bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of the substrate‐binding exosites of two snake venom serine proteinases: molecular basis for the partition of two essential functions of thrombin
Authors: Maroun R. C. , Serrano S. M. T.
Published: February 2004

The venom of the South American snake Bothrops jararaca contains two serine proteinases, bothrombin and the platelet‐aggregating enzyme PA‐BJ, which share 66% sequence identity. Each of these proteinases possesses one of the two essential procoagulant functions of thrombin—the clotting of fibrinogen and platelet aggregation. Thus, bothrombin clots fibrinogen but has no direct effect on platelets, unless in the presence of exogenous fibrinogen. PA‐BJ induces platelet aggregation by interacting with the protease‐activated platelet receptor without clotting fibrinogen. On the other hand, thrombin possesses two extended surfaces. One is composed of basic and hydrophobic residues (exosite I) and the other one of basic residues only (exosite II). These exosites are involved in the recognition of physiological macromolecular substrates. In order to identify the corresponding exosites in bothrombin and PA‐BJ and understand the molecular basis of the partition of the two procoagulant functions of thrombin among the two snake venom enzymes, we used molecular modeling to obtain models of their complexes with their natural substrates fibrinogen and a fragment of the protease‐activated platelet receptor, respectively. In analogy to thrombin, each of the enzymes presents two exosites. Nonetheless, the exosites contain a smaller proportion of basic residues than thrombin does (45–72%), reducing thus the functional diversity of the enzymes. In addition, the composition of exosite I is different in both enzymes. We identify those residues in exosite I that could contribute to the differences in specificity. Finally, allostery does not seem to mediate macromolecular substrate recognition by these enzymes. Copyright © 2003 John Wiley & Sons, Ltd.
Enhanced recognition of cystic fibrosis W1282X DNA point mutation by chiral peptide nucleic acid probes by a surface plasmon resonance biosensor
Authors: Corradini Roberto , Feriotto Giordana , Sforza Stefano , Marchelli Rosangela , Gambari Roberto
Published: February 2004

Peptide nucleic acids (PNAs) containing an insert of three chiral monomers based on D‐lysine (‘chiral box’) were synthesized and used as probes in Biospecific Interaction Analysis (BIA) for the recognition of DNA containing the W1282X point mutation of the cystic fibrosis gene. Hybridization experiments carried out in solution showed enhanced mismatch recognition when compared with the analogous achiral PNAs and oligonucleotides. The signal intensity was lower, but the selectivity of the Biacore response was found to be much higher than that observed with achiral PNAs. The newly designed chiral PNA probes were also found to hybridize with a 1:1 mixture of normal (N‐W1282X) and mutated (M‐W1282X) DNA oligomers immobilized on the biosensor, thus allowing discrimination not only between a normal and a mutated sequence (healthy/homozygous), but also between homo‐ and heterozygous individuals. These results suggest that ‘chiral box’ PNAs are potential powerful tools for the analysis of single point mutations of biological/biomedical relevance. Copyright © 2003 John Wiley & Sons, Ltd.
Mapping of senescent cell antigen on brain anion exchanger protein (AE) isoforms using HPLC and fast atom bombardment ionization mass spectrometry (FAB‐MS)
Authors: Kay Marguerite M. , Goodman Joseph
Published: February 2004

Molecular recognition of senescent cells involves oxidation of a crucial membrane protein leading to generation of a neoantigen, called ‘senescent cell antigen’ (SCA), and binding of physiologic autoantibodies. These IgG autoantibodies trigger macrophage removal of the cell prior to its lysis at a time when anion transport has decreased but the membrane is still grossly intact. The neoantigen SCA is generated by oxidation of a major anion transport protein called band 3 or anion exchange protein. In this study, we use IgG physiologic autoantibodies from senescent red cells to isolate SCA from brain, and HPLC and fast atom bombardment ionization mass spectrometry (FAB‐MS) to compare brain SCA to band 3. HPLC peptide maps of band 3 and SCA showed substantial homology, suggesting that SCA is a subset of band 3, and includes an estimated ≥45% of the band 3 molecule. FAB‐MS results indicate that residues matching all three band 3 isoforms (AE1, AE2 and AE3) are detected in SCA fractions. These findings suggest that other isoforms of band 3 may undergo the same aging changes that AE1 on red blood cells undergoes to generate SCA. This provides confirmation that SCA is on non‐erythroid cell types. Implications of these studies to the generation of neoantigens by oxidation and their recognition by autoantibodies to them are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Selection of antibody fragments specific for an α‐helix region of acylphosphatase
Authors: Degl'Innocenti Donatella , Taddei Niccolò , Ramazzotti Matteo , Stefani Massimo , Chiti Fabrizio , Ramponi Giampietro
Published: February 2004

The native state of common‐type acylphosphatase (AcP) elicits two α‐helices spanning residues 22–32 and 55–67 in the protein sequence. A peptide corresponding to the second α‐helix (helix‐2) of the protein was used to select phage antibodies consisting of a single chain fragment variable. The selection was performed in the presence of trifluoroethanol, a cosolvent known to induce the formation of helical structure in peptides and proteins. Phage scFv antibodies capable of binding the peptide specifically in a trifluoroethanol‐induced α‐helical conformation were isolated by affinity selection (biopanning). Some of these scFvs were also able to bind the native protein but not the peptide in a non‐helical unstructured state. This indicates that the structural determinant recognized by the selected antibodies is the α‐helical conformation of this specific region, rather than simply its amino acid sequence. This study shows that phage display libraries can be used to raise antibodies one can use as reagents able to target regions of a protein with a specific native‐like secondary structure. Copyright © 2004 John Wiley & Sons, Ltd.
CAD–ICAD complex structure derived from saturation transfer experiment and simulated annealing without using pairwise NOE information
Authors: Matsuda Tomoki , Nakajima Nobuyuki , Yamazaki Toshio , Nakamura Haruki
Published: February 2004

