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Role of the human chymase (CMA1) in the conversion of big-endothelin-1 to endothelin-1 (1-31) / Rôle de la chymase humaine (CMA1) dans la conversion de la big-endothéline-1 en endothéline-1 (1-31)Semaan, Walid January 2016 (has links)
Abstract : The chymase-dependant pathway responsible for converting Big ET-1 to ET-1 was established in
vitro. It has only been recently, in 2009, that our group demonstrated that the conversion of Big ET-1
to ET-1 (1-31) can occur in vivo in mice (Simard et al., 2009), knowing that ET-1 (1-31) is converted
to ET-1 via NEP in vivo (Fecteau et al., 2005). In addition, our laboratory demonstrated in 2013 that
mMCP-4, the murine analogue of human chymase, produces ET-1 (1-31) from the Big ET-1
precursor (Houde et al. 2013).
Thus far, in the literature, there are no specific characterizations of recombinant chymases (human or
murine). In fact, the group of Murakami published in 1995 a study characterizing the CMA1 (human
chymase) in a chymostatin-dependent fashion, using Angiotensin I as a substrate (Murakami et al.,
1995). However, chymostatin is a non-specific inhibitor of chymase. It has been shown that
chymostatin can inhibit elastase, an enzyme that can convert Angiotensin I to Angiotensin II (Becari
et al., 2005).
Based on these observations, the proposed hypothesis in the present study suggests that recombinant
as well as extracted CMA1 from LUVA (human mast cell line), in addition to soluble fractions of
human aortas, convert Big ET-1 into ET-1 (1-31 ) in a TY-51469 (a chymase-specific inhibitor)
sensitive manner.
In a second component, we studied the enzyme kinetics of CMA1 with regard to the Big ET-1 and
Ang I substrate. The affinity of CMA1 against Big ET-1 was greater compared to Ang I (KM Big
ET- 1: 12.55 μM and Ang I: 37.53 μM). However, CMA1 was more effective in cleaving Ang I
compared to Big ET-1 (Kcat / KM Big ET-1: 6.57 x 10-5 μM-1.s-1 and Ang I: 1.8 x 10-4 ΜM-1.s-
1).
In a third component involving in vivo experiments, the pressor effects of Big ET-1, ET-1 and Ang I
were tested in conscious mMCP-4 KO mice compared to wild-type mice. The increase in mean
arterial pressure after administration of Big ET-1 was greater in wild-type mice compared to mMCP-
4 KO mice. This effect was not observed after administration of ET-1 and / or Ang I. / Résumé : La voie de conversion de Big ET-1 en ET-1, chymase dépendante a été établie in vitro. Ce n'est que
récemment, en 2009 que notre groupe a démontré que la conversion de Big ET-1 en ET-1 (1-31) peut
avoir lieu in vivo chez la souris (Simard et al., 2009), sachant que ET-1 (1-31) est convertie en ET-1
via NEP in vivo (Fecteau et al., 2005). En plus, en 2013, notre laboratoire a démontré que la mMCP-
4, l'analogue murin de la chymase humaine, produit l'ET-1 (1-31) à partir du précurseur Big ET-1
(Houde et al., 2013). Jusqu'a présent, dans la littérature, on ne trouve pas de caractérisations
spécifiques de chymases (humaine ou murine) recombinantes. En fait, le groupe de Murakami, en
1995, a publié une étude caractérisant, d'une façon chymostatin dépendante, la CMA1 (chymase
humaine) en utilisant l'Angiotensine I comme substrat (Murakami et al., 1995). Cependant, le
chymostatin est un inhibiteur non-spécifique de la chymase. Il a été démontré que le chymostatin
peut inhiber l'élastase, une enzyme pouvant convertir l'Angiotensine I en Angiotensine II (Becari et
al., 2005). Basé sur ces observations, l'hypothèse formulée dans la présente étude est que la CMA1
recombinante ou extraite des cellules LUVA (lignée humaine de mastocytes) ou des fractions
solubles des aortes humaines convertit la Big ET-1 en ET-1 (1-31) d'une façon TY-51469 (un
inhibiteur spécifique de la chymase) sensible. Dans un deuxième volet, on a étudié la cinétique
enzymatique de CMA1 en vers le substrat Big ET-1 et Ang I. L’affinité de CMA1 contre la Big ET-1
était plus grande comparé à l’Ang I (KM Big ET-1 : 12.55 μM et Ang I : 37.53 μM). Cependant
CMA1 était plus efficace dans le clivage de l’Ang I comparé à la Big ET-1 (Kcat/KM Big ET-1 : 6.57
x 10-5
μM-1
.s-1
et Ang I : 1.8 x 10-4
μM-1
.s-1
). Dans un troisième volet impliquant des expériences in
vivo, l’effet presseur de la Big ET-1, l’ET-1 et l’Ang I a été testé chez des souris conscientes mMCP-
4 KO comparé à des souris de type sauvage. L’augmentation de la pression artérielle moyenne a été
plus importante chez les souris de type sauvage après l’administration de Big ET-1 que chez les
souris mMCP-4 KO. Cet effet n’a pas été observé après l’administration d’ET-1 et/ou d’Ang I ce qui
explique le rôle de la chymase dans l’effet de la conversion de Big ET-1 en ET-1 (1-31).
