bluuebunny/crossref_metadata_2025 huggingface dataset:
Decimalization, trading costs, and information transmission between ETFs and index futures
Authors: Chou Robin K. , Chung Huimin
Published: December 2005

The impact of changes in trading costs, due to decimalization, on informed trading and speed of information transmission between exchange‐traded funds (ETFs) and their corresponding index futures is examined. ETFs began to trade in decimals on January 29, 2001, and index futures continued to trade in their original tick sizes. The focus is on whether the decrease in the minimum tick size of ETFs influences the relative performances of these two types of index instruments in the price‐discovery process. It is found that for ETFs, the trading activity increases, but the market depth drops significantly after decimalization. The spreads for ETFs generally decrease, but the adverse selection component of ETF spreads increases. Furthermore, after decimalization, ETFs start to lead index futures in the price‐discovery process and its share of information also increases. Although index futures still assume a dominant role in information discovery, the information content of the ETFs' prices improves significantly after decimalization. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:131–151, 2006
Jumping hedges: An examination of movements in copper spot and futures markets
Authors: Chan Wing H. , Young Denise
Published: December 2005

Price risk is an important factor for both copper purchasers, who use the commodity as a major input in their production process, and copper refiners, who must deal with cash‐flow volatility. Information from NYMEX cash and futures prices is used to examine optimal hedging behavior for agents in copper markets. A bivariate GARCH‐jump model with autoregressive jump intensity is proposed to capture the features of the joint distribution of cash and futures returns over two subperiods with different dominant pricing regimes. It is found that during the earlier producerpricing regime this specification is not needed, whereas for the later exchange pricing era jump dynamics stemming from a common jump across cash and futures series are significant in explaining the dynamics in both daily and weekly data sets. Results from the model are used to under‐take both within‐sample and out‐of‐sample hedging exercises. These results indicate that there are important gains to be made from a time‐varying optimal hedging strategy that incorporates the information from the common jump dynamics. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:169–188, 2006
Microsatellites versus single‐nucleotide polymorphisms in confidence interval estimation of disease loci
Authors: Papachristou Charalampos , Lin Shili
Published: December 2005

With cost‐effective high‐throughput Single Nucleotide Polymorphism (SNP) arrays now becoming widely available, it is highly anticipated that SNPs will soon become the choice of markers in whole genome screens. This optimism raises a great deal of interest in assessing whether dense SNP maps offer at least as much information as their microsatellite (MS) counterparts. Factors considered to date include information content, strength of linkage signals, and effect of linkage disequilibrium. In the current report, we focus on investigating the relative merits of SNPs vs. MS markers for disease gene localization. For our comparisons, we consider three novel confidence interval estimation procedures based on confidence set inference (CSI) using affected sib‐pair data. Two of these procedures are multipoint in nature, enabling them to capitalize on dense SNPs with limited heterozygosity. The other procedure makes use of markers one at a time (two‐point), but is much more computationally efficient. In addition to marker type, we also assess the effects of a number of other factors, including map density and marker heterozygosity, on disease gene localization through an extensive simulation study. Our results clearly show that confidence intervals derived based on the CSI multipoint procedures can place the trait locus in much shorter chromosomal segments using densely saturated SNP maps as opposed to using sparse MS maps. Finally, it is interesting (although not surprising) to note that, should one wish to perform a quick preliminary genome screening, then the two‐point CSI procedure would be a preferred, computationally cost‐effective choice. Genet. Epidemiol. 30:3–17, 2006. © 2005 Wiley‐Liss, Inc.
Influence of Detritus on the Structure of the Invertebrate Community in a Small Portuguese Stream
Authors: González M. , Graça Manuel A. S.
Published: December 2005

This study tests if the coarse particulate organic matter (CPOM) mass was related to the invertebrate community structure in riffles and sandy pools of a fourth‐order reach of a stream after partialling out the effects of physical characteristics of the sampled patches. Diversity and structure of the assemblages differed between habitats. In both, CPOM mass was positively correlated with total density and with all functional feeding groups excepting filterers. Redundancy analyses and variance partitioning procedures indicated that (1) CPOM stocks influenced the assemblage structure in both habitats, and (2) most of those effects were unrelated to sampling date and measured physical characteristics (water depth in sandy pools, Froude number and substrate composition in riffles) of the patches. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Experimental investigation of interfaces in hydroxyapatite/polyacrylic acid/polycaprolactone composites using photoacoustic FTIR spectroscopy
Authors: Verma Devendra , Katti Kalpana , Katti Dinesh
Published: December 2005

Molecular interactions in hydroxyapatite (HAP) polymer composites have been studied using photoacoustic spectroscopy. HAP is mineralized by wet precipitation under two conditions: first is in the absence of polyacrylic acid (PAAc) (ex‐situ HAP) and second in the presence of PAAc (in‐situ HAP). Porous and solid composites of ex‐situ and in‐situ HAP with polycaprolactone (PCL) have also been made to evaluate their applicability as bone scaffolds. Photoacoustic Fourier transform infrared (PA‐FTIR) spectroscopy studies indicate that both in‐situ and ex‐situ HAP have HPO42− in their structure, which leads to Ca2+ deficiency. During crystallization of in‐situ HAP, PAAc dissociates to form carboxylate ions, which binds to calcium ions and act as suitable site for nucleation for HAP crystallization. PA‐FTIR spectra of porous and solid composites indicate that porous composites adsorb more water, which is hydrogen bonded with carbonyl of PCL. Mechanical tests on solid samples indicate that ex‐situ HAP/PCL composites have higher elastic modulus than in‐situ HAP/PCL composites. However, in case of porous composites, in‐situ HAP/PCL composites are found to have higher elastic modulus. In‐situ HAP is chemically and structurally different from ex‐situ HAP. This modified HAP causes variation in microstructure of porous composite and hence alteration of its load transfer mechanisms and hence mechanical properties. © 2005 Wiley Periodicals, Inc., J Biomed Mater Res, 2006
Intact surface of bioactive glass S53P4 is resistant to osteoclastic activity
Authors: Wilson Timothy , Parikka Vilhelmiina , Holmbom Johanna , Ylänen Heimo , Penttinen Risto
Published: December 2005

Bioactive glass reacts with body fluids and is gradually dissolved in tissues and in cell cultures. We investigated whether osteoclasts contribute to this process, by culturing newborn rat bone‐marrow cells containing osteoclasts on polished bioactive glass plates (glass S53P4). The cultures were inspected at days 1–5 and stained for alkaline phosphatase (ALP) to demonstrate osteoblasts and for tartrate resistant acid phosphatase (TRAP) to visualize osteoclasts. Nonosteoclastic cells proliferated several‐fold both on bioactive glass and on plastic, whereas osteoclasts and their precursors matured into multicellular giant cells and degenerated. Most cells on bioactive glass became ALP‐positive, whereas on plastic the majority of cells remained ALP‐negative. Osteoclasts survived on bioactive glass for 4–5 days, whereas on plastic they degenerated and disappeared after 3 days. Condensed nuclei indicating apoptosis were detected both in degenerating osteoclasts and osteoblasts. The surface of the bioactive glass reacted rapidly forming rounded pits, erosions, and cracks within 24 h in areas occupied by osteoblasts. Light microscopy and scanning electron micrographs demonstrated, however, a smooth surface below the cytoplasm of osteoclasts. This indicates that when applied on an intact bioactive glass surface, osteoclasts were unable to dissolve the glass material within this culture period. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Mechanism of in vivo DNA transport into cells by electroporation: electrophoresis across the plasma membrane may not be involved
Authors: Liu Feng , Heston Steve , Shollenberger Lisa M , Sun Bin , Mickle Marlin , Lovell Michael , Huang Leaf
Published: December 2005

Background

Recently, in vivo gene transfer with electroporation (electro‐gene transfer) has emerged as a leading technology for developing nonviral gene therapies and nucleic acid vaccines. The widely hypothesized mechanism is that electroporation induces structural defects in the membrane and provides an electrophoretic force to facilitate DNA crossing the permeabilized membrane. In this study, we have designed a device and experiments to test the hypothesis.

Methods

In this study, we have designed a device that alternates the polarity of the applied electric field to elucidate the mechanism of in vivo electro‐gene transfer. We also designed experiments to challenge the theory that the low‐voltage (LV) pulses cannot permeabilize the membrane and are only involved in DNA electrophoresis, and answer the arguments that (1) the reversed polarity pulses can cause opposing sides of the cell membrane to become permeabilized and provide the electrophoresis for DNA entry; or (2) once DNA enters cytoplasmic/endosomal compartments after electroporation, it may bind to cellular entities and might not be reversibly extracted. Thus a gradual buildup of the DNA in the cell still seems quite possible even under the condition of the rapid reversal of polarity.

Results

Our results indicate that electrophoresis does not play an important role in in vivo electro‐gene transfer.

Conclusions

This study provides new insights into the mechanism of electro‐gene transfer, and may allow the definition of newer and more efficient conditions for in vivo electroporation. Copyright © 2005 John Wiley & Sons, Ltd.
Studies on thermionic ionisation detection in comprehensive two‐dimensional gas chromatography
Authors: Ryan Danielle , Marriott Philip
Published: December 2005

This study explores the application of specific thermionic ionisation detection in comprehensive 2‐D GC (GC×GC) and represents the first report of GC×GC with nitrogen phosphorus detection (GC×GC‐NPD). Of particular interest is the performance of the NPD with respect to peak parameters of asymmetry and sensitivity. Since GC×GC produces much narrower peaks than obtained with fast GC (e. g. 100 ms vs. < 1 s) the effect of detector response time and any lack of symmetry arising from the detection step is important if peak separation (resolution) is to be maintained. It was observed that detector gas flows had a significant impact on peak asymmetry and peak magnitude, and that optimisation of the detector was critical, particularly for complex sample analysis by GC×GC‐NPD. Peak asymmetries ranging from As = 1.8 to 8.0 were observed under different conditions of detector gas flows. Comparison of GC×GC‐NPD with GC×GC‐flame ionisation detection (FID) showed the former to be approximately 20 times more sensitive for the detection of nitrogen‐containing methoxypyrazines analytes, and GC×GC‐NPD had a larger linear detection range compared to GC×GC‐FID. Furthermore, comparison of GC×GC‐NPD and GC×GC‐TOFMS chromatograms for the analysis of coffee headspace demonstrated the benefits of selective detection, ultimately realised in a comparatively simplified contour plot.
On‐line redox derivatization liquid chromatography using double separation columns and one derivatization unit
Authors: Saitoh Kazunori , Yamada Noriko , Ishikawa Eri , Nakajima Hizuru , Shibukawa Masami
Published: December 2005

