951 research outputs found
Sudden death due to association between NAFLD and cardiovascular changes in a 37-year-Old Man: A case report
Fatty liver disease (FLD) is the most prevalent form of liver disease worldwide. Overnutrition can induce nonalcoholic fatty liver disease (NAFLD), a spectrum of conditions ranging from simple steatosis or nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis and cirrhosis. Some of the epidemiological and pathological studies have also suggested an association between the presence of fatty liver and sudden death. A 37-year-old man was found dead when he was asleep in the bed at home. According to his family, he was single and a costermonger. He was not an athlete, and there was no history of any physical and mental disorder. He was not addicted and did not use any drugs or alcohol. The positive points, in this case, were: a large heart with mild coronary stenosis and steatohepatitis in autopsy and sudden death. Since steatohepatitis did not have any complication such as fat embolism, it can be concluded that the combination of steatohepatitis and cardiovascular disorder led to sudden unexpected death. Heart more than 450 gr is susceptible to arrhythmia, and fatty liver disease can cause cardiovascular changes. © 2016 Tehran University of Medical Sciences. All rights reserved
Impact of Strain on the Performance of Si Nanowires Transistors at the Scaling Limit: A 3D Monte Carlo/2D Poisson Schrodinger Simulation Study
In this work we investigate the correlation between channel strain and device performance in various n-type Si-NWTs. We establish a correlation between strain, gate length and cross-section dimension of the transistors. For the purpose of this paper we simulate Si NWTs with a <110> channel orientation, four different ellipsoidal channel cross-sections and five gate lengths: 4nm, 6nm, 8nm, 10nm and 12nm. We have also analyzed the impact of strain on drain-induced barrier lowering (DIBL) and the subthreshold slope (SS). All simulations are based on a quantum mechanical description of the mobile charge distribution in the channel obtained from a 2D solution of the Schrödinger equation in multiple cross sections along the current path, which is mandatory for nanowires with such ultra-scale dimensions. The current transport along the channel is simulated using 3D Monte Carlo (MC) and drift-diffusion (DD) approaches
Observation of extensive bed of giant mangrove whelk in Minicoy, Lakshadweep
Terebralia palustris (Linnaeus, 1767) is a species
of Caenogastropod belonging to the family
Potamididae, distributed widely in Indo-Pacific
region and African coast. An extensive bed of T.
palustris approximately 500 m long and 70 m wide,
appearing like a canal stretching into the beach was
observed along the south west coast of Minicoy
Island, Lakshadweep
Type 2 myocardial infarction: a diagnostic and therapeutic challenge in contemporary cardiology
In the expanding world of cardiovascular diseases, rapidly reaching pandemic proportions, the main focus is still on coronary atherosclerosis and its clinical consequences. However, at least in the Western world, middle-aged male patients with acute myocardial infarction are no more the rule. Due to a higher life expectancy and major medical advances, physicians are to treat older and frailer individuals, usually with multiple comorbidities. In this context, myocardial ischaemia and infarction frequently result from an imbalance between myocardial oxygen supply and demand\u2014i.e., type 2 myocardial infarction (T2MI), according to the current universal definition\u2014rather than coronary atherothrombosis. Moreover, the increasing use of high-sensitivity cardiac troponin assays has led to a heightened detection of T2MI\u2014often causing relatively little myocardial injury\u2014, which seems to have doubled its numbers in recent years. Nevertheless, owing to its multifaceted pathophysiology and clinical presentation, T2MI is still underdiagnosed. Perhaps more importantly, T2MI is also victim of undertreatment, as drugs that constitute the cornerstone of therapy in most cardiovascular diseases are much more unlikely to be prescribed in T2MI than in coronary atherothrombosis. In this paper, we review the recent literature on the classification, pathophysiology, epidemiology, and management of T2MI, trying to summarise the state-of-the-art knowledge about this increasingly important pathologic condition. Finally, based on the current scientific evidence, we also propose an algorithm that may be easily utilised in clinical practice, in order to improve T2MI diagnosis and risk stratification
