Avaliação da distribuição da densidade em MDF a partir da técnica da onda de ultra-som

The goal of this research was to determine the density distribution in medium density fiberboard (MDF), manufactured with polyurethane derived from castor oil using, ultrasonic wave technique. The equipment used in this test is Steinkamp BP7 with plan and exponential transducers, both with 45 kHz frequencies, located in several zones on the plate in order to determine wave ultrasonic velocity. The Pinus caribaea and Eucalyptus grandis fiberboard were manufactured in the quality control and products development laboratory of Duratex with 500 mm long, 500 mm large, 8 and 15 mm of thickness. Three MDF for each fiber specimen and thickness were fabricated, totalizing twelve plates tested. The MDF were produced with 5% polyurethane addition, in temperature of 160°C, tension press of 53 bars and addition of moisture content of 12%. For determination of fiberboard density, samples were extracted from the same zones where the wave ultrasonic velocity was determined. In this case, DAX-Ray equipment was used. Statistical analysis shows good agreement with wave ultrasonic velocity and the density profile, validating the application of non-destructive technique in order to determine the density profile of MDF's.

Internal adaptation of cast titanium crowns

As the adaptation of titanium crowns obtained by Rematitan Plus investment, specific for titanium, is not recognized to be suitable, this study evaluated the effect of the concentration of the specific liquid and the temperature of the mold of investments on the internal misfit of crowns cast on commercially pure titanium. Individual dies of epoxy resin were obtained, representing teeth prepared for full-crown restoration with a 6-degree axial surface convergence angle and shoulder (1.0 mm). For the waxing of each crown, a ring-shaped stainless steel matrix (8.0mm internal diameter; 7.5 mm height) was adapted above the individual dies of epoxy resin. The Rematian Plus investment was mixed according to the manufacturer's instructions using two different concentrations of the specific liquid: 100%, 75%. Casting was performed in a Discovery Plasma Ar-arc vacuum-pressure casting machine with molds at temperatures of 430°C, 515°C and 600°C. The crowns were cleaned individually in a solution (1% HF + 13% HNO3) for 10 min using a ultrasonic cleaner, with no internal adaptations, and luted with zinc phosphate cement under a 5 kg static load. The crown and die assemblies were embedded in resin and sectioned longitudinally. The area occupied by cement was observed using stereoscopic lens (10X) and measured by the Leica Qwin image analysis system (mm2). The data for each experimental condition (n=8) were analyzed by Kruskal-Wallis non-parametric test (á=0.05). The results showed that liquid dilution and the increase in mold temperature did not significantly influence the levels of internal fit of the cast titanium crowns. The lowest means (±SD) of internal misfit were obtained for the 430°C/100%: (7.25 mm2 ±1.59) and 600°C/100% (8.8 mm2 ±2.25) groups, which presented statistically similar levels of internal misfit.

Electromyographic analysis of the arm muscles in back support exercises

This study aims at quantifying through electromyography the actions of the biceps brachii-BB (long head), tríceps brachii- TB (long head) and deltoideus-DA (clavicular portion) muscles, during the going (G) and return (R) phases in back support exercises. Surface electrodes were placed at the muscles, according to DELAGI (1981). It was used a specific software and a AID plate to take the signals. After being collected, the records were processed resulting in efficient values (RMS), were normalized by maximum isometric contraction (MVIC=100%) and statistically analysed using the Friedman, DSM and Wilcox non-parametric tests. All the muscles presented electromyographic activity of the movements. The triceps brachii was the muscle with higher activity in both phases of the movement. It was concluded that the exercise is indicated for the arm muscle strength development.

Measuring the efficiency of outsourcing: An illustrative case study from the aerospace industry

Outsourcing is related to the action which an organization deals with its suppliers through a kind of business contract where a specific activity or service has been hired to be made. The outsourcing of some activities has become a common practice in the industry, nowadays. It reduces costs, significantly, in the production process and, at the same time, adds some values to the business organization. However it is necessary to measure the performance of these activities. Data Envelopment Analysis (DEA) is a non-parametric method useful to measure comparative performance. It has a wide range of applications measuring comparative efficiency. The Analytic Hierarchy Process (AHP) is a multiple criteria decision-making method that uses hierarchic structures to represent a decision problem and then develops priorities for the alternatives based on the decision-maker's judgments. This paper presents an integrated application based on DEA and AHP to evaluate the efficiency of subcontracted companies in a Brazilian aerospace factory. © 2007 Springer-Verlag London Limited.

