346 research outputs found
Applications of nanomaterials in enantioseparation and related techniques
No full textChirality is an important, universal phenomenon in nature. For the in-depth study of pharmacology and biology, efficient enantioselective technologies are indispensable. Nanomaterials with large surface-to-volume ratio and specific physical and chemical properties have demonstrated great potential in chiral discrimination. Many publications show that utilization of nanomaterials could improve the selectivity, the stability and the efficiency of enantioseparation. This review summarizes the applications of various enantioselective nanomaterials, including mesoporous silica, organic polymers, metal-organic frameworks, metal nanomaterials, magnetic nanomaterials, carbon nanotubes and well-oriented chiral nanolayers. After proper preparation and modification, these functionalized nanomaterials are effective for chiral separation through their specific enantioselective adsorption, especially when they are used as stationary or pseudo-stationary phases in chiral chromatographic separation, such as thin-layer chromatography, high-performance liquid chromatography, gas chromatography and capillary electrophoresis. (c) 2012 Elsevier Ltd. All rights reserved.Chemistry, AnalyticalSCI(E)16ARTICLE,SI195-2063
Immobilization-free DNA-based homogeneous electrochemical biosensors
No full textDNA is an excellent biomaterial for building biosensors utilizing diverse DNA interactions with a broad range of biomolecules and chemical compounds. DNA-based electrochemical biosensors have been successfully used in numerous applications with advantages of rapid detection, high sensitivity and low cost. Typical DNA-based electrochemical biosensors require an immobilization step of DNA probe as the biological recognition element, which always suffers from time-consuming and labor-intensive electrode pretreatment and immobilization process, expensive chemical modification, lower reactivity, and complicated operation. Immobilization-free DNA-based electrochemical biosensors can provide powerful complementary tools and novel design strategies for traditional electrochemical DNA biosensors. They would be advantageous in some ways, such as low cost, easy operation, and time saving. More importantly, the homogeneous reaction could increase the reliability and reproducibility of electrochemical sensor without the immobilization step. This review introduces multiple immobilization-free strategies for developing DNA-based homogeneous electrochemical biosensors, aiming at compensating for the deficiencies of heterogeneous modes. The main signal readout modes and signal enhancement strategies will be discussed separately. Additionally, the burgeoning applications combined with miniaturization of electrochemical devices will be highlighted. (C) 2016 Elsevier B.V. All rights reserved
Replication data for: India (2006): HIV/AIDS TRaC Study Evaluating Consistent Condom Use among Male Clients of Female Commercial Sex Workers in Andhra Pradesh, Karnataka, Maharashtra and Tamil Nadu First Round
No full textA cross sectional population based survey called a Behavior Change Impact Survey (BCIS-I), among male clients of female commercial sex workers was conducted in May 2006. The representative sample of 2,401 male clients of female commercial sex workers, randomly recruited from the high risk areas of project towns in the state of Andhra Pradesh, Tamil Nadu, Karnataka and Maharashtra were interviewed using a structured questionnaire while following the multi-stage cluster sampling process. Basic demographic information was collected in addition to media habits and media use, behavior, hypothesized determinants of behavior and levels of exposure to interventions. A pilot study was undertaken prior to the main study to conduct reliability analysis for the measurement of the determinants of behavior and to refine the measurement tool for the final survey
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A description of the expanded test problems in the TRAC-P standard test matrix
No full textThis report describes the expanded set of test problems that were created to augment the existing Transient Reactor Analysis Code (TRAC)-P standard matrix of test problems. The expanded test problems were created to support the TRAC-P modernization effort. In most cases, these test problems were modified or expanded versions of problems in the TRAC Standard Test Matrix. A problem description is included for each problem added to the Standard Test Matrix. In this description, the details regarding modifications of the original test problem are included, as well as the observed problem results. This expanded test set will be used to verify that the predicted results for the modernized version of TRAC-M/f90 are null relative to the archival version of TRAC-P/MOD2 (Ver. 5.4.25), the latter being the base version on which work on the modernized code began. The problems described in this document increase the percentage of executable source coding that is activated when the Standard Test Matrix is run from 71% to 83.5%. A brief review of the characteristics of the portions of the source code that are not activated when running the expanded Standard Test Set also is provided. With a few exceptions, the author has concluded that the cost to increase the fraction of coding activated by the Standard Test Set further is high relative to the increased coverage that can be attained. Therefore, the author recommends that this activity be concluded
Replication data for: Nepal (2007): Malaria TRaC and Net Coverage Survey in Five Districts of Nepal - Phase II of the Malaria Prevention Program
No full textThe purpose of the TRaC Malaria Phase II was to answer the question: Among the target population living in the malaria affected districts of Nepal, what determines the use of LLINs in terms of opportunity, ability and motivation? Specifically, the research objectives were to identify and describe one or more target groups in terms of: a. Risk; b. Behavior (Use of LLINs); c. Behavioral determinants (opportunity, ability and motivational(OAM) characteristics); and d. Population characteristics, including media habits; TRaC Malaria Phase II was conducted in July-September 2007 with a total of 2,200 respondents in five malaria prone districts in Nepal, via a structured questionnaire interview process. A multi-stage cluster sampling approach was used to draw a sample of households with children under five years of age living in the program area of five malaria affected districts. The five districts include: Jhapa, Kanchanpur, Kavre, Mahottari, and Sindhuli. PSI/Nepal used the PSI TRaC methodology, which is designed to provide actionable evidence for decision making. The TRaC survey systematically and repeatedly measures levels and trends of indicators such as behaviors, behavioral determinants and population characteristics. The framework for development and construction of the variables for the behavioral determinants is based on the PSI Behavi
