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1

Projector Method: theory and examples  

SciTech Connect

The Projector Method technique for numerically analyzing lattice gauge theories was developed to take advantage of certain simplifying features of gauge theory models. Starting from a very general notion of what the Projector Method is, the techniques are applied to several model problems. After these examples have traced the development of the actual algorithm from the general principles of the Projector Method, a direct comparison between the Projector and the Euclidean Monte Carlo is made, followed by a discussion of the application to Periodic Quantum Electrodynamics in two and three spatial dimensions. Some methods for improving the efficiency of the Projector in various circumstances are outlined. 10 refs., 7 figs. (LEW)

Dahl, E.D.

1985-01-01

2

APPLICATION OF SPECTROSCOPIC METHODS FOR THE AUTOMATION OF OIL PALM CULTURE APPLICATION OF SPECTROSCOPIC METHODS  

E-print Network

APPLICATION OF SPECTROSCOPIC METHODS FOR THE AUTOMATION OF OIL PALM CULTURE 1 APPLICATION OF SPECTROSCOPIC METHODS FOR THE AUTOMATION OF OIL PALM CULTURE LAURA B WILLIS*; GUSTAVO A GIL**; HARRY L T LEE: Raman, UV fluorescence, spectroscopy, cytometry, glucose. Date received: 31 July 2007; Sent for revision

Sinskey, Anthony J.

3

An Introduction To Computer Simulation Methods Examples  

NSDL National Science Digital Library

Ready to run Launcher package containing examples for An Introduction to Computer Simulation Methods by Harvey Gould, Jan Tobochnik, and Wolfgang Christian. Source code for examples in this textbook is distributed in the Open Source Physics Eclipse Workspace.

Christian, Wolfgang; Gould, Harvey; Tobochnik, Jan

2008-05-17

4

Mass spectroscopic apparatus and method  

DOEpatents

The disclosure is directed to a method and apparatus for ionization modulated mass spectrometric analysis. Analog or digital data acquisition and processing can be used. Ions from a time variant source are detected and quantified. The quantified ion output is analyzed using a computer to provide a two-dimensional representation of at least one component present within an analyte.

Bomse, David S. (Santa Fe, NM); Silver, Joel A. (Santa Fe, NM); Stanton, Alan C. (Santa Fe, NM)

1991-01-01

5

Combined method to extract spectroscopic information  

E-print Network

Spectroscopic factors (SF) play an important role in nuclear physics and astrophysics. The traditional method of extracting SF from direct transfer reactions suffers from serious ambiguities. We discuss a modified method which is based on including the asymptotic normalization coefficient (ANC) of the overlap functions into the transfer analysis. In the modified method the contribution of the external part of the reaction amplitude, typically dominant, is fixed and the SF is determined from fitting the internal part. We illustrate the modified method with $(d,p)$ reactions on ${}^{208}{\\rm Pb}, {}^{12}{\\rm C}$, and ${}^{84}{\\rm Se}$ targets at different energies. The modified method allows one to extract the SF, which do not depend on the shape of the single-particle nucleon-target interaction, and has the potential of improving the reliability and accuracy of the structure information. This is specially important for nuclei on dripline, where not much is known.

A. M. Mukhamedzhanov; F. M. Nunes

2005-05-16

6

Spectroscopic chemical analysis methods and apparatus  

NASA Technical Reports Server (NTRS)

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

Hug, William F. (Inventor); Reid, Ray D. (Inventor); Bhartia, Rohit (Inventor)

2013-01-01

7

Spectroscopic Chemical Analysis Methods and Apparatus  

NASA Technical Reports Server (NTRS)

This invention relates to non-contact spectroscopic methods and apparatus for performing chemical analysis and the ideal wavelengths and sources needed for this analysis. It employs deep ultraviolet (200- to 300-nm spectral range) electron-beam-pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor lightemitting devices, and hollow cathode metal ion lasers. Three achieved goals for this innovation are to reduce the size (under 20 L), reduce the weight [under 100 lb (.45 kg)], and reduce the power consumption (under 100 W). This method can be used in microscope or macroscope to provide measurement of Raman and/or native fluorescence emission spectra either by point-by-point measurement, or by global imaging of emissions within specific ultraviolet spectral bands. In other embodiments, the method can be used in analytical instruments such as capillary electrophoresis, capillary electro-chromatography, high-performance liquid chromatography, flow cytometry, and related instruments for detection and identification of unknown analytes using a combination of native fluorescence and/or Raman spectroscopic methods. This design provides an electron-beampumped semiconductor radiation-producing method, or source, that can emit at a wavelength (or wavelengths) below 300 nm, e.g. in the deep ultraviolet between about 200 and 300 nm, and more preferably less than 260 nm. In some variations, the method is to produce incoherent radiation, while in other implementations it produces laser radiation. In some variations, this object is achieved by using an AlGaN emission medium, while in other implementations a diamond emission medium may be used. This instrument irradiates a sample with deep UV radiation, and then uses an improved filter for separating wavelengths to be detected. This provides a multi-stage analysis of the sample. To avoid the difficulties related to producing deep UV semiconductor sources, a pumping approach has been developed that uses ballistic electron beam injection directly into the active region of a wide bandgap semiconductor material.

Hug, William F.; Reid, Ray D.

2012-01-01

8

Advances in spectroscopic methods for quantifying soil carbon  

USGS Publications Warehouse

The current gold standard for soil carbon (C) determination is elemental C analysis using dry combustion. However, this method requires expensive consumables, is limited by the number of samples that can be processed (~100/d), and is restricted to the determination of total carbon. With increased interest in soil C sequestration, faster methods of analysis are needed, and there is growing interest in methods based on diffuse reflectance spectroscopy in the visible, near-infrared or mid-infrared spectral ranges. These spectral methods can decrease analytical requirements and speed sample processing, be applied to large landscape areas using remote sensing imagery, and be used to predict multiple analytes simultaneously. However, the methods require localized calibrations to establish the relationship between spectral data and reference analytical data, and also have additional, specific problems. For example, remote sensing is capable of scanning entire watersheds for soil carbon content but is limited to the surface layer of tilled soils and may require difficult and extensive field sampling to obtain proper localized calibration reference values. The objective of this chapter is to discuss the present state of spectroscopic methods for determination of soil carbon.

Reeves, James B., III; McCarty, Gregory W.; Calderon, Francisco; Hively, W. Dean

2012-01-01

9

Experimental Mathemataics: Examples, Methods andImplications  

SciTech Connect

Recent years have seen the flowering of ''experimental'' mathematics, namely the utilization of modern computer technology as an active tool in mathematical research. This development is not limited to a handful of researchers, nor to a handful of universities, nor is it limited to one particular field of mathematics. Instead, it involves hundreds of individuals, at many different institutions, who have turned to the remarkable new computational tools now available to assist in their research, whether it be in number theory, algebra, analysis, geometry or even topology. These tools are being used to work out specific examples, generate plots, perform various algebraic and calculus manipulations, test conjectures, and explore routes to formal proof. Using computer tools to test conjectures is by itself a major time saver for mathematicians, as it permits them to quickly rule out false notions.

Bailey, David H.; Borwein, Jonathan M.

2005-01-31

10

Standards in the Methods Class, an Example.  

ERIC Educational Resources Information Center

Shares an experience from a mathematics methods course for elementary teachers that used concrete materials to teach the concept of rounding in different bases. Discusses how this experience modeled recommendations by the NCTM "Professional Teaching Standards" in creating classroom climate and conducting discussion. (MDH)

Wesson, James B.; Lawhorn, Cynthia

1992-01-01

11

Mixed Methods Sampling: A Typology with Examples  

ERIC Educational Resources Information Center

This article presents a discussion of mixed methods (MM) sampling techniques. MM sampling involves combining well-established qualitative and quantitative techniques in creative ways to answer research questions posed by MM research designs. Several issues germane to MM sampling are presented including the differences between probability and…

Teddlie, Charles; Yu, Fen

2007-01-01

12

Spectroscopic studies of protein folding: Linear and nonlinear methods  

PubMed Central

Although protein folding is a simple outcome of the underlying thermodynamics, arriving at a quantitative and predictive understanding of how proteins fold nevertheless poses huge challenges. Therefore, both advanced experimental and computational methods are continuously being developed and refined to probe and reveal the atomistic details of protein folding dynamics and mechanisms. Herein, we provide a concise review of recent developments in spectroscopic studies of protein folding, with a focus on new triggering and probing methods. In particular, we describe several laser-based techniques for triggering protein folding/unfolding on the picosecond and/or nanosecond timescales and various linear and nonlinear spectroscopic techniques for interrogating protein conformations, conformational transitions, and dynamics. PMID:22109973

Serrano, Arnaldo L; Waegele, Matthias M; Gai, Feng

2012-01-01

13

Scanning Tunneling Microscopy methods for spectroscopic imaging of subsurface interfaces  

NASA Technical Reports Server (NTRS)

A new method for spatially-resolved, spectroscopic investigation of subsurface interface structure has been developed. The method, Ballistic Electron Emission Microscopy (BEEM), is based on Scanning Tunneling Microscopy (STM) techniques. BEEM combines STM vacuum tunneling with unique ballistic electron spectroscopy capabilities. BEEM enables, for the first time, direct imaging of subsurface interface electronic properties with nanometer spatial resolution. STM topographic images of surface structure and BEEM images of subsurface properties are obtained simultaneously. BEEM capabilities are demonstrated by investigation of important metal-semiconductor interfaces.

Bell, L. D.; Kaiser, W. J.

1988-01-01

14

Mixed Methods in Nursing Research : An Overview and Practical Examples  

PubMed Central

Mixed methods research methodologies are increasingly applied in nursing research to strengthen the depth and breadth of understanding of nursing phenomena. This article describes the background and benefits of using mixed methods research methodologies, and provides two examples of nursing research that used mixed methods. Mixed methods research produces several benefits. The examples provided demonstrate specific benefits in the creation of a culturally congruent picture of chronic pain management for American Indians, and the determination of a way to assess cost for providing chronic pain care.

Doorenbos, Ardith Z.

2014-01-01

15

Spectroscopic Methods of Remote Sensing for Vegetation Characterization  

NASA Astrophysics Data System (ADS)

Imaging spectroscopy (IS), often referred to as hyperspectral remote sensing, is one of the latest innovations in a very long history of spectroscopy. Spectroscopic methods have been used for understanding the composition of the world around us, as well as, the solar system and distant parts of the universe. Continuous sampling of the electromagnetic spectrum in narrow bands is what separates IS from previous forms of remote sensing. Terrestrial imaging spectrometers often have hundreds of channels that cover the wavelength range of reflected solar radiation, including the visible, near-infrared (NIR), and shortwave infrared (SWIR) regions. In part due to the large number of channels, a wide variety of methods have been applied to extract information from IS data sets. These can be grouped into several broad classes, including: multi-channel indices, statistical procedures, full spectrum mixing models, and spectroscopic methods. Spectroscopic methods carry on the more than 150 year history of laboratory-based spectroscopy applied to material identification and characterization. Spectroscopic methods of IS relate the positions and shapes of spectral features resolved by airborne and spaceborne sensors to the biochemical and physical composition of vegetation in a pixel. The chlorophyll 680nm, water 980nm, water 1200nm, SWIR 1700nm, SWIR 2100nm, and SWIR 2300nm features have been the subject of study. Spectral feature analysis (SFA) involves isolating such an absorption feature using continuum removal (CR) and calculating descriptors of the feature, such as center position, depth, width, area, and asymmetry. SFA has been applied to quantify pigment and non-pigment biochemical concentrations in leaves, plants, and canopies. Spectral feature comparison (SFC) utilizes CR of features in each pixel's spectrum and linear regression with continuum-removed features in reference spectra in a library of known vegetation types to map vegetation species and communities. SFC has been applied to map the distributions of minerals in soils and rocks; however, its application to characterize vegetation cover has been less widespread than SFA. Using IS data and the USGS Processing Routines in IDL for Spectroscopic Measurements (PRISM; http://pubs.usgs.gov/of/2011/1155/), this talk will examine requirements for and limitations in applying SFA and SFC to characterize vegetation. A time series of Airborne Visible/InfraRed Imaging Spectrometer (AVIRIS) data collected in the marshes of Louisiana following the Deepwater Horizon oil spill will be used to examine the impact of varying leaf water content on the shapes of the SWIR 1700, 2100, and 2300 nm features and the implications of these changes on vegetation identification and biochemical estimation. The USGS collection of HyMap data over Afghanistan, the largest terrestrial coverage of IS data to date, will be used to demonstrate the characterization of vegetation in arid and semi-arid regions, in which chlorophyll absorption is often weak and soil and rock mineral absorption features overlap vegetation features. Hyperion data, overlapping the HyMap data, will be presented to illustrate the complications that arise when signal-to-noise is low. The benefits of and challenges to applying a spectroscopic remote sensing approach to imaging spectrometer data will be discussed.

Kokaly, R. F.

2013-12-01

16

Can the electronegativity equalization method predict spectroscopic properties?  

NASA Astrophysics Data System (ADS)

The electronegativity equalization method is classically used as a method allowing the fast generation of atomic charges using a set of calibrated parameters and provided knowledge of the molecular structure. Recently, it has started being used for the calculation of other reactivity descriptors and for the development of polarizable and reactive force fields. For such applications, it is of interest to know whether the method, through the inclusion of the molecular geometry in the Taylor expansion of the energy, would also allow sufficiently accurate predictions of spectroscopic data. In this work, relevant quantities for IR spectroscopy are considered, namely the dipole derivatives and the Cartesian Hessian. Despite careful calibration of parameters for this specific task, it is shown that the current models yield insufficiently accurate results.

Verstraelen, T.; Bultinck, P.

2015-02-01

17

GPU-Accelerated Method of Moments by Example: Monostatic Scattering  

Microsoft Academic Search

In this paper, we combine and extend two of our previous works to provide a more complete solution for the GPU acceleration of the Method of Moments, using CUDA by NVIDIA. To this end, the formulations of the original 1982 Rao-Wilton-Glisson paper are revisited, and the scattering analysis of a square PEC plate is considered as a simple example. One

E. Lezar; D. B. Davidson

2010-01-01

18

An empirical evaluation of three vibrational spectroscopic methods for detection of aflatoxins in maize.  

PubMed

Three commercially available vibrational spectroscopic techniques, including Raman, Fourier transform near infrared reflectance (FT-NIR), and Fourier transform infrared (FTIR) were evaluated to help users determine the spectroscopic method best suitable for aflatoxin analysis in maize (Zea mays L.) grain based on their relative efficiency and predictive ability. Spectral differences of Raman and FTIR spectra were more marked and pronounced among aflatoxin contamination groups than those of FT-NIR spectra. From the observations and findings in our current and previous studies, Raman and FTIR spectroscopic methods are superior to FT-NIR method in terms of predictive power and model performance for aflatoxin analysis and they are equally effective and accurate in predicting aflatoxin concentration in maize. The present study is considered as the first attempt to assess how spectroscopic techniques with different physical processes can influence and improve accuracy and reliability for rapid screening of aflatoxin contaminated maize samples. PMID:25466069

Lee, Kyung-Min; Davis, Jessica; Herrman, Timothy J; Murray, Seth C; Deng, Youjun

2015-04-15

19

Computation of spectroscopic factors with the coupled-cluster method  

E-print Network

We present a calculation of spectroscopic factors within coupled-cluster theory. Our derivation of algebraic equations for the one-body overlap functions are based on coupled-cluster equation-of-motion solutions for the ground and excited states of the doubly magic nucleus with mass number $A$ and the odd-mass neighbor with mass $A-1$. As a proof-of-principle calculation, we consider $^{16}$O and the odd neighbors $^{15}$O and $^{15}$N, and compute the spectroscopic factor for nucleon removal from $^{16}$O. We employ a renormalized low-momentum interaction of the $V_{\\mathrm{low-}k}$ type derived from a chiral interaction at next-to-next-to-next-to-leading order. We study the sensitivity of our results by variation of the momentum cutoff, and then discuss the treatment of the center of mass.

Ø. Jensen; G. Hagen; T. Papenbrock; D. J. Dean; J. S. Vaagen

2010-04-15

20

Using Crowdsourcing to Evaluate Published Scientific Literature: Methods and Example  

PubMed Central

Systematically evaluating scientific literature is a time consuming endeavor that requires hours of coding and rating. Here, we describe a method to distribute these tasks across a large group through online crowdsourcing. Using Amazon's Mechanical Turk, crowdsourced workers (microworkers) completed four groups of tasks to evaluate the question, “Do nutrition-obesity studies with conclusions concordant with popular opinion receive more attention in the scientific community than do those that are discordant?” 1) Microworkers who passed a qualification test (19% passed) evaluated abstracts to determine if they were about human studies investigating nutrition and obesity. Agreement between the first two raters' conclusions was moderate (??=?0.586), with consensus being reached in 96% of abstracts. 2) Microworkers iteratively synthesized free-text answers describing the studied foods into one coherent term. Approximately 84% of foods were agreed upon, with only 4 and 8% of ratings failing manual review in different steps. 3) Microworkers were asked to rate the perceived obesogenicity of the synthesized food terms. Over 99% of responses were complete and usable, and opinions of the microworkers qualitatively matched the authors' expert expectations (e.g., sugar-sweetened beverages were thought to cause obesity and fruits and vegetables were thought to prevent obesity). 4) Microworkers extracted citation counts for each paper through Google Scholar. Microworkers reached consensus or unanimous agreement for all successful searches. To answer the example question, data were aggregated and analyzed, and showed no significant association between popular opinion and attention the paper received as measured by Scimago Journal Rank and citation counts. Direct microworker costs totaled $221.75, (estimated cost at minimum wage: $312.61). We discuss important points to consider to ensure good quality control and appropriate pay for microworkers. With good reliability and low cost, crowdsourcing has potential to evaluate published literature in a cost-effective, quick, and reliable manner using existing, easily accessible resources. PMID:24988466

Brown, Andrew W.; Allison, David B.

2014-01-01

21

Approval voting and positional voting methods: Inference, relationship, examples  

Microsoft Academic Search

Approval voting is the voting method recently adopted by the Society for Social Choice and Welfare. Positional voting methods include the famous plurality, antiplurality, and Borda methods. We extend the inference framework of Tsetlin and Regenwetter (2003) from majority rule to approval voting and all positional voting methods. We also establish a link between approval voting and positional voting methods

Michel Regenwetter; Ilia Tsetlin

2004-01-01

22

Spectroscopically Enhanced Method and System for Multi-Factor Biometric Authentication  

NASA Astrophysics Data System (ADS)

This paper proposes a spectroscopic method and system for preventing spoofing of biometric authentication. One of its focus is to enhance biometrics authentication with a spectroscopic method in a multifactor manner such that a person's unique ‘spectral signatures’ or ‘spectral factors’ are recorded and compared in addition to a non-spectroscopic biometric signature to reduce the likelihood of imposter getting authenticated. By using the ‘spectral factors’ extracted from reflectance spectra of real fingers and employing cluster analysis, it shows how the authentic fingerprint image presented by a real finger can be distinguished from an authentic fingerprint image embossed on an artificial finger, or molded on a fingertip cover worn by an imposter. This paper also shows how to augment two widely used biometrics systems (fingerprint and iris recognition devices) with spectral biometrics capabilities in a practical manner and without creating much overhead or inconveniencing their users.

Pishva, Davar

23

The Erosion of a Method: Examples from Grounded Theory  

ERIC Educational Resources Information Center

Since its original inception in the 1960s grounded theory has been widely used by many qualitative researchers. However, recently epistemologically different versions of grounded theory have been presented and this epistemological diversity among grounded theorists and the erosion of the method will be the major focus of this paper. The first…

Greckhamer, Thomas; Koro-Ljungberg, Mirka

2005-01-01

24

Differences of Phosphorus in Mehlich 3 Extracts Determined by Colorimetric and Spectroscopic Methods  

Microsoft Academic Search

Mehlich 3 (M3) is a widely used extractant for evaluating plant available phosphorus (P) in soils and may be quantified using colorimetric or inductively coupled plasma (ICP) spectroscopic methods. Analysis by ICP has recently become increasingly popular in soil?testing labs primarily due to its ability to simultaneously measure multiple elements. Despite the versatility and efficiency of ICP, some laboratories hesitate

J. J. Pittman; H. Zhang; J. L. Schroder; M. E. Payton

2005-01-01

25

Review of UV spectroscopic, chromatographic, and electrophoretic methods for the cholinesterase reactivating antidote pralidoxime (2-PAM).  

PubMed

Pralidoxime (2-PAM) belongs to the class of monopyridinium oximes with reactivating potency on cholinesterases inhibited by phosphylating organophosphorus compounds (OPC), for example, pesticides and nerve agents. 2-PAM represents an established antidote for the therapy of anticholinesterase poisoning since the late 1950s. Quite high therapeutic concentrations in human plasma (about 13?µg/ml) lead to concentrations in urine being about 100 times higher allowing the use of less sensitive analytical techniques that were used especially in the early years after 2-PAM was introduced. In this time (mid-1950s until the end of the 1970s) 2-PAM was most often analyzed by either paper chromatography or simple UV spectroscopic techniques omitting any sample separation step. These methods were displaced completely after the establishment of column liquid chromatography in the early 1980s. Since then, diverse techniques including cation exchange, size-exclusion, reversed-phase, and ligand-exchange chromatography have been introduced. Today, the most popular method for 2-PAM quantification is ion pair chromatography often combined with UV detection representing more than 50% of all column chromatographic procedures published. Furthermore, electrophoretic approaches by paper and capillary zone electrophoresis have been successfully used but are seldom applied. This review provides a commentary and exhaustive summary of analytical techniques applied to detect 2-PAM in pharmaceutical formulations and biological samples to characterize stability and pharmacokinetics as well as decomposition and biotransformation products. Separation techniques as well as diverse detectors are discussed in appropriate detail allowing comparison of individual preferences and limitations. In addition, novel data on mass spectrometric fragmentation of 2-PAM are provided. PMID:21953823

John, Harald; Blum, Marc-Michael

2012-01-01

26

SPECTROSCOPIC METHODS FOR THE DETERMINATION OF SOIL CARBON  

Technology Transfer Automated Retrieval System (TEKTRAN)

Traditional methods for the determination of soil C content include chromate oxidation and combustion. Chromate oxidation generates hazardous waste and does not accurately determine all the organic soil C. Combustion methods while generating little in the way of wastes require two determinations t...

27

Structures and Encapsulation Motifs of Functional Molecules Probed by Laser Spectroscopic and Theoretical Methods  

PubMed Central

We report laser spectroscopic and computational studies of host/guest hydration interactions between functional molecules (hosts) and water (guest) in supersonic jets. The examined hosts include dibenzo-18-crown-6-ether (DB18C6), benzo-18-crown-6-ether (B18C6) and calix[4]arene (C4A). The gaseous complexes between the functional molecular hosts and water are generated under jet-cooled conditions. Various laser spectroscopic methods are applied for these species: the electronic spectra are observed by laser-induced fluorescence (LIF), mass-selected resonance enhanced multiphoton ionization (REMPI) and ultraviolet-ultraviolet hole-burning (UV-UV HB) spectroscopy, whereas the vibrational spectra for each individual species are observed by infrared-ultraviolet double resonance (IR-UV DR) spectroscopy. The obained results are analyzed by first principles electronic structure calculations. We discuss the conformations of the host molecules, the structures of the complexes, and key interactions forming the specific complexes. PMID:22319310

Kusaka, Ryoji; Inokuchi, Yoshiya; Xantheas, Sotiris S.; Ebata, Takayuki

2010-01-01

28

Application of Spectroscopic Methods for Structural Analysis of Chitin and Chitosan  

PubMed Central

Chitin, the second most important natural polymer in the world, and its N-deacetylated derivative chitosan, have been identified as versatile biopolymers for a broad range of applications in medicine, agriculture and the food industry. Two of the main reasons for this are firstly the unique chemical, physicochemical and biological properties of chitin and chitosan, and secondly the unlimited supply of raw materials for their production. These polymers exhibit widely differing physicochemical properties depending on the chitin source and the conditions of chitosan production. The presence of reactive functional groups as well as the polysaccharide nature of these biopolymers enables them to undergo diverse chemical modifications. A complete chemical and physicochemical characterization of chitin, chitosan and their derivatives is not possible without using spectroscopic techniques. This review focuses on the application of spectroscopic methods for the structural analysis of these compounds. PMID:20559489

Kumirska, Jolanta; Czerwicka, Ma?gorzata; Kaczy?ski, Zbigniew; Bychowska, Anna; Brzozowski, Krzysztof; Thöming, Jorg; Stepnowski, Piotr

2010-01-01

29

Investigation on the interaction of pyrene with bovine serum albumin using spectroscopic methods  

NASA Astrophysics Data System (ADS)

This paper was designed to investigate the interaction of pyrene with bovine serum albumin (BSA) under physiological condition by spectroscopic methods. Spectroscopic analysis of the emission quenching revealed that the quenching mechanism of BSA by pyrene was static. The binding sites and constants of pyrene-BSA complex were observed to be 1.20 and 2.63 × 106 L mol-1 at 298 K, respectively. The enthalpy change (?H) and entropy change (?S) revealed that van der Waals forces and hydrogen bonds stabilized the pyrene-BSA complex. Energy transfer from tryptophan to pyrene occurred by a FRET (fluorescence resonance energy transfer) mechanism, and the distance (r = 2.72 nm) had been determined. The results of synchronous, three-dimensional fluorescence, and circular dichroism spectra showed that the pyrene induced conformational changes of BSA.

Xu, Chengbin; Gu, Jiali; Ma, Xiping; Dong, Tian; Meng, Xuelian

30

Interaction of methotrexate with trypsin analyzed by spectroscopic and molecular modeling methods  

NASA Astrophysics Data System (ADS)

Trypsin is one of important digestive enzymes that have intimate correlation with human health and illness. In this work, the interaction of trypsin with methotrexate was investigated by spectroscopic and molecular modeling methods. The results revealed that methotrexate could interact with trypsin with about one binding site. Methotrexate molecule could enter into the primary substrate-binding pocket, resulting in inhibition of trypsin activity. Furthermore, the thermodynamic analysis implied that electrostatic force, hydrogen bonding, van der Waals and hydrophobic interactions were the main interactions for stabilizing the trypsin-methotrexate system, which agreed well with the results from the molecular modeling study.

Wang, Yanqing; Zhang, Hongmei; Cao, Jian; Zhou, Qiuhua

2013-11-01

31

Plant architecture comparison methods: A review of existing algorithms and examples of application  

E-print Network

Plant architecture comparison methods: A review of existing algorithms and examples of application, France {segura|costes}@supagro.inra.fr Keywords: Plant comparison, edit distances, local similarities, analyze, model and visualize plant architecture in 3-dimensions, this paper focuses on methods dedicated

Paris-Sud XI, Université de

32

SIMPLE EXAMPLES OF THE COMBINATORIAL TRACE METHOD IN MIKE KREBS AND NATALIE C. MARTINEZ  

E-print Network

Fibonacci and Lucas numbers. Applying this method to other small graphs, one can easily generate interesting: November 28, 2011. Key words and phrases. Lucas numbers, Fibonacci numbers, adjacency matrix, finite graph. 1. Simple examples of the method in action: Binet formulae for Fibonacci and Lucas nunbers We start

Krebs, Mike

33

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone  

E-print Network

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone and propagation of tropical cyclone Erica. Sensitiv- ity tests to the coupling method are carried out-way coupling is essential for analyzing energetic and complex phenomena like tropical cyclones (e.g. Bao et al

34

Spectroscopic characterization and quantitative determination of atorvastatin calcium impurities by novel HPLC method  

NASA Astrophysics Data System (ADS)

Seven process related impurities were identified by LC-MS in the atorvastatin calcium drug substance. These impurities were identified by LC-MS. The structure of impurities was confirmed by modern spectroscopic techniques like 1H NMR and IR and physicochemical studies conducted by using synthesized authentic reference compounds. The synthesized reference samples of the impurity compounds were used for the quantitative HPLC determination. These impurities were detected by newly developed gradient, reverse phase high performance liquid chromatographic (HPLC) method. The system suitability of HPLC analysis established the validity of the separation. The analytical method was validated according to International Conference of Harmonization (ICH) with respect to specificity, precision, accuracy, linearity, robustness and stability of analytical solutions to demonstrate the power of newly developed HPLC method.

Gupta, Lokesh Kumar

2012-11-01

35

Detailed spectroscopic analysis of SN 1987A: The distance to the LMC using the SEAM method  

SciTech Connect

Supernova 1987A remains the most well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model the observed spectra from Day 1 to Day 81 using a hydrodynamical model. We show that good agreement can be obtained at times up to about 60 days, if we allow for extended nickel mixing. Later than about 60 days the observed Balmer lines become stronger than our models can reproduce. We show that this is likely due to a more complicated distribution of gamma-rays than we allow for in our spherically symmetric calculations. We present synthetic light curves in UBVRIJHK and a synthetic bolometric light curve. Using this broad baseline of detailed spectroscopic models we find a distance modulus mu = 18.5 +/- 0.2 using the SEAM method of determining distances to supernovae. We find that the explosion time agrees with that of the neutrino burst and is constrained at 68 percent confidence to within +/- 0.9 days. We argue that the weak Balmer lines of our detailed model calculations casts doubt on the accuracy of the purely photometric EPM method. We also suggest that Type IIP supernovae will be most useful as distance indicators at early times due to a variety of effects.

Mitchell, Robert C.; Baron, E.; Branch, David; Hauschildt, Peter H.; Nugent, Peter E.; Lundqvist, Peter; Blinnikov, Sergei; Pun, Chun S.J.

2002-05-21

36

Novel spectroscopic methods for determination of Cromolyn sodium and Oxymetazoline hydrochloride in binary mixture  

NASA Astrophysics Data System (ADS)

New accurate, sensitive and selective spectrophotometric and spectrofluorimetric methods were developed and subsequently validated for determination of Cromolyn sodium (CS) and Oxymetazoline HCl (OXY) in binary mixture. These methods include ‘H-point standard addition method (HPSAM) and area under the curve (AUC)' spectrophotometric method and first derivative synchronous fluorescence spectroscopic (FDSFS) method. For spectrophotometric methods, absorbances were recorded at 241.5 nm and 274.9 nm for HPSAM and the wavelength was selected in ranges 232.0-254.0 nm and 216.0-229.0 nm for AUC method, where the concentration was obtained by applying Cramer's rule. For FDSFS method, the first-derivative synchronous fluorescence signal was measured at 290.0 nm, using ?? = 145.0 nm. The suggested methods were validated according to International Conference of Harmonization (ICH) guidelines and the results revealed that they were precise and reproducible. All the obtained results were statistically compared with those of the reported method and there was no significant difference.

Abdel-Aziz, Omar; El-Kosasy, A. M.; Magdy, N.; El Zahar, N. M.

2014-10-01

37

Novel spectroscopic methods for determination of Cromolyn sodium and Oxymetazoline hydrochloride in binary mixture.  

PubMed

New accurate, sensitive and selective spectrophotometric and spectrofluorimetric methods were developed and subsequently validated for determination of Cromolyn sodium (CS) and Oxymetazoline HCl (OXY) in binary mixture. These methods include 'H-point standard addition method (HPSAM) and area under the curve (AUC)' spectrophotometric method and first derivative synchronous fluorescence spectroscopic (FDSFS) method. For spectrophotometric methods, absorbances were recorded at 241.5nm and 274.9nm for HPSAM and the wavelength was selected in ranges 232.0-254.0nm and 216.0-229.0nm for AUC method, where the concentration was obtained by applying Cramer's rule. For FDSFS method, the first-derivative synchronous fluorescence signal was measured at 290.0nm, using ??=145.0nm. The suggested methods were validated according to International Conference of Harmonization (ICH) guidelines and the results revealed that they were precise and reproducible. All the obtained results were statistically compared with those of the reported method and there was no significant difference. PMID:24820323

Abdel-Aziz, Omar; El-Kosasy, A M; Magdy, N; El Zahar, N M

2014-10-15

38

Spectroscopic networks  

NASA Astrophysics Data System (ADS)

Approaches related to graph theory are given which allow a better understanding of and yield routes for systematic enlargement and improvement of experimental spectroscopic line lists of molecules. The protocols are based on the fact that the information in line lists can be related to large-scale, weighted, undirected graphs, whereby the vertices are discrete energy levels, the edges are transitions, and the weights are transition intensities. The resulting graph is what one may call a spectroscopic network (SN). It is shown on the example of the HD16O isotopologue of the water molecule that both its measured and first-principles one-photon absorption SNs have a scale-free behavior with all of the usual consequences, including appearance of hubs, robustness, error tolerance, and the "small-world" property. The graph-theoretical view of molecular spectra offers several new ideas for improving the accuracy and robustness of the information systems containing high-resolution spectroscopic data.

Csaszar, A. G.; Furtenbacher, T.

2011-05-01

39

Laser apparatus and method for microscopic and spectroscopic analysis and processing of biological cells  

DOEpatents

An apparatus and method are disclosed for microscopic and spectroscopic analysis and processing of biological cells. The apparatus comprises a laser having an analysis region within the laser cavity for containing one or more biological cells to be analyzed. The presence of a cell within the analysis region in superposition with an activated portion of a gain medium of the laser acts to encode information about the cell upon the laser beam, the cell information being recoverable by an analysis means that preferably includes an array photodetector such as a CCD camera and a spectrometer. The apparatus and method may be used to analyze biomedical cells including blood cells and the like, and may include processing means for manipulating, sorting, or eradicating cells after analysis. 20 figs.

Gourley, P.L.; Gourley, M.F.

1997-03-04

40

Laser apparatus and method for microscopic and spectroscopic analysis and processing of biological cells  

DOEpatents

An apparatus and method for microscopic and spectroscopic analysis and processing of biological cells. The apparatus comprises a laser having an analysis region within the laser cavity for containing one or more biological cells to be analyzed. The presence of a cell within the analysis region in superposition with an activated portion of a gain medium of the laser acts to encode information about the cell upon the laser beam, the cell information being recoverable by an analysis means that preferably includes an array photodetector such as a CCD camera and a spectrometer. The apparatus and method may be used to analyze biomedical cells including blood cells and the like, and may include processing means for manipulating, sorting, or eradicating cells after analysis thereof.

Gourley, Paul L. (12508 Loyola, NE., Albuquerque, NM 87112); Gourley, Mark F. (7509 Spring Lake Dr., Apt. B1, Bethesda, MD 20817)

1997-01-01

41

Spectroscopic and molecular structure investigations of 9-vinylcarbazole by DFT and ab initio method  

NASA Astrophysics Data System (ADS)

Fourier transform infrared (FT-IR) and FT-Raman spectra have been recorded and widespread spectroscopic investigations have been carried out on 9-vinylcarbazole (9VC). The optimized geometries, vibrational wavenumbers, intensity of vibrational bands and various atomic charges of 9VC have been investigated using Hartree-Fock (HF) and density functional theory (DFT-B3LYP) method using 6-31G(d,p) as basis set. Experimental fundamental vibrational modes are scrutinized and compared with the calculated results. 13C and 1H NMR spectra were recorded and the chemical shifts of the molecule have been computed using GIAO method. The nonlinear property of the title compound was confirmed by hyperpolarizability. Molecular stability and bond strength was analyzed by Natural Bond Orbital analysis. Electronic structure properties such as UV and frontier molecular orbital examination have been reported.

Jone Pradeepa, S.; Sundaraganesan, N.

2015-02-01

42

Spectroscopic and molecular structure investigations of 9-vinylcarbazole by DFT and ab initio method.  

PubMed

Fourier transform infrared (FT-IR) and FT-Raman spectra have been recorded and widespread spectroscopic investigations have been carried out on 9-vinylcarbazole (9VC). The optimized geometries, vibrational wavenumbers, intensity of vibrational bands and various atomic charges of 9VC have been investigated using Hartree-Fock (HF) and density functional theory (DFT-B3LYP) method using 6-31G(d,p) as basis set. Experimental fundamental vibrational modes are scrutinized and compared with the calculated results. (13)C and (1)H NMR spectra were recorded and the chemical shifts of the molecule have been computed using GIAO method. The nonlinear property of the title compound was confirmed by hyperpolarizability. Molecular stability and bond strength was analyzed by Natural Bond Orbital analysis. Electronic structure properties such as UV and frontier molecular orbital examination have been reported. PMID:25448968

Jone Pradeepa, S; Sundaraganesan, N

2015-02-01

43

Data processing method applying principal component analysis and spectral angle mapper for imaging spectroscopic sensors  

NASA Astrophysics Data System (ADS)

A data processing method for hyperspectral images is presented. Each image contains the whole diffuse reflectance spectra of the analyzed material for all the spatial positions along a specific line of vision. This data processing method is composed of two blocks: data compression and classification unit. Data compression is performed by means of Principal Component Analysis (PCA) and the spectral interpretation algorithm for classification is the Spectral Angle Mapper (SAM). This strategy of classification applying PCA and SAM has been successfully tested on the raw material on-line characterization in the tobacco industry. In this application case the desired raw material (tobacco leaves) should be discriminated from other unwanted spurious materials, such as plastic, cardboard, leather, candy paper, etc. Hyperspectral images are recorded by a spectroscopic sensor consisting of a monochromatic camera and a passive Prism- Grating-Prism device. Performance results are compared with a spectral interpretation algorithm based on Artificial Neural Networks (ANN).

García-Allende, P. B.; Conde, O. M.; Mirapeix, J.; Cubillas, A. M.; López-Higuera, J. M.

2007-07-01

44

Structures and Encapsulation Motifs of Functional Molecules probed by Laser Spectroscopic and Theoretical methods  

SciTech Connect

We report laser spectroscopic studies of host/guest hydration interactions between functional molecules (hosts) and water (guest) in supersonic jets. The examined hosts include dibenzo-18-crown-6-ether (DB18C6), benzo-18-crown-6-ether (B18C6) and calix[4]arene (C4A). The gaseous complexes between the functional molecular hosts and water are generated under jet-cooled conditions. Various laser spectroscopic methods are applied for these species: the electronic spectra are observed by laser-induced fluorescence (LIF) , massselected resonance enhanced multiphoton ionization (REMPI) and ultraviolet-ultraviolet holeburning (UV-UV HB) spectroscopy, whereas the vibrational spectra for each individual species are observed by infrared-ultraviolet double resonance (IR-UV DR) spectroscopy. The obained results are analyzed by first principles electronic structure calculations. We discuss the conformations of the host molecules, the various structures of the complexes and the key interactions that result in the complexation as well as the effect of the host conformation in the resulting complexation mechanism.

Kusaka, Ryoji; Inokuchi, Yoshiya; Xantheas, Sotiris S.; Ebata, Takayuki

2010-04-01

45

Some illustrative examples of the use of a spectral-element method in ocean acoustics  

E-print Network

Express Letters [DOI: 10.1121/1.3682459] Published Online 16 February 2012 #12;examples including a movie the wide variety of media that can be considered within the framework of this method. Finally, a movie, respectively, named SPECFEM2D and SPECFEM3D, are available for free on the Computational Initiative

Komatitsch, Dimitri

46

Models of near-field spectroscopic studies: comparison between Finite-Element and Finite-Difference methods  

Microsoft Academic Search

We compare the numerical results obtained by the Finite Element Method (FEM) and the Finite Difference Time Domain Method (FDTD) for near-field spectroscopic studies and intensity map computations. We evaluate their respective efficiencies and we show that an accurate description of the dispersion and of the geometry of the material must be included for a realistic modeling. In particular for

Thomas Grosges; Alexandre Vial; Dominique Barchiesi

2005-01-01

47

Apparatus for and method of performing spectroscopic analysis on an article  

DOEpatents

An apparatus and method are disclosed for analyzing an article having an entrance and an exit in communication with the entrance. The apparatus comprises: a spectrometer having an emission source with a focal point; a plurality of mirrors; and a detector connected to the spectroscope. The emission source is positioned so that its focal point is substantially coextensive with the entrance of the article. The mirrors comprise: a first mirror positionable adjacent the exit of the article and a second mirror positioned relative to the other of said plurality of mirrors. The first mirror receives scattered emissions exiting the article and substantially collimates the scattered emissions. The second mirror substantially focuses the collimated emissions into a focused emission. The detector receives the focused emission from the mirrors. 6 figs.

Powell, G.L.; Hallman, R.L. Jr.

1999-04-20

48

Apparatus for and method of performing spectroscopic analysis on an article  

DOEpatents

An apparatus for and method of analyzing an article having an entrance and an exit in communication with the entrance. The apparatus comprises: a spectrometer having an emission source with a focal point; a plurality of mirrors; and a detector connected to the spectroscope. The emission source is positioned so that its focal point is substantially coextensive with the entrance of the article. The mirrors comprise: a first mirror positionable adjacent the exit of the article and a second mirror positioned relative to the other of said plurality of mirrors. The first mirror receives scattered emissions exiting the article and substantially collimates the scattered emissions. The second mirror substantially focuses the collimated emissions into a focused emission. The detector receives the focused emission from the mirrors.

Powell, George Louis (Oak Ridge, TN); Hallman, Jr., Russell Louis (Knoxville, TN)

1999-01-01

49

Automatic diagnosis of melanoma using machine learning methods on a spectroscopic system  

PubMed Central

Background Early and accurate diagnosis of melanoma, the deadliest type of skin cancer, has the potential to reduce morbidity and mortality rate. However, early diagnosis of melanoma is not trivial even for experienced dermatologists, as it needs sampling and laboratory tests which can be extremely complex and subjective. The accuracy of clinical diagnosis of melanoma is also an issue especially in distinguishing between melanoma and mole. To solve these problems, this paper presents an approach that makes non-subjective judgements based on quantitative measures for automatic diagnosis of melanoma. Methods Our approach involves image acquisition, image processing, feature extraction, and classification. 187 images (19 malignant melanoma and 168 benign lesions) were collected in a clinic by a spectroscopic device that combines single-scattered, polarized light spectroscopy with multiple-scattered, un-polarized light spectroscopy. After noise reduction and image normalization, features were extracted based on statistical measurements (i.e. mean, standard deviation, mean absolute deviation, L 1 norm, and L 2 norm) of image pixel intensities to characterize the pattern of melanoma. Finally, these features were fed into certain classifiers to train learning models for classification. Results We adopted three classifiers – artificial neural network, naïve bayes, and k-nearest neighbour to evaluate our approach separately. The naive bayes classifier achieved the best performance - 89% accuracy, 89% sensitivity and 89% specificity, which was integrated with our approach in a desktop application running on the spectroscopic system for diagnosis of melanoma. Conclusions Our work has two strengths. (1) We have used single scattered polarized light spectroscopy and multiple scattered unpolarized light spectroscopy to decipher the multilayered characteristics of human skin. (2) Our approach does not need image segmentation, as we directly probe tiny spots in the lesion skin and the image scans do not involve background skin. The desktop application for automatic diagnosis of melanoma can help dermatologists get a non-subjective second opinion for their diagnosis decision. PMID:25311811

2014-01-01

50

Spectroscopic networks  

NASA Astrophysics Data System (ADS)

Approaches related to graph theory are investigated which allow a better understanding and yield routes for systematic enlargement and improvement of experimental spectroscopic line lists of molecules. The proposed protocols are based on the fact that quantum mechanics builds, in a simple and natural way, large-scale, weighted, undirected graphs, whereby the vertices are discrete energy levels, the edges are transitions, and the weights are transition intensities. A small part of molecular quantum mechanical graphs can be probed experimentally via high-resolution spectroscopic techniques, while the complete graph encompassing the full line list information for a given molecule can be obtained through sophisticated variational nuclear motion computations. Both approaches yield what one may call spectroscopic networks (SNs). It is shown on the example of the HD 16O isotopologue of the water molecule that both the measured and the computed one-photon absorption SNs have a scale-free behavior with all of the usual consequences, including appearance of hubs, robustness, error tolerance, and the "small-world" property. For the complete computed "deterministic" network the scale-free property holds if a realistic intensity cut-off is employed during its build-up, thus introducing "stochasticity". The graph-theoretical view of molecular spectra offers several new ideas for improving the accuracy and robustness of the information systems containing high-resolution spectroscopic data.

Császár, Attila G.; Furtenbacher, Tibor

2011-04-01

51

Near-infrared spectroscopic method for real-time monitoring of pharmaceutical powders during voiding.  

PubMed

A near-infrared (NIR) spectroscopic method has been developed to monitor flowing pharmaceutical powders during their voiding and detect post-blending segregation. The method is capable of providing both chemical and physical information (particle size differences) on the flowing pharmaceutical powders. Particle size differences are widely recognized as the predominant driver for segregation. Pharmaceutical powders may segregate following blending as they are voided down pipes to compressing machines, increasing the variability of the drug content and dissolution of the final product tablets because of segregation. NIR diffuse reflectance spectra of pharmaceutical powders were obtained following voiding through a six-foot pipe. Spectral subtraction was used to eliminate baseline differences but maintain particle size differences. The NIR spectra indicated differences in the particle size of the flowing powder. Particle size differences were also tracked throughout the voiding of pharmaceutical powders by plotting the absorbance at 1536 nm. The method was also applied to the voiding of two layers of lactose particles with different particle sizes. The system described in this report provides an approach to study post-blending segregation in pharmaceutical powders and other relevant materials. PMID:17555618

Barajas, Martha J; Cassiani, Alex Rodriguez; Vargas, Wandylis; Conde, Carlos; Ropero, Jorge; Figueroa, Jorge; Romañach, Rodolfo J

2007-05-01

52

Pedagogies in Action: A Community Resource Linking Teaching Methods to Examples of their Use  

NASA Astrophysics Data System (ADS)

The Pedagogies in Action portal (http://serc.carleton.edu/sp) provides access to information on more than 40 teaching methods with examples of their use in geoscience and beyond. Each method is described with pages addressing what the method is, why or when it is useful, and how it can be implemented. New methods added this year include Teaching with Google Earth, Jigsaw, Teaching the Process of Science, Guided Discovery Problems, Teaching Urban Students, and Using ConceptTests. Examples then show specifically how the method has been used to teach concepts in a variety of disciplines. The example collection now includes 775 teaching activities of which more than 550 are drawn from the geosciences. Geoscience faculty are invited to add their own examples to this collection or to test examples in the collection and provide a review. Evaluation results show that the combination of modules and activities inspires teachers at all levels to use a new pedagogy and increases their confidence that they can use it successfully. In addition, submitting activities to the collection, including writing summary information for other instructors, helps them think more carefully about the design of their activity. The activity collections are used both for ready to use activities and to find ideas for new activities. The portal provides overarching access to materials developed by a wide variety of collaborating partners each of which uses the service to create a customized pedagogic portal addressing a more specific audience. Of interest to AGU members are pedagogic portals on Starting Point: Teaching Introductory Geoscience (http://serc.carleton.edu/introgeo); On the Cutting Edge (http://serc.carleton.edu/NAGTWorkshops); Enduring Resources for Earth System Education (http://earthref.org/ERESE) Microbial Life Educational Resources (http://serc.carleton.edu/microbe_life); the National Numeracy Network (http://serc.carleton.edu/nnn/index.html); CAUSE: The Consortium for Undergraduate Statistics Education (http://causeweb.org); ComPADRE: Digital Resources for Physics and Astronomy Education (http://www.compadre.org) and Project Kaleidoscope (http://pkal.org). Pedagogies in Action is part of the National Science Digital Library (http://nsdl.org). Projects or groups interested in exploring use of the service can find information about using the service on the project website or contact the authors.

Manduca, C. A.; Fox, S. P.; Iverson, E. A.; Kirk, K.; Ormand, C. J.

2009-12-01

53

A Review of Computational Methods in Materials Science: Examples from Shock-Wave and Polymer Physics  

PubMed Central

This review discusses several computational methods used on different length and time scales for the simulation of material behavior. First, the importance of physical modeling and its relation to computer simulation on multiscales is discussed. Then, computational methods used on different scales are shortly reviewed, before we focus on the molecular dynamics (MD) method. Here we survey in a tutorial-like fashion some key issues including several MD optimization techniques. Thereafter, computational examples for the capabilities of numerical simulations in materials research are discussed. We focus on recent results of shock wave simulations of a solid which are based on two different modeling approaches and we discuss their respective assets and drawbacks with a view to their application on multiscales. Then, the prospects of computer simulations on the molecular length scale using coarse-grained MD methods are covered by means of examples pertaining to complex topological polymer structures including star-polymers, biomacromolecules such as polyelectrolytes and polymers with intrinsic stiffness. This review ends by highlighting new emerging interdisciplinary applications of computational methods in the field of medical engineering where the application of concepts of polymer physics and of shock waves to biological systems holds a lot of promise for improving medical applications such as extracorporeal shock wave lithotripsy or tumor treatment. PMID:20054467

Steinhauser, Martin O.; Hiermaier, Stefan

2009-01-01

54

Determination of Cephalexin Monohydrate in Pharmaceutical Dosage Form by Stability-Indicating RP-UFLC and UV Spectroscopic Methods  

PubMed Central

An ultra-fast liquid chromatographic method and two UV spectroscopic methods were developed for the determination of cephalexin monohydrate in pharmaceutical dosage forms. Isocratic separation was performed on an Enable C18G column (250 mm × 4.6 mm i.d., 5 ?m) using methanol:0.01 M TBAHS (50:50, v/v) as the mobile phase at a flow rate of 1.0 ml/min. The PDA detection wavelength was set at 254 nm. The UV spectroscopic method was performed at 261 nm and at 256–266 nm for the AUC method using a phosphate buffer (pH=5.5). The linearity was observed over a concentration range of 1.0–120 ?g/ml for UFLC and both of the UV spectroscopic methods (correlation coefficient=0.999). The developed methods were validated according to ICH guidelines. The relative standard deviation values for the intraday and interday precision studies were < 2%, and the accuracy was > 99% for all of the three methods. The developed methods were used successfully for the determination of cephalexin in dry syrup formulation. PMID:24482771

Panda, Sagar Suman; Ravi Kumar, Bera V. V.; Dash, Rabisankar; Mohanta, Ganeswar

2013-01-01

55

Comparability of a Three-Dimensional Structure in Biopharmaceuticals Using Spectroscopic Methods  

PubMed Central

Protein structure depends on weak interactions and covalent bonds, like disulfide bridges, established according to the environmental conditions. Here, we present the validation of two spectroscopic methodologies for the measurement of free and unoxidized thiols, as an attribute of structural integrity, using 5,5?-dithionitrobenzoic acid (DTNB) and DyLight Maleimide (DLM) as derivatizing agents. These methods were used to compare Rituximab and Etanercept products from different manufacturers. Physicochemical comparability was demonstrated for Rituximab products as DTNB showed no statistical differences under native, denaturing, and denaturing-reducing conditions, with Student's t-test P values of 0.6233, 0.4022, and 0.1475, respectively. While for Etanercept products no statistical differences were observed under native (P = 0.0758) and denaturing conditions (P = 0.2450), denaturing-reducing conditions revealed cysteine contents of 98% and 101%, towards the theoretical value of 58, for the evaluated products from different Etanercept manufacturers. DLM supported equality between Rituximab products under native (P = 0.7499) and denaturing conditions (P = 0.8027), but showed statistical differences among Etanercept products under native conditions (P < 0.001). DLM suggested that Infinitam has fewer exposed thiols than Enbrel, although DTNB method, circular dichroism (CD), fluorescence (TCSPC), and activity (TNF? neutralization) showed no differences. Overall, this data revealed the capabilities and drawbacks of each thiol quantification technique and their correlation with protein structure. PMID:24963443

Abad-Javier, Mario E.; Romero-Díaz, Alexis J.; Villaseñor-Ortega, Francisco; Pérez, Néstor O.; Flores-Ortiz, Luis F.

2014-01-01

56

Comment on “Quantitative comparison of analysis methods for spectroscopic optical coherence tomography”  

PubMed Central

In a recent paper by Bosschaart et al. [Biomed. Opt. Express 4, 2570 (2013)] various algorithms of time-frequency signal analysis have been tested for their performance in blood analysis with spectroscopic optical coherence tomography (sOCT). The measurement of hemoglobin concentration and oxygen saturation based on blood absorption spectra have been considered. Short time Fourier transform (STFT) was found as the best method for the measurement of blood absorption spectra. STFT was superior to other methods, such as dual window Fourier transform. However, the algorithm proposed by Bosschaart et al. significantly underestimates values of blood oxygen saturation. In this comment we show that this problem can be solved by thorough design of STFT algorithm. It requires the usage of a non-gaussian shape of STFT window that may lead to an excellent reconstruction of blood absorption spectra from OCT interferograms. Our study shows that sOCT can be potentially used for estimating oxygen saturation of blood with the accuracy below 1% and the spatial resolution of OCT image better than 20 ?m. PMID:25401015

Kraszewski, Maciej; Trojanowski, Micha?; Str?kowski, Marcin R.

2014-01-01

57

Spectroscopic database  

NASA Technical Reports Server (NTRS)

Several aspects of quantitative atmospheric spectroscopy are considered, using a classification of the molecules according to the gas amounts in the stratosphere and upper troposphere, and reviews of quantitative atmospheric high-resolution spectroscopic measurements and field measurements systems are given. Laboratory spectroscopy and spectral analysis and prediction are presented with a summary of current laboratory spectroscopy capabilities. Spectroscopic data requirements for accurate derivation of atmospheric composition are discussed, where examples are given for space-based remote sensing experiments of the atmosphere: the ATMOS (Atmospheric Trace Molecule) and UARS (Upper Atmosphere Research Satellite) experiment. A review of the basic parameters involved in the data compilations; a summary of information on line parameter compilations already in existence; and a summary of current laboratory spectroscopy studies are used to assess the data base.

Husson, N.; Barbe, A.; Brown, L. R.; Carli, B.; Goldman, A.; Pickett, H. M.; Roche, A. E.; Rothman, L. S.; Smith, M. A. H.

1985-01-01

58

Fluorescent-spectroscopic and imaging methods of investigations for diagnostics of head and neck tumors and control of PDT  

NASA Astrophysics Data System (ADS)

Methodics of PDT control and fluorescent-spectroscopic diagnostic of head and neck tumors and mammary gland cancer (nodular) with the use of Kr, He-Ne and semiconductor lasers and photosensitizer (PS) -- Al phtalocyanin (Photosense) are discussed. The results show that applied diagnostic methods permit us not only to identify the topology and malignancy of a tumor but also to correct PDT process directly during irradiation.

Edinak, N. E.; Chental, Victor V.; Komov, D.; Vaculovskaya, E.; Tabolinovskaya, T. D.; Abdullin, N. A.; Pustynsky, I.; Chatikhin, V.; Loschenov, Victor B.; Meerovich, Gennady A.; Stratonnikov, A. A.; Linkov, Kirill G.; Agafonov, Vladimir I.; Zuravleva, V.; Lukjanets, E.

1996-01-01

59

Dissection of the binding of hydrogen peroxide to trypsin using spectroscopic methods and molecular modeling  

NASA Astrophysics Data System (ADS)

Studies on the effects of environmental pollutants to protein in vitro has become a global attention. Hydrogen peroxide (H2O2) is used as an effective food preservative and bleacher in industrial production. The toxicity of H2O2 to trypsin was investigated by multiple spectroscopic techniques and the molecular docking method at the molecular level. The intrinsic fluorescence of trypsin was proved to be quenched in a static process based on the results of fluorescence lifetime experiment. Hydrogen bonds interaction and van der Waals forces were the main force to generate the trypsin-H2O2 complex on account of the negative ?H0 and ?S0. The binding of H2O2 changed the conformational structures and internal microenvironment of trypsin illustrated by UV-vis absorption, fluorescence, synchronous fluorescence, three-dimensional (3D) fluorescence and circular dichroism (CD) results. However, the binding site was far away from the active site of trypsin and the trypsin activity was only slightly affected by H2O2, which was further explained by molecular docking investigations.

