bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rational Design of Sterically and Electronically Easily Tunable Chiral Bisimidazolines and Their Applications in Dual Lewis Acid/Brønsted Base Catalysis for Highly Enantioselective Nitroaldol (Henry) Reactions
Authors: Ma Kuoyan , You Jingsong 
Published: November 2006

AbstractA new addition to the rational design of sterically and electrically easily tunable chiral bis(imidazoline) ligands from chiral amino alcohols has been developed. Vast structural variation of chiral bis(imidazoline) ligands can be simply achieved by the choice of both the 1,2‐amino alcohol and its N‐1 R1 substituent. A small library of chiral bisimidazolines (1 a–h) has been constructed. The method has provided an easy and simplified route to a diverse set of air‐stable and water‐tolerant chiral bis(imidazoline) ligands on 10 g scales. The dual Lewis Acid/Brønsted base catalytic system generated from the (S)‐1 a/Cu(OTf)2 complex and Et3N was able to catalyze Henry reactions between aldehydes and nitromethane effectively at room temperature, and also to tolerate a wide scope of aldehydes with excellent enantiomeric excesses. Not only aromatic aldehydes but also aliphatic aldehydes afforded the nitroalcohol products, with enantiomeric excesses in the 93–98 % range. This dual catalytic system is among the most effective systems so far reported for the asymmetric parent Henry reactions. This work also represents the first members of the class of chiral bisimidazolines to have been demonstrated to achieve excellent enantioselectivities.
Actin deficiency induces cofilin phosphorylation: Proteome analysis of HeLa cells after β‐actin gene silencing
Authors: Liu Ning , Academia Katrina , Rubio Teresa , Wehr Tim , Yeck Todd , Jordan Liz , Hamby Keith , Paulus Aran 
Published: November 2006

AbstractActin‐binding proteins regulate the dynamic structure and function of actin filaments in the cell. Much is known about how manipulation of the actin‐binding proteins affects the structure and function of actin filaments; however, little is known about how manipulation of actin in the cell affects actin‐binding proteins. We addressed this question by utilizing two technologies: RNA interference and 2‐dimensional gel electrophoresis. We knocked down β‐actin expression in HeLa cells using short interfering RNA and applied 2‐DGE to examine alterations in the HeLa cell proteome. We revealed a 2–5 fold increases of four protein spots on 2‐D gels and identified these proteins by mass spectrometry. Three of the four proteins were actin‐binding proteins, including cofilin, which promotes both disassembly and assembly of actin filaments but becomes inactivated when phosphorylated. Further examination revealed that the cofilin total protein level barely increased, but the phosphorylated cofilin level increased dramatically in HeLa cells after β‐actin siRNA treatment. These results suggest that in response to siRNA‐induced β‐actin deficiency HeLa cells inactivate cofilin by phosphorylation rather than down‐regulate its protein expression level. This study also demonstrates that the combination of RNA interference and 2‐dimensional gel electrophoresis technologies provides a valuable method to study protein interactions in a specific cellular pathway. Cell Motil. Cytoskeleton 2006. © 2006 Wiley‐Liss, Inc.
Survival and toxicity differences between 5‐day and weekly cisplatin in patients with locally advanced cervical cancer
Authors: Einstein Mark H. , Novetsky Akiva P. , Garg Madhur , Hailpern Susan M. , Huang Gloria S. , Glueck Arielle , Fields Abbie L. , Kalnicki Shalom , Goldberg Gary L. 
Published: November 2006

