926 resultados para Praial and estuarine system.


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The sexual system of the symbiotic shrimp Thor amboinensis is described, along with observations on sex ratio and host-use pattern of different populations. We used a comprehensive approach to elucidate the previously unknown sexual system of this shrimp. Dissections, scanning electron microscopy, size-frequency distribution analysis, and laboratory observations demonstrated that T amboinensis is a protandric hermaphrodite: shrimp first mature as males and change into females later in life. Thor amboinensis inhabited the large and structurally heterogeneous sea anemone Stichoclactyla helianthus in large groups (up to 11 individuals) more frequently than expected by chance alone. Groups exhibited no particularly complex social structure and showed male-biased sex ratios more frequently than expected by chance alone. The adult sex ratio was male-biased in the four separate populations studied, one of them being thousands of kilometers apart from the others. This study supports predictions central to theories of resource monopolization and sex allocation. Dissections demonstrated that unusually large males were parasitized by an undescribed species of isopod (family Entoniscidae). Infestation rates were similarly low in both sexes (approximate to 11%-12%). The available information suggests that T. amboinensis uses pure search promiscuity as a mating system. This hypothesis needs to be formally tested with mating behavior observations and field measurements on the movement pattern of both sexes of the species. Further detailed studies on the lifestyle and sexual system of all the species within this genus and the development of a molecular phylogeny are necessary to elucidate the evolutionary history of gender expression in the genus Thor.

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In Sweden, 90% of the solar heating systems are solar domestic hot water and heating systems (SDHW&H), so called combisystems. These generally supply most of the domestic hot water needs during the summer and have enough capacity to supply some energy to the heating system during spring and autumn. This paper describes a standard Swedish combisystem and how the output from it varies with heating load, climate within Sweden, and how it can be increased with improved system design. A base case is defined using the standard combi- system, a modern Swedish single family house and the climate of Stockholm. Using the simulation program Trnsys, parametric studies have been performed on the base case and improved system designs. The solar fraction could be increased from 17.1% for the base case to 22.6% for the best system design, given the same system size, collector type and load. A short analysis of the costs of changed system design is given, showing that payback times for additional investment are from 5-8 years. Measurements on system components in the laboratory have been used to verify the simulation models used. More work is being carried out in order to find even better system designs, and further improvements in system performance are expected.

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An international standard, ISO/DP 9459-4 has been proposed to establish a uniform standard of quality for small, factory-made solar heating systerns. In this proposal, system components are tested separatelyand total system performance is calculated using system simulations based on component model parameter values validated using the results from the component tests. Another approach is to test the whole system in operation under representative conditions, where the results can be used as a measure of the general system performance. The advantage of system testing of this form is that it is not dependent on simulations and the possible inaccuracies of the models. Its disadvantage is that it is restricted to the boundary conditions for the test. Component testing and system simulation is flexible, but requires an accurate and reliable simulation model.The heat store is a key component conceming system performance. Thus, this work focuses on the storage system consisting store, electrical auxiliary heater, heat exchangers and tempering valve. Four different storage system configurations with a volume of 750 litre were tested in an indoor system test using a six -day test sequence. A store component test and system simulation was carried out on one of the four configurations, applying the proposed standard for stores, ISO/DP 9459-4A. Three newly developed test sequences for intemalload side heat exchangers, not in the proposed ISO standard, were also carried out. The MULTIPORT store model was used for this work. This paper discusses the results of the indoor system test, the store component test, the validation of the store model parameter values and the system simulations.