A new on‐line redox derivatization technique using double separation columns and one redox derivatization unit was presented for enhancement of separation selectivity of HPLC. This on‐line redox derivatization HPLC system consisted of two separation columns and one redox derivatization unit placed between them. The redox reaction proceeds in the derivatization unit so that an analyte compound migrates as its original form in the first column, while as its oxidized or reduced form in the second column. The retention of the analytes is controlled by the lengths of the two separation columns in this system. We adopted a small column packed with porous graphitic carbon (PGC) as a redox derivatization unit and two C18 silica columns treated with hexadecyltrimethylammonium chloride as separation columns. The redox activity of PGC and the efficiency of the on‐line redox derivatization HPLC system for enhancement of separation selectivity were investigated using EDTA complexes of some metal ions. Original untreated PGC and PGC treated with hydrogen peroxide completely oxidized Co(II)‐EDTA and converted it to Co(III)‐EDTA, while the other metal complexes eluted as their original oxidation states throughout the system. Selective separation and determination of cobalt in a reference copper alloy by the developed method were demonstrated.
Polymer‐based monolithic microcolumns for hydrophobic interaction chromatography of proteins
Authors: Hemström Petrus , Nordborg Anna , Irgum Knut , Svec Frantisek , Fréchet Jean M. J.
Published: December 2005

Monolithic capillary columns for hydrophobic interaction chromatography (HIC) have been prepared by thermally initiated, single‐step in situ polymerization of mixtures of monovinyl monomers including butyl methacrylate and/or 2‐hydroxyethyl methacrylate, with a divinyl crosslinker glycerol dimethacrylate or 1,4‐butanediol dimethacrylate using two different porogen systems. Two porogenic solvent mixtures were used; one “hydrophilic”, consisting of water, butanediol, and propanol, and one “hydrophobic,” comprising dodecanol and cyclohexanol. The porous structures of the monoliths were characterized and their performance was demonstrated with a separation of a mixture of myoglobin, ribonuclease A, and lysozyme under conditions typical of HIC.
Capillary electrophoretic separation of inorganic sulfur–sulfide, polysulfides, and sulfur‐oxygen species
Authors: Petre Catalin Florin , Larachi Faïçal
Published: December 2005

A CE protocol was developed for the identification and separation of inorganic polysulfides simultaneously with other inorganic sulfur‐bearing species coexisting in aqueous hydrosulfide/sulfur solutions. The electrophoretic separation of thiosulfate, sulfate, hydrosulfide, sulfite, tetrathionate, and polysulfides was achieved at pH values between 8.2 and 12.2. The peaks attributed to the polysulfide species were strongly sensitive to pH. CE analysis of hydrosulfide/sulfur solutions at different pH values permitted possible identification of two forms of polysulfides: S42– and S32–. Upon exposure to air at ambient temperature, thiosulfate was the main oxidation product of hydrosulfide/sulfur solutions mainly in the first 60 min, when hydrosulfide was rapidly consumed. Analysis of the oxidation reaction products provided retrospectively tentative evidence that the peaks separated and identified as tri‐ and tetrasulfide may be ascribed to polysulfides.
Preparation and properties of isobutylene–isoprene rubber–clay nanocomposites
Authors: Kato Makoto , Tsukigase Azusa , Tanaka Hiromitsu , Usuki Arimitsu , Inai Isamu
Published: December 2005

Isobutylene isoprene rubber (IIR)‐clay nanocomposites have been prepared successfully by melt intercalation with maleic anhydride‐grafted IIR (Ma‐g‐IIR) and organophilic clay. In IIR‐clay nanocomposites, the silicate layers of the clay were exfoliated and dispersed into the monolayer. The nanocomposites exhibited greater gas barrier properties compared with those of Ma‐g‐IIR. When 15 phr clay was added, gas barrier properties were 2.5 times greater than those of Ma‐g‐IIR. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1182–1188, 2006
Rasch analysis of the dimensional structure of the Hospital Anxiety and Depression Scale
Authors: Smith A.B. , Wright E.P. , Rush R. , Stark D.P. , Velikova G. , Selby P.J.
Published: December 2005

The Hospital Anxiety and Depression Scale (HADS) has been used extensively in cancer patients to identify psychological distress. Reports of the factor structure and screening performance of the instrument vary. Rasch models allow an assessment of the structure of a questionnaire by identifying item fit. Removal of misfitting items may improve both the dimensionality and efficacy of screening questionnaires.

A Rasch analysis of the HADS‐T and subscales was used to explore the factor structure, dimensionality and screening efficacy. A total of 1855 patients completed a touchscreen version of the HADS, including 381 patients who had received a psychiatric interview (SCAN/PSE). These data were analysed using Rasch models, and the screening efficacy at identifying cases of psychological distress and anxiety and depression evaluated.

