The design implication of stress-confinement effect of nonwoven geotextile is addressed. The unconfined and confined strengths of a selected needle-punched nonwoven geotextile are used to conduct a comparative design of a granular soil retaining wall based on a limit equilibrium approach. A higher wall may be allowed when considering the confined strength as compared to the unconfined strength. For a selected wall height, confined strength allows for fewer geotextile layers when compared to that designed using unconfined strength. It is recommended that stress-confinement test procedure should be standardized so that confinement effect of some nonwoven geotextiles may be incorporated into an individual wall design procedure.

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The ability of Climacodon septentrionalis to immobilize and kill a mycophagous nematode (Aphelenchoides sp.) in vitro is described for the first time. Two isolates produced droplets (20–45 μm in diameter) that formed at the apices of tall, stalked, and branching secretory cells (700–1,500 μm tall). On 2% modified malt extract agar, nematodes became enveloped in the droplets, which restricted their ability to move and resulted in complete immobilization and death within several hours of contact. The rate of decomposition of the nematodes varied considerably, with most individuals persisting for weeks whereas others were degraded within several days and appeared to be colonized by dense hyphal growth. This study provides the first documentation of a non-agaricoid fungus producing secretory cells that are able to immobilize nematodes.

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Some existing analytical methods which have been used in geotechnical engineering are modified to handle the shear strength reduction with time due to softening in fissured, over-consolidated clays and mudstones. These are limit equilibrium analysis of slope stability, calculation of earth pressure and calculation of stress and displacement around a tunnel. The softening effect is incorporated in these analyses using the failure criterion and the time-dependent strength parameters proposed previously by the authors. Examples are presented which emphasize the importance of appreciating the softening effect in analyses and further illustrate that the effect of shear strength reduction with time due to softening could easily be captured with existing analytical methods.

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It has been shown after mathematical and mechanical investigation that Limit Equilibrium Method (LEM) can be considered as a method to obtain the necessary condition of Slip Line Method (SLM), and that the solution can be obtained under the condition that F_s=1 and ∂F_s/∂θ=O, where F_s is the safety factor and θ is the inclination of the plane on which the safety factor is defined. Next, the generalized LEM (GLEM) is proposed, dealing with the following points : (1) Triangular or quadrangular blocks can be treated; (2) Safety factors are defined also on interblock planes; and (3) All types of plastic problems, slope stability, bearing capacity, and earth pressure are identically formulated. Two situations regarding treatment of the moment equilibrium condition are discussed. GLEM is applied to well-known problems. The results agree well with those obtained by theoretical methods. GLEM can be used to obtain the distribution of earth pressure or bearing capacity. GLEM, Iike ordinary LEM, is very effective for the practical problems, but GLEM is more theoretical and it can result in more accurate solutions.

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An empirical equation in use for estimating the pseudo-elastic shear modulus, G_f, of subsoil, associated with shear strains less than .001% is proposed in this paper. In a series of in-situ seismic cone tests performed nationwide, the profiles of both G_f and the in-situ void ratio, , with depth were successfully characterised at five sites, each comprising a soft clay layer deposited in the Holocene era. The database which comprised the original data from the field and laboratory tests, coupled with similar information on well-documented Holocene clay deposits in Europe, was statistically analyzed in attempts to determine a generalised relationship with which G_f of soft clay may be reasonably estimated only from routinely available borehole data; that is and the current geostatic effective overburden pressure, σ'_v. An empirical relationship, G_f=, 000 -√(σ'_v) (kPa), was derived from the statistical analysis applied to data from seven different clays worldwide, for which extended over a range between 1 and , and the overconsolidation ratio ranged roughly between 1 and 2. The applicability of the proposed relationship was evaluated for two case records, each in which the clay exhibited unusual behavior; i.., the undrained shear strength remained more or less constant with depth due to the existence of artesian pressure at one site, and, at the other, G_f decreased, whereas increased, with depth. It was demonstrated that even in these clay deposits exhibiting exceptional profiles, the proposed relationship was capable of predicting G_f with a reasonable accuracy by determining the profiles of and σ'_v with depth. In addition, the prediction when compared to G_max from carefully performed laboratory cyclic tests, yielded a better estimate of G_f from the in-situ seismic survey. Despite the fact that the empirical relationship was initially designated to estimate G_f of soft clays, it may be equally applicable to sandy deposits. This was verified by comparing it to similar, and well-established, relationships developed for sands. A case record as such is also described for a loose sand deposit at Higashi-Ohgishima in Tokyo Bay which was placed in 1960's by land reclamation.

