Data Driven Surrogate Based Optimization in the Problem Solving Environment WBCSim

Large scale, multidisciplinary, engineering designs are always difficult due to the complexity and dimensionality of these problems. Direct coupling between the analysis codes and the optimization routines can be prohibitively time consuming due to the complexity of the underlying simulation codes. One way of tackling this problem is by constructing computationally cheap(er) approximations of the expensive simulations, that mimic the behavior of the simulation model as closely as possible. This paper presents a data driven, surrogate based optimization algorithm that uses a trust region based sequential approximate optimization (SAO) framework and a statistical sampling approach based on design of experiment (DOE) arrays. The algorithm is implemented using techniques from two packages—SURFPACK and SHEPPACK that provide a collection of approximation algorithms to build the surrogates and three different DOE techniques—full factorial (FF), Latin hypercube sampling (LHS), and central composite design (CCD)—are used to train the surrogates. The results are compared with the optimization results obtained by directly coupling an optimizer with the simulation code. The biggest concern in using the SAO framework based on statistical sampling is the generation of the required database. As the number of design variables grows, the computational cost of generating the required database grows rapidly. A data driven approach is proposed to tackle this situation, where the trick is to run the expensive simulation if and only if a nearby data point does not exist in the cumulatively growing database. Over time the database matures and is enriched as more and more optimizations are performed. Results show that the proposed methodology dramatically reduces the total number of calls to the expensive simulation runs during the optimization process

Zero Temperature Insulator-Metal Transition in Doped Manganites

We study the transition at T=0 from a ferromagnetic insulating to a ferromagnetic metallic phase in manganites as a function of hole doping using an effective low-energy model Hamiltonian proposed by us recently. The model incorporates the quantum nature of the dynamic Jahn-Teller(JT) phonons strongly coupled to orbitally degenerate electrons as well as strong Coulomb correlation effects and leads naturally to the coexistence of localized (JT polaronic) and band-like electronic states. We study the insulator-metal transition as a function of doping as well as of the correlation strength U and JT gain in energy E_{JT}, and find, for realistic values of parameters, a ground state phase diagram in agreement with experiments. We also discuss how several other features of manganites as well as differences in behaviour among manganites can be understood in terms of our model.Comment: To be published in Europhysics Letter

Regeneration of Indian maize genotypes (Zea mays L.) from immature embryo culture through callus induction

Callus induction and regeneration ability of five maize genotypes UMI 757, UMI 615, UMI 112, UMI 285 and CO 1 and one promising maize hybrids COH(M) 5 were investigated using 14 days old immature embryos as explants. Callus induction depends on genotype, explants (age and size of explants), medium, type of auxin and their concentration. Explants grown on Murashige and Skoog (MS) medium supplemented with 1.5 mg/l 2, 4 - D (2,4 – dichloro phenoxy acetic acid), 0.3 mg/l kinetin with 30 g/l maltose showed the highest percentage of embryogenic callus induction. Among the six genotypes tested, COH(M) 5 maize hybrids have highest percentage of embryogenic calli. The embryogenic calli incubated on MS medium supplemented with 1.5 mg/l BAP (Benzyl Amino Purine), 0.2 mg/lNAA (Naphthalene Acetic Acid) with 1.0 mg/l kinetin was found to give the highest organogenesis response and regeneration of plantlets

PRELIMINARY IN VIVO EVALUATION OF ANTI-INFLAMMATORY ACTIVITIES OF VARIOUS SOLVENT EXTRACTS OF CADABA INDICA LAM ON CARRAGEENAN-INDUCED PAW EDEMA IN SWISS ALBINO RATS

ABSTRACTObjective: Among the invention of novel anti-inflammatory agents from modern research and drug development, the natural sources exist asevergreen to produce potential secondary metabolites that possess multiple efficacy against inflammatory mediators with no adverse reactions.Methods: Accordingly, Cadaba indica lam (Capparidaceae) produced the positive results for phenol, flavonoids, steroid, and saponins in preliminaryphytochemical screening and exhibited the potent anti-inflammatory activity (100 mg/kg, 200 mg/kg) by methanolic leaf extract against carrageenaninducedpawedemausing ratsindose-dependentmanner stayedcloser toreferencestandardindomethacin (25mg/kg)comparedtopetroleumetherandaqueous extract.Results: Thus, the plant C. indica lam might be considered to posses potential secondary metabolites against inflammatory agents and act as lead toisolation of novel therapeutic compounds.Conclusion: The phytochemical test indicates the presence of phenol, flavonoids, steroid, and saponins in leaf extract of C. indica may be known topossess anti-inflammatory property. The result of anti-inflammatory activity produced by the methanolic extract was threshold of isolation of biomolecules from the natural sources in diverse drug development in the near future being responsible for the pharmaceutical industries.Keywords: Preliminary phytochemical, Cadaba indica, Anti-inflammatory

