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This study deals with effect of various concentrations of chitosan and material parameters on hemostatic properties of the woven and nonwoven dressings. The woven and nonwoven dressings are compared on efficacy on hemostasis. In addition to the studies on bio-polymer and minerals, 1% and 2% of chitosan particle dissolved solution were applied in both plain gauze and spunlace fabrics of cotton and viscose. The hemostatic efficacy and wound dressing suitability were analyzed and based on the results, the 2% chitosan viscose spunlace material was chosen due to its best performance for developing secondary layer for composite wound dressing.

Knot configurations serve as the foundation for postoperative tissue repair. Loosening surgical knots during or after tying might lead to an unsuccessful suture and compromise the outcome. This investigation was car­ried out to study the mechanical properties of knotted silk sutures that are made from braided structures with three different diameters. A maximum tensile strength (33.24 N) and minimum breaking elongation (15%) of dry suture, maximum tensile strength (22.6 N) and minimum breaking elongation (13.6%) of wet suture were achieved with five throws and a diameter of 0.3 mm with surgeon’s square knot.

Abstract Jute hairy caterpillar, Spilosoma (=Spilarctia) obliqua (Walker) (Arctiidae: Lepidoptera), is an irregular and polyphagous insect pest that occurs all over India. A severe natural viral epizootic was observed in the field population of S. obliqua in jute. The virus was characterized as Spilosoma obliqua nucleopolyhedrovirus (SpobNPV NBAIR1) based on morphological, biological, and molecular characterization. Under scanning and transmission electron microscopy (SEM and TEM), the occlusion bodies (OBs) of SpobNPV NBAIR1 appeared as both tetrahedral and triangular with the size ranged from 1.04-1.72 μm. The results on the bioassay studies revealed that the lowest LC50 value of 2.93 OBs/mm2 by leaf disc bioassay against the second instar S. obliqua showed its high virulence. The identity of SpobNPV was further confirmed by the amplification of polyhedrin gene (NCBI GenBank accession no. MK288145). Eleven species of lepidopteran insects, viz., Spodoptera litura, S. exigua, S. frugiperda, Helicoverpa armigera, Plutella xylostella, Amsacta albistriga, Maruca vitrata, Trichoplusia ni, Pieris brassicae, Agrotis ipsilon, and Bombyx mori, were not susceptible to the infection with SpobNPV NBAIR1. Field experiments on jute crop revealed 68.92, 78.59, and 93.16% reduction in larval population of S. obliqua at 3, 4, and 7 days post spray of SpobNPV NBAIR1 (1.5 × 1012 OBs/ha at 2 ml/l), respectively. The present study is a renewed effort in the management of S. obliqua by the new strain of SpobNPV NBAIR1.

The Peristaltic transport of a viscous fluid in a channel with suction and injection is investigated in the present work. The mathematical modeling has been carried out under long wavelength and low Reynolds number approximation. The analytical solution for velocity field pressure gradient, frictional force and stream function in the wave frame of reference is obtained. The pressure rise and frictional force over one wavelength are obtained. The effect of different parameters on pumping characteristics and frictional forces is discussed graphically. It is observed that pressure rise decreases with increasing permeability parameter and increases with increasing amplitude. It is also observed that for various values of suction parameter k, the pumping curves coincide at a point in the first quadrant due to the suction or injection in the channel. The frictional forces illustrate the opposite behavior compared to pressure rise. The trapping phenomenon for different parameters is presented graphically. Keywords: Peristaltic transport, Suction and injection, Permeability parameter, Channel

