22 research outputs found

    Effect of noise in the time-frequency estimate of the peridynamic bond elastic constant parameter

    Get PDF
    The Peridynamic (PD) theory is a modern nonlocal (nonlinear, elastic /inelastic, with-out/with memory) theory able to deal with long-range forces and discontinuity in materials. For this reason the theory is suitable for the monitoring of masonry structures. Starting from a special case of PD formulation, named Bond-Based Peridynamic (BBPD), a feature ob-tained by the idealization of real systems with BBPD is used for SHM purposes: the bond elastic constant parameter. To characterize the damage (i.e. permanent deterioration of ma-terial and/or geometric properties of the systems) occurring in systems idealized with PD models, a joint time-frequency direct estimate of the parameter values is performed using a Short Time Fourier Transform (STFF) of the systems response and the input acceleration at the base of the systems. The method is applied numerically and the effect of noise in the time-frequency evaluation of the parameter values is analyzed. The study concludes that PD can provides simply and strong information on the health of simulated systems, allowing at the same time an easy and scalable parametrization of civil, especially masonry, structures, while the bond elastic constant parameter can be used for the damage characterization, i.e. to detect, quantify and localize the damage in a generic system

    Combining satellite geophysical data with continuous on-site measurements for monitoring the dynamic parameters of civil structures

    Get PDF
    One key issue in the Structural Health Monitoring (SHM) of buildings is the influence of the soil on the dynamics of the system. The lack of accurate information on soil-structure interaction represents a source of significant uncertainty and generates difficulties in assessing the state of structural health. In this respect, satellite data could represent a valuable tool for soil knowledge. This paper presents the first study of satellite data coming from the environmental Copernicus program of the European Space Agency (ESA) for the alternative application in the field of SHM. In particular, Land Surface Temperature (LST) and Soil Water Index (SWI) data are elected to study surface temperature and moisture condition of the soil. Once examined and processed, these records have been statistically analyzed, crossed with on-site experimental quantities (natural frequencies and environmental variations), and given as input to a Finite Element (FE) model. The final goal is to understand the actual structural behavior, but also to monitor the evolution of the dynamic parameters for the purposes of structural and seismic monitoring. The largest oval masonry dome in the world was chosen as a prominent case study to demonstrate this novel approach to SHM

    Detailed Analysis of ITPR1 Missense Variants Guides Diagnostics and Therapeutic Design

    Get PDF
    BACKGROUND: The ITPR1 gene encodes the inositol 1,4,5-trisphosphate (IP3 ) receptor type 1 (IP3 R1), a critical player in cerebellar intracellular calcium signaling. Pathogenic missense variants in ITPR1 cause congenital spinocerebellar ataxia type 29 (SCA29), Gillespie syndrome (GLSP), and severe pontine/cerebellar hypoplasia. The pathophysiological basis of the different phenotypes is poorly understood. OBJECTIVES: We aimed to identify novel SCA29 and GLSP cases to define core phenotypes, describe the spectrum of missense variation across ITPR1, standardize the ITPR1 variant nomenclature, and investigate disease progression in relation to cerebellar atrophy. METHODS: Cases were identified using next-generation sequencing through the Deciphering Developmental Disorders study, the 100,000 Genomes project, and clinical collaborations. ITPR1 alternative splicing in the human cerebellum was investigated by quantitative polymerase chain reaction. RESULTS: We report the largest, multinational case series of 46 patients with 28 unique ITPR1 missense variants. Variants clustered in functional domains of the protein, especially in the N-terminal IP3 -binding domain, the carbonic anhydrase 8 (CA8)-binding region, and the C-terminal transmembrane channel domain. Variants outside these domains were of questionable clinical significance. Standardized transcript annotation, based on our ITPR1 transcript expression data, greatly facilitated analysis. Genotype-phenotype associations were highly variable. Importantly, while cerebellar atrophy was common, cerebellar volume loss did not correlate with symptom progression. CONCLUSIONS: This dataset represents the largest cohort of patients with ITPR1 missense variants, expanding the clinical spectrum of SCA29 and GLSP. Standardized transcript annotation is essential for future reporting. Our findings will aid in diagnostic interpretation in the clinic and guide selection of variants for preclinical studies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

    Evaluating the SERCA2 and VEGF mRNAs as Potential Molecular Biomarkers of the Onset and Progression in Huntington's Disease

    Get PDF
    Abnormalities of intracellular Ca2+ homeostasis and signalling as well as the down-regulation of neurotrophic factors in several areas of the central nervous system and in peripheral tissues are hallmarks of Huntington\u2019s disease (HD). As there is no therapy for this hereditary, neurodegenerative fatal disease, further effort should be made to slow the progression of neurodegeneration in patients through the definition of early therapeutic interventions. For this purpose, molecular biomarker(s) for monitoring disease onset and/or progression and response to treatment need to be identified. In the attempt to contribute to the research of peripheral candidate biomarkers in HD, we adopted a multiplex real-time PCR approach to analyse the mRNA level of targeted genes involved in the control of cellular calcium homeostasis and in neuroprotection. For this purpose we recruited a total of 110 subjects possessing the HD mutation at different clinical stages of the disease and 54 sex- and agematched controls. This study provides evidence of reduced transcript levels of sarco-endoplasmic reticulum-associated ATP2A2 calcium pump (SERCA2) and vascular endothelial growth factor (VEGF) in peripheral blood mononuclear cells (PBMCs) of manifest and premanifest HD subjects. Our results provide a potentially new candidate molecular biomarker for monitoring the progression of this disease and contribute to understanding some early events that might have a role in triggering cellular dysfunctions in HD

    Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia

    Get PDF

    Branch Retinal Artery Occlusion after Percutaneous Coronary Intervention

    No full text
    We report a case of branch retinal artery occlusion (BRAO) that occurred after percutaneous coronary intervention (PCI). A 59-year-old man with no other previous diseases presented visual acuity deterioration in the left eye 24 hours after PCI. Fundus examination revealed ischemia at the temporal branch of the retinal artery associated with inner layer edema. Prompt treatment was performed with ocular digital massage and paracentesis of the anterior chamber. However, at discharge, the patient had a persistent visual loss with a central scotoma that persisted at 35-day follow-up without improvement of the visual acuity. The patient did not suffer from any other systemic complications. Retinal infarction should be considered a potential complication of PCI. Patients and health care providers should be aware of any visual signs. Permanent visual disability can be prevented by immediate diagnosis and prompt intervention

    Health Potential of Aloe vera against Oxidative Stress Induced Corneal Damage: An “In Vitro” Study

    No full text
    Fuchs endothelial corneal dystrophy (FECD) is characterized by the gradual deterioration of corneal endothelial cells (CECs) and is the most common cause of corneal transplantation worldwide. CECs apoptosis caused by oxidative stress plays a pivotal role in the pathogenesis of FECD. Antioxidant compounds have been of considerable significance as a candidate treatment in the management of corneal diseases. Based on these findings, the objective of this study was to evaluate the effects of an aloe extract with antioxidant properties, in an “in vitro” model of FECD. Human corneal epithelial (HCE) cells were preincubated with aloe extract 100 μg/mL, two hours before hydrogen peroxide (H2O2) stimulus. H2O2 challenge significantly reduced the cell viability, increased the generation of Reactive Oxygen Species (ROS) and malondialdehyde levels. Moreover, m-RNA expression and activity of Nrf-2, Catalase and Superoxide dismutase (SOD) were reduced together with an enhanced expression of IL-1β, tumor necrosis factor-α (TNF-α), IL-6, and cyclooxygenase 2 (COX-2). Furthermore, Bcl-2, Caspase-3 and Caspase-8 expression were down-regulated while Bax was up-regulated by H2O2 stimulus. Aloe extract blunted the oxidative stress-induced inflammatory cascade triggered by H2O2 and modulated apoptosis. Aloe extract defends HCE cells from H2O2-induced injury possibly due its antioxidant and anti-inflammatory activity, indicating that eye drops containing aloe extract may be used as an adjunctive treatment for FECD

    Sensitivity Analysis of the Environmental Effect on the Dynamics of Concrete Historical Architectures with Structural Joints

    No full text
    A large part of the 20th century architectural heritage is approaching the end of its useful service life and issues related to its conservation should be therefore addressed. In that period, the use of concrete as a building material spread considerably, favoring experimentation in geometries and structural schemes. If on one hand the innovativeness and uniqueness of these buildings have made them an essential part of our architectural heritage, on the other hand they make their study challenging. The complexity of these structures' dynamic behavior results in the uncertainty on the sensitivity to possible damage scenarios and environmental factors, which represent a relevant aspect in Structural Health Monitoring (SHM). This paper reports the results of a sensitivity analysis of changing environmental conditions on a concrete historical building, composed by blocks divided by structural joints. The case study is the Pavilion V of Turin Exhibition Center, built by Riccardo Morandi in the late 50s. The research conducted on the pavilion's Finite Element Model (FEM) allowed to show the effects of the variation of the elastic modulus of the structure's components on the modal parameters for different temperature sensitivity scenarios and, consequently, to extract useful information for an upcoming permanent monitoring

    Thermomechanical model updating of the world’s largest oval dome

    No full text
    Model updating of monumental buildings is usually performed based on the results of experimental modal analysis campaigns. In this paper, we present a different strategy for model calibration, which is realised on data acquired by a permanent static monitoring system. When both mechanical and environmental (temperature) data set are available, a thermomechanical model updating can be executed. This study contains the results of a thermomechanical Finite Element Model (FEM) updating conducted on the “Regina Montis Regalis” dome, in Vicoforte (Italy)

    Update on the Classification and Pathophysiological Mechanisms of Pediatric Cardiorenal Syndromes

    No full text
    Cardiorenal syndrome (CRS) is defined as a disorder resulting from the abnormal interaction between the heart and kidney, in which acute or chronic dysfunction of one organ may lead to acute and/or chronic dysfunction of the other. The functional interplay between the heart and kidney is characterized by a complex bidirectional symbiotic interaction, regulated by a wide array of both genetic and environmental mechanisms. There are at least five known subtypes of CRS, based on the severity of clinical features and the degree of heart/renal failure. The fourth subtype (cardiorenal syndrome type 4 (CRS4)) is characterized by a primary chronic kidney disease (CKD), which in turn leads to a decreased cardiac function. Impairment of renal function is among the most important pathophysiological factors contributing to heart failure (HF) in the pediatric age group, and cardiovascular complications could be one of the most important causes of mortality in pediatric patients with advanced CKD. In this context, a loss of glomerular filtration rate directly correlates with both the progression of cardiovascular complications in CRS and the risk of HF. This review describes the interaction pathways between the heart and kidney and the recently identified pathophysiological mechanisms underlying pediatric CRS, with a special focus on CRS4, which encompasses both primary CKD and cardiovascular disease (CVD)
    corecore