Impact of quantum confinement on transport and the electrostatic driven performance of silicon nanowire transistors at the scaling limit
In this work we investigate the impact of quantum mechanical effects on the device performance of n-type silicon nanowire transistors (NWT) for possible future CMOS applications at the scaling limit. For the purpose of this paper, we created Si NWTs with two channel crystallographic orientations <110> and <100> and six different cross-section profiles. In the first part, we study the impact of quantum corrections on the gate capacitance and mobile charge in the channel. The mobile charge to gate capacitance ratio, which is an indicator of the intrinsic performance of the NWTs, is also investigated. The influence of the rotating of the NWTs cross-sectional geometry by 90o on charge distribution in the channel is also studied. We compare the correlation between the charge profile in the channel and cross-sectional dimension for circular transistor with four different cross-sections diameters: 5nm, 6nm, 7nm and 8nm. In the second part of this paper, we expand the computational study by including different gate lengths for some of the Si NWTs. As a result, we establish a correlation between the mobile charge distribution in the channel and the gate capacitance, drain-induced barrier lowering (DIBL) and the subthreshold slope (SS). All calculations are based on a quantum mechanical description of the mobile charge distribution in the channel. This description is based on the solution of the Schrödinger equation in NWT cross sections along the current path, which is mandatory for nanowires with such ultra-scale dimensions
Design of a Base-Board for arrays of closely-packed Multi-Anode Photo-Multipliers
We describe the design of a Base-Board to house Multi-Anode Photo-Multipliers
for use in large-area arrays of light sensors. The goals, the design, the
results of tests on the prototypes and future developments are presented.Comment: 16 pages, 5 figures, submitted to Nucl. Instrum. and Meth.
Prognostic impact of neurohormonal inhibition in pulmonary arterial hypertension
Abstract
Background
Experimental evidence points towards a hyperactivity of the sympathetic nervous system and renin-angiotensin-aldosterone system in the pathobiology of pulmonary arterial hypertension (PAH), raising the hypothesis that blockade of neurohormonal axis may have favorable effects in this context.
Purpose
To assess the use and prognostic impact of neurohormonal inhibitors (NEUi) in a single centre cohort of subjects with PAH.
Methods
We analysed retrospectively collected data from our register of right heart catheterizations (RHC) performed consecutively from January 1st 2005 until October 31st 2018. We selected patients with PAH and complete information about demographics, biochemical data and drug therapy at the time of RHC. Patients on beta-blocker, angiotensin-converting enzyme inhibitor (ACEi), angiotensin receptor blocker (ARB) or mineralocorticoid receptor antagonist (MRA) at the time of RHC were classified as NEUi users. Comparisons between NEUi recipients and non-recipients were drawn by chi-square or t-test, as appropriate. Death from any cause was assessed by Kaplan-Meier analysis.
Results
Complete data were available for 57 PAH patients. Mean pulmonary artery pressure, pulmonary artery wedge pressure, diastolic pressure gradient, pulmonary vascular resistance and cardiac index were 45.0±14.9 mmHg, 10.9±3.5 mmHg, 16.0±10.2 mmHg, 8.8±5.1 Wood units and 2.5±0.8 l/min/m2 respectively. Twenty-seven subjects (47.4%) were taking at least one NEUi when RHC was performed: 12 (21.1%) were on beta-blocker, 15 (26.3%) on ACEi/ARB and 6 (10.5%) on MRA. NEUi users were significantly older (67.6±11.9 vs. 58.3±15.2 years, p=0.039), had a higher body mass index (25.9±4.4 vs. 23.6±3.5, p=0.029), more frequently systemic arterial hypertension (74.1% vs. 40.0%, p=0.020), smoking habit (51.9% vs. 20.0%, p=0.025) and lower estimated glomerular filtration rate (58.7±22.7 vs. 73.7±24.7 ml/min/1.73 m2, p=0.022) than non-users. Moreover, 5 NEUi users (18.5%), but no NEUi non-users, had a history of coronary artery disease. Hemodynamic parameters were similar in NEUi recipients and non-recipients (p=NS). Seven patients (25.9%) died in the NEUi users group vs. 17 (56.7%) in the non-users one (p=0.038). Kaplan-Meier analysis confirmed that subjects not taking NEUi were more likely to die over the course of follow-up (Log-Rank p=0.020) (Figure 1).
