bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and Structure of a Novel Biindole Pigment Substituted with an Ethyl Group from a Metagenomic Library Derived from the Marine Sponge Halichondria okadai
Authors: Abe Takahiro , Kukita Akira , Akiyama Kiyotaka , Naito Takayuki , Uemura Daisuke
Published: June 2012

We screened a colored clone from a metagenomic library derived from the marine sponge Halichondria okadai. We isolated a yellow pigment, halichrome A (1), which was structurally elucidated to be a biindole, exhibited cytotoxicity against B16 melanoma cells and was substituted with an ethyl group. To the best of our knowledge, this is the first report of the isolation of a novel compound from a metagenomic library derived from a marine sponge.
Repeatable Wettability Conversion between Hydrophobic and Superhydrophilic States on Nonwoven Fabrics Based on Electrospun TiO2–Poly(dimethylsiloxane) Fibers
Authors: Nakata Kazuya , Sakai Munetoshi , Liu Baoshun , Ochiai Tsuyoshi , Murakami Taketoshi , Fujishima Akira
Published: June 2012

Nonwoven fabrics based on composite fibers of TiO2 and poly(dimethylsiloxane) (PDMS) are prepared by electrospinning. Nonwoven fabrics based on TiO2–PDMS fibers are initially hydrophobic and undergo rapid wettability conversion to a superhydrophilic state upon plasma irradiation. Hydrophobicity is rapidly recovered under ambient conditions. This wettability conversion can be repeated by subsequent cycles of plasma irradiation and storage under ambient conditions.
Pt-Catalyzed Oxidative Rearrangement of Cyclic Tertiary Allylic Alcohols to Enones Using Aqueous Hydrogen Peroxide
Authors: Nagamine Takashi , Kon Yoshihiro , Sato Kazuhiko
Published: June 2012

An oxidative rearrangement of cyclic tertiary allylic alcohols to β-disubstituted α,β-unsaturated ketones by Pt black catalyst with aqueous hydrogen peroxide is described. The reaction proceeds under organic solvent- and halide-free conditions and gives only water as a coproduct. The Pt black catalyst is commercially available and can be reused at least four times.
Rrp6 is recruited to transcribed genes and accompanies the spliced mRNA to the nuclear pore
Authors: Hessle Viktoria , von Euler Anne , González de Valdivia Ernesto , Visa Neus
Published: June 2012

Rrp6 is an exoribonuclease involved in the quality control of mRNA biogenesis. We have analyzed the association of Rrp6 with the Balbiani ring pre-mRNPs of Chironomus tentans to obtain insight into the role of Rrp6 in splicing surveillance. Rrp6 is recruited to transcribed genes and its distribution along the genes does not correlate with the positions of exons and introns. In the nucleoplasm, Rrp6 is bound to both unspliced and spliced transcripts. Rrp6 is released from the mRNPs in the vicinity of the nuclear pore before nucleo-cytoplasmic translocation. We show that Rrp6 is associated with newly synthesized transcripts during all the nuclear steps of gene expression and is associated with the transcripts independently of their splicing status. These observations suggest that the quality control of pre-mRNA splicing is not based on the selective recruitment of the exoribonuclease Rrp6 to unprocessed mRNAs.
A Stochastic Target Approach for P&L Matching Problems
Authors: Bouchard Bruno , Nam Vu Thanh
Published: June 2012

Within a Brownian diffusion Markovian framework, we provide a direct PDE characterization of the minimal initial endowment required so that the terminal wealth of a financial agent (possibly diminished by the payoff of a random claim) can match a set of constraints in probability. Such constraints should be interpreted as a rough description of a targeted profit and loss (P&L) distribution. This allows us to give a price to options under a P&L constraint, or to provide a description of the discrete P&L profiles that can be achieved given an initial capital. This approach provides an alternative to the standard utility indifference (or marginal) pricing rules that is better adapted to market practices. From the mathematical point of view, this is an extension of the stochastic target problem under controlled loss, studied in Bouchard, Touzi, and Elie [Bouchard B, Touzi N, Elie R (2009) Stochastic target problems with controlled loss. SIAM J. Control Optim. 48(5):3123–3150], to the case of multiple constraints. Although the associated Hamilton-Jacobi-Bellman operator is fully discontinuous, and the terminal condition is irregular, we are able to construct a numerical scheme that converges at any continuity points of the pricing function.
Coalitions in Nonatomic Network Congestion Games
Authors: Wan Cheng
Published: June 2012

This work shows that the formation of a finite number of coalitions in a nonatomic network congestion game benefits everyone. At the equilibrium of the composite game played by coalitions and individuals, the average cost to each coalition and the individuals' common cost are all lower than in the corresponding nonatomic game (without coalitions). The individuals' cost is lower than the average cost to any coalition. Similarly, the average cost to a coalition is lower than that to any larger coalition. Whenever some members of a coalition become individuals, the individuals' payoff is increased. In the case of a unique coalition, both the average cost to the coalition and the individuals' cost are decreasing with respect to the size of the coalition. In a sequence of composite games, if a finite number of coalitions are fixed, and the size of the remaining coalitions goes to zero, the equilibria of these games converge to the equilibrium of a composite game played by the same fixed coalitions and the remaining individuals.
Estimation of Ultimate Lateral Load Capacity of Piles in Sands Using Calibration Chamber Tests
Authors: Lee Junhwan , Paik Kyuho , Kim Daehong , Park Donggyu
Published: June 2012

