bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of a Broadband Parallel-Coupled Microstrip Filters without Spurious Resonances
Authors: Abd-Elrazzak Maher M.
Published: March 2008

A design of parallel-coupled microstrip bandpass filters without spurious resonance is presented. Two different techniques are used to eliminate this response at twice the passband frequency (2fo). The first one is based on usage of suspended substrate, while the second is carried out by shorting the parallel-coupled lines to the ground plane through two shorting walls. The numerical results show that a broadband filter can be obtained by the suppression of the spurious response. The finite difference time domain (FDTD) with the perfect matched layer (PML) is used in the present analysis. The obtained results are compared with the available published data and good agreements are found.
Modified Natural Rubber Induced Aqueous to Toluene Phase Transfer of Gold and Platinum Colloids
Authors: Abu Bakar Mohamad , Ismail Jamil , Teoh Cheng Hoon , Tan Wei Leng , Abu Bakar Noor Hana Hanif
Published: March 2008

Citrate‐stabilized gold and platinum particles were prepared in aqueous phase and transferred to toluene phase by employing 2‐propanol as the transfer agent. It was found that the modified natural rubber (ENR) induced the phase transfer and assisted the dispersion of the citrate‐free metal particles into the organic phase. The amounts of gold and platinum transferred are 93.4% and 86.1%, respectively. This phase transfer technique produced organosols of smaller particle sizes and narrower size distribution with self‐assembly arrangements when compared to those prepared via the previous in situ preparations. The respective average particle size and standard deviation of gold before and after phase transfer were 6.3 ± 1.7 nm and 7.2 ± 1.3 nm, while for platinum they were 4.0 ± 0.7 nm and 4.2 ± 0.8 nm. The slight increase in the average sizes and overall size distributions in both metals after transfer was attributed to multiparticle aggregation in the organic phase.
Myeloperoxidase: A New Biomarker of Inflammation in Ischemic Heart Disease and Acute Coronary Syndromes
Authors: Loria Valentina , Dato Ilaria , Graziani Francesca , Biasucci LuigiM.
Published: March 2008

Myeloperoxidase (MPO) is an enzyme stored in azurophilic granules of polymorphonuclear neutrophils and macrophages and released into extracellular fluid in the setting of inflammatory process. The observation that myeloperoxidase is involved in oxidative stress and inflammation has been a leading factor to study myeloperoxidase as a possible marker of plaque instability and a useful clinical tool in the evaluation of patients with coronary heart disease. The purpose of this review is to provide an overview of the pathophysiological, analytical, and clinical characteristics of MPO and to summarize the state of art about the possible clinical use of MPO as a marker for diagnosis and risk stratification of patients with acute coronary syndrome (ACS).
On π‐Images of Locally Separable Metric Spaces
Authors: An Tran Van , Dung Nguyen Vangiven-names
Published: March 2008

We characterize π‐images of locally separable metric spaces
by means of covers having π‐property. As its application, we obtain characterizations
of compact‐covering (sequence‐covering, pseudo‐sequence‐covering, and sequentially quotient)
π‐images of locally sparable metric spaces.
On the Lower Classes of Some Mixed Fractional Gaussian Processes with Two Logarithmic Factors
Authors: El-Nouty Charles
Published: March 2008

We introduce the fractional mixed fractional Brownian sheet and investigate the small ball behavior of its sup‐norm statistic by establishing a general result on the small ball probability of the sum of two not necessarily independent joint Gaussian random vectors. Then, we state general conditions and characterize the sufficiency part of the lower classes of some statistics of the above process by an integral test. Finally, when we consider the sup‐norm statistic, the necessity part is given by a second integral test.
Chitosan Derivatives/Calcium Carbonate Composite Capsules Prepared by the Layer‐by‐Layer Deposition Method
Authors: Sasaki Takashi , Shimizu Misato , Wu Yusong , Sakurai Kensuke
Published: March 2008

Core/shell capsules composed of calcium carbonate whisker core (rod‐like shape) and chitosan/chitosansulfate shell were prepared by the layer‐by‐layer deposition technique. Two chitosan samples of different molecular weights (Mw = 9.7 × 104 and 1.09 × 106g · mol−1) were used as original materials. Hollow capsules were also obtained by dissolution of the core in hydrochloric acid. Electron microscopy revealed that the surface of the shell is rather ragged associated with some agglomerates. The shell thickness l obeys a linear relation with respect to the number of deposited layers m as l = md + a(a > 0). The values of d (thickness per layer) were 4.0 and 1.0 nm for the higher and lower Mw chitosan materials, respectively, both of which are greater than the thickness of the monolayer. The results suggest that the feature of the deposition does not obey an ideal homogeneous monolayer‐by‐monolayer deposition mechanism. Shell crosslinked capsules were also prepared via photodimerization reaction of cinnamoyl groups after a deposition of cinnamoyl chitosan to the calcium carbonate whisker core. The degree of crosslink was not enough to stabilize the shell structure, and hollow capsule was not obtained.
A Markov Chain Approach to Randomly Grown Graphs
Authors: Knudsen Michael , Wiuf Carsten
Published: March 2008

