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Sample records for mass spectral library

  1. Mass Spectral Library Quality Assurance by Inter-Library Comparison

    Science.gov (United States)

    Wallace, William E.; Ji, Weihua; Tchekhovskoi, Dmitrii V.; Phinney, Karen W.; Stein, Stephen E.

    2017-01-01

    A method to discover and correct errors in mass spectral libraries is described. Comparing across a set of highly curated reference libraries compounds that have the same chemical structure quickly identifies entries that are outliers. In cases where three or more entries for the same compound are compared, the outlier as determined by visual inspection was almost always found to contain the error. These errors were either in the spectrum itself or in the chemical descriptors that accompanied it. The method is demonstrated on finding errors in compounds of forensic interest in the NIST/EPA/NIH Mass Spectral Library. The target list of compounds checked was the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG) mass spectral library. Some examples of errors found are described. A checklist of errors that curators should look for when performing inter-library comparisons is provided.

  2. Spectral library searching in proteomics.

    Science.gov (United States)

    Griss, Johannes

    2016-03-01

    Spectral library searching has become a mature method to identify tandem mass spectra in proteomics data analysis. This review provides a comprehensive overview of available spectral library search engines and highlights their distinct features. Additionally, resources providing spectral libraries are summarized and tools presented that extend experimental spectral libraries by simulating spectra. Finally, spectrum clustering algorithms are discussed that utilize the same spectrum-to-spectrum matching algorithms as spectral library search engines and allow novel methods to analyse proteomics data.

  3. Advances in the use of mass spectral libraries for forensic toxicology.

    Science.gov (United States)

    Aebi, Beat; Bernhard, Werner

    2002-04-01

    Gas chromatography in combination with mass spectrometry (GC-MS) plays an important role in the field of analytical toxicology. The identification of unknown compounds is very frequently undertaken with GC-MS and utilizing mass spectral libraries. Currently available libraries for analytical toxicology were compared for overlapping and uniqueness of their entries. Furthermore, the widely known Pfleger-Maurer-Weber-Drugs-and-Pesticides-Library for toxicology (PMW_tox2) was used to compare the search algorithms PBM (Probability Based Matching, Agilent Technologies), INCOS (Finnigan/Thermoquest), and MassLib (Max Planck Institute). To our knowledge, direct comparisons of mass spectral libraries and search programs for analytical toxicology have not been published previously. The capabilities and necessities of modern MS technology in the field of general unknown analysis are revealed, and some of the potential pitfalls are described.

  4. Mass spectral reference libraries: an ever-expanding resource for chemical identification.

    Science.gov (United States)

    Stein, Stephen

    2012-09-04

    The basic principles, practices, and pitfalls in the process of compound identification by searching mass spectral reference libraries are presented. Factors affecting the identification process are discussed as members of one of three major contributors to identification confidence: prior probability, risk of false negative results, and risk of false positive results. More general concerns and the problem of "unknown unknowns" are then explored.

  5. Fast parallel tandem mass spectral library searching using GPU hardware acceleration.

    Science.gov (United States)

    Baumgardner, Lydia Ashleigh; Shanmugam, Avinash Kumar; Lam, Henry; Eng, Jimmy K; Martin, Daniel B

    2011-06-03

    Mass spectrometry-based proteomics is a maturing discipline of biologic research that is experiencing substantial growth. Instrumentation has steadily improved over time with the advent of faster and more sensitive instruments collecting ever larger data files. Consequently, the computational process of matching a peptide fragmentation pattern to its sequence, traditionally accomplished by sequence database searching and more recently also by spectral library searching, has become a bottleneck in many mass spectrometry experiments. In both of these methods, the main rate-limiting step is the comparison of an acquired spectrum with all potential matches from a spectral library or sequence database. This is a highly parallelizable process because the core computational element can be represented as a simple but arithmetically intense multiplication of two vectors. In this paper, we present a proof of concept project taking advantage of the massively parallel computing available on graphics processing units (GPUs) to distribute and accelerate the process of spectral assignment using spectral library searching. This program, which we have named FastPaSS (for Fast Parallelized Spectral Searching), is implemented in CUDA (Compute Unified Device Architecture) from NVIDIA, which allows direct access to the processors in an NVIDIA GPU. Our efforts demonstrate the feasibility of GPU computing for spectral assignment, through implementation of the validated spectral searching algorithm SpectraST in the CUDA environment.

  6. Denoising peptide tandem mass spectra for spectral libraries: a Bayesian approach.

    Science.gov (United States)

    Shao, Wenguang; Lam, Henry

    2013-07-05

    With the rapid accumulation of data from shotgun proteomics experiments, it has become feasible to build comprehensive and high-quality spectral libraries of tandem mass spectra of peptides. A spectral library condenses experimental data into a retrievable format and can be used to aid peptide identification by spectral library searching. A key step in spectral library building is spectrum denoising, which is best accomplished by merging multiple replicates of the same peptide ion into a consensus spectrum. However, this approach cannot be applied to "singleton spectra," for which only one observed spectrum is available for the peptide ion. We developed a method, based on a Bayesian classifier, for denoising peptide tandem mass spectra. The classifier accounts for relationships between peaks, and can be trained on the fly from consensus spectra and immediately applied to denoise singleton spectra, without hard-coded knowledge about peptide fragmentation. A linear regression model was also trained to predict the number of useful "signal" peaks in a spectrum, thereby obviating the need for arbitrary thresholds for peak filtering. This Bayesian approach accumulates weak evidence systematically to boost the discrimination power between signal and noise peaks, and produces readily interpretable conditional probabilities that offer valuable insights into peptide fragmentation behaviors. By cross validation, spectra denoised by this method were shown to retain more signal peaks, and have higher spectral similarities to replicates, than those filtered by intensity only.

  7. Mass Spectral Library, NIST '02 With Windows 2.0 Software

    Science.gov (United States)

    SRD 1A NIST/EPA/NIH Mass Spectral Library, NIST '02 With Windows 2.0 Software (PC database for purchase)   Available with full-featured NIST MS Search Program for Windows integrated tools, the NIST '98 is a fully evaluated collection of electron-ionization mass spectra. (147,198 Compounds with Spectra; 147,194 Chemical Structures; 174,948 Spectra )

  8. Construction of an Ultrahigh Pressure Liquid Chromatography-Tandem Mass Spectral Library of Plant Natural Products and Comparative Spectral Analyses.

    Science.gov (United States)

    Lei, Zhentian; Jing, Li; Qiu, Feng; Zhang, Hua; Huhman, David; Zhou, Zhiqin; Sumner, Lloyd W

    2015-07-21

    A plant natural product tandem mass spectral library has been constructed using authentic standards and purified compounds. Currently, the library contains 1734 tandem mass spectra for 289 compounds, with the majority (76%) of the compounds being plant phenolics such as flavonoids, isoflavonoids, and phenylpropanoids. Tandem mass spectra and chromatographic retention data were acquired on a triple quadrupole mass spectrometer coupled to an ultrahigh pressure liquid chromatograph using six different collision energies (CEs) (10-60 eV). Comparative analyses of the tandem mass spectral data revealed that the loss of ring substituents preceded the C-ring opening during the fragmentation of flavonoids and isoflavonoids. At lower CE (i.e., 10 and 20 eV), the flavonoids and isoflavonoid central ring structures typically remained intact, and fragmentation was characterized by the loss of the substituents (i.e., methyl and glycosyl groups). At higher CE, the flavonoid and isoflavonoid core ring systems underwent C-ring cleavage and/or rearrangement depending on the structure, particularly hydroxylation patterns. In-source electrochemical oxidation was observed for phenolics that had ortho-diphenol moieties (i.e., vicinal hydroxyl groups on the aromatic rings). The ortho-diphenols were oxidized to ortho-quinones, yielding an intensive and, in most cases, a base ion peak corresponding to a [(M - 2H) - H](-) ion in their mass spectra. The library also contains reverse-phase retention times, allowing for the construction, validation, and testing of an artificial neural network retention prediction of other flavonoids and isoflavonoids not contained within the library. The library is freely available for nonprofit, academic use and it can be downloaded at http://www.noble.org/apps/Scientific/WebDownloadManager/DownloadArea.aspx.

  9. Towards a universal product ion mass spectral library - reproducibility of product ion spectra across eleven different mass spectrometers.

    Science.gov (United States)

    Hopley, Chris; Bristow, Tony; Lubben, Anneke; Simpson, Alec; Bull, Elaine; Klagkou, Katerina; Herniman, Julie; Langley, John

    2008-06-01

    Product ion spectra produced by collision-induced dissociation (CID) in tandem mass spectrometry experiments can differ markedly between instruments. There have been a number of attempts to standardise the production of product ion spectra; however, a consensus on the most appropriate approach to the reproducible production of spectra has yet to be reached. We have previously reported the comparison of product ion spectra on a number of different types of instruments - a triple quadrupole, two ion traps and a Fourier transform ion cyclotron resonance mass spectrometer (Bristow AWT, Webb KS, Lubben AT, Halket JM. Rapid Commun. Mass Spectrom. 2004; 18: 1). The study showed that a high degree of reproducibility was achievable. The goal of this study was to improve the comparability and reproducibility of CID product ion mass spectra produced in different laboratories and using different instruments. This was carried out experimentally by defining a spectral calibration point on each mass spectrometer for product ion formation. The long-term goal is the development of a universal (instrument independent) product ion mass spectral library for the identification of unknowns. The spectra of 48 compounds have been recorded on eleven mass spectrometers: six ion traps, two triple quadrupoles, a hybrid triple quadrupole, and two quadrupole time-of-flight instruments. Initially, 4371 spectral comparisons were carried out using the data from eleven instruments and the degree of reproducibility was evaluated. A blind trial has also been carried out to assess the reproducibility of spectra obtained during LC/MS/MS. The results suggest a degree of reproducibility across all instrument types using the tuning point technique. The reproducibility of the product ion spectra is increased when comparing the tandem in time type instruments and the tandem in space instruments as two separate groups. This may allow the production of a more limited, yet useful, screening library for LC

  10. Development of a dedicated peptide tandem mass spectral library for conservation science.

    Science.gov (United States)

    Fremout, Wim; Dhaenens, Maarten; Saverwyns, Steven; Sanyova, Jana; Vandenabeele, Peter; Deforce, Dieter; Moens, Luc

    2012-05-30

    In recent years, the use of liquid chromatography tandem mass spectrometry (LC-MS/MS) on tryptic digests of cultural heritage objects has attracted much attention. It allows for unambiguous identification of peptides and proteins, and even in complex mixtures species-specific identification becomes feasible with minimal sample consumption. Determination of the peptides is commonly based on theoretical cleavage of known protein sequences and on comparison of the expected peptide fragments with those found in the MS/MS spectra. In this approach, complex computer programs, such as Mascot, perform well identifying known proteins, but fail when protein sequences are unknown or incomplete. Often, when trying to distinguish evolutionarily well preserved collagens of different species, Mascot lacks the required specificity. Complementary and often more accurate information on the proteins can be obtained using a reference library of MS/MS spectra of species-specific peptides. Therefore, a library dedicated to various sources of proteins in works of art was set up, with an initial focus on collagen rich materials. This paper discusses the construction and the advantages of this spectral library for conservation science, and its application on a number of samples from historical works of art.

  11. Large Spectral Library Problem

    Energy Technology Data Exchange (ETDEWEB)

    Chilton, Lawrence K.; Walsh, Stephen J.

    2008-10-03

    Hyperspectral imaging produces a spectrum or vector at each image pixel. These spectra can be used to identify materials present in the image. In some cases, spectral libraries representing atmospheric chemicals or ground materials are available. The challenge is to determine if any of the library chemicals or materials exist in the hyperspectral image. The number of spectra in these libraries can be very large, far exceeding the number of spectral channels collected in the ¯eld. Suppose an image pixel contains a mixture of p spectra from the library. Is it possible to uniquely identify these p spectra? We address this question in this paper and refer to it as the Large Spectral Library (LSL) problem. We show how to determine if unique identi¯cation is possible for any given library. We also show that if p is small compared to the number of spectral channels, it is very likely that unique identi¯cation is possible. We show that unique identi¯cation becomes less likely as p increases.

  12. Evaluation of the sensitivity of the 'Wiley registry of tandem mass spectral data, MSforID' with MS/MS data of the 'NIST/NIH/EPA mass spectral library'.

    Science.gov (United States)

    Oberacher, Herbert; Whitley, Graeme; Berger, Bernd

    2013-04-01

    Tandem mass spectral libraries are versatile tools for small molecular identification finding application in forensic science, doping control, drug monitoring, food and environmental analysis, as well as metabolomics. Two important libraries are the 'Wiley Registry of Tandem Mass Spectral Data, MSforID' (Wiley Registry MSMS) and the collection of MS/MS spectra part of the 2011 edition of the 'NIST/NIH/EPA Mass Spectral Library' (NIST 11 MSMS). Herein, the sensitivity and robustness of the Wiley Registry MSMS were evaluated using spectra extracted from the NIST 11 MSMS library. The sample set was found to be heterogeneous in terms of mass spectral resolution, type of CID, as well as applied collision energies. Nevertheless, sensitive compound identification with a true positive identification rate ≥95% was possible using either the MSforID Search program or the NIST MS Search program 2.0g for matching. To rate the performance of the Wiley Registry MSMS, cross-validation experiments were repeated using subcollections of NIST 11 MSMS as reference library and spectra extracted from the Wiley Registry MSMS as positive controls. Unexpectedly, with both search algorithms tested, correct results were obtained in less than 88% of cases. We examined possible causes for the results of the cross validation study. The large number of precursor ions represented by a single tandem mass spectrum only was identified as the basic cause for the comparably lower sensitivity of the NIST library.

  13. [Review of digital ground object spectral library].

    Science.gov (United States)

    Zhou, Xiao-Hu; Zhou, Ding-Wu

    2009-06-01

    A higher spectral resolution is the main direction of developing remote sensing technology, and it is quite important to set up the digital ground object reflectance spectral database library, one of fundamental research fields in remote sensing application. Remote sensing application has been increasingly relying on ground object spectral characteristics, and quantitative analysis has been developed to a new stage. The present article summarized and systematically introduced the research status quo and development trend of digital ground object reflectance spectral libraries at home and in the world in recent years. Introducing the spectral libraries has been established, including desertification spectral database library, plants spectral database library, geological spectral database library, soil spectral database library, minerals spectral database library, cloud spectral database library, snow spectral database library, the atmosphere spectral database library, rocks spectral database library, water spectral database library, meteorites spectral database library, moon rock spectral database library, and man-made materials spectral database library, mixture spectral database library, volatile compounds spectral database library, and liquids spectral database library. In the process of establishing spectral database libraries, there have been some problems, such as the lack of uniform national spectral database standard and uniform standards for the ground object features as well as the comparability between different databases. In addition, data sharing mechanism can not be carried out, etc. This article also put forward some suggestions on those problems.

  14. Mining Large Scale Tandem Mass Spectrometry Data for Protein Modifications Using Spectral Libraries.

    Science.gov (United States)

    Horlacher, Oliver; Lisacek, Frederique; Müller, Markus

    2016-03-04

    Experimental improvements in post-translational modification (PTM) detection by tandem mass spectrometry (MS/MS) has allowed the identification of vast numbers of PTMs. Open modification searches (OMSs) of MS/MS data, which do not require prior knowledge of the modifications present in the sample, further increased the diversity of detected PTMs. Despite much effort, there is still a lack of functional annotation of PTMs. One possibility to narrow the annotation gap is to mine MS/MS data deposited in public repositories and to correlate the PTM presence with biological meta-information attached to the data. Since the data volume can be quite substantial and contain tens of millions of MS/MS spectra, the data mining tools must be able to cope with big data. Here, we present two tools, Liberator and MzMod, which are built using the MzJava class library and the Apache Spark large scale computing framework. Liberator builds large MS/MS spectrum libraries, and MzMod searches them in an OMS mode. We applied these tools to a recently published set of 25 million spectra from 30 human tissues and present tissue specific PTMs. We also compared the results to the ones obtained with the OMS tool MODa and the search engine X!Tandem.

  15. Rapid Screening of Bovine Milk Oligosaccharides in a Whey Permeate Product and Domestic Animal Milks by Accurate Mass Database and Tandem Mass Spectral Library.

    Science.gov (United States)

    Lee, Hyeyoung; Cuthbertson, Daniel J; Otter, Don E; Barile, Daniela

    2016-08-17

    A bovine milk oligosaccharide (BMO) library, prepared from cow colostrum, with 34 structures was generated and used to rapidly screen oligosaccharides in domestic animal milks and a whey permeate powder. The novel library was entered into a custom Personal Compound Database and Library (PCDL) and included accurate mass, retention time, and tandem mass spectra. Oligosaccharides in minute-sized samples were separated using nanoliquid chromatography (nanoLC) coupled to a high resolution and sensitive quadrupole-Time of Flight (Q-ToF) MS system. Using the PCDL, 18 oligosaccharides were found in a BMO-enriched product obtained from whey permeate processing. The usefulness of the analytical system and BMO library was further validated using milks from domestic sheep and buffaloes. Through BMO PCDL searching, 15 and 13 oligosaccharides in the BMO library were assigned in sheep and buffalo milks, respectively, thus demonstrating significant overlap between oligosaccharides in bovine (cow and buffalo) and ovine (sheep) milks. This method was shown to be an efficient, reliable, and rapid tool to identify oligosaccharide structures using automated spectral matching.

  16. Identification of Leishmania by MALDI-TOF mass spectrometry using a free web-based application and a dedicated mass spectral library.

    Science.gov (United States)

    Lachaud, Laurence; Fernández-Arévalo, Anna; Normand, Anne Cécile; Lami, Patrick; Nabet, Cécile; Donnadieu, Jean Luc; Piarroux, Martine; Djenad, Farid; Cassagne, Carole; Ravel, Christophe; Tebar, Silvia; Llovet, Teresa; Blanchet, Denis; Demar, Magalie; Harrat, Zoubir; Aoun, Karim; Bastien, Patrick; Muñoz, Carmen; Gállego, Montserrat; Piarroux, Renaud

    2017-07-19

    Human leishmaniasis are widely spread diseases with different clinical forms caused by about 20 species within the Leishmania genus. Leishmania species identification is relevant for therapeutic management and prognosis, especially for cutaneous and muco-cutaneous forms. Several methods are available to identify Leishmania species from culture, but they have not been standardized for the majority of the currently described species, with the exception of MultiLocus Enzyme Electrophoresis. Moreover, these techniques are expensive, time-consuming and not available in all laboratories. Within the last decade, mass spectrometry (MS) has been adapted for microorganism identification, including Leishmania However, no commercial reference mass spectral database is available. In this study, a reference mass spectral library (MSL) for Leishmania isolates, accessible through a free web-based application (mass spectral identification, MSI), was constructed and tested. It includes mass spectral data for 33 different Leishmania species, including species that infect humans, animals and phlebotomine vectors. Four laboratories on two continents evaluated MSI performance using 268 samples of which 231 were Leishmania strains. All Leishmania strains, but one, were correctly identified at least at the complex level. A risk of species misidentification within the L. donovani, L. guyanensis and L. braziliensis complexes was observed, as already reported with other techniques. The tested application was reliable, with identification results comparable to those obtained with reference methods, but with a more favorable cost-efficiency ratio. This free online identification system relies on a scalable database and can be implemented directly in the user's computers. Copyright © 2017 American Society for Microbiology.

  17. Customized Consensus Spectral Library Building for Untargeted Quantitative Metabolomics Analysis with Data Independent Acquisition Mass Spectrometry and MetaboDIA Workflow.

    Science.gov (United States)

    Chen, Gengbo; Walmsley, Scott; Cheung, Gemmy C M; Chen, Liyan; Cheng, Ching-Yu; Beuerman, Roger W; Wong, Tien Yin; Zhou, Lei; Choi, Hyungwon

    2017-05-02

    Data independent acquisition-mass spectrometry (DIA-MS) coupled with liquid chromatography is a promising approach for rapid, automatic sampling of MS/MS data in untargeted metabolomics. However, wide isolation windows in DIA-MS generate MS/MS spectra containing a mixed population of fragment ions together with their precursor ions. This precursor-fragment ion map in a comprehensive MS/MS spectral library is crucial for relative quantification of fragment ions uniquely representative of each precursor ion. However, existing reference libraries are not sufficient for this purpose since the fragmentation patterns of small molecules can vary in different instrument setups. Here we developed a bioinformatics workflow called MetaboDIA to build customized MS/MS spectral libraries using a user's own data dependent acquisition (DDA) data and to perform MS/MS-based quantification with DIA data, thus complementing conventional MS1-based quantification. MetaboDIA also allows users to build a spectral library directly from DIA data in studies of a large sample size. Using a marine algae data set, we show that quantification of fragment ions extracted with a customized MS/MS library can provide as reliable quantitative data as the direct quantification of precursor ions based on MS1 data. To test its applicability in complex samples, we applied MetaboDIA to a clinical serum metabolomics data set, where we built a DDA-based spectral library containing consensus spectra for 1829 compounds. We performed fragment ion quantification using DIA data using this library, yielding sensitive differential expression analysis.

  18. USGS Spectral Library Version 7

    Science.gov (United States)

    Kokaly, Raymond F.; Clark, Roger N.; Swayze, Gregg A.; Livo, K. Eric; Hoefen, Todd M.; Pearson, Neil C.; Wise, Richard A.; Benzel, William M.; Lowers, Heather A.; Driscoll, Rhonda L.; Klein, Anna J.

    2017-04-10

    We have assembled a library of spectra measured with laboratory, field, and airborne spectrometers. The instruments used cover wavelengths from the ultraviolet to the far infrared (0.2 to 200 microns [μm]). Laboratory samples of specific minerals, plants, chemical compounds, and manmade materials were measured. In many cases, samples were purified, so that unique spectral features of a material can be related to its chemical structure. These spectro-chemical links are important for interpreting remotely sensed data collected in the field or from an aircraft or spacecraft. This library also contains physically constructed as well as mathematically computed mixtures. Four different spectrometer types were used to measure spectra in the library: (1) Beckman™ 5270 covering the spectral range 0.2 to 3 µm, (2) standard, high resolution (hi-res), and high-resolution Next Generation (hi-resNG) models of Analytical Spectral Devices (ASD) field portable spectrometers covering the range from 0.35 to 2.5 µm, (3) Nicolet™ Fourier Transform Infra-Red (FTIR) interferometer spectrometers covering the range from about 1.12 to 216 µm, and (4) the NASA Airborne Visible/Infra-Red Imaging Spectrometer AVIRIS, covering the range 0.37 to 2.5 µm. Measurements of rocks, soils, and natural mixtures of minerals were made in laboratory and field settings. Spectra of plant components and vegetation plots, comprising many plant types and species with varying backgrounds, are also in this library. Measurements by airborne spectrometers are included for forested vegetation plots, in which the trees are too tall for measurement by a field spectrometer. This report describes the instruments used, the organization of materials into chapters, metadata descriptions of spectra and samples, and possible artifacts in the spectral measurements. To facilitate greater application of the spectra, the library has also been convolved to selected spectrometer and imaging spectrometers sampling and

  19. Extending a Tandem Mass Spectral Library to Include MS2 Spectra of Fragment Ions Produced In-Source and MSn Spectra

    Science.gov (United States)

    Yang, Xiaoyu; Neta, Pedatsur; Stein, Stephen E.

    2017-07-01

    Tandem mass spectral library searching is finding increased use as an effective means of determining chemical identity in mass spectrometry-based omics studies. We previously reported on constructing a tandem mass spectral library that includes spectra for multiple precursor ions for each analyte. Here we report our method for expanding this library to include MS2 spectra of fragment ions generated during the ionization process (in-source fragment ions) as well as MS3 and MS4 spectra. These can assist the chemical identification process. A simple density-based clustering algorithm was used to cluster all significant precursor ions from MS1 scans for an analyte acquired during an infusion experiment. The MS2 spectra associated with these precursor ions were grouped into the same precursor clusters. Subsequently, a new top-down hierarchical divisive clustering algorithm was developed for clustering the spectra from fragmentation of ions in each precursor cluster, including the MS2 spectra of the original precursors and of the in-source fragments as well as the MSn spectra. This algorithm starts with all the spectra of one precursor in one cluster and then separates them into sub-clusters of similar spectra based on the fragment patterns. Herein, we describe the algorithms and spectral evaluation methods for extending the library. The new library features were demonstrated by searching the high resolution spectra of E. coli extracts against the extended library, allowing identification of compounds and their in-source fragment ions in a manner that was not possible before.

  20. XSL : The X-Shooter Spectral Library

    NARCIS (Netherlands)

    Chen, Yanping; Trager, Scott; Peletier, Reynier; Lançon, Ariane

    2011-01-01

    We are building a new spectral library with the X-Shooter instrument on ESO's VLT: XSL, the X-Shooter Spectral Library. We present our progress in building XSL, which covers the wavelength range from the near-UV to the near-IR with a resolution of R~10 000. At the time of writing we have collected s

  1. XSL: The X-Shooter Spectral Library

    NARCIS (Netherlands)

    Chen, Yanping; Trager, Scott; Peletier, Reynier; Lançon, Ariane

    2011-01-01

    We are building a new spectral library with the X-Shooter instrument on ESO's VLT: XSL, the X-Shooter Spectral Library. We present our progress in building XSL, which covers the wavelength range from the near-UV to the near-IR with a resolution of R~10 000. At the time of writing we have collected s

  2. XSL : The X-Shooter Spectral Library

    NARCIS (Netherlands)

    Chen, Yanping; Trager, Scott; Peletier, Reynier; Lan¸con, Ariane

    2011-01-01

    We are building a new spectral library with the X-Shooter instrument on ESO’s VLT: XSL, the X-Shooter Spectral Library. We present our progress in building XSL, which covers the wavelength range from the near-UV to the near-IR with a resolution of R 10000. At the time of writing we have collected sp

  3. On the risk of false positive identification using multiple ion monitoring in qualitative mass spectrometry: large-scale intercomparisons with a comprehensive mass spectral library.

    Science.gov (United States)

    Stein, Stephen E; Heller, David N

    2006-06-01

    Analysts involved in qualitative mass spectrometry have long debated the minimum data requirements for demonstrating that signals from an unknown sample are identical to those from a known compound. Often this process is carried out by comparing a few selected ions acquired by multiple ion monitoring (MIM), with due allowance for expected variability in response. In a few past experiments with electron-ionization mass spectrometry (EI-MS), the number of ions selected and the allowable variability in relative abundance were tested by comparing one spectrum against a library of mass spectra, where library spectra served to represent potential false positive signals in an analysis. We extended these experiments by carrying out large-scale intercomparisons between thousands of spectra and a library of one hundred thousand EI mass spectra. The results were analyzed to gain insights into the identification confidence associated with various numbers of selected ions. A new parameter was investigated for the first time, to take into account that a library spectrum with a different base peak than the search spectrum may still cause a false positive identification. The influence of peak correlation among the specific ions in all the library mass spectra was also studied. Our computations showed that (1) false positive identifications can result from similar compounds, or low-abundance peaks in unrelated compounds if the method calls for detection at very low levels; (2) a MIM method's identification confidence improves in a roughly continuous manner as more ions are monitored, about one order of magnitude for each additional ion selected; (3) full scan spectra still represent the best alternative, if instrument sensitivity is adequate. The use of large scale intercomparisons with a comprehensive library is the only way to provide direct evidence in support of these conclusions, which otherwise depend on the judgment and experience of individual analysts. There are

  4. Storage and retrieval of mass spectral information

    Science.gov (United States)

    Hohn, M. E.; Humberston, M. J.; Eglinton, G.

    1977-01-01

    Computer handling of mass spectra serves two main purposes: the interpretation of the occasional, problematic mass spectrum, and the identification of the large number of spectra generated in the gas-chromatographic-mass spectrometric (GC-MS) analysis of complex natural and synthetic mixtures. Methods available fall into the three categories of library search, artificial intelligence, and learning machine. Optional procedures for coding, abbreviating and filtering a library of spectra minimize time and storage requirements. Newer techniques make increasing use of probability and information theory in accessing files of mass spectral information.

  5. Database and Library Development of Organic Species using Gas Chromatography and Mass Spectral Measurements in Support of the Mars Science Laboratory

    Science.gov (United States)

    Garcia, Raul; Mahaffy, Paul; Misra, Prabhakar

    2010-02-01

    Our work involves the development of an organic contaminants database that will allow us to determine which compounds are found here on Earth and would be inadvertently detected in the Mars soil and gaseous samples as impurities. It will be used for the Sample Analysis at Mars (SAM) instrumentation analysis in the Mars Science Laboratory (MSL) rover scheduled for launch in 2011. In order to develop a comprehensive target database, we utilize the NIST Mass Spectral Library, Automated Mass Spectral Deconvolution and Identification System (AMDIS) and Ion Fingerprint Deconvolution (IFD) software to analyze the GC-MS data. We have analyzed data from commercial samples, such as paint and polymers, which have not been implemented into the rover and are now analyzing actual data from pyrolyzation on the rover. We have successfully developed an initial target compound database that will aid SAM in determining whether the components being analyzed come from Mars or are contaminants from either the rover itself or the Earth environment and are continuing to make improvements and adding data to the target contaminants database. )

  6. USGS Digital Spectral Library splib06a

    Science.gov (United States)

    Clark, Roger N.; Swayze, Gregg A.; Wise, Richard A.; Livo, K. Eric; Hoefen, Todd M.; Kokaly, Raymond F.; Sutley, Stephen J.

    2007-01-01

    Introduction We have assembled a digital reflectance spectral library that covers the wavelength range from the ultraviolet to far infrared along with sample documentation. The library includes samples of minerals, rocks, soils, physically constructed as well as mathematically computed mixtures, plants, vegetation communities, microorganisms, and man-made materials. The samples and spectra collected were assembled for the purpose of using spectral features for the remote detection of these and similar materials. Analysis of spectroscopic data from laboratory, aircraft, and spacecraft instrumentation requires a knowledge base. The spectral library discussed here forms a knowledge base for the spectroscopy of minerals and related materials of importance to a variety of research programs being conducted at the U.S. Geological Survey. Much of this library grew out of the need for spectra to support imaging spectroscopy studies of the Earth and planets. Imaging spectrometers, such as the National Aeronautics and Space Administration (NASA) Airborne Visible/Infra Red Imaging Spectrometer (AVIRIS) or the NASA Cassini Visual and Infrared Mapping Spectrometer (VIMS) which is currently orbiting Saturn, have narrow bandwidths in many contiguous spectral channels that permit accurate definition of absorption features in spectra from a variety of materials. Identification of materials from such data requires a comprehensive spectral library of minerals, vegetation, man-made materials, and other subjects in the scene. Our research involves the use of the spectral library to identify the components in a spectrum of an unknown. Therefore, the quality of the library must be very good. However, the quality required in a spectral library to successfully perform an investigation depends on the scientific questions to be answered and the type of algorithms to be used. For example, to map a mineral using imaging spectroscopy and the mapping algorithm of Clark and others (1990a, 2003b

  7. ICRAF-ISRIC Soil VNIR Spectral Library

    NARCIS (Netherlands)

    Batjes, N.H.

    2014-01-01

    The ICRAF-ISRIC Soil VNIR Spectral Library contains visible near infrared spectra of 4,438 soils selected from the Soil Information System (ISIS) of the International Soil Reference and Information Centre (ISRIC). The samples consist of all physically archived samples at ISRIC in 2004 for which soil

  8. ICRAF-ISRIC Soil VNIR Spectral Library

    NARCIS (Netherlands)

    Batjes, N.H.

    2014-01-01

    The ICRAF-ISRIC Soil VNIR Spectral Library contains visible near infrared spectra of 4,438 soils selected from the Soil Information System (ISIS) of the International Soil Reference and Information Centre (ISRIC). The samples consist of all physically archived samples at ISRIC in 2004 for which soil

  9. A novel spectral library workflow to enhance protein identifications.

    Science.gov (United States)

    Li, Haomin; Zong, Nobel C; Liang, Xiangbo; Kim, Allen K; Choi, Jeong Ho; Deng, Ning; Zelaya, Ivette; Lam, Maggie; Duan, Huilong; Ping, Peipei

    2013-04-09

    The innovations in mass spectrometry-based investigations in proteome biology enable systematic characterization of molecular details in pathophysiological phenotypes. However, the process of delineating large-scale raw proteomic datasets into a biological context requires high-throughput data acquisition and processing. A spectral library search engine makes use of previously annotated experimental spectra as references for subsequent spectral analyses. This workflow delivers many advantages, including elevated analytical efficiency and specificity as well as reduced demands in computational capacity. In this study, we created a spectral matching engine to address challenges commonly associated with a library search workflow. Particularly, an improved sliding dot product algorithm, that is robust to systematic drifts of mass measurement in spectra, is introduced. Furthermore, a noise management protocol distinguishes spectra correlation attributed from noise and peptide fragments. It enables elevated separation between target spectral matches and false matches, thereby suppressing the possibility of propagating inaccurate peptide annotations from library spectra to query spectra. Moreover, preservation of original spectra also accommodates user contributions to further enhance the quality of the library. Collectively, this search engine supports reproducible data analyses using curated references, thereby broadening the accessibility of proteomics resources to biomedical investigators. This article is part of a Special Issue entitled: From protein structures to clinical applications.

  10. Advanced Spectral Library II: Hot Stars

    Science.gov (United States)

    Ayres, Thomas

    2013-10-01

    Stars are the bright matter of the Universe. Without them, it would be a dull and dreary place indeed: no light, no heavy elements, no planets, no life. It also is safe to say that stellar spectroscopy is a cornerstone of astrophysics, providing much of what we know concerning temperatures and masses of stars, their compositions, planets, and the dynamics and evolution of the galaxies they inhabit. This is especially true for the satellite ultraviolet, owing to the rich collection of atomic and ionic transitions found there. Unfortunately, the archive of Space Telescope Imaging Spectrograph rarely achieves the high S/N of the best ground-based spectra, and relatively few objects have the full wavelength coverage for which the powerful, highly multiplexed, second generation Hubble instrument was designed. Our aim is to collect STIS UV echelle spectra - comparable in S/N and resolution to the best ground-based material - for a diverse sample of representative stars, to build an Advanced Spectral Library; a foundation for astrophysical exploration: stellar, interstellar, and beyond. Our first effort, in Cycle 18, involved cool stars. Now we turn attention to the hot side of the H-R diagram.Our Treasury program will provide detailed stellar "atlases," based on advanced processing of the STIS echellegrams. Members of our broad collaboration will analyze these data for specific purposes, such as dynamics of O-star mass-loss; detection of rare species in sharp-lined B stars; and properties and kinematics of local interstellar clouds; but public release {based on the "ASTRAL-I" model} will enable many other investigations by a much wider community, for decades to come.

  11. The Infrared Telescope Facility (IRTF) Spectral Library: Cool Stars

    CERN Document Server

    Rayner, J T; Vacca, W D

    2009-01-01

    We present a 0.8 -5 micron spectral library of 210 cool stars observed at a resolving power of R = lambda / Delta lambda ~ 2000 with the medium-resolution infrared spectrograph, SpeX, at the 3.0 m NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. The stars have well established MK spectral classifications and are mostly restricted to near-solar metallicities. The sample contains the F, G, K, and M spectral types with luminosity classes between I and V, but also includes some AGB, carbon, and S stars. In contrast to some other spectral libraries, the continuum shape of the spectra are measured and preserved in the data reduction process. The spectra are absolutely flux calibrated using Two Micron All Sky Survey (2MASS) photometry. Potential uses of the library include studying the physics of cool stars, classifying and studying embedded young clusters and optically obscured regions of the Galaxy, evolutionary population synthesis to study unresolved stellar populations in optically-obscured regions...

  12. Spectrum-to-Spectrum Searching Using a Proteome-wide Spectral Library*

    Science.gov (United States)

    Yen, Chia-Yu; Houel, Stephane; Ahn, Natalie G.; Old, William M.

    2011-01-01

    The unambiguous assignment of tandem mass spectra (MS/MS) to peptide sequences remains a key unsolved problem in proteomics. Spectral library search strategies have emerged as a promising alternative for peptide identification, in which MS/MS spectra are directly compared against a reference library of confidently assigned spectra. Two problems relate to library size. First, reference spectral libraries are limited to rediscovery of previously identified peptides and are not applicable to new peptides, because of their incomplete coverage of the human proteome. Second, problems arise when searching a spectral library the size of the entire human proteome. We observed that traditional dot product scoring methods do not scale well with spectral library size, showing reduction in sensitivity when library size is increased. We show that this problem can be addressed by optimizing scoring metrics for spectrum-to-spectrum searches with large spectral libraries. MS/MS spectra for the 1.3 million predicted tryptic peptides in the human proteome are simulated using a kinetic fragmentation model (MassAnalyzer version2.1) to create a proteome-wide simulated spectral library. Searches of the simulated library increase MS/MS assignments by 24% compared with Mascot, when using probabilistic and rank based scoring methods. The proteome-wide coverage of the simulated library leads to 11% increase in unique peptide assignments, compared with parallel searches of a reference spectral library. Further improvement is attained when reference spectra and simulated spectra are combined into a hybrid spectral library, yielding 52% increased MS/MS assignments compared with Mascot searches. Our study demonstrates the advantages of using probabilistic and rank based scores to improve performance of spectrum-to-spectrum search strategies. PMID:21532008

  13. The X-shooter Spectral Library and Carbon stars

    NARCIS (Netherlands)

    Gonneau, A.; Lançon, A.; Trager, S. C.; Chen, Y.; Peletier, R.; Aringer, B.; Nowotny, W.; Cambrésy, L.; Martins, F.; Nuss, E.; Palacios, A.

    2013-01-01

    Until recently, most empirical stellar spectral libraries were limited to a certain wavelength range or combined data from different stars, taken by different instruments of which some have low spectral resolution, limiting for instance our ability to analyze galaxies jointly in the ultraviolet, the

  14. Mass Defect from Nuclear Physics to Mass Spectral Analysis

    Science.gov (United States)

    Pourshahian, Soheil

    2017-09-01

    Mass defect is associated with the binding energy of the nucleus. It is a fundamental property of the nucleus and the principle behind nuclear energy. Mass defect has also entered into the mass spectrometry terminology with the availability of high resolution mass spectrometry and has found application in mass spectral analysis. In this application, isobaric masses are differentiated and identified by their mass defect. What is the relationship between nuclear mass defect and mass defect used in mass spectral analysis, and are they the same? [Figure not available: see fulltext.

  15. Identifying proteins in zebrafish embryos using spectral libraries generated from dissected adult organs and tissues.

    Science.gov (United States)

    van der Plas-Duivesteijn, Suzanne J; Mohammed, Yassene; Dalebout, Hans; Meijer, Annemarie; Botermans, Anouk; Hoogendijk, Jordy L; Henneman, Alex A; Deelder, André M; Spaink, Herman P; Palmblad, Magnus

    2014-03-07

    Spectral libraries provide a sensitive and accurate method for identifying peptides from tandem mass spectra, complementary to searching genome-derived databases or sequencing de novo. Their application requires comprehensive libraries including peptides from low-abundant proteins. Here we describe a method for constructing such libraries using biological differentiation to "fractionate" the proteome by harvesting adult organs and tissues and build comprehensive libraries for identifying proteins in zebrafish (Danio rerio) embryos and larvae (an important and widely used model system). Hierarchical clustering using direct comparison of spectra was used to prioritize organ selection. The resulting and publicly available library covers 14,164 proteins, significantly improved the number of peptide-spectrum matches in zebrafish developmental stages, and can be used on data from different instruments and laboratories. The library contains information on tissue and organ expression of these proteins and is also applicable for adult experiments. The approach itself is not limited to zebrafish but would work for any model system.

  16. Spectrum-based method to generate good decoy libraries for spectral library searching in peptide identifications.

    Science.gov (United States)

    Cheng, Chia-Ying; Tsai, Chia-Feng; Chen, Yu-Ju; Sung, Ting-Yi; Hsu, Wen-Lian

    2013-05-01

    As spectral library searching has received increasing attention for peptide identification, constructing good decoy spectra from the target spectra is the key to correctly estimating the false discovery rate in searching against the concatenated target-decoy spectral library. Several methods have been proposed to construct decoy spectral libraries. Most of them construct decoy peptide sequences and then generate theoretical spectra accordingly. In this paper, we propose a method, called precursor-swap, which directly constructs decoy spectral libraries directly at the "spectrum level" without generating decoy peptide sequences by swapping the precursors of two spectra selected according to a very simple rule. Our spectrum-based method does not require additional efforts to deal with ion types (e.g., a, b or c ions), fragment mechanism (e.g., CID, or ETD), or unannotated peaks, but preserves many spectral properties. The precursor-swap method is evaluated on different spectral libraries and the results of obtained decoy ratios show that it is comparable to other methods. Notably, it is efficient in time and memory usage for constructing decoy libraries. A software tool called Precursor-Swap-Decoy-Generation (PSDG) is publicly available for download at http://ms.iis.sinica.edu.tw/PSDG/.

  17. A short review of empirical stellar spectral libraries

    NARCIS (Netherlands)

    Trager, S. C.

    2012-01-01

    I present an overview of empirical stellar spectral libraries, their uses, and (briefly) their history. I focus primarily on their utility for understanding the stellar populations of composite stellar systems, but I show examples of their use for topics ranging from the determination of atmospheric

  18. The Infrared Telescope Facility (IRTF) Spectral Library: Cool Stars

    Science.gov (United States)

    Rayner, John T.; Cushing, Michael C.; Vacca, William D.

    2009-12-01

    We present a 0.8-5 μm spectral library of 210 cool stars observed at a resolving power of R ≡ λ/Δλ ~ 2000 with the medium-resolution infrared spectrograph, SpeX, at the 3.0 m NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii. The stars have well-established MK spectral classifications and are mostly restricted to near-solar metallicities. The sample not only contains the F, G, K, and M spectral types with luminosity classes between I and V, but also includes some AGB, carbon, and S stars. In contrast to some other spectral libraries, the continuum shape of the spectra is measured and preserved in the data reduction process. The spectra are absolutely flux calibrated using the Two Micron All Sky Survey photometry. Potential uses of the library include studying the physics of cool stars, classifying and studying embedded young clusters and optically obscured regions of the Galaxy, evolutionary population synthesis to study unresolved stellar populations in optically obscured regions of galaxies and synthetic photometry. The library is available in digital form from the IRTF Web site.

  19. MaRiMba: A Software Application for Spectral Library-Based MRM Transition List Assembly

    OpenAIRE

    Sherwood, Carly A.; Eastham, Ashley; Lee, Lik Wee; Peterson, Amelia; Eng, Jimmy K.; Shteynberg, David; Mendoza, Luis; Deutsch, Eric W.; Risler, Jenni; Tasman, Natalie; Aebersold, Ruedi; Lam, Henry; Martin, Daniel B

    2009-01-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a targeted analysis method that has been increasingly viewed as an avenue to explore proteomes with unprecedented sensitivity and throughput. We have developed a software tool, called MaRiMba, to automate the creation of explicitly defined MRM transition lists required to program triple quadrupole mass spectrometers in such analyses. MaRiMba creates MRM transition lists from downloaded or custom-built spectral libraries, restricts out...

  20. The Gaia FGK Benchmark Stars - High resolution spectral library

    CERN Document Server

    Blanco-Cuaresma, S; Jofré, P; Heiter, U

    2014-01-01

    Context. An increasing number of high resolution stellar spectra is available today thanks to many past and ongoing spectroscopic surveys. Consequently, numerous methods have been developed in order to perform an automatic spectral analysis on a massive amount of data. When reviewing published results, biases arise and they need to be addressed and minimized. Aims. We are providing a homogeneous library with a common set of calibration stars (known as the Gaia FGK Benchmark Stars) that will allow to assess stellar analysis methods and calibrate spectroscopic surveys. Methods. High resolution and signal-to-noise spectra were compiled from different instruments. We developed an automatic process in order to homogenize the observed data and assess the quality of the resulting library. Results. We built a high quality library that will facilitate the assessment of spectral analyses and the calibration of present and future spectroscopic surveys. The automation of the process minimizes the human subjectivity and e...

  1. Semiblind Hyperspectral Unmixing in the Presence of Spectral Library Mismatches

    Science.gov (United States)

    Fu, Xiao; Ma, Wing-Kin; Bioucas-Dias, Jose M.; Chan, Tsung-Han

    2016-09-01

    The dictionary-aided sparse regression (SR) approach has recently emerged as a promising alternative to hyperspectral unmixing (HU) in remote sensing. By using an available spectral library as a dictionary, the SR approach identifies the underlying materials in a given hyperspectral image by selecting a small subset of spectral samples in the dictionary to represent the whole image. A drawback with the current SR developments is that an actual spectral signature in the scene is often assumed to have zero mismatch with its corresponding dictionary sample, and such an assumption is considered too ideal in practice. In this paper, we tackle the spectral signature mismatch problem by proposing a dictionary-adjusted nonconvex sparsity-encouraging regression (DANSER) framework. The main idea is to incorporate dictionary correcting variables in an SR formulation. A simple and low per-iteration complexity algorithm is tailor-designed for practical realization of DANSER. Using the same dictionary correcting idea, we also propose a robust subspace solution for dictionary pruning. Extensive simulations and real-data experiments show that the proposed method is effective in mitigating the undesirable spectral signature mismatch effects.

  2. A global spectral library to characterize the world's soil

    DEFF Research Database (Denmark)

    A. Viscarra Rossel, Raphael; Behrens, T.; Ben Dor, E.

    2016-01-01

    Soil provides ecosystemservices, supports human health and habitation, stores carbon and regulatesemissions of greenhouse gases. Unprecedented pressures on soil from degradation and urbanization are threatening agroecological balances and food security. It is important that we learn more about soil...... to sustainably manage and preserve it for future generations. To this end, we developed and analyzed a global soil visible–near infrared (vis–NIR) spectral library. It is currently the largest and most diverse database of its kind. We show that the information encoded in the spectra can describe soil composition...

  3. Using fragmentation trees and mass spectral trees for identifying unknown compounds in metabolomics

    Science.gov (United States)

    Vaniya, Arpana

    2015-01-01

    Identification of unknown metabolites is the bottleneck in advancing metabolomics, leaving interpretation of metabolomics results ambiguous. The chemical diversity of metabolism is vast, making structure identification arduous and time consuming. Currently, comprehensive analysis of mass spectra in metabolomics is limited to library matching, but tandem mass spectral libraries are small compared to the large number of compounds found in the biosphere, including xenobiotics. Resolving this bottleneck requires richer data acquisition and better computational tools. Multi-stage mass spectrometry (MSn) trees show promise to aid in this regard. Fragmentation trees explore the fragmentation process, generate fragmentation rules and aid in sub-structure identification, while mass spectral trees delineate the dependencies in multi-stage MS of collision-induced dissociations. This review covers advancements over the past 10 years as a tool for metabolite identification, including algorithms, software and databases used to build and to implement fragmentation trees and mass spectral annotations. PMID:26213431

  4. Predicting soil organic carbon at field scale using a national soil spectral library

    DEFF Research Database (Denmark)

    Peng, Yi; Knadel, Maria; Gislun, Rene

    2013-01-01

    Visible and near infrared diffuse reflectance (vis-NIR) spectroscopy is a low-cost, efficient and accurate soil analysis technique and is thus becoming increasingly popular. Soil spectral libraries are commonly constructed as the basis for estimating soil texture and properties. In this study......, partial least squares regression was used to develop models to predict the soil organic carbon (SOC) content of 35 soil samples from one field using (i) the Danish soil spectral library (2688 samples), (ii) a spiked spectral library (a combination of 30 samples selected from the local area...... and the spectral library, 2718 samples) and (iii) three sub-sets selected from the spectral library. In an attempt to improve prediction accuracy, sub-sets of the soil spectral library were made using three different sample selection methods: those geographically closest (84 samples), those with the same landscape...

  5. A standard for measuring metadata quality in spectral libraries

    Science.gov (United States)

    Rasaiah, B.; Jones, S. D.; Bellman, C.

    2013-12-01

    A standard for measuring metadata quality in spectral libraries Barbara Rasaiah, Simon Jones, Chris Bellman RMIT University Melbourne, Australia barbara.rasaiah@rmit.edu.au, simon.jones@rmit.edu.au, chris.bellman@rmit.edu.au ABSTRACT There is an urgent need within the international remote sensing community to establish a metadata standard for field spectroscopy that ensures high quality, interoperable metadata sets that can be archived and shared efficiently within Earth observation data sharing systems. Metadata are an important component in the cataloguing and analysis of in situ spectroscopy datasets because of their central role in identifying and quantifying the quality and reliability of spectral data and the products derived from them. This paper presents approaches to measuring metadata completeness and quality in spectral libraries to determine reliability, interoperability, and re-useability of a dataset. Explored are quality parameters that meet the unique requirements of in situ spectroscopy datasets, across many campaigns. Examined are the challenges presented by ensuring that data creators, owners, and data users ensure a high level of data integrity throughout the lifecycle of a dataset. Issues such as field measurement methods, instrument calibration, and data representativeness are investigated. The proposed metadata standard incorporates expert recommendations that include metadata protocols critical to all campaigns, and those that are restricted to campaigns for specific target measurements. The implication of semantics and syntax for a robust and flexible metadata standard are also considered. Approaches towards an operational and logistically viable implementation of a quality standard are discussed. This paper also proposes a way forward for adapting and enhancing current geospatial metadata standards to the unique requirements of field spectroscopy metadata quality. [0430] BIOGEOSCIENCES / Computational methods and data processing [0480

  6. Carbon stars in the X-shooter Spectral Library

    CERN Document Server

    Gonneau, A; Trager, S C; Aringer, B; Lyubenova, M; Nowotny, W; Peletier, R F; Prugniel, P; Chen, Y -P; Dries, M; Choudhury, O S; Falcón-Barroso, J; Koleva, M; Meneses-Goytia, S; Sánchez-Blázquez, P; Vazdekis, A

    2016-01-01

    We provide a new collection of spectra of 35 carbon stars obtained with the ESO/VLT X-shooter instrument as part of the X-shooter Spectral Library project. The spectra extend from 0.3$\\mu$m to 2.4$\\mu$m with a resolving power above $\\sim$ 8000. The sample contains stars with a broad range of (J-K) color and pulsation properties located in the Milky Way and the Magellanic Clouds. We show that the distribution of spectral properties of carbon stars at a given (J-K) color becomes bimodal (in our sample) when (J-K) is larger than about 1.5. We describe the two families of spectra that emerge, characterized by the presence or absence of the absorption feature at 1.53$\\mu$m, generally associated with HCN and C$_2$H$_2$. This feature appears essentially only in large-amplitude variables, though not in all observations. Associated spectral signatures that we interpret as the result of veiling by circumstellar matter, indicate that the 1.53$\\mu$m feature might point to episodes of dust production in carbon-rich Miras.

  7. Characterizing Vaccinium berry Standard Reference Materials by GC-MS using NIST spectral libraries.

    Science.gov (United States)

    Lowenthal, Mark S; Andriamaharavo, Nirina R; Stein, Stephen E; Phinney, Karen W

    2013-05-01

    A gas chromatography-mass spectrometry (GC-MS)-based method was developed for qualitative characterization of metabolites found in Vaccinium fruit (berry) dietary supplement Standard Reference Materials (SRMs). Definitive identifications are provided for 98 unique metabolites determined among six Vaccinium-related SRMs. Metabolites were enriched using an organic liquid/liquid extraction, and derivatized prior to GC-MS analysis. Electron ionization (EI) fragmentation spectra were searched against EI spectra of authentic standards compiled in the National Institute of Standards and Technology's mass spectral libraries, as well as spectra selected from the literature. Metabolite identifications were further validated using a retention index match along with prior probabilities and were compared with results obtained in a previous effort using collision-induced dissociation (CID) MS/MS datasets from liquid chromatography coupled to mass spectrometry experiments. This manuscript describes a nontargeted metabolite profile of Vaccinium materials, compares results among related materials and from orthogonal experimental platforms, and discusses the feasibility and development of using mass spectral library matching for nontargeted metabolite identification.

  8. The HST Treasury "Advanced Spectral Library" (ASTRAL) Programs

    CERN Document Server

    Carpenter, Kenneth G

    2014-01-01

    The "Advanced Spectral Library (ASTRAL)" Project (PI = T. Ayres) consists of two Treasury Programs: the Cycle 18 "Cool Stars" (GO-12278) Program and the Cycle 21 "Hot Stars" (GO-13346) Program. The primary goal of these programs is to collect, for the use of the astronomical community over the coming decades, a definitive set of representative, high-resolution (R~30,000-100,000), high signal/noise (S/N>100) spectra, with full UV coverage (~1150 - 3100 A) of prototypical stars across the HR diagram, utilizing the high-performance Space Telescope Imaging Spectrograph (STIS). The Cycle 18 program obtained spectra of 8 F-M evolved late-type stars, while the Cycle 21 program is in the process of observing 21 early-type stars, which span a broad range of spectral types between early-O and early-A. All of these data will be available from the HST archive and, in post-processed and merged form, at http://casa.colorado.edu/~ayres/ASTRAL/. These data will enable investigations of a broad range of problems -- stellar, i...

  9. The volatile compound BinBase mass spectral database

    Directory of Open Access Journals (Sweden)

    Barupal Dinesh K

    2011-08-01

    Full Text Available Abstract Background Volatile compounds comprise diverse chemical groups with wide-ranging sources and functions. These compounds originate from major pathways of secondary metabolism in many organisms and play essential roles in chemical ecology in both plant and animal kingdoms. In past decades, sampling methods and instrumentation for the analysis of complex volatile mixtures have improved; however, design and implementation of database tools to process and store the complex datasets have lagged behind. Description The volatile compound BinBase (vocBinBase is an automated peak annotation and database system developed for the analysis of GC-TOF-MS data derived from complex volatile mixtures. The vocBinBase DB is an extension of the previously reported metabolite BinBase software developed to track and identify derivatized metabolites. The BinBase algorithm uses deconvoluted spectra and peak metadata (retention index, unique ion, spectral similarity, peak signal-to-noise ratio, and peak purity from the Leco ChromaTOF software, and annotates peaks using a multi-tiered filtering system with stringent thresholds. The vocBinBase algorithm assigns the identity of compounds existing in the database. Volatile compound assignments are supported by the Adams mass spectral-retention index library, which contains over 2,000 plant-derived volatile compounds. Novel molecules that are not found within vocBinBase are automatically added using strict mass spectral and experimental criteria. Users obtain fully annotated data sheets with quantitative information for all volatile compounds for studies that may consist of thousands of chromatograms. The vocBinBase database may also be queried across different studies, comprising currently 1,537 unique mass spectra generated from 1.7 million deconvoluted mass spectra of 3,435 samples (18 species. Mass spectra with retention indices and volatile profiles are available as free download under the CC-BY agreement (http

  10. The Infrared Telescope Facility (IRTF) spectral library: spectral diagnostics for cool stars

    CERN Document Server

    Cesetti, Mary; Ivanov, V D; Morelli, L; Corsini, E M; Bonta`, E Dalla

    2012-01-01

    The near-infrared (NIR) wavelength range offers some unique spectral features, and it is less prone to the extinction than the optical one. Recently, the first flux calibrated NIR library of cool stars from the NASA Infrared Telescope Facility (IRTF) have become available, and it has not been fully exploited yet. We want to develop spectroscopic diagnostics for stellar physical parameters based on features in the wavelength range 1-5 micron. In this work we test the technique in the I and K bands. The study of the Y, J, H, and L bands will be presented in the following paper. An objective method for semi-empirical definition of spectral features sensitive to various physical parameters is applied to the spectra. It is based on sensitivity map--i.e., derivative of the flux in the spectra with respect to the stellar parameters at a fixed wavelength. New optimized indices are defined and their equivalent widths (EWs) are measured. A number of sensitive features to the effective temperature and surface gravity ar...

  11. DEVELOPMENT AND UTILIZATION OF URBAN SPECTRAL LIBRARY FOR REMOTE SENSING OF URBAN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Nurul Ezaty Mohd Nasarudin

    2011-01-01

    Full Text Available Hyperspectral technology is useful for urban studies due to its capability in examining detailed spectral characteristics of urban materials. This study aims to develop a spectral library of urban materials and demonstrate its application in remote sensing analysis of an urban environment. Field measurements were conducted by using ASD FieldSpec 3 Spectroradiometer with wavelength range from 350 to 2500 nm. The spectral reflectance curves of urban materials were interpreted and analyzed. A collection of 22 spectral data was compiled into a spectral library. The spectral library was put to practical use by utilizing the reference spectra for WorldView-2 satellite image classification which demonstrates the usability of such infrastructure to facilitatefurther progress of remote sensing applications in Malaysia.

  12. DEVELOPMENT AND UTILIZATION OF URBAN SPECTRAL LIBRARY FOR REMOTE SENSING OF URBAN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Nurul Ezaty Mohd Nasarudin

    2011-06-01

    Full Text Available Hyperspectral technology is useful for urban studies due to its capability in examining detailed spectral characteristics of urban materials. This study aims to develop a spectral library of urban materials and demonstrate its application in remote sensing analysis of an urban environment. Field measurements were conducted by using ASD FieldSpec 3 Spectroradiometer with wavelength range from 350 to 2500 nm. The spectral reflectance curves of urban materials were interpreted and analyzed. A collection of 22 spectral data was compiled into a spectral library. The spectral library was put to practical use by utilizing the reference spectra for WorldView-2 satellite image classification which demonstrates the usability of such infrastructure to facilitate further progress of remote sensing applications in Malaysia.

  13. Electron-energy-loss spectral library and its application to materials science

    Energy Technology Data Exchange (ETDEWEB)

    Zaluzec, N.J.

    1983-09-01

    An electron energy loss spectral library can be an invaluable tool in materials research from a fundamental as well as a practical standpoint. Although it will not alleviate all the complications associated with quantification, this type of library can help to elucidate details of spectral profiles previously found intractable. This work was supported by the US Department of Energy. The author also wishes to express his gratitude to the organizing committee for partial financial support provided to attend this meeting.

  14. Single stellar populations in the near-infrared. I. Preparation of the IRTF spectral stellar library

    NARCIS (Netherlands)

    Meneses-Goytia, S.; Peletier, R. F.; Trager, S. C.; Falcón-Barroso, J.; Koleva, M.; Vazdekis, A.

    2015-01-01

    We present a detailed study of the stars of the NASA InfraRed Telescope Facility (IRTF) spectral library to understand its full extent and reliability for use with stellar population (SP) modeling. The library consist of 210 stars, with a total of 292 spectra, covering the wavelength range of 0.94 t

  15. ProMEX: a mass spectral reference database for proteins and protein phosphorylation sites

    Directory of Open Access Journals (Sweden)

    Selbig Joachim

    2007-06-01

    Full Text Available Abstract Background In the last decade, techniques were established for the large scale genome-wide analysis of proteins, RNA, and metabolites, and database solutions have been developed to manage the generated data sets. The Golm Metabolome Database for metabolite data (GMD represents one such effort to make these data broadly available and to interconnect the different molecular levels of a biological system 1. As data interpretation in the light of already existing data becomes increasingly important, these initiatives are an essential part of current and future systems biology. Results A mass spectral library consisting of experimentally derived tryptic peptide product ion spectra was generated based on liquid chromatography coupled to ion trap mass spectrometry (LC-IT-MS. Protein samples derived from Arabidopsis thaliana, Chlamydomonas reinhardii, Medicago truncatula, and Sinorhizobium meliloti were analysed. With currently 4,557 manually validated spectra associated with 4,226 unique peptides from 1,367 proteins, the database serves as a continuously growing reference data set and can be used for protein identification and quantification in uncharacterized biological samples. For peptide identification, several algorithms were implemented based on a recently published study for peptide mass fingerprinting 2 and tested for false positive and negative rates. An algorithm which considers intensity distribution for match correlation scores was found to yield best results. For proof of concept, an LC-IT-MS analysis of a tryptic leaf protein digest was converted to mzData format and searched against the mass spectral library. The utility of the mass spectral library was also tested for the identification of phosphorylated tryptic peptides. We included in vivo phosphorylation sites of Arabidopsis thaliana proteins and the identification performance was found to be improved compared to genome-based search algorithms. Protein identification by Pro

  16. Selection of neutral losses and characteristic ions for mass spectral classifier.

    Science.gov (United States)

    Zhang, Liangxiao; Liang, Yizeng; Chen, Aiming

    2009-08-01

    Gas chromatography-mass spectrometry (GC-MS) is widely used in many fields because of its high sensitivity, high resolution and reproducibility. The major challenge of this analytical technology is the identification of components in complex samples. Generally, mass spectral library searching is commonly employed to assist in the identification of unknown spectra. However, this widely available method just provides a hit-list of candidates ordered by their numerical similarity indices. When an unknown compound has many isomeric compounds or is absent from the reference library, this approach might be less useful. Classification of mass spectra, a complementary technique to the library searching, is beneficial to computer-aided mass spectral interpretation but suffers from the fact that the variables used in the classifier are usually uninterpretable. In this study, a novel classifier is built based on data mining and feature analysis. In this classifier, the neutral loss is skillfully used to identify the differences between mass spectra of alcohols and ethers in the data set. After comparison with two chemometric methods, Fisher ratios linear discriminant analysis (LDA) and genetic algorithm partial least squares discriminant (GA-DPLS) analysis, it is found that our method achieves a better predictive ability. More importantly, this method is able to predict whether compounds could be classified correctly or not.

