bluuebunny/crossref_metadata_2025 huggingface dataset:
A method combining error correcting code and runlength limited code for reducing error propagation
Authors: Hirai Tadamitsu , Wadayama Tadashi , Yuba Yoshiharu
Published: August 2002

In this paper we discuss a method for reducing the error propagation based on a combination of the error correcting code and the runlength limited code. When the runlength limited code and the error correcting code are used together, the runlength limited encoding is usually applied after the data have been encoded by the encoder of the error correcting code. However, error propagation generated in the data transmission channel can be substantially mitigated during the decoding of the runlength limited code if the runlength encoding is implemented first with subsequent implementation of the error correcting code. The method proposed in this paper consists of a periodic insertion of check symbols in the data sequence encoded first by the runlength limited code and then by the error correcting code. We also proposed a new runlength limited code suitable for the proposed combined method and evaluated its performance. © 2001 Scripta Technica, Electron Comm Jpn Pt 3, 84(11): 45–51, 2001
Improving the performance analysis of a gradient‐based adaptive IIR notch filter
Authors: Takeshita Yoshihiro , Xiao Yegui , Shida Katsunori
Published: August 2002

Improvement of performance analysis is discussed for the plain gradient‐type adaptive IIR bilinear notch filters often used in the areas of communication, control, radar, and so on. Specifically, instead of the gradient linearization in the conventional analysis, nonlinear terms are introduced in the approximate expression of the gradient and an explicit expression of the estimation variance of the gradient algorithm in the steady state is derived. In regard to the step size, the convergence condition is derived that guarantees convergence of the algorithm. Its effectiveness and limitation are clarified. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 85(9): 25–34, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.1116
Compensation for neutral point potential in a three‐level inverter using motor currents of a permanent magnet synchronous motor and its characteristics
Authors: Shinohara Katsuji , Sakasegawa Eiichi
Published: August 2002

A three‐level inverter has several advantages of large capacity, large voltage, and low current waveform distortion. However, there is an important problem of neutral point potential variation in three‐level inverters. The variation causes an unbalance in the dc link voltage levels and current waveform distortion. In this paper, we propose a new method to control the neutral point potential. First, the neutral point potential variation in a three‐level inverter for permanent magnet synchronous motor drive is analyzed by state variable method and is calculated on the basis of the analytic results. Second, using the estimated value, proposed compensation for the variation can be done. Third, analytic and experimental results of the proposed method are compared with the results of feedforward compensation by simply adjusting the vector output intervals. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 139(4): 56–63, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10033
Stabilization for thermomagnetic instability of CuNi/NbTi superconducting wire in spatially distributed magnetic field
Authors: Banno Nobuya , Amemiya Naoyuki
Published: August 2002

Thermomagnetic instability in superconducting wires composing multistrand cables is a problem in the development of cables with large current capacity. This paper elucidates the quenching properties of ac superconducting wires in a distributed magnetic field applied to the strands in the cable, and the stabilization of the ac superconducting wires considering the effect of the longitudinal magnetic field or the fraction of copper embedded in each strand. First, the degradation of the quench current of CuNi/NbTi superconducting wires in a distributed magnetic field is exhibited with simple test samples. Second, the quench properties of the strand in a (6 + 1)3 cable and the optimal twist pitch of the cable for high stabilization are discussed. Last, the effect of copper on the quench properties of the strand and the appropriate fraction of copper for suppression of quench current degradation in a distributed magnetic field are discussed. © 2001 Scripta Technica, Electr Eng Jpn, 135(4): 26–34, 2001
A study of the normalized LMS method with threshold
Authors: Tanpreeyachaya Jirasak , Nakanishi Takahiro , Usuda Tsuyoshi , Takumi Ichi , Hata Masayasu
Published: August 2002

In this paper, we study a modified normalized least mean square (NLMS) algorithm for updating coefficients of an adaptive FIR digital filter (ADF). In the modified adaptive algorithm, filter coefficients are updated with the NLMS algorithm for each sample, but the coefficients are frozen when the input signal is smaller than a given threshold (constant). This modified NLMS has been known, but not been analyzed.

In this paper, we call the modified NLMS the “conditioned NLMS” (C‐NLMS) and analyze the convergence characteristics. As a result, the optimum threshold value is obtained. The simulation results and theoretical analyses show the effectiveness of the C‐NLMS with the proposed threshold, and a good agreement between both results. The stability of the NLMS algorithm in the presence of a small input signal is improved. The convergence speed of the C‐NLMS ADF under noisy circumstances is also faster than that of the unconditioned ordinary NLMS ADF in the small tap number case. © 2001 Scripta Technica, Electr Eng Jpn, 136(4): 47–57, 2001
A consideration of potentials of low‐density polyethylene using metallocene catalyst as insulator for power cable
Authors: Cho Don‐Chan , Ishii Ryousuke , Shizu Keiichiro , Semi Hitoshi , Mori Tatsuo , Mizutani Teruyoshi , Ishioka Mitsugu
Published: August 2002