Current practice for the estimation of the ultimate lateral load capacity of piles is typically based on the vertical effective stress σ′v, while the effect of the lateral effective stress σ′h is not specifically considered. In the present study, calibration chamber lateral pile load tests are conducted to investigate the load response and ultimate lateral load capacity Hu of laterally loaded piles under various soil and stress conditions. In order to determine Hu from load-deflection curves, different criteria are explored and analyzed. From the test results, it is shown that Hu increases significantly with increasing σ′h for a given σ′v. It is also found that lateral deflection of pile at ultimate state tends to increase as the relative density and lateral stress increase. On the basis of the test results, the lateral stress correction factor reflecting the effect of the lateral effective stress σ′h on Hu is proposed. From the test results, it is seen that the proposed procedure using the lateral stress correction factor produces more realistic estimation of Hu. Case examples are selected from the literature and used to compare results measured and predicted using the proposed approach.
Effect of sorption process on cadmium transport
Authors: Mahdavi Ali , Kashefipour Seyed Mahmood , Omid Mohammad Hosein
Published: June 2012

The effect of sorption of cadmium to sediments is investigated through an experimental and numerical study. A numerical model is developed to evaluate the kinetic and equilibrium sorption process of heavy metal transport and transformation. The model was calibrated with results from experiments on cadmium and salt injection in a circular flume. The effect of sediment on sorption was then investigated by the aid of advection–dispersion experiments and numerical results. The results show that sorption reduces the dispersion coefficient but has no effect on advection rate. The results also indicate that the linearisation method of estimating sorption parameters is unsuitable. It was also found that a pseudo second-order model for kinetic sorption improves the results obtained in comparison with a first-order model. Comparison between the kinetic and equilibrium models showed that assuming equilibrium conditions underestimates transport velocity.
Effects of Polymer‐Coated Urea Application Ratios and Dates on Wheat and Subsequent Double‐Crop Soybean
Authors: Nash P. R. , Nelson K. A. , Motavalli P. P. , Meinhardt C. G.
Published: June 2012

Effective management of soil N fertilizer, including the use of enhanced efficiency N fertilizer sources and optimal dates of fertilizer application, may increase agronomic performance of double‐cropped winter wheat (Triticum aestivum L.) with soybean [Glycine max (L.) Merr.] under no‐till (NT) management. In a double‐cropping system, ratios and dates of application of polymer‐coated urea (PCU) may affect both wheat and subsequent soybean yields. The objectives of this research, conducted over three growing seasons (2008–2010) in northeastern Missouri, were to evaluate urea release over a range of PCU application dates, and to assess the effects of the fall to spring application dates of PCU and ratios of PCU with noncoated urea (NCU) compared with ammonium nitrate (AN) and NCU on wheat and double‐crop soybean yield. The experimental design was a factorial that included two N application rates (84 and 112 kg N ha−1), seven application dates (October–April), five N fertilizer source/ratios, and nontreated controls. Urea‐N release from PCU fertilizers applied on 15 October was <30% by 15 February in two of the three study years. Wheat yields were significantly (P ≤ 0.05) affected by the three‐way interactions of year × N source × N rate and year × N source × application date. In two of the three study years, yields were 450 to 500 kg ha−1 greater with an October application of 100% PCU compared to 100% NCU. Double‐crop soybean yields were not affected by preceding winter wheat N management.
Long‐Term Nitrogen and Tillage Effects on Soil Physical Properties under Continuous Grain Sorghum
Authors: Presley DeAnn R. , Sindelar Aaron J. , Buckley Meghan E. , Mengel David B.
Published: June 2012

Grain sorghum [Sorghum bicolor (L.) Moench] is an important grain crop grown in both highly productive and marginal areas in the central Great Plains because of the crop's ability to use the erratic precipitation observed in this region. More effective capture and storage of this limited rainfall is needed to improve the productivity and profitability of dryland agriculture. The objective of this study was to determine the effects of long‐term tillage and N fertilization on soil physical and hydraulic properties after long‐term continuous grain sorghum production. Variables included conventional tillage (CT) and no‐till (NT) and four rates of N fertilizer. Selected soil quality indicators included soil organic carbon (SOC), bulk density (BD), wet aggregate stability (WAS), and ponded infiltration. No‐till accumulated more SOC in the surface 0 to 5 cm, and was less dense at all depths than CT. When tillage was compared across all N rates, NT contained 30% greater SOC than CT at the 0 to 5 cm. Mean weight diameter (MWD) was larger with increasing N fertilization and eliminating tillage. Ponded infiltration rates were greatest for the high N fertilization rate under NT, and lowest for the 0 kg N ha−1 rate under CT. In this long‐term grain sorghum system, increasing N fertilization rate and NT both positively affected soil physical properties. These improvements in hydraulic properties will aid in more effectively capturing unpredictable precipitation, and further underscore the utility of NT management practices for the central Great Plains region.
Relevance of Pedigree, Historical Data, Dominance, and Data Unbalance for Selection Efficiency
Authors: Viana José Marcelo Soriano , DeLima Rodrigo Oliveira , Faria Vinícius Ribeiro , Mundim Gabriel Borges , de Resende Marcos Deon Vilela , e Silva Fabyano Fonseca
Published: June 2012

