Papers by Antonio Cavaliere
Clean Air: International Journal on Energy for a Clean Environment, 2003
ICHMT Third International Symposium on Radiative Transfer, 2001
Progress in Energy and Combustion Science, 2001
This is a synoptic overview of a selection of works dealing with single diffusive structures, wit... more This is a synoptic overview of a selection of works dealing with single diffusive structures, with their mutual interaction in simple flows and their statistical modeling in complex flows. The focus is on reacting conditions pertaining to gaseous diffusion flames, but isothermal structures are also described when they are of some conceptual interest. This paper considers only few representative works for each subject, which are functional in explaining the key characteristics of the diffusive structures. The extension, given to single subjects, is not weighed according to the number of related publications but on the relevance to the basic understanding of the general framework concerning diffusion flames. One-dimensional structures are first discussed. They are ordered according to the number of balance equation terms needed for their description. Two-dimensional (2D) structures are then introduced following an order based on their convolution level. Some pioneering work on three-dimensional structures is further quoted. The temporal evolution of simple structures in quiescent or simple flowing 2D systems is considered. The latter case is exploited to present classification of diffusion-controlled mixing regimes. Modeling characterization approach of turbulent diffusion flames is also described in order to yield a self-sufficient didactic presentation. The approach based on the flame surface density model is specifically discussed because of its potential use in the determination of qualitative and quantitative features of simple diffusion flames.
Combustion and Flame, 1993
The low-temperature oxidation of higher molecular mass hydrocarbons and its relationship with the... more The low-temperature oxidation of higher molecular mass hydrocarbons and its relationship with the autoignition has been studied by following the oxidation of n-heptane and n-tetradecane at temperature and pressure conditions closer to the actual conditions occurring inside internal combustion engines. The oxidation of n-heptane, a typical low-octane-number component of gasoline, has been studied in a jet stirred flow reactor operating at 0.2 MPa by measuring the compositional changes of the reaction products as the temperature increases in the low-temperature regimes typical of the “end-gas” in a spark-ignition engine. The oxidation scheme used for the interpretation of n-heptane data is in the framework of the low-temperature oxidation of light hydrocarbons. Oxygenated compounds, that is, aldehydes, and ketones, are preferentially formed at low temperature and decrease as temperature increases giving rise to CO2 and olefin formation. The autoignition of n-tetradecane, a typical component of practical diesel blends, was studied by injecting the liquid fuel in a quiescent high-temperature and high-pressure oxidative environment, that is, under diesel-like conditions, simplified from the aerodynamic point of view. Its chemical evolution was followed by sampling the reaction products at different air inlet temperatures. Chemical data have been determined for the oxidation of a complex fuel, such as n-tetradecane, injected in diesel-like conditions, where physical and fluid-dynamic effects are supposed to control the oxidation process. This can be interpreted by simple kinetic schemes of low-temperature oxidation, commonly foreseen and validated for simple experiments and light fuels.
Experimental Thermal and Fluid Science, 2000
A comparative analysis of the stability regimes of three different electrohydrodynamic atomizatio... more A comparative analysis of the stability regimes of three different electrohydrodynamic atomization (electrospray) systems is presented. Availability of a high resolution imaging system allowed for a direct visualization of the breakup mechanisms. Both liquid flow rate and applied voltage are varied in a large grid of values in order to build up a database of the observable jet breakup regimes. The exploited conditions have been chosen with the purpose of evidencing the relative influences of geometrical, electrical and fluid_dynamical effects at various working conditions. Experimental results shed light on the complex interaction between the controlling parameters and resulted in the formulation of some necessary conditions for the occurrence of stable jet regimes. The final conclusion of the paper is the recognition of the actual limitation in the mass flow rate range where such regime can be stabilized. Nevertheless some suggestion comes for the exploitation of atomization condition different from the classical Taylor cone jet that could be successfully exploited either in combustion systems or other technological application.
Atomization and Sprays, 2007
Breast, 2001
Previously we have demonstrated that determination of oestrogen (ER) and progesterone (PR) recept... more Previously we have demonstrated that determination of oestrogen (ER) and progesterone (PR) receptors by immunocytochemical assay (ICA) on frozen sections (FS) and cytological smears with image analysis is effective for evaluating steroid receptors. The aim of this study was to determine concordance between ER and PR assessed by ICA on FS and paraffin sections (PS) both evaluated by image analysis. There were 115 breast carcinomas selected. For all cases, ER and PR determination was performed on FS and PS. Computer-assisted image analysis was performed using CAS 200. Results were expressed as percent positive area of neoplastic nuclei compared with total nuclear area of the examined neoplastic cells. Good correlation was demonstrated for both ER (r=0.759; concordance=83.4%) and PR (r=0.800; concordance=87.8%). The unexpected relatively low concordance for ER led to further investigations. We divided the 115 cases in two groups. The first group included specimens from our hospital; the second group specimens from suburban hospitals. In the first group there was better correlation for both ER (r=0.897) and PR (r=0.915) with a concordance of 91.5% and 93.6%, respectively. In the second group, correlation was worse for both ER (r=0.724) and PR (r=0.708), with a concordance of 77.9% and 83.9% respectively. From analysis of discordant cases we conclude that reduction in correlation and concordance with increased false negative cases in group 2 are probably due to delayed fixation. Our data suggest that ICA with automated image analysis is efficient in evaluating ER and PR on paraffin section only when the tumour samples are correctly fixed.
