2,170 research outputs found

    Approval plan. Origins, contexts and prospects of an Italian case study: Casalini Libri

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    Questo contributo tratta di un metodo di acquisizione libraria, l'approval plan, e di una delle poche aziende italiane attive in ambito culturale che da anni lo propone e lo pratica riscuotendo un grande successo nel mondo, e solo marginalmente in Italia.Per la stesura di questo studio, la scrivente si è basata, oltre che sulla letteratura esistente, sulla frequentazione della Casalini Libri, dove ha potuto seguire le diverse fasi di lavorazione dell'approval plan, e farsi dare spiegazioni, avere chiarimenti e intrattenere colloqui con i titolari dell'azienda e col personale direttamente coinvolto nelle varie fasi del lavoro. Per avere un quadro più completo della situazione, sono stati interpellati anche responsabili di sistemi bibliotecari, di biblioteche o del settore acquisizione di diverse biblioteche italiane.In conclusione si può affermare che l'approval plan, per le sue caratteristiche, è uno strumento valido ancora oggi. Elementi determinanti per il ricorso ad esso da parte delle biblioteche risultano essere non tanto questioni di tipo economico, che pure non sono trascurabili, ma soprattutto fattori socio-culturali fra cui spiccano l'apertura internazionale e l'ampiezza di orizzonti delle istituzioni a cui le biblioteche appartengono, insieme alla capacità di programmazione da parte degli organi preposti.The article deals with the approval plan method of book acquisition. It discusses the implementation of the approval plan method in one of the few Italian companies active in the cultural sector that offers and provides libraries with this service for many years, enjoying huge success across the world.In preparing this essay, not only the author made valuable use of the existing literature on the topic, but also of the opportunity to spend a period of time within Casalini Libri, the company described above,where she was able to follow the different phases of the approval plan workflow, benefitting from first-hand explanations and clarification on procedures, direct contact and conversations both with approval selectors and the company directors.In order to provide a full overview of the topic, some interviews were held with various directors and heads of acquisitions and library systems of a number of Italian libraries.From this article it can be concluded that approval plans are a highly valuable acquisition method still today.Although economic issues must not be ignored when determining the reasons for which libraries decide to opt for this method, the explanation lies in social and cultural aspects such as a greater international outlook and a widening of horizons within the academic institutions served by the libraries, as well as more meticulous planning by library authorities