AbstractBACKGROUND.Cisplatin (CDDP) administration concomitant with radiotherapy (RT) for the treatment of locally advanced cervical cancer has evolved from an inpatient 5‐day every 21‐day regimen to a weekly outpatient regimen. This study was designed to test for differences in progression‐free survival (PFS) and toxicity between the 2 regimens.METHODS.In all, 77 consecutive patients at a single institution with stage IB2‐IV cervical cancer were included in this analysis (using the International Federation of Gynecologists and Obstetricians staging system). All patients were treated with CDDP, external beam RT, and 2 9‐Gy high‐dose‐rate brachytherapy treatments. Two cohorts were compared: 1) 5‐day, patients treated from 1995 to 2001 with CDDP 20 mg/m2 × 5 days every 21 days concomitant with RT; 2) weekly, treated after May 2001 with CDDP 40 mg/m2 weekly concomitant with RT.RESULTS.In all, 50 patients were treated with the 5‐day regimen and 27 patients with the weekly regimen. There were no significant demographic differences between the groups. Overall 3‐year PFS, controlling for stage, was 90% and 76% for 5‐day and weekly groups, respectively (P = .01). Adjusting for stage, age, and completion of treatment, the risk of treatment failure among the weekly group was 3.46 times higher than the 5‐day group (P = .02). The weekly group had a 3.43 times higher risk of developing acute toxicities than the 5‐day group (P = .02) in advanced‐stage patients.CONCLUSIONS.Patients who received weekly CDDP have a shorter 3‐year PFS. Patients with advanced‐stage cervical cancer who received weekly CDDP had significantly more acute toxicities. These data should be confirmed in a multiinstitutional, randomized, controlled study. Cancer 2007. © 2006 American Cancer Society.
Differential mRNA distribution of components of the ERK/MAPK signalling cascade in the adult mouse brain
Authors: Di Benedetto Barbara , Hitz Christiane , Hölter Sabine M. , Kühn Ralf , Vogt Weisenhorn Daniela M. , Wurst Wolfgang 
Published: November 2006

AbstractThe mitogen‐activated protein kinases (MAPKs), also called extracellular signal‐regulated kinases (ERKs), are a group of serine/threonine terminal protein kinases activated downstream of a pleiotrophy of transmembrane receptors. Main intracellular components of the MAPK signalling pathway are the RAF, MEK, and ERK proteins, which work in a cascade of activator and effector proteins. They regulate many fundamental cellular functions, including cell proliferation, cell survival, and cell differentiation by transducing extracellular signals to cytoplasmic and nuclear effectors. To reveal more details about possible activation cascades in this pathway, the present study gives a complete description of the differential expression of Braf, Mek1, Mek2, Mek5, Erk1, Erk2, Erk3, and Erk5 in the adult murine brain by way of in situ hybridization analysis. In this study, we found that each gene is widely expressed in the whole brain, except for Mek2, but each displays a very distinct expression pattern, leading to distinct interactions of the MAPK components within different regions. Most notably we found that 1) Braf and Erk3 are coexpressed in the hippocampus proper, confirming a possible functional interaction; 2) in most forebrain areas, Mek5 and Erk5 are coexpressed; and 3) in the neurogenic regions of the brain, namely, the olfactory bulb and the dentate gyrus, Braf is absent, indicating that other activator proteins have to take over its function. Despite these differences, our results show widespread coexpression of the pathway components, thereby confirming the hypothesis of redundant functions among several MEK and ERK proteins in some regions of the brain. J. Comp. Neurol. 500:542–556, 2007. © 2006 Wiley‐Liss, Inc.
Crystal Structure, Solid‐State NMR Spectroscopic and Photoluminescence Studies of Organic‐Inorganic Hybrid Materials (HL)6[Ge6(OH)6(hedp)6]·2(L)·H2O, L = hqn or phen (Eur. J. Inorg. Chem. 23/2006)
Authors: Mafra Luís , Almeida Paz Filipe E. , Shi Fa‐Nian , Sá Ferreira Rute A. , Carlos Luís D. , Trindade Tito , Fernandez Christian , Klinowski Jacek , Rocha João 
Published: November 2006

AbstractThe cover picture shows the three‐dimensional supramolecular arrangement of 1,10‐phenanthroline (phen) residues in compound (Hphen)6[Ge6(OH)6(hedp)6]·2(phen)·20H2O (where H4hedp stands for etidronic acid). Protonated organic residues, Hphen+, π‐π‐stack along the [101] direction of the unit cell, which leads to the formation of columns that are interconnected through a series of weak C–H···π interactions with neighbouring 1,10‐phenanthrolines. The resulting organic framework is highly porous and contains charge‐balancing centrosymmetric hexameric anionic [Ge6(ν2‐OH)6(C2H4O7P2)6]6– moieties within the channels and a large number of highly disordered water molecules (total available volume of ca. 2462 Å3 per unit cell). Details are discussed in the article by J. Rocha et al. on p. 4741 ff.
MCMC‐based linkage analysis for complex traits on general pedigrees: multipoint analysis with a two‐locus model and a polygenic component
Authors: Sung Yun Ju , Thompson Elizabeth A. , Wijsman Ellen M. 
Published: November 2006

