bluuebunny/crossref_metadata_2025 huggingface dataset:
Geology and Evolution of the Southern Dead Sea Fault with Emphasis on Subsurface Structure
Authors: Ben-Avraham Zvi , Garfunkel Zvi , Lazar Michael
Published: January 2008

The Dead Sea Fault is an active transform fault linking opening in the Red Sea with collision in the Taurus/Zagros Mountains. Motion is left-lateral and estimated at approximately 5–7 mm year−1. The fault is seismically active, and can be divided into two distinct structural segments. This study focuses on the southern segment based mainly on the wealth of geophysical data. Owing to transtention caused by oblique-slip and the overlapping of en-echelon fault strands, a series of pull-apart basins were formed along the fault's length. These basins are long and deep-reaching in places more than 10 km deep. They are characterized by extensional, compressional, and asymmetrical structures varying in size from large-scale (defining the general structure of the Dead Sea fault valley) to small-scale (defining the internal structure). This study examines the internal structure of these basins from south to north and summarizes the state of knowledge to date.
Evidence for KCNQ1 K+channel expression in rat zymogen granule membranes and involvement in cholecystokinin-induced pancreatic acinar secretion
Authors: Lee Wing-Kee , Torchalski Blazej , Roussa Eleni , Thévenod Frank
Published: January 2008

Secretion of enzymes and fluid induced by Ca2+in pancreatic acini is not completely understood and may involve activation of ion conductive pathways in zymogen granule (ZG) membranes. We hypothesized that a chromanol 293B-sensitive K+conductance carried by a KCNQ1 protein is expressed in ZG membranes (ZGM). In suspensions of rat pancreatic ZG, ion flux was determined by ionophore-induced osmotic lysis of ZG suspended in isotonic salts. The KCNQ1 blocker 293B selectively blocked K+permeability (IC50of ∼10 μM). After incorporation of ZGM into planar bilayer membranes, cation channels were detected in 645/150 mM potassium gluconate cis/trans solutions. Channels had linear current-voltage relationships, a reversal potential ( Erev) of −20.9 ± 0.9 mV, and a single-channel K+conductance ( gK) of 265.8 ± 44.0 pS ( n = 39). Replacement of cis 500 mM K+by 500 mM Na+shifted Erevto −2.4 ± 3.6 mV ( n = 3), indicating K+selectivity. Single-channel analysis identified several K+channel groups with distinct channel behaviors. K+channels with a gKof 651.8 ± 88.0 pS, Erevof −22.9 ± 2.2 mV, and open probability ( Popen) of 0.43 ± 0.06 at 0 mV ( n = 6) and channels with a gKof 155.0 ± 11.4 pS, Erevof −18.3 ± 1.8 mV, and Popenof 0.80 ± 0.03 at 0 mV ( n = 3) were inhibited by 100 μM 293B or by the more selective inhibitor HMR-1556 but not by the maxi-Ca2+-activated K+channel (BK channel) inhibitor charybdotoxin (5 nM). KCNQ1 protein was demonstrated by immunoperoxidase labeling of pancreatic tissue, immunogold labeling of ZG, and immunoblotting of ZGM. 293B also inhibited cholecystokinin-induced amylase secretion of permeabilized acini (IC50of ∼10 μM). Thus KCNQ1 may account for ZG K+conductance and contribute to pancreatic hormone-stimulated enzyme and fluid secretion.
Tempol improves renal hemodynamics and pressure natriuresis in hyperthyroid rats
Authors: Moreno Juan Manuel , Rodríguez Gómez Isabel , Wangensteen Rosemary , Alvarez-Guerra Miriam , Luna Juan de Dios , García-Estañ Joaquín , Vargas Félix
Published: January 2008

Hyperthyroidism in rats is associated with increased oxidative stress. These animals also show abnormal renal hemodynamics and an attenuated pressure-diuresis-natriuresis (PDN) response. We analyzed the role of oxidative stress as a mediator of these alterations by examining acute effects of tempol, a superoxide dismutase mimetic. The effects of increasing bolus doses of tempol (25–150 μmol/kg) on mean arterial pressure (MAP), renal vascular resistance (RVR), and cortical (CBF) and medullary (MBF) blood flow were studied in control and thyroxine (T4)-treated rats. In another experiment, tempol was infused at 150 μmol·kg−1·h−1 to analyze its effects on the glomerular filtration rate (GFR) and on PDN response in these animals. Tempol dose dependently decreased MAP and RVR and increased CBF and MBF in control and T4-treated rats, but the T4 group showed a greater responsiveness to tempol in all of these variables. The highest dose of tempol decreased RVR by 13.5 ± 2.1 and 5.5 ± 1.2 mmHg·ml−1·min−1 in hyperthyroid ( P < 0.01) and control rats, respectively. GFR was not changed by tempol in controls but was significantly increased in the hyperthyroid group. Tempol did not change the absolute or fractional PDN responses of controls but significantly improved those of hyperthyroid rats, although without attaining normal values. Tempol increased the slopes of the relationship between renal perfusion pressure and natriuresis (T4+tempol: 0.17 ± 0.05; T4: 0.09 ± 0.03 μeq·min−1·g−1·mmHg−1; P < 0.05) and reduced 8-isoprostane excretion in hyperthyroid rats. These results show that antioxidant treatment with tempol improves renal hemodynamic variables and PDN response in hyperthyroid rats, indicating the participation of an increased oxidative stress in these mechanisms.
Rosuvastatin is additive to high-dose candesartan in slowing progression of experimental mesangioproliferative glomerulosclerosis
Authors: Krämer Stephanie , Kron Susanne , Wang-Rosenke Yingrui , Loof Tanja , Khadzhynov Dmytro , Morgera Stanislao , Kawachi Hiroshi , Shimizu Fujio , Martini Sebastian , Neumayer Hans-H. , Peters Harm
Published: January 2008