Saturation transfer experiments were performed for the 2H‐ and 15N‐labeled mouse CAD domain of the caspase‐activated deoxyribonuclease and the CAD domain of its inhibitor to reveal the protein–protein complexed conformation. Based on the physical model for the spin diffusion, a novel method was developed to reconstruct the complexed structure using the simulated annealing calculation. The complementarity in the molecular surface shape and the electrostatic potential distribution provide a good measure for the assessment of the putative complexed conformation, despite much less experimental information than the conventional distance geometry calculation. Copyright © 2004 John Wiley & Sons, Ltd.
Differences in growth and yield in response to cadmium toxicity in cotton genotypes
Authors: Wu Feibo , Wu Hongxia , Zhang Guoping , Bachir Dango M. L.
Published: February 2004

A greenhouse hydroponic experiment was conducted to study the effects of cadmium (Cd; 0, 0.1, 1.0, 10 μM in nutrient solution) on yield and yield components as well as Cd concentration and accumulation in three cotton genotypes (Simian 3, Zhongmian 16, Zhongmian 16–2). The results showed that Cd concentration in different organs increased with increasing Cd levels in the nutrient solution in the following order: root > petiole > xylem > fruiting branch, leaf > phloem in vegetative organs and seed coat, seed nut > boll shell > fiber in reproductive organs. There were significant genotypic differences in functional leaf and petiole Cd concentrations at 1 and 10 μM Cd treatments, with the cultivar Simian 3 showing higher Cd concentrations and greater reductions in lint yield than the other two genotypes.
Soil‐plant relationships, micronutrient contents, and cardenolide production in natural populations of Digitalis obscura
Authors: Roca‐Pérez Luis , Boluda Rafael , Pérez‐Bermúdez Pedro
Published: February 2004

The production of secondary metabolites by plants growing in natural populations is conditioned by environmental factors. In the present study, we have investigated the relationships among soil properties, micronutrients in soils and plants, and cardenolide production from wild Digitalis obscura (Scrophulariaceae) populations. Young and mature leaves and soil samples were collected in ten different populations, corresponding to three Mediterranean bioclimatic belts (Thermo‐, Meso‐, and Supramediterranean belts). Soil (total and EDTA‐extractable) and leaf micronutrients (Fe, Mn, Zn, and Cu), and leaf cardenolide accumulation have been determined. Significant negative correlations were observed between Fe, Mn or Zn concentration in leaves and soil pH, as well as between Fe or Mn in leaves and carbonate content of soils. Only EDTA‐extractable Mn was significantly correlated with Mn content in the plants. With regard to cardenolide content in leaves, this parameter was negatively correlated with Znleaf in young leaves and with Mnleaf in old leaves. Positively correlated, however, were Fe and cardenolide content in young leaves. The influence of environmental conditions and leaf micronutrient contents on cardenolide accumulation is discussed.
Vernachlässigte Phosphor‐ und Kaliumdüngung im ökologischen Landbau senkt die biologische Stickstofffixierung bei Rotklee und den Kornertrag bei nachfolgendem Hafer
Authors: Römer Wilhelm , Lehne Philipp
Published: February 2004

In Betrieben des ökologischen Landbaus spielt die biologische Stickstoff (N2)‐Fixierung der Leguminosen die entscheidende Rolle für den N‐Input. Eine nicht ausreichende Versorgung der Leguminosen mit Phosphor (P), Kalium (K) und Schwefel (S) vermindert deren N2‐Fixierungsleistung und damit das Gesamtpotenzial der pflanzlichen Produktion. Um diese Zusammenhänge deutlich zu machen, wurde aus einer Ackerfläche eines Betriebes des ökologischen Landbaus, der seit über drei Jahrzehnten weder Dünger noch Futter zugekauft hat, Boden entnommen und ein Gefäßversuch mit Rotklee und nachfolgend Hafer durchgeführt. Der Boden war ein toniger Schluff (Parabraunerde aus Löss, Südniedersachsen) mit einem pH (CaCl2) von 5,4 sowie 5 mg kg–1 laktatlöslichem P (CAL‐P) und 110 mg kg–1 laktatlöslichem K (CAL‐K). Pro Gefäß wurden dem Boden (Mitscherlichgefäße, 6 kg) 400 mg P als (i) Triplesuperphosphat (TSP), (ii) Rohphosphat (RP), (iii) Bioabfallkompost (BAK), (iv) TSP + 1000 mg K als K2SO4 (TSP+K) bzw. (v) nur 200 mg P als Rohphosphat (RP/2) zugegeben. Eine Kontrollvariante erhielt keinen Dünger.

