bluuebunny/crossref_metadata_2025_split huggingface dataset:
Earthquake Sensor
Authors: Yanada T. , Furukawa H. , Ichida S. , Takubo K. , Shimizu Y. , Koganemaru K. , Suzuki T. 
Published: March 2003

AbstractA new concept earthquake sensor was developed utilizing spectral intensity (SI) as a measurement value. The acceleration sensing part and signal conditioning part are all integrated in one body as a transducer. A real‐timeSIcalculation algorithm was newly developed and proved by actual simulated earthquake waveforms with a three‐axis exciter bench. A liquefaction judgment algorithm was also developed based on acceleration signals and integrated into theSIsensor. Thus, the first all‐in‐oneSIsensor with liquefaction judgment was realized. With this sensor, a new earthquake disaster prevention system for gas supply, Supreme, was developed and introduced into operation around the area of Tokyo Bay, Japan.First online publication: April 8, 2002.
Summary of ISO/TC 201 Standard XII. ISO 17973:2002—Surface chemical analysis—Medium‐resolution Auger electron spectrometers—Calibration of energy scales for elemental analysis
Authors: Seah M. P. 
Published: March 2003

AbstractThis International Standard specifies a method for calibrating the kinetic energy scale of Auger electron spectrometers with an uncertainty of 3 eV for general analytical use for identifying elements at surfaces. It is suitable for instruments used in either the direct mode or the differential mode where the resolution is equal to or less than 0.5% and the modulation amplitude for the differential mode, if used, is 2 eV peak to peak. The spectrometer shall be equipped with an inert gas ion gun or other method for sample cleaning and with an electron gun capable of operating at 4 keV or higher beam energy. This International Standard further specifies a calibration schedule. Crown Copyright © 2003. Published by John Wiley & Sons, Ltd.
Static SIMS analysis of carbonate on basic alkali‐bearing surfaces
Authors: Shaw A. D. , Cortez M. M. , Gianotto A. K. , Appelhans A. D. , Olson J. E. , Karahan C. , Avci R. , Groenewold G. S. 
Published: March 2003

AbstractCarbonate is a somewhat enigmatic anion in static secondary ion mass spectrometry (SIMS) because abundant ions containing intact CO32− are not detected when analyzing alkaline‐earth carbonate minerals common to the geochemical environment. In contrast, carbonate can be observed as an adduct ion when it is bound with alkali cations. In this study, carbonate was detected as the adduct Na2CO3·Na+ in the spectra of sodium carbonate, bicarbonate, hydroxide, oxalate, formate and nitrite and to a lesser extent nitrate. The appearance of the adduct Na2CO3·Na+ on hydroxide, oxalate, formate and nitrite surfaces was interpreted in terms of these basic surfaces fixing CO2 from the ambient atmosphere. The low abundance of Na2CO3·Na+ in the static SIMS spectrum of sodium nitrate, compared with a significantly higher abundance in salts having stronger conjugate bases, suggested that the basicity of the conjugate anions correlated with aggressive CO2 fixation; however, the appearance of Na2CO3·Na+ could not be explained simply in terms of solution basicity constants. The oxide molecular ion Na2O+ and adducts NaOH·Na+ and Na2O·Na+ also constituted part of the carbonate spectral signature, and were observed in spectra from all the salts studied. In addition to the carbonate and oxide ions, a low‐abundance oxalate ion series was observed that had the general formula Na2−xHxC2O4·Na+, where 0 < x < 2. Oxalate adsorption from the laboratory atmosphere was demonstrated but the oxalate ion series also was likely to be formed from reductive coupling occurring during the static SIMS bombardment event. The remarkable spectral similarity observed when comparing the sodium salts indicated that their surfaces shared common chemical speciation and that the chemistry of the surfaces was very different from the bulk of the particle. Copyright © 2003 John Wiley & Sons, Ltd.
The use of regression models for medians when observed outcomes may be modified by interventions
Authors: White Ian R. , Koupilova Ilona , Carpenter James 
Published: March 2003

