bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnosis of Anomalous Winter Temperatures over the Eastern United States during the 2002/03 El Niño
Authors: Goddard Lisa , Kumar Arun , Hoerling Martin P. , Barnston Anthony G.
Published: November 2006

The eastern United States experienced an unusually cold winter season during the 2002/03 El Niño event. The U.S. seasonal forecasts did not suggest an enhanced likelihood for below-normal temperatures over the eastern United States in that season. A postmortem analysis examining the observed temperatures and the associated forecast is motivated by two fundamental questions: what are these temperature anomalies attributable to, and to what extent were these temperature anomalies predictable? The results suggest that the extreme seasonal temperatures experienced in the eastern United States during December–February (DJF) 2002/03 can be attributed to a combination of several constructively interfering factors that include El Niño conditions in the tropical Pacific, a persistent positive Pacific–North American (PNA) mode, a persistent negative North Atlantic Oscillation (NAO) mode, and persistent snow cover over the northeastern United States. According to the simulations and predictions from several dynamical atmospheric models, which were not rigorously included in the U.S. forecast, much of the observed temperature pattern was potentially predictable.
Emergent Behavior and Uncertainty in Multimodel Climate Projections of Precipitation Trends at Small Spatial Scales
Authors: Good P. , Lowe J.
Published: November 2006

Aspects of model emergent behavior and uncertainty in regional- and small-scale effects of increasing CO2 on seasonal (June–August) precipitation are explored. Nineteen different climate models are studied. New methods of comparing multiple climate models reveal a clearer and more impact-relevant view of precipitation projections for the current century. First, the importance of small spatial scales in multimodel projections is demonstrated. Local trends can be much larger than or even have an opposing sign to the large-scale regional averages used in previous studies. Small-scale effects of increasing CO2 and natural internal variability both play important roles here. These small-scale features make multimodel comparisons difficult for precipitation. New methods that allow information from small spatial scales to be usefully compared across an ensemble of multiple models are presented. The analysis philosophy of this study works with statistical distributions of small-scale variations within climatological regions. A major result of this work is a set of emergent relationships coupling the small- and regional-scale effects of CO2 on precipitation trends. Within each region, a single relationship fits the ensemble of 19 different climate models. Using these relationships, a surprisingly large part of the intermodel variance in small-scale effects of CO2 is explainable simply by the intermodel variance in the regional mean (a form of pattern scaling). Different regions show distinctly different relationships. These relationships imply that regional mean results are still useful, as long as the interregional variation in their relationship with impact-relevant extreme trends is recognized. These relationships are used to present a clear but rich picture of an aspect of model uncertainty, characterized by the intermodel spread in seasonal precipitation trends, including information from small spatial scales.
Icelandic Coastal Sea Surface Temperature Records Constructed: Putting the Pulse on Air–Sea–Climate Interactions in the Northern North Atlantic. Part I: Comparison with HadISST1 Open-Ocean Surface Temperatures and Preliminary Analysis of Long-Term Patterns and Anomalies of SSTs around Iceland
Authors: Hanna Edward , Jónsson Trausti , Ólafsson Jon , Valdimarsson Hedinn
Published: November 2006

A new comprehensive record of long-term Icelandic sea surface temperature measurements, which have been updated and filled in with reference to air temperature records, is presented. The new SST series reveal important features of the variability of climate in Iceland and the northern North Atlantic. This study documents site histories and possible resulting inconsistencies and biases, for example, changes in observing sites and instruments.

A new 119-yr continuous time series for north Iceland SST is presented, which should prove particularly useful for investigating air–sea ice interactions around northern Iceland. As this is the only part of the country to be regularly engulfed by winter and/or spring sea ice, it is therefore highly sensitive to climatic change. The coastal series correlate well overall with independent Hadley Centre Sea Ice and SST dataset version 1 (HadISST1) series from the adjacent open ocean (mean r = 0.59), although correlations are generally higher in summer than winter and for south and east Iceland compared with the west and north. The seasonal temperature range is generally twice as large at the coastal sites because of differential effects of radiation, melting, mixing, and advection of warmer or colder air or water masses, as well as spatial resolution differences and smoothing in HadISST1.

The long-term climatological averages and graphs for the 10 SST stations and/or their composites reveal decadal variations and trends that are generally similar to Icelandic air temperature records: a cold late-nineteenth-century, rapid warming around the 1920s, an overall warm peak circa 1940, cooling until an “icy” period circa 1970, followed by warming. Regional differences between sites include relatively greater (lesser) long-term variations for the eastern and southern (western and northern) Icelandic coasts, suggesting greater variability and influence of ocean current advection in the southeast. Moreover, Vestmannaeyjar SST data reveal that the late-nineteenth-century cold period in the ocean was not confined to the cold currents off north and east Iceland but also affected the south coast markedly. The Stykkishólmur, Iceland, SST record is relatively noisy and shows very little decadal variation, which may largely be due to fjord ice in cold winters suppressing low temperatures. It is anticipated that researchers may find these Icelandic SST series of practical use as a historic measure of air–sea–climate interactions around Iceland.
Electrofluorescence of dye-tagged sepiolite
Authors: Middleton G. W. , Jennings B. R.
Published: November 2006

In electric fields, anisodiametric mineral particles in suspension orientate and align. When tagged with fluorescent molecules, the alignment is accompanied by changes in the intensities of the polarized components of the emitted fluorescence. By measuring these changes under specific experimental conditions, any non-random directional coincidence of the absorption and emission transition moments associated with the dye molecules can be evaluated and the spatial array of the dyes estimated. From such measurements, the binding of the optical brightening agent FBA1, a triazinylaminostilbene compound, to sepiolite has been studied.
Clays in paleoweathering processes: study of a typical weathering profile in the Hercynian basement in the Montes de Toledo (Spain)
Authors: Vicente M. A. , Molina E. , Espejo R.
Published: November 2006

