975 resultados para Geographical Distribution
Resumo:
The English Channel is located at the biogeographical boundary between the northern Boreal and southern Lusitanian biozones and therefore represents an important area to study the effects of global warming on marine organisms. While the consequences of climatic change in the western English Channel have been relatively well documented for fish, plankton and inter-tidal benthic communities, data highlighting the same effects on the distribution of sub-littoral benthic organisms does, to date, not exist. The present study resurveyed a subset of sites originally surveyed from 1958 to 1959 along the UK coast of the English Channel. The main aims of this resurvey were to describe the present status of benthic communities and to investigate potential temporal changes, in particular distributional changes in western stenothermal ‘cold’ water and southern Lusitanian ‘warm’ water species. The increase in water temperature observed since the historic survey was predicted to have caused a contraction in the distribution of cold water species and an extension in the distribution of warm water species. The temporal comparison did not show any clear broad-scale distributional changes in benthic communities consistent with these predictions. Nevertheless, 2 warm water species, the sting winkle Ocenebra erinacea and the introduced American slipper limpet Crepidula fornicata, did show range extensions and increased occurrence, possibly related to climatic warming. Similarly, warm water species previously not recorded by the historic survey were found. The absence of broad-scale temporal differences in sub-tidal communities in response to climatic warming has been reported for other areas and may indicate that these communities respond far more slowly to environmental changes compared to plankton, fish and inter-tidal organisms.
Resumo:
A locational duality in port-related distribution activities is emerging. In some regions, distribution activities have moved from ports to inland locations, driven in part by ‘push factors’ such as port congestion and scarcity of land for container handling activities, or by ‘pull factors’ such as the growth of intermodal corridors, the influence of inland terminals and the changing economic geography in the hinterland. In other regions, ports retain their traditional role as centres of distribution and warehousing activity. More recently, the focus on ‘port-centric logistics’ is indicative that some regions are refocusing on ports as potential locations for large distribution centres. The result has been a growing competition, but also complementarity, between ports and inland locations concerning the location of distribution activities, driven not only by market forces but also by institutional settings and the governance relations between the actors involved. This report provides an overview of regional differences across the world in order to develop a framework identifying for which type of distribution activities ports are suitable locations and which activities are best suited to the hinterland, taking into account geographical, economic and logistics settings. Empirical evidence is derived from a variety of regions in Europe, North America, South America, Southern Africa and Asia.
Resumo:
Khark & Kharko Islands are the last Northern point for fringing coral reefs in Iranian side of the Persian Gulf. These Coralline habitats are the Protected Area and Wildlife Refugees with the total area of 2400 ha which located in the territory of Bushehr Province. This research carried out during 2006-2007 with monthly sampling from 12 stations, which selected around Islands and inshore waters with maximum depth of 20 meter. Sampling was conducted using by Bongo-Net plankton sampler with 500μ of mesh size. Totally, 1808 specimen from 45 family fish larvae was identified in studied area, including: 21 coralline fish larva families and 24 shore fish larvae such as pelagic and demersal fishes which some of them known as indicator, sentinel or endemic species for coral reef ecosystems. The results was shown that coral reef diversity in coral reefs (Khark & Kharko Islands) is more than other habitats such as estuary and river mouth, creeks, mangrove forest sites, and off shore water of the Persian Gulf and Oman Sea Iranian side. Among Identified families, Clupeidae, Blenniidae, Sillaginidae, Atherinidae and Tripterygiidae; with more abundance were dominant families in studied area. The pick of fish larvae abundance family were estimated in spring. There were significant differences between seasonally abundance and sub areas, but there were not significant differences in diversity indexes between Khark and Kharko stations with coastal stations (p< 0.05). The mean abundance of fish larvae were estimated 18.7083 larvae under 10m² of sea surface, and the mean diversity indexes and evenness were estimated 0.7135 and 0.565342 consequently, that was showed the area is under ecological stress for fish larvae, and wasn’t stable. Therefore, from the ecological point of view, only some of the fish larvae groups as like Clupeidae were dominant. Thus, they were the main cause of the fish larvae abundance change in studied area. Due to geographical location of Khark and Kharko Islands and among the environmental parameters, Its seems that the condition of sea current is the main cause for present or absent and distribution patterns of fish larvae in area. Abundance of fish larvae in west of Islands was higher than eastern parts in the spring. But this condition will be reversed in eastern part of Island and several coastal stations, so that the Islands surrounding clock wise current to cause fish larvae distribution patterns.
