bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dust attenuation in starburst galaxies determined by measuring the dependence of the optical color indices on galaxy inclination
Authors: Vince O. 
Published: July 2010

AbstractWe use optical color indices (colors) from the SDSS database to study the effect of dust in starburst galaxies by mea‐suring the dependence of colors on galaxy inclination. Starburst galaxies with ongoing star formation, are rich with metals/dust and are, therefore, an excellent objects for studying the effect of dust in galaxies. They are selected using the [O III]λ 5007/Hα vs. [N II]λ 6584/Hβ diagram, that is, the BPT‐diagram. We use Kauffmann's empirical demarcation line in the BPT‐diagram to exclude galaxies with active galactic nuclei (AGN) from the sample because they have different physical and dust properties from normal galaxies. The sample is divided into bins according to galaxy stellar mass and 4000 Å break (which is a coarse measure of a galaxy star formation history; SFH) and the reddening with inclination is studied as a function of these two physical parameters. Assuming that the dust effect is negligible in the SDSS z ‐band, we derive the attenuation curves for these galaxies. We fit the attenuation curves with a simple power law and use power law index to interpret the relative distribution of dust and stars in the starburst galaxies (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sulphur abundances in halo stars from multiplet 3 at 1045 nm
Authors: Caffau E. , Sbordone L. , Ludwig H.‐G. , Bonifacio P. , Spite M. 
Published: July 2010

AbstractSulphur is a volatile α ‐element which is not locked into dust grains in the interstellar medium (ISM). Hence, its abundance does not need to be corrected for dust depletion when comparing the ISM to the stellar atmospheres. The abundance of sulphur in the photosphere of metal‐poor stars is a matter of debate: according to some authors, [S/Fe] versus [Fe/H] forms a plateau at low metallicity, while, according to other studies, there is a large scatter or perhaps a bimodal distribution. In metal‐poor stars sulphur is detectable by its lines of multiplet 1 at 920 nm, but this range is heavily contaminated by telluric absorptions, and one line of the multiplet is blended by the hydrogen Paschen ζ line. We study the possibility of using multiplet 3 (at 1045 nm) for deriving the sulphur abundance because this range, now observable at the VLT with the infra‐red spectrograph CRIRES, is little contaminated by telluric absorption and not affected by blends at least in metal‐poor stars. We compare the abundances derived from multiplets 1 and 3, taking into account NLTE corrections and 3D effects. Here we present the results for a sample of four stars, although the scatter is less pronounced than in previous analysis, we cannot find a plateau in [S/Fe], and confirm the scatter of the sulphur abundance at low metallicity (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimization of ultrasound contrast agents with computational models to improve selection of ligands and binding strength
Authors: Maul Timothy M. , Dudgeon Drew D. , Beste Michael T. , Hammer Daniel A. , Lazo John S. , Villanueva Flordeliza S. , Wagner William R. 
Published: July 2010

AbstractDiagnosis of cardiovascular disease is currently limited by the testing modality. Serum tests for biomarkers can provide quantification of severity but lack the ability to localize the source of the cardiovascular disease, while imaging technology such as angiography and ultrasound can only determine areas of reduced flow but not the severity of tissue ischemia. Targeted imaging with ultrasound contrast agents offers the ability to locally image as well as determine the degree of ischemia by utilizing agents that will cause the contrast agent to home to the affected tissue. Ultrasound molecular imaging via targeted microbubbles (MB) is currently limited by its sensitivity to molecular markers of disease relative to other techniques (e.g., radiolabeling). We hypothesize that computational modeling may provide a useful first approach to maximize microbubble binding by defining key parameters governing adhesion. Adhesive dynamics (AD) was used to simulate the fluid dynamic and stochastic molecular binding of microbubbles to inflamed endothelial cells. Sialyl LewisX (sLex), P‐selectin aptamer (PSA), and ICAM‐1 antibody (abICAM) were modeled as the targeting receptors on the microbubble surface in both single‐ and dual‐targeted arrangements. Microbubble properties (radius [Rc], kinetics [kf, kr], and densities of targeting receptors) and the physical environment (shear rate and target ligand densities) were modeled. The kinetics for sLex and PSA were measured with surface plasmon resonance. Rc, shear rate, and densities of sLex, PSA, or abICAM were varied independently to assess model sensitivity. Firm adhesion was defined as MB velocity <2% of the free stream velocity. AD simulations revealed an optimal microbubble radius of 1–2 µm and thresholds for $k_{{\rm f}}^{{\rm in}} $ (>102 s−1) and $k_{{\rm r}}^{{\rm o}} $ (<10−3 s−1) for firm adhesion in a multi‐targeted system. State diagrams for multi‐targeted microbubbles suggest sLex and abICAM microbubbles may require 10‐fold more ligand to achieve firm adhesion at higher shear rates than sLex and PSA microbubbles. The AD model gives useful insight into the key parameters for stable microbubble binding, and may allow flexible, prospective design, and optimization of microbubbles to enhance clinical translation of ultrasound molecular imaging. Biotechnol. Bioeng. 2010;107: 854–864. © 2010 Wiley Periodicals, Inc.
Long-term results of surgery for lithium-associated hyperparathyroidism
Authors: Järhult J , Ander S , Asking B , Jansson S , Meehan A , Kristoffersson A , Nordenström J 
Published: July 2010

