bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seismic anisotropy of serpentinite from Val Malenco, Italy
Authors: Kern Hartmut , Lokajicek Tomas , Svitek Tomas , Wenk Hans‐Rudolf 
Published: May 2015

AbstractSerpentinites, deformed in mantle subduction zones, are thought to contribute significantly to seismic anisotropy of the upper mantle and have therefore been of great interest with studies on deformation, preferred orientation, and elastic properties. Here we present a combined study of a classical sample from Val Malenco, Italy, investigating the microstructure and texture with state‐of‐the art synchrotron X‐ray and neutron diffraction methods and measuring ultrasonic velocities both with a multi‐anvil apparatus and a novel instrument to measure 3‐D velocities on spheres. Both, results from diffraction methods and velocity measurements are compared, discussing advantages and disadvantages. From spherical velocities, elastic tensor properties can be derived by inversion. Also from quantitative texture measurements, elastic properties can be modeled by self‐consistent averaging. Good agreement between the velocity and microstructural models is observed.
Role of Multiwalled Carbon Nanotubes Localization on Morphology Development of PMMA/PS/PP Ternary Blends
Authors: Rostami Amir , Nazockdast Hossein , Karimi Mohammad , Javidi Zeinab 
Published: May 2015

ABSTRACTIn this work, we studied the parameters affecting the localization of multiwalled carbon nanotubes (MWCNTs) and its impact on morphology development of poly(methyl methacrylate)/polystyrene/polypropylene (PMMA/PS/PP) ternary blends, which originally have a thermodynamically preferred core–shell type morphology. We compared the results with the morphological prediction based on the thermodynamic approach. The MWCNTs localization and morphological features of nanocomposite samples were studied by means of melt linear viscoelastic experiments together with electron microscopy results. It was found that at 0.5 wt% of MWCNTs the original core–shell type morphology of the ternary blend samples almost remained intact. and this observation was independent of the sequence of feeding. At 1 wt% of MWCNTs, the core–shell morphology was retained only for those nanocomposite samples prepared using the sequential feeding mode. In addition, it was demonstrated that the thermodynamic predictions could be utilized for the nanocomposites containing low MWCNTs contents. However, this was not true for the nanocomposites with higher MWCNTs contents due to the predominating role of viscoelastic properties of the PS shell.
Relationship between maternal and newborn endothelial function and oxidative stress
Authors: Echeverri Isabella , Ortega–Ávila José Guillermo , Mosquera Mildrey , Castillo Andrés , Jiménez Eliécer , Suárez‐Ortegon Milton Fabian , Mateus Julio Cesar , Aguilar‐de Plata Cecilia 
Published: May 2015

ObjectiveTo evaluate the Relationship between maternal and newborn endothelial function and oxidative stress.MethodsForty‐three pregnant women and their offspring were evaluated. As markers of endothelial function, the flow‐mediated dilation (FMD) was measured in pregnant women in the second and third trimesters, and nitric oxide (NO) was quantified in the endothelial cells of the umbilical cord vein. Malondialdehyde (MDA), as a marker of oxidative stress, was measured in the maternal plasma (second and third trimesters) and plasma from umbilical cord blood. Gestational age and birth weight were recorded. Correlations between variables were estimated, and adjustments were made for specific gestational week of measurement, gestational age at birth, and complications during pregnancy and/or at delivery.ResultsMaternal FMD at second trimester correlated positively with newborn MDA, although with marginal significance (P = 0.090). The change in maternal FMD was positively correlated with newborn NO (P = 0.039), although adjustment for gestational age and specific week of gestation attenuated this relationship (P = 0.070). Maternal MDA at second trimester correlated positively with newborn MDA independently of gestational age at birth, specific week of gestation of the measurement, and having complications during pregnancy or at delivery (P = 0.032). After adjustments, the change in maternal MDA correlated with newborn MDA but marginally (P = 0.077).ConclusionStudy findings suggest that under physiological conditions, enhanced endothelial function and/or oxidative stress in the mother may impact on normal fetal development. Future studies are recommended, employing larger sample sizes, a more extensive set of markers of oxidative stress, and comparisons of complicated versus normal pregnancies. Am. J. Hum. Biol. 27:822–831, 2015. © 2015 Wiley Periodicals, Inc.
Cohort study of physical activity and injury among Latino farm workers
Authors: Xiao Hong , Stoecklin‐Marois Maria , Li Chin‐Shang , McCurdy Stephen A. , Schenker Marc 
Published: May 2015

