Effect of different dental articulating papers on SEMG activity during maximum clenching

This study evaluated the influence of two different occlusal indicators (articulating papers of 40\u3bcm and 200\u3bcm) on muscular activity of the temporalis anterior (TA) and superficial masseter (MS) during maximum voluntary clenches (MVC), using surface electromyography (SEMG). It was hypothesized that an articulating paper positioned between dental arches during MVC elicits a different muscular activity compared with the occlusion on natural dentition (without the occlusal indicator). 30 healthy adult subjects with a complete, natural dentition were recruited; SEMG activity was recorded in the following experimental conditions: MVC with cotton rolls for standardization purposes; MVC on natural dentition; MVC onto the 40 \u3bcm or 200\u3bcm paper indicator positioned on right or left side of the dental arch. Percentage Overlapping Coefficient (POC; separate values obtained for TA and MS), antero-posterior coefficient (APC) and total muscle activities (IMP) were the analyzed SEMG parameters. The use of an occlusal indicator statistically changed POC_TA, POC_MS and IMP median values (p 0.05). In conclusion, the examined articulating papers affected two specific SEMG parameters (POC and IMP); the recorded muscular activity with the occlusal indicator varied regardless left or right side positioning, and independently from tested paper thicknesses

Mechanical Properties of Elastomeric Imperssion Materials : An in vitro comparison

Purpose. Although new elastomeric impression materials have been introduced into the market, there are still insufficient data about their mechanical features. The tensile properties of 17 hydrophilic impression materials with different consistencies were compared. Materials and Methods. 12 vinylpolysiloxane, 2 polyether, and 3 hybrid vinylpolyether silicone-based impression materials were tested. For each material, 10 dumbbell-shaped specimens were fabricated (n=10), according to the ISO 37:2005 specifications, and loaded in tension until failure. Mean values for tensile strength, yield strength, strain at break, and strain at yield point were calculated. Data were statistically analyzed using one-way ANOVA and Tukey's tests (\u3b1=0.05). Results. Vinylpolysiloxanes consistently showed higher tensile strength values than polyethers. Heavy-body materials showed higher tensile strength than the light bodies from the same manufacturer. Among the light bodies, the highest yield strength was achieved by the hybrid vinylpolyether silicone (2.70 MPa). Polyethers showed the lowest tensile (1.44 MPa) and yield (0.94 MPa) strengths, regardless of the viscosity. Conclusion. The choice of an impression material should be based on the specific physical behavior of the elastomer. The light-body vinylpolyether silicone showed high tensile strength, yield strength, and adequate strain at yield/brake; those features might help to reduce tearing phenomena in the thin interproximal and crevicular areas

Thermal monitoring of hydrothermal activity by permanent infrared automatic stations: Results obtained at Solfatara di Pozzuoli, Campi Flegrei (Italy)

A permanent automatic infrared (IR) station was installed at Solfatara crater, the most active zone of Campi Flegrei caldera. After a positive in situ calibration of the IR camera, we analyze 2175 thermal IR images of the same scene from 2004 to 2007. The scene includes a portion of the steam heated hot soils of Solfatara. The experiment was initiated to detect and quantify temperature changes of the shallow thermal structure of a quiescent volcano such as Solfatara over long periods. Ambient temperature results as the main parameter affecting IR temperatures while air humidity and rain control image quality. A geometric correction of the images was necessary to remove the effects of slow movement of the camera. After a suitable correction the images give a reliable and detailed picture of the temperature changes, over the period October 2004 – January 2007, which suggests origin of the changes were linked to anthropogenic activity, vegetation growth and to the increase of the flux of hydrothermal fluids in the area of the hottest fumaroles. Two positive temperature anomalies were registered after the occurrence of two seismic swarms which affected the hydrothermal system of Solfatara in October 2005 and October 2006. It is worth noting that these signs were detected in a system characterized by a low level of activity with respect to systems affected by real volcanic crisis where more spectacular results will be expected. Results of the experiment show that this kind of monitoring system can be a suitable tool for volcanic surveillance

Cyclic behaviour of stone and brick masonry under uniaxial compressive loading

An experimental research concerning the uniaxial compressive behaviour of stone and brick specimens, as well as masonry prisms, is presented. Local sandstone and clay brick materials were used in order to obtain results representative with respect to local constructions. Aiming at a comprehensive material description, a set of displacementcontrolled experiments were carried out, both under monotonic and cyclic compressive loading. The procedure adopted for testing is described and the results are discussed, namely material brittleness, intrinsic variability, energy dissipation and stiffness degradation.Dans cet article une recherche expérimentale à propos du comportement en compression uniaxial de spécimens de pierre et de la brique, aussi bien que prismes de maçonnerie, est présenté. Grès et brique de l’argile locale ont été utilisés pour obtenir des résultats représentatifs en ce qui concerne les constructions locales. Avec l’objective de obtenir une description matérielle complète, un ensemble de tests contrôlé par déplacement a été emporté, sous chargement de compression monotonic et cyclique. La procédure adoptée pour tester est décrite et les résultats sont discutés, nommément la fragilité matérielle, variabilité intrinsèque des matériaux, dissipation d’énergie et déchéance de la raideur

Antiproliferative effect of colonic fermented phenolic compounds from jaboticaba (Myrciaria trunciflora) fruit peel in a 3D cell model of colorectal cancer

Jaboticaba is a Brazilian native berry described as a rich source of phenolic compounds (PC) with health promoting effects. PC from jaboticaba peel powder (JPP) have low intestinal bio-accessibility and are catabolized by gut microbiota. However, the biological implication of PCderived metabolites produced during JPP digestion remains unclear. This study aimed to evaluate the antiproliferative effects of colonic fermented JPP (FJPP) in a 3D model of colorectal cancer (CRC) composed by HT29 spheroids. JPP samples fermented with human feces during 0, 2, 8, 24 or 48 h were incubated (10,000 µg mL−1 ) with spheroids, and cell viability was assessed after 72 h. Chemometric analyses (cluster and principal component analyses) were used to identify the main compounds responsible for the bioactive effect. The antiproliferative effect of FJPP in the CRC 3D model was increased between 8 h and 24 h of incubation, and this effect was associated with HHDP-digalloylglucose isomer and dihydroxyphenyl-γ-valerolactone. At 48 h of fermentation, the antiproliferative effect of FJPP was negligible, indicating that the presence of urolithins did not improve the bioactivity of JPP. These findings provide relevant knowledge on the role of colonic microbiota fermentation to generate active phenolic metabolites from JPP with positive impact on CRC

A seismic array on Mt. Vesuvius

In November 1997 a seismic antenna (array) of short period seismometers was installed on the south-western flank of Mt. Vesuvius; aim of the experiment was to test the use of non-conventional devices for the seismic monitoring of this volcano. In 7 months local seismicity, regional earthquakes and samples of seismic noise were recorded by the array and organised in a data base. Local earthquakes and seismic noise have been analysed with array techniques to investigate the spectral, kinematic and polarization properties of the wavefield. Preliminary results show that the backazimuth of local earthquakes is oriented in the direction of the crater area. For some events, the source location has been constrained using a simplified back propagation in a 2-D velocity structure. The noise wavefield is characterized by the predominance of a sustained low frequency component (< 1Hz) whose source is located S-SE of the array. This low frequency signal has been interpreted as associated to the sea-loading in the gulf of Naples.Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio VesuvianoPublished1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveope

A seismic array on Mt. Vesuvius

In November 1997 a seismic antenna (array) of short period seismometers was installed on the south-western flank of Mt. Vesuvius; aim of the experiment was to test the use of non-conventional devices for the seismic monitoring of this volcano. In 7 months local seismicity, regional earthquakes and samples of seismic noise were recorded by the array and organised in a data base. Local earthquakes and seismic noise have been analysed with array techniques to investigate the spectral, kinematic and polarization properties of the wavefield. Preliminary results show that the backazimuth of local earthquakes is oriented in the direction of the crater area. For some events, the source location has been constrained using a simplified back propagation in a 2-D velocity structure. The noise wavefield is characterized by the predominance of a sustained low frequency component (< 1Hz) whose source is located S-SE of the array. This low frequency signal has been interpreted as associated to the sea-loading in the gulf of Naples