A Markov chain approach to the study of randomly grown graphs is
proposed and applied to some popular models that have found use in biology
and elsewhere. For most randomly grown graphs used in biology,
it is not known whether the graph or properties of the graph converge (in
some sense) as the number of vertices becomes large. Particularly, we study
the behaviour of the degree sequence, that is, the number of vertices with
degree 0, 1, …,
in large graphs, and apply our results to the partial duplication
model. We further illustrate the results by application to real data.
Commutators of the Hardy‐Littlewood Maximal Operator with BMO Symbols on Spaces of Homogeneous Type
Authors: Hu Guoen , Lin Haibo , Yang Dachun
Published: March 2008

Weighted Lp for p ∈ (1, ∞) and weak‐type endpoint estimates with
general weights are established for commutators of the Hardy‐Littlewood maximal
operator with BMO symbols on spaces of homogeneous type. As an application, a
weighted weak‐type endpoint estimate is proved for maximal operators associated
with commutators of singular integral operators with BMO symbols on spaces of
homogeneous type. All results with no weight on spaces of homogeneous type are
also new.
Efficiently Synchronized Spread‐Spectrum Audio Watermarking with Improved Psychoacoustic Model
Authors: He Xing , Scordilis Michael S.
Published: March 2008

This paper presents an audio watermarking scheme which is based on an efficiently synchronized spread‐spectrum technique and a new psychoacoustic model computed using the discrete wavelet packet transform. The psychoacoustic model takes advantage of the multiresolution analysis of a wavelet transform, which closely approximates the standard critical band partition. The goal of this model is to include an accurate time‐frequency analysis and to calculate both the frequency and temporal masking thresholds directly in the wavelet domain. Experimental results show that this watermarking scheme can successfully embed watermarks into digital audio without introducing audible distortion. Several common watermark attacks were applied and the results indicate that the method is very robust to those attacks.
Reliability Assessment of 2400 MWth Gas-Cooled Fast Reactor Natural Circulation Decay Heat Removal in Pressurized Situations
Authors: Bassi C. , Marques M.
Published: March 2008

As the 2400 MWth gas-cooled fast reactor concept makes use of passive safety features in combination with active safety systems, the question of natural circulation decay heat removal (NCDHR) reliability and performance assessment into the ongoing probabilistic safety assessment in support to the reactor design, named “probabilistic engineering assessment” (PEA), constitutes a challenge. Within the 5th Framework Program for Research and Development (FPRD) of the European Community, a methodology has been developed to evaluate the reliability of passive systems characterized by a moving fluid and whose operation is based on physical principles, such as the natural circulation. This reliability method for passive systems (RMPSs) is based on uncertainties propagation into thermal-hydraulic (T-H) calculations. The aim of this exercise is finally to determine the performance reliability of the DHR system operating in a “passive” mode, taking into account the uncertainties of parameters retained for thermal-hydraulical calculations performed with the CATHARE 2 code. According to the PEA preliminary results, exhibiting the weight of pressurized scenarios (i.e., with intact primary circuit boundary) for the core damage frequency (CDF), the RMPS exercise is first focusing on the NCDHR performance at these T-H conditions.
Investigation of the α−γ−α Phase Transformation in Steel: High-Temperature In Situ EBSD Measurements
Authors: Lischewski I. , Kirch D. M. , Ziemons A. , Gottstein G.
Published: March 2008

A newly developed laser powered heating stage for commercial SEMs in combination with automated established electron backscatter diffraction (EBSD) data acquisition is presented. This novel experimental setup can be used to achieve more information about microstructure and orientation changes during grain growth, recrystallization, recovery, and phase transformations. First results on the α−γ−α
phase transformation in steel within 886∘C–900∘C are presented.
PPAR‐γ, Microglial Cells, and Ocular Inflammation: New Venues for Potential Therapeutic Approaches
Authors: Malchiodi-Albedi Fiorella , Matteucci Andrea , Bernardo Antonietta , Minghetti Luisa
Published: March 2008

The last decade has witnessed an increasing interest for the role played by the peroxisome proliferator‐activated receptor‐γ (PPAR‐γ) in controlling inflammation in peripheral organs as well as in the brain. Activation of PPAR‐γ has been shown to control the response of microglial cells, the main macrophage population found in brain parenchyma, and limit the inflammation. The anti‐inflammatory capacity of PPAR‐γ agonists has led to the hypothesis that PPAR‐γ might be targeted to modulate degenerative brain diseases in which inflammation has been increasingly recognized as a significant component. Recent experimental evidence suggests that PPAR‐γ agonists could be exploited to treat ocular diseases such as diabetic retinopathy, age‐related macular degeneration, autoimmune uveitis, and optic neuritis where inflammation has relevant role. Additional PPAR‐γ agonist beneficial effects could involve amelioration of retinal microcirculation and inhibition of neovascularization. However, PPAR‐γ activation could, in some instances, aggravate the ocular pathology, for example, by increasing the synthesis of vascular endothelial growth factor, a proangiogenic factor that could trigger a vicious circle and further deteriorate retinal perfusion. The development of new in vivo and in vitro models to study ocular inflammation and how to modulate for the eye benefit will be instrumental for the search of effective therapies.
Distinct Effects of Contraction Agonists on the Phosphorylation State of Cofilin in Pulmonary Artery Smooth Muscle
Authors: Dai Yan-Ping , Bongalon Shaner , Mutafova-Yambolieva Violeta N. , Yamboliev Ilia A.
Published: March 2008