Rosuvastatin is additive to high-dose candesartan in slowing progression of experimental mesangioproliferative glomerulosclerosis (GS). Progressive mesangioproliferative glomerulonephritis, mostly IgA nephropathy, is a major cause of end-stage kidney disease worldwide. In a chronic-progressive model of mesangioproliferative GS, we tested the renoprotective efficacy of rosuvastatin alone and in combination with a high-dose of the AT1blocker candesartan. Treatment was started 1 wk after disease induction (anti-thy1 antibody injection into uninephrectomized rats) and continued until week 20. Tubulointerstitial expression of the key fibrosis mediator transforming growth factor (TGF)-β served as the main marker of disease progression. Compared with the untreated GS rats (475 ± 52 pg/ml), tubulointerstitial TGF-β1protein expression was significantly reduced by both single therapies (rosuvastatin −47%, candesartan −51%, P < 0.01). Tubulointerstitial matrix accumulation (matrix score in GS: 64 ± 7%) was relatively reduced by −45 and −52%, respectively ( P < 0.01). The combination of rosuvastatin and candesartan had significantly greater effects on tubulointerstitial TGF-β1expression (−82% vs. GS) and matrix accumulation (−83% vs. GS) ( P < 0.001 vs. GS, P < 0.05 vs. single therapy) than either drug alone. Similar additive beneficial effects were observed for renal fibronectin and tissue inhibitor of metalloproteinase-1 expression, cell proliferation, macrophage infiltration, proteinuria, and kidney function. In conclusion, rosuvastatin limits the progressive course of anti-thy1-induced GS toward chronic tubulointerstitial fibrosis and renal insufficiency to a degree comparable to the one achieved by a high dose of the AT1antagonist candesartan. Combined treatment yields significantly greater actions on renal TGF-β overexpression and matrix accumulation, cell proliferation, and macrophage infiltration. The results suggest that rosuvastatin and an AT1blocker independently interfere with separate key pathways involved in the progression of chronic mesangioproliferative GS.
Activation of a local renin angiotensin system in podocytes by glucose
Authors: Durvasula Raghu V. , Shankland Stuart J.
Published: January 2008

ANG II is a critical mediator of diabetic nephropathy. Pharmacologic inhibition of ANG II slows disease progression beyond what could be predicted by the blood pressure lowering effects alone, suggesting the importance of nonhemodynamic pathways of ANG II in mediating disease. Podocyte injury and loss are cardinal features of diabetic nephropathy. Mounting evidence suggests that the podocyte is a direct target of ANG II-mediated signaling in diabetic renal disease. We have tested the hypothesis that high glucose leads to the activation of a local angiotensin system in podocytes and delineated the underlying pathways involved. Cultured podocytes were exposed to standard glucose (5 mM), high glucose (40 mM), or mannitol as an osmotic control. ANG II levels in cell lysates were measured in the presence or absence of inhibitors of angiotensin-converting enzyme (captopril), chymase (chymostatin), and renin (aliskiren) activity. The effects of glucose on renin and angiotensin subtype 1 receptor expression and protein levels were determined. Exposure to high glucose resulted in a 2.1-fold increase ANG II levels mediated through increased renin activity, as exposure to high glucose increased renin levels and preincubation with Aliskiren abrogated glucose-induced ANG II production. Relevance to the in vivo setting was demonstrated by showing glomerular upregulation of the prorenin receptor in a podocyte distribution early in the course of experimental diabetic nephropathy. Furthermore, high glucose increased angiotensin subtype 1 receptor levels by immunofluorescence and Western blot. Taken together, the resultant activation of a local renin angiotensin system by high glucose may promote progressive podocyte injury and loss in diabetic nephropathy.
Overlapping in vitro and in vivo specificities of the organic anion transporters OAT1 and OAT3 for loop and thiazide diuretics
Authors: Vallon Volker , Rieg Timo , Ahn Sun Young , Wu Wei , Eraly Satish A. , Nigam Sanjay K.
Published: January 2008

Organic anion transporter (OAT) genes have been implicated in renal secretion of organic anions, but the individual in vivo contributions of OAT1 (first identified as NKT) and OAT3 remain unclear. Potential substrates include loop diuretics (e.g., furosemide) and thiazide diuretics (e.g., bendroflumethiazide), which reach their tubular sites of action mainly by proximal tubular secretion. Previous experiments in Oat1 knockout (−/−) mice revealed an almost complete loss of renal secretion of the prototypic organic anion p-aminohippurate (PAH) and a role of OAT1 in tubular secretion of furosemide (Eraly SA, Vallon V, Vaughn D, Gangoiti JA, Richter K, Nagle M, Monte JC, Rieg T, Truong DM, Long JM, Barshop BA, Kaler G, Nigam SK. J Biol Chem 281: 5072–5083, 2006). In this study we found that both furosemide and bendroflumethiazide inhibited mOat1- and mOat3-mediated uptake of a labeled tracer in Xenopus oocytes injected with cRNA, consistent with their being substrates for mouse OAT1 and OAT3. Experiments in Oat3−/−mice revealed intact renal secretion of PAH, but the dose-natriuresis curves for furosemide and bendroflumethiazide were shifted to the right and urinary furosemide excretion was impaired similar to the defect in Oat1−/−mice. Thus, whereas OAT1 (in contrast to OAT3) is the classic basolateral PAH transporter of the proximal tubule, both OAT1 and OAT3 contribute similarly to normal renal secretion of furosemide and bendroflumethiazide, and a lack of either one is not fully compensated by the other. Although microarray expression analysis in the kidneys of Oat1−/−and Oat3−/−mice revealed somewhat altered expression of a small number of transport-related genes, none were common to both knockout models. When searching for polymorphisms involved in human diuretic responsiveness, it may be necessary to consider both OAT1 and OAT3, among other genes.
Emergence of Sustained Spontaneous Hyperactivity and Temporary Preservation of off Responses in Ganglion Cells of the Retinal Degeneration (rd1) Mouse
Authors: Stasheff Steven F.
Published: January 2008

