bluuebunny/crossref_metadata_2025 huggingface dataset:
Gonadal hormone-dependent and -independent regulation of immune function by photoperiod in Siberian hamsters
Authors: Prendergast Brian J. , Baillie Scott R. , Dhabhar Firdaus S.
Published: November 2007

Siberian hamsters ( Phodopus sungorus) exhibit changes in reproductive and immune function in response to seasonal variations in day length. Exposure to short days induces gonadal regression and inhibits testosterone secretion. In parallel, short days enhance immune function: increasing leukocyte numbers and attenuating cytokine and behavioral responses to infection. We examined whether photoperiodic changes in leukocyte phenotypes and sickness behaviors are dependent on concurrent photoperiodic changes in gonadal function. Male hamsters were gonadectomized or sham-gonadectomized and either exposed to short days (9 h light/day; SD) or kept in their natal long-day (15 h light/day; LD) photoperiod for 10–13 wk. Blood samples were obtained for leukocyte enumeration, and hamsters were challenged with bacterial LPS, which induced behavioral (anorexia, reductions in nest building) and somatic (weight loss) sickness responses. Among gonad-intact hamsters, exposure to SD increased total and CD62L+ lymphocytes and CD3+ T lymphocytes in blood and significantly attenuated LPS-induced sickness responses. Independent of photoperiod, castration alone increased total and CD62L+ lymphocyte and CD3+ T lymphocyte numbers and attenuated somatic and anorexic sickness responses. Among castrated hamsters, SD exposure increased lymphocyte numbers and suppressed sickness behaviors. In castrated hamsters, the magnitude of most immunological effects of SD were diminished relative to those evident in gonad-intact hamsters. The SD phenotype in several measures of immunity can be instated via elimination of gonadal hormones alone; however, photoperiodic effects on immune function persist even in castrated hamsters. Thus, photoperiod affects the immune system and neural-immune interactions underlying sickness behaviors via gonadal hormone-dependent and -independent mechanisms.
Prolonged treadmill training increases HSP70 in skeletal muscle but does not affect age-related functional deficits
Authors: Kayani Anna C. , Close Graeme L. , Jackson Malcolm J. , McArdle Anne
Published: November 2007

Skeletal muscle atrophy and weakness are major causes of frailty in the elderly. Functional deficits in muscles of old humans and rodents are associated with attenuated production of heat shock proteins (HSPs) after exercise, and transgenic overexpression of HSP70 reverses this functional decline. We hypothesized that training would increase HSP70 content of muscle in adult and old wild-type mice and that this would protect against the development of age-related functional deficits. A 10-wk treadmill training protocol at 15 m/min, for 15 min, 3 days/wk resulted in a significant increase in HSP70 content of muscles of adult mice. Muscles of old untrained mice demonstrated a significant increase in HSP70 protein content and a reduction in HSP70 mRNA content compared with adult untrained mice. Training for 12 mo starting at age 12–14 mo old or for 10 wk starting from age 24 mo old resulted in modification of HSP70 protein and mRNA content to levels of adult mice. Training did not change force generation of extensor digitorum longus muscles of old mice or improve recovery after damaging contractions. The twofold increase in HSP70 content in muscles of adult mice after training may have not been sufficient to provide protection in this instance.
Anti-LOX-1 therapy in rats with diabetes and dyslipidemia: ablation of renal vascular and epithelial manifestations
Authors: Dominguez Jesus H. , Mehta Jawahar L. , Li Dayuan , Wu Pengfei , Kelly Katherine J. , Packer C. Subah , Temm Constance , Goss Erin , Cheng Liang , Zhang Shaobo , Patterson Carolyn E. , Hawes John W. , Peterson Richard
Published: November 2007

LOX-1 is a multifunctional membrane receptor that binds and internalizes oxidized LDL (oxLDL). We tested the hypothesis that blockade of LOX-1 with an anti-LOX-1 antibody limits nephropathy in male rats with diabetes and dyslipidemia (ZS rats; F1hybrid product of Zucker fatty diabetic rats and spontaneous hypertensive heart failure rats). Lean ZS rats were controls, while untreated obese ZS (OM), ZS obese rats injected with nonspecific rabbit IgG (OM-IgG; 2 μg intravenous injection given weekly), and obese ZS rats given anti-LOX-1 rabbit antibody (OM-Ab; 2 μg intravenous injection given weekly) were the experimental groups. The rats were treated from 6 to 21 wk of age. All obese groups had severe dyslipidemia and hyperglycemia. Kidneys of obese rats expressed LOX-1 in capillaries and tubules, were larger, accumulated lipid, had intense oxidative stress, leukocyte infiltration, depressed mitochondrial enzyme level and function, and peritubular fibrosis (all P < 0.05 vs. lean ZS rats). Injections with LOX-1 antibody limited these abnormalities ( P < 0.01 vs. data in OM or OM-lgG rats). In vitro, renal epithelial LOX-1 expression was verified in a cultured proximal tubule cell line. Our study indicates that anti-LOX-1 (vascular and epithelial) therapy may effectively reverse critical pathogenic elements of nephropathy in diabetes and dyslipidemia.
Inhibitory effect of interleukin-1β on angiotensin II-induced connective tissue growth factor and type IV collagen production in cultured mesangial cells
Authors: Sánchez-López Elsa , Rodriguez-Vita Juan , Cartier Cecile , Rupérez Monica , Esteban Vanesa , Carvajal Gisselle , Rodrígues-Díez Raquel , Plaza Juan José , Egido Jesús , Ruiz-Ortega Marta
Published: November 2007

