bluuebunny/crossref_metadata_2025 huggingface dataset:
Forecasting oil price movements: Exploiting the information in the futures market
Authors: Coppola Andrea
Published: November 2007

Relying on the cost of carry model, the long‐run relationship between spot and futures prices is investigated and the information implied in these cointegrating relationships is used to forecast out of sample oil spot and futures price movements. To forecast oil price movements, a vector error correction model (VECM) is employed, where the deviations from the long‐run relationships between spot and futures prices constitute the equilibrium error. To evaluate forecasting performance, the random walk model (RWM) is used as a benchmark. It was found that (a) in‐sample, the information in the futures market can explain a sizable portion of oil price movements; and (b) out‐of‐sample, the VECM outperforms the RWM in forecasting price movements of 1‐month futures contracts. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:34–56, 2008
Determinants of Japanese Yen interest rate swap spreads: Evidence from a smooth transition vector autoregressive model
Authors: Huang Ying , Chen Carl R. , Camacho Maximo
Published: November 2007

This study investigates the determinants of variations in the yield spreads between Japanese yen interest rate swaps and Japan government bonds for a period from 1997 to 2005. A smooth transition vector autoregressive (STVAR) model and generalized impulse response functions are used to analyze the impact of various economic shocks on swap spreads. The volatility based on a GARCH (generalized autoregressive conditional heteroskedasticity) model of the government bond rate is identified as the transition variable that controls the smooth transition from a high volatility regime to a low volatility regime. The break point of the regime shift occurs around the end of the Japanese banking crisis. The impact of economic shocks on swap spreads varies across the maturity of swap spreads as well as regimes. Overall, swap spreads are more responsive to the economic shocks in the high volatility regime. Moreover, a volatility shock has profound effects on shorter maturity spreads, whereas the term structure shock plays an important role in impacting longer maturity spreads. Results of this study also show noticeable differences between the nonlinear and linear impulse response functions. © 2008 Wiley Periodicals, Inc. Jrl Fut Mark 28:82–107, 2008
Intracellular siRNA and precursor miRNA trafficking using bioresponsive copolypeptides
Authors: Rahbek Ulrik L. , Howard Kenneth A. , Oupicky David , Manickam Devika S. , Dong Mingdong , Nielsen Anne F. , Hansen Thomas B. , Besenbacher Flemming , Kjems Jørgen
Published: November 2007

Background

Small interfering RNAs (siRNAs) can induce specific gene silencing through cytoplasmic mRNA cleavage and nuclear transcriptional silencing, necessitating delivery to different cellular compartments. This study presents a reducible copolypeptide (rCPP) carrier containing different molar ratios of a histidine‐rich peptide (HRP) and nuclear localization sequence (NLS) peptide to modulate intracellular trafficking of transfected siRNA and primary RNA transcripts (pri‐miRNA).

Methods

Polyplex formation using siRNA and rCPP was demonstrated using photon correlation spectroscopy and atomic force microscopy. Confocal and fluorescence microscopy were used to investigate cellular uptake and nuclear trafficking whilst endogenous enhanced green fluorescent protein (EGFP) knockdown in H1299 cells was evaluated using flow cytometry. Transcriptional gene silencing of endogenous EF1A was verified using real‐time reverse‐transcription polymerase chain reaction (RT‐PCR) and pri‐miRNA nuclear processing was demonstrated using Northern analysis.

Results

rCPP‐based polyplexes showed rapid cellular uptake and low cytotoxicity. Labelled components revealed intact polyplexes after 2 h that exhibited directed movements consistent with endosomal trafficking. Polyplex‐mediated knockdown of EGFP increased with greater HRP content. The inclusion of NLS promoted nuclear localization of transfected siRNAs and pri‐miRNAs to the nuclear compartment allowing for transcriptional silencing of EF1A and Drosha and Dicer dependent expression of mature miRNA, respectively.

Conclusion

Our results demonstrate that reducible copolypeptides can be used as carriers for the non‐toxic cellular delivery of siRNA and pri‐miRNA. The nuclear targeting of rCPPs can be utilized for delivery of siRNAs and pri‐miRNAs to the nuclear compartment for transcriptional gene silencing or endogenous processing into mature miRNA, respectively, which could potentially lead to improved therapeutic approaches. Copyright © 2007 John Wiley & Sons, Ltd.
The role of other orientation in organizational citizenship behavior
Authors: Lester Scott W. , Meglino Bruce M. , Korsgaard M. Audrey
Published: November 2007

This article draws on social exchange theory and the theory of other orientation to examine how job satisfaction and individual differences are related to organizational citizenship behavior (OCB). Previous research specifying a direct effect for individual differences on OCB has yielded disappointing results. In contrast, this study examines the moderating role of individual differences in the relationship between job satisfaction and OCB. As hypothesized, results show a weaker relationship between job satisfaction and OCB for persons who are higher in other orientation. We discuss the theoretical implications of this finding and directions for future research. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of free amino acids in islets of Langerhans by high‐performance liquid chromatography using pre‐column derivatization with 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole
Authors: Yang Cailing , Jiang Xiaoman , Guo Linyuan , Zhang Haixia , Liu Mancang
Published: November 2007

