990 resultados para Monitoring. beach profiles. Ponta Negra. Sedimentology. Hydrodynamics


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Increased tourist activity in coastal regions demands management strategies to reduce impacts on rocky shores. The highly populated coastal areas in southeastern Brazil are an example of degradation caused by development of industry and tourism. Among different shore impacts, trampling has been intensively studied, and may represent a significant source of stress for intertidal fauna. A randomised blocks design was applied to experimentally study the effects of two different trampling intensities on richness, diversity, density and biomass of the rocky shore fauna of Obuseiro beach, Guarujá, southeastern Brazil. Blocks were distributed in two portions of the intertidal zone, dominated respectively by Chthamalus bisinuatus (Cirripedia) and Isognomon bicolor (Bivalvia). Blocks were trampled over three months, simulating the vacation period in Brazil and were monitored for the following nine months. Results indicate that Chthamalus bisinuatus is vulnerable to trampling impacts. Richness, diversity and turn-over index tended to be higher in trampled plots four months after trampling ceased. In general, results agree with previous trampling studies, suggesting that even low intensities of trampling may cause some impact on intertidal communities. Management strategies should include isolation of sensitive areas, construction of boardwalks, visitor education and monitoring programmes. In Brazil, additional data obtained from experimental studies are necessary in order to achieve a better understanding of trampling impacts on rocky shore communities.

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The tolerance to the combined effects of temperature and salinity was investigated in the interstitial isopod Coxicerberus ramosae (Albuquerque, 1978), a species of intertidal zone of sandy beaches in Rio de Janeiro, Brazil. The animals were collected on Praia Vermelha Beach. The experiments lasted 24 h and nine salinities and seven temperatures were used for a total of 63 combinations. Thirty animals were tested in each combination. The species showed high survival in most of the combinations. The temperature of 35 ºC was lethal and at 5 ºC, the animals tolerated only a narrow range of salinities. The statistical analyses showed that the effects of temperature and salinity were significant on the survival, which confirmed the euryhalinity and eurythermy of this species.

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The photocatalytic degradation of phenol in aqueous suspensions of TiO2 under different salt concentrations in an annular reactor has been investigated. In all cases, complete removal of phenol and mineralization degrees above 90% were achieved. The reactor operational parameters were optimized and its hydrodynamics characterized in order to couple mass balance equations with kinetic ones. The photodegradation of the organics followed a Langmuir-Hinshelwood-Hougen-Watson lumped kinetics. From GC/MS analyses, several intermediates formed during oxidation have been identified. The main ones were catechol, hydroquinone, and 3-phenyl-2-propenal, in this order. The formation of negligible concentrations of 4-chlorophenol was observed only in high salinity medium. Acute toxicity was determined by using Artemia sp. as the test organism, which indicated that intermediate products were all less toxic than phenol and a significant abatement of the overall toxicity was accomplished, regardless of the salt concentration.

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Atherinella blackburni is a silverside species whose occurrence on the Brazilian coast was not properly registered until recently. So far, records of its distribution along the Brazilian shore were limited to Itaparica Island, Bahia State, and Porto Inhaúma, Rio de Janeiro State. In a recent survey of the ichthyofauna of Itamambuca Beach, Ubatuba, São Paulo State, 100 specimens of this species were collected, yielding a considerable source of information regarding its ecology and a new southern limit of its distribution. A detailed survey of an ichthyological collection revealed lots of this species from regions of the Brazilian Northeast, resulting in a northward expansion of the occurrence of A. blackburni in Brazilian waters. Besides the populations found on the Brazilian coast, the species also occurs discontinuously in the Atlantic coasts of Costa Rica, Panama and Venezuela. Meristic and morphometric analysis showed overlapped values between Brazilian populations and the ones closer to the Caribbean. An ecological study of A. blackburni at Itamambuca Beach revealed that it is a predominantly diurnal species with preference for warm and salty waters, often occurring in sandy-bottom environments. It was more abundant in Summer and Winter, when individuals with smaller values of length and weight also occurred.

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Sandy beaches are among the most extensive environments in Brazil and are generally threatened by disorderly urban growth due to their location along the coast, where human populations tend to concentrate. This is especially true in southeastern Brazil, where the largest urban areas are located. Thus, better knowledge regarding these natural resources is of considerable importance. The surf zone of sandy beaches is inhabited by a number of fish species, including juveniles seeking both food and shelter from predators. An ecological survey was conducted in the surf zone of Itamambuca beach in the city of Ubatuba, São Paulo State, Brazil, in order to evaluate the composition, structure and dynamics of the fish fauna using community descriptors. Diurnal and nocturnal samples were taken with a beach seine at five oceanographic stations over a 12-month period. Water temperature and salinity were also recorded. A total of 2,147 individuals representing 34 species and 18 families were sampled. The main variation in fish fauna was detected on the diel level, followed by a spatial repartition possibly related to salinity. Seasonal variation was also observed. The five most important species in the overall context were Atherinella brasiliensis, Eucinostomus melanopterus, Mugil sp., Trachinotus goodei and Atherinella blackburni.

