiento por convecci贸n, infrarrojo, microondas y conducci贸n. En todos los casos, se analizaron la influencia de las variables operativas sobre el avance de la reacci贸n y propiedades finales del papel preparado, utilizando un dise帽o de experimentos Doehlert para elegir las experiencias a realizar, y analizando los resultados mediante metodolog铆a de superficie de respuesta y an谩lisis estad铆stico ANOVA. Se pudo comprobar que la reacci贸n de injerto de eugenol en papel comercial se produjo con 茅xito en todas las tecnolog铆as estudiadas. Asimismo, se encontraron las condiciones 贸ptimas de reacci贸n para cada una de las tecnolog铆as, para lo cual se busc贸 un compromiso entre el avance de la reacci贸n y las propiedades finales del material (mec谩nicas y color). A partir de estas condiciones, se prepararon papeles y se realiz贸 una caracterizaci贸n m谩s espec铆fica para su aplicaci贸n como envase de alimentos comparando los papeles modificados con el papel virgen. Se analizaron las propiedades mec谩nicas por ensayo de tracci贸n, rasgado y punzonado y se midi贸 la absorci贸n de agua y la capacidad de degradaci贸n. Por otro lado, las propiedades bioactivas analizadas fueron la actividad antioxidante, antimicrobiana, repelente e insecticida de gorgojos (T. castaneum y R. dominica). Una vez probado que el papel modificado presenta buenas caracter铆sticas f铆sicas y bioactivas para su posible aplicaci贸n en el envasado de alimentos, se realizaron prototipos de envasado para harina, como alimento representativo de alimentos derivados de cereales, susceptibles al ataque de plagas. En este estudio se analiz贸 la migraci贸n de reactivos, propiedades organol茅pticas y conservaci贸n del alimento, arrojando resultados promisorios para la industria de envases de alimentos. Finalmente, se realiz贸 una comparaci贸n de las tecnolog铆as de curado ensayadas, analizando diferentes aspectos como avance de reacci贸n, propiedades finales, apariencia, tiempo de reacci贸n, consumo de energ铆a, entre otros, como as铆 tambi茅n disponibilidad y uso de estas tecnolog铆as a escala industrial, seleccionando la tecnolog铆a de conducci贸n como la m谩s adecuada para una propuesta de escalado industrial.Fil: Muratore, Florencia. Universidad Nacional de C贸rdoba. Facultad de Ciencias Exactas, F铆sicas y Naturales; Argentina.Fil: Muratore, Florencia. Consejo Nacional de Investigaciones Cient铆ficas y T茅cnicas. Instituto de Investigaci贸n y Desarrollo en Ingenier铆a de Procesos y Qu铆mica Aplicada; Argentina

    Does international patent collaboration have an effect on entrepreneurship?

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    .Entrepreneurship is one of the main pillars of growth in any economy. Achieving a high rate of entrepreneurship in a region has become the priority objective of governments and firms. However, in many cases, new firm creation is conditioned by relations or collaboration in innovation with agents from other countries. Previous literature has analyzed the mechanisms that foster entrepreneurship. This paper attempts to shed light on the influence of international patent collaboration (IPC) on entrepreneurial activity at country level taking into account the timing of this relationship. An empirical study is proposed to verify whether IPC leads to greater entrepreneurship and to analyze the gestation period between international patenting actions and firm creation. Using the Generalized Method of Moments, the two hypotheses proposed were tested in a data panel of 30 countries for the period 2005鈥2017. Results show the influence of IPC in promoting entrepreneurship in the same year, but especially in the following year. The study offers implications for entrepreneurs and public agents. IPC affects the integration and interaction of international agents in a country, favors the production of new knowledge, and increases positive externalities in a territory. All this facilitates the creation of new companies with a high innovative component.S

    How Does Reciprocity Affect Undergraduate Student Orientation towards Stakeholders?

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    5987Nowadays, students are more aware of the impact of companies on their stakeholders and the need for properly handling their expectations to operationalize corporate social responsibility. Nevertheless, little is known about how certain individual traits may relate to their stance on the issue. This exploratory research contributes to stakeholder theory by analysing the e ect of the individual鈥檚 decision-making process, including the consideration of their social preferences, on their orientation toward stakeholder management. Here, we draw upon a theoretical model for resource-allocation decision-making consisting of reciprocal and non-reciprocal components. Our data, from undergraduate students enrolled in di erent degrees, were collected through a questionnaire and two social within-subject experiments (ultimatum and dictator games). Thus, our results show that the presence of a reciprocal component when decisions are made is positively linked to an instrumental orientation toward stakeholders. In addition, a greater non-reciprocal component in the decision-making process corresponds to a more normative orientation.S

    Introduction to Special Issue 鈥淎dvances in Sustainability-Oriented Innovations鈥

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    8836This Special Issue focuses on the study of Sustainability-Oriented Innovations (SOIs). Our purpose is to shed light on the SOIs literature regarding their determining factors, implications and new challenges for the future. In this editorial, we are delighted to present the three papers included in this Special Issue. Each of them tackles di erent issues related to SOIs having important academic and managerial implications. Two papers analyze the influence of SOIs on urban development and resource productivity, respectively, and the third studies SOIs determinants, in particular, cooperation networks. Moreover, two of the papers analyze SOIs considering territory (cities or countries) as their unit of analysis while the third focuses on firms. This denotes that SOIs鈥 actions are important whatever the level of analysis and as either a determinant or a consequence.S