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Efeitos de barragem de hidrelétrica sobre áreas de uso e adequabilidade de habitat de onças-pintadas (Panthera onca) (Carnivora: Felidae) nas várzeas do Alto Rio Paraná, Mata AtlânticaSana, Denis Alessio January 2013 (has links)
Praticamente todos os ecossistemas naturais têm sido afetados pelas atividades humanas. A construção de usinas hidrelétricas produz grandes impactos ambientais causando problemas notáveis como a fragmentação e perdas de habitats. No Brasil aproximadamente 70% da matriz energética é formada por hidrelétricas e há previsão de expansão nos próximos anos. A degradação ambiental é apontada como a principal ameaça à conservação da biodiversidade e a maior causa do declínio das populações de espécies ameaçadas, especialmente de grandes mamíferos e, particularmente, de grandes carnívoros. Apesar da ampla distribuição no continente, as populações de onça-pintada (Panthera onca) têm sido reduzidas ou extintas pela pressão antrópica, tendo sua área de distribuição reduzida aproximadamente à metade. No Brasil é considerada uma espécie Vulnerável e está Criticamente Ameaçada de extinção na Mata Atlântica. Na Ecorregião Florestas do Alto Paraná está distribuída na forma de metapopulação, possivelmente em processo de isolamento de suas subpopulações. No Alto Rio Paraná a Usina Hidrelétrica de Porto Primavera (UHEPP) alagou em 1998 uma área de cerca de 2.250 km². A dissertação aborda este impacto ambiental e tem por objetivo avaliar como o enchimento do reservatório da UHEPP afetou a população de onças-pintadas na região, em relação à distribuição espacial e adequabilidade de habitat. Foram monitorados 11 indivíduos por radiotelemetria em dois períodos (1992 a 1995 e 1998 a 2002), investigando-se o tamanho de área de uso e movimentação. Com estes dados mais a cobertura de solo foram avaliadas adequabilidade ambiental e seleção de habitat. A distribuição espacial e a adequabilidade do habitat foram avaliadas em dois cenários, anterior e posterior ao enchimento, relacionando as mudanças ocorridas com o impacto na área sob o efeito direto do enchimento. Um terceiro cenário foi também avaliado, englobando toda a área de várzea remanescente no Alto Rio Paraná e incluindo as Unidades de Conservação (UCs), quanto à adequabilidade e seleção de habitat. Para este cenário foram utilizadas localizações de outros 10 indivíduos monitorados no Parque Estadual das Várzeas do Rio Ivinhema, Mato Grosso do Sul e no Parque Estadual Morro do Diabo, São Paulo, entre 1998 e 2005. Após o enchimento houve um aumento significativo nas dimensões das áreas de uso das onças-pintadas (fêmeas: anterior, 78 km² [n=8]; posterior, 197 km² [n=5]; macho [n=1]: anterior, 111 km²; posterior, 149 km²) bem como em seus deslocamentos máximos, pois passaram a ocupar áreas mais degradadas de fazendas, com poucos refúgios e presas naturais. Porém não foram observadas diferenças nos deslocamentos médios e sobreposição de áreas, assim como as áreas de uso não diferiram sazonalmente. A modelagem de habitat demonstrou que o enchimento atingiu principalmente as áreas mais favoráveis para a espécie suprimindo cerca de metade dessas. As onças selecionaram várzeas e florestas enquanto que a paisagem altamente modificada pelo homem foi evitada. Com as áreas mais degradadas ocupadas e o conflito com o homem, grande parte dos animais foram mortos em retaliação à predação de animais domésticos, levando praticamente a extinção local da espécie na área sob o efeito direto do enchimento. A área remanescente do Alto Rio Paraná comporta ainda cerca de 50 onças-pintadas adultas, sendo um terço em UCs. Portanto áreas adjacentes às UCs, na sua maioria com várzeas, devem ser preservadas e áreas florestais devem ser restauradas para a conservação da espécie em longo prazo na região. As informações geradas nesta dissertação podem auxiliar nas ações de conservação e manejo da onça-pintada no Alto Rio Paraná e mostra que a modelagem de habitat pode ser uma importante ferramenta para avaliação de impactos ambientais. / Virtually all natural ecosystems have been affected by human activities. The construction of hydroelectric power plants is the cause of major environmental impacts, such as habitat destruction and fragmentation. Brazil's energy matrix is mostly based on hydroelectricity, which comprises approximately 70% of all produced energy in the country, and the national government plans to expand it in the coming years. Habitat destruction is considered the main threat to biodiversity conservation and the major cause of the decline of endangered species, especially large mammals and large carnivores. Despite their wide distribution in the Americas, jaguar (Panthera onca) populations have been reduced or extinguished by human pressure, and the species current distribution represents half of its past distribution. In Brazil, the jaguar is considered a vulnerable species and it is critically endangered in the Atlantic Rain Forest. In the Upper Paraná Forest Ecoregion the species is