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The growing numbers of golf communities are attracting a diverse group of homebuyers who experience varying levels of neighborhood satisfaction. A multinomial logistic regression analysis with follow-up ANOVA reveals that homeowners in one region of Spain who believe there are more advantages than disadvantages to living in a golf community are more likely to be older, Spanish, and evaluate the natural environment, sports facilities, and water supply of their community as better. Meanwhile, those who perceive more disadvantages cite the limitations on using the golf course for non-golf activities, high housing costs, automobile dependence, and lack of services and shops. Thus, satisfaction with the golf community varies depending on the residents’ personal characteristics as well as their evaluation of the neighborhood’s characteristics, but is not directly attributable to whether they play golf or whether the course was a decisive factor in choosing the house.  相似文献   
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The aim of this study was to evaluate the antimicrobial activity, pH level, calcium ion release, and radiopacity of calcium hydroxide pastes associated with three radiopacifying agents (iodoform, zinc oxide, and barium sulfate). For the pH and calcium release tests, 45 acrylic teeth were utilized and immersed in ultrapure water. After 24 h, 72 h, and 7 days the solution was analyzed by using a pH meter and an atomic absorption spectrophotometer. Polyethylene tubes filled with the pastes were used to perform the radiopacity test. For the antimicrobial test, 25 dentin specimens were infected intraorally in order to induce the biofilm colonization and treated with the pastes for 7 days. The Live/Dead technique and a confocal microscope were used to obtain the ratio of live cells. Parametric and nonparametric statistical tests were performed to show differences among the groups (P < 0.05). The pH analysis at 7 days showed significant differences (P < 0.05) among the groups. No differences among the pastes were found in the calcium release test on the 7th day (P > 0.05). The calcium hydroxide/iodoform samples had the highest radiopacity and antimicrobial activity against the biofilm‐infected dentin in comparison to the other pastes (P < 0.05). Calcium hydroxide mixed with 17% iodoform and 35% propylene glycol into a paste had the highest pH, calcium ion release, radiopacity, and the greatest antimicrobial action versus similar samples mixed with BaSO4 or ZnO. Microsc. Res. Tech. 78:620–625, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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A new simple analytical method for monitoring propyl propane thiosulfonate (PTSO) in animal feed is presented. PTSO is an active ingredient from Allium spp. (like onion and shallot), proposed as a natural additive for feed being an efficient alternative to antibiotics used as growth promoter due to its efficiency improving animal health. Reversed-phase liquid chromatography with UV detection has been used and a previous sample treatment based on solid-liquid extraction has been developed and optimized in order to extract PTSO from a feed for laying hens using acetone as extraction solvent. The method has been characterized obtaining limits of detection and quantification of 11.2 and 37.3 mg kg?1, respectively, which are lower than the concentrations expected in samples containing this additive. The intra- and interday relative standard deviations (RSDs) were lower than 8.3 % in all the cases, and recoveries varied from 90.2 to 94.6 %. Finally, in order to check the unequivocal identification of PTSO, mass spectrometry detection was applied. The proposed method is a simple procedure for monitoring PTSO in commercial feed, being possible to implement it in routine laboratories for quantification purposes and stability studies of the distributed products.  相似文献   
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Convolutional tailbiting codes are widely used in mobile systems to perform error-correcting strategies of data and control information. Unlike zero tail codes, tailbiting codes do not reset the encoder memory at the end of each data block, improving the code efficiency for short block lengths. The objective of this work is to propose a low-complexity maximum likelihood decoding algorithm for convolutional tailbiting codes based on the Viterbi algorithm. The performance of the proposed solution is compared to that of another maximum likelihood decoding strategy which is based on the A* algorithm. The computational load and the memory requirements of both algorithms are also analysed in order to perform a fair comparison between them. Numerical results considering realistic transmission conditions show the lower memory requirements of the proposed solution, which makes its implementation more suitable for devices with limited resources.  相似文献   
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Most Unified Modeling Language (UML) computer-aided software engineering tools have been insufficient in the development process because they provide little support for conceptual model testing. Model testing aims to ensure the correctness of a UML/OCL class diagram, or, in other words, that a given class diagram can perfectly meet the user’s requirements. This study proposes the validation of class diagrams with black-box testing, a technique used to test software without focusing on the software’s implementation or structure. An approach is proposed for the automatic transformation of the constraints of a UML/OCL class diagram into test cases. Following the creation of the test cases, they are executed with JUnit and the results produced are shown to the tester. To demonstrate the applicability of this approach, an effectiveness evaluation and an efficiency evaluation are performed here. Evaluation studies show that all faults included in a class diagram have been detected within an efficient time.  相似文献   
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When switching between tasks, participants are sometimes required to use different response sets for each task. Thus, task switch and response set switch are confounded. In 5 experiments, the authors examined transitions of response within a linear 4-finger arrangement. A random baseline condition was compared with the cuing of specific response subsets grouped by hand or by finger equivalence, and these subsets were examined in both single task and task-switching designs. Results showed that part of the task switch cost is associated with switching between response sets. Furthermore, the analysis revealed a novel effect: When task switching and repetition trials are mixed, a bias towards switching the response and/or hand is found in task repetition trials. Response repetition is hindered when a task switch is expected, even for those trials when a switch of task does not occur. The results demonstrate executive processes involved in task set configuration closely depend on the motoric processing of the response set. The results are also important for current theories of task set control. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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BACKGROUND: Crop residues as wheat straw are potential sources for fuel‐ethanol production as an alternative to current production based on starch‐ or sugar‐containing feedstocks. In this work, the effect of liquid hot water (LHW) process parameters, i.e. temperature (170 and 200 °C), residence time (0 and 40 min), solid concentration (5% and 10% (w/v)) and overpressure applied in the reactor (30 bar and no overpressure), on pretreatment of wheat straw was studied using a full factorial experimental design. Pretreatment effectiveness was evaluated based on the composition of the solid and liquid fractions obtained after filtration of pretreated material, and the susceptibility of the solid fraction to enzymatic hydrolysis (EH) using commercial cellulases. RESULTS: Statistical analysis showed that only temperature and time, within the limits of the experimental range, have a significant effect on the responses studied. While the effect of pretreatment time in hemicellulose‐derived sugar recovery in prehydrolyzate depends on temperature, EH yield was enhanced as both temperature and time were increased. Maximum EH yield was 96 g glucose per 100 g potential glucose in pretreated residue. Xylan and acetyl groups content remaining in solid residue after pretretament, which were found to be directly correlated, had a marked effect on pretreated substrate degradability. CONCLUSIONS: LHW is an effective pretreatment to enhance the potential of wheat straw as substrate for ethanol production. Maximum hemicellulose‐derived sugar recovery (53% of content in raw material) and EH yield (96% of theoretical) fall within different temperature and time intervals, suggesting separate optimization designs for these responses. Copyright © 2007 Society of Chemical Industry  相似文献   
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