bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of spaceborne lidar for the evaluation of thin cirrus contamination and screening in the Aqua MODIS Collection 5 aerosol products
Authors: Huang Jingfeng , Hsu N. Christina , Tsay Si‐Chee , Liu Zhaoyan , Jeong Myeong‐Jae , Hansell Richard A. , Lee Jaehwa
Published: May 2013

Cloud contamination from subvisual thin cirrus clouds is still a challenging issue for operational satellite aerosol retrievals. In the A‐Train constellation, concurrent high‐sensitivity cirrus observations from the Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) provide us with an unprecedented opportunity to examine the susceptibility of the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol retrievals to thin cirrus contamination and to evaluate the robustness of various cirrus screening techniques. Quantitative evaluations indicate that the current cirrus screening schemes in the MODIS Dark Target and Deep Blue Collection 5 aerosol retrievals can effectively remove most cirrus signals while some residual thin cirrus signals still exist with strong spatial and seasonal variability. Results also show significant linkage between thin cirrus occurrence frequency and the susceptibility of aerosol retrievals to thin cirrus contamination. Using the CALIPSO cirrus observations as a reference, we also examined the effectiveness and robustness of eight MODIS‐derived cirrus screening parameters. These parameters include apparent reflectance at 1.38 µm (R1.38), cirrus reflectance at 0.66 µm (CR0.66), CR0.66 cirrus flag (CF), reflectance ratio between 1.38 µm and 0.66 µm (RR1.38/0.66), reflectance ratio between 1.38 µm and 1.24 µm (RR1.38/1.24), brightness temperature difference between 8.6 µm and 11 µm (BTD8.6–11), brightness temperature difference between 11 µm and 12 µm (BTD11–12), and cloud phase infrared approach (CPIR). Among these parameters, RR1.38/0.66 achieves the best overall performance, followed by the BTD11–12. Results from several test cases suggest that the cirrus screening schemes in the operational MODIS aerosol retrieval algorithms can be further improved to reduce thin cirrus contamination.
MR characterization of hepatic storage iron in transfusional iron overload
Authors: Tang Haiying , Jensen Jens H. , Sammet Christina L. , Sheth Sujit , Swaminathan Srirama V. , Hultman Kristi , Kim Daniel , Wu Ed X. , Brown Truman R. , Brittenham Gary M.
Published: May 2013

Purpose

To quantify the two principal forms of hepatic storage iron, diffuse, soluble iron (primarily ferritin), and aggregated, insoluble iron (primarily hemosiderin) using a new MRI method in patients with transfusional iron overload.

Materials and Methods

Six healthy volunteers and 20 patients with transfusion‐dependent thalassemia syndromes and iron overload were examined. Ferritin‐ and hemosiderin‐like iron were determined based on the measurement of two distinct relaxation parameters: the “reduced” transverse relaxation rate, RR2, and the “aggregation index,” A, using three sets of Carr‐Purcell‐Meiboom‐Gill (CPMG) datasets with different interecho spacings. Agarose phantoms, simulating the relaxation and susceptibility properties of tissue with different concentrations of dispersed (ferritin‐like) and aggregated (hemosiderin‐like) iron, were used for validation.

Results

Both phantom and in vivo human data confirmed that transverse relaxation components associated with the dispersed and aggregated iron could be separated using the two‐parameter (RR2, A) method. The MRI‐determined total hepatic storage iron was highly correlated (r = 0.95) with measurements derived from biopsy or biosusceptometry. As total hepatic storage iron increased, the proportion stored as aggregated iron became greater.

Conclusion

This method provides a new means for noninvasive MRI determination of the partition of hepatic storage iron between ferritin and hemosiderin in iron overload disorders. J. Magn. Reson. Imaging 2014;39:307–316. © 2013 Wiley Periodicals, Inc.
Three‐dimensional functional MRI with parallel acceleration: Balanced SSFP versus PRESTO
Authors: Vallée Emilie , Håberg Asta K. , Kristoffersen Anders
Published: May 2013

Purpose

To compare the sensitivity and specificity of three‐dimensional (3D) principles of echo shifting using a train of observations (PRESTO) and passband balanced steady‐state free precession (SSFP) functional MRI (fMRI) sequences combined with integrated parallel acquisition techniques (iPAT) at 3 Tesla (T).

Materials and Methods

The 3D fMRI was performed using PRESTO and passband balanced SSFP with 3 mm and 1.9 mm isotropic voxels combined with iPAT, while volunteers underwent visual stimulation. From whole‐brain activation maps and predefined regions of interest in the visual cortex, Z‐score distributions, percentage of fMRI signal change, and the fMRI signals' temporal profile were compared between the sequences for the two spatial resolutions to estimate sensitivity and specificity.

Results

For PRESTO, the Z‐score distributions had higher mean and maximum Z‐values for both resolutions than for SSFP, and the activated voxels were located to the visual cortex with high sensitivity. For SSFP, the activation was more scattered, and voxels with the highest sensitivity were found in the draining veins. The good functional contrast in PRESTO allowed for separation of voxels with early (<5 s) and late (>5 s) signal change; thus, the signal from larger draining veins could be removed. The ensuing PRESTO activation maps represent the early fMRI signal, probably more closely related to neuronal activity.