Die P‐Zufuhr führte zu einer signifikanten Erhöhung des P‐Gehalts in den Rotkleepflanzen und erhöhte deren Trockenmasse (TM)‐Ertrag um 60 bis 130 % sowie die N‐Mengen in den Pflanzen um 64 bis 139 %. Zwischen TSP und RP bestanden keine signifikanten Unterschiede. Der BAK wirkte beim N‐Ertrag signifikant besser als TSP oder RP. Die Variante TSP+K erbrachte bezogen auf die Kontrolle die höchsten Entzüge an P (343 %), K (228 %) und N (239 %) sowie den höchsten TM‐Ertrag (230 %). Dies ist ein Hinweis auf den Synergieeffekt von P, K und S auf die N2‐Bindung, der auch in der Kompostvariante wirksam war. Der nachgebaute Hafer erhöhte seinen Kornertrag auf 132 % (RP/2) bzw. bis auf 165 % (Varianten i–iv). Dies war auf eine erhöhte Kornzahl pro Rispe zurückzuführen. Die Ursachen lagen vor allem in der erhöhten P‐ und N‐Aufnahme (jeweils bis 172 %) des Hafers.
Effects of aerobic conditions in the rhizosphere of rice on the dynamics and availability of phosphorus in a flooded soil – A model experiment
Authors: Zhang Yongsong , Lin Xianyong , Werner Wilfried
Published: February 2004

The secretion of O2 by rice roots results in aerobic conditions in the rhizoshere compared to the bulk flooded soil. The effect of this phenomenon on the adsorption/desorption behavior and on the availability of phosphorus (P) in a flooded soil was investigated in a model experiment. An experimental set‐up was developed that imitates both O2 release and P uptake by the rice root. The results showed that O2 secretion significantly reduced P adsorption/retention and increased P desorption/release in the “rhizosphere” soil, compared to the anaerobic bulk soil. The P uptake by an anion exchange resin from both unfertilized and P‐amended soil was significantly increased.

The results confirm that the O2 secretion is an important mechanism to enhance P availability and P uptake of rice under flooded conditions, where the “physico‐chemical” availability of P in the anaerobic bulk soil is strongly reduced. The decrease of P availability in the P‐amended flooded bulk soil was mainly associated with the almost complete transformation of the precedingly enriched Al‐P fraction into Fe‐bound P with extremely low desorption/release characteristics during the subsequent flooding.
Content and composition of free and occluded particulate organic matter in a differently textured arable Cambisol as revealed by solid‐state 13C NMR spectroscopy
Authors: Kölbl Angelika , Kögel‐Knabner Ingrid
Published: February 2004

The composition of functional light soil organic matter pools of arable Cambisols with a gradient in clay content was investigated. Soil texture differences originate from increasing loess admixture to the parent material (coarse‐grained tertiary sediments). Using density fractionation in combination with ultrasonic dispersion, two types of particulate organic matter (POM) were obtained: (1) free POM and (2) POM occluded in soil aggregates. Both POM fractions were analyzed by elemental analysis (C, N) and CPMAS 13C NMR spectroscopy. With increasing clay content the amount of organic carbon stored in the occluded POM fraction increased considerably, whereas the amounts of free POM were not related to the soil clay content. With increasing soil clay contents increasing proportions of O‐alkyl C and decreasing proportions of aryl C were found for both POM fractions. The occluded POM fraction showed a higher degree of degradation as indicated by lower amounts in O‐alkyl carbon. A lower degree of POM degradation was associated with higher clay contents. Higher soil clay contents promoted the conservation of POM with a low degree of alteration. This effect of soil texture was found to be highly significant when the aryl C : O‐alkyl C ratio was used as indicator for POM decomposition rather than the alkyl C : O‐alkyl C ratio.
Evolution of organic matter added to soils under cultivation conditions
Authors: Madrid Ramon , Valverde Madalena , Guillén Isidro , Sanchez Antonio , Lax Antonio
Published: February 2004

The development of an organic matter (OM) based on mixed sheep manure and peat, when it was incorporated into soils as fertilizer, was studied. The experiment was carried out in soils under almond tree culture, with drip irrigation and non irrigation regimes. Two doses, 10 and 4.5 kg tree–1, were assayed.

Changes in the humic acid fraction one year after incorporation into soils showed oxidation and enrichment in condensed structures, as observed by an increase of the O*:H* ratio and a decrease of the H*:C* ratio, and also by FTIR spectra. The oxidative process was more significant in the coarser textured and also in the non‐irrigated soil. The evolution of the ratios Cext:Cox and CHA:CFA throughout the culture cycle was followed by sampling and chemical analysis of different forms of organic carbon. Evolution of Cext:Cox showed a uniform humification state in the irrigated soil, and a significant decrease in the non‐irrigated soil, at the beginning of the experiment. Curves of CHA:CFA evolution showed changes attributed to mineralization or drainage of the fulvic acids fraction, giving a maximum in spring in both soils and a final increase at the end of the cycle by drainage only in the irrigated soil.
Redox potential of bulk soil and soil solution concentration of nitrate, manganese, iron, and sulfate in two Gleysols
Authors: Mansfeldt Tim
Published: February 2004

While the reduction of nitrate‐N, Mn(III,IV), Fe(III), and sulfate‐S in soil has been studied intensively in the laboratory, field research has received only limited attention. This study investigated the relationship between redox potential (EH) measured in bulk soil and concentrations of nitrate, Mn2+, Fe2+, and sulfate in the soil solution of two Gleysols differing in drainage status from the Marsh area of Schleswig‐Holstein, Northern Germany. The soils are silty‐sandy and developed from calcareous marine sediments. Redox potentials were monitored weekly with permanently installed Pt electrodes, and soil solution was obtained biweekly by ceramic suction cups from 10, 30, 60, and 150 cm depth over one year. Median EH at 10, 30, 60, and 150 cm depths was 470, 410, 410, and 20 mV in the drained soil and 500, 480, 30, and –170 mV in the undrained soil, respectively. A decrease in EH below critical values was accompanied in the soil solutions (pH 7.4 to 7.8) by disappearance of nitrate below 0 to 200 mV, appearance of Mn2+ below 350 mV, and Fe2+ below 0 to 50 mV. Both metals disappeared from soil solution after aeration. In the sulfide‐bearing environment of the 150 cm depth of the undrained soil, however, the sulfate concentrations were highest at such EH values at which sulfate should be unstable. This discrepancy was reflected in the fact that at this depth bulk soil EH was about 400 mV lower than soil solution EH (250 mV). When investigating the dynamics of nitrate, Mn, and Fe in soils, bulk soil EH provides semi‐quantitative information in terms of critical EH ranges. However, in sulfidic soil environments the interpretation of EH measured in bulk soil is uncertain.
Influence of measuring angle, nitrogen fertilization, and variety on spectral reflectance of winter oilseed rape canopies
Authors: Behrens Torsten , Kraft Martin , Wiesler Franz
Published: February 2004

