923 research outputs found

    Cortical spatio-temporal dimensionality reduction for visual grouping

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    The visual systems of many mammals, including humans, is able to integrate the geometric information of visual stimuli and to perform cognitive tasks already at the first stages of the cortical processing. This is thought to be the result of a combination of mechanisms, which include feature extraction at single cell level and geometric processing by means of cells connectivity. We present a geometric model of such connectivities in the space of detected features associated to spatio-temporal visual stimuli, and show how they can be used to obtain low-level object segmentation. The main idea is that of defining a spectral clustering procedure with anisotropic affinities over datasets consisting of embeddings of the visual stimuli into higher dimensional spaces. Neural plausibility of the proposed arguments will be discussed

    Vinca il migliore. L’agonismo nel mondo naturale dal nucleo atomico alla scala cosmica

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    Il progetto 2016 del ciclo La Curiosità fa lo Scienziato ha proposto una riflessione sui temi della competizione e collaborazione nel mondo naturale, coinvolgendo gli ambiti disciplinari di fisica, chimica e scienze naturali. In tutto il mondo naturale osservabile equilibri e dinamiche sono riconducibili ad entità in competizione, secondo regole che si vanno scoprendo man mano che aumenta la capacità di interrogare la natura. In fisica entrano nell’arena poche forze fondamentali, dalla micro scala atomica fino alla macro scala cosmologica. In chimica diversi composti competono nel determinare l’evoluzione e gli effetti delle reazioni. Nel mondo biologico il rapporto che si stabilisce in un determinato ambiente tra le varie specie animali e vegetali, legate tra loro da relazioni antagonistiche, ma anche mutualistiche, è condizione indispensabile per la sopravvivenza. Gli incontri previsti all’interno del Progetto, dedicati a platee di età diverse, hanno sempre incluso conversazioni a tema arricchite da esperimenti includendo in talune circostanze anche esecuzioni di brani musicali. Le attività hanno complessivamente raggiunto un pubblico di circa 1200 persone. Nel seguito vengono elencate e brevemente descritte le varie attività svolte. Il materiale documentale prodotto durante il Progetto è messo a disposizione a libero accesso sul sito del Dipartimento di Scienze Fisiche, Informatiche e Matematiche dell’Università di Modena e Reggio Emilia al link: http://www.outreach.fim.unimore.it/site/home/divulgazione/la-curiosita-fa-lo-scienziat

    La Xiloteca Storica dell’Orto Botanico di Modena

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    Nell’ambito dei progetti di valorizzazione museale delle collezioni storiche, in corso presso l’Orto Botanico dell’Università di Modena e Reggio Emilia, un recente intervento ha riguardato la Xiloteca Storica e, in particolare, 345 campioni di legno acquisiti nel periodo 1890-1969, provenienti sia da esemplari abbattuti nell’Orto Botanico modenese che da raccolte effettuate in natura oppure da donazioni da parte di istituzioni o privati

    Dibutyltin(IV) and Tributyltin(IV) Derivatives of meso-Tetra(4-sulfonatophenyl)porphine Inhibit the Growth and the Migration of Human Melanoma Cells

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    Melanoma is the most aggressive and deadly form of skin cancer, which is largely due to its propensity to metastasize. Therefore, with the aim to inhibit the growth and the metastatic dissemination of melanoma cells and to provide a novel treatment option, we studied the eects of the melanoma treatment with two organotin(IV) complexes of the meso-tetra(4-sulfonato-phenyl)porphine, namely (Bu2Sn)2TPPS and (Bu3Sn)4TPPS. In particular, we showed that nanomolar concentrations of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS are sucient to inhibit melanoma cell growth, to increase the expression of the full-length poly (ADP-ribose) polymerase (PARP-1), to induce the cell cycle arrest respectively at G2/M and G0/G1 through the inhibition of the Cyclin D1 expression and to inhibit cell colony formation. Nanomolar concentrations of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS are also sucient to inhibit the melanoma cell migration and the expression of some adhesion receptors. Moreover, we report that (Bu2Sn)2TPPS and (Bu3Sn)4TPPS act downstream of BRAF, mainly bypassing its functions, but targeting the STAT3 signalling protein. Finally, these results suggest that (Bu2Sn)2TPPS and (Bu3Sn)4TPPS may be eective therapeutic strategies for their role in the inhibition of melanoma growth and migration

    Dibutyltin(IV) and Tributyltin(IV) Derivatives of meso-Tetra(4-sulfonatophenyl)porphine Inhibit the Growth and the Migration of Human Melanoma Cells

