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The distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from mangrove forests of the Rio de Janeiro State was investigated. Ten sampling stations were selected in the mangroves of Sepetiba Bay and the Jacarepaguá Lagoon Complex (JLC), which are areas affected by multiple human activities. The total aliphatic hydrocarbons concentrations showed marked variation between samples (27-407 µg g-1), mostly related to the total organic carbon contents. The total PAHs concentration ranged between 38 and 792 ng g-1. Diagnostic indices and statistical analysis showed that the mangrove forests can be divided into three groups: the western portion of Sepetiba Bay with the lowest level of contamination; the inner portion of the bay with the most intense presence of local sources of contamination, especially of pyrolytic character; and the JLC with a greater accumulation of hydrocarbons, mainly derived from petroleum combustion, resultant from the intense urbanization.

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As of August 2019, several oil slicks reached the Brazilian coast, compromising local ecosystems and the economy of coastal communities. In this context, this study aimed to assess seafood quality at the Canavieiras Extractive Reserve (RESEX), located in the state of Bahia, Northeastern Brazil, by determining polycyclic aromatic hydrocarbons (PAHs) concentrations in local biota following the oil spill. It was designed and carried out in a participatory manner, involving RESEX fishers, shellfish and crab gatherers and managers, as well as university researchers. A total of 72 biota samples were analyzed, and the sum of the 16 priority USEPA PAHs ranged from less than the limit of detection to 30.81 ng g-1 (w.w.). When also considering alkylated compounds, concentrations ranged from 3.53 to 360.75 ng g-1 (w.w.). No sample contained PAHs concentrations suggestive of human consumption risks. No difference in PAHs concentrations between the six studied areas and regarding different biota feeding habits were observed. Higher PAHs concentrations were generally noted in molluscs, as these organisms do not have enzyme systems capable of metabolizing these compounds. This initiative demonstrated the feasibility of participatory construction resulting in a study concerning valued species to local communities, ensuring a contribution to local fishing and marketing activities.

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The leachate pond of a Zn processing plant in Rio de Janeiro, Brazil, released Zn and Cd into a mangrove during three decades. Soil, root, stems, leaves and phloem bark samples of Avicenna schaueriana from the mangrove were collected and analyzed. Zn and Cd levels were measured by atomic absorption and were much more concentrated in soil at 76 kg/ha and 424 kg/ha respectively than in the trees (272.3 kg/ha Zn and 0.046 kg/ha Cd). This species shows a protective mechanism against uptake. The high content of Cd in the bark phloem was due to exposure to tidal flooding with high concentrations of Cd, not translocation from the roots. Allometry, and the biomass of roots, stems, leaves and bark showed that only a small percentage was phytoextracted by A. schaueriana, so this species under the described concentrations cannot phytoaccumulate and should not be used in phytoextraction.

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This essay is a conceptual framework for testing the causal mechanisms of system degradation by metals in the mangrove ecosystem. The Fundão Dam collapse caused massive damage to the marine environment on the Southern Atlantic and Brazilian coast, reaching various kilometers from its origin, becoming a source of contamination. Along this Brazilian coast are vast mangrove areas with high biodiversity, different geomorphology, and distinct ecological functioning. These mangroves support fisheries' productivity in the Tropical South Atlantic, in connection with Abrolhos Reef. Brazil does not have a protocol to monitor environmental damage in this ecosystem, and we proposed to develop a way to identify the impact and quantify it. Along the estuaries, to assess the damage, the plots were demarked in three regions: the upper, middle, and lower estuary, and in both types of forest: fridge and basin. Samples of sediment and leaves were collected bi-monthly to evaluate metal concentrations, especially iron and manganese, the most abundant metals in Fundão Dam. The monitoring also evaluated the forest structure, dynamics of the crabs' population, and flora productivity. First-year monitoring identifies a high concentration of iron or manganese in the sediment above the NOAAs' recommendation in all the estuaries. The concentration of Fe and Mn in sediment varies seasonally in magnitude, concentration, and types of metals between estuaries, sectors, and forests. The behavior of biological indicators in the presence of metals (type and concentration) differed between fauna and flora species. The monitoring recognized that the tailings mining from Fundão Dam impacted all estuaries by different magnitudes and persistence. These differences are due to geomorphology diversity, climate, and oceanographic influences.

