Analysis of the predictive ability of time delay neural networksapplied to the S&P 500 time series

Reported work on financial time series prediction using neural networks often shows a characteristic one step shift relative to the original data. This seems to imply a failure of the neural network (NN), because a shift corresponds to a random walk prediction. Our systematic analysis of different time delay neural networks predictors applied to the detrended S&P 500 time series, indicates that this prediction behavior is not a limitation of the network, but may be a characteristic of the time series. This suggests that there are no short-term correlations in this stockmarket time series, which is consistent with conventional statistical analysis     

Field evaluation of agronomic effectiveness of multi-nutrient fertilizer briquettes for upland crop production

Low nutrient recovery in upland crop production systems has prompted studies to improve the current nutrient management practices to increase fertilizer efficiency. Field studies were conducted in two growing seasons (2012 and 2013) under two land management systems (till and no-till) to evaluate agronomic effectiveness of a multi-nutrient fertilizer briquette (fertilizer briquettes) for upland crop production, using corn as test crop. The fertilizer briquettes were produced through a simple physical compaction of ordinary granular fertilizers with a final nutrient composition of 23.9% N, 19.2% P₂O₅, 19.1% K₂O, 0.9% Zn, and 2.5% S. The agronomic efficiency of the fertilizer briquettes were compared with commercial N sources, urea and ammonium sulfate supplied separately with phosphorus (P), potassium (K), zinc (Zn), and sulfur (S; for urea alone). During the wetter (2013) weather conditions, the fertilizer briquette treatment consistently produced the highest yields in both locations. At Ames Plantation, the fertilizer briquette treatment increased grain yields by ~ 16 and ~ 23% over the treatments having ammonium sulfate and urea granular fertilizers, respectively, and, in Jackson, by 16 and 34% respectively. Nutrient recovery efficiency was also greatest with the fertilizer briquettes treatment. However, during the drier weather conditions (2012), the fertilizer briquettes treatment was the least effective among the three treatments in terms of biomass and grain yields, and nutrient recovery efficiency. We conclude, with adequate rainfall conditions, the fertilizer briquettes could be an efficient fertilizer for upland crop production. However, under drier weather conditions where soil moisture is limited, the fertilizer briquettes may not be an ideal fertilizer source for upland crop production.     

Decrease in serum total cholesterol and increase in high‐density lipoprotein cholesterol in rats following moderate intake of sherry

Moderate intake of sherry by rats resulted in a decrease in serum total cholesterol and an increase in the proportion of high‐density lipoprotein cholesterol. Oloroso, manzanilla, fino and amontillado sherries all exerted similar effects. These effects were apparently not related to the ethanol content, since an aqueous solution of ethanol did not modify cholesterol levels. Therefore other compounds must be responsible for the effects observed. This paper shows that, in addition to typical red and white wines, sherries should be included in the list of wines with beneficial physiological effects following moderate consumption. Copyright © 2004 Society of Chemical Industry     

Correlational relationship between shock intensity and corticosterone secretion on the establishment and subsequent expression of contextual fear conditioning.

A role for corticosterone in the consolidation of contextual fear conditioning has previously been proposed. In this study, physiological evidence was found to support this view. The extent of conditioned fear and the levels of plasma corticosterone in rats, after context exposure at training and at different posttraining times (24 hr and 7 days), depended on the intensity of the unconditional stimulus (footshock). In each experimental session, a positive correlation was found between the magnitude of corticosterone levels and the fear-related behavioral inhibition exhibited in the context. Results support the involvement of corticosterone on the processes that occur during consolidation in determining the strength at which the contextual fear conditioning is stored as a long-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Simulation,Power Quality Analysis and Improvements in a Hot Rolling Mill Using a STATCOM

This paper presents an analysis of the electric power flows in a hot rolling mill plant using a power quality analyzer and developing simulation models with Matlab-Simulink. The model inputs have been taken from process data by the process computer of the plant. Data from different rolling campaigns have been analysed. A STATCOM （static synchronous compensator） with a control strategy based on voltage oriented control with d-q coordinates is used as solution to improve the reactive compensation as well as to minimize the voltage fluctuations and sags effect. The overall electric model has been simulated with the STATCOM to check the improvement in the voltage stability and the consumption.     

Highly Regio- and Stereoselective Diels-Alder Cycloadditions via Two-Step and Multicomponent Reactions Promoted by Infrared Irradiation under Solvent-Free Conditions

Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1-3 with the Knoevenagel adducts 4-6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13-17), under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13-16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO) calculations.     