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In Sweden, there are about 0.5 million single-family houses that are heated by electricity alone, and rising electricity costs force the conversion to other heating sources such as heat pumps and wood pellet heating systems. Pellet heating systems for single-family houses are currently a strongly growing market. Future lack of wood fuels is possible even in Sweden, and combining wood pellet heating with solar heating will help to save the bio-fuel resources. The objectives of this thesis are to investigate how the electrically heated single-family houses can be converted to pellet and solar heating systems, and how the annual efficiency and solar gains can be increased in such systems. The possible reduction of CO-emissions by combining pellet heating with solar heating has also been investigated. Systems with pellet stoves (both with and without a water jacket), pellet boilers and solar heating have been simulated. Different system concepts have been compared in order to investigate the most promising solutions. Modifications in system design and control strategies have been carried out in order to increase the system efficiency and the solar gains. Possibilities for increasing the solar gains have been limited to investigation of DHW-units for hot water production and the use of hot water for heating of dishwashers and washing machines via a heat exchanger instead of electricity (heat-fed appliances). Computer models of pellet stoves, boilers, DHW-units and heat-fed appliances have been developed and the parameters for the models have been identified from measurements on real components. The conformity between the models and the measurements has been checked. The systems with wood pellet stoves have been simulated in three different multi-zone buildings, simulated in detail with heat distribution through door openings between the zones. For the other simulations, either a single-zone house model or a load file has been used. Simulations were carried out for Stockholm, Sweden, but for the simulations with heat-fed machines also for Miami, USA. The foremost result of this thesis is the increased understanding of the dynamic operation of combined pellet and solar heating systems for single-family houses. The results show that electricity savings and annual system efficiency is strongly affected by the system design and the control strategy. Large reductions in pellet consumption are possible by combining pellet boilers with solar heating (a reduction larger than the solar gains if the system is properly designed). In addition, large reductions in carbon monoxide emissions are possible. To achieve these reductions it is required that the hot water production and the connection of the radiator circuit is moved to a well insulated, solar heated buffer store so that the boiler can be turned off during the periods when the solar collectors cover the heating demand. The amount of electricity replaced using systems with pellet stoves is very dependant on the house plan, the system design, if internal doors are open or closed and the comfort requirements. Proper system design and control strategies are crucial to obtain high electricity savings and high comfort with pellet stove systems. The investigated technologies for increasing the solar gains (DHW-units and heat-fed appliances) significantly increase the solar gains, but for the heat-fed appliances the market introduction is difficult due to the limited financial savings and the need for a new heat distribution system. The applications closest to market introduction could be for communal laundries and for use in sunny climates where the dominating part of the heat can be covered by solar heating. The DHW-unit is economical but competes with the internal finned-tube heat exchanger which is the totally dominating technology for hot water preparation in solar combisystems for single-family houses.