We investigated the high‐field conduction, DC and impulse breakdown strength, space charge distribution, and tree inception voltage for three kinds of new low‐density polyethylene (LDPE) prepared using a metallocene catalyst (mLna, mLao, mLldao), linear LDPE prepared using a Ziegler catalyst (LLao), and LDPE prepared by a high‐pressure process (LDna). The dc and impulse breakdown strengths of LDPEs prepared using a metallocene catalyst were higher than those of LLao and LDna. The high‐field currents of LDPEs prepared using a metallocene catalyst were lower than those of LLao and LDna. A homo‐space charge was accumulated near the cathode in mLna. The tree inception voltage of mLna was higher than that of LDna. From these results, it is concluded that LDPE prepared using a metallocene catalyst has electrical insulating properties superior to the conventional LDPE and that the former has potential as a power cable insulator. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 139(4): 17–25, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.1164
Realization of a multiport gyrator using current mirror circuits
Authors: Kubota Kenichi , Okine Mitsuo
Published: August 2002

A current‐mode signal processing circuit is quite attractive for low supply voltage operation and high‐frequency application. A current‐mode continuous‐time filter consists of simple bipolar current mirrors and capacitors, and are quite suitable for monolithic integration. In this paper, we propose a design for a multiport gyrator using current mirror circuits. Using the multiport gyrator and capacitors, we can simulate passive LC filters. The tuning of the filter frequency can be achieved by adjusting the current of a single dc current course. As examples, third‐ and fifth‐order low‐pass filters are designed for frequencies of 20 to 80 MHz, and SPICE simulation results are shown to demonstrate the effectiveness of the proposed method. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 139(4): 41–47, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.1167
Modulation of streptonigrin's clastogenic effects in CHO cells by the metal‐chelating agent 1,10‐phenanthroline
Authors: Bolzán Alejandro D. , Bianchi Martha S. , Correa María V.
Published: August 2002

The effect of the metal‐chelating agent 1,10‐phenanthroline (PNT) on the clastogenesis induced by streptonigrin (SN) in CHO cells was investigated. When CHO cells were exposed to SN, chromosomal aberrations (CAs) and sister‐chromatid exchanges (SCEs) were formed in a dose‐dependent manner (P < 0.05). When PNT was present in the culture medium, the production of CAs by SN was strongly inhibited (inhibition range = 54.9–80.8%). Similarly, the induction of SCEs by SN was significantly decreased by the addition of PNT to CHO cultures (P < 0.05), although the effect was minor. This finding suggests that intracellular transition metals are implicated in the clastogenesis by SN, and that the Fenton reaction (Fe2+ + H2O2 → OH* + OH− + Fe3+) may be responsible for the production of CAs by this compound. Moreover, the fact that PNT did not completely inhibit the induction of SCEs by SN suggests that this phenomenon might be attributable to a different mechanism, in which transition metals and free radicals play a minor role. Environ. Mol. Mutagen. 38:306–310, 2001. © 2001 Wiley‐Liss, Inc.
Statistical issues on the determination of the no‐observed‐adverse‐effect levels in toxicology
Authors: Yanagawa Takashi , Kikuchi Yasuki
Published: August 2002

The determination of a safe exposure level for toxic agents, often defined as the highest dose level with no toxic effect and termed the no‐observed‐adverse‐effect level (NOAEL) is reviewed. The conventional methods based on statistical tests are criticized, particularly when the sample size is small, and an alternative method, which is based on the Akaike information criterion (AIC), is discussed. The method is extended to the estimation of the NOAEL for continuous data. Computer programs for Windows 95/NT for determining the NOAEL by the AIC approach are developed and its application to practical data is illustrated with examples. Copyright © 2001 John Wiley & Sons, Ltd.
Bayesian hierarchical generalized linear models for a geographical subset of recovery data
Authors: Cocchi Daniela , Trivisano Carlo
Published: August 2002

The aim of this work is to check whether modifications in the length of the hunting seasons had an effect on the chance of reproduction of different species of ringed birds. We start from a national data set of ringing‐recovered data on three species of game birds. Only data on birds recovered as juveniles are used. Data on recoveries are organized in a 4‐way contingency table. Several generalized linear models are proposed for the counts of recovered birds. Bayesian hierarchical modeling is particularly suitable for this kind of data, for which an over‐dispersion parameter can be introduced at the second level of the hierarchy. Maximum Likelihood and Bayesian solutions are computed for the different models: the Bayesian framework, in particular under an individual modeling of over‐dispersion, exhibits the best fit in terms of Bayesianp‐value. The results show that the modification in the length of the hunting seasons does not produce equal benefits for the three species considered. Copyright © 2002 John Wiley & Sons, Ltd.
Evaluation of approximate methods to estimate maximum inelastic displacement demands
Authors: Miranda Eduardo , Ruiz‐García Jorge
Published: August 2002

Six approximate methods to estimate the maximum inelastic displacement demand of single‐degree‐of‐freedom systems are evaluated. In all methods, the maximum displacement demand of inelastic systems is estimated from the maximum displacement demand of linear elastic systems. Of the methods evaluated herein, four are based on equivalent linearization in which the maximum deformation is estimated as the maximum deformation of a linear elastic system with lower lateral stiffness and with higher damping coefficient than those of the inelastic system. In the other two methods the maximum inelastic displacement is estimated as a product of the maximum deformation of a linear elastic system with the same lateral stiffness and the same damping coefficient as those of the inelastic system for which the maximum displacement is being estimated, times a modifying factor. Elastoplastic and stiffness‐degrading models with periods between 0.05 and 3.0 s are considered when subjected to 264 ground motions recorded on firm sites in California. Mean ratios of approximate to exact maximum displacements corresponding to each method are computed as a function of the period of vibration and as a function of the displacement ductility ratio. Finally, comments on the advantages and disadvantages of each method when applied to practical situations are given. Copyright © 2001 John Wiley & Sons, Ltd.
A new method for non‐stationary random critical excitation
Authors: Takewaki Izuru
Published: August 2002

