bluuebunny/crossref_metadata_2025_split huggingface dataset:
A transformer resonant phase‐shifted PWM DC–DC converter for X‐ray power generator and its fuzzy logic‐based learning control scheme
Authors: Sun Junming , Takano Hiroshi , Nakaoka Mutsuo 
Published: August 2002

AbstractIn general, medical‐use high‐voltage X‐ray power generators are operated at a variety of required output DC voltages and output current settings for the X‐ray tube. A phase‐shifted PWM inverter‐fed DC–DC power converter with a high‐voltage transformer parasitic resonant link which is used for an X‐ray power generator inherently has stiff nonlinear characteristics due to phase‐shifted voltage regulation and diode cutoff operation in a high‐voltage rectifier because of the wide load setting ranges in practical applications. However, the superior output voltage response required for a medical‐use X‐ray power generator could not be sufficiently implemented by various modern linear control approaches because a precise mathematical description with dynamic modeling could not be formulated for wide load variations. For controlling such a nonlinear DC–DC power conversion system, a fuzzy reasoning‐based learning control technique that duplicates human capabilities and much experience in understanding the dynamic and static behavior of the system are more suitable and effective. This paper presents a phase‐shifted PWM full bridge inverter‐type high‐voltage DC–DC power converter with a high‐voltage transformer parasitic link and its fuzzy‐based learning controller, which has excellent dynamic and static behavior, for use in a medical X‐ray power generator operating at a wide variety of load settings. The effectiveness of the feasible fuzzy learning technique used for control of the DC–DC power converter is discussed and evaluated based on computer simulations and experimental results in a laboratory setup. It is demonstrated that the feasible fuzzy learning control scheme suitable for this converter is more effective and practical in improving the system output voltage response performance in both transient and steady states for medical‐use X‐ray power generators. The results of simulations and experiments for this converter are presented in order to illustrate the operating performance of the proposed X‐ray power generator operated by the feasible fuzzy‐based learning control implementation. © 2001 Scripta Technica, Electr Eng Jpn, 136(2): 58–71, 2001
Chemoprevention of heterocyclic amine‐induced mammary carcinogenesis in rats
Authors: Hirose Masao , Nishikawa Akiyoshi , Shibutani Makoto , Imai Toshio , Shirai Tomoyuki 
Published: August 2002

Abstract2‐Amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP) is one of the most prevalent carcinogenic heterocyclic amines in the environment, targeting the colon, prostate, pancreas, and mammary gland in rodents. Chemopreventive effects of synthetic and naturally occurring compounds on PhIP‐induced rat mammary carcinogenesis were investigated in a series of experiments. In a PhIP feeding model, groups of 20–21 female F344 rats each, were treated with 0.02% PhIP alone or PhIP plus 0.5% 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone (HTHQ), 1% green tea catechins, 1% α‐tocopherol, 0.1% ellagic acid, or 1% chlorophyllin, each in the diet, or 0.1% caffeine in drinking water for 52 weeks. To assess the mechanism of HTHQ and caffeine inhibition of PhIP‐induced carcinogenesis, effects of these compound on the in vitro metabolic activation of PhIP were examined in the presence of S9 mix. In the next series of experiments, the PhIP intragastric dose model was applied to allow separate investigation of the effects of chemicals during the initiation and postinitiation periods. In these experiments, female Sprague–Dawley rats were given eight intragastric doses of 100 mg/kg body weight during the first 4–8 weeks for initiation. Either during initiation or after initiation, or only after initiation, animals were treated with either corn or perilla oil at doses of 5 and 20%, conjugated fatty acid derived from safflower oil (CFA‐S) or perilla oil (CFA‐P) at a dose of 1%, arctiin at doses of 0.02 and 0.2% in the diet, or sodium nitrite (NaNO2) at a dose of 0.2% in drinking water. In the PhIP feeding model, administration of PhIP alone for 52 weeks induced adenocarcinomas in 40% of rats, but the incidence was remarkably reduced to 5% by the simultaneous treatment with 0.5% HTHQ, a strong lipophilic phenolic antioxidant, or to 10% by 0.1% caffeine. Administration of 1% chlorophyllin exerted similar, albeit weaker, effects. α‐Tocopherol at a dose of 0.5% only reduced the multiplicity of carcinomas, and 1% green tea catechins only the mean size of mammary tumors. In a metabolic activation study of PhIP, HTHQ and caffeine clearly inhibited the formation of metabolites. In the PhIP gastric dose model, among the naturally occurring compounds examined, a plant lignan arctiin, perilla oil, which contains a large amount of n‐6 α‐linolenic acid, and CFA‐S or CFA‐P inhibited mammary tumor development, particularly in the postinitiation period, although a clear dose response was not observed. Treatment with 0.2% NaNO2 in the initiation period was found to lower the volume of mammary tumors. The present results indicate that a number of compounds may be candidate chemopreventive agents against PhIP‐induced mammary carcinogenesis, acting through different mechanisms and depending on the stage of carcinogenesis. Environ. Mol. Mutagen. 39:271–278, 2002. © 2002 Wiley‐Liss, Inc.
Predictive distributions in risk analysis and estimation for the triangular distribution
Authors: Joo Yongsung , Casella George 
Published: August 2002

