bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth velocity assessment in paediatric AIDS: smoothing, penalized quantile regression and the definition of growth failure
Authors: Carey V. J. , Yong F. H. , Frenkel L. M. , McKinney R. M.
Published: January 2004

The analysis of growth records in paediatric anti‐HIV clinical trials plays an important role in trial evaluation. Growth failure may be a manifestation of progressive disease or treatment toxicity, and is commonly specified as a major trial outcome event indicating poor treatment performance. Despite new therapeutic advances against HIV proliferation in infected patients, accurate monitoring and interpretation of somatic growth in paediatric AIDS remains clinically important, in light of uncertainties regarding relationship between viral load reductions and achievement of favourable somatic growth profiles. Our aim in this paper is to construct a criterion for growth failure that discriminates patients whose risk of death subsequent to growth failure is elevated to a clinically significant degree. To construct the criterion, individual growth curves and velocities are modelled using loess smoothing, penalized likelihood quantile regressions are fit to model age‐specific growth velocity distributions for gender‐stratified cohorts, and proportional hazards model selection is conducted to identify features of velocity series that are informative on the survival distribution. The resulting growth‐failure criterion is expected to be useful for disease staging in resource‐limited medical environments where T‐cell counts and viral load measures are unavailable. Copyright © 2003 John Wiley & Sons, Ltd.
Estimation of genetic and environmental factors for binary traits using family data
Authors: Pawitan Y. , Reilly M. , Nilsson E. , Cnattingius S. , Lichtenstein P.
Published: January 2004

While the family‐based analysis of genetic and environmental contributions to continuous or Gaussian traits is now straightforward using the linear mixed models approach, the corresponding analysis of complex binary traits is still rather limited. In the latter we usually rely on twin studies or pairs of relatives, but these studies often have limited sample size or have difficulties in dealing with the dependence between the pairs. Direct analysis of extended family data can potentially overcome these limitations. In this paper, we will describe various genetic models that can be analysed using an extended family structure. We use the generalized linear mixed model to deal with the family structure and likelihood‐based methodology for parameter inference. The method is completely general, accommodating arbitrary family structures and incomplete data. We illustrate the methodology in great detail using the Swedish birth registry data on pre‐eclampsia, a hypertensive condition induced by pregnancy. The statistical challenges include the specification of sensible models that contain a relatively large number of variance components compared to standard mixed models. In our illustration the models will account for maternal or foetal genetic effects, environmental effects, or a combination of these and we show how these effects can be readily estimated using family data. Copyright © 2004 John Wiley & Sons, Ltd.
Estimation of reporting delay and suicide incidence in Hong Kong
Authors: Cui Jisheng S. , Yip Paul S. F. , Chau P. H.
Published: January 2004

This paper uses a semi‐parametric method to examine the reporting delay distribution in suicides in Hong Kong reporting system. The data arise from a rightly truncated situation in which only suicide cases registered before a specific time are known to have occurred; otherwise they are not recorded in the known death files even if they have occurred. It is shown that the poisoning‐related suicide deaths have a longer reporting delay than other suicide methods. By modelling the reporting delay function, a Horvitz–Thompson‐type estimator is suggested to adjust for reporting delay and to provide a more timely estimate of the suicide incidences for monitoring the suicide problem in Hong Kong. Based on these analyses, we recommended a suitable cut‐off date to collect suicide cases occurring in the previous year and reported before this date in Hong Kong. Copyright © 2004 John Wiley & Sons, Ltd.
A log‐normal distribution model of the effect of bacteria and ear fenestration on hearing loss: a Bayesian approach
Authors: Gajewski Byron J. , Sedwick Jack D. , Antonelli Patrick J.
Published: January 2004

Chronic ear infection is a potentially life‐threatening illness that medical doctors typically treat with ear surgery. Despite the success of this treatment, complications can occur due to bacteria infection. Surgeons believe that this infection causes the patient to have clinically significant hearing damage. In order to understand such complications, surgeons must quantify the effect of bacteria, their toxins and ear surgery on hearing loss. To this end, the other two authors of this paper performed two experiments on guinea pigs to measure hearing thresholds following a bacterial infection and surgery of the inner ear. The response variable in these experiments is hearing thresholds measured in decibels (dB). The problem in analysing such experiments is that the hearing threshold observations often suffer from missing data and censoring mechanisms of various types. Additionally, the distribution of hearing thresholds has heavy tails and is peaked. In order to account for the above statistical issues, we present a Bayesian method with a location‐shifted log‐normal distribution. The method accounts for the uncertainty in the data collection mechanism and the parameters associated with a location‐shifted log‐normal distribution. We refer to one of the parameters as the ‘location‐shift’ parameter. The Bayesian approach provides a posterior distribution of the location‐shift parameter that we compare with values estimated in previously published studies. The immediate goal of our proposed method was to quantify the effects of ear surgery and bacteria infection on hearing loss. Thus, we present the merits of the method in the form of a case study, and report posterior distributions of mean hearing loss, probability of clinically significant hearing loss and relative risk. The results show that surgeon 2, using the surgical procedure ‘oval window’, poses a greater than 40 per cent chance of a 15dB hearing loss regardless of injection of bacteria or not. However, surgeon 1, using the surgical procedure ‘semicircular canal’, does not pose a significantly greater than 40 per cent chance of a 15dB hearing loss unless there is a Pseudomonas aeruginosa‐induced infection. Copyright © 2004 John Wiley & Sons, Ltd.
Optimal designs for Michaelis–Menten kinetic studies
Authors: Matthews J. N. S. , Allcock G. C.
Published: January 2004

