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–

,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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One method currently being considered for the disposal of high level radio-active waste is burial in the seabed. When a hot object is buried in soil, the temperature of the soil adjacent to the object is raised and there is transient heat flow away from the object. The rise in the temperature of the soil causes excess pore pressures to be generated and transient pore water diffusion also takes place. A finite element formulation of the coupled heat flow and consolidation problem is presented. The computer implementation of this formulation is found to compare favourably with analytical solutions based on the same physical principles.

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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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Two new partially saturated tricyclic ring systems, 6, 6a, , , , 10, 10a, 11-octahydro-11-oxodibenz [, ] oxepins (3a and 3), and -thiepins (4a and 4) were synthesized. Compounds 4a and 4 were desulfurized to give a pair of isomeric 2-methylbenzoylcyclohexanes (10a and 10). Deuterated 4a and 4 (11a and 11) were prepared starting from butadiene-d₆ (12). The stereochemical features of 3a (trans), 3 (cis), 4a (trans) and 4 (cis) are compared with those of 10a, 10, 11a and 11 on the basis of proton nuclear magnetic resonance data.

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The phase diagrams of the Ni-Mo- and Ni-W- ternary systems in the region of less than 50mol% were constructed by thermodynamic calculation, based on the data obtained by thermodynamic measurement of the related materials. We found three ternary eutectic points and three or two ternary peritecto-eutectic points as follows:
:L (1365K, 71.mol%Ni-6.0mol%Mo-.mol%)=(Ni)++
:L (1355K, 62.mol%Ni-2.mol%Mo-30.mol%)=++
:L (1445K, 42.0mol%Ni-30.6mol%Mo-10.3mol%)=(Ni)+NiMo+
:L (1812K, 34.mol%Ni-42.3mol%Mo-.mol%)+MoB=+
P₂:L (1633K, 42.3mol%Ni-40.4mol%Mo-17.3mol%)+Mo=+
P₃:L (1812K, 53.mol%Ni-33.mol%Mo-12.mol%)+Mo=NiMo+
:L (1622K, 51.0mol%Ni-31.6mol%W-17.4mol%)=(Ni)+W+
:L (1260K, 71.0mol%Ni-.0mol%W-.0mol%)=(Ni)++
:L (1291K, 65.4mol%Ni-4.mol%W-29.mol%)=++
:L (2115K, 23.mol%Ni-43.mol%W-33.mol%)+WB=+
P₂:L (1657K, 48.mol%Ni-33.mol%W-18.0mol%)+=W+
The calculated phase diagrams are expected to be useful for the development of new Ni-based heat-, corrosion- or wear-resistance alloys.

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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

), bla_CTX-M-3 (16), blaCTX-M-

1

(15), blaOXA-

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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11-Amino-6, 6a, , , , 10, 10a, 11-octahydrodibebenzo[, ]thiepines (6a-d) and -oxepines (a-d) were synthesized by the Leuckart reaction of 6, 6a, , , , 10, 10a, 11-octahydro-11-oxodibenzo[, ]thiepines (a, )and -oxepines (2a, ) followed by hydrolysis of the reaction products 4a-d and a-d, respectively. The four diastereomers, cis(6a-H, 10a-H)-cis(10a-H, 11-H) 6a and a, cis(6a-H, 10a-H)-trans(10a-H, 11-H) 6 and , trans(6a-H, 10a-H)-trans(10a-H, 11a-H)6c and c, and trans(6a-H, 10a-H)-cis(10a-H, 11-H) 6d and d, were isolated and their configurations and conformations were elucidated by chemical methods together with

1H

-nuclear magnetic resonance spectroscopic and X-ray crystallographic analyses.

