102 research outputs found

    The concept of knowledge as a methodological instrument for analysing organizations and information systems

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    This work focuses of the concept of knowledge as instrument for inquiring into organization and information systems. For this proposal a threefold classification of this concept has been introduced: the individual sphere (the knowledge that is within each subject in the form of skills, values and beliefs), the organizational sphere (procedures, routines, roles and technology) and the interorganizational sphere (opportunities, obligations, utilities and facilities that characterize the environment in which companies do business) of knowledge. Through this classification, a number of theoretical approaches are going to be taken into examination to see, respectively, which sphere of knowledge they cover. Therefore it will emerge that one approach can delineate in detail the interorganizational sphere of knowledge having some limits to render the individual sphere and vice-versa. The examination of organizations and information systems using this concept exhibits these methodological features: a methodology that permits the inspection in an organic way of the different aspects that characterize organizations and information systems; a methodology that evaluates the different theoretical approaches and a methodology that manages the data and information at our disposal. The latter can be directly assigned to one of the three spheres and then analysed according to an appropriate theoretical approach

    Human dental pulp stem cells produce mineralized matrix in 2D and 3D cultures

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    The aim of this study was to characterize the in vitro osteogenic differentiation of dental pulp stem cells (DPSCs) in 2D cultures and 3D biomaterials. DPSCs, separated from dental pulp by enzymatic digestion, and isolated by magnetic cell sorting were differentiated toward osteogenic lineage on 2D surface by using an osteogenic medium. During differentiation process, DPSCs express specific bone proteins like Runx-2, Osx, OPN and OCN with a sequential expression, analogous to those occurring during osteoblast differentiation, and produce extracellular calcium deposits. In order to differentiate cells in a 3D space that mimes the physiological environment, DPSCs were cultured in two distinct bioscaffolds, Matrigel™ and Collagen sponge. With the addition of a third dimension, osteogenic differentiation and mineralized extracellular matrix production significantly improved. In particular, in Matrigel™ DPSCs differentiated with osteoblast/osteocyte characteristics and connected by gap junction, and therefore formed calcified nodules with a 3D intercellular network. Furthermore, DPSCs differentiated in collagen sponge actively secrete human type I collagen micro-fibrils and form calcified matrix containing trabecular-like structures. These neo-formed DPSCs-scaffold devices may be used in regenerative surgical applications in order to resolve pathologies and traumas characterized by critical size bone defects

    The Emergency Surgery Frailty Index (EmSFI) in Elderly Patients with Acute Appendicitis: An External Validation of Prognostic Score

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    Background: Identification of reliable risk-stratification tools is critical for surgical decision making, particularly in frail and elderly. The aim of the study is to validate the Emergency Surgery Frailty Index (EmSFI), in over 65 years old patients operated on for acute appendicitis. Methods: An observational study was conducted enrolling elderly patients with diagnosis of acute appendicitis who underwent emergency appendicectomy or right colectomy, between 2016 and 2021. All patients were treated according to the last SIFIPAC/WSES/SICG/SIMEU guidelines. Results: Overall, 61 patients were analyzed. Complication rate was higher for patients in the second EmSFI risk Class. Moreover, ROC analyses identified 3 as the best cutoff value in predicting risk of adverse postoperative events. Complication rate was higher in oldest elderly patients—over 80 years—(42.9 vs 22.5%; p 0.05) and was mainly related to medical complications (42.9 vs 12.5%, p 0.007). However, intestinal obstruction, peri-appendicular abscess on preoperative CT, peritonitis and a longer duration of surgery are related with increased risk of complications in the group of patients under 80 years. Conclusion: The EmSFI score results a valid prognostic marker for frailty status, and it may support the surgeon in emergency setting for acute appendicitis. Patients aged 80 years or older have a higher risk of complications, independent from those factors which relate to increased morbidity in younger elderly patients. Age alone is not a reliable indicator of the real surgical risk, but it must encourage the adoption of multidisciplinary collaborative models of care for this group of patients. © 2023, The Author(s)

    Ruolo della stimolazione bimodale nello sviluppo delle abilitĂ  percettivo-uditive nei bambini con impianto cocleare monolaterale

