411 resultados para subdivision


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Sea-water intrusion is actively contaminating fresh groundwater reserves in the coastal aquifers of the Pioneer Valley,north-eastern Australia. A three-dimensional sea-water intrusion model has been developed using the MODHMS code to explore regional-scale processes and to aid assessment of management strategies for the system. A sea-water intrusion potential map, produced through analyses of the hydrochemistry, hydrology and hydrogeology, offsets model limitations by providing an alternative appraisal of susceptibility. Sea-water intrusion in the Pioneer Valley is not in equilibrium, and a potential exists for further landward shifts in the extent of saline groundwater. The model required consideration of tidal over-height (the additional hydraulic head at the coast produced by the action of tides), with over-height values in the range 0.5-0.9 m giving improved water-table predictions. The effect of the initial water-table condition dominated the sensitivity of the model to changes in the coastal hydraulic boundary condition. Several salination processes are probably occurring in the Pioneer Valley, rather than just simple landward sea-water advancement from modern sources of marine salts. The method of vertical discretisation (i.e. model-layer subdivision) was shown to introduce some errors in the prediction of watertable behaviour.

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The loss and fragmentation of forest habitats by human land use are recognised as important factors influencing the decline of forest-dependent fauna. Mammal species that are dependent upon forest habitats are particularly sensitive to habitat loss and fragmentation because they have highly specific habitat requirements, and in many cases have limited ability to move through and utilise the land use matrix. We addressed this problem using a case study of the koala (Phascolarctos cinereus) surveyed in a fragmented rural-urban landscape in southeast Queensland, Australia. We applied a logistic modelling and hierarchical partitioning analysis to determine the importance of forest area and its configuration relative to site (local) and patch-level habitat variables. After taking into account spatial auto-correlation and the year of survey, we found koala occurrence increased with the area of all forest habitats, habitat patch size and the proportion of primary Eucalyptus tree species; and decreased with mean nearest neighbour distance between forest patches, the density of forest patches, and the density of sealed roads. The difference between the effect of habitat area and configuration was not as strong as theory predicts, with the configuration of remnant forest becoming increasingly important as the area of forest habitat declines. We conclude that the area of forest, its configuration across the landscape, as well as the land use matrix, are important determinants of koala occurrence, and that habitat configuration should not be overlooked in the conservation of forest-dependent mammals, such as the koala. We highlight the implications of these findings for koala conservation. (c) 2006 Elsevier Ltd. All rights reserved.

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The Australian ghost bat is a large, opportunistic carnivorous species that has undergone a marked range contraction toward more mesic, tropical sites over the past century. Comparison of mitochondrial DNA (mtDNA) control region sequences and six nuclear microsatellite loci in 217 ghost bats from nine populations across subtropical and tropical Australia revealed strong population subdivision (mtDNA phi(ST) = 0.80; microsatellites URST = 0.337). Low-latitude (tropical) populations had higher heterozygosity and less marked phylogeographic structure and lower subdivision among sites within regions (within Northern Territory [NT] and within North Queensland [NQ]) than did populations at higher latitudes (subtropical sites; central Queensland [CQ]), although sampling of geographically proximal breeding sites is unavoidably restricted for the latter. Gene flow among populations within each of the northern regions appears to be male biased in that the difference in population subdivision for mtDNA and microsatellites (NT phi(ST) = 0.39, URST = 0.02; NQ phi(ST) = 0.60, URST = -0.03) is greater than expected from differences in the effective population size of haploid versus diploid loci. The high level of population subdivision across the range of the ghost bat contrasts with evidence for high gene flow in other chiropteran species and may be due to narrow physiological tolerances and consequent limited availability of roosts for ghost bats, particularly across the subtropical and relatively arid regions. This observation is consistent with the hypothesis that the contraction of the species' range is associated with late Holocene climate change. The extreme isolation among higher-latitude populations may predispose them to additional local extinctions if the processes responsible for the range contraction continue to operate.

