bluuebunny/crossref_metadata_2025 huggingface dataset:
Ice sheet erosion patterns in valley systems in northern Sweden investigated using cosmogenic nuclides
Authors: Li Yingkui , Harbor Jon , Stroeven Arjen P. , Fabel Derek , Kleman Johan , Fink David , Caffee Marc , Elmore David
Published: August 2005

Erosion patterns associated with glaciation of trunk and hanging valley systems in northern Sweden were investigated using cosmogenic nuclide 10Be apparent exposure ages and inferred nuclide inheritance. Sequences of samples taken across valleys known to have been covered repeatedly by the Fennoscandian ice sheet revealed two primary patterns of erosion. In Vávlávágge the exposure age pattern is consistent with >2 m of glacial erosion during the last glacial cycle along the entire profile. At Rávtasvággi, Dievssavággi and Alisvággi, exposure ages in the valley bottom contrast with apparent exposure ages two to four times older on the valley sides. The older ages on the valley sides reflect cosmogenic nuclide inheritance due to limited (<2 m) bedrock erosion of the valley sides during the last glacial cycle. The pattern and scale of erosion in these valleys indicates that glacial valley formation is a result of multiple glacial cycles rather than the result of topographic modification during a single glacial cycle. Initial data comparing hanging valley and trunk valley sites do not show distinct differences in apparent exposure ages. Slightly older ages for samples from hanging valley bottoms may suggest nuclide inheritance indicating lower erosion than in trunk valley bottoms, as would be expected given the marked topographic step between hanging and trunk valleys. Although quantifying the amount of erosion depends on the assumed cosmogenic nuclide inheritance prior to the onset of erosion, the pattern of erosion is independent of this. Hence the observed pattern of cosmogenic nuclide concentrations provides constraints on spatial patterns of erosion and helps to refine understanding of the timing and extent of landform modification by glaciation. Copyright © 2005 John Wiley & Sons, Ltd.
Dating floodplain sediments using tree‐ring response to burial
Authors: Friedman Jonathan M. , Vincent Kirk R. , Shafroth Patrick B.
Published: August 2005

Floodplain sediments can be dated precisely based on the change in anatomy of tree rings upon burial. When a stem of tamarisk (Tamarix ramosissima) or sandbar willow (Salix exigua) is buried, subsequent annual rings in the buried section resemble the rings of roots: rings become narrower, vessels within the rings become larger, and transitions between rings become less distinct. We combined observations of these changes with tree‐ring counts to determine the year of deposition of sedimentary beds exposed in a 150‐m‐long trench across the floodplain of the Rio Puerco, a rapidly filling arroyo in New Mexico. This method reliably dated most beds thicker than about 30 cm to within a year of deposition. Floodplain aggradation rates varied dramatically through time and space. Sediment deposition was mostly limited to brief overbank flows occurring every few years. The most rapid deposition occurred on channel‐margin levees, which migrated laterally during channel narrowing. At the decadal timescale, the cross‐section‐average sediment deposition rate was steady, but there was a shift in the spatial pattern of deposition in the 1980s. From 1936 to 1986, sediment deposition occurred by channel narrowing, with little change in elevation of the thalweg. After 1986 sediment deposition occurred by vertical aggradation. From 1936 to 2000 about 27 per cent of the arroyo cross‐section filled with sediment. The rate of filling from 1962 to 2000 was 0·8 vertical m/decade or 85 m2/decade. Published in 2005 by John Wiley & Sons, Ltd.
Contribution of deep‐seated bedrock landslides to erosion of a glaciated basin in southern Alaska
Authors: Arsenault Ann M. , Meigs Andrew J.
Published: August 2005

Landslides represent a key component of catchment‐scale denudation, though their relative contribution to the erosion of glaciated basins is not well known. Bedrock landslide contribution was investigated on the surface of one of eleven glaciers on a glaciated ridge in the Chugach‐St Elias Range of southern Alaska, where the debris from four major landslides is easily distinguished from moraines and other supraglacial material. A series of aerial and satellite photos from 1972 to 2000 and field observations in 2001 and 2002 indicate that three of four landslides have fallen onto the surface of the glacier since about 1978. The landslides, which originated from the steeply dipping (60–70°) bedrock walls, were deposited onto the glacier in the ablation zone and are currently being transported downstream supraglacially. Individual glacial valleys with topographic relief of ∼400 m are cut into high‐grade metamorphic rock characterized by a steep north‐dipping foliation and fractured by numerous large joints. Measurements of landslide area and average thickness obtained from high‐resolution survey data indicate a total landslide volume of ∼2·3 × 105 m3. This volume suggests a basin‐averaged erosion rate from landslides of 0·48 mm a−1. An overall basin‐scale erosion rate of 0·7 to 1·7 mm a−1 can be inferred, but depends on the percentage of the total‐basin sediment yield contributed by supraglacial sources. A mean rockwall retreat rate of 6·7 mm a−1 is calculated and is considerably higher than published rates, which range from 0·04 to 4·0 mm a−1. Controls on landslide generation include seismicity, freeze–thaw processes, topography, rock strength, and debuttressing. It is likely all of these factors contribute to failure, although the primary controls for the landslides in this study are thought to be rock strength and topography. The absence of landslides on ten of the eleven glaciers on this ridge is attributed to landslide magnitude–frequency relationships and short temporal scale of this study. Large‐volume bedrock landslides (>100 000 m3) may have low frequency, occurring less than once in a 55‐year time frame. Copyright © 2005 John Wiley & Sons, Ltd.
Probabilistic formulation of conservation of cosmogenic nuclides: effect of surface elevation fluctuations on approach to steady state
Authors: Parker G. , Perg L. A.
Published: August 2005

