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The expectations and aspirations of a late-career professional womanAtkinson, Carol, Ford, Jackie M., Harding, Nancy H., Jones, F. 2015 June 1916 (has links)
Yes / This article presents a powerful account of one late-career woman's lived experiences. Little is known about women who continue professional careers into their 50s and beyond. Here insights are offered into her aspirations and expectations, as she reflects upon a career fragmented by gendered caring responsibilities and the implications of ageism and sexism together with health and body for her late-career phase. The narrative enhances understanding of the intersection of age and gender in a context where masculine career norms dominate. It also offers a reflection upon the implications of these themes for late-career women and their employing organizations more generally.
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Effect of population size on viable seed output, seed rand and natural regeneration pattern of a tropical conifer Widdringtonia whytei-Rendle in MalawiChanyenga, Tembo Faera 12 1900 (has links)
Thesis (PhD(For))--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Widdringtonia whytei is a tropical endemic, fire-adapted pioneer coniferous tree species
within natural fire-fragmented Afromontane forest patches in a confined area on Mulanje
Mountain in Malawi. Natural and anthropogenic fires within the surrounding fire-prone
landscape, insect attacks, and uncontrolled harvesting of mature trees for timber
threaten the survival of W. whytei. This study investigated the effects of population
fragmentation on the reproductive biology of W. whytei, through four specific studies:
effects of population size, tree size and crown position on viable seed output; seed rain
variation among population sizes; effects of temperature and light on viability and
germination of W. whytei seeds; and the influence of population size on natural
regeneration patterns.
The study was conducted during 2008 and 2009 on three sites using three W. whytei
population sizes: small (≤10 reproductively mature cone-bearing W. whytei trees),
medium (11-20 cone-bearing trees) and large (>20 cone-bearing trees). Data were
collected using field and laboratory experiments and a review of secondary information.
The effect of fragment size and crown position on viable seed output and seed rain
pattern was tested with a nested linear mixed model. The influence of stem diameter
(dbh) on viable seed output was tested using a separate data set. The variation in seed
rain was explored with a generalised linear model (GLM) with a negative binomial link
function. Variations in seed germination was analysed with a Weibull regression model.
The influence of fragment size on seedling regeneration was tested with a GLM (binary
logistic regression).
Viable seed output from W. whytei cones was very low (23%) and was not affected by
population size, tree diameter or crown position. W. whytei population size influenced
seed rain with large fragments having higher seed rain densities. Number of dispersed
seeds was generally very low and poorly dispersed. W. whytei cones are semiserotinous
and depends on moderate to severe fires for heavy seedfall and wider
dispersal. Such fires did not occur during the study period. Temperature is a critical
factor for seed germination. Seeds germinate between 15 and 25°C with the optimum at
~ 20°C either under light or dark conditions. Regeneration density followed the seed
rain pattern indicating that seed availability is a critical factor for regeneration. Regular
cool fires outside the forest patches and along the edges during the hot dry season, and
the thick litter layer and shady conditions inside forest patches, caused most of the
seedling mortality.
This study highlighted the difficulties W. whytei experiences with low output of viable
seed, limited seed dispersal and low seedling regeneration in and around forest
patches, i.e. factors important for conservation management of this species. It is
recommended that gaps with diameter equal to canopy height and occasional spot fires
would promote seed dispersal onto exposed mineral soil for rapid seedling
establishment and subsequent population growth. Such natural fire disturbance events
may show the true seed rain and seedling establishment patterns in this species. / AFRIKAANSE OPSOMMING: Widdringtonia whytei is ‘n tropiese endemiese, vuuraangepaste pionier naaldhoutagtige
boomsoort binne die natuurlike vuurgefragmenteerde Afromontane woudkolle binne ‘n
beperkte area op Mulanje berg in Malawi. Natuurlike en menslike vure binne die
omringende vuurgeneigde landskap, insekaanvalle, en onbeheerde kap van volwasse
bome vir hout bedreig die voortbestaan van W. whytei. Hierdie studie het die effek van
populasiefragmentasie op die voortplantingsbiologie van W. whytei ondersoek, deur vier
spesifieke studies: die effek van populasiegrootte, boomgrootte en kroonposisie op
produksie van lewenskragtige saad; saadreënvariasie tussen populasiegroottes; die
effek van temperatuur en lig op lewenskragtigheid en ontkieming van W. whytei saad;
en die invloed van populasiegrootte op natuurlike verjongingspatrone.
Die studie is gedurende 2008 en 2009 uitgevoer op drie groeiplekke met drie W. whytei
populasiegroottes: klein (≤10 keëldraende (volwasse) W. whytei bome), medium (11-20
keëldraende bome) en groot (>20 keëldraende bome). Data is versamel in veld- en
laboratorium eksperimente asook 'n oorsig van sekondêre inligting. Die invloed van
populasie fragmentgrootte en kroonposisie van bome op saadproduksie en die
saadreënpatroon is getoets met ‘n geneste liniêre gemengde model. Die invloed van
boomstamdeursnee op die produksie van kiemkragtige saad is met ‘n aparte datastel
getoets. Die variasie in saadreënpatroon is met 'n algemene liniêre model (GLM) met 'n
negatiewe binomiese skakelfunksie getoets. Variasies in ontkiemingspersentasie van
sade is met 'n Weibull regressiemodel ontleed. Die invloed van fragmentgrootte op
saailingverjonging is met 'n algemene linêre model (binêre logistiese regressie) getoets.
