bluuebunny/crossref_metadata_2025 huggingface dataset:
Cost‐effective public health guidance: asking questions from the decision‐maker's viewpoint
Authors: Chalkidou Kalipso , Culyer Anthony , Naidoo Bhash , Littlejohns Peter
Published: September 2007

In February 2004, in his assessment of the long‐term financial viability of the NHS, Derek Wanless recommended the use of ‘a consistent framework, such as the methodology developed by NICE, to evaluate the cost‐effectiveness of interventions and initiatives across health care and public health’. One year later public health was added to NICE's remit and the new National Institute for Health and Clinical Excellence (NICE) was established, with amended statutory instruments to permit consideration of broader public sector costs when developing cost‐effective guidance for public health.

With the principle of ‘a consistent framework’ put forward by Wanless as the starting point, this paper provides an insight into the most challenging aspects of applying the principles of cost‐effectiveness analysis in the public health context from the policymaker's perspective. It reflects on the long‐term consequences of taking on responsibility for producing public health guidance on the Institute's overall approach to guidance development and describes the tension between striving for consistency and cross‐evaluation comparability while ensuring that the methodological tools used are fit for the purpose of developing public health guidance. Copyright © 2007 John Wiley & Sons, Ltd.
HPV triage testing or repeat Pap smear for the management of atypical squamous cells (ASCUS) on Pap smear: is there evidence of process utility?
Authors: Howard Kirsten , Salkeld Glenn , McCaffery Kirsten , Irwig Les
Published: September 2007

A two‐stage standard gamble was used to evaluate women's preferences for alternative managements of atypical squamous cells of undermined significance (ASCUS) on Pap smear (repeat Pap smear compared with immediate HPV test), and to test for the evidence of process utility.

Women's utilities for the health state scenarios were clustered towards the upper end of the 0–1 scale with considerable variability in women's preferences. There was evidence of process utility, with immediate human papillomavirus (HPV) testing strategies having lower valuations than repeat Pap smear, where the clinical outcome was the same. Mean (95% CI) utilities for HPV testing (negative test) followed by resolution were 0.9967 (0.9957–0.9978) compared with repeat Pap smear followed by resolution: 0.9972 (0.9964–0.9980). Mean (95% CI) utilities for immediate HPV testing (positive test), followed by colposcopy, biopsy and treatment were 0.9354 (0.8544–1.0) compared with repeat Pap smear followed by colposcopy, biopsy and treatment: 0.9656 (0.9081–1.0).

Our results add to the existing evidence that the impact of healthcare interventions on well‐being is not limited to the effect of the intervention on the health outcomes expected from the intervention; process of care can have quality of life implications for the individual. A modelled application of trial‐based data will allow characterisation of the true population costs, benefits, risks and harms of alternative triage strategies and subsequent policy implications thereof. Copyright © 2007 John Wiley & Sons, Ltd.
Cost‐effectiveness analysis of a multinational RCT with a binary measure of effectiveness and an interacting covariate
Authors: Willan Andrew R. , Kowgier Matthew E.
Published: September 2007

In a recent multinational randomized clinical trial, 1356 patients from 14 countries were randomized between two arms. The primary measure of effectiveness was 30‐day survival. Health care utilization was collected on all patients and was combined with a single country's price weights to provide patient‐level cost data. The purpose of this paper is to report the results of the cost‐effectiveness analysis for the country that provided the cost weights, so as to provide a case study for illustrating recently proposed methodologies that account for skewed cost data, the between‐country variation in treatment effects, possible interactions between treatment and baseline covariates, and the difficulty of estimated adjusted risk differences. A hierarchal model is used to account for the two sources of variation (between country and between patients, within a country). The model, which uses gamma distributions for cost data and recent methods for estimating adjusted risk differences, provides overall and country‐specific estimates of treatment effects. Model estimation is facilitated by Markov chain Monte Carlo methods using the WinBUGS software. In addition, the theory of expected value of information is used to determine if the data provided by the trial are sufficient for decision making. Copyright © 2007 John Wiley & Sons, Ltd.
Water and globalization: case study of Central Asia
Authors: Dukhovny V. A.
Published: September 2007

The present‐day world is enmeshed in global networks. The information space has been formed according to rules of Internet and electronic messaging and ensures instantaneous communication and momentary dissemination of any news, thus bringing about apparent unity of the world. Other networks (financial, trade, economic, legal and institutional) have their own rules, while being in motion and interacting with each other they represent a phenomenon of globalization.

In the water sector, with its several aspects, this process has influenced politics, economy, technology, environment, culture, ideology and even religion since the 1950s. Each globalization aspect produced its effect on the water sector in countries, regions, and the world, even in periods and countries where the sector was developed independently.

These aspects play different roles at each development stage. The degrees to which globalization penetrates at regional and national levels are different, dependent on the degree of the anti‐effect of governance. Dynamics of the processes are quite representative in Central Asia, which despite being behind the Iron Curtain for a long time could not withstand global trends and tendencies. The influence of “globalism” on the water sector in Central Asia is presented in this paper. Copyright © 2007 John Wiley & Sons, Ltd.
Novel sodium alginate/polyethyleneimine polyion complex membranes for pervaporation dehydration at the azeotropic composition of various alcohols
Authors: Devi D Anjali , Smitha Biduru , Sridhar Sundergopal , Jawalkar Sheetal S , Aminabhavi Tejraj M
Published: September 2007

