bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrostatic fluid pressure enhances matrix synthesis and accumulation by bovine chondrocytes in three‐dimensional culture
Authors: Mizuno Shuichi , Tateishi Tetsuya , Ushida Takashi , Glowacki Julie 
Published: October 2002

AbstractMonolayer cell cultures and cartilage tissue fragments have been used to examine the effects of hydrostatic fluid pressure (HFP) on the anabolic and catabolic functions of chondrocytes. In this study, bovine articular chondrocytes (bACs) were grown in porous three‐dimensional (3‐D) collagen sponges, to which constant or cyclic (0.015 Hz) HFP was applied at 2.8 MPa for up to 15 days. The effects of HFP were evaluated histologically, immunohistochemically, and by quantitative biochemical measures. Metachromatic matrix accumulated around the cells within the collagen sponges during the culture period. There was intense intracellular, pericellular, and extracellular immunoreactivity for collagen type II throughout the sponges in all groups. The incorporation of [35S]‐sulfate into glycosaminoglycans (GAGs) was 1.3‐fold greater with constant HFP and 1.4‐fold greater with cyclic HFP than in the control at day 5 (P < 0.05). At day 15, the accumulation of sulfated‐GAG was 3.1‐fold greater with constant HFP and 2.7‐fold with cyclic HFP than the control (0.01). Quantitative immunochemical analysis of the matrix showed significantly greater accumulation of chondroitin 4‐sulfate proteoglycan (C 4‐S PG), keratan sulfate proteoglycan (KS PG), and chondroitin proteoglycan (chondroitin PG) than the control (P < 0.01). With this novel HFP culture system, 2.8 MPa HFP stimulated synthesis of cartilage‐specific matrix components in chondrocytes cultured in porous 3‐D collagen sponges. J. Cell. Physiol. 193: 319–327, 2002. © 2002 Wiley‐Liss, Inc.
Are there gap junctions between chief (glomus, type I) cells in the carotid body chemoreceptor? A review
Authors: Kondo Hisatake 
Published: October 2002

AbstractSince the dye‐ and electronic couplings between the carotid body chief cells have been demonstrated, the detection and localization of the gap junctions in the carotid body is crucial to understanding the functional mechanism of chemoreception. However, conventional electron microscopy has been unsuccessful in unquestionably detecting ultrastructural features equivalent to the gap junctions, such as close (2 nm in width) membrane appositions in ultrathin sections and aggregations of intramembranous particles in freeze‐fracture replicas of the carotid body. We previously reported using a modified electron microscopic study by chemically fixed and subsequent rapid freezing and freeze‐substitution method a number of close membrane appositions comparable to the gap junctions. However, we later found that the freeze‐substitution also induces numerous close apposition of the membrane in sites where the gap junctions are not known to occur, indicating that the modified electron microscopy by freeze‐substitution is not always confirmative in the detection of the gap junction. With regard to the molecular evidence for the gap junction in the carotid body, there have so far been few data on the immunohistochemical demonstration on connexin 32 and 43 in cultured chief cells, but not in the in situ cells. Microsc. Res. Tech. 59:227–233, 2002. © 2002 Wiley‐Liss, Inc.
Relative messenger RNA expression profiling of collagenases and aggrecanases in human articular chondrocytes in vivo and in vitro
Authors: Bau Brigitte , Gebhard Pia M. , Haag Jochen , Knorr Thomas , Bartnik Eckart , Aigner Thomas 
Published: October 2002

