Collecting tortoises for the pet trade is one of the factors threatening species of Testudo in th... more Collecting tortoises for the pet trade is one of the factors threatening species of Testudo in the Mediterranean area. The collection of Testudo graeca graeca for pets is described in southeast Spain, where the main European population of this subspecies coincides with an area where keeping tortoises in captivity is a long-established custom. This present paper, based on inquiries made to children, reveals that this practice continues to be a common activity, and estimates a captive population in the order of tens of thousand of tortoises. Tortoises are collected as a result of chance encounters with wild animals by local inhabitants, and without any commercial objectives. The captive breeding and the release of tortoises without any institutional control is also common. These activities could be an important threat for the species. Implications for conservation are discussed and a critical review of the conservation strategies developed in relation to this threat (trade control and re-introduction programmes) are presented. We suggest that environmental education programmes are necessary to reduce casual collection and to change the social perception of tortoises as pets.
This study was carried out in response to the growing interest on household biogas digesters in L... more This study was carried out in response to the growing interest on household biogas digesters in Latin America, particularly in rural Andean communities. The aim was to compare the fixed dome and plastic tubular digester in terms of biogas production, cost and environmental impact, using the life cycle assessment methodology. Design and operational parameters, construction materials and implementation costs were based on our previous research and literature results for plastic tubular and fixed dome digesters, respectively. According to this analysis, the main advantage of the plastic tubular digester was its ease of implementation and handling, and lower investment cost compared to the fixed dome digester, which appeared to be more environmentally friendly.
Currently, the best way to reduce the mortality of cancer is to detect it and treat it in the ear... more Currently, the best way to reduce the mortality of cancer is to detect it and treat it in the earliest stages. Automatic decision support systems are very helpful in this task but their performance is constrained by different factors and sometimes it is difficult to find a method ...
In this article we want to assess the feasibility of using genetic algorithms as classifiers that... more In this article we want to assess the feasibility of using genetic algorithms as classifiers that could be used in clinical decision support systems, for urological diseases diagnosis in our case. The use of artificial neural networks is more common in this field, and we have previously tested their use with the same purpose. At the end of the document we compare the obtained results using genetic algorithms and two different artificial neural networks implementations. The obtained accuracy rates show that genetic algorithms could be a useful tool to be used in the clinical decision support systems field.
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference, 2011
In this paper, we show the results of a study in which we try to test the feasibility of using ra... more In this paper, we show the results of a study in which we try to test the feasibility of using radial basis functions neural networks (RBFs for short) in clinical decision support systems. We have implemented two instances of RBFs in order to diagnose possible prostate cancer cases from a clinical database. To give an idea about how good the results are, we follow a two-fold approach. On the one hand they are independently evaluated in terms of accuracy, sensitivity and specificity and on the other hand they are compared with the performance over the same database of a classifier widely applied to the medical field problems, as it is multi-layer perceptron (MLP). The experimental results show that RBFs are a useful tool to build up clinical decision support systems.
We use an agent-based model to analyze the effects of spatial heterogeneity and agents' mobility ... more We use an agent-based model to analyze the effects of spatial heterogeneity and agents' mobility on social-ecological outcomes. Our model is a stylized representation of a dynamic population of agents moving and harvesting a renewable resource. Cooperators (agents who harvest an amount close to the maximum sustainable yield) and selfish agents (those who harvest an amount greater than the sustainable yield) are simulated in the model. Three indicators of the outcomes of the system are analyzed: the number of settlements, the resource level, and the proportion of cooperators in the population. Our paper adds a more realistic approach to previous studies on the evolution of cooperation by considering a social-ecological system in which agents move in a landscape to harvest a renewable resource. Our results conclude that resource dynamics play an important role when studying levels of cooperation and resource use. Our simulations show that the agents' mobility significantly affects the outcomes of the system. This response is nonlinear and very sensible to the type of spatial distribution of the resource richness. In our simulations, better outcomes of long-term sustainability of the resource are obtained with moderate agent mobility and cooperation is enhanced in harsh environments with low resource level in which cooperative groups have natural boundaries fostered by agents' low mobility.
Urbanization is one of the main drivers threatening biodiversity. Together with the direct effect... more Urbanization is one of the main drivers threatening biodiversity. Together with the direct effects of exurban sprawl (e.g., habitat loss), the behavior of new residents may have important implications for species conservation. This manuscript addresses the effects of exurban sprawl on the collection and captivity of the endangered spur-thighed tortoise (Testudo graeca) in southeastern Spain. In June 2004, we undertook 362 structured interviews with exurban residents. Our results showed that most of the 12% of new residents who keeps tortoises in captivity have collected them from the wild (51%). Reintroductions and captive breeding were also frequent practices (24% and 26%, respectively). These practices, which are expected to increase in forthcoming years, might have important implications for the conservation of the species (local extinction, disease spread, or genetic mixing). Paradoxically, new residents collect tortoises to ''protect'' wild individuals from natural and anthropic threats. Therefore, even though many new residents are concerned about the spur-thighed tortoise, they do not practice sound conservation measures. This study highlights the importance of incorporating human dimensions for wildlife into planning for urban sprawl.