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La Fibrosi Polmonare Idiopatica (IPF) è una malattia polmonare cronica, irreversibile la cui eziologia risulta essere ignota, caratterizzata da un processo fibrotico progressivo che inizia nel tratto respiratorio inferiore. Le persone affette da IPF presentano età media compresa tra 55 e 77 anni. L’incidenza annuale di IPF è stata recentemente stimata tra 14 e 42,7 casi per 100.000 persone e tale dato risulta essere in aumento. IPF fa parte delle malattie Polmonari Idiopatiche Interstiziali (IIP) che comprendono patologie con quadri istologici e clinici differenti. Le affezioni su cui si concentrerà questo studio sono: UIP (Usual Interstitial Pneumonia) caratterizzata da fibrosi interstiziale e dalla presenza di foci fibrotici connessi alla pleura e corrispondente al quadro anatomopatologico della maggior parte dei casi di IPF; NSIP (Non Specific Interstitial Pneumonia) simile alla UIP ma con maggiore uniformità temporale e spaziale delle manifestazioni; Sarcoidosi, malattia granulomatosa ad eziologia ignota. Attualmente la gravità della IPF, che implica una mortalità del 50% dei pazienti a 5 anni dall’esordio, e la scarsa efficacia farmacologica nel rallentarne la progressione vedono il trapianto polmonare come unica possibilità di sopravvivenza nelle forme più severe. Al momento non è chiaro il meccanismo patogenetico di insorgenza e progressione della IPF anche se sono stati individuati alcuni fattori scatenanti quali fumo di sigaretta, infezioni respiratorie e inquinanti atmosferici; tuttavia nessuno di tali elementi può da solo determinare un così esteso e progressivo rimodellamento del parenchima polmonare. Numerose sono le evidenze di come il substrato genetico, le alterazioni del rapporto morte/proliferazione cellulare e le citochine svolgano un ruolo nella genesi e nella progressione della malattia, ma non sono ancora chiari i fenomeni biologico-cellulari che la sostengono e, quindi, quali siano i punti di attacco per poter incidere terapeuticamente nel modificare l’evoluzione della IPF. Poiché il nostro laboratorio ha partecipato alla scoperta dell’esistenza di cellule staminali nel polmone umano normale, uno degli obiettivi finali di questo progetto si basa sull’ipotesi che un’alterazione del compartimento staminale svolga un ruolo cruciale nella eziopatogenesi di IPF. Per questo in precedenti esperienze abbiamo cercato di identificare nella IPF cellule che esprimessero antigeni associati a staminalità quali c-kit, CD34 e CD133. Questo lavoro di tesi si è proposto di condurre un’indagine morfometrica ed immunoistochimica su biopsie polmonari provenienti da 9 pazienti affetti da UIP, 3 da NSIP e 5 da Sarcoidosi al fine di valutare le alterazioni strutturali principali imputabili alle patologie. Preparati istologici di 8 polmoni di controllo sono stati usati come confronto. Come atteso, è stato osservato nelle tre patologie esaminate (UIP, NSIP e Sarcoidosi) un significativo incremento nella sostituzione del parenchima polmonare con tessuto fibrotico ed un ispessimento dei setti alveolari rispetto ai campioni di controllo. L’analisi dei diversi pattern di fibrosi presenti fa emergere come vi sia una netta differenza tra le patologie con una maggiore presenza di fibrosi di tipo riparativo e quindi altamente cellulata nei casi di UIP, e NSIP mentre nelle Sarcoidosi il pattern maggiormente rappresentato è risultato essere quello della fibrosi replacement o sostitutiva. La quantificazione delle strutture vascolari è stata effettuata tenendo separate le aree di polmone alveolare rispetto a quelle occupate da focolai sostitutivi di danno (componente fibrotica). Nei campioni patologici analizzati era presente un significativo riarrangiamento di capillari, arteriole e venule rispetto al polmone di controllo, fenomeno principalmente riscontrato nel parenchima fibrotico. Tali modifiche erano maggiormente presenti nei casi di NSIP da noi analizzati. Inoltre le arteriole subivano una diminuzione di calibro ed un aumento dello spessore in special modo nei polmoni ottenuti da pazienti affetti da Sarcoidosi. Rispetto ai controlli, nella UIP e nella Sarcoidosi i vasi linfatici risultavano inalterati nell’area alveolare mentre aumentavano nelle aree di estesa fibrosi; quadro differente si osservava nella NSIP dove le strutture linfatiche aumentavano in entrambe le componenti strutturali. Mediante indagini immunoistochimiche è stata documentata la presenza e distribuzione dei miofibroblasti, positivi per actina muscolare liscia e vimentina, che rappresentano un importante componente del danno tissutale nella IPF. La quantificazione di questo particolare fenotipo è attualmente in corso. Abbiamo inoltre analizzato tramite immunoistochimica la componente immunitaria presente nei campioni polmonari attraverso la documentazione dei linfociti T totali che esprimono CD3, andando poi a identificare la sottopopolazione di T citotossici esprimenti la glicoproteina CD8. La popolazione linfocitaria CD3pos risultava notevolmente aumentata nelle tre patologie analizzate soprattutto nei casi di UIP e Sarcoidosi sebbene l`analisi della loro distribuzione tra i vari distretti tissutali risultasse differente. Risultati simili si sono ottenuti per l`analisi dei linfociti CD8pos. La componente monocito-macrofagica è stata invece identificata tramite la glicoproteina CD68 che ha messo in evidenza una maggiore presenza di cellule positive nella Sarcoidosi e nella UIP rispetto ai casi di NSIP. I dati preliminari di questo studio indicano che il rimodellamento strutturale emo-linfatico e cellulare infiammatorio nella UIP si differenziano rispetto alle altre malattie interstiziali del polmone, avanzando l’ipotesi che il microambiente vascolare ed immunitario giochino un ruolo importante nella patogenesi della malattia

