bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanoband electrode for high‐performance in‐channel amperometric detection in dual‐channel microchip capillary electrophoresis
Authors: Chen Chuanpin , Teng Wei , Hahn Jong Hoon
Published: March 2011

A nanoband electrode detector integrated with a dual‐channel polydimethylsiloxane microchip is proposed for in‐channel amperometric detection in microchip capillary electrophoresis. Gold nanoband electrodes, which were fabricated on SU‐8 substrates with a 100‐nm‐width gold layer, were introduced into the dual‐channel microchip to be an electrochemical detector. Due to the nano‐sized width of the detector, the noise of the amperometric detection was significantly reduced, and a high separation resolution was achieved for monitoring the analytes. The detection sensitivity of the system was improved by high signal‐to‐noise ratio, and a low detection limit on microchip was obtained for p‐aminophenol (2.09 nM). Because of the high resolution in measuring half‐peak width, the plate number that is used to evaluate the separation efficiency was 1.5‐fold higher than that using 50‐μm‐width electrochemical detector. The effect of sample injection time and data acquisition time on separation efficiency was investigated, and an attractive separation efficiency was achieved with a plate number up to 17 500.
Numerical simulation of laminar flow past a circular cylinder with slip conditions
Authors: Seo Il Won , Song Chang Geun
Published: March 2011

The no‐slip condition is an assumption that cannot be derived from first principles and a growing number of literatures replace the no‐slip condition with partial‐slip condition, or Navier‐slip condition. In this study, the influence of partial‐slip boundary conditions on the laminar flow properties past a circular cylinder was examined. Shallow‐water equations are solved by using the finite element method accommodating SU/PG scheme. Four Reynolds numbers (20, 40, 80, and 100) and six slip lengths were considered in the numerical simulation to investigate the effects of slip length and Reynolds number on characteristic parameters such as wall vorticity, drag coefficient, separation angle, wake length, velocity distributions on and behind the cylinder, lift coefficient, and Strouhal number. The simulation results revealed that as the slip length increases, the drag coefficient decreases since the frictional component of drag is reduced, and the shear layer developed along the cylinder surface tends to push the separation point away toward the rear stagnation point so that it has larger separation angle than that of the no‐slip condition. The length of the wake bubble zone was shortened by the combined effects of the reduced wall vorticity and wall shear stress which caused a shift of the reattachment point closer to the cylinder. The frequency of the asymmetrical vortex formation with partial slip velocity was increased due to the intrinsic inertial effect of the Navier‐slip condition. Copyright © 2011 John Wiley & Sons, Ltd.
Regional brain volume reductions relate to facial dysmorphology and neurocognitive function in fetal alcohol spectrum disorders
Authors: Roussotte Florence F. , Sulik Kathleen K. , Mattson Sarah N. , Riley Edward P. , Jones Kenneth L. , Adnams Colleen M. , May Philip A. , O'Connor Mary J. , Narr Katherine L. , Sowell Elizabeth R.
Published: March 2011

Individuals with heavy prenatal alcohol exposure can experience significant deficits in cognitive and psychosocial functioning and alterations in brain structure that persist into adulthood. In this report, data from 99 participants collected across three sites (Los Angeles and San Diego, California, and Cape Town, South Africa) were analyzed to examine relationships between brain structure, neurocognitive function, facial morphology, and maternal reports of quantities of alcohol consumption during the first trimester. Across study sites, we found highly significant volume reductions in the FASD group for all of the brain regions evaluated. After correcting for scan location, age, and total brain volume, these differences remained significant in some regions of the basal ganglia and diencephalon. In alcohol‐exposed subjects, we found that smaller palpebral fissures were significantly associated with reduced volumes in the ventral diencephalon bilaterally, that greater dysmorphology of the philtrum predicted smaller volumes in basal ganglia and diencephalic structures, and that lower IQ scores were associated with both smaller basal ganglia volumes and greater facial dysmorphology. In subjects from South Africa, we found a significant negative correlation between intracranial volume and total number of drinks per week in the first trimester. These results corroborate previous reports that prenatal alcohol exposure is particularly toxic to basal ganglia and diencephalic structures. We extend previous findings by illustrating relationships between specific measures of facial dysmorphology and the volumes of particular subcortical structures, and for the first time show that continuous measures of maternal alcohol consumption during the first trimester relates to overall brain volume reduction. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
Papillary thyroid carcinoma in black thyroids
Authors: Kandil Emad , Khalek Mohamed Abdel , Ibrahim Wael G. , Alabbas Haytham , Yau C. Lillian , Friedlander Paul , Crawford Byron , Jaffe Bernard M.
Published: March 2011

Background

Black thyroid is a rare condition. It has been considered to be pathognomonic of chronic minocycline ingestion for more than 30 years, although it can also occur in patients with hemochromatosis, ochronosis, mucoviscidosis, and hemorrhage. A possible association of black thyroid with thyroid cancer has been considered, but no direct causal relationship has been established. Hence, the purpose of this article was to identify the malignant potential of such glands.

Methods

A retrospective medical chart review was performed on 433 patients who underwent thyroid surgery at Tulane University Medical Center from 2001 to 2008. Patients were grouped based on pathology: (1) benign, (2) papillary carcinoma, and (3) non‐papillary thyroid carcinoma.

