154 resultados para <3.9 µm


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Total (HgT), reactive (HgR) and organic (Hg ORG) mercury species have been quantified in non-filtered waters collected from the Negro River Basin, Amazon (from January/2002 through January/2004), in both black and white water bodies. Black waters presented the highest HgT, HgORG and HgR concentration (29.1 ng L-1, 1.63 ng L-1 and 3.9 ng L-1, respectively), while, white waters presented the lowest HgT, Hg ORG and HgR concentration (8.8 ng L-1, 0.49 ng L-1 and 1.2 ng L-1, respectively). An inverse correlation between HgT and the water level over the basin was obtained, although the HgORG concentration has increased in the first rainy months and then decreased as the water level rose. Total mercury in surface sediments (0-10 cm) ranged from 70 to 271 mg kg-1 being the methylmercury 0.47-1.79 % of this stock. The results indicate that HgR and the labile dissolved organic matter were introduced into the aquatic environment during the flooding season, especially in the earlier stages, thus contributing to mercury methylation. ©2007 Sociedade Brasileira de Química.

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In low-order streams, the high and variable water flow rates offer both advantages and disadvantages to the life cycle of fishes. Even closely related species living in similar habitats can show differences in life history patterns. Based on oocyte-size distributions, C. lauroi was classified into the fractional spawning type, and C. alipioi into the total spawning type. The absolute fecundity of C. lauroi ranged from 1,313 to 2,925 oocytes; in C. alipioi the absolute fecundity ranged from 2,213 to 25,550 oocytes. The nonparametric Spearman correlation test showed statistical significance between the gonadosomatic index and fecundity for both species. The growth parameters, natural mortality rate and survival rate for females of C. lauroi were: K = 0.68 yr -1, L ∞ = 8.7 cm, t max = 4.4 years, M= 1.62 yr -1, S = 19.79%, and for males: K = 0.78 yr -1, L ∞ = 6.9 cm, t max = 3.8 years, M = 1.89 yr -1, S = 15.11%. The growth parameters, natural mortality rate and survival rate for females of C. alipioi were: K = 0.90 yr -1, L ∞ = 12.2 cm, t max = 3.3 years, M = 1.81 yr -1, S = 16.37%, and for males: K = 0.76 yr -1, L ∞ = 10.1 cm, t max = 3.9 years, M = 1.71 yr -1, S = 18.10%.

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The forest roads construction inevitably causes environmental impacts to adjacent ecosystems and streams. Also the routine activities of roads maintenance may similarly cause environmental impacts of about the same magnitude. The material scraped from the roadway by the motor grader is usually distributed along the roadsides, from where it may easily be washed out toward the streams. Therefore, quantifying the amount of sediments removed during road maintenance activities may provide important information of this stream sedimentation potential. For this purpose, three forest roads were divided in 30 m long segments, marked with leveled stakes. A nylon thread was then stretched across the leveled stakes and the distance from the nylon thread to the road surface was measured before and after the mechanical scraping of the road. The average removal of sediments was of 2,13 cm. Considering the mean density of soil 1,6 g cm -3, the average removal of sediments was of 341 t ha -1 of road. Considering still a 3,9 m wide and 150 m long road as an example, the total amount of removed sediments would be around 19,9 t. Road maintenance, therefore, must be well planned in order to avoid or minimize stream sedimentation.