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In this thesis we present an approach to automated verification of floating point programs. Existing techniques for automated generation of correctness theorems are extended to produce proof obligations for accuracy guarantees and absence of floating point exceptions. A prototype automated real number theorem prover is presented, demonstrating a novel application of function interval arithmetic in the context of subdivision-based numerical theorem proving. The prototype is tested on correctness theorems for two simple yet nontrivial programs, proving exception freedom and tight accuracy guarantees automatically. The prover demonstrates a novel application of function interval arithmetic in the context of subdivision-based numerical theorem proving. The experiments show how function intervals can be used to combat the information loss problems that limit the applicability of traditional interval arithmetic in the context of hard real number theorem proving.

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The existence of different varieties of the acquired reading disorder termed "phonological dyslexia" is demonstrated in this thesis. The data are interpreted in terms of an information-processing model of normal reading which postulates autonomous routes for pronouncing lexical and non-lexical items and identifies a number of separable sub-processes within both lexical and non-lexical routes. A case study approach is used and case reports on ten patients who have particular difficulty in processing non-lexical stimuli following cerebral insult are presented, Chapters 1 and 2 describe the theoretical background to the investigation. Cognitive models of reading are examined in Chapter 1 and the theoretical status of the current taxonomy of the acquired dyslexias discussed in relation to the models. In Chapter 2 the symptoms associated with phonological dyslexia are discussed both in terms of the theoretical models and in terms of the cosistency with which they are reported to occur in clinical studies. Published cases of phonological dyslexia are reviewed. Chapter 3 describes the tests administered and the analysis of error responses. The majority of tests require reading aloud of single lexical or non-lexical items and investigate the effect of different variables on reading performance. Chapter 4 contains the case reports. The final chapter summarises the different patterns of reading behaviour observed. The theoretical model predicts the selective impairment of subsystems within the phonological route. The data provide evidence of such selective impairment. It is concluded that there are different varieties of phonological dyslexia corresponding to the different loci of impairment within the phonological route. It is also concluded that the data support the hypothesis that there are two lexical routes. A further subdivision of phonological dyslexia is made on the basis of selective impairment of the direct or lexical-semantic routes.

