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21.
This paper presents two novel directional patterns, a Maximum Response-based Directional Texture Pattern (MRDTP) and a Maximum Response-based Directional Number Pattern (MRDNP), for recognizing the facial emotions in constrained as well as unconstrained situations. The intensity information obtained from the maximum of the edge responses, after applying eight Kirsch masks, is used for the calculation of facial features in MRDTP. In MRDNP, instead of intensity information, the direction number of the maximum response is used. After dividing MRDNP and MRDTP code images into grids, feature vectors are created from the concatenated histograms obtained from the grids. This paper also proposes an effective Generalized Supervised Dimension Reduction System (GSDRS) and uses Extreme Learning Machine with Radial Basis Function (ELM-RBF) classifier for rapid and efficient classification of emotions. Both the proposed patterns are more effective than the existing ones in removing random noise and providing good structural information using prominent edges which help to achieve high classification accuracy when tested with seven datasets.  相似文献   
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过氧化氢酶催化过氧化氢分解形成水和氧,主要作用是保护细胞免受活性氧(ROS)的损伤,尽管其在工业上被广泛使用,但因热稳定的不足限制了它的使用前景。本研究以Bacillus pumilus ML413来源的血红素过氧化氢酶(Kat X2)为研究对象,采用定点突变技术提高其热稳定性及催化效率。利用Po PMu Si C algorithm软件计算并预测了其潜在突变位点的折叠自由能,根据预测的结果,选择了其中自由能最低的3个位点(K117V, K117I和K117M)进行突变。结果发现,对K117位点进行突变,可以有效提高Kat X2的热稳定性,突变体K117V在60℃下半衰期比野生型Kat X2提高38 min,催化效率较突变前提高31.7%。根据结构分析发现,该点突变并未改变Kat X2的二级结构。突变体K117V具有良好的工业应用潜力。  相似文献   
23.
High-power superluminescent diodes   总被引:12,自引:0,他引:12  
By inclining the active stripe of a planar AlGaAs double heterojunction structure by 5° with respect to the facets, reflection feedback has been eliminated and high-power superluminescent diodes emitting 28 mW with less than 5% spectral modulation have been obtained  相似文献   
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Y chromosome molecular analysis was performed using the STS-PCR technique in 50 patients with oligozoospermia. Microdeletions of interval 6 of the Y chromosome were detected in seven patients, in six of whom subinterval E was affected. All patients retained the RBM1 and DAZ genes, while in one deletion involved the SPGY gene. The size of the deletion was not apparently related to the severity of the disease. These results suggest the presence of an oligozoospermia critical region on the Y chromosome within subinterval E of interval 6.  相似文献   
25.
This study investigates the effect of chemical composition and microsegregation on the bainitic transformation of high Si cast steels at two different austempering temperatures. The advance of the bainite precipitation as a function of time and temperature was monitored through measurements of the amount of retained austenite by X-ray diffraction, the evolution of hardness and microstructural characterization. The results showed that the bainitic transformation starts preferentially at zones with lower contents of alloying elements but later covers the entire matrix. The austempering heat treatments resulted in an apparently homogeneous bainitic microstructure throughout the entire matrix after a short period of time. The results encourage the continuation of the development of high Si steels suitable to produce carbide-free austempered cast parts.  相似文献   
26.
Cryogenic milling process is more effective in generating nano- and micro-size particles than conventional high-energy mechanical milling in terms of their size and processing time needed as the cryogenic temperature lowers the activation energy for elastic fracture and minimizes agglomeration among particles. Following the previous success in fabricating uniform chalcopyrite CuInSe2 nanoparticles using the cryogenic milling process, this study has deposited CuInS2 thin films through a particle-based, non-vacuum sequential process that includes the preparation of precursor particles using a cryogenic milling process. The paste formulated with the particles was coated on Mo-deposited glass substrate and subsequently sulfurized under S/H2/Ar atmosphere. The chalcopyrite CuInS2 thin films were successfully made after sulfurization at the substrate temperature of 550 °C in 30 min. Optimization of pre-baking step prior to sulfurization was critical in achieving dense morphology of the films and the residual oxygen in the nanoparticles was efficiently removed by its reduction reaction with H2 during the sulfurization process. While the cryogenic milling process can effectively produce particles in a short period of time, preventing agglomeration, further study is necessary to understand the effect of structural and morphological properties of the starting materials on the final outcome from the cryogenic milling process.  相似文献   
27.
