Characteristics of the double-torsion test to determine the R-curve of ceramic materials

Double-torsion tests were carried out on a commercial ceramic floor tile to verify whether this test is suitable for determining the R-curve of ceramics. The instantaneous crack length was obtained by means of compliance calibration, and it was found that the experimental compliance underestimates the real crack length. The load vs. displacement curves were also found to drop after maximum loading, causing the stress intensity factor to decline. The R-curves were calculated by two methods: linear elastic fracture mechanics and the energetic method. It was obtained that the average values of crack resistance, R, and the double of the work of fracture, 2 · γwof, did not depend on notch length, a0, which is a highly relevant finding, indicating that these parameters were less dependent on the test specimen's geometry. The proposal was to use small notches, which produce long stable crack propagation paths that in turn are particularly important in the case of coarse microstructures.

Intraosseous schwannoma mimicking a periapical lesion on the adjacent tooth: Case report

Aim: To present an additional case of intraosseous schawannoma involving the apical area in the mandibular alveolar bone mimicking an inflammatory periapical lesion. Summary: This article describes a case of schwannoma periapically located mimicking an inflammatory periapical lesion in the mandible of a 34-year-old female. Diagnostic and therapeutic problems can occur when this lesion is misinterpreted as being endodontic in origin. The diagnosis, radiograph, immunohistochemical aspects and treatment are also discussed. Key learning points: • Intraosseous schwannoma is a rare unilocular radiolucency that when located periapically could be misdiagnosed as an endodontic lesion and result in unnecessary root canal treatment. • The vitality of the pulp is an important test to exclude lesions of inflammatory origin. • Histological examination is important to establish the diagnosis of lesions in the periradicular region. © 2007 International Endodontic Journal.

Technology assessment for power quality mitigation devices - Micro-DVR case study

This work presents a case study on technology assessment for power quality devices. A system compatibility test protocol for power quality mitigation devices was developed in order to evaluate the functionality of three-phase voltage restoration devices. In order to case test this test protocol, a development platform with reduced power for DVR (Dynamic Voltage Restorer), the Micro-DVR, was tested, and results were discussed based on voltage disturbances standards. ©2008 IEEE.

Oral stomatitis induced by endogenous progesterone: Case report

Oral stomatitis induced by endogenous progesterone is a rare clinical condition which may be associated with cutaneous involvement. That is probably due to the peak of progesterone production during the luteal phase of the menstrual cycle. In the present case report, a 21-year-old patient displayed recurrent ulcerative lesions located on the buccal mucosa or the upper lip, on a monthly basis since the age of 15. Such lesions would always manifest themselves on the second day until the end of the menstrual cycle. © 2009 Informa UK Ltd All rights reserved.

Performance of CMS hadron calorimeter timing and synchronization using test beam, cosmic ray, and LHC beam data

This paper discusses the design and performance of the time measurement technique and of the synchronization systems of the CMS hadron calorimeter. Time measurement performance results are presented from test beam data taken in the years 2004 and 2006. For hadronic showers of energy greater than 100 GeV, the timing resolution is measured to be about 1.2 ns. Time synchronization and out-of-time background rejection results are presented from the Cosmic Run At Four Tesla and LHC beam runs taken in the Autumn of 2008. The inter-channel synchronization is measured to be within 2 ns. © 2010 IOP Publishing Ltd and SISSA.

Rigidities and fiscal space in Latin America: a comparative case study

Includes Bibliography

Muscular strength, bone density and body composition of a woman with systemic lupus erythematosus submitted to a resistance training program: A case report

Introduction. Physical activity can provide long-term benefits for systemic lupus erythematosus (SLE). Objective. This study sought to demonstrate the effects of progressive resistance training on the muscular strength, bone mineral density (BMD) and body composition of pre-menopausal women with SLE undergoing glucocorticoid (GC) treatment. Materials and Methods. This is the case report of a 43-year-old African-South American premenopausal woman with non-extensive SLE and low bone density. A six-month program with three bimonthly cycles of 70%, 80%, and 90% intensity according to the 10 maximum-repetition test was used. Dual-energy X-ray absorptiometry (DXA) was used to measure the BMD, T-scores and body composition, and indirect fluorescence was used to measure the levels of antinuclear antibodies. Student's t-test was used. Results. Statistical improvement was noted in all strength exercises, including the 45° leg press (Δ%=+50%, p<0.001) and knee extension (Δ%=+15%, p=0.003) to maintain the BMD of the L2-L4 lumbar (Δ%=+0.031%; p=0.46) as well as the trochanter (Δ%=+0.037%; p=0.31) and BMI (Δ%=-0.8, p=0.54). Conclusion. In this case study, the presented methodology had a positive effect on strength and contributed to the maintenance of BMD and body composition in a woman with SLE undergoing GC treatment. © 2012 Revista Andaluza de Medicina del Deporte.