  17. Spectral Band Selection for Urban Material Classification Using Hyperspectral Libraries

    Science.gov (United States)

    Le Bris, A.; Chehata, N.; Briottet, X.; Paparoditis, N.

    2016-06-01

    In urban areas, information concerning very high resolution land cover and especially material maps are necessary for several city modelling or monitoring applications. That is to say, knowledge concerning the roofing materials or the different kinds of ground areas is required. Airborne remote sensing techniques appear to be convenient for providing such information at a large scale. However, results obtained using most traditional processing methods based on usual red-green-blue-near infrared multispectral images remain limited for such applications. A possible way to improve classification results is to enhance the imagery spectral resolution using superspectral or hyperspectral sensors. In this study, it is intended to design a superspectral sensor dedicated to urban materials classification and this work particularly focused on the selection of the optimal spectral band subsets for such sensor. First, reflectance spectral signatures of urban materials were collected from 7 spectral libraires. Then, spectral optimization was performed using this data set. The band selection workflow included two steps, optimising first the number of spectral bands using an incremental method and then examining several possible optimised band subsets using a stochastic algorithm. The same wrapper relevance criterion relying on a confidence measure of Random Forests classifier was used at both steps. To cope with the limited number of available spectra for several classes, additional synthetic spectra were generated from the collection of reference spectra: intra-class variability was simulated by multiplying reference spectra by a random coefficient. At the end, selected band subsets were evaluated considering the classification quality reached using a rbf svm classifier. It was confirmed that a limited band subset was sufficient to classify common urban materials. The important contribution of bands from the Short Wave Infra-Red (SWIR) spectral domain (1000-2400 nm) to material

  18. Mass Spectral Analysis of PAMPRE Tholins

    Science.gov (United States)

    Horst, Sarah; Adams, R.; Carrasco, N.; Djevahirdjian, L.; Pernot, P.; Sciamma-O'Brien, E.; Szopa, C.; Thissen, R.; Vuitton, V.; Yelle, R. V.

    2009-09-01

    The destruction of N2 and CH4 and subsequent complex chemical processes lead to the formation of organic aerosols in Titan's atmosphere. To further the understanding of the formation and composition of these aerosols, laboratory experiments have been designed to produce aerosols under Titan atmospheric conditions. We have characterized tholins generated by the PAMPRE (Production d'Aérosols en Microgravité par Plasma REactif) experiment. The PAMPRE experiment uses capacitively coupled RF plasma discharge to initiate the chemistry between N2 and CH4 that leads to the production of solid particles (tholins). The tholins form and grow while levitated in the plasma, which minimizes any possible wall effects. Tholins were generated using 3 different N2/CH4 gas mixtures: 98/2, 95/5, 90/10. The tholins were characterized using the LTQ-Orbitrap XL mass spectrometer, which has a resolving power of 1.e5 at 400 amu and accuracy in exact mass determination of 2 ppm. Thousands of molecules have been identified ranging in mass from 50 to 800 amu. The spectra exhibit groups of peaks with a mass periodicity of 13.5, which provides insight into the chemical processes involved in tholin synthesis. The application of the knowledge gained from these experiments to the study of corresponding processes on Titan will be briefly discussed.

  19. CARS Spectral Fitting with Multiple Resonant Species using Sparse Libraries

    Science.gov (United States)

    Cutler, Andrew D.; Magnotti, Gaetano

    2010-01-01

    The dual pump CARS technique is often used in the study of turbulent flames. Fast and accurate algorithms are needed for fitting dual-pump CARS spectra for temperature and multiple chemical species. This paper describes the development of such an algorithm. The algorithm employs sparse libraries, whose size grows much more slowly with number of species than a conventional library. The method was demonstrated by fitting synthetic "experimental" spectra containing 4 resonant species (N2, O2, H2 and CO2), both with noise and without it, and by fitting experimental spectra from a H2-air flame produced by a Hencken burner. In both studies, weighted least squares fitting of signal, as opposed to least squares fitting signal or square-root signal, was shown to produce the least random error and minimize bias error in the fitted parameters.

  20. Driver study oriented to the vegetation spectral library creation

    Directory of Open Access Journals (Sweden)

    Marco Marchetti

    2008-01-01

    Full Text Available By utilising the Italian component of the Image & Corine Land Cover 2000 project (I&CLC2000 it has been proposed the creation of a database containing vegetation spectral signature, by using Landsat 7 ETM+ images acquired during the summer of 1999-2001 and covering the whole Italian territory, in order to contribute on the improving of the land cover/use classification processes. The initial project structure foresees both the spectral and statistical results analysis of beechwood land cover (CLC2000 3.1.1.5 class. For the spectral analysis it has been utilised the vector layer retailed from the CLC2000 and applied on the Landsat images. The statistical analysis on the selected areas has been effectuated by non-parametric test (Kruskal-Wallis ANOVA. In order to implement the spectral dataset of land vegetation component, this study aims at the chestnut analysis (CLC2000 3.1.1.4 class, by using the same methodology previously applied to the beachwood.

  1. Precision Stellar Characterization of FGKM Stars using an Empirical Spectral Library

    Science.gov (United States)

    Yee, Samuel W.; Petigura, Erik A.; von Braun, Kaspar

    2017-02-01

    Classification of stars, by comparing their optical spectra to a few dozen spectral standards, has been a workhorse of observational astronomy for more than a century. Here, we extend this technique by compiling a library of optical spectra of 404 touchstone stars observed with Keck/HIRES by the California Planet Search. The spectra have high resolution (R ≈ 60,000), high signal-to-noise ratio (S/N ≈ 150/pixel), and are registered onto a common wavelength scale. The library stars have properties derived from interferometry, asteroseismology, LTE spectral synthesis, and spectrophotometry. To address a lack of well-characterized late-K dwarfs in the literature, we measure stellar radii and temperatures for 23 nearby K dwarfs, using modeling of the spectral energy distribution and Gaia parallaxes. This library represents a uniform data set spanning the spectral types ∼M5–F1 (T eff ≈ 3000–7000 K, R ⋆ ≈ 0.1–16 R ⊙). We also present “Empirical SpecMatch” (SpecMatch-Emp), a tool for parameterizing unknown spectra by comparing them against our spectral library. For FGKM stars, SpecMatch-Emp achieves accuracies of 100 K in effective temperature (T eff), 15% in stellar radius (R ⋆), and 0.09 dex in metallicity ([Fe/H]). Because the code relies on empirical spectra it performs particularly well for stars ∼K4 and later, which are challenging to model with existing spectral synthesizers, reaching accuracies of 70 K in T eff, 10% in R ⋆, and 0.12 dex in [Fe/H]. We also validate the performance of SpecMatch-Emp, finding it to be robust at lower spectral resolution and S/N, enabling the characterization of faint late-type stars. Both the library and stellar characterization code are publicly available.

  2. Quality control for building libraries from electrospray ionization tandem mass spectra.

    Science.gov (United States)

    Yang, Xiaoyu; Neta, Pedatsur; Stein, Stephen E

    2014-07-01

    Electrospray ionization (ESI) tandem mass spectrometry coupled with liquid chromatography is a routine technique for identifying and quantifying compounds in complex mixtures. The identification step can be aided by matching acquired tandem mass spectra (MS(2)) against reference library spectra as is routine for electron ionization (EI) spectra from gas chromatography/mass spectrometry (GC/MS). However, unlike the latter spectra, ESI MS(2) spectra are likely to originate from various precursor ions for a given target molecule and may be acquired at varying energies and resolutions and have characteristic noise signatures, requiring processing methods very different from EI to obtain complete and high quality reference spectra for individual analytes. This paper presents procedures developed for creating a tandem mass spectral library that addresses these factors. Library building begins by acquiring MS(2) spectra for all major MS(1) peaks in an infusion run, followed by assigning MS(2) spectra to clusters and creating a consensus spectrum for each. Intensity-based constraints for cluster membership were developed, as well as peak testing to recognize and eliminate suspect peaks and reduce noise. Consensus spectra were then examined by a human evaluator using a number of criteria, including a fraction of annotated peaks and consistency of spectra for a given ion at different energies. These methods have been developed and used to build a library from >9000 compounds, yielding 230,000 spectra.

  3. MaRiMba: a software application for spectral library-based MRM transition list assembly.

    Science.gov (United States)

    Sherwood, Carly A; Eastham, Ashley; Lee, Lik Wee; Peterson, Amelia; Eng, Jimmy K; Shteynberg, David; Mendoza, Luis; Deutsch, Eric W; Risler, Jenni; Tasman, Natalie; Aebersold, Ruedi; Lam, Henry; Martin, Daniel B

    2009-10-01

    Multiple reaction monitoring mass spectrometry (MRM-MS) is a targeted analysis method that has been increasingly viewed as an avenue to explore proteomes with unprecedented sensitivity and throughput. We have developed a software tool, called MaRiMba, to automate the creation of explicitly defined MRM transition lists required to program triple quadrupole mass spectrometers in such analyses. MaRiMba creates MRM transition lists from downloaded or custom-built spectral libraries, restricts output to specified proteins or peptides, and filters based on precursor peptide and product ion properties. MaRiMba can also create MRM lists containing corresponding transitions for isotopically heavy peptides, for which the precursor and product ions are adjusted according to user specifications. This open-source application is operated through a graphical user interface incorporated into the Trans-Proteomic Pipeline, and it outputs the final MRM list to a text file for upload to MS instruments. To illustrate the use of MaRiMba, we used the tool to design and execute an MRM-MS experiment in which we targeted the proteins of a well-defined and previously published standard mixture.

  4. New H-band Stellar Spectral Libraries for the SDSS-III/APOGEE survey

    CERN Document Server

    Zamora, O; Prieto, C Allende; Carrera, R; Koesterke, L; Edvardsson, B; Castelli, F; Plez, B; Bizyaev, D; Cunha, K; Perez, A E Garcia; Gustafsson, B; Holtzman, J A; Lawler, J E; Majewski, S R; Manchado, A; Meszaros, Sz; Shane, N; Shetrone, M; Smith, V V; Zasowski, G

    2015-01-01

    The Sloan Digital Sky Survey--III (SDSS--III) Apache Point Observatory Galactic Evolution Experiment (APOGEE) has obtained high resolution (R $\\sim$ 22,500), high signal-to-noise ($>$ 100) spectra in the H$-$band spectral region ($\\sim$1.5$-$1.7 $\\mu$m) for about 146,000 stars in the Milky Way galaxy. We have computed specific spectral libraries with effective temperature ($T\\rm{_{eff}}$) ranging from 3500 to 8000 K for the automated chemical analysis of the survey data. The spectral libraries, used to derive stellar parameters and abundances from the APOGEE spectra in the SDSS--III data release 12 (DR12), are based on ATLAS9 model atmospheres and the ASS$\\epsilon$T spectral synthesis code. We present a second set of stellar spectral libraries based on MARCS model atmospheres and the spectral synthesis code Turbospectrum. The ATLAS9/ASS$\\epsilon$T ($T\\rm{_{eff}}$ = 3500$-$8000 K) and MARCS/Turbospectrum ($T\\rm{_{eff}}$ = 3500$-$5500 K) grids of synthetic spectra cover a wide range of metallicity ($-$2.5 $\\leq...

  5. MapReduce implementation of a hybrid spectral library-database search method for large-scale peptide identification.

    Science.gov (United States)

    Kalyanaraman, Ananth; Cannon, William R; Latt, Benjamin; Baxter, Douglas J

    2011-11-01

    A MapReduce-based implementation called MR-MSPolygraph for parallelizing peptide identification from mass spectrometry data is presented. The underlying serial method, MSPolygraph, uses a novel hybrid approach to match an experimental spectrum against a combination of a protein sequence database and a spectral library. Our MapReduce implementation can run on any Hadoop cluster environment. Experimental results demonstrate that, relative to the serial version, MR-MSPolygraph reduces the time to solution from weeks to hours, for processing tens of thousands of experimental spectra. Speedup and other related performance studies are also reported on a 400-core Hadoop cluster using spectral datasets from environmental microbial communities as inputs. The source code along with user documentation are available on http://compbio.eecs.wsu.edu/MR-MSPolygraph. ananth@eecs.wsu.edu; william.cannon@pnnl.gov. Supplementary data are available at Bioinformatics online.

  6. Grand Symmetry, Spectral Action, and the Higgs mass

    CERN Document Server

    Devastato, Agostino; Martinetti, Pierre

    2013-01-01

    In the context of the spectral action and noncommutative geometry approach to the standard model, we build a model based on a larger symmetry. This symmetry satisfies all the conditions to have a noncommutative manifold, and mixes gauge and spin degrees of freedom and does not introduce extra fermions. With this "grand symmetry" it is natural to have the scalar field necessary to obtain the Higgs mass in the vicinity of 126 GeV. The spectral action breaks the grand symmetry to the standard model algebra. This breaking also gives the spin structure of spacetime as broken symmetry.

  7. Spectral unmixing of urban land cover using a generic library approach

    Science.gov (United States)

    Degerickx, Jeroen; Lordache, Marian-Daniel; Okujeni, Akpona; Hermy, Martin; van der Linden, Sebastian; Somers, Ben

    2016-10-01

    Remote sensing based land cover classification in urban areas generally requires the use of subpixel classification algorithms to take into account the high spatial heterogeneity. These spectral unmixing techniques often rely on spectral libraries, i.e. collections of pure material spectra (endmembers, EM), which ideally cover the large EM variability typically present in urban scenes. Despite the advent of several (semi-) automated EM detection algorithms, the collection of such image-specific libraries remains a tedious and time-consuming task. As an alternative, we suggest the use of a generic urban EM library, containing material spectra under varying conditions, acquired from different locations and sensors. This approach requires an efficient EM selection technique, capable of only selecting those spectra relevant for a specific image. In this paper, we evaluate and compare the potential of different existing library pruning algorithms (Iterative Endmember Selection and MUSIC) using simulated hyperspectral (APEX) data of the Brussels metropolitan area. In addition, we develop a new hybrid EM selection method which is shown to be highly efficient in dealing with both imagespecific and generic libraries, subsequently yielding more robust land cover classification results compared to existing methods. Future research will include further optimization of the proposed algorithm and additional tests on both simulated and real hyperspectral data.

  8. Rapid screening of anti-infective drug products for counterfeits using Raman spectral library-based correlation methods.

    Science.gov (United States)

    Loethen, Yvette L; Kauffman, John F; Buhse, Lucinda F; Rodriguez, Jason D

    2015-11-07

    A new spectral library-based approach that is capable of screening a diverse set of finished drug products using only an active pharmaceutical ingredient spectral library is described in this paper. This approach obviates the need for a comprehensive drug product library, thereby streamlining the use of spectral library-based tests for anti-counterfeiting efforts, specifically to target finished drug products containing the wrong active ingredient or no active ingredient at all. Both laboratory-based and portable spectrometers are used in the study to demonstrate the usefulness and transferability of the spectral correlation method for field screening. The spectral correlation between the active pharmaceutical ingredient and finished drug product spectra is calculated using both full spectral analysis and targeted spectral regions analysis of six types of antimalarial, antibiotic and antiviral products. The spectral regions were determined using a moving window spectral correlation algorithm, and the use of specific spectral regions is shown to be crucial in screening finished drug products using only the active pharmaceutical ingredient spectrum. This comprehensive screening spectral correlation method is tested on seven different validation samples from different manufacturers as those used to develop the method, as well as simulated counterfeits which were prepared to mimic falsified drugs containing no active ingredient. The spectral correlation method is successful in correctly identifying 100% of the authentic products and simulated counterfeit samples tested.

  9. Large blue isocurvature spectral index signals time-dependent mass

    Science.gov (United States)

    Chung, Daniel J. H.

    2016-08-01

    We show that if a spectator linear isocurvature dark matter field degree of freedom has a constant mass through its entire evolution history, the maximum measurable isocurvature spectral index that is consistent with the current tensor-to-scalar ratio bound of about r ≲0.1 is about nI≲2.4 , even if experiments can be sensitive to a 10-6 contamination of the predominantly adiabatic power spectrum with an isocurvature power spectrum at the shortest observable length scales. Hence, any foreseeable future measurement of a blue isocurvature spectral index larger than ˜2.4 may provide nontrivial evidence for dynamical degrees of freedom with time-dependent masses during inflation. The bound is not sensitive to the details of the reheating scenario and can be made mildly smaller if r is better constrained in the future.

  10. Development of a Danish national vis—NIR soil spectral library for SOC determination

    DEFF Research Database (Denmark)

    Knadel, Maria; Deng, Fan; Greve, Mogens Humlekrog;

    The development of a soil spectral library is a prerequisite for using vis-NIR spectroscopy for soil analysis. The aim of this study is twofold: (i) to create a Danish national soil library with a main focus on building a model for SOC determination and (ii) to test the feasibility of using...... the library to predict SOC from new dry and moist samples, before and after spiking the library with additional local samples. Soils spectra were obtained using Labspec 5100 (350-2500 nm) vis-NIR sensor. The best validation model resulted in RMSEP value of 0.31, R2 value of 0.79 and RPD value of 2.......3. The prediction on independent data resulted in very similar results: RMSEP=0.29, R2 of 0.81 and RPD of 2.4. Before spiking the library moderate SOC predictions were obtained for the new dry soils. Prediction on moist samples however, required prior spiking the global library with moist samples from the new...

  11. Large Blue Spectral Isocurvature Spectral Index Signals Time-Dependent Mass

    CERN Document Server

    Chung, Daniel J H

    2015-01-01

    We show that if a spectator linear isocurvature dark matter field degree of freedom has a constant mass through its entire evolution history, the maximum measurable isocurvature spectral index that is consistent with the current tensor-to-scalar ratio bound is about 2.4, even if experiments can be sensitive to a $10^{-6}$ contamination of the predominantly adiabatic power spectrum with an isocurvature power spectrum at the shortest observable length scales. Hence, any foreseeable future measurement of a blue isocurvature spectral index larger than about 2.4 may provide nontrivial evidence for dynamical degrees of freedom with time-dependent masses during inflation. The bound is not sensitive to the details of the reheating scenario and can be made mildly smaller if the tensor-to-scalar ratio is better constrained in the future.

  12. Revived STIS. II. Properties of Stars in the Next Generation Spectral Library

    Science.gov (United States)

    Heap, Sara R.; Lindler, D.

    2010-01-01

    Spectroscopic surveys of galaxies at high redshift will bring the rest-frame ultraviolet into view of large, ground-based telescopes. The UV-blue spectral region is rich in diagnostics, but these diagnostics have not yet been calibrated in terms of the properties of the responsible stellar population(s). Such calibrations are now possible with Hubble's Next Generation Spectral Library (NGSL). The NGSL contains UV-optical spectra (0.2 - 1.0 microns) of 374 stars having a wide range in temperature, luminosity, and metallicity. We will describe our work to derive basic stellar parameters from NGSL spectra using modern model spectra and to use these stellar parameters to develop UV-blue spectral diagnostics.

  13. A spectral differential characterization of low-mass companions

    Directory of Open Access Journals (Sweden)

    Lyubchik Y.

    2013-04-01

    Full Text Available We present a new approach with which the dynamical mass of low-mass companions around cool stars can be found. In order to discover companions to late-type stars the stellar spectrum is removed. For this we substract two spectra obtained at different orbital phases from each other in order to discover the companion spectrum in the difference spectrum in which the companion lines appear twice (positive and negative signal. The resulting radial velocity difference of these two signals provides the true mass of the companion. For our test case GJ1046, an M2V dwarf with a low-mass companion that most likely is a brown dwarf we select the CO line region in the K-band. We show that the dynamical mass of a faint companion to an M dwarf can be determined using our spectral differential technique. Only if the companion rotates rapidly and has a small radial velocity amplitude due to a high mass, does blending occur for all lines so that our approach fails. In addition to determining the companion mass, we restore the single companion spectrum from the difference spectrum using singular value decomposition.

  14. On the construction of a new stellar classification template library for the LAMOST spectral analysis pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Peng; Luo, Ali; Li, Yinbi; Tu, Liangping; Wang, Fengfei; Zhang, Jiannan; Chen, Xiaoyan; Hou, Wen; Kong, Xiao; Wu, Yue; Zuo, Fang; Yi, Zhenping; Zhao, Yongheng; Chen, Jianjun; Du, Bing; Guo, Yanxin; Ren, Juanjuan [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Pan, Jingchang; Jiang, Bin; Liu, Jie, E-mail: lal@nao.cas.cn, E-mail: weipeng@nao.cas.cn [School of Mechanical, Electrical, and Information Engineering, Shandong University, Weihai 264209 (China); and others

    2014-05-01

    The LAMOST spectral analysis pipeline, called the 1D pipeline, aims to classify and measure the spectra observed in the LAMOST survey. Through this pipeline, the observed stellar spectra are classified into different subclasses by matching with template spectra. Consequently, the performance of the stellar classification greatly depends on the quality of the template spectra. In this paper, we construct a new LAMOST stellar spectral classification template library, which is supposed to improve the precision and credibility of the present LAMOST stellar classification. About one million spectra are selected from LAMOST Data Release One to construct the new stellar templates, and they are gathered in 233 groups by two criteria: (1) pseudo g – r colors obtained by convolving the LAMOST spectra with the Sloan Digital Sky Survey ugriz filter response curve, and (2) the stellar subclass given by the LAMOST pipeline. In each group, the template spectra are constructed using three steps. (1) Outliers are excluded using the Local Outlier Probabilities algorithm, and then the principal component analysis method is applied to the remaining spectra of each group. About 5% of the one million spectra are ruled out as outliers. (2) All remaining spectra are reconstructed using the first principal components of each group. (3) The weighted average spectrum is used as the template spectrum in each group. Using the previous 3 steps, we initially obtain 216 stellar template spectra. We visually inspect all template spectra, and 29 spectra are abandoned due to low spectral quality. Furthermore, the MK classification for the remaining 187 template spectra is manually determined by comparing with 3 template libraries. Meanwhile, 10 template spectra whose subclass is difficult to determine are abandoned. Finally, we obtain a new template library containing 183 LAMOST template spectra with 61 different MK classes by combining it with the current library.

  15. Analytical utility of mass spectral binning in proteomic experiments by SPectral Immonium Ion Detection (SPIID)

    DEFF Research Database (Denmark)

    Kelstrup, Christian D; Freese, Christian; Heck, Albert J R;

    2014-01-01

    interpretation and determination of the chemical composition for the majority of detected fragment ions is feasible. Collectively we present a freely available software tool that allows for comprehensive and automatic analysis of analogous product ions in tandem mass spectra, and systematic mapping......, increasing the demand for advanced data interpretation. Several PTMs are known to generate unique fragment ions during tandem mass spectrometry (MS/MS), the so-called diagnostic ions, which unequivocally identifies that a given mass spectrum relates to a specific PTM. Although such ions hold tremendous...... analytical advantages, algorithms to decipher MS/MS spectra for the presence of diagnostic ions in an unbiased manner are currently lacking. Here, we present a systematic spectral pattern-based approach for the discovery of diagnostic ions, and new fragmentation mechanisms in shotgun proteomics datasets...

  16. Single Stellar Populations in the Near-Infrared - I. Preparation of the IRTF spectral stellar library

    CERN Document Server

    Meneses-Goytia, S; Trager, S C; Falcon-Barroso, J; Koleva, M; Vazdekis, A

    2015-01-01

    We present a detailed study of the stars of the IRTF spectral library to understand its full extent and reliability for use with Stellar Population (SP) modeling. The library consist of 210 stars, with a total of 292 spectra, covering the wavelength range of 0.94 to 2.41 micron at a resolution R = 2000. For every star we infer the effective temperature (Teff), gravity (logg) and metallicity ([Z/Zsun]) using a full-spectrum fitting approach in a section of the K band (2.19 to 2.34 micron) and temperature-NIR colour relations. We test the flux calibration of these stars by calculating their integrated colours and comparing them with the Pickles library colour-temperature relations. We also investigate the NIR colours as a function of the calculated effective temperature and compared them in colour-colour diagrams with the Pickles library. This latter test shows a good broad-band flux calibration, important for the SP models. Finally, we measure the resolution R as a function of wavelength. We find that the reso...

  17. The Soil Spectroscopy Group and the development of a global soil spectral library

    Science.gov (United States)

    Rossel, R. Viscarra Rossel; Soil Spectroscopy Group

    2009-04-01

    This collaboration aims to develop a global soil spectral library and to establish a community of practice for soil spectroscopy. This will help progress soil spectroscopy from an almost purely research tool to a more widely adopted and useful technique for soil analysis, proximal soil sensing, soil monitoring and digital soil mapping. The initiative started in April 2008 with a proposal for the project to be conducted in a number of stages to investigate the following topics: Global soil diversity and variation can be characterised using diffuse reflectance spectra. Soil spectral calibrations can be used to predict soil properties globally. Soil spectroscopy can be a useful tool for digital soil mapping. Currently, the soil spectral library is being developed using legacy soil organic carbon (OC) and clay content data and vis-NIR (350-2500 nm) spectra, but in future we aim to include other soil properties and mid-IR (2500-25000 nm) spectra. The group already has more than 40 collaborators from six continents and 20 countries and the library consists of 5223 spectra from 43 countries. The library accounts for spectra from approximately only 22% of the world's countries, some of which are poorly represented with only very few spectra. We would like to encourage participation from as many countries as possible, particularly, we would like contributions from counties in Central and South America, Mexico, Canada, Russia and countries in Eastern Europe, Africa and Asia. We are missing a lot of countries and for some, e.g. China we have only very few data! Do you want to join the group and contribute spectra to the global library? The requirements for contributing spectra to the global library are as follows: Spectra collected in the 350-2500 nm range every 1 nm. At least soil OC and clay content data but also any other soil chemical, physical, biological and mineralogical data, noting which analytical techniques were used. Coordinates (in WGS84 format) for each sample

  18. New H-band Stellar Spectral Libraries for the SDSS-III/APOGEE Survey

    Science.gov (United States)

    Zamora, O.; García-Hernández, D. A.; Allende Prieto, C.; Carrera, R.; Koesterke, L.; Edvardsson, B.; Castelli, F.; Plez, B.; Bizyaev, D.; Cunha, K.; García Pérez, A. E.; Gustafsson, B.; Holtzman, J. A.; Lawler, J. E.; Majewski, S. R.; Manchado, A.; Mészáros, Sz.; Shane, N.; Shetrone, M.; Smith, V. V.; Zasowski, G.

    2015-06-01

    The Sloan Digital Sky Survey-III (SDSS-III) Apache Point Observatory Galactic Evolution Experiment (APOGEE) has obtained high-resolution (R ˜ 22,500), high signal-to-noise ratio (\\gt 100) spectra in the H-band (˜1.5-1.7 μm) for about 146,000 stars in the Milky Way galaxy. We have computed spectral libraries with effective temperature ({{T}eff}) ranging from 3500 to 8000 K for the automated chemical analysis of the survey data. The libraries, used to derive stellar parameters and abundances from the APOGEE spectra in the SDSS-III data release 12 (DR12), are based on ATLAS9 model atmospheres and the ASSɛT spectral synthesis code. We present a second set of libraries based on MARCS model atmospheres and the spectral synthesis code Turbospectrum. The ATLAS9/ASSɛT ({{T}eff} = 3500-8000 K) and MARCS/Turbospectrum ({{T}eff} = 3500-5500 K) grids cover a wide range of metallicity (-2.5 ≤slant [M/H] ≤slant +0.5 dex), surface gravity (0 ≤ log g ≤slant 5 dex), microturbulence (0.5 ≤slant ξ ≤slant 8 km s-1), carbon (-1 ≤slant [C/M] ≤slant +1 dex), nitrogen (-1 ≤slant [N/M] ≤slant +1 dex), and α-element (-1 ≤slant [α/M] ≤slant +1 dex) variations, having thus seven dimensions. We compare the ATLAS9/ASSɛT and MARCS/Turbospectrum libraries and apply both of them to the analysis of the observed H-band spectra of the Sun and the K2 giant Arcturus, as well as to a selected sample of well-known giant stars observed at very high resolution. The new APOGEE libraries are publicly available and can be employed for chemical studies in the H-band using other high-resolution spectrographs.

  19. Atmospheric and Fundamental Parameters of Stars in Hubble's Next Generation Spectral Library

    Science.gov (United States)

    Heap, Sally

    2010-01-01

    Hubble's Next Generation Spectral Library (NGSL) consists of R approximately 1000 spectra of 374 stars of assorted temperature, gravity, and metallicity. We are presently working to determine the atmospheric and fundamental parameters of the stars from the NGSL spectra themselves via full-spectrum fitting of model spectra to the observed (extinction-corrected) spectrum over the full wavelength range, 0.2-1.0 micron. We use two grids of model spectra for this purpose: the very low-resolution spectral grid from Castelli-Kurucz (2004), and the grid from MARCS (2008). Both the observed spectrum and the MARCS spectra are first degraded in resolution to match the very low resolution of the Castelli-Kurucz models, so that our fitting technique is the same for both model grids. We will present our preliminary results with a comparison with those from the Sloan/Segue Stellar Parameter Pipeline, ELODIE, and MILES, etc.

  20. Effect of emissivity uncertainty on surface temperature retrieval over urban areas: Investigations based on spectral libraries

    Science.gov (United States)

    Chen, Feng; Yang, Song; Su, Z.; Wang, Kai

    2016-04-01

    Land surface emissivity (LSE) is a prerequisite for retrieving land surface temperature (LST) through single channel methods. According to error model, a 0.01 (1%) uncertainty of LSE may result in a 0.5 K error in LST under a moderate condition, while an obvious error (approximately 1 K) is possible under a warmer and less humid situation. Significant emissivity variations are presented among the anthropogenic materials in three spectral libraries, which raise a critical question that whether urban LSE can be estimated accurately to meet the needs for LST retrieval. Methods widely used for urban LSE estimation are investigated, including the classification-based method, the spectral-index based method, and the linear spectral mixture model (LSMM). Results indicate that the classification-based method may not be effectively applicable for urban LSE estimation, due mainly to the insignificant relation between the short-wave multispectral reflectance and the long-wave thermal emissivity shown by the spectra. Compared with the classification-based method, the LSMM shows relatively more accurate predictions, whereas, the performance of the LSMM largely depends on the determination of endmembers. Obvious uncertainties in LSE estimation likely appear if endmembers are determined improperly. Increasing the spectra for endmembers is a practical and beneficial means for LSMM when there is not a priori knowledge, which emphasizes the necessity of building a comprehensive spectral library of urban materials. Furthermore, the LST retrieval from a single channel of Landsat 8 is more challenging as compared with the retrieval from the channels of its predecessors-Landsat 4/5/7.

  1. Combination of Multiple Spectral Libraries Improves the Current Search Methods Used to Identify Missing Proteins in the Chromosome-Centric Human Proteome Project.

    Science.gov (United States)

    Cho, Jin-Young; Lee, Hyoung-Joo; Jeong, Seul-Ki; Kim, Kwang-Youl; Kwon, Kyung-Hoon; Yoo, Jong Shin; Omenn, Gilbert S; Baker, Mark S; Hancock, William S; Paik, Young-Ki

    2015-12-01

    Approximately 2.9 billion long base-pair human reference genome sequences are known to encode some 20 000 representative proteins. However, 3000 proteins, that is, ~15% of all proteins, have no or very weak proteomic evidence and are still missing. Missing proteins may be present in rare samples in very low abundance or be only temporarily expressed, causing problems in their detection and protein profiling. In particular, some technical limitations cause missing proteins to remain unassigned. For example, current mass spectrometry techniques have high limits and error rates for the detection of complex biological samples. An insufficient proteome coverage in a reference sequence database and spectral library also raises major issues. Thus, the development of a better strategy that results in greater sensitivity and accuracy in the search for missing proteins is necessary. To this end, we used a new strategy, which combines a reference spectral library search and a simulated spectral library search, to identify missing proteins. We built the human iRefSPL, which contains the original human reference spectral library and additional peptide sequence-spectrum match entries from other species. We also constructed the human simSPL, which contains the simulated spectra of 173 907 human tryptic peptides determined by MassAnalyzer (version 2.3.1). To prove the enhanced analytical performance of the combination of the human iRefSPL and simSPL methods for the identification of missing proteins, we attempted to reanalyze the placental tissue data set (PXD000754). The data from each experiment were analyzed using PeptideProphet, and the results were combined using iProphet. For the quality control, we applied the class-specific false-discovery rate filtering method. All of the results were filtered at a false-discovery rate of libraries, iRefSPL and simSPL, were designed to ensure no overlap of the proteome coverage. They were shown to be complementary to spectral library

  2. Determination of elemental composition of volatile organic compounds from Chinese rose oil by spectral accuracy and mass accuracy.

    Science.gov (United States)

    Zhou, Wei; Zhang, Yaheng; Xu, Hongliang; Gu, Ming

    2011-10-30

    Elemental composition determination of volatile organic compounds through high mass accuracy and isotope pattern matching could not be routinely achieved with a unit-mass resolution mass spectrometer until the recent development of the comprehensive instrument line-shape calibration technology. Through this unique technology, both m/z values and mass spectral peak shapes are calibrated simultaneously. Of fundamental importance is that calibrated mass spectra have symmetric and mathematically known peak shapes, which makes it possible to deconvolute overlapped monoisotopes and their (13)C-isotope peaks and achieve accurate mass measurements. The key experimental requirements for the measurements are to acquire true raw data in a profile or continuum mode with the acquisition threshold set to zero. A total of 13 ions from Chinese rose oil were analyzed with internal calibration. Most of the ions produced high mass accuracy of better than 5 mDa and high spectral accuracy of better than 99%. These results allow five tested ions to be identified with unique elemental compositions and the other eight ions to be determined as a top match from multiple candidates based on spectral accuracy. One of them, a coeluted component (Nerol) with m/z 154, could not be identified by conventional GC/MS (gas chromatography/mass spectrometry) and library search. Such effective determination for elemental compositions of the volatile organic compounds with a unit-mass resolution quadrupole system is obviously attributed to the significant improvement of mass accuracy. More importantly, high spectral accuracy available through the instrument line-shape calibration enables highly accurate isotope pattern recognition for unknown identification.

  3. Study on Mass Conservation Techniques for Treatment of Library and Archives Material.

    Science.gov (United States)

    Wachter, Wolfgang, Ed.

    This document outlines the present state of development in mass restoration of library and archive materials and relates it to the economic, technical, and aesthetic aspects of various conservation and restoration methods, and discusses their implications for the formation of preservation policies in libraries. Ill effects to library materials…

  4. A Web-Interface for Data Interoperability: the Spectral Library of Mt Etna Volcanic Surfaces

    Science.gov (United States)

    Colini, L.; Doumaz, F.; Spinetti, C.; Mazzarini, F.; Favalli, M.; Isola, I.; Buongiorno, M. F.; Ananasso, C.

    2014-12-01

    In the frame of the future Italian Space Agency (ASI) Space Mission PRISMA (Precursore IperSpettrale della Missione Applicativa), the Istituto Nazionale di Geofisica e Vulcanologia (INGV) coordinates the scientific project ASI-AGI (Analisi Sistemi Iperspettrali per le Applicazioni Geofisiche Integrate) aimed to study the hyperspectral volcanic applications and to identify and characterize a vicarious validation and calibration site for hyperspectral space missions. PRISMA is an Earth observation system with innovative electro-optical instrumentation which combines an hyperspectral sensor with a panchromatic medium-resolution camera. These instruments offer the scientific community and users many applications in the field of environmental monitoring, risk management, crop classification, pollution control, and Security. In this context Mt. Etna (Italy) has been choose as main site for testing the sensor capability to assess volcanic risk. The volcanic calibration and validation activities comprise the managing of a large amount of in situ hyperspectral data collected during the last 10 years. The usability and interoperability of these datasets represents a task of ASI-AGI project. For this purpose a database has been created to collect all the spectral signatures of the measured volcanic surfaces. This process has begun with the creation of the metadata structure compliant with those belonging to some standard spectral libraries such as USGS ones. Each spectral signature is described in a table containing ancillary data such as the location map of where it was collected, description of the target selected, etc. The relational database structure has been developed WOVOdat compliant. Specific tables have been formatted for each type of measurements, instruments and targets in order to query the database through a user-friendly web-interface. The interface has an upload area to populate the database and a visualization tool that allows downloading the ASCII spectral

  5. The US Geological Survey, digital spectral reflectance library: version 1: 0.2 to 3.0 microns

    Science.gov (United States)

    Clark, Roger N.; Swayze, Gregg A.; King, Trude V. V.; Gallagher, Andrea J.; Calvin, Wendy M.

    1993-01-01

    We have developed a digital reflectance spectral library, with management and spectral analysis software. The library includes 500 spectra of 447 samples (some samples include a series of grain sizes) measured from approximately 0.2 to 3.0 microns. The spectral resolution (Full Width Half Maximum) of the reflectance data is less than or equal to 4 nm in the visible (0.2-0.8 microns) and less than or equal 10 nm in the NIR (0.8-2.35 microns). All spectra were corrected to absolute reflectance using an NBS Halon standard. Library management software lets users search on parameters (e.g. chemical formulae, chemical analyses, purity of samples, mineral groups, etc.) as well as spectral features. Minerals from sulfide, oxide, hydroxide, halide, carbonate, nitrate, borate, phosphate, and silicate groups are represented. X-ray and chemical analyses are tabulated for many of the entries, and all samples have been evaluated for spectral purity. The library also contains end and intermediate members for the olivine, garnet, scapolite, montmorillonite, muscovite, jarosite, and alunite solid-solution series. We have included representative spectra of H2O ice, kerogen, ammonium-bearing minerals, rare-earth oxides, desert varnish coatings, kaolinite crystallinity series, kaolinite-smectite series, zeolite series, and an extensive evaporite series. Because of the importance of vegetation to climate-change studies we have include 17 spectra of tree leaves, bushes, and grasses.

  6. Martian Analogue Sample Characterization and Spectral Library Development at the Johnson Space Center

    Science.gov (United States)

    Morris, Richard V.

    2002-01-01

    An extensive collection of Martian analogue samples housed at the Johnson Space Center is the focus of ongoing research by the JSC Mars soil genesis group and their collaborators. Because the major element composition of Martian meteorites and in situ analyses of Martian soils and rocks indicate that Mars is predominantly an iron-rich basaltic world, the focus of active sample collection and analysis is basaltic materials and their hydrolytic (both aqueous and hydrothermal) and sulfatetic alteration products. Described below are the scope of the JSC Mars analogue sample collection, the characterization process, and plans to incorporate the data into spectral libraries for the Mars 2003 Mars Exploration Rover (MER) and Mars 2005 Mars Reconnaissance Orbiter (MRO) CRISM missions.

  7. SWATH Mass Spectrometry Performance Using Extended Peptide MS/MS Assay Libraries.

    Science.gov (United States)

    Wu, Jemma X; Song, Xiaomin; Pascovici, Dana; Zaw, Thiri; Care, Natasha; Krisp, Christoph; Molloy, Mark P

    2016-07-01

    The use of data-independent acquisition methods such as SWATH for mass spectrometry based proteomics is usually performed with peptide MS/MS assay libraries which enable identification and quantitation of peptide peak areas. Reference assay libraries can be generated locally through information dependent acquisition, or obtained from community data repositories for commonly studied organisms. However, there have been no studies performed to systematically evaluate how locally generated or repository-based assay libraries affect SWATH performance for proteomic studies. To undertake this analysis, we developed a software workflow, SwathXtend, which generates extended peptide assay libraries by integration with a local seed library and delivers statistical analysis of SWATH-quantitative comparisons. We designed test samples using peptides from a yeast extract spiked into peptides from human K562 cell lysates at three different ratios to simulate protein abundance change comparisons. SWATH-MS performance was assessed using local and external assay libraries of varying complexities and proteome compositions. These experiments demonstrated that local seed libraries integrated with external assay libraries achieve better performance than local assay libraries alone, in terms of the number of identified peptides and proteins and the specificity to detect differentially abundant proteins. Our findings show that the performance of extended assay libraries is influenced by the MS/MS feature similarity of the seed and external libraries, while statistical analysis using multiple testing corrections increases the statistical rigor needed when searching against large extended assay libraries.

  8. [Non-target screening of organic pollutants in sediments and sludges using gas chromatography-mass spectrometry and automated mass spectral deconvolution].

    Science.gov (United States)

    Wang, Gang; Ma, Huilian; Wang, Longxing; Chen, Jiping; Hou, Xiaohong

    2015-12-01

    A screening method in the combination of ultrasonic extraction, gas chromatography-mass spectrometry detection and automated mass spectrometry deconvolution technique was developed for non-target screening of non-polar and weak polar pollutants in sediments and sludges. The samples were extracted by ultrasonication for 20 min using dichloromethane for three times. The extraction solutions were cleaned-up by gel permeation chromatography and a silica gel column, and then 3 g of copper powder was used to remove the sulfur by ultrasonication for 10 min. Parallel experiments were carried out for 5 times and the RSDs were ranged from 5.8% to 14.9%. Automated mass spectral deconvolution & identification system (AMDIS) would improve the resolution of overlapping peaks, and identify the pure mass spectrum of the analytes in the cases of stronger background interference and co-extracted substances covering. Standard spectrum databases, such as NISTDRUG, NISTEPA, NISTFDA, Mass Spectral Library, etc, would qualitatively identify the organic pollutants in the samples. As a result, a total of 290 organic pollutants were identified, of which 190 and 153 pollutants were found in sediments and sludges, respectively. The identified pollutants included the Environmental Protection Agency (EPA) priority pollutants, pharmaceuticals, herbicides, antioxidants, intermediates, organic solvents and chemical raw materials. The proposed method is proved to be a promising one for non-target screening of complex matrix samples with the advantages of higher sensitivity and better repeatability.

  9. Mass Digitisation by Libraries: Issues concerning Organisation, Quality and Efficiency

    Directory of Open Access Journals (Sweden)

    Astrid Verheusen

    2008-03-01

    Full Text Available Ever since the world-wide web made it possible to display graphics on the Internet, libraries have been scanning their older documents and pictures to provide access to them. From the middle of the 1990s thousands of libraries of all sizes began scanning parts of their collections, provided these with metadata and made them available on the web. The emphasis in these first, rather small, digitisation projects was on experimenting with different techniques for both scanning and building interfaces for the Internet. Along the way, methods for quality assurance, project management and business models became more professional. In line with the progress made in the field of digitisation, a profound knowledge of best practices has been developed. However, this knowledge is not available for all cultural heritage institutions who want to digitise their collections. Most of the smaller institutions lack experience and, moreover, the means to digitise in an efficient way. At the same time, the larger libraries are moving towards large-scale digitisation of historical texts while Google has already digitised millions of books from several libraries around the world. Although many libraries welcome the unprecedented access to all this information, Google has also been criticized for the inferior quality of their images, the emphasis on the English language, the violation of copyright laws and the lack of attention for preservation issues. The question therefore arises: can libraries do better than Google?

  10. Evaluating Field Spectrometer Performance with Transmission Standards: Examples from the USGS Spectral Library and Research Databases

    Science.gov (United States)

    Hoefen, T. M.; Kokaly, R. F.; Swayze, G. A.; Livo, K. E.

    2015-12-01

    Collection of spectroscopic data has expanded with the development of field-portable spectrometers. The most commonly available spectrometers span one or several wavelength ranges: the visible (VIS) and near-infrared (NIR) region from approximately 400 to 1000 nm, and the shortwave infrared (SWIR) region from approximately 1000-2500 nm. Basic characteristics of spectrometer performance are the wavelength position and bandpass of each channel. Bandpass can vary across the wavelength coverage of an instrument, due to spectrometer design and detector materials. Spectrometer specifications can differ from one instrument to the next for a given model and between manufacturers. The USGS Spectroscopy Lab in Denver has developed a simple method to evaluate field spectrometer wavelength accuracy and bandpass values using transmission measurements of materials with intense, narrow absorption features, including Mylar* plastic, praseodymium-doped glass, and National Institute of Standards and Technology Standard Reference Material 2035. The evaluation procedure has been applied in laboratory and field settings for 19 years and used to detect deviations from cited manufacturer specifications. Tracking of USGS spectrometers with transmission standards has revealed several instances of wavelength shifts due to wear in spectrometer components. Since shifts in channel wavelengths and differences in bandpass between instruments can impact the use of field spectrometer data to calibrate and analyze imaging spectrometer data, field protocols to measure wavelength standards can limit data loss due to spectrometer degradation. In this paper, the evaluation procedure will be described and examples of observed wavelength shifts during a spectrometer field season will be presented. The impact of changing wavelength and bandpass characteristics on spectral measurements will be demonstrated and implications for spectral libraries will be discussed. *Any use of trade, firm, or product names

  11. Implementation of an FTIR spectral library of 486 filamentous fungi strains for rapid identification of molds.

    Science.gov (United States)

    Lecellier, A; Gaydou, V; Mounier, J; Hermet, A; Castrec, L; Barbier, G; Ablain, W; Manfait, M; Toubas, D; Sockalingum, G D

    2015-02-01

    Filamentous fungi may cause food and feed spoilage and produce harmful metabolites to human and animal health such as mycotoxins. Identification of fungi using conventional phenotypic methods is time-consuming and molecular methods are still quite expensive and require specific laboratory skills. In the last two decades, it has been shown that Fourier transform infrared (FTIR) spectroscopy was an efficient tool for microorganism identification. The aims of this study were to use a simple protocol for the identification of filamentous fungi using FTIR spectroscopy coupled with a partial least squares discriminant analysis (PLS-DA), to implement a procedure to validate the obtained results, and to assess the transferability of the method and database. FTIR spectra of 486 strains (43 genera and 140 species) were recorded. An IR spectral database built with 288 strains was used to identify 105 different strains. It was found that 99.17% and 92.3% of spectra derived from these strains were correctly assigned at the genus and species levels, respectively. The establishment of a score and a threshold permitted to validate 80.79% of the results obtained. A standardization function (SF) was also implemented and tested on FTIR data from another instrument on a different site and permitted to increase the percentage of well predicted spectra for this set from 72.15% to 89.13%. This study confirms the good performance of high throughput FTIR spectroscopy for fungal identification using a spectral library of molds of industrial relevance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. The Advanced Spectral Library (ASTRAL): Abundance Analysis of the CP Star HR 465

    Science.gov (United States)

    Carpenter, Kenneth G.; Nielsen, Krister E.; Kober, Gladys V.

    2016-01-01

    We present the results of a spectrum analysis of the prototypical A-type magnetic CP star HR465. Synthetic spectra, using an non-LTE atmosphere model, were generated to fit high-resolution ultraviolet spectra (1200-3100 A) obtained as a part of the "Advanced Spectral Library (ASTRAL) Project: Hot Stars" program (GO-13346: Ayres PI). The ultraviolet data were supplemented by high resolution optical data recorded at the Nordic Optical Telescope with the SOFIN spectrograph. The optical data was used as a complement to the high line density ultraviolet spectrum and primarily used to derive accurate iron-group element abundances.HR 465 has previously been analyzed using IUE spectra. We revisit the object with this high quality data. Large parts of the spectrum have been synthesized with an ATLAS model (Teff=10750K, logg=4.0) and we present abundance results for more than 50 elements. We can confirm some of the abundance characteristics previously derived from IUE data, where elements heavier than Z=30 show significant abundance enhancements compared to solar values, while some of the lighter elements show abundance deficiencies. We will place these results in context of other AP stars, and the large number of element abundances will also help us to put some constraint on stellar abundance and evolution theories.

  13. Testing an alternative search algorithm for compound identification with the 'Wiley Registry of Tandem Mass Spectral Data, MSforID'.

    Science.gov (United States)

    Oberacher, Herbert; Whitley, Graeme; Berger, Bernd; Weinmann, Wolfgang

    2013-04-01

    A tandem mass spectral database system consists of a library of reference spectra and a search program. State-of-the-art search programs show a high tolerance for variability in compound-specific fragmentation patterns produced by collision-induced decomposition and enable sensitive and specific 'identity search'. In this communication, performance characteristics of two search algorithms combined with the 'Wiley Registry of Tandem Mass Spectral Data, MSforID' (Wiley Registry MSMS, John Wiley and Sons, Hoboken, NJ, USA) were evaluated. The search algorithms tested were the MSMS search algorithm implemented in the NIST MS Search program 2.0g (NIST, Gaithersburg, MD, USA) and the MSforID algorithm (John Wiley and Sons, Hoboken, NJ, USA). Sample spectra were acquired on different instruments and, thus, covered a broad range of possible experimental conditions or were generated in silico. For each algorithm, more than 30,000 matches were performed. Statistical evaluation of the library search results revealed that principally both search algorithms can be combined with the Wiley Registry MSMS to create a reliable identification tool. It appears, however, that a higher degree of spectral similarity is necessary to obtain a correct match with the NIST MS Search program. This characteristic of the NIST MS Search program has a positive effect on specificity as it helps to avoid false positive matches (type I errors), but reduces sensitivity. Thus, particularly with sample spectra acquired on instruments differing in their setup from tandem-in-space type fragmentation, a comparably higher number of false negative matches (type II errors) were observed by searching the Wiley Registry MSMS.

  14. Decoding Split and Pool Combinatorial Libraries with Electron-Transfer Dissociation Tandem Mass Spectrometry

    Science.gov (United States)

    Sarkar, Mohosin; Pascal, Bruce D.; Steckler, Caitlin; Aquino, Claudio; Micalizio, Glenn C.; Kodadek, Thomas; Chalmers, Michael J.

    2013-07-01

    Screening of bead-based split and pool combinatorial chemistry libraries is a powerful approach to aid the discovery of new chemical compounds able to interact with, and modulate the activities of, protein targets of interest. Split and pool synthesis provides for large and well diversified chemical libraries, in this case comprised of oligomers generated from a well-defined starting set. At the end of the synthesis, each bead in the library displays many copies of a unique oligomer sequence. Because the sequence of the oligomer is not known at the time of screening, methods for decoding of the sequence of each screening "hit" are essential. Here we describe an electron-transfer dissociation (ETD) based tandem mass spectrometry approach for the decoding of mass-encoded split and pool libraries. We demonstrate that the newly described "chiral oligomers of pentenoic amides (COPAs)" yield non-sequence-specific product ions upon collisional activated dissociation; however, complete sequence information can be obtained with ETD. To aid in the decoding of libraries from MS and MS/MS data, we have incorporated 79Br/81Br isotope "tags" to differentiate N- and C-terminal product ions. In addition, we have created "Hit-Find," a software program that allows users to generate libraries in silico . The user can then search all possible members of the chemical library for those that fall within a user-defined mass error.

  15. Spectral diffusion and drift: single chromophore and en masse.

    Science.gov (United States)

    Lubchenko, Vassiliy; Silbey, Robert J

    2007-02-14

    We develop a systematic description of spectral diffusion of ideal chromophores interacting with incoherently relaxing two-state, localized environmental degrees of freedom ("spins") for general initial environment configurations. We remedy the existing, incomplete treatments by formulating the problem in terms of the proper correlation function and by obtaining an accurate solution for generic aperiodic arrangements of environmental spins, nearly free of the customary simplifying assumptions on the multiparticle spin coordinate distribution. We report and estimate, for the first time, the effects of the drift and distortion of a narrow spectral line that arise when the line is not in the center of the inhomogeneous band. While the drift turns out to be modest in most ensemble measurements, accounting for its effects is imperative in analyzing single chromophore spectral jumps, to which end the authors propose a novel experiment. Further, we argue that by employing a sufficiently large chromophore one can decouple the concentration of the fluctuating centers from the strength of their interaction with the chromophore. Finally, the additional line broadening, owing to a distribution of the central chromophore frequencies, is evaluated. Upper estimates for an analogous broadening stemming from a nonequilibrium environment are made.

  16. Combinatorial Library Screening Coupled to Mass Spectrometry to Identify Valuable Cyclic Peptides.

    Science.gov (United States)

    Camperi, Silvia A; Giudicessi, Silvana L; Martínez-Ceron, María C; Gurevich-Messina, Juan M; Saavedra, Soledad L; Acosta, Gerardo; Cascone, Osvaldo; Erra-Balsells, Rosa; Albericio, Fernando

    2016-06-02

    Combinatorial library screening coupled to mass spectrometry (MS) analysis is a practical approach to identify useful peptides. Cyclic peptides can have high biological activity, selectivity, and affinity for target proteins, and high stability against proteolytic degradation. Here we describe two strategies to prepare combinatorial libraries suitable for MS analysis to accelerate the discovery of cyclic peptide structures. Both approaches use ChemMatrix resin and the linker 4-hydroxymethylbenzoic acid. One strategy involves the synthesis of a one-bead-two-peptides library in which each bead contains both the cyclic peptide and its linear counterpart to facilitate MS analysis. The other protocol is based on the synthesis of a cyclic depsipeptide library in which a glycolamidic ester group is incorporated by adding glycolic acid. After library screening, the ring is opened and the peptide is released simultaneously for subsequent MS analysis. © 2016 by John Wiley & Sons, Inc.

  17. Mass anomalous dimension of SU(2) using the spectral density method

    CERN Document Server

    Suorsa, Joni M; Rantaharju, Jarno; Rantalaiho, Teemu; Rummukainen, Kari; Tuominen, Kimmo; Tähtinen, Sara

    2016-01-01

    SU(2) with N_f = 6 and N_f = 8 are believed to have an infrared conformal fixed point. We use the spectral density method cross referenced with the mass step scaling method to evaluate the coupling constant dependence of the mass anomalous dimension for massless HEX smeared, clover improved Wilson fermions with Schr\\"odinger functional boundary conditions.

  18. Metabolite Identification Using Automated Comparison of High-Resolution Multistage Mass Spectral Trees

    NARCIS (Netherlands)

    Rojas-Cherto, M.; Peironcely, J.E.; Kasper, P.T.; Hooft, van der J.J.J.; Vos, de R.C.H.; Vreeken, R.; Hankemeier, T.; Reijmers, T.

    2012-01-01

    Multistage mass spectrometry (MSn) generating so-called spectral trees is a powerful tool in the annotation and structural elucidation of metabolites and is increasingly used in the area of accurate mass LC/MS-based metabolomics to identify unknown, but biologically relevant, compounds. As a consequ

  19. A Complete Library of Infrared Spectral Energy Distributions for z=0 Galaxies

    Science.gov (United States)

    Sandstrom, Karin

    CONTEXT: Half of the light emitted by galaxies is starlight absorbed and reprocessed into the infrared by dust. The spectral energy distribution (SED) of this IR emission encodes information on the mass and properties of the dust, the radiation field heating it, and the bolometric luminosity of the region. This makes IR emission a main tool to estimate star formation rates (SFRs) and to trace the distribution of the interstellar medium (ISM) in galaxies. The dust itself also plays key roles in the physics of star formation, and thereby galaxy evolution. This critical information on dust and its dependence on environment can only be reliably measured when we have observations with full wavelength coverage of the IR SED that resolve galaxies. With no new IR imaging missions on the horizon, the remarkably thorough census conducted by Herschel, Spitzer, and WISE of the nearby (D formation rate? (2) How are dust and gas related across the galaxy population and how can dust emission best be used to trace gas? and (3) How does the dust grain population vary in response to local environment across galaxies? METHODS: We will use established techniques to uniformly process the archival data, fit models to the spectral energy distributions, match the data in resolution. These have been successfully deployed on similar data by individual teams (including us), but we will apply them to an order of magnitude larger sample. PERCEIVED SIGNIFICANCE: Dust is a main mediator of cloud and star formation, and thus galaxy evolution. Therefore, the properties and evolution of dust in galaxies is directly relevant to key NASA science goals to "Discover how the universe works, explore how it began and evolved, and search for life on planets around other stars." These are also essential tools to understand "How did we get here?" In practical terms, the database that we propose to create would be a major resource for many scientists: a tool to understand the physics of dust and the ISM for

  20. Mass spectral peak distortion due to Fourier transform signal processing.

    Science.gov (United States)

    Rockwood, Alan L; Erve, John C L

    2014-12-01

    Distortions of peaks can occur when one uses the standard method of signal processing of data from the Orbitrap and other FT-based methods of mass spectrometry. These distortions arise because the standard method of signal processing is not a linear process. If one adds two or more functions, such as time-dependent signals from a Fourier transform mass spectrometer and performs a linear operation on the sum, the result is the same as if the operation was performed on separate functions and the results added. If this relationship is not valid, the operation is non-linear and can produce unexpected and/or distorted results. Although the Fourier transform itself is a linear operator, the standard algorithm for processing spectra in Fourier transform-based methods include non-linear mathematical operators such that spectra processed by the standard algorithm may become distorted. The most serious consequence is that apparent abundances of the peaks in the spectrum may be incorrect. In light of these considerations, we performed theoretical modeling studies to illustrate several distortion effects that can be observed, including abundance distortions. In addition, we discuss experimental systems where these effects may manifest, including suggested systems for study that should demonstrate these peak distortions. Finally, we point to several examples in the literature where peak distortions may be rationalized by the phenomena presented here.

  1. Towards a Standard Plant Species Spectral Library Protocol for Vegetation Mapping: A Case Study in the Shrubland of Doñana National Park

    Directory of Open Access Journals (Sweden)

    Marcos Jiménez

    2015-11-01

    Full Text Available One of the main applications of field spectroscopy is the generation of spectral libraries of Earth’s surfaces or materials to support mapping activities using imaging spectroscopy. To enhance the reliability of these libraries, spectral signature acquisition should be carried out following standard procedures and controlled experimental approaches. This paper presents a standard protocol for the creation of a spectral library for plant species. The protocol is based on characterizing the reflectance spectral response of different species in the spatiotemporal domain, by accounting for intra-species variation and inter-species similarity. A practical case study was conducted on the shrubland located in Doñana National Park (SW Spain. Spectral libraries of the five dominant shrub species were built (Erica scoparia, Halimium halimifolium, Ulex australis, Rosmarinus officinalis, and Stauracanthus genistoides. An estimation was made of the separability between species: on one hand, the Student’s t-test evaluates significant intra-species variability (p < 0.05 and on the other hand, spectral similarity value (SSV and spectral angle mapper (SAM algorithms obtain significant separability values for dominant species, although it was not possible to discriminate the legume species Ulex australis and Stauracanthus genistoides.

  2. Design and Development of a Spectral Library for Different Vegetation and Landcover Types for Arctic, Antarctic and Chihuahua Desert Ecosystem

    Science.gov (United States)

    Matharasi, K.; Goswami, S.; Gamon, J.; Vargas, S.; Marin, R.; Lin, D.; Tweedie, C. E.

