Force induced melting of the constrained DNA

We develop a simple model to study the effects of an applied force on the melting of a double stranded DNA (dsDNA). Using this model, we could study the stretching, unzipping, rupture and slippage like transition in a dsDNA. We show that in absence of an applied force, the melting temperature and the melting profile of dsDNA strongly depend on the constrained imposed on the ends of dsDNA. The nature of the phase boundary which separates the zipped and the open state for the shearing like transition is remarkably different than the DNA unzippingComment: 8 pages, 10 figure

Automatic generation control of a hydro - thermal and thermal - thermal systems in a deregulated environment

This paper deals with the applications of automatic generation control (AGC) of a hydro —thermal and thermal—thermal systems in a power system deregulated environment and makes an attempt to provide a new practical AGC model to fulfill the needs of a modern restructured hydro-thermal and thermal -thermal power system. Several Distribution Company, distribution Participation Matrix,and area participation factor have been tried out and dynamic responses for frequency, tie line flow and power generations are obtained to examine the performance of the system in deregulated environment considering integral controllers. Investigations have been also carried out to study the effect of generation rate constraint and the importance of APF in deregulated environment. Study also reveals that the conventional integral controllers are quite robust than PI and PID controllers and the optimum integral gains once set for nominal condition need not be changed for +25% variations in system parameters and +20% variations in operating load condition from their nominal values

Effects of Molecular Crowding on stretching of polymers in poor solvent

We consider a linear polymer chain in a disordered environment modeled by percolation clusters on a square lattice. The disordered environment is meant to roughly represent molecular crowding as seen in cells. The model may be viewed as the simplest representation of biopolymers in a cell. We show the existence of intermediate states during stretching arising as a consequence of molecular crowding. In the constant distance ensemble the force-extension curves exhibit oscillations. We observe the emergence of two or more peaks in the probability distribution curves signaling the coexistence of different states and indicating that the transition is discontinuous unlike what is observed in the absence of molecular crowding.Comment: 14 pages, 6 figure

The statistical laws of popularity: Universal properties of the box office dynamics of motion pictures

Are there general principles governing the process by which certain products or ideas become popular relative to other (often qualitatively similar) competitors? To investigate this question in detail, we have focused on the popularity of movies as measured by their box-office income. We observe that the log-normal distribution describes well the tail (corresponding to the most successful movies) of the empirical distributions for the total income, the income on the opening week, as well as, the weekly income per theater. This observation suggests that popularity may be the outcome of a linear multiplicative stochastic process. In addition, the distributions of the total income and the opening income show a bimodal form, with the majority of movies either performing very well or very poorly in theaters. We also observe that the gross income per theater for a movie at any point during its lifetime is, on average, inversely proportional to the period that has elapsed after its release. We argue that (i) the log-normal nature of the tail, (ii) the bimodal form of the overall gross income distribution, and (iii) the decay of gross income per theater with time as a power law, constitute the fundamental set of {\em stylized facts} (i.e., empirical "laws") that can be used to explain other observations about movie popularity. We show that, in conjunction with an assumption of a fixed lower cut-off for income per theater below which a movie is withdrawn from a cinema, these laws can be used to derive a Weibull distribution for the survival probability of movies which agrees with empirical data. The connection to extreme-value distributions suggests that popularity can be viewed as a process where a product becomes popular by avoiding failure (i.e., being pulled out from circulation) for many successive time periods. We suggest that these results may apply to popularity in general.Comment: 14 pages, 11 figure

Theoretical Bounds on Control-Plane Self-Monitoring in Routing Protocols

Routing protocols rely on the cooperation of nodes in the network to both forward packets and to select the forwarding routes. There have been several instances in which an entire network's routing collapsed simply because a seemingly insignificant set of nodes reported erroneous routing information to their neighbors. It may have been possible for other nodes to trigger an automated response and prevent the problem by analyzing received routing information for inconsistencies that revealed the errors. Our theoretical study seeks to understand when nodes can detect the existence of errors in the implementation of route selection elsewhere in the network through monitoring their own routing states for inconsistencies. We start by constructing a methodology, called Strong-Detection, that helps answer the question. We then apply Strong-Detection to three classes of routing protocols: distance-vector, path-vector, and link-state. For each class, we derive low-complexity, self-monitoring algorithms that use the routing state created by these routing protocols to identify any detectable anomalies. These algorithms are then used to compare and contrast the self-monitoring power these various classes of protocols possess. We also study the trade-off between their state-information complexity and ability to identify routing anomalies