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The tractor is one of the machines that more traffics over the soil during the processes involving agricultural production. The interaction tractor/soil is made by the tires which, in most of the cases, are pneumatic. The tire type and the tractor travel speed, interfere directly on the pressure over the soil. One of the techniques employed to evaluate the alterations that tractor traffic causes in the soil is to measure its Cone Index. The aim of this research was to evaluate the same Cone Index alterations caused by an agricultural tractor equipped with both radial tires and bias ply tires, trafficking mobilized soil in four different travel speeds. The experiment was performed in a LATOSSOLO VERMELHO, located 22°51' S, 48°25'W and 770 m of altitude, in Botucatu-SP, Brazil. The soil mobilization was performed with a chisel plow and a disc arrow. The traction was accomplished with a John Deere tractor, model 6600, with 88 kW of power and 6,723 kg. Equipment requiring a force of 25kN was traced by the tractor draw bar. The experimental design was in randomized blocks with 4 × 2 factorial arrangements, with two distinct treatments corresponding to the types of tires (bias and radial) and the four travel speeds, with six replications. There were selected the following speeds: 3.5, 3.9, 5.1 and 5.9 km h-1. To determine the soil resistance, there was utilized MSSU - Mobile Soil Sampling Unit, with which the Cone Index was obtained in layers from 0-100, 100-200, 200-300, 300-400, 400-500 and over 500 mm deep. The Cone Index where evaluated in areas with non contact between tire and soil (ICn) and in the tire footprint track (ICp). There were calculated the Cone Index increments caused by the tractor tire (AIC) and the results showed that as the tractor travel speed increased, there were observed decrements in the medium values of cone index. The radial tire provided smaller values of the Cone Index in the superficial layer of the soil (0 to 100 mm) in relation to the bias ply tire, when the speed was approximately 6 km h-1. The increment in the Cone Index, promoted by the tractor, was more intense in the first 200 mm depth, but it also reached the layer from 200 to 300 mm.

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Investigation of the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in chronic myeloid leukemia patients is essential to predict prognosis and survival. In 20 patients treated at the Bone Marrow Transplantation Unit of São José do Rio Preto (São Paulo, Brazil), we used fluorescence in situ hybridization (FISH) to investigate the frequency of cells with BCR/ABL rearrangement at diagnosis and at distinct intervals after allo-HSCT until complete cytogenetic remission (CCR). We investigated the disease-free survival, overall survival in 3 years and transplant-related mortality rates, too. Bone marrow samples were collected at 1, 2, 3, 4, 6, 12, and 24 months after transplantation and additional intervals as necessary. Success rate of the FISH analyses was 100%. CCR was achieved in 75% of the patients, within on average of 3.9 months; 45% patients showed CCR within 60 days after HSCT. After 3 years of the allo-HSCT, overall survival rate was 60%, disease-free survival was 50% and the transplant-related mortality rate was 40%. The study demonstrated that the BCR-ABL FISH assay is useful for follow-up of chronic myeloid leukemia patients after HSCT and that the clinical outcome parameters in our patient cohort were similar to those described for other bone marrow transplantation units. ©FUNPEC-RP.

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This study evaluated the effect of mechanical cycling on the bond strength of zirconia posts to root dentin. Thirty single-rooted human teeth were transversally sectioned to a length of 16 mm. The canal preparation was performed with zirconia post system drills (CosmoPost, Ivoclar) to a depth of 12 mm. For post cementation, the canals were treated with total-etch, 3-steps All-Bond 2 (Bisco), and the posts were cemented with Duolink dual resin cement (Bisco). Three groups were formed (n = 10): G1 - control, no mechanical cycling; G2 - 20,000 mechanical cycles; G3 - 2,000,000 mechanical cycles. A 1.6-mm-thick punch induced loads of 50 N, at a 45° angle to the long axis of the specimens and at a frequency of 8 Hz directly on the posts. To evaluate the bond strengths, the specimens were sectioned perpendicular to the long axis of the teeth, generating 2-mm-thick slices, approximately (5 sections per teeth), which were subjected to the push-out test in a universal testing machine at a 1 mm/min crosshead speed. The push-out bond strength was affected by the mechanical cycling (1-way ANOVA, p = .0001). The results of the control group (7.7 ± 1.3 MPa) were statistically higher than those of G2 (3.9 ± 2.2 MPa) and G3 (3.3 ± 2.3 MPa). It was concluded that the mechanical cycling damaged the bond strength of zirconia posts to root dentin.

