bluuebunny/crossref_metadata_2025 huggingface dataset:
Vitamin K‐dependent coagulation factors and fibrinogen levels in FFP remain stable upon repeated freezing and thawing
Authors: Ben‐Tal Ofira , Zwang Ety , Eichel Roza , Badalbev Tanya , Hareuveni Mara
Published: June 2003

BACKGROUND: FFP is considered adequate for transfusion up to 24 hours after thawing and is currently used most often to replace deficient clotting factors, such as in warfarin overdose. We set to examine the levels of vitamin K‐dependent factors (i.e., prothrombin, FVII, F IX, FX), as well as fibrinogen, upon twice freezing and thawing of FFP. If factor levels in refrozen FFP remain within normal limits, this component can possibly be transfused, thus avoiding wastage of precious blood components.

STUDY DESIGN AND METHODS: Twenty units of FFP, five units of each blood group A, B, AB, and O, were thawed, and aliquots were taken for measurement of coagulation factors. The plasma units were then kept for 24 hours at 4°C, at which point a second aliquot was taken, The remaining FFP units were refrozen and kept at –80°C for 1 week. The above procedure was then repeated. Coagulation‐factor activity and fibrinogen level were measured by the coagulation analyzer.

RESULTS: The mean levels of prothrombin, FVII, F IX, FX, and fibrinogen of each blood group (A, B, AB, and O) were calculated for each of four time points and found not statistically different (p > 0.05). Therefore, the rest of the analysis was done for all 20 FFP units as one group. The mean ± SD levels of each coagulation factor at each time point demonstrated that all levels were within normal limits of all factors measured and that for none of the factors was there a significant decay of activity.

CONCLUSIONS: The levels of prothrombin, FVII, F IX, FX, and fibrinogen remain stable and adequate for transfusion in twice‐thawed‐and‐refrozen FFP. This component can be safely used for transfusion as a source of vitamin K‐dependent clotting factors and fibrinogen.
Vector hysteresis model based on neural network
Authors: Kuczmann Miklós , Iványi Amália
Published: June 2003

On the basis of the Kolmogorov‐Arnold theory, the feedforward type artificial neural networks (NNs) are able to approximate any kind of nonlinear, continuous functions represented by its discrete set of measurements. A NN‐based scalar hysteresis model has been constructed preliminarily on the function approximation ability of NNs. An if‐then type knowledge‐base represents the properties of the hysteresis characteristics. Vectorial generalization to describe isotropic and anisotropic magnetic materials in two and three dimensions with an original identification method has been introduced in this paper.
Course of low back pain among nurses: a longitudinal study across eight years
Authors: Maul I , Läubli T , Klipstein A , Krueger H
Published: June 2003

Aims:To describe the course of low back pain (LBP) among nurses across eight years.

Methods:A longitudinal study was performed with a follow up at 1 and 8 years among nurses employed by a large university hospital in Switzerland. A modified version of the Nordic Questionnaire was distributed to obtain information about demographic data, occupational activities, and various aspects of LBP. A clinical examination and several functional tests were used to overcome the problems associated with subjective pain reporting. Nurses having answered the questionnaire on all three occasions (n = 269) were classified into subgroups according to their pain intensity. For each subgroup the course of LBP was recorded.

Results:LBP was highly prevalent with an annual prevalence varying from 73% to 76%. A large percentage (38%) indicated the same intensity of LBP on all three occasions. The proportion of nurses reporting repeated increase of LBP (19%) was approximately as large as the proportion who complained about repeated decrease of LBP (17%).

Conclusion:It became evident that LBP poses a persistent problem among nurses. Over an eight year period almost half of the nurses indicated the same intensity of LBP, thus supporting a recurrent rather than a progressive nature of LBP.
Investigation of the Thermodynamic Properties of Anharmonic Crystals with Defects and Influence of Anharmonicity in Exafs by the Moment Method
Authors: Hung Vu Van , Hai Nguyen Thanh
Published: June 2003

By the moment method established previously on the basis of the statistical mechanics, the thermodynamic properties of a strongly anharmonic face-centered and body-centered cubic crystal with point defect are considered. The thermal expansion coefficient, the specific heat Cv and Cp, the isothermal and adiabatic compressibility, etc. are calculated. Our calculated results of the thermal expansion coefficient, the specific heat Cv and Cp… of W, Nb, Au and Ag metals at various temperatures agrees well with the measured values. The anharmonic effects in extended X-ray absorption fine structure (EXAFS) in the single-shell model are considered. We have obtained a new formula for anharmonic contribution to the mean square relative displacement. The anharmonicity is proportional to the temperature and enters the phase change of EXAFS. Our calculated results of Debye–Waller factor and phase change in EXAFS of Cu at various temperatures agrees well with the measured values.
Artificial Atoms in Magnetic Field: Electronic and Optical Properties
Authors: Rinaldi R.
Published: June 2003

