bluuebunny/crossref_metadata_2025 huggingface dataset:
The Thermal Conductivity of n‐Nonane and n‐Undecane at Pressures up to 500 MPa in the Temperature Range 35–90°C
Authors: Menashe J. , Wakeham W. A.
Published: July 2012

The paper presents new measurements of the thermal conductivity of two normal alkanes, n‐nonane, and n‐undecane, in the liquid phase. The measurements have been carried out within the temperature range 35 to 90°C and over the pressure range 50–500 MPa in a transient hot‐wire instrument. The experimental data, which have been corrected for the effects of radiation absorption, have an estimated uncertainty of ±0.7%. — A heuristic modification of the Enskog theory of transport processes in dense fluids is proposed, which leads to a simple means of representing the entire body of thermal conductivity data for each fluid with an accuracy commensurate with that of the measurements themselves. For each fluid the only temperature dependent parameter of the correlation scheme is a density independent core volume. It is therefore possible to predict the density dependence of the thermal conductivity of the fluid at any temperature from a single measurement at just one density.
The Chemisorption of Carbon Monoxide on a Co(10&1macr;0) Single Crystal Surface. Studied by LEED, UPS, EELS, AES and Work Function Measurements
Authors: Papp H.
Published: July 2012

The chemisorption of CO on Co(10&1macr;0) has been investigated by LEED, UPS, EELS, Auger and sp measurements. CO is molecularly adsorbed between 100 and 420 K. This can be deduced from UP spectra, EEL spectra and the reversibility of the sp and the LEED results. The initial isosteric heat of adsorption has a value of about 145 kJ/mol and drops to about 120 kJ/mol when a p(2 × 1) overlayer structure is completed. The final structure obtained at 300 K is a well ordered c(2 × 1) CO overlayer.
Blue‐green Chemiluminescence in the System C2H2/O/H. Formation of the Emitters CH(A2Δ), C2(d3Πg) and C2H*
Authors: Grebe J. , Homann K. H.
Published: July 2012

A kinetic study of the chemiluminescence of the emitters CH(A2Δ), C2(d3Πg) and C2H* in a mixture of acetylene, oxygen and hydrogen atoms has been performed using a low pressure discharge flow reactor at 2.66 mbar and 298 K under largely varying initial conditions. The absolute concentrations of the emitters could be quantitatively simulated and correlated to the simultaneous formation of higher hydrocarbons in this system when the following formation reactions of the excited species are assumed

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These reactions are in particular accord with the dependence of the chemiluminescence on the concentration of free hydrogen atoms.
Reversible Electrochemical Graphite Salt Formation from Aqueous Salt Electrolytes
Authors: Krohn H. , Beck F. , Junge H.
Published: July 2012

Cyclic electrochemical intercalation/deintercalation of anions from aqueous salt solutions in crystalline graphite electrodes has been investigated. The practical electrode was polypropylene bound natural graphite “CPP”. The main candidates for the salts were NaClO4, NaBF4, Na2SO4 and KF in the concentration range of 0.1 – 12 M. – Current efficiencies α with ClO−4 and BF−4 are lower as in aqueous acids due to side reactions, which increase with increasing dilution and temperature. No pH‐effect on α has been found between pH 1 – 12. Under favourable conditions (8 M NaClO4 at 20 °C or 4 M NaClO4 at 0 °C), α's as high as 80% have been observed. A pronounced formation effect is found upon galvanostatic cycling. In Na2SO4, α drops to zero at pH 3 due to the lack of HSO−4‐ions. No intercalation of F− ions is detected from aqueous KF. – Intercalation potential E1 shows Nernst behaviour with regard to anions in solution and intercalated anions. The slope of Nernst curve is 59 mV per decade as expected. E1 is much more positive than in aqueous acid of the same concentration due to the absence of solvate acid depolarization. The anions are desolvated, but not discharged upon intercalation. No indication of an in situ formation of solvate acid has been found. – For comparison, intercalation of anions from perchlorates in CH3OH, CH3COOH, and CH3CN has been investigated. – The potential application in an aqueous Zn/graphite accumulator is discussed. This battery has – with 4 M NaClO4 – an open circuit voltage of 2.58 V.
The Viscosity and Diffusion Coefficients of Binary Mixtures of Nitrous Oxide with Ar, N2, and CO2
Authors: Kestin J. , Ro S. T.
Published: July 2012

In our continuing search for extensions to the KRW law of corresponding states, we performed measurements of the low‐density viscosity of binary mixtures containing the mildly polar gas: N2O. This was combined with one monatomic gas (Ar), one diatomic gas (N2) and one somewhat more complex species (CO2). — Measurements of viscosity accurate to ±0.3% and direct calculations of binary diffusion coefficients confirm that the data fit into the general KRW scheme in that it is possible to discover optimum scaling factors ϱij and ϵij (i = j and i ± j) which correlate our data in terms of the universal collision integrals Ω11 and Ω22.
Attributable risk estimation for adjusted disability multistate models: Application to nosocomial infections
Authors: Coeurjolly Jean‐François , Nguile‐Makao Moliere , Timsit Jean‐François , Liquet Benoit
Published: July 2012

