bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical p‐version refinement studies for the regularized stress‐BEM
Authors: Richardson J. D.
Published: November 2003

In the development of the boundary element method (BEM) and the finite element method (FEM) researchers have typically selected similar basis functions. That is, both methods typically employ low‐order interpolations such as piece‐wise linear or piece‐wise quadratic and rely on h‐version refinement to increase accuracy as required. In the case of the FEM, the decision to use low‐order elements is made for computational efficiency as an attractive compromise between local modeling accuracy and sparseness of the resulting linear system. However, in many BEM formulations, low‐order elements may be the only practical choice given the complexity of using analytic integration formulae in conjunction with special integral interpretations. Unlike their efficient use in the FEM, fine meshes of low‐order elements in the BEM are highly inefficient from a computational standpoint given the dense nature of BEM systems. Moreover, owing to singularities in the kernel functions, the BEM should be expected to benefit more so than the FEM from very high levels of local accuracy. Through the use of regularized algorithms which only require numerical integration, p‐version refinement in the BEM is easily extended to include any set of basis functions with no significant increase in programming complexity. Numerical results show that by using interpolations as high as 12th and 16th order, one can expect reductions in error by as many as five orders of magnitude over comparable algorithms based on similar system size. For two‐dimensional problems, it is also shown that, for a given level of error, one can expect reductions in system size by an order of magnitude, thus leading to a reduction in computational expense for conventional algorithms by three orders of magnitude. Copyright © 2003 John Wiley & Sons, Ltd.
A new scheme for efficient and direct shape optimization of complex structures represented by polygonal meshes
Authors: Shen Jie , Yoon David
Published: November 2003

In this paper, a new shape optimization approach is proposed to provide an efficient optimization solution of complex structures represented by polygonal meshes. Our approach consists of three main steps: (1) surface partitioning of polygonal meshes; (2) generation of shape design variables on the basis of partitioned surface patches; and (3) gradient‐based shape optimization of the structures by reducing a weighted compliance among all load cases. The main contributions of this paper include (i) that our approach can be directly applied on polygonal meshes with the reduction of design variables or decision variables by 10 to 1000 times, compared to the conventional design variable scheme of using each mesh node; (ii) our perturbation scheme is mathematically proven with respect to maintaining the smoothness of each surface patch, except on its boundary; and (iii) overall, our approach can be used to automate time‐consuming shape optimization of polygonal meshes to a greater extent. Numerical experiments have been conducted and the results indicate the effectiveness of the approach. Copyright © 2003 John Wiley & Sons, Ltd.
Lithium intercalation on amorphous V2O5 thin film, obtained by r.f. deposition, using in situ sample transfer for XPS analysis
Authors: Salvi Anna Maria , Guascito Maria Rachele , DeBonis Angela , Simone Francesca , Pennisi Agostino , Decker Franco
Published: November 2003

Spectroscopic and electrochemical properties of amorphous V2O5 films, prepared by r.f. sputter deposition, were compared before and after electrochemical lithium intercalation. The films gave a cyclic voltammogram typical of vanadium pentoxide with two/three steps of reversible electrochromism (yellow–green–blue). The expected effect of lithiation on chemical state and surface composition was monitored using XPS. A careful curve‐fitting procedure of the detailed spectra was adopted and the in‐depth profile analysis of the intercalated films clearly showed their surface reorganization as a function of time and ultrahigh vacuum conditions. The first objective of this work was to establish the influence of lithium intercalation while minimising degradation effects due to its high reactivity with the atmosphere, taking advantage of the in situ sample transfer facility. Copyright © 2003 John Wiley & Sons, Ltd.
Degradation of poly(vinyl chloride) and nitrocellulose in XPS
Authors: Seah M. P. , Spencer S. J.
Published: November 2003

Measurements have been made of the degradation rates for poly(vinyl chloride) (PVC) and nitrocellulose with cellulose acetate (NC) in x‐ray photoelectron spectroscopy. These materials form part of earlier studies published by others to evaluate instrumental degradation factors. In the earlier studies, results showed significant scatter such that the relative rates varied significantly from instrument to instrument. It is shown here that this variation could arise from different levels of adventitious electrons in the different instruments as well as different layer thicknesses exhibiting the degradation in PVC and NC. The former depends on electrodes in the system and the neutralizing parameters, whereas the latter causes the relative degradation rates to depend on the angle of emission of the detected electrons. These will have varied from laboratory to laboratory in the earlier study. The present study leads to simple recommendations for operating conditions to reduce the degradation effects observed. Copyright © 2003 John Wiley & Sons, Ltd.
Effects of riboflavin photoproducts on microbial activity during photosensitization of atrazine transformation
Authors: Glover Hollis , Hwang Huey‐Min , Zeng Kui
Published: November 2003