Dense polyion complex membranes of anionic sodium alginate (NaAlg) and cationic polyethyleneimine (PEI) were prepareand crosslinked with glutaraldehyde for dehydration of alcohol–water mixtures by pervaporation (PV). The membranes were characterized by ion‐exchange capacity measurement, Fourier transform infrared spectroscopy, differential scanning calorimetry and scanning electron microscopy to investigate the extent of cross‐linking, intermolecular interactions, thermal stability, and surface and cross‐sectional morphologies, respectively. Wide‐angle X‐ray diffraction was used to investigate the crystallinity of the membranes. PV dehydration characteristics of the membranes were determined as a function of PEI content, crosslinking time as well as feed water composition. Transport parameters such as sorption, diffusion and permeability of water and alcohols through the membranes were determined. Among the four different membrane compositions, the polyion complex containing 40% PEI was found to yield optimum separation data in terms of membrane stability, selectivity and permeability. On the other hand, 10% PEI‐containing membrane gave the highest selectivity with the lowest flux at ambient temperature, but the membranes were not sufficiently stable. Copyright © 2007 Society of Chemical Industry
Evaluation of biosorbents for Cu removal from wastewater in the presence of EDTA
Authors: Gabaldón Carmen , Izquierdo Marta , Marzal Paula , Sempere Feliu
Published: September 2007

BACKGROUND: This paper evaluates the use of several biosorbents for Cu removal from aqueous solutions in the absence and presence of ethylenediaminetetraacetic acid (EDTA). The objective was to determine the applicability of the sorption process after conventional physicochemical wastewater treatment, or as primary treatment, replacing the physicochemical process.

RESULTS: Fixed‐bed experiments were performed at Cu influent concentrations of 2 and 20 mg dm−3 and EDTA doses between 0 and 10 mg dm−3. At low Cu concentration without EDTA, Cu uptake capacity followed the order Posidonia oceanica > chitosan > chitin > Scharlau AC > Darco AC, with a maximum, at C/C0 = 0.2, of 23.2 mg g−1. In the presence of EDTA, Cu was detected in the effluent from the beginning of the operation, except for the activated carbons and chitosan at low EDTA doses. At higher EDTA doses, the activated carbons showed the best performance. Uptakes at Cu concentration of 20 mg dm−3 without EDTA were 51.6 (Posidonia oceanica) and 41.4 mg g−1 (chitosan) at C/C0 = 0.2.

CONCLUSION: A sequence of one fixed bed with Posidonia oceanica followed by another with Scharlau AC should be an alternative to Cu precipitation, with Cu effluent concentration lower than 0.5 mg dm−3 for more than 350 pore volumes. Copyright © 2007 Society of Chemical Industry
Enzymatic hydrolysis and fermentation of lime pretreated wheat straw to ethanol
Authors: Saha Badal C , Cotta Michael A
Published: September 2007

BACKGROUND: The objective of this work is to develop an efficient pretreatment method that can help enzymes break down the complex carbohydrates present in wheat straw to sugars, and to then ferment of all these sugars to ethanol.

RESULTS: The yield of sugars from wheat straw (8.6%, w/v) by lime pretreatment (100 mg g−1 straw, 121 °C, 1 h) and enzymatic hydrolysis (45 °C, pH 5.0, 120 h) using a cocktail of three commercial enzyme preparations (cellulase, β‐glucosidase, and xylanase) at the dose level of 0.15 mL of each enzyme preparation g−1 straw was 568 ± 13 mg g−1 (82% yield). The concentration of ethanol from lime pretreated enzyme saccharified wheat straw (78 g) hydrolyzate by recombinant Escherichia coli strain FBR5 at pH 6.5 and 35 °C in 24 h was 22.5 ± 0.6 g L−1 with a yield of 0.50 g g−1 available sugars (0.29 g g−1 straw). The ethanol concentration was 20.6 ± 0.4 g L−1 with a yield of 0.26 g g−1 straw in the case of simultaneous saccharification and fermentation by the E. coli strain at pH 6.0 and 35 °C in 72 h.

CONCLUSION: The results are important in choosing a suitable pretreatment option for developing bioprocess technologies for conversion of wheat straw to fuel ethanol. Copyright © 2007 Society of Chemical Industry
Interfacing biocatalysis and organic synthesis
Authors: Wohlgemuth Roland
Published: September 2007

The path to new chemical entities often shows the limitations of existing tools both in biocatalysis and organic chemistry. Organic synthetic procedures to prepare a compound in a target‐oriented synthesis can damage other functional parts of the molecule. Protection–deprotection schemes can lead to a dead end, when a certain protecting group cannot be cleaved off. In biocatalysis, on the other hand, the required biocatalytic toolbox and methodology might not be readily available, therefore limiting a biocatalytic approach. New toolboxes, ingredients, and methodologies at the interface of classical organic synthesis and biocatalytic reactions bridge the gap between these two areas. Since product isolation and purification involves a substantial amount of time in the preparation of chemicals, methodologies to simplify these tasks are necessary to get the pure product into the bottle with less work‐up time.

Efficient and safe new pharmaceuticals, intermediates and analytical reagents need to be prepared under certain safety, health, environmental and economical boundary conditions. Biocatalytic reactions have been shown to overcome these limitations successfully and are becoming increasingly important in industrial manufacturing.