Attributable risk has become an important concept in clinical epidemiology. In this paper, we suggest to estimate the attributable risk of nosocomial infections using a multistate approach. Recently, a multistate model (called progressive disability model in the literature) has been developed in order to take into consideration both the time‐dependency of the risk factor (e.g., nosocomial infections) and the presence of competing risks (e.g., death and discharge) at each time point. However, this approach does not take into account the possible heterogeneity of the study population. In this paper, we investigate an extension of this model and suggest an adjusted disability multistate model including covariates in each transition. This new multistate model has led us to define the concepts of overall and profiled attributable risk. We use a classical semiparametric approach to estimate the model and the new attributable risk. A simulation study is investigated and we show, in particular, that neglecting the presence of covariates when estimating the model can lead to an important bias. The methodology developed in this paper is applied to data on ventilator‐associated pneumonia in 12 French intensive care units.
Strain stiffening in collagen I networks
Authors: Motte Stéphanie , Kaufman Laura J.
Published: July 2012

Biopolymer gels exhibit strain stiffening that is generally not seen in synthetic gels. Here, we investigate the strain‐stiffening behavior in collagen I gels that demonstrate elasticity derived from a variety of sources including crosslinking through telopeptides, bundling through low‐temperature gelation, and exogenous crosslinking with genipin. In all cases, it is found that these gels exhibit strain stiffening; in general, onset of strain stiffening occurs earlier, yield strain is lower, and degree of strain stiffening is smaller in higher concentration gels and in those displaying thick fibril bundles. Recovery after exposure to high strains is substantial and similar in all gels, suggesting that much of the stiffening comes from reversible network deformations. A key finding of this study is that collagen I gels of identical storage and loss moduli may display different nonlinear responses and different capacities to recover from high strain. © 2012 Wiley Periodicals, Inc.
Regulation of late endosomal/lysosomal maturation and trafficking by cortactin affects Golgi morphology
Authors: Kirkbride Kellye C. , Hong Nan Hyung , French Christi L. , Clark Emily S. , Jerome W. Gray , Weaver Alissa M.
Published: July 2012

Cortactin is a branched actin regulator and tumor‐overexpressed protein that promotes vesicular trafficking at a variety of cellular sites, including endosomes and the trans‐Golgi network. To better understand its role in secretory trafficking, we investigated its function in Golgi homeostasis. Here, we report that knockdown (KD) of cortactin leads to a dramatic change in Golgi morphology by light microscopy, dependent on binding the Arp2/3 actin‐nucleating complex. Surprisingly, there was little effect of cortactin‐KD on anterograde trafficking of the constitutive cargo vesicular stomatitis virus glycoprotein (VSVG), Golgi assembly from endoplasmic reticulum membranes upon Brefeldin A washout, or Golgi ultrastructure. Instead, electron microscopy studies revealed that cortactin‐KD cells contained a large number of immature‐appearing late endosomal/lysosomal (LE/Lys) hybrid organelles, similar to those found in lysosomal storage diseases. Consistent with a defect in LE/Lys trafficking, cortactin‐KD cells also exhibited accumulation of free cholesterol and retention of the retrograde Golgi cargo mannose‐6‐phosphate receptor in LE. Inhibition of LE maturation by treatment of control cells with Rab7 siRNA or chloroquine led to a compact Golgi morphology similar to that observed in cortactin‐KD cells. Furthermore, the Golgi morphology defects of cortactin‐KD cells could be rescued by removal of cholesterol‐containing lipids from the media, suggesting that buildup of cholesterol‐rich membranes in immature LE/Lys induced disturbances in retrograde trafficking. Taken together, these data reveal that LE/Lys maturation and trafficking are highly sensitive to cortactin‐regulated branched actin assembly and suggests that cytoskeletal‐induced Golgi morphology changes can be a consequence of altered trafficking at late endosomes. © 2012 Wiley Periodicals, Inc.
Dependence of the color appearance of some flowers on illumination
Authors: Yang Eun‐Mi , Kang Ho‐Min , Kim Chang‐Soon , Pak Chun Ho
Published: July 2012

Seven flower colors perceived by five color experts using visual color measurement under 2800 K warm white fluorescent lamps, 3500 K plant growth lamps, and 6500 K light‐emitting diodes (LEDs) were compared with those under 6500 K fluorescent lamps, which represented illuminants in florist shops. Fluorescent lamps (6500 K, 1000 lx) were found to be effective for displaying flower colors and were used as the standard condition. The colors of flowers generally shifted in the same direction as those of the illuminants in CIELAB space. The color differences were highest under the 3500 K fluorescent lamp at both 500 and 2000 lx. At 500 lx, the ΔE values under the 6500 K LED were higher than those under the 2800 K lamp. The C* and ΔE values revealed that the 2800 K lamp was unsatisfactory for purple‐blue and purple flowers and was more suitable for floral displays at lower illuminance. Under the 3500 K lamp, the highest color distortion occurred in cool‐colored flowers, but C* increased for purple‐blue and purple flowers. The 6500 K LED tended to decrease C* for warm‐colored flowers under both illuminances, but it was effective for displaying purple‐blue and purple flowers with increased C*. © 2012 Wiley Periodicals, Inc. Col Res Appl, 39, 28–36, 2014
Social context induces two unique patterns of c‐Fos expression in adolescent and adult rats
Authors: Varlinskaya Elena I. , Vogt Brent A. , Spear Linda P.
Published: July 2012

