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Abstract: In this communication exact analytical solution of the well known Saeman''s model equation, which is used to find the bed depth profile of the granular material flowing in a rotary kiln, has been obtained. Mathematically this model equation is characterized by a first order nonlinear ordinary differential equation and the exact analytical solution has been obtained in terms of an implicit form of elementary transcendental function by following the methods of separation of variables and partial fraction decomposition. To the best of the authors'' knowledge, this is perhaps the first attempt towards obtaining the exact analytical solution for the above model equation. The results obtained by using the exact analytical solution have been successfully verified against those obtained by using the numerical method and are found to be superior to those obtained by using the existing approximate analytical solutions. Besides, the exact analytical solution has also been fruitfully employed to simulate various experimental results available in literature. Furthermore, the effects of various parameters on the bed depth profile have also been briefly analyzed. [Copyright &y& Elsevier]

Studies of the lunar surface from Synthetic Aperture Radar (SAR) data have played a prominent role in the exploration of the lunar surface in recent times. This study uses data from SAR sensors from three Moon missions: Chandrayaan-1 Mini-SAR, Lunar Reconnaissance Orbiter (LRO) Mini-RF and Chandrayaan-2 Dual Frequency Synthetic Aperture Radar (DFSAR). DFSAR sensor is the first of its kind to operate at L-band and S-band in fully and hybrid polarimetric modes. Due to the availability of only L-band data out of the two bands (L-and S-band) for the study site, this study only used DFSAR's L-band data. The dielectric characterization and polarimetric analysis of the lunar north polar crater Hermite-A was performed in this study using Chandrayaan-1 Mini-SAR, LRO Mini-RF and Chandrayaan-2 DFSAR data. Hermite-A lies in the Permanently Shadowed Region (PSR) of the lunar north pole and whose PSR ID is NP_879520_3076780. Because of its location within the PSR of the lunar north pole, the Hermite-A makes an ideal candidate for a probable location of water-ice deposits. This work utilizes S-band hybrid polarimetric data of Mini-SAR and Mini-RF and L-band fully polarimetric data of DFSAR for the lunar north polar crater Hermite-A. This study characterizes the scattering mechanisms from three decomposition techniques of Hybrid Polarimetry namely m-delta, m-chi, and m-alpha decompositions, and for fully polarimetric data Barnes decomposition technique was applied which is based on wave dichotomy. Eigenvector and Eigenvalue-based decomposition model (H-A-Alpha decomposition) was also applied to characterize the scattering behavior of the crater. This study utilizes the hybrid-pol and fully polarimetric data-based Integral Equation Model (IEM) to retrieve the values of dielectric constant for Hermite-A crater. The dielectric constant values for the Hermite-A crater from Chandrayaan-1 Mini-SAR and LRO Mini-RF are similar, which goes further in establishing the presence of water-ice in the region. The values of the dielectric constant for Chandrayaan-2 in some regions of the crater especially on the left side of the crater is also around 3 but overall the range is relatively higher than the compact/hybrid polarimetric data. The dielectric characterization and polarimetric analysis of the Hermite-A indicatively illustrate that the crater may have surface ice clusters in its walls and on some areas of the crater floor, which can be explored in the future from the synergistic use of remote sensing data and in-situ experiments to confirm the presence of the surface ice clusters. [ABSTRACT FROM AUTHOR]

We evaluate the penetration depth of synthetic aperture radar (SAR) signals into the ground surface at different frequencies. We applied dielectric models (Dobson empirical, Hallikainen, and Dobson semi-empirical) on the ground surface composed of different soil types (sandy, loamy, and clayey). These models result in different penetration depths for the same set of sensors and soil properties. The Dobson semi-empirical model is more sensitive to the soil properties, followed by the Hallikainen and Dobson empirical models. We used the Dobson semi-empirical model to study the penetration depth of the upcoming NASA-ISRO synthetic aperture radar (NISAR) mission operated at the L-band (1.25 GHz) and the S-band (3.22 GHz) into the ground. We observed that depending upon the soil types, the penetration depth of the SAR signals ranges between 0 to 10 cm for the S-band and 0 to 25 cm for the L-band. [ABSTRACT FROM AUTHOR]

The effects of agitation and aeration rates on copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] production by Azohydromonas lata MTCC 2311 using cane molasses supplemented with propionic acid in a bioreactor were investigated. The experiments were conducted in a three-level factorial design by varying the impeller (150-500 rev min) and aeration (0.5-1.5 vvm) rates. Further, the data were fitted to mathematical models [quadratic polynomial equation and artificial neural network (ANN)] and process variables were optimized by genetic algorithm-coupled models. ANN and hybrid ANN-GA were found superior for modeling and optimization of process variables, respectively. The maximum copolymer concentration of 7.45 g l with 21.50 mol% of 3HV was predicted at process variables: agitation speed, 287 rev min; and aeration rate, 0.85 vvm, which upon validation gave 7.20 g l of P(3HB-co-3HV) with 21 mol% of 3HV with the prediction error (%) of 3.38 and 2.32, respectively. Agitation speed established a relative high importance of 72.19% than of aeration rate (27.80%) for copolymer accumulation. The volumetric gas-liquid mass transfer coefficient ( k a) was strongly affected by agitation and aeration rates. The highest P(3HB-co-3HV) productivity of 0.163 g l h was achieved at 0.17 s of k a value. During the early phase of copolymer production process, 3HB monomers were accumulated, which were shifted to 3HV units (9-21%) during the cultivation period of 24-42 h. The enhancement of 7.5 and 34% were reported for P(3HB-co-3HV) production and 3HV content, respectively, by hybrid ANN-GA paradigm, which revealed the significant utilization of cane molasses for improved copolymer production. [ABSTRACT FROM AUTHOR]

Abstract: The present work describes the optimization of medium variables for the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] by Azohydromonas lata MTCC 2311 using cane molasses supplemented with propionic acid. Genetic algorithm (GA) has been used for the optimization of P(3HB-co-3HV) production through the simulation of artificial neural network (ANN) and response surface methodology (RSM). The predictions by ANN are better than those of RSM and in good agreement with experimental findings. The highest P(3HB-co-3HV) concentration and 3HV content have been reported as 7.35g/l and 16.84mol%, respectively by hybrid ANN–GA. Upon validation, 7.20g/l and 16.30mol% of P(3HB-co-3HV) concentration and 3HV content have been found in the shake flask, whereas 6.70g/l and 16.35mol%, have been observed in a 3l bioreactor, respectively. The specific growth rate and P(3HB-co-3HV) accumulation rate of 0.29 per h and 0.16g/lh determined with cane molasses are comparable to those observed on pure substrates. [Copyright &y& Elsevier]

Abstract: Many problems of physical and engineering sciences are described by singular boundary value problems (SBVPs). Due to the presence of singularity, these problems pose difficulties in obtaining their solutions, and various solution schemes have been proposed to overcome these difficulties. The present work is concerned with the application of one such recently developed method, namely optimal homotopy analysis method (OHAM), to solve SBVPs. The OHAM has certain advantages: (i) it is a general method, (ii) contains an adjustable parameter to control the convergence of solution, and (iii) for certain choices of auxiliary quantities, its working resembles with those of other similar methods. The effectiveness of the OHAM has been evaluated by successfully solving two SBVPs given in recent literature as well a SBVP related to the reaction–diffusion process in a spherical catalyst. The obtained results for these problems show an excellent agreement when compared with the numerical/exact/available solutions. [Copyright &y& Elsevier]

Abstract: Metabolic engineering to enhance production of isoprenoid metabolites for industrial and medical purposes is an important goal. The substrate for isoprenoid synthesis in plants is produced by the mevalonate pathway (MEV) in the cytosol and by the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway in plastids. A multi-gene approach was employed to insert the entire cytosolic MEV pathway into the tobacco chloroplast genome. Molecular analysis confirmed the site-specific insertion of seven transgenes and homoplasmy. Functionality was demonstrated by unimpeded growth on fosmidomycin, which specifically inhibits the MEP pathway. Transplastomic plants containing the MEV pathway genes accumulated higher levels of mevalonate, carotenoids, squalene, sterols, and triacyglycerols than control plants. This is the first time an entire eukaryotic pathway with six enzymes has been transplastomically expressed in plants. Thus, we have developed an important tool to redirect metabolic fluxes in the isoprenoid biosynthesis pathway and a viable multigene strategy for engineering metabolism in plants. [Copyright &y& Elsevier]

Abstract: Biodegradation of resorcinol and p-cresol using fungus Gliomastix indicus MTCC 3869 was investigated in batch culture experiments at 28°C temperature and pH of 6 in the medium up to the initial concentration of 1300mg/L and 700mg/L for resorcinol and p-cresol, respectively. Five specific growth kinetic models and five specific degradation rate models were fitted to the experimental data in order to get best fitted kinetic models. The variation of observed growth yield and maintenance energy requirement with the initial substrate concentration was also studied. The model for maintenance energy coefficient was fitted to the experimental data. The model parameters were: m 1 =0.0135h−1, k =0.054, μ max =0.132h−1 for resorcinol and m 1 =0.0229h−1, k =0.011, μ max =0.102h−1 for p-cresol. Two mathematical models comprising of two sets of ODE were solved simultaneously to get degradation profiles with time. The model with varying growth yield and maintenance energy was found to be most appropriate biodegradation model. [Copyright &y& Elsevier]

In this study the application of a newly developed efficient method namely, optimal homotopy analysis method (OHAM) has been illustrated for solving nonlinear singular boundary value problems (SBVPs) which frequently arise in chemical and biochemical engineering. For demonstration, the reaction-diffusion process occurring in a spherical permeable biocatalyst has been successfully solved with the Michaelis-Menten form of kinetics. The obtained OHAM results match well with the numerical solutions and are found to be equally good or superior to those obtained by available approximate method. OHAM is a flexible method and can be applied to solve different types of singular or nonsingular BVPs. Moreover, it can easily be implemented in various symbolic soft computing tools, e.g. MATHEMATICA, MAPLE. [ABSTRACT FROM AUTHOR]

In this work, three nonlinear heat transfer problems namely, steady state heat conduction in a rod, unsteady cooling of a lumped system and steady state heat transfer from a rectangular fin into the free space by the radiation mechanism, have been solved analytically. Earlier these three problems were solved by various researchers by using homotopy perturbation, homotopy analysis and optimal homotopy analysis methods and the approximate series solutions were obtained. Here, we have obtained exact analytical solutions of these three problems in terms of a simple algebraic function, a Lambert W function and the Gauss's hypergeometric function, respectively. These exact solutions agree very well with those obtained by the numerical schemes and are better than the recent approximate solutions. Moreover, these can also serve as the yardsticks for future testing of the approximate solutions. [ABSTRACT FROM AUTHOR]

Abstract: This study uses econometric models to measure the effect of significant wave height and wind strength on the probability of casualty and tests whether these effects changed. While both effects are in particular relevant for stability and strength calculations of vessels, it is also helpful for the development of ship construction standards in general to counteract increased risk resulting from changing oceanographic conditions. The authors analyzed a unique dataset of 3.2 million observations from 20,729 individual vessels in the North Atlantic and Arctic regions gathered during the period 1979–2007. The results show that although there is a seasonal pattern in the probability of casualty especially during the winter months, the effect of wind strength and significant wave height do not follow the same seasonal pattern. Additionally, over time, significant wave height shows an increasing effect in January, March, May and October while wind strength shows a decreasing effect, especially in January, March and May. The models can be used to simulate relationships and help understand the relationships. This is of particular interest to naval architects and ship designers as well as multilateral agencies such as the International Maritime Organization (IMO) that establish global standards in ship design and construction. [Copyright &y& Elsevier]

Abstract: The modelling study on simultaneous adsorption of phenol and resorcinol onto granular activated carbon (GAC) in multicomponent solution was carried out at 303K by conducting batch experiments at initial concentration range of 100–1000mg/l. Three equilibrium isotherm models for multicomponent adsorption studies were considered. In order to determine the parameters of multicomponent adsorption isotherms, individual adsorption studies of phenol and resorcinol on GAC were also carried out. The experimental data of single and multicomponent adsorption were fitted to these models. The parameters of multicomponent models were estimated using error minimization technique on MATLAB R2007a. It has been observed that for low initial concentration of adsorbate (100–200mg/l), modified Langmuir model represents the data very well with the adsorption constant (Q 0), 216.1, 0.032 and average relative error (ARE) of 8.34, 8.31 for phenol and resorcinol respectively. Whereas, for high initial concentration of adsorbate (400–1000mg/l), extended Freundlich model represents the data very well with adsorption constant (K F) of 25.41, 24.25 and ARE of 7.0, 6.46 for phenol and resorcinol respectively. The effect of pH of solution, adsorbent dose and initial concentrations of phenol and resorcinol on adsorption behaviour was also investigated. [ABSTRACT FROM AUTHOR]

The communication infrastructure of a complex multicore system-on-a-chip is getting an increasing fraction of the overall chip area. According to the International Technology Roadmap for Semiconductors, killer defect density does not decrease over successive technology generations. For this reason, the probability that a manufacturing defect affects the communication system is predicted to increase. In this paper, we deal with manufacturing defects which affect the links in a network-on-chip-based interconnection system. The goal of this paper is to show that by using effective routing functions, supported by appropriate selection policies and with a limited amount of extra logic in the router, it is easy to exploit partially faulty links to improve the performance of the system. We show that, instead of discarding partially faulty links, they can be used at reduced capacity to improve the distribution of the traffic over the network, yielding performance and power improvements. We couple an application-specific routing function with a set of selection policies which are aware of link fault distribution and evaluate them on both synthetic traffic and a real complex multimedia application. We also present an implementation of the router, augmented with the extra logic, to support both the proposed selection functions and the transmission of messages over partially faulty links. We analyze the router in terms of silicon area, timing, and power dissipation. [ABSTRACT FROM AUTHOR]

Abstract: A one-dimensional non-isothermal model for oxygen permeable membrane reactor has been developed to simulate the partial oxidation of methane to produce hydrogen. The performance of two fixed bed reactors (FBRs) viz. one with pure O2 in feed (FBR1), other with air in feed (FBR2), and a membrane reactor (MR) having air in non-reaction side have been studied at various feed conditions and inlet temperatures in order to investigate the effect of these parameters on conversion of methane and yield of hydrogen. The fixed bed reactor with pure O2 in feed has been found to provide better performance as compared to fixed bed reactor with air and membrane reactor. [Copyright &y& Elsevier]

In democratic society, Police play an important role in prevention of crime and maintenance of law and order. Besides this police have another role in preservation of human rights and safeguarding the interest of weaker section of the society in order to justify the notion of welfare state in a democratic country like India. However, over the years, Indian Police while performing its administration of criminal justice process in the country have also earned some bad name due to showing its disrespect to human rights norms. Police atrocities and violation human rights become the common feature with image of Indian police. Insensitive behaviour of police towards human rights also causes the loosing of public trust on police. Therefore there is need to reform the Indian police administration to meet the new challenges and to orient the police behaviour and more human rights sensitivity. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear suboptimal three-dimensional guidance strategy based on a finite-time state-dependent Riccati equation technique is proposed to achieve interception of a non-maneuvering target at a desired impact time. To design the proposed guidance, range error for a spatial engagement between an interceptor and non-maneuvering target is introduced as the difference between the desired range-to-go and range-to-go of the predicted interception point. It is shown that forcing the range error and its rate to the origin are sufficient to achieve impact time constrained interception. Several existing impact time guidance strategies require a time-to-go estimate, to implement their guidance command, which may become erroneous in the presence of measurement noise and affect their performance. However, the proposed guidance does not require any such time-to-go estimate in its design process. Furthermore, guidance for the case of planar engagements is shown to be a special case of the proposed guidance scheme. Finally, numerical simulation studies for multiple engagement geometries, along with a comparison study with an existing strategy, are provided to demonstrate the efficacy of the proposed technique. [ABSTRACT FROM AUTHOR]