AbstractWe describe a new program lm_twoqtl, part of the MORGAN package, for parametric linkage analysis with a quantitative trait locus (QTL) model having one or two QTLs and a polygenic component, which models additional familial correlation from other unlinked QTLs. The program has no restriction on number of markers or complexity of pedigrees, facilitating use of more complex models with general pedigrees. This is the first available program that can handle a model with both two QTLs and a polygenic component. Competing programs use only simpler models: one QTL, one QTL plus a polygenic component, or variance components (VC). Use of simple models when they are incorrect, as for complex traits that are influenced by multiple genes, can bias estimates of QTL location or reduce power to detect linkage. We compute the likelihood with Markov Chain Monte Carlo (MCMC) realization of segregation indicators at the hypothesized QTL locations conditional on marker data, summation over phased multilocus genotypes of founders, and peeling of the polygenic component. Simulated examples, with various sized pedigrees, show that two‐QTL analysis correctly identifies the location of both QTLs, even when they are closely linked, whereas other analyses, including the VC approach, fail to identify the location of QTLs with modest contribution. Our examples illustrate the advantage of parametric linkage analysis with two QTLs, which provides higher power for linkage detection and better localization than use of simpler models. Genet. Epidemiol. © 2006 Wiley‐Liss, Inc.
Cordectomy by CO2 laser or radiotherapy for small T1a glottic carcinomas: Costs, local control, survival, quality of life, and voice quality
Authors: Goor Kim M. , Peeters A. Jeanne G. E. , Mahieu Hans F. , Langendijk Johannes A. , Leemans C. René , Verdonck‐de Leeuw Irma M. , van Agthoven Michel 
Published: November 2006

AbstractBackground.The clinical results of radiotherapy and endoscopic cordectomy for T1a glottic carcinoma are reported to be similar, but costs of both treatments may differ. Therefore, we retrospectively evaluated the costs, voice quality, quality of life, and clinical results of both treatments.Methods.Costs and effects from the first visit up to 2 years of follow‐up were calculated, based on chart data of 35 and 54 patients who were treated with curative intent for T1a glottic carcinoma from 1995 to 1999 with radiotherapy and endoscopic cordectomy, respectively. Voice quality and quality of life were evaluated by means of patient questionnaires.Results.Total costs (in Euros) of radiotherapy and CO2‐laser cordectomy were €8322 and €4434, respectively, including the costs of treating possible recurrences. The effects of both treatments were equal, including voice quality and quality of life.Conclusions.We conclude that endoscopic cordectomy is an efficient alternative for radiotherapy for these patients. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
The use of a linkage analysis as evidence in the conviction of the Newcastle serial murderer, South Africa
Authors: Labuschagne G&eacute;rard N. 
Published: November 2006

AbstractThe linking of a series of crimes to one individual has always been problematic, especially in the absence of eyewitness or forensic evidence. During the investigation, another means whereby this can be done is through linkage analysis. Yet a linkage analysis can also play a role during the trial of a serial offender. This paper examines the use of a linkage analysis report as evidence during the trial of the Newcastle serial murderer in South Africa. The linkage analysis examined the circumstances of the crime, modus operandi, and signature behaviour of the offender, to come to the conclusion that all the offences were committed by one individual, despite the lack of eyewitness or forensic evidence linking the suspect to two of the four incidents. This evidence was admitted by the court and the presiding officer concurred that the accused was guilty of committing the crimes during the third and fourth incidents. Copyright © 2006 John Wiley & Sons, Ltd.
Infrared and Raman spectroscopic studies of L‐valinium picrate
Authors: Senthilkumar S. , Briget Mary M. , Ramakrishnan V. 
Published: November 2006

AbstractThe vibrational assignments of the observed wavenumbers have been made by analyzing the infrared and Raman spectra of L‐valinium picrate in the crystalline state at room temperature. L‐Valinium acts as the cation of the crystal and the carbonyl CO group exists in the protonated form in it. Asymmetric deformation and symmetric deformation modes of the isopropyl group have been identified, indicating that the two CH3 groups are in different environments. The stretching and bending modes of the various functional groups have been shifted owing to the extensive intermolecular hydrogen bonding in the crystal. The symmetry of the picrate anion has not been modified in the crystal by the hydrogen bonding with the cation. Fermi resonance is also observed. Copyright © 2006 John Wiley & Sons, Ltd.
Comparison between prospective and retrospective triggering for mouse cardiac MRI
Authors: Heijman Edwin , de Graaf Wolter , Niessen Petra , Nauerth Arno , van Eys Guillaume , de Graaf Larry , Nicolay Klaas , Strijkers Gustav J. 
Published: November 2006