IntroductionThis study characterized physical activity and its association with injury among Latino farm workers.MethodsAn interviewer‐administered questionnaire was used to collect baseline and follow‐up data on 843 and 640 Latino farm workers, respectively. Participants were 18–55 years old, engaged in farm work and residing in Mendota, CA at baseline interview. The questionnaire assessed self‐reported physical activity and risk of injury.ResultsThe 12 month prevalence of injury decreased from 9.0% at baseline to 6.9% at follow up interview. In GEE models adjusted for age, follow‐up time, gender, smoking, income and years working in agriculture, poor/fair self‐assessed health status (OR = 1.82, 95% CI: 1.18–2.82) and 2–3 hr per day of sitting/watching TV/using a computer (OR = 0.50, 95% CI: 0.30–0.83) were significantly associated with injury.ConclusionsPhysical activity was not associated with injury in this population. Efforts to reduce injuries should focus on known risk factors such as poor health status. Am. J. Ind. Med. 58:737–745, 2015. © 2015 Wiley Periodicals, Inc.
Occupational exposures and risk of dementia‐related mortality in the prospective Netherlands Cohort Study
Authors: Koeman Tom , Schouten Leo J. , van den Brandt Piet A. , Slottje Pauline , Huss Anke , Peters Susan , Kromhout Hans , Vermeulen Roel 
Published: May 2015

BackgroundOccupational exposures may be associated with non‐vascular dementia.MethodsWe analyzed the effects of occupational exposures to solvents, pesticides, metals, extremely low frequency magnetic fields (ELF‐MF), electrical shocks, and diesel motor exhaust on non‐vascular dementia related mortality in the Netherlands Cohort Study (NLCS). Exposures were assigned using job‐exposure matrices. After 17.3 years of follow‐up, 682 male and 870 female cases were available. Analyses were performed using Cox regression.ResultsOccupational exposure to metals, chlorinated solvents and ELF‐MF showed positive associations with non‐vascular dementia among men, which seemed driven by metals (hazard ratio ever high vs. background exposure: 1.35 [0.98–1.86]). Pesticide exposure showed statistically significant, inverse associations with non‐vascular dementia among men. We found no associations for shocks, aromatic solvents, and diesel motor exhaust.ConclusionsConsistent positive associations were found between occupational exposure to metals and non‐vascular dementia. The finding on pesticides is not supported in the overall literature. Am. J. Ind. Med. 58:625–635, 2015. © 2015 Wiley Periodicals, Inc.
Effect of electrospun fibers of polyhydroxybutyrate filled with different organoclays on morphology, biodegradation, and thermal stability of poly(ε‐caprolattone)
Authors: Marega Carla , Marigo Antonio 
Published: May 2015

ABSTRACTThe properties of nanocomposites of poly(ε‐caprolattone) (PCL) were studied, the pristine PCL was implemented with the introduction of electrospun fibers of polyhydroxybutyrate (PHB), containing a cationic (Cloisite) or an anionic (Perkalite) clay. These multicomponent composites containing a very low amount of clay confined in fibers are different from usual nanocomposite materials containing clay dispersed in the polymer matrix, which are produced by solvent casting or melt extrusion. To analyze the influence of the different fillers on the final composite, a preliminary study on PHB cast films and fibers prepared from the same solution was carried out, and then a thorough analysis was accomplished of the behavior of these particular nanocomposites PCL/PHB fibers/clay to elucidate the effects of the filled electrospun fibers on the PCL matrix. The structure and morphology of the samples were characterized by wide‐angle X‐ray diffraction and small angle X‐ray scattering; differential scanning calorimetry and thermogravimetric analysis were used to understand the influence of the fillers on the thermal behavior and stability; mechanical properties were evaluated and biodegradation studies were carried out. The PHB electrospun fibers and the fractured surface of the final composites were examined by scanning electron microscopy. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42342.
Fabrication of ordered microporous styrene‐acrylonitrile copolymer blend imprinted membranes for selective adsorption of phenol from salicylic acid using breath figure method
Authors: Sun Fengquan , Meng Minjia , Yan Li , He Zhihui , Yan Yongsheng , Liu Yan , Liu Shijuan 
Published: May 2015