Resumo:
The objective of this study was to estimate the spatial distribution of work accident risk in the informal work market in the urban zone of an industrialized city in southeast Brazil and to examine concomitant effects of age, gender, and type of occupation after controlling for spatial risk variation. The basic methodology adopted was that of a population-based case-control study with particular interest focused on the spatial location of work. Cases were all casual workers in the city suffering work accidents during a one-year period; controls were selected from the source population of casual laborers by systematic random sampling of urban homes. The spatial distribution of work accidents was estimated via a semiparametric generalized additive model with a nonparametric bidimensional spline of the geographical coordinates of cases and controls as the nonlinear spatial component, and including age, gender, and occupation as linear predictive variables in the parametric component. We analyzed 1,918 cases and 2,245 controls between 1/11/2003 and 31/10/2004 in Piracicaba, Brazil. Areas of significantly high and low accident risk were identified in relation to mean risk in the study region (p < 0.01). Work accident risk for informal workers varied significantly in the study area. Significant age, gender, and occupational group effects on accident risk were identified after correcting for this spatial variation. A good understanding of high-risk groups and high-risk regions underpins the formulation of hypotheses concerning accident causality and the development of effective public accident prevention policies.
Resumo:
European-wide conservation policies are based on the identification of priority habitats. However, research on conservation biogeography often relies on the results and projections of species distribution models to assess species' vulnerability to global change. We assess whether the distribution and structure of threatened communities can be predicted by the suitability of the environmental conditions for their indicator species. We present some preliminary results elucidating if using species distribution models of indicator species at a regional scale is a valid approach to predict these endangered communities. Dune plant assemblages, affected by severe conditions, are excellent models for studying possible interactions among their integrating species and the environment. We use data from an extensive survey of xerophytic inland sand dune scrub communities from Portugal, one of the most threatened habitat types of Europe. We identify indicator shrub species of different types of communities, model their geographical response to the environment, and evaluate whether the output of these niche models are able to predict the distribution of each type of community in a different region.
Resumo:
Aim Chorological relationships describe the patterns of distributional overlap among species. In addition to revealing biogeographical structure, the resulting clusters of species with similar geographical distributions can serve as natural units in conservation planning. Here, we assess the extent to which temporal, methodological and taxonomical differences in the source of species’ distribution data can affect the relationships that are found.
Resumo:
In Andalusia, southern Spain, each game estate applies its own rules and presents its results in annual hunting reports, which have been mandatory for Spanish game estates since 1989. We used the information about hunting yields, included in 32134 annual hunting reports produced during the period 1993/94 to 2001/02 by 6049 game estates, to determine the current distribution of hunting yields of big and small game species in Andalusia. Using generalised linear models and a geographic information system, we determined the most favourable municipalities to big and small game, respectively, and delimited potential areas to attain good hunting yields for big and small game at a 1-km2 resolution. Municipalities and areas favourable to big game are mainly located in the Sierra Morena and the westernmost fringe of the Betic Range, while those favourable to small game occupy the upper Guadalquivir River valley. There is a clear segregation between big and small game species according to the physiography and land uses of the territory. Big game species are typical of Mediterranean woodland areas, while the most emblematic small game species prefer agricultural areas. Our results provide a territorial ordination of hunting yields in southern Spain and have several potential applications in strategic planning for hunting activities and biodiversity conservation in Andalusia that can be extrapolated to other regions.
Resumo:
The aim of the project is the creation of a new model for the analysis of the political and social structures of the Northern Levant during the Iron Age, through the study of the production and circulation of ceramics in urban and rural centers. The project includes an innovative approach compared to a traditional contextual and analytical study of ceramic material. The geographical area under consideration represents an ideal context for understanding these dynamics, as a place of interaction between culturally different but constantly communicating areas (Eastern Mediterranean, Syria, Upper Mesopotamia). They corresponds to present-day southeastern Turkey and northern Syria, with the Mediterranean coast and the Euphrates River as limits to the west and east, respectively. The chronological interval taken into consideration by the study extends from the twelfth century BC. to the seventh century BC, corresponding to a phase of political fragmentation of the region into small-medium state entities and their subsequent conquest by the Neo-Assyrian empire starting from the end of the ninth century BC.