Abstract

Background
Lithium therapy for affective bipolar disease is frequently associated with hyperparathyroidism (HPT), but the results of surgical treatment are virtually unknown. The aim of this retrospective review was to analyse the long-term outcome after surgery for lithium-induced HPT in a large series of patients.

Methods
Seventy-one patients on chronic lithium therapy who underwent surgery in three university and three district hospitals in Sweden were followed for a median of 6·3 years. Histopathology, complications of surgery and normocalcaemia at 6 months after surgery and last follow-up were analysed.

Results
The primary histopathological diagnoses were adenoma (45 per cent), double adenomas (3 per cent) and hyperplasia (52 per cent). No permanent paresis of the recurrent laryngeal nerve was recorded but 13 per cent of the patients suffered from permanent hypoparathyroidism. At follow-up, the rate of persistent and recurrent HPT was 42 per cent regardless of the histopathological diagnosis.

Conclusion
The results of conventional surgery for lithium-associated HPT are poor. The surgical approach should be adjusted for the multiglandular disease that is usually the cause of HPT in patients on chronic lithium therapy.
The effectiveness and experiences of blended learning approaches to computer programming education
Authors: Deperlioglu Omer , Kose Utku 
Published: July 2010

AbstractAt the nexus of education and technology, blended learning is growing rapidly. Integrating face‐to‐face and online learning, blending can enhance learning and optimize seat time. This paper describes the use of the blended e‐learning model in a course “Data Structures and Algorithms” given at the Afyon Kocatepe University, Turkey. This model is realized as a combination of a face‐to‐face environment and online learning, using the University's Learning Management System (LMS) named @KU‐UZEM. The LMS consists of many applications in accordance with SCORM standards, such as, student records, user roles, courses, exams security applications, student affairs, counseling services, internal communication, director processes and evaluation. It provides whole software infrastructure by a virtual academic institution and is currently used in Afyon Kocatepe University. This paper describes both the technology for course design and programme redesign adopted a blended learning approach with both face‐to‐face and online learning aimed at enhancing the students' control over their own learning. According to the obtained results with the performed experimental evaluation, the realized blended learning model provided more effective and efficient educational experience rather than traditional, face‐to‐face learning. A survey conducted at the end of the course also showed that students were satisfied with the pedagogical approach, and their academic achievements were also better than expected. Particularly important is that the dropout rate was greatly diminished, which could be related to students' satisfaction with the support they received from the teacher and the system. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 328–342, 2013
Green Catalytic Baeyer–Villiger Oxidation with Hydrogen Peroxide in Water Mediated by PtII Catalysts
Authors: Cavarzan Alessandra , Scarso Alessandro , Sgarbossa Paolo , Michelin Rino A. , Strukul Giorgio 
Published: July 2010

AbstractBaeyer–Villiger oxidation of cyclic ketones with 35 % hydrogen peroxide as a green oxidant mediated by monomeric PtII complexes bearing alkyl diphosphines greatly benefits from the employment of water with anionic surfactants as reaction medium. Under such conditions, the reaction shows enhanced catalytic activity compared to that with organic solvents. For more acid sensitive substrates, hydrolysis of the lactone product to the corresponding hydroxy acid occurs. Mild experimental conditions, such as moderate temperature and low catalyst loading (≤2 % mol), enabled moderate to good yields.
A General Route to Fully Terminally tert‐Butylated Linear Polyenes
Authors: Klein Dagmar , Kiliçkiran Pinar , Mlynek Cornelia , Hopf Henning , Dix Ina , Jones Peter G. 
Published: July 2010