The objective of this study was to assess the impact of pedigree, historical data, dominance, and data unbalance on the estimation and precision of genetic variances and breeding values and on the selection efficiency in annual crop breeding. Expansion volume and grain yield from 12 trials of inbred progeny and four tests of non‐inbred families were used in the analyses. The S1 to S5 progeny trials were designed as incomplete blocks, the S6 progeny trials were designed as complete blocks, and the half‐ and full‐sib family trials were designed as lattices. The half‐sib, full‐sib, and inbred family models were fitted in across‐generation analyses. One complete and four reduced models were used to assess the relevance of pedigree, historical data, and dominance. Simulated plot losses of 30% in the half‐ and full‐sib progeny trials were used to study the influence of data unbalance. All analyses were performed using ASReml. Ignoring pedigree information or ancestor data and simulating plot losses determined relevant biases in estimating the additive and dominance variances, marked reduction in the precision of the predicted breeding values, significant changes in the classification of the breeding values, and errors in identifying superior individuals, i.e., a significant reduction in the selection efficiency. In contrast, excluding dominance had no significant effect on either the ranking of breeding values or selection efficiency. Our results revealed that best linear unbiased prediction including pedigree and historical data, based on a model with dominance, is the ideal method for genetic evaluation by plant breeders even when lost records are considered.
Variable Environment and Market Affect Optimal Nitrogen Management in Wheat and Cattle Production Systems
Authors: Zhang X. C. (John) , MacKown C. T. , Garbrecht J. D. , Zhang H. , Edwards J. T.
Published: June 2012

Fertilizer nitrogen use efficiency (NUE) is about 33% worldwide. The application of crop models has the potential to improve NUE by allowing managers to optimize and synchronize N supply with crop demand. We used a wheat (Triticum aestivum L.) grazing model to predict optimal N rates that maximize either grain yield for a grain‐only system or net economic return for a dual‐purpose system for selected climate, soil water reserve, and market conditions. Simulated probabilistic distributions of optimal fertilizer N rates for grain‐only wheat revealed a 55% chance that optimal N was <40 kg ha−1 when precipitation from August to February was <30 cm, and a 90% chance that optimal N was between 90 and 120 kg ha−1 when precipitation during the same period was >40 cm. This result supports a split N application with <45 kg ha−1 applied pre‐plant and additional N top‐dressed in February according to precipitation and yield potential. Dual‐purpose winter wheat with an initially wet soil profile required about 20, 60, 80, and 90 kg ha−1 of pre‐plant N to maximize cattle (Bos taurus) live weight gain for stocking densities of 1, 2, 2.5, and 3 head ha−1, and about 120 kg N ha−1 to maximize total net economic returns. In contrast, total optimal N for dual‐purpose wheat with an initially dry soil ranged from 0 to 90 kg ha−1, depending on climate. Precipitation between August and February was a good predictor of N requirement. Wheat grazing model was a useful tool for optimizing N management in north‐central Oklahoma.
Spring Nitrogen Fertilization of Ryegrass–Bermudagrass for Phytoremediation of Phosphorus‐Enriched Soils
Authors: Read John J.
Published: June 2012

Because annual ryegrass (Lolium multiflorum L.) exhibits increases in herbage P with increasing soil P, biomass response to N should influence phytoremediation of P‐enriched soils. Field plot (each 2 by 5 m) studies were conducted to determine the effect of six N schemes that provided 112 or 168 kg N ha−1 on uptake of P and soil test P (STP, 0–15‐cm depth) of double‐cropped bermudagrass [Cynodon dactylon L. (Pers.)] and ryegrass. Bermudagrass was previously fertilized with 9 and 18 Mg broiler litter ha−1 in 2004–2007, no litter was applied after 2007. At past litter rate of 9 Mg ha−1, total uptake of P averaged 48.5 kg ha−1 in 2008 and 51.7 kg ha−1 in 2009. Based on initial STP levels in 2007, results in 2009 indicated STP levels decreased by approximately 50 kg ha−1 yr−1, with reductions of 44% at 9 Mg litter ha−1 (104–58 mg kg−1) and 38% at 18 Mg litter ha−1 (173–108 mg kg−1). Averaged across years and litter rates, uptake of P in ryegrass was greater at 168 than 112 kg N ha−1 (35.4 vs. 29.4 kg ha−1, P < 0.01) and ranged from 35.8 kg ha−1 in scheme N5 to 26.7 kg ha−1 in scheme N1. Schemes N5 and N6, with a total rate of 168 kg N ha−1 in March and May, stimulated uptake of P in ryegrass and ryegrass–bermudagrass, but STP levels in 2009 were not lower than a single application of 112 kg N ha−1 in January and March.
Use of Surface Soil Moisture to Estimate Profile Water Storage by Polynomial Regression and Artificial Neural Networks
Authors: Bono Alfredo , Alvarez Roberto
Published: June 2012

