bluuebunny/crossref_metadata_2025 huggingface dataset:
VARIABLE-COEFFICIENT MIURA TRANSFORMATIONS AND INTEGRABLE PROPERTIES FOR A GENERALIZED VARIABLE-COEFFICIENT KORTEWEG–de VRIES EQUATION FROM BOSE–EINSTEIN CONDENSATES WITH SYMBOLIC COMPUTATION
Authors: LI JUAN , TIAN BO , MENG XIANG-HUA , XU TAO , ZHANG CHUN-YI , ZHANG YA-XING
Published: March 2009

In this paper, a generalized variable-coefficient Korteweg–de Vries (KdV) equation with the dissipative and/or perturbed/external-force terms is investigated, which arises in arterial mechanics, blood vessels, Bose gases of impenetrable bosons and trapped Bose–Einstein condensates. With the computerized symbolic computation, two variable-coefficient Miura transformations are constructed from such a model to the modified KdV equation under the corresponding constraints on the coefficient functions. Meanwhile, through these two transformations, a couple of auto-Bäcklund transformations, nonlinear superposition formulas and Lax pairs are obtained with the relevant constraints. Furthermore, the one- and two-solitonic solutions of this equation are explicitly presented and the physical properties and possible applications in some fields of these solitonic structures are discussed and pointed out.
MAGNETIC PROPERTIES AND STRUCTURE OF NANO-SIZE NiZn FERRITE SYNTHESIZED BY THE REFLUXING CO-PRECIPITATION METHOD
Authors: ZHANG YI , JIAO QIGANG , ZHAI YA , BAI XIAOJUN , DU JUN , ZHAI HONGRU
Published: March 2009

A series of nanoparticle powders of Ni 1-x Zn x Fe 2 O 4 (x = 0, 0.3, 0.4, 0.5, 0.6 and 0.7) ferrites were synthesized by the refluxing method at relatively low temperatures. X-ray diffraction measurements were performed to yield the grain size of the particles as a function of the amount x of Zn substitution and the lattice parameter was found to increase with increasing x. Mössbauer spectroscopy was performed at room temperature. The spectra exhibit ferromagnetic hyperfine splitting sextet peaks with a doublet peak overlapped at its center as Zn contents x < 0.6. The fitted hyperfine magnetic field of the octahedral sublattice and tetrahedral sublattice all decrease with increasing Zn content. The area of the tetrahedral sublattice decreases with increasing x and that of the octahedral sites increases for low Zn concentration, as a result of substitution of iron by zinc in the tetrahedral sites. The area of the doublet increases constantly. Systematic magnetization measurements gave evidence that the doublet in the spectra originated from the superparamagnetism of the particles at room temperature as Zn content x < 0.6.
LATTICE BOLTZMANN SIMULATION FOR VARIOUS GEOMETRIES OF SOLID OXIDE FUEL CELLS
Authors: XU YOUSHENG , LIU YANG , LIN JI , WU FENGMIN
Published: March 2009

Based on the models of the porous-electrode, a lattice Boltzmann model of a solid oxide fuel cell is presented, which allows the computation of the local distributions of the electrical potential, current density, and concentration of the chemical species. The physics of the cell and the simplifying assumptions are presented; a sketch of the numerical procedure is also given. The numerical results obtained with hydrogen as the fuel are compared with results from other simulation codes which were developed for a planar geometry. The numerical results show that the counter-flow design as being the most efficient. Furthermore, and with increasing the percent H2 in the fuel stream, the voltage drops profile alters from precipitous to gentle. These results are excellent.
LARGE EDDY SIMULATION OF A 3D CHANNEL FLOW WITH WALL-MOUNTED RECTANGULAR CYLINDERS
Authors: CHEN ZHIHUA , JIANG XIAOHANG , HANG JUNLI
Published: March 2009

Large eddy simulation was applied to simulate the compressible flow past multiple wall-mounted rectangular cylinders in a channel flow. The dynamic sub-grid stress model was employed to approximate the sub-grid scale effects. For flow past single wall-mounted cylinder, our calculated results agree well with the results of both previous experimental and numerical results which showed the formation and diffusion of vortexes around the cylinder. Flow past two wall-mounted cylinders has also been simulated numerically and our numerical results disclosed the formation of the vortex street behind the second cylinder and the developing process of flow field, which is important for practical engineering application.
HIGH-ORDER DISCONTINUOUS GALERKIN SOLUTION OF LOW-RE VISCOUS FLOWS
Authors: LU HONGQIANG
Published: March 2009

In this paper, the BR2 high-order Discontinuous Galerkin (DG) method is used to discretize the 2D Navier-Stokes (N-S) equations. The nonlinear discrete system is solved using a Newton method. Both preconditioned GMRES methods and block Gauss-Seidel method can be used to solve the resulting sparse linear system at each nonlinear step in low-order cases. In order to save memory and accelerate the convergence in high-order cases, a linear p-multigrid is developed based on the Taylor basis instead of the GMRES method and the block Gauss-Seidel method. Numerical results indicate that highly accurate solutions can be obtained on very coarse grids when using high order schemes and the linear p-multigrid works well when the implicit backward Euler method is employed to improve the robustness.
ON THE PROLONG ATTACHMENT OF LEADING EDGE VORTEX ON A FLAPPING WING
Authors: LIM T. T. , TEO C. J. , LUA K. B. , YEO K. S.
Published: March 2009

