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  • Joey
    B
    . Tanney, Leonard J. Hutchison
    Mycoscience
    2012年 53 巻 1 号 31-35
    発行日: 2012年
    公開日: 2023/03/31
    ジャーナル オープンアクセス

    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.

  • Suguru TAKATSUTO, Kiyomi KOBAYASHI, Tsuyoshi WATANABE, Hiroki KURIYAMA, Tokuo FURUSE
    Agricultural and Biological Chemistry
    1988年 52 巻 12 号 3217-3218
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • T BAKER, C. RANGACHARYULU
    日本物理学会講演概要集
    1999年 54.2.1 巻 23pSM-6
    発行日: 1999/09/13
    公開日: 2018/03/04
    会議録・要旨集 フリー
  • Keishi Hata, Fuyuki Sugawara, Naganori Ohisa, Saori Takahashi, Kazuyuki Hori
    Biological and Pharmaceutical Bulletin
    2002年 25 巻 8 号 1040-1044
    発行日: 2002年
    公開日: 2002/08/01
    ジャーナル フリー
    We screened the differentiation-inducing activities of 39 mushroom extracts from Akita prefecture, Japan, on the mouse osteoblastic cell line, MC3T3-
    E
    1. Sixteen phosphate buffered saline (PBS), 8 boiled PBS, 14 ethanol and 12 methanol extracts induced alkaline phosphatase (ALP) activities, an indicator of MC3T3-
    E
    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 (
    22E
    ,24R)-ergosta-
    7
    ,
    22
    -diene-3β,
    ,6β-triol (1). 1 induced ALP activities of MC3T3-
    E
    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 MC3T3-
    E
    1 cells by 1, ergosterol (2), ergocalciferol (3), cholesta-3β,
    ,6β-triol (4),
    7
    -dehydrocholesterol (
    5
    ) and cholecalciferol (6) were tested. The enzyme activities of MC3T3-
    E
    1 cells were increased 3.0-fold by 10 μM 1 and 2.4-fold by 10 μM 4. However, 2, 3,
    5
    and 6 did not induce MC3T3-
    E
    1 cell ALP activity at 0.1—10 μM. These results suggested that the OH groups at C-
    5
    and/or C-6 of 1 and 4 played an important role in their differentiation-inducing activities on MC3T3-
    E
    1 cells. Furthermore, 1 suppressed induction of MC3T3-
    E
    1 cell apoptosis by serum starvation.
  • 朱 星華, 津曲 英嗣, 本部 武彦, 池田 剛, 小野 政輝, 野原 稔弘
    天然有機化合物討論会講演要旨集
    2001年 43 巻 57/P-14
    発行日: 2001/09/01
    公開日: 2017/08/18
    会議録・要旨集 フリー
    Our studies on the constituents of so far above forty species of Solanum genera plants have resulted in the isolation of steroidal glycosides potent cytotoxity, antifeedant, anti HSV-1 activities and of the key intermediate on the biosynthesis of solasodine. On the way of these Solanum plants investigation, unusual peculiar steroidal saponins with opened
    E
    -ring type,
    AF
    -1024, which corresponds to the precursor of the spirostanol and furostanol, 16,
    22
    -dicarbonyl type steroids,
    AF
    -a-1 and -2, and a 20-
    22
    -seco-type steroid, SNI-14, have been obtained together with many usual furostanol and spirostanol type glycosides from some Solanum genera, three formers of which were from the fruits of Solanum anguivi, and the latter from the aerial parts of Solanum nigrum, respectively. The structure of
    AF
    -1024 was characterized as 3-O-chacotriosyl 3,16,
    22
    ,26-tetrahydroxycholest-
    5
    -ene 26-O- -
    D
    -glucopyranoside. The configurations at C-16 and -
    22
    were not defined, however, this compound is regarded as an important precursor which would produce furostanol and spirostanol showing a variety of bio-activities.