Produksie van lewenskragtige saad in W. whytei keëls was baie lag (23%) en was nie
deur populasiegrootte, boomstamdeursnee of kroonposisie beïnvloed nie. W. whytei
populasiegrootte het saadreën beïnvloed en groot fragmente het groter
saadreëndigthede gehad. Die aantal verspreide sade was in die algemeen baie laag en
swak versprei. W. whytei keëls is semi-saadhoudend (serotinous) en is afhanklik van
matige tot intense vure vir massiewe saadvrystelling en wyer saadverspreiding. Sulke
vure het nie gedurende die studieperiode voorgekom nie. Temperatuur is ‘n kritiese
factor vir saadontkieming. Sade ontkiem goed tussen 15 en 25°C met die optimum
rondom ~ 20°C onder beide lig en donker toestande. Fragmentgrootte het nie die
saailingverjonging in W. whytei beïnvloed nie. Verjongingsdigtheid het die
saadreënpatroon gevolg, wat daarop dui dat saadbeskikbaarheid ‘n kritiese factor is vir
saailingverjonging. Gereelde koel vure buite die woudkolle en langs die woudrand
gedurende die droë warm seisoen, en die dik lae blaarval (litter) en skadutoestande
binne ‘n woud, het meeste van die saailingmortaliteit veroorsaak.
Hierdie studie het die probleme beklemtoon wat W. whytei ondervind met die lae
produksie van kiemkragtige saad, saadverspreiding en saailingverjonging binne en
rondom die woudkolle, m.a.w. faktore wat belangrik is vir bewaringsbestuur van hierdie
boomsoort. Die aanbeveling word gemaak dat kroonopeninge met ‘n deursnee gelyk aan minstens die kroonhoogte, en sporadiese kolbrande binne die woudkolle kan
saadverspreiding op blootgestelde minerale grond vir vinnige saailingvestiging en
gevolglike populasiegroei bevorder. Sodanige vuurversteuringsgeleenthede mag die
werklike patrone in saadreën en saailingvestiging in hierdie species toon.
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Amphibian diversity conservation in a changing world : a view from MexicoOchoa Ochoa, Leticia Margarita January 2012 (has links)
Amphibians are the most abundant terrestrial vertebrates on Earth. They are crucial in maintaining the transfer of energy and matter from freshwater to terrestrial systems and are also indicators of ecosystem health. Mexico hosts great amphibian diversity with high levels of endemism. Nevertheless, the knowledge of amphibian ecology in the country is at an early stage. This thesis aspires to contribute to the knowledge of Mexican amphibian ecology and to the understanding of the processes underlying amphibian responses to environmental changes. To do so the thesis includes: 1) analyses from fine scales (at landscape level) based on data from two consecutive rainy seasons of fieldwork (nocturnal sampling), in two protected areas in southern Mexico, La Pera and Nahá; 2) at regional scales, analyses based on spatial databases of conservation instruments (i.e. environmental services, governmental, private, and community protected areas, etc.) generated specifically for Mexico; 3) to coarse scales (the whole country), analyses based on ecological niche modelling using the most complete database for Mexican amphibian records and climate layers developed purposely for the country. Thus, the thesis involves different time-scale processes, from ecological to biogeographical. In addition this thesis contains an analysis of the media representation of amphibian biodiversity threats and issues, specifically climate change, based on literature research. I was involved in the process of generating most of the databases used in this thesis. Whilst the main theme of this thesis is amphibian conservation, it also encompasses a wide range of specific subjects. Firstly, foundational knowledge about amphibian conservation is established in Chapter I. Also, the region, Chiapas in southern Mexico, where the fieldwork was carried out for two consecutive years (2009-2010) is described within a historical context and a glossary of terms is presented. In Chapter II, based on one year of fieldwork in two fragmented protected areas (PAs) of different management category, one state and one biosphere reserve, I examine how community structure is related to key features of the environment. The possible effects of governance issues in protected areas and their relationship with the drivers of amphibian metacommunities are also explored. A total of 144 transects were sampled from 33 patches in La Pera and 140 transects from 36 patches in Nahá. In each transect environmental variables were recorded. Partial Canonical Correspondence Analyses (partial CCA) indicated that the drivers of metacommunity patterns vary between the sampled landscapes. Habitat structure explained more of the community variation than either space or weather conditions: > 50% for La Pera and 30% Nahá; but the relationship to geographical space and local climate varied greatly. The differences in relationships among the environmental variables and between them and the amphibian metacommunities finds expression also in the pattern of human exploitation of these areas, which has latterly at least also found expression through differing governance. In Chapter III, the effects of environmental variation on metacommunities structure are explored. Metacommunity theory assumes that emergent properties can be determined that characterise a set of linked communities within a landscape. It follows that change in environmental conditions should generate changes in the metacommunity structure. In La Pera a total of 30 patches were sampled, with a total of 120 transects in 2009, and 133 transects in 2010. In Nahá 31 patches were sampled, with a total of 111 transects in 2009 and 122 transects in 2010. In the analyses of this chapter only transects sampled in both years are included. The total number of individuals increased greatly from 2009 to 2010, but the most abundant species between surveyed years varied slightly, in both areas. In La Pera metacommunity the structure changed from quasi-Clementsian to quasi-Gleasonian, while in Nahá it changed from Clementsian to Gleasonian. CCA show that the variance explained between years was similar. Re-arrangements in the metacommunity structures linked to environmental changes are observed. Results show that amphibian metacommunity structure can change with short environmental changes or disturbances, mainly weather variations from one year to another. This would suggest that metacommunity structures are a dynamic property in fluctuating systems. The aim of Chapter IV is to assess patterns of beta diversity for Mexican terrestrial vertebrates, and explore their relationships with environmental heterogeneity metrics at different spatial scales, identifying the most important surrogates at each spatial scale. The analyses in this chapter are based on the most complete database of Mexican terrestrial vertebrates, comprising distribution maps of 2513 species: 883 resident birds, 344 mammals, 364 amphibians and 811 reptiles. Higher β-diversity values are found along mountain ranges for amphibians, reptiles and mammals, whereas for birds high values are also found on the Mexican Plateau. Results demonstrate that the relationships between β-diversity and the environmental heterogeneity surrogates vary in form and strength across scale and between vertebrate groups. In Chapter V, I set out to characterize at fine scale, alpha and beta diversity patterns for Mexican amphibians and analyze how these patterns might change under a moderate climate-change scenario, and to highlight the overall consequences for amphibian diversity at the country level. The analyses are performed with a climatic envelope modelling approach using MaxEnt and a set of climatic layers developed specifically for Mexico. Models of future scenarios for Mexican amphibian alpha and beta diversity for 2020, 2050, 2080, show that high levels of species extinctions follow if low dispersal capability and high presence thresholds are used, but the overall geographic pattern of beta diversity remains stable. Zones of high beta diversity are associated with topographic formations, whilst the values of beta diversity initially increase, then decline over time under a moderate climate scenario. Extinctions (complete loss of range within country boundaries) are particularly intense during the period 2020–2050. The results imply that heterogeneous zones associated with mountain ranges will remain particularly important for amphibian diversity and thus such areas should be targeted for continued conservation prioritization in the face of climate change scenario. There is an inevitable degree of uncertainty associated with future climate projections and the possible ecological and biogeographical responses. Nevertheless, the climate change projections are typically translated in the media as certain. Chapter VI illustrates the interplay of these competing communication goals, through a review of the representations of the golden toad (Incilius [Bufo] periglenes) in print media and in peer-reviewed literature. The concept of “distanciation”, which means placing a distance between two connected issues (cause and effect), is introduced in this chapter, along with the potential issues that this process may generate in the implementation of conservation strategies. Distanciation is a perception created in the members of the audience of the media, but does not imply a total separation regarding an issue. For example, the audience is interested in the news about climate change effects, but they feel distant because the effects of climate change might be evident within a large time period (i.e. 2050); and although the causes are occurring now, the audience does not see the urgent need to act. Chapter VII represents the first attempt to analyze the status of conservation of some microendemic amphibians in Latin America when some social initiatives (e.g. private and community reserves) are included in the assessment. The efficiency of the existing set of governmental protected areas (PA), and the contribution of social initiatives for land protection of amphibians are evaluated. The chapter shows how the role of land conservation, through social initiatives, is fast becoming a crucial element for the survival of a substantial number of species not protected by state-designated PA. Given the current speed of land use change, we cannot expect to save all species from extinction, and so it must be decided, rather quickly, how to focus the limited resources available to prevent the greatest number of extinctions. In Chapter VIII, a simple conservation triage method is proposed. Using this triage method, the threat status for 145 micro-endemic Mexican amphibian species is evaluated, alongside potential threat abatement responses derived from existing policy instruments and social initiatives. Both indicators are combined to provide broad-scale conservation strategies that would best suit amphibian micro-endemic buffered areas (AMBAs) in Mexico. Results show that almost 25% of the species analysed urgently need field-base verification to confirm their persistence; for the rest, a conservation strategy is developed based on existing conservation instruments. Monitoring populations is essential in order to understand temporal patterns of community change and to better comprehend the underlying processes that shape and maintain biodiversity. These aspects, along with a general discussion focused mainly on the distanciation problem are addressed in Chapter IX.
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Identification des corrélats neuronaux associés à la clôture perceptive des objets : une étude en potentiels évoquésDésiré, Naddley 06 1900 (has links)
La capacité du système visuel humain à compléter une image partiellement dévoilée et à en dériver une forme globale à partir de ses fragments visibles incomplets est un phénomène qui suscite, jusqu’à nos jours, l’intérêt de nombreux scientifiques œuvrant dans différents milieux de recherche tels que l’informatique, l’ingénierie en intelligence artificielle, la perception et les neurosciences. Dans le cadre de la présente thèse, nous nous sommes intéressés spécifiquement sur les substrats neuronaux associés à ce phénomène de clôture perceptive.
La thèse actuelle a donc pour objectif général d’explorer le décours spatio-temporel des corrélats neuronaux associés à la clôture perceptive au cours d’une tâche d’identification d’objets. Dans un premier temps, le premier article visera à caractériser la signature électrophysiologique liée à la clôture perceptive chez des personnes à développement typique dans le but de déterminer si les processus de clôture perceptive reflèteraient l’interaction itérative entre les mécanismes de bas et de haut-niveau et si ceux-ci seraient sollicités à une étape précoce ou tardive lors du traitement visuel de l’information. Dans un deuxième temps, le second article a pour objectif d’explorer le décours spatio-temporel des mécanismes neuronaux sous-tendant la clôture perceptive dans le but de déterminer si les processus de clôture perceptive des personnes présentant un trouble autistique se caractérisent par une signature idiosyncrasique des changements d’amplitude des potentiels évoqués (PÉs). En d’autres termes, nous cherchons à déterminer si la clôture perceptive en autisme est atypique et nécessiterait davantage la contribution des mécanismes de bas-niveau et/ou de haut-niveau.
