bluuebunny/crossref_metadata_2025 huggingface dataset:
Thoracoscopic biopsy in children with diffuse parenchymal lung disease
Authors: Glüer Sylvia , Schwerk Nicolaus , Reismann Marc , Metzelder Martin L. , Nustede Rainer , Ure Benno M. , Gappa Monika
Published: September 2008

Lung biopsy is necessary for establishing the diagnosis in patients with otherwise unclassified diffuse or localized parenchymal lung disease. This study aimed to assess the safety and accuracy of video‐assisted thoracoscopic (VATS) lung biopsy in children with diffuse parenchymal lung disease (DPLD). In addition we aimed to evaluate the value of this technique with respect to the spectrum of diseases encountered, correlating histological diagnosis with treatment decisions and subsequent clinical outcome. Data from all patients (n = 21) who underwent surgical lung biopsy for suspected DPLD between March 2001 and August 2006 were collected prospectively. Median age was 3 years, 8 months (range 11 days to 15 years, 2 months). All lung biopsies were performed by VATS under general anesthesia. Median operative time was 45 min (range 25–100 min). Conversion to minithoracotomy due to cardiorespiratory difficulties was necessary in two young infants. There were no further intraoperative complications. In 8/21 children, a chest tube was inserted postoperatively for a median of 2 days (range 1–5 days). In one patient, prolonged air‐leakage was managed thoracoscopically on postoperative day 9. There were no other postoperative complications. The specimens were of adequate volume and quality and a histopathological diagnosis was obtained for all patients. There was a broad spectrum of different diagnoses which led to specific therapeutic decisions. Subsequent medical treatment was beneficial in the majority of the patients. In conclusion, VATS is a safe and effective procedure for diagnosis of children with suspected DPLD. Diagnostic accuracy is high, morbidity rates are low, and patients may benefit from avoiding thoracotomy. Pediatr Pulmonol. 2008; 43:992–996. © 2008 Wiley‐Liss, Inc.
Wilson–Mikity syndrome: Updated diagnostic criteria based on nine cases and a review of the literature
Authors: Hoepker Amy , Seear Michael , Petrocheilou Argyri , Hayes Don , Nair Arun , Deodhar Jayant , Kadam Sandeep , O'Toole John
Published: September 2008

Background

Nearly 50 years ago, Wilson and Mikity described a syndrome (WMS) of chronic lung disease (CLD) in premature infants, characterized by early development of cystic interstitial emphysema (PIE), despite minimal ventilatory support. The validity of the diagnosis is currently unclear; now considered either an anachronism, part of BPD spectrum or included within various poorly defined diagnoses such as chronic pulmonary insufficiency of prematurity (CPIP).

Objectives

To define clinically useful diagnostic criteria for WMS so its position in the spectrum of CLD of infancy can be established.

Methods

We studied nine patients who fulfilled WMS criteria, combining this data with a detailed review of the available literature.

Results

Despite minimal respiratory support at birth, all developed generalized or lobar cystic PIE by 3 weeks of age, followed by slow inflammatory progression over a further 2–3 months. Final outcome was variable but most were left with some degree of CLD.

Conclusions

WMS is a rare but clearly identifiable syndrome with significant morbidity, predominantly affecting infants below 1,500 g birth weight. The earliest pathology appears to be alveolar air leak. Inflammatory activation induced by cystic interstitial air may cause the subsequent progressive respiratory disease. Management is supportive but should include investigation for pulmonary hypertension. Pediatr Pulmonol. 2008; 43:1004–1012. © 2008 Wiley‐Liss, Inc.
Assessment of body composition in pediatric patients with cystic fibrosis
Authors: Wells Greg D. , Heale Liane , Schneiderman Jane E. , Wilkes Donna L. , Atenafu Eshetu , Coates Allan L. , Ratjen Felix
Published: September 2008

Rationale

Cystic fibrosis (CF) leads to pathological changes in organs that express the cystic fibrosis transmembrane conductance regulator (CFTR), including secretory cells of the digestive tract and the pancreas. Maintaining nutritional sufficiency is challenging for CF patients and therefore accurate monitoring is important for their clinical management.

Purpose

The objectives of this study were to evaluate the effectiveness of skinfold measurements as an accurate method for determining body composition (fat mass (FM) and lean body mass (LBM)) of this population, using dual‐energy X‐ray absorptiometry (DEXA) as a gold standard comparison and to determine the most accurate equation for this calculation in children with CF.

Methods

Fifty‐five pediatric patients with CF participated in the study. FM and LBM calculated via four methods: Slaughter, Durnin, Durenberg (2‐site and 4‐site). The relationship between the methods and DEXA results were estimated by intraclass‐correlation coefficient (ICC) and Bland and Altman analyses.

Results

The Slaughter method was the most accurate (ICC of 0.92 for FM and 0.99 for LBM) and displayed the least bias over the range of FM and LBM in CF patients. In addition, the results of Bland Altman analyses comparing each skinfold method to DEXA, revealed that the results were evenly distributed along the range of values for the Slaughter calculation, whereas the other three methods under and over estimated % fat results at the upper and lower ends of the range respectively.