AbstractObjectiveOsteoarthritic (OA) cartilage destruction depends on collagen‐ and aggrecan‐degrading proteases such as collagenases (MMP‐1 and MMP‐13), stromelysin (MMP‐3), MMP‐14, as well as the so‐called aggrecanases (ADAM‐TS4 and ADAM‐TS5). In this study, we tried to clarify whether these proteases are expressed in vivo in human normal and OA cartilage (and whether they are up‐regulated or down‐regulated during the disease process) and in interleukin‐1β (IL‐1β)–stimulated chondrocytes in vitro.MethodsQuantitative polymerase chain reaction assays were developed and performed on RNA isolated directly from normal and degenerative cartilage tissue as well as from primary human articular chondrocytes cultured with and without IL‐1β.ResultsIn vivo, MMP‐1 was detectable only at very low levels in any condition. MMP‐13 expression was low in normal and early degenerative cartilage but was strongly up‐regulated in late‐stage OA specimens. MMP‐1 and MMP‐13 were expressed much higher in vitro than in vivo and were up‐regulated by IL‐1β. Among all proteases, MMP‐3 was by far the most strongly expressed, although it was strongly down‐regulated in late‐stage OA specimens. Expression of MMP‐3 was higher in vitro than in vivo and was up‐regulated by IL‐1β. ADAM‐TS5 and MMP‐14 were expressed in all sample groups. Expression of ADAM‐TS4 was very low in vivo and was induced in vitro after stimulation by IL‐1β.ConclusionOur expression data clearly support MMP‐13 as the major collagenase in OA cartilage. The most strongly expressed aggrecanase was ADAM‐TS5. ADAM‐TS4 was expressed only at a very low level in normal cartilage and was only slightly up‐regulated in OA cartilage, casting doubt on this enzyme being the relevant aggrecanase of articular cartilage. Results of our study show that expression of many enzymes is significantly different in vitro and in vivo and suggest that IL‐1β stimulation of articular chondrocytes might not be a good model for the matrix catabolism in OA cartilage.
MAC over ATM group communication system
Authors: Hayase Kazuyoshi , Irie Kazunari , Ohta Norihisa 
Published: October 2002

AbstractThe authors propose a regional information network system that provides communications among the group members using personal computers (PC). In order to cope with the future requirements for high‐speed communication, there must be a system that can achieve diversified communication rates and accommodate a large number of users. From such a viewpoint, this paper considers the composition of a new system based on the MAC over ATM scheme. As the first step, systems based on existing techniques are presented: a system (MAC terminating system) to which the transition from the STM system is easy, and a system (LANE system) based on the LAN emulation standard. Then, a new system (BC‐VC) is proposed, in which the processing in the center is realized only by the ATM layer. Those systems are compared and examined by simulation, and it is shown that the BC‐VC system is better than the other systems when there is a large number of groups. Furthermore, the design of an experimental system based on the BC‐VC scheme is shown, together with the results of performance evaluation experiments. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 86(2): 61–70, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1154
Calculation of normalized impedance of a transversal slot on the image plate of an image NRD guide using the method of moments
Authors: Ishii Nozomu , Itoh Kiyohiko 
Published: October 2002

AbstractThe normalized impedance of a transverse slot on the image plate of an image NRD that is a modification of the original NRD is formulated by means of the method of moments. In terms of the modes that can be supported within the image NRD guide, the electromagnetic field inside the guide is modally expanded and the dyadic Green's function (DGF) is obtained. In addition, by applying the concept of the virtual cavity method, the DGF is modified. The numerical results are compared with the experimental data obtained by the standing wave measurement method. The difference in the resonant frequency is 1.6% and a shift of the peak value is observed. Nevertheless, the tendencies of the frequency locus are identical. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 86(2): 71–79, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1155
Analysis and simulation of received signal level distribution in wide‐band mobile radio channels
Authors: Yan Jiang , Kozono Shigeru 
Published: October 2002