distributed as a metapopulation, possibly in an isolation process of its subpopulations. In the Upper Paraná River (UPR), the reservoir filling of the Porto Primavera Hydroelectric plant (PPHE) began in 1998, and flooded an area of approximately 2250 km ². I evaluated the effects of the PPHE reservoir filling on the local jaguar population, its effects on the species spatial distribution and habitat suitability. I monitored a total of 11 jaguars using radio telemetry in two periods (1992-1995 and 1998-2002). I investigated jaguar home range size and movements, and evaluated habitat selection and suitability combing spatial and land cover data (Geographic Information System). These two metrics were measured before and after reservoir filling, linking the impact with changes in the species spatial patterns between these two phases. I evaluated three scenarios: the area affected directly by the PPHE filling, before and after, and all the remaining wetlands in the UPR, including protected areas. Jaguars’ home ranges increased significantly after reservoir filling (females: 78 km ² before [n = 8], 197 km ² after [n = 5]; male [n = 1]: 111 km ² before, 149 km ² after). Maximum movement of the four jaguars (3 females and 1 male) also increased from one phase to the other (10.75 km before; 25.05 km after). The increase in movement patterns results from jaguars using new and more degraded areas in farms, where there are few refuges and natural preys. Home ranges did not differ seasonally on the first period; neither did the mean movements and overlapping areas. The PPHE filling mainly affected jaguars by suppressing approximately half of their suitable area. Jaguars selected wetlands and forests and avoided landscapes heavily modified by Man. Most jaguars were killed in retaliation to cattle predation as they commenced to occupy the most degraded areas, nearly driving the population to extinction. The remaining area of the UPR still holds approximately 50 adult jaguars and one third of them are in protected areas. Therefore, the long-term species conservation depends on the preservation of the adjacent wetlands and on the restoration of forest patches. My results can subsidize jaguar conservation and management plans in the UPR and show that habitat suitability modeling can be a useful tool for assessing environmental impacts.
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Disturbances of autonomic functions in spinal cord injury: autonomic dysreflexia and thermoregulationKalincik, Tomas, Medical Sciences, Faculty of Medicine, UNSW January 2009 (has links)
Disorders of the autonomic nervous system constitute serious complications of spinal cord injury (SCI) and their treatment is usually highly prioritised by spinal patients. Among these, autonomic dysreflexia and impaired thermoregulation are potentially life threatening conditions and require effective management. Olfactory ensheathing cells (OECs), progenitor cells and polymeric scaffolds have been tested in animal models of SCI and some of them have been considered for clinical trials. However, evaluation of the effect of such interventions on autonomic functions has received only rudimentary attention and would require a more thorough experimental assessment before the methods are utilised in human patients. This thesis tested two potential therapeutic strategies for autonomic dysreflexia and examined disorders of thermoregulatory functions in a rat model of spinal cord transection. Magnitude and duration of autonomic dysreflexia were evaluated with radio telemetry in spinalised animals treated with (i) implants of OECs and olfactory neurosphere-derived cells seeded in poly(lactic co glycolic) porous scaffolds or with (ii) transplants of OECs alone. (iii) Effects of SCI and of OECs on the morphology of sympathetic preganglionic neurons (SPNs; which are involved in pathogenesis of autonomic dysreflexia) stained for NADPH diaphorase were examined. (iv) Doppler ultrasonography and infrared thermography were used to assess responses of tail blood flow and surface temperature to cold. Transplants of OECs alone, but not in combination with olfactory neurosphere-derived cells and polymeric scaffolds, resulted in significantly shortened episodes of autonomic dysreflexia. This may be attributed to the alterations to the morphology of SPNs adjacent to the lesion: a transient increase in the morphometric features of the SPNs was evoked by spinal cord transection and this was further altered by transplantation of OECs. The thesis also showed that local responses of tail blood flow and temperature to cold were not abolished by complete SCI suggesting that temperature homeostasis could still be maintained in response to cold. It is hypothesised that OECs facilitate improved recovery from autonomic dysreflexia through alteration of the morphology of SPNs. Furthermore, it is suggested that the role of the tail in heat conservation can be regulated by mechanisms that are independent of the descendent neural control from supraspinal centres.