Conclusion

We therefore conclude that the Slaughter method may be used for body composition assessment of pediatric CF patients. This provides clinical teams with a simple, accurate and non‐invasive method that can be used to monitor nutritional status in pediatric patients with CF. Pediatr Pulmonol. 2008; 43:1025–1032. © 2008 Wiley‐Liss, Inc.
An Ab Initio Theoretical Study of 2,4,6‐Trinitro‐1,3,5‐Triazine, 3,6‐Dinitro‐1,2,4,5‐Tetrazine, and 2,5,8‐Trinitro‐Tri‐s‐Triazine
Authors: Li Jinshan
Published: September 2008

In order to evaluate 2,4,6‐trinitro‐1,3,5‐triazine (TNTAz), 3,6‐dinitro‐1,2,4,5‐tetrazine (DNTAz), and 2,5,8‐trinitro‐tri‐s‐triazine (TNTsTAz), the geometries of these compounds have been fully optimized employing the B3LYP density functional method and the AUG‐cc‐pVDZ basis set. The accurate gas phase enthalpies of formation have been obtained by using the atomization procedure and designing isodesmic reactions in which the parent rings are not destroyed. Based on B3LYP/AUG‐cc‐pVDZ calculated geometries and natural charges, the crystal structures have been predicted using the Karfunkel–Gdanitz method. Computed results show that there exists extended conjugation over the parent rings of these compounds. More energy content is reserved in DNTAz than in both TNTAz and TNTsTAz. The title compounds are much more sensitive than 1,3,5‐trinitrobenzene. The calculated detonation velocity of DNTAz reaches 9.73–9.88 km s−1, being larger than those of CL‐20 and TNTAz. TNTsTAz has no advantage over the widely used energetic compounds such as RDX and HMX.
Synthesis and Characterization of Glycidyl Azide‐r‐(3,3‐bis(azidomethyl)oxetane) Copolymers
Authors: Kawamoto Aparecida M. , Holanda J. A. Saboia , Barbieri Ugo , Polacco Giovanni , Keicher Thomas , Krause Horst , Kaiser Manfred
Published: September 2008

Glycidyl azide‐r‐(3,3‐bis(azidomethyl)oxetane) copolymers were synthesized by cationic copolymerization of epichlorohydrin and 3,3‐bis(bromomethyl)oxetane, using butane‐1,4‐diol as an initiator and boron trifluoride etherate as a catalyst, followed by azidation of the halogenated copolymer. The main objective of this work is the preparation of an OH‐terminated amorphous polymer with energetic content higher than that of the well‐known glycidyl azide homopolymer. The effect of experimental conditions, i.e., the rate of monomer feeding, on the final molecular weight and functionality of the copolymer has also been investigated. The obtained copolymers were extensively characterized to determine their composition and thermal stability. The heat of reaction for the polymerization of the halogenated key precursors has also been measured. It was found that even though both the operating conditions and the catalytic system were chosen in order to favor a living character of the polymerization, the final product seems to be the result of a combined living and active chain end mechanism. In particular, the latter is responsible for the formation of oligomers and not hydroxyl‐terminated chains. Nevertheless, the average number of OH groups is high enough to allow a cross‐linking of the polymeric chains, by addition of polyisocyanates and subsequent formation of inter‐chain urethanic bonds.
Combustion Behaviour of Melt‐Castable Explosives from Azetidine Family
Authors: Sinditskii Valery P. , Egorshev Viacheslav Y. , Berezin Maxim V. , Rudakov Gennady F. , Ladonin Alexander V. , Katorov Dmitriy V.
Published: September 2008

Combustion behaviours of melt‐castable explosives from azetidine family, 1,3,3‐trinitroazetidine (TNAZ), 3‐azido‐1‐nitroazetidine (AZNAZ) and 3‐azido‐1,3‐dinitroazetidine (AZDNAZ) have been studied. Burning rate measurements have been performed in a constant‐pressure bomb in the pressure range of 0.1–30 MPa. A pressure interval has been found within which pressed AZNAZ samples were incapable of sustained burning. Temperature profiles in the combustion wave of TNAZ, AZDNAZ and AZNAZ were measured using thin tungsten–rhenium thermocouples. Thermocouple‐aided measurements allowed the determination of the temperature dependence of TNAZ and AZDNAZ vapour pressure in a wide temperature interval, the boiling points at atmospheric pressure and the heat of evaporation. Combustion mechanisms of the energetic materials studied are discussed.
The Low‐Temperature High‐Pressure Phase Diagram of Energetic Materials: I. Hexahydro‐1,3,5‐Trinitro‐s‐Triazine
Authors: Ciezak Jennifer A. , Jenkins Timothy A.
Published: September 2008

The reaction phase diagram of hexahydro‐1,3,5‐trinitro‐s‐triazine (RDX) has been studied as a function of temperature and pressure by Raman spectroscopy to 29 GPa and temperatures ranging from 4 to 298 K. Three stable phases (α, γ, and δ) have been found and their phase stabilities have been investigated. Phase boundaries were studied as a function of pressure and temperature, permitting a delineation of the various polymorph stability fields. A pressure–temperature reaction/phase diagram is constructed from the results of this study and compared to previous high temperature work.
Molecular analysis of multifocal prostate cancer by comparative genomic hybridization
Authors: Kobayashi Masayuki , Ishida Haruna , Shindo Takayuki , Niwa Shin‐ichiro , Kino Mika , Kawamura Koji , Kamiya Naoto , Imamoto Takashi , Suzuki Hiroyoshi , Hirokawa Yoshifumi , Shiraishi Taizo , Tanizawa Tohru , Nakatani Yukio , Ichikawa Tomohiko
Published: September 2008

BACKGROUND

Prostate cancer is often multifocal and shows histological heterogeneity among different tumor foci within the same prostate. We analyzed the origin and molecular basis of multifocal prostate cancer and genomic alterations associated with tumor progression.