    AF
    -a-1 and -2 were assumed to be isomers at C-23. The structure of
    AF
    -a-1 was characterized as 3-O- -chacotriosyl (23S,26)-23,26-epoxy-3,26-dihydroxycholest-
    5
    -ene-16,
    22
    -dione. On alkaline treatment, both afforded the identical product. This compound was shown to be 3-O- -chacotriosyl 20-caboxypregna-
    5
    -ene 16-one. The occurrence of
    AF
    -a-1 and -2 are regarded as genuine constituents probably produced directly from
    AF
    -1024 on the biogenetic route. The structure of SNI-14 was characterized as 3-O- -lycotetraosyl 3,16,20(S)-trihydroxy-
    5
    -pregnane 16-O-(
    5
    -O- -
    D
    -glucopyranosyl-4(S)-methyl-
    5
    -hydroxypentanoic acid)-ester. This compound was supposed that it would be produced via furostanol glycoside as if Marker degradation took place in plant body. Representative these unusual novel compounds obtained in this time would provide additional important new pathways, route-A and route-
    B
    , for steroidal biogenesis.
  • Tsuyoshi WATANABE, Hiroki KURIYAMA, Tokuo FURUSE, Kiyomi KOBAYASHI, Suguru TAKATSUTO
    Agricultural and Biological Chemistry
    1988年 52 巻 8 号 2117-2118
    発行日: 1988年
    公開日: 2006/04/05
    ジャーナル フリー
  • Sook Kyoung Kim, Kyoung-Jin Shin, Boyoung Joung, Moon-Hyoung Lee, Hui-Nam Pak
    Journal of Arrhythmia
    2011年 27 巻 Supplement 号 OP42_4
    発行日: 2011年
    公開日: 2012/03/14
    ジャーナル フリー
    Backgrounds: It has been reported that somatic mutations of mitochondrial DNA (mtDNA) is related with aging, or development of cardiovascular disease. We hypothesized that mtDNA4977 deletion mutation (4977-) detected from human blood contributes to atrial dysfunction in patients with
    AF
    . Methods: We studied for mtDNA4977- in 183 patients with non-valvular
    AF
    , (127 PAF, 56 PeAF) and 69 patients with healthy control. The detection of mtDNA4977- was determined by Gene Scan. Results: 1. The mtDNA4977- in
    AF
    patients were older than those without mutation (61.4±
    9
    .2 vs. 51.8±
    9
    .
    9
    , p<0.0001). 2. Frequency of mtDNA4977- mutation in patients with
    AF
    ≤45 years old was not different to age matched control (
    7
    .3% vs. 11.6%, p=0.2371). 3. The mtDNA4977- had higher
    E
    /
    E
    , (11.3±4.8 vs.
    9
    .1±3.1, p=0.0005), plasma levels of TIMP-1 (1.51±0.77 vs. 1.28±0.57 ng/mL, p=0.0210) and ANP (3.11±2.67 vs. 1.91±2.01 nmole/L, p=0.0010), and were more frequently taking statin (27.2% vs.
    22
    .4%, p=0.0055) than those without mutation. 4. 82.3% with mtDNA4977- and
    85
    .
    5
    % without mtDNA4977- remain in sinus rhythm 12.
    7
    ±
    5
    .
    9
    months after RFCA (p=0.3008). Conclusion: mtDNA4977- was related with aging, diastolic dysfunction, serologic markers related with atrial remodeling or pressure overloading. Its frequency was not different to age matched patients with control, and did not affect the clinical outcome after RFCA.