AbstractSome outcomes used in epidemiological studies and clinical trials are prone to modification by interventions, for example, individuals with high blood pressure are likely to receive antihypertensive medication. Often the scientific interest is in the relationship of covariates (exposures or randomized treatment) to the outcomes that would have been observed in the absence of intervention. We compare three approaches to the analysis of such data: ignoring the intervention; excluding individuals who receive the intervention, and assuming that individuals who receive the intervention have underlying outcomes above the median. The latter approach requires comparison of median outcomes between groups. In many situations it is plausible that neither the probability of intervention nor the effect of intervention depend on the covariates. In this case we show that analysis of medians is unbiased in general, that the other approaches are biased towards the null but that ignoring the intervention typically has the greatest power for detecting an effect. In other situations, ignoring the intervention and excluding individuals who receive the intervention may be biased towards or away from the null, and we recommend analysis of medians. We illustrate practical analysis of medians in a study of the association between adult blood pressure and birth weight. Adjustment for confounders is performed by median regression. We show that the significance levels are comparable to those derived from logistic regression. We also discuss the effect of grouping of blood pressure and the need for bootstrap standard errors. Copyright © 2003 John Wiley & Sons, Ltd.
Identifying effective and/or safe doses by stepwise confidence intervals for ratios
Authors: Bretz Frank , Hothorn Ludwig A. , Hsu Jason C. 
Published: March 2003

AbstractTypical randomized clinical dose‐finding studies consist of the comparison of several doses of a drug versus a placebo. Interest lies in estimating relevant doses among those under investigation for efficacy and safety variables, such as the minimum effective dose or the maximum safe dose (or estimating both doses simultaneously). Step‐down procedures have been proposed for comparing the standardized differences of the dose groups against placebo. In this paper we consider the ratio of population means and propose stepwise confidence intervals for these ratios. These confidence intervals do not require multiplicity adjustments and yield the same decisions as the associated test procedures. In addition, several power concepts are investigated within the present framework. The results allow sample size determination in the design phase of a study for the probability of estimating correctly the dose of interest. Auxiliary results of a numerical study show the range of application of these methods. Copyright © 2003 John Wiley & Sons, Ltd.
A score test for establishing non‐inferiority with respect to short‐term survival in two‐sample comparisons with identical proportions of long‐term survivors
Authors: Broët P. , Tubert‐Bitter P. , De Rycke Y. , Moreau T. 
Published: March 2003

AbstractIn recent years randomized trials designed to establish non‐inferiority of a new treatment as compared to a standard one have been more widely used. Two‐sample statistics have been proposed for this equivalence testing problem. However, they are not suited to situations where a long‐term survivor fraction is expected. In this paper we propose a score test designed for establishing non‐inferiority for the new treatment as compared to the standard one while assuming identical long‐term survivor rates. Simulations results show that the proposed statistic has satisfactory size and power as long as certain restricting conditions are verified. A breast cancer trial is analysed as an example. Copyright © 2003 John Wiley & Sons, Ltd.
Issues in designing flexible trials
Authors: Posch Martin , Bauer Peter , Brannath Werner 
Published: March 2003

AbstractWe outline the general framework of adaptive combination tests and discuss their relationship to flexible group sequential designs. An important field of applications is sample size reassessment. We discuss reassessment rules based on conditional power arguments using either the observed or the prefixed effect size. These rules tend to lead to large expected sample sizes for small actual effects. However, the application of a maximal bound for the second stage sample size leads to more favourable properties. Additionally, we consider an optimized reassessment rule in terms of expected sample sizes. Since the adaptive design does not use the classical test statistics for some types of sample size reassessments, the adaptive test may reject the null hypothesis while the classical one‐sample test does not. We characterize sample size reassessment rules, where such inconsistencies are avoided. Finally, the extension of flexibility to the number of stages is explored. In the first interim analysis a second interim analysis is only planned if the chance to achieve a decision there is high. This leads to savings in the average number of interim analysis performed, without paying a noticeable price in terms of expected sample size. Copyright © 2003 John Wiley & Sons, Ltd.
Blinded sample size reassessment in non‐inferiority and equivalence trials
Authors: Friede Tim , Kieser Meinhard 
Published: March 2003