In this paper, we take a fundamental approach to investigate the effect of spanwise flow on the prolonged attachment of leading edge vortex (LEV) on a flapping wing. By imposing a constant acceleration-constant velocity flow on elliptic wings of various sweep angles and angles of attack, our experimental and numerical results show that while spanwise flow per se has negligible influence on the prolong attachment of the LEV, vortex stretching can significantly delay detachment of the LEV, even for a small spanwise flow.
Endothelin rather than 20-HETE contributes to loss of pial arteriolar dilation during focal cerebral ischemia with and without polymeric hemoglobin transfusion
Authors: Cao Suyi , Wang Liang-Chao , Kwansa Herman , Roman Richard J. , Harder David R. , Koehler Raymond C.
Published: March 2009

Partial exchange transfusion with a cell-free hemoglobin (Hb) polymer during transient middle cerebral artery occlusion (MCAO) reduces infarct volume but fails to increase blood flow, as might be expected with the induced decrease in hematocrit. In ischemic brain, endothelin antagonists are known to produce vasodilation. In nonischemic brain, pial arterioles constrict after Hb exchange transfusion, and the constriction is blocked by an inhibitor of 20-HETE synthesis. We tested the hypothesis that a 20-HETE synthesis inhibitor and an endothelin A receptor antagonist increase pial arteriolar dilation after Hb exchange transfusion during MCAO. Pial arteriolar diameter was measured in the ischemic border region of the distal MCA border region through closed cranial windows in anesthetized rats subjected to the filament model of MCAO. During 2 h of MCAO, pial arteriolar dilation gradually subsided from 37 ± 3 to 7 ± 5% (±SE). Compared with residual dilation at 2 h of MCAO with vehicle superfusion (14 ± 3%), loss of dilation was not prevented by superfusion of a 20-HETE synthesis inhibitor (21 ± 5%), partial Hb exchange transfusion (7 ± 5%) that decreased hematocrit to 23%, or a combination of the two (5 ± 5%). However, loss of dilation was prevented by superfusion of an endothelin A receptor antagonist with (35 ± 4%) or without (32 ± 5%) Hb transfusion. Pial artery constriction during reperfusion was attenuated by HET0016 alone and by BQ610 with or without Hb transfusion. Systemic administration of the endothelin antagonist during prolonged MCAO increased blood flow in the border region. Thus loss of pial arteriolar dilation in the ischemic border region during prolonged MCAO depends on endothelin A receptor activation, and this effect was independent of the presence of cell-free Hb polymers in the plasma. In contrast to previous work in nonischemic brain, inhibition of oxygen-dependent 20-HETE synthesis does not significantly influence the pial arteriolar response to polymeric Hb exchange transfusion during focal ischemia.
Exercise affects tissue lymphocyte apoptosis via redox-sensitive and Fas-dependent signaling pathways
Authors: Krüger K. , Frost S. , Most E. , Völker K. , Pallauf J. , Mooren F. C.
Published: March 2009

Intensive and exhaustive exercise induces an activation of blood T-lymphocytes, which seems to be terminated by apoptotic processes in the postexercise period. Here, we report that exercise-induced T-lymphocyte apoptosis is a systemic phenomenon occurring in various lymphoid and nonlymphoid tissues. The apoptosis rate could be related to exercise intensity and type. Although in some tissues, such as the spleen and Peyer's patches, an early start of apoptosis (1–3 h postexercise) could be detected, a delayed apoptosis (24 h postexercise) was observed in lung, bone marrow, and lymph nodes. Further analysis showed a similar apoptosis distribution among lymphocyte subpopulations. We tested whether components of the extrinsic or the intrinsic apoptotic pathways or both were involved in these processes. Elevated levels of lipid peroxidation-product malondialdehyde (MDA), indicating an increased production of reactive oxygen species (ROS), were found after exercise in Peyer's patches, lung, and spleen, but not in lymph nodes. Application of N-acetyl-cysteine (NAC) prevented exercise-induced T-cell apoptosis completely in spleen and bone marrow, partially in lung and Peyer's patches, while it was ineffective in lymph nodes. Additionally, exercise addressed the Fas-mediated apoptosis. The percentage of Fas-receptor (Fas+) and Fas-ligand positive (FasL+) lymphocytes was enhanced in Peyer's patches after exercise. Moreover, FasL+ T cells were increased in the lung, while in lymph nodes Fas+ cells were increased. The critical role of Fas signaling in exercise-induced apoptosis was supported by using Fas-deficient MRL/lpr-mice. In Fas-deficient mice, exercise-induced T-lymphocyte apoptosis was prevented in spleen, lung, bone marrow, and lymph nodes, but not in Peyer's patches. These data demonstrate that exercise-induced lymphocyte apoptosis is a transient systemic process with tissue-type specific apoptosis-inducing mechanisms, whose relevance for the adaptive immune competence remains to be shown.
Marinobufagenin induces increases in procollagen expression in a process involving protein kinase C and Fli-1: implications for uremic cardiomyopathy
Authors: Elkareh Jihad , Periyasamy Sankaridrug M. , Shidyak Amjad , Vetteth Sandeep , Schroeder Jeremy , Raju Vanamala , Hariri Imad M. , El-Okdi Nasser , Gupta Shalini , Fedorova Larisa , Liu Jiang , Fedorova Olga V. , Kahaleh M. Bashar , Xie Zijian , Malhotra Deepak , Watson Dennis K. , Bagrov Alexei Y. , Shapiro Joseph I.
Published: March 2009