This paper proposes integrated guidance and control design to intercept a target, which may execute various motions, at a pre-specified time of interception. The problem is addressed considering nonlinear engagement kinematics and the interceptor is steered using the combined effects of canard as well as tail configurations (dual-controlled interceptors). Different formulations of time-to-go, without the restrictive assumption of interceptor's small heading angle, have been used in deriving the guidance commands, allowing the proposed strategy to remain effective over a wide range of impact time values. A weighted effort allocation scheme, in canard and tail deflections, has been proposed to generate the required lateral acceleration. The overall design uses sliding mode control owing to its simplicity of design, while a nonlinear finite-time disturbance observer is used to estimate the target's maneuver. Finally, simulations are presented for various target motions, and time-constrained interception with an impaired actuator is also shown, vindicating the efficacy of the proposed technique. [ABSTRACT FROM AUTHOR]

This paper deals with nonsingular guidance and control design for an interceptor, using a decoupled approach, steered by the combined effects of both canard and tail, to intercept a moving but non-maneuvering target at a time specified a priori. First, interceptor's desired lateral acceleration, consisting of nominal and corrective components, is derived using deviated pursuit guidance. While the nominal component is the pursuit guidance law, the corrective component drives the time-to-go error to zero within a finite-time in an optimal manner. Using a desired error dynamics and a meaningful performance index, the lateral acceleration demand is minimized during the transient phase. With exact knowledge of time-to-go and the consideration of nonlinear kinematic model, the proposed design circumvents the errors arising out of any approximations. Interceptor's canard and tail deflection commands are derived using predefined-time convergent sliding mode control, which allows the autopilot to precisely track the commanded lateral acceleration within a time specified during design. Finally, simulations are presented for various cases to demonstrate the efficacy of the proposed design. [ABSTRACT FROM AUTHOR]

Abstract: The activated carbon was prepared from carbonaceous agriculture waste Parthenium hysterophorous by chemical activation using concentrated H2SO4 at 130±5°C. The prepared activated carbon was characterized and was found as an effective adsorbent material. In order to test the efficacy of parthenium based activated carbon (PAC), batch experiments were performed to carryout the adsorption studies on PAC for the removal of highly toxic pollutant p-cresol from aqueous solution. The p-cresol adsorption studies were also carried out on commercial grade activated carbon (AC) to facilitate comparison between the adsorption capabilities of PAC and AC. For PAC and AC, the predictive capabilities of two types of kinetic models and six types of adsorption equilibrium isotherm models were examined. The effect of pH of solution, adsorbent dose and initial p-cresol concentration on adsorption behaviour was investigated, as well. The adsorption on PAC and on AC was found to follow pseudo-first order kinetics with rate constant 0.0016min−1 and 0.0050min−1, respectively. The highest adsorptive capacity of PAC and AC for p-cresol solution was attained at pH 6.0. Further, as an adsorbent PAC was found to be as good as AC for removal of p-cresol upto a concentration of 500mg/l in aqueous solution. Freundlich, Redlich–Peterson, and Fritz–Schlunder models were found to be appropriate isotherm models for PAC while Toth, Radke–Prausnitz and Fritz–Schlunder were suitable models for AC to remove p-cresol from aqueous solution. [Copyright &y& Elsevier]

Abstract: Biodegradation of p-cresol by a pure culture of new filamentous fungal strain Gliomastix indicus was studied. The fungus strain was acclimatized to the higher concentration of 700mg/l of p-cresol in modified czapeck medium over a period of two months. The lag period was 24h. The shake flask batch experiments were carried out at temperature of 28°C and pH of 6 over a wide range of initial p-cresol concentration (10–700mg/l) keeping initial biomass concentration constant at 18.72mg/l. Experimentally it was observed that p-cresol was inhibitory type substrate and the inhibition effect of p-cresol became predominant above a concentration of 50mg/l. The kinetics of cell growth and p-cresol degradation were investigated. Six kinetic models (Haldane, Andrews, Webb, Yano, Aiba, and Teissier) were fitted to the experimental growth kinetic data. Models by Haldane, Andrews, Webb and Yano (correlation coefficient R 2 >0.99) were found to be most suitable models. In addition, the variation of observed yield coefficient Y X with specific growth rate μ g was investigated. The maintenance energy coefficient and true growth yield coefficient, were found to be 0.0227h−1 and 1.0708(mg/mg), respectively. The specific substrate utilization rate was represented in terms of specific biomass growth rate. The decay coefficient was found to be 0.0055h−1. The effect of pH and nitrogen source of medium on biodegradation of p-cresol was investigated as well. [Copyright &y& Elsevier]