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Habitat selection by moose (Alces alces) in southwestern Sweden / Älgars habitatval i sydvästra SverigeOlovsson, Anders January 2007 (has links)
<p>The moose (Alces alces) is very important both economically and ecologically, therefore all knowledge of moose is vital for future management of the moose population. Little is known about moose habitat selection in Sweden. In coastal southwestern Sweden growing human population and new infrastructure projects continuously threaten to fragment and isolate local moose populations. The habitat selection of 22 moose, 8 males and 14 females, in southwestern Sweden was studied from February 2002 until December 2005. The moose were captured and fitted with GPS-collars and positions were collected at 2-hour intervals. The number of moose positions totaled 71103 during the study period of 46 months. Data for individual animals were divided into four seasons: spring, summer, fall and winter based on climate and moose biology. A total of 125 moose seasonal home ranges were generated and habitat use within each of the generated home ranges was studied using Euclidean distance-based analysis. A reclassified digital landcover map was divided into the land use classes agriculture, clear-cut, coniferous forest, deciduous forest, mire and mountain. The results showed that there was a difference in habitat selection between males and females. Males were significantly closer to forest and clear-cuts compared to females. Both males and females selected clear-cuts and avoided agriculture within their home ranges.</p> / <p>Älgen är en viktig art, både ekonomiskt och ekologiskt, och all kunskap är viktig för att även i framtiden kunna sköta en sund älgstam. Trots flertalet studier finns det många frågetecken om älgens habitatval i Sverige. En ökad exploateringstakt och nya infrastrukturprojekt hotar att fragmentera och isolera populationer av älg. Habitatvalet hos 22 älgar, 8 tjurar och 14 kor, i sydvästra Sverige studerades mellan februari 2002 och december 2005. Älgarna sövdes och utrustades med GPS-sändare, deras positioner registrerades varannan timma och det totala antalet positioner under den 46 månader långa studietiden var 71103 stycken. Data från varje älg delades in i 4 säsonger; vår, sommar, höst och vinter, baserat på klimat och älgens biologi. Totalt genererades 125 hemområden baserade på säsong, och valet av habitat inom varje hemområde studerades med hjälp av Euclidean distance-based analysis. En omklassificerad digital marktäckedata användes som var indelad i 6 olika klasser; odlad mark, hygge, barrskog, lövskog, myrmark och berg i dagen. Resultaten visade att det var skillnad mellan könen i hur de väljer habitat. Tjurarna var signifikant närmare barrskog och hyggen än korna, men både tjurar och kor selekterade för hyggen och undvek odlad mark inom deras hemområden.</p>
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Habitat selection by moose (Alces alces) in southwestern Sweden / Älgars habitatval i sydvästra SverigeOlovsson, Anders January 2007 (has links)
The moose (Alces alces) is very important both economically and ecologically, therefore all knowledge of moose is vital for future management of the moose population. Little is known about moose habitat selection in Sweden. In coastal southwestern Sweden growing human population and new infrastructure projects continuously threaten to fragment and isolate local moose populations. The habitat selection of 22 moose, 8 males and 14 females, in southwestern Sweden was studied from February 2002 until December 2005. The moose were captured and fitted with GPS-collars and positions were collected at 2-hour intervals. The number of moose positions totaled 71103 during the study period of 46 months. Data for individual animals were divided into four seasons: spring, summer, fall and winter based on climate and moose biology. A total of 125 moose seasonal home ranges were generated and habitat use within each of the generated home ranges was studied using Euclidean distance-based analysis. A reclassified digital landcover map was divided into the land use classes agriculture, clear-cut, coniferous forest, deciduous forest, mire and mountain. The results showed that there was a difference in habitat selection between males and females. Males were significantly closer to forest and clear-cuts compared to females. Both males and females selected clear-cuts and avoided agriculture within their home ranges. / Älgen är en viktig art, både ekonomiskt och ekologiskt, och all kunskap är viktig för att även i framtiden kunna sköta en sund älgstam. Trots flertalet studier finns det många frågetecken om älgens habitatval i Sverige. En ökad exploateringstakt och nya infrastrukturprojekt hotar att fragmentera och isolera populationer av älg. Habitatvalet hos 22 älgar, 8 tjurar och 14 kor, i sydvästra Sverige studerades mellan februari 2002 och december 2005. Älgarna sövdes och utrustades med GPS-sändare, deras positioner registrerades varannan timma och det totala antalet positioner under den 46 månader långa studietiden var 71103 stycken. Data från varje älg delades in i 4 säsonger; vår, sommar, höst och vinter, baserat på klimat och älgens biologi. Totalt genererades 125 hemområden baserade på säsong, och valet av habitat inom varje hemområde studerades med hjälp av Euclidean distance-based analysis. En omklassificerad digital marktäckedata användes som var indelad i 6 olika klasser; odlad mark, hygge, barrskog, lövskog, myrmark och berg i dagen. Resultaten visade att det var skillnad mellan könen i hur de väljer habitat. Tjurarna var signifikant närmare barrskog och hyggen än korna, men både tjurar och kor selekterade för hyggen och undvek odlad mark inom deras hemområden.