Connective tissue growth factor (CTGF) is overexpressed in kidney diseases associated with extracellular matrix accumulation. Angiotensin II (ANG II) participates in renal fibrosis by the upregulation of growth factors, including CTGF, and extracellular matrix proteins, such as type IV collagen. During renal injury, ANG II and the macrophage-produced cytokine interleukin-1β (IL-1β) may be present simultaneously in the glomerular environment. However, there are no studies about the interaction between ANG II and IL-1β in renal fibrosis. For this reason, in cultured mesangial cells (MC), we investigated whether IL-1β could regulate ANG II-mediated collagen accumulation and the mechanisms underlying this process. In MC, CTGF is a downstream mediator of type IV collagen production induced by ANG II. IL-1β did not increase the production of CTGF and type IV collagen but significantly inhibited ANG II-induced CTGF and type IV collagen overexpression. Moreover, IL-1β also inhibited type IV collagen upregulation caused by exogenous recombinant CTGF. Matrix metalloproteinase-9 (MMP-9) is the main enzyme involved in type IV collagen degradation. In MC, coincubation of IL-1β and ANG II caused a synergistic increase in MMP-9 gene expression and activity, associated with type IV collagen inhibition. The described IL-1β effects were dependent on activation of ERK/MAPK but independent p38-MAPK, JNK, phosphatidylinositol 3-kinase/Akt, and Rho-associated kinase pathways. In summary, these data indicate that IL-1β inhibited ANG II-mediated type IV collagen production, via CTGF downregulation, and increased type IV collagen degradation, through MMP-9 upregulation. Our in vitro data show that the proinflammatory cytokine IL-1β abrogates ANG II-induced CTGF production, describing antagonistic activities of proinflammatory cytokines on ANG II actions.
Purinergic receptors contribute to early mesangial cell transformation and renal vessel hypertrophy during angiotensin II-induced hypertension
Authors: Graciano Miguel L. , Nishiyama Akira , Jackson Keith , Seth Dale M. , Ortiz Rudy M. , Prieto-Carrasquero Minolfa C. , Kobori Hiroyuki , Navar L. Gabriel
Published: November 2007

Chronic ANG II infusions lead to increases in intrarenal ANG II levels, hypertension, and tissue injury. Increased blood pressure also elicits increases in renal interstitial fluid (RIF) ATP concentrations that stimulate cell proliferation. We evaluated the contribution of purinergic receptor activation to ANG II-induced renal injury in rats by treating with clopidogrel, a P2Y12 receptor blocker, or with PPADS, a nonselective P2 receptor blocker. α-Actin expression in mesangial cells, afferent arteriolar wall thickness (AAWT), cortical cell proliferation, and macrophage infiltration were used as early markers of renal injury. Clopidogrel and PPADS did not alter blood pressure, renin or kidney ANG II content. α-Actin expression increased from control of 0.6 ± 0.4% of mesangial area to 6.3 ± 1.9% in ANG II-infused rats and this response was prevented by clopidogrel (0.4 ± 0.2%) and PPADS. The increase in AAWT from 4.7 ± 0.1 to 6.0 ± 0.1 mm in ANG II rats was also prevented by clopidogrel (4.8 ± 0.1 mm) and PPADS. ANG II infusion led to interstitial macrophage infiltration (105 ± 16 vs. 62 ± 4 cell/mm2) and tubular proliferation (71 ± 15 vs. 20 ± 4 cell/mm2) and these effects were prevented by clopidogrel (52 ± 4 and 36 ± 3 cell/mm2) and PPADS. RIF ATP levels were higher in ANG II-infused rats than in control rats (11.8 ± 1.9 vs. 5.6 ± 0.6 nmol/l, P < 0.05). The results suggest that activation of vascular and glomerular purinergic P2 receptors may contribute to the mesangial cell transformation, renal inflammation, and vascular hypertrophy observed in ANG II-dependent hypertension.
Tuberin regulates the DNA repair enzyme OGG1
Authors: Habib Samy L. , Riley Daniel J. , Mahimainathan Lenin , Bhandari Basant , Choudhury Goutam Ghosh , Abboud Hanna E.
Published: November 2007

The tuberous sclerosis complex (TSC) is caused by defects in one of two tumor suppressor genes, TSC-1 or TSC-2. The TSC-2 gene encodes tuberin, a protein involved in the pathogenesis of kidney tumors, both angiomyolipomas and renal cell carcinomas. We investigated a potential role for tuberin in regulating a key DNA repair pathway. Downregulation of tuberin in human renal epithelial cells using siRNA resulted in a marked decrease in the abundance of the 8-oxoG-DNA glycosylase (OGG1). Mouse embryonic fibroblasts deficient in tuberin ( TSC2−/− and TSC2+/−) also had markedly decreased OGG1 mRNA and protein expression, as well as undetectable OGG1 activity accompanied by accumulation of 8-oxodG. Gel shift analyses and chromatin immunoprecipatation identified the transcription factor NF-YA as a regulator of OGG1 activity. The binding of NF-YA to the OGG1 promoter was significantly reduced in TSC2−/− compared with TSC2+/+ cells. Introduction of TSC2 cDNA into the tuberin-deficient cells restored NF-YA and OGG1 expression. Transcriptional activity of the OGG1 promoter was also decreased in tuberin-null cells. In addition, mutation of both CAAT boxes, the sites to which NF-YA binds, completely inhibits OGG1 promoter activity. These data provide the first evidence that tuberin regulates a specific DNA repair enzyme, OGG1. This regulation may be important in the pathogenesis of kidney tumors in patients with TSC.
Gray matter blood flow change is unevenly distributed during moderate isocapnic hypoxia in humans
Authors: Binks Andrew P. , Cunningham Vincent J. , Adams Lewis , Banzett Robert B.
Published: November 2007

