The rapid technological developments of the past decade and the changes in echocardiographic practice brought about by these developments have resulted in the need for updated recommendations to the ...previously published guidelines for cardiac chamber quantification, which was the goal of the joint writing group assembled by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. This document provides updated normal values for all four cardiac chambers, including three-dimensional echocardiography and myocardial deformation, when possible, on the basis of considerably larger numbers of normal subjects, compiled from multiple databases. In addition, this document attempts to eliminate several minor discrepancies that existed between previously published guidelines.
A novel polyaniline-modified CNT and graphene-based nanocomposite (2.32–7.34 nm) was prepared and characterized by spectroscopic methods. The specific surface area was 176 m2/g with 0.232 cm3/g as ...the specific pore volume. The nanocomposite was used to remove zinc and lead metal ions from water; showing a high removal capacity of 346 and 581 mg/g at pH 6.5. The data followed pseudo-second-order, intraparticle diffusion and Elovich models. Besides this, the experimental values obeyed Langmuir and Temkin isotherms. The results confirmed that the removal of lead and zinc ions occurred in a mixed mode, that is, diffusion absorption and ion exchange between the heterogeneous surface of the sorbent containing active adsorption centers and the solution containing metal ions. The enthalpy values were 149.9 and 158.6 J.mol−1K−1 for zinc and lead metal ions. The negative values of free energies were in the range of −4.97 to −26.3 kJ/mol. These values indicated an endothermic spontaneous removal of metal ions from water. The reported method is useful to remove the zinc and lead metal ions in any water body due to the high removal capacity of nanocomposite at natural pH of 6.5. Moreover, a low dose of 0.005 g per 30 mL made this method economical. Furthermore, a low contact time of 15 min made this method applicable to the removal of the reported metal ions from water in a short time. Briefly, the reported method is highly economical, nature-friendly and fast and can be used to remove the reported metal ions from any water resource.
The rapid technological developments of the past decade and the changes in echocardiographic practice brought about by these developments have resulted in the need for updated recommendations to the ...previously published guidelines for cardiac chamber quantification, which was the goal of the joint writing group assembled by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. This document provides updated normal values for all four cardiac chambers, including three-dimensional echocardiography and myocardial deformation, when possible, on the basis of considerably larger numbers of normal subjects, compiled from multiple databases. In addition, this document attempts to eliminate several minor discrepancies that existed between previously published guidelines.
Background Studies have demonstrated that the current US guidelines based on American College of Cardiology/American Heart Association (ACC/AHA) Pooled Cohort Equations Risk Calculator may ...underestimate risk of atherosclerotic cardiovascular disease ( CVD ) in certain high-risk individuals, therefore missing opportunities for intensive therapy and preventing CVD events. Similarly, the guidelines may overestimate risk in low risk populations resulting in unnecessary statin therapy. We used Machine Learning ( ML ) to tackle this problem. Methods and Results We developed a ML Risk Calculator based on Support Vector Machines ( SVM s) using a 13-year follow up data set from MESA (the Multi-Ethnic Study of Atherosclerosis) of 6459 participants who were atherosclerotic CVD-free at baseline. We provided identical input to both risk calculators and compared their performance. We then used the FLEMENGHO study (the Flemish Study of Environment, Genes and Health Outcomes) to validate the model in an external cohort. ACC / AHA Risk Calculator, based on 7.5% 10-year risk threshold, recommended statin to 46.0%. Despite this high proportion, 23.8% of the 480 "Hard CVD " events occurred in those not recommended statin, resulting in sensitivity 0.76, specificity 0.56, and AUC 0.71. In contrast, ML Risk Calculator recommended only 11.4% to take statin, and only 14.4% of "Hard CVD " events occurred in those not recommended statin, resulting in sensitivity 0.86, specificity 0.95, and AUC 0.92. Similar results were found for prediction of "All CVD " events. Conclusions The ML Risk Calculator outperformed the ACC/AHA Risk Calculator by recommending less drug therapy, yet missing fewer events. Additional studies are underway to validate the ML model in other cohorts and to explore its ability in short-term CVD risk prediction.
This paper considers the synthesis of a novel nanocomposite based on reduced graphene oxide and oxidized carbon nanotubes modified with polyaniline and phenol-formaldehyde resin and developed through ...the carbonization of a pristine aerogel. It was tested as an efficient adsorbent to purify aquatic media from toxic Pb(II). Diagnostic assessment of the samples was carried out through X-ray diffractometry, Raman spectroscopy, thermogravimetry, scanning and transmission electron microscopy, and infrared spectroscopy. The carbonized aerogel was found to preserve the carbon framework structure. The sample porosity was estimated through nitrogen adsorption at 77 K. It was found that the carbonized aerogel predominantly represented a mesoporous material having a specific surface area of 315 m
/g. After carbonization, an increase in smaller micropores occurred. According to the electron images, the highly porous structure of the carbonized composite was preserved. The adsorption capacity of the carbonized material was studied for liquid-phase Pb(II) extraction in static mode. The experiment results showed that the maximum Pb(II) adsorption capacity of the carbonized aerogel was 185 mg/g (at pH 6.0). The results of the desorption studies showed a very low desorption rate (0.3%) at pH 6.5 and a rate of about 40% in a strongly acidic medium.
