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A modified Johnson-Cook model is proposed to take into account the thermally activated and viscous regimes that can be easily integrated in numerical codes. The model was calibrated using experimental data generated at temperatures ranging from 23 to 1000°C and strain rates ranging from 0.002 to $3 \times 10^{4}$s-1and validated through numerical simulations of symmetric Taylor tests for a pure nickel and a high strength nickel alloy.

L’arrêt du service de portage des traitements rétrocédés aux officines, initié à titre gratuit lors la crise sanitaire à Sars-Cov-2, a encouragé notre centre à souscrire de façon temporaire à un service payant du même type proposé par notre grossiste-répartiteur (COLIPASS® ; OCP). Ce dispositif a été proposé à l’ensemble de nos patients bénéficiant, pour la plupart, d’une rétrocession d’anticancéreux oral. La principale motivation est de limiter les déplacements des patients parfois éloignés, tout en garantissant l’accès sécurisé et la continuité des traitements rétrocédés. Afin de préserver la transmission des conseils lors de la première dispensation, ce service concernait uniquement les renouvellements.

This paper provides two complete sets of shear strength data for smooth HDPE-compacted clay liner interfaces with two significantly different clay liner materials. Data are presented for interface shear strength behavior under as-compacted conditions, and also for conditions representing unconsolidated, undrained shear after sustained presoaking under light surcharges. Samples are tested over a broad range of compaction conditions, and the resulting data show that as compacted HDPE-clay liner interface shear strengths can change by a factor of two or more as a result of relatively minor variations in as-compacted dry density and water content. Moreover, the controlled range of specified field compaction conditions usually employed for waste repository compacted clay liners (in order to optimize ductility and to achieve the low permeabilities mandated by law) appears to encompass the range of compaction conditions over which these significant changes in interface shear strength behavior can occur. In addition, the data peresented show clearly the potentially important impact of wetting of compacted clay liner materials on smooth HDPE-clay liner interface shear strengths.

The differences between the liquefaction triggering correlations published by Seed et al. (1984)and those published more recently by Cetin et al. (2004)and those by Idriss and Boulanger (2004, 2008)are examined in this paper. The case histories, which cause the Cetin et al. correlation of the cyclic resistance ratio, adjusted for M= 7.5 and σv′= 1 atm, to plot significantly lower than those by Seed et al. and Idriss and Boulanger, are examined in detail. The lower position of the Cetin et al. liquefaction triggering correlation is found to be primarily caused by their interpretations and usage for 8 of the 11 key case histories that had controlled the position of their liquefaction triggering correlation. When properly interpreted, these eight case histories no longer support the position of the published Cetin et al. liquefaction triggering curve.

A modified Johnson-Cook model is proposed to take into account the thermally activated and viscous regimes that can be easily integrated in numerical codes. The model was calibrated using experimental data generated at temperatures ranging from 23 to 1000?C and strain rates ranging from 0.002 to 3 ?104 s-1 and validated through numerical simulations of symmetric Taylor tests for a pure nickel and a high strength nickel alloy.

Accurate estimation of inelastic displacements is important for the evaluation of the seismic performance of structures with desired ductile response. In this paper, nonlinear dynamic analyses results from a companion numerical study investigating the response of ductile-designed bridge structures, were compared with a commonly applied inelastic displacement estimation approach and an alternative approach. The extended pile-shaft-supported bridge structures considered are susceptible to amplified response under long-period velocity pulses, and hence an evaluation of design methods for estimating inelastic displacement demands is warranted. In this case, force-reduction–displacement-ductility–period (R−μΔ−T) relations and a mean spectral displacement approach are investigated. The alternative approach estimates inelastic displacement demand using the mean elastic spectral displacement between two spectral periods that are important for the structure's response. Results support the conceptual merits of using the mean spectral displacement method, indicating that the approach is capable of reducing the uncertainty in predicting inelastic displacement demands for the types of structures considered when subjected to near-fault ground motions.

Nonlinear static and dynamic analyses were used to evaluate the inelastic seismic response of bridge and viaduct structures supported on extended cast-in-drilled-hole (CIDH) pile shafts. The nonlinear dynamic analyses used a beam-on-nonlinear-Winkler foundation (BNWF) framework to model the soil-pile interaction, nonlinear fiber beam-column elements to model the reinforced concrete sections, and one-dimensional site response analyses for the free-field soil profile response. The study included consideration of ground motion characteristics, site response, lateral soil resistance, structural parameters, geometric nonlinearity (P-Δ effects), and performance measures. Results described herein focus on how the ground motion characteristics and variations in structural configurations affect the performance measures important for evaluating the inelastic seismic response of these structures. Presented results focus on a representative dense soil profile and thus are not widely applicable to dramatically different soil sites.