Building bridges between biocatalysis and organic synthesis will therefore create roads to new synthetic strategies and technological frontiers of both fundamental and practical interest. Copyright © 2007 Society of Chemical Industry
Organic acid enhanced electrodialytic extraction of lead from contaminated soil fines in suspension
Authors: Jensen Pernille E , Ahring Birgitte K , Ottosen Lisbeth M
Published: September 2007

The implementation of soil washing technology for the treatment of heavy metal contaminated soils is limited by the toxicity and unwieldiness of the remaining heavy metal contaminated sludge. In this work, the feasibility of combining electrodialytic remediation with heterotrophic leaching for decontamination of the sludge was investigated. The ability of 11 organic acids to extract Pb from the fine fraction of contaminated soil (grains < 63 µm) was investigated, and application of the acids as enhancing reagents during electrodialytic remediation (EDR) of Pb‐contaminated soil fines in suspension was tested. Five of the acids showed the ability to extract Pb from the soil fines in excess of the effect caused solely by pH changes. Addition of the acids, however, severely impeded EDR, hence promotion of EDR by combination with heterotrophic leaching was rejected. In contrast, enhancement of EDR with nitric acid gave promising results. Copyright © 2007 Society of Chemical Industry
Integration of biocatalytic conversions into chemical syntheses
Authors: Hailes Helen C , Dalby Paul A , Woodley John M
Published: September 2007

The future application of enzymes in organic synthesis is in part dependent on excellent integration with the neighbouring chemical conversions. This paper outlines some of the key issues to be addressed to achieve optimal integration either by modification of preceding (or following) chemical steps, biocatalyst evolution or combinations of these approaches together with process engineering. Copyright © 2007 Society of Chemical Industry
Economized large‐scale production of high yield of rAAV for gene therapy applications exploiting baculovirus expression system
Authors: Negrete Alejandro , Yang Linda C. , Mendez Andres F. , Levy Justin R. , Kotin Robert M.
Published: September 2007

Background

The versatility of recombinant adeno‐associated vector (rAAV) as a gene delivery system is due to the vector's ability to transduce different cell types as well as dividing and non‐dividing cells. Large‐scale production of rAAV remains one of the major challenges for continued development of pre‐clinical and clinical studies, and for its potential commercialization. The baculovirus expression vectors (BEVS) and insect cells represent a potential method to produce rAAV economically at large scale. This technology uses three different BEVs (Bac‐Rep, Bac‐GFP, and Bac‐VP) each at a multiplicity of infection (MOI) of 3. We reported previously the production of rAAV at 40 L scale using a stirred‐tank bioreactor (STB). However, production in larger volumes is limited by the stability of the BEVs and amount of BEVs needed to achieve the target MOI of 3 per BEV. Here, the production parameters were optimized and the baculovirus stability was determined.

Methods

The stability of the three types of baculovirus used to produce rAAV was determined for six expansion passages by protein expression analysis. To economize baculovirus, MOI and cell density at time of infection (TOI) were evaluated initially at small scale and then applied to the 10 L scale.

Results

An MOI = 0.03 and TOI cell density of 1 × 106 cells/mL produced high titer rAAV without comprising yield. To confirm the scalability of the process, rAAV was produced in a 10 L STB using the optimized parameters obtaining a 10× increase in yield (∼1 × 1014 rAAV DNAse‐resistant particles per liter).

Conclusion

These findings contribute to the process development for large‐scale production of rAAV for gene therapy applications and its commercialization. Copyright © 2007 John Wiley & Sons, Ltd.
Measurement and calculation of the Q‐branch spectrum of nitrogen using inverse Raman spectroscopy and cw Raman‐induced polarization spectroscopy
Authors: Naik Sameer V. , Hwang Jungyu , Lucht Robert P. , Laurendeau Normand M.
Published: September 2007

The techniques of inverse Raman spectroscopy, Raman‐induced polarization spectroscopy (RIPS), and optical heterodyne RIPS (OHD‐RIPS) are compared by probing the Q‐branch of the nitrogen molecule. The signal is measured employing either a photomultiplier tube (low background level–RIPS) or a photodetector (high background level–IRS and OHD‐RIPS). The measurements are performed using atmospheric mixtures of N2Ar with concentrations varying from 0 to 79% N2. This strategy permits estimation of detection limits using the different techniques. Pump and probe energy levels are varied independently to study signal dependence on laser irradiance. A theoretical treatment is presented on the basis of the Raman susceptibility equations, which permits the calculation of spectra for all three techniques. Calculated Q‐branch spectra are compared with the measured spectra for the interactions of a linearly polarized probe beam with a linearly or circularly polarized pump beam. The polarizer angle in the detection path for OHD‐RIPS has a dramatic effect on the shape of the spectrum. The calculated and experimental OHD‐RIPS spectra are in good agreement over the entire range of investigated polarizer angles. Detection limits using these techniques are analyzed to suggest their applicability for measuring other species of importance in combustion and plasma systems. Copyright © 2007 John Wiley & Sons, Ltd.
One‐Pot Approach to Synthesize Star‐Shaped Polystyrenes via RAFT‐Mediated Radical Copolymerization
Authors: Liu Qingchun , Chen Yongming
Published: September 2007

Previously, we have reported a one‐pot approach to generate star‐shaped polymers by copolymerization of a maleimide inimer or bismaleimide hexane (BMIH) and a large excess of styrene (St) via atom transfer radical polymerization. Herein, we extended this approach towards the synthesis of star polystyrene through reversible addition fragmentation chain‐transfer (RAFT)‐mediated radical copolymerization of BMIH and an excess of St with cumyl dithiobenzoate (CDB) as a chain‐transfer agent (CTA). It was illustrated that the PS arms were grafted from the preformed core, which was formed in situ during the copolymerization of BMIH and St. Therefore, this facile one‐pot approach can be performed by applying different type of controlled radical polymerization. However, linear PS still was generated as a byproduct which had been observed previously.