Song, Wei; Yu, Zehua; Hu, Xinxin; Liu, Rutao

2015-02-01

60

Probing HSA-ionic liquid interactions by spectroscopic and molecular docking methods.  

PubMed

Herein, we report the interaction of synthesized pyrrolidinium based ionic liquid, N-butyl-N-methyl-2-oxopyrrolidinium bromide (BMOP) with human serum albumin (HSA). The BMOP was characterized by using (1)H NMR, (13)C NMR and FT-IR techniques. The critical micelle concentration (cmc) of BMOP was confirmed by surface tension, conductivity and contact angle measurements. The interactions between HSA and BMOP were studied by steady-state and time-resolved fluorescence, UV-visible, FT-IR spectroscopic and molecular docking methods. The steady-state fluorescence spectra showed that BMOP quenched the fluorescence of HSA through combined quenching mechanism. Corresponding thermodynamic parameters viz. Gibbs free energy change (?G), entropy change (?S) and enthalpy change (?H) illustrated that the binding process was spontaneous and entropy driven. It is also suggested that hydrophobic forces play a key role in the binding of BMOP to HSA. In addition, the pyrene probe analysis again suggests the involvement of hydrophobic interaction in HSA-BMOP complex formation. Surface tension profile showed that the cmc value of BMOP in the presence of HSA is higher than the cmc value of pure BMOP. The FT-IR results show a conformational change in the secondary structure of HSA upon the addition of BMOP. The molecular docking result indicated that BMOP binds with HSA at hydrophobic pocket domain IIA with hydrophobic and hydrogen bond interactions in which hydrophobic interactions are dominating. PMID:24911269

Kumari, Meena; Maurya, Jitendra Kumar; Tasleem, Munazzah; Singh, Prashant; Patel, Rajan

2014-09-01

61

Analysis of interaction between tamoxifen and ctDNA in vitro by multi-spectroscopic methods  

NASA Astrophysics Data System (ADS)

Multi-spectroscopic methods including resonance light scattering (RLS), ultraviolet spectra (UV), fluorescence spectra, 1H NMR spectroscopy, coupled with thermo-denaturation experiments were firstly used to study the interaction of antitumor drug tamoxifen (TMX) with calf thymus (ctDNA) in acetate buffer solutions (pH 4.55). The interaction of TMX with ctDNA could cause a significant enhancement of RLS intensity, the hyperchromic effect, red shift of absorption spectra and the fluorescence quenching of TMX, indicating that there is an inserting interaction between TMX and ctDNA. This inference was confirmed by 1H NMR spectroscopy. The chemical shift of the benzene proton changes significantly which indicates that TMX could insert into the base pairs of ctDNA. These studies are valuable for a better understanding the mode of TMX-ctDNA interaction further, which are important and useful for designing of new ctDNA targeted drug. And the antitumor drug TMX inserted directly into ctDNA in vitro, which can provide a lot of useful information to explore the development of new and highly effective anti-cancer drugs.

Cai, Changqun; Chen, Xiaoming; Ge, Fei

2010-07-01

62

The interaction of plant-growth regulators with serum albumin: molecular modeling and spectroscopic methods.  

PubMed

The affinity between two plant-growth regulators (PGRs) and human serum albumin (HSA) was investigated by molecular modeling techniques and spectroscopic methods. The results of molecular modeling simulations revealed that paclobutrazol (PAC) could bind on both site I and site II in HSA where the interaction was easier, while uniconazole (UNI) could not bind with HSA. Furthermore, the results of fluorescence spectroscopy, three-dimensional (3D) fluorescence spectroscopy and circular dichroism (CD) spectroscopy suggested that PAC had a strong ability to quench the intrinsic fluorescence of HSA. The binding affinity (Kb) and the amounts of binding sites (n) between PAC and HSA at 291 K were estimated as 2.37×10(5) mol L(-1) and 1, respectively, which confirm that PAC mainly binds on site II of HSA. An apparent distance between the Trp214 and PAC was 4.41 nm. Additionally, the binding of PAC induced the conformational changes of disulfide bridges of HSA with the decrease of ?-helix content. These studies provide more information on the potential toxicological effects and environmental risk assessment of PGRs. PMID:24569069

Dong, Sheying; Li, Zhiqin; Shi, Ling; Huang, Guiqi; Chen, Shuangli; Huang, Tinglin

2014-05-01

63

Dissection of the binding of hydrogen peroxide to trypsin using spectroscopic methods and molecular modeling.  

PubMed

Studies on the effects of environmental pollutants to protein in vitro has become a global attention. Hydrogen peroxide (H2O2) is used as an effective food preservative and bleacher in industrial production. The toxicity of H2O2 to trypsin was investigated by multiple spectroscopic techniques and the molecular docking method at the molecular level. The intrinsic fluorescence of trypsin was proved to be quenched in a static process based on the results of fluorescence lifetime experiment. Hydrogen bonds interaction and van der Waals forces were the main force to generate the trypsin-H2O2 complex on account of the negative ?H(0) and ?S(0). The binding of H2O2 changed the conformational structures and internal microenvironment of trypsin illustrated by UV-vis absorption, fluorescence, synchronous fluorescence, three-dimensional (3D) fluorescence and circular dichroism (CD) results. However, the binding site was far away from the active site of trypsin and the trypsin activity was only slightly affected by H2O2, which was further explained by molecular docking investigations. PMID:25228036

Song, Wei; Yu, Zehua; Hu, Xinxin; Liu, Rutao

2015-02-25

64

Integrating informative priors from experimental research with Bayesian methods: an example from radiation epidemiology.  

PubMed

Informative priors can be a useful tool for epidemiologists to handle problems of sparse data in regression modeling. It is sometimes the case that an investigator is studying a population exposed to two agents, X and Y, where Y is the agent of primary interest. Previous research may suggest that the exposures have different effects on the health outcome of interest, one being more harmful than the other. Such information may be derived from epidemiologic analyses; however, in the case where such evidence is unavailable, knowledge can be drawn from toxicologic studies or other experimental research. Unfortunately, using toxicologic findings to develop informative priors in epidemiologic analyses requires strong assumptions, with no established method for its utilization. We present a method to help bridge the gap between animal and cellular studies and epidemiologic research by specification of an order-constrained prior. We illustrate this approach using an example from radiation epidemiology. PMID:23222512

Hamra, Ghassan; Richardson, David; Maclehose, Richard; Wing, Steve

2013-01-01

65

Characterization of Mannitol Polymorphic Forms in Lyophilized Protein Formulations Using a Multivariate Curve Resolution (MCR)Based Raman Spectroscopic Method  

Microsoft Academic Search

Purpose  To develop a novel multivariate curve resolution (MCR)-based Raman spectroscopic method to characterize and quantify five\\u000a known mannitol solid-state forms in lyophilized protein formulations.\\u000a \\u000a \\u000a \\u000a Materials and Methods  The multivariate quantitation method was developed based on second derivative Raman spectra of three anhydrous crystalline\\u000a forms (?-, ?-, and ?-mannitol), a hemihydrate and an amorphous mannitol form. The method showed a 5% quantitation

Yong Xie; Wenjin Cao; Sampathkumar Krishnan; Hong Lin; Nina Cauchon

2008-01-01

66

Infrared study of aging of edible oils by oxidative spectroscopic index and MCR-ALS chemometric method.  

PubMed

One of the most suitable analytical techniques used for edible oil quality control is Fourier transform mid infrared spectroscopy (FT-MIR). FT-MIR spectroscopy was used to continuously characterize the aging of various edible oils thanks to a specific aging cell. There were differences in the spectra of fresh and aged oils from different vegetable sources, which provide the basis of a method to classify them according to the oxidative spectroscopic index value. The use of chemometric treatment such as multivariate curve resolution-alternative least square (MCR-ALS) made it possible to extract the spectra of main formed and degraded species. The concentration profiles gave interesting information about the ability of the various oils to support the oxidative treatment and showed that all oils present the same aging process. Both methods led to concordant results in terms of induction times determined by the oxidative spectroscopic index and the appearance of oxidation products revealed by MCR-ALS. PMID:19159793

Le Dréau, Y; Dupuy, N; Artaud, J; Ollivier, D; Kister, J

2009-03-15

67

Cellulose crystallinity and ordering of hemicelluloses in pine and birch pulps as revealed by solid-state NMR spectroscopic methods  

Microsoft Academic Search

Solid-state 13C NMR spectroscopy was used to determine the degree of cellulose crystallinity (CrI) in kraft, flow-through kraft and polysulphide–anthraquinone (PS–AQ) pulps of pine and birch containing various amounts of hemicelluloses. The applicability of acid hydrolysis and the purely spectroscopic proton spin-relaxation based spectral edition (PSRE) method to remove the interfering hemicellulose signals prior to the determination of CrI were

Tiina Liitiä; Sirkka Liisa Maunu; Bo Hortling; Tarja Tamminen; Osmo Pekkala; Antero Varhimo

2003-01-01

68

Mesh Deformation Based on Fully Stressed Design: The Method and Two-Dimensional Examples  

NASA Technical Reports Server (NTRS)

Mesh deformation in response to redefined boundary geometry is a frequently encountered task in shape optimization and analysis of fluid-structure interaction. We propose a simple and concise method for deforming meshes defined with three-node triangular or four-node tetrahedral elements. The mesh deformation method is suitable for large boundary movement. The approach requires two consecutive linear elastic finite-element analyses of an isotropic continuum using a prescribed displacement at the mesh boundaries. The first analysis is performed with homogeneous elastic property and the second with inhomogeneous elastic property. The fully stressed design is employed with a vanishing Poisson s ratio and a proposed form of equivalent strain (modified Tresca equivalent strain) to calculate, from the strain result of the first analysis, the element-specific Young s modulus for the second analysis. The theoretical aspect of the proposed method, its convenient numerical implementation using a typical linear elastic finite-element code in conjunction with very minor extra coding for data processing, and results for examples of large deformation of two-dimensional meshes are presented in this paper. KEY WORDS: Mesh deformation, shape optimization, fluid-structure interaction, fully stressed design, finite-element analysis, linear elasticity, strain failure, equivalent strain, Tresca failure criterion

Hsu, Su-Yuen; Chang, Chau-Lyan

2007-01-01

69

Determining uranium speciation in contaminated soils by molecular spectroscopic methods: Examples from the Uranium in Soils Integrated Demonstration  

SciTech Connect

The US Department of Energy`s former uranium production facility located at Fernald, OH (18 mi NW of Cincinnati) is the host site for an Integrated Demonstration for remediation of uranium-contaminated soils. A wide variety of source terms for uranium contamination have been identified reflecting the diversity of operations at the facility. Most of the uranium contamination is contained in the top {approximately}1/2 m of soil, but uranium has been found in perched waters indicating substantial migration. In support of the development of remediation technologies and risk assessment, we are conducting uranium speciation studies on untreated and treated soils using molecular spectroscopies. Untreated soils from five discrete sites have been analyzed. We have found that {approximately}80--90% of the uranium exists as hexavalent UO{sub 2}{sup 2+} species even though many source terms consisted of tetravalent uranium species such as UO{sub 2}. Much of the uranium exists as microcrystalline precipitates (secondary minerals). There is also clear evidence for variations in uranium species from the microscopic to the macroscopic scale. However, similarities in speciation at sites having different source terms suggest that soil and groundwater chemistry may be as important as source term in defining the uranium speciation in these soils. Characterization of treated soils has focused on materials from two sites that have undergone leaching using conventional extractants (e.g., carbonate, citrate) or novel chelators such as Tiron. Redox reagents have also been used to facilitate the leaching process. Three different classes of treated soils have been identified based on the speciation of uranium remaining in the soils. In general, the effective treatments decrease the total uranium while increasing the ratio of U(IV) to U(VI) species.

Allen, P.G.; Berg, J.M.; Chisholm-Brause, C.J.; Conradson, S.D.; Donohoe, R.J.; Morris, D.E.; Musgrave, J.A.; Tait, C.D.

1994-03-01

70

Molecular structures of gas-phase polyatomic molecules determined by spectroscopic methods  

Microsoft Academic Search

Spectroscopic data related to the structures of polyatomic molecules in the gas phase have been reviewed, critically evaluated, and compiled. All reported bond distances and angles have been classified as equilibrium (re), average (rz), substitution (rs), or effective (ro) parameters, and have been given a quality rating which is a measure of the parameter uncertainty. The surveyed literature includes work

Marlin D. Harmony; Victor W. Laurie; Robert L. Kuczkowski; R. H. Schwendeman; D. A. Ramsay; Frank J. Lovas; Walter J. Lafferty; Arthur G. Maki

1979-01-01

71

[Development of the automated Patlak plot method and its verification in clinical examples].  

PubMed

The Patlak plot method is widely used in general clinical practice to calculate mean cerebral blood flow (mCBF) because it does not require arterial blood sampling and the procedure used is relatively simple. However, it has been pointed out that the calculation is affected by operator subjectivity and experience, and reproducibility is poor when the operator changes. The Patlak plot method consists of the following three procedures: (1) a region of interest (ROI) in the normal cerebral hemisphere is chosen to obtain the time-activity curve; (2) an ROI in the aortic arch is determined to obtain the time-activity curve; and (3) graphic analysis of the two time-activity curves is performed, and mCBF is determined from the slope of the graph. In this study, we automated all three of the above procedures, enabling analysis that is not affected by operator subjectivity or experience. Considering the verification result shown below: (1) automation of an ROI setup of a cerebral hemisphere and an aortic arch was possible in all examples; (2) the point of graphic analysis was set in the error range of 1% - 2% of straight line domains; (3) in comparison with the conventional method in 55 cases, the mean of absolute percentage error was 3.1+/-2.5%; (4) in 17 cases that did not accept a right-and-left difference in SPECT, the mean of absolute percentage error of right and left mCBF was 1.3+/-0.9%. It was thought that the processing algorithm was appropriate. Moreover, it was thought that the technique of graphic analysis proposed for this study served as an aid to dissolution of the "ambiguity" of the Patlak plot method. PMID:17387246

Yano, Kesato; Miyasaka, Tadashi; Sato, Makoto

2007-02-20

72

Remote determination of exposure degree and iron concentration of lunar soils using VIS-NIR spectroscopic methods  

NASA Technical Reports Server (NTRS)

On the Moon, space weathering processes such as micrometeorite bombardment alter the optical properties of lunar soils. As a consequence, lunar soil optical properties are a function not only of composition, but of degree of exposure on the lunar surface as well. In order to accurately assess the compositional properties of the lunar surface using remotely acquired visible and near-infrared spectroscopic data, it is thus necessary either (1) to compare optical properties only of soils characterized by similar degrees of exposure or (2) to otherwise normalize or remove the optical effects due to exposure. Laboratory spectroscopic data for lunar soils are used to develop and test remote spectrocopic methods for determining degree of exposure and for distinguishing between the optical effects due to exposure and those due to composition. A method employing a ratio between reflectances within and outside of the 1 micrometer Fe(2+) crystal field absorption band was developed for remotely identifying highland soils that have reached a steady-state maturity. The relative optical properties of these soils are a function solely of composition and as such can be directly compared. Spectroscopic techniques for accurate quantitative determination of iron content for lunar highland soils are investigated as well. It is shown that approximations of the 1 micrometer Fe(2+) absorption band depth using few to several channel multispectral data or spectroscopic data of inadequate spectral range cannot be used with confidence for compositional analysis. However, band depth measurements derived from continuum-removed high spectral resolution data can be used to calculate the weight percent FeO and relative proportion of iron-bearing silicates in mature lunar highland and mare/highland mixture soils. A preliminary effort to calibrate telescopic band depth to laboratory soil measurements is described.

Fischer, Erich M.; Pieters, Carle M.

1994-01-01

73

The utilisation of health research in policy-making: concepts, examples and methods of assessment  

PubMed Central

The importance of health research utilisation in policy-making, and of understanding the mechanisms involved, is increasingly recognised. Recent reports calling for more resources to improve health in developing countries, and global pressures for accountability, draw greater attention to research-informed policy-making. Key utilisation issues have been described for at least twenty years, but the growing focus on health research systems creates additional dimensions. The utilisation of health research in policy-making should contribute to policies that may eventually lead to desired outcomes, including health gains. In this article, exploration of these issues is combined with a review of various forms of policy-making. When this is linked to analysis of different types of health research, it assists in building a comprehensive account of the diverse meanings of research utilisation. Previous studies report methods and conceptual frameworks that have been applied, if with varying degrees of success, to record utilisation in policy-making. These studies reveal various examples of research impact within a general picture of underutilisation. Factors potentially enhancing utilisation can be identified by exploration of: priority setting; activities of the health research system at the interface between research and policy-making; and the role of the recipients, or 'receptors', of health research. An interfaces and receptors model provides a framework for analysis. Recommendations about possible methods for assessing health research utilisation follow identification of the purposes of such assessments. Our conclusion is that research utilisation can be better understood, and enhanced, by developing assessment methods informed by conceptual analysis and review of previous studies. PMID:12646071

Hanney, Stephen R; Gonzalez-Block, Miguel A; Buxton, Martin J; Kogan, Maurice

2003-01-01

74

Measuring maps graphical density via digital image processing method on the example of city maps  

NASA Astrophysics Data System (ADS)

During the centuries the main problem on mapping was to obtain the sufficient and reliable source data; presently, an appropriate selection of the desired information from the deluge of available data I a problem. An availability of large amount of data induces to transfer the possibly rich information by mean of map. It often results in overloading the cartographic documents, that is why they become less communicative and difficult to read. This situation is well illustrated by the example of city maps which are the most commonly used and thus the most frequently published cartographic products. Many user groups with different needs as well as preparation to read maps use these high volume publications. Therefore, the maps communication effectiveness problem is of particular importance. The city maps are the most complex cartographic presentations, because the presented areas are the places with the greatest concentration of different kinds of objects and forms of human activity arising from the civilization development. Conveying these specific features on the city maps leads to the problem of selecting the most relevant elements of content in terms of user's needs, since presenting all objects and their characteristics is impossible if the city map readability is to be kept. Although complexity has been the cartographers' object of interest for many years, because it exerts an impact on readability and effectiveness of cartographic documents, none of the measures used so far may be applied for automatic determination of complexity of such graphically complicated objects as city maps. Therefore a novel approach was needed for these applications. For that purpose digital image processing techniques have been proposed and successfully applied by the authors. The analysis of the spatial distribution of the objects' edges on the map surface, calculated using continuous wavelet transform, is the basis of the proposed measure. The method allows for comparison of complexity of city maps loaded by different type of graphical elements (point signatures, lines, text, etc.). Extended analyses of selected cartographic materials proved the usability of the method for quantitative estimation of city map complexity via formal index

Ciolkosz-Styk, A.; Styk, A.

2012-06-01

75

The spectroscopic and electronic properties of dimethylpyrazole and its derivatives using the experimental and computational methods.  

PubMed

In this paper the spectroscopic and the geometric properties of four ligands with pyrazole unit are studied at both experimental and computational levels. The computational results are perfectly in good agreement with the experimental results especially in terms of the IR, H-NMR and 13C-NMR shifts. The spectroscopic features as well as the computed properties help to establish the successful synthesis of ligands bdmpzm and bdmpza. The theoretical and the experimental IR and Raman significantly help in distinguishing the four ligands. The results show that the Raman spectral is better applicable in characterising the CH3 deformation, the C-H, CNN and CCNNout of the ligands but vibrations like N-H in dmpz and O-H, C=O in bdmpza are observed to be Raman inactive. A significant variations are observed among the two available * N atoms characterising the bidentate features of bdmpzm, bdmpza and bdcpzm which indicates a possible different affinities for metal coordination: Also the result suggest that bdmpza will be the best starting material for NLO application than other while bdcpzm is predicted to have potential of been a poor coordinating ligand. The computed variations in the properties of * N atoms that are the characteristic features of their power of coordination can be of immense help since these type of ligands have a wide application in transition metal coordination. PMID:25532317

Adeniyi, Adebayo A; Ajibade, Peter A

2014-09-01

76

Structural, Spectroscopic, and Magnetic Properties of Eu(3+)-Doped GdVO4 Nanocrystals Synthesized by a Hydrothermal Method.  

PubMed

New interesting aspects of the spectroscopic properties, magnetism, and method of synthesis of gadolinium orthovanadates doped with Eu(3+) ions are discussed. Gd1-xEuxVO4 (x = 0, 0.05, 0.2) bifunctional luminescent materials with complex magnetic properties were synthesized by a microwave-assisted hydrothermal method. Products were formed in situ without previous precipitation. The crystal structures and morphologies of the obtained nanomaterials were analyzed by X-ray diffraction and transmission and scanning electron microscopy. Crystallographic data were analyzed using Rietveld refinement. The products obtained were nanocrystalline with average grain sizes of 70-80 nm. The qualitative and quantitative elemental composition as well as mapping of the nanocrystals was proved using energy-dispersive X-ray spectroscopy. The spectroscopic properties of red-emitting nanophosphors were characterized by their excitation and emission spectra and luminescence decays. Magnetic measurements were performed by means of vibrating sample magnetometry. GdVO4 and Gd0.8Eu0.2VO4 exhibited paramagnetic behavior with a weak influence of antiferromagnetic couplings between rare-earth ions. In the substituted sample, an additional magnetic contribution connected with the population of low-lying excited states of europium was observed. PMID:25383487

Szczeszak, Agata; Grzyb, Tomasz; Sniadecki, Zbigniew; Andrzejewska, Nina; Lis, Stefan; Matczak, Micha?; Nowaczyk, Grzegorz; Jurga, Stefan; Idzikowski, Bogdan

2014-12-01

77

Raman Spectroscopic Methods for Classification of Normal and Malignant Hypopharyngeal Tissues: An Exploratory Study  

PubMed Central

Laryngeal cancer is more common in males. The present study is aimed at exploration of potential of conventional Raman spectroscopy in classifying normal from a malignant laryngopharyngeal tissue. We have recorded Raman spectra of twenty tissues (aryepiglottic fold) using an in-house built Raman setup. The spectral features of mean malignant spectrum suggests abundance proteins whereas spectral features of mean normal spectrum indicate redundancy of lipids. PCA was employed as discriminating algorithm. Both, unsupervised and supervised modes of analysis as well as match/mismatch “limit test” methodology yielded clear classification among tissue types. The findings of this study demonstrate the efficacy of conventional Raman spectroscopy in classification of normal and malignant laryngopharyngeal tissues. A rigorous evaluation of the models with development of suitable fibreoptic probe may enable real-time Raman spectroscopic diagnosis of laryngopharyngeal cancers in future. PMID:21804932

Pujary, Parul; Maheedhar, K.; Krishna, C. Murali; Pujary, Kailesh

2011-01-01

78

Determining uranium speciation in Fernald soils by molecular spectroscopic methods. FY 1993 progress report  

SciTech Connect

This progress report describes new experimental results and interpretations for data collected from October 1, 1992, through September 30, 1993, as part of the Characterization Task of the Uranium in Soils Integrated Demonstration of the Office of Technology Development, Office of Environmental Restoration and Waste Management of the US Department of Energy. X-ray absorption, optical luminescence, and Raman vibrational spectroscopies were used to determine uranium speciation in contaminated soils from the US DOE`s former uranium production facility at Fernald, Ohio. These analyses were carried out both before and after application of one of the various decontamination technologies being developed within the Integrated Demonstration. This year the program focused on characterization of the uranium speciation remaining in the soils after decontamination treatment. X-ray absorption and optical luminescence spectroscopic data were collected for approximately 40 Fernald soil samples, which were treated by one or more of the decontamination technologies.

Allen, P.G.; Berg, J.M.; Crisholm-Brause, C.J.; Conradson, S.D.; Donohoe, R.J.; Morris, D.E.; Musgrave, J.A.; Tait, C.D.

1994-07-01

79

Study of the interaction between esculetin and human serum albumin by multi-spectroscopic method and molecular modeling  

NASA Astrophysics Data System (ADS)

Esculetin derived from Cortex fraxin plays an important role as a traditional Chinese medicine because of its unique pharmacological properties. The interactions between esculetin and HSA were studied by fluorescence spectroscopic techniques under similar to human physiologic conditions. The binding parameters have been evaluated by fluorescence quenching methods. The results proved the mechanism of fluorescence quenching of HSA while interacting with esculetin is due to the formation of esculetin-HSA complex formation. The thermodynamic parameters like ? H0 and ? S0 were calculated to be -14.62 kJ/mol and 38.93 J/mol/K, respectively, which proves main interaction between esculetin and HSA is hydrophobic contact, but the electrostatic interaction cannot be excluded, which in agreement with the result of molecular docking study. The distance r between donor (HSA) and acceptor (esculetin) was obtained according to the Förster's theory of non-radiative energy transfer and found to be 2.89 nm. From the high value of fluorescence anisotropy ( r = 0.07) it was argued that the probe molecular was located in motionally restricted environment of the protein. The alterations of protein secondary structure in the presence of esculetin were confirmed by the evidences from UV, FT-IR and CD spectroscopes. In addition, the effects of common ions and amino acids on the constants of esculetin-HSA complex were also discussed.

Yue, Yuanyuan; Zhang, Yaheng; Qin, Jin; Chen, Xingguo

2008-10-01

80

Vibrational spectroscopic methods to characterize the bionanoparticles originating from newly developed self-forming synthetic PEGylated lipids (QuSomes)  

NASA Astrophysics Data System (ADS)

Vibrational spectroscopy has been used to elucidate the temperature dependence of structural and conformational changes in lipids and liposomes. In this work, the thermal properties of lipid-based nanovesicles originating from a newly developed self-forming synthetic PEGylated lipids has been investigated by variable-temperature Fourier-transform infrared (FTIR) absorption and Raman spectroscopic methods. Thermally-induced changes in infrared and Raman spectra of these artificial lipid based nanovesicles composed of 1,2-dimyristoyl-rac-glycerol-3-dodecaethylene glycol (GDM-12) and 1,2-distearoyl-rac-glycerol-3-triicosaethylene glycol (GDS-23) were acquired by using a thin layered FTIR spectrometer in conjunction with a unique custom built temperature-controlled demountable liquid cell and variable-temperature controlled Raman microscope, respectively. The lipids under consideration have long hydrophobic acyl chains and contain various units of hydrophilic polyethylene glycol headgroups. In contrast to conventional phospholipids, this new kind of lipid is forming liposomes or nanovesicles spontaneously upon hydration, without supplying external activation energy. We have found that the thermal stability of such PEGylated lipids and nanovesicles differs greatly depending upon the acyl chain-lengths as well as associated head group units. However, the thermal behavior observed from both spectroscopic vibrational techniques are in good agreement.

Bista, Rajan K.; Bruch, Reinhard F.; Covington, Aaron M.

2011-03-01

81

Specific binding and inhibition of 6-benzylaminopurine to catalase: multiple spectroscopic methods combined with molecular docking study.  

PubMed

6-Benzylaminopurine (6-BA) is a kind of cytokinin which could regulate the activities of the antioxidant defense system of plants. In this work, its interaction with and inhibition of beef liver catalase have been systematically investigated using spectroscopic, isothermal titration calorimetric and molecular docking methods under physiological conditions. The fluorescence quenching of beef liver catalase (BLC) by 6-BA is due to the formation of 6-BA-BLC complex. Hydrogen bonds and van der Waals interactions play major roles in stabilizing the complex. The Stern-Volmer quenching constant, binding constant, the corresponding thermodynamic parameters and binding numbers were measured. The results of UV-vis absorption, three-dimensional fluorescence, synchronous fluorescence and circular dichroism spectroscopic results demonstrate that the binding of 6-BA results in the micro-environment change around tyrosine (Tyr) and tryptophan (Trp) residues of BLC. The BLC-mediated conversion of H2O2 to H2O and O2, in the presence and absence of 6-BA, was also studied. Lineweaver-Burk plot indicates a noncompetitive type of inhibition. Molecular docking study was used to find the binding sites. PMID:24412785

Xu, Qin; Lu, Yanni; Jing, Longyun; Cai, Lijuan; Zhu, Xinfeng; Xie, Ju; Hu, Xiaoya

2014-04-01

82

Integrating case study and survey research methods: an example in information systems  

Microsoft Academic Search

The case for combining research methods generally, and more specifically that for combining qualitative and quantitative methods, is strong. Yet, research designs that extensively integrate both fieldwork (e.g. case studies) and survey research are rare. Moreover, some journals tend tacitly to specialize by methodology thereby encouraging purity of method. The multi-method model of research while not new, has not been

Guy G. Gable

1994-01-01

83

Comparison of Methods Used to Estimate Conventional Undiscovered Petroleum Resources: World Examples  

Microsoft Academic Search

Various methods for assessing undiscovered oil, natural gas, and natural gas liquid resources were compared in support of the USGS World Petroleum Assessment 2000. Discovery process, linear fractal, parabolic fractal, engineering estimates, PETRIMES, Delphi, and the USGS 2000 methods were compared. Three comparisons of these methods were made in: (1) the Neuquen Basin province, Argentina (different assessors, same input data);

Thomas S. Ahlbrandt; T. R. Klett

2005-01-01

84

Interaction of tetramethylpyrazine with two serum albumins by a hybrid spectroscopic method  

NASA Astrophysics Data System (ADS)

The interactions of tetramethylpyrazine (TMPZ) with bovine serum albumin (BSA) and human serum albumin (HSA) have been investigated by various spectroscopic techniques. Fluorescence tests showed that TMPZ could bind to BSA/HSA to form complexes. The binding constants of TMPZ-BSA and TMPZ-HSA complexes were observed to be 1.442 × 104 and 3.302 × 104 M-1 at 298 K, respectively. The thermodynamic parameters (?G, ?H and ?S) calculated on the basis of different temperatures revealed that the binding of TMPZ-HSA was mainly depended on hydrophobic interaction, and yet the binding of TMPZ-BSA might involve hydrophobic interaction strongly and electrostatic interaction. The results of synchronous fluorescence, three-dimensional fluorescence, UV-vis absorption, FT-IR and CD spectra showed that the conformations of both BSA and HSA altered with the addition of TMPZ. The binding average distance between TMPZ and BSA/HSA was evaluated according to Föster non-radioactive energy transfer theory. In addition, with the aid of site markers (such as, phenylbutazone, ibuprofen and digitoxin), TMPZ primarily bound to tryptophan residues of BSA/HSA within site I (sub-domain II A).

Cheng, Zhengjun

85

Studies on the interaction of apigenin with calf thymus DNA by spectroscopic methods  

NASA Astrophysics Data System (ADS)

The interaction between apigenin and calf thymus deoxyribonucleic acid (ctDNA) in a pH 7.4 Tris-HCl buffer solution was investigated by UV-Vis spectroscopy, fluorescence spectroscopy, DNA melting techniques, and viscosity measurements. It was found that apigenin molecules could intercalate into the base pairs of DNA, forming a apigenin-DNA complex with a binding constant of K310K = 6.4 × 104 L mol-1. The thermodynamic parameters enthalpy change (?H), entropy change (?S) and Gibbs free energy (?G) were calculated to be 7.36 × 104 J mol-1, 329 J K-1 mol-1 and -2.84 × 104 J mol-1 at 310 K, respectively. Hydrophobic interaction was the predominant intermolecular force in stabilizing the apigenin-DNA complex. Thermal denaturation study suggested that the stabilization of the ctDNA helix was increased when the apigenin binding to ctDNA as indicated by the increase in thermal denaturation temperature of ctDNA at around 5.0 °C in the presence of apigenin. Spectroscopic techniques together with melting techniques and viscosity determination provided evidences of intercalation mode of binding for the interaction between apigenin and ctDNA.

Zhang, Shufang; Sun, Xuejun; Kong, Rongmei; Xu, Mingming

2015-02-01

86

Interaction of Bioactive Coomassie Brilliant Blue G with Protein: Insights from Spectroscopic Methods  

PubMed Central

The binding of coomassie brilliant blue G (CBB) to bovine serum albumin (BSA) was investigated under simulative physiological conditions employing different optical spectroscopic techniques viz., fluorescence emission, UV–visible absorption and FTIR. Fluorescence quenching data obtained at different temperatures suggested the presence of dynamic type of quenching mechanism. The binding constant of CBB-BSA and the number of binding sites (n) for CBB in BSA were calculated and found to be 4.20 × 104 M?1 and 0.96 respectively, at 302 K. The value of n close to unity indicated that the protein has a single class of binding sites for CBB. The thermodynamic parameters revealed that the hydrophobic forces played a major role in the interaction of CBB to BSA. The distance between the CBB and protein was calculated using the theory of Föster’s Resonance Energy Transfer (FRET). The conformational change in the secondary structure of BSA upon interaction with dye was investigated by synchronous fluorescence and FTIR techniques. Competitive binding studies were also carried out to know the location of binding of CBB on BSA. PMID:21179322

Katrahalli, Umesha; Kalanur, Shankara Sharanappa; Seetharamappa, Jaladappagari

2010-01-01

87

The spectroscopic and the QTAIM properties of pyridine and phenanthroline derivatives using experimental and computational methods.  

PubMed

The experimental and theoretical properties of ligands consisting of pyridine and phenanthroline derivatives have been studied. The results show a very high correlation between the experimental and theoretical spectroscopic properties of the ligands such as the IR, NMR chemical shift and UV. The carboxylic units in the ligands lead to increase in the dipole and anisotropic properties of the molecules while the methyl group lead to increase in the isotropic shielding tensor of the molecules. Most of the observed UV ?max in the ligands are predominantly excitation of electrons from the HOMO-2 or HOMO-1 or HOMO to the LUMO of the ligands. The ligand 2,2-dicarboxylphenanthroline (dcphn) is predicted to be the best starting material for non-linear optical (NLO) application due to its far higher first static hyperpolarizability tensor compare to other ligands and its lowest band gap. The same ligand can also be best for DNA binding because it has the lowest value of LUMO. The atomic charge of the nitrogen is found to be highly correlated with molecular HOMO, LUMO and non-Lewis orbital. The (15)N NMR chemical shift is found to be highly correlated atomic anisotropy, energy and intra-atomic isotropic shielding tensor. PMID:24691368

Adeniyi, Adebayo A; Ajibade, Peter A

2014-07-15

88

Interaction of erucic acid with bovine serum albumin using a multi-spectroscopic method and molecular docking technique.  

PubMed

Overconsumption of erucic acid has been shown to cause heart damage in animals. The aim of this study is to evaluate the binding behaviour between erucic acid and bovine serum albumin using multi-spectroscopic methods and a molecular docking technique under physiological conditions. We find that erucic acid can quench the intrinsic fluorescence of BSA by dynamic quenching and there is a single class of binding site on BSA. In addition, the thermodynamic functions ?H and ?S are 119.14kJmol(-1) and 488.89Jmol(-1)K(-1), indicating that the hydrophobic force is a main acting force. Furthermore, the protein secondary structure changes with an increase in the content of ?-helix, measured using synchronous fluorescence, circular dichroism and Fourier transform infrared spectroscopies. The molecular docking results illustrate that erucic acid can bind with the subdomain IIA of the BSA, and hydrogen bonding is also an acting force. PMID:25465991

Shu, Yang; Xue, Weiwei; Xu, Xiaoying; Jia, Zhimin; Yao, Xiaojun; Liu, Shuwen; Liu, Lihong

2015-04-15

89

Comparison of methods used to estimate conventional undiscovered petroleum resources: World examples  

USGS Publications Warehouse

Various methods for assessing undiscovered oil, natural gas, and natural gas liquid resources were compared in support of the USGS World Petroleum Assessment 2000. Discovery process, linear fractal, parabolic fractal, engineering estimates, PETRIMES, Delphi, and the USGS 2000 methods were compared. Three comparisons of these methods were made in: (1) the Neuquen Basin province, Argentina (different assessors, same input data); (2) provinces in North Africa, Oman, and Yemen (same assessors, different methods); and (3) the Arabian Peninsula, Arabian (Persian) Gulf, and North Sea (different assessors, different methods). A fourth comparison (same assessors, same assessment methods but different geologic models), between results from structural and stratigraphic assessment units in the North Sea used only the USGS 2000 method, and hence compared the type of assessment unit rather than the method. In comparing methods, differences arise from inherent differences in assumptions regarding: (1) the underlying distribution of the parent field population (all fields, discovered and undiscovered), (2) the population of fields being estimated; that is, the entire parent distribution or the undiscovered resource distribution, (3) inclusion or exclusion of large outlier fields; (4) inclusion or exclusion of field (reserve) growth, (5) deterministic or probabilistic models, (6) data requirements, and (7) scale and time frame of the assessment. Discovery process, Delphi subjective consensus, and the USGS 2000 method yield comparable results because similar procedures are employed. In mature areas such as the Neuquen Basin province in Argentina, the linear and parabolic fractal and engineering methods were conservative compared to the other five methods and relative to new reserve additions there since 1995. The PETRIMES method gave the most optimistic estimates in the Neuquen Basin. In less mature areas, the linear fractal method yielded larger estimates relative to other methods. A geologically based model, such as one using the total petroleum system approach, is preferred in that it combines the elements of petroleum source, reservoir, trap and seal with the tectono-stratigraphic history of basin evolution with petroleum resource potential. Care must be taken to demonstrate that homogeneous populations in terms of geology, geologic risk, exploration, and discovery processes are used in the assessment process. The USGS 2000 method (7th Approximation Model, EMC computational program) is robust; that is, it can be used in both mature and immature areas, and provides comparable results when using different geologic models (e.g. stratigraphic or structural) with differing amounts of subdivisions, assessment units, within the total petroleum system. ?? 2005 International Association for Mathematical Geology.

Ahlbrandt, T.S.; Klett, T.R.

2005-01-01

90

Spectroscopic methods of process monitoring for safeguards of used nuclear fuel separations  

NASA Astrophysics Data System (ADS)

To support the demonstration of a more proliferation-resistant nuclear fuel processing plant, techniques and instrumentation to allow the real-time, online determination of special nuclear material concentrations in-process must be developed. An ideal materials accountability technique for proliferation resistance should provide nondestructive, realtime, on-line information of metal and ligand concentrations in separations streams without perturbing the process. UV-Visible spectroscopy can be adapted for this precise purpose in solvent extraction-based separations. The primary goal of this project is to understand fundamental URanium EXtraction (UREX) and Plutonium-URanium EXtraction (PUREX) reprocessing chemistry and corresponding UV-Visible spectroscopy for application in process monitoring for safeguards. By evaluating the impact of process conditions, such as acid concentration, metal concentration and flow rate, on the sensitivity of the UV-Visible detection system, the process-monitoring concept is developed from an advanced application of fundamental spectroscopy. Systematic benchtop-scale studies investigated the system relevant to UREX or PUREX type reprocessing systems, encompassing 0.01-1.26 M U and 0.01-8 M HNO3. A laboratory-scale TRansUranic Extraction (TRUEX) demonstration was performed and used both to analyze for potential online monitoring opportunities in the TRUEX process, and to provide the foundation for building and demonstrating a laboratory-scale UREX demonstration. The secondary goal of the project is to simulate a diversion scenario in UREX and successfully detect changes in metal concentration and solution chemistry in a counter current contactor system with a UV-Visible spectroscopic process monitor. UREX uses the same basic solvent extraction flowsheet as PUREX, but has a lower acid concentration throughout and adds acetohydroxamic acid (AHA) as a complexant/reductant to the feed solution to prevent the extraction of Pu. By examining UV-Visible spectra gathered in real time, the objective is to detect the conversion from the UREX process, which does not separate Pu, to the PUREX process, which yields a purified Pu product. The change in process chemistry can be detected in the feed solution, aqueous product or in the raffinate stream by identifying the acid concentration, metal distribution and the presence or absence of AHA. A fiber optic dip probe for UV-Visible spectroscopy was integrated into a bank of three counter-current centrifugal contactors to demonstrate the online process monitoring concept. Nd, Fe and Zr were added to the uranyl nitrate system to explore spectroscopic interferences and identify additional species as candidates for online monitoring. This milestone is a demonstration of the potential of this technique, which lies in the ability to simultaneously and directly monitor the chemical process conditions in a reprocessing plant, providing inspectors with another tool to detect nuclear material diversion attempts. Lastly, dry processing of used nuclear fuel is often used as a head-end step before solvent extraction-based separations such as UREX or TRUEX. A non-aqueous process, used fuel treatment by dry processing generally includes chopping of used fuel rods followed by repeated oxidation-reduction cycles and physical separation of the used fuel from the cladding. Thus, dry processing techniques are investigated and opportunities for online monitoring are proposed for continuation of this work in future studies.

Warburton, Jamie Lee

91

A method to derive vegetation distribution maps for pollen dispersion models using birch as an example  

NASA Astrophysics Data System (ADS)

Detailed knowledge of the spatial distribution of sources is a crucial prerequisite for the application of pollen dispersion models such as, for example, COSMO-ART (COnsortium for Small-scale MOdeling - Aerosols and Reactive Trace gases). However, this input is not available for the allergy-relevant species such as hazel, alder, birch, grass or ragweed. Hence, plant distribution datasets need to be derived from suitable sources. We present an approach to produce such a dataset from existing sources using birch as an example. The basic idea is to construct a birch dataset using a region with good data coverage for calibration and then to extrapolate this relationship to a larger area by using land use classes. We use the Swiss forest inventory (1 km resolution) in combination with a 74-category land use dataset that covers the non-forested areas of Switzerland as well (resolution 100 m). Then we assign birch density categories of 0%, 0.1%, 0.5% and 2.5% to each of the 74 land use categories. The combination of this derived dataset with the birch distribution from the forest inventory yields a fairly accurate birch distribution encompassing entire Switzerland. The land use categories of the Global Land Cover 2000 (GLC2000; Global Land Cover 2000 database, 2003, European Commission, Joint Research Centre; resolution 1 km) are then calibrated with the Swiss dataset in order to derive a Europe-wide birch distribution dataset and aggregated onto the 7 km COSMO-ART grid. This procedure thus assumes that a certain GLC2000 land use category has the same birch density wherever it may occur in Europe. In order to reduce the strict application of this crucial assumption, the birch density distribution as obtained from the previous steps is weighted using the mean Seasonal Pollen Index (SPI; yearly sums of daily pollen concentrations). For future improvement, region-specific birch densities for the GLC2000 categories could be integrated into the mapping procedure.

Pauling, A.; Rotach, M. W.; Gehrig, R.; Clot, B.

2012-09-01

92

A new method of discovering primary management history: two examples where “little things mean a lot”  

Microsoft Academic Search

Outlines a new method of discovering original documents related to management history. Uses seemingly insignificant statements in books, articles or original documents to locate documents not listed on any computer database or public archive records, but which are undiscovered in attics or basements. The method involves the use of sources not commonly used by management scholars: obituaries, wills, cemetery records,

Charles D. Wrege; Ronald G. Greenwood; Regina Greenwood

1997-01-01

93

A method to derive vegetation distribution maps for pollen dispersion models using birch as an example.  

PubMed

Detailed knowledge of the spatial distribution of sources is a crucial prerequisite for the application of pollen dispersion models such as, for example, COSMO-ART (COnsortium for Small-scale MOdeling-Aerosols and Reactive Trace gases). However, this input is not available for the allergy-relevant species such as hazel, alder, birch, grass or ragweed. Hence, plant distribution datasets need to be derived from suitable sources. We present an approach to produce such a dataset from existing sources using birch as an example. The basic idea is to construct a birch dataset using a region with good data coverage for calibration and then to extrapolate this relationship to a larger area by using land use classes. We use the Swiss forest inventory (1 km resolution) in combination with a 74-category land use dataset that covers the non-forested areas of Switzerland as well (resolution 100 m). Then we assign birch density categories of 0%, 0.1%, 0.5% and 2.5% to each of the 74 land use categories. The combination of this derived dataset with the birch distribution from the forest inventory yields a fairly accurate birch distribution encompassing entire Switzerland. The land use categories of the Global Land Cover 2000 (GLC2000; Global Land Cover 2000 database, 2003, European Commission, Joint Research Centre; resolution 1 km) are then calibrated with the Swiss dataset in order to derive a Europe-wide birch distribution dataset and aggregated onto the 7 km COSMO-ART grid. This procedure thus assumes that a certain GLC2000 land use category has the same birch density wherever it may occur in Europe. In order to reduce the strict application of this crucial assumption, the birch density distribution as obtained from the previous steps is weighted using the mean Seasonal Pollen Index (SPI; yearly sums of daily pollen concentrations). For future improvement, region-specific birch densities for the GLC2000 categories could be integrated into the mapping procedure. PMID:22086367

Pauling, A; Rotach, M W; Gehrig, R; Clot, B

2012-09-01

94

Mouse ENU Mutagenesis to Understand Immunity to Infection: Methods, Selected Examples, and Perspectives  

PubMed Central

Infectious diseases are responsible for over 25% of deaths globally, but many more individuals are exposed to deadly pathogens. The outcome of infection results from a set of diverse factors including pathogen virulence factors, the environment, and the genetic make-up of the host. The completion of the human reference genome sequence in 2004 along with technological advances have tremendously accelerated and renovated the tools to study the genetic etiology of infectious diseases in humans and its best characterized mammalian model, the mouse. Advancements in mouse genomic resources have accelerated genome-wide functional approaches, such as gene-driven and phenotype-driven mutagenesis, bringing to the fore the use of mouse models that reproduce accurately many aspects of the pathogenesis of human infectious diseases. Treatment with the mutagen N-ethyl-N-nitrosourea (ENU) has become the most popular phenotype-driven approach. Our team and others have employed mouse ENU mutagenesis to identify host genes that directly impact susceptibility to pathogens of global significance. In this review, we first describe the strategies and tools used in mouse genetics to understand immunity to infection with special emphasis on chemical mutagenesis of the mouse germ-line together with current strategies to efficiently identify functional mutations using next generation sequencing. Then, we highlight illustrative examples of genes, proteins, and cellular signatures that have been revealed by ENU screens and have been shown to be involved in susceptibility or resistance to infectious diseases caused by parasites, bacteria, and viruses. PMID:25268389

Caignard, Grégory; Eva, Megan M.; van Bruggen, Rebekah; Eveleigh, Robert; Bourque, Guillaume; Malo, Danielle; Gros, Philippe; Vidal, Silvia M.

2014-01-01

95

Composite analysis with Monte Carlo methods: an example with cosmic rays and clouds  

NASA Astrophysics Data System (ADS)

The composite (superposed epoch) analysis technique has been frequently employed to examine a hypothesized link between solar activity and the Earth's atmosphere, often through an investigation of Forbush decrease (Fd) events (sudden high-magnitude decreases in the flux cosmic rays impinging on the upper-atmosphere lasting up to several days). This technique is useful for isolating low-amplitude signals within data where background variability would otherwise obscure detection. The application of composite analyses to investigate the possible impacts of Fd events involves a statistical examination of time-dependent atmospheric responses to Fds often from aerosol and/or cloud datasets. Despite the publication of numerous results within this field, clear conclusions have yet to be drawn and much ambiguity and disagreement still remain. In this paper, we argue that the conflicting findings of composite studies within this field relate to methodological differences in the manner in which the composites have been constructed and analyzed. Working from an example, we show how a composite may be objectively constructed to maximize signal detection, robustly identify statistical significance, and quantify the lower-limit uncertainty related to hypothesis testing. Additionally, we also demonstrate how a seemingly significant false positive may be obtained from non-significant data by minor alterations to methodological approaches.

Laken, B. A.; ?alogovi?, J.

2013-09-01

96

Theoretical assessment of 3-D magnetotelluric method for oil and gas exploration: Synthetic examples  

NASA Astrophysics Data System (ADS)

In petroleum explorations, seismic reflection technique has been almost always the preferred method for its high exploration depth and resolution. However, with the development of three dimensional (3D) inversion and interpretation schemes, much potential has been shown in MT method dealing with complex geological structures as in oil and gas exploration. In this study, synthetic geophysical models of petroleum reservoir structures are modeled and utilized to demonstrate that feasibility of 3-D MT technique for hydrocarbon exploration. A series of typical reservoir structure models are constructed and used to generate synthetic MT and seismic data to test the capabilities of 2-D/3-D MT and 2-D seismic inversion techniques. According to the inversion comparison, in addition to correctly retrieve the original forward model, the 3-D MT method also has some advantages over the reflective seismology method, which suffered from the lack of reflection wave and multiple wave problems. With the presented 3-D high resolution MT inversion method, MT techniques should be employed as one of the first choices for petroleum explorations.

Zhang, Kun; Wei, Wenbo; Lu, Qingtian; Dong, Hao; Li, Yanqing

2014-07-01

97

Methods of Fitting a Straight Line to Data: Examples in Water Resources  

USGS Publications Warehouse

Three methods of fitting straight lines to data are described and their purposes are discussed and contrasted in terms of their applicability in various water resources contexts. The three methods are ordinary least squares (OLS), least normal squares (LNS), and the line of organic correlation (OC). In all three methods the parameters are based on moment statistics of the data. When estimation of an individual value is the objective, OLS is the most appropriate. When estimation of many values is the objective and one wants the set of estimates to have the appropriate variance, then OC is most appropriate. When one wishes to describe the relationship between two variables and measurement error is unimportant, then OC is most appropriate. Where the error is important in descriptive problems or in calibration problems, then structural analysis techniques may be most appropriate. Finally, if the problem is one of describing some geographic trajectory, then LNS is most appropriate.

Hirsch, Robert M.; Gilroy, Edward J.

1984-01-01

98

¹?C(n,?) ¹?C as a Test Case in the Evaluation of a New Method to Determine Spectroscopic Factors Using Asymptotic Normalization Coefficients  

E-print Network

spectroscopic factors (SFs) using the asymptotic normalization coefficient (ANC) to fix the external contribution of a nonperipheral reaction, reducing the uncertainty in the SF. The ¹?C[left right arrow]¹?C+n system was chosen as a test case for this new method...

McCleskey, Matthew Edgar

2012-02-14

99

Electron-spectroscopic imaging--a method for analysing the distribution of light elements in mammalian cells and tissues.  

PubMed

Electron-spectroscopic imaging (ESI) represents a method which is based on electron energy loss spectroscopy (EELS) and renders possible to image the spatial distribution of light and medium-weight elements, i.e. especially of biologically relevant elements. In the present study, the validity of the method for biological problems was investigated by analysing the time-dependent, subcellular distribution of titanium following treatment with the cytostatically active compound titanocene dichloride in the liver, which is known to be the organ where titanium mainly accumulates following therapy with titanocene dichloride, and in 3 xenografted human tumours which are known to be sensitive to the antitumour action of titanocene dichloride. In all cases, it was shown that titanium primarily accumulates in the nuclei of hepatocytes and tumour cells and that it is thereafter incorporated into cytoplasmic lysosomes. Interestingly, phosphorus is always enriched together with titanium. These results give remarkable hints to the cellular mode of action of titanocene dichloride and, moreover, qualify the ESI technique to be a valuable method for investigating the subcellular distribution of endogenously present or exogenously light and medium-weight element. PMID:1801512

Köpf-Maier, P

1991-01-01

100

A spectroscopic method for determining lignin content of softwood and hardwood kraft pulps  

Microsoft Academic Search

A rapid method for determining the kappa number of unbleached and oxygen-delignified kraft pulps in the range 3–35 is presented. This novel method was based on the multivariate analysis of VIS spectral data on pulp samples. The calculated models and the test results indicated that partial least squares (PLS) and principal component regression (PCR) models yielded similar results, PLS being

Petteri Malkavaara; Raimo Alén

1998-01-01

101

Monte Carlo method for determining earthquake recurrence parameters from short paleoseismic catalogs: Example calculations for California  

USGS Publications Warehouse

Paleoearthquake observations often lack enough events at a given site to directly define a probability density function (PDF) for earthquake recurrence. Sites with fewer than 10-15 intervals do not provide enough information to reliably determine the shape of the PDF using standard maximum-likelihood techniques (e.g., Ellsworth et al., 1999). In this paper I present a method that attempts to fit wide ranges of distribution parameters to short paleoseismic series. From repeated Monte Carlo draws, it becomes possible to quantitatively estimate most likely recurrence PDF parameters, and a ranked distribution of parameters is returned that can be used to assess uncertainties in hazard calculations. In tests on short synthetic earthquake series, the method gives results that cluster around the mean of the input distribution, whereas maximum likelihood methods return the sample means (e.g., NIST/SEMATECH, 2006). For short series (fewer than 10 intervals), sample means tend to reflect the median of an asymmetric recurrence distribution, possibly leading to an overestimate of the hazard should they be used in probability calculations. Therefore a Monte Carlo approach may be useful for assessing recurrence from limited paleoearthquake records. Further, the degree of functional dependence among parameters like mean recurrence interval and coefficient of variation can be established. The method is described for use with time-independent and time-dependent PDFs, and results from 19 paleoseismic sequences on strike-slip faults throughout the state of California are given.

Parsons, T.

2008-01-01

102

Monte Carlo Method for Determining Earthquake Recurrence Parameters from Short Paleoseismic Catalogs: Example Calculations for California  

USGS Publications Warehouse

Paleoearthquake observations often lack enough events at a given site to directly define a probability density function (PDF) for earthquake recurrence. Sites with fewer than 10-15 intervals do not provide enough information to reliably determine the shape of the PDF using standard maximum-likelihood techniques [e.g., Ellsworth et al., 1999]. In this paper I present a method that attempts to fit wide ranges of distribution parameters to short paleoseismic series. From repeated Monte Carlo draws, it becomes possible to quantitatively estimate most likely recurrence PDF parameters, and a ranked distribution of parameters is returned that can be used to assess uncertainties in hazard calculations. In tests on short synthetic earthquake series, the method gives results that cluster around the mean of the input distribution, whereas maximum likelihood methods return the sample means [e.g., NIST/SEMATECH, 2006]. For short series (fewer than 10 intervals), sample means tend to reflect the median of an asymmetric recurrence distribution, possibly leading to an overestimate of the hazard should they be used in probability calculations. Therefore a Monte Carlo approach may be useful for assessing recurrence from limited paleoearthquake records. Further, the degree of functional dependence among parameters like mean recurrence interval and coefficient of variation can be established. The method is described for use with time-independent and time-dependent PDF?s, and results from 19 paleoseismic sequences on strike-slip faults throughout the state of California are given.

Parsons, Tom

2008-01-01

103

Monte Carlo method for determining earthquake recurrence parameters from short paleoseismic catalogs: Example calculations  

E-print Network

Monte Carlo method for determining earthquake recurrence parameters from short paleoseismic paleoseismic series. From repeated Monte Carlo draws, it becomes possible to quantitatively estimate most to an overestimate of the hazard should they be used in probability calculations. Therefore a Monte Carlo approach

104

High-Quality Cross-Sectioning Method: Examples of Applications in Optimizing Solar Cell Contact Firing  

SciTech Connect

A damage-free polishing method is developed to prepare a high-quality cross-section of a large length of a solar cell. A 1-inch-long sample is diced from the solar cell and embedded in wax using a specially designed chuck. The sample edge is sequentially polished by progressively reducing the grit sizes. The final polishing is done by Chemical Mechanical Polishing (CMP). This polishing procedure produces a highly flat edge, with excellent interfaces between metal contacts and the Si cell. The planarity of the wafer edge makes it possible to perform a variety of analyses of various regions and the interfaces of the cell, using optical microscopy, EDX, scanning electron microscopy (SEM), and conductive AFM (C-AFM). Here, we will discuss some details of the chuck and the polishing procedure, and present some applications for optimizing the contact firing process. This method has an added advantage of delineating the back surface field for optical observation.

Sopori, B.; Sahoo, S.; Mehta, V.; Guhabiswas, D.; Spiller, S.; Moutinho, H.

