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61.
This study presents a method for the detection of outliers based on the Variable Precision Rough Set Model (VPRSM). The basis of this model is the generalisation of the standard concept of a set inclusion relation on which the Rough Set Basic Model (RSBM) is based. The primary contribution of this study is the improvement in detection quality, which is achieved due to the generalisation allowed by the classification system that allows a certain degree of uncertainty. From this method, a computationally efficient algorithm is proposed. The experiments performed with a real scenario and a comparison of the results with the RSBM-based method demonstrate the effectiveness of the method as well as the algorithm’s efficiency in diverse contexts, which also involve large amounts of data.  相似文献   
62.
The objective of this transversal study was to determine folate and iron nutritional status of women in fertile age from Municipio Jiménez, Lara State, Venezuela. The sampling was probabilistic by conglomerates from the urban and rural areas, selecting 15 conglomerates from which women between 12 and 45 years (269), were studied. After signing informed consent, participating were interviewed for personal data, antecedents related to folate and iron, socioeconomic data (Graffar-Mendez Castellano method and unsatisfied basic needs). In blood sample was determined Hemoglobin, and Erythrocytic Folate (FE). Serum was obtained to determine Ferritin and Serum Folate (FS). 53.53% of the sample presented low FS levels, 10.78% were FS deficient. Severe FE deficiency was present in 80.7% of the cases, moderate deficiency affected 5.9%. For both tests, median was higher for women in treatment with Acido Fólico or pregnant (p = 0.000), median for FE was higher for adults (p = 0.001) and in non poor women (p = 0.011). There were no significant differences for coffee, alcohol, anticonceptive consumption, urban or rural resident or socioeconomic strata. The prevalence of anemia was 11.2% being significantly more frequent in adults than in adolescents (p = 0.029) and in urban women (p = 0.042). Low ferritin were found in 37.3% of the sample, the effect of different variables was not statistically significant. In conclusion, there is a high prevalence of iron and folate deficiencies in women of fertile age from Municipio Jiménez, which could constitute a conditioning factor for the appearance of neural tube defects.  相似文献   
63.
We show that any compact, orientable, piecewise-linear two-manifold with Euclidean metric can be realized as a flat origami, meaning a set of non-crossing polygons in Euclidean 2-space ??plus layers??. This result implies a weak form of a theorem of Burago and Zalgaller: any orientable, piecewise-linear two-manifold can be embedded into Euclidean 3-space ??nearly?? isometrically. We also correct a mistake in our previously published construction for cutting any polygon out of a folded sheet of paper with one straight cut.  相似文献   
64.
To evaluate the effective implantation of a specific protective culture of Penicillium nalgiovense, a real-time quantitative PCR (qPCR) using SYBR Green methodology was developed. Two specific primers were designed on the basis of the published partial sequences of the Internal Transcribe Spacer (ITS)1–5.8S-ITS2 region of various strains of P. nalgiovense. Using the developed method, a PCR product of 51 bp with a T m value 81.34 °C was detected. T m values of the amplified product allowed specific differentiation between P. nalgiovense and the remaining mould species tested. The developed qPCR method was tested on inoculated slices of dry-cured sausage (‘salchichón’) showing an efficiency of 97.24 %, a R 2 value of 0.99 and a detection limit of P. nalgiovense of 1 log colony-forming units (cfu)/cm2. The qPCR method demonstrated that the protective strain of P. nalgiovense grew and competed against an ochratoxin A (OTA)-producing Penicillium verrucosum strain on commercial dry-cured sausage. This qPCR method provides a specific, accurate and sensitive detection and quantification of P. nalgiovense on dry-cured sausage salchichón in order to estimate its colonization during their processing. This assay will improve strategies to prevent and control unwanted mould colonization and OTA risk in dry-cured meat commodities.  相似文献   
65.
