Optimisation of environmental gas cleaning routes for solid wastes cogeneration systems - Part I - Analysis of waste incineration steam cycle

Research of advanced technologies for energy generation contemplates a series of alternatives that are introduced both in the investigation of new energy sources and in the improvement and/or development of new components and systems. Even though significant reductions are observed in the amount of emissions, the proposed alternatives require the use of exhaust gases cleaning systems. The results of environmental analyses based on two configurations proposed for urban waste incineration are presented in this paper; the annexation of integer (Boolean) variables to the environomic model makes it possible to define the best gas cleaning routes based on exergetic cost minimisation criteria. In this first part, the results for steam cogeneration system analysis associated with the incineration of municipal solid wastes (MSW) is presented. (c) 2007 Elsevier Ltd. All rights reserved.

An air-standard cycle and a thermodynamic perspective on operational limits of Ranque-Hilsh or vortex tubes

A Thermodynamic air-standard cycle was envisaged for Ranque-Hilsh (R-H) or Vortex Tubes to provide relevant Thermodynamic analysis and tools for setting operating limits according to the conservation laws of mass and energy, as well as the constraint of the Second Law of Thermodynamics. The study used an integral or control volume approach and resulted in establishing working equations for evaluating the performance of an R-H tube. The work proved that the coefficient of performance does not depend on the R-H tube operating mode, i.e., the same value is obtained independently if the R-H tube operates either as a heat pump or as a refrigeration device. It was also shown that the isentropic coefficient of performance displays optima values of cold and hot mass fractions for a given operating pressure ratio. Finally, the study was concluded by comparing the present analysis with some experimental data available in the literature for operating pressures ranging 2-11 atm. (C) 2010 Elsevier Ltd and IIR. All rights reserved.

Phase I trial of DNA-hsp65 immunotherapy for advanced squamous cell carcinoma of the head and neck

Considering that mycobacterial heat-shock protein 65 (hsp65) gene transfer can elicit a profound antitumoral effect, this study aimed to establish the safety, maximum-tolerated dose (MTD) and preliminary efficacy of DNA-hsp65 immunotherapy in patients with advanced head and neck squamous cell carcinoma (HNSCC). For this purpose, 21 patients with unresectable and recurrent HNSCC were studied. Each patient received three ultrasound-guided injections at 21-day intervals of: 150, 600 or 400 mu g of DNA-hsp65. Toxicity was graded according to CTCAE directions. Tumor volume was measured before and after treatment using computed tomography scan. The evaluation included tumor mass variation, delayed-type hypersensitivity response and spontaneous peripheral blood mononuclear cell proliferation before and after treatment. The MTD was 400 mg per dose. DNA-hsp65 immunotherapy was well tolerated with moderate pain, edema and infections as the most frequent adverse effects. None of the patients showed clinical or laboratory alterations compatible with autoimmune reactions. Partial response was observed in 4 out of 14 patients who completed treatment, 2 of which are still alive more than 3 years after the completion of the trial. Therefore, DNA-hsp65 immunotherapy is a feasible and safe approach at the dose of 400 mg per injection in patients with HNSCC refractory to standard treatment. Further studies in a larger number of patients are needed to confirm the efficacy of this novel strategy.

Ratio of weight to height gain: a useful tool for identifying children at risk of becoming overweight or obese at preschool age

PURPOSE: To analyze the usefulness of the weight gain/height gain ratio from birth to two and three years of age as a predictive risk indicator of excess weight at preschool age. METHODS: The weight and height/length of 409 preschool children at daycare centers were measured according to internationally recommended rules. The weight values and body mass indices of the children were transformed into a z-score per the standard method described by the World Health Organization. The Pearson correlation coefficients (rP) and the linear regressions between the anthropometric parameters and the body mass index z-scores of preschool children were statistically analyzed (alpha = 0.05). RESULTS: The mean age of the study population was 3.2 years (± 0.3 years). The prevalence of excess weight was 28.8%, and the prevalence of overweight and obesity was 8.8%. The correlation coefficients between the body mass index z-scores of the preschool children and the birth weights or body mass indices at birth were low (0.09 and 0.10, respectively). There was a high correlation coefficient (rP = 0.79) between the mean monthly gain of weight and the body mass index z-score of preschool children. A higher coefficient (rP = 0.93) was observed between the ratio of the mean weight gain per height gain (g/cm) and the preschool children body mass index z-score. The coefficients and their differences were statistically significant. CONCLUSION: Regardless of weight or length at birth, the mean ratio between the weight gain per g/cm of height growth from birth presented a strong correlation with the body mass index of preschool children. These results suggest that this ratio may be a good indicator of the risk of excess weight and obesity in preschool-aged children.