Quantum dots semiconductor heterostructures exhibit optical and electronic properties similar to those of real atoms, due to the delta like dispersion of the density of states. The study of the optical and electronic properties of artificial atoms in high magnetic fields allows the observation of quantum effects typical of the atomic physics. In this work we review the problem of artificial atoms in magnetic fields starting from the single-particle theory up to the problems encountered in the observation of correlation effects when two or more carriers are confined in the dot. The main experiments elucidating the change of the optical and electronic properties of artifical atoms in magnetic fields are also reviewed.
Design of Gates for Quantum Computation: The Three-Spin XOR Gate in Terms of Two-Spin Interactions
Authors: Mozyrsky Dima , Privman Vladimir , Hotaling Steven P.
Published: June 2003

We propose to design multispin quantum gates in which the input and output two-state systems (spins) are not necessarily identical. We describe the motivations for such studies and then derive an explicit general two-spin interaction Hamiltonian which accomplishes the quantum XOR gate function for a system of three spins: two input and one output.
Why Two Renormalization Groups are Better Than One
Authors: Stephens C. R.
Published: June 2003

The advantages of using more than one renormalization group (RG) in problems with more than one important length scale are discussed. It is shown that:

i) using different RG's can lead to complementary information, i.e. what is very difficult to calculate with an RG based on one flow parameter may be much more accesible using another;

ii) using more than one RG requires less physical input in order to describe via RG methods the theory as a function of its parameters;

iii) using more than one RG allows one to describe problems with more than one diverging length scale.

The above points are illustrated concretely in the context of both particle physics and statistical physics using the techniques of environmentally friendly renormalization. Specifically, finite temperature λφ4 theory, an Ising-type system in a film geometry, an Ising-type system in a transverse magnetic field, the QCD coupling constant at finite temperature and the crossover between bulk and surface critical behavior in a semi-infinite system are considered.
Antworten auf: ’Zur Entstellung C.G. Jungs unter Post-Jungianern‘ von Manfred Krapp
Authors: Höhfeld Kurt , Springer Anne , von der Tann Matthias
Published: June 2003

Der Konflikt zwischen Tiefenpsychologie und Theologie kann gelöst werden, wenn man die Bewusstseinsevolution betrachtet. Dann erweist er sich als Folge der Bewusstseinsmutation: jener erkenntnistheoretischen Revolution, bei der im Verlauf der Neuzeit die archaische Weltsicht, aus der die Theologie hervorging, überwunden und durch eine fundamental neue abgelöst worden ist.
Effects of Cataractogenesis on the CDP-Choline Pathway: Changes in ATP Concentration and Phosphocholine Synthesis during and after Exposure of Rat Lenses to Sugars in vitro and in vivo
Authors: Liu Ying , Blum Penny S. , Pabst Diana M. , Chakrabarti Ipsit , Jernigan Jr. H.M.
Published: June 2003

We measured choline influx and phosphorylation, ATP concentration ([ATP]), choline kinase activity and lens swelling during formation and partial reversal of sugar cataracts in rat lenses incubated with xylose or galactose and in lenses of galactosemic rats. [ATP] and phosphocholine (P-Cho) synthesis decreased about 60 and 40% after 4 h in normal rat lenses incubated up to 24 h in medium containing 30 mM xylose and partially recovered when the lenses were then removed from the xylose. Incubation with the somewhat less cataractogenic sugar galactose decreased P-Cho synthesis but had little effect on [ATP]. P-Cho synthesis decreased rapidly in the lenses of rats fed a 50% galactose diet, but began recovery by the third day on this diet. [ATP] decreased for at least 10 days during the galactose diet and did not recover, even with resumption of the control diet (50% starch) after 4 or 7 days. The results of in vitro and in vivo sugar cataractogenesis differed from each other in several respects, including effects on choline influx and the degree to which the changes were reversible. The in vitro and in vivo sugar cataracts, however, could both produce swelling and opacification of the lens and decreased P-Cho synthesis and [ATP]. Neither model caused a substantial change in the choline kinase activity (as measured in cell-free assays). The data did not generally support the hypothesis that decreased [ATP] causes decreased P-Cho synthesis.
The CERES S'COOL Project
Authors: Chambers Lin H. , Young David F. , Costulis P. Kay , Detweiler Pauline T. , Fischer Joyce D. , Sepulveda Roberto , Stoddard Douglas B. , Falcone Amanda
Published: June 2003

In recent years, an education plan has been a required part of most proposals for new scientific research funding from NASA. Likewise, the National Science Foundation considers “integration of research and education” as one of its principal strategies. As a result, many scientists are seeking effective ways to incorporate education into their work. This article shares important lessons learned by one group of scientists embarking on outreach efforts. Experience with the Students' Cloud Observations On-line (S'COOL) Project, the educational outreach portion of the Clouds and the Earth's Radiant Energy System (CERES) investigation, yields lessons that may help other scientists to develop useful outreach efforts.

