bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discussion on a paper by X. N. Duan and A. M. Chandler
Authors: Nakamura Tsuneyoshi , Nakamura Yutaka 
Published: April 2007

AbstractThe authors have presented the results of inelastic earthquake response analysis of a class of asymmetric building models and concluded that regularly asymmetric buildings excited well into the inelastic range may not be conservatively designed via modal analysis of their elastic models. The purpose of this short communication is to refer to the results in contrast to the authors' and to make some comments on their paper.
Scattering of plane SH waves by a cylindrical alluvial valley of circular‐arc cross‐section
Authors: Yuan Xiaoming , Liao Zheng‐Peng 
Published: April 2007

AbstractA closed‐form solution of two‐dimensional scattering of plane SH waves by a cylindrical alluvial valley of circular‐arc cross‐section in a half‐space is presented using the wave functions expansion. The solution is reduced to solving a set of infinite linear algebraic equations using the exterior region form of Graf's addition theorem. Numerical solutions are obtained by truncation of the infinite equations and their accuracies are demonstrated by convergence of the numerical results to the exact boundary condition with the increasing of the truncation order. The present solution is compared with the existing one presented by Todorovska and Lee for the same problem and their differences are analysed. Complicated effects of the depth‐to‐width ratio of the alluvial valley on surface ground motion are finally illustrated.
A mass penalty technique to control the critical time increment in explicit dynamic finite element analyses
Authors: Macek Richard W. , Aubert Brian H. 
Published: April 2007

AbstractThe applicability of explicit time integration in structural dynamics is often limited by a restrictively small solution time increment. This paper presents a mass penalty technique whereby the highest natural frequencies of a dynamic system can be preferentially lowered with only a minimal effect on the structural modes. Because the critical time increment is inversely proportional to the highest natural frequency, a dramatic increase in the solution time increment may be achieved. An expression is developed for the frequency shift and a number of useful properties of this technique are derived analytically for linear systems. Its utility in non‐linear analyses is demonstrated with several examples.
A probabilistic assessment of seismic damage in ductile structures
Authors: Basu Biswajit , Gupta Vinay K. 
Published: April 2007

AbstractThe current practices in ductility‐based earthquake design ignore the damage caused by the repeated random inelastic excursions. A ductile structure may however suffer different degrees of damage depending on the number and amplitudes of these inelastic excursions. The information about the largest response peak as available from the response spectra may not thus be enough as the higher‐order peaks are likely to play an important role in the progressing damage. A probabilistic model is proposed here to estimate the damage in a structure with a given amount of ductility by using the order statistics of the higher‐order peaks. The proposed formulation relates damage to the entire response process, not just to the largest response. It thus accounts for the different roles played by the total number of peaks in the process, the relative amplitudes and number of excursions, and frequency content of the response process.
When the doorbell rings–a case of building response to a long distance earthquake
Authors: Pan Tso‐Chien 
Published: April 2007

AbstractResponding to ground tremors caused by the magnitude 7–0 Liwa earthquake in Sumatra on 16 February 1994, a doorbell system on the 15th floor of a 17‐storey building in Singapore rang repeatedly at an epicentral distance of more than 750 km. This paper first reviews briefly the regional seismicity, surface geology and effects of local soil amplification for Singapore. It then estimates the building response through the linear and non‐linear analyses of impact conditions for the double‐pendulum doorbell system. Based on the impact analysis results, it is shown that the acceleration response at the 15th floor reached at least 0–02 g and that the base shear coefficient was no less than 1–0 per cent. The response was comparable to the notional horizontal load which usually governs the design of most buildings in Singapore. In view of the fast growing economy and the rapid urbanization of Singapore, it is prudent to re‐evaluate systematically the effects of a long distance, large Sumatra earthquake on Singapore.
Seismic displacements of torsionally unbalanced buildings
Authors: Tso W. K. , Wong C. M. 
Published: April 2007