A series of weathered Paleozoic slates was studied in an area southwest of the Montes de Toledo mountain range where the weathered slates are overlain by a raña formation and show three weathering levels. The fresh slate (at 30 m depth) is composed of ferrous chlorite, mica, quartz and feldspars. In the lowest part of the weathering profile the ferrous chlorite begins to evolve to smectite, and in the intermediate level, all the chlorite has been transformed into smectite. In the upper level (in contact with the raña formation), the smectites evolve to kaolinite, and the micas, which are unaffected at greater depths, begin to evolve to vermiculite, and there has been segregation of the free iron oxyhydroxides producing red, ochre and white zones. Two principal weathering processes, separated in time but superimposed, have been identified.
Diagenetic modification of detrital muscovite: an example from the Great Limestone Cyclothem (Carboniferous) of Co. Durham, UK
Authors: Crowley S. F.
Published: November 2006

Diagenetically modified muscovite grains occur as a frequent component of many Upper Palaeozoic and Mesozoic fluvial-deltaic sandstones and siltstones from Britain and the North Sea. Mineralogical, textural and chemical investigation of examples from the Great Limestone Cyclothem show that such grains consist simply of muscovite and kaolinite. No other sheet-silicate phases are involved. Diagenetic textures indicate that modified grains result from the displacive growth of kaolinite between opened cleavage sheets of detrital muscovite. Fabrics of this type should consequently be termed kaolinite-cemented. In contrast to similar sheet-silicate intergrowths reported from diagenetically altered biotite and chlorite, little or no alteration of muscovite is actually required to account for observed textures.
Octahedral occupancy and the chemical composition of diagenetic (low-temperature) chlorites
Authors: Hillier S. , Velde B.
Published: November 2006

The chemical composition of about 500 diagenetic chlorites, determined by electron microprobe, has been studied in six different sedimentary sequences spanning conditions from early diagenesis to low-grade metamorphism, in the temperature range 40–330°C. The range of Fe/(Fe + Mg) is almost complete and is positively correlated with Al. Five sequences show the same compositional variation. In each, the most siliceous chlorites have the lowest R2+, substantially more octahedral than tetrahedral Al, and the lowest octahedral totals. Conversely, the least siliceous have the highest R2+, nearly equal octahedral and tetrahedral Al, and octahedral totals close to that for an ideal trioctahedral mineral. A dioctahedral substitution Si[]R2−2(where [] represents a vacant octahedral site) which decreases with temperature, describes this variation. Low octahedral totals are, however, induced by the method of calculation and need not indicate vacancies; for published wet chemical analyses of metamorphic chlorites they may simply indicate oxidation of Fe. Intergrown dioctahedral phyllosilicates may partly account for apparent vacancies in diagenetic chlorites. Nevertheless, the correlation of composition with temperature and similarities to the temperature-related evolution of synthetic chlorites, suggest that diagenetic chlorites are compositionally distinct from, but metastable with respect to, fully trioctahedral metamorphic chlorites. Temperature-related trends are modified by bulk composition, complicating their potential use for low-temperature geothermometry.
Relationships between authigenic mineral transformation and variation in vitrinite reflectance during diagenesis: an example from the Tertiary of northern Kyushu, Japan
Authors: Miki T. , Nakamuta Y. , Aizawa J.
Published: November 2006

The Tertiary sequences in northern Kyushu, Japan, contain several types of zeolite and clay minerals together with carbonaceous materials. A correlation between authigenic mineral zones and vitrinite reflectance reveals the delay in mineral authigenesis relative to the increase in vitrinite reflectance compared with similar studies in other regions. This may be ascribed to causes such as high paleogeothermal gradient, and chemical composition of pore-waters and host sediment.
K-Ar dating of authigenic illite-smectite clay material: application to complex mixtures of mixed-layer assemblages
Authors: Mossmann J.-R.
Published: November 2006

Genetically homogeneous clay fractions are not always available for K-Ar isotopic dating of authigenic sedimentary material, particularly when dating illitic mixed-layer clay minerals. Three populations of mixed-layer clay minerals have been recognized in Upper Triassic sandstones from the Paris Basin (France), their occurrences being related to the flow of allochthonous fluids across the stratigraphic sections of the basin during Mesozoic times. A method is described for interpreting the K-Ar mixture ages obtained on carefully selected fractions, resulting in constraints being able to be made on the timing of the movements of these fluids.
Clay minerals as indicators of diagenetic and anchimetamorphic grade in an overthrust belt, External Domain of southern Canadian Appalachians
Authors: Yang C. , Hesse R.
Published: November 2006

Lower Palaeozoic shales and slates in the External Domain of the southern Canadian Appalachians are composed predominantly of illite and chlorite with minor occurrences of I-S mixed-layer minerals (restricted to samples with illite crystallinity, IC > 0·62°Δ2Θ) and paragonite (restricted to samples with IC < 0·42°Δ2Θ). Inverted diagenesis has occurred in the NW part of the Chaudière Nappe, indicating pre-orogenic deep burial diagenesis at the original depositional site, whereas to the SE, the diagenetic pattern was affected by synorogenic heating. Within the east-dipping thrust-fold belt and the St Lawrence Lowlands, increasing grade towards the S suggests a gradual southward increase in post-tectonic burial depth. Narrow (3–5 km) thermal haloes around the Cretaceous Monteregian intrusions show limited effects on the country rocks.

