bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of microRNAs in directing therapy and evaluating treatment response in colorectal cancer
Authors: Andreoli Silmara Cristiane da Silveira , Gasparini Nina Jardim , Carvalho Gisele Pereira de , Garicochea Bernardo , Pogue Robert Edward , Andrade Rosângela Vieira de
Published: June 2014

Colorectal cancer is the third most common cancer worldwide. Survival and prognosis depend on tumor stage upon diagnosis, and in more than 50% of cases, the tumor has already invaded adjacent tissues or metastasis has occurred. Aiming to improve diagnosis, clinical prognosis and treatment of patients with colorectal cancer, several studies have investigated microRNAs as molecular markers of the disease due to their potential regulatory functions on tumor suppressor genes and oncogenes. This review aimed to summarize the main topics related to the use of microRNAs in diagnosis, clinical prognosis and evaluating treatment response in colorectal cancer.
Influence of gastric emptying on the control of postprandial glycemia: physiology and therapeutic implications
Authors: Tambascia Marcos Antonio , Malerbi Domingos Augusto Cherino , Eliaschewitz Freddy Goldberg
Published: June 2014

The maintenance of glucose homeostasis is complex and involves, besides the secretion and action of insulin and glucagon, a hormonal and neural mechanism, regulating the rate of gastric emptying. This mechanism depends on extrinsic and intrinsic factors. Glucagon-like peptide-1 secretion regulates the speed of gastric emptying, contributing to the control of postprandial glycemia. The pharmacodynamic characteristics of various agents of this class can explain the effects more relevant in fasting or postprandial glucose, and can thus guide the individualized treatment, according to the clinical and pathophysiological features of each patient.
Selenomethionine and Total Methionine Ratio is Conserved in Seed Proteins of Selenium‐Treated and Nontreated Soybean, Flax, and Potato
Authors: Fofana B. , Main D. , Ghose K. , Grimmett M. , Peters R. D. , Martin R.A. , Mester Z. , Yang L. , Locke S. , Sweeney M.
Published: June 2014

Crop biofortification with Se is widely accepted. However, little is known about the efficiency of selenomethionine (Se‐Met) incorporation into the seed and tuber protein fraction of crops. Here, we report on the efficiency of Se incorporation into the seed and tuber protein fraction of soybean, flax, and potato and the putative identity of some of the proteins that are likely targets for this random pretranslation modification. Soybean, flax, and potato plants received Se using different sodium selenate application methods and rates, and Se‐Met was determined in seed, tuber, and their protein fractions. Selenium content in seed and tuber tissues and in protein fractions was increased by 2 to 86 times. The methionine (Met) pool was increased, as was the proportion of Se‐Met in the Met pool, but the ratio of Se‐Met:total Met was well conserved (1:1) between the treated and nontreated plants. After two‐dimensional (2D) protein electrophoresis, five protein spots were identified as glycinin, trypsin inhibitor (soybean), patatin‐3‐Kuras‐1, patain‐B2, and phosphoenol carboxy kinase (potato), none of which showed S to Se substitution in their primary structure. Linking Se and three stress markers in fresh tuber extracts, glutathione (GSH) level, glutathione peroxidase (GPx), and glutathione reductase (GR) activities were increased by 20 to 35%. The data showed low protein modification in these non‐Se‐accumulator crops and indicated that rates of 5 to 10 g ha–1 Se, through foliar application, may ensure not only an adequate daily intake levels for humans but may also activate antioxidant enzyme systems within the tuber tissue.
Cold Tolerance in Two Large Maize Inbred Panels Adapted to European Climates
Authors: Revilla Pedro , Rodríguez Víctor Manuel , Ordás Amando , Rincent Renaud , Charcosset Alain , Giauffret Catherine , Melchinger Albrecht E. , Schön Chris‐Carolin , Bauer Eva , Altmann Thomas , Brunel Dominique , Moreno‐González Jesús , Campo Laura , Ouzunova Milena , Laborde Jacques , Álvarez Ángel , Ruíz de Galarreta José Ignacio , Malvar Rosa Ana
Published: June 2014

Maize (Zea mays L.) for northern growing areas requires cold tolerance for extending the vegetative period. Our objectives were to evaluate two large panels of maize inbred lines adapted to Europe for cold tolerance and to estimate the effects of cold‐related traits on biomass production. Two inbred panels were evaluated for cold tolerance per se and in testcrosses under cold and control conditions in a growth chamber and under field conditions. Comparisons of inbreds and groups of inbreds were made taking into account the single nucleotide polymorphisms (SNP)‐based genetic structure of the panels, and the factors affecting biomass production were studied. Eight flint and one dent inbred with diverse origins were the most cold tolerant. The most cold‐tolerant dent and flint groups were the Iodent Ph207 and the Northern Flint D171 groups, respectively. The relationships between inbred per se and testcross performance and between controlled and field conditions were low. Regressions with dry matter yield in the field as dependent variable identified plant height (R2 = 0.285) as the main independent variable, followed by quantum efficiency of photosystem II (R2 = 0.034) and other traits with minor contributions. Cold‐tolerance–related traits had low and negative effects on dry matter yield. Models intending the prediction of final performance from traits scored in early developmental stages are not expected to be precise enough for breeding. For improving cold tolerance, inbreds released from crosses among the No Iodent group and the Northern Flint group may show high combining ability, as well as between both groups and the Northern Flint D171 group.
Regularized nonnegative matrix factorization: Geometrical interpretation and application to spectral unmixing
Authors: Zdunek Rafał
Published: June 2014