During the past decade, particular attention has been focused on treatment of bladder cancer patients with the bacterial agent bacillus Calmette-Guérin (BCG). In these studies, bladder cancer patients were instilled with BCG (75 mg/50 ml) once per week for 6 weeks, 1-2 weeks following trans-urethral resection of the bladder. Cystoscopy was performed after 6 weeks and, unless tumor progression was present, monthly treatments were given for 1 year. Blood was drawn 2 h after the last instillation, and monocytes were isolated (5 x 10(6) cells/ml) and treated, or not, with lipopolysaccharide (LPS) (20 microgram/ml) for tumor necrosis factor alpha (TNF alpha), interleukin-1 alpha (IL-1 alpha) and interleukin-6 (IL-6) release. The levels of monokines were determined by a monokine-specific enzyme-linked immunosorbent assay. Our results clearly show that, after 18 h incubation, macrophages from BCG-treated bladder cancer patients produced from 2.8- to 1.9-fold and from 2.0- to 1.3-fold greater amounts of TNF alpha and IL-1 alpha respectively, compared to macrophages from healthy controls, 5-fold higher than bladder cancer patients not treated with BCG. IL-6 was not affected. In another set of experiments macrophages (5 x 10(6) cells/ml) from healthy subjects were pretreated, or not, with BCG (100 micrograms/ml) overnight and treated, or not, with LPS 20 microgram/ml alone and in combination with interleukin-1 receptor antagonist (IL-1ra) 250 ng/ml. Macrophages treated with BCG had a strong stimulatory effect on IL-1 alpha release (9.45 ng/ml) while LPS was less effective (3.59 ng/ml). The combination of BCG plus LPS produced an additive effect on IL-1 alpha release (13.71 ng/ml) compared to the effect of the compound alone. The addition of IL-1ra (250 ng/ml) to BCG was not effective, while when IL-1ra was added to BCG plus LPS only a partial inhibition of IL-1 alpha release was found (9.83 ng/ml), compared to BCG plus LPS without IL-1ra (13.71 ng/ml). These effects seem to be related to the inhibition of IL-1 alpha stimulated with LPS, but not BCG. The priming effect of BCG exerted on LPS-stimulated monocyte production of TNF alpha and IL-1 alpha from bladder cancer patients led us to study the possible modulation of fibrinogen and C-reactive protein in the serum of BCG-treated cancer patients. The plasma levels of fibrinogen and C-reactive protein were higher (approximately twice) in BCG-treated patients compared to values obtained in untreated patients or healthy controls. We conclude that the beneficial immunotherapeutic effects of BCG in bladder cancer patients are related to its capacity to prime macrophages to enhance the release of TNF alpha and IL-1 alpha, but not IL-6 in response to physiological secondary stimuli, or through the direct stimulation of BCG on IL-1 alpha or TNF alpha, which are directly involved in the killing of cancer cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
28.
The modal reflectivity of an angled facet has been calculated for index-guided devices when the fundamental mode excites various higher order modes at the facet. The calculations were carried out for waveguide widths ranging from 2 to 20 μm for various lateral index steps and at wavelengths of 834, 1300, and 1550 nm. Plots from these calculations can be used to determine the appropriate facet angles to obtain a given modal reflectivity and optimize the design of optical amplifiers and superluminescent diodes  相似文献   
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