The contributions and effects of photolysis and microbial assemblages to 37.6 mg/L riboflavin‐sensitized atrazine transformation were studied along with the toxicity of the intermediate mixtures. High‐performance liquid chromatography analysis revealed that riboflavin significantly enhanced the phototransformation of atrazine (10 mg/L) by reducing the parent compound concentration to less than 20% in 72 h. However, radiotracer measurements indicated atrazine was not mineralized to the same degree after 3 days of exposure. We hypothesize that riboflavin‐sensitized transformation of atrazine is primarily photochemical; however, the biological component seems to promote overall atrazine degradation under solar irradiation. Based on the results of spread plate counting or 14C‐glucose mineralization measurement, at a test concentration of 12.1 mg/L, lumichrome (a major riboflavin photoproduct) was found to be nontoxic to the test microbial assemblages in a reservoir water sample. Other riboflavin photoproducts and/or certain chemically reactive species were speculated to cause a cytotoxic effect. Overall, our data indicate that riboflavin may be an economical photosensitizing agent for atrazine degradation, but the apparent photoinduced cytotoxicity observed during transformation is of concern to the microbial assemblages that are needed for complete remediation. Further investigation into why the biotic component enhances riboflavin phototransformation of atrazine and the time frame of microbial recovery from riboflavin inhibition is needed. Such work may lead to cost‐effective surface water treatment systems involving combined photochemical and microbial degradation processes. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 361–367, 2003.
Cavitation‐induced pyrolysis of toxic chlorophenol by high‐frequency ultrasonic irradiation
Authors: Hao Hongwei , Wu Minsheng , Chen Yifang , Yin Yingwu , Lü Zhaolin
Published: November 2003

p‐Chlorophenol (4‐CP) is a recalcitrant organic pollutant that is biologically toxic in industrial wastewater. A high‐frequency ultrasonic device operated at 1.7 MHz was designed and used successfully to degrade 4‐CP. Iodine liberation in the KI aqueous solution confirmed that effective cavitation occurred under the high‐frequency ultrasonic irradiation. No products or intermediate products were detected following the sonochemical degradation by 1H–nuclear magnetic resonance spectrum and mass spectrum after ultrasonic irradiation. It was concluded that the dominant degradation mechanism was high‐temperature pyrolysis to inorganic products in ultrasonic cavities rather than free‐radical oxidation. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 413–417, 2003.
Toxicity of chlorpyrifos to the early life history stages of eastern rainbowfish Melanotaenia splendida splendida (Peters 1866) in tropical Australia
Authors: Humphrey Craig , Klumpp David W.
Published: November 2003

Various life history stages of the eastern rainbowfish Melanotaenia splendida splendida were exposed to the organophosphorus insecticide chlorpyrifos at different temperatures and under different exposure regimes. Chlorpyrifos was found to be highly toxic to all stages of M. s. splendida and became significantly more toxic to embryonic and larval fish as the temperature of the exposure increased. The toxicity of chlorpyrifos was found to be different for each of the various life history stages tested, with the LC50 values increasing from 0.02 mg chlorpyrifos L−1, for eggs and sperm exposed prior to fertilization, to 2.02 mg chlorpyrifos L−1, for eggs exposed after fertilization and hardening of the chorion. Sublethal early life stage (ELS) tests revealed that larval length and otolith perimeter were the most sensitive indicators of stress, with significant differences from the controls at chlorpyrifos concentrations as low as 0.006 mg L−1. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 418–427, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.
Upregulation of cyp2e1 and cyp3a activities in histamine‐deficient histidine decarboxylase gene targeted mice
Authors: Tamási Viola , Fülöp A. Kristóf , Hegyi Krisztina , Monostory Katalin , Falus András
Published: November 2003

Histamine is a biogenic amine with multiple physiological functions. Its importance in allergic inflammation is well characterized; moreover, it plays a role in the regulation of gastric acid production, various hypothalamic functions, such as food uptake, and enhancing TH2 balance during immune responses. Using histidine decarboxylase gene targeted (HDC−/−) BALB/c mice, we studied the effect of the absence of histamine on four cytochrome P450 enzyme activities. Their selective substrates were measured: ethoxyresorufin O‐dealkylase activity of CYP1A, pentoxyresorufin O‐dealkylase activity of CYP2B, chlorzoxazone 6‐hydroxylase activity of CYP2E1 and ethylmorphine N‐demethylase activity of CYP3A.

The results indicate a significant elevation of CYP2E1 and CYP3A activities, however, no change in CYP1A and CYP2B activities was seen in HDC targeted mice compared to wild type controls with identical genetic backgrounds.
Conformational fluctuations in anthrax protective antigen: a possible role of calcium in the folding pathway of the protein
Authors: Gupta Pradeep K , Chandra Harish , Gaur Reetika , Kurupati Raj K , Chowdhury Shantanu , Tandon Vibha , Singh Yogendra , Maithal Kapil
Published: November 2003

Protective antigen (PA) is the central receptor binding component of anthrax toxin, which translocates catalytic components of the toxin into the cytosol of mammalian cells. Ever since the crystal structure of PA was solved, there have been speculations regarding the possible role of calcium ions present in domain I of the protein. We have carried out a systematic study to elucidate the effect of calcium removal on the structural stability of PA using various optical spectroscopic techniques, limited proteolysis and mutational analysis. Urea denaturation studies clearly suggest that the unfolding pathway of the protein follows a non‐two state transition with apo‐PA being an intermediate species, whereas the folding pathway shows that calcium ions may be critical for the initial protein assembly.
Transcriptional regulation of the human GM3 synthase (hST3Gal V) gene during monocytic differentiation of HL‐60 cells
Authors: Choi Hee-Jung , Chung Tae-Wook , Kang Nam-Young , Kim Kyoung-Sook , Lee Young-Choon , Kim Cheorl-Ho
Published: November 2003