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The objective of this study was to evaluate the effect of the physical state of the culture medium on the behavior in vitro of the bromeliaceas Neoregelia cruenta, Tillandsia stricta, Vriesea gigantea, V. guttata e V. incun/ata. Micropropagated shoots had been cultivated in culture medium MS, with 30 g sucrose, 2,5 mg dm-3 BAP, and 0,5 mg dm-3 ANA, establishing the treatments: T1- half-solid with 7 g agar; T2- static liquid; T3- liquid under-agitation of 90 rpm; and T4-static liquid with bridge of paper filter. After 30 days, the use of static way of liquid culture presented better results in relation of proliferative average rate in all the species (9.4 shoots in N. cruenta, 5.6 in T. stricta, 11.5 in V. gigantea, 9.2 in V. guttata and 3.9 in V. incurvata). In relation the average height of the shoots, was distinguished for N. cruenta the liquid under-agitation (2.83 cm), T. stricta and V. incurvata the semisolid (1.76 cm and 2.02 cm, respectively) and V. gigantea and V. guttata the static liquid (0.61 cm and 1.48 cm, respectively). The use of medium MS static liquid was more suitable for in vitro culture of bromeliads species studied.

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Background: Health-related quality of life (HRQOL) measurements provide valuable information about the psychological and social impact of treatment on patients with cystic fibrosis (CF). This study evaluated the HRQOL of Brazilian patients with CF and assessed the changes in HRQOL domains over 1 year after dornase alfa (Pulmozyme) introduction. Patients and Methods: One hundred fifty-six stable patients with CF and 89 caregivers answered the Portuguese-validated version of the Cystic Fibrosis Questionnaire-Revised (CFQ-R) at baseline (T 0), and at 3 (T 1), 6 (T 2), 9 (T 3), and 12 (T 4) months of follow-up. Eighteen patientswere excluded because they did not fulfill the inclusion criteria. The patients were analyzed in two groups: those aged 6-11 years and those aged 14 years and older. ANOVA for observed repeated results and the last observation carried forward (LOCF) method for missing data were used for the statistical analysis. Results: After 1 year of follow-up, there was significant improvement in respiratory symptoms (T 4-T 0=8.1; 95% confidence interval (95% CI)=[2.1;14.0]; effect size (ES)=0.35; P<0.001), Emotional Functioning (T 4-T 0=5.6; 95% CI=[1.1;10.1]; ES=0.31; P<0.05), Social Functioning (T 4-T 0=6.0; 95% CI=[1.3;11.7]; ES=0.31; P<0.05), Body Image (T 4-T 0=11.9; 95% CI=[4.1;19.7]; ES=0.42; P<0.05), and Treatment Burden (T 4-T 0=5.3; 95% CI=[0.3;10.3]; ES=0.24; P<0.05) domains in the younger group. A significant improvement in Role Functioning (T 4-T 0=6.1; 95% CI=[1.1;11.1]; ES=0.40; P<0.05), Body Image (T 4-T 0=12.6; 95% CI=[3.5;21.7]; ES=0.46; P<0.05), and Weight (T 4-T 0=11.7; 95% CI=[1.8;21.6]; ES=0.40; P<0.05) was obtained in the older group. The caregivers' CFQ-R showed improvements in the Digestive Symptoms (T 4-T 0=5.5; 95% CI=[1.5;9.4]; ES=0.30; P<0.05), Respiratory Symptoms (T 4-T 0=7.6; 95% CI=[3.9;11.4]; ES=0.48; P<0.05), and Weight (T 4-T 0=10.1; 95% CI=[1.6;18.6]; ES=0.26; P<0.05) domains. Conclusion: The introduction of dornase alfa improved the HRQL of the patients with CF during the first year of treatment. © 2010 Wiley-Liss, Inc.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Sponge spicules are siliceous microfossils that are especially useful for analysis of sandy fluvio-lacustrine sediments. Sponge spicules in a long sediment core (~550 cm below surface), consisting of fine sand, sandy silt, and organic-rich mud, recovered from the floodplain of the Nabileque River, southern Pantanal, Brazil (S20°16′38. 3″/W57°33′00. 0″), form the basis of a novel paleoenvironmental interpretation for this region. Optically stimulated luminescence dates constrain the timing of deposition to the middle-late Holocene and all spicules identified are typical of the Brazilian cerrado biome. The base of the section is dominated by Oncosclera navicella Carter 1881, Metaniaspinata Carter 1881, and Corvospongilla seckti Bonetto and Ezcurra de Drago 1966, which indicate a lotic to semi-lotic environment strongly influenced by an actively meandering river channel at ~6. 7-5. 7 ka BP. The appearance of Heterorotula fistula Volkmer-Ribeiro and Motta 1995, Dosilia pydanieli Volkmer-Ribeiro 1992 and Radiospongilla amazonensis Volkmer-Ribeiro and Maciel 1983 at ~340 cm downcore suggests a reduction in flowing water and a more stable lentic environment, consistent with deposition in an oxbow lake. This oxbow lake environment existed during an interval of regional aridity between ~4. 5 and 3. 9 ka BP. Spicules, as well as phytoliths and diatoms, are highly variable moving up-section, with species from both lotic and lentic ecosystems present. Above ~193 cm, the total abundance of spicules declines, consistent with wetter climate conditions and development of an underfit river similar to the modern floodplain. Results support hypotheses related to migration of the Paraguay River inferred from geomorphological studies and add a key southern-region dataset to the emerging Holocene database of paleoenvironmental records from the Pantanal wetlands. © 2012 Springer Science+Business Media Dordrecht.