The study assessed possible age differences in brain activation patterns to low dose ethanol (.5 g/kg intraperitoneally) and the influence of social context on this activation. Early adolescent or young adult male Sprague–Dawley rats were placed either alone or with an unfamiliar partner of the same age and sex following saline or ethanol administration. c‐Fos protein immunoreactivity was used to index neuronal activation in 15 regions of interest. Ethanol had little effect on c‐Fos activation. In adolescents, social context activated an “autonomic” network including the basolateral and central amygdala, bed nucleus of the stria terminalis, lateral hypothalamus, and lateral septum. In contrast, when adult rats were alone, activation was evident in a “reward” network that included the substantia nigra, nucleus accumbens, anterior cingulate and orbitofrontal cortices, lateral parabrachial nucleus, and locus coeruleus.© 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 684–697, 2013.
Risk assessment and risk management at the Canadian Food Inspection Agency (CFIA): A perspective on the monitoring of foods for chemical residues
Authors: Bietlot Henri P. , Kolakowski Beata
Published: July 2012

The Canadian Food Inspection Agency (CFIA) uses ‘Ranked Risk Assessment’ (RRA) to prioritize chemical hazards for inclusion in monitoring programmes or method development projects based on their relative risk. The relative risk is calculated for a chemical by scoring toxicity and exposure in the ‘risk model scoring system’ of the Risk Priority Compound List (RPCL). The relative ranking and the risk management options are maintained and updated in the RPCL. The ranking may be refined by the data generated by the sampling and testing programs.

The two principal sampling and testing programmes are the National Chemical Residue Monitoring Program (NCRMP) and the Food Safety Action Plan (FSAP). The NCRMP sampling plans focus on the analysis of federally registered products (dairy, eggs, honey, meat and poultry, fresh and processed fruit and vegetable commodities, and maple syrup) for residues of veterinary drugs, pesticides, environmental contaminants, mycotoxins, and metals. The NCRMP is complemented by the Food Safety Action Plan (FSAP) targeted surveys. These surveys focus on emerging chemical hazards associated with specific foods or geographical regions for which applicable maximum residue limits (MRLs) are not set. The data from the NCRMP and FSAP also influence the risk management (follow‐up) options. Follow‐up actions vary according to the magnitude of the health risk, all with the objective of preventing any repeat occurrence to minimize consumer exposure to a product representing a potential risk to human health. © Her Majesty the Queen in Right of Canada 2012. Drug Testing and Analysis © 2012 John Wiley & Sons, Ltd.
The challenges of developing a generic extraction procedure to analyze multi‐class veterinary drug residues in milk and honey using ultra‐high pressure liquid chromatography quadrupole time‐of‐flight mass spectrometry
Authors: Wang Jian , Leung Daniel
Published: July 2012

This paper discusses the analytical challenges to develop a generic extraction procedure to analyze or screen multi‐class veterinary drugs in milk and honey using ultra‐high pressure liquid chromatography quadrupole time‐of‐flight mass spectrometry (UHPLC QqTOF MS). The veterinary drugs in this study included aminoglycosides, endectocides, fluoroquinolones, ionophores, β‐lactams or penicillins, macrolides, NSAIDs, phenicols, sulfonamides and tetracyclines. Veterinary drugs were extracted using a QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, which entailed the use of acetonitrile containing 1% acetic acid, sodium acetate, ethylenediaminetetra acetic acid disodium (EDTA) and magnesium sulfate, and no clean‐up was performed. Chromatographic separation was achieved on a reversed‐phase Acquity UPLC BEH C18, 100 × 2.1 mm, 1.7 µm column with 0.1% formic acid and 10 mM ammonium formate in water, and acetonitrile as mobile phases. Due to poor chromatographic retention, aminoglycosides were first dropped from the list, and because of poor extractability, β‐lactams and tetracyclines were also excluded from the method. The method was able to quantify 31 or screen up to 54 drugs (unbound) in honey, and to quantify 34 or screen up to 59 drugs in milk. UHPLC QqTOF data were acquired in TOF MS full‐scan mode that allowed both quantification and confirmation of veterinary drugs and identification of their degradation products in samples. The method could achieve detection limits as low as 1 µg/kg with analytical range from 1 to 100 µg/kg. The developed method was intended to be used for screening of as many analytes as possible in one single analysis, or unequivocal confirmation of positive findings and degradation product identification based on accurate mass measurement and isotopic patterns. © Her Majesty the Queen in Right of Canada 2012. Reproduced with the permission of the Minister of Agriculture.
Analytical difficulties facing today's regulatory laboratories: issues in method validation
Authors: MacNeil James D.
Published: July 2012

The challenges facing analytical laboratories today are not unlike those faced in the past, although both the degree of complexity and the rate of change have increased. Challenges such as development and maintenance of expertise, maintenance and up‐dating of equipment, and the introduction of new test methods have always been familiar themes for analytical laboratories, but international guidelines for laboratories involved in the import and export testing of food require management of such changes in a context which includes quality assurance, accreditation, and method validation considerations. Decisions as to when a change in a method requires re‐validation of the method or on the design of a validation scheme for a complex multi‐residue method require a well‐considered strategy, based on a current knowledge of international guidance documents and regulatory requirements, as well the laboratory's quality system requirements. Validation demonstrates that a method is ‘fit for purpose’, so the requirement for validation should be assessed in terms of the intended use of a method and, in the case of change or modification of a method, whether that change or modification may affect a previously validated performance characteristic. In general, method validation involves method scope, calibration‐related parameters, method precision, and recovery. Any method change which may affect method scope or any performance parameters will require re‐validation. Some typical situations involving change in methods are discussed and a decision process proposed for selection of appropriate validation measures. © 2012 John Wiley & Sons, Ltd.
Evaluation of a multi‐class, multi‐residue liquid chromatography – tandem mass spectrometry method for analysis of 120 veterinary drugs in bovine kidney
Authors: Schneider Marilyn J. , Lehotay Steven J. , Lightfield Alan R.
Published: July 2012