CERES scientists developed S'COOL over a 15-month period, with direct involvement and feedback from teachers. S'COOL has continued to evolve, thanks to ongoing feedback from participants. As a result, the project has been quite successful, currently involving over 1400 registered participants in 61 countries around the world. Student reports of cloud conditions help scientists verify their cloud property retrieval algorithms and allow students to obtain and analyze real scientific data. A number of educational materials, including an extensive multilingual Web site, have been developed to help teachers and students understand the research questions and the challenges of working with global remote-sensing datasets.
The Advanced Very High Resolution Radiometer Pathfinder Atmosphere (PATMOS) Climate Dataset: A Resource for Climate Research
Authors: Jacobowitz Herbert , Stowe Larry L. , Ohring George , Heidinger Andrew , Knapp Kenneth , Nalli Nicholas R.
Published: June 2003

As part of the joint National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) Pathfinder program, the NOAA National Environmental Satellite, Data, and Information Service (NESDIS) has created a research-quality global atmospheric dataset through the reprocessing of Advanced Very High Resolution Radiometer (AVHRR) observations since 1981. The AVHRR is an imaging radiometer that flies on NOAA polar-orbiting operational environmental satellites (POES) measuring radiation reflected and emitted by the earth in five spectral channels. Raw AVHRR observations were recalibrated using a vicarious calibration technique for the reflectance channels and an appropriate treatment of the nonlinearity of the infrared channels. The observations are analyzed in the Pathfinder Atmosphere (PATMOS) project to obtain statistics of channel radiances, cloud amount, top of the atmosphere radiation budget, and aerosol optical thickness over ocean. The radiances and radiation budget components are determined for clear-sky and all-sky conditions. The output products are generated on a quasi-equalarea grid with an approximate 110 km × 110 km spatial resolution and twice-a-day temporal resolution, and averaged over 5-day (pentad) and monthly time periods. PATMOS data span the period from September 1981 through June 2001. Analyses show that the PATMOS data in their current archived form are sufficiently accurate for studies of the interaction of clouds and aerosol with solar and terrestrial radiation, and of climatic phenomena with large signals (e.g., the annual cycle, monsoons, ENSOs, or major volcanic eruptions). Global maps of the annual average of selected products are displayed to illustrate the capability of the dataset to depict the climatological fields and the spatial detail and relationships between the fields, further demonstrating how PATMOS is a unique resource for climate studies. Smaller climate signals, such as those associated with global warming, may be more difficult to detect due to the presence of artifacts in the time series of the products. Principally, these are caused by the drift of each satellite's observation time over its mission. A statistical method, which removes most of these artifacts, is briefly discussed. Quality of the products is assessed by comparing the adjusted monthly mean time series for each product with those derived from independent satellite observations. The PATMOS dataset for the monthly means is accessible at www.saa.noaa.gov/.
Changes in the interfacial properties of PC/SAN blends with compatibilizer
Authors: Kim J. H. , Kim C. K.
Published: June 2003

Block copolymers of polycarbonate‐b‐poly(methyl methacrylate) (PC‐b‐PMMA) and tetramethyl poly(carbonate)‐b‐poly(methyl methacrylate) (TMPC‐b‐PMMA) were examined as compatibilizers for blends of polycarbonate (PC) with styrene‐co‐acrylonitrile (SAN) copolymer. To explore the effects of block copolymers on the compatibility of PC/SAN blends, the average diameter of the dispersed particles in the blend was measured with an image analyzer, and the interfacial properties of the blends were analyzed with an imbedded fiber retraction (IFR) technique and an asymmetric double cantilever beam fracture test. The average diameter of dispersed particles and interfacial tension of the PC/SAN blends were reduced by adding compatibilizer to the PC/SAN blends. Fracture toughness of the blends was also improved by enhancing interfacial adhesion with compatibilizer. TMPC‐b‐PMMA copolymer was more effective than PC‐b‐PMMA copolymer as a compatibilizer for the PC/SAN blends. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2649–2656, 2003
Microbial detection, surface morphology, and thermal stability of cotton and cotton/polyester fabrics treated with antimicrobial formulations by a radiation method
Authors: Zohdy M. H. , Abdel Kareem H. , El‐Naggar A. M. , Hassan M. S.
Published: June 2003

Cotton and cotton/polyester fabrics were treated with a proposed antimicrobial formulation based on zinc oxide (ZnO), Impron MTP (binder), and Setamol WS (dispersing agent) under the effect of γ irradiation. The effect of this treatment on the growth of certain bacteria (Bacillus subtilis) and fungi (Aspergillus niger) was studied. In general, it has been confirmed that ZnO ratio is an inhibitory factor on the growth of both microbes. As a result of treatment of cotton fabrics, as an example, the B. subtilis counts were decreased by 4 log cycles whereas the A. niger count was decreased by 2 log cycles. This finding was illustrated by observing the surface microstructure of the fabrics after they had been buried in a moist soil for two weeks. The deterioration in the weaving structure of the nontreated was so strong that it could not distinguish the strings forming the fabric. On the basis of microbial detection, it was found that the treatment with ZnO formulation causes a net reduction in the bacterial cells amounts to 78 and 62% in the case of treated cotton and cotton/polyester fabrics while the net reduction in the fungi was calculated to be 80.7 and 32%, respectively. However, it was found that the treatment with ZnO formulation caused a reduction in the thermal stability of the fabrics as indicated by thermogravimetric analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2604–2610, 2003
H2‐O influence on antigen presentation in H2‐E‐expressing mice
Authors: Alfonso Christopher , Williams G. Stuart , Karlsson Lars
Published: June 2003

