bluuebunny/crossref_metadata_2025 huggingface dataset:
The best performance of spiral wired thermal diffusion columns of the frazier scheme
Authors: Yeh Ho‐Ming
Published: May 2010

Equations have been derived for the optimum wire angles of inclination for maximum separation, maximum production rate and minimum column height in the Frazier scheme of concentric‐tube thermal diffusion columns with a tight fitting wire spiral, having a diameter equal to the annular spacing, and wrapped on the entire inner tube. Considerable improvement in performance is obtained when a Frazier scheme is operated at the optimum corresponding wire angle of inclination, especially for the scheme of high column number.
Calculation of solubilities of the pesticides diuron and monuron in organic nonelectrolyte solvents using UNIFAC and modified UNIFAC (dortmund) models
Authors: Riverol Carmen , Hansen Henrik K. , Acree William
Published: May 2010

The solubility of diuron (3‐(3,4‐dichlorophenyl)‐1, 1 ‐dimethyl urea) and monuron (3‐(4‐chlorophenyl)‐1, 1 ‐dimethyl urea) in 49 and 43 different organic non‐electrolyte solvents, respectively, have been calculated. It was found that Modified UNIFAC described well the solubilities both in polar solvents like alcohols, ketones, esters and ethers and in nonpolar solvents like alkanes and aromatic hydrocarbons. UNIFAC and the mobile order theory supplement each other well in calculating the solubilities, which means that one can choose the right model depending on the solvent one is using.
Metronidazole–Deoxybenzoin Derivatives as Anti‐Helicobacter pylori Agents with Potent Inhibitory Activity against HPE‐Induced Interleukin‐8
Authors: Luo Yin , Li Huan‐Qiu , Zhou Yang , Li Zi‐Lin , Yan Tao , Zhu Hai‐Liang
Published: May 2010

A series of new metronidazole–deoxybenzoin derivatives were synthesized and evaluated for their antimicrobial activity against Helicobacter pylori. Highly selective anti‐H. pylori activity was also observed in synthesized compounds. Compound 34 exhibited the most potent activity, similar to the positive control amoxicillin. Furthermore, compounds 17 and 34 were able to significantly decrease H. pylori water extract (HPE)‐induced production of interleukin‐8 (IL‐8) in gastric mucosal cells, which did not show any effect on the cell viability.
Identification of accrual barriers onto breast cancer prevention clinical trials
Authors: Houlihan Robert H. , Kennedy Michael H. , Kulesher Robert R. , Lemon Stephenie C. , Wickerham D. Lawrence , Hsieh Chung‐Cheng , Altieri Dario C.
Published: May 2010

BACKGROUND:

The purpose of this study was to examine factors influencing a woman's decision to participate in a breast cancer prevention clinical trial. Nine healthcare organizations in Massachusetts cooperated in the present project.

METHODS:

The authors performed a case‐control study to compare responses between the study group (Study of Tamoxifen and Raloxifene [STAR] trial eligible, but not enrolled) and the control group (STAR trial participants) on 12 factors previously identified as barriers to accrual for clinical trials. Eight hypotheses were tested using multiple logistic regression to estimate the strength of the association for each factor on the dependent variable (study participation).

RESULTS:

The study samples were similar to the general population of eligible breast cancer prevention clinical trial subjects in the counties where the participating organizations were located, the state of Massachusetts, and nationally published STAR trial data. Results of a mailed questionnaire showed that when adjusting for subject demographics, and in the presence of other questions, 4 factors significantly influenced a woman's decision to enroll onto a breast cancer prevention clinical trial more than other eligible subjects: 1) clinician expertise and qualifications (P = .012; odds ratio [OR], 4.903; 95% confidence interval [CI], 1.41‐17.04); 2) personal desire to participate (P = .033; OR, 3.16; 95% CI, 1.10‐9.06); 3) perceived value of the trial (P = .020; OR, 2.92; 95% CI, 1.18‐7.21); and 4) level of trial inconvenience (P = .002; OR, 0.10; 95% CI, 0.02‐0.44).

CONCLUSIONS:

Addressing these issues in the relationship between patients and clinicians should improve accrual to breast cancer prevention clinical trials. Cancer 2010. © 2010 American Cancer Society.
p16INK4a is superior to high‐risk human papillomavirus testing in cervical cytology for the prediction of underlying high‐grade dysplasia
Authors: Samarawardana Panduka , Dehn Donna L. , Singh Meenakshi , Franquemont Douglas , Thompson Chesney , Gaido Loretta , Torkko Kathleen C. , Homer Petra , Burke Stephanie , Titmus Matthew A. , Nayi Vipul , Shroyer Kenneth R.
Published: May 2010

BACKGROUND

The primary goal of this study was to compare the clinical performance of an optimized and rigorously controlled immunocytochemical (ICC) assay for p16INK4a to high‐risk (HR) human papillomavirus (HPV) detection by polymerase chain reaction (PCR) as diagnostic adjuncts for cytology specimens from colposcopy patients.

METHODS:

The study included 403 cervical cytology specimens collected within 3 months of colposcopy. The colposcopic impression and cervical biopsy diagnosis served as the standards for correlation with cytological, p16INK4a, and HPV data. p16INK4a was evaluated using an immunoperoxidase‐based assay that was linear over 4 logs for the detection of HeLa‐spiked positive control cytology specimens, using a threshold for positive test results that was based on receiver operating characteristic curve analysis. HR‐HPV was detected by multiplex PCR using genotype‐specific primers.