We hypothesized that agonist-induced contraction correlates with the phospho-cofilin/cofilin (P-CF/CF) ratio in pulmonary artery (PA) rings and cultured smooth muscle cells (PASMCs). PA rings were used for isometric contractions and along with PASMCs for assay of P-CF/CF by isoelectric focusing and immunoblotting. The P-CF/CF measured 22.5% in PA and differentiated PASMCs, but only 14.8% in undifferentiated PASMCs. With comparable contraction responses in PA, endothelin-1 (100 nM) and norepinephrine (1 μM) induced a 2-fold increase of P-CF/CF, while angiotensin II (1 μM) induced none. All agonists activated Rho-kinase and LIMK2, and activation was eliminated by inhibition of Rho-kinase. Microcystin LF (20 nM) potentiated the angiotensin II, but not the 5-hydroxytryptamine (1 μM)-mediated increase of P-CF/CF. In conclusion, all tested agonists activate the Rho-kinase-LIMK pathway and increase P-CF/CF. Angiotensin II activates PP2A and counteracts the LIMK-mediated CF phosphorylation. CF phosphorylation stabilizes peripheral actin structures and may contribute to the maximal contraction of PA.
Dislocation Nucleation and Pileup under a Wedge Contact at Nanoscale
Authors: Gao Y. F. , Lou J.
Published: March 2008

Indentation responses of crystalline materials have been found to be radically different at micrometer and nanometer scales. The latter is usually thought to be controlled by the nucleation of dislocations. To explore this physical process, a dislocation mechanics study is performed to determine the conditions for the nucleation of a finite number of dislocations under a two‐dimensional wedge indenter, using the Rice‐Thomson nucleation criterion. The configurational force on the dislocation consists of the applied force, the image force, and the interaction force between dislocations. Dislocations reach equilibrium positions when the total driving force equals the effective Peierls stress, giving a set of nonlinear equations that can be solved using the Newton‐Raphson method. When the apex angle of the wedge indenter increases, the critical contact size for dislocation nucleation increases rapidly, indicating that dislocation multiplication near a blunt wedge tip is extremely difficult. This geometric dependence agrees well with experimental findings.
Properties of Cement Mortar with Phosphogpysum under Steam Curing Condition
Authors: Mun Kyoungju , So Seungyoung
Published: March 2008

The purpose of this study is to utilize waste PG as an admixture for concrete products cured by steam. For the study, waste PG was classified into 4 forms (dehydrate,β-hemihydrate, III-anhydrite, and II-anhydrite), which were calcined at various temperatures. Also, various admixtures were prepared with PG, fly-ash (FA), and granulated blast-furnace slag (BFS). The basic properties of cement mortars containing these admixtures were analyzed and examined through X-ray diffraction, scanning electron microscopy, compressive strength, and acid corrosion resistance. According to the results, cement mortars made with III-anhydrite of waste PG and BFS exhibited strength similar to that of cement mortars made with II-anhydrite. Therefore, III-anhydrite PG calcined at lower temperature can be used as a steam curing admixture for concrete second production.
Multivariate Interpolation Functions of Higher‐Order q‐Euler Numbers and Their Applications
Authors: Ozden Hacer , Cangul Ismail Naci , Simsek Yilmaz
Published: March 2008

The aim of this paper, firstly, is to construct generating functions of q‐Euler numbers and polynomials of higher order by applying the fermionic p‐adic q‐Volkenborn integral, secondly, to define multivariate q‐Euler zeta function (Barnes‐type Hurwitz q‐Euler zeta function) and l‐function which interpolate these numbers and polynomials at negative integers, respectively. We give relation between Barnes‐type Hurwitz q‐Euler zeta function and multivariate q‐Euler l‐function. Moreover, complete sums of products of these numbers and polynomials are found. We give some applications related to these numbers and functions as well.
The Application of Counter‐Rotating Turbine in Rocket Turbopump
Authors: Fei Tang , Xiaolu Zhao , Jianzhong Xu
Published: March 2008

Counter rotating turbine offers advantages on weight, volume, efficiency, and maneuverability relative to the conventional turbine because of its special architecture. Nowadays, it has been a worldwide research emphasis and has been used widely in the aeronautic field, while its application in the astronautic field is seldom investigated. Researches of counter rotating turbine for rocket turbopump are reviewed in this paper. A primary analysis of a vaneless counter rotating‐turbine configuration with rotors of different diameters and rotational speeds is presented. This unconventional configuration meets the requirements of turbopump and may benefit the performance and reliability of rocket engines.
Barley Genomics: An Overview
Authors: Sreenivasulu Nese , Graner Andreas , Wobus Ulrich
Published: March 2008

Barley (Hordeum vulgare), first domesticated in the Near East, is a well-studied crop in terms of genetics, genomics, and breeding and qualifies as a model plant forTriticeaeresearch. Recent advances made in barley genomics mainly include the following: (i) rapid accumulation of EST sequence data, (ii) growing number of studies on transcriptome, proteome, and metabolome, (iii) new modeling techniques, (iv) availability of genome-wide knockout collections as well as efficient transformation techniques, and (v) the recently started genome sequencing effort. These developments pave the way for a comprehensive functional analysis and understanding of gene expression networks linked to agronomically important traits. Here, we selectively review important technological developments in barley genomics and related fields and discuss the relevance for understanding genotype-phenotype relationships by using approaches such as genetical genomics and association studies. High-throughput genotyping platforms that have recently become available will allow the construction of high-density genetic maps that will further promote marker-assisted selection as well as physical map construction. Systems biology approaches will further enhance our knowledge and largely increase our abilities to design refined breeding strategies on the basis of detailed molecular physiological knowledge.
Photocatalytic Degradation of Chlorobenzene by TiO2 in High‐Temperature and High‐Pressure Water
Authors: Kometani N. , Inata S. , Shimokawa A. , Yonezawa Y.
Published: March 2008