2011-01-01

105

Results of Bayesian methods depend on details of implementation: An example of estimating salmon escapement goals  

USGS Publications Warehouse

Bayesian methods have been proposed to estimate optimal escapement goals, using both knowledge about physical determinants of salmon productivity and stock-recruitment data. The Bayesian approach has several advantages over many traditional methods for estimating stock productivity: it allows integration of information from diverse sources and provides a framework for decision-making that takes into account uncertainty reflected in the data. However, results can be critically dependent on details of implementation of this approach. For instance, unintended and unwarranted confidence about stock-recruitment relationships can arise if the range of relationships examined is too narrow, if too few discrete alternatives are considered, or if data are contradictory. This unfounded confidence can result in a suboptimal choice of a spawning escapement goal.

Adkison, M.D.; Peterman, R.M.

1996-01-01

106

Development of ultraviolet spectroscopic method for the estimation of metronidazole benzoate from pharmaceutical formulation  

PubMed Central

Background: The present study was undertaken with an objective to develop a simple, accurate, cost-effective and reproducible ultraviolet spectrophotometric method for the estimation of metronidazole benzoate (MB) from pharmaceutical formulations. Materials and Methods: The analysis was performed on ?max 268 nm by using 0.1 NHCl as diluents. The proposed method was validated on International Conference Harmonization guideline including the parameters viz., accuracy, linearity, precision, specificity and reproducibility. The proposed method was also used to access the content of MB in two commercial brands of Indian market. Results: Beer's law was obeyed in the concentration range of 1-10 ?g/ml having regression equation y = 0.078 x-0.012. The accuracy value for 4 ?g/ml and 5 ?g/ml concentration of MB was found to be 99.37% and 98.9% respectively. The relative standard deviation of interday and intraday was lesser than 1%. The developed method was applied on two different marketed brands and contents of MB were found to be 98.62% and 98.59% incompliance with labeled claim. The results were under the limit of acceptance statistically. Conclusion: It was concluded that the proposed method can be used for routine analysis of MB in bulk and commercial formulations. PMID:25097394

Mishra, Arun K.; Kumar, Arvind; Mishra, Amrita; Mishra, Hari V.

2014-01-01

107

A method of assessing the resilience of whole communities of children: An example from rural Australia  

PubMed Central

Background Children living in socioeconomic disadvantage are at risk of poor mental health outcomes. In order to focus and evaluate population health programs to facilitate children’s resilience, it is important to accurately assess baseline levels of functioning. With this end in mind, the aim of this study was to test the utility of 1) a voluntary random sampling method and 2) quantitative measures of adaptation (with national normative data) for assessing the resilience of children in an identified community. Method This cross-sectional study utilized a sample of participants (N?=?309), including parents (n?=?169), teachers (n?=?20) and children (n?=?170; age range?=?5-16 years), recruited from the schools in Tenterfield; a socioeconomically disadvantaged community in New South Wales, Australia. The Strengths and Difficulties Questionnaire (SDQ; including parent, teacher and youth versions) was used to measure psychological well-being and pro-social functioning, and NAPLAN results (individual children’s and whole school’s performance in literacy and numeracy) were used to measure level of academic achievement. Results The community’s disadvantage was evident in the whole school NAPLAN performance but not in the sample’s NAPLAN or SDQ results. The teacher SDQ ratings appeared to be more reliable than parent’s ratings. The voluntary random sampling method (requiring parental consent) led to sampling bias. Conclusions The key indicators of resilience - psychological well-being, pro-social functioning and academic achievement – can be measured in whole communities using the teacher version of the SDQ and whole school results on a national test of literacy and numeracy (e.g., Australia’s NAPLAN). A voluntary random sample (dependent upon parental consent) appears to have limited value due to the likelihood of sampling bias. PMID:22559152

2012-01-01

108

Pharmacokinetic study on the mechanism of interaction of sulfacetamide sodium with bovine serum albumin: a spectroscopic method.  

PubMed

The binding of sulfacetamide sodium (SAS) to bovine serum albumin (BSA) was investigated by spectroscopic methods, namely fluorescence, FT-IR and UV-vis absorption spectral studies. The binding parameters were evaluated by a fluorescence quenching method. The thermodynamic parameters, DeltaH(0), DeltaS(0)and DeltaG(0) were observed to be -49.03 k J mol(-1), -99.9 J K(-1) mol(-1) and -18.96 k J mol(-1), respectively. These indicated that the hydrogen bonding and weak van der Waals forces played major roles in the interaction. Based on Förster's theory of non-radiation energy transfer, the binding average distance, r, between the donor (BSA) and acceptor (SAS) was evaluated and found to be 3.72 nm. The spectral results showed that binding of SAS to BSA induced conformational changes in BSA. The effect of common ions and some of the polymers used in drug delivery for controlled release were also tested on the binding of SAS to BSA. PMID:20073032

Naik, Praveen N; Chimatadar, Shivamurti A; Nandibewoor, Sharanappa T

2010-03-01

109

Luminescent materials: probing the excited state of emission centers by spectroscopic methods  

NASA Astrophysics Data System (ADS)

We review recent methods employed to study the excited state of rare-earth centers in various luminescent and scintillating materials. The focus is on processes that help determine localization of the excited state within the material band gap, namely photoionization and thermally stimulated ionization. Then the tunneling process between the luminescence center and the trapping state is addressed. We describe the experimental implementation of methods recently developed to study these processes. We report theoretical models helping the data interpretation. We also present application to currently investigated materials.

Mihóková, E.; Nikl, M.

2015-01-01

110

Interactions between CdSe\\/CdS quantum dots and DNA through spectroscopic and electrochemical methods  

Microsoft Academic Search

The interaction of CdSe\\/CdS quantum dots (QDs) with Herring sperm-DNA (hs-DNA) has been studied by UV–vis spectroscopy and electrochemical method. Cu(phen)22+\\/1+ (phen=1, 10-phenanthroline) was used as an indicator for electroactive dsDNA or ssDNA. The apparent association constant has been deduced (4.94×103M?1 and 2.39×102M?1) from the absorption spectral changes of the dsDNA–QDs and ssDNA–QDs. The results of dissociation method suggest that

Qisui Wang; Lu Yang; Tingting Fang; Shuang Wu; Peng Liu; Xinmin Min; Xi Li

2011-01-01

111

Utilising a collective case study system theory mixed methods approach: a rural health example  

PubMed Central

Background Insight into local health service provision in rural communities is limited in the literature. The dominant workforce focus in the rural health literature, while revealing issues of shortage of maldistribution, does not describe service provision in rural towns. Similarly aggregation of data tends to render local health service provision virtually invisible. This paper describes a methodology to explore specific aspects of rural health service provision with an initial focus on understanding rurality as it pertains to rural physiotherapy service provision. Method A system theory-case study heuristic combined with a sequential mixed methods approach to provide a framework for both quantitative and qualitative exploration across sites. Stakeholder perspectives were obtained through surveys and in depth interviews. The investigation site was a large area of one Australian state with a mix of rural, regional and remote communities. Results 39 surveys were received from 11 locations within the investigation site and 19 in depth interviews were conducted. Stakeholder perspectives of rurality and workforce numbers informed the development of six case types relevant to the exploration of rural physiotherapy service provision. Participant perspective of rurality often differed with the geographical classification of their location. The numbers of onsite colleagues and local access to health services contributed to participant perceptions of rurality. Conclusions The complexity of understanding the concept of rurality was revealed by interview participants when providing their perspectives about rural physiotherapy service provision. Dual measures, such as rurality and workforce numbers, provide more relevant differentiation of sites to explore specific services, such rural physiotherapy service provision, than single measure of rurality as defined by geographic classification. The system theory-case study heuristic supports both qualitative and quantitative exploration in rural health services research. PMID:25066241

2014-01-01

112

High Resolution Seismic Imaging of Fault Zones: Methods and Examples From The San Andreas Fault  

NASA Astrophysics Data System (ADS)

Seismic imaging of fault zones at shallow depths is challenging. Conventional seismic reflection methods do not work well in fault zones that consist of non-planar strata or that have large variations in velocity structure, two properties that occur in most fault zones. Understanding the structure and geometry of fault zones is important to elucidate the earthquake hazard associated with fault zones and the barrier effect that faults impose on subsurface fluid flow. In collaboration with the San Francisco Public Utilities Commission (SFPUC) at San Andreas Lake on the San Francisco peninsula, we acquired combined seismic P-wave and S-wave reflection, refraction, and guided-wave data to image the principal strand of the San Andreas Fault (SAF) that ruptured the surface during the 1906 San Francisco earthquake and additional fault strands east of the rupture. The locations and geometries of these fault strands are important because the SFPUC is seismically retrofitting the Hetch Hetchy water delivery system, which provides much of the water for the San Francisco Bay area, and the delivery system is close to the SAF at San Andreas Lake. Seismic reflection images did not image the SAF zone well due to the brecciated bedrock, a lack of layered stratigraphy, and widely varying velocities. Tomographic P-wave velocity images clearly delineate the fault zone as a low-velocity zone at about 10 m depth in more competent rock, but due to soil saturation above the rock, the P-waves do not clearly image the fault strands at shallower depths. S-wave velocity images, however, clearly show a diagnostic low-velocity zone at the mapped 1906 surface break. To image the fault zone at greater depths, we utilized guided waves, which exhibit high amplitude seismic energy within fault zones. The guided waves appear to image the fault zone at varying depths depending on the frequency of the seismic waves. At higher frequencies (~30 to 40 Hz), the guided waves show strong amplification at the 1906 surface break and at about 20 m to the east, but at lower frequencies (2-5 Hz), the guided waves show strong amplification approximately 10 m east of the 1906 surface break. We attribute the difference in amplification of guided waves to an east-dipping fault strand that merges with other strands below about 10 m depth. Vp/Vs and Poisson's ratios clearly delineate multiple fault strands about 2 km north of the mapped 1906 surface break at the SFPUC intake structure. Combining these fault-imaging methods provide a powerful set of tools for mapping fault zones in the shallow subsurface in areas of complex geology.

Catchings, R. D.; Rymer, M. J.; Goldman, M.; Prentice, C. S.; Sickler, R. R.; Criley, C.

2011-12-01

113

Problems in estimating self-supplied industrial water use by indirect methods, the California example  

USGS Publications Warehouse

Consumptive fresh-water use by industry in California is estimated at about 230 million gallons per day, or about one-half of one percent of agricultural withdrawals in the State , and only about 1 percent of agricultural consumptive use. Therefore, a significant State-wide realignment of the total water resources could not be made by industrial conservation measures. Nevertheless, considerable latitude for water conservation exists in industry -- fresh water consumed by self-supplied industry amounts to about 40 percent of its withdrawals in California, and only about 10 to 15 percent nationally (not including power-plant use). Furthermore, where firms withdraw and consume less water there is more for others nearby to use. The main question in attempting to estimate self-supplied industrial water use in California by indirect methods was whether accurate estimates of industrial water use could be made from data on surrogates such as production and employment. The answer is apparently not. A fundamental problem was that different data bases produced variable coefficients of water use for similar industries. Much of the potential for error appeared to lie in the water data bases rather than the production or employment data. The apparent reasons are that water-use data are based on responses to questionnaires, which are prone to errors in reporting, and because the data may be aggregated inappropriately for this kind of correlation. Industries within an apparently similar category commonly use different amounts of water, both because of differences in the product and because of differences in production processes even where the end-product is similar. (USGS)

Burt, R.J.

1983-01-01

114

Quantification of sediment supply : a method and an example from Triassic of Western European basins  

NASA Astrophysics Data System (ADS)

Triassic is a key period of Earth history, with tectonic, climatic and eustatic events. It corresponds to (i) the initial fragmentation of the Pangea, (ii) a transition from Paleozoic ice house to Mesozoic green house, (iii) a sea-level rise from Upper Triassic, followed by an eustatic fall during Lias. This special geological setting has led to the formation of large Mesozoic basins, mainly characterized by a continental sedimentation, with fluvial and/or evaporitic environments, well-conserved in Pangean supercontinent. This Triassic specificity implies a total free space for sedimentation, i.e. accommodation (A), balanced with an important sediment supply (S), as SgeA.The purpose of this study is to develop a good methodology for understanding the S parameter in past geological systems, as Triassic. Firstly, by considering three key periods of Triassic : (1) the Lower Scythian, (2) the Lower Ladinian, (3) the Carnian-Norien ; we have realized paleogeographic and paleotopographic maps either for Western Europe or entire world. These reconstructions allow us to precise (i) erosional or sedimentary areas, (ii) coastal lines and sebkha boundaries, (iii) river basins and continental systems associated. Moreover, by using an atmospheric general circulation model (AGCM), we are actually simulating the climatic response by applying data of maps for Triassic European areas. By this way, we are able to obtain different parameters of climate (rainfall, temperature variations,...) in order to test the effect on topography, evaporitic plains and climate interactions. In parallel, paleoenvironmental maps allow us to separate three main fluvial systems developed during the Triassic period : (1) larged braided alluvial systems in vast endoreic basins that characterize the transitional stage between the Zeichstein system (Permian) and the Tethyan system (Triassic) ; (2) anastomosed systems whose preservation is controlled by sea-level (Anisian and Middle Carnian) ; (3) alluvial fans/lacustrine mixed systems, whose base-level is locally controlled by a lake but topography and local tectonic play a major role in the formation of these systems (Norian). A SW-NE transect and lithologies surimposed on isopach maps are also realized for the Buntsandstein (Scythian to Lower Anisian), from the Paris Basin to North Sea, via German Basin. It allows us to realize (i) high-resolution sequence stratigraphy correlations with surimposed paleoenvironements, and (ii) a quantification of siliciclastic volumes (sand/shale) for each stratigraphic interval. This integrated method has for ultimate question to understand the role of sediments supplies (S parameter) in stratigraphic architecture acquisition and fluviatil systems evolution.

Peron, S.; Bourquin, S.; Duran, M.; Fluteau, F.; Guillocheau, F.

2003-04-01

115

Identification of pyrazosulfuron-ethyl binding affinity and binding site subdomain IIA in human serum albumin by spectroscopic methods  

NASA Astrophysics Data System (ADS)

Pyrazosulfuron-ethyl (PY) is a sulfonylurea herbicide developed by DuPont which has been widely used for weed control in cereals. The determination of PY binding affinity and binding site in human serum albumin (HSA) by spectroscopic methods is the subject of this work. From the fluorescence emission, circular dichroism and three-dimensional fluorescence results, the interaction of PY with HSA caused secondary structure changes in the protein. Fluorescence data demonstrated that the quenching of HSA fluorescence by PY was the result of the formation of HSA-PY complex at 1:1 molar ratio, a static mechanism was confirmed to lead to the fluorescence quenching. Hydrophobic probe 8-anilino-1-naphthalenesulfonic acid (ANS) displacement results show that hydrophobic patches are the major sites for PY binding on HSA. The thermodynamic parameters ? H° and ? S° were calculated to be -36.32 kJ mol -1 and -35.91 J mol -1 K -1, which illustrated van der Waals forces and hydrogen bonds interactions were the dominant intermolecular force in stabilizing the complex. Also, site marker competitive experiments showed that the binding of PY to HSA took place primarily in subdomain IIA (Sudlow's site I). What presented in this paper binding research enriches our knowledge of the interaction between sulfonylurea herbicides and the physiologically important protein HSA.

Ding, Fei; Liu, Wei; Zhang, Xi; Wu, Li-Jun; Zhang, Li; Sun, Ying

2010-03-01

116

Interaction between deferiprone and human serum albumin: multi-spectroscopic, electrochemical and molecular docking methods.  

PubMed

The interactions between deferiprone (DEP) and human serum albumin (HSA) have been investigated systematically by fluorescence, Circular dichroism (CD) spectroscopy, UV-Vis absorption spectroscopy, electrochemistry and molecular modeling methods. The fluorescence quenching observed is attributed to the formation of a complex between HSA and DEP, and the reverse temperature effect of the fluorescence quenching has been found and discussed. The thermodynamic parameters, enthalpy changes (?H) and entropy change (?S) were calculated, according to the Van't Hoff equation. These data suggested that hydrophobic interaction was the predominant intermolecular forces stabilizing the complex, which was in good agreement with the results of molecular modeling study. The primary binding pattern is determined by hydrophobic interaction occurring in Sudlow's site I of HSA. DEP could slightly change the secondary structure and induce unfolding of the polypeptides of protein. An average binding distance of ?2.88 nm has been determined on the basis of the Förster's resonance energy theory (FRET). PMID:25159837

Seyed Dorraji, M S; Panahi Azar, V; Rasoulifard, M H

2014-11-20

117

Characterization of organic and inorganic optoelectronic semiconductor devices using advanced spectroscopic methods  

NASA Astrophysics Data System (ADS)

In this thesis, advanced spectroscopy methods are discussed and applied to gain understanding of the physical properties of organic conjugated molecules, II-VI thin film semiconductors, and vertical cavity surface emitting lasers (VCSEL). Experiments include single photon and two-photon excitation with lasers, with subsequent measurements of the absorption and photoluminescence, as well as photocurrent measurements using tungsten and xenon lamps, measuring the direct current and the alternating current of the devices. The materials are investigated in dissolved form (conjugated polymers), thin films (polymers, II-VI semiconductors), and complex layer structures (hybrid device, VCSEL). The experiments are analyzed and interpreted by newly developed or applied theories for two-photon saturation processes in semiconductors, bandgap shrinkage due to optically induced electron hole pairs, and the principle of detailed balance to describe the photoluminescence in thin film cadmium sulfide.

Schroeder, Raoul

118

Characterization of the Interaction between Eupatorin and Bovine Serum Albumin by Spectroscopic and Molecular Modeling Methods  

PubMed Central

This study investigated the interaction between eupatorin and bovine serum albumin (BSA) using ultraviolet-visible (UV-vis) absorption, fluorescence, synchronous fluorescence, circular dichroism (CD) spectroscopies, and molecular modeling at pH 7.4. Results of UV-vis and fluorescence spectroscopies illustrated that BSA fluorescence was quenched by eupatorin via a static quenching mechanism. Thermodynamic parameters revealed that hydrophobic and electrostatic interactions played major roles in the interaction. Moreover, the efficiency of energy transfer, and the distance between BSA and acceptor eupatorin, were calculated. The effects of eupatorin on the BSA conformation were analyzed using UV-vis, CD, and synchronous fluorescence. Finally, the binding of eupatorin to BSA was modeled using the molecular docking method. PMID:23839090

Xu, Hongliang; Yao, Nannan; Xu, Haoran; Wang, Tianshi; Li, Guiying; Li, Zhengqiang

2013-01-01

119

Characterization of the Interaction between Eupatorin and Bovine Serum Albumin by Spectroscopic and Molecular Modeling Methods.  

PubMed

This study investigated the interaction between eupatorin and bovine serum albumin (BSA) using ultraviolet-visible (UV-vis) absorption, fluorescence, synchronous fluorescence, circular dichroism (CD) spectroscopies, and molecular modeling at pH 7.4. Results of UV-vis and fluorescence spectroscopies illustrated that BSA fluorescence was quenched by eupatorin via a static quenching mechanism. Thermodynamic parameters revealed that hydrophobic and electrostatic interactions played major roles in the interaction. Moreover, the efficiency of energy transfer, and the distance between BSA and acceptor eupatorin, were calculated. The effects of eupatorin on the BSA conformation were analyzed using UV-vis, CD, and synchronous fluorescence. Finally, the binding of eupatorin to BSA was modeled using the molecular docking method. PMID:23839090

Xu, Hongliang; Yao, Nannan; Xu, Haoran; Wang, Tianshi; Li, Guiying; Li, Zhengqiang

2013-01-01

120

Standard test method for nondestructive assay of special nuclear material holdup using Gamma-Ray spectroscopic methods  

E-print Network

1.1 This test method describes gamma-ray methods used to nondestructively measure the quantity of 235U, or 239Pu remaining as holdup in nuclear facilities. Holdup occurs in all facilities where nuclear material is processed, in process equipment, in exhaust ventilation systems and in building walls and floors. 1.2 This test method includes information useful for management, planning, selection of equipment, consideration of interferences, measurement program definition, and the utilization of resources (1, 2, 3, 4). 1.3 The measurement of nuclear material hold up in process equipment requires a scientific knowledge of radiation sources and detectors, transmission of radiation, calibration, facility operations and error analysis. It is subject to the constraints of the facility, management, budget, and schedule; plus health and safety requirements; as well as the laws of physics. The measurement process includes defining measurement uncertainties and is sensitive to the form and distribution of the material...

American Society for Testing and Materials. Philadelphia

2007-01-01

121

EDITORIAL: Spectroscopic diagnostics of magnetic fusion plasmas Spectroscopic diagnostics of magnetic fusion plasmas  

NASA Astrophysics Data System (ADS)

Spectroscopy has always been an integral part of the diagnostic systems of super-hot fusion plasmas. The numerous results derived from studies of the emitted spectra have been highly important for elucidating key physical properties of fusion plasmas; moreover, plasma spectroscopy has provided crucial input for development of new tokamaks, stellarators and other advanced devices. Many concepts of spectroscopic diagnostics in magnetic confinement fusion (MCF) are well established and have been thoroughly tested over decades. However the recent advances on the existing machines (e.g. JET, ASDEX Upgrade and LHD), linked to the accelerating development of the international ITER project, call for new and improved spectroscopic methods. These are required to determine the key plasma parameters in all regions of the plasma volume while coping with complex materials, new advanced operating scenarios and a hostile radiation environment. It is such advanced methods and techniques that are the focus of this special issue. The papers collected here provide an extensive representation of the state of the art in spectroscopic diagnostics of MCF plasmas. On the experimental side, several contributions from the existing tokamaks and stellarators demonstrate how sophisticated spectroscopic methods are used to derive information on temporal evolution of electron temperature and density, particle velocity in peripheral plasmas, edge ion temperature, and many other quantities of interest. A group of papers addresses development of new experimental techniques for future measurements, including specific spectroscopic tools for ITER diagnostics. As accurate atomic data are at the cornerstone of reliable diagnostics, several papers describe newly calculated spectroscopic and collisional data for species and processes of highest importance in fusion devices, such as, for example, charge exchange for neutral beam injection diagnostics. Finally, a group of contributions address various issues related to theoretical modelling of plasma emission spectra including collisional-radiative simulations and line profile modelling. We hope that the papers contributed to this special issue will serve as a valuable resource for the MCF community.

Neu, Rudolf; Summers, Hugh P.; Ralchenko, Yuri

2010-07-01

122

Insights into in vitro binding of parecoxib to human serum albumin by spectroscopic methods.  

PubMed

Herein, we report the effect of parecoxib on the structure and function of human serum albumin (HSA) by using fluorescence, circular dichroism (CD), Fourier transforms infrared (FTIR), three-dimensional (3D) fluorescence spectroscopy, and molecular docking techniques. The Stern-Volmer quenching constants K(SV) and the corresponding thermodynamic parameters ?H, ?G, and ?S have been estimated by the fluorescence quenching method. The results indicated that parecoxib binds spontaneously with HSA through van der Waals forces and hydrogen bonds with binding constant of 3.45 × 10(4) M(-1) at 298 K. It can be seen from far-UV CD spectra that the ?-helical network of HSA is disrupted and its content decreases from 60.5% to 49.6% at drug:protein = 10:1. Protein tertiary structural alterations induced by parecoxib were also confirmed by FTIR and 3D fluorescence spectroscopy. The molecular docking study indicated that parecoxib is embedded into the hydrophobic pocket of HSA. PMID:24939449

Shang, Shujun; Liu, Qingling; Gao, Jiandong; Zhu, Yulin; Liu, Jingying; Wang, Kaiyan; Shao, Wei; Zhang, Shudong

2014-10-01

123

Chemometric optimization of the robustness of the near infrared spectroscopic method in wheat quality control.  

PubMed

A chemometric approach was applied for the optimization of the robustness of the NIRS method for wheat quality control. Due to the high number of experimental (n=6) and response variables to be studied (n=7) the optimization experiment was divided into two stages: screening stage in order to evaluate which of the considered variables were significant, and optimization stage to optimize the identified factors in the previously selected experimental domain. The significant variables were identified by using fractional factorial experimental design, whilst Box-Wilson rotatable central composite design (CCRD) was run to obtain the optimal values for the significant variables. The measured responses included: moisture, protein and wet gluten content, Zeleny sedimentation value and deformation energy. In order to achieve the minimal variation in responses, the optimal factor settings were found by minimizing the propagation of error (POE). The simultaneous optimization of factors was conducted by desirability function. The highest desirability of 87.63% was accomplished by setting up experimental conditions as follows: 19.9°C for sample temperature, 19.3°C for ambient temperature and 240V for instrument voltage. PMID:25281098

Poji?, Milica; Raki?, Dušan; Lazi?, Zivorad

2015-01-01

124

Vibrational spectroscopic study and NBO analysis on tranexamic acid using DFT method.  

PubMed

In this work, we reported the vibrational spectra of tranexamic acid (TA) by experimental and quantum chemical calculation. The solid phase FT-Raman and FT-IR spectra of the title compound were recorded in the region 4000 cm(-1) to 100 cm(-1) and 4000 cm(-1) to 400 cm(-1) respectively. The molecular geometry, harmonic vibrational frequencies and bonding features of TA in the ground state have been calculated by using density functional theory (DFT) B3LYP method with standard 6-31G(d,p) basis set. The scaled theoretical wavenumber showed very good agreement with the experimental values. The vibrational assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes. Stability of the molecule, arising from hyperconjugative interactions and charge delocalization, has been analyzed using Natural Bond Orbital (NBO) analysis. The results show that ED in the ?(*) and ?(*) antibonding orbitals and second order delocalization energies E(2) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. The electrostatic potential mapped onto an isodensity surface has been obtained. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The thermodynamic properties (heat capacity, entropy, and enthalpy) of the title compound at different temperatures were calculated in gas phase. PMID:24747330

Muthu, S; Prabhakaran, A

2014-08-14

125

Vibrational spectroscopic study and NBO analysis on tranexamic acid using DFT method  

NASA Astrophysics Data System (ADS)

In this work, we reported the vibrational spectra of tranexamic acid (TA) by experimental and quantum chemical calculation. The solid phase FT-Raman and FT-IR spectra of the title compound were recorded in the region 4000 cm-1 to 100 cm-1 and 4000 cm-1 to 400 cm-1 respectively. The molecular geometry, harmonic vibrational frequencies and bonding features of TA in the ground state have been calculated by using density functional theory (DFT) B3LYP method with standard 6-31G(d,p) basis set. The scaled theoretical wavenumber showed very good agreement with the experimental values. The vibrational assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes. Stability of the molecule, arising from hyperconjugative interactions and charge delocalization, has been analyzed using Natural Bond Orbital (NBO) analysis. The results show that ED in the ?* and ?* antibonding orbitals and second order delocalization energies E(2) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. The electrostatic potential mapped onto an isodensity surface has been obtained. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The thermodynamic properties (heat capacity, entropy, and enthalpy) of the title compound at different temperatures were calculated in gas phase.

Muthu, S.; Prabhakaran, A.

2014-08-01

126

Interaction of one anthraquinone derivative with ctDNA analyzed by spectroscopic and modeling methods.  

PubMed

The interaction of one anthraquinone derivative (AOMan) with calf thymus deoxyribonucleic acid (ctDNA) was systematically investigated at physiological pH 7.4 by fluorescence spectroscopy and molecular modeling. Binding constants of ctDNA with AOMan were calculated at different temperatures. Thermodynamic parameters, enthalpy and entropy changes were calculated according to Van't Hoff equation, which indicated that the reaction was spontaneous and predominantly enthalpically driven. The increasing viscosity of ctDNA indicated that AOMan could intercalate into the base pairs of ctDNA. This conclusion was also demonstrated by the results obtained from KI quenching, denatured DNA studies and fluorescence polarization experiment. Furthermore, the molecular modeling results showed that anthraquinone ring tended to slide into the G-C rich region of ctDNA through the hydrogen bond, which are consistent with the results from experimental methods. Studying the binding interaction of target anthraquinones with DNA is one of the key steps in their DNA-changing action and the design of new drugs. PMID:24957254

Cui, Yanrui; Fu, Zheng; Geng, Shaoguang; Zhang, Guisheng; Cui, Fengling

2014-09-01

127

Investigation on interaction between Ligupurpuroside A and pepsin by spectroscopic and docking methods  

NASA Astrophysics Data System (ADS)

Ligupurpuroside A is one of the major glycoside in Ku-Din-Cha, a type of Chinese functional tea. In order to better understand its digestion and metabolism in humans, the interaction between Ligupurpuroside A and pepsin has been investigated by fluorescence spectra, UV-vis absorption spectra and synchronous fluorescence spectra along with molecular docking method. The fluorescence experiments indicate that Ligupurpuroside A can effectively quench the intrinsic fluorescence of pepsin through a combined quenching way at the low concentration of Ligupurpuroside A, and a static quenching procedure at the high concentration. The binding constant, binding sites of Ligupurpuroside A with pepsin have been calculated. The thermodynamic analysis suggests that non-covalent reactions, including electrostatic force, hydrophobic interaction and hydrogen bond are the main forces stabilizing the complex. According to the Förster's non-radiation energy transfer theory, the binding distance between pepsin and Ligupurpuroside A was calculated to be 3.15 nm, which implies that energy transfer occurs between pepsin and Ligupurpuroside A. Conformation change of pepsin was observed from UV-vis absorption spectra and synchronous fluorescence spectra under experimental conditions. In addition, all these experimental results have been validated by the protein-ligand docking studies which show that Ligupurpuroside A is located in the cleft between the domains of pepsin.

Shen, Liangliang; Xu, Hong; Huang, Fengwen; Li, Yi; Xiao, Huafeng; Yang, Zhen; Hu, Zhangli; He, Zhendan; Zeng, Zheling; Li, Yinong

2015-01-01

128

Intermolecular interaction of prednisolone with bovine serum albumin: spectroscopic and molecular docking methods.  

PubMed

The intermolecular interaction of prednisolone with bovine serum albumin (BSA) was studied using fluorescence, circular dichroism (CD) and molecular docking methods. The experimental results showed that the fluorescence quenching of the BSA at 338 nm by prednisolone resulted from the formation of prednisolone-BSA complex. The number of binding sites (n) for prednisolone binding on BSA was approximately equal to 1. Base on the sign and magnitude of the enthalpy and entropy changes (?H(0)=-149.6 kJ mol(-1) and ?S(0)=-370.7 J mol(-1)K(-1)) and the results of molecular docking, it could be suggested that the interaction forces were mainly Van der Waals and hydrogen bonding interactions. Moreover, in the binding process of BSA with prednisolone, prednisolone molecule can be inserted into the hydrophobic cavity of subdomain IIIA (site II) of BSA. The distance between prednisolone and Trp residue of BSA was calculated as 2.264 nm according to Forster's non-radiative energy transfer theory. PMID:23261625

Shi, Jie-hua; Zhu, Ying-Yao; Wang, Jing; Chen, Jun; Shen, Ya-Jing

2013-02-15

129

Investigation on interaction between Ligupurpuroside A and pepsin by spectroscopic and docking methods.  

PubMed

Ligupurpuroside A is one of the major glycoside in Ku-Din-Cha, a type of Chinese functional tea. In order to better understand its digestion and metabolism in humans, the interaction between Ligupurpuroside A and pepsin has been investigated by fluorescence spectra, UV-vis absorption spectra and synchronous fluorescence spectra along with molecular docking method. The fluorescence experiments indicate that Ligupurpuroside A can effectively quench the intrinsic fluorescence of pepsin through a combined quenching way at the low concentration of Ligupurpuroside A, and a static quenching procedure at the high concentration. The binding constant, binding sites of Ligupurpuroside A with pepsin have been calculated. The thermodynamic analysis suggests that non-covalent reactions, including electrostatic force, hydrophobic interaction and hydrogen bond are the main forces stabilizing the complex. According to the Förster's non-radiation energy transfer theory, the binding distance between pepsin and Ligupurpuroside A was calculated to be 3.15 nm, which implies that energy transfer occurs between pepsin and Ligupurpuroside A. Conformation change of pepsin was observed from UV-vis absorption spectra and synchronous fluorescence spectra under experimental conditions. In addition, all these experimental results have been validated by the protein-ligand docking studies which show that Ligupurpuroside A is located in the cleft between the domains of pepsin. PMID:25078459

Shen, Liangliang; Xu, Hong; Huang, Fengwen; Li, Yi; Xiao, Huafeng; Yang, Zhen; Hu, Zhangli; He, Zhendan; Zeng, Zheling; Li, Yinong

2015-01-25

130

IR spectroscopic methods for the investigation of the CO release from CORMs.  

PubMed

Carbon monoxide (CO) is a toxic gas for mammals, and despite this fact, it is naturally produced in these organisms and has been proven to be beneficial in medical treatments, too. Therefore, CO-releasing molecules (CORMs) are intensively developed to administer and dose CO for physiological applications. Nearly all of these compounds are metal carbonyl complexes, which have been synthesized and investigated. However, for most of these CORMs, the exact reaction mechanisms of CO release is not completely elucidated, although it is of utmost importance. The widely used myoglobin assay for testing the CO release has several disadvantages, and therefore, different methods have to be applied to characterize CORMs. In this work, different setups of IR absorption spectroscopy are used to analyze and quantify the CO release during the decay of various CORMs: IR spectroscopy of the gas phase is applied to follow the CO liberation, and attenuated total reflection (ATR) IR spectroscopy is used to record the decay of the metal carbonyl. IR spectroscopy supported by DFT calculations yields valuable insights in the CO release reaction mechanism. The focus is set on two different CORMs: CORM-2 (Ru2(CO)(6)Cl(4)) and on the photoactive CORM-S1 (photoCORM [Fe(CO)2(SCH2CH2NH2)2]). Our results indicate that the CO liberation from CORM-2 strongly depends on sodium dithionite, which is required for the commonly applied myoglobin assay and that CORM-S1 loses all its bound CO molecules upon irradiation with blue light. PMID:24978105

Klein, Moritz; Neugebauer, Ute; Gheisari, Ali; Malassa, Astrid; Jazzazi, Taghreed M A; Froehlich, Frank; Westerhausen, Matthias; Schmitt, Michael; Popp, Jürgen

2014-07-24

131

Development of a Tunable Laser Spectroscopic Method for Determining Multiple Sulfur Isotope Composition of Nanomoles of SO2  

NASA Astrophysics Data System (ADS)

Multiple sulfur isotope (32S, 33S, 34S, 36S) analyses of geological material provide important constraints on the sulfur cycles on Earth [1] and other planetary bodies, e.g., Mars [2]. However, most current multiple sulfur isotope measurements are performed on magnetic sector isotope ratio mass spectrometers (IRMS) and thus require relatively large sample size (usually about several micromoles of sulfur, except the MC-ICPMS and SIMS methods) and time-consuming sample preparation procedures. More importantly, these IRMS methods demand relatively sophisticated instrumentation, and are not ideal for field measurements or flight missions. In contrast, laser spectroscopic methods provide opportunities for significantly reducing the sample size requirement and enabling real-time monitoring in the field, and have been proven to be of great importance in the isotopic measurements of many molecules in nature, e.g. CO2, H2O, N2O, CH4. Based on a prototype built for measuring ?34S of SO2 [3], we're developing a new tunable laser spectrometer (TLS) for simultaneously determining the ?34S and ?33S of nanomoles of pure SO2. We have identified a new spectral window (<1 cm-1 wide) suitable for measuring 32SO2, 33SO2, 34SO2 simultaneously. Ongoing work focuses on increasing the optical path length of the analysis cell and determining the optimal analytical conditions, with the goal of achieving ?0.5‰ precision in both ?34S and ?33S over 30 seconds of analysis duration of ~20 nmol of pure SO2. Progress of these developments and comparison with conventional IRMS methods will be presented at the meeting. As a case study, we will also present preliminary TLS results from laboratory low pressure SO2 UV photolysis experiments where ?34S and ?33S of the residual SO2 are expected to decrease as the photolysis proceeds [4]. Future developments of this method will involve the coupling of a sample introduction system to enable multiple sulfur isotope analysis of samples other than pure SO2 [3]. [1] Johnston (2011) Earth Sci. Rev. 106, 161-183; [2] Farquhar et al. (2000) Nature. 404, 50-52; [3] Christensen et al. (2007) Anal. Chem. 79, 9261-9268; [4] Guo et al. (2010) Geochim. Cosmochim. Acta. 74, A366.

Guo, W.; Christensen, L. E.

2013-12-01

132

Determination of the structure of the oxidative cyclization products of 4-methoxy-N, N'-dithioaroyl- m-phenylendiamines by spectroscopic methods  

NASA Astrophysics Data System (ADS)

4-Methoxy-N, N'-dithiobenzoyl- m-phenylendiamine (dithioamide) has been subjected to oxidation with potassium ferricyanide. By using the equimolar amounts of dithioamide and ferricyanide only a partially cylized compounds has been obtained, whereas when the great amount of ferricyanide is used the cyclization is completed. The structures of the oxidative products as well as of the parent compounds are studied by spectroscopic methods.

Petrova, D.; Kostov, V.; Petrov, I.

1986-03-01

133

Characterization of novel lithium battery cathode materials by spectroscopic methods: the Li5+xFeO? system.  

PubMed

The novel, lithium-rich oxide-phase Li?FeO? (LFO) could, in theory, deliver a specific capacity >900 mAh/g when deployed as a cathode or cathode precursor in a battery with a lithium-based anode. However, research results to date on LFO indicate that less than one of the five Li? cations can be reversibly de-intercalated/re-intercalated during repetitive charging and discharging cycles. In the present research, the system Li5+xFeO? with x values in the range of 0.0-2.0 was investigated by a combination of Raman and X-ray absorption spectroscopic methods supported by X-ray diffraction (XRD) analysis in order to determine if the Li?FeO? lattice would accommodate additional Li? ions, with concomitant lowering of the valence on the FeIII cations. Both the Raman phonon spectra and the XRD patterns were invariant for all values of x, strongly indicating that additional Li? did not enter the Li?FeO? lattice. Also, Raman spectral results and high-resolution synchrotron XRD data revealed the presence of second-phase Li?O in all samples with x greater than 0.0. Synchrotron X-ray absorption spectroscopy at the Fe k? edge performed on the sample with a Li-Fe ratio of 7.0 (i.e., x = 2.0) showed no evidence for the presence of FeII. This resistance to accepting more lithium into the Li?FeO? structure is attributed to the exceedingly stable nature of high-spin FeIII in tetrahedral "FeIIIO?" structural units of Li?FeO?. Partial substitution of the FeIII with other cations could provide a path toward increasing the reversible Li? content of Li5xFeO?-type phases. PMID:23876729

Maroni, Victor A; Johnson, Christopher S; Rood, Shawn C M; Kropf, A Jeremy; Bass, Dean A

2013-08-01

134

Study on the interaction of Co (III) DiAmsar with serum albumins: Spectroscopic and molecular docking methods  

NASA Astrophysics Data System (ADS)

This study was designed to examine the interaction of cobalt-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1,8-diamine (Co(III) DiAmsar) as a hexadentate ligand with human serum albumin (HSA) and bovine serum albumin (BSA) under physiological conditions in Tris-HCl buffer solution at pH 7.4. To this aim, at first, Co (III) DiAmsar was synthesized and characterized by nuclear magnetic resonance (NMR), and mass spectroscopy and then its interaction with HSA and BSA was investigated by means of various spectroscopic methods (Fourier transform infrared (FT-IR), UV-visible (UV-vis), fluorescence, and cyclic voltammetry (CV)) and molecular docking technique. The results of fluorescence titration revealed that the Co (III) DiAmsar strongly quench the intrinsic fluorescence of HSA and BSA through a static quenching procedure. Binding constants (Ka) and the number of binding sites (n ? 1) were calculated using Stern-Volmer equations. The ?G parameters at different temperatures were calculated. Subsequently, the values of ?H and ?S were also calculated, which revealed that the van der Waals and hydrogen bonding interaction splay a major role in Co (III) DiAmsar-HSA and Co (III) DiAmsar-BSA associations. The distance r between donor (HSA and BSA) and acceptor (Co (III) DiAmsar) was obtained according to fluorescence resonance energy transfer. The data obtained by the molecular modeling study revealed the surrounding residues of HSA and BSA around Co (III) DiAmsar.

Farahani, Bahman Vasheghani; Bardajee, Ghasem Rezanejade; Rajabi, Farzaneh Hosseinpour; Hooshyar, Zari

2015-01-01

135

Studies of the interaction between demeclocycline and human serum albumin by multi-spectroscopic and molecular docking methods.  

PubMed

This study was designed to examine the interaction of demeclocycline (DMCTC) with human serum albumin (HSA) by multi-spectroscopic and molecular docking methods. The inner filter effect was corrected before we calculated the binding parameters. Fluorescence and UV-vis spectroscopy revealed that DMCTC induced the fluorescence quenching of HSA though a static quenching procedure. Thermodynamic analysis by Van Hoff equation found enthalpy change (?H) and entropy change (?S) were -53.01 kJ mol(-1) and -65.13 J mol(-1)K(-1), respectively, which indicated hydrogen bond and van der Waals force were the predominant force in the binding process. According to fluorescence resonance energy transfer (FRET), the specific binding distances between Trp-214 (donor) and DMCTC (acceptor) were 3.18 nm. Through site marker competitive experiments, subdomain IIA of HSA has been assigned to possess the high-affinity binding site of DMCTC. The three dimensional fluorescence showed that the conformation of HSA was changed after its complexation with DMCTC, and the alternations of protein secondary structure were quantitatively calculated from FT-IR with reduction of ?-helices content about 4.8%, ?-sheet from 30.3% to 21.6% and with increases of ?-turn from 15.6% to 22.2%. Furthermore, the binding details between DMCTC and HSA were further confirmed by molecular docking studies, which revealed that DMCTC was bound at subdomain IIA through multiple interactions, such as hydrophobic effect, polar forces and ?-? interactions. Moreover, the coexist metal ions such as Al(3+), Fe(3+), Cu(2+), Cr(3+) and Cd(2+) can decrease the binding constants of DMCTC-HSA. PMID:23261611

Dong, Chengyu; Ma, Shuying; Liu, Ying

2013-02-15

136

Study on the interaction of Co (III) DiAmsar with serum albumins: spectroscopic and molecular docking methods.  

PubMed

This study was designed to examine the interaction of cobalt-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1,8-diamine (Co(III) DiAmsar) as a hexadentate ligand with human serum albumin (HSA) and bovine serum albumin (BSA) under physiological conditions in Tris-HCl buffer solution at pH 7.4. To this aim, at first, Co (III) DiAmsar was synthesized and characterized by nuclear magnetic resonance (NMR), and mass spectroscopy and then its interaction with HSA and BSA was investigated by means of various spectroscopic methods (Fourier transform infrared (FT-IR), UV-visible (UV-vis), fluorescence, and cyclic voltammetry (CV)) and molecular docking technique. The results of fluorescence titration revealed that the Co (III) DiAmsar strongly quench the intrinsic fluorescence of HSA and BSA through a static quenching procedure. Binding constants (Ka) and the number of binding sites (n?1) were calculated using Stern-Volmer equations. The ?G parameters at different temperatures were calculated. Subsequently, the values of ?H and ?S were also calculated, which revealed that the van der Waals and hydrogen bonding interaction splay a major role in Co (III) DiAmsar-HSA and Co (III) DiAmsar-BSA associations. The distance r between donor (HSA and BSA) and acceptor (Co (III) DiAmsar) was obtained according to fluorescence resonance energy transfer. The data obtained by the molecular modeling study revealed the surrounding residues of HSA and BSA around Co (III) DiAmsar. PMID:25105263

Farahani, Bahman Vasheghani; Bardajee, Ghasem Rezanejade; Rajabi, Farzaneh Hosseinpour; Hooshyar, Zari

2015-01-25

137

Near-infrared diode laser based spectroscopic detection of ammonia: a comparative study of photoacoustic and direct optical absorption methods  

NASA Technical Reports Server (NTRS)

A photoacoustic spectroscopic (PAS) and a direct optical absorption spectroscopic (OAS) gas sensor, both using continuous-wave room-temperature diode lasers operating at 1531.8 nm, were compared on the basis of ammonia detection. Excellent linear correlation between the detector signals of the two systems was found. Although the physical properties and the mode of operation of both sensors were significantly different, their performances were found to be remarkably similar, with a sub-ppm level minimum detectable concentration of ammonia and a fast response time in the range of a few minutes.

Bozoki, Zoltan; Mohacsi, Arpad; Szabo, Gabor; Bor, Zsolt; Erdelyi, Miklos; Chen, Weidong; Tittel, Frank K.

2002-01-01

138

Recent advances in time-frequency analysis methods for machinery fault diagnosis: A review with application examples  

NASA Astrophysics Data System (ADS)

Nonstationary signal analysis is one of the main topics in the field of machinery fault diagnosis. Time-frequency analysis can identify the signal frequency components, reveals their time variant features, and is an effective tool to extract machinery health information contained in nonstationary signals. Various time-frequency analysis methods have been proposed and applied to machinery fault diagnosis. These include linear and bilinear time-frequency representations (e.g., wavelet transform, Cohen and affine class distributions), adaptive parametric time-frequency analysis (based on atomic decomposition and time-frequency auto-regressive moving average models), adaptive non-parametric time-frequency analysis (e.g., Hilbert-Huang transform, local mean decomposition, and energy separation), and time varying higher order spectra. This paper presents a systematic review of over 20 major such methods reported in more than 100 representative articles published since 1990. Their fundamental principles, advantages and disadvantages, and applications to fault diagnosis of machinery have been examined. Some examples have also been provided to illustrate their performance.

Feng, Zhipeng; Liang, Ming; Chu, Fulei

2013-07-01

139

CD Spectroscope  

NSDL National Science Digital Library

In this activity, learners use an old CD to construct a spectroscope, a device that separates light into its component colors. Learners will hold it up to various light sources to examine how different light has different color strengths. Use this activity to introduce learners to the color spectrum and the tools scientists use to study it.

University, Colorado S.

2009-01-01

140

Spectroscopic Diagnostics for AGNs  

E-print Network

A review of the spectroscopic tools needed to characterize AGNs is presented. This review focusses on ultraviolet, optical and infrared emission-line diagnostics specifically designed to help differentiate AGNs from starburst-dominated galaxies. The strengths and weaknesses of these methods are discussed in the context of on-going and future AGN surveys.

Sylvain Veilleux

2002-01-08

141

Disjunctive Kriging: 2. Examples  

Microsoft Academic Search

The disjunctive kriging (DK) method described in detail in the previous paper of this series is illustrated by two examples. The first example is for the electrical conductivity (EC) which is approximately lognormally distributed. In the second example the natural logarithm of the EC is used to produce an approximately normally distributed data set. The data set was chosen since

S. R. Yates; A. W. Warrick; D. E. Myers

1986-01-01

142

Laboratory spectroscopic diagnostics of TLE-like air plasmas: methods to derive the rotational (gas) temperature in TLEs  

NASA Astrophysics Data System (ADS)

Laboratory low pressure (0.1 mbar < p < 2 mbar) glow air discharges have been studies by optical emission spectroscopy to illustrate several spectroscopic techniques that, depending on the available spectral resolution, could be implemented by different field spectrographs to experimentally quantify the gas temperature associated with Transient Luminous Events (TLEs) occurring at different altitudes including blue jets, giant blue jets and sprites. The laboratory air plasmas investigated have been analysed from the near UV (300 nm) to the near IR (1060 nm) with high (up to 0.01 nm) and low (2 nm) spectral resolution commercial grating spectrographs and by an in-house developed intensified CCD grating spectrograph that we have recently developed in our group at IAA - CSIC for TLE spectral diagnostic surveys with 0.45 nm spectral resolution. We discuss the results of laboratory tests and comment on the convenience of using one or another technique for rotational (gas) temperature determination during TLE spectroscopic campaigns. Finally, we will also show a comparison of the vibrational distribution function (VDF) of N2(B) obtained from (a) experiments in low pressure laboratory air plasmas produced in conditions similar to TLEs, (b) spectroscopic emissions from real TLE air plasmas and (c) compute from kinetic modeling.

Gordillo-Vazquez, F.; Parra-Rojas, F.; Passas, M.; Carrasco, E.; Luque, A.; Tanarro, I.; Simek, M.

2013-12-01

143

Astrometric Spectroscopic  

E-print Network

The Astrometric and Spectroscopic Parallaxes of Three Dwarf Novae (SS Aur, U Gem, and SS Cyg) ­­­T, covering the region 2.18 to 2.30 µm, for U Gem and SS Aur, and lower resolution (15�/pix) for all three DN vs. M V for the three DN. The moderate resolution spectra of SS Aur, U Gem, and the late­type dwarf

Harrison, Thomas

144

Organic matter characterization by infrared spectroscopic methods in lake sediment records from boreal and subarctic Sweden: Implications for long-term carbon cycling  

NASA Astrophysics Data System (ADS)

Freshwater systems play an important role in the global carbon cycle. In this dynamic system, inorganic and organic carbon can be incorporated into biota, effluxed to the atmosphere or accumulated in sediments. The amount and composition of the carbon, derived from both aquatic and terrestrial sources, accumulated in sediments depend on the climatic and environmental conditions present in the lake and its catchment, and are thus sensitive to changes in, e.g., temperature, precipitation, vegetation and hydrological flow patterns. In this study, we show the application of infrared spectroscopic methods to qualitatively and quantitatively characterize organic matter stored in lake sediments with a focus on changes in the source of terrestrial-derived organic matter. Infrared spectroscopic methods facilitate a fast, cost-efficient and non-destructive analysis of minerogenic as well as organic sediment components. We applied three different infrared spectroscopic analyses - visible-near infrared spectroscopy (VNIRS; 25000-4000 cm-1), Fourier-transform infrared spectroscopy in the mid-IR region (FTIR; 3750-400 cm-1) and a combined Fourier-transformed infrared - thermal programmed desorption technique (FTIR-TPD; 3750-400 cm-1) - to Holocene sediment records from two Swedish lakes, Lång-Älgsjön and Lake Koukkel, to reconstruct past changes in the organic matter composition. The infrared spectral information of these records indicate sections of different organic matter composition reflecting varying stages of the lake and landscape development. An early-Holocene mire development around the boreal lake Lång-Älgsjön led to an increased input of organic matter from the catchment into the lake initiating an early natural lake acidification, whereas the subarctic Lake Koukkel has been affected by mire and potentially late-Holocene permafrost dynamics, which caused an increased and less variable input of allochthonous organic matter. Overall, variations in organic matter composition seem mainly driven by changes in the landscape rather than any direct effects of successive climate changes. Our findings emphasize that infrared spectroscopic methods are a promising tool for the fast and cost-effective characterization of organic matter in sediment samples, particularly with regard to the detection of qualitative differences between samples. An improved understanding of past variations in the organic matter composition and the related processes driving these changes is essential to further understand the interactions in the carbon cycle between the terrestrial and aquatic systems.

Meyer-Jacob, Carsten; Rosén, Peter; Bindler, Richard

2013-04-01

145

Spectroscopic detection  

DOEpatents

In embodiments, spectroscopic monitor monitors modulated light signals to detect low levels of contaminants and other compounds in the presence of background interference. The monitor uses a spectrometer that includes a transmissive modulator capable of causing different frequency ranges to move onto and off of the detector. The different ranges can include those with the desired signal and those selected to subtract background contributions from those with the desired signal. Embodiments of the system are particularly useful for monitoring metal concentrations in combustion effluent.

Woskov, Paul P. (Bedford, MA); Hadidi, Kamal (Cambridge, MA)

2003-01-01

146

Example Resumes  

NSDL National Science Digital Library

This resource, created by the ATE National Resource Center, provides sample resumes for those in the field of engineering. The resource provides sample resumes in chemical engineering, civil engineering, computer technology, electronic engineering technology, information technology and graphic design. For more generic examples, the site provides two chronological resumes, two functional resumes, a hybrid resume and a resume for recent graduates. Additionally, example cover letters are also provided. This is a great resource for those looking to either create or simply enhance their current resumes. The site caters towards those in the field of engineering but could also be used across different disciplines. All resumes are formatted as pdf files.

2009-10-06

147

Spectroscopic Infrared Ellipsometry  

E-print Network

Spectroscopic Infrared Ellipsometry: Components, Calibration, and Application #12;CIP-DATA KONINKLIJKE BIBLIOTHEEK, DEN HAAG Boer, Johannes Henricus Wilhelmus Gerardus den Spectroscopic Infrared in Dutch. ISBN 90 386 0017 8 Subject headings: spectroscopy ellipsometry infrared. #12;Spectroscopic

Eindhoven, Technische Universiteit

148

Application of spectroscopic and computational methods in the study of the electronic excitations of partially silylated hydroxyquinones  

NASA Astrophysics Data System (ADS)

The silylation of hydroxynaphthoquinones and hydroxyanthraquinones with N-methyl- N-( tert-butyldimethylsilyl)-2,2,2-trifluoroacetamide, in one step reaction, under mild conditions, has led, in nearly quantitative yields, to the isolation of hydrolytically stable partially silylated products (only of the hydroxyl groups), which differ dramatically in color from the starting materials. The spectroscopic investigation of the silylated products in solution as well as the correlation of the observed data with computationally derived results have been carried out within a study aiming at the understanding of the visible maxima shift to either the ultraviolet or near-infrared region of the electromagnetic spectrum, which would imply availability of the silylated products in a variety of related applications.

Bakola-Christianopoulou, M. N.; Apazidou, K. K.; Stoyanov, S.; Akrivos, P. D.

2003-03-01

149

Measurements of internal distance changes of the 30S ribosome using FRET with multiple donor-acceptor pairs: quantitative spectroscopic methods.  

PubMed

We present analytical and experimental procedures for determining distance changes within the 30 S subunit of the Escherichia coli ribosome using Förster resonance energy transfer (FRET). We discuss ways to contend with complexities when using FRET to measure distance changes within large multi-subunit macromolecular complexes, such as the ribosome. Complications can arise due to non-stoichiometric labeling of donor and acceptor probes, as well as environmental effects that are specific to each conjugation site. We show how to account for changes in extinction coefficients, quenching, labeling stoichiometry and other variations in the spectroscopic properties of the dye to enable more accurate calculation of distances from FRET data. We also discuss approximations that concern the orientation of the transition moments of the two dye molecules, as well as the impact of other errors in the measurement of absolute distances. Thirteen dye-pair locations with different distances using 18 independent FRET pairs conjugated to specific 30 S protein residues have been used to determine distance changes within the 30 S subunit upon association with the 50 S subunit, forming the 70 S ribosome. Here, we explain the spectroscopic methods we have used, which should be of general interest in studies that aim at obtaining quantitative distance information from FRET. PMID:16055154

Majumdar, Zigurts K; Hickerson, Robyn; Noller, Harry F; Clegg, Robert M

2005-09-01

150

Studies on the interactions of SAP-1 (an N-terminal truncated form of cystatin S) with its binding partners by CD-spectroscopic and molecular docking methods.  

PubMed

SAP-1 is a 113 amino acid long single-chain protein which belongs to the type 2 cystatin gene family. In our previous study, we have purified SAP-1 from human seminal plasma and observed its cross-class inhibitory property. At this time, we report the interaction of SAP-1 with diverse proteases and its binding partners by CD-spectroscopic and molecular docking methods. The circular dichroism (CD) spectroscopic studies demonstrate that the conformation of SAP-1 is changed after its complexation with proteases, and the alterations in protein secondary structure are quantitatively calculated with increase of ?-helices and reduction of ?-strand content. To get insight into the interactions between SAP-1 and proteases, we make an effort to model the three-dimensional structure of SAP-1 by molecular modeling and verify its stability and viability through molecular dynamics simulations and finally complexed with different proteases using ClusPro 2.0 Server. A high degree of shape complementarity is examined within the complexes, stabilized by a number of hydrogen bonds (HBs) and hydrophobic interactions. Using HB analyses in different protein complexes, we have identified a series of key residues that may be involved in the interactions between SAP-1 and proteases. These findings will assist to understand the mechanism of inhibition of SAP-1 for different proteases and provide intimation for further research. PMID:24261636

Yadav, Vikash Kumar; Mandal, Rahul Shubhra; Puniya, Bhanwar Lal; Singh, Sarman; Yadav, Savita

2015-01-01

151

Testing Examples: A Guide.  

