bluuebunny/crossref_metadata_2025 huggingface dataset:
Extreme weather and experience influence reproduction in an endangered bird
Authors: Reichert Brian E. , Cattau Christopher E. , Fletcher Robert J. , Kendall William L. , Kitchens Wiley M.
Published: July 2012

Extreme weather events, such as droughts and heat waves, are expected to become more severe and more frequent in the coming years, and understanding their impacts on demographic rates is of increasing interest to both evolutionary ecologists and conservation practitioners. An individual's breeding probability can be a sensitive indicator of the decision to initiate reproductive behavior under varying environmental conditions, has strong fitness consequences, and can be considered the first step in a life history trade‐off between allocating resources for breeding activities or self‐survival.

Using a 14‐year time series spanning large variation in climatic conditions and the entirety of a population's breeding range, we estimated the effects of extreme weather conditions (drought) on the state‐specific probabilities of breeding and survival of an endangered bird, the Florida Snail Kite (Rostrhamus sociabilisplumbeus). Our analysis accounted for uncertainty in breeding status assignment, a common source of uncertainty that is often ignored when states are based on field observations. Breeding probabilities in adult kites (>1 year of age) decreased during droughts, whereas the probability of breeding in young kites (1 year of age) tended to increase. Individuals attempting to breed showed no evidence of reduced future survival. Although population viability analyses of this species and other species often implicitly assume that all adults will attempt to breed, we find that breeding probabilities were significantly <1 for all 13 estimable years considered. Our results suggest that experience is an important factor determining whether or not individuals attempt to breed during harsh environmental conditions and that reproductive effort may be constrained by an individual's quality and/or despotic behavior among individuals attempting to breed.
Effects of organic matter amendments on net primary productivity and greenhouse gas emissions in annual grasslands
Authors: Ryals Rebecca , Silver Whendee L.
Published: July 2012

Most of the world's grasslands are managed for livestock production. A critical component of the long‐term sustainability and profitability of rangelands (e.g., grazed grassland ecosystems) is the maintenance of plant production. Amending grassland soils with organic waste has been proposed as a means to increase net primary productivity (NPP) and ecosystem carbon (C) storage, while mitigating greenhouse gas emissions from waste management. Few studies have evaluated the effects of amendments on the C balance and greenhouse gas dynamics of grasslands. We used field manipulations replicated within and across two rangelands (a valley grassland and a coastal grassland) to determine the effects of a single application of composted green waste amendments on NPP and greenhouse gas emissions over three years. Amendments elevated total soil respiration by 18% ± 4% at both sites but had no effect on nitrous oxide or methane emissions. Carbon losses were significantly offset by greater and sustained plant production. Amendments stimulated both above‐ and belowground NPP by 2.1 ± 0.8 Mg C/ha to 4.7 ± 0.7 Mg C/ha (mean ± SE) over the three‐year study period. Net ecosystem C storage increased by 25–70% without including the direct addition of compost C. The estimated magnitude of net ecosystem C storage was sensitive to estimates of heterotrophic soil respiration but was greater than controls in five out of six fields that received amendments. The sixth plot was the only one that exhibited lower soil moisture than the control, suggesting an important role of water limitation in these seasonally dry ecosystems. Treatment effects persisted over the course of the study, which were likely derived from increased water‐holding capacity in most plots, and slow‐release fertilization from compost decomposition. We conclude that a single application of composted organic matter can significantly increase grassland C storage, and that effects of a single application are likely to carry over in time.
Sintered properties and sintering behavior of MgO-ZrO2 composite hydrogel prepared by coprecipitation technique
Authors: Das Sukhen , Mitra N.K. , Das Sudip
Published: July 2012

Active precursor powders of MgO-ZrO2 composite system were prepared in three
different mole ratio by electrolytic interaction of inorganic salts in
aqueous phase. Complete hydrolysis occurred at the critical instability point
of the system at pH 9. The amorphous precursor powders exhibited very high
specific surface area. The sintered properties of the composite system are
dependent on mole ratio of MgO:ZrO2, sintering temperature and the rate of
crystallization of constituent phases. The presence of periclase grains and
cubic stabilized ZrO2 particles in the sintered body was confirmed by X-ray
diffraction analysis while scanning electron micrographs indicated that MgO
particles occupy the inter-granular positions between ZrO2 polycrystals.
Mechanical-chemical synthesis Ba0.77Sr0.23TiO3
Authors: Kosanovic D. , Obradovic N. , Zivojinovic J. , Filipovic S. , Maricic A. , Pavlovic V. , Tang Y. , Ristic M.M.
Published: July 2012

Barium-Strontium-Titanate Ba0.77Sr0.23TiO3 was prepared from starting
materials BaCO3, SrCO3 and TiO2 through solid-state reactions. Mixtures of
these oxides are mechanically activated in a high-energy planetary ball mill
at different time intervals from 0 to 120 minutes. In order to obtain
information on phase composition, crystal structure was determent by X-ray
diffraction. It was observed that after 80 minutes in process synthesis
Ba0.77Sr0.23TiO3 started Thermal analyzes were performed in order to
determine the characteristic temperatures of the processes that occur in the
solid phase. Particle size distribution, together with electron microscopy
scanning has given us very useful information about the morphology of the
powder.
Synthesis of TiN-Si3N4 composites from rutile and quartz by carbothermal reduction nitridation
Authors: Chen Kai , Huang Zhaohui , Fang Minghao , Liu Yan-Gai
Published: July 2012