A fluidized‐bed‐type flow reactor available for the photocatalytic treatment of the suspension of model soil under high‐temperature, high‐pressure conditions was designed. An aqueous suspension containing hydrogen peroxide (H2O2) as an oxidizer and inorganic oxides as a model soil, titania (TiO2), silica (SiO2), or kaoline (Al2Si2O5(OH) 4) was continuously fed into the reactor with the temperature and the pressure controlled to be T = 20–400∘C and P = 30 MPa, respectively. The degradation of chlorobenzene (CB) in water was chosen as a model oxidation reaction. It appeared that most of the model soils are not so harmful to the SCWO treatment of CB in solutions. When the TiO2 suspension containing H2O2 was irradiated with near‐UV light, the promotion of the degradation caused by photocatalytic actions of TiO2 was observed at all temperatures. Persistence of the photocatalytic activity in the oxidation reaction in high‐temperature, high‐pressure water would open up a possibility of the development of the hybrid process based on the combination of SCWO process and TiO2 photocatalysis for the treatment of environmental pollutants in soil and water, which are difficult to handle by conventional SCWO process or catalytic SCWO process alone.
On Integral Operator Defined by Convolution Involving Hybergeometric Functions
Authors: Al-Shaqsi K. , Darus M.
Published: March 2008

For λ > −1 and μ ≥ 0, we consider a liner operator on the class 𝒜 of analytic functions in the unit disk defined by the convolution , where , and introduce a certain new subclass of 𝒜 using this operator. Several interesting properties of these classes are obtained.
Exp‐Function Method for Solving Huxley Equation
Authors: Zhou Xin-Wei
Published: March 2008

Huxley equation is a core mathematical framework for modern biophysically based neural modeling. It is often useful to obtain a generalized solitary solution for fully understanding its physical meanings. There are many methods to solve the equation, but each method can only lead to a special solution. This paper suggests a relatively new method called the Exp‐function method for this purpose. The obtained result includes all solutions in open literature as special cases, and the generalized solution with some free parameters might imply some fascinating meanings hidden in Huxley equation.
Hydrothermal Preparation of Visible‐Light‐Driven N‐Br‐Codoped TiO2 Photocatalysts
Authors: Sheng Yonggang , Xu Yao , Jiang Dong , Liang Liping , Wu Dong , Sun Yuhan
Published: March 2008

Using a facile hydrothermal method, N‐Br‐codoped TiO2 photocatalyst that had intense absorption in visible region was prepared at low temperature (100oC), through a direct reaction between nanocrystalline anatase TiO2 solution and cetyltrimethylammonium bromide (CTAB). The results of X‐ray photoelectron spectroscopy (XPS) showed the existence of N‐Ti‐N, O‐Ti‐N‐R, Ti3+ (attribute to the doped Br atoms by charge compensation), and TiOxNy species, indicating the successful codoping of N and Br atoms, which were substituted for lattice oxygen without any influence on the crystalline phase of TiO2. In contrast to the N‐doped sample, the N‐Br‐codoped TiO2 photocatalyst could more readily photodegrade methylene blue (MB) under visible‐light irradiation. The visible‐light catalytic activity of thus‐prepared photocatalyst resulted from the synergetic effect of the doped nitrogen and bromine, which not only gave high absorbance in the visible‐light range, but also reduced electron‐hole recombination rate.
Unbounded Solutions of a Boundary Value Problem for Abstract nth‐Order Differential Equations on an Infinite Interval
Authors: Liu Zhenbin , Liu Lishan , Wu Yonghong , Zhao Jing
Published: March 2008

The existence of unbounded nonnegative solutions of a boundary value problem for nth‐order differential equations defined on an infinite interval is obtained by means of the Mönch fixed‐point theorem. An example is then presented to demonstrate the application of our results.
Nanostructural Organization of Naturally Occurring Composites—Part I: Silica‐Collagen‐Based Biocomposites
Authors: Ehrlich Hermann , Heinemann Sascha , Heinemann Christiane , Simon Paul , Bazhenov Vasily V. , Shapkin Nikolay P. , Born René , Tabachnick Konstantin R. , Hanke Thomas , Worch Hartmut
Published: March 2008