The cardiotonic steroid marinobufagenin (MBG) has been implicated in the pathogenesis of experimental uremic cardiomyopathy, which is characterized by progressive cardiac fibrosis. We examined whether the transcription factor Friend leukemia integration-1 (Fli-1) might be involved in this process. Fli-1-knockdown mice demonstrated greater cardiac collagen-1 expression and fibrosis compared with wild-type mice; both developed increased cardiac collagen expression and fibrosis after 5/6 nephrectomy. There was a strong inverse relationship between the expressions of Fli-1 and procollagen in primary culture of rat cardiac and human dermal fibroblasts as well as a cell line derived from renal fibroblasts and MBG-induced decreases in nuclear Fli-1 as well as increases in procollagen-1 expression in these cells. Transfection of a Fli-1 expression vector prevented increased procollagen-1 expression from MBG. MBG exposure induced a rapid translocation of the δ-isoform of protein kinase C (PKCδ) to the nucleus. This translocation was prevented by pharmacological inhibition of phospholipase C, and MBG-induced increases in procollagen-1 expression were prevented with a PKCδ- but not a PKCα-specific inhibitor. Finally, immunoprecipitation studies strongly suggest that MBG induced phosphorylation of Fli-1. We feel these data support a causal relationship with MBG-induced translocation of PKCδ, which results in phosphorylation of as well as decreases in nuclear Fli-1 expression, which, in turn, leads to increases in collagen production. Should these findings be confirmed, we speculate that this pathway may represent a therapeutic target for uremic cardiomyopathy as well as other conditions associated with excessive fibrosis.
Infant Brain Stem Is Prone to the Generation of Spreading Depression During Severe Hypoxia
Authors: Funke Frank , Kron Miriam , Dutschmann Mathias , Müller Michael
Published: March 2009

Spreading depression (SD) resembles a concerted, massive neuronal/glial depolarization propagating within the gray matter. Being associated with cerebropathology, such as cerebral ischemia or hemorrhage, epileptic seizures, and migraine, it is well studied in cortex and hippocampus. We have now analyzed the susceptibility of rat brain stem to hypoxia-induced spreading depression-like depolarization (HSD), which could critically interfere with cardiorespiratory control. In rat brain stem slices, severe hypoxia (oxygen withdrawal) triggered HSD within minutes. The sudden extracellular DC potential shift of approximately −20 mV showed the typical profile known from other brain regions and was accompanied by an intrinsic optical signal (IOS). Spatiotemporal IOS analysis revealed that in infant brain stem, HSD was preferably ignited within the spinal trigeminal nucleus and then mostly spread out medially, invading the hypoglossal nucleus, the nucleus of the solitary tract (NTS), and the ventral respiratory group (VRG). The neuronal hypoxic depolarizations underlying the generation of HSD were massive, but incomplete. The propagation velocity of HSD and the associated extracellular K+ rise were also less marked than in other brain regions. In adult brain stem, HSD was mostly confined to the NTS and its occurrence was facilitated by hypotonic solutions, but not by glial poisoning or block of GABAergic and glycinergic synapses. In conclusion, brain stem tissue reliably generates propagating HSD episodes, which may be of interest for basilar-type migraine and brain stem infarcts. The preferred occurrence of HSD in the infant brain stem and its propagation into the VRG may be of importance for neonatal brain stem pathology such as sudden infant death syndrome.
PKA Has a Critical Role in Synaptic Delivery of GluR1- and GluR4-Containing AMPARs During Initial Stages of Acquisition of In Vitro Classical Conditioning
Authors: Zheng Zhaoqing , Keifer Joyce
Published: March 2009

The cyclic AMP-dependent protein kinase (PKA) signaling pathway has been shown to be important in mechanisms of synaptic plasticity, although its direct and downstream signaling effects are not well understood. Using an in vitro model of eyeblink classical conditioning, we report that PKA has a critical role in initiating a signaling cascade that results in synaptic delivery of glutamate receptor 1 (GluR1)- and GluR4-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) in abducens motor neurons during conditioning. PKA and the Ca2+-calmodulin–dependent protein kinases (CaMKs) II and IV are activated early in conditioning and are required for acquisition and expression of conditioned responses (CRs). cAMP-response-element-binding protein (CREB) is also activated early in conditioning but is blocked by coapplication of inhibitors to PKA and the CaMKs, suggesting that CREB is downstream of those signaling cascades. Moreover, evidence suggests that PKA activates extracellular signal-regulated kinase, which is also required for conditioning. Imaging studies after conditioning further indicate that colocalization of GluR1 AMPAR subunits with the synaptic marker synaptophysin requires PKA, but is insensitive to the N-methyl-d-aspartate receptor (NMDAR) inhibitor d,l-AP5. PKA activation also leads to synaptic localization of GluR4 subunits that, unlike GluR1, is dependent on NMDARs and is mediated by CaMKII. Together with previous studies, our findings support a two-stage model of AMPAR synaptic delivery during acquisition of classical conditioning. The first stage involves synaptic incorporation of GluR1-containing AMPARs that serves to activate silent synapses. This allows a second stage of NMDAR- and protein kinase C–dependent delivery of GluR4 AMPAR subunits that supports the acquisition of CRs.
Oleic Acid Directly Regulates POMC Neuron Excitability in the Hypothalamus
Authors: Jo Young-Hwan , Su Ya , Gutierrez-Juarez Roger , Chua Streamson
Published: March 2009

