bluuebunny/crossref_metadata_2025 huggingface dataset:
Human dental follicle precursor cells of wisdom teeth: isolation and differentiation towards osteoblasts for implants with and without scaffolds
Authors: Haddouti E.‐M. , Skroch M. , Zippel N. , Müller C. , Birova B. , Pansky A. , Kleinfeld C. , Winter M. , Tobiasch E.
Published: October 2009

The human dental follicle is a developmental precursor for essential periodontal tissues such as periodontal ligament and root development. These cells can be expected to differentiate into several lineages, since they are derived from mesoderm. Especially the differentiation towards the osteogenic lineage could be interesting for tissue regeneration with or without growing on scaffold biomaterials in autologous transplantation for reconstruction of large bone defects and incorporation of teeth implants.

Here we demonstrate a fast and efficient method to isolate stem cells out of the dental follicle of wisdom teeth and their more determined lineage specific commitment into the osteogenic direction.

Typical markers confirmed the stem cell character of the isolated and differentiated cells and the successful differentiation has been verified in addition after lineage specific induction using corresponding stainings. In order to evaluate the quality of the cells microbiological investigations were performed and showed that all samples contained microbial species. Pre‐treatment of patients with antibiotics reduced the number of microorganisms to a minimum but did not suffice to eliminate all bacteria. The predominantly found species were gram‐positive cocci being either catalase‐positive and oxidase‐negative or catalase‐ and oxidase‐negative. Most microorganisms belonged to the families of Streptococcaceae and Staphylococcaceae. During cultivation of the stem cells, the contamination with microorganisms could be easily suppressed by usage of standard cell culture conditions with penicillin and streptomycin.
Gene expression changes in blood as a putative biomarker for Huntington's disease
Authors: Lovrecic Luca , Kastrin Andrej , Kobal Jan , Pirtosek Zvezdan , Krainc Dimitri , Peterlin Borut
Published: October 2009

Several studies demonstrated alterations of gene expression in blood in various neurological disorders including Huntington's disease (HD). Using microarray technology, a recent study identified a large number of significantly altered mRNAs in HD blood, from which a 12‐gene set was selected as classifier for discriminating controls and HD patients. The aim of our study was to validate expression changes of these 12 genes in an independent cohort of HD patients and evaluate their sensitivity and specificity. Four different subject groups were included—patients with HD, Parkinson's disease (PD), acute ischemic stroke (AS) and healthy controls. Although the previous results were successfully validated, gene expression changes in HD blood partly overlapped with those observed in blood from PD and AS patients. Predictive value of the selected biomarker set for HD group was 78%, with 82% sensitivity and 53% specificity. Further gene expression analyses in longitudinal studies are needed to validate and refine possible transcriptomic blood biomarkers in HD. © 2009 Movement Disorder Society
Nigrostriatal dysfunction in homozygous and heterozygous parkin gene carriers: An 18F‐dopa PET progression study
Authors: Pavese Nicola , Khan Naheed L. , Scherfler Christoph , Cohen Lisa , Brooks David J. , Wood Nicholas W. , Bhatia Kailash P. , Quinn Niall P. , Lees Andrew J. , Piccini Paola
Published: October 2009

Little is known about the rate of progression of striatal dysfunction in subjects with parkin‐linked parkinsonism. Being a heterozygous parkin gene carrier may confer susceptibility to Parkinson's disease (PD). In a previous 18F‐dopa PET study, we reported that 69% of carriers of a single parkin mutation showed subclinical loss of putamen dopaminergic function. Using serial 18F‐dopa PET, the present longitudinal study addresses rates of progression of nigrostriatal dysfunction in both compound heterozygous (parkin‐linked parkinsonism) and single heterozygous parkin gene carriers. Three symptomatic patients who were compound heterozygotes for parkin gene mutations and six asymptomatic heterozygous carriers were clinically assessed and had 18F‐dopa PET at baseline and again after 5 years. The patients with symptomatic parkin showed a mean 0.5% annual reduction in putamen 18F‐dopa uptake over 5 years while caudate 18F‐dopa uptake declined by a mean annual rate of 2 %. The asymptomatic heterozygote gene carriers showed a mean 0.56% annual reduction in putamen and 0.62 % annual reduction in caudate 18F‐dopa uptake. Neurological examination at both baseline and follow‐up showed no evidence of parkinsonism. Loss of nigrostriatal dysfunction in parkin‐linked parkinsonism occurs at a very slow rate compared to the 9–12% annual loss of putamen 18F‐dopa uptake reported for idiopathic PD. Although subclinical reductions of striatal 18F‐dopa uptake are common in carriers of a single parkin mutation their slow rate of progression suggests that few if any of these will develop clinical parkinsonism. © 2009 Movement Disorder Society
Neck movement speed in cervical dystonia
Authors: De Beyl Diederik Zegers , Salvia Patrick
Published: October 2009

Clinical scales of patients with cervical dystonia do not rate neck movement velocity. We prospectively measured range of neck movements and movement velocities in 35 consecutive patients with cervical dystonia (CD) and 29 normal controls. Reduction of peak velocities in patients with CD was the most robust abnormality and was correlated to TWSTRS. Coupled movements out of attempted movement plane were increased in the patient group. Movement range was moderately though significantly reduced. We conclude that slowing of voluntary neck movements is a frequent and hitherto unrecognized feature in CD. © 2009 Movement Disorder Society
Numerical local analysis of relevant internal variables for constitutive modelling of granular materials
Authors: Yunus Yuhanis , Vincens Eric , Cambou Bernard
Published: October 2009