Many reactions in enzymology are governed by the Michaelis–Menten equation. Characterising these reactions requires the estimation of the parameters KM and Vmax which determine the Michaelis–Menten equation and this is done by observing rates of reactions at a set of substrate concentrations. The choice of substrate concentrations is investigated by determining Bayesian D‐optimal designs for a model in which residuals have a normal distribution with constant variance. Designs which focus on alternative quantities, such as KM or the ratio Vmax/KM are also considered. The effect on the optimal designs of alternative error distributions is also considered. Copyright © 2004 John Wiley & Sons, Ltd.
Doing business in Brazil: A strategic approach
Authors: Gouvea Raul
Published: January 2004

Brazil has the largest economy in South America, and the second largest in Latin America, offering one of the most promising markets in the world. Along with China and India, Brazil is ranked among the nations with the highest predicted development rates in the next 25 years.

In the early 2000s, Brazil accounted for 56% of all foreign direct investment flows to South America and 52.5% of the foreign direct investment stock in South America. Brazil is also a key player in the design and development of the Free Trade Agreement of the Americas (FTAA), which is scheduled to be effective by 2005. The FTAA is expected to be the world's largest regional trading block.

In 2002, Brazil was ranked twelfth amongst the largest economies in the world. Brazil is one of the world's “Big Five” emerging markets, along with China, India, Mexico, and Indonesia. In the past decade, Brazil was second to China among emerging economies for received foreign direct investment.

This article elaborates on the main aspects of doing business in Brazil and discusses some of the challenges and opportunities facing the Brazilian economy. © 2004 Wiley Periodicals, Inc.
Online/offline (hybrid) consumers and the attention economy
Authors: Rau Pradeep A.
Published: January 2004

Yoram (Jerry) Wind, Vijay Mahajan, & Robert Gunther. 2002. Convergence Marketing:
Strategies for Reaching the New Hybrid Consumer. Upper Saddle River, NJ: Prentice Hall. 368 pages. ISBN
0‐13065‐075‐7.

Thomas H. Davenport & John C. Beck. 2001. The Attention Economy: Understanding the New Currency of
Business. Boston, MA: Harvard Business School Press. 272 pages. ISBN
1‐57851‐871‐7.
Rapid rise of China's semiconductor industry: What are the implications for Singapore?
Authors: Wu Friedrich , Loy Chua Boon
Published: January 2004

Lately, there has been a rush of foreign investment commitments in China's semiconductor industry, giving
rise to predictions of a semiconductor revolution in the world's most populous country. Pull factors include
China's entry into the World Trade Organization (WTO), which would clarify trading and investment
rules, government incentives, and, of course, burgeoning domestic demand.

For the moment, because of U.S. export restrictions, China's chip industry will be kept behind the
technology curve by around five years. However, its ample supply of engineers and low labor costs will aid in the
development of the assembly & test and design sectors, which are labor‐intensive. But given strong
government commitment, the industry is likely to continue to progress upward, gaining from the diffusion of
high‐tech know‐how through its alliances with multinational corporations and tier‐one
foundries. In the industry's value chain, there is potential for Taiwan and China to complement each other in
both domestic and global markets, across both high‐ and low‐end technology segments, and across the
entire chain of activities.

To meet the challenges, Singapore needs to further leverage on its competencies in infrastructure and logistics,
as well as the well‐established ASEAN production network for greater economies of scale. For Singapore's
semiconductor industry to remain competitive, there is a need to strengthen the full value chain, from integrated
circuit (IC) design to wafer fabrication to packaging & test, by attracting and building up companies
specializing in different competencies. Singapore semiconductor manufacturers should continuously strive to stay at
the technology forefront and provide competitive customer services. © 2004 Wiley Periodicals, Inc.
Dissociative disorders among psychiatric patients
Authors: Lipsanen Tapio , Korkeila Jyrki , Peltola Päivi , Järvinen Johanna , Langen Katja , Lauerma Hannu
Published: January 2004

The aim was to determine the rate of dissociative disorders among psychiatric in- (n= 34) and out-patients (n= 37) and to compare the rate to that of nonclinical subjects (n= 297). Dissociative disorders (17% of patients) could be grouped according to the severity of the symptoms and their relation to affective disorders.
Age and growth of redfish (Sebastes marinus, S. mentella, and S. fasciatus) on the Flemish Cap (Northwest Atlantic)
Authors: Saborido-Rey Fran , Garabana Dolores , Cerviño Santiago
Published: January 2004

