Quantitative analysis of aluminum dross by the Rietveld method

Aluminum white dross is a valuable material principally due to its high metallic aluminum content. The aim of this work is to develop a method for quantitative analysis of aluminum white dross with high accuracy. Initially, the material was separated into four granulometric fractions by means of screening. Two samples of each fraction were obtained, which were analyzed by means of X-ray fluorescence and energy dispersive spectroscopy in order to determine the elements present in the samples. The crystalline phases aluminum, corundum, spinel, defect spinel, diaoyudaoite, aluminum nitride, silicon and quartz low were identified by X-ray diffraction. The quantitative phase analysis was performed by fitting the X-ray diffraction profile with the Rietveld method using the GSAS software. The following quantitative results were found: 77.8% aluminum, 7.3% corundum, 2.6% spinel, 7.6% defect spinel, 1.8% diaoyudaoite, 2.9% aluminum nitride, and values not significant of quartz and silicon.

Candida albicans and Candida tropicalis in Oral Candidosis: Quantitative Analysis, Exoenzyme Activity, and Antifungal Drug Sensitivity

Candida albicans and C. tropicalis obtained from whole saliva of patients presenting signs of oral candidosis were assayed for quantification of colony forming units, exoenzyme activity (phospholipase and proteinase) and antifungal drug sensitivity (amphotericin B, fluconazole and itraconazole) by the reference method of the Clinical and Laboratory Standards Institute. The number of colony forming units per milliliter varied according to the Candida species involved and whether a single or mixed infection was present. Proteinase activity was observed in both C. albicans and C. tropicalis, but phospholipase activity was noted only in C. albicans. In vitro resistance to antifungals was verified in both species, but C. tropicalis appears to be more resistant to the tested antifungals than C. albicans.

Quantitative Analysis of Placental Vasculature by Three-Dimensional Power Doppler Ultrasonography in Normal Pregnancies From 12 to 40 Weeks of Gestation

Evaluate the distribution and variation of placental vascular indices according to gestational age and placental volume. From March to November 2007, three-dimensional (3D)-power Doppler ultrasound was performed in 295 normal pregnancies from 12 to 40 weeks of gestation. Using the same preestablished settings for all patients, power Doppler was applied to the placenta and placental Volume was obtained by the rotational technique (VOCAL(TM)). The 3D-power histogram was used to determine the placental vascular indices: vascularization index (VI), flow index (FI) and vascularization-flow index (VFI). The placental vascular indices were then plotted against gestational age and placental volume. All placental vascular indices showed constant distribution throughout gestation. A tendency for a reduction in placental vascular indices with increased placental volume was observed, but was only statistically significant when placental FI was considered (p < 0.05). All placental vascular indices estimated by 3D-power Doppler ultrasonography presented constant distribution throughout gestation, despite the increase in placental volume according to gestational age. (C) 2008 Elsevier Ltd. All rights reserved.

A quantitative analysis of the nerve fibres of the acetabular periosteum of dogs

There are many techniques for the treatment of hip dysplasia, and novel research is currently being undertaken in the hope of obtaining more efficient and less traumatic techniques. The denervation of the hip joint capsule is a simple and effective technique that allows recovery of the functional activity of the affected limbs in significantly less time than other techniques. This surgical procedure consists of removing the acetabular periosteum, thus eliminating the nerve fibres with consequent analgesia. The aim of this investigation was to quantify the number of nerve fibres present in different regions of the acetabular periosteum. The knowledge of regional differences is potentially valuable for the refining of the denervation technique of the hip joint capsule. Thirty canine acetabular fragments were used to compare the nerve fibre density of the periosteum. The results showed a significant difference between the mean density of nerve fibres at the cranial and dorsal-lateral portion (approximately 75 fibres/mm(2)) and caudal lateral portion (approximately 60 fibres/mm(2)) of the acetabulum. Those fibres at the pedosteum are almost positioned in a sagittal plane, pointing towards the joint capsule, suggesting the some density in the latter region. These results indicate a new approach to the articular denervation technique, thus obtanining even better results for the treatment of hip dysplasia in dogs.