SEM analysis of the in situ early bacterial colonization on two novel feldspathic ceramics submitted to different types of glazing

Aim: The aim of this study was to evaluate in situ, the early bacterial colonization on feldspar-ceramics submitted to different glazing. Methods and Materials: Fourteen standardized disc specimens (diameter: 5 mm, thickness: 1.5 mm) of each of two micro-particulate feldspathic ceramics (VM7 and VM13, Vita) were produced according to manufacturers' specifications for a total of 28 specimens (24 for the analysis of biofilm and 4 for topographic analysis analyzing the ceramic surfaces). Specimens from each type of ceramic were submitted to two different glazing methods composing four groups: VM7 glazed using glazing liquid Vita Akzent® 25 (G1) and glaze firing (G2), VM13 glazed using glazing liquid (G3) and glaze firing (G4). Six individuals (n=6) wore oral appliances with four ceramic specimens, fixed on the buccal face of the appliances. After 8 hours, each sample was evaluated for the presence (1) or absence (0) of bacterial colonization under a scanning electron microscope (SEM) on five randomly selected fields. The value for each sample was cumulative of the results observed in the fields. One sample from each group was evaluated under a SEM to verify the topographic pattern. Results: There was no difference with regard to bacterial colonization between the feldspar-ceramics and between the glazing types (Kruskal-Wallis non-parametric test). Conclusion: Feldspar-ceramics submitted to firing or glaze firing with Vita Akzent® 25 present a similar condition for in situ bacterial colonization. The similar topographic pattern of the ceramic surfaces seems to have influenced the bacterial colonization.

Amifostine reduces the seminiferous epithelium damage in doxorubicin-treated prepubertal rats without improving the fertility status

Background: Amifostine is an efficient cytoprotector against toxicity caused by some chemotherapeutic drugs. Doxorubicin, a potent anticancer anthracycline, is known to produce spermatogenic damage even in low doses. Although some studies have suggested that amifostine does not confer protection to doxorubicin-induced testicular damage, schedules and age of treatment have different approach depending on the protocol. Thus, we proposed to investigate the potential cytoprotective action of amifostine against the damage provoked by doxorubicin to prepubertal rat testes (30-day-old) by assessing some macro and microscopic morphometric parameters 15, 30 and 60 days after the treatment; for fertility evaluation, quantitative analyses of sperm parameters and reproductive competence in the adult phase were also carried out.Methods: Thirty-day-old male rats were distributed into four groups: Doxorubicin (5 mg/kg), Amifostine (400 mg/kg), Amifostine/Doxorubicin (amifostine 15 minutes before doxorubicin) and Sham Control (0.9% saline solution). Standard One Way Anova parametric and Anova on Ranks non-parametric tests were applied according to the behavior of the obtained data; significant differences were considered when p < 0.05.Results: The rats killed 30 and 60 days after doxorubicin treatment showed diminution of seminiferous epithelium height and reduction on the frequency of tubular sections containing at least one type of differentiated spermatogonia; reduction of sperm concentration and motility and an increase of sperm anomalous forms where observed in doxorubicin-treated animals. All these parameters were improved in the Amifostine/Doxorubicin group only when compared to Doxorubicin group. Such reduction, however, still remained below the values obtained from the Sham Control group. Nevertheless, the reproductive competence of doxorubicin-treated rats was not improved by amifostine pre-administration.Conclusions: These results suggest that amifostine promotes a significant reduction of the doxorubicin long-term side effects on the seminiferous epithelium of prepubertal rats, which is reflected in the epidydimal fluid parameters in the adult phase. However, fertility status results suggest that such protection may not be effective against sperm DNA content damage. Further investigation of sperm DNA integrity must be carried out using amifostine and doxorubicin-treated experimental models. © 2010 Vendramini et al; licensee BioMed Central Ltd.