Complex alterations in the anatomy of outer retinal pathways accompany photoreceptor degeneration in the rd1 mouse model of retinitis pigmentosa, whereas inner retinal neurons appear relatively preserved. However, the progressive loss of photoreceptor input likely alters the neural circuitry of the inner retina. This study investigated resulting changes in the activity of surviving ganglion cells. Multielectrode recording monitored spontaneous and light-evoked extracellular action potentials simultaneously from 30 to 90 retinal ganglion cells of wild-type ( wt) or rd1 mice. In rd1 mice, this activity evolves through three phases. First, normal spontaneous “waves” of correlated firing are seen at postnatal day 7 (P7) and last until shortly after eye opening. Second, at P14, full-field light flashes evoke reliable responses in many cells, with preferential preservation of off responses. These diminish as photoreceptor degeneration progresses. Third, once light-evoked responses have disappeared in early adulthood, surviving rd1 ganglion cells fire at a much higher spontaneous frequency than normal, sometimes in rhythmic bursts that are distinct from the developmental “waves.” This hyperactivity is sustained well into adulthood, for weeks after photoreceptors have disappeared. Thus striking alterations occur in inner retinal physiology as retinal degeneration progresses in the rd1 mouse. Blindness occurs in the face of sustained hyperactivity among ganglion cells, which remain viable for months despite this activity. On and off responses are differentially affected in early stages of degeneration. While the source of these changes remains to be learned, such features should be considered in designing more effective treatments for these disorders.
Analysis of Between-Trial and Within-Trial Neural Spiking Dynamics
Authors: Czanner Gabriela , Eden Uri T. , Wirth Sylvia , Yanike Marianna , Suzuki Wendy A. , Brown Emery N.
Published: January 2008

Recording single-neuron activity from a specific brain region across multiple trials in response to the same stimulus or execution of the same behavioral task is a common neurophysiology protocol. The raster plots of the spike trains often show strong between-trial and within-trial dynamics, yet the standard analysis of these data with the peristimulus time histogram (PSTH) and ANOVA do not consider between-trial dynamics. By itself, the PSTH does not provide a framework for statistical inference. We present a state-space generalized linear model (SS-GLM) to formulate a point process representation of between-trial and within-trial neural spiking dynamics. Our model has the PSTH as a special case. We provide a framework for model estimation, model selection, goodness-of-fit analysis, and inference. In an analysis of hippocampal neural activity recorded from a monkey performing a location-scene association task, we demonstrate how the SS-GLM may be used to answer frequently posed neurophysiological questions including, What is the nature of the between-trial and within-trial task-specific modulation of the neural spiking activity? How can we characterize learning-related neural dynamics? What are the timescales and characteristics of the neuron's biophysical properties? Our results demonstrate that the SS-GLM is a more informative tool than the PSTH and ANOVA for analysis of multiple trial neural responses and that it provides a quantitative characterization of the between-trial and withintrial neural dynamics readily visible in raster plots, as well as the less apparent fast (1–10 ms), intermediate (11–20 ms), and longer (>20 ms) timescale features of the neuron's biophysical properties.
Alterations of GABAA-Receptor Function and Allosteric Modulation During Development of Status Epilepticus
Authors: Feng Hua-Jun , Mathews Gregory C. , Kao Chris , Macdonald Robert L.
Published: January 2008

Partial limbic seizures in rodents induced by pilocarpine progress from stages I–II (mouth and facial movements; head nodding) to stage III (forelimb clonus) and then progress rapidly to stages IV–V (generalized limbic seizures; rearing, and rearing with falling) followed by status epilepticus (SE). Although limbic seizures in rodents are terminated by benzodiazepines, a group of γ-aminobutyric acid type A (GABAA)–receptor positive modulators, significant pharmacoresistance to benzodiazepines develops within minutes during SE. The alterations of GABAA-receptor function and allosteric modulation during development of SE are poorly understood. We induced seizures in juvenile rats by administration of lithium followed by pilocarpine, and whole cell recordings of miniature inhibitory postsynaptic currents (mIPSCs) were obtained from hippocampal dentate granule cells in brain slices. Compared with a sham-treated group, mIPSC amplitude was reduced and decay was accelerated at onset of the first occurrence of stage III (S3) seizures [S3(0)], resulting in a reduction in the total charge transfer at S3(0). Recovery of mIPSC amplitude and prolongation of mIPSC decay occurred 30 min after onset of S3 seizures [S3(30)]. The mIPSC frequency was not altered for S3(0) and S3(30) neurons compared with sham neurons. The net enhancement of total charge transfer by diazepam was smaller for S3(30) than that for sham and S3(0) neurons; however, the net reduction of total charge transfer by zinc was greater for S3(30) than that for sham and S3(0) neurons. These findings suggest that substantial plastic changes of GABAA-receptor function and allosteric modulation occur rapidly in neurons from juvenile animals during development of SE.
Phospholipase A2Activation Enhances Inhibitory Synaptic Transmission in Rat Substantia Gelatinosa Neurons
Authors: Liu Tao , Fujita Tsugumi , Nakatsuka Terumasa , Kumamoto Eiichi
Published: January 2008

