bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of insects, nutrients, and plant invasion on community structure and function above‐ and belowground
Authors: Wright Phoebe , Cregger Melissa A. , Souza Lara , Sanders Nathan J. , Classen Aimée T.
Published: February 2014

Soil nutrient availability, invasive plants, and insect presence can directly alter ecosystem structure and function, but less is known about how these factors may interact. In this 6‐year study in an old‐field ecosystem, we manipulated insect abundance (reduced and control), the propagule pressure of an invasive nitrogen‐fixing plant (propagules added and control), and soil nutrient availability (nitrogen added, nitrogen reduced and control) in a fully crossed, completely randomized plot design. We found that nutrient amendment and, occasionally, insect abundance interacted with the propagule pressure of an invasive plant to alter above‐ and belowground structure and function at our site. Not surprisingly, nutrient amendment had a direct effect on aboveground biomass and soil nutrient mineralization. The introduction of invasive nitrogen‐fixing plant propagules interacted with nutrient amendment and insect presence to alter soil bacterial abundance and the activity of the microbial community. While the larger‐scale, longer‐term bulk measurements such as biomass production and nutrient mineralization responded to the direct effects of our treatments, the shorter‐term and dynamic microbial communities tended to respond to interactions among our treatments. Our results indicate that soil nutrients, invasive plants, and insect herbivores determine both above‐ and belowground responses, but whether such effects are independent versus interdependent varies with scale.
Determining population structure and hybridization for two iris species
Authors: Hamlin Jennafer A. P. , Arnold Michael L.
Published: February 2014

Identifying processes that promote or limit gene flow can help define the ecological and evolutionary history of a species. Furthermore, defining those factors that make up “species boundaries” can provide a definition of the independent evolutionary trajectories of related taxa. For many species, the historic processes that account for their distribution of genetic variation remain unresolved. In this study, we examine the geographic distribution of genetic diversity for two species ofLouisianaIrises,Iris brevicaulisandIris fulva. Specifically, we asked how populations are structured and if population structure coincides with potential barriers to gene flow. We also asked whether there is evidence of hybridization between these two species outside Louisiana hybrid zones. We used a genotyping‐by‐sequencing approach and sampled a large number of single nucleotide polymorphisms across these species' genomes. Two different population assignment methods were used to resolve population structure inI. brevicaulis; however, there was considerably less population structure inI. fulva. We used a species tree approach to infer phylogenies both within and between populations and species. ForI. brevicaulis,the geography of the collection locality was reflected in the phylogeny. TheI. fulvaphylogeny reflected much less structure than detected forI. brevicaulis. Lastly, combining both species into a phylogenetic analysis resolved two of six populations ofI. brevicaulisthat shared alleles withI. fulva. Taken together, our results suggest major differences in the level and pattern of connectivity among populations of these two Louisiana Iris species.
Electrochemical Determination of Dextromethorphan on Reduced Graphene Oxide Modified Screen‐Printed Electrode after Electromembrane Extraction
Authors: Fakhari Ali Reza , Koruni Mohammad Hossein , Ahmar Hamid , Shahsavani Abolfath , Movahed Siyavash Kazemi
Published: February 2014

In this paper, electromembrane extraction coupled with differential pulse voltammetry (DPV) on a reduced graphene oxide modified screen‐printed carbon electrode (RGO‐SPCE) for the determination of dextromethorphan (DXM) in urine and plasma has been described. DXM migrated from 4 mL of a donor phase across a thin layer of 2‐nitrophenyl octyl ether (NPOE) immobilized in the pores of a porous hollow fiber, into a 20 µL acceptor phase (HCl) present inside the lumen of the fiber. Then, 15 µL of a 0.1 M NaOH solution was added to the acceptor phase and the mixture was analyzed using DPV.
Photoelectrochemical Detection of H2O2 Based on Flower‐Like CuInS2‐Graphene Hybrid
Authors: Wang Siwen , Zhu Yihua , Yang Xiaoling , Li Chunzhong
Published: February 2014

A novel photoelectrochemcial biosensing system was fabricated based on the composition of horseradish peroxidase (HRP), flower‐like CuInS2 (CIS) and graphene on indium tin oxide (ITO) electrode for detecting H2O2. The graphene layer was used as highly conductive scaffolds for electron transport from the ITO electrode to CIS. Furthermore, the flower‐like CIS enhanced the multi‐reflection of light and provided matrixes for the adsorption of HRP. Utilizing one‐pot solvothermal method, we prepared flower‐like CIS‐graphene hybrid (GCIS). Electrochemical tests displayed advantage of graphene with better electron conductivity, and HRP/GCIS showed higher photoelectrochemical behavior.
Quantitative dose–response analysis of ethyl methanesulfonate genotoxicity in adult gpt‐delta transgenic mice
Authors: Cao Xuefei , Mittelstaedt Roberta A. , Pearce Mason G. , Allen Bruce C. , Soeteman‐Hernández Lya G. , Johnson George E. , Bigger C. Anita H. , Heflich Robert H.
Published: February 2014

