Socrates and Leisure

In the so-called Socratic dialogues, Socrates introduces the need for σχολή or leisure as the precondition that is necessary for the philosopher to pursue his task. He also makes ideal use of it, contrary to what seems to have been the popular image of the idle philosopher. Thus, a desideratum for academic life was built, on the grounds that philosophers have to reciprocate the gift of leisure by benefiting the whole of community; besides, the idea of intellectual labour was also introduced to balance any negative feelings created in the demos against the luxurious leisure of philosophers and their schools. Philosophical leisure and its conditions could well be an issue in modern academic ethics

Radiation protection considerations along a radioactive ion beam transport line

The goal of the SPES project is to produce accelerated radioactive ion beams for Physics studies at "Laboratori Nazionali di Legnaro" (INFN, Italy). This accelerator complex is scheduled to be built by 2016 for an effective operation in 2017. Radioactive species are produced in a uranium carbide target, by the interaction of 200 [Formula: see text]A of protons at 40 MeV. All of the ionized species in the 1+ state come out of the target (ISOL method), and pass through a Wien filter for a first selection and an HMRS (high mass resolution spectrometer). Then they are transported by an electrostatic beam line toward a charge state breeder (where the 1[Formula: see text] to n[Formula: see text] multi-ionization takes place) before selection and reacceleration at the already existing superconducting linac. The work concerning dose evaluations, activation calculation, and radiation protection constraints related to the transport of the radioactive ion beam (RIB) from the target to the mass separator will be described in this paper. The FLUKA code has been used as tool for those calculations needing Monte Carlo simulations, in particular for the evaluation of the dose rate due to the presence of the radioactive beam in the selection/interaction points. The time evolution of a radionuclide inventory can be computed online with FLUKA for arbitrary irradiation profiles and decay times. The activity evolution is analytically evaluated through the implementation of the Bateman equations. Furthermore, the generation and transport of decay radiation (limited to gamma, beta- and beta[Formula: see text] emissions) is possible, referring to a dedicated database of decay emissions using mostly information obtained from NNDC, sometimes supplemented with other data and checked for consistency. When the use of Monte Carlo simulations was not feasible, the Bateman equations, or possible simplifications, have been used directly

An Evaluation of the Performance of Hotel Web Sites Using the Managers\u27 View About Online Information Services

This paper describes a quantitative method of measurement and evaluation of the information provided by hotel websites. It aims to measure the richness of specific and comprehensive information dimensions, which as a whole constitute the information services offered through the web. Data from an extended web search along with responses of hotel managers regarding the importance of the offered information services are used. A conceptual model that describes the hotel web sites information features is used in order to summarize the data and to present the overall information volume offered. The applied model combines seven data dimensions: facilities information, customer contact information, reservation and prices information, surrounding area information, management of the web site, company information and communication. Hotel managers’ perceptions are used to weight the relative importance of both the information services and the seven dimensions. We apply the model to Greek hotel web sites. Greek hotels make small use of their websites potential. They are rated low level with respect to crucial dimensions such as reservation and prices information, medium regarding facilities and customer contact information. The overall volume of offered information only reaches the one third of its top rating score

Socket preservation, sinus lift and lateral augmentation by using natural bovine bone substitute with hyaluronate

It is very important to have sufficient bone volume that allows proper implants osseointegration. The aim of this case report was to observe a socket preservation and sinus lift with lateral augmentation by using xenograft granules with hyaluronate and pericardium collagen membrane. The sufficient granules osteointegration into newly formed bone after six months enabled proper implants placement due obvious bone volume increase. The implants were completely integrated into the regenerated bone after four months and then were loaded. The use of xenograft granules with hyaluronate led to successful treatment in combination with pericardium collagen membrane in socket preservation and sinus lift with lateral augmentation

Socket preservation with high-density polytetrafluoroethylene barrier membrane during open healing

Bone volume loss appears after tooth extraction and socket preservation is the most applied procedure to prevent an alveolar resorption. The aim of this study was to retrospectively analyse three socket preservation cases with high-density polytetrafluoroethylene barrier membrane (permamem®) for open healing with and without the use of additional dental regeneration biomaterials. Here no bacterial plaque was present and the soft tissue completely re-epithelialized, which allowed new bone formation and implant treatment. The current findings indicate that the use of this membrane, leads to successful socket treatment during open healing

Use of twitter and Facebook by top European museums

With social media becoming so pervasive, museums strive to adopt them for their own use. Effective use of social media especially Facebook and Twitter seems to be promising. Social media offer museums the possibility to engage audiences, potential and active visitors with their collections and ideas. Facebook and Twitter are the market leaders of social media. This paper records the top European museums and their Facebook and Twitter accounts. It records the use of the two media, and by applying statistical analysis it investigates whether Twitter use is in accordance to Facebook use. Findings reveal that this is not the case. By using Principal Component Analysis and Cluster Analysis the paper finds that there is, however, a district group of top museums which manage to excel in both media mainly by adopting carefully planned strategies and paying attention to the potential and benefits that social media offer