Cosmogenic nuclides have provided a powerful tool for determining rates of landscape erosion. Once a steady‐state profile of cosmogenic nuclides is reached, the erosion rate becomes inversely proportional to the concentration of cosmogenic nuclides in the eroded sediment. Erosional landscapes are, however, subject to varying degrees of elevation fluctuations due to gullying, landsliding and bioturbation, for example. Here elevation fluctuation is described in terms of a probability density of deviation from mean elevation. A probabilistic formulation for the conservation of cosmogenic nuclides is derived so as to include the effect of the fluctuations. At steady state, the relation between the mean erosion rate and the concentration of cosmogenic radionucides in the eroded material becomes identical to that which would prevail in the absence of fluctuations. The fluctuations, however, can significantly lengthen the time required to reach steady state. Here the approach to steady state is studied in terms of (a) an impulsive increase in erosion rate starting from an antecedent steady state, and (b) a constant erosion rate but the initial absence of any cosmogenic nuclides. The problem allows an analytical solution. The effect of the fluctuations increases monotonically with increase in the ratio of the standard deviation of elevation fluctuations to the e‐folding penetration length of cosmic rays. Of prime importance to the practitioner is whether or not the concentration of cosmogenic nuclides in the eroded material has reached its steady‐state value. The central result of this paper is a simple plot allowing estimation of the time required to reach within a specified tolerance of the steady‐state value of this concentration. The time increases markedly with increase in the ratio defined above. The current formulation of the model is most applicable to weathering‐ or transport‐limited systems, e.g. badlands or landscapes dominated by deep‐seated landslides. Copyright © 2005 John Wiley & Sons, Ltd.
Quaternary relief generation by polythermal glacier ice
Authors: Staiger Jane K. W. , Gosse John C. , Johnson Jesse V. , Fastook James , Gray James T. , Stockli Daniel F. , Stockli Lisa , Finkel Robert
Published: August 2005

The juxtaposition of wet‐based erosive ice in valleys and cold‐based, non‐erosive ice atop felsenmeer‐covered interfluve plateaus has generated relief in the Torngat Mountains of northeastern Canada. Measurements of in situ terrestrial cosmogenic nuclide (TCN) concentrations from 31 bedrock sites, coupled with soils and geomorphology, indicate that erosion of the valleys has been >2 m during a single glacial–interglacial cycle. However, on summit plateaus the long‐term (over several glacial–interglacial cycles) erosion rate is <1·4 m Ma−1. TCN ratios reveal that the exposure plus ice‐cover history retained on some summit surfaces probably spans more than 800 ka despite complete ice cover as recently as 11 ka. A thermodynamic ice sheet model with a basal water calculation is used to calculate the sliding distance normalized by the duration of ice cover for the region. We formulate a general glacial erosion rule for the Torngat Mountains, which correlates TCN‐derived erosion rates for terrain once partially covered by cold‐based ice with modelled average ice basal sliding velocities. Erosion rates vary linearly with average sliding velocity by a glacial erosion coefficient of 5 × 10−7. Due to the significant distribution of cold‐based ice cover in this high latitude region, our estimates of net regional glacial erosion and glacial erosion coefficient are orders of magnitude lower than a previously published value. Copyright © 2005 John Wiley & Sons, Ltd.
The 7Be/210Pbxs ratio as an indicator of suspended sediment age or fraction new sediment in suspension
Authors: Matisoff Gerald , Wilson Christopher G. , Whiting Peter J.
Published: August 2005

Reported here is a technique to use the 7Be/210Pbxs ratio as a measure of suspended sediment age or as an indicator of the fraction of the suspended sediment that is recently eroded from the landscape. Although both 7Be and 210Pbxs are delivered seasonally and stochastically to the landscape by precipitation, the ratio of the two radionuclides varies substantially less. The 7Be/210Pbxs ratios measured in three different catchments decrease in the following manner: precipitation (c. 16) > suspended sediments in rivers (6–7) > suspended sediments in estuaries (4–6) > sediment collected in sediment traps in the estuary (c. 1) > surface sediment of the estuary (c. 0·5). Decreases in the 7Be/210Pbxs ratio in suspended sediments can be interpreted to be the result of increased age of the sediment, since 7Be decays faster than 210Pb. Alternatively, a decrease in the 7Be/210Pbxs ratio in suspended sediments can be interpreted to be the result of dilution of newly tagged 7Be‐rich sediment by 7Be‐dead sediment, for example, by erosion of soil below the 7Be‐enriched surface layer or by resuspension of 7Be‐dead bottom sediment. Presented here is a model which uses the 7Be/210Pbxs ratio in suspended sediments to determine the time since the particles were tagged by precipitation‐derived radionuclides (i.e. the age of the suspended sediment). In addition, an alternative model is presented to determine the fraction of the sediment that is ‘newly tagged’. These two models are applied to three catchments – Old Woman Creek, Ohio; Weeks Bay, Alabama; and South Slough, Oregon – and yield similar findings at all three sites. Sediment ages increase from 0 in newly tagged material, to 50–80 days in rivers, to about 80–100 days in the estuaries, to about 200 days in the sediment traps, to about 300 days on surface bottom sediments. Alternatively, the percentage new sediment decreases from 100 per cent in newly tagged material, to about 35–50 per cent in rivers, to 25–35 per cent in the estuary, to less than 10 per cent in the sediment traps, to 1–4 per cent on the surface of the bottom sediments.
Modelling granular sediment transport over water‐worked gravels
Authors: Hardy Richard J.
Published: August 2005