RESULTS:

In all combined diagnostic categories (negative for intraepithelial lesion and malignancy, atypical glandular cells, atypical squamous cells of undetermined significance, atypical squamous cells cannot exclude high‐grade squamous intraepithelial lesion, low‐grade squamous intraepithelial lesion, and high‐grade squamous intraepithelial lesion), the p16INK4a ICC and HR‐HPV assays, respectively, had sensitivity of 81.7% and 83.3% (P = .81) and specificity of 78.1% and 50.9% (P < .001) for the detection of underlying ≥grade 2 cervical intraepithelial neoplasia (CIN) lesions on biopsy. Furthermore, the positive predictive value of p16INK4a ICC was greater than that of HR‐HPV for patients with biopsies ≥CIN‐2 (41.2% and 24.2%, respectively, P = .001).

CONCLUSIONS:

This p16INK4a immunocytochemical assay has superior specificity but similar sensitivity to HR‐HPV testing to predict underlying high‐grade dysplastic lesions in patients who are referred for colposcopy. The determination of the overall performance characteristics of p16INK4a immunocytochemistry, as an independent test or in combination with HPV testing in low‐risk screening populations, however, will require subsequent large‐scale prospective clinical trials. Cancer (Cancer Cytopathol) 2010. © 2010 American Cancer Society.
Comparison of high‐order absorbing boundary conditions and perfectly matched layers in the frequency domain
Authors: Rabinovich Daniel , Givoli Dan , Bécache Eliane
Published: May 2010

The need for numerical schemes for wave problems in large and unbounded domains appears in various applications, including modeling of pressure waves in arteries and other problems in biomedical engineering. Two powerful methods to handle such problems via domain truncation are the use of high‐order absorbing boundary conditions (ABCs) and perfectly matched layers (PMLs). A numerical study is presented to compare the performance of these two types of methods, for two‐dimensional problems governed by the Helmholtz equation. The high‐order ABCs employed here are of the Hagstrom–Warburton type; they are adapted and applied to the frequency domain for the first time. Four PMLs are examined, with linear, quadratic, constant and unbounded decay functions. Two planar configurations are considered: a waveguide and a quarter plane. In the latter case, special corner conditions are developed and used in conjunction with the ABC. One of the main conclusions from the ABC‐PML comparison is that in the high‐accuracy regime, the ABC scheme and the unbounded PML are equally effective. Copyright © 2010 John Wiley & Sons, Ltd.
Berezin transform in polynomial bergman spaces
Authors: Ameur Yacin , Makarov Nikolai , Hedenmalm Håkan
Published: May 2010

Fix a smooth weight function Q in the plane, subject to a growth condition from below. Let Km,n denote the reproducing kernel for the Hilbert space of analytic polynomials of degree at most n − 1 of finite L2‐norm with respect to the measure e−mQ dA. Here dA is normalized area measure, and m is a positive real scaling parameter. The (polynomial) Berezin measure
${\rm d}B_{m,n}^{\langle z_0\rangle}(z)=K_{m,n}(z_0,z_0)^{-1}|K_{m,n}(z,z_0)|^2{\rm e}^{-mQ(z)}\,{\rm d}A(z)$
for the point z0 is a probability measure that defines the (polynomial) Berezin transform

for continuous
$\font\open=msbm10 at 10pt\def\C{\hbox{\open C}}f\in L^\infty(\C)$. We analyze the semiclassical limit of the Berezin measure (and transform) as m → + ∞ while n = m τ + o(1), where τ is fixed, positive, and real. We find that the Berezin measure for z0 converges weak‐star to the unit point mass at the point z0 provided that Δ Q(z0) > 0 and that z0 is contained in the interior of a compact set ${\cal S}_\tau$, defined as the coincidence set for an obstacle problem. As a refinement, we show that the appropriate local blowup of the Berezin measure converges to the standardized Gaussian measure in the plane. For points $\font\open=msbm10 at 10pt\def\C{\hbox{\open C}}z_0\in \C\setminus{\cal S}_\tau$, the Berezin measure cannot converge to the point mass at z0. In the model case Q(z) = |z|2, when ${\cal S}_\tau$
is a closed disk, we find that the Berezin measure instead converges to harmonic measure at z0 relative to $\font\open=msbm10 at 10pt\def\C{\hbox{\open C}}\C\setminus{\cal S}_\tau$.

Our results have applications to the study of the eigenvalues of random normal matrices. The auxiliary results include weighted L2‐estimates for the equation
${\bar \partial} u=f$
when f is a suitable test function and the solution u is restricted by a polynomial growth bound at ∞. © 2009 Wiley Periodicals, Inc.
Two‐, One‐, and Zero‐Dimensional Elemental Nanostructures Based on Ge9‐Clusters
Authors: Karttunen Antti J. , Fässler Thomas F. , Linnolahti Mikko , Pakkanen Tapani A.
Published: May 2010

We investigated the structural principles of novel germanium modifications derived by oxidative coupling of Zintl‐type [Ge9]4−clusters in various ways. The structures, stabilities, and electronic properties of the predicted {2∞[Ge9]n} sheet, {1∞[Ge9]n} nanotubes, and fullerene‐like {Ge9}n cages were studied by using quantum chemical methods. The polyhedral {Ge9}n cages are energetically comparable with bulk‐like nanostructures of the same size, in good agreement with previous experimental findings. Three‐dimensional structures derived from the structures of lower dimensionality are expected to shed light on the structural characteristics of the existing mesoporous Ge materials that possess promising optoelectronic properties. Furthermore, 3D networks derived from the polyhedral {Ge9}n cages lead to structures that are closely related to the well‐known LTA zeolite framework, suggesting further possibilities for deriving novel mesoporous modifications of germanium. Raman and IR spectra and simulated X‐ray diffraction patterns of the predicted materials are given to facilitate comparisons with experimental results. The studied novel germanium modifications are semiconducting, and several structure types possess noticeably larger band gaps than bulk α‐Ge.
Silver Coated Platinum Core–Shell Nanostructures on Etched Si Nanowires: Atomic Layer Deposition (ALD) Processing and Application in SERS
Authors: Sivakov Vladimir A. , Höflich Katja , Becker Michael , Berger Andreas , Stelzner Thomas , Elers Kai‐Erik , Pore Viljami , Ritala Mikko , Christiansen Silke H.
Published: May 2010

