Masonry cross vaults: an overview of the historical developments

The cross vault represents one of the most diffused and fascinating structural typologies of the European architectural heritage. Its history began almost two thousand years ago and reached a widespread use during the Middle Ages with the outstanding gothic cathedrals. Without any proper scientific support but only using trial-and-error methods, considering each building as a scaled specimen of a new one to be built, the ancient workmanship achieved a proper competence represented by the so-called rules of thumb. However, despite this long-lasting history, it is only from the eighteenth centuries that scholars have tried to tackle the problem of analytically describing its structural behaviour. In this regard, the first part of the present study is devoted to the evolution of cross vaults from the geometrical and constructive standpoint, whereas the second one describes the historical advancements of its structural behaviour, until the development of modern limit analysis

Seismic performance of masonry cross vaults: learning from historical developments and experimental testing

Considering the seismic behaviour of cultural heritage buildings, an influential role is played by masonry vaults, often representing the most vulnerable part of the construction. Despite their long-lasting history and the damage observation following the Italian earthquakes of the recent past, research in this area is still limited. In this regard, the present thesis is devoted to the study of the seismic behaviour of masonry groin vaults, considered as one of the most diffused vault type in European seismic prone areas in cloisters, palaces and churches. Groin vaults are resulting from the intersection at a right angle of two semi-cylindrical shells on a square bay, and can be addressed as the simplest form of cross vaults, defined as a combination (compound) of curved shells whose thrust converges along the diagonals to isolated abutments. The goal of this work is met via an integration of laboratory tests and numerical analyses. The first part of the thesis reviews the historical developments of the cross vault, the structural methods adopted by the scientific community and the damage evidences after laboratory experiments and post-seismic observation. The subsequent part deals with shaking table tests on a scaled arch built with dry-joint 3D printed voussoirs. The experimental campaign had a twofold purpose. On the one hand it gave insight into the seismic behaviour of masonry arches and, on the other hand, thanks to the tracking motion system employed to record the tests, it provided valuable information to calibrate a three-dimensional numerical model. The physical model was studied using a commercially available FEM software, namely DIANA (from TNO Delft), assuming rigid-infinitely resistant blocks and Coulomb friction interfaces. The nonlinear analyses regarded both the static and dynamic behaviour, shading light on the influence of interface stiffness and damping. The numerical model was subsequently extended to the study of the three-dimensional behaviour of groin vaults. In particular, the analyses focused on the results available in literature following a recent experimental campaign on a 1:5 scaled vault. The model was able to properly catch the maximum strength and the failure mechanism recorded in the quasi-static tests. Analogies between the nonlinear behaviour of the vault and the free-standing rigid block undergoing incremental horizontal force are also discussed. The last part of the thesis is dedicated to a sensitivity analysis aimed at evaluating the influence of the main geometrical and mechanical parameters on the seismic capacity and failure mechanisms of groin vaults. A non-commercial code implemented in Matlab, based on the upper bound approach of standard limit analysis, was used. The results were finally processed through a multiple linear regression analysis in order to get simplified analytical equations for expedite seismic evaluation of existing groin vaults

A parametric investigation on the seismic capacity of masonry cross vaults

Considering the relevance and the artistic value of cross vaults in European seismic prone areas, a parametric study on the seismic capacity of this element is presented. In particular, the behaviour of the so-called groin vault is discussed, i.e. intersection at a right angle of two semi-circular barrel vaults. The influence of span, rise, thickness, infill, and masonry tensile strength is investigated with respect to two boundary conditions, representative of typical vault configurations within heritage buildings. The analyses were performed using an upper bound approach of standard limit analysis. For the sake of clarity, the adopted code framework is briefly reviewed.With the aim of identifying the most frequent failure mechanisms, the outcomes of the parametric analysis have been visually inspected and sorted according to the input parameters. Aiming toward a simplified assessment criterion, the resulting list of parameters was subsequently processed through multiple linear regression analyses that can help practitioners in quick seismic evaluation.This work was partly financed by FEDER funds through the Competitivity Factors Operational Programme - COMPETE and by national funds through FCT - Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007633.info:eu-repo/semantics/publishedVersio