Age determination of redfish is difficult. In this paper, the ages of Sebastes mentella on the Flemish Cap are validated by following year classes from 1991 to 2000. The criteria used for S. mentella are consistent and coherent. The growth of different year classes is described and compared, and density-dependence is demonstrated to influence the growth rate of the strong 1990 year class, growth of that year class being the slowest of those followed. The slow rate of growth prevented that year class from maturing at the anticipated age. Growth is also compared between sexes, of S. mentella, S. marinus, and S. fasciatus, revealing that females grow faster than males. Finally, growth rate is compared among species. S. marinus grows fastest and S. mentella slowest, although the influence of density-dependent growth in S. mentella needs to be taken into consideration.
Contralateral response of macrophages and astrocytes to injury in the cerebral hemisphere of 6‐day‐old rat following prenatal gamma irradiation
Authors: Setkowicz Zuzanna , Bień Ewa , Janeczko Krzysztof
Published: January 2004

Wistar pregnant rats were exposed to a single 1.0 Gy dose of gamma rays on gestational days 13, 15, 17 or 19 (E13, E15, E17 and E19, respectively). When offsprings of the irradiated females became 6‐day‐old, they received a mechanical injury of the cerebral hemisphere. One or 2 days after the injury, [3H]thymidine was injected and the animals were perfused. Brain sections were processed for BSI‐B4 isolectin histochemistry or immunohistochemistry for glial fibrillary acidic protein (GFAP) or S‐100‐β protein and subjected to autoradiography to visualise proliferating and non‐proliferating macrophages or proliferating astrocytes. Significant changes in the contralateral response to injury related to the day of prenatal irradiation could be detected. The response was minimal following irradiations performed on E15 and E17. At those stages of prenatal development, the majority of cortical neurons with interhemispheric connections were formed. Therefore, irradiation‐induced reduction of the neurons might minimise transfer of pathogenic stimuli to contralateral areas via degenerating nerve fibbers. Consequently, the degree at which the contralateral glial response reflected reactive changes at the lesion site might also be minimal. Results of the present study do not show in detail mechanisms underlying the differences in the contralateral reactivity to injury. They, however, might be of importance to histopathological investigations using animal models of cerebral dysplasia.
New measurement scales for evaluating perceptions of the technology‐mediated customer service experience
Authors: Froehle Craig M. , Roth Aleda V.
Published: January 2004

Service organizations are increasingly utilizing advanced information and communication technologies, such as the Internet, in hopes of improving the efficiency, cost‐effectiveness, and/or quality of their customer‐facing operations. More of the contact a customer has with the firm is likely to be with the back‐office and, therefore, mediated by technology. While previous operations management research has been important for its contributions to our understanding of customer contact in face‐to‐face settings, considerably less work has been done to improve our understanding of customer contact in what we refer to as technology‐mediated settings (e.g., via telephone, instant messaging (IM), or email). This paper builds upon the service operations management (SOM) literature on customer contact by theoretically defining and empirically developing new multi‐item measurement scales specifically designed for assessing technology‐mediated customer contact. Seminal works on customer contact theory and its empirical measurement are employed to provide a foundation for extending these concepts to technology‐mediated contexts. We also draw upon other important frameworks, including the Service Profit Chain, the Theory of Planned Behavior, and the concept of media/information richness, in order to identify and define our constructs. We follow a rigorous empirical scale development process to create parsimonious sets of survey items that exhibit satisfactory levels of reliability and validity to be useful in advancing SOM empirical research in the emerging Internet‐enabled back‐office.
Lengthening of double‐looped tendon graft constructs in three regions after cyclic loading: A study using Roentgen stereophotogrammetric analysis
Authors: Roos P. J. , Hull M. L. , Howell S. M.
Published: January 2004

Lengthening of a double‐looped tendon graft construct used to reconstruct the anterior cruciate ligament (ACL) can result in an increase in anterior knee laxity and affect the stability of the reconstructed knee. Three possible regions where lengthening of the construct can occur are (1) the region of the tibial fixation, (2) the region of the femoral fixation, and (3) the region of the graft between the fixations. One objective of this study was to demonstrate the feasibility of using Roentgen stereophotogrammetric analysis (RSA) to determine the lengthening in each region of a double‐looped graft construct subjected to cyclic loading. A second objective was to determine which region(s) contributes most to an increase in length of this graft construct. Radio‐opaque markers were attached to ten grafts to measure the lengthening in each of the three regions. Each graft was passed through a tibial tunnel in a bovine tibia, looped around a rigid cross‐pin, and fixed to the tibia with a Washerloc fixation device. The grafts were cyclically loaded for 225,000 cycles from 20 to 170 N. Prior to and at intervals during the cyclic loading, simultaneous radiographs were taken of the tibia and graft. RSA was used to determine the 3‐dimensional coordinates of the markers from which the lengthening in each region was computed at each interval. The regions of the tibial and femoral fixations were the largest contributors to the increase in length of the graft, with maximum average values of 0.91 and 0.76 mm respectively after 225,000 cycles. The region between the fixations contributed least to lengthening of the graft, with a maximum average value of 0.23 mm. More than 90% of the lengthening in each region occurred before 100,000 cycles of loading. RSA proved to be a useful method for measuring lengthening in all three regions of the graft construct. Lengthening of the graft construct in both regions of fixation is sufficiently large that the combined contributions may cause a recurrence of instability in some knees. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Targeting of EWS/FLI‐1 by RNA interference attenuates the tumor phenotype of Ewing's sarcoma cells in vitro
Authors: Chansky Howard A. , Barahmand‐pour Fariba , Mei Qi , Kahn‐Farooqi Waqqar , Zielinska‐Kwiatkowska Anna , Blackburn Michael , Chansky Kari , Conrad Ernest U. , Bruckner James D. , Greenlee Theodore K. , Yang Liu
Published: January 2004