Nonnegative Matrix Factorization (NMF) is an important tool in data spectral analysis. However, when a mixing matrix or sources are not sufﬁciently sparse, NMF of an observation matrix is not unique. Many numerical optimization algorithms, which assure fast convergence for speciﬁc problems, may easily get stuck into unfavorable local minima of an objective function, resulting in very low performance. In this paper, we discuss the Tikhonov regularized version of the Fast Combinatorial NonNegative Least Squares (FC-NNLS) algorithm (proposed by Benthem and Keenan in 2004), where the regularization parameter starts from a large value and decreases gradually with iterations. A geometrical analysis and justiﬁcation of this approach are presented. The numerical experiments, carried out for various benchmarks of spectral signals, demonstrate that this kind of regularization, when applied to the FC-NNLS algorithm, is essential to obtain good performance.
Tikhonov regularization and constrained quadratic programming for magnetic coil design problems
Authors: Garda Bartłomiej , Galias Zbigniew
Published: June 2014

In this work, the problem of coil design is studied. It is assumed that the structure of the coil is known (i.e., the positions of simple circular coils are ﬁxed) and the problem is to ﬁnd current distribution to obtain the required magnetic ﬁeld in a given region. The unconstrained version of the problem (arbitrary currents are allowed) can be formulated as a Least-SQuares (LSQ) problem. However, the results obtained by solving the LSQ problem are usually useless from the application point of view. Moreover, for higher dimensions the problem is ill-conditioned. To overcome these difﬁculties, a regularization term is sometimes added to the cost function, in order to make the solution smoother. The regularization technique, however, produces suboptimal solutions. In this work, we propose to solve the problem under study using the constrained Quadratic Programming (QP) method. The methods are compared in terms of the quality of the magnetic ﬁeld obtained, and the power of the designed coil. Several 1D and 2D examples are considered. It is shown that for the same value of the maximum current the QP method provides solutions with a higher quality magnetic ﬁeld than the regularization method.
Automatic speech signal segmentation based on the innovation adaptive filter
Authors: Makowski Ryszard , Hossa Robert
Published: June 2014

Speech segmentation is an essential stage in designing automatic speech recognition systems and one can ﬁnd several algorithms proposed in the literature. It is a difﬁcult problem, as speech is immensely variable. The aim of the authors’ studies was to design an algorithm that could be employed at the stage of automatic speech recognition. This would make it possible to avoid some problems related to speech signal parametrization. Posing the problem in such a way requires the algorithm to be capable of working in real time. The only such algorithm was proposed by Tyagi et al., (2006), and it is a modiﬁed version of Brandt’s algorithm. The article presents a new algorithm for unsupervised automatic speech signal segmentation. It performs segmentation without access to information about the phonetic content of the utterances, relying exclusively on second-order statistics of a speech signal. The starting point for the proposed method is time-varying Schur coefﬁcients of an innovation adaptive ﬁlter. The Schur algorithm is known to be fast, precise, stable and capable of rapidly tracking changes in second order signal statistics. A transfer from one phoneme to another in the speech signal always indicates a change in signal statistics caused by vocal track changes. In order to allow for the properties of human hearing, detection of inter-phoneme boundaries is performed based on statistics deﬁned on the mel spectrum determined from the reﬂection coefﬁcients. The paper presents the structure of the algorithm, deﬁnes its properties, lists parameter values, describes detection efﬁciency results, and compares them with those for another algorithm. The obtained segmentation results, are satisfactory.
Artificial intelligence methods in diagnostics of analog systems
Authors: Bilski Piotr , Wojciechowski Jacek
Published: June 2014

The paper presents the state of the art and advancement of artiﬁcial intelligence methods in analog systems diagnostics. Firstly, the diagnostic domain is introduced and its problems explained. Then, computational intelligence approaches usable for fault detection and identiﬁcation are reviewed. Particular groups of methods are presented in detail, explaining their usefulness and drawbacks. Examples, such as the induction motor or the electronic ﬁlter, are provided to show the applicability of the presented approaches for monitoring the state of analog objects from engineering domains. The discussion section reviews the presented approaches, their future prospects and problems to be solved.
Selection of search strategies for solving 3-SAT problems
Authors: Pułka Andrzej
Published: June 2014

The paper concerns the problem of Boolean satisﬁability checking, which is recognized as one of the most important issues in the ﬁeld of modern digital electronic system veriﬁcation and design. The paper analyzes different strategies and scenarios of the proving process, and presents a modiﬁed and extended version of the author’s FUDASAT algorithm. The original FUDASAT methodology is an intuitive approach that employs a commonsense reasoning methodology. The main objective of the work is to investigate the SAT-solving process and try to formulate a set of rules controlling the reasoning process of the FUDASAT inference engine. In comparison with the author’s previous works, the paper introduces new mechanisms: hypergraph analysis, multiple variable assignments and search space pruning algorithms. The approach considers only 3-SAT class functions, although a generalization of the method is discussed as well. The presented approach has been tested on various benchmarks and compared with the original pure FUDASAT algorithm as well as with other algorithms known from the literature. Finally, the beneﬁts of the proposed SAT solving technique are summarized.
A 2D system approach to the design of a robust modified repetitive-control system with a dynamic output-feedback controller
Authors: Zhou Lan , She Jinhua , Zhou Shaowu
Published: June 2014