Abstract: The mathematical modeling of fire growth and smoke movement in any enclosure is a formidable task. Two types of deterministic models are in vogue, zone models and field models (popularly known as CFD technique). CFAST is a popular zone model used for modeling of fires in enclosures. Likewise, CFX is a general purpose CFD code used for various purposes including modeling of fires. In the present paper, a tunnel of length 150m having a rectangular cross-section of 80m2 has been considered for analyzing the temperature and velocity profiles generated by fire, placed at a distance of 20m from one end of portal, by both CFAST and CFX. The simulation by CFAST has been carried out by dividing the tunnel into 1, 2, 5, 8, 10, 12 and 15 compartments of equal size, where these compartments are joined by openings or vents having same cross-section as that of the tunnel. In case of tunnel divided into 15 compartments the fire source position lies at the position of vent; CFAST predicted very high temperatures. The simulations have also been carried out by dividing tunnel into unequal sized compartments such that position of fire was at the center of the compartment. It was found that for accuracy of results, location of fire source inside compartment is an important factor. Computational difficulty was experienced when tunnel was divided into more than 15 compartments. In this paper, a comparative study of temperatures predicted by CFAST and CFX has been done. The CFX and CFAST predictions show that smoke temperature changes with a pattern roughly similar to that of heat release rate. The temperature profiles at selected positions cannot be predicted by CFAST unlike CFX. The detailed features like flame tilt, flow field can only be observed from CFX predictions. [Copyright &y& Elsevier]

Batch studies were carried out for studying the adsorption behaviour of phenol and 4-nitrophenol on granular activated carbon from a basal salt medium (BSM) at pH ≈7.1 and temperature ≈30°C. The literature review was done in order to review the information for comparison purposes on equilibrium models of phenol and 4-nitrophenol adsorption on activated carbon. The units for measurements reported in these models were found to be diverse, thus making the comparison difficult. These units have been converted into similar units for easy reference. In all, six models of Freundlich, Langmuir, Redlich–Peterson, Radke–Prausnitz, Toth and Fritz–Schlunder as reported in the literature have been fitted to the data of phenol/activated carbon and 4-nitrophenol/activated carbon systems of the present studies using nonlinear regression technique. Based on maximum deviations and correlation coefficients, Langmuir gave the poorest fit for both compounds; Redlich–Peterson, Radke–Prausnitz, and four parameter model of Fritz–Schlunder could represent the data with similar accuracy, i.e. with R 2-value of 0.98 and maximum deviation ≈12%. However, for phenol, two parameter model of Freundlich may be recommended because of ease in its parameter estimation and better accuracy. 4-Nitrophenol was found to be more adsorbed than phenol, which is consistent with the result found in literature. The kinetics of the adsorption was found to be intra-particle diffusion controlled with diffusion coefficient values of the order of 10−13 m2/s. Three distinct phases of kinetics – rapid, medium, and slow – have been observed in this study. [Copyright &y& Elsevier]

Abstract: Modelling of bioreactors employed in solid-state fermentation processes can play a crucial role in the analysis, design and development of bioprocesses based on the phenomena; which encompass a variety of applications ranging from the production of enzymes to the treatment of agro-industrial residues. In the present work, a mathematical model has been developed for a packed bed solid-state fermentation Bioreactor employing the N-tanks in series approach. The model analyses the production of protease enzyme by Aspergillus niger and is validated against an experimental study available in the literature which describes its growth during solid-state fermentation. The primary importance of employing the method is to demonstrate its successful application to the solution of model equations to situations where axial gradients dominate. As a consequence, the approach not only helps in avoiding the use of complex computational methods like orthogonal collocation but also contributes in providing insights to the design of bioreactors. [Copyright &y& Elsevier]

Chloroplast genetic engineering offers several unique advantages, including high-level transgene expression, multi-gene engineering in a single transformation event and transgene containment by maternal inheritance, as well as a lack of gene silencing, position and pleiotropic effects and undesirable foreign DNA. More than 40 transgenes have been stably integrated and expressed using the tobacco chloroplast genome to confer desired agronomic traits or express high levels of vaccine antigens and biopharmaceuticals. Despite such significant progress, this technology has not been extended to major crops. However, highly efficient soybean, carrot and cotton plastid transformation has recently been accomplished through somatic embryogenesis using species-specific chloroplast vectors. This review focuses on recent exciting developments in this field and offers directions for further research and development. [Copyright &y& Elsevier]

Abstract: Biological degradation of phenol and catechol by a bacterial strain of Pseudomonas putida (MTCC 1194) in basal salt medium (BSM) was investigated in shake-flask experiments at 29.9±0.3°C and pH of approximately 7.1. The lyophilized cultures of P. putida (MTCC 1194) were revived and exposed to increasing concentrations of phenol, and catechol in shake-flasks. This bacterial strain could be acclimatized to the concentrations of 1000 and 500mg/l for phenol and catechol, respectively, over a period of three months. The higher the concentration of phenol or catechol, the longer was the lag period. The well-acclimatized culture of P. putida (MTCC 1194) degraded the initial phenol concentration of 1000mg/l and initial catechol concentration of 500mg/l completely in 162 and 94h, respectively. Both the phenol and catechol were observed to be the inhibitory compounds. Monod''s and linearized-Haldane''s model could not represent the growth kinetics over the studied concentration range. However, Haldane''s growth kinetics model could be fitted to the growth kinetics data well for the entire concentration range. Further, the decay coefficients have been found to be 0.0056 and 0.0067h-1 for the growth on phenol and catechol, respectively. Besides, the yield coefficient for the growth on phenol and catechol were found to be 0.65 and 0.50mg/mg, respectively. It is our view that the above information would be useful for modeling and designing the units treating phenol- and catechol-containing wastewaters. [Copyright &y& Elsevier]