    Global Stability Analysis of Turbulent Transonic Flows on Airfoil geometries

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    La aparición de inestabilidades en un flujo es un problema importante que puede afectar a algunas aplicaciones aerodinámicas. De hecho existen diferentes tipos de fenómenos no-estacionarios que actualmente son tema de investigación; casos como la separación a altos ángulos de ataque o el buffet transónico son dos ejemplos de cierta relevancia. El análisis de estabilidad global permite identificar la aparición de dichas condiciones inestables, proporcionando información importante sobre la región donde la inestabilidad es dominante y sobre la frecuencia del fenómeno inestable. La metodología empleada es capaz de calcular un flujo base promediado mediante una discretización con volúmenes finitos y posteriormente la solución de un problema de autovalores asociado a la linealización que aparece al perturbar el flujo base. El cálculo numérico se puede dividir en tres pasos: primero se calcula una solución estacionaria para las ecuaciones RANS, luego se extrae la matriz del Jacobiano que representa el problema linealizado y finalmente se deriva y se resuelve el problema de autovalores generalizado mediante el método iterativo de Arnoldi. Como primer caso de validación, la técnica descrita ha sido aplicada a un cilindro circular en condiciones laminares para detectar el principio de las oscilaciones de los vórtices de von Karman, y se han comparado los resultados con experimentos y cálculos anteriores. La parte más importante del estudio se centra en el análisis de flujos compresibles en régimen turbulento. La predicción de la aparición y la progresión de flujo separado a altos ángulos de ataque se han estudiado en el perfil NACA0012 en condiciones tanto subsónicas como supersónicas y en una sección del ala del A310 en condiciones de despegue. Para todas las geometrías analizadas, se ha podido observar que la separación gradual genera la aparición de un modo inestable específico para altos ángulos de ataque siempre mayores que el ángulo asociado al máximo coeficiente de sustentación. Además, se ha estudiado el problema adjunto para obtener información sobre la zona donde una fuerza externa provoca el máximo cambio en el campo fluido. El estudio se ha completado calculando el mapa de sensibilidad estructural y localizando el centro de la inestabilidad. En el presente trabajo de tesis se ha analizado otro importante fenómeno: el buffet transónico. En condiciones transónicas, la interacción entre la onda de choque y la capa límite genera una oscilación de la posición de la onda de choque y, por consiguiente, de las fuerzas aerodinámicas. El conocimiento de las condiciones críticas y su origen puede ayudar a evitar la oscilación causada por estas fuerzas. Las condiciones para las cuales comienza la inestabilidad han sido calculadas y comparadas con trabajos anteriores. Por otra parte, los resultados del correspondiente problema adjunto y el mapa de sensibilidad se han obtenido por primera vez para el buffet, indicando la región del dominio que sera necesario modificar para crear el mayor cambio en las propiedades del campo fluido. Dado el gran consumo de memoria requerido para los casos 3D, se ha realizado un estudio sobre la reducción del domino con la finalidad de reducirlo a la región donde está localizada la inestabilidad. La eficacia de dicha reducción de dominio ha sido evaluada investigando el cambio en la dimensión de la matriz del Jacobiano, no resultando muy eficiente en términos del consumo de memoria. Dado que el buffet es un problema en general tridimensional, el análisis TriGlobal de una geometría 3D podría considerarse el auténtico reto futuro. Como aproximación al problema, un primer estudio se ha realizado empleando una geometría tridimensional extruida del NACA00f2. El cálculo del flujo 3D y, por primera vez en casos tridimensionales compresibles y turbulentos, el análisis de estabilidad TriGlobal, se han llevado a cabo. La comparación de los resultados obtenidos con los resultados del anterior modelo 2D, ha permitido, primero, verificar la exactitud del cálculo 2D realizado anteriormente y también ha proporcionado una estimación del consumo de memoria requerido para el caso 3D. ABSTRACT Flow unsteadiness is an important problem in aerodynamic applications. In fact, there are several types of unsteady phenomena that are still at the cutting edge of research in the field; separation at high angles of attack and transonic buffet are two important examples. Global Stability Analysis can identify the unstable onset conditions, providing important information about the instability location in the domain and the frequency of the unstable phenomenon. The methodology computes a base flow averaged state based on a finite volume discretization and a solution for a generalized eigenvalue problem corresponding to the perturbed linearized equations. The numerical computation is then performed in three steps: first, a steady solution for the RANS equation is computed; second, the Jacobian matrix that represents the linearized problem is obtained; and finally, the generalized eigenvalue problem is derived and solved with an Arnoldi iterative method. As a first validation test, the technique has been applied on a laminar circular cylinder in order to detect the von Karman vortex shedding onset, comparing the results with experiments and with previous calculations. The main part of the study focusses on turbulent and compressible cases. The prediction of the origin and progression of separated flows at high angles of attack has been studied on the NACA0012 airfoil at subsonic and transonic conditions and for the A310 airfoil in take-off configuration. For all the analyzed geometries, it has been found that gradual separation generates the appearance of one specific unstable mode for angles of attack always greater than the ones related to the maximum lift coefficient. In addition, the adjoint problem has been studied to suggest the location of an external force that results in the largest change to the flow field. From the direct and the adjoint analysis the structural sensitivity map has been computed and the core of the instability has been located. The other important phenomenon analyzed in this work is the transonic buffet. In transonic conditions, the interaction between the shock wave and the boundary layer leads to an oscillation of the shock location and, consequently, of the aerodynamic forces. Knowing the critical operational conditions and its origin can be helpful in preventing such fluctuating forces. The instability onset has then been computed and compared with the literature. Moreover, results of the corresponding adjoint problem and a sensitivity map have been provided for the first time for the buffet problem, indicating the region that must be modified to create the biggest change in flow field properties. Because of the large memory consumption required when a 3D case is approached, a domain reduction study has been carried out with the aim of limiting the domain size to the region where the instability is located. The effectiveness of the domain reduction has been evaluated by investigating the change in the Jacobian matrix size, not being very efficient in terms of memory consumption. Since buffet is a three-dimensional problem, TriGlobal stability analysis can be seen as a future challenge. To approximate the problem, a first study has been carried out on an extruded three-dimensional geometry of the NACA0012 airfoil. The 3D flow computation and the TriGlobal stability analysis have been performed for the first time on a compressible and turbulent 3D case. The results have been compared with a 2D model, confirming that the buffet onset evaluated in the 2D case is well detected. Moreover, the computation has given an indication about the memory consumption for a 3D case