We studied the transcriptional regulation of human GM3 synthase (hST3Gal V) during monocytic differentiation of HL‐60 cells induced by 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA). Northern blot and reverse transcription polymerase chain reaction indicated that the induction of hST3Gal V by TPA is regulated at the transcriptional level. To elucidate the mechanism underlying the regulation of hST3Gal V gene expression during the differentiation of HL‐60 cells induced by TPA, we characterized the promoter region of the hST3Gal V gene. Functional analysis of the 5′‐flanking region of the hST3Gal V gene by the transient expression method showed that the −177 to −83 region, which contains a cAMP responsive element binding protein (CREB) binding site at −143, functions as the TPA‐inducible promoter in HL‐60 cells. In addition, gel shift assays and site‐directed mutagenesis indicated that the CREB binding site at −143 is crucial for the TPA‐induced expression of the hST3Gal V in HL‐60 cells.
Inhibition by dexamethasone of interleukin 13 production via glucocorticoid receptor‐mediated inhibition of c‐Jun phosphorylation
Authors: Hirasawa Noriyasu , Izumi Shinichiroh , Linwong Watchara , Ohuchi Kazuo
Published: November 2003

The antigen stimulation of RBL‐2H3 cells induced interleukin 13 (IL‐13) production, which was inhibited by the steroidal anti‐inflammatory drug dexamethasone and by the c‐Jun N‐terminal kinase (JNK) inhibitor SP600125. Dexamethasone did not inhibit the antigen‐induced phosphorylation of JNK but inhibited that of c‐Jun. In a cell‐free system, the phosphorylation of glutathione S‐transferase‐fused c‐Jun by recombinant JNK was not inhibited by dexamethasone but was inhibited by the addition of recombinant glucocorticoid receptor (GR). These findings suggest that the inhibition of antigen‐induced IL‐13 production by dexamethasone is due to the GR‐mediated inhibition of c‐Jun phosphorylation induced by JNK.
Streptomycin and its analogues are potent inhibitors of the hypotonicity‐induced Ca2+ entry and Cl− channel activity
Authors: Shen Meng-Ru , Chou Cheng-Yang , Chiu Wen-Tai
Published: November 2003

Streptomycin is a common antibiotic used in culture media. It is also a known blocker of stretch‐activated and mechanosensitive ion channels in neurons and cardiac myocytes. But very little information is available on its effect in the regulation of epithelial ion channels. Osmotic swelling is a kind of mechanical stretch. The opening of stretch‐activated Ca2+ channels contributes to hypotonicity‐induced Ca2+ influx which is necessary for the activation of volume‐regulated Cl− channels in human cervical cancer cells. This study aimed to investigate the role of streptomycin in cell volume regulation. Treatment of cervical cancer SiHa cells with streptomycin and its analogues (gentamicin and netilmicin) did not affect the basal cytosolic Ca2+ ([Ca2+]i) level. But it attenuated the hypotonicity‐stimulated increase of [Ca2+]i in a dose‐dependent manner with half‐maximal inhibitory concentrations (IC50) of 25, 90 and 200 μM for streptomycin, gentamicin and netilmicin, respectively, when measured at room temperature. In contrast, under free extracellular Ca2+ condition, hypotonic stress only induced a small, progressive increase of [Ca2+]i, while 500 μM streptomycin did not affect this Ca2+ signaling. Streptomycin and its analogues (gentamicin and netilmicin) also inhibited the activation of volume‐regulated Cl− channels in a dose‐dependent manner with IC50 of 30, 95 and 250 μM at room temperature, respectively. Chronic culture with 50 μM streptomycin downregulates the activity of volume‐regulated Cl− channels and retards the process of regulatory volume decrease in SiHa cells and MDCK cells. We suggest that using cells chronically cultured with streptomycin to study epithelial ion channels risks studying cellular and molecular pathology rather than physiology.
A novel β(1,6)‐N‐acetylglucosaminyltransferase V (GnT‐VB)1
Authors: Kaneko Mika , Alvarez-Manilla Gerardo , Kamar Maria , Lee Intaek , Lee Jin-Kyu , Troupe Karolyn , Zhang Wei-jie , Osawa Motoki , Pierce Michael
Published: November 2003

UDP‐N‐acetylglucosamine:α(1,6)‐D‐mannoside β(1,6)‐N‐acetylglucosaminyltransferase (GnT‐V, Mgat5) functions in the biosynthesis of N‐linked glycans and is transcriptionally upregulated by oncogene signaling. We report here the cloning and characterization of a human cDNA encoding a distinct enzyme with related substrate specificity, termed GnT‐VB, which is predicted to have 53% similarity to the original amino acid sequence of GnT‐V(A). Transient expression of GnT‐VB cDNA in COS7 cells yielded significant increases of activity toward GnT‐VA acceptors, including synthetic saccharides and N‐linked glycopeptides, with some differences in specificity. Unlike GnT‐VA, GnT‐VB required divalent cation for full activity. EST databases showed expression of a 6 bp (+) splice isoform of GnT‐VB; when expressed, this enzyme showed significantly reduced activity. CHO Lec4 cells, which do not express GnT‐VA or B activity, lack synthesis of the N‐linked β(1,6) branch, and do not bind L‐phytohemagglutinin (L‐PHA), were transfected with GnT‐VB or GnT‐VA; both then bound significant amounts of L‐PHA, demonstrating that both enzymes synthesized N‐linked β(1,6) branched glycans in vivo. Real‐time polymerase chain reaction results showed that GnT‐VB mRNA was highly expressed in brain and testis, with lesser levels in other tissues, while human GnT‐VA showed a more general expression, but with low levels in brain and no expression in skeletal muscle.
Human homologue of ariadne promotes the ubiquitylation of translation initiation factor 4E homologous protein, 4EHP
Authors: Tan Nancy G.S. , Ardley Helen C. , Scott Gina B. , Rose Stephen A. , Markham Alexander F. , Robinson Philip A.
Published: November 2003