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Recent sewage contamination in Brazilian mangrove forests was evaluated using fecal sterols as biomarkers and socioeconomic indicators. The sterols were quantified by gas chromatography/mass spectrometry (GC/MS). Total fecal sterol concentrations ranged between 2.50 2.50 and 39.03 µg g-1 and coprostanol, between 0.23 and 6.97 µg g-1. Mangroves located in less urbanized regions presented low coprostanol levels and low coprostanol/cholesterol and (5ß/5ß + 5α) stanol ratios in sediment, while urban mangrove forests presented moderate fecal contamination. In the latter, an intense contribution of untreated domestic effluents associated to metropolitan areas was noted, leading to a significant correlation between coprostanol concentrations and inadequate sanitation, reflecting environmental problems associated to disorderly urbanization processes coupled to the absence of an adequate urban infrastructure. However, even in metropolitan areas, fecal sterol levels did not reach those of highly contaminated regions, probably due to the intense and accelerated degradation process typical of tropical environments. However, this study highlights the importance of fecal contamination assessment in mangrove areas since the presence of untreated sewage in these ecosystems is an issue of public and environmental health.

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The present study investigated the contamination of Brazilian mangroves sediments by aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs). Samples were obtained from mangroves located along the brazilian coast, between the northern coast and the austral limit of the occurrence of this ecosystem. Total AH ranged from 1.9 to 311.3 µg g-1 and compound distribution pointed to biogenic sources, mainly from mangrove forests, and petrogenic sources, with a significant presence of an unresolved complex mixture in some areas. PAH values (34.4-977.3 ng g-1) indicated low to moderate contamination levels in mangrove sediments, reflecting the socioeconomic diversity observed along the Brazilian coast. The predominant PAH sources ranged from pyrolytic to petrogenic. According to sediment quality reference values, the evaluated sediments are not likely to cause biological effects, but deserve attention due to the current expansion scenario of oil prospecting activities off the Brazilian coast.

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ABSTRACT Studies on belowground roots biomass have increasingly reported the importance of the contribution of this compartment in carbon stock maintenance in mangrove forests. To date, there are no estimates of this contribution in Brazilian mangrove forests, although the country has the second largest area of mangroves worldwide. For this study, trenches dug in fringing forests in Guaratiba State Biological Reserve (Rio de Janeiro, Brazil) were used to evaluate the contribution of the different classes of roots and the vertical stratification of carbon stock. The total carbon stock average in belowground roots biomass in these forests was 104.41 ± 20.73 tC.ha−1. From that, an average of 84.13 ± 21.34 tC.ha−1 corresponded to the carbon stock only in fine roots, which have diameters smaller than 5 mm and are responsible for over 80% of the total belowground biomass. Most of the belowground carbon stock is concentrated in the first 40 cm below the surface (about 70%). The root:shoot ratio in this study is 1.14. These estimates demonstrate that the belowground roots biomass significantly contributes, more than 50%, to the carbon stock in mangrove forests. And the mangrove root biomass can be greater than that of other Brazilian ecosystems.

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Studies on belowground roots biomass have increasingly reported the importance of the contribution of this compartment in carbon stock maintenance in mangrove forests. To date, there are no estimates of this contribution in Brazilian mangrove forests, although the country has the second largest area of mangroves worldwide. For this study, trenches dug in fringing forests in Guaratiba State Biological Reserve (Rio de Janeiro, Brazil) were used to evaluate the contribution of the different classes of roots and the vertical stratification of carbon stock. The total carbon stock average in belowground roots biomass in these forests was 104.41 ± 20.73 tC.ha-1. From that, an average of 84.13 ± 21.34 tC.ha-1 corresponded to the carbon stock only in fine roots, which have diameters smaller than 5 mm and are responsible for over 80% of the total belowground biomass. Most of the belowground carbon stock is concentrated in the first 40 cm below the surface (about 70%). The root:shoot ratio in this study is 1.14. These estimates demonstrate that the belowground roots biomass significantly contributes, more than 50%, to the carbon stock in mangrove forests. And the mangrove root biomass can be greater than that of other Brazilian ecosystems.