  • 末次 康将
    マリンエンジニアリング
    2021年 56 巻 5 号 680-687
    発行日: 2021/09/01
    公開日: 2021/10/12
    ジャーナル フリー
  • 小田切 孝人, 田代 眞人
    ウイルス
    2013年 63 巻 2 号 233-240
    発行日: 2013/12/25
    公開日: 2014/10/31
    ジャーナル フリー
  • 廣谷 正男, 金子 麻美, 廣谷 聖子, 浅田 善久, 吉川 孝文
    天然有機化合物討論会講演要旨集
    2000年 42 巻 48/P-13
    発行日: 2000/10/01
    公開日: 2017/08/18
    会議録・要旨集 フリー
    Agaricus blazei is an important fungus for producing bioactive compounds. There are some reports of polysaccharides and steroid derivatives from the fruiting bodies of A. blazei. However, the chemical examination of the secondary metabolites of the cultured mycelia of this species has not been reported. Eight compounds, an unprecedented skeleton have been isolated from the cultured mycelia of A. blazei. The structures of the novel compounds each named blazeispirols A (1),
    B
    (2), C (3),
    D
    (4),
    E
    (
    5
    ) X(6), Y (
    7
    ) and Z (8) were confirmed by extensive 1
    D
    and 2
    D
    NMR spectral data and X-ray analysis. Blazeispirols A (1),
    B
    (2), C (3),
    D
    (4) and
    E
    (
    5
    ) were des-A-ergostane type compounds having spiroacetal structure as a side chain. Blazeispirols X (6) and Y (
    7
    ) were determined to be (20S,
    22
    S, 23R, 24S)-1 (10→6) abeo-14β,
    22
    :
    22
    , 25-diepoxyergosta-
    5
    ,
    7
    ,
    9
    ,11-tetraene-3α,23-diol and (20S,
    22
    S, 23R, 24S)-14β,
    22
    :
    22
    ,25-diepoxy-
    9
    ,23-dihydroxyergosta-4,
    7
    ,11-triene-3,6-dione by comparison of extensive 1
    D
    and 2
    D
    NMR spectral data with that of blazeispirol A. The biosynthesis of blazeispirol A was investigated by feeding ^<13>C-labeled acetates and methionine to the growing cultures of A. blazei. The labeling patterns of 1 derived from singly and doubly ^<13>C-labeled acetates were consistent with that of ergosterol reported previously except for the A-ring and then ^<14>C-labeled ergosterol was incorporated into blazeispirol A. Taking the structures of blazeispirols Z and
    D
    into consideration, it can be assumed that blazeispirol A is biosynthesized from ergosterol by the cleavage of C-4, C-
    5
    and C-1, C-10 bonds on retro aldol condensation and Michael reaction via such as intermediate A as shown in Fig. 4. A large number of ergostane-type steroids have been isolated from many fungi. However, blazeispirol A is the first example of a naturally occurring des-A-ergostane-type steroid including a spiroacetal structure moiety as a side chain.
  • Kazuo TAKEUCHI, Masayuki ATSUCHI, Shoji ODA, Minoru JINBO, Takeshi MASUI, Motohide OGASHIWA
    Neurologia medico-chirurgica
    1968年 10 巻 132-133
    発行日: 1968年
    公開日: 2007/08/17
    ジャーナル フリー
  • Özkan ASLANTAŞ, Ebru Şebnem YILMAZ
    Journal of Veterinary Medical Science
    2017年 79 巻 6 号 1024-1030
    発行日: 2017年
    公開日: 2017/06/16
    [早期公開] 公開日: 2017/04/27
    ジャーナル フリー

    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

    E
    . coli isolates were detected in 95 (
    22
    .2%) of the swab samples. Sequencing analysis results showed occurrence of various β-lactamase genes: blaCTX-M-15 (62), blaTEM-
    1b
    (42), blaCMY-2 (
    22
    ), blaCTX-M-3 (16), blaCTX-M-1 (15), blaOXA-1 (
    9
    ) and blaSHV-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.

