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Autoignition delay times of NH3/CH4 mixtures with CH4 fractions of 0%, 5%, 10% and 50% were measured in a rapid compression machine at equivalence ratio φ = 0.5, pressures from 20 to 70 bar and temperatures from 930 to 1140 K. In addition, measurements were performed for NH3 mixtures with 10% CH4 at φ = 1.0 and 2.0. Methane shows a strong ignition-enhancing effect on NH3, which levels off at higher CH4 fractions, as the ignition delay time approaches that of pure methane. Autoignition delay times at 10% CH4 at φ = 0.5 and 1.0 are indistinguishable, while an increase of ignition delay times by factor of 1.5 was observed upon increasing φ to 2.0. The experimental data were used to evaluate six NH3 oxidation mechanisms capable of simulating NH3/CH4 mixtures. The mechanism previously used by the authors shows the best performance: generally, it predicts the measured ignition delay times to better than 30% for all conditions, except for 50% CH4 addition for which the differences increase up to 50% at the highest temperature. Sensitivity analysis based on the mechanism used indicates that under lean conditions the reaction CH4 + NH2 = CH3 + NH3 significantly promotes ignition for modest CH4 addition (5% and 10%), but becomes modestly ignition-inhibiting at 50% CH4. Sensitivity and rate-of-production analyses indicate that the ignition-enhancing effect of 50% CH4 addition is closely related to the formation and decomposition of H2O2. Flux analysis for NH3/CH4 mixtures indicates that CH4 + NH2 = CH3 + NH3 contributes substantially to the decomposition of methane early in the oxidation process, while CH3 + NO2 (+M) = CH3NO2 (+M) is a significant reservoir of NO2 at low temperature. Additionally, an anomalous pre-ignition pressure rise phenomenon, which is not reproduced by the simulations, was observed with high reproducibility for the NH3 mixture with 50% CH4 addition.

Galectin-3 plays a role in tissue inflammation, repair, and fibrosis. This article specifically focuses on heart failure (HF), in which galectin-3 has been shown to be a useful biomarker in prognosis and risk stratification, especially in HF with preserved ejection fraction. Experimental research has shown that galectin-3 directly induces pathologic remodeling of the heart, and is therefore considered a culprit protein in the development of cardiac fibrosis in HF, with potentially relevant clinical implications. In summary, galectin-3 is a biomarker and biotarget in cardiac remodeling and fibrosis and future research will target galectin-3-centered diseases.

There is growing interest in heat pumps based on materials that show thermal changes when phase transitions are driven by changes of electric, magnetic or stress field. Importantly, regeneration permits sinks and loads to be thermally separated by many times the changes of temperature that can arise in the materials themselves. However, performance and parameterization are compromised by net heat transfer between caloric working bodies and heat transfer fluids. Here we show that this net transfer can be avoided-resulting in true, balanced regeneration-if one varies the applied electric field while an electrocaloric (EC) working body dumps heat on traversing a passive fluid regenerator. Our EC working body is represented by bulk PbSc0.5Ta0.5O3 (PST) near its first-order ferroelectric phase transition, where we record directly measured adiabatic temperature changes of up to 2.2 K. Indirectly measured adiabatic temperature changes of similar magnitude were identified, unlike normal, from adiabatic measurements of polarization, at nearby starting temperatures, without assuming a constant heat capacity. The resulting high-resolution field-temperature-entropy maps of our material, and a small clamped companion sample, were used to construct cooling cycles that assume the use of an ideal passive regenerator in order to span $\leq$20 K. These cooling cycles possess well defined coefficients of performance that are bounded by well defined Carnot limits, resulting in large ($>$50%) well defined efficiencies that are not unduly compromised by a small field hysteresis. Our approach permits the limiting performance of any caloric material in a passive regenerator to be established, optimized and compared; provides a recipe for true regeneration in prototype cooling devices; and could be extended to balance active regeneration., 54 pages, 22 figures

The paper reviews recent research and development activities in the field of hydropower technology. It covers emerging and advanced technologies to mitigate flow instabilities (active and passive approach) as well as emerging magneto-rheological control techniques. Recent research findings on flow instabilities are also presented, especially concerning fluid-structure interaction and transient operating conditions. As a great number of the existing large-scale hydroelectric facilities were constructed decades ago using technologies that are now considered obsolete, technologies to achieve the digitalisation of hydropower are also analysed. Advances in the electro-mechanical components and generator design are presented; their potential role to adapt hydropower to the current operating conditions is also highlighted. The text explores current efforts to advance hydropower operation, mainly in terms of European projects. It provides a detailed overview of the recent efforts to increase the operational range of hydraulic turbines in order to reach exceptional levels of flexibility, a topic of several recent research projects. Variable speed hydropower generation and its application in pumped storage power plants are presented in detail. Moreover, revolutionary concepts for hydroelectric energy storage are also presented with the analysis focusing on underwater hydro storage and hydropower's hybridisation with fast energy storage systems. Efforts to minimise hydropower's environmental footprint are also presented via the utilisation of small-scale and fish-friendly installations.