A simple high‐performance liquid chromatographic method with pre‐column derivatization and fluorescence detection was developed and used for the analysis of free amino acids in islets of Langerhans; 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole (NBD‐Cl) served as pre‐column derivatization reagent. Islets of Langerhans were separated from the pancreas of normal and obese rats, treated with pre‐cooling methanol–water (80:20, v/v), and ultrasonicated to fragmentize the islets and effect deproteination. Several parameters influencing the derivatization reaction and chromatographic separation were optimized. Amino acid derivatives obtained under optimal conditions were separated on a C18 column with acetonitrile–acetate buffer as mobile phase and detected at 470 nm/540 nm (Ex/Em). Matrix effects were investigated and good linearities with correlation coefficients better than 0.9972 were obtained over a wide range of 0.42–42.11 μM for most of the amino acids. The detection limits (S/N = 3) were within the range of 6.1–51 nM. The precision of the method and recoveries were in the ranges of 1.43–10.76% (RSD%) and 85.07–108.82%, respectively. The analytical results showed that the serine content was markedly higher in normal rats than in obese rats, whereas methionine was of relatively lower content in both normal and obese rats.
Qualitative and quantitative study of nitrogen‐containing compounds in heavy gas oil using comprehensive two‐dimensional gas chromatography with nitrogen phosphorus detection
Authors: von Mühlen Carin , de Oliveira Eniz C. , Morrison Paul D. , Zini Claudia A. , Caramão Elina B. , Marriott Philip J.
Published: November 2007

In this work, a GC×GC–nitrogen–phosphorus detection (NPD) methodology was developed to separate and quantitate nitrogen‐containing compounds in Brazilian heavy gas oil. First, the NPD performance was improved in order to achieve best GC×GC performance. The geometry of this detector was also evaluated. The use of an extended jet improved significantly the peak shape. The GC×GC separation was studied using both first and second dimension columns with different internal diameters. The use of a thicker film in both dimensions provided better performance. LODs of 0.16–8.49 pg of individual compounds were achieved. Two different extraction techniques of the neutral and basic nitrogen‐containing compounds were also evaluated. The method using ion‐exchange resins to separate neutral and basic nitrogen‐containing compounds was more efficient than the method using modified silica. As an example, the amounts (μg/g) of each class reported were: indole (2.77), alkyl carbazoles ranging from C0 to C6+ (1.467), alkyl benzocarbazoles from C0 to C4+ (793), alkyl quinolines (31.2) and alkyl benzoquinolines (21.6) were quantitated.
Effect of organic modifier and temperature on the resolution of betamethasone and dexamethasone using a porous graphitic carbon column: Application to their identification and confirmation in human urine by LC‐ESI‐MS/MS
Authors: Oueslati Fethi , Hamida Najib Ben , Toumi Amor , Trabelsi Hassen
Published: November 2007

The effects of temperature, organic modifier and the type of acid on the retention factor, the resolution and peak shape of betamethasone and dexamethasone are described. The study is performed using narrow bore porous graphitic carbon (PGC) columns online with diode‐array detector (DAD) and ESI MS/MS. The results show that temperature affects the retention behaviour of the two compounds and ACN yields the best separation while no effect is obtained by changing the type of organic acid. The developed method is applied for the confirmation of dexamethasone and betamethasone in human urine.
HPLC method for preliminary analysis of constituents in rat blood after oral administration of the extract of Acanthopanax senticosus
Authors: Sun Hui , Lv Haitao , Zhang Yanmei , Meng Xiangcai , Sui Jinting , Wang Xijun , Bi Kaishun
Published: November 2007

An HPLC with SPE method has been developed for analysis of constituents in rat blood after oral administration of the extract of Acanthopanax senticosus (ASE). The plasma sample was prepared by SPE method equipped with Oasis HLB cartridge (3cc, 60 mg). The analysis was performed on a Dikma Diamonsil RP18 column (4.6 mm×150 mm, 5 μm) with the gradient elution of solvent A (ACN) and solvent B (0.1% aqueous phosphoric acid, v/v) and the detection wavelength was set at 270 nm. The calibration curve was linear over the range of 0.156–15.625 μg/mL. The LOD was 60 ng/mL. The intraday precision was less than 5.80%, and the interday precision was less than 6.0%. The recovery was (87.30 ± 1.73)%. As a result, 19 constituents were detected in rat plasma after oral administration of the ASE, including 11 original compounds in ASE and eight metabolites, and three of the metabolites originated from syringin in ASE. Six constituents were identified by comparing with the corresponding reference compounds.
Silicon as an emissive optical medium
Authors: Shainline J.M. , Xu J.
Published: November 2007

One of the great challenges in photonics has been to modify silicon to enhance light emission properties. In this review article we survey recent studies which have generated light from silicon in a variety of ways including introduction of emissive centers, anodization, fabrication of quantum‐confined structures and by utilizing non‐linear effects. Each method offers insight into silicon as an emissive medium, but no one method has proven effective enough a light source to compete with established technologies based on III‐V and II‐VI compound semiconductors, and in particular no one method of inducing light emission in silicon has made possible an electrically‐pumped silicon laser.
Biodegradable and Biomimetic Poly(ε‐caprolactone)/Poly(lactobionamidoethyl methacrylate) Biohybrids: Synthesis, Lactose‐Installed Nanoparticles and Recognition Properties
Authors: Zhou Wei , Dai Xiao‐Hui , Dong Chang‐Ming
Published: November 2007

Biodegradable and biomimetic SPCL‐PLAMA biohybrids were synthesized via ATRP and characterized by FT‐IR, 1H NMR, GPC and DSC. Biohybrids with small PDI were obtained, and the block length of the PLAMA glycopolymer could be varied linearly by the varying the molar ratio of glycomonomer to macroinitiator. The outer PLAMA glycopolymer restrained the crystallization of inner PCL segments. The self‐assembly properties of amphiphilic biohybrids were studied. Lactose‐installed aggregates were fabricated in aqueous solution; they changed from spherical micelles to vesicles with increasing weight fraction of hydrophobic PCL. The SPCL‐PLAMA biohybrids showed specific recognition for RCA120 lectin.