ABSTRACTHighly selective, ordered microporous molecularly imprinted membranes (MIMs) for phenol were synthesized by breath figure (BF) method using styrene‐acrylonitrile copolymer (SAN) as the membrane matrix and molecularly imprinted polymer nanoparticles (nano‐MIPs) as the imprinted nanoparticles. The nano‐MIPs were synthesized by oil‐in‐water emulsion polymerization using 4‐vinyl pyridine (4‐VP), methyl methacrylate (MMA) or cinnamic acid (CA) as the functional monomer, respectively. The prepared nano‐MIPs were characterized by transmission electron microscope (TEM) and Raman, whereas MIMs were characterized by SEM, membrane flux, and selective adsorption experiments. Morphological analysis exhibited that the addition of nano‐MIPs improved the formation of ordered and well‐defined porous membrane morphology. Compared with MMA‐MIM and CA‐MIM, the 4‐VP‐MIM exhibited higher membrane flux, adsorption capacity, and stronger selective binding for phenol as well as excellent permeation selectivity for phenol. Moreover, the selective effect of 4‐VP‐MIM on phenol was strongly affected by the amount of 4‐VP imprinted nanoparticles (nano‐4‐VP‐MIPs). The experimental data revealed that the 4‐VP‐MIM containing 2.0 wt % of nano‐4‐VP‐MIPs exhibited the highest separation selectivity for the template phenol, whose selectivity coefficients for phenol relative to salicylic acid (SA) and p‐hydroxybenzoic acid (p‐HB) were 5.6770 and 5.5433, respectively, which was close to the predicted selectivity coefficient value. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42350.
Robust Finite‐Time Stability Control of a Class of High‐Order Uncertain Nonlinear Systems
Authors: Liu Haitao , Wang Xiaozhen , Zhang Tie 
Published: May 2015

AbstractIn this study, a novel robust finite‐time stability controller is proposed for a class of high‐order uncertain nonlinear systems. It uses the dynamic surface control (DSC) approach to simplify the traditional backstepping design for high‐order nonlinear systems, thus avoiding the “explosion of terms”. The finite‐time stability of the closed‐loop system is guaranteed to have high performance, such as fast transient and strong robustness to dynamic uncertainties, and the tracking error is made arbitrarily small. Simulation results of two examples indicate that the proposed controller is effective.
Finite‐Time Optimal Tracking Control for Dynamic Systems on Lie Groups
Authors: Liu Yongfang , Geng Zhiyong 
Published: May 2015

AbstractThis paper investigates the problem of finite‐time optimal tracking control for dynamic systems on Lie groups for the situation when the tracking time and/or the cost functions need to be considered. The specific results are illustrated on SE(3) (the specific Euclidean groups of rigid body motions). The tracking time is given according to task requirements in advance. By using Pontryagin's maximum principle (PMP) on Lie groups and the backstepping method, a finite‐time optimal tracking control law is designed to track a desired reference trajectory at the given time. Simultaneously, the corresponding cost functions are guaranteed to be optimal. Compared with existing results of optimal control on Lie groups, it is noteworthy that we consider the finite‐time tracking control for dynamic systems rather than kinematic systems. Furthermore, the obtained optimal control law is described by explicit formulations, which is significant for practical applications.
Investigation of protein selectivity in multimodal chromatography using in silico designed Fab fragment variants
Authors: Karkov Hanne Sophie , Krogh Berit Olsen , Woo James , Parimal Siddharth , Ahmadian Haleh , Cramer Steven M. 
Published: May 2015