The assumption that mutagens have linear dose–responses recently has been challenged. In particular, ethyl methanesulfonate (EMS), a DNA‐reactive mutagen and carcinogen, exhibited sublinear or thresholded dose‐responses for LacZ mutation in transgenic Muta™Mouse and for micronucleus (MN) frequency in CD1 mice (Gocke E and Müller L [2009]: Mutat Res 678:101–107). In order to explore variables in establishing genotoxicity dose–responses, we characterized the genotoxicity of EMS using gene mutation assays anticipated to have lower spontaneous mutant frequencies (MFs) than Muta™Mouse. Male gpt‐delta transgenic mice were treated daily for 28 days with 5 to 100 mg/kg EMS, and measurements were made on: (i) gpt MFs in liver, lung, bone marrow, kidney, small intestine, and spleen; and (ii) Pig‐a MFs in peripheral blood reticulocytes (RETs) and total red blood cells. MN induction also was measured in peripheral blood RETs. These data were used to calculate Points of Departure (PoDs) for the dose responses, i.e., no‐observed‐genotoxic‐effect‐levels (NOGELs), lower confidence limits of threshold effect levels (Td‐LCIs), and lower confidence limits of 10% benchmark response rates (BMDL10s). Similar PoDs were calculated from the published EMS dose–responses for LacZ mutation and CD1 MN induction. Vehicle control gpt and Pig‐a MFs were 13–40‐fold lower than published vehicle control LacZ MFs. In general, the EMS genotoxicity dose–responses in gpt‐delta mice had lower PoDs than those calculated from the Muta™Mouse and CD1 mouse data. Our results indicate that the magnitude and possibly the shape of mutagenicity dose responses differ between in vivo models, with lower PoDs generally detected by gene mutation assays with lower backgrounds. Environ. Mol. Mutagen. 55:385–399, 2014. © 2014 Wiley Periodicals, Inc.
An immersed boundary method for fluid flows around rigid objects
Authors: Jendoubi A. , Yakoubi D. , Fortin A. , Tibirna C.
Published: February 2014

In this paper, we present an immersed boundary method for solving fluid flow problems in the presence of static and moving rigid objects. A FEM is used starting from a base mesh that does not represent exactly rigid objects (non‒body‒conforming mesh). At each time step, the base mesh is locally modified to provide a new mesh fitting the boundary of the rigid objects. The mesh is also locally improved using edge swapping to enhance the quality of the elements. The Navier–Stokes equations are then solved on this new mesh. The velocity of moving objects is imposed through standard Dirichlet boundary conditions. We consider a number of test problems and compare the numerical solutions with those obtained on classical body‒fitted meshes whenever possible. Copyright © 2014 John Wiley & Sons, Ltd.
Efficient p‐multigrid discontinuous Galerkin solver for complex viscous flows on stretched grids
Authors: Ghidoni A. , Colombo A. , Bassi F. , Rebay S.
Published: February 2014

Discontinuous Galerkin methods are very well suited for the construction of very high‐order approximations of the Euler and Navier–Stokes equations on unstructured and possibly nonconforming grids but are rather demanding in terms of computational resources. In order to improve their computational efficiency, a p‐multigrid solution strategy is here considered for the solution of the Navier–Stokes equations. In particular, a line smoother will be used to alleviate the effect of stretched grids on the convergence rate. The effectiveness and efficiency of the proposed approach in the solution of compressible shockless flow problems is demonstrated on the following 3D viscous test cases: a Delta Wing and a 3D streamlined body. Copyright © 2014 John Wiley & Sons, Ltd.
The neural correlates of worry in association with individual differences in neuroticism
Authors: Servaas Michelle Nadine , Riese Harriëtte , Ormel Johan , Aleman André
Published: February 2014

The tendency to worry is a facet of neuroticism that has been shown to mediate the relationship between neuroticism and symptoms of depression and anxiety. The aim of the current study was to investigate the neural correlates of state worry in association with neuroticism. One‐hundred twenty participants were selected from an initially recruited sample of 240 women based on their neuroticism score. First, participants completed a questionnaire to assess the excessiveness and uncontrollability of pathological worry. Second, we measured brain activation with functional magnetic resonance imaging (fMRI) while participants were randomly presented with 12 worry‐inducing sentences and 12 neutral sentences in a mood induction paradigm. Individuals scoring higher on neuroticism reported to worry more in daily life and to have generated more worry‐related thoughts after the presentation of a worry‐inducing sentence. Furthermore, imaging results showed the involvement of default mode and emotional brain areas during worry, previously associated with self‐related processing and emotion regulation. Specifically, cortical midline structures and the anterior insula showed more activation during worry, when individuals indicated to have generated more worry‐related thoughts. Activation in the retrosplenial and visual cortex was decreased in individuals scoring higher on neuroticism during worry, possibly suggesting reduced autobiographical specificity and visual mental imagery. In the literature, both these processes have been related to the cognitive avoidance of emotional distress. Excessive worry features in a number of emotional disorders and results from studies that elucidate its neural basis may help explain how and why neuroticism contributes to vulnerability for psychopathology. Hum Brain Mapp 35:4303–4315, 2014. © 2014 Wiley Periodicals, Inc.
Mathematical Properties of the Moments of Truncated Dynamic Magnetic Resonance Spectra and Their Potential Application
Authors: Baram Asher , Luz Zeev
Published: February 2014