Resumo:
Although various abutment connections and materials have recently been introduced, insufficient data exist regarding the effect of stress distribution on their mechanical performance. The purpose of this study was to investigate the effect of different abutment materials and platform connections on stress distribution in single anterior implant-supported restorations with the finite element method. Nine experimental groups were modeled from the combination of 3 platform connections (external hexagon, internal hexagon, and Morse tapered) and 3 abutment materials (titanium, zirconia, and hybrid) as follows: external hexagon-titanium, external hexagon-zirconia, external hexagon-hybrid, internal hexagon-titanium, internal hexagon-zirconia, internal hexagon-hybrid, Morse tapered-titanium, Morse tapered-zirconia, and Morse tapered-hybrid. Finite element models consisted of a 4×13-mm implant, anatomic abutment, and lithium disilicate central incisor crown cemented over the abutment. The 49 N occlusal loading was applied in 6 steps to simulate the incisal guidance. Equivalent von Mises stress (σvM) was used for both the qualitative and quantitative evaluation of the implant and abutment in all the groups and the maximum (σmax) and minimum (σmin) principal stresses for the numerical comparison of the zirconia parts. The highest abutment σvM occurred in the Morse-tapered groups and the lowest in the external hexagon-hybrid, internal hexagon-titanium, and internal hexagon-hybrid groups. The σmax and σmin values were lower in the hybrid groups than in the zirconia groups. The stress distribution concentrated in the abutment-implant interface in all the groups, regardless of the platform connection or abutment material. The platform connection influenced the stress on abutments more than the abutment material. The stress values for implants were similar among different platform connections, but greater stress concentrations were observed in internal connections.
Resumo:
Reasons for the iniquities of caries, globally recognized, may be related to how Cariology has been taught in dental schools. In Brazil, the most important universities, when considering healthcare teaching, are the public ones. The objective of this study was to identify the insertion of the contents of Cariology in the course flowcharts of public dental schools in the country. The survey was conducted in 2013 seeking to identify the realities of different geographical regions, aimed to the census of public dental schools. It was performed a documentary analysis of the menus of disciplines, identifying the following issues: number of dental schools that include content related to Cariology in their curricula; average total workload undergraduate courses and disciplines that contemplate the theme; distribution of disciplines in professional training cycles (basic, clinical and public health); existence of discipline and/or a specific department; verification of bibliographic indication directly related to Cariology. The response rate was 93.6%. All dental schools recommended specific books, and none of them had a Department of Cariology. All dental schools in the country contemplated content related to Cariology in their disciplines, distributed in specific disciplines (except for the Northern region) and disciplines in the three cycles of learning (basic, clinical and public health), with larger workload in the clinical cycle. Although public dental schools in Brazil demonstrated commitment to contemplating the content related to Cariology in their disciplines, the emphasis on the clinical cycle may not be promoting the integrated formation of students, which could be contributing to reflect the inequalities of the disease in the country.
Resumo:
In acquired immunodeficiency syndrome (AIDS) studies it is quite common to observe viral load measurements collected irregularly over time. Moreover, these measurements can be subjected to some upper and/or lower detection limits depending on the quantification assays. A complication arises when these continuous repeated measures have a heavy-tailed behavior. For such data structures, we propose a robust structure for a censored linear model based on the multivariate Student's t-distribution. To compensate for the autocorrelation existing among irregularly observed measures, a damped exponential correlation structure is employed. An efficient expectation maximization type algorithm is developed for computing the maximum likelihood estimates, obtaining as a by-product the standard errors of the fixed effects and the log-likelihood function. The proposed algorithm uses closed-form expressions at the E-step that rely on formulas for the mean and variance of a truncated multivariate Student's t-distribution. The methodology is illustrated through an application to an Human Immunodeficiency Virus-AIDS (HIV-AIDS) study and several simulation studies.