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背景と目的：ステロイド性骨粗鬆症は，積極的な治療介入が必要とされる．その第一選択薬はビスホスホネート製剤（以下ビス）であるが，近年，デノスマブ（以下デノス）も注目を浴びている．ステロイド性骨粗鬆症の骨密度に対する両者の効果を比較検討した．

方法：ステロイド性骨粗鬆症の管理と治療ガイドライン：2014年改訂版の薬物療法開始の基準を満たした患者を対象とした．無治療群（N群）と，治療介入群として当初よりビスで治療したBB群，ビス後デノスに変更したBD群，デノスで治療したDD群，デノス後ビスに変更したDB群を抽出し，ステロイド投与を開始した時，ステロイド性骨粗鬆症に対する治療を開始した時または薬剤変更から

カ月後の腰椎，大腿骨頚部と大転子部の骨密度を測定し，それらの変化を統計学的に比較検討した．

結果：149例が抽出され，その内訳は，N群48例，BB群24例，BD群

例，DD群21例，DB群34例であった．治療開始時または薬剤変更からカ月後にBD群を除くすべての治療介入群で腰椎の骨密度が上昇した．大腿骨の骨密度は，BD群において薬剤変更後に上昇に転じた．

考察：デノスにはビスと同様の骨密度上昇効果があると考えられた．

結論：デノスは，ステロイド性骨粗鬆症治療の第一選択薬となり得る．

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This paper reports deformation and strength characteristics for a geogrid-reinforced granular soil on a large-scale plane strain compression apparatus. The influence of intensity and types of geogrid reinforcement is specifically discussed. It was found that as more reinforcement layers are used, the strength of the reinforced soil increased. In cases where reinforcement is most intensely used, the reinforcement layers in the samples were eventually subject to breakage due to plane strain compression and the reinforced soil failed. In cases where reinforcement is less intensely used, the reinforced soil reached failure without any sign of reinforcement breakage. It was also found that types of reinforcement have a significant influence on the lateral deformation of the reinforced soil, where stiffer reinforcement provides more constraints on lateral deformation of the reinforced soil. It can be superceded, however, by the influence of reinforcement intensity. The small stain measurement by means of LDT observed that the stiffness of non-reinforced soil begins to decrease more rapidly at a strain level of .05∼.15%, compared to the reinforced soil. The experimental results also indicate that the relationship between the apparent angle of internal friction and the geometry of the structure of the reinforced granular soil seems to exist for the geogrid reinforcement used in the tests reported in this paper.

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We observed transients during the isotopic analysis of carbon dioxide, which could not be attributed to mixing processes because of their asymmetry, and to explain these we were led to consider the effects of diffusion on gas flow in the sample line. In particular, we investigated the propagation by diffusion of a concentration anomaly against a steady gas flow. If fractionation of isotopic(or chemical)species at the leak is to cause a change with time of the composition of the gas in the sample reservoir, then the effects of the fractionation must diffuse backwards as far as the gas reservoir.Using a one-dimensional Green's function, we obtained explicit analytical functions for the steady state concentration variation along a connecting tube between the leak and the reservoir, and for the composition variations with time at the leak. It is shown that the isotopic composition in the sample reservoir need not vary with time, even with a fractionating leak, provided that bulk gas velocity in the connecting tube is large enough. It is also shown that the diffusion process in combination with a fractionating leak can lead to the type of transients we observed.

