6,204 research outputs found

    DEFINITION OF NOVEL HEALTH AND AIR POLLUTION INDEX BASED ON SHORT TERM EXPOSURE AND AIR CONCENTRATION LEVELS

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    Health impact assessment has become important in the development of air quality policies and in finding the relationships between pollutants concentration and health effects. In our work we presented a novel index able to evaluate the effects on the human exposure caused by ambient air pollution in urban areas. The index is able to link both health risk factors and pollutants levels. The indexes is of additive type and is composed by two terms: the former is based on pollutants concentration and is connected with EPA air quality index (AQI), while the latter is composed by an adimensional term based on the exposure levels. We tested the methodology using PM10 as studied pollutants. The spatial and temporal variation of its health impact was evaluated by means of index maps applying the above methodology in the city of Rome during three selected episodes. Our study shows index maps for all episodes linked to population and to pollutants

    Correlation between Microleakage and Tubules Penetration of an Endodontic Sealer

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    Objective: The aim of the study was to verify the existence of a correlation between fluid filtration and tubular penetration of an endodontic sealer. Methods: Ten pairs of maxillary incisors with a single root canal, circular cross-section, similar sizes and dimensions were selected from a collection. Teeth from each pair were randomly divided in 2 groups. All canals were instrumented using NiTi WaveOne Primary instrument (#25) (Dentsply, Maillefer). In the group 1 all canals were irrigated with 1 mL of 5,25% NaOCl for 30s (Ogna, Muggi\uf2, Italy), followed by 0.5 mL of 10% EDTA for 30 s (Ogna). In the group 2 it\u2019s used the same protocol but without the EDTA. A final irrigation of 2.0 mL 5,25% NaOCl for 3m was performed. Root filling was performed with Thermafil-obturators (Dentsply Tulsa, Tulsa, OK) with TopSeal (Dentsply, Maillefer) mixed with 0.1 wt% alizarin to evaluate the penetration depth of the sealer into tubules with confocal microscope (Leica, Wetzlar, Germany). Microleakage i.e. the volume of a calcein solution infiltrated into the root canal and tubules were evaluated using a digital fluid flow-meter and a confocal microscope. Results: Confocal microscopy showed a penetration of the sealer into tubules in group 1 of approx. 370 \u3bcm at 3 mm from the apex and 630 \u3bcm at 5 mm while in group 2 of approx. 22 \u3bcm at 3 mm and 37 \u3bcm at 5 mm from the apex. The volume of the infiltrated fluid was 0.353 x 10-4 mm3 for group 1 and 0.397 x 10-4 mm3 for group 2. The data of calcein penetration into the root canal were in agreement with the fluid filtration results. Conclusion: A correlation seems to be present between sealer penetration into dentinal tubules and sealability of Thermafil-obturators and TopSeal in root canal shaped with WaveOne Primary file

    Arginine-Based Toothpaste Induces Calcium-Phosphates Deposits on Dentin Surface and Tubules

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    Objective: To test the ability of a calcium carbonate-containing toothpaste for dentinal hypersensitivity to occlude the exposed open tubules of dentin surface. Method: Dentine slices (0.9±0.1 thick) and crown segments (1.5±0.3 cm thick) from human third molars were used. Elmex Sensitive Professional toothpaste (GABA Int AG, Therwill, Switzerland) containing as main active ingredients arginine (8%), sodium monofluorophosphate (1450 ppm Fˉ) and calcium carbonate, was applied (3 min) on coronal dentin surface. Fluid flow/permeation through the dentin thickness (i.e. permeability or hydraulic conductance, Lp in microliters/min) was evaluated using a digital fluid flow-meter after smear layer formation, after EDTA treatment, after Elmex toothpaste treatment (t=0) and after soaking for 1, 7, 28 days in simulated body fluid (HBSS). Tubules occlusion, elemental analysis and mineral content were studied by ESEM-EDX. Toothpaste penetration inside dentinal tubules was analyzed by laser confocal microscopy using calcein as tracer. Result: Lp of EDTA-treated dentin significantly decreased after treatment with Elmex toothpaste (-73,32% at t=0) and after soaking in HBSS the Lp values further decreased (-77,69% at 24h, -78,18% at 7d, -83,01% at 28d). After 24h and 7d in HBSS, ESEM on Elmex-treated dentin showed the presence of precipitates on dentin surface and in the dentinal tubules; EDX revealed N (from arginine) and F (from monofluorophosphate) of the toothpaste. Lp remained significantly lower (-78,18%) than EDTA- treated control dentin. After 28d in HBSS, a calcium phosphate layer was detected on dentin surface so tubules were not visible. EDX detected F and no N. No CaP deposits were found on EDTA-treated dentin soaked in HBSS. Confocal microscopy showed an average penetration depth of the toothpaste into the dentinal tubules of ~85 microns. Conclusion: Elmex sensitive toothpaste can reduce the fluid movement into the exposed dentinal tubules and favour the formation of calcium phosphate minerals