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The Lower Palaeozoic succession at Parys Mountain overlies a Precambrian basement (the Iona Series). This succession consists of Ordovician slates, overlain by, and in part interbedded with, Ordovician dacitic and rhyolitic volcanics, which in turn are unconformably overlain by Silurian slates. Both basement and Palaeozoic rocks have been deformed during Caledonian and Variscan orogenies. The resultant structure of Parys Mountain is interpreted as an east-north-easterly trending, single syncline overturned to the north. Many primary extrusive characters are retained by the volcanic rocks, despite the high degree of deformation. The lithologies and textures allow subdivision and interpretation of these rocks as dacite, lithic tuff, siliceous sinter, rhyolitic tuff, rhyolitic ignimbrite, rhyolitic tuff-lava, and rhyolitic lava. The results of 61 bulk chemical analyses are interpreted to show that the volcanism was of the orogenic calc-alkaline type from a continental margin/island arc environment. The magmas probably result from either partial melting of the crustal part of the oceanic lithosphere on a Benioff zone, or partial melting of the mantle, above a Benioff zone, under high load pressures and high water pressures. The mineral deposits are largely confined within the volcanic succession though some occur in the Ordovician and Silurian slates near to their contacts with the volcanics. The majority of the deposits form conformable lenses and tabular bodies, with subordinate deposits as veins and stockworks. The ore mineral assemblages are of chalcopyrite, galena, sphalerite, and pyrite. The general paragenetic sequence (73 sections) is pyrite--chalcopyrite--galena-sphalerite. The main mineralization episode is interpreted to be syngenetic, genetically related to the volcanism. The veins and stockworks probably result from Caledonian and Variscan remobilization of the primary mineralization. Trace element analyses (Cu, Zn, Pb, Ni, Co, Cd, Cr, Hg, Ba, Sr), on 350 specimens, detected anomalous concentrations of these elements around the mineralized zones, though some occur where no mineralization was found. The analyses also indicate a close relationship between the mineralization and the volcanic horizons, especially the siliceous sinter.

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The paper has been presented at the 12th International Conference on Applications of Computer Algebra, Varna, Bulgaria, June, 2006

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The matrix of this dissertation research permeates the design of complex environmental education. Its purpose is the realistic utopia of sustainability focused on the elucidation of a cultural model, a way of life that can guarantee the preservation of the living and non-living wight, to compose a world in which all coexist in harmony. To do so, thinking that model permeates the understanding that we are nature. This understanding can be evidenced both in Karl Marx in his book, the Economic and Philosophical Manuscripts says: "Nature is the essential body of the human being", and Joël de Rosnay, in his book The Symbiotic Man explains that we humans, "are the neurons of the earth." In this same perspective, Elisabet Sahtouris, in his book The Dance of the Earth, has pointed out how little is accurate to say that "there is life on Earth," because we are knowledgeable that our planet is a living organism, then there is the "life of the Earth ". Thus, we are part of this life, we are a part of the whole. With long experience in the environmental field, I seek the collective understanding that environmental education is a process belonging to all areas of knowledge, while margins for its subdivision occasion that begins the role of librarian I am, as a mediator of educational, cultural process, and disseminate information, is an environmental educator. Research conducted lead me to propose a revision of values and attitudes, from a certain reorganization of thought, an ecology of ideas and action, evidenced by readings of education and complexity, especially tuned to the writings of Edgar Morin. This thesis makes use of metaphor as a cognitive operator to emphasize the solar cycle, linking it to the development stages of this work. In summary, we have as a goal to emphasize the importance of the human condition, respect for nature and the principle of natural, cultural and social interdependence. In order for us to have a society that values relationships of solidarity with each other, respect and gratitude for living beings and Mother Earth. What leads me to converge, the reframing of the environment, understanding it as Integer Environment