Since earthquake ground motions are very uncertain even with the present knowledge, it is desirable to develop a robust structural design method taking into account these uncertainties. Critical excitation approaches are promising and a new non‐stationary random critical excitation method is proposed. In contrast to the conventional critical excitation methods, a stochastic response index is treated as the objective function to be maximized. The power (area of power spectral density (PSD) function) and the intensity (magnitude of PSD function) are fixed and the critical excitation is found under these restrictions. It is shown that the original idea for stationary random inputs can be utilized effectively in the procedure for finding a critical excitation for non‐stationary random inputs. The key for finding the new non‐stationary random critical excitation is the exchange of the order of the double maximization procedures with respect to time and to the power spectral density function. Copyright © 2001 John Wiley & Sons, Ltd.
Effects of spatial variations in source areas upon dust concentration profiles during three wind erosion events in Australia
Authors: Butler H. J. , Hogarth W. L. , McTainsh G. H.
Published: August 2002

Dust storms are a major contributor to soil erosion in inland Australia, and the Simpson Desert–Channel Country region is one of the most active wind erosion regions. While information is available on wind erosion rates at the land‐type level, little is known about the influence that spatial variations in the erodibility within a land type have on the resulting dust concentration profile. A Gaussian plume model, DSIS, is presented along with tower‐based dust data, to describe the influence of different spatial combinations of dust source areas, during three dust events on the Diamantina River floodplain in Western Queensland, Australia. Copyright © 2001 John Wiley & Sons, Ltd.
Continuing use of low‐income services by former Missouri welfare recipients
Authors: Dunton Nancy , Mosley Jane , Butcher, Lola
Published: August 2002

This chapter examines the degree of self‐sufficiency and the need for sustained income supports among leavers in Missouri.
Reliable component identification in atmospheric open‐path FTIR spectroscopy by a cross‐correlation method
Authors: Müller Uwe , Heise H. Michael
Published: August 2002

Continuous environmental air monitoring is possible with open‐path FTIR spectroscopy. Efficient chemometric tools are needed for the identification of unknown compounds that are observable in remote sensing of volatile emissions into the atmosphere. A qualitative analysis using spectra recorded at a resolution of 0.2 cm−1is proposed, based on the cross‐correlation function and calculated with data from component‐specific intervals from library absorbance spectra. The characteristic wave‐number intervals were selected on the grounds of the most intense component absorption bands for which negligible overlap was present with atmospheric absorption lines. The algorithm has been implemented for 36 different gaseous substances into an expert system for the evaluation of atmospheric FTIR spectra, recorded for routine work in active open‐path monitoring. Detection limits for substance identification from mixture spectra are discussed. The influence from overlapping spectral features of co‐existing atmospheric compounds can be reduced by preprocessing, including such techniques as scaled absorbance subtraction with appropriate spectra of the known gases. A discussion of identification strategies previously presented in the literature is included. © 2001 John Wiley & Sons, Inc. Field Analyt Chem Technol 5: 50–59, 2001
Backhousia citriodora F. Muell.—Rediscovery and chemical characterization of the L‐citronellal form and aspects of its breeding system
Authors: Doran J. C. , Brophy J. J. , Lassak E. V. , House A. P. N.
Published: August 2002

The rare L‐citronellal form of Backhousia citriodora F. Muell. was first reported in 1950 but attempts to relocate it were unsuccessful until 1996. The quest to relocate trees of this type has been driven by interest in L‐citronellal for perfumery. The common, citral form of the species is already under cultivation for oil production in Australia. This paper reports on the rediscovery of the L‐citronellal form, first in 1996 in a year‐old provenance/progeny trial of B. citriodora in south‐eastern Queensland, and then in a natural population on Queensland's Sunshine Coast in 1998. The three L‐citronellal trees in the trial gave foliar oil concentrations (g/100 g dry weight) of 3.2, 2.2 and 1.8, respectively, when sampled in November 1996. The same trees sampled in March 1999 gave pale yellow oils consisting of 85–89% citronellal, 6–9% isopulegol isomers with small quantities of citronellol (approx. 3%) and several other compounds. Data on the physicochemical properties of these oils are given in the paper. Seed from a single mature L‐citronellal tree gave progeny of both the L‐citronellal and citral form in a ratio of approximately 1 : 1. Propagation material from many more plants of the L‐citronellal form needs to be collected and assembled in breeding populations. This would form the basis of a selection and breeding programme, should this chemotype show economic potential. Copyright © 2001 John Wiley & Sons, Ltd.
Characterization of an Italian biotype of clary sage (Salvia sclarea L.) grown in a semi‐arid Mediterranean environment
Authors: Carrubba A. , la Torre R. , Piccaglia R. , Marotti M.
Published: August 2002