Hypoxia increases cerebral blood flow (CBF), but it is unknown whether this increase is uniform across all brain regions. We used H215O positron emission tomography imaging to measure absolute blood flow in 50 regions of interest across the human brain ( n = 5) during normoxia and moderate hypoxia. Pco2 was kept constant (∼44 Torr) throughout the study to avoid decreases in CBF associated with the hypocapnia that normally occurs with hypoxia. Breathing was controlled by mechanical ventilation. During hypoxia (inspired Po2 = 70 Torr), mean end-tidal Po2 fell to 45 ± 6.3 Torr (means ± SD). Mean global CBF increased from normoxic levels of 0.39 ± 0.13 to 0.45 ± 0.13 ml/g during hypoxia. Increases in regional CBF were not uniform and ranged from 9.9 ± 8.6% in the occipital lobe to 28.9 ± 10.3% in the nucleus accumbens. Regions of interest that were better perfused during normoxia generally showed a greater regional CBF response. Phylogenetically older regions of the brain tended to show larger vascular responses to hypoxia than evolutionary younger regions, e.g., the putamen, brain stem, thalamus, caudate nucleus, nucleus accumbens, and pallidum received greater than average increases in blood flow, while cortical regions generally received below average increases. The heterogeneous blood flow distribution during hypoxia may serve to protect regions of the brain with essential homeostatic roles. This may be relevant to conditions such as altitude, breath-hold diving, and obstructive sleep apnea, and may have implications for functional brain imaging studies that involve hypoxia.
Lung function in adults with stable but severe asthma: air trapping and incomplete reversal of obstruction with bronchodilation
Authors: Sorkness Ronald L. , Bleecker Eugene R. , Busse William W. , Calhoun William J. , Castro Mario , Chung Kian Fan , Curran-Everett Douglas , Erzurum Serpil C. , Gaston Benjamin M. , Israel Elliot , Jarjour Nizar N. , Moore Wendy C. , Peters Stephen P. , Teague W. Gerald , Wenzel, Sally E.
Published: November 2007

Five to ten percent of asthma cases are poorly controlled chronically and refractory to treatment, and these severe cases account for disproportionate asthma-associated morbidity, mortality, and health care utilization. While persons with severe asthma tend to have more airway obstruction, it is not known whether they represent the severe tail of a unimodal asthma population, or a severe asthma phenotype. We hypothesized that severe asthma has a characteristic physiology of airway obstruction, and we evaluated spirometry, lung volumes, and reversibility during a stable interval in 287 severe and 382 nonsevere asthma subjects from the National Heart, Lung, and Blood Institute Severe Asthma Research Program. We partitioned airway obstruction into components of air trapping [indicated by forced vital capacity (FVC)] and airflow limitation [indicated by forced expiratory volume in 1 s (FEV1)/FVC]. Severe asthma had prominent air trapping, evident as reduced FVC over the entire range of FEV1/FVC. This pattern was confirmed with measures of residual lung volume/total lung capacity (TLC) in a subgroup. In contrast, nonsevere asthma did not exhibit prominent air trapping, even at FEV1/FVC <75% predicted. Air trapping also was associated with increases in TLC and functional reserve capacity. After maximal bronchodilation, FEV1 reversed similarly from baseline in severe and nonsevere asthma, but the severe asthma classification was an independent predictor of residual reduction in FEV1 after maximal bronchodilation. An increase in FVC accounted for most of the reversal of FEV1 when baseline FEV1 was <60% predicted. We conclude that air trapping is a characteristic feature of the severe asthma population, suggesting that there is a pathological process associated with severe asthma that makes airways more vulnerable to this component.
Mechanisms Underlying Dedepression of Synaptic NMDA Receptors in the Hippocampus
Authors: Morishita Wade , Malenka Robert C.
Published: November 2007

N-Methyl-d-aspartate receptor (NMDAR)–mediated synaptic responses in hippocampal CA1 pyramidal cells are depressed during NMDAR-dependent long-term depression (LTD) due to mechanisms, in part, distinct from those underlying LTD of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)–mediated synaptic responses. The mechanisms underlying dedepression of synaptic NMDARs, however, are not known. We find that dedepression of NMDAR-mediated synaptic responses in the CA1 region of the rat hippocampus is input specific and does not require synaptic stimulation to be maintained. The induction of dedepression does not require activation of metabotropic glutamate receptors, L-type Ca2+ channels, or release of Ca2+ from intracellular stores. It does, however, rely on activation of NMDARs. In contrast to the dedepression of AMPAR-mediated synaptic responses, dedepression of NMDAR-mediated synaptic responses does not depend on activation of calcium/calmodulin-dependent protein kinase II, protein kinase C, cAMP-dependent protein kinase, or Src kinases. However, dedepression of synaptic NMDARs is significantly impaired by inhibitors of mitogen-activated protein kinase signaling. Specifically, inhibitors of extracellular signal-regulated kinase 1/2 prevented normal dedepression of synaptic NMDARs by a mechanism that did not require protein synthesis. These results provide further evidence that synaptic NMDARs can be bidirectionally modified by activity but by mechanisms distinct from those responsible for the activity-dependent, bidirectional modulation of synaptic AMPARs.
A New Jumping Genes Paradigm for an E-Shaped Folded Patch Feed Antenna Design
Authors: Yeung S. H. , Man K. F.
Published: November 2007