ERIC Educational Resources Information Center

Shows how and why errors get introduced into examples in computer software documentation and what actions technical communicators can take to minimize this occurrence. Proposes a method to test examples. Suggests that technical writers can avoid these sources of error by creating and implementing a good test plan, maintaining and updating the…

Bist, Gary

1995-01-01

152

Thin layers in electrical engineering-example of shell models in analysing eddy-currents by boundary and finite element methods  

Microsoft Academic Search

The authors propose a didactical approach to thin regions in electromagnetics and, as an example, derive the boundary conditions and surface equation for eddy currents flowing inside a thin ferromagnetic shell. The numerical tests are done using the boundary-element-method (BEM) software package PH13-D, but the results could easily be transposed in a finite-element-method (FEM) context. The practical applications my concern

L. Krahenbuhl; D. Muller

1993-01-01

153

Insight into the roles of earthworm in vermicomposting of sewage sludge by determining the water-extracts through chemical and spectroscopic methods.  

PubMed

This work illustrated the effects of earthworm in vermicomposting (Eisenia fetida) by determining the water-extracts through chemical and spectroscopic methods. A field experiment with sludge as the only feed was subjected to vermicomposting and the control (without worms) for three weeks. Compared to the control, vermicomposting resulted in lower pH and water-extractable organic carbon (WEOC) along with higher electrical conductivity (EC). Moreover, vermicomposting caused nearly two times higher content of water-extractable nitrate (WEN-NO3(-)) than the control. Furthermore, fourier transform infrared spectra (FT-IR) revealed that vermicomposting promoted the hydrolysis/transformation of macromolecular organic matters and accelerated the degradation of polysaccharide-like and protein-like materials. Fluorescence spectroscopy also reflected vermicomposting led to higher humification degree than the control. In all, this study supplies a new view to assess the roles of earthworm in vermicomposting of sewage sludge by evaluating the water extracts. PMID:24384315

Yang, Jian; Lv, Baoyi; Zhang, Jie; Xing, Meiyan

2014-02-01

154

PNS and statistical experiments simulation in subcritical systems using Monte-Carlo method on example of Yalina-Thermal assembly  

NASA Astrophysics Data System (ADS)

In subcritical systems driven by an external neutron source, the experimental methods based on pulsed neutron source and statistical techniques play an important role for reactivity measurement. Simulation of these methods is very time-consumed procedure. For simulations in Monte-Carlo programs several improvements for neutronic calculations have been made. This paper introduces a new method for simulation PNS and statistical measurements. In this method all events occurred in the detector during simulation are stored in a file using PTRAC feature in the MCNP. After that with a special code (or post-processing) PNS and statistical methods can be simulated. Additionally different shapes of neutron pulses and its lengths as well as dead time of detectors can be included into simulation. The methods described above were tested on subcritical assembly Yalina-Thermal, located in Joint Institute for Power and Nuclear Research SOSNY, Minsk, Belarus. A good agreement between experimental and simulated results was shown.

Sadovich, Sergey; Talamo, A.; Burnos, V.; Kiyavitskaya, H.; Fokov, Yu.

2014-06-01

155

An Updated Method for the Measurement of Silicon Isotopes From Opal, Examples From Cariaco Basin Sediment Traps  

NASA Astrophysics Data System (ADS)

We modified a new method for the complete digestion of silicate minerals (van den Boorn et al., 2006, JAAS, 21, 734-742), replacing a Parr bomb NaOH digestion with a hot plate digestion using Teflon beakers. The method is ideal for amorphous silicate minerals such as opal, and has been tested using diatoms recovered from the >125 ?m fraction of sediment trap samples from the Cariaco Basin. A complete digestion of these samples was achieved using this revised method. The method has been used to prepare samples for silicon (Si) isotope analyses on a Neptune MC-ICPMS. The MC-ICPMS method was tested using the Si isotope reference material 'big batch', correcting for mass bias by standard-sample bracketing. The ?29Si and ?30Si values of big batch, normalized to NIST RM-8546 (formerly NBS-28), are in agreement with published values (van den Boorn et al., 2006). This method will be evaluated with other Si reference materials (e.g., diatomite). Ultimately the new digestion method and MC-ICPMS method will be used to measure Si isotope variability in diatoms from the Cariaco Basin sediment trap samples. Furthermore, replicates will be used in an interlaboratory calibration to test the reproducibility between different techniques (e.g., MC-ICPMS vs. gas source).

Scher, H. D.; Thunell, R. C.; Delaney, M. L.

2007-12-01

156

Selection method of quasi-continuous wavelength combination with applications to the near-infrared spectroscopic analysis of soil organic matter.  

PubMed

Equidistant combination multiple linear regression (EC-MLR) for the quasi-continuous wavelength selection of spectroscopic analysis was proposed and successfully applied to the reagent-free determination of soil organic matter with near-infrared spectroscopy. For comparison, the continuous-mode moving window partial least squares (MWPLS) and the discrete-mode successive projections algorithm (SPA) were improved by considering the stability and applied to the same analysis object as well. All methods exhibited good effect, but the modeling accuracy, stability, and validation effect of EC-MLR were better than that of the other two methods. Compared with MWPLS, the optimal EC-MLR model contained only 16 wavelengths, and method complexity was substantially reduced. Compared with SPA-MLR, the optimal EC-MLR model could easily undergo spectral preprocessing to improve predictive capability. Moreover, appropriate equidistant discrete wavelength combination with EC-MLR corresponded to the spectral absorption band with proper resolution and can effectively overcome co-linearity interruption for the MLR model. Thus, the EC-MLR method has great potential in practical application and instrument design. PMID:24666942

Pan, Tao; Li, Minmiao; Chen, Jiemei

2014-01-01

157

Catalase in fluvial biofilms: a comparison between different extraction methods and example of application in a metal-polluted river  

Microsoft Academic Search

Antioxidant enzymes are involved in important processes of cell detoxification during oxidative stress and have, therefore,\\u000a been used as biomarkers in algae. Nevertheless, their limited use in fluvial biofilms may be due to the complexity of such\\u000a communities. Here, a comparison between different extraction methods was performed to obtain a reliable method for catalase\\u000a extraction from fluvial biofilms. Homogenization followed

Chloé Bonnineau; Berta Bonet; Natàlia Corcoll; Helena Guasch

2011-01-01

158

AquaFuel: An example of the emerging new energies and the new methods for their scientific study  

E-print Network

In this paper we initiate studies of the emerging new forms of energy by using as a representative example the new combustible gas called AquaFuel, discovered and patented by William H. Richardson, jr., whose rights are now owned by Toups Technology Licensing, Inc. (TTL), of Largo, Florida. In essence, AquaFuel is a new energy converter capable of transforming Carbon and water into a new combustible gas via an electric discharge. We show that AquaFuel can be produced easily, safely and rapidly in large amounts, and exhibits greatly reduced emission pollutants as compared to fossil fuels of current use. Despite its simplicity, the chemical and physical characteristics of AquaFuel are largely unknown at this writing. We then review nine basic experimental measurements which are necessary for a scientific appraisal of AquaFuel. We outline the limitations of quantum mechanics and chemistry for the treatment of {\\it new} forms of energy, namely, energies which by definition should be {\\it beyond} said theories. We finally point out the availability of broader theories specifically constructed for the study of new energies and point out available applications.

Ruggero Maria Santilli

1998-05-23

159

Comparison of correction methods of inhomogeneities in daily data on example of Central European temperature and precipitation series  

NASA Astrophysics Data System (ADS)

Prior any data analysis, data quality control and homogenization have to be undertaken to get rid of erroneous values in time series. In this work we focused especially on comparison of methods for daily data inhomogeneities correction. Two basic approaches for inhomogeneity adjustments were adopted and compared: (i) "delta" method - adjustment of monthly series and projection of estimated smoothed monthly adjustments into annual variation of daily adjustments and (ii) "variable" correction of daily values according to the corresponding percentiles. "Variable" correction methods were investigated more deeply and their results were mutually compared. The methods used were HOM of Paul Della-Marta, SPLIDHOM of Olivier Mestre and a new method of Petr Stepanek. For the calculation, the software ProClimDB has been combined with R software scripts containing HOM and SPLIDHOM and the different methodological approaches were applied to daily data of various meteorological elements measured in the area of the Czech Republic. The tool is open and freely available. Series were processed by means of the developed ProClimDB and AnClim software (www.climahom.eu).

Stepanek, P.; Gruber, Ch.; Zahradnicek, P.

2009-04-01

160

NMR, FT-IR, FT-Raman, UV spectroscopic, HOMO-LUMO and NBO analysis of cumene by quantum computational methods  

NASA Astrophysics Data System (ADS)

This work presents the investigation of cumene using the FT-IR, FT-Raman, NMR and UV spectra obtained through various spectroscopic techniques. The theoretical vibrational frequencies and optimized geometric parameters have been calculated by using HF and density functional theory with the hybrid methods B3LYP, B3PW91 and 6-311+G(d,p)/6-311++G(d,p) basis sets. The theoretical vibrational frequencies have been scaled and compared with the corresponding experimental data. 1H and 13C NMR spectra were recorded and chemical shifts of the molecule were compared to TMS by using the Gauge-Independent Atomic Orbital (GIAO) method. A study on the electronic and optical properties, absorption wavelengths, excitation energy, dipole moment and frontier molecular orbital energies, and potential energy surface (PES) is performed using HF and DFT methods. The thermodynamic properties (heat capacity, entropy and enthalpy) at different temperatures are also calculated. NBO analysis is carried out to picture the charge transfer between the localized bonds and lone pairs. NLO properties related to polarizability and hyperpolarizability are also discussed.

Sivaranjani, T.; Xavier, S.; Periandy, S.

2015-03-01

161

A high-resolution phosphorus-31 nuclear magnetic resonance (NMR) spectroscopic method for the non-phosphorus markers of chemical warfare agents.  

PubMed

A high-resolution phosphorus-31 nuclear magnetic resonance (NMR) spectroscopic method has been developed for detection, identification and quantification of non-phosphorus markers of toxic nerve agents (soman and V-class), vesicants (HD, HN-2, HN-3), and incapacitating agent (Bz). These analytes were converted to phosphorus-containing derivatives via phosphitylation reaction of their hydroxyl and sulfhydryl functions (using 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane). This was followed by (31)P{(1)H} and (31)P NMR analysis of these derivatives. The chemical shifts (?) and coupling constants ((3)J(P-H)) of derivatives were used for their specific detection and identification. The method allowed clear distinction between the alcohols and thiols. The lower limits of detection of these analytes were found to be between 12 and 28 ?g obtained from 128 transients of (31)P{(1)H} quantitative NMR experiments. Utility of the method was ensured by the detection and identification of triethanolamine present (at an original concentration of 5 ?g/mL) in an aqueous sample from 28th OPCW Official Proficiency Tests. PMID:22160203

Mazumder, Avik; Kumar, Ajeet; Purohit, Ajay K; Dubey, Devendra K

2012-02-01

162

3D seismic travel time surveying a comparison of the time term method and tomography (an example from an archaeological site)  

NASA Astrophysics Data System (ADS)

The seismic tomography is an almost exclusive method in routine interpretation of 3D refraction datasets. However, the gradient model usually used for the tomography methods might not always be the most suitable one. In some cases, the layer-based model might be more appropriate. In this article, one simple layer-based approach is introduced, based on a modification of the time-term method. It enables computation of lateral velocity changes of a refractor in highly heterogeneous media. Applications and results of these two methods are then compared on the example of a seismic survey at a medieval castle. This case study proved that the time-term approach may yield results which surpass the tomography ones. However, a combination of the two methods is recommended.

Valenta, J.; Dohnal, J.

2007-09-01

163

Chloride mass-balance method for estimating ground water recharge in arid areas: Examples from western Saudi Arabia  

USGS Publications Warehouse

The chloride mass-balance method, which integrates time and aerial distribution of ground water recharge, was applied to small alluvial aquifers in the wadi systems of the Asir and Hijaz mountains in western Saudi Arabia. This application is an extension of the method shown to be suitable for estimating recharge in regional aquifers in semi-arid areas. Because the method integrates recharge in time and space it appears to be, with certain assumptions, particularly well suited for and areas with large temporal and spatial variation in recharge. In general, recharge was found to be between 3 to 4% of precipitation - a range consistent with recharge rates found in other arid and semi-arid areas of the earth.

Bazuhair, A.S.; Wood, W.W.

1996-01-01

164

[X-ray radiography as a method of detailing the analysis of sedimentary facies, based on example of the Cergowa sandstones (Flysch Carpathians)].  

PubMed

The paper presents the X-ray radiography as a method useful for the visualization of sedimentary structures in macroscopically homogeneous rocks. The radiographic analysis presented here bases on the example the Cergowa turbidite sandstones. The applied technique reveals that some of the apparently homogeneus Cergowa sandstones possess internal sedimentary structure of cross-lamination, which reflects on the sedimentological interpretation of the depositional mechanisms of this rock unit. This is the first application of this method in research on the Carpathian Flysch sedimentation. PMID:23944113

Pszonka, Joanna; Wendorff, Marek; Jucha, Katarzyna; Bartynowska, Karolina; Urbanik, Andrzej

2013-01-01

165

Method of Determining the Filtration Properties of oil-Bearing Crops in the Process of Their Pressing by the Example of Rape-oil Extrusion  

NASA Astrophysics Data System (ADS)

A method of determining the change in the fi ltration properties of oil-bearing crops in the process of their pressing by repeated dynamic loading is proposed. The use of this method is demonstrated by the example of rape-oil extrusion. It was established that the change in the mass concentration of the oil in a rape mix from 0.45 to 0.23 leads to a decrease in the permeability of the mix by 101.5-102 times depending on the pressure applied to it. It is shown that the dependence of the permeability of this mix on the pressure applied to it is nonmonotone in character.

Slavnov, E. V.; Petrov, I. A.

2014-07-01

166

A Simple Method to Predict Regional Fish Abundance: An Example in the McKenzie River Basin, Oregon  

EPA Science Inventory

Regional assessments of fisheries resources are increasingly called for, but tools with which to perform them are limited. We present a simple method that can be used to estimate regional carrying capacity and apply it to the McKenzie River Basin, Oregon. First, we use a macroeco...

167

Towards a Comprehensive Method for Evaluating Social Studies Curriculum Materials: With Examples from the Elementary School Curriculum.  

ERIC Educational Resources Information Center

The evaluation methodology delineated in this paper is a work in progress. The purpose is to develop a method for evaluating social studies curriculum materials that encompasses the materials' comprehensibility and the perspective offered. The paper draws from past evaluations that focused on either comprehensibility or perspective but have not…

Bisland, Beverly Milner

168

Comparative Methods for the Analysis of Gene-Expression Evolution: An Example Using Yeast Functional Genomic Data  

E-print Network

database from genomic and developmental studies, we are lacking quantitative methods for analyzing the evolution of gene function is a primary challenge of modern evolutionary biology. Despite an expanding variation, a major focus of biology has been to understand the evolution of gene function. Despite

Abouheif, Ehab

169

Spectroscopic diffraction phase microscopy.  

PubMed

We present spectroscopic diffraction phase microscopy (sDPM) as a method capable of measuring quantitative phase images at multiple wavelengths. sDPM uses a spatial light modulator at the Fourier plane of a lens to select desired wavelengths from the white light illumination of a grating. The quantitative phase information at different wavelengths allows us to decouple the refractive index and the thickness from the phase shift induced by biological cells. We demonstrate the capability of the setup by dispersion measurements of microsphere beads and RBCs. PMID:23381283

Pham, Hoa; Bhaduri, Basanta; Ding, Huafeng; Popescu, Gabriel

2012-08-15

170

Switching spectroscopic measurement of surface potentials on ferroelectric surfaces via an open-loop Kelvin probe force microscopy method  

NASA Astrophysics Data System (ADS)

We report a method for switching spectroscopy Kelvin probe force microscopy (SS-KPFM). The method is established as a counterpart to switching spectroscopy piezoresponse force microscopy (SS-PFM) in Kelvin probe force microscopy. SS-KPFM yields quantitative information about the surface charge state during a local bias-induced polarization switching process, complementary to the electromechanical coupling properties probed via SS-PFM. Typical ferroelectric samples of a Pb-based relaxor single crystal and a BiFeO3 thin film were investigated using both methods. We briefly discuss the observed surface charging phenomena and their influence on the associated piezoresponse hysteresis loops.

Li, Qian; Liu, Yun; Wang, Danyang; Withers, Ray L.; Li, Zhenrong; Luo, Haosu; Xu, Zhuo

2012-12-01

171

A target enrichment method for gathering phylogenetic information from hundreds of loci: An example from the Compositae1  

PubMed Central

• Premise of the study: The Compositae (Asteraceae) are a large and diverse family of plants, and the most comprehensive phylogeny to date is a meta-tree based on 10 chloroplast loci that has several major unresolved nodes. We describe the development of an approach that enables the rapid sequencing of large numbers of orthologous nuclear loci to facilitate efficient phylogenomic analyses. • Methods and Results: We designed a set of sequence capture probes that target conserved orthologous sequences in the Compositae. We also developed a bioinformatic and phylogenetic workflow for processing and analyzing the resulting data. Application of our approach to 15 species from across the Compositae resulted in the production of phylogenetically informative sequence data from 763 loci and the successful reconstruction of known phylogenetic relationships across the family. • Conclusions: These methods should be of great use to members of the broader Compositae community, and the general approach should also be of use to researchers studying other families. PMID:25202605

Mandel, Jennifer R.; Dikow, Rebecca B.; Funk, Vicki A.; Masalia, Rishi R.; Staton, S. Evan; Kozik, Alex; Michelmore, Richard W.; Rieseberg, Loren H.; Burke, John M.

2014-01-01

172

Study of XAFS spectroscopic methods of speciation using mixtures of Cu(I) and Cu(II) chlorides  

NASA Astrophysics Data System (ADS)

Speciation concerns determination of the chemical forms along with the relative quantities of the different species in a given sample. The aim of the present work is to make a comparative study of the different methods of speciation using X-ray absorption fine structure (XAFS) spectroscopy. For this purpose, mixtures have been prepared by mixing CuCl2 and CuCl in different proportions. The X-ray absorption spectra have been recorded at the copper K-edge in the mixtures and the two chlorides separately. The different characteristic features of the XANES spectra of the two chlorides, useful for speciation, have been identified. Firstly, Principal component analysis (PCA) and target transformation (TT) methods have been used to check the number and identity of components in the mixtures. After the identification of the components, the percentages of the species in the mixtures have been quantitatively determined by linear combination fitting (LCF) of XANES, derivative XANES, and EXAFS (k3chi and k2chi) spectra. The other methods of speciation which have been employed are normalized difference absorption edge spectra analysis (NDAES), methods based on derivative XANES spectra of species and the method based on the relative position of the absorption edge. Results obtained from these methods have been compared and their relative merits discussed. It is probably for the first time that such a study has been done. The first section in your paper

Gaur, A.; Shrivastava, B. D.; Khalid, S.

2013-04-01

173

Switching industrial production processes from complex to defined media: method development and case study using the example of Penicillium chrysogenum  

PubMed Central

Background Filamentous fungi are versatile cell factories and widely used for the production of antibiotics, organic acids, enzymes and other industrially relevant compounds at large scale. As a fact, industrial production processes employing filamentous fungi are commonly based on complex raw materials. However, considerable lot-to-lot variability of complex media ingredients not only demands for exhaustive incoming components inspection and quality control, but unavoidably affects process stability and performance. Thus, switching bioprocesses from complex to defined media is highly desirable. Results This study presents a strategy for strain characterization of filamentous fungi on partly complex media using redundant mass balancing techniques. Applying the suggested method, interdependencies between specific biomass and side-product formation rates, production of fructooligosaccharides, specific complex media component uptake rates and fungal strains were revealed. A 2-fold increase of the overall penicillin space time yield and a 3-fold increase in the maximum specific penicillin formation rate were reached in defined media compared to complex media. Conclusions The newly developed methodology enabled fast characterization of two different industrial Penicillium chrysogenum candidate strains on complex media based on specific complex media component uptake kinetics and identification of the most promising strain for switching the process from complex to defined conditions. Characterization at different complex/defined media ratios using only a limited number of analytical methods allowed maximizing the overall industrial objectives of increasing both, method throughput and the generation of scientific process understanding. PMID:22727013

2012-01-01

174

Novel Method To Identify the Optimal Antimicrobial Peptide in a Combination Matrix, Using Anoplin as an Example  

PubMed Central

Microbial resistance is an increasing health concern and a true danger to human well-being. A worldwide search for new compounds is ongoing, and antimicrobial peptides are promising lead candidates for tomorrow's antibiotics. The decapeptide anoplin (GLLKRIKTLL-NH2) is an especially interesting candidate because of its small size as well as its antimicrobial and nonhemolytic properties. Optimization of the properties of an antimicrobial peptide such as anoplin requires multidimensional searching in a complex chemical space. Typically, such optimization is performed by labor-intensive and costly trial-and-error methods. In this study, we show the benefit of fractional factorial design for identification of the optimal antimicrobial peptide in a combination matrix. We synthesized and analyzed a training set of 12 anoplin analogs, representative of 64 analogs in total. Using MIC, hemolysis, and high-performance liquid chromatography retention time data, we constructed analysis-of-variance models that describe the relationship between these properties and the structural characteristics of the analogs. We show that the mathematical models derived from the training set data can be used to predict the properties of other analogs in the chemical space. Hence, this method provides an efficient means of identification of the optimal peptide in the searched chemical space. PMID:24277042

Ritz, C.; Fliedner, F. P.; Frimodt-Møller, N.

2014-01-01

175

Methodical questions and accuracy problems of GPS observations by the example of the geodynamic proving ground in Bishkek  

NASA Astrophysics Data System (ADS)

The key questions concerning the modern methodical tasks and accuracy of GPS measurements of crustal motion spanning are discussed for a full cycle of the survey from the organization of the field operations to the interpretation of the final results. The presented data rely on the 20-year experience of the geophysicists of the Research Station of the Russian Academy of Sciences in Bishkek (RS RAS) in GPS monitoring at the Geodynamic Proving Ground in Bishkek (GPGB) and in a large part of Central Asia. The comparative characteristics of the constellations of visible GPS and GLONASS satellites are analyzed from the standpoint of their practical application for precise scientific observations of crustal motions. The studies of the contemporary movements of the Earth's crust by the methods of satellite geodesy generally comprise three stages: (1) organization of the measurement networks and acquisition of the data; (2) data processing; and (3) interpretation of the results. Each stage is associated with its own block of the tasks and problems, and neither is guaranteed against uncertainties and errors which may affect the results, conclusions, and reconstructions.

Kuzikov, S. I.

2014-11-01

176

'Dialectical process' and 'constructive method': micro-analysis of relational process in an example from parent-infant psychotherapy.  

PubMed

Jung defined experience that takes place between therapist and patient as 'dialectical process', achieved through 'constructive method'. Perspectives from attachment theory, neurobiology, cognitive science, systems thinking and infancy research confirm and extend his view of the centrality of relational process in the development of self. Interactional experiences are embedded within the history of the primary parent-infant relationship and structure within the mind implicit patterns of relating. These patterns influence capacities for managing a whole lifetime of affective relational experience within the self and with others. This paper shows how parent-infant psychotherapy seeks to intervene during the formation of disturbed relational patterns. I offer detailed micro-analysis of the moment-to-moment 'dialectical process' that a mother, her four-month-old infant and myself 'constructed' together. PMID:15032926

Woodhead, Judith

2004-04-01

177

Statistical analysis of astronomical data containing upper bounds - General methods and examples drawn from X-ray astronomy  

NASA Technical Reports Server (NTRS)

Statistical procedures taken from the field of survival analysis have been adapted to astronomical usage and have been applied to a sample of stars in the B-V color range between 0.1 and 0.5 with measured soft X-ray luminosities and projected equatorial velocities. The two-sample problem and linear regression problem with arbitrarily censored data were studied. A new method for determining the linear regression between two random variables in the presence of arbitrary censoring has been developed which can also be used for a likelihood-ratio test for the independence of two random variables and for principal-component analysis in the presence of arbitrary censoring. The required numerical computations can be carried out straightforwardly and rapidly.

Schmitt, J. H. M. M.

1985-01-01

178

An exploratory method to detect tephras from quantitative XRD scans: Examples from Iceland and east Greenland marine sediments  

USGS Publications Warehouse

Tephras, mainly from Iceland, are becoming increasingly important in interpreting leads and lags in the Holocene climate system across NW Europe. Here we demonstrate that Quantitative Phase Analysis of x-ray diffractograms of the 150 um fraction and identify these same peaks in XRD scans - two of these correlate geochemically and chronologically with Hekla 1104 and 3. At a distal site to the WNW of Iceland, on the East Greenland margin (core MD99-2317), the weight% of volcanic glass reaches values of 11% at about the time of the Saksunarvatn tephra. The XRD method identifies the presence of volcanic glass but not its elemental composition; hence it will assist in focusing attention on specific sections of sediment cores for subsequent geochemical fingerprinting of tephras. ?? 2006 SAGE Publications.

Andrews, J.T.; Eberl, D.D.; Kristjansdottir, G.B.

2006-01-01

179

Nuclear magnetic resonance, vibrational spectroscopic studies, physico-chemical properties and computational calculations on (nitrophenyl) octahydroquinolindiones by DFT method  

NASA Astrophysics Data System (ADS)

In the present study, 2?-nitrophenyloctahydroquinolinedione and its 3?-nitrophenyl isomer were synthesized and characterized by FT-IR, FT-Raman, 1H NMR and 13C NMR spectroscopy. The molecular geometry, vibrational frequencies, 1H and 13C NMR chemical shift values of the synthesized compounds in the ground state have been calculated by using the density functional theory (DFT) method with the 6-311++G (d,p) basis set and compared with the experimental data. The complete vibrational assignments of wave numbers were made on the basis of potential energy distribution using GAR2PED programme. Isotropic chemical shifts for 1H and 13C NMR were calculated using gauge-invariant atomic orbital (GIAO) method. The experimental vibrational frequencies, 1H and 13C NMR chemical shift values were found to be in good agreement with the theoretical values. On the basis of vibrational analysis, molecular electrostatic potential and the standard thermodynamic functions have been investigated.

Pasha, M. A.; Siddekha, Aisha; Mishra, Soni; Azzam, Sadeq Hamood Saleh; Umapathy, S.

2015-02-01

180

Mass Spectroscopic Fingerprinting Method for Differentiation Between Scutellaria lateriflora and the Germander (Teucrium canadense and T. chamaedrys) Species  

PubMed Central

Scutellaria lateriflora, commonly known as skullcap, is used as an ingredient in numerous herbal products. However, it has been occasionally adulterated/contaminated with Teucrium canadense and T. chamaedrys, commonly known as germander, which contain hepatotoxic diterpenes. Due to the morphological similarities between the two genera, analytical methodologies to distinguish authentic S. lateriflora from the Teucrium species are needed to ensure public safety. In this study, a direct-injection electrospray ionization/MS method was used to generate spectral fingerprints of extracts from 21 skullcap and germander samples at a rate of 90 s/sample. MS fingerprints were analyzed by principal component analysis. The newly developed method offers a rapid and easy way to differentiate between skullcap and germander samples. PMID:20922946

Chen, Pei; Lin, Long-Ze; Harnly, James M.

2013-01-01

181

A method for the separation of beryllium from spectral interfering elements in inductively coupled plasma-atomic emission spectroscopic analysis  

Microsoft Academic Search

A quick, simple and effective chromatographic method for the separation of beryllium from a wide range of elements is described. The elements selected comprise elements which can interfere with the determination of beryllium by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and elements which commonly occur in environmental and industrial sample matrices. Beryllium is separated from all possible ICP-AES spectral interfering

Daniel R. McAlister; E. Philip Horwitz

2005-01-01

182

Study on photophysical and aggregation induced emission recognition of 1,8-naphthalimide probe for casein by spectroscopic method.  

PubMed

A novel water-soluble 1,8-naphthalimide derivative 1, bearing two acetic carboxylic groups, exhibited fluorescent turn-on recognition for casein based on the aggregation induced emission (AIE) character. The photophysical properties of 1 consisting of donor and acceptor units were investigated in different solutions. The fluorescence intensity decreased through taking advantage of twisted intramolecular charge transfer (TICT) and self-association emission with increasing solvent polarity. Moreover, the spectral red-shift and intensity quench in protic solvents were caused by the excited-state hydrogen bond strengthening effect. Density Functional Theory (DFT) calculations revealed that 1 exhibited a strong TICT character. The AIE mechanism of 1 with casein was due to 1 docked in the hydrophobic cavity between sub-micelles and bound with Tyr and Trp residues, resulting in the aggregation of 1 on the casein surface and emission enhancement. Based on this, a novel casein assay method was developed. The proposed exhibited a good linear range from 0.1 to 22 ?g mL(-1), with the detection limit of 2.8 ng mL(-1). Satisfactory reproducibility, reversibility and a short response time were realized. This method was applied to the determination of casein in milk powder samples and the results were in good agreement with the result of Biuret method. PMID:23454708

Sun, Yang; Liu, Zhen; Liang, Xuhua; Fan, Jun; Han, Quan

2013-05-01

183

Study on photophysical and aggregation induced emission recognition of 1,8-naphthalimide probe for casein by spectroscopic method  

NASA Astrophysics Data System (ADS)

A novel water-soluble 1,8-naphthalimide derivative 1, bearing two acetic carboxylic groups, exhibited fluorescent turn-on recognition for casein based on the aggregation induced emission (AIE) character. The photophysical properties of 1 consisting of donor and acceptor units were investigated in different solutions. The fluorescence intensity decreased through taking advantage of twisted intramolecular charge transfer (TICT) and self-association emission with increasing solvent polarity. Moreover, the spectral red-shift and intensity quench in protic solvents were caused by the excited-state hydrogen bond strengthening effect. Density Functional Theory (DFT) calculations revealed that 1 exhibited a strong TICT character. The AIE mechanism of 1 with casein was due to 1 docked in the hydrophobic cavity between sub-micelles and bound with Tyr and Trp residues, resulting in the aggregation of 1 on the casein surface and emission enhancement. Based on this, a novel casein assay method was developed. The proposed exhibited a good linear range from 0.1 to 22 ?g mL-1, with the detection limit of 2.8 ng mL-1. Satisfactory reproducibility, reversibility and a short response time were realized. This method was applied to the determination of casein in milk powder samples and the results were in good agreement with the result of Biuret method.

Sun, Yang; Liu, Zhen; Liang, Xuhua; Fan, Jun; Han, Quan

2013-05-01

184

Atomic absorption spectroscopic, conductometric and colorimetric methods for determination of fluoroquinolone antibiotics using ammonium reineckate ion-pair complex formation  

NASA Astrophysics Data System (ADS)

Three accurate, rapid and simple atomic absorption spectrometric, conductometric and colorimetric methods were developed for the determination of norfloxacin (NRF), ciprofloxacin (CIP), ofloxacin (OFL) and enrofloxacin (ENF). The proposed methods depend upon the reaction of ammonium reineckate with the studied drugs to form stable precipitate of ion-pair complexes, which was dissolved in acetone. The pink coloured complexes were determined either by AAS or colorimetrically at ?max 525 nm directly using the dissolved complex. Using conductometric titration, the studied drugs could be evaluated in 50% (v/v) acetone in the range 5.0-65, 4.0-48, 5.0-56 and 6.0-72 ?g ml -1 of NRF, CPF, OFL and ENF, respectively. The optimizations of various experimental conditions were described. The results obtained showed good recoveries of 99.15±1.15, 99.30±1.40, 99.60±1.50, and 99.00±1.25% with relative standard deviations of 0.81, 1.06, 0.97, and 0.69% for NRF, CPF, OFL, and ENF, respectively. Applications of the proposed methods to representative pharmaceutical formulations are successfully presented.

Ragab, Gamal H.; Amin, Alaa S.

2004-03-01

185

Structural and spectroscopic properties of LaOF:Eu3+ nanocrystals prepared by the sol-gel Pechini method.  

PubMed

A new method was used to obtain Eu(3+)-doped LaOF nanocrystals. The obtained nanocrystals were synthesized for the first time using a modified Pechini sol-gel method. The products were analyzed by X-ray powder diffraction and the Rietveld method. Optimal conditions for the synthesis were found. Luminescent properties of the tetragonal and rhombohedral LaOF:Eu(3+) nanocrystals were investigated by collecting excitation and luminescence spectra. The most effective dopant concentrations in both hosts were found. Luminescent lifetimes were also measured. The time-resolved luminescent traces showed both a growth and a decay, which pointed to energy transfer processes between Eu(3+) ions in the LaOF host. In order to explain these phenomena, an adequate mechanism has been proposed. Intensity parameters ?(2), ?(4) and quantum efficiencies were calculated using the Judd-Ofelt theory, allowing for an extensive study of the luminescent properties of Eu(3+) ion in the LaOF matrix. PMID:21805994

Grzyb, Tomasz; Lis, Stefan

2011-09-01

186

A proposed validation method for automated nucleic acid extraction and RT-qPCR analysis: an example using Bluetongue virus.  

PubMed

This study proposes a validation strategy for an automated extraction procedure, followed by RT-qPCR analysis. To avoid false-negative results, a triplex RT-qPCR was used which detects the target viral RNA, an internal and an external control. The methods to determine the validation parameters such as linearity, efficiency, analytical sensitivity, analytical specificity and intra- and interrun variability are described in detail. Special attention is given to the analytical sensitivity, which is determined by probit analysis. The limit of detection was set at the input concentration resulting in a positive result in 95% of the repeats. The intra- and interrun variability was analysed profoundly by testing samples covering a broad range of viral loads, from strong positive to weak positive. To increase the diagnostic capacity, the extraction protocol was automated with a JANUS Automated Workstation (PerkinElmer, Waltham, MA), which can extract 186 samples in 2h and 30 min. The automation of the extraction protocol implied some additional validation parameters to be determined such as position-effect, absence of cross-contamination and comparison with the manual protocol. These parameters give essential information about the performance of the robot and are of great importance when the automated assay is used in an accreditation system. PMID:20116401

Vandemeulebroucke, Elise; De Clercq, Kris; Van der Stede, Yves; Vandenbussche, Frank

2010-04-01

187

[Thoughts and methods of study on acupuncture medical history: an example of Mr. MA Ji-Xing].  

PubMed

Mr. MA Ji-xing has devoted himself into the study of acupuncture medical history for more than 70 years. As a result, a great work of Zhenjiuxue Tongshi (see text), History of Acupuncture-Moxibustion) has been completed. The author has expensively studied for history of acupuncture medicine in time and space. Base on abundant historical materials, deliberate textual research as well as strategically situated academic view, it is considered as a masterpiece of acupuncture on real significance. It is worthwhile to note that the book has a systematic and profound explanation on Bian-stone therapy, unearthed literature relics of acupuncture, the bronze figure or illustration of acupoint as well as special topics of Japan and Korea acupuncture history. Filled several gaps of the field, and explored some significant new paths of study, it laid the groundwork for the profound study and unscramble of traditional acupuncture theory as well as the investigation of the academic history, which is considered to have a profound and persistent influence. The careful sorting and profound digging of many distinguish thoughts and methods of Mr. MA Ji-xing in the study of acupuncture medical history has significant meaning in references and enlightenment of the future research on acupuncture medical history. PMID:24843982

Yang, Feng; Zhu, Ling

2014-03-01

188

Neutron Spectroscopic Factors from Transfer Reactions  

E-print Network

The present paper examines past measurements of the angular distributions for (d,p) and (p,d) reactions on targets with Z=3-24 leading to the ground states. The procedure is prescribed for extracting a conventional set of spectroscopic factors. Most of these spectroscopic factors agree well with large-basis shell model predictions. In all, the ground state neutron spectroscopic factors for 80 nuclei have been obtained. The consistency of the method is evaluated by comparing spectroscopic factors obtained separately in (p,d) and (d,p) reactions. The values correlate with Endt's compilation when available, but the current method is more general and the spectroscopic factor values obtained are more consistent with each other.

Jenny Lee; M. B. Tsang; W. G. Lynch

2006-02-19

189

Synthetic, Structural, Spectroscopic, and Theoretical Studies of Structural Isomers of the Cluster Pt(3)(&mgr;-PPh(2))(3)Ph(PPh(3))(2). A Unique Example of Core Isomerism in Phosphine Phosphido-Rich Clusters.  

PubMed

Two isomers of the phosphido-bridged platinum cluster Pt(3)(&mgr;-PPh(2))(3)Ph(PPh(3))(2) (2 and 3) have been isolated, and their structures have been solved by single-crystal X-ray diffraction. Compound 2 crystallizes in the orthorhombic space group Cmc2(1) with a = 22.192(10) Å, b = 17.650(9) Å, c = 18.182(8) Å, and Z = 4. Compound 3 crystallizes with 2 molecules of dichloromethane in the monoclinic space group C2/c with a = 21.390(10) Å, b = 18.471(9) Å, c = 19.021(11) Å, beta = 105.27(5) degrees, and Z = 4. The two isomers differ essentially in their metal-metal distances and Pt-(&mgr;-PPh(2))-Pt angles. Thus 2, having an imposed C(s) symmetry, contains a bent chain of metal atoms with two short Pt-Pt distances of 2.758(3) Å and a long separation of 3.586(2) Å. In 3, which has an imposed C(2) symmetry, the metal atoms form an isosceles triangle with two Pt-Pt distances of 2.956(3) Å and one of 3.074(4) Å. These isomers can be smoothly interconverted by changing the crystallization solvents. Solution and solid-state (31)P NMR studies have been performed in order to assign the resonances of the different P nuclei and relate their chemical shifts with their structural environments. Raman spectroscopy was used to assign the nu(Pt-Pt) modes of the two structural isomers. Theoretical studies based on extended Hückel calculations and using the fragment molecular orbital approach show that the isomer with the three medium Pt-Pt distances is slightly more stable, in agreement with earlier theoretical predictions. Cluster core isomerism remains a rare phenomenon, and the present example emphasizes the role and the importance of flexible phosphido bridges in stabilizing clusters as well as the unprecedented features which can be observed in phosphine phosphido-rich metal clusters. PMID:11666312

Bender, Robert; Braunstein, Pierre; Dedieu, Alain; Ellis, Paul D.; Huggins, Beth; Harvey, Pierre D.; Sappa, Enrico; Tiripicchio, Antonio

1996-02-28

190

EMERGING INFRARED LASER ABSORPTION SPECTROSCOPIC  

E-print Network

. Internal and external cavity-enhanced spectroscopies are two methods to increase the magnitude-reflector), such as light detection and ranging (LIDAR), differential optical ab- sorption spectroscopy (DOAS), laser ABSORPTION SPECTROSCOPIC TECHNIQUES FOR GAS ANALYSIS spectroscopy (LIBS), and fiber optic or waveguide

191

Retrieval of frequency spectrum from time-resolved spectroscopic data: comparison of Fourier transform and linear prediction methods.  

PubMed

Femtosecond time-resolved signals often display oscillations arising from the nuclear and electronic wave packet motions. Fourier power spectrum is generally used to retrieve the frequency spectrum. We have shown by numerical simulations and coherent phonon spectrum of single walled carbon nanotubes (SWCNT) that the Fourier power spectrum may not be appropriate to obtain the spectrum, when the peaks overlap with varying phases. Linear prediction singular value decomposition (LPSVD) can be a good alternative for this case. We present a robust way to perform LPSVD analysis and demonstrate the method for the chirality assignment of SWCNT through the time-domain coherent phonon spectroscopy. PMID:25606997

Eom, Intae; Yoon, Eunjin; Baik, Sung-Hoon; Lim, Yong-Sik; Joo, Taiha

2014-12-15

192

Nitranilic acid hexahydrate, a novel benchmark system of the Zundel cation in an intrinsically asymmetric environment: spectroscopic features and hydrogen bond dynamics characterised by experimental and theoretical methods.  

PubMed

Nitranilic acid (2,5-dihydroxy-3,6-dinitro-2,5-cyclohexadiene-1,4-dione) as a strong dibasic acid in acidic aqueous media creates the Zundel cation, H5O2(+). The structural unit in a crystal comprises (H5O2)2(+) (2,5-dihydroxy-3,6-dinitro-1,4-benzoquinonate)(2-) dihydrate where the Zundel cation reveals no symmetry, being an ideal case for studying proton dynamics and its stability. The Zundel cation and proton transfer dynamics are studied by variable-temperature X-ray diffraction, IR and solid-state NMR spectroscopy, and various quantum chemical methods, including periodic DFT calculations, ab initio molecular dynamics simulation, and quantization of nuclear motion along three fully coupled internal coordinates. The Zundel cation features a short H-bond with the O···O distance of 2.433(2) Å with an asymmetric placement of hydrogen. The proton potential is of a single well type and, due to the non-symmetric surroundings, of asymmetric shape. The formation of the Zundel cation is facilitated by the electronegative NO2 groups. The employed spectroscopic techniques supported by calculations confirm the presence of a short H-bond with a complex proton dynamics. PMID:24281720

Mol?anov, Krešimir; Stare, Jernej; Vener, Mikhail V; Koji?-Prodi?, Biserka; Mali, Gregor; Grdadolnik, Jože; Moha?ek-Grošev, Vlasta

2014-01-21

193

A new method of observing weak extended x-ray sources with the Reuven Ramaty High-Energy Solar Spectroscopic Imager  

SciTech Connect

We present a new method, fan-beam modulation, for observing weak extended x-ray sources with the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). This space-based solar x-ray and {gamma}-ray telescope has much greater sensitivity than previous experiments in the 3-25 keV range, but is normally not well suited to detecting extended sources since their signal is not modulated by RHESSI's rotating grids. When the spacecraft is offpointed from the target source, however, the fan-beam modulation time-modulates the transmission by shadowing resulting from exploiting the finite thickness of the grids. In this article we detail how the technique is implemented and verify its consistency with sources with clear known signals that have occurred during RHESSI offpointing: microflares and the Crab Nebula. In both cases the results are consistent with previous and complementary measurements. Preliminary work indicates that this new technique allows RHESSI to observe the integrated hard x-ray spectrum of weak extended sources on the quiet Sun.

Hannah, Iain G.; Hurford, Gordon J.; Hudson, Hugh S.; Lin, Robert P. [Space Sciences Laboratory, University of California at Berkeley, Berkeley, California 94720-7450 (United States)

2007-02-15

194

Insights into accelerated liposomal release of topotecan in plasma monitored by a non-invasive fluorescence spectroscopic method.  

PubMed

A non-invasive fluorescence method was developed to monitor liposomal release kinetics of the anticancer agent topotecan (TPT) in physiological fluids and subsequently used to explore the cause of accelerated release in plasma. Analyses of fluorescence excitation spectra confirmed that unencapsulated TPT exhibits a red shift in its spectrum as pH is increased. This property was used to monitor TPT release from actively loaded liposomal formulations having a low intravesicular pH. Mathematical release models were developed to extract reliable rate constants for TPT release in aqueous solutions monitored by fluorescence and release kinetics obtained by HPLC. Using the fluorescence method, accelerated TPT release was observed in plasma as previously reported in the literature. Simulations to estimate the intravesicular pH were conducted to demonstrate that accelerated release correlated with alterations in the low intravesicular pH. This was attributed to the presence of ammonia in plasma samples rather than proteins and other plasma components generally believed to alter release kinetics in physiological samples. These findings shed light on the critical role that ammonia may play in contributing to the preclinical/clinical variability and performance seen with actively-loaded liposomal formulations of TPT and other weakly-basic anticancer agents. PMID:25456833

Fugit, Kyle D; Jyoti, Amar; Upreti, Meenakshi; Anderson, Bradley D

2015-01-10

195

Nuclear magnetic resonance, vibrational spectroscopic studies, physico-chemical properties and computational calculations on (nitrophenyl) octahydroquinolindiones by DFT method.  

PubMed

In the present study, 2'-nitrophenyloctahydroquinolinedione and its 3'-nitrophenyl isomer were synthesized and characterized by FT-IR, FT-Raman, (1)H NMR and (13)C NMR spectroscopy. The molecular geometry, vibrational frequencies, (1)H and (13)C NMR chemical shift values of the synthesized compounds in the ground state have been calculated by using the density functional theory (DFT) method with the 6-311++G (d,p) basis set and compared with the experimental data. The complete vibrational assignments of wave numbers were made on the basis of potential energy distribution using GAR2PED programme. Isotropic chemical shifts for (1)H and (13)C NMR were calculated using gauge-invariant atomic orbital (GIAO) method. The experimental vibrational frequencies, (1)H and (13)C NMR chemical shift values were found to be in good agreement with the theoretical values. On the basis of vibrational analysis, molecular electrostatic potential and the standard thermodynamic functions have been investigated. PMID:25440584

Pasha, M A; Siddekha, Aisha; Mishra, Soni; Azzam, Sadeq Hamood Saleh; Umapathy, S

2015-02-01

196

A mass spectroscopic method for analysis of AHH-inducing and other polychlorinated biphenyl congeners and selected pesticides in fish  

USGS Publications Warehouse

The 209 polychlorinated biphenyl (PCB) congeners exhibit a wide range in toxicity to fish, birds, and mammals. This paper discusses the use of gas chromatography/mass spectrometry negative chemical ionization (GC/MS-NCI) to quantify congeners of highly suspected toxicity such as IUPAC #77 (3,3',4,4'-tetrachlorobiphenyl) and #126 (3,3',4,4',5-pentachlorobiphenyl). GC/MS analysis time needed to produce the necessary resolution was reduced to 1 h per sample or standard, allowing an autosampler to inject 12 samples in 24 hours, plus 12 standards/QC samples. Identification and quantification of some 60+ congeners and several selected pesticides and estimation of total PCBs are also possible within the 1 h analysis. For congeners of high chlorination (penta through octa), the method exhibited excellent sensitivity, such that we could not locate a fish which exhibited PCB levels below our calibrated quantitation range. NCI was not as sensitive for mono through tri and for some tetrachlorinated PCB congeners, an exception being PCB #77, for which sensitivity was of the same order as for the more highly chlorinated biphenyls. Long term stability was excellent. Over a 6-mo period, results of replicate analyses for PCB congeners and pesticides in a composited sample of lake trout (Salvelinus namaycush) from Lake Michigan had a relative standard deviation of 12% of the mean. Over the same time period, mean recoveries for samples spiked at concentrations similar to those in Lake Michigan lake trout were 90-102%. Response was linear over a wide range of concentrations for each of the analyzed compounds. This method is now being used for routine analysis of PCB congeners and selected pesticides in our laboratory.

Schmidt, Larry J.; Hesselberg, Robert J.

1992-01-01

197

Spectroscopic analysis of phase constitution of high quality VO2 thin film prepared by facile sol-gel method  

NASA Astrophysics Data System (ADS)

VO2 thin films with large-area were prepared on Al2O3 substrates by a simple sol-gel method. After an annealing treatment under low vacuum condition, all the VO2 films showed a preferred growth direction and exhibited excellent semiconductor-metal transition (SMT) characteristics. The structure and electrical properties of the obtained VO2 films were investigated systematically. Raman spectra, X-ray diffraction and X-ray absorption spectra measurements pointed out that the VO2 film on Al_2 O_3 ( {10overline 1 0}) substrate showed a M1 phase instead of M2 phase as reported in previous studies. Based on the experiment results, it was suggested that the strained structure of oriented VO2 films could be a mechanism for the formation of the intermediate M2 phase, whereas it is difficult to access the pure M2 phase of undoped VO2 films. VO2 film on Al_2 O_3 ( {10overline 1 0} ) substrate showed a lower SMT temperature compared to VO2 film on Al2O3 (0001), which can be mostly attributed to the differences of both lattice mismatch and thermal stress. The present results confirm and make clear the relevance of the substrate orientation in the growth of VO2 film and their different contributions to the SMT characteristics in vanadate systems.

Wu, Y. F.; Fan, L. L.; Chen, S. M.; Chen, S.; Zou, C. W.; Wu, Z. Y.

2013-04-01

198

Spectroscopic investigations on the synthesis of nano-hydroxyapatite from calcined eggshell by hydrothermal method using cationic surfactant as template.  

PubMed

The present work reports the successful synthesis of nano-hydroxyapatite, Ca(10)(PO(4))(6)(OH)(2) (denoted HAP) from calcined eggshell by hydrothermal method using cationic surfactant (CTAB) as regulator of nucleation and crystal growth. The reaction involved in the synthesis was studied elaborately. The influence of reaction temperature, ageing time and CTAB concentration on the synthesis of nano-HAP are also studied in addition to the effect of sintering temperature on the crystal growth. Spectral characterization involving Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were performed for functional group analysis and phase identification of the materials, respectively. Thermal stability of nano-HAP was investigated by thermal analysis (TG/DTA). The physical characteristics, such as morphology and particle size of the synthesized nano-HAP were assessed thoroughly by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The results have revealed that well-crystallized nano-HAP was synthesized by hydrothermal treatment at 160 degrees C for 10 h with the addition of CTAB at critical micelle concentration (CMC). It was also found that the synthesized nano-HAP was thermally stable up to 1100 degrees C. PMID:19836296

Prabakaran, K; Rajeswari, S

2009-12-01

199

Correlation mapping: rapid method for identification of histological features and pathological classification in mid infrared spectroscopic images of lymph nodes  

NASA Astrophysics Data System (ADS)

In this work, a novel technique for rapid image analysis of Fourier transform infrared (FTIR) data obtained from human lymph nodes is explored. It uses the mathematical principle of orthogonality as a method to quickly and efficiently obtain tissue and pathology information from a spectral image cube. It requires less computational power and time compared to most forms of cluster analysis. The values obtained from different tissue and pathology types allows for discrimination of noncancerous from cancerous lymph nodes. It involves the calculation of the dot product between reference spectra and individual spectra from across the tissue image. These provide a measure of the correlation between individual spectra and the reference spectra, and each spectrum or pixel in the image is given a color representing the reference most closely correlating with it. The correlation maps are validated with the tissue and pathology features identified by an expert pathologist from corresponding hematoxylin and eosin stained tissue sections. Although this novel technique requires further study to properly test and validate this tool, with inclusion of more lymph node hyperspectral datasets (containing a greater variety of tissue states), it demonstrates significant clinical potential for pathology diagnosis.

Isabelle, Martin; Rogers, Keith; Stone, Nicholas

2010-03-01

200

Investigation of trypsin-CdSe quantum dot interactions via spectroscopic methods and effects on enzymatic activity  

NASA Astrophysics Data System (ADS)

The paper presents the interactions between trypsin and water soluble cadmium selenide (CdSe) quantum dots investigated by spectrophotometric methods. CdSe quantum dots have strong ability to quench the intrinsic fluorescence of trypsin by a static quenching mechanism. The quenching has been studied at three different temperatures where the results revealed that electrostatic interactions exist between CdSe quantum dots and trypsin and are responsible to stabilize the complex. The Scatchard plot from quenching revealed 1 binding site for quantum dots by trypsin, the same has been confirmed by making isothermal titrations of quantum dots against trypsin. The distance between donor and acceptor for trypsin-CdSe quantum dot complexes is calculated to be 2.8 nm by energy transfer mechanisms. The intrinsic fluorescence of CdSe quantum dots has also been enhanced by the trypsin, and is linear for concentration of trypsin ranging 1-80 ?l. All the observations evidence the formation of trypsin-CdSe quantum dot conjugates, where trypsin retains the enzymatic activity which in turn is temperature and pH dependent.

Kaur, Gurvir; Tripathi, S. K.

2015-01-01

201

A noncalibration spectroscopic method to estimate ether extract and fatty acid digestibility of feed and its validation with flaxseed and field pea in pigs.  

PubMed

Digestibility of ether extract (EE) or fatty acids (FA) is traditionally measured by chemical analyses for EE or GLC methods for FA combined with marker concentration in diet and digesta or feces. Digestibility of EE or FA may be predicted by marker concentrations and spectral analyses of diet and digesta or feces. On the basis of Beer's law, a noncalibration spectroscopic method, which used functional group digestibility (FGD) determined with marker concentration and peak intensity of spectra of diets and undigested residues (digesta or feces), was developed to predict the apparent ileal digestibility (AID) of total FA and apparent total tract digestibility (ATTD) of EE. To validate, 4 diets containing 30% flaxseed and field pea coextruded with 4 extruder treatments and a wheat and soybean basal diet with predetermined AID of total FA and ATTD of EE were used. Samples of ingredients, diets, and freeze-dried digesta and feces were scanned on a Fourier transform infrared (FT-IR) instrument with a single-reflection attenuated total reflection (ATR) accessory. The intensity of either the methylene (CH2) antisymmetric stretching peak at 2,923 cm(-1) (R(2) = 0.90, P < 0.01) or the symmetric stretching peak at 2,852 cm(-1) (R(2) = 0.86, P < 0.01) of ingredients, diet, and digesta spectra was related strongly to the concentration of total FA. The AID of total FA of diets measured using GLC was predicted by the spectroscopic method using FGD at 2,923 and 2,852 cm(-1) (R(2) = 0.75, P < 0.01) with a bias of 0.54 (SD = 3.78%) and -1.35 (SD = 3.74%), respectively. The accumulated peak intensity in the region between 1,766 and 1,695 cm(-1) of spectra was related to EE concentration in ingredients and diets (R(2) = 0.61, P = 0.01) and feces (R(2) = 0.88, P < 0.01). The relation was improved by using second-derivative spectra of the sum of peak intensities at 1,743 and 1,710 cm(-1) for ingredients and diets (R(2) = 0.90, P = 0.01) and at 1,735 and 1,710 cm(-1) for feces (R(2) = 0.92, P < 0.01). The ATTD of EE of test diets determined with proximate analysis was estimated by the FGD of nonderivative spectra with or without baseline (R(2) = 0.90, P < 0.01) with a bias of 3.15 (SD = 3.14%) and 3.50 (SD = 3.24%), respectively. In conclusion, instead of using GLC methods or predictions based on calibrations, the AID of total FA and ATTD of EE can also be estimated directly from ATR FT-IR spectra, provided the ratio of marker in the diet and undigested residue is known. PMID:25186953

Wang, L F; Swift, M L; Zijlstra, R T

2014-10-01

202

Adsorption and conformation of serum albumin protein on gold nanoparticles investigated using dimensional measurements and in situ spectroscopic methods.  