Cytometry, 1996
Image cytometric analysis of DNA ploidy status of 40 fresh primary breast carcinomas was performe... more Image cytometric analysis of DNA ploidy status of 40 fresh primary breast carcinomas was performed in a comparative study on cytologic preparations stained directly by the Feulgen method and smears from the same tumors Feulgen-stained after Papanicolaou staining. There was a 0.82 overall concordance in diploid and aneuploid tumor classification and a good correlation (r = 0.736, P < 0.001) between the DNA indices determined by the two methods. Discordances are probably due to tumor heterogeneity. This study demonstrates that image cytometric DNA analysis on previously routine-stained cytologic preparations is feasible and reliable for pretreatment DNA analysis and suggests potential applications in retrospective studies with cytologic material from archives.
Combustion Science and Technology, 2004
Thermokinetic temperature oscillations related to oxidation of small hydrocarbons have not been e... more Thermokinetic temperature oscillations related to oxidation of small hydrocarbons have not been extensively studied yet, because they occur in a temperature and pressure range not relevant for practical applications. Exploitation of new combustion methodologies such as Mild Combustion also indicated such a phenomenology in small-hydrocarbons oxidation. In this paper, experimental characterization of dynamic behavior occurring in methane mild combustion in
Experimental Thermal and Fluid Science, 2007
The reduction of pollutants emission, such as NOx and soot, can be achieved by lowering and contr... more The reduction of pollutants emission, such as NOx and soot, can be achieved by lowering and controlling the adiabatic temperature of the system. Mild Combustion processes employ great amounts of diluents and high inlet temperatures of reactants. The first aspect guarantees a high heat capacity of the system, hence lower working temperatures with respect to a traditional oxidation process; the latter feature comes out from the necessity to sustain the oxidation process with no-flammable mixtures working with so high dilution degree. This new kind of combustion presents several features that deserve a systematic study.Previous experimental works carried out in a jet stirred flow reactor showed a complex dynamic behavior of methane Mild Combustion. In practical applications, such instabilities do not allow to control the working temperature; thus they lower the efficiency of the combustion processes. In this paper, the effect of hydrogen addition to the methane combustion in Mild conditions was studied, with particular focus on the dynamic behavior detected in the past.The experimental results showed that the higher the inlet hydrogen content, the higher the increase of the system reactivity and a more significant reduction of the area in the Tin–C/O plane where thermo-kinetics oscillations were observed. However, hydrogen addition did not affect significantly the typology of oscillations. Furthermore, it was observed that in the Tin–C/O plane the dynamic region shifts towards lower temperatures as well as the irregular oscillation region extends as the hydrogen concentration increases.The experimental Tin–C/O maps were then compared with the numerical ones, obtained with different kinetic mechanisms available in the literature.An overall good agreement was found between experimental and numerical data. The evolution of the oscillations region and the increase of reactivity due to the hydrogen addition were predicted quite well.
Atomization and Sprays, 1999
Atomization and Sprays, 1991
ABSTRACT
Lung Cancer, 2003
The aim of this study was to evaluate the impact of Bcl-2, retinoblastoma (Rb) and p53 proteins o... more The aim of this study was to evaluate the impact of Bcl-2, retinoblastoma (Rb) and p53 proteins on overall survival of 102 patients with locally advanced and metastatic NSCLC who underwent cisplatin-based chemotherapy. Paraffin-embedded bronchial biopsy and fine-needle biopsy specimens were evaluated by an immunostaining method. Median age of analyzed patients was 61 years. Male/female ratio was 88/14. There were 10 (10%) patients with stage IIIA, 37 (36%) with stage IIIB and 55 (54%) with stage IV NSCLC. Only 15 (15%) tumor specimens had no detectable alterations for analyzed factors. Forty-six samples (45%) had positive immunostaining for p53, 61 (60%) had negative immunostaining for Rb and 8 (8%) had positive immunostaining for Bcl-2. Median and 5-year survival of analyzed population was 12 months and 6%, respectively. In univariate analysis Bcl-2 overexpression, stage (III versus IV) and normal lactate dehydrogenase (LDH) serum levels were associated with better overall survival (P<0.02, 0.001 and 0.03). In multivariate analysis, only stage was identified as an independent predictive factor. High frequency of Rb and Bcl-2 loss was detected in patients with advanced NSCLC. P53, Rb and Bcl-2 have not been shown to be independent predictors of survival even if Bcl-2 might have a particular relevance in patients with advanced NSCLC and should be better explored in this setting.