A database management system for selection of steel

Selection of an ideal material for a given application will be a relatively simple matter, if perfect or near perfect materials are available. Such a material will have high strength, high toughness, good ductility and good fabricability. These properties would not necessarily be compatible in an existing material. Compromises and trade-offs among various properties become inevitable. On the other hand, infinite number of possible materials in various forms and its usage are so intertwined in all industries that a person can have no real comprehension of the characteristics of all the materials. A computer assistance either in the form of a software or a database is therefore unavoidable. A database is developed to assist in the selection of steels for scientific and engineering applications. A program is written in Foxpro to identify the ideal steel based on its tensile strength, elongation, toughness and hardness. The program can select the suitable steels and can generate the forging temper-ature, heat treatment procedure, etc. The input data are obtained from various handbooks and textbooks. A Pentium-586 with FOXPRO is used to build the prototype database management system in DOS environment. Human interface with the system is enhanced by the user-friendly menus. The database can be made compatible easily to a wide variety of micro, mini and mainframe computers

Personalisation and recommender systems in digital libraries

Widespread use of the Internet has resulted in digital libraries that are increasingly used by diverse communities of users for diverse purposes and in which sharing and collaboration have become important social elements. As such libraries become commonplace, as their contents and services become more varied, and as their patrons become more experienced with computer technology, users will expect more sophisticated services from these libraries. A simple search function, normally an integral part of any digital library, increasingly leads to user frustration as user needs become more complex and as the volume of managed information increases. Proactive digital libraries, where the library evolves from being passive and untailored, are seen as offering great potential for addressing and overcoming these issues and include techniques such as personalisation and recommender systems. In this paper, following on from the DELOS/NSF Working Group on Personalisation and Recommender Systems for Digital Libraries, which met and reported during 2003, we present some background material on the scope of personalisation and recommender systems in digital libraries. We then outline the working group’s vision for the evolution of digital libraries and the role that personalisation and recommender systems will play, and we present a series of research challenges and specific recommendations and research priorities for the field

2,3-dihydroxybenzoic acid decarboxylase from Aspergillus niger: a novel decarboxylase

2,3-Dihydroxybenzoic acid decarboxylase, the last enzyme in the fungal metabolism of indole to catechol, catalyzes the non-oxidative decarboxylation of 2,3-dihydroxybenzoic acid to catechol. Unlike most other decarboxylases, this enzyme does not require a cofactor, underlining the importance of active-site residues in the reaction mechanism. Earlier studies from this laboratory [Kamath, A. V., Appaji Rao, N. & Vaidyanathan, C. S. (1989) Biochem. Biophys. Res. Commun. 165, 20-261, have shown that the sulfhydryl agent N-ethylmaleimide (MalNEt) inactivated the enzyme by modifying a single class of cysteine residues and that this inactivation was prevented in the presence of salicylate, a substrate analogue. In the present study, this essential cysteine residue has been identified by specific labelling with [14C]- MalNEt using the differential labelling technique. The stoichiometry of incorporation of [I4C]MalNEt was approximately one/subunit of the homotetrameric protein. The peptide bearing this reactive cysteine residue was isolated by tryptic digestion of the differentially labelled enzyme and subsequent reverse-phase chromatography of the peptide mixture. The sequence of the major radioactive peptide that was identified to be the active-site peptide, was LLGLAETCK. A search for sequences similar to this active-site peptide indicated that this sequence was probably unique to the decarboxylase under study. A partial primary structure map constructed from the sequences of peptides derived from enzymic cleavage of the protein using endoproteinase Glu-C and trypsin did not share any significant sequence similarity with sequences reported in the database, again suggesting the uniqueness of the enzyme. This is the first report on the active-site peptide and the partial primary structure of a non-oxidative decarboxylase catalyzing the removal of a carboxyl group from an aromatic nucleus

Effect of harmones on callus induction in Maize (Zea mays L.)

Callus induction from explants is a critical process in regeneration, micropropagation and transformation of maize (Zea mays L.) plants. Formation of callus from plant tissues on culture is affected by several factors. This study revealed to establish the effect of genotype, source of explants and auxin concentration on callus induction from five genotypes UMI 757 (G1), UMI 615 (G2), UMI 112 (G3), UMI 285 (G4) and CO 1 (G5) and one hybrid CO H (M) 5 (G6). Callus induction of the six maize varieties was investigated using immature embryos (E1), leaf bits (E2), root tips (E3), hypocotyls (E4) and seeds (E5) as explants with different concentrations of hormones. In this study, immature embryo was taken from 10 to 12 days after pollination (DAP) to get maximum response. The highest percentage of callus induction was observed (99.10) in immature embryo culture and seed culture gave the highest percentage of rhizogenic callus formation when compare to immature embryo. Among the genotypes tested, CO H (M) 5 recorded the highest callus induction percentage on (2D2K2) medium composition