AbstractHigh‐resolution magnetic resonance imaging (MRI) has evolved into one of the major non‐invasive tools to study the healthy and diseased mouse heart. This study presents a Cartesian CINE MRI protocol based on a fast low‐angle shot sequence with a navigator echo to generate cardiac triggering and respiratory gating signals retrospectively, making the use of ECG leads and respiratory motion sensors obsolete. MRI of the in vivo mouse heart using this sequence resulted in CINE images with no detectable cardiac and respiratory motion artefacts. The retrospective method allows for steady‐state imaging of the mouse heart, which is essential for quantitative contrast‐enhanced MRI studies. A comparison was made between prospective and retrospective methods in terms of the signal‐to‐noise ratio and the contrast‐to‐noise ratio between blood and myocardial wall, as well as global cardiac functional indices: end‐diastolic volume, end‐systolic volume, stroke volume and ejection fraction. The retrospective method resulted in almost constant left‐ventricle wall signal intensity throughout the cardiac cycle, at the expense of a decrease in the signal‐to‐noise ratio and the contrast‐to‐noise ratio between blood and myocardial wall as compared with the prospective method. Prospective and retrospective sequences yielded comparable global cardiac functional indices. The largest mean relative difference found was 8% for the end‐systolic volume. Copyright © 2006 John Wiley & Sons, Ltd.
Strain effects during coherent spin transport via moving quantum dots
Authors: Stotz J. A. H. , Santos P. V. , Hey R. , Ploog K. H. 
Published: November 2006

AbstractThe geometry of the sample is shown to dictate the importance of strain on the spin‐orbit splitting of the conduction band for electrons transported via dynamic quantum dots (DQDs) generated by surface acoustic waves (SAWs). Photoluminescence measurements monitoring the Larmor precession of electron spins in the absence of an applied magnetic field are used to characterize the spin‐orbit splitting of the conduction band. We show that, in thick quantum wells (QWs), the Dresselhaus spin‐orbit contribution to the precession frequency reduces and may become comparable to the one associated with the strain field induced by the SAW. We attribute deviations in the measured precession frequency to strain effects, which become more pronounced for QWs located closer to the surface because of the larger SAW strain field. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Laplace DLTS studies on deep levels coexisted with InAs quantum dots
Authors: Lin S. W. , Peaker A. R. , Song A. M. 
Published: November 2006

AbstractSelf‐assembled InAs/GaAs quantum dot structures have been investigated in both conventional and Laplace‐transform deep‐level transient spectroscopy (DLTS) experiments. Laplace DLTS technique provides orders of magnitude better energy resolution than conventional DLTS and hence enables us to study the electronic fine structure of the deep level states that are revealed using the conventional DLTS method. Two well‐separated peaks corresponding to excitation energies of 468 meV and 485 meV are determined in the quantum dot sample, which have energy broadenings of 13.7 meV and 22.9 meV, respectively. A fine structure is also observed in the reference sample, but the ratio between the two peaks differs and the energy broadening is too narrow to be resolved even by the Laplace DLTS. The strain relaxation due to the QD formation is proposed to explain our observations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Emission at 1.55 µm from InAs/GaAs quantum dots grown by metal organic chemical vapor deposition via antimony incorporation
Authors: Guimard Denis , Tsukamoto Shiro , Nishioka Masao , Arakawa Yasuhiko 
Published: November 2006

AbstractBy introducing antimony during the growth of InAs/GaAs quantum dots (QDs) by metalorganic chemical vapor deposition, we have achieved ground‐state emission at 1.55 µm (and beyond) from InAs/GaAs QDs capped by an In0.24Ga0.76As strain‐reducing layer (SRL) at room temperature (RT). We show that antimony irradiation results in the formation of QD sub‐ensembles. Photoluminescence intensity is strongly enhanced (×100) at RT compared to Sb‐free QDs capped by higher In‐content SRL in which ground‐state emission saturates at wavelengths shorter than 1.51 µm. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phonon‐induced electron relaxation in correlated quantum dots
Authors: Climente Juan I. , Bertoni Andrea , Rontani Massimo , Goldoni Guido , Molinari Elisa 
Published: November 2006

