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Marked point processes provide a rigorous framework to describe a scene by an unordered set of objects. The efficiency of this modeling has been shown on line network extraction with models manipulating interacting segments. In this paper, we extend this previous modeling to polylines composed of an unknown number of segments. Optimization is done via simulated annealing using a Reversible Jump Markov Chain Monte Carlo (RJMCMC) algorithm. We accelerate the convergence of the algorithm by using appropriate proposal kernels. Results on aerial and satellite images show that this new model outperforms the previous one.  相似文献   
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Three new bleach activators for cotton containing pyridinium (PBBC), nicotinamido (NABBC), and 3‐methylpyridinium (3‐PBBC) cationic groups were synthesized and characterized by 1H NMR and HPLC–mass spectrometry. They were then applied to cotton fabric in a bleaching process and evaluated for their performance against the prototype N‐[4‐(triethylammoniomethyl)benzoyl]butyrolactam chloride (TBBC) at a relatively low bleaching temperature (55 °C) and pH 8.5. Measurement of Commission internationale de l’éclairage (International Commission on Illumination) (CIE) whiteness index (WI) values showed that PBBC (WI = 64), NABBC (WI = 58), and 3‐PBBC (WI = 71) impart a significant increase in CIE whiteness compared to a control sample (WI = 40). Among the three new activators, 3‐PBBC exhibited the best performance. Its WI was comparable to that of fabric bleached using the prototype bleach activator TBBC. The acute toxicity of TBBC and the new bleach activators was evaluated using the microcrustacean Daphnia similis. The chronic toxicity of TBBC and 3‐PBBC was evaluated using the green alga Raphidocelis subcapitata, and mutagenicity was evaluated in the Salmonella/microsome assay using the strain TA100. 3‐PBBC was 86 times less toxic to D. similis, 18 times less toxic to R. subcapitata, and 10 times less mutagenic to TA100 in comparison with TBBC.  相似文献   
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The administration of active compounds by the oral mucosa is an efficient method for the delivery of drugs and nutrients. This work aimed to develop and characterize orally disintegrating films (ODFs) based on starch and gelatin as carriers of vitamin C. The ODFs were produced using a casting technique by varying the concentrations of starch and gelatin (0, 20, 40, 60, 80, and 100 g of starch/100 g of polymer) and were characterized in relation to contact angle, opacity, surface pH, infrared spectroscopy, mechanical properties, morphology, and disintegration time (in vitro and in vivo). Additionally, the stability of vitamin C in the ODFs was evaluated by the incorporation of the dry extract of acerola (4 g/100 g of filmogenic solution). Generally, the ODFs presented hydrophilic characteristics with a neutral surface pH near the mouth, and films with higher starch concentrations showed greater rigidity. In vitro and in vivo tests indicated that ODFs may be classified as rapidly disintegrating. The ODFs produced with higher concentrations of starch showed a higher stability of the active compound, in addition to a shorter disintegration time. Starch‐ and gelatin‐based ODFs can be considered a new system for administering active ingredients via the oral mucosa. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44841.  相似文献   
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Summary Two types of UV-cured coating were deposited on wheat gluten film to improve the water vapor barrier properties of this highly interesting natural film in such application as fresh produces packaging. The use of an epoxy acrylate and an urethane acrylate coating allowed to reduce by half the water solubility and the water vapor permeance of the gluten film. Concerning the mechanical properties, the new bilayer films were more resistant but less resilient and flexible than the control gluten film. But the good adhesion between each UV coating and the gluten film increased the interest for these original materials. Received: 9 July 1999/Revised version: 24 March 2000/Accepted: 24 March 2000  相似文献   
