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Li-insertion-induced phase transformation in nanoscale olivine particles is studied by phase-field simulations in this paper. We show that the anisotropic growth morphology observed in experiments is thermodynamically controlled by the elastic energy arising from the misfit strain between the Li-rich and Li-poor olivine phases and kinetically influenced by the Li surface-reaction kinetics. The one-dimensional Li diffusivity inherent to the olivine structure is found to kinetically stabilize the phase boundary morphology after Li insertion termintates and facilitate ex-situ observation. Our calculations suggest that examination of the phase boundary morphology provides an effective approach to determine the limiting process of the Li intercalation kinetics in olivine nanoparticles.

This paper describes a numerical method for the solution of plasma fluid equations on block-structured, locally refined grids. The plasmas under consideration are typical of those used for the processing of semiconductors. The governing equations consist of a drift–diffusion model of the electrons, together with an energy equation, coupled via Poisson's equation to a system of Euler equations for each ion species augmented with electric field, collisional, and source/sink terms. A discretization previously developed for a uniform spatial grid is generalized to enable local grid refinement. This extension involves the time integration of the discrete system on a hierarchy of levels, each of which represents a degree of refinement, together with synchronization steps to ensure consistency across levels. This approach represents an advancement of methodologies developed for neutral flows using block-structured adaptive mesh refinement (AMR) to include the significant additional effect of the electrostatic forces that couple the ion and electron fluid components. Numerical results that assess the accuracy and efficiency of the method and illustrate the importance of using adequate resolution are also presented.

The effects of prokinetic treatment with cisapride in patients with constipation-predominant irritable bowel syndrome (IBS) were evaluated in a randomized, doublelind, placebo-controlled study. Sixty-nine IBS patients were assigned to a 12-week treatment with either 5 mg cisapride or placebo t.i.d.; this dosage could be changed of necessary. The mean weekly number of days on which stool was passed in the cisapride and placebo group ncreased to 5.3 and 4.4 (p < 0.05) during weeks 8–12 of reatment, and the number of days with stools of normal consistency increased to 3.5 and 1.9 (p < 0.05), respectively. At week 12, the reduction in severity and frequency scores for abdominal pain was significantly reater (p ≤ 0.05) in the cisapride group (60 and 61) than in the placebo group (40 and 32), as it was for abdominal listension (p < 0.05). Cisapride tended to be better than placebo in diminishing flatulence. In 71 versus 39 of he patients the overall rating for the response to treatment was good or excellent at week 12. Cisapride was well tolerated. These results suggest that the drug will be useful for the management of constipation-predominant BS.

Test excavations conducted at Drotsky’s Cave have provided important new information on the paleoenvironment and archaeology of the western Kalahari desert during the late and terminal Pleistocene. An occupation layer dated to the terminal Pleistocene was rich in Late Stone Age artefacts, pieces of ostrich egg shell, the remains of carnivorous bullfrogs, springhare, and other fauna. A detailed sediment study, along with the evidence of Angoni vlei rat, climbing mouse, an aquaticXenopusfrog, and side neck turtle confirms that conditions were for the most part, substantially more moist than at present between approximately 30,000 and 11,000 years ago. Analysis of a diatom assemblage dated to the terminal Pleistocene implies that the currently dry Gcwihaba Valley was most likely flowing for much of the year. Our evidence supports findings made at other localities in the Kalahari documenting the existence of especially moist conditions during the terminal Pleistocene.

This paper describes a numerical method for the solution of a system of plasma fluid equations. The fluid model is similar to those employed in the simulation of high-density, low-pressure plasmas used in semiconductor processing. The governing equations consist of a drift-diffusion model of the electrons, together with an internal energy equation, coupled via Poisson's equation to a system of Euler equations for each ion species augmented with electrostatic force, collisional, and source/sink terms. The time integration of the full system is performed using an operator splitting that conserves space charge and avoids dielectric relaxation timestep restrictions. The integration of the individual ion species and electrons within the time-split advancement is achieved using a second-order Godunov discretization of the hyperbolic terms, modified to account for the significant role of the electric field in the propagation of acoustic waves, combined with a backward Euler discretization of the parabolic terms. Discrete boundary conditions are employed to accommodate the plasma sheath boundary layer on underresolved grids. The algorithm is described for the case of a single Cartesian grid as the first step toward an implementation on a locally refined grid hierarchy in which the method presented here may be applied on each refinement level.

