bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of Aldosterone and Cortisol Production by the Transcriptional Repressor Neuron Restrictive Silencer Factor
Authors: Somekawa Satoshi , Imagawa Keiichi , Naya Noriyuki , Takemoto Yasuhiro , Onoue Kenji , Okayama Satoshi , Takeda Yukiji , Kawata Hiroyuki , Horii Manabu , Nakajima Tamio , Uemura Shiro , Mochizuki Naoki , Saito Yoshihiko
Published: April 2009

Aldosterone synthase (CYP11B2) and 11β-hydroxylase (CYP11B1) regulate aldosterone and cortisol production, respectively. The expression of these enzymes is promoted by calcium influx through Cav3.2, a T-type calcium channel. Neuron-restrictive silencer factor (NRSF) binds to neuron-restrictive silencer element (NRSE) to suppress the transcription of NRSE-containing genes. We found a NRSE-like sequence in human CYP11B2 and CYP11B1 genes as well as the CACNA1H gene of many mammalian species. The CACNA1H gene encodes the α-subunit of Cav3.2. Here we investigated how NRSF/NRSE regulates aldosterone and cortisol synthesis. Inhibition of endogenous NRSF by an adenovirus-expressing dominant-negative NRSF (AD/dnNRSF) increased human CYP11B2 and CYP11B1 mRNA expression, leading to aldosterone and cortisol secretion in human adrenocortical (H295R) cells. In reporter gene experiments, NRSE suppressed luciferase reporters driven by CYP11B2 and CYP11B1 promoters and dnNRSF enhanced them. Moreover, cotransfection of dnNRSF increased luciferase activity of reporter genes after deletion or mutation of NRSE, suggesting that NRSF/NRSE regulates transcription of CYP11B2 and CYP11B1 genes indirectly. AD/dnNRSF augmented mRNA expression of rat CYP11B2 and CYP11B1 genes, neither of which contains a NRSE-like sequence in rat adrenal cells. AD/dnNRSE also significantly increased CACNA1H mRNA in H295R and rat adrenal cells. Efonidipine, a T/L-type calcium channel blocker, significantly suppressed dnNRSF-mediated up-regulation of CYP11B2 and CYP11B1 expression. Moreover, NRSF/NRSE is also involved in angiotensin II- and K+-stimulated augmentation of CYP11B2 and CYP11B1 gene transcription. In conclusion, NRSF/NRSE controls aldosterone and cortisol synthesis by regulating CYP11B2 and CYP11B1 gene transcription mainly through NRSF/NRSE-mediated enhancement of the CACNA1H gene.
Androgen Receptor Roles in Spermatogenesis and Fertility: Lessons from Testicular Cell-Specific Androgen Receptor Knockout Mice
Authors: Wang Ruey-Sheng , Yeh Shuyuan , Tzeng Chii-Ruey , Chang Chawnshang
Published: April 2009

Androgens are critical steroid hormones that determine the expression of the male phenotype, including the outward development of secondary sex characteristics as well as the initiation and maintenance of spermatogenesis. Their actions are mediated by the androgen receptor (AR), a member of the nuclear receptor superfamily. AR functions as a ligand-dependent transcription factor, regulating expression of an array of androgen-responsive genes. Androgen and the AR play important roles in male spermatogenesis and fertility. The recent generation and characterization of male total and conditional AR knockout mice from different laboratories demonstrated the necessity of AR signaling for both external and internal male phenotype development. As expected, the male total AR knockout mice exhibited female-typical external appearance (including a vagina with a blind end and a clitoris-like phallus), the testis was located abdominally, and germ cell development was severely disrupted, which was similar to a human complete androgen insensitivity syndrome or testicular feminization mouse. However, the process of spermatogenesis is highly dependent on autocrine and paracrine communication among testicular cell types, and the disruption of AR throughout an experimental animal cannot answer the question about how AR in each type of testicular cell can play roles in the process of spermatogenesis. In this review, we provide new insights by comparing the results of cell-specific AR knockout in germ cells, peritubular myoid cells, Leydig cells, and Sertoli cells mouse models that were generated by different laboratories to see the consequent defects in spermatogenesis due to AR loss in different testicular cell types in spermatogenesis. Briefly, this review summarizes these results as follows: 1) the impact of lacking AR in Sertoli cells mainly affects Sertoli cell functions to support and nurture germ cells, leading to spermatogenesis arrest at the diplotene primary spermatocyte stage prior to the accomplishment of first meiotic division; 2) the impact of lacking AR in Leydig cells mainly affects steroidogenic functions leading to arrest of spermatogenesis at the round spermatid stage; 3) the impact of lacking AR in the smooth muscle cells and peritubular myoid cells in mice results in similar fertility despite decreased sperm output as compared to wild-type controls; and 4) the deletion of AR gene in mouse germ cells does not affect spermatogenesis and male fertility. This review tries to clarify the useful information regarding how androgen/AR functions in individual cells of the testis. The future studies of detailed molecular mechanisms in these in vivo animals with cell-specific AR knockout could possibly lead to useful insights for improvements in the treatment of male infertility, hypogonadism, and testicular dysgenesis syndrome, and in attempts to create safe as well as effective male contraceptive methods.
Memory in Times of War
Authors: Uribe María Victoria
Published: April 2009

