Experimental validation of variance estimation in the statistical energy analysis of a structural-acoustic system

The Statistical Energy Analysis (SEA) approach has largely been used in vibro-acoustic modelling to predict the averaged energy in coupled vibrating structures and acoustic cavities. The average is performed over an ensemble of nominally identical built-up systems where random responses are observed at high frequencies after excitation. Over the years, this approach has been extended to predict the energy variance employing the statistics of the Gaussian Orthogonal Ensemble, and numerical and experimental evidence has supported the predictions of the mean and variance of energy of coupled vibrating structures. However, little experimental evidence is found to validate the prediction of the variance of energy in coupled structural-acoustic systems. In this work, the mean and variance of energies predicted from a statistical energy analysis model have been validated with experimental measurements on a structural-acoustic system, comprised by a flat thin plate coupled to an enclosed acoustic volume. The structural system has been randomised by adding small masses on arbitrary positions on the plate, whereas the randomisation of the acoustic cavity is achieved by allocating rigid baffles in random positions within the acoustic volume. In general, good agreement is found between the predictions of the model and the experimental results. Bose Cor

On the existence and decay in a new thermoelastic theory with two temperatures

In this work, we study a new two-temperatures thermoelastic model. Both thermodynamic and conductive temperatures are included, being related by means of an elliptic or parabolic equation. Then, two problems are considered assuming the dependence or not on the rate conductivity temperature. Existence of solutions for the three-dimensional setting and the exponential energy decay in the one-dimensional case are shownPeer ReviewedPostprint (author's final draft

Water submetering system: how to determine the flow rates for water meters specification?

The objective of this paper is to compare the results obtained in the estimate of the design flow rates to the dimension water meters of water submetering systems in buildings by means not only from an open probabilistic model but also from the empirical method recommended by the Brazilian Standard. As the final results show considerable differences in the design flow rates estimated by both methods, it is extremely important to perform field survey in order to check the obtained values. The open probabilistic model enables the practitioner to adjust the variables related to the water use to better reflect the flow rates in the plumbing system according to the different conditions of use. Due to this advantage, its use appears to be more beneficial than the empirical method, mainly concerning submetering systems where the specification of the water meters takes into account the design flow rate.15217718

Loci identificados através de estudo de associação genômica ampla e risco de câncer do pulmão: existe algo mais?

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Effect of fuels on the piston rings of the flexfuel engines / Efeito dos combustíveis nos anéis de pistão dos motores de combustível

This study describes the wear in piston rings of the internal combustion engines. The objective was to investigate, the rings wear between two engine groups, as gasoline, alcohol or blend fuel. The piston rings were acquired in a motor parts store and engine reconditioner, cataloged, identified, and chosen the samples with high mileage. The first step involved the measurement of height, thickness and ring outer diameter, to compare them with the original measurements of the manufacturers and make comparison between the groups, gasoline and flexfuel engine. In the second step, the rugosimetric parameters of the surface of the samples were checked with a rugosimeter. In the third step, a microscopic analysis was performed by a SEM for analysis of the contact surface coating of the piston rings. It was found that differences between the two groups of piston ring in respect to the wear. So, it was concluded that the wear of the rings of the two groups of engines are similar quantitatively, however, as for the rugosimetric analysis, a great variation was observed in the rings of the flexfuel motors qualitatively, when compared with the gasoline engines rings.

The progesterone receptor Val660→Leu polymorphism and breast cancer risk

BACKGROUND: Recent evidence suggests a role for progesterone in breast cancer development and tumorigenesis. Progesterone exerts its effect on target cells by interacting with its receptor; thus, genetic variations, which might cause alterations in the biological function in the progesterone receptor (PGR), can potentially contribute to an individual's susceptibility to breast cancer. It has been reported that the PROGINS allele, which is in complete linkage disequilibrium with a missense substitution in exon 4 (G/T, valine→leucine, at codon 660), is associated with a decreased risk for breast cancer. METHODS: Using a nested case-control study design within the Nurses' Health Study cohort, we genotyped 1252 cases and 1660 matched controls with the use of the Taqman assay. RESULTS: We did not observe any association of breast cancer risk with carrying the G/T (Val660→Leu) polymorphism (odds ratio 1.10, 95% confidence interval 0.93–1.30). In addition, we did not observe an interaction between this allele and menopausal status and family history of breast cancer as reported previously. CONCLUSION: Overall, our study does not support an association between the Val660→Leu PROGINS polymorphism and breast cancer risk

In vivo inhibition of c-MYC in myeloid cells impairs tumor-associated macrophage maturation and pro-tumoral activities

Although tumor-associated macrophages (TAMs) are involved in tumor growth and metastasis, the mechanisms controlling their pro-tumoral activities remain largely unknown. The transcription factor c-MYC has been recently shown to regulate in vitro human macrophage polarization and be expressed in macrophages infiltrating human tumors. In this study, we exploited the predominant expression of LysM in myeloid cells to generate c-Myc(fl/fl) LysM(cre/+) mice, which lack c-Myc in macrophages, to investigate the role of macrophage c-MYC expression in cancer. Under steady-state conditions, immune system parameters in c-Myc(fl/fl) LysM(cre/+) mice appeared normal, including the abundance of different subsets of bone marrow hematopoietic stem cells, precursors and circulating cells, macrophage density, and immune organ structure. In a model of melanoma, however, TAMs lacking c-Myc displayed a delay in maturation and showed an attenuation of pro-tumoral functions (e.g., reduced expression of VEGF, MMP9, and HIF1α) that was associated with impaired tissue remodeling and angiogenesis and limited tumor growth in c-Myc(fl/fl) LysM(cre/+) mice. Macrophage c-Myc deletion also diminished fibrosarcoma growth. These data identify c-Myc as a positive regulator of the pro-tumoral program of TAMs and suggest c-Myc inactivation as an attractive target for anti-cancer therapy