Quantitative analysis of Langerhans` cells in oral chronic graft-vs.-host disease

The Langerhans cells (LCs) are scattered throughout the epithelium of skin and mucosa and have been associated with the graft-vs.-host disease (GVHD), which is the highest cause of morbidity and mortality in patients who underwent bone marrow transplant (BMT). This study aims at quantifying the LCs in the oral chronic GVHD (cGVHD). Microscopic sections from biopsies carried out in the buccal mucosa of 40 patients who underwent allogenic BMT and developed (20) or not (20) oral cGVHD (Groups 1 and 2, respectively) were utilised. For the control group, free surgical margins of 20 biopsies of non-inflammatory lesions in the buccal mucosa (Group 3) were used. The sections were studied in routine colouration and immunostained for CD1a. Group 1 (with cGVHD) presented a greater number of Langerhans` cells/mm(2) (50.6 +/- 37.2) when compared with the other groups (Group 2, 23.11 +/- 19.7; Group 3, 16.6 +/- 17.3). Our results suggest a greater recruitment of LCs in patients transplanted with cGVHD, probably as a result of cytokines secreted by the inflammatory cells.

Inflammatory Papillary Hyperplasia of the Palate: Quantitative Analysis of Candida albicans and its Negative Correlation with Microscopic and Demographic Aspects

Inflammatory papillary hyperplasia of the palate (IPHP) is a tissue-reactive overgrowth characterized by hyperemic mucosa with nodular or papillary appearance in the palate. The exact pathogenesis is still unclear. In this study, the presence of Candida albicans in the epithelial lining was evaluated using the indirect immunofluorescence staining technique. Strongly stained C albicans was observed only in the lesions of the IPHP group. Therefore, the detection of C albicans in almost all samples from IPHP tissue enabled a suggestion as to the microbial etiology of the disease, since the use of dental prostheses was reported. Int J Prosthodont 2011;24:235-237

Descriptive Sensory Analysis and Acceptance of Stingless Bee Honey

Stingless bee honey samples were evaluated by sensory descriptive analysis using free choice profile methodology. Appearance, flavor, and aroma were described and the data were treated with Generalized Procrustes Analysis. Individual descriptive terms ranged from 8 to 20. Plotting the samples in a bidimensional plan indicated that appearance attributes (color and viscosity) and sweet, sour and acid flavor were strongly correlated with x axis (Dimension 1) while coconut, wood, acid, sour, and sweet flavor aroma attributes were correlated with y axis (Dimension 2). The affective test was also performed and with the exception of the Melipona scutellaris honey, all the other samples showed good acceptance. Honeys that were described as sweeter and less acid were preferred by nontrained assessors, indicating that the regular consumer recognizes honey produced by Apis mellifera bee as a standard.

Diversity and quantitative analysis of Archaea in aggressive periodontitis and periodontally healthy subjects

P>Aim To investigate the diversity, levels and proportions of Archaea in the subgingival biofilm of generalized aggressive periodontitis (GAgP; n=30) and periodontally healthy (PH; n=30) subjects. Materials and methods Diversity was determined by sequencing archaeal 16S rRNA gene libraries from 20 samples (10/group). The levels and proportions of Archaea were analysed by quantitative PCR (qPCR) in four and two samples/subject in GAgP and PH groups, respectively. Results Archaea were detected in 27/28 subjects and 68% of the sites of the GAgP group, and in 26/30 subjects and 58.3% sites of the PH group. Methanobrevibacter oralis was found in all 20 samples studied, Methanobacterium curvum/congolense in three GAgP and six PH samples, and Methanosarcina mazeii in four samples from each group. The levels and proportions of Archaea were higher in GAgP than in PH, whereas no differences were observed between the two probing depth category sites from the GAgP group. Conclusion Archaea were frequently found in subjects with periodontal health and GAgP, especially M. oralis. However, the higher levels and proportions (Archaea/total prokaryotes) of this domain observed in GAgP in comparison with PH subjects indicate a possible role of some of these microorganisms as an environmental modifier in GAgP.