This paper is concerned with the problem of designing a robust modiﬁed repetitive-control system with a dynamic output feedback controller for a class of strictly proper plants. Employing the continuous lifting technique, a continuous-discrete two-dimensional (2D) model is built that accurately describes the features of repetitive control. The 2D control input contains the direct sum of the effects of control and learning, which allows us to adjust control and learning preferentially. The singular-value decomposition of the output matrix and Lyapunov stability theory are used to derive an asymptotic stability condition based on a Linear Matrix Inequality (LMI). Two tuning parameters in the LMI manipulate the preferential adjustment of control and learning. A numerical example illustrates the tuning procedure and demonstrates the effectiveness of the method.
Design of a multivariable neural controller for control of a nonlinear MIMO plant
Authors: Bańka Stanisław , Dworak Paweł , Jaroszewski Krzysztof
Published: June 2014

The paper presents the training problem of a set of neural nets to obtain a (gain-scheduling, adaptive) multivariable neural controller for control of a nonlinear MIMO dynamic process represented by a mathematical model of Low-Frequency (LF) motions of a drillship over the drilling point at the sea bottom. The designed neural controller contains a set of neural nets that determine values of its parameters chosen on the basis of two measured auxiliary signals. These are the ship’s current forward speed measured with respect to water and the systematically calculated difference between the course angle and the sea current (yaw angle). Four different methods for synthesis of multivariable modal controllers are used to obtain source data for training the neural controller with parameters reproduced by neural networks. Neural networks are designed on the basis of 3650 modal controllers obtained with the use of the pole placement technique after having linearized the model of LF motions made by the vessel at its nominal operating points in steady states that are dependent on the speciﬁed yaw angle and the sea current velocity. The ﬁnal part of the paper includes simulation results of system operation with a neural controller along with conclusions and ﬁnal remarks.
An efficient algorithm for adaptive total variation based image decomposition and restoration
Authors: Liu Xinwu , Huang Lihong
Published: June 2014

With the aim to better preserve sharp edges and important structure features in the recovered image, this article researches an improved adaptive total variation regularization and H−1 norm ﬁdelity based strategy for image decomposition and restoration. Computationally, for minimizing the proposed energy functional, we investigate an efﬁcient numerical algorithm—the split Bregman method, and brieﬂy prove its convergence. In addition, comparisons are also made with the classical OSV (Osher–Sole–Vese) model (Osher et al., 2003) and the TV-Gabor model (Aujol et al., 2006), in terms of the edge-preserving capability and the recovered results. Numerical experiments markedly demonstrate that our novel scheme yields signiﬁcantly better outcomes in image decomposition and denoising than the existing models.
Application of the Autocorrelation Function and Fractal Geometry Methods for Analysis of MFM Images
Authors: Bramowicz M. , Kulesza S. , Czaja P. , Maziarz W.
Published: June 2014

Presented work is focused on the use of correlation methods for numerical analysis of magnetic stray field over the surface of materials. Obtained results extend our previous findings about application of the autocorrelation function and the fractal analysis for characterization of magnetic surfaces. Several domain images are recorded at various tip-sample gaps (i.e. the lift heights), and then their average widths were extrapolated down to the zero distance in order to estimate the width seen right on the surface. Apart from that, fractal parameters were derived from autocorrelation function, which turned out to be sensitive to the lift height, and might constitute universal measure (the critical lift height), above which the MFM signal became dominated by thermal noises and non-magnetic residual interactions.
Thin Wall Ductile Iron Castings as Substitutes for Aluminium Alloy Castings
Authors: Fraś E. , Górny M. , Lopez H.
Published: June 2014

The paper discusses the reasons behind current trends for substituting cast iron castings by aluminum alloys. In particular it is shown that it is possible to produce thin wall castings (control arms, cantilevers and rotors) made of ductile iron without the development of chills, cold laps or misruns, and with a strength to weight ratio of up 87 MPa cm3/g. In addition, austenitizing at 900 °C for 20 minutes and then austempering in a salt bath at 350 °C for 15 minutes promotes the development of a fully ausferritic matrix in thin wall castings with a the strength to weight ratio increase of up to 154 MPa cm3/g. Finally, it is shown that thin wall castings made of ductile or austemperded cast iron can be lighter and with superior mechanical properties then their substitutes made of aluminum alloy.
Structure and Mechanical Properties of AlMg4.5 And AlMg4.5Mn Wires Extruded by Kobo Method
Authors: Jaskowski M. , Pieła K. , Błaz L.
Published: June 2014