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In order to contribute to understand the factors that control the provisioning of the ecosystem service of carbon storage by mangroves, data on carbon stock and sequestration in the aboveground biomass (AGB) from 73 articles were averaged and tested for the dependence on latitude, climatic parameters, physiographic types and age. Global means of carbon stock (78.0 ± 64.5 tC.ha-1) and sequestration (2.9 ± 2.2 tC.ha-1.yr-1) showed that mangroves are among the forest ecosystems with greater capacity of carbon storage in AGB per area. On the global scale, carbon stock increases toward the equator (R²=0.22) and is dependent on 13 climatic parameters, which can be integrated in the following predictive equation: Carbon Stock in AGB = -16.342 + (8.341 x Isothermality) + (0.021 x Annual Precipitation) [R²=0.34; p < 0.05]. It was shown that almost 70% of carbon stock variability is explained by age. Carbon stock and sequestration also vary according to physiographic types, indicating the importance of hydroperiod and edaphic parameters to the local variability of carbon stock. By demonstrating the contribution of local and regional-global factors to carbon stock, this study provides information to the forecast of the effects of future climate changes and local anthropogenic forcings on this ecosystem service.

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ABSTRACT In order to contribute to understand the factors that control the provisioning of the ecosystem service of carbon storage by mangroves, data on carbon stock and sequestration in the aboveground biomass (AGB) from 73 articles were averaged and tested for the dependence on latitude, climatic parameters, physiographic types and age. Global means of carbon stock (78.0 ± 64.5 tC.ha-1) and sequestration (2.9 ± 2.2 tC.ha-1.yr-1) showed that mangroves are among the forest ecosystems with greater capacity of carbon storage in AGB per area. On the global scale, carbon stock increases toward the equator (R²=0.22) and is dependent on 13 climatic parameters, which can be integrated in the following predictive equation: Carbon Stock in AGB = -16.342 + (8.341 x Isothermality) + (0.021 x Annual Precipitation) [R²=0.34; p < 0.05]. It was shown that almost 70% of carbon stock variability is explained by age. Carbon stock and sequestration also vary according to physiographic types, indicating the importance of hydroperiod and edaphic parameters to the local variability of carbon stock. By demonstrating the contribution of local and regional-global factors to carbon stock, this study provides information to the forecast of the effects of future climate changes and local anthropogenic forcings on this ecosystem service.

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Hematite is considered to be the most promising material used as a photoanode for water splitting and here we utilized a sintered hematite photoanode to address the fundamental electrical, electrochemical and photoelectrochemical behavior of this semiconductor oxide. The results presented here allowed us to conclude that the addition of Sn(4+) decreases the grain boundary resistance of the hematite polycrystalline electrode. Heat treatment in a nitrogen (N2) atmosphere also contributes to a decrease of the grain boundary resistance, supporting the evidence that the presence of oxygen is fundamental for the formation of a voltage barrier at the hematite grain boundary. The N2 atmosphere affected both doped and undoped sintered electrodes. We also observed that the heat treatment atmosphere modifies the surface states of the solid-liquid interface, changing the charge-transfer resistance. A two-step treatment, with the second being performed at a low temperature in an oxygen (O2) atmosphere, resulted in a better solid-liquid interface.

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The formation of annual growth rings has been confirmed for several mangrove species in the last decade, among which is the Rhizophora mangle. However, the record of annual rings for this species was made in a region with high hydric seasonality, a widely recognized induction factor of annual rings in tropical species. In this sense, the present study aimed to verify the occurrence of annual growth rings in R. mangle in the mangroves of Guaratiba (Rio de Janeiro, Southeastern Brazil), a region with low hydric seasonality. For this purpose, the crossdating technique was applied in ten trees collected with known age (seven years). The growth rings are characterized by alternating layers of low vessel density (earlywood) and high vessel density (latewood). Multiple regression analysis indicated that growth rings width variation is driven by precipitation, water surplus, water deficit and water storage. Crossdating analysis confirmed the existence of annual growth rings in the R. mangle in Guaratiba. This discovery in a region with low hydric seasonality increases the dendrocronological potential of this species and suggests the importance of biological factors (eg. phenological behavior) as complementary inductors for the formation of growth rings in this species.