Quantitative analysis of indexed publications on seventeen model organisms in nine countries, from 1974 to 2006

Developed countries have an even distribution of published papers on the seventeen model organisms. Developing countries have biased preferences for a few model organisms which are associated with endemic human diseases. A variant of the Hirsch-index, that we call the mean (mo)h-index (""model organism h-index""), shows an exponential relationship with the amount of papers published in each country on the selected model organisms. Developing countries cluster together with low mean (mo)h-indexes, even those with high number of publications. The growth curves of publications on the recent model Caenorhabditis elegans in developed countries shows different formats. We also analyzed the growth curves of indexed publications originating from developing countries. Brazil and South Korea were selected for this comparison. The most prevalent model organisms in those countries show different growth curves when compared to a global analysis, reflecting the size and composition of their research communities.

Synchrotron X-ray imaging via ultra-small-angle scattering: principles of quantitative analysis and application in studying bone integration to synthetic grafting materials

Optimized experimental conditions for extracting accurate information at subpixel length scales from analyzer-based X-ray imaging were obtained and applied to investigate bone regeneration by means of synthetic beta-TCP grafting materials in a rat calvaria model. The results showed a 30% growth in the particulate size due to bone ongrowth/ingrowth within the critical size defect over a 1-month healing period.

A powder X-ray diffraction method for detection of polyprenylated benzophenones in plant extracts associated with HPLC for quantitative analysis

A robust, direct, rapid and non-destructive X-ray diffraction crystallography method to detect the polyprenylated benzophenones 7-epi-clusianone (1) and guttiferone A (2) in extracts from Garcinia brasiliensis is presented. Powder samples of benzophenones 1 and 2, dried hexane extracts from G. brasiliensis seeds and fruit`s pericarp, and the dried ethanolic extract from G. brasiliensis seeds were unambiguously characterized by powder X-ray diffractometry. The calculated X-ray diffraction peaks from crystal structures of analytes 1 and 2, previously determined by single-crystal X-ray diffraction technique, were overlaid to those of the experimental powder diffractograms, providing a practical identification of these compounds in the analyzed material and confirming the pure contents of the powder samples. Using the X-ray diffraction crystallography method, the studied polyprenylated benzophenones were selectively and simultaneously detected in the extracts which were mounted directly on sample holder. In addition, reference materials of the analytes were not required for analyses since the crystal structures of the compounds are known. High performance liquid chromatography analyses also were comparatively carried out to quantify the analytes in the same plant extracts showing to be in agreement with X-ray diffraction crystallography method. (C) 2010 Elsevier B.V. All rights reserved.

Quantitative ferromagnetic resonance analysis of CD133 stem cells labeled with iron oxide nanoparticles

The aim of this work is to provide a quantitative method for analysis of the concentration of superparamagnetic iron oxide nanoparticles (SPION), determined by means of ferromagnetic resonance (FMR), with the nanoparticles coupled to a specific antibody (AC133), and thus to express the antigenic labeling evidence for the stem cells C D133(+). The FMR efficiency and sensitivity were proven adequate for detecting and quantifying the low amounts of iron content in the C D133(+) cells (similar to 6.16 x 10(5) pg in the volume of 2 mu l containing 4.5 x 1011 SPION). The quantitative method led to the result of 1.70 x 10(-13) mol of Fe (9.5 pg), or 7.0 x 10(6) nanoparticles per cell. For the quantification analysis via the FMR technique it was necessary to carry out a preliminary quantitative visualization of iron oxide-labeled cells in order to ensure that the nanoparticles coupled to the antibodies are indeed tied to the antigen at the stem cell surface and that the cellular morphology was conserved, as proof of the validity of this method. The quantitative analysis by means of FMR is necessary for determining the signal intensity for the study of molecular imaging by means of magnetic resonance imaging (MRI).