The tanning industry uses large quantities of Cr whose contribution to the contaminant burden of aquatic organismsis not yet fully understood. The present study investigated Cr bioaccumulation by indigenous chironomids in a freshwater ecosystem impacted by tannery effluents. Total Cr content in sediments and in chironomidswas determined on several occasions. Chromium distribution among sediments and pore waters, and Cr speciation in overlying and pore waters were studied in detail to understand possible factors controlling Cr bioavailability to chironomids. Total chromium concentration ranged from 69 to over 3000 mu g g(-1) dry weight in sediments and fromnegligible to over 300 mu g g(-1) dryweight in chironomids (values corrected for sediment gut content). Filterable (

Far-field measurements of lightning-produced electromagnetic fields are of high importance for lightning location systems. Data from recorded lightning strokes can be, for example, used to assess the risk of lightning-induced damage in some geographical areas. Artificially triggered lightning, usually generated using rocket-wire technology, plays an important role in the study of lightning physics. Multiple-station observations of far (typically larger than 20 km) electric field waveforms produced by rocket- triggered lightning are quite rare. In 2014, electric field waveforms were measured for return strokes through the rocket-and-wire technique at Conghua. They were measured by electric field sensors at nine sites belonging to the lightning locating system in Foshan, Guangzhou, China. A total of 38 events were recorded and overall statistics of those waveforms are presented. The results were compared to previous experimental data related to natural and artificially triggered lightning to validate their similarity.

WOS: 000416498700046, In this study, the cyclic variability of a diesel engine using diesel fuel and butanol diesel fuel blends is modeled using an artificial neural network (ANN) method. The engine was operated with ten different engine speeds and full load conditions using six different n-butanol diesel fuel blends. The coefficient of variation (COV) of the indicated mean effective pressure (IMEP), which is a well-accepted evaluation method, was used to assess the cyclic variability for 100 sequential engine cycles. Results indicated that adding n-butanol to diesel fuel caused an increase. Moreover, the COVimep values exhibited a decreasing trend with an increase in the engine speed for each fuel. The experimental results were used to train the ANN. The ANN network was trained with Levenberg - Marquardt (LM) and Scaled Conjugate Gradient (SCG) algorithms. After training the ANN, it was found that the coefficient of determination (R-2) values were in the range of between 0.737 and 0.9677, the mean-absolute-percentage error (MAPE) values were smaller than 8.7 and the mean-square error values (MSE) were smaller than 0.042. The predictions of the developed ANN model showed reasonable consistency with the experimental results. (C) 2017 Elsevier Ltd. All rights reserved., Research Fund of Karadeniz Technical University [FYL-2015-5286], This work was supported by the Research Fund of Karadeniz Technical University, Project number: FYL-2015-5286.

This study investigated the role of maturity timing in selection procedures and in the specialisation of playing positions in youth male basketball. Forty-three talented Dutch players (14.66 ± 1.09 years) participated in this study. Maturity timing (age at peak height velocity), anthropometric, physiological, and technical characteristics were measured. Maturity timing and height of the basketball players were compared with a matched Dutch population. One-sample t-tests showed that basketball players were taller and experienced their peak height velocity at an earlier age compared to their peers, which indicates the relation between maturity timing and selection procedures. Multivariate analysis of variance (MANOVA) showed that guards experienced their peak height velocity at a later age compared to forwards and centres (P.01). In addition, positional differences were found for height, sitting height, leg length, body mass, lean body mass, sprint, lower body explosive strength, and dribble (P.05). Multivariate analysis of covariance (MANCOVA) (age and age at peak height velocity as covariate) showed only a significant difference regarding the technical characteristic dribbling (P.05). Coaches and trainers should be aware of the inter-individual differences between boys related to their maturity timing. Since technical characteristics appeared to be least influenced by maturity timing, it is recommended to focus more on technical characteristics rather than anthropometric and physiological characteristics.