PubMed

The adsorption and conformation of bovine serum albumin (BSA) on gold nanoparticles (AuNPs) were interrogated both qualitatively and quantitatively via complementary physicochemical characterization methods. Dynamic light scattering (DLS), asymmetric-flow field flow fractionation (AFFF), fluorescence spectrometry, and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy were combined to characterize BSA-AuNP conjugates under fluid conditions, while conjugates in the aerosol state were characterized by electrospray-differential mobility analysis (ES-DMA). The presence of unbound BSA molecules interferes with DLS analysis of the conjugates, particularly as the AuNP size decreases (i.e., below 30 nm in diameter). Under conditions where the ? value is high, where ? is defined as the ratio of scattering intensity by AuNPs to the scattering intensity by unbound BSA, DLS size results are consistent with results obtained after fractionation by AFFF. Additionally, the AuNP hydrodynamic size exhibits a greater proportional increase due to BSA conjugation at pH values below 2.5 compared with less acidic pH values (3.4-7.3), corresponding with the reversibly denatured (E or F form) conformation of BSA below pH 2.5. Over the pH range from 3.4 to 7.3, the hydrodynamic size of the conjugate is nearly constant, suggesting conformational stability over this range. Because of the difference in the measurement environment, a larger increase of AuNP size is observed following BSA conjugation when measured in the wet state (i.e., by DLS and AFFF) compared to the dry state (by ES-DMA). Molecular surface density for BSA is estimated based on ES-DMA and fluorescence measurements. Results from the two techniques are consistent and similar, but slightly higher for ES-DMA, with an average adsorbate density of 0.015 nm(-2). Moreover, from the change of particle size, we determine the extent of adsorption for BSA on AuNPs using DLS and ES-DMA at 21 °C, which show that increasing the concentration of BSA increases the measured change in AuNP size. Using ES-DMA, we observe that the BSA surface density reaches 90% of saturation at a solution phase concentration between 10 and 30 ?mol/L, which is roughly consistent with fluorescence and ATR-FTIR results. The equilibrium binding constant for BSA on AuNPs is calculated by applying the Langmuir equation, with resulting values ranging from 0.51 × 10(6) to 1.65 × 10(6) L/mol, suggesting a strong affinity due to bonding between the single free exterior thiol on N-form BSA (associated with a cysteine residue) and the AuNP surface. Moreover, the adsorption interaction induces a conformational change in BSA secondary structure, resulting in less ?-helix content and more open structures (?-sheet, random, or expanded). PMID:21341776

Tsai, De-Hao; DelRio, Frank W; Keene, Athena M; Tyner, Katherine M; MacCuspie, Robert I; Cho, Tae Joon; Zachariah, Michael R; Hackley, Vincent A

2011-03-15

203

Disjunctive Kriging: 2. Examples  

NASA Astrophysics Data System (ADS)

The disjunctive kriging (DK) method described in detail in the previous paper of this series is illustrated by two examples. The first example is for the electrical conductivity (EC) which is approximately lognormally distributed. In the second example the natural logarithm of the EC is used to produce an approximately normally distributed data set. The data set was chosen since the Hermite coefficients for a normal and lognormal distribution could be determined analytically as well as to facilitate a comparison between ordinary and disjunctive kriging. The capability of DK to be a nonlinear estimator and an estimator of the conditional probability is explored. The results indicate that DK is a better estimator than linear estimators (i.e., ordinary kriging) in the sense of reduced variance of errors and average kriging variance even when the data are approximately normally or lognormally distributed. Also, using DK one can obtain an estimate of the conditional probability.

Yates, S. R.; Warrick, A. W.; Myers, D. E.

1986-05-01

204

Deciphering P-T paths in metamorphic rocks involving zoned minerals using quantified maps (XMapTools software) and thermodynamics methods: Examples from the Alps and the Himalaya.  

NASA Astrophysics Data System (ADS)

Metamorphic rocks are made by mosaic of local thermodynamic equilibria involving minerals that grew at different temporal, pressure (P) and temperature (T) conditions. These local (in space but also in time) equilibria can be identified using micro-structural and textural criteria, but also tested using multi-equilibrium techniques. However, linking deformation with metamorphic conditions requires spatially continuous estimates of P and T conditions in least two dimensions (P-T maps), which can be superimposed to the observed structures of deformation. To this end, we have developed a new Matlab-based GUI software for microprobe X-ray map processing (XMapTools, http://www.xmaptools.com) based on the quantification method of De Andrade et al. (2006). XMapTools software includes functions for quantification processing, two chemical modules (Chem2D, Triplot3D), the structural formula functions for common minerals, and more than 50 empirical and semi-empirical geothermobarometers obtained from the literature. XMapTools software can be easily coupled with multi-equilibrium thermobarometric calculations. We will present examples of application for two natural cases involving zoned minerals. The first example is a low-grade metapelite from the paleo-subduction wedge in the Western Alps (Schistes Lustrés unit) that contains only both zoned chlorite and phengite, and also quartz. The second sample is a Himalayan eclogite from the high-pressure unit of Stak (Pakistan) with an eclogitic garnet-omphacite assemblage retrogressed into clinopyroxene-plagioclase-amphibole symplectite, and later into amphibole-biotite during the collisional event under crustal conditions. In both samples, P-T paths were recovered using multi-equilibrium, or semi-empirical geothermobarometers included in the XMapTools package. The results will be compared and discussed with pseudosections calculated with the sample bulk composition and with different local bulk rock compositions estimated with XMapTools. De Andrade, V., Vidal, O., Lewin, E., O'Brien, P., Agard, P., 2006. Quantification of electron microprobe compositional maps of rock thin sections: an optimized method and examples. Journal of Metamorphic Geology 24, 655-668.

Lanari, P.; Vidal, O.; Schwartz, S.; Riel, N.; Guillot, S.; Lewin, E.

2012-04-01

205

[Advanced imaging methods as a basis for more reliable classification and better treatment for patients with depressive symptoms--an example for conceptual change in the psychiatric diagnostic method].  

PubMed

The current editorial study focuses on the idea of using advanced imaging methods in order to better classify and treat patients with depression and other psychiatric illnesses. The editorial is based on the review of Heymann and Bonne, published in this issue of the journal, showing differences between bi-polar and uni-polar depression using functional neuroimaging methods. This example, although not applicable yet in clinical practice, is the basis for future advances in psychiatric classification, together with clinical subtyping, and more biological markers, including genetic profiling. PMID:22111122

Vishne, Tali

2011-10-01

206

Examples of quantum integrals  

NASA Astrophysics Data System (ADS)

We first consider a method of centering and a change of variable formula for a quantum integral. We then present three types of quantum integrals. The first considers the expectation of the number of heads in n flips of a "quantum coin". The next computes quantum integrals for destructive pairs examples. The last computes quantum integrals for a (Lebesgue) 2 quantum measure. For this last type we prove some quantum counterparts of the fundamental theorem of calculus.

Gudder, Stan

2010-08-01

207

A generalized series approach to MR spectroscopic imaging  

Microsoft Academic Search

The problem of precise spatial localization of spectral information in magnetic resonance (MR) spectroscopic imaging is addressed. A novel method, called GSLIM (generalized spectral location by imaging), is proposed to make possible the marriage of high-resolution proton imaging with spectroscopic imaging and localization. This method improves on the conventional Fourier series inversion method used in chemical shift imaging (CSI) and

Zhi-Pei Liang; Paul C. Lauterbur

1991-01-01

208

Evaluation of Polycyclic Aromatic Hydrocarbons Using Analytical Methods, Toxicology, and Risk Assessment Research: Seafood Safety after a Petroleum Spill as an Example  

PubMed Central

Background: Polycyclic aromatic hydrocarbons (PAHs) are abundant and widespread environmental chemicals. They are produced naturally and through man-made processes, and they are common in organic media, including petroleum. Several PAHs are toxic, and a subset exhibit carcinogenic activity. PAHs represent a range of chemical structures based on two or more benzene rings and, depending on their source, can exhibit a variety of side modifications resulting from oxygenation, nitrogenation, and alkylation. Objectives: Here we discuss the increasing ability of contemporary analytical methods to distinguish not only different chemical structures among PAHs but also their concentrations in environmental media. Using seafood contamination following the Deepwater Horizon accident as an example, we identify issues that are emerging in the PAH risk assessment process because of increasing analytical sensitivity for individual PAHs, and we describe the paucity of toxicological literature for many of these compounds. Discussion: PAHs, including the large variety of chemically modified or substituted PAHs, are naturally occurring and may constitute health risks if human populations are exposed to hazardous levels. However, toxicity evaluations have not kept pace with modern analytic methods and their increased ability to detect substituted PAHs. Therefore, although it is possible to measure these compounds in seafood and other media, we do not have sufficient information on the potential toxicity of these compounds to incorporate them into human health risk assessments and characterizations. Conclusions: Future research efforts should strategically attempt to fill this toxicological knowledge gap so human health risk assessments of PAHs in environmental media or food can be better determined. This is especially important in the aftermath of petroleum spills. Citation: Wickliffe J, Overton E, Frickel S, Howard J, Wilson M, Simon B, Echsner S, Nguyen D, Gauthe D, Blake D, Miller C, Elferink C, Ansari S, Fernando H, Trapido E, Kane A. 2014. Evaluation of polycyclic aromatic hydrocarbons using analytical methods, toxicology, and risk assessment research: seafood safety after a petroleum spill as an example. Environ Health Perspect 122:6–9;?http://dx.doi.org/10.1289/ehp.1306724 PMID:24213154

Overton, Edward; Frickel, Scott; Howard, Jessi; Wilson, Mark; Simon, Bridget; Echsner, Stephen; Nguyen, Daniel; Gauthe, David; Blake, Diane; Miller, Charles; Elferink, Cornelis; Ansari, Shakeel; Fernando, Harshica; Trapido, Edward; Kane, Andrew

2013-01-01

209

Spectroscopic Detection of Pathogens  

SciTech Connect

The goal of this LDRD Research project was to provide a preliminary examination of the use of infrared spectroscopy as a tool to detect the changes in cell cultures upon activation by an infectious agent. Due to a late arrival of funding, only 5 months were available to transfer and setup equipment at UTTM,develop cell culture lines, test methods of in-situ activation and collect kinetic data from activated cells. Using attenuated total reflectance (ATR) as a sampling method, live cell cultures were examined prior to and after activation. Spectroscopic data were collected from cells immediately after activation in situ and, in many cases for five successive hours. Additional data were collected from cells activated within a test tube (pre-activated), in both transmission mode as well as in ATR mode. Changes in the infrared data were apparent in the transmission data collected from the pre-activated cells as well in some of the pre-activated ATR data. Changes in the in-situ activated spectral data were only occasionally present due to (1) the limited time cells were studied and (2) incomplete activation. Comparison of preliminary data to infrared bands reported in the literature suggests the primary changes seen are due an increase in ribonucleic acid (RNA) production. This work will be continued as part of a 3 year DARPA grant.

ALAM,M. KATHLEEN; TIMLIN,JERILYN A.; MARTIN,LAURA E.; HJELLE,DRIAN; LYONS,RICK; GARRISON,KRISTIN

2000-11-01

210

Use of new field methods of semen analysis in the study of occupational hazards to reproduction: the example of ethylene dibromide  

SciTech Connect

Increasing attention has been paid to the use of semen analysis as an indicator of exposure to potential mutagenic and reproductive hazards. In the infertility clinic setting, semen evaluations include the measurement of sperm concentration, volume, pH, motility, velocity and morphology, the analysis of seminal plasma to evaluate accessory sex gland function and, in some cases, the in vitro evaluation of fertilization capacity and sperm-cervical mucus interaction. To date, however, the study of semen characteristics of occupationally exposed populations has been confined principally to the measurement of sperm concentration and sperm morphology. This has been largely due to the unavailability of portable equipment suitable for the measurement of other semen characteristics and the difficulty of obtaining fresh semen samples in the field setting. National Institute for Occupational Safety and Health researchers have developed mobile laboratory facilities which enable us to evaluate fresh samples, in the field, for semen characteristics in addition to concentration and morphology. This paper describes the application of these methods using the example of our recent cross-sectional study of workers occupationally exposed to ethylene dibromide in the papaya fumigation industry. We discuss our findings in the context of the usefulness of semen analysis as an indicator of occupational hazards to male reproduction.

Schrader, S.M.; Ratcliffe, J.M.; Turner, T.W.; Hornung, R.W.

1987-12-01

211

Spectroscopic full polarimeters using spatial carriers  

NASA Astrophysics Data System (ADS)

Several implementations of spectroscopic polarimeters using spatial carriers are presented. The first implementation incorporates two Savart plates and a spectrometer including a two-dimensional CCD to generate a spectrum with spatial carriers. The frequency filtering along the spatial coordinate at each wavelength allows us to conduct the snapshot measurement of the wavelength-resolved Stokes parameters. The spectral resolution of the SOP measurement can be enhanced up to that of the spectrometer. In the second implementation, two achromatic birefringent prism pairs are used to decrease the limitation in the design of the spectroscopic polarimeter. Finally, the present method is combined with a channeled spectroscopic polarization state generator so that the spectroscopic Mueller matrix of a sample can be determined by the snapshot measurement of the two-dimensional spectrum.

Oka, Kazuhiko; Haga, Yujin; Komaki, Yoshihiko

2013-09-01

212

Spectroscopic signatures of isomnerization  

E-print Network

This thesis explores spectroscopic signatures of isomerization, especially new patterns that emerge and report on chemically relevant portions of the potential energy surface, such as the transition state. The most important ...

Baraban, Joshua Herschel Goldblum

2013-01-01

213

The WFI Halpha spectroscopic survey  

E-print Network

This document presents the results from our spectroscopic survey of Halpha emitters in galactic and SMC open clusters with the ESO Wide Field Imager in its slitless spectroscopic mode. First of all, for the galactic open cluster NGC6611, in which, the number and the nature of emission line stars is still the object of debates, we show that the number of true circumstellar emission line stars is small. Second, at low metallicity, typically in the Small Magellanic Cloud, B-type stars rotate faster than in the Milky Way and thus it is expected a larger number of Be stars. However, till now, search for Be stars was only performed in a very small number of open clusters in the Magellanic Clouds. Using the ESO/WFI in its slitless spectroscopic mode, we performed a Halpha survey of the Small Magellanic Cloud. 3 million low-resolution spectra centered on Halpha were obtained in the whole SMC. Here, we present the method to exploit the data and first results for 84 open clusters in the SMC about the ratios of Be stars to B stars.

Christophe Martayan; Dietrich Baade; Juan Fabregat

2008-09-25

214

Discussion about decision support systems using continuous multi-criteria methods for planning in areas with hydro-basins, agriculture and forests, from examples in Argentine.  

NASA Astrophysics Data System (ADS)

The authors were involved last years in projects considering diverse decision problems on the use of some regions in Argentine, and also related to rivers or rural services in them. They used sets of multi-criteria decision methods, first discrete when the problem included few distinct alternatives, such as e.g. forestry, traditional or intensive agriculture. For attributes they were different effects, classified then in environmental, economic and social criteria. Extending to other gentler areas, such as at South of the Province of Córdoba, Arg., they have balanced more delicately effects of continuous levels of actions, with a combination of Goal Programming linked methods, and they adopted compromises to have precise solutions. That has shown, and in part open, a line of research, as the setting of such models require various kinds of definitions and valuations, including optimizations, goals with penalties in deviations and restrictions. That can be in diverse detail level and horizon, in presence of various technical and human horizons, and that can influence politics of use of terrain and production that will require public and private agents. The research will consider consideration of use and conservation of soils, human systems and agro productions, and hence models for optimization, preferably in such Goal Programming ways. That will require considering various systems of models, first in theory to be reliable, and then in different areas to evaluate the quality of conclusions, and maybe that successively if results are found advantageous. The Bayesian ways will be considered, but they would require a prospective of sets of precise future states of nature or markets with elicited probabilities, which are neither evident nor decisive for the moment, as changes may occur in years but will be very unexpected or uncertain. The results will be lines of models to aid to establish policies of use of territories, by public agencies setting frames for private agents of different size and kinds, with different horizons of climatic and human changes. The usable models will depend somehow on the type of areas, which have different climates and soils, population, markets and maybe civilizations, starting with Argentine examples, if possible compared in cases with Spain.

Anton, J. M.; Grau, J. B.; Tarquis, A. M.; Andina, D.; Cisneros, J. M.; Sanchez, E.

2012-04-01

215

REVIEW OF SCIENTIFIC INSTRUMENTS 84, 023507 (2013) Development of a polarization resolved spectroscopic diagnostic for  

E-print Network

spectroscopic diagnostic for measurements of the vector magnetic field in the Caltech coaxial magnetized plasma-perturbing visible emission spectroscopic method is implemented to observe the Zeeman splitting in emission spectra strength in the ex- periment, a non-perturbing spectroscopic method was imple- mented to observe the Zeeman

Bellan, Paul M.

216

A Spectroscopic-Based Laboratory Experiment for Protein Conformational Studies  

ERIC Educational Resources Information Center

This article describes a practical experiment for teaching basic spectroscopic techniques to introduce the topic of protein conformational change to students in the field of molecular biology, biochemistry, or structural biology. The spectroscopic methods employed in the experiment are absorbance, for protein concentration measurements, and…

Ramos, Carlos Henrique I.

2004-01-01

217

The Origin, Composition and History of Comets from Spectroscopic Studies  

NASA Technical Reports Server (NTRS)

A wealth of information essential to understanding the composition and physical structure of cometary ice and hence gain deep insight into the comet's origin and history, can be gleaned by carrying out a full range of spectroscopic studies on the returned sample. These studies ought to be among the first performed as they are generally non-destructive and will provide a broad data bank which will be crucial in planning subsequent analysis. Examples of the spectroscopic techniques along with relative sensitivities and transitions probed, are discussed. Different kind of "spectroscopy" is summarized, with emphasis placed on the kind of information each provides. Infrared spectroscopy should be the premier method of analysis as the mid-IR absorption spectrum of a substance contains more global information about the identity and structure of that material than any other property. In fact, the greatest strides in our understanding of the composition of interstellar ices (thought by many to be the primordial material from which comets have formed) have been taken during the past ten years or so because this was when high quality infrared spectra of the interstellar medium (ISM) first became available. The interpretation of the infrared spectra of mixtures, such as expected in comets, is often (not always) ambiguous. Consequently, a full range of other non-destructive, complementary spectroscopic measurements are required to fully characterize the material, to probe for substances for which the IR is not well suited and to lay the groundwork for future analysis. Given the likelihood that the icy component (including some of the organic and mineral phases) of the returned sample will be exceedingly complex, these techniques must be intensely developed over the next decade and then made ready to apply flawlessly to what will certainly be one of the most precious, and most challenging, samples ever analyzed.

Allamandola, L. J.

1997-01-01

218

Lensing Probabilities for Spectroscopically Selected Galaxy-Galaxy Strong Lenses  

E-print Network

Spectroscopic galaxy-galaxy lens searches are presently the most prolific method of identifying strong lens systems in large data sets. We study the probabilities associated with these lens searches, namely the probability of identifying a candidate with rogue [OII] emission lines in a galaxy's spectrum, and the probability that the candidate will show features of strong lensing in follow-up photometric observations. We include selection effects unique to spectroscopic data, and apply them to the Sloan Lens ACS (SLACS) survey (Bolton et al. 2006). The most significant selection effect is the finite size of the spectroscopic fiber which selects against large separation lenses and results in a non-monotonic dependence of the rogue line probability on velocity dispersion. For example, with the 3 arcsec diameter SDSS fiber and 2 arcsec FWHM seeing, we find that the probability that a given LRG has a rogue [OII] line in its spectrum decreases with velocity dispersion from 150 km/s to 300 km/s and then increases up to 400 km/s for a given source size. The total probability for observing a rogue line in a single survey spectrum is ~0.9-3.0%, and the total lensing rate is ~0.5-1.3%. The range is due to uncertainties in the physical size of [OII] emission regions, and in the evolution of the [OII] luminosity function. Our estimates are a factor of ~5 higher than the results of the SLACS survey, a discrepancy which we attribute to the SLACS requirement that multiple rogue lines be observed simultaneously.

Gregory Dobler; Charles R. Keeton; Adam S. Bolton; Scott Burles

2008-03-17

219

Example based lesion segmentation  

NASA Astrophysics Data System (ADS)

Automatic and accurate detection of white matter lesions is a significant step toward understanding the progression of many diseases, like Alzheimer's disease or multiple sclerosis. Multi-modal MR images are often used to segment T2 white matter lesions that can represent regions of demyelination or ischemia. Some automated lesion segmentation methods describe the lesion intensities using generative models, and then classify the lesions with some combination of heuristics and cost minimization. In contrast, we propose a patch-based method, in which lesions are found using examples from an atlas containing multi-modal MR images and corresponding manual delineations of lesions. Patches from subject MR images are matched to patches from the atlas and lesion memberships are found based on patch similarity weights. We experiment on 43 subjects with MS, whose scans show various levels of lesion-load. We demonstrate significant improvement in Dice coefficient and total lesion volume compared to a state of the art model-based lesion segmentation method, indicating more accurate delineation of lesions.

Roy, Snehashis; He, Qing; Carass, Aaron; Jog, Amod; Cuzzocreo, Jennifer L.; Reich, Daniel S.; Prince, Jerry; Pham, Dzung

2014-03-01

220

Application of correlation constrained multivariate curve resolution alternating least-squares methods for determination of compounds of interest in biodiesel blends using NIR and UV-visible spectroscopic data.  

PubMed

This study describes two applications of a variant of the multivariate curve resolution alternating least squares (MCR-ALS) method with a correlation constraint. The first application describes the use of MCR-ALS for the determination of biodiesel concentrations in biodiesel blends using near infrared (NIR) spectroscopic data. In the second application, the proposed method allowed the determination of the synthetic antioxidant N,N'-Di-sec-butyl-p-phenylenediamine (PDA) present in biodiesel mixtures from different vegetable sources using UV-visible spectroscopy. Well established multivariate regression algorithm, partial least squares (PLS), were calculated for comparison of the quantification performance in the models developed in both applications. The correlation constraint has been adapted to handle the presence of batch-to-batch matrix effects due to ageing effects, which might occur when different groups of samples were used to build a calibration model in the first application. Different data set configurations and diverse modes of application of the correlation constraint are explored and guidelines are given to cope with different type of analytical problems, such as the correction of matrix effects among biodiesel samples, where MCR-ALS outperformed PLS reducing the relative error of prediction RE (%) from 9.82% to 4.85% in the first application, or the determination of minor compound with overlapped weak spectroscopic signals, where MCR-ALS gave higher (RE (%)=3.16%) for prediction of PDA compared to PLS (RE (%)=1.99%), but with the advantage of recovering the related pure spectral profile of analytes and interferences. The obtained results show the potential of the MCR-ALS method with correlation constraint to be adapted to diverse data set configurations and analytical problems related to the determination of biodiesel mixtures and added compounds therein. PMID:24840439

de Oliveira, Rodrigo Rocha; de Lima, Kássio Michell Gomes; Tauler, Romà; de Juan, Anna

2014-07-01

221

How specific Raman spectroscopic models are: a comparative study between different cancers  

NASA Astrophysics Data System (ADS)

Optical spectroscopic methods are being contemplated as adjunct/ alternative to existing 'Gold standard' of cancer diagnosis, histopathological examination. Several groups are actively pursuing diagnostic applications of Ramanspectroscopy in cancers. We have developed Raman spectroscopic models for diagnosis of breast, oral, stomach, colon and larynx cancers. So far, specificity and applicability of spectral- models has been limited to particular tissue origin. In this study we have evaluated explicitly of spectroscopic-models by analyzing spectra from already developed spectralmodels representing normal and malignant tissues of breast (46), cervix (52), colon (25), larynx (53), and oral (47). Spectral data was analyzed by Principal Component Analysis (PCA) using scores of factor, Mahalanobis distance and Spectral residuals as discriminating parameters. Multiparametric limit test approach was also explored. The preliminary unsupervised PCA of pooled data indicates that normal tissue types were always exclusive from their malignant counterparts. But when we consider tissue of different origin, large overlap among clusters was found. Supervised analysis by Mahalanobis distance and spectral residuals gave similar results. The 'limit test' approach where classification is based on match / mis-match of the given spectrum against all the available spectra has revealed that spectral models are very exclusive and specific. For example breast normal spectral model show matches only with breast normal spectra and mismatch to rest of the spectra. Same pattern was seen for most of spectral models. Therefore, results of the study indicate the exclusiveness and efficacy of Raman spectroscopic-models. Prospectively, these findings might open new application of Raman spectroscopic models in identifying a tumor as primary or metastatic.

Singh, S. P.; Kumar, K. Kalyan; Chowdary, M. V. P.; Maheedhar, K.; Krishna, C. Murali

2010-02-01

222

Control of lightness and firmness of cold and reheated frankfurter-type sausages using different spectroscopic methods applied to raw batter.  

PubMed

Muscle types and collagen, fat, and muscle protein minus collagen were varied in cooked frankfurter-type sausages made from beef and pork meat as well as pork backfat. The content of collagen was fixed at preset levels with pork rind. The amount of total muscle protein in the sausages varied between 5.9% and 11.9% and the fat between 16.1% and 22.1%. The collagen content varied between 1.3% and 4%. Spectroscopic measurements (near-infrared reflectance spectra 1100 to 2500 nm; front-face autofluorescence emission spectra 360 to 640 nm) on raw batters were used to predict the amounts of total muscle protein minus collagen, collagen, myoglobin, and fat (biochemical components), L* values from a Minolta chromameter, and firmness of cold (22 degrees C) and reheated sausages (60 degrees C). Lightness of sausages was most accurately determined from the batter data with a Minolta chromameter or the autofluorescence measurement system. Firmness of cold sausages could be described by the amounts of biochemical components plus the type of muscle used in the sausage. The 2nd-best approach was to use the shape of the near-infrared spectra to determine firmness. This was possible as the shape of near-infrared spectra depended on total protein content, and total protein content largely determined the firmness of cold sausages. If the sausages were reheated to 60 degrees C, near-infrared spectroscopy alone determined firmness of the sausages with a lower accuracy than a combined solution of fluorescence and near-infrared spectroscopy. The 2 spectroscopic techniques could thus be used to estimate the amount of biochemical components in sausages. Once these components were known, firmness could be calculated from a model between the amounts of biochemical components and firmness. For reheated sausages, as opposed to cold ones, there was a need to differentiate between collagen and the other muscle proteins in order to determine firmness. This was optimally achieved by using both autofluorescence and near-infrared spectroscopy. PMID:17995835

Egelandsdal, B; Dingstad, G I; Tøgersen, G; Hildrum, K I

2007-03-01

223

Spectroscopic Surveys: Present  

E-print Network

I summarize the current spectroscopic sky surveys and some of the scientific results, emphasizing the largest sky survey to-date, the Sloan Digital Sky Survey (SDSS). Techniques used commonly in spectral analyses are discussed, followed by the present needs and challenges for solving some of the unknown problems. I discuss how the Virtual Observatory (VO) can help astronomers in carrying out related research.

Ching-Wa Yip

2007-06-29

224

Laser/Spectroscopic Determination Of Mass Flows  

NASA Technical Reports Server (NTRS)

Mass flow rates of air and other gases computed from absorption-spectroscopic measurements of light generated by tunable diode lasers. Rates of flow measured nonintrusively. Method implemented with rugged, compact, economical lasers and optical fibers to guide laser light to and from measurement locations.

Hanson, R. K.

1994-01-01

225

A comparative study of caffeine and theophylline binding to Mg(II) and Ca(II) ions: studied by FTIR and UV spectroscopic methods  

NASA Astrophysics Data System (ADS)

The interactions of calcium and magnesium ions with caffeine and theophylline have been investigated in aqueous solution at physiological pH. Fourier Transform infrared (FTIR) spectroscopy and absorption spectra were used to determine the cation binding mode and the association constants. Our spectroscopic results showed that calcium and magnesium ions do not complex with caffeine strongly and the weak interactions between caffeine and Mg 2+ and Ca 2+ might be via O6 atom. In Ca 2+-theophylline complex, binding between Ca 2+ with C?O and N7 is observed, however in Mg 2+-theophylline complex, binding between Mg 2+ and N7 is more likely. The k values of these complexes are as follows: k(caffeine-Ca)=29.8 M -1, k(caffeine-Mg)=22.4 M -1, k(theophylline-Ca)=59.8 M -1 and k(theophylline-Mg)=33.8 M -1. These values are evidence for a weak cation interaction in these metal complexes.

Nafisi, Shohreh; Shamloo, Delaram Sadraii; Mohajerani, Nasser; Omidi, Akram

2002-08-01

226

FT-IR, FT-Raman, dispersive Raman, NMR spectroscopic studies and NBO analysis of 2-Bromo-1H-Benzimidazol by density functional method  

NASA Astrophysics Data System (ADS)

In this study, geometrical optimization, FT-IR (4000-400 cm-1), FT-Raman (4000-40 cm-1), dispersive Raman (4000-40 cm-1) spectroscopic analysis, electronic structure and 1H and 13C nuclear magnetic resonance (NMR) studies of 2-Bromo-1H-Benzimidazol (abbreviated as 2Br1HB) were undertaken by utilizing DFT/B3LYP with 6-311+G(d,p) basis set. The results of the calculations were applied to simulate spectra of the title compound, which show good agreement with observed spectra. Complete vibrational assignments, analysis and correlations of the fundamental modes for 2Br1HB compound were carried out. Stability of the molecule arising from hyperconjugative interactions, charge delocalization was analyzed using natural bond orbital (NBO) analysis. The molecule orbital contributions were studied by using the total density of states (TDOS), partial density of states (PDOS), and overlap population density of states (OPDOS). The electronic properties like HOMO-LUMO energies and molecular electrostatic potential (MEP) analysis were reported. The calculated HOMO and LUMO energies shows that charge transfer interactions take place within the molecule. Mulliken population analysis on atomic charges was also calculated. Good correlation between the experimental 1H and 13C NMR chemical shifts in DMSO solution and calculated gauge-including atomic orbital (GIAO) shielding tensors were found.

Sas, E. B.; Kurt, M.; Karabacak, M.; Poiyamozhi, A.; Sundaraganesan, N.

2015-02-01

227

Study on the interaction between methyl jasmonate and the coiled-coil domain of rice blast resistance protein Pi36 by spectroscopic methods.  

PubMed

Interaction between the coiled-coil domain of rice blast resistance protein Pi36 and methyl-jasmonate (MeJA) was studied by fluorescence and UV-vis spectroscopic techniques. The quenching mechanism of fluorescence of MeJA by this domain was discussed to be a static quenching procedure. Fluorescence quenching was explored to measure the number of binding sites n and apparent binding constants K. The thermodynamics parameters ?H, ?G, ?S were also calculated. The results indicate the binding reaction was not entropy-driven but enthalpy-driven, and hydrophobic binding played major role in the interaction. The binding sites of MeJA with the coiled-coil structural domain of rice blast resistance protein Pi36 were found to approach the microenvironment of both Tyr and Trp by the synchronous fluorescence spectrometry. The distance r between donor (the coiled-coil domain of rice blast resistance protein Pi36) and acceptor (MeJA) was obtained according to Förster theory of non-radioactive energy transfer. PMID:22196797

Liu, Xin Q; Zhang, Dan; Zhang, Xiang M; Wang, Chun T; Liu, Xue Q; Tan, Yan P; Wu, Yun H

2012-03-01

228

An example of using a decision making framework designed for non-medical prescribers as a method for enhancing prescribing safety for inhaled corticosteroids (ICS)  

PubMed Central

Non-medical prescribing is needed especially with the increased demand for health care and the physicians’ time constrains. Also, it is not well regulated in Saudi Arabia unlike the United Kingdom. This report aims to demonstrate the urged need for regulations to maintain a safe non-medical prescribing process. It also adapts the single competency framework provided by the United Kingdom national prescribing centre (NPC, 2012) to be utilised by the respiratory therapist for a safe prescribing process for inhaled corticosteroids (ICS) to control adult asthma as an example. The framework is thought to be an effective tool for safe non-medical prescribing and it is highly recommended to develop a national Saudi framework to maintain the patients’ safety and utilise resources.

Almarshad, Saja

2014-01-01

229

Spectroscopic study of solar twins and analogues  

E-print Network

Context. Many large stellar surveys have been and are still being carried out, providing huge amounts of data, for which stellar physical parameters will be derived. Solar twins and analogues provide a means to test the calibration of these stellar catalogues because the Sun is the best-studied star and provides precise fundamental parameters. Solar twins should be centred on the solar values. Aims. This spectroscopic study of solar analogues selected from the Geneva-Copenhagen Survey (GCS) at a resolution of 48,000 provides effective temperatures and metallicities for these stars. We test whether our spectroscopic parameters, as well as the previous photometric calibrations, are properly centred on the Sun. In addition, we search for more solar twins in our sample. Methods. The methods used in this work are based on literature methods for solar twin searches and on methods we developed in previous work to distinguish the metallicity-temperature degeneracies in the differential comparison of spectra of solar ...

Datson, Juliet; Portinari, Laura

2014-01-01

230

Optimization of a simple field method to determine mercury volatilization from soils—Examples of 13 sites in floodplain ecosystems at the Elbe River (Germany)  

Microsoft Academic Search

Mercury fluxes between soil and atmosphere have often been determined by using dynamic flux chambers and micrometeorological methods to assess ecological risks. However, both systems are complex, stationary, and expensive impeding measurements of Hg emissions at various field sites.The mobile, easy to handle, and cost-effective field method to determine total gaseous mercury (TGM), according to [Böhme, F., Rinklebe, J., Stärk,

Jörg Rinklebe; Mark Overesch; Rainer Wennrich; Hans-Joachim Stärk; Sibylle Mothes; Heinz-Ulrich Neue

2009-01-01

231

Electromagnetic and geochemical methods applied to investigations of hydrothermal\\/volcanic unrests: Examples of Taal (Philippines) and Miyake-jima (Japan) volcanoes  

Microsoft Academic Search

Magnetic, -electric and -electromagnetic phenomena (EM) are almost always observed on volcanoes before and during volcanic eruptions, if EM methods are well-designed and applied on the field. But unfortunately these methods are, most often, still used independently. They also do not benefit of dense inter-correlated networks which should allow more accurate results and fine modelling of the volcanic activity. On

Jacques Zlotnicki; Y. Sasai; J. P. Toutain; E. Villacorte; M. Harada; P. Yvetot; F. Fauquet; A. Bernard; T. Nagao

2009-01-01

232

Electromagnetic and geochemical methods applied to investigations of hydrothermal\\/volcanic unrests: Examples of Taal (Philippines) and Miyake-jima (Japan) volcanoes  

Microsoft Academic Search

Magnetic, -electric and -electromagnetic phenomena (EM) are almost always observed on volcanoes before and during volcanic eruptions, if EM methods are well-designed and applied on the field. But unfortunately these methods are, most often, still used independently. They also do not benefit of dense inter-correlated networks which should allow more accurate results and fine modelling of the volcanic activity. On

Jacques Zlotnicki; Y. Sasai; E. Villacorte; M. Harada; P. Yvetot; F. Fauquet; A. Bernard; T. Nagao

2008-01-01

233

Use of Spectroscopic Representations in Student?Generated Atomic Models  

Microsoft Academic Search

The goal of this paper is to illustrate college students' levels of sophistication of their spectroscopic representations (SRs). For example, a photon is drawn as a wavy line, which might be used to enhance their atomic models (AMs). Study 1 was a quantitative study in which 70 students, enrolled in first semester general chemistry, drew or described their own model

Jerry P. Suits; Karen L. Hypolite

2004-01-01

234

Delta Function Potential Example  

NSDL National Science Digital Library

This website contains a detailed development of "motion" in a square well potential, complete with figures. This example is a part of a larger collection of examples in which the classical and quantum mechanical descriptions are compared. (Note that there are multiple pages, and that the user must use the navigation buttons at the bottom of the page)

Kirkman, Tom

2005-07-26

235

Spectroscopic Mode Identification in Slowly Pulsating Subdwarf-B Stars  

E-print Network

Mode identification is crucial for an asteroseismological study of any significance. Contrarily to spectroscopic techniques, methods such as period-fitting and multi-colour photometry do not provide a full reconstruction of non-radial pulsations. We present a new method of spectroscopic mode identification and test it on time-series of synthetic spectra appropriate for pulsating subdwarf-B stars. We then apply it to the newly discovered slowly pulsating subdwarf-B star HD 4539.

C. Schoenaers; A. E. Lynas-Gray

2008-04-28

236

Spectroscopic Properties and Potential Energy Curves of SnF +  

NASA Astrophysics Data System (ADS)

Spectroscopic properties and potential energy curves of several electronic states of SnF + are computed using the complete active space self-consistent field (CASSCF) followed by first- and second-order configuration interaction (FOCI, SOCI) methods that include up to 1.6 million configurations. Spin-orbit effects were incorporated using the relativistic configuration interaction (RCI) method. Spectroscopic properties of several excited electronic states of SnF + are reported, none of which is observed at present.

Balasubramanian, K.; Xu, H.

1995-06-01

237

Comparison of a new GIS-based technique and a manual method for determining sinkhole density: An example from Illinois' sinkhole plain  

USGS Publications Warehouse

A new Geographic Information System (GIS) method was developed as an alternative to the hand-counting of sinkholes on topographic maps for density and distribution studies. Sinkhole counts were prepared by hand and compared to those generated from USGS DLG data using ArcView 3.2 and the ArcInfo Workstation component of ArcGIS 8.1 software. The study area for this investigation, chosen for its great density of sinkholes, included the 42 public land survey sections that reside entirely within the Renault Quadrangle in southwestern Illinois. Differences between the sinkhole counts derived from the two methods for the Renault Quadrangle study area were negligible. Although the initial development and refinement of the GIS method required considerably more time than counting sinkholes by hand, the flexibility of the GIS method is expected to provide significant long-term benefits and time savings when mapping larger areas and expanding research efforts. ?? 2004 by The National Speleological Society.

Angel, J.C.; Nelson, D.O.; Panno, S.V.

2004-01-01

238

An improved "hand calculation" technique for analyzing pressure build-up data from low permeability, vertically fractured gas wells-camparison to other methods using field examples  

E-print Network

e 36 37 Comprehens1ve Graph of Normalized Fracture Length from all Methods Studied vs. Fracture Length from the History Match 39 15 16 17 Normalized Fracture Conductivity as Obtained from the Modified M-C Method vs. Fracture Conduct1vity... from the History Match 40 Normalized Fracture Conductiv ty as Obtained from the Iterat1ve Scheme vs. Fracture Conduct1vity from the History Match . . . . . . . . . . . . . . . . . . . , . . . , . . 41 Comprehensive Graph of Normalized Fracture...

McGee, James Herman

2012-06-07

239

Singlet and Triplet Excited States of Emissive, Conjugated Bis(porphyrin) Compounds Probed by Optical and EPR Spectroscopic  

E-print Network

by Optical and EPR Spectroscopic Methods Rene´e Shediac, Mike H. B. Gray, H. Tetsuo Uyeda, Robert C. Johnson), electroabsorption (Stark), and transient triplet-triplet absorption spectroscopic methods. Pump-probe fluorescence emitting states polarized exclusively along the axis defined by the ethyne moiety. Stark spectroscopic

240

A Cell Derived Active Contour (CDAC) Method for Robust Tracking in Low Frame Rate, Low Contrast Phase Microscopy - an Example: The Human hNT Astrocyte  

PubMed Central

The problem of automated segmenting and tracking of the outlines of cells in microscope images is the subject of active research. While great progress has been made on recognizing cells that are of high contrast and of predictable shape, many situations arise in practice where these properties do not exist and thus many interesting potential studies - such as the migration patterns of astrocytes to scratch wounds - have been relegated to being largely qualitative in nature. Here we analyse a select number of recent developments in this area, and offer an algorithm based on parametric active contours and formulated by taking into account cell movement dynamics. This Cell-Derived Active Contour (CDAC) method is compared with two state-of-the-art segmentation methods for phase-contrast microscopy. Specifically, we tackle a very difficult segmentation problem: human astrocytes that are very large, thin, and irregularly-shaped. We demonstrate quantitatively better results for CDAC as compared to similar segmentation methods, and we also demonstrate the reliable segmentation of qualitatively different data sets that were not possible using existing methods. We believe this new method will enable new and improved automatic cell migration and movement studies to be made. PMID:24358233

Nejati Javaremi, Alireza; Unsworth, Charles P.; Graham, E. Scott

2013-01-01

241

Validated spectrophotometric method for the determination, spectroscopic characterization and thermal structural analysis of duloxetine with 1,2-naphthoquinone-4-sulphonate  

NASA Astrophysics Data System (ADS)

A novel, selective, sensitive and simple spectrophotometric method was developed and validated for the determination of the antidepressant duloxetine hydrochloride in pharmaceutical preparation. The method was based on the reaction of duloxetine hydrochloride with 1,2-naphthoquinone-4-sulphonate (NQS) in alkaline media to yield orange colored product. The formation of this complex was also confirmed by UV-visible, FTIR, 1H NMR, Mass spectra techniques and thermal analysis. This method was validated for various parameters according to ICH guidelines. Beer's law is obeyed in a range of 5.0-60 ?g/mL at the maximum absorption wavelength of 480 nm. The detection limit is 0.99 ?g/mL and the recovery rate is in a range of 98.10-99.57%. The proposed methods was validated and applied to the determination of duloxetine hydrochloride in pharmaceutical preparation. The results were statistically analyzed and compared to those of a reference UV spectrophotometric method.

Ulu, Sevgi Tatar; Elmali, Fikriye Tuncel

2012-03-01

242

A spectroscopic analysis of macrospicules .  

NASA Astrophysics Data System (ADS)

We explore the nature of macrospicule structures, both off-limb and on-disk, and their possible relation to explosive events in the mid-solar atmosphere. We use high resolution spectroscopy obtained with the SoHO/SUMER instrument. We present a highly resolved spectroscopic analysis and line parameter study of time series data for such jets. We focus on two interesting off-limb events which rapidly propagate between the mid-transition region N IV 765 Å line formation (140 000 K) and the lower corona Ne VIII 770 Å line formation (630 000 K). In one example, a strong jet-like event is associated with a cool feature not present in the Ne VIII 770 Å line radiance or Doppler velocity maps. Our data reveals fast, repetitive plasma outflows with blue-shift velocities of ? 145 km s-1 in the lower solar atmosphere. The data suggests a strong role for smaller jets (spicules), as a precursor to macrospicule formation, which may have a common origin with explosive events.

Scullion, E.; Doyle, J. G.; Erdélyi, R.

243

A cross-site comparison of methods used for hydrogeologic characterization of the Galena-Platteville aquifer in Illinois and Wisconsin, with examples from selected Superfund sites  

USGS Publications Warehouse

The effectiveness of 28 methods used to characterize the fractured Galena-Platteville aquifer at eight sites in northern Illinois and Wisconsin is evaluated. Analysis of government databases, previous investigations, topographic maps, aerial photographs, and outcrops was essential to understanding the hydrogeology in the area to be investigated. The effectiveness of surface-geophysical methods depended on site geology. Lithologic logging provided essential information for site characterization. Cores were used for stratigraphy and geotechnical analysis. Natural-gamma logging helped identify the effect of lithology on the location of secondary- permeability features. Caliper logging identified large secondary-permeability features. Neutron logs identified trends in matrix porosity. Acoustic-televiewer logs identified numerous secondary-permeability features and their orientation. Borehole-camera logs also identified a number of secondary-permeability features. Borehole ground-penetrating radar identified lithologic and secondary-permeability features. However, the accuracy and completeness of this method is uncertain. Single-point-resistance, density, and normal resistivity logs were of limited use. Water-level and water-quality data identified flow directions and indicated the horizontal and vertical distribution of aquifer permeability and the depth of the permeable features. Temperature, spontaneous potential, and fluid-resistivity logging identified few secondary-permeability features at some sites and several features at others. Flowmeter logging was the most effective geophysical method for characterizing secondary-permeability features. Aquifer tests provided insight into the permeability distribution, identified hydraulically interconnected features, the presence of heterogeneity and anisotropy, and determined effective porosity. Aquifer heterogeneity prevented calculation of accurate hydraulic properties from some tests. Different methods, such as flowmeter logging and slug testing, occasionally produced different interpretations. Aquifer characterization improved with an increase in the number of data points, the period of data collection, and the number of methods used.

Kay, Robert T.; Mills, Patrick C.; Dunning, Charles P.; Yeskis, Douglas J.; Ursic, James R.; Vendl, Mark

2004-01-01

244

Methods and Tools to Align Curriculum to the Skills and Competencies Needed by the Workforce - an Example from Geospatial Science and Technology  

NASA Astrophysics Data System (ADS)

Geospatial science and technology (GST) including geographic information systems, remote sensing, global positioning systems and mobile applications, are valuable tools for geoscientists and students learning to become geoscientists. GST allows the user to analyze data spatially and temporarily and then visualize the data and outcomes in multiple formats (digital, web and paper). GST has evolved rapidly and it has been difficult to create effective curriculum as few guidelines existed to help educators. In 2010, the US Department of Labor (DoL), in collaboration with the National Geospatial Center of Excellence (GeoTech Center), a National Science Foundation supported grant, approved the Geospatial Technology Competency Mode (GTCM). The GTCM was developed and vetted with industry experts and provided the structure and example competencies needed across the industry. While the GTCM was helpful, a more detailed list of skills and competencies needed to be identified in order to build appropriate curriculum. The GeoTech Center carried out multiple DACUM events to identify the skills and competencies needed by entry-level workers. DACUM (Developing a Curriculum) is a job analysis process whereby expert workers are convened to describe what they do for a specific occupation. The outcomes from multiple DACUMs were combined into a MetaDACUM and reviewed by hundreds of GST professionals. This provided a list of more than 320 skills and competencies needed by the workforce. The GeoTech Center then held multiple workshops across the U.S. where more than 100 educators knowledgeable in teaching GST parsed the list into Model Courses and a Model Certificate Program. During this process, tools were developed that helped educators define which competency should be included in a specific course and the depth of instruction for that competency. This presentation will provide details about the process, methodology and tools used to create the Models and suggest how they can be used to create customized curriculum integrating geospatial science and technology into geoscience programs.

Johnson, A. B.

2012-12-01

245

Comparison of methods of estimating mean synoptic current structure in “stream coordinates” reference frames with an example from the Antarctic Circumpolar Current  

Microsoft Academic Search

Stream coordinates techniques, that is, methods of deriving the mean “synoptic” structures of narrow meandering ocean currents from Eulerian measurements, have been in use for nearly two decades and have resulted in improvements in our understanding of the dynamics and transports of such currents. A 2-year experiment in the Sub-Antarctic Front (SAF) southwest of Tasmania, involving overlapping arrays of inverted

Christopher S. Meinen; Douglas S. Luther

2003-01-01

246

Practical example for use of the supervised vicarious calibration (SVC) method on multisource hyperspectral imagery data - ValCalHyp airborne hyperspectral campaign under the EUFAR framework  

NASA Astrophysics Data System (ADS)

A novel approach for radiometric calibration and atmospheric correction of airborne hyperspectral (HRS) data, termed supervised vicarious calibration (SVC) was proposed by Brook and Ben-Dor in 2010. The present study was aimed at validating this SVC approach by simultaneously using several different airborne HSR sensors that acquired HSR data over several selected sites at the same time. The general goal of this study was to apply a cross-calibration approach to examine the capability and stability of the SVC method and to examine its validity. This paper reports the result of the multi sensors campaign took place over Salon de Provenance, France on behalf of the ValCalHyp project took place in 2011. The SVC method enabled the rectification of the radiometric drift of each sensor and improves their performance significantly. The flight direction of the SVC targets was found to be a critical issue for such correction and recommendations have been set for future utilization of this novel method. The results of the SVC method were examined by comparing ground-truth spectra of several selected validation targets with the image spectra as well as by comparing the classified water quality images generated from all sensors over selected water bodies.

Brook, A.; Ben Dor, E.

2014-09-01

247

Automated spectroscopic abundances of A and F-type stars using echelle spectrographs I. Reduction of ELODIE spectra and method of abundance determination  

E-print Network

This paper presents an automated method to determine detailed abundances for A and F-type stars. This method is applied on spectra taken with the ELODIE spectrograph. Since the standard reduction procedure of ELODIE is optimized to obtain accurate radial velocities but not abundances, we present a more appropriate reduction procedure based on IRAF. We describe an improvement of the method of Hill & Landstreet (1993) for obtaining Vsini, microturbulence and abundances by fitting a synthetic spectrum to the observed one. In particular, the method of minimization is presented and tested with Vega and the Sun. We show that it is possible, in the case of the Sun, to recover the abundances of 27 elements well within 0.1 dex of the commonly accepted values.

D. Erspamer; P. North

2001-12-14

248

Spectroscopic survey of LAMOST  

NASA Astrophysics Data System (ADS)

LAMOST is a special reflecting Schmidt telescope. LAMOST breaks through the bottleneck of the large scale spectroscopic survey observation with both large aperture (effective aperture of 3.6 - 4.9m) and wide field of view (5 degrees). It is an innovative active reflecting Schmidt configuration achieved by changing mirror surface continuously to achieve a series different reflecting Schmidt system in different moments. By using the parallel controllable fiber positioning technique, the focal surface of 1.75 meters in diameter accommodates 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST is the telescope of the highest spectrum acquiring rate. As a national large scientific project, LAMOST project was proposed formally in 1996. The construction was started in 2001 and completed in 2008. After commission period, LAMOST pilot survey was started in October 2011 and spectroscopic survey began in September 2012. From October 2011 to June 2013, LAMOST has obtained more than 2 million spectra of celestial objects. There are 1.7 million spectra of stars, in which the stellar parameters (effective temperature, surface gravity, metalicitiy and radial velocity) of more than 1 million stars was obtained. In the first period of spectroscopic survey of LAMOST, 5 million of stellar spectra will be obtained and will make substantial contribution to the study of the stellar astrophysics and the structure of the Galaxy, such as the spheroid substructure of the Galaxy, the galactic gravitational potential and the distribution of the dark matter in the Galaxy, the extremely metal poor stars and hypervelocity stars, the 3D extinction in the Galaxy, the structure of thin and thick disks of the Galaxy, and so on.

Zhao, Yongheng

2014-07-01

249

Two independent methods for mapping the grounding line of an outlet glacier - an example from the Astrolabe Glacier, Terre Adélie, Antarctica  

NASA Astrophysics Data System (ADS)

The grounding line is a key element of coastal outlet glaciers, acting on their dynamics. Accurately knowing its position is fundamental for both modelling the glacier dynamics and establishing a benchmark for later change detection. Here we map the grounding line of the Astrolabe Glacier in East Antarctica (66°41' S, 140°05' E), using both hydrostatic and tidal methods. The first method is based on new surface and ice thickness data from which the line of buoyant floatation is found. The second method uses kinematic GPS measurements of the tidal response of the ice surface. By detecting the transitions where the ice starts to move vertically in response to the tidal forcing we determine control points for the grounding line position along GPS profiles. Employing a two-dimensional elastic plate model, we compute the rigid short-term behaviour of the ice plate and estimate the correction required to compare the kinematic GPS control points with the previously determined line of floatation. These two approaches show consistency and lead us to propose a grounding line for the Astrolabe Glacier that significantly deviates from the lines obtained so far from satellite imagery.

Le Meur, E.; Sacchettini, M.; Garambois, S.; Berthier, E.; Drouet, A. S.; Durand, G.; Young, D.; Greenbaum, J. S.; Holt, J. W.; Blankenship, D. D.; Rignot, E.; Mouginot, J.; Gim, Y.; Kirchner, D.; de Fleurian, B.; Gagliardini, O.; Gillet-Chaulet, F.

2014-07-01

250

Determination of the asymptotic normalization coefficients for C14 + n ?C15, the C14(n,?)C15 reaction rate, and evaluation of a new method to determine spectroscopic factors  

NASA Astrophysics Data System (ADS)

The C14 + n ?C15 system has been used as a test case in the evaluation of a new method to determine spectroscopic factors that uses the asymptotic normalization coefficient (ANC). The method proved to be unsuccessful for this case. As part of this experimental program, the ANCs for the 15C ground state and first excited state were determined using a heavy-ion neutron transfer reaction as well as the inverse kinematics (d,p) reaction, measured at the Texas A&M Cyclotron Institute. The values C2s1/22=1.88±0.18 fm-1 for the ground state and C1d5/22=4.25±0.38×10-3 fm-1 for the first excited state (Eexc=740 keV) were obtained. The ANCs were used to evaluate the astrophysical direct neutron capture rate on C14, which was then compared with the most recent direct measurement and found to be in good agreement. A study of the C15 SF via its mirror nucleus F15 and a new insight into deuteron stripping theory are also presented.

McCleskey, M.; Mukhamedzhanov, A. M.; Trache, L.; Tribble, R. E.; Banu, A.; Eremenko, V.; Goldberg, V. Z.; Lui, Y.-W.; McCleskey, E.; Roeder, B. T.; Spiridon, A.; Carstoiu, F.; Burjan, V.; Hons, Z.; Thompson, I. J.

2014-04-01

251

Reflectance near-infrared spectroscopic method with a chemometric technique using partial least squares multivariate calibration for simultaneous determination of chondroitin, glucosamine, and ascorbic acid.  

PubMed

A reflectance near-infrared (RNIR) spectroscopy method was developed for simultaneous determination of chondroitin (CH), glucosamine (GO), and ascorbic acid (AS) in capsule powder. A simple preparation of the sample was done by grinding, sieving, and compression of the powder sample for improving RNIR spectra. Partial least squares (PLS-1 and PLS-2) was successfully applied to quantify the three components in the studied mixture using information included in RNIR spectra in the 4240-9780 cm(-1) range. The calibration model was developed with the three drug concentrations ranging from 50 to 150% of the labeled amount. The calibration models using pure standards were evaluated by internal validation, cross-validation, and external validation using synthetic and pharmaceutical preparations. The proposed method was applied for analysis of two pharmaceutical products. Both pharmaceutical products had the same active principle and similar excipients, but with different nominal concentration values. The results of the proposed method were compared with the results of a pharmacopoeial method for the same pharmaceutical products. No significant differences between the results were found. The standard error of prediction was 0.004 for CH, 0.003 for GO, and 0.005 for AS. The correlation coefficient was 0.9998 for CH, 0.9999 for GO, and 0.9997 for AS. The highly accurate and precise RNIR method can be used for QC of pharmaceutical products. PMID:22816263

El-Gindy, Alaa; Attia, Khalid Abdel-Salam; Nassar, Mohammad Wafaa; El-Abasawy, Nasr M A; Shoeib, Maisra Al-shabrawi

2012-01-01

252

Active Learning with Irrelevant Examples  

NASA Technical Reports Server (NTRS)

An improved active learning method has been devised for training data classifiers. One example of a data classifier is the algorithm used by the United States Postal Service since the 1960s to recognize scans of handwritten digits for processing zip codes. Active learning algorithms enable rapid training with minimal investment of time on the part of human experts to provide training examples consisting of correctly classified (labeled) input data. They function by identifying which examples would be most profitable for a human expert to label. The goal is to maximize classifier accuracy while minimizing the number of examples the expert must label. Although there are several well-established methods for active learning, they may not operate well when irrelevant examples are present in the data set. That is, they may select an item for labeling that the expert simply cannot assign to any of the valid classes. In the context of classifying handwritten digits, the irrelevant items may include stray marks, smudges, and mis-scans. Querying the expert about these items results in wasted time or erroneous labels, if the expert is forced to assign the item to one of the valid classes. In contrast, the new algorithm provides a specific mechanism for avoiding querying the irrelevant items. This algorithm has two components: an active learner (which could be a conventional active learning algorithm) and a relevance classifier. The combination of these components yields a method, denoted Relevance Bias, that enables the active learner to avoid querying irrelevant data so as to increase its learning rate and efficiency when irrelevant items are present. The algorithm collects irrelevant data in a set of rejected examples, then trains the relevance classifier to distinguish between labeled (relevant) training examples and the rejected ones. The active learner combines its ranking of the items with the probability that they are relevant to yield a final decision about which item to present to the expert for labeling. Experiments on several data sets have demonstrated that the Relevance Bias approach significantly decreases the number of irrelevant items queried and also accelerates learning speed.