The influence of the number of extrusion steps in KoBo method (at the same total extrusion ratio of λ = 100) on structure, mechanical properties and work hardening characteristics of AlMg4.5 and AlMg4.5Mn (AA5083) alloys was investigated. It was found that one-step extrusion leads to the formation of recrystallised structure of the material, while the use of two-step extrusion yields a fibrous structure of a “mixed” type, i.e. containing areas where the intensive recovery effects are associated with partially recrystallised structure. As a consequence, the strength properties of the latter extrudate are much higher in both as extruded state and after the subsequent cold rolling. In all cases, the tensile stress-strain curves of the extrudates show the flow stress serrations that are typical for the Portevin - LeChatelier (P-L) effect. In a few tensile tests, the P-L effect was preceded by the plastic flow instability being typical for the occurrence of Lüders bands. Both AlMg4.5 and AlMg4.5Mn extruded wires show a monotonic increase of the work hardening that results from the following cold deformation in the groove rolling.
Progress in Fabrication Technology of Silver-Based Contact Materials with Particular Account of the Ag-Re and Ag-SnO2Bi2O3 Composites
Authors: Księzarek S. , Woch M. , Kołacz D. , Kamińska M. , Borkowski P. , Walczuk E.
Published: June 2014

The paper outlines technologies currently used for the production of the Ag-Re10 and Ag-SnO2Bi2O3 contact materials in a form of wires and solid and bimetallic rivets. Their characteristic parameters, including physical and mechanical properties and microstructure, are given. It has been found that the level of these parameters, particularly electrical properties (resistance to electric arc erosion), is unsatisfactory considering the present requirements, which applies mainly to the new Ag-Re10 [wt%] alloy, so far not fully technologically mastered. Therefore, under this work a new method for the production of this type of materials has been designed and the related research works were undertaken. The new-generation contact materials in a form of nanostructured composites will be characterised by similar chemical compositions as those specified above but with increased functional properties, including enhanced resistance to arc erosion. In this paper preliminary results of the examination of structure and properties of semi-products obtained by new technology based on powder metallurgy techniques are presented. Conditions for pressure consolidation and plastic consolidation applied for material processing into wires and rivets (solid and bimetallic) have been determined.
Short-Time Ageing of MS350 Maraging Steel with and Without Plastic Deformation
Authors: Marcisz J. , Stępień J.
Published: June 2014

The age hardening behaviour of MS350 maraging steel both in undeformed specimens and in specimens deformed immediately after ageing was studied. Experiments of short-time (15, 30 and 60 s) ageing at temperature up to 600°C were performed. It was found that after ageing at 480-500°C for 15-60 s without deformation the hardness reached the 450-525 HV. The time of ageing at 600°C to reach hardness 600 HV was 15 seconds. No precipitation in specimen aged at 500°C for 60 s was found in TEM and HRTEM investigations. Deformation immediately after ageing intensifies the process of hardening caused by temporary increase of temperature and increase of dislocation density. The hardness of specimens aged for 30 s and then deformed at 480-550°C was similar to the hardness at peak aged conditions (480°C/4h) and reached 600-630 HV. Material produced in industrial trials of cold forward flow forming and following laboratory ageing was analyzed. Increase of hardness from 370 HV to 590-630 HV for specimens taken from thin walled flow formed tube as a result of ageing at 460-490°C for 30 minutes occurred.
Mechanical and Structural Behavior of Copper Subjected to the Flow Forming Process
Authors: Pawlicki M. , Bochniak W.
Published: June 2014

This work paper presents the results of HV 0.5 microhardness measurements and structural documentation of copper before and after the concurrent elongating flow forming process. No strain work hardening of products was noted. The cause of this behavior was recognized to be the location of strain strain localization in shear bands compounded by a change of the strain path imposed by the flow forming process. The dominance of this plastic flow mechanism makes it possible to conduct a technological process encompassing thinning of product walls with omission of expensive inter-operational softening heat treatment.
Application of Fast Fourier Transform (FFT) in the Analysis of a Welding Current Instantaneous Values Waveforms during Welding with a Covered Electrode
Authors: Słania J. , Ślązak B. , Fidali M.
Published: June 2014

The article presents the process of production of coated electrodes and their welding properties. The factors concerning the welding properties and the currently applied method of assessing are given. The methodology of the testing based on measuring and recording of instantaneous values of welding current and welding arc voltage is discussed. The article presents the application of Fast Fourier Transform (FFT) for the analysis of instantaneous values of welding current and welding arc voltage. The results of coated electrodes welding properties are compared. Finally the conclusions drawn from the research are presented.
The Microstructure and Properties of Low-Carbon PM Mn-Cr-Mo Steels Sintered under Different Conditions
Authors: Sułowski M. , Ciaś A. , Pieczonka T.
Published: June 2014

The paper presents the effect of sintering conditions on the microstructure and mechanical properties of low-carbon Mn-Cr-Mo PM steels. It was proved there is no effect of tempering temperature on the properties of Astaloy CrL-base steels, sintered at 1250°C in 5%H2-95%N2 mixture as compared with the properties of those sintered at 1120°C. The properties of Astaloy CrM-based steels, sintered at 1250°C in air were comparable or higher to Astaloy CrL-based steels. The addition of lump of ferromanganese was not sufficient for metal oxides reduction. The structure investigation confirmed the earlier observations that Mn-Cr-Mo PM steels have predominantly martensitic or martensitic/bainitic microstructure.
Thermodynamic Description of Ternary Fe-B-X Systems. Part 1: Fe-B-Cr
Authors: Miettinen J. , Vassilev G.
Published: June 2014