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The objectives of this study were to evaluate the effect of the metaphylactic use of a semi-synthetic long-acting macrolide (tildipirosin) on the prevention of pneumonia and otitis in preweaning Holstein calves, as well as its effects on the microbiome of their upper respiratory tract (URT) and feces. Newborn healthy Holstein heifers, collectively housed, were randomly allocated to 1 of 2 treatment groups: treatment (TRT; n = 932) or control (CTR; n = 927). Calves in the TRT group received a single subcutaneous injection of 4 mg/kg tildipirosin (Zuprevo, Merck Animal Health) at 7 ± 7 d of life. Calves in the CTR group received no drug injection. All enrolled calves were evaluated from 1 to 63 ± 3 d of life (weaning age) and monitored daily for any adverse health events during this period. Daily physical examination was performed to diagnose pneumonia and otitis, and body weight was measured weekly in all animals. From a randomly selected subset of 217 calves, blood samples for biochemical variables analysis and swabs were collected weekly from the URT and rectum for analysis of the nasal and fecal microbiome, respectively, via next-generation sequencing of the 16S rRNA gene. Total bacterial load was evaluated using quantitative PCR. In addition, another subset of 26 calves was randomly selected and fecal swabs were collected in a more intensive sampling to investigate the short-term effect of tildipirosin administration on the fecal microbiome. We performed general mixed linear models and logistic regression to analyze continuous and binary outcomes, respectively. Tildipirosin metaphylaxis reduced the incidence of otitis (CTR = 47.03%; TRT = 37.55%) and tended to reduce the incidence of pneumonia (CTR = 20.71%; TRT = 17.38%) and the overall mortality risk (CTR = 6.69%; TRT = 4.94%). We observed no significant differences between groups for mortality due to pneumonia (CTR = 0.86%; TRT = 0.97%) or mortality due to otitis (CTR = 2.05%; TRT = 1.39%). Calves in the TRT group had a higher average daily gain than calves in the CTR group. Furthermore, metaphylaxis had no significant effects on the total bacterial load, genus, or phylum analysis of the fecal microbiome from the 2 subset groups. However, for the URT microbiota, we observed a significant decrease in total bacterial load for the TRT group compared to the CTR group 1 week after metaphylactic injection. Tildipirosin metaphylaxis decreased the mean relative abundance of the genera Mannheimia, Moraxella, and Pasteurella but significantly increased the mean relative abundance of Mycoplasma. Although tildipirosin had no positive effect on Mycoplasma, it reduced the mean relative abundance of important pathogenic bacteria in the URT and had positive effects for the control of otitis. The metaphylactic use of tildipirosin can be a suitable strategy for the control of otitis on farms with a high prevalence of this disease.  相似文献   
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Evaluating effectiveness of information retrieval systems is achieved by performing on a collection of documents, a search, in which a set of test queries are performed and, for each query, the list of the relevant documents. This evaluation framework also includes performance measures making it possible to control the impact of a modification of search parameters. The program trec_eval calculates a large number of measures, some being more used like the mean average precision or recall-precision curves. The motivation of our work is to compare all measures and to help the user to choose a small number of them when evaluating different information retrieval systems. In this paper, we present the study we carried out from a massive data analysis of TREC results. Relationships between the 130 measures calculated by trec_eval for individual queries are investigated, and we show that they can be clustered into homogeneous clusters.  相似文献   
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A Level Set Model for Image Classification   总被引:7,自引:4,他引:7  
We present a supervised classification model based on a variational approach. This model is devoted to find an optimal partition composed of homogeneous classes with regular interfaces. The originality of the proposed approach concerns the definition of a partition by the use of level sets. Each set of regions and boundaries associated to a class is defined by a unique level set function. We use as many level sets as different classes and all these level sets are moving together thanks to forces which interact in order to get an optimal partition. We show how these forces can be defined through the minimization of a unique fonctional. The coupled Partial Differential Equations (PDE) related to the minimization of the functional are considered through a dynamical scheme. Given an initial interface set (zero level set), the different terms of the PDE's are governing the motion of interfaces such that, at convergence, we get an optimal partition as defined above. Each interface is guided by internal forces (regularity of the interface), and external ones (data term, no vacuum, no regions overlapping). Several experiments were conducted on both synthetic and real images.  相似文献   
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