A field experiment with winter oilseed rape was conducted near Göttingen (northern Germany) in the growing season 1998–99. Twelve varieties were compared at two nitrogen (N) application rates (0, 206 kg N ha–1) regarding shoot dry matter production, shoot N content, shoot N uptake (beginning of shooting, beginning of flowering), and seed yield. Canopy reflectance was measured one week before the beginning of shooting and one week before flowering at different wavelengths between 550 and 940 nm using a spectral reflectance sensor, type FAL II. The vegetation indices red edge inflection point (RIP), soil adjusted vegetation index (SAVI), and normalized vegetation index (NDVI) introduced in literature as indicators of growth parameters were calculated from the reflectance values and compared with growth parameters. The results showed that the measuring angle (–45° to 45°) had a significant influence on the calculated vegetation indices. Therefore, the measuring angle should be kept constant during the measurements. Nitrogen fertilization led to an increase of all vegetation indices. The results revealed significant differences between the tested varieties, indicating problems regarding an accurate estimation of the N status of the crop. Consistent differences in the vegetation indices appeared between varieties with extremely different growth parameters. However, no general relationship between growth parameters and vegetation indices of the 12 varieties could be found. Therefore, variety‐specific calibrations are necessary. The indices RIP and SAVI resulted in similar statements and seem to be good parameters regarding N effects and variety differences, whereas NDVI could resolve variety differences in the fertilized treatments only imperfectly.
Genotype x environment interaction in the uptake of Cs and Sr from soils by plants
Authors: Melnitchouck Alexei , Hodson Mark
Published: February 2004

The soil‐plant transfer factors for Cs and Sr were analyzed in relationship to soil properties, crops, and varieties of crops. Two crops and two varieties of each crop: lettuce (Lactuca sativa L.), cv. Salad Bowl Green and cv. Lobjoits Green Cos, and radish (Raphanus sativus L.), cv. French Breakfast 3 and cv. Scarlet Globe, were grown on five different soils amended with Cs and Sr to give concentrations of 1 mg kg–1 and 50 mg kg–1 of each element. Soil‐plant transfer coefficients ranged between 0.12–19.10 (Cs) and 1.48–146.10 (Sr) for lettuce and 0.09–13.24 (Cs) and 2.99–93.00 (Sr) for radish.

Uptake of Cs and Sr by plants depended on both plant and soil properties. There were significant (P ≤ 0.05) differences between soil‐plant transfer factors for each plant type at the two soil concentrations. At each soil concentration about 60 % of the variance in the uptake of the Cs and Sr was due to soil properties. For a given concentration of Cs or Sr in soil, the most important factor effecting soil‐plant transfer of these elements was the soil properties rather than the crops or varieties of crops. Therefore, for the varieties considered here, soil‐plant transfer of Cs and Sr would be best regulated through the management of soil properties.

At each concentration of Cs and Sr, the main soil properties effecting the uptake of Cs and Sr by lettuce and radish were the concentrations of K and Ca, pH and CEC. Together with the concentrations of contaminants in soils, they explained about 80 % of total data variance, and were the best predictors for soil‐plant transfer. The different varieties of lettuce and radish gave different responses in soil‐plant transfer of Cs and Sr in different soil conditions, i.e. genotype x environment interaction caused about 30 % of the variability in the uptake of Cs and Sr by plants. This means that a plant variety with a low soil‐plant transfer of Cs and Sr in one soil could have an increased soil‐plant transfer factor in other soils.

The broad implications of this work are that in contaminated agricultural lands still used for plant growing, contaminant‐excluding crop varieties may not be a reliable method for decreasing contaminant transfer to foodstuffs. Modification of soil properties would be a more reliable technique. This is particularly relevant to agricultural soils in the former USSR still affected by fallout from the Chernobyl disaster.
The automated determination of glucosamine, galactosamine, muramic acid, and mannosamine in soil and root hydrolysates by HPLC
Authors: Appuhn Astrid , Joergensen Rainer Georg , Raubuch Markus , Scheller Edwin , Wilke Brigitte
Published: February 2004

Amino sugars make a significant contribution to soil organic N and are mainly of microbial origin. The most important amino sugars in soil are glucosamine, galactosamine, muramic acid, and mannosamine. A method was developed for the simultaneous determination of these four amino sugars by high‐performance reverse‐phase liquid chromatography in standard solutions, soil and root hydrolysates. Pre‐column derivatization with o‐phthaldialdehyde (OPA) was used in an automated sample injector with thermostatic regulation of the reagent at 4 °C. The separation of the four amino sugars was fully satisfactory and was not disturbed by other fluorescent components in the soil and root hydrolysates.
Characterisation of embalming materials of a mummy of the Ptolemaic era. Comparison with balms from mummies of different eras
Authors: Tchapla Alain , Méjanelle Philippe , Bleton Jean , Goursaud Serge
Published: February 2004

