Mixture polarization in inter-rater agreement analysis: a Bayesian nonparametric index

In several observational contexts where different raters evaluate a set of items, it is common to assume that all raters draw their scores from the same underlying distribution. However, a plenty of scientific works have evidenced the relevance of individual variability in different type of rating tasks. To address this issue the intra-class correlation coefficient (ICC) has been used as a measure of variability among raters within the Hierarchical Linear Models approach. A common distributional assumption in this setting is to specify hierarchical effects as independent and identically distributed from a normal with the mean parameter fixed to zero and unknown variance. The present work aims to overcome this strong assumption in the inter-rater agreement estimation by placing a Dirichlet Process Mixture over the hierarchical effects' prior distribution. A new nonparametric index $\lambda$ is proposed to quantify raters polarization in presence of group heterogeneity. The model is applied on a set of simulated experiments and real world data. Possible future directions are discussed

Demineralizing action of EGTA in endodontics.

The demineralization of dentin obtained by treatment with a chelating agent ethylene diamminotetracetic acid (EDTA) or ethylene glycol-bis(β-aminoethyl ether)-N-tetraacetic acid (EGTA), is a dynamic process involving chelation and solubilization. The actions of the EDTA and EGTA on dentin are influenced by the pH. Increasing mM concentrations of EDTA or EGTA the equivalent pH decreases in a similar slope to 80 mM chelator concentration. Increasing the chelator concentration different data were obtained: with EGTA the pH decreases slightly while with EDTA goes back up to the initial values. After 80 mM, EDTA reduces the activity on the dentin, and EGTA continues to work at higher concentrations. We demonstrated that EGTA solubilized more of 60% of dentin while EDTA gives about 20% at the maximal of the solubility

Effect of pre-operatory low-level laser therapy on pain, swelling, and trismus associated with third-molar surgery

The extraction of impacted third molars is commonly associated to pain, edema, trismus, limited jaw opening and movements. The aim of this retrospective study is to verify if pre-surgical low-level laser therapy (LLLT) associated with the extraction of impacted lower third molars could add benefits to the postoperative symptoms respect LLLT performed only after surgery. Data from 45 patients subjected to a surgical extraction of lower third molars were pooled and divided into three groups. Patients that received only routine management were inserted in the control group. Group 1, were patients that received LLLT immediately after surgery and at 24 hours. In group 2 were included patients treated with LLLT immediately before the extraction and immediately after the end of the procedure. Data were analyzed using linear regression and descriptive statistics. Both laser-treated groups were characterized by minor events of post-surgery complications of pain, edema, trismus. The use of NSAIDs in the first 24 hours was significantly inferior in Group 2. Pre-surgical LLLT treatment seems to increase the analgesic effect of LLLT. However, trismus and edema were reduced in both laser treated groups, independently from the period of irradiation

Recycled Mortars with C&D Waste

Nowadays an environmental problem that cannot be underestimated is the increasing amount of waste of different nature. Certainly, an environmental friendly solution is to use waste directly or indirectly in the production of concrete or mortar, which are the most used building materials in the world. In the production of coarse recycled aggregates (RA), the fine fraction, also called recycled sand (RS), is involuntarily produced and it represents a large amount of the weight of the crushed C&D waste. Generally, the problem of fine fraction has not been much analysed until now. For this reason, in this work, an innovative mortar mix design for using recycled sand from C&D has been analysed, by partial replacement of standardized sand (SS) with recycled sand (RS) or washed recycled sand (RSW) and by using a fixed w/c ratio equal to 0.5. The main aim of this research has been to investigate if washing and sieving of recycled aggregates can improve the quality of the recycled aggregate. Analyses allowed concluding that the quality of the recycled aggregate could be improved by washing and sieving of recycled aggregates and that in any case the bending strength and the fracture energy increase or decrease simultaneously

Microbiological and biochemical effectiveness of an antiseptic gel on the bacterial contamination of the inner space of dental implants: a 3-month human longitudinal study.

Microbial penetration inside the implant's internal cavity produces a bacterial reservoir that is associated with an area of inflamed connective tissue facing the fixture-abutment junction. The aim of this clinical trial is to evaluate the effectiveness of a 1% chlorhexidine gel on the internal bacterial contamination of implants with screw-retained abutments and on the level of AST secreted in peri-implant crevicular fluid. Twenty-five patients (aged 29 to 58 years) each received one implant. Three months after the end of the restorative treatment, and immediately after a clinical and radiographic examination and the abutment removal, microbiological samples were obtained from the internal part of each fixture and biochemical samples were collected by peri-implant sulci. The patients were then divided into two groups: the control (CG; n=10) and test (TG; n=15) groups. The CG had the abutment screwed into place and the crown cemented without any further intervention. In contrast, before the abutment placement and screw tightening, the TG had the internal part of the fixture filled with a 1% chlorhexidine gel. Three months later, the same clinical, microbiological and biochemical procedures were repeated in both groups. Total bacterial count, specific pathogens and AST activity were detected. The clinical parameters remained stable throughout the study. From baseline to the 3-month examination, the total bacterial counts underwent a significant reduction only in the TG. In contrast, the AST activity showed a significant increase in the CG. The administration of a 1% chlorhexidine gel appears to be an effective method for the reduction of bacterial colonization of the implant cavity and for safeguarding the health status of peri-implant tissue over a 3-month administration period