Les résultats du premier article indiquent que le phénomène de clôture perceptive est associé temporellement à l’occurrence de la composante de PÉs N80 et P160 tel que révélé par des différences significatives claires entre des objets et des versions méconnaissables brouillées. Nous proposons enfin que la clôture perceptive s’avère un processus de transition reflétant les interactions proactives entre les mécanismes neuronaux œuvrant à apparier l’input sensoriel fragmenté à une représentation d’objets en mémoire plausible.
Les résultats du second article révèlent des effets précoces de fragmentation et d’identification obtenus au niveau de composantes de potentiels évoqués N80 et P160 et ce, en toute absence d’effets au niveau des composantes tardives pour les individus avec autisme de haut niveau et avec syndrome d’Asperger. Pour ces deux groupes du trouble du spectre autistique, les données électrophysiologiques suggèrent qu’il n’y aurait pas de pré-activation graduelle de l’activité des régions corticales, entre autres frontales, aux moments précédant et menant vers l’identification d’objets fragmentés. Pour les participants autistes et avec syndrome d’Asperger, les analyses statistiques démontrent d’ailleurs une plus importante activation au niveau des régions postérieures alors que les individus à développement typique démontrent une activation plus élevée au niveau antérieur. Ces résultats pourraient suggérer que les personnes du spectre autistique se fient davantage aux processus perceptifs de bas-niveau pour parvenir à compléter les images d’objets fragmentés. Ainsi, lorsque confrontés aux images d’objets partiellement visibles pouvant sembler ambiguës, les individus avec autisme pourraient démontrer plus de difficultés à générer de multiples prédictions au sujet de l’identité d’un objet qu’ils perçoivent. Les implications théoriques et cliniques, les limites et perspectives futures de ces résultats sont discutées. / The human visual system has come to prevail over partially hidden boundaries and edges of objects in order to render a unified and holistic representation of the surrounding world. This phenomenon, also referred to as perceptual closure, was further investigated in the context of this current thesis. More precisely, this doctoral thesis aimed at examining the neural mechanisms underlying perceptual closure processes.
In order to achieve this goal, the first study to track the spatio-temporal dynamics of electrical brain activity during a pictorial object recognition task to determine whether closure processes are reflect an interplay between low-level and higher-level mechanisms and whether they are solicited during early or late stages of visual processing. We found that perceptual closure is temporally linked to the occurrence of the N80 and P160 which is the earliest negative ERP component sensitive to closure processes reported until now in previous similar studies. Results indicate that closure processes are implicated earlier during visual processing of fragmented object images. We propose here that perceptual closure is a transitional process that reflects the proactive interactions between neural mechanisms trying to match fragmented current sensory input with memory representations.
Furthermore, the second study sought to explore the time-course of neural correlates underpinning perceptual closure, during an object recognition task, to determine whether closure processes are associated with an abrupt or gradual change in ERP responses in adults with high functioning autism (HFA), Asperger’s Syndrome (AS) and in typically developing (TD) individuals. We found that, in individuals with HFA and AS, perceptual closure was associated with changes in early ERP (N80 and P160) responses for fragmentation and identification effects, while there were no significant modulations of later ERP responses. However, for TD individuals, perceptual closure was characterized by significant differences in early ERP responses (N80 and P160) between objects and non-objects as well as gradual modulations in late ERP responses for identification effects (450-550ms). Our results suggest that adults with autism rely mostly on low-level processes to achieve closure and do not illustrate the characteristic interplay between early and late ERP responses observed in typically developed individuals, thus revealing the atypicality of perceptual closure mechanisms in this population. We propose here that the interactive matching of incoming fragmented visual information with corresponding candidate object representations is atypical in individuals with autism.
Following these articles, we will discuss the theoretical and clinical implications of this work. Finally, we will also propose limitations within our studies and discuss new perspectives for future research.
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Identification et caractérisation des virus à ARN potentiellement pathogènes pour l'homme chez les populations de chauves-souris d'Afrique Centrale / Identification and characterization of RNA viruses potentially pathogenic to humans hosted by the populations of bats in Central AfricaMaganga, Gaël Darren 20 December 2012 (has links)