Water storage in the soil profile is an important agronomic variable but its measuring is rather difficult for farmers in production fields. We tested the possibility of using samples from the upper soil layers, which are usually taken for soil fertility evaluation, for whole profile water storage estimation. A data set of 712 water profiles from the subhumid‐semiarid portion of the Pampas in Argentina was used, generated under a wide range of soil types, crops, tillage systems, soil cover, and rainfall scenarios. To calculate stored water, soil was sampled up to 140 cm in layers of 20 cm, water content was gravimetrically determined and bulk density also assessed. Polynomial regression and artificial neural networks were used for modeling, randomly partitioning the data set into 75% for model fit and 25% for independent testing. It was possible to estimate with good fit soil profile water storage using as independent variables in regression, or inputs in neural networks, water content in the upper three soil layers (0–20, 20–40, and 40–60 cm) and depth to petrocalcic layer in soils which have this type of horizon. Similar performance was attained with both modeling methods (R2 > 0.93, RMSE = 11% of mean water content). Other soil and environmental properties had only a minor impact on estimations and were dropped from models. Because of its simplicity, regression is the recommend method for estimation of water content in the soil profile for agronomist.
Soil Microbiology in Glyphosate‐Resistant Corn Cropping Systems
Authors: Lupwayi Newton Z. , Blackshaw Robert E.
Published: June 2012

Genetically modified herbicide resistant crops are commonly grown since their introduction in the 1990s, but growing these crops could affect soil microorganisms. We evaluated the effects of glyphosate‐resistant (GR) corn (Zea mays L.) and glyphosate application on soil microbial biomass carbon (MBC), β‐glucosidase enzyme activity (final season only), bacterial functional diversity, and bacterial community‐level physiological profiles (CLPPs) in corn monoculture in five seasons. We also determined if growing GR corn in crop rotations would alter these effects. In monoculture, the GR trait (GR corn vs. conventional corn) had no effects on MBC, β‐glucosidase activity, or functional diversity in any year. However, there were differences in CLPPs related to this trait in three seasons. Glyphosate application in monoculture increased MBC in corn rhizosphere in one season, and decreased MBC and bacterial diversity in bulk soil in another season. In crop rotations, GR corn (relative to conventional corn) decreased bacterial diversity and MBC in bulk soil in two seasons, and increased β‐glucosidase activity in corn rhizosphere and bacterial diversity in bulk soil in the final season. Growing GR corn in crop rotation compared to growing it in monoculture decreased MBC in corn rhizosphere in one season, but increased MBC and bacterial diversity in bulk soil in four seasons, and increased β‐glucosidase activity in corn rhizosphere and bulk soil in the final season. These results show that the GR technology had mostly no effects on soil microorganisms, had some inconsistent effects, and growing GR corn in crop rotation mostly mitigated any negative effects.
Methods to estimate irrigated reference crop evapotranspiration – a review
Authors: Kumar R. , Jat M. K. , Shankar V.
Published: June 2012

Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.
Efficient biodegradation of naphthalene by a newly characterized indigenous Achromobacter sp. FBHYA2 isolated from Tehran Oil Refinery Complex
Authors: Farjadfard Sima , Borghei Seyyed Mehdi , Hassani Amir Hessam , Yakhchali Bagher , Ardjmand Mehdi , Zeinali Majid
Published: June 2012

A bacterial strain, FBHYA2, capable of degrading naphthalene, was isolated from the American Petroleum Institute (API) separator of the Tehran Oil Refinery Complex (TORC). Strain FBHYA2 was identified as Achromobacter sp. based on physiological and biochemical characteristics and also phylogenetic similarity of 16S rRNA gene sequence. The optimal growth conditions for strain FBHYA2 were pH 6.0, 30 °C and 1.0% NaCl. Strain FBHYA2 can utilize naphthalene as the sole source of carbon and energy and was able to degrade naphthalene aerobically very fast, 48 h for 96% removal at 500 mg/L concentration. The physiological response of Achromobacter sp., FBHYA2 to several hydrophobic chemicals (aliphatic and aromatic hydrocarbons) was also investigated. No biosurfactant was detected during bacterial growth on any aliphatic/aromatic hydrocarbons. The results of hydrophobicity measurements showed no significant difference between naphthalene- and LB-grown cells. The capability of the strain FBHYA2 to degrade naphthalene completely and rapidly without the need to secrete biosurfactant may make it an ideal candidate to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated sites.
Estimation of Zn and Cu unit output loads from animal husbandry facilities
Authors: Abe Kaoru , Waki Miyoko , Suzuki Kazuyoshi , Kasuya Masahiro , Suzuki Ryouji , Itahashi Sunao , Banzai Kenji
Published: June 2012

