170,736 research outputs found
NUEVOS PROTOCOLOS PARA LA CRIOCONSERVACIÓN DE ESPERMATOZOIDES DE MACHO CABRÍO
No full textEl objetivo de trabajo es el desarrollo de un protocolo para la adición de ciclodextrinas saturadas de colesterol (clc) al semen de caprino, con el fin de modificar la membrana plasmática de los espermatozoides y mejorar su calidad post-descongelación.Tomás Almenar, C. (2007). NUEVOS PROTOCOLOS PARA LA CRIOCONSERVACIÓN DE ESPERMATOZOIDES DE MACHO CABRÍO. Universitat Politècnica de València. https://riunet.upv.es/handle/10251/12583Archivo delegad
Arte contemporáneo y sociedad. La galería como agente cultural en Valencia
No full textImportancia que tiene en Valencia el papel de la galería como nexo entre la sociedad y el arte contemporáneo.García Almenar, C. (2009). Arte contemporáneo y sociedad. La galería como agente cultural en Valencia. Universitat Politècnica de València. https://riunet.upv.es/handle/10251/14490Archivo delegad
Thematic urban ecosystem accounts - challenges, lessons and ways forward
No full textEcosystem accounts can serve as a framework to monitor changes not only in natural ecosystems, but also in anthropogenic ones such as urban ecosystems. Urban ecosystems are both drivers of global and local biodiversity change, and the primary living spaces for humans. This makes urban ecosystem accounts a valuable tool for revealing trade-offs between multiple benefits and for in-forming diverse sets of policies at various spatial levels. Developing a global urban ecosystem ac-counting framework could also help enhance our understanding of urban ecosystems and their sustainable management. To introduce the topic of the session on “Advancing the application of ecosystem accounting to urban ecosystems”, we discuss the potential development of a global urban ecosystem accounting framework based on SEEA-EA thematic accounts. Moving from a review of the literature, we outline key challenges in thematic urban ecosystem accounting, and present potential solutions based on lessons and approaches gathered from past experiences. Our analysis shows that urban ecosystem accounts share challenges with accounts of most ecosystems. However, challenges related to ecosystem extent and condition accounts are mainly specific to urban or anthropogenic ecosystems. Various approaches have been used to define and classify urban ecosystems, but there is no global consensus in terms of delimitation and classification yet, at least from an accounting perspective. The analysis also highlights that policy uses of urban ecosystem accounts are varied but often unclear, with local policy push potentially lacking in part due to this issue. As a final reflection, we note that urban ecosystem challenges are interrelated, and some are dependent on each other. This reflection sets the stage for the ESP session, where current conceptual, methodological, and operational advances (and strategies) for addressing these challenges will be discussed
Quantification and mapping of regulating and provisioning services in urban areas making use of a system dynamics model
No full textOral Presentation
Abstract:
There is a growing evidence that the use of statistical, process-based, and mechanistic models can provide robust information for the quantification and mapping of provisioning and regulating services. These models can allow identification and relation of main factors of biophysical structures and processes, taking into account how the condition of ecosystems or living features (e.g. health conditions of trees) could increase or decrease the supply of ecosystem services (ES). However, they i) usually assume that conditions do not change over time; ii) rarely consider causal loop interactions among biophysical structures, processes and human actions; iii) do not model multiple ES at once. In this research, we present a system dynamics modelling approach to quantify and map several regulation and provisioning services and disservices simultaneously supplied by urban nature-based solutions, which acknowledges temporal changes in the system. To illustrate the approach, we develop and present the results of an urban forest model applied to Valdebebas Park (Madrid, Spain). Five regulating services (carbon sequestration, temperature regulation, air pollutant filtration, and water flow maintenance), one provisioning service (plant material for direct use or processing), and one provisioning disservice (plant residues for landfill or waste treatment) were quantified and mapped in biophysical units. The model includes morbidity dynamics of trees triggered by their location (street vs open spaces), lack of water, and waterlogging, as well as the influence of human management. The results show the potential of system dynamics models to quantify bundles of ES in a spatio-temporally explicit form and their usefulness to inform decision making in urban interventions.
Key words: System Dynamics; Nature-based Solutions; Ecosystem Services; Ecosystem Disservices
Modelling Benefits and Costs of Urban Forest: Application to Valdebebas Park (Madrid, Spain)
No full textOral Presentation
Abstract:
Process-based models are gaining relevance for the quantification of benefits and costs derived from urban nature-based solutions (e.g. urban forests, green roofs) as a way to inform decision makers. We developed a system dynamics approach to quantify the net environmental and economic benefits of urban nature-based solutions. Based on our system dynamics approach, we present a proof-of-concept model of urban forest to quantify their net economic benefits, which was applied to a zone of Valdebebas Park (Madrid, Spain). The proof of concept model quantifies three ecosystem services (carbon sequestration, temperature and humidity regulation, and potential wood provision) and takes into account investment costs, and two operational costs (re-planting dead trees, and waste treatment of plant residues) in a spatio-temporal explicit form. The model uses a regular grid of cells of 100x100 meters and calculates ecosystem services (benefits) and costs at a monthly temporal resolution. For the application to Valdebebas Park, we modelled the ecosystems services (benefits) and operational costs in the form of biophysical outputs for 50 years. Later, we converted the biophysical outputs into monetary units making use of benefit transfer functions and aggregating outputs into yearly time steps. As part of the model, tree death is included making use of binomial probability functions, which incorporates stochasticity into the model. As a result of the application, advantages and current limitations of the model were discussed as well as its usefulness for decision making.
Key words: System Dynamics; MIMES; Nature-based Solutions; Ecosystem Services; Biophysical Valuation; Monetary Valuatio
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
A system dynamics model of urban forests to assess ES trade-offs and synergies in biophysical and monetary unit.
No full textOral Presentation
Abstract
Enhancing urban ecosystem services through the implementation of nature-based solutions
(NBS) in cities can support a further integration of environmental objectives into urban
planning. However, how to implement NBS to reduce the distance between urban planning
and practical urban sustainable management and development remains an open question. In
this study, we use a system dynamics framework to analyse the contribution of NBS,
specifically urban forests, to address environmental urban challenges. An initial model of
urban forest was developed to study i) regulation of temperature and humidity; ii) regulation of chemical conditions; and iii) provision of materials by respectively modelling changes in
physiological equivalent temperature, carbon sequestration, and exploitable above ground
biomass. The economic benefits (in terms of these services) and costs were then computed
under several management and development scenarios representing alternative management
types (i.e. trimming, harvesting) and built densities (i.e. low to high built density). As part of
the modelling framework, several other ecosystem services, biophysical indicators, and their
main socio-environmental factors and processes are identified and related to key urban
challenges. The tested model shows the potential of urban forests’ for supplying ecosystem
services and identifies different trade-offs on the regulation of chemical conditions and
temperature depending on the intensities of wood harvesting and urban conditions (e.g.
urban vs periurban), which together with the consideration of costs inform about economic
benefits or loss. The use of a system dynamics approach applied to the modelling of NBS
shows to be a valuable decision support solution to allow understanding how the concept of
ecosystem services can be valuable for the planning and management of green spaces.
Keywords: System Dynamics; MIMES; Nature-based Solutions; Ecosystem Services; Monetary
Valuatio
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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