METHODS

We examined 45 multifocal prostate cancer foci from 22 radical prostatectomy specimens by comparative genomic hybridization (CGH). Laser capture microdissection (LCM) was used to gather cancer cells from frozen prostate specimens.

RESULTS

Frequent chromosomal alternations were losses of 2q21–24 (22.2%), 6q14‐22 (60.0%), 8p12–22 (35.6%), 13q14–31 (44.4%) and 16q13–24 (24.4%) and gains of 8q21.3–24.3 (37.8%) and 7q21–33 (20.0%). Frequency of losses of 8p12–22 and 16q13–24 and gains of 8q21.3–24.3 were significantly higher in tumors with high Gleason score (GS) than in those with low GS (P < 0.01, P < 0.05, and P < 0.01, respectively). Tumors with losses of 8p12–22 or 13q14–31 displayed larger volume than those without such losses (P < 0.05 and P < 0.01, respectively). In comparison between different tumor foci within the same prostate, chromosomal alterations did not show completely the same pattern between any tumor foci, except for one case in which two of the three foci displayed no chromosomal abnormalities. More malignant tumors (high GS or extracapsular invasion) displayed significantly higher frequency of losses of 8p12–22 (P < 0.05).

CONCLUSIONS

These results suggest that tumor foci within the same prostate represent independent tumors with differing clonal origin and that loss of 8p12–22 represents an important determinant of prostate cancer progression. Prostate © 2008 Wiley‐Liss, Inc.
NF‐κB2/p52 enhances androgen‐independent growth of human LNCaP cells via protection from apoptotic cell death and cell cycle arrest induced by androgen‐deprivation
Authors: Nadiminty Nagalakshmi , Chun Jae Yeon , Lou Wei , Lin Xin , Gao Allen C.
Published: September 2008

PURPOSE

Androgen‐deprivation therapy only causes a temporary regression of prostate cancer, as all tumors will eventually progress to refractory to hormonal therapy after 1–3 years of treatment. The underlying mechanisms of prostate cancer androgen refractory progression are incompletely understood. In this study, we employed in vitro as well as in vivo models to examine the role of NF‐κB2/p52 in prostate cancer growth and androgen independent progression.

EXPERIMENTAL DESIGN

The effects of NF‐κB2/p52 on cell growth, androgen responsiveness, cell cycle and apoptosis were examined in androgen sensitive LNCaP cells. The effect of NF‐κB2/p52 on tumor growth was examined in intact and castrated male mice.

RESULTS

Overexpression of NF‐κB2/p52 enhances androgen‐sensitive LNCaP human prostate cancer cell growth and clonogenic ability in androgen‐deprived condition in vitro. NF‐κB2/p52 induced androgen‐independent growth is through protecting LNCaP cells from apoptotic cell death and cell cycle arrest induced by androgen‐deprivation. In addition, NF‐κB2/p52 stimulates Cyclin D1 expression and knock down of Cyclin D1 expression by siRNA abolished NF‐κB2/p52‐induced cell growth in vitro. Adenoviral mediated NF‐κB2/p52 expression in LNCaP cells enhances tumor growth in intact male nude mice and induces tumor growth in castrated male nude mice, suggesting that overexpression of NF‐κB2/p52 induces androgen‐independent growth of androgen‐sensitive LNCaP cells.

CONCLUSIONS

Overexpression of NF‐κB2/p52 protects androgen sensitive LNCaP cells from apoptotic cell death and cell cycle arrest induced by androgen‐deprivation. NF‐κB2/p52 activation induces androgen‐independent growth in vitro and in vivo. Prostate © 2008 Wiley‐Liss, Inc.
In pursuit of virtual lead optimization: Pruning ensembles of receptor structures for increased efficiency and accuracy during docking
Authors: Bolstad Erin S. D. , Anderson Amy C.
Published: September 2008

Representing receptors as ensembles of protein conformations during docking is a powerful method to approximate protein flexibility and increase the accuracy of the resulting ranked list of compounds. Unfortunately, docking compounds against a large number of ensemble members can increase computational cost and time investment. In this article, we present an efficient method to evaluate and select the most contributive ensemble members prior to docking for targets with a conserved core of residues that bind a ligand moiety. We observed that ensemble members that preserve the geometry of the active site core are most likely to place ligands in the active site with a conserved orientation, generally rank ligands correctly and increase interactions with the receptor. A relative distance approach is used to quantify the preservation of the three‐dimensional interatomic distances of the conserved ligand‐binding atoms and prune large ensembles quickly. In this study, we investigate dihydrofolate reductase as an example of a protein with a conserved core; however, this method for accurately selecting relevant ensemble members a priori can be applied to any system with a conserved ligand‐binding core, including HIV‐1 protease, kinases, and acetylcholinesterase. Representing a drug target as a pruned ensemble during in silico screening should increase the accuracy and efficiency of high‐throughput analyses of lead analogs. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Influence of the supporting salt concentration on the electrodeposition of ZnO/eosin Y hybrid films
Authors: Boeckler C. , Oekermann T. , Saruban M. , Ichinose K. , Yoshida T.
Published: September 2008

ZnO/eosin Y hybrid films were electrodeposited from O2‐saturated ZnCl2‐solution under variation of the concentration of the supporting salt KCl. The supporting salt concentration was found to have a significant influence on the amount of dye loading and the morphology of the ZnO/eosin Y films. By decreasing the supporting salt concentration to 0.01 M KCl, porous films with a high dye loading can be obtained at potentials of –0.8 V vs. SCE at low eosin Y concentrations in the electrodeposition bath, which usually only lead to porous films at potentials where eosin Y is reduced (< –0.9 V vs. SCE). (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrochemical synthesis of macroporous zinc oxide layers by employing hydrogen peroxide as oxygen precursor
Authors: Ramirez Daniel , Bartlett Philip , Abdelsalam Mamdouh , Gomez Humberto , Lincot Daniel
Published: September 2008