A new method to prepare plasmonically active noble metal nanostructures on large surface area silicon nanowires (SiNWs) mediated by atomic layer deposition (ALD) technology has successfully been demonstrated for applications of surface‐enhanced Raman spectroscopy (SERS)‐based sensing. As host material for the plasmonically active nanostructures we use dense single‐crystalline SiNWs with diameters of less than 100 nm as obtained by a wet chemical etching method based on silver nitrate and hydrofluoric acid solutions. The SERS active metal nanoparticles/islands are made from silver (Ag) shells as deposited by autometallography on the core nanoislands made from platinum (Pt) that can easily be deposited by ALD in the form of nanoislands covering the SiNW surfaces in a controlled way. The density of the plasmonically inactive Pt islands as well as the thickness of noble metal Ag shell are two key factors determining the magnitude of the SERS signal enhancement and sensitivity of detection. The optimized Ag coated Pt islands on SiNWs exhibit great potential for ultrasensitive molecular sensing in terms of high SERS signal enhancement ability, good stability and reproducibility. The plasmonic activity of the core‐shell Pt//Ag system that will be experimentally realized in this paper as an example was demonstrated in numerical finite element simulations as well as experimentally in Raman measurements of SERS activity of a highly diluted model dye molecule. The morphology and structure of the core‐shell Pt//Ag nanoparticles on SiNW surfaces were investigated by scanning‐ and transmission electron microscopy. Optimized core–shell nanoparticle geometries for maximum Raman signal enhancement is discussed essentially based on the finite element modeling.
Measuring corporate environmental justice performance
Authors: Ash Michael , Boyce James K.
Published: May 2010

Measures of corporate environmental justice performance can be a valuable tool in efforts to promote corporate social responsibility and to document systematic patterns of environmental injustice. This paper develops such a measure based on the extent to which toxic air emissions from industrial facilities disproportionately impact racial and ethnic minorities and those on low incomes. Applying the measure to 100 major corporate air polluters in the United States, we find wide variation in the extent of disproportional exposures. In 54 cases, minorities, who represent 31.8% of the US population, bear excess burden; in 15 of these cases, the minority share exceeds half of the total human health impacts from the firm's industrial air pollution. In 66 cases, poor people, who represent 12.8% of the US population, bear excess burden. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Interaction of Short Laser Pulses in Wavelength Range from Infrared to X‐ray with Metals, Semiconductors, and Dielectrics
Authors: Inogamov N. A. , Faenov A. Ya. , Zhakhovskii V. V. , Skobelev I. Yu. , Khokhlov V. A. , Kato Y. , Tanaka M. , Pikuz T. A. , Kishimoto M. , Ishino M. , Nishikino M. , Fukuda Y. , Bulanov S. V. , Kawachi T. , Petrov Yu. V. , Anisimov S. I. , Fortov V. E.
Published: May 2010

Laser‐matter interaction is defined by an electronic band structure of condensed matter and frequency ωL of electromagnetic radiation. In the range of moderate fluences, the energy absorbed by electrons from radiation finally thermalizes in the ion thermal energy. The thermalization processes are different for optical as compared with X‐ray quanta and for metals relative to semiconductors and dielectrics, since the light absorption and electron‐electron, electron‐ion dynamics are sensitive to the electron population in a conduction band and the width of a forbidden gap. Although the thermalization processes are different, the final state is simply a heated matter. Laser heating creates powerful stresses in a target if duration of a laser pulse τL is short in acoustic time scale. Nucleation and material removal take place under such stresses. Such way of removal is called here the spallative ablation. Thus the spallative ablation is an ablation mechanism universally important for qualitatively different materials and quanta (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Time Evolution from Weak to Strong Coupling in a Spherically Confined Dusty Plasma
Authors: Kählert H. , Bonitz M.
Published: May 2010

Langevin dynamics simulations are performed to study the emergence of correlations in a spherically confined dusty plasma. We follow the time evolution of a laser‐heated initial plasma during its approach to the neutral gas temperature. The effect of the cooling rate is investigated in detail and the time scales for the emergence of the shell structure are compared. In strongly damped systems the correlation buildup is found to be slower than in weakly dissipative systems. The role of the confinement potential for the shell structure is explored by means of Monte Carlo simulations. In a linear and a quartic confinement the shells emerge at the cluster boundary, but density modulations are also found near the trap center in the former case (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Semi‐Classical Model of Strongly Correlated Coulomb Systems in Weak Magnetic Field
Authors: Ciftja O.
Published: May 2010

The integer and fractional quantum Hall effects are two remarkable macroscopic quantum phenomena occurring in two‐dimensional strongly correlated electronic systems at high magnetic fields and low temperatures. Quantization of Hall resistivity in the very high magnetic field regime at partial filling of the lowest Landau level indicates the stabilization of an electronic liquid quantum Hall phase of matter. Other interesting phases that differ from the quantum Hall phases take prominence in weaker magnetic fields when many more Landau levels are filled. These states manifest anisotropic magneto‐transport properties and, under certain conditions, appear to mimic charge density waves and/or liquid crystalline phases. One way to understand such a behavior has been in terms of effective interaction potentials confined to the highest Landau level partially filled with electrons. In this work we show that, for weak magnetic fields, such a quantum treatment of these strongly correlated Coulomb systems resembles a semi‐classical model of rotating electrons in which the time‐averaged interaction potential can be expressed solely in terms of guiding center coordinates. We discuss how the features of this semi‐classical effective potential may affect the stability of various strongly correlated electronic phases in the weak magnetic field regime (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Calculation of Canonical Properties and Excited States by Path Integral Numerical Methods
Authors: Vorontsov‐Velyaminov P. N. , Voznesenskiy M. A. , Polyakov E. A. , Lyubartsev A. P.
Published: May 2010