The mammalian CNS relies on a constant supply of external glucose for its undisturbed operation. However, neurons can readily switch to using fatty acids and ketones as alternative fuels. Here, we show that oleic acid (OA) excites pro-opiomelanocortin (POMC) neurons by inhibition of ATP-activated potassium (KATP) channels. The involvement of KATP channels is further supported by experiments in SUR1 KO animals. Inhibition of β-oxidation using carnitine palmitoyltransferase-1 inhibitors blocks OA-induced depolarization. The depolarizing effect of OA is specific because it is not mimicked by octanoic acid. Furthermore, OA does not regulate the excitability of agouti-related peptide neurons. High-fat feeding alters POMC neuron excitability, but not its response to OA. Thus β-oxidation in POMC neurons may mediate the appetite-suppressing (anorexigenic) effects of OA.
Dynamic Bargaining and the Prospects for Learning in the Petroleum Industry: The Case of Kazakhstan
Authors: Hosman Laura
Published: March 2009

This article examines the bargaining interface between petroleum-rich developing countries and large multinational corporations, with an application to the case of Kazakhstan, formerly a Soviet Republic. In the analytic narrative tradition, this article combines a case study with an extensive form game, applying Theodore Moran's dynamic bargaining theory, which posits that, over time and through repeated interaction, developing countries do better for themselves, incrementally improving their outcomes through bargaining and strategic interaction, thereby advancing along a learning curve. The application of this theory is systematized through the utilization of game theory; an extensive game modeled on strategic, iterated bargaining behavior between the two actors is introduced. This dynamic game allows for the recalculation of strategies based on the players' revealed moves, allowing for the concept of learning while doing. The game is then applied to Kazakhstan's particular situation. The application of Moran's theory through the use of a generalizable game provides a method for resource-rich developing countries—particularly those in the nascent stages of developing these industries—to systematize the negotiation process and accelerate their ascent on a bargaining learning curve.
Measuring Children's Media Use in the Digital Age
Authors: Vandewater Elizabeth A. , Lee Sook-Jung
Published: March 2009

In this new and rapidly changing era of digital technology, there is increasing consensus among media scholars that there is an urgent need to develop measurement approaches which more adequately capture media use The overarching goal of this paper is facilitate the development of measurement approaches appropriate for capturing children's media use in the digital age. The paper outlines various approaches to measurement, focusing mainly on those which have figured prominently in major existing studies of children's media use. We identify issues related to each technique, including advantages and disadvantages. We also include a review of existing empirical comparisons of various methodologies. The paper is intended to foster discussion of the best ways to further research and knowledge regarding the impact of media on children.
Young Children and Media
Authors: Christakis Dimitri A. , Zimmerman Frederick J
Published: March 2009

Although television viewing has been a normative activity for 50 years, the rise of infant viewing is a relatively recent phenomenon. The American Academy of Pediatrics discourages TV viewing in the first two years of life. The scientific evidence base supporting this recommendation has been meager but is growing. This article reviews the limitations of our current knowledge and argues in favor of additional focused research on media's effects on very young children.
An Ecological Perspective on the Media and Youth Development
Authors: McHale Susan M. , Dotterer Aryn , Kim Ji-Yeon
Published: March 2009

From an ecological perspective, daily activities are both a cause and a consequence of youth development. Research on youth activities directs attention to the processes through which daily activities may have an impact on youth, including (a) providing chances to learn and practice skills, (b) serving as a forum for identity development, (c) affording opportunities to build social ties, (d) connecting youth to social institutions, and (e) keeping youth from engaging in other kinds of activities. Youth's daily activities, in turn, both influence and are influenced by the multilayered ecology within which their lives are embedded, an ecology that ranges from the proximal contexts of everyday life (e.g., family, peer group) to the larger political, economic, legal, and cultural contexts of the larger society. The article concludes with consideration of methodological issues and directions for research on the media and youth development.
Mass Shootings in Schools
Authors: Kleck Gary
Published: March 2009

The most frequent policy lesson drawn following the Columbine school shootings was the need for more gun controls. Review of the details of both Columbine and other contemporary school shootings indicates, however, that the specific gun control measures proposed in their aftermath were largely irrelevant and almost certainly could not have prevented the incidents or reduced their death tolls. These measures included restrictions on gun shows, child access prevention laws mandating locking up guns, and bans on assault weapons. Ironically, exploitation of school shootings for the advocacy of irrelevant gun controls may have obscured the genuine merits of various gun control measures for reducing “ordinary” gun violence. Thus, mass school shootings provided the worst possible basis for supporting gun control.
Breastfeeding Does Not Protect Against Urinary Tract Infection in the First 3 Months of Life, but Vitamin D Supplementation Increases the Risk by 76%
Authors: Katikaneni Ranjitha , Ponnapakkam Tulasi , Ponnapakkam Adharsh , Gensure Robert
Published: March 2009

Our goal was to determine if breastfeeding provides any protection against urinary tract infection (UTI) and if vitamin D supplementation imposes any additional risks for UTI in infants < 3 months of age. In this study, 40% of the children who had urine cultures were breastfed, and 18.7% of the children were exclusively breastfed. Twenty percent of all of the urine cultures tested positive, and this number was greater in females (22.5%) than in males (18.1%, P < .05). There was no significant difference between the rates of positive urine cultures in exclusively breastfed (22% vs 21%, nonsignificant [NS]) formula-fed infants. The relative risk of UTI with breastfeeding versus formula feeding was 1.03 (0.58-1.82), and any breastfeeding versus no breastfeeding was 0.92 (0.58-1.45). Vitamin D supplementation increased the UTI risk, with a relative risk of 1.76 (1.07-2.91, P < .05). However, only formula-fed infants showed an increased risk of UTI after vitamin D supplementation.
Late Effects in Long-Term Survivors After Treatment for Childhood Acute Leukemia
Authors: Haddy Theresa B. , Mosher Revonda B. , Reaman Gregory H.
Published: March 2009