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Influence of Short‐Chain Branching of Polyethylenes on the Temperature Dependence of Rheological Properties in Shear
Authors: Stadler Florian J. , Gabriel Claus , Münstedt Helmut
Published: September 2007

This contribution describes the influence of short‐chain branching on the temperature dependence of rheological properties of polyethylene (PE) melts in shear. The materials investigated are linear and short‐chain branched, metallocene‐catalyzed PEs of narrow molecular mass distribution. The linear viscoelastic properties are determined by dynamic‐mechanical analysis. Short‐chain branching (SCB) leads to an increase of the flow activation energy. The activation energy was found to increase linearly with rising weight comonomer content.

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Influence of Chain Structure on Phase Behavior and Thermal Degradation of Poly(trimethylene terephthalate)/Poly(hydroxy ether) of Bisphenol‐A Blends
Authors: Farmahini‐Farahani Madjid , Jafari Seyed Hassan , Khonakdar Hossein Ali , Yavari Ahmad , Bakhshi Raheleh , Tarameshlou Mohammad
Published: September 2007

This paper describes thermal decomposition and phase behavior of binary blends composed of poly(trimethylene terephthalate), (PTT), and a phenoxy resin namely poly(hydroxy ether) of bisphenol‐A prepared via melt blending. Analysis of the SEM and DMA results revealed that except for PTT/phenoxy 90/10 sample, all PTT/phenoxy blends were homogeneous. The reactions occurring in PTT/phenoxy system and their effect on molecular weight were investigated by 1H NMR and GPC respectively. 1H NMR spectra proved that the reaction of grafting PTT on phenoxy chains occurs in the system which eventually leads to formation of cross‐linked structures in the system. It was also found that chain scission reactions are responsible for decreasing molecular weight at low temperatures, while at higher temperatures formation of cross‐linked structures increases thermal stability of the blends. Investigation on type of atmosphere (nitrogen and oxygen) showed no significant effect on the thermal stability of the blends especially at low temperatures. However, oxygen results in formation of a high‐temperature shoulder in the TGA curves. This shoulder is attributed to degradation of cross‐linked structures formed during the TGA heating scan.

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A Study of the Mechanical and Fracture Behavior of Jute‐Fabric‐Reinforced Clay‐Modified Thermoplastic Starch‐Matrix Composites
Authors: Ray Dipa , Sengupta Suparna , Sengupta Siba P. , Mohanty Amar K. , Misra Manjusri
Published: September 2007

Starch/poly(vinyl alcohol) films plasticized with glycerol were prepared by a solution‐casting method and were used as the matrix material for making jute‐fabric‐reinforced starch‐based composites. Four sets of composites were prepared with a variation in the matrix composition, all having 40 wt.‐% jute fabric as the reinforcement. The mechanical properties were superior in the case of the matrices containing a higher amount of starch. DMA was done to investigate the nature of bonding at the interface. The fracture surfaces were examined by SEM. Intimate bonding of the jute fibers with the matrix was evident. The clay‐filled matrices displayed a flat crack surface without any plastic deformation.

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Iterative solution of Hermite boundary integral equations
Authors: Gray L. J. , Nintcheu Fata S. , Ma D.
Published: September 2007

An efficient iterative method for solution of the linear equations arising from a Hermite boundary integral approximation has been developed. Along with equations for the boundary unknowns, the Hermite system incorporates equations for the first‐order surface derivatives (gradient) of the potential, and is therefore substantially larger than the matrix for a corresponding linear approximation. However, by exploiting the structure of the Hermite matrix, a two‐level iterative algorithm has been shown to provide a very efficient solution algorithm. In this approach, the boundary function unknowns are treated separately from the gradient, taking advantage of the sparsity and near‐positive definiteness of the gradient equations. In test problems, the new algorithm significantly reduced computation time compared with iterative solution applied to the full matrix. This approach should prove to be even more effective for the larger systems encountered in three‐dimensional analysis, and increased efficiency should come from pre‐conditioning of the non‐sparse matrix component. Published in 2007 by John Wiley & Sons, Ltd.
Computing bounds to real eigenvalues of real‐interval matrices
Authors: Leng Huinan , He Zhiqing , Yuan Quan
Published: September 2007

In this study, a new method with algorithms for computing bounds to real eigenvalues of real‐interval matrices is developed. The algorithms are based on the properties of continuous functions. The method can provide the tightest eigenvalue bounds and improve some former research results. Numerical examples illustrate the applicability and effectiveness of the new method. Copyright © 2007 John Wiley & Sons, Ltd.
Time‐optimal control of flexible systems subject to friction
Authors: Kim Jae‐Jun , Kased Rajaey , Singh Tarunraj
Published: September 2007

This paper presents a technique for the determination of time‐optimal control profiles for rest‐to‐rest maneuvers of a mass–spring system, subject to Coulomb friction. A parameterization of the control input that accounts for the friction force, resulting in a linear analysis of the system is proposed. The optimality condition is examined for the control profile resulting from the parameter optimization problem. The development is illustrated on a single input system where the control input and the friction force act on the same body. The variation of the optimal control structure as a function of final displacement is also exemplified on the friction benchmark problem. Copyright © 2007 John Wiley & Sons, Ltd.
The heat‐shock protein 90 inhibitor, geldanamycin, induces apoptotic cell death in Epstein–Barr virus‐positive NK/T‐cell lymphoma by Akt down‐regulation
Authors: Jeon YK , Park CH , Kim K‐Y , Li YC , Kim J , Kim YA , Paik J‐H , Park B‐K , Kim C‐W , Kim Y‐N
Published: September 2007