Wagstaff, Kiri; Mazzoni, Dominic

2009-01-01

253

A numerical method for retrieving high oxygen isotope temperatures from plutonic igneous rocks: An example from the Laramie Anorthosite Complex, Wyoming, USA  

SciTech Connect

The Sybille Pit is a late-stage magnetite-ilmenite-plagioclase-bearing differentiate of the Laramie Anorthosite with a wide range of grain sizes and modal mineralogy. This variability makes Sybille an ideal locality in which to study the factors that affect isotopic thermometry in plutonic environments. The authors have developed a numerical model based on isotope exchange trajectories that retrieves close to magmatic temperatures for samples from Sybille. This method is based on the premise that hand sample-scale sub-systems close to exchange with each other at temperatures that exceed those of the constituent minerals. The temperature of hand-sample scale closure is retrieved by back calculating the isotope exchange trajectories to the temperature at which two samples with widely different model compositions are in isotopic equilibrium. Application of these methods to samples from Sybille provides promising results. Whereas conventional isotopic thermometry of individual samples yields a wide range of temperatures ([approximately]600 to > 1000 C) depending on the mineral-pair chosen, application of this numerical model to multiple samples yields temperatures of 1,070 [+-] 100 C which corresponds closely to the inferred solidus for these rocks.

Farquhar, J.; Chacko, T. (Univ. of Alberta, Edmonton (Canada). Dept. of Geology); Frost, B.R. (Univ. of Wyoming, Laramie, WY (United States))

1992-01-01

254

Complex-scaled equation-of-motion coupled-cluster method with single and double substitutions for autoionizing excited states: Theory, implementation, and examples  

NASA Astrophysics Data System (ADS)

Theory and implementation of complex-scaled variant of equation-of-motion coupled-cluster method for excitation energies with single and double substitutions (EOM-EE-CCSD) is presented. The complex-scaling formalism extends the EOM-EE-CCSD model to resonance states, i.e., excited states that are metastable with respect to electron ejection. The method is applied to Feshbach resonances in atomic systems (He, H-, and Be). The dependence of the results on one-electron basis set is quantified and analyzed. Energy decomposition and wave function analysis reveal that the origin of the dependence is in electron correlation, which is essential for the lifetime of Feshbach resonances. It is found that one-electron basis should be sufficiently flexible to describe radial and angular electron correlation in a balanced fashion and at different values of the scaling parameter, ?. Standard basis sets that are optimized for not-complex-scaled calculations (? = 0) are not sufficiently flexible to describe the ?-dependence of the wave functions even when heavily augmented by additional sets.

Bravaya, Ksenia B.; Zuev, Dmitry; Epifanovsky, Evgeny; Krylov, Anna I.

2013-03-01

255

Complex-scaled equation-of-motion coupled-cluster method with single and double substitutions for autoionizing excited states: Theory, implementation, and examples  

SciTech Connect

Theory and implementation of complex-scaled variant of equation-of-motion coupled-cluster method for excitation energies with single and double substitutions (EOM-EE-CCSD) is presented. The complex-scaling formalism extends the EOM-EE-CCSD model to resonance states, i.e., excited states that are metastable with respect to electron ejection. The method is applied to Feshbach resonances in atomic systems (He, H{sup -}, and Be). The dependence of the results on one-electron basis set is quantified and analyzed. Energy decomposition and wave function analysis reveal that the origin of the dependence is in electron correlation, which is essential for the lifetime of Feshbach resonances. It is found that one-electron basis should be sufficiently flexible to describe radial and angular electron correlation in a balanced fashion and at different values of the scaling parameter, {theta}. Standard basis sets that are optimized for not-complex-scaled calculations ({theta} = 0) are not sufficiently flexible to describe the {theta}-dependence of the wave functions even when heavily augmented by additional sets.

Bravaya, Ksenia B.; Zuev, Dmitry; Epifanovsky, Evgeny; Krylov, Anna I. [Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482 (United States)

2013-03-28

256

The limit of detection for explosives in spectroscopic differential reflectometry  

NASA Astrophysics Data System (ADS)

In the wake of recent terrorist attacks, such as the 2008 Mumbai hotel explosion or the December 25th 2009 "underwear bomber", our group has developed a technique (US patent #7368292) to apply differential reflection spectroscopy to detect traces of explosives. Briefly, light (200-500 nm) is shone on a surface such as a piece of luggage at an airport. Upon reflection, the light is collected with a spectrometer combined with a CCD camera. A computer processes the data and produces in turn a differential reflection spectrum involving two adjacent areas of the surface. This differential technique is highly sensitive and provides spectroscopic data of explosives. As an example, 2,4,6, trinitrotoluene (TNT) displays strong and distinct features in differential reflectograms near 420 nm. Similar, but distinctly different features are observed for other explosives. One of the most important criteria for explosive detection techniques is the limit of detection. This limit is defined as the amount of explosive material necessary to produce a signal to noise ratio of three. We present here, a method to evaluate the limit of detection of our technique. Finally, we present our sample preparation method and experimental set-up specifically developed to measure the limit of detection for our technology. This results in a limit ranging from 100 nano-grams to 50 micro-grams depending on the method and the set-up parameters used, such as the detector-sample distance.

Dubroca, Thierry; Vishwanathan, Karthik; Hummel, Rolf E.

2011-05-01

257

A Novel Spectroscopic Ellipsometer in the Infrared  

E-print Network

A Novel Spectroscopic Ellipsometer in the Infrared Proefschrift ter verkrijging van de graad van-Charles A novel spectroscopic ellipsometer in the infrared / by Jean-Charles Cigal. ­ Eindhoven : Technische . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.2 Spectroscopic ellipsometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1

Eindhoven, Technische Universiteit

258

High-Resolution Infrared-Vacuum Ultraviolet Photoion and Pulsed Field Ionization-Photoelectron Methods for Spectroscopic Studies of Neutrals and Cations  

Microsoft Academic Search

We show that by scanning the frequency of a single mode infrared (IR) optical parametric oscillator (IR-OPO) laser to excite the molecular species of interest and fixing the frequency of a vacuum ultraviolet (VUV) laser to photoionize the IR excited species, high-resolution IR spectra of polyatomic neutrals can be obtained with high sensitivity. The fact that this IR-VUV-photoion (IR-VUV-PI) method

Xi Xing; Beth Reed; Mi Kyung Bahng; Peng Wang; Hin Koo Woo; Sun Jong Baek; Chee Shing Lam; Cheuk Yiu Ng

2008-01-01

259

New validated liquid chromatographic and chemometrics-assisted UV spectroscopic methods for the determination of two multicomponent cough mixtures in syrup.  

PubMed

Multivariate spectrophotometric calibration and liquid chromatographic (LC) methods were applied to the determination of 2 multicomponent mixtures containing diprophylline, guaiphenesin, methylparaben, and propylparaben (Mixture 1), or clobutinol, orciprenaline, saccharin sodium, and sodium benzoate (Mixture 2). For the multivariate spectrophotometric calibration methods, principal component regression (PCR) and partial least-squares regression (PLS-1), a calibration set of the mixtures consisting of the components of each mixture was prepared in 0.1 M HCl. Analytical figures of merit such as sensitivity, selectivity, limit of quantitation, and limit of detection were determined for both PLS-1 and PCR. The LC separation was achieved on a reversed-phase C18 analytical column by using isocratic elution with 20 mM potassium dihydrogen phosphate, pH 3.3-acetonitrile (55 + 45, v/v) as the mobile phase and UV detection at 260 and 220 nm for Mixture 1 and Mixture 2, respectively. The proposed methods were validated and successfully applied to the analysis of pharmaceutical formulations and laboratory-prepared mixtures containing the 2 multicomponent combinations. PMID:18376584

Hadad, Ghada M; El-Gindy, Alaa; Mahmoud, Waleed M M

2008-01-01

260

Examples of sackungen in the French Western Alps and their geochronology based on the 10Be cosmic ray exposure dating method (Invited)  

NASA Astrophysics Data System (ADS)

In the French Alps, sackung scarps were often interpreted as surface traces of active faults. A detailed mapping of the Arc and Rognier mountains shows that these scarps result from deep-seated gravitational slope deformation (DSGSD). They are short (less than 2.1 km long), numerous and organized in swarms (5.3 km long at the Arc; 9 km long at Rognier). There are mainly uphill facing scarps developed on steep slopes. Open tension cracks are present at ridge tops. These sackung fractures created ridge-top troughs, closed depressions and multiple-crests landforms. That the sackung scarps are parallel to the contour lines, and that they result from opening of fractures or from normal slips, indicates that they are controlled by topography and gravity. In the Western Alps, glacial erosion and subsequent debuttressing of oversteepened slopes seem to be the main factors for the occurrence of sackungen. However, gradual loss of rock strength, groundwater fluctuations, subsidence due to evaporite dissolution and earthquake shaking, may contribute to their formation. For a better understanding of the origin of sackungen, chronological data are crucial. We used the cosmic ray exposure (CRE) dating method for deciphering the activity of the Arc and Rognier sackungen. This method allows quantification of the exposure duration of a surface to cosmic rays, by measuring the amount of accumulated cosmogenic nuclides in surficial rocks. Because sackung scarps usually form in hard rocks containing quartz, we used the 10Be cosmogenic nuclide which is produced in situ by spallation reactions on Si and O (36Cl can be used for limestone). The measurements were performed at ASTER, the French accelerator mass spectrometry facility located at the CEREGE laboratory in Aix-en-Provence. The CRE dating method allows direct dating of most of the geomorphologic structures involved in sackungen: sackung fault scarps, rock slopes, debris slopes, screes, rock glaciers, glacier-polished rock surface... In the Alps, the sackung faults are frequently found cutting relict rock glaciers. Our five samples of these periglacial landforms provide similar ages for the two studied areas (Arcs and Rognier) clustered between 11.5 and 9.4 ka BP. Sampling a single fault scarp at different heights allowed us to determine average slip rates (between 0.3 and 3.2 mm yr-1 at Rognier) and to estimate when the scarps initiated. The age of a scarp could also be accessed by sampling faulted debris slopes. Because sampling multiples scarps for CRE dating is relatively easy, we can access the geochronology of a whole sackung structure (22 CRE ages at Rognier). We found that the Arcs sackung and the Rognier sackung had contrasting behaviors and mechanisms. At the Arcs, DSGSD occurred through flexural toppling, with an upslope migration of the activity that stopped after a few thousand years (activity between 12 ka and 8 ka BP). At the Rognier Mountain, DSGSD occurred through deep conjugate faults. The fault slips are concomitant. Gravitational speading started before 12 ka and is probably still active at the same rate.

Hippolyte, J.; Bourles, D. L.; Braucher, R.; Léanni, L.; Chauvet, F.; Lebatard, A.; Arnold, M.; Aumaître, G.; Keddadouche, K.

2013-12-01

261

A new scheme for perturbative triples correction to (0,1) sector of Fock space multi-reference coupled cluster method: Theory, implementation, and examples  

NASA Astrophysics Data System (ADS)

We propose a new elegant strategy to implement third order triples correction in the light of many-body perturbation theory to the Fock space multi-reference coupled cluster method for the ionization problem. The computational scaling as well as the storage requirement is of key concerns in any many-body calculations. Our proposed approach scales as N6 does not require the storage of triples amplitudes and gives superior agreement over all the previous attempts made. This approach is capable of calculating multiple roots in a single calculation in contrast to the inclusion of perturbative triples in the equation of motion variant of the coupled cluster theory, where each root needs to be computed in a state-specific way and requires both the left and right state vectors together. The performance of the newly implemented scheme is tested by applying to methylene, boron nitride (B2N) anion, nitrogen, water, carbon monoxide, acetylene, formaldehyde, and thymine monomer, a DNA base.

Dutta, Achintya Kumar; Vaval, Nayana; Pal, Sourav

2015-01-01

262

A new scheme for perturbative triples correction to (0,1) sector of Fock space multi-reference coupled cluster method: Theory, implementation, and examples.  

PubMed

We propose a new elegant strategy to implement third order triples correction in the light of many-body perturbation theory to the Fock space multi-reference coupled cluster method for the ionization problem. The computational scaling as well as the storage requirement is of key concerns in any many-body calculations. Our proposed approach scales as N(6) does not require the storage of triples amplitudes and gives superior agreement over all the previous attempts made. This approach is capable of calculating multiple roots in a single calculation in contrast to the inclusion of perturbative triples in the equation of motion variant of the coupled cluster theory, where each root needs to be computed in a state-specific way and requires both the left and right state vectors together. The performance of the newly implemented scheme is tested by applying to methylene, boron nitride (B2N) anion, nitrogen, water, carbon monoxide, acetylene, formaldehyde, and thymine monomer, a DNA base. PMID:25637975

Dutta, Achintya Kumar; Vaval, Nayana; Pal, Sourav

2015-01-28

263

A practical method for estimating the orientation of eolian dune sands from deviated wells: An example from the Rotliegendes Group of the southern North Sea  

SciTech Connect

The identification of different sedimentary structures in eolian dune deposits (particularly those resulting from grain flow) allows estimation of the depositional dip angles of some bedding planes. By combining this dip-angle estimation with the overall dip of the formation (derived from seismic data and well correlation) and the wellbore orientation of a deviated well, two possible bedding-plane azimuths for the grain-flow deposits can usually be defined. By choosing wells deviated in a suitable direction and by assuming that major dune slip faces have a 180 [degree] range in possible dip azimuth centered around the regional formative wind direction, the cores can be oriented when the regional formative wind direction is known. Detailed data on bedding dip may thus be extracted from conventional unoriented cores in suitably deviated wells. This method can be used in conjunction with or in the absence of other core-orientation techniques and has been applied successfully in parts of the Rotliegendes Group of the southern North Sea. However, it may also be applied to any cored eolian dune deposits where a single regional wind direction has previously been determined and the well has a suitable deviation direction.

Carter, D.C. (Western Atlas International, Middlesex (United Kingdom)); Steele, R.P. (BP Exploration, Glasgow (United Kingdom))

1993-07-01

264

Spectroscopic and Photophysical Properties of the Trioxatriangulenium  

E-print Network

1 Spectroscopic and Photophysical Properties of the Trioxatriangulenium Carbocation and its and absorption spectroscopic techniques. A significant difference is observed of the photophysical parameters

265

Determination of structural and vibrational spectroscopic features of neutral and anion forms of dinicotinic acid by using NMR, infrared and Raman experimental methods combined with DFT and HF.  

PubMed

In this study; the experimental (NMR, infrared and Raman) and theoretical (HF and DFT) analysis of dinicotinic acid were presented. (1)H and (13)C NMR spectra were recorded in DMSO solution and chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method. The vibrational spectra of dinicotinic acid were recorded by FT-Raman and FT-IR spectra in the range of 4000-10 cm(-1) and 4000-400 cm(-1), respectively. To determine the most stable neutral conformer of molecule, the selected torsion angle was changed every 10° and molecular energy profile was calculated from 0° to 360°. The geometrical parameters and energies were obtained for all conformers form from density functional theory (DFT/B3LYP) and HF with 6-311++G(d,p) basis set calculations. However, the results of the most stable neutral and two anion forms (anion(-1) and anion(-2) forms) of dinicotinic acid are reported here. The complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational wavenumbers, calculated with scaled quantum mechanics (SQM) method and PQS program. PMID:23747433

Kose, E; Bardak, F; Atac, A; Karabacak, M; Cipiloglu, M A

2013-10-01

266

Vibrational spectroscopic studies, normal co-ordinate analysis, first order hyperpolarizability, HOMO-LUMO of midodrine by using density functional methods  

NASA Astrophysics Data System (ADS)

The FTIR (4000-400 cm-1), FT-Raman (4000-100 cm-1) and UV-Visible (400-200 nm) spectra of midodrine were recorded in the condensed state. The complete vibrational frequencies, optimized geometry, intensity of vibrational bands and atomic charges were obtained by using Density Functional Theory (DFT) with the help of 6-311++G(d,p) basis set. The first order hyperpolarizability (?) and related properties (?, ? and ??) of this molecular system were calculated by using DFT/6-311++G(d,p) method based on the finite-field approach. The assignments of the vibrational spectra have been carried out with the help of Normal Co-ordinate Analysis (NCA) following the scaled quantum mechanical force methodology. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using NBO analysis. From the recorded UV-Visible spectrum, the electronic properties such as excitation energies, oscillator strength and wavelength are calculated by DFT in water and gas methods using 6-311++G(d,p) basis set. The calculated HOMO and LUMO energies confirm that charge transfer occurs within the molecule. Besides MEP, NLO and thermodynamic properties were also calculated and interpreted. The electron density-based local reactivity descriptor such as Fukui functions was calculated to explain the chemical selectivity or reactivity site in midodrine.

Shahidha, R.; Al-Saadi, Abdulaziz A.; Muthu, S.

2015-01-01

267

Vibrational spectroscopic studies, normal co-ordinate analysis, first order hyperpolarizability, HOMO-LUMO of midodrine by using density functional methods.  

PubMed

The FTIR (4000-400 cm(-1)), FT-Raman (4000-100 cm(-1)) and UV-Visible (400-200 nm) spectra of midodrine were recorded in the condensed state. The complete vibrational frequencies, optimized geometry, intensity of vibrational bands and atomic charges were obtained by using Density Functional Theory (DFT) with the help of 6-311++G(d,p) basis set. The first order hyperpolarizability (?) and related properties (?, ? and ??) of this molecular system were calculated by using DFT/6-311++G(d,p) method based on the finite-field approach. The assignments of the vibrational spectra have been carried out with the help of Normal Co-ordinate Analysis (NCA) following the scaled quantum mechanical force methodology. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using NBO analysis. From the recorded UV-Visible spectrum, the electronic properties such as excitation energies, oscillator strength and wavelength are calculated by DFT in water and gas methods using 6-311++G(d,p) basis set. The calculated HOMO and LUMO energies confirm that charge transfer occurs within the molecule. Besides MEP, NLO and thermodynamic properties were also calculated and interpreted. The electron density-based local reactivity descriptor such as Fukui functions was calculated to explain the chemical selectivity or reactivity site in midodrine. PMID:25011041

Shahidha, R; Al-Saadi, Abdulaziz A; Muthu, S

2015-01-01

268

Standard test method for determination of impurities in plutonium: acid dissolution, ion exchange matrix separation, and inductively coupled plasma-atomic emission spectroscopic (ICP/AES) analysis  

E-print Network

1.1 This specification covers blended uranium trioxide (UO3), U3O8, or mixtures of the two, powders that are intended for conversion into a sinterable uranium dioxide (UO2) powder by means of a direct reduction process. The UO2 powder product of the reduction process must meet the requirements of Specification C 753 and be suitable for subsequent UO2 pellet fabrication by pressing and sintering methods. This specification applies to uranium oxides with a 235U enrichment less than 5 %. 1.2 This specification includes chemical, physical, and test method requirements for uranium oxide powders as they relate to the suitability of the powder for storage, transportation, and direct reduction to UO2 powder. This specification is applicable to uranium oxide powders for such use from any source. 1.3 The scope of this specification does not comprehensively cover all provisions for preventing criticality accidents, for health and safety, or for shipping. Observance of this specification does not relieve the user of th...

American Society for Testing and Materials. Philadelphia

2003-01-01

269

IZ Applet: Example 2  

NSDL National Science Digital Library

The unknown component in the IZApplet is a data source object. It can, therefore, pass its current and voltage values to any data listener. In this example, the current, voltage, and power absorbed by the unknown device are plotted on a data graph.

Christian, Wolfgang; Belloni, Mario

2008-02-09

270

IZ Applet: Example 3  

NSDL National Science Digital Library

The unknown circuit component in IZApplet is a data source. It can, therefore, pass its current and voltage values to a data listener. In this example, the current, voltage, and power absorbed by the unknown device are plotted on a data graph.

Christian, Wolfgang; Belloni, Mario

2008-02-09

271

Chapter 6. Solutions Example  

E-print Network

molar mass of the protein? #12;#12;· Example The Henry's low constant for oxygen dissolved in water is 4 conditions, calculate the concentration (in moles per liter) of dissolved oxygen in water10H8 (molar mass 128.17 g mol-1), is dissolved in 78.0 g of benzene (molar mass 78.0 g mol-1

Ihee, Hyotcherl

272

Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas  

SciTech Connect

Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given. Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

B.C. Stratton, M. Bitter, K.W. Hill, D.L. Hillis, and J.T. Hogan

2007-07-18

273

Spatially resolved energy dispersive x-ray spectroscopic method for in-situ evaluation of mechanical properties during the growth of a C - Pt composite nanowire  

SciTech Connect

A core-shell type C-Pt composite nanowire is fabricated using focused ion and electron beam induced chemical vapor deposition techniques. Using information from spatially resolved energy dispersive x-ray spectra, we detect the resonance vibration in the C-Pt composite nanowire. We use this method to measure the Young's moduli of the constituents (C, Pt) of the composite nanowire and also estimate the density of the FEB CVD grown Pt shell surrounding the C core. By measuring the resonance characteristics of the composite nanowire we estimate a Pt shell growth rate of ?0.9 nms{sup ?1}. The study is analyzed to suggest that the Pt shell growth mechanism is primarily governed by the sticking coefficient of the organometallic vapor on the C nanowire core.

Banerjee, Amit; Banerjee, S. S., E-mail: satyajit@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016 (India)

2014-05-15

274

Improvement of near infrared spectroscopic (NIRS) analysis of caffeine in roasted Arabica coffee by variable selection method of stability competitive adaptive reweighted sampling (SCARS)  

NASA Astrophysics Data System (ADS)

Coffee is the most heavily consumed beverage in the world after water, for which quality is a key consideration in commercial trade. Therefore, caffeine content which has a significant effect on the final quality of the coffee products requires to be determined fast and reliably by new analytical techniques. The main purpose of this work was to establish a powerful and practical analytical method based on near infrared spectroscopy (NIRS) and chemometrics for quantitative determination of caffeine content in roasted Arabica coffees. Ground coffee samples within a wide range of roasted levels were analyzed by NIR, meanwhile, in which the caffeine contents were quantitative determined by the most commonly used HPLC-UV method as the reference values. Then calibration models based on chemometric analyses of the NIR spectral data and reference concentrations of coffee samples were developed. Partial least squares (PLS) regression was used to construct the models. Furthermore, diverse spectra pretreatment and variable selection techniques were applied in order to obtain robust and reliable reduced-spectrum regression models. Comparing the respective quality of the different models constructed, the application of second derivative pretreatment and stability competitive adaptive reweighted sampling (SCARS) variable selection provided a notably improved regression model, with root mean square error of cross validation (RMSECV) of 0.375 mg/g and correlation coefficient (R) of 0.918 at PLS factor of 7. An independent test set was used to assess the model, with the root mean square error of prediction (RMSEP) of 0.378 mg/g, mean relative error of 1.976% and mean relative standard deviation (RSD) of 1.707%. Thus, the results provided by the high-quality calibration model revealed the feasibility of NIR spectroscopy for at-line application to predict the caffeine content of unknown roasted coffee samples, thanks to the short analysis time of a few seconds and non-destructive advantages of NIRS.

Zhang, Xuan; Li, Wei; Yin, Bin; Chen, Weizhong; Kelly, Declan P.; Wang, Xiaoxin; Zheng, Kaiyi; Du, Yiping

2013-10-01

275

Spectroscopic and electrical studies on Nd(3+), Zr(4+) ions doped nano-sized BaTiO3 ferroelectrics prepared by sol-gel method.  

PubMed

Lead free ferroelectric ceramics in the form of Ba(1-3x)Nd(2x)Ti(1-y)ZryO3 ((where x=0.025, y=0 (BT1), 0.025 (BT2), 0.05 (BT3)) were prepared using sol-gel method. The surface morphology and the orientation of grains of the present ceramics were examined using Field Emission Scanning Electron Microscope (FESEM) images. The effect of Nd(3+), Zr(4+) ions content on the BaTiO3 was studied using Raman and Fourier Transform Infrared (FTIR) spectroscopies. From the Raman analysis the band observed at ?838cm(-1) was attributed due to the presence of Nd(3+)-barium vacancy pairs. The FTIR studies suggested that the addition of Nd(3+) ions in A-site of BaTiO3 (ABO3) perovskite create lattice distortion by forming A-site vacancies and Zr(4+) ions in B-site of BaTiO3 induce the lattice distortion by forming ZrO6 octahedra in the place of TiO6 octahedra. Dielectric measurements of the samples were done at different frequencies from RT-150°C. Charge transportation phenomenon is explained using DC conductivity, which is found to increase with temperature. PMID:25448941

Sameera Devi, Ch; Kumar, G S; Prasad, G

2015-02-01

276

Combination of chiroptical, absorption and fluorescence spectroscopic methods reveals multiple, hydrophobicity-driven human serum albumin binding of the antimalarial atovaquone and related hydroxynaphthoquinone compounds.  

PubMed

High-affinity human serum albumin (HSA) binding of the C3-substituted antimalarial 2-hydroxy-1,4-naphthoquinone derivative atovaquone (ATQ) has been demonstrated and studied by circular dichroism (CD), UV/VIS absorption, fluorescence spectroscopy and affinity chromatography methods. The analysis of induced CD data generated upon HSA binding of ATQ revealed two high-affinity binding sites (K(a) ? 2 × 10(6) M(-1)). CD interaction studies and displacement of specific fluorescent and radioactive marker ligands indicated the contribution of both principal drug binding sites of HSA to complexation of ATQ, and also suggested the possibility of simultaneous binding of ATQ and some other drugs (e.g. warfarin, phenylbutazone, diazepam). Comparison of UV/VIS spectra of ATQ measured in aqueous solutions indicated the prevalence of the anionic species formed by dissociation of the 2-hydroxyl group. HSA binding of related natural hydroxynaphthoquinones, lapachol and lawsone also induces similar CD spectra. The much weaker binding affinity of lawsone (K(a) ? 10(4) M(-1)) bearing no C3 substituent highlights the importance of hydrophobic interactions in the strong HSA binding of ATQ and lapachol. Since neither drug exhibited significant binding to serum ?(1)-acid glycoprotein, HSA must be the principal plasma protein for the binding and transportation of 2-hydroxy-1,4-naphthoquinone-type compounds which are ionized at physiological pH values. PMID:20737064

Zsila, Ferenc; Fitos, Ilona

2010-11-01

277

Spectroscopic and electrical studies on Nd3+, Zr4+ ions doped nano-sized BaTiO3 ferroelectrics prepared by sol-gel method  

NASA Astrophysics Data System (ADS)

Lead free ferroelectric ceramics in the form of Ba(1-3x)Nd(2x)Ti(1-y)ZryO3 ((where x = 0.025, y = 0 (BT1), 0.025 (BT2), 0.05 (BT3)) were prepared using sol-gel method. The surface morphology and the orientation of grains of the present ceramics were examined using Field Emission Scanning Electron Microscope (FESEM) images. The effect of Nd3+, Zr4+ ions content on the BaTiO3 was studied using Raman and Fourier Transform Infrared (FTIR) spectroscopies. From the Raman analysis the band observed at ?838 cm-1 was attributed due to the presence of Nd3+-barium vacancy pairs. The FTIR studies suggested that the addition of Nd3+ ions in A-site of BaTiO3 (ABO3) perovskite create lattice distortion by forming A-site vacancies and Zr4+ ions in B-site of BaTiO3 induce the lattice distortion by forming ZrO6 octahedra in the place of TiO6 octahedra. Dielectric measurements of the samples were done at different frequencies from RT-150 °C. Charge transportation phenomenon is explained using DC conductivity, which is found to increase with temperature.

Sameera Devi, Ch.; Kumar, G. S.; Prasad, G.

2015-02-01

278

Vibrational spectroscopic (FTIR and FT Raman) studies, first order hyperpolarizabilities and HOMO, LUMO analysis of p-toluenesulfonyl isocyanate using ab initio HF and DFT methods.  

PubMed

The Fourier transform infrared (FTIR) and FT Raman spectra of p-toluenesulfonyl isocyanate (p-tosyl isocyanate) have been measured. The molecular geometry, vibrational frequencies, infrared intensities, Raman activities and atomic charges have been calculated by using ab initio HF and density functional theory calculation (B3LYP) with 6-311+G(d,p) basis set. Complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the observed FTIR and FT Raman data. The thermodynamic functions of the title compound were also performed with the aid of HF/6-311+G(d,p) and B3LYP/6-311+G(d,p) levels of theory. Simulated FTIR and FT Raman spectra for p-tosyl isocyanate showed good agreement with the observed spectra. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The dipole moment (?), polarizability (?) and the hyperpolarizability (?) values of the investigated molecule have been computed using HF and B3LYP methods. PMID:21795105

Parimala, K; Balachandran, V

2011-10-15

279

Elemental and structural analysis of silicon forms in herbal drugs using silicon-29 MAS NMR and WD-XRF spectroscopic methods.  

PubMed

The objective of this work was to study concentration of silicon and its structural forms present in herbal drugs. Equisetum arvense and Urtica dioica L. from teapot bags, dietary supplements (tablets and capsules) containing those herbs, dry extract obtained from a teapot bag of E. arvense, and samples of the latter herb harvested in wild habitat over four months were studied using wavelength dispersive X-ray spectroscopy (WD-XRF) and high-resolution solid-state (29)Si NMR. The highest concentration of Si, ca. 27mg/g, was found in the herbal material from the teapot bags containing E. arvense. The Si content in natural E. arvense (whole plants) increased from May to August by ca. 7mg/g, reaching value 26mg/g. Three different silicon forms were detected in the studied herbal samples: Si(OSi)4 (Q(4)), Si(OH)(OSi)3 (Q(3)) and Si(OH)2(OSi)2 (Q(2)). Those sites were populated in E. arvense in the following order: Q(4)?Q(3)>Q(2). A dramatic, ca. 50-fold decrease of the Si concentration during the infusion process was observed. The infusion process and the subsequent drying procedure augmented population of the Q(4) sites at the cost of the Q(2) sites. The WD-XRF and (29)Si NMR methods occurred useful and complementary in the study of herbal materials. PMID:21813258

Pajchel, L; Nykiel, P; Kolodziejski, W

2011-12-01

280

Infrared spectroscopic imaging of kidney tumor tissue  

NASA Astrophysics Data System (ADS)

Infrared spectroscopic imaging of cancerous kidney tissue was performed by means of FTIR microscopy. The spectra of thin tissue cryosections were collected with 64x64 MCT FPA detector and imaging area was increased up to 5.4×5.4 mm by mapping by means of PC controlled x,y stage. Chemical images of the samples were constructed using statistical treatment of the raw spectra. Several unsupervised and supervised statistical methods were used. The imaging results are compared with results of the standard histopathological analysis. It was concluded that application of method of cluster analysis ensures the best contrast of the images. It was found that border between cancerous and normal tissues visible in the infrared spectroscopic image corresponds with the border visible in histopathological image. Closer examination of the infrared spectroscopic image reveals that small domains of cancerous cells are found beyond the border in areas distant from the border up to 3 mm. Such domains are not visible in the histopathological images. The smallest domains found in the infrared images are approx. 60 ?m.

Sablinskas, V.; Steiner, G.; Koch, E.; Ceponkus, J.; Pucetaite, M.; Strazdaite, S.; Urboniene, V.; Jankevicius, F.

2011-02-01

281

Data Acquisition System for Instructional Spectroscopes  

NASA Astrophysics Data System (ADS)

This article aims to present the software for data acquisition developed in scientific initiation program - IC, for use in the design of a spectrometer built by students. The program was built in C++, a language in wide use today. The origin of spectra used is a simplified model of rustic spectroscope. This equipment basically consists of a box that does not allow light to enter, except through a slit made in the side of it, a diffraction media and a camera for data acquisition. After the image acquisition, one executes the data processing, followed by the usual steps of reduction and analysis of this type of tool. We have implemented a method for calibrating the spectroscope, through which one can compare the incidence of the photons with characteristic of each monochromatic wave. The final result is a one-dimensional spectrum that can be subsequently analyzed.

Almeida, C. B. S. B.; Hetem, A.

2014-10-01

282

Spectroscopic investigation of highly transient pinch plasmas  

SciTech Connect

The temporal evolution of neon pinch plasmas, generated in a 2 kJ plasma focus device, has been investigated by x-ray spectroscopic methods for two sets of device parameters. These two sets lead to characteristic differences of the K-shell emission. Stationary models are shown to fail to explain the experimental observations even qualitatively. Transient spectra analysis shows that the characteristic differences observed can be referred to different transient modes of plasma dynamics. The spectra analysis includes beside resonance lines also dielectronic satellites and recombination continua. The results concerning the development of the plasma parameters achieved by the spectra modeling are supported by independent measurements of the time resolved K-shell emission and by optical streak images of the pinch plasma dynamics, which confirms the reliability of the transient spectroscopic analysis presented. {copyright} {ital 1997} {ital The American Physical Society}

Bergmann, K.; Engel, A.; Lebert, R. [Lehrstuhl fuer Lasertechnik, Steinbachstrasse 15, D-52074 Aachen (Germany)] [Lehrstuhl fuer Lasertechnik, Steinbachstrasse 15, D-52074 Aachen (Germany); Rosmej, O.N. [MISDC VIIFTRI, 141570 Mendeleevo, Moscow (Russia)] [MISDC VIIFTRI, 141570 Mendeleevo, Moscow (Russia); Rosmej, F.B. [Institut fuer Experimentalphysik V, Ruhr-Universitaet Bochum,Universitaetsstrasse 150, D-44780 Bochum (Germany)] [Institut fuer Experimentalphysik V, Ruhr-Universitaet Bochum,Universitaetsstrasse 150, D-44780 Bochum (Germany); Gavrilescu, C. [University of Iasi, Copou 11, 6600-Iasi (Romania)] [University of Iasi, Copou 11, 6600-Iasi (Romania); Neff, W. [Fraunhofer Institut fuer Lasertechnik, Steinbachstrasse 15, D-52074 Aachen (Germany)] [Fraunhofer Institut fuer Lasertechnik, Steinbachstrasse 15, D-52074 Aachen (Germany)

1997-11-01

283

Experimental Mathematics: Examples, Methods and Implications  

E-print Network

in mathematics just the same as in physics. Kurt G¨odel2 1 Introduction Recent years have seen the flowering. Borel, Lecons sur la theorie des fonctions, 1928. 2 Kurt G¨odel, Collected Works, Vol. III, 1951. 1 #12

Borwein, Jonathan

284

Enhancing forensic science with spectroscopic imaging  

NASA Astrophysics Data System (ADS)

This presentation outlines the research we are developing in the area of Fourier Transform Infrared (FTIR) spectroscopic imaging with the focus on materials of forensic interest. FTIR spectroscopic imaging has recently emerged as a powerful tool for characterisation of heterogeneous materials. FTIR imaging relies on the ability of the military-developed infrared array detector to simultaneously measure spectra from thousands of different locations in a sample. Recently developed application of FTIR imaging using an ATR (Attenuated Total Reflection) mode has demonstrated the ability of this method to achieve spatial resolution beyond the diffraction limit of infrared light in air. Chemical visualisation with enhanced spatial resolution in micro-ATR mode broadens the range of materials studied with FTIR imaging with applications to pharmaceutical formulations or biological samples. Macro-ATR imaging has also been developed for chemical imaging analysis of large surface area samples and was applied to analyse the surface of human skin (e.g. finger), counterfeit tablets, textile materials (clothing), etc. This approach demonstrated the ability of this imaging method to detect trace materials attached to the surface of the skin. This may also prove as a valuable tool in detection of traces of explosives left or trapped on the surfaces of different materials. This FTIR imaging method is substantially superior to many of the other imaging methods due to inherent chemical specificity of infrared spectroscopy and fast acquisition times of this technique. Our preliminary data demonstrated that this methodology will provide the means to non-destructive detection method that could relate evidence to its source. This will be important in a wider crime prevention programme. In summary, intrinsic chemical specificity and enhanced visualising capability of FTIR spectroscopic imaging open a window of opportunities for counter-terrorism and crime-fighting, with applications ranging from analysis of trace evidence (e.g. in soil), tablets, drugs, fibres, tape explosives, biological samples to detection of gunshot residues and imaging of fingerprints.

Ricci, Camilla; Kazarian, Sergei G.

2006-09-01

285

The 1997 spectroscopic GEISA databank  

Microsoft Academic Search

The current version GEISA-97 of the computer-accessible database system GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques: Management and Study of Atmospheric Spectroscopic Information) is described. This catalogue contains 1,346,266 entries. These are spectroscopic parameters required to describe adequately the individual spectral lines belonging to 42 molecules (96 isotopic species) and located between 0 and 22,656cm-1. The featured molecules are

N. Jacquinet-Husson; E. Arie; J. Ballard; A. Barbe; G. Bjoraker; B. Bonnet; L. R. Brown; C. Camy-Peyret; J. P. Champion; A. Chedin; A. Chursin; C. Clerbaux; G. Duxbury; J.-M. Flaud; N. Fourrie; A. Fayt; G. Graner; R. Gamache; A. Goldman; Vl. Golovko; G. Guelachvili; J. M. Hartmann; J. C. Hilico; J. Hillman; G. Lefevre; E. Lellouch; O. V. Naumenko; V. Nemtchinov; D. A. Newnham; A. Nikitin; J. Orphal; A. Perrin; D. C. Reuter; C. P. Rinsland; L. Rosenmann; L. S. Rothman; N. A. Scott; J. Selby; L. N. Sinitsa; J. M. Sirota; A. M. Smith; K. M. Smith; Vl. G. Tyuterev; R. H. Tipping; S. Urban; P. Varanasi; M. Weber

1999-01-01

286

SDSS spectroscopic survey of stars  

SciTech Connect

In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is also producing a massive spectroscopic database. They discuss determination of stellar parameters, such as effective temperature, gravity and metallicity from SDSS spectra, describe correlations between kinematics and metallicity, and study their variation as a function of the position in the Galaxy. They show that stellar parameter estimates by Beers et al. show a good correlation with the position of a star in the g-r vs. u-g color-color diagram, thereby demonstrating their robustness as well as a potential for photometric parameter estimation methods. Using Beers et al. parameters, they find that the metallicity distribution of the Milky Way stars at a few kpc from the galactic plane is bimodal with a local minimum at [Z/Z{sub {circle_dot}}] {approx} -1.3. The median metallicity for the low-metallicity [Z/Z{sub {circle_dot}}] < =1.3 subsample is nearly independent of Galactic cylindrical coordinates R and z, while it decreases with z for the high-metallicity [Z/Z{sub {circle_dot}}] > -1.3 sample. they also find that the low-metallicity sample has {approx} 2.5 times larger velocity dispersion and that it does not rotate (at the {approx} 10 km/s level), while the rotational velocity of the high-metallicity sample decreases smoothly with the height above the galactic plane.

Ivezic, Zeljko; Schlegel, D.; Uomoto, A.; Bond, N.; Beers, T.; Allende Prieto, C.; Wilhelm, R.; Lee, Y.Sun; Sivarani, T.; Juric, M.; Lupton, R.; /Washington U., Seattle,

2007-01-01

287

FLAPS (Fatigue Life Analysis Programs): Computer Programs to Predict Cyclic Life Using the Total Strain Version of Strainrange Partitioning and Other Life Prediction Methods. Users' Manual and Example Problems, Version 1.0  

NASA Technical Reports Server (NTRS)

This manual presents computer programs FLAPS for characterizing and predicting fatigue and creep-fatigue resistance of metallic materials in the high-temperature, long-life regime for isothermal and nonisothermal fatigue. The programs use the Total Strain version of Strainrange Partitioning (TS-SRP), and several other life prediction methods described in this manual. The user should be thoroughly familiar with the TS-SRP and these life prediction methods before attempting to use any of these programs. Improper understanding can lead to incorrect use of the method and erroneous life predictions. An extensive database has also been developed in a parallel effort. The database is probably the largest source of high-temperature, creep-fatigue test data available in the public domain and can be used with other life-prediction methods as well. This users' manual, software, and database are all in the public domain and can be obtained by contacting the author. The Compact Disk (CD) accompanying this manual contains an executable file for the FLAPS program, two datasets required for the example problems in the manual, and the creep-fatigue data in a format compatible with these programs.

Arya, Vinod K.; Halford, Gary R. (Technical Monitor)

2003-01-01

288

Working Towards Accreditation by the International Standards Organization 15189 Standard: How to Validate an In-house Developed Method an Example of Lead Determination in Whole Blood by Electrothermal Atomic Absorption Spectrometry  

PubMed Central

Laboratories working towards accreditation by the International Standards Organization (ISO) 15189 standard are required to demonstrate the validity of their analytical methods. The different guidelines set by various accreditation organizations make it difficult to provide objective evidence that an in-house method is fit for the intended purpose. Besides, the required performance characteristics tests and acceptance criteria are not always detailed. The laboratory must choose the most suitable validation protocol and set the acceptance criteria. Therefore, we propose a validation protocol to evaluate the performance of an in-house method. As an example, we validated the process for the detection and quantification of lead in whole blood by electrothermal absorption spectrometry. The fundamental parameters tested were, selectivity, calibration model, precision, accuracy (and uncertainty of measurement), contamination, stability of the sample, reference interval, and analytical interference. We have developed a protocol that has been applied successfully to quantify lead in whole blood by electrothermal atomic absorption spectrometry (ETAAS). In particular, our method is selective, linear, accurate, and precise, making it suitable for use in routine diagnostics. PMID:25187889

Ramirez, Jose Manuel; Vest, Philippe; Chianea, Denis; Renard, Christophe

2014-01-01

289

2. Introduction and Three Elementary Examples 35. Three Intermediate Examples  

E-print Network

will cover some of the following: 1 2. Introduction and Three Elementary Examples 10. Archimedes and Pi 17 Examples 54. More Advanced Examples 68. Current Research and Conclusions 11. Archimedes and Pi 18. A 21st Advanced Examples 68. Current Research and Conclusions 11. Archimedes and Pi 18. A 21st Century postscript

Borwein, Jonathan

290

[Application of Raman spectroscopic technique to the identification and investigation of Chinese ancient jades and jade artifacts].  

PubMed

Laser Raman spectroscopic technique is one of the essential methods in scientific archaeological research, which belongs to the nondestructive analysis. As a very good nondestructive analysis approach, it has not been widely applied in the research of the Chinese ancient jade artifacts. First of all in the present paper the fundamentals of laser Raman spectroscopic technique and the new research progress in this field were reviewed. Secondly, the Raman spectra of five familiar jades including nephrite (mainly composed of tremolite), Xiuyan Jade (mainly composed of serpentine), Dushan Jade (mainly composed of anorthite and Zoisite), turquoise and lapis lazuli were summarized respectively. As for an example, the Raman spectra of the four Chinese ancient jade artifacts excavated from Liangzhu Site of Zhejiang Province and Yinxu Site of Anyang in Henan Province were compared with that of the nephrite sample in Hetian of Xinjiang Province. It was shown that the Raman spectroscopic technique is a good nondestructive approach to the identification and investigation of the structures and mineral composition of Chinese ancient jade artifacts. Finally, the limitations and the foreground of this technique were discussed. PMID:20101970

Zhao, Hong-Xia; Gan, Fu-Xi

2009-11-01

291

Reconstruction of Detached Divertor Plasma Conditions in DIII-D Using Spectroscopic and Probe Data  

SciTech Connect

For some divertor aspects, such as detached plasmas or the private flux zone, it is not clear that the controlling physics has been fully identified. This is a particular concern when the details of the plasma are likely to be important in modeling the problem--for example, modeling co-deposition in detached inner divertors. An empirical method of ''reconstructing'' the plasma based on direct experimental measurements may be useful in such situations. It is shown that a detached plasma in the outer divertor leg of DIII-D can be reconstructed reasonably well using spectroscopic and probe data as input to a simple onion-skin model and the Monte Carlo hydrogenic code, EIRENE. The calculated 2D distributions of n{sub e} and T{sub e} in the detached divertor were compared with direct measurements from the divertor Thomson scattering system, a diagnostic capability unique to DIII-D.

Stangeby, P; Fenstermacher, M

2004-12-03

292

2-Chloroethylisocyanate. Thermal decomposition and spectroscopic properties.  

PubMed

2-Chloroethylisocyanate has been studied in a thorough way. NMR, Raman, FTIR, and Ar-matrix vibrational spectra of the molecule are presented and discussed with the complement of ab initio and DFT methods. The spectroscopic results reveal the existence of anti and gauche conformers that are equally populated in the gas phase. Thermal decomposition between 393 and 648 K shows two different pathways depending on the temperature, which can be interpreted in terms of simple second- and first-order mechanisms, respectively. Quantum mechanical calculations reproduce the experimental results. PMID:21718037

Martínez Córdoba, Gustavo A; Ramos, Luis A; Ulic, Sonia E; Jios, Jorge L; DellaVédova, Carlos O; Pepino, Julieta; Burgos Paci, Maxi A; Argüello, Gustavo A; Ge, Maofa; Beckers, Helmut; Willner, Helge

2011-08-11

293

Spectroscopic Studies of Colloidal Solutions of Nanocrystalline Ru(bpy)3 2+-Zeolite Y  

E-print Network

Spectroscopic Studies of Colloidal Solutions of Nanocrystalline Ru(bpy)3 2+-Zeolite Y Norma B of Ru(bpy)3 2+-zeolite Y has made it possible to use conventional optical transmission spectroscopic methods to examine the entrapped Ru(bpy)3 2+ species within the zeolite. To prepare the suspensions

Dutta, Prabir K.

294

Spectroscopic investigation of protein corona  

NASA Astrophysics Data System (ADS)

Nanotechnology has revolutionalized the landscape of modern science and technology, including materials, electronics, therapeutics, bioimaging, sensing, and the environment. Research in the past decade has examined the fate of nanomaterials in vitro and in vivo, as well as the interactions between nanoparticles and biological and ecosystems using primarily toxicological and ecotoxicological approaches. However, due to the versatility in the physical and physicochemical properties of nanoparticles, and due to the vast complexity of their hosting systems, the solubility, transformation, and biocompatibility of nanomaterials are still poorly understood. Nanotechnology has been undergoing tremendous development in recent decades, driven by realized perceived applications of nanomaterials in electronics, therapeutics, imaging, sensing, environmental remediation, and consumer products. Nanoparticles on entering the blood stream undergo an identity change, they become coated with proteins. There are different kind of proteins present in blood. Proteins compete for getting coated over the surface of nanoparticle and this whole entity of proteins coated over nanoparticle surface is called Protein Corona. Proteins tightly bound to the surface of nanoparticle form hard corona and the ones loosely bound on the outer surface form soft corona. This dissertation is aimed at spectroscopic investigation of Protein Corona. Chapter I of this dissertation offers a comprehensive review of the literature based on nanomaterials with the focus on carbon based nanomaterilas and introduction to Protein Corona. Chapter II is based different methods used for Graphene Synthesis,different types of defects and doping. In Chapter III influence of defects on Graphene Protein Corona was investigated. Chapter IV is based on the study of Apoptosis induced cell death by Gold and silver nanoparticles. In vitro study of effect of Protein Corona on toxicity of cells was done.

Choudhary, Poonam

295

Fourier transform infared spectroscopic imaging for the identification of concealed drug residue particles and fingerprints  

NASA Astrophysics Data System (ADS)

Conventional FTIR spectroscopy and microscopy has been widely used in forensic science. New opportunities exist to obtain rapid chemical images and to enhance the sensitivity of detection of trace materials using attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy coupled with a focal-plane array (FPA) detector. In this work, the sensitivity of ATR-FTIR spectroscopic imaging using three different kinds of ATR crystals (Ge coupled with an infrared microscope, ZnSe and diamond) and resulting in three different optical arrangements for the detection of model drug particles is discussed. Model systems of ibuprofen and paracetamol particles having a size below 32 micrometers have been prepared by sieving. The sensitivity level in the three different approaches has been compared and it has been found that both micro and macro-ATR imaging methods have proven to be a promising techniques for the identification of concealed drug particles. To demonstrate the power and applicability of FTIR chemical imaging to forensic research, various examples are discussed. This includes investigation of the changes of chemical nature of latent fingerprint residue under controlled conditions of humidity and temperature studied by ATR-FTIR imaging. This study demonstrates the potential of spectroscopic imaging for visualizing the chemical changes of fingerprints.

Ricci, Camilla; Chan, K. L. Andrew; Kazarian, Sergei G.

2006-09-01

296

Halo nucleus Be-11: A spectroscopic study via neutron transfer  

E-print Network

The best examples of halo nuclei, exotic systems with a diffuse nuclear cloud surrounding a tightly-bound core, are found in the light, neutron-rich region, where the halo neutrons experience only weak binding and a weak, or no, potential barrier. Modern direct reaction measurement techniques provide powerful probes of the structure of exotic nuclei. Despite more than four decades of these studies on the benchmark one-neutron halo nucleus Be-11, the spectroscopic factors for the two bound states remain poorly constrained. In the present work, the Be-10(d,p) reaction has been used in inverse kinematics at four beam energies to study the structure of Be-11. The spectroscopic factors extracted using the adiabatic model, were found to be consistent across the four measurements, and were largely insensitive to the optical potential used. The extracted spectroscopic factor for a neutron in a nlj = 2s1/2 state coupled to the ground state of Be-10 is 0.71(5). For the first excited state at 0.32 MeV, a spectroscopic factor of 0.62(4) is found for the halo neutron in a 1p1/2 state.

K. T. Schmitt; K. L. Jones; A. Bey; S. H. Ahn; D. W. Bardayan; J. C. Blackmon; S. M. Brown; K. Y. Chae; K. A. Chipps; J. A. Cizewski; K. I. Hahn; J. J. Kolata; R. L. Kozub; J. F. Liang; C. Matei; M. Matoš; D. Matyas; B. Moazen; C. Nesaraja; F. M. Nunes; P. D. O'Malley; S. D. Pain; W. A. Peters; S. T. Pittman; A. Roberts; D. Shapira; J. F. Shriner Jr; M. S. Smith; I. Spassova; D. W. Stracener; A. N. Villano; G. L. Wilson

2012-03-19

297

Learning by Example.  

ERIC Educational Resources Information Center

A dialog shows how student-teacher interaction on problems can help students learn. Fifty sample problems are provided as starting points for class discussions from grade three through college. Six purposes such problems can serve are identified. A method of classroom presentation, the mathematical scavenger hunt, is discussed. (MP)

Butts, Thomas

1982-01-01

298

EJS Programming by Example  

NSDL National Science Digital Library

Chapter 2 of Open Source tools for Computational Physics: An introduction to EJS and Python. After brief instructions on setting up EJS, this chapter demonstrates how to do basic computer programming using EJS. All of the most basic, fundamental aspects of programming are covered: variables, mathematical operations, loops, if-statements, using and creating methods (a.k.a., subroutines), etc.

Engelhardt, Larry

2011-11-25

299

Spectroscopic investigation of the mechanism of photocatalysis.  

PubMed

Reaction mechanisms of various kinds of photocatalysts have been reviewed based on the recent reports, in which various spectroscopic techniques including luminol chemiluminescence photometry, fluorescence probe method, electron spin resonance (ESR), and nuclear magnetic resonance (NMR) spectroscopy were applied. The reaction mechanisms elucidated for bare and modified TiO2 were described individually. The modified visible light responsive TiO2 photocatalysts, i.e., Fe(III)-deposited metal-doped TiO2 and platinum complex-deposited TiO2, were studied by detecting paramagnetic species with ESR, •O2- (or H2O2) with chemiluminescence photometry, and OH radicals with a fluorescence probe method. For bare TiO2, the difference in the oxidation mechanism for the different crystalline form was investigated by the fluorescence probe method, while the adsorption and decomposition behaviors of several amino acids and peptides were investigated by 1H-NMR spectroscopy. PMID:25387352

Nosaka, Yoshio; Nishikawa, Masami; Nosaka, Atsuko Y

2014-01-01

300

The power of example  

NASA Astrophysics Data System (ADS)

The Secondary School "Teodor Balan" was evaluated by the National Agency for Quality Assurance with the highest score in an urban area of the county, and is part of the community Gura Humorului, a tourist resort of national interest since 2005. Starting with 2006 the local government implemented a Local Plan, which promotes the concept of sustainable development adopted at the Earth Summit in Rio de Janeiro, in 1992. Our school shares the concept of sustainable development and regularly re-evaluates the relationship between man and nature, advocates solidarity between generations, and has constantly developed various successful programs with the students, parents, teachers, and local companies and administration. Quarterly, we maintain and protect the river valley of Moldova arboretum nearby the reserve Oligocene "Stone Pine" and the natural reserve "Stone Hawk". Regarding the preservation of forests, teams of students and teachers from the school conduct activities of afforestation and greening, for the protection of birds. In order to raise public awareness about the harmful effects of radiation on the environment, my work degree in Physics, sustained in 2007, had as theme: Ionizing radiation and radiation protection. The effects of climate change and increasing temperature, as well as the extinction of species such as Amanita regalis and Tremiscus helvelloides mushrooms was studied by my biology colleague, Adriana. She obtained her Ist teaching degree in 2008, with the study "Diversity of macromycetes reported in natural ecosystems surrounding Gura Humorului". There were also organized 3 roundtables in a public awareness campaign initiated by the Ministry of Environment and Climate Change on "Integrated Nutrient Pollution Control", and the students learned to take test samples to determine water quality in wells and springs. In order to promote these activities performed by both teachers and students, we organized a National Symposium on "Life sciences at the beginning of the XXI century" with the participation of several schools in the country in 2009 and 2011. The papers presented were diverse and gave examples of various teaching experiences and scientific information. Topics by the teachers: The impact of tourism on the environment, Tornadoes, Natural science and environmental education in school, Air Pollution and health, Ecological education of children from primary school, The effects of electromagnetic radiation, Formation of an ecological mentality using chemistry, Why should we protect water, Environmental education, Education for the future, SOS Nature, Science in the twenty-first century, etc. Topics by students: Nature- the palace of thermal phenomena, Life depends on heat, Water Mysteries, Global Heating, The Mysterious universe, etc. In March 2013 our school hosted an interesting exchange of ideas on environmental issues between our students and those from Bulgaria, Poland and Turkey, during a symposium of the Comenius multilateral project "Conserving Nature". In order to present the results of protecting nature in their communities, two projects "Citizen" qualified in the Program Civitas in the autumn of 2013. "The Battle" continues both in nature and in classrooms, in order to preserve the environment.

Liliana Gheorghian, Mariana

2014-05-01

301

Infrared spectroscopic imaging for noninvasive detection of latent fingerprints.  

PubMed

The capability of Fourier transform infrared (FTIR) spectroscopic imaging to provide detailed images of unprocessed latent fingerprints while also preserving important trace evidence is demonstrated. Unprocessed fingerprints were developed on various porous and nonporous substrates. Data-processing methods used to extract the latent fingerprint ridge pattern from the background material included basic infrared spectroscopic band intensities, addition and subtraction of band intensity measurements, principal components analysis (PCA) and calculation of second derivative band intensities, as well as combinations of these various techniques. Additionally, trace evidence within the fingerprints was recovered and identified. PMID:17209909

Crane, Nicole J; Bartick, Edward G; Perlman, Rebecca Schwartz; Huffman, Scott

2007-01-01

302

Spectroscopic Factors in 16O and Nucleon Asymmetry  

E-print Network

The self-consistent Green's functions method is employed to study the spectroscopic factors of quasiparticle states around 16O, 28O, 40Ca and 60Ca. The Faddeev random phase approximation (FRPA) is used to account for the coupling of particles with collective excitation modes. Results for 16O are reviewed first. The same approach is applied to isotopes with large proton-neutron asymmetry to estimate its effect on spectroscopic factors. The results, based on the chiral N3LO force, exhibit an asymmetry dependence similar to that observed in heavy-ion knockout experiments but weaker in magnitude.

C. Barbieri; W. H. Dickhoff

2009-01-14

303

Build an Overhead Projector Spectroscope  

NSDL National Science Digital Library

This activity guide includes instructions for building a spectroscope using a standard classroom overhead projector. Learners can participate in the construction of the device or simply use it to explore light and the color spectrum. Learners can experiment with colored acetate film filters and bottles of colored solutions to see how they absorb and transmit light.

Katz, David A.

2002-01-01

304

NOUVEAU SPECTROSCOPE; PAR M. THOLLON.  