TiN-Si3N4 composite powders were prepared by carbothermal reduction
nitridation using rutile and quartz as raw materials. The influence of
temperature and carbon addition on the phase evolution and microstructure of
the products were investigated. The equilibrium phase diagram of Si-C-N-O and
Ti-C-N-O system at different temperatures under 0.2 MPa nitrogen pressure was
drew. The results show that the optimum parameters for synthesizing TiN-Si3N4
by carbothermal reduction nitridation process are carbon addition of
stoichiometric content, temperature of 1873 K for 4 h and nitrogen pressure
of 0.2 MPa. The produced TiN-Si3N4 in this experiment exist in granular and
hexagonal columnar shape, and the average particle size of the synthesized
powders is 2 ~ 10 ?m.
Synthesis of barium-zinc-titanate ceramics
Authors: Obradovic N. , Nikolic M.V. , Nikolic N. , Filipovic S. , Mitric M. , Pavlovic V. , Nikolic P.M. , Djordjevic A.R. , Ristic M.M.
Published: July 2012

Mixtures of BaCO3, ZnO and TiO2 powders, with molar ratio of 1:2:4, were
mechanically activated for 20, 40 and minutes in a planetary ball mill. The
resulting powders were compacted into pellets and isothermally sintered at
1250?C for 2h with a heating rate of 10?C/min. X-ray diffraction analysis
of obtained powders and sintered samples was performed in order to
investigate changes of the phase composition. The microstructure of sintered
samples was examined by scanning electron microscopy. The photoacoustic phase
and amplitude spectra of sintered samples were measured as a function of the
laser beam modulating frequency using a transmission detection configuration.
Fitting of experimental data enabled determination of photoacoustic
properties including thermal diffusivity. Based on the results obtained
correlation between thermal diffusivity and experimental conditions, as well
the samples microstructure characteristics, was discussed.
Mechanical properties and microstructure of Al2O3/TiAl in situ composites doped with Cr and V2O5
Authors: Zhang Kun , Fen Wang , Zhu Jianfeng , Wu Huae
Published: July 2012

Al2O3/TiAl in situ composites doped with Cr and V2O5 were successfully
prepared from Ti, Al, TiO2, Cr and V2O5 by hot pressing. The effect of in
situ formed Al2O3 content on the phase composition, microstructure and
mechanical properties of Al2O3/TiAl composites were investigated. The results
show that the as-synthesized composites mainly consisted of ?-TiAl/?2-Ti3Al
matrix and dispersive Al2O3 reinforcing phases. The in situ formed fine Al2O3
ceramic particles mainly disperse on the grain boundaries of TiAl, resulting
in refinement of TiAl matrix, which improves the mechanical properties of the
Al2O3/TiAl in situ composite. The composite with 7.54 at.% Al2O3 possesses
the maximum flexural strength and fracture toughness of 335.38 MPa and 5.39
MPa m1/2, respectively. The strengthening mechanism was also discussed in
detail.
SiC synthesis using natural Mg-silicates
Authors: Devecerski A. , Posarac M. , Dimitrijevic M. , Rosic M. , Volkov-Husovic T. , Brankovic G.
Published: July 2012

The silicon carbide powders are prepared by carbothermal reduction of
domestic mineral resources (white and brown sepiolite), at relatively low
temperatures (1200 - 1600oC). Carbothermal reduction process is greatly
influenced by chemical composition of sepiolites and type of carbon used.
Obtained SiC powders consist of fine ?-SiC particles and did not retain the
fibrous morphology of sepiolites. Catalytical influence of Fe is attributed
to formation of iron-silicide and its potentionaly important role in removal
of Mg-species, i.e. reduction of Mg2SiO4 and MgO into Mg(g).
Formation of magnetic microstructure of the nanosized NiFe2O4 synthesized via solid-state reaction
Authors: Zák T. , Cosovic V. , Cosovic A. , David B. , Talijan N. , Zivkovic D.
Published: July 2012

Magnetic NiFe2O4 structure formation was studied through structural,
compositional and magnetic characterization of obtained reaction products of
a simple, high yielding and low-cost solid-state reaction. Initial annealing
of the starting oxides mixture at 700?C did not allow us to observe formation
of the desired magnetic phase. In contrast, subsequent thermomagnetic
measurements up to 800?C indicated the considerable increase of the magnetic
moment, which can be reasonably assigned to the changes in phase composition
and formation of magnetic NiFe2O4 structure during the heating cycle of
measurements. Nanosized NiFe2O4 phase formation has been confirmed by the
following XRD and MS phase analyses and its nanocrystalline structure by XRD
and SEM/TEM techniques. The obtained hysteresis loop taken after TM
measurements suggest the increased volume of magnetically active material and
thus additionally support the previous findings.
Effect of Temperature on the Degree of Conversion and Working Time of Dual-Cured Resin Cements Exposed to Different Curing Conditions
Authors: Oliveira M , Cesar PF , Giannini M , Rueggeberg FA , Rodrigues J , Arrais CA
Published: July 2012

Objectives

This study evaluated the degree of conversion (DC) and working time (WT) of two commercial, dual-cured resin cements polymerized at varying temperatures and under different curing-light accessible conditions, using Fourier transformed infrared analysis (FTIR).