Phospholipase A2(PLA2) activation enhances glutamatergic excitatory synaptic transmission in substantia gelatinosa (SG) neurons, which play a pivotal role in regulating nociceptive transmission in the spinal cord. By using melittin as a tool to activate PLA2, we examined the effect of PLA2activation on spontaneous inhibitory postsynaptic currents (sIPSCs) recorded at 0 mV in SG neurons of adult rat spinal cord slices by use of the whole cell patch-clamp technique. Melittin enhanced the frequency and amplitude of GABAergic and glycinergic sIPSCs. The enhancement of GABAergic but not glycinergic transmission was largely depressed by Na+channel blocker tetrodotoxin or glutamate-receptor antagonists (6-cyano-7-nitroquinoxaline-2,3-dione and/or dl-2-amino-5-phosphonovaleric acid) and also in a Ca2+-free Krebs solution. The effects of melittin on glycinergic sIPSC frequency and amplitude were dose-dependent with an effective concentration of ∼0.7 μM for half-maximal effect and were depressed by PLA2inhibitor 4-bromophenacyl bromide or aristolochic acid. The melittin-induced enhancement of glycinergic transmission was depressed by lipoxygenase inhibitor nordihydroguaiaretic acid but not cyclooxygenase inhibitor indomethacin. These results indicate that the activation of PLA2in the SG enhances GABAergic and glycinergic inhibitory transmission in SG neurons. The former action is mediated by glutamate-receptor activation and neuronal activity increase, possibly the facilitatory effect of PLA2activation on excitatory transmission, whereas the latter action is due to PLA2and subsequent lipoxygenase activation and is independent of extracellular Ca2+. It is suggested that PLA2activation in the SG could enhance not only excitatory but also inhibitory transmission, resulting in the modulation of nociception.
Social Modulation of Sequence and Syllable Variability in Adult Birdsong
Authors: Sakata Jon T. , Hampton Cara M. , Brainard Michael S.
Published: January 2008

Birdsong is a learned motor skill that is performed with a high degree of stereotypy in adult birds. Nevertheless, even in species where song “crystallizes” in a form that remains stable over time, there is residual variability. Such variability in well-learned skills is often construed as uncontrolled and irrelevant biological “noise.” However, studies in the zebra finch indicate that variability in one song feature—the structure of individual syllables—is actively regulated and may serve a function. When male zebra finches sing alone (undirected song), variability in syllable structure is elevated relative to when they sing to females in a courtship context (female-directed song). This elevated variability is actively introduced to premotor structures controlling syllable production by a forebrain-basal ganglia circuit. Here we test whether social modulation of song variability extends to syllable sequencing, a hierarchically distinct feature of song organization controlled by separate neural substrates from syllable structure. We use Bengalese finches as a model species because, unlike zebra finches, they typically retain substantial moment-by-moment variability in the sequencing of syllables in crystallized adult song. We first show social modulation of previously studied song features, including syllable structure and song tempo. We then demonstrate that variability in syllable sequencing is rapidly modulated by social context with greater variability present in undirected song. These data indicate that the nervous system exerts active control over variability at multiple levels of song organization and support the hypothesis that such variability in otherwise stable adult song serves a function.
Erratum to “Lower Bounds for Some Factorable Matrices”
Authors: Rhoades B. E. , Sen Pali
Published: January 2008

The purpose of this erratum is to correct both the mathematical and
typographical errors made in 2006.
Influence of Impeller Geometry on the Unsteady Flow in a Centrifugal Fan: Numerical and Experimental Analyses
Authors: Younsi M. , Bakir F. , Kouidri S. , Rey R.
Published: January 2008

The aim of this study is to evaluate the influence of design parameters on the unsteady flow in a forward-curved centrifugal fan and their impact on the aeroacoustic behavior. To do so, numerical and experimental studies have been carried out on four centrifugal impellers designed with various geometrical parameters. The same volute casing has been used to study these impellers. The effects on the unsteady flow behavior related to irregular blade spacing, blade count and radial distance between the impeller periphery and the volute tongue have been studied. The numerical simulations of the unsteady flow have been carried out using computational fluid dynamics (CFD) tools based on the unsteady Reynolds averaged Navier Stokes (URANS) approach. The study is focused on the unsteadiness induced by the aerodynamic interaction between the volute and the rotating impeller blades. In order to predict the acoustic pressure at far field, the unsteady flow variables provided by the CFD calculations have been used as inputs in the Ffowcs Williams-Hawkings equations (FW-H). The experimental part of this work concerns measurement of aerodynamic performance of the fans using a test bench built according to ISO 5801 (1997) standard. In addition to this, pressure microphones have been flush mounted on the volute tongue surface in order to measure the wall pressure fluctuations. The sound pressure level (SPL) measurements have been carried out in an anechoic room in order to remove undesired noise reflections. Finally, the numerical results have been compared with the experimental measurements and a correlation between the wall pressure fluctuations and the far field noise signals has been found.
The Progress on Genetic Analysis of Nasopharyngeal Carcinoma
Authors: Zhou Xiaofeng , Cui Jing , Macias Virgilia , Kajdacsy-Balla André A. , Ye Hui , Wang Jianguang , Rao P. Nagesh
Published: January 2008