A thermodynamic description of the Fe-B-Cr system is developed in the context of a new Fe-B-X (X = Cr, Ni, Mn, Si, Ti, V, C) database. The thermodynamic parameters of the binary sub-systems, Fe-B, Fe-Cr and B-Cr, are taken from earlier assessments slightly modifying the Fe-B and B-Cr descriptions, and those of the ternary system are optimized in this study using experimental thermodynamic and phase equilibrium data from the literature. The solution phases are described using substitutional solution model. The borides are treated as stoichiometric or semi-stoichiometric phases and described with two-sublattice models.
Tribological Properties of Copper-Based Composites with Lubricating Phase Particles
Authors: Juszczyk B. , Kulasa J. , Malara S. , Czepelak M. , Malec W. , Cwolek B. , Wierzbicki Ł.
Published: June 2014

The results of research into influence of chemical composition on structure and tribological properties of copper-based composites intended for slide bearings are presented in this paper. The study was focused on copper alloys with lubricating phase particles in form of graphite, tungsten disulphide (WS2), molybdenum disulphide (MoS2) and glassy carbon. The metallic matrix of composite materials was composed of alloys from Cu-Sn-Zn system. The mass content of lubricating phase particles was from 5 to 20%. The process of production of subject materials included the processes conducted with full or partial contribution of liquid phase and it was conducted by two methods. Both the method of classic powder metallurgy and stir casting method were used for the production of composites. Lubricating phase particles heated to the temperature of 200°C were introduced to liquid metal bath and then the process of stirring and casting to moulds was performed. In case of production of composites by powder metallurgy, the process included mixing of bronze powders and lubricating phase particles, and then their consolidation. Sintering process was conducted in temperature between 750-800°C. The produced materials were tested in terms of microstructure and tribological properties with the CSM Instruments tribometer.
Root Canal System Analysis with a Group of First Permanent Molars of Upper and Lower Jaw
Authors: Mroczek K. , Szlązak K. , Jodkowska E. , Jaroszewicz J. , Swięszkowski W. , Kurzydłowski K.J.
Published: June 2014

A progressive bacteria invasion on tooth tissues leads to pulp inflammation, microabscesses of the pulp, destruction and in consequence inflammation of periapical tissues. Therefore the aim of endodontic treatment is three dimensional debridement of a root canal from the vent in pulp chamber to the physiological narrowing. Therefore the aim of the study is analysis of root canal configuration, number of canals, presence of lateral canals and canal delta with the group of first permanent molars. At the same time the accuracy of the radiological examination (x-ray images) is estimated due to comprehension of X-ray images performed before teeth preparation with root canal system and after observation of transversal cuts by means of light microscopy and microtomography. This establishment is presented through the differences in conventional radiological image and clinical assessment.
Technology of Repairing QE22 Alloy Casts
Authors: Turowska A. , Adamiec J. , Rzychoń T.
Published: June 2014

Hot cracking is one of the main problems involved in the casting of magnesium alloys and their joining by means of welding. Despite many research done, this type of cracking still constitutes a major problem in industrial practice. The present paper describes the impact of metallurgical, structural and technological factors on the susceptibility of the QE22 alloy to hot cracking of the repaired joints. A technology of repairing the QE22 alloy casts by means of welding and pad welding, was developed. The technology meets the qualification requirements according to EN 15614-4.
The Analysis of the Mechanical Properties of High Carbon Steel Wires after Multipass High Speed Drawning Process in Conventional and Hydrodynamic Dies
Authors: Suliga M.
Published: June 2014

In this work the influence of the drawing speed on lubrication conditions and mechanical properties of high carbon steel wires drawn in conventional and hydrodynamic dies has been assessed. The drawing process of ϕ5.5 mm wires to the final wire of ϕ1.7 mm was conducted in 12 passes, in industrial conditions, by means of a modern Koch multi-die drawing machine. The drawing speeds in the last passes were: 5, 10, 15, 20 and 25 m/s. For final wires ϕ1.7 mm the investigation of mechanical properties has been carried out, in which yield strength, tensile strength, uniform and total elongation and also number of twists were determined. It has been shown that the increase of drawing speed from 5 m/s up to 25 m/s caused the increase by 6% strength properties and decrease of plasticity properties by 10%. Higher values of tensile strength and yield strength of the wires drawn conventionally with high speeds are associated with worse conditions, while in case of wires drawn hydrodynamically the main factor which caused the increase of strength properties was high lubricant pressure in hydrodynamic die, which caused the increase of total draft.
Possibilities of 3D Model Application in the Process of Aluminium Refining in the Unit With Rotary Impeller
Authors: Merder T. , Saternus M. , Warzecha P.
Published: June 2014