This paper reports a numerical model that calculates the transport paths of individual granular particles over a natural water‐worked gravel surface. Surface topography is measured using digital photogrammetry and incorporated into a computational fluid dynamics (CFD) scheme by the application of a porosity algorithm. The predicted hydraulics determine the forces acting on each particle enabling the particle trajectory to be solved by Langrangian transport equations. The methodology demonstrates the importance of including complex topography in the numerical scheme as topographically induced hydraulic acceleration and deceleration affect both the transport mechanism and subsequent trajectory of the particle. Hydraulically induced hops, where the particle is entrained into a localized shear layer around a bed particle, are demonstrated to be important in transporting granular sediment across the bed and in re‐starting sediment transport if the particle has fallen into a hydraulically sheltered region. Copyright © 2005 John Wiley & Sons, Ltd.
Children's understanding of mental states as causes of emotions
Authors: Rieffe Carolien , Terwogt Mark Meerum , Cowan Richard
Published: August 2005

Theory of mind studies of emotion usually focus on children's ability to predict other people's feelings. This study examined children's spontaneous references to mental states in explaining others' emotions. Children (4‐, 6‐ and 10‐year‐olds, n = 122) were told stories and asked to explain both typical and atypical emotional reactions of characters. Because atypical emotional reactions are unexpected, we hypothesized that children would be more likely to refer to mental states, such as desires and beliefs, in explaining them than when explaining typical emotions. From the development of lay theories of emotion, derived the prediction that older children would refer more often to mental states than younger children. The developmental shift from a desire‐psychology to a belief‐psychology led to the expectation that references to desires would increase at an earlier age than references to beliefs. Our findings confirmed these expectations only partly, because the nature of the emotion (happiness, anger, sadness or fear) interacted with these factors. Whereas anger, happiness and sadness mainly evoked desire references, fear evoked more belief references, even in 4‐year‐olds. The fact that other factors besides age can also play an influential role in children's mental state reasoning is discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Early communication in dyads with visual impairment
Authors: Rattray Julie , Zeedyk M. Suzanne
Published: August 2005

The ability of dyads with restricted access to the visual channel of communication to establish a reliable pre‐linguistic communicative signalling system has traditionally been viewed as problematic. Such a conclusion is due in part to the emphasis that has been placed on vision as central to communication by traditional theory. The data presented in this paper question these assertions. The results of a longitudinal study exploring the nature of early dyadic interactions in dyads with visual impairment are presented. The dyads' use of three types of non‐visual behaviour—touch, vocalizations and facial orientation—were investigated in terms of their potential as alternatives to visual communication. It is argued that the results are evidence that visually impaired dyads engage in sophisticated communicative exchanges prior to infants' acquisition of language. Copyright © 2005 John Wiley & Sons, Ltd.
Foldable micropatterned hydrogel film made from biocompatible PCL‐b‐PEG‐b‐PCL diacrylate by UV embossing
Authors: Zhu Ai Ping , Chan‐Park Mary B. , Gao Jian Xia
Published: August 2005

Foldable hydrogel films with micropatterns measuring 480 μm by 45 μm by 54 μm by 2 cm (width of microchannel by width of microwall by height of wall by length of pattern) were made by UV embossing of a block copolymer of polycaprolactone (PCL) and poly(ethylene glycol) (PEG), specifically PCL‐b‐PEG‐b‐PCL‐diacrylate (DA), with a polydimethylsiloxane mold. The mold was treated with Ar/CF4 plasma to simultaneously promote microchannel filling and demolding, and the glass substrate was modified with 3‐(trimethoxysilyl) propyl acrylate to promote hydrogel adhesion to avoid delamination of the gel during demolding. The micropatterned hydrogel film was detached from the glass substrate by freeze‐drying. As the films were demolded, the microstructured pattern was well replicated in the hydrogel. The gel pattern dimensions shrank with freeze‐drying and increased with water swelling, but under both conditions, the gel micropattern morphology was perfectly preserved. PCL‐b‐PEG‐b‐PCL‐DA hydrogel was found to have good biocompatibility compared with PEGDA hydrogel. A micropattern with a smaller microchannel width of 50 μm was also made. Micropatterned foldable and biocompatible hydrogel films have potential applications in the construction of tissue‐engineering scaffolds. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
A history of mass spectrometry in Australia
Authors: Downard Kevin M. , de Laeter John R.
Published: August 2005