Nasopharyngeal carcinoma (NPC) is a rare malignancy in most parts of the world, but is one of the most common cancers in Southeast Asia. Both genetic and environmental factors contribute to the tumorigenesis of NPC, most notably the consumption of certain salted food items and Epstein-Barr virus infection. This review will focus on the current progress of the genetic analysis of NPC (genetic susceptibilities and somatic alterations). We will review the current advances in genomic technologies and their shaping of the future direction of NPC research.
Effect of Fluid Shear Stress on Endocytosis of Heparan Sulfate and Low-density Lipoproteins
Authors: Barkefors Irmeli , Aidun Cyrus K. , Ulrika Egertsdotter E. M.
Published: January 2008

Hemodynamic stress is a critical factor in the onset of atherosclerosis such that reduced rates of shear stress occurring at regions of high curvature are more prone to disease. The level of shear stress has direct influence on the thickness and integrity of the glycocalyx layer. Here we show that heparan sulfate, the main component of the glycocalyx layer, forms an intact layer only on cell surfaces subjected to shear, and not under static conditions. Furthermore, receptor-mediated endocytosis of heparan sulfate and low-density liporoteins is not detectable in cells exposed to shear stress. The internalized heparan sulfate and low-density lipoproteins are colocalized as shown by confocal imaging.
Tumor Necrosis Factor-Alpha in Peripical Tissue Exudates of Teeth with Apical Periodontitis
Authors: Pezelj-Ribaric Sonja , Magašic Karolina , Prpic Jelena , Miletic Ivana , Karlovic Zoran
Published: January 2008

Aim.The aim of this study was to determine tumor necrosis factor-alpha (TNF-α) levels in periapical exudates and to evaluate their relationship with radiological findings.Methodology.Periapical exudates were collected from root canals of 60 single-rooted teeth using absorbent paper points. TNF-αlevels were determined by enzyme-linked immunosorbent assays. The samples were divided into three groups according to the periapical radiolucent area.Results.Nonparametric Kruskal-Wallis test revealed significant differences between TNF-αconcentrations in control group (40,57±28, 15 pg/mL) and group with larger radiolucent areas (2365,79±582, 95 pg/mL), as well as between control and canals with small radiolucent areas (507,66±278, 97) (P<.05).Conclusions.The levels of TNF-αincrease significantly in teeth with periapical pathosis, from smaller to bigger lesions. This research and its results have shown that objective analysis of the TNF-αlevels enables establishment of a relationship between different concentrations of TNF-αand different radiological changes.
Pro- and Anti-Inflammatory Cytokine Balance in Major Depression: Effect of Sertraline Therapy
Authors: Sutcigil Levent , Oktenli Cagatay , Musabak Ugur , Bozkurt Ali , Cansever Adnan , Uzun Ozcan , Sanisoglu S. Yavuz , Yesilova Zeki , Ozmenler Nahit , Ozsahin Aytekin , Sengul Ali
Published: January 2008

The specific associations between antidepressant treatment and alterations in the levels of cytokines remain to be elucidated. In this study, we aimed to explore the role of IL-2, IL-4, IL-12, TNF-α, TGF-β1, and MCP-1 in major depression and to investigate the effects of sertraline therapy. Cytokine and chemokine levels were measured at the time of admission and 8 weeks after sertraline treatment. Our results suggest that the proinflammatory cytokines (IL-2, IL-12, and TNF-α) and MCP-1 were significantly higher, whereas anti-inflammatory cytokines IL-4 and TGF-β1 were significantly lower in patients with major depression than those of healthy controls. It seems likely that the sertraline therapy might have exerted immunomodulatory effects through a decrease in the proinflammatory cytokine IL-12 and an increase in the anti-inflammatory cytokines IL-4 and TGF-β1. In conclusion, our results indicate that Th1-, Th2-, and Th3-type cytokines are altered in the depressed patients and some of them might have been corrected by sertraline treatment.
Estimating Nielsen Numbers on Wedge Product Spaces
Authors: Khamsemanan Nirattaya , Kim Seung Won
Published: January 2008

Let "Equation missing" be a self-map of a finite polyhedron that is an aspherical wedge product space "Equation missing". In this paper, we estimate the Nielsen number "Equation missing" of "Equation missing". In particular, we study some algebraic properties of the free products and then estimate Nielsen numbers on torus wedge surface with boundary, Klein bottle wedge surface with boundary, and torus wedge torus.
Thermal-Hydraulic System Codes in Nulcear Reactor Safety and Qualification Procedures
Authors: Petruzzi Alessandro , D'Auria Francesco
Published: January 2008