MHC class II molecules sample peptides generated in the endosomal/lysosomal system for cell surface presentation to CD4+ T cells. Peptide loading requires the endosomal/lysosomal resident HLA‐DM (DM; H2‐DM, mouse), but in B cells, DM is tightly associated with HLA‐DO (DO; H2‐O, mouse). We have previously shown that H2‐O differentially modulates the processing and presentation ofdifferent antigenic epitopes on H2‐Ab molecules. Using H2‐Ead‐transgenic mice, we here show that presentation of different epitopes by H2‐Ed/b molecules is similarly influenced by H2‐O after membrane immunoglobulin‐mediated uptake of antigen. In addition, B cells from H2‐Ead‐transgenic mice (which co‐express H2‐Ab and H2‐Ed/b molecules) show an altered pattern of presentation of H2‐Ab‐restricted epitopes. In H2‐Ead‐transgenic, H2‐O‐deficient mice, further changes in the peptide repertoire were observed. Thus, H2‐Ed/b expression influences the epitopes presented by H2‐Ab, and this effect is further altered by expression of H2‐O.
Health‐seeking behaviour and rural/urban variation in Kazakhstan
Authors: Thompson Robin , Miller Nigel , Witter Sophie
Published: June 2003

This paper seeks to analyse the findings of an extensive household survey, uncovering interesting evidence of variation in health‐seeking behaviour across rural and urban areas due, it is suggested, to differences in real costs, quality of care, and perceptions of the value of health and health care. It is shown that, ceteris paribus, urban households in Kazakhstan are more likely to consult, to be admitted to hospital, to report illness, and will spend relatively more on health care.

The data suggest the need for further qualitative study into the factors underlying these patterns leading to strategies to increase the quality, acceptability and affordability of rural health services. This is important given the decline in health indicators such as life expectancy in Kazakhstan and the increased burden on households of funding health care in a time of economic insecurity and deterioration of public services. Copyright © 2002 John Wiley & Sons, Ltd.
Design and analysis of unit cost estimation studies: How many hospital diagnoses? How many countries?
Authors: Glick Henry A. , Orzol Sean M. , Tooley Joseph F. , Polsky Daniel , Mauskopf Josephine O.
Published: June 2003

We evaluated three questions that commonly arise when unit costing exercises for multinational trials are conducted: (1) In countries where investigators plan to collect hospital unit cost estimates for a selected set of diagnoses, how should one estimate unit costs for the remaining diagnoses observed in the trial for which cost data were not collected? (2) For how many hospital diagnoses should estimates be obtained? (3) For how many countries should they be obtained? We addressed these questions using unit cost data collected in four western European countries and three relative value measures from the US Medicare diagnosis‐related group (DRG) payment system.

We found that the arithmetic mean length of stay from the US DRG payment system was a good predictor of unit costs in four countries in Europe. We also found that the imputation error decreased as the number of hospital diagnoses and countries sampled increased, but that the rate of reduction in error shrank. Finally, we found that – given the existence of a reliable method for cost imputation – from a pure information standpoint, it is better to obtain estimates for fewer hospital diagnoses from more countries than the reverse. Copyright © 2002 John Wiley & Sons, Ltd.
An inquiry into the different perspectives that can be used when eliciting preferences in health
Authors: Dolan Paul , Olsen Jan Abel , Menzel Paul , Richardson Jeff
Published: June 2003

There are a number of perspectives that an individual could be asked to adopt in studies designed to elicit preferences for use in informing resource allocation decisions in health care. This paper develops a conceptual framework that clearly distinguishes between six different perspectives. It is argued that the appropriate perspective to use depends on normative considerations and the particular policy context to which it will be applied. We suggest a future research agenda that explicitly addresses these considerations and which involves direct empirical investigation into the effect of perspective on preferences. Copyright © 2002 John Wiley & Sons, Ltd.
Increasing incidence of non‐Hodgkin's lymphoma in Canada, 1970–1996: age–period–cohort analysis
Authors: Liu Shiliang , Semenciw Robert , Mao Yang
Published: June 2003