Two‐ and three‐dimensional ordered porous zinc oxide (ZnO) films were prepared by electrodeposition on Indium Tin Oxide coated glass, using two‐ and three‐dimensional poly(styrene) opal templates. The oxide was formed by electrochemical reduction of hydrogen peroxide in aqueous zinc perchlorate solution. Scanning electron microscopy measurements showed well ordered inverse opal structures for macroporous ZnO. At high hydrogen peroxide concentration, dense inner conformal filling was achieved for 2D and 3D structures. The formation of nanocrystalline ZnO was checked by X‐ray diffraction. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In‐situ observation on Raman spectra and transport properties of single‐wall carbon nanotubes
Authors: Liang Chen‐Wei , Lee Wei‐Yang , Tsai Cheun‐Horng , Roth Siegmar
Published: September 2008

An experimental study combining Raman spectra and transport measurements on single‐walled carbon nanotubes (SWNTs) is reported. Two SWNT ropes are monitored by Raman spectroscope while applying constant current. The application of the current causes a reduction of G‐band intensity in the Raman spectra of one of the devices while the other shows no effect. A model based on the self‐heating of the nanotubes is proposed to explain the observed phenomenon. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Drift effect of fluctuation enhanced gas sensing on carbon nanotube sensors
Authors: Heszler Peter , Gingl Zoltan , Mingesz Robert , Csengeri Attila , Haspel Henrik , Kukovecz Akos , Kónya Zoltan , Kiricsi Imre , Ionescu Radu , Mäklin Jani , Mustonen Tero , Tóth Géza , Halonen Niina , Kordás Krisztián , Vähäkangas Jouko , Moilanen Hannu
Published: September 2008

A low‐noise electronic system is built and tested for fluctuation enhanced sensing. This latter is a new technique and based on the determination of the power spectral density of the stationary resistance fluctuations of semiconductor gas sensors. Its use is advantageous for improving the chemical selectivity of sensors. However, subsequent to an initial fast change of the sensor mean resistance, as a sensor is exposed to an analyte gas, a typical drift of the resistance can be observed. This effect hinders evolving stacionary conditions and thus acquiring fast measurements when applying fluctuation enhanced sensing. Therefore, this drift effect is studied both experimentally and theoretically. Functionalized carbon nanotube layers on silicon chips serve as active material for the experimental investigations. Power spectral density functions are measured and simulated numerically with and without drift conditions. The results are compared and the effect of resistive drift on fluctuation enhanced sensing is discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the catalyst drying process and catalyst support particle size on the carbon nanotubes produced by CCVD
Authors: Mionic’︁ Marijana , Alexander Duncan T. L. , Forró László , Magrez Arnaud
Published: September 2008

Catalytic Chemical Vapour Deposition (CCVD) is considered as the most suitable technique for the large scale and low‐cost production of multiwalled carbon nanotubes. We have studied the effect of the preparation process, and of the support particle size on the catalyst efficiency, conversion yield of the carbon source and diameter of the nanotubes produced. When 50 nm calcite CaCO3 particles support the Fe2Co nanoparticles and when the catalyst is freeze dried to avoid the particles agglomeration, 85% of acetylene is converted into MWCNTs; and by using our rotary tube furnace, 1200 g of MWCNTs can be produced per day. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Infrared spectroscopy on the fullerene C70 under pressure
Authors: Thirunavukkuarasu K. , Kuntscher C. A. , Borondics F. , Klupp G. , Kamarás K.
Published: September 2008

We present pressure‐dependent infrared transmittance measurements on fullerene C70 at room temperature in the pressure range up to 4 GPa. The vibrational modes of C70 exhibit a nearly linear pressure dependence with a sluggish anomaly at around 0.8 GPa. This anomaly could be attributed to the change in the orientational ordering of the C70 molecules. The sluggish character of the transition could be either due to the continuous change of the orientational order or the coexistence of two phases in the solid C70. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron transmission through step‐ and barrier‐like potentials in graphene ribbons
Authors: Klymenko Yuriy , Malysheva Lyuba , Onipko Alexander
Published: September 2008

The list of textbook tunneling formulas is extended by deriving exact expressions for the transmission coefficient in graphene ribbons with armchair edges and the step‐like and barrier‐like profiles of site energies along the ribbon. These expressions are obtained by matching wave functions at the interfaces between the regions, where quasiparticles have constant but different potential energies. It is shown that for an U0 high barrier and low‐energy electrons and holes, the mode transmission of charge carriers in this type of ribbons is described by the textbook formula, where the constant barrier is replaced by an effective, energy‐dependent barrier, U0 → U (E). For the lowest/highest electron/hole mode, U (E) goes, respectively, to zero and nonzero value in metallic and semiconducting ribbons. This and other peculiarities of through‐barrier/step transmission in graphene are discussed and compared with related earlier results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theoretical study of the electronic structure and the totally symmetric vibrations of selected CoMoCat carbon nanotubes
Authors: Kürti Jenő , Koltai János , Zólyomi Viktor
Published: September 2008