Results

At surgery, 63 patients (15%) with black thyroid gland were found to have thyroid nodules. Among these nodules, 22 (35%) were benign, 21 (33%) contained papillary thyroid cancer, and 20 (32%) had a non‐papillary thyroid malignancy. Nodules in black thyroids were associated with higher risk of malignancy than nodules in non‐black thyroids (p = .0001). Further analysis of the papillary thyroid carcinoma group showed no statistical difference in regard to tumor size or evidence of multifocality of disease.

Conclusion

The finding of a black thyroid gland is unusual and disconcerting. To our knowledge, this is the first study aimed at documenting the malignant potential of black thyroid glands. This report documents that the risk of malignancy is higher in black thyroid compared to non‐black thyroid glands. Furthermore, among those with papillary thyroid cancer, the presence of the pigment did not correlate with malignancy, multifocality, or tumor size. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Realized GARCH: a joint model for returns and realized measures of volatility
Authors: Hansen Peter Reinhard , Huang Zhuo , Shek Howard Howan
Published: March 2011

We introduce a new framework, Realized GARCH, for the joint modeling of returns and realized measures of volatility. A key feature is a measurement equation that relates the realized measure to the conditional variance of returns. The measurement equation facilitates a simple modeling of the dependence between returns and future volatility. Realized GARCH models with a linear or log‐linear specification have many attractive features. They are parsimonious, simple to estimate, and imply an ARMA structure for the conditional variance and the realized measure. An empirical application with Dow Jones Industrial Average stocks and an exchange traded index fund shows that a simple Realized GARCH structure leads to substantial improvements in the empirical fit over standard GARCH models that only use daily returns. Copyright © 2011 John Wiley & Sons, Ltd.
Vitamin D–binding protein modifies the vitamin D–bone mineral density relationship
Authors: Powe Camille E , Ricciardi Catherine , Berg Anders H , Erdenesanaa Delger , Collerone Gina , Ankers Elizabeth , Wenger Julia , Karumanchi S Ananth , Thadhani Ravi , Bhan Ishir
Published: March 2011

Studies examining the relationship between total circulating 25-hydroxyvitamin D [25(OH)D] levels and bone mineral density (BMD) have yielded mixed results. Vitamin D–binding protein (DBP), the major carrier protein for 25(OH)D, may alter the biologic activity of circulating vitamin D. We hypothesized that free and bioavailable 25(OH)D, calculated from total 25(OH)D, DBP, and serum albumin levels, would be more strongly associated with BMD than levels of total 25(OH)D. We measured total 25(OH)D, DBP, and serum albumin levels in 49 healthy young adults enrolled in the Metabolic Abnormalities in College-Aged Students (MACS) study. Lumbar spine BMD was measured in all subjects using dual-energy X-ray absorptiometry. Clinical, diet, and laboratory information also was gathered at this time. We determined free and bioavailable (free + albumin-bound) 25(OH)D using previously validated formulas and examined their associations with BMD. BMD was not associated with total 25(OH)D levels (r = 0.172, p = .236). In contrast, free and bioavailable 25(OH)D levels were positively correlated with BMD (r = 0.413, p = .003 for free, r = 0.441, p = .002 for bioavailable). Bioavailable 25(OH)D levels remained independently associated with BMD in multivariate regression models adjusting for age, sex, body mass index, and race (p = .03). It is concluded that free and bioavailable 25(OH)D are more strongly correlated with BMD than total 25(OH)D. These findings have important implications for vitamin D supplementation in vitamin D–deficient states. Future studies should continue to explore the relationship between free and bioavailable 25(OH)D and health outcomes. © 2011 American Society for Bone and Mineral Research.
Back to the future: Moving beyond “mesenchymal stem cells”
Authors: Bianco Paolo
Published: March 2011

The last decade was dominated by dissemination of the notion that postnatal “mesenchymal stem cells,” found primarily in bone marrow but also in other tissues, can generate multiple skeletal and nonskeletal tissues, and thus can be exploited to regenerate a broad range of tissues and organs. The concept of “mesenchymal stem cells” and its applicative implications represent a significant departure from the solidly proven notion that skeletal stem cells are found in the bone marrow (and not in other tissues). Recent data that sharpen our understanding of the identity, nature, origin, and in vivo function of the archetypal “mesenchymal stem cells” (bone marrow skeletal stem cells) point to their microvascular location, mural cell identity, and function as organizers and regulators of the hematopoietic microenvironment/niche. These advances bring back the original concept from which the notion of “mesenchymal stem cells” evolved, and clarify a great deal of experimental data that accumulated in the past decade. As a novel paradigm emerges that accounts for many facets of the biology of skeletal stem cells, a novel paradigm independently emerges for their applicative/translational use. The two paradigms meet each other back in the future. J. Cell. Biochem. 112: 1713–1721, 2011. © 2011 Wiley‐Liss, Inc.
A comparison of statistical downscaling methods suited for wildfire applications
Authors: Abatzoglou John T. , Brown Timothy J.
Published: March 2011