Conclusion

The 3D fMRI PRESTO sequence demonstrated better sensitivity and specificity than SSFP. J. Magn. Reson. Imaging 2014;39:656–664. © 2013 Wiley Periodicals, Inc.
Short‐term effects of a standardized glucose load on region‐specific aortic pulse wave velocity assessed by MRI
Authors: Jonker Jacqueline T. , Tjeerdema Nathanja , Hensen Liselotte C.R. , Lamb Hildo J. , Romijn Johannes A. , Smit Johannes W.A. , Westenberg Jos J.M. , de Roos Albert
Published: May 2013

Purpose

To assess the short‐term effects of a standardized oral glucose load on regional aortic pulse wave velocity (PWV) using two‐directional in‐plane velocity encoded MRI.

Materials and Methods

A randomized, controlled intervention was performed in 16 male subjects (mean ± standard deviation: age: 59 ± 7 years, body mass index: 28 ± 3 kg/m2) with impaired fasting glucose. The intervention consisted of an oral glucose load (75 grams of carbohydrates in 300 mL water) at 1 study day and water (300 mL) at the other study day. PWV was measured using multislice two‐directional in‐plane velocity‐encoded MRI.

Results

PWV in the proximal aorta at 1 h post‐glucose load decreased compared with PWV 1‐h post‐water (delta PWV: −1.0 ± 2.6 m/s versus 0.6 ± 2.0 m/s, P = 0.02). Eight responding subjects showed a significant decrease in PWV of the proximal aorta after the glucose load and had a decreased waist circumference (P = 0.037) compared with nonresponders, being one of the major criteria of the metabolic syndrome. There was no significant change in PWV of the distal aorta at 1 h post‐load comparing both intervention groups.

Conclusion

A standardized oral glucose load induces a decrease of the proximal, but not of the distal, aortic PWV. Regional response of aortic PWV may be associated with features of the metabolic syndrome. J. Magn. Reson. Imaging 2014;39:717–721. © 2013 Wiley Periodicals, Inc.
Effect of echo‐sampling strategy on the accuracy of out‐of‐phase and in‐phase multiecho gradient‐Echo MRI hepatic fat fraction estimation
Authors: Levin Yakir S. , Yokoo Takeshi , Wolfson Tanya , Gamst Anthony C. , Collins Julie , Achmad Emil A. , Hamilton Gavin , Middleton Michael S. , Loomba Rohit , Sirlin Claude B.
Published: May 2013

Purpose

To assess the effect of echo‐sampling strategy on the accuracy of out‐of‐phase (OP) and in‐phase (IP) multiecho gradient‐echo magnetic resonance imaging (MRI) hepatic fat fraction (FF) estimation, using MR spectroscopy (MRS) proton density FF (PDFF) as a reference standard.

Materials and Methods

In this Institutional Review Board (IRB)‐approved, Health Insurance Portability and Accountability Act (HIPAA)‐compliant prospective study, 84 subjects underwent proton MRS and non‐T1‐weighted gradient‐echo imaging of the liver at 3T. Imaging data were collected at 16 nominally OP and IP echo times (TEs). MRI‐FF was estimated while varying two echo‐sampling parameters (number of consecutive echoes, starting echo number). For each combination of these parameters, MRI‐FF estimation accuracy was assessed with slope, intercept, average bias, and R2 from a linear regression of MRS‐PDFF on MRI‐FF. The relationship between accuracy metrics and echo‐sampling parameters was assessed by Spearman rank correlation.

Results

For FF calculations using 3–16 echoes and a starting echo number of 1, the intercept ranged from 0.0046 to 0.0124, slope from 0.941 to 0.96, average bias from 0.0034 to 0.0078, and R2 from 0.968 to 0.976. All four accuracy metrics were the best with the 3‐ and 4‐echo calculations and worsened progressively with an increasing number of echoes. For a given number of echoes, there was an overall trend toward decreasing accuracy as starting echo number increased. Spearman correlation coefficients between starting echo number and intercept, slope, average bias, and R2 were 0.911, −0.64, −0.889, and −0.954, respectively, indicating progressive loss of accuracy in each case.

Conclusion

Multiecho OP and IP imaging provided high FF estimation accuracy. Accuracy was highest using the earliest 3 or 4 echoes. Incorporation of additional echoes or delaying the starting echo number progressively reduced accuracy. J. Magn. Reson. Imaging 2014;39:567–575. © 2013 Wiley Periodicals, Inc.
NMR relaxation in systems with magnetic nanoparticles: A temperature study
Authors: Issa Bashar , Obaidat Ihab M. , Hejasee Rola H. , Qadri Shahnaz , Haik Yousef
Published: May 2013

Purpose

To measure and model nuclear magnetic resonance (NMR) relaxation enhancement due to the presence of gadolinium (Gd)‐substituted Zn‐Mn ferrite magnetic nanoparticles (MNP) at different temperatures.

Materials and Methods

Relaxation rates were measured at 1.5 T using fast spin echo (FSE) sequences in samples of agarose gel doped with uncoated and polyethylene glycol (PEG)‐coated Mn0.5Zn0.5Gd0.02Fe1.98O4 nanoparticles over the temperature range 8–58°C. Physical characterization of the MNPs synthesized using chemical coprecipitation included scanning (SEM) and transmission (TEM) electron microscopy, inductively coupled plasma (ICP), dynamic light scattering (DLS), and magnetometry.

Results

Relaxivity (in s−1 mM−1 Fe) for the uncoated and coated particles, respectively, increased as follows: from 2.5 to 3.2 and 0.4 to 0.7 for T1, while for T2 it increased from 162.3 to 253.7 and 59.7 to 82.2 over the temperature range 8–58°C. T2 data were fitted to the echo limited motional regime using one fitting parameter that reflects the degree of agglomeration of particles into a cluster. This parameter was found to increase linearly with temperature and was larger for the PEG‐coated particles than the uncoated ones.