NK/T‐cell lymphoma (NKTL) is strongly associated with latent Epstein–Barr virus (EBV) infection. Recently, latent membrane protein 1 (LMP1), an EBV oncoprotein, was reported to activate the phosphatidylinositol‐3 kinase (PI3K)/Akt pathway for cell survival. Because geldanamycin (GA) and its derivative, 17‐allylamino‐17‐demethoxygeldanamycin (17‐AAG), exhibit anti‐tumour activity by degrading HSP90 client proteins, including Akt, we investigated the effect of GA and 17‐AAG on the survival of NKTL cell lines. EBV‐positive NKTL cell lines, Hank‐1 and NK‐YS, and an EBV‐negative NK leukaemia cell line, NK‐L, were treated with PI3K and Akt inhibitors, GA, and 17‐AAG, and were subjected to apoptosis and cell viability assays, and immunoblot analysis. EBV‐positive B‐lymphoblastoid cell lines IM9 and LMP1‐transfected IM9 (IM9‐LMP1) were also included. Hank‐1 and NK‐YS cell viability was compromised and apoptosis was induced by LY294002 (PI3K inhibitor) or Akt inhibitor II. GA or 17‐AAG administration resulted in the apoptosis of NKTL cells, accompanied by Akt and pAkt down‐regulation, caspase 3 activation, and mitochondrial membrane potential disruption. The intrinsic level of pAkt was higher in EBV‐positive NKTL cells than in EBV‐negative NK‐L, and GA or 17‐AAG decreased the viability of NKTL cells more efficiently than NK‐L. Moreover, IM9‐LMP1 was more sensitive to Akt inhibitor II or HSP90 inhibitors than IM9. Importantly, GA showed little effect on the viability of normal peripheral NK cells as non‐neoplastic counterparts for comparison. In conclusion, this study suggests that the PI3K/Akt pathway is frequently activated in EBV‐positive NKTL and that therapeutic modalities based on targeting the PI3K/Akt pathway with HSP90 inhibitors could be useful for achieving NKTL control. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
c‐KIT is frequently mutated in bilateral germ cell tumours and down‐regulated during progression from intratubular germ cell neoplasia to seminoma
Authors: Biermann K , Göke F , Nettersheim D , Eckert D , Zhou H , Kahl P , Gashaw I , Schorle H , Büttner R
Published: September 2007

Testicular germ cell tumours (TGCTs) are the most frequent cancer type in young men; 5% of these patients develop a second TGCT in the contralateral testis. The pathogenesis of TGCT is closely linked to primordial germ cells (PGCs) or gonocytes. The receptor tyrosine kinase (c‐KIT) is necessary for migration and survival of PGCs and is expressed in intratubular neoplastic germ cells (IGCNUs) and seminomas. We studied the frequency of c‐KIT exon 11 and 17 mutations in 155 unilateral (108 seminomas and 47 non‐seminomas) and 22 bilateral (18 seminomas, two embryonal carcinomas, two IGCNU) cases. While no mutations were detected in exon 11, the mutation frequency in exon 17 was significantly higher in bilateral (14/22, 63.6%) compared to unilateral TGCT (10/155, 6.4%) (p < 0.001). Different activating mutations (Y823D, D816V, D816H and N822K) were detected in bilateral TGCT. Y823D mutation was identical in both testes in three cases and quantitative pyrosequencing showed that up to 76% of the cells analysed in tumour samples carried this mutation. One bilateral synchronous seminoma revealed a S821F mutation in one testis and a Y823D mutation contralaterally. To study the role of c‐KIT in TGCT progression, we compared its expression in 41 seminomas and adjacent IGCNUs. Immunohistochemical analysis revealed that c‐KIT expression was significantly reduced in seminomas compared to IGCNUs (p < 0.006) and that there were no significant changes in c‐KIT mRNA copy numbers in progressed compared to low‐stage seminomas. In summary, our study shows that patients with c‐KIT mutations are more prone to develop a bilateral TGCT and suggests that in a portion of bilateral TGCTs, c‐KIT mutations occur early during embryonal development, prior to the arrival of PGCs at the genital ridge. Furthermore, our findings show that c‐KIT down‐regulation occurs during the progression of IGCNU to seminoma. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Effect of Plasma Treatment on the Gas Permeability of Poly(4‐methyl‐2‐pentyne) Membranes
Authors: Shao Lei , Samseth Jon , Hägg May‐Britt
Published: September 2007

The surface of a poly(4‐methyl‐2‐pentyne) membrane was modified by plasma treatment using CCl4; the permeabilities of O2, N2, H2, CH4 and CO2 were measured before and after the plasma treatment, and the selectivities of O2/N2, H2/N2, CO2/N2, CO2/CH4 and H2/CH4 were calculated. The selectivities were found to be remarkably improved after plasma treatment while gas permeabilities decreased. The effect of the plasma conditions such as the treatment time and discharge power on the permeabilities of the membranes was investigated in detail. The surface of modified membranes was analyzed by XPS, and the contact angles of water on the membranes were measured by a contact‐angle goniometer.