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A new paradigm is modeling the World: evolutionary innovations in all fronts, new information technologies, huge mobility of capital, use of risky financial tools, globalization of production, new emerging powers and the impact of consumer concerns on governmental policies. These phenomena are shaping the World and forcing the advent of a new World Order in the Multilateral Monetary, Financial, and Trading System. The effects of this new paradigm are also transforming global governance. The political and economic orders established after the World War and centered on the multilateral model of UN, IMF, World Bank, and the GATT, leaded by the developed countries, are facing significant challenges. The rise of China and emerging countries shifted the old model to a polycentric World, where the governance of these organizations are threatened by emerging countries demanding a bigger participation in the role and decision boards of these international bodies. As a consequence, multilateralism is being confronted by polycentrism. Negotiations for a more representative voting process and the pressure for new rules to cope with the new demands are paralyzing important decisions. This scenario is affecting seriously not only the Monetary and Financial Systems but also the Multilateral Trading System. International trade is facing some significant challenges: a serious deadlock to conclude the last round of the multilateral negotiation at the WTO, the fragmentation of trade rules by the multiplication of preferential and mega agreements, the arrival of a new model of global production and trade leaded by global value chains that is threatening the old trade order, and the imposition of new sets of regulations by private bodies commanded by transnationals to support global value chains and non-governmental organizations to reflect the concerns of consumers in the North based on their precautionary attitude about sustainability of products made in the World. The lack of any multilateral order in this new regulation is creating a big cacophony of rules and developing a new regulatory war of the Global North against the Global South. The objective of this paper is to explore how these challenges are affecting the Tradinge System and how it can evolve to manage these new trends.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Background: In 2000, the eight Millennium Development Goals (MDGs) set targets for reducing child mortality and improving maternal health by 2015.Objective: To evaluate the results of a new education and referral system for antenatal/intrapartum care as a strategy to reduce the rates of Cesarean sections (C-sections) and maternal/perinatal mortality.Methods: Design: Cross-sectional study. Setting: Department of Gynecology and Obstetrics, Botucatu Medical School, São Paulo State University/UNESP, Brazil. Population: 27,387 delivering women and 27,827 offspring. Data collection: maternal and perinatal data between 1995 and 2006 at the major level III and level II hospitals in Botucatu, Brazil following initiation of a safe motherhood education and referral system. Main outcome measures: Yearly rates of C-sections, maternal (/100,000 LB) and perinatal (/1000 births) mortality rates at both hospitals. Data analysis: Simple linear regression models were adjusted to estimate the referral system's annual effects on the total number of deliveries, C-section and perinatal mortality ratios in the two hospitals. The linear regression were assessed by residual analysis (Shapiro-Wilk test) and the influence of possible conflicting observations was evaluated by a diagnostic test (Leverage), with p < 0.05.Results: Over the time period evaluated, the overall C-section rate was 37.3%, there were 30 maternal deaths (maternal mortality ratio = 109.5/100,000 LB) and 660 perinatal deaths (perinatal mortality rate = 23.7/1000 births). The C-section rate decreased from 46.5% to 23.4% at the level II hospital while remaining unchanged at the level III hospital. The perinatal mortality rate decreased from 9.71 to 1.66/1000 births and from 60.8 to 39.6/1000 births at the level II and level III hospital, respectively. Maternal mortality ratios were 16.3/100,000 LB and 185.1/100,000 LB at the level II and level III hospitals. There was a shift from direct to indirect causes of maternal mortality.Conclusions: This safe motherhood referral system was a good strategy in reducing perinatal mortality and direct causes of maternal mortality and decreasing the overall rate of C-sections.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Purpose: This study evaluated the bond strength of two etch-and-rinse adhesive systems (two- and three-step) and a self-etching system to Coronal and root canal dentin.Materials and Methods: The root canals of 30 human incisors and canines were instrumented and prepared with burs. The posts used for luting were duplicated with dual resin cement (Duo-link) inside Aestheti Plus #2 molds. Thus, three groups were formed (n = 10) according to the adhesive system employed: All-Bond 2 (TE3) + resin cement post (rcp) + Duo-link (DI); One-Step Plus (TE2) + rcp + DI; Tyrian/One-Step Plus (SE) + rcp + DI. Afterwards, 8 transverse sections (1.5 mm) were cut from 4 mm above the CEJ up to 4 mm short of the root canal apex, comprising coronal and root canal dentin. The sections were submitted to push-out testing in a universal testing machine EMIC (1 mm/min). Bond strength data were analyzed with two-way repeated measures ANOVA and Tukey's test (p < 0.05).Results: The relationship between the adhesives was not the same in the different regions (p < 0.05). Comparison of the means achieved with the adhesives in each region (Tukey; p < 0.05) revealed that TE3 (mean standard deviation: 5.22 +/- 1.70) was higher than TE2 (2.60 +/- 1.74) and SE (1.68 +/- 1.85).Conclusion: Under the experimental conditions, better bonding to dentin was achieved using the three-step etch-and-rinse system, especially in the coronal region. Therefore, the traditional etch-and-rinse three-step adhesive system seems to be the best choice for teeth needing adhesive endodontic restorations.

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This study presents an environmental oil spill sensitivity map of Cardoso Island State Park, located in São Paulo state, Brazil, including some of its surrounding areas. This map was designed following the procedures determined by the Brazilian Federal Environment Organ (Ministry of the Environment), which separates coastal habitats in different littoral sensitivity indexes (LSI) to oil spills. We have also analysed some seasonal variations in morphologic and textural parameters at the local marine beaches that could affect their sensitivity, having found that they are more sensitive during summer due to a wider foreshore zone during these periods. Local most sensitive habitats are estuarine mangroves (LSI 10) and estuarine mud banks (LSI 9). Marine beaches were ranked LSI 3, and littoral rocky shores were subdivided in exposed flat rocky shores (LSI 1), boulder rocky shores (LSI 6) and sheltered rocky shores (LSI 8). Due to the elevated sensitivity of an estuarine system in the area, we considered necessary the installation of an Environmental Emergency Centre and the design of an emergency plan for the region in case of an accident resulting in oil spills within its vicinities. (C) 2007 Elsevier Ltd. All rights reserved.

