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Two groups of cells, one rounded or oval and the other spindle-shaped, were found in a case of plexiform fibrohistiocytic tumor. Immunohistochemistry was strongly positive for alpha smooth muscle actin in most cells of both types but stronger in the spindle-shaped cells, suggesting a myofibroblastic origin. This was in correlation with electron microscopic findings which revealed fibroblasts, myofibroblasts and some undifferentiated mesenchymal cells. However, factor XlIIa was negative suggesting that this tumor does not originate from dermal dendrocytes.

Closely–spaced footings may be encountered on cohesionless soils in the form of grillage foundations and railway ties. Close spacing is known to permit higher loads than can be carried by similar isolated footings. This effect is due to interference between failure zones in the sand, and may increase the capacity by 150% when ø = 35° and the centreline separation of the footings is approximately twice the footing width B. The method of stress characteristics has been used to calculate the theoretical bearing capacity of a series of parallel footings, and these have been compared with laboratory tests on three parallel surface footings at various spacings on two different sands. The testing programme also investigated the effects of footing roughness and load distribution. When interference occurs, pre-failure settlements become larger, and post-failure behaviour more ductile. The theoretical solutions show similar trends to the model tests, but suggest that interference stops at rather smaller spacings. Des semelles rapprochées se rencontrent parfois dans le cas de fondations à grillage ou de traverses de chemin de fer sur des sols pulvérulents. On sait qu'un tel écartement permet des charges plus importants que celles qui peuvent etre supportées par des semelles semblables isolées. Cet effet est dû à l'interférence entre les zones de rupture dans le sable et il peut augmenter la force portante de 150% lorsque ø = 35° et la distance entre les centres des semelles est approximativement deux fois leur largeur B. La méthode des caractéristiques de contrainte a été employée pour calculer la portance théorique d'une série de semelles parallèles. Les résultats one été comparés avec ceux obtenus à partir de plusieurs essais faits en laboratoire sur trois semelles superficielles d'écartements variable sur deux sables différents. Les effects de la rugosité des semelles et de la distribution des charges one été etudiés aussi au cours du programme d'essais. Lorsque l'interférence a lieu les tassements précedant la rupture s'accroissent, et le comportement suivant la rupture devient plus ductile. Les solutions théoriques montrent des tendances similaires à celles trouvées dans les essais sur modèles, tandis qu'elles suggérent que l'interférence cesse è des écartements un peu plus faible.

In a double-blind, parallel trial which lasted 1 week and comprised eighty-eight patients, a study of the response to topical therapy of the infected component of four common eczematous processes showed that the treatment outcome with corticosteroid antimicrobial creams was not influenced by the type of dermatitis. The cream with fluocinonide 0.05% was significantly better than the cream with triamcinolone 0.1%. Both creams were clinically superior to a cream containing only the antimicrobial agents but exerted a similar antimicrobial activity.

Twelve repeated load drained triaxial tests to at least 105 cycles on a sand are reported. A threshold stress of about 50% of the static failure strength was found. Below the threshold stress, the permanent deformation and resilient modulus reached constant values. Above the threshold stress, the permanent deformation began to increase rapidly and the resilient modulus to decrease as the number of stress cycles increased. The importance of keeping the traffic stress in the pavement below the threshold stress is outlined.

Repeated load drained tests on Leda clay, as related to subgrade performance, are reported. A threshold stress divided the performance into failing and stable specimens. For the stable specimens the resilient modulus attained equilibrium at about 105 cycles but varied with stress level. Permanent strains continued even at low stresses.