The results demonstrated that the structure of the HADS‐T and subscales was unidimensional. Three items from the HADS‐T, and one from each of the subscales demonstrated misfit. Screening efficacy for the HADS‐T and subscales was modest. However, removal of misfitting items had little impact on screening, demonstrating that items could potentially be omitted, if required. The item range covered a narrow spectrum of psychological distress, predominantly higher levels of distress. Additional items have to be added if screening for moderate to mild distress is to be improved for cancer patients. Copyright © 2005 John Wiley & Sons, Ltd.
Gene therapy for prostate cancer: Current strategies and new cell‐based approaches
Authors: MacRae E.J. , Giannoudis A. , Ryan R. , Brown N.J. , Hamdy F.C. , Maitland N. , Lewis C.E.
Published: December 2005

Prostate cancer is the most commonly diagnosed cancer in adult males in the Western world. It accounts for one in ten cancer cases and is the second leading cause of cancer death in men, after lung cancer. A number of curative treatments are available for patients with localized prostate cancer such as radical prostatectomy, radiotherapy, or brachytherapy. However, a proportion of these men will develop progressive disease, and some will present de novo with advanced and metastatic prostate cancer, which is amenable to palliation only with androgen‐withdrawal therapy. Most of these patients will eventually develop hormone refractory disease which is incurable, and for whom gene therapy, if feasible may develop as an alternative treatment option. In this review we discuss the gene therapy vectors and strategies that are currently in use, new cell‐based approaches, discuss their advantages and disadvantages, and review the potential or proven pre‐clinical and clinical efficacy in prostate cancer models/patients. © 2005 Wiley‐Liss, Inc.
Directed evolution of the epidermal growth factor receptor extracellular domain for expression in yeast
Authors: Kim Yong‐Sung , Bhandari Rashna , Cochran Jennifer R. , Kuriyan John , Wittrup K. Dane
Published: December 2005

The extracellular domain of epidermal growth factor receptor (EGFR‐ECD) has been engineered through directed evolution and yeast surface display using conformationally‐specific monoclonal antibodies (mAbs) as screening probes for proper folding and functional expression in Saccharomyces cerevisiae. An EGFR mutant with four amino acid changes exhibited binding to the conformationally‐specific mAbs and human epidermal growth factor, and showed increased soluble secretion efficiency compared with wild‐type EGFR. Full‐length EGFR containing the mutant EGFR‐ECD was functional, as assayed by EGF‐dependent autophosphorylation and intracellular MAPK signaling in mammalian cells, and was expressed and localized at the plasma membrane in yeast. This approach should enable engineering of other complex mammalian receptor glycoproteins in yeast for genetic, structural, and biophysical studies. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Solvent participation in Serratia marcescens endonuclease complexes
Authors: Chen Chuanying , Beck Brian W. , Krause Kurt , Pettitt B. Montgomery
Published: December 2005

The monomer and dimer of the bacterium Serratia marcescens endonuclease (SMnase) are each catalytically active and the two subunits of the dimer function independently of each other. Specific interfacial waters may play a role in stability, complex formation, and functionality. We performed molecular dynamics simulations of both a subunit of SMnase and its model built complex with DNA and analyzed the relation of the hydration sites to the catalytic mechanism. It was found that the binding of DNA has little influence on the global hydration properties of the protein, including occupancy and water residence time distributions. DNA and protein recognition in our model mainly involves direct contacts by hydrogen bond and hydrophobic interactions. Water‐mediated contacts exist, but are less common. Three interior water clusters were identified for SMnase. One cluster around the active site in the monomer–DNA complex shows relatively strong interactions between hydration sites as well as between the sites and the biomolecules. The simulated cluster properties agreed well with experimental data. The magnesium ion shows ligand exchange. Although Mg2+ keeps six ligands during the entire simulation, upon the binding of DNA, Asn119 loses its coordination with Mg2+, while one nonbridging oxygen of the phosphate of a DNA residue and two oxygen atoms of the side chain of Glu127 become the ligands. Waters in a nearby cluster exchange and participate in the resolvation of groups in the presence of DNA. Water thus not only participates in the cleavage of DNA but also can stabilize the transition state and the leaving groups in our model. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Conversion of type I 4:6 to 3:5 β‐turn types in human acidic fibroblast growth factor: Effects upon structure, stability, folding, and mitogenic function
Authors: Lee Jihun , Dubey Vikash Kumar , Somasundaram Thayumanasamy , Blaber Michael
Published: December 2005

Human acidic fibroblast growth factor (FGF‐1) is a member of the β‐trefoil superfold, a protein architecture that exhibits a characteristic threefold axis of structural symmetry. FGF‐1 contains 11 β‐turns, the majority being type I 3:5; however, a type I 4:6 turn is also found at three symmetry‐related locations. The relative uniqueness of the type I 4:6 turn in the FGF‐1 structure suggests it may play a key role in the stability, folding, or function of the protein. To test this hypothesis a series of deletion mutations were constructed, the aim of which was to convert existing type I 4:6 turns at two locations into type I 3:5 turns. The results show it is possible to successfully substitute the type I 4:6 turn by a type I 3:5 turn with minimal impact upon protein stability or folding. Thus, these different turn structures, even though they differ in length, exhibit similar energetic properties. Additional sequence swapping mutations within the introduced type I 3:5 turns suggests that the turn sequence primarily affects stability but not turn structure (which appears dictated primarily by the local environment). Although the results suggest that a stable, foldable β‐trefoil protein may be designed utilizing a single turn type (type I 3:5), a type I 4:6 turn at turn 1 of FGF‐1 appears essential for efficient mitogenic function. Proteins 2006. © 2005 Wiley‐Liss, Inc.
BLEVE blast by expansion‐controlled evaporation
Authors: van den Berg A.C. , van der Voort M.M. , Weerheijm J. , Versloot N.H.A.
Published: December 2005

