Time-dependent mechanical properties of high-strength cements

A high-strength cement paste based on aluminous cement with the addition of water-soluble polymer was found to have a flexural strength which increased at about 12 MPa per decade increase in strain rate over the range 10⁻⁶ to 10⁻² sec⁻¹. The effect of soaking in water was to markedly reduce the strength. Swelling occurred on soaking in water for both Portland and aluminous cement-based pastes but was more gradual for the latter. Wetting swelling and drying shrinkage increased with polymer content for Portland-based pastes. Creep and stress relaxation in one type of Portland cement-based paste and in aluminous cement-based paste were markedly increased by soaking, but in a second type of Portland-based paste there was little effect. These effects are attributed to the polymer content of the pastes and its distribution in the pastes.     

Eignungsvergleich verschiedener Schwarzpappelhölzer zur Zellstoffgewinnung

Zusammenfassung Beschreibung der untersuchten 1 Schwarzpappelarten. Wicktebestimmungen. Faserl?ngenmessungen. Mikroskopische Untersuchungen an Holzquerschnitten. Analysen der H?lzer. Bestimmung des Reinzellulosegehaltes und der Baftfestigkeit der Pentosane nach drei verschiedenen Verfahren: Chlorierung, Sulfataufschlu? und Natriumchloritaujschlu?. Erkl?rung für die au?erordentlich hohen Festigkeiten der Zellstoffe im Gebiete optimaler Ausbeute. Die überlegenheit der Pappelh?lzer gegenüber Buchenholz zur Herstellung von Papier- und Kunstfaserzellstoffen. Zusammenfassung.     

Pro-epileptic changes in synaptic function can be accompanied by pro-epileptic changes in neuronal excitability

Repetitive sensory input, stroboscopic lights or repeated sounds can induce epileptic seizures in susceptible individuals. In order to understand the process we have to consider multiple factors. The output of a set of neurones is determined by the amount of excitatory synaptic input, the degree of positive feedback and their inherent electrical excitability, which can be modified by synaptic inhibition. Recent research has shown that it is possible to separate these phenomena, and that they do not always behave in unison.     

Extension of efficient predictive control to the nonlinear case

The combined use of the closed‐loop paradigm, an augmented autonomous state space formulation, partial invariance, local affine difference inclusion, and polytopic invariance are deployed in this paper to propose an NMPC algorithm which, unlike earlier algorithms that have to tackle online a nonlinear non‐convex optimization problem, requires the solution of a simple QP. The proposed algorithm is shown to outperform earlier algorithms in respect of size of region of attraction and online computational load. Conversely, for comparable computational loads, the proposed algorithm outperforms earlier algorithms in terms of optimality of dynamic performance. Copyright © 2005 John Wiley & Sons, Ltd.     

固定蜂窝系统话音质量

对话音质量的评断往往非常主观，而“用户平均评价记分（ＭＯＳ）”方法则能提供一个较为客观的评价，休斯网络系统（ＨＮＳ）的ＧＭＨ２０００固定蜂窝系统获得了极高的ＭＯＳ，这意味着该系统提供的话音品质很高。本文介绍了影响固定蜂窝系统话音质量的一些关键因素，对模拟和数字数字蜂窝系统的ＭＯＳ评价作了比较，最后简述了ＧＭＨ２０００高话音品质的原因。     

In vivo growth of Epstein-Barr virus transformed B cells with mutations in latent membrane protein 2 (LMP2)

Epstein-Barr virus (EBV) causes infectious mononucleosis in adolescents and is associated with malignant B lymphocyte proliferation in AIDS patients, patients undergoing immune suppression for organ transplantation, and SCID mice. In vitro, EBV transformed, latently infected lymphoblastoid B cell lines (LCLs) contain EBV episomes and express nine virus encoded proteins. Six are nuclear proteins (EBNAs) and three are the integral membrane proteins, LMP1, LMP2A, and LMP2B. To determine if LMP2 was essential for in vivo growth, SCID mice were injected with LCLs containing wild-type EBV (LMP2+) or with LCLs transformed with EBV containing mutations in either LMP2A or LMP2B (LMP2-). SCID mice injected with the LMP2+ or LMP2- LCLs were monitored for tumor development, length of time to tumor development, and phenotypic characterization of the resulting tumors. No difference was observed in any of the above parameters between LMP2+ and LMP2- LCLs demonstrating that LMP2 is not essential for the in vivo growth of EBV transformed B lymphocytes in SCID mice.     

The latent structure of schizotypy: I. Premorbid indicators of a taxon of individuals at risk for schizophrenia-spectrum disorders.

A taxometric analysis (R. R. Golden & P. E. Meehl, 1979) was conducted to test the hypotheses that liability for schizophrenia-spectrum disorders is dichotomously distributed and that this liability can be detected premorbidly with behavioral indicators analogous to many of the criteria for schizotypal personality disorder. Behaviors were assessed in 207 offspring of schizophrenic mothers and 104 matched offspring of normal parents in 1962, when participants' mean age was 15 years. Diagnoses on the basis of the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) were made in 1986–1989, when participants were nearly through the risk period for developing schizophrenia. The aggregation of indicators was consistent with a bimodal latent liability distribution. Membership in the schizotypal class was a sensitive and specific predictor of the emergence of schizophrenia-spectrum disorders in adulthood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Iterative fuzzy image segmentation

The multispectral signature of features has been used for identification of objects in remotely sensed scenes for a number of years. Recently these techniques have been applied to feature selection in natural scenes. Due to the inherent noise and degradation of the input cues to the algorithms, meaningful image segmentation is a difficult process. In an effort to reduce the sensitivity of a system to these problems, we have been led to the development of a iterative fuzzy clustering technique for image segmentation. It is believed that this method represents an image segmentation scheme which can be used as a preprocessor for a multivalued logic based computer vision system.