Place‐based data is required in wildfire analyses, particularly in regions of diverse terrain that foster not only strong gradients in meteorological variables, but also complex fire behaviour. However, a majority of downscaling methods are inappropriate for wildfire application due to the lack of daily timescales and variables such as humidity and winds that are important for fuel flammability and fire spread. Two statistical downscaling methods, the daily Bias corrected Spatial Downscaling (BCSD) and the Multivariate Adapted Constructed Analogs (MACA) that directly incorporate daily data from global climate models, were validated over the western US using global reanalysis data. While both methods outperformed results obtained from direct interpolation from reanalysis, MACA exhibited additional skill in temperature, humidity, wind, and precipitation due to its ability to jointly downscale temperature and dew point temperature, and its use of analog patterns rather than interpolation. Both downscaling methods exhibited value added information in tracking fire danger indices and periods of extreme fire danger; however, MACA outperformed the daily BCSD due to its ability to more accurately capture relative humidity and winds. Copyright © 2011 Royal Meteorological Society
Polymer Nanocomposites from Organoclays: Structure and Properties
Authors: Cui Lili , Paul D.R.
Published: March 2011

Summary: Polymer nanocomposites formed from organically modified montmorillonite offer the promise of greatly improved properties over those of the matrix polymer, provided the organoclay can be dispersed, or exfoliated, into the polymer matrix to generate high aspect ratio particles. The exfoliation of organoclays in two series of ethylene‐based polymers, ethylene‐vinyl acetate copolymers and sodium ionomers of ethylene‐methyacrylic acid copolymers, is described along with the properties of these nanocomposites.
Nanoclays Dispersion in a PA6/PP Blend by Twin Screw Compounding
Authors: Covas J. A. , Almeida M. F. , Machado A. V. , Larocca N. M. , Pessan L. A.
Published: March 2011

Summary: A modified PP and an organoclay (Cloisite C15A, a montmorillonite modified with alkyl ammonium) were incorporated in a PA/PP 70/30 w/w blend by means of twin‐screw melt compounding. The dispersion of the nanoclay into the polymer matrix and its eventual compatibilization effect were investigated by collecting samples along the barrel and characterizing them by X‐ray diffraction (XRD), oscillatory rheometry, scanning and transmission microscopy (SEM and TEM). Chemical and morphological changes occurred mostly during polymer melting. The morphologies of the nanocomposite and of the compatibilized blends were much finer than that of the physical blend. When both the modified PP and the organoclay were present the morphology was even finer, suggesting that the organoclays may produce a compatibilization effect similar to that of PP‐g‐MA.
Spinnability of Nanofilled Polypropylene
Authors: Lorenzi Denis , Sartori Gabriella , Ferrara Giuseppe , Fambri Luca
Published: March 2011

Summary: Spinnability of isotactic polypropylene iPP (melt flow 25 g/10 min) was studied after addition of three nanofillers at 0.3% by wt., two nanoclays and a modified hydrotalcite. TGA evidenced the increase of thermooxidation stability in nanofilled iPPs. All these iPP were successfully processed and tensile properties similar to those of iPP fibers were achieved. Processing and mechanical draw ratio were evaluated. Moreover, nanofilled iPP fibers appeared to be more prone to further drawing, as derived from both the maximum attainable strength and the maximum attainable drawing, as presented in the interpretation model of mechanical testing.
Multi‐pH QSAR: II. Regression Analysis Sensitive Enough to Determine the Transition‐State pKa of Human Buccal Absorption
Authors: Scherrer Robert A.
Published: March 2011

An analysis of published human buccal absorption data of an acid and a base at six pH values extends multi‐pH QSAR to an extreme: QSAR on a single compound. The compounds analyzed are 4‐n‐hexylphenylacetic acid and propranolol. This analysis might be considered as much an analysis of the model as the compound, itself. Ionizable compounds undergo a pKa change in the process of absorption. Multi‐pH QSAR allows determination of the pKa of the presumed rate‐limiting step for absorption, which we label the transition‐state pKa (pKaTS). Comparison of the pKaTS with the corresponding aqueous and membrane pKa values provides the extent of molecular penetration at the transition state. It is 49 % of the path length for the arylacetic acid and 73 % for propranolol.
Constrained maximum likelihood estimation of the diffusion kurtosis tensor using a Rician noise model
Authors: Veraart Jelle , Van Hecke Wim , Sijbers Jan
Published: March 2011

A computational framework to obtain an accurate quantification of the Gaussian and non‐Gaussian component of water molecules' diffusion through brain tissues with diffusion kurtosis imaging, is presented. The diffusion kurtosis imaging model quantifies the kurtosis, the degree of non‐Gaussianity, on a direction dependent basis, constituting a higher order diffusion kurtosis tensor, which is estimated in addition to the well‐known diffusion tensor. To reconcile with the physical phenomenon of molecular diffusion, both tensor estimates should lie within a physically acceptable range. Otherwise, clinically and artificially significant changes in diffusion (kurtosis) parameters might be confounded. To guarantee physical relevance, we here suggest to estimate both diffusional tensors by maximizing the joint likelihood function of all Rician distributed diffusion weighted images given the diffusion kurtosis imaging model while imposing a set of nonlinear constraints. As shown in this study, correctly accounting for the Rician noise structure is necessary to avoid significant overestimation of the kurtosis values. The performance of the constrained estimator was evaluated and compared to more commonly used strategies during simulations. Human brain data were used to emphasize the need for constrained estimators as not imposing the constraints give rise to constraint violations in about 70% of the brain voxels. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Pediatric palliative care provision around the world: A systematic review
Authors: Knapp Caprice , Woodworth Lindsey , Wright Michael , Downing Julia , Drake Ross , Fowler‐Kerry Sue , Hain Richard , Marston Joan
Published: March 2011