    2008-12-01

    All objects on the Earth's surface absorb and reflect portions of the electromagnetic spectrum. Depending on the composition of the material, every material has its characteristic spectral profile. The characteristic spectral profile for vegetation is often used to study how vegetation patterns at large spatial scales affect ecosystem structure and function. Analysis of spectroscopic data from the laboratory, and from various other platforms like aircraft or spacecraft, requires a knowledge base that consists of different characteristic spectral profiles for known different materials. This study reports on establishment of an online and searchable spectral library for a range of plant species and landcover types in the Arctic, Anatarctic and Chihuahuan desert ecosystems. Field data were collected from Arctic Alaska, the Antarctic Peninsula and the Chihuahuan desert in the visible to near infrared (IR) range using a handheld portable spectrometer. The data have been archived in a database created using postgre sql with have been made publicly available on a plone web-interface. This poster describes the data collected in more detail and offers instruction to users who wish to make use of this free online resource.

  3. Mass Spectral Molecular Networking of Living Microbial Colonies

    Energy Technology Data Exchange (ETDEWEB)

    Watrous, Jeramie D.; Roach, Patrick J.; Alexandrov, Theodore; Heath, Brandi S.; Yang, Jane Y.; Kersten, Roland; vander Voort, Menno; Pogliano, Kit; Gross, Harald; Raaijmakers, Jos M.; Moore, Bradley S.; Laskin, Julia; Bandeira, Nuno; Dorrestein, Pieter C.

    2012-06-26

    Integrating the governing chemistry with the genomics and phenotypes of microbial colonies has been a "holy grail" in microbiology. This work describes a highly sensitive, broadly applicable, and costeffective approach that allows metabolic profiling of live microbial colonies directly from a Petri dish without any sample preparation. Nanospray desorption electrospray ionization mass spectrometry (MS), combined with alignment of MS data and molecular networking, enabled monitoring of metabolite production from live microbial colonies from diverse bacterial genera, including Bacillus subtilis, Streptomyces coelicolor, Mycobacterium smegmatis, and Pseudomonas aeruginosa. This work demonstrates that, by using these tools to visualize small molecular changes within bacterial interactions, insights can be gained into bacterial developmental processes as a result of the improved organization of MS/MS data. To validate this experimental platform, metabolic profiling was performed on Pseudomonas sp. SH-C52, which protects sugar beet plants from infections by specific soil-borne fungi [R. Mendes et al. (2011) Science 332:1097–1100]. The antifungal effect of strain SHC52 was attributed to thanamycin, a predicted lipopeptide encoded by a nonribosomal peptide synthetase gene cluster. Our technology, in combination with our recently developed peptidogenomics strategy, enabled the detection and partial characterization of thanamycin and showed that it is amonochlorinated lipopeptide that belongs to the syringomycin family of antifungal agents. In conclusion, the platform presented here provides a significant advancement in our ability to understand the spatiotemporal dynamics of metabolite production in live microbial colonies and communities.

  4. Mass anomalous dimension of SU(2) with Nf=8 using the spectral density method

    DEFF Research Database (Denmark)

    Suorsa, Joni M.; Leino, Viljami; Rantaharju, Jarno

    2015-01-01

    SU(2) with Nf=8 is believed to have an infrared conformal fixed point. We use the spectral density method to evaluate the coupling constant dependence of the mass anomalous dimension for massless HEX smeared, clover improved Wilson fermions with Schr\\"odinger functional boundary conditions....

  5. A spectral-unmixing approach to estimate water-mass concentrations in case 2 waters

    NARCIS (Netherlands)

    Burazerovic, D.; Heylen, R.; Raymaekers, D.; Knaeps, E.; Philippart, C.J.M.; Scheunders, P.

    2014-01-01

    In this work, we study the estimation of water-quality parameters from the water-leaving reflectance by means of spectral unmixing. Our starting point is the provision of an analytic model relating the reflectance of water to its masses/bodies or constituents, as specified by their specific inherent

  6. Mass spectral analysis of C3 and C4 aliphatic amino acid derivatives.

    Science.gov (United States)

    Lawless, J. G.; Chadha, M. S.

    1971-01-01

    Diagnostic criteria are obtained for the distinction of alpha, beta, gamma, and N-methyl isomers of the C3 and C4 aliphatic amino acids, using mass spectral analysis of the derivatives of these acids. The use of deuterium labeling has helped in the understanding of certain fragmentation pathways.

  7. Mass anomalous dimension of SU(2) with Nf=8 using the spectral density method

    CERN Document Server

    Suorsa, Joni M; Rantaharju, Jarno; Rantalaiho, Teemu; Rummukainen, Kari; Tuominen, Kimmo; Weir, David J

    2015-01-01

    SU(2) with Nf=8 is believed to have an infrared conformal fixed point. We use the spectral density method to evaluate the coupling constant dependence of the mass anomalous dimension for massless HEX smeared, clover improved Wilson fermions with Schr\\"odinger functional boundary conditions.

  8. Fast atom bombardment (FAB) mass spectrometry: a mass spectral investigation of some of the insulins.

    Science.gov (United States)

    Barber, M; Bordoli, R S; Elliott, G J; Tyler, A N; Bill, J C; Green, B N

    1984-04-01

    Mass measurements of the protonated molecules [M + H]+ of four insulins are presented. In addition, structurally significant fragment ions are observed in the mass spectrum and metastable scanning has been used to link these ions to the protonated molecule.

  9. A Digital Low Dispersion Spectral Library Covering the 3500-7500 Å Region Using the SAAO Radcliffe 1.9 m Telescope's Cassegrain Spectrograph

    Science.gov (United States)

    James, David J.

    2013-09-01

    We have created a digital spectral library, using low resolution optical spectra, of photometric and spectral standard stars. The data were acquired using the Cassegrain spectrograph installed on the 1.9 m Radcliffe telescope at the South African Astronomical Observatory. The library consists of optical wavelength (sime3500-7500 Å) spectra for main sequence and giant stars encompassing those most commonly observed in the Galaxy, namely the late-B, A, F, G, K, and early- to mid-M stars. We intend that our standard star spectra will be especially useful for spectral classification of stars in the field and Galactic clusters alike and will have high pedagogic value when included into representative "Introductory Astronomy" or "Stellar Astronomy" curricula for undergraduate astronomy major and minor programs. We exploit the spectral library in order to derive spectral types for 76 optically and X-ray selected members of the young open cluster NGC 6475. Comparison of spectral type, optical and infrared photometric data to theoretical colors derived from spectral type show that the reddening of the cluster is EBV = 0.068 ± 0.012 (1σ = 0.058), a vector consistent with earlier surveys. Our analysis also highlights the utility of such spectra in rejecting cluster nonmembers, thereby allowing the creation of a clean sample of bona fide cluster members for follow-up science observations.

  10. Parametric Power Spectral Density Analysis of Noise from Instrumentation in MALDI TOF Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    John M. Koomen

    2007-01-01

    Full Text Available Noise in mass spectrometry can interfere with identification of the biochemical substances in the sample. For example, the electric motors and circuits inside the mass spectrometer or in nearby equipment generate random noise that may distort the true shape of mass spectra. This paper presents a stochastic signal processing approach to analyzing noise from electrical noise sources (i.e., noise from instrumentation in MALDI TOF mass spectrometry. Noise from instrumentation was hypothesized to be a mixture of thermal noise, 1/f noise, and electric or magnetic interference in the instrument. Parametric power spectral density estimation was conducted to derive the power distribution of noise from instrumentation with respect to frequencies. As expected, the experimental results show that noise from instrumentation contains 1/f noise and prominent periodic components in addition to thermal noise. These periodic components imply that the mass spectrometers used in this study may not be completely shielded from the internal or external electrical noise sources. However, according to a simulation study of human plasma mass spectra, noise from instrumentation does not seem to affect mass spectra significantly. In conclusion, analysis of noise from instrumentation using stochastic signal processing here provides an intuitive perspective on how to quantify noise in mass spectrometry through spectral modeling.

  11. Screening Non-colored Phenolics in Red Wines using Liquid Chromatography/Ultraviolet and Mass Spectrometry/Mass Spectrometry Libraries

    Directory of Open Access Journals (Sweden)

    Changqing Duan

    2007-03-01

    Full Text Available Liquid chromatography/ultraviolet (LC/UV and mass spectrometry/mass spectrometry (MS/MS libraries containing 39 phenolic compounds were established by coupling a LC and an ion trap MS with an electrospray ionization (ESI source, operated in negative ion mode. As a result, the deprotonated [M-H]- molecule was observed for all the analyzed compounds. Using MS/MS hydroxybenzoic acid and hydroxycinnamic acids showed a loss of CO2 and production of a [M-H-44] - fragment and as expected, the UV spectra of these two compounds were affected by their chemical structures. For flavonol and flavonol glycosides, the spectra of their glycosides and aglycones produced deprotonated [M-H]- and [A-H]- species, respectively, and their UV spectra each presented two major absorption peaks. The UV spectra and MS/MS data of flavan-3-ols and stilbenes were also investigated. Using the optimized LC/MS/MS analytical conditions, the phenolic extracts from six representative wine samples were analyzed and 31 phenolic compounds were detected, 26 of which were identified by searching the LC/UV and MS/MS libraries. Finally, the presence of phenolic compounds was confirmed in different wine samples using the LC/UV and LC/MS/MS libraries.

  12. Spectral analysis of shielded gamma ray sources using precalculated library data

    Science.gov (United States)

    Holmes, Thomas Wesley; Gardner, Robin P.

    2015-11-01

    In this work, an approach has been developed for determining the intensity of a shielded source by first determining the thicknesses of three different shielding materials from a passively collected gamma-ray spectrum by making comparisons with predetermined shielded spectra. These evaluations are dependent on the accuracy and validity of the predetermined library spectra which were created by changing the thicknesses of the three chosen materials lead, aluminum and wood that are used to simulate any actual shielding. Each of the spectra produced was generated using MCNP5 with a sufficiently large number of histories to ensure a low relative error at each channel. The materials were held in the same respective order from source to detector, where each material consisted of three individual thicknesses and a null condition. This then produced two separate data sets of 27 total shielding material situations and subsequent predetermined libraries that were created for each radionuclide source used. The technique used to calculate the thicknesses of the materials implements a Levenberg-Marquardt nonlinear search that employs a tri-linear interpolation with the respective predetermined libraries within each channel for the supplied input unknown spectrum. Given that the nonlinear parameters require an initial guess for the calculations, the approach demonstrates first that when the correct values are input, the correct thicknesses are found. It then demonstrates that when multiple trials of random values are input for each of the nonlinear parameters, the average of the calculated solutions that successfully converges also produced the correct thicknesses. Under situations with sufficient information known about the detection situation at hand, the method was shown to behave in a manner that produces reasonable results and can serve as a good preliminary solution. This technique has the capability to be used in a variety of full spectrum inverse analysis problems

  13. Development of a new spectral library classifier for airborne hyperspectral images on heterogeneous environments

    OpenAIRE

    Mende, Andre; Heiden, Uta; Bachmann, Martin; Hoja, Danielle; Buchroithner, Manfred

    2011-01-01

    The classification of hyperspectral images on heterogeneous environments without prior knowledge about the study area is a challenging task. Finding potential pure spectral signatures or endmembers (EM) of the various surface materials within an image is essential for obtaining accurate classification results. Automated endmember selection techniques, in many cases, return an unlabelled result without a relationship to a known material. This study demonstrates the potential of an automated sp...

  14. Derivation of an urban materials spectral library through emittance and reflectance spectroscopy

    OpenAIRE

    Kotthaus, Simone; Smith, Thomas E. L.; Wooster, Martin J.; C. S. B. Grimmond

    2014-01-01

    Recent advances in thermal infrared remote sensing include the increased availability of airborne hyperspectral imagers (such as the Hyperspectral Thermal Emission Spectrometer, HyTES, or the Telops HyperCam and the Specim aisaOWL), and it is planned that an increased number spectral bands in the long-wave infrared (LWIR) region will soon be measured from space at reasonably high spatial resolution (by imagers such as HyspIRI). Detailed LWIR emissivity spectra are required to best interpret t...

  15. Defining and Detecting Complex Peak Relationships in Mass Spectral Data: The Mz.unity Algorithm.

    Science.gov (United States)

    Mahieu, Nathaniel G; Spalding, Jonathan L; Gelman, Susan J; Patti, Gary J

    2016-09-20

    Analysis of a single analyte by mass spectrometry can result in the detection of more than 100 degenerate peaks. These degenerate peaks complicate spectral interpretation and are challenging to annotate. In mass spectrometry-based metabolomics, this degeneracy leads to inflated false discovery rates, data sets containing an order of magnitude more features than analytes, and an inefficient use of resources during data analysis. Although software has been introduced to annotate spectral degeneracy, current approaches are unable to represent several important classes of peak relationships. These include heterodimers and higher complex adducts, distal fragments, relationships between peaks in different polarities, and complex adducts between features and background peaks. Here we outline sources of peak degeneracy in mass spectra that are not annotated by current approaches and introduce a software package called mz.unity to detect these relationships in accurate mass data. Using mz.unity, we find that data sets contain many more complex relationships than we anticipated. Examples include the adduct of glutamate and nicotinamide adenine dinucleotide (NAD), fragments of NAD detected in the same or opposite polarities, and the adduct of glutamate and a background peak. Further, the complex relationships we identify show that several assumptions commonly made when interpreting mass spectral degeneracy do not hold in general. These contributions provide new tools and insight to aid in the annotation of complex spectral relationships and provide a foundation for improved data set identification. Mz.unity is an R package and is freely available at https://github.com/nathaniel-mahieu/mz.unity as well as our laboratory Web site http://pattilab.wustl.edu/software/ .

  16. A Digital Low Dispersion Spectral Library Covering the 3500-7500AA Region Using the SAAO Radcliffe 1.9m Telescope's Cassegrain Spectrograph

    CERN Document Server

    James, David

    2013-01-01

    We have created a digital spectral library, using low resolution optical spectra, of photometric and spectral standard stars. The data were acquired using the Cassegrain Spectrograph installed on the 1.9m Radcliffe telescope at the South African Astronomical Observatory. The library consists of optical wavelength (~ 3500-7500AA) spectra for main sequence and giant stars encompassing those most commonly observed in the Galaxy, namely the late-B, A-, F-, G-, K-, and early- to mid-M stars. We intend that our standard star spectra will be especially useful for spectral classification of stars in the field and Galactic clusters alike, and will have high pedagogic value when included into representative Introductory Astronomy or Stellar Astronomy curricula for undergraduate astronomy major and minor programs. We exploit the spectral library in order to derive spectral types for seventy-six optically and X-ray selected members of the young open cluster NGC 6475. Comparison of spectral-type, optical and infrared phot...

  17. TOF plotter—a program to perform routine analysis time-of-flight mass spectral data

    Science.gov (United States)

    Knippel, Brad C.; Padgett, Clifford W.; Marcus, R. Kenneth

    2004-03-01

    The main article discusses the operation and application of the program to mass spectral data files. This laboratory has recently reported the construction and characterization of a linear time-of-flight mass spectrometer (ToF-MS) utilizing a radio frequency glow discharge ionization source. Data acquisition and analysis was performed using a digital oscilloscope and Microsoft Excel, respectively. Presently, no software package is available that is specifically designed for time-of-flight mass spectral analysis that is not instrument dependent. While spreadsheet applications such as Excel offer tremendous utility, they can be cumbersome when repeatedly performing tasks which are too complex or too user intensive for macros to be viable. To address this situation and make data analysis a faster, simpler task, our laboratory has developed a Microsoft Windows-based software program coded in Microsoft Visual Basic. This program enables the user to rapidly perform routine data analysis tasks such as mass calibration, plotting and smoothing on x- y data sets. In addition to a suite of tools for data analysis, a number of calculators are built into the software to simplify routine calculations pertaining to linear ToF-MS. These include mass resolution, ion kinetic energy and single peak identification calculators. A detailed description of the software and its associated functions is presented followed by a characterization of its performance in the analysis of several representative ToF-MS spectra obtained from different GD-ToF-MS systems.

  18. Dynamic Analysis of a Timoshenko Beam Subjected to an Accelerating Mass Using Spectral Element Method

    Directory of Open Access Journals (Sweden)

    Guangsong Chen

    2014-01-01

    Full Text Available This paper presents formulations for a Timoshenko beam subjected to an accelerating mass using spectral element method in time domain (TSEM. Vertical displacement and bending rotation of the beam were interpolated by Lagrange polynomials supported on the Gauss-Lobatto-Legendre (GLL points. By using GLL integration rule, the mass matrix was diagonal and the dynamic responses can be obtained efficiently and accurately. The results were compared with those obtained in the literature to verify the correctness. The variation of the vibration frequencies of the Timoshenko and moving mass system was researched. The effects of inertial force, centrifugal force, Coriolis force, and tangential force on a Timoshenko beam subjected to an accelerating mass were investigated.

  19. Simulations of non-equal mass black hole binaries with spectral methods

    CERN Document Server

    Buchman, Luisa T; Scheel, Mark A; Szilagyi, Bela

    2012-01-01

    This paper presents techniques and results for simulations of unequal mass, non-spinning black hole binaries with pseudo-spectral methods. Specifically, we develop an efficient root-finding procedure to ensure the black hole initial data have the desired masses and spins, we extend the dual coordinate frame method and eccentricity removal to asymmetric binaries. Furthermore, we describe techniques to simulate mergers of unequal mass black holes. The second part of the paper presents numerical simulations of non-spinning black hole binaries with mass ratios 2, 3, 4 and 6, covering between 15 and 22 orbits, merger and ringdown. We discuss the accuracy of these simulations, the evolution of the (initially zero) black hole spins, and the remnant black hole properties.

  20. In Silico Identification Software (ISIS): A Machine Learning Approach to Tandem Mass Spectral Identification of Lipids

    Energy Technology Data Exchange (ETDEWEB)

    Kangas, Lars J.; Metz, Thomas O.; Isaac, Georgis; Schrom, Brian T.; Ginovska-Pangovska, Bojana; Wang, Luning; Tan, Li; Lewis, Robert R.; Miller, John H.

    2012-05-15

    Liquid chromatography-mass spectrometry-based metabolomics has gained importance in the life sciences, yet it is not supported by software tools for high throughput identification of metabolites based on their fragmentation spectra. An algorithm (ISIS: in silico identification software) and its implementation are presented and show great promise in generating in silico spectra of lipids for the purpose of structural identification. Instead of using chemical reaction rate equations or rules-based fragmentation libraries, the algorithm uses machine learning to find accurate bond cleavage rates in a mass spectrometer employing collision-induced dissocia-tion tandem mass spectrometry. A preliminary test of the algorithm with 45 lipids from a subset of lipid classes shows both high sensitivity and specificity.

  1. Open source libraries and frameworks for mass spectrometry based proteomics: A developer's perspective☆

    Science.gov (United States)

    Perez-Riverol, Yasset; Wang, Rui; Hermjakob, Henning; Müller, Markus; Vesada, Vladimir; Vizcaíno, Juan Antonio

    2014-01-01

    Data processing, management and visualization are central and critical components of a state of the art high-throughput mass spectrometry (MS)-based proteomics experiment, and are often some of the most time-consuming steps, especially for labs without much bioinformatics support. The growing interest in the field of proteomics has triggered an increase in the development of new software libraries, including freely available and open-source software. From database search analysis to post-processing of the identification results, even though the objectives of these libraries and packages can vary significantly, they usually share a number of features. Common use cases include the handling of protein and peptide sequences, the parsing of results from various proteomics search engines output files, and the visualization of MS-related information (including mass spectra and chromatograms). In this review, we provide an overview of the existing software libraries, open-source frameworks and also, we give information on some of the freely available applications which make use of them. This article is part of a Special Issue entitled: Computational Proteomics in the Post-Identification Era. Guest Editors: Martin Eisenacher and Christian Stephan. PMID:23467006

  2. Hot Star Extension to the Hubble Space Telescope Stellar Spectral Library

    Science.gov (United States)

    Khan, Islam; Worthey, Guy

    2017-01-01

    CCD spectra of 36 stars were obtained from the Space Telescope Imaging Spectrograph (STIS) installed in the Hubble Space Telescope (HST) using three low resolution gratings - G230LB, G430L, and G750L, combined in processing to make single, continuous spectra from 0.2 to 1.0 micrometers. These spectra will be added to the Next Generation Stellar Library (NGSL) after completing the data analysis, reduction, and the required corrections. The stars include normal O-type stars, helium-burning stars, and post-asymptotic giant branch (PAGB) stars. Difficult steps in the data reduction process were removing the cosmic rays from the raw images and defringing of the G750L spectra using fringe flats. Most stars have detectable dust extinction. To aid in analysis, synthetic spectra were generated with various effective temperatures and surface gravities. A five parameter analytic model for the dust extinction correction was adopted. The parameters were varied in order to fit especially the ultraviolet portion of the observed and comparison synthetic spectra. Cross-correlation was used to bring the spectra to a common, final, zero velocity wavelength scale. Some star temperatures obtained from fitting synthetic versus observed spectra vary significantly from literature values. The dust extinction correction parameters also varied for several stars, mostly O stars, indicating variations in dust properties for different lines of sight. Analysis of scattered light effects showed that it was significant only for our two coolest stars.Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555.Support for this work was provided by NASA through grant number HST-GO-14141 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.

  3. New bright optical spectrophotometric standards: A-type stars from the STIS Next Generation Spectral Library

    CERN Document Server

    Prieto, Carlos Allende

    2015-01-01

    Exoplanets have sparked interest in extremely high signal-to-noise ratio spectroscopic observations of very bright stars, in a regime where flux calibrators, in particular DA white dwarfs, are not available. We argue that A-type stars offer a useful alternative and reliable space-based spectrophotometry is now available for a number of bright ones in the range 3spectral range to 400-800 nm, since our models have difficulties to reproduce the observed fluxes in the near-infrared and, especially, in the near-UV, where the discrepancies rise up to ~ 10%. Based on our model fits, we derive angular diameters with an estimated accuracy of about 1%.

  4. Comprehensive Assignment of Mass Spectral Signatures from Individual Bacillus atrophaeus Spores in Matrix-Free Bioaerosol Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, A; Pitesky, M; Steele, P; Tobias, H; Fergenson, D P; Horn, J; Russell, S C; Czerwieniec, G; Lebrilla, C; Gard, E E; Frank, M

    2004-10-22

    We have conducted studies to fully characterize the mass spectral signature of individual Bacillus atrophaeus, previously known as Bacillus subtilis var niger or Bacillus globigii, spores obtained in matrix-free bioaerosol mass spectrometry (BAMS). Mass spectra of spores grown in unlabeled, {sup 13}C-labeled and {sup 15}N-labeled growth media are used to determine the number of carbon and nitrogen atoms associated with each mass peak. To determine the parent ion structure associated with fragment ions present in the spore spectra, the mass-to-charge (m/z) fragmentation pattern of several chemical standards was obtained. Our results agree with prior assignments of dipicolinic acid, amino acids and calcium complex ions made in the spore mass spectra. Identity of several previously unidentified mass peaks, key to recognition of Bacillus spore by matrix-free BAMS, is revealed. Specifically, a set of fragment peaks in the negative polarity is shown to be consistent with the fragmentation pattern of purine nucleobase containing compounds. The identity of m/z=+74, a marker peak that helps discriminate Bacillus atrophaeus from Bacillus thuringiensis spores grown in rich medium, is surprisingly a non-description, viz. [N{sub 1}C{sub 4}H{sub 12}]{sup +}. A probable precursor molecule for the [N{sub 1}C{sub 4}H{sub 12}]{sup +} ion observed in spore spectra is trimethyl glycine ({sup +}N(CH{sub 3}){sub 3}CH{sub 2}COOH) that produces a m/z=74 peak in presence of dipicolinic acid.

  5. Applications of a catch and release electrospray ionization mass spectrometry assay for carbohydrate library screening.

    Science.gov (United States)

    El-Hawiet, Amr; Shoemaker, Glen K; Daneshfar, Rambod; Kitova, Elena N; Klassen, John S

    2012-01-03

    Applications of a catch and release electrospray ionization mass spectrometry (CaR-ESI-MS) assay for screening carbohydrate libraries against target proteins are described. Direct ESI-MS measurements were performed on solutions containing a target protein (a single chain antibody, an antigen binding fragment, or a fragment of a bacterial toxin) and a library of carbohydrates containing multiple specific ligands with affinities in the 10(3) to 10(6) M(-1) range. Ligands with moderate affinity (10(4) to 10(6) M(-1)) were successfully detected from mixtures containing >200 carbohydrates (at concentrations as low as 0.25 μM each). Additionally, the absolute affinities were estimated from the abundance of free and ligand-bound protein ions determined from the ESI mass spectrum. Multiple low affinity ligands (~10(3) M(-1)) were successfully detected in mixtures containing >20 carbohydrates (at concentrations of ~10 μM each). However, identification of specific interactions required the use of the reference protein method to correct the mass spectrum for the occurrence of nonspecific carbohydrate-protein binding during the ESI process. The release of the carbohydrate ligands, as ions, was successfully demonstrated using collision-induced dissociation performed on the deprotonated ions of the protein-carbohydrate complexes. The use of ion mobility separation, performed on deprotonated carbohydrate ions following their release from the complex, allowed for the positive identification of isomeric ligands.

  6. Automated work-flow for processing high-resolution direct infusion electrospray ionization mass spectral fingerprints

    DEFF Research Database (Denmark)

    Hansen, Michael Adsetts Edberg; Smedsgaard, Jørn

    2007-01-01

    The use of mass spectrometry (MS) is pivotal in analyses of the metabolome and presents a major challenge for subsequent data processing. While the last few years have given new high performance instruments, there has not been a comparable development in data processing. In this paper we discuss...... an automated data processing pipeline to compare large numbers of fingerprint spectra from direct infusion experiments analyzed by high resolution MS. We describe some of the intriguing problems that have to be addressed. starting with the conversion and pre-processing of the raw data to the final data...... analysis. Illustrated on the direct infusion analysis (ESI-TOF-MS) of complex mixtures the method exploits the full quality of the high-resolution present in the mass spectra. Although the method is illustrated as a new library search method for high resolution MS, we demonstrate that the output...

  7. Spectral Functions in V-QCD with Matter: Masses, Susceptibilities, Diffusion and Conductivity

    CERN Document Server

    Iatrakis, Ioannis

    2014-01-01

    We consider a holographic model of QCD in the Veneziano limit of a large number of colors $N_c$ and flavors $N_f$ but fixed $x=N_f/N_c$ (V-QCD). The model exhibits a first order deconfined but chirally broken transition, followed by a second order chirally restored transition in the $\\mu-T$ plane for a range of plausible holographic parameters. We study the quasi-normal mode spectrum, and derive the pertinent vector and axial spectral functions across the transition regions. The pole masses, susceptibilities, diffusion constants and electric conductivity are also discussed. In particular, the pole masses are found to survive the deconfining transition, to quickly dissolve in the the chirally restored phase by developing substantial widths. The flavor electric conductivities arise sharply in the transition region. The flavor susceptibility is shown to be consistent with the one derived from bulk thermodynamics.

  8. msmsEval: tandem mass spectral quality assignment for high-throughput proteomics

    Directory of Open Access Journals (Sweden)

    Cartwright Hugh M

    2007-02-01

    Full Text Available Abstract Background In proteomics experiments, database-search programs are the method of choice for protein identification from tandem mass spectra. As amino acid sequence databases grow however, computing resources required for these programs have become prohibitive, particularly in searches for modified proteins. Recently, methods to limit the number of spectra to be searched based on spectral quality have been proposed by different research groups, but rankings of spectral quality have thus far been based on arbitrary cut-off values. In this work, we develop a more readily interpretable spectral quality statistic by providing probability values for the likelihood that spectra will be identifiable. Results We describe an application, msmsEval, that builds on previous work by statistically modeling the spectral quality discriminant function using a Gaussian mixture model. This allows a researcher to filter spectra based on the probability that a spectrum will ultimately be identified by database searching. We show that spectra that are predicted by msmsEval to be of high quality, yet remain unidentified in standard database searches, are candidates for more intensive search strategies. Using a well studied public dataset we also show that a high proportion (83.9% of the spectra predicted by msmsEval to be of high quality but that elude standard search strategies, are in fact interpretable. Conclusion msmsEval will be useful for high-throughput proteomics projects and is freely available for download from http://proteomics.ucd.ie/msmseval. Supports Windows, Mac OS X and Linux/Unix operating systems.

  9. Studies on azaspiracid biotoxins. II. Mass spectral behavior and structural elucidation of azaspiracid analogs.

    Science.gov (United States)

    Brombacher, Stephan; Edmonds, Suzanne; Volmer, Dietrich A

    2002-01-01

    In this report, the mass spectral analysis of azaspiracid biotoxins is described. Specifically, the collision-induced dissociation (CID) behavior and differences between CID spectra obtained on a triple-quadrupole, a quadrupole time-of-flight, and an ion-trap mass spectrometer are addressed here. The CID spectra obtained on the triple-quadrupole mass spectrometer allowed the classification of the major product ions of the five investigated compounds (AZA 1-5) into five distinct fragment ion groups, according to the backbone cleavage positions. Although the identification of unknown azaspiracids was difficult based on CID alone, the spectra provided sufficient structural information to allow confirmation of known azaspiracids in marine samples. Furthermore, we were able to detect two new azaspiracid analogs (AZA 1b and 6) in our samples and provide a preliminary structural analysis. The proposed dissociation pathways under tandem mass spectrometry (MS/MS) conditions were confirmed by a comparison with accurate mass data from electrospray quadrupole time-of-flight MS/MS experiments. Regular sequential MS(n) analysis on an ion-trap mass spectrometer was more restricted in comparison to the triple-quadrupole mass spectrometer, because the azaspiracids underwent multiple [M + H - nH(2)O](+) (n = 1-6) losses from the precursor ion under CID. Thus, the structural information obtained from MS(n) experiments was somewhat limited. To overcome this limitation, we developed a wide-range excitation technique using a 180-u window that provided results comparable to the triple-quadrupole instrument. To demonstrate the potential of the method, we applied it to the analysis of degraded azaspiracids from mussel tissue extracts.

  10. Library screening by means of mass spectrometry (MS) binding assays-exemplarily demonstrated for a pseudostatic library addressing γ-aminobutyric acid (GABA) transporter 1 (GAT1).

    Science.gov (United States)

    Sindelar, Miriam; Wanner, Klaus T

    2012-09-01

    In the present study, the application of mass spectrometry (MS) binding assays as a tool for library screening is reported. For library generation, dynamic combinatorial chemistry (DCC) was used. These libraries can be screened by means of MS binding assays when appropriate measures are taken to render the libraries pseudostatic. That way, the efficiency of MS binding assays to determine ligand binding in compound screening with the ease of library generation by DCC is combined. The feasibility of this approach is shown for γ-aminobutyric acid (GABA) transporter 1 (GAT1) as a target, representing the most important subtype of the GABA transporters. For the screening, hydrazone libraries were employed that were generated in the presence of the target by reacting various sets of aldehydes with a hydrazine derivative that is delineated from piperidine-3-carboxylic acid (nipecotic acid), a common fragment of known GAT1 inhibitors. To ensure that the library generated is pseudostatic, a large excess of the nipecotic acid derivative is employed. As the library is generated in a buffer system suitable for binding and the target is already present, the mixtures can be directly analyzed by MS binding assays-the process of library generation and screening thus becoming simple to perform. The binding affinities of the hits identified by deconvolution were confirmed in conventional competitive MS binding assays performed with single compounds obtained by separate synthesis. In this way, two nipecotic acid derivatives exhibiting a biaryl moiety, 1-{2-[2'-(1,1'-biphenyl-2-ylmethylidene)hydrazine]ethyl}piperidine-3-carboxylic acid and 1-(2-{2'-[1-(2-thiophenylphenyl)methylidene]hydrazine}ethyl)piperidine-3-carboxylic acid, were found to be potent GAT1 ligands exhibiting pK(i) values of 6.186 ± 0.028 and 6.229 ± 0.039, respectively. This method enables screening of libraries, whether generated by conventional chemistry or DCC, and is applicable to all kinds of targets including

  11. MzJava: An open source library for mass spectrometry data processing.

    Science.gov (United States)

    Horlacher, Oliver; Nikitin, Frederic; Alocci, Davide; Mariethoz, Julien; Müller, Markus; Lisacek, Frederique

    2015-11-03

    Mass spectrometry (MS) is a widely used and evolving technique for the high-throughput identification of molecules in biological samples. The need for sharing and reuse of code among bioinformaticians working with MS data prompted the design and implementation of MzJava, an open-source Java Application Programming Interface (API) for MS related data processing. MzJava provides data structures and algorithms for representing and processing mass spectra and their associated biological molecules, such as metabolites, glycans and peptides. MzJava includes functionality to perform mass calculation, peak processing (e.g. centroiding, filtering, transforming), spectrum alignment and clustering, protein digestion, fragmentation of peptides and glycans as well as scoring functions for spectrum-spectrum and peptide/glycan-spectrum matches. For data import and export MzJava implements readers and writers for commonly used data formats. For many classes support for the Hadoop MapReduce (hadoop.apache.org) and Apache Spark (spark.apache.org) frameworks for cluster computing was implemented. The library has been developed applying best practices of software engineering. To ensure that MzJava contains code that is correct and easy to use the library's API was carefully designed and thoroughly tested. MzJava is an open-source project distributed under the AGPL v3.0 licence. MzJava requires Java 1.7 or higher. Binaries, source code and documentation can be downloaded from http://mzjava.expasy.org and https://bitbucket.org/sib-pig/mzjava. This article is part of a Special Issue entitled: Computational Proteomics.

  12. A Global Spectral Study of Stellar-Mass Black Holes with Unprecedented Sensitivity

    Science.gov (United States)

    Garci, Javier

    There are two well established populations of black holes: (i) stellar-mass black holes with masses in the range 5 to 30 solar masses, many millions of which are present in each galaxy in the universe, and (ii) supermassive black holes with masses in the range millions to billions of solar masses, which reside in the nucleus of most galaxies. Supermassive black holes play a leading role in shaping galaxies and are central to cosmology. However, they are hard to study because they are dim and they scarcely vary on a human timescale. Luckily, their variability and full range of behavior can be very effectively studied by observing their stellar-mass cousins, which display in miniature the full repertoire of a black hole over the course of a single year. The archive of data collected by NASA's Rossi X-ray Timing Explorer (RXTE) during its 16 year mission is of first importance for the study of stellar-mass black holes. While our ultimate goal is a complete spectral analysis of all the stellar-mass black hole data in the RXTE archive, the goal of this proposal is the global study of six of these black holes. The two key methodologies we bring to the study are: (1) Our recently developed calibration tool that increases the sensitivity of RXTE's detector by up to an order of magnitude; and (2) the leading X-ray spectral "reflection" models that are arguably the most effective means currently available for probing the effects of strong gravity near the event horizon of a black hole. For each of the six black holes, we will fit our models to all the archived spectral data and determine several key parameters describing the black hole and the 10-million-degree gas that surrounds it. Of special interest will be our measurement of the spin (or rate of rotation) of each black hole, which can be as high as tens of thousands of RPM. Profoundly, all the properties of an astronomical black hole are completely defined by specifying its spin and its mass. The main goal of this

  13. SHIELD: EVLA HI Spectral Line Observations of Low-mass Dwarfs

    Science.gov (United States)

    Miazzo, Masao; Ruvolo, Elizabeth; Cannon, John M.; McNichols, Andrew; Teich, Yaron; Adams, Elizabeth A.; Giovanelli, Riccardo; Haynes, Martha P.; McQuinn, Kristen B.; Salzer, John Joseph; Skillman, Evan D.; Dolphin, Andrew E.; Elson, Edward C.; Haurberg, Nathalie C.; Huang, Shan; Janowiecki, Steven; Jozsa, Gyula; Leisman, Luke; Ott, Juergen; Papastergis, Emmanouil; Rhode, Katherine L.; Saintonge, Amelie; Van Sistine, Angela; Warren, Steven R.

    2017-01-01

    The “Survey of HI in Extremely Low-mass Dwarfs” (SHIELD) is a multiwavelength study of local volume low-mass galaxies. Using the now-complete Arecibo Legacy Fast ALFA (ALFALFA) source catalog, 82 systems are identified that meet distance, line width, and HI flux criteria for being gas-rich, low-mass galaxies. These systems harbor neutral gas reservoirs smaller than 3x10^7 M_sun, thus populating the faint end of the HI mass function with statistical confidence for the first time. Here we present new Karl G. Jansky Very Large Array D-configuration HI spectral line observations of 32 previously unobserved galaxies. These low angular resolution (~40" beam) images localize the HI gas; with a few exceptions, the HI gas is co-spatial with the optical centers of the galaxies. These images provide the first glimpse of the neutral interstellar medium in these systems.Support for this work was provided by NSF grant 1211683 to JMC at Macalester College.

  14. Mass Audience Circulation: Library Service in the U.S.S.R.

    Science.gov (United States)

    Zhidkov, Grigory

    1983-01-01

    Presents overview of state of Soviet Union library service comprising 350,000 libraries, including national, governmental department, and public group (trade unions, professional associations) libraries. Training of Soviet librarians, library cooperation, national planning and funding, cultural exchange and cooperation, supporting international…

  15. Application of visual basic in high-throughput mass spectrometry-directed purification of combinatorial libraries.

    Science.gov (United States)

    Li, B; Chan, E C Y

    2003-01-01

    We present an approach to customize the sample submission process for high-throughput purification (HTP) of combinatorial parallel libraries using preparative liquid chromatography electrospray ionization mass spectrometry. In this study, Visual Basic and Visual Basic for Applications programs were developed using Microsoft Visual Basic 6 and Microsoft Excel 2000, respectively. These programs are subsequently applied for the seamless electronic submission and handling of data for HTP. Functions were incorporated into these programs where medicinal chemists can perform on-line verification of the purification status and on-line retrieval of postpurification data. The application of these user friendly and cost effective programs in our HTP technology has greatly increased our work efficiency by reducing paper work and manual manipulation of data.

  16. High-throughput screening of small molecule libraries using SAMDI mass spectrometry.

    Science.gov (United States)

    Gurard-Levin, Zachary A; Scholle, Michael D; Eisenberg, Adam H; Mrksich, Milan

    2011-07-11

    High-throughput screening is a common strategy used to identify compounds that modulate biochemical activities, but many approaches depend on cumbersome fluorescent reporters or antibodies and often produce false-positive hits. The development of "label-free" assays addresses many of these limitations, but current approaches still lack the throughput needed for applications in drug discovery. This paper describes a high-throughput, label-free assay that combines self-assembled monolayers with mass spectrometry, in a technique called SAMDI, as a tool for screening libraries of 100,000 compounds in one day. This method is fast, has high discrimination, and is amenable to a broad range of chemical and biological applications.

  17. The microscopic Twisted Mass Dirac spectrum and the spectral determination of the LECs of Wilson $\\chi$-PT

    CERN Document Server

    Cichy, Krzysztof; Splittorff, K; Zafeiropoulos, Savvas

    2015-01-01

    We present the comparison of the analytical microscopic spectral density for lattice QCD with $N_{\\rm f}=2$ twisted mass fermions with the one obtained on the lattice utilizing configurations produced by the ETM collaboration. We extract estimates for the chiral condensate as well as the low-energy constant $W_8$ of Wilson $\\chi$-PT by employing spectral information of the Wilson Dirac operator with fixed index at finite volume.

  18. Prediction of Mass Spectral Response Factors from Predicted Chemometric Data for Druglike Molecules

    Science.gov (United States)

    Cramer, Christopher J.; Johnson, Joshua L.; Kamel, Amin M.

    2017-02-01

    A method is developed for the prediction of mass spectral ion counts of drug-like molecules using in silico calculated chemometric data. Various chemometric data, including polar and molecular surface areas, aqueous solvation free energies, and gas-phase and aqueous proton affinities were computed, and a statistically significant relationship between measured mass spectral ion counts and the combination of aqueous proton affinity and total molecular surface area was identified. In particular, through multilinear regression of ion counts on predicted chemometric data, we find that log10(MS ion counts) = -4.824 + c 1•PA + c 2•SA, where PA is the aqueous proton affinity of the molecule computed at the SMD(aq)/M06-L/MIDI!//M06-L/MIDI! level of electronic structure theory, SA is the total surface area of the molecule in its conjugate base form, and c 1 and c 2 have values of -3.912 × 10-2 mol kcal-1 and 3.682 × 10-3 Å-2. On a 66-molecule training set, this regression exhibits a multiple R value of 0.791 with p values for the intercept, c 1, and c 2 of 1.4 × 10-3, 4.3 × 10-10, and 2.5 × 10-6, respectively. Application of this regression to an 11-molecule test set provides a good correlation of prediction with experiment ( R = 0.905) albeit with a systematic underestimation of about 0.2 log units. This method may prove useful for semiquantitative analysis of drug metabolites for which MS response factors or authentic standards are not readily available.

  19. Mass estimation of MAXI J1659-152 during spectral and temporal analsyis with TCAF and POS models

    Science.gov (United States)

    Molla, Aslam Ali; Debnath, Dipak; Chakrabarti, Sandip Kumar; Mondal, Santanu; Jana, Arghajit; Chatterjee, Debjit

    2016-07-01

    The Galactic transient black hole candidate (BHC) MAXI J1659-152 showed its first X-ray outburst on 25th Spet. 2010. We make a detailed spectral and temporal study of this outburst with RXTE/PCA data. The spectral analysis was made with Two Component Advective Flow (TCAF) model fits file as an additive table model in XSPEC. While fitting spectra with TCAF, we note that model fitted normalization (N) remains almost constant (129.7 - 146.3) which lead us to calculate mass of the black hole (BH). We then refitted all the spectra with fixed normalization value of 139 (calculated from weighted averaging of the N values), and found that mass of the BH comes in the range of 4.69-7.75 M_Sun. It is to be noted that in TCAF model fits file, mass is an input parameter. We also calculted mass of the BH, with our study of the QPO frequency evolution during declining phase of the outburst with the Propagating Oscillatory Shock (POS) model. We observe that in the declining phase of the outburst the shock moves away from the black hole as the QPO frequency decreases. We obtain our best fit of QPO evolution by using mass of the BH at 6 M_Sun and acceptable fit (reduced chisq value < 1.5) for the mass range of 5.08-7.38 M_Sun, which lie within the range of mass obtained from our spectral fit. So, from the study of spectral and temporal variability of this source we conclude the probable mass range of the black hole to be 4.69 - 7.75 M_Sun.

  20. Determination of Black Hole Masses in Galactic Black Hole Binaries using Scaling of Spectral and Variability Characteristics

    CERN Document Server

    Shaposhnikov, Nickolai

    2009-01-01

    We present a study of correlations between X-ray spectral and timing properties observed from a number of Galactic Black Hole (BH) binaries during hard-soft state spectral evolution. We analyze 17 transition episodes from 8 BH sources observed with RXTE. Our scaling technique for BH mass determination uses a correlation between spectral index and quasi-periodic oscillation (QPO) frequency. In addition, we use a correlation between index and the normalization of the disk "seed" component to cross-check the BH mass determination and estimate the distance to the source. While the index-QPO correlations for two given sources contain information on the ratio of the BH masses in those sources, the index-normalization correlations depend on the ratio of the BH masses and the distance square ratio. In fact, the index-normalization correlation also discloses the index-mass accretion rate saturation effect given that the normalization of disk "seed" photon supply is proportional to the disk mass accretion rate. We pres...

  1. Advanced spectral imaging for noninvasive microanalysis of cultural heritage materials: review of application to documents in the U.S. Library of Congress.

    Science.gov (United States)

    France, Fenella G

    2011-06-01

    Hyperspectral imaging was originally developed for remote sensing and astronomical applications, but adaptations of this technology have been of great benefit to the preservation of cultural heritage. Developments in noninvasive analytical techniques have advanced the preservation of cultural heritage materials by enabling the identification and analysis of a range of materials, utilizing their unique spectral response to nondestructively determine chemical composition, and determining states of deterioration and change due to environmental conditions. When used as a tool for noninvasive characterization of cultural heritage, these spectral imaging systems allow the collection of chemical identification information about materials without sampling, which is a critical factor for cultural heritage materials. The United States Library of Congress has been developing the application of hyperspectral imaging to the preservation and analysis of cultural heritage materials as a powerful noncontact technique. It allows noninvasive characterization of materials, by identifying and characterizing colorants, inks, and substrates with narrow-band illumination to protect the object while also monitoring deterioration or changes due to exhibit and other environmental conditions. Contiguous illumination from the ultraviolet, visible, and infrared spectral regions allows the capture of lost, obscured, and deteriorated information. The resulting image cube allows greater capabilities for mapping and coordinating a range of complementary chemical and spectral analyses. The capabilities of this technique are illustrated by a review of results from analysis of the Waldseemüller World Map, the L'Enfant plan for Washington, D.C., and the first draft of the U.S. Declaration of Independence.

  2. Do we really need large spectral libraries for the assessment of soil organic carbon at local scale?

    Science.gov (United States)

    Guerrero, César; Wetterlind, Johanna; Stenberg, Bo; Viscarra Rossel, Raphael A.; Zornoza, Raúl; Maestre, Fernando T.; Mouazen, Abdul M.; Kuang, Boyan; Damián Ruiz-Sinoga, José; Gabarrón-Galeote, Miguel A.

    2014-05-01

    Spiking is an approach to improve the accuracy of large-scale spectroscopic models when they are used to predict at local scale. But, if models are to be spiked, do we really need large-sized spectral libraries? Different calibrations relating the SOC and NIR spectra were obtained using PLS as regression method: i) model #1: local-scale model (n=40); ii) model #2: local-scale model (n=88); iii) model #3: provincial-scale model (n=147); iv) model #4: provincial-scale model, constructed with 50% of samples used in model #3 (n=73); v) model #5: provincial-scale model, constructed with 25% of samples used in model #3 (n=36); vi) model #6: national-scale model (n=1096); vii) model #7: national-scale model, constructed with 33% of samples used in model #6 (n=362). Each of these models was used to predict the SOC contents in target site samples. In this work, nine target sites were evaluated. Each target site is a relatively small area (from several hectares to a few square kilometers), where a dense sampling was made. The coefficient of the determination (R2), root mean square error of prediction (RMSEP), bias, standard error of prediction (SEP) and the ratio of performance to deviance (RPD) were calculated pooling the predictions of the nine target sites. In overall, more than 900 local samples were predicted. The highest R2 values were obtained with the national-scale models (R2 >0.85), and the lowest R2 values were obtained with the models of small size. In general, the RMSEP tended to decrease with the increase of the models size. However, the predictions obtained with the large-sized models were clearly biased, and despite the high R2 values, the RPD values were below 1.2. We also obtained predictions when these models were spiked with eight local samples (i.e., from the target site). After spiking, the predictions obtained with the small-sized models were substantially improved. As example of the changes due to spiking, the predictions obtained with the smallest

  3. The spectral type of CHS7797 - an intriguing very low mass periodic variable in the Orion Nebula Cluster

    CERN Document Server

    Rodriguez-Ledesma, M V; Pintado, O; Boudreault, S; Hessman, F; Herbst, W

    2013-01-01

    We present the spectroscopic characterization of the unusual high-amplitude very low mass pre-main-sequence periodic variable CHS7797. This study is based on optical medium-resolution (R=2200) spectroscopy in the 6450-8600 A range, carried out with GMOS-GEMINI-S in March 2011. Observations of CHS7797 have been carried out at two distinct phases of the 17.8d period, namely at maximum and four days before maximum. Four different spectral indices were used for the spectral classification at these two phases, all of them well-suited for spectral classification of young and obscured late M dwarfs. In addition, the gravity-sensitive NaI (8183/8195 A) and KI (7665/7699 A) doublet lines were used to confirm the young age of CHS7797. From the spectrum obtained at maximum light we derived a spectral type (SpT) of M6.05, while for the spectrum taken four days before maximum the derived SpT is M5.75. The derived SpTs confirm that CHS7797 has a mass in the stellar-substellar boundary mass range. In addition, the small dif...

  4. Co-registered Topographical, Band Excitation Nanomechanical, and Mass Spectral Imaging Using a Combined Atomic Force Microscopy/Mass Spectrometry Platform.

    Science.gov (United States)

    Ovchinnikova, Olga S; Tai, Tamin; Bocharova, Vera; Okatan, Mahmut Baris; Belianinov, Alex; Kertesz, Vilmos; Jesse, Stephen; Van Berkel, Gary J

    2015-04-28

    The advancement of a hybrid atomic force microscopy/mass spectrometry imaging platform demonstrating the co-registered topographical, band excitation nanomechanical, and mass spectral imaging of a surface using a single instrument is reported. The mass spectrometry-based chemical imaging component of the system utilized nanothermal analysis probes for pyrolytic surface sampling followed by atmospheric pressure chemical ionization of the gas-phase species produced with subsequent mass analysis. The basic instrumental setup and operation are discussed, and the multimodal imaging capability and utility are demonstrated using a phase-separated polystyrene/poly(2-vinylpyridine) polymer blend thin film. The topography and band excitation images showed that the valley and plateau regions of the thin film surface were comprised primarily of one of the two polymers in the blend with the mass spectral chemical image used to definitively identify the polymers at the different locations. Data point pixel size for the topography (390 nm × 390 nm), band excitation (781 nm × 781 nm), and mass spectrometry (690 nm × 500 nm) images was comparable and submicrometer in all three cases, but the data voxel size for each of the three images was dramatically different. The topography image was uniquely a surface measurement, whereas the band excitation image included information from an estimated 20 nm deep into the sample and the mass spectral image from 110 to 140 nm in depth. Because of this dramatic sampling depth variance, some differences in the band excitation and mass spectrometry chemical images were observed and were interpreted to indicate the presence of a buried interface in the sample. The spatial resolution of the chemical image was estimated to be between 1.5 and 2.6 μm, based on the ability to distinguish surface features in that image that were also observed in the other images.

  5. The redshift and the blueshift of spectral lines and the motion of mass-points in gravitational fields of photon stars

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao-fan; YANG Xue-dong; CHEN Zhi-lai

    2007-01-01

    The redshift and the blueshift of spectral lines in gravitational fields of photon stars are studied when the observing and emitting points of the spectral lines locate at different positions. And the motion of masspoints is also studied. The studies show that the redshift and the blueshift of spectral lines in gravitational fields of photon stars can be arbitrarily positive, and the motion of mass-points in gravitational fields of photon stars can be used to determine the mass of photon stars.

  6. The spectral energy distribution and mass-loss history of IRC+10420

    NARCIS (Netherlands)

    Oudmaijer, RD; Matthews, HE; Blommaert, JADL; Sahu, KC

    1996-01-01

    We present a study of the spectral energy distribution of the peculiar hypergiant IRC + 10420. To this end we have collected published photometry of IRC + 10420 and obtained some new data, in order to construct the spectral energy distribution and fit it with a radiative transfer model. In addition

  7. The infrared spectral features of circumstellar envelope of evolved low-and intermediate-mass stars

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ke; JIANG BiWei

    2008-01-01

    The circumstellar envelope of evolved stars of low-and intermediate-mass is an important site for dust formation. In comparison with the interstellar medium, they have more types of organics and different types of inorganics. Various infrared features in the circumstellar envelope can reveal the composition and abundance of dust, as well as the chemical and physical conditions of the circumstellar shell. Infrared features and their carriers are different in the C-rich or O-rich environment, and the mixed-environment where the C-rich and O-rich circumstellar materials co-exist. The C-rich sources exhibit a series of spectral features which are attrib-uted to organic molecules. They also show two prominent features at 21 μm and 30 μm which emit a large portion of infrared radiation. The O-rich sources exhibit the strong 9.7 μm and 18 μm features attributed to the Si-O bending and O-Si-O stretching modes of amorphous silicate dust. With the ISO/SWS spectrometer, about 50 narrow bands are identified with the crystalline silicate grains, mainly forsterite and enstatite. In addition, a series of features, at 13 μm, 16.8 μm, 19.5 μm and 31.8 μm, appearing to be correlated with each other, are attributed to oxides. Some objects simultaneously show the C-rich and O-rich features, e.g. some C-rich sources have silicate features. There is no well-accepted interpretation for such mixed appearance, though a binary model is suggested.

  8. The infrared spectral features of circumstellar envelope of evolved low- and intermediate-mass stars

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The circumstellar envelope of evolved stars of low- and intermediate-mass is an important site for dust formation. In comparison with the interstellar medium, they have more types of organics and different types of inorganics. Various infrared features in the circumstellar envelope can reveal the composition and abundance of dust, as well as the chemical and physical conditions of the circumstellar shell. Infrared features and their carriers are different in the C-rich or O-rich environment, and the mixed-environment where the C-rich and O-rich circumstellar materials co-exist. The C-rich sources exhibit a series of spectral features which are attrib- uted to organic molecules. They also show two prominent features at 21 μm and 30 μm which emit a large portion of infrared radiation. The O-rich sources exhibit the strong 9.7 μm and 18 μm features attributed to the Si-O bending and O-Si-O stretching modes of amorphous silicate dust. With the ISO/SWS spectrometer, about 50 narrow bands are identified with the crystalline silicate grains, mainly forsterite and enstatite. In addition, a series of features, at 13 μm, 16.8 μm, 19.5 μm and 31.8 μm, appearing to be correlated with each other, are attributed to oxides. Some objects simultaneously show the C-rich and O-rich features, e.g. some C-rich sources have silicate features. There is no well-accepted interpretation for such mixed appearance, though a binary model is suggested.

  9. Analysis of X-ray spectral variability and black hole mass determination of the NLS1 galaxy Mrk 766

    CERN Document Server

    Giacche`, S; Titarchuk, L

    2013-01-01

    We present an XMM-Newton time-resolved spectral analysis of the NLS1 galaxy Mrk 766. We analyse eight available observations of the EPIC-pn camera taken between May 2000 and June 2005 to investigate the X-ray spectral variability as produced by changes in the mass accretion rate. The 0.2-10 keV spectra are extracted in time bins longer than 3 ks to accurately trace the variations of the best fit parameters of our adopted Comptonisation spectral model. We test a bulk-motion Comptonisation (BMC) model which is in general applicable to any physical system powered by accretion onto a compact object, and assumes that soft seed photons are efficiently up-scattered via inverse Compton scattering in a hot and dense electron corona. The Comptonised spectrum has a characteristic power-law shape, whose slope was found to increase for large values of the normalisation of the seed component, that is proportional to the mass accretion rate (in Eddington units). Our baseline spectral model also includes a warm absorber lyin...

  10. Mass and Momentum Conservation of the Least-Squares Spectral Collocation Method for the Time-Dependent Stokes Equations

    Science.gov (United States)

    Kattelans, Thorsten; Heinrichs, Wilhelm

    2009-09-01

    For Stokes problems least-squares schemes have the big advantage that they require no stabilization and equal order interpolation can be used. The disadvantage of Least-Squares Finite Element Method (LSFEM) and of Least-Squares Spectral Element Method (LSSEM) is that they perform poorly with respect to conservation of mass for internal flow problems, where the LSSEM compensates this by a superior conservation of momentum. In the literature it has been shown that Least-Squares Spectral Collocation Method (LSSCM) leads to superior conservation of mass and momentum for the steady Stokes. Here, we extend the study to the time-dependent Stokes equations for an internal flow problem, where the domain is decomposed into different elements using the transfinite mapping of Gordon and Hall. Minimizing the influence of round-off errors we use QR decomposition for solving the resulting overdetermined algebraic systems instead of forming normal equations.

  11. New Insights into AGN Mass Outflows: Detailed Study of the Spectral Properties of NGC 4151

    Science.gov (United States)

    Denes Couto, Jullianna

    2017-08-01

    Active Galactic Nuclei (AGNs) exist in a few percent of all massive galaxies. It is believed that AGNs are powered by accretion of matter onto a supermassive black hole (SMBH), generating in the process huge amounts of radiation that span the entire electromagnetic spectrum. In turn, this also triggers the so-called AGN Feedback phenomenon, by inducing the formation of accretion disk winds (or outflows) that accelerate highly ionized gas outwards and affect the intergalactic medium of the host galaxy, reducing star formation rates and preventing bulge growth. It has been suggested that a dominant component of mass outflows is observable in the X-rays, and there are a limited number of detailed studies of single objects for which the relation between outflows and power of the central engine can be determined directly. The Seyfert 1.5 galaxy NGC 4151 is a great study candidate, given its proximity (14.077 Mpc, z = 0.0033), X-ray brightness and orientation. Over the past decades, it has been the target of many single and multiwavelength observations, and its heavily absorbed X-ray spectrum and complex absorption features have been extensively stud- ied and characterized. I have investigated the relationship between the long term X-ray spectral variability in and its intrinsic absorption, by comparing our 2014 simultaneous ultraviolet/X-Ray observations taken with Hubble Space Telescope Imaging Spectrometer (STIS) Echelle and Chandra High Energy Transmission Grating Spectrometer (HETGS) with archival observations from Chandra, XMM-Newton and Suzaku. The observations were divided into "high" and "low" flux states, with the low states showing strong and unabsorbed extended emission at energies below 2 keV. The X-ray model consists of a broken powerlaw, neutral reflection and two dominant absorption components, a high and a low ionization component, which are present in all epochs. The model fittings suggest that the absorbers are very stable, with the principal changes

  12. Determination of single particle mass spectral signatures from light-duty vehicle emissions.

    Science.gov (United States)

    Sodeman, David A; Toner, Stephen M; Prather, Kimberly A

    2005-06-15

    In this study, 28 light-duty gasoline vehicles (LDV) were operated on a chassis dynamometer at the California Air Resources Board Haagen-Smit Facility in El Monte, CA. The mass spectra of individual particles emitted from these vehicles were measured using aerosol time-of-flight mass spectrometry (ATOFMS). A primary goal of this study involves determining representative size-resolved single particle mass spectral signatures that can be used in future ambient particulate matter source apportionment studies. Different cycles were used to simulate urban driving conditions including the federal testing procedure (FTP), unified cycle (UC), and the correction cycle (CC). The vehicles were selected to span a range of catalytic converter (three-way, oxidation, and no catalysts) and engine technologies (vehicles models from 1953 to 2003). Exhaust particles were sampled directly from a dilution and residence chamber system using particle sizing instruments and an ATOFMS equipped with an aerodynamic lens (UF-ATOFMS) analyzing particles between 50 and 300 nm. On the basis of chemical composition, 10 unique chemical types describe the majority of the particles with distinct size and temporal characteristics. In the ultrafine size range (between 50 and 100 nm), three elemental carbon (EC) particle types dominated, all showing distinct EC signatures combined with Ca, phosphate, sulfate, and a lower abundance of organic carbon (OC). The relative fraction of EC particle types decreased as particle size increased with OC particles becoming more prevalent above 100 nm. Depending on the vehicle and cycle, several distinct OC particle types produced distinct ion patterns, including substituted aromatic compounds and polycyclic aromatic hydrocarbons (PAH), coupled with other chemical species including ammonium, EC, nitrate, sulfate, phosphate, V, and Ca. The most likely source of the Ca and phosphate in the particles is attributed to the lubricating oil. Significant variability was

  13. Improving the discriminatory power of a near-infrared microscopy spectral library with a support vector machine classifier.

    Science.gov (United States)

    Fernández-Ibáñez, V; Fearn, T; Montañés, E; Quevedo, J R; Soldado, A; de la Roza-Delgado, B

    2010-01-01

    A multi-group classifier based on the support vector machine (SVM) has been developed for use with a library of 48,456 spectra measured by near-infrared reflection microscopy (NIRM) on 227 samples representing 26 animal feed ingredients and 4 possible contaminants of animal origin. The performance of the classifier was assessed by a five-fold cross-validation, dividing at the sample level. Although the overall proportion of misclassifications was 27%, almost all of these involved the confusion of pairs of similar ingredients of vegetable origin. Such confusions are unimportant in the context of the intended use of the library, which is the detection of banned ingredients in animal feed. The error rate in discrimination between permitted and banned ingredients was just 0.17%. The performance of the SVM classifier was substantially better than that of the K-nearest-neighbors method employed in previous work with the same library, for which the comparable error rates are 36% overall and 0.39% for permitted versus banned ingredients.

  14. EXPERIMENTAL TECHNIQUE FOR DETERMINATE OF MASS FRACTION OF ELEMENTS IN STEELS FOR PHOTOELECTRIC SPECTRAL METHOD

    Directory of Open Access Journals (Sweden)

    P. O. Korzoun

    2011-01-01

    Full Text Available Мethod for the measurement and selection of reference materials for photoelectric method of spectral analysis of steels (according ГОСТ 18 895 shows for research on atomic emission spectrometer DFS-71. 