Conclusions
Our data identify a subset of atypical PAH patients, with pre-capillary pulmonary hypertension and a comorbidity profile for left heart disease (LHD), in whom NEUi have shown to improve survival. A prognostic benefit of NEUi, due to their effects on cardiovascular comorbidities in this kind of patients, has been speculated. Future prospective studies are needed to identify the most appropriate treatment strategies for atypical forms of PAH, with subtle and probably covert LHD.
Figure 1. Kaplan-Meier survival curves
Funding Acknowledgement
Type of funding source: Non
Pan-European ground-motion prediction equations for the average horizontal component of PGA, PGV, and 5 %-damped PSA at spectral periods up to 3.0 s using the RESORCE dataset
This article presents a set of Ground-Motion Prediction Equations (GMPEs) for Europe and the Middle East, derived from the RESORCE strong motion data bank, following a standard regression approach. The parametric GMPEs are derived for the peak ground acceleration, peak ground velocity, and 5 %-damped pseudo-absolute acceleration response spectra computed over 23 periods between 0.02 and 3 s, considering the average horizontal-component ground-motions. The GMPEs are valid for distances less than 300 km, hypocentral depth up to 35 km and over the magnitude range 4–7.6. Two metrics for the source-to-station distance (i.e. Joyner-Boore and hypocentral) are considered. The selected dataset is composed by 2,126 recordings (at a period of 0.1 s) related to 365 earthquakes, that includes strong-motion data from 697 stations.The EC8 soil classification (four classes from A to D) discriminates recording sites and four classes (normal, reverse, strike-slip, and unspecified) describe the style of faulting. A subset which contains only stations with measured Vs30 and earthquakes with specified focal mechanism (1,224 records from 345 stations and 255 earthquakes) is used to test of the accuracy of the median prediction and the variability associated to the broader data set. A random effect regression scheme is applied and bootstrap analyses are performed to estimate the 95 % confidence levels for the parameters. The total standard deviation sigma is decomposed into between-events and within-event components, and the site-to-site component is evaluated as well. The results show that the largest contribution to the total sigma is coming from the within-event component. When analyzing the residual distributions, no significant trends are observed that can be ascribed to the earthquake type (mainshock-aftershock classification) or to the non-linear site effects. The proposed GMPEs have lower median values than global models at short periods and large distances, while are consistent with global models at long periods (T>1) s. Consistency is found with two regional models developed for Turkey and Italy, as the considered dataset is dominated by waveforms recorded in these regions
Distinguishing ventricular septal bulge versus hypertrophic cardiomyopathy in the elderly
The burgeoning evidence of patients diagnosed with sigmoidal hypertrophic cardiomyopathy (HCM) later in life has revived the quest for distinctive features that may help discriminate it from more benign forms of isolated septal hypertrophy often labelled ventricular septal bulge (VSB). HCM is diagnosed less frequently than VSB at older ages, with a reversed female predominance. Most patients diagnosed with HCM at older ages suffer from hypertension, similar to those with VSB. A positive family history of HCM and/or sudden cardiac death and the presence of exertional symptoms usually support HCM, though they are less likely in older patients with HCM, and poorly investigated in individuals with VSB. A more severe hypertrophy and the presence of left ventricular outflow obstruction are considered diagnostic of HCM, though stress echocardiography has not been consistently used in VSB. Mitral annulus calcification is very prevalent in both conditions, whereas a restrictive filling pattern is found in a minority of older patients with HCM. Genetic testing has low applicability in this differential diagnosis at the current time, given that a causative mutation is found in less than 10% of elderly patients with suspected HCM. Emerging imaging modalities that allow non-invasive detection of myocardial fibrosis and disarray may help, but have not been fully investigated. Nonetheless, there remains a considerable morphological overlap between the two conditions. Comprehensive studies, particularly imaging based, are warranted to offer a more evidence-based approach to elderly patients with focal septal thickening
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