Zinc (Zn) and copper (Cu) are toxic to aquatic organisms at very low concentrations that do not affect humans. We measured the daily output of Zn and Cu in wastewater from livestock farms to aquatic environments because waste from animal husbandry operations contains high levels of Zn and Cu. At most pig farms in Japan, a mixture of urine, some faeces, and service water is treated in onsite wastewater treatment facilities and discharged into a water body. Some dairy farms also have wastewater treatment facilities. We surveyed 21 pig farms and six dairy farms. The unit (i.e., per head) output load from piggery wastewater treatment facilities ranged from 0.13 to 17.8 mg/head/d for Zn and from 0.15 to 9.4 mg/head/d for Cu. Over 70% of pig farms had unit output loads of Zn and Cu below 6 and 2 mg/head/d, respectively. For dairy farms, the unit output load from wastewater treatment facilities was estimated at 1.8–3.6 mg/head/d for Zn and 0.6 mg/head/d for Cu. The unit output load for Zn from piggery wastewater treatment facilities was similar to that from treatment facilities for human waste. However, pig farms generally raise several thousand to tens of thousands of pigs; pig farms are therefore presumed to be a significant point source of Zn in rural areas.
Education in Accountancy and Social Control: Questions and Comments
Authors: Loeb Stephen E.
Published: June 2012

My paper considers two questions relating to the roles that education in college and university degree programs and in continuing professional education (CPE) programs play in the social control of the public accounting profession. These questions consider how: (1) educators should respond to the possibility that outside stakeholders might misinterpret the effect of ethics education in accounting degree programs in colleges and universities and ethics-related CPE, and (2) CPE should be used in the public accounting profession's disciplinary process. An assessment process and content similarity are suggested as ways to approach issues raised by the first question. CPE is most appropriate as a sanction when a Certified Public Accountant (CPA) in public accounting unintentionally violates an ethical standard of the public accounting profession and an effort is being made to rehabilitate the CPA. However, if a CPA in public accounting intentionally violates an ethical standard of the public accounting profession, the appropriateness of using CPE as a sanction in an effort to rehabilitate the CPA is controversial and requires research. Both questions and their discussion in the paper draw on comments in Waithe and Ozar (1990).
Surgical approach of complicated diverticulitis with colovesical fistula: technical note in a particular condition
Authors: Desiderio Jacopo , Trastulli Stefano , Listorti Chiara , Milani Diego , Cerroni Michele , Cochetti Giovanni , Cirocchi Roberto , Boselli Carlo , Parisi Amilcare , Mearini Ettore , Noya Giuseppe
Published: June 2012

Background: Diverticular disease of the colon is common in the Western world. With the first episode of diverticulitis, most patients will benefit from medical therapy, but in 10% to 20% of cases some complications will develop, such as intra-abdominal abscesses, obstructions, fistulas. In these conditions it is important to define the most appropriate surgical approach. Discussion: The management of diverticular disease has been successful owing to the advances in diagnostic methods, intensive care and surgical experience, but there is debate about the best treatment for some conditions. Fistulas complicating diverticulitis are the result of a localized perforation into adjacent viscera. In particular, the connection between the colon and the urinary tract is a serious anatomical abnormality that must be urgently corrected before a serious urinary infection results. Indications, timing and surgical procedures are determined by the severity of the disease and the patient’s general condition. Summary: Diverticular disease can lead to many complications. One of the most difficult to correct is an internal fistula, such as a colo-vesical fistula. The correct approach in cases where the disorder is clinically suspected has always been controversial, and the guidelines for sigmoid diverticulitis have not established the most appropriate method for diagnosis and treatment. At present, the surgical strategy for these cases requires interruption of the fistula and resection to remove the inflamed colonic segment, with or without primary anastomosis, focusing attention on the construction of the anastomosis to well vascularized and anatomically healthy tissues. It is clear, therefore, that establishing guidelines is difficult, because many pathological situations may be related to diverticulitis, and so, as our experience shows, the surgical approach has to be tailored to the patient’s general and local condition.
Infinite-dimensional Sylvester equations: Basic theory and application to observer design
Authors: Emirsajłow Zbigniew
Published: June 2012

Infinite-dimensional Sylvester equations: Basic theory and application to observer design

This paper develops a mathematical framework for the infinite-dimensional Sylvester equation both in the differential and the algebraic form. It uses the implemented semigroup concept as the main mathematical tool. This concept may be found in the literature on evolution equations occurring in mathematics and physics and is rather unknown in systems and control theories. But it is just systems and control theory where Sylvester equations widely appear, and for this reason we intend to give a mathematically rigorous introduction to the subject which is tailored to researchers and postgraduate students working on systems and control. This goal motivates the assumptions under which the results are developed. As an important example of applications we study the problem of designing an asymptotic state observer for a linear infinite-dimensional control system with a bounded input operator and an unbounded output operator.
An SQP trust region method for solving the discrete-time linear quadratic control problem
Authors: Mostafa El-Sayed
Published: June 2012

An SQP trust region method for solving the discrete-time linear quadratic control problem

In this paper, a sequential quadratic programming method combined with a trust region globalization strategy is analyzed and studied for solving a certain nonlinear constrained optimization problem with matrix variables. The optimization problem is derived from the infinite-horizon linear quadratic control problem for discrete-time systems when a complete set of state variables is not available. Moreover, a parametrization approach is introduced that does not require starting a feasible solution to initiate the proposed SQP trust region method. To demonstrate the effectiveness of the method, some numerical results are presented in detail.
Adaptive control of cluster-based Web systems using neuro-fuzzy models
Authors: Zatwarnicki Krzysztof
Published: June 2012