AbstractMany Monte Carlo simulation studies have been done in the field of risk analysis. This article demonstrates the importance of using predictive distributions (the estimated distributions of the explanatory variable accounting for uncertainty in point estimation of parameters) in the simulations. We explore different types of predictive distributions for the normal distribution, the lognormal distribution and the triangular distribution. The triangular distribution poses particular problems, and we found that estimation using quantile least squares was preferable to maximum likelihood. Copyright © 2001 John Wiley & Sons, Ltd.
Confidence intervals for the calibration estimator with environmental applications
Authors: Müller I. , El‐Shaarawi A. H. 
Published: August 2002

AbstractThe article investigates different estimation techniques in the simple linear controlled calibration model and provides different types of confidence limits for the calibration estimator. In particular, M‐estimation and bootstrapping techniques are implemented to obtain estimates of regression parameters during the training stage. Moreover, bootstrap is used to construct several types of confidence intervals that are compared to the classical approach based on the assumption of normality. For some of these intervals, the second order asymptotic properties can be established by means of Edgeworth expansions. Two data sets—one on space debris and the other on bacteriological counts in water samples—are used to illustrate the method's environmental applications. Copyright © 2002 John Wiley & Sons, Ltd.
Active interaction control of civil structures. Part 1: SDOF systems
Authors: Zhang Yunfeng , Iwan W. D. 
Published: August 2002

AbstractThis paper presents a family of semi‐active control algorithms termed as active interaction control (AIC) used for seismic response control of civil structures. AIC control algorithms include active interface damping (AID), optimal connection strategy (OCS) and tuned interaction damping (TID). A typical SDOF AIC system consists of a primary structure, an auxiliary structure and an interaction element. The auxiliary structure typically has stiffness comparable to that of the primary structure while its natural frequency is much higher than that of the primary structure. Interactions between the primary and the auxiliary structures are defined by specific AIC control logic such that vibrational energy is extracted from the primary structure into the auxiliary structure during a locking phase and dissipated in the auxiliary structure in the subsequent unlocking phase. The stability of AIC control algorithms is shown using the Lyapunov direct method. The efficacy of AIC control algorithms is demonstrated by the results of numerical simulations of SDOF systems subjected to seismic ground motions. Practical issues such as sampling period and time delay are also investigated in this study. Copyright © 2001 John Wiley & Sons, Ltd.
Performance evaluation of new steel frame buildings for seismic loads
Authors: Lee Kihak , Foutch Douglas A. 
Published: August 2002

AbstractThe damage observed after the Northridge Earthquake exposed a weakness of design and construction procedures and led to the development of performance‐based guidelines for design of new steel frame structures. As part of Phase 2 of the FEMA/SAC project, this study focused on performance prediction of new steel special moment resisting frame buildings assumed to be built after the Northridge earthquake. A total of 26 post‐Northridge buildings that represent typical steel SMRF buildings based on the new seismic code (1997 NEHRP) and pre‐qualified post‐Northridge connections were designed. Then, the analytical building models considering the effects of ductile connections, panel zone deformation and interior gravity frames were developed and subjected to sets of 20 SAC ground motions representing the 2/50 and 50/50 hazard levels. A new procedure that allows the design professional to determine the confidence level for achieving a given performance objective is presented. Using the drift demand and capacities, confidence levels that post‐Northridge buildings will satisfy the collapse prevention and immediate occupancy performance level are calculated. All of the post‐Northridge buildings exhibit a high confidence of performing well in future earthquakes. Copyright © 2001 John Wiley & Sons, Ltd.
Essential oil composition of Zanthoxylum alatum seeds from northern India
Authors: Jain Neetu , Srivastava S. K. , Aggarwal K. K. , Ramesh S. , Kumar Sushil 
Published: August 2002

