bluuebunny/crossref_metadata_2025_split huggingface dataset:
Windblown dust influenced by conventional and undercutter tillage within the Columbia Plateau, USA
Authors: Sharratt B. S. , Feng G. 
Published: June 2009

AbstractExceedance of the US Environmental Protection Agency national ambient air quality standard for PM10 (particulate matter ≤10 µm in aerodynamic diameter) within the Columbia Plateau region of the Pacific Northwest US is largely caused by wind erosion of agricultural lands managed in a winter wheat–summer fallow rotation. Land management practices, therefore, are sought that will reduce erosion and PM10 emissions during the summer fallow phase of the rotation. Horizontal soil flux and PM10 concentrations above adjacent field plots (>2 ha), with plots subject to conventional or undercutter tillage during summer fallow, were measured using creep and saltation/suspension collectors and PM10 samplers installed at various heights above the soil surface. After wheat harvest in 2004 and 2005, the plots were either disked (conventional) or undercut with wide sweeps (undercutter) the following spring and then periodically rodweeded prior to sowing wheat in late summer. Soil erosion from the fallow plots was measured during six sampling periods over two years; erosion or PM10 loss was not observed during two periods due to the presence of a crust on the soil surface. For the remaining sampling periods, total surface soil loss from conventional and undercutter tillage ranged from 3 to 40 g m–2 and 1 to 27 g m–2 while PM10 loss from conventional and undercutter tillage ranged from 0·2 to 5·0 g m–2 and 0·1 to 3·3 g m–2, respectively. Undercutter tillage resulted in a 15% to 65% reduction in soil loss and 30% to 70% reduction in PM10 loss as compared with conventional tillage at our field sites. Therefore, based on our results at two sites over two years, undercutter tillage appears to be an effective management practice to reduce dust emissions from agricultural land subject to a winter wheat–summer fallow rotation within the Columbia Plateau. Copyright © 2009 John Wiley & Sons, Ltd.
Relapse rates with long‐term antidepressant drug therapy: a meta‐analysis
Authors: Williams Nolan , Simpson Annie N. , Simpson Kit , Nahas Ziad 
Published: June 2009

AbstractBackgroundSeveral long‐term double‐blind placebo controlled trials have shown prophylactic antidepressant therapy in unipolar depression. The goal of this work was to conduct a meta‐analysis that would incorporate the most recent trials and evaluate their overall level of efficacy and relapse prevention over time.MethodsWe performed a comprehensive literature search. The extracted data from selected studies were used to construct a regression model and evaluate the effect of treatment, time on medication, severity of illness, age, gender, and number of previous episodes.ResultsAcross 11 maintenance treatment studies, the relapse rate was significantly different at 1 year for active drug (23%) versus placebo (51%). In addition, time on medication significantly affected the relapse rate.ConclusionProphylactic antidepressant drug therapy appears efficacious in preventing future relapses across a range of illness severity as well as age. More studies are needed to explore the effects of various acute antidepressant strategies and the direct influence of treatment resistance on relapse outcomes. Copyright © 2009 John Wiley & Sons, Ltd.
A test for multimodality of regression derivatives with application to nonparametric growth regressions
Authors: Henderson Daniel J. 
Published: June 2009

AbstractThis paper presents a method to test for multimodality of an estimated kernel density of derivative estimates from a nonparametric regression. The test is included in a study of nonparametric growth regressions. The results show that in the estimation of unconditional β‐convergence the distribution of the partial effects is multimodal, with one mode in the negative region (primarily OECD economies) and possibly two modes in the positive region (primarily non‐OECD economies) of the estimates. The results for conditional β‐convergence show that the density is predominantly negative and there is mixed evidence that the distribution is unimodal. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of glycerol triacetate using functionalized ionic liquid as catalyst
Authors: Li Lu , Yu Shi‐Tao , Xie Cong‐Xia , Liu Fu‐Sheng , Li Hong‐Juan 
Published: June 2009