    Direct and adjoint global stability analysis of turbulent transonic flows over a NACA0012 profile

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    In this work, various turbulent solutions of the two-dimensional (2D) and three-dimensional compressible Reynolds averaged Navier?Stokes equations are analyzed using global stability theory. This analysis is motivated by the onset of flow unsteadiness (Hopf bifurcation) for transonic buffet conditions where moderately high Reynolds numbers and compressible effects must be considered. The buffet phenomenon involves a complex interaction between the separated flow and a shock wave. The efficient numerical methodology presented in this paper predicts the critical parameters, namely, the angle of attack and Mach and Reynolds numbers beyond which the onset of flow unsteadiness appears. The geometry, a NACA0012 profile, and flow parameters selected reproduce situations of practical interest for aeronautical applications. The numerical computation is performed in three steps. First, a steady baseflow solution is obtained; second, the Jacobian matrix for the RANS equations based on a finite volume discretization is computed; and finally, the generalized eigenvalue problem is derived when the baseflow is linearly perturbed. The methodology is validated predicting the 2D Hopf bifurcation for a circular cylinder under laminar flow condition. This benchmark shows good agreement with the previous published computations and experimental data. In the transonic buffet case, the baseflow is computed using the Spalart?Allmaras turbulence model and represents a mean flow where the high frequency content and length scales of the order of the shear-layer thickness have been averaged. The lower frequency content is assumed to be decoupled from the high frequencies, thus allowing a stability analysis to be performed on the low frequency range. In addition, results of the corresponding adjoint problem and the sensitivity map are provided for the first time for the buffet problem. Finally, an extruded three-dimensional geometry of the NACA0012 airfoil, where all velocity components are considered, was also analyzed as a Triglobal stability case, and the outcoming results were compared to the previous 2D limited model, confirming that the buffet onset is well detected

    Global Stability Analysis of a Compressible Turbulent Flow around a High-Lift Configuration

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    The purpose of this work is to analyze a complex high lift configuration for which significant regions of separated flow are present. Current state of the art methods have some diffculty to predict the origin and the progression of this separated flow when increasing the angle of attack. The mechanisms responsible for the maximum lift limit on multi-element wing con?gurations are not clear; this stability analysis could help to understand the physics behind the phenomenon and to find a relation between the flow separation and the instability onset. The methodology presented herein consists in the computation of a steady base flow solution based on a finite volume discretization and a proposal of the solution for a generalized eigenvalue problem corresponding to the perturbed and linearized problem. The eigenvalue problem has been solved with the Arnoldi iterative method, one of the Krylov subspace projection methods. The described methodology was applied to the NACA0012 test case in subsonic and in transonic conditions and, finally, for the first time to the authors knowledge, on an industrial multi-component geometry, such as the A310 airfoil, in order to identify low frequency instabilities related to the separation. One important conclusion is that for all the analyzed geometries, one unstable mode related to flow separation appears for an angle of attack greater than the one correspondent to the maximum lift coe?cient condition. Finally, an adjoint study was carried out in order to evaluate the receptivity and the structural sensitivity of the geometries, giving an indication of the domain region that could be modified resulting in the biggest change of the flowfield