    Physico-mechanical properties of two different heat treated Nickel-Titanium instruments: in-vitro study

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    Aim: This study aimed to define physico-mechanical properties of recently introduced thermally treated Edge Taper Platinum (ET Platinum) Nickel-Titanium (NiTi) instruments compared to conventional NiTi Edge Taper (ET) to disclose improvements obtained by heat-treatments. Methods: ET and ET Platinum instruments (n=30/each) were rotated until fracture in a stainless-steel canal with 90°curvature angle and 5mm curvature radius. Time to fracture (TtF) and number of cycles to fracture (NCF) were calculated and results were analyzed using Mann-Whitney test (p=0.05). Fractured instruments underwent fractographic analysis under Field-Emission-Gun Scanning Electron Microscope (FEG-SEM). Superficial features of additional new ET and ET Platinum instruments were analyzed under SEM at increasing magnification with standardized angulations and positions. After inspection, ET and ET Platinum instruments were used in extracted teeth to shape 4 straight canals each to simulate clinical conditions and re-evaluated under SEM at the same points to detect superficial wear features. ET and ET Platinum brand new instruments were examined by differential scanning calorimetry (DSC) to assess transformation temperatures. Results: Cyclic fatigue test showed a significant increase of fatigue resistance on ET Platinum compared to ET instruments (p=0.05). Fractographic analysis demonstrated a pattern of fatigue propagation on both instruments. SEM analysis on brand new instruments revealed a more regular surface of ET Platinum compared with ET and both instruments appeared with minimal alterations after the simulated clinical use. DSC analysis demonstrated higher amounts of martensite at 37°C in ET Platinum compared to ET instruments. Conclusions: ET Platinum instruments displayed an improved mechanical behavior, possibly related to modified phase transformation temperatures induced by thermal treatment of the alloy during manufacturing process. These results suggest a safe use in clinical conditions

    Let-7g and miR-21 expression in non-small cell lung cancer: correlation with clinicopathological and molecular features

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    MicroRNAs (miRNAs) play a key role in cancer pathogenesis and are involved in several human cancers, including non-small cell lung cancer (NSCLC). This study evaluated Let-7g and miR-21 expression by quantitative real-time PCR in 80 NSCLC patients and correlated the results with their main clinicopathological and molecular features. MiR-21 expression was significantly higher in NSCLC tissues compared to non-cancer lung tissues (p<0.0001), while no significant changes in Let-7g expression were observed between the tumor and normal lung tissues. Target prediction analysis led to the identification of 26 miR-21 and 24 Let-7g putative target genes that play important roles in cancer pathogenesis and progression. No significant association was observed between the analysed miRNAs and the main clinicopathological or molecular characteristics of the NSCLC patients, although both miRNAs were downregulated in squamous cell carcinomas compared to adenocarcinomas. Noteworthy, we observed a significant association between low Let-7g expression and metastatic lymph nodes at diagnosis (p=0.046), as well as between high miR-21 expression and K-Ras mutations (p=0.0003). Survival analysis did not show any significant correlation between prognosis and the analysed miRNAs, although the patients with a high Let-7g and miR-21 expression showed a significantly lower short-term progression-free survival (p=0.01 and p=0.0003, respectively) and overall survival (p=0.023 and p=0.0045, respectively). In conclusion, we showed that Let-7g and miR-21 expression was deregulated in NSCLC and we demonstrated a strong relationship between miR-21 overexpression and K-Ras mutations. Our data indicate that Let-7g and miR-21 profiling combined with the determination of K-Ras mutational status may be considered a useful biomarker for a more effective molecular characterization and clinical management of NSCLC patients