Glass sponges, as examples of natural biocomposites, inspire investigations aiming at both a better understanding of biomineralization mechanisms and novel developments in the synthesis of nanostructured biomimetic materials. Different representatives of marine glass sponges of the class Hexactinellida (Porifera) are remarkable because of their highly flexible basal anchoring spicules. Therefore, investigations of the biochemical compositions and the micro‐ and nanostructure of the spicules as examples of naturally structured biomaterials are of fundamental scientific relevance. Here we
present a detailed study of the structural and biochemical properties of the basal spicules of the marine glass sponge Monorhaphis chuni. The results show unambiguously that in this glass sponge a fibrillar protein of collagenous nature is the template for the silica mineralization in all silica‐containing structural layers of the spicule. The structural similarity and homology of collagens derived from M. chuni spicules to other sponge and vertebrate collagens have been confirmed by us using FTIR, amino acid analysis and mass spectrometric sequencing techniques. We suggest that nanomorphology of silica formed on proteinous structures could be determined as an example of biodirected epitaxial nanodistribution of amorphous silica phase on oriented fibrillar collagen templates. Finally, the present work includes a discussion relating to silica‐collagen‐based hybrid materials for practical applications as biomaterials.
Comparison of C‐Reactive Protein and Serum Amyloid A Protein in Septic Shock Patients
Authors: Cicarelli Domingos Dias , Vieira Joaquim Edson , Benseñor Fábio Ely Martins
Published: March 2008

Septic shock is a severe inflammatory state caused by an infectious agent. Our purpose was to investigate serum amyloid A (SAA) protein and C‐reactive protein (CRP) as inflammatory markers of septic shock patients. Here we evaluate 29 patients in postoperative period, with septic shock, in a prospective study developed in a surgical intensive care unit. All eligible patients were monitored over a 7‐day period by sequential organ failure assessment (SOFA) score, daily CRP, SAA, and lactate measurements. CRP and SAA strongly correlated up to the fifth day of observation but were not good predictors of mortality in septic shock.
Nanomechanics of Single Crystalline Tungsten Nanowires
Authors: Cimalla Volker , Röhlig Claus-Christian , Pezoldt Jörg , Niebelschütz Merten , Ambacher Oliver , Brückner Klemens , Hein Matthias , Weber Jochen , Milenkovic Srdjan , Smith Andrew Jonathan , Hassel Achim Walter
Published: March 2008

Single crystalline tungsten nanowires were prepared from directionally solidified NiAl‐W alloys by a chemical release from the resulting binary phase material.
Electron back scatter diffraction (EBSD) proves that they are single crystals having identical crystallographic orientation.
Mechanical investigations such as bending tests, lateral force measurements, and mechanical resonance measurements were performed on 100–300 nm diameter wires. The wires could be either directly employed using micro tweezers, as a singly clamped nanowire or in a doubly clamped nanobridge.
The mechanical tests exhibit a surprisingly high flexibility for such a brittle material resulting from the small dimensions. Force displacement measurements on singly clamped W nanowires by an AFM measurement allowed the determination of a Young′s modulus of 332 GPa very close to the bulk value of 355 GPa.
Doubly clamped W nanowires were employed as resonant oscillating nanowires in a magnetomotively driven resonator running at 117 kHz. The Young′s modulus determined from this setup was found to be higher 450 GPa which is likely to be an artefact resulting from the shift of the resonance frequency by an additional mass loading.
A Low‐Cost BIST Scheme for Test Vector Embedding in Accumulator‐Generated Sequences
Authors: Voyiatzis Ioannis
Published: March 2008

Test set embedding built‐in self test (BIST) schemes are a class of pseudorandom BIST techniques where the test set is embedded into the sequence generated by the BIST pattern generator, and they displace common pseudorandom schemes in cases where reverse‐order simulation cannot be applied. Single‐seed embedding schemes embed the test set into a single sequence and demand extremely small hardware overhead since no additional control or memory to reconfigure the test pattern generator is required. The challenge in this class of schemes is to choose the best pattern generator among various candidate configurations. This, in turn, calls for a need to evaluate the location of each test pattern in the sequence as fast as possible, in order to try as many candidate configurations as possible for the test pattern generator. This problem is known as the test vector‐embedding problem.
In this paper we present a novel solution to the test vector‐embedding problem for sequences generated by accumulators. The time overhead of the solution is of the order O(1). The applicability of the presented method for embedding test sets for the testing of real‐world circuits is investigated through experimental results in some well‐known benchmarks; comparisons with previously proposed schemes indicate that comparable test lengths are achieved, while the time required for the calculations is accelerated by more than 30 times.
Printed UWB Antenna with Coupled Slotted Element for Notch‐Frequency Function
Authors: Bao X. L. , Ammann M. J.
Published: March 2008

A novel printed monopole antenna employing a slotted‐plate, which is electromagnetically coupled to the microstrip‐fed planar element, is proposed to provide notch‐frequency function. This technique enables stopband characteristics with improved control, compared to placing the slot in the microstrip‐fed element. A detailed investigation of the rejectband properties has been made for the UWB antenna. Measured data for the optimized case show the 10 dB return loss bandwidth to be 9.8 GHz (from 2.80 GHz to 12.60 GHz) with a notchband frequency from 5.15 GHz to 5.825 GHz. Propagation measurements indicate that the electromagnetically coupled slot provides a greater reduction in stopband gain for the three principal planes, compared to placing the slot in the fed element. This is desirable to mitigate interference from WLAN systems. A full parametric study of the antenna is presented.
Prevention of Oxidative Stress‐Induced Retinal Pigment Epithelial Cell Death by the PPARγAgonists, 15‐Deoxy‐Delta 12, 14‐Prostaglandin J2
Authors: Chang Jason Y. , Bora Puran S. , Bora Nalini S.
Published: March 2008