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Basic Law Controlling the Growth Regime of Layer‐by‐Layer Assembled Polyelectrolyte Multilayers
Authors: Jiang Xiuming , Chen Zhichun , Lv Deshui , Wu Qi , Lin Xianfu
Published: November 2007

A mathematical expression describing the growth regime of multilayers formed layer by layer and the correlation between the nature of the growth process and the distribution of the charges in the polyelectrolyte deposited on the surface of the film is reported. Two typical polyelectrolyte pairs were chosen such that one of them causes the film to grow linearly while the other causes the film to grow exponentially. The growth processes were monitored by UV‐Vis spectrophotometry and the experimental data was analyzed. The influence of the polyelectrolyte and NaCl concentration on the fabrication of PAH/PSS and PDDA/PSS films is discussed by analyzing the change of model parameters.

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Why is Stereoregular Polyacrylonitrile Obtained by Polymerization in Urea Canals Isotactic?
Authors: Yang Hyungchol , El‐Shafei Ahmed , Schilling Frederic C. , Tonelli Alan E.
Published: November 2007

Because stereoregular i‐PAN is obtained from the constrained polymerization of acrylonitrile monomer in expandable urea clathrates, we studied the inclusion compounds formed between guest AN and PANs and host cyclodextrins whose rigid channel diameters are in the range of the canals in urea clathrates. ICs of AN were successfully formed with α‐ and γ‐CDs but did not yield PANs, and only ICs between γ‐CD, and a‐ and i‐PANs were formed in solution. Modeling of AN and s‐ and i‐PAN‐CD‐ICs were performed using PM3 parameters to estimate their stabilities. We conclude that the polymerization of AN in urea clathrate channels produces predominantly i‐PAN as a consequence of its improved fit compared with s‐PAN.

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Free Radical Grafting of Polyethylene with Vinyl Monomers by Reactive Extrusion
Authors: Zhang Guofang , Jia Yuxi , Sun Sheng , Wu Lili , Zhao Guoqun , An Lijia
Published: November 2007

The free radical grafting of polyethylene with vinyl monomers by reactive extrusion was studied numerically. Numerical computation expressions of key variables, such as the concentrations of the initiator and polymer, grafting degree, average molecular weight and apparent viscosity, were deduced. The evolutions of the above variables were predicted by means of an uncoupled semi‐implicit iterative algorithm. The monomer conversion monotonically increases with decreasing throughput or increasing initial initiator concentration; with increasing barrel temperature, the monomer conversion first increases then decreases. The simulated results are nearly in good agreement with the experimental results.

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Impaired sexual behavior in male mice deficient for the β1–3 N‐Acetylglucosaminyltransferase‐I gene
Authors: Biellmann Franziska , Henion Timothy R. , Bürki Kurt , Hennet Thierry
Published: November 2007

The β1–3 N‐acetylglucosaminyltransferase‐1 (B3gnt1) gene encodes a poly‐N‐acetyllactosamine synthase which can initiate and extend poly‐N‐acetyllactosamine chains [Gal(β1–4)GlcNAc (β1–3)n]. Previous investigations with heterozygous and homozygous null mice for this gene have revealed the importance of poly‐N‐acetyllactosamine chains for the formation of olfactory axon connections with the olfactory bulb and the migration of gonadotropin releasing hormone neurons to the hypothalamus. The possible long‐term effects of these developmental defects, however, has not yet been studied. Here we have examined a reproductive phenotype observed in B3gnt1‐null mice. Whereas the B3gnt1 null females were fertile, the B3gnt1 null males were not able to sire litters at the expected rate when mated to either wildtype or B3gnt1‐null females. We assessed male sexual behavior as well as male reproduction parameters such as testes size, spermatogenesis, sperm number, morphology, and the development of early embryos in order to identify the source of a reduced rate of reproduction. Our findings show that the B3gnt1 null male reproductive organs were functional and could not account for the lower rate at which they produced offspring with wildtype conspecifics. Hence, we propose that the phenotype observed resulted from an impaired sexual response to female mating partners. Mol. Reprod. Dev. 75: 699–706, 2008. © 2007 Wiley‐Liss, Inc.
Models of sensor operations for border surveillance
Authors: Szechtman Roberto , Kress Moshe , Lin Kyle , Cfir Dolev
Published: November 2007

This article is motivated by the diverse array of border threats, ranging from terrorists to arms dealers and human traffickers. We consider a moving sensor that patrols a certain section of a border with the objective to detect infiltrators who attempt to penetrate that section. Infiltrators arrive according to a Poisson process along the border with a specified distribution of arrival location, and disappear a random amount of time after their arrival. The measures of effectiveness are the target (infiltrator) detection rate and the time elapsed from target arrival to target detection. We study two types of sensor trajectories that have constant endpoints, are periodic, and maintain constant speed: (1) a sensor that jumps instantaneously from the endpoint back to the starting‐point, and (2) a sensor that moves continuously back and forth. The controlled parameters (decision variables) are the starting and end points of the patrolled sector and the velocity of the sensor. General properties of these trajectories are investigated. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2008
HRK inactivation associated with promoter methylation and LOH in prostate cancer
Authors: Higuchi Tomonori , Nakamura Mitsutoshi , Shimada Keiji , Ishida Eiwa , Hirao Kazuya , Konishi Noboru
Published: November 2007

OBJECTIVES

Recent studies in selected human tumors have demonstrated reduced expression of HRK with hypermethylation. Because no similar study has been performed specifically in prostatic lesions, we examined whether the methylation status of HRK is altered in prostate cancers.