  • Mitsunobu Ono, Masanobu Shindoh, Masanobu Kobayashi, Fumihiro Higashino, Takao Kohgo, Koichi Yoshida, Yasunori Totsuka
    Oral Medicine & Pathology
    2004年 9 巻 1 号 19-24
    発行日: 2004/03/25
    公開日: 2008/04/01
    ジャーナル フリー
    E
    1
    AF
    , an ets-oncogene family transcription factor, has been shown to upregulate transcription from matrix metalloproteinase (MMP) genes, which confers the invasive phenotype on cancer cells. On the other hand, we have demonstrated by luciferase assay that
    E
    1
    AF
    positively regulates transcription from the p21waf1/cip1 promoter. Ca
    9
    .
    22
    cells were transfected with a metallothionein-inducible
    E
    1
    AF
    expression vector (Ca
    9
    .
    22
    MTF) to investigate the relationship between invasive ability and cell cycle modulation caused by
    E
    1
    AF
    . MMP-
    9
    and p21waf1/cip1 protein were synergistically increased in the ZnCl2 stimulated CA
    9
    .
    22
    MTF cells, and both proteins were identified in the same cells when
    E
    1
    AF
    was induced. These results imply that invasive growth of tumor cells occurs in the static state of the cell cycle and that
    E
    1
    AF
    plays a key role in this phenomenon.
  • Shingo SUMIE, Hiroyuki TAKAMATSU
    Optical Review
    1994年 1 巻 2 号 299-303
    発行日: 1994/12/01
    公開日: 2000/03/28
    ジャーナル フリー
    The effects of the pressure of ambient gas and sample temperature on photo-acoustic displacement (PAD) were studied quantitatively using an extremely sensitive laser interferometric probe. For silicon, the PAD signal measured at atmospheric pressure increased by about 18% as compared to that obtained in a vacuum, and varied by less than 0.
    7
    % for a change in pressure of
    5
    % around 1 atm. This effect was attributed to the decrease in refractive index of the gas adjacent to the sample. Temperature rise caused PAD to increase proportionally, and for GaAs, PAD varied 0.4% per degree. The variation of PAD with temperature was accurately explained by the temperature dependence of thermal expansion coefficient and thermal conductivity of the sample.
  • 藤原 東雄, 上 俊二
    土質工学会論文報告集
    1990年 30 巻 1 号 76-86
    発行日: 1990/03/15
    公開日: 2008/02/29
    ジャーナル フリー
    The behavior of the soft clay grounds subjected to repeated loading is different from that subjected to sustained loading. The difference in settlement between these two loading patterns should be due to secondary compression over a long period of time. Consequently, soft clay grounds subjected to repeated loading tend to be more compressible than those subjected to sustained loading. Therefore, it is necessary for engineers to predict post-construction settlements under repeated loading. In this respect, the preloading is considered to be promising as a countermeasure to reduce the settlement of clay under repeated loading as well as under sustained loading. The effect of preloading on post-construction consolidation settlement of soft clay subjected to repeated loading after removal of a part of preload is investigated in the present paper. It has become clear that the settlement of a clay sample after preconsolidation is mainly affected by the amount of preload, the degree of consolidation due to the preload, the amount of permanent load and the amount of repeated load after removal of preload. The calculated settlement versus time relations using a method to estimate the amount of consolidation settlement of soft clay grounds subjected to repeated loading after removal of preloading were compared with the observed degree of consolidation as parameters of the intensities of preload and repeated load.
  • 小林 優, 神田 扶由子, S. M.