Conclusion

The increase of 1/T2 with temperature is modeled successfully using echo limited motional regime where both diffusion of the protons and nanoparticle cluster size increase with temperature. Both transverse and longitudinal relaxation efficiencies are reduced by PEG coating at all temperatures. If prediction of relaxation rates under different particle concentrations and operating temperatures is possible then the use of MNP in temperature monitoring and hyperthermia applications may be achieved. J. Magn. Reson. Imaging 2014;39:648–655. © 2013 Wiley Periodicals, Inc.
Quantitative mapping of glycoprotein micro‐heterogeneity and macro‐heterogeneity: an evaluation of mass spectrometry signal strengths using synthetic peptides and glycopeptides
Authors: Stavenhagen Kathrin , Hinneburg Hannes , Thaysen‐Andersen Morten , Hartmann Laura , Silva Daniel Varón , Fuchser Jens , Kaspar Stephanie , Rapp Erdmann , Seeberger Peter H. , Kolarich Daniel
Published: May 2013

Mass spectrometry (MS) is used to quantify the relative distribution of glycans attached to particular protein glycosylation sites (micro‐heterogeneity) and evaluate the molar site occupancy (macro‐heterogeneity) in glycoproteomics. However, the accuracy of MS for such quantitative measurements remains to be clarified. As a key step towards this goal, a panel of related tryptic peptides with and without complex, biantennary, disialylated N‐glycans was chemically synthesised by solid‐phase peptide synthesis. Peptides mimicking those resulting from enzymatic deglycosylation using PNGase F/A and endo D/F/H were synthetically produced, carrying aspartic acid and N‐acetylglucosamine‐linked asparagine residues, respectively, at the glycosylation site. The MS ionisation/detection strengths of these pure, well‐defined and quantified compounds were investigated using various MS ionisation techniques and mass analysers (ESI‐IT, ESI‐Q‐TOF, MALDI‐TOF, ESI/MALDI‐FT‐ICR‐MS). Depending on the ion source/mass analyser, glycopeptides carrying complex‐type N‐glycans exhibited clearly lower signal strengths (10–50% of an unglycosylated peptide) when equimolar amounts were analysed. Less ionisation/detection bias was observed when the glycopeptides were analysed by nano‐ESI and medium‐pressure MALDI. The position of the glycosylation site within the tryptic peptides also influenced the signal response, in particular if detected as singly or doubly charged signals. This is the first study to systematically and quantitatively address and determine MS glycopeptide ionisation/detection strengths to evaluate glycoprotein micro‐heterogeneity and macro‐heterogeneity by label‐free approaches. These data form a much needed knowledge base for accurate quantitative glycoproteomics. Copyright © 2013 John Wiley & Sons, Ltd.
Resolving double disulfide bond patterns in SNAP25B using liquid chromatography–ion trap mass spectrometry
Authors: Ogawa Nozomi , Taylor Ryan M. , Woodbury Dixon J. , Prince John T.
Published: May 2013

Complex disulfide bond patterns in synaptosomal‐associated protein of 25 kD B (SNAP25B) are thought to regulate neurotransmitter release in response to oxidative stress. However, the steric feasibility of each possible disulfide pattern in SNAP25B has not been assessed. To assess the steric feasibility of hypothesized closely spaced complex disulfide patterning in SNAP25B and also the feasibility of identifying complex disulfide bond patterns with MS, we have developed a novel probabilistic analysis to unambiguously resolve complex double disulfide bond patterns by using an ion trap mass spectrometer. We analyzed fragmentation patterns of singly linked peptides to determine likely fragmentation events in an ion trap mass spectrometer and observed double and single backbone cleavage along with heterolytic cleavage of the disulfide bond. We modeled these same events in the doubly disulfide linked SNAP25B peptide and used a cumulative hypergeometric distribution with top–down scoring to both identify and differentiate these bonding patterns. Because of the presence of unique MS/MS peaks, two of the bonding patterns were directly identified. The third was assigned on the basis of full chromatographic separation and confirmed by modeling triple breakage fragments. In total, this work demonstrates the feasibility – and also limitations – of identification of complex intradisulfide patterns by using ion trap‐based collision‐induced dissociation‐based fragmentation methods. Copyright © 2013 John Wiley & Sons, Ltd.
Direct desorption/ionization of analytes by microwave plasma torch for ambient mass spectrometric analysis
Authors: Zhang Tiqiang , Zhou Wei , Jin Wei , Zhou Jianguang , Handberg Eric , Zhu Zhiqiang , Chen Huanwen , Jin Qinhan
Published: May 2013

Ambient ionization is the new revolution in mass spectrometry (MS). A microwave plasma produced by a microwave plasma torch (MPT) at atmospheric pressure was directly used for ambient mass spectrometric analysis. H3O+ and NH4+ and their water clusters from the background are formed and create protonated molecules and ammoniated molecules of the analytes. In the full‐scan mass spectra, both the quasi‐molecular ions of the analytes and their characteristic ionic fragments are obtained and provide evidence of the analyte. The successful detection of active compounds in both medicine and garlic proves that MPT has the efficient desorption/ionization capability to analyze solid samples. The obtained decay curve of nicotine in exhaled breath indicates that MPT‐MS is a useful tool for monitoring gas samples in real time. These results showed that the MPT, with the advantages of stable plasma, minimal optimization, easy, solvent‐free operation, and no pretreatment, is another potential technique for ambient MS. Copyright © 2013 John Wiley & Sons, Ltd.
Efficiency of the dry–wet method for the MALDI‐MSI analysis of latent fingermarks
Authors: Ferguson Leesa S , Creasey Stuart , Wolstenholme Rosalind , Clench Malcolm R , Francese Simona
Published: May 2013