Summary Background Few studies have formally compared the predictive value of the blood pressure at night over and beyond the daytime value. We investigated the prognostic significance of the ...ambulatory blood pressure during night and day and of the night-to-day blood pressure ratio. Methods We did 24-h blood pressure monitoring in 7458 people (mean age 56·8 years SD 13·9) enrolled in prospective population studies in Denmark, Belgium, Japan, Sweden, Uruguay, and China. We calculated multivariate-adjusted hazard ratios for daytime and night-time blood pressure and the systolic night-to-day ratio, while adjusting for cohort and cardiovascular risk factors. Findings Median follow-up was 9·6 years (5th to 95th percentile 2·5–13·7). Adjusted for daytime blood pressure, night-time blood pressure predicted total (n=983; p<0·0001), cardiovascular (n=387; p<0·01), and non-cardiovascular (n=560; p<0·001) mortality. Conversely, adjusted for night-time blood pressure, daytime blood pressure predicted only non-cardiovascular mortality (p<0·05), with lower blood pressure levels being associated with increased risk. Both daytime and night-time blood pressure consistently predicted all cardiovascular events (n=943; p<0·05) and stroke (n=420; p<0·01). Adjusted for night-time blood pressure, daytime blood pressure lost prognostic significance only for cardiac events (n=525; p≥0·07). Adjusted for the 24-h blood pressure, night-to-day ratio predicted mortality, but not fatal combined with non-fatal events. Antihypertensive drug treatment removed the significant association between cardiovascular events and the daytime blood pressure. Participants with systolic night-to-day ratio value of 1 or more were older, at higher risk of death, and died at an older age than those whose night-to-day ratio was normal (≥0·80 to <0·90). Interpretation In contrast to commonly held views, daytime blood pressure adjusted for night-time blood pressure predicts fatal combined with non-fatal cardiovascular events, except in treated patients, in whom antihypertensive drugs might reduce blood pressure during the day, but not at night. The increased mortality in patients with higher night-time than daytime blood pressure probably indicates reverse causality. Our findings support recording the ambulatory blood pressure during the whole day.
Heart failure is a complex progressive clinical syndrome which is initiated by risk factors (e.g., hypertension, obesity, and diabetes), then proceeds to asymptomatic maladaptive left ventricular ...remodeling and dysfunction, and finally evolves into clinically overt, symptomatic heart failure, disability, and death. The progression of left ventricular dysfunction is associated with changes in cardiac energy metabolism. Mitochondria play a central role in a variety of cardiomyocytes functions, including oxidative energy production, storage of calcium ions, and programmed cell death. The mitochondrial DNA (mtDNA) content correlates with the size and number of mitochondria, which change under different energy demands and oxidative stress. Experimental studies demonstrated that any genetic manipulation resulting in significantly decreased mtDNA could accelerate the ageing process and cause adverse myocardial remodeling and dysfunction. On the other hand, preservation of the mtDNA copy number in mouse hearts delays the development of heart failure after myocardial infarction. Recent general population study also demonstrated that echocardiographic indexes of left ventricular structure and function are significantly and independently associated with mtDNA content measured at peripheral blood cells in cross-sectional and longitudinal analyses. In this chapter, we will discuss the recent experimental, clinical and epidemiological data of the possible impact of mtDNA content on cardiac structure and function.
In this work, dynamic mechanical contact behaviors and sintering mechanism of Al nanoparticles subjected to high-speed impact have been investigated using molecular dynamic simulations by analyzing ...radial distribution function (RDF), atomic average displacement, mean square displacement (MSD), the sintering neck radius, shrinkage, nanoparticle temperature and the proportion of amorphous atoms. The results shows that the long-ranged ordered structure of Al nanoparticles gradually transforms into short-range ordered structure and finally amorphous structure during the head-on impact. The atomic average displacement, MSD, radius ratio (x/R) and shrinkage at different initial impact speeds first experience a rapid increase to a maximum, followed by a slow decrease and subsequent a recovery to an almost constant. The displacement of surface atoms is always larger than the internal atoms during the head-on impact. There exists one critical impact velocity (e.g., 2800 m/s for given 4 nm in diameter) beyond which the ordered aluminum atoms completely transform into amorphous structure. The contact force, contact radius and contact stress obtained under a given low impact velocity and small strain are quite consistent with the predictions of the continuous Hertz model, but as the impact velocity and normal displacement further increase, the predictions of Hertz model underestimate these contact parameters. The influence of nanoparticle size on the relationship of contact radius and number of contacting atoms is inappreciable. The nanoparticles undergo elastic deformation, and then plastic deformation, followed by mechanical failure and shock-induced melting process into a whole. This work could strengthen our understanding of the industrial processes with applications in energetic nanomaterials, rocket propellant, metal sintering, etc.
•Contact behaviors and sintering mechanism of Al nanoparticles under impact have been studied by MD simulations.•The crystal structure of Al nanoparticles is continuously destroyed under high-speed impact.•Al nanoparticles with 4 nm in diameter will be melted when the initial impact velocity is greater than 2800 m/s.•Al nanoparticles have been undergone elastic and plastic deformation, mechanical failure and final melting.•The simulation results confirm that the Hertz model still hold only at low impact speed and at small strain.