  15. Archive of mass spectral data files on recordable CD-ROMs and creation and maintenance of a searchable computerized database.

    Science.gov (United States)

    Amick, G D

    1999-01-01

    A database containing names of mass spectral data files generated in a forensic toxicology laboratory and two Microsoft Visual Basic programs to maintain and search this database is described. The data files (approximately 0.5 KB/each) were collected from six mass spectrometers during routine casework. Data files were archived on 650 MB (74 min) recordable CD-ROMs. Each recordable CD-ROM was given a unique name, and its list of data file names was placed into the database. The present manuscript describes the use of search and maintenance programs for searching and routine upkeep of the database and creation of CD-ROMs for archiving of data files.

  16. Gas Chromatography and Mass Spectrometry Measurements and Protocols for Database and Library Development Relating to Organic Species in Support of the Mars Science Laboratory

    Science.gov (United States)

    Misra, P.; Garcia, R.; Mahaffy, P. R.

    2010-04-01

    An organic contaminant database and library has been developed for use with the Sample Analysis at Mars (SAM) instrumentation utilizing laboratory-based Gas Chromatography-Mass Spectrometry measurements of pyrolyzed and baked material samples.

  17. Variation in spectral and mass dimension on 3D soil image processing

    Science.gov (United States)

    Sanchez, M. E.; Tarquis, A. M.; Fabregat, J.; Andina, D.; Jimenez, J.; Crawford, J. W.

    2009-04-01

    Knowledge on three dimensional soil pore architecture is important for understanding soil processes as it controls biological, chemical and physical processes on various scales. Recent advances in non-destructive imaging, such as X-ray Computed Tomography (CT), provide several ways to analyze pore space features mainly concentrating on the visualization of soil structure. Fractal formalism has revealed as useful tool in these cases where highly complex and heterogeneous medium are studied. One of these quantifications is mass dimension (Dm) and spectral dimension (d) applied for water and gas diffusion coefficient in soil. At the same time that these techniques give a unique opportunity to quantify and describe pore space, they presents steps in their procedures on which the results depend. In this work, intact soil samples were collected from four horizons of a Brazilian soil and 3D images, of 45.1 micro-m resolution (256x256x256 voxels), were obtained. Four different threshold criteria were used to transform CT grey-scale imagery in binary imagery (pore/solid), based on the frequency of CT units. Then the threshold effect on the estimation of Dm and d, as well as their ratio was studied. Each threshold criteria had a direct influence on Dm as it has been previously reported [1], through the increase on porosity obtained. Meanwhile Dm showed a clear logarithmic relation with the apparent porosity in the image obtained for each threshold, d showed an almost linear one. In any case the increase of each one of them respect to porosity was different for each horizon. The Dm/d ratio was practically constant through all the porosity achieved in this study when Dm was estimated using all the scale range available. On the other hand, when Dm was estimated based on smaller scales this ratio depended on the threshold criteria applied to the image. This fact has a direct implication in diffusion parameters for a pore network modeling based on both fractal dimensions. [1] A

  18. FluTyper-an algorithm for automated typing and subtyping of the influenza virus from high resolution mass spectral data

    Directory of Open Access Journals (Sweden)

    Schwahn Alexander B

    2010-05-01

    Full Text Available Abstract Background High resolution mass spectrometry has been employed to rapidly and accurately type and subtype influenza viruses. The detection of signature peptides with unique theoretical masses enables the unequivocal assignment of the type and subtype of a given strain. This analysis has, to date, required the manual inspection of mass spectra of whole virus and antigen digests. Results A computer algorithm, FluTyper, has been designed and implemented to achieve the automated analysis of MALDI mass spectra recorded for proteolytic digests of the whole influenza virus and antigens. FluTyper incorporates the use of established signature peptides and newly developed naïve Bayes classifiers for four common influenza antigens, hemagglutinin, neuraminidase, nucleoprotein, and matrix protein 1, to type and subtype the influenza virus based on their detection within proteolytic peptide mass maps. Theoretical and experimental testing of the classifiers demonstrates their applicability at protein coverage rates normally achievable in mass mapping experiments. The application of FluTyper to whole virus and antigen digests of a range of different strains of the influenza virus is demonstrated. Conclusions FluTyper algorithm facilitates the rapid and automated typing and subtyping of the influenza virus from mass spectral data. The newly developed naïve Bayes classifiers increase the confidence of influenza virus subtyping, especially where signature peptides are not detected. FluTyper is expected to popularize the use of mass spectrometry to characterize influenza viruses.

  19. Validation of automated Library-Based Qualitative Screening of Pesticides by Comprehensive Two-Dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry

    NARCIS (Netherlands)

    Mol, J.G.J.; Kamp, van der H.J.; Weg, van der G.; Lee, van der M.K.; Punt, A.M.; Rijk, de T.C.

    2011-01-01

    A method for automated detection and reporting of pesticides in plant materials based on comprehensive two-dimensional GC/time-of-flight MS with library-based detection by software has been developed and validated. Optimum settings for detection parameters such as spectral match threshold and first

  20. ESO 243-49 HLX-1: scaling of X-ray spectral properties and black hole mass determination

    CERN Document Server

    Titarchuk, Lev

    2016-01-01

    We report the results of Swift/XRT observations (2008-2015) of a hyper-luminous X-ray source, ESO 243-49 HLX-1. We found a strong observational evidence that ESO 243-49 HLX-1 underwent spectral transitions from the low/hard state to the high/soft state during these observations. The spectra of ESO 243-49 HLX-1 are well fitted by the so-{called} bulk motion Comptonization model for all spectral states. We have established the photon index Gamma saturation level, Gamma_{sat}$=3.0+/-0.1, in the correlation of Gamma versus mass accretion rate dot M. This Gamma-dot M correlation allows us to estimate the black hole (BH) mass in ESO 243-49 HLX-1 to be M_{BH}~ 7x 10^4 solar masses, assuming the distance to ESO 243-49 of 95 Mpc. For the BH mass estimate we used the scaling method, taking Galactic BHs XTE~J1550-564, H~1743-322 and 4U~1630-472, and an extragalactic BH source, M101 ULX-1 as reference sources. The Gamma-dot M correlation revealed in ESO 243-49 HLX-1 is similar to those in a number of Galactic and extraga...

  1. AS ABOVE, SO BELOW: EXPLOITING MASS SCALING IN BLACK HOLE ACCRETION TO BREAK DEGENERACIES IN SPECTRAL INTERPRETATION

    Energy Technology Data Exchange (ETDEWEB)

    Markoff, Sera; Silva, Catia V. [Anton Pannekoek Institute for Astronomy, University of Amsterdam, 1098 XH Amsterdam (Netherlands); Nowak, Michael A. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics, Cambridge, MA 02139 (United States); Gallo, Elena; Plotkin, Richard M. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109-1042 (United States); Hynes, Robert [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001 (United States); Wilms, Jörn [Dr. Karl Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, D-96049 Bamberg (Germany); Maitra, Dipankar [Department of Physics and Astronomy, Wheaton College, Norton, MA 02766 (United States); Drappeau, Samia, E-mail: S.B.Markoff@uva.nl, E-mail: C.V.DeJesusSilva@uva.nl, E-mail: mnowak@space.mit.edu, E-mail: egallo@umich.edu, E-mail: rih@redstick.phys.lsu.edu, E-mail: joern.wilms@sternwarte.uni-erlangen.de, E-mail: maitra_dipankar@wheatoncollege.edu, E-mail: samia.drappeau@irap.omp.eu [CNRS, IRAP, BP 44346, F-31028 Toulouse cedex 4 (France)

    2015-10-20

    Over the past decade, evidence has mounted that several aspects of black hole (BH) accretion physics proceed in a mass-invariant way. One of the best examples of this scaling is the empirical “fundamental plane of BH accretion” relation linking mass, radio, and X-ray luminosity over eight orders of magnitude in BH mass. The currently favored theoretical interpretation of this relation is that the physics governing power output in weakly accreting BHs depends more on relative accretion rate than on mass. In order to test this theory, we explore whether a mass-invariant approach can simultaneously explain the broadband spectral energy distributions from two BHs at opposite ends of the mass scale but that are at similar Eddington accretion fractions. We find that the same model, with the same value of several fitted physical parameters expressed in mass-scaling units to enforce self-similarity, can provide a good description of two data sets from V404 Cyg and M81*, a stellar and supermassive BH, respectively. Furthermore, only one of several potential emission scenarios for the X-ray band is successful, suggesting it is the dominant process driving the fundamental plane relation at this accretion rate. This approach thus holds promise for breaking current degeneracies in the interpretation of BH high-energy spectra and for constructing better prescriptions of BH accretion for use in various local and cosmological feedback applications.

  2. As above, so below: exploiting mass scaling in black hole accretion to break degeneracies in spectral interpretation

    CERN Document Server

    Markoff, Sera; Gallo, Elena; Hynes, Robert; Wilms, Jörn; Plotkin, Richard M; Maitra, Dipankar; Silva, Catia V; Drappeau, Samia

    2015-01-01

    Over the last decade, the evidence is mounting that several aspects of black hole accretion physics proceed in a mass-invariant way. One of the best examples of this scaling is the empirical "Fundamental Plane of Black Hole Accretion" relation linking mass, radio and X-ray luminosity over eight orders of magnitude in black hole mass. The currently favored theoretical interpretation of this relation is that the physics governing power output in weakly accreting black holes depends more on relative accretion rate than on mass. In order to test this theory, we explore whether a mass-invariant approach can simultaneously explain the broadband spectral energy distributions from two black holes at opposite ends of the mass scale but at similar Eddington accretion fractions. We find that the same model, with the same value of several fitted physical parameters expressed in mass-scaling units to enforce self-similarity, can provide a good description of two datasets from V404 Cyg and M81*, a stellar and supermassive ...

  3. Potential of VIS-NIR-SWIR Spectroscopy from the Chinese Soil Spectral Library for Assessment of Nitrogen Fertilization Rates in the Paddy-Rice Region, China

    Directory of Open Access Journals (Sweden)

    Shuo Li

    2015-05-01

    Full Text Available To meet growing food demand with limited land and reduced environmental impact, soil testing and formulated fertilization methods have been widely adopted around the world. However, conventional technology for investigating nitrogen fertilization rates (NFR is time consuming and expensive. Here, we evaluated the use of visible near-infrared shortwave-infrared (VIS-NIR-SWIR: 400–2500 nm spectroscopy for the assessment of NFR to provide necessary information for fast, cost-effective and precise fertilization rating. Over 2000 samples were collected from paddy-rice fields in 10 Chinese provinces; samples were added to the Chinese Soil Spectral Library (CSSL. Two kinds of modeling strategies for NFR, quantitative estimation of soil N prior to classification and qualitative by classification, were employed using partial least squares regression (PLSR, locally weighted regression (LWR, and support vector machine discriminant analogy (SVMDA. Overall, both LWR and SVMDA had moderate accuracies with Cohen’s kappa coefficients of 0.47 and 0.48, respectively, while PLSR had fair accuracy (0.37. We conclude that VIS-NIR-SWIR spectroscopy coupled with the CSSL appears to be a viable, rapid means for the assessment of NFR in paddy-rice soil. Based on qualitative classification of soil spectral data only, it is recommended that the SVMDA be adopted for rapid implementation.

  4. An open-source library for the numerical modeling of mass-transfer in solid oxide fuel cells

    Science.gov (United States)

    Novaresio, Valerio; García-Camprubí, María; Izquierdo, Salvador; Asinari, Pietro; Fueyo, Norberto

    2012-01-01

    The generation of direct current electricity using solid oxide fuel cells (SOFCs) involves several interplaying transport phenomena. Their simulation is crucial for the design and optimization of reliable and competitive equipment, and for the eventual market deployment of this technology. An open-source library for the computational modeling of mass-transport phenomena in SOFCs is presented in this article. It includes several multicomponent mass-transport models ( i.e. Fickian, Stefan-Maxwell and Dusty Gas Model), which can be applied both within porous media and in porosity-free domains, and several diffusivity models for gases. The library has been developed for its use with OpenFOAM ®, a widespread open-source code for fluid and continuum mechanics. The library can be used to model any fluid flow configuration involving multicomponent transport phenomena and it is validated in this paper against the analytical solution of one-dimensional test cases. In addition, it is applied for the simulation of a real SOFC and further validated using experimental data. Program summaryProgram title: multiSpeciesTransportModels Catalogue identifier: AEKB_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKB_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License No. of lines in distributed program, including test data, etc.: 18 140 No. of bytes in distributed program, including test data, etc.: 64 285 Distribution format: tar.gz Programming language:: C++ Computer: Any x86 (the instructions reported in the paper consider only the 64 bit case for the sake of simplicity) Operating system: Generic Linux (the instructions reported in the paper consider only the open-source Ubuntu distribution for the sake of simplicity) Classification: 12 External routines: OpenFOAM® (version 1.6-ext) ( http://www.extend-project.de) Nature of problem: This software provides a library of models for

  5. Marketing library and information services: international perspectives (Gupta; Konntz; Massísimo; Savard)

    OpenAIRE

    Fernández Marcial, Viviana

    2007-01-01

    This article reviews different experiences in library marketing developed around the world. It focuses on the marketing mix, the central element of a plan of marketing in which four aspects are defined, the four "p": the product, price, place and promotion.

  6. Marketing library and information services: international perspectives (Gupta; Konntz; Massísimo; Savard)

    OpenAIRE

    Fernández Marcial, Viviana

    2007-01-01

    This article reviews different experiences in library marketing developed around the world. It focuses on the marketing mix, the central element of a plan of marketing in which four aspects are defined, the four "p": the product, price, place and promotion.

  7. Historical Work in Mass Communication Studies: Literacy, Libraries, and Popular Reading.

    Science.gov (United States)

    Inglesby, Pamela

    Recent work in both the history of education and the influence of popular culture suggests that libraries can be studied as sites where the public is taught--through a variety of mechanisms--important lessons about communication, knowledge and society. Researchers have addressed the interpretive question of whether literacy is tied to progress and…

  8. Single particle mass spectral signatures from vehicle exhaust particles and the source apportionment of on-line PM2.5 by single particle aerosol mass spectrometry.

    Science.gov (United States)

    Yang, Jian; Ma, Shexia; Gao, Bo; Li, Xiaoying; Zhang, Yanjun; Cai, Jing; Li, Mei; Yao, Ling'ai; Huang, Bo; Zheng, Mei

    2017-09-01

    In order to accurately apportion the many distinct types of individual particles observed, it is necessary to characterize fingerprints of individual particles emitted directly from known sources. In this study, single particle mass spectral signatures from vehicle exhaust particles in a tunnel were performed. These data were used to evaluate particle signatures in a real-world PM2.5 apportionment study. The dominant chemical type originating from average positive and negative mass spectra for vehicle exhaust particles are EC species. Four distinct particle types describe the majority of particles emitted by vehicle exhaust particles in this tunnel. Each particle class is labeled according to the most significant chemical features in both average positive and negative mass spectral signatures, including ECOC, NaK, Metal and PAHs species. A single particle aerosol mass spectrometry (SPAMS) was also employed during the winter of 2013 in Guangzhou to determine both the size and chemical composition of individual atmospheric particles, with vacuum aerodynamic diameter (dva) in the size range of 0.2-2μm. A total of 487,570 particles were chemically analyzed with positive and negative ion mass spectra and a large set of single particle mass spectra was collected and analyzed in order to identify the speciation. According to the typical tracer ions from different source types and classification by the ART-2a algorithm which uses source fingerprints for apportioning ambient particles, the major sources of single particles were simulated. Coal combustion, vehicle exhaust, and secondary ion were the most abundant particle sources, contributing 28.5%, 17.8%, and 18.2%, respectively. The fraction with vehicle exhaust species particles decreased slightly with particle size in the condensation mode particles. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. The MUSCLES Treasury Survey: Temporally- and Spectrally-Resolved Irradiance from Low-mass Exoplanet Host Stars

    Science.gov (United States)

    France, Kevin; Parke Loyd, R. O.; Youngblood, Allison; Linsky, Jeffrey; MUSCLES Treasury Survey Team

    2016-01-01

    The spectral and temporal behavior of exoplanet host stars is a critical input to models of the chemistry and evolution of planetary atmospheres. High-energy photons (X-ray to near-UV; 5 - 3200 Ang) from these stars regulate the atmospheric temperature profiles and photochemistry on orbiting planets, influencing the production of potential "biomarker" gases. It has been shown that the atmospheric signatures of potentially habitable planets around low-mass stars may be significantly different from planets orbiting Sun-like stars owing to the different UV spectral energy distribution. I will present results from a panchromatic survey (Hubble/Chandra/XMM/optical) of M and K dwarf exoplanet hosts, the MUSCLES Treasury Survey (Measurements of the Ultraviolet Spectral Characteristics of Low-mass Exoplanetary Systems). We reconstruct the Lyman-alpha and extreme-UV (100-900 Ang) radiation lost to interstellar attenuation and create 5 Angstrom to 5 micron stellar irradiance spectra; these data will be publically available as a High-Level Science Product on MAST. We find that all low-mass exoplanet host stars exhibit significant chromospheric/transition region/coronal emission -- no "UV inactive" M dwarfs are observed. The F(far-UV)/F(near-UV) flux ratio, a driver for possible abiotic production of the suggested biomarkers O2 and O3, increases by ~3 orders of magnitude as the habitable zone moves inward from 1 to 0.1 AU, while the incident far-UV (912 - 1700 Ang) and XUV (5 - 900 Ang) radiation field strengths decrease by factors of a few across this range. Far-UV flare activity is common in 'optically inactive' M dwarfs; statistics from the entire sample indicate that large UV flares (E(300 - 1700 Ang) >= 10^31 erg) occur several times per day on typical M dwarf exoplanet hosts.

  10. Ub-library of Atomic Masses and Nuclear Ground States Deformations (CENPL.AMD)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The atomic mass is one of basic data of a nuclear. There are the atomic masses in all nuclear reaction model formulas and motion equations. For any reaction calculations atomic masses are basic data for getting binding energies or Q-values. In some applications, it is important also to have atomic masses even for exotic nuclei quite far from the valley of stability. In addition, nuclear ground state deformations and abundance values are also requisite in the nuclear data calculations. For this purpose, A data file on atomic masses and nuclear ground states deformations (AMD) were constructed, which

  11. Electron ionization mass spectral study of selected N-amide and N-alkyl derivatives of cytisine.

    Science.gov (United States)

    Przybył, Anna K; Prukała, Wiesław; Kikut-Liga, Dariusz

    2007-01-01

    (-)-Cytisine and its derivatives are promising alkaloids in the development of new drugs for the treatment of disorders of the central nervous system (CNS). Electron ionization (EI) mass spectral fragmentations of cytisine (1), N-methylcytisine (2), N-ethylcytisine (3), N-acetylcytisine (4), N-propionylcytisine (5) and N-benzoylcytisine (6) have been investigated. Detailed fragmentation pathways have been identified for all significant ions, including a few characteristic fragment ions. The principal fragmentation routes of compounds 1-6 have been determined on the basis of EI low-resolution, high-resolution and B2/E linked scans as well as linked scans at constant B/E.

  12. Calculation of the information content of retrieval procedures applied to mass spectral data bases

    NARCIS (Netherlands)

    Marlen, G. van; Dijkstra, Auke; Klooster, H.A. van 't

    1979-01-01

    A procedure has been developed for estimating the information content of retrieval systems with binary-coded mass spectra, as well as mass spectra coded by other methods, from the statistical properties of a reference file. For a reference file, binary-coded with a threshold of 1% of the intensity o

  13. Further Defining Spectral Type "Y" and Exploring the Low-mass End of the Field Brown Dwarf Mass Function

    CERN Document Server

    Kirkpatrick, J Davy; Cushing, Michael C; Mace, Gregory N; Griffith, Roger L; Skrutskie, Michael F; Marsh, Kenneth A; Wright, Edward L; Eisenhardt, Peter R; McLean, Ian S; Mainzer, Amanda K; Burgasser, Adam J; Tinney, C G; Parker, Stephen; Salter, Graeme

    2012-01-01

    We present the discovery of another seven Y dwarfs from the Wide-field Infrared Survey Explorer (WISE). Using these objects, as well as the first six WISE Y dwarf discoveries from Cushing et al., we further explore the transition between spectral types T and Y. We find that the T/Y boundary roughly coincides with the spot where the J-H colors of brown dwarfs, as predicted by models, turn back to the red. Moreover, we use preliminary trigonometric parallax measurements to show that the T/Y boundary may also correspond to the point at which the absolute H (1.6 um) and W2 (4.6 um) magnitudes plummet. We use these discoveries and their preliminary distances to place them in the larger context of the Solar Neighborhood. We present a table that updates the entire stellar and substellar constituency within 8 parsecs of the Sun, and we show that the current census has hydrogen-burning stars outnumbering brown dwarfs by roughly a factor of six. This factor will decrease with time as more brown dwarfs are identified wi...

  14. Electrospray ionization mass spectral characteristics and fragmentation mechanisms of Angiotensin II and its analogues

    Science.gov (United States)

    Li, Huihui; Yuan, Gu

    2006-05-01

    The characteristic fragmentation pathways of Angiotensin II and eight analogues were investigated by electrospray ionization tandem mass spectrometry. The main fragmentations involve the cleavages of the CCO and CONH bonds with the loss of water, ammonia or carbon monoxide and rearrangements involving hydrogen atoms, and the MS/MS spectra give significant sequence information of these octapeptides. In addition, the two members of the analogues with the same mass and different elemental composition can be distinguished by the MS/MS spectra of [M + H]+ and fragment ions. These results show that ESI tandem mass spectrometry is an excellent tool for the structural identification of Angiotensin II and its analogues.

  15. Synthetic observations of first hydrostatic cores in collapsing low-mass dense cores. I. Spectral energy distributions and evolutionary sequence

    CERN Document Server

    Commercon, Benoit; Dullemond, Cornelis P; Henning, Thomas

    2012-01-01

    The low-mass star formation evolutionary sequence is relatively well-defined both from observations and theoretical considerations. The first hydrostatic core is the first protostellar equilibrium object that is formed during the star formation process. Using state-of-the-art radiation-magneto-hydrodynamic 3D adaptive mesh refinement calculations, we aim to provide predictions for the dust continuum emission from first hydrostatic cores. We investigate the collapse and the fragmentation of magnetized one solar mass prestellar dense cores and the formation and evolution of first hydrostatic cores using the RAMSES code. We use three different magnetization levels for the initial conditions, which cover a large variety of early evolutionary morphology, e.g., the formation of a disk or a pseudo-disk, outflow launching, and fragmentation. We post-process the dynamical calculations using the 3D radiative transfer code RADMC-3D. We compute spectral energy distributions and usual evolutionary stage indicators such as...

  16. ProMEX – a mass spectral reference database for Plant Proteomics

    Directory of Open Access Journals (Sweden)

    Stefanie eWienkoop

    2012-06-01

    Full Text Available The ProMEX database is one of the main collection of annotated tryptic peptides in plant proteomics. The main objective of the ProMEX Database is to provide experimental MS/MS-based information for cell type-specific or subcellular proteomes in Arabidopsis thaliana, Medicago truncatula, Chlamydomonas reinhardtii, Lotus japonicus, Lotus corniculatus, Phaseolus vulgaris, Lycopersicon esculentum, Solanum tuberosum, Nicotiana tabacum, Glycine max, Zea mays, Bradyrhizobium japonicum and Sinorhizobium meliloti. Direct links at the protein level to the most relevant databases are present in ProMEX. Furthermore, the spectral sequence information are linked to their respective pathways and can be viewed in pathway maps.

  17. ESO 243-49 HLX-1: scaling of X-ray spectral properties and black hole mass determination

    Science.gov (United States)

    Titarchuk, Lev; Seifina, Elena

    2016-11-01

    We report the results of Swift/XRT observations (2008-2015) of a hyper-luminous X-ray source, ESO 243-49 HLX-1. We demonstrate a strong observational evidence that ESO 243-49 HLX-1 undergoes spectral transitions from the low/hard state to the high/soft state during these observations. The spectra of ESO 243-49 HLX-1 are well fitted by the so-called bulk motion Comptonization model for all spectral states. We have established the photon index (Γ) saturation level, Γsat = 3.0 ± 0.1, in the Γ versus mass accretion rate (Ṁ) correlation. This Γ-Ṁ correlation allows us to estimate black hole (BH) mass in ESO 243-49 HLX-1 to be MBH 7 × 104 M⊙ assuming the distance to ESO 243-49 of 95 Mpc. For the BH mass estimate we use the scaling method taking Galactic BHs XTE J1550-564, H 1743-322 and 4U 1630-472, and an extragalactic BH source, M101 ULX-1 as reference sources. The Γ versus Ṁ correlation revealed in ESO 243-49 HLX-1 is similar to those in a number of Galactic and extragalactic BHs and it clearly shows the correlation along with the strong Γ saturation at ≈3. This is a robust observational evidence for the presence of a BH in ESO 243-49 HLX-1. We also find that the seed (disk) photon temperatures are quite low, of order of 50-140 eV which are consistent with high BH mass in ESO 243-49 HLX-1.

  18. X-ray dual energy spectral parameter optimization for bone Calcium/Phosphorus mass ratio estimation

    Science.gov (United States)

    Sotiropoulou, P. I.; Fountos, G. P.; Martini, N. D.; Koukou, V. N.; Michail, C. M.; Valais, I. G.; Kandarakis, I. S.; Nikiforidis, G. C.

    2015-09-01

    Calcium (Ca) and Phosphorus (P) bone mass ratio has been identified as an important, yet underutilized, risk factor in osteoporosis diagnosis. The purpose of this simulation study is to investigate the use of effective or mean mass attenuation coefficient in Ca/P mass ratio estimation with the use of a dual-energy method. The investigation was based on the minimization of the accuracy of Ca/P ratio, with respect to the Coefficient of Variation of the ratio. Different set-ups were examined, based on the K-edge filtering technique and single X-ray exposure. The modified X-ray output was attenuated by various Ca/P mass ratios resulting in nine calibration points, while keeping constant the total bone thickness. The simulated data were obtained considering a photon counting energy discriminating detector. The standard deviation of the residuals was used to compare and evaluate the accuracy between the different dual energy set-ups. The optimum mass attenuation coefficient for the Ca/P mass ratio estimation was the effective coefficient in all the examined set-ups. The variation of the residuals between the different set-ups was not significant.

  19. Synthetic observations of first hydrostatic cores in collapsing low-mass dense cores. I. Spectral energy distributions and evolutionary sequence

    Science.gov (United States)

    Commerçon, B.; Launhardt, R.; Dullemond, C.; Henning, Th.

    2012-09-01

    Context. The low-mass star formation evolutionary sequence is relatively well-defined both from observations and theoretical considerations. The first hydrostatic core is the first protostellar equilibrium object that is formed during the star formation process. Aims: Using state-of-the-art radiation-magneto-hydrodynamic 3D adaptive mesh refinement calculations, we aim to provide predictions for the dust continuum emission from first hydrostatic cores. Methods: We investigated the collapse and the fragmentation of magnetized 1 M⊙ prestellar dense cores and the formation and evolution of first hydrostatic cores using the RAMSES code. We used three different magnetization levels for the initial conditions, which cover a wide variety of early evolutionary morphology, e.g., the formation of a disk or a pseudo-disk, outflow launching, and fragmentation. We post-processed the dynamical calculations using the 3D radiative transfer code RADMC-3D. We computed spectral energy distributions and usual evolutionary stage indicators such as bolometric luminosity and temperature. Results: We find that the first hydrostatic core lifetimes depend strongly on the initial magnetization level of the parent dense core. We derive, for the first time, spectral energy distribution evolutionary sequences from high-resolution radiation-magneto-hydrodynamic calculations. We show that under certain conditions, first hydrostatic cores can be identified from dust continuum emission at 24 μm and 70 μm. We also show that single spectral energy distributions cannot help in distinguishing between the formation scenarios of the first hydrostatic core, i.e., between the magnetized and non-magnetized models. Conclusions: Spectral energy distributions are a first useful and direct way to target first hydrostatic core candidates but high-resolution interferometry is definitively needed to determine the evolutionary stage of the observed sources.

  20. Morpheus Spectral Counter: A computational tool for label-free quantitative mass spectrometry using the Morpheus search engine.

    Science.gov (United States)

    Gemperline, David C; Scalf, Mark; Smith, Lloyd M; Vierstra, Richard D

    2016-03-01

    Label-free quantitative MS based on the Normalized Spectral Abundance Factor (NSAF) has emerged as a straightforward and robust method to determine the relative abundance of individual proteins within complex mixtures. Here, we present Morpheus Spectral Counter (MSpC) as the first computational tool that directly calculates NSAF values from output obtained from Morpheus, a fast, open-source, peptide-MS/MS matching engine compatible with high-resolution accurate-mass instruments. NSAF has distinct advantages over other MS-based quantification methods, including a greater dynamic range as compared to isobaric tags, no requirement to align and re-extract MS1 peaks, and increased speed. MSpC features an easy-to-use graphic user interface that additionally calculates both distributed and unique NSAF values to permit analyses of both protein families and isoforms/proteoforms. MSpC determinations of protein concentration were linear over several orders of magnitude based on the analysis of several high-mass accuracy datasets either obtained from PRIDE or generated with total cell extracts spiked with purified Arabidopsis 20S proteasomes. The MSpC software was developed in C# and is open sourced under a permissive license with the code made available at http://dcgemperline.github.io/Morpheus_SpC/.

  1. Spectral-Timing Analysis of Kilohetrz Quasi-Periodic Osciallations in Neutron Star Low-Mass X-ray Binaries

    Science.gov (United States)

    Troyer, Jon; Peille, Philippe; Cackett, Edward; Barret, Didier

    2017-08-01

    Kilohertz quasi-periodic oscillations or kHz QPOs are intensity variations that occur in the X-ray band observed in neutron star low-mass X-ray binary (LMXB) systems. In such systems, matter is transferred from a secondary low-mass star to a neutron star via the process of accretion. kHz QPOs occur on the timescale of the inner accretion flow and may carry signatures of the physics of strong gravity (c2 ~ GM/R) and possibly clues to constraining the neutron star equation of state (EOS). Both the timing behavior of kHz QPOs and the time-averaged spectra of these systems have been studied extensively. No model derived from these techniques has been able to illuminate the origin of kHz QPOs. Spectral-timing is an analysis technique that can be used to derive information about the nature of physical processes occurring within the accretion flow on the timescale of the kHz QPO. To date, kHz QPOs of (4) neutron star LMXB systems have been studied with spectral-timing techniques. We present a comprehensive study of spectral-timing products of kHz QPOs from systems where data is available in the RXTE archive to demonstrate the promise of this technique to gain insights regarding the origin of kHz QPOs. Specifically, we show correlated time-lags as a function of QPO frequency and energy for the various LMXB systems where kHz QPOs are detected.

  2. Endmember identification from EO-1 Hyperion L1_R hyperspectral data to build saltmarsh spectral library in Hunter Wetland, NSW, Australia

    Science.gov (United States)

    Rasel, Sikdar M. M.; Chang, Hsing-Chung; Ralph, Tim; Saintilan, Neil

    2015-10-01

    Saltmarsh is one of the important communities of wetlands, however, due to a range of pressures, it has been declared as an EEC (Ecological Endangered Community) in Australia. In order to correctly identify different saltmarsh species, development of spectral libraries of saltmarsh species is essential to monitor this EEC. Hyperspectral remote sensing, can explore the area of wetland monitoring and mapping. The benefits of Hyperion data to wetland monitoring have been studied at Hunter Wetland Park, NSW, Australia. After exclusion of bad bands from the original data, an atmospheric correction model was applied to minimize atmospheric effect and to retrieve apparent surface reflectance for different land cover. Large data dimensionality was reduced by Forward Minimum Noise Fraction (MNF) algorithm. It was found that first 32 MNF band contains more than 80% information of the image. Pixel Purity Index (PPI) algorithm worked properly to extract pure pixel for water, builtup area and three vegetation Casuarina sp., Phragmitis sp. and green grass. The result showed it was challenging to extract extreme pure pixel for Sporobolus and Sarcocornia from the data due to coarse resolution (30 m) and small patch size (<3 m) of those vegetation on the ground . Spectral Angle Mapper, classified the image into five classes: Casuarina, Saltmarsh (Phragmitis), Green grass, Water and Builtup area with 43.55 % accuracy. This classification also failed to classify Sporobolus as a distinct group due to the same reason. A high spatial resolution airborne hyperspectral data and a new study site with a bigger patch of Sporobolus and Sarcocornia is proposed to overcome the issue.

  3. The yeast metabolome addressed by electrospray ionization mass spectrometry: Initiation of a mass spectral library and its applications for metabolic footprinting by direct infusion mass spectrometry

    DEFF Research Database (Denmark)

    Højer-Pedersen, Jesper Juul; Smedsgaard, Jørn; Nielsen, Jens

    2008-01-01

    into the ionization and fragmentation characteristics of the different metabolites. With this insight, a small study of metabolic footprinting with ESI-MS demonstrated that biological information can be extracted from footprinting spectra. Statistical analysis of the footprinting data revealed discriminating ions......, which could be assigned using the in silico metabolome. By this approach metabolic footprinting can advance from a classification method that is used to derive biological information based on guilt-by-association, to a tool for extraction of metabolic differences, which can guide new targeted biological...

  4. Spectral Energy Distributions and Masses of 304 M31 Old Star Clusters

    CERN Document Server

    Ma, Jun; Wu, Zhenyu; Zhang, Tianmeng; Zou, Hu; Nie, Jundan; Zhou, Zhiming; Zhou, Xu; Wu, Jianghua; Du, Cuihua; Yuan, Qirong

    2014-01-01

    This paper presents CCD multicolor photometry for 304 old star clusters in the nearby spiral galaxy M31. Of which photometry of 55 star clusters is first obtained. The observations were carried out as a part of the Beijing--Arizona--Taiwan--Connecticut (BATC) Multicolor Sky Survey from 1995 February to 2008 March, using 15 intermediate-band filters covering 3000--10000 \\AA. Detailed comparisons show that our photometry is in agreement with previous measurements. Based on the ages and metallicities from Caldwell et al. and the photometric measurements here, we estimated the clusters' masses by comparing their multicolor photometry with stellar population synthesis models. The results show that the sample clusters have masses between $\\sim 3\\times10^4 M_\\odot$ and $\\sim 10^7 M_\\odot$ with the peak of $\\sim 4\\times10^5 M_\\odot$. The masses here are in good agreement with those in previous studies. Combined with the masses of young star clusters of M31 from Wang et al., we find that the peak of mass of old cluste...

  5. Study of $\\tau$ decays involving kaons, spectral functions and determination of the strange quark mass

    CERN Document Server

    Barate, R; Ghez, P; Goy, C; Lees, J P; Merle, E; Minard, M N; Pietrzyk, B; Alemany, R; Casado, M P; Chmeissani, M; Crespo, J M; Fernández, E; Fernández-Bosman, M; Garrido, L; Graugès-Pous, E; Juste, A; Martínez, M; Merino, G; Miquel, R; Mir, L M; Pacheco, A; Park, I C; Riu, I; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Becker, U; Boix, G; Cattaneo, M; Ciulli, V; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Halley, A W; Hansen, J B; Harvey, J; Janot, P; Jost, B; Lehraus, Ivan; Leroy, O; Mato, P; Minten, Adolf G; Moutoussi, A; Ranjard, F; Rolandi, Luigi; Rousseau, D; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Teubert, F; Tomalin, I R; Tournefier, E; Ajaltouni, Ziad J; Badaud, F; Chazelle, G; Deschamps, O; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Blondel, A; Bonneaud, G R; Brient, J C; Rougé, A; Rumpf, M; Swynghedauw, M; Verderi, M; Videau, H L; Focardi, E; Parrini, G; Zachariadou, K; Cavanaugh, R J; Corden, M; Georgiopoulos, C H; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Cerutti, F; Chiarella, V; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Lynch, J G; Negus, P; O'Shea, V; Raine, C; Teixeira-Dias, P; Thompson, A S; Buchmüller, O L; Dhamotharan, S; Geweniger, C; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Marinelli, N; Sedgbeer, J K; Spagnolo, P; Thomson, E; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Buck, P G; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Robertson, N A; Williams, M; Giehl, I; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Wachsmuth, H W; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Carr, J; Coyle, P; Etienne, F; Ealet, A; Motsch, F; Payre, P; Talby, M; Thulasidas, M; Aleppo, M; Antonelli, M; Ragusa, F; Berlich, R; Büscher, V; Dietl, H; Ganis, G; Hüttmann, K; Lütjens, G; Mannert, C; Männer, W; Moser, H G; Schael, S; Settles, Ronald; Seywerd, H C J; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Schune, M H; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Bettarini, S; Boccali, T; Bozzi, C; Calderini, G; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Giassi, A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Rizzo, G; Sanguinetti, G; Sciabà, A; Sguazzoni, G; Tenchini, Roberto; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Chambers, J T; Cowan, G D; Green, M G; Medcalf, T; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Konstantinidis, N P; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Thompson, L F; Affholderbach, K; Böhrer, A; Brandt, S; Foss, J; Grupen, Claus; Prange, G; Smolik, L; Stephan, F; Giannini, G; Gobbo, B; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; Gao, Y; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; Mamier, G; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Vogt, M; Walsh, J; Wu Sau Lan; Wu, X; Zobernig, G

    1999-01-01

    All ALEPH measurements of branching ratios of tau decays involving kaons are summarized including a combination of results obtained with K^0_S and K^0_L detection. The decay dynamics are studied, leading to the determination of contributions from vector K^*(892) and K^{*}(1410), and axial-vector K_1(1270) and K_1(1400) resonances. Agreement with isospin symmetry is observed among the different final states. Under the hypothesis of the conserved vector current, the spectral function for the K\\bar{K}\\pi mode is compared with the corresponding cross section for low energy e^+e^- annihilation, yielding an axial-vector fraction of (94^{+6}_{-8})% for this mode. The branching ratio for tau decay into all strange final states is determined to be B(\\tau^-\\to X^-(S=-1)\

  6. Dereplication of Natural Products Using GC-TOF Mass Spectrometry: Improved Metabolite Identification by Spectral Deconvolution Ratio Analysis

    Science.gov (United States)

    Carnevale Neto, Fausto; Pilon, Alan C.; Selegato, Denise M.; Freire, Rafael T.; Gu, Haiwei; Raftery, Daniel; Lopes, Norberto P.; Castro-Gamboa, Ian

    2016-01-01

    Dereplication based on hyphenated techniques has been extensively applied in plant metabolomics, thereby avoiding re-isolation of known natural products. However, due to the complex nature of biological samples and their large concentration range, dereplication requires the use of chemometric tools to comprehensively extract information from the acquired data. In this work we developed a reliable GC-MS-based method for the identification of non-targeted plant metabolites by combining the Ratio Analysis of Mass Spectrometry deconvolution tool (RAMSY) with Automated Mass Spectral Deconvolution and Identification System software (AMDIS). Plants species from Solanaceae, Chrysobalanaceae and Euphorbiaceae were selected as model systems due to their molecular diversity, ethnopharmacological potential, and economical value. The samples were analyzed by GC-MS after methoximation and silylation reactions. Dereplication was initiated with the use of a factorial design of experiments to determine the best AMDIS configuration for each sample, considering linear retention indices and mass spectral data. A heuristic factor (CDF, compound detection factor) was developed and applied to the AMDIS results in order to decrease the false-positive rates. Despite the enhancement in deconvolution and peak identification, the empirical AMDIS method was not able to fully deconvolute all GC-peaks, leading to low MF values and/or missing metabolites. RAMSY was applied as a complementary deconvolution method to AMDIS to peaks exhibiting substantial overlap, resulting in recovery of low-intensity co-eluted ions. The results from this combination of optimized AMDIS with RAMSY attested to the ability of this approach as an improved dereplication method for complex biological samples such as plant extracts. PMID:27747213

  7. Dereplication of Natural Products Using GC-TOF Mass Spectrometry: Improved Metabolite Identification By Spectral Deconvolution Ratio Analysis

    Directory of Open Access Journals (Sweden)

    Fausto Carnevale Neto

    2016-09-01

    Full Text Available Dereplication based on hyphenated techniques has been extensively applied in plant metabolomics, avoiding re-isolation of known natural products. However, due to the complex nature of biological samples and their large concentration range, dereplication requires the use of chemometric tools to comprehensively extract information from the acquired data. In this work we developed a reliable GC-MS-based method for the identification of non-targeted plant metabolites by combining the Ratio Analysis of Mass Spectrometry deconvolution tool (RAMSY with Automated Mass Spectral Deconvolution and Identification System software (AMDIS. Plants species from Solanaceae, Chrysobalanaceae and Euphorbiaceae were selected as model systems due to their molecular diversity, ethnopharmacological potential and economical value. The samples were analyzed by GC-MS after methoximation and silylation reactions. Dereplication initiated with the use of a factorial design of experiments to determine the best AMDIS configuration for each sample, considering linear retention indices and mass spectral data. A heuristic factor (CDF, compound detection factor was developed and applied to the AMDIS results in order to decrease the false-positive rates. Despite the enhancement in deconvolution and peak identification, the empirical AMDIS method was not able to fully deconvolute all GC-peaks, leading to low MF values and/or missing metabolites. RAMSY was applied as a complementary deconvolution method to AMDIS to peaks exhibiting substantial overlap, resulting in recovery of low-intensity co-eluted ions. The results from this combination of optimized AMDIS with RAMSY attested to the ability of this approach as an improved dereplication method for complex biological samples such as plant extracts.

  8. Simultaneous determination of 40 novel psychoactive stimulants in urine by liquid chromatography-high resolution mass spectrometry and library matching.

    Science.gov (United States)

    Concheiro, Marta; Castaneto, Marisol; Kronstrand, Robert; Huestis, Marilyn A

    2015-06-05

    The emergence of novel psychoactive substances is an ongoing challenge for analytical toxicologists. Different analogs are continuously introduced in the market to circumvent legislation and to enhance their pharmacological activity. Although detection of drugs in blood indicates recent exposure and link intoxication to the causative agent, urine is still the most preferred testing matrix in clinical and forensic settings. We developed a method for the simultaneous quantification of 8 piperazines, 4 designer amphetamines and 28 synthetic cathinones and 4 metabolites, in urine by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS). Data were acquired in full scan and data dependent MS(2) mode. Compounds were quantified by precursor ion exact mass, and confirmed by product ion spectra library matching, taking into account product ions' exact mass and intensities. One-hundred μL urine was subjected to solid phase cation exchange extraction (SOLA SCX). The chromatographic reverse-phase separation was achieved with gradient mobile phase of 0.1% formic acid in water and in acetonitrile in 20 min. The assay was linear from 2.5 or 5 to 500 μg/L. Imprecision (n=15) was urine specimens (n=62) were analyzed with the method that provides a comprehensive confirmation for 40 new stimulant drugs with specificity and sensitivity.

  9. SPIDER VIII - constraints on the stellar initial mass function of early-type galaxies from a variety of spectral features

    Science.gov (United States)

    La Barbera, F.; Ferreras, I.; Vazdekis, A.; de la Rosa, I. G.; de Carvalho, R. R.; Trevisan, M.; Falcón-Barroso, J.; Ricciardelli, E.

    2013-08-01

    We perform a spectroscopic study to constrain the stellar initial mass function (IMF) by using a large sample of 24 781 early-type galaxies from the Sloan Digital Sky Survey-based Spheroids Panchromatic Investigation in Different Environmental Regions survey. Clear evidence is found of a trend between IMF and central velocity dispersion (σ0), evolving from a standard Kroupa/Chabrier IMF at σ0 ˜ 100 km s-1 towards a more bottom-heavy IMF with increasing σ0, becoming steeper than the Salpeter function at σ0 ≳ 220 km s-1. We analyse a variety of spectral indices, combining gravity-sensitive features, with age- and metallicity-sensitive indices, and we also consider the effect of non-solar abundance variations. The indices, corrected to solar scale by means of semi-empirical correlations, are fitted simultaneously with the (nearly solar-scaled) extended MILES (MIUSCAT) stellar population models. Similar conclusions are reached when analysing the spectra with a hybrid approach, combining constraints from direct spectral fitting in the optical with those from IMF-sensitive indices. Our analysis suggests that σ0, rather than [α/Fe], drives the variation of the IMF. Although our analysis cannot discriminate between a single power-law (unimodal) IMF and a low-mass (≲0.5 M⊙) tapered (bimodal) IMF, robust constraints can be inferred for the fraction in low-mass stars at birth. This fraction (by mass) is found to increase from ˜20 per cent at σ0 ˜ 100 km s-1, up to ˜80 per cent at σ0 ˜ 300 km s-1. However, additional constraints can be provided with stellar mass-to-light (M/L) ratios: unimodal models predict M/L significantly larger than dynamical M/L, across the whole σ0 range, whereas a bimodal IMF is compatible. Our results are robust against individual abundance variations. No significant variation is found in Na and Ca in addition to the expected change from the correlation between [α/Fe] and σ0.

  10. In Situ Measurements of Aerosol Mass Concentration and Spectral Absorption at Three Location in and Around Mexico City

    Science.gov (United States)

    Chaudhry, Z.; Martins, V.; Li, Z.

    2006-12-01

    As a result of population growth and increasing industrialization, air pollution in heavily populated urban areas is one of the central environmental problems of the century. As a part of the MILAGRO (Megacity Initiative: Local and Global Research Observations) study, Nuclepore filters were collected in two size ranges (PM10 and PM2.5) at 12 hour intervals at three location in Mexico during March, 2006. Sampling stations were located at the Instituto Mexicano del Petroleo (T0), at the Rancho La Bisnago in the State of Hidalgo (T2) and along the Gulf Coast in Tampico (Tam). Each filter was analyzed for mass concentration, aerosol scattering and absorption efficiencies. Mass concentrations at T0 ranged from 47 to 179 μg/m3 for PM10 with an average concentration of 96 μg/m3, and from 20 to 93 μg/m3 for PM2.5 with an average concentration of 41 μg/m3. Mass concentrations at T2 ranged from 12 to 154 μg/m3 for PM10 with an average concentration of 51 μg/m3, and from 7 to 50 μg/m3 for PM2.5 with an average concentration of 25 μg/m3. Mass concentrations at Tam ranged from 34 to 80 μg/m3 for PM10 with an average concentration of 52 μg/m3, and from 8 to 23 μg/m3 for PM2.5 with an average concentration of 13 μg/m3. While some of the extreme values are likely linked to local emissions, regional air pollution episodes also played important roles. Each of the sampling stations experienced a unique atmospheric condition. The site at T0 was influenced by urban air pollution and dust storms, the site at T2 was significantly less affected by air pollution but more affected by regional dust storms and local dust devils while Tam was influenced by air pollution, dust storms and the natural marine environment. The spectral mass absorption efficiency was measured from 350 to 2500 nm and shows large differences between the absorption properties of soil dust, black carbon, and organic aerosols. The strong spectral differences observed can be related to differences in

  11. Change in activity character of coronae of low-mass stars of various spectral types

    CERN Document Server

    Nizamov, B A; Livshits, M A

    2016-01-01

    We study the dependence of the coronal activity index on the star's rotation rate. This question was considered earlier for 824 late-type stars on the basis of a consolidated catalogue of the soft X-ray fluxes. We carry out a more refined analysis separately for G, K and M dwarfs. They distinctively exhibit two modes of activity. The first one is the saturation mode, it is characteristic of young stars and is practically not related to their rotation. The second one refers to the solar-type activity the level of which strongly depends on the rotation period. We show that the transition from one mode to another takes place at the rotation periods of 1.1, 3.3 and 7.2 days for the stars of spectral types G2, K4 and M3 respectively. In the light of the discovery of superflares on G and K stars on the Kepler spacecraft there arises a question of how these objects differ from other active late-type stars. We analyse the location of superflare stars relative to the stars observed by Kepler on the "amplitude of rotat...

  12. The X-ray Power Spectral Density Function and Black Hole Mass Estimate for the Seyfert AGN IC 4329a

    CERN Document Server

    Markowitz, A

    2009-01-01

    We present the X-ray broadband power spectral density function (PSD) of the X-ray-luminous Seyfert IC 4329a, constructed from light curves obtained via Rossi X-ray Timing Explorer monitoring and an XMM-Newton observation. Modeling the 3-10 keV PSD using a broken power-law PSD shape, a break in power-law slope is significantly detected at a temporal frequency of 2.5(+2.5,-1.7) * 10^-6 Hz, which corresponds to a PSD break time scale T_b of 4.6(+10.1,-2.3) days. Using the relation between T_b, black hole mass M_BH, and bolometric luminosity as quantified by McHardy and coworkers, we infer a black hole mass estimate of M_BH = 1.3(+1.0,-0.3) * 10^8 solar masses and an accretion rate relative to Eddington of 0.21(+0.06,-0.10) for this source. Our estimate of M_BH is consistent with other estimates, including that derived by the relation between M_BH and stellar velocity dispersion. We also present PSDs for the 10-20 and 20-40 keV bands; they lack sufficient temporal frequency coverage to reveal a significant break,...

  13. SPIDER VIII - Constraints on the Stellar Initial Mass Function of Early-type Galaxies from a Variety of Spectral Features

    CERN Document Server

    La Barbera, F; Vazdekis, A; de la Rosa, I G; de Carvalho, R R; Trevisan, M; Falcón-Barroso, J; Ricciardelli, E

    2013-01-01

    We perform a spectroscopic study to constrain the stellar Initial Mass Function (IMF) by using a large sample of 24,781 early-type galaxies from the SDSS-based SPIDER survey. Clear evidence is found of a trend between IMF and central velocity dispersion, sigma0, evolving from a standard Kroupa/Chabrier IMF at 100km/s towards a more bottom-heavy IMF with increasing sigma0, becoming steeper than the Salpeter function at sigma0>220km/s. We analyze a variety of spectral indices, corrected to solar scale by means of semi-empirical correlations, and fitted simultaneously with extended MILES (MIUSCAT) stellar population models. Our analysis suggests that sigma0, rather than [alpha/Fe], drives the IMF variation. Although our analysis cannot discriminate between a single power-law (unimodal) and a low-mass (<0.5MSun) tapered (bimodal) IMF, we can robustly constrain the fraction in low-mass stars at birth, that is found to increase from 20% at sigma0~100km/s, up to 80% at sigma0~300km/s. Additional constraints can b...

  14. Identification strategies for flame retardants employing time-of-flight mass spectrometric detectors along with spectral and spectra-less databases

    OpenAIRE

    Ionas, Alin C.; Gomez, Ana Ballesteros; Leonards, Pim E. G.; Covaci, Adrian

    2015-01-01

    Abstract: In the past, the preferred strategy for the identification of unknown compounds was to search in an appropriate mass spectral database for spectra obtained using either electron ionisation (GC-MS analyses) or collision-induced dissociation (LC-MS/MS analyses). Recently, an increase has been seen in the use of accurate mass instruments and spectra-less databases, based on monoisotopic accurate mass alone. In this article, we describe a systematic workflow for the screening and identi...

  15. Molecular Structural Studies of Captopril Drug, Using Thermal Analysis, mass Spectral Fragmentation and Semi- empirical MO- Calculations

    Directory of Open Access Journals (Sweden)

    H. M. Arafa

    2014-12-01

    Full Text Available In this work captopril an antihypertensive (KPL drug, was investigated using thermal analysis (TA measurements (TG-DTA in comparison with electron impact (EI mass spectral (MS fragmentation at 70 eV. Semi-empirical molecular (MO calculations, using PM3 method in the neutral and positively charged forms of the drug. These include molecular geometry, bond order, charge distribution, heats of formation and ionization energy. The behavior of the drug under drug TA decomposition, reveal a moderate stability up to 160Co before a completely decomposition in the range 160-240 Co. The initial decomposition is due to COOH + CH3 loss, followed by SH loss. On the other hand, the molecular ion can easily fragmented by CO2 loss followed by SH loss. This is the best-selected pathway comparable with decomposition using TA. MO-Calculation is used to declare these observations.

  16. Mass and UV-visible spectral fingerprints of dissolved organic matter: sources and reactivity

    Directory of Open Access Journals (Sweden)

    Heather Erin Reader

    2015-10-01

    Full Text Available Advanced analytical techniques have revealed a high degree of complexity in the chemical makeup of dissolved organic matter (DOM. This has opened the door for a deeper understanding of the role of DOM in the aquatic environment. However, the expense, analytical cost, and challenges related to interpretation of the large datasets generated by these methods limit their widespread application. Optical methods, such as absorption and fluorescence spectroscopy are relatively inexpensive and easy to implement, but lack the detailed information available in more advanced methods. We were able to directly link the analysis of absorption spectra to the mass spectra of DOM using an in-line detector system coupled to multivariate data analysis. Monthly samples were taken from three river mouths in Sweden for one year. One subset of samples was exposed to photochemical degradation and another subset was exposed to long-term (4 months biological degradation. A principle component analysis was performed on the coupled absorption-mass spectra data. Loading spectra for each principle component show distinct fingerprints for both reactivity (i.e. photochemical, biological degradation and source (i.e. catchment land cover, temperature, hydrology. The fingerprints reveal mass-to-charge values that contribute to optical signals and characteristics seen in past studies, and emphasise the difficulties in interpreting changes in bulk CDOM characteristics resulting from multiple catchment processes. The approach provides a potential simple method for using optical indicators as tracers for more complex chemical processes both with regards to source material for DOM and the past reactive processing of DOM.

  17. An evaluation of the spectral properties of nerve agents for laser ionization mass spectrometry.

    Science.gov (United States)

    Imasaka, Tomoko; Imasaka, Totaro

    2014-01-01

    Excitation energies, oscillator strengths, and vacuum-ultraviolet/deep-ultraviolet absorption spectra were calculated for nerve agents, such as sarin, soman, VX, tabun, mustard gas, and analogs. We used time-dependent density functional theory (TD-DFT) methods that included B3LYP combined with basis sets of cc-pVDZ and cc-pVTZ, and ωB97XD with cc-pVTZ. The vertical ionization energies were also calculated for these compounds, in order to collect additional information relative to the optimal pathways for multiphoton ionization in mass spectrometry.

  18. Mass Spectral Profile for Rapid Differentiating Beta-Lactams from Their Ring-Opened Impurities

    Directory of Open Access Journals (Sweden)

    Hecheng Wang

    2015-01-01

    Full Text Available High performance liquid chromatography tandem mass spectrometry (HPLC MS has been widely used for β-lactam antibiotics determination. However, its application to identify impurities of these frequently used drugs is not sufficient at present. In this job, characteristic profiles of the collision induced dissociation (CID spectra of both β-lactams and ring-opened β-lactams were extracted from the MS data of six β-lactam antibiotics and their forty-five impurities, and were confirmed by the MS data reported in the literature. These characteristics have been successfully applied to rapid differentiation of β-lactam and ring-opened β-lactam impurities in cefixime, cefdinir, and cefaclor. However, these characteristic profiles can only be obtained under low activating voltage. They did not display in the high energy activated CID spectra. Diagnostic fragmentations for determining the localization of double bond and substituents on the thiazine ring and the side chain were also observed. In addition, several characteristic fragmentations are hopeful to be used to differentiate the configurations of C-2 on the thiazine ring of ring-opened impurities, which is generally disadvantageous of mass spectrometry. Taken together, forty-five impurities were identified from the capsules of cefixime, cefdinir, and cefaclor.

  19. Mass Spectral Profile for Rapid Differentiating Beta-Lactams from Their Ring-Opened Impurities.

    Science.gov (United States)

    Wang, Hecheng; Huang, Haiwei; Cao, Jin; Chui, Dehua; Xiao, Shengyuan

    2015-01-01

    High performance liquid chromatography tandem mass spectrometry (HPLC MS) has been widely used for β-lactam antibiotics determination. However, its application to identify impurities of these frequently used drugs is not sufficient at present. In this job, characteristic profiles of the collision induced dissociation (CID) spectra of both β-lactams and ring-opened β-lactams were extracted from the MS data of six β-lactam antibiotics and their forty-five impurities, and were confirmed by the MS data reported in the literature. These characteristics have been successfully applied to rapid differentiation of β-lactam and ring-opened β-lactam impurities in cefixime, cefdinir, and cefaclor. However, these characteristic profiles can only be obtained under low activating voltage. They did not display in the high energy activated CID spectra. Diagnostic fragmentations for determining the localization of double bond and substituents on the thiazine ring and the side chain were also observed. In addition, several characteristic fragmentations are hopeful to be used to differentiate the configurations of C-2 on the thiazine ring of ring-opened impurities, which is generally disadvantageous of mass spectrometry. Taken together, forty-five impurities were identified from the capsules of cefixime, cefdinir, and cefaclor.

  20. Spectral investigations of 2,5-difluoroaniline by using mass, electronic absorption, NMR, and vibrational spectra

    Science.gov (United States)

    Kose, Etem; Karabacak, Mehmet; Bardak, Fehmi; Atac, Ahmet

    2016-11-01

    One of the most significant aromatic amines is aniline, a primary aromatic amine replacing one hydrogen atom of a benzene molecule with an amino group (NH2). This study reports experimental and theoretical investigation of 2,5-difluoroaniline molecule (2,5-DFA) by using mass, ultraviolet-visible (UV-vis), 1H and 13C nuclear magnetic resonance (NMR), Fourier transform infrared and Raman (FT-IR and FT-Raman) spectra, and supported with theoretical calculations. Mass spectrum (MS) of 2,5-DFA is presented with their stabilities. The UV-vis spectra of the molecule are recorded in the range of 190-400 nm in water and ethanol solvents. The 1H and 13C NMR chemical shifts are recorded in CDCl3 solution. The vibrational spectra are recorded in the region 4000-400 cm-1 (FT-IR) and 4000-10 cm-1 (FT-Raman), respectively. Theoretical studies are underpinned the experimental results as described below; 2,5-DFA molecule is optimized by using B3LYP/6-311++G(d,p) basis set. The mass spectrum is evaluated and possible fragmentations are proposed based on the stable structure. The electronic properties, such as excitation energies, oscillator strengths, wavelengths, frontier molecular orbitals (FMO), HOMO and LUMO energies, are determined by time-dependent density functional theory (TD-DFT). The electrostatic potential surface (ESPs), density of state (DOS) diagrams are also prepared and evaluated. In addition to these, reduced density gradient (RDG) analysis is performed, and thermodynamic features are carried out theoretically. The NMR spectra (1H and 13C) are calculated by using the gauge-invariant atomic orbital (GIAO) method. The vibrational spectra of 2,5-DFA molecule are obtained by using DFT/B3LYP method with 6-311++G(d,p) basis set. Fundamental vibrations are assigned based on the potential energy distribution (PED) of the vibrational modes. The nonlinear optical properties (NLO) are also investigated. The theoretical and experimental results give a detailed description of

  1. Genetic programming:  a novel method for the quantitative analysis of pyrolysis mass spectral data.

    Science.gov (United States)

    Gilbert, R J; Goodacre, R; Woodward, A M; Kell, D B

    1997-11-01

    A technique for the analysis of multivariate data by genetic programming (GP) is described, with particular reference to the quantitative analysis of orange juice adulteration data collected by pyrolysis mass spectrometry (PyMS). The dimensionality of the input space was reduced by ranking variables according to product moment correlation or mutual information with the outputs. The GP technique as described gives predictive errors equivalent to, if not better than, more widespread methods such as partial least squares and artificial neural networks but additionally can provide a means for easing the interpretation of the correlation between input and output variables. The described application demonstrates that by using the GP method for analyzing PyMS data the adulteration of orange juice with 10% sucrose solution can be quantified reliably over a 0-20% range with an RMS error in the estimate of ∼1%.

  2. FTIR, magnetic, mass spectral, XRD and thermal studies of metal chelates of tenoxicam

    Science.gov (United States)

    Zayed, M. A.; El-Dien, F. A. Nour; Mohamed, Gehad G.; El-Gamel, Nadia E. A.