DEM simulations on spherical materials have been performed to study the behaviour of model granular materials not only under monotonous stress path such as triaxial compression or extension, but also under two‐way cycling loading paths. Three reference states have been considered to characterize the behaviour of the granular material: the characteristic state, transitory state between volumetric contraction and dilation, the state of maximum resistance and the critical state. These states are regarded with respect to void ratio and anisotropy of fabric which are the two internal variables retained for the description of the internal state of the material. The characteristic state and the state at maximum resistance are clearly dependent on both levels of density and anisotropy at the beginning of a loading path. Bilinear models involving the two internal variables were designed for the characteristic state, the maximum dilatancy and the extent of the dilatancy domain for axisymetric loadings. They show that in each case the effect of density and anisotropy are different in compression and extension. The influence of anisotropy and density seems to be of the same order of magnitude. Copyright © 2009 John Wiley & Sons, Ltd.
High conducting multilayer films from poly(acrylic acid) and graphite by layer‐by‐layer self‐assembly
Authors: Tang Qunwei , Li Qinghua , Lin Jianming , Fan Shijun , Hu De , Wu Jihuai
Published: October 2009

Exfoliated graphite nanoplatelets were modified by hexadecyltrimethylammonium bromide (C16TAB) and were used for the construction of [poly(acrylic acid)/graphite]n [(PAA/G)n] multilayer films using a layer‐by‐layer (LBL) self‐assembly method. The film thickness was monitored using X‐ray diffraction technique; the results showed that the thickness depended on pH of PAA. Under a lower pH value such as 1.5, the average bilayer thickness was 1.5 nm. Once the pH of PAA was increased to 6.5, the bilayer thickness was around 30 nm. The C16TAB modified (PAA/G)n multilayer films showed high thermal stability and electrical conductivity. A percolation phenomenon occurred at bilayer number of 11, and the mechanism was discussed. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Influence of yarn texture on the mechanical properties of textile composite castings
Authors: Zadhoush A. , Sheikhzadeh M. , Elahidust A. , Pirzadeh E.
Published: October 2009

In this research, mechanical properties of textile composite castings used for immobilizing a damaged limb have been studied. For this purpose, a fabric composite was made using a new knitted fabric and textured yarn for the first time. This composite possesses suitable mechanical properties. Mechanical and physical properties such as tensile, bending, and thickness of materials were studied. Results indicate that the use of textured yarns instead of flat yarns increases the amount of resin retainment in fabrics. Furthermore, it decreases tensile modulus and bending modulus of fabrics. Properties of the castings produced were compared with a valid commercial casting. Sample with textured warp and weft, with linear density of 1,500 den of weft, had the best physical and mechanical properties among produced samples. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Dynamic mechanical analysis of oil palm microfibril‐reinforced acrylonitrile butadiene rubber composites
Authors: Joseph Shaji , Sreekumar P.A. , Kenny Jose M. , Puglia Debora , Thomas Sabu , Joseph Kuruvilla
Published: October 2009

The dynamic mechanical properties of microfibers of oil palm‐reinforced acrylonitrile butadiene rubber (NBR) composites were investigated as a function of fiber content, temperature, treatment, and frequency. The storage modulus (E′) was found to increase with weight fraction of microfibrils due to the increased stiffness imparted by the strong adhesion between the polar matrix and the hydrophilic microfibrils. The damping properties were found to decrease with increase in fiber loading. As the fiber content increases, the damping nature of the composite decreases because of the increased stiffness imparted by the natural fibers. By steam explosion method (STEX), microfibrils are separated from fibers. Natural fibers were undergone treatment such as mercerization, benzoylation, and silane treatment. The NBR is modified by the addition of resorcinol‐hexa‐hydrated silica (HRH) bonding agent. Also dicumyl peroxide (DCP) is used as an alternating vulcanizing agent in the system. In the case of composites containing chemically modified fibers, storage modulus were found to increase. Cole–Cole analysis was made to study the phase behavior of the composite samples. Activation energy for the relaxation processes in different composites was calculated. Morphological studies using scanning electron microscopy of tensile fracture surfaces of treated and untreated composites indicated better fiber matrix/adhesion in the case of treated microfibril‐reinforced composites. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Synthesis, electrorheology, and creep behaviors of in situ intercalated polyindole/organo‐montmorillonite conducting nanocomposite
Authors: Erol Ozlem , Unal H. Ibrahim , Sari Bekir
Published: October 2009

In this study, first polyindole (PIN) was synthesized using FeCl3 as an oxidizing agent. Then, an organo‐montmorillonite (O‐MMT) was prepared from virgin montmorillonite (MMT) by cetyltrimethylammonium bromide (CTAB) quaternary ammonium salt. Further, PIN/O‐MMT conducting nanocomposite was prepared with 18% O‐MMT content. The samples of PIN, MMT, O‐MMT, and PIN/O‐MMT nanocomposite were characterized by FTIR spectroscopy, thermogravimetric analysis (TGA), X‐ray diffraction (XRD), elemental analysis, conductivity, magnetic susceptibility, density, particle size measurements, and scanning electron microscopy (SEM) method. Characterization results showed a successfully prepared PIN/O‐MMT nanocomposite having both intercalated and exfoliated structures. A series of concentrations (5–25%, m/m) were prepared from those above‐mentioned materials in silicone oil (SO) and their sedimentation stabilities were determined. The suspensions were subjected to an external electric field strength and electrorheological (ER) activity was observed. The effects of dispersed particle concentration, shear rate, external electric field strength, frequency, and temperature onto ER activities of these suspensions were investigated. Creep tests were applied to all the four suspensions and recoverable viscoelastic deformations observed. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Properties of kenaf fiber/polylactic acid biocomposites plasticized with polyethylene glycol
Authors: Taib Razaina Mat , Ramarad Suganti , Ishak Zainal Arifin Mohd , Todo Mitsugu
Published: October 2009

