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Molecular modeling techniques are used to investigate the interaction of L-lysine in aqueous medium with silanol and methyl sites onto quartz substrates. The structure of water shells around L-lysine molecules is strongly affected by the relative hydrophilic/hydrophobic character of the surfaces, where the order is almost completely lost for partially hydrophilic surfaces, while well-defined hydration shells around L-lysine are obtained for hydrophobic surfaces.

Summary: Over 30,000 adult cardiac operations are carried out in the UK annually. A small number of these patients need to return to theatre in the first few days after the initial surgery, but the exact proportion is unknown. The majority of these resternotomies are for bleeding or cardiac tamponade. The Association of Cardiothoracic Anaesthesia and Critical Care carried out a 1‐year national audit of resternotomy in 2018. Twenty‐three of the 35 centres that were eligible participated. The overall resternotomy rate (95%CI) within the period of admission for the initial operation in these centres was 3.6% (3.37–3.85). The rate varied between centres from 0.69% to 7.6%. Of the 849 patients who required resternotomy, 127 subsequently died, giving a mortality rate (95%CI) of 15.0% (12.7–17.5). In patients who underwent resternotomy, the median (IQR [range]) length of stay on ICU was 5 (2–10 [0–335]) days, and time to tracheal extubation was 20 (12–48 [0–2880]) hours. A total of 89.3% of patients who underwent resternotomy were transfused red cells, with a median (IQR [range]) of 4 (2–7 [1–1144]) units of red blood cells. The rate (95%CI) of needing renal replacement therapy was 23.4% (20.6–26.5). This UK‐wide audit has demonstrated that resternotomy after cardiac surgery is associated with prolonged intensive care stay, high rates of blood transfusion, renal replacement therapy and very high mortality. Further research into this area is required to try to improve patient care and outcomes in patients who require resternotomy in the first 24 h after cardiac surgery. [ABSTRACT FROM AUTHOR]

In this paper, a novel three-dimensional autonomous chaotic system, the so-called Dadras-Momeni system, is considered and two different control techniques are employed to realize chaos control and chaos synchronization. First, the optimal control of the chaotic system is discussed and an open loop feedback controller is proposed to stabilize the system states to one of the system equilibria, minimizing the cost function by virtue of the Pontryagin's minimum principle. Then, an adaptive control law and an update rule for uncertain parameters, based on Lyapunov stability theory, are designed both to drive the system trajectories to an equilibrium or to realize a complete synchronization of the system in periodic and chaotic regimes. Numerical simulations are included to show the effectiveness of the designed controllers in realizing the stabilization and the synchronization of the chaotic system. Finally, a new hyperchaotic system is introduced by adding a controller to the second equation of the three-dimensional autonomous Dadras-Momeni chaotic system and the corresponding hyperchaotic attractor is shown via computer simulations. [ABSTRACT FROM AUTHOR]

In this paper, the valuation problem of a European call option in the presence of both stochastic volatility and transaction costs is considered. In the limit of small transaction costs and fast mean reversion, an asymptotic expression for the option price is obtained. While the dominant term in the expansion is shown to be the classical Black and Scholes solution, the correction terms appear at O(ε1/2) and O(ε). The optimal hedging strategy is then explicitly obtained for Scott's model. [ABSTRACT FROM AUTHOR]

Objective: On the basis of the known diabetes risk in polycystic ovary syndrome (PCOS), recent guidelines of the Endocrine Society recommend the use of an oral glucose tolerance test (OGTT) to screen for impaired glucose tolerance (IGT) and type 2 diabetes (T2DM) in all women with PCOS. However, given the high prevalence of PCOS, OGTT would have a high cost-benefit ratio. In this study, we identified, through a receiver operating characteristic analysis, simple predictive markers of the composite endpoint (impaired fasting glucose (IFG) or IGT or IFG + IGTor T2DM) in women with PCOS according to the Rotterdam criteria. Design: We conducted a cross-sectional study of 241 women with PCOS in a university hospital setting. Methods: Clinical, anthropometric, and metabolic (including OGTT) parameters were evaluated. The homeostasis model assessment of insulin resistance (HOMA2-IR), the Matsuda index of insulin sensitivity, and the oral dispositional index and visceral adiposity index (VAI) were determined. Results: Out of 241 women included in this study, 28 (11.6%) had an IFG, 13 (5.4%) had IGT, four (1.7%) had IFG + IGT, and four (1.7%) had T2DM. Among the anthropometric variables examined, the VAI had a significantly higher C-statistic compared with BMI (0.760(95% CI: 0.70-0.81) vs 0.613 (95% CI: 0.54-0.67); P=0.014) and waist circumference (0.760(95% CI: 0.70-0.81) vs 0.619 (95% CI: 0.55-0.68); P=0.028). Among all the hormonal and metabolic serum variables examined, DHEAS showed the highest C-statistic (0.720 (95% CI: 0.65-0.77); P<0.001). Conclusions: In addition to fasting glucose, the VAI and DHEAS may be considered useful tools for prescreening in all women with PCOS without the classical risk factors for diabetes. [ABSTRACT FROM AUTHOR]