AbstractEven in situations where the design and conduct of clinical trials is highly standardized, there may be a considerable between‐study variation in the observed variability of the primary outcome variable. As a consequence, performing a study in a fixed sample size design implies a considerable risk of resulting in a too high or too low sample size. This difficulty can be alleviated by applying a design with internal pilot study. After a provisional sample size calculation in the planning stage, a portion of the planned sample is recruited and the sample size is recalculated on the basis of the observed variability. To comply with the requirement of some regulatory guidelines only blinded data should be used for the reassessment procedure. Furthermore, the effect on the type I error rate should be quantified. The current literature presents analytical results on the actual level in the t‐test situation only for superiority trials. In these situations, blinded sample size recalculation does not lead to an inflation of the type I error rate. We extended the methodology to non‐inferiority and equivalence trials with normally distributed outcome variable and hypotheses formulated in terms of the ratio and difference of means. Surprisingly, in contrast to the case of testing superiority, we observed actual type I error rates above the nominal level. The extent of inflation depends on the required sample size, the sample size of the internal pilot study, and the standardized equivalence or non‐inferiority margin. It turned out that the elevation of the significance level is negligible for most practical situations. Nevertheless, the consequences of sample size reassessment have to be discussed case by case and regulatory concerns with respect to the actual size of the procedure cannot generally be refuted by referring to the fact that only blinded data were used. Copyright © 2003 John Wiley & Sons, Ltd.
A critical systems intervention to improve the implementation of a district health system in KwaZulu–Natal
Authors: Luckett Sidney , Grossenbacher Kaspar 
Published: March 2003

AbstractThis paper reports on a critical systems inquiry into the complexities of the implementation of a District Health System in the KwaZulu–Natal province of post‐Apartheid South Africa. The inquiry process, which was ‘governed’ by Checkland's Soft Systems Methodology (SSM) and followed the four‐phase learning cycle developed by Kolb, produced ‘conceptual models’ which enabled participant stakeholders to gain fresh perspectives on the context and, in so doing, to get the implementation process ‘unstuck’. At the theoretical/methodological level the paper contributes to the growing literature on the combination of systems methods by illustrating how conceptual models of purposeful human activity, a method intrinsic to SSM, were constructed from the participatory use of Concept Maps and Sign‐graph Diagrams. We also reflect on the interrelationship between methodology/method combination and two other aspects of the intervention that we considered to be important for maintaining the ‘systemicity’ of the intervention, viz., the inquiry context and boundary critique. Copyright © 2003 John Wiley & Sons, Ltd.
Attitude stabilization of a rotating spacecraft with flexible elements and a magnetohydrodynamic control system
Authors: Rabinovich Boris , Grishin Alexey 
Published: March 2003

AbstractRotating spacecraft with flexible spike antennas located along their rotation axis can be seriously affected by instability problems. The Auroral Probe of the INTERBALL Project is a typical example of such an object. It is shown that magnetohydrodynamic (MHD) elements may be effectively applied for control of the spacecraft. In particular, by using MHD elements it is possible to stabilize the rotation of a spacecraft without reducing its angular velocity. It is important that the MHD control system does not have hinges and does not need any special fuel storage. Copyright © 2003 John Wiley & Sons, Ltd.
Robust active control for uncertain structural systems with acceleration sensors
Authors: Wang Sheng‐Guo 
Published: March 2003