The percentage of 2M1 mica polytypes and bo increase with decreasing IC. Chlorite crystallinity (CC) increases with increasing IC. Good correlations between IC, %2M1, CC and bo of micas indicate that these parameters are reliable monitors of high-grade diagenesis and low-grade metamorphism in clay-rich sedimentary rocks. IC and CC improve with increasing grain size, illustrating the effect of grain size on IC and CC. Organic material affects IC more strongly in strata with lower permeability than in those with higher permeability. In the diagenetic zone, glycolation does not uniformly produce a narrowing of the 10 Å illite peak, but may also broaden it by up to 15%, probably due to the presence of Kalkberg-type mixed-layers.
Disorder induced by de-intercalation of DMSO from kaolinite
Authors: Heller-Kallai L. , Huard E. , Prost R.
Published: November 2006

De-intercalation of DMSO from well-crystallised kaolinites induced disorder. SEM, XRD and low-temperature IR were used to probe changes in morphology, layer stacking, and the environment of OH groups, respectively. The degree and type of disorder depended on the starting material and on the method of removing the intercalate. Rapid removal by heating at 250°C caused smaller changes than more prolonged heating at lower temperature, or washing with water.
Influence of potassium concentration on the swelling and compaction of mixed (Na,K) ion-exchanged montmorillonite
Authors: Denis J. H. , Keall M. J. , Hall P. L. , Meeten G. H.
Published: November 2006

Oedometer swelling and compaction tests up to a maximum pressure of 32 bars were made on the Wyoming montmorillonite SWy-1 with a range of mixed (Na,K) exchange ion compositions. The permeabilities and water diffusivities of the compacted clays were calculated using soil physics theory. Significant inhibition of swelling from that of the Na-montmorillonite is developed for K fractions in the range 0·30 < K+ < 0·56. However, the water diffusivity increases by a factor of approximately six as the K exchange fraction increases from 0 to 0·7. Permeabilities to water flow show a power-law dependence on the void ratio e.

XRD measurements at controlled humidity yield equilibrium interlayer spacings which in general increase with both increasing relative humidity and increasing Na exchange fraction. The extent of swelling is strongly inhibited in clays having Na exchange fractions of 0·44 or less, in good agreement with the oedometer studies.
Amorphous hydroxyaluminium silicates formed under physiological saline conditions, and in CaCo3-buffered solutions. Stability and significance for Alzheimer plaque precipitates
Authors: Farmer V. C. , Palmieri F. , Violante A. , Violante P.
Published: November 2006

In an attempt to determine the nature and conditions of formation of the aluminium silicate precipitates present at the core of senile plaque in the brains of patients with Alzheimer's disease, aluminosilicate precipitates have been prepared and equilibrated for up to one year in physiological saline conditions at 40°C and a pH near 7·4. The structure and composition of these precipitates, and the associated concentrations of free silicic acid, were similar to those found in systems buffered with CaCO3at 20–25°C. Imogolite-like products with Si : Al ratios near 0·5 were obtained at silicic acid concentrations <100µm, and hydrous feldspathoid products with ratios ≥1·0 became dominant at silicic acid concentrations greater than ∼150µm. These products do not match senile plaque precipitates, which have Si : Al ratios ≥1·0, but form in an environment with <100µmSi. The relative stability of aluminium hydroxides, proto-imogolite allophane and hydrous feldspathoids are estimated from equilibrated silicic acid concentrations.
Kerolite-stevensite mixed-layers from the Madrid Basin, Central Spain
Authors: Martin de Vidales J. L. , Pozo M. , Alia J. M. , Garcia-Navarro F. , Rull F.
Published: November 2006

Structural features of very highly disordered 2:1 trioctahedral phyllosilicates from the Madrid Basin have been studied. Application of Fourier methods to XRD patterns shows that these materials consist of random kerolite-stevensite mixed-layered phases (R = 0) with 50–80% kerolite layers, and have a very small particle size with a mean of three unit-cells stacked in the c* direction. IR spectrum deconvolution in OH-stretching and librational modes seems to indicate five different types of water. Specific surface measurements (N2, BET) indicate anomalous high values (240–320 m2/g). These results suggest important catalytic and surface chemistry applications.
A Kaolin-smectite interstratification sequence from a red and black complex
Authors: Bühmann C. , Grubb P. L. C.
Published: November 2006

The sequential development of kaolin by progressive alteration of smectite, involving kaolin-smectite interstratifications as a genetic link is described from a red and black complex. Mineral compositions were studied using XRD, DTA and XRF techniques. The basalt-derived soils are situated along a 600 m transect and grade in colour from dark grey (10 YR 3/1) to red (5 YR 3/3). The kaolin proportions in the interstratification increase almost linearly with increasing reddening up to ∼80%. Whole-soil chemical analyses exhibit no significant variations in the major element composition, but dithionite extractable Fe increases along the transect from 1% to 4·16%. Hematite and goethite are the only secondary iron phases. Topographic differences are slight but sub-surface bedrock contours plus appreciable variations in sand content between red and black soils could be genetically significant.
Pressure-induced cation exchange in bentonite/laponite mixtures
Authors: Paterson E. , Clark D. R.
Published: November 2006

Exchangeable cation associations in physical mixtures of bentonite and laponite have been examined using X-ray diffraction and a combination of electron microprobe analysis and multivariate statistical methods. The results suggest that cation exchange can occur in air-dry mixtures when pressure (∼64 kbar) is applied. Although no attempt is made to describe the mechanism of the reaction it appears to require the presence of adsorbed water.
The chemical composition and structure of a 14 Å intergradient mineral in a Korean Ultisol
Authors: Wada K. , Kakuto Y. , Wilson M. A. , Hanna J. V.
Published: November 2006

