Analytical Validation of Two Assays for Equine Ceruloplasmin Ferroxidase Activity Assessment

: Ceruloplasmin (Cp) assessment in biological samples exploits the oxidase activity of this enzyme against several substrates, such as p-phenylenediamine (p-P), o-dianisidine (o-D) and, most recently, ammonium iron(II) sulfate (AIS). Once developed in humans, these assays are often used in veterinary medicine without appropriately optimizing in the animal species of interest. In this study, two assays using AIS and o-D as substrates have been compared and validated for Cp oxidase activity assessment in horse's plasma. The optimization of the assays was performed mainly by varying the buffer pH as well as the buffer and the substrate molar concentration. Under the best analytical conditions obtained, the horse blood serum samples were treated with sodium azide, a potent Cp inhibitor. In the o-D assay, 500 µM sodium azide treatment completely inhibits the enzymatic activity of Cp, whereas, using the AIS assay, a residual analytical signal was still present even at the highest (2000 µM) sodium azide concentration. Even though the analytical values obtained from these methods are well correlated, the enzymatic activity values significantly differ when expressed in Units L-1. A disagreement between these assays has also been detected with the Bland-Altman plot, showing a progressive discrepancy between methods with increasing analytical values

Update of the Italian Seismic Catalog (2003-2007) Catalogo della Sismicità Italiana CSI v2.0

Earthquake catalogues are the basic tools that furnish parametric data for seismic hazard evaluation, studies on evolution of seismic sequences and earthquake occurrence. The INGV seismic network covers a large part of the italian region and it is complemented by several regional permanent network handled by other institutions. CSI results from the combination of INGV seismic bulletin with bulletins produced by other institutions. To update CSI from previous release to version 2.0 we collected seismic bulletins sent to INGV from, at present, 12 institutions managing permanent seismic networks during 2003-2007. Procedures to convert different file formats to PHS format as input files of Hypoellipse program have been setup that also perform preliminary checks on possible errors. To correctly merge different seismic bulletins it is mandatory to have a strict control on phase associations. To do this, additional procedures to identify earthquakes external to the interest area and wrong associations of different earthquakes based on geographic control network associations and stations' residuals after event location have been produced. About 35,000 eartquakes, a mean value of ~6600 earthquakes per year, with more than 600.000 P-phase arrivals and more then 250,000 S-phase arrivals have been collected and located with Hypoellipse. To enhance final locations quality we applied a multiple location approach and then selected the best among several calculated hypocentres for each event. Location criteria are based on the use of two different weighting schemes for stations' distance combined with several reference regional 1D velocity models. Native Ml Magnitudes from 2003 to 2007 are retrieved and then associated to the corresponding event from INGV bulletin. When native Ml is not available, Ml based on regression law by Castello et al. 2007, is attributed. The update of CSI catalog, also due to the strong improvement of the INGV seismic network between 2005 and present, offers a more complete image of the Italian seismicity and a new important reference for further studies on the evolution of this region and earthquake occurrence

An Overview of Human Reliability Analysis Techniques in Manufacturing Operations

In recent years, there has been a decrease in accidents due to technical failures through technological developments of redundancy and protection, which have made systems more reliable. However, it is not possible to talk about system reliability without addressing the failure rate of all its components; among these components, "man" – because his rate of error changes the rate of failure of components with which he interacts. It is clear that the contribution of the human factor in the dynamics of accidents – both statistically and in terms of severity of consequences – is high [2]. Although valid values are difficult to obtain, estimates agree that errors committed by man are responsible for 60–90% of the accidents; the remainder of accidents are attributable to technical deficiencies [2,3,4]. The incidents are, of course, the most obvious human errors in industrial systems, but minor faults can seriously reduce the operations performances, in terms of productivity and efficiency. In fact, human error has a direct impact on productivity because errors affect the rates of rejection of the product, thereby increasing the cost of production and possibly reduce subsequent sales. Therefore, there is need to assess human reliability to reduce the likely causes of errors [1]. The starting point of this work was to study the framework of today’s methods of human reliability analysis (HRA): those quantitative of the first generation (as THERP and HCR), those qualitative of second (as CREAM and SPAR-H), and new dynamic HRA methods and recent improvements of individual phases of HRA approaches. These methods have, in fact, the purpose of assessing the likelihood of human error – in industrial systems, for a given operation, in a certain interval of time and in a particular context – on the basis of models that describe, in a more or less simplistic way, the complex mechanism that lies behind the single human action that is potentially subject to error [1]. The concern in safety and reliability analyses is whether an operator is likely to make an incorrect action and which type of action is most likely [5]. The goals defined by Swain and Guttmann (1983) in discussing the THERP approach, one of the first HRA methods developed, are still valid: The objective of a human reliability analysis is ‘to evaluate the operator’s contribution to system reliability’ and, more precisely, ‘to predict human error rates and to evaluate the degradation to human–machine systems likely to be caused by human errors in association with equipment functioning, operational procedures and practices, and other system and human characteristics which influence the system behavior’ [7]. The different HRA methods analysed allowed us to identify guidelines for determining the likelihood of human error and the assessment of contextual factors. The first step is to identify a probability of human error for the operation to be performed, while the second consists of the evaluation through appropriate multipliers, the impact of environmental, and the behavioural factors of this probability [1]. The most important objective of the work will be to provide a simulation module for the evaluation of human reliability that must be able to be used in a dual manner [1]: In the preventive phase, as an analysis of the possible situation that may occur and as evaluation of the percentage of pieces discarded by the effect of human error; In post-production, to understand what are the factors that influence human performance so they can reduce errors. The tool will also provide for the possibility of determining the optimal configuration of breaks through use of a methodology that, with assessments of an economic nature, allow identification of conditions that, in turn, is required for the suspension of work for psychophysical recovery of the operator and then for the restoration of acceptable values of reliability [1]