The stability of bivalve molluscs was studied in live mussels (Mytilus galloprovincialis) packaged under modified atmospheres. Studies of physical, chemical, microbiological and sensory parameters have detailed these changes in the live packaged mussels. The highest survival was achieved at high oxygen concentrations, i.e. 75%, in the absence of carbon dioxide. The improved storage conditions promote shelf life in 80% of the packaged mussels, reaching a storage life of 6 days when held at 2–3 °C, whereas control molluscs packaged in air did not exceed 3–4 days when stored under the same conditions. Sensory analysis of cooked products from live mussels packaged under 75% oxygen:25% nitrogen were optimum throughout the period of storage. Secondly, the results for the most effective treatment were compared with those for an approximate 75–80% oxygen mixture achieved by applying partial vacuum to the packaging machine. This option employed only oxygen and decreased packaging time, which reduced mussel packaging stress by avoiding elevated vacuum conditions. It provided operational and economic advantage to commercial mussel packaging.  相似文献   
66.
A novel antifungal antibiotic, UK-3A, was obtained from the mycelial cake of Streptomyces sp. 517-02. UK-3A was very similar in structure to UK-2A, a structural relative of antimycin A. The antifungal spectrum of UK-3A was relatively broad (MICs for yeasts and filamentous fungi: 1.56-6.25 and 0.39-1.56 micrograms/ml, respectively). The cytotoxic activity of UK-3A was weak (IC50: 18-100 micrograms/ml).  相似文献   
67.
Polycarbazole (PCZ) was obtained by electrochemical oxidation of carbazole monomers. Two potentials were used: the oxidation potential of the monomer 1700 mV and an over oxidation potential 2500 mV. The carbazole monomers were supplied either in solution in the electrolyte or in the form of pre-deposited thin film evaporated on a working electrode. It is shown that if PCZ is systematically obtained its electrical and morphological properties are strongly dependent on the experimental conditions. The stability of over-oxidized PCZ films corresponds to chain reticulation beyond the first oxidation potential value, with the loss of flexibility of the chains and steric hindrance, which decreases the carrier mobility and, therefore, its conductivity. The polymers obtained at the oxidation of carbazole have conductivity corresponding to higher carrier mobility. These polymers are conjugated. Moreover, in the case of preevaporated carbazole thin film the coverage of the SnO2 is very high and the films are homogenous.  相似文献   
68.
The Cyto-Shuttle (Cancer Diagnostics, Inc., Fairfax, VA) monolayer preparation method was compared to our routine cytocentrifuge method in 129 fluid cytology cases. A single sample from each case was split and prepared by each method. The Cyto-Shuttle preparation was superior to the cytocentrifuge preparation in 51% of cases, equal to it in 38%, and inferior to it in 11%: bronchial wash/lavage (45 cases), 38%, 49%, 13%; body cavity fluid (39 cases), 72%, 15%, 13%; urine (18 cases), 56%, 44%, 0%: peritoneal washing (16 cases), 44%, 44%, 12%; and miscellaneous (11 cases), 36%, 55%, 9%. Cyto-Shuttle preparations were superior due to decreased background and increased number of cells per slide; fixation and morphology were generally equivalent to cytocentrifuge preparations.  相似文献   
69.
Motivated by applications in data compression, debugging, and physical simulation, we consider the problem of adaptively choosing locations in a long computation at which to save intermediate results. Such checkpoints allow faster recomputation of arbitrary requested points within the computation. We abstract the problem to a server problem in whichk servers move along a line in a single direction, modeling the fact that most computations are not reversible. Since checkpoints may be arbitrarily copied, we allow a server to jump to any location currently occupied by another server. We present on-line algorithms and analyze their competitiveness. We give lower bounds on the competitiveness of any on-line algorithm and show that our algorithms achieve these bounds within relatively small factors.This work was done partly while at Courant Institute, New York University, NY 10012, USA.This research was supported in part by NSF Grant CCR-8947792.  相似文献   
70.
Flipping Cubical Meshes   总被引:1,自引:1,他引:0  
We define and examine flip operations for quadrilateral and hexahedral meshes, similar to the flipping transformations previously used in triangular and tetrahedral mesh generation. ID="A1" Correspondence and offprint requests to: M. Bern, Xerox Palo Alto Research Center, 3333 Coyote Hill Rd., Palo Alto, CA 94304, USA. E-mail: bern@parc.xerox.com  相似文献   
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