Path integral Monte Carlo method in the expanded ensemble is used for calculation of the ratio of partition functions for different classes of permutations treating the problem of several interacting identical particles (fermions) in an external field. Wang‐Landau algorithm is used for adjustment of balancing factors. For systems consisting of greater than two number of particles we propose an advanced variant of our approach which implies calculation of the ratio of positive and negative contributions to the partition function.

Densities and energies of the sequence of excited states starting from the ground state for a system of non interacting quantum particles are calculated in turn, one by one, by means of considering systems with artificially excluded lowest energy levels and further obtaining of the ”ground state” of each next system constructed in this way. The idea of evaluation of densities of excited states for a quantum system with interparticle interaction by evaluating density difference between systems of different number of noninteracting Fermi‐copies of the system of interest is realized in terms of cyclic expansion formalism for a simple 2D system of two spinless fermions interacting via Coulomb repulsion (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation an Effective Interaction Potential of Dust Particles in Nonideal Dusty Plasma
Authors: Ramazanov T. S. , Kodanova S. K. , Daniyarov T. T. , Moldabekov Zh. A.
Published: May 2010

Interaction between dusty particles remains to be an interesting issue that still requires deeper theoretical and experimental investigations. In the present paper we formulate a theoretical approach to the calculation of effective interaction potential of dust particles on the basis of Poisson equation and experimentally measured pair correlation functions. By application of our model to the data from the liquid phase of dust formations in stratified dc glow discharge, it is shown that there is an attractive component in the interaction of dust particle (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ordinary variations in human maternal caregiving in infancy and biobehavioral development in early childhood: A follow‐up study
Authors: Hane Amie Ashley , Henderson Heather A. , Reeb‐Sutherland Bethany C. , Fox Nathan A.
Published: May 2010

Rodent models of early caregiving find that pups reared by dams providing low levels of early stimulation subsequently display heightened stress reactivity and social aggression. We examined these effects in humans by investigating the effects of early caregiving on markers of biobehavioral development at ages 2 and 3 years. This study extended the findings reported by Hane and Fox (Hane and Fox [2006] Psychol. Sci. 17: 550–556) in which 185 mothers and infants were observed and scored for variations in maternal caregiving behavior (MCB) at age 9 months. Relative to young children who received high‐quality MCB in infancy, those who received low‐quality MCB showed significantly higher socially inhibited behavior with adults, right frontal electroencephalographam (EEG) asymmetry, aggressive play, and maternal reported internalizing behavior problems and anger proneness. These effects were independent of early temperamental reactivity. Results parallel rodent models and demonstrate that ordinary variations in MCB influence stress reactivity and social behavior in young children. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 558–567, 2010.
An improved Flp deleter mouse in C57Bl/6 based on Flpo recombinase
Authors: Kranz Andrea , Fu Jun , Duerschke Kristin , Weidlich Stefanie , Naumann Ronald , Stewart A. Francis , Anastassiadis Konstantinos
Published: May 2010

Recently, a codon improved version of the Flpe site specific recombinase, termed Flpo, was reported as having greatly improved performance in mammalian cell applications. However, the degree of improvement could not be estimated because essentially no Flpe activity was observed. Here, we compare Flpe and Flpo accurately in a mammalian cell assay to estimate that Flpo is about five times more active than Flpe and similar to Cre and Dre. Consequently, we generated a Flpo deleter mouse line from the JM8 C57Bl/6 ES cells used in the EUCOMM and KOMP systematic knock‐out programs. In breeding experiments, we show that the Flpo deleter delivers complete recombination using alleles that are incompletely recombined by a commonly used Flpe deleter. This indicates that the Flpo deleter is more efficient. genesis 48:512–520, 2010. © 2010 Wiley‐Liss, Inc.
Influence of the hydrologic regime on resource availability in a semi‐arid stream‐riparian corridor
Authors: Harms Tamara K. , Grimm Nancy B.
Published: May 2010

The hydrologic regime of an ecosystem directly affects ecological processes by controlling water availability, but may also have indirect effects by influencing resource availability. To clarify interactions between the hydrologic regime and resource availability, we quantified the timescales over which precipitation and discharge correlated with abundance of dissolved carbon, nitrogen, and phosphorus in the stream–riparian corridor of the San Pedro River, a large desert river. We hypothesized that the hydrologic regime drives regimes of resource availability during flushing events caused by variation in source areas of run‐off generation. We also hypothesized that seasonal droughts may result in accumulation of resources within the catchment. Such accumulations would contribute to high solute concentrations in receiving waters following dry periods. To test these hypotheses, we compiled seasonal datasets over 4–6 years and used regression analyses to determine the temporal extents at which solute concentrations and transformations were correlated with precipitation and stream discharge. Concentrations of most biologically reactive solutes were unrelated to precipitation or discharge, suggesting overlapping influences of myriad biological and transport processes probably operating on event or shorter timescales. Concentration of phosphate [soluble reactive phosphate (SRP)], NO3−: SRP, and NO3−: NH4+in the stream were positively correlated with precipitation abundance over weeks and up to 2 months, supporting the flushing hypothesis. Microbial processes in floodplain soils responded to precipitation and discharge, suggesting that biological processes may mediate relationships between hydrology and resource availability. In this large, semi‐arid catchment, resource availability is linked to hydrology via hydrologic transport, flowpath characteristics, and biotic processing. Copyright © 2010 John Wiley & Sons, Ltd.
HLA‐F is a surface marker on activated lymphocytes
Authors: Lee Ni , Ishitani Akiko , Geraghty Daniel E.
Published: May 2010