This article describes the complexity of transitional justice in Colombia since the approval of Law 975, known as the “Justice and Peace Law,” and the demobilization of the United Autodefenses of Colombia in 2005. In the middle of the open war between the Revolutionary Armed Forces of Colombia and the Colombian government, different victims' organizations have empowered themselves around their struggle to reconstruct memory.
Self-Appreciation; or, The Aspirations of Human Capital
Authors: Feher Michel
Published: April 2009

Human capital is to neoliberalism what Marx's free worker was to liberal capitalism, that is, the subjective formation at once presupposed and targeted by neoliberal technologies of government. According to this thesis, the neoliberal condition involves investors in their own human capital who, as such, seek to appreciate the value of the portfolio of conducts that constitutes them and whose relationship to themselves is speculative rather than possessive—as was the case of their liberal predecessors.
Imaging Tibet
Authors: Mehla
Published: April 2009

This collection of images documents aspects of a Tibetan nomadic family's everyday life. The photographs capture members of the photographer's family in their summer pastures, near Rega Village, Sichuan Province, People's Republic of China.
Untimely Vision: Aimé Césaire, Decolonization, Utopia
Authors: Wilder Gary
Published: April 2009

This essay focuses on Aimé Césaire's post–World War II commitment to colonial emancipation without national independence. It examines how his constitutional initiatives to enact a future with France in an age of decolonization may be read as politically untimely and strategic utopian engagements with the complex problem of freedom. It suggests that they can be grasped as such only if we recognize that Césaire's 1946 program to transform Antillean colonies into French departments and his subsequent attempt to reconstitute France as a federal republic were mediated by the spirits of Toussaint Louverture and Victor Schoelcher and the legacies of the 1790s revolution in Saint-Domingue and the 1848 abolition of slavery. At these crucial turning points, imperial conditions had created the possibility of nonnational colonial emancipation even as certain kinds of instituted liberty themselves obstructed the prospect of substantive freedom. For subsequent generations, such failed initiatives then became futures past that condensed not yet realized but ever-available emancipatory potentialities.
Experimental study of high-strength low-alloy sheet metal components with holes on the bending surfaces
Authors: Farsi M A , Arezoo B
Published: April 2009

Bending is one of the processes frequently used in the manufacture of sheet metal components. Springback is an important issue in bending operations since it controls the final shape of the parts. Hence, exact estimation of its value is essential for die design operations. In industry, the springback is usually obtained from empirical equations or mostly from handbook tables. These equations or tables are mainly suitable for components that have no holes on the bending surfaces, and they cannot be used for parts with any holes on the bending surfaces. In the present work, the influence of holes and their sizes on the bending surfaces of the high-strength low-alloy (HSLA) sheet metal steel using V-shape dies is studied. Different die angles, die widths, and sheet metal thicknesses are used in the experiments. The results show that all these parameters have an effect on the springback and the bending force, but their effects are not similar. An equation is derived for determining the bending forces for parts with holes on the bending surfaces.
Mathematical models for manufacturing using Vudjood algebra
Authors: Mirahmadi A
Published: April 2009

Vudjood algebra is a mathematical method that describes a domain or region, which can be used for designing manufacturing software. The most important application of Vudjood algebra is the creation of models for computer-aided design and computer integrated manufacturing. Here, Vudjood algebra becomes a tool for the software developer. The application of visual artificial intelligence in manufacturing will be the next developmental step in production technology. Operators in this field will be universal humanoid robots that can visually recognize surrounding objects and machines. These robots will work with mathematical models of the surrounding objects and machines. This paper explains how Vudjood algebra can accelerate the development of autonomic-acting machines and provide a tool for shape manufacturing.
Evaluation of the measurement of metal flow and strain distribution in bulk metal forming
Authors: Li F , Lin J F , Liu X J , Li C
Published: April 2009

A measuring method, using rings of screw threads is proposed in order to solve the difficulties associated with measuring the strain and flow distributions during die forging processes. This method does not use a substitute material to measure the magnitude of the three-dimensional plastic deformation and it can therefore be used in quantitative analysis. Using the proposed method, the strain and four flow lines of typical sections were measured and analysed during the deformation of a coupled model. A distribution rule for the stress—strain relationship is presented. The proposed method is shown to be able to measure and analyse the metal flow during die forging. It can be used to study material flow and to predict strain distribution in general bulk metal forming processes such as extrusion.
Analysis of parametric stability for a spur gear pair system considering the effect of extended tooth contact
Authors: Han Q , Wang J , Li Q
Published: April 2009