Investigations were conducted in the batch mode for studying the adsorption behavior of resorcinol and catechol on granular activated carbon from a basic salt medium (BSM) at pH≈7.1 and temperature≈30 °C. The isotherm data were correlated with six isotherm models, namely Langmuir, Freundlich, Redlich–Peterson, Radke–Prausnitz, Toth, and Fritz–Schlunder’s using a nonlinear regression technique. It is observed that the catechol isotherm data may be represented by Redlich–Peterson, Radke–Prausnitz, Toth, and Fritz–Schlunder models with similar accuracy (max. dev. 12%). And the resorcinol data may be represented by Freundlich, Redlich–Peterson, Radke–Prausnitz, and Fritz–Schlunder models equally well (max. dev. 15%). Freudlich being a simple model is recommended for resorcinol. At the conditions investigated in this study, catechol is adsorbed to a greater extent than resorcinol. This is due to the compound’s solubility and position of the –OH group on the benzene aromatic ring. The kinetics of adsorption have been found to be diffusion controlled and the value of effective particle diffusion coefficients is of the order of 10−13 m2/s. Three distinct phases of kinetics—rapid, medium, and slow—have been observed. These results should be useful for the design of adsorbers for removing these pollutants. [Copyright &y& Elsevier]

This paper addresses the problem of maximizing the warhead effectiveness, by achieving impact at the structurally vulnerable points of the targets. The impact direction is first defined using target frame, and then a unique relation between the desired impact angles and the desired line-of-sight angles is derived. Using this relation, two nonlinear guidance strategies, based on finite-time sliding mode and optimal control methods, are proposed to achieve interception of maneuvering targets at a pre-specified desired impact orientation. Unlike most of the existing three-dimensional guidance strategies, the proposed guidance strategies are derived without decoupling nonlinear coupled engagement kinematics into two mutually orthogonal planes and performing linearization, thereby avoiding possible performance deterioration for engagement with large heading errors. The performances of proposed guidance strategies are evaluated for various engagement geometries as well as constant speed and different realistic time-varying speed pursuer models subjected to aerodynamics parameter variations, and found to be satisfactory. [ABSTRACT FROM AUTHOR]

This paper presents a novel nonlinear guidance law for an autonomous unmanned aerial vehicle (UAV) that enables it to track any predefined path while taking into account wind effects. The approach involves treating the desired path as the trajectory of the virtual target, which the UAV tracks without relying on knowledge of the path's curvature. This makes the design applicable to paths with varying levels of complexity and smooth curvatures. Additionally, the proposed method draws inspiration from pursuit guidance, known for its simplicity and ease of implementation. Theoretical analysis ensures that the UAV will converge to the intended path within a fixed time, irrespective of its initial configuration relative to the path. Simulations demonstrate the effectiveness of the proposed method, showcasing the UAV's ability to accurately follow diverse curvilinear paths. [ABSTRACT FROM AUTHOR]

Apolipoprotein E (ApoE) has been associated with several diseases including Parkinson's disease, Alzheimer's and multiple sclerosis. ApoE also has documented immunomodulatory functions. We investigated gene expression in circulating monocytes and in bone marrows of patients with visceral leishmaniasis (VL) living in an endemic area in Bihar, India, and contrasted these with control healthy subjects or other diagnostic bone marrows from individuals in the same region. Samples from VL patients were obtained prior to initiating treatment. Our study revealed significant upregulated expression of the apoE transcript in patients with VL. Furthermore, the levels of ApoE protein were elevated in serum samples of subjects with VL compared with healthy endemic controls. These observations may provide clues regarding the complex interactions between lipid metabolism and immunoregulation of infectious and inflammatory diseases. [ABSTRACT FROM AUTHOR]

Upper gastrointestinal hemorrhage is one of the more important complications of cirrhosis. Most of the available data regarding the prevalence of upper and lower gastrointestinal sites of bleeding in cirrhotic patients have been obtained in individuals with alcoholic cirrhosis evaluated in the course of an acute gastrointestinal bleeding episode. Few data exist, however, as to the prevalence of either potential bleeding sites or of normal endoscopic findings in hemo-dynamically stable individuals with cirrhosis of any etiology. Five hundred ten cirrhotic subjects, who were evaluated for possible liver transplantation (OLTx) between January 1985 and June 1987, were included in this study. Seventy-five had alcoholic cirrhosis and 435 had nonalcoholic cirrhosis of various etiologies. Of these 510 patients, 412 underwent combined upper and lower gastrointestinal endoscopy and 98 underwent upper gastrointestinal endoscopy alone. Gastritis, gastric and duodenal ulcer disease were found significantly (each at least p < 0.025) more often in patients with alcoholic liver disease than in those with nonalcoholic liver disease. The prevalence of the various lower gastrointestinal lesions in both groups was similar. Of particular interest is the fact that in alcoholic cirrhotics, the prevalence of gastritis, gastric ulcer and duodenal ulcer disease was unrelated to the degree of portal hypertension, whereas in the nonalcoholic cirrhotics the prevalence of gastritis and duodenal ulcer disease but not gastric ulcer disease was associated significantly with the degree of portal hypertension as assessed by the presence or absence of large esophageal varices, ascites, and hepatic encephalopathy. [ABSTRACT FROM AUTHOR]