The effect of colonization with the vesicular-arbuscular mycorrhizal fungus Glomus etunicatum on the content of rishitin and solavetivone was determined in potato plants cv. Goldrush challenged with Rhizoctonia solani. Mycorrhization stimulated significantly the accumulation of both phytoalexins in roots of plantlets challenged with R. solani but did not influence phytoalexin levels in non-challenged plantlet roots. No accumulation of solavetivone or rishitin was detected in shoots. In Petri dish bioassays, rishitin and solavetivone inhibited mycelial growth of R. solani.

Forty‐five volatile compounds were identified and 14 tentatively identified in cupuaçu (Theobroma grandiflorum) pulp using solid phase extraction on XAD‐2 and simultaneous distillation extraction. Among them, 35 compounds were reported for the first time in this fruit. The olfactive characteristics of several compounds, separated after solid phase extraction, and their odour activity values showed that linalol, α‐terpineol, 2‐phenylethanol, myrcene, and limonene were contributors of the cupuaçu pleasant, floral flavour. Ethyl 2‐methylbutanoate, ethyl hexanoate and butyl butanoate were involved in the typical fruity characteristics of cupuaçu. Diols (2,6‐dimethyl‐oct‐7‐en‐2,6‐diol. (E)‐2,6‐dimethyl‐octa‐2,7‐dien‐1,6‐diol, and its (Z) isomer) and methoxy‐2,5‐dimethyl‐3(2H)‐furanone were possible contributors of the typical exotic odour. Moreover, hexadecanoic acid can be considered as a contributor of the grassy, heavy odour of cupuaçu. Copyright © 2000 John Wiley & Sons, Ltd.

Forty-five volatile compounds were identified and 14 tentatively identified in cupuaçu (Theobroma grandiflorum) pulp using solid phase extraction on XAD-2 and simultaneous distillation extraction. Among them, 35 compounds were reported for the first time in this fruit. The olfactive characteristics of several compounds, separated after solid phase extraction, and their odour activity values showed that linalol, α-terpineol, 2-phenylethanol, myrcene, and limonene were contributors of the cupuaçu pleasant, floral flavour. Ethyl 2-methylbutanoate, ethyl hexanoate and butyl butanoate were involved in the typical fruity characteristics of cupuaçu. Diols (2,6-dimethyl-oct-7-en-2,6-diol. (E)-2,6-dimethyl-octa-2,7-dien-1,6-diol, and its (Z) isomer) and methoxy-2,5-dimethyl-3(2H)-furanone were possible contributors of the typical exotic odour. Moreover, hexadecanoic acid can be considered as a contributor of the grassy, heavy odour of cupuaçu. Copyright © 2000 John Wiley & Sons, Ltd.

Difficulties in isolating and purifying antibiotic fatty acids from culture filtrates of Pseudozyma flocculosa, a biocontrol agent against powdery mildew, have been limiting factors in studying the properties and understanding the mode of action of the biocontrol agent. We report a new protocol for synthesizing (Z)-9-heptadecenoic and for the first time synthesis of (Z)-6-methyl-9-heptadecenoic acids, two antibiotic fatty acids produced by P. flocculosa.This allowed reproducible and quantifiable means of assaying biological activity of the molecules. In these bioassays, both molecules exhibited antifungal activity corresponding to their expected potency. These new developments should facilitate further studies aimed at deciphering the ecological properties of P. flocculosa.

The free and bound flavour components of bacuri fruits were analysed by capillary GC and GC–MS following XAD-2 separation. Seventy-five components were identified in the free volatile fraction; the most abundant were terpene alcohols, among them, linalol and related compounds, linalol furanoxides and pyranoxides, hotrienol and several dimethyl-octadiendiols. Abundant amounts of 4-methoxy-2,5-dimethyl-3(2H)-furanone were also found. Seven glucosides and three rutinosides were identified by GC–MS of their TFA derivatives for EI–MS and NCI–MS, in agreement with quantitative data obtained for enzymatically released aglycones and saccharidic moieties structure; the most important glycosides were benzyl, 2-phenylethyl, (E)-linalol furanoxide and (S)-linalol glucosides and benzyl, 2-phenylethyl, and (S)-linalol rutinosides. Glycosides possessing ‘unusual’ saccharidic moieties remained unidentified. Copyright © 1999 John Wiley & Sons, Ltd.