Research has been conducted over the last several years on the use of geotextiles for mainline heavy tonnage railroad tracks. A wide range of geotextiles was observed to provide improvements in many short-term applications. However, many of these improvements were not long lasting. For longevity of the application a much greater discrimination between geotextile types, geotextile weight, polymer types, and fiber denier was found to be desirable. Also found important was the necessity to match the geotextile properties with the soils engineering properties and to follow correct construction procedures.Drainage was found to be the most critical aspect for achieving long-term stability in the track structure. Excess moisture within the roadbed was found to reduce the subgrade strength and provide easy access for fine grain soils to foul the open ballast. Proper drainage techniques combined with geotextiles are given special consideration.Conclusions are drawn regarding the desirable attributes that should be specified in preparing quality requirements for geotextiles to be obtained under conditions of competitive tendering. Keywords: geotextiles, synthetic fabric, fabric, railroad, tracks, track support, rehabilitation, soil mechanics.

Permanent way support systems (roads, airfields, railways) subject to moving load, soil deposits subject to earthquakes, and soil beneath offshore structures subject to wave loading are classical examples of field situations where the soils will experience varying degrees of principal stress rotation. To assess the effects of this principal stress rotation, comparisons were made between the responses of a dry sand when subjected to stress-controlled repetitive triaxial and repetitive simple shear testing. Based on findings from this test program, an attempt was made to analyse the deformation response of a model footing simulating the railway field situation.Principal stress rotation was shown to be a major factor influencing the behaviour of dry granular material when subjected to repetitive load, the effect of which was to induce permanent deformation while the elastic response remained unchanged. The applicability of repetitive triaxial and repetitive simple shear testing in these circumstances is shown to be complex, and rational design methods for field situations involving repetitive loads have been reevaluated. Key words: principal stress rotation, repetitive load, repeated load, cyclic load, granular, triaxial test, simple shear test.

The undrained foundation performance of two embankments, one on a varved clay and one on a sensitive Leda-type clay, is presented with theoretical reasoning for the observed behaviour. In addition, the laboratory and field test results are presented and the undrained properties selected. The undrained stress-strain properties used in the analyses were obtained by combining the consolidated undrained failure index (axial stress difference/axial failure stress difference)-strain relationship with the in situ soil strengths. The pore pressure coefficients A were obtained from triaxial tests done using an initial hydrostatic effective confining pressure, ½–¾ of the preconsolidation pressure. The undrained soil properties were used in conjunction with a finite element computer program which can deal with non-linear cross-anisotropic elasticelements. The choice of undrained properties made is substantiated by a comparison of the predicted and field performance of the embankment foundations. Both undrained settlements and generated excess pore pressures are discussed and conclusions are drawn regarding the selection of the undrained properties and the desirability of accounting for the non-linear nature of the stress-strain relationship. On présente les résultats d'une analyse des fondations non drainées de deux remblais executés l'un sur une d'argile stratifiée, l'autre sur une argile sensible au remaniement du type Leda, ainsi qu'une justification théorique des comportements observés. En outre, on présente les résultats d'essais au laboratoire et in situ, ainsi que les caractéristiques non drainées retenues. Les caractéristiques non drainées contrainte-déformation dont on s'est servi lors des analyses ont été obtenues en combinant la relation: critère de rupture non drainée sur échantillon consolidé (différence des contraintes axiales/différence des contraintes axiales à la rupture)-déformation, aux résistances des sols in situ. On a obtenu ies coefficients de pression interstitielle A à partir des essais de compressions triaxiales que l'on a effectués en se servant d'une pression hydrostatique effective initiale égale à ½-¾ de la pression de préconsolidation. On a utilisé les caractéristiques non drainées du sol concurremment avec un programme sur ordinateur utilisant la méthode des éléments finis, pouvant tenir compte d'éléments élastiques anisotropes non-lindairés s'entrecroisant. Le choix des caractéristiques non drainée est justifié, au moyen d'une comparaison entre le comportement prévu et réel des remblais. On présente une discussion des tassements non drainée et de l'accroupement de pressions interstitielles correspondant, et on tire des conclusions sur le choix des caractéristiques non drainée et sur la necessité de tenir compte de la nature non-linéaire des relations contrainte-déformation.