In spur gear dynamic analysis, rectangular waves are often used to approximate the mesh stiffness alternating between one and two pairs of teeth in contact. But in actual practice, extended tooth contact (ETC) occurs due to gear tooth deflection under load. Considering the effect of ETC, the mesh stiffness in the pre-mature and post-mature contact regions is gradually rather than abruptly varying with time, which would influence the parametric stability of the geared system significantly. Therefore, research on parametric stability for a spur gear pair system considering the effect of ETC is carried out in this article. First, a torsional parametric vibration model for a spur gear pair system is established and the periodically time-varying mesh stiffness is approximated linearly by trapezoidal waveforms (with the effect of ETC) and rectangular waves (without the effect of ETC). Then, the Floquet theory for stability analysis (including two key elements: one is the derivation of state transition matrix (STM); the other is the stability criterion for parametric vibration system) is presented briefly. Based on these, the stabilities (stable and unstable regions) of a practically used high-speed and heavy-load spur gear pair with and without taking into account ETC are determined utilizing Floquet theory, respectively, and the differences between the two cases in three ranges of operating speeds for the system (low speed range, middle speed range, and high speed range) are contrasted in detail. In addition, various values of operating torques and mesh damping of the gear pair are also simulated and discussed for their influences upon unstable regions.
An investigation of the tertiary coupling effect under the longitudinal mode of a piezoelectric crystal
Authors: Zhang Z H , Sun B Y , Qian M , Zhang J , Shi Y H , Zhou X
Published: April 2009

In this article, multiple piezoelectric effects are investigated on the basis of the classical piezoelectric theory. The objective reality of multiple piezoelectric effects is elucidated from theoretical analysis first. Based on four kinds of piezoelectric equations, the relationship between the generation of multiple piezoelectric effects and boundary conditions is analysed, the process of their generation is elaborated, and the formulae of the tertiary piezoelectric effect are deduced. Then, the experimental results of the tertiary coupling effect are obtained under the longitudinal mode of a PZT-5 stack by the methods that are equivalent to changing boundary conditions. Experimental data show that the output of the tertiary direct and converse piezoelectric effect is also linear with the applied force and voltage, respectively. However, the output directions are opposite to that of the primary piezoelectric effect. The theoretical analysis is justified by experimental results and the experimental methods presented are proved to be scientific and feasible. Moreover, the influence of the tertiary piezoelectric effect on the piezoelectric coefficient and the performance of sensors and actuators is further analysed. The study of multiple piezoelectric effects provides a new method for the improvement of the performance of piezoelectric sensors and actuators.
On the performance of a cascade of improved turbine nozzle blades in nucleating steam. Part 1: Surface pressure distributions
Authors: Bakhtar F , Mamat Z A , Jadayel O C , Mahpeykar M R
Published: April 2009

This article is the first of a set and describes the results of surface pressure measurements and flow visualizations in a cascade of improved steam turbine nozzle blade profiles. In the course of expansion of steam in turbines, the state path crosses the saturation line and the fluid nucleates to become a two-phase mixture. Formation and subsequent behaviour of the liquid lowers the performance of turbine wet stages. Turbine two-phase flow conditions can be reproduced satisfactorily under blow-down conditions for systematic study. Following earlier studies of some typical profiles the performance of a new design of blades is presented. A substantially improved aerodynamic performance has been achieved by the new profile.
Identification of dynamic phenomena in pipes supplied with a pulsating flow of gas
Authors: Olczyk A
Published: April 2009

Pulsating flow is typical of displacement machines such as piston engines, compressors, or other displacement devices. The cyclic movement of the working element (piston, valve, membrane, etc.) generates pulsations, which, from a dynamic point of view, can be considered as excitation in the system composed of a flowing gas and pipes in which the flow takes place.

This study shows that under certain conditions, a significant increase of pulse amplitudes occurs and transient values of main flow parameters are up to a few times higher than that for the equivalent steady flow conditions. This unsteadiness can be harmful or even damaging; however, in some cases it can be profitable (e.g. induction ramming of combustion engines). In order to investigate which conditions are favourable to obtain such effects in pipes, four different systems, distinguished by a different level of choking at the pipe outlet section, were tested.

The experimental tests performed in the range of excitation frequencies of 0—200 Hz have shown that systems with low choking at the pipe outlet are more prone to strong dynamic effects, characterized by considerable growth of pulse amplitudes and an intensive reverse flow occurring in the proximity of resonance frequencies.

In systems with high choking at the pipe outlet section, those effects were very weak.

Characteristic frequencies, for which the resonance takes place, depend on the pipe length and can be determined theoretically with a simple acoustic model or a one-dimensional model ‘ x— t’ describing a pulsating flow in the pipe. The experimental verification of those resonance frequencies can be conducted with the use of transient flow parameters recorded by appropriate fast response sensors.
Nano-positioning using an adaptive pulse width approach
Authors: Zelenika S , De Bona F
Published: April 2009

Macro- and micro-dynamic mechanical non-linearities limiting the precision of conventional DC motor-driven positioning systems based on sliding and rolling elements have been characterized experimentally via a laser interferometric system. The obtained results confirm recent tribological models. In particular, the parameters describing the non-linear elastic and plastic phenomena related to pre-sliding displacement have been identified and used to develop an integrated system model. It was therefore possible to prove that, in the range of displacements corresponding to the pre-sliding phase, there is a quadratic dependence between the duration of an actuating impulsive force and the resulting displacement. According to a pulse width scheme, a control law has been implemented whose adaptive structure compensates for the position and time variability of the observed non-linear effects. The application of the proposed approach to both short and long travel ranges and the reached nanometric accuracies confirm the applicability of the proposed control scheme to compensate concurrently the macro- and the micro-dynamic effects.
Do Smoking Cessation Activities as Part of Oral Health Promotion Vary between Dental Care Providers Relative to the NHS/Private Treatment Mix Offered? A Study in West Yorkshire
Authors: Csikar Julia , Williams Sonia A , Beal John
Published: April 2009

Objective

To determine whether or not and to what extent health promotion and smoking cessation activities varied between dental practices relative to their National Health Service (NHS)/private treatment mix.