The use of surface electromyography for the study of auricular acupuncture

The advancement of knowledge in neurophysiology has demonstrated that acupuncture is a method of peripheral neural stimulation that promotes local and systemic reflexive responses. The purpose of this study was to determine if surface electromyography can be used as a tool to study the action of auricular acupuncture on striated skeletal muscle. The electromyographic amplitudes of the anterior, middle and posterior deltoid muscle and the upper trapezium muscle with 20%, 40% and 60% of maximal voluntary contraction of 15 healthy volunteers, were analyzed after the individuals were submitted to the auricular acupuncture treatment. The non-parametric Friedman test was used to compare Root Mean Square values estimated by using a 200 ms moving window. Significant results were further analyzed using the Wilcoxon signed rank test. In this exploratory study, the level of significance of each comparison was set to p < 0.05. It was concluded in this study that a surface electromyography can be used as a tool to investigate possible alterations of electrical activity in muscles after auricular acupuncture. However there is still a lack of adequate methodology for its use in this type of study, being that the method used to record the electromyographic signal can also influence the results. © 2008 Elsevier Ltd. All rights reserved.

The influence of grain size coating and shaft angulation of different diamond tips on dental cutting

Objectives: To evaluate the influence of the grain size coating and shaft angulation of ultrasonic and high-speed diamond burs on the dental cutting effectiveness. Materials and Methods: For the grain size evaluation, cavities were prepared on 40 incisors using high-speed (1092 and 1093F KG Sorensen®) and ultrasonic tips (8.2142 and 6.2142-CVDentus®). For the shaft angulation evaluation, cavities were prepared on 40 incisors using uniangulated (T1-CVDentus®) and biangulated (T1-A CVDentus®) ultrasonic tips. The cavities were bisected and examined at 50 magnification. The width and depth of cavities were measured by Leica QWin software. Kruskal-Wallis non-parametric test was used for analysis. Results: The grain size did not affect the cutting effectiveness, but the high-speed burs promoted deeper and wider cavities than the ultrasonic tips. The shaft angulation did not affect the cutting effectiveness; both the angulated and biangulated tips had greater cutting efficiency in dentin than in enamel. Conclusions: Ultrasonic tips promoted more conservative preparations and seemed promising for cavity preparation.

The influence of the flexibility of the chair seat on pressure peak and distribution of the contact area in individuals with cerebral palsy during the execution of a task

This study aimed to determine the influence of flexibility of the chair seat surface on the pressure peak and on the contact area during the execution of a task of handling an object on the seated position by individuals with spastic cerebral palsy. Ten individuals of both genders with diagnosis of spastic cerebral palsy, who had some control to voluntarily move the body and the upper limbs, participated in this study. Quantification of data was carried out in two experimental situations: (1) execution of a task of fitting with upper limbs, and with the individual placed on an adapted canvas seat; (2) execution of a task of fitting with the participant positioned on an adapted wooden seat. Data obtained were submitted to a non-parametric and descriptive statistical analysis using the Wilcoxon test. Results indicated that the use of canvas seat increased the contact area and decreased the pressure peak and the medio-lateral displacement of centre pressure on the seated posture. © 2011 Informa UK, Ltd.

Entrenamiento continuo vs. interválico corriendo en piscina profunda: Efectos sobre la salud de las mujeres obesas

Objectives. To search intermittent and continous trainning (IT and CT, respectively) effects through deep water running for the control and prevention of excessive body fat accumulation and improvement of quality of life. Methods. Experimental study composed by 30 women, aged between 34 to 58 years old, during 12 weeks, three sessions per week, 47 minutes each. Body composition, cardiorespiratory condition and Quality of Life by WHOQOL-Brief were considered. Student's and Wilcoxon's non parametric tests were applied at 5% significance level. Results. With the only exception for social domain of quality of life, all investigated variables revealed improvement in both groups for IT in comparison to CT. Conclusion. Deep water running contributes to body fat reduction, physical fitness evolution and improvement of WHOQOL-Brief domains, regardless of the trainning type conducted. © 2012 Revista Andaluza de Medicina del Deporte.

Evaluation of a radiographic method to detect tibial dyschondroplasia lesions in broilers

This study aimed at developing radiographic techniques for the early detection of dyschondroplastic lesions in the tibia of broilers. The experiment was carried out at the facilities of UNIFOR/MG and Formiga and UNIFENAS/ Alfenas with 420 one-day-old male Cobb broilers. At 20 days of age, all birds were radiographed and identified with an alpha-numeric metal ring in the right leg. At 40 days of age, 42 broilers previously selected as a function of bone mineral density and lesion thickness scores were again radiographed and scored, and then sacrificed. Their right tibia was removed for gross and histological examination of the growth plate. The results showed that radiographic techniques are correlated with gross and histological examination and that there was no significant differences among techniques (P>0.05). it was concluded that the use of radiographic examination to identify tibial dyschondroplasia in broilers precludes the use of bone mineral density to diagnose this condition. The non-parametric statistical Chi-square test at 5% significance level was used to analyze the results.

Influence of concentration, time and method of application of citric acid and sodium citrate in root conditioning.

The aim of this study was to establish the parameters of concentration, time and mode of application of citric acid and sodium citrate in relation to root conditioning. A total of 495 samples were obtained and equally distributed among 11 groups (5 for testing different concentrations of citric acid, 5 for testing different concentrations of sodium citrate and 1 control group). After laboratorial processing, the samples were analyzed under scanning electron microscopy. A previously calibrated and blind examiner evaluated micrographs of the samples. Non-parametric statistical analysis was performed to analyze the data obtained. Brushing 25% citric acid for 3 min, promoted greater exposure of collagen fibers in comparison with the brushing of 1% citric acid for 1 minute and its topical application at 1% for 3 min. Sodium citrate exposed collagen fibers in a few number of samples. Despite the lack of statistical significance, better results for collagen exposure were obtained with brushing application of 25% citric acid for 3 min than with other application parameter. Sodium citrate produced a few number of samples with collagen exposure, so it is not indicated for root conditioning.

Biocompatibility analysis of Bioglass® 45S5 and Biosilicate® implants in the rabbit eviscerated socket

Purpose: Bioactive glass and bioactive glass-ceramic cone implants were placed in the rabbit eviscerated socket to assess their biocompatibility. Methods: Fifty-one Norfolk albino rabbits underwent evisceration of the right eye followed by implantation of cones made from Bioglass® 45S5 (control group) and two types of bioactive glass-ceramic (Biosilicate®), a single- and a two-phase bioactive glass-ceramic implants into the scleral cavity. Postoperative reactions, animal behavior and socket conditions were monitored daily. Clinical exam, biochemical evaluations, and orbit computed tomographic scan were done at 7, 90, and 180 days post-procedure. After that, the animals were euthanized, and the orbital content was removed and prepared to light microscopy with morphometric evaluation and scanning electron microscopy examination. Statistical analysis was done by parametric and non-parametric analysis of variance, complemented by Dunn's and Tukey's tests (p<0.05). Results: All animals did not develop systemic toxicity throughout the experimental period and also did not have orbit infection, implant migration or extrusion. Morphological analysis demonstrated pseudocapsule around all implants. Bioglass® and single-phase Biosilicate® implants induced less inflammation and pseudocapsule formation than two-phase Biosilicate® cones. Seven days post-procedure, the inflammatory reaction was intense and gradually decreased throughout the experiment. Tissue reaction was least intense in animals receiving Bioglass® implants. Conclusions: We observe discrete differences among the studied materials, with best responses obtained with use of Bioglass® 45S5 and single-phase Biosilicate®. The authors agree these implants might be useful in the management of the anophthalmic socket. © 2012 Informa Healthcare USA, Inc.

Assessment of eyebrow position before and after upper eyelid blepharoplasty

Objective: Assess the occurrence of secondary brow ptosis after upper lid blepharoplasty. Methods: Forty-five individuals (n90 brows) submitted to upper lid blepharoplasty, were assessed by means of a comparative analysis using pre- and post-operatively digital photographs, in the primary position of the eye. The images were processed using ImageJ software, transferred to a computer, to an electronic Microsoft Excel 2002® worksheet. Angular measurements were used, taking the lateral canthal angle of the brow, the most medial point of the brow, the medial canthal angle and the lateral canthal angle of the lid as anatomical reference points. When the outer angles were reduced or the inner angles increased after surgery this was considered a brow ptosis. Individuals who had undergone lid surgery associated with the eyebrow, previous eyebrow surgery and those with eyelid ptosis were excluded. The difference between the pre-operative and post-operative measurements were analyzed statistically using the Student's t-test for paired samples and the angular variation was compared with their corresponding contralateral sample using Wilcoxon's non-parametric test. Results: The measurements obtained after the blepharoplasty show significant variations from those before the surgery, indicating that the correction of redundant tissues in the brow accentuates the tendency of the eyebrow to move down. The alterations are more important in the lateral portion of the eyebrow and they occur bilaterally. Conclusion: The assessment of angular measurements obtained pre- and post-operatively showed that there are secondary changes in the position of the eyebrow as a result of upper eyelid blepharoplasty. © 2012 Informa Healthcare USA, Inc.

Genotoxicity of the medicinal plant Maytenus robusta in mammalian cells in vivo.

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