Interdisciplinary approach to the management of Ewing sarcoma: A case report

Ewing sarcoma is a common primary bone malignancy occurring in childhood and adolescence. This case report describes a 4-year-old female patient who had Ewing sarcoma in the left clavicular region. The patient underwent total excision of the left clavicle and subsequently developed periodontitis and multiple carious lesions after chemotherapy. Caries risk and salivary flow rate tests were performed, followed by periodontal treatment, topical fluoride application, restoration of caries, and oral hygiene instruction. The care of this patient demonstrates that an interdisciplinary approach is essential to eliminate all foci of infection, minimize morbidity, and improve the patient's general health before, during, and after oncological treatment. © 2012 Special Care Dentistry Association and Wiley Periodicals, Inc.

Composition and interrelationships of a large Neotropical freshwater fish group, the subfamily Cheirodontinae (Characiformes: Characidae): A case study based on mitochondrial and nuclear DNA sequences

•Relationships of Cheirodontinae based on a broad taxonomic sample.•Results reject the monophyly of Cheirodontinae as previously conceived.•Exclusion of Amazonspinther and Spintherobolus from the subfamily Cheirodontinae.•The removal of Leptagoniates pi of the genus Leptagoniates and inclusion in Cheirodontinae.•Division of Cheirodontinae in three newly defined monophyletic tribes. Characidae is the most species-rich family of freshwater fishes in the order Characiformes, with more than 1000 valid species that correspond to approximately 55% of the order. Few hypotheses about the composition and internal relationships within this family are available and most fail to reach an agreement. Among Characidae, Cheirodontinae is an emblematic group that includes 18 genera (1 fossil) and approximately 60 described species distributed throughout the Neotropical region. The taxonomic and systematic history of Cheirodontinae is complex, and only two hypotheses about the internal relationships in this subfamily have been reported to date. In the present study, we test the composition and relationships of fishes assigned to Cheirodontinae based on a broad taxonomic sample that also includes some characid incertae sedis taxa that were previously considered to be part of Cheirodontinae. We present phylogenetic analyses of a large molecular dataset of mitochondrial and nuclear DNA sequences. Our results reject the monophyly of Cheirodontinae as previously conceived, as well as the tribes Cheirodontini and Compsurini, and the genera Cheirodon, Compsura, Leptagoniates, Macropsobrycon, Odontostilbe, and Serrapinnus. On the basis of these results we propose: (1) the exclusion of Amazonspinther and Spintherobolus from the subfamily Cheirodontinae since they are the sister-group of all remaining Characidae; (2) the removal of Macropsobrycon xinguensis of the genus Macropsobrycon; (3) the removal of Leptagoniates pi of the genus Leptagoniates; (4) the inclusion of Leptagoniates pi in the subfamily Cheirodontinae; (5) the removal of Cheirodon stenodon of the genus Cheirodon and its inclusion in the subfamily Cheirodontinae under a new genus name; (6) the need to revise the polyphyletic genera Compsura, Odontostilbe, and Serrapinnus; and (7) the division of Cheirodontinae in three newly defined monophyletic tribes: Cheirodontini, Compsurini, and Pseudocheirodontini. Our results suggest that our knowledge about the largest Neotropical fish family, Characidae, still is incipient. © 2013 Elsevier Inc..

PLA and Organoclays Nanocomposites: Degradation Process and Evaluation of ecotoxicity Using Allium cepa as Test Organism

In this study, nanocomposites of PLA and organoclays Cloisite 20A and Cloisite 30B were prepared by the melt intercalation method and the obtained samples were characterized by transmission electron microscopy (TEM). Since composting is an important proposal to the final disposal of biopolymers, the influence of clays on the hydrolytic degradation process of PLA was evaluated by visual analysis and monitoring of molecular weight after periods of 15 and 30 days of degradation in compost. After degradation of the materials in composting environment, the evaluation of cytotoxic, genotoxic and mutagenic effects of compost aqueous extract was carried out using a bioassay with Allium cepa as test organism. The TEM micrographs permitted the observation of different levels of dispersion, including exfoliated regions. In the evaluation of hydrolytic degradation it was noted that the presence of organoclays can decrease the rate of degradation possibly due to the barrier effect of clay layers and/or the higher degree of crystallinity in the nanocomposite samples. Nevertheless, even in the case of nanocomposites, the molecular weight reduction was significant, indicating that the composting process is favorable to the chain scission of PLA in studied materials. In the analysis performed by the bioassay using A. cepa as test organism, it was found that after degradation of the PLA and its nanocomposites the aqueous extract of compost samples induced a decreasing in the mitotic index and an increasing in the induction of chromosomal abnormalities. These results were statistically significant in relation to the negative control (distilled water). By comparing the results obtained for the nanocomposites in relative to pure polymer, there were no statistically significant differences. The types of the observed chromosomal aberrations indicated a possible genotoxic effect of the materials, which may be related to an aneugenic action of PLA degradation products. © 2013 Springer Science+Business Media New York.

Mating in the pseudogamic apomictic Anemopaegma acutifolium DC: Another case of pseudo-self-compatibility in Bignoniaceae?

Self-compatibility in apomictic pseudogamic species is considered fundamental to assure reproduction by seeds in extreme situations, making apomictic species more advantageous than sexual ones in these scenarios. Anemopaegma acutifolium is a polyploidy, apomictic sporophytic species with no endosperm development in ovules of unpollinated pistils, which indicates obligate pseudogamy. Thus, the aim of the present work is to study the breeding system and post-pollination events to test if there is similar pseudogamous development irrespective of pollination treatment. We analysed fruit and seed set obtained in controlled experimental pollinations, as well as embryo number per seed, and the progress of ovule penetration, fertilisation and early endosperm development between self- and cross-pollinated pistils. We found that the species is self-fertile and that spontaneous selfing fruit set is also possible, although emasculated flowers never form fruits. Selfed pistils were as efficient as crossed ones for all parameters analysed, except for a delay in endosperm development observed in the former that may be an effect of the late-acting self-incompatibility. Therefore, the avoidance of selfed pistil abortion seems to be promoted by the presence of adventitious embryos and a normal endosperm. We conclude that A. acutifolium shows apomixis-related pseudo-self-compatibility, as in other self-fertile apomictic species of Bignoniaceae, which confer reproductive assurance and increases fruit-set and persistence ability in fast-changing tropical habitats. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

New strategies for planning and performance evaluation of wireless networks: case studies based on the cross-layer approach

The use of wireless local area networks, called WLANs, as well as the proliferation of the use of multimedia applications have grown rapidly in recent years. Some factors affect the quality of service (QoS) received by the user and interference is one of them. This work presents strategies for planning and performance evaluation through an empirical study of the QoS parameters of a voice over Internet Protocol (VoIP) application in an interference network, as well as the relevance in the design of wireless networks to determine the coverage area of an access point, taking into account several parameters such as power, jitter, packet loss, delay, and PMOS. Another strategy is based on a hybrid approach that considers measuring and Bayesian inference applied to wireless networks, taking into consideration QoS parameters. The models take into account a cross layer vision of networks, correlating aspects of the physical environment, on the signal propagation (power or distance) with aspects of VoIP applications (e.g., jitter and packet loss). Case studies were carried out for two indoor environments and two outdoor environments, one of them displaying main characteristics of the Amazon region (e.g., densely arboreous environments). This last test bed was carried out in a real system because the Government of the State of Pará has a digital inclusion program called NAVEGAPARÁ.

The AIDS epidemic in the Amazon region: a spatial case-control study in Rondonia, Brazil

OBJETIVO Analisar mudanças espaciais no risco de Aids e a relação entre incidência da doença e variáveis socioeconômicas. MÉTODOS Estudo caso-controle espacial, de base populacional, realizado em Rondônia, Brasil, com 1.780 casos notificados pelo Sistema de Vigilância Epidemiológica e os controles a partir de dados demográficos de 1987 a 2006. Os casos foram agrupados em cinco períodos de cinco anos consecutivos. Um modelo aditivo generalizado foi ajustado aos dados. O status dos indivíduos (caso ou controle) foi considerado como a variável dependente e independente: um alisamento ( spline ) bidimensional das coordenadas geográficas e variáveis socioeconômicas municipais. Os valores observados para o teste Moran I foram comparados com a distribuição de referência dos valores obtidos em condições de aleatoriedade espacial. RESULTADOS O risco de Aids apresentou padrão espacial e temporal marcado. A incidência associou-se a indicadores socioeconômicos municipais, como urbanização e capital humano. As maiores taxas de incidência de Aids ocorreram em municípios ao longo da rodovia BR-364; os resultados do teste Moran I mostram correlação espacial positiva associada à contiguidade dos municípios com a rodovia, no terceiro e quarto períodos (p = 0,05). CONCLUSÕES A incidência da doença foi maior em municípios de maior riqueza econômica e urbanização e naqueles cortados pelas estradas principais de Rondônia. O rápido desenvolvimento associado à ocupação de regiões remotas pode ser acompanhado por aumento de riscos à saúde.

Court cleaning behavior of the white-bearded manakin (manacus manacus) and a test of the anti-predation hypothesis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Plant iononne diagnosis using sound balances: case study with mango (Mangifera Indica)

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