Pediatric palliative care is recommended by many organizations. Yet, there is no information available on the progress that has been made in providing this care or the gaps that still exist in provision around the world. We conducted a systematic review to address this gap in knowledge. The systematic review identified 117 peer‐reviewed and non‐peer reviewed resources. Based on this information, each country was assigned a level of provision; 65.6% of countries had no known activities, 18.8% had capacity building activities, 9.9% had localized provision, and 5.7% had provision that was reaching mainstream providers. Understanding the geographic distribution in the level of provision is crucial for policy makers and funders. Pediatr Blood Cancer 2011; 57: 361–368. © 2011 Wiley‐Liss, Inc.
Walking in each other's Shoes: Perspective Taking Mediates Effects of Emotional Intelligence on Relationship Quality
Authors: Schröder–Abé Michela , Schütz Astrid
Published: March 2011

Although theorists have repeatedly emphasized that emotional intelligence should be linked to relationship quality, little empirical research has systematically examined emotional intelligence in romantic relationships using appropriate dyadic designs and analyses. The present research investigated the relationship between emotional intelligence and aspects of relationship quality (satisfaction, closeness and commitment). Study 1 was conducted online with 191 heterosexual couples. We found that a person's perceptions of relationship quality were predicted not only by that person's emotional intelligence, but also by the relationship partner's emotional intelligence. In Study 2, these positive actor and partner effects of emotional intelligence on relationship satisfaction and closeness were replicated in a sample of 80 couples in the laboratory. In this context, couples engaged in a conflict discussion, and perspective taking of the partners was rated by the experimenter. Actor–Partner Interdependence Mediation Model showed that perspective taking mediated the effects of emotional intelligence on relationship quality. The present research confirmed the link between emotional intelligence and relationship quality and sheds light on the processes through which emotional intelligence affects the quality of romantic relationships. Copyright © 2011 John Wiley & Sons, Ltd.
Reproductive Behavior and Personality Traits of the Five Factor Model
Authors: Jokela Markus , Alvergne Alexandra , Pollet Thomas V. , Lummaa Virpi
Published: March 2011

We examined associations between Five Factor Model personality traits and various outcomes of reproductive behavior in a sample of 15 729 women and men from the Wisconsin Longitudinal Study (WLS) and Midlife Development in the United States (MIDUS) survey. Personality and reproductive history was self–reported in adulthood (mean age: 53 years). High extraversion, high openness to experience, and low neuroticism were associated with larger number of children in both sexes, while high agreeableness and low conscientiousness correlated with larger offspring number in women only. These associations were independent of marital status. There were also more specific associations between personality and timing of childbearing. The findings demonstrate that personality traits of the Five Factor Model are systematically associated with multiple reproductive outcomes. Copyright © 2011 John Wiley & Sons, Ltd.
How to Administer the Initial Preference Task
Authors: Stieger Stefan , Voracek Martin , Formann Anton K.
Published: March 2011

Individuals like their name letters more than non–name letters. This effect has been termed the Name Letter Effect (NLE) and is widely exploited to measure implicit (i.e. automatic, unconscious) self–esteem, predominantly by means of the Initial Preference Task (IPT). Methodological research on how to best administer the IPT is, however, scarce. In order to bridge this gap, the present paper assessed the advantages and disadvantages of different types of IPT administrations with two meta–analyses ( k = 49; N = 11,514) and a follow–up experiment ( N = 449). As a result, a new type of administration is recommended which (1) treats the effects of the first and the last name initials separately, (2) uses a duplicate administration for reliability reasons, (3) uses the likability as well as the attractiveness item wording and (4) exploits not only letters but also numbers (i.e. birthday number effect) to measure implicit self–esteem. Copyright © 2011 John Wiley & Sons, Ltd.
Hypermaturity and Immaturity of Personality Profiles in Adolescents
Authors: Klimstra Theo A. , Hale William W. , Raaijmakers Quinten A. W. , Meeus Wim H. J.
Published: March 2011

Five–year longitudinal data on a cohort of early to middle adolescents ( N = 923) and a cohort of middle to late adolescents ( N = 390) were used to examine the correlates of hypermaturity (i.e. 12–year–olds with a personality profile resembling the profile of an average 20–year–old) and immaturity (i.e. 20–year–olds with a personality profile resembling the profile of an average 12–year–old) of personality. Analyses revealed that girls with high levels of hypermaturity exhibited high levels of internalizing problem behaviour and conflict with parents, while hypermaturity in boys was only associated with internalizing problems. Immature girls had low levels of anxiety and high levels of minor delinquency, whereas immature boys reported low levels of anxiety and high levels of physical maturity. These findings suggest that off–time personality development is an interesting concept deserving further exploration. Copyright © 2011 John Wiley & Sons, Ltd.
Embedding multiple site‐specific functionalities into polymer chains via nitrone‐mediated radical coupling reactions
Authors: Wong Edgar H. H. , Stenzel Martina H. , Junker Tanja , Barner‐Kowollik Christopher
Published: March 2011