AbstractA parametric study is carried out to evaluate the seismic displacements at the flexible edge of torsionally unbalanced (TU) structural systems. Guidelines are provided to estimate these displacements so that they can be incorporated in the formulation of the displacement‐based seismic design approach for the design of TU buildings. The ability of three code procedures to estimate the flexible‐edge displacement is examined to show that not all procedures lead to conservative estimates. Finally, it is shown that elastic spectrum analysis incorporating accidental torsion effect is a viable means to estimate the flexible‐edge displacements.
Response of rigid body assemblies to dynamic excitation
Authors: Winkler Tibor , Meguro Kimiro , Yamazaki Fumio 
Published: April 2007

AbstractShaking table tests were conducted to investigate the response of rectangular wooden blocks and block assemblies of various sizes and slenderness to harmonic and earthquake base excitation. The shaking tests were followed by an analytical and a numerical study of response of single blocks and block assemblies. The analytical study was aimed at establishing criteria for the initiation of rocking and of overturning in response to harmonic base motion and consisted of solving numerically the differential equations of motion of a rigid block on a rigid foundation. The numerical study, in the course of which the response of both single blocks and block assemblies was examined, was implemented by means of the Distinct Element Method (DEM). Prior to the DE simulation of actual shaking tests, preliminary analyses were conducted to confirm numerical stability and to evaluate material and damping parameters. Comparing the recorded time histories with those given by the analytical study and the DE simulation, good agreement was found. The distinct element model in use appeared to follow the highly non‐linear motion of rigid body assemblies faithfully to reality. On the basis of the results, provided that the necessary parameters are carefully estimated, the employed DE model can be regarded as an appropriate tool to simulate response of rigid body assemblies to dynamic base excitation.
Hybrid control of seismic‐excited bridge structures
Authors: Yang J. N. , Wu J. C. , Kawashima K. , Unjoh S. 
Published: April 2007

AbstractRecently, several hybrid protective systems have been explored for applications to seismic‐excited bridge structures. In particular, two types of aseismic hybrid protective systems have been shown to be quite effective: (i) rubber bearings and variable dampers (or actuators), and (ii) sliding bearings and actuators. In this paper, control methods are presented for these hybrid protective systems. The control methods are based on the theory of variable structure system (VSS) or sliding mode control (SMC). Emphasis is placed on the static (direct) output feedback controllers using only the information measured from a few sensors without an observer. Simulation results demonstrate that the control methods presented are robust with respect to system parametric uncertainties and the performance is quite remarkable. Sensitivity studies are conducted to evaluate the effectiveness of hybrid protective systems and passive sliding isolators for reducing the response of seismic‐excited bridge structures. The advantages of each protective system are demonstrated by simulation results for a wide range of earthquake intensities.
Statistical analysis of peaks and directivity of earthquake ground motion
Authors: Ansary Mehedi A. , Yamazaki Fumio , Katayama Tsuneo 
Published: April 2007

AbstractConversion factors are useful for attenuation and damage estimation relationships. These factors among different definitions of peaks (i.e. larger, average and resultant) for peak ground motion indices and acceleration response spectrum were investigated. A large number of horizontal acceleration records recorded at 76 free‐field sites of the Japan Meteorological Agency were used in this study. Two orthogonal horizontal components were combined in the time domain to get the maximum resultant peak ground motion indices and acceleration response spectrum in the horizontal plane. From the analysis, the means of the larger/resultant ratio were found to be 0·934 for acceleration, 0·926 for velocity, and 0·913 for displacement. A similar decreasing trend was observed for the means of the average/resultant ratio of the ground motion indices and acceleration response spectrum. The directivity of peak ground motion indices was also examined. It was found that the peak ground motion is more likely to occur in the transverse direction than in other directions. This trend is more prominent in the long‐period contents of ground motion.
Strength enhancement in particulate solids under high loading rates
Authors: Chandra Dipankar , Krauthammer Theodor 
Published: April 2007

AbstractThe so‐called ‘strain‐rate effect’ in any material has been investigated here from a structural dynamics point of view. Starting with lumped‐mass models (SDOF and 2‐DOF) and assuming a rate‐independent failure criterion, it is shown here how a high loading rate produces an effect of strength enhancement in any massive elastic material and how failure takes place in a stronger component of a system as the loading rate increases. Extrapolating the concept of an equivalent elastic modulus as introduced in lumped‐mass models and extending the analysis to a semi‐infinite elastic continuum, an algorithm has been schematized to evaluate an overall equivalent elastic modulus of a concrete body under the influence of high loading rate treating the concrete as a two‐component solid mixture consisting of cement paste matrix and aggregates.
Factors affecting solid phase microextraction (SPME) to concentrate the odorants of Chinese white salted noodles for GC–MS analysis
Authors: Lin Li‐Yun , Peng Chiung‐Huei , Wang Hui‐Er , Wu Tsung‐Han , Chen Cheng‐Chang , Yu Tung‐Hsi , Wu Cheung‐May , Peng Robert Y. 
Published: April 2007