AbstractThis paper considers the propagation model in which the amplitude of the direct wave is kept constant and that of the indirect wave exhibits Rayleigh fluctuations in the line‐of‐sight and non‐line‐of‐sight channels. The instantaneous received signal level distribution is examined by computer simulation and a fading simululator, with the equivalent received bandwidth (product of received bandwidth 2Δf and maximum path length difference ΔLmax) as the propagation parameter. It is seen that the equivalent received bandwidth is suited as a parameter to represent the instantaneous received signal level distribution. The instantaneous received signal level distributions derived by the computer simulation and the fading simulator agree well. Conventional narrow‐band transmission corresponds to the case in which 2ΔfΔLmax is less than 10 MHz‐m. Then, the fading depth is determined by the power ratio a between the direct wave and the indirect wave. Wide‐band transmission corresponds to the case in which 2ΔfΔLmax is larger than 10‐MHz‐m. Then, the fading depth is determined by a and 2ΔfΔLmax, becoming less when those quantities are increased. When 2ΔfΔLmax is very large, the fading depth also depends on the number of arriving waves. These properties are derived theoretically and are verified by the simulation and the fading simulator. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 86(2): 94–105, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.1157
Two‐dimensional modelling of ice cover effects for the dynamic analysis of concrete gravity dams
Authors: Bouaanani Najib , Paultre Patrick , Proulx Jean 
Published: October 2002

AbstractA two‐dimensional numerical model for determining the effects of the presence of an ice cover on the dynamic behaviour of large gravity dams is presented. Analytical predictions are compared to results obtained during a series of extensive dynamic tests on a large gravity dam. Data were obtained during summer and severe winter conditions to investigate the dynamic interactions between the dam, foundation, reservoir and the ice cover. The analysis includes ice‐reservoir interaction as well as the effects of water compressibility, flexible foundation and reservoir bottom absorption. Good agreement with the experimental findings is obtained. Copyright © 2002 John Wiley & Sons, Ltd.
Ascertainment adjustment in complex diseases
Authors: Glidden David V. , Liang Kung‐Yee 
Published: October 2002

AbstractGenetic studies of complex diseases must confront two statistically difficult issues simultaneously. First, in many settings, to minimize the number of individuals to be genotyped, families enriched for disease must be oversampled. Also, statistical models in family studies should allow for residual association. This association will represent unmeasured genetic and environmental factors influencing disease risk. Dealing with these features simultaneously is both compelling and challenging. Burton et al. [2000] (Am. J. Hum. Gen. 69: 1505–14) recently discussed this issue and suggested that ascertainment corrections may lead to problematic parameter estimation. We revisit the issues and examples of Burton et al. [2000] (Am. J. Hum. Genet. 69: 1505–14) and present a more optimistic assessment. Estimation in this context is conceptually straightforward, but may be more problematic in practice. Specifically, we find that even slight misspecification of the random effects distribution in ascertainment‐adjusted likelihood can yield severely biased parameter estimates. This result should make scientists wary when interpreting results from ascertainment‐adjusted variance‐component models. Genet. Epidemiol. 23:201–208, 2002. © 2002 Wiley‐Liss, Inc.
A fast simulation model combining with artificial neural networks for fin‐and‐tube condenser
Authors: Ding Guo‐liang , Zhang Chun‐lu , Liu Hao 
Published: October 2002

AbstractIn order to improve predicting precision and increase the computation speed of simulation for a fin‐and‐tube condenser, a novel method integrating the fundamental mathematical model with an artificial neural network (ANN) is presented. A three‐zone model is used as the basic mathematical model. An ANN maps the nonlinear relation between the distributed‐parameter model and the three‐zone one. Another ANN is involved in the present model to reflect the bias between the model and experimental results, and to improve the simulation accuracy. Practical utilization of the present model shows that the computation speed of the present model is two orders of magnitude higher than that of the distributed‐parameter model, while the precision is also improved. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(7): 551–557, 2002; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/htj.10054
Heat transfer research on vapor‐gas mixture with condensation in a vertical tube
Authors: Jia L. , Li X.P. , Sun J.D. 
Published: October 2002