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The thesis presents the results of research that addresses the performance of selective horizontal partitioning to promote Fire Safety in Buildings - FSB. Horizontal partitioning is a passive protection measure, settable in the early stages of the design process and controlled by the architect. However, there is a frequent reconfiguration of the rooms in academic buildings to adjust them for the space demand. Thus, large classrooms could turn into two or more smaller rooms, for example. Regardless when the subdivision occurs in the design phase or during the occupation of the building, the regulations just ensures the compartimentation of the room if all fireguard devices are present in the room. Knowing the fire's first minutes are the most important for life protection, we defend the hypothesis that a kind of partitioning ignored by regulatory standards is able to favoring the building vacancy and occupants rescue, for promote the room’s smoke exhaust. The performance of the selective horizontal partitioning due different blend of openings for smoke outlet was simulated on CFD software. The results indicate that selective horizontal partitioning is able to promote an upper smoke free layer and delay the indoor temperature growth.

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The thesis presents the results of research that addresses the performance of selective horizontal partitioning to promote Fire Safety in Buildings - FSB. Horizontal partitioning is a passive protection measure, settable in the early stages of the design process and controlled by the architect. However, there is a frequent reconfiguration of the rooms in academic buildings to adjust them for the space demand. Thus, large classrooms could turn into two or more smaller rooms, for example. Regardless when the subdivision occurs in the design phase or during the occupation of the building, the regulations just ensures the compartimentation of the room if all fireguard devices are present in the room. Knowing the fire's first minutes are the most important for life protection, we defend the hypothesis that a kind of partitioning ignored by regulatory standards is able to favoring the building vacancy and occupants rescue, for promote the room’s smoke exhaust. The performance of the selective horizontal partitioning due different blend of openings for smoke outlet was simulated on CFD software. The results indicate that selective horizontal partitioning is able to promote an upper smoke free layer and delay the indoor temperature growth.

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Many fish stocks are currently facing collapse or overexploitation as well as warming environments. During the 1950s and 1960s, haddock supported a substantial fishery in southern Newfoundland waters, specifically Northwest Atlantic Fisheries Organization (NAFO) Divisions 3LNO and Subdivision 3Ps, but abundance has been comparatively low over the last several decades and there has been no significant fishery in either 3LNO or 3Ps since the late-1950s. The decline in the fishery for haddock coincided with a decline in scientific research on haddock with the last significant research on haddock in Newfoundland waters conducted in the 1950s-1960s. Other haddock stocks have shown major life history changes since the 1980s, including decreased size-at-age and age/length at maturity. In contrast to this, Newfoundland haddock have not shown a significant change in growth or maturity through time. Based on analysis of habitat associations, haddock abundance is expected to increase with recent warming trends as the available optimum habitat for haddock will increase.

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The Nimish Subgroup igneous suite is a linear belt of volcanic and plutonic rocks in the Dyke Lake area of the southern Labrador Trough. The volcanics are interbedded with the sediments of the Wishart and Sokoman Formations of the Aphebian aged, Knob Lake Group. The sokoman Formation forms a time stratigraphic horizon that separates the lower Petitsikapau Lake Formation from the upper Astray Lake formation of the Nimish Subgroup. The occurrence of these volcanics within the Knob Lake Group is unique relative to Labrador Trough stratigraphy, as elsewhere the Knob Lake Group is a dominantly sedimentary succession and volcanics are restricted to the younger Doublet Group. Stratigraphic relationships between the Nimish Subgroup and the Sokoman formation indicate contemporaneous volcanic, clastic and chemical sedimentary activity. The internal stratigraphy of the Sokoman Formation exhibits a three-fold subdivision that is broadly correlatable with similar subdivisions in the Schefferville "main ore zone", 30 miles to the northwest. A detailed facies and paleogeographic model relating the volcanic activity to iron formation deposition in the Dyke Lake is presented. The rocks of the Dyke Lake area have been affected by lower greenschist facies metamorphism during the Hudsonian orogenic event, circa 1735 my. Geochemical evidence indicates that the igneous rocks of the Nimish Subgroup have been metasomatized with large degrees of mobility in Na₂O, K₂O, CaO, MgO, SiO₂, FeO and Fe₂O₃ suspected. The "immobile trace elements", Ti, Zr, Nb, Y and Ga imply that the Nimish lavas are a mildly alkaline suite that has an alkali basalt-trachyandesite-comendite differentiation scheme. The rare earth element, REE, geochemistry of the Nimish Subgroup is supportive of the alkaline nature of the volcanics and has been used to model the fractional crystallization petrogenesis involved in the two volcanic cycles. The geological, geochemical and geophysical evidence indicates that the Nimish Subgroup lavas are possibly a rift facies, alkaline suite related to the tensional tectonic regime that preceeded the extrusion of voluminous tholeiitic lavas of the Doublet Group.

