bluuebunny/crossref_metadata_2025 huggingface dataset:
Melatonin treatment potentiates neurodegeneration in a rat rotenone Parkinson's disease model
Authors: Tapias Victor , Cannon Jason R. , Greenamyre J. Timothy
Published: August 2009

Parkinson's disease (PD) is characterized pathologically by progressive neurodegeneration of the nigrostriatal dopamine (DA) system. Currently, the cause of the disease is unknown, except for a small percentage of familial cases (<10% of total). The rat rotenone model reproduces many of the pathological features of the human disease, including apomorphine‐responsive behavioral deficits, DA depletion, loss of striatal DA terminals and nigral dopaminergic neurons, and α‐synuclein/polyubiquitin‐positive cytoplasmic inclusions reminiscent of Lewy bodies. Therefore, this model is well‐suited to examine potential neuroprotective agents. Melatonin is produced mainly by the pineal gland and is known primarily for regulating circadian rhythms. It also has potent free radical scavenging and antiinflammatory properties. Melatonin has been reported to be neuroprotective in the 6‐hydroxydopamine (6‐OHDA) and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) models of PD. However, there are conflicting reports suggesting that melatonin does not provide neuroprotection in these models. Melatonin elicits significant functional changes in the nigrostriatal DA system that may affect 6‐OHDA and MPTP entry into cells. Therefore, rotenone is an ideal model for assessing protection, because it does not rely on the dopamine transporter uptake to exert neurotoxicity. In this study, the neuroprotective potential of melatonin in the rotenone PD model was assessed. Melatonin potentiated striatal catecholamine depletion, striatal terminal loss, and nigral DA cell loss. Indeed, melatonin alone elicited alterations in striatal catecholamine content. Our findings indicate that melatonin is not neuroprotective in the rotenone model of PD and may exacerbate neurodegeneration. © 2009 Wiley‐Liss, Inc.
A tephrostratigraphic record for the last glacial–interglacial cycle from Lake Ohrid, Albania and Macedonia
Authors: Vogel Hendrik , Zanchetta Giovanni , Sulpizio Roberto , Wagner Bernd , Nowaczyk Norbert
Published: August 2009

Here we present a tephrostratigraphic record (core Co1202) recovered from the northeastern part of Lake Ohrid (Republics of Macedonia and Albania) reaching back to Marine Isotope Stage (MIS) 6. Overall ten horizons (OT0702‐1 to OT0702‐10) containing volcanic tephra have been recognised throughout the 14.94 m long sediment succession. Four tephra layers were visible at macroscopic inspection (OT0702‐4, OT0702‐6, OT0702‐8 and OT0702‐9), while the remaining six are cryptotephras (OT0702‐1, OT0702‐2, OT0702‐3, OT0702‐5, OT0702‐7 and OT0702‐10) identified from peaks in K, Zr and Sr intensities, magnetic susceptibility measurements, and washing and sieving of the sediments. Glass shards of tephra layers and cryptotephras were analysed with respect to their major element composition, and correlated to explosive eruptions of Italian volcanoes. The stratigraphy and the major element composition of tephra layers and cryptotephras allowed the correlation of OT0702‐1 to AD 472 or AD 512 eruptions of Somma‐Vesuvius, OT0702‐2 to the FL eruption of Mount Etna, OT0702‐3 to the Mercato from Somma‐Vesuvius, OT0702‐4 to SMP1‐e/Y‐3 eruption from the Campi Flegrei caldera, OT0702‐5 to the Codola eruption (Somma‐Vesuvius or Campi Flegrei), OT0702‐6 to the Campanian Ignimbrite/Y‐5 from the Campi Flegrei caldera, OT0702‐7 to the Green Tuff/Y‐6 eruption from Pantelleria Island, OT0702‐8 to the X‐5 eruption probably originating from the Campi Flegrei caldera, OT0702‐9 to the X‐6 eruption of generic Campanian origin, and OT0702‐10 to the P‐11 eruption from Pantelleria Island. The fairly well‐known ages of these tephra layers and parent eruptions provide new data on the dispersal and deposition of these tephras and, furthermore, allow the establishment of a chronological framework for core Co1202 for a first interpretation of major sedimentological changes. Copyright © 2009 John Wiley & Sons, Ltd.
Ion‐Selective Optodes Measure Extracellular Potassium Flux in Excitable Cells
Authors: Harjes Daniel I. , Dubach J. Matthew , Rosenzweig Anthony , Das Saumya , Clark Heather A.
Published: August 2009

Optodes have been used for detection of ionic concentrations and fluxes for several years. However, their uses in biomedical applications have not yet been fully explored. This study investigates optodes as a potential sensor platform for monitoring cellular ion flux with attendant implications in the field of drug screening and toxicology. A prototype system was developed to quantitatively measure extracellular potassium flux from a monolayer of cardiomyocytes. Optodes were created and immobilized on a glass coverslip for fluorescent imaging. The system detected potassium (K+) ion flux during the repolarization phase of the cardiac action potential and further detected a decrease in the magnitude of the flux in the presence of a known K+ channel inhibitor by optically monitoring local K+ ion concentrations during field stimulation of the cardiomyocyte monolayer.