Previous studies have shown that the incidence of non‐Hodgkin's lymphoma (NHL) has increased in many parts of the world in recent decades. Using data obtained from the Canadian Cancer Registry, the present study examined time trends in NHL incidence in Canada between 1970 and 1996 and the effects of age, period of diagnosis and birth cohort on incidence patterns for each sex separately. Results showed that overall age‐adjusted incidence rates increased substantially, from 7.3 and 5.2 per 100 000 in 1970–1971 to 14.0 and 10.0 per 100 000 in 1995–1996 in males and females, respectively. Diffuse lymphoma was the major histological subtype, accounting for approximately 76% of NHL cases over the 27‐year period. The data suggest that period effects have played a major role, although birth cohort effects may also have been involved. Sex‐specific patterns of the incidence were similar over the time period of diagnosis but were distinct among recent birth cohorts. In conclusion, there is in fact a marked increase in NHL in Canada which cannot be explained in terms of improvements in diagnosis, changes in NHL classification and the increase in AIDS‐associated NHL alone. The birth cohort effect in NHL suggests that changes in risk factors may have contributed to the observed increase. Copyright © 2003 John Wiley & Sons, Ltd.
Biodistribution study of phosphonolipids: a class of non‐viral vectors efficient in mice lung‐directed gene transfer
Authors: Delépine P. , Guillaume C. , Montier T. , Clément J. C. , Yaouanc J. J. , Des Abbayes H. , Berthou F. , Le Pape A. , Férec C.
Published: June 2003

Background

A multitude of cationic lipids have been synthesized since they were first proposed for use in gene therapy. Cationic lipids are able to efficiently transfect cells both in vitro and in vivo. Whereas most research groups have focused their investigations on the toxicity of these molecules, and on the location of expression of the DNA transferred by these vectors, little has been done to determine their biodistribution and elimination pathways. Our group has developed a family of cationic lipids termed phosphonolipids. Following a large in vitro screening experiment, we have selected several molecules for in vivo testing, with some of these phosphonolipids forming lipoplexes efficient in transfecting mouse lungs. It was thus of interest to study their fate after intravenous injection.

Methods

The respective biodistributions of both the GLB43 phosphonolipid and plasmid DNA were investigated and compared with DNA expression sites. Using the optimal conditions determined for phosphonolipids, we followed the gene transfer agent and plasmid DNA distributions versus time by radiolabeling them with 14C and 32P, respectively. Otherwise, we performed imaging by radiolabeling plasmid DNA with 99mTc.

Results

The lipoplexes appear to be directly located in the lung after administration. Secondly, the plasmid is released mainly into the lungs and the phosphonolipid vector is rapidly degraded. The hydrophilic moiety of the phosphonolipid is eliminated in the urine, as is the free plasmid.

Conclusions

This study reveals that there are slight differences in the observed results depending on the technique used to label the DNA; secondly, results show that the residence time of phosphonolipids in the mouse body is related to the DNA binding time. Copyright © 2003 John Wiley & Sons, Ltd.
Variations of the climatological growing season (1951–2000) in Germany compared with other countries
Authors: Menzel Annette , Jakobi Gert , Ahas Rein , Scheifinger Helfried , Estrella Nicole
Published: June 2003

We analyse how variations in the climatological growing season, defined by single‐value thresholds of daily minimum and mean air temperature, mirror recent changes in plant phenological phases. In Germany (1951–2000, 41 climate stations), the dates of last spring frost Tmin < 0 °C (<−3 °C and <−5 °C) advance by 0.24 (0.23 and 0.32) days per year on average, and the first day when the daily mean temperature constantly exceeds 5 °C (7 °C and 10 °C) advances by 0.13 (0.21 and 0.09) days per year. The respective autumn dates are delayed up to 0.25 days per year; in total, the climatological growing season is lengthened by 0.11 to 0.49 days per year, depending on the criterion analysed. However, a certain station‐to‐station variability is displayed. Mean trends of phenological phases correspond well to those measures of the climatological growing season having similar seasonal occurrence. Thus, for example, the extension of the growing seasons of trees (up to 0.22 days per year) averages the lengthening of the period where the daily mean temperature constantly exceeds 5 °C (0.23 days per year). However, the greatest changes result for the lengthening of the frost‐free period (0.49 days per year) due to the observed stronger increase in daily minimum rather than maximum temperatures. Consequently, trees may not take advantage of the frost‐free season as before, but may profit from a reduced risk of damage by late spring frosts.

A parallel evaluation of trends in the climatological growing season in other European countries (Austria, Switzerland, Estonia) supports this finding of a stronger lengthening of the frost‐free period than that of the growing season based on daily mean air temperature. The mean lengthening of the frost‐free period of 0.50 days per year in Austria and Switzerland (1951–99, 18 stations <950 m a.s.l.) and 0.34 days per year in Estonia (1951–2000, two stations) is quite similar to that in Germany. The lengthening of the growing season (Tmean≥7 °C) in Austria and Switzerland (0.39 days per year) also approximates the respective result for Germany (0.36 days per year). However, in several cases, the trends increase with altitude (up to 500–900 m a.s.l.), but at high‐elevation climate stations (>950 m a.s.l.) weaker trends are again generally observed. Copyright © 2003 Royal Meteorological Society
Testing consumers' motivation and linguistic ability as moderators of advertising readability
Authors: Chebat Jean‐Charles , Gelinas‐Chebat Claire , Hombourger Sabrina , Woodside Arch G.
Published: June 2003