Gas chromatography‐mass spectrometry has been used to determine the nature of organic materials used in mummification balms. A comparative analysis of samples taken from Egyptian mummies is developed. The results are given in two parts. First, it is shown that the chemical composition of the balm is practically independent of the part of the mummy from which it is taken. This study was done on a Ptolemaïc mummy (circa 100 BC from the Guimet Museum in Lyon). Fats, beeswax, and diterpenic resins were the main components: they were found everywhere. Castor oil was also very often detected (in half of the samples). This particular fat is present in the balm inside the thorax but not in the skull. Moreover it is shown that a vegetable tannin was employed. Components indicative of vegetable tannin input (gallic acid and inositols) were found in seven samples out of eighteen, particularly close to the body and on the canopic pack of the heart. Secondly, some conclusions from a comparative study of the composition of balms from mummies of various social levels as well as of different Egyptian periods are reported. It is shown that beeswax was used as from very early times (XVIIIth dynasty). The mixture of beeswax, fats, and diterpenoid resins would appear to be more recent. The balms of three mummies dating from more recent Egyptian periods (XIXth to XXVth dynasty) were analysed. No evidence of a resin, gum‐resin, or plant gum could be found. Some mummies would appear to have been embalmed with fats or beeswax. Finally, the entrails canopic pack said to belong to Ramses II undoubtedly shows an embalming process with a triterpenic resin of the mastic type. The adopted analytical methodology enabled us to achieve simultaneous detection of four components of the balm of the Ptolemaïc mummy. Analysis of the other five mummies revealed far less complex chemical compositions for the balms. This may be an indication of different embalming processes, although we should bear in mind the question of organic matter preservation through the ages.
Headspace solid phase microextraction for screening for the presence of resins in Egyptian archaeological samples
Authors: Hamm Sandrine , Bleton Jean , Tchapla Alain
Published: February 2004

The aim of this study was to use headspace solid phase microextraction (SPME) to reveal the presence of resin in archaeological samples, such as mummification balms, from ancient Egypt. Experiments were first performed with fresh resins of known origin. The SPME fibre readily extracted mono‐ and sesquiterpenes and, to a lesser extent, diterpenes. Using mass spectra and retention indices of constitutive compounds, qualitative analysis of the volatile fraction allowed us to differentiate resins or gum‐resins such as myrrh, olibanum, galbanum, labdanum, mastic, and conifer resins. SPME was then successfully applied to archaeological samples from ancient Egypt in which the presence of resins was detected. Volatile components were desorbed and trapped according to the same SPME procedure as was applied to fresh resins, after a sample preparation consisting of a fine grinding.
Direct chemolysis–gas chromatography–mass spectrometry for analysis of paint materials
Authors: Pitthard Václav , Finch Paul , Bayerová Tatjana
Published: February 2004

A novel direct method using (m‐trifluoromethylphenyl)trimethylammonium hydroxide (TFTMAH) has been developed for on‐line (trans)esterification of lipidic materials (drying oils, egg) prior to GC‐MS analysis. The method was first optimised by comparing three N‐methylammonium hydroxide reagents (TMAH, PhTMAH, TFTMAH) and triolein as a lipid standard. Secondly, the procedure was tested on a series of fresh and naturally aged (up to 40 years) (un)pigmented drying oils and egg yolk reference film standards. Thirdly, the method was applied to the analysis of a sample from an altar painting “Resurrection of Christ” by Francesco Solimena (1723) from the Chapel of Upper Belvedere in Vienna. The relative proportions of the fatty acids from the translucent size layer confirm the presence of partially degraded oil, probably pre‐polymerised walnut oil.
Intensity dependent anomalous transmittivity of thin
plasma layers
Authors: Varró S , Gál K , Földes I B
Published: February 2004

For some time now anomalous transparency induced by
high intensity laser light interacting with thin solid foils has
been found experimentally [1] and several theoretical
models have been suggested to explain this phenomena [2, 3]. In
our present study based mostly on classical electrodynamics the
increase of the transmittivity is the consequence of the more and
more pronounced role of the frustrated total reflection in the
plasma layer. We give a detailed analysis of the effect of the
electron temperature of the plasma and of the angle of incidence
of the laser light on the transmittivity.
On the polarization properties of the micromaser pumped by the atoms
with degenerate levels
Authors: Reshetov V A , Yevseyev I V
Published: February 2004

The polarization properties of the micromaser field
pumped by the atoms with the resonant levels, which are degenerate
in the projections of the total angular momentum on the
quantization axis, are studied numerically. The standard
micromaser operation, when the atoms enter the cavity excited to
the upper resonant level, and the micromaser operation under the
coherent pump, when the atoms enter the cavity in a superposition
of resonant atomic levels, are considered. The treatment is based
on the master equation for the density matrix of the micromaser
field, which takes into account the degeneracy of atomic levels.
Comparison of mid infrared lasers effect on ureter tissue
Authors: Jelínková H , Kőhler O , Němec M , Koranda P , Šulc J , Kubeček V , Drlík P , Miyagi M , Shi Yi-W , Matsuura Y , Kokta M R , Hrabal P , Jelinek M
Published: February 2004

Aim of the work was an investigation of ureter wall
perforation possibility by various types of mid-infrared
radiations (from 2.01 μm (Tm:YAG) up to 2.94 μm
(Er:YAG)) and exploration of the interaction basic characteristic
for ureter surface (epithelium) and its deep structures
(mesenchym). From results follow that Ho:YAG, Er:YAG and CTE:YAG
laser radiations accomplish a good wall ureter perforation. A
distinguished difference appeared in modifications the ureter
tissue - epithelium and mesenchym.
Nonlinear effects in periodic potentials: asymmetric
Landau-Zener tunnelling of a Bose-Einstein condensate
Authors: Jona-Lasinio M , Morsch O , Cristiani M , Malossi N , Müller J H , Courtade E , Anderlini M , Arimondo E
Published: February 2004