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Nesting Range, Spatial Use, Habitat Selection and Sex Identification of the Greater Raodrunner (Geococcyx californianus)Montalvo, Andrea 14 March 2013 (has links)
I conducted this study to better understand the greater roadrunner’s (Geococcyx californianus) spatial use, nest site selection, and sexual morphometrics. Data were first collected from a roadrunner population in Fisher County, Texas. I trapped, measured, and removed feathers for sex confirmation through DNA PCR analysis. I then fit the roadrunners with a radio transmitter and released them at the capture site.
I captured a total of 10 birds (1 male and 9 females) and triangulated the location of each bird 2-4 times per week from February to August 2011 during the roadrunner nesting season. The data produced a mean minimum convex polygon nesting range of 43.01-ha, a 50% core utilization distributions of 11.88-ha, and an overlap index of 33.05 percent. Habitat selection ratios showed a preference for ridge as well as grassland habitat and avoidance of bare ground and flatland habitats.
The location data from west Texas was further analyzed to build a predictive logistic regression model to understand the significant site characteristics in roadrunner land use during the nesting season. It was determined that percent rock (-0.12, P = 0.0001) and percent litter (-0.05, P = 0.0052) were the best predictors in determining actual from random locations. Rock references open area for hunting, transportation as well as ridge habitat. Litter alludes to region below dense stands of shrubs and is used by roadrunners for evasion from threats and as shade for thermoregulation.
The measurements from the roadrunners in west Texas as well as museum specimens from across their natural range were combined to develop an easy, inexpensive, and field-relevant sex identification model. The strongest model consisted of bill depth (0.79, P< 0.0001) and bill tip to the back of the head (0.05, P = 0.1573) which were both found to be larger in males.
The final portion of this study concerned roadrunner nest site selection. Data were collected in Wilbarger County, Texas from May 2006 to October 2009. A predictive logistic regression model of nesting locations determined that mesquite nesting tree (-0.89, P = 0.0064), oval tree shape (1.58, P = 0.0118), mesquite density (-0.004, P = 0.0080), and topographic edge (1.37, P = 0.0027) were the best predictors in determining actual nest sites from random locations.
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Survival, reproduction, movement, and habitat use of female eastern wild turkeys (Meleagris gallopavo silvestris) in Manitoba’s Pembina ValleyKiss, Brian W. 07 January 2015 (has links)
Vital rates and movement patterns of eastern wild turkeys (Meleagris gallopavo silvestris) have never been studied at the northern extent of their North American range in Manitoba, Canada. Using radio telemetry during 2011 and 2012, this study collected estimates of female spring/summer survival, reproductive success, dispersal, home range size, and habitat use. Females had a 53% survival probability, 82% nesting frequency, 29% nesting success, 35% hen success, 11.3 eggs/clutch, 89% hatching success, and a natality rate of 2.3. Winter weather and relatively high predator numbers appear to have caused annual variation in survival and hen success. Spring dispersal distances and home ranges averaged 8.2 km and 554.4 ha, respectively. Home ranges were selected in relation to forests, cattle feedlots, and grasslands; while within home ranges, individuals selected areas close to grasslands, forests, and intermittent streams. These results can be used when modeling current populations, managing harvest, and structuring future releases.
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Disturbances of autonomic functions in spinal cord injury: autonomic dysreflexia and thermoregulationKalincik, Tomas, Medical Sciences, Faculty of Medicine, UNSW January 2009 (has links)
Disorders of the autonomic nervous system constitute serious complications of spinal cord injury (SCI) and their treatment is usually highly prioritised by spinal patients. Among these, autonomic dysreflexia and impaired thermoregulation are potentially life threatening conditions and require effective management. Olfactory ensheathing cells (OECs), progenitor cells and polymeric scaffolds have been tested in animal models of SCI and some of them have been considered for clinical trials. However, evaluation of the effect of such interventions on autonomic functions has received only rudimentary attention and would require a more thorough experimental assessment before the methods are utilised in human patients. This thesis tested two potential therapeutic strategies for autonomic dysreflexia and examined disorders of thermoregulatory functions in a rat model of spinal cord transection. Magnitude and duration of autonomic dysreflexia were evaluated with radio telemetry in spinalised animals treated with (i) implants of OECs and olfactory neurosphere-derived cells seeded in poly(lactic co glycolic) porous scaffolds or with (ii) transplants of OECs alone. (iii) Effects of SCI and of OECs on the morphology of sympathetic preganglionic neurons (SPNs; which are involved in pathogenesis of autonomic dysreflexia) stained for NADPH diaphorase were examined. (iv) Doppler ultrasonography and infrared thermography were used to assess responses of tail blood flow and surface temperature to cold. Transplants of OECs alone, but not in combination with olfactory neurosphere-derived cells and polymeric scaffolds, resulted in significantly shortened episodes of autonomic dysreflexia. This may be attributed to the alterations to the morphology of SPNs adjacent to the lesion: a transient increase in the morphometric features of the SPNs was evoked by spinal cord transection and this was further altered by transplantation of OECs. The thesis also showed that local responses of tail blood flow and temperature to cold were not abolished by complete SCI suggesting that temperature homeostasis could still be maintained in response to cold. It is hypothesised that OECs facilitate improved recovery from autonomic dysreflexia through alteration of the morphology of SPNs. Furthermore, it is suggested that the role of the tail in heat conservation can be regulated by mechanisms that are independent of the descendent neural control from supraspinal centres.