Context. Understanding how people view, think and talk about wildlife and the link between wildli... more Context. Understanding how people view, think and talk about wildlife and the link between wildlife and human behaviour are important for wildlife management to be effective. In this paper, we used the notion of social representations to understand people's behaviour towards wildlife. We qualitatively studied social representations relating to the keeping in captivity of the endangered tortoise Testudo graeca in south-east Spain.
The context in which many self-governed commons systems operate will likely be significantly alte... more The context in which many self-governed commons systems operate will likely be significantly altered as globalization processes play out over the next few decades. Such dramatic changes will induce some systems to fail and subsequently to be transformed, rather than merely adapt. Despite this possibility, research on globalization-induced transformations of social-ecological systems (SESs) is still underdeveloped. We seek to help fill this gap by exploring some patterns of transformation in SESs and the question of what factors help explain the persistence of cooperation in the use of common-pool resources through transformative change. Through the analysis of 89 forest commons in South Korea that experienced such transformations, we found that there are two broad types of transformation, cooperative and noncooperative. We also found that two system-level properties, transaction costs associated group size and network diversity, may affect the direction of transformation. SESs with smaller group sizes and higher network diversity may better organize cooperative transformations when the existing system becomes untenable.
Human behavior is an important factor in understanding the impact of exurban sprawl (i.e. low-den... more Human behavior is an important factor in understanding the impact of exurban sprawl (i.e. low-density rural home development) on native species. We studied the long-term effect of pet collection on populations of the threatened spur-thighed tortoise by residents of exurban areas in southeastern Spain. We built a system dynamic model using authors' own data and bibliographic data about tortoise population dynamics, the housing development dynamics, and the behavior of local residents toward this species. The model includes two submodels (spur-thighed population dynamics and households dynamics) interconnected through a tortoise collection submodel. Simulations showed that exurban intensity (i.e. size of a housing development) is essential in determining the intensity and speed of tortoise population decrease. Populations may become extinct due to collection in areas around medium to large housing developments (above 650 houses). Low housing development causes a considerable reduction of original population levels (more than 14%). Environmental education program by itself, with the aim of reducing the willingness of new residents to keep tortoises in captivity, does not seem very effective. The quality and the speed with which the educational program is initialized are key factors in determining the effectiveness of the educational program. The scenarios simulation results suggest that the integration of policies of strong development constraints and educational programs are the most effective way in reducing the impact of exurban development on tortoise populations.
Nota de Redacción; Por coherencia con el contenido de este articulo, todas las fotografías que lo... more Nota de Redacción; Por coherencia con el contenido de este articulo, todas las fotografías que lo ilustran corresponden a reintroducciones de fauna silvestre. Han sido selec cionadas por criterios de edición y diseño, pero en ningún caso su pu blicación conlleva una valoración implícita de la calidad o éxito del proyecto correspondiente.
Athletes who illicitly use drugs to enhance their athletic performance are at risk of being banne... more Athletes who illicitly use drugs to enhance their athletic performance are at risk of being banned from sports competitions. Consequently, some athletes may seek new doping methods that they expect to be capable of circumventing detection. With advances in gene transfer vector design and therapeutic gene transfer, and demonstrations of safety and therapeutic benefit in humans, there is an increased probability of the pursuit of gene doping by athletes. In anticipation of the potential for gene doping, assays have been established to directly detect complementary DNA of genes that are top candidates for use in doping, as well as vector control elements. The development of molecular assays that are capable of exposing gene doping in sports can serve as a deterrent and may also identify athletes who have illicitly used gene transfer for performance enhancement. PCR-based methods to detect foreign DNA with high reliability, sensitivity, and specificity include TaqMan real-time PCR, nested PCR, and internal threshold control PCR.
International Journal of the Commons, Sep 14, 2011
Abstract Globalization increases the vulnerability of traditional social-ecological systems (SES)... more Abstract Globalization increases the vulnerability of traditional social-ecological systems (SES) to the incursion of new resource appropriators, ie intruders. New external disturbances that increase the physical and socio-political accessibility of SES (eg construction of a new road) and weak points in institutional SES of valuable common-pool resources are some of the main factors that enhance the encroachment of intruders. The irrigation system of the northwest Murcia Region (Spain) is an example used in this article ...
