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In this paper, we define the [Formula: see text]th Vandermonde determinant and determine the coefficient bounds for the second- and third-order Vandermonde determinant for a Sakaguchi type function [Formula: see text] and [Formula: see text] which map open unit disc onto the region bounded by Limaçon [Formula: see text] Sharp upper bounds are obtained for second-order Vandermonde determinant.

In this paper, we introduce and define a new subclass of harmonic univalent functions involving generalized hypergeometric functions which are sense-preserving in the open unit disc. Further we obtain the coefficient bounds, extreme points, convex combination, growth bounds, distortion bounds and integral operator for this class.

Background: Superficial mycoses are common worldwide. Dermatophytic infections can greatly affect quality of life. Several newer antimycotic agents, have been reported effective and safe. Hence this study was planned to analyse effectiveness as well as cost effectiveness of these treatments.Methods: It were a prospective, randomized, parallel, open label, comparative study. Fifty patients were included in the study and divided into 2 groups. They were randomized to receive either oral terbinafine 250 mg or itraconazole 100 mg once daily for 4 weeks. Scaling, erythema and pruritus were rated as clinical score 0 to 3: 0 - absent, 1 - mild, 2 - moderate, and 3 - severe for the above three target symptoms. Total symptom score was assessed. Pruritus was also graded on visual analogue scale (VAS). Mycological cure was assessed by skin scraping with KOH mounts and fungal culture. Clinical efficacy scoring and VAS were assessed before the study and at each follow up visit at 2 and 4 weeks. Patients were followed up for another 4 weeks after completion of the treatment.Results: There was highly significant decrease p

The ultrasonic degradation of poly(vinyl alcohol) was investigated at different pHs of the solvent, in different water/solvent binary mixtures, and at different polymer concentrations. The samples were analyzed with gel permeation chromatography. The degradation rate coefficients were determined with a continuous distribution model. A higher degradation rate was obtained at pH extremes, in better solvents, and at lower polymer concentrations. The results are explained and discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4888–4892, 2006

The photodegradation of poly(vinyl alcohol) (PVA) in aqueous solution was investigated under UV exposure and pulsed-laser irradiation. The degradation under UV exposure was studied at different pH values and with the addition of potassium chloride and potassium dichromate. The pulsed- laser degradation of PVA was investigated with a Nd : YAG laser, operating at a wavelength of 266 nm with about 6-ns pulses. The pulsed-laser degradation was studied at different polymer concentrations and light intensities. Samples were analyzed by gel permeation chromatography. The degradation rate coefficients were determined by the application of a continuous distribution model. The photodegradation rates under UV exposure were highest at extremes of pH and were greatly enhanced by the addition of potassium chloride and potassium dichromate. The pulsed-laser degradation of the polymer decreased with increasing polymer concentration, although a threshold light intensity was required to initiate the degradation process.

The kinetics of the thermal and microwave-assisted oxidative degradation of poly(ethylene oxide) were determined with potassium persulfate as the oxidizing agent. Gel permeation chromatography was used to determine the variation of the molecular weight with time. The degradation was studied as a function of the temperature and persulfate concentration, and it was found that the degradation rate increased with the temperature and concentration of persulfate. Continuous distribution kinetics were used to determine the rate coefficients for the degradation process, and the activation energies were obtained. The results indicated that the microwave-assisted process had a lower activation energy of 10.3 kcal/mol, where as that of the thermal degradation was 25.2 kcal/mol.

Infrared chemiluminescence from a flow reactor has been used to study the H + CH2XI and N + CH2X(X = Cl, F, I, H) reactions at 300 K. Both the HI + CH2Cl and HCl + CH2I channels were identified for the H + CH2ClI reaction. The HCl channel involves adduct, HICH2Cl, formation as confirmed by the D + CH2ClI reaction, which gave both HCl and DCl products. The nascent HCl(upsilon) distribution from the H + CH2ClI reaction was P-1-P-5 = 25 : 29 : 26 : 13 : 7. The rate constant for the HCl(upsilon) formation channel is estimated to be 4 times smaller than that for the H + Cl-2 reaction. The highest HCl(upsilon) level observed from the H + CH2ClI reaction implies that the C-Cl bond energy is 50.2 kJ mol(-1) lower than that of the Cl-CH3 bond, which is in modest agreement with recent theoretical estimates. The H + CH2FI reaction gave a HF(upsilon) distribution of P-1-P-3 = 77 : 15 : 8. The C-F bond energy in CH2FI is estimated to be less than or equal to 460.2 kJ mol(-1), based on the highest HF(upsilon) level observed, the upper bound being the same as that of F-CH3. When N atoms are added to the flow reactor, the HCl(upsilon) emission intensities from H + CH2ClI increased by up to 2-fold, which is attributed to the N + CH2Cl --> HCl + HCN reaction. Concomitant weak emission from HCN and HNC could also be observed; however, the main product channel is thought to be NCH2 + Cl. Strong visible CN(A-X) emission was also observed when H/N/CH2XI were present in the reactor. If the CH2X radicals were produced by the F + CH3X reaction in the presence of N atoms, similar results were obtained. The N + CH2N reaction is proposed as the first step that leads to CN(A) formation with NCN as an intermediate.