Cellular oxidative stress plays an important role in retinal pigment epithelial (RPE) cell death during aging and the development of age‐related macular degeneration. Early reports indicate that during phagocytosis of rod outer segments, there is an increase of RPE oxidative stress and an upregulation of PPARγ mRNA in these cells. These studies suggest that activation of PPARγ may modulate cellular oxidative stress. This paper presents a brief review of recent studies that investigate RPE oxidative stress under various experimental conditions. This is followed by a detailed review on those reports that examine the protective effect of the natural PPARγ ligand, 15d‐PGJ2, against RPE oxidative stress. This agent can upregulate glutathione and prevent oxidant‐induced intracellular reactive oxygen species accumulation, mitochondrial depolarization, and apoptosis. The cytoprotective effect of this agent, however, is not shared by other PPARγ agonists. Nonetheless, this property of 15d‐PGJ2 may be useful in future development of pharmacological tools against retinal diseases caused by oxidative stress.
Generating Complete Bifurcation Diagrams Using a Dynamic Environment Particle Swarm Optimization Algorithm
Authors: Barrera Julio , Flores Juan J. , Fuerte-Esquivel Claudio
Published: March 2008

A dynamic system is represented as a set of equations that specify how variables
change over time. The equations in the system specify how to compute the
new values of the state variables as a function of their current values and the values
of the control parameters. If those parameters change beyond certain values,
the system exhibits qualitative changes in its behavior. Those qualitative changes
are called bifurcations, and the values for the parameters where those changes occur
are called bifurcation points. In this contribution, we present an application
of particle swarm optimization methods for dynamic environments for plotting bifurcation
diagrams used in the analysis of dynamical systems. The use of particle
swarm optimization methods presents various advantages over traditional methods.
Complex Impedance Spectroscopic Properties of Ceramics
Authors: Khatri Praveen , Behera Banarji , Srinivas V. , Choudhary R. N. P.
Published: March 2008

The polycrystalline sample of was prepared by a high-temperature solid-state reaction technique. The effect of temperature on impedance parameters was studied using an impedance analyzer in a wide frequency range (  Hz). The real and imaginary parts of complex impedance trace semicircles in the complex plane. The temperature-dependent plots reveal the presence of both bulk and grain boundary effects above C. The bulk resistance of the material decreases with rise in temperature. This exhibits a typical negative temperature coefficient of resistance (NTCR) behavior of the material. The modulus analysis suggests a possible hopping mechanism for electrical transport processes of the material. The nature of variation of dc conductivity suggests the Arrhenius type of electrical conductivity.
Elastofibroma Dorsi: An Uncommon Benign Pseudotumour
Authors: Chandrasekar C. R. , Grimer R. J. , Carter S. R. , Tillman R. M. , Abudu A. , Davies A. M. , Sumathi V. P.
Published: March 2008

Elastofibroma dorsi is an uncommon benign soft tissue pseudotumour usually located at the lower pole of the scapula, deep to serratus anterior, and often attached to the periosteum of the ribs, presenting with long history of swelling and occasionally pain and discomfort. This lesion is usually seen in patients over the age of 50 years and is not uncommonly mistaken as a malignant tumour because of its size and location deep to the periscapular muscles. Review of the orthopaedic oncology database of 17 500 patients revealed that there were 15 patients with elastofibroma dorsi. There were 12 males and 3 females, mean age at diagnosis of 68.4 years range 51–79 years. The diagnosis was confirmed by MRI in 3 patients, excision biopsy in 3 patients, trucut biopsy in 8 patients and open biopsy in 1 patient. Eight patients had excision of the lesion which was symptomatic. There have been no recurrences. We highlight the clinical and radiological presentation of elastofibroma dorsi to increase awareness of its existence and management.
Modified Vertical Rectus Abdominis Musculocutaneous Flap for Limb Salvage Procedures in Proximal Lower Limb Musculoskeletal Sarcomas
Authors: Khalil Haitham H. , El-Ghoneimy Ahmed , Farid Yasser , Ebeid Walid , Afifi Ahmed , Elaffandi Ahmed , Mahboub Tarek
Published: March 2008

Introduction and aim. Management of complicated wounds after tumor extipiration of pelvic and proximal lower limb musculoskeletal sarcoma represents an essential component in the outcome of these patients. The authors present modified vertical rectus abdominis musculocutaneous (VRAM) flap techniques to reconstruct extensive defects after debridment of these complicated wounds.Material and Methods. Over a period of 4 years (2002–2005), 5 men and 2 women were managed. Median age was 21 years (range 15–49). The patients were managed for complicated lower trunk, groin, and upper thigh wounds after resection of three pelvic chondrosarcomas as well as two pelvic and two proximal femur osteosarcomas. The modifications included a VRAM flap with lateral and tongue-like extension design of the skin paddle (5 cases) or a delayed extended VRAM flap (2 cases).Results. All flaps showed complete survival and healing with no ischemic events providing stable coverage. All patients were ambulant with good limb functions in terms of walking and gait after adequate rehabilitation, 2 needed support with crutches.Conclusion. The modified VRAM flaps offer reliable reconstructive tools for coverage of complex groin and thigh defects by providing larger well-vascularized soft tissue with acceptable donor site.
Effects of Radix Adenophorae and Cyclosporine A on an OVA‐Induced Murine Model of Asthma by Suppressing to T Cells Activity, Eosinophilia, and Bronchial Hyperresponsiveness
Authors: Roh Seong-Soo , Kim Seung-Hyung , Lee Young-Cheol , Seo Young-Bae
Published: March 2008