AbstractStarting from the readily available α,β‐unsaturated ketone, 3‐tert‐butyl‐4,4‐dimethyl‐2‐pentenal, higher vinylogues, and fully terminally tert‐butylated polyolefins with up to 13 consecutive conjugated double bonds have been prepared by either McMurry dimerization or Wittig chain‐elongation routes. The highly unsaturated conjugated π systems, which show a remarkable stability, have been characterized by spectroscopic methods and, in many cases, by X‐ray structural analysis. The yields are high enough to allow for thorough chemical reactivity studies.
Structure–Function Relationships in Liquid‐Crystalline Halogen‐Bonded Complexes
Authors: Bruce Duncan W. , Metrangolo Pierangelo , Meyer Franck , Pilati Tullio , Präsang Carsten , Resnati Giuseppe , Terraneo Giancarlo , Wainwright Stephen G. , Whitwood Adrian C. 
Published: July 2010

AbstractNew liquid‐crystalline materials were prepared by self‐assembly driven by halogen bonding between a range of 4‐alkoxystilbazoles, 4‐alkyl‐, and 4‐alkoxy‐substituted pyridines as halogen‐bonding acceptors, and substituted derivatives of 4‐iodotetrafluorophenyl as halogen‐bonding donors. Despite the fact that the starting materials are not mesomorphic, the dimeric, halogen‐bonded complexes obtained exhibited nematic and SmA phases, depending on the length of the alkyl chains present on the components. The modularity of this approach also led to new chiral mesogens starting from non‐mesomorphic chiral compounds.
Asymmetric CC Bond‐Formation Reaction with Pd: How to Favor Heterogeneous or Homogeneous Catalysis?
Authors: Reimann Sven , Grunwaldt Jan‐Dierk , Mallat Tamas , Baiker Alfons 
Published: July 2010

AbstractThe enantioselective allylic alkylation of (E)‐1,3‐diphenylallyl acetate was studied to clarify the heterogeneous or homogeneous character of the Pd/Al2O3(R)‐BINAP catalyst system. A combined approach was applied: the catalytic tests were completed with in situ XANES measurements to follow the oxidation state of Pd as a function of the reaction conditions. The study revealed that the oxidized Pd (after exposure to ambient air) is efficiently reduced by the solvents THF and dioxane, and by the nucleophile sodium dimethyl malonate, and thus these conditions prevent Pd leaching. The chiral modifier BINAP plays a dual role: a considerable coverage of the Pd surface by the bulky compound slows down the initial reduction of the surface oxides but BINAP itself may consume surface oxygen (through its conversion to BINAPO and BINAPO2) and contribute to the maintenance of the active metal surface during the reaction. Carrying out the reaction under pressure in an inert gas atmosphere is important to minimize the oxygen diffusion into the reaction mixture and to avoid leaching. The (known) effect of temperature is critical as well: our catalyst system is inactive at room temperature, which is a clear deviation from the behavior of the corresponding homogeneous system. In contrast, halogenated solvents are easily dehalogenated on Pd/Al2O3 and thus they favor leaching of the metal and formation of soluble compounds, analogous to classical metal corrosion in the presence of halide ions. The frequently observed dissolution of Pd in the presence of halogenated substrates may be explained similarly.
High‐Speed Living Polymerization of Polar Vinyl Monomers by Self‐Healing Silylium Catalysts
Authors: Zhang Yuetao , Lay Frank , García‐García Pilar , List Benjamin , Chen Eugene Y.‐X. 
Published: July 2010