Five viroid species have been reported from grapevine. Hop stunt viroid (HSVd) and Grapevine yellow speckle viroid 1 (GYSVd-1) are distributed worldwide, whereas Grapevine yellow speckle viroid 2 (GYSVd-2), Australian grapevine viroid (AGVd) and Citrus exocortis viroid (CEVd) are found only sporadically. However, the presence of AGVd and GYSVd-2 in several countries, including China, Turkey and Tunisia, suggests a wider dissemination, possibly also in Europe, where AGVd has never been found and GYSVd-2 has been occasionally identified in Italy. Taking advantage of a multiplex RT-PCR assay recently developed for detecting simultaneously these five viroids, vines growing in Italy in commercial vineyards and germplasm collections were surveyed. Besides confirming the widespread presence of HSVd and GYSVd-1 in the field, GYSVd-2 and/or AGVd were identified in two grapevine table cultivars (Sultanina Bianca and Red Globe) from germplasm collections. Tests extended to vines cultivated in southern Italy confirmed the presence of both viroids, which were further characterized. No major sequence divergences between the AGVd and GYSVd-2 variants from Italy and those previously described from other countries were observed. Phylogenetic analysis supported the close relationships among AGVd variants from Italy, Tunisia and Australia. To our knowledge this is the first report of AGVd in Europe and the first molecular characterization of GYSVd-2 isolates from a European country. [ABSTRACT FROM AUTHOR]

Stable isotope ratios (SIRs) of C, N, H and O have been exensively used in fruit juices quality control (ENV and AOAC methods) to detect added sugar and the watering down of concentrated juice, practices prohibited by European legislation (EU Directive 2012/12). The European Fruit Juice Association (AIJN) set some reference guidelines in order to allow the judging of the genuiness of a juice. Moreover, various studies have been carried out to determine the natural variability of SIRs in fruit juices, but none of these has investigated SIRs extensively in authentic citrus juices from Italy. In this work, about 500 citrus juice samples were officially collected in Italy by the Italian Ministry of Agricultural and Forestry Policies from 1998 onwards. (D/H)I and (D/H)II in ethanol and δ13Cethanol, δ13Cpulp, δ13Csugars, δ18Ovegetalwater, δ15Npulp, and δ18Opulp were determined using Site-Specific Natural Isotope Fractionation-Nuclear Magnetic Resonance and Isotope Ratio Mass Spectrometry, respectively. The characteristic ranges of variability in SIRs in genuine Italian citrus juice samples are here presented as well as their relationships and compliance with the limits indicated by the AIJN and others proposed in the literature. In particular, the Italian range of values was found to be not completely in agreement with AIJN guidelines, with the risk that genuine juices could be judged as not genuine. Variety seems not to influence SIRs, whereas harvest year and region of origin have some influence on the different ratios, although their data distribution shows overlapping when principal component analysis is applied. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this work we investigate the effect of density-dependent nonlinear diffusion on pattern formation in the Brusselator system. Through linear stability analysis of the basic solution we determine the Turing and the oscillatory instability boundaries. A comparison with the classical linear diffusion shows how nonlinear diffusion favors the occurrence of Turing pattern formation. We study the process of pattern formation both in onedimensional and two-dimensional spatial domains. Through a weakly nonlinear multiple scales analysis we derive the equations for the amplitude of the stationary patterns. The analysis of the amplitude equations shows the occurrence of a number of different phenomena, including stable supercritical and subcritical Turing patterns with multiple branches of stable solutions leading to hysteresis. Moreover, we consider traveling patterning waves: When the domain size is large, the pattern forms sequentially and traveling wave fronts are the precursors to patterning. We derive the Ginzburg-Landau equation and describe the traveling front enveloping a pattern which invades the domain. We show the emergence of radially symmetric target patterns, and, through a matching procedure, we construct the outer amplitude equation and the inner core solution. [ABSTRACT FROM AUTHOR]