Matrix‐assisted laser desorption/ionisation mass spectrometry imaging (MALDI‐MSI) has proven to be a powerful analytical tool to investigate problems in several fields of life science. A novel application is in the field of forensics, particularly in the analysis of latent fingermarks. This technology enables images of the fingermark ridge detail and additional intelligence to be simultaneously obtained. Although several methods are available to deposit the MALDI matrix, to make the technology forensically operational, another deposition approach was devised and reported, namely the ‘dry–wet’ method. In the present study, the efficiency of the dry–wet method was evaluated and compared with the conventional spray coat methodology. Results indicate that the dry–wet method is superior for all the donors' typologies in terms of ion signal intensity and clarity of the ridge details. To underpin the reasons of this efficiency, scanning electron microscopy analyses were carried out in parallel to MALDI‐MSI experiments using matrices of different particle size. Results have confirmed that the particle size plays an important role in the efficiency of the method as higher quality images and higher intensity spectra are produced as the matrix particle size decreases. Copyright © 2013 John Wiley & Sons, Ltd.
Anthranilate degradation by a cold‐adapted Pseudomonas sp.
Authors: Kim Dockyu , Yoo Miyoun , Kim Eungbin , Hong Soon Gyu
Published: May 2013

An alpine soil bacterium Pseudomonas sp. strain PAMC 25931 was characterized as eurypsychrophilic (both psychrophilic and mesotolerant) with a broad temperature range of 5–30 °C both for anthranilate (2‐aminobenzoate) degradation and concomitant cell growth. Two degradative gene clusters (antABC and catBCA) were detected from a fosmid clone in the PAMC 25931 genomic library; each cluster was confirmed to be specifically induced by anthranilate. When expressed in Escherichia coli, the recombinant AntABC (anthranilate 1,2‐dioxygenase, AntDO) converted anthranilate into catechol, exhibiting strict specificity toward anthranilate. Recombinant CatA (catechol 1,2‐dioxygenase, C12O) from the organism was active over a broad temperature range (5–37 °C). However, CatA rapidly lost the enzyme activity when incubated at above 25 °C. For example, 1 h‐preincubation at 37 °C resulted in 100% loss of enzyme activity, while a counterpart from mesophilic Pseudomonas putida mt‐2 did not show any negative effect on the initial enzyme activity. These results suggest that CatA is a new cold‐adapted thermolabile enzyme, which might be a product through the adaptation process of PAMC 25931 to naturally cold environments and contribute to its ability to grow on anthranilate there.
Assessing factors related to the pharmacologic management of laryngeal diseases and disorders
Authors: Cohen Seth M. , Kim Jaewhan , Roy Nelson , Courey Mark
Published: May 2013

Objectives/Hypothesis

To examine how age, gender, comorbidity, geography, provider type, and laryngeal pathology influence the use of pharmacological treatment in managing patients with laryngeal disorders.

Study Design

Retrospective analysis of data from a large, nationally representative, administrative, US claims database.

Methods

Patients with a laryngeal disorder based on International Classification of Diseases, Ninth Revision, Clinical Modification codes from January 1, 2004 to December 31, 2008, seen as an outpatient by a primary care physician (PCP), otolaryngologist, or both and continuously enrolled for 12 months were included. Data regarding pharmacy claims, age, gender, geographic location, comorbid conditions, provider type, and laryngeal diagnosis were collected. To identify factors that influenced whether a patient received a medication or not, a logistic regression was performed.

Results

Of almost 55 million individuals in the database, 258,705 had a laryngeal diagnosis 12 months post‐index date follow‐up and an outpatient encounter with a PCP, otolaryngologist, or both. A total of 135,973 (52.6%) unique patients, mean age 47.4 years (22.2 standard deviation [SD]), with 61.9% female, received a medication, and 122,732 (47.4%), mean age 47.4 years (19.8 SD), with 65.8% female, did not. Higher odds ratios for medication treatment were associated with PCPs versus otolaryngologists, acute laryngitis, the South region, and patients with comorbid conditions. Variable prescription patterns were also observed for age and gender.

Conclusions

Multiple factors are associated with the use of medical treatment for laryngeal disorders.

Level of Evidence

2b. Laryngoscope, 2013
Health care practice patterns for balance disorders in the elderly
Authors: Roberts Daniel S. , Lin Harrison W. , Bhattacharyya Neil
Published: May 2013

Objectives/Hypothesis

Characterize health care practice patterns for balance disorders in the elderly.

Study Design

Cross‐sectional analysis of national health care survey.

Methods

Balance disorder cases in patients aged ≥65 years were extracted from the 2008 National Health Interview Survey. Records were analyzed for health professionals seen, diagnostic testing ordered, diagnoses given, and treatments offered. Relationships between diagnostic success, imaging studies, and specialty providers seen were compared.