A facile method to generate polymer materials with embedded functional groups at known and precise positions along the polymer backbone is described. In the presented approach, well‐defined bifunctional poly(isobornyl acrylate)s preformed via atom transfer radical polymerization (ATRP) containing α,ω‐bromo end groups are reactivated and subsequently coupled in a stepwise manner via the nitrone‐mediated radical coupling (NMRC) technique. The generated polymers contain on average four nitrone moieties at evenly spaced locations. The number of embedded functionalities, and thus, the size of the polymer is limited by disproportionation reactions occurring during the nitroxide termination sequence. Using the nitrone as a functional carrier, secondary functionalities can be incorporated into the polymer with ease. To exemplify such an approach, an alkyne‐functionalized nitrone is used to construct a multisegment structure via NMRC reactions followed by postmodification of the obtained polymers with 3‐mercaptopropionic acid via UV‐induced thiol‐yne reactions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Solution structure and backbone dynamics of the DNA‐binding domain of FOXP1: Insight into its domain swapping and DNA binding
Authors: Chu Yuan‐Ping , Chang Chia‐Hao , Shiu Jia‐Hau , Chang Yao‐Tsung , Chen Chiu‐Yueh , Chuang Woei‐Jer
Published: March 2011

FOXP1 belongs to the P‐subfamily of forkhead transcription factors and contains a conserved forkhead DNA‐binding domain. According to size exclusion chromatography analysis, the forkhead domain of FOXP1 existed as a mixture of monomer and dimer. The dissociation constants of the forkhead domain of wild‐type, C61S, and C61Y mutants of FOXP1 were 27.3, 28.8, and 332.0 μM, respectively. In contrast, FOXP1 A39P mutant formed only a monomer. NMR analysis also showed that FOXP1 C61S and C61Y mutants existed as a mixture. The solution structure of FOXP1 A39P/C61Y mutant was similar to the X‐ray structure of the FOXP2 monomer. Comparison of backbone dynamics of FOXP1 A39P/C61Y and C61Y mutants showed that the residues preceding helix 3, the hinge region, exhibited the largest conformational exchange in FOXP1 monomer. The A39 residue of FOXP1 dimer has a lower order parameter with internal motion on the ps‐ns timescale, suggesting that the dynamics of the hinge region of FOXP1 are important in the formation of the swapped dimer. The analysis also showed that the residues exhibiting the motions on the ps‐ns and μs‐ms timescales were located at the DNA‐binding surface of FOXP1, suggesting the interactions between FOXP1 and DNA may be highly dynamic.
Integration of RF inductors and filters on mesoporous silicon isolation layers
Authors: Billoué Jérôme , Gautier Gaël , Ventura Laurent
Published: March 2011

In this paper, we present electrochemical etching conditions to obtain thick mesoporous silicon electrical insulating layers for RF applications from high resistivity substrates (30–50 Ω cm). We present the realization and the characterization of spiral inductors on thick mesoporous silicon layers. Indeed, PSi layers reduce significantly the resistive and capacitive losses of the substrate, so, quality factor and resonant frequencies are improved for integrated inductors. In complement, we develop the integration of such devices in notch filters and we show the first measurement results on 100 µm thick mesoporous silicon layers.
Matrix‐free mass spectrometric imaging using laser desorption ionisation Fourier transform ion cyclotron resonance mass spectrometry
Authors: Goodwin Richard J. A. , Pitt Andrew R. , Harrison David , Weidt Stefan K. , Langridge‐Smith Pat R. R. , Barrett Michael P. , Logan Mackay C.
Published: March 2011

Mass spectrometry imaging (MSI) is a powerful tool in metabolomics and proteomics for the spatial localization and identification of pharmaceuticals, metabolites, lipids, peptides and proteins in biological tissues. However, sample preparation remains a crucial variable in obtaining the most accurate distributions. Common washing steps used to remove salts, and solvent‐based matrix application, allow analyte spreading to occur. Solvent‐free matrix applications can reduce this risk, but increase the possibility of ionisation bias due to matrix adhesion to tissue sections. We report here the use of matrix‐free MSI using laser desorption ionisation performed on a 12 T Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. We used unprocessed tissue with no post‐processing following thaw‐mounting on matrix‐assisted laser desorption ionisation (MALDI) indium‐tin oxide (ITO) target plates. The identification and distribution of a range of phospholipids in mouse brain and kidney sections are presented and compared with previously published MALDI time‐of‐flight (TOF) MSI distributions. Copyright © 2011 John Wiley & Sons, Ltd.
2H stable isotope analysis of human tooth enamel: a new tool for forensic human provenancing?
Authors: Holobinko A. , Meier‐Augenstein W. , Kemp H. F. , Prowse T. , Ford S. M.
Published: March 2011

