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By merging elasto-plastic finite element analysis with random field theory, an investigation has been performed into the bearing capacity of undrained clays with spatially varying shear strength. The object of the investigation is to determine the extent to which variance and spatial correlation of the soil's undrained shear strength impact on the statistics of the bearing capacity. Throughout this study, bearing capacity results are expressed in terms of the bearing capacity factor, Nc, in relation to the mean undrained strength. For low coefficients of variation of shear strength, the expected value of the bearing capacity factor tends to the Prandtl solution of Nc= 5·14. For higher values of the coefficient of variation, however, the expected value of the bearing capacity factor falls quite steeply. The spatial correlation length is also shown to be an important parameter that cannot be ignored. The results of Monte Carlo simulations on this non-linear problem are presented in the form of histograms, which enable the interpretation to be expressed in a probabilistic context. Results obtained in this study help to explain the well-known requirement that bearing capacity calculations require relatively high factors of safety compared with other branches of geotechnical design.By merging elasto-plastic finite element analysis with random field theory, an investigation has been performed into the bearing capacity of undrained clays with spatially varying shear strength. The object of the investigation is to determine the extent to which variance and spatial correlation of the soil's undrained shear strength impact on the statistics of the bearing capacity. Throughout this study, bearing capacity results are expressed in terms of the bearing capacity factor, Nc, in relation to the mean undrained strength. For low coefficients of variation of shear strength, the expected value of the bearing capacity factor tends to the Prandtl solution of Nc= 5·14. For higher values of the coefficient of variation, however, the expected value of the bearing capacity factor falls quite steeply. The spatial correlation length is also shown to be an important parameter that cannot be ignored. The results of Monte Carlo simulations on this non-linear problem are presented in the form of histograms, which enable the interpretation to be expressed in a probabilistic context. Results obtained in this study help to explain the well-known requirement that bearing capacity calculations require relatively high factors of safety compared with other branches of geotechnical design.

Experimental data on the partitioning of amino acids (tryptophan, phenylalanine) and dipeptides (tryptophan−leucine, phenylalanine−leucine) between the aqueous feed phase and the organic solvent phase are presented. The organic solvent phase consists of a carrier, sodium di-2-ethylhexyl sulfosuccinate/quaternary ammonium salt/dioleyl phosphoric acid, dissolved in (Z)-9-octadecen-1-ol (an organic solvent). The equilibrium distribution coefficient for extractions is determined by varying the following experimental conditions:  feed solution pH, initial feed phase concentration, and composition of organic phase. The partition coefficient for the stripping process is also determined by varying the stripping agent (sodium hydroxide, sodium chloride, sodium carbonate), the concentration, and the pH of the stripping solution. The extraction and stripping reaction coefficients are calculated by combining the experimental data and the kinetic expressions for interfacial reactions. The variation of the values of the coefficients with the solute type (i.e. amino acid or dipeptide) and with the operating conditions of the system di-2-ethylhexyl sulfosuccinate in (Z)-9-octadecen-1-ol is presented.

This paper reports on an investigation into factors affecting planning effectiveness in Hong Kong self-managing schools. Questionnaire survey data from teachers in schools participating in the Phases 1 and 2 of the School Management Initiative scheme in Hong Kong, are analysed. Principal's support and resource support are found to be significant factors in predicting positive outcomes of planning. The concept of flexible planning is explored and conceptualized in terms of built-in flexibility and flexibility through evaluation. An interactive model, `A Self-Managing School Planning Model', which is responsive, recurrent and flexible in nature is proposed.

Basic concepts and methods of random field theory, useful for characterizing 'distributed disordered systems', are applied to a soil deposit to evaluate the spatial extent of liquefaction under typical conditions. The soil deposit, modelled after a site located at the Wildlife Management Area in California, is represented by a three-dimensional random properties field and is subjected to multiple realizations of a space-time random field of earthquake ground motion patterned after the Superstition Hills event of 1987. Based on Monte Carlo analysis using a deterministic one-dimensional nonlinear finite-element program, spatial variability of liquefaction risk is assessed and techniques for improving estimates of liquefaction risk, accounting for local spatial variation, are investigated. Les concepts et m6thodes de base de la théorie de champ aléatoire, servant ´ caracteogonriser les 'systémes désordonnés répartis' sont appliqueogons ´ un d´pôt de sol pour évaluer 1'étendue spatiale de la liquéfaction dans des conditions types. Le dépôt de sol, reproduisant un site situogon dans la Wildlife Management Area en Californie, est représenteacute par un champ de proprieacuteteacutes aleacuteatoires en trois dimensions et soumis a´ de multiples reacuteacutealisations d'un champ aléatoire espacetemps pour les mouvements de terrain seacuteismiques, copieacutes sur Nveacutenement de Superstition Hill en 1987. En nous basant sur une analyse de Monte Carlo utilisant un programme d'éléments finis non linéaires déterministes, nous évaluons la variabiliteacute spatiale du risque de liquéfaction et nous étudions les techniques permettant d'améliorer les évaluations du risque de liqu faction, en tenant compte de la variation spatiale locale.