Le nombre de virus détectés chez les chauves-souris est en augmentation, la plupart étant des virus à ARN. L'identification chez différentes espèces de chauves-souris, de virus ayant été responsables d'épidémies voire de pandémies chez l'homme (coronavirus agent du SRAS, virus Nipah et Hendra, filovirus Ebola et Marburg) a fait prendre conscience du risque que peuvent présenter ces animaux pour la santé humaine, ainsi que des possibilités réelles d'émergence de nouvelles pathologies dans les années futures. Ce travail avait donc pour objectifs: (i) d'identifier et caractériser les virus circulant au sein des populations de chauves-souris d'Afrique Centrale et (ii) d'explorer et d'identifier des déterminants bioécologiques, qui pourraient expliquer la richesse virale observée chez certaines espèces de chauves-souris rencontrées en Afrique tropicale forestière. A partir d'un total de 3472 individus testés, représentant 16 espèces provenant du Gabon, de la République du Congo et de la République Centrafricaine, nous avons confirmé la présence du virus Marburg chez les roussettes d'Egypte (Rousettus aegyptiacus) au Gabon, et mis en évidence des séquences virales de paramyxovirus très proches de virus zoonotiques émergents (les virus Nipah et Hendra) et réémergents (virus des oreillons) chez des chauves-souris frugivores. Des séquences de nouveaux coronavirus, flavivirus et paramyxovirus ont été également identifiées. Par ailleurs, la fragmentation de l'aire de distribution et le type de gîte ont été identifiés comme des déterminants de la richesse virale chez 15 espèces de chauves-souris d'Afrique Centrale. Les chauves-souris en Afrique Centrale seraient donc des réservoirs de virus apparentés à des virus pathogènes pour l'homme. Ces animaux pourraient donc être à l'origine de l'émergence des encéphalites à hénipavirus en Afrique et de la réémergence de certaines maladies humaines comme les oreillons, la rougeole. Des recherches futures s'orienteront vers la poursuite de la caracterisation génétique des virus détectés chez les chauves-souris d'Afrique Centrale et la détermination du risque zoonotique associé à ces virus. Des études écologiques seront également réalisées pour identifier les facteurs de risque d'émeregence des virus de chauves-souris potentiellement pathogènes pour l'homme. / The number of viruses détected in bats is growing, the most common are RNA viruses. The identification in different bat species of viruses that cause major epidemics or pandemics in human such as SARS coronavirus, Nipah and Henda viruses, the filoviruses Ebola and Marburg has raised awareness of potential risk that these animals may present to human health, as well as real possibilities of development of new diseases in future years. This work had two objectives: (i) to identify and characterize the viruses circulating in populations of bats in Central Africa and (ii) to explore and identify bioecological factors that could explain the viral richness observed in some bats species seen in tropical Africa forest. From 3472 individuals tested accounting for 16 species from Gabon, Congo and the Central African Republic, we established the presence of Marburg virus in Egyptian fruit bats (Rousettus aegyptiacus) in Gabon and identified viral sequences of paramyxoviruses close related to emerging and re-emerging zoonotic paramyxoviruses (Nipah virus, Hendra viruses and mumps virus) in fruit bats. Sequences of novel coronaviruses, paramyxoviruses and flaviviruses have also beenidentified. Moreover, the fragmentation of the range and roost type have been identified as determinants of viral richness in 15 bats species of Central Africa. Bats in Central Africa thus would be reservoirs of viruses related to viruses pathogenic for humans. These animals would lead to the emergence of encephalitis Henipavirus in Africa and the reemergence of certain human diseases such as mumps, measles. Further research will be conducted to continue the genetic characterization of viruses detected from bats in Central Africa and to determine the zoonotic risk associated with these viruses. Ecological studies will also be performed to identify the risk factors for the emergence of bats viruses potentially pathogenic for humans.
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Variabilidade espacial nos estoques de carbono em paisagens fragmentadas da Mata Atlântica / Spatial variability in carbon stocks in the Atlantic Forest fragmented landscapesRomitelli, Isabella 04 July 2014 (has links)
O desmatamento e a fragmentação decorrentes da expansão das atividades humanas nas paisagens florestais tropicais promovem mudanças na estrutura da paisagem, em geral com perda de florestas antigas para a agricultura ou pastagem, parcialmente compensada regionalmente com a regeneração das florestas secundárias jovens. Tal processo gera paisagens heterogêneas, com florestas secundárias em diferentes estádios de sucessão e perturbação. O estoque de carbono nestas florestas pode, assim, variar muito e essa variação pode ocorrer em diferentes escalas espaciais. O presente estudo buscou entender como as diferentes condições locais e da paisagem contribuem para o estoque de carbono. O estudo foi realizado em florestas secundárias da Mata Atlântica, no Sistema Cantareira (região sudeste do Brasil). A biomassa acima do solo (BAS) foi estimada a partir de dados de inventário florestal e modelos alométricos de biomassa. A fim de testar como a biomassa de uma floresta tropical varia em paisagens antropizadas, foram construídos modelos lineares generalizados (GLM, distribuição Gaussiana) com quatro grupos de variáveis: idade da floresta; perturbações humanas; topografia (declividade e altitude); e estrutura da paisagem. Foram construídos modelos simples, compostos, com e sem interação, além do modelo nulo. O modelo mais plausível foi selecionado pelo critério de Akaike corrigido para pequenas amostras (AICc). Numa escala mais local, a variação da BAS em função da distância à borda foi analisada. A BAS variou amplamente entre os locais de estudo e isso foi parcialmente explicado pelas variáveis explanatórias, uma vez que todos os modelos e variáveis selecionadas foram melhores do que os modelos nulos. O resultado mais surpreendente foi o baixo estoque geral de carbono nas áreas de estudo (30,91 ± 11,00 Mg.ha-1). Os resultados sugerem que este padrão está principalmente relacionado com efeitos de borda e com a influência de fatores diretamente impulsionados pela ocupação humana (como, por exemplo, florestas mais perturbadas, paisagens com baixa cobertura florestal e ocorrência relativa alta de florestas mais jovens). Os resultados indicam ainda que nesta condição de alta perturbação os fatores abióticos, tais como a localização topográfica, podem ter uma