In situ Raman spectroelectrochemical studies of CoMo‐Cat single‐walled carbon nanotubes enriched in (6,5) tubes have been carried out recently. We performed calculations on the density functional level using local density approximation for the electronic and vibrational properties of the most abundant tubes in these samples. The following chiral semiconducting tubes were investigated: (6,4), (7,3), (6,5), (9,1), (8,3) and (7,5). The calculated and the measured frequencies of the RBM and G– modes agree within several wave numbers. The calculated E11, E22 transition energies ‐after 30% and 20% upscaling, respectively‐ are comparable with the experimental values. The quenching of the RBM band with p‐ and n‐doping can be interpreted within the rigid band approximation. The validity of the rigid band approximation was shown by calculating the density of states for neutral and charged tubes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Statistical analysis of atomic force microscopy and Raman spectroscopy data for estimation of graphene layer numbers
Authors: Obraztsova Ekaterina A. , Osadchy Alexander V. , Obraztsova Elena D. , Lefrant Serge , Yaminsky Igor V.
Published: September 2008

In this work we present the results on preparation and analysis of structural and electronic properties of graphene flakes with different number of layers. Since the material electronic properties depend strongly on the layer number, a simple and reliable way to estimate this parameter should be found. In this work we propose to perform a quantitative analysis based on the atomic force microscopy (AFM) which was exploited by another authors rather as an illustrative technique. The graphene flakes were prepared by a micromechanical cleavage of highly oriented pyrolytic graphite (HOPG). Numerous flakes have been studied with AFM in order to estimate the number of graphene layers in each of them. The thickness distribution over the individual graphene flake, averaged over the all flakes investigated, has exhibited a row of maxima: 0.7 nm, 1.1 nm, 1.4 nm, 1.7 nm, 2.1 nm, etc. These values correspond perfectly to the one‐, two, three‐, and etc layers of graphene. The flakes characterized by AFM were studied afterwards with a two‐phonon Raman spectroscopy. This method is known to be sensitive to the number of layers due to a “double resonance” mechanism. To interpret the Raman spectra the electronic structure of the graphene flakes of different thickness has been calculated using the density functional method. A perfect correspondence between the number of graphene layers in different flakes measured by AFM and by Raman techniques has been obtained. This demonstrates a possibility to estimate correctly the graphene layer number using the atomic force microscopy supplied with the statistical analysis. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Lattice anharmonicity in low‐dimensional carbon systems
Authors: Bonini Nicola , Rao Rahul , Rao Apparao M. , Marzari Nicola , Menéndez José
Published: September 2008

The anharmonic properties of low‐dimensional carbon crystal lattices are reviewed. The energy and crystal momentum conservation rules in two‐ and one‐dimensional crystals lead to a drastic reduction of the phase space available for anharmonic phonon decay. This is illustrated with first principles calculations of the anharmonic properties of graphite and graphene. Experimental Raman linewidth data for the Radial Breathing Mode (RBM) in suspended single‐walled carbon nanotubes are also interpreted in terms of a simple model in which a phonon decay bottleneck induced by the low dimensionality leads to a population time dependence in which a fast initial decay is followed by a slow decay determined by the decay rate of a large population of secondary phonons. These results are key to understanding the combined dynamics of electrons and phonons that determines the electrical transport properties in low‐dimensional carbon nanostructures. In the case of the RBM in carbon nanotubes, they raise the intriguing possibility of using the linewidth of the Raman peak to determine the chirality of the nanotube. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth characteristics of chloride‐based SiC epitaxial growth
Authors: Pedersen H. , Leone S. , Henry A. , Lundskog A. , Janzén E.
Published: September 2008

In this study some aspects of the chloride‐based CVD growth process have been investigated by using both the approach to add HCl to the standard precursors and by using the single molecule precursor methyltrichlorosilane (MTS). The efficiency of the process for different precursors, the growth rate stability and the effect that the C/Si and Cl/Si ratios have on the growth are studied. It is found that MTS is the most efficient precursor and that the growth becomes carbon limited at C/Si < 1. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Antimicrobial activity of chitosan attached to ethylene copolymer films
Authors: Joerger Rolf D. , Sabesan Subramaniam , Visioli Donna , Urian Dave , Joerger Melissa C.
Published: September 2008

Ethylene copolymer film was coated with chitosan by attachment of the polymer to the corona‐treated surface of the film, and the composite film was analysed for antimicrobial activity. The film was active against bacteria in 0.625 mM phosphate buffer; it reduced colony counts of Escherichia coli 25922 and of Listeria monocytogenes Scott A by 5 and 2–3 log10, respectively after 24 h exposure. The activity of the chitosan‐coated film against bacteria in buffer was increased when silver ions were incorporated into the films as demonstrated by complete killing of Escherichia coli O157:H7 DD3795 and the chicken exudate isolate Stenotrophomonas maltophilia within 2 h in buffer. The film was active against L. monocytogenes Scott A in 0.5% buffered peptone water up to a pH of about 7.0. Tests on beef and chicken meat exudates revealed antimicrobial activity of the film against Escherichia coli O157:H7 and L. monocytogenes Scott A of about 2 and 1–2 log10 reductions in colony‐forming units, respectively. The antimicrobial activity of the film against L. monocytogenes Scott A was also tested on turkey breast, and a log10 reduction of about 1.7 log10 units after 10 days and 1.2 log10 after 15 days at 4°C was achieved. Exposure to chitosan‐coated film and 350 MPa of pressure, 55°C or 1% sodium diacetate resulted in a synergistic effect. Copyright © 2008 John Wiley & Sons, Ltd
Correlation of Human and Animal Air‐to‐Blood Partition Coefficients With a Single Linear Free Energy Relationship Model
Authors: Sprunger Laura M. , Gibbs Jennifer , Acree William E. , Abraham Michael H.
Published: September 2008