Background. This is a report of late effects in childhood cancer survivors seen in the follow-up clinic of a single institution. Materials and methods. There were 324 acute leukemia survivors in the database of the Long Term Follow Up Clinic of Children's National Medical Center from January 1, 1997, through June 30, 2005. Results. Of the 324 acute leukemia survivors, 228 were white, 48 black, 20 Hispanic, and 12 other. Their follow-up time was 0 to 25 years (mean 5.3 years). One or more adverse events occurred in 74.1% of the 324 survivors. Defective physical growth was most commonly reported, followed by disturbed neurocognitive function, emotional difficulties, cardiac abnormalities, hypertension, osteoporosis/osteopenia, fractures, and second neoplasms. More black and Hispanic children had acute myeloid leukemia, relapses, cardiac problems, and hypertension than white and other subjects. Conclusion. Childhood cancer survivors require lifelong monitoring, with prompt identification and treatment of adverse late effects.
Characteristics and Preparation of Polymer/Graphite Composite Bipolar Plate for PEM Fuel Cells
Authors: Chen Hui  , Liu Hong-Bo , Li Jian-Xin , Yang Li  , He Yue-De
Published: March 2009

A novel concept of composite bipolar plate composed of modified phenolic resin, graphite, and carbon black with thickness less than 2mm has been successfully prepared by the bulk molding process at ambient temperature. This study investigates a potential approach to improve the properties of composite bipolar plate by choosing appropriate graphite particle size distributions and carbon black added means. The effects of resin content, molding pressure, curing temperature, graphite particle size distribution, graphite sorts, and carbon black on the properties of composite bipolar plate have been studied. The optimum processing conditions for preparing composite bipolar plate are: resin content 15—20wt%; molding pressure 10—12MPa; curing temperature 180°C; graphite particle size distribution -200/+325 mesh; carbon black content 4—5 wt%; and carbon black initially dispersed in resin with supersonic purifier. Under optimum conditions, we have produced composite bipolar plate with electrical conductivity higher than 80 S/cm and flexural strength higher than 40 MPa. In addition, this composite bipolar plate was thermally stable from room temperature to 420°C.
Estimating Preference-Based Health Utilities Index Mark 3 Utility Scores for Childhood Conditions in England and Scotland
Authors: Petrou Stavros , Kupek Emil
Published: March 2009

Background . A common feature of studies that have compiled lists or catalogues of preference-based health-related quality-of-life weights for inclusion within quality-adjusted life years (QALYs) is their focus upon adult populations. More generally, utility measurement in or on behalf of children has been constrained by a number of methodological concerns. Objective . To augment previous catalogues of preference-based health-related quality-of-life weights by estimating preference-based Health Utilities Index Mark 3 (HUI3) multiattribute utility scores associated with a wide range of childhood conditions. Methods . Data for 2236 children from the ``Disability Survey 2000: Survey of Young People With a Disability and Sport'' formed the basis of this investigation. Ordinary least squares (OLS), Tobit, and censored least absolute deviations (CLAD) regression methods were used to estimate adjusted marginal disutilities for each condition from 2 thresholds: 1) a threshold of 1.0 representing perfect health and 2) a normative childhood utility threshold. Results . Prespecified statistical tests indicated a preference for the OLS regression model over the Tobit and CLAD models. The unadjusted mean, median, 25th percentile and 75th percentile HUI3 multiattribute utility scores and adjusted marginal disutilities are presented for 43 conditions. Notably, based on the OLS estimator, the adjusted marginal disutilities for hydrocephalus; learning and physical disabilities; other syndromes and associations; meningitis, encephalitis, and other infections of the central nervous system; and microcephaly were estimated at —0.889 (95% confidence interval [CI]: —0.727, —1.000), —0.858 (95% CI: —0.727, —0.989), —0.838 (95% CI: —0.668, —1.000), —0.826 (95% CI: —0.677, —0.975), and —0.820 (95% CI: —0.670, —0.970), respectively, when a perfect health threshold was applied, and —0.814 (95% CI: —0.656, —0.979), —0.783 (95% CI: —0.656, —0.918), —0.763 (95% CI: —0.597, —0.937), —0.751 (95% CI: —0.606, —0.904), and —0.745 (95% CI: —0.598, —0.899), respectively, when a normative childhood utility threshold was applied. Conclusion . Our estimates and their associated distributions can be used for the purposes of QALY estimation by analysts conducting economic evaluations within the childhood context.
Valuing Health: Does Enriching a Scenario Lead to Higher Utilities?
Authors: Peeters Yvette , Stiggelbout Anne M.
Published: March 2009