Many pathways in laboratory evolution can lead to improved enzymes: how to escape from local minima

Directed evolution is a method to tune the properties of enzymes for use in organic chemistry and biotechnology, to study enzyme mechanisms, and to shed light on darwinian evolution in nature. In order to enhance its efficacy, iterative saturation mutagenesis (ISM) was implemented. This involves: 1) randomized mutation of appropriate sites of one or more residues; 2) screening of the initial mutant libraries for properties such as enzymatic rate, stereoselectivity, or thermal robustness; 3) use of the best hit in a given library as a template for saturation mutagenesis at the other sites; and 4) continuation of the process until the desired degree of enzyme improvement has been reached. Despite the success of a number of ISM-based studies, the question of the optimal choice of the many different possible pathways remains unanswered. Here we considered a complete 4-site ISM scheme. All 24 pathways were systematically explored, with the epoxide hydrolase from Aspergillus niger as the catalyst in the stereoselective hydrolytic kinetic resolution of a chiral epoxide. All 24 pathways were found to provide improved mutants with notably enhanced stereoselectivity. When a library failed to contain any hits, non-improved or even inferior mutants were used as templates in the continuation of the evolutionary pathway, thereby escaping from the local minimum. These observations have ramifications for directed evolution in general and for evolutionary biological studies in which protein engineering techniques are applied.     

Dietary fatty acid intervention of lactating cows simultaneously affects lipid profiles of meat and milk

BACKGROUND: The present study investigated tissue‐specific responses of muscle and mammary gland to a 10 week intervention of German Holstein cows (n = 18) with three different dietary fat supplements (saturated fat; linseed oil or sunflower oil plus docosahexaenoic acid‐rich algae) by analysing fatty acid profiles and quality parameters of meat and milk. RESULTS: Plant oil/algae intervention affected neither fat content nor quality parameters of meat but decreased fat content and saturated fatty acid amounts of milk. Linseed oil/algae intervention caused significantly higher concentrations of C18:3n‐3 (meat, 1.0 g per 100 g; milk, 1.2 g per 100 g) and C22:6n‐3 (meat, 0.3 g per 100 g; milk, 0.14 g per 100 g). Sunflower oil/algae intervention increased n‐6 fatty acid contents in milk (4.0 g per 100 g) but not in meat. Elevated amounts of C18:1trans isomers and C18:1trans‐11 were found in meat and especially in milk of plant oil/algae‐fed cows. C18:1cis‐9 amounts were found to be increased in milk but decreased in meat after plant oil/algae intervention. CONCLUSION: The present study demonstrated that dietary fatty acid manipulation substantially shifted the fatty acid profiles of milk and to a lesser extent of meat, whereas meat quality traits were not affected. Indications of tissue‐specific responses of mammary gland and muscle were identified. Copyright © 2012 Society of Chemical Industry     

Cytotoxicity and Genotoxicity of Ceria Nanoparticles on Different Cell Lines in Vitro

Owing to their radical scavenging and UV-filtering properties, ceria nanoparticles (CeO₂-NPs) are currently used for various applications, including as catalysts in diesel particulate filters. Because of their ability to filter UV light, CeO₂-NPs have garnered significant interest in the medical field and, consequently, are poised for use in various applications. The aim of this work was to investigate the effects of short-term (24 h) and long-term (10 days) CeO₂-NP exposure to A549, CaCo2 and HepG2 cell lines. Cytotoxicity assays tested CeO₂-NPs over a concentration range of 0.5 μg/mL to 5000 μg/mL, whereas genotoxicity assays tested CeO₂-NPs over a concentration range of 0.5 μg/mL to 5000 μg/mL. In vitro assays showed almost no short-term exposure toxicity on any of the tested cell lines. Conversely, long-term CeO₂-NP exposure proved toxic for all tested cell lines. NP genotoxicity was detectable even at 24-h exposure. HepG2 was the most sensitive cell line overall; however, the A549 line was most sensitive to the lowest concentration tested. Moreover, the results confirmed the ceria nanoparticles’ capacity to protect cells when they are exposed to well-known oxidants such as H₂O₂. A Comet assay was performed in the presence of both H₂O₂ and CeO₂-NPs. When hydrogen peroxide was maintained at 25 μM, NPs at 0.5 μg/mL, 50 μg/mL, and 500 μg/mL protected the cells from oxidative damage. Thus, the NPs prevented H₂O₂-induced genotoxic damage.