ABSTRACTIn this study, a unique set of antibody Fab fragments was designed in silico and produced to examine the relationship between protein surface properties and selectivity in multimodal chromatographic systems. We hypothesized that multimodal ligands containing both hydrophobic and charged moieties would interact strongly with protein surface regions where charged groups and hydrophobic patches were in close spatial proximity. Protein surface property characterization tools were employed to identify the potential multimodal ligand binding regions on the Fab fragment of a humanized antibody and to evaluate the impact of mutations on surface charge and hydrophobicity. Twenty Fab variants were generated by site‐directed mutagenesis, recombinant expression, and affinity purification. Column gradient experiments were carried out with the Fab variants in multimodal, cation‐exchange, and hydrophobic interaction chromatographic systems. The results clearly indicated that selectivity in the multimodal system was different from the other chromatographic modes examined. Column retention data for the reduced charge Fab variants identified a binding site comprising light chain CDR1 as the main electrostatic interaction site for the multimodal and cation‐exchange ligands. Furthermore, the multimodal ligand binding was enhanced by additional hydrophobic contributions as evident from the results obtained with hydrophobic Fab variants. The use of in silico protein surface property analyses combined with molecular biology techniques, protein expression, and chromatographic evaluations represents a previously undescribed and powerful approach for investigating multimodal selectivity with complex biomolecules. Biotechnol. Bioeng. 2015;112: 2305–2315. © 2015 Wiley Periodicals, Inc.
Unveiling of novel regio‐selective fatty acid double bond hydratases from Lactobacillus acidophilus involved in the selective oxyfunctionalization of mono‐ and di‐hydroxy fatty acids
Authors: Kim Kyoung‐Rok , Oh Hye‐Jin , Park Chul‐Soon , Hong Seung‐Hye , Park Ji‐Young , Oh Deok‐Kun 
Published: May 2015

ABSTRACTThe aim of this study is the first time demonstration of cis‐12 regio‐selective linoleate double‐bond hydratase. Hydroxylation of fatty acids, abundant feedstock in nature, is an emerging alternative route for many petroleum replaceable products thorough hydroxy fatty acids, carboxylic acids, and lactones. However, chemical route for selective hydroxylation is still quite challenging owing to low selectivity and many environmental concerns. Hydroxylation of fatty acids by hydroxy fatty acid forming enzymes is an important route for selective biocatalytic oxyfunctionalization of fatty acids. Therefore, novel fatty acid hydroxylation enzymes should be discovered. The two hydratase genes of Lactobacillus acidophilus were identified by genomic analysis, and the expressed two recombinant hydratases were identified as cis‐9 and cis‐12 double‐bond selective linoleate hydratases by in vitro functional validation, including the identification of products and the determination of regio‐selectivity, substrate specificity, and kinetic parameters. The two different linoleate hydratases were the involved enzymes in the 10,13‐dihydroxyoctadecanoic acid biosynthesis. Linoleate 13‐hydratase (LHT‐13) selectively converted 10 mM linoleic acid to 13S‐hydroxy‐9(Z)‐octadecenoic acid with high titer (8.1 mM) and yield (81%). Our study will expand knowledge for microbial fatty acid‐hydroxylation enzymes and facilitate the designed production of the regio‐selective hydroxy fatty acids for useful chemicals from polyunsaturated fatty acid feedstocks. Biotechnol. Bioeng. 2015;112: 2206–2213. © 2015 Wiley Periodicals, Inc.
A simple LC‐MS/MS method for quantitative analysis of underivatized neurotransmitters in rats urine: assay development, validation and application in the CUMS rat model
Authors: Zhai Xue‐jia , Chen Fen , Zhu Chao‐ran , Lu Yong‐ning 
Published: May 2015

AbstractMany amino acid neurotransmitters in urine are associated with chronic stress as well as major depressive disorders. To better understand depression, an analytical LC‐MS/MS method for the simultaneous determination of 11 underivatized neurotransmitters (4‐aminohippurate, 5‐HIAA, glutamate, glutamine, hippurate, pimelate, proline, tryptophan, tyramine, tyrosine and valine) in a single analytical run was developed. The advantage of this method is the simple preparation in that there is no need to deconjugate the urine samples. The quantification range was 25–12,800 ng mL−1 with >85.8% recovery for all analytes. The nocturnal urine concentrations of the 11 neurotransmitters in chronic unpredictable mild stress (CUMS) model rats and control group (n = 12) were analyzed. A series of significant changes in urinary excretion of neurotransmitters could be detected: the urinary glutamate, glutamine, hippurate and tyramine concentrations were significantly lower in the CUMS group. In addition, the urinary concentrations of tryptophan as well as tyrosine were significantly higher in chronically stressed rats. This method allows the assessment of the neurotransmitters associated with CUMS in rat urine in a single analytical run, making it suitable for implementation as a routine technique in depression research. Copyright © 2015 John Wiley & Sons, Ltd.
DNA Three‐Way Junctions Stabilized by Hydrophobic Interactions for Creation of Functional Nanostructures
Authors: Laing Brian M. , Juliano Rudolph L. 
Published: May 2015