Changes in biochemical constituents and defense related enzymes in response to red spider mite incidence in tea

In recent years, red spider mite (RSM), Oligonychus coffeae (Nietner) menace challenged the crop productivity in tea. Though the reports on bush physiology are available, a compressive data on changes in biochemical constituents including enzymes is lacking. Crop shoots were collected from the field grown tea plants (UPASI-3 & UPASI-10) and segregated into healthy, moderately infested (~4 mites leaf–1) and severely infested (>4 mites leaf–1). The crop shoots were used for determining the biochemical constituents and quality. Stress-related enzymes such as catalase, superoxide dismutase, glutathione reductase and ascorbate peroxidase were also analysed. Irrespective of the RSM damage, UPASI-3 significantly recorded higher amount of polyphenols, catechins, amino acids, reducing sugars and carotenoids. UPASI-10 possessed higher amount of total chlorophylls than that of UPASI-3. Irrespective of the clones, polyphenols, catechins, and pigments linearly decreased with severity of RSM infestation while reducing sugars and hydrogen peroxide linearly increased. Irrespective of the RSM damage, crop shoots of UPASI-10 contained significantly lower amount of quality parameters and stress-related enzymes, except polyphenol oxidase. Though quality related enzymes enhanced due to RSM attack initially and declined when the RSM infestation was severe. All the stress related enzymes progressively increased with the increasing degree of RSM damage. Interactions between activities of enzymes and clones with respect to RSM damage were elucidated

Quality related substrates and enzyme in tea as influenced by weather parameters

Recent threat on global warming and change in climate are not only the topic related with agricultural and biomass productivity; but on the basis of quality consciousness consumers demand, agriculturalists are indebted to offer due importance to the quality of the agricultural commodities. Quality attributes depends mainly upon the biochemical constituents. How far climatic changes influence the quality attributes of tea are unknown. In the pilot scale study, polyphenols, catechins and their oxidative enzyme are considered and variations in their ratios with respect to prevailing climatic conditions of the Anamallais are attempted. Crop shoots were collected at monthly intervals and subjected to determination of polyphenols, catechins and polyphenol oxidase assay. Weather data collected at UPASI meteorological observatory were used for correlation and factor analysis. Irrespective of the clones, "Cambod" cultivars registered higher quantum of polyphenols followed by "Assam" cultivar. Clones studied within the taxonomic group also significantly varied among them, irrespective of the sampling time. As the catechins are polyphenol derivates, the same trend was observed with total catechin content. Among the clones, SA-6 registered least amount of polyphenols and catechins when compared to other clones. Ratio of catechin to polyphenol exhibited different trend; "Cambod" cultivars registered higher values in catechin, polyphenol ratio followed by "China" and "Assam" cultivars. Polyphenol oxidase activity was significantly varied among the jats and the clones within the taxa. Microclimatic variables played an important role in accumulation of predominant quality constituents, polyphenols or catechins and the enzyme, poly phenol oxidase. Sunshine hours positively related with the above said biochemicals while rainfall has negative influence on the biochemical constituents. Maximum temperature had positive and significant correlation with quality constituents whereas, minimum temperature registered negative impact on their production. Relative humidity recorded at 8.00 am and 2.30 pm exerted negative influence on polyphenols, catechins and PPO activity. Multiple regression models derived based on the climatic variables are presented and discussed in detail