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Adhesion Improvement of Plasma‐Polymerized Maleic Anhydride Films on Gold Using HMDSO/O2 Adhesion Layers
Authors: Chifen Anye N. , Jenkins A. Toby A. , Knoll Wolfgang , Förch Renate
Published: September 2007

The use of SiO2‐like layers as adhesion‐promoting inter‐layers between a reactive plasma polymer film and a gold substrate is compared to a self‐assembled monolayer of dodecanethiol and to bare gold. The chemical structure of the silicon oxide film is optimized by varying feed gas ratios and process input power. A 5 s oxygen plasma modification of the SiO2‐like film deposited from hexamethyldisiloxane has been found to be vital to prepare the surface for covalent bonding of the subsequently deposited reactive polymer layer. Film chemical structures and reactivity have been studied using IR reflection‐absorption spectroscopy, XPS, contact angle goniometry and SPR spectroscopy.

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Catalytic Effects of Metals on the Conversion of Methane in Gliding Discharges
Authors: Schmidt‐Szałowski Krzysztof , Krawczyk Krzysztof , Młotek Michał
Published: September 2007

Plasma‐catalytic methane conversion was studied under gliding‐discharge conditions using a mobile (spouted) catalytic bed of fine particles. A new model of the GD reactor was tested for the non‐oxidative methane coupling using alumina‐supported catalysts containing Cu, Ni, Ag or Pt resistant against the plasma action. C2 hydrocarbons, besides hydrogen, were the main products, with some amounts of non‐volatile substances (mainly soot). With Cu/Al2O3, Ni/Al2O3, Ag/Al2O3, and alumina beds, acetylene was mainly produced from the CH4 + H2 mixture with none or a minor share of other C2 hydrocarbons. Using Pt/Al2O3, an increased ethylene and ethane content was found with lower acetylene content.

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Treatment of Carbon Tetrafluoride with Gas Discharges
Authors: Pietsch Gerhard J. , Saveliev Anatoli B.
Published: September 2007

Waste gases from semiconductor industry contain perfluorocarbons, which cause global warming and therefore should be removed. There are several possibilities to do this, for example the treatment of the gas by thermal and non‐thermal plasmas, as well as by heating. In model gases containing up to 10 000 ppm CF4, destruction removal efficiencies of nearly 100% have been reached at atmospheric pressure using dielectric barrier and arc discharges. In order to reach high values, the dissociation products of CF4 must be bonded by reaction partners such as SiO2, CaO or H2O.

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Atmospheric Pressure PE‐CVD of Fluorocarbon Thin Films by Means of Glow Dielectric Barrier Discharges
Authors: Fanelli Fiorenza , d'Agostino Riccardo , Fracassi Francesco
Published: September 2007

Glow dielectric barrier discharges (GDBDs) fed with He‐C3F6 and He‐C3F8‐H2 gas mixtures were used to deposit fluorocarbon thin films. The deposition process was studied inside the GDBD existence domain as evaluated by electrical measurements. The composition and structure of the deposited coatings were investigated through Fourier Transform Infrared Spectroscopy, X‐ray Photoelectron Spectroscopy, Water Contact Angle measurements, and Scanning Electron Microscopy. He‐C3F6 gas mixtures generate fluorocarbon films with F/C ratio of 1.5 at deposition rates up to 34 nm · min−1, while with He‐C3F8‐H2 fed GDBDs it is possible to tune the F/C ratio of the coating from 1.5 to 0.6 and to change its cross‐linking degree by varying the hydrogen concentration in the gas feed. H2 addition promotes the increase of the deposition rate which is maximum for fluorocarbon‐to‐hydrogen ratio close to 1. Results of optical emission spectroscopy investigation of the plasma phase are also presented.

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Arc‐Free Atmospheric Pressure Cold Plasma Jets: A Review
Authors: Laroussi Mounir , Akan Tamer
Published: September 2007

Non‐thermal atmospheric pressure plasma jets/plumes are playing an increasingly important role in various plasma processing applications. This is because of their practical capability to provide plasmas that are not spatially bound or confined by electrodes. This capability is very desirable in many situations such as in biomedical applications. Various types of ‘cold’ plasma jets have, therefore, been developed to better suit specific uses. In this paper a review of the different cold plasma jets developed to date is presented. The jets are classified according to their power sources, which cover a wide frequency spectrum from DC to microwaves. Each jet is characterized by providing its operational parameters such as its electrodes system, plasma temperature, jet/plume geometrical size (length, radius), power consumption, and gas mixtures used. Applications of each jet are also briefly covered.

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Selective conversion of plasma glucose into CO2 by Saccharomyces cerevisiae for the measurement of 13C abundance by isotope ratio mass spectrometry: proof of principle
Authors: Rembacz Krzysztof P. , Faber Klaas Nico , Stellaard Frans
Published: September 2007

To study carbohydrate digestion and glucose absorption, time‐dependent 13C enrichment in plasma glucose is measured after oral administration of naturally occurring 13C‐enriched carbohydrates. The isotope enrichment of the administered carbohydrate is low (APE <0.1%) and plasma 13C glucose measurements are routinely determined with gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) or liquid chromatography/combustion/isotope ratio mass spectrometry (LC/C/IRMS). In this study, plasma glucose was converted into CO2 by an in‐tube reaction with yeast permitting direct measurement of 13CO2 in the headspace. Saccharomyces cerevisiae incubated under anaerobic conditions was able to convert sufficient glucose into CO2 to produce a consistent CO2 peak in IRMS with little variation in peak area and precise δ13CPDB values for corn glucose: −11.40 ± 0.16‰, potato glucose: −25.17 ± 0.13‰, and plasma glucose: −26.29 ± 0.05‰. The measurement showed high linearity (R2 = 0.999) and selectivity and was not affected by the glucose concentration in the tested range of 5–15 mM. Comparison with GC/C/IRMS showed a good correlation of enrichment data: R2 > 0.98 for both sources of glucose and plasma samples. Commercially available, instant dried baker's yeast was qualitatively and quantitatively comparable with freshly prepared yeast: R2 > 0.96, slope 1.03 and 1.08 for glucose solutions and plasma, respectively. Thus, yeast conversion of plasma glucose into CO2 and 13C measurement applying a breath 13CO2 analyzer is an inexpensive, simple and equally accurate alternative to the more expensive and laborious GC/C/IRMS and LC/C/IRMS measurements. Copyright © 2007 John Wiley & Sons, Ltd.
A new approach to overcome natural cholesterol interference during simultaneous determination of two stable isotope‐enriched cholesterol tracers in human plasma
Authors: Wolff E. , Vergnes M. F. , Kaloustian J. , Abou L. , Mikail C. , Lairon D. , Portugal H. , Nicolay A.
Published: September 2007