An Italian spontaneous biotype of clary sage (Salvia sclarea L.) was evaluated for its suitability to be cultivated in a semi‐arid area and for the influence of these growth conditions on the essential oil composition. Seeds gathered from a spontaneous biotype were sown directly in the field, using a seeding density calculated to achieve a plant population of 7 plants/m2. Essential oils from the inflorescences and leaves of plants harvested at full flowering and early seed ripeness stages were obtained by steam distillation and characterized by GC and GC–MS. The plants showed a good tolerance to the semi‐arid growth conditions, yielding more than 700 flowers/plant and about 21 g seeds/plant. Relevant qualitative and quantitative differences were detected between the essential oils from the inflorescences and leaves, the former being characterized by a high content of linalool (26–29%) and linalyl acetate (35–53%) and the latter only by sesquiterpenes, with germacrene D as the main compound (68–69%). Inflorescences at full flowering stage were richer in linalool, α‐terpineol and germacrene D, showing a lower content in linalyl acetate in comparison with those collected at early seed ripeness. The development stage did not influence the oil composition of leaves. Copyright © 2002 John Wiley & Sons, Ltd.
Choosing among competing econometric forecasts: Regression‐based forecast combination using model selection
Authors: Swanson Norman R. , Zeng Tian
Published: August 2002

Forecast combination based on a model selection approach is discussed and evaluated. In addition, a combination approach based on ex ante predictive ability is outlined. The model selection approach which we examine is based on the use of Schwarz (SIC) or the Akaike (AIC) Information Criteria. Monte Carlo experiments based on combination forecasts constructed using possibly (misspecified) models suggest that the SIC offers a potentially useful combination approach, and that further investigation is warranted. For example, combination forecasts from a simple averaging approach MSE‐dominate SIC combination forecasts less than 25% of the time in most cases, while other ‘standard’ combination approaches fare even worse. Alternative combination approaches are also compared by conducting forecasting experiments using nine US macroeconomic variables. In particular, artificial neural networks (ANN), linear models, and professional forecasts are used to form real‐time forecasts of the variables, and it is shown via a series of experiments that SIC, t‐statistic, and averaging combination approaches dominate various other combination approaches. An additional finding is that while ANN models may not MSE‐dominate simpler linear models, combinations of forecasts from these two models outperform either individual forecast, for a subset of the economic variables examined. Copyright © 2001 John Wiley & Sons, Ltd.
Duplication or amplification of chromosome band 11q23, including the unrearranged MLL gene, is a recurrent abnormality in therapy‐related MDS and AML, and is closely related to mutation of the TP53 gene and to previous therapy with alkylating agents
Authors: Andersen Mette K. , Christiansen Debes H. , Kirchhoff Maria , Pedersen‐Bjergaard Jens
Published: August 2002

Gene amplification is a rare phenomenon in acute leukemia, but recently amplification of specific chromosome bands containing genes rearranged in leukemia‐specific balanced chromosome translocations has been reported in a few cases. We detected duplication or amplification of chromosome band 11q23 with 3–7 copies of the MLL gene by fluorescence in situ hybridization in 12 out of 70 unselected patients with therapy‐related myelodysplasia or acute myeloid leukemia (17%). In all but one case, the supernumerary copies of MLL were located to previously unidentified marker chromosomes or unbalanced translocations. In 4 of the 12 patients, 2–6 copies were located together on the same chromosome arm representing amplification, 7 patients had single, extra duplicated copies of MLL, whereas both amplification and duplication were observed in the same cell in 1 patient. Comparative genomic hybridization demonstrated gain of varying, often large parts of 11q in five patients. The MLL gene was shown to be unrearranged in all 12 patients. Seven out of eight patients with duplication or amplification of MLL had mutations of TP53. Patients with supernumerary copies of MLL were in general older (P = 0.007) and had a shorter survival (P < 0.001) compared to other patients. Duplication or amplification of MLL was significantly associated with a complex karyotype (P = 0.002), with deletion or loss of 5q (P = 0.001), and with prior therapy with alkylating agents. These results support the existence of a specific genetic pathway in t‐MDS and t‐AML with many previously unidentified chromosome aberrations demonstrated to represent extra copies of parts of 11q, including the unrearranged MLL gene. © 2001 Wiley‐Liss, Inc.
Gain of 1q and loss of 9q21.3‐q32 are associated with a less favorable prognosis in papillary thyroid carcinoma
Authors: Kjellman Petra , Lagercrantz Svetlana , Höög Anders , Wallin Göran , Larsson Catharina , Zedenius Jan
Published: August 2002

In order to approach the genetic mechanisms behind initiation and progression of papillary thyroid carcinoma (PTC) tumorigenesis, we characterized numerical chromosomal imbalances in a panel of 25 PTCs with varying histopathological and clinical features using comparative genomic hybridization (CGH). The most frequently detected imbalance was gain of 9q33‐qter, which was seen in close to 30% of the cases. The commonly occurring regions of loss were assigned to 22q (12%) and 9q21.3‐q32 (12%), while gains preferentially involved the entire X chromosome (20%), 1q (16%), 17q (16%), and 22q (12%). The distribution of CGH alterations supports the idea of a progression of genetic events in the development of PTC, where gain of 9q33‐qter would represent a relatively early event that is followed by loss of 22q and gain of X, 1q, 17q, and 22q. When the detected CGH alterations were compared with the clinical outcome and the histopathological features of the 25 PTC cases, several statistically significant correlations were revealed. The total number of genetic alterations was higher in tumors from patients with aggressive disease as compared to those without signs of aggressiveness. Gain of 1q and loss of 9q21.3‐q32 were exclusively seen in tumors from patients with aggressive disease, and the presence of distant metastases was associated with gain of 1q. A sex‐dependent distribution was also evident for one of the common alterations, with gain of X exclusively seen in male cases. Taken together, the findings identify several candidate locations for tumor suppressor genes and oncogenes that are potentially involved in the establishment and progression of papillary thyroid carcinogenesis. © 2001 Wiley‐Liss, Inc.
Retinoid signaling and cardiac anteroposterior segmentation
Authors: Xavier‐Neto José , Rosenthal Nadia , Silva Fábio Alex , Matos Tatiana Guimarães Freitas , Hochgreb Tatiana , Linhares Vania Lucia Ferreira
Published: August 2002