Methods

A piloted questionnaire was posted to all dental practitioners within West Yorkshire, with two follow-up mailings.

Results

The response rate was 50% (386/769) of dental practitioners within West Yorkshire. Respondents were dichotomised at the median according to the proportion of NHS/private patients seen (>89% NHS, described as ‘NHS-orientated practices’ [NHSOPs] and <90% NHS, referred to as ‘more privately-orientated practices’ [POPs]). Practice profiles: Compared with POPs, NHSOPs’ respondents had a significantly higher proportion of adult patients exempt from NHS charges (34% vs 57%), together with a higher proportion of children. Health promotion activities: there was no significant difference between the two groups of practitioners regarding the proportion claiming to give smoking cessation advice (42% vs 37%), although a higher proportion of those from POPs offered guidance on diet and nutrition (67% vs 54%; P<0.05). However, a significantly higher proportion of POP respondents reported (a) recording smoking status in the clinical notes, (b) giving out smoking-related leaflets, and (c) referring to an NHS ‘Stop Smoking Service’. NHSOP respondents were more likely to cite ‘lack of time’, ‘no incentive’ and ‘lack of expertise’ as potential barriers to providing health promotion advice. General: 7% of POP respondents thought that the new NHS contract arrangements would influence their smoking cessation activities versus 19% of NHSOP residents.

Conclusions

Considerable variation between NHSOPs and POPs was found when comparing aspects of their health promotion/smoking cessation activities. The findings identified here suggest that the current situation, with regard to the NHS, will tend to increase health inequalities.
The Prevalence of Orofacial Pain and Tooth Fracture (Odontocrexis) Associated with SCUBA Diving
Authors: Jagger Robert G , Shah Chand A , Weerapperuma Indika D , Jagger Daryll C
Published: April 2009

Aim

To assess the prevalence of orofacial complications associated with SCUBA (self-contained underwater breathing apparatus) diving. Main outcome measures were prevalence of orofacial pain and odontocrexis.

Method

Two hundred divers at four dive centres on the north-east coast of Australia were asked to complete a questionnaire that requested information regarding diving experience and facial pain and dental symptoms experienced during diving.

Results

One hundred and twenty-five completed questionnaires were returned (63% response rate). The prevalence of reported orofacial pain was 44%. Twenty-one per cent reported toothache, 27% sinus pain, 16% jaw pain, and 12% other pain. The prevalence of odontocrexis was less than 1%. Less than 1% had lost a filling when diving. No divers reported a crown or bridge being dislodged during diving.

Conclusion

Among those who returned questionnaires, orofacial pain in divers was common and odontocrexis was rare.
Metacognitive monitoring and control processes involved in primary school children's test performance
Authors: Roebers Claudia M. , Schmid Corinne , Roderer Thomas
Published: April 2009

Background Within the context of students' self‐regulated learning, the interplay between learners' individual characteristics and the context of testing have been emphasized for assessing learning outcomes.

Aims The present study examined metacognitive monitoring and control processes in elementary schoolchildren's test taking behaviour and explored the impacts of these metacognitive skills for the accuracy and the quantity of test performance.

Sample and methods A total of 133 participants from third and fifth grade did a cloze test about a previously learned science topic, gave confidence judgments for every answer, and were then allowed to cross‐out answers if they wished. Two different mock scoring schemes for test performance were compared with a control group.

Results Results revealed well‐developed monitoring skills indicating that by the age of 9 children can reliably distinguish between correct and incorrect answers. As for control skills, 11‐ and 12‐year‐olds proved to be better able to improve their test performance by selectively withdrawing answers that would have been incorrect than the 9‐ to 10‐year‐olds.

Conclusions The study offers evidence for the impact of metacognitive processes in students' learning outcomes and documents strategic behaviour during test taking, as well as developmental progression in the involved skills.
Integrated Reservoir Characterization and Performance Prediction: A Case Study of a West Texas Carbonate-Classic Reservoir
Authors: Ross J. Mike , Mansoori John , Chambers Rich
Published: April 2009

The objectives were to perform a field study to:

Evaluate geostatistical techniques to integrate data. Compare reservoir descriptions with and without crosswell tomography data integrated. Determine if reservoir descriptions constrained by synthetic crosswell tomography data reduce uncertainty, compared to reservoir descriptions not constrained by synthetic tomography data. (i.e., Can the uncertainty in reservoir performance be reduced measurably if cross well tomography is acquired and used as additional data to constrain geostatistical reservoir descriptions?) Compare geostatistical to conventional reservoir descriptions. Assess uncertainty of reservoir performance (cumulative oil production, oil production rate, and water-oil ratio) for primary, secondary and tertiary production.
Dispersive liquid-liquid microextraction and liquid chromatographic determination of pentachlorophenol in water
Authors: Farhadi Khalil , Farajzadeh Mir , Matin Amir , Hashemi Paria
Published: April 2009