Results

Among 7.02 ± 0.22 million elderly persons reporting a balance problem, 50.0% (3.44 ± 0.16 million) saw a health professional, and 35.8% saw ≥3 providers; 59.6% of elderly patients reported a diagnosed cause for the balance problem. The most common causes were medication side effects (11.3%), inner ear infection (11.0%), heart disease (8.6%), and loose ear crystals (7.9%). Imaging studies had been obtained in 56.7% (2.00 ± 0.11 million cases). Among 24.3% of patients receiving some form of treatment, 61.7% had been taking prescription medication, most commonly diuretic agents (36.5%), anxiolytic agents (25.1%), and meclizine (21.4%). Seeing an otolaryngologist or neurologist was associated with a higher but similar rate of diagnostic imaging studies (70.1%, P = .029 and 78.5%, P < .001). However, obtaining an imaging study was not associated with a diagnosed cause of the balance disorder (61.5% with imaging vs. 56.9% without, P = .265).

Conclusions

Despite a high prevalence of balance problems in the elderly, a significant proportion do not come to a clear diagnosis. There is a noteworthy rate of prescription medication utilization in this population. Given an increasingly aging population, attention needs to be given to balance problems in the elderly to optimize diagnosis and health care utilization.

Level of Evidence

2b Laryngoscope, 123:2539–2543, 2013
Conducting Poly(N‐propylaniline) Nanoparticles for Hydrogen Sulfide Gas Detection
Authors: Chabukswar Vasant V. , Bhavsar Sanjay V. , Horne Amit S. , Handore Kalpana , Gaikwad Vishwas B. , Mohite Kakasaheb C.
Published: May 2013

We report a sensitive, selective, and fast responding room temperature chemiresistive sensor for hydrogen sulfide detection and quantification using poly(N‐propylaniline) (PNPA). This sensor shows an excellent wide range of detection with very good selectivity and reproducibility. Organic acid and HCl doped poly(N‐propylaniline) PNPA were synthesized by chemical oxidative polymerization. It was found that the polymer synthesized using DL‐(±)‐Tartaric acid is formed in conducting emeraldine oxidation state and displayed higher doping level and crystallinity than HCl doped poly‐(N‐propylaniline). The polymers were characterized by techniques such as UV‐Visible and FTIR spectroscopy, XRD, SEM and conductivity measurement. The synthesized materials were tested as sensors for acids, bases and organic vapors etc. and categorized. Comparison of the responses of these two polymers reveals that the tartaric acid doped polymer exhibits higher sensitivity and reversibility. The result is discussed with reference to HCl doped and DL‐(±)‐Tartaric acid doped poly(N‐propylaniline). The poly(N‐propyl)aniline pellets were used as sensor by measuring change in resistance before and after exposure to analyte gas. On exposure to H2S gas (10 to 1000 ppm in air) at room temperature, it was found that the PNPA film resistance increases, while that of the PNPA pellet decreases from the respective unexposed value. These changes on removal of H2S gas are reversible in nature, and the polymer PNPA showed good sensitivity with relatively faster response/recovery time. The XRD of PNPA is found to exhibit partial crystallinity as observed from the presence of several peaks at 2θ values of 18 to 41°. The SEM figure indicates that the PNPA/TA consist of coral‐like granular particulates with diameter in the range of 50 to 100 nm.
Nanofibrillar Polymer‐Polymer Composites: Effect of Reinforcement Orientation on the Mechanical Properties
Authors: McCardle Ryan , Fakirov Stoyko , Bhattacharyya Debes
Published: May 2013

In‐situ poly (ethylene terephthalate) (PET) nanofibrils were created by drawing of melt blended polypropylene and PET. The drawn blend was used to prepare polymer‐polymer nanofibrillar composites (NFCs), in order to compare the effect of different fibril orientations on the mechanical properties. The resulting composites showed excellent improvements in stiffness of 116% vs. the isotropic PP matrix for uniaxial NFCs, with the highest recorded modulus of 4.16 GPa for a uniaxial NFC sample, and 3.41 GPa for a crossply sample. Scanning electron microscopy observations confirmed that the nanofibrillar structure and excellent alignment was maintained. Comparisons were also drawn between the composites created in this study, and previous work on microfibrillar composites.
Influence of Temperature and Type of Solvents on the Microdomain Orientation ofPS‐b‐P2VPUltrathin Films by Solvent Annealing
Authors: Shamsudin Siti Aisyah B. , Sakaguchi Go , Takenaka Mikihito , Hasegawa Hirokazu
Published: May 2013

The effect of temperature and type of solvent on the microdomain orientation during solvent‐annealing of block copolymer ultrathin films on silicon substrates was investigated using asymmetric polystyrene‐block‐poly(2‐vinylpyridine) (PS‐b‐P2VP) diblock copolymer. When the solvent‐annealing was performed with THF at 20°C, the ultrathin film exhibited a mixed orientation of cylinders parallel and perpendicular to the substrate while at 25°C only parallel cylinders were observed by AFM. The solvent annealing with acetone gave a dot pattern at 20°C and a line pattern at 25°C. On the other hand, in the case of solvent‐annealing with toluene perpendicular cylinders were observed at 25°C while at 20°C the morphology was not clear. The orientation and morphology of microdomains as well as the kinetics in PS‐b‐P2VP ultrathin films on solvent‐annealing is significantly affected by temperature and type of solvent. By controlling temperature and selecting the solvent, perpendicular cylinders can be formed predominantly on the substrates.
Influence of test method used to evaluate resistance of C‐Mn steel to hydrogen induced cracking
Authors: Jonšta P. , Matocha K. , Jonšta Z. , Koštial P. , Jancíková Z.
Published: May 2013