AbstractThe convection‐condensation heat transfer of vapor‐gas mixtures in a vertical tube was studied theoretically and experimentally. The effects of the condensation of a small amount of water vapor (8 to 20%) on heat transfer in a vertical tube were discussed. Comparisons show that theoretical solutions obtained through modified film model and experimental results are in good agreement. The results show that the condensation heat transfer of a small amount of water vapor and single‐phase convection heat transfer in the vapor‐gas mixtures are of the same order of magnitude, and these two modes of heat transfer could not be neglected. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(7): 531–539, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10055
A finite line‐source model for boreholes in geothermal heat exchangers
Authors: Zeng H. Y. , Diao N. R. , Fang Z. H. 
Published: October 2002

AbstractAn analytical solution of the transient temperature response in a semi‐infinite medium with a line source of finite length has been derived, which is a more appropriate model for boreholes in geothermal heat exchangers, especially for their long‐duration operation. The steady‐state temperature distribution has also been obtained as a limit of this solution. An erratic approach to this problem that appears in some handbooks and textbooks is indicated. Two representative steady‐state borehole wall temperatures, the middle point temperature and the integral mean temperature, are defined. Differences between them are compared, and concise expressions for both are presented for engineering applications. On this basis the influence of the annual imbalance between heating and cooling loads of the geothermal heat exchangers is discussed regarding their long‐term performance. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(7): 558–567, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10057
Temperature fluctuation in bubble nucleate pool boiling: A proposed new factor of evaporation
Authors: Sekine Ikuhei 
Published: October 2002

AbstractThe phase change rate and related physical constants of superheated water at the liquid surface can be determined by the mechanism of hydrogen bonding and by the Maxwell‐Boltzmann principle. In this paper, we introduce a physical constant and attempted to demonstrate the existence and the value of this physical constant. First, we measured temperature fluctuations under the bubbles in a pool of boiling water. Second, a sample analytical model was introduced, to determine the value of the physical constant. Comparisons were made between the experimental data and those of the calculations. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(7): 578–594, 2002; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/htj.10059
Retinoic acid induces expression of the interleukin‐1β gene in cultured normal human mammary epithelial cells and in human breast carcinoma lines
Authors: Liu Limin , Gudas Lorraine J. 
Published: October 2002

AbstractRetinoic acid (RA) and its derivatives inhibit the proliferation of normal human mammary epithelial cells (HMEC) and some breast carcinoma lines by mechanisms which are not fully understood. To identify genes that mediate RA‐induced cell growth arrest, an HMEC cDNA library was synthesized and subtractive screening was performed. We identified the interleukin‐1β (IL‐1β) gene as an RA induced gene in HMEC. Northern blot analyses showed that the IL‐1β gene was up‐regulated as early as 2 h after RA treatment. Results from the treatment of HMEC with cycloheximide and actinomycin D indicated that the regulation of the IL‐1β gene by RA occurred at the transcriptional level and that the IL‐1β gene is a direct, downstream target gene of RA. To evaluate the effects of IL‐1β on cell proliferation, the proliferation of HMEC was measured in the presence of RA or IL‐1β, or both. Either RA or IL‐1β could significantly inhibit the proliferation of HMEC. However, the addition of soluble IL‐1 receptor antagonist (sIL‐1ra) to the cell culture medium did not block RA‐induced HMEC growth inhibition, whereas sIL‐1ra did block the growth inhibition of HMEC by IL‐1β. IL‐1β expression was not observed in the three carcinoma cell lines, MCF‐7, MDA‐MB‐231, and MDA‐MB‐468, as compared to the HMEC. Growth curves of the breast carcinoma cell lines showed strong inhibitory effects of RA and IL‐1β on the growth of the estrogen receptor (ER) positive MCF‐7 cell line, but only a small effect on the ER negative MDA‐MB‐231 cells. The expression of the IL‐1β gene was also transcriptionally activated by RA in normal epithelial cells of prostate and oral cavity. Our results suggest that: (a) the IL‐1β gene is a primary target of RA receptors in HMEC; (b) the enhanced expression of the IL‐1β gene does not mediate the RA‐induced growth arrest of HMEC; and (c) the expression of the IL‐1β gene is low or absent in all three human breast carcinoma cell lines examined, but the defect in the IL‐1β signaling pathway may be different in ER positive versus ER negative carcinoma cells. © 2002 Wiley‐Liss, Inc.
Pathophysiologic role of myocardial apoptosis in post‐infarction left ventricular remodeling
Authors: Abbate Antonio , Biondi‐Zoccai Giuseppe GL , Baldi Alfonso 
Published: October 2002

