Preparation,Characterization and Assessment of the Novel Gelatin–tamarind Gum/Carboxymethyl Tamarind Gum-Based Phase-Separated Films for Skin Tissue Engineering Applications

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.     

Synthesis and Assessment of Novel Gelatin–Chitosan Lactate Cohydrogels for Controlled Delivery and Tissue Engineering Applications

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.     

Recognition of control chart patterns using improved selection of features

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.     

Evaluating the protective role of carrier microparticles in preserving protein secondary structure within electrospun meshes

Direct incorporation of proteins into electrospun meshes using approaches such as blend electrospinning can promote adverse interactions with hydrophobic polymers, organic solvents and high voltage, potentially leading to loss of protein activity. However, pre-encapsulation within a protective carrier phase can preserve protein conformation by avoiding exposure to harsh processing conditions. In this study, bovine serum albumin (BSA) was loaded within cellulose microparticles (MPs) and the BSA-loaded MPs were dispersed in a solution of poly(ethylene oxide) (PEO). Particle-mesh composites were created using a sacrificial fiber/co-electrospinning approach in which the BSA/MP/PEO solution was simultaneously electrospun against a poly(caprolactone) (PCL) solution. Post-fabrication, sacrificial PEO fibers were selectively dissolved by treatment with ethanol. Microscopy, weight loss analysis and FTIR spectroscopy together confirmed selective dissolution of PEO fibers and the retention of BSA-loaded MPs within the PCL network without significant loss of either the MPs or the protein. Circular dichroism spectroscopy and intrinsic fluorescence measurements on BSA extracted from the co-electrospun meshes indicated minimal disruption to secondary structure, although partial sheet induction was observed. In contrast, direct exposure of BSA to four commonly used electrospinning solvents resulted in a large decrease in helical content and significant induction of sheets, revealing significant changes to the secondary structure. In summary, our results demonstrate the protective role of MPs in minimizing adverse effects of electrospinning on the secondary structure of incorporated protein.     

Simulation of DNA extraction and separation from salivary fluid by superparamagnetic beads and electromagnetic field in microfluidic platform

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...     

Effectiveness of heparin in preventing thrombin generation and thrombin activity in patients undergoing coronary intervention

BACKGROUND: Thrombus is important in the pathophysiology of several complications of angioplasty, including abrupt closure and restenosis. Levels of prothrombin fragment F1.2 and fibrinopeptide A reflect thrombin generation and activity. The effect of angioplasty on levels of these markers is unclear. METHODS: Patients undergoing either balloon angioplasty (n = 30) or directional atherectomy (n = 9) were treated with heparin to maintain an activated clotting time of >300 seconds. Levels of F1.2, fibrinopeptide A, and thrombin-antithrombin complex were measured in the coronary sinus and coronary artery before and after intervention. Angiograms were reviewed for lesion morphologic characteristics and dissection. RESULTS: There was no evidence for thrombin generation or increased thrombin activity after angioplasty regardless of lesion morphologic characteristics, dissection, type of intervention, or blood sampling site. In fact, coronary sinus concentrations of F1.2 decreased after intervention (median 0.31 nmol/L; 25th percentile 0.26 nmol/L, 75th percentile 0.37 nmol/L) before intervention to 0.23 nmol/L (25th percentile 0.19 nmol/L, 75th percentile 0.34 nmol/L) after intervention (P =.002). CONCLUSIONS: Angioplasty performed in the presence of adequate heparin inhibited thrombin even when there was complex lesion morphology or dissection. These data suggest that heparin provides satisfactory thrombin inhibition during routine angioplasty.     

Rapid Detection of Microorganisms Using Image Processing Parameters and Neural Network

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.     

A study on the various features for effective control chart pattern recognition

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.     

Water sharing between India and Pakistan: a critical evaluation of the Indus Water Treaty

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.     

Formulation and process conditions for biodegradable/edible soy‐based packaging trays

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.