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    Il presente studio prospettico randomizzato ha lo scopo di valutare le differenze che emergono tra una stimolazione bimodale e una elettrica monolaterale nei bambini sordi, in particolare in termini di sviluppo delle abilità percettivo-uditive. Sono stati arruolati 39 bambini di età compresa tra i 12 e 36 mesi di vita, affetti da ipoacusia neurosensoriale bilaterale severo-profonda con residui uditivi in almeno un orecchio. Tutti i pazienti sono stati sottoposti a impianto cocleare monolaterale: 21 di questi indossavano solo l’impianto (stimolazione elettrica monolaterale, Gruppo 1) mentre i restanti 18 utilizzavano l’impianto da una parte e la protesi acustica controlaterale dall’altra (stimolazione bimodale, Gruppo 2). Ciascuno di questi pazienti è stato sottoposto a una batteria di test progettata per valutare le abilità percettivo-uditive preverbali e verbali immediatamente prima e a distanza di 6 e 12 mesi dall’intervento di impianto cocleare. Non si è apprezzata una differenza statisticamente significativa tra i gruppi al tempo 0, mentre a 6 e 12 mesi dall’impianto i pazienti con stimolazione bimodale ottenevano in ogni test somministrato prestazioni migliori del gruppo con sola stimolazione elettrica monolaterale. Di conseguenza, nonostante la sordità/udito monolaterale non infici l’acuità uditiva in situazioni d’ascolto semplici, l’uso contemporaneo dell’impianto e della protesi (udito binaurale attraverso una stimolazione bimodale) garantisce un vantaggio nella acquisizione delle abilità percettivo-uditive, consistente nel raggiungimento delle tappe dello sviluppo percettivo più velocemente e in maggiore quantità rispetto ai bambini con solo un impianto cocleare. Perciò, mantenere attiva la rete nervosa uditiva controlaterale, anche se non dominante nel determinare l’acuità uditiva, garantisce dei benefici rispetto al non uso del dispositivo. Queste informazioni possono rappresentare un’evidenza iniziale per stabilire linee guida condivise per la migliore gestione riabilitativa dei pazienti sottoposti a intervento di impianto cocleare, e possibilmente fornire un’evidenza scientifica solida al fine di una indicazione certa all’impianto cocleare bilaterale

    An ultra-wideband sensing board for IoT

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    In this paper, we present an ultra-wideband impedance sensing board for the radio-frequency front-ends used in wireless units for the Internet of Things and the fifth-generation wireless communication systems. We adopt as an impedance sensing board a six-port junction which was designed, fabricated, and tested experimentally in the frequency range from 5 GHz to 6 GHz. Moreover, the sensing board functionality was fully validated with load-pull measurements carried out in the same frequency range

    Label-Free Optical Sensing and Medical Grade Resins: An Advanced Approach to Investigate Cell–Material Interaction and Biocompatibility

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    : The Corning Epic® label-free (ELF) system is an innovative technology widely used in drug discovery, immunotherapy, G-protein-associated studies, and biocompatibility tests. Here, we challenge the use of ELF to further investigate the biocompatibility of resins used in manufacturing of blood filters, a category of medical devices representing life-saving therapies for the increasing number of patients with kidney failure. The biocompatibility assays were carried out by developing a cell model aimed at mimicking the clinical use of the blood filters and complementing the existing cytotoxicity assay requested by ISO10993-5. Experiments were performed by putting fibroblasts in both direct contact with two types of selected resins, and indirect contact by means of homemade customized well inserts that were precisely designed and developed for this technology. For both types of contact, fibroblasts were cultured in medium and human plasma. ELF tests confirmed the biocompatibility of both resins, highlighting a statistically significant different biological behavior of a polyaromatic resin compared to control and ion-exchanged resin, when materials were in indirect contact and soaking with plasma. Overall, the ELF test is able to mimic clinical scenarios and represents a promising approach to investigate biocompatibility, showing peculiar biological behaviors and suggesting the activation of specific intracellular pathways

    Oxidative stress and erythrocyte membrane alterations in children with autism: correlation with clinical features

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    It has been suggested that oxidative stress may play a role in the pathogenesis of Autism Spectrum Disorders (ASD), but the literature reports somewhat contradictory results. To further investigate the issue, we evaluated a high number of peripheral oxidative stress parameters, and some related issues such as erythrocyte membrane functional features and lipid composition. Twenty-one autistic children (Au) aged 5 to 12 years, were gender and age-matched with 20 typically developing children (TD). Erythrocyte thiobarbituric acid reactive substances, urinary isoprostane and hexanoyl-lysine adduct levels were elevated in Au, thus confirming the occurrence of an imbalance of the redox status of Au, whilst other oxidative stress markers or associated parameters (urinary 8-oxo-dG, plasma radical absorbance capacity and carbonyl groups, erythrocyte superoxide dismutase and catalase activities) were unchanged. A very significant reduction of Na+/K+-ATPase activity (-66%, p<0.0001), a reduction of erythrocyte membrane fluidity and alteration in erythrocyte fatty acid membrane profile (increase in monounsaturated fatty acids, decrease in EPA and DHA-\u3c93 with a consequent increase in \u3c96/\u3c93 ratio) were found in Au compared to TD, without change in membrane sialic acid content. Some Au clinical features appear to be correlated with these findings; in particular, hyperactivity score appears to be related with some parameters of the lipidomic profile and membrane fluidity. Oxidative stress and erythrocyte membrane alterations may play a role in the pathogenesis of ASD and prompt the development of palliative therapeutic protocols. Moreover, the marked decrease in NKA could be potentially utilized as a peripheral biomarker of ASD
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