importância menor do que seria de esperar por estudos anteriores. Os baixos estoques de carbono e alta variabilidade espacial observada indicam a necessidade de se incorporar estimativas de carbono em escalas espaciais mais finas em programas de mitigação climática e de manutenção de serviços ecossistêmicos em paisagens fragmentadas / Deforestation and fragmentation resulting from the expansion of human activities in tropical forest landscapes promote changes in landscape structure, usually with loss of mature forests for agriculture or pasture, partially offset regionally with the regeneration of young secondary forests. This process generates heterogeneous landscapes with secondary forests in different stages of succession and disturbance. The stock of carbon in these forests can thus vary greatly and this variation may occur at different spatial scales. This study aimed to understand how the different local and landscape conditions contribute to carbon stock. The study was performed in secondary Atlantic Forest fragments in Cantareira System (southeastern Brazil). The above-ground biomass (AGB) was estimated by forest inventory data and allometric biomass models. In order to test how the biomass of a tropical forest varies in disturbed landscapes, generalized linear models (GLM, Gaussian distribution) were constructed with four groups of variables: forest age; human disturbances; topography (terrain slope and elevation); and landscape structure. We constructed simple and compound, with and without interaction, models beyond to the null model. The most plausible model was selected by Akaike criterion corrected for small samples (AICc). On a more local scale, the variation of AGB according to the distance to the edge was analyzed. AGB varied widely among study sites and this was partly explained by the explanatory variables, since data suited better to all models and selected variables than the null model. The most surprising result was the low overall carbon stock in the study areas (30.91 ± 11.00 Mg.ha-1). The results suggest that this pattern is mainly related to edge effects and the influence of factors directly driven by human occupation (e.g. more disturbed forests, landscapes with low forest cover and high relative occurrence of younger forests). The results also indicate that this condition of high disturbance abiotic factors, such as the topographical location, may have less importance than would be expected from previous studies. Low carbon stocks and high spatial variability indicate the need to incorporate in carbon stock estimates a finer spatial scale for climate mitigation and maintenance of ecosystem services programs in fragmented landscapes
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Julgamento fracionado do mérito no processo civil brasileiro / Fragmented judgement of merit in Brazilian civil procedure law.Ambrizzi, Tiago Ravazzi 09 April 2015 (has links)
O estudo analisa, à luz do direito positivo em vigor no Brasil, a possibilidade de emissão de sentenças parciais dentro de um mesmo processo, de modo a solucionar por etapas o objeto litigioso. Procura-se demonstrar que não se trata de novidade absoluta, já convivendo o sistema brasileiro de longa data com situações de fracionamento da resposta judiciária, possibilidade que ficou amplificada com as sucessivas alterações por que passou o Código de Processo Civil Brasileiro. Examinam-se e refutam-se os afirmados obstáculos que impediriam ou contraindicariam o uso da técnica, com a demonstração de ser ela, em verdade, uma imposição do modelo processual constitucional brasileiro. Examinam-se aspectos técnicos ligados ao uso da técnica, verificando-se, principalmente: (i) em quais modalidades de cumulação de pedidos e de sujeitos ela tem cabimento; (ii) se também é possível falar na apreciação por etapas dos diferentes fundamentos da ação e da defesa; (iii) se a emissão de sentença parcial é ato discricionário ou vinculado do juiz; (iv) qual o momento adequado para que o juiz delibere acerca do custo financeiro do processo; (v) se é possível a formação gradual da coisa julgada dentro de um mesmo processo. Por fim, procura-se harmonizar o sistema de recursos ao uso da técnica, fazendo-se rápida menção aos sistemas jurídicos de outros países e ao Projeto do Novo Código de Processo Civil, que contempla o instituto aqui tratado na figura do Julgamento Antecipado Parcial do Mérito. / In the light of positive law in force in Brazil, this study analyses the possibility of partial judgements being given in relation to the same lawsuit, in order to settle litigation in stages. The study seeks to demonstrate that this is not an absolute novelty and that the Brazilian legal system has been accustomed for a long time to situations in which the judicial response is fragmented. This possibility has increased following the successive alterations undergone by the Brazilian Code of Civil Procedure. The obstacles alleged to prevent or counterindicate the use of this technique are examined and refuted, demonstrating that in truth the technique is an imposition of the Brazilian constitutional procedural model. An examination is made of the technical aspects related to the use of the technique, verifying in particular: (i) in which modes of joinder of claims and subjects it is admissible; (ii) if it is also possible for the different grounds for the suit and the defence to be examined in stages; (iii) if the giving of partial judgement is a discretionary or binding act of the judge; (iv) what is the appropriate moment for the judge to decide on the financial cost of the proceedings; (v) if it is possible for res judicata to be gradually formed within the same lawsuit. Finally an attempt is made to harmonize the appeal system with the use of the technique, referring rapidly to the legal systems of other countries and the Bill of Law for the New Code of Civil Procedure, which contemplates the institution dealt with here as Partial Summary Judgement of Merit.
