G. Giovinco

A comparison of submicrometer particle dose between Australian and Italian people.

Alveolar and tracheobronchial-deposited submicrometer particle number and surface area data received by different age groups in Australia are shown. Activity patterns were combined with microenvironmental data through a Monte Carlo method. Particle number distributions for the most significant microenvironments were obtained from our measurement survey data and people activity pattern data from the Australian Human Activity Pattern Survey were used. Daily alveolar particle number (surface area) dose received by all age groups was equal to 3.0 × 10(10) particles (4.5 × 10(2) mm(2)), varying slightly between males and females. In contrast to gender, the lifestyle was found to significantly affect the daily dose, with highest depositions characterizing adults. The main contribution was due to indoor microenvironments. Finally a comparison between Italian and Australian people in terms of received particle dose was reported; it shows that different cooking styles can affect dose levels: higher doses were received by Italians, mainly due to their particular cooking activity.

Experimental and Theoretical Modeling of the Effective Thermal Conductivity of Rough Steel Spheroid Packed Beds

The upper and lower bounds of the effective thennal conductivity of packed beds of rough spheres are evaluated using the theoretical approach of the elementary cell for two-phase systems. The solid mechanics and thermal problems are solved and the effects of roughness and packed bed structures are also examined. The numerical solution of the thermal conduction problem through the periodic regular arrangement of steel spheroids in air is determined using the Finite Element Method. The numerical results are compared with those obtained from an experimental apparatus designed and built for this purpose

Lung cancer risk of airborne particles for Italian population.

Airborne particles, including both ultrafine and supermicrometric particles, contain various carcinogens. Exposure and risk-assessment studies regularly use particle mass concentration as dosimetry parameter, therefore neglecting the potential impact of ultrafine particles due to their negligible mass compared to supermicrometric particles. The main purpose of this study was the characterization of lung cancer risk due to exposure to polycyclic aromatic hydrocarbons and some heavy metals associated with particle inhalation by Italian non-smoking people. A risk-assessment scheme, modified from an existing risk model, was applied to estimate the cancer risk contribution from both ultrafine and supermicrometric particles. Exposure assessment was carried out on the basis of particle number distributions measured in 25 smoke-free microenvironments in Italy. The predicted lung cancer risk was then compared to the cancer incidence rate in Italy to assess the number of lung cancer cases attributed to airborne particle inhalation, which represents one of the main causes of lung cancer, apart from smoking. Ultrafine particles are associated with a much higher risk than supermicrometric particles, and the modified risk-assessment scheme provided a more accurate estimate than the conventional scheme. Great attention has to be paid to indoor microenvironments and, in particular, to cooking and eating times, which represent the major contributors to lung cancer incidence in the Italian population. The modified risk assessment scheme can serve as a tool for assessing environmental quality, as well as setting up exposure standards for particulate matter.

Differential vulnerability of retinal layers to early age-related macular degeneration: Evidence by SD-OCT segmentation analysis

PURPOSE We evaluated layer-by-layer retinal thickness in spectral-domain optical coherence tomography (SD-OCT), determined by automated segmentation analysis (ASA) software in healthy and early age-related maculopathy (ARM) eyes. METHODS There were 57 eyes (specifically, 19 healthy eyes under 60 years old, 19 healthy eyes over 60, and 19 ARM eyes) recruited into this cross-sectional study. The mean ages were 36.78 (SD, ±13.82), 69.89 (SD, ±6.14), and 66.10 (SD, ±8.67) years, respectively, in the three study groups. The SD-OCT scans were transferred into a dedicated software program that performed automated segmentation of different retinal layers. RESULTS Automated layer segmentation showed clear boundaries between the following layers: retinal nerve fiber layer (RNFL), ganglion cell layer plus inner plexiform layer (GCL+IPL), inner nuclear layer plus outer plexiform layer (INL+OPL), outer nuclear layer (ONL), and RPE complex. The thickness of the RNFL, ONL, and RPE layers did not show a statistically significant change across the three groups by ANOVA (P = 0.10, P = 0.09, P = 0.15, respectively). The thickness of GCL+IPL and INL+OPL was significantly different across the groups (P < 0.01), being reduced in the ARM eyes compared to healthy eyes, under and over 60 years old. CONCLUSIONS The early morphologic involvement of the GCL+IPL and INL+OPL layers in ARM eyes, as revealed by the ASA, could be related to early anatomic changes described in the inner retina of ARM eyes. This finding may represent a morphologic correlation to the deficits in postreceptoral retinal function in ARM eyes.

