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71.
Journal of Materials Science: Materials in Electronics - The increasing demand for lithium-ion batteries has stimulated the investigation of new compounds in order to reduce the costs and the...  相似文献   
72.
This work addresses the matching of a 3D deformable face model to 2D images through a 2.5D Active Appearance Models (AAM). We propose a 2.5D AAM that combines a 3D metric Point Distribution Model (PDM) and a 2D appearance model whose control points are defined by a full perspective projection of the PDM. The advantage is that, assuming a calibrated camera, 3D metric shapes can be retrieved from single view images. Two model fitting algorithms and their computational efficient approximations are proposed: the Simultaneous Forwards Additive (SFA) and the Normalization Forwards Additive (NFA), both based on the Lucas–Kanade framework. The SFA algorithm searches for shape and appearance parameters simultaneously whereas the NFA projects out the appearance from the error image and searches only for the shape parameters. SFA is therefore more accurate. Robust solutions for the SFA and NFA are also proposed in order to take into account the self-occlusion or partial occlusion of the face. Several performance evaluations for the SFA, NFA and theirs efficient approximations were performed. The experiments include evaluating the frequency of converge, the fitting performance in unseen data and the tracking performance in the FGNET Talking Face sequence. All results show that the 2.5D AAM can outperform both the 2D + 3D combined models and the 2D standard methods. The robust extensions to occlusion were tested on a synthetic sequence showing that the model can deal efficiently with large head rotation.  相似文献   
73.
This paper presents a mechanism for dynamic reconfiguration of component-based applications and its fault tolerance strategy. The mechanism, named generic connector, allows composing a component-based application as a set of services with no previous knowledge about the specific components that will provide some services. The components will be selected at runtime. The objective of this work is to offer a mechanism that tries to satisfy every invocation under its responsibility and makes failures as transparent as possible. It is an important tool to compose applications through the reuse of existing components because it frees the programmer from the task of searching components in order to use them and, also, from solving some types of failures.  相似文献   
74.
This paper presents a quadratic boost converter using a single quasi-resonant network to reach soft commutation. A resonant inductor, a resonant capacitor, and an auxiliary switch form the resonant network and the main switch operates in a zero-current-switching way. A complete analysis of this converter is presented. According to the simulation and experimental results, this quadratic boost converter provides a larger conversion ratio than that provided by the conventional boost converter (for a given duty ratio D), and presents optimum performance, which operates with soft-switch commutation using a single resonant network.  相似文献   
75.
76.
Debate concerning the appropriate treatment of ruptures of the Achilles tendon still continues. Conservative treatment can be associated with a high incidence of re-rupture and with relative weakness and lengthening of the triceps surae but with low costs. Surgical treatment contributes to a much lower incidence of re-rupture but can be associated with significant complications as well as with time loss and high costs of hospitalization. Subcutaneous reconstruction combines the advantages of surgical and non-surgical management. Operating with local anaesthesia reduces hospitalization time and operative costs; there are also almost no contraindications for the operation. The functional results in 36 patients operated on in this way are encouraging.  相似文献   
77.
The hyperphosphorylation of microtubule‐associated protein tau (tau) in the hippocampus can be caused by central and peripheral insulin resistance and these alterations are related to the development of tauopathies, such as Alzheimer's disease. In this study, we used a high‐fat diet to induce obesity and insulin resistance in adult Swiss mice and checked whether supplementation with Myrciaria jaboticaba berry peel for 10 weeks could improve insulin sensitivity, learning/memory performance, and prevent tau phosphorylation in the hippocampus. Furthermore, adipocytokines, inflammatory markers, and oxidative stress were assessed. Myrciaria jaboticaba peel has phenolic compounds (e.g., cyanidin, ellagic acid), dietary fiber and carotenoids, which contribute to great antioxidant capacity. Supplementation of the high‐fat diet with 4% M. jaboticaba peel prevented fat weight gain and reduced peripheral insulin resistance. The treated group also showed lower tau phosphorylation in the hippocampus corroborating better learning/memory performance in the Morris water maze test. Maintenance of neuronal viability, lower levels of hippocampal inflammatory markers, and improved brain antioxidant defenses were also related to the consumption of M. jaboticaba peel. These findings contribute to a better understanding of how a high‐fat diet supplemented with jaboticaba berry peel counteracts the impairment of cognitive functions caused by high‐fat diet intake and diet‐induced insulin resistance.  相似文献   
78.