An interest in mass spectrometry in Australia can be traced back to the 1920s with an early correspondence with Francis Aston who first visited these shores a decade earlier. The region has a rich tradition in both the development of the field and its application, from early measurements of ionization and appearance potentials by Jim Morrison at the Council for Scientific and Industrial Research (CSIR) around 1950 to the design and construction of instrumentation including the first use of a triple quadrupole mass spectrometer for tandem mass spectrometry, the first suite of programs to simulate ion optics (SIMION), the development of early TOF/TOF instruments and orthogonal acceleration and the local design and construction of several generations of a sensitive high‐resolution ion microprobe (SHRIMP) instrument. Mass spectrometry has been exploited in the study and characterization of the constituents of this nation's unique flora and fauna from Australian apples, honey, tea plant and eucalyptus oil, snake, spider, fish and frog venoms, coal, oil, sediments and shale, environmental studies of groundwater to geochronological dating of limestone and granite, other terrestrial and meteoritic rocks and coral from the Great Barrier Reef. Peter Jeffery's establishment of geochronological dating techniques in Western Australia in the early 1950s led to the establishment of geochronology research both at the Australian National University and at what is now the Curtin Institute of Technology in the 1960s.

This article traces the history of mass spectrometry in its many guises and applications in the island continent of Australia. An article such as this can never be complete. It instead focuses on contributions of scientists who played a major role in the early establishment of mass spectrometry in Australia. In general, those who are presently active in the field, and whose histories are incomplete, have been mentioned at best only briefly despite their important contributions to the field. Copyright © 2005 John Wiley & Sons, Ltd.
Capillary liquid chromatography and tandem mass spectrometry for the quantification of enkephalins in cerebrospinal fluid
Authors: Sinnaeve Bart A. , Storme Michael L. , Van Bocxlaer Jan F.
Published: August 2005

A capillary LC‐MS/MS system was evaluated for the absolute quantification of enkephalins in cerebrospinal fluid (CSF). On column focusing on a C18 trapping column, in‐line with the analytical column, was used for preconcentration. Quantification was performed with a triple quadrupole instrument in the multiple reaction monitoring mode. Weighted linear regression analysis proves to be a good linearity in a dynamic range of two orders of magnitude. The method was validated, yielding calibration curves with correlation coefficients greater than 0.9914. Assay precision and accuracy were evaluated by direct injection of enkephalin fortified artificial CSF (aCSF) samples at three concentration levels. Mean accuracy of analysed concentrations was between 97.63 and 107.6%. LOD and LOQ were assessed at, respectively, 0.5 and 1 pmol/mL. Validation results show that it is feasible, with a capillary LC‐MS/MS system, to quantify neuropeptides in the low femtomole range in aCSF. The obtained coefficients of variation, however, indicate that the use of appropriate isotopically labelled internal standards in neuropeptide quantification using narrow bore LC, combined with ESI‐MS, may be highly beneficial.
Silica monolithic columns: Synthesis, characterisation and applications to the analysis of biological molecules
Authors: Rieux Laurent , Niederländer Harm , Verpoorte Elisabeth , Bischoff Rainer
Published: August 2005

In recent years, proteomics has been a subject of intense research. The complexity of proteomics samples has fostered technological developments. One of these addresses the need for more efficient and faster separations. Monolithic columns prepared from organic and silica monomers offer very efficient separations at low backpressure. Silica‐based monoliths have small‐sized skeletons and a bimodal pore size distribution with μm‐sized throughpores and nm‐sized mesopores. This gives silica‐based monoliths favourable properties for high‐efficiency, fast separations, like a low‐pressure drop across the column, fast mass transfer kinetics and a high binding capacity.
Ionically Crosslinked Alginate/Carboxymethyl Chitin Beads for Oral Delivery of Protein Drugs
Authors: Shi Xiao‐Wen , Du Yu‐Min , Sun Li‐Ping , Yang Jian‐Hong , Wang Xiao‐Hui , Su Xue‐Li
Published: August 2005

Summary: Complex beads composed of alginate and carboxymethyl chitin (CMCT) were prepared by dropping aqueous alginate‐CMCT into an iron(III) solution. The structure and morphology of the beads were characterized by IR spectroscopy and scanning electron microscopy (SEM). IR confirmed electrostatic interactions between iron(III) and the carboxyl groups of alginate as well as CMCT, and the binding model was suggested as a three‐dimensional structure. SEM revealed that CMCT had a porous morphology while alginate and their complex beads had a core‐layer structure. The swelling behavior, encapsulation efficiency, and release behavior of bovine serum albumin (BSA) from the beads at different pHs were investigated. The BSA encapsulation efficiency was fairly high (>90%). It was found that CMCT disintegrated at pH 1.2 and alginate eroded at pH 7.4 while the complex beads could effectively retain BSA in acid (>85%) and reduce the BSA release at pH 7.4. The results suggested that the iron(III)‐alginate‐CMCT bead could be a suitable polymeric carrier for site‐specific protein drug delivery in the intestine.

Iron(III)‐alginate‐CMCT beads crosslinked in ferric chloride.