    D
    . Kumar, Ch. V. Lakshmana Rao,
    D
    . Srinivasa Rao,
    D
    . Venkata Rao, C. Bheemasankara Rao
    天然有機化合物討論会講演要旨集
    1990年 32 巻 20
    発行日: 1990/09/25
    公開日: 2017/08/18
    会議録・要旨集 フリー
    Melithasterols A-
    D
    (1-4), isolated from a gorgoinan coral Melithaea ocracea of Okinawa, were shown to be cholestane-, 24-methyl-
    22
    -dehydrocholestane-,
    22
    -dehydrocholestane-, and 24-methylenecholestane-derivatives. respectively, having a common 3β,
    7
    α -dihydroxy-
    5
    α, 6α-epoxy-Δ^8 steroid nucleus. This was confirmed by direct comparison with the authentic sample prepared by lead tetra-acetate oxydation of cholest-6-ene- 3β,
    5
    α, 8α-triol 3-monoacetate. Twelve new polyhydroxysterols were isolated from an Alcyonium sp. (
    7
    ,8,
    9
    ), and Sclerophytum sp. (14,16,19
    b
    ,20,21,
    22
    a,23,26,28) soft corals collected off the coasts of the Andaman and Nicobar Islands in the Indian Ocean. All the Sclerophytum sp. soft corals contained 17a or its 25-deacetyl derivative. Compounds
    7
    to
    9
    were identified as 24-methylenecholest-
    5
    -ene- 3β, 16β-diol-3-0-α-L fucoside (
    7
    ) and its
    7
    β-(8) and
    7
    α-hydroxy (
    9
    ) derivatives. Compound 14 was shown to be 24S-24-methylcholest-
    5
    -ene-3β,25ξ,26-triol and was correlated to the known compound 15 by
    5
    α, 6β-glycolation. Compound 16 was shown to be
    5
    β, 6α-isomer of 17
    b
    , correlating to 17
    b
    by PCC oxidation followed by dehydration. Compound 19
    b
    was identified with 25-deacetyl derivative of the known compound lobosterol (19a) by hydrolysis of authentic lobosterol. Compounds 20 and 21 were shown to be
    7
    -dehydro-(20) and
    22
    E
    -dehydro-(21) derivative of 17a and 17
    b
    , respectively, by comparisons of their spectral data with reference compounds. Compounds
    22
    a and 23 were 24S-methylcholestane-3β,
    5
    α 25-triol-6-one 25-monoacetate (
    22
    a) and its 25-deacetoxyl derivative (23). Partial PCC oxidation of 17a afforded
    22
    a. Compounds 26 (andamansterol) and 28 (nicobarsterol) were shown to be gorgost-
    5
    -ene-3β,
    9
    α. 11α, 21-tetrol and novel secosteroid, 11,21-cyclo-
    B
    -homo-11-oxa-
    9
    , 11-secoergostane-3β, 6α, 12ξ-triol-
    9
    -one, respectively, by spectral analyses (H-HCOSY, HMQC, HMBC).
  • Mitsuhiro Motokawa
    Journal of the Physical Society of Japan
    1978年 45 巻 5 号 1528-1533
    発行日: 1978/11/15
    公開日: 2007/06/01
    ジャーナル 認証あり
    Magnetization and antiferromagnetic resonance studies were done on a single crystal of MnCl2·2H2O at liquid helium temperatures using pulsed magnetic fields up to 180 kOe. The spin-flop phenomenon was observed at 30.2±0.3 kOe under a field along the spin easy
    b
    -axis. Transition from antiferromagnetic to paramagnetic states was observed at 154±2, 142±2 and 152±2 kOe when an external field was applied parallel to the a,
    b
    and c-axes, respectively. Antiferromagnetic resonance absorptions were observed in the frequency range from
    22
    to
    85
    GHz and a zero-field frequency was determined to be
    85
    ±1 GHz. The antiferromagnetic exchange field HE and the orthorhombic anisotropy fields HA1 and HA2 due to the crystalline field constants
    D
    and
    E
    were found to be 71.
    7
    ±1 kOe, 6.0±0.3 kOe, 4.
    5
    ±0.
    5
    kOe, respectively. It was also found that the second easy axis is the a-axis.
