Free-form, form finding and anisotropic grid shell

p. 966-876The new geometrical developments open new perspectives for free-form design, making it possible to escape from planar triangular or quadrilateral discretizations. Recent advances in theory algorithms allow for the discretization of any surface using only single curvature panels thus allowing the realisation of smooth double curvature glazed envelops of any form. Grid shell structures usually present a nearly in plane uniform behaviour, but previous realisations have shown that grid shells can be designed also according to an anisotropic inplane arrangement. The control of principal direction and the fine tuning of the stiffness of the different structural elements (arcs, cables etc.) is a tool for adjusting the form-finding thus controlling the resulting geometry. Moreover, the form-finding can also be performed without researching a constant stress (self weight); in this case an even wider range of forms become possible. These new geometrical and structural approaches have been coupled together and tested in re-designing, as a case study, the glazed roof of the Neumunster Abbey in Luxembourg. Such approach allowed for the conception of an efficient structure supporting a smooth double curvature glass skin, made out of only single curvature panels, perfectly coherent with the perimeter of the courtyard i.e. matching all the edges without any gaps.Baldassini, N.; Raynaud, J. (2010). Free-form, form finding and anisotropic grid shell. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/696

North, South, East and West: The Environmental Approach to Transparent Design

Architecture has always been interested in transparency but this characteristic hasstrong implications for energy performance. For many years architecture hasneglected this factor but today, in a time when society has developed an awarenessof the carbon footprint, architecture must restructure its approach and process.Transparency is still possible but its implications must be taken into considerationfrom the very beginning of the process: when façades are designed with respectsolar exposure and the advantages of internal natural ventilation, transparencybecomes sustainable in terms of energy balance in addition to contributing toarchitectural expression

Regional characterization of the structure and productivity of the vegetation of the Puna using MODIS images

La Puna es una región semiárida ubicada por encima de los 3300 m.s.n.m. en el noroeste argentino. Si bien existen descripciones florísticas parciales de la vegetación en el área, no existen trabajos que describan su fisonomía y su funcionamiento, aspectos claves para el manejo de la vegetación de la región. El objetivo de este trabajo fue cartografiar los diferentes tipos fisonómicos presentes y caracterizar su funcionamiento a partir de la estimación de la productividad primaria neta aérea (PPNA) en un área de 69210 km2 en las provincias de Salta y Jujuy. La aproximación metodológica combinó la utilización de datos provistos por sensores remotos, modelos biofísicos para estimar la productividad y censos fisonómico-florísticos. De las clases vegetadas, las estepas arbustivas (Estepa arbustiva densa y Estepa arbustiva rala) fueron las que ocuparon mayor proporción del territorio analizado, cubriendo entre ambas el 45% aproximadamente, mientras que las Estepas graminosas densas fueron las menos representadas, cubriendo poco más del 1%. Entre las clases no vegetadas el Suelo desnudo fue la clase más extendida, cubriendo aproximadamente 30% del área, seguida por la clase Salar, que ocupó 8.15%. El tipo fisonómico más productivo fue la Estepa graminosa densa (PPNA = 3900 kg MS.ha-1 .año-1), mientras que la Estepa arbustiva rala presentó la menor productividad (PPNA = 472 kg MS.ha-1.año-1). Los restantes tipos fisonómicos no superaron en promedio los 1000 kg MS.ha-1.año-1.The Puna is a semi-arid region located over 3300 m.a.s.l. in the northwestern portion of Argentina. Previous regional studies in Puna focused on the description of the floristic heterogeneity of relatively small portions of the territory. No integrative descriptions of the phisiognomy and functioning of the Puna ecosystems, two keys aspects for development of management actions, have been produced. In this article we generated a map of physonogmic types and we characterized above-ground net primary production (ANPP) of the different classes defined over an area of 69210 km2. The methodology to characterize vegetation structure (physiognomic units) combines remotely sensed data from MODIS sensor with field observations. Further, we applied biophysical models and satellite information to estimate ANPP. Among the classes with more than 5% of plant cover, shrub steppes (both sparse and dense) occuppied most of the area (45%). Dense grass steppes covered less than 1%. Bare soil covered most that 30% of the area, followed by Salt flats (8.15%). The most productive physiognomic type was the dense grass steppe (ANPP = 3900 kg DM.ha-1.year-1), while the sparse shrub steppe unit presented the lowest values (ANPP = 472 kg DM.ha-1.year-1). The remaining physiogmomic types presented ANPP values lower than 1000 kg DM.ha-1.year-1