The moments of truncated dynamic magnetic resonance spectra, Mn(L), are expanded in terms of power series of the integration range −L to +L. The expansion consists of three contributions: 1) an L‐independent term that, for the first three moments (n=1 to 3), is independent of the motion and equals the corresponding moment, Mn, of the rigid powder spectrum; 2) a limited number of (positive) terms, diverging as Lk (k<n, odd), reflecting the broadening effect due to motion; these terms vanish for the first three moments and become nonzero, with motion‐dependent coefficients, only from the fourth moment on; and 3) an infinite series of converging (negative) terms, in powers of 1/Lk (k is odd), reflecting the reduction of the moments due to the truncation of the spectra; these terms are motion dependent for all moments. The convergence properties of this series are discussed and expressions for the lower (truncated) moments in the slow and fast motion limits of a secular Hamiltonian are derived. For the slow motion limit, it is shown how the L‐dependence of the moments can be used to estimate the magnetic and dynamic parameters. The procedure is demonstrated using computer‐simulated spectra. In the fast motion regime, closed expressions are obtained in a similar form to those of the relaxation equations. The effect of natural line width and strong‐collision dynamics on the various moments as well as that of nonsecular terms in the Hamiltonian are also briefly discussed.
Role of the modulation of CYP1A1 expression and activity in chemoprevention
Authors: Badal S. , Delgoda R.
Published: February 2014

As one of the main extra‐hepatic cytochrome P450 (CYP) enzymes, CYP1A1 has been comprehensively investigated for its ability to metabolize both exogenous and endogenous compounds into their carcinogenic derivatives. These derivatives are linked to cancer initiation and progression. The compound benzo‐a‐pyrene (BaP), a copious and noxious compound present in coal tar, automobile exhaust fumes, cigarette smoke and charbroiled food, is metabolised by CYP1A1 and has been studied in great detail. Other compounds reliant on the same enzyme for their activation include 7,12 dimethylbenz(a)anthracene (DMBA) and heterocyclic amine, 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP). This review takes an in‐depth look at a number of phytochemicals, plant extracts and a few synthetic compounds that have been researched and deemed potential chemopreventives via their interaction with the activity and expression of CYP1A1. It will also review a useful active site model of CYP1A1. Based on inhibitors of CYP1A1 that have demonstrated in vivo use as chemopreventors, CYP1A1 is a useful initial target for screening compounds with such potential, with the use of rapid in vitro and/or in silico assessments. Chemoprevention is a means by which healthy tissues are protected via the prevention, inhibition or reversal of carcinogenesis. This review focuses on one important pathway of carcinogenesis and identifies the important role that CYP1A1 plays in that pathway. It is hoped that highlighting the importance of such a key target, will help revive further research into and application of inhibitors of CYP1A1 towards generating improved chemopreventors. Copyright © 2014 John Wiley & Sons, Ltd.
Development and utilization of an ex vivo bromodeoxyuridine local lymph node assay protocol for assessing potential chemical sensitizers
Authors: Williams W. C. , Copeland C. , Boykin E. , Quell S. J. , Lehmann D. M.
Published: February 2014

The murine local lymph node assay (LLNA) is widely used to identify chemicals that may cause allergic contact dermatitis. Exposure to a dermal sensitizer results in proliferation of local lymph node T cells, which has traditionally been measured by in vivo incorporation of [3H]methyl thymidine. A more recent non‐isotopic variation of the assay utilizes bromodeoxyuridine (BrdU) incorporation in vivo. To further improve the utility of this assay, we developed an ex vivo BrdU labeling procedure eliminating the need for in vivo injections. The results of this assay correctly identified a strong sensitizer (i.e., trimellitic anhydride) as well as weak/moderate sensitizers (i.e., eugenol, cinnamaldehyde and hexylcinnaminic aldehyde). As anticipated, neither non‐sensitizers isopropanol and lactic acid nor the false negative chemical nickel II sulfate hexahydrate induced a positive threshold response in the assay. The results of this assay are in close agreement with those of the in vivo LLNA:BrdU‐enzyme‐linked immunosorbent assay labeling procedure. We also used the ex vivo BrdU LLNA procedure to evaluate ammonium hexachloroplatinate, ammonium tetrachloroplatinate and cis‐diamminedichloroplatinum(II) and the assay correctly identified them as sensitizers based on the calculation of EC2 values. We conclude that this ex vivo BrdU labeling method offers predictive capacity comparable to previously established LLNA protocols while eliminating animal injections and the use of radioisotope. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
ARRY‐334543 Reverses Multidrug Resistance by Antagonizing the Activity of ATP‐Binding Cassette Subfamily G Member 2
Authors: Wang De‐Shen , Patel Atish , Sim Hong‐May , Zhang Yun‐Kai , Wang Yi‐Jun , Kathawala Rishil J. , Zhang Hui , Talele Tanaji T. , Ambudkar Suresh V. , Xu Rui‐Hua , Chen Zhe‐Sheng
Published: February 2014

ARRY‐334543 is a small molecule inhibitor of ErbB1 and ErbB2 tyrosine kinases. We conducted this study to determine whether ARRY‐334543 can enhance the efficacy of conventional anticancer drugs through interaction with ABC transporters. Lung cancer cell line NCI‐H460 and its ABCG2‐overexpressing NCI‐H460/MX20, as well as the ABCG2‐, ABCB1‐, and ABCC10‐overexpressing transfected cell lines were used for the reversal study. Our results demonstrated that ARRY‐334543 (1.0 μM) significantly reversed ABCG2‐mediated multidrug resistance (MDR) by directly inhibiting the drug efflux function of ABCG2, resulting in the elevated intracellular accumulation of chemotherapeutic drugs in the ABCG2‐overexpressing cell lines. In addition, in isolated membranes, ARRY‐334543 stimulated ATPase activity and inhibited photolabeling of ABCG2 with [125I]‐iodoarylazidoprazosin in a concentration‐dependent manner indicating that this drug directly interacts at the drug‐binding pocket of this transporter. ARRY‐334543 (1.0 μM) only slightly reversed ABCB1‐ and partially reversed ABCC10‐mediated MDR suggesting that it exhibits high affinity toward ABCG2. Moreover, homology modeling predicted the binding conformation of ARRY‐334543 at Arg482 centroid‐based grid of ABCG2. However, ARRY‐334543 at reversal concentrations did not affect the expression level of ABCG2, AKT and ERK1/2 and regulate the re‐localization of ABCG2. We conclude that ARRY‐334543 significantly reverses drug resistance mediated by ABCG2. J. Cell. Biochem. 115: 1381–1391, 2014. © 2014 Wiley Periodicals, Inc.
Creating an Instrument to Measure Leadership, Change, and Synthesis in Engineering Undergraduates
Authors: Ahn Benjamin , Cox Monica F. , London Jeremi , Cekic Osman , Zhu Jiabin
Published: February 2014