Stable isotope analysis of biogenic tissues such as tooth enamel and bone mineral has become a well‐recognised and increasingly important method for determining the provenance of human remains, and it has been used successfully in bio‐archaeological studies as well as forensic investigations. In particular, 18O and 2H stable isotope signatures of bone and hair, respectively, are well‐established proxies of climate (temperature) and source water and are therefore considered as indicators of geographic life trajectories of animals and humans. While the methodology for 2H analysis of human hair, fingernails, and bone collagen is currently used to determine human provenance, i.e. geographic origin and identify possible migration patterns, studies involving the analysis of 2H in tooth enamel appear to be nonexistent in the scientific literature. Ground tooth enamel was analysed by continuous‐flow isotope ratio mass spectrometry (IRMS) coupled on‐line to a high‐temperature conversion elemental analyser (TC/EA). An array of tooth enamel samples from archaeological and modern teeth has been analysed under different experimental conditions, and the results of this proof‐of‐concept study are presented. While no significant differences in 2H abundance were noted as a result of H exchange studies or different sample preparation protocols, no significant differences or trends in measured δ2H‐values were observed either with regard to known differences in geographical provenance. We concluded that the δ2H‐values obtained from tooth enamel could not be used as proxy for a person's geographical origin during adolescence. Copyright © 2011 John Wiley & Sons, Ltd.
Three‐dimensional mass spectral imaging of HeLa‐M cells – sample preparation, data interpretation and visualisation
Authors: Fletcher John S. , Rabbani Sadia , Henderson Alex , Lockyer Nicholas P. , Vickerman John C.
Published: March 2011

Time‐of‐flight secondary ion mass spectrometry (ToFSIMS) is being applied increasingly to the study of biological systems where the chemical specificity of mass spectrometry and the high lateral resolution imaging capabilities can be exploited. Here we report a comparison of two cell sample preparation methods and demonstrate how they influence the outcome of the ToFSIMS analysis for three‐dimensional (3D) imaging of biological cells using our novel buncher‐ToF instrument (J105 3D Chemical Imager) equipped with a C60 primary ion beam. Cells were analysed fixed and freeze‐dried and non‐fixed, frozen‐hydrated. It is concluded that maintaining the cells in a non‐fixed frozen‐hydrated state during the analysis helps reduce chemical redistribution, producing cleaner spectra and improved chemical contrast in both 2D and 3D imaging. Insights into data interpretation are included and we present methods for 3D reconstruction of the data using multivariate analysis techniques. Copyright © 2011 John Wiley & Sons, Ltd.
Mass spectrometric study of bradykinin‐related peptides (BRPs) from the skin secretion of Russian ranid frogs
Authors: Samgina T. Yu. , Gorshkov V. A. , Vorontsov Ye. A. , Artemenko K. A. , Zubarev R. A. , Lebedev A. T.
Published: March 2011

Amphibian skin secretion is known to contain biologically active peptides. Bradykinins and related peptides (BRPs) can be found in these animals, while frogs from the genus Rana are considered to be leaders in the levels and variety of these peptides. A reasonable rationalization of this fact is that bradykinins are efficient defense compounds against predators. Forty‐four various BRPs have been identified in the skin secretions of five ranid frog species (R. ridibunda, R. lessonae, R. esculenta, R. temporaria, R. arvalis) from the Zvenigorod region (Moscow district, Russia). Some of these peptides are already known, but the novel ones constitute a significant portion. An interesting group of novel peptides was isolated from R. lessonae. These are bradykinin analogues bearing a tyrosine residue in the 5th or 8th position. [Arg0,Trp5,Leu8]bradykinin and [Thr6,Leu8]bradykinin that had been isolated from fish and avian species, respectively, were also detected in the frog secretion, supporting the predator defense hypothesis. Furthermore, a novel group of BRPs named 'lessonakinins' was discovered in R. lessonae and R. esculenta. All of them include the [Arg0,Trp5,Leu8]bradykinin sequence and have some structural resemblance to the precursor of this peptide cloned by Chen and coworkers recently. However, the C‐terminal part of the lessonakinins does not match the sequence predicted by Chen, demonstrating possible incompleteness of information obtained by cDNA cloning. Copyright © 2011 John Wiley & Sons, Ltd.
X‐ray photoelectron spectroscopy depth analysis of metal oxides by electrospray droplet impact
Authors: Sakai Yuji , Ninomiya Satoshi , Hiraoka Kenzo
Published: March 2011

The electrospray droplet impact (EDI) method is a newly developed etching method using extremely large charged water cluster ions with masses of several 106 u. This work presents a comparative XPS study of chemical states of the transition metal oxides, TiO2 and Ta2O5, etched by Ar+ and EDI. Selective sputtering of oxygen was observed by Ar+ etching for these samples, but no chemical modification took place by EDI. This finding provided further evidence that EDI has the capability of nonselective etching for both inorganic and organic materials. Copyright © 2011 John Wiley & Sons, Ltd.
Calibration of prior variance in the Bayesian continual reassessment method
Authors: Lee Shing M. , Cheung Ying Kuen
Published: March 2011

The continual reassessment method (CRM) is an adaptive model‐based design used to estimate the maximum tolerated dose in phase I clinical trials. Asymptotically, the method has been shown to select the correct dose given that certain conditions are satisfied. When sample size is small, specifying a reasonable model is important. While an algorithm has been proposed for the calibration of the initial guesses of the probabilities of toxicity, the calibration of the prior distribution of the parameter for the Bayesian CRM has not been addressed. In this paper, we introduce the concept of least informative prior variance for a normal prior distribution. We also propose two systematic approaches to jointly calibrate the prior variance and the initial guesses of the probability of toxicity at each dose. The proposed calibration approaches are compared with existing approaches in the context of two examples via simulations. The new approaches and the previously proposed methods yield very similar results since the latter used appropriate vague priors. However, the new approaches yield a smaller interval of toxicity probabilities in which a neighboring dose may be selected. Copyright © 2011 John Wiley & Sons, Ltd.
Discovering herbal functional groups of traditional Chinese medicine
Authors: He Ping , Deng Ke , Liu Zhihai , Liu Delin , Liu Jun S. , Geng Zhi
Published: March 2011