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Influence of PEG‐ran‐PPG Surfactant on Vapour Phase Polymerised PEDOT Thin Films
Authors: Fabretto Manrico , Müller Michael , Zuber Kamil , Murphy Peter
Published: August 2009

The oxidant, Fe(III) tosylate, was used in the vapour phase polymerisation (VPP) of PEDOT. The amphiphilic co‐polymer poly(ethylene glycol‐ran‐propylene glycol) was added and its influence examined. Both the PEDOT conductivity and optical contrast range increased with the inclusion of the co‐polymer, with the maximum being recorded at 4 wt.‐%. Loadings higher than this resulted in a systematic decrease in both conductivity and optical contrast. Evidence indicates that in addition to the beneficial anti‐crystallisation effect to the oxidant layer, the co‐polymer also reduces the effective reactivity of the oxidant, as demonstrated by slower polymerisation rates. Confirmation of the change in polymerisation rate was obtained using a quartz crystal microbalance (QCM). The slower polymerisation rate results in higher conductivity and optical contrast; however, XPS data confirmed that the co‐polymer remained within the PEDOT film post‐washing and this result explains why the performance decreases at high surfactant loadings.

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Discoidin domain receptor 2 (DDR2) is required for maintenance of spermatogenesis in male mice
Authors: Kano Kiyoshi , Kitamura Ayami , Matsuwaki Takashi , Morimatsu Masami , Naito Kunihiko
Published: August 2009

Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase (RTK). We recently identified homozygous smallie mutant mice (BKS.HRS. Ddr2slie/slie/J, Ddr2slie/slie mutants), which lack a functional DDR2. Ddr2slie/slie mutant mice are dwarfed and infertile due to peripheral dysregulation of the endocrine system. To understand the role of DDR2 signaling in spermatogenesis, we studied the expression of several receptors, enzymes, and proteins related to spermatogenesis in wild‐type and Ddr2slie/slie mutant mice at 10 weeks and 5 months of age. DDR2 were expressed in adult wild‐type male mice in Leydig cells. The number of differentiated spermatozoa in the seminal fluid was significantly lower in the Ddr2slie/slie mutant mice than in the wild‐type mice. The number of TUNEL‐positive cells was significantly greater in 5‐month‐old Ddr2slie/slie mutants. Testosterone was significantly reduced at 5 months of age, but LH was similar in both types of mice at both 10 weeks and 5 months of age. The expression levels of LH receptors (Lhcgr), StAR, P450scc, and Hsd3β6 were not significantly different between the two types of mice at 10 weeks of age, but they were significantly reduced in 5‐month‐old Ddr2slie/slie mutants compared to wild‐type mice of the same age. DDR2 was expressed in the Leydig cells of adult wild‐type male mice. In conclusion, our results indicated that DDR2 signaling plays a critical role in the maintenance of male spermatogenesis. Mol. Reprod. Dev. 77: 29–37, 2010. © 2009 Wiley‐Liss, Inc.
The role of children's routines of daily living, supervision, and maternal fatigue in preschool children's injury risk
Authors: Koulouglioti Christina , Cole Robert , Kitzman Harriet
Published: August 2009

The purpose of this study was to (a) explore the relationship between the lack of everyday routines and children's unintentional injuries, (b) examine two mechanisms of effect through which lack of routines might operate, children's sleep and maternal supervision, and (c) explore the influence of maternal fatigue in routines and maternal supervision. The sample comprised 264 mothers and their 3‐year‐old children. Routines were not directly related to children's injuries, but they moderated the relationship between maternal supervision and injuries. Lack of supervision was positively related to injuries only for children with infrequent everyday routines. Infrequent everyday routines were also related to inadequate children's sleep and maternal fatigue was inversely related to routines and maternal supervision. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32:517–529, 2009
A novel peak detection approach with chemical noise removal using short‐time FFT for prOTOF MS data
Authors: Zhang Shuqin , DeGraba Thomas J. , Wang Honghui , Hoehn Gerard T. , Gonzales Denise A. , Suffredini Anthony F. , Ching Wai‐Ki , Ng Michael K. , Zhou Xiaobo , Wong Stephen T. C.
Published: August 2009

Peak detection is a pivotal first step in biomarker discovery from MS data and can significantly influence the results of downstream data analysis steps. We developed a novel automatic peak detection method for prOTOF MS data, which does not require a priori knowledge of protein masses. Random noise is removed by an undecimated wavelet transform and chemical noise is attenuated by an adaptive short‐time discrete Fourier transform. Isotopic peaks corresponding to a single protein are combined by extracting an envelope over them. Depending on the S/N, the desired peaks in each individual spectrum are detected and those with the highest intensity among their peak clusters are recorded. The common peaks among all the spectra are identified by choosing an appropriate cut‐off threshold in the complete linkage hierarchical clustering. To remove the 1 Da shifting of the peaks, the peak corresponding to the same protein is determined as the detected peak with the largest number among its neighborhood. We validated this method using a data set of serial peptide and protein calibration standards. Compared with MoverZ program, our new method detects more peaks and significantly enhances S/N of the peak after the chemical noise removal. We then successfully applied this method to a data set from prOTOF MS spectra of albumin and albumin‐bound proteins from serum samples of 59 patients with carotid artery disease compared to vascular disease‐free patients to detect peaks with S/N≥2. Our method is easily implemented and is highly effective to define peaks that will be used for disease classification or to highlight potential biomarkers.
Influence of the secondary functionality on the radical‐vinyl chemistry of highly reactive monoacrylates
Authors: Kilambi Harini , Reddy Sirish K. , Schneidewind Lauren , Stansbury Jeffrey W. , Bowman Christopher N.
Published: August 2009