We have developed a validated gas chromatography/mass spectrometry (GC/MS) method with two labelled cholesterol tracers, i.e. 2H4 ([2H4]‐Chol) and 2H7 ([2H7]‐Chol) enriched moieties, with a new way of calculating the abundance of labelled cholesterol in plasma without natural cholesterol interference. The isotopomers of the analytes could interfere during analysis. Elimination of these interferences can be performed by the blank or mathematical subtraction method. Validation was performed with the two interference elimination methods. For both methods, linearity was obtained in the range 5 × 10−4 to 10−2 mM for both labelled cholesterol moieties. In the same range, repeatability and reproducibility were less than 6.5% and 7.5% for [2H4]‐Chol and [2H7]‐Chol, respectively. Accuracy was about 100% and recoveries always included 100% for the two labelled cholesterols. We demonstrate that measurement of blank plasma is not necessary when using the validated abundance isotope calculation method. This saves time, reagent and samples. This calculation strategy can be extrapolated to comparable tracer approaches. Copyright © 2007 John Wiley & Sons, Ltd.
Quantitative comparison of a flared and a standard heated metal capillary inlet with a voltage‐assisted air amplifier on an electrospray ionization linear ion trap mass spectrometer
Authors: Dixon R. Brent , Muddiman David C.
Published: September 2007

The performance characteristics (i.e., ion abundance and electrospray ion current) of a flared and blunt‐ended heated metal capillary were evaluated with a voltage‐assisted air amplifier on a linear ion trap mass spectrometer (LTQ‐MS). The results demonstrated that a standard capillary afforded higher ion abundance than a flared capillary, thus further work is necessary to investigate conditions for which significant benefits with the flared capillary will be observed. The compatibility of a voltage‐assisted air amplifier is explored for both types of capillaries and in all cases resulted in improved ion abundance and spray current. Copyright © 2007 John Wiley & Sons, Ltd.
RNA interference and HIV‐1 infection
Authors: Kanzaki Luis Isamu Barros , Ornelas Socrates Souza , Argañaraz Enrique R.
Published: September 2007

Life‐prolonging antiretroviral therapy remarkably reduces viral load, but it does not eradicate the virus. An important obstacle preventing virus clearance is the presence of latent virion reservoirs in the host. However, new promising antiviral approaches are emerging, and a number of host cell factors involved in the disease progression and control of HIV‐1 replication have been recently discovered. For instance, the RNA interference (RNAi) mechanism, besides many functions conserved throughout evolution, works as a defence mechanism against noxious transcripts which may provide a new tool to block viral replication. The recent definition of basic RNAi mechanisms, as well as the discovery of micro RNAs (microRNAs) encoded by the host cell genome and by HIV‐1, also suggest that RNAi may be involved in the control of HIV replication. Copyright © 2007 John Wiley & Sons, Ltd.
Sensitivity analysis of progression‐free survival with dependent withdrawal
Authors: Ruan Ping K. , Gray Robert J.
Published: September 2007

We develop a sensitivity analysis method for comparing treatment‐specific distributions where the endpoint is progression‐free survival (PFS). The censoring process may be informative due to selective patient withdrawal, which occurs whenever disease evaluation has been discontinued without progression being documented. The sensitivity analysis explores the effects of the dependence between patient withdrawal and progression time using a conditional probability model which incorporates a set of sensitivity parameters. We propose an EM algorithm for estimation of PFS under the model for dependence and construct log‐rank‐type score statistics from the estimated distributions. Bootstrap procedures are used to estimate the variance of the score statistic. We also extend the methodology to incorporate additional survival information, which may be available on the cases who were withdrawn. An Eastern Cooperative Oncology Group (ECOG) advanced lung cancer clinical trial (E1594) is used to illustrate the methodology. Copyright © 2007 John Wiley & Sons, Ltd.
Fixed vs random effects meta‐analysis in rare event studies: The Rosiglitazone link with myocardial infarction and cardiac death
Authors: Shuster Jonathan J. , Jones Lynn S. , Salmon Daniel A.
Published: September 2007