Of the three nonclassical class I antigens expressed in humans, HLA‐F has been least characterized with regard to expression or function. In this study, we examined HLA‐F expression focusing on lymphoid cells, where our previous work with homologous cell lines had demonstrated surface HLA‐F expression. HLA‐F protein expression was observed by Western blot analysis in all resting lymphocytes, including B cells, T cells, NK cells, and monocytes, all of which lacked surface expression in the resting state. Upon activation, using a variety of methods to activate different lymphocyte subpopulations, all cell types that expressed HLA‐F intracellularly showed an induction of surface HLA‐F protein. An examination of peripheral blood from individuals genetically deficient for TAP and tapasin expression demonstrated the same activation expression profiles for HLA‐F, but with altered kinetics post‐activation. Further analysis of CD4+CD25+ Treg showed that HLA‐F was not upregulated on the major fraction of these cells when they were activated, whereas CD4+CD25− T cells showed strong expression of surface HLA‐F when activated under identical conditions. These findings are discussed with regard to possible functions for HLA‐F and its potential clinical use as a marker of an activated immune response.
General Route to the Fabrication of ZnS and M‐Doped (M = Cd2+, Mn2+, Co2+, Ni2+, and Eu3+) ZnS Nanoclews and a Study of Their Properties
Authors: Dong Lihong , Liu Yang , Zhuo Yujiang , Chu Ying
Published: May 2010

In a mixed solvent composed of water and ethylenediamine, pure and ion‐doped (Cd2+, Mn2+, Co2+, Ni2+, Eu3+, etc.) clew‐like ZnS nanostructures, self‐assembled by curled ZnS nanowires, were synthesized by means of a hydrothermal route. These nanoclews possess a high specific surface area and can be separated easily from solution by natural settlement due to the self‐assembled structure; thus, they can be used in the field of photocatalysis. Photocatalytic experiments indicated that the pure ZnS nanoclews presented higher photocatalytic activity under UV irradiation, and the photocatalytic activity of the recycled ZnS nanoclews does not change noticeably after five reaction cycles. Furthermore, the CdxZn1–xS nanoclews showed high photocatalytic activity driven by visible light when the value of x was in the range from 0.3 to 0.7. The photoluminescence intensity of Eu3+‐doped ZnS nanoclews increased significantly compared with pure ZnS nanoclews. The formation mechanism of the ZnS nanoclews is also discussed.
Crystallization of Uranyl Salts from Dialkylimidazolium Ionic Liquids or Their Precursors
Authors: Cocalia Violina , Smiglak Marcin , Kelley Steven P. , Shamshina Julia L. , Gurau Gabriela , Rogers Robin D.
Published: May 2010

The interaction of uranyl nitrate hexahydrate with three ionic liquids and one ionic liquid precursor with minimal solvent addition led to the isolation and crystallographic characterization of four new uranyl salts: bis(1,3‐dimethylimidazolium) bis‐μ‐hydroxo‐bis[bis(nitrato‐O,O)dioxouranate(VI)], bis(1‐ethyl‐3‐methylimidazolium) bis‐μ‐hydroxo‐bis[bis(nitrato‐O,O)dioxouranate(VI)], bis(1,2,3‐trimethylimidazolium) bis‐μ‐hydroxo‐bis[bis(nitrato‐O,O)dioxouranate(VI)], and bis(1‐ethyl‐3‐methylimidazolium) trichlorobis(nitrato‐O,O)dioxouranate(VI). Each ion in the four isolated salts has precedence in the crystallographic literature, although the exact combinations of ions we observe in these salts are new. Some interesting differences in the packing of the ions can be related to the lack of an acidic C2‐H ring hydrogen atom in the 1,2,3‐trimethylimidazolium cation. It is suggested that future studies of these reactions be carried out under more strictly anhydrous conditions.
Pauson–Khand Reaction of Allenic Hydrocarbons: Synthesis of 4‐Alkylidenecyclopentenones
Authors: Antras Frédéric , Laurent Stéphane , Ahmar Mohammed , Chermette Henry , Cazes Bernard
Published: May 2010

The carbonyldicobalt‐mediated alkyne/allene/CO cocyclization gives 4‐alkylidenecyclopentenones as the major [2+2+1] cycloadducts. The regio‐ and stereoselectivities depend mainly on the substitution pattern of both the alkyne and the allenic moieties, which can be rationalized using the Magnus mechanism. However, contrary to this model, and in agreement with more recent mechanistic studies, our results provide evidence that both initial pseudo‐equatorial and pseudo‐axial coordination modes of the allenic hydrocarbons onto one of the cobalt atoms of the primary alkyne–dicobalt complex are involved. DFT calculations supporting both these coordination modes are given.
[C60(CN)5]–: A Remarkably Stable [60]Fullerene Anion
Authors: Troshin Pavel A. , Khakina Ekaterina A. , Peregudov Alexander S. , Konarev Dmitry V. , Soulimenkov Ilya V. , Peregudova Svetlana M. , Lyubovskaya Rimma N.
Published: May 2010