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A simple approach to exfoliate and functionalize MoS2 in a single-step is described, which combines the dispersion of MoS2 in polybutadiene solution and ultrasonication processes. The great advantage of this process is that a colloidal stability of MoS2 in nonpolar solvent is achieved by chemically bonding polybutadiene on the perimeter edge sites of MoS2 sheets. In addition, elastomeric nanocomposite has been prepared with singular mechanical properties using functionalized MoS2 as nanofiller in a polybutadiene matrix with a subsequent vulcanization reaction.

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The objective of this study is to report a clinical case of maxillary sinus with lyophilized, xenogeneic graft, in which, despite a large perforation of the sinus membrane, the surgery was not aborted and the results of histological examinations indicate bone neoformation in the surgical area. Results. This case showed that the biomaterials evaluated in this study and the procedure used to place them proved to be biocompatible and presented high osteogenic potential, leading to a successful surgery and osseointegration implant. Conclusion. Positioning Schneider's membrane and filling it with the graft biomaterial helped to achieve the desired osteoconduction and proliferation of bone cells even though the patient had a large perforation of the sinus membrane.

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Com o objetivo de identificar as atitudes dos universitários das redes pública e privada frente ao profissional de limpeza urbana (gari), este estudo apresenta uma pesquisa de campo do tipo descritiva, realizada com 200 estudantes universitários, sendo 100 de uma universidade pública e 100 de uma universidade privada na cidade de João Pessoa-PB. A coleta de dados foi feita por meio de escalas de atitudes, motivação e desejabilidade social, adaptadas, quando preciso, ao ofício de gari e analisadas por meio do pacote estatístico SPSS, em sua versão 15.0 utilizando-se da estatística descritiva e inferencial. Discutem-se temáticas de amplo interesse da Psicologia social, tais como preconceito, atitude, estereótipo e discriminação bem como seus impactos na relação homem-trabalho. Os resultados encontrados revelam que as mulheres são mais conscientes quanto à importância da profissão gari para o bom funcionamento público, bem como que há preconceito nas relações sociais, e, embora este seja expresso de modo sutil, ainda marca negativamente as relações sociais...

Aiming at identifying the attitudes of graduate students from both public and private universities in relation to urban cleaning workers (garbage men), this study presents a descriptive field research carried out with 200 graduate students: 100 from a public university and 100 from a private one in João Pessoa, PB. Data collection was done by means of attitude, motivation and social desirability scales which were adapted, when it was necessary, for the garbage men occupation and then analyzed through the statistical package SPSS for Windows 15.0, using descriptive and inferential statistics. Issues of great interest to social psychology, such as prejudice, attitude, stereotype and discrimination, as well as their impacts in man-work relation were discussed. The results show that women are more aware of the importance of garbage men occupation for proper public functioning and that there is prejudice in the social relations, that although it is expressed in a subtle way, it still plays a negative role in social relations...

Con el objetivo de identificar las actitudes de los universitarios de las redes pública y privada frente al profesional de limpieza urbana (barredor), este estudio presenta una investigación de campo del tipo descriptiva, realizada con 200 estudiantes universitarios, siendo 100 de una universidad pública y 100 de una universidad privada en la ciudad de João Pessoa-PB. La recolección de datos fue realizada por medio de escalas de actitudes, motivación y deseabilidad social, adaptadas, cuando preciso, al oficio de barredor y analizadas por medio del paquete estadístico SPSS, en su versión 15.0 utilizándose de la estadística descriptiva e inferencial. Se discuten temáticas de amplio interés de la Psicología social, tales como prejuicio, actitud, estereotipo y discriminación así como sus impactos en la relación hombre trabajo. Los resultados encontrados revelan que las mujeres son más conscientes en relación a la importancia de la profesión barredor para el buen funcionamiento público, así como que hay prejuicio en las relaciones sociales, y, aunque éste sea expreso de modo sutil, aún marca negativamente las relaciones sociales...

