1,464 research outputs found

    Philosophy of history of Giambattista Vico

    Get PDF
    The title of my thesis may lead the reader to expect to find in it rather more and different things than there actually are. Because of this I think it advisable to outline some of the restrictions which have been imposed upon it and some of the reasons which explain these. The first and most important restriction lies in the fact that it is mainly confined to the exposition and elucidation of Vico's theories. There is little philosophical discussion of the tenability and value of his ideas and such as I have been able to include i3 largely to be found in the brief concluding section. I have found it necessary to omit altogether any comparisons of Vico with latter-day thinkers of his type, e.g. Hegel, Spengler and Toynbee. A variety of reasons have contributed towards this. Hie first is the obscure, diffuse and often muddled nature of "Hie New Science", which is notoriously difficult to understand. In part this problem arises not so much from the difficulty of the ideas as from the fact that there are so many of them. But this alone would not be a reason for puzzlement. It becomes so when allied to a second factor: the difficulty of understanding the meaning of some of Vico's principal pronouncements about the nature of the enterprise carried out in "The New Science" and about the relationships between at least some of its main theories. It is admitted on all hands that Vico's language is obscure. I should not want to dispute this and, indeed, have had to go to some lengths to try to clear up a few of these obscurities. It is also alleged sometimes that some of the difficulties of understanding 'The Now Science" arise from philosophical confusions. This is a much more disputable claim, it will become clear in the following work that I hold that Vico was by no means so confused in his grasp of his own doctrines as the general obscurity of "The New Science" might suggest. Certainly I do not think that he was guilty of one or two basic philosophical confusions which, if located, would provide the clue to the unravelling of most of the difficulties of his work. Nor do I think that those mistakes which he does make are so fundamental that he is left with nothing of importance to say once they have been rectified

    Peri-implant diseases and metabolic syndrome components: a systematic review

    Get PDF
    OBJECTIVE: Metabolic syndrome (MetS) is defined as a spectrum of conditions associated with an increased risk of developing CVD and type 2 diabetes. MetS include: hyperglycemia, hypertension, visceral obesity, dyslipidemia with elevated values of triglycerides (TG) and low levels of HDL. The aim of this review is to provide current knowledge of the relationship between MetS, its components and peri-implant diseases. MATERIALS AND METHODS: An electronic literature search was conducted in the English language in several databases. The Newcastle-Ottawa Scale was used for quality assessment of cohort and cross-sectional studies; while systematic reviews were evaluated through AMSTAR; results were reported according to the PRISMA Statement. RESULTS: A total of 272 records were identified through database searching, six studies were included for qualitative analysis. No study directly related to MetS was found, there was inconsistent and controversial evidence regarding association with cardiovascular disease. A higher risk of peri-implantitis was detected in people with hyperglycemia. CONCLUSIONS: Future research should be orientated in assessing the risk of peri-implant diseases, evaluating patient's therapeutic response, analyzing directionality of the relationship between MetS, its components and biologic implant complications. Few studies have investigated the possible relationship between systemic conditions and peri-implant diseases. The aim of this review is to present, in a systematic manner, current evidence and knowledge regarding possible association between cardiovascular disease and implant biologic complications. Out of the one-hundred-eighty-nine studies screened, just five studies were selected for qualitative analysis: three cohort studies (one prospective and two retrospectives) and two cross-sectional studies. According to their results, there is inconsistent and controversial evidence regarding association of cardiovascular disease and implant biologic complications. Future research should be orientated in conducting longitudinal studies, evaluating patients affected by cardiovascular disease rehabilitated with dental implants

    Histological and immunohistochemical evaluation of mandibular bone tissue regeneration

    Get PDF
    The purpose of the study was to perform an immunohistochemical and histological evaluation of samples taken from different bone regeneration procedures in atrophic human mandible. 30 patients (15 men and 15 women, age range of 35-60 years), non-smokers, with good general and oral health were recruited in this study and divided into three groups. The first group included patients who were treated with blood Concentration Growth Factors (bCGF), the second group included patients who were treated with a mixture of bCGF and autologous bone, while the third group of patients was treated with bCGF and tricalcium phosphate/hydroxyapatite (TCP-HA). Six months after the regenerative procedures, all patients undergone implant surgery, and a bone biopsy was carried out in the site of implant insertion. Each sample was histologically and immunohistochemically examined. Histological evaluation showed a complete bone formation for group II, partial ossification for group I, and moderate ossification for group III. Immunohistochemical analysis demonstrated a statistically significant difference between the three groups, and the best clinical result was obtained with a mixture of bCGF and autologous bone