Materials and Methods

Calibra (Cal; Dentsply Caulk) and Variolink II (Ivoclar Vivadent) were tested at 25°C or preheated to 37°C or 50°C and applied to a similar-temperature surface of a horizontal attenuated-total-reflectance unit (ATR) attached to an infrared spectrometer. The products were polymerized using one of four conditions: direct light exposure only (600 mW/cm2) through a glass slide or through a 1.5- or 3.0-mm-thick ceramic disc (A2 shade, IPS e.max, Ivoclar Vivadent) or allowed to self-cure in the absence of light curing. FTIR spectra were recorded for 20 min (1 spectrum/s, 16 scans/spectrum, resolution 4 cm−1) immediately after application to the ATR. DC was calculated using standard techniques of observing changes in aliphatic-to-aromatic peak ratios precuring and 20-min postcuring as well as during each 1-second interval. Time-based monomer conversion analysis was used to determine WT at each temperature. DC and WT data (n=6) were analyzed by two-way analysis of variance and Tukey post hoc test (p=0.05).

Results

Higher temperatures increased DC regardless of curing mode and product. For Calibra, only the 3-mm-thick ceramic group showed lower DC than the other groups at 25°C (p=0.01830), while no significant difference was observed among groups at 37°C and 50°C. For Variolink, the 3-mm-thick ceramic group showed lower DC than the 1-mm-thick group only at 25°C, while the self-cure group showed lower DC than the others at all temperatures (p=0.00001). WT decreased with increasing temperature: at 37°C near 70% reduction and at 50°C near 90% for both products, with WT reduction reaching clinically inappropriate times in some cases (p=0.00001).

Conclusion

Elevated temperature during polymerization of dual-cured cements increased DC. WT was reduced with elevated temperature, but the extent of reduction might not be clinically acceptable.
Sirenomelia: Case Reports and Current Concepts of Pathogenesis
Authors: Pillay Minnie , Yesodharan Dhanya , Narayanan Dhanya Lakshmi , Jojo Annie , Luiz Newton , Nampoothiri Sheela
Published: July 2012

We present 2 cases of sirenomelia and highlight the recent theories about its pathogenesis. Both cases had a large aberrant abdominal umbilical artery (AAUA) arising from the aorta, suggesting vascular steal as the pathophysiology. However, the bilateral upper limb defects noted in 1 case, the reported 10% association of holoprosencephaly and anencephaly, and the reports of sirenomelia with normal umbilical arteries point to the alternative caudal dysgenesis (CD) theory. This proposes that an insult at the early blastogenic stage interferes with the formation of the notochord, resulting in abnormal development of caudal structures, an AAUA, and occasional neural tube defects. We have also analyzed the implications of the similarities between sirenomelia/CD and the VATER association; the increased risk of CD but not sirenomelia in infants of diabetic mothers; the fact that sirenomelia, holoprosencephaly, and the VATER association are all more common in monozygotic twins; the experimental production of sirenomelia in mice; and the possible genetic implications of the co-occurrence of sirenomelia and CD.
Prediction of Asphalt Creep Compliance Using Artificial Neural Networks
Authors: Zofka A. , Yut I.
Published: July 2012

Creep compliance of the hot-mix asphalt (HMA) is a primary input of the current pavement thermal cracking prediction model used in the US. This paper discusses a process of training an Artificial Neural Network (ANN) to correlate the creep compliance values obtained from the Indirect Tension (IDT) with similar values obtained on small HMA beams from the Bending Beam Rheometer (BBR). In addition, ANNs are also trained to predict HMA creep compliance from the creep compliance of asphalt binder and vice versa using the BBR setup. All trained ANNs exhibited a very high correlation of 97 to 99 percent between predicted and measured values. The binder creep compliance functions built on the ANN-predicted discrete values also exhibited a good correlation when compared with the laboratory experiments. However, the simulation of trained ANNs on the independent dataset produced a significant deviation from the measured values which was most likely caused by the differences in material composition, such as aggregate type and gradation, presence of recycled additives, and binder type.
Moisture and Frost Resistance of the Recycled Base Rehabilitated with the Foamed Bitumen Technology / Odpornosc Na Oddziaływanie Wody I Mrozu Podbudowy W Technologii Recyklingu Z Asfaltem Spienionym
Authors: Iwanski M. , Chomicz-Kowalska A.
Published: July 2012

The technology of recycling with foamed bitumen is a new technology of road rehabilitation. Due to the climatic conditions in the Central European countries, road pavement structure should be moisture and frost resistant. Because of its specific production conditions, this is especially important for pavements rehabilitation with the cold recycling technology. Determining the physical and mechanical properties, as well as moisture and frost resistance, depends on binder and filler contents. They are the key elements before its use for road building. The tests presented here have been performed on mineral recycled base mixes with foamed bitumen. The material from the existing layers was used. The content of bitumen binder amounted to 2.0%, 2.5%, 3.0% and 3.5%, while that of cement to 1.0%, 1.5%, 2.0%, 2.5%. The results were subject to the optimization process. This allowed to state that with the use of 2.5% foamed bitumen and 2.0% of cement, the base had the required properties, as well as the moisture and frost resistance.
Evaluation of Load Values Using the Gumbel Model
Authors: Wolinski S. , Pytlowany T.
Published: July 2012