Adaptive control of cluster-based Web systems using neuro-fuzzy models

A significant development of Web technologies requires the application of more and more complex systems and algorithms for maintaining high quality of Web services. Presently, not only simple decision-making tools but also complex adaptation algorithms using artificial intelligence techniques are applied for controlling HTTP request traffic. The paper presents a new LFNRD (Local Fuzzy-Neural Adaptive Request Distribution) algorithm for request distribution in cluster-based Web systems using neuro-fuzzy models of Web servers in the decision-making process. The neuro-fuzzy model which is applied is discussed in detail and a design of the Web switch using the proposed solution is presented. Finally, a testbed is described and the results of a comparative simulation study on the LFNRD algorithm, and other algorithms known from the literature and used in the industry, are presented and discussed.
Existence and determination of the set of Metzler matrices for given stable polynomials
Authors: Kaczorek Tadeusz
Published: June 2012

Existence and determination of the set of Metzler matrices for given stable polynomials

The problem of the existence and determination of the set of Metzler matrices for given stable polynomials is formulated and solved. Necessary and sufficient conditions are established for the existence of the set of Metzler matrices for given stable polynomials. A procedure for finding the set of Metzler matrices for given stable polynomials is proposed and illustrated with numerical examples.
Straight-lines modelling using planar information for monocular SLAM
Authors: Santana André , Medeiros Adelardo
Published: June 2012

Straight-lines modelling using planar information for monocular SLAM

This work proposes a SLAM (Simultaneous Localization And Mapping) solution based on an Extended Kalman Filter (EKF) in order to enable a robot to navigate along the environment using information from odometry and pre-existing lines on the floor. These lines are recognized by a Hough transform and are mapped into world measurements using a homography matrix. The prediction phase of the EKF is developed using an odometry model of the robot, and the updating makes use of the line parameters in Kalman equations without any intermediate stage for calculating the distance or the position. We show two experiments (indoor and outdoor) dealing with a real robot in order to validate the project.
A general on-the-fly algorithm for modifying the kinematic tree hierarchy
Authors: Stępień Jakub , Polański Andrzej , Wojciechowski Konrad
Published: June 2012

A general on-the-fly algorithm for modifying the kinematic tree hierarchy

When conducting a dynamic simulation of a multibody mechanical system, the model definition may need to be altered during the simulation course due to, e.g., changes in the way the system interacts with external objects. In this paper, we propose a general procedure for modifying simulation models of articulated figures, particularly useful when dealing with systems in time-varying contact with the environment. The proposed algorithm adjusts model connectivity, geometry and current state, producing its equivalent ready to be used by the simulation procedure. Furthermore, we also provide a simple usage scenario—a passive planar biped walker.
Improving prediction models applied in systems monitoring natural hazards and machinery
Authors: Sikora Marek , Sikora Beata
Published: June 2012

Improving prediction models applied in systems monitoring natural hazards and machinery

A method of combining three analytic techniques including regression rule induction, thek-nearest neighbors method and time series forecasting by means of the ARIMA methodology is presented. A decrease in the forecasting error while solving problems that concern natural hazards and machinery monitoring in coal mines was the main objective of the combined application of these techniques. The M5 algorithm was applied as a basic method of developing prediction models. In spite of an intensive development of regression rule induction algorithms and fuzzy-neural systems, the M5 algorithm is still characterized by the generalization ability and unbeatable time of data model creation competitive with other systems. In the paper, two solutions designed to decrease the mean square error of the obtained rules are presented. One consists in introducing into a set of conditional variables the so-called meta-variable (an analogy to constructive induction) whose values are determined by an autoregressive or the ARIMA model. The other shows that limitation of a data set on which the M5 algorithm operates by thek-nearest neighbor method can also lead to error decreasing. Moreover, three application examples of the presented solutions for data collected by systems of natural hazards and machinery monitoring in coal mines are described. In Appendix, results of several benchmark data sets analyses are given as a supplement of the presented results.
The isolation of bioactive flavonoids from Jacaranda obtusifolia H. B. K. ssp. rhombifolia (G. F. W. Meijer) Gentry
Authors: Khamsan Sorachai , Liawruangrath Saisunee , Teerawutkulrag Aphiwat , Pyne Stephen , Garson Mary , Liawruangrath Boonsom
Published: June 2012

The isolation of bioactive flavonoids from Jacaranda obtusifolia H. B. K. ssp. rhombifolia (G. F. W. Meijer) Gentry

