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 () 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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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 possibility of attenuation of microseismic waves due to the presence of an upward folding of the ocean bottom into the liquid is discussed in this paper. The upward folding of the ocean bottom has been idealized by means of an irregularity in the form of a rectangle intruding into the liquid and the evaluation of the displacement component at any point of the solid medium has been carried out in two stages. First, the change in the incident mode of the surface wave due to the presence of the rectangular irregularity has been determined, and second, the subsequent change of the resulting displacement components due to the termination of the liquid layer and the step change in elevation of the solid medium at the continental margin has been discovered. Finally, numerical calculation has been made to determine the attenuation of the microseismic waves of different periods due to the presence of the rectangular irregularity at the ocean bottom.

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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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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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All the birds examined were also associated with bone dysplasia (art alczaormal develop-ment of bone tissue) in the diaphyseal cortex of the leg bones, especially of bones affectedwith dyschondroplasia. This result is very significant in order to clarifyz tlais disease entity.1970:J14, k -1 } 7 ) 7, M77 ) i? ht /, ( K ) 7 (C # L"C, MB @ (7) t, If!TB& U "C, Jff Dyschondroplasia (1*t%7fi!dW) ().g:#[!:.fLlt! K?o, [1: (7)M;tC, rff.?U/:cD, =1lC#li*H(DX15RI!!& t, r, ccl)Efff7flr.#.??t"ut:2.?T<.1.?l??/?t:>"A??1!? > >?TMOll?, lI]%G (-srRM) -ts;;.*BI) *M[t fL 54 t:.;*.{1*I[l?(), t@Yllll*fJ?H@(7) %?Jfipj@ (Dyschondroplasia) p, }, (, 1lTi{-X, WIKIM itt{= t "tl%tff{tO 1111IH(-UP!z U-ii) >ES- -)%Wi*fd?1J*[lEj: >11"iifI".*"H*Tl*&Z") #)/2?-"k l - vich ) J&it(VhiO"= >If-ffi"!1lYl*I")Ji/l![40111!>*!)<Y14M)?A"!>CL(Il], k7.ClT"ltTt*flB1? & $U [-" C U" L % w, Zl1*.IlBl tI1J, FA(y L-x") LVfAK t: >llltPJIiI " } ) t- ! Al j: >kP11liR, &ffl(CNWi Z lk(C#L" Ct ?!M2"C- fL#, -()%.IWMd1.XI1*I1EPW(tit ff1lR)

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Two new polyacetylene compounds (, , 12)-1-acetoxy--isovaleryloxytetradeca-, , 12-trien-, 10-diyn-14-ol (), and (, , 12)-1-acetoxy--(2-methylbutyryloxy)tetradeca-, , 12-trien-, 10-diyn-14-ol (C) have been isolated along with (, , 12)-1-acetoxy--senecioyloxytetradeca-, , 12-trien-, 10-diyn-14-ol (A) from Atractylodes Rhizome (Karabyakujutu). The structures of these compounds were determined on the basis of their spectral data.

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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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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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A boron treated copper bearing HSLA steel containing austenite formers like manganese and nickel, somewhat lower in amount than that in HSLA 100 variety of steel is chosen for the study. The role of thermomechanical processing on the microstructure and mechanical properties of the above steel has been investigated. Differential scanning calorimetric study is carried out for understanding the precipitation behaviour of copper in HSLA steel under the influence of boron. The microstructure of the experimental steel is found to consist of laths of martensites and bainite. MA constituents of ribbon like morphology are observed at the lath boundaries. Higher strength properties of the steel are attributed to the presence of finely distributed precipitates of copper and microalloy carbides.

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This study aimed to determine the prevalence of fecal carriage of extended spectrum β-lactamase (ESBL) and/or plasmidic AmpC β-lactamase (pAmpC) producing Escherichia coli among dogs (n=428) in Turkey. Polymerase chain reaction (PCR) and sequencing were used to characterize genes encoding β-lactamase and plasmid mediated quinolone resistance (PMQR). Antimicrobial susceptibility testing and PCRs for virulence genes and phylogenetic groups were also performed. Cefotaxime resistant

. coli isolates were detected in 95 (.2%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: bla_CTX-M-15 (62), blaTEM-

1b

(42), bla_CMY-2 (

22

), blaCTX-M-

3

(16), bla_CTX-M-1 (15), bla_OXA-1 (

9

) and bla_SHV-12 (

3

) alone or in combination. The most frequently encountered phylogenetic group was group A₁ (35.

8

%), followed by group

D₂

(

22

.1%),

B

1 (15.

8

%),

D₁

(

9

.

5

%),

A₀

(7.

4

%),

B2₂

(

5

.

3

%) and

B2₃

(

4

.2%), respectively. PMQR genes, aac(

6

’)-Ib-cr, qnrS1 and qnrB10 were detected in 25.

3

, 10.

5

and 1.1% of the isolates, respectively. While all isolates were susceptible to imipenem and amikacin, resistance rates to non-β-lactam antibiotics ranged from 20.

0

% for tobramycin to 56.

8

% for tetracycline. The virulence genes were only detected in 34 (36.2%) of the isolates and this isolates carried single or various combination of virulence genes of iucD, papC, papE,

f17a

-A and eaeA. Four isolates were identified as human virulent pandemic CTX-M-15 producing

E

. coli clone O25

b

:ST131/

B

2. To the best of our knowledge, this is the first study to show fecal carriage of ESBL/pAmpC type β-lactamase producing

E

. coli isolates among dogs in Turkey.

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By employing an undrained cyclic loading ring-shear apparatus, a series of tests to reproduce the dynamic behavior of the Nikawa landslide induced by the January 17, 1995 Hyogoken-Nambu earthquake, is conducted. The test sample is Osaka-group coarse sandy soil taken from the landslide. The initial stress condition acting on a soil element in the sliding surface is applied to the sample. Based on the seismic records monitored at the JR Takarazuka Station, the input seismic wave is synthesized to reproduce the seismic stress acting on the sliding surface. The test results show that the soil failed due to the dynamic loading of the earthquake. The most important results are the excess pore water pressure generation and the acceleration of shear displacement continuing after the main shock. Combined with the grain crushing at the shear zone and the volume reduction in the drained constant-speed ring-shear test, the mechanism of this landslide is interpreted as, shear displacement causing grain crushing in the shear zone and volume reduction, and then resulting in a localized liquefaction phenomenon, "sliding-surface liquefaction". This geotechnical simulation test provides a reasonable interpretation of this highly mobile landslide.

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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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