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Iron(III)‐alginate‐CMCT beads crosslinked in ferric chloride.
In vitro Biological Performances of Phosphorylcholine‐Grafted ePTFE Prostheses through RFGD Plasma Techniques
Authors: Chevallier Pascale , Janvier Richard , Mantovani Diego , Laroche Gaétan
Published: August 2005

Summary: Arterial prostheses made of microporous Teflon® (ePTFE) are currently used in vascular surgery as bypasses for small and medium vessels. However, several clinical complications, such as thrombosis, frequently occur in these prostheses when implanted in humans. In this work, an original strategy was developed to improve the hemocompatibility of ePTFE prostheses, based on glow‐discharge surface modification followed by chemical grafting of phosphorylcholine, known for its hemocompatible properties. This procedure leads to a covalent attachment of the molecules, therefore preventing their removal by shear stress induced by blood flow at the implant wall. The improvement of the blood compatibility properties of the modified ePTFE arterial prostheses have been investigated by in vitro tests such as thromboelastography, neutrophil adsorption, platelet aggregation, and cell cultures. These in vitro tests put in evidence that thrombogenicity index, platelet aggregation, and neutrophil adhesion were decreased by the molecule grafted on the prostheses. Moreover, the cell growth on the surface of the PRC‐grafted prostheses was greatly enhanced in comparison to the virgin prosthesis. Based on these results, it could be concluded that PRC grafting on ePTFE prostheses permit to improve in vitro hemocompatibility and biocompatibility in comparison with their virgin counterpart.

Phosphorylcholine grafting onto ammonia plasma‐treated ePTFE prosthesis and its influence on fibroblast growth.

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Phosphorylcholine grafting onto ammonia plasma‐treated ePTFE prosthesis and its influence on fibroblast growth.
Functional Films of Maleic Anhydride Copolymers under Physiological Conditions
Authors: Pompe Tilo , Renner Lars , Grimmer Milauscha , Herold Nicole , Werner Carsten
Published: August 2005

Summary: Reactivity and swelling of nanometer films of alternating maleic anhydride copolymers were investigated in dependence on the kind of comonomer and molar mass of copolymer in aqueous solution at pH 7.4 and pH 3.0 in order to reveal their characteristics under physiological conditions. Fully hydrolyzed (maleic acid) chains of the copolymers with styrene, propene, and ethylene comonomers covalently bound to SiO2 substrates showed a “mushroom” swelling behavior at pH 7.4 with a layer thickness scaling of N3/5. Decreasing the environmental pH was found to induce a comonomer‐dependent shrinking or collapse of the immobilized polymers due to the change in ionization. From the swelling kinetics of non‐hydrolyzed chains, the time constants and characteristics of swelling and anhydride hydrolysis were determined and found to depend on the type of comonomer. The short‐ and long‐term swelling kinetics [l ∼ t and ∼ln(t)1/2] were found to be in agreement with theoretical models of polymer swelling, while at intermediate time scales enhanced swelling was observed due to hydrolysis reaction of maleic anhydride groups. The findings elucidate the variety of properties of maleic anhydride copolymer films under physiological conditions, which can advantageously be applied for biofunctionalization of different templates.

Swelling of nanometer films of alternating maleic anhydride copolymers in aqueous solution at pH 7.4 and pH 3.0.

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Swelling of nanometer films of alternating maleic anhydride copolymers in aqueous solution at pH 7.4 and pH 3.0.
Cover Picture: Macromol. Chem. Phys. 17/2005
Authors: Andou Yoshito , Yasutake Mikio , Jeong Jae‐Mun , Nishida Haruo , Endo Takeshi
Published: August 2005

Cover: Gas‐phase assisted surface polymerization (GASP) of methyl methacrylate (MMA) with a simple initiating system, Fe(0)/α‐bromophenylacetate (MBPA), produced high molecular weight PMMA on Fe(0)‐metal surfaces, suggesting a physically controlled propagation process on the surfaces. Further details can be found in the Full Paper by Y. Andou, M. Yasutake, J.‐M. Jeong, H. Nishida,* and T. Endo on page 1778.
Experimental evidence on trading behavior, market efficiency and price formation in double auctions with unknown trading duration
Authors: Duxbury Darren
Published: August 2005

The reasons for the highly efficient market outcomes observed under the double auction remain unclear. This paper presents a series of experimental financial markets designed to investigate the importance of unknown trading period duration on trading behavior and the convergence tendencies of such markets. Using panel data techniques the results support the conclusions that individuals generally display more aggressive trading strategies, trading earlier in a period, and that markets exhibit reduced levels of informational efficiency when unknown duration is present. Markets with imperfect information structures are also studied and, in a unique result, are associated with significantly slower rates of trade, as traders become more cautious over their trading strategies. Investigation of the price formation process provides evidence that the pricing error varies over time and the estimation of a fixed effects model provides unique support that learning effects and unknown trading period duration influence the price formation process. Future refinement of theoretical models of the price formation process or institutions of exchange should recognize the effect of unknown trading period duration on market behavior, along with potential learning effects. Copyright © 2005 John Wiley & Sons, Ltd.
The limits of the wage impact of discrimination
Authors: Becker Elizabeth , Lindsay Cotton M.
Published: August 2005

In spite of almost 40 years of active enforcement efforts by the EEOC, as well as the strong intervention by the plaintiff bar, the most popular benchmark by which we measure the influence of prejudice on wages paid to female and minority workers has changed very little. This paper maintains that to a large extent this seeming immunity of discriminatory wage gaps to the legal remedies provided by Title VII results from the mismeasurement of those effects. An alternative to the standard Oaxaca decomposition of the wage gap is offered which allows us to put plausible ranges around the true impact of antidiscrimination laws. Not only does this reduce the residual impact of the discrimination that appears to withstand Title VII remedies, it also suggests that the pre‐Title VII impact of discrimination on wages accounted for little of the gap observed at the time of its passage. Copyright © 2005 John Wiley & Sons, Ltd.
The mystification of operational competitiveness rating analysis
Authors: Wang Shouhong , Wang Hai
Published: August 2005