Traditionally, regulatory monitoring of veterinary drug residues in food animal tissues involves the use of several single‐class methods to cover a wide analytical scope. Multi‐class, multi‐residue methods (MMMs) of analysis tend to provide greater overall laboratory efficiency than the use of multiple methods, and liquid chromatography–tandem mass spectrometry (LC‐MS/MS) of targeted drug analytes usually provides exceptional performance even for complicated sample extracts. In this work, an LC‐MS/MS method was optimized and validated in a test of 120 drug analytes from 11 different classes in bovine kidney. The method used 10 ml of 4/1 acetonitrile/water for extraction of 2 g samples and cleanup with hexane partitioning. Quantitative and qualitative performance was assessed for the analytes at fortification levels of 10, 50, 100, and 200 ng/g. With the method, 66 drugs gave 70–120% recovery with ≤20% RSD at all levels over the course of 3 days. At the 200 ng/g level, 89 drugs met these same standards. Limits of detection were ≤10 ng/g for 109 of the analytes in the kidney matrix in validation experiments. Qualitatively, MS/MS identification criteria were set that ion ratios occur within ±10% (absolute value) from those of the analyte reference standards. At the 10 ng/g level, 57% of the drugs met the identification criteria, which improved to 84% at the 200 ng/g level. The method serves as an efficient and useful additional option among the current monitoring methods available. Published 2012. This article is a U.S. Government work and is in the public domain of the USA.
Development and validation of a streamlined method designed to detect residues of 62 veterinary drugs in bovine kidney using ultra‐high performance liquid chromatography – tandem mass spectrometry
Authors: Lehotay Steven J. , Lightfield Alan R. , Geis‐Asteggiante Lucía , Schneider Marilyn J. , Dutko Terry , Ng Chilton , Bluhm Louis , Mastovska Katerina
Published: July 2012

In the USA, the US Department of Agriculture's Food Safety and Inspection Service (FSIS) conducts the National Residue Program designed to monitor veterinary drug and other chemical residues in beef and other slaughtered food animals. Currently, FSIS uses a 7‐plate bioassay in the laboratory to screen for antimicrobial drugs in bovine kidneys from those animals tested positive by inspectors in the slaughter establishments. The microbial inhibition bioassay has several limitations in terms of monitoring scope, sensitivity, selectivity, and analysis time. Ultra‐high performance liquid chromatography – tandem mass spectrometry (UHPLC‐MS/MS) has many advantages over the bioassay for this application, and this study was designed to develop, evaluate, and validate a fast UHPLC‐MS/MS method for antibiotics and other high‐priority veterinary drugs in bovine kidney. Five existing multi‐class, multi‐residue methods from the literature were tested and compared, and each performed similarly. Experiments with incurred samples demonstrated that a 5‐min shake of 2 g homogenized kidney with 10 ml of 4/1 (v/v) acetonitrile/water followed by simultaneous clean‐up of the initial extract with 0.5 g C18 and 10 ml hexane gave a fast, simple, and effective sample preparation method for the <10 min UHPLC‐MS/MS analysis. An extensive 5‐day validation process demonstrated that the final method could be used to acceptably screen for 54 of the 62 drugs tested, and 50 of those met qualitative MS identification criteria. Quantification was not needed in the application, but the method gave ≥70% recoveries and ≤25% reproducibilities for 30 of the drugs. Published 2012. This article is a U.S. Government work and is in the public domain of the USA.
CD163 favors Mycobacterium leprae survival and persistence by promoting anti‐inflammatory pathways in lepromatous macrophages
Authors: Moura Danielle F. , de Mattos Katherine A. , Amadeu Thaís P. , Andrade Priscila R. , Sales Jorgenilce S. , Schmitz Verônica , Nery José Augusto C. , Pinheiro Roberta O. , Sarno Euzenir N.
Published: July 2012

Lepromatous macrophages possess a regulatory phenotype that contributes to the immunosuppression observed in leprosy. CD163, a scavenger receptor that recognizes hemoglobin–haptoglobin complexes, is expressed at higher levels in lepromatous cells, although its functional role in leprosy is not yet established. We herein demonstrate that human lepromatous lesions are microenvironments rich in IDO+CD163+. Cells isolated from these lesions were CD68+IDO+CD163+ while higher levels of sCD163 in lepromatous sera positively correlated with IL‐10 levels and IDO activity. Different Myco‐bacterium leprae (ML) concentrations in healthy monocytes likewise revealed a positive correlation between increased concentrations of the mycobacteria and IDO, CD209, and CD163 expression. The regulatory phenotype in ML‐stimulated monocytes was accompanied by increased TNF, IL‐10, and TGF‐β levels whereas IL‐10 blockade reduced ML‐induced CD163 expression. The CD163 blockade reduced ML uptake in human monocytes. ML uptake was higher in HEK293 cells transfected with the cDNA for CD163 than in untransfected cells. Simultaneously, increased CD163 expression in lepromatous cells seemed to be dependent on ML uptake, and contributed to augmented iron storage in lepromatous macrophages. Altogether, these results suggest that ML‐induced CD163 expression modulates the host cell phenotype to create a favorable environment for myco‐bacterial entry and survival.
Fabrication of Flexible α‐Alumina Fibers Composed of Nanosheets
Authors: Zhang Pingping , Chen Dairong , Jiao Xiuling
Published: July 2012

Flexible α‐alumina nanofibers were fabricated by the sol–gel method combined with an electrospinning process. The sol was prepared with aluminum isopropoxide and aluminum nitrate as the precursors, nitric acid as the catalyst, and ethanol aqueous solution as the solvent. Small amounts of anhydrous magnesium sulfate as additive acted to stabilize the γ‐Al2O3 structure and retard its conversion to α‐Al2O3 firstly, and subsequently MgAl2O4 was formed at the grain boundaries to inhibit grain growth. Polyvinylpyrrolidone (PVP) was applied to tune sol viscosity. The fibers with diameters of 300–400 nm are composed of α‐Al2O3 nanosheets with thickness in the range of 20–50 nm and stack along [0001] at the axial direction. The fibers exhibited good flexibility and thermal stability.
Synthesis of 4‐Hydroxy‐5‐methyl‐ and 4‐Hydroxy‐6‐methylcyclohexenones by PdII‐Catalyzed Oxidation and Lipase‐Catalyzed Hydrolysis
Authors: Meister Anne C. , Nieger Martin , Bräse Stefan
Published: July 2012

A short route for the syntheses of methyl‐substituted hydroxycyclohexenones, which are building blocks for various natural products, is presented. Both oxygen atoms were introduced as acetates by a palladium(II)‐catalyzed 1,4‐addition to a 1,3‐diene. The distinction between the two acetoxy groups was achieved by regioselective monohydrolysis with lipase from Candida rugosa, which gave 1‐acetoxy‐4‐hydroxy‐5‐methylcyclohexene and its 6‐methyl regioisomer as a separable mixture. The target compounds 4‐hydroxy‐5‐methylcyclohex‐2‐enone and 4‐hydroxy‐6‐methylcyclohex‐2‐enone could then be obtained as diastereomeric mixtures in good overall yields and with moderate enantiomeric excesses (31–67 %).
Microfluidic transport in microdevices for rare cell capture
Authors: Smith James P. , Barbati Alexander C. , Santana Steven M. , Gleghorn Jason P. , Kirby Brian J.
Published: July 2012

The isolation and capture of rare cells is a problem uniquely suited to microfluidic devices, in which geometries on the cellular length scale can be engineered and a wide range of chemical functionalizations can be implemented. The performance of such devices is primarily affected by the chemical interaction between the cell and the capture surface and the mechanics of cell‐surface collision and adhesion. As rare cell‐capture technology has been summarized elsewhere (E. D. Pratt et al.,Chem. Eng. Sci. 2011,66, 1508–1522), this article focuses on the fundamental adhesion and transport mechanisms in rare cell‐capture microdevices, and explores modern device design strategies in a transport context. The biorheology and engineering parameters of cell adhesion are defined; adhesion models and reaction kinetics briefly reviewed. Transport at the microscale, including diffusion and steric interactions that result in cell motion across streamlines, is discussed. The review concludes by discussing design strategies with a focus on leveraging the underlying transport phenomena to maximize device performance.
Plankton Succession in the Temporary Lake Koronia after Intermittent Dry‐Out
Authors: Michaloudi Evangelia , Moustaka‐Gouni Maria , Pantelidakis Kimon , Katsiapi Matina , Genitsaris Savvas
Published: July 2012

This study examines the plankton succession in a polluted temporary lake after intermittent dry‐out. The initial stage after flooding was heterotrophic (zooplankton/phytoplankton carbon biomass ratio > 1). Phytoplankton species richness increased exponentially within a few months after inundation. The chlorophyte Koliella cf. longiseta was the pioneer colonist which was replaced by Oocystis sp. reaching 300 340 ind mL–1. The initial conditions favored rotifer and cladoceran colonists, not previously recorded, to successfully establish populations. The species that finally became dominant hatched from the lake's sedimentary egg bank with Daphnia magna being prominent. Nevertheless, the zooplankton community was unable to control the high biomass of chlorophytes (zooplankton/phytoplankton carbon biomass ratio < 0.4). Plankton succession in this temporary lake was mostly determined by the past phytoplankton – zooplankton species pool rather than by the established new colonists. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study on in vitro release and cell response to alendronate sodium‐loaded ultrahigh molecular weight polyethylene loaded with alendronate sodium wear particles to treat the particles‐induced osteolysis
Authors: Qu Shuxin , Bai Yinlong , Liu Xiaomin , Fu Rong , Duan Ke , Weng Jie
Published: July 2012

The aim of this study is to investigate in vitro release and cell response to wear particles of ultrahigh molecular weight polyethylene loaded with alendronate sodium (UHMWPE‐ALN), a potent bone resorption inhibitor. Wear particles of UHMWPE‐ALN with different ALN contents (0.5 wt % or 1.0 wt %) and size ranges (<45 μm or 45–75 μm) were cocultured with macrophages (RAW264.7) and osteoblasts (MC3T3‐E1), respectively. The in vitro ALN release was divided into three stages: an initial burst release, subsequent rapid release, and final slow release. The particle size and ALN content of UHMWPE‐ALN wear particles affected the in vitro release mainly during initial burst and rapid release. Compared with the control cells, UHMWPE‐ALN wear particles stimulated a significant elevation of tumor necrosis factor‐alpha (TNF‐α) release from macrophages but had no obvious effect on interleukin‐6 release. However, this stimulation of TNF‐α release could be reduced by ALN released from UHMWPE‐ALN wear particles. The wear particle size had stronger effect of on the macrophages compared with the ALN concentration. After coculture with UHMWPE‐ALN wear particles, osteoblast proliferation and alkaline phosphatase activities increased moderately with the increase in particle sizes and ALN concentrations. These results suggest that incorporation of ALN in UHMWPE‐ALN may be an effective approach to prevent or reduce particles‐induced osteolysis. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
HIV‐1 protein induced modulation of primary human osteoblast differentiation and function via a Wnt/β‐catenin‐dependent mechanism
Authors: Butler Joseph S. , Dunning Eilis C. , Murray David W. , Doran Peter P. , O'Byrne John M.
Published: July 2012

HIV infection is associated with metabolic bone disease resulting in bone demineralization and reduced bone mass. The molecular mechanisms driving this disease process have yet to be elucidated. Wnt/β‐catenin signaling plays a key role in bone development and remodeling. We attempted to determine the effects of the HIV‐1 protein, gp120, on Wnt/β‐catenin signaling at an intracellular and transcriptional level in primary human osteoblasts (HOBs). This work, inclusive of experimental controls, was part of a greater project assessing the effects of a variety of different agents on Wnt/β‐catenin signaling (BMC Musculoskelet Disord 2010;11:210).We examined the phenotypic effects of silencing and overexpressing the Wnt antagonist, Dickkopf‐1 (Dkk1) in HOBs treated with gp120. HOBs exposed to gp120 displayed a significant reduction in alkaline phosphatase activity (ALP) activity and cell proliferation and increased cellular apoptosis over a 48 h time course. Immunocytochemistry demonstrated a significant reduction in intracytosolic and intranuclear β‐catenin in response to HIV‐1 protein exposure. These changes were associated with a reduction of TCF/LEF‐mediated transcription, the transcriptional outcome of canonical Wnt β‐catenin signaling. Silencing Dkk1 expression in HOBs exposed to gp120 resulted in increased ALP activity and cell proliferation, and decreased cellular apoptosis relative to scrambled control. Dkk1 overexpression exacerbated the inhibitory effect of gp120 on HOB function, with decreases in ALP activity and cell proliferation and increased cellular apoptosis relative to vector control. Wnt/β‐catenin signaling plays a key regulatory role in HIV‐associated bone loss, with Dkk1, aputative central mediator in this degenerative process. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 218–226, 2013
Long‐term outcomes following foscan®‐PDT of basal cell carcinomas
Authors: Betz Christian S. , Rauschning Winrich , Stranadko Evgueni Ph. , Riabov Mikhail V. , Volgin Valery N. , Albrecht Volker , Nifantiev Nikolay E. , Hopper Colin
Published: July 2012

Background and Objective

In a previous publication we showed that mTHPC‐PDT (Foscan®‐PDT) is an effective treatment of basal cell carcinomas (BCCs) in “difficult to treat” locations and presented optimized treatment parameters to reduce costs and side effects. Now we present long‐term results of the same study population.

Study Design/Materials and Methods

Following PDT of a total of 460 BCCs in 117 subjects, the patients/lesions were followed‐up for a mean duration of 42 (range: 2–72) months. Two patients dropped out of follow‐up; 13 patients died of unrelated causes. Recurrences were treated either by repeated PDT or other established methods.

Results

The sustained clearance rate was 93.7% and the overall treatment success rate was 90.7%. Kaplan–Meier analysis revealed an estimated recurrence free fraction of patients at 5 years of 95.1%, 92.4%, 85.1%, and 74.0% for the four different photosensitizer dose groups (0.06–0.15, 0.05, 0.04, and 0.03 mg/kg). High‐risk lesions (recurrences, thickness >3 mm) recurred more often than low‐risk ones, and recurrences mostly (>50%) occurred during the first year of follow‐up.

Conclusion

Long‐term outcomes of high‐dose (0.06–0.15 mg/kg) and reduced‐dose (0.05 mg/kg) Foscan®‐PDT in “difficult to treat” BCCs compare favorably with other methods, even in high‐risk lesions (recurrent and/or thick lesions). A recommended combination of treatment parameters for low‐dose therapy seems to be: 0.05 mg/kg Foscan®, 24 hours drug–light interval (DLI), fluence ≥40 J/cm2. Prospective randomized studies are needed to look into low‐dose mTHPC‐PDT of BCCs in more detail and to directly compare it with other treatments. Lasers Surg. Med. 44: 533–540, 2012. © Wiley Periodicals, Inc.
Upregulation of the long non‐coding rna hotair promotes esophageal squamous cell carcinoma metastasis and poor prognosis
Authors: Chen Fang‐Jun , Sun Ming , Li Su‐Qing , Wu Qing‐Quan , Ji Lv , Liu Zhi‐Li , Zhou Guo‐Zhi , Cao Gang , Jin Lei , Xie Hai‐Wei , Wang Chun‐Mei , Lv Jin , De Wei , Wu Ming , Cao Xiu‐Feng
Published: July 2012

Recent studies of the individual functionalities of long non‐coding RNAs (lncRNAs) in the development and progression of cancer have suggested that HOX transcript antisense RNA (HOTAIR) is capable of reprogramming chromatin organization and promoting cancer cell metastasis. In order to ascertain the expression pattern of the lncRNA HOTAIR and assess its biological role in the development and progression of esophageal squamous cell carcinoma (ESCC), HOTAIR expression in ESCC tissues and adjacent noncancerous tissues were collected from 78 patients and measured by real‐time reverse transcription‐polymerase chain reaction (RT‐PCR). HOTAIR correlation with clinicopathological features and prognosis was also analyzed. Suppression of HOTAIR using siRNA treatment was performed in order to explore its role in tumor progression. Notably elevated HOTAIR expression levels were observed in cancerous tissues compared to adjacent noncancerous tissues (96%, P < 0.01), showing a high correlation with cancer metastasis (P < 0.01), elevated TNM (2009) stage classification (P < 0.01), and lowered overall survival rates (P = 0.003). Multivariate analysis revealed that HOTAIR expression (P = 0.003) is also an independent prognostic factor for comparison of TNM stage (P = 0.024) and lymph node metastasis (P = 0.010). Furthermore, in vitro assays of the ESCC cell line KYSE30 demonstrated that knockdown of HOTAIR reduced cell invasiveness and migration while increasing the response of cells to apoptosis. Thus, HOTAIR is a novel molecule involved in both ESCC progression and prognosis. Full elucidation of HOTAIR functionality relevant to ESCC may open avenues for the use of lncRNAs in identification of novel drug targets and therapies for ESCC and other prevalent cancers. © 2012 Wiley Periodicals, Inc.
The convolution and multiplication of one‐dimensional associated homogeneous distributions
Authors: Franssens Ghislain R.
Published: July 2012

The set of associated homogeneous distributions (AHDs) with support in R is an important subset of the tempered distributions because it contains the majority of the (one‐dimensional) distributions typically encountered in physics applications (including the δ distribution). In a previous work of the author, a convolution and multiplication product for AHDs on R was defined and fully investigated. The aim of this paper is to give an easy introduction to these new distributional products.

The constructed algebras are internal to Schwartz’ theory of distributions and, when one restricts to AHDs, provide a simple alternative for any of the larger generalized function algebras, currently used in non‐linear models. Our approach belongs to the same class as certain methods of renormalization, used in quantum field theory, and are known in the distributional literature as multi‐valued methods. Products of AHDs on R, based on this definition, are generally multi‐valued only at critical degrees of homogeneity. Unlike other definitions proposed in this class, the multi‐valuedness of our products is canonical in the sense that it involves at most one arbitrary constant. A selection of results of (one‐dimensional) distributional convolution and multiplication products are given, with some of them justifying certain distributional products used in quantum field theory. Copyright © 2012 John Wiley & Sons, Ltd.
A 64‐channel 3T array coil for accelerated brain MRI
Authors: Keil Boris , Blau James N. , Biber Stephan , Hoecht Philipp , Tountcheva Veneta , Setsompop Kawin , Triantafyllou Christina , Wald Lawrence L.
Published: July 2012

A 64‐channel brain array coil was developed and compared to a 32‐channel array constructed with the same coil former geometry to precisely isolate the benefit of the 2‐fold increase in array coil elements. The constructed coils were developed for a standard clinical 3T MRI scanner and used a contoured head‐shaped curved former around the occipital pole and tapered in at the neck to both improve sensitivity and patient comfort. Additionally, the design is a compact, split‐former design intended for robust daily use. Signal‐to‐noise ratio and noise amplification (G‐factor) for parallel imaging were quantitatively evaluated in human imaging and compared to a size and shape‐matched 32‐channel array coil. For unaccelerated imaging, the 64‐channel array provided similar signal‐to‐noise ratio in the brain center to the 32‐channel array and 1.3‐fold more signal‐to‐noise ratio in the brain cortex. Reduced noise amplification during highly parallel imaging of the 64‐channel array provided the ability to accelerate at approximately one unit higher at a given noise amplification compared to the sized‐matched 32‐channel array. For example, with a 4‐fold acceleration rate, the central brain and cortical signal‐to‐noise ratio of the 64‐channel array was 1.2‐ and 1.4‐fold higher, respectively, compared to the 32‐channel array. The characteristics of the coil are demonstrated in accelerated brain imaging. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Hyperpolarized singlet NMR on a small animal imaging system
Authors: Laustsen Christoffer , Pileio Giuseppe , Tayler Michael C. D. , Brown Lynda J. , Brown Richard C. D. , Levitt Malcolm H. , Ardenkjaer‐Larsen Jan H.
Published: July 2012

Nuclear spin hyperpolarization makes a significant advance toward overcoming the sensitivity limitations of in vivo magnetic resonance imaging, particularly in the case of low‐gamma nuclei. The sensitivity may be improved further by storing the hyperpolarization in slowly relaxing singlet populations of spin‐1/2 pairs. Here, we report hyperpolarized 13C spin order transferred into and retrieved from singlet spin order using a small animal magnetic resonance imaging scanner. For spins in sites with very similar chemical shifts, singlet spin order is sustained in high magnetic field without requiring strong radiofrequency irradiation. The demonstration of robust singlet‐to‐magnetization conversion, and vice versa, on a small animal scanner, is promising for future in vivo and clinical deployments. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Sensitivity analysis applied to finite element method model for coupled multiphase system
Authors: Ngaradoumbe Nanhorngué R. , Pesavento F. , Schrefler B.A.
Published: July 2012