Copolymer 1 (Cop 1) is a synthetic basic random copolymer of amino acids that has been shown to be effective in suppression of experimental allergic encephalomyelitis and has been proposed as a candidate drug for multiple sclerosis. Cop 1 is immunologically cross reactive with myelin basic protein (BP) and was shown to inhibit murine BP-specific T-cell lines of various H-2 restrictions. In the present study these findings were extended to include human T-cell lines. Cop 1 competitively inhibited the proliferative responses and interleukin 2 secretion of six BP-specific T-cell lines and 13 clones with several DR restrictions and epitope specificities. Conversely, BP inhibited--albeit to a lesser extent--the response of all the Cop 1-specific T-cell lines and clones, irrespective of their DR restrictions. Another random copolymer of tyrosine, glutamic acid, and alanine, denoted TGA, had no effect on these lines. Neither Cop 1 nor BP inhibited the response of lines and clones specific for purified protein derivative. Cop 1 and BP exerted their cross-inhibitory effects only in the presence of antigen-presenting cells. These results suggest that Cop 1 can compete with BP for the binding to human major histocompatibility complex molecules. In view of recent studies implicating BP reactivity in multiple sclerosis, these findings suggest a possible mechanism for the beneficial effect of Cop 1 in this disease.

Summary Since the CT has become the main diagnostic tool in head trauma, more cases of DEDH have become confirmed and published although some have been classified among other entities and under different criteria.

SummaryAn evaluation was carried out of the effect of domperidone on gastro-intestinal symptoms in patients with irritable bowel syndrome. Ninety-eight patients were included; 32 in an open pilot study and 66 in a double-blind placebo-controlled study. Domperidone was taken at a dosage of 10 mg tablets 4-times daily. At the end of the 4-week treatment, symptoms had disappeared or were at least markedly improved in about 80 % of the domperidone-treated patients. Significant superiority of domperidone to the placebo was observed for the symptom clusters ‘post-prandial flatulence’, ‘abdominal pain’ and ‘abnormal bowel habit’. No side-effects were reported.

Summary In theh-version of the finite element method, convergence is achieved by refining the mesh while keeping the degree of the elements fixed. On the other hand, thep-version keeps the mesh fixed and increases the degree of the elements. In this paper, we prove estimates showing the simultaneous dependence of the order of approximation on both the element degrees and the mesh. In addition, it is shown that a proper design of the mesh and distribution of element degrees lead to a better than polynomial rate of convergence with respect to the number of degrees of freedom, even in the presence of corner singularities. Numerical results comparing theh-version,p-version, and combinedh-p-version for a one dimensional problem are presented.

A laboratory procedure for the diagnosis of pregnancy has been a subject of interest to obstetricians for many years. The early work in this field, which seemed most promising at first, has been shown to have little or no practical value. Since then, advances in physiology and endocrinology have added much to our knowledge of the function of the ductless glands and of their physiologic changes during pregnancy. It is on this fundamental work that the pregnancy tests of Aschheim and Zondek, of Brouha and of Friedman depend. In this study these three reactions, as well as the empiric reactions of Bercovitz and of Manoilov, have been performed, so far as possible, on each individual in a series of pregnant and nonpregnant patients. It is our purpose to ascertain their relative values as diagnostic procedures in gynecologic as well as obstetric cases.A large amount of experimental work has been

Summary: Biological and engineered networks have recently been shown to display network motifs: a small set of characteristic patterns that occur much more frequently than in randomized networks with the same degree sequence. Network motifs were demonstrated to play key information processing roles in biological regulation networks. Existing algorithms for detecting network motifs act by exhaustively enumerating all subgraphs with a given number of nodes in the network. The runtime of such algorithms increases strongly with network size. Here, we present a novel algorithm that allows estimation of subgraph concentrations and detection of network motifs at a runtime that is asymptotically independent of the network size. This algorithm is based on random sampling of subgraphs. Network motifs are detected with a surprisingly small number of samples in a wide variety of networks. Our method can be applied to estimate the concentrations of larger subgraphs in larger networks than was previously possible with exhaustive enumeration algorithms. We present results for high-order motifs in several biological networks and discuss their possible functions. Availability: A software tool for estimating subgraph concentrations and detecting network motifs (mfinder 1.1) and further information is available at http://www.weizmann.ac.il/mcb/UriAlon/

To examine the efficacy and toxicity of oral 3,4 diaminopyridine (DAP) in dosages up to 100 mg/day, 36 patients with multiple sclerosis (MS) enrolled in a randomized, double-blind, placebo-controlled, crossover trial. The primary outcome measure was improvement of a prospectively defined neurologic deficit, which was leg weakness in 34 patients. Secondary outcome measures included the patient's subjective response, scored manual motor testing (MMT) of leg strength, scored leg strength from videotaped motor testing (VMT), quadriceps and hamstrings strength (QMT) measured by isometric dynamometry, neuropsychological testing (NPT), ambulation index (AI), and Expanded Disability Status Scale (EDSS) score. Paresthesias and abdominal pain were common and were dose limiting in eight patients. Three patients had episodes of confusion, and one patient had a seizure while on DAP. Eight patients withdrew from the study, leaving 28 evaluable patients for the efficacy analysis. The prospectively defined neurologic deficit improved in 24 patients-22 on DAP and 2 on placebo (p = 0.0005). All improvements were in leg weakness. Subjective response and measures of leg strength and function (MMT, VMT, QMT, and AI) improved on DAP compared with placebo. Neither NPT nor EDSS scores improved. DAP treatment can induce improvements in leg strength in MS patients, but toxicity is limiting in many patients.