The defining cytogenetic abnormality of Ewing's sarcoma is the presence of a balanced t(11;22) translocation expressing the EWS/FLI‐1 chimeric fusion protein. The effect of EWS/FLI‐1 appears to be dominant negative since over‐expression of EWS does not overcome the sarcoma phenotype. Previous studies have shown that EWS/FLI‐1 as well as related sarcoma fusion proteins are necessary and sufficient to induce transformation both in vitro and in vivo. In this study we report that synthetic small interfering RNA (siRNA) specifically suppresses EWS/FLI‐1 fusion gene expression in SK‐ES Ewing's sarcoma cells. Knockdown of the EWS/FLI‐1 fusion protein is correlated with decreased cell proliferation and increased apoptosis. We demonstrate that Ewing's sarcoma tumors as well as Ewing's sarcoma cell lines predominantly express the CXCR4 chemokine receptor. Using an in vitro invasion assay, the SDF‐1 ligand of CXCR4 was shown to be a potent stimulus of invasion by SK‐ES cells. Knockdown of EWS/FLI‐1 by RNA interference abrogates the invasiveness of SK‐ES cells. These experiments suggest that targeted silencing of the EWS/FLI‐1 fusion gene by siRNA represents a promising strategy to study the loss of EWS/FLI‐1 protein in Ewing's sarcoma cells of otherwise identical genetic background. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Fractional cointegration and real exchange rates
Authors: Caporale Guglielmo Maria , Gil‐Alana Luis A.
Published: January 2004

This paper uses fractional integration and cointegration to model the DM–US dollar and the yen–US dollar real exchange rates in terms of both monetary and real factors, more specifically real interest rate and labour productivity differentials. We find that whilst the individual series may be integrated of order 1, their long‐run relationship might have a fractionally cointegrated structure. This means that mean reversion occurs, consistently with the findings of other studies. However, it also indicates, in contrast to such studies, that the cointegrating relationship possesses long memory. In other words, the error correction term responds slowly to shocks, implying that deviations from equilibrium are long‐lived. It appears that only a combination of real and monetary variables can accurately track down the movements of real exchange rates.
A 750-yr record of autumn snowfall and temperature variability and winter storminess recorded in the varved sediments of Bear Lake, Devon Island, Arctic Canada
Authors: Lamoureux Scott F. , Gilbert Robert
Published: January 2004

The varve record from High Arctic, proglacial Bear Lake reveals a regionally coherent hydroclimatic signal as well as complexities due to changing hydroclimatic and limnologic conditions. Varve formation is strongly dependent on underflows that exhibit variability in strength during the past 750 yr. Periods with reduced underflow sedimentation and accumulation rates fail to produce varves in the distal part of the lake. Isolated coarse silt and sand grains occur in 80% of the varves and are interpreted to be niveo-aeolian in origin. Coarse (>500 μm) sand grains deposited on the lake ice by strong winter winds are notably less common since A.D. 1850, likely due to reduced storminess. Regression of the varve thickness record with meteorological records indicates high correlations with autumn (September and October) temperatures and total monthly snowfall. These correlations are best at times when underflow activity is sufficiently strong to produce varves throughout the lake. The close association with warmer temperatures and snow-bearing synoptic systems moving north in Baffin Bay suggests that the primary climate signal in the varves is varying autumn snow pack that controls nival discharge in the following year. The similarity between the other records of melt season temperature and sea-ice cover and the Bear Lake record suggests that summer and autumn conditions were generally similar across the Baffin Bay region through much of the last millennium.
Volume‐regulated Cl− channels in human pleural mesothelioma cells
Authors: Meyer Giuliano , Rodighiero Simona , Guizzardi Fabiana , Bazzini Claudia , Bottà Guido , Bertocchi Cristina , Garavaglia Lisa , Dossena Silvia , Manfredi Rosangela , Sironi Chiara , Catania Anna , Paulmichl Markus
Published: January 2004

Anion channels in human mesothelial and mesothelioma cell lines were characterized by patch‐clamp and biomolecular approaches. We found an outwardly rectifying anionic current which was inactivated at positive voltages and inhibited by extracellular adenosine 5′‐triphosphate (ATP). Mesothelial and mesothelioma cells behaved differently concerning current inactivation properties. Inactivation is more pronounced and has a steeper onset in mesothelial cells. Different reversal potentials, in asymmetrical Cl− solutions, that could be attributed to a different selectivity of the channel, have been observed in the two cell lines. Mesothelioma cell single‐channel analysis indicates that the number of the same active anion channel (3–4 pS) increased under hypoosmotic conditions. Immunocytochemistry experiments showed the presence of ICln protein in the cytosol and in the plasma membrane. Western blot analysis revealed an increase of ICln in the membrane under hypotonic conditions, an event possibly related to the activation of Cl− channels.
Autocrine release of TGF‐β by portal fibroblasts regulates cell growth
Authors: Wells Rebecca G , Kruglov Emma , Dranoff Jonathan A
Published: January 2004