This study investigates the optimization of process parameters for coating silk sutures with Acanthus ilicifolius leaf extract. The increasing awareness of surgical site infections is a critical concern associated with the use of sutures in medical procedure undertaking. Our study aimed to assess the impact of three crucial coating factors, namely extract content, temperature, and duration, on the mechanical and antibacterial characteristics of silk sutures braided together. Through Box–Behnken design, in conjunction with the response surface approach, we conducted a thorough analysis to refine the model. The result showed that extract concentration directly influences both antimicrobial activity and elongation, while temperature and time primarily affect tensile strength and bending stiffness. To achieve the maximum tensile strength, minimum breaking elongation, minimum bending stiffness, and lower friction, all while maintaining the important antimicrobial efficacy of the sutures, this study emphasizes the use of response surface methodology in optimizing coating parameters for A. ilicifolius leaf extract on silk sutures. The response models are developed on the complex relationships between these parameters and the properties of the sutures. [ABSTRACT FROM AUTHOR]

This study was designed to develop matrix type of transdermal‐controlled delivery system for zidovudine using Eudragit L100 by varying the amounts of drug in addition to polyethylene glycol as a plasticizer and Tween 80® as a penetration enhancer. Transparent smooth and flexible films were characterized for weight, thickness uniformity, and drug content. Drug interactions with the polymer films were studied by differential scanning calorimetry, whereas X‐ray diffraction was used to understand the drug polymorphism in the films. The in vitrodrug release experiments were performed in phosphate buffer using the Keshary‐Chien diffusion cell. Variations of drug release profiles were analyzed using the Ritger and Peppas empirical equation to describe the type of release mechanism. The exponent nvalues of the equation varied over the wide range of 0.75–2.23, suggesting non‐Fickian to super Case‐II type of diffusion transport. Statistical analyses of release data performed by the analysis of variance (ANOVA) method indicated significant differences within experimental measurements. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Thermoresponsive microspheres of gellan gum‐poly(N‐isopropylacrylamide), i.e., GG‐P(NIPAAm) semi‐interpenetrating polymer networks (semi‐IPNs) have been prepared by ionic crosslinking and used to study the controlled release (CR) of atenolol (ATL), an antihypertensive drug. Interaction of the drug with polymers was studied by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) was used to confirm the polymorphism and molecular level dispersion of ATL. Scanning electron microscopy (SEM) indicated spherical nature and smooth surfaces of the microspheres with some debris attached on their surfaces. Mean particle size measured by laser light diffraction ranged between 34 and 76 μm. Equilibrium swelling performed at 25°C and 37°C in pH 7.4 phosphate buffer exhibited thermoresponsive nature of the polymers. In vitrodrug release performed at 25°C and 37°C indicated temperature‐dependency of ATL release, which was extended up to 12 h. In vitrorelease profiles at both the temperatures confirmed thermoresponsive nature of the polymers giving pulsatile trends. The % cumulative release data have been fitted to an empirical equation to estimate transport parameters and to understand the nature of drug release. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

Naturally available carbohydrate polymers such as methylcellulose (MC) and gelatin (Ge) have been widely studied in the previous literature for controlled release (CR) applications. In this study, methyl cellulose‐g‐acrylamide/gelatin (MC‐g‐AAm/Ge) microspheres were prepared by water‐in‐oil (W/O) emulsion method and crosslinked with glutaraldehyde to encapsulate with nifedipine (NFD), an antihypertensive drug. The microspheres prepared were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and laser particle size analyzer. DSC thermograms of NFD‐loaded AAm‐MC/Gel microspheres confirmed the molecular level distribution of NFD in the matrix. SEM indicated the formation of spherical particles. Swelling experiments supported the drug diffusion characteristics and release data of the matrices. Cumulative release data were analyzed using an empirical equation to understand the nature of transport of drug through the matrices. Controlled release characteristics of the matrices for NFD were investigated in pH 7.4 media. Drug was released in a controlled manner up to 12 h. Particle size and size distribution of the microspheres as studied by laser light diffraction particle size analyzer indicated their sizes to be around 120 μm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