  • Zhe Fang, Su Yang Jeong, Hyun Ah Jung, Jae Sue Choi, Byung Sun Min, Mi Hee Woo
    Chemical and Pharmaceutical Bulletin
    2010年 58 巻 9 号 1236-1239
    発行日: 2010/09/01
    公開日: 2010/09/01
    ジャーナル フリー
    Activity-directed isolation of the ethyl acetate, methylene chloride and n-hexane fractions of Gloiopeltis furcata resulted in the isolation of 18 compounds. Their structures were elucidated as 2-(3-hydroxy-
    5
    -oxotetrahydrofuran-3-yl)acetic acid (1), glutaric acid (2), succinic acid (3), nicotinic acid (4), (
    E
    )-4-hydroxyhex-2-enoic acid (
    5
    ), cholesterol (6),
    7
    -hydroxycholesterol (
    7
    ), uridine (8), glycerol (
    9
    ),
    5
    -(hydroxymethyl)-2-methoxybenzene-1,3-diol (10), (
    5E
    ,
    7E
    )-
    9
    -oxodeca-
    5
    ,
    7
    -dienoic acid (11), (Z)-3-ethylidene-4-methylpyrrolidine-2,
    5
    -dione (12), dehydrovomifoliol (13), loliolide (14), cholesteryl stearate (15), palmitic acid (16), cis-
    5
    ,8,11,14,17-eicosapentaenoic acid (17) and α-linolenic acid (18) on the basis of spectroscopic and chemical evidences. Their anticholinesterase and antioxidant activities were evaluated via inhibitory activities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as well as scavenging activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and peroxynitrite (ONOO). All isolated compounds (118) exhibited moderate AChE inhibitory activities with IC50 values ranging from 1.14—12.50 μg/ml, whereas 1,
    7
    ,
    9
    , 17, and 18 showed mild BChE inhibitory activities with IC50 values ranging from
    5
    .57—15.89 μg/ml. Although most of the compounds isolated were lacking the scavenging activity on DPPH radical and ONOO,
    5
    and 10 showed good DPPH radical scavenging activity, and
    5
    , 10, and 16 showed potent ONOO scavenging activity.
  • Yasuyuki Gono, Manabu Fujioka, Tamotsu Toriyama
    Journal of the Physical Society of Japan
    1970年 29 巻 2 号 255-258
    発行日: 1970/08/05
    公開日: 2007/06/01
    ジャーナル 認証あり
    The gamma-ray spectrum and the conversion-electron spectrum are measured in the decay of the Tb152 activity. The L-subshell electron lines of the 586.
    7
    keV
    22
    +→21+ transition are separated by the ion-free beta-ray spectrometer. The M1-
    E
    2 mixing ratio, δ2, and the dimensionless ratio X of
    E
    0-
    E
    2 mixing of the 586.
    7
    keV transition are obtained to be δ2≤0.16 and 0.034≤X≤0.038, respectively. The
    E
    2 branching ratio
    B
    (
    E
    2;
    22
    +→0g+):
    B
    (
    E
    2;
    22
    +→21+):
    B
    (
    E
    2;
    22
    +→01+) is determined to be 0.023 : 1.0 :
    5
    .6.
  • 國生 剛治
    地盤工学会論文報告集
    2000年 40 巻 5 号 99-111
    発行日: 2000/10/15
    公開日: 2008/02/29
    ジャーナル フリー
    In view of the significant role of the water film effect in flow failure for a liquefied sandy deposit, the mechanism of water film generation is numerically studied based on a 1-dimensional model test. The process of water film growth and decay can be simulated to a certain extent by a simple consolidation analysis, which indicates that only a small difference in permeability in layered sand is enough for a water film to develop. A 1 G shaking table test for a two-dimensional slope model with an arc of silt within a saturated sand is then addressed to discuss the dilatancy effect exerted in sheared sand during flow failure. It is possible that, once the water film is formed, the transmission of shear stress through it is interrupted, leaving the sand below free from the dilatancy ; this eventually allows the water film to stay without being absorbed during flow failure. The result of another shaking table test for a trapezoidal slope with horizontal silt seams indicate that water films beneath the seams enable the soil mass above them to laterally flow along water films very gently inclined even after shaking. If a silt seam breaks due to excessive pressure in the water film, it triggers re-liquefaction in the upper sand and leads to further instability.
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