Simple Summary: The natural astaxanthin from algae (marketed only 5%) is the most powerful antioxidant for health compared to the synthetic that shares about 95% of the market. Therefore, there is a huge demand for natural astaxanthin from algae, which can accumulate significantly higher astaxanthin. We have isolated a new algal strain from the Himalayan region, Northern India, which was identified as Dysmorphococcus globosus-HI based on morphological and molecular analysis. Its growth conditions were optimized in the laboratory. Among the seven different tested culture media, MBBM and 3N-BBM provided the maximum growth and astaxanthin production. The highest biomass production (1.14 g L−1) was observed in the modified BBM medium. It is an excellent source of producing natural astaxanthin, to a tune of 391 mg L−1, which is greater than any other known algal species. The productivity of astaxanthin was about 15.6 mg L−1 d−1 under normal conditions, which is higher than the commercially used H. pluvialis species. It is the first report of natural astaxanthin production from D. globosus-HI that has great potential for commercial application. Synthesized astaxanthin (ASX), stereoisomers of 3S,3′R, 3R,3′R, and 3S,3′S, have over 95% market share and have relatively poor antioxidant and bioactivity properties, with persistent issues in terms of biological functions, health benefits, and biosafety if compared to natural ASX. Bioprospecting of new microalgal strains could be vital for a new source of powerful antioxidant (ASX). In this study, a new algal strain was isolated from the Indian foothills of the Himalayas. Its identity was discerned by morphological and DNA barcode studies. It is a unicellular spheroidal cell-shaped alga with 100–200 μm diameter. The isolate has 93.4% similarity to Dysmorphococcus globosus species based on 18S-rDNA phylogenetic analysis and named as D. globosus-HI (HI stands for Himalayan India). Its growth and major cellular components (carotenoids, carbohydrates, protein, lipids, fatty acid profile, and ASX) were optimized using the seven different culture media. The highest biomass (1.14 g L−1) was observed in the MBBM medium, with a specific growth rate (0.087 day−1), division/day (0.125), and cellular yield (6.16 x 106 cells/mL). The highest carotenoids (1.56 mg g−1), lipids (32.5 mg L−1), and carbohydrates (135.62 mg L−1) were recorded in the 3N-BBM medium. The maximum ω3-FAs (17.78%), ω6-FAs (23.11%), and ω9-FAs (7.06%) were observed in MBBM, JW, and BG-11 medium respectively. The highest amount of antioxidant ASX was accumulated in the 3N-BBM medium (391 mg L−1). It is more than any other known algal species used in the production of natural ASX. The optimized biochemical studies on the D. globosus-HI strain should fulfill the increasing demand for natural ASX for commercial application. [ABSTRACT FROM AUTHOR]

Spaceborne and airborne polarimetric synthetic-aperture radar interferometry (PolInSAR) data have been extensively used for forest parameter retrieval. The PolInSAR models have proven their potential in the accurate measurement of forest vegetation height. Spaceborne monostatic multifrequency data of different SAR missions and the Global Ecosystem Dynamics Investigation (GEDI)-derived forest canopy height map were used in this study for vegetation height retrieval. This study tested the performance of PolInSAR complex coherence-based inversion models for estimating the vegetation height of the forest ranges of Doon Valley, Uttarakhand, India. The inversion-based forest height obtained from the three-stage inversion (TSI) model had higher accuracy than the coherence amplitude inversion (CAI) model-based estimates. The vegetation height values of GEDI-derived canopy height map did not show good relation with field-measured forest height values. It was found that, at several locations, GEDI-derived forest height values underestimated the vegetation height. The statistical analysis of the GEDI-derived estimates with field-measured height showed a high root mean square error (RMSE; 5.82 m) and standard error (SE; 5.33 m) with a very low coefficient of determination (R2; 0.0022). An analysis of the spaceborne-mission-based forest height values suggested that the L-band SAR has great potential in forest height retrieval. TSI-model-based forest height values showed lower p-values, which indicates the significant relation between modelled and field-measured forest height values. A comparison of the results obtained from different SAR systems is discussed, and it is observed that the L-band-based PolInSAR inversion gives the most reliable result with low RMSE (2.87 m) and relatively higher R2 (0.53) for the linear regression analysis between the modelled tree height and the field data. These results indicate that higher wavelength PolInSAR datasets are more suitable for tree canopy height estimation using the PolInSAR inversion technique. [ABSTRACT FROM AUTHOR]

A case of a slow growing painless swelling of the dorsum of the hand in reported. The swelling was excised along with the corresponding rendon slip. A cortical window was made in the underlying metacarpal and the medullary cavity examined to rule out medullary extension. The histopathology report confirmed the diagnosis as Desmoplastic Fibroma. Desmoplastic fibroma is a rare benign tumor of myofibroblastic origin. It is important to differentiate desmoplastic fibroma from low-grade fibromyxoid sarcoma and Desmoid tumours, because they require a more aggressive surgical approach and in the case of sarcomas, might require adjuvant therapies. [ABSTRACT FROM AUTHOR]