The encapsulation of probiotic Lactobacillus acidophilus through layer-by-layer self-assembly of polyelectrolytes (PE) chitosan (CHI) and carboxymethyl cellulose (CMC) has been investigated to enhance its survival in adverse conditions encountered in the GI tract. The survival of encapsulated cells in simulated gastric (SGF) and intestinal fluids (SIF) is significant when compared to nonencapsulated cells. On sequential exposure to SGF and SIF for 120 min, almost complete death of free cells is observed. However, for cells coated with three nanolayers of PEs (CHI/CMC/CHI), about 33 log % of the cells (6 log cfu/500 mg) survived under the same conditions. The enhanced survival rate of encapsulated L. acidophilus can be attributed to the impermeability of polyelectrolyte nanolayers to large enzyme molecules like pepsin and pancreatin that cause proteolysis and to the stability of the polyelectrolyte nanolayers in gastric and intestinal pH. The PE coating also serves to reduce viability losses during freezing and freeze-drying. About 73 and 92 log % of uncoated and coated cells survived after freeze-drying, and the losses occurring between freezing and freeze-drying were found to be lower for the coated cells.

We have demonstrated the synthesis of light-sensitive polyelectrolyte capsules (PECs) by utilizing a novel polyol reduction method and investigated its applicability as photosensitive drug delivery vehicle. The nanostructured capsules were prepared via layer by layer (LbL) assembly of poly(allylamine hydrochloride) (PAN) and dextran sulfate (DS) on silica particles followed by in-situ synthesis of silver nanoparticles (NPs). Capsules without silver NPs were permeable to low molecular weight (A(w), 479 g/mol) rhodamine but impermeable to higher molecular weight fluorescence labeled dextran (FITC-dextran). However, capsules synthesized with silver NPs showed porous morphology and were permeable to higher molecular weight (M(w) 70 kDa) FITC-dextran also. These capsules were loaded with FITC-dextran using thermal encapsulation method by exploiting temperature induced shrinking of the capsules. During heat treatment the porous morphology of the capsules transformed into smooth pore free structure which prevents the movement of dextran into bulk during the loading process. When these loaded capsules are exposed to laser pulses, the capsule wall ruptured, resulting in the release of the loaded drug/dye. The rupture of the capsules was dependent on particle size, laser pulse energy and exposure time. The release was linear with time when pulse energy of 400 mu J was used and burst release was observed when pulse energy increased to 600 mu J.

The degradation of poly(ethylene oxide) and polyacrylamide in aqueous solution was studied with ascorbic acid. Gel permeation chromatograph was used to monitor molecular weight dynamics with time. A model based on continuous distribution kinetics showed that the experimental data matched well with theory. The results showed that the degradation of polymers is significantly enhanced in the presence of ascorbic acid. The degradation rate initially increased with ascorbic acid concentration but was independent of it at higher concentrations.

The effect of five different metal oxides on the pyrolysis of poly(ethylene oxide) (PEO), polyacrylamide (PAM), and poly(vinyl alcohol) (PVA) was investigated using thermogravimetry. The presence of metal oxide did not influence the degradation of PEO while the order of metal oxide on the degradation rate of PAM and PVA was PbO > $Co_3O_4$ > CuO > ZnO > $Al_2O_3$. The miscibility and the decomposition of PEO-PAM and PVA-PAM blends were also investigated. The blends were found to be immiscible and the presence of one polymer did not influence the degradation of the other polymer in the polymer blend.

The photocatalytic degradation of poly(ethylene oxide) (PEO) and polyacrylamide (PAM) was investigated using combustion synthesized nano-sized $TiO_2$ catalyst (CSN-$TiO_2$). The degradation was conducted with two different UV lamps of 125 and 80 W. Degradation of PEO was observed in both the cases, whereas PAM degraded only when exposed to lamp of higher power, even in the presence of catalyst. Gel permeation chromatography was used to determine the molecular weight distribution. Continuous distribution kinetics was applied to determine the kinetics of the photodegradation process. The degradation rate coefficients of the polymers in the presence of combustion synthesized $TiO_2$ were higher than the degradation rate coefficients obtained with commercially available $TiO_2$ (Degussa P-25). The enhanced degradation rate of the polymers when catalyzed by CSN-$TiO_2$ can be due to the nano-size, high surface area, and the presence of hydroxyl groups on the surface of the catalyst.

The kinetics of degradation of polyethylene oxide (PEO) and polyacrylamide (PAM) was investigated using a pulsed Nd:YAG laser, operating at 266 nm wavelength with $\sim 6$ ns pulses. Gel permeation chromatograph was used to monitor the change in molecular weight with time. Continuous distribution kinetics for random chain scission was used to obtain the rate coefficient for the degradation process. The measured rate coefficients for the degradation are $1.9\times 10^4$ and $1.2\times 10^4 \hspace {5mm} s^{-1}$ for PEO and PAM, respectively. A pathway for degradation has been proposed based on the experimental observations. The signi.cance of polymer concentration and the laser light intensity along with the requirement of oxygen for degradation has been correlated to the mechanism of the degradation process. The degradation was found to decrease with increasing polymer concentration while a threshold light intensity was required to initiate the degradation process.