Restoration of photosystem II photochemistry and carbon assimilation and related changes in chlorophyll and protein contents during the rehydration of desiccated Xerophyta scabrida leaves

Recovery of photosynthesis in rehydrating desiccated leaves of the poikilochlorophyllous desiccation-tolerant plant Xerophyta scabrida was investigated. Detached leaves were remoistened under 12 h light/dark cycles for 96 h. Water, chlorophyll (Chl), and protein contents, Chl fluorescence, photosynthesis–CO2 concentration response, and the amount and activity of Rubisco were measured at intervals during the rehydration period. Leaf relative water contents reached 87% in 12 h and full turgor in 96 h. Chl synthesis was slower before than after 24 h, and Chla:Chlb ratios changed from 0.13 to 2.6 in 48 h. The maximum quantum efficiency recovered faster during rehydration than the photosystem II operating efficiency and the efficiency factor, which is known to depend mainly on the use of the electron transport chain products. From 24 h to 96 h of rehydration, net carbon fixation was Rubisco limited, rather than electron transport limited. Total Rubisco activity increased during rehydration more than the Rubisco protein content. Desiccated leaves contained, in a close to functional state, more than half the amount of the Rubisco protein present in rehydrated leaves. The results suggest that in X. scabrida leaves Rubisco adopts a special, protective conformation and recovers its activity during rehydration through modifications in redox status

Seismic Tomography Experiment at Italy's Stromboli Volcano

From 25 November to 2 December 2006, the first active seismic tomography experiment at Stromboli volcano was carried out with the cooperation of four Italian research institutions. Researchers on board the R/V Urania of the Italian National Council of Research (CNR), which was equipped with a battery of four 210- cubic- inch generated injection air guns (GI guns), fired more than 1500 offshore shots along profiles and rings around the volcano.DPC/INGV agreement 2004-2006Published269-2701.4. TTC - Sorveglianza sismologica delle aree vulcaniche attive1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani3.6. Fisica del vulcanismoN/A or not JCRreserve

The Stromboli geophysical experiment. Preliminary report on wide angle refraction seismics and morphobathymetry of Stromboli Island (Southern Tyrrhenian Sea, Italy) based on integrated offshore-onshore data acquisition (Cruise STR06 R/V URANIA)

Cruise STR06 on R/V Urania was performed in the framework of the ”INGV - DPC V2 - Monitoring and research activity at Stromboli and Panarea - Unit V2/03”, and resulted as a joint initiative between CNR (IAMC, Napoli and ISMAR, Bologna), INGV (Roma2, Osservatorio Vesuviano, Catania, Gibilmanna-CNT), University of Firenze and DPC, aiming to produce a seismic tomography of the Stromboli volcano, South Eastern Tyrrhenian Sea [Fig.1], and have insights into its 2-D structure and magma chambers. Cruise work plan was designed to extend at sea the existing Seismographic Network, complemented by several mobile stations, and to generate seismic shots by air-gun tuned array. 10 OBS were deployed around Stromboli, along the NE, SE and SW flanks of the volcano, according to (a) morphobathymetric analysis of available and newly produced DTMs, (b) modeling and (c) optimal lineaments with on-land recording stations. Seismic shots along radial and circle lines were obtained by a 4 GI-GUN 105+105 C.I. tuned array, while the absolute shot time was recorded at the resolution of ms. A request for ship time of R/V Uraniawas presented by IAMC, and a period of 7 days, including 2 day of transit was assigned to the project by CNR and scheduled for late November 2006. Cruise STR06 started in Naples 2006-11-27 and ended in Naples 2006-12-06. This paper reports the shipboard activities during the cruise STR06 on R/V Urania and some preliminary results regarding also the onshore activities carried out in order to perform the Stromboli geophysical experiment. A description of the ship, equipment and their usage is given thereinafter, along with details of the general settings, performances and some scientific and technical results.Istituto di Scienze Marine, ISMAR-CNR, BolognaPublished3.6. Fisica del vulcanismo1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveope