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101.
102.
The aim of the study was to examine alteration and possible application of fractal dimension, angular second moment, and correlation for quantification of structural changes in acutely inflamed tissue. Acute inflammation was induced by injection of turpentine oil into the right and left hind limb muscles of mice, whereas control animals received intramuscular saline injection. After 12 h, animals were anesthetised and treated muscles collected. The tissue was stained by hematoxylin and eosin, digital micrographs produced, enabling determination of fractal dimension of the cells, angular second moment and correlation of studied tissue. Histopathological analysis showed presence of inflammatory infiltrate and tissue damage in inflammatory group, whereas tissue structure in control group was preserved, devoid of inflammatory infiltrate. Fractal dimension of the cells, angular second moment and correlation of treated tissue in inflammatory group decreased in comparison to the control group. In this study, we were first to observe and report that fractal dimension of the cells, angular second moment, and correlation were reduced in acutely inflamed tissue, indicating loss of overall complexity of the cells in the tissue, the tissue uniformity and structure regularity. Fractal dimension, angular second moment and correlation could be useful methods for quantification of structural changes in acute inflammation.  相似文献   
103.
104.
The orbital control of geostationary satellites requires the periodic execution of manoeuvres for gravitational and solar radiation perturbation compensation. To maintain a fine control of the satellite position, it is usually sufficient to perform orbit corrections every two weeks, firing chemical thrusters. The operational load for the manoeuvre's planning and execution is usually quite low. Innovative technologies for station-keeping are available now, based on high efficiency ion thrusters, which allow a significant propellant saving. They are included in Artemis, a telecommunications satellite developed by the European Space Agency. When low acceleration ion thrusters are adopted, a near continuous orbit control is required; the resulting long firing arcs can be in conflict with some operational or technical constraints. The station-keeping planning is a critical process, since it is not based on periodic impulsive manoeuvres, but rather on quasi-continuous firings. Furthermore the orbit control should be planned more on a seasonal or a yearly cycle rather than on short weekly cycles. Since each manoeuvre is defined by its start time and duration, the total number of parameters involved in a station-keeping optimization process amounts to several tens. The presence of many variables and logical constraints makes the use of classical optimization methods quite complex. The model proposed here is based on genetic algorithms, which allows the convergence to an optimum solution through successive iterations, in which a random set of solutions is progressively selected on the basis of a factor of merit tailored to the target. This paper presents some innovative concepts for station-keeping optimization when ion propulsion is adopted for orbital control; furthermore, the general properties of genetic algorithms are discussed, together with the results obtained in the specific station-keeping application.  相似文献   
105.
The objective of this work was to evaluate the effects of γ irradiation (0, 2, 4 and 6 kGy doses), applied on frozen and packaged headed shrimps, on pathogenic Vibrio cholerae O1 and Salmonella enteritidis bacteria, as well as on some of the physical and sensory characteristics of this kind of food. The 6 kGy dose was highly efficient in inhibiting V. cholerae O1 and S. enteritidis and in decreasing lipid oxidation in shrimps compared with the nonirradiated product. Shrimp texture was not affected by any of the irradiation doses studied, but the lightness of the surface color increased in shrimps irradiated with 6 kGy compared with those irradiated with 2 kGy. Shrimps irradiated with 6 kGy showed lower overall acceptability than those irradiated with 2 kGy or were nonirradiated. The application of γ irradiation in doses up to 6 kGy on frozen and packaged headed shrimps could improve the microbiological quality of this commodity.

PRACTICAL APPLICATIONS


The use of γ irradiation has the potential to ensure safety effectively by inactivating bacteria, increasing shelf life and maintaining food quality without significant chemical changes in the food matrix. Besides, this process can be applied to frozen and packaged products. Thus, irradiation of frozen and packaged shrimps could benefit the local processing industry, which could offer the international market a high-quality product, with an additional safety treatment.  相似文献   
106.
A method of determining qualitatively and quantitatively hexamidine, dibromohexamidine, dibromopropamidine and chlorhexidine in cosmetic products by means of paired ion, reverse-phase high-performance liquid chromatography (HPLC) and ultraviolet detection (UV) at 264 nm.
Détermination de l'hexamidine, du dibromohexamidine, du dibromopropamidine et de la chlorhexidine dans les produits cosmétiques  相似文献   
107.
大青叶抗菌物质提取及抗菌效果研究   总被引:10,自引:3,他引:10  
赵良忠  王放银  段林东 《食品科学》2004,25(11):138-140
研究了用水浸提法抽提大青叶中抗菌物质的方法,并通过抑菌实验检验了对细菌和霉菌的抑菌能力。正交实验结果表明最佳抽提工艺为:料水比1:20,加热时间40min,回流温度100℃:滤纸片法抑菌实验发现:大青叶提抽浓缩液(浓缩比为5:1)对大肠杆菌及枯草杆菌的最低抑菌浓度为2.77%(ml,100ml)左右,青霉,黄曲霉为0.55%(ml/100ml)左右,金黄色葡萄球为0.055%(ml/100ml)左右。  相似文献   
108.
运用模糊聚类分析方法整编翰林桥站流量资料初探   总被引:1,自引:0,他引:1  
主要对水文资料整编采用模糊聚类分析的方法进行尝试,利用计算机定线,使得水文资料整编全面计算机化作了初步的探索,取得一定的效果。  相似文献   
109.
The decimal reduction times (D values) of Escherichia coli (American Type Culture Collection 25922) were established in a young coconut endosperm beverage, a famous local drink in the Philippines and in many tropical countries. Artificially inoculated cells were heated to 60, 70 and 80C at various heating times prior to survivor enumeration by surface plating onto pre-solidified Eosine Methylene Blue Agar. Results showed that the surviving populations significantly (P  <  0.05) decreased with increasing exposure time and temperature. The calculated D values ranged from 0.26  ±  0.01 to 0.56  ±  0.08   min. Validation of the results by establishing the thermal resistance of other E. coli isolates in the coconut beverage medium was recommended.

PRACTICAL APPLICATION


The study established the thermal inactivation rates of Escherichia coli (American Type Culture Collection 25922) in a young coconut endosperm beverage medium in various heating temperatures. The results obtained from this study may be used in the calculations of appropriate thermal process schedules for the test beverage against the test organism.  相似文献   
110.
In this study, we have investigated the stability of the antigenotoxic properties of dried of Lentinula edodes (Berk.) Singer mushroom powder stored at room and at − 20C. Mice were pretreated by gavage for 15 consecutive days with 0.6 mL/day of an aqueous extract of dried L. edodes powder prepared at 60C. On day 15, the mice were intraperitoneally injected with 50 mg/kg N-ethyl-N-nitrosourea (ENU); 3 h later, peripheral blood was withdrawn from the animals and used to evaluate DNA damage using the comet assay. The mice were sacrificed 24 h after the ENU treatment and the bone marrow used to measure the frequency of micronucleated polychromatic erythrocytes. The results indicated that storage at both room temperature and at − 20C significantly reduced the antigenotoxic effects of the mushroom powder. In addition, whereas freshly dried mushroom powder was nongenotoxic, storage of the powder at − 20C resulted in genotoxic activity ( P <  0.05). Taken together, our data indicate that constituents of L. edodes powder are altered during storage, resulting in both genotoxicity and a reduction in antigenotoxicity.  相似文献   
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