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Efeitos de barragem de hidrelétrica sobre áreas de uso e adequabilidade de habitat de onças-pintadas (Panthera onca) (Carnivora: Felidae) nas várzeas do Alto Rio Paraná, Mata AtlânticaSana, Denis Alessio January 2013 (has links)
Praticamente todos os ecossistemas naturais têm sido afetados pelas atividades humanas. A construção de usinas hidrelétricas produz grandes impactos ambientais causando problemas notáveis como a fragmentação e perdas de habitats. No Brasil aproximadamente 70% da matriz energética é formada por hidrelétricas e há previsão de expansão nos próximos anos. A degradação ambiental é apontada como a principal ameaça à conservação da biodiversidade e a maior causa do declínio das populações de espécies ameaçadas, especialmente de grandes mamíferos e, particularmente, de grandes carnívoros. Apesar da ampla distribuição no continente, as populações de onça-pintada (Panthera onca) têm sido reduzidas ou extintas pela pressão antrópica, tendo sua área de distribuição reduzida aproximadamente à metade. No Brasil é considerada uma espécie Vulnerável e está Criticamente Ameaçada de extinção na Mata Atlântica. Na Ecorregião Florestas do Alto Paraná está distribuída na forma de metapopulação, possivelmente em processo de isolamento de suas subpopulações. No Alto Rio Paraná a Usina Hidrelétrica de Porto Primavera (UHEPP) alagou em 1998 uma área de cerca de 2.250 km². A dissertação aborda este impacto ambiental e tem por objetivo avaliar como o enchimento do reservatório da UHEPP afetou a população de onças-pintadas na região, em relação à distribuição espacial e adequabilidade de habitat. Foram monitorados 11 indivíduos por radiotelemetria em dois períodos (1992 a 1995 e 1998 a 2002), investigando-se o tamanho de área de uso e movimentação. Com estes dados mais a cobertura de solo foram avaliadas adequabilidade ambiental e seleção de habitat. A distribuição espacial e a adequabilidade do habitat foram avaliadas em dois cenários, anterior e posterior ao enchimento, relacionando as mudanças ocorridas com o impacto na área sob o efeito direto do enchimento. Um terceiro cenário foi também avaliado, englobando toda a área de várzea remanescente no Alto Rio Paraná e incluindo as Unidades de Conservação (UCs), quanto à adequabilidade e seleção de habitat. Para este cenário foram utilizadas localizações de outros 10 indivíduos monitorados no Parque Estadual das Várzeas do Rio Ivinhema, Mato Grosso do Sul e no Parque Estadual Morro do Diabo, São Paulo, entre 1998 e 2005. Após o enchimento houve um aumento significativo nas dimensões das áreas de uso das onças-pintadas (fêmeas: anterior, 78 km² [n=8]; posterior, 197 km² [n=5]; macho [n=1]: anterior, 111 km²; posterior, 149 km²) bem como em seus deslocamentos máximos, pois passaram a ocupar áreas mais degradadas de fazendas, com poucos refúgios e presas naturais. Porém não foram observadas diferenças nos deslocamentos médios e sobreposição de áreas, assim como as áreas de uso não diferiram sazonalmente. A modelagem de habitat demonstrou que o enchimento atingiu principalmente as áreas mais favoráveis para a espécie suprimindo cerca de metade dessas. As onças selecionaram várzeas e florestas enquanto que a paisagem altamente modificada pelo homem foi evitada. Com as áreas mais degradadas ocupadas e o conflito com o homem, grande parte dos animais foram mortos em retaliação à predação de animais domésticos, levando praticamente a extinção local da espécie na área sob o efeito direto do enchimento. A área remanescente do Alto Rio Paraná comporta ainda cerca de 50 onças-pintadas adultas, sendo um terço em UCs. Portanto áreas adjacentes às UCs, na sua maioria com várzeas, devem ser preservadas e áreas florestais devem ser restauradas para a conservação da espécie em longo prazo na região. As informações geradas nesta dissertação podem auxiliar nas ações de conservação e manejo da onça-pintada no Alto Rio Paraná e mostra que a modelagem de habitat pode ser uma importante ferramenta para avaliação de impactos ambientais. / Virtually all natural ecosystems have been affected by human activities. The construction of hydroelectric power plants is the cause of major environmental impacts, such as habitat destruction and fragmentation. Brazil's energy matrix is mostly based on hydroelectricity, which comprises approximately 70% of all produced energy in the country, and the national government plans to expand it in the coming years. Habitat destruction is considered the main threat to biodiversity conservation and the major cause of the decline of endangered species, especially large mammals and large carnivores. Despite their wide distribution in the Americas, jaguar (Panthera onca) populations have been reduced or extinguished by human pressure, and the species current distribution represents half of its past distribution. In Brazil, the jaguar is considered a vulnerable species and it is