A novel evolutionary computing algorithm, namely, jumping genes evolutionary algorithm
(JGEA) is used for the optimization of antenna designs. This scheme incorporates with a multiobjective
strategy that enables the gene mobility within the same chromosome, or even to a different chromosome.
This type of horizontal gene movement causes the genes to find the suitable locations to achieve the
necessary building blocks in such a way that the quality of nondominated solutions and/or the Pareto-optimal
solutions can be enhanced. This new scheme is robust and provides outputs in speed and accuracy.
It also generates a range of widespread extreme solutions. The design of an E-shaped patch antenna was
adopted for the purpose of design demonstration. An antenna structure with 91% impedance bandwidth
for a frequency range of 3.6–9.6 GHz was selected amongst the nondominated solutions set for the
hardware fabrication. Its measured performances both for impedance bandwidth and frequency range
were in good agreement with the simulated solution. The cross-polarized field was found to be small in
comparison, and the copolarized field can sustain the broadside radiation pattern over the frequency band.
This methodology of optimization can be of an alternative approach for antenna design.
Perron-Type Criterion for Linear Difference Equations with Distributed Delay
Authors: Alzabut Jehad O. , Abdeljawad Thabet
Published: November 2007

It is shown that if a linear difference equation with distributed delay of the formΔx(n)=∑k=−d0Δkζ(n+1,k−1)x(n+k−1),n≥1, satisfies a Perron condition then its trivial solution is uniformly asymptotically stable.
Solution of Cauchy-Type Singular Integral Equations of the First Kind with Zeros of Jacobi Polynomials as Interpolation Nodes
Authors: Okecha G. E.
Published: November 2007

Of concern in this paper is the numerical solution of Cauchy-type singular integral equations of the first kind at a discrete set of points. A quadrature rule based on Lagrangian interpolation, with the zeros of Jacobi polynomials as nodes, is developed to solve these equations. The problem is reduced to a system of linear algebraic equations. A theoretical convergence result for the approximation is provided. A few numerical results are given to illustrate and validate the power of the method developed. Our method is more accurate than some earlier methods developed to tackle this problem.
Characterizations of Polystyrene-Based Hybrid Particles Containing Hydrophobic Mg(OH)2Powder and Composites Fabricated by Employing Resultant Hybrid Particles
Authors: Kimura Shuichi , Hyodo Takeo , Shimizu Yasuhiro , Egashira Makoto
Published: November 2007

Polystyrene (PS)-based hybrid particles containing a large amount of Mg(OH)2powder treated with methylhydrogen polysiloxane (MHS) were fabricated by a bulk and subsequent suspension two-step polymerization method. All the particles fabricated showed spherical shape and their particle sizes were about 500 μm, irrespective of the additive amount of the Mg(OH)2powder modified with MHS (ST-1). The actual content of ST-1 powder incorporated inside each kind of hybrid particle was almost the same as that in the raw mixture, and agglomeration of ST-1 powder was hardly observed inside the hybrid particles. The compressive strength of the hybrid particles remained almost unchanged, even when the ST-1 powder content increased from 10 to 50 phr. Furthermore, a composite fabricated by employing the hybrid particles achieved homogenous distribution of ST-1 powder and showed a higher oxygen index than that of a composite fabricated by directly mixing of PS pellets and ST-1 powder.
On SolvingLq-Penalized Regressions
Authors: Wu Tracy Zhou , Chu Yingyi , Yu Yan
Published: November 2007

Lq-penalized regression arises in multidimensional statistical modelling where all or part of the regression coefficients are penalized to achieve both accuracy and parsimony of statistical models. There is often substantial computational difficulty except for the quadratic penalty case. The difficulty is partly due to the nonsmoothness of the objective function inherited from the use of the absolute value. We propose a new solution method for the generalLq-penalized regression problem based on space transformation and thus efficient optimization algorithms. The new method has immediate applications in statistics, notably in penalized spline smoothing problems. In particular, the LASSO problem is shown to be polynomial time solvable. Numerical studies show promise of our approach.
Enhanced P2P Services Providing Multimedia Content
Authors: Ardizzone E. , Gatani L. , La Cascia M. , Lo Re G. , Ortolani M.
Published: November 2007

The retrieval facilities of most Peer-to-Peer (P2P) systems are limited to queries based on unique identifiers or small sets of keywords. Unfortunately, this approach is very inadequate and inefficient when a huge amount of multimedia resources is shared. To address this major limitation, we propose an original image and video sharing system, in which a user is able to interactively search interesting resources by means of content-based image and video retrieval techniques. In order to limit the network traffic load, maximizing the usefulness of each peer contacted in the query process, we also propose the adoption of an adaptive overlay routing algorithm, exploiting compact representations of the multimedia resources shared by each peer. Experimental results confirm the validity of the proposed approach, that is capable of dynamically adapting the network topology to peer interests, on the basis of query interactions among users.
Some Remarks on Perturbation Classes of Semi-Fredholm and Fredholm Operators
Authors: Dehici Abdelkader , Saoudi Khaled
Published: November 2007

We show the existence of Banach spacesX,Ysuch that the set of strictly singular operators𝒮(X,Y)(resp., the set of strictly cosingular operators𝒞𝒮(X,Y))would be strictly included inℱ+(X,Y)(resp.,ℱ−(X,Y))for the nonempty class of closed densely defined upper semi-Fredholm operatorsΦ+(X,Y)(resp., for the nonempty class of closed densely defined lower semi-Fredholm operatorsΦ−(X,Y)).
Stabilizability and Motion Tracking Conditions for Mechanical Nonholonomic Control Systems
Authors: Jarzębowska Elżbieta
Published: November 2007