The impact of secondary functionalities on the radical‐vinyl chemistry of monoacrylates characterized by secondary functionalities that dramatically enhance their polymerization rate was elucidated utilizing experimental and computational techniques. Firstly, bulk interactions affecting the acrylate reactivity towards photopolymerization were removed by polymerizing at 5 wt % monomer in 1,4‐dioxane. Following deconvolution of bulk interactions impacting reactivity towards photopolymerization, a linear correlation between average polymerization rates and Michael addition reaction rate constants was observed on a logarithmic scale. This result indicates that the presence of the secondary functionality intramolecularly alters the monomer chemistry in a manner which impacts both of these distinct reaction types in a similar manner. These monomers exhibited reduced activation energies in both Michael addition and photopolymerization reactions as compared to hexyl acrylate. Reduction up to 20 ± 8 kJ mole−1was observed for Michael addition reactions and 12 ± 1 kJ mole−1 for photopolymerization reactions, thereby explaining the higher reactivity of the acrylates characterized by the secondary functionalities. Cyclic voltammetry experiments conducted to investigate the nature of the acrylic double bonds indicated that the rapidly polymerizing acrylates are more readily reduced as compared to traditional acrylates. Further, a distinct monotonic correlation of the irreversible cathodic peak potentials of the (meth)acrylates to photopolymerization and Michael addition reactivity was observed. The computationally estimated acrylic LUMO energies characterized by the secondary functionalities (−2.3 eV to −2.7 eV) were also found to be lower relative to hexyl acrylate (−2.2 eV). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4859–4870, 2009
Synthesis of highly refractive polyimides derived from 3,6‐bis(4‐aminophenylenesulfanyl)pyridazine and 4,6‐bis(4‐aminophenylenesulfanyl)pyrimidine
Authors: You Nam‐Ho , Nakamura Yasuhiro , Suzuki Yasuo , Higashihara Tomoya , Ando Shinji , Ueda Mitsuru
Published: August 2009

A series of aromatic polyimides (PIs) containing pyridazine or pyrimidine in their main chains has been developed. All of the PIs were prepared from newly synthesized diamines, 3,6‐bis(4‐aminophenylenesulfanyl)pyridazine (APP), 4,6‐bis(4‐aminophenylenesulfanyl)pyrimidine (APPM) and aromatic dianhydrides, 4,4′‐[p‐thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA) and 4,4′‐oxydiphthalic anhydride (ODPA) via the conventional two‐step polycondensation. The PIs showed good thermal stability with 10% weight loss at temperatures above 450 °C and glass transition temperatures above 190 °C. Films with a 10‐μm thickness exhibited good optical transparency above 80% at 500 nm, high refractive indices ranging from 1.7218 to 1.7499, and low birefringence between 0.0066 and 0.0102. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4886–4984, 2009
Preparation of poly(amino‐amide) particles complexed with ZnO particles using silane coupling agents
Authors: Yoshioka Yayoi
Published: August 2009

Poly(amino‐amide) particles were prepared by reacting 4,4′‐diphenyldicarbonyl chloride and 3,3′‐diaminobenzidine using a precipitation polymerization method with ultrasonic irradiation. The resulting particles had a narrow size distribution with an average diameter of 334 nm and showed excellent dispersion stability in water. The particles obtained were then modified with silane coupling agents (GPES) by reacting the amino groups of the poly(amino‐amide) particles with the epoxide rings of the GPES molecules in N,N‐dimethylformamide or N‐methylpyrrolidone using di‐n‐butyltin dilaurate as a catalyst. The amount of GPES covalently bonded to the poly(amino‐amide) particles was found to depend strongly on the reaction solvent and catalyst used. The resulting particles showed a narrow size distribution and the connections among the particles were not observed. On the other hand, the particles before and after modification showed different thermal properties and dispersion stability in water. The GPES‐modified aromatic polyamide particles were then complexed with ZnO particles with an average diameter of about 20 nm in aqueous acetic acid solution. It was found that the surface of the aromatic polyamide particles was covered with ZnO particles via hydrolysis reaction. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4908–4918, 2009
Novel silver‐loaded semi‐interpenetrating polymer network gel films with antibacterial activity
Authors: Thatiparti Thimma Reddy , Kano Arihiro , Maruyama Atsushi , Takahara Atsushi
Published: August 2009

Novel semi‐interpenetrating polymer networks (SIPNs) based on segmented polyurethane‐urea and poly(N‐isopropylacrylamide‐co‐acrylic acid‐co‐butylmethacrylate) (poly(NIPAM‐co‐AA‐BMA)) were synthesized for the fabrication of silver nanoparticles (AgNPs) in the SIPN system that could be useful for wound dressing applications. The obtained SIPN films, after neutralization, showed high swelling in aqueous environments and good mechanical properties in both dry and hydrated states. Analysis of the dried SIPN films by differential scanning calorimetry and dynamic viscoelastic measurements revealed the presence of crosslinked copolymers as well as homopolymers in the SIPN system. The neutralized swollen SIPN film coordinated with the silver ions (Ag+) that were incorporated into it. AgNPs were subsequently formed by the reduction of Ag+. The formation of AgNPs was characterized by UV‐visible spectroscopy, atomic force microscopy, wide‐angle X‐ray diffraction, and thermogravimetric analysis (TGA). Bactericidal activity tests revealed a distinct zone of microbial inhibition within and around the silver‐doped SIPN films. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4950–4962, 2009
Formation of Nitrogen Functional Groups on Plasma Treated DLC
Authors: López‐Santos Carmen , Yubero Francisco , Cotrino José , Contreras Leopoldo , Barranco Angel , González‐Elipe Agustín R.
Published: August 2009

Diamond like carbon (DLC) thin films have been exposed to different nitrogen containing plasmas. A dielectric barrier discharge (DBD) at atmospheric pressure and a microwave discharge (MW) at low pressure using N2 and mixtures Ar + NH3 have been compared. Optical Emission and X‐ray Photoelectron spectroscopies, Atomic Force Microscopy and contact angle measurements have been used for this study. A DBD with Ar + NH3 is the most efficient method for DLC functionalization. Films treated with this plasma presented the highest concentration of amine groups as determined by derivatization with 4‐chlorobenzaldehyde. All the treated samples underwent a significant aging with time. The efficiency of the different plasmas for DLC functionalization is discussed in the light of the intermediate species detected in the plasma.