Collecting tortoises for the pet trade is one of the factors threatening species of Testudo in th... more Collecting tortoises for the pet trade is one of the factors threatening species of Testudo in the Mediterranean area. The collection of Testudo graeca graeca for pets is described in southeast Spain, where the main European population of this subspecies coincides with an area where keeping tortoises in captivity is a long-established custom. This present paper, based on inquiries made to children, reveals that this practice continues to be a common activity, and estimates a captive population in the order of tens of thousand of tortoises. Tortoises are collected as a result of chance encounters with wild animals by local inhabitants, and without any commercial objectives. The captive breeding and the release of tortoises without any institutional control is also common. These activities could be an important threat for the species. Implications for conservation are discussed and a critical review of the conservation strategies developed in relation to this threat (trade control and re-introduction programmes) are presented. We suggest that environmental education programmes are necessary to reduce casual collection and to change the social perception of tortoises as pets.
This study was carried out in response to the growing interest on household biogas digesters in L... more This study was carried out in response to the growing interest on household biogas digesters in Latin America, particularly in rural Andean communities. The aim was to compare the fixed dome and plastic tubular digester in terms of biogas production, cost and environmental impact, using the life cycle assessment methodology. Design and operational parameters, construction materials and implementation costs were based on our previous research and literature results for plastic tubular and fixed dome digesters, respectively. According to this analysis, the main advantage of the plastic tubular digester was its ease of implementation and handling, and lower investment cost compared to the fixed dome digester, which appeared to be more environmentally friendly.
Currently, the best way to reduce the mortality of cancer is to detect it and treat it in the ear... more Currently, the best way to reduce the mortality of cancer is to detect it and treat it in the earliest stages. Automatic decision support systems are very helpful in this task but their performance is constrained by different factors and sometimes it is difficult to find a method ...
In this article we want to assess the feasibility of using genetic algorithms as classifiers that... more In this article we want to assess the feasibility of using genetic algorithms as classifiers that could be used in clinical decision support systems, for urological diseases diagnosis in our case. The use of artificial neural networks is more common in this field, and we have previously tested their use with the same purpose. At the end of the document we compare the obtained results using genetic algorithms and two different artificial neural networks implementations. The obtained accuracy rates show that genetic algorithms could be a useful tool to be used in the clinical decision support systems field.
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference, 2011
In this paper, we show the results of a study in which we try to test the feasibility of using ra... more In this paper, we show the results of a study in which we try to test the feasibility of using radial basis functions neural networks (RBFs for short) in clinical decision support systems. We have implemented two instances of RBFs in order to diagnose possible prostate cancer cases from a clinical database. To give an idea about how good the results are, we follow a two-fold approach. On the one hand they are independently evaluated in terms of accuracy, sensitivity and specificity and on the other hand they are compared with the performance over the same database of a classifier widely applied to the medical field problems, as it is multi-layer perceptron (MLP). The experimental results show that RBFs are a useful tool to build up clinical decision support systems.
We use an agent-based model to analyze the effects of spatial heterogeneity and agents' mobility ... more We use an agent-based model to analyze the effects of spatial heterogeneity and agents' mobility on social-ecological outcomes. Our model is a stylized representation of a dynamic population of agents moving and harvesting a renewable resource. Cooperators (agents who harvest an amount close to the maximum sustainable yield) and selfish agents (those who harvest an amount greater than the sustainable yield) are simulated in the model. Three indicators of the outcomes of the system are analyzed: the number of settlements, the resource level, and the proportion of cooperators in the population. Our paper adds a more realistic approach to previous studies on the evolution of cooperation by considering a social-ecological system in which agents move in a landscape to harvest a renewable resource. Our results conclude that resource dynamics play an important role when studying levels of cooperation and resource use. Our simulations show that the agents' mobility significantly affects the outcomes of the system. This response is nonlinear and very sensible to the type of spatial distribution of the resource richness. In our simulations, better outcomes of long-term sustainability of the resource are obtained with moderate agent mobility and cooperation is enhanced in harsh environments with low resource level in which cooperative groups have natural boundaries fostered by agents' low mobility.
Urbanization is one of the main drivers threatening biodiversity. Together with the direct effect... more Urbanization is one of the main drivers threatening biodiversity. Together with the direct effects of exurban sprawl (e.g., habitat loss), the behavior of new residents may have important implications for species conservation. This manuscript addresses the effects of exurban sprawl on the collection and captivity of the endangered spur-thighed tortoise (Testudo graeca) in southeastern Spain. In June 2004, we undertook 362 structured interviews with exurban residents. Our results showed that most of the 12% of new residents who keeps tortoises in captivity have collected them from the wild (51%). Reintroductions and captive breeding were also frequent practices (24% and 26%, respectively). These practices, which are expected to increase in forthcoming years, might have important implications for the conservation of the species (local extinction, disease spread, or genetic mixing). Paradoxically, new residents collect tortoises to ''protect'' wild individuals from natural and anthropic threats. Therefore, even though many new residents are concerned about the spur-thighed tortoise, they do not practice sound conservation measures. This study highlights the importance of incorporating human dimensions for wildlife into planning for urban sprawl.