METHODS

We chose to analyze the hypermethylation status of HRK, the expression of HRK protein and mRNA with 12q13.1 loss of heterozygosity (LOH) and with p53 mutation, and lesion apoptotic indices as determined by transferase‐mediated digoxigenin‐tagged 16‐desoxy‐uridine‐triphosphate nick end‐labeling (TUNEL) assays in 53 prostate cancers.

RESULTS

Twenty of the 53 prostate cancers (38%) demonstrated hypermethylation in either the promoter or in exon 1 and, more significantly, the loss of HRK expression observed in 14 cancers by immunohistochemistry (IHC) was associated with promoter methylation. In addition, high apoptotic indices in tumors were related to positive HRK expression. Prostate cancers demonstrating HRK methylation also showed methylation of multiple other genes, such as p14ARF, p16INK4a, O6‐MGMT, and GTS‐P, but, with the exception of one case, p53 mutations were not detected. When compared to tumors having a Gleason score (GS) of 5–6, a significant difference in the apoptotic indices was found among prostate cancers of GS 7 (P < 0.001) or GS 8–9 (P = 0.007). We also detected a close correlation between the loss of HRK expression and decreased apoptosis in GS 5–6 and GS 7 tumors (P = 0.008, P < 0.001, respectively).

CONCLUSIONS

HRK appears to be inactivated principally by promoter hypermethylation in prostate cancers. We further suggest that the decreased expression of HRK may play an important role in tumor progression by modulating apoptotic cell death. Prostate 68: 105–113, 2008. © 2007 Wiley‐Liss, Inc.
Involvement of decreased Galectin‐3 expression in the pathogenesis and progression of prostate cancer
Authors: Merseburger Axel S. , Kramer Mario W. , Hennenlotter Jörg , Simon Perikles , Knapp Judith , Hartmann Jörg T. , Stenzl Arnulf , Serth Jürgen , Kuczyk Markus A.
Published: November 2007

BACKGROUND

Altered expression or loss of function of Galectin‐3 (Gal‐3) was suggested to be involved in the pathogenesis and progression of various human cancer entities. The aim of the present study is to determine the expression of Gal‐3 in prostate tissue emerging from a benign to a malignant, in the beginning hormone‐sensitive and finally hormone‐refractory status to further elucidate the role of this carbohydrate‐binding protein for the pathogenesis and/or progression of malignant prostatic disease.

MATERIALS AND METHODS

Five hundred and eighty three tissue samples from malignant, tumor adjacent benign, and histologically benign intra‐prostatic areas, retrieved out of 25 whole mounted prostate cancer (CaP) specimens and additional 95 samples of hormone‐refractory CaP, were processed to tissue microarrays. Immunohistochemical Gal‐3 expression was correlated with clinicopathological parameters among the different tissue entities.

RESULTS

Gal‐3 expression was significantly decreased in the hormone‐sensitive CaP specimens when compared with the respective benign tissue either localized far distant from the malignant lesion (P < 0.0001, Wilcoxon test) or directly neighboring the primary tumor (P < 0.0001). The staining reaction in the benign tissue areas directly neighboring the primary cancerous lesions differed significantly from the benign glands localized distant from the primary tumors (P < 0.001). A statistically highly significant, almost complete loss of Gal‐3 was observed in the hormone‐refractory when compared with the hormone‐sensitive tumors (P < 0.0001; mean staining score: 27.7% vs. 8.5%).

CONCLUSIONS

The present investigation clearly indicates decreased expression of Gal‐3 to be substantially involved in the pathogenesis and further progression of CaP from benign prostate glands to a finally hormone‐refractory malignant disease. Prostate 68: 72–77, 2008. © 2007 Wiley‐Liss, Inc.
Downregulation of androgen receptor expression by luteolin causes inhibition of cell proliferation and induction of apoptosis in human prostate cancer cells and xenografts
Authors: Chiu Feng‐Lan , Lin Jen‐Kun
Published: November 2007

BACKGROUND

Androgen receptor (ARs) play a crucial role in the development and progression of prostate cancer. Recent studies have suggested that prostate cancer cell proliferation is inhibited by AR downregulation. Our aim was to investigate how luteolin, a natural flavonoid, affects cell growth and AR expression in prostate cancer cells and xenografts.

METHODS

We assessed prostate cancer cell (LNCaP, DU145, and PC‐3) proliferation and apoptosis by MTT assay, flow cytometric analysis, and Western analysis. AR function was measured by evaluating the AR target molecule, prostate‐specific antigen (PSA), by RT‐PCR, Western blotting, and enzyme‐linked immunosorbent assay. We determined the mechanism of AR downregulation with cycloheximide chase assays, proteasome inhibitor, and coimmunoprecipitation experiments. The effects of luteolin on growth inhibition in vivo were examined by LNCaP xenografts in SCID mice.

