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First-principles study of crystallographic slip modes in Ļ-Zr.
We use first-principles density functional theory to study the preferred modes of slip in the high-pressure Ļ phase of Zr. The generalized stacking fault energy surfaces associated with shearing on nine distinct crystallographic slip modes in the hexagonal Ļ-Zr crystal are calculated, from which characteristics such as ideal shear stress, the dislocation Burgers vector, and possible accompanying atomic shuffles, are extracted. Comparison of energy barriers and ideal shear stresses suggests that the favorable modes are prismatic ćcć, prismatic-II [Formula: see text] and pyramidal-II ćcā+āać, which are distinct from the ground state hexagonal close packed Ī± phase of Zr. Operation of these three modes can accommodate any deformation state. The relative preferences among the identified slip modes are examined using a mean-field crystal plasticity model and comparing the calculated deformation texture with the measurement. Knowledge of the basic crystallographic modes of slip is critical to understanding and analyzing the plastic deformation behavior of Ļ-Zr or mixed Ī±-Ļ phase-Zr
Freezing characteristics of tropical fishes 2. Tilapia (Tilapia mosambica)
Tilapia from fresh water and brackish water-sources behaved differently during iced and frozen storage. The former showed an ice storage shelf life of about 13 days while the latter showed signs of spoilage beyond 10 days. In their respective freezing characteristics, the samples from the two sources exhibited far more significant variations. The fresh water type iced for 13 days preserved well for over 24 weeks when frozen and kept at a temperature of -18Ā° C, while the brackish water variety held in ice for 10 days and subsequently frozen gave a shelf life of only 8 weeks under similar conditions
Studies on isolation of salmonella from sea foods 1. Comparison of enrichment and selective media for recovery of salmonellae from fish
Three enrichment broths and six plating media were compared for efficiency of detection Salmonella in the presence of numbers of Coliforms (10super(5)/ml) and proteus (10super(3)/ml) from artificially inoculated fish samples. Recovery experiments Salmonella anatum, S. typhimurium and S. enteritidis indicated that the two enrichment broths Dulcitol Selinite (DSE) and Selinite Cystine (SC) were equally efficient. Further, the viability of Salmonella, inoculated into fish muscle and kept at 4Ā°C for 48 hours, was found to be not affected by the low temperature storage. Selective plating media like Xylose Lysine Deoxycholate agar (XLD), Brilliant Green Sulphadiazine agar (BGS) and Brilliant Green agar (BG) were found to be superior in performance to Salmonella-Shigella agar: (SS) and Bismuth Sui phite agar (BiS)
Technological aspects of preservation and processing of edible shell fish 2. Influence of season on the chemical composition of crab (Scylla serrata)
The purpose of this communication is to bring out the influence of season on the chemical composition of crab, covering a period of 2 years. Changes in moisture, protein, water extractable nitrogen, non-protein nitrogen, glycogen, lactic acid, fat and free amino acid composition of crab meat have been reported on a monthly basis
Classification and Selection of Biomarkers in Genomic Data Using LASSO
High-throughput gene expression technologies such as microarrays have been utilized in a variety of scientific applications. Most of the work has been done on assessing univariate associations between gene expression profiles with clinical outcome (variable selection) or on developing classification procedures with gene expression data (supervised learning). We consider a hybrid variable selection/classification approach that is based on linear combinations of the gene expression profiles that maximize an accuracy measure summarized using the receiver operating characteristic curve. Under a specific probability model, this leads to the consideration of linear discriminant functions. We incorporate an automated variable selection approach using LASSO. An equivalence between LASSO estimation with support vector machines allows for model fitting using standard software. We apply the proposed method to simulated data as well as data from a recently published prostate cancer study
Entanglement transitions in random definite particle states
Entanglement within qubits are studied for the subspace of definite particle
states or definite number of up spins. A transition from an algebraic decay of
entanglement within two qubits with the total number of qubits, to an
exponential one when the number of particles is increased from two to three is
studied in detail. In particular the probability that the concurrence is
non-zero is calculated using statistical methods and shown to agree with
numerical simulations. Further entanglement within a block of qubits is
studied using the log-negativity measure which indicates that a transition from
algebraic to exponential decay occurs when the number of particles exceeds .
Several algebraic exponents for the decay of the log-negativity are
analytically calculated. The transition is shown to be possibly connected with
the changes in the density of states of the reduced density matrix, which has a
divergence at the zero eigenvalue when the entanglement decays algebraically.Comment: Substantially added content (now 24 pages, 5 figures) with a
discussion of the possible mechanism for the transition. One additional
author in this version that is accepted for publication in Phys. Rev.
Empirical Bayes Identication of Tumor Progression Genes from Microarray Data
The use of microarray data has become quite commonplace in medical and scientific experiments. We focus here on microarray data generated from cancer studies. It is potentially important for the discovery of biomarkers to identify genes whose expression levels correlate with tumor progression. In this article, we propose a simple procedure for the identification of such genes, which we term tumor progression genes. The first stage involves estimation based on the proportional odds model. At the second stage, we calculate two quantities: a q -value, and a shrinkage estimator of the test statistic is constructed to adjust for the multiple testing problem. The relationship between the proposed method with the false discovery rate is studied. The proposed methods are applied to data from a prostate cancer microarray study. (Ā© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55946/1/68_ftp.pd
Encryption Quality and Performance Analysis of GKSBC Algorithm
In the age of intensive data exchanges, security of data poses a major challenge to the existing communication arrangement. In this context the evolution and evaluation of new encryption system is inextricably linked to the process of realizing ever increasing network security needs. Recently a Generalized Key Scheme in a Block Cipher Algorithm (GKSBC) is found to be robust in cryptanalysis and the result of key sensitivity analysis was found satisfactory. This study compares GKSBC with the class of block cipher algorithms viz., RC6, AES and Blowfish, and presents a performance evaluation. To assess the encryption quality two measures viz., Encryption Quality measure and Correlation analysis is applied. Thorough experimental tests with detailed analysis showed the high quality and comparative efficiency of GKSBC algorithm. Keywords: symmetric, generalized, throughput, encryption, correlation
Integrated Approach to Design and Manufacture of Gas Turbine Components Based on Group Theory
This paper deals with a new method that provides an integrated approach to design and manufacture of gas turbine components by using the group theory and customising standard computer aided design and manufacturing system. With this approach time consuming and iterative design procedure and process planning are automated and become more efficient. Due to the intricate and diverse nature of gas turbine components, grouping them is not easy as in other industries. A possible way of grouping the gas turbine components based on design and manufacturing attributes on a broad basis is presented. A case study of high pressure turbine disc is included with illustrations for design and process planning of this component. The proposed system is implemented on a personal computer and offers an alternate solution to sophisticated and expensive main frame based systems
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