Biocomposites of kenaf fiber (KF) and polylactic acid (PLA) were prepared by an internal mixer and compression molding. PLA was plasticized with polyethylene glycol (PEG) (10 wt%) and evaluated as the polymer matrix (p‐PLA). Fiber loadings were varied between 0 and 40 wt%. The tensile, dynamic mechanical, and morphological properties and water absorption behavior of these composites were studied. Reinforcing effect of KF was observed when fiber loading exceeded 10 wt% despite of the inferior fiber‐matrix adhesion observed via scanning electron microscopy (SEM). Un‐plasticized PLA/KF composite exhibited higher tensile properties than its plasticized counterpart. Fiber breakage and heavily coated short pulled‐out of fibers were observed from the SEM micrographs of the composite. The presence of PEG might have disturbed the fiber‐matrix interaction between KF and PLA in the plasticized composites. Addition of PEG slightly improved the un‐notched impact strength of the composites. Dynamic mechanical analysis showed that the storage and loss moduli of p‐PLA/KF composites increased with the increase in fiber loading due to increasing restrictions to mobility of the polymer molecules. The tan delta of the composites in contrast showed an opposite trend. p‐PLA and p‐PLA/KF composites exhibited non‐Fickian behavior of water absorption. SEM examination revealed microcracks on p‐PLA and p‐PLA/KF surfaces. POLYM. COMPOS., 31:1213–1222, 2010. © 2009 Society of Plastics Engineers
Extrusion of polyethylene/polypropylene blends with microfibrillar‐phase morphology
Authors: Polaskova Martina , Cermak Roman , Sedlacek Tomas , Kalus Jakub , Obadal Martin , Saha Petr
Published: October 2009

Extrusion of immiscible polymers under special conditions can lead to creation of microfibrillar‐phase morphology, ensuring significant increase of mechanical properties of polymer profiles. Polyethylene/polypropylene blend extrudates with microfibrillar‐phase morphology (polypropylene microfibrils reinforcing polyethylene matrix phase) were prepared through continuous extrusion with semihyperbolic‐converging die enabling elongation and orientation of microfibrils in flow direction. Structure of extruded profiles was examined using electron microscopy and wide‐angle X‐ray scattering. Tensile tests proved that extrudates with microfibrillar‐phase morphology show significantly higher mechanical properties than the conventional extrudates. The presented concept offers possibility of replacing the existing expensive multi‐component medical devices with fully polymeric tools. POLYM. COMPOS., 31:1427–1433, 2010. © 2009 Society of Plastics Engineers
Cytohistological and phytochemical study of madder root extracts obtained by ultrasonic and classical extractions
Authors: Cuoco Guillaume , Mathe Carole , Archier Paul , El Maâtaoui Mohamed , Vieillescazes Cathy
Published: October 2009

Introduction – Madder (Rubia tinctorum) has been used since ancient times as a source of pigments for dyeing and painting. Madder dyes are localised in roots and the native chemical population is composed of glycosiled and aglycone compounds. The aim of this study is to elaborate an efficient extraction process without any chemical denaturation of dyes.

Objective – To compare an optimised ultrasonic process, using for madder dye extraction, with two conventional procedures and to determine the efficiency of ultrasound on these vegetable matrix.

Methodology – Madder roots were extract in a methanol–water mixture in 37 : 63 (v/v) for ultrasound and 80 : 20 (v/v) for reflux and agitation. HPLC‐PAD analyses showed the anthraquinone proportion for each extraction process and their denaturing effects. Finally, cytohistological observations were made to show the consequence of each process on the cell organisation in madder roots.

Results – The results showed that the amount of extracted dyes was higher with UAE than with agitation and reflux. HPLC‐PAD analysis revealed that the anthraquinone composition differed according to the extraction procedure. The UAE extracts presented an important richness in terms of anthraquinonic compounds that suggests a preserving effect. Cytohistological observations showed that the main alterations concerned the cell walls of phloem. After UAE the walls exhibited numerous pitted areas reflecting an ultrasound‐induced cavitation that enhances the extraction effectiveness of this method.

Conclusion – The study has shown the improvement of madder roots extraction both quantitatively and qualitatively using the efficiency of ultrasound‐assisted extraction in comparison with magnetic agitation and reflux techniques. Copyright © 2009 John Wiley & Sons, Ltd.
Placental protein 13 as a first trimester screening marker for aneuploidy
Authors: Koster M. P. H. , Wortelboer E. J. , Cuckle H. S. , Stoutenbeek Ph. , Visser G. H. A. , Schielen P. C. J. I.
Published: October 2009

Objective

To determine whether Placental Protein 13 (PP13) could be an additional marker in first trimester screening for aneuploidies.

Methods

To evaluate differences in multiples of the gestation‐specific normal median (MoMs), PP13 concentrations were measured in serum samples from Down syndrome, trisomy 18 and 13 affected pregnancies and euploid singleton pregnancies (four for each case matched for duration of storage, maternal weight and age).