RESULTS

Luteolin significantly repressed prostate cancer cell proliferation and induced apoptosis in LNCaP cells. PC‐3 and DU145 cells were less susceptible to luteolin‐mediated growth inhibition. Luteolin simultaneously suppressed intracellular and secreted PSA levels and repressed AR mRNA and protein expression in a dose‐ and time‐dependent manner. Luteolin reduced the association between AR and heat‐shock protein 90, causing AR degradation through a proteasome‐mediated pathway in a ligand‐independent manner. Luteolin also suppressed LNCaP xenograft tumor growth in SCID mice.

CONCLUSION

Luteolin‐mediated AR downregulation contributes to the inhibition of cell proliferation and the induction of apoptosis in LNCaP human prostate cancer cells, suggesting that AR is a molecular target for luteolin‐mediated anticancer activity. Luteolin may act as a chemopreventive or chemotherapeutic agent for prostate cancer. Prostate 68: 61–71, 2008. © 2007 Wiley‐Liss, Inc.
Reaction mechanism of HSH and CH3SH with NH2CH2COCH2X (X = F and Cl) molecules
Authors: Vijayakumar S. , Kolandaivel P.
Published: November 2007

The reaction mechanism of model compounds H2S and CH3SH for cysteine proteases with NH2CH2COCH2X (X = F and Cl) molecules has been investigated using DFT methods with B3LYP and B3PW91 hybrid density functionals at 6‐31+G* basis sets. The single point energy has been calculated for the above reactions with B3LYP and B3PW91 functionals using aug‐cc‐PVDZ infinite basis set in both gas and solution phases. The intrinsic reaction coordinates calculations have been performed to confirm that each transition state is linked by the desired reactants and products. The geometries and relative energies for various stationary points have been determined and discussed. The zero point vibrational energy corrections have been made to predict the reliable energy. The negative value of reaction energy indicates that the overall reaction profile is found to be exothermic. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Development and validation of an assay for the quantitative determination of cladribine nucleotides in MDCKII cells and culture medium using weak anion‐exchange liquid chromatography coupled with tandem mass spectrometry
Authors: Jansen Robert S. , Rosing Hilde , de Wolf Cocky J. F. , Beijnen Jos H.
Published: November 2007

The development and validation of an assay for the quantitative analysis of cladribine mono‐, di‐ and triphosphate (2‐chloro, 2′‐deoxyadenosine 5′‐mono‐, di‐ and triphosphate or 2CdAMP, 2CdADP and 2CdATP) in culture medium (Optimem) and cell lysate is described. Cladribine mono‐ and diphosphate reference compounds were obtained by thermal degradation of cladribine triphosphate. The reference compounds were characterized using ion‐pairing reversed‐phase high‐performance liquid chromatography with ultraviolet detection. The bioanalytical assay for 2CdAMP, 2CdADP and 2CdATP is based on weak anion‐exchange liquid chromatography coupled with tandem mass spectrometry in the positive ion mode (WAXLC/MS/MS). A fused‐silica electrospray capillary was used instead of a stainless steel electrospray capillary to minimize adsorption of analytes and thus decrease variation in the analyte signals. Dynamic ranges of 1.11–27.7, 0.550–55.0 and 1.31–52.3 nM for 2CdAMP, 2CdADP and 2CdATP, respectively, were validated in culture medium and cell lysate. Optimem samples required stabilization with 30% methanol to prevent conversion of 2CdATP into 2CdAMP and 2CdADP. All intra‐ and interday accuracies and precisions were within ±20%. The stability of the compounds was assessed under various analytically relevant conditions. The method was successfully used to investigate cladribine nucleotide transport in vitro in Madin‐Darby canine kidney II (MDCKII) cells. Copyright © 2007 John Wiley & Sons, Ltd.
A Chemically Amplified Fullerene‐Derivative Molecular Electron‐Beam Resist
Authors: Gibbons Francis , Zaid Hasnah M. , Manickam Mayandithevar , Preece Jon A. , Palmer Richard E. , Robinson Alex P. G.
Published: November 2007

Current lithographic resists depend on large polymeric materials, which are starting to limit further improvements in line‐width roughness and feature size. Fullerene molecular resists use much smaller molecules to avoid this problem. However, such resists have poor radiation sensitivity. Chemical amplification of a fullerene derivative using an epoxy crosslinker and a photoacid generator is demonstrated. The sensitivity of the material is increased by two orders of magnitude, and 20‐nm line widths are patterned.
Relevance of measuring diastolic time intervals in the ductus venosus during the early stages of twin–twin transfusion syndrome
Authors: Bensouda B. , Fouron J.‐C. , Raboisson M.‐J. , Lamoureux J. , Lachance C. , Leduc L.
Published: November 2007

Objective

To determine if the discrete myocardial diastolic dysfunction documented previously in the recipient twin during the early stages of twin–twin transfusion syndrome (TTTS) has any repercussion on flow velocities through the ductus venosus (DV) and to investigate if this could allow early differentiation between TTTS and selective intrauterine growth restriction (IUGR).

Methods

Two groups of monochorionic twin pregnancies with growth discordance between twins were reviewed retrospectively. Group I was composed of fetuses in Stages I and II of TTTS; laser or amnioreduction was not performed in any instance. Group II twin pairs each included one fetus with IUGR due to placental circulatory insufficiency. Intertwin differences (smaller minus larger fetus) were analyzed for myocardial performance index of the right ventricle (MPI‐RV) and for time variables in the DV.