AbstractWe study the electron momentum relaxation in single and vertically coupled quantum dots due to coupling with acoustic phonons. We consider both the single‐electron and the few‐electron regimes, using a Full Configuration Interaction approach to account for the electron‐electron repulsion. Our findings suggest that electronic correlations tend to reduce intradot and interdot transition rates. We also show that external magnetic fields acting on properly designed quantum dots may strongly suppress electron‐phonon coupling. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Power dependent photoluminescence of lateral quantum dot molecules: Indication of extended electron states
Authors: v. Lippen T. , Nötzel R. , Eijkemans T. J. , Bogaart E. W. , Wolter J. H. 
Published: November 2006

AbstractExcitation power density dependent photoluminescence (PL) measurements of an ensemble of ordered lateral quantum dot (QD) molecules containing on average 4 and 8 QDs are carried out. Asymmetric broadening of the PL spectra is observed with increasing excitation power density which is stronger for 8 QDs per molecule than for 4 QDs. In addition, a shift of the PL peak to higher energies occurs. In p‐type modulation‐doped QD molecules the asymmetric broadening and high‐energy shift are enhanced. N‐type modulation‐doped QD molecules exhibit a square‐shaped PL spectrum, resembling that of modulation‐doped quantum wells. These findings are consistently explained by state filling in the presence of extended electron states due to lateral electronic coupling of the QDs within the molecules forming a quasi two‐dimensional density of states. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical characterisation of single InAs quantum dots on GaAs substrate emitting at 1.3 μm
Authors: Chauvin N. , Baira M. , Bru‐Chevallier C. , Ilahi B. , Sfaxi L. , Maaref H. 
Published: November 2006

AbstractSingle InAs/GaAs quantum dots are studied using micro‐photoluminescence spectroscopy. Single dot spectroscopy shows an antibinding biexciton. Some of these quantum dots are laterally coupled due to an anisotropic dot repartition. At low excitation power density, four excitons emissions are observed and are interpreted as the four possible exciton recombinations of two coupled quantum dots. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of ribosomal proteins as biomarkers for matrix‐assisted laser desorption/ionization mass spectral identification of Lactobacillus plantarum
Authors: Sun Liwei , Teramoto Kanae , Sato Hiroaki , Torimura Masaki , Tao Hiroaki , Shintani Tomoyoshi 
Published: November 2006

AbstractFor rapid identification of bacteria by matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS), a bioinformatics approach using ribosomal subunit proteins as biomarkers has been proposed. This method compares the observed masses for biomarkers with calculated masses as predicted from the amino acid sequences registered on protein databases. To evaluate this approach, the expressed ribosomal proteins of a genome‐sequenced bacterium, Lactobacillus plantarum NCIMB 8826, were characterized as a model sample. The protein expression of 42 ribosomal subunit proteins, together with 10 ribosome‐associated proteins in the isolated ribosome fraction, was confirmed through two‐dimensional gel electrophoresis combined with peptide mass fingerprinting. The observed masses of the proteins in the isolated ribosome fraction were then determined by MALDI‐MS. We preliminarily selected 44 biomarkers whose observed masses were matched with the calculated masses predicted from the amino acid sequence registered in the protein databases by considering N‐terminal methionine loss only. Of these, the finally selected reliable biomarkers were 34 proteins including 31 ribosomal subunit proteins and 3 ribosome‐associated proteins that could be observed in the MALDI mass spectra of the cell lysate sample. These biomarkers were usable in MALDI‐MS characterization of two industrial L. plantarum cultures. Copyright © 2006 John Wiley & Sons, Ltd.
Determining barriers to sustainability within the Costa Rican coffee industry
Authors: Adams M. A. , Ghaly A. E. 
Published: November 2006

AbstractThe Costa Rican coffee industry has been the subject of many sustainability plans, all of which have had a particular bias towards one aspect of sustainability or another. Following the sustainability evaluation framework discussed in previous work a significant gap was recognized between the requirements of a sustainable industry, which address all facets of sustainability (including all stakeholders – both producers and processors), and the present system. This was particularly so within aspects of institutional considerations and the lack of continuity when integrating processing considerations into sustainability considerations. The concerns, deficiencies and perceptions of the various stakeholders within the industry were documented in order to ensure a proper match between sustainability barriers and any steps that would be taken to address them. The inclusion of stakeholders' thoughts and perceptions was determined to be important in the establishment of any policy aimed at improving the overall sustainability of the coffee industry. Using the sustainability framework as the foundation for discussion, specific barriers to the application of sustainability were highlighted and discussed. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.