Elementos conceptuales y metodológicos para la evaluación de impactos ambientales acumulativos (eiaac) en bosques subtropicales : el caso del este de salta, argentina

163-178Northern Argentina experienced an unprecedented deforestation rate of xerophitic forests as a consequence of agricultural expansion. In the Province of Salta, 26 percent of the forest were removed between 1977 and 2008. At the end of 2007, just before the No. 26331 Law of Native Forest Protection was voted by the Congress, the highest annual rate of deforestation was registered, reaching a value of 2.1 percent. Regarding this situation, indigenous people of Eastern Salta along with the "criollos" (local small ranchers) appealed to the National Supreme Court of Justice for legal protection. The Court requested the province to elaborate a Cumulative Environmental Effects Assessment (CEEA) regarding the process of logging and deforestation in four departments of Salta Province (San Martín, Rivadavia, Santa Victoria, and Orán). The aim of this work is to present a conceptual framework to conduct a CEEA in eastern Salta and to present the evidences and existing methodologies to characterize the impacts of deforestation. The conceptual framework suggested depends on the quantitative characterization of the changes in the provision level of key ecosystem services as a function of the stress and/or disturbance level (in this case deforestation). Based on the literature and our own data, the effects of deforestation on four key ecosystem services have been assessed: C dynamics, energy balance and greenhouse gases emissions, water dynamics and landscape structure. Deforestation produced emissions of 2000 t of CH 4, 200 t of N 2O, above 20 Gg of C/year, a 1.1 watt/m2 reduction in reflected radiation and 4400 TJ radiative energy emissions caused by deforestation fires, increases in the risk of soil salinization and landscape fragmentation. Considering these aspects of the structure and functioning of the ecosystems provides objective elements to evaluate management alternatives and to elaborate monitoring programmes. To consider such management and monitoring alternatives arises technical challenges but also institutional and political ones

Conceptual and Methodological Elements for Cumulative Environmental Effects Assessment (CEEA) in Subtropical Forests. The Case of Eastern Salta, Argentina