AbstractNatural hazards such as earthquakes and strong wind events place large forces on tall, slender structures and on long‐span bridges that inherit numerous uncertainties due to model errors, stress calculations, material properties, and load environments. Thus, a robust feedback control for structural systems is needed. This paper develops a robust active control approach for uncertain structural systems with acceleration sensors and white noise. The approach is based on a robust state feedback control, with the robust α‐degree relative stability, robust H∞ δ‐degree disturbance rejection and robust H2 optimality, and a modified Kalman filter, with α0‐degree relative' stability. The uncertainties considered include structural ones in the system and control input matrices and multiplicative nonstructural ones in the disturbance input matrices. Special singular value decomposition (SVD) is applied to structured uncertain structures. Numerical simulations excited by the 1940 El Centro, California, earthquake data have been carried out for the proposed different robust controllers and LQG for comparison. The resulting approach to robust control may be applied to analysis and design of practical structural systems. Copyright © 2003 John Wiley & Sons, Ltd.
Rundown of a transient potassium current is attributable to changes in channel voltage dependence
Authors: Hattori Satoko , Murakami Fujio , Song Wen‐Jie 
Published: March 2003

AbstractMany ionic currents undergo significant rundown during whole‐cell recording. Although rundown is an artifact associated with the recording method, studying the mechanism of rundown may lead to understanding mechanisms regulating channel functions in physiological conditions. The mechanisms for rundown, however, remain obscure for many channels. Here we have studied the mechanism for rundown of an A‐type K+ current in mouse striatal cholinergic interneurons. The interneuron expressed a prominent component of A‐type current which exhibited significant rundown during whole‐cell recording. When the current was assessed with a highly hyperpolarized prepotential (–140 mV), however, the rundown was virtually fully suppressed, suggesting its being dependent on voltage. Estimation of channel voltage dependence revealed that both activation and inactivation curves shifted towards hyperpolarized potentials during rundown. The shift was suppressed by intracellular ATP, but was affected neither by phosphatase inhibitors nor by antioxidative reagents. The gradual shift of inactivation curve towards negative potentials would make the holding potential progressively inactivate the channel, resulting in apparent loss of activity of the channels. Our results thus provide a biophysical explanation for rundown of A‐type current. Synapse 48:57–65, 2003. © 2003 Wiley‐Liss, Inc.
Strategic elements of Eastman Kodak's successful market entry in Russia
Authors: Anders Gary C. , Usachev Danila A. 
Published: March 2003

AbstractEastman Kodak is a global imaging company with extensive reach and capabilities. This article examines
Kodak's entry strategy in Russia. It explains that Kodak was able to succeed through strong personal
relations with stakeholders and decisions to invest in local production. Kodak established consumer acceptance
through open and frequent communications with their customers. This, combined with a multifaceted marketing
strategy, helped them survive the Russian financial crisis. We argue that Kodak's success has been greatly
facilitated by a set of policies that include appropriate adaptations of Western marketing and human resources
practices. © 2003 Wiley Periodicals, Inc.
The Palm Island mystery disease 20 years on: A review of research on the cyanotoxin cylindrospermopsin
Authors: Griffiths Dilwyn J. , Saker Martin L. 
Published: March 2003

AbstractPoisoning of humans resulting from consumption of water affected by the toxic cyanobacterium Cylindrospermopsis raciborskii was first reported almost 20 years ago from Palm Island, northern Queensland, Australia. Since that time a great deal has been learned about this organism and cylindrospermopsin (CYN), the toxin it produces. This article reviews the information now available to us. It summarizes aspects of the chemistry of the toxin—now known to be produced by some cyanobacterial species other than C. raciborskii—and its biosynthesis and chemical synthesis in vitro, as well as its detection and measurement by chemical and biological assay. Some of the factors affecting toxin production by cultured isolates of C. raciborskii are reviewed and the conditions that cause its release from the cells described. The occurrence of CYN in water bodies and the management strategies used to minimize the harmful effects of the toxin are outlined. These include a range of water‐treatment practices now in place to remove CYN‐producing organisms and/or to neutralize the toxin together with some management procedures that have been tried, with varying degrees of success, to prevent buildup of blooms of the offending organisms. Some of the public‐health considerations arising from exposure to water supplies affected by CYN are summarized along with the risk factors and guidance values as they are currently applied. Among the more recent developments described are those that come from the application of molecular techniques for characterizing toxic and nontoxic strains and for exploring the genetic aspects of CYN production. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 78–93, 2003
Multiplex PCR assay for Cylindrospermopsis raciborskii and cylindrospermopsin‐producing cyanobacteria
Authors: Fergusson Kim M. , Saint Christopher P. 
Published: March 2003

