Static characteristics of two different structured InAlGaAs/InAlAs superlattice avalanche photodiodes (SLAPDs) cooled by liquid nitrogen were evaluated at a wavelength of 1. μm. The dark current of the SLAPD having a thick superlattice layer of 0.504 μm was ×10^-13 A. This was successively reduced by four orders of magnitude compared to that of the thin layer SLAPD of 0.231 μm at a breakdown voltage of around 20 V. The thickened layer was effective in suppressing tunneling dark current. An output current of 1.7×10^-12 A at a bias voltage of 15 V was measured for an optical input with a wavelength of 1. μm and a signal power of 1×10^-12 W. This showed a sharp distinction from the dark current.

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS 7th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a 7th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -dB frequency bandwidth, group delay ripple, rd-order distortion, and rd-order input intercept point (IIP) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.dBm, respectively, all with a ±0.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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A biosynthetic pathway for (

)-methyl cinnamate formation was evaluated in Tricholoma matsutake by tracer experiments using

13C

- and ²H-labeled precursors. One hundred percent selective

13C

incorporation was observed when L-[1,2,

3

,4,

5

,

6

,7,

8

,

9

-

13C₉

, ^15/N]phenylalanine was converted to (

E

)-[1,2,

3

,4,

5

,

6

,7,

8

,

9

-

13C₉

]cinnamate and (

E

)-[1,2,

3

,4,

5

,

6

,7,

8

,

9

-

13C₉

]methyl cinnamate. Similarly, 100% selective

13C

incorporation was observed when (

E

)-[1,2,

3

,4,

5

,

6

,7,

8

,

9

-

13C₉

]cinnamate was converted to (

E

)-[1,2,

3

,4,

5

,

6

,7,

8

,

9

-

13C₉

]methyl cinnamate. In contrast, the ²H incorporation selectivities were

82

.1% and

81

.4% when L-[2,

3

,4,

5

,

6

,7,7,

8

-

2H₈

]phenylalanine was converted to (

E

)-[2,

3

,4,

5

,

6

,7,

8

-²H₇]cinnamate and (

E

)-[2,

3

,4,

5

,

6

,7,

8

-²H₇]methyl cinnamate, respectively. Thus, T. matsutake synthesizes (

E

)-methyl cinnamate from L-phenylalanine via (

E

)-cinnamate. (

E

)-cinnamate was likely formed through two pathways: one was major and the other was a minor.

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1. The chromosome numbers of 64 species have been studied on which 56 are investigated for the first time.
2. Morphological, anatomical and cytological findings on the Musaceae in the broad sense are considered from a phylogenetical standpoint and three distinct groups:
a) Musa-Ensete, b) Ravenala-Strelitzia-Phenakospermum and ) Holiconia are recognised as suggested by some authors. For these groups sub-familial status is proposed.
. Lowiaceae have been studied for the first time cytologically and their chromosome morphology, distinct from that of any other group of Zingiberales, confirms their claim to familial status.
4. Consideration of the conflicting theories proposed to account for the higher chromosome number in genera like Globba, Alpinia, and Phaemeria, etc. leads to rejection of Chakravorti's hypothesis of wholesale fragmentation of chromosomes and the acceptance of the opposed view of Raghavan and Venkatasubban and others.
. Holttum's transference of the genus Zingiber to the tribe Hedychieae has been given cytological support on the following points:
a) the basic number in the genus Zingiber correlates with that of Kaempferia.
b) the new tribe Alpinieae (which is infact Zingibereae without Zingiber) have consistently 48 chromosomes in their somatic complements.
. It is suggested that the African representatives of Kaempferia should be given the status of genus; Cienkowskya on the following points:
a) the difference in floral morphology
b) geographical separateness and
) the difference in the number and morphology of the chromosomes. By comparing the present and past findings, various lines of evolution of the chromosome complements within each group are discussed.
7. The basic number 11 is considered to be probably the original one for the Zingiberales as a whole, being present in Ravenala which is the most primitive member in the order. From this secondary basic numbers have arisen through evolution.