The paper deals with application of the Gumbel model to evaluation of the environmental loads. According to recommendations of Eurocodes, the conventional method of determining return period and characteristic values of loads utilizes the theory of extremes and implicitly assumes that the cumulative distribution function of the annual or other basic period extremes is the Gumbel distribution. However, the extreme value theory shows that the distribution of extremes asymptotically approaches the Gumbel distribution when the number of independent observations in each observation period from which the maximum is abstracted increases to infinity. Results of calculations based on simulation show that in practice the rate of convergence is very slow and significantly depends on the type of parent results distribution, values of coefficient of variation, and number of observation periods. In this connection, a straightforward purely empirical method based on fitting a curve to the observed extremes is suggested.
The Influence of Higher Modes Vibrations on Local Cracks in Node of Lattice Girders Bridges / Wpływ Wyzszych Postaci Drgan Na Zaistnienie Lokalnych Spekan W Wezle Mostu Kratowego
Authors: Pradelok S.
Published: July 2012

Several previous investigations on failure of a certain type lattice girders railway bridge (on so called BJD line) have not convincingly explained reasons nor have they described potential hazards. This paper attempts to provide an answer, employing static, dynamic, and fatigue analysis of the structure, focusing on previously not analyzed vibrations of elements constituting a lattice node. Detailed models of two types of such nodes - damaged and non- damaged were compared, inside carefully defined limits of applicability.
Analysis of Influence of Vibrations on Humans in Buildings in Standards Approach / Analiza Wpływu Drgan Na Ludzi W Budynkach W Ujeciu Normowym
Authors: Kawecki J. , Kowalska A.
Published: July 2012

People living in buildings may be exposed to dynamic actions. In the diagnosis and design of buildings there is an increasing need of taking into account these activities and verification of compliance of the building requirements for vibration comfort of people residing in buildings. This study presents the results of analysis of such criteria in the following standards: Polish PN-88/B-02171 [1], British BS 6472-1 [2], German DIN 4150 [3], and ISO international standards [4,5]. Basing on the results of this analysis and on the review of selected items of literature, the application of standards recommendations in diagnosis and design of buildings, as well as areas for further research on this subject is indicated. This article is an extended version of the conference paper [6] presented on the conference Urban Transport 2011.
Hydrogen peroxide induced by the fungicide prothioconazole triggers deoxynivalenol (DON) production by Fusarium graminearum
Authors: Audenaert Kris , Callewaert Elien , Höfte Monica , De Saeger Sarah , Haesaert Geert
Published: July 2012

Hydrogen peroxide induced by the fungicide prothioconazole triggers deoxynivalenol (DON) production by Fusarium graminearum

Fusarium head blight is a very important disease of small grain cereals with F. graminearum as one of the most important causal agents. It not only causes reduction in yield and quality but from a human and animal healthcare point of view, it produces mycotoxins such as deoxynivalenol (DON) which can accumulate to toxic levels. Little is known about external triggers influencing DON production. In the present work, a combined in vivo/in vitro approach was used to test the effect of sub lethal fungicide treatments on DON production. Using a dilution series of prothioconazole, azoxystrobin and prothioconazole + fluoxastrobin, we demonstrated that sub lethal doses of prothioconazole coincide with an increase in DON production 48 h after fungicide treatment. In an artificial infection trial using wheat plants, the in vitro results of increased DON levels upon sub lethal prothioconazole application were confirmed illustrating the significance of these results from a practical point of view. In addition, further in vitro experiments revealed a timely hyperinduction of H2O2 production as fast as 4h after amending cultures with prothioconazole. When applying H2O2 directly to germinating conidia, a similar induction of DON-production by F. graminearum was observed. The effect of sub lethal prothioconazole concentrations on DON production completely disappeared when applying catalase together with the fungicide. These cumulative results suggest that H2O2 induced by sub lethal doses of the triazole fungicide prothioconazole acts as a trigger of DON biosynthesis. In a broader framework, this work clearly shows that DON production by the plant pathogen F. graminearum is the result of the interaction of fungal genomics and external environmental triggers.
Fusarium wilt of water melon caused by Fusarium solani in Hungary
Authors: Turóczi Gy. , Posta K. , Badenszky L. , Bán R.
Published: July 2012

Fusarium wilt of water melon caused byFusarium solaniin Hungary

Water melon growers in Hungary have been recently reported a disease resembling that of Fusarium wilt developed on Fusarium resistant cultivars. Diseased samples from different regions of Hungary were collected in 2008 and 2009. The pathogen has been successfully isolated and identified asFusarium solani.All of the isolates are host specific, but are very aggressive on water melon cultivars resistant toF. oxysporumf.sp. niveum. Severe infections occurred only in those fields where water melon has been grown continously for several years, but the pathogen is present in the soil of other fields as well.
Effect of fungicide application on Wheat Head Blight, occurrence of Fusarium spp. and mycotoxin production
Authors: Baturo-Cieśniewska A. , Lukanowski A. , Kolenda M.
Published: July 2012

Effect of fungicide application on Wheat Head Blight, occurrence of Fusarium spp. and mycotoxin production