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Com o objetivo de identificar as atitudes dos universitários das redes pública e privada frente ao profissional de limpeza urbana (gari), este estudo apresenta uma pesquisa de campo do tipo descritiva, realizada com 200 estudantes universitários, sendo 100 de uma universidade pública e 100 de uma universidade privada na cidade de João Pessoa-PB. A coleta de dados foi feita por meio de escalas de atitudes, motivação e desejabilidade social, adaptadas, quando preciso, ao ofício de gari e analisadas por meio do pacote estatístico SPSS, em sua versão 15.0 utilizando-se da estatística descritiva e inferencial. Discutem-se temáticas de amplo interesse da Psicologia social, tais como preconceito, atitude, estereótipo e discriminação bem como seus impactos na relação homem-trabalho. Os resultados encontrados revelam que as mulheres são mais conscientes quanto à importância da profissão gari para o bom funcionamento público, bem como que há preconceito nas relações sociais, e, embora este seja expresso de modo sutil, ainda marca negativamente as relações sociais.(AU)

Aiming at identifying the attitudes of graduate students from both public and private universities in relation to urban cleaning workers (garbage men), this study presents a descriptive field research carried out with 200 graduate students: 100 from a public university and 100 from a private one in João Pessoa, PB. Data collection was done by means of attitude, motivation and social desirability scales which were adapted, when it was necessary, for the garbage men occupation and then analyzed through the statistical package SPSS for Windows 15.0, using descriptive and inferential statistics. Issues of great interest to social psychology, such as prejudice, attitude, stereotype and discrimination, as well as their impacts in man-work relation were discussed. The results show that women are more aware of the importance of garbage men occupation for proper public functioning and that there is prejudice in the social relations, that although it is expressed in a subtle way, it still plays a negative role in social relations.(AU)

Con el objetivo de identificar las actitudes de los universitarios de las redes pública y privada frente al profesional de limpieza urbana (barredor), este estudio presenta una investigación de campo del tipo descriptiva, realizada con 200 estudiantes universitarios, siendo 100 de una universidad pública y 100 de una universidad privada en la ciudad de João Pessoa-PB. La recolección de datos fue realizada por medio de escalas de actitudes, motivación y deseabilidad social, adaptadas, cuando preciso, al oficio de barredor y analizadas por medio del paquete estadístico SPSS, en su versión 15.0 utilizándose de la estadística descriptiva e inferencial. Se discuten temáticas de amplio interés de la Psicología social, tales como prejuicio, actitud, estereotipo y discriminación así como sus impactos en la relación hombre trabajo. Los resultados encontrados revelan que las mujeres son más conscientes en relación a la importancia de la profesión barredor para el buen funcionamiento público, así como que hay prejuicio en las relaciones sociales, y, aunque éste sea expreso de modo sutil, aún marca negativamente las relaciones sociales.(AU)

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A complexidade do tratamento definirá a necessidade de uma abordagem interdisciplinar para alcançar resultados de sucesso. Quando se associa perdas dentárias, perda do relacionamento oclusal, mau posicionamento dentário, ao descontrole do estado geral da saúde bucal como, por exemplo, a perda de inserção devido à doença periodontal, a decisão da proposta de tratamento merece cuidados e o prognóstico de uma etapa do tratamento depende do su- cesso de outra. Desta forma, no caso a seguir, as disciplinas de Ortodontia do Departamento de Ortodontia e Odontopediatria e de Clínica Integrada do Departamento de Estomatologia da Faculdade de Odontologia da Universidade de São Paulo (Fousp), de maneira interdisciplinar, foram determinantes para o sucesso da reabilitação do paciente. Após a fase de controle da saúde bucal iniciou-se o tratamento ortodôntico fixo em ambas as arcadas. Concluída a movimentação dentária com fechamento dos diastemas e nivelamento oclusal (cerca de 24 meses) e sua manutenção, iniciou-se a fase reabilitadora do tratamento, com um minucioso estudo com a finalidade de apresentar alternativas para o tratamento protético.