The role of endocannabinoid signaling in the molecular mechanisms of neurodegeneration in Alzheimer's disease

Alzheimer's disease (AD) is the most common form of progressive neurodegenerative disease characterized by cognitive impairment and mental disorders. The actual cause and cascade of events in the progression of this pathology is not fully determined. AD is multifaceted in nature and is linked to different multiple mechanisms in the brain. This aspect is related to the lack of efficacious therapies that could slow down or hinder the disease onset/progression. The ideal treatment for AD should be able to modulate the disease through multiple mechanisms rather than targeting a single dysregulated pathway. Recently, the endocannabinoid system emerged as a novel potential therapeutic target to treat AD. In fact, exogenous and endogenous cannabinoids seem to be able to modulate multiple processes in AD, although the mechanisms that are involved are not fully elucidated. This review provides an update of this area. In this review, we recapitulate the role of endocannabinoid signaling in AD and the probable mechanisms through which modulators of the endocannabinoid system provide their effects, thus highlighting how this target might provide more advantages over other therapeutic targets

Altered Expression of the CB1 Cannabinoid Receptor in the Triple Transgenic Mouse Model of Alzheimer's Disease

The endocannabinoid system has gained much attention as a new potential pharmacotherapeutic target in various neurodegenerative diseases, including Alzheimer's disease (AD). However, the association between CB1 alterations and the development of AD neuropathology is unclear and often contradictory. In this study, brain CB1 mRNA and CB1 protein levels were analyzed in 3 × Tg-AD mice and compared to wild-type littermates at 2, 6 and 12 months of age, using in-situ hybridization and immunohistochemistry, respectively. Semiquantitative analysis of CB1 expression focused on the prefrontal cortex (PFC), prelimbic cortex, dorsal hippocampus (DH), basolateral amygdala complex (BLA), and ventral hippocampus (VH), all areas with high CB1 densities that are strongly affected by neuropathology in 3 × Tg-AD mice. At 2 months of age, there was no change in CB1 mRNA and protein levels in 3 × Tg-AD mice compared to Non-Tg mice in all brain areas analyzed. However, at 6 and 12 months of age, CB1 mRNA levels were significantly higher in PFC, DH, and BLA, and lower in VH in 3 × Tg-AD mice compared to wild-type littermates. CB1 immunohistochemistry revealed that CB1 protein expression was unchanged in 3 × Tg-AD at 2 and 6 months of age, while a significant decrease in CB1 receptor immunoreactivity was detected in the BLA and DH of 12-month-old 3 × Tg-AD mice, with no sign of alteration in other brain areas. The altered CB1 levels appear, rather, to be age-and/or pathology-dependent, indicating an involvement of the endocannabinoid system in AD pathology and supporting the ECS as a potential novel therapeutic target for treatment of AD

Dal team accoglienza al bed management ospedaliero.