From a two-level model for nonlinear Landau-Zener
tunnelling between two energy bands of a Bose-Einstein condensate
in a periodic potential we obtain unequal tunnelling rates for the
two directions of tunnelling. With increasing nonlinearity,
tunnelling from the ground state to the excited state is enhanced,
whereas in the opposite direction it is suppressed. These findings
are confirmed by numerical simulations of the condensate dynamics.
Measuring the tunnelling rates for a condensate of rubidium atoms
in an optical lattice, we have found experimental evidence for
this asymmetry. We discuss the limitations of our approach and
possible future experiments.
Korrelation zwischen im Salzsprühtest sowie in makroskopischen und ortsaufgelösten elektrochemischen Untersuchungen ermittelten Ergebnissen zur Beschreibung des Korrosionsverhaltens von plasmaanodisierten und PVD‐beschichteten Magnesiumlegierungen.
Authors: Hoche H. , Rosenkranz C. , Delp A. , Lohrengel M.M. , Broszeit E. , Berger C.
Published: February 2004

Zur Beschreibung des Korrosionsverhaltens werden unterschiedliche Korrosionsprüfverfahren an PVD‐plasmaanodisierten und zusätzlich PVD‐Al2O3 beschichteten Proben der Magnesiumdruckgusslegierung AZ91D und der für Magnesiumlegierungen optimierten PVD‐Standard‐Hartstoffschicht des Typs CrN angewendet. Für den Salzsprühtest wurden die beschichteten Proben mit dem Ritztest (EN ISO 1071‐3:2000) vorgeschädigt, und die Überlegenheit der plasmaanodisierten und Al2O3 beschichteten Proben wurde eindrucksvoll bestätigt. Die Untersuchung des makroskopischen elektrochemischen Korrosionsverhaltens mit Stromdichte‐Potentialkurven (Prüfdurchmesser 10 mm) erlaubt keine ausreichende Beschreibung der beiden Oberflächenbehandlungen. Eine geeignete Beschreibung des elektrochemischen Korrosionsverhaltens PVD‐beschichteter Magnesiumlegierungen liefern ortaufgelöste Messungen mit einer Kapillarmikrozelle (Prüfdurchmesser 0,15 mm) durch den Vergleich zwischen fehlerfreien Schichtbereichen und gezielt mit Vickerseindrücken geschädigten Stellen.

Die Ergebnisse der drei Prüfverfahren werden gegenübergestellt und in Übereinstimmung gebracht. Es wird gezeigt, dass herkömmliche makroskopische Stromdichte‐Potentialmessungen nicht hinreichend geeignet sind zur Beschreibung des elektrochemischen Korrosionsverhaltens von PVD‐beschichteten Magnesiumlegierungen.
On Lindemann's Melting Criterion
Authors: Hoffmann H.‐J.
Published: February 2004

Lindemann’s empirical melting criterion is applied using data of the solid chemical elements. The respective expression which depends on the melting temperature, the molar mass and the molar volume correlates fairly well with the Debye temperatures. However, it seems incapable to predict inversely the melting temperatures with the other parameters given. Thus, Lindemann’s criterion has no empirical relevance in addition to its scientific deficits.
Zur Statistik in der Betriebsfestigkeit
Authors: Seifried A.
Published: February 2004

Die Festigkeitswerte technischer Werkstoffe können in einem weiten Bereich streuen. Die Bereichs‐Untergrenze, d. h. die Mindestfestigkeit, die einer Konstruktion zugrunde zu legen ist, ist immer deutlich größer als null. Formeln zur mathematischen Beschreibung der Festigkeits‐Verteilung F, müssen diese Mindestgrenze explizit darstellen können. Formeln, die negative oder Null‐Werte als Minimum annehmen, wie Normalverteilung oder 2‐parametrige Weibull‐Verteilung, sind ungeeignet..

Die Standardabweichung hängt von der Größe bzw. dem Volumen der Probekörper ab. Deshalb ist sie kein Charakteristikum für einen bestimmten Werkstoff oder für ein bestimmtes Maschinenelement und die rechnerische Ermittlung von Mindestwerten aus Mittelwert und Standard‐Abweichung von Versuchswerten ist sehr unsicher. Besonders problematisch ist dies bei Kerbproben, wo das maßgebende kritisch beanspruchte Volumen sehr klein ist.

Zur Ermittlung zuverlässiger Mindestwerte ist eine möglichst große Anzahl von Prüfstücken und eine Extrapolation auf die ausfallfreie Zeit bzw. Spannung erforderlich. Die Versuchs‐Laufzeiten kann man reduzieren, wenn man auf die Kenntnis der Standard‐Abweichung verzichtet.