Objectives . Patients have been found to value their own experienced health state higher than an investigator-constructed scenario of that health state. The aim of this study was to investigate if patients value their own experienced health state higher than a standard EQ-5D scenario of their health state and if ``enriching'' this scenario by adding individualized attributes reduces the differences between experienced health and the scenario. Methods . Face-to-face interviews were held with 129 patients with rheumatoid arthritis. Patients were asked to value in a time tradeoff their own experienced health; 6 standard EQ-5D scenarios, of which the 5th (untold to them) represented their own health state; and a standard EQ-5D scenario of their health state (identified as such) enriched with individual attributes. Results. The own experienced health state was not valued differently from the own standard EQ-5D state and was lower compared to the own enriched EQ-5D state of that same health state. An interaction effect was found for health status. Patients with better health did not report different values for their own experienced health compared with their own standard EQ-5D description; their own experienced state was rated lower than their own enriched EQ-5D description. Patients with poor health valued all 3 health states similarly. Surprisingly, utilities for scenarios enriched with exclusively negative individual attributes were not lower than those for the own standard EQ-5D description. Conclusion. The hypothesis that disparities in valuation can be attributed to EQ-5D description being too sparse was not confirmed.
Quantitative Assessment of Rotatory Instability after Anterior Cruciate Ligament Reconstruction
Authors: Tashiro Yasutaka , Okazaki Ken , Miura Hiromasa , Matsuda Shuichi , Yasunaga Takefumi , Hashizume Makoto , Nakanishi Yoshitaka , Iwamoto Yukihide
Published: March 2009

Background

Anterior cruciate ligament reconstruction successfully reduces anterior knee instability, but its effect on rotatory stability is not fully understood. In addition, a definitive method for the quantitative evaluation of rotatory instability remains to be established.

Hypothesis

Measurement of anterolateral tibial translation by open magnetic resonance imaging could positively correlate with the clinical grading of the pivot-shift test and would clarify residual rotatory abnormalities not shown by conventional methods for measurement of anterior stability.

Study Design

Controlled laboratory study.

Methods

An anterior cruciate ligament—reconstructed group (n = 21) and an anterior cruciate ligament—deficient group (n = 20) were examined using a Slocum anterolateral rotatory instability test in open magnetic resonance imaging. Anterior tibial translation was measured at the medial and lateral compartments by evaluating sagittal images. Clinical knee stability was evaluated before the above measurement using the pivot-shift test, KT-2000 arthrometer, and stress radiography. A cutoff value for anterolateral tibial translation relating to pivot-shift was determined using a receiver operating characteristic curve.

Results

Side-to-side differences of anterolateral tibial translation correlated with clinical grade of the pivot-shift test and stress radiography but not with KT-2000 arthrometry in both groups. The cutoff value was established as 3.0 mm. Although the mean anterolateral translation showed no difference, 9 reconstructed knees revealed greater than 3 mm of anterolateral tibial translation, whereas only 3 uninjured knees did.

Conclusion

Measurement using an open magnetic resonance imaging successfully quantified the remaining rotatory instability in anterior cruciate ligament—reconstructed knees.

Clinical Relevance

This method is a useful means for quantifying anterior cruciate ligament function to stabilize tibial rotation.
Structure, Mechanical, and Swelling Behaviors of Poly(vinyl alcohol)/SiO2 Hybrid Membranes
Authors: Juan Li  , Jinping Suo  , Runzhi Deng
Published: March 2009

Poly(vinyl alcohol) (PVA) has a wide application in industry and the biomedicine area, but its poor water resistance and insufficient mechanical strength have severely limited its application. To overcome these limitations, in this study, inorganic silica sol was used to modify organic PVA. The tensile results show that the tensile strength and Young’s modulus of these hybrid films were greatly improved compared to the neat PVA film. For the sample containing 20 wt% silica, compared to PVA matrix, considerable increases in tensile strength and Young’s modulus by factors of 1.9 and 3.2, respectively, were achieved. The solubility measurements showed that the hybrid has an enhanced water resistance, in other words, the solubility and degree of swelling decreased with the addition of silica. FTIR, DSC, XRD, and ESEM were used to investigate the chemical and crystal structure of the hybrids, morphology, and composition of the particles in the matrix, respectively. Strong interfacial bonding between the silica and the PVA matrix and homogenous distribution of the silica particles in PVA are supportive of markedly improved mechanical strength. These modified properties of PVA with the addition of silica broaden the applications of PVA, especially giving insight in to the applications of PVA in medical materials.
Compressive Strength Assessment of Geopolymer Composites by a Phenomenological Model
Authors: Radhakrishna  , Shashishankar A. , Udayashankar B.C. , Renuka Devi M.V.
Published: March 2009

Fly ash based geopolymer composite cubes were cast using class F fly ash, ground granulated blast furnace slag (GGBFS) as binders. The fluid-to-binder ratio was varied keeping all other parameters constant. The geopolymer composites were cured in different conditions. The composites were tested for compression at different ages. It is interesting to note that the variation of the strength with various fluid-to-binder ratios is unique irrespective of combination of materials, curing conditions, fluid content, and molarity of the fluid. The strength data generated was generalized to arrive at a phenomenological model. The model represents an unique pattern of strength development for the series of composite materials. The validity of the model was examined with an independent set of experimental data generated by the authors and Rangan. It was found that the predicted strengths were in line with the experimental strengths having a percentage error less than 6.0. The model is effective in re-proportioning of geopolymer composites in the field.
Decentralization of HR Functions
Authors: Tessema Mussie T. , Soeters Joseph L. , Ngoma Alex
Published: March 2009