Background

Studies have highlighted the importance for engineers of leadership, adaptability to change, and synthesis of multiple perspectives. Yet only a few studies and instruments have explored the operational definitions of these concepts for engineering undergraduates.

Purpose

The goals of this research were to identify observable outcomes that engineering undergraduate students should demonstrate related to leadership, adaptability to change, and synthesis abilities and to create an instrument to assess them.

Design/Method

In the first phase of the study, 12 engineers working in academia and 11 engineers working in industry were interviewed. The transcripts were analyzed using a constant comparative method to determine constructs related to leadership, change, and synthesis. In the second phase of the study, survey items were developed and administered to 753 engineering undergraduate students in the spring of 2011. An exploratory factor analysis determined the common factors across the survey items.

Results

The mixed methods approach resulted in the creation of 45 survey items categorized into four factors: Being an Engineering Leader, Engineer's Impact on Society and Economy, Engineering Leadership, and Development of an Adaptor to Change.

Conclusion

This study operationalized leadership, change, and synthesis within the context of engineering education. This operationalization may help to define learning outcomes and competencies for engineering leadership programs, and may provide faculty with an assessment tool for their students. Students may also use the tool to self‐assess their leadership, change, and synthesis abilities.
Systematic Literature Reviews in Engineering Education and Other Developing Interdisciplinary Fields
Authors: Borrego Maura , Foster Margaret J. , Froyd Jeffrey E.
Published: February 2014

Background

In fields such as medicine, psychology, and education, systematic reviews of the literature critically appraise and summarize research to inform policy and practice. We argue that now is an appropriate time in the development of the field of engineering education to both support systematic reviews and benefit from them. More reviews of prior work conducted more systematically would help advance the field by lowering the barrier for both researchers and practitioners to access the literature, enabling more objective critique of past efforts, identifying gaps, and proposing new directions for research.

Purpose

The purpose of this article is to introduce the methodology of systematic reviews to the field of engineering education and to adapt existing resources on systematic reviews to engineering education and other developing interdisciplinary fields.

Scope/Method

This article is primarily a narrative review of the literature on conducting systematic reviews. Methods are adapted to engineering education and similar developing interdisciplinary fields. To offer concrete, pertinent examples, we also conducted a systematic review of systematic review articles published on engineering education topics since 1990. Fourteen exemplars are presented in this article and used to illustrate systematic review procedures.

Conclusions

Systematic reviews can benefit the field of engineering education by synthesizing prior work, by better informing practice, and by identifying important new directions for research. Engineering education researchers should consider including systematic reviews in their repertoire of methodologies.
Optimization of the preparation of fluorine‐18‐labeled steroid receptor ligands 16alpha‐[18F]fluoroestradiol (FES), [18F]fluoro furanyl norprogesterone (FFNP), and 16beta‐[18F]fluoro‐5alpha‐dihydrotestosterone (FDHT) as radiopharmaceuticals
Authors: Zhou Dong , Lin Mai , Yasui Norio , Al‐Qahtani Mohammed H. , Dence Carmen S. , Schwarz Sally , Katzenellenbogen John A.
Published: February 2014

Fluorine‐18‐labeled steroid receptor tracers, 16α‐[18F]fluoroestradiol (FES), [18F]fluoro furanyl norprogesterone (FFNP), and 16β‐[18F]fluoro‐5α‐dihydrotestosterone (FDHT), are important imaging tools for studies of breast and prostate cancers using positron emission tomography (PET). The automated production of these ligands with high specific activity (SA) as radiopharmaceuticals requires modification and optimization of the currently reported methods. [18F]FES with high SA was synthesized in over 60% radiochemical yield (RCY) at the end of synthesis (EOS) using a small amount of precursor (1) (as low as 0.3 mg) and 1 M H2SO4 for deprotection of the intermediate (2). [18F]FFNP was synthesized in up to 77% RCY at EOS using the triflate precursor (4) at room temperature or in 25% RCY using the mesylate precursor (6) at 65°C. Both methods are highly reproducible and afford high SA. [18F]FDHT was synthesized by radiofluoride incorporation at room temperature, reduction with NaBH4, and deprotection with HCl/acetone, giving [18F]FDHT in up to 75% yield (RCY). All of these methods can be easily translated to automated production. The information provided here will aid in the development of automated production of these steroid receptor tracers with high or improved yields, optimal SA, and ease of processing for research and clinical use. Copyright © 2014 John Wiley & Sons, Ltd.
Differentiating white matter lesions in multiple sclerosis and migraine using monoexponential and biexponential diffusion measurements
Authors: Orsi Gergely , Aradi Mihály , Nagy Szilvia Anett , Perlaki Gábor , Trauninger Anita , Bogner Péter , Janszky József , Illés Zsolt , Dóczi Tamás , Pfund Zoltán , Schwarcz Attila
Published: February 2014

Purpose

To compare the white matter lesions seen in multiple sclerosis and migraine using monoexponential and high b‐value biexponential diffusion measurements.