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This paper presents the results of the planform stability classification for the headland-bay beaches of the State of Santa Catarina and of the Northern Coast of São Paulo, based on the application of the Parabolic Bay-Shape Equation (PBSE) to aerial images of the beaches, using the software MEPBAY®. For this purpose, georeferenced mosaics of the QuickBird2® satellite imagery (for the State of Santa Catarina) and vertical aerial photographs (for the northern coast of São Paulo State) were used. Headland-bay beach planform stability can be classified as: (1) in static equilibrium, (2) in dynamic equilibrium, (3) unstable or (4) in a state of natural beach reshaping. Static equilibrium beaches are the most frequent along the coast of the State of Santa Catarina and the Northern Shore of São Paulo, notably along the most rugged sectors of the coast and those with experiencing lower fluvial discharge. By comparison, dynamic equilibrium beaches occur primarily on the less rugged sectors of the coast and along regions with higher fluvial discharge. Beaches in a state of natural beach reshaping have only been found in SC, associated with stabilized estuarine inlets or port breakwaters. However, it is not possible to classify any of these beaches as unstable because only one set of images was used. No clear relation was observed between a beach's planform stability and other classification factors, such as morphodynamics or orientation.

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Estuarine hydrodynamics is a key factor in the definition of the filtering capacity of an estuary and results from the interaction of the processes that control the inlet morphodynamics and those that are acting in the mixing of the water in the estuary. The hydrodynamics and suspended sediment transport in the Camboriú estuary were assessed by two field campaigns conducted in 1998 that covered both neap and spring tide conditions. The period measured represents the estuarine hydrodynamics and sediment transport prior to the construction of the jetty in 2003 and provides important background information for the Camboriú estuary. Each field campaign covered two complete tidal cycles with hourly measurements of currents, salinity, suspended sediment concentration and water level. Results show that the Camboriú estuary is partially mixed with the vertical structure varying as a function of the tidal range and tidal phase. The dynamic estuarine structure can be balanced between the stabilizing effects generated by the vertical density gradient, which produces buoyancy and stratification flows, and the turbulent effects generated by the vertical velocity gradient that generates vertical mixing. The main sediment source for the water column are the bottom sediments, periodically resuspended by the tidal currents. The advective salt and suspended sediment transport was different between neap and spring tides, being more complex at spring tide. The river discharge term was important under both tidal conditions. The tidal correlation term was also important, being dominant in the suspended sediment transport during the spring tide. The gravitational circulation and Stokes drift played a secondary role in the estuarine transport processes.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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A hydrodynamic characterization of the Itapocu river and Barra Velha lagoon estuarine system was carried out with the objective of evaluating how the current regime in this area is affected by astronomical and meteorological tides and the river discharge. Meteorological, water level and current velocity and direction data were gathered hourly during a twenty-day period, from 22-July until 10-August, 2004. Current meters were positioned at the inlet, at the entrance of the north and south lagoons and at the lower estuary of the river along with a tide gauge. The estuarine system showed distinct current behavior among the different sectors within the estuary, responding to the different forcings. The strongest currents were observed at the inlet while the weakest values were observed at the northern lagoon, a location that showed little dynamic. The general flow was ebb-dominated flux, in response to fluvial discharge, even during local wind water set-up event.

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The study objective was to evaluate the feasibility of interviews by cell phone as a complement to interviews by landline to estimate risk and protection factors for chronic non-communicable diseases. Adult cell phone users were evaluated by random digit dialing. Questions asked were: age, sex, education, race, marital status, ownership of landline and cell phones, health condition, weight and height, medical diagnosis of hypertension and diabetes, physical activity, diet, binge drinking and smoking. The estimates were calculated using post-stratification weights. The cell phone interview system showed a reduced capacity to reach elderly and low educated populations. The estimates of the risk and protection factors for chronic non-communicable diseases in cell phone interviews were equal to the estimates obtained by landline phone. Eligibility, success and refusal rates using the cell phone system were lower than those of the landline system, but loss and cost were much higher, suggesting it is unsatisfactory as a complementary method in such a context.

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The Healthy Cities and Agenda 21 programs improve living and health conditions and affect social and economic determinants of health. The Millennium Development Goals (MDG) indicators can be used to assess the impact of social agendas. A data search was carried out for the period 1997 to 2006 to obtain 48 indicators proposed by the United Nations and a further 74 proposed by the technical group for the MDGin Brazil. There is a scarcity of studies concerned with assessing the MDG at the municipal level. Data from Brazilian health information systems are not always consistent or accurate for municipalities. The lack of availability and reliable data led to the substitution of some indicators. The information systems did not always provide annual data; national household surveys could not be disaggregated at the municipal level and there were also modifications on conceptual definitions over time. As a result, the project created an alternative list with 29 indicators. MDG monitoring at the local community can be important to measure the performance of actions toward improvements in quality of life and social iniquities.