Poly(methylmethacrylate)‐poly(vinyl pyrrolidone) (PMMA‐PVP) microspheres loaded with cefadroxil (water‐soluble) and indomethacin (water‐insoluble) drugs have been prepared by the dispersion polymerization technique using PVP as a steric stabilizer. Microspheres have been characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and X‐ray diffraction (X‐RD) studies. DSC studies indicated coating of PVP onto PMMA microspheres. SEM suggested the formation of microspheres in the size of around 5 μm. X‐RD confirmed that drug has been highly dispersed in polymer particles. Higher encapsulation efficiency of up to 84% was achieved for hydrophobic drug, indomethacin than for hydrophilic cefadroxil. In vitro release studies performed in pH 7.4 phosphate buffer saline indicated that release of indomethacin was controlled up to 12 h, whereas cefadroxil was released in a controlled manner up to 10 h. During in vitro release, properties of both the drugs remained unaltered. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1860–1865, 2007 [ABSTRACT FROM AUTHOR]

In the present study, the dynamic performance of the sandwich plate with magneto rheological elastomer (MRE) as the core layer and tapered laminated composite plates as the face layers is investigated. Various MRE tapered laminated composite sandwich plate models are formulated by dropping-off the plies longitudinally in top and bottom composite layers to yield tapered plates as the face layers and uniform MRE layer as the core layer. The governing equations of motion of tapered composite MRE sandwich plates are derived using classical laminated plate theory and solved numerically. Further, silicon based MRE is being fabricated and tested to obtain the shear and loss moduli using MR rheometer. The efficacy of the finite element formulation is validated by carrying out experiments on the various prototypes of tapered composite silicon based MRE sandwich plates and comparing the results in terms of natural frequencies obtained at various magnetic fields with those obtained numerically and with available literature. Also, the effects of magnetic field, taper angle of the top and bottom layers, aspect ratio, ply orientations and various end conditions on the various dynamic properties of tapered laminated composite MRE sandwich plate are investigated. Further, the transverse vibration responses of three different tapered composite MRE based sandwich plates under harmonic force excitation are analyzed at various magnetic fields. [ABSTRACT FROM AUTHOR]

An increase in demand for natural fiber has created a good opportunity for the – new emerging fiber like bhindi, the ‘fiber from waste plant,’ into the production of value-added textiles and in different applications. This paper envisages a customized blending process of bhindi and jute fibers for developing durable blended yarns, fabrics, and suitable home textiles products; additionally, the effect of blending in terms of physical and esthetic properties of fabric has been investigated. Five types of yarns (100% bhindi, 75:25 bhindi/Jute, 50:50 bhindi/jute, 25:75 bhindi/jute, and 100% jute) have been prepared under identical processing condition and subsequently, blended fabrics are developed. Further based on the survey results the suitable home textiles products are developed. Effects of jute fiber blending on physical and esthetic properties of bhindi/jute-blended fabrics have been examined and subsequently, comparative analysis with 100% bhindi (control) fabric has been carried out. It was found that bhindi:Jute-blended fabrics have increased in strength and flexible property and have an increase in air permeability and absorbency property. Different products were developed from five different fabrics and the majority of respondents found the products as suitable for different home textiles uses.

This paper describes the application of Musa acuminata leaf methanol extract on cellulose fabrics. Musa acuminata is a banana species. It is a popular edible fruit consumed worldwide. Musa acuminata leaf methanol extract was prepared, and Fourier Transform Infrared Spectroscopy was performed to analyze the extracted solution using 0.1% NaOH. The methanol extract in three different concentrations, viz., 3%, 5%, and 7%, was applied on cotton fabrics using padding mangle at room temperature, 40°C, and 50°C, respectively. After application of the methanol extract, antibacterial property of the fabric was tested both qualitatively by a zone of inhibition (AATCC-147) and quantitatively by reduction of bacteria evaluated in percent (AATCC-100). Presence of gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacteria were studied following the AATCC standards. The results reveal that the methanol extract from Musa acuminata leaf, an economic resource, can be applied to medical textile fabrics to impart antibacterial action and UV protection.

