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41.
The current study delineates the development of novel gelatin–tamarind gum/carboxymethyl tamarind gum-based phase-separated films for probable skin tissue engineering applications. Polyethylene glycol was used as plasticizer. The films were characterized thoroughly using mechanical tester and impedance analyzer. Cell proliferation ability and drug release properties of the films were investigated. Mechanical studies indicated composition-dependent stress relaxation properties. Polysaccharide containing films supported better proliferation of human keratinocytes as compared to control. Drug-loaded films showed good antimicrobial properties against Escherichia coli. Analysis of the results indicated that the prepared films may be tried as matrices for skin tissue engineering.  相似文献   
42.
The current study discusses the synthesis of novel gelatin–chitosan lactate cohydrogels. Mechanical studies indicated the viscoelastic nature of the cohydrogels. The cohydrogels were predominantly elastic in nature. Inherent mechanical stability of the cohydrogels was better than the pristine gelatin hydrogel. Incorporation of chitosan lactate improved the in vitro swelling and the drug release properties of the cohydrogels. The cohydrogels showed good antimicrobial drug delivery capacity. The properties of the developed cohydrogels demonstrated that they could be used as delivery vehicles for antimicrobial drugs. Cell proliferation study suggested that the cohydrogels supported the proliferation of the human keratinocytes.  相似文献   
43.
Recognition of control chart patterns using improved selection of features   总被引:2,自引:0,他引:2  
Recognition of various control chart patterns (CCPs) can significantly reduce the diagnostic search process. Feature-based approaches can facilitate efficient pattern recognition. The full potentiality of feature-based approaches can be achieved by using the optimal set of features. In this paper, a set of seven most useful features is selected using a classification and regression tree (CART)-based systematic approach for feature selection. Based on these features, eight most commonly observed CCPs are recognized using heuristic and artificial neural network (ANN) techniques. Extensive performance evaluation of the two types of recognizers reveals that both these recognizers result in higher recognition accuracy than the earlier reported feature-based recognizers. In this work, various features are extracted from the control chart plot of actual process data in such a way that their values become independent of the process mean and standard deviation. Thus, the developed feature-based CCP recognizers can be applicable to any general process.  相似文献   
44.
Gauri  Samla  Gan  Kok Beng  Then  Sue-Mian 《Microsystem Technologies》2019,25(4):1379-1385
Microsystem Technologies - The conceptual simulation study of DNA extraction and separation from salivary fluid sample are mainly divided into two parts. The initial study covered microfluidic...  相似文献   
45.
A rapid and cost-effective technique for identification of microorganisms was explored using fluorescence microscopy and image analysis, and classification was done with trained neural network. The microorganisms used in this study are Bacillus thuringiensis (C399), Escherichia coli K12 (ATCC 10798), Lactobacillus brevis (LJH240), Listeria innocua (C366), and Staphylococcus epidermis (LJH343). After staining the microorganisms with fluorescent dyes [diamidino-2-phenyl-indole and acridine orange (AO)], images of the microorganisms were captured using a digital camera attached to a light microscope. Geometrical, optical, and textural features were extracted from the images using image analysis. Parameters extracted from images of microorganisms stained with AO gave better results for classification of the microorganisms. From these parameters, the best identification parameters that could classify the microorganisms with higher accuracy were selected using a probabilistic neural network (PNN). PNN was then used to classify the microorganisms with a 100% accuracy using nine identification parameters. These parameters are: 45° run length non-uniformity, width, shape factor, horizontal run length non-uniformity, mean gray level intensity, ten percentile values of the gray level histogram, 99 percentile values of the gray level histogram, sum entropy, and entropy. When the five microorganisms were mixed together then, also the PNN could classify the microorganisms with 100% accuracy using these nine parameters.  相似文献   
46.