The presented paper deals with a comparison of test methods for evaluating the resistance of API grade X65 steel to hydrogen induced cracking (HIC). It concerned particularly the ultrasonic immersion method using an AGFA non‐destructive testing device by Krautkrämer and metallographic evaluation of the results of ultrasonic tests according to the directive NACE TM 0284. Comparison of test methods was made on the basis of established parameters of cracks, i. e. crack length ratio (CLR), crack thickness ratio (CTR) and crack sensitivity ratio (CSR). The determination of parameters in case of ultrasonic examination was performed using the pulse reflection method. Metallographic evaluations were performed always at hundred‐fold magnification on a light microscope ZEISS NEOPHOT 32. The obtained results showed that all the test methods used had very small differences between the investigated parameters.
Theoretical approach to a better understanding of gelation in the framework of petroleum industry: role played by different parameters
Authors: Maroto‐Centeno J. A. , Pérez‐Gutiérrez T. , Quesada‐Pérez M.
Published: May 2013

Gelation due to the precipitation of paraffins in petroleum oils is a billion dollar problem in the petroleum industry. The most widely known example in this field is the gelation of crude oil during transportation through sub‐sea pipelines, which in some cases has caused important remediation cost of pipelines blockages. In the case of lubricant oils, gelation is a latent problem from the massive failure in automotive engines that took place in North America during the winter of 1980‐81. In this framework, this work uses a recently developed theoretical survey which has shed light on the physical meaning of the gelation index, that is, the main parameter involved in test ASTM D 5133. This test is commonly used in the petroleum industry for the evaluation of gelation tendency of engine oils at low temperatures. This work analyzes the role played by different parameters (and particularly the induction period and supersaturation ratio) in the theoretical evaluation of the gelation index. In spite of the simplifications used in the theory a qualitative agreement is found when comparing with experimental data, which opens the possibility (after necessary refinements) of a fully predictive theory for nucleation which would be very useful for the petroleum industry.
Equilibrium and dynamic studies for adsorption of boron on calcium alginate gel beads using principal component analysis (PCA) and partial least squares (PLS)
Authors: Ruiz M. , Roset L. , Demey H. , Castro S. , Sastre A. M. , Pérez J. J.
Published: May 2013

In this paper, boron removal from aqueous solutions by adsorption on calcium alginate gel beads was investigated. Based on the batch tests, calcium alginate gel beads demonstrated a good capacity of adsorption; the maximum capacity obtained was 121 mg/g at pH 6. The aim of this paper is the study of analytical tools for extracting more analytical information from a few experiments. Principal component analysis (PCA) was employed to perform a comparative analysis between different isotherms obtained by varying the percentage of alginate on the adsorbent beads. The calculated fraction of the cumulative sum of squares for all the components (R2X(cum)) and the predictive reliability model based on the value of the correlation coefficient of cross validation (Q2 (cum)) obtained were 0.9639 and 0.8523, respectively. Dynamic system study using 20 different columns was carried out. Partial least squares (PLS) modeling are applied to characterize the effect of the experimental variables on the adsorption process. Some of the descriptors studied were the initial boron concentration (Co), adsorbent mass (m), pH, column diameter (dc), column depth (Z) and superficial flow velocity (U0). Experimental adsorptions were compared against predicted adsorptions and a correlation coefficient (r2) of 0.9927 was obtained.
On a numerical model for static and dynamic analysis of in‐plane masonry infilled steel frames
Authors: Radnić J. , Baloević G. , Matešan D. , Smilović M.
Published: May 2013

A numerical model is presented for both static and dynamic analysis of planar masonry‐infilled steel frames, which are loaded only in their plane. The model can simulate all main nonlinear effects of the frame‐infill‐foundation‐soil system. With this model, bare steel and concrete frame structures, masonry structures, as well as masonry‐infilled steel and concrete frame structures can be analysed. Verification of this model was performed on two experimental tests. In example 1 a masonry‐infilled steel frame under static cyclic load and in example 2 a masonry‐infilled steel frame under dynamic load were analysed. The obtained numerical results agree well with experimental results.
Anti–N‐methyl‐D‐aspartate‐glutamic‐receptor encephalitis presenting as paroxysmal exercise‐induced foot weakness
Authors: Labate Angelo , Quattrone Aldo , Dalmau Josep , Gambardella Antonio
Published: May 2013

Background

Patients with anti‐N‐methyl‐D‐aspartate‐glutamic‐receptors (NMDAR) encephalitis often develop complex abnormal movements that may manifest early in the course of illness.

Methods/Results

A 17‐year‐old boy developed paroxysmal exercise‐induced right foot weakness, without behavioral change. Two weeks later, he had hyperthermia and convulsive status epilepticus. Intravenous valproate resolved the status, but the paroxysmal episodes of right foot weakness persisted. They recurred any time he began running, without any refractory period or other triggering factors. Neurological examination between attacks was normal. Ictal video‐polygraphy showed transient loss of lower limb muscle activity without any EEG changes. Results of brain MRI and extensive laboratory tests were normal. NMDAR antibodies were present in liquor and serum. No tumor was found. He was treated with intravenous methylprednisolone plus immunoglobulins with resolution of his symptoms that have not recurred at 8‐month follow‐up.