In the last four decades, large efforts have been undertaken to provide reliable thermal-hydraulic system codes for the analyses of transients and accidents in nuclear power plants. Whereas the first system codes, developed at the beginning of the 1970s, utilized the homogenous equilibrium model with three balance equations to describe the two-phase flow, nowadays the more advanced system codes are based on the so-called “two-fluid model” with separation of the water and vapor phases, resulting in systems with at least six balance equations. The wide experimental campaign, constituted by the integral and separate effect tests, conducted under the umbrella of the OECD/CSNI was at the basis of the development and validation of the thermal-hydraulic system codes by which they have reached the present high degree of maturity. However, notwithstanding the huge amounts of financial and human resources invested, the results predicted by the code are still affected by errors whose origins can be attributed to several reasons as model deficiencies, approximations in the numerical solution, nodalization effects, and imperfect knowledge of boundary and initial conditions. In this context, the existence of qualified procedures for a consistent application of qualified thermal-hydraulic system code is necessary and implies the drawing up of specific criteria through which the code-user, the nodalization, and finally the transient results are qualified.
Remote Synchronization Simulation of Onboard Crystal Oscillator for QZSS Using L1/L2/L5 Signals for Error Adjustment
Authors: Iwata Toshiaki , Imae Michito , Suzuyama Tomonari , Hashibe Yuji , Fukushima Satoshi , Iwasaki Akira , Kokubu Kenji , Tappero Fabrizio , Dempster Andrew G.
Published: January 2008

A new error adjustment method for remote synchronization of the onboard crystal oscillator for the quasi‐zenith satellite system (QZSS) using three different frequency positioning signals (L1/L2/L5) is proposed. The error adjustment method that uses L1/L2 positioning signals was demonstrated in the past. In both methods, the frequency‐dependent part and the frequency‐independent part were considered separately, and the total time information delay was estimated. By adopting L1/L2/L5, synchronization was improved by approximately 15% compared with that using L1/L2 and approximately 10% compared with that using L1/L5 and a synchronization error of less than 0.77 nanosecond was realized.
An Overview of Westinghouse Realistic Large Break LOCA Evaluation Model
Authors: Frepoli Cesare
Published: January 2008

Since the 1988 amendment of the 10 CFR 50.46 rule in 1988, Westinghouse has been developing and applying realistic or best-estimate methods to perform LOCA safety analyses. A realistic analysis requires the execution of various realistic LOCA transient simulations where the effect of both model and input uncertainties are ranged and propagated throughout the transients. The outcome is typically a range of results with associated probabilities. The thermal/hydraulic code is the engine of the methodology but a procedure is developed to assess the code and determine its biases and uncertainties. In addition, inputs to the simulation are also affected by uncertainty and these uncertainties are incorporated into the process. Several approaches have been proposed and applied in the industry in the framework of best-estimate methods. Most of the implementations, including Westinghouse, follow the Code Scaling, Applicability and Uncertainty (CSAU) methodology. Westinghouse methodology is based on the use of the WCOBRA/TRAC thermal-hydraulic code. The paper starts with an overview of the regulations and its interpretation in the context of realistic analysis. The CSAU roadmap is reviewed in the context of its implementation in the Westinghouse evaluation model. An overview of the code (WCOBRA/TRAC) and methodology is provided. Finally, the recent evolution to nonparametric statistics in the current edition of the W methodology is discussed. Sample results of a typical large break LOCA analysis for a PWR are provided.
Progress in Understanding and Sequencing the Genome ofBrassica rapa
Authors: Hong Chang Pyo , Kwon Soo-Jin , Kim Jung Sun , Yang Tae-Jin , Park Beom-Seok , Lim Yong Pyo
Published: January 2008

Brassica rapa, which is closely related toArabidopsis thaliana, is an important crop and a model plant for studying genome evolution via polyploidization. We report the current understanding of the genome structure ofB. rapaand efforts for the whole-genome sequencing of the species. The tribeBrassicaceae, which comprises ca. 240 species, descended from a common hexaploid ancestor with a basic genome similar to that ofArabidopsis. Chromosome rearrangements, including fusions and/or fissions, resulted in the present-day “diploid”Brassicaspecies with variation in chromosome number and phenotype. Triplicated genomic segments ofB. rapaare collinear to those ofA. thalianawith InDels. The genome triplication has led to an approximately 1.7-fold increase in theB. rapagene number compared to that ofA. thaliana. Repetitive DNA ofB. rapahas also been extensively amplified and has diverged from that ofA. thaliana. For its whole-genome sequencing, theBrassica rapaGenome Sequencing Project (BrGSP) consortium has developed suitable genomic resources and constructed genetic and physical maps. Ten chromosomes ofB. rapaare being allocated toBrGSP consortium participants, and each chromosome will be sequenced by a BAC-by-BAC approach. Genome sequencing ofB. rapawill offer a new perspective for plant biology and evolution in the context of polyploidization.
Backup Hydrogen Maser Steering System for Galileo Precise Timing Facility
Authors: Wang Qinghua , Rochat Pascal , Stehlin Xavier
Published: January 2008

Two hydrogen masers (HMs) are used in the Precise Timing Facility to provide the physical realization of Galileo System Time, insuring the extremely high short‐term stability required for the navigation functions. In order to allow a smooth switch over between backup and primary HMs, the “backup HM steering algorithm” is developed. This acquires the phase difference measured between two HMs, computes a steering correction, and generates the steering correction to the backup HM via a PicoStepper with a 0.1‐picosecond resolution. The algorithm design is based on outlier removal and a proportional‐integral filtering controller. To verify the steering operability and the loop performance, the overall backup HM steering system is simulated using real HM‐HM measurements, and with simulated anomalies (phase/frequency spikes, jumps, and drift).
Recent Advances in Cotton Genomics
Authors: Zhang Hong-Bin , Li Yaning , Wang Baohua , Chee Peng W.
Published: January 2008

