Modification of DNA radiolysis by DNA-binding proteins: structural aspects

Formation of specific complexes between proteins and their cognate DNA modulates the yields and the location of radiation damage on both partners of the complex. The radiolysis of DNA-protein complexes is studied for: (1) the Escherichia coli lactose operator-repressor complex, (2) the complex between DNA bearing an analogue of an abasic site and the repair protein Fpg of Lactococcus lactis. Experimental patterns of DNA damages are presented and compared to predicted damage distribution obtained using an improved version of the stochastic model RADACK. The same method is used for predicting the location of damages on the proteins. At doses lower than a threshold that depends on the system, proteins protect their specific binding site on DNA while at high doses, the studied complexes are disrupted mainly through protein damage. The loss of binding ability is the functional consequence of the amino-acids modification by OH* radicals. Many of the most probably damaged amino acids are essential for the DNA-protein interaction and within a complex are protected by DNA.     

Sizzle: A standards-based end-to-end security architecture for the embedded Internet

According to popular perception, public-key cryptography is beyond the capabilities of highly constrained, “mote”-like, embedded devices. We show that elliptic curve cryptography not only makes public-key cryptography feasible on these devices, it allows one to create a complete secure web server stack that runs efficiently within very tight resource constraints. Our small-footprint HTTPS stack, nicknamed Sizzle, has been implemented on multiple generations of the Berkeley/Crossbow motes where it runs in less than 4 KB of RAM, completes a full SSL handshake in 1 s (session reuse takes 0.5 s) and transfers 1 KB of application data over SSL in 0.4 s. Sizzle is the world’s smallest secure web server and can be embedded inside home appliances, personal medical devices, etc., allowing them to be monitored and controlled remotely via a web browser without sacrificing end-to-end security.     

Volatile degradation products ofl-dehydroascorbic acid

European Food Research and Technology - Volatile degradation products were isolated from a solution ofl-dehydroascorbic acid in phosphate buffers solution of pH 2, 4, 6 and 8 heated under reflux...     

Polynomial time algorithm for an optimal stable assignment with multiple partners

This paper considers the many-to-many version of the stable marriage problem where each man and woman has a strict preference ordering on the members of the opposite sex that he or she considers acceptable. Further, each man and woman wishes to be matched to as many acceptable partners as possible, up to his or her specified quota. In this setup, a polynomial time algorithm for finding a stable matching that minimizes the sum of partner ranks across all men and women is provided. It is argued that this sum can be used as an optimality criterion for minimizing total dissatisfaction if the preferences over partner-combinations satisfy a no-complementarities condition. The results in this paper extend those already known for the one-to-one version of the problem.     

Magnetic iron oxide nanoparticles immobilized on microporous molecular sieves as efficient porous catalyst for photodegradation,transesterification and esterification reactions

Journal of Porous Materials - Magnetic iron oxide nanoparticles were immobilized on microporous molecular sieves (13X) via a plant extract mediated green synthesis method. The prepared material was...     

A Disjunctive Model for Scheduling in a Manufacturing and Packing Facility with Intermediate Storage

The problem considered in this paper deals with the short term scheduling of a two stage continuous process with intermediate storage tanks. The major scheduling decisions in this problem are: a) the assignment of orders to various storage tanks; b) the sequence of orders in each unit; c) the timing of various operations in different stages. The problem is highly combinatorial in nature. The major challenge is to develop strong integer programming formulations and to devise efficient solution techniques. An initial model is presented in the form of a disjunctive program which is later transformed to a Mixed Integer Linear Programming (MILP) problem. A number of example problems are solved which highlight the limitations of this model as the number of orders increases. A heuristic based on partial preordering is considered which solves industrial sized problems very quickly. The objective function values for the heuristic solutions are within 7% of the optimal values.     

Performance enhancement of photovoltaic modules by nanofluid cooling: A comprehensive review

Only 15-20% of solar radiation incident on the photovoltaic (PV) cells is utilized which further reduces due to the rise in the temperature of the PV module and it also degrades the lifespan of the PV module. Therefore, numerous attempts were made to reduce this rising temperature of the PV module and different cooling techniques were employed. Nanofluid cooling is one of the potential cooling techniques for lowering the temperature of the PV module and augmenting the heat transfer by increasing the thermal conductivity of the nanofluid relative to the base fluid (BF). The experimental and numerical studies related to the cooling of PV cells with nanofluids have been reviewed. It was found that the heat transfer from the back of the PV module is enhanced with the augmentation in the concentration of nanoparticle in BF; however, some studies also demonstrate that the enhancement in the heat transfer also depends upon other factors such as the geometry at the rear of the PV module, nanoparticle material, nanoparticle size, BF, ambient conditions, etc. This review article also demonstrates the various issues with nanofluids such as instability, technological difficulties, high system costs, and the impossibility of finding a viable operational design which creates a barrier in the commercialization of the nanofluid cooling technique for PV modules.