E-print Network

I4I NOUVEAU SPECTROSCOPE; PAR M. THOLLON. J'ai eu l'honneur de présenter récemment à l'Académie et qu'on fasse varier la position du couple sur le trajet d'un rayon d'une certaine réfrangibilité, il y

Boyer, Edmond

305

Continuous spectroscopic analysis of vanadous and vanadic ions  

Microsoft Academic Search

Spectroscopic methods were investigated for the determination of vanadium ions in aqueous solutions arising in the production of vanadium (11) formate and its use in the LOMI (Low Oxidation-state Metal Ion) process for the chemical decontamination of systems in nuclear power plants. In the LOMI process, a dilute solution of vanadous formate and picolinic acid is used. The vanadous formate

J. V. Bishop; R. A. Dutcher; M. S. Fisher; S. Kottle; R. A. Stowe

1993-01-01

306

Review of Spectroscopic Data for Measurements of Stratospheric Species  

NASA Technical Reports Server (NTRS)

Results and recommendations from a two day workshop are discussed. A review of the current status of experimental and theoretical spectroscopic data on molecules of stratospheric interest is given along with recommendations for additional research. Methods for disseminating new and existing data are also discussed.

Goldman, A. (editor); Hoell, J. M., Jr. (editor)

1980-01-01

307

Arsenate Adsorption On Ruthenium Oxides: A Spectroscopic And Kinetic Investigation  

EPA Science Inventory

Arsenate adsorption on amorphous (RuO2?1.1H2O) and crystalline (RuO2) ruthenium oxides was evaluated using spectroscopic and kinetic methods to elucidate the adsorption mechanism. Extended X-ray absorption fine structure spectroscopy (EXAFS) was ...

308

Spectroscopic study of solar twins and analogues  

NASA Astrophysics Data System (ADS)

Context. Many large stellar surveys have been and are still being carried out, providing huge amounts of data, for which stellar physical parameters will be derived. Solar twins and analogues provide a means to test the calibration of these stellar catalogues because the Sun is the best-studied star and provides precise fundamental parameters. Solar twins should be centred on the solar values. Aims: This spectroscopic study of solar analogues selected from the Geneva-Copenhagen Survey (GCS) at a resolution of 48 000 provides effective temperatures and metallicities for these stars. We test whether our spectroscopic parameters, as well as the previous photometric calibrations, are properly centred on the Sun. In addition, we search for more solar twins in our sample. Methods: The methods used in this work are based on literature methods for solar twin searches and on methods we developed in previous work to distinguish the metallicity-temperature degeneracies in the differential comparison of spectra of solar analogues versus a reference solar reflection spectrum. Results: We derive spectroscopic parameters for 148 solar analogues (about 70 are new entries to the literature) and verify with a-posteriori differential tests that our values are well-centred on the solar values. We use our dataset to assess the two alternative calibrations of the GCS parameters; our methods favour the latest revision. We show that the choice of spectral line list or the choice of asteroid or time of observation does not affect the results. We also identify seven solar twins in our sample, three of which are published here for the first time. Conclusions: Our methods provide an independent means to differentially test the calibration of stellar catalogues around the values of a well-known benchmark star, which makes our work interesting for calibration tests of upcoming Galactic surveys. Based on observations made with ESO Telescopes at the La Silla Observatory under programme ID 077.D-0525 and 090.D-0133.Table 1 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/574/A124Full Table 5 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/574/A124

Datson, Juliet; Flynn, Chris; Portinari, Laura

2015-02-01

309

An Overview of Methods for Monitoring Social Disparities in Cancer with an Example Using Trends in Lung Cancer Incidence by Area-Socioeconomic Position and Race-Ethnicity, 1992–2004  

PubMed Central

The authors provide an overview of methods for summarizing social disparities in health using the example of lung cancer. They apply four measures of relative disparity and three measures of absolute disparity to trends in US lung cancer incidence by area-socioeconomic position and race-ethnicity from 1992 to 2004. Among females, measures of absolute and relative disparity suggested that area-socioeconomic and race-ethnic disparities increased over these 12 years but differed widely with respect to the magnitude of the change. Among males, the authors found substantial disagreement among summary measures of relative disparity with respect to the magnitude and the direction of change in disparities. Among area-socioeconomic groups, the index of disparity increased by 47% and the relative concentration index decreased by 116%, while for race-ethnicity the index of disparity increased by 36% and the Theil index increased by 13%. The choice of a summary measure of disparity may affect the interpretation of changes in health disparities. Important issues to consider are the reference point from which differences are measured, whether to measure disparity on the absolute or relative scale, and whether to weight disparity measures by population size. A suite of indicators is needed to provide a clear picture of health disparity change. PMID:18344513

Harper, Sam; Lynch, John; Meersman, Stephen C.; Breen, Nancy; Davis, William W.; Reichman, Marsha E.

2008-01-01

310

Cerro Armazones spectroscopic survey of F dwarfs  

NASA Astrophysics Data System (ADS)

We present a spectroscopic survey of a sample of F stars that have not yet been searched for planets. The observations of 187 stars obtained with the Bochum Echelle Spectrographic Observer of the Cerro Armazones Observatory were aimed at nearby (closer than 70 pc) main-sequence stars without sufficient archive ([fiber-fed extended range optical spectrograph (FEROS)/high accuracy radial velocity planet search (HARPS)]) spectroscopy. The primary goal of the survey was to select the best candidates for radial-velocity searches of extrasolar planets. The spectra were analysed using the broadening-function technique, the method of choice for rapid rotators later than about A5. The analysis was focused not only at the determination of projected rotational velocity (defining precision of radial-velocity determination), but also at the detection of previously unknown spectroscopic binaries/multiples or stars showing strong line asymmetries. 12 previously unknown spectroscopic binaries/triples were detected. For all observed targets the spectral type was determined. About 140 stars are rotating faster than the resolution limit of 10 km s-1 sampling the onset of convection and slow rotation at mid-F spectral types in great detail. Radial-velocity precision of the data (about 100 m s-1) is insufficient to detect planets but could indicate most SB1 systems with stellar companions. As there are already 2-3 observations per object for these newly detected binary stars, only a few additional follow-up observations will be needed to obtain constraints on orbital parameters. We identified a sample of 68 bright F-type dwarf stars which are perfect targets for future planet searches. They rotate moderately or slowly and do not show any sign of binarity, pulsations, or surface activity.

Pribulla, Theodor; Sebastian, Daniel; Ammler-von Eiff, Matthias; Stahl, Otmar; Berndt, Alexandra; Chini, Rolf; Hoffmeister, Vera; Mugrauer, Markus; Neuhäuser, Ralph; Va?ko, Martin

2014-09-01

311

Calibrating Redshift Distributions Beyond Spectroscopic Limits with Cross-Correlations  

E-print Network

We describe a new method for measuring the true redshift distribution of any set of objects studied only photometrically. The angular cross-correlation between objects in a photometric sample with objects in some spectroscopic sample as a function of the spectroscopic z, in combination with standard correlation measurements, provides sufficient information to reconstruct the true redshift distribution of the photometric sample. This technique enables the robust calibration of photometric redshifts even beyond spectroscopic limits. The spectroscopic sample need not resemble the photometric one in galaxy properties, but must overlap in sky coverage and redshift range. We test this new technique with Monte Carlo simulations using realistic error estimates. RMS errors in recovering both the mean and sigma of the true, Gaussian redshift distribution of a single photometric redshift bin are 1.4x10^(-3) (sigma_z/0.1) (Sigma_p/10)^(-0.3) (dN_s/dz / 25,000)^(-0.5), where sigma_z is the true sigma of the redshift distribution, Sigma_p is the surface density of the photometric sample in galaxies/arcmin^2, and dN_s/dz is the number of galaxies with a spectroscopic redshift per unit z. We test the impact of redshift outliers and of a variety of sources of systematic error; none dominate measurement uncertainties in reasonable scenarios. With this method, the true redshift distributions of even arbitrarily faint photometric redshift samples may be determined to the precision required by proposed dark energy experiments (errors in mean and sigma below 3x10^(-3) at z~1) using expected extensions of current spectroscopic samples.

Jeffrey A. Newman

2008-05-12

312

Spectroscopic Techniques in the Chemistry Laboratory: A Science Enrichment Course for High School Teachers.  

ERIC Educational Resources Information Center

Describes a National Science Foundation sponsored enrichment program training high school teachers in modern innovative ideas. Specifically, the course described here was developed to present the uses and applications of spectroscopic methods. (CS)

Emert, Jack; Zeldin, Martel

1980-01-01

313

Spectroscopic phase microscopy for quantifying hemoglobin concentrations in intact red blood cells  

E-print Network

We report a practical method for label-free quantification of specific molecules using spectroscopic imaging of sample-induced phase shifts. Diffraction phase microscopy equipped with various wavelengths of light source ...

Park, YongKeun

314

Spectroscopic binaries with elliptical orbits  

E-print Network

The radial velocity curves of many spectroscopic binaries (SBs) are perturbed by gas streams or proximity effects. For SBs with circular orbits, these perturbations can give rise to spurious orbital eccentricities of high statistical significance. But tests to identify such anomalous orbits can be constructed since perturbed velocity curves are in general no longer Keplerian. The derived tests are applied both to synthetic and to observed velocity curves.

L. B. Lucy

2005-05-11

315

Size of spectroscopic calibration samples for cosmic shear photometric redshifts  

E-print Network

Weak gravitational lensing surveys using photometric redshifts can have their cosmological constraints severely degraded by errors in the photo-z scale. We explore the cosmological degradation vs the size of the spectroscopic survey required to calibrate the photo-z probability distribution. Previous work has assumed a simple Gaussian distribution of photo-z errors; here we describe a method for constraining an arbitrary parametric photo-z error model. As an example we allow the photo-z probability distribution to be the sum of $N_g$ Gaussians. To limit cosmological degradation to a fixed level, photo-z models with multiple Gaussians require up to 5 times larger calibration sample than one would estimate from assuming a single-Gaussian model. This degradation saturates at $N_g\\approx 4$. Assuming a single Gaussian when the photo-z distribution has multiple parameters underestimates cosmological parameter uncertainties by up to 35%. The size of required calibration sample also depends upon the shape of the fiducial distribution, even when the RMS photo-z error is held fixed. The required calibration sample size varies up to a factor of 40 among the fiducial models studied, but this is reduced to a factor of a few if the photo-z parameters are forced to be slowly varying with redshift. Finally we show that the size of the required calibration sample can be substantially reduced by optimizing its redshift distribution. We hope this study will help stimulate work on better understanding of photo-z errors.

Zhaoming Ma; Gary Bernstein

2008-09-07

316

Examples of Freshman Design Education  

Microsoft Academic Search

This paper looks at specific examples of how engineering programs around the United States are revising freshman year curricula to include engineering design. It builds on a companion paper [1] which provides a framework for viewing, interpreting and categorizing the various approaches to exposing freshman-level students to key design qualities. Example courses are grouped according to this framework, and similarities

SHERI SHEPPARD

1997-01-01

317

Analogical Reasoning with Typical Examples  

E-print Network

SEKIReport Analogical Reasoning with Typical Examples Manfred Kerber, Erica Melis, and Jorg Siekmann SEKI Report SR-92-13 #12;Analogical Reasoning with Typical Examples Manfred Kerber Erica Melis knowledge representation and reasoning. In real life situations more often than not, instead of a lengthy

Kerber, Manfred

318

Spectroscopic analysis of eclipsing SB2 stars: a case study  

NASA Astrophysics Data System (ADS)

The investigation of eclipsing spectroscopic binaries provides basic parameters of stars in a direct way. Whereas the measurable absolute masses can be used to calibrate stellar evolutionary scenarios, the effective temperatures derived from spectroscopic analysis are an important input to light curve and asteroseismic modelling. We compare different methods for investigating eclipsing SB2 stars focusing on radial velocity determination and spectrum decomposition and analysis. Used methods are the two-dimensional cross-correlation technique todcor, spectral disentangling with the Fourier transform-based korel program, and a grid search-based method of spectrum analysis using spectrum synthesis. The study is based on the investigation of two eclipsing SB2 stars observed by the Kepler satellite mission.

Lehmann, H.; Southworth, J.; Tkachenko, A.; Pavlovski, K.; Maceroni, C.; Ak, H.

2013-02-01

319

Determination of the asymptotic normalization coefficients for 14C + n <--> 15C, the 14C(n, gamma)15C reaction rate, and evaluation of a new method to determine spectroscopic factors  

SciTech Connect

The 14C + n <--> 15C system has been used as a test case in the evaluation of a new method to determine spectroscopic factors that uses the asymptotic normalization coefficient (ANC). The method proved to be unsuccessful for this case. As part of this experimental program, the ANCs for the 15C ground state and first excited state were determined using a heavy-ion neutron transfer reaction as well as the inverse kinematics (d,p) reaction, measured at the Texas A&M Cyclotron Institute. The ANCs were used to evaluate the astrophysical direct neutron capture rate on 14C, which was then compared with the most recent direct measurement and found to be in good agreement. A study of the 15C SF via its mirror nucleus 15F and a new insight into deuteron stripping theory are also presented.

McCleskey, M. [Texas A and M Univ., Cyclotron Inst., TX (United States); Mukhamedzhanov, A. M. [Texas A and M Univ., Cyclotron Inst., TX (United States); Trache, L. [Texas A and M Univ., Cyclotron Inst., TX (United States); Tribble, R. E. [Texas A and M Univ., Cyclotron Inst., TX (United States); Banu, A. [Texas A and M Univ., Cyclotron Inst., TX (United States); Eremenko, V. [Texas A and M Univ., Cyclotron Inst., TX (United States); Goldberg, V. Z. [Texas A and M Univ., Cyclotron Inst., TX (United States); Lui, Y. W. [Texas A and M Univ., Cyclotron Inst., TX (United States); McCleskey, E. [Texas A and M Univ., Cyclotron Inst., TX (United States); Roeder, B. T. [Texas A and M Univ., Cyclotron Inst., TX (United States); Spiridon, A. [Texas A and M Univ., Cyclotron Inst., TX (United States); Carstoiu, F. [National Inst. for Physics and Nuclear Engineering, Bucharest-Magurele (Romania); Burjan, V. [Nuclear Physics Inst., Czech Academy of Sciences, Prague (Czech Republic); Hons, Z. [Nuclear Physics Inst., Czech Academy of Sciences, Prague (Czech Republic); Thompson, I. J. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

2014-04-17

320

The far ultraviolet spectroscopic explorer  

NASA Technical Reports Server (NTRS)

The scientific objectives and performance characteristics of a new astronomy mission referred to as the far ultraviolet spectroscopic explorer, or FUSE are being defined by a team involving people experienced instrumental requirements that best meet the scientific needs. The team is intended to have a lifetime of about one year, ending with the submission of a report to NASA which could be used as the basis for an engineering design study. The principal objective of FUSE is to obtain astronomical spectra at wavelengths shorter than is possible with the Space Telescope.

Boggess, A.

1982-01-01

321

Spectroscopic classification of LSQ transients  

NASA Astrophysics Data System (ADS)

We report the optical spectroscopic classification of four supernovae candidates. The targets were supplied by the La Silla-Quest survey (see Hadjiyska et al., ATel #3812). All observations were performed on 25th Aug 2013 with the 4.2m William Herschel Telescope using ISIS, with R300B (3300 - 6000A, 3.4A resolution), R158R (5250 - 9746A, 7.2A resolution) and a dichroic at 5300A. Classifications were done with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024) and GELATO (Harutyunyan et al., 2008, A&A, 488, 383).

Wright, D.; Polshaw, J.; Fraser, M.; Smartt, S. J.; Kotak, R.; Smith, K.; Young, D.; Inserra, C.; Nicholl, M.; Baltay, C.; Ellman, N.; Hadjiyska, E.; McKinnon, R.; Rabinowitz, D.; Walker, E. S.; Feindt, U.; Kowalski, M.; Nugent, P.

2013-08-01

322

Research and Development of Non-Spectroscopic MEMS-Based Sensor Arrays for Targeted Gas Detection  

SciTech Connect

The ability to monitor the integrity of gas volumes is of interest to the stockpile surveillance community. Specifically, the leak detection of noble gases, at relevant concentration ranges and distinguished from other chemical species that may be simultaneously present, is particularly challenging. Aside from the laboratory-based method of gas chromatography-mass spectrometry (GC-MS), where samples may be collected by solid-phase microextraction (SPME) or cryofocusing, the other major approaches for gas-phase detection employ lasers typically operating in the mid-infrared wavelength region. While mass spectrometry can readily detect noble gases - the helium leak detector is an obvious example - laser-based methods such as infrared (IR) or Raman spectroscopy are completely insensitive to them as their monatomic nature precludes a non-zero dipole moment or changes in polarizability upon excitation. Therefore, noble gases can only be detected by one of two methods: (1) atomic emission spectroscopies which require the generation of plasmas through laser-induced breakdown, electrical arcing, or similar means; (2) non-spectroscopic methods which measure one or more physical properties (e.g., mass, thermal conductivity, density). In this report, we present our progress during Fiscal Year 2011 (FY11) in the research and development of a non-spectroscopic method for noble gas detection. During Fiscal Year 2010 (FY10), we demonstrated via proof-of-concept experiments that the combination of thermal conductivity detection (TCD) and coating-free damped resonance detection (CFDRD) using micro-electromechanical systems (MEMS) could provide selective sensing of these inert species. Since the MEMS-based TCD technology was directly adapted from a brassboard prototype commissioned by a previous chemical sensing project, FY11 efforts focused on advancing the state of the newer CFDRD method. This work, guided by observations previously reported in the open literature, has not only resulted in a substantially measureable increase in selectivity but has also revealed a potential method for mitigating or eliminating thermal drift that does not require a secondary reference sensor. The design of an apparatus to test this drift compensation scheme will be described. We will conclude this report with a discussion of planned efforts in Fiscal Year 2012 (FY12).

Loui, A; McCall, S K

2011-10-24

323

Mid-Infrared Spectroscopic Diagnostics of Galactic Nuclei  

E-print Network

In this paper I summarize the science motivations, as well as a few mid-infrared spectroscopic methods used to identify the principal mechanisms of energy production in dust enshrouded galactic nuclei. The development of the various techniques is briefly discussed. Emphasis is given to the use of the data which are becoming available with the infrared spectrograph (IRS) on Spitzer, as well as the results which have been obtained by IRS over the past two years.

Vassilis Charmandaris; the Spitzer/IRS Instrument Team

2006-07-13

324

Integrating Mass Scale Spectroscopic Processing  

NASA Astrophysics Data System (ADS)

This paper briefly presents the challenges in implementing the data driven pipelines which will support the delivery of science data products from three major new spectroscopic , namely the Gaia-ESO survey, the WEAVE multi-object spectrograph for the 4.2-m William Herschel Telescope, and the 4MOST multi-object spectrograph for the ESO VISTA telescope. We note the design solutions being implemented at the Cambridge Astronomical Survey Unit where an integrated approach in the delivery of a scalable data pipeline is being adopted. The design of the processing system is strongly science driven, which ensures that the analysis system delivers high quality data products to the science survey teams on the shortest possible time-scales, thereby allowing rapid scientific validation and exploitation of the data.

Walton, N. A.; Irwin, M. J.; Koposov, S.; Lewis, J. R.; Gonzales-Solarez, E.

2014-05-01

325

Logarithmic Scales: A Useful Example  

Microsoft Academic Search

Logarithmic intensity scales are widely encountered in astronomy (star magnitudes), acoustics (decibels), seismology (the Richter scale), and elsewhere. Yet students often have difficulty mastering the concept of logarithmic scales. With this note, I am calling attention to a case of the application of a logarithmic scale to something that is simple, transparent, and widely understood. The simplicity of the example

Albert A. Bartlett

2003-01-01

326

Calculation of multicomponent chemical equilibria in gas-solid- liquid systems: calculation methods, thermochemical data, and applications to studies of high-temperature volcanic gases with examples from Mount St. Helens  

USGS Publications Warehouse

This paper documents the numerical formulations, thermochemical data base, and possible applications of computer programs, SOLVGAS and GASWORKS, for calculating multicomponent chemical equilibria in gas-solid-liquid systems. SOLVGAS and GASWORKS compute simultaneous equilibria by solving simultaneously a set of mass balance and mass action equations written for all gas species and for all gas-solid or gas-liquid equilibria. Examples of gas-evaporation-from-magma and precipitation-with-cooling calculations for volcanic gases collected from Mount St. Helens are shown. -from Authors

Symonds, R.B.; Reed, M.H.

1993-01-01

327

Determination of depleted uranium in environmental samples by gamma-spectroscopic techniques  

Microsoft Academic Search

The military use of depleted uranium initiated the need for an efficient and reliable method to detect and quantify DU contamination in environmental samples. This paper presents such a method, based on the gamma spectroscopic determination of 238U and 235U. The main advantage of this method is that it allows for a direct determination of the U isotope ratio, while

D. J Karangelos; M. J Anagnostakis; E. P Hinis; S. E Simopoulos; Z. S Zunic

2004-01-01

328

Surface spectroscopic characterization of titanium implant materials  

NASA Astrophysics Data System (ADS)

Titanium is one of the most commonly used biomaterials for dental and orthopedic applications. Its excellent tissue compatibility is mainly due to the properties of the stable oxide layer which is present on the surface. This paper reports a detailed spectroscopic characterization of the surface composition of non-alloyed Ti implant materials, prepared according to procedures commonly used in clinical practice (machining, ultrasonic cleaning and sterilization). The main methods of characterization are XPS and AES, and complementary information is obtained by SIMS, EDX and NMA (nuclear microanalysis). The surface of the implants is found to consist of a thin surface oxide which is covered by a carbon-dominated contamination layer. By comparison with reference spectra from single crystal TiO 2 (rutile) the composition of the surface oxide is shown to be mainly TiO 2, with minor amounts of suboxides and TiN x. The thickness of the surface oxides is 2-6 nm, depending on the method of sterilization. The surface contamination layer is found to vary considerably from sample to sample and consists of mainly hydrocarbons with trace amounts of Ca, N, S, P, Cl. Some differences in surface composition between directly prepared surfaces, and some possible contamination sources, are identified and discussed shortly.

Lausmaa, Jukka; Kasemo, Bengt; Mattsson, Håkan

1990-04-01

329

AN H-BAND SPECTROSCOPIC METALLICITY CALIBRATION FOR M DWARFS  

SciTech Connect

We present an empirical near-infrared (NIR) spectroscopic method for estimating M dwarf metallicities, based on features in the H band, as well as an implementation of a similar published method in the K band. We obtained R {approx} 2000 NIR spectra of a sample of M dwarfs using the NASA IRTF-SpeX spectrograph, including 22 M dwarf metallicity calibration targets that have FGK companions with known metallicities. The H-band and K-band calibrations provide equivalent fits to the metallicities of these binaries, with an accuracy of {+-}0.12 dex. We derive the first empirically calibrated spectroscopic metallicity estimate for the giant planet-hosting M dwarf GJ 317, confirming its supersolar metallicity. Combining this result with observations of eight other M dwarf planet hosts, we find that M dwarfs with giant planets are preferentially metal-rich compared to those that host less massive planets. Our H-band calibration relies on strongly metallicity-dependent features in the H band, which will be useful in compositional studies using mid- to high-resolution NIR M dwarf spectra, such as those produced by multiplexed surveys like SDSS-III APOGEE. These results will also be immediately useful for ongoing spectroscopic surveys of M dwarfs.

Terrien, Ryan C.; Mahadevan, Suvrath; Bender, Chad F.; Deshpande, Rohit; Ramsey, Lawrence W.; Bochanski, John J., E-mail: rct151@psu.edu [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)

2012-03-10

330

Photometric and Spectroscopic Analysis of the Eclipsing Binary DQ Velorum  

NASA Astrophysics Data System (ADS)

In order to obtain the main stellar and orbital parameters of the Double Periodic Variable DQ Velorum, we have carried out a series of spectroscopic and photometric observations covering several orbital cycles. We disentangle DQ Vel composite spectra and measure radial velocities using an iterative method for double spectroscopic binaries. We obtain the spectroscopic mass ratio q=0.31±0.03 from the radial velocity curves. We compare our single-lined spectra with a grid of synthetic spectra and estimate the temperature of the stars. We also model the V-band light curve using a fitting method based on the simplex algorithm including an accretion disc. We find that DQ Vel is a semi-detached system consisting on a B3V gainer (T_{g}=18500±500 K) and an A1III donor star (T_{d}=9400±100 K) plus an extended accretion disc around the gainer. We compare the stellar and disc parameters of DQ Vel with the DPV V393 Sco to investigate the nature and evolution of these two similar DPV systems.

Barría, D.; Mennickent, R. E.; Schmidtobreick, L.; Djuraševi?, G.; Ko?aczkowski, Z.; Michalska, G.; Vu?kovi?, M.; Niemczura, E.

331

Spectroscopic Constants and Potential Energy Curves of PbI  

NASA Astrophysics Data System (ADS)

The spectroscopic constants and potential energy curves of the PbI diatomic were computed using complete active space SCF (CASSCF) followed by first-order CI (FOCI) and second-order CI (SOCI) calculations which included 607 000 configurations. Spin-orbit coupling was studied using the relativistic CI (RCI) method. The spectroscopic properties of the 2? 1/2 state are Re = 2.885 Å, ? e, = 153 cm -1, and De = 2.54(eV), while for the 2? 3/2 state the corresponding values are Re = 2.859 Å, ? e = 162 cm -1, and Te = 8255 cm -1. Our computed constants are in good agreement with experiment for the observed states. We also computed the properties and curves for several excited states which are yet to be observed.

Benavidesgarcia, M.; Balasubramanian, K.

1993-10-01

332

Origin of evolutionary novelty: examples from limbs.  

PubMed

Classic hypotheses of vertebrate morphology are being informed by new data and new methods. Long nascent issues, such as the origin of tetrapod limbs, are being explored by paleontologists, molecular biologists, and functional anatomists. Progress in this arena will ultimately come down to knowing how macroevolutionary differences between taxa emerge from the genetic and phenotypic variation that arises within populations. The assembly of limbs over developmental and evolutionary time offers examples of the major processes at work in the origin of novelties. Recent comparative developmental analyses demonstrate that many of the mechanisms used to pattern limbs are ancient. One of the major consequences of this phenomenon is parallelism in the evolution of anatomical structures. Studies of both the fossil record and intrapopulational variation of extant populations reveal regularities in the origin of variation. These examples reveal processes acting at the level of populations that directly affect the patterns of diversity observed at higher taxonomic levels. PMID:11921033

Shubin, Neil H

2002-04-01

333

Spectroscopic Families Among Diffuse Interstellar Bands  

E-print Network

Looking for spectroscopic families in the whole set of discovered diffuse interstellar bands (DIBs) is an indirect trial of solving the problem of DIBs' carriers. Basing on optical high resolution spectra, covering the range from 5655 to 7020 \\AA, we found few relatively strong DIBs which are not well correlated one with another and therefore they may play a role of representatives of separate spectroscopic families. In the next step we indicated DIBs which tend to follow the behaviour of their representatives. As a result of our analysis we propose few, probably not complete yet, spectroscopic families of DIBs.

K. Bryndal; B. Wszolek

2007-12-10

334

Scanning tunneling microscopy detection of spin polarized resonant surface bands: The example of Fe(001)  

Microsoft Academic Search

We study theoretically the effect of a spin polarized resonant surface band on the conductance of scanning tunneling spectroscope with a spin polarized tip (SP-STM). Using the example of the Fe(001) surface, we show that a minority-spin surface state can induce a bias dependence of the tunneling differential conductance which depends strongly on the orientation of the magnetization in the

Athanasios N. Chantis; Darryl L. Smith; J. Fransson; A. V. Balatsky

2009-01-01

335

Towards Extraction of Massive DIB Datasets from Stellar Spectroscopic Surveys  

NASA Astrophysics Data System (ADS)

Medium to high-resolution stellar spectroscopic surveys can potentially be used to build DIB databases by means of automated methods of analysis. Multiplex spectrographs increase strongly those potentialities and allow small-scale variability studies. Because measurements of the stellar parameters are generally the primary goal of the surveys, synthetic spectra can be computed and used to extract DIBs from late-type star data. Large datasets should allow deeper investigations on the DIB variability in response to stellar radiation fields, DIB reddening relationships, and help localizing interstellar clouds. Here we describe our attempts to build and test automated methods adapted to both early and late type stars.

Lallement, R.; Chen, H. C.; Puspitarini, L.; Bonifacio, P.; Babusiaux, C.; Hill, V.

2014-02-01

336

MR Spectroscopy and Spectroscopic Imaging of the Brain  

PubMed Central

Magnetic resonance spectroscopy (MRS) and the related technique of magnetic resonance spectroscopic imaging (MRSI) are widely used in both clinical and preclinical research for the non-invasive evaluation of brain metabolism. They are also used in medical practice, although their ultimate clinical value continues to be a source of discussion. This chapter reviews the general information content of brain spectra and commonly used protocols for both MRS and MRSI and also touches on data analysis methods and quantitation. The main focus is on proton MRS for application in humans, but many of the methods are also applicable to other nuclei and studies of animal models as well. PMID:21279603

Zhu, He; Barker, Peter B.

2012-01-01

337

Radial velocity-acceleration curve analysis of the spectroscopic binary stars by the nonlinear regression  

E-print Network

We will introduce a new method to derive the orbital elements of the spectroscopic binary stars. Fitting the adopted radial velocity curves on the measured experimental data, the corresponding radial acceleration data are obtained. The orbital parameters are estimated by the nonlinear least squares of the radial velocity-acceleration curves. This method is implemented for the three double line spectroscopic binary systems RZ CAS, CC Cas and V1130 Tau. Numerical calculations show that the result are in good agreement with the those obtained by others using the method of Lehmann-Filh\\'{e}s.

K. Karami; H. Teimoorinia

2011-01-31

338

Infrared spectroscopic imaging for histopathologic recognition.  

PubMed

The process of histopathology, comprising tissue staining and morphological pattern recognition, has remained largely unchanged for over 140 years. Although it is integral to clinical and research activities, histopathologic recognition remains a time-consuming, subjective process to which only limited statistical confidence can be assigned because of inherent operator variability. Although immunohistochemical approaches allow limited molecular detection, significant challenges remain in using them for quantitative, automated pathology. Vibrational spectroscopic approaches, by contrast, directly provide nonperturbing molecular descriptors, but a practical spectroscopic protocol for histopathology is lacking. Here we couple high-throughput Fourier transform infrared (FTIR) spectroscopic imaging of tissue microarrays with statistical pattern recognition of spectra indicative of endogenous molecular composition and demonstrate histopathologic characterization of prostatic tissue. This automated histologic segmentation is applied to routine archival tissue samples, incorporates well-defined tests of statistical significance and eliminates any requirement for dyes or molecular probes. Finally, we differentiate benign from malignant prostatic epithelium by spectroscopic analyses. PMID:15793574

Fernandez, Daniel C; Bhargava, Rohit; Hewitt, Stephen M; Levin, Ira W

2005-04-01

339

Interaction of salmon gonadotropin subunits : spectroscopic studies  

E-print Network

Interaction of salmon gonadotropin subunits : spectroscopic studies R. SALESSE, J. GARNIER, B en Josas, France Summary. Pituitary gonadotropins of female and male pacific salmon Oncorhynchus) and in salmon (Donaldson et al., 1972), although physicochemical, biological or immunological evidence for two

Paris-Sud XI, Université de

340

CSP spectroscopic classification of two supernovae  

NASA Astrophysics Data System (ADS)

On behalf of the Carnegie Supernova Project, we report spectroscopic classification of PSN J08293820-1717473 and ASASSN-14my (ATel#6860), based on visual-wavelength spectra obtained with the Nordic Optical Telescope (+Alfosc).

Stritzinger, M.; Hsiao, E.; Taddia, F.; Morrell, N.

2015-01-01

341

Spectroscopic Classification of ASAS-SN Supernovae  

NASA Astrophysics Data System (ADS)

We report optical spectroscopic observations of ASAS-SN transients (ATel #6809, #6830, #6836, #6858, #6860, #6864, #6867) obtained on UT 2015 January 2-4 with IMACS (range 3600-9600 Angstroms, FWHM res.

Shappee, B. J.; Prieto, J. L.; Holoien, T. W.-S.; Stanek, K. Z.; Kochanek, C. S.; Davis, A. B.; Simonian, G.; Basu, U.; Goss, N.; Beacom, J. F.; Bersier, D.; Dong, Subo; Wozniak, P. R.; Brimacombe, J.; Szczygiel, D.; Pojmanski, G.

2015-01-01

342

Improved spectroscopic parameters for transiting planet hosts  

E-print Network

We report homogeneous spectroscopic determinations of the effective temperature, metallicity, and projected rotational velocity for the host stars of 56 transiting planets. Our analysis is based primarily on the stellar ...

Winn, Joshua Nathan

343

Spectroscopic study of the acetylene species  

E-print Network

This thesis describes recent spectroscopic studies of acetylene and its HCCD isotopomer. Three different kinds of experiments have been performed: Laser-Induced Fluorescence (LIF), Dispersed Fluorescence (DF), and Stimulated ...

Duan, Zicheng, 1976-

2003-01-01

344

17 CFR 248.102 - Examples.  

Code of Federal Regulations, 2010 CFR

...SECURITIES AND EXCHANGE COMMISSION (CONTINUED) REGULATIONS S-P AND S-AM Regulation S-AM: Limitations on Affiliate Marketing § 248.102 Examples. The examples in this subpart are not exclusive. The examples in this subpart...

2010-04-01

345

17 CFR 248.102 - Examples.  

Code of Federal Regulations, 2014 CFR

...EXCHANGE COMMISSION (CONTINUED) REGULATIONS S-P, S-AM, AND S-ID Regulation S-AM: Limitations on Affiliate Marketing § 248.102 Examples. The examples in this subpart are not exclusive. The examples in this subpart...

2014-04-01

346

16 CFR 680.2 - Examples.  

Code of Federal Regulations, 2013 CFR

... 680.2 Section 680.2 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT AFFILIATE MARKETING § 680.2 Examples. The examples in this part are not exclusive. Compliance with an example, to the...

2013-01-01

347

17 CFR 248.102 - Examples.  

Code of Federal Regulations, 2013 CFR

...SECURITIES AND EXCHANGE COMMISSION (CONTINUED) REGULATIONS S-P AND S-AM Regulation S-AM: Limitations on Affiliate Marketing § 248.102 Examples. The examples in this subpart are not exclusive. The examples in this subpart...

2013-04-01

348

16 CFR 680.2 - Examples.  

Code of Federal Regulations, 2012 CFR

... 680.2 Section 680.2 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT AFFILIATE MARKETING § 680.2 Examples. The examples in this part are not exclusive. Compliance with an example, to the...

2012-01-01

349

17 CFR 248.102 - Examples.  

Code of Federal Regulations, 2011 CFR

...SECURITIES AND EXCHANGE COMMISSION (CONTINUED) REGULATIONS S-P AND S-AM Regulation S-AM: Limitations on Affiliate Marketing § 248.102 Examples. The examples in this subpart are not exclusive. The examples in this subpart...

2011-04-01

350

17 CFR 248.102 - Examples.  

Code of Federal Regulations, 2012 CFR

...SECURITIES AND EXCHANGE COMMISSION (CONTINUED) REGULATIONS S-P AND S-AM Regulation S-AM: Limitations on Affiliate Marketing § 248.102 Examples. The examples in this subpart are not exclusive. The examples in this subpart...

2012-04-01

351

16 CFR 680.2 - Examples.  

Code of Federal Regulations, 2014 CFR

... 680.2 Section 680.2 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT AFFILIATE MARKETING § 680.2 Examples. The examples in this part are not exclusive. Compliance with an example, to the...

2014-01-01

352

16 CFR 680.2 - Examples.  

Code of Federal Regulations, 2010 CFR

... 680.2 Section 680.2 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT AFFILIATE MARKETING § 680.2 Examples. The examples in this part are not exclusive. Compliance with an example, to the...

2010-01-01

353

16 CFR 680.2 - Examples.  

Code of Federal Regulations, 2011 CFR

... 680.2 Section 680.2 Commercial Practices FEDERAL TRADE COMMISSION THE FAIR CREDIT REPORTING ACT AFFILIATE MARKETING § 680.2 Examples. The examples in this part are not exclusive. Compliance with an example, to the...

2011-01-01

354

Thirty New Low-mass Spectroscopic Binaries  

Microsoft Academic Search

As part of our search for young M dwarfs within 25 pc, we acquired high-resolution spectra of 185 low-mass stars compiled by the NStars project that have strong X-ray emission. By cross-correlating these spectra with radial velocity standard stars, we are sensitive to finding multi-lined spectroscopic binaries. We find a low-mass spectroscopic binary fraction of 16% consisting of 27 SB2s,

Evgenya L. Shkolnik; Leslie Hebb; Michael C. Liu; I. Neill Reid; Andrew Collier Cameron

2010-01-01

355

Handbook of Basic Atomic Spectroscopic Data  

National Institute of Standards and Technology Data Gateway

SRD 108 Handbook of Basic Atomic Spectroscopic Data (Web, free access)   This handbook provides a selection of the most important and frequently used atomic spectroscopic data. The compilation includes data for the neutral and singly-ionized atoms of all elements hydrogen through einsteinium (Z = 1-99). The wavelengths, intensities, and spectrum assignments are given for each element, and the data for the approximately 12,000 lines of all elements are also collected into a single table.

356

Spectroscopic characterization of streptavidin functionalized quantum dots  

Microsoft Academic Search

The spectroscopic properties of quantum dots can be strongly influenced by the conditions of their synthesis. In this work, we have characterized several spectroscopic properties of commercial, streptavidin functionalized quantum dots (QD525, lot 1005-0045, and QD585, lot 0905-0031, from Invitrogen). This is the first step in the development of calibration beads to be used in a generalizable quantification scheme of

Yang Wu; Gabriel P. Lopez; Larry A. Sklar; Tione Buranda

2007-01-01

357

Very Large Spectroscopic Surveys with the VLT  

E-print Network

Recently, it has been recognised that very large spectroscopic surveys (several million spectra) are required to advance our understanding of Dark Energy (via baryonic wiggles) and the detailed history of our Local Group of galaxies (via Galactic Archeology or near-field cosmology). In this paper I make a preliminary exploration of how this might be done by putting a wide field, optical, prime-focus fibre-fed spectroscopic facility on one of the VLT's UTs.

Ian R. Parry

2008-03-26

358

Galaxy Evolution Spectroscopic Explorer (GESE)  

NASA Astrophysics Data System (ADS)

One of the key goals of NASA's astrophysics program is to answer the question: How did galaxies evolve into the spiral, elliptical, and irregular galaxies that we see today? We know that the star-formation rate density reached a peak at redshift, z~1.9, and then declined to the modest level of today, but we don't know what the physical processes were that drove galaxy evolution in the critical z=1-2 era. To fully understand galaxy evolution requires spectra in the rest-frame far-UV, a spectral region that is rich in diagnostics of young, massive stars, ionized nebulae, and the interstellar medium. Such spectra are beyond the reach of ground-based telescopes. We are therefore developing a space-telescope concept called Galaxy Evolution Spectroscopic Explorer (GESE), which will fill the z~1-2 gap by surveying the rest-frame far-UV spectra of 105 star-forming galaxies. When combined with optical-NIR spectra of the same galaxies from the Subaru Prime Focus Spectrograph and other telescopes, GESE spectra will enable us to track the properties of star-forming galaxies at all redshifts using the same spectral diagnostics. GESE spectra will thus enable us to identify the main drivers of galaxy evolution in the critical z=0.8-2 era (age of universe 3.3-6.8 Gyr).

Heap, Sara R.; Hull, Anthony B.; Purves, Lloyd R.

2015-01-01

359

Vibrational spectroscopic characterization of fluoroquinolones  

NASA Astrophysics Data System (ADS)

Quinolones are important gyrase inhibitors. Even though they are used as active agents in many antibiotics, the detailed mechanism of action on a molecular level is so far not known. It is of greatest interest to shed light on this drug-target interaction to provide useful information in the fight against growing resistances and obtain new insights for the development of new powerful drugs. To reach this goal, on a first step it is essential to understand the structural characteristics of the drugs and the effects that are caused by the environment in detail. In this work we report on Raman spectroscopical investigations of a variety of gyrase inhibitors (nalidixic acid, oxolinic acid, cinoxacin, flumequine, norfloxacin, ciprofloxacin, lomefloxacin, ofloxacin, enoxacin, sarafloxacin and moxifloxacin) by means of micro-Raman spectroscopy excited with various excitation wavelengths, both in the off-resonance region (532, 633, 830 and 1064 nm) and in the resonance region (resonance Raman spectroscopy at 244, 257 and 275 nm). Furthermore DFT calculations were performed to assign the vibrational modes, as well as for an identification of intramolecular hydrogen bonding motifs. The effect of small changes in the drug environment was studied by adding successively small amounts of water until physiological low concentrations of the drugs in aqueous solution were obtained. At these low concentrations resonance Raman spectroscopy proved to be a useful and sensitive technique. Supplementary information was obtained from IR and UV/vis spectroscopy.

Neugebauer, U.; Szeghalmi, A.; Schmitt, M.; Kiefer, W.; Popp, J.; Holzgrabe, U.

2005-05-01

360

Truly random number generation: an example  

NASA Astrophysics Data System (ADS)

Randomness is crucial for a variety of applications, ranging from gambling to computer simulations, and from cryptography to statistics. However, many of the currently used methods for generating randomness do not meet the criteria that are necessary for these applications to work properly and safely. A common problem is that a sequence of numbers may look random but nevertheless not be truly random. In fact, the sequence may pass all standard statistical tests and yet be perfectly predictable. This renders it useless for many applications. For example, in cryptography, the predictability of a "andomly" chosen password is obviously undesirable. Here, we review a recently developed approach to generating true | and hence unpredictable | randomness.

Frauchiger, Daniela; Renner, Renato

2013-10-01

361

Improved Spectroscopic Parameters for Transiting Planet Hosts  

NASA Astrophysics Data System (ADS)

We report homogeneous spectroscopic determinations of the effective temperature, metallicity, and projected rotational velocity for the host stars of 56 transiting planets. Our analysis is based primarily on the stellar parameter classification (SPC) technique. We investigate systematic errors by examining subsets of the data with two other methods that have often been used in previous studies (Spectroscopy Made Easy (SME) and MOOG). The SPC and SME results, both based on comparisons between synthetic spectra and actual spectra, show strong correlations between T eff, [Fe/H], and log g when solving for all three quantities simultaneously. In contrast the MOOG results, based on a more traditional curve-of-growth approach, show no such correlations. To combat the correlations and improve the accuracy of the temperatures and metallicities, we repeat the SPC analysis with a constraint on log g based on the mean stellar density that can be derived from the analysis of the transit light curves. Previous studies that have not taken advantage of this constraint have been subject to systematic errors in the stellar masses and radii of up to 20% and 10%, respectively, which can be larger than other observational uncertainties, and which also cause systematic errors in the planetary mass and radius.

Torres, Guillermo; Fischer, Debra A.; Sozzetti, Alessandro; Buchhave, Lars A.; Winn, Joshua N.; Holman, Matthew J.; Carter, Joshua A.

2012-10-01

362

Integrated Capture and Spectroscopic Detection of Viruses?  

PubMed Central

The goal of this work is to develop an online monitoring scheme for detection of viruses in flowing drinking water. The approach applies an electrodeposition process that is similar to the use of charged membrane filters previously employed for collection of viruses from aqueous samples. In the present approach, charged materials are driven onto a robust optical sensing element which has high transparency to infrared light. A spectroscopic measurement is performed using the evanescent wave that penetrates no more than 1 ?m from the surface of an infrared optical element in an attenuated total reflectance measurement scheme. The infrared measurement provides quantitative information on the amount and identity of material deposited from the water. Initial studies of this sensing scheme used proteins reversibly electrodeposited onto germanium chips. The results of those studies were applied to design a method for collection of viruses onto an attenuated total reflectance crystal. Spectral signatures can be discriminated between three types of protein and two viruses. There is the potential to remove deposited material by reversing the voltage polarity. This work demonstrates a novel and practical scheme for detection of viruses in water systems with potential application to near-continual, automated monitoring of municipal drinking water. PMID:19700543

Vargas, Crystal A.; Wilhelm, Allison A.; Williams, Jeremy; Lucas, Pierre; Reynolds, Kelly A.; Riley, Mark R.

2009-01-01

363

Semiclassical mean-trajectory approximation for nonlinear spectroscopic response functions.  

PubMed

Observables in nonlinear and multidimensional infrared spectroscopy may be calculated from nonlinear response functions. Numerical challenges associated with the fully quantum-mechanical calculation of these dynamical response functions motivate the development of semiclassical methods based on the numerical propagation of classical trajectories. The Herman-Kluk frozen Gaussian approximation to the quantum propagator has been demonstrated to produce accurate linear and third-order spectroscopic response functions for thermal ensembles of anharmonic oscillators. However, the direct application of this propagator to spectroscopic response functions is numerically impractical. We analyze here the third-order response function with Herman-Kluk dynamics with the two related goals of understanding the origins of the success of the approximation and developing a simplified representation that is more readily implemented numerically. The result is a semiclassical approximation to the nth-order spectroscopic response function in which an integration over n pairs of classical trajectories connected by distributions of discontinuous transitions is collapsed to a single phase-space integration, in which n continuous trajectories are linked by deterministic transitions. This significant simplification is shown to retain a full description of quantum effects. PMID:19045039

Gruenbaum, Scott M; Loring, Roger F

2008-09-28

364

EXAMPLES OF RADIATION SHIELDING MODELS  

SciTech Connect

The attached pictures are examples of shielding models used by WSMS. The models were used in shielding evaluations for Tank 50 pump replacement. They show the relative location of shielding to radiation sources for pumps and pipes. None of the calculations that were associated with these models involved UCNI. The last page contains two pictures from a shielding calculation for the saltstone area. The upper picture is a conceptual drawing. The lower picture is an image copied from the website of a supplier for the project.

Willison, J

2006-07-27

365

Atmospheric and Spectroscopic Research in the Far Infrared  

NASA Technical Reports Server (NTRS)

The spectroscopic measurements of molecular parameters constitute one of the major areas of our research program. This part of our program has been conducted in close collaboration with Smithsonian Astrophysical Observatory (SAO) and National Institute of Standards and Technology (NIST). The references on HO2, OH, and O2 that appear on the publication list are examples of this type of work completed during the grant period. These pressure-broadening studies have provided the kind of improvements needed in the database for retrieving atmospheric profiles from far infrared limb sensing data. Authors summarized the laboratory spectroscopic studies conducted during the grant period. We attempted to measure the pressure broadening coefficients of the O2 lines in the 50 and 117/ cm regions. An accurate characterization of these lines using the IBEX detector system was needed to analyze the flight data. These are difficult lines to measure because they arise from weak magnetic dipole transitions. We used a 4-meter absorption cell to obtain the pressure broadening coefficients for the 50 and 83 /cm lines. We also completed the pressure broadening studies including the temperature dependence of two lines of OH at 83 and 118 /cm. These two lines are important not only for the balloon data retrieval work but also for the future project proposals.Another area of focus in our program is the far infrared detector research. The third area of focus deals with data distribution and dissemination.

Park, Kwangjai

1998-01-01

366

Application of a New Non-Linear Least Squares Velocity Curve Analysis Technique for Spectroscopic Binary Stars  

E-print Network

Using measured radial velocity data of nine double lined spectroscopic binary systems NSV 223, AB And, V2082 Cyg, HS Her, V918 Her, BV Dra, BW Dra, V2357 Oph, and YZ Cas, we find corresponding orbital and spectroscopic elements via the method introduced by Karami & Mohebi (2007a) and Karami & Teimoorinia (2007). Our numerical results are in good agreement with those obtained by others using more traditional methods.

K. Karami; R. Mohebi; M. M. Soltanzadeh

2008-09-06

367

Spectroscopic Stokes polarimetry based on Fourier transform spectrometer  

NASA Astrophysics Data System (ADS)

Two methods are proposed for measuring the spectroscopic Stokes parameters using a Fourier transform spectrometer. In the first method, it is designed for single point measurement. The parameters are extracted using an optical setup comprising a white light source, a polarizer set to 0°, a quarter-wave plate and a scanning Michelson interferometer. In the proposed approach, the parameters are extracted from the intensity distributions of the interferograms produced with the quarter-wave plate rotated to 0°, 22.5°, 45° and -45°, respectively. For the second approach, the full-field and dynamic measurement can be designed based upon the first method with special angle design in a polarizer and a quarter-wave plate. Hence, the interferograms of two-dimensional detection also can be simultaneously extracted via a pixelated phase-retarder and polarizer array on a high-speed CCD camera and a parallel read-out circuit with a multi-channel analog to digital converter. Thus, a full-field and dynamic spectroscopic Stokes polarimetry without any rotating components could be developed. The validity of the proposed methods is demonstrated both numerically and experimentally. To the authors' knowledge, this could be the simplest optical arrangement in extracting the spectral Stokes parameters. Importantly, the latter one method avoids the need for rotating components within the optical system and therefore provides an experimentally straightforward means of extracting the dynamic spectral Stokes parameters.

Liu, Yeng-Cheng; Lo, Yu-Lung; Li, Chang-Ye; Liao, Chia-Chi

2015-02-01

368

Combining Spectroscopic and Photometric Surveys: Same or different sky?  

E-print Network

This article looks at the combined constraints from a photometric and spectroscopic survey. These surveys will measure cosmology using weak lensing (WL), galaxy cluster- ing, baryon acoustic oscillations (BAO) and redshift space distortions (RSD). We find, contrary to some findings in the recent literature, that overlapping surveys can give important benefits when measuring dark energy. We therefore try to clarify the status of this issue with a full forecast of two stage-IV surveys using a new approach to prop- erly account for covariance between the different probes in the overlapping samples. The benefit of the overlapping survey can be traced back to two factors: additional observables and sample variance cancellation. Both needs to be taken into account and contribute equally when combining 3D power spectrum and 2D correlations for lensing. With an analytic example we also illustrate that for optimal constraints, one should minimize the (Pearson) correlation coefficient between cosmological and nui- sanc...

Eriksen, Martin

2014-01-01

369

On determining dose rate constants spectroscopically  

SciTech Connect

Purpose: To investigate several aspects of the Chen and Nath spectroscopic method of determining the dose rate constants of {sup 125}I and {sup 103}Pd seeds [Z. Chen and R. Nath, Phys. Med. Biol. 55, 6089-6104 (2010)] including the accuracy of using a line or dual-point source approximation as done in their method, and the accuracy of ignoring the effects of the scattered photons in the spectra. Additionally, the authors investigate the accuracy of the literature's many different spectra for bare, i.e., unencapsulated {sup 125}I and {sup 103}Pd sources. Methods: Spectra generated by 14 {sup 125}I and 6 {sup 103}Pd seeds were calculated in vacuo at 10 cm from the source in a 2.7 Multiplication-Sign 2.7 Multiplication-Sign 0.05 cm{sup 3} voxel using the EGSnrc BrachyDose Monte Carlo code. Calculated spectra used the initial photon spectra recommended by AAPM's TG-43U1 and NCRP (National Council of Radiation Protection and Measurements) Report 58 for the {sup 125}I seeds, or TG-43U1 and NNDC(2000) (National Nuclear Data Center, 2000) for {sup 103}Pd seeds. The emitted spectra were treated as coming from a line or dual-point source in a Monte Carlo simulation to calculate the dose rate constant. The TG-43U1 definition of the dose rate constant was used. These calculations were performed using the full spectrum including scattered photons or using only the main peaks in the spectrum as done experimentally. Statistical uncertainties on the air kerma/history and the dose rate/history were Less-Than-Or-Slanted-Equal-To 0.2%. The dose rate constants were also calculated using Monte Carlo simulations of the full seed model. Results: The ratio of the intensity of the 31 keV line relative to that of the main peak in {sup 125}I spectra is, on average, 6.8% higher when calculated with the NCRP Report 58 initial spectrum vs that calculated with TG-43U1 initial spectrum. The {sup 103}Pd spectra exhibit an average 6.2% decrease in the 22.9 keV line relative to the main peak when calculated with the TG-43U1 rather than the NNDC(2000) initial spectrum. The measured values from three different investigations are in much better agreement with the calculations using the NCRP Report 58 and NNDC(2000) initial spectra with average discrepancies of 0.9% and 1.7% for the {sup 125}I and {sup 103}Pd seeds, respectively. However, there are no differences in the calculated TG-43U1 brachytherapy parameters using either initial spectrum in both cases. Similarly, there were no differences outside the statistical uncertainties of 0.1% or 0.2%, in the average energy, air kerma/history, dose rate/history, and dose rate constant when calculated using either the full photon spectrum or the main-peaks-only spectrum. Conclusions: Our calculated dose rate constants based on using the calculated on-axis spectrum and a line or dual-point source model are in excellent agreement (0.5% on average) with the values of Chen and Nath, verifying the accuracy of their more approximate method of going from the spectrum to the dose rate constant. However, the dose rate constants based on full seed models differ by between +4.6% and -1.5% from those based on the line or dual-point source approximations. These results suggest that the main value of spectroscopic measurements is to verify full Monte Carlo models of the seeds by comparison to the calculated spectra.

Rodriguez, M.; Rogers, D. W. O. [Carleton Laboratory for Radiotherapy Physics, Carleton University, Ottawa K1S 5B6 (Canada)

2013-01-15

370

Two examples from chemical physics  

SciTech Connect

Now that parallel vector processors are replacing scalar processors as a computational tool, scientists must reexamine the efficiency of existing code. The algorithms used and the code developed on scalar machines should be replaced by codes optimized for vector and parallel machines. New codes adapted to parallel computing should be written for a whole range of problems in chemistry and physics. Because most scientific application programs are - and will probably continue to be - written in Fortran, we will have to rely on Fortran as a programming language for supercomputers. Extensions of Fortran 77, usually referred to as Fortran 8X, are being discussed. These changes - for example, operations on whole vectors expressed in one statement - would incorporate instructions tailored to machines with parallel architectures. However, we are still a long way from setting and implementing a standard for general use. In fact, the proliferation of different vector processors and architectures could create a jungle of new Fortran hybrids, a highly unsatisfactory situation.

Wallqvist, A.; Berne, B.J.; Pangali, C.

1987-05-01

371

Testing of numerical methods, convective schemes, algorithms for approximation of flows, and grid structures by the example of a supersonic flow in a step-shaped channel with the use of the CFX and fluent packages  

Microsoft Academic Search

An unsteady supersonic flow of a nonviscous gas with a Mach number M = 3 in a step-shaped channel has been calculated. The\\u000a accuracy of the forecasts made has been analyzed on the basis of the Roe dissipation model and the advective upwind splitting\\u000a method with the use of convective schemes of the second and third orders of accuracy and

S. A. Isaev; D. A. Lysenko

2009-01-01

372

NIR spectroscopic method for the in-line moisture assessment during drying in a six-segmented fluid bed dryer of a continuous tablet production line: Validation of quantifying abilities and uncertainty assessment.  