A simple and sensitive dispersive liquid-liquid microextraction method for extraction and preconcentration of pentachlorophenol (PCP) in water samples is presented. After adjusting the sample pH to 3, extraction was performed in the presence of 1% W/V sodium chloride by injecting 1 mL acetone as disperser solvent containing 15 μL tetrachloroethylene as extraction solvent. The proposed DLLME method was followed by HPLC-DAD for determination of PCP. It has good linearity (0.994) with wide linear dynamic range (0.1–1000 μg L−1) and low detection limit (0.03 μg L−1), which makes it suitable for determination of PCP in water samples.
Ultrasound assisted pseudo-digestion for determination of iron and manganese in citric acid fermentation mediums by electrothermal atomic absorption spectroscopy
Authors: Pourhossein Alireza , Madani Masoud , Shahlaei Mohsen , Fakhri Kambiz , Alimohamadi Parisa , Amiri Maryam
Published: April 2009

A sensitive, simple and rapid method for ultra-trace determination of iron and manganese based on ultrasound assisted pseudodigestion in citric acid fermentation medium samples (beet and cane molasses and raw sugar based mediums) is described. Parameters influencing pseudo-digestion, such as sonication time, sample mass and solvent system were fully optimized. Final solutions obtained upon sonication were analyzed by electrothermal atomic absorption spectrometry (ETAAS). The best conditions for metal pseudo-digestion were as follows: a 25, 30 and 20 min sonication time for beet molasses, cane molasses and raw sugar based medium samples, respectively, 0.7 g sample mass of raw sugar based samples, 0.5 g sample mass of molasses based samples and an extraction mixture of concentrated HNO3-H2O2, in 25 mL of solvent. Analytical results obtained for the two metals by ultrasound assisted pseudo-digestion and conventional wet digestion methods showed a good agreement. This method reduces the time required for all treatments (heating to dryness, cooling and separation) in comparison with conventional wet digestion method. The accuracy of the method was tested by comparing the obtained results with that of conventional wet digestion method.
A hydroxyaminophosphane derived from 2-imidazolidone and its unusual structure in solution
Authors: Kühl Olaf , Heiden Waltraud
Published: April 2009

A novel hydroxyamino phosphane was synthesised through the reaction of 2-imidazolidinone with ClPPh2 and subsequently reaction of the resulting bisphosphino derivative with the Grignard reagent BrMgC5H11. The interaction of the pentyl substituent with one of the two phosphino groups and the structure in solution is shown by multinuclear NMR-spectroscopy..
Regional Observation and Sensors
Authors: El Jai Abdelhaq , Hamzaoui Houria
Published: April 2009

Regional Observation and Sensors

The purpose of this short paper is to provide original results related to the choice of the number of sensors and their supports for general distributed parameter systems. We introduce the notion of extended sensors and we show that the observation error decreases when the support of a sensor is widened. We also show that the observation error decreases when the number of sensors increases.
Robust Fractional Adaptive Control Based on the Strictly Positive Realness Condition
Authors: Ladaci Samir , Charef Abdelfatah , Loiseau Jean
Published: April 2009

Robust Fractional Adaptive Control Based on the Strictly Positive Realness Condition

This paper presents a new approach to robust adaptive control, using fractional order systems as parallel feedforward in the adaptation loop. The problem is that adaptive control systems may diverge when confronted with finite sensor and actuator dynamics, or with parasitic disturbances. One of the classical robust adaptive control solutions to these problems makes use of parallel feedforward and simplified adaptive controllers based on the concept of positive realness. The proposed control scheme is based on the Almost Strictly Positive Realness (ASPR) property of the plant. We show that this condition implies also robust stability in the case of fractional order controllers. An application to Model Reference Adaptive Control (MRAC) with a fractional order adaptation rule is provided with an implementable algorithm. A simulation example of a SISO robust adaptive control system illustrates the advantages of the proposed method in the presence of disturbances and noise.
Algebraic Condition for Decomposition of Large-Scale Linear Dynamic Systems
Authors: Górecki Henryk
Published: April 2009

Algebraic Condition for Decomposition of Large-Scale Linear Dynamic Systems

The paper concerns the problem of decomposition of a large-scale linear dynamic system into two subsystems. An equivalent problem is to split the characteristic polynomial of the original system into two polynomials of lower degrees. Conditions are found concerning the coefficients of the original polynomial which must be fulfilled for its factorization. It is proved that knowledge of only one of the symmetric functions of those polynomials of lower degrees is sufficient for factorization of the characteristic polynomial of the original large-scale system. An algorithm for finding all the coefficients of the decomposed polynomials and a general condition of factorization are given. Examples of splitting the polynomials of the fifth and sixth degrees are discussed in detail.
Effective Dual-Mode Fuzzy DMC Algorithms with On-Line Quadratic Optimization and Guaranteed Stability
Authors: Marusak Piotr , Tatjewski Piotr
Published: April 2009

