Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
1,031
result(s) for
"Bonet, J. A."
Sort by:
Social Entrepreneurship in Non-Profit and Profit Sectors : Theoretical and Empirical Perspectives
This volume examines the theoretical and empirical landscape of social entrepreneurship in both non-profit and profit sectors. It extends the traditional view of social entrepreneurship to include the environmental and institutional factors that affect the emergence of social entrepreneurship activities, such as formal laws, regulations, procedures and informal institutions. The editors aim to provide evidence and increased understanding of this growing phenomenon. Social Entrepreneurship is gaining recognition as a key element of economic and social development. It embraces a wide set of situations with a broad scope of activities in for-profit and non-profit organizations interested in social performance and/or in economically profitable performance, with an emphasis on achieving social aim. In the strict sense, social entrepreneurship corresponds to entrepreneurs whose main concern is to achieve social objectives rather than to obtain personal financial profits. However, there is still much to be learned about the dynamics and processes of social entrepreneurship. The current literature in the field has tended to focus on psychological experiences and personal characteristics, or on organizational perspectives such as resources, capabilities and leadership. This book intends to provide theoretical frameworks and empirical studies to this very new and broad field. Specifically, this book provides a collection of contemporary research in the following topics: How to create opportunity through social innovation How to detect entrepreneurial opportunity to meet social needs How to develop social entrepreneurship, while still seeking profits How to discover opportunities for different forms of social entrepreneurship Featuring contributions from around the world, this book is a valuable source for students, academics, researchers, policy makers, and professionals in the area of social entrepreneurship.
Book
Pattern of Tuber melanosporum extramatrical mycelium expansion over a 20-year chronosequence in Quercus ilex-truffle orchards
Successful cultivation of black truffle (
Tuber melanosporum
) requires a long-term investment and the maintenance of the symbiosis throughout its preproductive and productive years. Monitoring the symbiosis over time is challenging, as it requires methods that can detect the belowground proliferation of the fungus associated with its host tree. In this study, we used a chronosequence design to study the expansion pattern of this fungus as the host tree grows. We hypothesize that this expansion can be estimated by monitoring
T. melanosporum
DNA from soil beneath host trees of different ages (3, 5, 7, 10, 14, and 20 years old) and at different distances from the trunk of the trees (40, 100, and 200 cm). We also wished to evaluate the presences of
Tuber brumale
and
Tuber indicum
, potentially problematic truffle species, in these plantations. To detect the mycelium of
T. melanosporum
in these soils, we extracted DNA and performed polymerase chain reaction (PCR) with
Tuber
species-specific primers, and to estimate DNA amount, we measured relative band intensities from the amplicons in agarose gels. Both age and distance were related to
T. melanosporum
DNA quantity, which was more abundant in the oldest age classes, reaching a plateau in 5–7 years. At 40 cm from the tree, there were no differences in
T. melanosporum
DNA amounts in orchards of different ages, but at 100 and 200 cm, younger orchards had less
T. melanosporum
DNA. We did not detect DNA from
T. brumale
or
T. indicum
in any of our samples.
Journal Article
Weed management and irrigation are key treatments in emerging black truffle (Tuber melanosporum) cultivation
Interest in conversion of marginal agricultural lands to small oak woodlands for the production of black truffles (
Tuber melanosporum
Vittad.) is increasing in the native black truffle areas of France, Spain and Italy as well as suitable or amended sites throughout the world due to high economic returns for gastronomically valuable truffles. Successful long-term management of a perennial plantation replacing an annual crop requires understanding the system in all phases of the life cycle, and in the case of truffles this involves understanding the interactive growth of the aboveground host and the belowground symbiotic ectomycorrhizal fungus whose fruitbody is the desired truffle. Here we focus on the pre-production phase, 4 years after establishing the truffle-oak plantation and prior to truffle production. We tested the influence of weed control, irrigation and fertilizer, each at 3 levels, on plant growth and ectomycorrhizal proliferation in three truffle-oaks plantations in northeast Spain. Results show that adequate weed control improves root and shoot dry weight while fertilizer and irrigation treatments did not influence plant growth. The low dose of irrigation (50% of the estimated water deficit for the site) and glyphosate weed control both increased total root tips/plant and
T. melanosporum
colonized tips (ectomycorrhizae) by approximately two-fold, compared to control treatments. Distribution of the ectomycorrhizae within the soil profile was significantly influenced by the low dose irrigation treatment, with increases observed in the 10–20 cm and the 20–30 cm deep layers compared to the control and high irrigation treatments. Four years after planting,
T. melanosporum
remained the dominant fungal symbiont, despite the presence of 14 other ectomycorrhizal morphotypes from these sites.
Journal Article
The Filter Imager SuFI and the Image Stabilization and Light Distribution System ISLiD of the Sunrise Balloon-Borne Observatory: Instrument Description
We describe the design of the
Sunrise
Filter Imager (SuFI) and the Image Stabilization and Light Distribution (ISLiD) unit onboard the
Sunrise
balloon borne solar observatory. This contribution provides the necessary information which is relevant to understand the instruments’ working principles, the relevant technical data, and the necessary information about calibration issues directly related to the science data.
