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This paper examines the possibility of handling treatment effects as a fuzzy relational problem with particular reference to ophthalmology. An ophthalmological evaluation is considered to consist of two major stages. Firstly, an explanation of a patient's eye-health state in terms of known disease labels is formulated through diagnosis. Secondly, the effectiveness of a therapeutic strategy designed to restore a patient's normal eye-health, is then predicted via prognosis. The paper considers the latter aspect in the sense of assessing the effects of medical intervention by comparing pre- and post-therapeutic fuzzy subsets.  相似文献   
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A philosophical formalism of a new methodological aspect of humanistic systems design and evaluation is given. A requisite concept of context-dependency is highlighted, and some approaches to fuzzy sets and linguistics subsequently extended. It is consequently shown that a mathematical theory of pragmatic fuzzy subsets is not only conceptually possible but practically implementable in man-machine studies as well. Thus, the important context-dependent implication of the subjective nature of Zadeh's theory of fuzzy sets can be better exploited.As a pragmatic theory, the approach here is a seeming connection between pragmatism and ontology, concepts that are traditionally diametrically opposed to each other. The attitude adopted has been the equation of pragmatism and psychophysical measurements of ontological objects (noumena). Pragmatism is tacitly defined as a form of empiricism whereby linguistic constructs (i.e., linguistic-variable denotions) that represent any aspect(s) of a humanistic system are nothing more than an operational procedure used to achieve psychophysical measurements of the aspect(s). In this fashion, pragmatism would enable the contents of assertions, which are made through declarative propositions, about humanistic systems to be deciphered within relevant contexts. For pragmatism, direct sense experience provides both the meaning and the criterion of reality judgements. The context-dependent nature of the physical reality of ontological entities is, therefore, better understood pragmatically vis-a-vis the appropriate evaluative criteria and interpretative conventions.By emphasizing the distinction between a fuzzy system (naturally fuzzified) and a fuzzified mathematical structure (meta-mathematically fuzzified), the use of the standard fuzzy topologies is justified although it is conceptually possible to develop a yet more general topology or perhaps an alternative one especially in the case of a meta-mathematically fuzzified structure. However, for the express purpose of machine implementation, a naturally fuzzified system, such as a (complex) humanistic system, is more amenable to an initial test of the philosophy of pragmatic fuzzy subsets. Consequently, the fuzzy topology and spaces employed are intended to be devoid of extensive generalities, in this instance.  相似文献   
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The fumigant toxicity of Xylopia parviflora (A. Rich.) Benth (Annonaceae) root bark's essential oil (EO) against cowpea seed bruchid, Callosobruchus maculatus, was investigated in the laboratory. Dose had significant (P < 0.0001) effect on mortality at 6 hours after treatment (HAT) at a concentration of 6.25 μL/mL air which exerted 81.70% mortality, while there was no mortality in all other lower doses. At 12 HAT, 75.05% and 90.00% mortality were observed at doses of 3.15 and 6.25 μL/mL air, respectively. It was significantly (P < 0.05) higher than the mortality (50.58%) observed when 0.78 μL/mL air was applied. The lethal time for 50% of assayed adults (LT50) obtained when the bruchid was exposed to X. parviflora EO at a dose of 6.25 μL/mL air (2.71 h) was significantly lower than LT50 obtained at exposure of bruchid to other lower doses of 0.78–3.15 μL/mL air.  相似文献   
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Chalcone and 4-methoxychalcone react with chlorosulfonic acid to give chalcone-p-sulfonyl chloride and 4-methoxchalcone-3-sulfonyl chloride respectively. The sulfonyl chlorides were converted into 13 sulfonyl derivatives by reaction with nucleophiles. With hydrazine and phenylhydrazine the chalconesulfonyl chlorides were cyclised to the corresponding hydrazinopyrazolines. In contrast, with N,N-dimethyl-hydrazine only the dimethylsulfonohydmides were obtained, and no attack on the carbonyl group was observed. Possible reasons for this difference in behaviour are discussed, together with spectroscopic evidence for the structures proposed.  相似文献   
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Criteria for the existence of uniformly dissipative solutions for a certain fifth order non-linear differential equation are given by means of the frequency domain method.  相似文献   
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This paper reports on the surface modification of plastic microfluidic channels to prepare different biomolecule micropatterns using ultraviolet (UV) photografting methods. The linkage chemistry is based upon UV photopolymerization of acryl monomers to generate thin films (0.01-6 microm) chemically linked to the organic backbone of the plastic surface. The commodity thermoplastic, cyclic olefin copolymer (COC) was selected to build microfluidic chips because of its significant UV transparency and easiness for microfabrication by molding techniques. Once the polyacrylic films were grafted on the COC surface using photomasks, micropatterns of proteins, DNA, and biotinlated conjugates were readily obtained by surface chemical reactions in one or two subsequent steps. The thickness of the photografted films can be tuned from several nanometers up to several micrometers, depending on the reaction conditions. The micropatterned films can be prepared inside the microfluidic channel (on-chip) or on open COC surfaces (off-chip) with densities of functional groups about 10(-7) mol/cm2. Characterization of these films was performed by attenuated-total-reflectance IR spectroscopy, fluorescence microscopy, profilometry, atomic force microscopy, and electrokinetic methods.  相似文献   
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Treatment of several substituted benzils [3,3′- and 4,4′-dimethyl-; 2,2′-, 3,3′- and 4,4′-dichloro-; 3,3′-dibromo-; 4-(N,N-dimethylamino)-] with an excess of chlorosulfonic acid gave the corresponding 3-chloro-2-phenylbenzofuran disulfonyl dichlorides. Disubstitution was confirmed by microanalytical and spectral data for the corresponding bis(N,N-dimethylaminsulfonamides). The positions of electrophilic substitution were not confirmed with 3,3′-dimethyl-, 2,2′- and 3,3′-dichlorobenzils. With 4,4′-dichlorobenzil, a smaller amount of chlorosulfonic acid enabled the isolation of 3,6,4′-trichloro-2-phenylbenzofuran-5-sulfonyl chloride, which was identified by X-ray analysis of the N,N-dimethylsulfonamide. The cyclisation failed with 3,3′-dimethoxy-, and 3,3′- and 4,4′-dinitrobenzils. The results have been interpreted mechanistically.  相似文献   
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2,3-Diphenylpyrazine, 3,4-diphenylfurazan and 2-methyl-4,5-diphenyl oxazole react with chlorosulfonic acid to give the sulfonyl chlorides Ia, IIa, IIIa. The chlorides were condensed with nucleophiles to give thirteen derivatives. 4′,4″-bis-Dimethylsulfamoyl-2-methyl-4,5-diphenyloxazole (Illb) was oxidized with bromine to give 4,4′-bis-dimethylsulfamoylbenzil (IV), which by heating with ethylenediamine afforded the 4′,4″-bis-dimethylsulfamoylpyrazine (V). The spectral data of the various compounds are briefly discussed.  相似文献   
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