The paper describes the bioassay-guided isolation, structure elucidation and anticancer evaluation of five flavonoids (-)-liquiritigenin (1), (-)-neoliquiritin (2), isoliquiritigenin (3), isoliquiritin (4) and formononetin (5) from the twigs of Jacaranda obtusifolia H. B. K. ssp. rhombifolia (G. F. W. Meijer) Gentry. The structures were elucidated based on 1H, 13C NMR, comprehensive 2D NMR, MS analyses and comparison with previously reported spectral data. Compounds 1 and 3 were demonstrated to be inhibitory in vitro against NCI-H187 (small cell lung cancer) with IC50 values of 30.1 and 16.6 μg mL-1, respectively. The isolates were non-cytotoxic to Vero cells (African green monkey kidney).
Simultaneous determination of methocarbamol and ibuprofen or diclofenac potassium using mean centering of the ratio spectra method
Authors: Ali Nouruddin , Hegazy Maha , Abdelkawy Mohamed , Abdelaleem Eglal
Published: June 2012

Simultaneous determination of methocarbamol and ibuprofen or diclofenac potassium using mean centering of the ratio spectra method

Accurate and sensitive methods were developed for simultaneous determination of methocarbamol and ibuprofen or diclofenac potassium in their binary mixtures, and in the presence of a methocarbamol related substance (guaifenesin) using mean centering of the ratio spectra method. The results obtained were statistically compared with the reported HPLC methods; no significant difference between the proposed methods and the reported methods was found regarding either accuracy or precision.
Equivalence Scale in Terms of Polish Households' Source of Income
Authors: Ulman Paweł
Published: June 2012

Equivalence Scale in Terms of Polish Households' Source of Income

The paper presents a comparison of the costs of Polish households by their main source of income. In order to compare these costs the author estimated three kinds of equivalence scales using the Engel method, ELES (Extended Linear Expenditure System), the demand equation and the Bernoulli well-being function. Estimation for household groups determined on account of the main source of income produced by the scales confirmed differences in households' maintenance costs compared to the costs of the reference household. A comparison of the values of equivalence scales revealed a similarity of the results produced by the ELES and the Bernoulli methods which differed from the results obtained by means of the Engel method.
Maximal isokinetic peak torque and emg activity determined by shorter ranges of motion
Authors: Oliveira Anderson S.C. , Corvino Rogério B. , Gonçalves Mauro , Caputo Fabrizio , Denadai Benedito S.
Published: June 2012

Purpose

Isokinetic tests are often applied to assess muscular strength and EMG activity, however the specific ranges of motion used in testing (fully flexed or extended positions) might be constrictive and/or be painful for patients with injuries or undergoing rehabilitation. The aim of this study was to examine the effects of different ranges of motion (RoM) when determining maximal EMG during isokinetic knee flexion and extension with different types of contractions and velocities.

Methods

Eighteen males had EMG activity recorded on the vastus lateralis, vastus medialis, semitendinosus and biceps femoris muscles during five maximal isokinetic concentric and eccentric contractions for the knee flexors and extensors at 60° · s–1 and 180° · s–1. The root mean square of EMG was calculated at three different ranges of motion: (1) a full range of motion (90°–20° [0° = full knee extension]); (2) a range of motion of 20° (between 60°–80° and 40°–60° for knee extension and flexion, respectively) and (3) at a 10° interval around the angle where peak torque is produced. EMG measurements were statistically analyzed (ANOVA) to test for the range of motion, contraction velocity and contraction speed effects. Coefficients of variation and Pearson’s correlation coefficients were also calculated among the ranges of motion.

Results

Predominantly similar (p > 0.05) and well-correlated EMG results (r > 0.7, p < 0.001) were found among the ranges of motion. However, a lower coefficient of variation was found for the full range of motion, while the 10° interval around peak torque at 180° · s–1 had the highest coefficient, regardless of the type of contraction.

Conclusions

Shorter ranges of motion at around the peak torque angle provides a reliable indicator when recording EMG activity during maximal isokinetic parameters. It may provide a safer alternative when testing patients with injuries or undergoing rehabilitation.
Analysis of body posture between young football players and their untrained peers
Authors: Grabara Małgorzata
Published: June 2012

Purpose

The aim of this study was to analyze the body posture of young football players and their untrained peers.

Methods

A group of 73 football players and 78 untrained boys, all aged between 11 and 14 years, were studied by measuring body posture indices with computer posturography (the MORIE technique). Spinal angles and curvatures in the sagittal plane and body posture asymmetry in the frontal and transversal plane were measured. Body height and mass and BMI were also determined.

Results

Compared to the untrained boys, the group of football players had lower BMI. The position of pelvis in the frontal plane was more symmetrical (p < 0.001) in football players, but the alignment of the remaining measured parameters was similar between the two groups except for the horizontal symmetry of the waist triangles (a higher incidence of symmetry in some ages groups of football players) and the horizontal symmetry of the shoulder blades (a higher incidence of asymmetry in some ages groups of football players). A postural symmetry index that was created for this study did not find any differentiation among the studied groups. The spinal alignment of the football players featured a more flattened lumbar lordosis.

Conclusions

Previously conducted studies on the body posture of young athletes are still not ample and complete, while the results do not clearly indicate the development of posture when subjected to sports training.
A comparative analysis of the anthropometric method and bioelectrical impedance analysis on changes in body composition of female volleyball players during the 2010/2011 season
Authors: Buśko Krzysztof , Lipińska Monika
Published: June 2012

Purpose

The aim of this study was to observe the changes in body composition by using two measurement methods – anthropometric analysis and bioelectrical impedance analysis (BIA) – on a group female volleyball players and to compare the results of both methods.