Human homologue of Drosophila ariadne (HHARI) is a RING‐IBR‐RING domain protein identified through its ability to bind the human ubiquitin‐conjugating enzyme, UbcH7. We now demonstrate that HHARI also interacts with the eukaryotic mRNA cap binding protein, translation initiation factor 4E homologous protein (4EHP), via the N‐terminal RING1 finger of HHARI. HHARI, 4EHP and UbcH7 do not form a stable heterotrimeric complex as 4EHP cannot immunoprecipitate UbcH7 even in the presence of HHARI. Overexpression of 4EHP and HHARI in mammalian cells leads to polyubiquitylation of 4EHP. By contrast, HHARI does not promote its own autoubiquitylation. Thus, by promoting the ubiquitin‐mediated degradation of 4EHP, HHARI may have a role in both protein degradation and protein translation.
Bcl‐2 antisense oligodeoxynucleotide increases the sensitivity of leukemic cells to arsenic trioxide
Authors: Zhang Y. , Shen W.L.
Published: November 2003

Cell culture, tissue chemistry and flow cytometry were used to determine whether antisense bcl‐2 oligodeoxynucleotides enhanced the sensitivity of leukemia cells to arsenic trioxide. A combination of arsenic trioxide with antisense bcl‐2 oligodeoxynucleotides inhibited cell growth, induced apoptosis and induced bcl‐2 protein expression in K562 and NB4 leukemic cells more significantly than either arsenic trioxide or the oligodeoxynucleotides on their own (P<0.01). Thus, bcl‐2 antisense oligodeoxynucleotides increase the sensitivity of leukemic cells to arsenic trioxide. Combined use of the two agents could be a novel and attractive strategy in leukemia treatment.
Sind Selbstmanagement-Trainings effektiv?
Authors: Klein Stephan , König Cornelius J. , Kleinmann Martin
Published: November 2003

Zusammenfassung. Diese Studie vergleicht die Effektivität zweier Selbstmanagement-Trainingsansätze. Der eine lehnt sich an Beschreibungen von in der Wirtschaft üblichen Selbstmanagement-Trainings an (n = 53), der andere an einen in der Klinischen Psychologie verbreiteten Selbstregulations-Ansatz (n = 53). Letzterer sollte effektiver sein, weil die Aufmerksamkeit auf kleinen, individualisierten Verbesserungsschritten liegt und nicht auf großen Lebenszielen wie bei Ersterem. Als abhängige Variablen wurden Selbstmanagement-Fertigkeiten, die Selbstwirksamkeit und die Lebenszufriedenheit vor und nach dem Training und auch nach drei Monaten gemessen. Weitere Variablen (z.B. eine Beurteilung des Trainings) wurden nach dem Training und/oder nach drei Monaten gemessen. Die Ergebnisse zeigten, dass nur das Training, das in Anlehnung an den Selbstregulations-Ansatz konstruiert wurde, effektiv war. Dies spricht für die Anwendbarkeit adaptierter klinisch-psychologischer Erkenntnisse zu Verhaltensmodifikationen auch in der Personalpsychologie und gegen ein ungeprüftes Übernehmen von Trainings ohne Evaluierung.
Diurnal centroid of ecosystem energy and carbon fluxes at FLUXNET sites
Authors: Wilson Kell B. , Baldocchi Dennis , Falge Eva , Aubinet Marc , Berbigier Paul , Bernhofer Christian , Dolman Han , Field Chris , Goldstein Allen , Granier Andre , Hollinger Dave , Katul Gabriel , Law B. E. , Meyers Tilden , Moncrieff John , Monson Russ , Tenhunen John , Valentini Riccardo , Verma Shashi , Wofsy Steve
Published: November 2003

Data from a network of eddy covariance stations in Europe and North America (FLUXNET) were analyzed to examine the diurnal patterns of surface energy and carbon fluxes during the summer period across a range of ecosystems and climates. Diurnal trends were quantified by assessing the time of day surface fluxes and meteorological variable reached peak values, using the “diurnal centroid” method; the diurnal centroid enabled us to discern whether the peak activity of the variable of interest is weighted more toward the morning or afternoon. In this paper, diurnal centroid estimates were used to diagnose which atmospheric and physiological processes controlled carbon dioxide, water vapor, and sensible heat fluxes across different ecosystems and climates. Sensitivity tests suggested that the diurnal centroids for latent (LE) and sensible (H) heat flux depend on atmospheric resistance, static stability in the free atmosphere, stomatal response to vapor pressure deficit, and advection. With respect to diurnal trends of surface energy fluxes at FLUXNET sites, maximum LE occurred later in the day relative to H at most tall forests with continental climates. The lag between LE and H was reduced or reversed at sites that were influenced by advection or by afternoon stomatal closure. The time of peak carbon uptake of temperate forests occurred earlier relative to the temporal peak of photosynthetically active radiation, as compared to boreal forests. The timing of this peak occurred earlier during periods with low soil water content, as it did during the summer in Mediterranean climates. In this case, the diurnal centroid for the CO2 flux was influenced by the response of respiration and photosynthesis to increasing afternoon temperature and by afternoon stomatal closure.
Seismic structure of the Mid‐Atlantic Ridge, 8–9°S
Authors: Minshull T. A. , Bruguier N. J. , Brozena J. M.
Published: November 2003