    Get PDF
    Melanoma is the most aggressive and deadly form of skin cancer, which is largely due to its propensity to metastasize. Therefore, with the aim to inhibit the growth and the metastatic dissemination of melanoma cells and to provide a novel treatment option, we studied the eects of the melanoma treatment with two organotin(IV) complexes of the meso-tetra(4-sulfonato-phenyl)porphine, namely (Bu2Sn)2TPPS and (Bu3Sn)4TPPS. In particular, we showed that nanomolar concentrations of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS are sucient to inhibit melanoma cell growth, to increase the expression of the full-length poly (ADP-ribose) polymerase (PARP-1), to induce the cell cycle arrest respectively at G2/M and G0/G1 through the inhibition of the Cyclin D1 expression and to inhibit cell colony formation. Nanomolar concentrations of (Bu2Sn)2TPPS and (Bu3Sn)4TPPS are also sucient to inhibit the melanoma cell migration and the expression of some adhesion receptors. Moreover, we report that (Bu2Sn)2TPPS and (Bu3Sn)4TPPS act downstream of BRAF, mainly bypassing its functions, but targeting the STAT3 signalling protein. Finally, these results suggest that (Bu2Sn)2TPPS and (Bu3Sn)4TPPS may be eective therapeutic strategies for their role in the inhibition of melanoma growth and migration

    Caduta accidentale di una paziente sottoposta a riduzione chirurgica di frattura di femore: analisi delle cause profonde

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    Introduction. Inpatient falls in hospital is a relevant problem. The first essential step is to know the risks to prevent them, through reactive or proactive analysis. In this study we used the Root Causes Analysis (RCA) to analyze an accidental fall of a 79-year-old patient after a surgical intervention for a femoral fracture. The aim of the analysis is to evaluate the effect of this method on sanitary professionals. Material and methods. The study was conducted at the Operative Unity of Orthopaedics and Traumatology, “Beato Matteo Institute”, Vigevano. RCA was realised in the following steps: creation of the team, individuation of the causes, collection and evaluation of the information, identification of the solutions and the proposals of improvement. Results. The RCA showed the following causes: incomplete assessment of the patient, lacking professional skills, lacking of procedures and safety systems, risk factors connected both to the patient and the environment. The improvement proposals were: education and information of professionals, education of patient and caregivers, nursing interventions, environmental strategies and signalling systems. Discussion. RCA is an useful tool for risk management and it allowed to highlight causes and corrective actions of the accidental fall. Furthermore, this case allowed to underline advantages and disadvantages of this method. Advantages were the involvement of different professionals and sharing of objectives of systems improvement; the importance of the introduction of new instruments for risks identification and specific education to use them. Among the disadvantages we can list: difficulties in finding all the informations to correctly analyse the case, perception of too much bureaucracy in the procedure, and fear of a “punitive” use of the information collected

    Management of QT prolongation induced by anti-cancer drugs: Target therapy and old agents. Different algorithms for different drugs

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    The side effects of anticancer drugs still play a critical role in survival and quality of life. Although the recent progresses of cancer therapies have significantly improved the prognosis of oncologic patients, side effects of antineoplastic treatments are still responsible for the increased mortality of cancer survivors. Cardiovascular toxicity is the most dangerous adverse effect induced by anticancer therapies. A survey conducted by the National Health and Nutrition Examination, showed that 1807 cancer survivors followed up for seven years: 51% died of cancer and 33% of heart disease (Vejpongsa and Yeh, 2014). Moreover, the risk of cardiotoxicity persists even with the targeted therapy, the newer type of cancer treatment, due to the presence of on-target and off-target effects related to this new class of drugs. The potential cardiovascular toxicity of anticancer agents includes: QT prolongation, arrhythmias, myocardial ischemia, stroke, hypertension (HTN), thromboembolism, left ventricular dysfunction and heart failure (HF). Compared to other cardiovascular disorders, the interest in QT prolongation and its complications is fairly recent. However, oncologists have to deal with it and to evaluate the risk-benefit ratio before starting the treatment or during the same. Electrolyte abnormalities, low levels of serum potassium and several drugs may favour the acquired QT prolongation. Treatment of marked QT prolongation includes cardiac monitoring, caution in the use or suspension of cancer drugs and correction of electrolyte abnormalities (hypokalaemia, hypomagnesaemia, hypocalcaemia). Syndrome of QT prolongation can be associated with potentially fatal cardiac arrhythmias and its treatment consists of intravenous administration of magnesium sulphate and the use of electrical cardioversion
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