Methods

Eleven female volleyball players participated in this study during the 2010/2011 season. Measurements of body composition were performed with an electronic body composition analyzer (BIA method) adjusted for STANDARD physical activity levels and then using the anthropometric method as per Piechaczek’s formula. Total lean body mass (LBM), total body fat content (FAT) and body water content were measured. Measurements were taken before preseason training (Measurement 0), one week before the end of preseason training (Measurement 1), after the first (Measurement 2) and the second (Measurement 3) half of the competitive season and four weeks after the seasons’ playoffs during the offseason (Measurement 4). Additionally, during Measurement 4, body composition measured by the BIA method was adjusted for ATHLETIC physical activity levels.

Results

Body mass, lean body mass and body water content did not change throughout the analyzed period. Body fat mass, as determined by BIASTANDARD, increased from 20.7 ± 5.3 kg (Measurement 0) to 22.2 ± 5.0 kg (Measurement 1) but subsequently decreased to 21.2 ± 5.7 kg (Measurement 2) and remained at this level until the end of the competitive season. In the case of body fat as measured by the anthropometric method, a significant increase in fat was observed from 18.4 ± 3.0 kg to 19.3 ± 3.4 kg and then from 19.5 ± 3.5 kg to 19.8 ± 3.6 kg. Analysis of LBM and FAT values found significant differences between the values obtained using the BIA method at the ATHLETIC physical activity level and the results registered at the STANDARD level and those recorded by use of the anthropometric method.

Conclusions

The results obtained using the BIA method set at the STANDARD mode of physical activity and those by the anthropometric method did not significantly differ. Significant correlation between the values obtained by the BIA method and anthropometric method was found.
Lake Engure catchment area as an example of the interaction of natural conditions, settlement pattern and economic activities
Authors: Strautnieks Ivars , Grīne Ineta
Published: June 2012

Lake Engure catchment area as an example of the interaction of natural conditions, settlement pattern and economic activities

The authors have written this paper as an overview of the area, which includes earlier published data and the results of a new, original research. It covers the geological structure, including a characterisation of the geology of the Sub-Quaternary surface. Described in greater detail are the Quaternary cover and the surface relief, as well as the hypsometry, which in many locations directly influence the conditions of surface drainage, soil development and landscape characteristics. Based on the morphology and internal structure of the relief, the main stages in the formation of the relief are also outlined, in effect marking temporal differences in landscape development. The influence of these factors, as well as a string of other natural factors (groundwater and surface drainage, the proximity of the sea) within distinct parts of the study area, explain the character of human economic activities, the development of settlement and the traditions that have continued over the centuries. Several different areas are clearly distinguishable in functional terms: 1) the area where farming is the characteristic activity, 2) the area used for fishing and recreation, 3) forested areas, with soils unsuitable for agriculture. The form and intensity of land use also determine the distribution of settlements and population size.
Reconstruction of past anthropogenic impact intensity in Lake Engure using sedimentary record analysis
Authors: Kļaviņš Māris , Pujāte Agnese , Kokorīte Ilga , Kalniņa Laimdota , Rodinovs Valērijs , Ansone Linda , Mažeika Jonas , Jankēvica Maruta , Bogans Egils , Švāgere Anda
Published: June 2012

Reconstruction of past anthropogenic impact intensity in Lake Engure using sedimentary record analysis

Environmental pollution with trace elements is considered as one of the most important environmental problems. Analysis of trace element accumulation in sedimentary phases of lakes may reflect the overall regional pollution level, and analysis of trace element accumulation patterns in sediment profiles can help to reconstruct the history of anthropogenic impact. The aim of this study was to analyse trace element concentrations in sediments of Lake Engure in Latvia and to determine factors influencing their availability. The metal concentrations in sediments of Lake Engure are at background levels, especially compared with metal concentrations in West European countries. However, the change in element concentration in sedimentary profiles provides information about trends of recent accumulation (within the last 100 years) and on the balance between natural and human-induced accumulation processes.
Influence of waste liquors of mildronate production on yield and quality of winter rapeseed
Authors: Bremanis Gunārs , Maļecka Solveiga
Published: June 2012

Influence of waste liquors of mildronate production on yield and quality of winter rapeseed

The effect of mother liquors obtained in one production stage of the popular medicinal preparation Mildronate on yield and quality of winter rape (Brassica napus L.) grown for biofuel was tested. The mother liquors contain quaterine-type compounds, which are known to stimulate growth of lupines. In the three-year study, Mildronate mother liquors were sprayed on winter rape. The yield and fat content of rape was determined. Mother liquor contains small amounts of methyl acrylate. However, this compound was not found in rapeseed, stalks and soil. Mother liquors spray had a positive effect on soil microorganisms. In the period from initiation of flowering to maximum flowering stage, spraying with mother liquors, as well as with quaterine-M and isopropanol (basic substance of mother liquor), in most cases had a low (around 10%) positive effect on rape yield and a very small impact on the fat content in rape grain. The effects differed among years, suggesting interaction with weather conditions. The determined optimal mother liquors dosages were quite wide, from 0.4 to 10 L ha-1.