The free and bound flavour components of bacuri fruits were analysed by capillary GC and GC–MS following XAD‐2 separation. Seventy‐five components were identified in the free volatile fraction; the most abundant were terpene alcohols, among them, linalol and related compounds, linalol furanoxides and pyranoxides, hotrienol and several dimethyl‐octadiendiols. Abundant amounts of 4‐methoxy‐2,5‐dimethyl‐3(2H)‐furanone were also found. Seven glucosides and three rutinosides were identified by GC–MS of their TFA derivatives for EI–MS and NCI–MS, in agreement with quantitative data obtained for enzymatically released aglycones and saccharidic moieties structure; the most important glycosides were benzyl, 2‐phenylethyl, (E)‐linalol furanoxide and (S)‐linalol glucosides and benzyl, 2‐phenylethyl, and (S)‐linalol rutinosides. Glycosides possessing ‘unusual’ saccharidic moieties remained unidentified. Copyright © 1999 John Wiley & Sons, Ltd.

A cyclic triaxial testing system capable of measuring very small to large strain properties on a single specimen has been developed by combining a wide variety of existing instrumentation, including piezoceramic bender elements, internal displacement measurement devices (both contact and noncontact), local displacement measurement devices, a sensitive internal load cell, and an external load cell. The bender elements provide information on soil properties in the nearly linear elastic (very small strain) range. Local and noncontact internal displacement measurements provide information about small strain range properties, whereas more traditional internal displacement measurements provide information in the small to large strain range. In addition, this apparatus can be used over a wide range of loading frequencies to investigate the effect of frequency on dynamic soil properties. By combining this equipment in a single testing system, a number of tests may be run on one specimen, eliminating the effects of variability. The broad variety of displacement measuring instruments also allows direct comparisons of these techniques on a single specimen.

A cyclic triaxial testing system capable of measuring very small to large strain properties on a single specimen has been developed by combining a wide variety of existing instrumentation, including piezoceramic bender elements, internal displacement measurement devices (both contact and noncontact), local displacement measurement devices, a sensitive internal load cell, and an external load cell. The bender elements provide information on soil properties in the nearly linear elastic (very small strain) range. Local and noncontact internal displacement measurements provide information about small strain range properties, whereas more traditional internal displacement measurements provide information in the small to large strain range. In addition, this apparatus can be used over a wide range of loading frequencies to investigate the effect of frequency on dynamic soil properties. By combining this equipment in a single testing system, a number of tests may be run on one specimen, eliminating the effects of variability. The broad variety of displacement measuring instruments also allows direct comparisons of these techniques on a single specimen.

The frequency of infection at the time of admission with upper gastrointestinal haemorrhage has been determined in 149 successive cirrhotic patients admitted to an intensive care unit. Infection status was investigated by clinical examination, chest X-ray, and blood, urine and ascitic fluid culture. At initial examination infection was present in 32 patients (22 per cent) and was often in the form of septicaemia or spontaneous peritonitis; the bacteria responsible were frequently digestive in origin. At endoscopy, acute lesions of gastroduodenal mucosa were more frequent among infected patients, whereas gastro-oesophageal varices and chronic gastroduodenal ulcers were more frequent among the non-infected patients. Acute mucosal lesions were observed in 70 per cent of infected patients and in 19 per cent of non-infected patients. The mortality rate was higher in infected patients. Infection and the frequency of acute mucosal lesions were related to the severity of the cirrhosis. It is suggested that these lesions could be due to stress secondary to infection.

The one‐step spirocyclization of the title compounds (I) opens a route to the benzoxazinones and pyridooxazinones (III), which is more efficient than previously reported routes.

1,4‐Di(bromomagnesio)pentane (II) reacts with some lactones or cyclic anhydrides such as (I), (IV), or (VI) to give mixtures of stereoisomeric alcohols such as (III), (V), or (VII).

Treatment of the anhydrides (I) with the title reagents (III) or (IV) gives cycloalkanols (II) or (V), the former products being obtained in higher yields.

The reactions of the title Grignard (II) with a variety of lactones and cyclic anhydrides such as (I), (V) or (VIII) are described.