    Analysis of reliable deployment of TDOA local positioning architectures

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    .Local Positioning Systems (LPS) are supposing an attractive research topic over the last few years. LPS are ad-hoc deployments of wireless sensor networks for particularly adapt to the environment characteristics in harsh environments. Among LPS, those based on temporal measurements stand out for their trade-off among accuracy, robustness and costs. But, regardless the LPS architecture considered, an optimization of the sensor distribution is required for achieving competitive results. Recent studies have shown that under optimized node distributions, time-based LPS cumulate the bigger error bounds due to synchronization errors. Consequently, asynchronous architectures such as Asynchronous Time Difference of Arrival (A-TDOA) have been recently proposed. However, the A-TDOA architecture supposes the concentration of the time measurement in a single clock of a coordinator sensor making this architecture less versatile. In this paper, we present an optimization methodology for overcoming the drawbacks of the A-TDOA architecture in nominal and failure conditions with regards to the synchronous TDOA. Results show that this optimization strategy allows the reduction of the uncertainties in the target location by 79% and 89.5% and the enhancement of the convergence properties by 86% and 33% of the A-TDOA architecture with regards to the TDOA synchronous architecture in two different application scenarios. In addition, maximum convergence points are more easily found in the A-TDOA in both configurations concluding the benefits of this architecture in LPS high-demanded applicationS

    A new index of resilience applicable to external pulse-disturbances that considers the recovery of communities in the short term

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    .Resilience is a key concept in the study of the recovery of ecosystems affected by disturbances. Currently, there are numerous indices to measure resilience, but many of them do not show the accuracy of the resilience value or the behaviour of ecological parameters in the face of disturbances. New approaches and technologies enable large amounts of information to be obtained, facilitating the proposal of new resilience indices that work consistently and intuitively for a wide variety of ecological response variables under different scenarios after pulse-disturbances. In this study, we propose and verify a new resilience index, comparing its performance with others previously published. We validated the performance of the new index using real data based on field measurements of changes in soil bacterial OTUs diversity and abundance after a wildfire. The new resilience index provided an automatic and robust functional classification of the behaviour of ecosystems after disturbances, supported by a bootstrap analysis. We identified 5 scenarios of ecosystem resilience performance according to their behaviour after a pulse-disturbance: resilient, non-resilient, recovering, rebound, and continuing.S

    Relaciones sociales y creatividad en la empresa: la importancia de la calidad de las interacciones del empleado con su entorno m谩s cercano

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    pp. 1-16La creatividad se est谩 convirtiendo en un fen贸meno de especial importancia para las organizaciones. Por ello, existe un inter茅s creciente por comprender cu谩les son los factores responsables del rendimiento creativo en los entornos laborales. A pesar de ello, todav铆a existen lagunas importantes en la literatura sobre la influencia del liderazgo y del comportamiento de los grupos en la creatividad. Con el fin de aportar nueva evidencia emp铆rica al respecto, el objetivo del presente trabajo consiste en analizar c贸mo influyen las relaciones de intercambio que mantiene el empleado con su superior inmediato y con su grupo de trabajo en la creatividad que pone de manifiesto.S

    Interactive Sonic Environments: Sonic artwork via gameplay experience

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    The purpose of this study is to investigate the use of video-game technology in the design and implementation of interactive sonic centric artworks, the purpose of which is to create and contribute to the discourse and understanding of its effectiveness in electro-acoustic composition highlighting the creative process. Key research questions include: How can the language of electro-acoustic music be placed in a new framework derived from videogame aesthetics and technology? What new creative processes need to be considered when using this medium? Moreover, what aspects of 'play' should be considered when designing the systems? The findings of this study assert that composers and sonic art practitioners need little or no coding knowledge to create exciting applications and the myriad of options available to the composer when using video-game technology is limited only by imagination. Through a cyclic process of planning, building, testing and playing these applications the project revealed advantages and unique sonic opportunities in comparison to other sonic art installations. A portfolio of selected original compositions, both fixed and open are presented by the author to complement this study. The commentary serves to place the work in context with other practitioners in the field and to provide compositional approaches that have been taken

    Balancing the urban stomach: public health, food selling and consumption in London, c. 1558-1640

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    Until recently, public health histories have been predominantly shaped by medical and scientific perspectives, to the neglect of their wider social, economic and political contexts. These medically-minded studies have tended to present broad, sweeping narratives of health policy's explicit successes or failures, often focusing on extraordinary periods of epidemic disease viewed from a national context. This approach is problematic, particularly in studies of public health practice prior to 1800. Before the rise of modern scientific medicine, public health policies were more often influenced by shared social, cultural, economic and religious values which favoured maintaining hierarchy, stability and concern for 'the common good'. These values have frequently been overlooked by modern researchers. This has yielded pessimistic assessments of contemporary sanitation, implying that local authorities did not care about or prioritise the health of populations. Overly medicalised perspectives have further restricted historians' investigation and use of source material, their interpretation of multifaceted and sometimes contested cultural practices such as fasting, and their examination of habitual - and not just extraordinary - health actions. These perspectives have encouraged a focus on reactive - rather than preventative - measures. This thesis contributes to a growing body of research that expands our restrictive understandings of pre-modern public health. It focuses on how public health practices were regulated, monitored and expanded in later Tudor and early Stuart London, with a particular focus on consumption and food-selling. Acknowledging the fundamental public health value of maintaining urban foodways, it investigates how contemporaries sought to manage consumption, food production waste, and vending practices in the early modern City's wards and parishes. It delineates the practical and political distinctions between food and medicine, broadly investigates the activities, reputations of and correlations between London's guild and itinerant food vendors and licensed and irregular medical practitioners, traces the directions in which different kinds of public health policy filtered up or down, and explores how policies were enacted at a national and local level. Finally, it compares and contrasts habitual and extraordinary public health regulations, with a particular focus on how perceptions of and actual food shortages, paired with the omnipresent threat of disease, impacted broader aspects of civic life
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