AbstractBACKGROUND: With the development of bio‐diesel, it has become an urgent task to make full use of glycerol, which is a by‐product of the production of bio‐diesel. Glycerol triacetate (GTA) is one of the important derivatives of glycerol and can be used in many fields. Usually it is prepared industrially in the presence of mineral acidic catalysts. The shortcomings of such a process include serious environmental issues, complicated technique and no recyclability of catalyst. Recently, it was reported that many acidic functionalized ionic liquids (FILs) could be synthesized and used in esterifications with excellent catalytic performance. Hence, the esterification of glycerol with acetic acid to produce GTA was investigated using acidic FILs as catalyst.RESULTS: The results indicated that [HSO3‐pmim][HSO4] exhibited promising catalytic performance. Using [HSO3‐pmim][HSO4] as catalyst, the yield of GTA was above 95%. The catalyst was utilized ten times and the GTA yield remained above 91%.CONCLUSION: The good catalytic performance and reusability of this FIL may contribute to the development of an environmentally friendly strategy for the synthesis of GTA. Copyright © 2009 Society of Chemical Industry
Molecular dynamics simulations reveal the disparity in specific recognition of GCC‐box by AtERFs transcription factors super family in Arabidopsis
Authors: Wang Shichen , Yang Shuo , Yin Yuejia , Xi Jinghui , Li Shanyu , Hao Dongyun 
Published: June 2009

AbstractArabidopsis ethylene responsive element binding factors (AtERFs) form a transcription factor super family. While the functions of most AtERFs are unknown, a number of AtERFs appear to be involved in regulation of stress‐related genes through their DNA binding domains (DBD), namely ERF domains, which recognize a consensus motif GCC‐box at the regulatory region. In this study, molecular dynamics simulations were performed on the four ERF domain‐GCC‐box complexes, AtERF1, AtERF4, AtEBP and CFBF1, to determine disparity in specific binding to the GCC‐box by the AtERFs. Our results suggested that three amino acid residues Arg29, Glu39 and Arg41, played a vital role in direct readout of DNA. The position of the consensus sequence GCCGCC has an intrinsic disparity on binding with ERF domains. The third C, fourth G and the last C in the GCC motif was compulsory for recognition by ERF domains. Our results provide structural evidence for a sequence‐dependent recognition mechanism for AtERFs. Copyright © 2009 John Wiley & Sons, Ltd.
MALDI‐TOF mass spectrometry of hordeins: rapid approach for identification of malting barley varieties
Authors: Šalplachta Jiří , Bobálová Janette 
Published: June 2009

AbstractA procedure for identification of malting barley varieties using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) of ethanol‐soluble barley proteins (hordeins) is described. The hordeins were first extracted from milled barley grains by several extraction protocols (using different extraction agents and conditions). Hordein extracts were then analyzed directly via MALDI‐TOF MS without any preliminary purification or separation step, and the protein profiles of analyzed hordein extracts were compared in order to find out the most suitable extraction procedure for mass spectrometric analysis. The optimized procedure was successfully applied to identification of 13 malting barley varieties. Our results revealed that the proposed mass spectrometry‐based approach provides characteristic mass patterns of extracted hordeins, which can be advantageously used for barley variety identification. Copyright © 2009 John Wiley & Sons, Ltd.
Selective detection of phosphatidylethanol homologues in blood as biomarkers for alcohol consumption by LC‐ESI‐MS/MS
Authors: Gnann H. , Weinmann W. , Engelmann C. , Wurst F. M. , Skopp G. , Winkler M. , Thierauf A. , Auwärter V. , Dresen S. , Bouzas N. Ferreirós 
Published: June 2009

AbstractA new validated method for the quantitation of the abnormal phospholipid phosphatidylethanol (PEth)—a biomarker for ethanol uptake—has been developed by LC‐ESI‐MS/MS following miniaturised organic solvent extraction and reversed phase chromatography with phosphatidylbutanol (PBut) as internal standard. PEth homologues with two fatty acid substituents—PEth 18 : 1/18 : 1, PEth 16 : 0/16 : 0—were determined in post‐mortem blood collected from heavy drinkers at autopsy and also in whole blood samples from a volunteer after a single 60 g‐dose of ethanol. Furthermore, PEth 18 : 1/16 : 0 or its isobaric isomer PEth—16 : 0/18 : 1 was detected. In comparison to previous high‐performance liquid chromatography (HPLC) methods with evaporative light scattering detection (ELSD), the LC‐MS/MS‐method is more sensitive—with a limit of detection below 20 ng/ml—and more selective for single PEth homologues, while ELSD has been used for detection of the sum of PEth homologues with approximately 10 times less sensitivity. LC‐MS/MS enables monitoring of PEth homologues as biomarkers for harmful and prolonged alcohol consumption as with HPLC/ELSD earlier, where PEth is measurable in blood only after more than 50 g ethanol daily intake for more than 2 weeks. Because of its higher sensitivity, there is a potential to detect single heavy drinking by LC‐MS/MS, when PEth is formed in very low concentrations. This opens a new field of application of PEth to uncover single or multiple heavy drinking at a lower frequency and with a larger window of detection in blood than before by HPLC/ELSD or by use of other direct markers, e.g. ethyl glucuronide or ethyl sulfate. Copyright © 2009 John Wiley & Sons, Ltd.
Surface‐enhanced Raman spectroscopy of indanthrone and flavanthrone
Authors: Chang Jingjing , Cañamares Maria Vega , Aydin Metin , Vetter Wilfried , Schreiner Manfred , Xu Weiqing , Lombardi John R. 
Published: June 2009

