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We performed a numerical analysis to study the orientation distribution of a dilute suspension of thin, rigid, rod-like nanoparticles under shearing flow near a solid boundary of weak confinement. Brownian dynamics simulation of a rod was performed under various ratios of shear rate and rod diffusivity (Peclet number), as well as the center-of-mass position (wall confinement). We discuss the effects of Peclet number and wall confinement on the angle distributions, Jeffery orbit distribution and average orientation moments. The average orientation moments, obtained as a function of Peclet number and wall confinement, can be used to improve a previous shear-induced migration model. We demonstrate that the improved model can give excellent prediction of the orientation moment distributions in a microchannel flow. [ABSTRACT FROM AUTHOR]

While all 2-methylene-19-nor analogs of 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) tested produce an increase in epidermal thickness in the rhino mouse, only a subset reduce utricle size (comedolysis). All-trans retinoic acid (atRA) also causes epidermal thickening and a reduction in utricle size in the rhino mouse. We now report that 2-methylene-19-nor-(20S)-1α-hydroxybishomopregnacalciferol (2MbisP), a comedolytic analog, increases epidermal thickening more rapidly than does atRA, while both reduce utricle area at an equal rate. Whereas unlike atRA, 2MbisP does not alter the epidermal growth factor receptor ligand, heparin-binding epidermal growth factor-like growth factor, it does increase the expression of both amphiregulin and epigen mRNA, even after a single dose. In situ hybridization reveals an increase in these transcripts throughout the closing utricle as well as in the interfollicular epidermis. The mRNAs for other EGFR ligands including betacellulin and transforming growth factor-α, as well as the epidermal growth factor receptor are largely unaffected by 2MbisP. Another analog, 2-methylene-19-nor-(20S)-26,27-dimethylene-1α,25-dihydroxyvitamin D3 (CAGE-3), produces epidermal thickening but fails to reduce utricle size or increase AREG mRNA levels. CAGE-3 modestly increases epigen mRNA levels, but only after 5 days of dosing. Thus, 2-MbisP produces unique changes in epidermal growth factor receptor ligand mRNAs that may be responsible for both epidermal proliferation and a reduction in utricle size. [ABSTRACT FROM AUTHOR]

Current expert system technology is 30 years old. Expert system shells find their origins in the work of early expert systems, most notably MYCIN which was developed at Stanford in the mid-1970s. Even Prolog programmers are settling for less robust reasoning power. The logic programming community (from which both expert systems and Prolog arose) has made notable advances since those times. These advances are lacking from current expert system technology. The advances include a well-developed theory of multiple forms of negation, an understanding of open domains and the closed world assumption, default reasoning with exceptions, reasoning with respect to time (i.e. a solution to the frame problem, and introspection with regard to previous beliefs), reasoning about actions, introspection, and maintaining multiple views of the world simultaneously. The contribution of this paper is to discuss these developments in a singular, integrated, practical, digestible manner. Some of these ideas exist in a variety of papers spread across decades. They also exist in the minds of a very small community of researchers. Some of these ideas are unpublished. The presentation in this paper is from a different point of view, and intended to be more comprehensive and pedagogical. The presentation is also intended to be accessible to a much wider audience. Both the synthesis and the simplicity of this presentation are absent from the literature. [ABSTRACT FROM AUTHOR]

This article describes the 2005 Worldwide Interoperability Demonstration held by the Optical Internetworking Forum and showcased during SUPERCOMM 2005. The event high-lighted Ethernet services transported over intelligent optical networks, using equipment from 13 of the industry's leading vendors located in seven carrier laboratory facilities around the world. The demonstration utilized a distributed optical control plane based on OIF Implementation Agreements to control a multilayer network providing Ethernet over SONET/SDH adaptation and transport. The article describes the global test network, services, architecture, and overall test approach. It also describes innovations made to the optical control plane to handle multilayer signaling and lists further refinements needed to make these services operational. [ABSTRACT FROM AUTHOR]

This article reports that the "Optical Internetworking Forum," (OIF) conducted a World Interoperability Demonstration in conjunction with SUPERCOMM Inc., another telecommunication company. The demonstration was held in Chicago during June 22-24, 2004. The demonstration was executed on a global stage with seven carriers across three continents Internet through an intelligent control plane in a multivendor environment of 15 vendor participants. The success of the demonstration validated the work of the OIF in promoting carrier deployment of integrated data and optical network technologies. It demonstrated leading edge technologies in both the control and transport planes. The control plane provides an automated method of managing connections, while the data adaptations in the transport plane provide flexible and efficient transport. The OIF World Interoperability Demonstration marked a key milestone in maturing the underlying technologies, thus moving them closer to deployment. The remainder of this article describes the technical approach and execution of this demonstration. The preparations and scope of the event are described, including work within and between carrier laboratories.

Using students' characteristics and measures of the organizational dimensions of schools from the High School and Beyond study, the authors confirm the findings of previous studies on the importance of individual characteristics to track placement. They also show that school characteristics matter. School electivity, academic inclusiveness, and the socioeconomic composition of a school all influence track placement and interact with students' ability and socioeconomic status when additional individual variables are controlled. [ABSTRACT FROM AUTHOR]

Prior studies of the role of curriculum tracking in status maintenance have offered contradictory results, suggesting either that (1) tracking sorts chi Wren from different backgrounds into different curricular programs where they receive differential educational treatments; (2) tracking sorts children on the basis of ability rather than class background, thus facilitating social mobility; or (3) while tracking may sort children, it has little effect upon educational outcomes and thus has no role in status maintenance. This paper uses 1980s data from the High School and Beyond Study to estimate the effects of curriculum tracking over a two-year period on a number of dependent variables for students who have experienced only one track placement. The results show that there are substantial differences among students from different socioeconomic origins in ultimate track destination. Track location is modestly to moderately related to number of courses taken, academic performance, educational and occupational aspirations, satisfaction with school, perceived values of friends, self-esteem, extracurricular participation and leadership, enrollment in postsecondary education, disciplinary climate, and teacher treatment. A reopening of the status maintenance hypothesis is suggested. [ABSTRACT FROM AUTHOR]

Fasting free amino acid concentrations in plasma of 20 control and 18 alcoholic subjects were compared in an attempt to validate previous reports that the molar ratio of α-amino- n-butyric acid/leucine (A/L ratio) is a marker for alcoholism. We were unable to confirm the observations of either altered α-amino- n-butyric acid or leucine concentrations or an increased A/L ratio in alcoholic subjects, and we conclude that the A/L ratio is not a biochemical marker for alcoholism. [ABSTRACT FROM AUTHOR]

This paper proposes a system, a meta-reasoner, to diagnose other systems. This system, called DSKE, performs its diagnosis based upon the knowledge of the structure of the system under diagnosis and based upon previous diagnostic experiences with that system. Since DSKE is based upon first order logic, it has strong deductive powers. Given adequate information, it can diagnose problems quite impressively. Contrary to probabilistic and fuzzy logic approaches, our system is not based upon data which may or may not be available, and which may or may not be reliable. Further, our system makes use of available knowledge. Contrary to model based diagnosis systems, our system can handle uncertainty and incomplete knowledge. The algorithm we provide yields a minimal diagnosis which covers all the abnormal behaviors detected. This paper provides a detailed description of DSKE. The inner workings of the system are carefully and comprehensively analyzed. Examples illustrate the advantages of our system, and demonstrate its use. [ABSTRACT FROM AUTHOR]