    2007-09-01

    Metal chelates of anti-inflammatory drug, tenoxicam (Ten), are synthesized and characterized using elemental analyses, IR, solid reflectance, magnetic, mass spectra, thermal analyses (TGA and DTA) and X-ray powder diffraction techniques. The chelates are found to have the general formulae [M(H 2L) 2(H 2O) x] (A) 2· yH 2O (where H 2L = neutral Ten, A = Cl in case of Ni(II) and Co(II) or AcO in case of Cu(II) and Zn(II) ions, x = 0-2 and y = 0-2.5) and [M(H 2L) 3](A) z· yH 2O (A = SO 4 in case of Fe(II) ion ( z = 1) or Cl in case of Fe(III) ( z = 3) and y = 0-4). IR spectra reveal that Ten behaves as a neutral bidentate ligand coordinated to the metal ions through the pyridyl- N and carbonyl- O of the amide moiety. The solid reflectance spectra and magnetic moment measurements reveal that these chelates have tetrahedral, square planar and octahedral geometrical structures. Mass spectra are also used to confirm the proposed formulae and the possible fragments resulted from fragmentation of Ten and its Zn(II) and Cu(II) chelates are suggested. The thermal behaviour of the chelates (TG/DTG, DTA) are discussed in detailed manner and revealed that water molecules of crystallization together with anions are removed in the first and second steps while the Ten molecules are removed in the subsequent steps. Different thermodynamic parameters are evaluated and the relative thermal stabilities of the complexes are discussed. X-ray powder diffraction patterns are used to indicate the polymorphic form of Ten and if the complexes have molecular similarity with respect to type of coordination.

  3. Structure investigation, spectral, thermal, X-ray and mass characterization of piroxicam and its metal complexes

    Science.gov (United States)

    Zayed, M. A.; Nour El-Dien, F. A.; Mohamed, Gehad G.; El-Gamel, Nadia E. A.

    2004-10-01

    [M(H 2L) 2](A) 2. yH 2O (where H 2L: neutral piroxicam (Pir), A: Cl - in case of Ni(II) or acetate anion in case of Cu(II) and Zn(II) ions and y=0-2.5) and [M(H 2L) 3](A) z. yH 2O (A: SO 42- in case of Fe(II) ion ( z=1) or Cl - in case of Fe(III) ( z=3) and Co(II) ions ( z=2) and y=1-4) chelates are prepared and characterized using elemental analyses, IR, magnetic and electronic reflectance measurements, mass spectra and thermal analyses. IR spectra reveal that Pir behaves a neutral bidentate ligand coordinated to the metal ions through the pyridyl-N and carbonyl-O of the amide moiety. The reflectance and magnetic moment measurements reveal that these chelates have tetrahedral, square planar and octahedral geometrical structures. Mass spectra and thermal analyses are also used to confirm the proposed formulae and the possible fragments resulted from fragmentation of Pir and its chelates. The thermal behaviour of the chelates (TGA and DTA) are discussed in detail and the thermal stability of the anhydrous chelates follow the order Ni(II)≅Cu(II)

  4. Quark-antiquark composite systems:the Bethe--Salpeter equation in the spectral-integration technique in the case of the different quark masses

    CERN Document Server

    Anisovich, A V; Markov, V N; Matveev, M A; Sarantsev, A V

    2004-01-01

    The Bethe--Salpeter equations for the quark-antiquark composite systems with different quark masses, such as $q\\bar s$ (with $q=u$,$d$), $q\\bar Q$ and $s \\bar Q$ (with $Q=c$,$b$), are written in terms of spectral integrals. For the mesons characterized by the mass $M$, spin $J$ and radial quantum number $n$, the equations are presented for the $(n,M^2)$-trajectories with fixed $J$. In the spectral-integral technique one can use the energy-dependent forces and get beyond instantaneous approximation. The mixing between states with different quark spin $S$ and angular momentum $L$ are also discussed.

  5. Long-slit spectral observations and stellar mass-to-light ratio of spiral galaxy UGC11919

    CERN Document Server

    Saburova, A; Uklein, R; Katkov, I

    2015-01-01

    We performed the long-slit observations of spiral galaxy UGC11919 with the Russian 6-m telescope to study its kinematics and stellar population. The previous studies gave basis to suspect that this galaxy possesses a peculiarly low mass-to-light ratio $M/L_B$ of stellar population which could indicate the presence of bottom-light stellar initial mass function (IMF). The ratio $M/L_B$ estimated for different evolutionary models of stellar population using both the broad-band magnitudes and the detailed spectral data confirms this peculiarity if the disc inclination angle $i>30^o$, as it was obtained earlier from the optical photometry, in a good agreement with the HI data cube modelling. However the re-processing of HI data cube we carried out showed that it is compatible with much lower value $i=13^o$ corresponding to the "normal" ratio $M/L_B$, which does not need any peculiar stellar IMF. Stellar velocity dispersion measured at one disc radial scalelength from the center also better agrees with the low disc...

  6. Spectral signatures of dissipative standing shocks and mass outflow in presence of Comptonization around a black hole

    CERN Document Server

    Mondal, Santanu; Debnath, Dipak

    2014-01-01

    Accretion flows having positive specific energy are known to produce outflows and winds which escape to a large distance. According to Two Component Advective Flow (TCAF) model, centrifugal pressure dominated region of the flow just outside the black hole horizon, with or without shocks, acts as the base of this outflow. Electrons from this region are depleted due to the wind and consequently, energy transfer rate due to inverse Comptonization of low energy photons are affected. Specifically, it becomes easier to cool this region and emerging spectrum is softened. Our main goal is to show spectral softening due to mass outflow in presence of Compton cooling. To achieve this, we modify Rankine-Hugoniot relationships at the shock front when post-shock region suffers mass loss due to winds and energy loss due to inverse Comptonization. We solve two-temperature equations governing an accretion flow around a black hole which include Coulomb exchange between protons and electrons and other major radiative processes...

  7. Determination of Black Hole Mass in Cyg X-1 by Scaling of Spectral Index-QPO Frequency Correlation

    CERN Document Server

    Shaposhnikov, N; Shaposhnikov, Nickolai; Titarchuk, Lev

    2007-01-01

    It is well established that timing and spectral properties of Galactic Black Hole (BH) X-ray binaries (XRB) are strongly correlated. In particular, it has been shown that low frequency Quasi-Periodic Oscillation (QPO) frequency - photon index correlation curves have a specific pattern. In a number of sources the shape of the index-low frequency QPO correlations are self-similar with a position offset in the QPO frequency-Gamma plane. Titarchuk & Fiorito presented strong theoretical and observational arguments that the QPO frequency values in this QPO frequency-Gamma correlation should be inversely proportional to M_{BH}. A simple translation of the correlation for a given source along the frequency axis leads to the observed correlation for another source. As a result of this translation one can obtain a scaling factor which is simply a BH mass ratio for these particular sources. This property of the correlations offers a fundamentally new method for BH mass determination in XRBs. Here we use the observed...

  8. Relativistic spectral features from X-ray illuminated spots and the measure of the black hole mass in AGN

    CERN Document Server

    Dovciak, M; Guainazzi, M; Karas, V; Matt, G

    2004-01-01

    Narrow spectral features in the 5--6 keV range were recently discovered in the X-ray spectra of a few active galactic nuclei. We discuss the possibility that these features are due to localized spots which occur on the surface of an accretion disc following its illumination by flares. We present detailed line profiles as a function of orbital phase of the spot and its radial distance from a central black hole. Comparison of these computed profiles with observed features can help to estimate parameters of the system. In principle this method can provide a powerful tool to measure the mass of super-massive black holes in active galactic nuclei. By comparing our simulations with the Chandra and XMM-Newton results, we show, however, that spectra from present generation X-ray satellites are not of good enough quality to fully exploit the method and determine the black hole mass with sufficient accuracy. This task has to be deferred to future missions with high throughput and high energy resolution, such as Constel...

  9. Electron ionization mass spectral fragmentation study of sulfation derivatives of polychlorinated biphenyls

    Directory of Open Access Journals (Sweden)

    Robertson Larry W

    2009-03-01

    Full Text Available Abstract Background Polychlorinated biphenyls are persistent organic pollutants that can be metabolized via hydroxylated PCBs to PCB sulfate metabolites. The sensitive and selective analysis of PCB sulfate monoesters by gas chromatography-mass spectrometry (GC-MS requires their derivatization, for example, as PCB 2,2,2-trichloroethyl (TCE sulfate monoesters. To aid in the identification of unknown PCB sulfate metabolites isolated from biological samples, the electron impact MS fragmentation pathways of selected PCB TCE sulfate diesters were analyzed and compared to the fragmentation pathways of the corresponding methoxylated PCBs. Results The most abundant and characteristic fragment ions of PCB TCE sulfate diesters were formed by releasing CHCCl3, SO3, HCl2 and/or CCl3 from the TCE sulfate moiety and Cl2, HCl, ethyne and chloroethyne from an intermediate phenylcyclopentadienyl cation. The fragmentation pattern depended on the degree of chlorination and the position of the TCE sulfate moiety (i.e., ortho vs. meta/para to the second phenyl ring, but were independent of the chlorine substitution pattern. These fragmentation pathways are similar to the fragmentation pathways of structurally related methoxylated PCBs. Conclusion Knowledge of the fragmentation patterns of PCB TCE sulfate diesters will greatly aid in determining the position of sulfate moiety (ortho vs. meta/para of unknown PCB sulfate metabolites isolated from environmental or laboratory samples.

  10. Identification of filamentous fungi isolates by MALDI-TOF mass spectrometry: clinical evaluation of an extended reference spectra library.

    Science.gov (United States)

    Becker, Pierre T; de Bel, Annelies; Martiny, Delphine; Ranque, Stéphane; Piarroux, Renaud; Cassagne, Carole; Detandt, Monique; Hendrickx, Marijke

    2014-11-01

    The identification of filamentous fungi by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) relies mainly on a robust and extensive database of reference spectra. To this end, a large in-house library containing 760 strains and representing 472 species was built and evaluated on 390 clinical isolates by comparing MALDI-TOF MS with the classical identification method based on morphological observations. The use of MALDI-TOF MS resulted in the correct identification of 95.4% of the isolates at species level, without considering LogScore values. Taking into account the Brukers' cutoff value for reliability (LogScore >1.70), 85.6% of the isolates were correctly identified. For a number of isolates, microscopic identification was limited to the genus, resulting in only 61.5% of the isolates correctly identified at species level while the correctness reached 94.6% at genus level. Using this extended in-house database, MALDI-TOF MS thus appears superior to morphology in order to obtain a robust and accurate identification of filamentous fungi. A continuous extension of the library is however necessary to further improve its reliability. Indeed, 15 isolates were still not represented while an additional three isolates were not recognized, probably because of a lack of intraspecific variability of the corresponding species in the database. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Fast atom bombardment mass spectral analysis of three new oxidative products of primaquine

    Science.gov (United States)

    Sinha, Sukesh N.; Dua, V. K.

    2004-03-01

    FAB mass spectrum of 5,5-di-[6-methoxy-8-(4'-amino-1'butyl amino)] quinoline (PI) was recorded in three different concentrations to establish the structure of new oxidative products of primaquine and also the effect of matrix on percentage relative abundance of molecular as well as fragment ions which were demonstrated first time. At three concentrations, three different behaviors of matrix, molecular and fragment ions were observed. At higher concentration (>1 nM) molecular ion behaved as a base peak, but due to side reaction with matrix certain extra peak were also obtained. Thus, the higher concentration was interesting to show the side reaction of analyte with m-nitro-benzyl alcohol (NBA) but not for molecular weight determination. At the lowest concentration (NBA as a matrix was recorded in between 0.6 and 1 nM concentrations for the structural elucidation of new compounds. Molecular ions and fragment ions of 5,5-di-[6-methoxy-8-(4'-amino-1' butyl amino)] quinoline (PI), 6-methoxy-5,8-di-[4'amino-1'-methyl butyl amino] quinoline (PII), and 5,5-di-[7-hydroxy-6-methoxy-8(4'-amino-1'-methyl butyl amino)] quinoline (PIII) were identified. The fragment ions were obtained due to ring cleavages, Retero-Diels-Alder reaction (RDA), loss of side chain, proton transfer and substituted groups of the ring. On the basis of the fragmentation schemes and molecular ion peaks the structure of three new compounds PI, PII and PIII were proposed. In vitro studies showed that the compounds PI and PII had four times more gametocytocidal activity than primaquine but the compound 6-methoxy-5,8-di-[4'-amino-1'-methyl butyl amino] quinoline (PII) was found to have good gametocytocidal activity against Plasmodium yoelli infected mice at 10 mg kg-1 dose in vivo. Therefore, the spectra reported might serve as reference for the development of new molecules for the radical cure of relapsing malaria.

  12. Integration of Stable Isotope and other Mass Spectral Data for Microbial Forensics

    Science.gov (United States)

    Kreuzer-Martin, H. W.; Jarman, K. H.

    2008-12-01

    The nascent field of microbial forensics requires the development of diverse signatures as indicators of various aspects of the production environment of microorganisms. We have characterized isotopic relationships between Bacillus subtilis ATCC 6051 spores and their growth environment, using as a database the carbon, nitrogen, oxygen and hydrogen stable isotope ratios of a total of 247 separate cultures of spores produced on a total of 32 different culture media. We have analyzed variation within individual samples, between cultures produced in tandem, and between cultures produced in the same medium but at different times in the context of using stable isotope ratios as a signature for sample matching. We have correlated the stable isotope ratios of carbon, nitrogen, oxygen, and hydrogen of growth medium nutrients or water and spores and show examples of how these relationships can be used to exclude nutrient or water samples as possible growth substrates for specific cultures. The power of stable isotope ratio data can be greatly enhanced by combining it with orthogonal datasets that speak to different aspects of an organism's production environment. We developed a Bayesian network that follows the causal relationship from culture medium recipe to spore elemental content as measured by secondary ion mass spectrometry (SIMS), carbon and nitrogen stable isotope ratios, and to the presence of residual agar by electrospray ionization MS (ESI-MS). The network was developed and tested on data from three replicate cultures of B. subtilis ATCC 49760 in broth and agar-containing versions of four different nutrient media. To test the network, data from SIMS analyses of B. subtilis 49760 produced in a different medium, from approximately 200 ESI MS analyses of B. thuringensis ATCC 58890 and B. anthracis Sterne grown in five additional media, and the stable isotope data from the 247 cultures of B. subtilis 6051 spores were used. This network was able to characterize

  13. Galaxy And Mass Assembly: the evolution of the cosmic spectral energy distribution from z = 1 to z = 0

    Science.gov (United States)

    Andrews, S. K.; Driver, S. P.; Davies, L. J. M.; Kafle, P. R.; Robotham, A. S. G.; Vinsen, K.; Wright, A. H.; Bland-Hawthorn, J.; Bourne, N.; Bremer, M.; da Cunha, E.; Drinkwater, M.; Holwerda, B.; Hopkins, A. M.; Kelvin, L. S.; Loveday, J.; Phillipps, S.; Wilkins, S.

    2017-09-01

    We present the evolution of the cosmic spectral energy distribution (CSED) from z = 1 to 0. Our CSEDs originate from stacking individual spectral energy distribution (SED) fits based on panchromatic photometry from the Galaxy And Mass Assembly (GAMA) and COSMOS data sets in 10 redshift intervals with completeness corrections applied. Below z = 0.45, we have credible SED fits from 100 nm to 1 mm. Due to the relatively low sensitivity of the far-infrared data, our far-infrared CSEDs contain a mix of predicted and measured fluxes above z = 0.45. Our results include appropriate errors to highlight the impact of these corrections. We show that the bolometric energy output of the Universe has declined by a factor of roughly 4 - from 5.1 ± 1.0 at z ∼ 1 to 1.3 ± 0.3 × 1035 h70 W Mpc-3 at the current epoch. We show that this decrease is robust to cosmic sample variance, the SED modelling and other various types of error. Our CSEDs are also consistent with an increase in the mean age of stellar populations. We also show that dust attenuation has decreased over the same period, with the photon escape fraction at 150 nm increasing from 16 ± 3 at z ∼ 1 to 24 ± 5 per cent at the current epoch, equivalent to a decrease in AFUV of 0.4 mag. Our CSEDs account for 68 ± 12 and 61 ± 13 per cent of the cosmic optical and infrared backgrounds, respectively, as defined from integrated galaxy counts and are consistent with previous estimates of the cosmic infrared background with redshift.

  14. FURTHER DEFINING SPECTRAL TYPE 'Y' AND EXPLORING THE LOW-MASS END OF THE FIELD BROWN DWARF MASS FUNCTION

    Energy Technology Data Exchange (ETDEWEB)

    Davy Kirkpatrick, J.; Gelino, Christopher R.; Griffith, Roger L.; Marsh, Kenneth A. [Infrared Processing and Analysis Center, MS 100-22, California Institute of Technology, Pasadena, CA 91125 (United States); Cushing, Michael C. [Department of Physics and Astronomy, MS 111, University of Toledo, 2801 W. Bancroft St., Toledo, OH 43606-3328 (United States); Mace, Gregory N.; Wright, Edward L.; McLean, Ian S. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States); Skrutskie, Michael F. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Eisenhardt, Peter R.; Mainzer, Amanda K. [NASA Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Burgasser, Adam J. [Department of Physics, University of California, San Diego, CA 92093 (United States); Tinney, C. G.; Parker, Stephen; Salter, Graeme, E-mail: davy@ipac.caltech.edu [Department of Astrophysics, School of Physics, University of New South Wales, NSW 2052 (Australia)

    2012-07-10

    We present the discovery of another seven Y dwarfs from the Wide-field Infrared Survey Explorer (WISE). Using these objects, as well as the first six WISE Y dwarf discoveries from Cushing et al., we further explore the transition between spectral types T and Y. We find that the T/Y boundary roughly coincides with the spot where the J - H colors of brown dwarfs, as predicted by models, turn back to the red. Moreover, we use preliminary trigonometric parallax measurements to show that the T/Y boundary may also correspond to the point at which the absolute H (1.6 {mu}m) and W2 (4.6 {mu}m) magnitudes plummet. We use these discoveries and their preliminary distances to place them in the larger context of the solar neighborhood. We present a table that updates the entire stellar and substellar constituency within 8 pc of the Sun, and we show that the current census has hydrogen-burning stars outnumbering brown dwarfs by roughly a factor of six. This factor will decrease with time as more brown dwarfs are identified within this volume, but unless there is a vast reservoir of cold brown dwarfs invisible to WISE, the final space density of brown dwarfs is still expected to fall well below that of stars. We also use these new Y dwarf discoveries, along with newly discovered T dwarfs from WISE, to investigate the field substellar mass function. We find that the overall space density of late-T and early-Y dwarfs matches that from simulations describing the mass function as a power law with slope -0.5 < {alpha} < 0.0; however, a power law may provide a poor fit to the observed object counts as a function of spectral type because there are tantalizing hints that the number of brown dwarfs continues to rise from late-T to early-Y. More detailed monitoring and characterization of these Y dwarfs, along with dedicated searches aimed at identifying more examples, are certainly required.

  15. Mass fractal dimension and spectral dimension to characterize different horizons in La Herreria (Sierra de Guadarrama, Spain)

    Science.gov (United States)

    Inclan, Rosa Maria

    2016-04-01

    Knowledge on three dimensional soil pore architecture is important to improve our understanding of the factors that control a number of critical soil processes as it controls biological, chemical and physical processes at various scales. Computed Tomography (CT) images provide increasingly reliable information about the geometry of pores and solids in soils at very small scale with the benefit that is a non-invasive technique. Fractal formalism has revealed as a useful tool in these cases where highly complex and heterogeneous meda are studied. One of these quantifications is mass dimension (Dm) and spectral dimension (d) applied to describe the water and gas diffusion coefficients in soils (Tarquis et al., 2012). In this work, intact soil samples were collected from the first three horizons of La Herreria soil. This station is located in the lowland mountain area of Sierra de Guadarrama (Santolaria et al., 2015) and it represents a highly degraded type of site as a result of the livestock keeping. The 3D images, of 45.1 micro-m resolution (256x256x256 voxels), were obtained and then binarized following the singularity-CA method (Martín-Sotoca et al. 2016). Based on these images Dm and d were estimated. The results showed an statistical difference in porosity, Dm and d for each horizon. This fact has a direct implication in diffusion parameters for a pore network modeling based on both fractal dimensions. These soil parameters will constitute a basis for site characterization for further studies regarding soil degradation; determining the interaction between soil, plant and atmosphere with respect to human induced activities as well as the basis for several nitrogen and carbon cycles modeling. References Martin Sotoca; J.J. Ana M. Tarquis, Antonio Saa Requejo, and Juan B. Grau (2016). Pore detection in Computed Tomography (CT) soil 3D images using singularity map analysis. Geophysical Research Abstracts, 18, EGU2016-829. Santolaria-Canales, Edmundo and the Gu

  16. Mass anomalous dimension of SU(2) with Nf=8 using the spectral density method

    DEFF Research Database (Denmark)

    Suorsa, Joni M.; Leino, Viljami; Rantaharju, Jarno

    2015-01-01

    SU(2) with Nf=8 is believed to have an infrared conformal fixed point. We use the spectral density method to evaluate the coupling constant dependence of the mass anomalous dimension for massless HEX smeared, clover improved Wilson fermions with Schr\\"odinger functional boundary conditions....

  17. Flow injection mass spectral fingerprints demonstrate chemical differences in rio red grapefruit with respect to year, harvest time, and conventional versus organic farming

    Science.gov (United States)

    Spectral fingerprints were acquired for Ruby Red grapefruit using direct injection-electrospray ionization with time-of-flight and ion trap mass spectrometry (DI-ESI-TOF-MS and DI-ESI-IT-MS). Rio Red grapefruits were harvested 3 times a year (early, mid, and late harvests) in 2005 and 2006 from con...

  18. Core and Wing Densities of Asymmetric Coronal Spectral Profiles: Implications for the Mass Supply of the Solar Corona

    Science.gov (United States)

    Patsourakos, S.; Klimchuk, J. A.; Young, P. R.

    2014-01-01

    Recent solar spectroscopic observations have shown that coronal spectral lines can exhibit asymmetric profiles, with enhanced emissions at their blue wings. These asymmetries correspond to rapidly upflowing plasmas at speeds exceeding approximately equal to 50 km per sec. Here, we perform a study of the density of the rapidly upflowing material and compare it with that of the line core that corresponds to the bulk of the plasma. For this task, we use spectroscopic observations of several active regions taken by the Extreme Ultraviolet Imaging Spectrometer of the Hinode mission. The density sensitive ratio of the Fe(sub XIV) lines at 264.78 and 274.20 Angstroms is used to determine wing and core densities.We compute the ratio of the blue wing density to the core density and find that most values are of order unity. This is consistent with the predictions for coronal nanoflares if most of the observed coronal mass is supplied by chromospheric evaporation driven by the nanoflares. However, much larger blue wing-to-core density ratios are predicted if most of the coronal mass is supplied by heated material ejected with type II spicules. Our measurements do not rule out a spicule origin for the blue wing emission, but they argue against spicules being a primary source of the hot plasma in the corona. We note that only about 40% of the pixels where line blends could be safely ignored have blue wing asymmetries in both Fe(sub XIV) lines. Anticipated sub-arcsecond spatial resolution spectroscopic observations in future missions could shed more light on the origin of blue, red, and mixed asymmetries.

  19. Hysteresis in the spectral states of the neutron star low-mass X-ray binary EXO 1745-248

    CERN Document Server

    Mukherjee, Arunava

    2011-01-01

    We study the low-frequency timing properties and the spectral state evolution of the transient neutron star low-mass X-ray binary EXO 1745-248 using the entire Rossi X-ray Timing Explorer Proportional Counter Array data. We tentatively conclude that EXO 1745-248 is an atoll source, and report the discovery of a ~ 0.45 Hz low-frequency quasi-periodic oscillation and ~ 10 Hz peaked noises. If it is an atoll, this source is unusual because (1) instead of a `C'-like curve, it traced a clear overall clockwise hysteresis curve in each of the colour-colour diagram and the hardness-intensity diagram; and (2) the source took at least 2.5 months to trace the softer banana state, as opposed to a few hours to a day, which is typical for an atoll source. The shape of the hysteresis track was intermediate between the characteristic `q'-like curves of several black hole systems and `C'-like curves of atolls, implying that EXO 1745-248 is an important source for the unification of the black hole and neutron star accretion pr...

  20. High resolution FT-ICR mass spectral analysis of bio-oil and residual water soluble organics produced by hydrothermal liquefaction of the marine microalga Nannochloropsis salina

    Energy Technology Data Exchange (ETDEWEB)

    Sudasinghe, Nilusha; Dungan, Barry; Lammers, Peter; Albrecht, Karl O.; Elliott, Douglas C.; Hallen, Richard T.; Schaub, Tanner

    2014-03-01

    We report a detailed compositional characterization of a bio-crude oil and aqueous by-product from hydrothermal liquefaction of Nannochloropsis salina by direct infusion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) in both positive- and negative-ionization modes. The FT-ICR MS instrumentation approach facilitates direct assignment of elemental composition to >7000 resolved mass spectral peaks and three-dimensional mass spectral images for individual heteroatom classes highlight compositional diversity of the two samples and provide a baseline description of these materials. Aromatic nitrogen compounds and free fatty acids are predominant species observed in both the bio-oil and aqueous fraction. Residual organic compounds present in the aqueous fraction show distributions that are slightly lower in both molecular ring and/or double bond value and carbon number relative to those found in the bio-oil, albeit with a high degree of commonality between the two compositions.

  1. Advances in structure elucidation of small molecules using mass spectrometry

    Science.gov (United States)

    Fiehn, Oliver

    2010-01-01

    The structural elucidation of small molecules using mass spectrometry plays an important role in modern life sciences and bioanalytical approaches. This review covers different soft and hard ionization techniques and figures of merit for modern mass spectrometers, such as mass resolving power, mass accuracy, isotopic abundance accuracy, accurate mass multiple-stage MS(n) capability, as well as hybrid mass spectrometric and orthogonal chromatographic approaches. The latter part discusses mass spectral data handling strategies, which includes background and noise subtraction, adduct formation and detection, charge state determination, accurate mass measurements, elemental composition determinations, and complex data-dependent setups with ion maps and ion trees. The importance of mass spectral library search algorithms for tandem mass spectra and multiple-stage MS(n) mass spectra as well as mass spectral tree libraries that combine multiple-stage mass spectra are outlined. The successive chapter discusses mass spectral fragmentation pathways, biotransformation reactions and drug metabolism studies, the mass spectral simulation and generation of in silico mass spectra, expert systems for mass spectral interpretation, and the use of computational chemistry to explain gas-phase phenomena. A single chapter discusses data handling for hyphenated approaches including mass spectral deconvolution for clean mass spectra, cheminformatics approaches and structure retention relationships, and retention index predictions for gas and liquid chromatography. The last section reviews the current state of electronic data sharing of mass spectra and discusses the importance of software development for the advancement of structure elucidation of small molecules. Electronic supplementary material The online version of this article (doi:10.1007/s12566-010-0015-9) contains supplementary material, which is available to authorized users. PMID:21289855

  2. ION COMPOSITION ELUCIDATION (ICE): A HIGH RESOLUTION MASS SPECTROMETRIC TECHNIQUE FOR IDENTIFYING COMPOUNDS IN COMPLEX MIXTURES

    Science.gov (United States)

    When tentatively identifying compounds in complex mixtures using mass spectral libraries, multiple matches or no plausible matches due to a high level of chemical noise or interferences can occur. Worse yet, most analytes are not in the libraries. In each case, Ion Composition El...

  3. Black Hole Mass Determination In the X-Ray Binary 4U 1630-47: Scaling of Spectral and Variability Characteristics

    Science.gov (United States)

    Seifina, Elena; Titarchuk, Lev; Shaposhnikov, Nikolai

    2014-01-01

    We present the results of a comprehensive investigation on the evolution of spectral and timing properties of the Galactic black hole candidate 4U 1630-47 during its spectral transitions. In particular, we show how a scaling of the correlation of the photon index of the Comptonized spectral component gamma with low-frequency quasi-periodic oscillations (QPOs), ?(sub L), and mass accretion rate, M, can be applied to the black hole mass and the inclination angle estimates.We analyze the transition episodes observed with the Rossi X-Ray Timing Explorer and BeppoSAX satellites.We find that the broadband X-ray energy spectra of 4U 1630-47 during all spectral states can be modeled by a combination of a thermal component, a Comptonized component, and a red-skewed iron-line component. We also establish that gamma monotonically increases during transition from the low-hard state to the high-soft state and then saturates for high mass accretion rates. The index saturation levels vary for different transition episodes. Correlations of gamma versus ?(sub L) also show saturation at gamma (is) approximately 3. Gamma -M and gamma -?(sub L) correlations with their index saturation revealed in 4U 1630-47 are similar to those established in a number of other black hole candidates and can be considered as an observational evidence for the presence of a black hole in these sources. The scaling technique, which relies on XTE J1550-564, GRO 1655-40, and H1743-322 as reference sources, allows us to evaluate a black hole mass in 4U 1630-47 yielding M(sub BH) (is) approximately 10 +/- 0.1 solar masses and to constrain the inclination angle of i (is) approximately less than 70 deg.

  4. Black hole mass determination in the X-ray binary 4U 1630-47: Scaling of spectral and variability characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Seifina, Elena [Moscow M. V. Lomonosov State University/Sternberg Astronomical Institute, Universitetsky Prospect 13, Moscow 119992 (Russian Federation); Titarchuk, Lev [Dipartimento di Fisica, Università di Ferrara, Via Saragat 1, I-44122 Ferrara (Italy); Shaposhnikov, Nikolai, E-mail: seif@sai.msu.ru, E-mail: titarchuk@fe.infn.it, E-mail: lev@milkyway.gsfc.nasa.gov, E-mail: nikolai.v.shaposhnikov@nasa.gov [Goddard Space Flight Center, NASA, Code 663, Greenbelt, MD 20771 (United States)

    2014-07-01

    We present the results of a comprehensive investigation on the evolution of spectral and timing properties of the Galactic black hole candidate 4U 1630-47 during its spectral transitions. In particular, we show how a scaling of the correlation of the photon index of the Comptonized spectral component Γ with low-frequency quasi-periodic oscillations (QPOs), ν {sub L}, and mass accretion rate, M-dot , can be applied to the black hole mass and the inclination angle estimates. We analyze the transition episodes observed with the Rossi X-Ray Timing Explorer and BeppoSAX satellites. We find that the broadband X-ray energy spectra of 4U 1630-47 during all spectral states can be modeled by a combination of a thermal component, a Comptonized component, and a red-skewed iron-line component. We also establish that Γ monotonically increases during transition from the low-hard state to the high-soft state and then saturates for high mass accretion rates. The index saturation levels vary for different transition episodes. Correlations of Γ versus ν {sub L} also show saturation at Γ ∼ 3. Γ-- M-dot and Γ-ν {sub L} correlations with their index saturation revealed in 4U 1630-47 are similar to those established in a number of other black hole candidates and can be considered as an observational evidence for the presence of a black hole in these sources. The scaling technique, which relies on XTE J1550-564, GRO 1655-40, and H1743-322 as reference sources, allows us to evaluate a black hole mass in 4U 1630-47 yielding M {sub BH} ∼ 10 ± 0.1 solar masses and to constrain the inclination angle of i ≲ 70°.

  5. X-ray properties of K-selected galaxies at 0.5mass, redshift and spectral type

    CERN Document Server

    Jones, Therese M; van Dokkum, Pieter G; Brammer, Gabriel; Franx, Marijn; Greene, Jenny E; Labbé, Ivo; Whitaker, Katherine E

    2013-01-01

    We examine how the total X-ray luminosity correlates with stellar mass, stellar population, and redshift for a K-band limited sample of ~3500 galaxies at 0.5spectral energy distributions. For each galaxy type, we further divide the sample into bins of redshift and stellar mass, and perform an X-ray stacking analysis using the Chandra COSMOS (C-COSMOS) data. We find that full band X-ray luminosity is primarily increasing with stellar mass, and at similar mass and spectral type is higher at larger redshifts. When comparing at the same stellar mass, we find that the X-ray luminosity is slightly higher for younger galaxies (i.e., weaker 4000\\AA breaks), but the scatter in this relation is large. We compare the observed X-ray luminosities to those expected from low and high mass X-ray binaries (XRBs). For blue galaxies, XRBs can almost fully account fo...

  6. BEPPOSAX and RXTE spectral study of the low-mass X-ray binary 4u~1705-44. Spectral hardening during the banana branch

    CERN Document Server

    Seifina, Elena; Shrader, Chris; Shaposhnikov, Nikolai

    2015-01-01

    We analyze the X-ray spectra of the atoll 4U~1705-44 when the source undergoes the island-banana state transition. We use the Rossi X-ray Timing Explorer (RXTE) and BeppoSAX observations for this analysis. We demonstrate that the broad-band energy spectral distributions for all evolutinary states can be fitted by a model, consisting two Comptonized components. One arises from the seed photons coming from a neutron star (NS) atmosphere at a temperature kT_{s1}80 keV. This phase is similar to that was previously found in the Z-source Sco X-1. We interpret the decreasing index phase using a model in which a super-Eddington radiation pressure from the neutron star causes an expansion of the Compton cloud similar to that found previously in Sco~X-1 during the Flaring branch.

  7. Comparison between Spectral perturbation and Spectral relaxation approach for unsteady heat and mass transfer by MHD mixed convection flow over an impulsively stretched vertical surface with chemical reaction effect

    Directory of Open Access Journals (Sweden)

    T. M. Agbaje

    2015-06-01

    Full Text Available In this study, the spectral perturbation method (SPM is utilized to solve the momentum, heat and mass transfer equations describing the unsteady MHD mixed convection flow over an impulsively stretched vertical surface in the presence of chemical reaction effect. The governing partial differential equations are reduced into a set of coupled non similar equations and then solved numerically using the SPM. The SPM combines the standard perturbation method idea with the Chebyshev pseudo-spectral collocation method. In order to demonstrate the accuracy and efficiency of the proposed method, the spectral perturbation (SPM numerical results are compared with numerical results generated using the spectral relaxation method (SRM and a good agreement between the two methods is observed up to a minimum of eight decimal digits. Several simulation are conducted to ascertain the accuracy of the SPM and the SRM. The computational speed of the SPM is demonstrated by comparing the SPM computational time with the SRM computational time. A residual error analysis is also conducted for the SPM and the SRM in order to further assess the accuracy of the SPM. The study shows that the spectral perturbation method (SPM is more efficient in terms of computational speed when compared with the SRM. The study also shows that the SPM can be used as an efficient and reliable tool for solving strongly nonlinear boundary value partial differential equation problems that are defined under the Williams and Rhyne [3] transformation. In addition, the study shows that accurate results can be obtained using the perturbation method and thus, the conclusions earlier drawn by researchers regarding the accuracy of perturbation methods is corrected.

  8. Measurement of the strangeness spectral function and the mass of the strange quark in hadronic {tau} decays with the OPAL detector

    Energy Technology Data Exchange (ETDEWEB)

    Mader, W.

    2004-03-01

    Tau lepton decays with open strangeness in the final state are measured with the Opal detector at LEP to determine the strange hadronic spectral function of the {tau} lepton and the mass of the strange quark. The decays {tau}{sup -} {yields} (K{pi}){sup -}{nu}{sub {tau}}, (K{pi}{pi}){sup -}{nu}{sub {tau}} and (K{pi}{pi}{pi}){sup -}{nu}{sub {tau}} with final states consisting of neutral and charged kaons and pions, have been studied. The invariant mass distribution of 93.4% of these final states have been experimentally determined. Monte Carlo simulations have been used for the remaining 6.6% and for the strange final states including {eta} mesons. The reconstructed strange final states, corrected for resolution effects and detection efficiencies, yield the strange spectral function of the {tau} lepton. The moments of the spectral function and the ratio of strange to non-strange moments, which are important input parameters for theoretical analyses, are determined. Furthermore, the branching fractions B({tau}{sup -} {yields} K{sup -}{pi}{sup 0}{nu}{sub {tau}}) = (0.471 {+-} 0.064{sub stat} {+-} 0.021{sub sys})%, B({tau}{sup -} {yields} K{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}}) = (0.415 {+-} 0.059{sub stat} {+-} 0.031{sub sys})% have been measured. From the CKM weighted difference of strange and non-strange spectral moments, the mass of the strange quark at the {tau} mass scale has been determined: m{sub s}(m{sub {tau}}{sup 2}) = (84 {+-} 14{sub exp} {+-} 6{sub V{sub us}} {+-} 17{sub theo}) MeV. Evolving this result to customary scales yields m{sub s}(1 GeV{sup 2}) = (111{sub -35}{sup +26}) MeV, m{sub s}(4 GeV{sup 2}) = (82{sub -25}{sup +19}) MeV. (orig.)

  9. Exploration of polar lipid accumulation profiles in Euglena gracilis using LipidBlast, an MS/MS spectral library constructed in silico.

    Science.gov (United States)

    Ogawa, Takumi; Furuhashi, Takeshi; Okazawa, Atsushi; Nakai, Rai; Nakazawa, Masami; Kind, Tobias; Fiehn, Oliver; Kanaya, Shigehiko; Arita, Masanori; Ohta, Daisaku

    2014-01-01

    A rapid protocol for polar lipid profiling was applied to Euglena gracilis lipid metabolism by LipidBlast, an MS/MS spectral similarity search tool. The similarity search results suggested anoxia-induced polar lipid metabolism in Euglena characterized by the accumulation of differential lipid classes, carbon chain lengths, and unsaturated bond numbers. The informatics-supported MS spectral search provides an alternative option for global lipid profiling studies.

  10. Non-spectral interferences due to the presence of sulfuric acid in inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    García-Poyo, M. Carmen; Grindlay, Guillermo; Gras, Luis [Department of Analytical Chemistry, Nutrition and Food Sciences, University of Alicante, P.O. Box 99, 03080 – Alicante (Spain); Loos-Vollebregt, Margaretha T.C. de, E-mail: margaretha.deloos@ugent.be [Delft University of Technology, Faculty of Applied Sciences, Analytical Biotechnology, Julianalaan 67, 2628 BC Delft (Netherlands); Ghent University, Department of Analytical Chemistry, Krijgslaan 281 - S12, 9000 Ghent (Belgium); Mora, Juan, E-mail: juan.mora@ua.es [Department of Analytical Chemistry, Nutrition and Food Sciences, University of Alicante, P.O. Box 99, 03080 – Alicante (Spain)

    2015-03-01

    Results of a systematic study concerning non-spectral interferences from sulfuric acid containing matrices on a large number of elements in inductively coupled plasma–mass spectrometry (ICP-MS) are presented in this work. The signals obtained with sulfuric acid solutions of different concentrations (up to 5% w w{sup −1}) have been compared with the corresponding signals for a 1% w w{sup −1−} nitric acid solution at different experimental conditions (i.e., sample uptake rates, nebulizer gas flows and r.f. powers). The signals observed for {sup 128}Te{sup +}, {sup 78}Se{sup +} and {sup 75}As{sup +} were significantly higher when using sulfuric acid matrices (up to 2.2-fold for {sup 128}Te{sup +} and {sup 78}Se{sup +} and 1.8-fold for {sup 75}As{sup +} in the presence of 5 w w{sup -1} sulfuric acid) for the whole range of experimental conditions tested. This is in agreement with previously reported observations. The signal for {sup 31}P{sup +} is also higher (1.1-fold) in the presence of sulfuric acid. The signal enhancements for {sup 128}Te{sup +}, {sup 78}Se{sup +}, {sup 75}As{sup +} and {sup 31}P{sup +} are explained in relation to an increase in the analyte ion population as a result of charge transfer reactions involving S{sup +} species in the plasma. Theoretical data suggest that Os, Sb, Pt, Ir, Zn and Hg could also be involved in sulfur-based charge transfer reactions, but no experimental evidence has been found. The presence of sulfuric acid gives rise to lower ion signals (about 10–20% lower) for the other nuclides tested, thus indicating the negative matrix effect caused by changes in the amount of analyte loading of the plasma. The elemental composition of a certified low-density polyethylene sample (ERM-EC681K) was determined by ICP-MS after two different sample digestion procedures, one of them including sulfuric acid. Element concentrations were in agreement with the certified values, irrespective of the acids used for the digestion. These

  11. Rapid analysis of phthalic acid esters in environmental water using fast elution gas chromatography with mass spectrometry and adaptive library spectra.

    Science.gov (United States)

    Li, Pao; Mei, Zhen; Cai, Wensheng; Shao, Xueguang

    2014-07-01

    A method for the fast determination of the components in a complex sample by using gas chromatography with mass spectrometry was developed and used for the quantitative analysis of phthalic acid esters in environmental water. In the method, the adaptively corrected mass spectra were used to compensate for the differences between the library spectra and the measured ones in the experiment. The correction was obtained by the iterative transformation of the library spectra using iterative target transformation factor analysis, and the resolution was performed by non-negative immune algorithm using the corrected spectra. Rapid analysis of 16 phthalic acid esters in water samples was achieved using fast elution gas chromatography with mass spectrometry measurements. The results show that the mass spectra and chromatographic profiles of the phthalic acid esters can be obtained from the overlapping signal of 13 min elution, and accurate quantitative analysis can be obtained. The recoveries of the phthalic acid esters obtained by standard addition are between 90.3 and 107.4%, and the relative standard deviations obtained in repeated measurements are less than 9%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. The value of energy spectral CT in the differential diagnosis between benign and malignant soft tissue masses of the musculoskeletal system

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xin [Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong (China); Shao, Xiaodong [Department of Radiology, Qingdao Municipal Hospital, Qingdao, Shandong (China); Chen, Haisong, E-mail: chsEJR@163.com [Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong (China)

    2015-06-15

    Highlights: • Different types of tissues have different types of spectral curves. • We find that spectral curve is useful in the differential diagnosis of benign and malignant tumor of the musculoskeletal system. • Arc shaped curve is a specific sign for tumors containing abundant fat. - Abstract: Objective: To explore the value of energy spectral CT in the differential diagnosis between benign and malignant tumor of the musculoskeletal system. Methods: Energy spectral CT scan was performed on 100 patients with soft tissue mass caused by musculoskeletal tumors found by MRI. Solid areas with homogenous density were chosen as region of interests (ROI), avoiding necrosis, hemorrhage and calcification region. Select the optimal keV on single energy images, and then the keV–CT curve was automatically generated. All 100 cases of tumors proved by histological examination were divided into four groups, 38 cases were in benign group, 10 cases in borderline group, 49 cases in malignant group, and 3 cases of lipoma (that were analyzed separately since its curve was arc shaped, significantly different from other curves). The formula used to calculate the slope of spectral curve was as follows: slope = (Hu40 keV − Hu80 keV)/40. As the slope was steep within the range of 40–80 keV based on preliminary observations, 40 keV and 80 keV were used as the reference points to calculate the slope value of the energy spectral curve. Kruskal–Wallis rank sum test was applied for statistical analysis, and P < 0.05 was considered to indicate a statistically significant difference. Results: The spectral curve of benign group was gradually falling type with a mean slope of 0.75 ± 0.30, that of malignant group was sharply falling type with a mean slope of 1.64 ± 1.00, and that of borderline group was a falling type between the above two groups with a mean slope of 1.34 ± 0.45. The differences of slopes between benign and malignant group, benign and borderline group were of

  13. ESO 243-49 HLX-1: scaling of X-ray spectral properties and black hole mass determination

    OpenAIRE

    Titarchuk, Lev; Seifina, Elena

    2016-01-01

    We report the results of Swift/XRT observations (2008-2015) of a hyper-luminous X-ray source, ESO 243-49 HLX-1. We found a strong observational evidence that ESO 243-49 HLX-1 underwent spectral transitions from the low/hard state to the high/soft state during these observations. The spectra of ESO 243-49 HLX-1 are well fitted by the so-{called} bulk motion Comptonization model for all spectral states. We have established the photon index Gamma saturation level, Gamma_{sat}$=3.0+/-0.1, in the ...

  14. Measurement of the Strangeness Spectral Function and the Mass of the Strange Quark in Hadronic tau Decays with the OPAL Detector

    CERN Document Server

    Mader, Wolfgang Franz

    2004-01-01

    Tau lepton decays with open strangeness in the final state are measured with the Opal detector at LEP to determine the strange hadronic spectral function of the τ lepton and the mass of the strange quark. The decays τ −→ (Kπ) −ντ , (Kππ) −ντ and (Kπππ) −ντ with final states consisting of neutral and charged kaons and pions, have been studied. The invariant mass distribution of 93.4% of these final states have been experimentally determined. Monte Carlo simulations have been used for the remaining 6.6% and for the strange final states including η mesons. The reconstructed strange final states, corrected for resolution effects and detection efficiencies, yield the strange spectral function of the τ lepton. The moments of the spectral function and the ratio of strange to non-strange moments, which are important input parameters for theoretical analyses, are determined. Furthermore, the branching fractions B(τ − → K −π 0 ντ ) = (0.471 ± 0.064stat ± 0.021sys) % B(τ − → K ...

  15. High Resolution Imaging of Very Low Mass Spectral Binaries: Three Resolved Systems and Detection of Orbital Motion in an L/T Transition Binary

    CERN Document Server

    Gagliuffi, Daniella C Bardalez; Burgasser, Adam J

    2015-01-01

    We present high resolution Laser Guide Star Adaptive Optics imaging of 43 late-M, L and T dwarf systems with Keck/NIRC2. These include 17 spectral binary candidates, systems whose spectra suggest the presence of a T dwarf secondary. We resolve three systems: 2MASS J1341$-$3052, SDSS J1511+0607 and SDSS J2052$-$1609; the first two are resolved for the first time. All three have projected separations $<8$ AU and estimated periods of $14-80$ years. We also report a preliminary orbit determination for SDSS J2052$-$1609 based on six epochs of resolved astrometry between 2005$-$2010. Among the 14 unresolved spectral binaries, 5 systems were confirmed binaries but remained unresolved, implying a minimum binary fraction of $47^{+12}_{-11}\\%$ for this sample. Our inability to resolve most of the spectral binaries, including the confirmed binaries, supports the hypothesis that a large fraction of very low mass systems have relatively small separations and are missed with direct imaging.

  16. jmzReader: A Java parser library to process and visualize multiple text and XML-based mass spectrometry data formats.

    Science.gov (United States)

    Griss, Johannes; Reisinger, Florian; Hermjakob, Henning; Vizcaíno, Juan Antonio

    2012-03-01

    We here present the jmzReader library: a collection of Java application programming interfaces (APIs) to parse the most commonly used peak list and XML-based mass spectrometry (MS) data formats: DTA, MS2, MGF, PKL, mzXML, mzData, and mzML (based on the already existing API jmzML). The library is optimized to be used in conjunction with mzIdentML, the recently released standard data format for reporting protein and peptide identifications, developed by the HUPO proteomics standards initiative (PSI). mzIdentML files do not contain spectra data but contain references to different kinds of external MS data files. As a key functionality, all parsers implement a common interface that supports the various methods used by mzIdentML to reference external spectra. Thus, when developing software for mzIdentML, programmers no longer have to support multiple MS data file formats but only this one interface. The library (which includes a viewer) is open source and, together with detailed documentation, can be downloaded from http://code.google.com/p/jmzreader/. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Identification of polybrominated diphenyl ether metabolites based on calculated boiling points from COSMO-RS, experimental retention times, and mass spectral fragmentation patterns.

    Science.gov (United States)

    Simpson, Scott; Gross, Michael S; Olson, James R; Zurek, Eva; Aga, Diana S

    2015-02-17

    The COnductor-like Screening MOdel for Realistic Solvents (COSMO-RS) was used to predict the boiling points of several polybrominated diphenyl ethers (PBDEs) and methylated derivatives (MeO-BDEs) of monohydroxylated BDE (OH-BDE) metabolites. The linear correlation obtained by plotting theoretical boiling points calculated by COSMO-RS against experimentally determined retention times from gas chromatography-mass spectrometry facilitated the identification of PBDEs and OH-BDEs. This paper demonstrates the applicability of COSMO-RS in identifying unknown PBDE metabolites of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and 2,2',4,4',6-pentabromodiphenyl ether (BDE-100). Metabolites of BDE-47 and BDE-100 were formed through individual incubations of each PBDE with recombinant cytochrome P450 2B6. Using calculated boiling points and characteristic mass spectral fragmentation patterns of the MeO-BDE positional isomers, the identities of the unknown monohydroxylated metabolites were proposed to be 2'-hydroxy-2,3',4,4'-tetrabromodiphenyl ether (2'-OH-BDE-66) from BDE-47, and 2'-hydroxy-2,3',4,4',6-pentabromodiphenyl ether (2'-OH-BDE-119) and 4-hydroxy-2,2',3,4',6-pentabromodiphenyl ether (4-OH-BDE-91) from BDE-100. The collective use of boiling points predicted with COSMO-RS, and characteristic mass spectral fragmentation patterns provided a valuable tool toward the identification of isobaric compounds.

  18. The AKARI 2.5-5.0 Micron Spectral Atlas of Type-1 Active Galactic Nuclei: Black Hole Mass Estimator, Line Ratio, and Hot Dust Temperature

    CERN Document Server

    Kim, Dohyeong; Kim, Ji Hoon; Jun, Hyunsung David; Woo, Jong-Hak; Lee, Hyung Mok; Lee, Myung Gyoon; Nakagawa, Takao; Matsuhara, Hideo; Wada, Takehiko; Oyabu, Shinki; Takagi, Toshinobu; Ohyama, Youichi; Lee, Seong-Kook

    2015-01-01

    We present 2.5-5.0 $\\mu$m spectra of 83 nearby ($0.002\\,<\\,z\\,<\\,0.48$) and bright ($K<14$mag) type-1 active galactic nuclei (AGNs) taken with the Infrared Camera (IRC) on board $\\it{AKARI}$. The 2.5-5.0 $\\mu$m spectral region contains emission lines such as Br$\\beta$ (2.63 $\\mu$m), Br$\\alpha$ (4.05 $\\mu$m), and polycyclic aromatic hydrocarbons (PAH; 3.3 $\\mu$m), which can be used for studying the black hole (BH) masses and star formation activities in the host galaxies of AGNs. The spectral region also suffers less dust extinction than in the ultra violet (UV) or optical wavelengths, which may provide an unobscured view of dusty AGNs. Our sample is selected from bright quasar surveys of Palomar-Green (PG) and SNUQSO, and AGNs with reverberation-mapped BH masses from Peterson et al. (2004). Using 11 AGNs with reliable detection of Brackett lines, we derive the Brackett-line-based BH mass estimators. We also find that the observed Brackett line ratios can be explained with the commonly adopted physica...

  19. Systematic Charge-to-Mass-Dependence of Heavy Ion Spectral Breaks in Large Gradual Solar Energetic Particle Events

    Science.gov (United States)

    Desai, Mihir; Mason, Glenn; McComas, David; Cohen, Christina; Smith, Charles; Ebert, Robert; Schwadron, Nathan; Li, Gang; Mewaldt, Richard; Dayeh, Maher A.

    2016-07-01

    We fit the ˜0.1-500 MeV/nucleon H-Fe spectra in 46 large SEP events surveyed by Desai et al. (2015) with the double power-law Band function to obtain a normalization constant, low- and high-energy Band parameters γ_a and γ_b; and spectral break energy E_B. We also calculate the low-energy power-law spectral slope γ_1. Our results are: 1) γ_a, γ_1, and γ_b are species-independent and the spectra steepen with increasing energy; 2) the low-energy power-law spectral slopes γ_1 are consistent with diffusive acceleration at shocks with compression ratios between ˜2-4 as predicted by Schwadron et al. (2015); 3) the spectral breaks E_B's are well ordered by Q/M ratio, and decrease systematically with decreasing Q/M, scaling as (Q/M)^α with α in most events varying between ˜0.2-2, as predicted by Li et al (2009); 4) α is well correlated with Fe/O at ˜0.16-0.23 MeV/nucleon, but not with the ˜15-21 MeV/nucleon Fe/O and the ˜0.5-2.0 MeV/nucleon ^3He/^4He ratios; 5) In most events: α3, and O E_B increases with γ_b - γ_a; and 6) Many extreme events (associated with faster CMEs and GLEs) are Fe-rich and ^3He-rich, have α≳1.4, flatter spectra at low and high energies with γ_b - γ_a high and low energy occur because enhanced wave power enables faster CME shocks to accelerate flare suprathermals more efficiently than ambient coronal ions.

  20. Estimation of Mass of Compact Object in H 1743-322 from 2010 and 2011 Outbursts using TCAF Solution and Spectral Index–QPO Frequency Correlation

    Science.gov (United States)

    Molla, Aslam Ali; Chakrabarti, Sandip K.; Debnath, Dipak; Mondal, Santanu

    2017-01-01

    The well-known black hole candidate (BHC) H 1743-322 exhibited temporal and spectral variabilities during several outbursts. The variation of the accretion rates and flow geometry that change on a daily basis during each of the outbursts can be very well understood using the recent implementation of the two-component advective flow solution of the viscous transonic flow equations as an additive table model in XSPEC. This has dramatically improved our understanding of accretion flow dynamics. Most interestingly, the solution allows us to treat the mass of the BHC as a free parameter and its mass could be estimated from spectral fits. In this paper, we fitted the data of two successive outbursts of H 1743-322 in 2010 and 2011 and studied the evolution of accretion flow parameters, such as two-component (Keplerian and sub-Keplerian) accretion rates, shock location (i.e., size of the Compton cloud), etc. We assume that the model normalization remains the same across the states in both these outbursts. We used this to estimate the mass of the black hole and found that it comes out in the range of 9.25{--}12.86 {M}ȯ . For the sake of comparison, we also estimated mass using the Photon index versus Quasi Periodic Oscillation frequency correlation method, which turns out to be 11.65+/- 0.67 {M}ȯ using GRO J1655-40 as a reference source. Combining these two estimates, the most probable mass of the compact object becomes {11.21}-1.96+1.65 {M}ȯ .

  1. A mass, energy, enstrophy and vorticity conserving (MEEVC) mimetic spectral element discretization for the 2D incompressible Navier-Stokes equations

    CERN Document Server

    Palha, Artur

    2016-01-01

    In this work we present a mimetic spectral element discretization for the 2D incompressible Navier-Stokes equations that in the limit of vanishing dissipation exactly preserves mass, kinetic energy, enstrophy and total vorticity on unstructured grids. The essential ingredients to achieve this are: (i) a velocity-vorticity formulation in rotational form, (ii) a sequence of function spaces capable of exactly satisfying the divergence free nature of the velocity field, and (iii) a conserving time integrator. Proofs for the exact discrete conservation properties are presented together with numerical test cases on highly irregular grids.

  2. A mass, energy, enstrophy and vorticity conserving (MEEVC) mimetic spectral element discretization for the 2D incompressible Navier-Stokes equations

    Science.gov (United States)

    Palha, A.; Gerritsma, M.

    2017-01-01

    In this work we present a mimetic spectral element discretization for the 2D incompressible Navier-Stokes equations that in the limit of vanishing dissipation exactly preserves mass, kinetic energy, enstrophy and total vorticity on unstructured triangular grids. The essential ingredients to achieve this are: (i) a velocity-vorticity formulation in rotational form, (ii) a sequence of function spaces capable of exactly satisfying the divergence free nature of the velocity field, and (iii) a conserving time integrator. Proofs for the exact discrete conservation properties are presented together with numerical test cases on highly irregular triangular grids.

  3. Reaction profiling by ultra high-pressure liquid chromatography/time-of-flight mass spectrometry in support of the synthesis of DNA-encoded libraries.

    Science.gov (United States)

    Hargiss, Leonard O; Zipp, G Greg; Jessop, Theodore C; Sun, Xuejun; Keyes, Philip; Rawlins, David B; Liang, Zhi; Park, Kum Joo; Gu, Huizhong

    2014-11-15

    An ultra high-pressure liquid chromatography/mass spectrometry (UHPLC/MS) separation and analysis method has been devised for open access analysis of synthetic reactions used in the production of DNA-encoded chemical libraries. The aqueous mobile phase is 100mM hexafluoroisopropanol and 8.6mM triethylamine; the organic mobile phase is methanol. The UHPLC separation uses a C18 OST column (50mm×2.1mm×1.7μm) at 60°C, with a flow rate of 0.6mL/min. Gradient concentration is from 10 to 40% B in 1.0min, increasing to 95% B at 1.2min. Cycle time was about 5min. This method provides a detection limit of a 20-mer oligonucleotide by mass spectrometry of better than 1pmol on-column. Linear UV response for 20-mer extends from 2 to 200pmol/μL in concentration, same-day relative average deviations are less than 5% and bias (observed minus expected) is less than 10%. Deconvoluted mass spectra are generated for components in the predicted mass range using a maximum entropy algorithm. Mass accuracy of deconvoluted spectra is typically 20ppm or better for isotopomers of oligonucleotides up to 7000Da.

  4. Reliable characterization of coffee bean aroma profiles by automated headspace solid phase microextraction-gas chromatography-mass spectrometry with the support of a dual-filter mass spectra library.

    Science.gov (United States)

    Mondello, Luigi; Costa, Rosaria; Tranchida, Peter Quinto; Dugo, Paola; Lo Presti, Maria; Festa, Saverio; Fazio, Alessia; Dugo, Giovanni

    2005-06-01

    This investigation is based on the automated solid phase microextraction GC-MS analysis of the volatile fraction of a variety of coffee bean matrices. Volatile analytes were extracted by headspace (HS)-SPME which was achieved with the support of automated instrumentation. The research was directed towards various important aspects relating to coffee aroma analysis: monitoring of the volatile fraction formation during roasting; chromatographic differentiation of the two main coffee species (Arabica and Robusta) and of a single species from different geographical origins; evaluation of the influence of specific industrial treatments prior to roasting. Reliable peak assignment was carried out through the use of a recently laboratory-constructed "flavour and fragrance" library and a dual-filter MS spectral search procedure. Further emphasis was placed on the automated SPME instrumentation and on its ability to supply highly repeatable chromatographic data.

  5. A Wide-Field Fluorescence Microscope Extension for Ultrafast Screening of One-Bead One-Compound Libraries Using a Spectral Image Subtraction Approach.

    Science.gov (United States)

    Heusermann, Wolf; Ludin, Beat; Pham, Nhan T; Auer, Manfred; Weidemann, Thomas; Hintersteiner, Martin

    2016-05-09

    The increasing involvement of academic institutions and biotech companies in drug discovery calls for cost-effective methods to identify new bioactive molecules. Affinity-based on-bead screening of combinatorial one-bead one-compound libraries combines a split-mix synthesis design with a simple protein binding assay operating directly at the bead matrix. However, one bottleneck for academic scale on-bead screening is the unavailability of a cheap, automated, and robust screening platform that still provides a quantitative signal related to the amount of target protein binding to individual beads for hit bead ranking. Wide-field fluorescence microscopy has long been considered unsuitable due to significant broad spectrum autofluorescence of the library beads in conjunction with low detection sensitivity. Herein, we demonstrate how such a standard microscope equipped with LED-based excitation and a modern CMOS camera can be successfully used for selecting hit beads. We show that the autofluorescence issue can be overcome by an optical image subtraction approach that yields excellent signal-to-noise ratios for the detection of bead-associated target proteins. A polymer capillary attached to a semiautomated bead-picking device allows the operator to efficiently isolate individual hit beads in less than 20 s. The system can be used for ultrafast screening of >200,000 bead-bound compounds in 1.5 h, thereby making high-throughput screening accessible to a wider group within the scientific community.