AbstractOver 0.4 billion people consume Chinese white salted noodles (CWSN) as their daily main diet. Rapid flavour and taste control of CWSN has consequently attracted much attention from noodle processors and distributors. In this study, the conventional solid‐phase microextraction (SPME) technique plus GC and GC–MS was used to concentrate the odorants in CWSN and examine its potential for improving the related quality control (QC) technology. The results indicated that the optimum adsorption time and temperature are 160 min and 30 °C, respectively. Higher temperatures are not suggested for SPME because of thermal leakage and desorption possibilities. Moreover, dry adsorption is more stable than wet adsorption regarding the amount adsorbed and the operational stability, and CAR/PDMS was found to be superior to PDMS/DVB in this regard. In this investigation, a total of 25 odorant species were identified; corresponding regains of 55.11 and 31.25 p.p.m. were obtained for dry and wet adsorption, respectively, among which hexanal was the most abundant (37.10 p.p.m. dry adsorption vs. 20.79 p.p.m. wet adsorption), while 2‐heptenal (4.24 p.p.m.), 2‐octenal (2.01 p.p.m.), 2‐pentylfuran (1.91 p.p.m.), 2‐nonenal (1.41 p.p.m.) and 2‐butyl‐2‐octenal (1.35 p.p.m.) were the next in order of decreasing amount. Interestingly, dry adsorption with CAR/PDMS was specifically more efficient for quantification of total aldehydes (52 p.p.m. vs. 28 p.p.m. for wet adsorption). It is concluded that for flavour quality control of CWSN during both processing and storage, such an analytical technology can be very feasible and satisfactory. Copyright © 2007 John Wiley & Sons, Ltd.
Composition and chemical variability of the twig oil of Abies alba Miller from Corsica
Authors: Duquesnoy Emilie , Castola Vincent , Casanova Joseph 
Published: April 2007

AbstractThe composition of the essential oil of twigs of individual trees of Abies alba Miller from Corsica was investigated by CC, GC (RI), GC–MS and 13C‐NMR. Among the 65 identified compounds, limonene, β‐phellandrene, α‐pinene, camphene and β‐pinene were found to be the major components. Fifty‐three oil samples were analysed and the results were submitted to chemometric analysis (K‐means clustering and principal component analysis). Two groups were distinguished within the essential oils. Samples belonging to the first group (64% of the samples) were characterized by a very high content of limonene (mean value 46.1%). Conversely, the mean composition of the samples of the second group (36% of the samples) was dominated by camphene, α‐pinene and limonene. Such a chemical composition is reported for the first time within A. alba essential oils. Copyright © 2007 John Wiley & Sons, Ltd.
External validation of a risk group defined by recursive partitioning analysis in patients with head and neck carcinoma treated with surgery and postoperative radiotherapy
Authors: León Xavier , López Montserrat , Piñeiro Zenaida , Langendijk Johannes A. , Leemans Charles R. , Quer Miquel 
Published: April 2007

AbstractBackground:Several clinical trials have proved that concurrent chemoradiotherapy is more efficacious than radiotherapy alone among high‐risk patients with head and neck squamous cell carcinoma (HNSCC) who undergo surgery. A risk‐group classification defined according to a recursive partitioning analysis (RPA) for these patients has been recently proposed. The objective of the present study was to carry out an external validation of this RPA‐derived classification system.Methods:A retrospective study of 442 HNSCC patients treated with surgery and postoperative radiotherapy was conducted. The external validity of the RPA‐derived classification system was assessed, and its ability to stage patients and to predict locoregional control of the disease was compared with the TNM system.Results:The RPA‐derived classification system succeeded in obtaining a monotonic prognosis gradient in locoregional control of the disease with increasing stage, and achieved greater differences in survival between stages than the TNM and pTNM classifications. Besides, the RPA method had a better homogeneity of the categories included in each stage, and in the heterogeneity between stages.Conclusions:The RPA‐derived classification system allowed for the clear definition of prognostic groups in surgically treated HNSCC patients, improving the prognostic capacity of the TNM and pTNM classifications. The RPA‐derived classification system is a useful tool in the definition of patients who, given a poor prognosis, should be considered candidates to adjuvant chemoradiotherapy. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Phasic cholinergic signaling in the hippocampus: Functional homology with the neocortex?
Authors: Gulledge Allan T. , Kawaguchi Yasuo 
Published: April 2007