Effective Dual-Mode Fuzzy DMC Algorithms with On-Line Quadratic Optimization and Guaranteed Stability

Dual-mode fuzzy dynamic matrix control (fuzzy DMC-FDMC) algorithms with guaranteed nominal stability for constrained nonlinear plants are presented. The algorithms join the advantages of fuzzy Takagi-Sugeno modeling and the predictive dual-mode approach in a computationally efficient version. Thus, they can bring an improvement in control quality compared with predictive controllers based on linear models and, at the same time, control performance similar to that obtained using more demanding algorithms with nonlinear optimization. Numerical effectiveness is obtained by using a successive linearization approach resulting in a quadratic programming problem solved on-line at each sampling instant. It is a computationally robust and fast optimization problem, which is important for on-line applications. Stability is achieved by appropriate introduction of dual-mode type stabilization mechanisms, which are simple and easy to implement. The effectiveness of the proposed approach is tested on a control system of a nonlinear plant—a distillation column with basic feedback controllers.
Semi-Markov-Based Approach for the Analysis of Open Tandem Networks with Blocking and Truncation
Authors: Oniszczuk Walenty
Published: April 2009

Semi-Markov-Based Approach for the Analysis of Open Tandem Networks with Blocking and Truncation

This paper describes an analytical study of open two-node (tandem) network models with blocking and truncation. The study is based on semi-Markov process theory, and network models assume that multiple servers serve each queue. Tasks arrive at the tandem in a Poisson fashion at the rate λ, and the service times at the first and the second node are non-exponentially distributed with meanssAandsB, respectively. Both nodes have buffers with finite capacities. In this type of network, if the second buffer is full, the accumulation of new tasks by the second node is temporarily suspended (a blocking factor) and tasks must wait on the first node until the transmission process is resumed. All new tasks that find the first buffer full are turned away and are lost (a truncation factor). First, a Markov model of the tandem is investigated. Here, a two-dimensional state graph is constructed and a set of steady-state equations is created. These equations allow calculating state probabilities for each graph state. A special algorithm for transforming the Markov model into a semi-Markov process is presented. This approach allows calculating steady-state probabilities in the semi-Markov model. Next, the algorithms for calculating the main measures of effectiveness in the semi-Markov model are presented. In the numerical part of this paper, the author investigates examples of several semi-Markov models. Finally, the results of calculating both the main measures of effectiveness and quality of service (QoS) parameters are presented.
Qualitative and quantitative phytoseston changes in two different stream-order river segments over a period of twelve years (Grabia and Brodnia, central Poland)
Authors: Sumorok Beata , Żelazna-Wieczorek Joanna , Kostrzewa Krzysztofa
Published: April 2009

Phytoseston studies were carried out at two sites near the town of Łask in the third orderstream segment of the Grabia River and the first order-stream segment of the Brodnia River, in two study periods: 1992-1993 and 2005-2006. Water and seston were sampled twice a month. The chemical parameters of N-NO3, P-PO4 and chlorophyll a were also determined. The aim of the studies was to determine the changes in the nutrient load of these ecosystems in the rivers studied over the course of 12 years and their influence on quantitative and qualitative phytoseston differentiation.

No important differences in the taxonomic composition of the phytoseston between the two rivers were observed. A high participation of diatoms (over 50%), in relation to other algal groups, was recorded in both rivers. Vegetation in the Brodnia River begins to develop one month earlier than in the Grabia River. The greatest changes in the seasonal rate of algal succession occurred in the spring and summer periods, while no considerable changes in seston composition were recorded in the fall or winter periods. A decrease in phytoseston quantity was observed in the second study period. Chlorophyll a content was significantly lower in 2005-2006 than that in 1992-1993.
Denitrification in the sediment of a eutrophic reservoir measured with the isotope pairing technique
Authors: Gruca-Rokosz Renata , Tomaszek Janusz , Koszelnik Piotr
Published: April 2009

Denitrification rates in the bottom sediment of the Rzeszów Reservoir (southeastern Poland) were measured using the isotope pairing technique. At the stations studied rates were reported in the range of about 26 to 610 μmol N2 m-2 h-1, with the figures generally highest in summer. Simple and multiple regression analyses of relationships with selected abiotic factors gave rise to a model that revealed a statistically significant influence on rates of denitrification in the bottom sediment of the Rzeszów Reservoir due to concentrations of nitrate in overlying water, temperature, and the organic matter content in the sediment. The present study confirms that nitrate concentration in the overlying water is the main factor controlling sedimentary denitrification.
The influence of a long-term artificial aeration on the nitrogen compounds exchange between bottom sediments and water in Lake Długie
Authors: Brzozowska Renata , Gawrońska Helena
Published: April 2009

The study was conducted on a degraded Lake Długie in Olsztyn (surface area 26.8 ha, max depth 17.3 m) restored in 1987 - 2000 with the method of the artificial aeration with destratification. The aim of the study was to determine the influence of the applied method on the exchange of nitrogen compounds between the bottom sediments and overlying water. The results revealed that the applied method caused a decrease of nitrogen release from the bottom sediments and influenced the content of this component in the sediments. The observed changes may have been the effect of the intensification of the coupled nitrification-denitrification processes occurring in the aquatic conditions modified by the restoration.
The use of benthic diatoms in estimating water quality of variously polluted rivers
Authors: Szczepocka Ewelina , Szulc Bogusław
Published: April 2009