Results

There were 38 pairs of monochorionic twins (24 TTTS and 14 IUGR) in this study. In the TTTS group, the donors had a significantly lower MPI‐RV (0.419 ± 0.18 vs. 0.596 ± 0.17, F(1, 19df) = 24.017, P < 0.001), a significantly longer total ventricular filling time (150.9 ± 25.6 ms vs. 124.0 ± 22.6 ms; F(1, 21df) = 19.631, P < 0.001) and a significantly longer early filling time (118.9 ± 22.9 ms vs. 92.6 ± 18.9 ms, F(1, 21df) = 28.419, P < 0.001) than had the recipient. None of these three differences was present in the IUGR group. Probability studies revealed that cut‐off values of 12.75 for intertwin differences in total filling time and 8.5 for intertwin differences in early filling time had sensitivities of 71% and 92%, respectively. The false‐positive rates were 23% and 15%, respectively, for the early diagnosis of TTTS.

Conclusion

In monochorionic twin pregnancies, shortening of the ventricular filling time in the recipient twin indicates diastolic myocardial dysfunction occurring early in the pathophysiology of TTTS. This early interwin difference in myocardial function is not found in pregnancies with IUGR in one twin due to placental circulatory insufficiency, allowing early differentiation between TTTS and selective IUGR. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Stage I twin–twin transfusion syndrome: rates of progression and regression in relation to outcome
Authors: O'Donoghue K. , Cartwright E. , Galea P. , Fisk N. M.
Published: November 2007

Objectives

Twin–twin transfusion syndrome (TTTS) results in high rates of perinatal mortality and neurological morbidity. Fetoscopic laser ablation of placental anastomoses is now established as the treatment of choice for advanced disease. However, there remains controversy about its use in early‐stage TTTS, in which laser‐related fetal losses need to be balanced against relatively favorable outcomes with more conservative approaches. We investigated rates of progression and regression in Stage I TTTS and determined factors influencing the course of the disease.

Methods

We undertook a retrospective observational study of all TTTS cases referred to our tertiary referral fetal medicine service from 2000 to 2006. In patients presenting with Stage I TTTS, the following variables were evaluated for their ability to predict the course and progression of the disease: gestational age (GA) at presentation, amniotic fluid index, recipient and donor deepest vertical pool, presence of artery–artery anastomoses, small‐sized bladder compared to normal donor bladder and fetal size discordance. Study end‐points were disease regression or progression, and neonatal survival at 28 days.

Results

Among 132 consecutive cases of TTTS, 46 women presented with Stage I disease. In the majority (69.6%), disease remained stable (28.3%) or regressed (41.3%). Of cases that progressed, 79% did so within 2 weeks and 93% progressed to at least Stage III. No factor was significantly linked with progression or regression, although there was a trend towards the absence of an artery–artery anastomosis (P = 0.10) and the presence of a small rather than normal donor bladder (P = 0.10) influencing progression, and later GA at presentation (P = 0.07) influencing regression. At least one infant survived in 83% of cases and there was double survival in 59%. Perinatal outcome was significantly better in cases that regressed (the rates of at least one survivor and double survival being 89% and 89%, respectively) or remained Stage I (77% and 61%, respectively), compared with those cases that progressed (79% and 14%, respectively). Treatment with amnioreduction at first presentation did not influence progression or regression.

Conclusions

This study demonstrates that a high percentage of Stage I TTTS cases regress or remain early stage. Identification of factors predicting progression would facilitate the selection of patients for definitive therapy, while avoiding treatment‐related morbidities in mild or transient disease. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Solar‐powered ZigBee‐based wireless motion surveillance: a prototype development and experimental results
Authors: Alexander Andell Anees , Taylor Raymond , Vairavanathan Vinujanan , Fu Yao , Hossain Ekram , Noghanian Sima
Published: November 2007

This paper describes the design and implementation of a solar‐powered wireless motion sensor surveillance network. Commercially available systems with similar functionality which exist today have several disadvantages including single points of failure and requires (semi) constant personnel attention as well as an elaborate power system. These systems require a lot of time to set up, they cannot be used in remote areas where a main power supply is unavailable, and are quite costly. Therefore, there is a need to develop a system which is portable, easy to set up, and is energy efficient. The wireless motion surveillance network described in this paper is designed to be portable, economically inexpensive, and energy efficient. The network is created using the IEEE 802.15.4 ZigBee wireless standard by implementing multiple Microchip PICDEM Z nodes. Each node in the network is equipped with a Direction Sensing Infrared Motion Detector (DSIMD) and a solar power unit (SPU). The DSIMD allows for detection of humans and animals alike moving into or out of the network. The system is powered by solar energy that makes it quite adaptable for remote applications. The network is able to cover an area of radius 30 m. By developing a low‐cost system, which is portable, easy to set up, and has an unlimited power supply, this technology is made accessible to a wider range of applications. The implementation of a CMOS camera is discussed at the end which can be used to take a snapshot of the detected object. Copyright © 2007 John Wiley & Sons, Ltd.
Terbutaline versus nifedipine for prolongation of pregnancy in patients with preterm labor
Authors: Mawaldi L. , Duminy P. , Tamim H.
Published: November 2007

Objective: To compare the effectiveness, safety, and possible adverse effects of terbutaline and nifedipine in prolonging pregnancy beyond 48 h. Methods: A randomized controlled trial was conducted with 174 pregnant women admitted with preterm labor randomized into 2 groups, which were given terbutaline (95 patients) and nifedepine (79 patients), respectively. Bivariate and multivariate analyses, using logistic regression, were used to analyze the data. Results: No statistically significant difference was found between the 2 groups in terms of prolongation of gestation to 48 h. The failure rate in terms of prolonging gestation for 24 h was found to be 12.6% for the terbutaline group and 10.1% for the nifedipine group, which was not found to be statistically significant (P value = 0.61). Side effects were significantly more common in the terbutaline group, except for maternal hypotension. Conclusion: Terbutaline and nifedipine appear to be equally effective in their tocolytic action. However, nifedipine did have the advantage of ease of administration. It also had significantly less effect on the fetal heart rate.
Lactation Resources for Clinicians
Authors: Turner‐Maffei Cynthia
Published: November 2007