Meta‐analyses can be powerful tools to combine the results of randomized clinical trials and observational studies to make consensus inferences about a medical issue. It will be demonstrated that a common practice of testing for homogeneity of effect size, and acting upon the inference to decide between fixed vs random effects, can lead to potentially misleading results. A by‐product of this paper is a new ratio estimator approach to random effects meta‐analysis of a large set of studies with low event rates. As a case study, we shall use the recent Rosiglitazone example, where diagnostic testing failed to reject homogeneity, leading the investigators to use fixed effects. The results for the fixed and random effects analyses are discordant. In the fixed (random) effects analysis, the p‐values for myocardial infarction were 0.03 (0.11) while those for cardiac death were 0.06 (0.0017). Had the fixed effects analysis controlled the study error for multiple testing via a Bonferonni correction, the joint 95+ per cent confidence rectangle for the two outcomes would have included odds ratios of (1.0, 1.0). For the Rosiglitazone example, random effects analysis, where all studies receive the same weight, is the superior choice over fixed effects, where two large studies dominate. Copyright © 2007 John Wiley & Sons, Ltd.
Changes in left heart hemodynamics after technically successful in‐utero aortic valvuloplasty
Authors: Selamet Tierney E. S. , Wald R. M. , McElhinney D. B. , Marshall A. C. , Benson C. B. , Colan S. D. , Marcus E. N. , Marx G. R. , Levine J. C. , Wilkins‐Haug L. , Lock J. E. , Tworetzky W.
Published: September 2007

Objective

Severe aortic stenosis in the mid‐gestation fetus can progress to hypoplastic left heart syndrome (HLHS). @ In‐utero aortic valvuloplasty is an innovative therapy to promote left ventricular growth and function and potentially to prevent HLHS. This study evaluated the effects of mid‐gestation fetal balloon aortic valvuloplasty on subsequent fetal left ventricular function and left heart Doppler characteristics.

Methods

We reviewed fetuses with aortic stenosis that underwent attempted in‐utero aortic valvuloplasty between 2000 and 2006. Pre‐intervention and the latest post‐intervention fetal echocardiograms were analyzed to characterize changes in left heart function and Doppler characteristics in utero.

Results

Forty‐two fetuses underwent attempted aortic valvuloplasty during the study period, 12 of which were excluded from analysis secondary to inadequate follow‐up data, termination or fetal demise. Study fetuses (n = 30) underwent pre‐intervention echocardiography at a median gestational age of 23 weeks, and were followed for a median of 66 ± 23 days post‐intervention. In 26 fetuses, aortic valvuloplasty was technically successful. Among these 26, left heart physiology was abnormal pre‐intervention and improved or normalized after intervention in most cases: biphasic mitral inflow was present in 5/25 (20%) cases pre‐intervention and in 21/23 (91%) post‐intervention (P < 0.001); moderate or severe mitral regurgitation was present in 14/26 (54%) cases pre‐intervention and in 5/23 (22%) post‐intervention (P = 0.02); bidirectional flow across the patent foramen ovale was present in 0/26 cases pre‐intervention and in 6/25 (24%) post‐intervention (P = 0.01); antegrade flow in the transverse arch was present in 0/25 cases pre‐intervention and in 17/26 (65%) post‐intervention (P < 0.001). The left ventricular ejection fraction increased from 19 ± 10% pre‐intervention to 39 ± 14% post‐intervention (P < 0.001). These changes were not observed in control fetuses (n = 18).

Conclusion

Fetal aortic valvuloplasty, when technically successful, improves left ventricular systolic function and left heart Doppler characteristics. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Analytical Control of Experimental Extraction of Oilseed
Authors: William H. King
Published: September 2007

A study was made of methods for measuring relevant components at different stages of an experimental process for mixed solvent extraction of raw cottonseed flaked meats. The principles discussed should apply to other complex oilseed separation procedures.
Selection of internal standards for determining quantitative recovery of isoprenoid acids after urea complexing
Authors: Ackman R. G. , Sipos J. C. , Hooper S. N. , Dube G.
Published: September 2007

Various types of esters are considered as internal standards for the quantitative gas liquid Chro‐matographic determination of isoprenoid fatty acids after urea complex treatment of esters of total or saturated fatty acids. It is shown that aromatic esters are potentially unsuitable because of on‐column losses with polyester columns. Two classes of ali‐phatic esters, either of 2‐ethyl‐l‐hexanol, or of 3‐cyclohexylpropionic acid, have been evaluated as satisfactory and certain gas liquid Chromatographic retention data is given to show which ester might be selected for a particular application.
Aminimides: III antimicrobial effect of various hexadecyl and quaternary derivatives
Authors: Kabara Jon J.
Published: September 2007

Aminimides, a new class of surfactants, have been screened for in vitro antimicrobial activity. Greatest activity against gram (+) and yeast organisms is achieved when a chain length of C16 is reached. This generalization is true whether or not the chain length is joined to the imide or amine group. The type of functional group associated with the surfactant is less important than chain length. Gram (‐) organisms do not fit this generalization, since shorter (<C16) rather than longer chain derivatives are more active. The importance of surfactant chain length to biodegrad‐ability is discussed.
Quantitative analysis of furanoid fatty acids in crude and refined cod liver oil
Authors: Scrimgeour Charles M.
Published: September 2007

A method is described for determining the furan‐oid fatty acids F1‐F6 in cod liver oil using squalane as an internal standard added prior to isolation of the F esters by silver ion chromatography (Ag+ TLC) and urea crystallization. The F acids amount to about 1% of the oil and can be determined with an accuracy of ± 15%. There is no significant change in the amount of F acids after refining.
Political Instability and Economic Development in Sub-Saharan Africa: Further Evidence
Authors: Mbaku John Mukum
Published: September 2007

After more than three decades of independence, many countries in Sub-Saharan Africa have not yet developed stable political systems. Since the 1960s, when African countries began to achieve independence, many of them have encountered significant levels of institutional instability. In recent years, political violence has emerged as the most common method of governmental change. In this study, the effects of political violence on economic and human development in Sub-Saharan Africa are examined. It is seen that political instability is a significant constraint to the improvement of the human condition in the region.