Two rivers situated in Central Poland, the Bzura and the Pilica, were selected for analysis of their water quality using benthic diatom species as indicators. The Bzura River has previously been strongly contaminated with organic pollutants, while the Pilica River has been classified as having good water quality. Samples were collected from nine sites along the Bzura in April 2003 and seven sites along the Pilica in April 2006. The main aims of the study were to determine the dominant diatom species present in the rivers and to assess their usefulness as biological indicators. Water quality of the rivers was estimated on the basis of the SPI - Specific Pollution sensitivity Index (CEMAGREF 1982) and the GDI - Generic Diatom Index (Coste, Ayphassorho 1991) while trophic status was estimated using TDI - Trophic Diatom Index (Kelly, Whitton 1995).

Indices determining saprobic water pollution (SPI, GDI) indicated water quality of class III and IV for the Bzura River and class II and III for the Pilica River. The trophic status determined on the basis of the TDI index revealed the Bzura water to be classified in the eutrophic-to-hypertrophic zone and that of the Pilica River to the oligo-mesotrophic-to-eutrophic zone.

The diatom taxa that dominated in the Bzura River were species that are generally considered to be tolerant and resistant with respect to organic water pollution, including: Cyclotella meneghiniana Kützing, Gomphonema parvulum (Kützing) Kützing, Nitzschia palea (Kützing) W. Smith, Nitzschia paleacea Grunow, Sellaphora pupula (Kützing) Mereschkovsky, Stephanodiscus hantzschii Grunow, Ulnaria ulna (Nitzsch) Compere. In the Pilica River diatoms from groups that are sensitive and tolerant to organic pollution were seen to dominate, such as: Achnanthidium minutissimum (Kützing) Czarnecki, Aulacoseira granulata (Ehrenberg) Simonsen, Cocconeis neodiminuta Krammer, Cocconeis placentula Ehrenberg, Cocconeis placuntula var. lineata (Ehrenberg) Grunow, Cyclotella radiosa (Grunow) Lemmermann, Fragilaria crotonensis Kitton, Geissleria decussis (Øestrup) Lange-Bertalot et Metzeltin, Melosira varians Agardh, Navicula reichardtiana Lange-Bertalot, Planothidium frequentissimum (Lange-Bertalot) Lange-Bertalot, Pseudostaurosira brevistriata (Grunow) Williams & Round, Rhoicosphenia abbreviata (Agardh) Lange-Bertalot and Staurosira pinnata Ehrenberg.
Object-oriented classification of QuickBird data for mapping seagrass spatial structure
Authors: Urbański Jacek , Mazur Aleksandra , Janas Urszula
Published: April 2009

QuickBird satellite images were processed using object-based analysis to map the spatial structure of seagrass in sandy shoal habitat in the southern Baltic Sea. A three-level ecological model of seagrass landscape, composed of meadows, beds and patches/gaps, was implemented in the multi-scale object domain. Image segmentation was performed at different spatial scales. In order to determine representative scales for bed level and patch/gap level objects, histograms of delineated objects were analyzed. Using object-oriented classification methods, two hierarchically nested maps of seagrass spatial structure were created. The map of patches/gaps was created using the nearest neighbor classification method in the feature space defined by the mean value of band 2 and the value of the proposed seagrass index. Overall map accuracy was 83%. The second map, which depicted the cover density of seagrass beds, was created on the basis of hierarchical relationships between objects at two chosen spatial scale levels. Both maps were exported as vector objects to GIS. Vector-based mapping of seagrass landscape structures at two scales simultaneously provides new possibilities for using landscape metrics and time change detection methods.
Testing of IQ™ 200 Automated Urine Analyzer Analytical Performances in Comparison with Manual Techniques
Authors: Čabarkapa Velibor , Đerić Mirjana , Stošić Zoran
Published: April 2009

Testing of IQ™ 200 Automated Urine Analyzer Analytical Performances in Comparison with Manual Techniques

Automation is necessary in laboratory systems. It enables reduction of time required for sample analysis, as well as standardization of methods. However, automation of urine control in laboratories is much less common than in hematological analyses. Not long ago, the necessary automated systems for urine analysis have also been developed. The objective of this study is a comparison of the IQ™ 200 automated system for urine analyzing with standardized manual urine analyzing techniques. Comparative analysis of 300 samples was performed by the IQ™ 200 system and by the standardized methods of manual microscopy and chemical urine analysis. The results acquired point to very high compatibility between urine analyses by manual techniques and by the automated system IQ™ 200, and in some analyses IQ™ 200 showed higher sensitivity. It can be concluded, with the aim of standardization and shortening of time required for urine analysis, that utilization of automated urine analyzing systems is recommendable, especially in institutions with a large number of daily analyses. This is also supported by the fact that operation procedure on automated systems is much more simple in comparison to manual techniques.
The Efficacy of Different Therapy Protocols for Heart Failure in Patients with Heart Failure and Increased Natriuretic Peptide Level
Authors: Kovačević Radmila , Mirić Milutin
Published: April 2009