This report presents a new method to calculate the blast effects originating from an exploding vessel of liquefied gas. Adequate blast calculation requires full knowledge of the blast source characteristics, that is, the release and subsequent evaporation rate of the flashing liquid. Because the conditions that allow explosive evaporation are not entirely clear and the evaporation rate of a flashing liquid is unknown, safe assumptions have been adopted as the starting point in the modeling. The blast effects from a boiling liquid expanding vapor explosion (BLEVE) are numerically computed by imposing the vapor pressure of a flashing liquid as boundary condition for the gas dynamics of expansion. The numerical modeling is quantitatively explored just for liquefied propane. In addition, this paper demonstrates that often an estimate of BLEVE blast effects is possible with very simple acoustic volume source expressions.

The modeling shows that the rupture of a pressure vessel containing a liquefied gas in free space develops a blast of significant strength only if the vessel nearly instantaneously disintegrates. Even if a rupture and the consequent release and evaporation of a liquefied gas extend over just a short period of time, the blast effects are minor. © 2005 American Institute of Chemical Engineers Process Saf Prog, 2006
Implementing inherently safer design in an existing plant
Authors: Hendershot Dennis C. , Sussman Jonathan A. , Winkler Gerald E. , Dill G. Lee
Published: December 2005

Although the best time for implementation of inherently safer design alternatives is during early process development and plant design, there are often opportunities to modify an existing plant to significantly enhance inherent safety. We will describe a modification to a bromine raw material handling facility, replacing an existing bulk storage tank with cylinders. Incident consequence analysis and quantitative risk analysis were used to understand the relative inherent safety characteristics of the design options. © 2005 American Institute of Chemical Engineers Process Saf Prog, 2006
Tribological characterisation of hard coatings with and without DLC top layer in fretting tests
Authors: Klaffke D.
Published: December 2005

The potential of coatings to protect components against wear and to reduce friction has led to a large variety of protective coatings. In order to check the success of coating modifications and to find solutions for different purposes, initial tests with laboratory tribometers are usually done to give information about the performance of a coating.

Different Ti‐based coatings (TiN, Ti(C,N), and TiAlN) and NiP were tested in comparison to coatings with an additional diamond‐like carbon (DLC) top coating. Tests were done in laboratory air at room temperature with oscillating sliding (gross slip fretting) with a ball‐on‐disc arrangement against a ceramic ball (Al2O3). Special attention was paid to possible effects of moisture (relative humidity). The coefficient of friction was measured on line, and the volumetric wear at the disc was determined after the test from microscopic measurements of the wear scar and additional profiles.

The friction and wear behaviour is quite different for the different coatings and depends more or less on the relative humidity. The DLC coating on top of the other coatings reduces friction and wear considerably. In normal and in moist air the coefficient of wear of the DLC top‐layer coating is significantly less than 10−6 mm3/Nm and the coefficient of friction is below 0.1. In dry air, however, there is a certain tendency to high wear and high friction. Copyright © 2006 John Wiley & Sons, Ltd.
Experimental device for the observation of rubbing surfaces during braking tests
Authors: François M. , Bulthé A.L. , Desplanques Y. , Degallaix G.
Published: December 2005

This paper introduces an experimental device, developed at the Laboratoire de Mécanique de Lille, specially designed for application in braking tests. The purpose of this device is to monitor the course of events on the rubbing surfaces during simulated braked stops and, in particular, the life and the dynamics of the third body. The usefulness of the device is demonstrated by the results of braking experiments performed on a grey cast iron disc for two different energies. These first experimental results show that the technique provides efficient and exploitable observations of tribological phenomena occurring on the wear‐track scale as well as on the microscopic scale. Copyright © 2006 John Wile & Sons, Ltd.
Coexistence of laryngeal squamous cell carcinoma and non-Hodgkin's lymphoma with nasopharyngeal involvement
Authors: Tezer Mesut Sabrı , Tuncel Ümit , Özlügedik Samet , Uzun Murat , Kulaçoğlu Sezer , Ünal Adnan
Published: December 2005

Laryngeal squamous cell carcinoma (SCC) is one of the most frequent malignancies in the head and neck region. The risk of multiple malignancies is reported as 2–11 per cent and most of the second primaries are SCCs. Lymphogenic tumours as second primaries are extremely rare. In this paper, we report a case of laryngeal SCC with synchronous non-Hodgkin's lymphoma and review the literature on the clinical and histopathological aspects of these malignancies.
Acute haemorrhage in patients with advanced head and neck cancer: value of endovascular therapy as palliative treatment option
Authors: Sesterhenn Andreas M , Iwinska-Zelder Joanna , Dalchow Carsten V , Bien Siegfried , Werner Jochen A
Published: December 2005

Aims: Acute or subacute haemorrhage is one of the most frightening complications in patients suffering from advanced head and neck cancer. Few articles report experience with superselective endovascular therapy for this purpose. Is endovascular therapy underestimated in the field of palliative head and neck cancer therapy? This study set out to investigate this question.