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Pironetin (PA-48153C) is a novel unsaturated δ-lactone derivative isolated from the fermentation broths of Streptomyces species which shows immunosuppressive and plant growth regulating activities. Several total syntheses of have been reported to date, but we show here a novel approach to via a convergent route using our chiral building block, (S,S,6R)--hydroxybicyclo[4..0]heptan-2-one . We dissected pironetin at C6-C and employed the coupling of the epoxide 16 with the dithiane 25, which would be derived from , as a key step. The THP ether of was methylated and the following reduction gave an inseparable mixture of four diastereomers . After etherification, removal of THP group afforded separable isomers a and in a ratio of 13 to . The desired major isomer a was oxidized to ketone 6. Oxidation of 6 via silyl enol ether with osmium tetroxide gave ketol 21 in quantitative yield. Reduction of cyclopropylketone moiety of 21 under Birch condition afforded a mixture of a and . The ketol moiety of a and was oxidatively cleaved with lead tetraacetate in benzene-methanol to give the single aldo-ester 23. Acetalization of 23 followed by reduction of ester group gave aldehyde 24. Introduction of C2-unit via Takai's protocol as -olefin formation followed by thioacetalization afforded the dithiane 25, as C-C14 unit of pironetin. Meanwhile, the epoxide 16 as C-C6 unit was prepared from known epoxy alcohol 3 in 6 steps. Coupling reaction of two units, the dithiane 25 and the the epoxide 16, successfully gave the product with the whole skeleton 26 in high yield. Mercuric ion assisted hydrolysis of the thioacetal 26 gave ketol 27. Selective reduction of β-hydroxyketone 27 by Mori's method afforded and-diol 28a predominantly (: ). Finally, desilylation and oxidation with manganese dioxide afforded pironetin .

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Melithasterols A-D (-4), isolated from a gorgoinan coral Melithaea ocracea of Okinawa, were shown to be cholestane-, 24-methyl--dehydrocholestane-, -dehydrocholestane-, and 24-methylenecholestane-derivatives. respectively, having a common 3β, α -dihydroxy-α, 6α-epoxy-Δ^ steroid nucleus. This was confirmed by direct comparison with the authentic sample prepared by lead tetra-acetate oxydation of cholest-6-ene- 3β, α, α-triol 3-monoacetate. Twelve new polyhydroxysterols were isolated from an Alcyonium sp. (,,), and Sclerophytum sp. (14,16,19,20,21,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 to were identified as 24-methylenecholest--ene- 3β, 16β-diol-3-0-α-L fucoside () and its β-() and α-hydroxy () derivatives. Compound 14 was shown to be 24S-24-methylcholest--ene-3β,25ξ,26-triol and was correlated to the known compound 15 by α, 6β-glycolation. Compound 16 was shown to be β, 6α-isomer of 17, correlating to 17 by PCC oxidation followed by dehydration. Compound 19 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 -dehydro-(20) and -dehydro-(21) derivative of 17a and 17, respectively, by comparisons of their spectral data with reference compounds. Compounds a and 23 were 24S-methylcholestane-3β, α 25-triol-6-one 25-monoacetate (a) and its 25-deacetoxyl derivative (23). Partial PCC oxidation of 17a afforded a. Compounds 26 (andamansterol) and 28 (nicobarsterol) were shown to be gorgost--ene-3β, α. 11α, 21-tetrol and novel secosteroid, 11,21-cyclo--homo-11-oxa-, 11-secoergostane-3β, 6α, 12ξ-triol--one, respectively, by spectral analyses (H-HCOSY, HMQC, HMBC).

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The effect of composition and controlled thermomechanical process parameters on the mechanical properties of HSLA steels is modelled using the Widrow-Hoff's concept of training a neural net with feed-forward topology by applying Rumelhart's back propagation type algorithm for supervised learning, using a Petri like net structure. The data used are from laboratory experiments as well as from the published literature. The results from the neural network are found to be consistent and in good agreement with the experimented results.

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Horizontal plate anchors are widely used in civil engineering constructions to resist vertical pulling loads. The available theoretical model suggested by Vesic to estimate the breakout resistance of plate anchors is in significant error, particularly for dense sandy soils. A theoretical model assuming a curved surface of failure through the surrounding soil, to evaluate the ultimate breakout resistance of horizontal plate anchors, has been proposed. It successfully brings out the concept of characteristics relative depth beyond which the breakout factor reaches a constant final value. It is capable of predicting breakout factors for wide range of values of angle of shearing resistance of sand.