In the past two decades, nearly every country in the world has felt the urge to decentralize some of its human resource (HR) functions. This article uses Singapore as a case study to illustrate how this urge has been addressed in civil service reforms during the past two decades. In so doing, the article also highlights the necessity as well as the theoretical and practical implications of the decentralization process to the organizational arrangement of HR functions in the civil service of Singapore. The article concludes that, as countries seek to decentralize HR functions in the civil service, understanding how this process works is cardinal to enhancing coordination and the efficient delivery of public services. For without this understanding, it is not possible to determine which functions must be decentralized and which ones must not be. Some popular myths and misconceptions about decentralization are also explored.
Fatal Self-poisoning in the UK and the Paracetamol/Dextropropoxyphene Combination
Authors: Dwyer P.S. , Jones I.F.
Published: March 2009

1 Coroners' files have been examined to ascertain the numbers of deaths involving self-poisoning with analgesic drugs with specific reference to the paracetamol/dextropropoxyphene combination. The period of study was 1976-1980. This report concentrates on cases in England, although reference is made to similar deaths occurring in Scotland and Northern Ireland.

2 Data have been collected extensively on a wide range of issues concerning fatal self-poisonings mainly by visiting coroners' offices in England to make direct investigation of records.

3 The total number of cases where the paracetamol/dextropropoxyphene combination can be considered as ingested in the self-poisoning episode is underestimated. The number of cases involving alcohol and/or other drugs taken together with the combination product is particularly underestimated.

4 Involvement of people aged 30 years and below comprises 32% of all cases.

5 'Gesture' overdoses comprise an estimated 14% of all cases in England.

6 An analysis of fatalities from cases where quantities in post-mortem blood of dextropropoxyphene < 1 μg/ml and paracetamol < 50 μg/ml are found and of cases where death occurs within 2 h of ingestion of the overdose has been carried out. The results are inconclusive. In most cases alcohol and/or other drugs are found to be involved. Critical inspection of coroners' files shows relatively few of these cases where the combination product is ingested on its own.

7 There is wide variability in the data available in coroners' files. In many cases data of value to this research are not recorded. Medical history and quantitative levels of drugs suspected (particularly dextropropoxyphene) are particular examples of factors which may not be recorded.

8 Office of Population, Censuses and Surveys (OPCS) mortality data are based on certified causes of death. Because of the underestimate of the involvement of this combination product and the under-reporting of other drug and/or alcohol ingestion with the combination, care must be exercised in quoting or drawing conclusions from OPCS statistics.
Mycophenolate mofetil and neurological diseases
Authors: Vermersch P , Stojkovic T , Seze J De
Published: March 2009

We describe experience with the use of mycophenolate mofetil (MMF) in neurological diseases. Although only small series of patients or case reports were described, MMF is promising in immune-mediated neuromuscular disorders. MMF has been used for the treatment of polymyositis, chronic inflammatory demyelinating polyradiculoneuropathy, and multifocal motor neuropathy. These studies showed that MMF is well tolerated and may be useful in some patients. MMF can be effective alone but mainly as an adjuvant therapy by reducing steroid requirements or the frequency of infusions of IVIg. MMF has also been tested alone as a single drug treatment or in combination with immunomodulatory drugs in multiple sclerosis in open surveillance trials or in phase II studies. None of these studies have been designed to demonstrate a clinical efficacy but preliminary results are very promising.
Mycophenolate mofetil and myasthenia gravis
Authors: Ciafaloni E
Published: March 2009

Myasthenia gravis (MG) represents the prototypic autoimmune disorder with well characterized immunopathology. Advances in the diagnosis and treatment of this neuromuscular transmission disorder have significantly improved the management of myasthenic patients. Unfortunately the currently available immunomodulating treatments have significant side effects and some patients do not tolerate them or adequately respond to them. Therefore the possibility of a new immunosuppressant agent that is safe, effective and has steroid-sparing effect is very appealing. Mycophenolate mofetil (MMF) has shown promising effects in MG patients in preliminary studies and is currently being studied in two prospective, randomized, double-blind, placebo controlled, multicenter trials to better establish its role in the treatment of MG.
Relationship of IL-2, IL-2R (CD25+), Soluble IL-2R and IL-4 with Disease Activity in SLE Patients
Authors: Cuadrado Maria J. , Marubayashi Miriam , Ortega Consuelo , Fernandez-Arcas Nieves , Garcia-Cozar Francisco , Pena Jose , Sanchez-Guijo Pedro , Santamaria Manuel
Published: March 2009

The plasma levels of interleukin-4 (IL-4), interleukin-2 (IL-2), soluble receptor of IL-2 (IL-2R) and T cell expression of IL-2 receptor chain (CD25+) were determined in an attempt to relate these parameters with disease activity in systemic lupus erythematosus (SLE). IL-4, IL-2 and sIL-2R plasma levels of SLE patients were significantly higher than those of the control group (P<0.05) while CD25+ expression was similar in both groups. Only sIL-2R levels were significantly higher (P<0.05) in active than in inactive patients.
Structure and Function of β2-Glycoprotein I: With Special Reference to the Interaction with Phospholipid
Authors: Hagihara Yoshihisa , Goto Yuji , Kato Hisao , Yoshimura Tetsuro
Published: March 2009