Materials and Methods

Diffusion‐weighted images were acquired on a 3.0‐Tesla magnetic resonance imaging system. Diffusion parameters were estimated using monoexponential (0–1000 s/mm2) and biexponential (0–5000 s/mm2) approaches from 15 multiple sclerosis patients, 15 patients with migraine and 15 healthy control subjects. The study was performed in accordance with the approval of the Regional Research Ethics Committee. The apparent diffusion coefficient (ADC) values were measured in the lesions and the normal‐appearing white matter of patients and in the white matter of controls.

Results

High lesional ADCmono values were detected in both patient groups without significant differences between the groups (10.72 and 9.86 × 10−4 mm2/s for MS and migraine respectively, P = 0.2134). The biexponential measurements showed significantly higher ADCfast, ADCslow, and Pslow values in the migraine lesions than in the multiple sclerosis lesions (16.47 versus 14.29, 1.41 versus 0.76, and 20.34 versus 12.01 all values in 10−4 mm2/s; P = 0.0344, P = 0.0019, P = 0.0021, respectively).

Conclusion

Biexponential diffusion analysis may help to differentiate multiple sclerosis‐related white matter lesions from migraine‐related ones. J. Magn. Reson. Imaging 2015;41:676–683. © 2014 Wiley Periodicals, Inc.
Prospective comparison of 3T MRI with diffusion‐weighted imaging and MDCT for the preoperative TNM staging of gastric cancer
Authors: Joo Ijin , Lee Jeong Min , Kim Jung Hoon , Shin Cheong‐Il , Han Joon Koo , Choi Byung Ihn
Published: February 2014

Purpose

To compare the diagnostic performance of 3T magnetic resonance imaging (MRI) with diffusion‐weighted imaging (DWI) and multidetector‐row computed tomography (MDCT) for the preoperative TNM staging of gastric cancer.

Materials and Methods

This prospective study was approved by our Institutional Review Board. Forty‐nine consecutive patients with histologically confirmed gastric cancers underwent MDCT and 3T MRI followed by surgery. MRI without DWI, MRI with DWI, and MDCT were reviewed to determine preoperative TNM staging. Using the pathologic stages as the reference standard, the diagnostic performance of each imaging modality was compared.

Results

Diagnostic accuracies of MRI with DWI, MRI without DWI, and MDCT did not show a significant difference (≤T2 vs. ≥T3: 85.1%, 78.7%, and 80.9%; ≤T3 vs. T4: 76.6%, 74.5%, and 72.3%; N‐negative vs. N‐positive: 76.6%, 66.0%, and 63.8%; M0 vs. M1: all 95.9%, respectively) (P > 0.05). For N staging, MRI with DWI demonstrated higher sensitivity but lower specificity (86.7% and 58.8%, respectively) than MRI without DWI (50.0% and 94.1%) or MDCT (43.3% and 100%) (P < 0.05).

Conclusion

The diagnostic accuracy of 3T MRI is comparable to that of MDCT for the preoperative TNM staging of gastric cancer, and for assessing LN metastasis, the addition of DWI to conventional MRI may increase the sensitivity. J. Magn. Reson. Imaging 2015;41:814–821. © 2014 Wiley Periodicals, Inc.
Spatial distribution of air temperature on Svalbard during 1 year with campaign measurements
Authors: Przybylak R. , Araźny A. , Nordli Ø. , Finkelnburg R. , Kejna M. , Budzik T. , Migała K. , Sikora S. , Puczko D. , Rymer K. , Rachlewicz G.
Published: February 2014

In this article, the results of an investigation into the air temperature conditions on Svalbard in the period 1 September 2010 to 31 August 2011 are presented. For this period, parallel temperature measurements have been made as many as in 30 sites. On the basis of this unique set of data it was possible to study, in detail, the spatial distribution of different thermal characteristics [mean temperature, diurnal temperature range (DTR), day‐to‐day variability, degree of climate continentality, etc.] in Svalbard. Such knowledge of the whole of Svalbard was not previously available with sufficient accuracy for all areas. High resolution maps showing the spatial distribution of all studied thermal characteristics were also produced and analysed.

Analysis of surface temperature data shows that the markedly coldest area throughout the whole year was northern Svalbard, and in particular its eastern side (Nordaustlandet). On the other hand, the highest temperatures were recorded in western part of Spitsbergen. The greatest spatial decreasing rate of temperature in Svalbard throughout the whole year was observed in a southwest (SW)–northeast (NE) direction. The distribution of mean seasonal and annual temperature reduced to sea level on Svalbard differs from the distribution based on surface temperatures. Spring, and in particular winter, saw the greatest DTRs (4–7 and 6–9 °C, respectively), while the lowest were observed in summer (3.0–3.5 °C). In all seasons, the highest DTR were mainly noted in the NE part of Svalbard, while the lowest were in its SW part. The lowest continentality of climate (30%) is clearly seen in the south‐western part of Svalbard, while the highest values (above 43%) stretch from the western part of Nordaustlandet to the area of Sveagruva in the central‐eastern part of Spitsbergen. The NORA10 hindcast temperature data differ significantly from measured data for some seasons and areas and need bias corrections when used in climatology.
Characterization of colorants and opacifiers in roman glass mosaic tesserae through spectroscopic and spectrometric techniques
Authors: Basso E. , Invernizzi C. , Malagodi M. , La Russa M. F. , Bersani D. , Lottici P. P.
Published: February 2014

Several glass mosaic tesserae were recovered during the archeological excavation of the thermal baths at the ‘Villa dei Quintili’ in Rome and dated to the second century ad. This work reports the results of an archeometrical investigation performed, through a multi‐technique approach, on 19 colored opaque tesserae. The aims of the study were (1) the characterization of coloring and opacifying agents used for the production of the glass tesserae and (2) the definition of the technological processes involved. Colorimetric measurements allowed us to classify the tesserae in color groups, while the glassy matrix and the dispersed crystallites were characterized in detail through micro‐Raman spectroscopy, field emission scanning electron microscopy with energy dispersive X‐ray spectroscopy, laser ablation‐inductively coupled plasma‐mass spectrometry, and X‐ray powder diffraction analyses. Most of the glass shows the typical soda‐lime‐silicate composition (except for the orange and red tesserae). Raman results and elemental analysis prove the use of Sn–Pb antimonates to create yellow glass and of Ca‐antimonates for the white tesserae. A mixture of Sn–Pb antimonates and copper ions was used to obtain the emerald green color, while Ca‐antimonates were employed in both copper‐colored and cobalt‐colored blue glass to obtain different shades (blue‐green, dark, and light blue). X‐ray powder diffraction analyses reveal the presence of metallic copper (Cu0) and Cu2O particles (cuprite) in red and orange tesserae, respectively. These results confirm the high technological level reached by the glassmakers of the Imperial Age. Copyright © 2014 John Wiley & Sons, Ltd.
Modelling fireside corrosion of thermal sprayed coatings in co‐firing of coal/biomass
Authors: Hussain T. , Simms N. J. , Nicholls J. R.
Published: February 2014

This paper presents a development and evaluation of coating materials for advanced fossil fuel plants and addresses issues related to coal/biomass‐derived flue gases. A selection of candidate coatings: 625, NiCr and NiCrAlY were deposited on superheater/reheater materials (T91) using high velocity oxy‐fuel (HVOF) spraying. A series of laboratory‐based fireside corrosion exposures have been carried out on these coated samples in controlled atmosphere furnaces for 1000 h. The tests were carried out with the “deposit‐recoat” test method to generate the exposure conditions; the gaseous environment simulated that anticipated from air‐firing 20 wt% cereal co‐product (CCP) mixed with a UK coal. The exposures were carried out using various mixtures of Na2SO4, K2SO4, Fe2O3 and kaolinite to produce different deposition fluxes at a test temperature of 650 °C. After the exposures, the samples were examined by environmental scanning electron microscope/energy dispersive X‐ray analysis to characterise the damage. Pre‐ and post‐exposure dimensional metrology was used to quantify the metal damage in terms of metal loss distributions. In all three coatings, the deposit targeted at forming undiluted alkali‐iron tri‐sulphate was found to be the most aggressive, causing the most corrosion damage to all alloys in simulated air‐fired combustion gases. A corrosion model was proposed to predict the incubation time at different alkali deposition fluxes. The transition from incubation to propagation was found to be dependent on the chromium content of the alloys. The HVOF NiCr coating, with 46 wt% chromium, was found to be the best performing coating with the longest incubation times in these tests.
Microstructure‐based characterization of the corrosion behavior of the creep resistant Mg–Al–Ba–Ca alloy DieMag422
Authors: Klein M. , Kuhlmann F. , Wittke P. , Dieringa H. , Walther F.
Published: February 2014

The corrosion behavior as well as the microstructure in initial state and after corrosive deterioration were investigated for the newly developed Mg–Al–Ba–Ca alloy DieMag422. In order to investigate the corrosion behavior, potentiodynamic polarization measurements and immersion tests were performed in different NaCl concentrations. The microstructure was observed using light microscopy and combined SEM and EDX studies of the specimens before and after corrosive deterioration. Potentiodynamic polarization measurements and immersion tests showed that DieMag422 has a strong susceptibility to corrosion in NaCl solutions. Light microscope and SEM studies revealed that the difference in the corrosion behavior can be attributed to the different occurrence of the anodic α‐Mg phase and the cathodic Ca‐rich phase.
Predictive factors of speech intelligibility following subthalamic nucleus stimulation in consecutive patients with Parkinson's disease
Authors: Tripoliti Elina , Limousin Patricia , Foltynie Tom , Candelario Joseph , Aviles‐Olmos Iciar , Hariz Marwan I. , Zrinzo Ludvic
Published: February 2014

Speech changes after bilateral subthalamic nucleus deep brain stimulation (STN‐DBS) can be variable, with the majority of patients experiencing speech deterioration over time. The aim of this study was to describe the perceptual characteristics of speech following chronic STN‐DBS and to analyze clinical and surgical factors that could predict speech change. Fifty‐four consecutive patients (34 men; mean age ± standard deviation (SD), 58.8 ± 6.3 years; mean ± SD disease duration, 12.5 ± 4.7 years; mean ± SD levodopa equivalent, 1556 ± 671 mg/day; mean ± SD Unified Parkinson's Disease Rating Scale motor part (UPDRS‐III) off‐medication score, 48.1 ± 17.9 [range, 20‐89]; and mean ± SD UPDRS‐III on‐medication score, 12.4 ± 7.8 [range, 2‐31]) participated in this study. They were assessed before and at 1 year after surgery using the Assessment of Intelligibility for the Dysarthric Speech, the perceptual scale from Darley et al., and the UPDRS‐III. Speech intelligibility deteriorated on average by 14.4% (P = 0.0006) after 1 year of STN‐DBS when off‐medication and by 12.3% (P = 0.001) when on‐medication. The effect on speech was not linked to age at surgery, unlike the effect on motor outcome. The most significant predictive factors for deterioration of speech intelligibility when patients were off‐medication/on‐stimulation were lower preoperative speech intelligibility on‐medication, longer disease duration, and medially placed left hemisphere active electrode contact. Speech change after STN‐DBS is variable and multifactorial. Consistent preoperative speech evaluation would help inform patients about the possible effects of surgery. Appropriate consideration of speech deficits might assist surgical targeting, particularly of the left electrode. © 2014 International Parkinson and Movement Disorder Society
Factors contributing to tornadogenesis in landfalling Gulf of Mexico tropical cyclones
Authors: Rhodes Cory L. , Senkbeil Jason C.
Published: February 2014

Tropical cyclone tornadoes (TCTs) are brief and often unpredictable events that can produce fatalities and create considerable economic loss. Given these uncertainties, it is important to understand the characteristics and factors that contribute to tornado formation within tropical cyclones. This research analyses this hazardous phenomenon, examining the relationships among tropical cyclone intensity, size and tornado output. Furthermore, the influences of severe weather parameters on tornado output near the time of tornado formation were assessed between two phases of a tropical cyclone's life cycle: during hurricane and tropical storm intensity, termed tropical cyclone tornadoes (TCTs), and during tropical depression and remnant low intensity, termed tropical low tornadoes (TLTs). Results show that tornado output is significantly influenced by tropical cyclone intensity. Values for storm relative helicity, energy helicity index, and severe weather threat index are significantly higher within TCT environments, thus resulting in more tornadoes.
Monitoring Polymerization Kinetics in Microreactors by Confocal Raman Microscopy
Authors: Yadav Arvind Kumar , Krell Manfred , Hergeth Wolf‐Dieter , de la Cal José Carlos , Barandiaran María Jesús
Published: February 2014

On‐line monitoring of polymerization reactions in microreactors is investigated by confocal Raman microscopy (CRM). Two different types of experiments are carried out: solution polymerizations and miniemulsion polymerizations. The solution polymerization experiments are performed with either styrene or butyl acrylate (BA) monomers, while toluene is used as solvent in both cases. BA is the only monomer used in the miniemulsion polymerizations. Conversion is determined by CRM for different residence times and the results are compared with the ones obtained gravimetrically. The good agreement achieved in all the experiments demonstrates that CRM is an appropriate technique to on‐line monitoring the kinetics of polymerizations performed in microreactors.
Phase contrast MRI with flow compensation view sharing
Authors: Wang Da , Shao Jiaxin , Rapacchi Stanislas , Middione Matthew J. , Ennis Daniel B. , Hu Peng
Published: February 2014

Purpose

To develop and evaluate a technique for accelerating phase contrast MRI (PC‐MRI) acquisitions without significant compromise in flow quantification accuracy.

Methods

PC‐MRI is commonly acquired using interleaved flow‐compensated (FC) and flow‐encoded (FE) echoes. We hypothesized that FC data, which represent background phase, do not change significantly over time. Therefore, we proposed to undersample the FC data and use an FC view sharing (FCVS) approach to synthesize a composite FC frame for each corresponding FE frame. FCVS was evaluated in a flow phantom and healthy volunteers and compared with a standard FC/FE PC‐MRI.

Results

The FCVS sequence resulted in an error of 0.0% for forward flow and 2.0% for reverse flow volume when compared with FC/FE PC‐MRI in a flow phantom. Measurements in the common carotid arteries showed that the FCVS method had −1.16 cm/s bias for maximum peak velocity and −0.019 mL bias in total flow, when compared with FC/FE with the same temporal resolution, but double the total acquisition time. These results represent ≤1.3% bias error in velocity and volumetric flow quantification.

Conclusion

FCVS can accelerate PC‐MRI acquisitions while maintaining flow and velocity measurement accuracy when there is limited temporal variation in the FC data. Magn Reson Med 73:505–513, 2015. © 2014 Wiley Periodicals, Inc.
Mixed interior penalty discontinuous Galerkin methods for fully nonlinear second order elliptic and parabolic equations in high dimensions
Authors: Feng Xiaobing , Lewis Thomas
Published: February 2014

This article is concerned with developing efficient discontinuous Galerkin methods for approximating viscosity (and classical) solutions of fully nonlinear second‐order elliptic and parabolic partial differential equations (PDEs) including the Monge–Ampère equation and the Hamilton–Jacobi–Bellman equation. A general framework for constructing interior penalty discontinuous Galerkin (IP‐DG) methods for these PDEs is presented. The key idea is to introduce multiple discrete Hessians for the viscosity solution as a means to characterize the behavior of the function. The PDE is rewritten in a mixed form composed of a single nonlinear equation paired with a system of linear equations that defines multiple Hessian approximations. To form the single nonlinear equation, the nonlinear PDE operator is replaced by the projection of a numerical operator into the discontinuous Galerkin test space. The numerical operator uses the multiple Hessian approximations to form a numerical moment which fulfills consistency and g‐monotonicity requirements of the framework. The numerical moment will be used to design solvers that will be shown to help the IP‐DG methods select the “correct” solution that corresponds to the unique viscosity solution. Numerical experiments are also presented to gauge the effectiveness and accuracy of the proposed mixed IP‐DG methods.Copyright © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1538–1557, 2014
Inflammatory disease of the central nervous system induced by anti‐GD2 monoclonal antibody in a patient with high risk neuroblastoma
Authors: Zama Daniele , Morello William , Masetti Riccardo , Cordelli Duccio Maria , Massaccesi Erika , Prete Arcangelo , Pession Andrea
Published: February 2014

Pediatr Blood Cancer 2014; 61:1521–1522. © 2014 Wiley Periodicals, Inc.
Proteoform analysis of lipocalin‐type prostaglandin D‐synthase from human cerebrospinal fluid by isoelectric focusing and superficially porous liquid chromatography with Fourier transform mass spectrometry
Authors: Zhang Junmei , Corbett John R. , Plymire Daniel A. , Greenberg Benjamin M. , Patrie Steven M.
Published: February 2014

Lipocalin‐type prostaglandin D‐synthase (L‐PGDS) in cerebrospinal fluid contributes to the maturation and maintenance of the CNS. L‐PGDS PTMs may contribute to pathobiology of different CNS diseases, but methods to monitor its proteoforms are limited. Herein, we combined off‐gel IEF and superficially porous LC (SPLC) with Fourier transform MS to characterize common cerebrospinal fluid L‐PGDS proteoforms. Across 3D physiochemical space (pI, hydrophobicity, and mass), 217 putative proteoforms were observed from 21 to 24 kDa and pI 5–10. Glycoprotein accurate mass information, combined with MS/MS analysis of peptides generated from 2D‐fractionated proteoforms, enabled the putative assignment of 208 proteoforms with varied PTM positional occupants. Fifteen structurally related N‐glycans at N29 and N56 were observed, with different N‐glycan compositional variants being preferred on each amino acid. We also observed that sialic acid content was a major factor for pI shifts between L‐PGDS proteoforms. Other putative PTMs characterized include a core‐1 HexHexNAc‐O‐glycan at S7, acetylation at K16 and K138, sulfonation at S41 and T142, and dioxidation at C43 and C145. The IEF‐SPLC‐MS platform presented provides 30–40× improved peak capacity versus conventional 2DE and shows potential for repeatable proteoform analysis of surrogate PTM‐based biomarkers.
Controlled cationic alternating copolymerization of various enol ethers and benzaldehyde derivatives: Effects of enol ether structures
Authors: Ishido Yasushi , Kanazawa Arihiro , Kanaoka Shokyoku , Aoshima Sadahito
Published: February 2014

Significant structural effects of enol ether monomers were demonstrated in cationic alternating copolymerizations with benzaldehyde derivatives (BzAs). α‐Methyl, β‐methyl, β,β‐dimethyl, and cyclic enol ethers were copolymerized with BzAs by the EtSO3H/GaCl3 system with 1,4‐dioxane in toluene at −78 °C. β‐Methyl and cyclic monomers, β‐monosubstituted compounds, induced copolymerizations with BzAs, some of which were well controlled to yield alternating copolymers with controlled molecular weights (MWs) and narrow MW distributions. Conversely, an α‐methyl vinyl ether (VE) did not copolymerize with BzAs at all, probably due to its high reactivity and unfavorable ketal linkage formations. In addition, a β,β‐dimethyl VE underwent only cyclotrimerizations because of its larger steric repulsion. The product alternating copolymers, especially those with cyclic units, exhibited improved thermal properties compared to those with simple VEs units. Under appropriate conditions, the alternating copolymers selectively degraded into the corresponding cinnamaldehyde derivatives by acid hydrolysis. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1334–1343
Characteristics of endobronchial primitive tumors in children
Authors: Eyssartier E. , Ang P. , Bonnemaison E. , Gibertini I. , Diot P. , Carpentier E. , Chantepie A. , Leclair M.D. , Brouard J. , Boutard P. , Deneuville E. , Marie‐Cardine A. , Lardy H.
Published: February 2014

Primary endobronchial tumors are rare in children and they include a broad spectrum of lesions. The aim of this study was to determine the characteristic features, treatments and outcomes of these tumors. We report a retrospective analysis of all patients treated for endobronchial tumor in nine French hospitals between 1990 and 2010 and a comparison of the results with those reported in the medical literature.

Twelve tumors were reported: five low grade muco epidermoid carcinomas, two inflammatory myofibroblastic tumors, two hemangiomas, one anaplastic large cell lymphoma, one carcinoid tumor, and one juvenile xanthogranuloma. The mean age of the patients was 7.5 ± 3.5 years. The most common sign revealing the disease was persistent atelectasis or recurrent pneumonia (eight cases). The other revealing signs were a persistent bronchospasm (three cases) and hemoptysis (one case). The clinical presentation, biology, serum tumor markers, and chest X‐ray abnormalities were not specific to a particular histological diagnosis. Chest CT scan revealed the presence of an endobronchial tumor in 11 cases. Nine tumors could be diagnosed from a biopsy obtained by video endoscopy. Complete surgical resection was performed in seven patients. Bronchoscopic removal was performed in five cases and was successful in three. There were no deaths.

Endobronchial tumors are rare in childhood and their histology is diverse. Chest CT scan and per‐endoscopic endobronchial biopsies are required for diagnosis, when possible. Surgical or endoscopic treatment should be discussed by a multidisciplinary team. Despite the multiple etiologies, the prognosis of these tumors is good if diagnosis is early and if resection is complete. Long‐term recurrences have been described, so long‐term follow‐up of these children is recommended. Pediatr Pulmonol. 2014; 49:E121–E125. © 2014 Wiley Periodicals, Inc.