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Deposition and Characterization of Hard Coatings in the Material System V–Al–N by Reactive Magnetron Sputter Deposition
Authors: Kolozsvári Szilárd , Pesch Peter , Ziebert Carlos , Stueber Michael , Ulrich Sven
Published: August 2009

Binary and ternary hard coatings in the system V–Al–N were deposited with varying substrate bias at substrate temperatures around 350 °C by reactive d.c. and r.f. magnetron sputtering in an Ar/N2 gas mixture from a V and/or Al target. For each experiment, Si (100) and polished 1.2379 steel substrates were placed on the rotating substrate table. VN coatings were deposited at a constant Ar flow of 250 sccm, while the bias voltage was varied between −80 and −200 V. The influence of this variation on the mechanical properties hardness and reduced elastic modulus was examined by microindentation and the critical load of failure by scratch test, friction coefficient was determined by ball‐on‐disc tribometer tests. For the deposition of AlN and VAlN coatings bias voltage, Ar/N ratio and the total pressure were varied. The chemical composition of the obtained coatings was determined by electron microprobe analysis and the crystal structure of the films was characterized by X‐ray diffraction.
Effect of Substrate Temperature and RF Biasing on the Optical Properties of Titania‐Like Thin Films Obtained by Plasma Enhanced Chemical Vapor Deposition
Authors: Sonnenfeld Axel , Rudolf von Rohr Philipp
Published: August 2009

A low pressure radio frequency (RF) discharge (200 W) was operated in argon/oxygen with small admixtures of titanium(IV)isopropoxide (TTIP). By regulating the cooling temperature of the RF driven electrode, the influence of the substrate temperature and of the ion bombardment caused by the negative DC self‐bias of the RF electrode was investigated comparatively. Thin titania‐like films were obtained and characterized with respect to their cut‐off wavelength and their spectral absorption coefficient in the UV range. Accordingly, the cut‐off wavelength was found to be higher for films obtained on the DC‐self‐biased electrode. Here, its value appears independent of the substrate temperature and attained successively its maximum at 340 nm with deposition time. Furthermore, the absorption coefficients of films deposited on the DC self‐biased electrode are well superior to those obtained on the grounded substrate holder.
Polymer Surface Modification by Aerosol Based DBD Treatment of Foils
Authors: Mix Renate , Friedrich Joerg , Rau Alexander
Published: August 2009

The effect of different nebulized liquids directly introduced into the dielectric barrier discharge (DBD) was compared with simple air DBD treatment of polyethylene foils. Water, alcohols and aqueous solutions of different organic substances (environmentally compatible) and water soluble polymers were applied as aerosols and injected into the DBD zone. The DBD residence time (number of treatment cycles) and the power were varied. The durability of the surface modification effect was studied after removing of Low‐Molecular Weight Oxidized Material (LMWOM) by washing the samples with water and ethanol. The modified foils were characterized by XPS and contact angle measurements as a function of the applied plasma conditions. The concentration of functional groups at modified surfaces was estimated by derivatization and subsequent XPS measurement.

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PSA surge/flare‐up in patients with castration‐refractory prostate cancer during the initial phase of chemotherapy
Authors: Nelius T. , Filleur S.
Published: August 2009

BACKGROUND

Docetaxel‐based chemotherapy has shown great promise for the treatment of CRPC and is considered the current standard of care. PSA is mainly used as marker to monitor the treatment response. Several articles were published reporting an initial PSA surge/flare‐up after starting chemotherapy. The cause and the impact of this phenomenon are discussed controversially. The intention of this review is to define the significance of initial PSA surge/flare‐up and to increase awareness to this phenomenon in the urological community.

MATERIALS AND METHODS

A comprehensive literature search was performed in different data bases using various key words. Relevant articles and references between 1999 and 2009 were reviewed and analyzed for data on the association between chemotherapy and initial PSA surge/flare.

RESULTS

The incidence of a PSA surge/flare‐up ranges according to the reported studies between 7.6% and 13.6%. A PSA surge/flare‐up was reported up to 404% from baseline PSA level followed by PSA response. The median duration of a PSA surge/flare‐up is 2–3 weeks and can last up to 6–8 weeks. However, the occurrence of a PSA surge/flare‐up did not impact outcome and survival negatively compared to patients with an immediate PSA response.