Conclusions

Our case enlarges the spectrum of abnormal movements as presentation of oligosymptomatic anti‐NMDAR encephalitis. © 2013 Movement Disorder Society
Sleeping Giants: Emerging Roles for the Fat Cadherins in Health and Disease
Authors: Sadeqzadeh Elham , de Bock Charles E. , Thorne Rick F.
Published: May 2013

The vertebrate Fat cadherins comprise a small gene family of four members, Fat1–Fat4, all closely related in structure to Drosophila ft and ft2. Over the past decade, knock‐out mouse studies, genetic manipulation, and large sequencing projects has aided our understanding of the function of vertebrate Fat cadherins in tissue development and disease. The majority of studies of this family have focused on Fat1, with evidence now showing it can bind enable (ENA)/Vasodilator‐stimulated phosphoprotein (VASP), β‐catenin and Atrophin proteins to influence cell polarity and motility; HOMER‐1 and HOMER‐3 proteins to regulate actin accumulation in neuronal synapses; and scribble to influence the Hippo signaling pathway. Fat2 and Fat3 can regulate cell migration in a tissue specific manner and Fat4 appears to influence both planar cell polarity and Hippo signaling recapitulating the activity of Drosophila ft. Knowledge about the exact downstream signaling pathways activated by each family member remains in its infancy, but it is becoming clearer that they have tissue specific and redundant roles in development and may be lost or gained in cancer. In this review, we summarize the recent progress on understanding the role of the Fat cadherin family, integrating the current knowledge of molecular interactions and tissue distributions, together with the accumulating evidence of their changed expression in human disease. The latter is now beginning to promote interest in these molecules as both biomarkers and new targets for therapeutic intervention.
Quantification and correction of respiration induced dynamic field map changes in fMRI using 3D single shot techniques
Authors: Zahneisen Benjamin , Assländer Jakob , LeVan Pierre , Hugger Thimo , Reisert Marco , Ernst Thomas , Hennig Jürgen
Published: May 2013

Purpose

Respiration induced dynamic field map changes in the brain are quantified and the influence on the magnitude signal (physiological noise) is investigated. Dynamic off‐resonance correction allows to reduce the signal fluctuations overlaying the blood oxygenation level dependent signal in
‐weighted functional imaging.

Theory and Methods

A single‐shot whole brain imaging technique with 100 ms temporal resolution was used to measure dynamic off‐resonance maps that were calculated from the incremental changes of the image phase. These off‐resonance maps are then used to dynamically update the off‐resonance corrected reconstruction.

Results

A global resonance offset and a pronounced gradient in head–foot direction were identified as the main components of the change during a respiration cycle. On average, correction for these fluctuations decreases the magnitude fluctuations by around 30%.

Conclusion

Single shot 3D imaging allows for a robust quantification of dynamic off‐resonance changes in the brain. Correction for these fluctuations removes the physiological noise component associated with dynamic point spread function changes. Magn Reson Med 71:1093–1102, 2014. © 2013 Wiley Periodicals, Inc.
Numerical strategy for unbiased homogenization of random materials
Authors: Cottereau R.
Published: May 2013

This paper presents a numerical strategy that allows to lower the costs associated to the prediction of the value of homogenized tensors in elliptic problems. This is performed by solving a coupled problem, in which the complex microstructure is confined to a small region and surrounded by a tentative homogenized medium. The characteristics of this homogenized medium are updated using a self‐consistent approach and are shown to converge to the actual solution. The main feature of the coupling strategy is that it really couples the random microstructure with the deterministic homogenized model, and not one (deterministic) realization of the random medium with a homogenized model. The advantages of doing so are twofold: (a) the influence of the boundary conditions is significantly mitigated, and (b) the ergodicity of the random medium can be used in full through appropriate definition of the coupling operator. Both of these advantages imply that the resulting coupled problem is less expensive to solve, for a given bias, than the computation of homogenized tensor using classical approaches. Examples of 1‐D and 2‐D problems with continuous properties, as well as a 2‐D matrix‐inclusion problem, illustrate the effectiveness and potential of the method. Copyright © 2013 John Wiley & Sons, Ltd.
Central nervous system involvement in anaplastic large cell lymphoma in childhood: Results from a multicentre European and Japanese study
Authors: Williams Denise , Mori Tetsuya , Reiter Alfred , Woessman Wilhelm , Rosolen Angelo , Wrobel Grazyna , Zsiros Jozsef , Uyttebroeck Anne , Marky Ildiko , Le Deley Marie‐Cécile , Brugières Laurence ,   for the European Intergroup for Childhood Non‐Hodgkin Lymphoma, the Japanese Pediatric Leukemia/Lymphoma Study Group
Published: May 2013

In an international study of systemic childhood ALCL, 12/463 patients had CNS involvement, three of which had isolated CNS disease. Comparative analysis of CNS positive and negative patients showed no difference in ALK positivity, immunophenotype, presence of B symptoms or other sites of disease. The lymphohistiocytic variant was over represented in the CNS positive group (36% vs. 5%). With multi‐agent chemotherapy, including high dose methotrexate, Ara‐C and intrathecal treatment, the event free and overall survival of the CNS positive group at 5 years were 50% (95%CI, 25–75%) and 74% (45–91%), respectively with a median follow up of 4.1 years. Pediatr Blood Cancer 2013;60:E118–E121. © 2013 Wiley Periodicals, Inc.
Synthesis of well‐defined side chain fullerene polymers and study of their self‐aggregation behaviors
Authors: Li Junting , Benicewicz Brian C.
Published: May 2013