Reaction of C60Cl6 with organic cyanide yielded an ionic salt comprising the fullerene anion [C60(CN)5]–. This anion showed unprecedented stability in air and in solutions in the presence of water, organic and inorganic acids, and various electrophiles. The remarkable stability of the [C60(CN)5]– anion opens wide opportunities for the design of various air‐stable salts incorporating different cations (metallocene, tetrathiafulvalene, and etc.) that might reveal valuable magnetic or electronic properties and find wide application in the field of material science.
Metal‐Catalyzed Reactions between 2‐Azabicyclo[2.2.1]hept‐5‐en‐3‐ones and Arylboronic Acids
Authors: Abe Takumi , Takeda Hiroyuki , Takahashi Yumi , Miwa Yoshihisa , Yamada Koji , Ishikura Minoru
Published: May 2010

Cu‐ and Rh‐catalyzed coupling reactions of 2‐azabicyclo[2.2.1]hept‐5‐en‐3‐ones (1) with arylboronic acids were successful carried out under microwave irradiation conditions and yielded N‐aryl and C‐aryl derivatives of 1, respectively.
Unexpected Rearrangement Leading to Formation of a 1,3‐Bis(triphenylphosphonio)prop‐1‐en‐3‐idyl Carboxylate
Authors: Aitken R. Alan , Cleghorn Lee P. , Leitch Rebecca M. , Morrill Louis C. , Slawin Alexandra M. Z.
Published: May 2010

Whereas biphenyl‐4,4′‐dicarbonyl dichloride reacts with methylenetriphenylphosphorane to give the expected bis(acylylide) 1, the same reaction of biphenyl‐2,2′‐dicarbonyl dichloride results in a multistep rearrangement leading to the zwitterionic 2‐[1,3‐bis(triphenylphosphonio)prop‐1‐en‐3‐id‐2‐yl]biphenyl‐2′‐carboxylate 2. X‐ray crystal structures of both 1 and 2 are reported.
Total Synthesis of Calystegine B4
Authors: Moosophon Panawan , Baird Morwenna C. , Kanokmedhakul Somdej , Pyne Stephen G.
Published: May 2010

The total synthesis of calystegine B4 was achieved in 10 steps from (–)‐D‐lyxose by using a new synthetic strategy to obtain the requisite protected hydroxylated 4‐aminocyclohept‐2‐en‐1‐one without the problem of regioisomer formation that was a problem in the earlier synthesis of this natural product. The key steps included a Petasis–borono‐Mannich reaction and a ring‐closing metathesis reaction.
Biooxidation of Primary Alcohols to Aldehydes through Hydrogen Transfer Employing Janibacter terrae
Authors: Orbegozo Thomas , de Vries Johannes G. , Kroutil Wolfgang
Published: May 2010

Chemoselective oxidations still represent a challenge for chemists. Lyophilized cells of Janibacter terrae were employed for the chemoselective oxidation of primary alcohols to the corresponding aldehydes by hydrogen transfer with the use of acetaldehyde as the hydrogen acceptor. Secondary alcohol moieties were transformed at a much slower rate. The substrate spectrum encompasses substituted benzyl alcohols, whereby substrates with a substituent in the meta position were well tolerated, whereas only very small substituents were tolerated in the ortho position. Furthermore, n‐alkanols and allylic alcohols were transformed with good conversions. The biocatalyst was compatible with DMSO as a water miscible organic solvent up to 30 % v/v.
Bicyclic Sultams with a Nitrogen at the Bridgehead and a Sulfur Atom in the Apex Position: Facile Preparation and Conformational Properties
Authors: Rassadin Valentin A. , Grosheva Daria S. , Tomashevskiy Aleksandr A. , Sokolov Viktor V. , Yufit Dmitry S. , Kozhushkov Sergei I. , de Meijere Armin
Published: May 2010

A practical synthesis of bicyclic sultams with a pyramidal bridgehead nitrogen atom and a sulfur atom in the apex position has been elaborated. Compounds with 1‐azathiabicyclo[2.2.1]heptane (12a), ‐bicyclo[3.2.1]octane (12b, 12d), and ‐bicyclo[3.3.1]nonane (13b) skeletons were obtained by direct twofold inter/intramolecular alkylation of corresponding monocyclic sultams 9 and 10 with α,ω‐dihalides 11 in K2CO3/DMF in 56, 68, 52 and 52 % yield, respectively. On the other hand, a 1‐aza‐9‐thiabicyclo[4.2.1]nonane derivative (12c) could be prepared only by stepwise dialkylation in 24 % overall yield. Structural and conformational properties of four of the newly prepared bicyclic sultams in solution as well as in the solid state are discussed.
Directly Heated Bismuth Film Electrodes Based on Gold Microwires
Authors: Jacobsen Martin , Duwensee Heiko , Wachholz Falko , Adamovski Miriam , Flechsig Gerd‐Uwe
Published: May 2010

As a nontoxic substitute for mercury electrodes, bismuth electrodes attained a lot of attention during the last years. In this report we describe for the first time the preparation of two different directly heatable bismuth‐modified microwire electrodes. We characterized the electrochemical behaviour using cyclic voltammetry in acetate buffer and alkaline tartrate solution. The bismuth electrodes show a significantly wider potential window compared with bare gold wires. In the presence of picric acid as one example for the detection of explosives, the bismuth electrodes deliver higher signals. By applying heat during the measurements, the signals can be enhanced further. We used the temperature pulse amperometry (TPA) technique to improve the electrochemical response at the different types of electrodes. In this preliminary study, we were able to detect 3 ppm traces of picric acid.
Antimony Film Microelectrode for Anodic Stripping Measurement of Cadmium(II), Lead(II) and Copper(II)
Authors: Slavec Marija , Hocevar Samo B. , Baldrianova Lucie , Tesarova Eva , Svancara Ivan , Ogorevc Bozidar , Vytras Karel
Published: May 2010