    3-D Fibrin Scaffold Improves Stemness of Human Peripheral Blood Endothelial Progenitor Cells

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    Aims Fibrin is a natural biopolymer appealing for cell-based regenerative therapies, because it can support growth, migration and differentiation of different cell types. Endothelial progenitor cells (EPC) represent a very interesting alternative cell source for mature endothelial cells; the fact that can easily isolated from the peripheral blood, thereby eliminating donor morbidity, makes them ideal in applications in the field of regenerative medicine. We have demonstrated that fibrin can support EPC viability and growth. Aim of this study was to evaluate if fibrin can affect EPC differentiation and stem cell markers expression. Methods Fibrin was prepared mixing commercially available (Kedrion S.p.A. Lucca, Italy) fibrinogen (9 mg/ml) and thrombin (25 U/ml). Clot ultrastructure was investigated by scanning electron microscopy (SEM) and cryogenic SEM (CRYO-SEM) to measure fibre diameter and density. Clot elasticity was evaluated by atomic force microscopy (AFM), measuring the tip-sample force by cantilever displacement. EPC were obtained from peripheral blood and cultured on fibrin at the concentration of 1x106cell/cm2. Fibronectin coating was used as a control. Metabolic activity was assessed after 7 and 14 days by WST1 assay and viability by confocal microscopy (calcein incorporation). The expression of both endothelial (CD31, KDR, vWF, Ve-Cadherin) and stem cell markers (nanog, oct-4) was assessed by flow cytometry, confocal microscopy and Real Time RT-PCR. Results SEM analysis revealed a nanometric fibrous structure, with mean fiber diameter of 165?4 nm and mean density of 95.9?0.2 %. CRYO-SEM suggested a reticulate structure with mesh-size up to 10 ?m. Fibrin clot elasticity was 1.78 MPa, as in literature. WST1 assay showed that fibrin increased EPC metabolic activity as compared to fibronectin (fibrin: 0.606?0.056 a.u. vs. fibronectin: 0.311?0.067). Calcein staining demonstrated that EPC were still viable at 14 days. Flow cytometry showed the expression of endothelial markers (CD31=41.8?8.4%; vWF=32.3?3.0%; KDR=89.3?3.7%; VE-Cadherin=41.2?3.8%), confirmed also by confocal microscopy and Real Time RT-PCR. Interestingly, nanog and oct-4 (embryonic stem cell markers) expression was significantly greater on fibrin (p<0.001) as compared to fibronectin. Conclusions These findings suggest that fibrin it is not only a suitable scaffold for EPC growth and viability but also induces EPC differentiation. The observation that Nanog, known as the most important marker of stemness, is maintained longer than on fibronectin, may offer a surplus value to stem cell-based therapies

    Il deposito legale regionale in Italia: stato dell’arte e risultati di una recente indagine

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    The article sets out the results of the survey conducted between October and November 2019 by the Commissione nazionale biblioteche e servizi nazionali of the AIB on Regional Legal Deposit, fifteen years after the last field research on the same subject. The Regional Legal Deposit was established by Law 106/2004 and regulated by Presidential Decree 252/2006 and two ministerial decrees of 2007 and 2009. This set of rules provides that each publisher should send several copies of its publications to certain libraries in the Region where the publishing houses are based to create a regional archive of the Italian editorial production. Regional Legal Deposit is one of the most innovative, albeit most critical and lesser-known, aspects of legal deposit regulation. In the first phase of the investigation, it was decided to make an accurate analysis of the information released by the libraries themselves, which made it possible to photograph the reality of the regional depository libraries in Italy, partially changed since 2009. The second phase of the survey consisted of an online questionnaire addressed to depository libraries, divided into nine questions – each of which included three closed responses and the opportunity to leave a comment. The survey, which obtained a good degree of participation (62%), showed a somewhat similar situation to the past, highlighting the problems of insufficient storage space, insufficient staff, lack of resources and excessive dependence on local policies. However, some of the answers to the questionnaire are encouraging: publications are sent with a certain regularity, the Regional Legal Deposit is perceived as an obligation that has also positive aspects and checks are carried out on its fulfillment. In addition emerges the importance of setting up a unified publisher database, which could facilitate the management of the Legal Deposit and provide a starting point for future synergies