AbstractWater bodies are routinely monitored for the presence of potentially toxic cyanobacteria; however, the methodology for confirming toxicity is currently complex and expensive. Here we describe the application of gene‐based technology to rapidly identify cylindrospermopsin‐producing cyanobacteria, specifically, Cylindrospermopsis raciborskii. A multiplex polymerase chain reaction (PCR) test was developed that simultaneously identified polyketide synthase (pks) and peptide synthetase (ps) determinants associated with cylindrospermopsin production and distinguished C. raciborskii from other cylindrospermopsin‐producing cyanobacteria of the species Anabaena bergii and Aphanizomenon ovalisporum, by targeting the rpoC1 gene. Twenty‐one C. raciborskii, 5 A. bergii, 10 Aph. ovalisporum isolates and 3 environmental samples all yielded PCR results consistent with their toxicological status, as assessed by high‐performance liquid chromatography coupled to mass spectrometry or matrix‐assisted laser desorption ionization–time‐of‐flight mass spectrometry, and C. raciborskii was always correctly identified. The PCR test is a rapid, reliable, and economical way of assessing the toxic potential of cyanobacterial blooms formed by these organisms. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 120–125, 2003.
Successful outcome of advanced abdominal pregnancy with exclusive omental insertion
Authors: Varma R. , Mascarenhas L. , James D. 
Published: March 2003

AbstractWe report the case of an advanced abdominal pregnancy with exclusive omental insertion whose extrauterine location was not established until delivery by Cesarean section at 35 weeks' gestation. It is hard to believe that omental placentation alone would be sufficient to sustain a pregnancy beyond a gestation where the fetus is viable. However, this report challenges such myths and opens the debate as to what represents the minimal placental maternal viscus contact necessary to achieve fetal viability. The case also demonstrates the continuing difficulty in diagnosing this rare but serious condition despite advances in obstetric imaging, and advocates methods to avoid missing the diagnosis, which could be easily incorporated at booking and mid‐trimester scans. Apart from this case, few reports describe normal umbilical artery Doppler velocimetry in advanced abdominal pregnancy. There is a paucity of research on suitable clinical investigations prognostic for abdominal pregnancy, although this case provides further evidence for the use of Doppler as a useful surveillance tool in such cases. Finally, this case propagates the ethical and clinical controversy that exists in managing abdominal pregnancy, particularly when diagnosed late after attaining fetal viability. Expectant management may represent a feasible alternative to surgical termination provided the woman is fully informed of the attendant risks and close surveillance of the pregnancy is undertaken. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.
In‐utero development of the fetal colon and rectum: sonographic evaluation
Authors: Zalel Y. , Perlitz Y. , Gamzu R. , Peleg D. , Ben‐Ami M. 
Published: March 2003

AbstractObjectiveTo construct a normal range for the internal diameter of the fetal descending colon and rectum during gestation.Subjects and MethodsThis was a prospective, cross‐sectional study including 379 healthy pregnant women with normal singleton pregnancies at 19–40 weeks of gestation. Measurements of the fetal descending colon (maximum internal diameter) and the fetal rectum (at the level of the bladder, measuring the anteroposterior diameter), were performed by high‐resolution transabdominal sonography.ResultsAdequate bowel measurements were obtained in all 379 fetuses. The diameter of the descending colon and rectum plotted as a function of gestational age had a sigmoid curve; the curve estimation was expressed by a cubic regression equation with R2 of 0.848 and 0.831, respectively (P < 0.0001). The normal mean and the 95% prediction limits were defined.ConclusionThe present data provide a normal range of fetal bowel (descending colon and rectum) diameters from the early second trimester of pregnancy onwards. They may allow intrauterine assessment of the development of the fetal colon and may serve as reference values in the detection of anomalies of the fetal bowel. Copyright © 2003 ISUOG. Published by John Wiley & Sons, Ltd.