Results

The PP13 MoM in Down syndrome cases (n = 153) was 0.91 [not statistically significant from controls (n = 853); P = 0.06; Wilcoxon rank sum test, two‐tail]. PP13 MoMs were decreased in trisomy 18 (n = 38—median MoM 0.64; P < 0.0001) and trisomy 13 cases (n = 23—median MoM 0.46; P < 0.0001). There was a slight upward trend in MoM values of the Down syndrome cases with gestational weeks. The PP13 MoM was significantly correlated with the pregnancy associated plasma protein‐A MoM and the free β‐subunit of human chorion gonadotrophin (fβ‐hCG) MoM.

Conclusion

PP13 does not seem to be a good marker for Down syndrome. PP13 MoMs are, however, significantly lower in trisomy 18 and 13 pregnancies. The addition of PP13 to the current screening test could be valuable for improving the discrimination of aneuploid from euploid pregnancies. Copyright © 2009 John Wiley & Sons, Ltd.
Recent permafrost degradation in bogs of the James Bay area, northern Quebec, Canada
Authors: Thibault Simon , Payette Serge
Published: October 2009

Small palsas with very thin frozen layers are present within the peat deposits east of James Bay. Most of these permafrost landforms are in an advanced stage of decay within raised bogs between 51°45′N and 55°N. Air photographs, air‐borne surveys and ground‐truthing of permafrost indicate a recent northward recession of the permafrost boundary by about 130 km, most of which likely happened in the past 50 years. Copyright © 2009 John Wiley & Sons, Ltd.
Raman scattering from ferrocene encapsulated in narrow diameter carbon nanotubes
Authors: Plank W. , Kuzmany H. , Pfeiffer R. , Saito T. , Iijima S.
Published: October 2009

We studied peapods prepared with ferrocene (dicyclopentadienyl iron, Fe(Cp)2) as filling species, which makes CNTs with diameters down to 1.1 nm accessible for filling. Two different single‐wall carbon nanotube (SWCNT) samples with mean diameters of 1.1 nm (HiPco) and 1.6 nm (DIPS) were used. Filling was done from the gas phase at elevated temperatures. Sample analysis was done by multifrequency Raman spectroscopy.

The Raman response from the encapsulated molecule could be observed through the wall of the CNTs, confirming the encapsulation of the employed molecular species. We observed a sharp decrease of the radial breathing mode intensity for the peapod samples compared to the unfilled CNTs. Ferrocene peapods were transformed to double wall carbon nanotubes (DWCNTs) in a heat induced growth process.
Prediction of HIV‐1 Protease Inhibitors Using Machine Learning Approaches
Authors: Rao Hanbing , Yang Guobing , Tan Ningxin , Li Ping , Li Zerong , Li Xiangyuan
Published: October 2009

In this study, multiple machine learning approaches, including support vector machine (SVM), k‐nearest neighbor (k‐NN), artificial neural networks (ANN) and logistic regression (LR), are applied for classification of HIV‐1 protease inhibitors(PIs) from molecular structure. A diverse set of 641 compounds, including 414 active agents (PIs+) and 227 inactive agents (PIs−), are adopted to develop the classification models. A hybrid feature selection method, which combines Fischer's score and Monte Carlo simulated annealing embedded in the support vector machine approach, is used to select the relevant descriptors from a pool of 1559 molecular descriptors. Three validation methods are employed to validate the model in this study. The first one is the five‐fold cross validation method and the averaged prediction accuracies for these machine learning approaches are between 83.9–93.5% for PIs+and between 67.0–77.7% for PIs−agents. The second validation method is the external test set and the prediction accuracies for PIs+are between 84.6–95.2% and for PIs−agents are between 63.2–87.7%. These two validation methods show that the SVM model has better overall performance than other three machine learning models. The third validation method is the y‐scrambling method, which shows no obvious chance correction in the developed SVM model. The prediction method proposed in this work can give better generalization ability than other recently published methods and can be used as an alternative fast filter in the virtual screening of large chemical database.
Facile synthesis of 4‐mercaptophenylboronic acid functionalized gold nanoparticles for selective enrichment of glycopeptides
Authors: Yao Guoping , Zhang Huaiyuan , Deng Chunhui , Lu Haojie , Zhang Xiangmin , Yang Pengyuan
Published: October 2009

In the work, 4‐mercaptophenylboronic acid (4‐MPBA)‐functionalized gold nanoparticles were synthesized via a facile approach. At first, gold nanoparticles (about 50 nm) were prepared by a simple and convenient hydrothermal method based on a polyol process. Then, gold nanoparticles were modified with 4‐MPBA by the well‐known reaction of Au with the thiol groups. The MPBA‐functionalized gold nanoparticles were characterized by Fourier transform infrared spectra and UV/Vis adsorption spectra. Due to the fact that the boronic acid group on the surface of 4‐MPBA‐modified gold particles can form tight yet reversible covalent bonds with glycopeptides containing cis‐1,2‐diols groups, the MPBA‐modified gold nanoparticles were successfully applied to selective enrichment of glycopeptides. Isolation and enrichment of glycopeptides in a standard protein (asialofetuin and horseradish peroxidase) digestion and a complex sample were performed using MPBA‐modified gold nanoparticles, followed by matrix‐assisted laser desorption/ionization quadruple ion trap time‐of‐flight (MALDI‐QIT‐TOF) mass spectrometric analysis. The experimental results demonstrated that MPBA‐modified gold nanoparticles synthesized by the facile approach have the powerful potential for selective enrichment of glyciopeptides, and can be an alternative tool in glycoproteomics. Copyright © 2009 John Wiley & Sons, Ltd.
Use of liquid chromatography/tandem mass spectrometric molecular fingerprinting for the rapid structural identification of pharmaceutical impurities
Authors: Li Min , Wang Xin , Chen Bin , Lin Mingxiang , Buevich Alexei V. , Chan Tze‐Ming , Rustum Abu M.
Published: October 2009