CONCLUSIONS

A considerable portion of CRPC patients experience an initial PSA surge/flare‐up under systemic chemotherapy. The definitions used for PSA surge/flare‐up differ slightly in the literature. This issue needs to be solved since it might impact defining treatment response. As a PSA surge/flare‐up did not impact outcome and survival negatively, chemotherapy should be continued according to the literature addressing specifically the phenomenon of a PSA surge/flare‐up for a minimum of 8 weeks or 3 rounds of a 3‐weekly cycle chemotherapy regimen before further decisions are made about efficacy. However, Scher et al. recommended a 12‐week period drug exposure based on their results on PSA progression‐free survival and overall survival. This dilemma needs to be addressed in further data analysis in order to establish a general rule regarding when to stop chemotherapy. Physicians should be aware of this effect to avoid inadequate early discontinuation of chemotherapy. The underlying mechanisms of a PSA surge/flare‐up are still elusive and need further clarification. Prostate 69: 1802–1807, 2009. © 2009 Wiley‐Liss, Inc.
Adiponectin increases motility of human prostate cancer cells via adipoR, p38, AMPK, and NF‐κB pathways
Authors: Tang Chih‐Hsin , Lu Mu‐En
Published: August 2009

BACKGROUND

Prostate cancer is the most commonly diagnosed malignancy in men. Prostate cancer shows a predilection for metastasis to the bone. Adiponectin is a protein hormone secreted predominantly by differentiated adipocytes and involved in energy homeostasis. The aim of this study was to investigate whether adiponectin is associated with migration of prostate cancer cells.

METHOD

Cancer cells migration activity was examined using the Transwell assay. The p38 and AMPK phosphorylation was examined by using Western blot method. The cell surface expression of integrins was examined by using flow cytometry. The qPCR was used to examine the mRNA expression of integrin. A transient transfection protocol was used to examine NF‐κB activity.

RESULTS

We found that adiponectin increased the migration and the expression of α5β1 integrin of human prostate cancer cells. Adiponectin‐mediated migration and integrins expression was attenuated by p38 inhibitor (SB203580), p38 mutant, AMPK siRNA, AMPK inhibitor (araA and compound C). Activations of p38, AMPK and NF‐κB pathways after adiponectin treatment was demonstrated, and adiponectin‐induced expression of integrins and migration activity was inhibited by the specific inhibitor and mutant of p38, AMPK, and NF‐κB cascades.

CONCLUSIONS

This study showed for the first time that the adiponectin mediates migration of human prostate cancer cells. One of the mechanisms underlying adiponectin directed migration was transcriptional up‐regulation of α5β1 integrin and activation of AdipoR1 receptor, p38, AMPK, and NF‐κB pathways. Prostate 69: 1781–1789, 2009. © 2009 Wiley‐Liss, Inc.
Comparative theoretical study of small Rhn nanoparticles (2 ≤ n ≤ 8) using DFT methods
Authors: Bertin V. , Lopez‐Rendón R. , del Angel G. , Poulain E. , Avilés R. , Uc‐Rosas V.
Published: August 2009

This work is aimed at identifying some key characteristics (energy, geometry, and spin) concerning Rhn particles (2 = n ≤ 8) to perform further studies on adsorption and coadsorption sites of pollutants (CO and NO). The DFT methods of the Gaussian 03 program with the LANL2DZ basis set and the LANL2 potential are used. With the purpose to obtain a better nanoparticles definition, five different functionals were tested: B3LYP, O3LYP, BPW91, BP86, and HCTH; and the corresponding results are used to determine which of them best describes distances, spin, and gives acceptable highest vibration frequency and binding energy values, by comparing these results with values measured or calculated by many other authors. For the structure optimization process of the particles, the initial geometric shape was taken mainly from the literature, using the Rh–Rh distance: 2.67 Å, known for the bulk; and doing a complete optimization. We also considered flat nanoparticles structures, which most of them display three‐dimensional structures after the optimization process. The few flat shapes are mainly higher in energy than those of three‐dimensional structure. For some Rhn particles for different n values, the spin of the ground state present degeneration. In some cases, the optimization process changes the initial geometry, but in most cases, there are only minor changes in bonds and geometry. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Collective properties and combined quantum transitions of two‐dimensional magnetoexcitons
Authors: Moskalenko S. A. , Liberman M. A. , Dumanov E. V. , Podlesny I. V.
Published: August 2009

The article consists of two parts describing two associated properties of two‐dimensional magnetoexcitons. In the first part, the theory of combined exciton‐cyclotron resonance in the quantum well structures is developed for a strong magnetic field. In the first part, we calculate the absorption band structure for optical quantum transitions with circularly polarized radiation creating a two‐dimensional exciton and simultaneously exciting one of the resident electrons from the lowest to the first excited Landau level. In the second part, we discuss the collective elementary excitations of the system of two‐dimensional magnetoexcitons in the ground state of Bose–Einstein condensation on the arbitrary wave vector $\mathop K\limits^ \to$ ≠ 0 in the Hartree–Fock approximation. The breaking of the gauge symmetry of the initial Hamiltonian was introduced following the idea proposed by Bogoliubov in his theory of quasi‐averages. The energy spectrum of the collective elementary excitations is characterized by the interconnection of the exciton and plasmon branches. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Electrostatically driven complexes of SiF4 with amines
Authors: Politzer Peter , Murray Jane S. , Lane Pat , Concha Monica C.
Published: August 2009

Some SiF4·polyamine complexes that have recently been prepared are investigated computationally and compared to their counterparts involving NH3. The formation of these systems can be explained satisfactorily in terms of electrostatic interactions between positive σ‐holes on the silicon, on the extensions of the FSi bonds, and the lone pairs of the amino nitrogens. The displacement of an F− ion en route to complexes with three amino groups can be understood as a means of avoiding an excessive and destabilizing accumulation of negative charge in the central portion of the system. Very good overall agreement is found between crystallographic and the corresponding computed structural data. The σ‐hole interpretationa is fully compatible with initial sp3 → d2sp3 rehybridization of the silicon, but it is not necessary to invoke the latter. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Mass spectrometric analysis of peptides from an immobilized lipase: focus on oxidative modifications
Authors: Törnvall Ulrika , Fürst Camilla Melin , Hatti‐Kaul Rajni , Hedström Martin
Published: August 2009