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An unsupervised learning technique and an associative memory have been used for encoding weights by a special type of Petri network named Petri neural net for modelling the influence of alloying elements on the final property of the high strength low alloy steel. The combined effects of alloying elements for different strengthening mechanisms is predicted when weights and threshold values are chosen on the basis of metallurgical understanding. The technique is found to be effective to create an associative memory of input-output relations in unknown data sets so that the same can be subsequently be used as a predictive tool.

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Primarily from the point of view of improvement of yield strength due to additions of niobium, titanium and boron in HSLA steels, the experimental steels are divided into five classes. The data are then supplied for learning a Self Organising Map (Kohonen network). It is found that the network with six neurons possesses better capacity of prediction with unknown data. Another effort of clustering the steels according to its major strength contributing mechanisms is also made. But the capacity of the network to cluster unknown data is found to be rather poor and has failed to follow from the metallurgical principles. To avoid this limitation, Learning Vector Quantisation method is adopted to impart a certain amount of supervision in the learning process and it is found that the training pattern of the network attains a good convergence thereby leading to a good predictive ability.

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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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2-Benzyl-4-chloro--mercapto-3 (2H)-pyridazinone () was heated in ethanol under reflux for 10 hours to form concurrently 2, -dibenzyldipyridazo [4, - : 4', '-]-, 4-dithiin-, 6 (2H, H)-dione (Ia) (57% in yield) and 2, -dibenzyldipyridazo [4, - : 4', '-]-, 4-dithiin-, (2H, H)-dione (IIa) (14% in yield). Assignment of the two products to the corresponding structures is established by their physico-chemical constants and chemical behaviors. The concurrent formation of the dipyridazo [4, - : 4', '-]-, 4-dithiin-, 6 (2H, H)-dione and the -, (2H, H)-dione were observed in, not only heating 4-chloro--mercapto-3 (2H)-pyridazinones (-3) in polar solvent, but warming 4-mercapto--chloro-3 (2H)-pyridazinones (4-6) in the presence of potassium carbonate in DMF. For the interpretation of the reaction, keto-thioketo carbenes as active intermediate species and a reversible interconversion among them are suggested on the basis of the fact that there was nonexistence of an equilibrium between the two compounds, such as Ia and IIa, under the reaction condition and a trapping keto-thioketo carbene species as 2-phenylimino--benzylpyridazo [4, -d]-, 3-dithiol-4 (H)-one (IVa) (14% in yield) along with the major products, (Ia) and (IIa), was furnished by warming with phenylisothiocyanate in the presence of triethylamine in dry benzene. On the contrary, participation of a reversible interconversion between Ia and IIa, to a considerable extent, with the concurrent formation of them in the case of benzylation of either Ib or IIb, by warming with benzylchloride in the presence of potassium carbonate in DMF at 80°, might not be neglected, because an attempted approach to an equilibrium between Ia and IIa in a similar reaction condition except the use of benzylchloride realized, whereas non-existence of an equilibrium between Ib and IIb in the similar reaction condition was observed.

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Brassinolide analogues, (R, 23R, 24R)-2α, 3α, , 23-tetrahydroxy--homo--oxa--ergostan-6-one (24-epibrassinolide) (10) and (S, 23S, 24R)-2α, 3α, , 23-tetrahydroxy--homo--oxa--ergostan-6-one (), were synthesized from brassicasterol (3a) in five steps and with ca. 20% overall yield. The key steps are the direct formation of (, 24R)-3α, -cyclo--ergost--en-6-one (4) from brassicasterol mesylate (3), the acid-catalyzed rearrangement of 4 to (, 24R)--ergosta-2, -dien-6-one (6), and the Baeyer-Villiger oxidation of the tetrahydroxy -ergostan-6-ones and .

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