The present study focuses on testing rival hypotheses regarding the effects of advertising readability: Are the effects of readability on cognitive responses and attitudes moderated by the readers' motivation or by their linguistic ability? A two (low/high involvement) by two (strong/weak arguments) by two (low/high readability) factorial design was used to test the hypotheses. The findings support the hypothesis that readers' linguistic ability is the dominant influence factor, because low readability significantly reduces the effects of argument strength under both low and high involvement. Psycholinguistic theory provides explanation for the findings. The implications for advertising practice relate to consumers' levels of literacy. © 2003 Wiley Periodicals, Inc.
An examination of perceived behavioral control: Internal and external influences on intention
Authors: Kidwell Blair , Jewell Robert D.
Published: June 2003

We explore the dimensionality and structure of internal and external perceived behavioral control, extending research on the relationship between these control components. Two conceptual models were identified and tested in Study 1. External control was manipulated in Study 2 to further explicate hypothesized variation in perceived internal control. The results from both studies provide support for an antecedent relationship between control constructs with external control as an antecedent and internal control as the more proximate determinant of behavioral intent. Theoretical implications of findings are discussed. © 2003 Wiley Periodicals, Inc.
Impaired adrenal function after glucocorticoid therapy in children with acute lymphoblastic leukemia
Authors: Petersen Kamilla B. , Müller Jørn , Rasmussen Mette , Schmiegelow Kjeld
Published: June 2003

Background

Glucocorticoids are commonly used in the treatment of childhood acute lymphoblastic leukemia (ALL). The purpose of this study was to assess the incidence of adrenal insufficiency and the time for children with ALL to recover after treatment with the glucorticoids prednisolone or dexamethasone.

Procedure

Seventeen children, 2–15 years, with ALL were studied after receiving prednisolone (60 mg/m2/day, n = 10) for 5 weeks during remission induction therapy or dexamethasone (10 mg/m2/day, n = 7) for 3 weeks during reinduction therapy. Both drugs were tapered over 9 days. The adrenal function was assessed by an ACTH stimulation test within 2 weeks after discontinuing glucocorticoid therapy. In case of adrenal insufficiency, the ACTH test was repeated at 3–5 weeks interval, and patients were put on hydrocortisone substitution therapy.

Results

Three out of ten patients had a normal adrenal function within the first 2 weeks after prednisolone therapy. Another three patients recovered within 7 weeks, whereas the remaining four patients still showed adrenal insufficiency at the end of follow‐up after 2.5–4 months. For dexamethasone, two out of seven patients showed a normal adrenal function within the first 2 weeks. Of the remaining patients, two recovered within 7 weeks, whereas three patients still had a demonstrated adrenal insufficiency at the end of follow‐up after 4–8 months.

Conclusions

Adrenal insufficiency occurs and may persist for several months in children with ALL after treatment with high doses of prednisolone or dexamethasone. Med Pediatr Oncol 2003;41:110–114. © 2003 Wiley‐Liss, Inc.
Schur complement preconditioning for elliptic systems of partial differential equations
Authors: Loghin D. , Wathen A. J.
Published: June 2003

One successful approach in the design of solution methods for saddle‐point problems requires the efficient solution of the associated Schur complement problem. In the case of problems arising from partial differential equations the factorization of the symbol of the operator can often suggest useful approximations for this problem. In this work we examine examples of preconditioners for regular elliptic systems of partial differential equations based on the Schur complement of the symbol of the operator and highlight the possibilities and some of the difficulties one may encounter with this approach. Copyright © 2003 John Wiley & Sons, Ltd.
A latency tolerant hybrid sparse solver using incomplete Cholesky factorization
Authors: Raghavan Padma , Teranishi Keita , Ng Esmond G.
Published: June 2003

Consider the solution of large sparse symmetric positive definite linear systems using the preconditioned conjugate gradient method. On sequential architectures, incomplete Cholesky factorizations provide effective preconditioning for systems from a variety of application domains, some of which may have widely differing preconditioning requirements. However, incomplete factorization based preconditioners are not considered suitable for multiprocessors. This is primarily because the triangular solution step required to apply the preconditioner (at each iteration) does not scale well due to the large latency of inter‐processor communication. We propose a new approach to overcome this performance bottleneck by coupling incomplete factorization with a selective inversion scheme to replace triangular solutions by scalable matrix–vector multiplications. We discuss our algorithm, analyze its communication latency for model sparse linear systems, and provide empirical results on its performance and scalability. Copyright © 2003 John Wiley & Sons, Ltd.
Preparation and properties of high molecular weight polyethoxysiloxanes stable to self‐condensation by acid‐catalyzed hydrolytic polycondensation of tetraethoxysilane
Authors: Abe Yoshimoto , Shimano Ryosuke , Arimitsu Koji , Gunji Takahiro
Published: June 2003

The acid‐catalyzed controlled hydrolytic polycondensation of tetraethoxysilane (TEOS) provided polyethoxysiloxanes with weight‐average molecular weights of 2300–11,700, which depended on the reaction molar ratios of the water, catalyst, and solvent to TEOS. They were soluble in common organic solvents and stable to self‐condensation and were characterized with high silica contents of up to 67%. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2250–2255, 2003
Photocrosslinkable liquid‐crystalline block copolymers with coumarin units synthesized with atom transfer radical polymerization
Authors: Tian Yanqing , Kong Xiangxing , Nagase Yu , Iyoda Tomokazu
Published: June 2003

