bluuebunny/crossref_metadata_2025 huggingface dataset:
PIXE–RBS survey of a Meissen porcelain snuff box: first version or not?
Authors: Neelmeijer C. , Roscher R.
Published: January 2012

Non‐destructive materials analysis provided essential knowledge for deciding on the complete authenticity of a unique work of art made from porcelain, rich of delicate painting. The combination of ion‐beam based methods proton‐induced X‐ray emission (PIXE) and Rutherford‐backscattering spectrometry (RBS) was able to make simultaneously available both bulk composition and surface characterization. Potential differences in glazing and painting materials were verified when examining the base body and the lid of the box. In particular, RBS from Pb atoms in the near‐surface depth region could identify lead‐glazing for the shaded porcelain of the bottom. The chemical composition of the brilliant glaze of the lid was proved by PIXE to conform to the typical Meissen recipe. Consequently, a later completed or restored object was deduced. Copyright © 2012 John Wiley & Sons, Ltd.
Heavy flavor simplified models at the LHC
Authors: Essig Rouven , Izaguirre Eder , Kaplan Jared , Wacker Jay G.
Published: January 2012

Abstract

We consider a comprehensive set of simplified models that contribute to final states with top and bottom quarks at the LHC. These simplified models are used to create minimal search strategies that ensure optimal coverage of new heavy flavor physics involving the pair production of color octets and triplets. We provide a set of benchmarks that are representative of model space, which can be used by experimentalists to perform their own optimization of search strategies. For data sets larger than 1 fb−1, same-sign dilepton and 3b search regions become very powerful. Expected sensitivities from existing and optimized searches are given.
Surgical Options for Recalcitrant Carpal Tunnel Syndrome with Perineural Fibrosis
Authors: Abzug Joshua M. , Jacoby Sidney M. , Osterman A. Lee
Published: January 2012

Surgical release of the transverse carpal ligament for the treatment of carpal tunnel syndrome (CTS) is, in general, a very successful procedure. Some patients, however, fail this standard release and have persistent or recurrent symptoms. Such recalcitrance may relate to incomplete release but more often relates to perineural or intraneural fibrosis of the median nerve. While there is no good treatment for intraneural fibrosis, numerous procedures have evolved in an attempt to treat perineural fibrosis which restricts nerve gliding. These include procedures to isolate the nerve from scar as well as procedures to bring neovascularization to the median nerve. This review describes the various surgical treatment options for recalcitrant CTS as well as their reported outcomes.
Verification of the interdomain contact site in the inactive monomer, and the domain‐swapped fold in the active dimer of Hsp33 in solution
Authors: Lee Yoo-Sup , Ryu Kyoung-Seok , Kim Seo-Jin , Ko Hyun-Suk , Sim Dae-Won , Jeon Young Ho , Kim Eun-Hee , Choi Wahn-Soo , Won Hyung-Sik
Published: January 2012

Upon dimerization by oxidation, Hsp33 functions as a molecular chaperone in prokaryotes. Previously published structures of both the inactive and active species are of doubtful relevance to the solution conformations since the inactive (reduced) crystal structure was dimeric, while the active (oxidized) species was crystallized with a truncation of its regulation domain. The interdomain contact site of the inactive monomer, identified in this work, is consistent with that previously observed in the reduced dimer crystal. In contrast, fluorescence quenching of the active dimer contradicted the results expected from the domain‐swapped fold observed in the truncated dimer crystal. The results of this study provide important new information concerning controversial issues in the activation process of Hsp33.
Perinatal outcomes associated with subsequent pregnancy among adolescent mothers in Peru
Authors: Ventura Walter , Ventura‐Laveriano Jessica , Nazario‐Redondo Conny
Published: January 2012

Objective

To assess the perinatal outcomes of a subsequent pregnancy among adolescent mothers living in Peru.

Methods

A large hospital‐based retrospective cohort study was conducted to evaluate singleton births during a 9‐year period (2001–2009). The study population was divided into 3 groups: adolescents aged 15–19 years who had 1 previous parturition (n = 2074), nulliparous adolescents (n = 20 721), and multiparous adults aged 20–29 years (n = 23 129).

Results

No significant differences were found between multiparous adolescents and the 2 control groups with regard to preterm delivery, perinatal death, and 5‐minute Apgar score below 7. Logistic regression analysis showed no significant differences in the rates of cesarean delivery or preterm birth before 34 or 37 weeks. After adjusting for confounding factors, low birth weight (LBW) and small for gestational age (SGA) were more likely to occur during a subsequent pregnancy among adolescent mothers than during the 1st pregnancy among nulliparous adolescents. The odds ratios were 1.38 (95% CI, 1.14–1.67) and 1.27 (95% CI, 1.02–1.56), respectively.

Conclusion

Multiparous adolescents are more likely to experience LBW or SGA than are nulliparous adolescents. No significant differences in other perinatal outcomes were found among the 3 study groups.
Evaluation of the biocompatibility of a coating material for an implantable bladder volume sensor
Authors: Kim Su‐Jin , Lee Dong‐Sup , Kim In‐Gul , Sohn Dong‐Wan , Park Jung‐Yul , Choi Bum‐Kyoo , Kim Sae‐Woong
Published: January 2012

As the applications for implantable medical devices have increased, the need for biocompatible packaging materials has become important. Recently, we reported an implantable sensor for real‐time monitoring of the changes in bladder volume, which necessitated finding a safe coating material for use in bladder tissue. At present, materials like polyethylene glycol (PEG), polydimethylsiloxane (PDMS) and parylene‐C are used in biomedical devices or as coating materials, owing to their excellent safety in various medical fields. However, few studies have assessed their safety in bladder tissue, therefore, we evaluated the biocompatibility of PEG, PDMS and parylene‐C in the bladder. All three materials turned out to be safe in in vitro tests of live/dead staining and cell viability. In vivo tests with hematoxylin and eosin and immunofluorescence staining with MAC387 showed no persistent inflammation. Therefore, we consider that the three materials are biocompatible in bladder tissue. Despite this safety, however, PEG has biodegradable characteristics and thus is not suitable for use as packaging. We suggest that PDMS and parylene‐C can be used as safe coating materials for the implantable bladder volume sensor reported previously.
Sedimentation of a sphere in a viscoelastic fluid: a multiscale simulation approach
Authors: Abedijaberi A. , Khomami B.
Published: January 2012

A long-standing problem in non-Newtonian fluid mechanics, namely the relationship between drag experienced by a sphere settling in a tube filled with a dilute polymeric solution and the sphere sedimentation velocity, is investigated via self-consistent multiscale flow simulations. Comparison with experimental measurements by Arigo et al. (J. Non-Newtonian Fluid Mech., vol. 60, 1995, pp. 225–257) have revealed that the evolution of the drag coefficient as a function of fluid elasticity can be accurately predicted when the macromolecular dynamics is described by realistic micromechanical models that closely capture the transient extensional viscosity of the experimental fluid at high extension rates. Specifically, for the first time we have computed the drag coefficient on the sphere at high Weissenberg number $\mathit{Wi}$ utilizing multi-segment bead–spring chain models with appropriate molecular parameters and have demonstrated that a hi-fidelity multiscale simulation is not only capable of accurately describing the drag on the sphere as a function of $\mathit{Wi}$ at various sphere-to-tube diameter ratios but also it can closely reproduce the experimentally observed velocity and stresses in the wake of the sphere.
SOWING STRATEGIES FOR BARLEY (HORDEUM VULGARE L.) BASED ON MODELLED YIELD RESPONSE TO WATER WITH AQUACROP
Authors: ABRHA BERHANU , DELBECQUE NELE , RAES DIRK , TSEGAY ALEMTSEHAY , TODOROVIC MLADEN , HENG LEE , VANUTRECHT ELINE , GEERTS SAM , GARCIA-VILA MARGA , DECKERS SEPPE
Published: January 2012

AquaCrop, the FAO water productivity model, is used as a tool to predict crop production under water limiting conditions. In the first step AquaCrop was calibrated and validated for barley (Hordeum vulgare L.). Data sets of field experiments at seven different locations in four countries (Ethiopia, Italy, Syria and Montana, USA) with different climates in different years and with five different cultivars were used for model calibration and validation. The goodness-of-fit between observed and simulated soil water content, green canopy cover, biomass and grain yield was assessed by means of the coefficient of determination (R2), the Nash–Sutcliff efficiency (E), the index of agreement (d) and the root mean square error (RMSE). The statistical parameters indicated an adequate accuracy of simulations (validation regression of yield: R2 = 0.95, E = 0.94, d = 0.99, RMSE = 0.34). Subsequently, sowing strategies in the semi-arid environment of northern Ethiopia were evaluated with the validated model. Dry sowing had a probability of 47% germination failure attributable to false start of the rainy season. On the other hand, delay sowing at the start of the rainy season to eliminate germinating weeds should be kept as short as possible because grain yields strongly reduce in the season due to water stress when sowing is delayed on shallow soils. This research demonstrates the ability of AquaCrop to predict accurately crop performance with only a limited set of input variables, and the robustness of the model under various environmental and climatic conditions.
Clean Sweep: Informed Trading through Intermarket Sweep Orders
Authors: Chakravarty Sugato , Jain Pankaj , Upson James , Wood Robert
Published: January 2012

An intermarket sweep order (ISO) is a limit order that automatically executes in a designated market center even if another market center is publishing a better quotation. An investor submitting an ISO must satisfy order protection rules by concurrently submitting orders to the markets with better prices. We find that ISOs represent 46% of trades and 41% of volume in our sample. ISO trades have a significantly larger information share despite their small trade size relative to non-ISO trades. Post trade return analysis suggests that informed institutions are the main users of ISO trades.
Form and Meaning in Etruscan Ritual Space
Authors: Izzet Vedia E.
Published: January 2012

Monumental sanctuaries in Central Italy, more specifically South Etruria, appear suddenly in the middle of the first millennium bc. Ancient Greek and Roman authors wrote about the Etruscans, and the Etruscans themselves produced a mass of material evidence which they buried in their tombs, and which drew on Classical elements including mythology. As a result of the wealth and breadth of archaeological material, this society provides much, so far unexplored, scope for cognitive investigation. Here my concern is why sanctuaries emerged in the late sixth century, and why the highly codified temple architecture of South Etruria took the form that it did.
The last major Irish bank failure before 2008
Authors: Gráda Cormac Ó
Published: January 2012

Until 2008, Ireland's banks had a solid reputation. Its two long-established banks could trace their origins back to the beginnings of joint-stock banking in 1825. Few banks of consequence had failed in the interim. The last such failure, the focus of this article, was that of the Munster Bank in 1885. That event tells us much about the history of Irish banking before recent events.
A Transmission Electron Microscopy Study of the Effect of Interfaces on Bubble Formation in He-Implanted Cu-Nb Multilayers
Authors: Bhattacharyya D. , Demkowicz M.J. , Wang Y.-Q. , Baumer R.E. , Nastasi M. , Misra A.
Published: January 2012

Magnetron sputtered thin films of Cu, Nb, and Cu-Nb multilayers with 2.5 and 5 nm nominal layer thickness were deposited on Si and implanted with 4He+ and 3He+ ions. Secondary ion mass spectroscopy and nuclear reaction analysis, respectively, were used to measure the 4He+ and 3He+ concentration profile with depth inside the films. Cross-sectional transmission electron microscopy was used to characterize the helium bubbles. Analysis of the contrast from helium bubbles in defocused transmission electron microscope images showed a minimum bubble diameter of 1.25 nm. While pure Cu and Nb films showed bubble contrast over the entire range of helium implantation, the multilayers exhibited bubbles only above a critical He concentration that increased almost linearly with decreasing layer thickness. The work shows that large amounts of helium can be trapped at incoherent interfaces in the form of stable, nanometer-size bubbles.
Phase Contrast Synchrotron Microtomography: Improving Noninvasive Investigations of Fossil Embryos In Ovo
Authors: Fernandez Vincent , Buffetaut Eric , Maire Eric , Adrien Jérôme , Suteethorn Varavudh , Tafforeau Paul
Published: January 2012

Fossil embryos are paramount for our understanding of the development of extinct species. However, although thousands of fossil amniote eggs are known, very few embryos in ovo have been described. First reports of fossil embryos were based on broken eggs, where the embryonic remains were already exposed, because destructive methods on complete eggs were avoided. Investigations of complete eggs therefore required nondestructive approaches, such as X-ray microtomography (μCT). However, due to the general low density contrast between fossilized bones and infilling matrix, only a few specimens have been reported using these techniques. Using propagation phase contrast X-ray synchrotron microtomography (PPC-SR-μCT), we report here the discovery of three well-preserved embryos in Early Cretaceous eggs from Thailand. By scanning these eggs using different imaging techniques, we show that vastly different interpretations can be made regarding the preservation state and/or the developmental stage of these embryos. PPC-SR-μCT also revealed differential contrast between bone categories, presumably reflecting the ossification pattern of these embryos. Applying such an approach to large-scale studies of fossil eggs could lead to more discoveries and detailed studies of fossil embryos, providing important developmental and phylogenetic information on extinct and extant amniotes.
Examination of a Polycrystalline Thin-Film Model to Explore the Relation between Probe Size and Structural Correlation Length in Fluctuation Electron Microscopy
Authors: Treacy M.M.J. , Gibson J.M.
Published: January 2012

We examine simulated electron microdiffraction patterns from models of thin polycrystalline silicon. The models are made by a Voronoi tessellation of random points in a box. The Voronoi domains are randomly selected to contain either a randomly-oriented cubic crystalline grain or a region of continuous random network material. The microdiffraction simulations from coherent probes of different widths are computed at the ideal kinematical limit, ignoring inelastic and multiple scattering. By examining the normalized intensity variance that is obtained in fluctuation electron microscopy experiments, we confirm that intensity fluctuations increase monotonically with the percentage of crystalline grains in the material. However, anomalously high variance is observed for models that have 100% crystalline grains with no imperfections. We confirm that the reduced normalized variance,V(k,R) − 1, that is associated with four-body correlations at scattering vectork, varies inversely with specimen thickness. Further, for probe sizesRlarger than the mean grain size, we confirm that the reduced normalized variance obeys the predicted form given by Gibson et al. [Ultramicroscopy,83, 169–178 (2000)] for the kinematical coherent scattering limit.
Improving Accuracy and Precision of Strain Analysis by Energy-Filtered Nanobeam Electron Diffraction
Authors: Hähnel Angelika , Reiche Manfred , Moutanabbir Oussama , Blumtritt Horst , Geisler Holm , Höntschel Jan , Engelmann Hans-Jürgen
Published: January 2012

This article deals with uncertainty in the analysis of strain in silicon nanoscale structures and devices using nanobeam electron diffraction (NBED). Specimen and instrument related errors and instabilities and their effects on NBED analysis are addressed using a nanopatterned ultrathin strained silicon layer directly on oxide as a model system. We demonstrate that zero-loss filtering significantly improves the NBED precision by decreasing the diffuse background in the diffraction patterns. To minimize the systematic deviations the acquired data were verified through a reliability test and then calibrated. Furthermore, the effect of strain relaxation by specimen preparation using a FIB is estimated by comparing profiles, which were acquired by analyzing slices of strained structures in a 220-nm-thick region of the sample (invasive preparation) and the entire strained nanostructures, which are embedded in a thicker region of the same sample (noninvasive preparation). Together with the random deviation, the corresponding systematic shift results in a total deviation of ∼1 × 10−3for NBED analyses, which is employed to estimate the measurement uncertainty in the thinner sample region. In contrast, the strain in the thick sample region is not affected by the preparation; the systematic shift reduces to a minimum, which improves the total deviation by ∼50%.
The Glomerular Basement Membrane as a Model System to Study the Bioactivity of Heparan Sulfate Glycosaminoglycans
Authors: McCarthy Kevin J. , Wassenhove-McCarthy Deborah J.
Published: January 2012

The glomerular basement membrane and its associated cells are critical elements in the renal ultrafiltration process. Traditionally the anionic charge associated with several carbohydrate moieties in the glomerular basement membrane are thought to form a charge selective barrier that restricts the transmembrane flux of anionic proteins across the glomerular basement membrane into the urinary space. The charge selective function, along with the size selective component of the basement membrane, serves to limit the efflux of plasma proteins from the capillary lumen. Heparan sulfate glycosaminoglycans are anionically charged carbohydrate structures attached to proteoglycan core proteins and have a role in establishing the charge selective function of the glomerular basement membrane. Although there are a large number of studies in the literature that support this concept, the results of several recent studies using molecular genetic approaches to minimize the anionic charge of the glomerular basement membrane would suggest that the role of heparan sulfate glycosaminoglycans in the glomerular capillary wall are still not yet entirely resolved, suggesting that this research area still requires new and novel exploration.
Quantitative Mineralogical Properties (Morphology-Chemistry-Structure) of Pharmaceutical Grade Kaolinites and Recommendations to Regulatory Agencies
Authors: Dogan Meral , Dogan A. Umran , Aburub Aktham , Botha Alta , Wurster Dale Eric
Published: January 2012

The physical and chemical characteristics of kaolinite (kaolin) may be variable, and minor amounts of other clay minerals, nonclay minerals, and other impurities may affect the properties of kaolinites. Thus specific technical properties of pharmaceutical grade kaolinites become very important because these clays are used in medical applications, e.g., as pharmaceutical excipients, and will be consumed by humans. Seven pharmaceutical grade kaolinite specimens were used in this study: K1004, KA105, 2242-01, K2-500, Acros, Acros-mono, and KX0007-1. In addition, two kaolinites from the Clay Minerals Society Source Clays, KGa-1b and KGa-2, were used for comparison purposes. The Acros-mono and 2242-01 kaolinites contained minor amounts of illite, which was demonstrated both compositionally and structurally by using inductively coupled plasma spectroscopy and powder X-ray diffraction. The KX0007-1 kaolinite powder was found to be heavily contaminated with quartz, cristobalite, and alunite. Crystal structure computations also showed excess Si in its tetrahedral site, and the mineral no longer has the typical kaolinite crystal structure. These widely-used industrial standards should be quantitatively characterized morphologically, compositionally, and structurally. Results of the mineralogical characteristics should be clearly labeled on the pharmaceutical grade kaolinites and reported to the relevant regulatory agencies.
Introduction: Extracellular Matrix and Cardiovascular Remodeling—Using Microscopy to Delineate Mechanisms
Authors: Lindsey Merry L. , Borg Thomas K.
Published: January 2012

In January 2011, a Keystone Symposium on “Extracellular Matrix and Cardiovascular Remodeling” was held in Tahoe City, California. The purpose of this meeting was to focus on the general theme of extracellular matrix (ECM) roles in cardiovascular remodeling. The presentations and discussions stimulated by this meeting, which was attended by approximately 160 people, serve as the inspiration for this special section of Microscopy and Microanalysis.
Effects of foliage clumping on the estimation of global terrestrial gross primary productivity
Authors: Chen Jing M. , Mo Gang , Pisek Jan , Liu Jane , Deng Feng , Ishizawa Misa , Chan Douglas
Published: January 2012

Sunlit and shaded leaf separation proposed by Norman (1982) is an effective way to upscale from leaf to canopy in modeling vegetation photosynthesis. The Boreal Ecosystem Productivity Simulator (BEPS) makes use of this methodology, and has been shown to be reliable in modeling the gross primary productivity (GPP) derived from CO2flux and tree ring measurements. In this study, we use BEPS to investigate the effect of canopy architecture on the global distribution of GPP. For this purpose, we use not only leaf area index (LAI) but also the first ever global map of the foliage clumping index derived from the multiangle satellite sensor POLDER at 6 km resolution. The clumping index, which characterizes the degree of the deviation of 3‐dimensional leaf spatial distributions from the random case, is used to separate sunlit and shaded LAI values for a given LAI. Our model results show that global GPP in 2003 was 132 ± 22 Pg C. Relative to this baseline case, our results also show: (1) global GPP is overestimated by 12% when accurate LAI is available but clumping is ignored, and (2) global GPP is underestimated by 9% when the effective LAI is available and clumping is ignored. The clumping effects in both cases are statistically significant (p < 0.001). The effective LAI is often derived from remote sensing by inverting the measured canopy gap fraction to LAI without considering the clumping. Global GPP would therefore be generally underestimated when remotely sensed LAI (actually effective LAI by our definition) is used. This is due to the underestimation of the shaded LAI and therefore the contribution of shaded leaves to GPP. We found that shaded leaves contribute 50%, 38%, 37%, 39%, 26%, 29% and 21% to the total GPP for broadleaf evergreen forest, broadleaf deciduous forest, evergreen conifer forest, deciduous conifer forest, shrub, C4 vegetation, and other vegetation, respectively. The global average of this ratio is 35%.
Detection of exospheric O2+ at Saturn's moon Dione
Authors: Tokar R. L. , Johnson R. E. , Thomsen M. F. , Sittler E. C. , Coates A. J. , Wilson R. J. , Crary F. J. , Young D. T. , Jones G. H.
Published: January 2012

During a close pass of Cassini through the plasma wake of Saturn's moon Dione on April 7, 2010 the Cassini Plasma Spectrometer (CAPS) detected molecular oxygen ions (O2+) on pick up ring velocity distributions, thus providing the first in situ detection of a neutral exosphere surrounding the icy moon. The density of O2+ determined from the CAPS data ranges from 0.01 to 0.09 /cm3 and is used to estimate the exosphere O2 radial column density, obtaining the range 0.9 to 7 × 1011/cm2 . CAPS was unable to directly detect pick up H2O+ from the exosphere but the observations can be used to set an upper limit to their density of ∼10 times the O2+ density.
The genesis of an inter‐field marine sandwave and the associated anti‐asymmetry migration of neighboring crests
Authors: Hanes Daniel M.
Published: January 2012

A series of high resolution multibeam echo sounding surveys near San Francisco, CA suggests the occasional migration of marine sandwave crests in the direction opposite to that indicated by the shape asymmetry of the individual sandwaves, in contrast to all previous observations of the relationship between bedform shape asymmetry and migration. The anti‐asymmetry migration occurs over approximately the same time period that a new sand wave crest is formed within the large and relatively stable field. The new sandwave crest appears approximately midway between two larger crests, in the vicinity of structural defects in a nearly two‐dimensional portion of the field. The sandwaves in the vicinity of the new crest are found to have migrated away from the new crest regardless of their shape asymmetry. Later a large section of the new crest disappears, and the neighboring sandwaves migrated back toward the vacated crest location. This migration occurs for sandwaves up to at least ten wavelengths away from the new crest.
Relative permeability and trapping of CO2 and water in sandstone rocks at reservoir conditions
Authors: Krevor Samuel C. M. , Pini Ronny , Zuo Lin , Benson Sally M.
Published: January 2012

We report the results of an experimental investigation into the multiphase flow properties of CO2 and water in four distinct sandstone rocks: a Berea sandstone and three reservoir rocks from formations into which CO2 injection is either currently taking place or is planned. Drainage relative permeability and residual gas saturations were measured at 50°C and 9 MPa pore pressure using the steady state method in a horizontal core flooding apparatus with fluid distributions observed using x‐ray computed tomography. Absolute permeability, capillary pressure curves, and petrological studies were performed on each sample. Relative permeability in the four samples is consistent with general characteristics of drainage in strongly water‐wet rocks. Measurements in the Berea sample are also consistent with past measurements in Berea sandstones using both CO2/brine and oil/water fluid systems. Maximum observed saturations and permeabilities are limited by the capillary pressure that can be achieved in the experiment and do not represent endpoint values. It is likely that maximum saturations observed in other studies are limited in the same way and there is no indication that low endpoint relative permeabilities are a characteristic of the CO2/water system. Residual trapping in three of the rocks is consistent with trapping in strongly water‐wet systems, and the results from the Berea sample are again consistent with observations in past studies. This confirms that residual trapping can play a major role in the immobilization of CO2 injected into the subsurface. In the Mt. Simon sandstone, a nonmonotonic relationship between initial and residual CO2 saturations is indicative of a rock that is mixed or intermediate wet, and further investigations should be performed to establish the wetting properties of illite‐rich rocks. The combined results suggest that the petrophysical properties of the multiphase flow of CO2/water through siliciclastic rocks is for the most part typical of a strongly water‐wet system and that analog fluids and conditions may be used to characterize these properties. Further investigation is required to identify the wetting properties of illite‐rich rocks during imbibition processes.
Diffusion of floating particles in flow through emergent vegetation: Further experimental investigation
Authors: Defina Andrea , Peruzzo Paolo
Published: January 2012

In this paper we present the results of a new laboratory investigation aimed at providing a better understanding of the transport and diffusion processes of floating particles (e.g., buoyant seeds) in open channel flow with emergent vegetation. The experiments are designed primarily to study the influence of vegetation density and flow velocity on the relevant interaction mechanisms between particles and vegetation. The aim is also to ascertain the validity of a stochastic model recently proposed by Defina and Peruzzo (2010). We find that (1) the proper definition of plant spacing is given as 1/npdp, with dp being the plant diameter and np being the number of plants per unit area, (2) the particle retention time distribution can be satisfactorily approximated by a weighted combination of two exponential distributions, (3) flow velocity has a significant influence on the retention time and on the efficiency of the different trapping mechanisms, and (4) vegetation pattern and density have a minor influence on the probability of capture and on the retention time of particles. Indeed, the comparison between model predictions and experimental results is satisfactory and suggests that the observed relevant aspects of the particle‐vegetation interaction processes are properly described by the model.
Stem Cell Therapy for Cerebral Ischemia: From Basic Science to Clinical Applications
Authors: Abe Koji , Yamashita Toru , Takizawa Shunya , Kuroda Satoshi , Kinouchi Hiroyuki , Kawahara Nobutaka
Published: January 2012

Recent stem cell technology provides a strong therapeutic potential not only for acute ischemic stroke but also for chronic progressive neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis with neuroregenerative neural cell replenishment and replacement. In addition to resident neural stem cell activation in the brain by neurotrophic factors, bone marrow stem cells (BMSCs) can be mobilized by granulocyte-colony stimulating factor for homing into the brain for both neurorepair and neuroregeneration in acute stroke and neurodegenerative diseases in both basic science and clinical settings. Exogenous stem cell transplantation is also emerging into a clinical scene from bench side experiments. Early clinical trials of intravenous transplantation of autologous BMSCs are showing safe and effective results in stroke patients. Further basic sciences of stem cell therapy on a neurovascular unit and neuroregeneration, and further clinical advancements on scaffold technology for supporting stem cells and stem cell tracking technology such as magnetic resonance imaging, single photon emission tomography or optical imaging with near-infrared could allow stem cell therapy to be applied in daily clinical applications in the near future.
Preserved Acetazolamide Reactivity in Lacunar Patients with Severe White-Matter Lesions: 15O-Labeled Gas and H2O Positron Emission Tomography Studies
Authors: Nezu Tomohisa , Yokota Chiaki , Uehara Toshiyuki , Yamauchi Miho , Fukushima Kazuhito , Toyoda Kazunori , Matsumoto Masayasu , Iida Hidehiro , Minematsu Kazuo
Published: January 2012

Limited evidence exists on the relationships between severity of white-matter lesions (WMLs) and cerebral hemodynamics in patients without major cerebral artery disease. To examine changes of cerebral blood flow (CBF), oxygen metabolism, and vascular reserve capacity associated with severity of WML in patients with lacunar stroke, we used a positron emission tomography (PET). Eighteen lacunar patients were divided into two groups according to the severity of WMLs, assessed by Fazekas classification; grades 0 to 1 as mild WML group and grades 2 to 3 as severe WML group. Rapid dual autoradiography was performed with 15O-labeled gas-PET followed by 15O-labeled water-PET with acetazolamide (ACZ) challenge. Compared with the mild WML group, the severe WML group showed lower CBF (20.6 ± 4.4 versus 29.9 ± 8.2 mL/100 g per minute, P = 0.008), higher oxygen extraction fraction (OEF) (55.2 ± 7.4 versus 46.7 ± 5.3%, P = 0.013), and lower cerebral metabolic rate of oxygen (CMRO2) (1.95 ± 0.41 versus 2.44 ± 0.42 mL/100 g per minute, P = 0.025) in the centrum semiovale. There were no significant differences in the ACZ reactivity between the two groups (48.6 ± 22.6% versus 42.5 ± 17.2%, P = 0.524). Lacunar patients with severe WMLs exhibited reduced CBF and CMRO2, and increased OEF in the centrum semiovale. The ACZ reactivity was preserved in both patients with severe and mild WMLs in each site of the brain.
Characterizing Brain Oxygen Metabolism in Patients with Multiple Sclerosis with T2-Relaxation-Under-Spin-Tagging MRI
Authors: Ge Yulin , Zhang Zhongwei , Lu Hanzhang , Tang Lin , Jaggi Hina , Herbert Joseph , Babb James S , Rusinek Henry , Grossman Robert I
Published: January 2012

In this study, venous oxygen saturation and oxygen metabolic changes in multiple sclerosis (MS) patients were assessed using a recently developed T2-relaxation-under-spin-tagging (TRUST) magnetic resonance imaging (MRI), which measures the superior sagittal venous sinus blood oxygenation ( Yv) and cerebral metabolic rate of oxygen ( CMRO 2), an index of global oxygen consumption. Thirty patients with relapsing-remitting MS and 30 age-matched healthy controls were studied using TRUST at 3 T MR. The mean expanded disability status scale (EDSS) of the patients was 2.3 (range, 0 to 5.5). We found significantly increased Yv ( P<0.0001) and decreased CMRO 2 ( P=0.003) in MS patients (mean±s.d.: 65.9%±5.1% and 138.8±35.4 μmol per 100 g per minute) as compared with healthy control subjects (60.2%±4.0% and 180.2±24.8 μmol per 100 g per minute, respectively), implying decrease of oxygen consumption in MS. There was a significant positive correlation between Yv and EDSS and between Yv and lesion load in MS patients ( n=30); on the contrary, there was a significant negative correlation between CMRO 2 and EDSS and between CMRO 2 and lesion load ( n=12). There was no correlation between Yv and brain atrophy measures. This study showed preliminary evidence of the potential utility of TRUST in global oxygen metabolism. Our results of significant underutilization of oxygen in MS raise important questions regarding mitochondrial respiratory dysfunction and neurodegeneration of the disease.
Neurological Diseases in Relation to the Blood–Brain Barrier
Authors: Rosenberg Gary A
Published: January 2012

Disruption of the blood–brain barrier (BBB) has an important part in cellular damage in neurological diseases, including acute and chronic cerebral ischemia, brain trauma, multiple sclerosis, brain tumors, and brain infections. The neurovascular unit (NVU) forms the interface between the blood and brain tissues. During an injury, the cascade of molecular events ends in the final common pathway for BBB disruption by free radicals and proteases, which attack membranes and degrade the tight junction proteins in endothelial cells. Free radicals of oxygen and nitrogen and the proteases, matrix metalloproteinases and cyclooxgyenases, are important in the early and delayed BBB disruption as the neuroinflammatory response progresses. Opening of the BBB occurs in neurodegenerative diseases and contributes to the cognitive changes. In addition to the importance of the NVU in acute injury, angiogenesis contributes to the recovery process. The challenges to treatment of the brain diseases involve not only facilitating drug entry into the brain, but also understanding the timing of the molecular cascades to block the early NVU injury without interfering with recovery. This review will describe the molecular and cellular events associated with NVU disruption and potential strategies directed toward restoring its integrity.
SED-ML: Nested Simulation Proposal
Authors: Bergmann Frank
Published: January 2012

This document describes a second version of the proposal for nested simulation experiments for SED-ML (http://sed-ml.org). The proposal has been updated to include the feedback received in the meantime and has been enhanced by examples. A full implementation is available with libSedML (http://libsedml.sf.net) and the SED-ML Web Tools (http://sysbioapps.dyndns.org/SED-ML_Web_Tools/)
Changes in Baroreflex Control of Renal Sympathetic Nerve Activity in High‐Fat‐Fed Rats as a Predictor of Hypertension
Authors: Fardin Núbia M. , Oyama Lila M. , Campos Ruy R.
Published: January 2012

There is evidence that obesity is associated with increased sympathetic activity and hypertension. However, the mechanisms responsible for these changes are not fully understood. Therefore, the aim of the present study was to evaluate the cardiovascular function and the baroreceptor reflex control of renal sympathetic nerve activity (rSNA) in rats exposed to a high‐fat diet over different periods (10 and 20 weeks) compared to control rats. Serum leptin levels were assessed for all time points. Male Wistar rats weighing 150–180 g were used. Four groups of rats were studied: control 10 weeks (Ct10), obese 10 weeks (Ob10), control 20 weeks (Ct20), and obese 20 weeks (Ob20). Blood pressure (BP) and rSNA were recorded in urethane‐anesthetized rats (1.4 g/kg, intravenous). The sensitivity of rSNA responses to baroreceptor reflex was assessed by changes in BP induced by increasing doses of phenylephrine or sodium nitroprusside. Significant and progressive increases in serum leptin levels were found in the obese rats, but not in the control rats. No changes in basal BP or rSNA were found in the Ob10 and Ob20 groups; however, a significant impairment in the baroreceptor sensitivity was observed in the Ob20 group for phenylephrine (slope Ob20: −0.78 ± 0.12 vs. Ct20: −1.00 ± 0.08 potential per second (pps)/mm Hg, P < 0.05) and sodium nitroprusside (slope Ob20: −0.82 ± 0.09 vs. 1.13 ± 0.13 pps/mm Hg, P < 0.05). The results suggest that the baroreceptor dysfunction that controls the rSNA is an initial change in the obesity induced in high‐fat‐fed rats, which might be a predictor of sympathoexcitation and hypertension associated to obesity.
Higher Prevalence of Obesity Among Children With Asthma
Authors: Black Mary Helen , Smith Ning , Porter Amy H. , Jacobsen Steven J. , Koebnick Corinna
Published: January 2012

The aim of this study is to investigate the association between childhood obesity and asthma, and whether this relationship varies by race/ethnicity. For this population‐based, cross‐sectional study, measured weight and height, and asthma diagnoses were extracted from electronic medical records of 681,122 patients aged 6–19 years who were enrolled in an integrated health plan 2007–2009. Weight class was assigned based on BMI‐for‐age. Overall, 18.4% of youth had a history of asthma and 10.9% had current asthma. Adjusted odds of current asthma for overweight, moderately obese, and extremely obese youth relative to those of normal weight were 1.22 (95% confidence interval (CI): 1.20, 1.24), 1.37 (95% CI: 1.34, 1.40), and 1.68 (95% CI: 1.64, 1.73), respectively (P trend < 0.001). Black youth are nearly twice as likely (adjusted odds ratio (OR) = 1.93, 95% CI: 1.89, 1.99), and Hispanic youth are 25% less likely (adjusted OR = 0.75, 95% CI: 0.74, 0.77), to have current asthma than to non‐Hispanic white youth. However, the relationship between BMI and asthma was strongest in Hispanic and weakest in black youth. Among youth with asthma, increasing body mass was associated with more frequent ambulatory and emergency department visits, as well as increased inhaled and oral corticosteroid use. In conclusion, overweight, moderate, and extreme obesity are associated with higher odds of asthma in children and adolescents, although the association varies widely with race/ethnicity. Increasing BMI among youth with asthma is associated with higher consumption of corticosteroids and emergency department visits.
Spatial resolution of the JET Thomson scattering system
Authors: Frassinetti L. , Beurskens M. N. A. , Scannell R. , Osborne T. H. , Flanagan J. , Kempenaars M. , Maslov M. , Pasqualotto R. , Walsh M. ,   JET-EFDA Contributors
Published: January 2012

The instrument function of the high resolution Thomson scattering (HRTS) diagnostic in the Joint European Torus (JET) has been calculated for use in improved pedestal profile analysis. The full width at half maximum (FWHM) of the spatial instrument response is (22 ± 1) mm for the original HRTS system configuration and depends on the particular magnetic topology of the JET plasmas. An improvement to the optical design of the laser input system is presented. The spatial smearing across magnetic flux surfaces is reduced in this design. The new input system has been implemented (from JPN 78742, July 2009) and the HRTS instrument function corresponding to the new configuration has been improved to approximately FWHM = (9.8 ± 0.8) mm. The reconstructed instrument kernels are used in combination with an ad hoc forward deconvolution procedure for pedestal analysis. This procedure produces good results for both the old and new setups, but the reliability of the deconvolved profiles is greatly reduced when the pedestal width is of the same order as, or less than the FWHM of the instrument kernel.
Applying for Home Mortgages in Immigrant Communities: The Case of Asian Applicants in Los Angeles
Authors: Zonta Michela M
Published: January 2012

In this paper it is argued that the spatial segmentation of financial services in urban areas, generated by a combination of financial market characteristics, transnational movements of people and capital, cultural practices, ethnic resources, and social networks may produce, at the early stages of the home mortgage application process, a sorting of Asian borrowers into mortgage channels that may differ from those of other minority groups and may have, in the long run, a different impact on the exposure and vulnerability of borrowers to adverse lending practices and products. The study employs multinomial logistic regression and GIS analysis of annual Home Mortgage Disclosure Data and explores trends in home mortgage loan applications to different types of lenders by Asian, white, and other minority prospective borrowers in the Los Angeles Metropolitan Area. Findings indicate that Asian applicants feature a greater propensity to apply for mortgage loans at very large mainstream banks and Asian-owned banks than at subprime lenders compared with other minority prospective borrowers. The larger presence of competing financial institutions in Asian immigrant markets may result in a greater access by Asian prospective borrowers to more options and, possibly, to higher quality and affordable mortgage products than other pools of minority applicants. At the same time, some of the social and cultural resources typically found in ethnic enclaves may affect how Asian applicants react to the outreach practices, sorting procedures, and products offered by different lenders.
Assembling Urbanism: Following Policies and ‘Studying Through’ the Sites and Situations of Policy Making
Authors: McCann Eugene , Ward Kevin
Published: January 2012

Recent years have seen a challenge to the territorial orthodoxy in urban studies. An interest in policy assemblage, mobility, and mutation has begun to open up ‘the what’ and ‘the where’ of urban policy making. Unfortunately—but perhaps not surprisingly—theoretical developments and empirical insights have run ahead of significant methodological considerations. This paper turns to some of the methodological consequences of studying the chains, circuits, networks, and webs in and through which policy and its associated discourses and ideologies are made mobile and mutable. It focuses on three rubrics under which methodological decisions can be made: ‘studying through’ (rather than studying up or down), techniques of following actors, policies, etc, and relational situations in which mobilization and assemblage happen. The paper concludes with a brief reflection on how academic research design and writing assemble cities and urban policy making in ways that parallel the assembling practices of policy actors.
Follow the Policy: A Distended Case Approach
Authors: Peck Jamie , Theodore Nik
Published: January 2012

The paper reflects on the methodological challenges involved in research on the movement and mutation of fast-moving policies, through globalizing networks and across translocal settings. Inspired by ‘follow the thing’ methods and by the global ethnography program, it outlines a distended case-study approach to the study of policy mobilities.
Governing Biosecurity in a Neoliberal World: Comparative Perspectives from Australia and the United Kingdom
Authors: Maye Damian , Dibden Jacqui , Higgins Vaughan , Potter Clive
Published: January 2012

International trade poses a serious and growing threat to biosecurity through the introduction of invasive pests and disease: these have adverse impacts on plant and animal health and public goods such as biodiversity, as well as food production capacity. While international governmental bodies such as the World Trade Organization (WTO) recognise such threats, and permit governments to protect human, animal, and plant life or health, such measures must not be applied in a way that is restrictive to trade. This raises a fundamental (but little-examined) tension between effective biosecurity governance and the neoliberal priorities of international trade. In this paper we examine how such tensions play out in the different political and geographical contexts of Australia and the United Kingdom. A comparative approach enables close scrutiny of how trade liberalisation and biosecurity are coconstituted as compatible objectives as well as the tensions and contradictions involved in making these domains a single governable problem. The comparative analysis draws attention to the policy challenges facing Australia and the UK in governing national biosecurity in a neoliberal world. These challenges reveal a complex geopolitics in the ways in which biosecurity is practised, institutionalised, and debated in each country, with implications for which pests and diseases are defined as threats and, therefore, which commodities are permitted to move across national borders. Despite efforts by the WTO to govern biosecurity as a technical matter of risk assessment and management, and to harmonise national practices, we contend that actual biosecurity practices continue to diverge between states depending on perceptions of risk and hazard, both to agricultural production and to rural environments as a whole, as well as unresolved tensions between internationalised neoliberalism and domestic concerns.