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Este estudo teve por objetivo identificar o risco e os fatores associados à mortalidade materna de multigestas (cinco ou mais gestações). Descreve a tendência da Taxa de Fecundidade Total (TFT) e da Razão de Mortalidade Materna (RMM) de 1998 a 2004 no Paraná. Apresenta uma análise dos 822 óbitos maternos deste período, o cálculo da Razão de Mortalidade Materna Específica, o Risco Relativo, a freqüência e o Odds Ratio para algumas variáveis segundo número de gestações. Analisa também as causas e a evitabilidade dos óbitos maternos. Os resultados apontaram TFT baixa (1,8 filhos por mulher) e a RMM elevada (69,7/100.000 nascidos vivos) no Paraná em 2004. Um quarto dos 822 óbitos maternos (206) era de multigestas (cinco ou mais gestações), o risco relativo de morte materna foi seis vezes superior do que para as mulheres com até duas gestações, e os perfis sociodemográfico e o reprodutivo foram mais desfavoráveis para aquele grupo de mulheres. A baixa escolaridade, a idade igual ou acima de 30 anos e o pré-natal com menos de quatro consultas apresentaram associação com o maior número de gestações. A proporção de mortes por causas obstétricas indiretas, hemorragias e aborto, foi maior entre as multigestas, e cerca de 90% dos óbitos deste grupo foi considerado evitável. Concluiu-se que o monitoramento das multigestas com idade avançada e em desvantagem social, bem como ações efetivas de planejamento familiar, e serviços obstétricos qualificados para gestação de alto risco são medidas que podem contribuir para a redução da mortalidade materna

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This paper proposes an architecture for machining process and production monitoring to be applied in machine tools with open Computer numerical control (CNC). A brief description of the advantages of using open CNC for machining process and production monitoring is presented with an emphasis on the CNC architecture using a personal computer (PC)-based human-machine interface. The proposed architecture uses the CNC data and sensors to gather information about the machining process and production. It allows the development of different levels of monitoring systems with mininium investment, minimum need for sensor installation, and low intrusiveness to the process. Successful examples of the utilization of this architecture in a laboratory environment are briefly described. As a Conclusion, it is shown that a wide range of monitoring solutions can be implemented in production processes using the proposed architecture.

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Background: MicroRNA (miR) are a class of small RNAs that regulate gene expression by inhibiting translation of protein encoding transcripts. To evaluate the role of miR in skeletal muscle of swine, global microRNA abundance was measured at specific developmental stages including proliferating satellite cells, three stages of fetal growth, day-old neonate, and the adult. Results: Twelve potential novel miR were detected that did not match previously reported sequences. In addition, a number of miR previously reported to be expressed in mammalian muscle were detected, having a variety of abundance patterns through muscle development. Muscle-specific miR-206 was nearly absent in proliferating satellite cells in culture, but was the highest abundant miR at other time points evaluated. In addition, miR-1 was moderately abundant throughout developmental stages with highest abundance in the adult. In contrast, miR-133 was moderately abundant in adult muscle and either not detectable or lowly abundant throughout fetal and neonate development. Changes in abundance of ubiquitously expressed miR were also observed. MiR-432 abundance was highest at the earliest stage of fetal development tested (60 day-old fetus) and decreased throughout development to the adult. Conversely, miR-24 and miR-27 exhibited greatest abundance in proliferating satellite cells and the adult, while abundance of miR-368, miR-376, and miR-423-5p was greatest in the neonate. Conclusion: These data present a complete set of transcriptome profiles to evaluate miR abundance at specific stages of skeletal muscle growth in swine. Identification of these miR provides an initial group of miR that may play a vital role in muscle development and growth.

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Background: The Borg Scale may be a useful tool for heart failure patients to self-monitor and self-regulate exercise on land or in water (hydrotherapy) by maintaining the heart rate (HR) between the anaerobic threshold and respiratory compensation point. Methods and Results: Patients performed a cardiopulmonary exercise test to determine their anaerobic threshold/respiratory compensation points. The percentage of the mean HR during the exercise session in relation to the anaerobic threshold HR (%EHR-AT), in relation to the respiratory compensation point (%EHR-RCP), in relation to the peak HR by the exercise test (%EHR-Peak) and in relation to the maximum predicted HR (%EHR-Predicted) was calculated. Next, patients were randomized into the land or water exercise group. One blinded investigator instructed the patients in each group to exercise at a level between ""relatively easy and slightly tiring"". The mean HR throughout the 30-min exercise session was recorded. The %EHR-AT and %EHR-Predicted did not differ between the land and water exercisegroups, but they differed in the %EHR-RCP (95 +/- 7 to 86 +/- 7. P<0.001) and in the %EHR-Peak (85 +/- 8 to 78 +/- 9, P=0.007). Conclusions: Exercise guided by the Borg scale maintains the patient's HR between the anaerobic threshold and respiratory compensation point (ie, in the exercise training zone). (Circ J 2009; 73: 1871-1876)