Portal fibroblasts (PF) are a newly isolated population of fibrogenic cells in the liver postulated to play a significant role in early biliary fibrosis. Because transforming growth factor‐β (TGF)‐β is a key growth factor in fibrosis, we characterized the response of PF to TGF‐β. We demonstrate that PF produce significant amounts of TGF‐β2 and, unlike activated hepatic stellate cells (HSC), express all three TGF‐β receptors and are growth inhibited by TGF‐β1 and TGF‐β2. Fibroblast growth factor (FGF)‐2, but not platelet derived growth factor (PDGF), causes PF proliferation. These data suggest a mechanism whereby HSC eclipse PF as the dominant myofibroblast population in biliary fibrosis.
Expression regulation of the yeast PDR5 ATP‐binding cassette (ABC) transporter suggests a role in cellular detoxification during the exponential growth phase
Authors: Mamnun Yasmine M. , Schüller Christoph , Kuchler Karl
Published: January 2004

The yeast ATP‐binding cassette transporter Pdr5p mediates pleiotropic drug resistance (PDR) by effluxing a variety of xenobiotics. Immunoblotting demonstrates that Pdr5p levels are high in the logarithmic growth phase, while its levels decrease sharply when cells exit exponential growth. Here, we show that PDR5 promoter activity is dramatically reduced when cells stop growing due to a limitation of glucose or nitrogen or when they approach stationary phase. Interestingly, Pdr3p, a major transcriptional regulator of PDR5, shows the same regulatory pattern. Feeding glucose to starved cells rapidly re‐induces both PDR5 and PDR3 transcription. Importantly, diminished Pdr5p levels, as present after starvation, are rapidly restored in response to xenobiotic challenges that activate the transcription factors Pdr1p and Pdr3p. Our data indicate a role for yeast Pdr5p in cellular detoxification during exponential growth.
Detergents as tools for the purification and classification of lipid rafts
Authors: Chamberlain Luke H
Published: January 2004

The relative insolubility of lipid rafts in cold non‐ionic detergents is the most widely used method to purify these fascinating membrane domains from intact cells or membranes. Most of what we know about lipid raft function has been derived from experiments utilising detergent insolubility as the basis for raft purification. Recently, a wider range of detergents have been used to purify ‘rafts’, and rafts have been subclassified based on their differential solubility in different detergents. This minireview critically examines the use of detergents as tools for raft isolation and for the subclassification of rafts.
Functional proteomics of circadian expressed proteins from Chlamydomonas reinhardtii
Authors: Wagner Volker , Fiedler Monika , Markert Christine , Hippler Michael , Mittag Maria
Published: January 2004

In this study, functional proteomics was successfully applied for the characterization of circadian expressed, basic proteins. For this purpose, we have chosen the green model alga Chlamydomonas reinhardtii since its entire nuclear genome is available and it is ideally suited for biochemical enrichment procedures. Proteins from cells harvested during subjective day and night were heparin affinity purified. They were separated by two‐dimensional gel electrophoresis suited for basic proteins and analyzed after tryptic digestion by electrospray ionization mass spectrometry. We can show for the first time that the expressions of a protein disulfide isomerase‐like protein and a tetratricopeptide repeat protein change in a circadian manner. Interestingly, both proteins are known to be interaction partners in multiprotein complexes including RNA binding proteins.
A model of Io's local electric field for a combined Alfvénic and unipolar inductor far‐field coupling
Authors: Saur Joachim
Published: January 2004

In this paper we develop an equation for Io's electric field/electric potential which includes Io's inhomogeneous and anisotropic conductances and treats Io's far‐field interaction in both limits: the unipolar inductor and the Alfvén wing models. We solve this equation for constant conductances within an elliptically shaped Ionian ionosphere, which leads to useful analytic expressions for properties of Io's local interaction, specifically, the total electric current driven by Io's interaction. Several previous calculations underestimated the total electric current by a factor of two. Oversimplifications of the Alfvénic current system might be one of the reasons. Our expressions also show that it is not the voltage across Io's ionosphere, as often assumed, that is physically related to the electric current; but it is the electric field and the extensions of the ionosphere in both directions. We show in addition that the Alfvénic and unipolar inductor models lead to different properties of Io's local interaction, e.g., the maximum plasma speed up around Io is higher in the Alfvénic coupling case.
Ionospheric electric potentials for substorms calculated from a solar wind‐magnetosphere MHD simulation and a magnetogram inversion technique
Authors: Nakata H. , Shinohara M. , Kamide Y. , Ogino T.
Published: January 2004