Heart failure (HF) is a common disease and affects millions of patients worldwide. Diagnosis, risk assessment and treatment of HF are difficult and therefore there is a need for additional tools to improve clinical performance. Biomarkers may be helpful in this respect. Galectin-3 is a relatively new biomarker that has been shown to have strong associations with the development of HF. Galectin-3 plays a role in inflammation and fibrosis, which are key elements in the pathophysiology of HF. Circulating plasma or serum galectin-3 levels have strong associations with the severity of HF and may be used to prognosticate or risk-stratify HF patients. Currently, there are several commercially available assays that can measure circulating galectin-3. This article describes the role galectin-3 plays in HF and its prognostic consequences. We will summarize the technical specifications of various manual and automated galectin-3 assays, which may help in HF management.

Heart failure (HF) is a common disease and affects millions of patients worldwide. Diagnosis, risk assessment and treatment of HF are difficult and therefore there is a need for additional tools to improve clinical performance. Biomarkers may be helpful in this respect. Galectin-3 is a relatively new biomarker that has been shown to have strong associations with the development of HF. Galectin-3 plays a role in inflammation and fibrosis, which are key elements in the pathophysiology of HF. Circulating plasma or serum galectin-3 levels have strong associations with the severity of HF and may be used to prognosticate or risk-stratify HF patients. Currently, there are several commercially available assays that can measure circulating galectin-3. This article describes the role galectin-3 plays in HF and its prognostic consequences. We will summarize the technical specifications of various manual and automated galectin-3 assays, which may help in HF management.

Talent identification research in soccer comprises the prediction of elite soccer performance. While many studies in this field have aimed to empirically relate performance characteristics to subsequent soccer success, a critical evaluation of the methodology of these studies has mostly been absent in the literature. In this position paper, we discuss advantages and limitations of the design, validity, and utility of current soccer talent identification research. Specifically, we draw on principles from selection psychology that can contribute to best practices in the context of making selection decisions across domains. Based on an extensive search of the soccer literature, we identify four methodological issues from this framework that are relevant for talent identification research, i.e. (1) the operationalization of criterion variables (the performance to be predicted) as performance levels; (2) the focus on isolated performance indicators as predictors of soccer performance; (3) the effects of range restriction on the predictive validity of predictors used in talent identification; and (4) the effect of the base rate on the utility of talent identification procedures. Based on these four issues, we highlight opportunities and challenges for future soccer talent identification studies that may contribute to developing evidence-based selection procedures. We suggest for future research to consider the use of individual soccer criterion measures, to adopt representative, high-fidelity predictors of soccer performance, and to take restriction of range and the base rate into account.

The purpose of this study was to investigate the relationship between the development of the technical skill dribbling during ages 14-18 and adulthood playing level. The results gained insight in the required level of the technical skill dribbling during adolescence to be capable of becoming a professional soccer player. Talented players (n=131), aged 14-18 were measured while they were part of a developmental soccer program, testing took place annually. The players were identified as professional (n=54) or amateur (n=77) later on in their career (age > 20). In total 238 measurements of dribbling performance were assessed by means of the Shuttle Dribble Test. A longitudinal model estimated the development for optimal dribbling performance (peak dribbling) and for dribbling performance under fatigue (repeated dribbling), for players ultimately reaching professional status and for players reaching amateur status. The longitudinal results showed that during adolescence the talented players who ultimately became professionals were on average 0.3 s faster on 30m peak dribbling performance and on average I second faster on 3x30m repeated dribbling performance than the players who ultimately turned amateur (p=0.001). It is concluded that during adolescence dribbling performance can assist in identifying the best players for the future.

In a previous [F-18]fluorodeoxyglucose (FDG) PET study we analyzed regional metabolic data from a combined group of Parkinson's disease (PD) patients and healthy volunteers (N), using network analysis. By this method, we identified a unique pattern of regional metabolic covariation with an expression which accurately discriminated patients from healthy volunteers. To assess the reproducibility of this pattern as a potential marker for PD, we compared the pattern's topography with that of the disease-related covariance patterns identified in three other independent populations of patients with PD and healthy individuals studied in different PET laboratories. Methods: The following patient populations were studied: group A (original cohort: 22 PD, 20 N; resolution: 7.5 mm full width at half maximum [FWHM]); group B (18 PD, 12 N; resolution: 4.2 mm FWHM); group C (25 PD, 15 N; resolution: 8.0 mm FWHM); and group D (14 PD, 10 N; resolution: 10 mm FWHM). Region weights for the PD-related covariance pattern (PDRP) identified in the group A analysis were correlated with those for the disease-related patterns identified in the analyses of groups B, C and D, In addition, subject scores for the group A PDRP were computed prospectively for every individual in each of the study populations. PDRP scores for PD and N within each cohort were compared. Results: The PDRP topography identified in group A was highly correlated with each of the corresponding topographies identified in the other populations (r(2) similar to 0.60, P