In der Regel ist ein Konstruktionsteil absolut ausfallfrei im Wöhlerfeld auszulegen. Der zulässige Auslegungspunkt muss um einen gewissen Betrag (Sicherheitsfaktor) unterhalb der ausfallfreien Wöhlerlinie F=0 liegen. Restrisiken aus anderen Einflüssen des praktischen Betriebs (unsichere Last‐Annahmen, Umwelt‐Einflüsse, ...), können grundsätzlich nicht aus Betriebsfestigkeitsversuchen abgeleitet werden.
Computation of the matrix exponential and its derivatives by scaling and squaring
Authors: Fung T. C.
Published: February 2004

In this paper, a simple method based on the scaling and squaring technique for the evaluation of the matrix exponential and its derivatives is presented. A more general formulation with non‐constant first derivatives is considered here. Both higher order and mixed derivatives are investigated. The method is based directly on the property of the exponential function and does not require the use of perturbation formulae for eigenvalues and eigenvectors. The approach provides a simple and direct algorithm for the computation of the matrix exponential and its derivatives regardless of degeneracy in the spectral decomposition of the matrix argument. If the derivatives are taken with respect to the entries of the matrix argument, the first and second linearizations can be obtained directly. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical issues in the virtual fields method
Authors: Grédiac Michel , Pierron Fabrice
Published: February 2004

This paper deals with the direct identification of parameters governing anisotropic elastic constitutive equations. These parameters are identified from heterogeneous strain fields with the virtual fields method. This method is based on a relevant use of the principle of virtual work. Different numerical aspects of the implementation of the method are discussed in the paper, mainly in terms of stability of the identified parameters when noisy data are processed. It is shown that the sensitivity of the method to noisy data is compatible with a practical use during experiments. Copyright © 2004 John Wiley & Sons, Ltd.
Assessment and applications of point interpolation methods for computational mechanics
Authors: Liu G. R. , Gu Y. T. , Dai K. Y.
Published: February 2004

Two meshfree point interpolation methods (PIMs), which are based on the polynomial and the radial basis functions, have been proposed recently in addition to the earlier work with the moving least‐squares (MLS) approximation for the field function approximation. However, it is found that PIMs cannot automatically ensure the compatibility of the solution when they are used together with the energy principles. In this paper, issues related to the compatibility of PIMs are studied. A technique of background cell‐based nodal selections and a penalty method are proposed to enforce the compatibility of the solution of PIMs. The patch test is studied in great detail. The convergences and performances are investigated for both conforming and non‐conforming PIMs. It is found that those methods of the PIM family are very easy to implement, and are very efficient in obtaining numerical solutions for problems of computational mechanics. Copyright © 2004 John Wiley & Sons, Ltd.
Fractures of the lower limbs and their secondary skeletal adaptations: a 20th century example of pre‐modern healing
Authors: Neri R. , Lancellotti L.
Published: February 2004

This study focuses on an old male skeleton, which shows severe fractures of the right femur and of the left tibia and fibula. The skeleton, complete and in a good condition of preservation, comes from a Sardinian osteological collection (from the beginning of 1900 AD) with known age, sex and life‐activity. The features of the fractures and pattern of joint disease, enthesis development and enthesopathies have been studied in order to ascertain a possible cause for these traumatic events, the functional implications for postural and locomotory behavior and, finally, the eventual evidence of medical treatment. Copyright © 2004 John Wiley & Sons, Ltd.
Post‐mortem ablation of the heart: a medieval funerary practice. A case observed at the cemetery of Ganagobie Priory in the French Department of Alpes de Haute Provence
Authors: Mafart B. , Pelletier J.‐P. , Fixot M.
Published: February 2004

The skeletal remains of a medieval warrior were found in an 11th century tomb in the church of Ganagobie Priory in the French Department of Alpes de Haute Provence. Examination revealed evidence of multiple injuries including an arrow in the thorax, several sword blows, and a fractured sternum. The chest had been opened probably to allow removal of the heart after the last fatal blow to the skull. Post‐mortem ablation of the heart was a widespread medieval funerary practice among elite classes in northern Europe. Numerous cases have been described involving British and French royalty. The practice was based on a mystical Middle Age belief that the heart was the spiritual and moral centre. After ablation, the heart was buried separately in a high place of holy worship where the living could pray for the salvation of deceased's soul. The rest of the body was sometimes dismembered and boiled to keep only the skeleton. Pope Boniface VIII forbade body boiling in 1299. In France the practice of removing and burying the heart in a sacred worship place continued among royalty, noblemen, and ecclesiastics until the Revolution of 1789. A few cases were reported into the 19th century. Copyright © 2004 John Wiley & Sons, Ltd.
Age‐at‐death assessment using the os pubis and the auricular surface of the ilium: a test on an identified Asian sample
Authors: Schmitt A.
Published: February 2004

This paper reviews the results of blind tests of two morphological methods of age‐at‐death estimation. These tests were performed on a known age‐at‐death and sex sample taken from a collection of a Thai population. The first technique is based on the age related changes of the pubic symphysis according to the Suchey‐Brooks system, and the other concerns the metamorphosis of the auricular surface of the ilium elaborated by Lovejoy and colleagues. This is the first time that these methods have been tested on skeletal material from Asia. The results indicate that, for both methods, bias and inaccuracy increase with age and true age tends to be underestimated. As a consequence, age‐at‐death assessment based on these two techniques should be avoided on Asian archaeological series or forensic cases. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis and interpretation of flint toolmarks found on bones from West Tump long barrow, Gloucestershire
Authors: Smith M. J. , Brickley M. B.
Published: February 2004

West Tump is a Neolithic chambered tomb originally excavated in 1880. The mound was found to contain a mixed skeletal assemblage, the majority of which was disarticulated. Between 2000 and 2001 material from the site including human bone was re‐examined with a portion of this project focused on taphonomic evidence observed on the human skeletal material. Amongst the factors selected for investigation were deliberate toolmarks. Three specimens were identified as exhibiting toolmarks. Analysis demonstrated that the observed features were cutmarks, consistent with the use of flint tools. However those on two of the specimens were found to be both post‐mortem and recent. The cutmarks observed on the remaining specimen, a right clavicle, were identified as having been inflicted during the peri‐mortem period and consistent with decapitation. British Neolithic mortuary practice has been the subject of ongoing debate since the earliest excavations of relevant sites, but until very recently few assemblages from such contexts have been re‐examined and much of the data in use has derived from sources of considerable age and questionable reliability. The selective removal of specific skeletal elements (particularly skulls) has repeatedly been described in the literature regarding the collective funerary monuments of this period. It has often been assumed that such practices took place after the soft tissues had decayed. One of the examples discussed, suggests this may not always have been the case and the potential significance of this finding is discussed in addition to a possible interpretation of the cutmarks seen on the remaining specimens. Copyright © 2004 John Wiley & Sons, Ltd.
Trauma in the city of Kerma: ancient versus modern injury patterns
Authors: Judd M.
Published: February 2004