Use of liquid chromatography/tandem mass spectrometric (LC/MSn) molecular fingerprinting is systematically demonstrated as a very effective tool for rapid structural elucidation of pharmaceutical impurities through a case study in which three isomers of betamethasone sodium phosphate (BSP) were rapidly identified as degradants formed due to the D‐homoannular ring expansion of the steroid core structure of BSP in the solid state. The rapid structural elucidation of these degradants was achieved by matching or closely matching the UV profiles, molecular weights, and more importantly the fragmentation patterns obtained from the LC/MSn (n = 1 to 3) analysis of their enzyme‐catalyzed hydrolytic products, respectively, with those of a D‐homoannular isomer of betamethasone available in our LC/MSn molecular fingerprint database. This strategy of using LC/MSn molecular fingerprinting to obtain high‐confidence structures of unknown species is then validated by structure verification through one‐ (1D) and two‐dimensional (2D) nuclear magnetic resonance (NMR) experiments. Copyright © 2009 John Wiley & Sons, Ltd.
Nicotine, acetanilide and urea multi‐level 2H‐, 13C‐ and 15N‐abundance reference materials for continuous‐flow isotope ratio mass spectrometry
Authors: Schimmelmann Arndt , Albertino Andrea , Sauer Peter E. , Qi Haiping , Molinie Roland , Mesnard François
Published: October 2009

Accurate determinations of stable isotope ratios require a calibration using at least two reference materials with different isotopic compositions to anchor the isotopic scale and compensate for differences in machine slope. Ideally, the δ values of these reference materials should bracket the isotopic range of samples with unknown δ values. While the practice of analyzing two isotopically distinct reference materials is common for water (VSMOW‐SLAP) and carbonates (NBS 19 and L‐SVEC), the lack of widely available organic reference materials with distinct isotopic composition has hindered the practice when analyzing organic materials by elemental analysis/isotope ratio mass spectrometry (EA‐IRMS). At present only L‐glutamic acids USGS40 and USGS41 satisfy these requirements for δ13C and δ15N, with the limitation that L‐glutamic acid is not suitable for analysis by gas chromatography (GC). We describe the development and quality testing of (i) four nicotine laboratory reference materials for on‐line (i.e. continuous flow) hydrogen reductive gas chromatography‐isotope ratio mass‐spectrometry (GC‐IRMS), (ii) five nicotines for oxidative C, N gas chromatography‐combustion‐isotope ratio mass‐spectrometry (GC‐C‐IRMS, or GC‐IRMS), and (iii) also three acetanilide and three urea reference materials for on‐line oxidative EA‐IRMS for C and N. Isotopic off‐line calibration against international stable isotope measurement standards at Indiana University adhered to the ‘principle of identical treatment’. The new reference materials cover the following isotopic ranges: δ2Hnicotine −162 to −45‰, δ13Cnicotine −30.05 to +7.72‰, δ15Nnicotine −6.03 to +33.62‰; δ15Nacetanilide +1.18 to +40.57‰; δ13Curea −34.13 to +11.71‰, δ15Nurea +0.26 to +40.61‰ (recommended δ values refer to calibration with NBS 19, L‐SVEC, IAEA‐N‐1, and IAEA‐N‐2). Nicotines fill a gap as the first organic nitrogen stable isotope reference materials for GC‐IRMS that are available with different δ15N values. Comparative δ13C and δ15N on‐line EA‐IRMS data from 14 volunteering laboratories document the usefulness and reliability of acetanilides and ureas as EA‐IRMS reference materials. Published in 2009 by John Wiley & Sons, Ltd.
Validation of deuterium and oxygen18 in urine and saliva samples from children using on‐line continuous‐flow isotope ratio mass spectrometry
Authors: Schierbeek H. , Rieken R. , Dorst K. Y. , Penning C. , van Goudoever J. B.
Published: October 2009

The doubly labelled water method is valuable for measuring energy expenditure in humans. It usually involves blood or urine sampling, which might be difficult in neonates and children with cerebral palsy or other disabilities. We therefore aimed to validate a method making use of saliva samples analyzed by automated thermal conversion elemental analyzer in combination with isotope ratio mass spectrometry (TC‐EA/IRMS). The subjects received labelled water orally and urine and saliva samples were collected and analyzed. Deuterium as well as oxygen18 was measured in one single run using a peak jump method. Excellent linearity was found for measurement of enrichments of deuterium (R2 = 0.9999) and oxygen18 (R2 = 0.9999). The intra‐assay precision and the inter‐assay precision of the measurement of two standards were good for both deuterium and oxygen18. The variation between urine and saliva samples was small (4.83% for deuterium and 2.33% for oxygen18 n = 40). Saliva sampling is to be preferred, therefore, as it can be easily collected and is non‐invasive. Moreover, its time of production is almost exactly known. The TC‐EA/IRMS method is a good alternative to the more laborious off‐line IRMS measurements. Copyright © 2009 John Wiley & Sons, Ltd.
Use of ion mobility mass spectrometry and a collision cross‐section algorithm to study an organometallic ruthenium anticancer complex and its adducts with a DNA oligonucleotide
Authors: Williams Jonathan P. , Lough Julie Ann , Campuzano Iain , Richardson Keith , Sadler Peter J.
Published: October 2009