The enzymatic degradation of poly(d,l-lactide) (PLA), poly(\epsilon-caprolactone) (PCL), and their blends by Novozym 435 was studied in toluene at 60 C. Both of the polymers were found to degrade by specific chain end scission. A model based on the continuous distribution kinetics was developed to determine the rate coefficient. The degradation rate coefficient was determined from the time evolution of the specific product. The pyrolytic degradation of these polymers and their blends was also investigated. The presence of PLA did not affect either the thermal or enzymatic degradation of PCL. It was thus concluded that the degradations of the polymers were independent of each other

The application of Bacillus subtilis as a flocculant for fine coal has been reported here. Zeta-potential measurements showed that both the coal and bacteria had similar surface charge as a function of pH. Surface free energy calculations showed that the coal was hydrophobic while the bacterium was hydrophilic. The adhesion of the bacteria to coal and subsequent settling was studied in detail. Adhesion of bacteria to coal surface and subsequent settling of coal was found to be quick. Both adhesion and settling were found to be independent of pH, which makes the process very attractive for field applications. The presence of an electrolyte along with the bacterium was found to not only enhance adhesion of bacteria, but also produce a clear supernatant. Further, the settled fraction was more compact than with bacteria alone. Interaction energy calculations using the extended DLVO theory showed that the electrical forces along with the acid-base interaction energy play a dominant role in the lower pH range. Above pH 7, the acid-base interaction energy is the predominant attractive force and is sufficient enough to overcome the repulsive forces due to electrical charges to brine about adhesion and thus settling of fine coal. With increase in electrolyte concentration, the change in total interaction energy with pH is minimal which probably leads to better adhesion and hence settling. (C) 2003 Elsevier Science B.V. All rights reserved.

Polystyrene cell-culture substrates were treated with argon glow discharge to make their surfaces hydrophilic. The process was novel in that it used a microwave electron cyclotron resonance (ECR) source for polymer surface modification. The substrates were processed at different microwave powers and time periods, and the surface modification was assessed with by measurement of the water contact angle. A decrease in contact angle was observed with increasing microwave power and processing time. Beyond a certain limit of power and duration of exposure, however, surface deterioration occurred. The optimum conditions for making the surfaces hydrophilic without deterioration of the samples were identified. The plasma parameters were assessed by Langmuir probe measurement. Fourier transform infrared spectroscopy with attenuated total reflectance showed evidence for the induction of hydrophilicity on the surface. The surface micromorphology was examined with scanning electron microscopy. The results prove that the ECR glow discharge was an efficient method for enhancing the wettability of the polymer surfaces.

The surface properties of coal and solution pH play a major role in determining the adhesion of microorganisms. In this study, three Indian coal samples with different compositions have been used and the adhesion of the bacterium Bacillus polymyxa to these coals has been investigated. It was found that due to the high ash content of coal, the zeta-potential was negative over most of the pH range which is close to the values exhibited by pure quartz as well as B. polymyxa. Similarly, the surface free energy components of coal (derived from contact angle measurements) showed that the electron-donor component increased with ash content. Adhesion experiments revealed that maximum adhesion of the bacterium B. polymyxa occurred on to the coal samples around the point-of-zero-charge of the coal and the bacterium i.e. about pH 2. Further, adhesion was found to be dependent on the ash content and the surface free energy of the coals. (C) 2002 Published by Elsevier Science Ltd.

Most Indian coals have high ash content of the order of 25-35%. High ash in the coal not only reduces the thermal value of coal but also leads to production of fly ash, which is a major environmental problem. Cleaning with gravity concentration techniques is ineffective and more efficient techniques need to be developed. In recent times, bioflocculation as an alternative preparation method has been reported for a number of mineral systems including high-sulfur coals. In this paper, bioflocculation of high-ash Indian coals has been studied using Paenibacillus polymyxa for two coal samples. A quartz sample was used for comparison purposes. Zeta-potential measurements showed that coal samples and the bacterium were negatively charged over most of the pH range with a point-of-zero-charge (PZC) around pH 2-3 Surface free energy, determined through contact angle measurements, showed that the coal samples were hydrophobic while the bacterium was hydrophilic. Among the coal samples, the coal with the lower ash content exhibited greater hydrophobicity. Adhesion tests revealed that adhesion took place in about 25 min and that maximum adhesion occurred around pH 2. Similarly, flocculation tests showed that the bacterium flocculated coal effectively and efficiently with the best results around pH 2. More than 90% of the coal flocculated in about a minute in the presence of the bacterium while compared to about 20-30% in the absence of the bacterium. Flocculation of quartz was retarded under the same conditions, indicating that it is dispersed. Ash analysis of the flocculated portion showed a decrease in ash by 60% thereby suggesting that selective flocculation of coal is possible.