Liquid chromatography/tandem mass spectrometry (LC/MS/MS) was used to study the primary structure of immobilized Candida antarctica lipase B (Novozym®435) without detaching the enzyme from the carrier. The immobilized enzyme packed in a miniature column was subjected to proteolysis and the peptides released were injected into the mass spectrometer for analysis. The set‐up was utilized to determine amino acid oxidation after treatment of the biocatalyst with hydrogen peroxide. In total, sequence coverage of more than 90% was obtained, containing almost all of the amino acids sensitive to oxidation. Oxidation of methionine, tryptophan and cystine residues was observed. The flow system also allowed evaluation of the enzyme activity prior to peptide analysis. The developed method is general and should be applicable to other immobilized enzyme systems and to different treatments. Copyright © 2009 John Wiley & Sons, Ltd.
Diastereomeric differentiation of norbornene amino acid peptides by electrospray ionization tandem mass spectrometry
Authors: Raju B. , Ramesh V. , Sudhakar A. , Ramesh M. , Sarma V. U. M. , Chandrasekhar S. , Srinivas R.
Published: August 2009

A new class of diastereomeric pairs of non‐natural amino acid peptides derived from butyloxycarbonyl (Boc‐)protected cis‐(2S,3R)‐ and trans‐(2S,3S)‐β‐norbornene amino acids including a monomeric pair have been investigated by electrospray ionization (ESI) tandem mass spectrometry using quadrupole time‐of‐flight (Q‐TOF) and ion‐trap mass spectrometers. The protonated cis‐BocN‐β‐nbaa (2S,3R) (1) (βnbaa = β‐norbornene amino acid) eliminates the Boc group to form [M+H–Boc+H]+, whereas an additional ion [M+H–C4H8]+ is formed from trans‐BocN‐β‐nbaa (2S,3S) (2). Similarly, it is observed that the peptide diastereomers (di‐, tri‐ and tetra‐), with cis‐BocN‐β‐nbaa (2S,3R)‐ at the N‐terminus, initially eliminate the Boc group to form [M+H–Boc+H]+ which undergo further fragmentation to give a set of product ions that are different for the peptides with trans‐BocN‐β‐nbaa (2S,3S)‐ at the N‐terminus. Thus the Boc group fragments differently depending on the configuration of the amino acid present at the N‐terminus. It is also observed that the peptide bond cleavage in these peptides is less favoured and most of the product ions are formed due to retro‐Diels‐Alder fragmentation. Interestingly, sodium‐cationized peptide diastereomers mainly yield a series of retro‐Diels‐Alder fragment ions which are different for each diastereomer as they are formed starting from [M+Na–Boc+H]+ in peptides with cis‐BocN‐β‐nbaa (2S,3R)‐ at the N‐terminus, and [M+Na–C4H8]+ in peptides with trans‐BocN‐β‐nbaa (2S,3S)‐ at the N‐terminus. All these results clearly indicate that these diastereomeric pairs of peptides yield characteristic product ions which help distinguish the isomers. Copyright © 2009 John Wiley & Sons, Ltd.
Application of hyphenated mass spectrometry techniques for the analysis of urinary free glucocorticoids
Authors: Cuzzola Angela , Petri Antonella , Mazzini Francesco , Salvadori Piero
Published: August 2009

Alteration of levels of glucocorticoids in plasma and urine can be related to several diseases. In particular, the determination of endogenous glucocorticoids in urine has been reported to provide information on cortisol and cortisone status, on the activities of steroid hormone enzymes and on glucocorticoid metabolism. In this study, the application of hyphenated mass spectrometry techniques (GC/MS without derivatization and LC/MS) for the simultaneous analysis of free urinary cortisol (F), cortisone (E), tetrahydrocortisol (THF), allo‐tetrahydrocortisol (A‐THF) and tetrahydrocortisone (THE) was evaluated. A sample preparation protocol by solid‐phase extraction, mass spectrometry parameters and chromatographic conditions for both techniques were carefully optimized in terms of extracting phase and solvents, matrix effects, recovery, sensitivity and compound resolution. Baseline separation was achieved for the five underivatized analytes both in GC and LC. The LC/MS/MS technique was more suitable for the analysis of urine samples, being less influenced by matrix effects and showing excellent sensitivity and selectivity. A preliminary application of the reported method for the diagnosis of metabolic diseases was also described. The determination of each analyte in its free form, described for the first time in the paper, offers new perspectives in the application of glucocorticoid analysis for diagnostic purposes. Copyright © 2009 John Wiley & Sons, Ltd.
On multiple‐delay output feedback stabilization of LTI plants
Authors: Roy Sandip , Saberi Ali , Wan Yan
Published: August 2009

We develop a control methodology for linear time‐invariant plants that uses multiple delayed observations in feedback. Using the special coordinate basis, we show that multiple‐delay controllers can always be designed to stabilize minimum‐phase plants, and identify a class of non‐minimum‐phase plants that can be stabilized using these controllers. Copyright © 2009 John Wiley & Sons, Ltd.
Time course analysis of microarray data for the pathway of reproductive development in female rainbow trout
Authors: Liu Y. , Verducci J. , Schultz I. , Hook S. , Nagler J. , Craciun G. , Sundling K. , Hayton W.
Published: August 2009