OBJECTIVE: To determine (i) whether early viral kinetics or other markers during a modified treatment regimen are predictors of treatment outcome and (ii) whether fast responders can be treated for 24 weeks, without compromising the sustained virologic response (SVR) rate. MATERIAL AND METHODS: One hundred "difficult-to-treat" chronic hepatitis C patients (46 previous non-responders/relapsers (any genotype), 54 treatment-naive patients genotypes 1 and 4) were treated with triple antiviral induction therapy: amantadine hydrochloride and ribavirin, combined with 6 weeks interferon alfa-2b induction (weeks 1-2: 18 MU/day, weeks 3-4: 9 MU/day, weeks 5-6: 6 MU/day), thereafter combined with weekly peginterferon alfa-2b. Fast responders (>or=3 log(10) HCV RNA decline at week 4) were randomized to 24 or 48 weeks. Slow responders ( or= or or=5 IU/mL at week 16 became non-SVR. In previous non-responders/relapsers, the predictive value for SVR was 83% if HCV RNA was or=5 IU/mL at week 8 became non-SVR. CONCLUSIONS: With high-dose interferon induction, SVR and non-SVR can be predicted reliably within 16 weeks. Fast responders can be treated for 24 weeks, and SVR is independent of baseline viral load in fast responders

Cross-linked polyacrylamide gels have found wide application in analytical techniques, such as diffusional equilibration in thin film (DET) and diffusive gradient in thin film (DGT). In these applications, the assumption is made that the gel matrix is effectively uncharged and chemically inert with respect to the species of interest. Recent data has shown significant nonideal behavior at low ionic strengths, which strongly suggests a finite structural charge within the gel matrix. The present investigation explores the possible ramifications of fixed charged sites within the gel on metal speciation analysis by DET and DGT. The results indicate that structural charge within the gel layer will give rise to different DET equilibrium concentrations than in the sample because of Donnan partitioning. The steady-state diffusion of ions through a diffusive gel (DGT) is also influenced by the gel charge, but the net effect will depend on the details of the speciation. The results indicate that for submillimolar ionic strength solutions the quantitative interpretation of DGT data benefits from combination with DET.

ISBN: 078033504X; In this work, a novel and straightforward enable/disable GaAs MESFET Differential Logic (EMDL) structure is presented. EMDL is compatible with DCFL and some reported MESFET differential logic families, like DPTL, DCVS and DC/sup 2/FL. No power dissipation during the standby state, fewer transistors per logic function and noise immunity are its more interesting features. The EMDL can be efficiently applied in both synchronous and asynchronous designs. EMDL iterative network micropipeline applications are detailed. An 8-bit ripple carry adder was successfully fabricated and tested verifying the EMDL functionality and performance characteristics.

In a previous [F-18]fluorodeoxyglucose (FDG) PET study we analyzed regional metabolic data from a combined group of Parkinson's disease (PD) patients and healthy volunteers (N), using network analysis. By this method, we identified a unique pattern of regional metabolic covariation with an expression which accurately discriminated patients from healthy volunteers. To assess the reproducibility of this pattern as a potential marker for PD, we compared the pattern's topography with that of the disease-related covariance patterns identified in three other independent populations of patients with PD and healthy individuals studied in different PET laboratories. Methods: The following patient populations were studied: group A (original cohort: 22 PD, 20 N; resolution: 7.5 mm full width at half maximum [FWHM]); group B (18 PD, 12 N; resolution: 4.2 mm FWHM); group C (25 PD, 15 N; resolution: 8.0 mm FWHM); and group D (14 PD, 10 N; resolution: 10 mm FWHM). Region weights for the PD-related covariance pattern (PDRP) identified in the group A analysis were correlated with those for the disease-related patterns identified in the analyses of groups B, C and D, In addition, subject scores for the group A PDRP were computed prospectively for every individual in each of the study populations. PDRP scores for PD and N within each cohort were compared. Results: The PDRP topography identified in group A was highly correlated with each of the corresponding topographies identified in the other populations (r(2) similar to 0.60, P