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Regimes de visibilidade do corpo fragmentado e construção de sentido e interação na vídeoarte brasileiraRibeiro, Regilene Aparecida Sarzi 14 May 2012 (has links)
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Previous issue date: 2012-05-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The theme of this research is to build simulations of the fragmented body and
its role as an operator of the meaning and interaction of the individual in the
contemporary. The research objectives are: to analyze the role of the
organization figurative and plastic, the thematization of the body, the figuration
of the whole and the parts that link to different treatments of the subject and
intervene in the narrative and discursive interactions, study of social meaning
and visibility through the interactional relations arranged by the use of
expressive audiovisual system, the description of the procedures enunciative,
the apprehension of the individuals in interaction and processing a esthesic
sense of body self and other. The methodological basis of the research is based
on Discursive Semiotics of Algirdas Julien Greimas and his associates, in the
Semiotics of Plastic Jean-Marie Floch, in the field of social interactions
formalized by Eric Landowski Sociossemiótica and research in the semiotic
Brazilian Ana Claudia de Oliveira on the expression sensitive to global
enunciation of concreteness. The research corpus consists of four Brazilian
vídeoartes produced between the years 1975 and 2002. The actors of
utterances installed in the works prepared for analysis are artists belonging to
the first and current generation of Brazilian vídeo, as Leticia Parente, a pioneer
in the record of performing actions in the 1970s, and Nina Galanternick, Danillo
Barata and Lia Chaia, recognized for experimentation and research of vídeo
language. The vídeos have analyzed points in common, like the fact that the
body of the creator as the enunciator and surfactant statement and closeness
between some semantic categories, but differ in aesthetic treatment, plastic and
audiovisual syncretism. Research shows the fragmented body as an operator in
the sense vídeoartes and vídeo as a semiotic fact that it makes in the act, which
gives you the power to capture in close proximity to the body effect and its
enunciation of significant seizures of meaning. Of semiotic analysis comes to
the operationalization of aesthesia, procedures and metonymic description of
the effects of meaning generated in the interaction between the discursive body
language, gestures and kinetic and audiovisual language. The study contributes
to the area of communication, in that it presents original research, detailed and
elaborate procedure of mediation between the metonymic, the part for the
whole, interactive media and practices that expand the topic and offer referrals
relevant to future studies on the convergence between art and media, art and
communication / O tema desta pesquisa é a construção de simulacros do corpo fragmentado e sua
atuação como um operador do sentido e interação do sujeito no contemporâneo. Os
objetivos da pesquisa são: análise do papel da organização figurativa e plástica, da
tematização do corpo, da figuratividade do todo e das partes que apontam para
distintos tratamentos do sujeito e intervêm nas interações narrativas e
discursivas; estudo dos regimes de sentido e visibilidade por meio das relações
interacionais dispostas pelo uso do sistema expressivo audiovisual, da descrição dos
procedimentos enunciativos, da apreensão dos sujeitos em interação e do
processamento estésico do sentido do corpo do si mesmo e do outro. A base
metodológica da pesquisa é pautada na Semiótica Discursiva de Algirdas Julien
Greimas e seus colaboradores; na Semiótica Plástica de Jean-Marie Floch; no
campo das interações sociais formalizadas por Eric Landowski na Sociossemiótica e
nas pesquisas da semioticista brasileira Ana Claudia de Oliveira sobre a expressão
sensível como concretude da enunciação global. O corpus da pesquisa é constituído
por quatro vídeoartes brasileiras, produzidas entre os anos de 1975 e 2002. Os
atores das enunciações instalados nas obras recortadas para análise são artistas
pertencentes à primeira e à atual geração do vídeo brasileiro, como Letícia Parente,
pioneira no registro de ações performáticas na década de 1970, e Nina Galanternick,
Danillo Barata e Lia Chaia, reconhecidos pela experimentação e investigação da
linguagem vídeográfica. Os vídeos analisados possuem pontos em comum, como o
fato de ter o corpo do criador como enunciador e actante do enunciado e a
proximidade entre algumas categorias semânticas, mas se distinguem no tratamento
estético, plástico e sincrético do audiovisual. A investigação mostra o corpo
fragmentado como um operador de sentido nas vídeoartes e o vídeo como um fato
semiótico que se perfaz em ato, o que lhe dá competência para captar em
proximidade íntima o fazer sentido corpóreo e sua enunciação de apreensões
significantes da significação. Da análise semiótica provém à operacionalização da
estesia, dos procedimentos metonímicos e a descrição dos efeitos de sentido
gerados na interação discursiva entre as linguagens corporais, gestual e cinética e a
linguagem audiovisual. O estudo contribui para a área de Comunicação, na medida
em que apresenta uma investigação original, minuciosa e elaborada das mediações
entre o procedimento metonímico, a parte pelo todo, e as práticas interativas
midiáticas, que ampliam o tema e oferecem encaminhamentos relevantes para
estudos futuros sobre a convergência entre a arte e a mídia, a arte e a comunicação
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Connaitre les origines des paysages de la ville et de l’urbain, pour en débattre et agir : expérimentations pratiquées sur la Métropole du Grand Nancy / Know the origins of the landscapes of the city and the urban, to discuss it and act : experimentations on the Metropolis of Grand NancySimon, Jean-Marie 14 December 2018 (has links)
La Convention européenne du paysage et la problématique des Paysages Urbains Historiques proposée par l’Unesco, confirment l’importance d’une bonne connaissance des paysages pour une gestion du cadre bâti répondant aux besoins actuels. Mais, en France, les atlas du paysage, éléments essentiels de la politique paysagère s’attachent peu aux milieux urbains, apparemment pour des motifs méthodologiques. L’objectif est de réfléchir aux méthodes qui peuvent améliorer cette connaissance La première partie fait l’état de l’art du sujet, rappelle le rôle des paysages dans le bien-être quotidien individuel et collectif, inventorie les intervenants et les doctrines et établit un bilan des démarches actuelles. Une deuxième partie retrace les méthodes de la discipline géographique pour aborder les paysages de la ville et ses échanges avec d’autres disciplines : l’urbanisme, le paysage, l’architecture. La troisième partie, est une expérimentation qui s’appuie sur un atlas des paysages celui de la Meurthe-et-Moselle, et approfondit le territoire de la Métropole du Grand Nancy. La méthode retenue, issue de la pratique des transects, est accompagnée d’analyses paysagères ponctuelles relevant de la méthode des volets paysagers prévus par la loi Paysage de 1993. Une dizaine de secteurs est examinée : centre, entrée de ville, lotissement, grand ensemble zones industrielles. Cette approche permet de formuler quelques propositions méthodologiques qui clôturent l’expérimentation. / The European convention of the landscape and the problem of the Historic Urban landscapes proposed by UNESCO, confirm the importance of a good knowledge of the landscapes for a management of the built frame answering the current needs. But, in France, atlas of the landscape, essential elements of the landscaped politics, don’t take into consideration the urban landscapes, apparently for methodological motives. The objective is to think about the methods which can improve this Knowledge.The first part makes the state of the art of the subject, calls back the role of the landscapes in the individual and collective daily well-being, lists the speaker and the doctrines and establishes a balance sheet of the current steps. A second part redraws the methods of the geographical discipline to approach the landscape of the city and its exchanges with other disciplines: the town planning, the landscape, the architecture. The third part is an experiment which leans on an atlas of the landscapes of Meurthe-et-Moselle and deepens the territory of the Metropolis of Grand Nancy. The reserved method, stemming from the practice of transect, is accompanied by limited landscaped analyses coming from the method of the statutory landscaped based on the Landscape Law of 1993. About ten sectors are examined: center, city entrance, lot, large set industrial parks. This approach allows to formulate some methodological proposals which enclose the experiment.