AbstractThe seeds of Zanthoxylum alatum Roxb., on hydrodistillation, gave 1.5% of oil (v/w). GC and GC–MS analysis of the oil resulted in the identification of 56 constituents, representing 99.5% of the oil. Linalool (71%), limonene (8.2%), β‐phellandrene (5.7%) and (Z)‐methylcinnamate (4.9%) were the major components. It is suggested that the seeds of Z. alatum can be used as a commercial source for the isolation of linalool. Copyright © 2001 John Wiley & Sons, Ltd.
Comparison of volatile compounds released during the consumption of Cheddar cheese with compounds extracted by vacuum distillation using gas chromatography–olfactometry
Authors: O'Riordan P. J. , Delahunty C. M. 
Published: August 2002

AbstractBuccal headspace analysis is an in vivo extraction technique capable of extracting volatile compounds released during consumption in concentration ratios that stimulate the olfactory receptors. Vacuum distillation is designed to measure the total volatile profile of a food and as a result pays little attention to conditions in the mouth that determine volatile release and aroma stimulation. Volatile extracts of mature Cheddar cheese were obtained using buccal headspace analysis and vacuum distillation. Cheddar cheese volatile extracts were compared using gas chromatography–olfactometry and gas chromatography–mass spectrometry. Estimation of odour intensity was carried out using a time–intensity gas chromatography–olfactometry technique similar to OSME. Odour‐active volatile compounds identified in Cheddar cheese buccal headspace analysis extracts included dimethyl sulphide, 2,3‐butanedione, 3‐methylbutanal, toluene, ethyl butyrate, hexanal, 2‐heptanone, heptanal, α‐pinene, methional, ethyl hexanoate and dimethyl trisulphide. All of these volatile compounds have previously been associated with the volatile profile of Cheddar cheese. Vacuum distillation obtained a near‐complete volatile extract of Cheddar cheese, which was distinguished from buccal headspace analysis extracts by the presence of low vapour pressure odour‐active volatile compounds. Significant differences (p < 0.05) between extractions were determined for the quantities of ethyl butyrate, 2‐heptanone and ethyl hexanoate, the odours of which were also identified in both extractions. Buccal headspace analysis and vacuum distillate principal aromagrams of mature Cheddar cheese were obtained using non‐centred principal components analysis. Qualitative odour differences were observed between both extractions, in particular for odour intensity measurements of one odour, ‘raw mushroom’. Tentative relationships between gas chromatography–olfactometry odour intensity measurements and corresponding gas chromatography–mass spectrometry quantitative measurements were established. Copyright © 2001 John Wiley & Sons, Ltd.
A σ‐coordinate three‐dimensional numerical model for surface wave propagation
Authors: Lin Pengzhi , Li C. W. 
Published: August 2002

AbstractA three‐dimensional numerical model based on the full Navier–Stokes equations (NSE) inσ‐coordinate is developed in this study. Theσ‐coordinate transformation is first introduced to map the irregular physical domain with the wavy free surface and uneven bottom to the regular computational domain with the shape of a rectangular prism. Using the chain rule of partial differentiation, a new set of governing equations is derived in theσ‐coordinate from the original NSE defined in the Cartesian coordinate. The operator splitting method (Li and Yu,Int. J. Num. Meth. Fluids1996;23: 485–501), which splits the solution procedure into the advection, diffusion, and propagation steps, is used to solve the modified NSE. The model is first tested for mass and energy conservation as well as mesh convergence by using an example of water sloshing in a confined tank. Excellent agreements between numerical results and analytical solutions are obtained. The model is then used to simulate two‐ and three‐dimensional solitary waves propagating in constant depth. Very good agreements between numerical results and analytical solutions are obtained for both free surface displacements and velocities. Finally, a more realistic case of periodic wave train passing through a submerged breakwater is simulated. Comparisons between numerical results and experimental data are promising. The model is proven to be an accurate tool for consequent studies of wave‐structure interaction. Copyright © 2002 John Wiley & Sons, Ltd.
Consistent chromosome 10 rearrangements in four newly established human hepatocellular carcinoma cell lines
Authors: Pang Elizabeth , Wong Nathalie , Lai Paul B.‐S. , To Ka‐Fai , Lau Wan‐Yee , Johnson Philip J. 
Published: August 2002