A new class of liquid‐crystalline (LC) homopolymers of poly{11‐[4‐(3‐ethoxycarbonyl‐coumarin‐7‐oxy)‐carbonylphenyloxy]‐undecyl methacrylate} containing a coumarin moiety as a photocrosslinkable unit with various polymerization degrees and their LC‐coil diblock and LC‐coil‐LC triblock copolymers with polystyrene as the coil segment was synthesized with the atom transfer radical polymerization method. All the homopolymers and block copolymers synthesized here exhibited narrow polydispersities, indicating well‐controlled living polymerization. Differential scanning calorimetry, polarized optical microscopy, and wide‐angle X‐ray diffraction confirmed that all the homopolymers and block copolymers exhibit a monolayer smectic A phase. Coumarin moieties in the polymers can be photodimerized under λ > 300 nm light irradiation to yield crosslinked network structures, which improve the thermal stability of a polymer nanostructure because of microphase separation. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2197–2206, 2003
Long‐range order in two‐dimensional ferromagnets: Magnetoelastic effects
Authors: Spirin Denis V.
Published: June 2003

The influence of single‐site anisotropy, dipolar interaction and magnetoelastic coupling on the stabilization of long‐range magnetic order in two‐dimensional ferromagnets is investigated. Emphasis is placed on the magnetoelastic effect. It is shown that in spite of the weakness of this interaction it makes an essential contribution to the stabilization of long‐range ferromagnetic order. Numerical calculations are performed.
Ferroelectric properties of lanthanum and titanium modified SBN ceramic system
Authors: Venet M. , Garcia D. , Eiras J. A. , M'Peko J.‐C. , Amorín H.
Published: June 2003

The dielectric properties of lanthanum (La) and titanium (Ti) modified SBN ceramics were investigated in this work. The ferroelectric to paraelectric transition temperature is found to be sensitive to the substitution degree of host ions. In particular, high values of permittivity at room temperature and a stable dielectric response in a wide range of temperature, along with low values of dielectric losses, are reported for the solid solution nominally involving the highest lattice vacancies required for electrical neutrality.
Nonlinear effects in domino dynamics of photoinduced phase transitions
Authors: Mykhaylovskyy V. V. , Ogawa T. , Sugakov V. I.
Published: June 2003

Nonlinear effects on photoinduced phase‐transition domino dynamics in one‐dimensional electron–lattice systems are studied under a condition of the two‐site photoexcitation. The system parameters, i.e. the interaction between atoms, the friction constant, and the distance between the two excited sites, for the domino process to emerge are clarified numerically. It is shown that a region of the existence of the domino dynamics increases significantly in comparison with the case of the single‐site photoexcitation.
Green function study of a mixed spin‐2 and spin‐5/2 Heisenberg ferrimagnetic system on a honeycomb lattice
Authors: Li Jun , Du An , Wei Guozhu
Published: June 2003

The magnetic properties of a mixed spin‐2 and spin‐5/2 Heisenberg ferrimagnetic system on a layered honeycomb lattice are investigated theoretically by a multisublattice Green‐function technique which takes into account the quantum nature of Heisenberg spins. We calculate the sublattice magnetization and the transition temperature of the system as functions of the interlayer coupling and the single‐ion anisotropy, and find that the compensation phenomenon exists in some parameter regime.
First principles total energy calculations of the structural and electronic properties of ScxGa1–xN
Authors: Moreno‐Armenta Maria Guadalupe , Mancera Luis , Takeuchi Noboru
Published: June 2003

In this issue's Editor's Choice [1], results of structural and electronic properties calculations of ScxGa1–xN in the full range of scandium concentrations are presented. Investigations on the relative stability of various configurations have revealed that for x < 0.65, the favoured structure is wurtzite (right figure on the cover) whereas for x > 0.65 it is the rocksalt‐like structure (left figure).

The first author, Maria Guadalupe Moreno‐Armenta, received her Ph.D. in Materials Physics from the Centro de Investigación Científica y de Educación Superior de Ensenada in 2000. She is currently assistant professor at the Centro de Ciencias de la Materia Condensada‐UNAM, México. Her research interests are in the area of solid state science, focused on first principles calculations of electronic structure from bulk semiconductors, mainly nitrides, with the main concern to propose materials for potential technological applications. She has recently started studies about the interaction mechanisms of molecules with the solid surface.
Hazardous Substance Research Centers program: An incubator for remediation research
Authors: Lasat Mitch
Published: June 2003