Fluorescence Spectroscopy for the Diagnosis of Endometritis in the Mare

By exploiting the PMN property to produce high quantities of oxygen peroxide to neutralize pathogens, the oxygen peroxide content of uterine cells was measured to diagnose endometritis. After preliminary in vitro studies in which endometrial cells from slaughtered mares were mixed with leukocytes from peripheral blood, endometrial samples were collected by uterine flushing from mares before insemination. Staining endometrial cells with H2DCF‐DA was combined with hydroethidine to normalize the fluorescence intensity with the cellular content of the sample. Stained cell smears were assumed as the gold standard of endometritis, and based on this assay, the samples were considered positive (C+) and negative (C−) for endometritis. The amount and the turbidity of fluid recovered by uterine flushing were significantly (p < 0.01) higher in C+ than in C−. Moreover, the oxygen peroxide content of the endometrial cells was significantly higher in the C+ than in the C− group (6.31 ± 1.92 vs. 3.12 ± 1.26, p = 0.001). Using the value of 4.4 as the cutoff level of this fluorescence cytology assay, it was found that only one C− sample exceeded the cutoff level (false positives = 7.7%) while three C+ samples showed values below the cutoff level (false negative = 11.5%)

I libri dei Patriarchi 2.0. Un percorso multimediale nella cultura scritta del Friuli medievale

Poster sul progetto "I libri dei patriarchi 2.0. Un percorso multimediale nella cultura scritta del Friuli medievale\u201d: obiettivi, scelte metodologiche, elementi di innovativit\ue0 ed originalit\ue0" presentato nell'ambito del Quinto Convegno Annuale AIUCD (Associazione per l'Informatica umanistica e la cultura digitale

No kinematical difference between ultra-congruent and medial-congruent total knee arthroplasty when implanted with mechanical alignment: an in vivo dynamic RSA study

Purpose: To explore in vivo kinematical behavior of the same total knee arthroplasty (TKA) cruciate-retaining (CR) femoral design with either medial-congruent (MC) or ultra-congruent (UC) inlay using model-based dynamic radiostereometric analysis (RSA). The hypothesis was that there would be comparable kinematics between the two groups. Methods: A cohort of 16 randomly selected patients (8 MC Persona Zimmer, 8 UC Persona Zimmer) was evaluated through dynamic radiostereometric analysis (RSA) at a minimum of 9 months after TKA, during the execution of a sit-to-stand. The antero-posterior (AP) translation of the femoral component and the AP translation of the low point of medial and lateral femoral compartments were compared through Student's t test (p < 0.05). Results: Both groups showed a medial pivot behavior, with a significantly greater anterior translation of the Low Point of the lateral compartment with respect to the medial compartment (MC medial range: 2.4 ± 2.4 mm; MC lateral range: 7.7 ± 3.0 mm; p < 0.001 - UC medial range: 3.3 ± 3.3 mm; UC lateral range: 8.0 ± 3.2 mm; p < 0.001). A statistically significant greater degree of flexion was clinically recorded at follow-up visit in the MC group respect to the UC group (126° vs 101°-p = 0.003). Conclusion: The present study did not show difference in the medial pivot behavior between ultra-congruent and medial-congruent total knee arthroplasty when implanted with mechanical alignment; however, the MC group demonstrated a greater degree of flexion. The MC design examined is a valid alternative to the UC design, allowing to achieve a screw-home movement restoration combined with a high flexion

Arc-Jet Testing on HfB2-TaSi2 Models: Effect of the Geometry on the Aerothermal Behaviour

Arc-jet experiments in high enthalpy hypersonic (Mach 3) non equilibrium flow were carried out on a HfB2 composite with addition of 15 vol% TaSi2, at temperatures exceeding 2000 K. The aerothermal behaviour was tested considering models having two different geometries, i.e. hemispheric and cone-shaped. The surface temperature and emissivity of the material were evaluated during the tests. Numerical computations of the nozzle flow were carried out in order to identify the flow conditions around the model and to analyze the details of thermal heating. The chemical- physical modifications were analysed after exposures. The surface emissivity changed from 0.85 to 0.5 due to surface oxidation. The maximum temperatures reached on the tip were strongly dependent on the sample geometry, being around 2300 K for the hemisphere and 2800 K for the cone. Post test SEM analyses confirmed an excellent stability for this HfB2-based materia