Both primary and secondary aluminium have to be refined, especially by barbotage process. To know better the mechanism of blowing argon through aluminium in reactors with rotary impellers, numerical modelling is applied. It allows to obtain useful information like: the level of velocity field or participation of gaseous phase. However, numerical analysis requires choosing the proper model which would describe the physical phenomena occurring in the process. So, AnsysFluent code was used in the research. It allows to calculate the two-phase liquid flow for the 2D and 3D co-ordinate systems. Results of calculations for the 3D case can describe more accurately the spatial picture of the movement trajectory of the blown gas bubbles. Calculations were done for the flow rate of refining gas equal 5 dm3/min and for two cases: when there was no rotation and with 300 rpm rotary impeller speed.
Influence of the Bed Type on the Flow Resistance Change During the Two-Phase (Gas + Powder) Flow through the Descending Packed Bed
Authors: Panic B.
Published: June 2014

The flow of gases with powder in the countercurrent to the charge materials occurs in many chemical processes. In the shaft metallurgical devices, the physical and chemical processes take place also in the countercurrent system. An important issue is that there are no disruptions of the flow in this multiphase system. Under real operating conditions of the device, the powder is generated within the process and its source is the charge or it is inserted to the device within the process procedure.

In this system, a problem of bed particle suspension appears. That is why the author undertook investigations on the gas - powder flow in the descending bed. A physical model of this system was constructed. The experiments were performed and the influence of gas velocity, a type and size of the bed and powder particles as well as the powder concentration in the gas was established. Conditions when the descending bed suspension occurs were defined. In the case of physical model with glass materials, the suspension of bed did not occur. Therefore, investigations using beds of high alumina materials, blast furnace pellets and iron powder were performed. The results are presented below. When the bed of glass spheres was replaced with the bed of alumina spheres, a considerable increase in the volume of powder held up in the bed the gas flow resistance were observed. The surface properties of bed particles changed and better conditions for powder holdup were created. The actual gas velocity in the bed increased due to void fraction reduction.

Replacement of the glass powder with the iron powder caused a change in the powder density, its surface properties and the shape factor. Greater amounts of the iron powder were held up in the bed and the gas flow resistance increased.

Comparing the alumina particle bed - iron powder system to the blast furnace pellet bed - iron powder system, changes in the surface properties of bed particles and the void fraction of bed changed. The study results were the basis for defining conditions of the descending bed suspension.
The Dynamic Characteristics Research of Compact Heat Regenerator used in Regenerative Burners for Metallurgical Heating Furnaces
Authors: Wnęk M.
Published: June 2014

The gas burner is a device which the main aim is delivering the right number of gas fuel and oxidizing agent and it also has to ensure flame stabilization. The difficult controlling problem appears when the modern and compact high temperature regenerative burners are used. The controlling difficulties in those systems are related to the large number of burners and a periodic change (with high frequency) of temperature field which depends on such parameter as reversion time. The knowledge of the dynamic and static regenerator characteristics makes easier the programming of automatic control and regulation process and helps in creating the new regenerator filling construction in order to improve the heat transfer intensification and the furnaces efficiency. Based on research results the paper presents the selected data research dealing with the dynamic and static regenerator characteristic. The measurement of quick-changing fluctuating thermal field and the way of the temperature sensors selection have been indicated. The regenerator starting state and pseudo-steady state characteristics have also been presented. Finally the qualities of the regenerator and the economic income have been expressed.
Biomass as a Source of Energy in Iron Ore Agglomerate Production Process
Authors: Fröhlichová M. , Legemza J. , Findorák R. , Mašlejová A.
Published: June 2014

This article contains characteristics of selected types of biomass, which can be considered as an alternative fuel in the production of iron ore agglomerate.

Selected types of biomass were evaluated by chemical analysis, X-ray phase analysis and microscopic analysis using the camera on microscope Olympus BX 51. Biomass was characterized according to its structure, chemical composition and chemical composition of ash. The obtained data were confronted with the data for coke breeze and based on the results, conclusions were made about the possible use of selected types of biomass as an alternative fuel in the process of iron ore agglomerate production.
Microstructure Evolution and Mechanical Properties of C-Mn Cold Rolled Dual Phase Steel after Continuous Annealing Process in Laboratory Conditions
Authors: Šebek M. , Horňak P. , Zimovčák P. , Longauer S.
Published: June 2014

The article deals with the influence of annealing parameters on evolution of microstructure and mechanical properties of dual phase steel. Dual phase steel was annealed in laboratory conditions according to the three chosen cycles of annealing: into intercritical region (780°C), into austenite region (920°C) and into austenite region (920°C) by subsequently cooling into intercritical region (780°C) with the hold at the temperature of 495°C. Simulation of annealing regimes by thermo-mechanical simulator Gleeble was done. The obtained microstructure consists from three phases: ferritic matrix, martensite and martensite/ bainite grains. For the microstructure identification the TEM and nanoindentation experiments were performed.
Effects of Pressure on the Rate of Tin Evaporation From Liquid Iron
Authors: Lipart J. , Łabaj J. , Słowikowski M. , Jama D.
Published: June 2014

In the paper, tin elimination from liquid iron alloy via low-pressure evaporation has been analysed. The experiments were performed using a single-chamber VIM 20-50 vacuum induction furnace at 1923 K and the operating pressure of 0.05 to 557 Pa.
Time Trend and prediction of Grade 2 Disability among new cases of leprosy in Nepal: A Statistical Modelling
Authors: Sathian Brijesh , Kumar Ajay , Sreedharan Jayadevan , Banerjee Indrajit , Roy Bedanta , Rajesh E
Published: June 2014