Genome research promises to promote continued and enhanced plant genetic improvement. As a world's leading crop and a model system for studies of many biological processes, genomics research of cottons has advanced rapidly in the past few years. This article presents a comprehensive review on the recent advances of cotton genomics research. The reviewed areas include DNA markers, genetic maps, mapped genes and QTLs, ESTs, microarrays, gene expression profiling, BAC and BIBAC libraries, physical mapping, genome sequencing, and applications of genomic tools in cotton breeding. Analysis of the current status of each of the genome research areas suggests that the areas of physical mapping, QTL fine mapping, genome sequencing, nonfiber and nonovule EST development, gene expression profiling, and association studies between gene expression and fiber trait performance should be emphasized currently and in near future to accelerate utilization of the genomics research achievements for enhancing cotton genetic improvement.
Green Synthesis of Ag and Pd Nanospheres, Nanowires, and Nanorods Using Vitamin B2: Catalytic Polymerisation of Aniline and Pyrrole
Authors: Nadagouda Mallikarjuna N. , Varma Rajender S.
Published: January 2008

For the first time, we report green chemistry approach using vitamin B2 in the synthesis of silver (Ag) and palladium (Pd), nanospheres, nanowires, and nanorods at room temperature without using any harmful reducing agents, such as sodium borohydride (NaBH4) or hydroxylamine hydrochloride and any special capping or dispersing agent. Vitamin B2 was used as reducing agent as well as capping agent due to its high‐water solubility, biodegradability, and low‐toxicity compared with other reducing agents. The average particle size of nanoprticle was found to be Ag (average size 6.1±0.1 nm) and Pd (average size 4.1±0.1 nm) nanoparticles in ethylene glycol and Ag (average size 5.9±0.1 nm, and average size 6.1±0.1) nanoparticles in acetic acid and NMP, respectively. The formation of noble multiple shape nanostructures and their self assembly were dependent on the solvent employed for the preparation. When water was used as solvent media, Ag and Pd nanoparticles started to self‐assemble into rod‐like structures and in isopropanol Ag and Pd nanoparticles yielded wire‐like structures with a thickness in the range of 10 to 20 nm and several hundred microns in length. In acetone and acetonitrile medium, the Ag and Pd nanoparticles are self‐assembled into a regular pattern making nanorod structures with thicknesses ranging from 100 to 200 nm and lengths of a few microns. The so‐synthesized nanostructures were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive
X‐ray (EDX) analysis, and UV spectroscopy. The ensuing Ag and Pd nanoparticles catalyzed the reactions of aniline and pyrrole to generate polyaniline and polypyrrole nanofibers and may find various technological and biological applications. This single‐step greener approach is general and can be extended to other noble metals and transition metal oxides.
A Parametric Time Domain Method for Spectral Moment Estimation and Clutter Mitigation for Weather Radars
Authors: Nguyen Cuong M. , Moisseev Dmitri N. , Chandrasekar V.
Published: January 2008

A parametric time domain method (PTDM) for clutter mitigation and precipitation spectral moments’ estimation for weather radars is introduced. Use of PTDM allows for the simultaneous estimation of clutter and precipitation echo spectral moments. It is shown that this approach leads to accurate estimates of precipitation spectral moments in the presence of clutter. Based on simulations, the PTDM performance is evaluated and compared against the clutter spectral filtering technique. In this study special attention is paid to the cases of strong clutter contamination. Furthermore, both methods, the PTDM and spectral clutter filter, are illustrated using the Colorado State University–University of Chicago–Illinois State Water Survey (CSU–CHILL) observations.
Simulated Doppler Radar Observations of Inhomogeneous Clouds: Application to the EarthCARE Space Mission
Authors: Schutgens N. A. J.
Published: January 2008

A new simulation technique for spaceborne Doppler radar observations that was developed specifically for inhomogeneous targets is presented. Cloud inhomogeneity affects Doppler observations in two ways. First, line-of-sight velocities within the instantaneous field of view are unequally weighted. As the large forward motion of a spaceborne radar contributes to these line-of-sight velocities this causes biases in observed Doppler speeds. Second, receiver voltages now have time-varying stochastical properties, increasing the inaccuracy of Doppler observations. The new technique predicts larger inaccuracies of observed Doppler speeds than the traditional random signal simulations based on the inverse Fourier transform.

The accuracy of Doppler speed observations by a spaceborne 95-GHz radar [as part of the proposed European Space Agency (ESA)/Japan Aerospace Exploration Agency (JAXA)/National Institute for Information and Communications Technology (NICT) EarthCARE mission] is assessed through simulations for realistic cloud scenes based on observations made by ground-based cloud-profiling radars. Close to lateral cloud boundary biases as large as several meters per second occur. For half of the cloud scenes investigated, the distribution of the in-cloud bias has an rms of 0.5 m s−1, implying that a bias in excess of 0.5 m s−1 will not be uncommon.