AbstractThis contribution describes the development and demonstration of the ambient‐temperature, high‐speed living polymerization of polar vinyl monomers (M) with a low silylium catalyst loading (≤ 0.05 mol % relative to M). The catalyst is generated in situ by protonation of a trialkylsilyl ketene acetal (RSKA) initiator (I) with a strong Brønsted acid. The living character of the polymerization system has been demonstrated by several key lines of evidence, including the observed linear growth of the chain length as a function of monomer conversion at a given [M]/[I] ratio, near‐precise polymer number‐average molecular weight (Mn, controlled by the [M]/[I] ratio) with narrow molecular weight distributions (MWD), absence of an induction period and chain‐termination reactions (as revealed by kinetics), readily achievable chain extension, and the successful synthesis of well‐defined block copolymers. Fundamental steps of activation, initiation, propagation, and catalyst “self‐repair” involved in this living polymerization system have been elucidated, chiefly featuring a propagation “catalysis” cycle consisting of a rate‐limiting CC bond formation step and fast release of the silylium catalyst to the incoming monomer. Effects of acid activator, catalyst and monomer structure, and reaction temperature on polymerization characteristics have also been examined. Among the three strong acids incorporating a weakly coordinating borate or a chiral disulfonimide anion, the oxonium acid [H(Et2O)2]+[B(C6F5)4]− is the most effective activator, which spontaneously delivers the most active R3Si+, reaching a high catalyst turn‐over frequency (TOF) of 6.0×103 h−1 for methyl methacrylate polymerization by Me3Si+ or an exceptionally high TOF of 2.4×105 h−1 for n‐butyl acrylate polymerization by iBu3Si+, in addition to its high (>90 %) to quantitative efficiencies and a high degree of control over Mn and MWD (1.07–1.12). An intriguing catalyst “self‐repair” feature has also been demonstrated for the current living polymerization system.
Study on the Historical Distribution of Metals in Aquatic Sediments
Authors: Barreto Wagner José , Ishikawa Dílson Norio , Nicolau Andressa Clara , Magalhães Evandro Domingues , Inoue Fabiana , Nora Paulo dos Santos , Funfas Rodolfo , Barreto Sônia Regina Giancoli 
Published: July 2010

AbstractIn this study, the historical distribution of metals, phosphorous, and sulfur at four different depths in the sediments of different lakes formed in the course of an urban river (in Londrina, Parana State, Brazil) were determined. The transport of metals along the course of the river was observed mainly for Mn, Cr, and Zn. High concentrations of Pb in the Capivara Bay and Cr in the river were attributed to contamination from a battery plant and a tannery, respectively. The concentrations of heavy metals in the deepest layers of the sediments remain high several years after deposition.
Dynamic range expansion of receiver by using optimized gain adjustment for high‐field MRI
Authors: Oh C.H. , Ryu Y.C. , Hyun J.H. , Bae S.H. , Chung S.T. , Park H.W. , Kim Y.G. 
Published: July 2010

AbstractIn high‐field magnetic resonance imaging (MRI) system, the signal‐to‐noise ratio of MR signal is so high that the receiver frequently cannot cover the full dynamic range of the MR signal. Although this problem can be overcome by using a compander (compressor and expander) composed of logarithmic amplifiers and a ROM table to retrieve the nonlinearity of the logarithmic amplifiers or by simply increasing the number of bits of analog‐to‐digital converter, the methods can be costly and complex or even impossible for most commercial systems. In addition, the spectrometer has to be specifically designed to operate in those modes. In this article, we developed a simple dynamic range improvement method using a receiver with optimized variable gain control in which function can be implemented without any hardware modification to the spectrometer, if the spectrometer can do gain control during a scan. Simulations as well as experiments for the brain and resolution phantom have been performed, and the results demonstrate the utility of the proposed method. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part A 36A: 243–254, 2010.
Head and neck cancer
Authors: Rezende Taia Maria Berto , Freire Mirna de Souza , Franco Octávio Luiz 
Published: July 2010

AbstractTumors of the head and neck comprise an important neoplasia group, the incidence of which is increasing in many parts of the world. Recent advances in diagnostic and therapeutic techniques for these lesions have yielded novel molecular targets, uncovered signal pathway dominance, and advanced early cancer detection. Proteomics is a powerful tool for investigating the distribution of proteins and small molecules within biological systems through the analysis of different types of samples. The proteomic profiles of different types of cancer have been studied, and this has provided remarkable advances in cancer understanding. This review covers recent advances for head and neck cancer; it encompasses the risk factors, pathogenesis, proteomic tools that can help in understanding cancer, and new proteomic findings in this type of cancer. Cancer 2010. © 2010 American Cancer Society.
Change in fibroblast growth factor 2 expression as an early phase radiotherapy‐responsive marker in sequential biopsy samples from patients with cervical cancer during fractionated radiotherapy
Authors: Nakawatari Miyako , Iwakawa Mayumi , Ohno Tatsuya , Kato Shingo , Nakamura Etsuko , Ohkubo Yu , Tamaki Tomoaki , Imai Takashi 
Published: July 2010