Summary: Establishment of anterior–posterior polarity is one of the earliest decisions in cardiogenesis. Specification of anterior (outflow) and posterior (inflow) structures ensures proper connections between venous system and inflow tract and between arterial tree and outflow tract. The last few years have witnessed remarkable progress in our understanding of cardiac anteroposterior patterning. Molecular cloning and subsequent studies on RALDH2, the key embryonic retinaldehyde dehydrogenase in retinoic acid (RA) synthesis, provided the missing link between teratogenic studies on RA deficiency and excess and normal chamber morphogenesis. We discuss work establishing the foundations of our current understanding of the mechanisms of cardiac anteroposterior segmentation, the reasons why early evidence pointing to the role of RA in anteroposterior segmentation was overlooked, and the key experiments unraveling the role of RA in cardiac anteroposterior segmentation. We have also integrated recent experiments in a model of cardiac anteroposterior patterning in which RALDH2 expression determines anteroposterior boundaries in the heart field. genesis 31:97–104, 2001. © 2001 Wiley‐Liss, Inc.
Increased transgene expression by the mouse tyrosinase enhancer is restricted to neural crest‐derived pigment cells
Authors: Camacho‐Hübner Agnès , Beermann Friedrich
Published: August 2002

Summary: In this study, we have addressed the impact of the mouse tyrosinase enhancer on regulated expression from the mouse tyrosinase promoter during embryonic development. Stable and transient transgenic experiments using the reporter gene lacZ reveal that (1) expression is detected in neural crest‐derived melanoblasts from E11.5 onward, (2) the enhancer does not increase transgenic expression in optic cup‐derived pigment cells of the retinal pigment epithelium (RPE), and (3) expression in the telencephalon is not any longer detected. The importance of the enhancer for expression in pigment cells of the eye was further investigated in adult mice using an attenuated diphtheria toxin A gene. This demonstrated that in presence of the enhancer the transgene expression is specifically targeted to neural crest‐derived melanocytes of the choroid and not, or slightly, to the RPE. This suggests that tyrosinase is differentially regulated in the two pigment cell lineages, and that this promoter can be used to target expression preferentially to the neural crest‐derived melanocyte lineage. genesis 29:180–187, 2001. © 2001 Wiley‐Liss, Inc.
Variegated expression and delayed retinal pigmentation during development in transgenic mice with a deletion in the locus control region of the tyrosinase gene
Authors: Giménez Estela , Giraldo Patricia , Jeffery Glen , Montoliu Lluís
Published: August 2002

Summary: Deletion of the tyrosinase locus control region (LCR) in transgenic mice results in variegated expression in the skin. Here we investigate the pigmentation pattern of other tissues that express tyrosinase: iris, choroid, and retina in the same animals. A mosaic distribution of pigmentation appears in the iris and choroid. Interestingly, a markedly different mosaic pattern is found in the retina, where central areas contain little or no melanin while pigmentation rises to normal levels towards periphery. Further, there is a temporal delay in the initiation and accumulation of pigment in retinal pigmented epithelium (RPE) cells during development, and patterns of adult retinal melanisation in these mice appear arrested at a stage found in early embryogenesis in wild‐type mice. These results demonstrate that the tyrosinase LCR is needed for the correct establishment and maintenance of this expression domain throughout development, but particularly during the later stages of retinal melanisation. genesis 30:21–25, 2001. © 2001 Wiley‐Liss, Inc.
A CamKIIα iCre BAC allows brain‐specific gene inactivation
Authors: Casanova E. , Fehsenfeld S. , Mantamadiotis T. , Lemberger T. , Greiner E. , Stewart A. F. , Schütz G.
Published: August 2002

Summary: We describe the generation of transgenic mouse lines expressing the Cre recombinase enzyme in brain under control of the CamKIIα gene present in a BAC expression vector. The CamKIIα BAC transgene gave a faithful expression pattern resembling the pattern of the endogenous CamKIIα gene. Specifically, high levels of CamKIIα Cre were detected in hippocampus, cortex, and amygdala, and lower levels were detected in striatum, thalamus, and hypothalamus. As expected, no expression was detected in the cerebellum or outside of the brain. The expression level of the BAC CamKIIα driven Cre was shown to be copy number dependent. To test the activity of the Cre recombinase, the transgenic mice were crossed with mice harbouring the CREB (cAMP response element binding protein) allele with the 10th exon flanked by two loxP sites, and recombination was monitored by the disappearance of the CREB protein. Finally, evaluation of the developmental postnatal expression of the CamKIIα Cre BAC revealed the expression of the Cre recombinase as early as P3. genesis 31:37–42, 2001. © 2001 Wiley‐Liss, Inc.
Non‐silicate inclusions in garnet from an ultra‐deep orogenic peridotite
Authors: Van Roermund H. L. M. , Drury M. R. , Barnhoorn A. , De Ronde A.
Published: August 2002

Non‐silicate solid inclusions in garnet from ultra‐deep garnet peridotites, Otrøy, Western Gneiss Region, Norway, have been studied using light‐optical, scanning and analytical electron microscopic techniques. Texturally, the investigated garnets reveal protogranular, porphyroclastic and equigranular microstructures. Protogranular and porphyroclastic garnets contain microstructural evidence of the former existence of ‘super‐titanic’ garnet. The microstructural evidence consists of exsolution textures involving rutile and ilmenite needles //<111>Grt as well as interstitial rutile grains. This exsolution microstructure is similar to the relict majoritic garnet microstructures found in the same peridotite. Some garnets contain both pyroxene and rutile exsolution.