AbstractThe construction of nanomaterials from oligonucleotides by modular assembly invariably requires the use of branched nucleic acid architectures such as three‐ and four‐way junctions (3WJ and 4WJ). We describe the stabilization of DNA 3WJ by using non‐nucleotide lipophilic spacers to create a hydrophobic pocket within the junction space. Stabilization of nucleic acid junctions is of particular importance when constructing nanostructures in the “ultra‐nano” size range (<20 nm) with shorter double‐stranded regions. UV thermal melting studies show that lipophilic spacers strategically placed within the junction space significantly increased thermal stability. For a 3WJ with eight base pair arms, thermal stability was increased from 30.5 °C for the unmodified junction to a maximum stability of 55.0 °C. The stability of the junction can be modulated within this temperature range by using the appropriate combinations of spacers.
Helicase‐Dependent Isothermal Amplification of DNA and RNA by Using Self‐Avoiding Molecular Recognition Systems
Authors: Yang Zunyi , McLendon Chris , Hutter Daniel , Bradley Kevin M. , Hoshika Shuichi , Frye Carole B. , Benner Steven A. 
Published: May 2015

AbstractAssays that detect DNA or RNA (xNA) are highly sensitive, as small amounts of xNA can be amplified by PCR. Unfortunately, PCR is inconvenient in low‐resource environments, and requires equipment and power that might not be available in these environments. Isothermal procedures, which avoid thermal cycling, are often confounded by primer dimers, off‐target priming, and other artifacts. Here, we show how a “self avoiding molecular recognition system” (SAMRS) eliminates these artifacts and gives clean amplicons in a helicase‐dependent isothermal amplification (SAMRS‐HDA). We also show that incorporating SAMRS into the 3′‐ends of primers facilitates the design and screening of primers for HDA assays. Finally, we show that SAMRS‐HDA can be twofold multiplexed, difficult to achieve with HDA using standard primers. Thus, SAMRS‐HDA is a more versatile approach than standard HDA, with a broader applicability for xNA‐targeted diagnostics and research.
Prognostic value of aortic root calcification volume on clinical outcomes after transcatheter balloon‐expandable aortic valve implantation
Authors: Watanabe Yusuke , Lefèvre Thierry , Bouvier Erik , Arai Takahide , Hayashida Kentaro , Chevalier Bernard , Romano Mauro , Hovasse Thomas , Garot Philippe , Donzeau‐Gouge Patrick , Farge Arnaud , Cormier Bertrand , Morice Marie‐Claude 
Published: May 2015

BackgroundFew data are available about whether aortic root calcification may impact the outcomes after transcatheter aortic valve implantation (TAVI).ObjectivesThis study sought to evaluate the impact of aortic root calcification volume on clinical outcome after TAVI with balloon expandable Edwards Sapien XT valve (Edwards Lifesciences, Irvine, California).MethodsA total of 162 TAVI patients (aged 84.0 [Interquartile Range (IQR) 81.0–84.0] years, Logistic EuroSCORE 14.5 [IQR 9.8–25.1]) with preprocedural MDCT were studied. Aortic root calcification volume was measured by MDCT image and using the dedicated software for aortic valve assessment (the automated 3mensioTM Valves 5.1, sp1, 3mensio Pie Medical Imaging BV, Maastricht, the Netherlands). A valve calcification index (VCI) was defined as calcification volume (mm3)/body surface area (mm2).ResultsVCI was significantly higher among patients with 30‐day mortality. A VCI threshold of 517.4 (area under the curve 0.69, 95% CI 0.50–0.87, P = 0.03) predicted a higher incidence of annulus rupture (9.1 vs. 0.9%, P = 0.02) and cardiac tamponade (12.7 vs. 1.9%, P < 0.01), lower device success (83.6% vs. 95.3%, P < 0.01) and 30‐day survival rate (80.0% vs. 97.2%, P < 0.01). Multivariate logistic regression analysis showed only ejection fraction and VCI were identified as independent predictors of 30‐day mortality (Odds ratio 0.948 [95% confidence interval 0.909–0.988], P = 0.012, Odds ratio 1.003 [95% confidence interval 1.001–1.005], P = 0.013, respectively).ConclusionsSignificantly worse acute clinical outcomes after Edwards valve implantation were observed in patients with large amount of aortic annulus calcifications quantitatively measured by dedicated MDCT software. Application of VCI may prove helpful in prediction of clinical outcomes after TAVI. © 2015 Wiley Periodicals, Inc.