The present study is performed to investigate the inhibitory effects of Radix Adenophorae extract (RAE) on ovalbumin‐induced asthma murine model. To study the anti‐inflammatory and antiasthmatic effects of RAE, we examined the development of pulmonary eosinophilic inflammation and inhibitory effects of T cells in murine by RAE and cyclosporine A (CsA). We examined determination of airway hyperresponsiveness, flow cytometric analysis (FACS), enzyme‐linked immunosorbent assay (ELISA), quantitative real time (PCR), hematoxylin‐eosin staining, and Masson trichrome staining in lung tissue, lung weight, total cells, and eosinophil numbers in lung tissue. We demonstrated how RAE suppressed development on inflammation and decreased airway damage.
Effect of Gold Dispersion on the Photocatalytic Activity of Mesoporous Titania for the Vapor‐Phase Oxidation of Acetone
Authors: Awate S. V. , Belhekar A. A. , Bhagwat S. V. , Kumar R. , Gupta N. M.
Published: March 2008

Mesostructured titanium dioxide photocatalyst, having uniform crystallite size (6–12 nm) and average pore diameter of ∼4.2 nm, was synthesized by using a low‐temperature nonsurfactant hydrothermal route, employing tartaric acid as a templating agent. Gold additions from 0.5 to 2 wt% were incorporated, either during the hydrothermal process or by postsynthesis wet impregnation. Compared to the impregnation‐prepared samples, the samples synthesized hydrothermally contained smaller‐size (≤1 nm) gold clusters occluded in the pores of the host matrix. Whereas CO2 and H2O were the main reaction products in UV‐assisted vapor‐phase oxidation of acetone using these catalysts, C2H6 and HCO2CH3 were also produced for higher acetone concentrations in air. The conversion of acetone was found to increase with decrease in the size of both TiO2 and gold particles. In situ IR spectroscopy revealed that titania and gold particles serve as independent adsorption and reaction sites for acetone and oxygen molecules. Acetone molecules adsorb exclusively at TiO2 surface, giving rise to a strongly adsorbed (condensed) state as well as to the formation of formate‐ and methyl formate‐type surface species. Hydroxyl groups at titania surface participate directly in these adsorption steps. Nanosize gold particles, on the other hand, were primarily responsible for the adsorption and activation of oxygen molecules. Mechanistic aspects of the photochemical processes are discussed on the basis of these observations.
Dynamics of Fluid Fuel Reactors in the Presence of Periodic Perturbations
Authors: Dulla S. , Nicolino C.
Published: March 2008

The appearance of perturbations characterized by a periodic time behavior in fluid fuel reactors is connected to the possible precipitation of fissile compounds which are moved within the primary circuit by the fuel motion. In this paper the time-dependent response of a critical fluid fuel system to periodic perturbations is analyzed, solving the full neutronic model and comparing the results with approximate methods, such as point kinetics. A fundamental eigenvalue of the problem is defined, characterizing the trend of divergence of the power. Parametric studies on the reactivity insertion, the fuel velocity and the recirculation time are performed, evidencing the sensitivity of the eigenvalue on typical design parameters. Non-linear calculations in the presence of a negative feedback term are then performed, in order to assess the possibility to control a fluid fuel system when periodic reactivity perturbations are involved.
An Empirical Bayesian Method for Detecting Differentially Expressed Genes Using EST Data
Authors: You Na , Liu Junmei , Mao Chang Xuan
Published: March 2008

Detection of differentially expressed genes from expressed sequence tags (ESTs) data has received much attention. An empirical Bayesian method is introduced in which gene expression patterns are estimated and used to define detection statistics. Significantly differentially expressed genes can be declared given detection statistics. Simulation is done to evaluate the performance of proposed method. Two real applications are studied.
Particle Swarm for Attribute Selection in Bayesian Classification: An Application to Protein Function Prediction
Authors: Correa ElonS. , Freitas AlexA. , Johnson ColinG.
Published: March 2008

The discrete particle swarm optimization (DPSO) algorithm is an
optimization technique which belongs to the fertile paradigm of Swarm Intelligence.
Designed for the task of attribute selection, the DPSO deals with discrete
variables in a straightforward manner. This work empowers the DPSO algorithm
by extending it in two ways. First, it enables the DPSO to select attributes for a
Bayesian network algorithm, which is more sophisticated than the Naive Bayes
classifier previously used by the original DPSO algorithm. Second, it applies the
DPSO to a set of challenging protein functional classification data, involving a
large number of classes to be predicted. The work then compares the performance
of the DPSO algorithm against the performance of a standard Binary PSO
algorithm on the task of selecting attributes on those data sets. The criteria used
for this comparison are (1) maximizing predictive accuracy and (2) finding the
smallest subset of attributes.
Cardiovascular Disease and Risk Factors among Psoriasis Patients in Two US Healthcare Databases, 2001–2002
Authors: Kimball A.B. , Robinson, Jr. D. , Wu Y. , Guzzo C. , Yeilding N. , Paramore C. , Fraeman K. , Bala M.
Published: March 2008