    MALAT1 as a Regulator of the Androgen-Dependent Choline Kinase A Gene in the Metabolic Rewiring of Prostate Cancer

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    Simple Summary Despite the rapid advance in cancer therapies, treatment-resistant relapse remains a significant challenge in cancer treatment. Acquired resistance arises during or after treatment administration, and is usually the main contributor to relapse. For example, prostate cancer, the most frequent type of cancer in the elderly male population, frequently develops into aggressive forms resistant to chemical and hormonal therapies. In this condition, the so-called "cholinic phenotype" that is characterized by the overexpression of choline kinase alpha (CHKA) and increased phosphocholine levels leads to aberrant lipid metabolism. Our work demonstrates that CHKA, which is necessary for membrane phospholipid synthesis, is a target of the long non-coding RNA MALAT1. This study helps to further decipher how MALAT1 affects the regulation of crucial phospholipid/sphingolipid metabolic enzymes, as well as how the androgen receptor pathway is involved in MALAT1-dependent transcriptional regulation. Background. Choline kinase alpha (CHKA), an essential gene in phospholipid metabolism, is among the modulated MALAT1-targeted transcripts in advanced and metastatic prostate cancer (PCa). Methods. We analyzed CHKA mRNA by qPCR upon MALAT1 targeting in PCa cells, which is characterized by high dose-responsiveness to the androgen receptor (AR) and its variants. Metabolome analysis of MALAT1-depleted cells was performed by quantitative High-resolution 1 H-Nuclear Magnetic Resonance (NMR) spectroscopy. In addition, CHKA genomic regions were evaluated by chromatin immunoprecipitation (ChIP) in order to assess MALAT1-dependent histone-tail modifications and AR recruitment. Results. In MALAT1-depleted cells, the decrease of CHKA gene expression was associated with reduced total choline-containing metabolites compared to controls, particularly phosphocholine (PCho). Upon MALAT1 targeting a significant increase in repressive histone modifications was observed at the CHKA intron-2, encompassing relevant AR binding sites. Combining of MALAT1 targeting with androgen treatment prevented MALAT1-dependent CHKA silencing in androgen-responsive (LNCaP) cells, while it did not in hormone-refractory cells (22RV1 cells). Moreover, AR nuclear translocation and its activation were detected by confocal microscopy analysis and ChIP upon MALAT1 targeting or androgen treatment. Conclusions. These findings support the role of MALAT1 as a CHKA activator through putative association with the liganded or unliganded AR, unveiling its targeting as a therapeutic option from a metabolic rewiring perspective

    Immune inflammation indicators in anal cancer patients treated with concurrent chemoradiation: training and validation cohort with online calculator (ARC: Anal Cancer Response Classifier)