The aim of the study was to determine if azoxystrobin and metconazole used for the control of wheat FHB at half, full, and quarter more the recommended dose rate may affect in differentiated way on the occurrence of Fusarium spp. and their ability to mycotoxin production in harvested grain, in wheat ears artificially inoculated with two DON-producing isolates of F. culmorum. Macroscopic evaluation showed high incidence of fusariosis. Plant health in the plots where the heads were artificially inoculated and fungicide was not applied was similar to the protected ones. Only increasing the dose metconazole resulted in a stronger reduction of fusariosis. The advantageous effect of azoxystrobin was not observed. Mycological analysis of harvested grain showed the presence of a number of F. culmorum, but from samples sprayed with metconazole it was isolated in smaller quantities. Also F. avenaceum, F. graminearum, F. poae and F. tricinctum were isolated. Molecular analysis showed the presence of F. culmorum in all samples of harvested grain. Also genes from Tri cluster were identified, involved in the synthesis of type-A and type-B trichothecenes - especially DON and 3Ac-DON. Chromatography revealed the presence of small quantities of mycotoxins. In all samples DON and 3Ac-DON were predominant. In general, F. culmorum isolate, which caused weaker symptoms of FHB and was less numerously isolated from grain that the other one, produced smaller amounts of mycotoxins. Samples protected with azoxystrobin contain the largest quantities of DON. Effect of different doses of fungicides on the number of mycotoxins was not clearly established.
Impact of agronomy on HT-2 and T-2 toxin content of oats
Authors: Edwards Simon , Anderson Eric
Published: July 2012

Impact of agronomy on HT-2 and T-2 toxin content of oats

Surveys of oats in the UK and Nordic countries have identified high concentrations of HT-2 and T-2 can occur in unprocessed oats. HT-2 and T-2 are two closely related type A trichothecenes and two of the most toxic fusarium mycotoxins. There is currently no legislation on HT-2 and T-2, however, there is a discussion limit of 500 μg kg-1 in unprocessed oats. A previous survey identified that variety, previous crop, cultivation, fungicide use and some other factor(s) within organic oat production, which was not within the model, were all significant agronomic factors in the determination of HT-2 and T-2 concentrations of UK oats. Possible agronomy within conventional compared to organic agriculture would include the use of inorganic fertilisers and plant growth regulators (PGR). Oats harvested from two series of agronomic field experiments were analysed for the combined concentration of HT-2 and T-2 (HT2+T2) using ELISA. Experiments were repeated for both winter and spring varieties over two years. The first experiments were of a factorial design with three varieties, three nitrogen rates and plus/minus a PGR (chlormequat). The second series had twelve fungicide regimes. The results identified that there were no significant differences in HT-2+T-2 between samples from oat plots that received different rates of inorganic nitrogen, a PGR, or a range of different fungicide regimes. There was however a significant difference between varieties for both winter and spring variety experiments.
Exponential stability of nonlinear neutral type systems
Authors: Gil' Michael
Published: July 2012

Exponential stability of nonlinear neutral type systems

Nonlinear neutral type systems with distributed and discrete delays are considered. Explicit exponential stability conditions are established. The main tool is a combined usage of the recent norm estimates for the matrix resolvents, the Urysohn theorem and estimates for fundamental solutions of the linear parts.
Computation of initial conditions and inputs for given outputs of fractional and positive discrete-time linear systems
Authors: Kaczorek Tadeusz
Published: July 2012

Computation of initial conditions and inputs for given outputs of fractional and positive discrete-time linear systems

The problem of computation of initial conditions and inputs for given outputs of fractional standard and positive discrete-time linear systems is formulated and solved. Necessary and sufficient conditions for existence of solution to the problem are established. It is shown that there exist the unique solutions to the problem only if the pair (A, C) of the system is observable.
Regular design equations for the discrete reduced-order Kalman filter
Authors: Hippe Peter
Published: July 2012

Regular design equations for the discrete reduced-order Kalman filter

In the presence of white Gaussian noises at the input and the output of a system Kalman filters provide a minimum-variance state estimate. When part of the measurements can be regarded as noise-free, the order of the filter is reduced. The filter design can be carried out both in the time domain and in the frequency domain. In the case of full-order filters all measurements are corrupted by noise and therefore the design equations are regular. In the presence of noise-free measurements, however, they are not regular so that standard software cannot readily be applied in a time-domain design. In the frequency domain the spectral factorization of the non-regular polynomial matrix equation causes no problems. However, the known proof of optimality of the factorization result requires a regular measurement covariance matrix. This paper presents regular (reduced-order) design equations for the reduced-order discrete-time Kalman filter in the time and in the frequency domains so that standard software is applicable. They also allow to formulate the conditions for the stability of the filter and to prove the optimality of the existing solutions.
Comparison of two controllers for directional control of a hybrid electric vehicle
Authors: Dash Basanta , Subudhi Bidyadhar
Published: July 2012

Comparison of two controllers for directional control of a hybrid electric vehicle

Directional response of a vehicle implies changing its direction when sustaining lateral acceleration while moving on the road. From this response, the vehicle's explicit capabilities as well as its contribution to the system performance of the driver/vehicle combination are obtained. In vehicle control literature, handling is often used interchangeably with cornering, turning, or directional response. This paper focuses one aspect of the handling i.e. directional response. Two different controllers, namely a PID controller and a Fuzzy Logic Controller (FLC) for a hybrid electric vehicle (HEV) are designed in this paper to control the vehicle's steering in a smooth lane change maneuver. The performances of the aforesaid two controllers have been studied extensively in this paper. For achieving an improved path tracking and directional response, parameters of both the PID and FLC have been tuned and their performances have been compared. Further, the effect of changing the scale factors in the fuzzy logic approach to obtaining directional response is presented. To validate the above two control performances, a nonlinear simulation model of a HEV is developed and is used in simulation studies. Both the controllers track the desired directional signal efficiently. Both PID and Fuzzy controllers provide competitive performances. Although with the assumption of all parameters of the vehicle available PID controller exhibits slightly better dynamic performance but in the real-world scenario the fuzzy controller is preferred due to its robustness i.e. it does not depend on the parameters of the vehicle.
LMI based control design for linear systems with distributed time delays
Authors: Filasová Anna , Gontkovič Daniel , Krokavec Dušan
Published: July 2012