AbstractCancer cell lines represent an invaluable resource for isolation of novel genes relevant to tumor pathogenesis and as in vitro models. In this study, we report on the successful establishment of four cell lines from hepatocellular carcinoma tissue. These cell lines, designated HKCI‐1, HKCI‐2, HKCI‐3, and HKCI‐4, have been growing continuously for more than 24 months and have been passaged more than 50 times. A comprehensive cytogenetic characterization on the primary tumors and the derived cell lines was achieved by the combined approach of spectral karyotyping and comparative genomic hybridization. Chromosomal imbalances from the primary tumors were also maintained in the cell lines and included gains of 1q, 6p, 7, 10p, 17q, and 20 and loss of 4q. Recurring translocations included t(X;11), t(1;10), t(4;16), i(5)(p10), t(7;21), t(8;17), t(9;22), i(10)(p10), t(14;20), t(16;22), and t(17;19). It was noteworthy that consistent chromosome 10 aberrations, in particular t(1;10)(q10;p10), were detected in all four cell lines. Furthermore, microsatellite analysis on primary tumor and derived cell lines indicated a common deleted region of 10q23‐q26. The functional importance of chromosome 10 aberrations in relation to the pathogenesis of HCC is unknown; however, the high frequency with which such aberrations were maintained in the cell lines suggests proliferative advantages of 10q loss or 10p gain in the multistep development of hepatic neoplasia. © 2002 Wiley‐Liss, Inc.
Darwin would be proud: Bioturbation, dynamic denudation, and the power of theory in science
Authors: Johnson D. L. 
Published: August 2002

AbstractCharles Darwin's worm book influenced many early researchers who, following his lead, demonstrated how soil biota mechanically generate new strata and soil horizons, as well as blur or destroy them. Such early observations on biomechanical processes failed to find visibility in our models of landscape evolution for several reasons, chief of which are (1) except for ichnology, an Earth sciences tradition of adopting frameworks where biomechanical processes are absent and (2) a lapse of over 100 years after Darwin before a genetic language backed by supporting theory appeared that could showcase the importance of such processes. Examples of influential Earth science frameworks in which biomechanical processes are absent are the V.V. Dokuchaev–USDA–H. Jenny soil formational (five factors) paradigm, W.M. Davis' geographical cycle, the W. Penck–L.C. King–R.V. Ruhe backwasting‐pedimentation concept, the stratigraphic Law of Superposition, and other traditional approaches to archaeology, geomorphology, and pedology. Examples of recent genetic language that serve to ameliorate the problem are soil thickness concepts, biomantle, bioturbation, faunalturbation, floralturbation, and pedoturbation. Examples of recent supporting theory that incorporate biomechanical processes are soil evolution, biomantle evolution, dynamic pedogenesis, and the dynamic denudation framework advocated here. Dynamic denudation is a unified synthesis that elevates bioturbation to parity levels with other major archaeogenic, geomorphogenic, and pedogenic processes. The general framework and its principal elements are summarized and simulated by diagrams and augmented by photographs taken in disparate parts of the world. The model has useful explanatory and predictive value in archaeology, geomorphology, pedology, and other surficial process research. © 2002 John Wiley & Sons, Inc.
The cerebellar deficient folia (cdf) gene acts intrinsically in Purkinje cell migrations
Authors: Park Chankyu , Finger Jacqueline H. , Cooper Jonathan A. , Ackerman Susan L. 
Published: August 2002