AbstractAcetylcholine (ACh) acts as a neurotransmitter in both the hippocampus and neocortex to facilitate learning, memory, and cognitive function. Here we show that transient muscarinic ACh receptor (mAChR) activation inhibits action potential generation in CA1, but not in CA3, pyramidal neurons via activation of an SK‐type calcium‐activated potassium conductance. Hyperpolarizing responses generated by focal ACh application near the somata of CA1 pyramidal neurons were blocked by atropine or the M1‐like mAChR antagonist pirenzepine, but not by the M2‐like mAChR antagonist methoctramine. Inhibitory cholinergic responses required intracellular calcium signaling, as evidenced by their sensitivity to depletion of internal calcium stores or internal calcium chelation. Cholinergic inhibition did not require GABAergic synaptic transmission, but was blocked by apamin, an SK channel antagonist. In contrast to inhibitory effects in CA1 neurons, ACh was primarily depolarizing, and enhanced action potential firing in CA3 pyramidal neurons. These results, when combined with recent data in neocortical neurons, suggest a functional homology in phasic cholinergic signaling in the hippocampus and neocortex whereby ACh preferentially inhibits those neurons in the lower cortical layers (CA1 and layer 5 neurons) that provide the majority of extracortical efferent projections. © 2007 Wiley‐Liss, Inc.
Expression of cyclin D3 through Sp1 sites by histone deacetylase inhibitors is mediated with protein kinase C‐δ (PKC‐δ) signal pathway
Authors: Kim Young‐Ho , Lim Jun Hee , Lee Tae‐Jin , Park Jong‐Wook , Kwon Taeg Kyu 
Published: April 2007

AbstractThe histone deacetylase (HDAC) inhibitors are an exciting new class of drugs that are targeted as anti‐cancer agents. These compounds can induce growth arrest, apoptosis, and/or terminal differentiation in a variety of cancers. The inhibition of HDACs shifts toward hyper‐acetylation, thereby driving transcriptional activation. In present study, HDAC inhibitor apicidin was used to elucidate the effect on expression of cell cycle related proteins and the molecular mechanism for transcriptional regulation of cyclin D3 in response to HDAC inhibitors in human colon cancer cells. We found that apicidin increases the transcriptional activity of cyclin D3 gene, which results in accumulation of cyclin D3 mRNA and protein. Apicidin‐induced cyclin D3 expression is mediated by Sp1 sites within the cyclin D3 promoter. Apicidin‐mediated cyclin D3 expression is attenuated by rottlerin, a specific protein kinase C‐δ (PKC‐δ) inhibitor, but not mitogen‐activated protein kinases (MAPKs) inhibitors. Furthermore, suppression of PKC‐δ expression by transfection with its siRNA prominently attenuated apicidin‐induced cyclin D3 expression. These results indicate that the cyclin D3 induction caused by apicidin was associated with PKC‐δ signaling pathway not MAPKs signaling pathways. Taken together, these results suggest that the activation of cyclin D3 transcription by HDAC inhibitor apicidin was mediated through Sp1 sites and pointed to the possible participation of PKC‐δ. J. Cell. Biochem. 101: 987–995, 2007. © 2007 Wiley‐Liss, Inc.
Age‐dependent telomere‐shortening is repressed by phosphorylated α‐tocopherol together with cellular longevity and intracellular oxidative‐stress reduction in human brain microvascular endotheliocytes
Authors: Tanaka Yasufumi , Moritoh Yusuke , Miwa Nobuhiko 
Published: April 2007