Partition coefficients,Kblood, for gases and volatile organic compounds from air‐to‐blood have been collected from the published literature for human blood, rat blood, mouse blood, dog blood, rabbit blood, guinea pig blood, hamster blood, horse blood, pig blood, sheep blood, and cat blood. In total 358 partition coefficients were collected. The experimental log Kblooddata were correlated with expressions based on both the Abraham model and Goss modified Abraham model. Species indicator variables were added to the basic models to provide for interspecies variability in the observed log Kblooddata. The derived correlations describe the experimental log Kblooddata to within an approximate standard deviation of 0.31 log units. Training and test set analyses were used to validate the derived correlation models.
Global stability results for systems under sampled‐data control
Authors: Karafyllis Iasson , Kravaris Costas
Published: September 2008

In this work sufficient conditions for uniform input‐to‐output stability and uniform input‐to‐state stability are presented for finite‐dimensional systems under feedback control with zero‐order hold. The conditions are expressed by means of single and vector Lyapunov functions. Copyright © 2008 John Wiley & Sons, Ltd.
A control energy approach for the stabilization of the rigid beam balanced by the cart
Authors: Aguilar‐Ibañez Carlos F. , Guzmán‐Aguilar F. , Lozano Rogelio , Chimal E Juan C.
Published: September 2008

In this paper we present a control strategy for the stabilization of a rigid beam balanced by a cart. The control problem consists of horizontally balancing the beam by moving the cart backwards and forwards along the beam. The cart movement is restricted to always remain over the beam. The control strategy is based on the interconnection and damping assignment passivity based controller. The stability analysis is carried out using LaSalles's theorem. Copyright © 2008 John Wiley & Sons, Ltd.
A homotopy method for exact output tracking of some non‐minimum phase nonlinear control systems
Authors: Consolini L. , Tosques M.
Published: September 2008

This paper presents a method for non‐causal exact dynamic inversion for a class of non‐minimum phase nonlinear systems, which seems to be an alternative to those existing in the literature. This method is based on a homotopy procedure that allows to find a ‘small’ periodic solution of a desired equation by a continuous deformation of a known periodic solution of a simpler auxiliary system. This method allows to face the exact output tracking problem for some non‐minimum phase systems that are well known in the literature, such as the inverted pendulum, the motorcycle and the CTOL aircraft. Copyright © 2008 John Wiley & Sons, Ltd.
Confidence intervals for a ratio of two independent binomial proportions
Authors: Price Robert M. , Bonett Douglas G.
Published: September 2008

Several large‐sample confidence intervals for the ratio of independent binomial proportions are compared in terms of exact coverage probability and width. A non‐iterative approximate Bayesian interval is derived and its frequency properties are superior to all of the non‐iterative confidence intervals considered. The approximate Bayesian interval, which is very easy to compute, has performance characteristics that are very similar to the computationally intensive score method. Two sample size determination formulas are presented, one for desired absolute precision and the other for desired relative precision. Copyright © 2008 John Wiley & Sons, Ltd.
A class comparison method with filtering‐enhanced variable selection for high‐dimensional data sets
Authors: Lusa Lara , Korn Edward L. , McShane Lisa M.
Published: September 2008

High‐throughput molecular analysis technologies can produce thousands of measurements for each of the assayed samples. A common scientific question is to identify the variables whose distributions differ between some pre‐specified classes (i.e. are differentially expressed). The statistical cost of examining thousands of variables is related to the risk of identifying many variables that truly are not differentially expressed, and many different multiple testing strategies have been used for the analysis of high‐dimensional data sets to control the number of these false positives. An approach that is often used in practice to reduce the multiple comparisons problem is to lessen the number of comparisons being performed by filtering out variables that are considered non‐informative ‘before’ the analysis. However, deciding which and how many variables should be filtered out can be highly arbitrary, and different filtering strategies can result in different variables being identified as differentially expressed. We propose the filtering‐enhanced variable selection (FEVS) method, a new multiple testing strategy for identifying differentially expressed variables. This method identifies differentially expressed variables by combining the results obtained using a variety of filtering methods, instead of using a pre‐specified filtering method or trying to identify an optimal filtering of the variables prior to class comparison analysis. We prove that the FEVS method probabilistically controls the number of false discoveries, and we show with a set of simulations and an example from the literature that FEVS can be useful for gaining sensitivity for the detection of truly differentially expressed variables. Published in 2008 by John Wiley & Sons, Ltd.
The exact distribution of Cochran's heterogeneity statistic in one‐way random effects meta‐analysis
Authors: Biggerstaff Brad J. , Jackson Dan
Published: September 2008

The presence and impact of heterogeneity in the standard one‐way random effects model in meta‐analysis are often assessed using the Q statistic due to Cochran. We derive the exact distribution of this statistic under the assumptions of the random effects model, and also suggest two moment‐based approximations and a saddlepoint approximation for Q. The exact and approximate distributions are then applied to obtain the corresponding distributions of the recently proposed heterogeneity measures I2 and H, the power of the standard test for the presence of heterogeneity and confidence intervals for the between‐study variance parameter when the DerSimonian–Laird or the Hartung–Makambi estimator is used. The methodology is illustrated by revisiting a recent simulation study concerning the heterogeneity measures and applying all the proposed methods to four published meta‐analyses. Published in 2008 by John Wiley & Sons, Ltd.
Formulating tightest bounds on causal effects in studies with unmeasured confounders
Authors: Kuroki Manabu , Cai Zhihong
Published: September 2008