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In this work, a preconcentration and separation system based on continuous flow hydride generation is proposed to improve the determination of As and Se by total reflection X-ray fluorescence spectrometry. The generated hydrides are continuously separated from the liquid phase and collected in a chamber containing 250 mul of HCI/HNO3 1:1 (v/v) solution. Hydride generation conditions and collection of the hydrides were evaluated. Under optimised conditions, enrichment factors of 55 for As and 82 for Se were attained. Detection limits of 0.3 mug l(-1) for As and Se were obtained when 20 ml of sample was used. Analysis of a natural water standard reference material from National Institute of Standard and Technology (SRM-1640) was in agreement with the certified values at the 95% confidence level. (C) 2004 Elsevier B.V. All rights reserved.

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Two foraminiferal associations comprising only arenaceous species define two distinct environments in a 340 m-long mangrove transect at Cardoso Island, Trapande Bay (Cananeia-Iguape estuarine system, SP, Brazil). The "lower muddy flat" (LMF), from the outer mangrove fringe inwards towards land (100 m), is positioned in the lower plain between 0.04 and 0.23 m above the mean sea level (msl), and remains subaerially exposed between 48.5 and 65.6% of the time. This environment is characterized by higher foraminiferal diversity and evenness (McIntosh's D = 0.54 [plus or minus] 0.21 and Pielou's E = 0.68 [plus or minus] 0.25, respectively) and is dominated by Arenoparrella mexicana and Trochammina inflata, and to a lesser extent by Ammotium directum and Textularia earlandi. The mangrove plant of this segment is a Rhizophoretum with average height of 8.4 [plus or minus] 1.2 m. The sediment is characterized by higher concentration of organic matter (93.5 [plus or minus] 32.3 g dm-3) and metals (e.g. V = 53.4 [plus or minus] 21.8 ppm and Zn = 46.4 [plus or minus] 21.3 ppm). The "upper sandy flat" (USF), 240 m wide along the transect, is positioned in the upper plain between 0.28 and 0.89 m above the msl, and remains subaerially exposed between 69.7 and 98.5% of the time. This environment is characterized by a lower diversity and evenness (D = 0.33 [plus or minus] 0.17 and E = 0.49 [plus or minus] 0.20, respectively). The association is dominated by species T. inflata and Miliammina fusca. The Rhizophoretum exhibits a lower average height of 3.6 [plus or minus] 0.6 m. The sediment is poorer in organic matter (39.3 [plus or minus] 15.0 g dm-3) and metals (e.g. V = 13.0 [plus or minus] 6.8 ppm and Zn = 6.9 [plus or minus] 3.7 ppm). Whereas "elongate" tests (uniserial, biserial and planospiral followed by a uniserial portion) are restricted to the LMF, "spiraled" species dominate the USF. Subaerial exposure time seems to exert a primary influence on species distribution, in addition to salinity and sediment type. Species may be adapted to different exposure times, a factor dependent on their position on the intertidal zone and the tidal regime, which should be taken into account in relative sea level reconstructions based on intertidal foraminifera. These patterns have important implications for studies investigating the ecology and paleoecology of foraminifera and subtle fluctuations in relative sea level during the Quaternary.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This work aimed to study the bacterial contamination in stings of the catfish Genidens genidens and Cathorops agassizii found in the São Vicente estuarine system (São Paulo State, Brazil). For bacteriological analyses, we used fish samples distributed into a group of 50 specimens (25 C. agassizii and 25 G. genidens) and a group of 14 specimens (7 C. agassizii and 7 G. genidens). Results showed contamination of 13 different bacterial species of Enterobacteriaceae, being Klebsiella pneumoniae the most frequent bacteria (26.80%) followed by Enterobacter sp and Escherichia coli (16.27%), and Serratia marcescens, Serratia sp. and Proteus mirabilis (1.16%). Gram-positive bacteria as well as fungi were not detected in the samples. According to the Gram-negative species characterized and with regard to the environmental conditions, it can also be considered that accidents with these catfish stings may develop significant acute secondary infections in humans.