Background  It is estimated that globally there are around 2 million people with grade 2 disabilities attributed to leprosy. Objective of the study was to find out the time trends of Grade 2 Disability among the new cases of Leprosy in Nepal. Materials and Methods A retrospective study was carried out on the data collected from the Health ministry records of Nepal, between 2009 and 2013. The annual reported numbers of Grade 2 Disability among new cases of leprosy plotted in y-axis against the corresponding year in the x-axis. Curve fitting, also known as regression analysis, was used to find the "best fit" line or curve for a series of data points. Linear, Logarithmic, Inverse, Quadratic, and Cubic were chosen to fit to the obtained curve. Descriptive statistics and statistical modelling were used for the analysis and forecasting of data. Results Including the constant term from the equation, the inverse model was the best fit, for the forecasting of the Grade 2 Disability among new cases of leprosy in Nepal [R2=0.739, p=0.062]. Using inverse model, it is estimated that 78 with CI [0, 170] of Grade 2 Disability among new cases of leprosy can be expected in Nepal by the year 2020. Conclusion Our study proves Inverse model is the best fit for epidemiological modelling of Grade 2 Disability among the new cases of Leprosy in Nepal. Prevention of disabilities should begin with diagnosing leprosy.DOI: http://dx.doi.org/10.3126/nje.v4i3.10668 Nepal Journal of Epidemiology 2014; 4(3): 378-383
Novel Embossing System for Replicating Micro-Structures on Curved Surfaces
Authors: Nian S.-C.
Published: June 2014

Hot embossing is widely used to replicate micro-structures on polymer plate surfaces. The polymer parts of curved surfaces with micro-structures have important functions in various optoelectronic components. However, due to the high precision needed for embossing machines and mold manufacturing, achieving uniform pressure on curved surfaces during the embossing process is difficult. This study modified conventional hot embossing processes to develop an elastic bag embossing system (EBES) for replicating micro-structures on curved surfaces. The pressure equalizing properties of the elastic bag enabled uniform application of pressure on curved surfaces embossed with a general hot compression machine. For the EBES-assisted hot embossing process, a nickel stamper was attached to the elastic bag to compress and replicate micro-structures on the PC film covering the mold surface with single direction curve. This study also developed an EBES-assisted UV exposure process that used a PDMS soft-mold attached to the elastic bag surface to compress the UV curable photoresist covering the surface of the convex lens. Micro-structures were then formed by exposing the photoresist. Experimental results showed that the EBES with Ni stamper could successfully replicated micro-structures onto a 200 mm × 200 mm curved PC film and that the EBES-assisted UV exposure could successfully produced a 50 mm diameter fresnel lens on a convex profile with material of UV photoresist. Experimental tests of pressure-sensitive film showed that EBES enables uniform application of pressure on curved surfaces during the embossing process on standard hot compression machines. The experimental results confirm that the EBES developed in this study is an efficient and economical method for replicating micro-structures on curved surface.
Enhance Slower Relaxation Process of Poly(ethyl acrylate) through Internal Plasticization
Authors: He X. R. , Yu H. , Zhang R. , Yang C. H.
Published: June 2014

In this paper, we report a chemical way to resolve longer motions units in the glass-rubber transition region of poly (ethyl acrylate) (PEA), so called internal plasticization. The ethyl acrylate (EA) monomers were copolymerized with little amount of isoprene (IP) monomers. We propose that the single bonds adjunct to double bonds would have better flexible activity than usual single bonds, so the motion units located between two adjunct double bonds would be enhanced. The dynamic mechanical spectra of internally plasticized PEA (IPPEA) and PEA show that the tan δ of IPPEA is asymmetric, while the tan δ of PEA is symmetric. Furthermore, the results of 2D-DMAS show that the LSM, SRM and RM of IPPEA are located at 7 °C, 12 °C and 36 °C. The shoulder peak of tan δ of IPPEA at higher temperature side was confirmed that it contains sub-rouse mode (SRM) and rouse mode (RM). Thus, internal plasticization is an effective way to resolve modes above Tg.
Public Attitudes toward Animal Research: A Review
Authors: Ormandy Elisabeth , Schuppli Catherine
Published: June 2014

The exploration of public attitudes toward animal research is important given recent developments in animal research (e.g., increasing creation and use of genetically modified animals, and plans for progress in areas such as personalized medicine), and the shifting relationship between science and society (i.e., a move toward the democratization of science). As such, public engagement on issues related to animal research, including exploration of public attitudes, provides a means of achieving socially acceptable scientific practice and oversight through an understanding of societal values and concerns. Numerous studies have been conducted to explore public attitudes toward animal use, and more specifically the use of animals in research. This paper reviews relevant literature using three categories of influential factors: personal and cultural characteristics, animal characteristics, and research characteristics. A critique is given of survey style methods used to collect data on public attitudes, and recommendations are given on how best to address current gaps in public attitudes literature.
Simulation of Entropy Generation under Stall Conditions in a Centrifugal Fan
Authors: Zhang Lei , Lang Jinhua , Jiang Kuan , Wang Songling
Published: June 2014