This paper addresses formulation of stabilizability and motion tracking conditions for mechanical systems from the point of view of constraints put on them. We present a new classification of constraints, which includes nonholonomic constraints that arise in both mechanics and control. Based on our classification we develop kinematic and dynamic control models of systems subjected to these constraints. We demonstrate that a property of being a “hard-to-control” nonholonomic system may not be related to the nature of the constraints. It may result from the formulation of control objectives for a system. We examine two control objectives which are stabilization to the target equilibrium by a continuous static state feedback control and motion tracking. Theory is illustrated with examples of control objective formulations for systems with constraints of various types.
CRALBP is a Highly Prevalent Autoantigen for Human Autoimmune Uveitis
Authors: Deeg Cornelia A. , Raith Albert J. , Amann Barbara , Crabb John W. , Thurau Stephan R. , Hauck Stefanie M. , Ueffing Marius , Wildner Gerhild , Stangassinger Manfred
Published: November 2007

Cellular retinaldehyde binding protein (CRALBP) is an autoantigen in spontaneous equine recurrent uveitis. In order to test whether CRALBP contributes to human autoimmune uveitis, the specificity of antibodies from human uveitis patient's sera was first evaluated in two-dimensional (2D) Western blot analysis. Subsequent identification of the immunoreactive proteins by mass spectrometry resulted in the identification of CRALBP as a putative autoantigen. Additionally, sera from human uveitis and control patients were by Western blot using purified human recombinant CRALBP. Anti-CRALBP autoantibodies occur more frequently (P<.01) in human uveitis patients than in normal controls. Thirty out of 56 tested uveitis patient's sera contained autoantibodies reactive against CRALBP, compared to only four out of 23 normal control subjects. The presence of CRALBP autoantibodies in 54% of tested uveitis patients supports CRALBP as a possible autoantigen in human autoimmune uveitis.
Contra-ω-Continuous and Almost Contra-ω-Continuous
Authors: Al-Omari Ahmad , Noorani Mohd Salmi Md
Published: November 2007

The notion of contra continuous functions was introduced and investigated by Dontchev. In this paper, we apply the notion ofω-open sets in topological space to present and study a new class of called almost contraω-continuous functions as a new generalization of contra continuity.
Enhanced Gain Microstrip Patches Operating on Higher Order Modes
Authors: Polivka Milan , Holub Alois
Published: November 2007

Novel topologies of rectangular microstrip patches providing broadside radiated one point fed radiators with enhanced gain
are compared. The principle of the gain enhancement is based on an extension of a source area. Dominant in-phase current
distribution on the patch is maintained by using higher order mode and geometrical modification of the patch topology. That is
achieved by introducing suitable perturbation elements in the shape of slots and notches. Two principal patch topologies
operating on TM21 and TM03 modes are described. A comparison of simulated and measured properties of realized prototypes
at 10 GHz band are presented. The results show that gain 12.3 dBi of single patch can be reached.
Marked Continuous-Time Markov Chain Modelling of Burst Behaviour for Single Ion Channels
Authors: Ball Frank G. , Milne Robin K. , Yeo Geoffrey F.
Published: November 2007

Patch clamp recordings from ion channels often show bursting behaviour, that is, periods of repetitive activity, which are noticeably separated from each other by periods of inactivity. A number of authors have obtained results for important properties of theoretical and empirical bursts when channel gating is modelled by
a continuous-time Markov chain with a finite-state space. We show how the use of marked continuous-time Markov chains can simplify the derivation of (i) the distributions of several burst properties, including the total open time, the total charge transfer, and the number of openings in a burst, and (ii) the form of these distributions when the underlying gating process is time reversible and in equilibrium.
Simplified LLRs for the Decoding of Single Parity Check Turbo Product Codes Transmitted Using 16QAM
Authors: Arar Maher , D'Amours Claude , Yongacoglu Abbas
Published: November 2007

Iterative soft-decision decoding algorithms require channel log-likelihood ratios (LLRs) which, when using 16QAM modulation, require intensive computations to be obtained. Therefore, we derive four simple approximate LLR expressions. When using the maximum a posteriori probability algorithm for decoding single parity check turbo product codes (SPC/TPCs), these LLRs can be simplified even further. We show through computer simulations that the bit-error-rate performance of(8,7)2and(8,7)3SPC/TPCs, transmitted using 16QAM and decoded using the maximum a posteriori algorithm with our simplified LLRs, is nearly identical to the one achieved by using the exact LLRs.
Strong Convergence of Cesàro Mean Iterations for Nonexpansive Nonself-Mappings in Banach Spaces
Authors: Wangkeeree Rabian
Published: November 2007

Let "Equation missing" be a real uniformly convex Banach space which admits a weakly sequentially continuous duality mapping from "Equation missing" to "Equation missing", "Equation missing" a nonempty closed convex subset of "Equation missing" which is also a sunny nonexpansive retract of "Equation missing", and "Equation missing" a non-expansive nonself-mapping with "Equation missing". In this paper, we study the strong convergence of two sequences generated by "Equation missing" and "Equation missing" for all "Equation missing", where "Equation missing", "Equation missing" is a real sequence in an interval "Equation missing", and "Equation missing" is a sunny non-expansive retraction of "Equation missing" onto "Equation missing". We prove that "Equation missing" and "Equation missing" converge strongly to "Equation missing" and "Equation missing", respectively, as "Equation missing", where "Equation missing" is a sunny non-expansive retraction of "Equation missing" onto "Equation missing". The results presented in this paper generalize, extend, and improve the corresponding results of Matsushita and Kuroiwa and many others.
Aerodynamically Assisted Jet Fabrication and Deposition of Composite Scaffolds via Concentric Needles
Authors: Arumuganathar S. , Jayasinghe S. N.
Published: November 2007