Synopsis A theory of non-linear consolidation for oedometer boundary conditions has been developed assuming the coefficient of consolidation to be constant, Darcy's Law to be Valid, and the soils obey the law The solutions show that for oedometer boundary conditions Terzaghi's theory predicts satisfactory the rate of settlement but not the rate of dissipation of pore pressures. Terzaghi's solution for the latter case is on the unsage side. Experimental results are presented which show the validity, for normally consolidated clay, of the new theory. On a développé une théorie de consolidation non-linéaire des conditions limites œdométriques en admettant que le coefficient de consolidation soit constant, que la Loi de Darcy soit valable et que le sol obéîsse à la loi Les solutions montrent que pour des conditions limites œdométriques, la théorie de Terzaghi prédit convenablement la vitesse tassement mais pas la vitesse de disparition de la pression interstitielle. La solution de Terzaghi pour ce dernier cas est plutôt douteuse. On présente les résultats expérimentaux qui montrent la validité de la nouvelle théorie pour de l'argile consolidée normalement.

Synopsis Synopsis Under embankments and earth dams the load ratio will generally be greater than two (the standard oedometer ratio) to a depth of twice the embank- ment height. In deep deposits large variations in compressibility and permeability will occur through- out the depth of the deposit. In order to help account for these variations a theory and solutions are presented to cover a large number of practical problems involving one-dimensional drainage for a homogeneous soil which obeys the relationship The theory presented often predicts large differences from rates of consolidation which might have been predicted from the assumptions of the standard linear theory. An approximate method of applying the theory to the consolidation of soils by drain wells is presented. Two case records are referred to which show variation from the linear theory predictions which could be accounted for by the theory pre- sented. Sous des remblais et des barrages en terre le taux de chargement est en g énéral supérieur à deux (le taux mdométrique standard) à une profondeur du double de la hauteur du remblais. Dans les dépôts profonds de grandes variations de compressibilité et de perméabilité se produisent dans toute la profon- deur du dépot. Afin d'aider à expliquer ces varia- tions, une théorie et des solutions sont présentées pour couvrir un grand nombre de problèmes pratiques entraînant un drainage à une dimension pour un sol homogène qui suit le rapport La théorie présentée prévoit souvent de grandes différences avec les taux de consolidation qui auraient pu être prévus a partir des suppositions de la théorie linéaire standard. On présente une méthode approximative d'appliquer la théorie à la consolidation des sols au moyen de puisards. Deux cas enregistrés sont rappelés qui font apparaître une variation par rapport aux prévisions de la théorie linéaire qui pourrait être expliquée par la théorie présentée.

The principal aim of this paper is to compare laboratory settlement and pore pressure dissipation rates of undisturbed Leda clay with those predicted from a modified consolidation theory developed by Raymond (1966a). The theoretical curves have been computed using directly measured values of the soil permeability and incorporate the variation with void ratio of both permeability and compressibility. The experimental data (obtained from the triaxial apparatus) indicate that the predicted rates of consolidation, and especially of pore water dissipation, are likely to be grossly in error owing to the cemented nature of the soil structure. This factor appears to be partially described by the theory of Barden (1965), although quantitative evaluation of the constants involved in this theory has not been possible.The paper also considers two other aspects of the consolidation of Leda clay. (1) The rate of secondary consolidation varies significantly with consolidation pressure and appears to reflect the changes in compressibility revealed by the void ratio vs. log pressure curve. (2) The variation of soil properties with depth at the Ottawa treatment plant site influences all aspects of the consolidation behaviour of the clay.Available field data have been included in the paper where relevant to the discussion.

Under field loading conditions, the consolidation of a clay layer is likely to take place under effective principal stress ratios (σ1′/σ3′), which vary from point to point throughout the soil mass. From a consideration of idealized stress paths, an estimate is made of the effect of stress ratio on rates of volumetric strain and excess pore water pressure dissipation. These predictions are partly supported by data obtained from anisotropic consolidation tests on Leda clay, the major disagreements being due to the significant influence of structural cementation on the rate process.The experimentally observed rates of shear strain have been analyzed in terms of stress-dilatancy concepts. The plastic strain-increment ratio was shown to be a unique function of effective stress ratio, thus confirming the validity of previous work on remoulded clays. A theoretical prediction of this relationship postulated by Burland (1965) did not approximate to the experimental data, due probably to the influence of secondary deformations. The data did, however, show a relationship similar in form to that derived by Walker (1969) for the secondary deformation of remoulded kaolin.