Other non‐silicate mineral inclusions in protogranular and porphyroclastic garnet consist of nickel‐iron alloys (Ni99Fe01) and Cr‐rich spinel. In addition, some protogranular, porphyroclastic and equigranular garnets contain composite Ni‐Fe‐Cu sulphide inclusions. The latter represent immiscible sulphide melt trapped within cracks that have healed.

The original melting temperature of Ni‐Fe‐Cu sulphides was determined as being ≥ 1000°C and contrasts with temperatures derived from garnet–olivine–pyroxene mineral compositions using conventional geothermobarometry (c. 800°C/3 GPa). This contradiction is explained by the decoupling of microstructures and mineral chemistry; the microstructures were formed at higher temperatures than indicated by the current mineral chemistry. The decoupling of microstructures and current mineral chemistry has important applications for geodynamic models. Copyright © 2000 John Wiley & Sons, Ltd.
Expression of functional NK‐1 receptors in murine microglia
Authors: Rasley Amy , Bost Kenneth L. , Olson Julie K. , Miller Stephen D. , Marriott Ian
Published: August 2002

Cells of myeloid origin such as microglia have the potential to contribute significantly to the development of inflammatory responses in the CNS. The ability of the neuropeptide substance P to augment proinflammatory responses by other myeloid cell types such as macrophages and dendritic cells is well recognized. In the present study, we demonstrate the presence of mRNA encoding NK‐1 (substance P) receptors in murine microglia cell lines. Importantly, we have utilized specific antibodies developed by our laboratory to detect the expression of the NK‐1 receptor protein in murine microglia cell lines by Western blot analysis and flow cytometry. Furthermore, we have investigated the presence of this receptor on primary murine microglia and report the presence of authentic NK‐1 receptors as determined by Western blot analysis and flow cytometry. In addition, we demonstrate that NK‐1 receptors expressed on microglia are functional as demonstrated by the ability of nanomolar concentrations of substance P to initiate activation of the transcriptional activator, NF‐κB. Given the weight of evidence supporting the role of substance P–substance P receptor interactions in the initiation of optimal proinflammatory responses by myeloid cells, the demonstration of authentic and functional NK‐1 receptors in microglia identifies this neuropeptide as a potentially important contributor to CNS inflammatory responses during disease states. GLIA 37:258–267, 2002. © 2002 Wiley‐Liss, Inc.
Progesterone and the oligodendroglial lineage: Stage‐dependent biosynthesis and metabolism
Authors: Gago Nathalie , Akwa Yvette , Sananès Nicole , Guennoun Rachida , Baulieu Etienne Emile , El‐Etr Martine , Schumacher Michael
Published: August 2002

Evidence has been accumulated showing that neurosteroids, particularly progesterone (PROG) and its metabolites, may participate in myelination and remyelination in the peripheral nervous system, but very few studies have been undertaken in the central nervous system (CNS). The aim of this work was to investigate the capacities of synthesis and metabolism of PROG at three important stages of the oligodendroglial lineage: oligodendrocyte pre‐progenitors (OPP), oligodendrocyte progenitors (OP), and fully differentiated oligodendrocytes (OL). Experiments have been conducted in vitro using highly purified primary cell cultures from rat brain. Cells were incubated with 3H‐pregnenolone (3H‐PREG), the immediate precursor of PROG, or with 3H‐PROG, and steroids metabolites were then identified by thin layer chromatography and high‐performance liquid chromatography (HPLC). mRNA expression of key steroidogenic enzymes was evaluated by reverse transcription‐polymerase chain reaction (RT‐PCR). The results showed that only OPP and OP, but not OL, expressed 3β‐hydroxysteroid dehydrogenase/Δ5‐Δ4 isomerase mRNA and were able to synthesize PROG from PREG. In the three cell types studied, PROG was metabolized by the type 1 isoform of 5α‐reductase into 5α‐dihydroprogesterone (5α‐DHPROG). This enzyme exhibited a 5‐fold higher activity in OL than in OPP and OP. 5α‐DHPROG was further transformed either into 3α,5α‐tetrahydroprogesterone (3α,5α‐THPROG), known as a positive allosteric modulator of the GABAA receptor, or into the 3β‐isomer. The 3α,5α‐THPROG synthesis was 10 times higher in OPP than in the other cell studied, while the 3β,5α‐THPROG production did not change with cell differentiation. PROG synthesis and metabolism and the dramatic changes in neurosteroidogenesis observed during the oligodendroglial differentiation may contribute to oligodendrocyte development or the myelination process. GLIA 36:295–308, 2001. © 2001 Wiley‐Liss, Inc.
Acetylcholinesterase treatment—modelling potential demand and auditing practice
Authors: Lovestone Simon , Murray David
Published: August 2002

Background

Acetylcholinesterase inhibitors represent an entirely novel treatment option for patients with Alzheimer's disease (AD). As such they represent a significant change in practice and a significant cost pressure on funding bodies.

Objectives

To assess the impact of cholinesterase inhibitors on routine clinical practice.

Methods

We estimated potential demand for the compounds taking into account eligibility criteria and prescribing practice agreed between clinicians and funders. We then audited actual prescribing practice assessing whether the estimated demand matched actual demand and whether practice and prescribing criteria were adhered to.

Results

Over a two‐year period we estimated the demand for treatment at a total of 89 patient years for the population of the audit unit. In practice only 24.5 patient years of therapy were received, the short fall apparently being due to low referral rates for treatment. Prescribing by clinicians matched practice guidelines and a high proportion of three monthly assessments using scales for cognition, function and global state were performed. Using these assessment procedures treatment successes could be differentiated from primary and secondary treatment failures and, where apparently appropriate, treatment could be stopped.

Conclusion

In the real world of clinical practice demand for treatment in AD is modest but likely to grow and assessment with an aim to identifying those receiving benefit from treatment can be achieved. Copyright © 2001 John Wiley & Sons, Ltd.
Implementation and application of a brain template for multiple volumes of interest
Authors: Hammers Alexander , Koepp Matthias J. , Free Samantha L. , Brett Matthew , Richardson Mark P. , Labbé Claire , Cunningham Vincent J. , Brooks David J. , Duncan John
Published: August 2002

We present a region template and a protocol for transforming that template to define anatomical volumes of interest (VOIs) in the human brain without operator intervention, based on software contained in the SPM99 package (Statistical Parametric Mapping, Wellcome Department of Cognitive Neurology, London, UK). We used an MRI of a reference brain to create an anatomical template of 41 VOIs, covering the entire brain, that can be spatially transformed to fit individual brain scans. Modified software allows for the reslicing and adaptation of the tranformed template to any type of coregistered functional data. Individually defined VOIs can be added. We present an assessment of the necessary spatial transformations and compare results obtained for scans acquired in two different orientations. To evaluate the spatial transformations, 11 landmarks distributed throughout the brain were chosen. Euclidean distances between repeat samples at each landmark were averaged across all landmarks to give a mean difference of 1.3 ± 1.0 mm. Average Euclidean distances between landmarks (MRI:transformed template) were 8.1 ± 3.7 mm in anterior‐posterior commissure (ACPC) and 7.6 ± 3.7 mm in temporal lobe (TL) orientation. In this study, we use [11C]‐flumazenil‐(FMZ‐)PET as an example for the application of the region template. Thirty‐four healthy volunteers were scanned, 21 in standard ACPC orientation, 13 in TL orientation. All had high resolution MRI and FMZ‐PET. The average coefficient of variation (CV) of FMZ binding for cortical regions was 0.15, comparable with CVs from manually defined VOIs. FMZ binding was significantly different in 6/19 anatomical areas in the control groups obtained in the different orientations, probably due to anisotropic voxel dimensions. This new template allows for the reliable and fast definition of multiple VOIs. It can be used for different imaging modalities and in different orientations. It is necessary that imaging data for groups compared are acquired in the same orientation. Hum. Brain Mapping 15:165–174, 2002. © 2002 Wiley‐Liss, Inc.
Non‐stationary distributed source approximation: An alternative to improve localization procedures
Authors: Gonzalez Andino S.L. , Grave de Peralta Menendez R. , Lantz C.M. , Blank O. , Michel C. M. , Landis T.
Published: August 2002

Localization of the generators of the scalp measured electrical activity is particularly difficult when a large number of brain regions are simultaneously active. In this study, we describe an approach to automatically isolate scalp potential maps, which are simple enough to expect reasonable results after applying a distributed source localization procedure. The isolation technique is based on the time‐frequency decomposition of the scalp‐measured data by means of a time‐frequency representation. The basic rationale behind the approach is that neural generators synchronize during short time periods over given frequency bands for the codification of information and its transmission. Consequently potential patterns specific for certain time‐frequency pairs should be simpler than those appearing at single times but for all frequencies. The method generalizes the FFT approximation to the case of distributed source models with non‐stationary time behavior. In summary, the non‐stationary distributed source approximation aims to facilitate the localization of distributed source patterns acting at specific time and frequencies for non‐stationary data such as epileptic seizures and single trial event related potentials. The merits of this approach are illustrated here in the analysis of synthetic data as well as in the localization of the epileptogenic area at seizure onset in patients. It is shown that time and frequency at seizure onset can be precisely detected in the time‐frequency domain and those localization results are stable over seizures. The results suggest that the method could also be applied to localize generators in single trial evoked responses or spontaneous activity. Hum. Brain Mapping 14:81–95, 2001. © 2001 Wiley‐Liss, Inc.
The synthesis of six‐membered P‐heterocycles with sterically demanding substituent on the phosphorus atom
Authors: Keglevich György , Forintos Henrietta , Sipos Melinda , Dobó András , Ludányi Krisztina , Vékey Károly , Tungler Antal , Tőke László
Published: August 2002

The ring enlargement of 1‐(2,4,6‐trialkylphenyl)2,5‐dihydro‐1H‐phosphole oxides (1) via 6,6‐dichloro‐3‐Phosphabicyclo[3.1.0]hexanes (2) afforded the double‐bond isomers of 1,2‐dihydrophosphinine oxides (3). Catalytic hydrogenation of the isomeric 1‐(di‐tert‐butyltolyl)‐1,2‐dihydrophosphinine oxides (3a) gave the diastereomers of phosphinane oxide (4), while that of the 1‐(tri‐isopropylphenyl) isomers (5) led predominantly to phospholane oxides (6) formed by ring contraction. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:528–533, 2001
Reactions of phosphite esters and trisdialkylaminophosphines with 5‐substituted 1,3,4‐thiadiazol derivatives
Authors: Arsanious Mona H. N. , Issac Yevette A. , Boulos Leila S.
Published: August 2002

5‐{[(1E)‐(4‐methoxyphenyl)methylene]amino}‐1,3,4‐thiadiazole‐2‐thiol (1a) reacts with trialkyl phosphites (2a–c) to give the respective dialkyl phosphonate adducts (4a–c). On the other hand, the reactions of trisdialkylaminophosphines (3a,b) with 1a, 5‐{[(1E)‐(4‐phenyl)methylene]amino}‐1,3,4‐thiadiazole‐2‐thiol (1b) yield the corresponding open dipolar structures 6a–c. In the case of the reaction of triethyl phosphite (2a) with 1b, both the dialkyl phosphonate adduct (7) and the dipolar product (8a) are obtained. Moreover, triisopropyl phosphite (2c) reacts with 1b to give both the S‐alkyl and the N‐alkyl phosphonate adducts (9a,b), respectively. Mechanisms are proposed to explain the formation of the new products, and their structures were confirmed on the basis of elemental analysis and spectral studies. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:594–601, 2001
Heterocondensed 1,2,3‐diazaphosphorines
Authors: Ivonin Sergey P. , Tolmachev Andrew A. , Chaikovskaya Alexandra A. , Kudraya Tamara N. , Anischenko Andrew A. , Rusanov Eduard B. , Chernega Alexander N. , Pinchuk Alexandr, M.
Published: August 2002

The reaction of phosphorus tribromide with phenylhydrazones of heterocyclic aldehydes leads to formation of a new phosphorus‐containing heterocyclic system—heterocondensed 1,2,3‐diazaphosphorines. Properties of the phosphorus‐containing heterocyclic compounds that have been synthesized are described. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:658–664, 2001
Antimicrobial activity studies of the metal complexes derived from cyclobutane‐substituted thiazole carbamate ligands
Authors: Çukurovalı Alaaddin , Yılmaz İbrahim , Ahmedzade Misir , Kırbağ Sevda
Published: August 2002

Two novel monodentate carbamate ligands derived mainly from 4‐(1‐methyl‐1‐phenylcyclobutyl‐3‐yl)‐2‐aminothiazole and 4‐(1‐phenyl‐1‐methylcyclobutane‐3‐yl)‐2‐(N‐methyl)aminothiazole, have been prepared. The ligands and their metal complexes have been characterized by elemental analyses, IR, 13C, and 1H NMR spectra, as well as UV–Vis, and magnetic susceptibility measurements. Both ligands contain 1 mole of water of crystallization and all complexes are mononuclear. Antimicrobial activities of the ligands and their complexes have been screened against the Bacillus subtitis IMG 22 (bacteria), Micrococcus luteus LA 2971 (bacteria), Escherichia coli DM (bacteria), Staphylococcus aureus COWAN I (bacteria), Saccharamyces cerevisiae UGA 102 (yeast), and Candida albicans CCM 314 (yeast). Thermal properties of the ligands and their complexes have been studied by thermogravimetric analyses (TGA) and differential scanning calorimetry (DSC). © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:665–670, 2001
Building the Foundation for Collaboration: Seamless Learning at a New College
Authors: Crafts Rod , First Zachary , Satwicz Jeffrey
Published: August 2002

The creation of a brand‐new college of engineering was an opportunity to rethink the curriculum and cocurriculum and the interaction between the two.
Targeted health insurance in a low income country and its impact on access and equity in access: Egypt's school health insurance
Authors: Yip Winnie , Berman Peter
Published: August 2002

Governments are constantly faced with competing demands for public funds, thereby necessitating careful use of scarce resources. In Egypt, the School Health Insurance Programme (SHIP) is a government subsidized health insurance system that targets school children. The primary goals of the SHIP include improving access and equity in access to health care for children while, at the same time, ensuring programme sustainability. Using the Egyptian Household Health Utilization and Expenditure Survey (1995), this paper empirically assesses the extent to which the SHIP achieves its stated goals. Our findings show that the SHIP significantly improved access by increasing visit rates and reducing financial burden of use (out‐of‐pocket expenditures). With regard to the success of targeting the poor, conditional upon being covered, the SHIP reduced the differentials in visit rates between the highest and lowest income children. However, only the middle‐income children benefitted from reduced financial burden (within group equity). Moreover, by targeting the children through school enrollment, the SHIP increased the differentials in the average level of access between school‐going children and those not attending school (overall equity). Children not attending school tend to be poor and living in rural areas. Our results also indicate that original calculations may underestimate the SHIP financial outlays, thereby threatening the long run financial sustainability of the programme. Copyright © 2001 John Wiley & Sons, Ltd.