Recent interests in process methodologies possessing the ability for forming scaffolds have gained a great deal of scientific attention. Essentially this has resulted from the realization that these constructs have much utility in the life sciences. In this letter, we elucidate a novel and versatile scaffold process fabrication methodology with a concentric jetting process that shows tremendous possibilities for forming stable composite scaffolds. Our studies combine a specially formulated medical grade PDMS (polydimethylsiloxane) medium together with this concentric jetting process demonstrating significant possibilities for controlled composite scaffold formation and deposition. Hence the results presented elucidate promising opportunities for using these scaffolds in the biomedical areas of research.
Theoretical Study of Sequence Selectivity and Preferred Binding Mode of Psoralen with DNA
Authors: Saenz-Méndez Patricia , Guedes Rita C. , dos Santos Daniel J. V. A. , Eriksson Leif A.
Published: November 2007

Psoralen interaction with two models of DNA was investigated using molecular mechanics and molecular dynamics methods. Calculated energies of minor groove binding and intercalation were compared in order to define a preferred binding mode for the ligand. We found that both binding modes are possible, explaining the low efficiency for monoadduct formation from intercalated ligands. A comparison between the interaction energy for intercalation between different base pairs suggests that the observed sequence selectivity is due to favorable intercalation in 5′-TpA in (AT)n sequences.
Far-Field Focus and Dispersionless Anticrossing Bands in Two-Dimensional Photonic Crystals
Authors: Chen Xiaoshuang , Zhou Renlong , Zeng Yong , Chen Hongbo , Lu Wei
Published: November 2007

We review the simulation work for the far-field focus and dispersionless anticrossing bands in two-dimensional (2D) photonic crystals. In a two-dimensional photonic-crystal-based concave lens, the far-field focus of a plane wave
is given by the distance between the focusing point and the lens. Strong and good-quality far-field focusing of a transmitted
wave, explicitly following the well-known wave-beam negative refraction law, can be achieved. The spatial frequency
information of the Bloch mode in multiple Brillouin zones (BZs) is investigated in order to indicate the wave propagation in
two different regions. When considering the photonic transmission in a 2D photonic crystal composed of a negative
phase-velocity medium (NPVM), it is shown that the dispersionless anticrossing bands are generated by the couplings
among the localized surface polaritons of the NPVM rods. The photonic band structures of the NPVM photonic crystals are
characterized by a topographical continuous dispersion relationship accompanied by many anticrossing bands.
Low-Power Built-In Self-Test Techniques for Embedded SRAMs
Authors: Lu Shyue-Kung , Hsiao Yuang-Cheng , Liu Chia-Hsiu , Yang Chun-Lin
Published: November 2007

The severity of power consumption during parallel BIST of embedded memory
cores is growing significantly. In order to alleviate this problem, a row bank-based precharge
technique based on the divided wordline (DWL) architecture is proposed for low-power testing of embedded
SRAMs. The memory cell array is first divided into row banks. The effectiveness of the row
bank-based precharge technique is due to the predictable address sequence during test. In low-power test
mode, instead of precharging the entire memory array, only the current accessed row bank is
precharged. This will result in significant power saving for the precharge circuitry. The precharge power
can be reduced to 1/b of that of the traditional precharge techniques, where b denotes the number of row banks in the memory array. With simple transmission
gates and inverters, the modified precharge control circuitry was also designed. The hardware
overhead for implementing the low-power technique is almost negligible. Moreover, the corresponding
BIST design to implement the low-power technique is almost the same as the conventional BIST
designs. It is also notable that the inherent low-power characteristics of the DWL architecture can
be preserved. According to experimental results, 48.9% power reduction can be achieved for
a 256 × 256 bit-oriented SRAM. The memory is divided into 8 row banks. Moreover, if the number of
row banks increases, the power saving will also increase.
A Paradox in a Queueing Network with State-Dependent Routing and Loss
Authors: Ziedins Ilze
Published: November 2007

Consider a network of parallel finite tandem queues with two stages, where each arrival attempts to
minimize its own cost due to loss. It is known that the user optimal and asymptotic system optimal policies
may differ—we give examples showing that they may differ for finite systems and that as the service
rate is increased at the second stage the user optimal policy may change in such a way that the total expected
cost due to loss increases.
Integrated Balanced BPSK Modulator for Millimeter Wave Systems
Authors: Mittal Ashok , De Asok
Published: November 2007

This paper details the design of integrated balanced PSK modulator using finline coplanar line hybrid junction. The PSK signal output is in suspended stripline with incident wave carrier in finline. Schottky barrier Diode MA4E2037 has been used for modulation. The balanced configuration offers high isolation between the carrier input port and the modulated carrier output port and thus the pulse width variations and amplitude deviations are suppressed. An insertion loss imbalance of±1.5 dB with an average loss of 2 dB in the two switching states has been achieved over 38.9 to 40 GHz. The phase imbalance is±10 degrees with phase switching from 180 to 199 degrees As the PSK output signal is in suspended stripline, two BPSK modulators can be easily combined together to work as QPSK modulator.
Jump Telegraph Processes and Financial Markets with Memory
Authors: Ratanov Nikita
Published: November 2007

The paper develops a new class of financial market models. These models are based on generalized telegraph processes with alternating velocities and jumps occurring at switching velocities. The model under consideration is arbitrage-free and complete if the directions of jumps in stock prices are in a certain correspondence with their velocity and with the behaviour of the interest rate. A risk-neutral measure and arbitrage-free formulae for a standard call option are constructed. This model has some features of models with memory, but it is more simple.
Lipopolysaccharide Binding Protein and sCD14 are Not Produced as Acute Phase Proteins in Cardiac Surgery
Authors: Kudlova Manuela , Kunes Pavel , Kolackova Martina , Lonsky Vladimir , Mandak Jiri , Andrys Ctirad , Jankovicova Karolina , Krejsek Jan
Published: November 2007