β2-Glycoprotein I (β2-GPI) is a cofactor in the recognition of a phospholipid antigen, cardiolipin, by anticardiolipin antibodies in autoimmune diseases such as systemic lupus erythematosus. We examined the interaction of various forms of bovine β2-GPI, such as its intact form, desialylated form (Asialo β2-GPI), N-terminal domain (domain 1) and the modified forms of β2-GPI and Asialo β2-GPI with nicks in their C-terminal domains (domain 5), with phospholipid liposomes under different conditions of pH and ionic strength. We found that at neutral pH and low ionic strength β2-GPI bound to liposome membranes containing cardiolipin with a dissociation constant (Kd) of 10−8 M. Phosphatidylglycerol, phosphatidylserine, phosphatidic acid or phosphatidylinositol bound to β2-GPI, but phosphatidylcholine did not. We also found that domain 1 and Asialo β2-GPI bound to cardiolipin with Kd values of 10−6 and 10−8 M, respectively, At neutral pH and both low and high ionic strengths, the affinities of nicked forms of β2-GPI and Asialo β2-GPI for cardiolipin were lower than those of intact forms but similar to that of domain 1.
Biology of endothelium
Authors: Maruyama I
Published: March 2009

Endothelial cells form a multifunctional cell lining that covers all of the inner surface of blood vessels and regulates several important physiological and pathological reactions. These include inflammation/immune reaction, blood vessel tonus, hemostasis/thrombosis, angiogenesis and so on. Thus, abnormalities of endothelial function may play crucial roles in the development of angitis syndrome, thrombosis/embolism, bleeding disseminated intravascular coagulation (DIC), and neovascularization in some pathological states including tumor growth and diabetic retinopathy. Research on endothelial cells now forms a new frontier termed ‘Endotheliology’.

Recent advances of the functional and structural aspects of endothelial cells are reviewed here mainly from the viewpoint of endothelial regulation of coagulation and the fibrinolytic system. First we show that the natural endothelial membrane protein thrombomodulin is localized not only on apical endothelial surface but also in caveolae. Since it has been reported that such factors involved in coagulation/fibrinolysis as tissue factor, tissue factor pathway inhibitor (TFPI), thrombin receptor and urokinase receptor are also localized in the caveolae, this membrane structure may act as a special component to regulate coagulation/fibrinolysis on the endothelial membrane surface.

Next we demonstrate the signaling pathway of the thrombin receptor. Thrombin cleaves the N-terminus of the receptor as a substrate, exposing a new N-terminus. This newly exposed N-terminus acts as a ligand and activates platelets, endothelial cells and vascular smooth-muscle cells. We have identified that the signal from the thrombin receptor activates NF-κB through the activation of protein C kinase, tyrosine kinase and MAP kinase, and results in proliferation of the cells. We have also shown that the receptor is over-expressed on platelets from diabetes patients.
β2-Glycoprotein I as a ‘Cofactor’ for anti-phospholipid reactivity with endothelial cells
Authors: Meroni PL , Papa N Del , Raschi E , Panzeri P , Borghi MO , Tincani A , Balestrieri G , Khamashta MA , Hughes GRV , Koike T , Krilis SA
Published: March 2009

β2-glycoprotein I (β2GPI) is a cofactor for anti-phospholipid (aPL) binding to cardiolipin (CL)-coated plates. β2GPI is also able to bind to endothelial cell (EC) membranes as supported by in-vivo as well as by in-vitro studies. The PL-binding site in the fifth domain of the molecule is involved in the adhesion to endothelium. Actually, specific mutations in this molecular portion abolish endothelium binding and a synthetic peptide spanning the sequence Glu274 –Cys288 of the CL-binding site displays comparable adhesion to EC monolayers. Heparan sulphate appears to be one of the anionic EC membrane structures with which cationic β2GPI interacts, as supported by studies with heparitinase-treated EC. β2GPI binding to EC might be related to its activity as endothelial growth factor or as a lipid-carrying glycoprotein. Adhesion of β2GPI to endothelial membranes offers suitable epitopes for circulating aPL that, once bound, can induce cell activation
Origin of antiphospholipid antibodies: Induction of aPL by viral peptides
Authors: Gharavi AE , Pierangeli SS
Published: March 2009

The clinical associations of antiphospholipid antibodies (aPL) are well recognized but the mechanism(s) causing the production of these antibodies are not yet known. We demonstrated the induction of pathogenic aPL antibodies that caused intrauterine fetal death and transverse myelopathy due to spinal cord infarction in mice by immunization with foreign β2GPl. We also induced aPL and anti-β2-GPI in mice by immunization with PL-binding viral peptides and hypothesized that in APS patients, aPL may be induced by β2GPl-like-PL-binding products of common human bacteria and viruses.
Detection of cerebral microemboli in APS — Introducing a novel investigation method and implications of analogies with carotid artery disease
Authors: Specker Ch , Perniok A , Brauckmann U , Siebler M , Schneider M
Published: March 2009

Patients with antiphospholipid syndrome (APS) are prone to thromboembolism. So far, the only predictive parameters for further complications are their number in patient's history and perhaps the titre of aPL. Derived from clinical investigation of stroke and obvious analogies between cerebrovascular ischemia (CVI) in patients with carotid artery disease (CAD) and patients with APS, a novel non-invasive method is introduced using transcranial Doppler (TCD) long-term monitoring to detect high energy ultrasonic signals (so called ‘microemboli’) in the cerebral vasculature. In patients with CAD, these microemboli proved to correlate with past and impending symptoms of CVI permitting therapeutic stratification by their detectability. In SLE and APS, this technique enabled identification of very similar signals in cerebral bloodstream of APS patients. Microemboli were highly associated with the history of CVI and the titre of aPL. Detection of microemboli offers new possibilities in risk estimation, therapeutic stratification and in studying pathophysiology of APS.