Discharge-calcium concentration relationships in streams of the Amazon and Cerrado of Brazil: soil or land use controlled

Stream discharge-concentration relationships are indicators of terrestrial ecosystem function. Throughout the Amazon and Cerrado regions of Brazil rapid changes in land use and land cover may be altering these hydrochemical relationships. The current analysis focuses on factors controlling the discharge-calcium (Ca) concentration relationship since previous research in these regions has demonstrated both positive and negative slopes in linear log(10)discharge-log(10)Ca concentration regressions. The objective of the current study was to evaluate factors controlling stream discharge-Ca concentration relationships including year, season, stream order, vegetation cover, land use, and soil classification. It was hypothesized that land use and soil class are the most critical attributes controlling discharge-Ca concentration relationships. A multilevel, linear regression approach was utilized with data from 28 streams throughout Brazil. These streams come from three distinct regions and varied broadly in watershed size (< 1 to > 10(6) ha) and discharge (10(-5.7)-10(3.2) m(3) s(-1)). Linear regressions of log(10)Ca versus log(10)discharge in 13 streams have a preponderance of negative slopes with only two streams having significant positive slopes. An ANOVA decomposition suggests the effect of discharge on Ca concentration is large but variable. Vegetation cover, which incorporates aspects of land use, explains the largest proportion of the variance in the effect of discharge on Ca followed by season and year. In contrast, stream order, land use, and soil class explain most of the variation in stream Ca concentration. In the current data set, soil class, which is related to lithology, has an important effect on Ca concentration but land use, likely through its effect on runoff concentration and hydrology, has a greater effect on discharge-concentration relationships.

Differences in both matrix metalloproteinase 9 concentration and zymographic profile between plasma and serum with clot activators are due to the presence of amorphous silica or silicate salts in blood collection devices

Matrix metalloproteinases (MMPs) are promising diagnostic tools, and blood sampling/handling alters MMP concentrations between plasma and serum and between serum with and without clot activators. To explain the higher MMP-9 expression in serum collected with clot accelerators relative to serum with no additives and to plasma, we analyzed the effects of increasing amounts of silica and silicates (components of clot activators) in,citrate plasma, serum, and huffy coats collected in both plastic and glass tubes from 50 healthy donors, and we analyzed the effects of silica and silicate on cultured leukemia cells. The levels of MMP-2 did not show significant changes between glass and plastic tubes, between serum and plasma, between serum with and without clot accelerators, or between silica and silicate treatments. No modification of MMP-9 expression was obtained by the addition of silica or silicate to previously separated plasma and serum. Increasing the amounts of nonsoluble silica and soluble silicate added to citrate and empty tubes prior to blood collection resulted in increasing levels of MMP-9 relative to citrate plasma and serum. Silica and silicate added to buffy coats and leukemia cells significantly induced MMP-9 release/secretion, demonstrating that both silica and silicate induce the release of pro- and complexed MMP-9 forms. We recommend limiting the misuse of serum and avoiding the interfering effects of clot activators. (c) 2007 Elsevier Inc. All rights reserved.

Stimulation of 5-HT1A or 5-HT2A receptors in the ventrolateral periaqueductal gray causes anxiolytic-, but not panicolytic-like effect in rats

Evidences from studies using electrical or chemical stimulation of the midbrain periaqueductal gray (PAG) suggest that whereas the dorsal PAG is critical for the regulation of panic-related defensive behaviors, the ventrolateral PAG (vlPAG) modulates generalized anxiety-related responses. In the present study we evaluated whether the activation of 5-HT1A and 5-HT2A/2C receptors in the ventrolateral column of the periaqueductal gray (vlPAG) causes differential effects on an anxiety- and a panic-related defensive behavior, respectively, inhibitory avoidance and escape, in male Wistar rats submitted to the elevated T-maze. Our results showed that intra-vlPAG injection of the endogenous agonist serotonin, the 5-HT1A/7 agonist 8-OH-DPAT or 5-HT2A/2C agonist DOI impaired the acquisition of inhibitory avoidance, without interfering with escape performance. The same selective anxiolytic effect was also observed after local administration of the benzodiazepine receptor agonist midazolam. Moreover, as shown by the results of antagonism studies, 5-HT2A receptors are recruited for the anxiolysis caused by serotonin and DOI. while 5-HT1A receptors account for the effect of 8-OH-DPAT. In conclusion, our data show that the activation of 5-HT1A and 5-HT2A receptors in the vlPAG affects defensive responses related to generalized anxiety, but not panic disorder. (C) 2008 Elsevier B.V. All rights reserved.