En el norte argentino se ha producido una fuerte expansión agropecuaria a costa del desmonte de bosques xerofíticos. En la Provincia de Salta, entre 1977 y 2008 se desmontó 26% del total de bosques existentes. A fines de 2007, frente a la inminente sanción de la Ley Nº 26331 de Presupuestos Mínimos de Protección Ambiental de los Bosques Nativos, se registra el valor más alto de la historia con una tasa de desmonte de 2.1%. Frente a esta situación, comunidades originarias y criollas del este de Salta presentaron un recurso de amparo a la Corte Suprema de Justicia de la Nación, la cual solicitó a esta provincia la elaboración de una Evaluación de Impacto Ambiental Acumulativo (EIAAc) de los procesos de tala y desmonte en 4 departamentos. Los objetivos de este trabajo son proponer un marco conceptual para la EIAAc en el este de Salta y presentar evidencias y metodologías disponibles para la caracterización de esos impactos a partir de datos propios y de la literatura. El marco conceptual propuesto se basa en la cuantificación de los cambios en los niveles de provisión de servicios ecosistémicos (SE) en función de los factores de estrés y perturbación más importantes. Se analizaron los efectos del desmonte sobre cuatro SE clave: dinámica del C, balance de energía y emisión de gases con efecto invernadero (GEI), dinámica del agua y estructura del paisaje. Los desmontes generan emisiones de C superiores a 20 Gg C/año, disminuciones en la reflectancia de 1.1 watt/m2, emisiones de 2000 t de CH4, 200 t de N2O y 4400 TJ de energía radiativa por fuegos, aumentos del riesgo de salinización de suelos y fragmentación del paisaje. La consideración de estos aspectos provee elementos objetivos para la evaluación de alternativas de manejo y la elaboración de planes de seguimiento. Esto plantea no sólo desafíos técnicos sino también institucionales y políticos.Northern Argentina experienced an unprecedented deforestation rate of xerophitic forests as a consequence of agricultural expansion. In the Province of Salta, 26% of the forest were removed between 1977 and 2008. At the end of 2007, just before the No. 26331 Law of Native Forest Protection was voted by the Congress, the highest annual rate of deforestation was registered, reaching a value of 2.1%. Regarding this situation, indigenous people of Eastern Salta along with the ocriollosp (local small ranchers) appealed to the National Supreme Court of Justice for legal protection. The Court requested the province to elaborate a Cumulative Environmental Effects Assessment (CEEA) regarding the process of logging and deforestation in four departments of Salta Province (San Martín, Rivadavia, Santa Victoria, and Orán). The aim of this work is to present a conceptual framework to conduct a CEEA in eastern Salta and to present the evidences and existing methodologies to characterize the impacts of deforestation. The conceptual framework suggested depends on the quantitative characterization of the changes in the provision level of key ecosystem services as a function of the stress and/or disturbance level (in this case deforestation). Based on the literature and our own data, the effects of deforestation on four key ecosystem services have been assessed: C dynamics, energy balance and greenhouse gases emissions, water dynamics and landscape structure. Deforestation produced emissions of 2000 t of CH4, 200 t of N2O, above 20 Gg of C/year, a 1.1 watt/m2 reduction in reflected radiation and 4400 TJ radiative energy emissions caused by deforestation fires, increases in the risk of soil salinization and landscape fragmentation. Considering these aspects of the structure and functioning of the ecosystems provides objective elements to evaluate management alternatives and to elaborate monitoring programmes. To consider such management and monitoring alternatives arises technical challenges but also institutional and political ones

Adherence issues related to sublingual immunotherapy as perceived by allergists

Objectives: Sublingual immunotherapy (SLIT) is a viable alternative to subcutaneous immunotherapy to treat allergic rhinitis and asthma, and is widely used in clinical practice in many European countries. The clinical efficacy of SLIT has been established in a number of clinical trials and meta-analyses. However, because SLIT is self-administered by patients without medical supervision, the degree of patient adherence with treatment is still a concern. The objective of this study was to evaluate the perception by allergists of issues related to SLIT adherence. Methods: We performed a questionnaire-based survey of 296 Italian allergists, based on the adherence issues known from previous studies. The perception of importance of each item was assessed by a VAS scale ranging from 0 to 10. Results: Patient perception of clinical efficacy was considered the most important factor (ranked 1 by 54% of allergists), followed by the possibility of reimbursement (ranked 1 by 34%), and by the absence of side effects (ranked 1 by 21%). Patient education, regular follow-up, and ease of use of SLIT were ranked first by less than 20% of allergists. Conclusion: These findings indicate that clinical efficacy, cost, and side effects are perceived as the major issues influencing patient adherence to SLIT, and that further improvement of adherence is likely to be achieved by improving the patient information provided by prescribers. © 2010 Scurati et al, publisher and licensee Dove Medical Press Ltd

Grid Shells

Con il termine di gusci a griglia (Grid Shells in inglese o Gitterschale in tedesco) si indicano quelle coperture costituite da una trama sottile di aste metalliche organizzate su superfici a doppia o semplice curvatura mediante maglie quadrangolari o triangolari. La struttura metallica è autoportante, indipendentemente dal manto di copertura il quale è sistematicamente costituito da lastre di vetro. La trasparenza e l’effetto di filigrana sono le caratteristiche peculiari di queste coperture e la loro esaltazione presuppone necessariamente un processo molto spinto di ottimizzazione della leggerezza strutturale la quale, a sua volta, richiede una accurata, non arbitraria, ricerca della forma