The Atomic Minerals Directorate for Exploration and Research (AMD) has conducted high-resolution airborne gamma ray spectrometer (AGRS), magnetometer and time domain electromagnetic (TDEM) surveys for uranium exploration, along the northern margins of Cuddapah Basin. The survey area includes well known uranium deposits such as Lambapur-Peddagattu, Chitrial and Koppunuru. The AGRS data collected for uranium exploration is utilised for estimating the average absorbed rates in air due to radio-elemental (potassium in %, uranium and thorium in ppm) distribution over these known deposit areas. Further, portable gamma ray spectrometer (PGRS) was used to acquire data over two nearby locations one from Lambapur deposit, and the other from known anomalous zone and subsequently average gamma dose rates were estimated. Representative in-situ rock samples were also collected from these two areas and subjected to radio-elemental concentration analysis by gamma ray spectrometer (GRS) in the laboratory and then dose rates were estimated. Analyses of these three sets of results complement one another, thereby providing a comprehensive picture of the radiation environment over these deposits. The average absorbed area wise dose rate level is estimated to be 130 ± 47 nGy h -1 in Lambapur-Peddagattu, 186 ± 77 nGy h -1 in Chitrial and 63 ± 22 nGy h -1 in Koppunuru. The obtained average dose levels are found to be higher than the world average value of 54 nGy h -1 . The gamma absorbed dose rates in nGy h -1 were converted to annual effective dose rates in mSv y -1 as proposed by the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR). The annual average effective dose rates for the entire surveyed area is 0.12 mSv y -1 , which is much lower than the recommended limit of 1 mSv y -1 by International Commission on Radiation protection (ICRP). It may be ascertained here that the present study establishes a reference data set (baseline) in these areas to assess any changes in gamma radiation levels due to mining and milling activities in future., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Surgical angioplasty for ostial stenosis of the major coronary arteries is a well-established treatment modality. Management of discrete stenoses of distal coronary arteries in the presence of mild proximal disease is a challenging task. Percutaneous intervention or grafting beyond the diseased segment may be limited by size of the target vessel, whereas endarterectomy followed by graft placement may result in graft occlusion due to competitive native flow. Patch angioplasty with or without endarterectomy is an effective option in this setting, which can be performed without cardiopulmonary bypass in the appropriate group of patients. A patient with triple vessel coronary artery disease and a discrete lesion in the posterior descending artery underwent off-pump endarterectomy with vein patch angioplasty in combination with bypass grafting to left anterior descending and obtuse marginal arteries. Operative technique and intraoperative strategies are discussed.

Roller pumps are widely used for cardiopulmonary bypass in developing nations by virtue of proven safety during several years of institutional use and cost effectiveness. However, careful adjustment of roller occlusion is needed because they are known to cause spallation, tubing wear, and the occasional incident of rupture of tubing in the extracorporeal circuit. Rupture of polyvinylchloride tubing in the pump raceway during repair of a ventricular septal defect in a 4-year-old child is discussed. The event was managed by exclusion and replacement of the defective tubing during a short period of arrest. Use of an inappropriate boot pump and failure to detect its inclusion in the bypass circuit was a significant departure from protocol. However, because occlusion settings and duration of perfusion were within acceptable limits, a manufacturing flaw could also have contributed to tubing failure, and the event may or may not have been averted by the use of larger tubing. In conclusion, this incident reiterates the need for adherence to established protocol during assembly of the pump and draws attention to the fact that tubing integrity is not a guarantee and vigilance is warranted to handle its failure.

Congenital heart disease is related to events occurring in the embryonal stage, while rheumatic heart disease is a sequela of immune-mediated damage following streptococcal infection. We report an unusual association of multiple ventricular septal defects and severe pulmonary arterial hypertension with rheumatic mitral stenosis in a 7-year-old girl. This case highlights the need for careful examination for coexisting rheumatic disease in late presentations of congenital heart disease.