This study determined the compromised acceptance threshold (CAT) and rejection threshold (RT) of Mentha piperita L. essential oil (MPEO) in cajá, guava and mango juices. The MPEO concentrations below the RT values were evaluated alone or combined with mild heat treatment (MHT; 54 °C) to inactivate ≥5-log10 of Escherichia coli O157:H7 and Salmonella Enteritidis PT 4 in the same juices. The CAT of MPEO varied from 0.30 to 0.32 μL mL−1, while the RT was 1.34 or 1.36 μL mL−1 in the tested juices. Only concentrations of MPEO close, or higher than the RT caused ≥5-log10 reductions in the tested pathogens in cajá, guava and mango juices. Combined with MHT, concentrations of MPEO below the RT reduced ≥5-log10 of both pathogens in juices. These findings indicate that MPEO concentrations below the RT in combination with MHT is a feasible preservation technology to ensure the safety of tropical fruit juices.  相似文献   
79.
This paper presents laboratory results of biological production of hydrogen by photoautrotophic cyanobacterium Anabaena sp. Additional hydrogen production from residual Cyanobacteria fermentation was achieved by Enterobacter aerogenes bacteria. The authors evaluated the yield of H2 production, the energy consumption and CO2 emissions and the technological bottlenecks and possible improvements of the whole energy and CO2 emission chain.The authors did not attempt to extrapolate the results to an industrial scale, but to highlight the processes that need further optimization.The experiments showed that the production of hydrogen from cyanobacteria Anabaena sp. is technically viable. The hydrogen yield for this case was 0.0114 kgH2/kgbiomass which had a rough energy consumption of 1538 MJ/MJH2 and produced 114640 gCO2/MJH2. The use of phototrophic residual cyanobacteria as a substrate in a dark-fermentation process increased the hydrogen yield by 8.1% but consumed 12.0% more of energy and produced 12.1% more of CO2 showing that although the process increased the overall efficiency of hydrogen production it was not a viable energy and CO2 emission solution. To make cyanobacteria-based biofuel production energy and environmentally relevant, efforts should be made to improve the hydrogen yield to values which are more competitive with glucose yields (0.1 kgH2/kgbiomass). This could be achieved through the use of electricity with at least 80% of renewables and eliminating the unessential processes (e.g. pre-concentration centrifugation).  相似文献   
80.
This work assessed the risk of protozoa in 10 school restaurants in Armenia (Quindío, Colombia) by analyzing the presence of Cryptosporidium spp, Giardia duodenalis, Blastocystis, and Cyclospora cayetanensis DNA in the food, water, and living and inert surfaces of school restaurants and in stools of children who ate at these restaurants. Of the 213 food, water, and surface samples, 6.6% were positive using PCR to test DNA for Blastocystis; 3.8% for Cryptosporidium spp; 0.9% for G. duodenalis; and 0% for C. cayetanensis. In 187 stool samples analyzed via microscopy from children who attended the restaurants, 40 (21.4%) were positive for Blastocystis and 21 (11.2%) were positive for Giardia spp. Via PCR, 20 (10.7%) were positive for Cryptosporidium and 0 (0%) for C. cayetanensis. A higher positivity in children's stools for Blastocystis spp was correlated with lower compliance in property conditions and for higher positivity of Giardia spp in children's stool was related to lower knowledge by food manipulators. Inspection scores can identify restaurants with higher risk for protozoa infection.  相似文献   
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