The effects of enzalutamide and abiraterone on skeletal related events and bone radiological progression free survival in castration resistant prostate cancer patients: An indirect comparison of randomized controlled trials

Two new drugs, the CYP17 inhibitor abiraterone acetate and the androgen receptor (AR) antagonist enzalutamide, have recently shown to prolong OS prior chemotherapy or in docetaxel treated mCRPC patients, using steroidal therapy or placebo as control group. Updated analyses underlined the role of these new agents on two prostate-specific endpoints as radiographic progression-free survival (rPFS) and time to first skeletal-related event (tSRE). On the basis of these reports, we made an indirect comparison between abiraterone and enzalutamide. We obtained a clinically but not significant difference favouring enzalutamide over abiraterone in terms of rPFS (HR 0.48, 95% CI 0.22â1.02). No significant difference was shown in term of tSRE (HR 0.99, 95% CI 0.83â1.17). In conclusion, abiraterone and enzalutamide have both demonstrated to significantly delay the bone progression resulting in similar improvements in bone-related endpoints in patients with mCRPC

Pegaso: an ultra-light long duration stratospheric

Launched from the Mario Zuccelli Station (Baia Terra Nova) in Antarctica during the 2005/06 austral summer, the PEGASO-D payload lifted into the stratospheric anticyclone over the southern polar region. This effort marks the first Long Duration Scientific payload to be launched from this location and is the fourth such payload launched in the polar regions. Performing in the framework of the NOBILE/AMUNDSEN collaborative LDB development between ASI-ARR. The Italian Institute of Geophysics and Volcanology (INGV), with the sponsorship of the Italian Antarctic Program (PNRA) and the Italian Space Agency (ASI),designed and built the Ultra-Light system together with three Universities in Italy. The Pegaso program has been created to investigate the Earth magnetic field and provide a precursor series of small payload launches for the bigger LDB program such as OLIMPO, BOOMERanG and BArSPOrt through this collaboration between ASI and ARR. The Italian scientific community, aware of the big advantages that LDB balloons can offer to their experiments, proposed to extend the LDB program to Southern polar regions, besides performing launches from the newly initiated Nobile/Amundsen Stratospheric Balloon Center in Svalbard, Norway.Three PEGASO (Polar Explorer for Geomagnetics And other Scientific Observations) payloads have been launched from the Svalbard (No) in collaboration with Andoya Rocket Range, ASI and ISTAR (Operations and logistics) during the past two northern summers. These stratospheric (altitude m.35000) small 10kmc balloons have floated in the stratosphere between 14 to 39 days measuring the magnetic field of polar regions, by means of a 3-axys-fluxgate magnetometer, during a three year campaign. The study of the magnetic field and its variations is done through permanent observatories. They provide us with high quality data but their spatial distribution is not quite regular, specially in Antarctica due to logistic difficulties. The coverage is improved through marine and aeromagnetic surveys, and also through satellite missions. There exists nevertheless a gap in the wavelengths of the magnetic field represented by these kind of measurements. Satellite data are too far away from Earth's surface to individuate wavelengths lower than 1000 km, and near-ground sur- veys are not able to represent wavelengths longer than the dimensions of the surveyed area. Moreover, there is a region empty of data around the geographical pole for the satellite measurements. The size of these gaps depends on the orbital parameters, but it can reach up to 10 degrees around the pole. PEGASO allows to bridge this gap in the measurements of the magnetic field. Surveys carried out at 35 km height allow the study of crustal anomalies in the range between, we can say, 60 and 1000 km. Taking into account that pathfinders (smaller non-recoverable balloon systems) are usually sent to explore the atmospheric currents, the use of PEGASO as pathfinder allows us to obtain all these results at a very affordable cost. The PEGASO payload was also developed as a single source system integrating science, housekeeping and operational control of the entire balloon borne configuration.Satellite telemetry sent the scientific (magnetometric) data, house-keeping (temperature, solar panel voltage and current, altitude and time) and telecommand (four ballast, two parachute release system, system reset), and powered the terminate system. Data flows through the IRIDIUM telephone service. The onboard systems were kept inside a vessel (white painted and pressurizzed vessel due to power dissipation) except for external flexible solar panels and magnetometer, attached to an external boom. Two redundant tracking systems have been used: a first GPS was integrated inside the on-board telemetry system, necessary to reconstruct position and time of scientific data, while an independent GPS-ARGOS system gave the balloon trajectory, including its descent. Continuous trajectory predictions were made during the missions; they have been necessary, in particular, for the flight safety requirements of the northern hemisphere. The evaluation of the statistical error is proposed. The PEGASO payload was developed to be a light, cost effective way to explore the potential of Ultra-Light Long Duration Ballooning for science as well as an introduction to the earth-space possibilities for students.PublishedBeijing, China1A. Geomagnetismo e Paleomagnetism