We report the development of an enhanced algorithm for the calculation of collision cross‐sections in combination with Travelling‐Wave ion mobility mass spectrometry technology and its optimisation and evaluation through the analysis of an organoruthenium anticancer complex [(η6‐biphenyl)RuII(en)Cl]+. Excellent agreement was obtained between the experimentally determined and theoretically determined collision cross‐sections of the complex and its major product ion formed via collision‐induced dissociation. Collision cross‐sections were also experimentally determined for adducts of this ruthenium complex with the single‐stranded oligonucleotide hexamer d(CACGTG). Ion mobility tandem mass spectrometry measurements have allowed the binding sites for ruthenium on the oligonucleotide to be determined. Copyright © 2009 John Wiley & Sons, Ltd.
A hydrogeomorphic dynamics approach to assess in‐stream ecological functionality using the functional flows model, part 1—model characteristics
Authors: Escobar‐Arias M. I. , Pasternack Gregory B.
Published: October 2009

The functional flows model integrates hydrogeomorphic processes and ecological functions for stream physical habitat evaluations. Functional flows are discharge values that serve ecological uses. Assessments of functional flows are based on evaluation of shear stress dynamics. The analysis is based on the occurrence of sediment transport regimes defined by threshold values of Shields stress estimated from discharge (Q), a parameter (f) governing depth response to incremental discharge changes, water surface slope (S) and media grain size (D50). As an example, the model was tuned for fall‐run Chinook salmon spawning. Ecological functions studied were bed occupation (spawning, incubation and emergence) and bed preparation (river bed reworking periods)—both reliant on shear stress dynamics. A numerical experiment and sensitivity analysis using a wide range of realistic values of input variables indicated the effect of each variable on flow functionality. Combinations of S = 0.001, 0.005 and 0.01, D50 = 0.02, 0.05, 0.1 m, f = 0.2, 0.3, 0.4, 0.5 and four sediment transport stages produced 144 scenarios. Ranges of functional flows were greater for scenarios for low f (0.2) with low slope (0.001,0.05), for high f (0.5) with small grain size (0.02 m) and for intermediate low f (0.3) with coarse grain size (0.1 m). The functional flows model incorporates in‐stream habitat processes by including metrics of hydrologic, hydraulic, geomorphic and ecologic dynamics. Model uncertainties related to input data, calculation algorithms, and model structure are analysed. Functional flows analysis can be useful in studying water management alternatives to improve habitat conditions for target species and lifestages. Copyright © 2009 John Wiley & Sons, Ltd.
Reasoning up and down a food chain: Using an assessment framework to investigate students' middle knowledge
Authors: Gotwals Amelia Wenk , Songer Nancy Butler
Published: October 2009

Being able to make claims about what students know and can do in science involves gathering systematic evidence of students' knowledge and abilities. This paper describes an assessment system designed to elicit information from students at many placements along developmental trajectories and demonstrates how this system was used to gather principled evidence of how students reason about food web and food chain disturbances. Specifically, this assessment system was designed to gather information about students' intermediary or middle knowledge on a pathway toward more sophisticated understanding. Findings indicate that in association with a curricular intervention, student gains were significant. However, despite overall gains, some students still struggled to explain what might happen during a disturbance to an ecosystem. In addition, this paper discusses the importance of having a cognitive framework to guide task design and interpretation of evidence. This framework allowed for the gathering of detailed information, which provided insights into the intricacies of how students reason about scientific scenarios. In particular, this assessment system allowed for the illustration of multiple types of middle knowledge that students may possess, indicating that there are multiple “messy middles” students may move through as they develop the ability to reason about complex scientific situations. © 2009 Wiley Periodicals, Inc. Sci Ed 94:259–281, 2010
Synthesis of High Coercivity Core–Shell Nanorods Based on Nickel and Cobalt and Their Magnetic Properties
Authors: Narayanan TN , Shaijumon MM , Ajayan PM , Anantharaman MR
Published: October 2009

Hybrid magnetic nanostructures with high coercivity have immense application potential in various fields. Nickel (Ni) electrodeposited inside Cobalt (Co) nanotubes (a new system named Ni @ Co nanorods) were fabricated using a two-step potentiostatic electrodeposition method. Ni @ Co nanorods were crystalline, and they have an average diameter of 150 nm and length of ~15 μm. The X-ray diffraction studies revealed the existence of two separate phases corresponding to Ni and Co. Ni @ Co nanorods exhibited a very high longitudinal coercivity. The general mobility-assisted growth mechanism proposed for the growth of one-dimensional nanostructures inside nano porous alumina during potentiostatic electrodeposition is found to be valid in this case too.
Common before-after accident study on a road site: a low-informative Bayesian method
Authors: Brenac Thierry
Published: October 2009

Purpose

This note aims at providing a Bayesian methodological basis for routine before-after accident studies, often applied to a single road site, and in conditions of limited resources in terms of time and expertise.