Clean Air: International Journal on Energy for a Clean Environment, 2006
Breast, 2001
DNA ploidy image analysis in breast carcinomas has occasionally revealed cases with a diploid DNA... more DNA ploidy image analysis in breast carcinomas has occasionally revealed cases with a diploid DNA content but with a single hypertetraploid element, the so-called single cell aneuploidy (SCA). To identify the biologic significance of this little known phenomenon, we selected 40 cases with SCA from a series of 599 consecutive operable breast carcinomas.The clinical, pathological and biological characteristics of SCA cases were compared with those of a control group of 40 pure diploid breast carcinomas. Hormonal receptor status, proliferative indexes (Ki-67) and p53 overexpression were determined immunohistochemically and quantitatively evaluated by image analysis. The overexpression of c-erbB-2 was determined semiquantitatively.SCA was observed in 6.6% of cases (40 of 599) and in 17% of otherwise diploid cases (40 of 236). Breast cancers with SCA occur in younger women (mean age 54.75 y vs 61.12 y, P<0.05), are smaller (mean diameter 20.00 vs 21.62 mm), less differentiated (percentage of G3 cases 13.2 vs 2.9), more frequently hormone independent (ER positivity 70.0 vs 77.5%; PgR positivity 57.5 vs 77.5%) and have a greater cell proliferative activity (mean S-phase: 4.6 vs 2.8, P<0.05), (percentage of Ki-67 immunostaining: 24.1 vs 19.7%). There is also more overexpression of c-erbB-2 and P53, particularly in pT1 cases in which the percentage of c-erbB-2 positive cells is 54 vs 32 (P value is not significant) and the percentage of p53 is 29 vs 4 (P<0.05).According to these results SCA may be a reliable marker of genetic instability and of greater biologic aggressiveness. Image cytometry of DNA content may be a cost effective means of identifying breast cancer patients with an increased risk of tumour recurrences despite otherwise favourable prognostic parameters.
Cancer Letters, 2005
For breast cancer management biopathologic profile and particularly the expression of estrogen re... more For breast cancer management biopathologic profile and particularly the expression of estrogen receptor (ER) and progesterone receptor (PR) is considered essential. In advanced cases, core biopsy results are the only data available. To evaluate reliability of data, results of ER, PR, MIB1, p53 and c-erbB2 on core biopsy were compared with those on surgical specimens. Results showed a statistically significant concordance for ER and PR in pT1 but not in pT2 tumors, possibly due to breast cancer heterogeneity. MIB1 results were worse with no significant concordance even for pT1 group. There was statistically significant concordance in pT1 and pT2 groups for p53 and c-erbB 2, probably due to the high number of negative cases for these markers. We recommend more core biopsies for larger tumors since core biopsy has a high probability for giving unreliable data in these cases. In conclusion, this study showed that core biopsy has a high probability for not very reliable data in bigger tumors where the results obtained might be the only data available. A higher number of core biopsy is recommended in those cases.
International Journal of Surgical Pathology, 2004
Primary cutaneous leiomyosarcomas are rare tumors, few series being reported in the current liter... more Primary cutaneous leiomyosarcomas are rare tumors, few series being reported in the current literature. A retrospective study of 7 cases was undertaken to understand the clinicopathological characteristics of these neoplasms and some of their molecular mutations. Histologically, a well-differentiated proliferation of cells of smooth muscle derivation was evident in all cases. The number of mitoses was considered the most important criterion of malignancy (more than 2 for 10 HPF). Smooth muscle actin, desmin, and vimentin were positive in all cases. Immunohistochemical analysis also revealed a positivity for p53 in 3 cases and no reaction for retinoblastoma protein. Research for Epstein-Barr virus was negative in all cases. Three patients developed local recurrences owing to incomplete surgical excision. Recurrent tumors were more atypical and located deeper. No distant metastases were observed. Our results emphasize that cutaneous leiomyosarcomas have an indolent biological course if treated by surgical excision with wide margins. Molecular abnormalities involving tumor suppressor genes are probably involved.
Clean Air: International Journal on Energy for a Clean Environment, 2003
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Papers by Antonio Cavaliere