The Mid‐Atlantic Ridge at 8–9°S is characterized by a transition from axial valley to axial high and recent episodes of ridge jumping and ridge propagation. We present constraints on the structure of 0–4 Ma crust in this region on the basis of the analysis of wide‐angle seismic data from a grid of profiles across and parallel to the current and abandoned spreading centers. A 350–800 m thick oceanic layer 2A, interpreted as high‐porosity extrusive basalts, is underlain by a ∼2.0–2.5 km layer 2B with velocities which increase with age and decrease in the vicinity of the pseudofaults. Layer 3 velocities are uniform across the area except for a possible localized anomaly at the ridge axis. The crustal thickness varies from 6–7 km near the pseudofaults formed by ridge propagation to 9–10 km at the segment center of the recently (∼0.3 Ma) abandoned spreading center. Seismically determined crustal thickness and density variations and age‐related lithospheric cooling can plausibly account for all observed variations in gravity across the area, and there is no requirement for the thicker crust at the segment center to be underlain by hot mantle. The transition from axial valley to axial high occurs at a crustal thickness of ∼8 km.
Intercomparison between satellite‐derived aerosol optical thickness and PM2.5 mass: Implications for air quality studies
Authors: Wang Jun , Christopher Sundar A.
Published: November 2003

We explore the relationship between column aerosol optical thickness (AOT) derived from the Moderate Resolution Imaging SpectroRadiometer (MODIS) on the Terra/Aqua satellites and hourly fine particulate mass (PM2.5) measured at the surface at seven locations in Jefferson county, Alabama for 2002. Results indicate that there is a good correlation between the satellite‐derived AOT and PM2.5 (linear correlation coefficient, R = 0.7) indicating that most of the aerosols are in the well‐mixed lower boundary layer during the satellite overpass times. There is excellent agreement between the monthly mean PM2.5 and MODIS AOT (R > 0.9), with maximum values during the summer months due to enhanced photolysis. The PM2.5 has a distinct diurnal signature with maxima in the early morning (6:00 ∼ 8:00AM) due to increased traffic flow and restricted mixing depths during these hours. Using simple empirical linear relationships derived between the MODIS AOT and 24hr mean PM2.5 we show that the MODIS AOT can be used quantitatively to estimate air quality categories as defined by the U.S. Environmental Protection Agency (EPA) with an accuracy of more than 90% in cloud‐free conditions. We discuss the factors that affect the correlation between satellite‐derived AOT and PM2.5 mass, and emphasize that more research is needed before applying these methods and results over other areas.
Multiple scattering of high‐frequency seismic waves in the deep Earth: PKP precursor analysis and inversion for mantle granularity
Authors: Margerin L. , Nolet G.
Published: November 2003

We apply the theory of radiative transfer to invert for the small‐scale structure of the mantle, by fitting mean amplitude envelopes of precursors to PKP in the time domain. The data set previously used by have been augmented with new deep events from the 1997–2000 period, thereby doubling the number of high‐quality records selected for this study. Regional and global average amplitudes are measured in six bins covering the 124–142° epicentral distance range. The inversion focuses on stacks for strongly scattering wave paths only and aims to determine the depth extent and power spectrum of the mantle heterogeneities that cause the scattered signals. We find that the restriction of scatterers to the D″ layer is incompatible with observations. Instead, whole mantle scattering models reproduce with reasonable accuracy the time dependence of precursors, in agreement with previous findings. Exponential correlations predict a spatial rate of decay of the precursor amplitude which is much faster than observed. Thus we are led to propose a new model of mantle heterogeneity, richer in small‐scale than exponential media, that fits uniformly the data. An analytic form of the correlation function and power spectrum of our new model is given explicitly. It is shown that the precise length scale of heterogeneities is fundamentally unresolvable because of the limited range of observations. The perturbations in P wave velocities required to fit the data are only of order 0.1–0.2%, which is more than 1 order of magnitude less than found in previous studies.
Tidal front around the Hainan Island, northwest of the South China Sea
Authors: Hu Jianyu Y. , Kawamura Hiroshi , Tang Danling L.
Published: November 2003

As the coastal fronts being detected by the SeaWiFS‐derived Chl‐a concentrations and AVHRR‐derived SST images, a three‐dimensional primitive equation numerical model is used to study the physical mechanisms for the formation of fronts around the Hainan Island, northwest of the South China Sea. Several monthly averaged SeaWiFS‐derived Chl‐a concentrations indicate that higher Chl‐a zones usually exist along the coasts of the Zhanjiang Peninsula, the Beibu Gulf (or the Gulf of Tonkin) and the Hainan Island. Obvious surface Chl‐a fronts can thus be seen narrowly adjacent to the higher Chl‐a zones. AVHRR‐derived SST images indicate several other fronts that have a large seasonal variation. The SST fronts are formed in the Beibu Gulf and in the northeastern area off the Hainan Island in winter. The numerical modeling of seven major tidal constituents (M2, S2, K1, O1, P1, N2, and K2) indicates that two high kinetic energy zones appear in the Qiongzhou Strait and near the southwestern coast of the Hainan Island. The value of log (h/u3), where h is depth in meter and u is the depth‐mean tidal current in m/s, is calculated to predict the frontal position. It is indicated that the locations of contour lines log (h/u3) = 2.9 ∼ 3.0 are in good agreement with the frontal positions detected by the satellite observations. Therefore these Chl‐a fronts can be considered to be mainly induced by the tidal mixing while the monsoon wind, solar radiation, and coastal dynamics may play an important role for the seasonal variation of several other fronts.
Quantifying the relative contributions of riparian and hillslope zones to catchment runoff
Authors: McGlynn Brian L. , McDonnell Jeffrey J.
Published: November 2003