This note examines the fault of the operational competitiveness rating analysis (OCRA) method. The premise of the OCRA method requires that a single scalar measurement must be applied to inputs and outputs to calculate the performance ratings for production units. This property renders the OCRA method worthless, since simple comparisons of the aggregated inputs and outputs can generate accurate productive efficiency evaluation results for production units if the simple aggregation can be done. To avoid this problem, the OCRA method includes subjective weighting elements for input and output categories, so called calibration constants, into the performance rating computation. This approach of the OCRA method introduces much confusion for productive efficiency evaluation, and it violates the economics axiom of output/input maximization in its application context. Copyright © 2005 John Wiley & Sons, Ltd.
Managing energy consumption costs in desktop PCs and LAN switches with proxying, split TCP connections, and scaling of link speed
Authors: Gunaratne Chamara , Christensen Ken , Nordman Bruce
Published: August 2005

The IT equipment comprising the Internet in the USA uses about $6 billion of electricity every year. Much of this electricity use is wasted on idle, but fully powered‐up, desktop PCs and network links. We show how to recover a large portion of the wasted electricity with improved power management methods that are focused on network issues. Copyright © 2005 John Wiley & Sons, Ltd.
IP layer load balance using fuzzy logic under IPv6 anycast mechanism
Authors: Chang Chi‐Yuan , Chen Wei‐Ming , Chao Han‐Chieh , Tsuei T. G. , Liu Hong Bin
Published: August 2005

With the emergence of databases and Internet technology, the way data is acquired and accessed has changed with more convenient service. After years of evolution, the current IPv6 Internet Protocol (IP) has enabled the user to check any database worldwide by logging onto the Internet whenever you want and regardless of where you are. The load balance or efficiency issue arises when many users overload a server or database. This paper addresses this issue using the anycast characteristics. An active router design is developed to receive the server load information. This information is in turn used to determine the server's response to solve the load balance problem. Copyright © 2005 John Wiley & Sons, Ltd.
Toward best maintenance practices in communications network management
Authors: Kamoun Faouzi
Published: August 2005

Best maintenance practices in communications networks management are benchmarking standards that, if carefully implemented, will enhance the integrity, reliability and maintenance costs of communications networks. This paper defines best maintenance practices in communications network management within a concise framework encompassing measurable performance‐level goals as well as methods and procedures needed to achieve these goals. The best maintenance practice recommendations of this paper cover many segments of communications networks and services, including wireline and wireless networks as well as multiple network spaces and technologies. The paper also outlines certain recent trends in network maintenance and provides specific recommendations for action to be taken to ensure that best network maintenance practices are implemented and maintained. Copyright © 2005 John Wiley & Sons, Ltd.
Management of mobile ad hoc networks: information model and probe‐based architecture
Authors: Badonnel Remi , State Radu , Festor Olivier
Published: August 2005

The increasing need for mobility in networks and computing leads to the deployment of wireless networks without fixed infrastructure, called ad hoc networks. These networks raise new challenges towards monitoring and managing them to provide optimal performance. We propose in this paper a management framework to assess the operational state and the behaviour of mobile ad hoc networks. After presenting the management requirements, we define an information model to manage these networks. Simulations provide an overview of how this model can be used. Finally, we describe a probe‐based architecture with an implementation prototype, to use and populate the information model in a realistic environment. Copyright © 2005 John Wiley & Sons, Ltd.
Enterprise resource planning: a review and a STOPE view
Authors: Bakry Ali Haj , Bakry Saad Haj
Published: August 2005

Enterprise resource planning (ERP) systems are becoming of increasing importance as integrated parts of business networks. They support ‘e‐business implementation’ for better enterprise performance, ‘integrate activities’ for higher enterprise efficiency, and enjoy a ‘modular architecture’, for future extensions and further benefits. The aim of this review is to introduce ERP systems and explore their current state and future potentials. Using recent literature, the review provides a comprehensive understanding of ERP systems, including illustrating their main components and clarifying their basic and extended features. In addition, the review highlights the main producers of ERP systems, together with their partners and customers. Based on previous investigations, the review also addresses ERP selection criteria and critical implementation factors. Finally, recent views of ERP systems and their future development, including their enhanced intelligence, expansion, and management, are given. The views also include a STOPE view (strategy, technology, organization–enterprise, people, environment), which illustrates the integration of ERP systems with the overall enterprise network. Copyright © 2005 John Wiley & Sons, Ltd.
The trade‐off between cardiovascular and gastrointestinal effects of rofecoxib
Authors: Florentinus Stefan R. , Heerdink Eibert R. , Boer Antonius de , van Dijk Liset , Leufkens Hubert G.M.
Published: August 2005

The original article to which this Erratum refers was published in Pharmacoepidemiology and Drug Safety, 14 (7) 2005, 437–441.