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Objectives: The aim of this study was to compare the long-term clinical effects produced by subepithelial connective tissue graft (SCTG) and guided tissue regeneration combined with demineralized freeze-dried bone allograft (GTR-DFDBA) in the treatment of gingival recessions in a 30-month follow-up clinical trial. Methods: Twenty-four defects were treated in 12 patients who presented canine or pre-molar Miller class I and/or II bilateral gingival recessions. GTR-DFDBA and SCTG treatments were performed in a randomized selection in a split-mouth design. The clinical measurements included root coverage (RC), gingival recession (GR), probing depth (PD), clinical attachment level (CAL) and keratinized tissue width (KTW). These clinical parameters were evaluated at baseline and after 6, 18 and 30 months post-surgery. Results: The changes in RC, GR, PD and CAL did not show significant differences between groups (p > 0.05). Both procedures promoted similar RC (GTR-DFDBA: 87% and SCTG: 95.5%) and similar reduction in GR (GTR-DFDBA: 3.25 mm and SCTG: 3.9 mm), PD (GTR-DFDBA: 1.6 mm and SCTG: 1.2 mm) and CAL (GTR-DFDBA: 4.9 mm and SCTG: 5.0 mm). The increase in KTW was significantly higher (p = 0.02) in the SCTG group (3.5 mm) than in the GTR-DFDBA group (2.4 mm). Conclusions: Both techniques for treatment of gingival recession (SCTG and GTR-DFDBA) lead to favourable and long-term stable results, but SCTG promoted a more favourable increase in keratinized tissue. © 2012 Elsevier Ltd. All rights reserved.

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Objectives: To evaluate the effects of surface treatment, surface hydration (SH) and application method (AM) on the tensile bond strength of the Silorane Adhesive System (SAS) to dentine. Methods: Ninety bovine teeth were used. For the control group (n = 10), each dentine surface was treated according to the manufacturer's instructions of the SAS. The remaining teeth were randomly distributed into two groups (n = 40), according to the type of dentine surface treatment (ST) - 37% phosphoric acid or Er:YAG Laser prior to the application of the SAS. Each group was further divided into 2 subgroups (n = 20), according to the SH status: dry (D) or wet (W). Each subgroup was further divided into 2 subgroups (n = 10), according to the application method [AM: Active (AC) mode or Passive (PA) mode]. A coat of resin composite (Filtek P90) was applied on the surface. Artificial ageing was performed with a thermo-mechanical cycling machine. The specimens were sectioned into 1 mm × 1 mm × 10 mm sticks and stressed to failure using a universal testing machine. The remaining teeth in each group were used for Scanning Electron Microscopy to examine the fractured area. Data were subjected to a three-way ANOVA, Tukey's test and Dunnet's test (α = 0.05). Results: The ANOVA showed significant differences for SH and AM, but not for ST. For SH, the results of Tukey's test were (in MPa): D-14.9(±3.8)a, W-17.1(±4.3)b; and for AM: PA-14. 9(±4.2)a, AC-17.1(±3.9) b. Conclusions: Acid etching, when combined with a moist dentine surface and the use of primer agitation, improves the bond strength of the SAS to dentine. Clinical Significance: According to the results of the present in vitro study, modification of the application protocols for the silorane-based adhesive system may improve its clinical performance. © 2012 Published by Elsevier Ltd.