Methods

A low-informative Bayesian method is proposed for before-after accident studies using a comparison site or group of sites. As compared to conventional statistics, the Bayesian approach is less subject to misuse and misinterpretation by practitioners. The low-informative framework seems appropriate in situations of limited expertise. The proposed approach gives the possibility of correcting for regression to the mean. Examples illustrate the application of this method.

Results and conclusions

It is shown that a relatively simple method, based on the Jeffreys’s rule prior considered as a “reasonable standard”, can be implemented without major difficulties. Posterior distributions are proper. The numerical calculation of posterior probabilities can be done without using Monte-Carlo simulations nor specialised software tools.
Effects of oats on plasma cholesterol and lipoproteins in C57BL/6 mice are substrain specific
Authors: Andersson Kristina E. , Immerstrand Tina , Swärd Karl , Bergenståhl Björn , Lindholm Marie W. , Öste Rickard , Hellstrand Per
Published: October 2009

Cholesterol-lowering effects of oats have been demonstrated in both animals and human subjects. However, the crucial properties of oat-containing diets that determine their health effects need to be further investigated to optimise their use. A mouse model would be a valuable tool, but few such studies have been published to date. We investigated the effects of oat bran on plasma cholesterol and lipoproteins in two substrains of C57BL/6 mice. Western diet was made atherogenic by the addition of 0·8 % cholesterol and 0·1 % cholic acid. After 4 weeks on atherogenic diet, total plasma cholesterol had increased from 1·86–2·53 to 3·77–4·40 mmol/l. In C57BL/6NCrl mice, inclusion of 27 and 40 % oat bran reduced total plasma cholesterol by 19 and 24 %, respectively, reduced the shift from HDL to LDL+VLDL and caused increased faecal cholesterol excretion. There was no effect of oat bran on plasma levels of the inflammatory markers fibrinogen, serum amyloid A or TNF-α. Contrary to findings in C57BL/6NCrl mice, there was no sustained effect of oat bran (27 or 40 %) on plasma cholesterol in C57BL/6JBomTac mice after 4 weeks of feeding. Thus, C57BL/6NCrl mice fed an atherogenic diet are a good model for studies of physiological effects of oats, whereas a substrain derived from C57BL/6J, raised in a different breeding environment and likely possessing functional genetic differences from C57BL/6N, is considerably less responsive to oats. The present finding that two substrains of mice respond differently to oats is of practical value, but can also help to elucidate mechanisms of the cholesterol-lowering effect of oats.
Assessing dietary intake in a population undergoing a rapid transition in diet and lifestyle: the Arctic Inuit in Nunavut, Canada
Authors: Sharma Sangita , Cao Xia , Roache Cindy , Buchan Annie , Reid Rhonda , Gittelsohn Joel
Published: October 2009

The aims of the present study were to (1) characterise the diets of adult Inuit; (2) highlight foods for a nutritional and lifestyle intervention programme; (3) develop a quantitative FFQ (QFFQ) to evaluate the programme and monitor changes in dietary intake in this population over time. A dietary survey using single 24-h dietary recalls was conducted among Inuit aged between 19 and 87 years in two communities in Nunavut, Canada. Eighty-seven subjects completed the recalls (response rate was approximately 73 %). The mean energy intake for men and women was 9530 and 6939 kJ, respectively. The intakes of dietary fibre and the majority of vitamins and minerals (especially vitamins A, D, and E, total folate and Ca) were far below the recommendations. Traditional foods contributed 40 and 42 %, respectively, to protein and Fe intakes. Non-nutrient-dense store-bought foods were consumed much more frequently than the nutrient-dense traditional foods. Foods high in fat and sugar were highlighted, and will be replaced by healthier, more nutrient-dense alternatives to address the dietary inadequacies for the nutritional intervention programme. A 154-item QFFQ was developed and pilot tested in the Arctic Inuit. The present study highlighted foods to be targeted for a nutritional and lifestyle intervention programme not previously undertaken in this population. This QFFQ is culturally appropriate and specific for evaluating the effectiveness of the programme, as well as monitoring nutritional transition in this population.
On the energetics of stratified turbulent mixing, irreversible thermodynamics, Boussinesq models and the ocean heat engine controversy
Authors: TAILLEUX RÉMI
Published: October 2009

In this paper, the available potential energy (APE) framework of Winters et al. (J. Fluid Mech., vol. 289, 1995, p. 115) is extended to the fully compressible Navier–Stokes equations, with the aims of clarifying (i) the nature of the energy conversions taking place in turbulent thermally stratified fluids; and (ii) the role of surface buoyancy fluxes in the Munk & Wunsch (Deep-Sea Res., vol. 45, 1998, p. 1977) constraint on the mechanical energy sources of stirring required to maintain diapycnal mixing in the oceans. The new framework reveals that the observed turbulent rate of increase in the background gravitational potential energy GPEr, commonly thought to occur at the expense of the diffusively dissipated APE, actually occurs at the expense of internal energy, as in the laminar case. The APE dissipated by molecular diffusion, on the other hand, is found to be converted into internal energy (IE), similar to the viscously dissipated kinetic energy KE. Turbulent stirring, therefore, does not introduce a new APE/GPEr mechanical-to-mechanical energy conversion, but simply enhances the existing IE/GPEr conversion rate, in addition to enhancing the viscous dissipation and the entropy production rates. This, in turn, implies that molecular diffusion contributes to the dissipation of the available mechanical energy ME = APE + KE, along with viscous dissipation. This result has important implications for the interpretation of the concepts of mixing efficiency γmixing and flux Richardson number Rf, for which new physically based definitions are proposed and contrasted with previous definitions.