Effects of Erosive, Cariogenic or Combined Erosive/Cariogenic Challenges on Human Enamel An in situ/ex vivo Study

Individuals with cariogenic diet can also consume erosive beverages. Thus, it seems necessary to investigate a possible caries/erosion interaction. To test in situ/ex vivo a combination of these challenges, 11 subjects wore intraoral appliances containing four enamel blocks randomly assigned. In the first 2-week phase, the appliances were immersed in a cola drink 3 times/day. Two blocks were free of plaque (erosion only: EO) and two blocks were covered with plaque (erosion + plaque: EP). In the second 2-week phase, four new blocks were all covered with plaque and subjected to a sucrose solution 8 times/day. Among the four new blocks, two were also subjected to the cola drink 3 times/day (erosion + caries: EC) while the other two were not (caries only: CO). Thus, in EO, the specimens were fixed at the intraoral appliance level. In EP, EC and CO they were fixed 1.0 mm under the appliance level and covered with plastic meshes for dental plaque accumulation. Changes in wear and hardness were measured. Data were tested using ANOVA and Tukey`s test (p < 0.05). Mean values of wear (mu m) and change in hardness (kp/mm(2)) were: EO 4.82/310; EP 0.14/48; EC 0.34/245; CO 0.42/309. With respect to surface softening, EP and EC differed significantly from each other and from EO and CO, which did not differ significantly. EO presented significantly higher wear than the other groups. The data suggest that the presence of dental plaque can decrease the acid attack of an erosive drink and the association of erosive and cariogenic challenges showed less enamel alterations when compared to erosive or cariogenic challenges only. Copyright (C) 2008 S. Karger AG, Basel

Comparison of GPX with or without solvent and hand files in removing filling materials from root canals-An ex vivo study

Objective. The aim of this study was to compare GPX instruments and hand files for gutta-percha removal. Study design. Fifty maxillary central incisors with a single straight canal were instrumented and filled. The teeth were divided into 5 groups of 10 specimens each, according to the gutta-percha removal techniques: group 1: GPX (21-mm-long teeth); group 2: GPX and xylol as solvent (21-mm-long teeth); group 3: GPX (25-mm-long teeth); group 4: GPX and xylol as solvent (25-mm-long teeth); and group 5: hand files and xylol as solvent. The amount of time for gutta-percha removal and the number of fractured instruments were evaluated. Radiographs were taken, and the teeth were grooved longitudinally and split. The area of residual debris was measured using Sigma Scan software. Results. The time for filling material removal was significantly shorter when GPX was used (P < .05). Overall, hand files and solvent produced fewer remnants of filling materials (P < .05). In the GPX 25 mm-long teeth group, the filling material was not removed in the apical third. Conclusions. Under the experimental conditions, the GPX instruments proved to be faster than hand instruments in removing root filling materials; however, hand instruments left a smaller amount of residual filling materials on the canal walls. The GPX instruments did not pull the gutta-percha beyond its tip. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 110: 675-680)

Evaluation of the presence or absence of papilla between tooth and implant

Objective: The purpose of this study was to evaluate the papilla level adjacent to single-tooth implants in the maxillary anterior region in individuals with cleft lip, alveolus, and palate to verify whether there is correlation among the vertical distance, horizontal distance, dental/prosthetic crown shape, and periodontal/peri-implant biotype with the presence of interproximal papilla. Design: Cross-sectional. Setting: Hospital for Rehabilitation of Craniofacial Anomalies, University of Sao Paulo (HRAC/USP). Patients: 77 papillae in 40 patients. Interventions: The periodontal/peri-implant biotype was clinically evaluated and characterized as thin or thick. Intraoral photographs were used to evaluate the presence or absence of papilla. Main Outcome Measures: Classification in scores (0 to 3) and determination of length (CL) and width (CW) of crowns adjacent to papillae. The CW/CL ratio was calculated for each crown in order to characterize it as square-shaped or triangular-shaped. The vertical and horizontal distances were obtained by radiographic evaluation. Results: The correlations between vertical distance and papilla score and horizontal distance and papilla score were statistically significant (p= .02 and p = .01). There was no significant difference between crown shape and periodontal/peri-implant biotype in distinct correlations with the papilla score (p = .41 and p = .07). Conclusion: The results suggest that the vertical and horizontal distances may have independent or combined relationship with the existence of interproximal papilla; the periodontal/peri-implant biotype (phenotype) was not correlated with the presence or absence of papilla, as well as the shape of the dental/prosthetic crown.

Bleaching Agents with Varying Concentrations of Carbamide and/or Hydrogen Peroxides: Effect on Dental Microhardness and Roughness

To evaluate the effect of low and highly concentrated bleaching agents on microhardness and surface roughness of bovine enamel and root dentin. According to a randomized complete block design, 100 specimens of each substrate were assigned into five groups to be treated with bleaching agents containing carbamide peroxide (CP) at 10% (CP10); hydrogen peroxide (HP) at 7.5% (HP7.5) or 38% (HP38), or the combination of 18% of HP and 22% of CP (HP18/CP22), for 3 weeks. The control group was left untreated. Specimens were immersed in artificial saliva between bleaching treatments. Knoop surface microhardness (SMH) and average surface roughness (Ra) were measured at baseline and post-bleaching conditions. For enamel, there were differences between bleaching treatments for both SMH and Ra measurements (p = 0.4009 and p = 0.7650, respectively). SMH significantly increased (p < 0.0001), whereas Ra decreased (p = 0.0207) from baseline to post-bleaching condition. For root dentin, the group treated with CP10 exhibited the significantly highest SMH value differing from those groups bleached with HP18/CP22, HP7.5, which did not differ from each other. Application of HP38 resulted in intermediate SMH values. No significant differences were found for Ra (p = 0.5975). Comparing the baseline and post-bleaching conditions, a decrease was observed in SMH (p < 0.0001) and an increase in Ra (p = 0.0063). Bleaching agents with varying concentrations of CP and/or HP are capable of causing mineral loss in root dentin. Enamel does not perform in such bleaching agent-dependent fashion when one considers either hardness or surface roughness evaluations. Bleaching did not alter the enamel microhardness and surface roughness, but in root dentin, microhardness seems to be dependent on the bleaching agent used.

Biodegradable Films Based on Blends of Gelatin and Poly (Vinyl Alcohol): Effect of PVA Type or Concentration on Some Physical Properties of Films

The aim of this work was to develop biodegradable films based on blends of gelatin and poly (vinyl alcohol) (PVA), without a plasticizer. Firstly, the effect of five types of PVA with different degree of hydrolysis (DH) on the physical properties of films elaborated with blends containing 23.1% PVA was studied. One PVA type was then chosen for the study of the effect of the PVA concentration on the mechanical properties, color, opacity, gloss, and water solubility of the films. The five types of PVA studied allowed for films with different characteristics, but with no direct relationship with the DH of the PVA. Therefore, the PVA Celvol (R) 418 with a DH = 91.8% was chosen for the second part, because they produced films with greater tensile strength. The PVA concentration affected all studied properties of films. These results could be explained by the results of the DSC and FTIR analyses, which showed that some interactions between the gelatin and the PVA occurred depending on the PVA concentration, affecting the crystallinity of the films.

Hydrodynamical simulations of Galactic fountains - I. Evolution of single fountains

The ejection of the gas out of the disc in late-type galaxies is related to star formation and is due mainly to Type II supernovae. In this paper, we studied in detail the development of the Galactic fountains in order to understand their dynamical evolution and their influence on the redistribution of the freshly delivered metals over the disc. To this aim, we performed a number of 3D hydrodynamical radiative cooling simulations of the gas in the Milky Way where the whole Galaxy structure, the Galactic differential rotation and the supernova explosions generated by a single OB association are considered. A typical fountain powered by 100 Type II supernovae may eject material up to similar to 2 kpc which than collapses back mostly in the form of dense, cold clouds and filaments. The majority of the gas lifted up by the fountains falls back on the disc remaining within a radial distance Delta R = 0.5 kpc from the place where the fountain originated. This localized circulation of disc gas does not influence the radial chemical gradients on large scale, as required by the chemical models of the Milky Way which reproduce the metallicity distribution without invoking large fluxes of metals. Simulations of multiple fountains fuelled by Type II supernovae of different OB associations will be presented in a companion paper.

Mandibulofacial Dysostosis, Severe Lower Eyelid Coloboma, Cleft Palate, and Alopecia: A New Distinct Form of Mandibulofacial Dysostosis or a Severe Form of Johnson-McMillin Syndrome?

We describe a patient with a phenotype characterized by mandibulofacial dysostosis with severe lower eyelid coloboma, cleft palate, abnormal ears, alopecia, delayed eruption and crowded teeth, and sensorioneural hearing loss. The karyotype and the screening for mutations in the coding region of TCOF1 gene were normal. The clinical signs of our case overlap the new mandibulofacial dysostosis described by Stevenson et al. [2007] and the case with Johnson-McMillin syndrome described by Cushman et al. [2005]. The similar clinical signs, mainly, the severe facial involvement observed in these cases suggest that they can represent a new distinct form of mandibulofacial dysostosis or the end of the spectrum of Johnson McMillin syndrome. (C) 2010 Wiley-Liss, Inc.

Existence of secondary bifurcations or isolas for PDEs

In this paper, we introduce a method to conclude about the existence of secondary bifurcations or isolas of steady state solutions for parameter dependent nonlinear partial differential equations. The technique combines the Global Bifurcation Theorem, knowledge about the non-existence of nontrivial steady state solutions at the zero parameter value and explicit information about the coexistence of multiple nontrivial steady states at a positive parameter value. We apply the method to the two-dimensional Swift-Hohenberg equation. (C) 2011 Elsevier Ltd. All rights reserved.