No Abstract.
Peroxisomal proteomics, a new tool for risk assessment of peroxisome proliferating pollutants in the marine environment
Authors: Mi Jia , Orbea Amaia , Syme Neil , Ahmed Meftun , Cajaraville Miren P. , Cristóbal Susana
Published: August 2005

In an attempt to improve the detection of peroxisome proliferation as a biomarker in environmental pollution assessment, we have applied a novel approach based on peroxisomal proteomics. Peroxisomal proteins from digestive glands of mussels Mytilus galloprovincialis were analyzed using 2‐DE and MS. We have generated a reference 2‐DE map from samples obtained in a well‐studied reference area and compared this with peroxisomal proteomes from other sequenced genomes. In addition, by comparing 2‐DE maps from control samples with samples obtained in a polluted area, we have characterized the peroxisome proliferation expression pattern associated with exposure to a polluted environment. Over 100 spots were reproducibly resolved per 2‐DE map; 55 differentially expressed spots were quantitatively detected and analyzed, and 14 of these showed an increase in protein expression of more than fourfold. Epoxide hydrolase, peroxisomal antioxidant enzyme, and sarcosine oxidase (SOX) have been identified by ESI MS/MS, and acyl‐CoA oxidase, multifunctional protein, and Cu,Zn‐superoxide dismutase were immunolocalized by Western blotting. Our results indicate that a peroxisomal protein pattern associated to marine pollutant exposure can be generated, and this approach may have a greater potential as biomarker than traditional, single‐protein markers.
Expression of fragile X mental retardation‐1 gene with nuclear export signal mutation changes the expression profiling of mouse cerebella immortal neuronal cell
Authors: Hu LiPing , Chen YuTing , Evers Stefan , Shen Yan
Published: August 2005

Fragile X syndrome (FXS) is the most frequent cause of inherited mental retardation and is largely caused by a loss of expression of fragile X mental retardation protein (FMRP), encoded by fragile X retardation gene‐1 (Fmr1). FMRP is a multifunction protein, with intrinsic RNA‐binding properties, which is a component of ribonucleoprotein complex associated with polyribosomes. The properties of FMRP indicate that it might participate in post‐transcriptional processes in the regulation of some mRNA species, including localization, stability and translational control. However, the function of FMRP related to the pathologenesis in FXS is largely unknown. Many efforts were undertaken to identify the putative specific RNA targets as well as the FMRP‐related proteins and to identify the effect of FMRP absence on the corresponding proteins. Here we present our efforts using proteomics approach to explore the differential expression profiling of mouse cerebella immortal cell, in which we changed the expression of FMRP by expressing Fmr1 gene with nuclear export signal (NES) mutation. This mutation makes FMRP unable to shuttle from nucleus to cytoplasm and leads to nuclear instead of cytoplasmic location as usual, which was hypothesized to affect the pathways of groups of RNAs or proteins related with FMRP. In present study, 56 proteins were found to be differentially expressed in transfected R2 neuronal cells, including 16 decreased expressions and 40 increased expressions. The differentially expressed proteins play roles in diverse physiological processes, such as neuronal plasticity, spermatogenesis and craniofacial and limb development etc. In addition, the expressions of three mRNA identified as FMRP targets in fragile X cell were tested in present model cells. All these results provide new insights to the role of FMRP in the disease.
Immunodepletion of albumin for two‐dimensional gel detection of new mouse acute‐phase protein and other plasma proteins
Authors: Duan Xunbao , Yarmush David , Berthiaume François , Jayaraman Arul , Yarmush Martin L.
Published: August 2005

Immunodepletion of albumin to improve the 2‐D gel resolution of human plasma proteins has recently been described. With the importance of mouse models in many studies in which serum or plasma is often analyzed, we have adopted this approach to immunoprecipitate mouse albumin and evaluated its effectiveness for 2‐D separation of mouse plasma proteins. Purified polyclonal antibodies against mouse albumin were effective depleting intact albumin as well as its numerous fragments from mouse plasma samples. Removal of albumin resulted in better resolution of mouse plasma proteins. Three proteins, α2‐macroglobulin, coagulation factor XII, and hemopexin, that were previously either undetectable or poorly resolved, were identified from albumin‐depleted 2‐D gels by peptide mass fingerprinting. Albumin depletion also led to partial loss of several other proteins such as clusterin and gelsolin. This loss can be attributed to the interaction with albumin itself because the specificity of the antibody was demonstrated by Western blot. When applying this method to the 2‐D separation of plasma from inflamed mouse induced by cutaneous burn injury with superimposed Pseudomonas aeruginosa infection, the upregulation of inter α‐trypsin inhibitor heavy chain 4 (ITIH4) and hemopexin was unambiguously detected along with other mouse acute‐phase proteins (APP), including haptoglobin and serum amyloid A. Based on the significant increase of ITIH4, we propose that this protein is a new member of mouse APP that are upregulated during the inflammatory response.
Simple and effective technical procedures for the packing and application of nanospray PicoFrit HPLC columns for proteomic analyses
Authors: Howells Laurence C. , Whelan Adam O. , Woodward Martin J. , Coldham Nick G.
Published: August 2005

A simple procedure was developed for packing PicoFrit HPLC columns with chromatographic stationary phase using a reservoir fabricated from standard laboratory HPLC fittings. Packed columns were mounted onto a stainless steel ultra‐low volume precolumn filter assembly containing a 0.5‐µm pore size steel frit. This format provided a conduit for the application of the nanospray voltage and protected the column from obstruction by sample material. The system was characterised and operational performance assessed by analysis of a range of peptide standards (n = 9).
Self‐made frits for nanoscale columns in proteomics
Authors: Maiolica Alessio , Borsotti Dario , Rappsilber Juri
Published: August 2005

We report here the production of self‐made frits for nano‐columns. The frits introduce a minor dead volume and can be placed in capillaries with a wide range of diameters (20–250 µm tested) in an extremely simple and low‐cost procedure. The obtained columns appear to be comparable to “no‐frit” columns with near‐ideal chromatographic characteristics. We expect that this frit will be useful for the spotting of gradients onto MALDI plates but also where special ESI set‐ups do not allow for “no‐frit” solutions.
Protein kinase C‐mediated phosphorylation of orphan nuclear receptor TR2: Effects on receptor stability and activity
Authors: Khan Shaukat Ali , Park Sung Wook , Huq Mostaqul , Wei Li‐Na
Published: August 2005

In vivo metabolic labeling showed that orphan nuclear receptor TR2 could be phosphorylated. Systematic studies were conducted using specific kinases/phosphatase inhibitors to determine the enzymes responsible for TR2 phosphorylation and the effects of TR2 phosphorylation on its protein stability and activation of its target gene. The data showed that protein kinase C (PKC)‐mediated phosphorylation enhanced the activating ability of TR2 on target gene RARβ as well as its stability through protection from proteosome‐mediated degradation. Several PKC‐mediated potential serine/threonine phosphorylation sites on TR2 protein were predicted from the computer analysis using NetPhos software (http://us.expasy.org) and were commensurate by in vitro phosphorylation of purified TR2 protein using PKC enzyme. Two phosphorylation sites at Ser‐461 and Ser‐568 were identified by LC‐ESI‐MS/MS. Point mutations at Ser‐568 or Ser‐461 were prepared and evaluated for their biological activity. Ser‐568, but not Ser‐461, mutation significantly reduced PKC‐mediated TR2 protein stability and its transcriptional activity.
Double‐layered composite nanofibers and their mechanical performance
Authors: Huang Zheng‐Ming , Zhang Yanzhong , Ramakrishna S.
Published: August 2005

Continuous polymer nanofibers are available through electrospinning, but most have the same structure in their cross section. This article focuses on the fabrication and the structural and mechanical characterization of pencil‐like double‐layered composite nanofibers coaxially electrospun from solutions of two different biodegradable materials, i.e., gelatin and poly(ε‐caprolactone) (PCL). Transmission electron microscopy and water contact angle measurements confirmed that a gelatin inner fiber was wrapped with a PCL outer layer. Possible applications of such nanofibers include a controlled degradation rate when used as a medical device in human body. It has been found that the tensile performance of the composite nanofibers was better than those of both the pure constituent, i.e. gelatin and PCL, nanofibers alone. The ultimate strength and ultimate strain of the composite nanofibers with 7.5% w/v gelatin in the core and 10% w/v PCL as shell were at least 68% and 244% higher, respectively, than those of the same concentration pure gelatin and PCL nanofibers. Thus, a coaxial electrospinning technique as used in this article can be applicable, not only in developing functionalized nanofibers but also in elevating their mechanical property. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2852–2861, 2005
Elastic properties and mechanical relaxation behaviors of PVDF (poly (vinylidene fluoride)) at temperatures between −20 and 100 °C and at 2 MHz ultrasonic frequency
Authors: Guney H. Yuksel
Published: August 2005

The elastic properties of PVDF have been investigated as a function of temperature. The propagation velocity and absorption of longitudinal and transverse ultrasonic waves have been measured at a constant frequency of 2 MHz and temperatures between –20 and 100 °C. Hence, the temperature dependences of storage and loss elastic constants have been obtained for temperatures between –20 and 100 °C. It has been seen that the relaxation behavior is affected from the form of mechanical disturbance. For the longitudinal mode, only one relaxation peak at 42 °C, but for transverse mode three relaxation peaks at 28 °C, 60 °C, and 94 °C have been observed. The results have been compared with the literature values obtained previously for PVDF. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2862–2873, 2005
Development of HIV fusion inhibitors
Authors: Schneider Stephen E. , Bray Brian L. , Mader Catherine J. , Friedrich Paul E. , Anderson Mark W. , Taylor Tracy S. , Boshernitzan Natalia , Niemi Toivo E. , Fulcher Brian C. , Whight Sheila R. , White Jonathan M. , Greene Reagan J. , Stoltenberg Larry E. , Lichty Maynard
Published: August 2005

In the past 25 years, the worldwide AIDS epidemic has grown such that roughly 38 million people were estimated to be living with the disease worldwide at the end of 2003. The introduction of antiretroviral‐based therapies, beginning in 1987, has enabled many to live with HIV as a chronic, rather than terminal, disease. However, the emergence and spread of drug‐resistant strains highlights the continued need for new therapies with novel modes of action. In 2003, the FDA and EMEA approved enfuvirtide (Fuzeon), a 36 amino acid peptide derived from the natural gp41 HR2 sequence, as the first HIV fusion inhibitor. T‐1249, a 39 amino acid fusion inhibitor, is active against viruses that develop resistance to enfuvirtide. The development of FIs and the processes to manufacture enfuvirtide and T‐1249 on an unprecedented scale for peptide therapeutics are presented. Synthetic routes based on a combination of solid phase peptide synthesis and solution phase fragment condensation as well as the analytical controls necessary to insure a robust process are discussed. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd.