bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seismic tests on a 16‐storey cast‐in‐place r/c building, and stochastic simulation results
Authors: Zaicenco A. , Alkaz V. 
Published: September 2002

AbstractRecords of the dynamic response of a 16‐storey cast‐in‐place reinforced concrete apartment building subjected to moderate‐magnitude (Mw < 7·0) earthquakes were performed before and after three recent significant Vrancea earthquakes. They are compared with random vibration simulation results based on a newly developed computer program and with an FEM linear model of the building, employing time‐history analysis. Theoretical investigations fitted to the results of the tests confirmed the validity of the approaches used and demonstrate satisfactorily good compatibility of the simulated and observed structural responses. The seismic records from the test building (str. Roz 15, Kishinev, Moldova), consisting of displacements and accelerations, were taken in ‘free‐field’, and at the foundation, the 8th storey and the top of the building. Copyright © 2001 John Wiley & Sons, Ltd.
X‐ray fluorescence analysis at the naval research laboratory
Authors: Gilfrich John V. 
Published: September 2002

AbstractIn the 50 years that the Naval Research Laboratory has been involved in x‐ray fluorescence analysis, there have been many developments which have made the technique what it is today. Many of the advances owe at least part of their success to the contributions made by the scientists of a specific group. This essay will present one man's opinion of the significant work by members of that group, as related to the impact that x‐ray fluorescence analysis has had on the field of analytical chemistry in general. Published in 2001 by John Wiley & Sons, Ltd.
Soft x‐ray multilayer monochromator with improved resolution and low specular background
Authors: André Jean‐Michel , Benbalagh Rabah , Barchewitz Robert , Ravet Marie‐Françoise , Raynal Alain , Delmotte Frank , Bridou Françoise , Julie Gwaénäelle , Bosseboeuf Alain , Laval René , Soullié Gérard , Rémond Christian , Fialin Michel 
Published: September 2002

AbstractA new soft‐x‐ray multilayer monochromator with an improved resolution and a low specular background is presented. The principles of the device, based on the use of a lamellar multilayer amplitude grating (LMAG), are summarized. The techniques of fabrication of the monochromator (multilayer deposition, UV lithography and reactive ion etching) are given. The performance of this new monochromator at photon energies around 1500 eV is demonstrated. Copyright © 2001 John Wiley & Sons, Ltd.
Metallic thin film thickness determination using electron probe microanalysis
Authors: Campos C. S. , Coleoni E. A. , Trincavelli J. C. , Kaschny J. , Hubbler R. , Soares M. R. F. , Vasconcellos M. A. Z. 
Published: September 2002

AbstractAn experimental procedure to determine metallic thin film thicknesses by using electron probe microanalysis (EPMA) is presented. Several monoelemental films of Al, Ti, Cr, Cu, Nb, Mo and Au with different thicknesses, deposited on an Si substrate, were characterized by Rutherford backscattering spectrometry for thickness measurement. Characteristic x‐ray intensities were measured for films, substrate and bulk standards. The ratios of these intensities (k‐ratio), were compared with those obtained from Monte Carlo simulations based on the subroutine package PENELOPE, and good agreement was found. The results from simulation and experiments were added to build calibration curves of k‐ratio vs thickness for the monoelemental films investigated. A simple analytical function was fitted to these curves and the behavior of its parameters with atomic number was studied. Copyright © 2001 John Wiley & Sons, Ltd.
New procedure for intensity and detection limit determination in spectral trace analysis: application for trace mercury by TXRF
Authors: Bennun L. , Greaves E. D. , Blostein J. J. 
Published: September 2002

AbstractA new procedure for the identification and quantification of spectral signals based on the method of maximum likelihood is presented. It is particularly appropriate for the analysis of signal interference or cases of a small signal in a sizeable noisy background. The formulation yields precise signal intensity values and has advantages in its estimation of detection limits over established signal processing methods. The method developed is applicable to spectroscopic techniques where net counts are proportional to acquisition time, such as particle induced x‐ray emission (PIXE) and other x‐ray fluorescence spectroscopic methods, Mössbauer spectroscopy, some cases of α, β and γ spectroscopy, etc. The proposed method was applied in two experimental instances to the quantification of traces of the XRF mercury signal in the presence of a large, strongly interfering gold signal: (i) In liquid solutions assayed by means of total reflection x‐ray fluorescence (TXRF) spectrometry, where mercury amalgamated on a gold‐plated thin film sputtered on pure quartz reflectors was irradiated with a molybdenum anode x‐ray tube; detection limits achieved by the method were 100 ppb, significantly lower than obtained by standard net‐area processing procedures; (ii) solid sample XRF spectra analyzed with the proposed method yielded consistent and reliable signal intensities and evidence of detection limits almost an order of magnitude smaller than achieved by standard net‐area processing procedures. Copyright © 2002 John Wiley & Sons, Ltd.
Arsenic detection in nineteenth century Portuguese King post mortem tissues by energy‐dispersive x‐ray fluorescence spectrometry
Authors: Carvalho M. L. , Rodrigues Ferreira F. E. , Neves M. C. M. , Casaca C. , Cunha A. S. , Marques J. P. , Amorim P. , Marques A. F. , Marques M. I. 
Published: September 2002

AbstractArsenic and other heavy metal concentrations in post mortem soft tissues from a Portuguese King of the nineteenth century were studied by energy‐dispersive x‐ray fluorescence analysis. This work is an attempt to clarify the strange death of the King, through the analysis of his post mortem soft tissue remains, which were kept inside a Chinese porcelain container since his death in 1826. The container was put in a wooden coffin and buried underground in a chapel of the St Vicente de Fora Monastery in Lisbon. Quantitative elemental analysis of the remains showed very high concentrations of arsenic and lead, which on average correspond to a few hundred times the mean normal values for contemporary human soft tissues. Increased levels of Cu were found, and also small enrichments for Fe and Zn, probably due to either enrichment during the 175 years or contamination by direct intake from the container, or both. The results obtained are consistent with acute arsenic poisoning, reinforcing the conclusions from the medical anatomical–pathological report, based on the analysis of the fragments by scanning electron microscopy. Copyright © 2002 John Wiley & Sons, Ltd.
Correlation between element concentrations and x‐ray diffraction patterns in hair
Authors: Trounova V. A. , Vazina A. A. , Lanina N. F. , Sergienko P. M. , Kondratyev V. I. 
Published: September 2002

AbstractA correlation between the character of x‐ray patterns and the element composition of human hair was found. X‐ray diffraction and fluorescence analysis of human hair were carried out using synchrotron radiation of the storage ring of the Institute of Nuclear Physics, SB RAS. Some factors leading to the appearance of the diffuse ring in keratin fibrils, which corresponds to a molar periodicity of 4.44 nm, were shown, as was the ring's connection with the element composition of hair. The role of metals in the matrix complex was considered. Copyright © 2002 John Wiley & Sons, Ltd.
Two mechanisms for oxidation of cytosolic NADPH by Kluyveromyces lactis mitochondria
Authors: Overkamp Karin M. , Bakker Barbara M. , Steensma H. Y. , van Dijken Johannes P. , Pronk Jack T. 
Published: September 2002

AbstractNull mutations in the structural gene encoding phosphoglucose isomerase completely abolish activity of this glycolytic enzyme in Kluyveromyces lactis and Saccharomyces cerevisiae. In S. cerevisiae, the pgi1 null mutation abolishes growth on glucose, whereas K.lactis rag2 null mutants still grow on glucose. It has been proposed that, in the latter case, growth on glucose is made possible by an ability of K. lactis mitochondria to oxidize cytosolic NADPH. This would allow for a re‐routing of glucose dissimilation via the pentose‐phosphate pathway. Consistent with this hypothesis, mitochondria of S. cerevisiae cannot oxidize NADPH. In the present study, the ability of K. lactis mitochondria tooxidize cytosolic NADPH was experimentally investigated. Respiration‐competent mitochondria were isolated from aerobic, glucose‐limited chemostat cultures of the wild‐type K. lactis strain CBS 2359 and from an isogenic rag2Δ strain. Oxygen‐uptake experiments confirmed the presence of a mitochondrial NADPH dehydrogenase in K.lactis. This activity was ca. 2.5‐fold higher in the rag2Δ mutant than in the wild‐type strain. In contrast to mitochondria from wild‐type K. lactis, mitochondria from the rag2Δ mutant exhibited high rates of ethanol‐dependent oxygen uptake. Subcellular fractionation studies demonstrated that, in the rag2Δ mutant, a mitochondrial alcohol dehydrogenase was present and that activity of a cytosolic NADPH‐dependent ‘acetaldehyde reductase’ was also increased. These observations indicate that two mechanisms may participate inmitochondrial oxidation of cytosolic NADPH by K. lactis mitochondria: (a) direct oxidation of cytosolic NADPH by a mitochondrial NADPH dehydrogenase; and (b) a two‐compartment transhydrogenase cycle involving NADP+‐ and NAD+‐dependent alcohol dehydrogenases. Copyright © 2002 John Wiley & Sons, Ltd.
A microarray‐assisted screen for potential Hap1 and Rox1 target genes in Saccharomyces cerevisiae
Authors: Ter Linde José J. M. , Steensma H. Yde 
Published: September 2002

AbstractSaccharomyces cerevisiae adapts to altered oxygen availability by differentially expressing a number of genes. Under aerobic conditions oxygen control of gene expression is exerted through the activator Hap1 and the repressor Rox1. The Hap1 transcription factor senses cellular heme status and increases expression of aerobic genes in response to oxygen. The repression of hypoxic genes under normoxic conditions results from Hap1‐mediated activation of ROX1 transcription. To allow the identification of additional Hap1 and Rox1 target genes, genome‐wide expression was analysed in aerobically, chemostat‐cultivated hap1 and rox1 null mutants. The microarray results show that deletion of HAP1 causes a lower transcript level of 51 genes. Transcription of 40 genes was increased in rox1 mutant cells compared to wild‐type cells. Combining these results with our previously described transcriptome data of aerobically and anaerobically grown cells and with computational analysis of the promoters identified 24 genes that are potentially regulated by Hap1, and 38 genes satisfied the criteria of being direct targets of Rox1. In addition, this work provides further evidence that Rox1 controls transcription of anaerobic genes through repression under normoxic conditions. Copyright © 2002 John Wiley & Sons, Ltd.
Molecular characterization of Saccharomyces cerevisiae Sco2p reveals a high degree of redundancy with Sco1p
Authors: Lode Anja , Paret Claudia , Rödel Gerhard 
Published: September 2002

AbstractThe Saccharomyces cerevisiae gene SCO1 has been shown to play an essential role in the transfer of copper to the CuA‐centre of the mitochondrial cytochrome c oxidase subunit Cox2p. By contrast, the function of Sco2p, the gene product of the highly homologous SCO2 gene, remains to be elucidated. Deletion of the SCO2 gene does not affect growth on a variety of carbon sources, including glycerol, lactate and ethanol. We report here, that Sco2p is anchored in the mitochondrial membrane by a single transmembrane segment and displays a similar tripartite structure as Sco1p. Most parts of Sco1p can be replaced by the homologous parts of Sco2p without loss of function. A short stretch of 13 amino acids, immediately adjacent to the transmembrane region, is crucial for Sco1p function and cannot be replaced by its Sco2p counterpart. We propose that this region is relevant for the correct spatial orientation of the C‐terminal part of the protein. Immunoprecipitation and in vitro binding assays show that Sco2p interacts with the C‐terminal portion of Cox2p. This interaction is neither dependent on bound copper ions nor on the presence of Sco1p. Furthermore we report on in vitro binding assays which show that Sco2p can form homomeric complexes, but also heteromeric complexes with Sco1p. Our data suggest that Sco2p is involved in the transfer of copper to Cox2p, but that this activity is insufficient for oxidative growth and not able to substitute for Sco1p activity. Copyright © 2002 John Wiley & Sons, Ltd.
6‐phosphofructokinase from Pichia pastoris: purification, kinetic and molecular characterization of the enzyme
Authors: Kirchberger Jürgen , Bär Jörg , Schellenberger Wolfgang , Dihazi Hassan , Kopperschläger Gerhard 
Published: September 2002

Abstract6‐Phosphofructokinase from Pichia pastoris was purified for the first time to homogeneity applying seven steps, including pseudo‐affinity dye‐ligand chromatography on Procion Blue H‐5R‐Sepharose. The specific activity of the purified enzyme was about 80 U/mg. It behaves as a typically allosteric 6‐phosphofructokinase exhibiting activation by AMP and fructose 2,6‐bis(phosphate), inhibition by ATP and cooperativity to fructose 6‐phosphate. However, in comparison with the enzymes from Saccharomyces cerevisiae and Kluyveromyces lactis, the activation ratio of 6‐phosphofructokinase from Pichia pastoris by AMP is several times higher, the ATP inhibition is stronger and the apparent affinity to fructose 6‐phosphate is significantly lower. Aqueous two‐phase affinity partitioning with Cibacron Blue F3G‐A did not reflect remarkable structural differences of the nucleotide binding sites of the Pfks from Pichia pastoris and Saccharomyces cerevisiae. The structural organisation of the active enzyme seems to be different in comparison with hetero‐octameric 6‐phosphofructokinases from other yeast species. The enzyme was found to be a hetero‐oligomer with an molecular mass of 975 kDa (sedimentation equilibrium measurements) consisting of two distinct types of subunits in an equimolar ratio with molecular masses of 113 kDa and 98 kDa (SDS–PAGE), respectively, and a third non‐covalently complexed protein component (34 kDa, SDS–PAGE). The latter seems to be necessary for the catalytic activity of the enzyme. Sequencing of the N‐terminus (VTKDSIXRDLEXENXGXXFF) and of peptide fragments by applying MALDI–TOF PSD, m/z 1517.3 (DAMNVVNH) and m/z 2177.2 [AQNCNVC(L/I)SVHEAHTM] gave no relevant information about the identity of this protein. Copyright © 2002 John Wiley & Sons, Ltd.
Rapid differentiation of Candida albicans from other Candida species using its unique germ tube formation at 39° C
Authors: Kim Donghwa , Shin Woon‐Seob , Lee Kyoung‐Ho , Kim Kyunghoon , Young Park Joo , Koh Choon‐Myung 
Published: September 2002

AbstractIn this study, we found that no Candida species other than C. albicans is able to form germ tubes at 39° C in serum‐free YEPD (1% (w/v) yeast extract, 2% (w/v) peptone and 2% (w/v) dextrose) media, which makes it easy to identify C. albicans from other Candida species. When cultivated in rabbit serum for at least 2 h at 37° C, more than 60% of C. albicans cells generated germ tubes. In YEPD, however, germ tubes began to appear from C. albicans cells within 30 min at 39° C, and more than 60% of C. albicans cells formed the germ tubes after 1 h at 39° C. Standard Candida strains (ATCC, CBS), three C. albicans and two C. dubliniensis strains were cultured in serum at 37° C for 2 h and in YEPD at 39° C for 1 h. All of the three C. albicans formed germ tubes at 39° C. The two C. dubliniensis strains formed germ tubes in serum at 37° C, but grew as a yeast form in YEPD at 39° C. All of the clinically isolated C. albicans strains in our laboratory formed germ tubes in YEPD at 39° C for 1 h, and none of the clinically isolated Candida species other than C. albicans generated germ tubes in YEPD at 39° C. Thus, the unique germ tube formation of C. albicans induced by high temperature (39° C) in YEPD could be applied to a protocol for the rapid and convenient identification of C. albicans in clinical laboratories. Copyright © 2002 John Wiley & Sons, Ltd.
Is the embryo culture system useful for collecting primordial germ cells from endangered avian embryos?
Authors: Kawashima Takaharu , Sakai Rika , Kano Koichiro , Tamaki Yoshinori , Hashimoto Koichiro 
Published: September 2002

AbstractThe development of artificial means to conserve endangered avian species appears to be urgently needed. Procedures developed in recent years for experimental embryology with primordial germ cells (PGCs) may help prevent the extinction of endangered species. To this end, we examined the embryo culture system (ECS) for collection of PGCs using chick embryos as a model system. Our results showed that the ECS had no detrimental effect on the number of PGCs that could be collected from the bloodstream at the optimal developmental stages. Also, our findings indicated that the number of PGCs recoverable from the blood depended on the developmental stage. We conclude that the ECS, which allows direct observation of embryos during development, is very useful for collecting PGCs and for obtaining basic developmental information that can be extended to invaluable endangered avian embryos. Various aspects of the ECS are discussed. Zoo Biol 21:287–294, 2002. © 2002 Wiley‐Liss, Inc.
Signals from the X: signal transduction and X‐linked mental retardation
Authors: Barnes Anthony P. , Milgram Sharon L. 
Published: September 2002

AbstractThe dramatic increase in genomic information is allowing the rapid identification of genes that are altered in mental retardation (MR). It is necessary to place their resulting gene products in their cellular context to understand how they may have contributed to a patient's cognitive deficits. This review will consider signaling molecules that have been implicated in X‐linked MR and the known pathways by which these proteins covey information will be delineated. The proteins discussed include four distinct classes: transmembrane receptors, guanine nucleotide related proteins, kinases, and translational regulators.
Mental Retardation Research Center at Boston Children's Hospital/Harvard Medical School
Authors: Volpe Joseph J. 
Published: September 2002

AbstractThe MRRC at Children's Hospital/Harvard Medical School is focused on research in genetics and neuroscience. Both clinical and basic science approaches are abundant. Major interdisciplinary programs, particularly in the areas of neonatal brain injury, human cerebral cortical malformations, and human neuromuscular disorders, interdigitate basic and clinical research in cohesive research programs. The core research support facilities serve as the nidus for this large research effort, encompassing 65 externally funded clinical and basic scientists.
Life of a flapping liquid sheet
Authors: VILLERMAUX E. , CLANET C. 
Published: September 2002

A round liquid jet with density ρ, surface tension σ and diameter D0 impacting a solid
circular surface at normal incidence with velocity U0 takes the form of a radially
expanding sheet whose thickness decreases with distance from the impact point. When
the sheet develops in a still environment with density ρa = αρ, it destabilizes, provided
the impacting Weber number We = ρU20D0/σ is larger than about 40α−1/2, as a result
of a shear instability with the surrounding medium, in a sinuous, flag-like motion.
We show how the instability properties set both the radial extent of the liquid sheet
and the drop formation process at its rim. The shear instability gives the liquid a
flag-like motion, ultimately triggering a Rayleigh–Taylor instability at the rim of the
sheet which disintegrates, at the radial location R, into disjointed droplets of size d
such thatR/D0 ∼ α−2/3We−1/3
and
d/D0 ∼ α−2/3We−1.The features of the sheet instability, its radius and the droplet sizes are determined
experimentally for a broad range of control parameters, using different liquids and
ambient-medium densities.
Prediction of precipitation associated with a western disturbance using a high‐resolution regional model: role of parameterisation of physical processes
Authors: Azadi M , Mohanty U C , Madan O P , Padmanabhamurty B 
Published: September 2002

AbstractIn this study a non‐hydrostatic version of the PSU/NCAR mesoscale model is used to simulate an active western disturbance (WD) that affected the Indian region in January 1997. The role of the planetary boundary layer (PBL) and convection parameterisation schemes in the development of the WD is investigated. Analysis and predictions for some fields, including sea level pressure, geopotential height, temperature, horizontal wind and precipitation are examined. Some statistical scores are also calculated and compared. It is found that the performance of the Hong‐Pan (as implemented in the NCAR MRF model) and Betts‐Miller (or Grell) schemes as PBL and convection parameterisation schemes respectively are best compared to the other schemes used in this study. Copyright © 2002 Royal Meteorological Society.
An operational method for forecasting total column ozone for Punta Arenas, Chile
Authors: McMahon R Monreal , Aguilar R , Valderrama V , Burt P J A 
Published: September 2002

AbstractOwing to the decrease of stratospheric ozone during the southern spring (starting in September), the city of Punta Arenas (53.1°S, 70.9°W) and its surroundings are exposed to a high incidence of ultra‐violet‐B (UV‐B) radiation during this period. Ozone denatures DNA, and prolonged exposure may cause skin carcinoma and cataracts. Consequently, there is great concern among the inhabitants of this region regarding the possible effects of long‐term exposure to UV‐B. In this work we apply and further develop a pilot study carried out in 1995 which looks at the simple operational method of forecasting ozone levels some 42 hours in advance. The method is based on the prediction of the 100 mb‐temperature from ECMWF (European Centre for Medium‐Range Weather Forecasts), which is well correlated with total column ozone levels. It allows the inhabitants of the Magallanes region to be alerted to potentially high incidences of UV‐B radiation during the Austral spring. Copyright © 2002 Royal Meteorological Society.
Sensitivity of monsoon circulation and precipitation over India to model horizontal resolution and orographic effects
Authors: Wu Yihua , Raman S , Mohanty U C , Madala R V 
Published: September 2002

AbstractA triple‐nested regional weather prediction model was used to investigate the effects of the model horizontal resolution and orography on southwest monsoon precipitation over India. Numerical experiments with different resolution topography and different horizontal resolution model domains were conducted. Simulation results indicate that both the distribution and intensity of simulated southwest monsoon precipitation over India is highly sensitive to model horizontal resolution and topography. The model with a finer resolution is able to predict mesoscale organization of rainfall over the land mass. Rainfall predicted over the coarse domain is much less than that observed owing to its unrealistic representation of orographic effects and mesoscale forcings. Simulated wind speed, surface pressure, and latent and sensible heat flux distributions are also sensitive to the model resolution. Larger values and more detailed structure of the distribution of the wind speed and latent and sensible heat fluxes are simulated in the finer domains. Copyright © 2002 Royal Meteorological Society.