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Late Neogene planktonic foraminifera have been examined at Site 310 in the Central North Pacific and their stratigraphic ranges and frequencies are presented here. Blow's (1969) zonation developed for tropical regions has been applied where applicable. Where tropical index taxa are rare or absent in this temperate region, Globorotalia crassaformis, and the evolutionary bioseries G. conoidea - G. conomiozea and G. puncticulata - G. inflata have been found useful for zonal subdivisions. A correlation between stratigraphic ranges and frequency distributions of these species at Site 310 in the Central North Pacific, and Site 284 in the Southwest Pacific indicates that these species are relatively consistent biostratigraphic markers in temperate regions of both the North and South Pacific Oceans. An informal zonation for temperate latitudes of the Southwest Pacific has been established by Kennett (1973) and a similar zonal subdivision can be made at Site 310. Paleoclimatic/paleoceanographic interpretations based on coiling ratios, percent abundance, and phenotypic variations of Neogloboquadrina pachyderma indicate four major cold events during early, middle, and late Pliocene, and early Pleistocene. Faunal correlations of these events with similar events elsewhere in the Northeast and Southwest Pacific which have been paleomagnetically dated indicate the following approximate ages for these cold events: 4.7 Ma, 3.0 Ma, 2.6-1.8 Ma, and 1.2 Ma. Faunal assemblages have been divided into three groups representing cool, intermediate, and warmer water assemblages. Cool water assemblages are dominated by ~60% N. pachyderma; intermediate temperature faunas are dominated by species of Globigerina and Globigerinita and contain between 20% and 30% N. pachyderma. Warmer water assemblages are dominated by species of Globorotalia and contain <10% N. pachyderma. Frequency oscillations within these groups, in addition to paleotemperature parameters evident in N. pachyderma, afford refined paleoclimatic/paleoceanographic interpretations.

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Late Neogene planktonic foraminiferal biostratigraphy of DSDP Site 296, Leg 31, reveals this site as an ideal reference section for correlation of Blow's low-latitude zonation with the mid-latitude zonation for temperate faunal assemblages developed in this paper and earlier for DSDP Site 310, Leg 31 (Keller). Abundance of temperate species of Globorotalia (G. inflata, G. puncticulata, G. crassaformis, G. conomiozea) permit correlation with the zonal subdivision developed at Site 310 based on these species. Evolutionary changes within the Globorotalia inflata group also appear to be consistent biostratigraphie markers in mid latitudes; a primitive variety of this species first appears at about 3.3-3.1 Ma, G. inflata praeinflata appears at about 2.6 Ma, and the modern form appears at about 2.2-2.1 Ma. Quantitative analyses of planktonic foraminifera at DSDP Site 296 reveal an inversely reciprocal frequency oscillation between species of Globorotalia and the Globigerina-Globigerinita group. Cool climatic periods are characterized by high frequencies in the Globigerina-Globigerinita group and low frequencies in the Globorotalia group, whereas warm intervals are marked by high frequencies in the Globorotalia group and low frequencies in the Globigerina-Globigerinita group. Five cool paleoclimatic events can be recognized between early Pliocene and late Pleistocene: 4.4 Ma, 3.2-3.1 Ma, 2.4-2.2 Ma, 1.2 Ma, and 0.7 Ma. These paleoclimatic/paleoceanographic events have also been recognized in planktonic foraminifera of the Central and Northeast Pacific DSDP Sites 310 and 173 and also correlate to cold events recognized in oxygen isotope measurements of DSDP Site 310 and in equatorial Pacific cores.