critically endangered in the Atlantic Rain Forest. In the Upper Paraná Forest Ecoregion the species is distributed as a metapopulation, possibly in an isolation process of its subpopulations. In the Upper Paraná River (UPR), the reservoir filling of the Porto Primavera Hydroelectric plant (PPHE) began in 1998, and flooded an area of approximately 2250 km ². I evaluated the effects of the PPHE reservoir filling on the local jaguar population, its effects on the species spatial distribution and habitat suitability. I monitored a total of 11 jaguars using radio telemetry in two periods (1992-1995 and 1998-2002). I investigated jaguar home range size and movements, and evaluated habitat selection and suitability combing spatial and land cover data (Geographic Information System). These two metrics were measured before and after reservoir filling, linking the impact with changes in the species spatial patterns between these two phases. I evaluated three scenarios: the area affected directly by the PPHE filling, before and after, and all the remaining wetlands in the UPR, including protected areas. Jaguars’ home ranges increased significantly after reservoir filling (females: 78 km ² before [n = 8], 197 km ² after [n = 5]; male [n = 1]: 111 km ² before, 149 km ² after). Maximum movement of the four jaguars (3 females and 1 male) also increased from one phase to the other (10.75 km before; 25.05 km after). The increase in movement patterns results from jaguars using new and more degraded areas in farms, where there are few refuges and natural preys. Home ranges did not differ seasonally on the first period; neither did the mean movements and overlapping areas. The PPHE filling mainly affected jaguars by suppressing approximately half of their suitable area. Jaguars selected wetlands and forests and avoided landscapes heavily modified by Man. Most jaguars were killed in retaliation to cattle predation as they commenced to occupy the most degraded areas, nearly driving the population to extinction. The remaining area of the UPR still holds approximately 50 adult jaguars and one third of them are in protected areas. Therefore, the long-term species conservation depends on the preservation of the adjacent wetlands and on the restoration of forest patches. My results can subsidize jaguar conservation and management plans in the UPR and show that habitat suitability modeling can be a useful tool for assessing environmental impacts.
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Efeitos de barragem de hidrelétrica sobre áreas de uso e adequabilidade de habitat de onças-pintadas (Panthera onca) (Carnivora: Felidae) nas várzeas do Alto Rio Paraná, Mata AtlânticaSana, Denis Alessio January 2013 (has links)
Praticamente todos os ecossistemas naturais têm sido afetados pelas atividades humanas. A construção de usinas hidrelétricas produz grandes impactos ambientais causando problemas notáveis como a fragmentação e perdas de habitats. No Brasil aproximadamente 70% da matriz energética é formada por hidrelétricas e há previsão de expansão nos próximos anos. A degradação ambiental é apontada como a principal ameaça à conservação da biodiversidade e a maior causa do declínio das populações de espécies ameaçadas, especialmente de grandes mamíferos e, particularmente, de grandes carnívoros. Apesar da ampla distribuição no continente, as populações de onça-pintada (Panthera onca) têm sido reduzidas ou extintas pela pressão antrópica, tendo sua área de distribuição reduzida aproximadamente à metade. No Brasil é considerada uma espécie Vulnerável e está Criticamente Ameaçada de extinção na Mata Atlântica. Na Ecorregião Florestas do Alto Paraná está distribuída na forma de metapopulação, possivelmente em processo de isolamento de suas subpopulações. No Alto Rio Paraná a Usina Hidrelétrica de Porto Primavera (UHEPP) alagou em 1998 uma área de cerca de 2.250 km². A dissertação aborda este impacto ambiental e tem por objetivo avaliar como o enchimento do reservatório da UHEPP afetou a população de onças-pintadas na região, em relação à distribuição espacial e adequabilidade de habitat. Foram monitorados 11 indivíduos por radiotelemetria em dois períodos (1992 a 1995 e 1998 a 2002), investigando-se o tamanho de área de uso e movimentação. Com estes dados mais a cobertura de solo foram avaliadas adequabilidade ambiental e seleção de habitat. A distribuição espacial e a adequabilidade do habitat foram avaliadas em dois cenários, anterior e posterior ao enchimento, relacionando as mudanças ocorridas com o impacto na área sob o efeito direto do enchimento. Um terceiro cenário foi também avaliado, englobando toda a área de várzea remanescente no Alto Rio Paraná e incluindo as Unidades de Conservação (UCs), quanto à adequabilidade e seleção de habitat. Para este cenário foram utilizadas localizações de outros 10 indivíduos monitorados no Parque Estadual das Várzeas do Rio Ivinhema, Mato Grosso do Sul e no Parque