Resumo:
The aim of this study was to evaluate by photoelastic analysis stress distribution on short and long implants of two dental implant systems with 2-unit implant-supported fixed partial prostheses of 8 mm and 13 mm heights. Sixteen photoelastic models were divided into 4 groups: I: long implant (5 × 11 mm) (Neodent), II: long implant (5 × 11 mm) (Bicon), III: short implant (5 × 6 mm) (Neodent), and IV: short implants (5 × 6 mm) (Bicon). The models were positioned in a circular polariscope associated with a cell load and static axial (0.5 Kgf) and nonaxial load (15°, 0.5 Kgf) were applied to each group for both prosthetic crown heights. Three-way ANOVA was used to compare the factors implant length, crown height, and implant system (α = 0.05). The results showed that implant length was a statistically significant factor for both axial and nonaxial loading. The 13 mm prosthetic crown did not result in statistically significant differences in stress distribution between the implant systems and implant lengths studied, regardless of load type (P > 0.05). It can be concluded that short implants showed higher stress levels than long implants. Implant system and length was not relevant factors when prosthetic crown height were increased.
Resumo:
O objetivo deste estudo foi avaliar as taxas de mortalidade por câncer de boca no período de 1991-2001, no município de Bauru-SP. A fonte de informação utilizada para o reconhecimento e seleção da população-alvo foram Certidões de Óbito dos Cartórios do município de Bauru com dados relativos ao período 1991-2001. Foram coletadas informações referentes a sexo, idade, localização da lesão e endereço. A coleta dos endereços visou à identificação no mapa do município de Bauru da localização geográfica do domicílio. Utilizando ferramentas do geoprocessamento, foi feita a inserção no mapa dos casos identificados. Foram registrados 67 casos de morte por câncer de boca na cidade de Bauru entre 1991 e 2001, com maiores taxas no sexo masculino e sexta década de vida. A análise da distribuição espacial mostra que a maioria dos casos encontra-se próxima à linha férrea que corta o município e foi responsável, em grande parte, pela ocupação territorial pela população, sendo esta também uma área que abrange os bairros mais antigos do município. O câncer de boca constitui importante causa de óbito no município, requerendo um planejamento de ações georreferenciadas pelo sistema local de saúde.
Resumo:
The aim of this study was to evaluate the microbial distribution in the root canal system after periapical lesion induction in dogs' teeth using different methods. Fifty-two root canals were assigned to 4 groups (n=13). Groups I and II: root canals were exposed to the oral cavity for 180 days; groups III and IV: root canals were exposed for 7 days and then the coronal openings were sealed for 53 days. The root apices of groups I and III were perforated, while those of groups II and IV remained intact. After the experimental periods, the animals were euthanized and the anatomic pieces containing the roots were processed and stained with the Brown & Brenn method to assess the presence and distribution of microorganisms. The incidence of microorganisms at different sites of the roots and periapical lesions was analyzed statistically by the chi-square test at 5% significance level. All groups presented microorganisms in the entire root canal system. A larger number of microorganisms was observed on the root canal walls, apical delta and dentinal tubules (p<0.05), followed by cementum and cemental resorption areas. In spite of the different periods of exposure to the oral environment, the methods used for induction of periapical periodontitis yielded similar distribution of microorganisms in the root canal system.
Resumo:
Aggregatibacter actinomycetemcomitans is an important etiologic agent of the periodontitis and is associated with extra-oral infections. In this study, the detection of the ltxA gene as well as the ltx promoter region from leukotoxic A. actinomycetemcomitans isolated from 50 Brazilian patients with periodontitis and 50 healthy subjects was performed. The leukotoxic activity on HL-60 cells was also evaluated. Leukotoxic activity was determined using a trypan blue exclusion method. The 530 bp deletion in the promoter region was evaluated by PCR using a PRO primer pair. A. actinomycetemcomitans was detected by culture and directly from crude subgingival biofilm by PCR using specific primers. By culture, A. actinomycetemcomitans was detected in nine (18%) of the periodontal patients and one (2%) healthy subject. However, by PCR, this organism was detected in 44% of the periodontal patients and in 16% of the healthy subjects. It was verified a great discrepancy between PCR detection of the ltx operon promoter directly from crude subgingival biofilm and from bacterial DNA. Only one periodontal sample harbored highly leukotoxic A. actinomycetemcomitans. Moreover, biotype II was the most prevalent and no correlation between biotypes and leukotoxic activity was observed. The diversity of leukotoxin expression by A. actinomycetemcomitans suggests a role of this toxin in the pathogenesis of periodontal disease and other infectious diseases.