Biological dosimetry of ionizing radiation: Evaluation of the dose with cytogenetic methodologies by the construction of calibration curves

In case of a radiation accident, it is well known that in the absence of physical dosimetry biological dosimetry based on cytogenetic methods is a unique tool to estimate individual absorbed dose. Moreover, even when physical dosimetry indicates an overexposure, scoring chromosome aberrations (dicentrics and rings) in human peripheral blood lymphocytes (PBLs) at metaphase is presently the most widely used method to confirm dose assessment. The analysis of dicentrics and rings in PBLs after Giemsa staining of metaphase cells is considered the most valid assay for radiation injury. This work shows that applying the fluorescence in situ hybridization (FISH) technique, using telomeric/centromeric peptide nucleic acid (PNA) probes in metaphase chromosomes for radiation dosimetry, could become a fast scoring, reliable and precise method for biological dosimetry after accidental radiation exposures. In both in vitro methods described above, lymphocyte stimulation is needed, and this limits the application in radiation emergency medicine where speed is considered to be a high priority. Using premature chromosome condensation (PCC), irradiated human PBLs (non-stimulated) were fused with mitotic CHO cells, and the yield of excess PCC fragments in Giemsa stained cells was scored. To score dicentrics and rings under PCC conditions, the necessary centromere and telomere detection of the chromosomes was obtained using FISH and specific PNA probes. Of course, a prerequisite for dose assessment in all cases is a dose-effect calibration curve. This work illustrates the various methods used; dose response calibration curves, with 95% confidence limits used to estimate dose uncertainties, have been constructed for conventional metaphase analysis and FISH. We also compare the dose-response curve constructed after scoring of dicentrics and rings using PCC combined with FISH and PNA probes. Also reported are dose response curves showing scored dicentrics and rings per cell, combining PCC of lymphocytes and CHO cells with FISH using PNA probes after 10 h and 24 h after irradiation, and, finally, calibration data of excess PCC fragments (Giemsa) to be used if human blood is available immediately after irradiation or within 24 h

Dosimetria biologica delle radiazioni ionizzanti: valutazione della dose con metodologie citogenetiche tramite la costruzione di curve di calibrazione

The assessment of the risk for biological damage of an individual after overexposure to ionizing radiation due to an accident or a terroristic attack passes through the evaluation of the absorbed dose received from the person/s involved. This evaluation, corresponding also to how dangerous the overexposure is, using methodologies typical of the biological dosimetry, is done with the help of reference calibration curves and it presumes that all individuals exposed have the same individual radiosensitivity, which is true when the biological system into account are human lymphocytes of the peripheral blood (PBL). It supposes that a certain dose of radiation produces the same quantity of variation (chromosomal aberrations) in that biological system in all the exposed. The goal of this Ph.D. thesis is the application of various cytogenetic methodologies to detect in a reliable and possibly fast way chromosomal aberrations non stable (dicentrics and centromeric rings) in the lymphocytes of the human peripheral blood after gamma irradiation and the construction of calibration curves dose effect able to give rapidly a response of the absorbed dose in case of radiation accident. The time needed to give a reliable response on the absorbed dose is crucial and this is especially true in radiation emergency medicine. The objective was to standardize, develop and apply sophisticate, sensitive and reliable methodologies for the estimation of the absorbed doses after accidental gamma radiation overexposures for radiation protection purposes. Specifically, in the present study the following were performed: I. Application of the classic “golden standard” methodology of biological dosimetry which provides stimulation of the lymphocytes and Giemsa staining of the chromosomes at mitosis II. Development, consolidation and application of original methodologies in biological dosimetry using fluorescence in situ hybridization (FISH) and peptide nucleic acid (PNA) probes for painting specifically chromosome telomers and centromeres III. Application and consolidation of the method of premature chromosome condensation (PCC) where no stimulation at lymphocytes is needed IV. Development of a fast, sensitive and reliable methodology, absolutely original in the field of biological dosimetry for dose evaluation combining the PCC method with the FISH using PNA probes for centromers and telomers V. Construction for all the above methodologies, using in vitro experiments, of calibration curves dose-effect where unstable chromosomal aberrations where plotted against gamma dose given. The dose interval investigated was between 0.3 Gy and 8 Gy; more than 12.500 slides with metaphases and interphases were scored using Microscopic analysis of chromosome aberrations. Dose effect curves are linear quadratic and for their construction a minimum of 500 cells or 100 dicentrics per dose were analysed. The Poisson distribution of the chromosomal aberrations was tested for every dose and the coefficients alpha and beta of the linear quadratic equation, their errors and p value were calculated. Finally, all calibration curves obtained with the different methodologies were compared and the advantages of each methodology reported