Subcutaneous connective tissue response to primary root canal filling materials

This study evaluated the response of the subcutaneous connective tissue of BALB/c mice to root filling materials indicated for primary teeth: zinc oxide/eugenol cement (ZOE), Calen paste thickened with zinc oxide (Calen/ZO) and Sealapex sealer. The mice (n=102) received polyethylene tube implants with the materials, thereby forming 11 groups, as follows: I, II, III: Calen/ZO for 7, 21 and 63 days, respectively; IV, V, VI: Sealapex for 7, 21 and 63 days, respectively; VII, VIII, IX: ZOE for 7, 21 and 63 days, respectively; X and XI: empty tube for 7 and 21 days, respectively. The biopsied tissues were submitted to histological analysis (descriptive analysis and semi-quantitative analysis using a scoring system for collagen fiber formation, tissue thickness and inflammatory infiltrate). A quantitative analysis was performed by measuring the area and thickness of the granulomatous reactionary tissue (GRT). Data were analyzed by Kruskal-Wallis, ANOVA and Tukey's post-hoc tests (?=0.05). There was no significant difference (p>0.05) among the materials with respect to collagen fiber formation or GRT thickness. However, Calen/ZO produced the least severe inflammatory infiltrate (p<0.05). The area of the GRT was significantly smaller (p<0.05) for Calen/ZO and Sealapex. In conclusion, Calen/ZO presented the best tissue reaction, followed by Sealapex and ZOE.

Subcutaneous tissue response of isogenic mice to calcium hydroxide-based pastes with chlorhexidine

This study was evaluated the response of subcutaneous connective tissue of isogenic mice to calcium hydroxide-based pastes with chlorhexidine digluconate (CHX). Seventy isogenic male BALB/c mice aged 6-8 weeks and weighing 15-20 g were randomly assigned to 8 groups. The animals received polyethylene tube implants as follows: Groups I, II, and III (n=10) - Calen® paste mixed with 0.4% CHX (experimental paste; Calen/CHX) for 7, 21, and 63 days, respectively; Groups IV, V, and VI (n=10) - UltraCal™ paste mixed with 2% CHX (experimental paste supplied by Ultradent Products Inc.; Ultracal/CHX) for 7, 21, and 63 days, respectively; and Groups VII and VIII (n=5): empty tube for 7 and 21 days, respectively. At the end of the experimental periods, the implants were removed together with the surrounding tissues (skin and subcutaneous connective tissue). The biopsied tissues were subjected to routine processing for histological analysis. Using a descriptive analysis and a four-point (0-3) scoring system, the following criteria were considered for qualitative and quantitative analysis of the tissue around the implanted materials: collagen fiber formation, tissue thickness and inflammatory infiltrate. A quantitative analysis was performed by measuring the thickness (µm), area (µm²) and perimeter (µm) of the reactionary granulomatous tissue formed at the tube ends. Data were analyzed statistically by the Kruskal-Wallis test and Dunn's post-test (α=0.05). Calen/CHX showed biocompatibility with the subcutaneous and reactionary tissues, with areas of discrete fibrosis and normal conjunctive fibrous tissue, though without statistically significant difference (p>0.05) from the control groups. In Groups I to III, there was a predominance of score 1, while in Groups IV to VI scores 2 and 3 predominated for all analyzed parameters. UltraCal/CHX, on the other hand, induced the formation of an inflammatory infiltrate and abundant exudate, suggesting a persistent residual aggression from the material, even 63 days after implant placement. In conclusion, the Calen paste mixed with 0.4% CHX allowed an adequate tissue response, whereas the UltraCal paste mixed with 2% CHX showed unsatisfactory results.

Evaluation of Femtosecond Laser-Induced Breakdown Spectroscopy for Analysis of Animal Tissues

The aim of this work was to evaluate the performance of femtosecond laser-induced breakdown spectroscopy (fs-LIBS) for the determination of elements in animal tissues. Sample pellets were prepared from certified reference materials, such as liver, kidney, muscle, hepatopancreas, and oyster, after cryogenic grinding assisted homogenization. Individual samples were placed in a two-axis computer-controlled translation stage that moved in the plane orthogonal to a beam originating from a Ti:Sapphire chirped-pulse amplification (CPA) laser system operating at 800 mu and producing a train of 840 mu J and 40 fs pulses at 90 Hz. The plasma emission was coupled into the optical fiber of a high-resolution intensified charge-coupled device (ICCD)-echelle spectrometer. Time-resolved characteristics of the laser-produced plasmas showed that the best results were obtained with delay times between 80 and 120 ns. Data obtained indicate both that it is a matrix-independent sampling process and that fs-LIBS can be used for the determination of Ca, Cu, Fe, K, Mg, Na, and P, but efforts must be made to obtain more appropriate detection limits for Al, Sr, and Zn.