    Update On the Status of the FLUKA Monte Carlo Transport Code*

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    The FLUKA Monte Carlo transport code is a well-known simulation tool in High Energy Physics. FLUKA is a dynamic tool in the sense that it is being continually updated and improved by the authors. We review the progress achieved since the last CHEP Conference on the physics models, some technical improvements to the code and some recent applications. From the point of view of the physics, improvements have been made with the extension of PEANUT to higher energies for p, n, pi, pbar/nbar and for nbars down to the lowest energies, the addition of the online capability to evolve radioactive products and get subsequent dose rates, upgrading of the treatment of EM interactions with the elimination of the need to separately prepare preprocessed files. A new coherent photon scattering model, an updated treatment of the photo-electric effect, an improved pair production model, new photon cross sections from the LLNL Cullen database have been implemented. In the field of nucleus-- nucleus interactions the electromagnetic dissociation of heavy ions has been added along with the extension of the interaction models for some nuclide pairs to energies below 100 MeV/A using the BME approach, as well as the development of an improved QMD model for intermediate energies. Both DPMJET 2.53 and 3 remain available along with rQMD 2.4 for heavy ion interactions above 100 MeV/A. Technical improvements include the ability to use parentheses in setting up the combinatorial geometry, the introduction of pre-processor directives in the input stream. a new random number generator with full 64 bit randomness, new routines for mathematical special functions (adapted from SLATEC). Finally, work is progressing on the deployment of a user-friendly GUI input interface as well as a CAD-like geometry creation and visualization tool. On the application front, FLUKA has been used to extensively evaluate the potential space radiation effects on astronauts for future deep space missions, the activation dose for beam target areas, dose calculations for radiation therapy as well as being adapted for use in the simulation of events in the ALICE detector at the LHC

    Has VZV epidemiology changed in Italy? Results of a seroprevalence study

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    The aim of the study was to evaluate if and how varicella prevalence has changed in Italy. In particular a seroprevalence study was performed, comparing it to similar surveys conducted in pre-immunization era. During 2013–2014, sera obtained from blood samples taken for diagnostic purposes or routine investigations were collected in collaboration with at least one laboratory/center for each region, following the approval of the Ethics Committee. Data were stratified by sex and age. All samples were processed in a national reference laboratory by an immunoassay with high sensitivity and specificity. Statutory notifications, national hospital discharge database and mortality data related to VZV infection were analyzed as well. A total of 3707 sera were collected and tested. In the studied period both incidence and hospitalization rates decreased and about 5 deaths per year have been registered. The seroprevalence decreased in the first year of life in subjects passively protected by their mother, followed by an increase in the following age classes. The overall antibody prevalence was 84%. The comparison with surveys conducted with the same methodology in 1996–1997 and 2003–2004 showed significant differences in age groups 1–19 y. The study confirms that in Italy VZV infection typically occurs in children. The impact of varicella on Italian population is changing. The comparison between studies performed in different periods shows a significant increase of seropositivity in age class 1–4 years, expression of vaccine interventions already adopted in some regions

    Study of Upsilon(3S,2S) -> eta Upsilon(1S) and Upsilon(3S,2S) -> pi+pi- Upsilon(1S) hadronic trasitions

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    We study the Upsilon(3S,2S)->eta Upsilon(1S) and Upsilon(3S,2S)->pi+pi- Upsilon(1S) transitions with 122 million Upsilon(3S) and 100 million Upsilon(2S) mesons collected by the BaBar detector at the PEP-II asymmetric energy e+e- collider. We measure B[Upsilon(2S)->eta Upsilon(1S)]=(2.39+/-0.31(stat.)+/-0.14(syst.))10^-4 and Gamma[Upsilon(2S)->eta Upsilon(1S)]/Gamma[Upsilon(2S)-> pi+pi- Upsilon(1S)]=(1.35+/-0.17(stat.)+/-0.08(syst.))10^-3. We find no evidence for Upsilon(3S)->eta Upsilon(1S) and obtain B[Upsilon(3S)->eta Upsilon(1S)]<1.0 10^-4 and Gamma[Upsilon(3S)->eta Upsilon(1S)]/Gamma[Upsilon(3S)->pi+pi- Upsilon(1S)]<2.3 10^-3 as upper limits at the 90% confidence level. We also provide improved measurements of the Upsilon(2S) - Upsilon(1S) and Upsilon(3S) - Upsilon(1S) mass differences, 562.170+/-0.007(stat.)+/-0.088(syst.) MeV/c^2 and 893.813+/-0.015(stat.)+/-0.107(syst.) MeV/c^2 respectively.Comment: 8 pages, 16 encapsulated postscript figures, submitted to Phys.Rev.

    Evidence for the Ρ_b(1S) Meson in Radiative μ(2S) Decay

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    We have performed a search for the η_b(1S) meson in the radiative decay of the Υ(2S) resonance using a sample of 91.6 × 10^6 Υ(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at E_γ = 609.3^(+4.6)_(-4.5)(stat)±1.9(syst) MeV, corresponding to an η_b(1S) mass of 9394.2^(+4.8)_(-4.9)(stat) ± 2.0(syst) MeV/c^2. The branching fraction for the decay Υ(2S) → γη_b(1S) is determined to be [3.9 ± 1.1(stat)^(+1.1)_(-0.9)(syst)] × 10^(-4). We find the ratio of branching fractions B[Υ(2S) → γη_b(1S)]/B[Υ(3S) → γη_b(1S)]= 0.82 ± 0.24(stat)^(+0.20)_(-0.19)(syst)

    Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

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    A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE
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