An intergradient 14 Å mineral showing X-ray diffraction features of “chloritized” vermiculite in a Korean Ultisol was studied. The structural formula of the whole 2:1 layer-silicate (14 Å mineral and mica) in the Na+-saturated 0·2–0·5 µm fraction was obtained by elemental, thermogravimetric and 29Si and 27Al nuclear magnetic resonance spectroscopic analyses in combination with extraction of the interlayer material from the 14 Å mineral by hot 1/3 m sodium citrate treatment. This formula showed: (1) the 2 : 1 layer contains nearly one Al3+ in four tetrahedral positions, and Al3+ is the dominant cation in the octahedral sheet; (2) K+, exchangeable Na+ and sodium citrate extractable 1 : 1 layer occupy the interlayer space of the 14 Å mineral in similar proportions. Very little interlayer K was replaced by Na+ during the citrate treatment. Possible schemes of alteration of the 2 : 1 layer to the 1 : 1 layer as its interlayer material are discussed.
Thermal analysis of pyridine-treated sepiolite and palygorskite
Authors: Shuali U. , Yariv S. , Steinberg M. , Müller-Vonmoos M. , Kahr G. , Rub A.
Published: November 2006

The thermal behaviour of sepiolite and palygorskite treated with pyridine (Py) was investigated by DTA, TG, DTG and EGA (by MS) under a flow of air and inert gases (N2 or Ar). The thermal analysis showed that the organic base was adsorbed by the clays, penetrating into the clay pores and replacing zeolitic and bound water. Its presence in the pores shifted the dehydroxylation peak to temperatures higher than the corresponding peak in the untreated clays. Under N2 and Ar, thermal desorption of Py from sepiolite was observed at 260 and 650°C whereas for palygorskite only traces of Py were detected in the evolved gases. In addition to desorption, reactions of pyrolysis and condensation to coke were detected by the evolution of ammonia, methane and hydrogen, respectively. In air, oxidation of the organic matter led to the appearance of exothermic peaks. The profile of the DTA curve and the temperatures of the most intense exothermic peaks were determined by the rate of the carbon oxidation.
Formation of synthetic analogues of double metal-hydroxy carbonate minerals under controlled pH conditions: II. The synthesis of desautelsite
Authors: Hansen H. C. B. , Taylor R. M.
Published: November 2006

Desautelsite, a Mg(II)Mn(III) hydroxy carbonate first described in 1979 and represented by the general formula Mg(8−x)Mn(III)x(OH)16(CO3)x/2(in which 2 <x< 2·67), has been synthesized under controlled pH conditions (induced hydrolysis) and coprecipitation techniques. In the pH-stat syntheses, the desautelsite is formed by aerial oxidation of MnCO3in 0·05–0·15mMg(NO3)2solutions at ∼pH 9 and temperatures of 35°C where, in the absence of Mg, manganite would normally form. The synthesis product from this technique is generally more crystalline than that formed by the coprecipitation method. Composition, particle shape and aggregation may be controlled through variations of the Mg concentration, pH, aeration rate or temperature. Indirect evidence suggests Mn to be present in the +3 oxidation state in the desautelsite.
Ultra Microanalysis of Ferric Ion Using Triazene and Capillary Electrophoresis
Authors: Nishiwaki Keiji , Taga Atsushi , Yamaya Masako , Morita Yusuke , Suzuki Yukiko , Honda Susumu , Matsuo Keizo
Published: November 2006

The triazene compound {2,2′-[3-(4-methoxyphenyl)triaz-2-ene-1,1-diyl]diethanol} was utilized for the high sensitive and quantitative detection of ferric ion.
Electrically Detected Magnetic Resonance (EDMR) Measurements of Bulk Silicon Carbide (SiC) Crystals
Authors: Sato Toshiyuki , Yokoyama Hidekatsu , Ohya Hiroaki
Published: November 2006

Electrically detected magnetic resonance (EDMR) measurements of bulk silicon carbide (SiC) crystals, which have wide band-gaps, were conducted. A high-power ultraviolet light-emitting diode was used as a low-noise light source to excite excessive carriers. Under light irradiation, EDMR spectra of a 4H–SiC wafer (8-mm wide, 8-mm long) at an ESR frequency of 900 MHz was obtained with a g-value of 2.000 ± 0.003, indicating that the major recombination center was a vacancy. EDMR spectra were observed at all detection phases of magnetic field modulation. The spectrum observed at in-phase (0 degrees) was a single line; at out-of-phase (90 degrees), the different spectrum was observed.
Pirates of the Salish Sea: Labor, Mobility, and Environment in the Transnational West
Authors: WADEWITZ LISSA
Published: November 2006

This article illustrates that a transnational perspective reveals how nature and work intertwined to shape workers' responses to evolving regional class relations in the western Canadian-U.S. borderlands. Labor and environment are intimately connected in all the West's extractive industries, and workers engaged and learned about the natural world through their labor. In the watery borderland between Washington and British Columbia, they also used the fl uidity of this border to cross the international line and enter more advantageous markets, escape authorities, and express dissatisfaction with class inequities and ethnoracial tensions. These activities earned them the epithets "bandits" and "pirates," especially from U.S. and Canadian canners who sought to manipulate ethnic differences to exploit workers more effectively. The Fraser River salmon fi shery offers a microcosm through which to assess how western labor and environmental history intersect, and what these linkages can reveal about issues of power and human agency.
Loyalty Questioned: Nuevomexicanos in the Great War
Authors: GONZALES PHILLIP , MASSMANN ANN
Published: November 2006