Breastfeeding is widely acknowledged as the optimal infant feeding choice. However, many clinicians working in maternal and child health do not receive adequate university preparation to support breastfeeding. Knowledge and skill are most often gained through on‐the‐job and personal experience. Myriad resources exist to support clinicians in delivering the best quality care to breastfeeding clients. Among the available resources are policies and protocols of professional organizations, governmental, and health advocacy groups. Breastfeeding‐focused academic and continuing education programs are identified. Electronic and other resources for breastfeeding information are available for both professional and consumer audiences.
Lactation Complicated by Overweight and Obesity: Supporting the Mother and Newborn
Authors: Jevitt Cecilia , Hernandez Ivonne , Groër Maureen
Published: November 2007

Research shows that mothers who are obese (with a BMI >30) are less likely to initiate lactation, have delayed lactogenesis II, and are prone to early cessation of breastfeeding. Black women, with the highest rates of American obesity, have the lowest rates and shortest duration of breastfeeding compared to Hispanic and white women. Women who are overweight and obese have lowered prolactin responses to suckling. Women who are obese are at risk for prolonged labors, excessive labor stress, and cesarean birth, all of which delay lactogenesis II. Lactation has a small but significant role in preventing future obesity in the mother and child. Midwifery management of obesity‐related lactation problems begins with education about optimal prenatal weight gain and regular weight assessment to avoid excessive gain. Support of physiologic birth processes to avoid stress, prolonged labor, and surgical birth and limit maternal‐newborn separation enhances the onset of lactogenesis II. Massage or pumping may soften and extend the obese nipple for easier latch. Infants of lactating women with prior bariatric surgery are at risk for B12 deficiency and require regular nutrition and growth assessment. Five hundred calorie per day restriction paired with aerobic exercise for intentional postpartum weight loss does not affect milk quality or infant growth.
Recognizing and Treating Delayed or Failed Lactogenesis II
Authors: Hurst Nancy M.
Published: November 2007

Delayed or failed achievement of lactogenesis II—the onset of copious milk volume—occurs as a result of various maternal and/or infant factors. Early recognition of these risk factors is critical for clinicians who interact with breastfeeding women so that intervention and achievement of full or partial breastfeeding can be preserved. This article describes the maternal and infant conditions that contribute to the unsuccessful establishment of a full lactation. Treatment modalities that can maximize maternal lactation capacity and infant growth rates are offered.
Breastfeeding Peer Counselors in the United States: Helping to Build a Culture and Tradition of Breastfeeding
Authors: Rossman Beverly
Published: November 2007

Traditionally, women have relied upon the wisdom and experience of other women to learn about mothering and breastfeeding. In the United States, however, this once‐standard mother‐to‐mother interaction was almost nonexistent by the mid–20th century. Recent advances in the understanding of the benefits of breastfeeding for maternal and child health have led most professional organizations to advocate breastfeeding as the norm of infant feeding. Promotional breastfeeding efforts over the past 3 decades include strategies to strengthen support for breastfeeding in the health care system and in the community. Breastfeeding peer counseling represents a model of mother‐to‐mother support which emerged in the 1980s as a community‐based resource to provide mothers with the support and assistance needed to establish and maintain breastfeeding in the early weeks and months postpartum. This article describes the role, training, and effectiveness of breastfeeding peer counselors and discusses ways that mothers and peer counselors might benefit from the connection and relationship that develops between the breastfeeding mother and her peer counselor. An exemplar of a breastfeeding peer counseling program is presented.
An Update on the Recognition and Management of Lactational Breast Inflammation
Authors: Betzold Christine M.
Published: November 2007

Inflammation of the breast (mastitis) with or without infection or redness has a variety of etiologies and presentations that range from the fairly benign blocked duct to the more serious breast abscess. True infectious mastitis can present in a manner that is easily identifiable, or it can present in a subtle and ambiguous fashion. Some women are challenged with recurrent mastitis, and often the underlying etiology is never discovered. This review will assist the clinician in recognizing, efficiently diagnosing, and effectively treating breast inflammation caused by infectious and noninfectious processes, including recurrent mastitis. Tables and a flowchart that outline breast inflammation and recurrent mastitis are provided.
Increased Lactation Risk for Late Preterm Infants and Mothers: Evidence and Management Strategies to Protect Breastfeeding
Authors: Meier Paula P. , Furman Lydia M. , Degenhardt Marguerite
Published: November 2007

Late preterm infants (34 0/7–36 6/7 weeks of gestation) are often cared for in general maternity units by clinicians who have limited experience with the specific needs of these newborns. Although the benefits of human milk are well documented, mothers and their late preterm infants are at risk for poor lactation outcomes. These include early breastfeeding cessation and lactation‐associated morbidities, including poor growth, jaundice, and dehydration. Late preterm infants are more likely than term infants to develop temperature instability, hypoglycemia, respiratory distress, jaundice, feeding problems, and to require rehospitalization in the first 2 weeks postbirth. Breastfeeding can exacerbate these problems, because late preterm infants often lack the ability to consume an adequate volume of milk at breast, and their mothers are at risk for delayed lactogenesis. This article reviews strategies to protect breastfeeding for the late preterm infant and mother dyad by establishing and maintaining maternal milk volume while facilitating adequate infant intake.
Latching‐On and Suckling of the Healthy Term Neonate: Breastfeeding Assessment
Authors: Cadwell Karin
Published: November 2007