The electric potentials for substorms are calculated from the three‐dimensional MHD simulation for solar wind‐magnetosphere coupling developed by Ogino [1986], combined with the average conductivity maps in the ionosphere used in the work of Kamide et al. [1996]. For this combination, an electrostatic model of the ionospheric electric potentials is utilized, i.e., j∥ = ∇ · (Σ · ∇Φ), where j∥ is field‐aligned current, Σ is ionospheric conductivity tensor, and Φ is ionospheric electric potential. The ionospheric potentials for the different phases of substorms are calculated through mapping field‐aligned currents from the global MHD simulation onto the polar ionosphere. Comparing the present results with Kamide et al. [1996], it is found that the realistic potential patterns for the growth and expansion phases of substorms can be obtained by the present electrostatic model. Owing to the lack of the magnetosphere‐ionosphere coupling mechanism in the present study, however, the simulated ionospheric potential appears to be unrealistic for the peak of substorms. Although substorms are generated by north‐to‐south turnings of IMF in this model, the electric potentials for substorms are found to be affected only by southward IMF. It is also shown that the cross‐polar cap potential drops are highly correlated with the interplanetary electric field for the growth and expansion phases of substorms. While the potential drops are also found to correlate well with the solar wind density, this positive correlation is opposite to what theoretical studies indicate. This is because the intensity of the field‐aligned currents originating from the magnetopause, which is proportional to the electric potential, increases with the solar wind density in the simulation.
TOMEX: Mesospheric and lower thermospheric diffusivities and instability layers
Authors: Bishop R. L. , Larsen M. F. , Hecht J. H. , Liu A. Z. , Gardner C. S.
Published: January 2004

The Turbulent Oxygen Mixing Experiment (TOMEX), which was carried out at White Sands Missile Range in New Mexico on 26 October 2000, included a rocketborne trimethyl aluminum (TMA) chemical tracer experiment. The subsequent TMA trails provided detailed information about the horizontal neutral wind, turbulence, and diffusivity properties of the atmosphere between approximately 85 and 140 km altitude. Measurements with the University of Illinois Na wind/temperature lidar located at the Starfire Optical Range, NM, provided a detailed time history of the stability properties between 85 and 105‐km altitude, including high‐resolution wind and temperature measurements prior to and during the chemical tracer measurements. The diffusivities estimated from the trail expansion rates have values consistent with the values expected for molecular diffusion above 110‐km altitude and values that are larger than those for molecular diffusion at most altitudes below. Below 103 km, both regions of dynamic and convective instability were found, and the diffusivities are strongly controlled by the instabilities. The unstable regions are well mixed, but the intermediate regions, in some cases, have very small eddy energy dissipation rates. The nearly instantaneous measurements also suggest that eddy diffusion is still important in the height range between 103 km, the nominal turbopause height, and 110 km.
Application of ionospheric topside‐sounding results to magnetospheric physics and astrophysics
Authors: Benson Robert F. , Osherovich Vladimir A.
Published: January 2004

A brief review is presented to illustrate how the knowledge and experience gained from investigations of ionospheric topside‐sounder ionograms has benefited scientific research beyond the ionosphere. In particular, to the interpretation of (1) natural radio emissions from space plasmas, (2) sounder‐stimulated echoes and plasma emissions, and plasma diagnostics in planetary magnetospheres and (3) X‐ray spectra of disks around neutron stars and black holes. The relevant data are from 60 satellite years of ionospheric topside‐sounder operations by the four satellites of the International Satellites for Ionospheric Studies (ISIS) program from 1963 through 1989. Not all of these data were reduced to ionograms on 35‐mm film. An ongoing effort at the NASA Goddard Space Flight Center is producing digital topside‐sounder ionograms directly from a selected subset of the original telemetry tapes. More than 300,000 digital ionograms are now in the National Space Science Data Center at the NASA GSFC (http://nssdc.gsfc.nasa.gov/space/isis/isis-status.html).
Subduction Factory 3: An Excel worksheet and macro for calculating the densities, seismic wave speeds, and H2O contents of minerals and rocks at pressure and temperature
Authors: Hacker Bradley R. , Abers Geoffrey A.
Published: January 2004

An Excel macro to calculate mineral and rock physical properties at elevated pressure and temperature is presented. The workbook includes an expandable database of physical parameters for 52 rock‐forming minerals stable at high pressures and temperatures. For these minerals the elastic moduli, densities, seismic velocities, and H2O contents are calculated at any specified P and T conditions, using basic thermodynamic relationships and third‐order finite strain theory. The mineral modes of suites of rocks are also specifiable, so that their predicted aggregate properties can be calculated using standard solid mixing theories. A suite of sample rock modes taken from the literature provides a useful starting point. The results of these calculations can be applied to a wide variety of geophysical questions including estimating the alteration of the oceanic crust and mantle; predicting the seismic velocities of lower‐crustal xenoliths; estimating the effects of changes in mineralogy, pressure and temperature on buoyancy; and assessing the H2O content and mineralogy of subducted lithosphere from seismic observations.
The role of the western Pacific in decadal variability
Authors: Yu B. , Boer G. J.
Published: January 2004