LMI based control design for linear systems with distributed time delays

The paper concerns the problem of stabilization of continuous-time linear systems with distributed time delays. Using extended form of the Lyapunov-Krasovskii functional candidate, the controller design conditions are derived and formulated with respect to the incidence of structured matrix variables in the linear matrix inequality formulation. The result give sufficient condition for stabilization of the system with distributed time delays. It is illustrated with a numerical example to note reduced conservatism in the system structure.
Neuro-fuzzy control design of processes in chemical technologies
Authors: Blahová Lenka , Dvoran Ján , Kmeťová Jana
Published: July 2012

Neuro-fuzzy control design of processes in chemical technologies

The paper presents design of neuro-fuzzy control and its application in chemical technologies. Our approach to neuro-fuzzy control is a combination of the neural predictive controller and the neuro-fuzzy controller (Adaptive Network-based Fuzzy Inference System - ANFIS). These controllers work in parallel. The output of ANFIS adjusts the output of the neural predictive controller to enhance the control performance. Such design of an intelligent control system is applied to control of the continuous stirred tank reactor and laboratory mixing process.
Implementation of a high-accuracy spatial network for measurements of steel constructions
Authors: Štroner Martin , Urban Rudolf , Braun Jaroslav
Published: July 2012

Implementation of a high-accuracy spatial network for measurements of steel constructions

The paper deals with a project for the measurement and evaluation of a unique local spatial network with a high degree of accuracy at the MCE Slaný Company. The accuracy requirements were very high; the standard deviation in measuring the components of a steel construction before its final assembly is about ones of millimeters.
Pooling of low flow regimes using cluster and principal component analysis
Authors: Števková Andrea , Sabo Miroslav , Kohnová Silvia
Published: July 2012

Pooling of low flow regimes using cluster and principal component analysis

This article deals with the regionalization of low flow regimes lower than Q95 in Slovakia. For the regionalization of 219 small and medium-sized catchments, we used a catchment area running from 4 to 500 km2 and observation periods longer than 20 years. The relative frequency of low flows lower than Q95 was calculated. For the regionalization, the nonhierarchical clustering K-means method was applied. The Silhouette coefficient was used to determine the right number of clusters. The principal components were found from the pooling variables on the principal components. The K-means clustering method was applied. Next, we compared the differences between the two methods of pooling data into regional types. The results were compared using an association coefficient.
Factors Associated With Physical Therapy Services Received for Individuals With Cerebral Palsy in an Outpatient Pediatric Medical Setting
Authors: Bailes Amy F. , Succop Paul
Published: July 2012

Background

Limited information is available regarding physical therapy use for individuals with cerebral palsy (CP).

Objectives

The purpose of this study was to evaluate the association of Gross Motor Function Classification System (GMFCS) level, age, race, sex, and type of insurance with the total physical therapy units received over a 1-year period for individuals with CP in this outpatient pediatric medical setting.

Design

This was a cross-sectional study.

Methods

Four hundred twenty-five individuals with CP (GMFCS level I, 36%; level II, 15%; level III, 13%; level IV, 19%; and level V, 17%) were identified retrospectively through their electronic medical records. A one-way analyses of variance (ANOVA) was performed for each explanatory variable followed by a multiway ANOVA that adjusted for other variables to find the best model to explain total physical therapy units received.

Results

A significant difference in total therapy units received was found among GMFCS levels (F=6.91; df=4,420; P<.001), age groups (F=4.76; df=3,421; P=.028), and type of insurance (F=8.09; df=2,422; P=.004). No significant difference in physical therapy received was found for the factors of sex and race. The final multifactorial model indicates a significant main effect of insurance and a GMFCS by age interaction accounting for 19% of the variability (F=4.45; df=21,403; P<.001).

Limitations

This study is cross-sectional and examines physical therapy services received in a pediatric medical setting in 1 geographic region of the United States.

Conclusions

The results of this study provide insight into how therapy received varies for individuals with CP. Future studies should evaluate additional variables that may affect physical therapy services received.
Exercise for People in Early- or Mid-Stage Parkinson Disease: A 16-Month Randomized Controlled Trial
Authors: Schenkman Margaret , Hall Deborah A. , Barón Anna E. , Schwartz Robert S. , Mettler Pamela , Kohrt Wendy M.
Published: July 2012

Background

Exercise confers short-term benefits for individuals with Parkinson disease (PD).

Objective

The purpose of the study was to compare short- and long-term responses among 2 supervised exercise programs and a home-based control exercise program.

Design

The 16-month randomized controlled exercise intervention investigated 3 exercise approaches: flexibility/balance/function exercise (FBF), supervised aerobic exercise (AE), and home-based exercise (control).