The spatial and temporal sources of headwater catchment runoff are poorly understood. We quantified the contributions of hillslopes and riparian zones to streamflow for two storm events in a highly responsive, steep, wet watershed located on the west coast of the South Island of New Zealand. We examined the spatial and temporal components of catchment storm flow using a simple continuity‐based approach. We tested this with independent isotopic/solute mass balance hydrograph separation techniques. We monitored catchment runoff, internal hydrological response, isotopic, and solute dynamics at a trenched hillslope, and at hillslope and riparian positions in a 2.6‐ha catchment. The gauged hillslope was used to isolate and quantify (by difference) riparian and hillslope zone contributions to the 2.6‐ha headwater catchment. Utilizing flow‐based approaches and a tracer‐based mass balance mixing model, we found that hillslope runoff comprised 2–16% of total catchment storm runoff during a small 27‐mm event and 47–55% during a larger 70‐mm event. However, less than 4% of the new water collected at the catchment outlet originated from the hillslopes during each event. We found that in the 27‐mm rain event, 84–97% of total storm runoff was generated in the riparian zone. In a larger 70‐mm event, riparian water dominated total flow early in the event, although the hillslope became the main contributor once hillslope runoff was initiated. Despite the large amount of subsurface hillslope runoff in total storm runoff during the second larger event, riparian and channel zones accounted for 96% of the new water measured at the catchment outlet. Riparian water dominated between events, throughout small runoff events, and during early portions of large events. While this sequencing of catchment position contributions to flow has been conceptualized for some time, this is the first study to quantify this timing, constrained by hydrometric, isotopic, and solute approaches.
Upward trends in the use of community mental health and social work services in the Netherlands between 1979 and 1995: are particular sociodemographic groups responsible?
Authors: Ten Have M. , Te Grotenhuis M. , Meertens V. , Scheepers P. , Beekman A. T. F. , Vollebergh W.
Published: November 2003

Objective:  We investigate 1) trends in use of community mental health care (CMHC) and community social work (CSW) by Dutch households in 1979–1995; 2) whether such trends can be explained by long‐term relative changes in service use or in sizes of particular household categories.

Method:  Data was derived from the Facilities Use Surveys, cross‐sectional population studies recording Dutch household characteristics and service use since 1979. A simulation technique was used to explain trends in service use.

Results:  Use of CMHC and CSW virtually doubled in recent decades. Such trends are not explained by increasing relative service utilization in particular household categories, and only marginally by shifts in the relative sizes of such categories. They are attributable to growing rates of utilization throughout society.

Conclusion:  Trends in service use are explained by broad changes in help‐seeking behaviour. Policymakers should act on these findings to narrow the persisting inequalities in service uptake.
Indications for and outcome of antidepressant medication in a general population: a prescription database and medical record study, in Jämtland county, Sweden, 1995
Authors: Henriksson S. , Boëthius G. , Håkansson J. , Isacsson G.
Published: November 2003

Objective:  To examine the indications for prescribing antidepressants and the clinical outcome when they are prescribed for the treatment of depression, and compare tricyclic antidepressants (TCAs) and selective serotonin re‐uptake inhibitors (SSRIs) in these respects.

Method:  A naturalistic study of a prospective prescription monitoring database and medical records.

Results:  Depression was the indication for 23% of the tricyclic treatments and for 82% of the SSRI treatments. A successful treatment of the depression was found in 20% of the TCA cases and 41% of the SSRI cases (NS).

Conclusion:  This study provides evidence that the main use of SSRIs in 1995 is the treatment of depression. The study implies that SSRIs have a more favourable outcome in ‘real life’ than TCAs.
Clinical and sociodemographic predictors of response to augmentation, or dose increase among depressed outpatients resistant to fluoxetine 20 mg/day
Authors: Perlis R. H. , Alpert J. , Nierenberg A. A. , Mischoulon D. , Yeung A. , Rosenbaum J. F. , Fava M.
Published: November 2003

Objective: Patients with major depressive disorder often show only partial or no response to antidepressants, necessitating next‐step interventions such as dose increase or augmentation. Factors moderating response to these next‐step interventions are not well‐studied.

Method: In this randomized, double‐blind investigation of next‐step treatments in 101 outpatients who failed to respond to fluoxetine 20 mg for 8 weeks, the impact of depressive course and sociodemographic factors on likelihood of treatment response following dose increase or lithium or desipramine augmentation was examined.

Results: After controlling for depression severity at baseline, current marriage and earlier onset of depression were associated with greater likelihood of response in a logistic regression. Intervention strategy was not predictive of response.

Conclusion: Marital status and earlier onset of depression may be clinically useful in predicting outcome following any next‐step intervention for treatment resistance, rather than with particular strategies.
Association of meteorological factors with suicide
Authors: Deisenhammer E. A. , Kemmler G. , Parson P.
Published: November 2003

Objective:  To identify weather factors associated with an increased risk of suicide. In a number of prior studies an influence of meteorological conditions on the incidence of suicide or attempted suicide has been suggested.

Method:  Official data on the suicide cases of the state of Tyrol, Austria, assessed over a period of 6 years (n = 702) were correlated with a number of meteorological factors assessed at eight weather stations.

Results:  The risk of committing suicide was significantly higher on days with high temperatures, low relative humidity or a thunderstorm and on days following a thunderstorm. The multiple logistic regression analysis left ‘temperature’ and ‘thunderstorm on the preceding day’ as significant factors, even after adjustment for sociodemographic and geographical variables.