AbstractBACKGROUND:The authors previously demonstrated that fibroblast growth factor 2 (FGF2) expression levels in tumor cells (FGF2‐T) may be an indicator of the efficacy of radiotherapy in patients with cervical cancer (CC). In the current study, this finding was extended in newly enrolled patients and was investigated further in stromal FGF2 (FGF2‐S) expression.METHODS:Sixty‐nine patients with CC were recruited as a validation set for the immunohistochemical detection of FGF2‐T from biopsy samples that were taken before (pretreatment) or 1 week after the initiation of radiotherapy (midtreatment). The authors also investigated the expression of FGF2 in tumor FGF2‐S and investigated vascular endothelial growth factor (VEGF), and cluster of differentiation 31 (CD31) (also called platelet endothelial cell adhesion molecule) in these patients and in an additional 35 patients from a previous study.RESULTS:FGF2 expression was detected in tumor cells from all patients and in stromal cells from 87% of patients. FGF2‐T was significantly higher in midtreatment samples (P = .0002), and a high ratio of midtreatment/pretreatment FGF2‐T was related significantly to a better prognosis (P = .025). Increased VEGF expression after the initiation of radiotherapy was related significantly to positive FGF2‐S in pretreatment samples (P = .035); however, it was not related to prognosis or microvessel density detected by CD31 expression.CONCLUSIONS:Radiation causes a response in tumor cells and adjacent normal cells and changes the extracellular matrix environment. In this study, the authors confirmed their previous findings and demonstrated that changes in FGF2‐T expression may be used as a marker to monitor the effectiveness of radiotherapy in patients with CC. These findings should improve patient selection for molecular targeted therapies, such as cytokine inhibitors, after standard‐of‐care treatment. Cancer 2010. © 2010 American Cancer Society.
Higher parity and shorter breastfeeding duration
Authors: Shinde Shivani S. , Forman Michele R. , Kuerer Henry M. , Yan Kai , Peintinger Florentia , Hunt Kelly K. , Hortobagyi Gabriel N. , Pusztai Lajos , Symmans W. Fraser 
Published: July 2010

AbstractBACKGROUND:The combination of increased parity and shorter breastfeeding duration might increase the odds of the least differentiated triple‐negative breast cancer (BC) phenotype, theoretically because an expanded progenitor cell population from each pregnancy would incompletely differentiate postpartum.METHODS:Subjects consisted of a consecutive case series of 2473 women treated for invasive breast cancer between 2001 and 2006. Breast cancer phenotype (triple‐negative BC, vs non–triple‐negative BC) was compared with reproductive and demographic information. Odds ratios (OR) with 95% confidence intervals (CIs) for the association of breastfeeding duration (months per child) and parity with triple‐negative BC were calculated after adjusting for ethnicity, age at menarche, family history, and age at diagnosis.RESULTS:Compared with non–triple‐negative BC, triple‐negative BC was associated with shorter duration of breastfeeding per child (OR, 0.93; 95% CI, 0.90‐0.97) and with higher parity (OR, 1.12; 95% CI, 1.06‐1.20). By using multivariate logistic regression, triple‐negative BC was independently associated with higher parity (OR, 2.76 [95% CI, 1.86‐4.08] if ≥3 live births; OR, 1.89 [95% CI, 1.30‐2.74] if ≤2 live births vs nulliparae), breastfeeding duration (OR, 0.55 [95% CI, 0.41‐0.74] if >2 mo/child and OR, 0.58 [95% CI, 0.42‐0.82] if ≤2 mo/child vs none), African American ethnicity (OR, 2.10; 95% CI, 1.52‐2.92), and younger age at diagnosis (OR, 3.02 [95% CI, 2.03‐4.47] if ≤40 years vs >60 years).CONCLUSIONS:Among women with invasive breast cancer, higher parity and the absence or short duration of breastfeeding were independently associated with triple‐negative BC. Any duration of breastfeeding was found to be associated with lower probability of triple‐negative BC, and the odds of this phenotype decreased with increasing duration of breastfeeding. Cancer 2010. © 2010 American Cancer Society.