Objectives. The changes in the serum levels of lipopolysaccharide binding protein (LBP) and sCD14 during cardiac surgery were followed in this study.Design. Thirty-four patients, 17 in each group, were randomly assigned to coronary artery bypass grafting surgery performed either with (“on-pump”) or without (“off-pump”) cardiopulmonary bypass. LBP and sCD14 were evaluated by ELISA.Results. The serum levels of LBP were gradually increased from the 1st postoperative day and reached their maximum on the 3rd postoperative day in both “on-pump” and “off-pump” patients (30.33±9.96μg/mL;37.99±16.58μg/mL), respectively. There were no significant differences between “on-pump” and “off-pump” patients regarding LBP. The significantly increased levels of sCD14 from the 1st up to the 7th postoperative day in both “on-pump” and “off-pump” patients were found with no significant differences between these groups. No correlations between LBP and sCD14 and IL-6, CRP and long pentraxin PTX3 levels were found.Conclusions. The levels of LBP and sCD14 are elevated in cardiac surgical patients being similar in both groups. These molecules are not produced as acute phase proteins in these patients.
Ultralight-Weight Cellulose Aerogels from NBnMO-Stabilized Lyocell Dopes
Authors: Liebner Falk , Potthast Antje , Rosenau Thomas , Haimer Emmerich , Wendland Martin
Published: November 2007

Cellulose aerogels are intriguing new materials produced by supercritical drying of regenerated cellulose obtained by solvent exchange of solid Lyocell moldings. FromN-methylmorpholine-N-oxide solutions with cellulose contents between 1 and 12%, dimensionally stable cellulose bodies are produced, in which the solution structure of the cellulose is largely preserved and transferred into the solid state. The specific density and surface of the obtained aerogels range from 0.05 to 0.26 g/cm3and from 172 to 284m2/g, respectively, depending on the cellulose content of the Lyocell dopes and regeneration procedure. A reliable extraction and drying procedure using supercritical carbon dioxide, the advantageous use of NBnMO as stabilizer for the Lyocell dopes, and selected physical properties of the materials is communicated.
Improved Diagnostics Using Polarization Imaging and Artificial Neural Networks
Authors: Xuan Jianhua , Klimach Uwe , Zhao Hongzhi , Chen Qiushui , Zou Yingyin , Wang Yue
Published: November 2007

In recent years, there has been an increasing interest in studying the propagation of polarized light in biological cells and tissues. This paper presents a novel approach to cell or tissue imaging using a full Stokes imaging system with advanced polarization image analysis algorithms for improved diagnostics. The key component of the Stokes imaging system is the electrically tunable retarder, enabling high‐speed operation of the system to acquire four intensity images sequentially. From the acquired intensity images, four Stokes vector images can be computed to obtain complete polarization information. Polarization image analysis algorithms are then developed to analyze Stokes polarization images for cell or tissue classification. Specifically, wavelet transforms are first applied to the Stokes components for initial feature analysis and extraction. Artificial neural networks (ANNs) are then used to extract diagnostic features for improved classification and prediction. In this study, phantom experiments have been conducted using a prototyped Stokes polarization imaging device. In particular, several types of phantoms, consisting of polystyrene latex spheres in various diameters, were prepared to simulate different conditions of epidermal layer of skin. The experimental results from phantom studies and a plant cell study show that the classification performance using Stokes images is significantly improved over that using the intensity image only.
Compact and Broadband Microstrip Antennas for Next Generation High-Speed Wireless Communication Using HIPERLAN/2
Authors: Roy Jibendu Sekhar , Thomas Milind
Published: November 2007

The investigations on rectangular-slot-loaded and V-slot-loaded proximity-coupled microstrip antennas are reported. The performances of two antennas are investigated for the application in wireless local area network 2 (HIPERLAN/2) using IE3D software and the computed results are verified by measurement. Results show that the antennas have wide bandwidth and moderate gain and may be used as small, compact antennas for HIPERLAN/2 communication.
Onb-I-Open Sets andb-I-Continuous Functions
Authors: Akdağ Metin
Published: November 2007

We studied some more properties ofb-I-open sets and obtained several characterizations ofb-I-continuous functions which are introduced by Caksu Guler and Aslim (2005). We also investigated their relationship with other types of functions.
An Algorithm Based on Resolvant Operators for Solving Positively Semidefinite Variational Inequalities
Authors: Sun Juhe , Zhang Shaowu , Zhang Liwei
Published: November 2007

A new monotonicity, "Equation missing"-monotonicity, is introduced, and the resolvant operator of an "Equation missing"-monotone operator is proved to be single-valued and Lipschitz continuous. With the help of the resolvant operator, the positively semidefinite general variational inequality (VI) problem VI "Equation missing" is transformed into a fixed point problem of a nonexpansive mapping. And a proximal point algorithm is constructed to solve the fixed point problem, which is proved to have a global convergence under the condition that "Equation missing" in the VI problem is strongly monotone and Lipschitz continuous. Furthermore, a convergent path Newton method is given for calculating "Equation missing"-solutions to the sequence of fixed point problems, enabling the proximal point algorithm to be implementable.
On Further Analogs of Hilbert's Inequality
Authors: Li Yongjin , Qian You , He Bing
Published: November 2007