Rotating stalls are generally the first instability met in turbomachinery, before surges. This 3D phenomenon is characterized by one or more stalled flow cells which rotate at a fraction of the impeller speed. The goal of the present work is to shed some light on the entropy generation in a centrifugal fan under rotating stall conditions. A numerical simulation of entropy generation is carried out with the ANSYS Fluent software which solves the Navier-Stokes equations and user defined function (UDF). The entropy generation characteristics in the centrifugal fan for five typical conditions are presented and discussed, involving the design condition, conditions on occurrence and development of stall inception, the rotating stall conditions with two throttle coefficients. The results show that the entropy generation increases after the occurrence of stall inception. The high entropy generation areas move along the circumferential and axial directions, and finally merge into one stall cell. The entropy generation rate during circumferential propagation of the stall cell is also discussed, showing that the entropy generation history is similar to sine curves in impeller and volute, and the volute tongue has a great influence on entropy generation in the centrifugal fan.
Entropy Evolution and Uncertainty Estimation with Dynamical Systems
Authors: Liang X.
Published: June 2014

This paper presents a comprehensive introduction and systematic derivation of the evolutionary equations for absolute entropy H and relative entropy D, some of which exist sporadically in the literature in different forms under different subjects, within the framework of dynamical systems. In general, both H and D are dissipated, and the dissipation bears a form reminiscent of the Fisher information; in the absence of stochasticity, dH/dt is connected to the rate of phase space expansion, and D stays invariant, i.e., the separation of two probability density functions is always conserved. These formulas are validated with linear systems, and put to application with the Lorenz system and a large-dimensional stochastic quasi-geostrophic flow problem. In the Lorenz case, H falls at a constant rate with time, implying that H will eventually become negative, a situation beyond the capability of the commonly used computational technique like coarse-graining and bin counting. For the stochastic flow problem, it is first reduced to a computationally tractable low-dimensional system, using a reduced model approach, and then handled through ensemble prediction. Both the Lorenz system and the stochastic flow system are examples of self-organization in the light of uncertainty reduction. The latter particularly shows that, sometimes stochasticity may actually enhance the self-organization process.
Effect of Aqueous Ammonia Soaking on the Methane Yield and Composition of Digested Manure Fibers Applying Different Ammonia Concentrations and Treatment Durations
Authors: Mirtsou-Xanthopoulou Chrysoula , Jurado Esperanza , Skiadas Ioannis , Gavala Hariklia
Published: June 2014

The continuously increasing demand for renewable energy sources renders anaerobic digestion one of the most promising technologies for renewable energy production. Due to the animal production intensification, manure is being used as the primary feedstock for most biogas plants. Thus, their economical profitable operation relies on increasing the methane yield from manure, and especially of its solid fraction which is not so easily degradable. In the present study, aqueous ammonia soaking (AAS) at six different concentrations in ammonia (5%, 10%, 15%, 20%, 25% and 32%) and for 1, 3 and 5 days at 22 °C was applied on digested fibers separated from the effluent of a manure-fed, full-scale anaerobic digester. A methane yield increase from 76% to 104% was achieved during the first series of experiments, while the difference in reagent concentration did not considerably affect the methane yield. It was shown that the optimal duration was three days for both 5% and 25% w/w reagent concentrations in ammonia tested. Carbohydrates and phosphorus content remained unaffected, while a slight decrease in Klason lignin and non-soluble organic nitrogen content was observed after AAS. It is concluded that AAS is a very promising treatment resulting to an overall increase of the methane yield of digested manure fibers from 76% to 265% depending on the conditions and the batch of digested fibers used (an even higher increase of 190%–265% was achieved during the 2nd series of experiments, where different AAS durations were tested, compared to the 1st series were different ammonia concentrations were applied).
Characterization of the Zebrafish Homolog of Zipper Interacting Protein Kinase
Authors: Carr Brandon , Basepayne Tamara , Chen Lawrence , Jayashankar Vaishali , Weiser Douglas
Published: June 2014

Zipper-interacting protein kinase (ZIPK) is a conserved vertebrate-specific regulator of actomyosin contractility in smooth muscle and non-muscle cells. Murine ZIPK has undergone an unusual divergence in sequence and regulation compared to other ZIPK orthologs. In humans, subcellular localization is controlled by phosphorylation of threonines 299 and 300. In contrast, ZIPK subcellular localization in mouse and rat is controlled by interaction with PAR-4. We carried out a comparative biochemical characterization of the regulation of the zebrafish ortholog of ZIPK. Like the human orthologs zebrafish ZIPK undergoes nucleocytoplasmic-shuttling and is abundant in the cytoplasm, unlike the primarily nuclear rat ZIPK. Rat ZIPK, but not human or zebrafish ZIPK, interacts with zebrafish PAR-4. Mutation of the conserved residues required for activation of the mammalian orthologs abrogated activity of the zebrafish ZIPK. In contrast to the human ortholog, mutation of threonine 299 and 300 in the zebrafish ZIPK has no effect on the activity or subcellular localization. Thus, we found that zebrafish ZIPK functions in a manner most similar to the human ZIPK and quite distinct from murine orthologs, yet the regulation of subcellular localization is not conserved.