The Efficacy of Different Therapy Protocols for Heart Failure in Patients with Heart Failure and Increased Natriuretic Peptide Level

Natriuretic peptide BNP might be clinically useful for monitoring treatment effects in patients with heart failure (HF). In order to investigate the pharmacological effects of different therapy protocols for patients with HF based on the BNP level before and after therapy, we performed an open randomized comparative trial. Sixty-two HF patients with increased natriuretic peptide level, aged 55.82±9.09, II-III NYHA functional classes, ejection fraction (EF) <45%, received a 12-week treatment with either traditional pharmacotherapy for HF with ACE inhibitors and β-blockers (1st group), or ACE inhibitors and angiotensin II receptor blockers (ARBs) (2nd group), or β-blockers and ARBs (3rd group), and ACE inhibitors, β-blockers and ARBs (4th group). We evaluated the BNP plasma level, hemodynamic state (pulmonary capillary wedge pressure (PCWP), cardiac output (CO), EF and exercise capacity. The BNP plasma level decreased significantly in the 4th group of patients who received ACE inhibitors, β-blockers and ARBs, in comparison to other groups. A beneficial influence on hemodynamic and exercise capacity was significantly pronounced in this group, compared to the other therapy regimes. In conclusion, the therapeutic protocol: ACE inhibitors, β-blockers and ARBs in HF patients with increased natriuretic peptide level significantly improves the quality of life, left ventricular function, hemodynamic parameters and exercise capacity. All these changes were accompanied with a decreasing of the BNP plasma level.
The Importance of Determining Human Placental Lactogen in the Third Trimester of Pregnancy
Authors: Durković Jasmina , Mandić Bojana
Published: April 2009

The Importance of Determining Human Placental Lactogen in the Third Trimester of Pregnancy

Human placental lactogen (HPL) is a hormone produced by the placenta with a role in the regulation of fetoplacental growth. In this paper, the results of HPL determination in the third trimester of pregnancy are presented with the aim of testing the sensitivity of this biochemical marker for detecting placental dysfunction, fetal vitality and risk of bad outcome. The tests were performed on 370 women with high-risk pregnancy, between the 20th and 36th week of pregnancy. HPL was determined by an ELISA method using Bioserv Diagnostics tests and the results were read by a STAT-FAX 303+ reader. When compared to normal pregnancy, a significant decrease in the level of HPL biomarker was identified in preeclampsia (p<0.01), whereas in diabetes the serum level of HPL was significantly higher (p<0.01). A significant positive correlation between the level of HPL during pregnancy and the weight of a newborn child, its head circumference and Apgar score was obtained. The results of the research indicate that the maternal concentration of the HPL biomarker is directly connected to the vitality of placental tissue, so that HPL in the third trimester of pregnancy can be used as an indicator of placental insufficiency and fetal vitality.
The Effect of Water Magnetized with Negative Magnetic Field on Effectiveness of Selected Zoocides in the Control of Two-Spotted Spider Mite (Tetranychus Urticae Koch)
Authors: Górski Romuald , Wachowiak Marek , Tomczak Michał
Published: April 2009

The Effect of Water Magnetized with Negative Magnetic Field on Effectiveness of Selected Zoocides in the Control of Two-Spotted Spider Mite (Tetranychus UrticaeKoch)

The results of experiments showed an effect of negative magnetic field on some chemical and physical properties of water. A slight increase in iron (Fe) content, a decrease in zinc (Zn) level and an increase in surface tension (Dc) were observed in the study. At the same time the effect of magnetically modified water on an increase in effectiveness of tested zoocides was observed in the control of the two-spotted spider mite (Tetranychus urticaeKoch). A strong and statistically significant increase in the effectiveness of zoocide Talstar 100 EC was recorded after the application of one and three magnetizers, preparation Omite 30 WP after the application of two magnetizers, acaricide Magus 200 SC after the application of one and two magnetizers as well as a simultaneous use of one magnetizer and two semi-rings. Acaricide Ortus 05 SC showed a marked increase in the effectiveness in all treatments with the use of magnetically modified water.
Discrimination Between Celery Cultivars with the Use of Rapd Markers
Authors: Domblides Arthur , Domblides Helen , Kharchenko Victor
Published: April 2009

Discrimination Between Celery Cultivars with the Use of Rapd Markers

Screening of celery cultivars with random amplified primers is a way of avoiding mistakes in distinguishing similar genotypes. Six primers showed distinct polymorphism between the studied cultivars. The number of bands varied from 7 to 13. Suitable primers generated 52 markers of which 22 were polymorphic. A similarity matrix was created using Jaccard's coefficient. The group average method was employed to construct a dendrogram. Based on RAPD marker profiles the cultivars were grouped into three clusters coinciding with the cultivated types, var. dulce (salad celery), and var. rapaceum (turnip celery), var. secalinum (cutting celery). The salad celery entries were similar to plants of turnip celery with similarity 0.73, and the distance between genotypes of cutting celery and turnip celery was 0.68. Although only 12 cultivars have been analysed, the specific product amplified with OPX1 was observed in the three studied cultivars of cutting celery.