Conclusion:  Within the interaction of psychological and environmental influences in the development of suicidal ideation and behaviour, specific meteorological conditions may additionally contribute to the risk of suicide in predisposed individuals.
Nominal Wage Rigidity in Contract Data: A Parametric Approach
Authors: Christofides Louis N. , Tuen Leung Man
Published: November 2003

Using wage agreements reached in the Canadian unionized sector during 1976–99, a period of high as well as exceptionally low inflation, we consider how histograms of wage adjustment changed as inflation reached the low levels of the 1990s. The histograms and parametric tests suggest that wage adjustment is characterized by downward nominal rigidity and significant spikes at zero. There is some evidence of modest menu‐cost effects. We examine whether the rigidity features of wage adjustment are sensitive to indexation provisions, and investigate whether the distinction between short and long contracts is useful.
Intertemporal Substitution of Effort: Some Empirical Evidence
Authors: Treble John G.
Published: November 2003

The labour economics literature refers often to effort, but there is little empirical evidence as to how productivity and effort respond to wage rate variations. An unusual natural experiment in which wage rates suffered an exogenous change of two weeks' duration gives some insight into the magnitude of this effect. For a group of workers in Victorian County Durham, the effort response, measured as the impact of a temporary wage rate change on output per shift, dominates the response of attendance. Comparison of the estimates presented here with those in Treble (Journal of Economic History, 61, 414–38, 2001) suggests that the effects are short lived.
18O composition of CO2 and H2O ecosystem pools and fluxes in a tallgrass prairie: Simulations and comparisons to measurements
Authors: Riley William J. , Still Christopher J. , Helliker Brent R. , Ribas‐Carbo Miguel , Berry Joseph A.
Published: November 2003

In this paper we describe measurements and modeling of 18O in CO2 and H2O pools and fluxes at a tallgrass prairie site in Oklahoma. We present measurements of the δ18O value of leaf water, depth‐resolved soil water, atmospheric water vapor, and Keeling plot δ18O intercepts for net soil‐surface CO2 and ecosystem CO2 and H2O fluxes during three periods of the 2000 growing season. Daytime discrimination against C18OO, as calculated from measured above‐canopy CO2 and δ18O gradients, is also presented. To interpret the isotope measurements, we applied an integrated land‐surface and isotope model (ISOLSM) that simulates ecosystem H218O and C18OO stocks and fluxes. ISOLSM accurately predicted the measured isotopic composition of ecosystem water pools and the δ18O value of net ecosystem CO2 and H2O fluxes. Simulations indicate that incomplete equilibration between CO2 and H2O within C4 plant leaves can have a substantial impact on ecosystem discrimination. Diurnal variations in the δ18O value of above‐canopy vapor had a small impact on the predicted δ18O value of ecosystem water pools, although sustained differences had a large impact. Diurnal variations in the δ18O value of above‐canopy CO2 substantially affected the predicted ecosystem discrimination. Leaves dominate the ecosystem 18O‐isoflux in CO2 during the growing season, while the soil contribution is relatively small and less variable. However, interpreting daytime measurements of ecosystem C18OO fluxes requires accurate predictions of both soil and leaf 18O‐isofluxes.
Climate change and extension of the Ginkgo biloba L. growing season in Japan
Authors: Matsumoto Kazuho , Ohta Takeshi , Irasawa Michiya , Nakamura Tsutomu
Published: November 2003

To understand the effects of climate change on the growing season of plants in Japan, we conducted trend analysis of phenological phases and examined the relationship between phenology and air temperatures. We used phenological data for Ginkgo biloba L., collected from 1953 to 2000. We defined the beginning and the end of the growing season (BGS and EGS) as the dates of budding and leaf fall, respectively. Changes in the air temperature in the 45 days before the date of BGS affected annual variation in BGS. The annual variation in air temperature over the 85 days before EGS affected the date of EGS. The average annual air temperature in Japan has increased by 1.3°C over the last four decades (1961–2000), and this increase has caused changes in ginkgo phenology. In the last five decades (1953–2000), BGS has occurred approximately 4 days earlier than previously, and EGS has occurred about 8 days later. Consequently, since 1953 the length of the growing season (LGS) has been extended by 12 days. Since around 1970, LGS and air temperatures have shown increasing trends. Although many researchers have stated that phenological events are not affected by the air temperature in the fall, we found high correlations not only between budding dates and air temperatures in spring but also between leaf‐fall dates and air temperatures in autumn. If the mean annual air temperature increases by 1°C, LGS could be extended by 10 days. We also examined the spatial distribution of the rate of LGS extension, but we did not find an obvious relationship between LGS extension and latitude.
Potential for detecting changes in soil organic carbon concentrations resulting from climate change
Authors: Conen Franz , Yakutin Mikhail V. , Sambuu Anna D.
Published: November 2003

The interaction between soil organic carbon pools and climate change is an important determinant of future atmospheric CO2 concentrations. Much effort has so far been allocated to manipulative process studies and predictive modelling exercises. Here, we examine the potential for directly detecting predicted changes through repeated soil sampling. Two contrasting benchmark plots were selected in the steppe at the Russian–Mongolian border, where soil organic carbon losses are predicted to be around 10% over the first 50 years of climate change. In both plots, 50 samples were taken to 20 and 30 cm depths. The estimated time intervals before re‐sampling by the same method that were likely to prove significant soil organic carbon losses (α=0.05; statistical power=0.90) were 43 and 26 years.
Influence of total intravenous and inhalational anaesthesia on haemostasis during tympanoplasty
Authors: Özer E. , Çeli̇ker V. , Aypar Ü. , Başgül E.
Published: November 2003

Background:  Surgical trauma leads to systemic changes in haemostasis. Haematological changes activated by surgery may become so prominent that changes caused by anaesthesia might be hidden or underestimated. Therefore, we have undertaken a prospective study to compare the behaviour of selected factors involved in the coagulation and fibrinolytic systems.