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Variabilidade espacial nos estoques de carbono em paisagens fragmentadas da Mata Atlântica / Spatial variability in carbon stocks in the Atlantic Forest fragmented landscapesIsabella Romitelli 04 July 2014 (has links)
O desmatamento e a fragmentação decorrentes da expansão das atividades humanas nas paisagens florestais tropicais promovem mudanças na estrutura da paisagem, em geral com perda de florestas antigas para a agricultura ou pastagem, parcialmente compensada regionalmente com a regeneração das florestas secundárias jovens. Tal processo gera paisagens heterogêneas, com florestas secundárias em diferentes estádios de sucessão e perturbação. O estoque de carbono nestas florestas pode, assim, variar muito e essa variação pode ocorrer em diferentes escalas espaciais. O presente estudo buscou entender como as diferentes condições locais e da paisagem contribuem para o estoque de carbono. O estudo foi realizado em florestas secundárias da Mata Atlântica, no Sistema Cantareira (região sudeste do Brasil). A biomassa acima do solo (BAS) foi estimada a partir de dados de inventário florestal e modelos alométricos de biomassa. A fim de testar como a biomassa de uma floresta tropical varia em paisagens antropizadas, foram construídos modelos lineares generalizados (GLM, distribuição Gaussiana) com quatro grupos de variáveis: idade da floresta; perturbações humanas; topografia (declividade e altitude); e estrutura da paisagem. Foram construídos modelos simples, compostos, com e sem interação, além do modelo nulo. O modelo mais plausível foi selecionado pelo critério de Akaike corrigido para pequenas amostras (AICc). Numa escala mais local, a variação da BAS em função da distância à borda foi analisada. A BAS variou amplamente entre os locais de estudo e isso foi parcialmente explicado pelas variáveis explanatórias, uma vez que todos os modelos e variáveis selecionadas foram melhores do que os modelos nulos. O resultado mais surpreendente foi o baixo estoque geral de carbono nas áreas de estudo (30,91 ± 11,00 Mg.ha-1). Os resultados sugerem que este padrão está principalmente relacionado com efeitos de borda e com a influência de fatores diretamente impulsionados pela ocupação humana (como, por exemplo, florestas mais perturbadas, paisagens com baixa cobertura florestal e ocorrência relativa alta de florestas mais jovens). Os resultados indicam ainda que nesta condição de alta perturbação os fatores abióticos, tais como a localização topográfica, podem ter uma importância menor do que seria de esperar por estudos anteriores. Os baixos estoques de carbono e alta variabilidade espacial observada indicam a necessidade de se incorporar estimativas de carbono em escalas espaciais mais finas em programas de mitigação climática e de manutenção de serviços ecossistêmicos em paisagens fragmentadas / Deforestation and fragmentation resulting from the expansion of human activities in tropical forest landscapes promote changes in landscape structure, usually with loss of mature forests for agriculture or pasture, partially offset regionally with the regeneration of young secondary forests. This process generates heterogeneous landscapes with secondary forests in different stages of succession and disturbance. The stock of carbon in these forests can thus vary greatly and this variation may occur at different spatial scales. This study aimed to understand how the different local and landscape conditions contribute to carbon stock. The study was performed in secondary Atlantic Forest fragments in Cantareira System (southeastern Brazil). The above-ground biomass (AGB) was estimated by forest inventory data and allometric biomass models. In order to test how the biomass of a tropical forest varies in disturbed landscapes, generalized linear models (GLM, Gaussian distribution) were constructed with four groups of variables: forest age; human disturbances; topography (terrain slope and elevation); and landscape structure. We constructed simple and compound, with and without interaction, models beyond to the null model. The most plausible model was selected by Akaike criterion corrected for small samples (AICc). On a more local scale, the variation of AGB according to the distance to the edge was analyzed. AGB varied widely among study sites and this was partly explained by the explanatory variables, since data suited better to all models and selected variables than the null model. The most surprising result was the low overall carbon stock in the study areas (30.91 ± 11.00 Mg.ha-1). The results suggest that this pattern is mainly related to edge effects and the influence of factors directly driven by human occupation (e.g. more disturbed forests, landscapes with low forest cover and high relative occurrence of younger forests). The results also indicate that this condition of high disturbance abiotic factors, such as the topographical location, may have less importance than would be expected from previous studies. Low carbon stocks and high spatial variability indicate the need to incorporate in carbon stock estimates a finer spatial scale for climate mitigation and maintenance of ecosystem services programs in fragmented landscapes
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