or Change Framework (Annex 2)
Parametrizing the Reionization History with the Redshift Midpoint, Duration, and Asymmetry
No full textOut-of-core hydrodynamic simulations of cosmological structure formation
No full textAstrophysical and cosmological structure formation are challenging problems because they involve dynamical and hydrodynamical processes that can span a large range in scale, mass, and energy. Hydrodynamic and N-body simulations are powerful tools with which to solve the nonlinear physics, and their continuing development and application is the focus of this thesis. I present a new approach to Eulerian computational fluid dynamics that is designed to work at high Mach numbers encountered in astrophysical simulations. The Eulerian conservation equations are solved in an adaptive frame moving with the fluid where Mach numbers are minimized. The Moving Frame code separately tracks local and bulk flow components, allowing thermodynamic variables to be accurately calculated in both subsonic and supersonic fluid. This thesis includes the first astrophysical application of Eulerian hydrodynamic simulations to model the formation of blue stragglers through stellar mergers. The off-axis collision of equal mass stars produces a single merger remnant. The merger of n = 3 polytropes results in substantial chemical mixing throughout the remnant, while the merger of realistic M = 0.8 M odot; main sequence stars produces significant mixing only outside of the core. The Out-of-core Hydro code is applied to running the largest Eulerian hydrodynamic simulation to date for studying the thermal history of the high redshift 3 le; z le; 7 intergalactic medium. The temperature-density and gas-dark matter density relations, as well as the scatter in these relations, are robustly quantified. Reionization and shock heating are observed to influence the temperature of the photoionized gas. An out-of-core hydrodynamic code has been developed for high resolution cosmological simulations. Out-of-core computation refers to the technique of using disk space as virtual memory and transferring data in and out of main memory at high I/O bandwidth. The code is based on a two-level mesh scheme where short-range physics is solved on a high-resolution, localized mesh while long-range physics is captured on a lower resolution, global mesh. Furthermore, a parallel particle-mesh N-body code is applied to simulating the clustering of dark matter halos. The PMFAST simulations show that that several bias parameters are consistent with being scale-invariant, a useful property for doing cosmology with galaxy clustering.Ph.D
PENGARUH KUALITAS PELAYANAN TERHADAP KEPUASAN PELANGGAN TRAC ASTRA Rent A Car BANDUNG
No full textTypes of research used in this study is the survey method. This study is correlational. In this study population is used TRAC ASTRA customer Rent a Car Bandung. While the sample of this research is the customer TRAC Astra Rent a Car London to represent the population. In determining the sample, the authors use the sampling is non-probability sampling with accidental sampling technique, this technique is used because of accidental random samples taken are not unlimited and researchers assume that consumers have the same intentions. That samples can be taken is 100 respondents. For data analysis the authors using Spearman rank correlation analysis method, intended for both variables are measured in ordinal scale as well as to determine how strong the relationship, also the direction of the relationship between the independent variable on the dependent variable service quality customer satisfaction. Respondents to the quality of service at PT. TRAC Astra Rent a Car Bandung can be said AGREE, thus it can be stated that the respondents to the question regarding the quality of service at PT. TRAC Astra Rent a Car Bandung WELL said, because the average value of the entire statement is at 3.60 which is in the interval from 3.40 to 4.19. Respondents regarding customer satisfaction at PT. TRAC Astra Rent a Car Bandung can be said AGREE, thus it can be stated that the respondents questions about customer satisfaction at PT. TRAC Astra Rent a Car Bandung WELL said, because the average value of the entire statement is at 3.70 which is in the interval from 3.40 to 4.19. Based on the calculation of correlation coefficients using the Spearman Rank correlation obtained a value of 00.694. Statistical inference, there is a positive and direct relationship between quality of service (X) to customer satisfaction (Y) at PT. TRAC Astra Rent a Car Bandung. Determination coefficient test results influence of service quality on customer satisfaction with PT. TRAC Astra Rent a Car London is at 48.1% while the remaining 51.9% is influenced by other variables not examined in this study. Based on the obtained t significance test of 13.260, while ttable 0.195, t greater than t table (13.260> 0.195) and hypothesis testing based on criteria, ie if t> t table, then Ho is rejected and Hi is accepted. Thus the author proposed that the hypothesis, which is: "Quality of Service (X) The Customer Satisfaction (Y) at PT. TRAC Astra Rent a Car Bandung "Acceptable
Comparison of reionization models: radiative transfer simulations and approximate, seminumeric models
No full textWe compare the predictions of four different algorithms for the distribution of ionized gas during the Epoch of Reionization. These algorithms are all used to run a 100Mpch-1 simulation of reionization with the same initial conditions. Two of the algorithms are state-of-the-art ray-tracing radiative transfer codes that use disparate methods to calculate the ionization history. The other two algorithms are fast but more approximate schemes based on iterative applications of a smoothing filter on the underlying source and density fields. We compare these algorithms' resulting ionization and 21-cm fields using several different statistical measures. The two radiative transfer schemes are in excellent agreement judging by the power spectra of both the ionization fields and the 21-cm emission fields (agreeing to better than 10 per cent) and are in good agreement with the analytic schemes (better than 50 per cent) over the range of ionized fractions and wavevectors we compare (Mpc-1). This agreement suggests that the different approximations involved in the ray-tracing algorithms are sensible and that seminumerical schemes provide a numerically inexpensive, yet fairly accurate, description of the reionization process. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS
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