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    Background: In anal cancer, there are no markers nor other laboratory indexes that can predict prognosis and guide clinical practice for patients treated with concurrent chemoradiation. In this study, we retrospectively investigated the influence of immune inflammation indicators on treatment outcome of anal cancer patients undergoing concurrent chemoradiotherapy. Methods: All patients had a histologically proven diagnosis of squamous cell carcinoma of the anal canal/margin treated with chemoradiotherapy according to the Nigro's regimen. Impact on prognosis of pre-treatment systemic index of inflammation (SII) (platelet x neutrophil/lymphocyte), neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were analyzed. Results: A total of 161 consecutive patients were available for the analysis. Response to treatment was the single most important factor for progression-free survival (PFS) and overall survival (OS). At univariate analysis, higher SII level was significantly correlated to lower PFS (p&lt;0.01) and OS (p=0.046). NLR level was significantly correlated to PFS (p=0.05), but not to OS (p=0.06). PLR level significantly affected both PFS (p&lt;0.01) and OS (p=0.02). On multivariate analysis pre-treatment, SII level was significantly correlated to PFS (p=0.0079), but not to OS (p=0.15). We developed and externally validated on a cohort of 147 patients a logistic nomogram using SII, nodal status and pre-treatment Hb levels. Results showed a good predictive ability with C-index of 0.74. An online available calculator has also been developed. Conclusion: The low cost and easy profile in terms of determination and reproducibility make SII a promising tool for prognostic assessment in this oncological setting

    Targeted gene panel screening is an effective tool to identify undiagnosed late onset Pompe disease

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    Mutations in the GAA gene may cause a late onset Pompe disease presenting with proximal weakness without the characteristic muscle pathology, and therefore a test for GAA activity is the first tier analysis in all undiagnosed patients with hyperCKemia and/or limb-girdle muscular weakness. By using MotorPlex, a targeted gene panel for next generation sequencing, we analyzed GAA and other muscle diseasegenes in a large cohort of undiagnosed patients with suspected inherited skeletal muscle disorders (n = 504). In this cohort, 275 patients presented with limb-girdle phenotype and/or an isolated hyperCKemia. Mutational analysis identified GAA mutations in ten patients. Further seven affected relatives were identified by segregation studies. All the patients carried the common GAA mutation c.-32-13T > G and a second, previously reported mutation. In the subcohort of 275 patients with proximal muscle weakness and/or hyperCKemia, we identified late-onset Pompe disease in 10 patients. The clinical overlap between Pompe disease and LGMDs or other skeletal muscle disorders suggests that GAA and the genes causing a metabolic myopathy should be analyzed in all the gene panels used for testing neuromuscular patients. However, enzymatic tests are essential for the interpretation and validation of genetic results. (C) 2018 Elsevier B.V. All rights reserved.Peer reviewe

    Next Generation Molecular Diagnosis of Hereditary Spastic Paraplegias: An Italian Cross-Sectional Study

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    Hereditary spastic paraplegia (HSP) refers to a group of genetically heterogeneous neurodegenerative motor neuron disorders characterized by progressive age-dependent loss of corticospinal motor tract function, lower limb spasticity, and weakness. Recent clinical use of next generation sequencing (NGS) methodologies suggests that they facilitate the diagnostic approach to HSP, but the power of NGS as a first-tier diagnostic procedure is unclear. The larger-than-expected genetic heterogeneity-there are over 80 potential disease-associated genes-and frequent overlap with other clinical conditions affecting the motor system make a molecular diagnosis in HSP cumbersome and time consuming. In a single-center, cross-sectional study, spanning 4 years, 239 subjects with a clinical diagnosis of HSP underwent molecular screening of a large set of genes, using two different customized NGS panels. The latest version of our targeted sequencing panel (SpastiSure3.0) comprises 118 genes known to be associated with HSP. Using an in-house validated bioinformatics pipeline and several in silico tools to predict mutation pathogenicity, we obtained a positive diagnostic yield of 29% (70/239), whereas variants of unknown significance (VUS) were found in 86 patients (36%), and 83 cases remained unsolved. This study is among the largest screenings of consecutive HSP index cases enrolled in real-life clinical-diagnostic settings. Its results corroborate NGS as a modern, first-step procedure for molecular diagnosis of HSP. It also disclosed a significant number of new mutations in ultra-rare genes, expanding the clinical spectrum, and genetic landscape of HSP, at least in Italy
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