AbstractThe normal Raman and surface‐enhanced Raman scattering (SERS) spectra of flavanthrone and indanthrone were obtained at several excitation wavelengths. The spectral assignments were aided by density functional calculations. Since both molecules have very high symmetry (C2h) including a center of inversion, we expect that the modes of u symmetry will be forbidden in the normal Raman spectrum. However, proximity to the surface causes special SERS enhancement of several of the bu modes, along with somewhat weaker enhancement of the au and bg modes. Copyright © 2009 John Wiley & Sons, Ltd.
DFT, FT‐Raman, FT‐IR and NMR studies of 2‐fluorophenylboronic acid
Authors: Erdogdu Yusuf , Tahir Güllüoǧlu M. , Kurt Mustafa 
Published: June 2009

AbstractThe experimental and theoretical vibrational spectra of 2‐fluorophenylboronic acid (2fpba) were studied. The Fourier transform Raman and Fourier transform infrared spectra of the 2fpba molecule were recorded in the solid phase. The structural and spectroscopic analysis of the molecule was carried out by using Hartree‐Fock and density functional harmonic calculations. For the title molecule, only one form was found to be the most stable structure, by using B3LYP level with the 6‐31++G(d,p) basis set. Selected experimental bands were assigned and characterized on the basis of the scaled theoretical wavenumbers by their total energy distribution (TED). The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the 2fpba molecule were calculated using the Gauge‐Invariant‐ atomic orbital (GIAO) method in DMSO solution using IEF‐PCM model and compared with the experimental data. Finally, geometric parameters, vibrational wavenumbers and chemical shifts were compared with available experimental data of the molecule. Copyright © 2009 John Wiley & Sons, Ltd.
The mechanism of the recrystallization process in epitaxial GaN under dynamic stress field: atomistic origin of planar defect formation
Authors: Das C. R. , Dhara S. , Hsu H. C. , Chen L. C. , Jeng Y. R. , Bhaduri A. K. , Raj Baldev , Chen K. H. , Albert S. K. 
Published: June 2009

AbstractThe mechanism of the recrystallization in epitaxial (0001) GaN film, introduced by the indentation technique, is probed by lattice dynamic studies using Raman spectroscopy. The recrystallized region is identified by micro‐Raman area mapping. ‘Pop‐in’ bursts in loading lines indicate nucleation of dislocations and climb of dislocations. These processes set in plastic motion of lattice atoms under stress field at the center of indentation for the initiation of the recrystallization process. A planar defect migration mechanism is evolved. A pivotal role of vacancy migration is noted, for the first time, as the rate‐limiting factor for the dislocation dynamics initiating the recrystallization process in GaN. Copyright © 2009 John Wiley & Sons, Ltd.
The suppression of MAD1 by AKT‐mediated phosphorylation activates MAD1 target genes transcription
Authors: Chou Chao‐Kai , Lee Dung‐Fang , Sun Hui‐Lung , Li Long‐Yuan , Lin Chun‐Yi , Huang Wei‐Chien , Hsu Jung‐Mao , Kuo Hsu‐Ping , Yamaguchi Hirohito , Wang Ying‐Nai , Liu Mo , Wu Hsin‐Yi , Liao Pao‐Chi , Yen Chia‐Jui , Hung Mien‐Chie 
Published: June 2009