Patients and methods: A review was undertaken of the clinical courses of seven patients (six men, one woman) suffering from incurable, advanced head and neck cancer (four pharyngeal, two laryngeal, one neck) and treated with superselective endovascular strategies as an emergency procedure for acute bleeding.

Results: All patients were successfully treated without evidence of neurological complication. Patients reached a median survival of 20 weeks (range eight–168 weeks). Following endovascular treatment all patients were discharged from the hospital within several days. Three patients survived almost free of symptoms for several weeks and were able to stay at home with their families until their death.

Conclusion: We conclude that in the field of palliative care, superselective endovascular therapy deserves to be considered alongside standard treatment options for the management of acute haemorrhage from advanced head and neck cancer.
Laryngeal dysplasia: aetiology and molecular biology
Authors: Sadri Maziar , McMahon Jeremy , Parker Andrew
Published: December 2005

Laryngeal premalignancy is a common clinical concern. While tobacco has long been established as the principal identifiable aetiological factor, the last two decades have seen publications investigating a potential role for gastroesophageal reflux, gastrectomy and human papilloma virus. Furthermore, there have been major advances in our understanding of the molecular biology of cancer and premalignancy. Accompanying this increased understanding, significant efforts have been made to correlate the expression of molecular markers with the clinical course of premalignant laryngeal lesions.

This review summarizes current knowledge of the aetiological factors and molecular biology of laryngeal premalignancy. All aetiological factors, including molecular markers, are discussed separately and their possible role in the clinical course of these lesions is discussed.
Inflammatory nasal polyps: an unusual late complication of Silastic sheet repair of orbital floor fracture
Authors: Andrews A E , Hicklin L
Published: December 2005

Silastic implants are very widely used in surgical practice and are considered to be relatively inert. They do however present with complications, including infection, local foreign body inflammatory response, calcification, migration and failure of repair of the defect, which sometimes may necessitate explantation. Head and neck implants do present a special case, as complications can cause obstruction and disruption of function in small cavities. A pertinent history, clinical review and computed tomography scan are usually invaluable in obtaining a diagnosis. We present a rare case of migrated Silastic orbital sheet, presenting as a nasal polyp and causing maxillary antral pain and infection. A detailed search of the medical literature revealed no other such case.
Effect of nasal septal deviation on total ethmoid cell volume
Authors: Firat Ahmet Kemal , Miman Murat Cem , Firat Yezdan , Karakas Muammer , Ozturan Orhan , Altinok Tayfun
Published: December 2005

Background: The aim of this study was to evaluate the effect of nasal septal deviation (NSD) on ethmoid cell volume and to determine whether there was any correlation between NSD grade and ethmoid cell volume.

Methods: Forty computerized tomography (CT) scans from patients with rhinosinusitis symptoms with NSD were evaluated. Septal deviations were classified into three groups according to the degree of deviation on CT. Ethmoid cell volumes were measured and the relationship between NSD and ethmoid cell volume was investigated.

Results: There was a moderate but significant negative correlation between the septal deviation angle and the percentage of the ethmoid cell volumes (p = 0.001, r = −0.5152, r2 = 0.2654). Total ethmoid cell volume on the ipsilateral side compared with the contralateral side was found to decrease as the degree of NSD increased.

Conclusions: Nasal septal deviation affects the total ethmoid cell volume of the nasal cavity. The results of our study underline the role of ethmoid cell volume in the compensation mechanism equalizing the nasal cavity airflow changes due to NSD.
Leiomyosarcoma of the larynx
Authors: Rimmer J , Giddings C E B , Mady S
Published: December 2005

Smooth muscle tumours of the head and neck are rare. An unusual case of laryngeal leiomyosarcoma in a 69-year-old man is presented. Histological diagnosis of this tumour is difficult, and immunohistochemical studies are vital. Treatment is discussed, and should include local control with debulking, radiotherapy and long term follow up.
Applying the Five-Factor Model of Personality to the Exploration of the Construct of Risk-Taking in Obsessive-Compulsive Disorder
Authors: Rees Clare S. , Anderson Rebecca A. , Egan Sarah J.
Published: December 2005

Although there has been a long interest in the personality traits associated with obsessive-compulsive disorder (OCD), few studies have examined differences on normal, dimensional personality traits for individuals with OCD compared with other clinical disorders. The purpose of this study was to replicate and extend upon the work of Rector et al. (2002) who found unique associations between OCD and trait domains and facets of the five-factor model of personality (FFM) when compared with a clinical sample of depressed individuals. The current study compared individuals with a current diagnosis of OCD (n=21) with individuals with a current diagnosis of anxiety or depression but no OCD symptoms (n=39) on the Revised NEO Personality Inventory (NEO PI-R Form S). Of particular interest was whether individuals with OCD would differ from other clinically anxious/depressed individuals on the actions facet of the FFM, as this facet is known to be related to harm and risk avoidance, and previous research suggests specific relationships between these forms of avoidance and OCD. Individuals with OCD were found to have lower scores on the actions, competence and self-discipline facets. These results add further support to previous research that suggests unique associations between trait domains and facets of the FFM and OCD.
Surf zone currents over irregular bathymetry: Drifter observations and numerical simulations
Authors: Schmidt W. E. , Guza R. T. , Slinn D. N.
Published: December 2005