Twenty-six people with Down's syndrome (DS) were investigated using 99Tcm-hexamethylpropylene amine oxime (99Tcm-HMPAO) and single photon emission tomography (SPET). Dementia was diagnosed using a structured carer interview giving a deterioration score and by studying the case notes. Five subjects were clinically demented, 7 showed mild deterioration and 14 no deterioration. Increased deterioration correlated with advancing age (correlation coefficient 0.5425; P<0.02), but there was no significant difference between older (>40 years) and younger (<40 years) patients. Only one of the subjects with dementia had a regional cerebral blood flow (rCBF) abnormality that was of the dementia of Alzheimer type. Three subjects with mild deterioration and three with no deterioration had abnormal SPET scans. There was no association between the SPET abnormality and clinical dementia or with evidence of deterioration.

Oven drying is the accepted method for determining the dry matter content of kiwifruit (Actinidia deliciosa) and can be used as an indicator of harvest maturity and quality. The disadvantage of this method is the time taken to complete the test, typically overnight. Infrared drying of kiwifruit and apple pomace is shown to be an alternative, giving the same level of accuracy as oven drying but with a much reduced determination time. This method is also comparable in drying time to microwave drying, but with the advantage of continuous recording of drying progress, through to final dry weight.

The synthesis and biological activity of a new series of benzamides and related compounds that upregulate the expression of the low-density lipoprotein (LDL) receptor in human hepatocytes (HepG2 cells) by a novel mechanism are described. The lead compound, N-[5-[(3-cyclohexylpropionyl)amino]-2-methylphenyl]-4-hydroxybenzamide (1, RPR102359), increased the expression of the LDL receptors in HepG2 cells by 80% when tested at a concentration of 3 μM. Mevinolin (lovastatin) was found to increase the LDL receptor expression by 70% at the same concentration. In contrast to mevinolin, 1 was found to have no effect on cholesterol biosynthesis in liver homogenates or in HepG2 cells at doses where substantial upregulation of the LDL receptor was observed and thus stimulated LDL receptor expression by a novel mechanism.

Summary This paper presents the first estimates of three dimensional evolution of activity in the brain associated with a GO/NOGO avoidance (CNV) paradigm. These estimates are continuous probabilistic solutions (Ioannides et al. 1990) to the biomagnetic inverse problem, obtained from averaged multichannel magnetoencephalographic (MEG) recordings (Vieth et al. 1991). The emphasis here is placed on the comparison of the activity associated with the GO and NOGO conditions; estimates of activity are shown for the onset of warning stimulus (S1), the early response half a second after S1, the late response lasting for over one second before S2 (the time between S1 and S2 is 3.5 seconds) and the onset of the imperative stimulus (S2). We find responses in regions of the brain implicated with hearing the stimulus, task engagement and motor output. Differences in the images corresponding to GO and NOGO conditions are significant because they reflect differences in brain function when a motor response is required or must be inhibited.

Clinical, EEG, and biochemical features of 20 patients with narcolepsy and one patient with the Kleine-Levin syndrome are described. The narcoleptic syndrome is a fairly common and life-long disorder which probably results from an inborn error of metabolism, whilst narcolepsy alone is of uncertain diagnostic status. In patients with the narcoleptic syndrome there is a distinctive disorder of night sleep which begins with a period of rapid eye movement and there may be a mistiming in the brain stem mechanisms of sleep, dreaming, and muscle tone. Rapid eye movement periods may not, however, occur during day sleep periods and a normal day-sleep EEG does not exclude this diagnosis. There is no effective and harmless treatment for daytime sleep attacks, but dextro-amphetamine or the less potent levoamphetamine resulted in moderate or good control of narcolepsy in most patients. Clomipramine abolished cataplexy in all and combined treatment for up to two years with amphetamines controlled both narcolepsy and cataplexy in 15 of 17 patients. Side effects of weight gain and reduced libido from clomipramine and bad temper and irritability with insomnia from amphetamines complicated therapy, but the combination did not alter blood pressure. The drugs which improve narcolepsy and cataplexy affect cerebral catecholamine and serotonin metabolism and some aspect of this may therefore be abnormal in patients with the narcoleptic syndrome. In respect of catecholamines, cerebrospinal fluid meanphenylalanine and tyrosine concentrations were normal, whilst homovanillic acid was decreased. However, individual values showed considerable variation. In respect of serotonin, tryptophan and 5-hydroxy-indole-acetic acid concentrations were normal. Cerebrospinal fluid aspartate concentration was low in patients with narcolepsy.

Coupling of the anthranilic acids (I) with the aroyl chlorides (II) leads to the formation of the amides (III) which undergo cyclization in boiling acetic anhydride to form the benzoxazin‐4‐ones (V).

The title compounds (I), obtained by meta photocycloaddition of ethenes to benzenes, undergo acid‐catalyzed cleavage of the cyclopropane ring to give the bicyclo(3.2.1) and/or (3.3.0)octanes (II) and/or (III).