The identification of various unnatural patterns that are usually exhibited in quality control charts leads to more focussed diagnosis and, thereby, significantly minimises the effort towards effective troubleshooting. Feature-based control chart pattern (CCP) recognition systems have the advantage that the users can easily understand how a particular pattern is identified. Pham and Wani have presented a feature-based heuristic approach for CCP recognition which can differentiate six types of CCPs, based on the extraction of nine shape features. The extraction of some of these features requires users’ inputs and, thus, this CCP recognition system is not truly automated. Moreover, many real-life situations require detection of all of the eight basic CCPs, including stratification and systematic patterns. The extraction of the features after the scaling of pattern data into an (0, 1) interval can ensure that the magnitudes of the features are independent of the mean and standard deviation of the underlying process. But the distinction between normal and stratification patterns is lost when the pattern data are scaled. A CCP recogniser that will identify a stratification pattern, therefore, needs to be developed using unscaled pattern data. In this paper, potentially useful 32 features, the extraction of which do not require users’ inputs of any form, are proposed. The magnitudes of these features are independent of the process mean and are considerably insensitive to changes in the process standard deviation. An easy mechanism for the determination of the optimal set of features and a heuristic is also presented. Sensitivity studies on the performance of the heuristic show that it is robust against the estimation error of the process mean and is reasonably robust against the estimation error of the process standard deviation. Thus, it has enough potential for use in real-time process control applications.  相似文献   
47.
Factors believed to have contributed to the reemergence of kernicterus in the United States during the 1990's are discussed: these include decreased concern about toxicity of bilirubin in term and near-term infants, increased prevalence of breastfeeding, and increasingly shortened postnatal hospital stays. The rationale for a universal predischarge bilirubin measurement at the time of the routine predischarge metabolic screen is presented: the hour-specific level of bilirubin at discharge, plotted on an Hour-Specific Bilirubin Nomogram, improves prediction of risk of excessive jaundice postdischarge and facilitates safe, cost-effective follow-up. This minimizes repeat bilirubin measurements and maximizes recognition of confounding variables and risk of hyperbilirubinemia so that timely, minimally invasive, preventive therapy can be instituted if needed.  相似文献   
48.
For nearly 50 years a relatively stable Indus Water Treaty (IWT) moderated competition for the Indus water between Pakistan and India. Rising demand for water in each nation could unsettle this stable relationship, as foreshadowed by the involvement of a third party during 2005–2007 for the first time in the treaty's history. This paper discusses Pakistan and India's experience in the context of other international shared rivers. For the benefit of their people, Pakistan and India could coordinate unilateral development and resolve issues rather than defer them.  相似文献   
49.
Food packaging represents a large fraction of municipal solid waste and contributes to the expansion of landfill sites. Commonly used expanded polystyrene packaging trays are difficult to biodegrade. A potential alternative to this product is biodegradable/edible soy‐based packaging trays. Soy‐based tray formulations and fabrications were examined. Mechanical properties from a three‐point flexural test were used as the basis for process/ingredient selection. Soy protein isolate, glycerol and gellan gum or κ‐carrageenan were found suitable. Regression models relating ingredient levels to mechanical properties were obtained and process conditions were optimized. The optimum process conditions for gellan gum‐based trays were a heating temperature of 60°C, a heating time of 1min and a refrigeration setting time of 20min. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
50.
BACKGROUND AND STUDY AIMS: To evaluate the utility of a suspension of galactose microparticles available as SHU508 A (Levovist) as a contrast agent during endoscopic ultrasonography (EUS). MATERIALS AND METHODS: Three sets of experiments were performed on three 20-25 kg swine (Sus scrofa) under general anesthesia. Upper EUS was performed with an echo endoscope with color Doppler capability (Pentax FG-32 UA). The celiac artery, superior mesenteric artery, aorta, portal vein, pancreas, and gastrointestinal wall were imaged by EUS. Multiple intravenous bolus injections of 400 mg/ml of SHU508 A were made, and their effect on color Doppler and gray-scale imaging during EUS was studied. RESULTS: After contrast injection there was a significant, visually noticeable enhancement of the color Doppler signals from the celiac artery, superior mesenteric artery, and portal vein. Vessels with weak to no color Doppler signals before injection of SHU508 A--for example, the celiac artery and superior mesenteric artery--were observed to have strong color signals after injection. The effect of SHU508 A on color Doppler imaging was easily appreciated subjectively without the need for complex quantitative measurements. No visually noticeable color Doppler enhancement was seen in vessels such as the aorta that had a very pronounced color Doppler signal even prior to the injection of contrast. Movement of particulate matter was seen in the portal vein on the gray scale. CONCLUSION: Intravenous SHU508 A as a contrast agent significantly enhances color Doppler signals during EUS. Vascualar contrast of this sort could potentially have a significant role in improving the accuracy of EUS in diagnosing malignant vascular invasion, the detection of occult pancreatic neoplasms, and the diagnosis of vascular thrombosis.  相似文献   
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