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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 () 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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We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MCT-1. Sixteen phosphate buffered saline (PBS), boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MCT-1 cell differentiation. The enzyme activities were markedly induced by extracts of Tricholoma auratum, and we isolated the active compound from methanol extracts of this mushroom. Physical data for the isolated active compound were identical to those for (,24R)-ergosta-7,-diene-,,-triol (1). 1 induced ALP activities of MCT-1 cells and promoted cell proliferation. To investigate the relationships between the chemical structure and differentiation-inducing activity of the compound, ALP-inducing activities of MCT-1 cells by 1, ergosterol (2), ergocalciferol (), cholesta-,,-triol (4), 7-dehydrocholesterol () and cholecalciferol () were tested. The enzyme activities of MCT-1 cells were increased .0-fold by 10 μM 1 and 2.4-fold by 10 μM 4. However, 2, , and did not induce MCT-1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at - and/or - of 1 and 4 played an important role in their differentiation-inducing activities on MCT-1 cells. Furthermore, 1 suppressed induction of MCT-1 cell apoptosis by serum starvation.

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The activities of tobramycin derivatives acetylated and ethylated on the '-N, 2'-N and -N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and '-N-ethylated derivatives have a fairly good activity, and confirmed that the -N position is the most important one for antibiotic activity since -N derivatives were less active. The MICs of these derivatives against tobramycin resistant strains, and their inactivation by tobramycin modifying enzymes were examined. These results showed that 2'-N or '-N ethylation protects the drug against inactivation by AAC(2') or AAC('), respectively, and 2'-N-ethyltobramycin and '-N-ethyltobramycin were active against strains containing these modifying enzymes. On the other hand, -N ethylation protects the drug against inactivation by AAC() but -N-ethyl tobramycin does not inhibit strains containing this enzyme.

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Two new polyacetylene compounds (4, , 12)-1-acetoxy--isovaleryloxytetradeca-4, , 12-trien-, 10-diyn-14-ol (B), and (4, , 12)-1-acetoxy--(2-methylbutyryloxy)tetradeca-4, , 12-trien-, 10-diyn-14-ol () have been isolated along with (4, , 12)-1-acetoxy--senecioyloxytetradeca-4, , 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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The correction factor (η_ie) for the ultimate bearing capacity of a footing placed adjacent to a slope, taking into account the combined effect of horizontal and vertical seismic loads, represented by horizontal and vertical seismic coefficients, k_h and k_v, respectively, was derived using a modified Janbu's slice method. The influence of slope angles ‘α’ on the values of ‘η_ie’ are studied here. It was found that the values of η_ie can be expressed as an exponential function of ‘k_h/(1-k_v)’ and ‘α’, with a measurable interdependency between ‘α’ and ‘η_ie’. The influence of ‘α’ on the value of ‘η_ie’ increases as the input value of ‘k_h/(1-k_v)’ increases. Equations derived based on the analytical results are proposed to account for this effect. Based on the analyses of 11 near-fault seismographers obtained in the 1999 Chi-Chi earthquake in Taiwan, a ratio between the vertical and the horizontal seismic coefficients, λ, of between ±0.25 is suggested for including the combined effect of vertical and horizontal seismic forces in evaluating the seismic bearing capacity of footings located in near-fault areas.

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At present, analytical or empirical formula for seismic bearing capacity of footings adjacent to slopes is not available. This study uses a pseudo-static-based approach in conjunction with rigorous Janbu's slice method to derive analytical values of seismic bearing capacity factors (N_γ) and correction factors for the effects of inertia of soil mass and load inclinations for a rigid footing adjacent to cohesionless slopes. It is shown that both the bearing capacity factors (N_γ) and the correction factors for the seismic bearing capacity of footings placed on level ground derived herein are comparable with those reported in the literature. Empirical equations regarding the effects of slope angles and load inclinations, expressed using generalized forms of those proposed in the literature, are also derived. It is also found that the empirical equations derived in the present study provide values of correction factors in good agreements with the analytical ones, indicating the validity of using these empirical equations for assessing the bearing capacity of rigid footings situated on the slope subjected to pseudo-static seismic loading.

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This paper is concerned with dynamics of the standard penetration test (SPT). The usefulness of mounting strain gages at two different stations along a driven rod is described, together with a workable procedure of analysis. The analysis procedure makes use of the traveling time between the two gage points and enables one to identify the particle velocity, the displacement and the stress at any station of the rod, as well as the energy actually transmitted from a hammer to the rod. Particular attention is called for the consequence of inevitable, small errors in strain data upon such identifications. A pertinent procedure of error-correction is proposed and its validity is substantiated against the performance of well instrumented SPTs performed by the authors.