New statistical procedures are introduced to investigate gene activity in support of the hypothalamus–pituitary–gonad–liver signaling network that provides the neuroendocrine regulation for reproduction in female, oviparous fishes. The methods include Shrunken Centroid Ordering by Orthogonal Projections (SCOOP) and a robust encoding of B‐splines via Friedman's Generalized Elastic Net (GEN). SCOOP orders genes according to a novel criterion that balances discriminatory and correlative information. It is particularly useful in the present context where genes are only partially annotated, relevant networks are not known a priori, and the sample size is adequate for finding natural clusters. In this application, microarray measurements of gene expression were made in the pituitary, liver, and ovary of female rainbow trout (Oncorhynchus mykiss) over the course of their 1 year spawning cycle, and new methods were developed to detect systematic changes in potential gene networks. B‐splines were fitted to gently smooth the estimates of expression versus time and provide a common framework for analysis. Unlike other methods, SCOOP selected not only the genes whose curves vary the most over time, but also genes closely correlated with these. This tended to recognize genes that may be part of an active network, but whose expressions undergo more modest fluctuations. To compensate for the high degree of uncertainty in fitting B‐splines to individual genes, GEN methods were used to provide robust fits, and these were summarized through a novel GEN‐transform as variable importance measures (VIMs). Clustering of genes via VIMs produced much more stable results than directly via B‐spline coefficients, and the mean time course pattern of each cluster provided biologists with a reliable summary from which to interpret systematic patterns. Ultimately, the genes selected by SCOOP and clustered though the GEN‐transform strongly suggested supportive pathways involving immunology, muscle contraction, reproduction, protein transport, metabolism, and reduction/oxidation. Copyright © 2009 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 2: 192–208, 2009
Mental retardation and inborn errors of metabolism
Authors: García‐Cazorla A. , Wolf N. I. , Serrano M. , Moog U. , Pérez‐Dueñas B. , Póo P. , Pineda M. , Campistol J. , Hoffmann G. F.
Published: August 2009

In countries where clinical phenylketonuria is detected by newborn screening inborn errors of metabolism are rare causes of isolated mental retardation. There is no international agreement about what type of metabolic tests must be applied in patients with unspecific mental retardation. However, and although infrequent, there are a number of inborn errors of metabolism that can present in this way. Because of the high recurrence risk and the possibility of specific therapies, guidelines need to be developed and adapted to different populations. The application of a universal protocol may result in a low diagnostic performance in individual ethnic populations. Consideration of associated signs (extraneurological manifestations, psychiatric signs, autistic traits, cerebellar dysfunction, epilepsy or dysmorphic traits) greatly improves the diagnostic fulfilment.
Relation of Supersaturation Ratio in Mixed Anionic Surfactant Solutions to Kinetics of Precipitation with Calcium
Authors: Soontravanich Sukhwan , Scamehorn John F.
Published: August 2009

One synergism of using surfactant mixtures is the reduction in the equilibrium extent of and rate of precipitation. The overall time required for calcium‐induced precipitation of mixed sodium dodecyl sulfate (SDS) and sodium octylbenzene sulfonate (SOBS) over a particular range of ratios has been found to increase dramatically when compared to either SDS or SOBS alone. In this study, light transmission and isoperibol calorimetry were used to measure the delay in the precipitation reaction, while scanning electron and optical micrographs of crystals formed give insight into the precipitation mechanism. The smaller the difference in the supersaturation ratio of the two precipitating surfactants, the longer the induction time is. The delay in the extent of precipitation is due to the interruption of crystal formation from dissimilar precipitating surfactants.
Characterization of Olive‐Leaf Phenolics by ESI‐MS and Evaluation of their Antioxidant Capacities by the CAT Assay
Authors: Laguerre Mickaël , Lόpez Giraldo Luis Javier , Piombo Georges , Figueroa‐Espinoza Maria Cruz , Pina Michel , Benaissa Mohamed , Combe Aurélia , Rossignol Castera Anne , Lecomte Jérôme , Villeneuve Pierre
Published: August 2009

Olive leaves are a very abundant vegetable material containing various phenolic compounds, such as secoiridoids and flavonoids, that are expected to exert strong antioxidant capacity. However, little is known about the variation of olive‐leaf phenolic composition during maturation and its influence on antioxidant capacity. To answer this question, young and mature Olea Europaea L. leaves were submitted to successive extraction with dichloromethane, ethyl acetate, and methanol, then characterized by ESI‐MS. It appeared that mature olive‐leaf extracts contained higher levels of verbascoside isomers and glucosylated forms of luteolin, while young ones presented higher contents of oleuropein, ligstroside, and flavonoid aglycones. Moreover, antioxidant capacity evaluation using our newly developed conjugated autoxidizable triene assay showed that, in a lipid‐based emulsified system, this phenolic composition variation leads to a change in the ability of extracts to counteract lipid oxidation. Mature olive‐leaf extracts exhibit higher antioxidant capacity than young olive‐leaf extracts. This result enables us to hypothesize that two main bioconversion scenarios may occur during maturation of olive leaves, which could explain changes observed in antioxidant capacity: (1) a bioconversion of oleuropein and ligstroside into verbascoside isomers and oleuroside, and (2) a bioconversion of flavonoid aglycones into glucosylated forms of luteolin. Finally, this study leads to a better understanding of the relationship between phenolic profile and antioxidant capacity of olive leaves.
The Constraining Capacity of Legal Doctrine on the U.S. Supreme Court
Authors: BARTELS BRANDON L.
Published: August 2009