Quality related substrates and enzyme in tea as influenced by weather parameters

Recent threat on global warming and change in climate are not only the topic related with agricultural and biomass productivity; but on the basis of quality consciousness consumers demand, agriculturalists are indebted to offer due importance to the quality of the agricultural commodities. Quality attributes depends mainly upon the biochemical constituents. How far climatic changes influence the quality attributes of tea are unknown. In the pilot scale study, polyphenols, catechins and their oxidative enzyme are considered and variations in their ratios with respect to prevailing climatic conditions of the Anamallais are attempted. Crop shoots were collected at monthly intervals and subjected to determination of polyphenols, catechins and polyphenol oxidase assay. Weather data collected at UPASI meteorological observatory were used for correlation and factor analysis. Irrespective of the clones, "Cambod" cultivars registered higher quantum of polyphenols followed by "Assam" cultivar. Clones studied within the taxonomic group also significantly varied among them, irrespective of the sampling time. As the catechins are polyphenol derivates, the same trend was observed with total catechin content. Among the clones, SA-6 registered least amount of polyphenols and catechins when compared to other clones. Ratio of catechin to polyphenol exhibited different trend; "Cambod" cultivars registered higher values in catechin, polyphenol ratio followed by "China" and "Assam" cultivars. Polyphenol oxidase activity was significantly varied among the jats and the clones within the taxa. Microclimatic variables played an important role in accumulation of predominant quality constituents, polyphenols or catechins and the enzyme, poly phenol oxidase. Sunshine hours positively related with the above said biochemicals while rainfall has negative influence on the biochemical constituents. Maximum temperature had positive and significant correlation with quality constituents whereas, minimum temperature registered negative impact on their production. Relative humidity recorded at 8.00 am and 2.30 pm exerted negative influence on polyphenols, catechins and PPO activity. Multiple regression models derived based on the climatic variables are presented and discussed in detail

Changes in biochemical constituents and defense related enzymes in response to red spider mite incidence in tea

In recent years, red spider mite (RSM), Oligonychus coffeae (Nietner) menace challenged the crop productivity in tea. Though the reports on bush physiology are available, a compressive data on changes in biochemical constituents including enzymes is lacking. Crop shoots were collected from the field grown tea plants (UPASI-3 & UPASI-10) and segregated into healthy, moderately infested (~4 mites leaf–1) and severely infested (>4 mites leaf–1). The crop shoots were used for determining the biochemical constituents and quality. Stress-related enzymes such as catalase, superoxide dismutase, glutathione reductase and ascorbate peroxidase were also analysed. Irrespective of the RSM damage, UPASI-3 significantly recorded higher amount of polyphenols, catechins, amino acids, reducing sugars and carotenoids. UPASI-10 possessed higher amount of total chlorophylls than that of UPASI-3. Irrespective of the clones, polyphenols, catechins, and pigments linearly decreased with severity of RSM infestation while reducing sugars and hydrogen peroxide linearly increased. Irrespective of the RSM damage, crop shoots of UPASI-10 contained significantly lower amount of quality parameters and stress-related enzymes, except polyphenol oxidase. Though quality related enzymes enhanced due to RSM attack initially and declined when the RSM infestation was severe. All the stress related enzymes progressively increased with the increasing degree of RSM damage. Interactions between activities of enzymes and clones with respect to RSM damage were elucidated

A Heuristic Based Multi-Objective Approach for Network Reconfiguration of Distribution Systems

This paper presents an algorithm for network reconfiguration based on the heuristic rules and fuzzy multi-objective approach with an improved Fast Decoupled load flow algorithm. Multiple objectives are considered to minimize the real power loss, deviation in bus voltages, branch current violation and for load balancing among feeders, while subjected to a radial network structure in which all loads kept energized. These four objectives are modeled with fuzzy sets to evaluate their imprecise nature. Heuristic rules are also incorporated in the algorithm for drastically minimizing the number of tie-switch operations. An improved Fast Decoupled load flow algorithm with Single Matrix Model (FDC-SMM) has been proposed for distribution networks. The proposed algorithm is very effective in dealing with reconfiguration problems of single and multi-feeder networks Keywords: Multi-objective approach, Reconfiguration, Fuzzy set theory, Fast decoupled load flo