In a multiclinic double-blind trial, 305 patients with moderate to severe acne vulgaris were treated with oral tetracycline hydrochloride, 250 mg (N: 103), a 1% solution of clindamycin phosphate (N: 105), or placebo (N: 97) twice daily for 8 weeks. The response to treatment was evaluated by lesion counts and overall clinical improvement at 2, 4, 6, and 8 weeks. Both topical clindamycin and oral tetracycline significantly reduced papule and pustule counts compared to placebo; they were rated significantly higher than placebo on the physician's and the patient's overall evaluation at the end of the treatment period. No serious side effects were reported with any of the study medications.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

A new case of unilateral dermatomal superficial telangiectasia (UDST) is described, bringing the number of reported cases to 48. This case is unusual in that there was no underlying systemic disorder and no correlation between the onset of the disease and the physiologic hormonal states that have frequently been reported with the acquired type of UDST. The etiopathogenetic mechanisms of this disorder are discussed.

The paper is a welcome addition to the number of experimental projects in sand reported from Canada in recent years. The authors are to be complimented on the fundamental nature of the question they have chosen to examine, on the elegance of the design of their testing program, and on the quality of their results for two interfering footings. Consideration of a closely similar interference problem between three parallel footings (Graham et al. 1984) permits comments to be made on several points raised by the authors. In these three-footing tests, the stress fields associated with the outer footings caused the stresses under the central footing to be symmetrical, as they would be, for example, in a line of parallel interfering footings. This contrasts with the asymmetric stresses under the authors' footings. Separate series of tests in the writers' laboratories have examined how loads are shared between neighbouring footings through superstructures of different stiffnesses. Prefailure and failure conditions have both been studied. In one series (Fig. la), the footings were forced downwards together by a rigid loading system, and the distribution of loads between them was measured by separate load cells. The ratio h of the load on the outer footing to the load on the central footing did not vary greatly between the beginning and end of the tests. In the second series (Fig. lb), the central footing was independent of the outer footings, and different values of )I were held constant durinn the tests. The results L 2

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study. By considering compression to occur only due to water leaving the soil it was possible to derive an expression for the dissipation of pore pressure in the secondary phase. By further simplified assumptions which are based on experimental observations, the above general solution was reduced to a simple formula which predicted the observed behaviour of pore water pressures during secondary consolidation.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study. By considering compression to occur only due to water leaving the soil it was possible to derive an expression for the dissipation of pore pressure in the secondary phase. By further simplified assumptions which are based on experimental observations, the above general solution was reduced to a simple formula which predicted the observed behaviour of pore water pressures during secondary consolidation.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study. By considering compression to occur only due to water leaving the soil it was possible to derive an expression for the dissipation of pore pressure in the secondary phase. By further simplified assumptions which are based on experimental observations, the above general solution was reduced to a simple formula which predicted the observed behaviour of pore water pressures during secondary consolidation.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study. By considering compression to occur only due to water leaving the soil it was possible to derive an expression for the dissipation of pore pressure in the secondary phase. By further simplified assumptions which are based on experimental observations, the above general solution was reduced to a simple formula which predicted the observed behaviour of pore water pressures during secondary consolidation.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study.

This paper describes the work carried out to investigate the pore pressures occurring in secondary consolidation. A theoretical approach and an experimental technique was developed in order to conduct the study. By considering compression to occur only due to water leaving the soil it was possible to derive an expression for the dissipation of pore pressure in the secondary phase. By further simplified assumptions which are based on experimental observations, the above general solution was reduced to a simple formula which predicted the observed behaviour of pore water pressures during secondary consolidation.