The antimony film microelectrode (SbFME) is presented for measuring trace heavy metal ions in combination with anodic stripping voltammetry. The SbFME was tested in model solutions of 0.01 M HCl containing Cd(II) and Pb(II) in the presence of dissolved oxygen. The microsensor exhibited good linear behavior in the examined concentration range 20 μg L−1 to 100 μg L−1 and LoD of 1.9 and 3.1 μg L−1 for Cd(II) and Pb(II), respectively. The suitability of SbFME for measuring trace levels of Cu(II) was demonstrated using the standard reference material of natural water exploiting the sensor's specific characteristic of low re‐oxidation signal for antimony.
Voltammetric Determination of Glucose at Bismuth‐Modified Mesoporous Platinum Microelectrodes
Authors: Daniele Salvatore , Battistel Dario , Bergamin Simone , Bragato Carlo
Published: May 2010

Mesoporous platinum microeletrodes (MPtEs) modified by a mono‐ or submonolayer of adsorbed bismuth (Bi‐MPtE) were investigated and employed for the detection of glucose in 0.2 M NaOH solutions. The mesoporous platinum films were electrodeposited from hexachloroplatinic acid dissolved in the aqueous domain of the lyotropic liquid crystalline phase of octaethylene glycol monohexadecyl ether. Bismuth ad‐atoms were obtained by under potential deposition of Bi3+ ions in 0.5 M H2SO4 solutions. The coverage of the MPtEs by irreversibly adsorbed bismuth was checked in either a 0.5 M H2SO4 or 0.2 M NaOH solution free of Bi3+ ions, and exploiting the charge involved in the hydrogen adsorption/desorption peaks, which decreased in proportion to the amount of platinum sites covered by bismuth. The catalytic activity of a series of Bi‐MPtEs towards the oxidation of glucose was investigated by cyclic voltammetry, and the overall behaviour was found to be superior of that of the corresponding MPtEs. Also, at Bi‐MPtEs, the effect of interference by ascorbic acid was minimal. Calibration plots were examined over the glucose concentration range from 0.5 mM to 300 mM. It was found that linearity, between current against glucose concentration, and sensitivity depended on the electrode type and real surface area. At the Bi‐MPtEs both linear range and sensitivity were larger than those of the MPtEs. These results were discussed in terms of high tolerance of the Bi‐MPtEs towards the intermediate poisons originated in the electrooxidation process of glucose.
Cationic and anionic lipid‐based nanoparticles in CEC for protein separation
Authors: Nilsson Christian , Harwigsson Ian , Birnbaum Staffan , Nilsson Staffan
Published: May 2010

The development of new separation techniques is an important task in protein science. Herein, we describe how anionic and cationic lipid‐based liquid crystalline nanoparticles can be used for protein separation. The potential of the suggested separation methods is demonstrated on green fluorescent protein (GFP) samples for future use on more complex samples. Three different CEC‐LIF approaches for protein separation are described. (i) GFP and GFP N212Y, which are equally charged, were separated with high resolution by using anionic nanoparticles suspended in the electrolyte and adsorbed to the capillary wall. (ii) High efficiency (800 000 plates/m) and peak capacity were demonstrated separating GFP samples from Escherichia coli with cationic nanoparticles suspended in the electrolyte and adsorbed to the capillary wall. (iii) Three single amino‐acid‐substituted GFP variants were separated with high resolution using an approach based on a physical attached double‐layer coating of cationic and anionic nanoparticles combined with anionic lipid nanoparticles suspended in the electrolyte. The soft and porous lipid‐based nanoparticles were synthesized by a one‐step procedure based on the self‐assembly of lipids, and were biocompatible with a large surface‐to‐volume ratio. The methodology is still under development and the optimization of the nanoparticle chemistry and separation conditions can further improve the separation system. In contrast to conventional LC, a new interaction phase is introduced for every analysis, which minimizes carry‐over and time‐consuming column regeneration.
Regulation of L‐type Ca++ currents and process morphology in white matter oligodendrocyte precursor cells by golli‐myelin proteins
Authors: Fulton Daniel , Paez Pablo M. , Fisher Robin , Handley Vance , Colwell Christopher S. , Campagnoni Anthony T.
Published: May 2010

The golli myelin basic proteins are expressed in oligodendroglial precursor cells (OPCs) where they play a role in regulating Ca2+ homeostasis. During depolarization, they influence process outgrowth and migration through their action on voltage‐operated Ca2+ channels (VOCCs). To identify ion channels that are modulated by golli, we examined the electrophysiological properties of VOCCs in OPCs in the white matter of golli knock‐out and control mice. OPCs exhibited two distinct Ca2+ channels, which were distinguished by their voltage dependence and pharmacological profiles and which exhibited many of the hallmarks of LVA/T‐type and HVA/L‐type Ca2+ channels. The density of high‐voltage‐activated (HVA) currents was reduced in OPCs recorded in golli‐KO tissue, while low‐voltage‐activated (LVA) currents remained unaltered in these cells. These data indicate that golli exerts an exclusive influence on L‐type Ca2+ channels in OPCs. Oligodendrocytes (OLs) also displayed LVA and HVA currents, although the density of these currents was much reduced at this developmental stage. These currents were not altered in golli‐KO OLs showing the influence of golli on L‐type Ca2+ channels is restricted to a specific time‐window during the course of oligodendroglial development. The actions of golli on OPC L‐type Ca2+ channels were accompanied by changes in process morphology, including a reduction in process complexity and the appearance of enlarged varicosities that decorated these cellular processes. These data on L‐type Ca2+ channels and process development provide in situ evidence for the influence of golli on VOCCs, and offer an explanation for the hypomyelination observed in the brains of golli‐KO mice. © 2010 Wiley‐Liss, Inc.
Effects of axon degeneration on oligodendrocyte lineage cells: Dorsal rhizotomy evokes a repair response while axon degeneration rostral to spinal contusion induces both repair and apoptosis
Authors: Sun Fang , Lin Chien‐Liang Glenn , Mctigue Dana , Shan Xiu , Tovar C. Amy , Bresnahan Jacqueline C. , Beattie Michael S.
Published: May 2010