PubMed

This study focuses on the thorough validation of an in-line NIR based moisture quantification method in the six-segmented fluid bed dryer of a continuous from-powder-to-tablet manufacturing line (ConsiGma™ 25, GEA Pharma Systems nv, Wommelgem, Belgium). The moisture assessment ability of an FT-NIR spectrometer (Matrix™-F Duplex, Bruker Optics Ltd, UK) equipped with a fiber-optic Lighthouse Probe™ (LHP, GEA Pharma Systems nv, Wommelgem, Belgium) was investigated. Although NIR spectroscopy is a widely used technique for in-process moisture determination, a minority of NIR spectroscopy methods is thoroughly validated. A moisture quantification PLS model was developed. Twenty calibration experiments were conducted, during which spectra were collected at-line and then regressed versus the corresponding residual moisture values obtained via Karl Fischer measurements. The developed NIR moisture quantification model was then validated by calculating the accuracy profiles on the basis of the analysis results of independent in-line validation experiments. Furthermore, as the aim of the NIR method is to replace the destructive, time-consuming Karl Fischer titration, it was statistically demonstrated that the new NIR method performs at least as good as the Karl Fischer reference method. PMID:25124155

Fonteyne, Margot; Arruabarrena, Julen; de Beer, Jacques; Hellings, Mario; Van Den Kerkhof, Tom; Burggraeve, Anneleen; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas

2014-11-01

373

Spectroscopic and dynamical studies of highly energized small polyatomic molecules  

NASA Astrophysics Data System (ADS)

Stimulated emission pumping (SEP) spectroscopy was used on acetylene and on formyl radical. An attempt was made for pattern recognition based on statistics; a method was invented that combined CNPI (complete nuclear permutation-inversion) group theory and SCC (spectral cross-correlation). But the direction away from statistical pattern recognition back to traditional spectroscopic pattern recognition was taken. Vibrational states and quantum numbers are discussed. For the formyl radical, the fluorescence excitation spectrum was recorded and a rotational analysis of the 0(sup 0)(sub 0) band performed.

374

Spectroscopic Feedback for High Density Data Storage and Micromachining  

DOEpatents

Optical breakdown by predetermined laser pulses in transparent dielectrics produces an ionized region of dense plasma confined within the bulk of the material. Such an ionized region is responsible for broadband radiation that accompanies a desired breakdown process. Spectroscopic monitoring of the accompanying light in real-time is utilized to ascertain the morphology of the radiated interaction volume. Such a method and apparatus as presented herein, provides commercial realization of rapid prototyping of optoelectronic devices, optical three-dimensional data storage devices, and waveguide writing.

Carr, Christopher W. (Livermore, CA); Demos, Stavros (Livermore, CA); Feit, Michael D. (Livermore, CA); Rubenchik, Alexander M. (Livermore, CA)

2008-09-16

375

The use and generation of illustrative examples in computer-based instructional systems  

NASA Technical Reports Server (NTRS)

A method is proposed whereby the underlying domain knowledge is represented such that illustrative examples may be generated on demand. This method has the advantage that the generated example can follow changes in the domain in addition to allowing automatic customization of the example to the individual.

Selig, William John; Johannes, James D.

1987-01-01

376

Quantum mechanical study and spectroscopic (FT-IR, FT-Raman, 13C, 1H) study, first order hyperpolarizability, NBO analysis, HOMO and LUMO analysis of 2-acetoxybenzoic acid by density functional methods  

NASA Astrophysics Data System (ADS)

In this work, colorless crystals of 2-acetoxybenzoic acid were grown by slow evaporation method and the FT-IR and FT-Raman spectra of the sample were recorded in the region 4000-500 cm-1 and 4000-100 cm-1 respectively. Molecular structure is optimized with the help of density functional theory method (B3LYP) with 6-31+G(d,p), 6-311++G(d,p) basis sets. Stability of the molecule arising from hyperconjugation and charge delocalization is confirmed by the natural bond orbital analysis (NBO). The results show that electron density (ED) in the ?? antibonding orbitals and E(2) energies confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. The assignments of the vibrational spectra have been carried out with the help of normal coordinate analysis following the scaled quantum mechanical force field (SQMFF) methodology. The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by GIAO method. Mulliken population analysis on atomic charges is also calculated. The calculated HOMO and LUMO energy gap shows that charge transfer occurs within the molecule.

Bhavani, K.; Renuga, S.; Muthu, S.; Sankara narayanan, K.

2015-02-01

377

Quantum mechanical study and spectroscopic (FT-IR, FT-Raman, (13)C, (1)H) study, first order hyperpolarizability, NBO analysis, HOMO and LUMO analysis of 2-acetoxybenzoic acid by density functional methods.  

PubMed

In this work, colorless crystals of 2-acetoxybenzoic acid were grown by slow evaporation method and the FT-IR and FT-Raman spectra of the sample were recorded in the region 4000-500cm(-1) and 4000-100cm(-1) respectively. Molecular structure is optimized with the help of density functional theory method (B3LYP) with 6-31+G(d,p), 6-311++G(d,p) basis sets. Stability of the molecule arising from hyperconjugation and charge delocalization is confirmed by the natural bond orbital analysis (NBO). The results show that electron density (ED) in the ?(?) antibonding orbitals and E(2) energies confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. The assignments of the vibrational spectra have been carried out with the help of normal coordinate analysis following the scaled quantum mechanical force field (SQMFF) methodology. The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by GIAO method. Mulliken population analysis on atomic charges is also calculated. The calculated HOMO and LUMO energy gap shows that charge transfer occurs within the molecule. PMID:25456668

Bhavani, K; Renuga, S; Muthu, S; Sankara Narayanan, K

2014-10-15

378

Rapid identification of single microbes by various Raman spectroscopic techniques  

NASA Astrophysics Data System (ADS)

A fast and unambiguous identification of microorganisms is necessary not only for medical purposes but also in technical processes such as the production of pharmaceuticals. Conventional microbiological identification methods are based on the morphology and the ability of microbes to grow under different conditions on various cultivation media depending on their biochemical properties. These methods require pure cultures which need cultivation of at least 6 h but normally much longer. Recently also additional methods to identify bacteria are established e.g. mass spectroscopy, polymerase chain reaction (PCR), flow cytometry or fluorescence spectroscopy. Alternative approaches for the identification of microorganisms are vibrational spectroscopic techniques. With Raman spectroscopy a spectroscopic fingerprint of the microorganisms can be achieved. Using UV-resonance Raman spectroscopy (UVRR) macromolecules like DNA/RNA and proteins are resonantly enhanced. With an excitation wavelength of e.g. 244 nm it is possible to determine the ratio of guanine/cytosine to all DNA bases which allows a genotypic identification of microorganisms. The application of UVRR requires a large amount of microorganisms (> 10 6 cells) e.g. at least a micro colony. For the analysis of single cells micro-Raman spectroscopy with an excitation wavelength of 532 nm can be used. Here, the obtained information is from all type of molecules inside the cells which lead to a chemotaxonomic identification. In this contribution we show how wavelength dependent Raman spectroscopy yields significant molecular information applicable for the identification of microorganisms on a single cell level.

Rösch, Petra; Harz, Michaela; Schmitt, Michael; Peschke, Klaus-Dieter; Ronneberger, Olaf; Burkhardt, Hans; Motzkus, Hans-Walter; Lankers, Markus; Hofer, Stefan; Thiele, Hans; Popp, Jürgen

2006-02-01

379

Non-observability of Spectroscopic Factors  

E-print Network

The spectroscopic factor has long played a central role in nuclear reaction theory. However, it is not an observable. Consequently it is of minimal use as a meeting point between theory and experiment. In this paper the nature of the problem is explored. At the many-body level, unitary transformations are constructed that vary the spectroscopic factors over the full range of allowed values. At the phenomenological level, field redefinitions play a similar role and the spectroscopic factor extracted from experiment depend more on the assumed energy dependence of the potentials than on the measured cross-sections. The consistency conditions, gauge invariance and Wegmann's theorem play a large role in these considerations.

B. K. Jennings

2011-02-17

380

Spectroscopic studies in open quantum systems  

E-print Network

The spectroscopic properties of an open quantum system are determined by the eigenvalues and eigenfunctions of an effective Hamiltonian H consisting of the Hamiltonian H_0 of the corresponding closed system and a non-Hermitian correction term W arising from the interaction via the continuum of decay channels. The eigenvalues E_R of H are complex. They are the poles of the S-matrix and provide both the energies and widths of the states. We illustrate the interplay between Re(H) and Im(H) by means of the different interference phenomena between two neighboured resonance states. Level repulsion along the real axis appears if the interaction is caused mainly by Re(H) while a bifurcation of the widths appears if the interaction occurs mainly due to Im(H). We then calculate the poles of the S-matrix and the corresponding wavefunctions for a rectangular microwave resonator with a scatter as a function of the area of the resonator as well as of the degree of opening to a guide. The calculations are performed by using the method of exterior complex scaling. Re(W) and Im(W) cause changes in the structure of the wavefunctions which are permanent, as a rule. At full opening to the lead, short-lived collective states are formed together with long-lived trapped states. The wavefunctions of the short-lived states at full opening to the lead are very different from those at small opening. The resonance picture obtained from the microwave resonator shows all the characteristic features known from the study of many-body systems in spite of the absence of two-body forces. The poles of the S-matrix determine the conductance of the resonator. Effects arising from the interplay between resonance trapping and level repulsion along the real axis are not involved in the statistical theory.

I. Rotter; E. Persson; K. Pichugin; P. Seba

2000-02-14

381

Self-Organizing Example-Based Machine Translation, A Prototype.  

ERIC Educational Resources Information Center

This paper describes an attempt to combine the advantages of both example-based translation and stochastic translation methods in an attempt to develop a method for inferring symbolic transfer functions from a bilingual corpus. By formalizing the translation process and applying standard optimization techniques, a system can be developed that will…

Juola, Patrick

382

A new insight into the observation of spectroscopic strength reduction in atomic nuclei: implication for the physical meaning of spectroscopic factors  

E-print Network

Experimental studies of one nucleon knockout from magic nuclei suggest that their nucleon orbits are not fully occupied. This conflicts a commonly accepted view of the shell closure associated with such nuclei. The conflict can be reconciled if the overlap between initial and final nuclear states in a knockout reaction are calculated by a non-standard method. The method employs an inhomogeneous equation based on correlation-dependent effective nucleon-nucleon (NN) interactions and allows the simplest wave functions, in which all nucleons occupy only the lowest nuclear orbits, to be used. The method also reproduces the recently established relation between reduction of spectroscopic strength, observed in knockout reactions on other nuclei, and nucleon binding energies. The implication of the inhomogeneous equation method for the physical meaning of spectroscopic factors is discussed.

N. K. Timofeyuk

2009-11-26

383

Continuum coupling and spectroscopic properties of nuclei  

E-print Network

The nucleus is a correlated open quantum many-body system. The presence of states that are unbound to particle emission may have significant impact on spectroscopic properties of nuclei, especially those close to the particle drip lines. In the framework of the continuum shell model in the complex momentum-plane, we discuss salient effects of the continuum coupling on the spectroscopic factors, one-neutron overlap integrals, and energies of excited states in $^{6}$He and $^{18}$O. We demonstrate the presence of non-perturbative threshold effects in many-body wave functions of weakly-bound and unbound states.

N. Michel; W. Nazarewicz; M. Ploszajczak; J. Rotureau

2006-01-18

384

Theoretical spectroscopic parameters for the low-lying states of the second-row transition metal hydrides  

SciTech Connect

Spectroscopic parameters (D/sub e/,r/sub e/,..mu../sub e/) are determined for the second-row transition metal hydrides using large valence basis sets in conjunction with relativistic effective core potentials (RECPs). All-electron calculations are also performed for YH and AgH to calibrate the RECP results. Electron correlation is incorporated using singles-plus-doubles configuration interaction (SDCI), the coupled pair functional (CPF) method, and a modified version (MCPF) of CPF. Although similarities exist between the bonding in the first- and second-row transition metal hydrides, the greater overlap of the d orbitals in the second row with the hydrogen 1s orbital, tends to lead to larger dissociation energies and some changes in the relative ordering of the states. For example, the ground state of ZrH is predicted to be a /sup 2/..delta.. state whose bonding involves 4d--5s hybrid orbitals, whereas in TiH the ground state is a /sup 4/Phi state with primarily 4s--1s bonding. The bonding in the second-row transition metal hydrides involves a mixture of all three atomic asymptotes, 4d/sup n/5s/sup 2/, 4d/sup n//sup +1/5s/sup 1/, and 4d/sup n//sup +2/, whereas contribution from the 3d/sup n//sup +2/ asymptote is unimportant in the first-row TM hydrides. However, the bonding is generally much simpler to describe in the second-row as compared with the first-row TM hydrides, and the spectroscopic parameters are much less sensitive to the level of correlation treatment.

Langhoff, S.R.; Pettersson, L.G.M.; Bauschlicher C.W. Jr.; Partridge, H.

1987-01-01

385

Density Ratio Examples Semiparametric Statistical Formulation  

E-print Network

UMinformal Density Ratio Examples Semiparametric Statistical Formulation Combined semiparametric density estimators Semiparametric regression Application to Testicular Germ Cell Cancer Semiparametric Density Ratio Examples Semiparametric Statistical Formulation Combined semiparametric density estimators

Johnson, Raymond L.

386

Analog Computer Laboratory with Biological Examples.  

ERIC Educational Resources Information Center

The use of biological examples in teaching applications of the analog computer is discussed and several examples from mathematical ecology, enzyme kinetics, and tracer dynamics are described. (Author/GA)

Strebel, Donald E.

1979-01-01

387

Basic examples: Interactive Tutorial about Diffraction  

NSDL National Science Digital Library

Using images and text, this site from the University of Wuertzburg employs basic examples to familiarize students with the concept of structure simulations and Fourier transforms. The Fourier transforms of single atoms and small groups of atoms are calculated in one and two dimensions. Users can work through the examples first and then move on to the interactive simulation, or try running the simulations first and then verify their findings using the examples. Also included are links to interactive examples of diffraction.

Proffen, Th.; Neder, R. B.; Institute Of Mineralogy, University O.

388

Characterization by spectroscopic Ellipsometry, the physical properties of silver nanoparticles.  

NASA Astrophysics Data System (ADS)

Physicists are able to change their minds through their experiments. I think it is time to go kick the curse and go further in research if we want a human future. I work in the Nano-Optics and Plasmonics research. I defined with ellipsomètrie the structure of new type of Nano particles of silver. It's same be act quickly to replace the old dirty leaded electronic-connexion chip and by the other hand to find a new way for the heath care of cancer disease by nanoparticles the next killers of bad cells. Silver nanoparticle layers are obtained by Spark Plasma Sintering are investigated as an alternative to lead alloy based material for solder joint in power mechatronics modules. These layers are characterized by mean of conventional techniques that is the dilatometry technique, the resistivity measurement through the van der Pauw method, and the flash laser technique. Furthermore, the nanoparticles of silver layer are deeply studied by UV-Visible spectroscopic ellipsometry. Spectroscopic angles parameters are determined in function of temperature and dielectric constants are deduced and analyzed through an optical model which takes into account a Drude and a Lorentz component within the Bruggeman effective medium approximation (EMA). The relaxation times and the electrical conductivity are plot in function of temperature. The obtained electrical conductivity give significant result in good agreement to those reported by four points electrical measurement method.

Coanga, Jean-Maurice

2013-04-01

389

Copy to contiguous example using C descriptor  

SciTech Connect

In N1838-2 there is an example of how to use the CFI-cdesc-t type in a C implementation of a BIND (C) interface. This paper provides another example of using the CFI-cdesc-t type in C. This new example provides code to copy an array (possibly noncontiguous) into a contiguous buffer.

Rasmussen, Craig E [Los Alamos National Laboratory

2011-01-18

390

EAGER: programming repetitive tasks by example  

Microsoft Academic Search

Eager is a Programming by Example system for the HyperCard environment. It constantly monitors the user's activities, and when it detects an iterative pattern, it writes a program to complete the iteration. Programming by Example systems create generalized programs from examples provided by the user. They are faced with the problem of how to display these abstract procedures. Eager utilizes

Allen Cypher

1991-01-01

391

Derivation of the mass ratios of 20 new double-lined spectroscopic binaries  

NASA Astrophysics Data System (ADS)

The secondary component was detected in the spectra of 20 systems which were previously single-lined spectroscopic binaries (SB1s) with known orbital elements. The mass ratio of each new double-lined spectroscopic binary (SB2) was derived through two methods: (1) computation of an SB2 orbit using the old measurements of the radial velocity in addition to the new ones, and, (2) direct computation of the mass ratio from the variations of the radial velocities of the components. Some results are presented here.

Halbwachs, J.-L.; Arenou, F.; Pourbaix, D.; Famaey, B.; Guillout, P.; Lebreton, Y.; Salomon, J.-B.; Tal-Or, L.; Ibata, R.; Mazeh, T.

2014-12-01

392

The Electromagnetic Spectrum: Cereal Box Analytical Spectroscope  

NSDL National Science Digital Library

In this activity, students construct an analytical spectroscope and analyze the spectrum produced when various substances are heated or excited with electricity. This activity is part of Unit 2 in the Space Based Astronomy guide that contains background information, worksheets, assessments, extensions, and standards.

393

A spectroscopic test for substellar objects  

Microsoft Academic Search

We describe a spectroscopic test capable of providing direct confirmation of the substellar nature of brown dwarf candidates. While the conditions for substantial lithium burning are reached even in very low-mass stars, in substellar objects with less than 0.06 solar mass such conditions are never attained and Li is expected to be preserved. Therefore, the detection of lithium in the

Antonio Magazzu; Eduardo L. Martin; Rafael Rebolo

1993-01-01

394

Asiago spectroscopic classification of four SNe  

NASA Astrophysics Data System (ADS)

The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic observation of ASASSN-15ak, PSN J09411555+3553174, PSN J12543553-1234186, ASASSN-15ae, MASTER OT J021447.67+481852.6.

Tomasella, L.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Pastorello, A.; Tartaglia, L.; Terreran, G.; Turatto, M.

2015-01-01

395

On the lambda Bootis spectroscopic binary hypothesis  

E-print Network

It is still a matter of debate if the group of lambda Bootis stars is homogeneously defined. A widely discussed working hypothesis formulates that two apparent solar abundant stars of an undetected spectroscopic binary system mimic a single metal-weak spectrum preventing any reliable analysis of the group characteristics. Is the proposed spectroscopic binary model able to explain the observed abundance pattern and photometric metallicity indices for the group members? What is the percentage of undetected spectroscopic binary systems? We have used the newest available stellar atmospheres to synthesize 105 hypothetical binary systems in the relevant astrophysical parameter range. These models were used to derive photometric indices. As a test, values for single stellar atmospheres, Vega and two typical lambda Bootis stars, HD 107233 and HD 204041, were generated. The synthesized indices fit the standard lines and the observations of the three stars excellently. For about 90% of the group members, the spectroscopic inary hypothesis can not explain the observations. A carefully preselection of lambda Bootis stars results in a homogeneous group of objects which can be used to investigate the group characteristics.

Christian Stuetz; Ernst Paunzen

2006-09-05

396

The HITRAN 2008 molecular spectroscopic database  

Microsoft Academic Search

This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for

L. S. Rothman; I. E. Gordon; A. Barbe; D. Chris Benner; P. F. Bernath; M. Birk; V. Boudon; L. R. Brown; A. Campargue; J.-P. Champion; K. Chance; L. H. Coudert; V. Dana; V. M. Devi; S. Fally; J.-M. Flaud; R. R. Gamache; A. Goldman; D. Jacquemart; I. Kleiner; N. Lacome; W. J. Lafferty; J.-Y. Mandin; S. T. Massie; S. N. Mikhailenko; C. E. Miller; N. Moazzen-Ahmadi; O. V. Naumenko; A. V. Nikitin; J. Orphal; V. I. Perevalov; A. Perrin; A. Predoi-Cross; C. P. Rinsland; M. Rotger; M. Šime?ková; M. A. H. Smith; K. Sung; S. A. Tashkun; J. Tennyson; R. A. Toth; A. C. Vandaele; J. Vander Auwera

2009-01-01

397

EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION  

E-print Network

A rare eclipse of the mysterious object ? Aurigae will occur in 2009-2011. We report an updated single-lined spectroscopic solution for the orbit of the primary star based on 20 years of monitoring at the CfA, combined ...

Stefanik, Robert P.

398

Spectroscopic observation of the rotational Doppler effect  

E-print Network

We report on the first spectroscopic observation of the rotational Doppler shift associated with light beams carrying orbital angular momentum. The effect is evidenced as the broadening of a Hanle/EIT coherence resonance on Rb vapor when the two incident Laguerre-Gaussian laser beams have opposite topological charges. The observations closely agree with theoretical predictions.

S. Barreiro; J. W. R. Tabosa; H. Failache; A. Lezama

2006-07-26

399

The HITRAN 2004 molecular spectroscopic database  

Microsoft Academic Search

This paper describes the status of the 2004 edition of the HITRAN molecular spectroscopic database. The HITRAN compilation consists of several components that serve as input for radiative transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e., spectra in which the individual

L. S. Rothman; D. Jacquemart; A. Barbe; D. Chris Benner; M. Birk; L. R. Brown; M. R. Carleer; C CHACKERIANJR; K. Chance; L. H. Coudert; V. Dana; V. M. Devi; J.-M. Flaud; R. R. Gamache; A. Goldman; J.-M. Hartmann; K. W. Jucks; A. G. Maki; J.-Y. Mandin; S. T. Massie; J. Orphal; A. Perrin; C. P. Rinsland; M. A. H. Smith; J. Tennyson; R. N. Tolchenov; R. A. Toth; J. Vander Auwera; P. Varanasi; G. Wagner

2005-01-01

400

Asiago spectroscopic classification of six optical transients  

NASA Astrophysics Data System (ADS)

The Asiago Transient Classification Program (Tomasella et al. 2014, AN, 335, 841) reports the spectroscopic observation of the following transients. Targets were supplied by the Astronomy Section of the Rochester Academy of Sciences (arXiv:1103.5165), the CBAT Transient Objects Confirmation Page (TOCP) and the Gaia Photometric Science Alerts (validation phase).

Tomasella, L.; Benetti, S.; Cappellaro, E.; Elias-Rosa, N.; Ochner, P.; Pastorello, A.; Tartaglia, L.; Terreran, G.; Turatto, M.

2015-01-01

401

Challenge for spectroscopic tomography of biomembrane using imaging type two-dimensional Fourier spectroscopy  

NASA Astrophysics Data System (ADS)

We propose an image-producing Fourier spectroscopic technology that enables two-dimensional spectroscopic images to be obtained within the focusing plane alone. This technology incorporates auto-correlational phase-shift interferometry that uses only object light generated by the bright points that optically make up the object. We are currently involved in studies of non-invasive technologies used to measure blood components such as glucose and lipids, which are measured for use in daily living. Previous studies have investigated non-invasive technologies that measure blood glucose levels by utilizing near-infrared light that permeates the skin well. It has been confirmed that subtle changes in the concentration of a glucose solution, a sample used to measure the glucose level, can be measured by analyzing the spectroscopic characteristics of near-infrared light; however, when applied to a biomembrane, technology such as this is incapable of precisely measuring the glucose level because light diffusion within the skin disturbs the measurement. Our proposed technology enables two-dimensional spectroscopy to a limited depth below the skin covered by the measurement. Specifically, our technology concentrates only on the vascular territory near the skin surface, which is only minimally affected by light diffusion, as discussed previously; the spectroscopic characteristics of this territory are obtained and the glucose level can be measured with good sensitivity. In this paper we propose an image-producing Fourier spectroscopy method that is used as the measuring technology in producing a three-dimensional spectroscopic image.

Qi, Wei; Ishimaru, Ichiro

2010-02-01

402

Alzheimer Disease: Quantitative H-1 MR Spectroscopic Imaging of Frontoparietal Brain1  

PubMed Central

PURPOSE To replicate previous hydrogen-1 magnetic resonance (MR) spectroscopic imaging findings of metabolic abnormalities in patients with Alzheimer disease (AD), to verify that metabolic abnormalities are not an artifact of structural variations measured at MR imaging, to determine whether metabolic changes correlate with dementia severity, and to test whether MR imaging and MR spectroscopic imaging findings together improve ability to differentiate AD. MATERIALS AND METHODS MR spectroscopic imaging and MR imaging were performed in 28 patients with AD and 22 healthy elderly subjects. Spectroscopic imaging data were coregistered with MR imaging segmentation data to obtain volume-corrected metabolite concentrations. RESULTS Consistent with previous results, N-acetyl aspartate (NAA) levels were statistically significantly reduced in frontal and posterior mesial cortex of AD patients, presumably due to neuronal loss. NAA level reductions were independent of structural variations measured at MR imaging and, in parietal mesial cortex, were correlated mildly with dementia severity. Spectroscopic imaging findings of NAA level combined with MR imaging measures did not improve discrimination power for AD relative to that of MR imaging alone. CONCLUSION Reduced NAA levels in frontoparietal brain are of limited use for diagnosis of AD. However, they are not an artifact of structural variations and thus may provide useful information for the understanding of the pathologic processes underlying AD. PMID:9530304

Schuff, Norbert; Amend, Diane L.; Meyerhoff, Dieter J.; Tanabe, Jody L.; Norman, David; Fein, George; Weiner, Michael W.

2009-01-01

403

Stability of UV exposed RR-P3BT films by spectroscopic ellipsometry  

SciTech Connect

Stability of regioregular poly(3-butylthiophene) (RR-P3BT) films under irradiation of ultra-violet (UV) light has been studied by spectroscopic ellipsometry at room temperature. Consistent decrease in dielectric function with UV exposure time showed the degree of degradation of polymer. This work suggests that, protective methods are mandatory to use this kind of material in optical devices.

Diware, Mangesh S.; Byun, J. S.; Hwang, S. Y.; Kim, T. J.; Kim, Y. D. [Nano-Optical Property Laboratory and Department of Physics, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

2013-02-05

404

Chemical and spectroscopic analysis of organic matter transformations during composting of pig manure  

Microsoft Academic Search

Composting of separated pig manure (SPM) was studied in an attempt to elaborate upon organic matter (OM) transformation during the process and define parameters for product maturity using both chemical and spectroscopical methods. Composting was performed in two piles and the following parameters were measured in 10 samples during 122 days of composting: temperature, ash content, C\\/N ratio, water-soluble organic

Jenn-Hung Hsu; Shang-Lien Lo

1999-01-01

405

The passivation of vanadium contaminants in model fluid cracking catalysts (FCC): Spectroscopic studies  

Microsoft Academic Search

This paper reviews literature data on model fluid cracking catalysts (FCC) and reports results of spectroscopic studies performed in their laboratories for catalysts in which vanadium has been passivated by tin. Moessbauer spectroscopy, luminescence, X-ray powder diffraction and electron paramagnetic methods have been used to monitor vanadium-tin interactions in all the catalysts studied.

S. L. Suib; M. W. Anderson; M. L. Occelli

1988-01-01

406

Combined magnetic resonance imaging and spectroscopic imaging approach to molecular imaging of prostate cancer  

Microsoft Academic Search

Magnetic resonance spectroscopic imaging (MRSI) provides a noninvasive method of detecting small molecular mark- ers (historically the metabolites choline and citrate) within the cytosol and extracellular spaces of the prostate, and is performed in conjunction with high-resolution anatomic imaging. Recent studies in pre-prostatectomy patients have indicated that the metabolic information provided by MRSI combined with the anatomical information provided by

John Kurhanewicz; Mark G. Swanson; Sarah J. Nelson; Daniel B. Vigneron

2002-01-01

407

Spectroscopic Properties of Colloidal Indium Phosphide Quantum Wires Fudong Wang,  

E-print Network

Spectroscopic Properties of Colloidal Indium Phosphide Quantum Wires Fudong Wang,§ Heng Yu,§ Jingbo, 2007. E-mail: buhro@wustl.edu. Title running head: Spectroscopic Properties of InP Quantum Wires spectroscopically, are compared to the results of various theoretical analyses, and to previous experimental values

Geddes, Cameron Guy Robinson

408

Quantum mechanical study and spectroscopic (FT-IR, FT-Raman, UV-Visible) study, potential energy surface scan, Fukui function analysis and HOMO-LUMO analysis of 3-tert-butyl-4-methoxyphenol by DFT methods.  

PubMed

This study represents an integral approach towards understanding the electronic and structural aspects of 3-tert-butyl-4-methoxyphenol (TBMP). Fourier-transform Infrared (FT-IR) and Fourier-transform Raman (FT-Raman) spectra of TBMP was recorded in the region 4000-400 cm(-1) and 3500-100 cm(-1), respectively. The molecular structures, vibrational wavenumbers, infrared intensities and Raman activities were calculated using DFT (B3LYP and LSDA) methods using 6-311++G (d,p) basis set. The most stable conformer of TBMP was identified from the computational results. The assignments of vibrational spectra have been carried out with the help of normal co-ordinate analysis (NCA) following the scaled quantum mechanical force field (SQMFF) methodology. The first order hyperpolarizability (?0) and related properties (?, ?0 and ??) of TBMP have been discussed. The stability and charge delocalization of the molecule was studied by Natural Bond Orbital (NBO) analysis. UV-Visible spectrum and effects of solvents have been discussed and the electronic properties such as HOMO and LUMO energies were determined by time-dependent TD-DFT approach with B3LYP/6-311++G (d,p) level of theory. The molecule orbital contributions are studied by density of energy states (DOSs). The reactivity sites are identified by mapping the electron density into electrostatic potential surface (MEP). Mulliken analysis of atomic charges is also calculated. The thermodynamic properties at different temperatures were calculated, revealing the correlations between standard heat capacities, standard entropy and standard enthalpy changes with temperatures. Global hardness, global softness, global electrophilicity and ionization potential of the title compound are determined. PMID:24813291

Saravanan, S; Balachandran, V

2014-09-15

409

Quantum mechanical study and spectroscopic (FT-IR, FT-Raman, UV-Visible) study, potential energy surface scan, Fukui function analysis and HOMO-LUMO analysis of 3-tert-butyl-4-methoxyphenol by DFT methods  

NASA Astrophysics Data System (ADS)

This study represents an integral approach towards understanding the electronic and structural aspects of 3-tert-butyl-4-methoxyphenol (TBMP). Fourier-transform Infrared (FT-IR) and Fourier-transform Raman (FT-Raman) spectra of TBMP was recorded in the region 4000-400 cm-1 and 3500-100 cm-1, respectively. The molecular structures, vibrational wavenumbers, infrared intensities and Raman activities were calculated using DFT (B3LYP and LSDA) methods using 6-311++G (d,p) basis set. The most stable conformer of TBMP was identified from the computational results. The assignments of vibrational spectra have been carried out with the help of normal co-ordinate analysis (NCA) following the scaled quantum mechanical force field (SQMFF) methodology. The first order hyperpolarizability (?0) and related properties (?, ?0 and ??) of TBMP have been discussed. The stability and charge delocalization of the molecule was studied by Natural Bond Orbital (NBO) analysis. UV-Visible spectrum and effects of solvents have been discussed and the electronic properties such as HOMO and LUMO energies were determined by time-dependent TD-DFT approach with B3LYP/6-311++G (d,p) level of theory. The molecule orbital contributions are studied by density of energy states (DOSs). The reactivity sites are identified by mapping the electron density into electrostatic potential surface (MEP). Mulliken analysis of atomic charges is also calculated. The thermodynamic properties at different temperatures were calculated, revealing the correlations between standard heat capacities, standard entropy and standard enthalpy changes with temperatures. Global hardness, global softness, global electrophilicity and ionization potential of the title compound are determined.

Saravanan, S.; Balachandran, V.

2014-09-01

410

Spectroscopic data and Stark broadening of Cu I and Ag I spectral lines: Selection and analysis  

NASA Astrophysics Data System (ADS)

Optical emission and linear laser absorption spectroscopy techniques were used in investigation of plasma with copper and silver admixture. The method of selection of spectral lines and spectroscopic data with the aim of diagnostics of multicomponent air plasma with two metal vapors admixture was developed. Energy level populations behavior on the Boltzmann plot were used for Cu I and Ag I spectroscopic data selection. In this way the selection of spectroscopic data for some of Cu I and Ag I lines was realized. Stark broadening parameters of Cu I and Ag I were examined. Experimentally obtained temperature and electron density radial distributions were used in the calculation of plasma composition in the assumption of local thermodynamic equilibrium. Linear laser absorption spectroscopy was used to examine the state of plasma.

Babich, I. L.; Boretskij, V. F.; Veklich, A. N.; Semenyshyn, R. V.

2014-10-01

411

Spectroscopic Imaging of Bladder Cancer  

SciTech Connect

The feasibility of developing bladder cancer detection methods using intrinsic tissue optical properties is the focus of this investigation. In vitro experiments have been performed using polarized elastic light scattering in combination with tissue autofluorescence in the NIR spectral region under laser excitation in the green and red spectral regions. The experimental results obtained from a set of tissue specimens from 25 patients reveal the presence of optical fingerprint characteristics suitable for cancer detection with high contrast and accuracy. These photonic methods are compatible with existing endoscopic imaging modalities which make them suitable for in-vivo application.

Demos, S G; Gandour-Edwards, R; Ramsamooj, R; deVere White, R

2003-01-01

412

Nondestructive and Rapid Concurrent Estimation of Paracetamol and Nimesulide in Their Combined Dosage Form Using Raman Spectroscopic Technique  

PubMed Central

A rapid, nondestructive Raman spectroscopic method was developed for quantitative estimation of paracetamol and nimesulide in their combined dosage form. A Raman univariate calibration model was developed by measuring the peak intensities of paracetamol and nimesulide at 853 cm?1 and 1336 cm?1, respectively. The developed method was successfully applied for in situ, concurrent estimation of paracetamol and nimesulide in their combined dosage and method was also validated according to International Conference on Harmonisation guidelines. Thus, the developed Raman spectroscopic method can be applied for simultaneous estimation of paracetamol and nimesulide in their combined dosage form as a process analytical technology tool by pharmaceutical industries for routine quality control. PMID:24019571

Lakhwani, Gargi R.; Sherikar, O. D.; Mehta, Priti J.

2013-01-01

413

Selecting asteroids for a targeted spectroscopic survey  

NASA Astrophysics Data System (ADS)

Context. Asteroid spectroscopy reflects surface mineralogy. There are a few thousand asteroids whose surfaces have been observed spectrally. Determining their surface properties is important for many practical and scientific applications, such as developing impact deflection strategies or studying the history and evolution of the solar system and planet formation. Aims: The aim of this study is to develop a preselection method that can be used to search for asteroids of any taxonomic complex. The method could then be utilized in multiple applications, such as searching for the missing V-types or looking for primitive asteroids. Methods: We used the Bayes Naive Classifier combined with observations obtained in the course of the Sloan Digital Sky Survey and the Wide-field Infrared Survey Explorer surveys, as well as a database of asteroid phase curves for asteroids with a known taxonomic type. With this new classification method, we selected a number of possible V-type candidates. Some of the candidates were then spectrally observed at the Nordic Optical Telescope and South African Large Telescope. Results: We developed and tested the new preselection method. We found three asteroids in the mid-to-outer main belt that probably have differentiated types. Near-infrared observations are still required to confirm this discovery. As in other studies we found that V-type candidates cluster around the Vesta family and are rare in the mid-to-outer main belt. Conclusions: The new method shows that even largely explored large databases when combined could still be exploited further in, for example, solving the missing dunite problem. Tables 6 and A.1 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/572/A29

Oszkiewicz, D. A.; Kwiatkowski, T.; Tomov, T.; Birlan, M.; Geier, S.; Penttilä, A.; Poli?ska, M.

2014-12-01

414

Spectroscopic Bounds on New Physics  

E-print Network

We use atomic spectra to extend pure Coulomb's law tests to larger masses. We interpret these results in terms of constraints for hidden sector photons. With existing data the bounds for hidden photons are not improved. However we find that our atomic spectra bounds are an especially clean and model-independent complement to existing ones from other methods. We also show that data from future tests of true muonium and muonic atoms could produce atomic spectra bounds which probe untested parameter space.

Joerg Jaeckel; Sabyasachi Roy

2010-11-02

415

Spectroscopic determinations of solar rotation  

Microsoft Academic Search

Spectral line shift data obtained from full-disk magnetograms recorded at Mt. Wilson are analyzed for differential rotation. The method of analysis is discussed and the results from the data for 1966 through 1968 are presented. The average equatorial velocity over this period is found to be 1.93 km\\/sec or 13.76 deg\\/day (sidereal). This corresponds to a sidereal period of 26.16

Robert Howard; J. Harvey

1970-01-01

416

Evaluation of Salt Influence on Sugar Consumption by Suspension Cells Based on Spectroscopic Analysis  

PubMed Central

The influence of metal salt on sugar consumption by suspension cells in food models constructed by a sugar and salt aqueous solution was investigated based on mid-infrared spectroscopic analysis. The contaminated suspension cells in the food model could be detected using the spectral feature change that measured the present spectrum subtracted in the initial spectrum. The cells were prepared for growth and although the cell did not grow under the induction period, the cell activation (start of sugar metabolism) was detected on the subtracted spectral behavior before the cell growth. The rough grasp of the spectral change behavior is useful for the high-throughput spectroscopic method to detect the contaminated cell activation. Furthermore, the detailed sugar consumption kinetics of the cells was also investigated based on the spectroscopic method. The kind of added salt in the food model influenced the cell activation and the potassium ions play an important role in the plant cells. The living cells activity in fresh food may act to prevent microbial contamination and to suppress the growth of the contaminated microorganism. Both the simple and detailed analyses based on the spectroscopic method presented in this study might be useful for risk management of food. PMID:24490105

Kameoka, Takaharu; Hashimoto, Atsushi

2013-01-01

417

Investigation on interaction of prulifloxacin with pepsin: A spectroscopic analysis  

NASA Astrophysics Data System (ADS)

The interaction between prulifloxacin, a kind of new oral taking antibiotic and pepsin, a kind of enzyme in the stomach has been investigated in vitro under a simulated physiological condition by different spectroscopic methods. The intrinsic fluorescence of pepsin was strongly quenched by prulifloxacin. This effect was rationalized in terms of a static quenching procedure. The binding parameters have been evaluated by fluorescence quenching methods. The negative value of ? G0 reveals that the binding process is a spontaneous process. The binding distance R between donor (pepsin) and acceptor (prulifloxacin) was obtained according to the Förster's resonance energy transfer theory and found to be 0.95 nm. The results obtained herein will be of biological significance in pharmacology and clinical medicine.

Huang, Yabei; Yan, Jie; Liu, Benzhi; Yu, Zhang; Gao, Xiaoyan; Tang, Yingcai; Zi, Yanqin

2010-03-01

418

Three-dimensional spherical analyses of cosmological spectroscopic surveys  

NASA Astrophysics Data System (ADS)

Spectroscopic redshift surveys offer great prospects for constraining the dark sector in cosmology. Future surveys will however be both deep and wide and will thus require an analysis in three-dimensional spherical geometry. We review and compare several methods which have been proposed in the literature for this purpose, focusing in particular on implementations of the spherical harmonic tomography (SHT) power spectrum Clij and the spherical Fourier Bessel (SFB) power spectrum Cl(k ,k'). Using a Fisher analysis, we compare the forecasted constraints on cosmological parameters using these statistics. These constraints typically rely on approximations such as the Limber approximation and make specific choices in the numerical implementation of each statistic. Using a series of toy models, we explore the applicability of these approximations and study the sensitivity of the SHT and SFB statistics to the details of their implementation. In particular, we show that overlapping redshift bins may improve cosmological constraints using the SHT statistic when the number of bins is small, and that the SFB constraints are quite robust to changes in the assumed distance-redshift relation. We also find that the SHT can be tailored to be more sensitive to modes at redshifts close to the survey boundary, while the SFB appears better suited to capture information beyond the smooth shape of the power spectrum. In this context, we discuss the pros and cons of the different techniques and their impact on the design and analysis of future wide field spectroscopic surveys.

Nicola, Andrina; Refregier, Alexandre; Amara, Adam; Paranjape, Aseem

2014-09-01

419

DFT computations and spectroscopic analysis of p-bromoacetanilide  

NASA Astrophysics Data System (ADS)

This work presents the characterization of p-bromoacetanilide (PBA) by quantum chemical calculations and spectral techniques. The spectroscopic properties were investigated by FT-IR, FT-Raman and UV-Vis techniques. The structural and spectroscopic data of the molecule were obtained from B3LYP/6-311++ G(d,p) and MPW1PW91/6-311++G(d,p) basis set calculations. The theoretical wavenumbers were scaled and compared with experimental FT-IR and FT-Raman spectra. The complete assignments were performed on the basis of the normal co-ordinate analysis (NCA), experimental results and potential energy distribution (PED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method, interpreted in terms of fundamental modes. The stability of molecule has been analyzed by NBO/NLMO analysis. The molecular orbital contributions were studied by using the density of states. The electronic properties like UV-Vis spectral analysis and HOMO-LUMO energies were reported. The calculated HOMO and LUMO energies shows that charge transfer interactions taking place within the molecule. Mulliken population analysis on atomic charges, Statistical thermodynamic properties at various temperatures of the PBA is also calculated.

Gnanasambandan, T.; Gunasekaran, S.; Seshadri, S.

2014-03-01

420

DFT computations and spectroscopic analysis of p-bromoacetanilide.  

PubMed

This work presents the characterization of p-bromoacetanilide (PBA) by quantum chemical calculations and spectral techniques. The spectroscopic properties were investigated by FT-IR, FT-Raman and UV-Vis techniques. The structural and spectroscopic data of the molecule were obtained from B3LYP/6-311++ G(d,p) and MPW1PW91/6-311++G(d,p) basis set calculations. The theoretical wavenumbers were scaled and compared with experimental FT-IR and FT-Raman spectra. The complete assignments were performed on the basis of the normal co-ordinate analysis (NCA), experimental results and potential energy distribution (PED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method, interpreted in terms of fundamental modes. The stability of molecule has been analyzed by NBO/NLMO analysis. The molecular orbital contributions were studied by using the density of states. The electronic properties like UV-Vis spectral analysis and HOMO-LUMO energies were reported. The calculated HOMO and LUMO energies shows that charge transfer interactions taking place within the molecule. Mulliken population analysis on atomic charges, Statistical thermodynamic properties at various temperatures of the PBA is also calculated. PMID:24334018

Gnanasambandan, T; Gunasekaran, S; Seshadri, S

2014-03-25

421

Novel dipodal Schiff base compounds: Synthesis, characterization and spectroscopic studies  

NASA Astrophysics Data System (ADS)

Two novel dipodal Schiff base compounds 1,2-benzyloxy-bis-[2-(benzylideneamino)phenol, L1 and 1,2-benzyloxy-bis[3-(benzylideneamino)pyridine], L2 were synthesized. Their sensing actions were confirmed by UV-Vis absorbance and emission spectroscopic studies in presence of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Sn(II), Cd(II) and Pb(II) in methanol medium (1 × 10-4 M). It was found that the dipodal compounds can selectively bind to Cu(II) and Pb(II) metal ions with a significant change in its emission and absorption spectra, while the addition of other metal ions (Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Sn(II), Cd(II) and Pb(II)) produces insignificant or minor changes. The host-guest complexes formed were determined by Job's plot method. As a chemosensor, L1 and L2 dipodal Schiff base compounds shows a specific selectivity towards Cu(II) and Pb(II) ions in according to all spectroscopic data.

Obali, Aslihan Yilmaz; Ucan, Halil Ismet

2015-02-01

422

Quantitative spectroscopic studies of a pulsed plasma microthruster  

NASA Astrophysics Data System (ADS)

The absolute intensity of the emission spectra emitted from a PPT plume was studied from both experimental measurements and theoretical analysis to investigate its interference with an optical sensor/signal. The results were also used to estimate the absolute radiant-energy emitted from the PPT plume to compare with the input energy for the energy-budget analysis. Initially the radiating species in the PPT plume were identified by the spectroscopic measurements. For the identified species, the absolute intensity was obtained in three methods. In the first method, the intensity was experimentally measured with the quantitative spectroscopic apparatus to provide the experimental intensity. In the second method, the intensity was theoretically calculated with the experimental results assuming the observed plasma to be spatially uniform and temporally constant for simplification to provide the spatially and temporally uniform (STU) semi-empirical theoretical intensity. In the third method, the intensity was theoretically calculated independently from the experimental results using the MACH2 magnetohydrodynamic code to provide the spatially and temporally nonuniform (STN) fully theoretical intensity. The STU theoretical intensity has reasonable agreement with the experimental intensity to capture the trend although the STU values are larger by up to four times. This discrepancy was reduced by STN theoretical intensity which predicted well the experimental value. Using the result of the experimental intensity and the STN theoretical intensity, the radiant energy was estimated. The experimental and the theoretical radiant energies increase with the input energy in an approximately linear fashion. The result indicates that the radiative loss due to the spontaneous line emission in the range of 400 to 700 nm is at most 0.02% of the input energy. The comparisons of absolute intensity measurements and calculations of radiant energy based on MACH2 MHD simulations indicate that such simulations can provide adequate guides for estimating the amount of radiation from PPTs.

Umeki, Tomokazu

2001-06-01

423

Active learning in the presence of unlabelable examples  

NASA Technical Reports Server (NTRS)

We propose a new active learning framework where the expert labeler is allowed to decline to label any example. This may be necessary because the true label is unknown or because the example belongs to a class that is not part of the real training problem. We show that within this framework, popular active learning algorithms (such as Simple) may perform worse than random selection because they make so many queries to the unlabelable class. We present a method by which any active learning algorithm can be modified to avoid unlabelable examples by training a second classifier to distinguish between the labelable and unlabelable classes. We also demonstrate the effectiveness of the method on two benchmark data sets and a real-world problem.

Mazzoni, Dominic; Wagstaff, Kiri

2004-01-01

424

Methods  

USGS Publications Warehouse

Detecting declines in population size is one of the highest priorities of the shorebird initiatives in Canada and the United States. The quantitative goal is 80% power to detect a 50% decline, occurring during no more than 20 years, with a significance level of 0.15, using a two-tailed test, and incorporating effects of potential bias into the estimator. The Arctic PRISM program was designed to achieve this goal for arctic-nesting shorebird populations. The survey methods are an application of double sampling. Rapid surveys were made on a large number of plots selected from throughout arctic Alaska and Canada using stratified random sampling. Intensive surveys were made on a subsample of the plots to obtain detection rates, which were used to calibrate results from rapidly surveyed plots. Surveys will be made of the entire arctic region, each lasting several years and producing an estimate of average population size during the survey period. Results from two or more survey periods will be used to estimate change, or trend, in population size.

Bart, Jonathan; Johnston, Victoria; Smith, Paul A.; Manning, Ann; Rausch, Jennie; Brown, Stephen

2012-01-01

425

A Pictorial Query-by-Example Language  

Microsoft Academic Search

this paper we describe a Pictorial Query-By-Example (PQBE)language aimed at the retrieval of direction relations from symbolic images. As in thecase of verbal Query-By-Example, PQBE generalises from the example given by theuser, but instead of having queries in the form of skeleton tables showing the relationscheme, we have skeleton images which are themselves symbolic images. PQBEprovides an intuitive interface for

Dimitris Papadias; Timos K. Sellis

1995-01-01

426

Implementation of a Spectroscopic Method for Determining Ion Temperature  

NASA Astrophysics Data System (ADS)

The Redmond Plasma Physics Laboratory is using its TCS device to investigate Rotating Magnetic Field current drive for Field Reversed Configuration plasmas. This poster will discuss the determination of the average ion temperature of plasma in TCS for various conditions through measurement of Doppler broadening of the D_? line and associated spectrum. Data is collected by two systems, a 0.5 m spectrometer using a 1024 × 256 CCD, and a 16-anode photomultiplier tube. A 147 l/mm grating and a 2400 l/mm grating are used with the spectrometer to view relatively broad regions of the emission spectrum, while the photomultiplier tube concentrates on specific segments. Work supported by US Department of Energy. http://www.aa.washington.edu/AERP/RPPL

Fredrickson, Carl; Crawford, Edward; Miller, Ken; Slough, John; Cohen, Sam

1999-11-01

427

SPECTROSCOPIC METHODS FOR DETERMINING THE OXIDATION OF BIODIESEL FUEL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mono-alkyl esters (usually methyl esters) of vegetable oils and animal fats are achieving increasing significance as alternative diesel fuel, in which case they are called biodiesel. As the fatty acid chains of the original vegetable oil or animal fat are retained in biodiesel, the reactions these ...

428

The HITRAN 2008 Molecular Spectroscopic Database  

NASA Technical Reports Server (NTRS)

This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e., spectra in which the individual lines are not resolved; individual line parameters and absorption cross sections for bands in the ultra-violet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for forty-two molecules including many of their isotopologues.

Rothman, Laurence S.; Gordon, Iouli E.; Barbe, Alain; Benner, D. Chris; Bernath, Peter F.; Birk, Manfred; Boudon, V.; Brown, Linda R.; Campargue, Alain; Champion, J.-P.; Chance, Kelly V.; Coudert, L. H.; Sung, K.; Toth, R. A.

2009-01-01

429

Contrast agents and spectroscopic probes in NMR.  

PubMed

The demand for higher diagnostic specificity has led to the increased use of "foreign" agents to increase tissue contrast and/or spectroscopic sensitivity in NMR studies. The primary agents used to enhance tissue contrast in NMR imaging are paramagnetic. They cause a decrease in the proton T1 of H2O leading to enhanced signal intensity. This effect depends on the large gyromagnetic ratio of the electron, the number of unpaired electrons, the concentration of paramagnetic ions, the number of coordinated water molecules, and the rate of exchange of water. Spectroscopic enhancement has relied primarily on attempt at isotopic enrichment (usually C-13), which causes a direct increase in signal. PMID:6544819

Koutcher, J A; Burt, C T; Lauffer, R B; Brady, T J

1984-04-01

430

The Lyman far ultraviolet spectroscopic explorer mission  

NASA Technical Reports Server (NTRS)

The Lyman-FUSE (Far Ultraviolet Spectroscopic Explorer) mission selected in 1989 for definition and development for flight is described. FUSE will obtain spectra in the 912 to 1250 angstrom region with unprecedented sensitivity. This spectral interval is extraordinarily rich in strong atomic and molecular transitions, including the Lyman series of hydrogen and deuterium, molecular hydrogen (H2 and HD) and the strong transitions of important ions such as N I to III, C I to IV, P II to V, O VI and S III to VI. FUSE will bridge the spectral gap between Hubble Space Telescope and the x ray regime with an additional moderate resolution spectroscopic capability covering 100 to 912 angstroms.

Sonneborn, George

1990-01-01

431

PESSTO spectroscopic classification of optical transients  

NASA Astrophysics Data System (ADS)

PESSTO, the Public ESO Spectroscopic Survey for Transient Objects (see Valenti et al., ATel #4037; http://www.pessto.org ), reports the following supernova classifications. Targets were supplied by the La Silla-Quest survey (see Hadjiyska et al., ATel #3812). All observations were performed on the ESO New Technology Telescope at La Silla on 2012 December 13, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution).

Pan, Y.; Guillou, L. Le; Baumont, S.; Sullivan, M.; Taubenberger, S.; Valenti, S.; Pastorello, A.; Benetti, S.; Smartt, S. J.; Smith, K.; Young, D.; Gal-Yam, A.; Yaron, O.; Baltay, C.; Ellman, N.; Hadjiyska, E.; McKinnon, R.; Rabinowitz, D.; Walker, E. S.; Feindt, U.; Kowalski, M.; Nugent, P.

2012-12-01

432

PESSTO spectroscopic classification of optical transients  

NASA Astrophysics Data System (ADS)

PESSTO, the Public ESO Spectroscopic Survey for Transient The Objects (see Valenti et al., ATel #4037; http://www.pessto.org ), reports the following supernova classification. The target was supplied by the La Silla-Quest survey (see Hadjiyska et al., ATel #3812). The observation was performed on the ESO New Technology Telescope at La Silla on 2012 December 06, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution).

Le Guillou, L.; Baumont, S.; Maguire, K.; Pan, Y.; Sullivan, M.; Taubenberger, S.; Valenti, S.; Pastorello, A.; Benetti, S.; Smartt, S. J.; Smith, K.; Young, D.; Gal-Yam, A.; Yaron, O.; Baltay, C.; Ellman, N.; Hadjiyska, E.; McKinnon, R.; Rabinowitz, D.; Walker, E. S.; Feindt, U.; Kowalski, M.; Nugent, P.

2012-12-01

433

PESSTO spectroscopic classification of optical transients  

NASA Astrophysics Data System (ADS)

PESSTO, the Public ESO Spectroscopic Survey for Transient Objects (see Valenti et al., ATel #4037; http://www.pessto.org ), reports the following supernova classification. The target was supplied by the Catalina Real-time Transient Survey (http://crts.caltech.edu/). The observation was performed on the ESO New Technology Telescope at La Silla on 2012 December 20, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution).

Le Guillou, L.; Baumont, S.; Maguire, K.; Sullivan, M.; Taubenberger, S.; Valenti, S.; Pastorello, A.; Benetti, S.; Smartt, S. J.; Smith, K.; Young, D.; Gal-Yam, A.; Yaron, O.

2012-12-01

434

PESSTO spectroscopic classification of optical transients  

NASA Astrophysics Data System (ADS)

PESSTO, the Public ESO Spectroscopic Survey for Transient The Objects (see Valenti et al., ATel #4037; http://www.pessto.org ), reports the following supernova classifications. Targets were supplied by the La Silla-Quest survey (see Hadjiyska et al., ATel #3812). All observations were performed on the ESO New Technology Telescope at La Silla on 2012 December 12, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution).

Guillou, L. Le; Baumont, S.; Pan, Y.; Sullivan, M.; Taubenberger, S.; Valenti, S.; Pastorello, A.; Benetti, S.; Smartt, S. J.; Smith, K.; Young, D.; Gal-Yam, A.; Yaron, O.; Baltay, C.; Ellman, N.; Hadjiyska, E.; McKinnon, R.; Rabinowitz, D.; Walker, E. S.; Feindt, U.; Kowalski, M.; Nugent, P.

2012-12-01

435

Soil Organic Phosphorus Speciation Using Spectroscopic Techniques  

Microsoft Academic Search

\\u000a The most commonly used differentiation of soil phosphorus (P) is between inorganic and organic forms, despite the fact that\\u000a this is only the beginning of soil P speciation. Forms of inorganic and organic soil P include a large range of specific P\\u000a compounds, and spectroscopic techniques can offer the best potential for determining the speciation of soil organic P. The

Ashlea L. Doolette; Ronald J. Smernik

436

Spectroscopic Classification of ASASSN-14mf  

NASA Astrophysics Data System (ADS)

We report optical spectroscopic observations of ASASSN-14mf (ATel #6831) obtained on UT Nov 22.1 with FAST (range 3600-7450 Angstroms) mounted on the F. L. Whipple Observatory 1.5-m telescope. The spectrum shows features characteristic of a normal Type Ia SN around maximum light. After correcting for the redshift of the host galaxy, we measure a Si II 6355 velocity of -10200 km/s.

Falco, E.; Berlind, P.; Calkins, M.; Prieto, J. L.; Stanek, K. Z.; Challis, P.; Kirshner, R. P.

2014-12-01

437

Pessto spectroscopic classification of optical transients  

NASA Astrophysics Data System (ADS)

PESSTO, the Public ESO Spectroscopic Survey for Transient Objects (see Valenti et al., ATel #4037; http://www.pessto.org ), reports the following supernova classifications. Targets were supplied by the Catalina Real-time Transient Survey (http://crts.caltech.edu/) and OGLE-IV (ATel #4495; Wyrzykowski et al. 2012). All observations were performed on the ESO New Technology Telescope at La Silla on 2013 Dec 23, using EFOSC2 and Grism 13 (3985-9315A, 18A resolution).

Le Guillou, L.; Fleury, M.; Leget, P.-F.; Balland, C.; Baumont, S.; Pastorello, A.; Benetti, S.; Inserra, C.; Smartt, S.; Smith, K.; Young, D.; Sullivan, M.; Taubenberger, S.; Valenti, S.; Fraser, M.; Yaron, O.; Manulis, I.; Gal-Yam, A.; Knapic, C.; Smareglia, R.; Molinaro, M.; Wyrzykowski, L.

2013-12-01