Setting

This study was conducted in outpatient clinics.

Patients

The participants were 121 individuals with PD (Hoehn & Yahr stages 1–3).

Interventions

The FBF program (individualized spinal and extremity flexibility exercises followed by group balance/functional training) was supervised by a physical therapist. The AE program (using a treadmill, bike, or elliptical trainer) was supervised by an exercise trainer. Supervision was provided 3 days per week for 4 months, and then monthly (16 months total). The control group participants exercised at home using the National Parkinson Foundation Fitness Counts program, with 1 supervised, clinic-based group session per month.

Measurements

Outcomes, obtained by blinded assessors, were determined at 4, 10, and 16 months. The primary outcome measures were overall physical function (Continuous Scale—Physical Functional Performance [CS-PFP]), balance (Functional Reach Test [FRT]), and walking economy (oxygen uptake [mL/kg/min]). Secondary outcome measures were symptom severity (Unified Parkinson's Disease Rating Scale [UPDRS] activities of daily living [ADL] and motor subscales) and quality of life (39-item Parkinson's Disease Quality of Life Scale [PDQ-39]).

Results

Of the 121 participants, 86.8%, 82.6%, and 79.3% completed 4, 10, and 16 months, respectively, of the intervention. At 4 months, improvement in CS-PFP scores was greater in the FBF group than in the control group (mean difference=4.3, 95% confidence interval [CI]=1.2 to 7.3) and the AE group (mean difference=3.1, 95% CI=0.0 to 6.2). Balance was not different among groups at any time point. Walking economy improved in the AE group compared with the FBF group at 4 months (mean difference=−1.2, 95% CI=−1.9 to −0.5), 10 months (mean difference=−1.2, 95% CI=−1.9 to −0.5), and 16 months (mean difference=−1.7, 95% CI=−2.5 to −1.0). The only secondary outcome that showed significant differences was UPDRS ADL subscale scores: the FBF group performed better than the control group at 4 months (mean difference=−1.47, 95% CI=−2.79 to −0.15) and 16 months (mean difference=−1.95, 95% CI=−3.84 to −0.08).

Limitations

Absence of a non-exercise control group was a limitation of the study.

Conclusions

Findings demonstrated overall functional benefits at 4 months in the FBF group and improved walking economy (up to 16 months) in the AE group.
Identification of high-risk carotid artery stenosis: motion of intraplaque contents detected using B-mode ultrasonography
Authors: Kashiwazaki Daina , Yoshimoto Tetsuyuki , Mikami Taisei , Muraki Mutsuko , Fujimoto Shin , Abiko Kagari , Kaneko Sadao
Published: July 2012

Object

Identification of the risk of rupture and vulnerability of arterial plaque is not yet clearly understood. The aim of this study was to assess the clinical features of the motion of intraplaque contents (MIC) detected by B-mode ultrasonography. The MIC is characterized by the peculiar movement of the intraplaque contents that is not synchronized with the heartbeat; however, the movement of the carotid artery (CA) wall depends on the heartbeat.

Methods

From January 2008 to November 2010, 1798 consecutive patients with transient ischemic attacks (TIAs) or acute ischemic stroke underwent CA ultrasonography for the examination of the MIC. Patients with CA stenosis greater than 50% were followed up until they underwent carotid endarterectomy or CA angioplasty and stent placement. If neither of these procedures were used, the patients were followed up at 90 days. Chi-square and Mann-Whitney tests were performed to compare the categorical and continuous demographic data and risk factors. The effect of the MIC on the rate of recurrent cerebral ischemia was examined using Kaplan-Meier and univariate Cox regression analyses.

Results

One hundred and fifteen patients had CA stenosis greater than 50%. Among these 115 patients, 58 with a total of 59 CA stenoses had MIC. Twenty-four recurrent ischemic events were associated with MIC, whereas only 6 such events occurred in the absence of MIC. The MIC decreased event-free survival (log-rank test = 15.8, p < 0.001); univariate Cox analysis confirmed that MIC increased the risk of a recurrent ischemic event (HR 5.12, 95% CI 2.08–12.58; p < 0.001).

Conclusions

The MIC is one of the findings of vulnerable plaques. The MIC is more useful in predicting the recurrence of TIAs or ischemic events in patients with symptomatic CA stenosis.
Bifrontal encephalogaleosynangiosis for children with moyamoya disease
Authors: Ogiwara Hideki , Morota Nobuhito
Published: July 2012

Object

Several operative techniques have been reported to increase the cerebral blood flow (CBF) of the anterior cerebral artery (ACA) territory in patients with moyamoya disease. However, the optimal procedure has not yet been determined. This study compared the efficacy of performing bifrontal encephalogaleosynangiosis (EGS) using a craniotomy with performing EGS using bur holes.

Methods

The authors retrospectively analyzed surgical results of pediatric patients with moyamoya disease treated using encephaloduroarteriosynangiosis (EDAS) and bifrontal EGS with a craniotomy, or EGS with bur holes, for the purpose of improving the ischemia of the ACA territory. Patients' demographic data, clinical presentations, surgical therapies, and clinical outcomes were reviewed.