Wallerian degeneration in the dorsal columns (DC) after spinal cord injury (SCI) is associated with microglial activation and prolonged oligodendrocyte (OL) apoptosis that may contribute to demyelination and dysfunction after SCI. But, there is an increase in OL lineage cells after SCI that may represent a reparative response, and there is evidence for remyelination after SCI. To assess the role of axonal degeneration per se in OL apoptosis and proliferation, we cut the L2‐S2 dorsal roots producing massive axonal degeneration and microglial activation in the DC, and found no evidence of OL loss or apoptosis. Rather, the numbers of OL‐lineage cells positive for NG2 and APC (CC1) increased, and BrdU studies suggested new OL formation. We then tested contusion SCI (cSCI) that results in comparable degeneration in the DC rostral to the injury, microglial activation, and apoptosis of DC OLs by eight days. NG2+ cell proliferation and oligodendrogenesis was seen as after rhizotomy. The net result of this combination of proliferation and apoptosis was a reduction in DC OLs, confirming earlier studies. Using an antibody to oxidized nucleic acids, we found rapid and prolonged RNA oxidation in OLs rostral to cSCI, but no evidence of oxidative stress in DC OLs after rhizotomy. These results suggest that signals associated with axonal degeneration are sufficient to induce OL proliferation, and that secondary injury processes associated with the central SCI, including oxidative stress, rather than axonal degeneration per se, are responsible for OL apoptosis. © 2010 Wiley‐Liss, Inc.
ApoD, a glia‐derived apolipoprotein, is required for peripheral nerve functional integrity and a timely response to injury
Authors: Ganfornina Maria D. , Do Carmo Sonia , Martínez Eva , Tolivia Jorge , Navarro Ana , Rassart Eric , Sanchez Diego
Published: May 2010

Glial cells are a key element to the process of axonal regeneration, either promoting or inhibiting axonal growth. The study of glial derived factors induced by injury is important to understand the processes that allow or preclude regeneration, and can explain why the PNS has a remarkable ability to regenerate, while the CNS does not. In this work we focus on Apolipoprotein D (ApoD), a Lipocalin expressed by glial cells in the PNS and CNS. ApoD expression is strongly induced upon PNS injury, but its role has not been elucidated. Here we show that ApoD is required for: (1) the maintenance of peripheral nerve function and tissue homeostasis with age, and (2) an adequate and timely response to injury. We study crushed sciatic nerves at two ages using ApoD knock‐out and transgenic mice over‐expressing human ApoD. The lack of ApoD decreases motor nerve conduction velocity and the thickness of myelin sheath in intact nerves. Following injury, we analyze the functional recovery, the cellular processes, and the protein and mRNA expression profiles of a group of injury‐induced genes. ApoD helps to recover locomotor function after injury, promoting myelin clearance, and regulating the extent of angiogenesis and the number of macrophages recruited to the injury site. Axon regeneration and remyelination are delayed without ApoD and stimulated by excess ApoD. The mRNA and protein expression profiles reveal that ApoD is functionally connected in an age‐dependent manner to specific molecular programs triggered by injury. © 2010 Wiley‐Liss, Inc.
Methodological approaches in developmental neuroimaging studies
Authors: Luna Beatriz , Velanova Katerina , Geier Charles F.
Published: May 2010

Pediatric neuroimaging is increasingly providing insights into the neural basis of cognitive development. Indeed, we have now arrived at a stage where we can begin to identify optimal methodological and statistical approaches to the acquisition and analysis of developmental imaging data. In this article, we describe a number of these approaches and how their selection impacts the ability to examine and interpret developmental effects. We describe preferred approaches to task selection, definition of age groups, selection of fMRI designs, definition of regions of interest (ROI), optimal baseline measures, and treatment of timecourse data. Consideration of these aspects of developmental neuroimaging reveals that unlike single‐group neuroimaging studies, developmental studies pose unique challenges that impact study planning, task design, data analysis, and the interpretation of findings. Hum Brain Mapp , 2010. © 2010 Wiley‐Liss, Inc.
Chinese children's moral evaluation of lies and truths—roles of context and parental individualism–collectivism tendencies
Authors: Fu Genyue , Brunet Megan K. , Lv Yin , Ding Xiaopan , Heyman Gail D. , Cameron Catherine Ann , Lee Kang
Published: May 2010

The present study examined Chinese children's moral evaluations of truths and lies about one's own pro‐social acts. Children ages 7, 9, and 11 were read vignettes in which a protagonist performs a good deed and is asked about it by a teacher, either in front of the class or in private. In response, the protagonist either tells a modest lie, which is highly valued by the Chinese culture, or tells an immodest truth, which violates the Chinese cultural norms about modesty. Children were asked to identify whether the protagonist's statement was the truth or a lie, and to evaluate how ‘good’ or ‘bad’ the statement was. Chinese children rated modest lies more positively than immodest truths, with this effect becoming more pronounced with age. Rural Chinese children and those with at least one nonprofessional parent rated immodest truths less positively when they were told in public rather than in private. Furthermore, Chinese children of parents with high collectivism scores valued modest lies more than did children of parents with low collectivism scores. These findings suggest that both macro‐ and micro‐cultural factors contribute significantly to children's moral understanding of truth and lie telling. Copyright © 2010 John Wiley & Sons, Ltd.