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(

3H

) Tobramycin was used as a probe to determine the relationship between the structure of aminoglycoside antibiotics and their ability to remove this drug from its higher affinity binding site on the ribosome. The dissacharide moieties (neamine, tobramine, gentamine) appeared to have a common binding site, whereas the kanosamine, garosamine and ribose moieties determined the specificity of this binding. Amikacin and butikacin behaved in an anomalous manner in spite of their close structural relationship to tobramycin.

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L'entree en Iran des armees britannique et sovietique s'est produite en aout 1941. Elle ebranla du coup le regime de la dynastie pahlavi qui etait au pouvoir depuis 16 ans, et mena le pays vers l'instabilite politique et le chaos social. La defaite de l'arme gouvernementale, qui etait le pivot du regime de Reza Shah, reduisit considerablement le controle du gouvernement central dans le pays. Cette situation politico-sociale confuse permit le developpement de differents mouvements politiques en Iran. ainsi que le 16 aout 1942 le parti clandestin Komeley Jiyanewey Kurdistan (J-K) est ne a Mehabad, une ville au nord-ouest de l' Iran. Des sa formation, ce parti a su etendre sa sphere d'activite et, en une courte periode de temps, a fini par mettre sous son influence la ville et ses alentours. A la fin de la Seconde Guerre mondiale, en ete 1945, le J-K etait devenu une organisation representant le mouvement nationaliste kurde en Iran. a ce moment-la qu'un autre parti politique, le Hizbi Dimokratiki Kurdistan (HDK), fonde par Qazi Mihemed a Mehabad aussi, devait remplacer le J-K. Des le janvier 1946, le HDK proclama l'instauration de la≪Republique de Kurdistan≫. Cependant, les troupes sovietiques qui avaient pris sous leur protection la Republique evacuerent les terres iraniennes, en mai 1946. Six mois plus tard, sous la pression militaire du gouvernement central iranien, la republique s'ecroula. Deux theories tentent d'expliquer le passage du J-K au HDK. William Eagleton Jr., par exemple, affirme dans The Kurdish Republic of 1946 que le HDK a ete cree sur le conseil des autorites sovietiques. L'ex-secretaire general du Parti Democratique du Kurdistan d'Iran, 'Ebd el-Rehman Qasimlu maintient par contre que Qazi Mihemed a etabli le nouveau parti de sa propre initiative, eu regard a la situation politique de cette epoque-la. Il considere que la passage du J-K au HDK comme etant l'evolution d'un parti nationaliste clandestin en un parti democratique. En analysant ces deux theories et en se basant sur les autobiographies des personages qui se sont engages dans cet evenement, cette etude tentera d'examiner le principe directeur et les activites du J-K et de mieux comprendre les raisons pour lesquelles le J-K devait etre remplace par le HDK. La conclusion generale portera sur les differents objectifs politiques du J-K et du HDK. Le J-K visait l'elevation du niveau culturel du peuple tout en luttant contre le tribalisme, qui etait, selon lui, le probleme majeur de≪la nation kurde≫, et cela en ecartant toute idee de revolte militaire. Le J-K a aussi exclu de son cadre les elites sociales telles que les leaders des tribus et dirigeants religieux de peur qu'ils n'excercent une influence sur les membres du parti. L'automne de 1944 fut le debut d'une nouvelle ere pour le mouvement kurde. Alors que l'espoir de l'autodetermination augmentait parmi le peuple a mesure que s'approchait la fin de la guerre, la necessite de la force militaire a commence a se faire sentir dans le J-K. pour cela que s'est produite au sein du parti une tendance a compter sur l'aide militaire des sovietiques et a recourir au leadership de Qazi Mihemed, qui avait une certaine influence meme sur les leaders tribaux. Mais cette tendance etait essentiellement incompatible avec la ligne fondamentale du J-K et, graduellement, a prive ce parti de sa raison d'etre. Ainsi, le HDK se substitua au J-K en tant que≪parti democratique≫visant a rallier d'abord les elites sociales sous sa banniere, en s'appuyant sur l'autorite personnelle de Qazi Mihemed.

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