Does law exhibit a significant constraint on Supreme Court justices' decisions? Although proponents of the attitudinal model argue that ideology predominantly influences justices' choices, “hybrid models” posit that law and ideology exhibit discrete and concurrent effects on justices' choices. I offer a new conceptualization of legal constraint examining how legal rules permit varying degrees of ideological discretion, which establishes how strongly ideological preferences will influence justices' votes. In examining the levels-of-scrutiny legal doctrine, I posit theoretical models highlighting the differential constraining capacities of the strict scrutiny, intermediate scrutiny, and rational basis rules. I use a multilevel modeling framework to test the hypotheses within the context of theGrayneddoctrine in free expression law. The results show that strict scrutiny, whichGraynedapplied to content-based regulations of expression, significantly constrains ideological voting, whereas intermediate scrutiny (applied to content-neutral regulations) and the low scrutiny categories each promote high levels of ideological voting.
A CONLEY INDEX CALCULATION
Authors: DANCER E. N.
Published: August 2009

We discuss a Conley index calculation which is of importance in population models with large interaction. In particular, we prove that a certain Conley index is trivial.
Intervention with fish oil, but not with docosahexaenoic acid, results in lower levels of hepatic soluble epoxide hydrolase with time in apoE knockout mice
Authors: Mavrommatis Yiannis , Ross Karen , Rucklidge Garry , Reid Martin , Duncan Gary , Gordon Margaret-Jane , Thies Frank , Sneddon Alan , de Roos Baukje
Published: August 2009

Long-chainn-3 PUFA from fish oil protect against death from CHD but mechanisms are not well understood. Preliminary results indicate that fish oil may affect the enzyme soluble epoxide hydrolase (sEH) and influence inflammatory pathways in a time-dependent manner. In the present study male apoE knockout (Apoe− / − ) mice were randomised to three dietary groups receiving a high-fat high-cholesterol diet supplemented with 2 % (w/w) high-oleic acid sunflower-seed (HOSF) oil, DHA oil or fish oil. Livers and proximal aortas were collected on day 2 and on weeks 1, 2, 4 and 10 to determine hepatic sEH levels, hepatic fatty acid composition, hepatic proteome and atherosclerotic plaque size in the aortic root. Intervention with fish oil, but not with DHA, resulted in significantly lower levels of hepatic sEH levels with time compared with HOSF oil. DHA and fish oil caused differential regulation of thirty-five hepatic proteins which were mainly involved in lipoprotein metabolism and oxidative stress. All mice developed atherosclerosis without differences in plaque size between the three groups. Thus EPA may be responsible for lowering levels of hepatic sEH and both fish oil and DHA could beneficially affect lipoprotein metabolism and oxidative stress.
Subshifts on surfaces
Authors: Fried David
Published: August 2009

We determine when a polynomial is the reduced zeta function of a basic set of a Smale diffeomorphism of a compact surface.
An ε-free Rohlin lemma
Authors: Lehrer Ehud , Weiss Benjamin
Published: August 2009

For an ergodic transformation T, necessary and sufficient conditions are given for a set A and an integer n so that the existence of a set B with pairwise disjoint and is ensured.
LOCAL ASYMPTOTIC POWER OF THE IM-PESARAN-SHIN PANEL UNIT ROOT TEST AND THE IMPACT OF INITIAL OBSERVATIONS
Authors: Harris David , Harvey David I. , Leybourne Stephen J. , Sakkas Nikolaos D.
Published: August 2009

In this note we derive the local asymptotic power function of the standardized averaged Dickey–Fuller panel unit root statistic of Im, Pesaran, and Shin (2003, Journal of Econometrics, 115, 53–74), allowing for heterogeneous deterministic intercept terms. We consider the situation where the deviation of the initial observation from the underlying intercept term in each individual time series may not be asymptotically negligible. We find that power decreases monotonically as the magnitude of the initial conditions increases, in direct contrast to what is usually observed in the univariate case. Finite-sample simulations confirm the relevance of this result for practical applications, demonstrating that the power of the test can be very low for values of T and N typically encountered in practice.
Profiles of levels of lipids and dyslipidaemia in children from Beijing, China
Authors: Hui Yan , Jie Mi , Ying Liu , Hongfang Jin , Li Chen , Chaoshu Tang , Junbao Du
Published: August 2009

Background

There is limited data available on characteristics of profiles of lipids in children. The purpose of our investigation, therefore, was to determine the lipid profile, and analyze the prevalence of dyslipidaemia, in subgroups of children according to different gender, districts of residence, and ages in Beijing, China.

Methods and Results

We included 18,944 school children, aged from 7 to 18 years, in our community-based cross-sectional study, measuring the levels of total cholesterol and triglyceride in capillary blood, and at the same time determining their weight and height. Weights, heights, circumference at the waist, and body mass index proved to be significantly greater for the boys than the girls. The levels of total cholesterol of boys and girls were 3.98 ± 0.35, and 4.02 ± 0.35 mmol/L, respectively, while the comparable levels of triglycerides were 1.08 ± 0.52, and 1.18 ± 0.66 mmol/L, respectively. The percentages of hypercholesterolaemia, hypertriglyceridaemia, combined dyslipidaemia, and hyperlipidaemia were 1.2, 8.8, 0.4, and 9.7%, respectively. The incidences of hypertriglyceridaemia, combined dyslipidaemia, and hyperlipidaemia of girls were higher than boys. The levels of triglycerides for boys aged from 11 to 18 years living in an urban setting were higher than those for boys living in rural settings, as were the levels of total cholesterol for boys aged from 12 to 16 years.

Conclusion

Our study provides the newest current profiles of lipids for children living in Beijing. We found significant influences of age, districts of residence, and genders on the levels of lipids, features which need further attention in the prevention and treatment of dyslipidaemia.