This paper considers the problem of evaluating the causal effect of an exposure on an outcome in observational studies with both measured and unmeasured confounders between the exposure and the outcome. Under such a situation, MacLehose et al. (Epidemiology 2005; 16:548–555) applied linear programming optimization software to find the minimum and maximum possible values of the causal effect for specific numerical data. In this paper, we apply the symbolic Balke–Pearl linear programming method (Probabilistic counterfactuals: semantics, computation, and applications. Ph.D. Thesis, UCLA Cognitive Systems Laboratory, 1995; J. Amer. Statist. Assoc. 1997; 92:1172–1176) to derive the simple closed‐form expressions for the lower and upper bounds on causal effects under various assumptions of monotonicity. These universal bounds enable epidemiologists and medical researchers to assess causal effects from observed data with minimum computational effort, and they further shed light on the accuracy of the assessment. Copyright © 2008 John Wiley & Sons, Ltd.
Pericallosal lipoma associated with Pai syndrome: prenatal imaging findings
Authors: Chousta A. , Ville D. , James I. , Foray P. , Bisch C. , Depardon P. , Rudigoz R.‐C. , Guibaud L.
Published: September 2008

Pai syndrome is a rare disorder characterized by the association of a midline pericallosal lipoma, median cleft (palate or lip) and cutaneous polyps of the face. Only seven cases have been reported in the medical literature and we are not aware of any previously reported prenatally detected cases. In this article, we present the prenatal ultrasound and magnetic resonance imaging findings of a syndromic pericallosal lipoma with associated anomalies that led to the prenatal diagnosis of Pai syndrome. We underline the impact on parental counseling following prenatal detection of pericallosal lipoma. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Characterization of basal seminal traits and reproductive endocrine profiles in North American river otters and Asian small‐clawed otters
Authors: Bateman Helen L. , Bond Jennifer B. , Campbell Mark , Barrie Michael , Riggs Gary , Snyder Barb , Swanson William F.
Published: September 2008

In this study, fecal samples were collected from 24 North American river (NARO) and 17 Asian small‐clawed otters (ASCO) for 6–36 months and semen collected seasonally from NARO males (n=4/season) via electroejaculation. Our main objectives were to: (1) characterize endocrine parameters by longitudinal monitoring of fecal hormone metabolites and (2) investigate semen collection and basal seminal traits in NARO. NARO demonstrated a distinct seasonality in the spring, with females having a monoestrual estrogen elevation lasting 15.33±1.98 (mean±SEM) days and males peaking in testosterone production for 25.50±7.51 days. Pregnancy was characterized by 7–9 months of basal fecal progesterone, presumably corresponding to embryonic diapause, followed by a rapid increase over the final 68–73 days to term. Pseudopregnancy exhibited a similar late winter progesterone peak of 68–72 days, which could not be differentiated from pregnancy. Geographic latitude possibly influenced the timing of increased testosterone in males and increased progesterone in pregnant/pseudopregnant females. In ASCO, monitoring of fecal estrogens did not allow consistent detection of peak values associated with behavioral estrus. Both pregnancy and pseudopregnancy were characterized by a moderate rise in fecal progesterone for 14–16 days postovulation followed by a marked increase. Total gestation length was 67–77 days compared with 62–84 days for pseudopregnancy. In NARO, optimal sperm recovery and quality occurred only in the spring, corresponding with seasonal increases in testicular volume and fecal testosterone. These findings represent the first comprehensive information on normative endocrine and seminal traits in freshwater otter species. Zoo Biol 28:107–126, 2009. © 2008 Wiley‐Liss, Inc.
Solution Strategies and Achievement in Dutch Complex Arithmetic: Latent Variable Modeling of Change
Authors: Hickendorff Marian , Heiser Willem J. , van Putten Cornelis M. , Verhelst Norman D.
Published: September 2008

In the Netherlands, national assessments at the end of primary school (Grade 6) show a decline of achievement on problems of complex or written arithmetic over the last two decades. The present study aims at contributing to an explanation of the large achievement decrease on complex division, by investigating the strategies students used in solving the division problems in the two most recent assessments carried out in 1997 and in 2004. The students’ strategies were classified into four categories. A data set resulted with two types of repeated observations within students: the nominal strategies and the dichotomous achievement scores (correct/incorrect) on the items administered.

It is argued that latent variable modeling methodology is appropriate to analyze these data. First, latent class analyses with year of assessment as a covariate were carried out on the multivariate nominal strategy variables. Results showed a shift from application of the traditional long division algorithm in 1997, to the less accurate strategy of stating an answer without writing down any notes or calculations in 2004, especially for boys. Second, explanatory IRT analyses showed that the three main strategies were significantly less accurate in 2004 than they were in 1997.
Long‐Chain Omega‐3 Polyunsaturated Fatty Acids in the Blood of Children and Adolescents with Juvenile Bipolar Disorder
Authors: Clayton Edward H. , Hanstock Tanya L. , Hirneth Stephen J. , Kable Colin J. , Garg Manohar L. , Hazell Philip L.
Published: September 2008