AbstractLeft ventricular (LV) remodeling and heart failure (HF) complicate acute myocardial infarction (AMI) even weeks to months after the initial insult. Apoptosis may represent an important pathophysiologic mechanism causing progressive myocardiocyte loss and LV dilatation even late after AMI. This review will discuss the role of apoptosis according to findings in animal experimental data and observational studies in humans in order to assess clinical relevance, determinants, and mechanisms of myocardial apoptosis and potential therapeutic implications. More complete definition of the impact of myocardiocyte loss on prognosis and of the mechanisms involved may lead to improved understanding of cardiac remodeling and possibly improved patients' care. Mitochondrial damage and bcl‐2 to bax balance play a central role in ischemia‐dependent apoptosis while angiotensin II and β1‐adrenergic‐stimulation may be major causes of receptor‐mediated apoptosis. Benefits due to treatment with ACE‐inhibitors and β‐blockers appear to be in part due to reduced myocardial apoptosis. Moreover, infarct‐related artery patency late after AMI may be a major determinant of myocardial apoptosis and clinical benefits deriving from an open artery late post AMI (the “open artery hypothesis”) may be, at least in part, due to reduced myocardiocyte loss. © 2002 Wiley‐Liss, Inc.
Spontaneous dehydration mechanism of aromatic aldehyde reactions with hydroxyl and non‐hydroxyl amines
Authors: Travalon Silvana Azzolini , Brighente Inês Maria Costa , Yunes Rosendo Augusto 
Published: October 2002

AbstractThe plot of rate constants vs. pH for the dehydration step of the reaction between furfural and 5‐nitrofurfural with hydroxylamine, N‐methylhydroxylamine, and O‐methylhydroxylamine, shows two regions corresponding to the oxonium ion‐catalyzed and spontaneous dehydration. The oxonium ion‐catalyzed dehydration region of the reaction of furfural with the above mentioned hydroxylamines exhibits general acid catalysis with excellent Brønsted correlation (Brønsted coefficients: 0.76 (r = 0.986), 0.68 (r = 0.987), and 0.67 (r = 0.993) respectively). However, the rate constants of the spontaneous dehydration of these hydroxylamines, where water is considered the general acid catalyst, exhibit a large positive deviation from the Brønsted line. This fact was not observed in the reaction of non‐hydroxyl amines with different aromatic aldehydes by other authors, thus supporting that the spontaneous dehydration steps for these reactions proceed by intramolecular catalysis. The mechanism of intramolecular catalysis might be stepwise. First, a zwitterionic intermediate is formed. It can then evolve in the second step by loss of water, or follow a concerted pathway, with the transference of a proton through a five‐membered ring (general intramolecular acid catalysis). In the case of non‐hydroxyl amines, data suggested the possibility of a mechanism of intramolecular proton transfer through one or two water molecules, from the nitrogen of the amine to the leaving hydroxide ion. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 685–692, 2002
Output regulation of general discrete‐time linear systems with saturation nonlinearities
Authors: Hu Tingshu , Lin Zongli 
Published: October 2002

AbstractThis paper studies the classical problem of output regulation for linear discrete‐time systems subject to actuator saturation and extends the recent results on continuous‐time systems to discrete‐time systems. The asymptotically regulatable region, the set of all initial conditions of the plant and the exosystem for which the asymptotic output regulation is possible, is characterized in terms of the null controllable region of the anti‐stable subsystem of the plant. Feedback laws are constructed that achieve regulation on the asymptotically regulatable region. Copyright © 2002 John Wiley & Sons, Ltd.