Increasing breastfeeding duration and exclusivity is an acknowledged public health priority. Breastfeeding problems, especially with the healthy term neonate latching‐on or feeding with a suboptimal latch, are common reasons for early breastfeeding termination when they result in inadequate breastfeeding, poor milk transfer, and sore nipples. This article describes clinical strategies for systematic latch‐on and suckling assessment with the goal of improving the skills of clinicians who provide care for breastfeeding women.
A Reassessment of the Metastable Miscibility Gap in Al-Ag Alloys by Atom Probe Tomography
Authors: Marquis Emmanuelle A.
Published: November 2007

The evolution of Guinier-Preston zones in an Al-2.7 at.% Ag alloy was studied using atom probe tomography. The composition and morphology of the GP zones are time dependent, explaining discrepancies in previous work. This result requires the metastable miscibility gap for GP zones to be reevaluated, highlighting the importance of the temporal evolution of the GP zones. Preliminary results on the composition of γ′ and γ plates are also presented.
Atom Probe Tomographic Studies of Precipitation in Al-0.1Zr-0.1Ti (at.%) Alloys
Authors: Knipling Keith E. , Dunand David C. , Seidman David N.
Published: November 2007

Atom probe tomography was utilized to measure directly the chemical compositions of Al3(Zr1−xTix) precipitates with a metastable L12structure formed in Al-0.1Zr-0.1Ti (at.%) alloys upon aging at 375°C or 425°C. The alloys exhibit an inhomogeneous distribution of Al3(Zr1−xTix) precipitates, as a result of a nonuniform dendritic distribution of solute atoms after casting. At these aging temperatures, the Zr:Ti atomic ratio in the precipitates is about 10 and 5, respectively, indicating that Ti remains mainly in solid solution rather than partitioning to the Al3(Zr1−xTix) precipitates. This is interpreted as being due to the very small diffusivity of Ti in α-Al, consistent with prior studies on Al-Sc-Ti and Al-Sc-Zr alloys, where the slower diffusing Zr and Ti atoms make up a small fraction of the Al3(Sc1−xTix/Zrx) precipitates. Unlike those alloys, however, the present Al-Zr-Ti alloys exhibit no interfacial segregation of Ti at the matrix/precipitate heterophase interface, a result that may be affected by a significant disparity in the evaporation fields of the α-Al matrix and Al3(Zr1−xTix) precipitates and/or a lack of local thermodynamic equilibrium at the interface.
New Techniques for the Analysis of Fine-Scaled Clustering Phenomena within Atom Probe Tomography (APT) Data
Authors: Stephenson Leigh T. , Moody Michael P. , Liddicoat Peter V. , Ringer Simon P.
Published: November 2007

Nanoscale atomic clusters in atom probe tomographic data are not universally defined but instead are characterized by the clustering algorithm used and the parameter values controlling the algorithmic process. A new core-linkage clustering algorithm is developed, combining fundamental elements of the conventional maximum separation method with density-based analyses. A key improvement to the algorithm is the independence of algorithmic parameters inherently unified in previous techniques, enabling a more accurate analysis to be applied across a wider range of material systems. Further, an objective procedure for the selection of parameters based on approximating the data with a model of complete spatial randomness is developed and applied. The use of higher nearest neighbor distributions is highlighted to give insight into the nature of the clustering phenomena present in a system and to generalize the clustering algorithms used to analyze it. Maximum separation, density-based scanning, and the core linkage algorithm, developed within this study, were separately applied to the investigation of fine solute clustering of solute atoms in an Al-1.9Zn-1.7Mg (at.%) at two distinct states of early phase decomposition and the results of these analyses were evaluated.
Sind psychologische Prozesse kointegriert?
Authors: Stroe-Kunold Esther , Werner Joachim
Published: November 2007

Zusammenfassung. Die psychologische Prozessperspektive hat eine Erweiterung des erforschbaren Spektrums menschlicher Phänomene mit sich gebracht. Das hier vorgestellte Verfahren trägt zu dieser Entwicklung bei, indem es die Dynamik psychologischer Prozesse erfassbar macht. Mithilfe der Kointegrationsmethodologie ist die Modellierung und Analyse der (Wechsel-)Beziehungen zwischen mehreren zeitlich instabilen Prozessen möglich. In der ökonometrischen Forschung gehören kointegrationsmethodologische Verfahren seit Jahren zum methodologischen Standardrepertoire. Diese Überblicksdarstellung versucht zu klären, inwiefern das Kointegrationskonzept als zeitreihenanalytisches Auswertungsverfahren für die psychologische Prozessforschung ein hohes Anwendungspotential und unmittelbare Relevanz besitzt. Der Beitrag wird durch einen Exkurs über die Grundbegriffe der Zeitreihenanalyse eingeleitet. Darauf aufbauend wird in die Grundidee des Kointegrationskonzepts eingeführt, um anschließend die gegenwärtige Rolle in der psychologischen Prozessforschung und Perspektiven als psychologisches Auswertungsinstrument anhand möglicher Anwendungsfelder aufzuzeigen.