For the traditional Chinese medicine (TCM), a prescription for a patient often contains several herbs. Some herbs are often used together in prescriptions, and these herbs can be considered as a functional group. In this paper, we propose an approach for discovering herbal functional groups from a large set of prescriptions recorded in TCM books. These functional groups are allowed to overlap with each other. Our approach is validated with a simulation study and applied to a data set containing thousands of TCM prescriptions. Copyright © 2011 John Wiley & Sons, Ltd.
A demand‐driven approach to slicing legacy COBOL systems
Authors: Hajnal Ákos , Forgács István
Published: March 2011

Maintenance of aging legacy COBOL systems is labor‐intensive and is becoming a more and more difficult problem. Program slicing is a potentially useful analysis for aiding different maintenance activities, including program comprehension, reverse engineering, debugging, and testing. Numerous techniques have been proposed in the past decades; however, in interactive contexts, we found none of them suitable for slicing industrial‐scale COBOL systems due to their large space or preprocessing requirements. This paper proposes a novel static program slicing approach, which is based on context‐sensitive token propagation over control flow graphs (CFGs). CFGs require less space compared with program dependence graphs (PDGs) used by other techniques, and the token propagation method computes the necessary information only, on demand. Algorithms are presented for data flow and full slicing to calculate precise program slices. Preliminary application experiences on industrial‐scale COBOL systems are also summarized. Copyright © 2011 John Wiley & Sons, Ltd.
Reliability assessment based on hazard rate model for an embedded OSS porting‐phase
Authors: Tamura Yoshinobu , Yamada Shigeru
Published: March 2011

Embedded Open Source Software (OSS) systems have been gaining a lot of attention in the embedded system area. The successful experience of embedded OSSs include Android, BusyBox, TRON, etc. Also, OSS market will be expanded not only to mobile phone OSS areas but also to other embedded OSS areas in the future. However, the poor handling of quality problem and customer support prohibit the progress of embedded OSS. Also, it is difficult for developers to assess the reliability and portability of embedded OSS on a single‐board computer. A method of software reliability assessment based on flexible hazard rate modeling for the embedded OSS is proposed in this paper. Also, several numerical examples are shown by using actual data. Moreover, this paper compares the proposed model with the conventional hazard rate models by using the comparison criteria of goodness‐of‐fit. Copyright © 2011 John Wiley & Sons, Ltd.
Machine learning, data mining, and computational statistics applications
Authors: Wegman Edward J. , Said Yasmin H. , Scott David W.
Published: March 2011

This article is categorized under:

Applications of Computational Statistics > Organizations and Publications
Existence of weak solutions to the three-dimensional steady compressible Navier–Stokes equations
Authors: Zhou Chunhui , Jiang Song
Published: March 2011

We prove the existence of a spatially periodic weak solution to the steady compressible isentropic Navier–Stokes equations in

\mathbb{R}^{3}

for any specific heat ratio

\gamma > 1

. The proof is based on the weighted estimates of both pressure and kinetic energy for the approximate system which result in some higher integrability of the density, and the method of weak convergence.
Effect of ultrasound on the physical and functional properties of reconstituted whey protein powders
Authors: Zisu Bogdan , Lee Judy , Chandrapala Jayani , Bhaskaracharya Raman , Palmer Martin , Kentish Sandra , Ashokkumar Muthupandian
Published: March 2011

Aqueous solutions of reconstituted whey protein- concentrate (WPC) & isolate (WPI) powders were sonicated at 20 kHz in a batch process for 1–60 min. Sonication at 20 kHz increased the clarity of WPC solutions largely due to the reduction in the size of the suspended insoluble aggregates. The gel strength of these solutions when heated at 80°C for 20 min also increased with sonication, while gelation time and gel syneresis were reduced. These improvements in gel strength were observed across a range of initial pH values, suggesting that the mechanism for gel promotion is different from the well known effects of pH. Examining the microstructure of the whey protein gels indicated a compact network of densely packed whey protein aggregates arising from ultrasound treatment. Comparable changes were not observed with whey protein isolate solutions, which may reflect the absence of larger aggregates in the initial solution or differences in composition.
Is adjustment to retirement an individual responsibility? Socio-contextual conditions and options available to retired persons: the Korean perspective
Authors: YANG YUNJEONG
Published: March 2011

Although the socio-economic and structural contexts of retirement have been the subject of previous research, few studies state explicitly how societal ageism and structural constraints obstruct retired persons' choices or options available in post-retirement life. This study attempts to contribute to the literature of ageing, retirement, and wellbeing in later life in general, by providing real examples of ageism around the time of retirement as structural constraints of old persons. It also illustrates how they consequently reduce the choices of retired persons, and in turn affect their later life. The study draws on data from interviews with 34 retirees aged in their late fifties and sixties in Korea. Within the socio-economic context of ageism around the time of retirement, four options/strategies appear to be available; namely reconciling, complaining and not knowing what to do, finding roles in other activities, and disengaging. Older persons' decisions to continue to work after retirement are often reconciling ones, that is, taken within a context of limited choice and control. Permanent leavers' decisions not to work are also influenced by the limited quality of work available in the labour market. The study concludes by arguing that policies for older persons should take into consideration their diverse expectations and aspirations for their later life, but, at the same time, should remain aware of their constraints within socio-economic contexts.
Poverty Variations among the Elderly: The Roles of Income Security Policies and Family Co-Residence
Authors: Kaida Lisa , Boyd Monica
Published: March 2011