An algorithm to correct the bias in observed Doppler observations, based on the observed gradient of reflectivity along track, is suggested and shown to be effective; that is, the aforementioned rms bias reduces to 0.14 m s−1.
Feature Extraction from Whole-Sky Ground-Based Images for Cloud-Type Recognition
Authors: Calbó Josep , Sabburg Jeff
Published: January 2008

Several features that can be extracted from digital images of the sky and that can be useful for cloud-type classification of such images are presented. Some features are statistical measurements of image texture, some are based on the Fourier transform of the image and, finally, others are computed from the image where cloudy pixels are distinguished from clear-sky pixels. The use of the most suitable features in an automatic classification algorithm is also shown and discussed. Both the features and the classifier are developed over images taken by two different camera devices, namely, a total sky imager (TSI) and a whole sky imager (WSC), which are placed in two different areas of the world (Toowoomba, Australia; and Girona, Spain, respectively). The performance of the classifier is assessed by comparing its image classification with an a priori classification carried out by visual inspection of more than 200 images from each camera. The index of agreement is 76% when five different sky conditions are considered: clear, low cumuliform clouds, stratiform clouds (overcast), cirriform clouds, and mottled clouds (altocumulus, cirrocumulus). Discussion on the future directions of this research is also presented, regarding both the use of other features and the use of other classification techniques.
Impact of Resolution and Optimized ECCO Forcing on Simulations of the Tropical Pacific
Authors: Hoteit I. , Cornuelle B. , Thierry V. , Stammer D.
Published: January 2008

The sensitivity of the dynamics of a tropical Pacific Massachusetts Institute of Technology (MIT) general circulation model (MITgcm) to the surface forcing fields and to the horizontal resolution is analyzed. During runs covering the period 1992–2002, two different sets of surface forcing boundary conditions are used, obtained 1) from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis project and 2) from the Estimating the Circulation and Climate of the Ocean (ECCO) assimilation consortium. The “ECCO forcing” is the “NCEP forcing” adjusted by a state estimation procedure using the MITgcm with a 1° × 1° global grid and the adjoint method assimilating a multivariate global ocean dataset. The skill of the model is evaluated against ocean observations available in situ and from satellites. The model domain is limited to the tropical Pacific, with open boundaries located along 26°S, 26°N, and in the Indonesian throughflow. To account for large-scale changes of the ocean circulation, the model is nested in the global time-varying ocean state provided by the ECCO consortium on a 1° grid. Increasing the spatial resolution to 1/3° and using the ECCO forcing fields significantly improves many aspects of the circulation but produces overly strong currents in the western model domain. Increasing the resolution to 1/6° does not yield further improvements of model results. Using the ECCO heat and freshwater fluxes in place of NCEP products leads to improved time-mean model skill (i.e., reduced biases) over most of the model domain, underlining the important role of adjusted heat and freshwater fluxes for improving model representations of the tropical Pacific. Combinations of ECCO and NCEP wind forcing fields can improve certain aspects of the model solutions, but neither ECCO nor NCEP winds show clear overall superiority.
More Eyes on the Prize: Variability in White Americans' Perceptions of Progress Toward Racial Equality
Authors: Brodish Amanda B. , Brazy Paige C. , Devine Patricia G.
Published: January 2008

Much recent research suggests that Whites and non-Whites think differently about issues of race in contemporary America. For example, Eibach and Ehrlinger (2006) recently demonstrated that Whites perceive that more progress toward racial equality has been made as compared to non-Whites. The authors of this article sought to extend Eibach and Ehrlinger's analysis. To this end, they found that differences in Whites' and non-Whites' perceptions of racial progress can be explained by the reference points they use for understanding progress toward racial equality (Study 1). Furthermore, they demonstrated that there is variability in White people's perceptions of racial progress that can be explained by self-reported racial prejudice (Studies 1 and 2). Finally, they demonstrated that White people's perceptions of racial progress predict reactions to affirmative action (Study 2). Implications for better understanding intergroup relations and reactions to social policies are discussed.
Photoencapsulation of Bone Morphogenetic Protein-2 and Periosteal Progenitor Cells Improve Tendon Graft Healing in a Bone Tunnel
Authors: Chen Chih-Hwa , Liu Hsia-Wei , Tsai Ching-Lin , Yu Chung-Ming , Lin I-Hsuan , Hsiue Ging-Ho
Published: January 2008

Background

Tissue-engineered solutions for promoting the tendon graft incorporation within the bone tunnel appear to be promising.

Hypothesis

To determine the feasibility that conjugation of hyaluronic acid-tethered bone morphogenetic protein-2 can be used to stimulate periosteal progenitor cells direct fibrocartilagenous attachment and new bone formation in an extra-articular tendon-bone healing model.

Study Design

Controlled laboratory study.

Methods

A total of 42 mature New Zealand White rabbits were used. The long digitorum extensor tendon was transplanted into a bone tunnel of the proximal tibia. The tendon was pulled through a drill hole in the proximal tibia and attached to the medial aspect of the tibia. Photopolymerizable hydrogel based on poly (ethylene glycol) diacrylate with hyaluronic acid-tethered bone morphogenetic protein-2 was injected and photogelated in a bone tunnel. Histological and biomechanical examination of the tendon-bone interface was evaluated at postoperative weeks 3 and 6.

Results

Histological analysis showed an interface fibrocartilage and new bone formed by photoencapsulation of bone morphogenetic protein-2 and periosteal progenitor cells at 6 weeks. Biomechanical testing revealed higher maximum pullout strength and stiffness in experimental groups with a statistically significant difference at 3 and 6 weeks after tendon transplantation.

Conclusion

The healing tendon-bone interface undergoes a gradual remodeling process; it appears that photoencapsulation of bone morphogenetic protein-2 and periosteal progenitor cells possesses a powerful inductive ability between the tendon and the bone to incorporate the healing in a rabbit model.

Clinical Relevance

Novel technologies, such as those described in this study, including photopolymerization and tissue engineering, may provide minimally invasive therapeutic procedures via arthroscopy to enhance biological healing after reconstruction of the anterior cruciate ligament.