Polarimetric synthetic aperture radar (PolSAR) remote sensing has been widely used for forest mapping and monitoring. PolSAR data has the capability to provide scattering information that is contributed by different scatterers within a single SAR resolution cell. A methodology for a PolSAR-based extended water cloud model (EWCM) has been proposed and evaluated in this study. Fully polarimetric phased array type L-band synthetic aperture radar (PALSAR) data of advanced land observing satellite (ALOS) was used in this study for forest aboveground biomass (AGB) retrieval of Dudhwa National Park, India. The shift in the polarization orientation angle (POA) is a major problem that affects the PolSAR-based scattering information. The two sources of POA shift are Faraday rotation angle (FRA) and structural properties of the scatterer. Analysis was carried out to explore the effect of FRA in the SAR data. Deorientation of PolSAR data was implemented to minimize any ambiguity in the scattering retrieval of model-based decomposition. After POA compensation of the coherency matrix, a decrease in the power of volume scattering elements was observed for the forest patches. This study proposed a framework to extend the water cloud model for AGB retrieval. The proposed PolSAR-based EWCM showed less dependency on field data for model parameters retrieval. The PolSAR-based scattering was used as input model parameters to derive AGB for the forest area. Regression between PolSAR-decomposition-based volume scattering and AGB was performed. Without deorientation of the PolSAR coherency matrix, EWCM showed a modeled AGB of 92.90 t ha−1, and a 0.36 R2 was recorded through linear regression between the field-measured AGB and the modeled output. After deorientation of the PolSAR data, an increased R2 (0.78) with lower RMSE (59.77 t ha−1) was obtained from EWCM. The study proves the potential of a PolSAR-based semiempirical model for forest AGB retrieval. This study strongly recommends the POA compensation of the coherency matrix for PolSAR-scattering-based semiempirical modeling for forest AGB retrieval. [ABSTRACT FROM AUTHOR]

This paper proposes a polynomial-based three-dimensional (3D) impact angle-constrained guidance law considering the seeker's field-of-view (FOV) bound. The guidance laws are derived using nonlinear coupled dynamics of the interceptor-target engagement against stationary as well as constant velocity targets. Line-of-sight (LOS) orientations between the interceptor and the target in both pitch and yaw planes are shaped as two cubic polynomial functions of relative range. An explicit expression for the look angle of the interceptor is acquired in terms of the LOS polynomials. This expression facilitates the embodiment of the FOV constraint in the boundary conditions inflicted on the polynomials. A system of equations with the eight unknown coefficients is obtained by employing the appropriate launch and terminal conditions of the interceptor-target engagement. Reference LOS angle and lead angle profiles are generated using the calculated coefficients, complying to which the interceptor achieves a zero miss distance with desired impact angle and FOV constraints. A tracking controller is then designed using a nonlinear control technique that enables the interceptor to follow reference lead angle profiles in mutually orthogonal planes. Unlike the already existing guidance strategies for 3D impact angle and FOV-constrained target interception, the proposed nonlinear guidance strategy is designed without the use of linearization or decoupling. Moreover, no switching logic or multi-phase guidance structures are employed in the proposed guidance strategy, which eliminates possible jumps in the guidance command. The effectiveness of the proposed guidance law is validated using numerical simulations, along with a comparison study with the existing strategy. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "A conceptual study on novel current mirror integrated cantilever (CMIC) mass sensor for micro-gram (µg) range sensing applications" published in the journal Microsystems Technologies. The correction addresses an error in the affiliation of two authors, providing the correct affiliations for Kalpana Gogoi and Shashi Kumar. The original article has been corrected. The publisher, Springer Nature, remains neutral regarding jurisdictional claims and institutional affiliations. [Extracted from the article]

The paper aims to investigate the steam reforming of biogas in an industrial-scale reformer for hydrogen production. A non-isothermal one dimensional reactor model has been constituted by using mass, momentum and energy balances. The model equations have been solved using MATLAB software. The developed model has been validated with the available modeling studies on industrial steam reforming of methane as well as with the those on lab-scale steam reforming of biogas. It demonstrates excellent agreement with them. Effect of change in biogas compositions on the performance of industrial steam reformer has been investigated in terms of methane conversion, yields of hydrogen and carbon monoxide, product gas compositions, reactor temperature and total pressure. For this, compositions of biogas (CH 4 /CO 2 = 40/60 to 80/20), S/C ratio, reformer feed temperature and heat flux have been varied. Preferable feed conditions to the reformer are total molar feed rate of 21 kmol/h, steam to methane ratio of 4.0, temperature of 973 K and pressure of 25 bar. Under these conditions, industrial reformer fed with biogas, provides methane conversion (93.08–85.65%) and hydrogen yield (1.02–2.28), that are close to thermodynamic equilibrium condition. • A model for an industrial reformer for steam reforming of biogas (SRB) developed. • Preferable process feed conditions are P = 25 bar, T = 973 K, S/C = 4 and heat flux = 65 kW/m2. • An existing industrial reformer for steam reforming of methane can be used for SRB. • Performance of industrial reformer is close to that achieved at equilibrium. • The study provides the guidelines for industrial steam reforming of biogas (SRB). [ABSTRACT FROM AUTHOR]