Over four years after oil companies first applied for a permit, Congress authorized the Alaska Oil Pipeline in November 1973. Running from the Arctic Ocean to the Pacific,the pipeline crossed 600 miles of federal land, which made it a "major action significantly affecting the environment," thus triggering an environmental impact statement under the National Environmental Policy Act of 1969 (NEPA). Standard accounts tell of revolutionary environmental laws running into the economic reality of the 1970s. What has been lost in the telling is that the pipeline approval offered Congress an opportunity to investigate the wisdom of a proposed internal improvement. The pipeline controversy was not just the first battle of the environmental decade. It also continued nearly two centuries of debate over internal improvements, public financing of private investments, federal incorporation, monopoly charters, and national security. The pipeline approval was as much a decision about political economy as it was an environmental policy decision.
Asymptotic analysis of the Askey-scheme I: from Krawtchouk to Charlier
Authors: Dominici Diego
Published: November 2006

We analyze the Charlier polynomials C
n(χ) and their zeros asymptotically as n → ∞. We obtain asymptotic approximations, using the limit relation between the Krawtchouk and Charlier polynomials, involving some special functions. We give numerical examples showing the accuracy of our formulas.
Comparison of serological and clinical findings in Turkish patients with cystic echinococcosis
Authors: Yolasigmaz A. , Reiterová K. , Turk M. , Reyhan E. , Bozdag A. , Karababa A. , Altintas Nuray , Altintas Nasmiye
Published: November 2006

Cystic echinococcosis (CE), caused by the cestode Echinococcus granulosus, is potentially dangerous for humans. The aim of this study was to examine serological and clinical findings regarding cysts localisation and individual responses in 54 patients with CE. The majority of patients in this study were females (63 %) and the average age was 46.3 years. Most of the patients lived in rural areas or kept a dog (46 %) for a long time. The most frequent symptoms were hypochondrial pain (48.9 %), epigastrial discomfort (27.7 %), vomiting (21.3 %), minor cough (12.8 %), urticaria (6.3 %), weakness (4.3 %), fever (2.1 %), side-or back-ache (4.3 %). However, 17 % of the patients showed no symptoms. In every case, the ultrasound (USG) and/or computer tomography (CT) investigations were positive. In most cases (53.2 % of the patients) a single cyst was found but 46.8 % of the patients had multiple cyst formations (from 2 to 9 cysts) located in the liver. Sporadic lung, splenetic, mesenterial, tibial and cerebral localisations were also found. The patients were individually treated with albendazol (10–15 mg/kg) five days prior and six months after the surgical treatment. Serum samples were investigated by the serological techniques: IHAT, ELISA and Western blot using hydatid fluid antigen. In the patient sera, the specific antibody levels were mostly increased after surgery. Different results were obtained only in two patients. In the first case, seroconversion was delayed. In the other case all ELISA results were negative, however, the Western blot analysis and surgery proved the presence of CE. The results suggest that the different antibody response of patients depends on the individual immune response. Multiple localization and various stages of CE cysts demonstrate the necessity of a complex approach for the confirmation of a correct diagnosis.
Effect of Immobilized Nerve Growth Factor on Conductive Polymers: Electrical Properties and Cellular Response
Authors: Kim D.‐H. , Richardson‐Burns S. M. , Hendricks J. L. , Sequera C. , Martin D. C.
Published: November 2006

The use of biologically active dopants in conductive polymers allows the polymer to be tailored for specific applications. The incorporation of nerve growth factor (NGF) as a co‐dopant in the electrochemical deposition of conductive polymers is evaluated for its ability to elicit specific biological interactions with neurons. The electrochemical properties of the NGF‐modified conducting polymers are studied by impedance spectroscopy and cyclic voltammetry. Impedance measurements at the neurobiologically important frequency of 1 kHz reveal that the minimum impedance of the NGF‐modified polypyrrole (PPy) film, 15 kΩ, is lower than the minimum impedance of peptide‐modified PPy film (360 kΩ). Similar results are found with NGF‐modified poly(3,4‐ethylene dioxythiophene) (PEDOT). The microstructure of the conductive polymer films is characterized by optical microscopy and electron microscopy and indicates that the NGF‐functionalized polymer surface topology is similar to that of the unmodified polymer film. Optical and fluorescence microscopy reveal that PC‐12 (rat pheochromacytoma) cells adhered to the NGF‐modified substrate and extended neurites on both PPy and PEDOT, indicating that the NGF in the polymer film is biologically active. Taken together these data indicate that the incorporation of NGF can modify the biological interactions of the electrode without compromising the conductive properties or the morphology of the polymeric film.
Imatinib mesylate induces hypophosphatemia in patients with chronic myeloid leukemia in late chronic phase, and this effect is associated with response
Authors: Osorio S. , Noblejas A. García , Durán A. , Steegmann J.L.
Published: November 2006

Imatinib is the drug of first choice for most patients with chronic phase chronic myeloid leukemia (CML). Although it is generally well tolerated, a number of hematological and nonhematological side‐effects have been described. We report here that imatinib induces hypophosphatemia in a high proportion of our series of CML patients previously treated with interferon α, and that this previously unreported side effect is associated with response. Am. J. Hematol., 2007. © 2006 Wiley‐Liss, Inc.
Chirale Ferrocenliganden in der asymmetrischen Katalyse
Authors: Gómez Arrayás Ramón , Adrio Javier , Carretero Juan Carlos
Published: November 2006

Trotz schon beeindruckender Fortschritte im Bereich der asymmetrischen Katalyse während der letzten zehn Jahre hält die Nachfrage nach neuen Katalysatoren, Liganden und Anwendungen zur Entwicklung neuer Reaktionen und zur Verbesserung vorliegender Prozesse an. Wegen ihrer breiten Verfügbarkeit, besonderen stereochemischen Eigenschaften und der Möglichkeit, die sterischen und elektronischen Eigenschaften exakt abzustimmen, bilden Ferrocenliganden eine der vielseitigsten Ligandenklassen für die asymmetrische Katalyse. Ferrocenkatalysatoren wurden in zahlreichen enantioselektiven Prozessen unterschiedlichster Art eingesetzt, und dieser Aufsatz diskutiert die Fortschritte der letzten Jahre. Ein besonderer Schwerpunkt liegt auf der Diskussion bahnbrechender asymmetrischer Prozesse und der Entwicklung neuer, effizienter Typen von Ferrocenliganden.
Recent Applications of Chiral Ferrocene Ligands in Asymmetric Catalysis
Authors: Gómez Arrayás Ramón , Adrio Javier , Carretero Juan Carlos
Published: November 2006

Despite the impressive progress achieved in asymmetric catalysis during the last decade, an increasing number of new catalysts, ligands, and applications are reported every year to satisfy the need to embrace a wider range of reactions and to improve the efficiency of existing processes. Because of their availability, unique stereochemical aspects, and wide variety of coordination modes and possibilities for the fine‐tuning of the steric and electronic properties, ferrocene‐based ligands constitute one of the most versatile ligand architectures in the current scenario of asymmetric catalysis. Over the last few years ferrocene catalysts have been successfully applied in an amazing variety of enantioselective processes. This Review documents these recent advances, with special emphasis on the most innovative asymmetric processes and the development of novel, efficient types of ferrocene ligands.
A hybrid active–passive fault‐tolerant control approach
Authors: Su Steven W. , Bao Jie , Lee Peter L.
Published: November 2006

This paper presents a hybrid active–passive approach to fault‐tolerant control (FTC). It combines the existing active fault‐tolerant control techniques with the newly developed passive decentralized unconditionally stabilizing (DUS) control. The FTC system is developed to achieve optimized performance under sensor failures that are most frequently encountered and/or have significant impact on the process, while guaranteeing the stability under any other failures. This approach can significantly reduce the level of complexity of FTC systems, leading to cost‐effective designs. A stability condition for control systems based on reconstructed virtual sensor outputs is developed. The effectiveness of the proposed method is illustrated by control of a distillation column. Copyright © 2006 Curtin University of Technology and John Wiley & Sons, Ltd.
Control of unstable processes with two RHP poles, a zero and time delay
Authors: Rao A. Seshagiri , Chidambaram M.
Published: November 2006

A lead or lag compensator in series with a proportional‐integral‐derivative (PID) controller is designed for unstable processes with two unstable poles and a zero with time delay. Such transfer functions arise in modeling an isothermal continuous stirred tank reactor (CSTR) carrying out autocatalytic reactions, in crystallizers and in nonisothermal CSTRs. The direct synthesis method is used for the design of the controller. The desired closed‐loop transfer function is specified to get the required PID controller with lead/lag compensator. Simulation studies are given to show the effectiveness of the proposed method. For systems with and without negative zero, significant improvement is obtained when compared to the method proposed by Lee et al., (Chem. Eng. Sci. 2000; 55: 3481–3493). Copyright © 2006 Curtin University of Technology and John Wiley & Sons, Ltd.
Shape‐Dependent Catalytic Activity of Silver Nanoparticles for the Oxidation of Styrene
Authors: Xu Run , Wang Dingsheng , Zhang Jiatao , Li Yadong
Published: November 2006

Metal nanoparticles with different shapes have different crystallographic faces. It is therefore of interest to study the effect of the shape of metal nanoparticles on their catalytic activity in various organic and inorganic reactions. Truncated triangular silver nanoplates with well‐defined planes were synthesized by a simple solvothermal approach. The activity of these truncated triangular silver nanoparticles was compared with that of cubic and near‐spherical silver nanoparticles in the oxidation of styrene in colloidal solution. It was found that the crystal faces of silver nanoparticles play an essential role in determining the catalytic oxidation properties. The silver nanocubes had the {100} crystal faces as the basal plane, whereas truncated triangular nanoplates and near‐spherical nanoparticles predominantly exposed the most‐stable {111} crystal faces. As a result, the rate of the reaction over the nanocubes was more than 14 times higher than that on nanoplates and four times higher than that on near‐spherical nanoparticles.
Impact of renal dysfunction on operative mortality following endovascular abdominal aortic aneurysm surgery
Authors: van Eps R G Statius , Leurs L J , Hobo R , Harris P L , Buth J
Published: November 2006

Background

Preoperative renal dysfunction is a significant risk factor for death after open abdominal aortic aneurysm repair. The aim of this study was to determine whether renal dysfunction also affected mortality after endovascular aneurysm repair.

Methods

Patients from the EUROSTAR registry were stratified into two groups: 4198 with normal renal function (creatinine less than 133 µmol/ml) and 969 with renal dysfunction (serum creatinine more than 133 µmol/ml). Patient characteristics and postoperative complications in the two groups were compared and the effect of renal dysfunction on operative mortality was analysed by multivariable regression models.

Results

Patients with renal dysfunction had significantly more co-morbidities, including cardiac and pulmonary impairment. Thirty-day mortality was significantly higher in the group with renal dysfunction (6·2 versus 2·0 per cent; P < 0·001). A significant increase in mortality (5·5 per cent) was also seen in patients with moderate renal dysfunction (serum creatinine 133–265 µmol/ml). After adjustment for age and other risk factors, renal dysfunction was still an independent risk factor for 30-day mortality (odds ratio 2·3, 95 per cent confidence interval 1·6 to 3·3; P < 0·001).

Conclusion

Renal dysfunction was a significant and independent risk factor for death after endovascular aneurysm repair.
Complex Biohopanoids Synthesis: Efficient Anchoring of Ribosyl Subunits onto a C30 Hopane
Authors: Pan Weidong , Sun Chao , Zhang Yongmin , Liang Guangyi , Sinaÿ Pierre , Vincent Stéphane P.
Published: November 2006

Bacteriohopanoids represent a particularly important series of triterpenoids, widely distributed in bacteria. One of the common features of these pentacyclic hopanepolyols is the presence of an extended non‐terpenoid and polyhydroxylated side chain attached to the triterpenic moiety through a CC bond. The biological function of biohopanoids also has to be addressed when one considers the broad diversity in both structures and functionalities found in the side chain. Moreover, the stereochemistries of some biohopanoids are still unconfirmed, due to the lack of synthetic methods to prepare them. In this study we describe an efficient methodology for the formation of the CC bond between the C30‐hopane component and C5‐polyhydroxylated carbohydrates through the use of a hopanyllithium intermediate, which has enabled us to synthesize several biohopanoid derivatives. We also report the first synthesis of hopanepentol bearing an additional hydroxy group at position C31.
Synthesis and Characterisation of Nonclassical Ruthenium Hydride Complexes Containing Chelating Bidentate and Tridentate Phosphine Ligands
Authors: Prechtl Martin H. G. , Ben‐David Yehoshoa , Giunta Daniela , Busch Stefan , Taniguchi Yuki , Wisniewski Wolfgang , Görls Helmar , Mynott Richard J. , Theyssen Nils , Milstein David , Leitner Walter
Published: November 2006

The synthesis and characterisation of nonclassical ruthenium hydride complexes containing bidentate PP and tridentate PCP and PNP pincer‐type ligands are described. The mononuclear and dinuclear ruthenium complexes presented have been synthesised in moderate to high yields by the direct hydrogenation route (one‐pot synthesis) or in a two‐step procedure. In both cases [Ru(cod)(metallyl)2] served as a readily available precursor. The influences of the coordination geometry and the ligand framework on the structure, binding, and chemical properties of the MH2 fragments were studied by X‐ray crystal structure analysis, spectroscopic methods, and reactivity towards N2, D2, and deuterated solvents.
Catalytic Applications of Metal Nanoparticles in Imidazolium Ionic Liquids
Authors: Migowski Pedro , Dupont Jaïrton
Published: November 2006

Metal nanoparticles (MNPs) with a small diameter and narrow size distribution can be prepared by H2 reduction of metal compounds or decomposition of organometallic species dissolved in ionic liquids (ILs). MNPs dispersed in ILs are catalysts for reactions under multiphase conditions. These soluble MNPs possess a pronounced surfacelike rather than single‐site like catalytic properties. In other cases the MNPs are not stable and tend to aggregate or serve as reservoirs of mononuclear catalytically active species.
Asymmetric catalysis of Morita‐Baylis‐Hillman reactions by chiral phosphine Lewis bases bearing multiple phenol groups
Authors: Shi Min , Liu Ying‐Hao , Chen Lian‐Hui
Published: November 2006

In the Morita‐Baylis‐Hillman (MBH) reactions of arylaldehydes with methyl vinyl ketone, it was observed that in the presence of a catalytic amount of a chiral phosphine Lewis base (CPLB) bearing multiple phenol groups, such as CPLB1 (10 mol %), the corresponding MBH adducts could be obtained in moderate to good yields with low to moderate ee's (4–45% ee) at ambient temperature (10°C) in THF. Chirality, 2007. © 2006 Wiley‐Liss, Inc.
Stereoselective degradation kinetics of tebuconazole in rabbits
Authors: Zhu Wentao , Qiu Jing , Dang Ziheng , Lv Chunguang , Jia Guifang , Li Li , Zhou Zhiqiang
Published: November 2006

Tebuconazole[(RS)‐1‐p‐chlorophenyl‐4,4‐dimethyl‐3‐(1H‐1,2,4‐triazol‐1‐ylmethyl)pentan‐3‐ol] is a potent triazole fungicide and consists of a pair of enantiomers. The enantioselective degradation kinetics of tebuconazole was investigated in rabbits by intravenous (iv) injection. The concentrations of (−)‐(R)‐tebuconazole and (+)‐(S)‐tebuconazole in plasma and tissues were determined by HPLC with a cellulose tris(3,5‐dimethylphenylcarbamate)‐based chiral stationary phase. Enantioselective analysis methods for this fungicide in plasma and tissues were developed and validated. Good linearities were obtained over the concentration range of 0.25–25 mg/l for both enantiomers. The degradation followed pseudo‐first‐order kinetics and the degradation of the (+)‐(S)‐tebuconazole was much faster than that of the (−)‐(R)‐tebuconazole in plasma after administration of racemic tebuconazole. This study also indicated that environmental assessment of enantiomeric degradation may be needed to fully evaluate risks of tebuconazole use. Chirality, 2007. © 2006 Wiley‐Liss, Inc.
Untersuchung des Adsorptionsverhaltens von Dünnschichtfiltern am Beispiel der Kfz‐Innenraumfilter
Authors: Zhang P. , Sager U. , Schmidt F. , Wanko H. , Ulrich J.
Published: November 2006

Kfz‐Innenraumfilter schützen Fahrzeuginsassen vor Partikeln und Schadgasen der Außenluft. Die adsorptive Abscheidung der Schadgase an dünnen Aktivkohleschichten wird erheblich beeinflusst durch die Umgebungsbedingungen Temperatur und relative Luftfeuchte, die starken Schwankungen im Tages‐ und Jahresgang unterliegen. Ziel der Untersuchungen war, die Abhängigkeit der Abscheideleistung für diese Parameter aufzuzeigen und die dynamischen Adsorptionsvorgänge theoretisch zu beschreiben. Diese Kenntnisse können zu einer besseren Nutzung des Filterpotenzials führen und Hinweise für die Gestaltung einer möglichen Regeneration liefern.
Untersuchungen zur Staubungsneigung von Braunkohle unterschiedlicher Feuchte
Authors: Reznik G. , Klenk U. , Schmidt E.
Published: November 2006

Der Umgang mit Schüttgütern setzt in den meisten Fällen feinen Staub frei. Zur Untersuchung dieses Staubungsverhaltens können Rotationsverfahren, welche die kontinuierliche mechanische Belastung eines Schüttgutes simulieren, oder Fallverfahren, mit denen die Aufwirbelung von Staub beim einmaligen Auftreffen des abgeworfenen Materials auf eine feste Oberfläche wiedergegeben wird, eingesetzt werden. Dabei spielt neben den materialspezifischen Eigenschaften auch die Feuchte der Proben eine große Rolle bei der Entstehung von Staub. Dieser Zusammenhang zwischen Staubentstehung und Probenfeuchte wurde am Beispiel zweier verschiedener Braunkohlequalitäten genauer betrachtet.
Adsorptionsmessungen von n‐Alkanen am 5A‐Zeolith
Authors: Möller A. , Yang X. , Caro J. , Staudt R.
Published: November 2006

Die Dimensionierung und das Management industrieller Anlagen für die adsorptive Trennung von Kohlenwasserstoffgemischen und für die Katalyse setzen eine zuverlässige Kenntnis thermodynamischer und kinetischer Stoffparameter der einzusetzenden Adsorbentien voraus. Mit Hilfe gravimetrischer Sorptionsmessungen werden Adsorptionsisothermen für verschiedene n‐Alkane am 5A‐Zeolith gemessen.
A Taylor–Galerkin approach for modelling a spherically symmetric advective–dispersive transport problem
Authors: Dong Wenjun , Selvadurai A. P. S.
Published: November 2006

This paper presents a numerical approach for examining a spherically symmetric advective–dispersive contaminant transport problem. The Taylor–Galerkin method that is based on an Euler time‐integration scheme is used to solve the governing transport equation. A Fourier analysis shows that the Taylor–Galerkin method with a forward Euler time integration can generate an oscillation‐free and non‐diffusive solution for the pure advection equation when the Courant number satisfies the constraint Cr = 1. Such numerical advantages, however, do not extend to the advection–dispersion equation. Based on these observations, an operator‐splitting Euler‐integration‐based Taylor–Galerkin scheme is developed to model the advection‐dominated transport process for a problem that exhibits spherical symmetry. The spherically symmetric transport problem is solved using this approach and a conversion to a one‐dimensional linear space with an associated co‐ordinate transformation. Copyright © 2006 John Wiley & Sons, Ltd.
Propagation of longest‐edge mesh patterns in local adaptive refinement
Authors: Suárez J. P. , Plaza A. , Carey G. F.
Published: November 2006

We examine the propagation of local adaptive mesh refinement (AMR) under a longest edge conformity scheme. Supporting numerical studies are included and discussed. Of specific interest is the statistical behaviour of the propagation zone in AMR of simplicial meshes. To this end three propagation metrics are used: the total number of original triangles in the propagation paths emanating from any target element, the longest individual edge path, and the extent of secondary refinement due to the conformity. Copyright © 2006 John Wiley & Sons, Ltd.
Dynamically equivalent implicit algorithms for the integration of rigid body rotations
Authors: Krysl P.
Published: November 2006

Two midpoint‐trapezoid pairs of dynamically equivalent (conjugate) algorithms are derived as compositions of first‐order forward Euler and backward Euler integrators as applied to an incremental form of the initial‐value problem of three‐dimensional rigid body rotation. The algorithms are related to the recently developed methodology of the so‐called Munthe‐Kaas Runge–Kutta methods. Selected examples are used to illustrate the excellent long‐term integration properties. Copyright © 2006 John Wiley & Sons, Ltd.
Performance of optimum wavelet for DS‐CDMA chip waveform over multi‐path Rayleigh fading channels
Authors: Öztürk Ertan , Şahin Barış
Published: November 2006

In this paper, the probability of error (Pe) expression of asynchronous direct sequence‐code division multiple access (DS‐CDMA) signals using band‐limited chip waveforms is derived over multi‐path Rayleigh fading channels. In receiver, a matched filter‐based rake receiver in conjunction with maximum ratio combiner (MRC) is considered. Numerical values for thePeare calculated for various chip waveforms including an optimum wavelet waveform. Analytical results are verified by conducting simulations. Results show that the optimum wavelet‐based scheme outperforms time‐limited raised cosine, half sine, rectangular and band‐limited square‐root raised cosine chip waveform‐based schemes in terms of thePeand the capacity defined as the number of users per Hertz for a samePelevel. Copyright © 2006 John Wiley & Sons, Ltd.