A set expression based inheritance system

This paper describes a new formalism for inheritance systems, based on the formal semantics of set expressions. Using the formalism, it is possible to define new semantic classes by arbitrary set expressions operating on previously defined classes. Thus generalizing bothIS-A links andIS-NOT-A links and adding the set intersection operation. We present an efficient algorithm which follows these definitions to deduce the properties implied by the inheritance network, i.e., the properties of the classes containing a given element. The application which motivated the development of the formalism, namely semantic disambiguation of natural language, is also described.     

Simultaneous over- and underconfidence: The role of error in judgment processes.

Two empirical judgment phenomena appear to contradict each other. In the revision-of-opinion literature, subjective probability (SP) judgments have been analyzed as a function of objective probability (OP) and generally have been found to be conservative, that is, to represent underconfidence. In the calibration literature, analyses of OP (operationalized as relative frequency correct) as a function of SP have led to the opposite conclusion, that judgment is generally overconfident. Reanalysis of 3 studies shows that both results can be obtained from the same set of data, depending on the method of analysis. The simultaneous effects are then generated and factors influencing them are explored by means of a model that instantiates a very general theory of how SP estimates arise from true judgments perturbed by random error. Theoretical and practical implications of the work are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dielectric properties above the glass transition for a series of epoxide prepolymers

Dielectric properties above the glass transition have been investigated for a series of bisphenol-A type epoxide prepolymers (388 ≤ M?_w ≤ 2640). Dielectric measurements were performed over a frequency range of 50 Hz–1 MHz using a vertical parallel plate cell which was constructed in the laboratory. The dielectric α-relaxation for each prepolymer fits the empirical model of the Havriliak–Negami equation. The temperature dependence of the dielectric relaxation time τ is described by the Williams–Landel–Ferry (WLF) equation as well as that of the direct current conductivity σ, which can be measured using the same cell. The relationship between τ and σ, σ^· τ^m = const, is derived from experimental results. The exponent m, which depends on the molecular weight of the prepolymer, is considered to correspond to the ratio of the segmental mobility to ionic mobility. The dielectric loss ε″ can be used as an indicator of the direct current conduction in the temperatures where the ionic component in ε″ becomes much larger than the dipole one.     

Optimal Control of Solar Sludge Dryers

Optimal control (OC) methodology is used to develop a control policy for a batch-operated solar sludge dryer with ventilation as the dominant control. Batch performance criteria and instantaneous optimization criteria are developed for two economic environments: quota limited and capital limited. The general formulation, as well as simplifications resulting from the multiplicative form of the evaporation (drying) rate model, are presented. The multiplicative form results in a single constant number, called here “control intensity,” which is used to guide the on-line control decisions. These decisions turn out to be independent of the dry solids content (DSC) of the sludge. Further simplification, by assuming a strictly constant weather, is used to demonstrate the general effects of the economic and physical (weather) environment on the solution.

The OC approach is used to address, via simulation under realistic weather conditions, several design, operation, and pricing problems. In particular, the following have been considered: sizing of the ventilation fans, determination of a fair fee for sludge disposal, finding the best final DSC, and evaluating the effect of the price of electricity. Regarding the particular location represented by the data, it has been shown that the installed capacity of the ventilation fans should be increased and that there seems to be sufficient economic incentive for solar drying.     

Immunohistochemical study of epithelioid hemangioendothelioma in the leg: a case report

Epithelioid hemangioendothelioma is a relatively rare lesion. Although its histogenesis has been well described, its immunohistochemical characteristics remain controversial. A case of epithelioid hemangioendothelioma of the soft tissue of the right leg in a 67-year-old Chinese woman is reported. Histologic findings of intracytoplasmic lumina in the tumor cells and positive immunostaining for vimentin, factor VIII-related antigen. CD34 and Ulex europaeus agglutinin 1 (UEA-1) were obtained, demonstrating differentiation of the tumor cells to endothelial cells, although staining for antibodies to cytokeratins AE1/AE3 and CAM5.2 was weak. CD34 as well as Factor VIII-related antigen is a useful marker of endothelial differentiation in this tumor. A review of the literature is also presented.     

安全防护不容一丝轻忽—黑客入侵胰岛素泵的启发

不久前,我刚好有机会参加了一个医疗论坛,会议开幕演讲吸引了我的注意,因为会议上现场示范了如何以黑客手法侵入胰岛素泵。这场会议十分具有启发性,它让我们看到了黑客如何通过无线连接,从远端入侵存在安全漏洞的医疗设备。     

Antitumor activity of synthetic alkylphospholipids with or without PAF activity

1-O-Octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (ET-18-OMe) has been reported to possess definite antitumor activity in vivo. Twenty-two alkyl lysophospholipid analogs were chemically synthesized, and their antitumor activity against mouse experimental tumors (Sarcoma 180, MM46, P388) was examined. Among them, 1-O-octadecyl-2-O-acetoacetyl-rac-glycerol-3-phosphocholine was found to show antitumor activity similar to ET-18-OMe with less acute toxicity. Intravenous injection of the ET-18-OMe withsn-3 configuration retarded the subcutaneous growth of Sarcoma 180 cells effectively, while the growth inhibition by thesn-1 isomer was much less effective. This stereospecificity was similar to that observed in their activities as platelet-activating factor (PAF) agonists. The acetoacetyl compound, another PAF agonist, showed similar stereospecific antitumor action in vivo. These findings suggest that some alkyl lysophospholipids may activate host cells to a cytostatic stage against tumor cells in vivo through binding to a PAF receptor. Our preliminary results indicated that the responsible cells under these conditions might be primarily immature macrophages present in the bone marrow. No appreciable or even adverse stereospecificity was observed in the different sets of experiments where the activity of ET-18-OMe against MM46 tumor cells in vivo or the direct cytotoxicity against human promyelocytic leukemia HL-60 cells in vitro was examined. Under, some conditions, the antitumor activity of ET-18-OMe in vivo may be revealed through direct cytotoxicity and/or modulation of the host defense system by “nonspecific” mechanisms. Some alkylphospholipids without PAF activity may also show antitumor activity through similar, “nonspecific” mechanisms.     

Guinea pig bone marrow cells treated with platelet-activating factor generate factor(s) which affects their DNA synthesis and microbicidal activity

We have previously reported that platelet-activating factor (PAF) induces proliferation and microbicidal activity of guinea pig bone marrow cells. In the present study, we have found that the conditioned medium of PAF- or nonmetabolizable PAF agonist-treated guinea pig bone marrow cells augmented DNA synthesis and induced microbicial activity of bone marrow cells. A PAF specific antagonist, CV-6209, inhibited generation of the active conditioned medium by PAF. Addition of the PAF antagonist only partially suppressed the augmentative effect of the active conditioned medium on DNA synthesis; this is consistent with the fact that, because of the rapid breakdown, no appreciable amount of PAF remained in the conditioned medium of PAF-treated cells. Although mouse bone marrow cells did not respond to PAF unlike guinea pig cells, their DNA synthesis was significantly enhanced by the conditioned medium of PAF-treated guinea pig bone marrow cells. Thus, some newly generated factor(s) distinct from the originally inoculated PAF seemed to modulate the bioactions of PAF on bone marrow cells. An appreciable amount of PAF was produced by calcium ionophore-treated guinea pig bone marrow cells. These findings indicate that PAF synthesized in guinea pig bone marrow cells induces generation in the cells of some factor(s) which affects proliferation or microbicidal activity. Presented at The Third International Conference on Platelet-Activating Factor and Structurally Related Ether Lipids, Tokyo, Japan, May 1989.