The new framework allows for a more rigorous and general re-derivation from the first principles of Munk & Wunsch (1998, hereafter MW98)'s constraint, also valid for a non-Boussinesq ocean:

where G(KE) is the work rate done by the mechanical forcing, Wr, forcing is the rate of loss of GPEr due to high-latitude cooling and ξ is a nonlinearity parameter such that ξ = 1 for a linear equation of state (as considered by MW98), but ξ < 1 otherwise. The most important result is that G(APE), the work rate done by the surface buoyancy fluxes, must be numerically as large as Wr, forcing and, therefore, as important as the mechanical forcing in stirring and driving the oceans. As a consequence, the overall mixing efficiency of the oceans is likely to be larger than the value γmixing = 0.2 presently used, thereby possibly eliminating the apparent shortfall in mechanical stirring energy that results from using γmixing = 0.2 in the above formula.
Carbon dioxide laser cordectomy for verrucous carcinoma of vocal folds
Authors: Hod R , Feinmesser R , Shvero J
Published: October 2009

Background:

Verrucous carcinoma occurs infrequently in the vocal folds. This tumour has an excellent prognosis with proper treatment. Management strategies include surgery, radiotherapy or both.

Aim:

To evaluate the long-term results of type I and II laser cordectomy for the treatment of verrucous carcinoma of the vocal folds.

Materials and methods:

We reviewed the files of 18 patients with verrucous carcinoma of the vocal folds treated by type I or II laser cordectomy in our department from 1989 to 2006, and recorded clinical and outcome data.

Results:

None of the patients had any major post-operative complications. All had a subjectively satisfactory quality of voice, with no morbidity. Patient follow up ranged from three to 228 months (mean, 48 months). Five patients were treated with post-operative radiotherapy for persistent disease, of whom four underwent repeated surgery due to recurrence.

Conclusion:

Type I or II laser cordectomy is a safe, feasible, secure method of treating verrucous carcinoma of the vocal folds. There were no major complications in our patient series. Most recurrent disease was manageable locally with repeated surgery.
Meningocoele of fallopian canal causing recurrent meningitis
Authors: Dhanasekar G , Pearman K , Irving R
Published: October 2009

Objective:

We report a rare case of meningocoele of the fallopian canal resulting in recurrent meningitis.

Methods:

We present a case report together with a review of the world literature concerning meningocoele of the fallopian canal and meningitis.

Results:

A child developed profound, bilateral, sensorineural hearing loss as a result of meningitis caused by a meningocoele of the fallopian canal. He was treated with bilateral cochlear implantation, with a subtotal petrosectomy and middle ear and eustachian tube obliteration on the affected side.

Conclusion:

Meningocoele of the fallopian canal has rarely been reported. This lesion can present with recurrent meningitis and, rarely, with facial weakness. All children with recurrent meningitis should be investigated for skull base defects. Treatment aims to prevent further episodes of meningitis; we recommend that this is best achieved by the technique of subtotal petrosectomy, with obliteration of the middle ear and eustachian tube.
Latent superior canal dehiscence syndrome unmasked by stapedotomy for otosclerosis
Authors: Hope A , Fagan P
Published: October 2009

Objective:

This report describes a novel case in which superior canal dehiscence syndrome was unmasked by successful stapes surgery for otosclerosis.

Methods:

Case report and literature review regarding superior canal dehiscence syndrome.

Introduction:

Superior canal dehiscence syndrome is a rare but well described condition in which audiovestibular symptoms are caused by noise or straining. A dehiscence of the superior semicircular canal in the floor of the middle cranial fossa is responsible, and acts as a ‘third window’ into the inner ear.

Case history:

A patient with confirmed otosclerosis underwent second-side stapedotomy, with good audiometric outcomes. Unfortunately, surgery was complicated by immediate post-operative vertigo and persistent auditory symptoms. A diagnosis of superior canal dehiscence syndrome was eventually made, on the basis of low threshold vestibular evoked myogenic potentials and characteristic computed tomography findings. Superior canal resurfacing resulted in complete resolution of symptoms.

Discussion:

The otosclerotic focus in the oval window prevented the development of symptoms from this patient's superior canal dehiscence syndrome. Surgical stapedotomy created a third window and resulted in immediate post-operative imbalance and auditory symptoms.

Conclusion:

The diagnosis of superior canal dehiscence syndrome should be considered in patients with persistent audiovestibular symptoms after stapes surgery. High resolution computed tomography of the temporal bone and vestibular evoked myogenic potential testing, if available, are the investigations of choice in confirming the diagnosis.
Sing a song of difference: Connie Boswell and a discourse of disability in jazz
Authors: STRAS LAURIE
Published: October 2009

Although a wheelchair-user and permanently disabled through polio, the southern American singer Connie Boswell was one of radio and vaudeville's biggest stars in the 1930s. She and her sisters were a compelling force in American popular entertainment for the first half of the decade; and when the group split in 1936, Connie carried on a solo career in radio, recording, film and television for another twenty-five years. Connie's unique position as the only visibly disabled ‘A-list’ female popular entertainer for most of the twentieth century – and one whose voice, both physical and musical, shaped the sound of jazz and popular music – makes her an obvious focus for any study that links popular music and disability. This essay is concerned with how disability may have operated as a discourse about and within Connie's chosen medium, jazz; and how disability studies can illuminate why the ways in which difference is figured in her work, initially a source of anxiety, could have also been a significant reason for her success.