Forming Apparatus to Investigate the Effect of Temperature on the Superplastic Behaviour of Alloys

In this paper the authors show an experimental apparatus designed and made up to investigate the effect of temperature on the deformation of superp lastic alloys up to 473 K. The authors used the 3D finite volume software FLUENT ® to design the experimental apparatus. The numerical results have been employed for the system optimisation and metrological characterisation. The system was tested through bulge tests on a Pb‐Sn alloy, showing its good versatility.

Do air quality targets really represent safe limits for lung cancer risk

In order to estimate the lung cancer risk associated to airborne particles, exposure and risk-assessment studies ordinarily use particle mass concentration as dosimetry parameter. Consequently, the corresponding air quality targets are based on this metrics, neglecting the potential impact of ultrafine particles (UFPs) due to their negligible mass. The main purpose of this study was to evaluate the reliability of air quality targets in protecting Italian non-smoking people from lung cancer risk due to exposure to polycyclic aromatic hydrocarbons and some heavy metals associated with particle inhalation. A modified risk-assessment scheme was applied to estimate the cancer risk contribution from both sub-micron (mainly UFPs) and super-micron particles. We found a very high lung cancer risk related to the actual target levels due to the contribution of UFPs, in particular from indoor microenvironments. Therefore, as possible actions to reduce the lung cancer risk, we have hypothesized and tested three different scenarios: a) a reduction of the concentration of carcinogenic chemicals condensed onto particles in agreement with the current EU air pollution policy; b) the use of local ventilation systems to mitigate the exposure to cooking-generated particles; c) the improvement of the overall indoor air quality by considering a mechanical ventilation system instead of the widespread natural ventilation in order to increase the air exchange rates. Even with the simultaneous application of specific actions, performed with the best technologies available, the corresponding estimated lifetime lung cancer risk (ELCR) values for the Italian population for the entire life were equal to 1.25×10-4 and 1.23×10-4 for males and females, respectively, well higher with respect to the maximum tolerable lifetime cancer risk, 1×10-5.

Monotonicity principle in pulsed eddy current testing and its application to defect sizing

This article applies monotonicity principle to time constants in pulsed eddy current testing. This principle allows for a non-iterative imaging method for defects in conducting materials. The source free response in pulsed eddy current testing consists of linear combination of exponential decaying waveforms. A major challenge of this method is to accurately estimate the time constants from measurement of such responses. Preliminary results of estimating dominant time constants are presented. Potentially, this information can be used to predict the size of a volumetric defect regardless of its location, i.e. this method is robust in the case of both surface and buried defects.

Effectiveness of finite element calculation methods (FEM) on high performance pressure balances in liquid media up to 200?MPa

In the framework of a bilateral cooperation between the I.N.RI.M./University of Cassino and DH Instruments, the authors tested the effectiveness of finite element methods (FEM) in predicting the behaviour of high performance pressure balances that are used extensively in national metrology laboratories and industry.The pressure balances under investigation operate up to 200 MPa (free deformation and controlled clearance types).The results of FEM calculations are presented, giving information on the baseline models adopted. All FEM numerical results are discussed and compared with the typical characteristics of the piston–cylinders observed in the metrology laboratory of the pressure balance manufacturer. Conclusions are drawn in terms of reliability of results based on an estimation of the parameters that have the largest influence on the uncertainty in the investigated quantities.

An elasto-plastic model of thermal contact conductance between nominally flat surfaces in vacuum

Thermal contact conductance is an important parameter in a wide range of thermal phenomena, and consequently a large number of experimental, numerical and statistical investigations have been presented in literature. An analysis of thermal contact resistance is carried out to predict heat transfer between nominally flat, parallel rough surfaces in contact, in absence of interstitial conductive media (i.e. in vacuum), by means of a statistical approach. The rough surface is described through a probabilistic model based on the peak height variability and invariant asperity curvature radius

Influence of contact mechanics in the prediction of the effective thermal conductivity of spheroid packed beds

Thermal contact conductance is an important parameter in a wide range of thermal phenomena, and consequently a large number of experimental, numerical and statistical investigations have been carried out in literature. In the present paper an analysis of thermal contact resistance is carried out to predict heat transfer between spherical rough surfaces in contact, by means of a statistical approach. The micro-geometry of the surface is described through a probabilistic model based on the peak height variability and invariant asperity curvature radius. The numerical model has been applied to evaluate the effective thermal conductivity of packed beds of steel spheroids and validated through the comparison with the experimental data obtained by means of an apparatus designed and build up for this purpose.Copyright