Surf zone currents over irregular bathymetry were observed with GPS‐tracked drifters and modeled with the depth‐integrated nonlinear shallow water equations. Trajectories of drifters released in 1–2 m depth sometimes defined rip currents and surf zone eddies, features that have been difficult to resolve with fixed instruments. The drifter‐delineated surf zone circulation evolved as the tidal level changed during each 4–6 hour deployment. In one case, as the tide dropped, a shore normal rip current present for the first 2 hours evolved to a more shore parallel flow. In a second case, on a rising tide a well‐developed bifurcated rip current was replaced by a weak, amorphous circulation. Rip current velocities were strongest near the surf zone edge and decayed by an order of magnitude within 2 surf zone widths from the shoreline. An eddy was observed to persist over a bathymetric depression within the surf zone for at least 1 hour. Observed and numerically simulated drifter trajectories define similar flow features, but the observed and modeled velocities differed by roughly a factor of 2, and flow evolution observed during roughly 0.5 m changes in tidal level were reproduced only if the simulated water levels varied by about 1 m. The alongshore momentum balance was spatially variable, with wave forcing balanced by pressure gradient, friction, and advective terms. The cross‐shore momentum balance was everywhere dominated by wave forcing and pressure gradient terms of about equal magnitude. In the vicinity of a simulated rip current the residual of the cross‐shore wave forcing and pressure gradient increased and was balanced by advection terms.
Centennial‐scale interactions between the carbon cycle and anthropogenic climate change using a dynamic Earth system model
Authors: Winguth A. , Mikolajewicz U. , Gröger M. , Maier‐Reimer E. , Schurgers G. , Vizcaíno M.
Published: December 2005

A complex Earth system model including atmosphere, ocean, ice sheets, marine carbon cycle and terrestrial vegetation was used to study the long‐term response (100–1000 yrs) of the climate to different increased atmospheric CO2 concentrations. A 3.2 K global mean surface temperature increase is simulated for a 3xCO2 experiment. The freshwater input by melting of the Greenland Ice Sheet due to global warming is of minor importance compared to hydrological changes in the atmosphere. Increased equatorial upwelling enhances the tropical outgassing of CO2 from the oceans, lowering the total marine carbon uptake by 16–22%. On land, carbon release due to increase in soil temperature reduces the anthropogenic carbon uptake from CO2 fertilization up to 43%. Thus, we show that both marine and terrestrial carbon cycle have a positive feedback on climate, which has to be considered for future carbon emission scenarios.
Nitrous oxide measurements during EIFEX, the European Iron Fertilization Experiment in the subpolar South Atlantic Ocean
Authors: Walter Sylvia , Peeken Ilka , Lochte Karin , Webb Adrian , Bange Hermann W.
Published: December 2005

We measured the vertical water column distribution of nitrous oxide (N2O) during the European Iron Fertilization Experiment (EIFEX) in the subpolar South Atlantic Ocean during February/March 2004 (R/V Polarstern cruise ANT XXI/3). Despite a huge build‐up and sedimentation of a phytoplankton bloom, a comparison of the N2O concentrations within the fertilized patch with concentrations measured outside the fertilized patch revealed no N2O accumulation within 33 days. This is in contrast to a previous study in the Southern Ocean, where enhanced N2O accumulation occurred in the pycnocline. Thus, we conclude that Fe fertilization does not necessarily trigger additional N2O formation and we caution that a predicted radiative offset due to a Fe‐induced additional release of oceanic N2O might be overestimated. Rapid sedimentation events during EIFEX might have hindered the build‐up of N2O and suggest, that not only the production of phytoplankton biomass but also its pathway in the water column needs to be considered if N2O radiative offset is modeled.
Parametric analysis of nightside conductance effects on inner magnetospheric dynamics for the 17 April 2002 storm
Authors: Liemohn Michael W. , Ridley Aaron J. , Brandt Pontus C. , Gallagher Dennis L. , Kozyra Janet U. , Ober Daniel M. , Mitchell Donald G. , Roelof Edmond C. , DeMajistre Robert
Published: December 2005

Numerous simulations were conducted in order to quantify the influence of nightside conductance morphology and intensity on the storm‐time ring current and plasmasphere. The study focused on the moderate magnetic storm of 17 April 2002. The simulation results were compared against measurements of the ring current and plasmasphere in order to assess the accuracy as a function of conductance parameter setting. In particular, three data sets were used: Dst*, plasmapause location as extracted from IMAGE EUV snapshots, and IMAGE HENA flux observations for the 39–60 keV energy range. While no single simulation conducted for this study proved itself to be the best overall match to the selected data sets, many things were learned from the simulations. The most important scientific finding is that there is an optimal conductance level for maximal ring current intensity. Too little conductance leads to large shielding potentials that effectively inhibit ring current growth, while too much conductance leads to continual flow‐through of the hot ions with no significant hot ion accumulation in the inner magnetosphere. It was found that the poleward shift of the high conductance region of the auroral oval was the most important factor affecting the data‐model comparisons. The peak intensity of the auroral oval conductance was also determined to be a significant factor affecting model accuracy. Tilting the dawnside location of the oval equatorward with respect to its duskside latitude had little effect on the results, as did the setting for the uniformly applied baseline conductance. The high‐latitude boundary condition for the potential solution was also found to have little influence on the results.
Thermospheric distribution of fast O(1D) atoms
Authors: Kharchenko V. , Dalgarno A. , Fox J. L.
Published: December 2005

Detailed calculations are carried out of the sources of energetic metastable O(1D) atoms in the atmosphere at altitudes between 80 km and 200 km, and the corresponding energy distribution functions are derived, taking account of energy transfer and quenching in collisions of the metastable atoms with the ambient atmospheric gas constituents. The energy relaxation of metastable oxygen atoms produced by O2 and O3 photolysis and O2+ dissociative recombination is determined by solving the time‐dependent Boltzmann equation. The O(1D) thermalization and quenching times are obtained as functions of the altitude. The steady state distributions of metastable O(1D) are computed and used for the determination of the parameters characterizing the nonthermal O(1D) atoms. The nonthermal atoms comprise 4–6% of the distribution, and their effective temperatures are larger by 25–46% than the local temperatures of the ambient gas. The role of hot metastable oxygen atoms in the production of vibrationally excited OH molecules is analyzed.
Major episodes of the hydrologic history in the region of Hesperia Planum, Mars
Authors: Ivanov M. A. , Korteniemi J. , Kostama V.‐P. , Aittola M. , Raitala J. , Glamoclija M. , Marinangeli L. , Neukum G.
Published: December 2005

The High Resolution Stereo Color camera (HRSC) data over Hesperia Planum and its surroundings reveal important details of geologic episodes and water‐related processes in this region. (1) The Noachian fluvial events of Hesperia Planum depression included accumulation of water and formation of a water/ice reservoir there. Later, the reservoir was depleted in several phases reflecting diminishing amounts of water. Climate changes and/or volcanism were important in these volatile releases. (2) The massive, 0.45–1.5 × 106km3, erosion from the Hesperia depression before the main lava eruption possibly resulted in thick, 0.5–1.5 km, deposits in Hellas Planitia. (3) Measurements of the flooded craters within Hesperia Planum provide the estimates of the thickness of lavas there, about 250–500 m. The final volume of lavas within Hesperia Planum (0.4–0.7 × 106km3) is comparable with the range of some terrestrial igneous provinces such as Columbia River Basalts. (4) Extended magmatism possibly triggered formation of the outflow channel in a few locations after the lava emplacement. During this episode, about 0.04 × 106km3of material (about 4.5–8.9% of the volume eroded in the episode of massive erosion) were removed. The thickness of the composite lava layer exposed on the walls of the outflow channels, a few hundreds of meters, corresponds well to the thickness estimates made by the measurements of the flooded craters. (5) Dispersed viscous flows (debris aprons, flow‐like deposits) reflect the final fluvial events. Viscous flows from the subsurface sources in the Southwestern trough associate with Dao, Niger, and Harmakhis Valles. These flows represent the final volatile discharge from the Hesperia reservoir that mostly was depleted by the earlier events of massive erosion and formation of the outflow channels. Viscous surface flows are mostly associated with Reull Vallis and probably reflect redistribution of volatiles related to the late episodes of evolution of this outflow channel.
The structural roles of a conserved small hydrophobic core in the active site and an ionic bridge in domain I of Delta class glutathione S-transferase
Authors: Vararattanavech Ardcharaporn , Prommeenate Peerada , Ketterman Albert J.
Published: December 2005

GSTs (glutathione S-transferases; E.C.2.5.1.18) are a supergene family of dimeric multifunctional enzymes that have a major role in detoxification pathways. Using a GST from the mosquito Anopheles dirus (adGSTD4-4), we have characterized the enzymatic and physical properties of Leu-6, Thr-31, Leu-33, Ala-35, Glu-37, Lys-40 and Glu-42. These residues generate two motifs located in the N-terminal domain (domain I) that are functionally conserved across GST classes. The aim of this study was to understand the function of these two motifs. The first motif is a small hydrophobic core in the G-site (glutathione-binding site) wall, and the second motif contains an ionic bridge at the N-terminus of the α2 helix and is also part of the G-site. The mutations in the small hydrophobic core appear to have structural effects, as shown by the thermal stability, refolding rate and intrinsic fluorescence differences. In the Delta class GST, interactions form an ionic bridge motif located at the beginning of the α2 helix. The data suggest that electrostatic interactions in the α2 helix are involved in α-helix stabilization, and disruption of this ionic bridge interaction changes the movement of the α2-helix region, thereby modulating the interaction of the enzyme with substrates. These results show that the small hydrophobic core and ionic bridge have a major impact on structural stabilization, as well as being required to maintain structural conformation of the enzyme. These structural effects are also transmitted to the active site to influence substrate binding and specificity. Therefore changes in the conformation of the G-site wall in the active site appear to be capable of exerting influences on the tertiary structural organization of the whole GST protein.