Malgré un déclin rapide depuis les années 1970, la pauvreté parmi les immigrants âgées demeure toujours élevée. Utilisant le recensement canadien de la population en 2006, cet article décrit les différences des taux de pauvreté des vieillards immigrants comparé aux ceux nés au Canada. Les résultats de l’analyse logistique de régression suggèrent qu’une grande partie du haut taux de pauvreté parmi les immigrants âgés est dû au manque, ou à l’insuffisance, d’appui financier du gouvernement. Néanmoins, la pauvreté élevée parmi les immigrants âgés est atténuée par l’aide financière de leurs familles. Cet article conclut en mettant l’emphase sur le rôle que la famille peut jouer pour contrer la pauvreté qui fait face aux vieillards immigrants, et en évaluant deux mécanismes d’intervention du gouvernement qui pourraient améliorer le bien-être économique des immigrants âgés.
Conceptual and Measurement Challenges in Research on Cognitive Reserve
Authors: Jones Richard N. , Manly Jennifer , Glymour M. Maria , Rentz Dorene M. , Jefferson Angela L. , Stern Yaakov
Published: March 2011

Cognitive reserve, broadly conceived, encompasses aspects of brain structure and function that optimize individual performance in the presence of injury or pathology. Reserve is defined as a feature of brain structure and/or function that modifies the relationship between injury or pathology and performance on neuropsychological tasks or clinical outcomes. Reserve is challenging to study for two reasons. The first is: reserve is a hypothetical construct, and direct measures of reserve are not available. Proxy variables and latent variable models are used to attempt to operationalize reserve. The second is:in vivomeasures of neuronal pathology are not widely available. It is challenging to develop and test models involving a risk factor (injury or pathology), a moderator (reserve) and an outcome (performance or clinical status) when neither the risk factor nor the moderator are measured directly. We discuss approaches for quantifying reserve with latent variable models, with emphasis on their application in the analysis of data from observational studies. Increasingly latent variable models are used to generate composites of cognitive reserve based on multiple proxies. We review the theoretical and ontological status of latent variable modeling approaches to cognitive reserve, and suggest research strategies for advancing the field. (JINS, 2011,17, 593–601)
Middle to late Miocene extremely rapid exhumation and thermal reequilibration in the Kung Co rift, southern Tibet
Authors: Lee Jeffrey , Hager Christian , Wallis Simon R. , Stockli Daniel F. , Whitehouse Martin J. , Aoya Mutsuki , Wang Yu
Published: March 2011

The Kung Co rift is an approximately NNW striking, WSW dipping normal fault exposed in southern Tibet and is part of an extensive network of active approximately NS striking normal faults exposed across the Tibetan Plateau. Detailed new and published (U‐Th)/He zircon and apatite thermochronometric data from the footwall of the early Miocene Kung Co granite provide constraints on the middle Miocene to present‐day exhumation history of the footwall to the Kung Co fault. Inverse modeling of thermochronometric data yield age patterns that are interpreted as indicating (1) initiation of normal fault slip at ∼12–13 Ma and rapid exhumation of the footwall between ∼13 and 10 Ma, (2) acceleration of normal fault slip at rates of 21.9–6.9 mm/yr at ∼10 Ma, (3) rapid thermal reequilibration between 10 and 9 Ma, and (4) slow exhumation and/or quiescence from ∼9 Ma to the present day. Hanging glacial valleys in the footwall and fault scarps that cut late Quaternary till and moraine deposits indicate that fault slip continues today. Middle to late Miocene initiation of extension across the Kung Co rift is broadly the same as the documented initiation of EW extension across the south central Tibetan Plateau. Eastward flow of middle or lower crust from beneath Tibet accommodated by northward underthrusting of Indian crust beneath Tibet provides a plausible explanation for the onset of EW extension across the Tibetan Plateau.
Proposed Budget for U.S. Geological Survey: A Mixed Bag of Increases and Cuts
Authors: Showstack Randy
Published: March 2011

Under the Obama administration's proposed fiscal year (FY) 2012 budget, the U.S. Geological Survey (USGS) would receive $1.1 billion, a scant $6.1 million more than the 2010 enacted budget. Within the agency, which is part of the Department of the Interior (DOI), some key initiatives slated for new or increased funding include the National Land Imaging Program, the USGS portion of the America's Great Outdoors Initiative, and DOI Climate Science Centers. However, the request also includes $89.1 million in program reductions and the elimination of some programs. With Congress currently considering a budget continuing resolution to fund the federal government through the end of the current fiscal year, 2011, USGS faces possible additional cuts.
Donald R. Johnson Receives 2010 Excellence in Geophysical Education Award
Authors: Ruzek Martin , Johnson Donald R.
Published: March 2011

Donald R. Johnson received the Excellence in Geophysical Education Award at the 2010 AGU Fall Meeting Honors Ceremony, held on 15 December 2010 in San Francisco, Calif. The award honors “a sustained commitment to excellence in geophysical education by a team, individual, or group.”