The Hazardous Substance Research Center (HSRC) was established by the U.S. Environmental Protection
Agency (EPA) to assist in the implementation of Superfund and to address major hazardous substance
environmental problems at a regional level. Over the past 12 years, the HSRC program has produced more than
1,200 peer‐reviewed technical articles, 27 patents and licenses, 21 new technologies for the remediation
marketplace, and provided technical assistance to more than 300 communities. Research, technology transfer, and
training are conducted by five regional multi‐university centers, which focus on different aspects of
hazardous substance management. Areas of focus include urban environments, contaminated sediments, natural
remediation and restoration technologies, abandoned mine lands, and chlorinated solvents in groundwater. This
article provides an overview of the five HSRC programs including current areas of research, field studies, and
technology transfer Internet links to access research results and remediation technology information. ©
2003 Wiley Periodicals, Inc.
Fostering collaborative inquiries by prospective and practicing elementary and middle school teachers
Authors: van Zee Emily , Lay Diantha , Roberts Deborah
Published: June 2003

The purpose of this study was to document the perspectives and experiences of participants in a complex collaboration. Prospective teachers planned and conducted science lessons and small educational research projects with mentoring from teacher researchers who are science enthusiasts. These group investigations seemed to be effective in modifying the self‐perceptions of many of the prospective teachers enrolled in a course on methods of teaching science in elementary school. According to responses on an informal evaluation at the end of the Spring 2000 group investigation, for example, most of the prospective teachers indicated that they perceived themselves to be more confident and more competent to teach science than at the beginning of the course; a few indicated they had already felt confident and competent. Common themes in the prospective teachers' responses indicated that they had learned about teaching science through inquiry, taking ownership of their own learning, researching while teaching, working in groups, and understanding themselves as learners and teachers. The teacher researchers also perceived themselves as benefiting from the collaborative process. Their responses to an e‐mail questionnaire suggested that they found working with the prospective teachers to be stimulating and cheering. They enjoyed the discussions, appreciated the help with demanding activities, grew in their own knowledge about teaching and learning, and valued the opportunities for reflection. However, organizing the group investigation was complex, due to time issues, driving distances, school schedules, unexpected teacher responsibilities, and unpredictable weather. © 2003 Wiley Periodicals, Inc. Sci Ed 87:588–612, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10070
Designed curriculum and local culture: Acknowledging the primacy of classroom culture
Authors: Squire Kurt D. , MaKinster James G. , Barnett Michael , Luehmann April Lynn , Barab Sasha L.
Published: June 2003

One of the primary challenges facing designers today is how to design curricular innovations that are appealing and useful to teachers and at the same time bring about transformative practices. While we as a learning sciences community are relatively adept at facilitating innovative case examples, we need more empirical work that examines how curricular innovations become implemented across multiple classrooms. In this paper we examine a series of four teachers implementing our technology‐rich, project‐based curriculum. We then analyze and discuss each of the four cases across two themes by (a) examining how the project‐level question was contextualized to meet local needs and (b) examining the cultural context that surrounded the implementation of the curriculum. Our interpretations suggest that contextualizing the curriculum is ultimately a local phenomenon that arises as a result of a number of factors, including students' needs, students' goals, teachers' goals, local constraints, and teacher's pedagogical values. These cases illuminate the importance of school and classroom cultures in the learning process. Ultimately, curriculum designers need to acknowledge that their designs are not self‐sufficient entities; instead, during implementation, they become assimilated as part of the cultural systems in which they are being realized. © 2003 Wiley Periodicals, Inc. Sci Ed 87:468–489, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10084
A new perspective for evaluating innovative science programs
Authors: Hickey Daniel T. , Zuiker Steven J.
Published: June 2003

This paper outlines a stridently sociocultural perspective on educational program evaluation. This perspective emerged across successive attempts to evaluate science programs in a manner consistent with sociocultural views of knowing and learning, while still yielding conventional evidence of achievement. The perspective is characterized by (1) rigorous use of multiple‐choice tests, performance assessments, and interpretive event‐based analyses, (2) a dialectical approach to reconciling conflicting conclusions from different types of individual assessments, and between individual and event‐oriented assessments, and (3) a pragmatic focus on the differences among various implementations of the innovation, with judicious, targeted use of comparison groups. Innovators facing the tension between contemporary views of knowing and learning and conventional views of accountability should find this perspective particularly useful. It is relevant for a broad range of evaluation contexts, including large‐scale externally funded innovations as well as more informal practitioner‐initiated studies, and should be useful in many content domains. © 2003 Wiley Periodicals, Inc. Sci Ed 87:539–563, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10087
What does it mean to create sustainable science curriculum innovations? A commentary
Authors: Fishman Barry J. , Krajcik Joseph
Published: June 2003

Two key issues for research on the creation of sustainable science curricula are the following: (1) How do we create curriculum innovations that will be used in classrooms after the developers or researchers depart; and (2) How do we create curriculum innovations that are scalable, such that teachers who never have direct contact with the developers may successfully enact them? We introduce the idea of usability as a guiding principle for the successful design of sustainable and scalable curricula, present a framework for examining usability in school contexts, and critique the ideas presented in this issue of Science Education using this framework. © 2003 Wiley Periodicals, Inc. Sci Ed 87:564–573, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10088