AbstractMAX dimerization protein 1 (MAD1) is a transcription suppressor that antagonizes MYC‐mediated transcription activation, and the inhibition mechanism occurs mainly through the competition of target genes' promoter MYC binding sites by MAD1. The promoter binding proteins switch between MYC and MAD1 affects cell proliferation and differentiation. However, little is known about MAD1's regulation process in cancer cells. Here, we present evidence that AKT inhibits MAD1‐mediated transcription repression by physical interaction with and phosphorylation of MAD1. Phosphorylation reduces the binding affinity between MAD1 and its target genes' promoter and thereby abolishes its transcription suppression function. Mutation of the phosphorylation site from serine to alanine rescues the DNA‐binding ability in the presence of activated AKT. In addition, AKT inhibits MAD1‐mediated target genes (hTERT and ODC) transcription repression and promotes cell cycle and cell growth. However, mutated S145A MAD1 abrogates the inhibition by AKT. Thus, our results suggest that phosphorylation of MAD1 by AKT inhibits MAD1‐mediated transcription suppression and subsequently activates the transcription of MAD1 target genes. © 2009 Wiley‐Liss, Inc.
Cellular dichotomy between anchorage‐independent growth responses to bFGF and TPA reflects molecular switch in commitment to carcinogenesis
Authors: Waters Katrina M. , Tan Ruimin , Opresko Lee K. , Quesenberry Ryan D. , Bandyopadhyay Somnath , Chrisler William B. , Weber Thomas J. 
Published: June 2009

AbstractWe have investigated gene expression patterns underlying reversible and irreversible anchorage‐independent growth (AIG) phenotypes to identify more sensitive markers of cell transformation for studies directed at interrogating carcinogenesis responses. In JB6 mouse epidermal cells, basic fibroblast growth factor (bFGF) induces an unusually efficient and reversible AIG response, relative to 12‐O‐tetradecanoyl phorbol‐13‐acetate (TPA)‐induced AIG which is irreversible. The reversible and irreversible AIG phenotypes are characterized by largely nonoverlapping global gene expression profiles. However, a subset of differentially expressed genes were identified as common to reversible and irreversible AIG phenotypes, including genes regulated in a reciprocal fashion. Hepatic leukemia factor (HLF) and D‐site albumin promoter‐binding protein (DBP) were increased in both bFGF and TPA soft agar colonies and selected for functional validation. Ectopic expression of human HLF and DBP in JB6 cells resulted in a marked increase in TPA‐ and bFGF‐regulated AIG responses. HLF and DBP expression were increased in soft agar colonies arising from JB6 cells exposed to gamma radiation and in a human basal cell carcinoma tumor tissue, relative to paired nontumor tissue. Subsequent biological network analysis suggests that many of the differentially expressed genes that are common to bFGF‐ and TPA‐dependent AIG are regulated by c‐Myc, SP‐1, and HNF‐4 transcription factors. Collectively, we have identified a potential molecular switch that mediates the transition from reversible to irreversible AIG. © 2009 Wiley‐Liss, Inc.
Direct saturation MRI: Theory and application to imaging brain iron
Authors: Smith Seth A. , Bulte Jeff W.M. , van Zijl Peter C.M. 
Published: June 2009

AbstractWhen applying RF saturation to tissue, MRI signal reductions occur due to magnetization transfer (MT) and direct saturation (DS) effects on water protons. It is shown that the direct effects, often considered a nuisance, can be used to distinguish gray matter (GM) regions with different iron content. DS effects were selected by reducing the magnitude and duration of RF irradiation to minimize confounding MT effects. Contrary to MT saturation spectra, direct water saturation spectra are characterized by a symmetric Lorentzian‐shaped frequency dependence that can be described by an exact analytical solution of the Bloch equations. The effect of increased transverse relaxation, e.g., due to the presence of iron, will broaden this saturation spectrum. As a first application, DS ratio (DSR) images were acquired to visualize GM structures in the human brain. Similar to T2*‐weighted images, the quality of DSR images was affected by local field inhomogeneity, but this could be easily corrected for by centering the saturation spectrum on a voxel‐by‐voxel basis. The results show that, contrary to commonly used T2*‐weighted and absolute R2 images, the DSR images visualize all GM structures, including cortex. A direct correlation between DSR and iron content was confirmed for these structures. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Automatic quality assessment in structural brain magnetic resonance imaging
Authors: Mortamet Bénédicte , Bernstein Matt A. , Jack Clifford R. , Gunter Jeffrey L. , Ward Chadwick , Britson Paula J. , Meuli Reto , Thiran Jean‐Philippe , Krueger Gunnar 
Published: June 2009