Recent observational studies indicate that the mechanisms of Pacific decadal variability importantly involve the tropical Indian/western Pacific oceans and south Pacific convergence zone. Evidence for this suggestion is sought from the results of a 1000‐year integration with the CCCma coupled ocean‐atmosphere model which reasonably successfully simulates the principal mode of Pacific decadal‐interdecadal variability. Both the western North Pacific, where ocean dynamics act to generate heat content anomalies, and the western South Pacific, where surface heat flux forcing acts to generate heat content anomalies, play a role. These heat content anomalies are advected to and eastward along the equator providing the negative feedback to allow the system to change phase.
Case studies of the dynamics of ionospheric ions in the Earth's magnetotail
Authors: Sauvaud J.‐A. , Louarn P. , Fruit G. , Stenuit H. , Vallat C. , Dandouras J. , Rème H. , André M. , Balogh A. , Dunlop M. , Kistler L. , Möbius E. , Mouikis C. , Klecker B. , Parks G. K. , McFadden J. , Carlson C. , Marcucci F. , Pallocchia G. , Lundin R. , Korth A. , McCarthy M.
Published: January 2004

This paper presents case studies of the dynamics of the terrestrial ions in the midplasma sheet and inside the lobes (∼17–19 RE). The high time resolution measurements of H+, He+, and O+ ions made on board Cluster show that these ions are massively injected into the tail during substorms/storms from the nightside ionosphere and mainly dispersed by time of flight effects; a single oxygen injection being able to account for over 80% of the oxygen population of the midtail plasma sheet during storm time. Inside the lobes, during disturbed times, ionospheric oxygen ions appear as nearly monoenergetic beams, quasi field‐aligned, propagating antisunward from the ionosphere, as expected from the “cleft ion fountain.” Most of the time, the ionospheric protons are very cold and their distribution function is not fully measurable by a charged spacecraft. However, we show that protons can, at times, acquire a large drift motion, reach energy larger than 30 eV, and be directly measurable by the CIS spectrometers. This occurs when large disturbances propagate in the plasma sheet boundary layer during both quiet and disturbed periods. We show that the large, variable, Alfvén waves generated by these plasma sheet disturbances modulate the energy of lobe protons and oxygen ions and inject electromagnetic energy, in excess of 15 × 10−3 W/m2, down to the polar cap. Deeper inside the plasma sheet boundary layer, large electric fields associated with the Earthward stream of plasma sheet particles give enough drift energy to a very cold ionospheric proton population to become fully detectable by the Cluster ion spectrometers.
Relationship between solar wind low‐energy energetic ion enhancements and large geomagnetic storms
Authors: Smith Z. , Murtagh W. , Smithtro C.
Published: January 2004

It is well established that energetic ion enhancements (an energetic ion enhancement will hereafter be referred to as an EIE) are partly due to acceleration by interplanetary shocks as the shocks propagate towards Earth and that arrivals of these shocks at Earth are well associated with geomagnetic storms. The observation of EIEs at satellites located at L1 is a potential tool for predicting the arrival of interplanetary shocks hours before they arrive at L1. Following an earlier study using WIND satellite data [Smith and Zwickl, 1999], we evaluate the potential of EIEs for forecasting geomagnetic storms during the period of February 1998 through December 2000. Since there are many more EIEs than large geomagnetic storms, additional associations that might improve the identification of precursors of large storms were investigated. These included probable solar sources, accompanying interplanetary shocks, and the shocks' interplanetary drivers. Solar images and data from the Advanced Composition Explorer (ACE) and WIND satellites were used. The Potsdam Kp was used to specify geomagnetic storm severity. Almost all large geomagnetic storms (Kp ≥ 7) in this time period were preceded by EIEs that were associated with shocks driven by transient interplanetary disturbances. The converse is not true. Although most transient‐associated EIEs were followed by some geomagnetic activity, there is a large span in the response. Most (95%) of EIEs with maximum flux ≥1.105 pfu were followed by activity with Kp > 4 and 80% by storms with Kp ≥ 5. For a threshold of 3.105 pfu, 67% of the large storms would be identified, 89% of the EIEs were followed by storms with Kp ≥ 5, and 53% by large storms (Kp ≥ 7). Using the additional information on the interplanetary drivers results in an increase in the correctly predicted events from 53% to 61%. For a threshold of 1.106 pfu, all (100%) EIEs were followed by storms with Kp ≥ 5, 76% of the events were correctly predicted but 16 of the 30 large storms were missed. Most of the EIEs were followed by significant periods of southward Bz and in close to 70% of the EIEs, the Bz following the EIE was first northward before turning southward. We also investigated the relationship of the EIEs to halo or partial‐halo coronal mass ejections (CMEs), and found that EIE events associated with halo CMEs are more likely to be followed by a large geomagnetic storm, but a lack of halo or partial‐halo CME association does not preclude the occurrence of a large geomagnetic storm.
IMAGES‐SCAPE2: A modeling study of size‐ and chemically resolved aerosol thermodynamics in a global chemical transport model
Authors: Rodriguez Marco A. , Dabdub Donald
Published: January 2004

Chemically and size‐resolved aerosol mass size distributions are simulated online using the Intermediate Model of Global Evolution of Species (IMAGES). Aerosol‐phase thermodynamics is coupled to this chemical transport model using the Simulating Composition of Atmospheric Particles at Equilibrium (SCAPE2) module. Emphasis is placed on the equilibrium concentrations of aerosol ammonium, nitrate, sulfate, and water content subject to the interaction with ions from sea salt and dust. Transport for both aerosol and gas‐phase species is solved using a semi‐Lagrangian scheme driven by monthly mean climatological variables provided by European Centre for Medium‐Range Weather Forecasts (ECMWF) analysis. This study presents estimates of annual average dry mass size distributions at selected stations in North America and Europe. Simulations are performed to observe the major differences between the coupled IMAGES‐SCAPE2 model and IMAGES alone for key aerosol species. Nitrate concentrations predicted with IMAGES‐SCAPE2 compare better with observations than those calculated with IMAGES alone. Model results show that aerosol size distributions are generally bimodal. This study finds that over polluted continental regions, the presence of sea‐salt and dust aerosol potentially increases the formation of sulfate by 20–80%. Nitrate formation is enhanced by 14–60%, whereas ammonium formation is decreased by 20–60%. Nitrate plays an important role to determine the size distributions in many European stations. The presence of water changes the general shape of the size distribution, placing maximum values on larger size ranges.
Spectral analysis of boundary layer ozone data from the EUROTRAC TOR network
Authors: Cvitaš T. , Furger M. , Girgzdiene R. , Haszpra L. , Kezele N. , Klasinc L. , Planinšek A. , Pompe M. , Prevot A. S. H. , Scheel H. E. , Schuepbach E.
Published: January 2004

Data obtained during many years of continuous ozone monitoring at 12 selected EUROTRAC‐TOR (Eureka environmental project: European experiment on Transport and transformation of environmentally relevant trace Constituents in the troposphere over Europe, subproject Tropospheric Ozone Research) network stations were analyzed by applying Fourier transformation (FT). FT averaged over the years, autocorrelation functions and FT of such functions were calculated for each site. As expected, strong frequency signals are found for the 1 year and 1 day periods. The relative intensity of the 1 day peak can be correlated with the intensity of local photochemical pollution as represented by a photochemical pollution index. A collective FT spectrum for seven European stations was calculated. This comparison confirms the existence of a common variation in ozone volume fractions with quasi‐periods ranging between 7 and 44 days. These frequencies are most probably connected with quasi‐cyclic synoptic scale meteorological influences. A comparison of meteorological data from the station Zugspitze showed similar periodicities.
Interferon alfa2a induction therapy in combination with ribavirin and amantadine for the treatment of naive patients with chronic HCV infection
Authors: Engler S. , Flechtenmacher C. , Wiedemann K. H. , Gugler R. , Stremmel W. , Kallinowski B.
Published: January 2004

Summary.  Pilot studies have suggested that the addition of amantadine to interferon (IFN) is effective against hepatitis C virus (HCV). Furthermore, IFN induction therapy seems to improve virological response rates. In this open, randomized, multicentre trial we compared safety and efficacy of a triple therapy comprising IFNα2a, ribavirin and amantadine using high induction doses (6 MU IFNα daily for the first 6 weeks) against a therapy with standard IFNα dosages over the entire treatment period plus amantadine and ribavirin. A total of 158 naive patients with chronic HCV infection were randomized 1:1. Group A (n = 81): induction therapy with 6 MU IFNα daily for 6 weeks, followed by 6 MU three times a week (tiw) for 18 weeks and then 3 MU tiw until week 48. Group B (n = 77): standard therapy with 6 MU IFNα tiw for 24 weeks, followed by 3 MU until week 48. All patients received oral ribavirin (10 mg/kg/day) and amantadine (200 mg/day). The triple therapy was safe and well tolerated. There were no significant differences between the groups with respect to biochemical response rates. Groups A and B did not differ in virological response rates at the end of treatment (33%vs 35%) or at the end of the 6 month follow up period (37%vs 39%). We could not detect favourable effects on sustained virological response rates using induction therapy, in either genotype 1 or non‐1 infected patients. In summary, induction therapy with 6 MU IFNα daily did not result in increased overall response rates compared with standard IFNα dosages of 6 MU tiw.
Thymosin‐α 1 plus interferon‐α for naive patients with chronic hepatitis C: results of a randomized controlled pilot trial
Authors: Andreone P. , Gramenzi A. , Cursaro C. , Felline F. , Loggi E. , D'Errico A. , Spinosa M. , Lorenzini S. , Biselli M. , Bernardi M.
Published: January 2004

Summary.  In this pilot study, we evaluated the efficacy of interferon‐α (IFN) plus Thymosin‐α 1 (TA1) to that of IFN alone in naive patients with chronic hepatitis C. Twenty‐two patients were randomized to receive interferon‐α2b (3 million units three times a week) plus thymosin‐α l (900 μg/m2 body surface area) and 19 received interferon‐α2b alone at the same dose. Patients were treated for 6 months and followed up for another 6 months. Biochemical (alanine aminotransferase values) and virological (hepatitis C virus‐RNA) responses to treatment were determined. Combination treatment showed significantly higher efficacy than monotherapy in achieving virological end‐of‐treatment response (P = 0.03). At 6‐month follow up, the sustained biochemical and virological response was not different between the two groups. Our results indicate that the immune modulator TA1 may enhance the end‐of‐treatment response in naive patients with chronic hepatitis C. Higher doses and/ore more prolonged courses as well as the association with new interferon formulation such as pegylated interferons could improve the sustained response rates to this treatment.