Today multiphysics problems applied to various fields of engineering have become increasingly important. Among these, in the areas of civil, environmental and nuclear engineering, the problems related to the behaviour of porous media under extreme conditions in terms of temperature and/or pressure are particularly relevant. The mathematical models used to solve these problems have an increasing complexity leading to increase of computing times. This problem can be solved by using more effective numerical algorithms, or by trying to reduce the complexity of these models. This can be achieved by using a sensitivity analysis to determine the influence of model parameters on the solution. In this paper, the sensitivity analysis of a mathematical/numerical model for the analysis of concrete as multiphase porous medium exposed to high temperatures is presented. This may lead to a reduction of the number of the model parameters, indicating what parameters should be determined in an accurate way and what can be neglected or found directly from the literature. Moreover, the identification parameters influence may allow to proceeding to a simplification of the mathematical model (i.e. model reduction). The technique adopted in this paper to performing the sensitivity analysis is based on the automatic differentiation (AD), which allowed to develop an efficient tool for the computation of the sensitivity coefficients. The results of the application of AD technique have been compared with the results of the more standard finite difference method, showing the superiority of the AD in terms of numerical accuracy and execution times. From the results of the sensitivity analysis, it follows that a drastic simplification of the model for thermo‐chemo‐hygro‐mechanical behaviour of concrete at high temperature, is not possible. Therefore, it is necessary to use different model reduction techniques in order to obtain a simplified version of the model that can be used at industrial level. Copyright © 2012 John Wiley & Sons, Ltd.
Reduced order mesh optimisation using proper orthogonal decomposition and a modified cuckoo search
Authors: Walton S. , Hassan O. , Morgan K.
Published: July 2012

A new mesh optimisation scheme, reduced order mesh optimisation, is introduced. The technique uses proper orthogonal decomposition to reduce the number of dimensions in a mesh optimisation problem. This reduction in dimensionality allows the expression of the optimisation problem globally rather than the more traditional local mesh optimisation or smoothing algorithms. To perform the optimisation, the recently developed gradient‐free technique modified cuckoo search is applied. The effectiveness of the algorithm is shown by considering the problem of optimising meshes for use in co‐volume techniques. Co‐volume techniques require the existence of two mutually orthogonal meshes; this is achieved by utilising the Delaunay–Voronoi dual. A combination of considering the problem globally and the use of a gradient‐free technique results in a scheme that significantly outperforms previous methods in solving this particular problem. Although the examples presented in this paper are specific to optimising dual meshes, the technique is general and can be simply modified to any mesh optimisation problem. Copyright © 2012 John Wiley & Sons, Ltd.
Aberrant right subclavian artery (ARSA) in unselected population at first and second trimester ultrasonography
Authors: Rembouskos G. , Passamonti U. , De Robertis V. , Tempesta A. , Campobasso G. , Volpe G. , Gentile M. , Volpe P.
Published: July 2012

Objectives

To evaluate the feasibility of examining aberrant right subclavian artery (ARSA) at first and second trimester gestation, its prevalence and associations in an unselected population.

Methods

Right subclavian artery (RSA) was prospectively evaluated in 6617 routine patients. When ARSA was detected, fetal echocardiography was offered and fetal karyotyping was discussed. If invasive testing was performed with normal karyotype, fluorescence in situ hybridization for 22q11.2 microdeletion and additionally, in case of nuchal translucency (NT) measurement above the 99th centile, oligo array‐based comparative genomic hybridization, were offered. In all aneuploidies, NT and first trimester additional ultrasonographic (US) markers assessment (nasal bone, tricuspid valve, ductus venosus) were recorded.

Results

RSA assessment was feasible in 85.3% and 98% of first and second trimester examinations, respectively (overall feasibility 94%). There were detected 89 ARSA (1.42% of the feasible cases), of which 66 in the first trimester. More than 20% were associated to other abnormalities: 10 aneuploidies; 2 microdeletions (15q11.2 and 22q11.2); in the euploid fetuses, 8 associated abnormalities were observed, 4 of which were cardiac defects. In the case of 22q11.2 microdeletion, ARSA was associated only with increased NT.

Conclusion

Prenatal routine US assessment of the RSA is feasible by highly experienced operators in first trimester screening. There is an important association of ARSA detected in unselected population with fetal abnormalities, including aneuploidies, cardiac defects and genetic anomalies. In trisomy 21 fetuses, ARSA can be the only first trimester US marker or, when associated to increased NT, it can represent the only ‘additional’ marker. © 2012 John Wiley & Sons, Ltd.
Effects of polyvinyl chloride and aluminum trichloride on structure and property of polyaniline composite films by electron beam deposition
Authors: Liu Zhubo , Rogachev A.A. , Zhou Bing , Yarmolenko M.A. , Ragachev A.V. , Gorbachev D.L. , Jiang Xiaohong
Published: July 2012

Polyaniline (PANI) composite films were prepared on silicon and quartz glass substrates by electron beam deposition (EBD), using polyvinyl chloride (PVC), aluminum trichloride (AlCl3), and mixture of PVC and AlCl3 as dopants. Molecular structure, morphology, optical, and electrical properties of PANI composite films were investigated by Fourier transform infrared spectroscopy, UV–vis spectroscopy, four‐probe method, and atomic force microscope. The results show that PANI film prepared by EBD has a similar molecular structure with initial powder. PVC is dehydrochlorinated under electron beam irradiation, but HCl fails to protonate the quinoid site of PANI during films deposition. AlCl3 doped in PANI films induces the decrease of surface resistance and the formation of a two‐layered morphological structure in composite film. In addition, AlCl3 enhances the decomposition of PVC and increases the surface resistance of (AlCl3, PVC)‐doped PANI composite film. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers