Search results for " Models"
showing 10 items of 4240 documents
Numerical prediction of turbulent flow and heat transfer in helically coiled pipes
2010
Abstract Computational results were obtained for turbulent flow and heat transfer in curved pipes, representative of helically coiled heat exchangers. Following a grid refinement study, grid independent predictions from alternative turbulence models ( k – ɛ , SST k – ω and RSM– ω ) were compared with DNS results and experimental pressure drop and heat transfer data. Using the SST k – ω and RSM– ω models, pressure drop results were in excellent agreement with literature data and the Ito correlation. For heat transfer, the literature is not comparably complete or accurate, but a satisfactory agreement was obtained in the range of available data. Unsatisfactory results, both for pressure drop …
Performance of a historical cantilever reinforced concrete bridge with half-joint degradation
2022
The lack of maintenance of roadway concrete bridges built from the Second World War until the 70 s of the 20th century has led in recent years to an ever-increasing request for safety assessments. When bridge performance in terms of Serviceability Limit State (SLS) and Ultimate Limit State (ULS) has to be evaluated, in-situ visual inspections and load tests for safety and maintenance assessment have to be coupled with structural analysis. In order to identify a sound bridge structural model and to assess the actual conservation state, more refined models than those usually considered for section and reinforcement design should be used to reproduce the results of load tests and perform globa…
Limit theorems and price changes in financial markets
1998
Abstract We discuss the relation between limit theorems in probability theory and price change statistics in financial markets. An analysis of the published empirical results and theoretical models show that the problem of the statistical properties of price (or index) changes is still open. By using the limit theorems of probability theory and the current assumption that stock prices are well described by martingales, we point out that the probability density function (PDF) of price changes is expected to belong to theclass of infinitely divisible PDFs.
HUMAN LEUKOCYTE ANTIGEN POLYMORPHISMS IN ITALIAN PRIMARY BILIARY CIRRHOSIS: A MULTICENTER STUDY OF 664 PATIENTS AND 1992 HEALTHY CONTROLS
2008
Genetic factors are critical in determining susceptibility to primary biliary cirrhosis (PBC), but there has not been a clear association with human leukocyte antigen (HLA) genes. We performed a multicenter case-control study and analyzed HLA class II DRB1 associations using a large cohort of 664 well-defined cases of PBC and 1992 controls of Italian ancestry. Importantly, healthy controls were rigorously matched not only by age and sex, but also for the geographical origin of the proband four grandparents (Northern, Central, and Southern Italy). After correction for multiple testing, DRB1*08 [odds ratio (OR), 3.3; 95% confidence interval (CI), 2.4-4.5] and DRB1*02 (OR 0.9; 95% CI 0.8-1.2) …
Linkage analysis and disease models in benign familial infantile seizures: a study of 16 families.
2006
Summary: Purpose: Benign familial infantile seizures (BFIS) is a genetically heterogeneous condition characterized by partial seizures, onset age from 3 to 9 months, and favorable outcome. BFIS loci were identified on chromosomes 19q12-13.1 and 16p12-q12, allelic to infantile convulsions and choreathetosis. The identification of SCN2A mutations in families with only infantile seizures indicated that BFNIS and BFIS may show overlapping clinical features. Infantile seizures also were in a family with familial hemiplegic migraine and mutations in the ATP1A2 gene. We have examined the heterogeneous genetics of BFIS by means of linkage analysis. Methods: Sixteen families were examined. Probands …
Exploring a new incubation model for FinTechs: Regulatory sandboxes
2021
Research on incubation models indicates that incubators and accelerators are crucial catalysts for the development of start-ups. To facilitate start-ups in financial markets, several regulatory authorities have adopted a new incubation model called a ‘regulatory sandbox’. Regulatory sandboxes enable eligible applicants to test their technology-enabled financial solutions for a certain period of time (subject to conditions the regulator imposes). As such, these instruments allow innovation while preventing severe instability in financial markets caused by systemic risk. Despite their importance, management research has devoted little attention to studying how sandboxes operate as a new incub…
Cellular Models and Assays to Study NLRP3 Inflammasome Biology
2020
The NLRP3 inflammasome is a multi-protein complex that initiates innate immunity responses when exposed to a wide range of stimuli, including pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). Inflammasome activation leads to the release of the pro-inflammatory cytokines interleukin (IL)-1β and IL-18 and to pyroptotic cell death. Over-activation of NLRP3 inflammasome has been associated with several chronic inflammatory diseases. A deep knowledge of NLRP3 inflammasome biology is required to better exploit its potential as therapeutic target and for the development of new selective drugs. To this purpose, in the past few years, several tools have…
Ischemic Preconditioning: Postischemic Structural Changes in the Brain
2008
Ischemic brain damage can be prevented or at least significantly reduced when there is a preceding brief ischemic period that does not exceed the threshold for tissue damage--a phenomenon termed "ischemic preconditioning" (ischemic PC). Experimental PC in rodents is now considered to be a model for transient ischemic attacks in humans, and there is increasing hope for translating the knowledge of underlying mechanisms in the animal models into the clinic to enhance endogenous neuroprotective mechanisms in patients with stroke. However, although PC was originally defined as a subtoxic stimulus without any morphologic damage, there is a growing body of evidence from studies using sensitive te…
Involvement of Microglia in Neurodegenerative Diseases: Beneficial Effects of Docosahexahenoic Acid (DHA) Supplied by Food or Combined with Nanoparti…
2021
Neurodegenerative diseases represent a major public health issue and require better therapeutic management. The treatments developed mainly target neuronal activity. However, an inflammatory component must be considered, and microglia may constitute an important therapeutic target. Given the difficulty in developing molecules that can cross the blood–brain barrier, the use of food-derived molecules may be an interesting therapeutic avenue. Docosahexaenoic acid (DHA), an omega-3 polyunsaturated fatty acid (22:6 omega-3), has an inhibitory action on cell death and oxidative stress induced in the microglia. It also acts on the inflammatory activity of microglia. These data obtained in vitro or…
Differential Roles of JNK in ConA/GalN and ConA-Induced Liver Injury in Mice
2008
Tumor necrosis factor-alpha-mediated liver injury can be induced by several different means; however, the signaling events and mechanisms of cell death are likely different. We investigated the mechanism of both apoptotic and necrotic hepatocyte cell death as well as the role of c-Jun NH2-terminal kinase (JNK) in the ConA and ConA/D-galactosamine (GalN) models of murine liver injury. ConA alone induced primarily necrotic cell death with no caspase activation, whereas ConA/GalN induced apoptosis in addition to necrotic cell death. The bi-modal death pattern in the ConA/GalN model was confirmed by the use of transgenic mice expressing a dominant-negative form of Fas-associated death domain in…