    Sensor for Distance Measurement Using Pixel Grey-Level Information

    Get PDF
    An alternative method for distance measurement is presented, based on a radiometric approach to the image formation process. The proposed methodology uses images from an infrared emitting diode (IRED) to estimate the distance between the camera and the IRED. Camera output grey-level intensities are a function of the accumulated image irradiance, which is also related by inverse distance square law to the distance between the camera and the IRED. Analyzing camera-IRED distance, magnitudes that affected image grey-level intensities, and therefore accumulated image irradiance, were integrated into a differential model which was calibrated and used for distance estimation over a 200 to 600 cm range. In a preliminary model, the camera and the emitter were aligned

    Prevalence and treatment of retrograde peri-implantitis: a retrospective cohort study covering a 20-year period

    Get PDF
    Objectives: The aims of this retrospective study were to report data on the prevalence of retrograde peri-implantitis (RPI) in a single-center in a 20-year observation period and to evaluate implant survival after surgical treatment. Materials and methods: A retrospective cohort study was conducted screening all patients who underwent implant treatment in a private practice. Patients were enrolled if they had one or more implants showing a radiolucency around the implant apex, without implant mobility. Furthermore, clinical symptoms of RPI and days from symptoms’ appearance after implant placement were also collected, as well as periodontal and endodontic status of nearby teeth. All patients were treated with the same surgical approach: antibiotic therapy, mechanical curettage, chemical decontamination and xenograft application. Results: Out of the 1749 implants placed, only 6 implants were classified as affected by RPI, with a prevalence of 0.34%. Clinical symptoms of RPI (pain, swelling, dull percussion or fistula presence) varied among patients and were reported after a mean period of 51.83 ± 52.43 days. Conclusions: RPI was successfully treated with surgical curettage and bone substitute application and all implants are still in place after a mean follow-up of 8.83 ± 5.34 years. Clinical relevance: Bacteria from teeth with failed endodontic treatment or residual lesions might be reactivated by drilling for implant osteotomy, with subsequent colonization of the implant apex and possible failure before prosthetic loading. Therefore, it might be recommended to take a periapical x-ray at implant placement and after 6–8 weeks in order to intercept RPI before prostheses delivery

    Olive fruits infested with olive fly larvae respond with an ethylene burst and the emission of specific volatiles

    Get PDF
    Olive fly (Bactrocera oleae R.) is the most harmful insect pest of olive (Olea europaea L.) which strongly affects fruits and oil production. Despite the expanding economic importance of olive cultivation, up to now, only limited information on plant responses to B. oleae is available. Here, we demonstrate that olive fruits respond to B. oleae attack by producing changes in an array of different defensive compounds including phytohormones, volatile organic compounds (VOCs), and defense proteins. Bactrocera oleae-infested fruits induced a strong ethylene burst and transcript levels of several putative ethylene-responsive transcription factors became significantly upregulated. Moreover, infested fruits induced significant changes in the levels of 12-oxo-phytodienoic acid and C12 derivatives of the hydroperoxide lyase. The emission of VOCs was also changed quantitatively and qualitatively in insect-damaged fruits, indicating that B. oleae larval feeding can specifically affect the volatile blend of fruits. Finally, we show that larval infestation maintained high levels of trypsin protease inhibitors in ripe fruits, probably by affecting post-transcriptional mechanisms. Our results provide novel and important information to understand the response of the olive fruit to B. oleae attack; information that can shed light onto potential new strategies to combat this pes

    Amyloid-like fibrils in elastin-related polypeptides: Structural characterization and elastic properties

    Get PDF
    We report on the structural characterization of amyloid-like fibrils, self-assembled from synthetic polypentapeptides poly(ValGlyGlyLeuGly), whose monomeric sequence is a recurring, simple building block of elastin. This polymer adopts a beta-sheet structure as revealed by circular dichroism and Fourier transform infrared spectroscopy. Furthermore, Thioflavin-T and Congo red birefringence assays confirm the presence of amyloid-like structures. To analyze the supramolecular assembly and elastic properties of the fibrils, we employed atomic force microsocopy and spectroscopy, measuring also the elasticity of mature elastin for a comparative analysis. In the case of fibrils we estimated a Young's modulus ranging from 3.5 to 7 MPa, whereas for elastin it is around 1 MPa. The possibility to section individual fibrils with nanometric control by the AFM tip, realizing biomolecular gaps in the 100 nm range, is also demonstrated. These results are expected to open interesting perspectives for the fabrication of protein-inspired nanostructures with specific physical and chemical properties for applications in biotechnology and tissue engineering

    Enhanced epidemiological surveillance of influenza A(H1N1)v in Italy.

    Get PDF
    As of 7 July 2009, a total of 158 laboratory-confirmed cases of influenza A(H1N1)v were reported in Italy, from half of the 21 Italian regions. To date all cases have had symptoms consistent with seasonal influenza and no severe or fatal cases have been reported. An active surveillance of cases has been set up in Italy in order to undertake appropriate measures to slow down the spread of the new virus. This report describes the routine and enhanced surveillance currently ongoing in Italy
    • …
    corecore