Context. Understanding how people view, think and talk about wildlife and the link between wildli... more Context. Understanding how people view, think and talk about wildlife and the link between wildlife and human behaviour are important for wildlife management to be effective. In this paper, we used the notion of social representations to understand people's behaviour towards wildlife. We qualitatively studied social representations relating to the keeping in captivity of the endangered tortoise Testudo graeca in south-east Spain.
The context in which many self-governed commons systems operate will likely be significantly alte... more The context in which many self-governed commons systems operate will likely be significantly altered as globalization processes play out over the next few decades. Such dramatic changes will induce some systems to fail and subsequently to be transformed, rather than merely adapt. Despite this possibility, research on globalization-induced transformations of social-ecological systems (SESs) is still underdeveloped. We seek to help fill this gap by exploring some patterns of transformation in SESs and the question of what factors help explain the persistence of cooperation in the use of common-pool resources through transformative change. Through the analysis of 89 forest commons in South Korea that experienced such transformations, we found that there are two broad types of transformation, cooperative and noncooperative. We also found that two system-level properties, transaction costs associated group size and network diversity, may affect the direction of transformation. SESs with smaller group sizes and higher network diversity may better organize cooperative transformations when the existing system becomes untenable.
Human behavior is an important factor in understanding the impact of exurban sprawl (i.e. low-den... more Human behavior is an important factor in understanding the impact of exurban sprawl (i.e. low-density rural home development) on native species. We studied the long-term effect of pet collection on populations of the threatened spur-thighed tortoise by residents of exurban areas in southeastern Spain. We built a system dynamic model using authors' own data and bibliographic data about tortoise population dynamics, the housing development dynamics, and the behavior of local residents toward this species. The model includes two submodels (spur-thighed population dynamics and households dynamics) interconnected through a tortoise collection submodel. Simulations showed that exurban intensity (i.e. size of a housing development) is essential in determining the intensity and speed of tortoise population decrease. Populations may become extinct due to collection in areas around medium to large housing developments (above 650 houses). Low housing development causes a considerable reduction of original population levels (more than 14%). Environmental education program by itself, with the aim of reducing the willingness of new residents to keep tortoises in captivity, does not seem very effective. The quality and the speed with which the educational program is initialized are key factors in determining the effectiveness of the educational program. The scenarios simulation results suggest that the integration of policies of strong development constraints and educational programs are the most effective way in reducing the impact of exurban development on tortoise populations.
Nota de Redacción; Por coherencia con el contenido de este articulo, todas las fotografías que lo... more Nota de Redacción; Por coherencia con el contenido de este articulo, todas las fotografías que lo ilustran corresponden a reintroducciones de fauna silvestre. Han sido selec cionadas por criterios de edición y diseño, pero en ningún caso su pu blicación conlleva una valoración implícita de la calidad o éxito del proyecto correspondiente.
Athletes who illicitly use drugs to enhance their athletic performance are at risk of being banne... more Athletes who illicitly use drugs to enhance their athletic performance are at risk of being banned from sports competitions. Consequently, some athletes may seek new doping methods that they expect to be capable of circumventing detection. With advances in gene transfer vector design and therapeutic gene transfer, and demonstrations of safety and therapeutic benefit in humans, there is an increased probability of the pursuit of gene doping by athletes. In anticipation of the potential for gene doping, assays have been established to directly detect complementary DNA of genes that are top candidates for use in doping, as well as vector control elements. The development of molecular assays that are capable of exposing gene doping in sports can serve as a deterrent and may also identify athletes who have illicitly used gene transfer for performance enhancement. PCR-based methods to detect foreign DNA with high reliability, sensitivity, and specificity include TaqMan real-time PCR, nested PCR, and internal threshold control PCR.
International Journal of the Commons, Sep 14, 2011
Abstract Globalization increases the vulnerability of traditional social-ecological systems (SES)... more Abstract Globalization increases the vulnerability of traditional social-ecological systems (SES) to the incursion of new resource appropriators, ie intruders. New external disturbances that increase the physical and socio-political accessibility of SES (eg construction of a new road) and weak points in institutional SES of valuable common-pool resources are some of the main factors that enhance the encroachment of intruders. The irrigation system of the northwest Murcia Region (Spain) is an example used in this article ...
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