AbstractCellular life‐span of neonatal human brain microvascular endotheliocytes (HBME) was estimated by population doubling levels (PDLs) for serial subcultivations until spontaneous proliferation stoppage, and was 2.4‐fold longer for continuous administration with the 6‐O‐phosphorylated derivative (TocP) of α‐tocopherol (Toc), being bio‐available owing to its water‐solubility, or TocP plus 2‐O‐phosphorylated ascorbate (Asc2P), and 1.3‐fold longer with Asc2P, at a dose of 150 µM, than for the non‐administered control. Enlarged cell diameters indicative of cellular aging were repressed for TocP‐administered cells as analyzed with a channelizer. Age‐dependent shortening of telomeric DNA length (291 bp/PDL) was slowed markedly for TocP (165 bp/PDL) or TocP plus Asc2P, but slightly for Asc2P. Telomerase activity as assessed by the PCR‐based TRAP method was detectable slightly at younger ages but no longer at middle ages for the non‐administered cells, but, for TocP‐administered cells, was intensely detected at younger ages and appreciably until middle ages. Intracellular TocP amounts were not changed age‐dependently in contrast to a marked decrease in Toc which accrued from TocP esterolysis. This may be partly attributed to age‐dependent changes in the lipid peroxidation product acrolein (ACR), which was abundant at older ages in non‐administered cells, but scarcely in TocP‐administered cells. Furthermore, intracellular reactive oxygen species (ROS) such as H2O2 and hydroperoxides as detected using the redox indicator CDCFH‐DA was less abundant in TocP‐administered cells than in non‐administered cells. Thus the telomeric‐DNA retention, concurrently with retained telomerase activity, was shown to be correlated with cellular longevity, and may be supported by diminished oxidative stress, in hydrophobic microenvironment, which can be achieved by TocP rather than AscP. J. Cell. Biochem. 102: 689–703, 2007. © 2007 Wiley‐Liss, Inc.
Evaluation of relative DNA binding affinities of anthrapyrazoles by electrospray ionization mass spectrometry
Authors: Smith Suncerae I. , Guziec Lynn J. , Guziec Frank S. , Hasinoff Brian B. , Brodbelt Jennifer S. 
Published: April 2007

AbstractBinding interactions of a new series of anthrapyrazoles (APs) with DNA were evaluated by electrospray ionization mass spectrometry (ESI‐MS). Relative binding affinities were estimated from the ESI‐MS data based on the fraction of bound DNA for DNA/anthrapyrazole mixtures, and they show a correlation to the shift in melting point of the DNA measured from a previous study. Minimal sequence specificity was observed for the series of anthrapyrazoles. Upon collisionally activated dissociation of the duplex/anthrapyrazole complexes, typically ejection of the ligand was the dominant pathway for most of the complexes. However, for complexes containing AP2 or mitoxantrone, strand separation with the ligand remaining on one of the single strands was observed, indicative of a different binding mode or stronger binding. Copyright © 2007 John Wiley & Sons, Ltd.
Protein content and gluten quality of durum wheat (Triticum turgidum subsp. durum) as affected by sowing date
Authors: Motzo Rosella , Fois Simonetta , Giunta Francesco 
Published: April 2007

AbstractThe end use quality of durum wheat is sensitive to the environmental conditions pertaining before and during grain filling, and can therefore be modified by manipulation of cultivar and sowing date. A field trial was carried out to study the effect on protein content and gluten quality of varying both sowing date (October, December and March) and cultivar (Simeto, Colosseo and Creso). A delay in sowing date was associated with a decrease in mean grain weight, but not in grain nitrogen content, thus leading to an overall increase from 10.7 to 14.7% in grain protein percentage. Independent of sowing date, over 78% of the grain nitrogen was derived from re‐translocation from vegetative tissue. The similar amounts of nitrogen accumulated in each grain at maturity were set by the similarity in the amount of nitrogen available at anthesis. The observed increase in protein percentage partly explained the greater dough strength (alveographic W) observed in material harvested from the latest sowing. The gluten index, on the other hand, decreased as sowing was delayed. Given the parallel increase in glutenin percentage, we propose that temperatures above 30 °C at the end of the grain filling period have a negative effect on the gluten polymerisation process. Copyright © 2007 Society of Chemical Industry