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This paper outlines a mathematical description of the stress dilatancy behaviour of granular materials which accounts for stress level and void ratio dependencies. The consideration of these aspects has important implications in the modelling of granular material behaviour. In fact, granular material mechanical response is largely dominated by the evolution of dilatancy, fabric and void ratio histories. The starting point in this study is the well established Rowe's theory which is revisited and ultimately modified by introducing a factor linked to governing state parameters in order to describe the complete behaviour of granular materials during deformation. Numerical simulations of triaxial tests on granular materials at different void ratios and stress levels are herein presented to illustrate the model.

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In this paper, consideration is given as to how to characterize depth-variation for the small-strain shear modulus of natural clay sedimentation, in a state of normal consolidation. A case study was carried out for a relatively uniform clay layer deposited in the Holocene era. Initially, the effects of both strain and in-situ stress levels on secant shear modulus were carefully examined in cyclic torsion shear tests using undisturbed samples, which were recovered at different depths in a test borehole. The range of shear strain examined was between .001% and 1%. Similar examination was made for a silty clay using reconstituted samples that were isotropically consolidated at different stress levels. On the basis of the results of these laboratory tests, together with the shear modulus from an in-situ seismic survey, the small-strain shear modulus was formulated in terms of the stress and strain levels, and linked also to undrained shear strength. Interactions of the small strain stiffness between in-situ and laboratory are discussed in depth with an attention paid to the existing aging effect in the original subsurface condition.

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The paper presents results from an extensive experimental model study of response of dry sand to impact of a rigid tamper. In the laboratory tests a circular steel tamper was repeatedly dropped on sand contained in a large tank. Measurements included tamper acceleration aud soil pressure at impact, tamper settlement, aud soil densities and strains. Effects of tamper drop height, weight and contact area were investigated. A method is presented for the evaluation of global dynamic stiffness of the soil mass affected by the impact by calculating a dynamic settlement modulus (DSM). The DSM values are determined from integration of the impact acceleration record with respect to time using measured integration constants. DSM values show good correlation to soil densities and corresponding elastic moduli obtained from laboratory tests for loose sand. However, for dense sand, results indicate apparent discrepancies between elastic modulus and the higher DSM values. Analyses of normalized impact energy and the resulting densification in the sand in terms of normalized dimensions of volumetric strain (relative density) contours show unique correlations which are used for a proposed rational design method for dynamic compaction in dry sandy soils.

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Engineering problems concerned either directly or indirectly with unsaturated soils are more and more common, ranging from aspects related to seepage to those related to shear strength and volume change. A few constitutive models have been conceived to describe and quantify these problems all of them with some advantages and drawbacks. Regarding mechanical behavior, the so-called Barcelona Basic Model (BBM) has achieved wide acceptance in geotechnical engineering, basically due to its simple mathematical formulation and good description of phenomena associated with unsaturated soils, especially collapse. Another concept that has emerged as a powerful framework to tackle three-dimensional states in granular materials is that of a modified stress tensor, such as t_ij. In this paper both BBM isotropic structure and t_ij concepts are combined to propose a new elastoplastic model for unsaturated soils, called t_ij-unsat. Modifications and generalizations for unsaturated states are introduced to accommodate those frameworks and overcome some inherited drawbacks. At the end of this work, experimental data gathered from specialized geotechnical literature is used to support the theoretical framework. The satisfactory agreement between simulations and tests results emphasizes the applicability of the proposed formulation to real boundary value geotechnical problems.

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In this study, we have tried to prepare porous ceramics with potato starch as a pore-forming agent at relatively low sintering temperatures by reactive sintering method using fine-grained starting materials. α-Al₂O₃ powder (.1 µm) and TiO₂ rutile powder (2 µm) were wet-ball milled in ethanol for 2 h in a planetary ball-mill. The mixed powder was blended with –30 wt % of potato starch powder in an agate mortar with ethanol. Green samples with no binder were sintered at 1300–1500°C for 2 h in air. The sample contained finer closed pores (<1 µm) as well as the larger pores (– µm). The finer microstructure formation can be explained by (1) the local heating effect via the combustion of potato starch, and (2) water vapor-assisted effect.

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