Journal Article
The Imaging Magnetograph eXperiment (IMaX) for the Sunrise Balloon-Borne Solar Observatory
The Imaging Magnetograph eXperiment (IMaX) is a spectropolarimeter built by four institutions in Spain that flew on board the
Sunrise
balloon-borne solar observatory in June 2009 for almost six days over the Arctic Circle. As a polarimeter, IMaX uses fast polarization modulation (based on the use of two liquid crystal retarders), real-time image accumulation, and dual-beam polarimetry to reach polarization sensitivities of 0.1%. As a spectrograph, the instrument uses a LiNbO
3
etalon in double pass and a narrow band pre-filter to achieve a spectral resolution of 85 mÅ. IMaX uses the high-Zeeman-sensitive line of Fe
i
at 5250.2 Å and observes all four Stokes parameters at various points inside the spectral line. This allows vector magnetograms, Dopplergrams, and intensity frames to be produced that, after reconstruction, reach spatial resolutions in the 0.15 – 0.18 arcsec range over a 50×50 arcsec field of view. Time cadences vary between 10 and 33 s, although the shortest one only includes longitudinal polarimetry. The spectral line is sampled in various ways depending on the applied observing mode, from just two points inside the line to 11 of them. All observing modes include one extra wavelength point in the nearby continuum. Gauss equivalent sensitivities are 4 G for longitudinal fields and 80 G for transverse fields per wavelength sample. The line-of-sight velocities are estimated with statistical errors of the order of 5 – 40 m s
−1
. The design, calibration, and integration phases of the instrument, together with the implemented data reduction scheme, are described in some detail.
Journal Article
The Sunrise Mission
The first science flight of the balloon-borne
Sunrise
telescope took place in June 2009 from ESRANGE (near Kiruna/Sweden) to Somerset Island in northern Canada. We describe the scientific aims and mission concept of the project and give an overview and a description of the various hardware components: the 1-m main telescope with its postfocus science instruments (the UV filter imager SuFI and the imaging vector magnetograph IMaX) and support instruments (image stabilizing and light distribution system ISLiD and correlating wavefront sensor CWS), the optomechanical support structure and the instrument mounting concept, the gondola structure and the power, pointing, and telemetry systems, and the general electronics architecture. We also explain the optimization of the structural and thermal design of the complete payload. The preparations for the science flight are described, including AIV and ground calibration of the instruments. The course of events during the science flight is outlined, up to the recovery activities. Finally, the in-flight performance of the instrumentation is discussed.
Journal Article
First Implementation Of Phase Diversity At Themis
Phase diversity techniques are robust post-processing tools for image enhancement and correction of telescopic and atmospheric induced aberrations. We present results obtained applying the Partitioned Phase-Diverse Speckle (PPDS) technique to images acquired at THEMIS. We also present an image quality estimator based on image power spectrum content we developed in order to automatically evaluate the results of large amount of data.
Journal Article
Infrared photometry of solar active regions
Simultaneous time series of broad-band images of two active regions close to the disk center were acquired at the maximum (0.80Μm) and minimum (1.55Μm) continuum opacities. Dark faculae are detected in images obtained as weighted intensity differences between both wave-length bands. The elements of quiet regions can be clearly distinguished from those of faculae and pores in scatter plots of brightness temperatures. There is a smooth transition between faculae and pores in the scatter plots. These facts are interpreted in terms of the balance between the inhibition of convective energy transport and the lateral radiative heating.[PUBLICATION ABSTRACT]
Journal Article
The Sun at high resolution: first results from the Sunrise mission
The Sunrise balloon-borne solar observatory consists of a 1m aperture Gregory telescope, a UV filter imager, an imaging vector polarimeter, an image stabilization system and further infrastructure. The first science flight of Sunrise yielded high-quality data that reveal the structure, dynamics and evolution of solar convection, oscillations and magnetic fields at a resolution of around 100 km in the quiet Sun. Here we describe very briefly the mission and the first results obtained from the Sunrise data, which include a number of discoveries.
Journal Article
Time and dose of irrigation impact Tuber melanosporum ectomycorrhiza proliferation and growth of Quercus ilex seedling hosts in young black truffle orchards
In Mediterranean climate, young truffle-oak orchards are subjected to drought episodes that can compromise the development of Tuber melanosporum. We investigated the responses of T. melanosporum to water supply in three periods: May to July, August to October, and May to October. In each period, five water doses were established: 0, 25, 50, 75, and 100 % of the reference evapotranspiration (ETo). Five orchards were planted with Quercus ilex inoculated with T. melanosporum, and in each orchard, we arranged a two-factorial design with irrigation period and irrigation dose as main factors to test their combined effects on the development of both T. melanosporum and Q. ilex after 3 years in the field. Irrigation period significantly interacted with irrigation doses for the absolute presence per seedling of T. melanosporum mycorrhizae. Irrigation in May–July increased significantly T. melanosporum colonization in seedlings irrigated with 50 % ETo dose compared to the 0 % ETo dose. A similar pattern with smaller differences in means was observed in August–October period, but the irrigation doses did not change T. melanosporum colonization when we watered from May to October. We found ectomycorrhizae different from T. melanosporum in 51 % of the seedlings studied, but their presence was marginal. Our results suggest that a moderate irrigation dose promotes seedling growth and number of fine root tips per unit of fine root length, which may be potentially colonized by T. melanosporum.
Journal Article