RIASSUNTOLa riduzione dei posti letto negli ospedali laziali, ha ri-disegnato il concetto di servizio sanitario ospedaliero regionale, riconoscendo l'ospedale il solo luogo dove recarsi per curare le malattie acute ed urgenti. L'Azienda Ospedaliera San Camillo-Forlanini di Roma, nel rispetto del piano sanitario regionale, del piano di rientro e della riqualificazione della rete ospedaliera, ha avuto una significativa riduzione di posti letto e ciò, ha comportato una riorganizzazione interna. La Direzione Aziendale per dare una risposta soddisfacente all'utenza, ha dato inizio nel febbraio del 2008 ad un progetto, oggi servizio, con l'istituzione di un gruppo di coordinatori infermieristici, con lo specifico mandato di razionalizzare ed ottimizzare i posti letto dedicati all'emergenza-urgenza. Questo gruppo denominato "Team Accoglienza" è formato da caposala esperti, che conoscono il funzionamento dell'intero ospedale. Il team collabora, quotidianamente, con il personale medico ed infermieristico del Pronto Soccorso, per la definizione del percorso diagnostico, terapeutico ed assistenziale più idoneo al malato. Il progetto è stato sviluppato applicando la metodologia: del Percorso di Massima di Riferimento e l'Analisi Sistemica. Negli anni questo servizio ha contribuito: al miglioramento di alcuni indicatori sistemici di attivití , di alcune Unití  Operative ed alla formazione di personale sanitario di direzione. Nel 2009 la Giunta Regionale del Lazio ha riconosciuto tale progetto come strategico all'interno delle organizzazioni ospedaliere pubbliche e private.Parole Chiave: Bed Manager, ricovero, ottimizzatore.ABSTRACTReduction on number of hospital beds i.e. on patients' admission among hospitals in Lazio has lead to a reformulation of health service framework within Lazio indentifying hospital as the only place to go to treat acute and urgent diseases. San Camillo-Forlanini, the largest hospital in Rome, according to the regional health plan, the recovery plan and the redevelopment of network hospital has had a significant reduction of hospital beds leading, as consequence, to the need of an internal reorganization. In order to correctly address this issue, the management of the Hospital started in February 2008 a project, setting up a group made up by nursing coordinators which had as a main aim to manage the number of hospital beds needed for emergencies. This group has been called "Admission Team" and nurses within the group are familiar with hospital policies and organization. The team collaborates daily with physicians and nurses in emergency room, in order to decide the most appropriate health care protocol for each patient. The project follows a specific methodology i.e. Systemic Analysis. Over the years this project has contributed to the improvement to a number of indicators and more generally to the health care within the hospital together with the enhancement of education of new managerial roles among health professional. In 2009, the Regional Council of Lazio has recognized this project as strategic within private and public hospitals. Keywords: Bed Management, admission, hospital polic

Depressive-like behavior is paired to monoaminergic alteration in a murine model of Alzheimer's disease

BACKGROUND: Neuropsychiatric signs are critical in primary caregiving of Alzheimer patients and have not yet been fully investigated in murine models. METHODS: 18-month-old 3×Tg-AD male mice and their wild-type male littermates (non-Tg) were used. The open field test and the elevated plus maze test were used to evaluate anxiety-like behaviors, whereas the Porsolt forced swim test, the tail suspension test, and the sucrose preference test for antidepressant/depression-coping behaviors. Neurochemical study was conducted by microdialysis in freely-moving mice, analyzing the basal and K(+)-stimulated monoamine output in the frontal cortex and ventral hippocampus. Moreover by immunohistochemistry, we analysed the expression of Tyrosin hydroxylase and Tryptophan hydroxylase, which play a key role in the synthesis of monoamines. RESULTS: Aged 3×Tg-AD mice exhibited a higher duration of immobility in the forced swim and tail suspension tests (predictors of depression-like behavior) which was not attenuated by a noradrenaline reuptake inhibitor, desipramine. In the sucrose preference test, 3×Tg-AD mice showed a significantly lower sucrose preference compared to the non-Tg group, without any difference in total fluid intake. In contrast, the motor functions and anxiety-related emotional responses of 3×Tg-AD mice were normal, as detected by the open-field and elevated plus-maze tests. To strengthen these results, we then evaluated the monoaminergic neurotransmissions by in vivo microdialysis and immunohistochemistry. In particular, with the exception of the basal hippocampal dopamine levels, 3×Tg-AD mice exhibited a lower basal extracellular output of amines in the frontal cortex and ventral hippocampus and also a decreased extracellular response to K(+) stimulation. Such alterations occur with obvious local amyloid-β and tau pathologies and without gross alterations in the expression of Tyrosin and Tryptophan hydroxylase. CONCLUSIONS: These results suggest that 3×Tg-AD mice exhibit changes in depression-related behavior involving aminergic neurotrasmitters and provide an animal model for investigating AD with depression