Monoalkynyl‐functionalized fullerene was precisely synthesized starting with pristine fullerene (C60) and characterized by multiple techniques. Methyl methacrylate and 6‐azido hexyl methacrylate were then randomly copolymerized via reversible addition fragmentation chain transfer polymerization to build polymer backbones with well‐controlled molecular weights and copolymer compositions. Finally, these two moieties were covalently assembled into a series of well‐defined side chain fullerene polymers (SFPs) via the copper‐mediated click reaction which was verified by Fourier transform infrared spectroscopy and 1H NMR. The fullerene loadings of the resultant polymers were estimated by thermogravimetric analysis and UV–vis spectroscopy, demonstrating consistent and high conversions in most of the samples. The morphology studies of the SFPs were performed both in solution and on solid substrates. Very intriguing self‐aggregation behaviors were detected by both gel permeation chromatography and dynamic light scattering analyses. Furthermore, the scanning electron microscopic images of these polymers showed the formation of various supramolecular nanoparticle assemblies and crystalline‐like clusters depending on the fullerene contents and polymer chain lengths. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3572–3582
Research on Titanium‐Containing Micro‐Porous Propellants with Rapid Burning Rate
Authors: Su Jing , Ying Sanjiu , Xiao Zhenggang , Xu Fuming
Published: May 2013

Micro‐porous propellants containing titanium powder were obtained by supercritical CO2 (SC CO2) foaming technique. The morphologies of the micro‐porous propellants were characterized by scanning electron microscopy (SEM) and energy‐dispersive X‐ray spectroscopy (EDS) measurement. The burning rate, the impetus, and the heat of explosion of the micro‐porous propellants were measured by the closed vessel test and the calorimetric bomb test. The results show that the porosity increased with increasing titanium powder content; compared with Benite, the burning rate was substantially improved, and the maximum values of the impetus and the isochoric heat of explosion increased by 51.4 % and 6.5 %, respectively. The Ti‐containing micro‐porous propellants with rapid burning rate and better energetic properties described in this paper may have the potential to replace Benite as igniter material in a flame igniter of a gun propellant charge.
Air stability of PTCDI‐C13‐based n‐OFETs on polymer interfacial layers
Authors: Roh Jeongkyun , Lee Jaemin , Kang Chan‐mo , Lee Changhee , Jung Byung J.
Published: May 2013

This Letter reports the novel use of poly(9‐vinylcarbazole) (PVK) as a dielectric interfacial layer for n‐type organic field‐effect transistors (n‐OFETs). With PVK, both the air stability and electron mobility of N,N′‐ditridecylperylene‐3,4,9,10‐tetracarboxylic diimide (PTCDI‐C13)‐based OFETs were improved. Among the PVKs with different weight‐average molecular weight (Mw), PVK with high Mw showed good performance. The high glass transition temperature of PVK enabled thermal post annealing of the active layer, which resulted in a high electron mobility of 0.61 cm2/Vs. This mobility was maintained at 90% and 59% after 4 days and 105 days in air, respectively. The PVK interfacial layer reduced the trapped charges in the PTCDI‐C13‐based n‐OFET for air‐exposure and caused a decrease in the threshold voltage shift.

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(© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling and formal verification of smart environments
Authors: Corno Fulvio , Sanaullah Muhammad
Published: May 2013

Smart environments SmE are a growing combination of various computing frameworks (ubiquitous, pervasive etc.), devices, control algorithms, and a complex web of interactions. It is at the core of user facilitation in a number of industrial, domestic, and public areas. On the basis of their application areas, SmE may be critical in terms of correctness, reliability, safety, security, etc. To achieve error‐free and requirement‐compliant implementation, these systems are designed by resorting to various modeling approaches including ontology and statecharts. This paper attempts to consider correctness, reliability, safety, and security in the design process of SmE and their related components by proposing a design time modeling and formal verification methodology. The proposed methodology covers various design features related to modeling and formal verification of SmE (focusing on users, devices, environment, control algorithms, and their interaction) against the set of the requirements through model checking. A realistic case study of a Bank Door Security Booth System (BDSB) is tested. The results show the successful verification of the properties related to the safety, security, and desired reliable behavior of BDSB. Copyright © 2013 John Wiley & Sons, Ltd.
Phenotyping the kinematics of leaf development in flowering plants: recommendations and pitfalls
Authors: Lièvre Maryline , Wuyts Nathalie , Cookson Sarah J. , Bresson Justine , Dapp Mélanie , Vasseur François , Massonnet Catherine , Tisné Sébastien , Bettembourg Mathilde , Balsera Crispulo , Bédiée Alexis , Bouvery Frédéric , Dauzat Myriam , Rolland Gaëlle , Vile Denis , Granier Christine
Published: May 2013

Leaves of flowering plants are produced from the shoot apical meristem at regular intervals and they grow according to a developmental program that is determined by both genetic and environmental factors. Detailed frameworks for multiscale dynamic analyses of leaf growth have been developed in order to identify and interpret phenotypic differences caused by either genetic or environmental variations. They revealed that leaf growth dynamics are non‐linearly and nonhomogeneously distributed over the lamina, in the leaf tissues and cells. The analysis of the variability in leaf growth, and its underlying processes, has recently gained momentum with the development of automated phenotyping platforms that use various technologies to record growth at different scales and at high throughput. These modern tools are likely to accelerate the characterization of gene function and the processes that underlie the control of shoot development. Combined with powerful statistical analyses, trends have emerged that may have been overlooked in low throughput analyses. However, in many examples, the increase in throughput allowed by automated platforms has led to a decrease in the spatial and/or temporal resolution of growth analyses. Concrete examples presented here indicate that simplification of the dynamic leaf system, without consideration of its spatial and temporal context, can lead to important misinterpretations of the growth phenotype. WIREs Dev Biol 2013, 2:809–821. doi: 10.1002/wdev.119

This article is categorized under:

Plant Development > Vegetative Development