By introducing the function|lnx−lny|/(x+y+|x−y|), we establish new inequalities similar to Hilbert's type inequality for integrals. As applications, we give its equivalent form as well.
A Broadband Circularly Polarized Stacked Probe-Fed Patch Antenna for UHF RFID Applications
Authors: Chung Hang Leong , Qing Xianming , Chen Zhi Ning
Published: November 2007

A broadband circularly polarized stacked probe-fed antenna suitable for UHF RFID applications is presented and studied. The proposed antenna is fed by two probes which are connected to a hybrid coupler. Two parasitic patches are stacked above a primary probe-fed patch to enhance the bandwidth of the antenna. The optimized antenna prototype achieves gain of more than 6.5 dBic, axial ratio of less than 3.0 dB, and return loss of less than−15 dB over the UHF band of 820–980 MHz (17.7%). Parametric studies are carried out to demonstrate the effects of antenna geometry parameters on the performance. The proposed antenna can be a good candidate for UHF RFID applications.
OnP3-Paracompact Spaces
Authors: Al-Zoubi Khalid , Al-Ghour Samer
Published: November 2007

Mashhour et al. [1] introduced the notions ofP1-paracompactness andP2-paracompactness of topological spaces in terms of preopen sets. In this paper, we introduce and investigate a weaker form of paracompactness which is calledP3-paracompact. We obtain various characterizations, properties, examples, and counterexamples concerning it and its relationships with other types of spaces. In particular, we show that if a space(X,T)is quasi-submaximal, then(X,T)is paracompact if it isP3-paracompact.
Kinetics and Mechanism of Paracetamol Oxidation by Chromium(VI) in Absence and Presence of Manganese(II) and Sodiumdodecyl Sulphate
Authors: Ilyas Mohammed , Malik Maqsood Ahmad , Andrabi Syed Misbah Zahoor , Khan Zaheer
Published: November 2007

The kinetics of paracetamol oxidation are first order each in [paracetamol] and [HClO4]. The kinetic study shows that the oxidation proceeds in two steps. The effects of anionic micelles of sodiumdodecyl sulphate (SDS) and complexing agents (ethylenediammine tetraacetic acid (EDTA) and 2,2′-bipyridyl (bpy)) were also studied. Fast kinetic spectrophotometric method has been described for the determination of paracetamol. The method is based on the catalytic effect of manganese(II) on the oxidation of paracetamol by chromium(VI) in the presence of HClO4 (= 0.23 mol dm−3). Optimum reaction time is 4 to 6 minutes at a temperature of 30∘C. The addition of manganese(II) ions largely decreased the absorbance of chromium(VI) at 350 nm. This reaction can be utilized for the determination of paracetamol in drugs.
Well-AlignedIrO2Nanocrystals
Authors: Korotcov Alexandru , Chen Reui-San , Hsu Hung-Pin , Huang Ying-Sheng , Tsai Dah-Shyang , Tiong Kwong-Kau
Published: November 2007

We review the results of synthesis of well-alignedIrO2nanocrystals (NCs) on sapphire (SA), LiNbO3(LNO), LiTaO3(LTO) substrates via reactive magnetron sputtering and metal-organic chemical vapor deposition. The surface morphology and structural properties of the as-deposited NCs were characterized. Field emission scanning electron microscopy micrographs reveal that NCs grown on SA(100)/LNO(100) are vertically aligned, while the NCs on SA(012)/LTO(012) and SA(110) contain singly and doubly tilted alignments, respectively, with a tilt angle of∼35∘from the normal to the substrates. NCs grown on SA(001) show in-plane alignment with mosaic structure. The X-ray diffraction results indicate that the NCs are (001), (101), and (100) oriented on SA(100)/LNO(100), SA(012)/LTO(012)/SA(110), and SA(001) substrates, respectively. A strong substrate effect on the alignment of theIrO2NCs deposition has been demonstrated. The roles of different substrates in the formation of various textures of nanocrystallineIrO2are studied and the possible mechanisms have been discussed.
On the Semiparametric Efficiency of the Scott-Wild Estimator under Choice-Based and Two-Phase Sampling
Authors: Lee Alan
Published: November 2007

Using a projection approach, we obtain an asymptotic information bound for estimates of parameters in general regression models under choice-based and two-phase outcome-dependent sampling. The asymptotic variances of the semiparametric estimates of Scott and Wild (1997, 2001) are compared to these bounds and the estimates are found to be fully efficient.
IPEX as a Result of Mutations in FOXP3
Authors: van der Vliet Hans J. J. , Nieuwenhuis Edward E.
Published: November 2007

Immunodysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a rare disorder caused by mutations in theFOXP3gene that result in the defective development ofCD4+CD25+regulatory T cells which constitute an important T cell subset involved in immune homeostasis and protection against autoimmunity. Their deficiency is the hallmark of IPEX and leads to severe autoimmune phenomena including autoimmune enteropathy, dermatitis, thyroiditis, and type 1 diabetes, frequently resulting in death within the first 2 years of life. Apart from its clinical implications, IPEX illustrates the importance of immunoregulatory cells such asCD4+CD25+regulatory T cells.
Thalamus Segmentation from Diffusion Tensor Magnetic Resonance Imaging
Authors: Duan Ye , Li Xiaoling , Xi Yongjian
Published: November 2007

We propose a semi‐automatic thalamus and thalamus nuclei segmentation algorithm from Diffusion Tensor Magnetic Resonance Imaging (DT‐MRI) based on the mean‐shift algorithm. Comparing with existing thalamus segmentation algorithms which are mainly based on K‐means algorithm, our mean‐shift based algorithm is more
flexible and adaptive. It does not assume a Gaussian distribution or a fixed number of clusters. Furthermore, the single parameter in the mean‐shift based algorithm supports hierarchical clustering naturally.