AbstractMRI has evolved into an important diagnostic technique in medical imaging. However, reliability of the derived diagnosis can be degraded by artifacts, which challenge both radiologists and automatic computer‐aided diagnosis. This work proposes a fully‐automatic method for measuring image quality of three‐dimensional (3D) structural MRI. Quality measures are derived by analyzing the air background of magnitude images and are capable of detecting image degradation from several sources, including bulk motion, residual magnetization from incomplete spoiling, blurring, and ghosting. The method has been validated on 749 3D T1‐weighted 1.5T and 3T head scans acquired at 36 Alzheimer's Disease Neuroimaging Initiative (ADNI) study sites operating with various software and hardware combinations. Results are compared against qualitative grades assigned by the ADNI quality control center (taken as the reference standard). The derived quality indices are independent of the MRI system used and agree with the reference standard quality ratings with high sensitivity and specificity (>85%). The proposed procedures for quality assessment could be of great value for both research and routine clinical imaging. It could greatly improve workflow through its ability to rule out the need for a repeat scan while the patient is still in the magnet bore. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Toward true 3D visualization of active catheters using compressed sensing
Authors: Schirra C.O. , Weiss S. , Krueger S. , Pedersen S.F. , Razavi R. , Schaeffter T. , Kozerke S. 
Published: June 2009

AbstractA crucial requirement in MR‐guided interventions is the visualization of catheter devices in real time. However, true 3D visualization of the full length of catheters has hitherto been impossible given scan time constraints. Compressed sensing (CS) has recently been proposed as a method to accelerate MR imaging of sparse objects. Images acquired with active interventional devices exhibit a high CNR and are inherently sparse, therefore rendering CS ideally suited for accelerating data acquisition. A framework for true visualization of active catheters in 3D is proposed employing CS to gain high undersampling factors making real‐time applications feasible. Constraints are introduced taking into account prior knowledge of catheter geometry and catheter motion over time to improve and accelerate image reconstruction. The potential of the method is demonstrated using computer simulations and phantom experiments and in vivo feasibility is demonstrated in a pig experiment. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Cerebral activation by fasting induces lactate accumulation in the hypothalamus
Authors: Violante Inês R. , Anastasovska Jelena , Sanchez‐Canon Gina J. , Rodrigues Tiago B. , Righi Valeria , Nieto‐Charques Laura , Parkinson James R.C. , Bloom Stephen R. , Bell Jimmy D. , Cerdán Sebastián 
Published: June 2009

AbstractCarbon‐13 (13C) high‐resolution magic angle spinning (HR‐MAS) spectroscopy was used to investigate the neuroglial coupling mechanisms underlying appetite regulation in the brain of C57BL/6J mice metabolizing [1‐13C]glucose. Control fed or overnight fasted mice received [1‐13C]glucose (20 μmol/g intraperitoneally [i.p.]), 15 min prior to brain fixation by focused microwaves. The hypothalamic region was dissected from the rest of the brain and 13C HR‐MAS spectra were obtained from both biopsies. Fasting resulted in a significant increase in hypothalamic [3‐13C]lactate and [2‐13C]γ‐aminobutyric acid (GABA) relative to the remaining brain. Administration of the orexigenic peptide ghrelin (0.3 nmol/g i.p.) did not increase hypothalamic [3‐13C]lactate or [2‐13C]GABA, suggesting that ghrelin signaling is not sufficient to elicit all the metabolic consequences of hypothalamic activation by fasting. Our results indicate that the hypothalamic regulation of appetite involves, in addition to the well‐known neuropeptide signaling, increased neuroglial lactate shuttling and augmented GABA concentrations. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.
Robust estimation of spatially variable noise fields
Authors: Landman Bennett A. , Bazin Pierre‐Louis , Smith Seth A. , Prince Jerry L. 
Published: June 2009

AbstractConsideration of spatially variable noise fields is becoming increasingly necessary in MRI given recent innovations in artifact identification and statistically driven image processing. Fast imaging methods enable study of difficult anatomical targets and improve image quality but also increase the spatial variability in the noise field. Traditional analysis techniques have either assumed that the noise is constant across the field of view (or region of interest) or have relied on separate MRI acquisitions to measure the noise field. These methods are either inappropriate for many modern scanning protocols or are overly time‐consuming for already lengthy scanning sessions. We propose a new, general framework for estimating spatially variable noise fields from related, but independent MR scans that we call noise field equivalent scans. These heuristic analyses enable robust noise field estimation in the presence of artifacts. Generalization of noise estimators based on uniform regions, difference images, and maximum likelihood are presented and compared with the estimators derived from the proposed framework. Simulations of diffusion tensor imaging and T2‐relaxometry demonstrate a 10‐fold reduction in mean squared error in noise field estimation, and these improvements are shown to be robust to artifact contamination. In vivo studies show that spatially variable noise fields can be readily estimated with typical data acquired at 1.5T. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.