Injuries, whether accidental or intentional, have incapacitated humans and their primordial ancestors throughout time, although the injury mechanisms have become increasingly more technologically sophisticated. Interpretation of injury aetiology among past peoples is challenging, and often impossible, however, clinical research from developing countries provides a useful analogy with which to evaluate trauma or health patterns of an ancient society. This paper presents a systematic analysis of cranial and postcranial skeletal trauma among 223 adults who were excavated by George Reisner in 1923 from the city of Kerma (1750–1550 BC), Egypt's ancient nemesis in the struggle for control of the Nile River trade route. A total of 156 injuries (fractures, dislocations and muscle pulls among the skull, long bones, extremities and torso) were observed among 88 individuals, 48 of whom had one injury only. The skull was the most frequently traumatized element (11.2%) followed by the ulna (8.3%); 2.4% (48/2029) long bones were fractured.

The modal distribution of the Kerma fractures was compared to the fracture distributions of two samples from India and Nigeria where falls were the most common cause of injury. Some characteristics of the three injury patterns were shared: males suffered the greatest frequency of injury, the economically active people (25 to 50 years of age) presented the most injuries among adults, and a small proportion of the victims had more than one major injury. However, the Kerma distribution of the fractured bones varied dramatically from the clinical injury distributions: the ulna and skull were among the least frequently injured bones in the modern samples, while the radius, humerus and lower leg were the most commonly traumatized elements among the modern people, but rare among the ancients. The configuration of the ulna and skull injuries at Kerma was characteristic of those associated with blunt force trauma in other clinical assessments and the absence of these specific lesions from the modern samples where accident was the primary injury mechanism presents a persuasive argument for interpersonal violence among the ancient Kerma people. Copyright © 2004 John Wiley & Sons, Ltd.
Health‐related behavior and the use of hormone replacement therapy
Authors: Csizmadi Ilona , Collet Jean‐Paul , Boivin Jean‐François , Hanley James A. , Benedetti Andrea
Published: February 2004

Purpose

To study health‐related differences between hormone replacement therapy (HRT) users and nonusers among colorectal cases and women without diagnosed cancer.

Methods

Data from the Saskatchewan Health population‐based databases were used to ascertain the use of HRT, oral contraceptives (OCs), cardiovascular system (CVS) drugs, central nervous system (CNS) drugs, prescribed NSAIDs and vitamins among 3338 women diagnosed with colorectal cancer and 13 025 women without diagnosed cancer. Physician visits and sigmoidoscopy procedures were also determined.

Results

Among women without diagnosed cancer, HRT was associated with CVS drugs (OR=1.23, 95%CI: 1.10–1.37), CNS drugs (OR=1.96, 95%CI: 1.72–2.23), other hormones (OR=1.12, 95%CI: 1.01–1.24), prescribed vitamins (OR= 1.37, 95%CI: 1.22–1.55), NSAIDs (OR=1.41, 95%CI: 1.18–1.68), having had a sigmoidoscopy 3–5 years prior to index dates (OR=1.33, 95%CI: 1.12–1.59) and 15 or more visits to physicians during the 5th year prior to assigned index date (OR=2.0, 95%CI: 1.77–2.35). Similar results were observed among women diagnosed with colorectal cancer, but HRT use was not associated with having had a sigmoidoscopy.

Conclusions

Health‐related characteristics of HRT users and nonusers are identified and described. Some of these factors may contribute to selection bias in studies examining the health benefits of HRT. Copyright © 2003 John Wiley & Sons, Ltd.
Determinants of drug utilisation in a Swedish municipality
Authors: Al‐Windi Ahmad , Elmfeldt Dag , Svärdsudd Kurt
Published: February 2004

Background

The cost for pharmaceuticals is rapidly increasing in most countries. Identification of the characteristics of the population that determine drug utilisation appears essential for the appropriate allocation of resources to caregivers. The primary aim of this study was to identify sociodemographic factors and measures of well‐being and disease that were independently related to the use of drugs, including herbal, and self‐care products in Håbo, a Swedish primary health care district. Another aim was to evaluate combinations of such factors that may improve the prediction of drug utilisation.

Methods

A postal questionnaire was sent to a representative age‐stratified population sample from Håbo. Out of 1312 subjects in the population sample, 827 (63%) answered the questionnaire. The questionnaire contained questions on sociodemographic variables, well‐being and symptoms and use of drugs, herbal and self‐care products.

Results

Chronic disease was the most important of several factors that identified users of drugs. Other important factors were female sex, poor perceived health, sick‐leave or disability pension and a high number of symptoms (complaint score). When combined, these variables could explain 18% of the use of prescribed pharmaceuticals using the logistic regression model.

Conclusion

Several sociodemographic characteristics as well as perceived health, complaint score and chronic disease were independently related to the use of drugs and self‐care products. The likelihood of using prescribed drugs was very high in subjects with a certain profile. Eighteen per cent of the use could be attributed to this profile. Copyright © 2003 John Wiley & Sons, Ltd.