Results

Nine patients underwent EDAS with bifrontal EGS using a craniotomy. Three patients underwent EDAS with EGS using bur holes for 5 cerebral hemispheres (1 bur hole in 2 hemispheres, 2 bur holes in 2 hemispheres, and 3 bur holes in 1 hemisphere). The mean follow-up period was 46.8 months (range 7–96 months). Preoperative symptoms improved in all patients in each group. The collateral circulation in the ACA territory made by EGS was divided into 3 groups according to postoperative angiography results: Group A (revascularization of more than two-thirds of the ACA territory), Group B (revascularization between one-third and two-thirds), and Group C (revascularization less than one-third). Of 5 hemispheres treated with EGS using bur holes, 1 was evaluated as Group B and 4 as Group C. Of 18 hemispheres treated with bifrontal EGS using a craniotomy, 8 were evaluated as Group A, 7 as Group B, and 3 as Group C. The patients who underwent bifrontal EGS using a craniotomy showed significantly better revascularization than those who underwent EGS using bur holes (p = 0.0065). Cerebral blood flow in the ACA territory improved in 13 (92.9%) of 14 hemispheres in patients treated with bifrontal EGS. In contrast, only 3 (60%) of 5 hemispheres demonstrated an increase of CBF in patients treated with EGS using bur holes. A trend was demonstrated for better improvement with bifrontal EGS (p = 0.08).

Conclusions

Encephaloduroarteriosynangiosis with bifrontal EGS using a craniotomy demonstrated better revascularization and improvement of CBF in the ACA territory than with EGS using bur holes. Bifrontal EGS using a craniotomy is considered to be a simple, safe, and effective surgical procedure for improvement of the ischemia of the ACA territory in pediatric patients with moyamoya disease.
A single spinal lesion arising from an intradural meningioma contiguous with an extradural lymphoma
Authors: Jankowski Pawel P. , Baird Lissa C. , Keshavarzi Sassan , Goolsby Mary E. , Taylor William R. , Nguyen Andrew D.
Published: July 2012

The authors describe here a unique case of contiguous, synchronous meningioma and lymphoma in the spinal column. Both tumors were present at the same vertebral level, one intradural and the other extradural. A patient presented with bilateral leg pain, acute weakness, and sensory loss in the lower extremities. Magnetic resonance imaging revealed an intradural mass at T6–7 with ambiguous boundaries relative to the thecal sac and compressing the spinal cord. The patient underwent resection of the epidural and intradural mass at T6–7. Histopathology revealed the epidural specimen to be a double-hit B-cell lymphoma and the intradural mass to be a transitional meningioma. Postoperatively, the patient did well, with an immediate return of strength and sensation. A postoperative MR image showed complete resection of the intradural mass. The authors suggest that biopsy may be prudent in patients with known systemic lymphoma presenting with a spinal lesion that has unclear boundaries relative to the thecal sac prior to commencing radiation and chemotherapy.
Ultrasonic-Assisted Enzymolysis to Improve the Antioxidant Activities of Peanut (Arachin conarachin L.) Antioxidant Hydrolysate
Authors: Yu Lina , Sun Jie , Liu Shaofang , Bi Jie , Zhang Chushu , Yang Qingli
Published: July 2012

The objective of this work is to provide a theoretical basis for preparing peanut antioxidant hydrolysate in order to improve its antioxidant activities. Therefore, response surface methodology (RSM) based on the Box-Behnken design was used to optimize ultrasonic-assisted enzymolysis for the purpose of preparing peanut antioxidant hydrolysate. Results indicated that the DPPH free radical scavenging activity of peanut hydrolysate could reach 90.06% under the following optimum conditions: ultrasonic power of 150.0 w, reaction temperature of 62.0 °C, incubation time of 25.0 min, and initial pH value of 8.5. The DPPH free radical scavenging rate of peanut hydrolysate from ultrasonic-assisted enzymolysis improved comparing with that of peanut hydrolysate from protease hydrolysis alone. The peanut antioxidant hydrolysate was found to display eight improved kinds of antioxidant activities. In conclusion, the optimal ultrasonic-assisted enzymolysis technology conditions described in this paper, appear to be beneficial for preparing peanut antioxidant hydrolysate.
Decidual Macrophages Are Significantly Increased in Spontaneous Miscarriages and Over-Express FasL: A Potential Role for Macrophages in Trophoblast Apoptosis
Authors: Guenther Sabine , Vrekoussis Thomas , Heublein Sabine , Bayer Birgit , Anz David , Knabl Julia , Navrozoglou Iordanis , Dian Darius , Friese Klaus , Makrigiannakis Antonis , Jeschke Udo
Published: July 2012

Decidual macrophages (DM) are the second most abundant population in the fetal-maternal interface. Their role has been so far identified as being local immuno-modulators favoring the maternal tolerance to the fetus. Herein we investigated tissue samples from 11 cases of spontaneous miscarriages and from 9 cases of elective terminations of pregnancy. Using immunohistochemistry and dual immunofluorescence we have demonstrated that in spontaneous miscarriages the DM are significantly increased. Additionally, we noted a significant up-regulation of macrophage FasL expression. Our results further support a dual role for DM during pregnancy and miscarriages. We hypothesize that the baseline DM population in normal pregnancy is in line with an M2 phenotype supporting the ongoing gestation. In contrast, during spontaneous miscarriages, the increased FasL-expressing population could be a part of an M1 phenotype participating in Fas/FasL-related apoptosis. Our results highlight a new aspect of macrophage biology in pregnancy physiology and pathophysiology. Further studies with larger samples are needed to verify the current results and evaluate their clinical impact.