The complexity of the treatment will define the necessity of an interdisciplinary approach to achieve successful results. The association between tooth loss, loss of occlusal relationship, bad teeth positioning, with the lack of the general state of oral health such as insertion loss due to periodontal disease, the decision of the proposed treatment deserves care and prognosis of a stage of treatment depends on the success of a nother. Th us, i n the followi ng case, the Orthodontics Department of Orthodontics and Pediatric Dentistry and Integrated Clinic, Department of Stomatology, School of Dentistry, University of São Paulo, in an interdisciplinary way, were crucial to the success of rehabilitation. After the stage of the oral health control began the fixed orthodontic treatment in both arches. Complete tooth movement with diastemas resolution and occlusalleveling (about 24 months) and their maintenance, the rehabilitative phase of treatment started, with a detailed study with the purpose of presenting of prosthetic treatment alternatives.

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OBJECTIVE: The aim of this study was to evaluate the need for antibiotic prescription in third molar surgery. STUDY DESIGN: A double-blind randomized study was carried out with 71 patients from CODONT (Dentistry Center of the Police of São Paulo). Amoxicillin, clindamycin, or no medication was administered for 7 days immediately after surgery. The participants evaluated the presence of pain, edema, interincisal distance (ID), presence of infection, Pell and Gregory classification, rescue analgesia, osteotomy, and odontosection. RESULTS: There was no difference (P < .05) between antibiotics and control over the surgery duration, dose, visual analog scale (VAS), ID, and edema, yet significant differences were seen over time for VAS, edema, and ID. CONCLUSIONS: Antibiotic prescription should not be indicated in all clinical conditions, yet it is necessary to correctly evaluate factors such as systemic condition of the patient, skill of the operator, and contamination of the surgical environment.

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PURPOSE: The study aimed to assess electrocardiographic alterations during oral implant placement surgeries under local anesthesia (lidocaine chlorhydrate with epinephrine), using 15 mg of midazolam as an anxiolytic premedication. MATERIAL AND METHODS: The study randomly selected 20 patients, aged 21-50 years old, requiring bilateral mandibular dental implants. Each patient was assessed using placebo on one side and midazolam on the contralateral side, with random, double-blinded distribution. The electrocardiogram recorded 12 static leads every 2 min, while D2 derivations were recorded continuously. RESULTS: No statistically significant differences were observed between the placebo and midazolam when analyzing the morphological behavior of the electrocardiographic wave and the presence of arrhythmias during the experiment. However, under sedation, assessment of the behavior of electrocardiographic parameters during different stages of the procedure revealed statistically significant differences (P<0.05) for heart rate, P-wave amplitude and duration of the RR and QTc intervals. The arrhythmias detected were considered low risk for patients without systemic alterations and were observed in 53.3% of patients. The most frequently occurring alterations were tachycardia, bradycardia, supraventricular and ventricular extrasystoles and blocked atrial extrasystole, which were similar for both placebo and midazolam, with the greatest incidence during the initial, incision and bone drilling stages. CONCLUSION: The use of 15 mg of midazolam made no difference compared with the placebo. The use of 15 mg of midazolam did not show an advantage in the incidence of arrhythmias The anxiolytic premedication does not prevent myocardial arrhythmias in endosseous implant placement. The clinical significance of the arrhythmias may not represent serious risks.

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This study evaluated fracture torque by torsion, in relation to the length and diameter of orthodontic mini-implants, to demonstrate their viability for clinical and experimental use based on the torque recommended by the manufacturers. The fractures at the moment of insertion, whose incidence in the literature is around 4%, are principally due to excessive force and the inability of the implant to resist rotational forces. Thirty orthodontic mini-implants of three commercial brands available in Brazil (Neodent 1.6 x 9 mm, Dentoflex 1.6 x 9 mm and Kopp 1.6 x 9 mm) were attached to a device made specifically for this research, leaving the mini-implants with sufficient stability. The miniimplants were submitted to torsion torque, using a digital torque wrench, until their breaking point. The values obtained with the test were submitted to analysis of variance and the Tukey test. The mean values of mini-implant ruptures were 26 N.cm for group A (Dentoflex), 25.4 N. cm for group B (Kopp) and 32.8 N.cm for group C (Neodent). From the Tukey test we could observe that the relationships between the means of the Dentoflex and Neodent groups, and between the Kopp and Neodent groups, were significant. Between the Dentoflex and Kopp groups, significance was nonexistent. All the values found in our research for fracture torque were higher than the limits recommended by the manufacturers for clinical use in orthodontics. The highest values were found in the Neodent group.

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