Methods:  Forty healthy adult patients scheduled for otological surgery were enrolled in the study. Upon receiving informed consent, they were randomly assigned to receive either inhalational (IA) or total intravenous anaesthesia (TIVA). Platelet function (PFA100TM), disseminated intravascular coagulopathy (DIC) panel, and generalized d‐dimer (GFC) were studied during certain periods of anaesthesia to identify the changes in haemostasis.

Results:  Statistically, no significant change in DIC parameters were encountered between the two groups. No statistical difference was found between the two groups in the measured coagulation parameters, but statistically GFC showed slight activation in the 1st hour of surgical intervention.

Conclusion:  Presuming a minimal traumatic effect of surgical procedure on the determined variables, we conclude that different anaesthetic techniques have a negligible effect on platelet activation and fibrinolysis. The clinical relevance of coagulation activation and fibrinolysis during different anaesthetic techniques remains to be investigated.
Cognitive dysfunction after minor surgery in the elderly
Authors: Canet J. , Raeder J. , Rasmussen L. S. , Enlund M. , Kuipers H. M. , Hanning C. D. , Jolles J. , Korttila K. , Siersma V. D. , Dodds C. , Abildstrom H. , Sneyd J. R. , Vila P. , Johnson T. , Muñoz Corsini L. , Silverstein J. H. , Nielsen I. K. , Moller J. T. ,   for the ispocd2 investigators
Published: November 2003

Background:  Major surgery is frequently associated with postoperative cognitive dysfunction (POCD) in elderly patients. Type of surgery and hospitalization may be important prognostic factors. The aims of the study were to find the incidence and risk factors for POCD in elderly patients undergoing minor surgery.

Methods:  We enrolled 372 patients aged greater than 60 years scheduled for minor surgery under general anesthesia. According to local practice, patients were allocated to either in‐ (199) or out‐patient (173) care. Cognitive function was assessed using neuropsychological testing preoperatively and 7 days and 3 months postoperatively. Postoperative cognitive dysfunction was defined using Z‐score analysis.

Results:  At 7 days, the incidence (confidence interval) of POCD in patients undergoing minor surgery was 6.8% (4.3–10.1). At 3 months the incidence of POCD was 6.6% (4.1–10.0). Logistic regression analysis identified the following significant risk factors: age greater than 70 years (odds ratio [OR]: 3.8 [1.7–8.7], P = 0.01) and in‐ vs. out‐patient surgery (OR: 2.8 [1.2–6.3], P = 0.04).

Conclusions:  Our finding of less cognitive dysfunction in the first postoperative week in elderly patients undergoing minor surgery on an out‐patient basis supports a strategy of avoiding hospitalization of older patients when possible.
Post‐operative hypoalbuminaemia and procalcitonin elevation for prediction of outcome in cardiopulmonary bypass surgery
Authors: Fritz H. G. , Brandes H. , Bredle D. L. , Bitterlich A. , Vollandt R. , Specht M. , Franke U. F. W. , Wahlers T. , Meier‐Hellmann A.
Published: November 2003

Background:  Because few studies have addressed postoperative hypoalbuminaemia in relation to hospital mortality, we evaluated this association and the prognostic value of increased procalcitonin (PCT) after cardiopulmonary bypass (CPB) surgery.

Methods:  In 454 consecutive patients undergoing CPB, minimal serum albumin, colloid osmotic pressure (COP) and maximal PCT were retrospectively obtained from the 2nd to 10th postoperative day. Receiver operating characteristic (ROC) and multiple regression analyses determined independent predictive strength for 28‐day mortality from preoperative albumin, Euroscore, postoperative minimal albumin and COP, and maximal PCT. Cut‐off points for the four strongest predictors were calculated by the area under the curve (AUC) in the ROC for the 28‐day mortality.

Results:  Maximal PCT showed the largest AUC (0.85; 95% CI 0.79–0.90) and the highest relative risk (RR 12.17; 95%CI 5.26–28.16; P < 0.001), compared with postoperative albumin (AUC 0.72; 95% CI 0.62–0.81; RR 5.35; 95%CI 2.99–9.56; P < 0.001) and EuroSCORE (AUC 0.73; 95%CI 0.63–0.83; RR 4.48; 95%CI: 1.78–11.28; P < 0.01). By logistic regression, postoperative albumin was the strongest predictor of mortality (odds ratio 0.86; 95% CI 0.84–0.89). Cut‐off values for predicting 28‐day mortality were found for postoperative albumin and PCT at 17.8 g l−1 and 2.5 ng l−1, respectively. A slight but significant inverse correlation between PCT and albumin was found. Patients with albumin less than the cut‐off showed significantly higher median values for PCT levels (2.5 vs. 1.0 g l−1), a higher 28‐day mortality rate (20.8% vs. 4.5%), and a longer ICU stay (6 vs. 3 days) in comparison with patients with minimal albumin greater than 18 g l−1.

Conclusions:  Post‐operative serum albumin <18 g l−1 and PCT  >2.5 ng l−1 are predictive for a higher 28‐day mortality rate in cardiosurgical patients. Both peak PCT and minimal albumin were better outcome predictors than the Euroscore, which better represents the preoperative condition of the patient.