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This study examined the effects of long-term creatine supplementation combined with resistance training (RT) on the one-repetition maximum (1RM) strength, motor functional performance (e.g., 30-s chair stand, arm curl, and getting up from lying on the floor tests) and body composition (e.g., fat-free mass, muscle mass, and % body fat using DEXA scans) in older women. Eighteen healthy women (64.9 ± 5.0 years) were randomly assigned in a double-blind fashion to either a creatine (CR, N = 9) or placebo (PL, N = 9) group. Both groups underwent a 12-week RT program (3 days week-1), consuming an equivalent amount of either creatine (5.0 g day-1) or placebo (maltodextrin). After 12 week, the CR group experienced a greater (P < 0.05) increase (Δ%) in training volume (+164.2), and 1RM bench press (+5.1), knee extension (+3.9) and biceps curl (+8.8) performance than the PL group. Furthermore, CR group gained significantly more fat-free mass (+3.2) and muscle mass (+2.8) and were more efficient in performing submaximal-strength functional tests than the PL group. No changes (P > 0.05) in body mass or % body fat were observed from pre- to post-test in either group. These results indicate that long-term creatine supplementation combined with RT improves the ability to perform submaximal-strength functional tasks and promotes a greater increase in maximal strength, fat-free mass and muscle mass in older women. © 2012 Springer-Verlag Berlin Heidelberg.

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The top-quark pair production cross section in 7 TeV center-of-mass energy proton-proton collisions is measured using data collected by the CMS detector at the LHC. The measurement uses events with one jet identified as a hadronically decaying τ lepton and at least four additional energetic jets, at least one of which is identified as coming from a b quark. The analyzed data sample corresponds to an integrated luminosity of 3.9 fb-1 recorded by a dedicated multijet plus hadronically decaying τ trigger. A neural network has been developed to separate the top-quark pairs from the W+jets and multijet backgrounds. The measured value of σtt̄= 152 ± 12,(stat.) ± 32,(syst.) ±,(lum.) pb is consistent with the standard model predictions. © 2013 CERN for the benefit of the CMS collaboration.

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Objectives: To evaluate the influence on osseointegration of Deproteinized bovine bone mineral (DBBM) particles used to fill defects of at least 1 mm around implants having no primary contact with bone. Material and methods: Premolars and first molars were extracted bilaterally from the mandible of six Labrador dogs. After 3 months of healing, mucoperiosteal full-thickness flaps were elevated, and one recipient site was prepared in the molar region of each hemi-mandible to place implants. These were installed with a deliberate circumferential and periapical space to the bone walls of 1.2 mm. All implants were stabilized with passive fixation plates to maintain the implants in situ and without any contact with the implant bed. The control sites were left to be filled with coagulum, while at the test sites, the residual gap was filled with DBBM. After 3 months of submerged healing, the animals were sacrificed. Ground sections were prepared and analyzed histomorphometrically. Results: Mineralized bone-to-implant contact was 4.0% and 3.9% for control and test sites, respectively. The width of the residual defects was 0.48 mm and 0.88 mm at the control and test sites, respectively. The percentage of implant surface covered by a layer of dense connective tissue of 0.12 mm of width on average was 84.9% and 88.5% at the control and test sites, respectively. Conclusion: A minor and not predictable degree of contact or distance osteogenesis was obtained on the implant surface when primary contact of the implant surface with the implant bed had deliberately been avoided. DBBM grafting of the artificial gap did not favor osseointegration. Neither did it enhance the ability to bridge the gap with newly formed bone in an artificial defect wider than 1 mm. © 2013 John Wiley & Sons A/S.