Background: Cardiovascular diseases or risk factors (CVDR) seem to be more common in psoriasis patients than in the general population. Objective: We assessed the relationship of psoriasis with CVDR by analysis of healthcare claims data using a cross-sectional, prevalence-based study design. Patients and Methods: The IMS Health and MarketScan® claims databases were used to identify adults with psoriasis diagnostic codes. Non-psoriasis controls were matched 3:1 based on age, gender, census region and previous medical insurance coverage. Odds ratios evaluated the relative prevalence of CVDR, and Mantel-Haenszel confidence intervals were estimated. Results: CVDR prevalence was generally higher in psoriasis patients than controls in both datasets. Odds ratios for atherosclerosis, congestive heart failure, type 2 diabetes, and peripheral vascular disease were ≧1.20 for psoriasis patients. Elevated disease severity was associated with a higher rate of CVDR, but varied somewhat by dataset and condition. Conclusions: Elevated CVDR rates were found in psoriasis patients compared with controls. This pattern merits further examination.
An Isolation Method for Assessment of Brain Mitochondria Function in Neonatal Mice with Hypoxic-Ischemic Brain Injury
Authors: Caspersen Casper S. , Sosunov Alexander , Utkina-Sosunova Irina , Ratner Veniamin I. , Starkov Anatoly A. , Ten Vadim S.
Published: March 2008

This work was undertaken to develop a method for the isolation of mitochondria from a single cerebral hemisphere in neonatal mice. Mitochondria from the normal mouse brain hemisphere isolated by the proposed method exhibited a good respiratory control ratio of 6.39 ± 0.53 during glutamate-malate-induced phosphorylating respiration. Electron microscopy showed intact mitochondria. The applicability of this method was tested on mitochondria isolated from naïve mice and their littermates subjected to hypoxic-ischemic insult. Hypoxic-ischemic insult prior to reperfusion resulted in a significant (p < 0.01) inhibition of phosphorylating respiration compared to naïve littermates. This was associated with a profound depletion of the ATP content in the ischemic hemisphere. The expression for Mn superoxide dismutase and cytochrome C (markers for the integrity of the mitochondrial matrix and outer membrane) was determined by Western blot to control for mitochondrial integrity and quantity in the compared samples. Thus, we have developed a method for the isolation of the cerebral mitochondria from a single hemisphere adapted to neonatal mice. This method may serve as a valuable tool to study mitochondrial function in a mouse model of immature brain injury. In addition, the suggested method enables us to examine the mitochondrial functional phenotype in immature mice with a targeted genetic alteration.
Isolation and Characterization of Porcine Adipose Tissue-Derived Adult Stem Cells
Authors: Williams Kellie J. , Picou Alicia A. , Kish Sharon L. , Giraldo Angelica M. , Godke Robert A. , Bondioli Kenneth R.
Published: March 2008

Background: Stem cell characteristics such as self-renewal, differentiation and expression of CD34 and CD44 stem cell markers have not been identified in porcine adipose tissue-derived adult stem (ADAS) cells. The objective of this study was to develop a protocol for the isolation and culture of porcine adipose tissue-derived cells and to determine stem cell-like characteristics. Methods: Primary cultures were established and cell cultures were maintained. Cloning capacity was determined using a ring cloning procedure. Primary cultures and clones were differentiated and stained for multiple differentiated phenotypes. CD34 and CD44 messenger ribonucleic acid (mRNA) was isolated and reverse transcriptase polymerase chain reaction was used to compare expression profiles. Results: An average of 2,700,000 nucleated cells/ml was isolated; 26% were adherent, and cells completed a cell cycle approximately every 3.3 days. Ring cloning identified 19 colonies. Primary cultures and clones were determined to differentiate along osteogenic, adipogenic and chondrogenic tissue lineages. The mRNA expression profiles showed CD34 expression was higher for undifferentiated ADAS cells versus differentiated cell types and the CD34 expression level was lower than that of CD44 among differentiated cells. Conclusion: Improved culture conditions and defined cellular characteristics of these porcine ADAS cells have been identified. Porcine ADAS can self-renew, can differentiate into multiple tissue lineages and they express CD34.
Expression Patterns of Neurotrophins and Neurotrophin Receptors in Articular Chondrocytes and Inflammatory Infiltrates in Knee Joint Arthritis
Authors: Grimsholm Ola , Guo Yongzhi , Ny Tor , Forsgren Sture
Published: March 2008

Background: It is likely that neurotrophins (NTs) are of great importance for the articular cartilage and the inflammation process in arthritis. Methods: The immunohistochemical expression of the NTs nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) and the associated receptors p75, TrkA and TrkB was examined in the knee joint of arthritic and healthy mice. Results: Immunoreactions for NGF and BDNF were detected in cells and nerve fiber varicosities in the inflammatory infiltrates of the synovial tissue of arthritic joints but not in synovial tissue of controls. p75-immunoreactive nerve fiber-like strands were detected in inflammatory infiltrates. Immunostaining for NGF, BDNF, p75, TrkA and TrkB was noted in articular chondrocytes. There was a statistically significant decrease in reactions for NGF (p < 0.001), TrkA (p = 0.001) and p75 (p < 0.001) in articular chondrocytes in joints exhibiting severe arthritis. Conclusion: The findings show that an NT system develops in inflammatory infiltrates of the synovial tissue. Furthermore, most interestingly, autocrine/paracrine effects appear to exist concerning NTs for the articular chondrocytes. The downregulated expression of NGF and NT receptors in articular chondrocytes in arthritis is a new aspect concerning the involvement of NTs in cartilage.