PDIA3 expression is altered in the limbic brain regions of triple-transgenic mouse model of Alzheimer's disease

In the present study, we used a mouse model of Alzheimer's disease (AD) (3×Tg-AD mice) to longitudinally analyse the expression level of PDIA3, a protein disulfide isomerase and endoplasmic reticulum (ER) chaperone, in selected brain limbic areas strongly affected by AD-pathology (amygdala, entorhinal cortex, dorsal and ventral hippocampus). Our results suggest that, while in Non-Tg mice PDIA3 levels gradually reduce with aging in all brain regions analyzed, 3×Tg-AD mice showed an age-dependent increase in PDIA3 levels in the amygdala, entorhinal cortex, and ventral hippocampus. A significant reduction of PDIA3 was observed in 3×Tg-AD mice already at 6 months of age, as compared to age-matched Non-Tg mice. A comparative immunohistochemistry analysis performed on 3×Tg-AD mice at 6 (mild AD-like pathology) and 18 (severe AD-like pathology) months of age showed a direct correlation between the cellular level of Aβ and PDIA3 proteins in all the brain regions analysed, even if with different magnitudes. Additionally, an immunohistochemistry analysis showed the presence of PDIA3 in all post-mitotic neurons and astrocytes. Overall, altered PDIA3 levels appear to be age- and/or pathology-dependent, corroborating the ER chaperone's involvement in AD pathology, and supporting the PDIA3 protein as a potential novel therapeutic target for the treatment of AD

Antithrombotic Therapy in Hereditary Hemorrhagic Telangiectasia: Real-World Data from the Gemelli Hospital HHT Registry

Although Hereditary Hemorrhagic Telangiectasia (HHT) is characterized by an overwhelming bleeding propensity, patients with this disease may also present medical conditions that require antithrombotic therapy (AT). However, precise information on indications, dosage, duration, effectiveness, and safety of AT in HHT patients is lacking. We performed a retrospective analysis of the HHT Registry of our University Hospital and found 26 patients who received AT for a total of 30 courses (19 courses of anticoagulant therapy and 11 courses of antiplatelet therapy). Indications to treatments included: atrial fibrillation, venous thrombosis and pulmonary embolism, heart valve replacement, retinal artery occlusion, secondary prevention after either stroke or myocardial infarction, and thromboprophylaxis for surgery. The total time of exposure to antiplatelet therapy was 385 months and to anticoagulant therapy 169 months. AT was generally well tolerated, with no fatal bleedings and no significant changes in hemoglobin levels. However, we found three major bleedings, with an incidence rate of 6.5 per 100 patients per year. When only patients treated with anticoagulants were considered, the incidence rate of major bleedings increased to 21.6 per 100 patients per year. Our study indicates that major bleeding may occur in HHT patients receiving AT, with a substantially increased rate in those treated with anticoagulants. Further studies are needed to fully estimate the tolerability of antithrombotic drugs in HHT

Shaking table tests and numerical analyses on a scaled dry-joint arch undergoing windowed sine pulses

The damages occurred during recent seismic events have emphasised the vulnerability of vaulted masonry structures, one of the most representative elements of worldwide cultural heritage. Although a certain consensus has been reached regarding the static behaviour of masonry arches, still more efforts are requested to investigate their dynamic behaviour. In this regard, the present paper aims to investigate the performance of a scaled dry-joint arch undergoing windowed sine pulses. A feature tracking based measuring technique was employed to evaluate the displacement of selected points, shading light on the failure mechanisms and gathering data for the calibration of the numerical model. This was built according to a micro-modelling approach of the finite element method, with voussoirs assumed very stiff and friction interface elements. Comparisons with existing literature are also stressed, together with comments about scale effects.This work was partly financed by FEDER funds through the Competitivity Factors Operational Programme-COMPETE and by national funds through FCT-Foundation for Science and Technology within the scope of the Project POCI-01-0145-FEDER-007633.info:eu-repo/semantics/publishedVersio