Reduced long‐chain omega‐3 polyunsaturated fatty acids (LCn‐3PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been reported in adult patients suffering from depression and bipolar disorder (BD). LCn‐3PUFA status has not previously been examined in children and adolescents with BD compared with healthy controls. Fifteen children and adolescents (9–18 years, M ± SD = 14.4 ± 3.48) diagnosed with juvenile bipolar disorder (JBD) and fifteen healthy age and sex‐matched controls were assessed for dietary intake and fasting red blood cell (RBC) membrane concentrations of LCn‐3PUFA. Fatty acid concentrations were compared between participants diagnosed with JBD and controls after controlling for dietary intake. RBC membrane concentrations of EPA and DHA were not significantly lower in participants diagnosed with JBD compared with healthy controls (M ± sem EPA = 3.37 ± 0.26 vs. 3.69 ± 0.27 µg/mL, P = 0.458; M ± sem DHA = 22.08 ± 2.23 vs. 24.61 ± 2.38 µg/mL, P = 0.528) after controlling for intake. Red blood cell DHA was negatively (r = −0.55; P = 0.044) related to clinician ratings of depression. Although lower RBC concentrations of LCn‐3PUFA were explained by lower intakes in the current study, previous evidence has linked reduced LCn‐3PUFA to the aetiology of BD. As RBC DHA was also negatively related to symptoms of depression, a randomised placebo‐controlled study examining supplementation with LCn‐3PUFA as an adjunct to standard pharmacotherapy appears warranted in this patient population.
Circulating Levels of Lectin‐Like Oxidized Low‐Density Lipoprotein Receptor‐1 are Associated with Inflammatory Markers
Authors: Lubrano Valter , Del Turco Serena , Nicolini Giuseppina , Di Cecco Pietro , Basta Giuseppina
Published: September 2008

Lectin‐like oxidized‐low‐density lipoprotein receptor‐1 (LOX‐1) is increasingly linked to atherosclerotic plaque formation and the soluble form of this receptor may reflect activities of disease. We investigated the associations among levels of sLOX‐1, oxidized‐low‐density lipoprotein (ox‐LDL), cytokines and the extension of atherosclerosis in patients with coronary artery disease (CAD). Lipid, TNF‐α, IL‐6, C reactive protein (CRP), ox‐LDL, peroxy radical and sLOX‐1 levels were measured in 29 controls and 60 patients with CAD, 30 of which with one or two vessels involved (group 1), and 30 patients with three or four vessels involved (group 2). The serum levels of sLOX‐1 were significantly and progressively higher in group 1 [611 (346–1,313) pg/ml, median (interquartile range)] and in group 2 [2,143 (824–3,201) pg/ml] than in control subjects [268 (111–767) pg/ml]. LOX‐1 levels positively correlated with IL‐6 (r = 0.38, P = 0.0042), TNF‐α (r = 0.38, P = 0.0037), CRP levels (r = 0.32, P = 0.027) and age (r = 0.25, P = 0.048). In the multivariate analysis TNF‐α resulted the only independent determinant of LOX‐1 serum levels (β‐value = 0.304, P = 0.017). These findings suggest that sLOX‐1 levels are up‐regulated during CAD progression and are associated with inflammatory markers. The measurement of the circulating soluble form of this receptor may be potentially useful in predicting CAD progression in humans.
Sesamin Supplementation Increases White Muscle Docosahexaenoic Acid (DHA) Levels in Rainbow Trout (Oncorhynchus mykiss) Fed High Alpha‐Linolenic Acid (ALA) Containing Vegetable Oil: Metabolic Actions
Authors: Trattner Sofia , Kamal‐Eldin A. , Brännäs E. , Moazzami A. , Zlabek V. , Larsson P. , Ruyter B. , Gjøen T. , Pickova J.
Published: September 2008

The effects of including an equi‐mixture of sesamin and episesamin in fish diets based on vegetable oils of different fatty acid composition were examined. Sesamin/episesamin (hereafter named sesamin) was included at 0.58 g/100 g diet. The oil used in the feed was either a mixture of linseed and sunflower oils (6:4, by vol) or 100% linseed oil. Addition of sesamin increased the percentages of docosahexaenoic acid (DHA) in white muscle phospholipid and triacylglycerol fraction by up to 37% but the fatty acids in red muscle and liver were not affected. The expression of the peroxisome proliferator‐activated receptor PPARα was significantly down regulated in the liver of the fish fed sesamin and mixed oil diet (P < 0.05). Sesamin and episesamin were detected in liver and muscle tissues of the fish that had been fed sesamin. Fish fed sesamin had elevated levels of total cytochrome P450 (CYP) enzymes and EROD activity in the liver, indicating an induction of CYP1A in this tissue. Our conclusion was that supplementation of fish feed with sesamin increased the proportions of DHA in the white muscle.
Substrate Preferences of a Lysophosphatidylcholine Acyltransferase Highlight Its Role in Phospholipid Remodeling
Authors: Kazachkov Michael , Chen Qilin , Wang Liping , Zou Jitao
Published: September 2008

An important enzyme involved in phospholipid turnover is the acyl‐CoA: lysophosphatidylcholine acyltransferase (LPCAT). Here, we report characterization of a newly discovered human LPCAT (LPCAT3), which has distinct substrate preferences strikingly consistent with a role in phosphatidylcholine (PtdCho) remodeling and modulating fatty acid composition of PtdCho. LPCAT3 prefers lysophosphatidylcholine (lysoPtdCho) with saturated fatty acid at the sn‐1 position and exhibits acyl donor preference towards linoleoyl‐CoA and arachidonoyl‐CoA. Furthermore, LPCAT3 is active in mediating 1‐O‐alkyl‐sn‐glycero‐3‐phosphocholine acylation with long chain fatty acyl‐CoAs to generate 1‐O‐alkyl‐phosphatidylcholine, another very important constitute of mammalian membrane systems. These properties are precisely the known attributes of LPCAT previously ascribed to the isoform involved in Lands' cycle, and thus strongly suggest that LPCAT3 is involved in phospholipids remodeling to achieve appropriate membrane lipid fatty acid composition.