Estadual Morro do Diabo, São Paulo, entre 1998 e 2005. Após o enchimento houve um aumento significativo nas dimensões das áreas de uso das onças-pintadas (fêmeas: anterior, 78 km² [n=8]; posterior, 197 km² [n=5]; macho [n=1]: anterior, 111 km²; posterior, 149 km²) bem como em seus deslocamentos máximos, pois passaram a ocupar áreas mais degradadas de fazendas, com poucos refúgios e presas naturais. Porém não foram observadas diferenças nos deslocamentos médios e sobreposição de áreas, assim como as áreas de uso não diferiram sazonalmente. A modelagem de habitat demonstrou que o enchimento atingiu principalmente as áreas mais favoráveis para a espécie suprimindo cerca de metade dessas. As onças selecionaram várzeas e florestas enquanto que a paisagem altamente modificada pelo homem foi evitada. Com as áreas mais degradadas ocupadas e o conflito com o homem, grande parte dos animais foram mortos em retaliação à predação de animais domésticos, levando praticamente a extinção local da espécie na área sob o efeito direto do enchimento. A área remanescente do Alto Rio Paraná comporta ainda cerca de 50 onças-pintadas adultas, sendo um terço em UCs. Portanto áreas adjacentes às UCs, na sua maioria com várzeas, devem ser preservadas e áreas florestais devem ser restauradas para a conservação da espécie em longo prazo na região. As informações geradas nesta dissertação podem auxiliar nas ações de conservação e manejo da onça-pintada no Alto Rio Paraná e mostra que a modelagem de habitat pode ser uma importante ferramenta para avaliação de impactos ambientais. / Virtually all natural ecosystems have been affected by human activities. The construction of hydroelectric power plants is the cause of major environmental impacts, such as habitat destruction and fragmentation. Brazil's energy matrix is mostly based on hydroelectricity, which comprises approximately 70% of all produced energy in the country, and the national government plans to expand it in the coming years. Habitat destruction is considered the main threat to biodiversity conservation and the major cause of the decline of endangered species, especially large mammals and large carnivores. Despite their wide distribution in the Americas, jaguar (Panthera onca) populations have been reduced or extinguished by human pressure, and the species current distribution represents half of its past distribution. In Brazil, the jaguar is considered a vulnerable species and it is critically endangered in the Atlantic Rain Forest. In the Upper Paraná Forest Ecoregion the species is distributed as a metapopulation, possibly in an isolation process of its subpopulations. In the Upper Paraná River (UPR), the reservoir filling of the Porto Primavera Hydroelectric plant (PPHE) began in 1998, and flooded an area of approximately 2250 km ². I evaluated the effects of the PPHE reservoir filling on the local jaguar population, its effects on the species spatial distribution and habitat suitability. I monitored a total of 11 jaguars using radio telemetry in two periods (1992-1995 and 1998-2002). I investigated jaguar home range size and movements, and evaluated habitat selection and suitability combing spatial and land cover data (Geographic Information System). These two metrics were measured before and after reservoir filling, linking the impact with changes in the species spatial patterns between these two phases. I evaluated three scenarios: the area affected directly by the PPHE filling, before and after, and all the remaining wetlands in the UPR, including protected areas. Jaguars’ home ranges increased significantly after reservoir filling (females: 78 km ² before [n = 8], 197 km ² after [n = 5]; male [n = 1]: 111 km ² before, 149 km ² after). Maximum movement of the four jaguars (3 females and 1 male) also increased from one phase to the other (10.75 km before; 25.05 km after). The increase in movement patterns results from jaguars using new and more degraded areas in farms, where there are few refuges and natural preys. Home ranges did not differ seasonally on the first period; neither did the mean movements and overlapping areas. The PPHE filling mainly affected jaguars by suppressing approximately half of their suitable area. Jaguars selected wetlands and forests and avoided landscapes heavily modified by Man. Most jaguars were killed in retaliation to cattle predation as they commenced to occupy the most degraded areas, nearly driving the population to extinction. The remaining area of the UPR still holds approximately 50 adult jaguars and one third of them are in protected areas. Therefore, the long-term species conservation depends on the preservation of the adjacent wetlands and on the restoration of forest patches. My results can subsidize jaguar conservation and management plans in the UPR and show that habitat suitability modeling can be a useful tool for assessing environmental impacts.
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