AbstractSummary: Cerebellar deficient folia (cdf) is a recently identified mouse mutation causing ataxia and cerebellar abnormalities including lobulation defects and abnormal placement of a specific subset of Purkinje cells. To understand the etiology of the cerebellar defects in cdf mutant mice, we examined postnatal development of the cdf/cdf cerebellum. Our results demonstrate that Purkinje cell ectopia and foliation defects are apparent at birth, suggesting the cdf mutation disrupts the positioning of many, but not all, Purkinje cells during development. In addition to cerebellar abnormalities, we observed lamination defects in the hippocampus of cdf mutant mice, although neocortical defects were not seen. Furthermore, ectopic Purkinje cells in cdf/cdf mice express an increased level of Dab1 protein, as previously observed in mice with mutations in genes in the reelin signaling pathway. Lastly, analysis of cdf ↔ROSA26 chimeric mice demonstrated that the cdf mutation is intrinsic to Purkinje cells. We suggest that the cdf gene product is required in a subset of Purkinje cells, possibly to respond to Reelin signals. genesis 32:32–41, 2002. © 2002 Wiley‐Liss, Inc.
Quaking is essential for blood vessel development
Authors: Noveroske Janice K. , Lai Lihua , Gaussin Vinciane , Northrop Jennifer L. , Nakamura Hisashi , Hirschi Karen K. , Justice Monica J. 
Published: August 2002

AbstractFor nearly 40 years functional studies of the mouse quaking gene (qkI) have focused on its role in the postnatal central nervous system during myelination. However, the homozygous lethality of a number of ENU‐induced alleles reveals that quaking has a critical role in embryonic development prior to the start of myelination. In this article, we show that quaking has a previously unsuspected and essential role in blood vessel development. Interestingly, we found that quaking, a nonsecreted protein, is expressed in the yolk sac endoderm, adjacent to the mesodermal site of developing blood islands, where the differentiation of blood and endothelial cells first occurs. Antibodies against PE‐CAM‐1, TIE‐2 and SM‐α‐actin reveal that embryos homozygous for the qkk2 allele have defective yolk sac vascular remodeling and abnormal vessels in the embryo proper at midgestation, coinciding with the timing of embryonic death. However, these mutants exhibit normal expression of Nkx2.5 and α‐sarcomeric actin, indicating that cardiac muscle differentiation was normal. Further, they had normal embryonic heart rates in culture, suggesting that cardiac function was not compromised at this stage of embryonic development. Together, these results suggest that quaking plays an essential role in vascular development and that the blood vessel defects are the cause of embryonic death. genesis 32:218–230, 2002. © 2002 Wiley‐Liss, Inc.
Middle/Late Cambrian intracontinental rifting in the central West Sudetes, NE Bohemian Massif (Czech Republic): geochemistry and petrogenesis of the bimodal metavolcanic rocks
Authors: Dostal Jaroslav , Patočka František , Pin Christian 
Published: August 2002

AbstractThe Early Palaeozoic East Krkonoše Complex (EKC) situated in the central West Sudetes, NE Bohemian Massif, is a volcano‐sedimentary suite containing abundant mafic and felsic volcanics metamorphosed to greenschist facies.The trace element distribution patterns and Nd isotope signatures (ENd500 = + 3.1 to + 6.6) of the metabasites (metabasalts) indicate that they may be related to a rising mantle diapir associated with intracontinental rifting. At the early stage, limited melting of an upwelling asthenosphere produced alkali basalts and enriched tholeiites which compositionally resemble oceanic island basalts. A later stage of rifting with larger degrees of melting at shallower depths generated tholeiitic basalts with E‐MORB to N‐MORB characteristics.The values of (87Sr/86Sr)i = 0.706 and ENd500 = − 5 ±1 of the porphyroids (metarhyolites) as well as the lack of rocks with intermediate compositions suggest that the felsic rocks were formed by a partial melting event of continental crust triggered by mantle melts.The geochemistry of the EKC bimodal metavolcanics and their association with abundant terrigenous metasediments suggest that the felsic–mafic volcanic suite was generated during intracontinental rifting. This process, widespread in Western and Central Europe during the Early Palaeozoic, is evidence of large‐scale fragmentation of the northern margin of the Gondwana supercontinent. Copyright © 2001 John Wiley & Sons, Ltd.