  6. Mass Spectral Studies of 1-(2-Chloroethoxy)-2-[(2-chloroethyl)thio] Ethane and Related Compounds Using Gas ChromatographyMass Spectrometry and Gas ChromatographyTriple-Quadrupole Mass Spectrometry

    Science.gov (United States)

    2016-02-01

    spectral studies were performed to facilitate the development of a spectral database of mustard- related compounds for verification purposes in support of...development of a spectral database of mustard compounds for verification and identification purposes in support of the Chemical Weapons Convention...Andersson, G. Analysis of Two Chemical Weapons Samples from the Iran–Iraq War; NBC Defence and Technology International : New York, 1986; pp 62–65. 2

  7. Estimation of Mass of Compact Object in H 1743-322 from 2010 and 2011 Outbursts using TCAF Solution and Spectral Index - QPO Frequency Correlation

    CERN Document Server

    Molla, Aslam Ali; Debnath, Dipak; Mondal, Santanu

    2016-01-01

    The well known black hole candidate H~1743-322 exhibited temporal and spectral variabilities during several outbursts. Daily variation of the accretion rates and the flow geometry change on a daily basis during each of the outbursts could be understood very well using the recent implementation of two component advective flow (TCAF) solution of the viscous transonic flow equations as an additive table model in XSPEC. This has dramatically improved our understanding about the accretion flow dynamics. Most interestingly, the solution allows to treat mass of the black hole candidate as a free parameter and there mass could be estimated from spectral fits. In this paper, we fit the data of two successive outbursts of H~1743-322 in 2010 and 2011 and studied evolutions of accretion flow parameters, such as, two component (Keplerian and sub-Keplerian) accretion rates, shock location (i.e., size of the Compton cloud), etc. We assume that the model Normalization remains the same accross the states in both these outburs...

  8. Desorption/Ionization Fluence Thresholds and Improved Mass Spectral Consistency Measured Using a Flattop Laser Profile in the Bioaerosol Mass Spectrometry of Single Bacillus Endospores

    Energy Technology Data Exchange (ETDEWEB)

    Steele, P T; Srivastava, A; Pitesky, M E; Fergenson, D P; Tobias, H J; Gard, E E; Frank, M

    2004-11-30

    Bioaerosol mass spectrometry (BAMS) is being developed to analyze and identify biological aerosols in real-time. Mass spectra of individual Bacillus endospores were measured here with a bipolar aerosol time-of-flight mass spectrometer in which molecular desorption and ionization were produced using a single laser pulse from a Q-switched, frequency-quadrupled Nd:YAG laser that was modified to have an approximately flattop profile. The flattened laser profile allowed the minimum fluence required to desorb and ionize significant numbers of ions from single aerosol particles to be determined. For Bacillus spores this threshold had a mean value of approximately 1 nJ/{micro}m{sup 2} (0.1 J/cm{sup 2}). Thresholds for individual spores, however, could apparently deviate by 20% or more from the mean. Threshold distributions for clumps of MS2 bacteriophage and bovine serum albumin were subsequently determined. Finally, the flattened profile was observed to increase the reproducibility of single spore mass spectra. This is consistent with the general conclusions of our earlier paper on the fluence dependence of single spore mass spectra and is particularly significant because it is expected to enable more robust differentiation and identification of single bioaerosol particles.

  9. Posicionamiento de las bibliotecas universitarias peruanas en los medios de comunicación Positioning of peruvian university libraries in mass media

    Directory of Open Access Journals (Sweden)

    Alonso Estrada-Cuzcano

    2010-08-01

    Full Text Available El propósito de este trabajo es analizar la presencia de las bibliotecas universitarias peruanas en los medios de comunicación del país. Para tal fin se investigaron 37 medios [escritos] (diarios, revistas, agencias de noticias y radios de cobertura regional y nacional, y se tomaron en consideración las notas o noticias, columnas, artículos, entrevistas y publicidad que hicieran referencia a este tipo de bibliotecas. La investigación ha demostrado que la presencia de las bibliotecas universitarias en los medios de comunicación es marginal, puesto que en tres años, comprendidos entre enero de 2007 y diciembre de 2009, sólo se pudieron encontrar 43 ocurrencias, a pesar de que muchas bibliotecas (o universidades tienen oficinas de imagen institucional. Estas ocurrencias están distribuidas entre 17 universidades de un total de 98 existentes en el país lo cual demuestra que aún no hay una corriente que fomente el posicionamiento de estas bibliotecas.The purpose of this work is to assess the profile of Peruvian university libraries in mass media. To this end, thirty-seven media outlets, including daily newspapers, magazines, wire services and radio stations providing regional and national coverage were monitored and/or examined. Over a period of three years, straight news stories, columns, feature articles, interviews and advertising referring to university-based libraries were tabulated, showing for the universe of 98 universities in the country a mere 43 mentions, despite the fact that many universities have institutional communications and media offices. These results suggest that currently little effort is being made to enhance or develop the positioning of university libraries.

  10. Simulation of heat and mass transfer in turbulent channel flow using the spectral-element method: effect of spatial resolution

    Science.gov (United States)

    Ryzhenkov, V.; Ivashchenko, V.; Vinuesa, R.; Mullyadzhanov, R.

    2016-10-01

    We use the open-source code nek5000 to assess the accuracy of high-order spectral element large-eddy simulations (LES) of a turbulent channel flow depending on the spatial resolution compared to the direct numerical simulation (DNS). The Reynolds number Re = 6800 is considered based on the bulk velocity and half-width of the channel. The filtered governing equations are closed with the dynamic Smagorinsky model for subgrid stresses and heat flux. The results show very good agreement between LES and DNS for time-averaged velocity and temperature profiles and their fluctuations. Even the coarse LES grid which contains around 30 times less points than the DNS one provided predictions of the friction velocity within 2.0% accuracy interval.

  11. Retrieval of aerosol mass load (PM10 from MERIS/Envisat top of atmosphere spectral reflectance measurements over Germany

    Directory of Open Access Journals (Sweden)

    M. Vountas

    2011-03-01

    Full Text Available Results of a new methodology for retrievals of surface particulate matter concentration (PM10 from satellite reflectance measurements over Germany are presented in this paper. The retrieval derives effective radii from Ångström-α exponents and benefits from the fitting of a smooth spectral slope from seven MERIS spectrometer channels. Comparisons with ground measurements from the air quality surveillance show standard deviations of 33.9% with −18.9% bias over Hamburg. Over rural sites a standard deviation of 17.9% (bias 12.9% is reached. We discuss critically limitations and potential applications of the retrieval. Additionally, we talk about the aspects at comparing of retrieved particulate matter with ground station measurements.

  12. Application of high-throughput affinity-selection mass spectrometry for screening of chemical compound libraries in lead discovery.

    Science.gov (United States)

    Zehender, Hartmut; Mayr, Lorenz M

    2007-02-01

    High-throughput screening of chemical libraries for compounds that interfere with a particular molecular target is among the most powerful methodologies applied in lead discovery at present. In this review, the authors describe a label-free, homogeneous, affinity-selection-based technology developed at Novartis, termed SpeedScreen, which is compared with similar technologies used for high-throughput screening in the pharmaceutical and biotechnology industries. The focus at present of SpeedScreen is twofold: first, this technology is applied to orphan genomic targets and to those targets that are non-tractable by a functional assay; second, this technology is applied complementary to the well-established traditional methodologies for the screening of molecular targets. In summary, the authors discuss the value of affinity-selection-based high-throughput screening as a complementary technology to the common functional screening platforms and the benefits as well as the limitations of this new technology are outlined.

  13. Broad Screening and Identification of Novel Psychoactive Substances in Plasma by High-Performance Liquid Chromatography-High-Resolution Mass Spectrometry and Post-run Library Matching.

    Science.gov (United States)

    Montesano, Camilla; Vannutelli, Gabriele; Gregori, Adolfo; Ripani, Luigi; Compagnone, Dario; Curini, Roberta; Sergi, Manuel

    2016-09-01

    Drug abuse is today a growing global problem. Often the consumers are not aware about the type of substances they are using and the correlated risks. In recent years, new psychoactive substances (NPS) appeared in the illicit market. The presence of NPS, such as synthetic cathinones, cannabinoids and phenethylamines, which are known to be pharmacologically and toxicologically hazardous, has been frequently reported. The aim of this study was the development of a liquid chromatography-high-resolution mass spectrometry (LC-HRMS) method for a broad screening of NPS in plasma. Data acquisition was in MS/MS and full-scan modes and the method was validated for 25 NPS belonging to different chemical classes. Quantitative results have been obtained for these analytes with limits of quantification ranging from 0.03 to 0.4 ng/mL. The method was proven to be suitable for the screening of additional substances; to this aim, a post-run library matching was conducted for every sample with an in-house database containing over 300 NPS and known metabolites. The library may be constantly expanded with new drugs, in order to obtain a broad screening of NPS in biological matrices.

  14. Lipopeptides from the Banyan Endophyte, Bacillus subtilis K1: Mass Spectrometric Characterization of a Library of Fengycins

    Science.gov (United States)

    Pathak, Khyati V.; Keharia, Haresh; Gupta, Kallol; Thakur, Suman S.; Balaram, Padmanabhan

    2012-10-01

    Mass spectrometric analysis of a banyan endophyte, Bacillus subtilis K1, extract showing broad spectrum antifungal activity revealed a complex mixture of lipopeptides, iturins, surfactins, and fengycins. Fractionation by reversed-phase high performance liquid chromatography (HPLC) facilitated a detailed analysis of fengycin microheterogeneity. Matrix assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass spectrometric studies permitted the identification of several new fengycin variants. Four major sites of heterogeneity are identified: (1) N-terminus β-hydroxy fatty acid moiety, where chain length variation and the presence of unsaturation occur, (2) position 6 (Ala/Val/Ile/Leu), (3) position 10 (Val/Ile) within the macrocyclic ring, and (4) Gln to Glu replacement at position 8, resulting in fengycin variants that differ in mass by 1 Da. Diagnostic fragment ions provide a quick method for localizing the sites of variation in the macrocycle or the linear segment. Subsequent establishment of the sequences is achieved by MS/MS analysis of linear fengycin species produced by hydrolysis of the macrocyclic lactone. Unsaturation in the fatty acid chain and the presence of linear precursors in the B. subtilis K1 extract are also established by mass spectrometry. The anomalous distribution of intensities within isotopic multiplets is a diagnostic for Gln/Glu replacements. High resolution mass spectrometry facilitates the identification of fengycin species differing by 1 Da by localizing the variable position (Gln8/Glu8) in the fengycin variants.

  15. Optimal renormalization and the extraction of strange quark mass from moments of $\\tau$-decay spectral function

    CERN Document Server

    Ananthanarayan, B

    2016-01-01

    We introduce an optimal renormalization group analysis pertinent to the analysis of polarization functions associated with the $s$-quark mass relevant in $\\tau$-decay. The technique is based on the renormalization group invariance constraints which lead to closed form summation of all the leading and next-to-leading logarithms at each order in perturbation theory. The new perturbation series exhibit reduced sensitivity to renormalization scale and improved behavior in the complex plane along the integration contour. Using improved experimental and theory inputs we have extracted the value of strange quark mass $m_s(2{\\rm GeV}) = 106.70 \\pm 9.36~{\\rm MeV}$ and $m_s(2{\\rm GeV}) = 74.47 \\pm 7.77~{\\rm MeV}$ from presently available ALEPH and OPAL data respectively. These determinations are in agreement with the determinations in other phenomenological methods and from the lattice.

  16. Synthetic observations of first hydrostatic cores in collapsing low-mass dense cores. I. Spectral energy distributions and evolutionary sequence

    OpenAIRE

    Commercon, Benoit; Launhardt, Ralf; Dullemond, Cornelis P.; Henning, Thomas

    2012-01-01

    The low-mass star formation evolutionary sequence is relatively well-defined both from observations and theoretical considerations. The first hydrostatic core is the first protostellar equilibrium object that is formed during the star formation process. Using state-of-the-art radiation-magneto-hydrodynamic 3D adaptive mesh refinement calculations, we aim to provide predictions for the dust continuum emission from first hydrostatic cores. We investigate the collapse and the fragmentation of ma...

  17. Discriminating between cultivars and treatments of broccoli using mass spectral fingerprinting and analysis of variance-principal component analysis.

    Science.gov (United States)

    Luthria, Devanand L; Lin, Long-Ze; Robbins, Rebecca J; Finley, John W; Banuelos, Gary S; Harnly, James M

    2008-11-12

    Metabolite fingerprints, obtained with direct injection mass spectrometry (MS) with both positive and negative ionization, were used with analysis of variance-principal components analysis (ANOVA-PCA) to discriminate between cultivars and growing treatments of broccoli. The sample set consisted of two cultivars of broccoli, Majestic and Legacy, the first grown with four different levels of Se and the second grown organically and conventionally with two rates of irrigation. Chemical composition differences in the two cultivars and seven treatments produced patterns that were visually and statistically distinguishable using ANOVA-PCA. PCA loadings allowed identification of the molecular and fragment ions that provided the most significant chemical differences. A standardized profiling method for phenolic compounds showed that important discriminating ions were not phenolic compounds. The elution times of the discriminating ions and previous results suggest that they were common sugars and organic acids. ANOVA calculations of the positive and negative ionization MS fingerprints showed that 33% of the variance came from the cultivar, 59% from the growing treatment, and 8% from analytical uncertainty. Although the positive and negative ionization fingerprints differed significantly, there was no difference in the distribution of variance. High variance of individual masses with cultivars or growing treatment was correlated with high PCA loadings. The ANOVA data suggest that only variables with high variance for analytical uncertainty should be deleted. All other variables represent discriminating masses that allow separation of the samples with respect to cultivar and treatment.

  18. Charge-to-mass dependence of heavy ion spectral breaks in large gradual solar energetic particle events

    Science.gov (United States)

    Desai, M. I.; Mason, G. M.; Dayeh, M. A.; Ebert, R. W.; McComas, D. J.; Li, G.; Cohen, C. M. S.; Mewaldt, R. A.; Schwadron, N. A.; Smith, C. W.

    2016-11-01

    We fit the ∼0.1-500 MeV/nucleon H-Fe spectra in 46 large SEP events surveyed by [1] with the double power-law Band function to obtain a normalization constant, low- and high-energy parameters γa and γb ; and break energy EB . We also calculate the low-energy power-law spectral slope γ1. We find that: 1) γa , γ1, and γb are species-independent within a given SEP event, and the spectra steepen with increasing energy; 2) EB ’s are well ordered by Q/M ratio, and decrease systematically with decreasing Q/M, scaling as (Q/M)α with α varying between ∼0.2-3 3) α is well correlated with Fe/O at ∼0.16-0.23 MeV/nucleon and CME speed; 4) In most events: α 3 and 5) Seven out of nine extreme SEP events (associated with faster CMEs and GLEs) are Fe-rich and have α >1.4 with flat spectra at low and high energies yielding γb -γa high- and low-energy and stronger Q/M-dependence of EB (larger α values) occur due to enhanced wave power, which also enables the faster CME shocks to accelerate flare suprathermals more efficiently than ambient coronal ions.

  19. Herschel/PACS far-IR spectral imaging of a jet from an intermediate mass protostar in the OMC-2 region

    CERN Document Server

    Gonzalez-Garcia, B; Watson, D M; Vavrek, R; Megeath, S T; Stutz, A M; Osorio, M; Wyrowski, F; Fischer, W J; Tobin, J J; Sanchez-Portal, M; Rodriguez, A K Diaz; Wilson, T L

    2016-01-01

    We present the first detection of a jet in the far-IR [O I] lines from an intermediate mass protostar. We have carried out a Herschel/PACS spectral mapping study in the [O I] lines of OMC-2 FIR 3 and FIR 4, two of the most luminous protostars in Orion outside of the Orion Nebula. The spatial morphology of the fine structure line emission reveals the presence of an extended photodissociation region (PDR) and a narrow, but intense jet connecting the two protostars. The jet seen in [O I] emission is spatially aligned with the Spitzer/IRAC 4.5 micron jet and the CO (6-5) molecular outflow centered on FIR 3. The mass loss rate derived from the total [O I] 63 micron line luminosity of the jet is 7.7 x 10^-6 M_sun/yr, more than an order of magnitude higher than that measured for typical low mass class 0 protostars. The implied accretion luminosity is significantly higher than the observed bolometric luminosity of FIR 4, indicating that the [O I] jet is unlikely to be associated with FIR 4. We argue that the peak lin...

  20. The effect of connectivity on EEG rhythms, power spectral density and coherence among coupled neural populations: analysis with a neural mass model.

    Science.gov (United States)

    Zavaglia, Melissa; Astolfi, Laura; Babiloni, Fabio; Ursino, Mauro

    2008-01-01

    In the present work, a neural mass model consisting of four interconnected neural groups (pyramidal neurons, excitatory interneurons, inhibitory interneurons with slow synaptic kinetics, and inhibitory interneurons with fast synaptic kinetics) is used to investigate the mechanisms which cause the appearance of multiple rhythms in EEG spectra, and to assess how these rhythms can be affected by connectivity among different populations. In particular, we analyze a circuit, composed of three interconnected populations, each with a different synaptic kinetics (hence, with a different intrinsic rhythm). Results demonstrate that a single population can exhibit many different simultaneous rhythms, provided that some of these come from external sources (for instance, from remote regions). Analysis of coherence, and of the position of peaks in power spectral density, reveals important information on the possible connections among populations, especially useful to follow temporal changes in connectivity. Subsequently, the model is validated by comparing the power spectral density simulated in one population with that computed in the controlateral cingulated cortex (a region involved in motion preparation) during a right foot movement task in four normal subjects. The model is able to simulate real spectra quite well with only moderate parameter changes within the subject. In perspective, the results may be of value for a deeper comprehension of mechanism causing EEGs rhythms, for the study of brain connectivity and for the test of neurophysiological hypotheses.

  1. Pep-Calc.com: a set of web utilities for the calculation of peptide and peptoid properties and automatic mass spectral peak assignment.

    Science.gov (United States)

    Lear, Sam; Cobb, Steven L

    2016-03-01

    The ability to calculate molecular properties such as molecular weights, isoelectric points, and extinction coefficients is vital for scientists using and/or synthesizing peptides and peptoids for research. A suite of two web utilities: Peptide Calculator and Peptoid Calculator, available free at http://www.pep-calc.com, are presented. Both tools allow the calculation of peptide/peptoid chemical formulae and molecular weight, ChemDraw structure file export and automatic assignment of mass spectral peaks to deletion sequences and metal/protecting group adducts. Peptide Calculator also provides a calculated isoelectric point, molar extinction coefficient, graphical peptide charge summary and β-strand contiguity profile (for aggregation-prone sequences), indicating potential regions of synthesis difficulty. In addition to the unique automatic spectral assignment features offered across both utilities, Peptoid Calculator represents a first-of-a-kind resource for researchers in the field of peptoid science. With a constantly expanding database of over 120 amino acids, non-natural peptide building blocks and peptoid building blocks, it is anticipated that Pep-Calc.com will act as a valuable asset to those working on the synthesis and/or application of peptides and peptoids in the biophysical and life sciences fields.

  2. The HIFI spectral survey of AFGL2591 (CHESS). I. Highly excited linear rotor molecules in the high-mass protostellar envelope

    CERN Document Server

    van der Wiel, M H D; van der Tak, F F S; Kazmierczak, M; Ceccarelli, C

    2013-01-01

    We aim to reveal the gas energetics in the circumstellar environment of the prototypical high-mass protostellar object AFGL2591 using space-based far-infrared observations of linear rotor molecules. Rotational spectral line signatures of CO, HCO+, CS, HCN and HNC from a 490-1240 GHz survey with Herschel/HIFI, complemented by ground-based JCMT and IRAM 30m spectra, cover transitions with E(up)/k between 5 and ~300 K (750K for 12C16O, using selected frequency settings up to 1850 GHz). The resolved spectral line profiles are used to separate and study various kinematic components. The line profiles show two emission components, the widest and bluest of which is attributed to an approaching outflow and the other to the envelope. We find evidence for progressively more redshifted and wider line profiles from the envelope gas with increasing energy level, qualitatively explained by residual outflow contribution picked up in the systematically decreasing beam size. Integrated line intensities for each species decrea...

  3. Spectral-Timing Analysis of the Lower kHz QPO in the Low-Mass X-ray Binary Aquila X-1

    CERN Document Server

    Troyer, Jon S

    2016-01-01

    Spectral-timing products of kilohertz quasi-periodic oscillations (kHz QPOs) in low-mass X-ray binary (LMXB) systems, including energy- and frequency-dependent lags, have been analyzed previously in 4U 1608-52, 4U 1636-53, and 4U 1728-34. Here, we study the spectral-timing properties of the lower kHz QPO of the neutron star LMXB Aquila X-1 for the first time. We compute broadband energy lags, as well as energy-dependent lags and the covariance spectrum using data from the Rossi X-ray Timing Explorer (RXTE). We find very similar characteristics to other previously studied systems, including soft lags of $\\sim$30 $\\mu$s between the 3.0 - 8.0 keV and 8.0 - 20.0 keV energy bands at the average QPO frequency. We also find lags that show a nearly monotonic trend with energy, with the highest energy photons arriving first. The covariance spectrum of the lower kHz QPO is well fit by a thermal Comptonization model, though we find a higher seed photon temperature compared to the mean spectrum, which was also seen in Pe...

  4. Spectral and Timing Properties of the Low-mass X-ray Binary 4U 0614+09 with XMM-Newton

    CERN Document Server

    Méndez, M; Paerels, F B S; Cottam, Jean

    2002-01-01

    4U 0614+09 is a low-mass X-ray binary with a weakly magnetized neutron star primary. It shows variability on time scales that range from years down to ~0.8 milliseconds. Before the Chandra and XMM-Newton era, emission features around 0.7 keV have been reported from this source, but recent Chandra observations failed to detect them. Instead, these observations suggest an overabundance of Ne in the absorbing material, which may be common to ultracompact (P_{orb} \\simless 1 hour) systems with a neon-rich degenerate dwarf secondary. We observed 4U 0614+09 with XMM-Newton in March 2001. Here we present the energy spectra, both from the RGS and EPIC cameras, and the Fourier power spectra from EPIC high-time resolution light curves, which we use to characterize the spectral state of the source.

  5. Library Automation

    OpenAIRE

    Dhakne, B. N.; Giri, V. V.; Waghmode, S. S.

    2010-01-01

    New technologies library provides several new materials, media and mode of storing and communicating the information. Library Automation reduces the drudgery of repeated manual efforts in library routine. By use of library automation collection, Storage, Administration, Processing, Preservation and communication etc.

  6. Multivariate Statistical Analysis of Orthogonal Mass Spectral Data for the Identification of Chemical Attribution Signatures of 3-Methylfentanyl

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, B. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Valdez, C. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DeHope, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Spackman, P. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sanner, R. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Martinez, H. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Williams, A. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-11-28

    Critical to many modern forensic investigations is the chemical attribution of the origin of an illegal drug. This process greatly relies on identification of compounds indicative of its clandestine or commercial production. The results of these studies can yield detailed information on method of manufacture, sophistication of the synthesis operation, starting material source, and final product. In the present work, chemical attribution signatures (CAS) associated with the synthesis of the analgesic 3- methylfentanyl, N-(3-methyl-1-phenethylpiperidin-4-yl)-N-phenylpropanamide, were investigated. Six synthesis methods were studied in an effort to identify and classify route-specific signatures. These methods were chosen to minimize the use of scheduled precursors, complicated laboratory equipment, number of overall steps, and demanding reaction conditions. Using gas and liquid chromatographies combined with mass spectrometric methods (GC-QTOF and LC-QTOF) in conjunction with inductivelycoupled plasma mass spectrometry (ICP-MS), over 240 distinct compounds and elements were monitored. As seen in our previous work with CAS of fentanyl synthesis the complexity of the resultant data matrix necessitated the use of multivariate statistical analysis. Using partial least squares discriminant analysis (PLS-DA), 62 statistically significant, route-specific CAS were identified. Statistical classification models using a variety of machine learning techniques were then developed with the ability to predict the method of 3-methylfentanyl synthesis from three blind crude samples generated by synthetic chemists without prior experience with these methods.

  7. Qualitative and quantitative top-down mass spectral analysis of crustacean hyperglycemic hormones in response to feeding.

    Science.gov (United States)

    Jia, Chenxi; Yu, Qing; Wang, Jingxin; Li, Lingjun

    2014-05-01

    An efficient pipeline for peptide discovery accelerates peptidomic analysis and facilitates a better understanding of the functional roles of neuropeptides. However, qualitative and quantitative analysis of large neuropeptides is challenging due to the bigger molecular sizes, multiple PTMs, and interference by homologous isoforms. Herein, we refined two methodologies in the pipeline for highly confident and efficient MS-based peptide discovery. For the qualitative analysis, the so-called "high resolution/accurate mass" measurement on Orbitrap mass spectrometers was integrated with computer-assisted homology search, which was successfully applied to decipher the substituted amino acid residues in large neuropeptides by referring to homologous sequences. For the quantitative analysis, a new isotopic labeling-assisted top-down MS strategy was developed, which enabled direct monitoring of the abundance changes of endogenous large neuropeptides. By using the refined peptide discovery pipeline, one novel crustacean hyperglycemic hormone (CHH) from the Dungeness crab sinus glands was confidently identified and de novo sequenced, and its relative abundance was quantified. Comparative analysis of CHHs in unfed and fed crabs revealed that the peptide abundance in the sinus glands was significantly increased after food intake, suggesting that the release of CHHs might be altered by feeding behavior. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Sulphur-containing compounds in the essential oil of Ferula alliacea roots and their mass spectral fragmentation patterns.

    Science.gov (United States)

    Kasaian, Jamal; Asili, Javad; Iranshahi, Mehrdad

    2016-10-01

    Context GC-MS analysis is the best way to characterize volatile sulphur-containing compounds. Ferula (Apiaceae) is a genus of perennial herbs. Due to the occurrence of essential oils or oleoresins in the Ferula species, these plants usually possess strong aromatic scent. Terpenoid compounds were the most abundant constituents of Ferula oils, however, in some of Ferula species, the essential oils were dominated by volatile sulphur-containing compounds. Objectives Ferula alliacea Boiss. is considered one of the sources of the oleo-gum-resin asafoetida. In this study, we analyzed the hydrodistilled essential oil from its dried roots and provide new data about retention indices and mass fragmentation patterns of some volatile sulphur-containing compounds that are useful for future studies on this class of compounds. Materials and methods The roots of F. alliacea were collected during the flowering stage of plant, from Bezgh, Kashmar to Neishabour road, Khorasan-Razavi province, Iran, in June 2012. The oil was obtained by hydrodistillation using a Clevenger apparatus and analyzed by GC-MS. Results This is the first report on phytochemical analysis of F. alliacea roots. Seventy-six components, representing 99.5% of the oil, were characterized. The major components were 10-epi-γ-eudesmol (22.3%), valerianol (12.5%), hinesol (8.3%), guaiol (7.3%) and Z-propenyl-sec-butyl trisulphide (6.5%). Predominant mass fragment ions of the identified sulphur-containing compounds are explained in this paper. Conclusion The volatile oil of F. alliacea mostly contains oxygenated sesquiterpenes, however, its odour was dominated by sulphur-containing compounds. The most abundant sulphur-containing compound includes Z-propenyl-sec-butyl trisulphide (6.5%).

  9. Herschel/PACS far-IR spectral imaging of a jet from an intermediate mass protostar in the OMC-2 region

    Science.gov (United States)

    González-García, B.; Manoj, P.; Watson, D. M.; Vavrek, R.; Megeath, S. T.; Stutz, A. M.; Osorio, M.; Wyrowski, F.; Fischer, W.; Tobin, J. J.; Sánchez-Portal, M.; Diaz Rodriguez, A. K.; Wilson, T. L.

    2016-11-01

    We present the first detection of a jet in the far-IR [O I] lines from an intermediate mass protostar. This jet was detected in a Herschel/PACS spectral mapping study in the [O I] lines of OMC-2 FIR 3 and FIR 4, two of the most luminous protostars in Orion outside of the Orion Nebula. The spatial morphology of the fine structure line emission reveals the presence of an extended photodissociation region (PDR) and a narrow, but intense jet connecting the two protostars. The jet seen in [O I] emission is spatially aligned with the Spitzer/IRAC 4.5 μm jet and the CO (6-5) molecular outflow centered on FIR 3. The mass-loss rate derived from the total [O I] 63 μm line luminosity of the jet is 7.7 × 10-6M⊙ yr-1, more than an order of magnitude higher than that measured for typical low-mass class 0 protostars. The implied accretion luminosity is significantly higher than the observed bolometric luminosity of FIR 4, indicating that the [O I] jet is unlikely to be associated with FIR 4. We argue that the peak line emission seen toward FIR 4 originates in the terminal shock produced by the jet driven by FIR 3. The higher mass-loss rate that we find for FIR 3 is consistent with the idea that intermediate-mass protostars drive more powerful jets than their low-mass counterparts. Our results also call into question the nature of FIR 4. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.The final reduced Herschel data used in this paper (FITS) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/596/A26

  10. Probing small-scale cosmological fluctuations with the 21 cm forest: effects of neutrino mass, running spectral index and warm dark matter

    CERN Document Server

    Shimabukuro, Hayato; Inoue, Susumu; Yokoyama, Shuichiro

    2014-01-01

    Although the cosmological paradigm based on cold dark matter and adiabatic, nearly scale-invariant primordial fluctuations is consistent with a wide variety of existing observations, it has yet to be sufficiently tested on scales smaller than those of massive galaxies, and various alternatives have been proposed that differ significantly in the consequent small-scale power spectrum (SSPS) of large-scale structure. Here we show that a powerful probe of the SSPS at $k\\gtrsim 10$ Mpc$^{-1}$ can be provided by the 21 cm forest, that is, systems of narrow absorption lines due to intervening, cold neutral hydrogen in the spectra of high-redshift background radio sources in the cosmic reionization epoch. Such features are expected to be caused predominantly by collapsed gas in starless minihalos, whose mass function can be very sensitive to the SSPS. As specific examples, we consider the effects of neutrino mass, running spectral index (RSI) and warm dark matter (WDM) on the SSPS, and evaluate the expected distribut...

  11. A broadband X-ray spectral study of the intermediate-mass black hole candidate M82 X-1 with NuSTAR, Chandra and Swift

    CERN Document Server

    Brightman, Murray; Barret, Didier; Davis, Shane W; Fürst, Felix; Madsen, Kristin K; Middleton, Matthew; Miller, Jon M; Stern, Daniel; Tao, Lian; Walton, Dominic J

    2016-01-01

    M82 X-1 is one of the brightest ultraluminous X-ray sources (ULXs) known, which, assuming Eddington-limited accretion and other considerations, makes it one of the best intermediate-mass black hole (IMBH) candidates. However, the ULX may still be explained by super-Eddington accretion onto a stellar-remnant black hole. We present simultaneous NuSTAR, Chandra and Swift/XRT observations during the peak of a flaring episode with the aim of modeling the emission of M82 X-1 and yielding insights into its nature. We find that thin-accretion disk models all require accretion rates at or above the Eddington limit in order to reproduce the spectral shape, given a range of black hole masses and spins. Since at these high Eddington ratios the thin-disk model breaks down due to radial advection in the disk, we discard the results of the thin-disk models as unphysical. We find that the temperature profile as a function of disk radius ($T(r)\\propto r^{-p}$) is significantly flatter ($p=0.55^{+ 0.07}_{- 0.04}$) than expecte...

  12. Mass Spectral Enhanced Detection of Ubls Using SWATH Acquisition: MEDUSA—Simultaneous Quantification of SUMO and Ubiquitin-Derived Isopeptides

    Science.gov (United States)

    Griffiths, John R.; Chicooree, Navin; Connolly, Yvonne; Neffling, Milla; Lane, Catherine S.; Knapman, Thomas; Smith, Duncan L.

    2014-05-01

    Protein modification by ubiquitination and SUMOylation occur throughout the cell and are responsible for numerous cellular functions such as apoptosis, DNA replication and repair, and gene transcription. Current methods for the identification of such modifications using mass spectrometry predominantly rely upon tryptic isopeptide tag generation followed by database searching with in vitro genetic mutation of SUMO routinely required. We have recently described a novel approach to ubiquitin and SUMO modification detection based upon the diagnostic a' and b' ions released from the isopeptide tags upon collision-induced dissociation of reductively methylated Ubl isopeptides (RUbI) using formaldehyde. Here, we significantly extend those studies by combining data-independent acquisition (DIA) with alternative labeling reagents to improve diagnostic ion coverage and enable relative quantification of modified peptides from both MS and MS/MS signals. Model synthetic ubiquitin and SUMO-derived isopeptides were labeled with mTRAQ reagents (Δ0, Δ4, and Δ8) and subjected to LC-MS/MS with SWATH acquisition. Novel diagnostic ions were generated upon CID, which facilitated the selective detection of these modified peptides. Simultaneous MS-based and MS/MS-based relative quantification was demonstrated for both Ub and SUMO-derived isopeptides across three channels in a background of mTRAQ-labeled Escherichia coli digest.

  13. Herschel/HIFI observations of spectrally resolved methylidyne signatures toward the high-mass star forming core NGC6334I

    CERN Document Server

    van der Wiel, M H D; Lis, D C; Bergin, E A; Comito, C; Emprechtinger, M; Schilke, P; Caux, E; Ceccarelli, C; Baudry, A; Goldsmith, P F; Herbst, E; Langer, W; Lord, S; Neufeld, D; Pearson, J; Philips, T; Rolffs, R; Yorke, H; Bacmann, A; Benedettini, M; Blake, G A; Boogert, A; Bottinelli, S; Cabrit, S; Caselli, P; Castets, A; Cernicharo, J; Codella, C; Coutens, A; Crimier, N; Demyk, K; Dominik, C; Encrenaz, P; Falgarone, E; Fuente, A; Gerin, M; Helmich, F; Hennebelle, P; Henning, T; Hily-Blant, P; Jacq, T; Kahane, C; Kama, M; Klotz, A; Lefloch, B; Lorenzani, A; Maret, S; Melnick, G; Nisini, B; Pacheco, S; Pagani, L; Parise, B; Salez, M; Saraceno, P; Schuster, K; Tielens, A G G M; Vastel, C; Viti, S; Wakelam, V; Walters, A; Wyrowski, F; Edwards, K; Zmuidzinas, J; Morris, P; Samoska, L A; Teyssier, D

    2010-01-01

    In contrast to extensively studied dense star forming cores, little is known about diffuse gas surrounding star forming regions. We aim to study molecular gas in the high-mass star forming region NGC6334I, including diffuse, quiescent components which are inconspicuous in widely used molecular tracers such as CO. We present Herschel/HIFI observations of CH toward NGC6334I observed as part of the CHESS Key Program. HIFI resolves the hyperfine components of its J=3/2-1/2 transition, observed in emission as well as in absorption. The CH emission appears close to the systemic velocity of NGC6334I, while a linewidth of 3 km/s is smaller than previously observed in dense gas tracers such as NH3 and SiO. The CH abundance in the hot core is 7 10^-11, two to three orders of magnitude lower than in diffuse clouds. While other studies find distinct outflows in, e.g., CO and H2O toward NGC6334I, we do not detect outflow signatures in CH. To explain the absorption signatures, at least two absorbing components are needed a...

  14. Mass spectral characterisation of a polar, esterified fraction of an organic extract of an oil sands process water.

    Science.gov (United States)

    Rowland, S J; Pereira, A S; Martin, J W; Scarlett, A G; West, C E; Lengger, S K; Wilde, M J; Pureveen, J; Tegelaar, E W; Frank, R A; Hewitt, L M

    2014-11-15

    Characterising complex mixtures of organic compounds in polar fractions of heavy petroleum is challenging, but is important for pollution studies and for exploration and production geochemistry. Oil sands process-affected water (OSPW) stored in large tailings ponds by Canadian oil sands industries contains such mixtures. A polar OSPW fraction was obtained by silver ion solid-phase extraction with methanol elution. This was examined by numerous methods, including electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) and ultra-high-pressure liquid chromatography (uHPLC)/Orbitrap MS, in multiple ionisation and MS/MS modes. Compounds were also synthesised for comparison. The major ESI ionisable compounds detected (+ion mode) were C15-28 SO3 species with 3-7 double bond equivalents (DBE) and C27-28 SO5 species with 5 DBE. ESI-MS/MS collision-induced losses were due to water, methanol, water plus methanol and water plus methyl formate, typical of methyl esters of hydroxy acids. Once the fraction was re-saponified, species originally detected by positive ion MS, could be detected only by negative ion MS, consistent with their assignment as sulphur-containing hydroxy carboxylic acids. The free acid of a keto dibenzothiophene alkanoic acid was added to an unesterified acid extract of OSPW in known concentrations as a putative internal standard, but attempted quantification in this way proved unreliable. The results suggest the more polar acidic organic SO3 constituents of OSPW include C15-28  S-containing, alicyclic and aromatic hydroxy carboxylic acids. SO5 species are possibly sulphone analogues of these. The origin of such compounds is probably via further biotransformation (hydroxylation) of the related S-containing carboxylic acids identified previously in a less polar OSPW fraction. The environmental risks, corrosivity and oil flow assurance effects should be easier to assess, given that partial structures are now known

  15. Application of parallel liquid chromatography/mass spectrometry for high throughput microsomal stability screening of compound libraries.

    Science.gov (United States)

    Xu, Rongda; Nemes, Csaba; Jenkins, Kelly M; Rourick, Robyn A; Kassel, Daniel B; Liu, Charles Z C

    2002-02-01

    Solution-phase and solid-phase parallel synthesis and high throughput screening have enabled biologically active and selective compounds to be identified at an unprecedented rate. The challenge has been to convert these hits into viable development candidates. To accelerate the conversion of these hits into lead development candidates, early assessment of the physicochemical and pharmacological properties of these compounds is being made. In particular, in vitro absorption, distribution, metabolism, and elimination (ADME) assays are being conducted at earlier and earlier stages of discovery with the goal of reducing the attrition rate of these potential drug candidates as they progress through development. In this report, we present an eight-channel parallel liquid chromatography/mass spectrometry (LC/MS) system in combination with custom Visual Basic and Applescript automated data processing applications for high throughput early ADME. The parallel LC/MS system was configured with one set of gradient LC pumps and an eight-channel multiple probe autosampler. The flow was split equivalently into eight streams before the multiple probe autosampler and recombined after the eight columns and just prior to the mass spectrometer ion source. The system was tested for column-to-column variation and for reproducibility over a 17 h period (approximately 500 injections per column). The variations in retention time and peak area were determined to be less than 2 and 10%, respectively, in both tests. The parallel LC/MS system described permits time-course microsomal incubations (t(o), t5, t15, t30) to be measured in triplicate and enables estimations of t 1/2 microsomal stability. The parallel LC/MS system is capable of analyzing up to 240 samples per hour and permits the complete profiling up to two microtiter plates of compounds per day (i.e., 176 test substrate compounds + sixteen controls).

  16. Library Computing

    Science.gov (United States)

    Library Computing, 1985

    1985-01-01

    Special supplement to "Library Journal" and "School Library Journal" covers topics of interest to school, public, academic, and special libraries planning for automation: microcomputer use, readings in automation, online searching, databases of microcomputer software, public access to microcomputers, circulation, creating a…

  17. Digital Libraries

    CERN Document Server

    Papy, Fabrice

    2008-01-01

    Of vital interest to all librarians and information specialists, this book presents all aspects of the effects of digitization of today's and tomorrow's libraries. From social to technical issues, Digital Libraries includes chapters on the growth of the role of librarian, the reader experience, cataloging, search engines, OPAC, law, ergonomic studies, and the future of libraries.

  18. Biomedical Libraries

    Science.gov (United States)

    Pizer, Irwin H.

    1978-01-01

    Biomedical libraries are discussed as a distinct and specialized group of special libraries and their unique services and user interactions are described. The move toward professional standards, as evidenced by the Medical Library Association's new certification program, and the current state of development for a new section of IFLA established…

  19. Dual-Energy Contrast-Enhanced Spectral Mammography: Enhancement Analysis on BI-RADS 4 Non-Mass Microcalcifications in Screened Women

    Science.gov (United States)

    Cheung, Yun-Chung; Juan, Yu-Hsiang; Lin, Yu-Ching; Lo, Yung-Feng; Tsai, Hsiu-Pei; Ueng, Shir-Hwa; Chen, Shin-Cheh

    2016-01-01

    Background Mammography screening is a cost-efficient modality with high sensitivity for detecting impalpable cancer with microcalcifications, and results in reduced mortality rates. However, the probability of finding microcalcifications without associated cancerous masses varies. We retrospectively evaluated the diagnosis and cancer probability of the non-mass screened microcalcifications by dual-energy contrast-enhanced spectral mammography (DE-CESM). Patients and Methods With ethical approval from our hospital, we enrolled the cases of DE-CESM for analysis under the following inclusion criteria: (1) referrals due to screened BI-RADS 4 microcalcifications; (2) having DE-CESM prior to stereotactic biopsy; (3) no associated mass found by sonography and physical examination; and (4) pathology-based diagnosis using stereotactic vacuum-assisted breast biopsy. We analyzed the added value of post-contrast enhancement on DE-CESM. Results A total of 94 biopsed lesions were available for analysis in our 87 women, yielding 27 cancers [19 ductal carcinoma in situ (DCIS), and 8 invasive ductal carcinoma (IDC)], 32 pre-malignant and 35 benign lesions. Of these 94 lesions, 33 showed associated enhancement in DE-CESM while the other 61 did not. All 8 IDC (100%) and 16 of 19 DCIS (84.21%) showed enhancement, but the other 3 DCIS (15.79%) did not. Overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 88.89%, 86.56%, 72.72%, 95.08% and 87.24%, respectively. The performances of DE-CESM on both amorphous and pleomorphic microcalcifications were satisfactory (AUC 0.8 and 0.92, respectively). The pleomorphous microcalcifications with enhancement showed higher positive predictive value (90.00% vs 46.15%, p = 0.013) and higher cancer probability than the amorphous microcalcifications (46.3% VS 15.1%). The Odds Ratio was 4.85 (95% CI: 1.84–12.82). Conclusion DE-CESM might provide added value in assessing the non-mass screened breast

  20. Non-target screening of organic pollutants in sediments and sludges using gas chromatography-mass spectrometry and automated mass spectral deconvolution%气相色谱-质谱-自动质谱解卷积技术在沉积物和污泥中有机污染物非靶标筛查中的应用

    Institute of Scientific and Technical Information of China (English)

    王刚; 马慧莲; 王龙星; 陈吉平; 侯晓虹

    2015-01-01

    A screening method in the combination of ultrasonic extraction,gas chromatogra-phy-mass spectrometry detection and automated mass spectrometry deconvolution technique was developed for non-target screening of non-polar and weak polar pollutants in sediments and sludges. The samples were extracted by ultrasonication for 20 min using dichloromethane for three times. The extraction solutions were cleaned-up by gel permeation chromatography and a silica gel column,and then 3 g of copper powder was used to remove the sulfur by ultrasonica-tion for 10 min. Parallel experiments were carried out for 5 times and the RSDs were ranged from 5. 8% to 14. 9%. Automated mass spectral deconvolution &identification system( AMDIS) would improve the resolution of overlapping peaks,and identify the pure mass spectrum of the analytes in the cases of stronger background interference and co-extracted substances covering. Standard spectrum databases,such as NISTDRUG,NISTEPA,NISTFDA,Mass Spectral Library, etc,would qualitatively identify the organic pollutants in the samples. As a result,a total of 290 organic pollutants were identified,of which 190 and 153 pollutants were found in sediments and sludges,respectively. The identified pollutants included the Environmental Protection Agency (EPA)priority pollutants,pharmaceuticals,herbicides,antioxidants,intermediates,organic solvents and chemical raw materials. The proposed method is proved to be a promising one for non-target screening of complex matrix samples with the advantages of higher sensitivity and better repeatability.%以沉积物和污泥中非极性和弱极性有机污染物的非靶标筛查为目的,建立了一种超声波辅助提取-气相色谱-质谱结合自动解卷积技术的筛查方法。以二氯甲烷为溶剂超声波辅助提取样品3次,每次20 min,提取液经凝胶渗透色谱( GPC)和硅胶层析柱净化,再用3 g铜粉超声10 min除硫。前处理方法的重复性( RSD,n=5)为5.8

  1. Galaxy And Mass Assembly (GAMA): ugrizYJHK S\\'ersic luminosity functions and the cosmic spectral energy distribution by Hubble type

    CERN Document Server

    Kelvin, Lee S; Robotham, Aaron S G; Graham, Alister W; Phillipps, Steven; Agius, Nicola K; Alpaslan, Mehmet; Baldry, Ivan; Bamford, Steven P; Bland-Hawthorn, Joss; Brough, Sarah; Brown, Michael J I; Colless, Matthew; Conselice, Christopher J; Hopkins, Andrew M; Liske, Jochen; Loveday, Jon; Norberg, Peder; Pimbblet, Kevin A; Popescu, Cristina C; Prescott, Matthew; Taylor, Edward N; Tuffs, Richard J

    2014-01-01

    We report the morphological classification of 3727 galaxies from the Galaxy and Mass Assembly survey with M_r < -17.4 mag and in the redshift range 0.025 < z < 0.06 (2.1 x 10^5 Mpc^3 ) into E, S0-Sa, SB0-SBa, Sab-Scd, SBab-SBcd, Sd-Irr and little blue spheroid classes. Approximately 70% of galaxies in our sample are disk dominated systems, with the remaining ~30% spheroid dominated. We establish the robustness of our classifications, and use them to derive morphological-type luminosity functions and luminosity densities in the ugrizYJHK passbands, improving on prior studies that split by global colour or light profile shape alone. We find that the total galaxy luminosity function is best described by a double-Schechter function while the constituent morphological-type luminosity functions are well described by a single-Schechter function. These data are also used to derive the star-formation rate densities for each Hubble class, and the attenuated and unattenuated (corrected for dust) cosmic spectral...

  2. Nanoliter-volume protein enrichment, tryptic digestion, and partial separation based on isoelectric points by CE for MALDI mass spectral analysis.

    Science.gov (United States)

    Nesbitt, Chandra A; Jurcic, Kristina; Yeung, Ken K-C

    2008-01-01

    Sequence-specific proteolysis is an important part of protein identification by MS. Digestion of protein is commonly performed in-solution, in sample vials with volumes ranging from milli- to microliters. When digestion is performed with a sample volume below 1 microL, handling of solution and potential sample loss via adsorption become significant issues. In this report, a proof of concept for the digestion of a small volume protein solution inside a capillary was demonstrated using a discontinuous buffer system previously studied (Nesbitt, C. A., et al. J. Chromatogr. A 2005, 1073, 175-180). Upon voltage application, a pH junction was created by the discontinuous buffer. Using myoglobin as an example, the protein molecules were enriched at the junction with an estimated volume of a few nanoliters. A protease, trypsin, was then introduced to myoglobin at the junction by coenrichment to induce in-capillary digestion. The voltage application was then suspended to provide the necessary time (2 h) for the proteolysis to proceed. When completed, voltage application was resumed, and the discontinuous buffer reconcentrated the peptides formed from digestion. Importantly, the refocused peptides appeared to roughly elute according to their pIs, resulting in a partial separation. Direct sample deposition from capillary was performed to facilitate mass spectral analysis by MALDI. The partial separation, according to pI, offered the potential benefits of MALDI MS signal enhancement and provided supplementary pI information for peptide identity assignment.

  3. 由傳播媒介之內容探討圖書館與圖書館員的形象問題 Discussing the Librarian and Libraries' Image Problem by Analyzing the Content of Mass Media

    Directory of Open Access Journals (Sweden)

    Shau-chun Wu

    2003-06-01

    Full Text Available 本文探討圖書館與圖書館員的形象問題。首先討論圖書館及圖書館員形象問題探討的必要性,並分析圖書館及圖書館員常遭遇的形象問題;其次分析電視、電影、小說等大眾媒體中的圖書館及圖書館員形象,並尋找出圖書館及圖書館員形象低落的原因;最後則對圖書館及圖書館員在提昇形象上提出一些建議。This article discuses the problems of librarians and libraries negative image and low perception, and debates some arguments about librarians and libraries image problems.In the first part, it introduces some image problems that librarians and libraries always meet, and then analyzes the content of mass media associating with librarians and libraries, and tries to find the reasons for bad image about librarians and libraries.In the final part of this article, it will propose some suggestions for promoting the image and professional status.

  4. An Atlas of Galaxy Spectral Energy Distributions from the Ultraviolet to the Mid-Infrared

    CERN Document Server

    Brown, Michael J I; Smith, J -D T; da Cunha, Elisabete; Jarrett, T H; Imanishi, Masatoshi; Armus, Lee; Brandl, Bernhard R; Peek, J E G

    2013-01-01

    We present an atlas of 129 spectral energy distributions for nearby galaxies, with wavelength coverage spanning from the UV to the mid-infrared. Our atlas spans a broad range of galaxy types, including ellipticals, spirals, merging galaxies, blue compact dwarfs and luminous infrared galaxies. We have combined ground-based optical drift-scan spectrophotometry with infrared spectroscopy from Spitzer and Akari, with gaps in spectral coverage being filled using MAGPHYS spectral energy distribution models. The spectroscopy and models were normalized, constrained and verified with matched-aperture photometry measured from Swift, GALEX, SDSS, 2MASS, Spitzer and WISE images. The availability of 26 photometric bands allowed us to identify and mitigate systematic errors present in the data. Comparison of our spectral energy distributions with other template libraries and the observed colors of galaxies indicates that we have smaller systematic errors than existing atlases, while spanning a broader range of galaxy types...

  5. Library Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Carnegie Library of Pittsburgh locations including address, coordinates, phone number, square footage, and standard operating hours.

  6. America's Star Libraries: Top-Rated Libraries

    Science.gov (United States)

    Lance, Keith Curry; Lyons, Ray

    2009-01-01

    "Library Journal"'s national rating of public libraries, the "LJ" Index of Public Library Service 2009, Round 2, identifies 258 "star" libraries. Created by Keith Curry Lance and Ray Lyons and based on 2007 data from the IMLS, it rates 7,268 public libraries. The top libraries in each group get five, four, or three stars. All included libraries,…

  7. America's Star Libraries: Top-Rated Libraries

    Science.gov (United States)

    Lance, Keith Curry; Lyons, Ray

    2009-01-01

    "Library Journal"'s national rating of public libraries, the "LJ" Index of Public Library Service 2009, Round 2, identifies 258 "star" libraries. Created by Keith Curry Lance and Ray Lyons and based on 2007 data from the IMLS, it rates 7,268 public libraries. The top libraries in each group get five, four, or three stars. All included libraries,…

  8. Spectral Methods

    CERN Document Server

    Shen, Jie; Wang, Li-Lian

    2011-01-01

    Along with finite differences and finite elements, spectral methods are one of the three main methodologies for solving partial differential equations on computers. This book provides a detailed presentation of basic spectral algorithms, as well as a systematical presentation of basic convergence theory and error analysis for spectral methods. Readers of this book will be exposed to a unified framework for designing and analyzing spectral algorithms for a variety of problems, including in particular high-order differential equations and problems in unbounded domains. The book contains a large

  9. Library Use

    DEFF Research Database (Denmark)

    Konzack, Lars

    2012-01-01

    A seminar paper about a survey of role-playing games in public libraries combined with three cases and a presentation of a model.......A seminar paper about a survey of role-playing games in public libraries combined with three cases and a presentation of a model....

  10. Library Research.

    Science.gov (United States)

    Wright, Nancy Kirkpatrick

    This workbook, designed for a Library Research course at Yavapai College, provides 15 lessons in advanced library reference skills. Each lesson provides explanatory text and reinforcement exercises. After Lesson I introduces specialized dictionaries and encyclopedias (e.g., for foreign languages, medicine, music, economics, social sciences, and…

  11. Privatizing Libraries

    Science.gov (United States)

    Jerrard, Jane; Bolt, Nancy; Strege, Karen

    2012-01-01

    This timely special report from ALA Editions provides a succinct but comprehensive overview of the "privatization" of public libraries. It provides a history of the trend of local and state governments privatizing public services and assets, and then examines the history of public library privatization right up to the California…

  12. Privatizing Libraries

    Science.gov (United States)

    Jerrard, Jane; Bolt, Nancy; Strege, Karen

    2012-01-01

    This timely special report from ALA Editions provides a succinct but comprehensive overview of the "privatization" of public libraries. It provides a history of the trend of local and state governments privatizing public services and assets, and then examines the history of public library privatization right up to the California legislation…

  13. 由傳播媒介之內容探討圖書館與圖書館員的形象問題 Discussing the Librarian and Libraries' Image Problem by Analyzing the Content of Mass Media

    OpenAIRE

    2003-01-01

    本文探討圖書館與圖書館員的形象問題。首先討論圖書館及圖書館員形象問題探討的必要性,並分析圖書館及圖書館員常遭遇的形象問題;其次分析電視、電影、小說等大眾媒體中的圖書館及圖書館員形象,並尋找出圖書館及圖書館員形象低落的原因;最後則對圖書館及圖書館員在提昇形象上提出一些建議。This article discuses the problems of librarians and libraries negative image and low perception, and debates some arguments about librarians and libraries image problems.In the first part, it introduces some image problems that librarians and libraries always meet, and then analyzes the content of mass media associating with librarians and libraries, and tri...

  14. Studying stellar populations at high spectral resolution

    CERN Document Server

    Bruzual, Gustavo A

    2007-01-01

    I describe very briefly the new libraries of empirical spectra of stars covering wide ranges of values of the atmospheric parameters Teff, log g, [Fe/H], as well as spectral type, that have become available in the recent past, among them the HNGSL, MILES, UVES-POP, ELODIE, and the IndoUS libraries. I show the results of using the IndoUS and the HNGSL libraries, as well as an atlas of theoretical model atmospheres, to build population synthesis models. These libraries are complementary in spectral resolution and wavelength coverage, and will prove extremely useful to describe spectral features expected in galaxy spectra from the NUV to the NIR. The fits to observed galaxy spectra using simple and composite stellar population models are discussed.

  15. Academic Libraries

    Science.gov (United States)

    Library Journal, 1970

    1970-01-01

    Building data is given for the following academic libraries: (1) Rosary College, River Forest, Illinois; (2) Abilene Christian College, Abilene, Texas; (3) University of California, San Diego, La Jolla, California. (MF)

  16. Spectral Analysis

    CERN Document Server

    Cecconi, Jaures

    2011-01-01

    G. Bottaro: Quelques resultats d'analyse spectrale pour des operateurs differentiels a coefficients constants sur des domaines non bornes.- L. Garding: Eigenfuction expansions.- C. Goulaouic: Valeurs propres de problemes aux limites irreguliers: applications.- G. Grubb: Essential spectra of elliptic systems on compact manifolds.- J.Cl. Guillot: Quelques resultats recents en Scattering.- N. Schechter: Theory of perturbations of partial differential operators.- C.H. Wilcox: Spectral analysis of the Laplacian with a discontinuous coefficient.

  17. Spectral Reconstruction for Obtaining Virtual Hyperspectral Images

    Science.gov (United States)

    Perez, G. J. P.; Castro, E. C.

    2016-12-01

    Hyperspectral sensors demonstrated its capabalities in identifying materials and detecting processes in a satellite scene. However, availability of hyperspectral images are limited due to the high development cost of these sensors. Currently, most of the readily available data are from multi-spectral instruments. Spectral reconstruction is an alternative method to address the need for hyperspectral information. The spectral reconstruction technique has been shown to provide a quick and accurate detection of defects in an integrated circuit, recovers damaged parts of frescoes, and it also aids in converting a microscope into an imaging spectrometer. By using several spectral bands together with a spectral library, a spectrum acquired by a sensor can be expressed as a linear superposition of elementary signals. In this study, spectral reconstruction is used to estimate the spectra of different surfaces imaged by Landsat 8. Four atmospherically corrected surface reflectance from three visible bands (499 nm, 585 nm, 670 nm) and one near-infrared band (872 nm) of Landsat 8, and a spectral library of ground elements acquired from the United States Geological Survey (USGS) are used. The spectral library is limited to 420-1020 nm spectral range, and is interpolated at one nanometer resolution. Singular Value Decomposition (SVD) is used to calculate the basis spectra, which are then applied to reconstruct the spectrum. The spectral reconstruction is applied for test cases within the library consisting of vegetation communities. This technique was successful in reconstructing a hyperspectral signal with error of less than 12% for most of the test cases. Hence, this study demonstrated the potential of simulating information at any desired wavelength, creating a virtual hyperspectral sensor without the need for additional satellite bands.

  18. Stingray: Spectral-timing software

    Science.gov (United States)

    Huppenkothen, Daniela; Bachetti, Matteo; Stevens, Abigail L.; Migliari, Simone; Balm, Paul

    2016-08-01

    Stingray is a spectral-timing software package for astrophysical X-ray (and more) data. The package merges existing efforts for a (spectral-)timing package in Python and is composed of a library of time series methods (including power spectra, cross spectra, covariance spectra, and lags); scripts to load FITS data files from different missions; a simulator of light curves and event lists that includes different kinds of variability and more complicated phenomena based on the impulse response of given physical events (e.g. reverberation); and a GUI to ease the learning curve for new users.

  19. America's Star Libraries

    Science.gov (United States)

    Lyons, Ray; Lance, Keith Curry

    2009-01-01

    "Library Journal"'s new national rating of public libraries, the "LJ" Index of Public Library Service, identifies 256 "star" libraries. It rates 7,115 public libraries. The top libraries in each group get five, four, or three Michelin guide-like stars. All included libraries, stars or not, can use their scores to learn from their peers and improve…

  20. America's Star Libraries

    Science.gov (United States)

    Lyons, Ray; Lance, Keith Curry

    2009-01-01

    "Library Journal"'s new national rating of public libraries, the "LJ" Index of Public Library Service, identifies 256 "star" libraries. It rates 7,115 public libraries. The top libraries in each group get five, four, or three Michelin guide-like stars. All included libraries, stars or not, can use their scores to learn from their peers and improve…

  1. X-Ray Properties of K-Selected Galaxies at 0.5 Less than z Less than 2.0: Investigating Trends with Stellar Mass, Redshift and Spectral Type

    Science.gov (United States)

    Jones, Therese M.; Kriek, Mariska; vanDokkum, Peter G.; Brammer, Gabriel; Franx, Marijn; Greene, Jenny E.; Labbe, Ivo; Whitaker, Katherine E.

    2014-01-01

    We examine how the total X-ray luminosity correlates with stellar mass, stellar population, and redshift for a K-band limited sample of approximately 3500 galaxies at 0.5 mass, and perform an X-ray stacking analysis using the Chandra COSMOS data. We find that full band X-ray luminosity is primarily increasing with stellar mass, and at similar mass and spectral type is higher at larger redshifts. When comparing at the same stellar mass, we find that the X-ray luminosity is slightly higher for younger galaxies (i.e., weaker 4000 angstrom breaks), but the scatter in this relation is large. We compare the observed X-ray luminosities to those expected from low- and high-mass X-ray binaries (XRBs). For blue galaxies, XRBs can almost fully account for the observed emission, while for older galaxies with larger 4000 angstrom breaks, active galactic nuclei (AGN) or hot gas dominate the measured X-ray flux. After correcting for XRBs, the X-ray luminosity is still slightly higher in younger galaxies, although this correlation is not significant. AGN appear to be a larger component of galaxy X-ray luminosity at earlier times, as the hardness ratio increases with redshift. Together with the slight increase in X-ray luminosity this may indicate more obscured AGNs or higher accretion rates at earlier times.

  2. COMBINATORIAL LIBRARIES

    DEFF Research Database (Denmark)

    1997-01-01

    The invention provides a method for the production of a combinatorial library of compound of general formula (I) using solid phase methodologies. The cleavage of the array of immobilised compounds of the phthalimido type from the solid support matrix is accomplished by using an array of dinucleop......The invention provides a method for the production of a combinatorial library of compound of general formula (I) using solid phase methodologies. The cleavage of the array of immobilised compounds of the phthalimido type from the solid support matrix is accomplished by using an array...... of dinucleophiles, e.g. hydrazines (hydrazinolysis) or N-hydroxylamines, whereby a combinatorial dimension is introduced in the cleavage step. The invention also provides a compound library....

  3. Spectral Ranking

    CERN Document Server

    Vigna, Sebastiano

    2009-01-01

    This note tries to attempt a sketch of the history of spectral ranking, a general umbrella name for techniques that apply the theory of linear maps (in particular, eigenvalues and eigenvectors) to matrices that do not represent geometric transformations, but rather some kind of relationship between entities. Albeit recently made famous by the ample press coverage of Google's PageRank algorithm, spectral ranking was devised more than fifty years ago, almost exactly in the same terms, and has been studied in psychology and social sciences. I will try to describe it in precise and modern mathematical terms, highlighting along the way the contributions given by previous scholars.

  4. Spectral Tagging

    Energy Technology Data Exchange (ETDEWEB)

    Smartt, Heidi A. [Sandia National Laboratories (United States)

    2003-05-01

    This research examines the feasibility of spectral tagging, which involves modifying the spectral signature of a target, e.g. by mixing an additive with the target's paint. The target is unchanged to the human eye, but the tag is revealed when viewed with a spectrometer. This project investigates a layer of security that is not obvious, and therefore easy to conceal. The result is a tagging mechanism that is difficult to counterfeit. Uniquely tagging an item is an area of need in safeguards and security and non-proliferation. The powdered forms of the minerals lapis lazuli and olivine were selected as the initial test tags due to their availability and uniqueness in the visible to near-infrared spectral region. They were mixed with paints and applied to steel. In order to verify the presence of the tags quantitatively, the data from the spectrometer was input into unmixing models and signal detection algorithms. The mixture with the best results was blue paint mixed with lapis lazuli and olivine. The tag had a 0% probability of false alarm and a 100% probability of detection. The research proved that spectral tagging is feasible, although certain tag/paint mixtures are more detectable than others.

  5. Library rooms or Library halls

    Directory of Open Access Journals (Sweden)

    Alfredo Serrai

    2013-12-01

    Full Text Available Library Halls, understood as Renaissance and Baroque architectural creations, along with the furnishings and decorations, accomplish a cognitive task and serve to transmit knowledge. The design of these spaces based on the idea that they should reflect the merits and content of the collections housed within them, in order to prepare the mind of the reader to respect and admire the volumes. In accordance with this principle, in the fifteenth century library rooms had a basilican shape, with two or three naves, like churches, reflecting thus the spiritual value of the books contained there. Next to that inspiring function, library rooms had also the task of representing the entire logical and conceptual universe of human knowledge in a figurative way, including for this purpose also the and Kunst- und Wunderkammern, namely the collections of natural, artficial objects, and works of art. The importance of library rooms and their function was understood already in the early decades of the seventeenth century, as underlined in the treatise, Musei sive Bibliothecae tam privatae quam publicae Extructio, Instructio, Cura, Usus, written by the Jesuit Claude Clément and published in 1635. Almost the entire volume is dedicated to the decoration and ornamentation of the Saloni, and the function of the library is identified exclusively with the preservation and decoration of the collection, neglecting more specifically bibliographic aspects or those connected to library science. The architectural structure of the Saloni was destined to change in relation to two factors, namely the form of books, and the sources of light. As a consequence, from the end of the sixteenth century – or perhaps even before if one considers the fragments of the Library of Urbino belonging to Federico da Montefeltro – shelves and cabinets have been placed no longer in the center of the room, but were set against the walls. This new disposition of the furniture, surmounted by

  6. Mass Spectral Fragmentation of (S,S)-N,N′-Bis [1-(hydroxymethyl)alkyl]anthracene/Naphthalene-1,8-dicarboxamides under Electron Impact Ionization Conditions

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The mass spectrometric fragmentation of(S,S)-N,N′-bis[1-(hydroxymethyl)alkyl]anthracene/naphthalene-1,8-dicarboxamides was investigated with the aid of mass-analyzed ion kinetic energy spectrometry and the elemental compositions of important fragment ions were determined by accurate mass measurement under electron impact ionization conditions. All the compounds could eliminate formaldehyde. The [M-CH2O] ions could also eliminate imine, aziridine, aziridinone,2-amonoalkan-1-ol, water, and other fragments. Several cyclizations were observed under electron impact ionization.

  7. The SpeX Prism Library Analysis Toolkit: Design Considerations and First Results

    Science.gov (United States)

    Burgasser, Adam J.; Aganze, Christian; Escala, Ivana; Lopez, Mike; Choban, Caleb; Jin, Yuhui; Iyer, Aishwarya; Tallis, Melisa; Suarez, Adrian; Sahi, Maitrayee

    2016-01-01

    Various observational and theoretical spectral libraries now exist for galaxies, stars, planets and other objects, which have proven useful for classification, interpretation, simulation and model development. Effective use of these libraries relies on analysis tools, which are often left to users to develop. In this poster, we describe a program to develop a combined spectral data repository and Python-based analysis toolkit for low-resolution spectra of very low mass dwarfs (late M, L and T dwarfs), which enables visualization, spectral index analysis, classification, atmosphere model comparison, and binary modeling for nearly 2000 library spectra and user-submitted data. The SpeX Prism Library Analysis Toolkit (SPLAT) is being constructed as a collaborative, student-centered, learning-through-research model with high school, undergraduate and graduate students and regional science teachers, who populate the database and build the analysis tools through quarterly challenge exercises and summer research projects. In this poster, I describe the design considerations of the toolkit, its current status and development plan, and report the first published results led by undergraduate students. The combined data and analysis tools are ideal for characterizing cool stellar and exoplanetary atmospheres (including direct exoplanetary spectra observations by Gemini/GPI, VLT/SPHERE, and JWST), and the toolkit design can be readily adapted for other spectral datasets as well.This material is based upon work supported by the National Aeronautics and Space Administration under Grant No. NNX15AI75G. SPLAT code can be found at https://github.com/aburgasser/splat.

  8. Spectral Predictors

    Energy Technology Data Exchange (ETDEWEB)

    Ibarria, L; Lindstrom, P; Rossignac, J

    2006-11-17

    Many scientific, imaging, and geospatial applications produce large high-precision scalar fields sampled on a regular grid. Lossless compression of such data is commonly done using predictive coding, in which weighted combinations of previously coded samples known to both encoder and decoder are used to predict subsequent nearby samples. In hierarchical, incremental, or selective transmission, the spatial pattern of the known neighbors is often irregular and varies from one sample to the next, which precludes prediction based on a single stencil and fixed set of weights. To handle such situations and make the best use of available neighboring samples, we propose a local spectral predictor that offers optimal prediction by tailoring the weights to each configuration of known nearby samples. These weights may be precomputed and stored in a small lookup table. We show that predictive coding using our spectral predictor improves compression for various sources of high-precision data.

  9. Fourier resolved spectroscopy of 4U 1728-34: New Insights into Spectral and Temporal Properties of Low-Mass X-ray Binaries

    CERN Document Server

    Shrader, C R; Kazanas, D

    2007-01-01

    Using archival RXTE data we derive the 2-16 keV Fourier-resolved spectra of the Atoll source 4U 1728-34 in a sequence of its timing states as its low QPO frequency spans the range between 6 and 94 Hz. The increase in the QPO frequency accompanies a spectral transition of the source from its island to its banana states. The banana-states' Fourier-resolved spectra are well fitted by a single blackbody component with $kT \\sim 2-3$ keV depending on the source position in the color -- color diagram and the Fourier frequency, thus indicating that this spectral component is responsible for the source variability on these timescales. This result is in approximate agreement with similar behavior exhibited by the Z sources, suggesting that, as in that case, the boundary layer -- the likely source of the thermal component -- is supported by radiation pressure. Furthermore, it is found that the iron line at $\\sim$6.6 keV, clearly present in the averaged spectra, not apparent within the limitations of our measurements in ...

  10. Library news

    CERN Multimedia

    CERN Library

    2010-01-01

    The CERN Library has been providing electronic access to the "Techniques de l'Ingénieur" database for the past 8 months. As a reminder, this is a multidisciplinary database of over 4000 technical and scientific articles in French, covering a broad range of topics such as mechanical engineering, safety, electronics and the environment. In a few simple steps, you can create your own account, select the types of documents you are interested in and configure your settings so as to receive alerts when articles in your field of activity are published. You can now access this resource from outside CERN using the "remote access to electronic resources" service. Further information is available here. Direct access to the database. Remote access to electronic resources. If you have any questions or comments, don't hesitate to contact us at: library.desk@cern.ch.

  11. Library Benchmarking

    Directory of Open Access Journals (Sweden)

    Wiji Suwarno

    2017-02-01

    Full Text Available The term benchmarking has been encountered in the implementation of total quality (TQM or in Indonesian termed holistic quality management because benchmarking is a tool to look for ideas or learn from the library. Benchmarking is a processof measuring and comparing for continuous business process of systematic and continuous measurement, the process of measuring and comparing for continuous business process of an organization to get information that can help these organization improve their performance efforts.

  12. The PSIMECX medium-energy neutron activation cross-section library. Part II: Calculational methods for light to medium mass nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Atchison, F.

    1998-09-01

    The PSIMECX library contains calculated nuclide production cross-sections from neutron-induced reactions in the energy range about 2 to 800 MeV in the following 72 stable isotopes of 24 elements: {sup 12}C, {sup 13}C, {sup 16}O, {sup 17}O, {sup 18}O, {sup 23}Na, {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 27}Al, {sup 28}Si, {sup 29}Si, {sup 30}Si, {sup 31}P, {sup 32}S, {sup 33}S, {sup 34}S, {sup 36}S, {sup 35}Cl, {sup 37}Cl, {sup 39}K, {sup 40}K, {sup 41}K, {sup 40}Ca, {sup 42}Ca, {sup 43}Ca, {sup 44}Ca, {sup 46}Ca, {sup 48}Ca, {sup 46}Ti, {sup 47}Ti, {sup 48}Ti, {sup 49}Ti, {sup 50}Ti, {sup 50}V, {sup 51}V, {sup 50}Cr, {sup 52}Cr, {sup 53}Cr, {sup 54}Cr, {sup 55}Mn, {sup 54}Fe, {sup 56}Fe, {sup 57}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 61}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 66}Zn, {sup 67}Zn, {sup 68}Zn, {sup 70}Zn, {sup 92}Mo, {sup 94}Mo, {sup 95}Mo, {sup 96}Mo, {sup 97}Mo, {sup 98}Mo, {sup 100}Mo, {sup 121}Sb, {sup 123}Sb, {sup 204}Pb, {sup 206}Pb, {sup 207}Pb, {sup 208}Pb, {sup 232}Th and {sup 238}U. The energy range covers essentially all transmutation channels other than capture. The majority of the selected elements are principal constituents of normal materials of construction used in and around accelerator facilities and the library is, first and foremost, designed to be a tool for the estimation of their activation in wide-band neutron fields. This second report, of a series of three, describes and discusses the calculational methods used for the stable isotopes up to and including {sup 123}Sb. The library itself has been described in the first report of the series and the treatment for the heavy nuclei is given in the third. (author)

  13. Mass spectral characteristics of the chlorinated disinfection byproduct 2,2,4-trichloro-5-methoxy-cyclopent-4-ene-1,3-dione

    Science.gov (United States)

    Gong, Huijuan; Bao, Yanchu; Yang, Jihong; Jiang, Qin; Chen, Zezhi

    2010-06-01

    The objective of this paper was to correct the mistakes of a previous interpretation of electron impact ionization (EI) mass spectrum of the chlorinated disinfection byproduct (DBP) in drinking water naming 2,2,4-trichloro-5-methoxy-cyclopent-4-ene-1,3-dione (TCMCD). Moreover the positive-ion chemical ionization (CI +) and electrospray ionization (ESI +) mass spectra were also studied. As the search of new chlorinated disinfection byproducts in drinking water is a challenge and researchers generally have to attempt to identify unknown chlorinated products generated from incompletely defined starting materials, fully understanding the mass spectra of this compound may do some help for the analysis of other unknown chlorinated disinfection byproducts.

  14. PSYM-WIDE: A Survey for Large-separation Planetary-mass Companions to Late Spectral Type Members of Young Moving Groups

    Science.gov (United States)

    Naud, Marie-Eve; Artigau, Étienne; Doyon, René; Malo, Lison; Gagné, Jonathan; Lafrenière, David; Wolf, Christian; Magnier, Eugene A.

    2017-09-01

    We present the results of a direct imaging survey for very large separation (>100 au), low-mass companions around 95 nearby young K5–L5 stars and brown dwarfs. They are high-likelihood candidates or confirmed members of the young (≲150 Myr) β Pictoris and AB Doradus moving groups (ABDMG) and the TW Hya, Tucana–Horologium, Columba, Carina, and Argus associations. Images in i\\prime and z\\prime filters were obtained with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South to search for companions down to an apparent magnitude of z\\prime ∼ 22–24 at separations ≳20″ from the targets and in the remainder of the wide 5.‧5 × 5.‧5 GMOS field of view. This allowed us to probe the most distant region where planetary-mass companions could be gravitationally bound to the targets. This region was left largely unstudied by past high-contrast imaging surveys, which probed much closer-in separations. This survey led to the discovery of a planetary-mass (9–13 {M}{Jup}) companion at 2000 au from the M3V star GU Psc, a highly probable member of ABDMG. No other substellar companions were identified. These results allowed us to constrain the frequency of distant planetary-mass companions (5–13 {M}{Jup}) to {0.84}-0.66+6.73% (95% confidence) at semimajor axes between 500 and 5000 au around young K5–L5 stars and brown dwarfs. This is consistent with other studies suggesting that gravitationally bound planetary-mass companions at wide separations from low-mass stars are relatively rare.

  15. Leveraging on Easy Java Simulation tool and open source computer simulation library to create interactive digital media for mass customization of high school physics curriculum

    CERN Document Server

    Wee, Loo Kang

    2012-01-01

    This paper highlights the diverse possibilities in the rich community of educators from the Conceptual Learning of Science (CoLoS) and Open Source Physics (OSP) movement to engage, enable and empower educators and students, to create interactive digital media through computer modeling. This concept revolves around a paradigmatic shift towards participatory learning through immersive computer modeling, as opposed to using technology for information transmission. We aim to engage high school educators to professionally develop themselves by creating and customizing simulations possible through Easy Java Simulation (Ejs) and its learning community. Ejs allows educators to be designers of learning environments through modifying source codes of the simulation. Educators can conduct lessons with students' using these interactive digital simulations and rapidly enhance the simulation through changing the source codes personally. Ejs toolkit, its library of simulations and growing community contributed simulation cod...

  16. Sample Analysis at Mars Organic Contaminants Library (SAM-OCL)

    Science.gov (United States)

    Garcia-Sanchez, Raul; Misra, Prabhakar; Canham, John; Mahaffy, Paul

    2013-04-01

    The Sample Analysis at Mars Organic Contaminants Library (SAM-OCL) was developed as one of several components for the Mars rover mission's Contamination Control Protocol. The purpose of SAM-OCL is to determine the Gas Chromatography-Mass Spectroscopy (GCMS) signals of different materials composing the Mars Science Laboratory rover. In turn, this allows us to determine which GCMS signals originate from terrestrial contamination or rover material outgassing. The GCMS spectral library has several supplemental components, of which its descriptor spreadsheets are the most important, aimed to make SAM-OCL easily and readily accessible to users in and out of the Mars rover mission. One spreadsheet describes the contaminants that can be found in each file, while the other describes the information regarding each file. The library, along with its supplemental materials, is useful from an organizational and practical sense. Through them we are able to organize large volumes of GCMS data while breaking down the components that each material sample is made off. This allows us easy and fast access to information that will be critical when doing analysis in the data that the SAM instrumentation will obtain.

  17. New high resolution synthetic stellar libraries for the Gaia Mission

    CERN Document Server

    Sordo, R; Bouret, J C; Brott, I; Edvardsson, B; Frémat, Y; Heber, U; Josselin, E; Kochukhov, O; Korn, A; Lanzafame, A; Martins, F; Schweitzer, A; Thévenin, F; Zorec, J

    2008-01-01

    High resolution synthetic stellar libraries are of fundamental importance for the preparation of the Gaia Mission. We present new sets of spectral stellar libraries covering two spectral ranges: 300 --1100 nm at 0.1 nm resolution, and 840 -- 890 nm at 0.001 nm resolution. These libraries span a large range in atmospheric parameters, from super-metal-rich to very metal-poor (-5.0 $<$[Fe/H]$<$+1.0), from cool to hot (\\teff=3000--50000 K) stars, including peculiar abundance variations. The spectral resolution, spectral type coverage and number of models represent a substantial improvement over previous libraries used in population synthesis models and in atmospheric analysis.

  18. Dormitory libraries: libraries in dormitories

    Directory of Open Access Journals (Sweden)

    Peter Pavletič

    2004-01-01

    Full Text Available Dormitory libries are not justly treated in Slovenia. They have a double purpose: to develop student literacy, especially reading, critical and creative competence and, moreover, to provide students with opportunities for learning and active spending of free-time. This is made possible by means of a good collection of expertly arranged library material, which is regulary updated and presented to its users, both students and tutors alike. A questionnaire has helped us to find out that libraries in secondary school dormitories carry out their work rather successfully, especially from the viewpoint of poor facilities. The major problems are, nevertheless, the appropriate qualifications of those who fill the posts of librarian and low financial resources. Therefore, such activities should be thoroughly analysed and reconsidered in terms of possible effective solutions, if we want to at least maintain them, let alone develop them.

  19. Libraries for users services in academic libraries

    CERN Document Server

    Alvite, Luisa

    2010-01-01

    This book reviews the quality and evolution of academic library services. It revises service trends offered by academic libraries and the challenge of enhancing traditional ones such as: catalogues, repositories and digital collections, learning resources centres, virtual reference services, information literacy and 2.0 tools.studies the role of the university library in the new educational environment of higher educationrethinks libraries in academic contextredefines roles for academic libraries

  20. The World of Public Relations: For Libraries.

    Science.gov (United States)

    Barber, Peggy

    Included in this manual are (1) a check list for developing and planning an effective library marketing program; (2) tips for writing library news releases; (3) tips for mass media marketing using radio and television; (4) a sample form for building a media file with information on specific radio and TV stations; (5) tips for planning a library…

  1. Cloud parallel processing of tandem mass spectrometry based proteomics data.

    Science.gov (United States)

    Mohammed, Yassene; Mostovenko, Ekaterina; Henneman, Alex A; Marissen, Rob J; Deelder, André M; Palmblad, Magnus

    2012-10-05

    Data analysis in mass spectrometry based proteomics struggles to keep pace with the advances in instrumentation and the increasing rate of data acquisition. Analyzing this data involves multiple steps requiring diverse software, using different algorithms and data formats. Speed and performance of the mass spectral search engines are continuously improving, although not necessarily as needed to face the challenges of acquired big data. Improving and parallelizing the search algorithms is one possibility; data decomposition presents another, simpler strategy for introducing parallelism. We describe a general method for parallelizing identification of tandem mass spectra using data decomposition that keeps the search engine intact and wraps the parallelization around it. We introduce two algorithms for decomposing mzXML files and recomposing resulting pepXML files. This makes the approach applicable to different search engines, including those relying on sequence databases and those searching spectral libraries. We use cloud computing to deliver the computational power and scientific workflow engines to interface and automate the different processing steps. We show how to leverage these technologies to achieve faster data analysis in proteomics and present three scientific workflows for parallel database as well as spectral library search using our data decomposition programs, X!Tandem and SpectraST.

  2. The 1 - 50 keV spectral and timing analysis of IGR J18027-2016: an eclipsing, high mass X-ray binary

    CERN Document Server

    Hill, A B; Knigge, C; Bazzano, A; Bélanger, G; Bird, A J; Dean, A J; Galache, J L; Malizia, A; Renaud, M; Stephen, J; Ubertini, P

    2005-01-01

    We report the association of the INTEGRAL source IGR J18027-2016 with the BeppoSAX source SAX J1802.7-2017. IGR J18027-2016 is seen to be a weak, persistent source by the IBIS/ISGRI instrument on board INTEGRAL with an average source count rate of 0.55 counts s^-1 (~6.1 mCrab) in the 20-40 keV band. Timing analysis performed on the ISGRI data identifies an orbital period of 4.5696 +/- 0.0009 days and gives an ephemeris of mid-eclipse as, T{mid} = 52931.37 +/- 0.04 MJD. Re-analysis of archival BeppoSAX data has provided a mass function for the donor star, f(m) = 16 +/- 1 M{sun} and a projected semimajor axis of a{x}sin{i} = 68 +/- 1 lt-s. We conclude that the donor is an OB-supergiant with a mass of 18.8-29.3 M{sun} and a radius of 15.0-23.4 R{sun}. Spectra obtained by XMM-Newton and ISGRI indicate a high hydrogen column density of NH = 6.8 x 10^22 cm^-2, which suggests intrinsic absorption. The source appears to be a high mass X-ray binary with the neutron star emitting X-rays through wind-fed accretion while...

  3. Spectral Energy Distributions of Young Stars in IC 348: The Role of Disks in Angular Momentum Evolution of Young, Low-Mass Stars

    CERN Document Server

    Blanc, Thompson S Le; Stassun, Keivan G

    2011-01-01

    Theoretical work suggests that a young star's angular momentum and rotation rate may be strongly influenced by magnetic interactions with its circumstellar disk. A generic prediction of these 'disk-locking' (DL) theories is that a disk-locked star will be forced to co-rotate with the Keplerian angular velocity of the inner edge of the disk. These theories have also been interpreted to suggest a correlation between young stars' rotation periods and the structural properties of their disks, such that slowly rotating stars possess close-in disks that enforce the star's slow rotation, whereas rapidly rotating stars possess anemic or evacuated inner disks that are unable to brake the stars and they spin up as they contract. To test these expectations, we model the SEDs of 33 young stars in IC 348 with known rotation periods and infrared excesses indicating the presence of disks. For each star, we match the observed spectral energy distribution, typically sampling 0.6-8.0 \\mum, to a grid of 200,000 pre-computed sta...

  4. Organization of GC/MS and LC/MS metabolomics data into chemical libraries

    Directory of Open Access Journals (Sweden)

    DeHaven Corey D

    2010-10-01

    Full Text Available Abstract Background Metabolomics experiments involve generating and comparing small molecule (metabolite profiles from complex mixture samples to identify those metabolites that are modulated in altered states (e.g., disease, drug treatment, toxin exposure. One non-targeted metabolomics approach attempts to identify and interrogate all small molecules in a sample using GC or LC separation followed by MS or MSn detection. Analysis of the resulting large, multifaceted data sets to rapidly and accurately identify the metabolites is a challenging task that relies on the availability of chemical libraries of metabolite spectral signatures. A method for analyzing spectrometry data to identify and Quantify Individual Components in a Sample, (QUICS, enables generation of chemical library entries from known standards and, importantly, from unknown metabolites present in experimental samples but without a corresponding library entry. This method accounts for all ions in a sample spectrum, performs library matches, and allows review of the data to quality check library entries. The QUICS method identifies ions related to any given metabolite by correlating ion data across the complete set of experimental samples, thus revealing subtle spectral trends that may not be evident when viewing individual samples and are likely to be indicative of the presence of one or more otherwise obscured metabolites. Results LC-MS/MS or GC-MS data from 33 liver samples were analyzed simultaneously which exploited the inherent biological diversity of the samples and the largely non-covariant chemical nature of the metabolites when viewed over multiple samples. Ions were partitioned by both retention time (RT and covariance which grouped ions from a single common underlying metabolite. This approach benefitted from using mass, time and intensity data in aggregate over the entire sample set to reject outliers and noise thereby producing higher quality chemical identities. The

  5. Mass spectrometry–based relative quantification of proteins in precatalytic and catalytically active spliceosomes by metabolic labeling (SILAC), chemical labeling (iTRAQ), and label-free spectral count

    Science.gov (United States)

    Schmidt, Carla; Grønborg, Mads; Deckert, Jochen; Bessonov, Sergey; Conrad, Thomas; Lührmann, Reinhard; Urlaub, Henning

    2014-01-01

    The spliceosome undergoes major changes in protein and RNA composition during pre-mRNA splicing. Knowing the proteins—and their respective quantities—at each spliceosomal assembly stage is critical for understanding the molecular mechanisms and regulation of splicing. Here, we applied three independent mass spectrometry (MS)–based approaches for quantification of these proteins: (1) metabolic labeling by SILAC, (2) chemical labeling by iTRAQ, and (3) label-free spectral count for quantification of the protein composition of the human spliceosomal precatalytic B and catalytic C complexes. In total we were able to quantify 157 proteins by at least two of the three approaches. Our quantification shows that only a very small subset of spliceosomal proteins (the U5 and U2 Sm proteins, a subset of U5 snRNP-specific proteins, and the U2 snRNP-specific proteins U2A′ and U2B′′) remains unaltered upon transition from the B to the C complex. The MS-based quantification approaches classify the majority of proteins as dynamically associated specifically with the B or the C complex. In terms of experimental procedure and the methodical aspect of this work, we show that metabolically labeled spliceosomes are functionally active in terms of their assembly and splicing kinetics and can be utilized for quantitative studies. Moreover, we obtain consistent quantification results from all three methods, including the relatively straightforward and inexpensive label-free spectral count technique. PMID:24448447

  6. Marketing the Virtual Library

    Science.gov (United States)

    Fagan, Jody Condit

    2009-01-01

    Far more people are familiar with their local public or college library facility than their library's website and online resources. In fact, according to a recent survey, 96% of Americans said they had visited a library in person, but less than one-third have visited their online library. Since everyone agrees that online library resources are…

  7. Internal correction of hafnium oxide spectral interferences and mass bias in the determination of platinum in environmental samples using isotope dilution analysis.

    Science.gov (United States)

    Rodríguez-Castrillón, José Angel; Moldovan, Mariella; García Alonso, J Ignacio

    2009-05-01

    A method has been developed for the accurate determination of platinum by isotope dilution analysis, using enriched (194)Pt, in environmental samples containing comparatively high levels of hafnium without any chemical separation. The method is based on the computation of the contribution of hafnium oxide as an independent factor in the observed isotope pattern of platinum in the spiked sample. Under these conditions, the ratio of molar fractions between natural abundance and isotopically enriched platinum was independent of the amount of hafnium present in the sample. Additionally, mass bias was corrected by an internal procedure in which the regression variance was minimised. This was possible as the mass bias factor for hafnium oxide was very close to that of platinum. The final procedure required the measurement of three platinum isotope ratios (192/194, 195/194 and 196/194) to calculate the concentration of platinum in the sample. The methodology has been validated using the reference material "BCR-723 road dust" and has been applied to different environmental matrices (road dust, air particles, bulk wet deposition and epiphytic lichens) collected in the Aspe Valley (Pyrenees Mountains). A full uncertainty budget, using Kragten's spreadsheet method, showed that the total uncertainty was limited only by the uncertainty in the measured isotope ratios and not by the uncertainties of the isotopic composition of platinum and hafnium.

  8. Medium-resolution Isaac Newton Telescope library of empirical spectra - II. The stellar atmospheric parameters

    NARCIS (Netherlands)

    Cenarro, A. J.; Peletier, R. F.; Sanchez-Blazquez, P.; Selam, S. O.; Toloba, E.; Cardiel, N.; Falcon-Barroso, J.; Gorgas, J.; Jimenez-Vicente, J.; Vazdekis, A.

    2007-01-01

    We present a homogeneous set of stellar atmospheric parameters (T-eff, log g, [Fe/H]) for MILES, a new spectral stellar library covering the range lambda lambda 3525-7500 angstrom at 2.3 angstrom (FWHM) spectral resolution. The library consists of 985 stars spanning a large range in atmospheric para

  9. Chemical Evolution Library for Galaxy Formation Simulation

    Science.gov (United States)

    Saitoh, Takayuki R.

    2017-02-01

    We have developed a software library for chemical evolution simulations of galaxy formation under the simple stellar population (SSP) approximation. In this library, all of the necessary components concerning chemical evolution, such as initial mass functions, stellar lifetimes, yields from Type II and Type Ia supernovae, asymptotic giant branch stars, and neutron star mergers, are compiled from the literature. Various models are pre-implemented in this library so that users can choose their favorite combination of models. Subroutines of this library return released energy and masses of individual elements depending on a given event type. Since the redistribution manner of these quantities depends on the implementation of users’ simulation codes, this library leaves it up to the simulation code. As demonstrations, we carry out both one-zone, closed-box simulations and 3D simulations of a collapsing gas and dark matter system using this library. In these simulations, we can easily compare the impact of individual models on the chemical evolution of galaxies, just by changing the control flags and parameters of the library. Since this library only deals with the part of chemical evolution under the SSP approximation, any simulation codes that use the SSP approximation—namely, particle-base and mesh codes, as well as semianalytical models—can use it. This library is named “CELib” after the term “Chemical Evolution Library” and is made available to the community.

  10. A semi-empirical library of galaxy spectra for Gaia classification based on SDSS data and PÉGASE models

    Science.gov (United States)

    Tsalmantza, P.; Karampelas, A.; Kontizas, M.; Bailer-Jones, C. A. L.; Rocca-Volmerange, B.; Livanou, E.; Bellas-Velidis, I.; Kontizas, E.; Vallenari, A.

    2012-01-01

    Aims: This paper is the third in a series implementing a classification system for Gaia observations of unresolved galaxies. The system makes use of template galaxy spectra in order to determine spectral classes and estimate intrinsic astrophysical parameters. In previous work we used synthetic galaxy spectra produced by PÉGASE.2 code to simulate Gaia observations and to test the performance of support vector machine (SVM) classifiers and parametrizers. Here we produce a semi-empirical library of galaxy spectra by fitting SDSS spectra with the previously produced synthetic libraries. We present (1) the semi-empirical library of galaxy spectra; (2) a comparison between the observed and synthetic spectra; and (3) first results of classification and parametrization experiments with simulated Gaia spectrophotometry of this library. Methods: We use χ2-fitting to fit SDSS galaxy spectra with the synthetic library in order to construct a semi-empirical library of galaxy spectra in which (1) the real spectra are extended by the synthetic ones in order to cover the full wavelength range of Gaia; and (2) astrophysical parameters are assigned to the SDSS spectra by the best fitting synthetic spectrum. The SVM models were trained with and applied to semi-empirical spectra. Tests were performed for the classification of spectral types and the estimation of the most significant galaxy parameters (in particular redshift, mass to light ratio and star formation history). Results: We produce a semi-empirical library of 33 670 galaxy spectra covering the wavelength range 250 to 1050 nm at a sampling of 1 nm or less. Using the results of the fitting of the SDSS spectra with our synthetic library, we investigate the range of the input model parameters that produces spectra which are in good agreement with observations. In general the results are very good for the majority of the synthetic spectra of early type, spiral and irregular galaxies, while they reveal problems in the models

  11. Agricultural Libraries and Information.

    Science.gov (United States)

    Russell, Keith W., Ed.; Pisa, Maria G., Ed.

    1990-01-01

    Eleven articles address issues relating to agricultural libraries and information, including background on agricultural libraries and information, trend management, document delivery, reference services, user needs and library services, collection development, technologies for international information management, information sources,…

  12. Italian library associations

    Directory of Open Access Journals (Sweden)

    Ksenija Petaros-Kmetec

    2004-01-01

    Full Text Available In Italy, five library associations of national significance function at present. There are special associations of ecclesiastic libraries, prison libraries, architecture libraries and libraries with artistic material. The role of the general national association, covering all types of libraries including documentation centres, is played by the Italian Library Association. It strive for the development of a contemporary Italian library system comparable to international standards, monitors library legislation, promotes education for librarians and keeps the librarians and the broader public informed about the importance of libraries and librarianship for society. The activity and efforts of the association are reflected through their website offering much information and links to similar sites. ILA presents and realises its activities for both, the librarians and the public users. A great deal of actions promoting libraries and the Library Association might be interesting for Slovenia and perhaps transferred to our environment.

  13. Digital Culture and Digital Library

    Directory of Open Access Journals (Sweden)

    Yalçın Yalçınkaya

    2016-12-01

    Full Text Available In this study; digital culture and digital library which have a vital connection with each other are examined together. The content of the research consists of the interaction of culture, information, digital culture, intellectual technologies, and digital library concepts. The study is an entry work to integrity of digital culture and digital library theories and aims to expand the symmetry. The purpose of the study is to emphasize the relation between the digital culture and digital library theories acting intersection of the subjects that are examined. Also the perspective of the study is based on examining the literature and analytical evaluation in both studies (digital culture and digital library. Within this context, the methodology of the study is essentially descriptive and has an attribute for the transmission and synthesis of distributed findings produced in the field of the research. According to the findings of the study results, digital culture is an inclusive term that describes the effects of intellectual technologies in the field of information and communication. Information becomes energy and the spectrum of the information is expanding in the vertical rise through the digital culture. In this context, the digital library appears as a new living space of a new environment. In essence, the digital library is information-oriented; has intellectual technology support and digital platform; is in a digital format; combines information resources and tools in relationship/communication/cooperation by connectedness, and also it is the dynamic face of the digital culture in time and space independence. Resolved with the study is that the digital libraries are active and effective in the formation of global knowing and/or mass wisdom in the process of digital culture.

  14. Mass spectral fragmentation patterns of some new benzo[b]thiophene- and thieno[2,3-b]thiophene-2,5-dicarbonyldichlorides and -dicarbonyldianilides and anilidoquinolones.

    Science.gov (United States)

    Karminski-Zamola, G; Dogan, J; Boykin, D W; Bajić, M

    1995-01-01

    The electron impact mass spectra of some benzo[b]thiophene- and thieno[2,3-b]thiophene-2,5-dicarbonyldichlorides, 2,5-dicarbonyldianalides, 9-anilido-benzo[b]thienyl[2,3-c]quinolones and 9-anilidothieno[4,5-b']thienyl[2,3-c]quinolones are discussed. Dominant peaks in dianilides are formed by cleavage of the C-N bond on one side of the anilido group, as well as on the anilido group itself in anilidoquinolones. These ions fragment further by the cleavage of a C-C bond in dianilides and the CONRPh group is lost directly, while the quinolonic part of the molecule in quinolones fragments with low probability. Characteristic fragment ions of dicarbonyldichlorides arise by the cleavage of the C-C1 bond.

  15. Energetic processes revealed by spectrally resolved high-J CO lines in low-mass star-forming regions with Herschel-HIFI

    CERN Document Server

    Y\\ild\\iz, Umut A; Kristensen, Lars E; Visser, Ruud; Herczeg, Greg; van Kempen, Tim A; J\\orgensen, Jes K; Hogerheijde, Michiel R

    2011-01-01

    Herschel-HIFI observations of high-J lines (up to J_u=10) of 12CO, 13CO and C18O are presented toward three deeply embedded low-mass protostars in NGC1333. The observations show several energetic components including shocked and quiescent gas. Radiative transfer models are used to quantify the C18O envelope abundance which require a jump in the abundance at an evaporation temperature, T_ev ~25 K, providing new direct evidence of a CO ice evaporation zone around protostars. The abundance in the outermost part of the envelope, X_0, is within the canonical value of 2x10^-4; however the inner abundance, X_in, is found around a factor of 3-5 lower than X_0.

  16. Electronic, infrared, mass, 1H NMR spectral studies of the charge-transfer complexes of sulphonamide drugs with π-acceptors in acetonitrile

    Science.gov (United States)

    Frag, Eman Y.; Mohamed, Gehad G.

    2010-08-01

    The rapid interaction between sulphonamides (sulphamethoxazole (SMZ), sulphaguanidine (SGD), sulphaquinoxaline sodium (SQX) and sulphadimidine sodium (SDD)) as n-electron donors with the 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid, p-CLA) as π-acceptors resulted in the formation of 1:1 charge-transfer complexes as the final products with the formula [(drug) (acceptor)]. The final products of the reactions have been isolated and characterized using FT-IR, 1H NMR, mass spectroscopy and elemental analyses as well as photometric measurements and thermogravimetric analysis (TG). The stoichiometry and apparent formation constants of the complexes formed were determined by applying the conventional spectrophotometric molar ratio method.

  17. Numerical relativity and spectral methods

    Science.gov (United States)

    Grandclement, P.

    2016-12-01

    The term numerical relativity denotes the various techniques that aim at solving Einstein's equations using computers. Those computations can be divided into two families: temporal evolutions on the one hand and stationary or periodic solutions on the other one. After a brief presentation of those two classes of problems, I will introduce a numerical tool designed to solve Einstein's equations: the KADATH library. It is based on the the use of spectral methods that can reach high accuracy with moderate computational resources. I will present some applications about quasicircular orbits of black holes and boson star configurations.

  18. Comparative efficacy of plant-derived essential oils for managing ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) and their corresponding mass spectral characterization.

    Science.gov (United States)

    Ranger, Christopher M; Reding, Michael E; Oliver, Jason B; Schultz, Peter B; Moyseenko, James J; Youssef, Nadeer

    2011-10-01

    Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) pose a significant challenge to producers of ornamental nursery stock. Conventional insecticides are commonly used for management purposes, but plant-derived essential oils also may discourage ambrosia beetles from initiating attacks. To identify promising commercially available products, field-based efficacy trials were conducted in Ohio in 2009 and 2010 with the following products: Armorex (Soil Technologies), Cinnacure (Proguard, Inc.), EcoTrol (EcoSMART Technologies, Inc.), and Veggie Pharm (Pharm Solutions, Inc.). Potted Magnolia virginiana L. were first injected with 75 ml of 5% ethanol to ensure ambrosia beetle pressure on experimental trees. Mixtures of each product (10% in water) and a water control were applied until runoff and attacks occurring under field conditions were quantified at 1, 4, 7, and 14 d after treatment (DAT). Ambrosia beetle attacks generally increased over time but at differing rates depending on the particular treatment. In 2009, Armorex and Veggie Pharm were associated with the lowest cumulative attacks 14 DAT. In 2010, Armorex and Cinnacure were associated with the fewest attacks 14 DAT. Solid phase microextraction-gas chromatography-mass spectrometry was used to characterize the volatile compounds associated with each product. Allyl isothiocyanate, a compound with known repellent and insecticidal properties, was unique and predominant in Armorex. These experiments identified commercially available botanicals containing plant essential oils with activity against ambrosia beetles, along with demonstrating the usefulness of ethanol-injection to ensure ambrosia beetle pressure under field conditions. Characterizing the constituents of efficacious botanically based products could also lead to the development of improved botanical insecticides.

  19. Differential binding of ppGpp and pppGpp to E. coli RNA polymerase: photo-labeling and mass spectral studies.

    Science.gov (United States)

    Syal, Kirtimaan; Chatterji, Dipankar

    2015-12-01

    (p)ppGpp, a secondary messenger, is induced under stress and shows pleiotropic response. It binds to RNA polymerase and regulates transcription in Escherichia coli. More than 25 years have passed since the first discovery was made on the direct interaction of ppGpp with E. coli RNA polymerase. Several lines of evidence suggest different modes of ppGpp binding to the enzyme. Earlier cross-linking experiments suggested that the β-subunit of RNA polymerase is the preferred site for ppGpp, whereas recent crystallographic studies pinpoint the interface of β'/ω-subunits as the site of action. With an aim to validate the binding domain and to follow whether tetra- and pentaphosphate guanosines have different location on RNA polymerase, this work was initiated. RNA polymerase was photo-labeled with 8-azido-ppGpp/8-azido-pppGpp, and the product was digested with trypsin and subjected to mass spectrometry analysis. We observed three new peptides in the trypsin digest of the RNA polymerase labeled with 8-azido-ppGpp, of which two peptides correspond to the same pocket on β'-subunit as predicted by X-ray structural analysis, whereas the third peptide was mapped on the β-subunit. In the case of 8-azido-pppGpp-labeled RNA polymerase, we have found only one cross-linked peptide from the β'-subunit. However, we were unable to identify any binding site of pppGpp on the β-subunit. Interestingly, we observed that pppGpp at high concentration competes out ppGpp bound to RNA polymerase more efficiently, whereas ppGpp cannot titrate out pppGpp. The competition between tetraphosphate guanosine and pentaphosphate guanosine for E. coli RNA polymerase was followed by gel-based assay as well as by a new method known as DRaCALA assay.

  20. Enhanced peptide quantification using spectral count clustering and cluster abundance

    Directory of Open Access Journals (Sweden)

    Lee Seungmook

    2011-10-01

    Full Text Available Abstract Background Quantification of protein expression by means of mass spectrometry (MS has been introduced in various proteomics studies. In particular, two label-free quantification methods, such as spectral counting and spectra feature analysis have been extensively investigated in a wide variety of proteomic studies. The cornerstone of both methods is peptide identification based on a proteomic database search and subsequent estimation of peptide retention time. However, they often suffer from restrictive database search and inaccurate estimation of the liquid chromatography (LC retention time. Furthermore, conventional peptide identification methods based on the spectral library search algorithms such as SEQUEST or SpectraST have been found to provide neither the best match nor high-scored matches. Lastly, these methods are limited in the sense that target peptides cannot be identified unless they have been previously generated and stored into the database or spectral libraries. To overcome these limitations, we propose a novel method, namely Quantification method based on Finding the Identical Spectral set for a Homogenous peptide (Q-FISH to estimate the peptide's abundance from its tandem mass spectrometry (MS/MS spectra through the direct comparison of experimental spectra. Intuitively, our Q-FISH method compares all possible pairs of experimental spectra in order to identify both known and novel proteins, significantly enhancing identification accuracy by grouping replicated spectra from the same peptide targets. Results We applied Q-FISH to Nano-LC-MS/MS data obtained from human hepatocellular carcinoma (HCC and normal liver tissue samples to identify differentially expressed peptides between the normal and disease samples. For a total of 44,318 spectra obtained through MS/MS analysis, Q-FISH yielded 14,747 clusters. Among these, 5,777 clusters were identified only in the HCC sample, 6,648 clusters only in the normal tissue sample

  1. A spectral invariant representation of spectral reflectance

    Science.gov (United States)

    Ibrahim, Abdelhameed; Tominaga, Shoji; Horiuchi, Takahiko

    2011-03-01

    Spectral image acquisition as well as color image is affected by several illumination factors such as shading, gloss, and specular highlight. Spectral invariant representations for these factors were proposed for the standard dichromatic reflection model of inhomogeneous dielectric materials. However, these representations are inadequate for other characteristic materials like metal. This paper proposes a more general spectral invariant representation for obtaining reliable spectral reflectance images. Our invariant representation is derived from the standard dichromatic reflection model for dielectric materials and the extended dichromatic reflection model for metals. We proof that the invariant formulas for spectral images of natural objects preserve spectral information and are invariant to highlights, shading, surface geometry, and illumination intensity. It is proved that the conventional spectral invariant technique can be applied to metals in addition to dielectric objects. Experimental results show that the proposed spectral invariant representation is effective for image segmentation.

  2. Realizing the Hybrid Library.

    Science.gov (United States)

    Pinfield, Stephen; Eaton, Jonathan; Edwards, Catherine; Russell, Rosemary; Wissenburg, Astrid; Wynne, Peter

    1998-01-01

    Outlines five projects currently funded by the United Kingdom's Electronic Libraries Program (eLib): HyLiFe (Hybrid Library of the Future), MALIBU (MAnaging the hybrid Library for the Benefit of Users), HeadLine (Hybrid Electronic Access and Delivery in the Library Networked Environment), ATHENS (authentication scheme), and BUILDER (Birmingham…

  3. Special Library Services.

    Science.gov (United States)

    Ensley, Robert F., Ed.

    1975-01-01

    The September 1975 issue of Illinois Libraries focuses on the needs of the developmentally disabled, physically handicapped, and emotionally disturbed. Articles on library services to the blind and physically handicapped cover standards, services of local public libraries, Library of Congress programs, braille books and sound recordings,…

  4. The library marketing toolkit

    CERN Document Server

    Potter, Ned

    2012-01-01

    A guide that offers coverage of various elements of library marketing and branding for different sectors including archives and academic, public and special libraries. It is suitable for those who are involved in promoting their library or information service, whether at an academic, public or special library or in archives or records management.

  5. Libraries and Learning

    Science.gov (United States)

    Rainie, Lee

    2016-01-01

    The majority of Americans think local libraries serve the educational needs of their communities and families pretty well and library users often outpace others in learning activities. But many do not know about key education services libraries provide. This report provides statistics on library usage and presents key education services provided…

  6. Growing Competition for Libraries.

    Science.gov (United States)

    Gibbons, Susan

    2001-01-01

    Describes the Questia subscription-based online academic digital books library. Highlights include weaknesses of the collection; what college students want from a library; importance of marketing; competition for traditional academic libraries that may help improve library services; and the ability of Questia to overcome barriers and…

  7. The "Integrated Library System."

    Science.gov (United States)

    Dowlin, Kenneth E.

    1985-01-01

    Reviews internal and external dimensions of library environment that must be taken into account by library managers when choosing an integrated library system. The selection, acquisition, and implementation stages of Maggie III--a computerized library system sensitive to the internal and external organizational environment--are described. (MBR)

  8. Teleporting the library?

    DEFF Research Database (Denmark)

    Heilesen, Simon

    2009-01-01

    In 2007, six Danish public libraries established a virtual library, Info Island DK, in Second Life. This article discusses the library project in terms of design. The design processes include the planning and implementation of the virtual library structure and its equipment, as well as the organi...

  9. Training of Library Assistants in Academic Library

    Directory of Open Access Journals (Sweden)

    Itunu A. Bamidele

    2013-09-01

    Full Text Available The purpose of this research is to identify the need to train and retrain library assistants in academic libraries. The researchers however used Babcock University Library to ascertain the impacts of training of library assistants. A descriptive design was adopted for this study. A total enumeration sampling method was used. The instrument used for data collection was a structured questionnaire. The population was made up of 30 respondents who were library assistants at the Babcock University Library, Nigeria. A total number of 30 questionnaires were administered. All the questionnaires were retrieved and were found useful giving a return rate of 100% used for this study. The result shows that library assistants were not given training in the area of system management and web searching. In addition, 27 (90% of the respondents agreed that training will enhance their job performance while 30 (100% of the respondents agreed that training will improve their skills to support library users in searching for information electronically. Based on the findings the researchers recommend that library assistants should be trained on electronic information technology usage as this will impact the overall service delivery in meeting the goals of the academic library.

  10. Spectral Decomposition Algorithm (SDA)

    Data.gov (United States)

    National Aeronautics and Space Administration — Spectral Decomposition Algorithm (SDA) is an unsupervised feature extraction technique similar to PCA that was developed to better distinguish spectral features in...

  11. America's Star Libraries, 2010: Top-Rated Libraries

    Science.gov (United States)

    Lyons, Ray; Lance, Keith Curry

    2010-01-01

    The "LJ" Index of Public Library Service 2010, "Library Journal"'s national rating of public libraries, identifies 258 "star" libraries. Created by Ray Lyons and Keith Curry Lance, and based on 2008 data from the IMLS, it rates 7,407 public libraries. The top libraries in each group get five, four, or three stars. All included libraries, stars or…

  12. America's Star Libraries, 2010: Top-Rated Libraries

    Science.gov (United States)

    Lyons, Ray; Lance, Keith Curry

    2010-01-01

    The "LJ" Index of Public Library Service 2010, "Library Journal"'s national rating of public libraries, identifies 258 "star" libraries. Created by Ray Lyons and Keith Curry Lance, and based on 2008 data from the IMLS, it rates 7,407 public libraries. The top libraries in each group get five, four, or three stars. All included libraries, stars or…

  13. 高面质比低轨空间碎片表面材料光谱特性研究%Surface Material Spectral Characterization of High Area-to-mass Ratio LEO Space Debris

    Institute of Scientific and Technical Information of China (English)

    金小龙; 唐轶峻; 隋成华

    2013-01-01

    High area-to-mass ratio space debris currently poses an increasing hazard to active satellites in orbit and manned space activities. Due to the difficulties in recognition and cataloging of high area-to-mass space debris, a method based on spectroscopic observations is proposed. This method corrects atmospheric extinction and the impact of telescope optical system on the basis of image preprocessing, extracts space debris reflectance spectroscopy, then compares with the spectral curves of sample materials and recognizes surface materials of high area-to-mass ratio space debris. Results of spectroscopic observations show that it will be fairly accurate if high area-to-mass ratio space debris is composed of a single material, such as aluminum and white paint, and the correlation coefficients of aluminum and white paint are approximately 0.9.%当前高面质比空间碎片对在轨航天器及载人航天活动的威胁与日俱增,针对高面质比空间碎片轨道漂移造成编目识别困难,提出利用碎片表面材料的光谱特性识别高面质比空间碎片。该方法对空间碎片图像预处理,修正其大气消光和望远镜光学系统的影响,抽取碎片光谱曲线,将实测光谱曲线与样本材料进行比对,分析两者光谱曲线特性,识别高面质比空间碎片表面材料。低色散光谱观测数据表明:该方法对于铝、白漆单一表面材料为主的卫星和火箭箭体等高面质比空间碎片具有较高的准确性,其相关系数大于0.9。

  14. SPAM- SPECTRAL ANALYSIS MANAGER (UNIX VERSION)

    Science.gov (United States)

    Solomon, J. E.

    1994-01-01

    The Spectral Analysis Manager (SPAM) was developed to allow easy qualitative analysis of multi-dimensional imaging spectrometer data. Imaging spectrometers provide sufficient spectral sampling to define unique spectral signatures on a per pixel basis. Thus direct material identification becomes possible for geologic studies. SPAM provides a variety of capabilities for carrying out interactive analysis of the massive and complex datasets associated with multispectral remote sensing observations. In addition to normal image processing functions, SPAM provides multiple levels of on-line help, a flexible command interpretation, graceful error recovery, and a program structure which can be implemented in a variety of environments. SPAM was designed to be visually oriented and user friendly with the liberal employment of graphics for rapid and efficient exploratory analysis of imaging spectrometry data. SPAM provides functions to enable arithmetic manipulations of the data, such as normalization, linear mixing, band ratio discrimination, and low-pass filtering. SPAM can be used to examine the spectra of an individual pixel or the average spectra over a number of pixels. SPAM also supports image segmentation, fast spectral signature matching, spectral library usage, mixture analysis, and feature extraction. High speed spectral signature matching is performed by using a binary spectral encoding algorithm to separate and identify mineral components present in the scene. The same binary encoding allows automatic spectral clustering. Spectral data may be entered from a digitizing tablet, stored in a user library, compared to the master library containing mineral standards, and then displayed as a timesequence spectral movie. The output plots, histograms, and stretched histograms produced by SPAM can be sent to a lineprinter, stored as separate RGB disk files, or sent to a Quick Color Recorder. SPAM is written in C for interactive execution and is available for two different

  15. Toy Library and International Toy Library Association

    OpenAIRE

    Kamaraj, Işık

    2013-01-01

    Toy libraries are resource centers that provides assistance to young children and theirfamilies, gives consultancy service and information about plays, offers play materials andeducational activities and supplies appropriate materials and toys for child development aswell as contributing the development of children. Toy libraries are in commission all over theworld since 1935. The first toy library is opened in America, then in Sweden, England,Canada and Australia respectively. Today, there a...

  16. Libraries and Accessibility: Istanbul Public Libraries Case

    Directory of Open Access Journals (Sweden)

    Gül Yücel

    2016-12-01

    Full Text Available In the study; the assessment of accessibility has been conducted in Istanbul public libraries within the scope of public area. Public libraries commonly serve with its user of more than 20 million in total, spread to the general of Turkey, having more than one thousand branches in the centrums and having more than one million registered members. The building principles and standards covering the subjects such as the selection of place, historical and architectural specification of the region, distance to the centre of population and design in a way that the disabled people could benefit from the library services fully have been determined with regulations in the construction of new libraries. There are works for the existent libraries such as access for the disabled, fire safety precautions etc. within the scope of the related standards. Easy access by everyone is prioritized in the public libraries having a significant role in life-long learning. The purpose of the study is to develop solution suggestions for the accessibility problems in the public libraries. The study based on the eye inspection and assessments carried out within the scope of accessibility in the public libraries subsidiary to Istanbul Culture and Tourism Provincial Directorate Library and Publications Department within the provincial borders of Istanbul. The arrangements such as reading halls, study areas, book shelves etc. have been examined within the frame of accessible building standards. Building entrances, ramps and staircases, horizontal and vertical circulation of building etc. have been taken into consideration within the scope of accessible building standards. The subjects such as the reading and studying areas and book shelf arrangements for the library have been assessed within the scope of specific buildings. There are a total of 34 public libraries subsidiary to Istanbul Culture and Tourism Provincial Directorate on condition that 20 ea. of them are in the

  17. Improvement of AMGA Python Client Library for Belle II Experiment

    Science.gov (United States)

    Kwak, Jae-Hyuck; Park, Geunchul; Huh, Taesang; Hwang, Soonwook

    2015-12-01

    This paper describes the recent improvement of the AMGA (ARDA Metadata Grid Application) python client library for the Belle II Experiment. We were drawn to the action items related to library improvement after in-depth discussions with the developer of the Belle II distributed computing system. The improvement includes client-side metadata federation support in python, DIRAC SSL library support as well as API refinement for synchronous operation. Some of the improvements have already been applied to the AMGA python client library as bundled with the Belle II distributed computing software. The recent mass Monte- Carlo (MC) production campaign shows that the AMGA python client library is reliably stable.

  18. P-MaNGA: Full spectral fitting and stellar population maps from prototype observations

    CERN Document Server

    Wilkinson, David M; Thomas, Daniel; Coccato, Lodovico; Tojeiro, Rita; Cappellari, Michele; Belfiore, Francesco; Bershady, Matthew; Blanton, Mike; Bundy, Kevin; Cales, Sabrina; Cherinka, Brian; Drory, Niv; Emsellem, Eric; Fu, Hai; Law, David; Li, Cheng; Maiolino, Roberto; Masters, Karen; Tremonti, Christy; Wake, David; Wang, Enci; Weijmans, Anne-Marie; Xiao, Ting; Yan, Renbin; Zhang, Kai; Bizyaev, Dmitry; Brinkmann, Jonathan; Kinemuchi, Karen; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Daniel; Pan, Kaike; Simmons, Audrey

    2015-01-01

    MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) is a 6-year SDSS-IV survey that will obtain resolved spectroscopy from 3600 $\\AA$ to 10300 $\\AA$ for a representative sample of over 10,000 nearby galaxies. In this paper, we derive spatially resolved stellar population properties and radial gradients by performing full spectral fitting of observed galaxy spectra from P-MaNGA, a prototype of the MaNGA instrument. These data include spectra for eighteen galaxies, covering a large range of morphological type. We derive age, metallicity, dust and stellar mass maps, and their radial gradients, using high spectral-resolution stellar population models, and assess the impact of varying the stellar library input to the models. We introduce a method to determine dust extinction which is able to give smooth stellar mass maps even in cases of high and spatially non-uniform dust attenuation. With the spectral fitting we produce detailed maps of stellar population properties which allow us to identify galactic fe...

  19. Quantum Spectral Symmetries

    Science.gov (United States)

    Hamhalter, Jan; Turilova, Ekaterina

    2017-02-01

    Quantum symmetries of spectral lattices are studied. Basic properties of spectral order on A W ∗-algebras are summarized. Connection between projection and spectral automorphisms is clarified by showing that, under mild conditions, any spectral automorphism is a composition of function calculus and Jordan ∗-automorphism. Complete description of quantum spectral symmetries on Type I and Type II A W ∗-factors are completely described.

  20. Peakfitter — an integrated Excel-based Visual Basic program for processing multiple skewed and shifting Gaussian-like spectral peaks simultaneously: application to radio frequency glow discharge ion trap mass spectrometry

    Science.gov (United States)

    Eanes, Ritchie C.; Marcus, R. Kenneth

    2000-04-01

    This article is an electronic publication in Spectrochimica Acta Electronica (SAE), a section of Spectrochimica Acta Part B (SAB). The hardcopy text is accompanied by an electronic archive, stored on the SAE homepage at (http://www.elsevier.nl/locate/sabe). The archive contains program and data files. The main article discusses the scientific spectroscopic and instrumental aspects of the subject and explains the purpose of the program and data files. The work deals with a Microsoft Excel Visual Basic program, Peakfitter, which can process multiple Gaussian-shaped spectral peaks quickly and easily. The program employs Microsoft Excel Solver to process any Gaussian-like spectra that can be opened in Microsoft Excel 97. Up to three peaks in one to 225 spectra, each containing up to 2000 data points can be processed per data file to give background corrected peak areas for both raw data and its associated fit data as calculated by the trapezoidal method or by simple successive addition of channel intensities across each peak. Concurrently output also includes fit peak heights for Gaussian-shaped spectral peaks. Use of other statistical distributions such as the Lorentzian model requires only slight modification to a template file. Hence, Peakfitter was actually written as two application programs, 'Gaussfitter' and 'Lorenfitter' to accommodate spectra of Gaussian or Lorentzian character, respectively. Written initially to process data from a radio frequency glow discharge ion trap mass spectrometer (rf-GD/ITMS), the program is useful for processing sequentially acquired spectra, which have a limited number of data points across each peak. The user may examine and manipulate program variables in cases where the raw data is skewed with respect to the fit data. An assessment of Peakfitter is given using rf-GD/ITMS elemental analysis and ion-molecule reaction data. Peakfitter's (i.e. 'Gaussfitter's) utility in processing rf-GD/ITMS spectra is characterized by a slight

  1. Library Advocacy Now! Library Advocate's Handbook. [Videotape.

    Science.gov (United States)

    American Library Association Video/Library Video Network, Towson, MD.

    Libraries are one of the world's greatest assets. Changes in the political, social, and economic climate in the U.S. mean that people cannot take public access to information for granted. Intense competition for public, private, and institutional dollars makes it more crucial than ever that policymakers understand that libraries--public, school,…

  2. Libraries - LIBRARIES_ISL_IN: Libraries in Indiana (Indiana State Library, Point Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — LIBRARIES_ISL_IN is a point shapefile showing the locations of 528 libraries included in Microsoft Excel spreadsheets that are downloadable from the Web page named...

  3. Libraries serving dialogue

    CERN Document Server

    Dupont, Odile

    2014-01-01

    This book based on experiences of libraries serving interreligious dialogue, presents themes like library tools serving dialogue between cultures, collections dialoguing, children and young adults dialoguing beyond borders, story telling as dialog, librarians serving interreligious dialogue.

  4. Integrated library systems.

    Science.gov (United States)

    Goldstein, C M

    1983-07-01

    The development of integrated library systems is discussed. The four major discussion points are (1) initial efforts; (2) network resources; (3) minicomputer-based systems; and (4) beyond library automation. Four existing systems are cited as examples of current systems.

  5. Reutilizing Existing Library Space.

    Science.gov (United States)

    Davis, Marlys Cresap

    1987-01-01

    This discussion of the reutilization of existing library space reviews the decision process and considerations for implementation. Two case studies of small public libraries which reassigned space to better use are provided, including floor plans. (1 reference) (MES)

  6. New strategies to screen for endocrine-disrupting chemicals in the Portuguese marine environment utilizing large volume injection-capillary gas chromatography-mass spectrometry combined with retention time locking libraries (LVI-GC-MS-RTL).

    Science.gov (United States)

    Almeida, C; Serôdio, P; Florêncio, M H; Nogueira, J M F

    2007-04-01

    A new analytical strategy to screen for endocrine-disrupting chemicals (EDCs) in environmental matrices is presented. The strategy uses solid-phase extraction followed by large volume injection and capillary gas chromatography coupled to mass spectrometry combined with retention time locking libraries (SPE-LVI-GC-MS-RTL). Characterization of the proposed methodology (SPE-LVI-GC-MS) for selected classes of EDCs enabled high reproducibility and robustness at the ultratrace level. The RTL databases used allowed hundreds of non-target semivolatiles (i.e., pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls and other classes of suspected EDCs from a great number of unknown environmental matrices) to be simultaneously screened for in an easy, fast and remarkable manner. The application of the proposed methodology to real environmental samples demonstrated its remarkable selectivity and sensitivity at the ultratrace level. Screening assessments performed on water and sediment matrices from eight Portuguese estuaries and coastal waters identified EDC "hotspots." These EDCs mainly come from agricultural and a wide variety of industrial sources, and include pesticides and pesticide metabolites, phenolic derivatives and polycyclic aromatic hydrocarbons, which are included in the lists of priority substances published by international environmental agencies. The estuaries that contained relatively high levels of pesticides were Guadiana, Sado and Mondego, while Minho, Douro and Formosa showed enhanced levels of phenolic derivatives. Dibutyltin and tributyltin, selected as target compounds to be monitored by SPE-LVI-GC-MS in the selected ion monitoring mode, were shown to be widespread contaminants at trace levels in almost all of the sediment matrices assessed. The reliability of the proposed methodology undoubtedly makes it a valuable tool that could replace other analytical strategies currently used to screen for EDCs present in the environment at

  7. Library planning in Germany

    Directory of Open Access Journals (Sweden)

    Friedrich Geisselmann

    2003-12-01

    Full Text Available The position and the efficiency of German libraries are rather ambivalent. On the one hand the infrastructure is quite well developed: 2000 public library systems with full time personnel, 275 million books issued, 75 million Euro for acquisitions; 280 scientific general libraries, 60 million books issued, 1300 million Euro for acquisitions. Nevertheless there are a lot of problems, which arise from the administrative structure and the political position of libraries.

  8. The Spectral Shift Function and Spectral Flow

    Science.gov (United States)

    Azamov, N. A.; Carey, A. L.; Sukochev, F. A.

    2007-11-01

    At the 1974 International Congress, I. M. Singer proposed that eta invariants and hence spectral flow should be thought of as the integral of a one form. In the intervening years this idea has lead to many interesting developments in the study of both eta invariants and spectral flow. Using ideas of [24] Singer’s proposal was brought to an advanced level in [16] where a very general formula for spectral flow as the integral of a one form was produced in the framework of noncommutative geometry. This formula can be used for computing spectral flow in a general semifinite von Neumann algebra as described and reviewed in [5]. In the present paper we take the analytic approach to spectral flow much further by giving a large family of formulae for spectral flow between a pair of unbounded self-adjoint operators D and D + V with D having compact resolvent belonging to a general semifinite von Neumann algebra {mathcal{N}} and the perturbation V in {mathcal{N}} . In noncommutative geometry terms we remove summability hypotheses. This level of generality is made possible by introducing a new idea from [3]. There it was observed that M. G. Krein’s spectral shift function (in certain restricted cases with V trace class) computes spectral flow. The present paper extends Krein’s theory to the setting of semifinite spectral triples where D has compact resolvent belonging to {mathcal{N}} and V is any bounded self-adjoint operator in {mathcal{N}} . We give a definition of the spectral shift function under these hypotheses and show that it computes spectral flow. This is made possible by the understanding discovered in the present paper of the interplay between spectral shift function theory and the analytic theory of spectral flow. It is this interplay that enables us to take Singer’s idea much further to create a large class of one forms whose integrals calculate spectral flow. These advances depend critically on a new approach to the calculus of functions of non

  9. $\\rho$ - meson spectral function in hot nuclear matter

    CERN Document Server

    Bhageerathi, P C Raje

    2010-01-01

    We study the $\\rho$-meson spectral function in hot nuclear matter by taking into account the isospin-symmetric pion and the nucleon loops within the quantum hadrodynamics (QHD) model as well as using an effective chiral SU(3) model. The spectral function of the $\\rho$ meson is studied in the mean field approximation (MFA) as well as in the relativistic Hartree (RHA) approximation. The inclusion of the nucleon loop considerably changes the $\\rho$-meson spectral function. Due to a larger mass drop of $ \\rho $ meson in the RHA, it is seen that the spectral function shifts towards the low invariant mass region, whereas in the MFA the spectral function is seen to be slightly shifted towards the high mass region. Moreover, while the spectral function is observed to be sharper with the nucleon-antinucleon polarization in RHA, the spectral function is seen to be broader in the MFA.

  10. Learning Boost C++ libraries

    CERN Document Server

    Mukherjee, Arindam

    2015-01-01

    If you are a C++ programmer who has never used Boost libraries before, this book will get you up-to-speed with using them. Whether you are developing new C++ software or maintaining existing code written using Boost libraries, this hands-on introduction will help you decide on the right library and techniques to solve your practical programming problems.

  11. Library Skills Workbook.

    Science.gov (United States)

    Miller, Constance; And Others

    This self-paced library skills workbook provides incoming students with an introduction to the physical arrangement and use of the university libraries. Divided into two sections, the first contains explanations of the catalogs, classification system, and various library resources. The second consists of practical exercises keyed to the…

  12. Biology Library Workbook.

    Science.gov (United States)

    Miller, Constance; And Others

    A library skills workbook provides college biology students with an introduction to biological library resources. Divided into two sections, the first contains explanations of the various steps in the library research process. The second consists of exercises keyed to the explanatory chapters of the first section. (RAA)

  13. A Truly Bookless Library

    Science.gov (United States)

    Kolowich, Steve

    2011-01-01

    The difference between the University of Texas at San Antonio's Applied Engineering and Technology Library and other science-focused libraries is not that its on-site collection is also available electronically. It is that its on-site collection is only available electronically. The idea of libraries with no bound books has been a recurring theme…

  14. Changing State Digital Libraries

    Science.gov (United States)

    Pappas, Marjorie L.

    2006-01-01

    Research has shown that state virtual or digital libraries are evolving into websites that are loaded with free resources, subscription databases, and instructional tools. In this article, the author explores these evolving libraries based on the following questions: (1) How user-friendly are the state digital libraries?; (2) How do state digital…

  15. Technostress and Library Values.

    Science.gov (United States)

    Gorman, Michael

    2001-01-01

    Discusses information overload and society's and libraries' responses to technology. Considers eight values that libraries should focus on and how they relate to technology in libraries: democracy, stewardship, service, intellectual freedom, privacy, rationalism, equity of access, and building harmony and balance. (LRW)

  16. Changing State Digital Libraries

    Science.gov (United States)

    Pappas, Marjorie L.

    2006-01-01

    Research has shown that state virtual or digital libraries are evolving into websites that are loaded with free resources, subscription databases, and instructional tools. In this article, the author explores these evolving libraries based on the following questions: (1) How user-friendly are the state digital libraries?; (2) How do state digital…

  17. Body Basics Library

    Science.gov (United States)

    ... Sport for You Shyness About the Body Basics Library KidsHealth > For Teens > About the Body Basics Library Print A A A Did you ever wonder ... system, part, and process works. Use this medical library to find out about basic human anatomy, how ...

  18. School Libraries and Innovation

    Science.gov (United States)

    McGrath, Kevin G.

    2015-01-01

    School library programs have measured success by improved test scores. But how do next-generation school libraries demonstrate success as they strive to be centers of innovation and creativity? These libraries offer solutions for school leaders who struggle to restructure existing systems built around traditional silos of learning (subjects and…

  19. Body Basics Library

    Science.gov (United States)

    ... of Healthy Breakfasts Shyness About the Body Basics Library KidsHealth > For Teens > About the Body Basics Library A A A Did you ever wonder what ... system, part, and process works. Use this medical library to find out about basic human anatomy, how ...

  20. Public Library Finance.

    Science.gov (United States)

    Mason, Marilyn Gell

    This study reviews trends in public library finance; examines recent political, economic, and technological changes; and assesses the impact of these changes on public library services. A history of the public library in America is presented, as well as an analysis of the principles of economics and public finance which reveals that current…

  1. The Electronic, Eclectic Library.

    Science.gov (United States)

    Dowlin, Kenneth E.

    1980-01-01

    Utilization of telecommunications and computer technology to increase access to information is identified as a primary goal for public libraries. To further service in the future, libraries should consider database services, online access to library resources, online community conferencing, community databases, network resource sharing,…

  2. Merchandising Your Library.

    Science.gov (United States)

    Sivulich, Kenneth G.

    1989-01-01

    Discusses library circulation figures as a reflection of the success of library services and describes merchandising techniques that have produced a 137 percent circulation increase at Queens Borough Public Library over the past seven years. Merchandising techniques such as minibranches, displays, signage, dumps, and modified shelving are…

  3. Marketing Academic Libraries

    Science.gov (United States)

    Mallon, Melissa, Ed.

    2013-01-01

    Ask any academic librarian if marketing their library and its services is an important task, and the answer will most likely be a resounding "yes!" Particularly in economically troubled times, librarians are increasingly called upon to promote their services and defend their library's worth. Since few academic libraries have in-house marketing…

  4. Merchandising Your Library.

    Science.gov (United States)

    Sivulich, Kenneth G.

    1989-01-01

    Discusses library circulation figures as a reflection of the success of library services and describes merchandising techniques that have produced a 137 percent circulation increase at Queens Borough Public Library over the past seven years. Merchandising techniques such as minibranches, displays, signage, dumps, and modified shelving are…

  5. Marketing Academic Libraries

    Science.gov (United States)

    Mallon, Melissa, Ed.

    2013-01-01

    Ask any academic librarian if marketing their library and its services is an important task, and the answer will most likely be a resounding "yes!" Particularly in economically troubled times, librarians are increasingly called upon to promote their services and defend their library's worth. Since few academic libraries have in-house marketing…

  6. School Libraries and Innovation

    Science.gov (United States)

    McGrath, Kevin G.

    2015-01-01

    School library programs have measured success by improved test scores. But how do next-generation school libraries demonstrate success as they strive to be centers of innovation and creativity? These libraries offer solutions for school leaders who struggle to restructure existing systems built around traditional silos of learning (subjects and…

  7. FY 2009 Public Libraries Survey

    Data.gov (United States)

    Institute of Museum and Library Services — Dig into FY 2009 data on public library systems (referred to as administrative entities in the Public Libraries Survey) and main libraries, branches, and bookmobiles...

  8. FY 2011 Public Libraries Survey

    Data.gov (United States)

    Institute of Museum and Library Services — Dig into FY 2011 data on public library systems (referred to as administrative entities in the Public Libraries Survey) and main libraries, branches, and bookmobiles...

  9. FY 2010 Public Libraries Survey

    Data.gov (United States)

    Institute of Museum and Library Services — Dig into FY 2010 data on public library systems (referred to as administrative entities in the Public Libraries Survey) and main libraries, branches, and bookmobiles...

  10. FY 2008 Public Libraries Survey

    Data.gov (United States)

    Institute of Museum and Library Services — Dig into FY 2008 data on public library systems (referred to as administrative entities in the Public Libraries Survey) and main libraries, branches, and bookmobiles...

  11. Multi-material decomposition of spectral CT images

    Science.gov (United States)

    Mendonça, Paulo R. S.; Bhotika, Rahul; Maddah, Mahnaz; Thomsen, Brian; Dutta, Sandeep; Licato, Paul E.; Joshi, Mukta C.

    2010-04-01

    Spectral Computed Tomography (Spectral CT), and in particular fast kVp switching dual-energy computed tomography, is an imaging modality that extends the capabilities of conventional computed tomography (CT). Spectral CT enables the estimation of the full linear attenuation curve of the imaged subject at each voxel in the CT volume, instead of a scalar image in Hounsfield units. Because the space of linear attenuation curves in the energy ranges of medical applications can be accurately described through a two-dimensional manifold, this decomposition procedure would be, in principle, limited to two materials. This paper describes an algorithm that overcomes this limitation, allowing for the estimation of N-tuples of material-decomposed images. The algorithm works by assuming that the mixing of substances and tissue types in the human body has the physicochemical properties of an ideal solution, which yields a model for the density of the imaged material mix. Under this model the mass attenuation curve of each voxel in the image can be estimated, immediately resulting in a material-decomposed image triplet. Decomposition into an arbitrary number of pre-selected materials can be achieved by automatically selecting adequate triplets from an application-specific material library. The decomposition is expressed in terms of the volume fractions of each constituent material in the mix; this provides for a straightforward, physically meaningful interpretation of the data. One important application of this technique is in the digital removal of contrast agent from a dual-energy exam, producing a virtual nonenhanced image, as well as in the quantification of the concentration of contrast observed in a targeted region, thus providing an accurate measure of tissue perfusion.

  12. German Librarianship and Munich Libraries

    Directory of Open Access Journals (Sweden)

    Osman Ümit Özen

    1994-06-01

    Full Text Available There are 27 municipal libraries including the Central Public Library in Munich. The other important libraries in the city are Bayern State National Library, Maximillian University Library, a technical highschool library and the "Deutsches Musuem" Library. All these libraries are financed locally. The author introduces these libraries briefly and compares German libraries with Turkish libraries. He concludes that although theoretically there are not distinctive differences, in practice, buildings and their layout are better in Germany where more variety of services are offered. In Turkey standardization has not been realized yet. Turkey needs to computerize and network to improve the services offered in an efficient way.

  13. The power of low-resolution spectroscopy: On the spectral classification of planet candidates in the ground-based CoRoT follow-up

    CERN Document Server

    Eiff, M Ammler-von; Guenther, E W; Stecklum, B; Cabrera, J

    2015-01-01

    Planetary transits detected by the CoRoT mission can be mimicked by a low-mass star in orbit around a giant star. Spectral classification helps to identify the giant stars and also early-type stars which are often excluded from further follow-up. We study the potential and the limitations of low-resolution spectroscopy to improve the photometric spectral types of CoRoT candidates. In particular, we want to study the influence of the signal-to-noise ratio (SNR) of the target spectrum in a quantitative way. We built an own template library and investigate whether a template library from the literature is able to reproduce the classifications. Including previous photometric estimates, we show how the additional spectroscopic information improves the constraints on spectral type. Low-resolution spectroscopy ($R\\approx$1000) of 42 CoRoT targets covering a wide range in SNR (1-437) and of 149 templates was obtained in 2012-2013 with the Nasmyth spectrograph at the Tautenburg 2m telescope. Spectral types have been d...

  14. Libraries in Society

    DEFF Research Database (Denmark)

    Kristiansson, Michael; Skouvig, Laura

    understood in a library setting. Historically, openness in form of the open shelves played a crucial role in developing the modern public library. The paper examines this openness-centred library policy as adopted by Danish public libraries in the beginning of the 20th century by applying the theories...... by Michel Foucault on discourse and power to the introduction of open shelves. Furthermore, the paper discusses current challenges facing the modern public library in coping with openness issues that follow from changes in society and advances in technology. These influences and developments are not least...

  15. Library/vendor relationships

    CERN Document Server

    Brooks, Sam

    2014-01-01

    A view of the mutual dependence between libraries and vendorsAs technology advances, libraries are forced to reach beyond their own resources to find effective ways to maintain accuracy and superior service levels. Vendors provide databases and integrated library systems that perform those functions for profit. Library/Vendor Relationships examines the increasing cooperation in which libraries find they must participate in, and vice versa, with the vendors that provide system infrastructure and software. Expert contributors provide insights from all sides of this unique collaboration, offering

  16. Library system of Italy

    Directory of Open Access Journals (Sweden)

    Nataša Gerbec

    2003-01-01

    Full Text Available In the European extent, Italy is the cradle of libraries and library sciences. In the past, Italian national public libraries played an important role through their vast book treasury. But only during the last thirty years have public libraries been developed following the Anglo-American public library model. Italy does not have any uniform or general legislation concerning libraries. On the state level, this area is regulated by some separate acts, while on the regional level there is a collection of various acts and regulations. Libraries are not strictly divided into general categories. It is required that the professionals engaged in Italian libraries should have secondary or university education. The level of their professional tasks depends on the type of library and its capacity. The competency for the development in the field of librarianship is assigned to The Ministry of Cultural and Environment Heritage as well as to its subordinate institutions (Central Institute for the Union catalogue of Italian Libraries and for Bibliographic Information, Central Institute for Book Pathology, Observatory for International Libraries Programmes.

  17. CCN Spectral Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, James G.

    2009-02-27

    Detailed aircraft measurements were made of cloud condensation nuclei (CCN) spectra associated with extensive cloud systems off the central California coast in the July 2005 MASE project. These measurements include the wide supersaturation (S) range (2-0.01%) that is important for these polluted stratus clouds. Concentrations were usually characteristic of continental/anthropogenic air masses. The most notable feature was the consistently higher concentrations above the clouds than below. CCN measurements are so important because they provide a link between atmospheric chemistry and cloud-climate effects, which are the largest climate uncertainty. Extensive comparisons throughout the eleven flights between two CCN spectrometers operated at different but overlapping S ranges displayed the precision and accuracy of these difficult spectral determinations. There are enough channels of resolution in these instruments to provide differential spectra, which produce more rigorous and precise comparisons than traditional cumulative presentations of CCN concentrations. Differential spectra are also more revealing than cumulative spectra. Only one of the eleven flights exhibited typical maritime concentrations. Average below cloud concentrations over the two hours furthest from the coast for the 8 flights with low polluted stratus was 614?233 at 1% S, 149?60 at 0.1% S and 57?33 at 0.04% S cm-3. Immediately above cloud average concentrations were respectively 74%, 55%, and 18% higher. Concentration variability among those 8 flights was a factor of two. Variability within each flight excluding distances close to the coast ranged from 15-56% at 1% S. However, CN and probably CCN concentrations sometimes varied by less than 1% over distances of more than a km. Volatility and size-critical S measurements indicated that the air masses were very polluted throughout MASE. The aerosol above the clouds was more polluted than the below cloud aerosol. These high CCN concentrations from

  18. The Memory Library

    DEFF Research Database (Denmark)

    Olesen-Bagneux, Ole

    2014-01-01

    For millennia the famous library in Hellenistic Alexandria has been praised as an epicenter of enlightenment and wisdom. And yet, a question still seems unanswered: how was its literature classified and retrieved? It is a subject that has been given surprisingly little attention by Library......- and Information Science – indeed, by scholarship in general. Furthermore, a certain way of thinking has influenced the few answers that have so far been attempted. It is as if the scholars of our era have tried to identify the modern, physical library in the Hellenistic library in Alexandria. But such an approach...... is biased in a basic way: It simply does not consider the impact of the cultural and intellectual context of the library. This article differs fundamentally, and rejects that the library was like modern ones. Accordingly, an entirely new way of understanding how the library actually worked, in terms...

  19. The participatory public library

    DEFF Research Database (Denmark)

    Rasmussen, Casper Hvenegaard

    2016-01-01

    Purpose From collection to connection has been a buzzword in the library world for more than a decade. This catchy phrase indicates that users are seen not only as borrowers, but as active participants. The aim of this paper is to investigate and analyse three questions in relation to user...... participation in public libraries in a Nordic perspective. How can participation in public libraries be characterised? Why should libraries deal with user participation? What kinds of different user participation can be identified in public libraries? Design/methodology/approach The paper uses a selection...... of theoretical approaches and practical examples to obtain a varied understanding of user participation in public libraries. Research fields outside library and information science have developed a wide range of theoretical approaches on user participation. Examples from cultural policy, museum studies...

  20. The participatory public library

    DEFF Research Database (Denmark)

    Rasmussen, Casper Hvenegaard

    2016-01-01

    of theoretical approaches and practical examples to obtain a varied understanding of user participation in public libraries. Research fields outside library and information science have developed a wide range of theoretical approaches on user participation. Examples from cultural policy, museum studies......Purpose From collection to connection has been a buzzword in the library world for more than a decade. This catchy phrase indicates that users are seen not only as borrowers, but as active participants. The aim of this paper is to investigate and analyse three questions in relation to user...... participation in public libraries in a Nordic perspective. How can participation in public libraries be characterised? Why should libraries deal with user participation? What kinds of different user participation can be identified in public libraries? Design/methodology/approach The paper uses a selection...

  1. Flight Software Math Library

    Science.gov (United States)

    McComas, David

    2013-01-01

    The flight software (FSW) math library is a collection of reusable math components that provides typical math utilities required by spacecraft flight software. These utilities are intended to increase flight software quality reusability and maintainability by providing a set of consistent, well-documented, and tested math utilities. This library only has dependencies on ANSI C, so it is easily ported. Prior to this library, each mission typically created its own math utilities using ideas/code from previous missions. Part of the reason for this is that math libraries can be written with different strategies in areas like error handling, parameters orders, naming conventions, etc. Changing the utilities for each mission introduces risks and costs. The obvious risks and costs are that the utilities must be coded and revalidated. The hidden risks and costs arise in miscommunication between engineers. These utilities must be understood by both the flight software engineers and other subsystem engineers (primarily guidance navigation and control). The FSW math library is part of a larger goal to produce a library of reusable Guidance Navigation and Control (GN&C) FSW components. A GN&C FSW library cannot be created unless a standardized math basis is created. This library solves the standardization problem by defining a common feature set and establishing policies for the library s design. This allows the libraries to be maintained with the same strategy used in its initial development, which supports a library of reusable GN&C FSW components. The FSW math library is written for an embedded software environment in C. This places restrictions on the language features that can be used by the library. Another advantage of the FSW math library is that it can be used in the FSW as well as other environments like the GN&C analyst s simulators. This helps communication between the teams because they can use the same utilities with the same feature set and syntax.

  2. Assessing Library Automation and Virtual Library Development in Four Academic Libraries in Oyo, Oyo State, Nigeria

    Science.gov (United States)

    Gbadamosi, Belau Olatunde

    2011-01-01

    The paper examines the level of library automation and virtual library development in four academic libraries. A validated questionnaire was used to capture the responses from academic librarians of the libraries under study. The paper discovers that none of the four academic libraries is fully automated. The libraries make use of librarians with…

  3. Spectral Classification of Heavily Reddened Stars by CO Absorption Strength

    Science.gov (United States)

    Garling, Christopher; Bary, Jeffrey S.; Huard, Tracy L.

    2017-01-01

    The nature of dust grains in dense molecular clouds can be explored by obtaining spectra of giant stars located behind the clouds and examining the wavelength-dependent attentuation of their light. This approach requires the intrinsic spectra of the background stars to be known, which can be achieved by determining their spectral types. In the K-band spectra of cool giant stars, several temperature-sensitive CO absorption bands serve as good spectral type indicators. Taking advantage of the SpeX Infrared Telescope Facility Spectral Library, near-infrared spectra collected with TripleSpec and the 3.5-meter ARC Telescope at Apache Point Observatory, and a previously constructed CO spectral index, we make precise spectral determinations of 20 giant stars located behind two dense cloud cores: CB188 and L429C. With spectral types in hand, we then utilize Markov Chain Monte Carlo techniques to constrain extinctions along these lines of sight. The spectral typing method will be described and assessed as well as its success at finding a couple of incorrectly spectral typed stars in the SpeX Library. Funding for this program was provided by a NSF REU grant to the Keck Northeast Astronomy Consortium and a grant from the NASA Astrophysics Data Analysis Program.

  4. A global spectral library to characterize the world's soil

    NARCIS (Netherlands)

    Viscarra Rossel, R.A.; Behrens, T.; Ben-Dor, E.; Bartholomeus, H.M.

    2016-01-01

    Soil provides ecosystem services, supports human health and habitation, stores carbon and regulates emissions of greenhouse gases. Unprecedented pressures on soil from degradation and urbanization are threatening agro-ecological balances and food security. It is important that we learn more about

  5. "We Don't Do Public Libraries Like We Used to": Attitudes to Public Library Buildings in the UK at the Start of the 21st Century

    Science.gov (United States)

    Black, Alistair

    2011-01-01

    Although the quality, performance and future of public library services in the UK is a matter of debate, there is little doubt that in recent years, despite claims relating to the emergence of a cyber-society, interest in library buildings and the library as "place" has been intense, almost matching that seen during the Carnegie era of mass public…

  6. Interaction between libraries and library users on Facebook

    OpenAIRE

    Chen, DYT; Maxwell, W.; Li, WZS; Tang, LLC; Chu, SKW

    2011-01-01

    This study adopts the mixed method research design to investigate the interaction between libraries and library users on Facebook. The research objectives are: (1) To find out the performance of Facebook as a tool for interaction between libraries and library users; (2) To find out the differences in using Facebook to interact with library users between libraries in two regions: English-speaking countries and Greater China; (3) To find out the differences between academic and public libraries...

  7. Integration of Library Services in the System of Digital Libraries

    Science.gov (United States)

    Bezdushnyj, A. N.; Kalenov, N. E.; Kouriv, P. M.; Serebryakov, V. A.

    The article is devoted to the functional extension of the Integrated System of Information Resources of RAS (ISIR RAS - RFBR 99-07-90139 project). This extension (Library Subsystem) provides integration of library services in ISIR RAS electronic libraries system. Library Subsystem implements standard library services such as information about free and ordered copies of editions, creation of the library orders for edition etc. The Library Subsystem is an integrated solution; it's based on ISIR data model and technologies.

  8. News from the Library

    CERN Multimedia

    CERN Library

    2010-01-01

    The LHC Library to be merged with the Central Library. Not everyone knows that CERN Scientific Information Service currently counts three physical libraries on site. The Central Library is located in Building 52 and there are two satellite libraries located respectively in building 30 (the LHC Library) and in building 864 on Prévessin site (the SPS Library). Moreover, the Legal Service Library is located in Building 60. In the past, there have been at CERN up to 6 satellite libraries; they were essential at a time when information was only in paper form and having multiple copies of documents located in several places at CERN was useful to facilitate scientific research. Today, this need is less critical as most of our resources are online. That is why, following a SIPB (Scientific Information Policy Board) decision, the collections of the LHC Library will be merged this summer with the Central collection. This reorganization and centralization of resources will improve loan services. The SP...

  9. LIBRARY SURVEY 2001

    CERN Multimedia

    2001-01-01

    The primary role of the library is to make sure that you can do YOUR work in the most efficient way possible. To ensure that we continue to match our services to your information needs, the library regularly gathers the views and opinions of its readers in a variety of ways, [link for e-version: http://library/library_general/statistics/library_statistics_ surveys.html], including user surveys. The last survey was carried out in 1996. One of the most visible results of that survey was the extension of the library desk service until seven o'clock in the evening, to meet the demand for greater access to library materials. Now the 'electronic library' is becoming more important than the physical one, we feel it is once again time to ensure that we are providing the services and information you need, in the most effective way possible. We also want to make sure you are aware of the full range of services that the library provides. Please spare just a few minutes to fill out our survey at http://library.cern.ch/su...

  10. Visualizations for Digital Libraries

    Directory of Open Access Journals (Sweden)

    Gang Wan

    2006-06-01

    Full Text Available The concept of digital libraries is familiar to both librarians and library patrons today. These new libraries have broken the limits of space and distance by delivering information in various formats via the Internet. Since most digital libraries contain a colossal amount of information, it is critical to design more user-friendly interfaces to explore, understand, and manage their content. One important technique for designing such interfaces is information visualization. Although computer-aided information visualization is a relatively new research area, numerous visualization applications already exist in various fields today. Furthermore, many library professionals are also starting to realize that combining information visualization techniques and current library technologies, such as digital libraries, can help library users find information more effectively and efficiently. This article first discusses three major tasks that most visualization for digital libraries emphasize, and then introduces several current applications of information visualization for digital libraries.

  11. SpectralPlasmaSolver: a Spectral Code for Multiscale Simulations of Collisionless, Magnetized Plasmas

    Science.gov (United States)

    Vencels, Juris; Delzanno, Gian Luca; Manzini, Gianmarco; Markidis, Stefano; Peng, Ivy Bo; Roytershteyn, Vadim

    2016-05-01

    We present the design and implementation of a spectral code, called SpectralPlasmaSolver (SPS), for the solution of the multi-dimensional Vlasov-Maxwell equations. The method is based on a Hermite-Fourier decomposition of the particle distribution function. The code is written in Fortran and uses the PETSc library for solving the non-linear equations and preconditioning and the FFTW library for the convolutions. SPS is parallelized for shared- memory machines using OpenMP. As a verification example, we discuss simulations of the two-dimensional Orszag-Tang vortex problem and successfully compare them against a fully kinetic Particle-In-Cell simulation. An assessment of the performance of the code is presented, showing a significant improvement in the code running-time achieved by preconditioning, while strong scaling tests show a factor of 10 speed-up using 16 threads.

  12. The JCMT Spectral Legacy Survey

    CERN Document Server

    Plume, R; Helmich, F; Van der Tak, F F S; Roberts, H; Bowey, J; Buckle, J; Butner, H; Caux, E; Ceccarelli, C; Van Dishoeck, E F; Friberg, P; Gibb, A G; Hatchell, J; Hogerheijde, M R; Matthews, H; Millar, T; Mitchell, G; Moore, T J T; Ossenkopf, V; Rawlings, J; Richer, J; Roellig, M; Schilke, P; Spaans, M; Tielens, A G G M; Thompson, M A; Viti, S; Weferling, B; White, G J; Wouterloot, J; Yates, J; Zhu, M; White, Glenn J.

    2006-01-01

    Stars form in the densest, coldest, most quiescent regions of molecular clouds. Molecules provide the only probes which can reveal the dynamics, physics, chemistry and evolution of these regions, but our understanding of the molecular inventory of sources and how this is related to their physical state and evolution is rudimentary and incomplete. The Spectral Legacy Survey (SLS) is one of seven surveys recently approved by the JCMT Board. Starting in 2007, the SLS will produce a spectral imaging survey of the content and distribution of all the molecules detected in the 345 GHz atmospheric window (between 332 GHz and 373 GHz) towards a sample of 5 sources. Our intended targets are: a low mass core (NGC1333 IRAS4), 3 high mass cores spanning a range of star forming environments and evolutionary states (W49, AFGL2591, and IRAS20126), and a PDR (the Orion Bar). The SLS will use the unique spectral imaging capabilities of HARP-B/ACSIS to study the molecular inventory and the physical structure of these objects, w...

  13. SpeX spectroscopy of unresolved very low mass binaries. II. Identification of 14 candidate binaries with late-M/early-L and T dwarf components

    Energy Technology Data Exchange (ETDEWEB)

    Bardalez Gagliuffi, Daniella C.; Burgasser, Adam J.; Nicholls, Christine P. [Center for Astrophysics and Space Sciences, University of California, San Diego, 9500 Gilman Drive, Mail Code 0424, La Jolla, CA 92093 (United States); Gelino, Christopher R. [NASA Exoplanet Science Institute, Mail Code 100-22, California Institute of Technology, 770 South Wilson Avenue, Pasadena, CA 91125 (United States); Looper, Dagny L. [School of Mathematics and Physics, The University of Queensland, Brisbane, QLD 4072 (Australia); Schmidt, Sarah J. [Department of Physics and Astronomy, Hunter College, City University of New York, 695 Park Avenue, New York, NY 10065 (United States); Cruz, Kelle [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024 (United States); West, Andrew A. [Department of Physics and Astronomy, University of Delaware, 104 The Green, Newark, DE 19716 (United States); Gizis, John E. [Department of Physics and Astronomy, Western University, London, ON N6A 3K7 (Canada); Metchev, Stanimir, E-mail: daniella@physics.ucsd.edu [Infrared Processing and Analysis Center, Mail Code 100-22, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

    2014-10-20

    Multiplicity is a key statistic for understanding the formation of very low mass (VLM) stars and brown dwarfs. Currently, the separation distribution of VLM binaries remains poorly constrained at small separations (≤1 AU), leading to uncertainty in the overall binary fraction. We approach this problem by searching for late-M/early-L plus T dwarf spectral binaries whose combined light spectra exhibit distinct peculiarities, allowing for separation-independent identification. We define a set of spectral indices designed to identify these systems, and we use a spectral template fitting method to confirm and characterize spectral binary candidates from a library of 815 spectra from the SpeX Prism Spectral Libraries. We present 11 new binary candidates, confirm 3 previously reported candidates, and rule out 2 previously identified candidates, all with primary and secondary spectral types in the range M7-L7 and T1-T8, respectively. We find that subdwarfs and blue L dwarfs are the primary contaminants in our sample and propose a method for segregating these sources. If confirmed by follow-up observations, these systems may add to the growing list of tight separation binaries, whose orbital properties may yield further insight into brown dwarf formation scenarios.

  14. Construction and Analysis of N-phosphoryl Peptide Libraries

    Institute of Scientific and Technical Information of China (English)

    Shu Xia CAO; Jian Chen ZHANG; Ming Yu NIU; Kui LU; Xin Cheng LIAO; Yu Fen ZHAO

    2004-01-01

    N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction.

  15. Spectral similarity approach for mapping turbidity of an inland waterbody

    Science.gov (United States)

    Garg, Vaibhav; Senthil Kumar, A.; Aggarwal, S. P.; Kumar, Vinay; Dhote, Pankaj R.; Thakur, Praveen K.; Nikam, Bhaskar R.; Sambare, Rohit S.; Siddiqui, Asfa; Muduli, Pradipta R.; Rastogi, Gurdeep

    2017-07-01

    Turbidity is an important quality parameter of water from its optical property point of view. It varies spatio-temporally over large waterbodies and its well distributed measurement on field is tedious and time consuming. Generally, normalized difference turbidity index (NDTI), or band ratio, or regression analysis between turbidity concentration and band reflectance, approaches have been adapted to retrieve turbidity using multispectral remote sensing data. These techniques usually provide qualitative rather than quantitative estimates of turbidity. However, in the present study, spectral similarity analysis, between the spectral characteristics of spaceborne hyperspectral remote sensing data and spectral library generated on field, was carried out to quantify turbidity in the part of Chilika Lake, Odisha, India. Spatial spectral contextual image analysis, spectral angle mapper (SAM) technique was evaluated for the same. The SAM spectral matching technique has been widely used in geological application (mineral mapping), however, the application of this kind of techniques is limited in water quality studies due to non-availability of reference spectral libraries. A spectral library was generated on field for the different concentrations of turbidity using well calibrated instruments like field spectro-radiometer, turbidity meter and hand held global positioning system. The field spectra were classified into 7 classes of turbidity concentration as 100 NTU for analysis. Analysis reveal that at each location in the lake under consideration, the field spectra matched with the image spectra with SAM score of 0.8 and more. The observed turbidity at each location was also very much falling in the estimated turbidity class range. It was observed that the spectral similarity approach provides more quantitative estimate of turbidity as compared to NDTI.

  16. The Library International Partnerweek 2011

    DEFF Research Database (Denmark)

    Presentation at the Library International Partnerweek, held at Copenhagen Technical Library at the Copenhagen University College of Engineering. Participant: Ms. Carmen Priesto Estravid from Madrid Technical University, E.U.I.T. Obras Públicas, Library. Spain Ms.Tuulikki Hattunen from TUAS Library....... Finland Ms. Anitta Ôrm from Kemi-Tornio UAS Library. Finland Mr. Manfred Walter from HTW-Berlin. Germany Mr. Peter Hald from Copenhagen Technical Library. Denmark Mr. Ole Micahelsen from Copenhagen Technical Library. Denmark...

  17. libdrdc: software standards library

    Science.gov (United States)

    Erickson, David; Peng, Tie

    2008-04-01

    This paper presents the libdrdc software standards library including internal nomenclature, definitions, units of measure, coordinate reference frames, and representations for use in autonomous systems research. This library is a configurable, portable C-function wrapped C++ / Object Oriented C library developed to be independent of software middleware, system architecture, processor, or operating system. It is designed to use the automatically-tuned linear algebra suite (ATLAS) and Basic Linear Algebra Suite (BLAS) and port to firmware and software. The library goal is to unify data collection and representation for various microcontrollers and Central Processing Unit (CPU) cores and to provide a common Application Binary Interface (ABI) for research projects at all scales. The library supports multi-platform development and currently works on Windows, Unix, GNU/Linux, and Real-Time Executive for Multiprocessor Systems (RTEMS). This library is made available under LGPL version 2.1 license.

  18. Academic Libraries, 2000. E.D. Tabs.

    Science.gov (United States)

    Carey, Nancy; Justh, Natalie M.; Williams, Jeffrey W.

    This report discusses the state of academic libraries in 2000. It defines "academic library" as well as discusses library services, library collections, library staff, library expenditures, and electronic services. (Author/AMT)

  19. The Use of Geometric Diversity for Spectral Dominance in Underground Imaging

    Science.gov (United States)

    2009-01-01

    licensed use limited to: WASHINGTON UNIVERSITY LIBRARIES. Downloaded on October 6, 2009 at 15:06 from IEEE Xplore . Restrictions apply. Report Documentation...LIBRARIES. Downloaded on October 6, 2009 at 15:06 from IEEE Xplore . Restrictions apply. Where HL denotes the adjoint of L , and β is the...WASHINGTON UNIVERSITY LIBRARIES. Downloaded on October 6, 2009 at 15:06 from IEEE Xplore . Restrictions apply. spectral content of ( )’δε r is limited

  20. KAERI photonuclear library

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jong Hwa; Lee, Young Ouk; Han, Yin Iu

    2000-03-01

    This report contains summary information and figures depicting the KAERI photonuclear data library that extends up to 140 MeV of incident photon. The library consists of 143 isotopes from C-12 to Bi-209, providing the photoabsorption cross section and the emission spectra for neutron, proton, deuteron, triton, alpha particles, and all residual nuclides in ENDF6 format. The contents of this report and ENDF-6 format data library are available at http://atom.kaeri.re.kr/.

  1. The CERN Library

    CERN Multimedia

    Hester, Alec G

    1968-01-01

    Any advanced research centre needs a good Library. It can be regarded as a piece of equipment as vital as any machine. At the present time, the CERN Library is undergoing a number of modifications to adjust it to the changing scale of CERN's activities and to the ever increasing flood of information. This article, by A.G. Hester, former Editor of CERN COURIER who now works in the Scientific Information Service, describes the purposes, methods and future of the CERN Library.

  2. Open Digital Libraries

    OpenAIRE

    2002-01-01

    Digital Libraries (DLs) are software systems specifically designed to assist users in information seeking activities. Stemming from the intersection of library sciences and computer networking, traditional DL systems impose library philosophies of structure and management on the sprawling collections of data that are made possible through the Internet. DLs evolve to keep pace with innovation on the Internet so there is little standardization in the architecture of such systems. However, ...

  3. The Personal Virtual Library

    CERN Document Server

    Le Meur, Jean-Yves

    1998-01-01

    Looking for "library" in the usual search engines of the World Wide Web gives: "Infoseek found 3,593,126 pages containing the word library" and it nicely proposes: "Search only within these 3,59 3,126 pages ?" "Yahoo! Found 1299 categories and 8669 sites for library" "LycOs: 1-10 von 512354 relevanten Ergebnissen" "AltaVista: About 14830527 documents match your query" and at the botto m: "Word count: library: 15466897" ! Excite: Top 10 matches and it does not say how many can be browsed... "Library" on the World Wide Web is really popular. At least fiveteen million pages ar e supposed to contain this word. Half of them may have disappeared by now but one more hit will be added once the search robots will have indexed this document ! The notion of Personal Library i s a modest attempt, in a small environment like a library, to give poor users lost in cyber-libraries the opportunity to keep their own private little shelves - virtually. In this paper, we will l ook at the usual functionalities of library systems...

  4. NEIC Library Services

    Science.gov (United States)

    The National Enforcement Investigation Center (NEIC) Environmental Forensic Library partners with NEIC's forensic scientists to retrieve, validate and deliver information to develop methods, defensible regulations, and environmental measurements.

  5. Extension of least squares spectral resolution algorithm to high-resolution lipidomics data.

    Science.gov (United States)

    Zeng, Ying-Xu; Mjøs, Svein Are; David, Fabrice P A; Schmid, Adrien W

    2016-03-31

    Lipidomics, which focuses on the global study of molecular lipids in biological systems, has been driven tremendously by technical advances in mass spectrometry (MS) instrumentation, particularly high-resolution MS. This requires powerful computational tools that handle the high-throughput lipidomics data analysis. To address this issue, a novel computational tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. The algorithm features the customized generation of a lipid compound library and mass spectral library, which covers the major lipid classes such as glycerolipids, glycerophospholipids and sphingolipids. Next, the algorithm performs least squares resolution of spectra and chromatograms based on the theoretical isotope distribution of molecular ions, which enables automated identification and quantification of molecular lipid species. Currently, this methodology supports analysis of both high and low resolution MS as well as liquid chromatography-MS (LC-MS) lipidomics data. The flexibility of the methodology allows it to be expanded to support more lipid classes and more data interpretation functions, making it a promising tool in lipidomic data analysis.

  6. An updated MILES stellar library and stellar population models (Research Note)

    NARCIS (Netherlands)

    Falcon-Barroso, J.; Sanchez-Blazquez, P.; Vazdekis, A.; Ricciardelli, E.; Cardiel, N.; Cenarro, A. J.; Gorgas, J.; Peletier, R. F.

    Aims: We present a number of improvements to the MILES library and stellar population models. We correct some small errors in the radial velocities of the stars, measure the spectral resolution of the library and models more accurately, and give a better absolute flux calibration of the models.

  7. Optical Disc Applications in Libraries.

    Science.gov (United States)

    Andre, Pamela Q. J.

    1989-01-01

    Discusses a variety of library applications of optical disc storage technology, including CD-ROM, digital videodisc, and WORM. Research and development projects at the Library of Congress, National Library of Medicine, and National Agricultural Library are described, products offered by library networks are reviewed, and activities in academic and…

  8. Public Relations in Special Libraries.

    Science.gov (United States)

    Rutkowski, Hollace Ann; And Others

    1991-01-01

    This theme issue includes 11 articles on public relations (PR) in special libraries. Highlights include PR at the Special Libraries Association (SLA); sources for marketing research for libraries; developing a library image; sample PR releases; brand strategies for libraries; case studies; publicizing a consortium; and a bibliography of pertinent…

  9. Future-Proof Your Library

    Science.gov (United States)

    Miller, Rebecca

    2008-01-01

    This article presents an excerpt of Library Journal's (LJ's) Movers & Shakers ideas on how to ensure a vital library for the future. Several identify a disconnect between what librarians and libraries do and what users think they do. Mending this gap, they say, would transform library recruitment and library support. While specific insights on…

  10. Music Libraries: Centralization versus Decentralization.

    Science.gov (United States)

    Kuyper-Rushing, Lois

    2002-01-01

    Considers the decision that branch libraries, music libraries in particular, have struggled with concerning a centralized location in the main library versus a decentralized collection. Reports on a study of the Association of Research Libraries that investigated the location of music libraries, motivation for the location, degrees offered,…

  11. In silico fragmentation for computer assisted identification of metabolite mass spectra

    Directory of Open Access Journals (Sweden)

    Müller-Hannemann Matthias

    2010-03-01

    Full Text Available Abstract Background Mass spectrometry has become the analytical method of choice in metabolomics research. The identification of unknown compounds is the main bottleneck. In addition to the precursor mass, tandem MS spectra carry informative fragment peaks, but the coverage of spectral libraries of measured reference compounds are far from covering the complete chemical space. Compound libraries such as PubChem or KEGG describe a larger number of compounds, which can be used to compare their in silico fragmentation with spectra of unknown metabolites. Results We created the MetFrag suite to obtain a candidate list from compound libraries based on the precursor mass, subsequently ranked by the agreement between measured and in silico fragments. In the evaluation MetFrag was able to rank most of the correct compounds within the top 3 candidates returned by an exact mass query in KEGG. Compared to a previously published study, MetFrag obtained better results than the commercial MassFrontier software. Especially for large compound libraries, the candidates with a good score show a high structural similarity or just different stereochemistry, a subsequent clustering based on chemical distances reduces this redundancy. The in silico fragmentation requires less than a second to process a molecule, and MetFrag performs a search in KEGG or PubChem on average within 30 to 300 seconds, respectively, on an average desktop PC. Conclusions We presented a method that is able to identify small molecules from tandem MS measurements, even without spectral reference data or a large set of fragmentation rules. With today's massive general purpose compound libraries we obtain dozens of very similar candidates, which still allows a confident estimate of the correct compound class. Our tool MetFrag improves the identification of unknown substances from tandem MS spectra and delivers better results than comparable commercial software. MetFrag is available through a web

  12. New Library Buildings and Library Reconstructions

    Directory of Open Access Journals (Sweden)

    Steen Bille Larsen

    2002-07-01

    Full Text Available Visits to libraries have always been an important part of the LIBER Architecture Group Seminars, as they add practice, concrete examples of success and mistakes to the theory of the seminar presentations. The programme of the Leipzig seminar thus offered quite a few library visits: Universitätsbibliothek Leipzig, Thüringer Universitäts- und Landesbibliothek, Jena, Universitäts- und Forschungsbibliothek Erfurt, Herzogin-Anna-Amalia-Bibliothek, Weimar, Universitätsbibliothek der Bauhaus-Universität Weimar, Deutsche Bücherei, Leipzig and Sächsische Landesbibliothek – Staatsund Universitätsbibliothek, Dresden. The following is a short report about the libraries visited during the week. The reports are combined with quotations from the libraries’ presentation of their building projects and in some cases also with facts and figures.

  13. Library Systems: FY 2012 Public Libraries Survey (Administrative Entity)

    Data.gov (United States)

    Institute of Museum and Library Services — Find key information on library systems around the United States.These data include imputed values for libraries that did not submit information in the FY 2012 data...

  14. Library Systems: FY 2014 Public Libraries Survey (Administrative Entity Data)

    Data.gov (United States)

    Institute of Museum and Library Services — Find key information on library systems around the United States.These data include imputed values for libraries that did not submit information in the FY 2014 data...

  15. Library Systems: FY 2013 Public Libraries Survey (Administrative Entity)

    Data.gov (United States)

    Institute of Museum and Library Services — Find key information on library systems around the United States.These data include imputed values for libraries that did not submit information in the FY 2013 data...

  16. Sequencing of Oligourea Foldamers by Tandem Mass Spectrometry

    Science.gov (United States)

    Bathany, Katell; Owens, Neil W.; Guichard, Gilles; Schmitter, Jean-Marie

    2013-03-01

    This study is focused on sequence analysis of peptidomimetic helical oligoureas by means of tandem mass spectrometry, to build a basis for de novo sequencing for future high-throughput combinatorial library screening of oligourea foldamers. After the evaluation of MS/MS spectra obtained for model compounds with either MALDI or ESI sources, we found that the MALDI-TOF-TOF instrument gave more satisfactory results. MS/MS spectra of oligoureas generated by decay of singly charged precursor ions show major ion series corresponding to fragmentation across both CO-NH and N'H-CO urea bonds. Oligourea backbones fragment to produce a pattern of a, x, b, and y type fragment ions. De novo decoding of spectral information is facilitated by the occurrence of low mass reporter ions, representative of constitutive monomers, in an analogous manner to the use of immonium ions for peptide sequencing.

  17. AGNfitter: A Bayesian MCMC approach to fitting spectral energy distributions of AGN

    CERN Document Server

    Rivera, Gabriela Calistro; Hennawi, Joseph F; Hogg, David W

    2016-01-01

    We present AGNfitter, a publicly available open-source algorithm implementing a fully Bayesian Markov Chain Monte Carlo method to fit the spectral energy distributions (SEDs) of active galactic nuclei (AGN) from the sub-mm to the UV, allowing one to robustly disentangle the physical processes responsible for their emission. AGNfitter makes use of a large library of theoretical, empirical, and semi-empirical models to characterize both the nuclear and host galaxy emission simultaneously. The model consists of four physical emission components: an accretion disk, a torus of AGN heated dust, stellar populations, and cold dust in star forming regions. AGNfitter determines the posterior distributions of numerous parameters that govern the physics of AGN with a fully Bayesian treatment of errors and parameter degeneracies, allowing one to infer integrated luminosities, dust attenuation parameters, stellar masses, and star formation rates. We tested AGNfitter's performace on real data by fitting the SEDs of a sample...

  18. Compressive Spectral Renormalization Method

    CERN Document Server

    Bayindir, Cihan

    2016-01-01

    In this paper a novel numerical scheme for finding the sparse self-localized states of a nonlinear system of equations with missing spectral data is introduced. As in the Petviashivili's and the spectral renormalization method, the governing equation is transformed into Fourier domain, but the iterations are performed for far fewer number of spectral components (M) than classical versions of the these methods with higher number of spectral components (N). After the converge criteria is achieved for M components, N component signal is reconstructed from M components by using the l1 minimization technique of the compressive sampling. This method can be named as compressive spectral renormalization (CSRM) method. The main advantage of the CSRM is that, it is capable of finding the sparse self-localized states of the evolution equation(s) with many spectral data missing.

  19. Library Consortia in Hungary

    Science.gov (United States)

    Csajbok, Edit; Szluka, Peter; Vasas, Livia

    2012-01-01

    During the last two decades many Hungarian libraries have developed considerably, beyond what was considered possible prior to 1989 and the beginning of events signaling the end of Communism in the country. Some of the modernization of library services has been realized through participation in cooperative agreements. Many smaller and larger…

  20. Library Classification 2020

    Science.gov (United States)

    Harris, Christopher

    2013-01-01

    In this article the author explores how a new library classification system might be designed using some aspects of the Dewey Decimal Classification (DDC) and ideas from other systems to create something that works for school libraries in the year 2020. By examining what works well with the Dewey Decimal System, what features should be carried…

  1. Library Reference Services.

    Science.gov (United States)

    Miller, Constance; And Others

    1985-01-01

    Seven articles on library reference services highlight reference obsolescence in academic libraries, major studies of unobtrusive reference tests, methods for evaluating reference desk performance, reference interview evaluation, problems of reference desk control, online searching by end users, and reference collection development in…

  2. Weeding Library Collections.

    Science.gov (United States)

    Slote, Stanley J.

    This work, based on two recent research projects in the weeding of library collections and the identification of core collections, provides a comprehensive summary of the literature and research on these topics. It also presents practical guidance in weeding for the professional librarian or for the library school student. The book is divided into…

  3. Trotsky's Vision of Libraries.

    Science.gov (United States)

    Baker, William; Hurych, Jitka

    1991-01-01

    Discusses Leon Trotsky's views on libraries, librarians, and librarianship in Soviet society in the 1920s as expressed in a speech, "Leninism and Library Work." Topics discussed include role of librarian in promoting literacy, including the use of maps and reference books to explain newspaper stories; the selection of books; and fighting…

  4. Basic Library List.

    Science.gov (United States)

    Duren, William L., Jr.

    Reported is an initial attempt to define a minimal college mathematics library. Included is a list of some 300 books, from which approximately 170 are to be chosen to form a basic library in undergraduate mathematics. The areas provided for in this list include Algebra, Analysis, Applied Mathematics, Geometry, Topology, Logic, Foundations and Set…

  5. Running the Library Race

    Directory of Open Access Journals (Sweden)

    Erica Jesonis

    2012-09-01

    Full Text Available In Brief: This article draws a parallel between fatigued runners and overworked librarians, proposing that libraries need to pace work more effectively to avoid burnout. Through an exploration of cognitive science, organizational psychology, and practical examples, guest author Erica Jesonis offers considerations for improving productivity and reducing stress within our fast-paced library culture. I recently [...

  6. Academic Libraries in Japan

    Science.gov (United States)

    Cullen, Rowena; Nagata, Haruki

    2008-01-01

    Academic libraries in Japan are well resourced by international standards, and support Japan's internationally recognized research capability well, but there are also ways in which they reflect Japan's strong bureaucratic culture. Recent changes to the status of national university libraries have seen a new interest in customer service, and…

  7. Dumping the "Library."

    Science.gov (United States)

    Crowley, Bill

    1998-01-01

    Discusses an alternative to abandoning the word "library" for "information" in graduate education. Recommends patient, consistent effort by library- and information-science educators to convince academic librarians that if they accept the standards of the teaching/research faculty, including the need to earn a Ph.D., it will raise the prestige of…

  8. Academic Libraries in Japan

    Science.gov (United States)

    Cullen, Rowena; Nagata, Haruki

    2008-01-01

    Academic libraries in Japan are well resourced by international standards, and support Japan's internationally recognized research capability well, but there are also ways in which they reflect Japan's strong bureaucratic culture. Recent changes to the status of national university libraries have seen a new interest in customer service, and…

  9. Libraries on the Way

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An NGO campaigns to help rural students find the joy of reading Tan Li joined the Gan Quan Library,a Trural library in Chengde,north China’s Hebei Province,after graduating from the Shanxi University of Finance and Economics in July.

  10. Redefining Services to Libraries.

    Science.gov (United States)

    Hearty, John; Smith, Robert

    1993-01-01

    Describes the strategic plan developed for reference services offered by OCLC Online Computer Library Center to provide easier access to, and use of, information and knowledge. Topics addressed include the environment of libraries and publishers, including budgets, networks, and pricing, and future plans, including an emphasis on online products.…

  11. Library Media Services Handbook.

    Science.gov (United States)

    Winnipeg School Div. Number 1, Manitoba (Canada).

    This 1991 edition of the handbook for Winnipeg School Division Number 1 school library media programs presents detailed program guidelines, objectives, philosophies, and goals in five major sections: (1) Library Policy and Practices (statement of the division's educational philosophy and goals, philosophy and goals of the division's library…

  12. Prison Libraries: Bibliography.

    Science.gov (United States)

    Gillespie, David M.

    An Alphabetically arranged bibliography, listing 485 entries representing 518 citations taken from "Poole's Index to Periodical Literature" 1802-1906, "Cannon's Bibliography of Library Economy," and "Library Literature" 1921 to mid-1970. Other sources used include: The Index to the Journal of Correctional Education; ten bibliographies taken from…

  13. Brighton's Toy Library.

    Science.gov (United States)

    Rand, Duncan

    1978-01-01

    Describes a successful toy library in a public library in terms of staffing and patrons, toy selection, toy breakage problem, and sources of toys. In addition to children, users include an adult literacy group, a school for the mentally handicapped, the local social services department, and home for the elderly. (JAB)

  14. Merchandising Techniques and Libraries.

    Science.gov (United States)

    Green, Sylvie A.

    1981-01-01

    Proposes that libraries employ modern booksellers' merchandising techniques to improve circulation of library materials. Using displays in various ways, the methods and reasons for weeding out books, replacing worn book jackets, and selecting new books are discussed. Suggestions for learning how to market and 11 references are provided. (RBF)

  15. Libraries at the Ready

    Science.gov (United States)

    Celano, Donna C.; Neuman, Susan B.

    2016-01-01

    Because English language learners enter kindergarten at a distinct disadvantage, Celano and Neuman examine the role public libraries can play in rallying around these young children to better prepare them for school. The authors document a new program called Every Child Ready to Read, which recently launched in 4,000 public libraries across the…

  16. Small Public Library Management

    Science.gov (United States)

    Pearlmutter, Jane; Nelson, Paul

    2012-01-01

    Anyone at the helm of a small public library knows that every little detail counts. But juggling the responsibilities that are part and parcel of the job is far from easy. Finally, here's a handbook that includes everything administrators need to keep a handle on library operations, freeing them up to streamline and improve how the organization…

  17. Online Library Videos

    Science.gov (United States)

    Power, June

    2010-01-01

    One of the challenges of access services is letting patrons know what one has to offer at his or her library, and then communicating how they may avail themselves of those services. Increasingly, libraries are doing this through more than the traditional handouts and newsletters, but also through blogs, Facebook pages, podcasts, and videos. This…

  18. The academic library network

    Directory of Open Access Journals (Sweden)

    Jacek Wojciechowski

    2012-01-01

    Full Text Available The efficiency of libraries, academic libraries in particular, necessitates organizational changes facilitating or even imposing co-operation. Any structure of any university has to have an integrated network of libraries, with an appropriate division of work, and one that is consolidated as much as it is possible into medium-size or large libraries. Within thus created network, a chance arises to centralize the main library processes based on appropriate procedures in the main library, highly specialized, more effective and therefore cheaper in operation, including a co-ordination of all more important endeavours and tasks. Hierarchically subordinated libraries can be thus more focused on performing their routine service, more and more frequently providing for the whole of the university, and being able to adjust to changeable requirements and demands of patrons and of new tasks resulting from the new model of the university operation. Another necessary change seems to be a universal implementation of an ov rall programme framework that would include all services in the university’s library networks.

  19. Homelessness in Public Libraries

    Science.gov (United States)

    Wong, Yi Ling

    2009-01-01

    This paper takes a theoretical and practical approach in defining the "problem" of homelessness in libraries. The author examines three fundamental problems on homelessness. The three fundamental questions are: (a) Who are the homeless? (b) Why are they homeless? (c) What are their information needs in libraries? These questions are important in…

  20. Library Classification 2020

    Science.gov (United States)

    Harris, Christopher

    2013-01-01

    In this article the author explores how a new library classification system might be designed using some aspects of the Dewey Decimal Classification (DDC) and ideas from other systems to create something that works for school libraries in the year 2020. By examining what works well with the Dewey Decimal System, what features should be carried…

  1. The Memory Library

    DEFF Research Database (Denmark)

    Olesen-Bagneux, Ole

    2014-01-01

    of classification and retrieval processes is presented. The key element is to understand the library both as a physical structure and as a structure in the memory of the Alexandrian scholars. In this article, these structures are put together so to propose a new interpretation of the library....

  2. The other spectral flow

    CERN Document Server

    Gato-Rivera, Beatriz; Gato-Rivera, Beatriz; Rosado, Jose Ignacio

    1995-01-01

    Recently we showed that the spectral flow acting on the N=2 twisted topological theories gives rise to a topological algebra automorphism. Here we point out that the untwisting of that automorphism leads to a spectral flow on the untwisted N=2 superconformal algebra which is different from the usual one. This "other" spectral flow does not interpolate between the chiral ring and the antichiral ring. In particular, it maps the chiral ring into the chiral ring and the antichiral ring into the antichiral ring. We discuss the similarities and differences between both spectral flows. We also analyze their action on null states.

  3. Extension of least squares spectral resolution algorithm to high-resolution lipidomics data

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Ying-Xu [Department of Chemistry, University of Bergen, PO Box 7803, N-5020 Bergen (Norway); Mjøs, Svein Are, E-mail: svein.mjos@kj.uib.no [Department of Chemistry, University of Bergen, PO Box 7803, N-5020 Bergen (Norway); David, Fabrice P.A. [Bioinformatics and Biostatistics Core Facility, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL) and Swiss Institute of Bioinformatics (SIB), Lausanne (Switzerland); Schmid, Adrien W. [Proteomics Core Facility, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne (Switzerland)

    2016-03-31

    Lipidomics, which focuses on the global study of molecular lipids in biological systems, has been driven tremendously by technical advances in mass spectrometry (MS) instrumentation, particularly high-resolution MS. This requires powerful computational tools that handle the high-throughput lipidomics data analysis. To address this issue, a novel computational tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. The algorithm features the customized generation of a lipid compound library and mass spectral library, which covers the major lipid classes such as glycerolipids, glycerophospholipids and sphingolipids. Next, the algorithm performs least squares resolution of spectra and chromatograms based on the theoretical isotope distribution of molecular ions, which enables automated identification and quantification of molecular lipid species. Currently, this methodology supports analysis of both high and low resolution MS as well as liquid chromatography-MS (LC-MS) lipidomics data. The flexibility of the methodology allows it to be expanded to support more lipid classes and more data interpretation functions, making it a promising tool in lipidomic data analysis. - Highlights: • A flexible strategy for analyzing MS and LC-MS data of lipid molecules is proposed. • Isotope distribution spectra of theoretically possible compounds were generated. • High resolution MS and LC-MS data were resolved by least squares spectral resolution. • The method proposed compounds that are likely to occur in the analyzed samples. • The proposed compounds matched results from manual interpretation of fragment spectra.

  4. Marketing and health libraries.

    Science.gov (United States)

    Wakeham, Maurice

    2004-12-01

    To present an overview of the concepts of marketing and to examine ways in which they can be applied to health libraries. A review was carried out of literature relating to health libraries using LISA, CINAHL, BNI and Google. Marketing is seen as a strategic management activity aimed at developing customer relationships. Concepts such as the 'four Ps' (product, price, place and promotion), marketing plans, the marketing mix, segmentation, promotion and evaluation are identified and discussed in relation to health libraries. In increasingly complex health service and information environments, the marketing and promotion of library services is becoming more important if those services are to justify the resources given to them. Marketing techniques are equally applicable to physical and digital library services.

  5. Free Library Data?

    Directory of Open Access Journals (Sweden)

    Raymond Bérard

    2011-02-01

    Full Text Available As library materials are catalogued by public organisations and librarians are active promoters of the principles of open access, one would expect library data to be freely available to all. Yet this is not the case. Why then do so few libraries make their data available free of charge? This article reviews the diverging, often restrictive policies and the interests (commercial and strategic at stake. It presents a panorama of the current situation, the actors and interests involved. It addresses the legal aspects and the obstacles and it shows how data produced by libraries can be made freely available to other knowledge organisations while retaining and developing the collective organisations and services built by library networks over the years. The aim of the ‘free the data movement’ is to share and reuse bibliographic data in a new ecosystem where all the actors are involved, both users and providers, not just librarians.

  6. Motivation and library management

    Directory of Open Access Journals (Sweden)

    Tatjana Likar

    2000-01-01

    Full Text Available The present article deals with motivation, its relation to management and its role and use in librarianship in our country and abroad. The countries where librarianship is well developed started to deal with library management and questions of motivation of library workers decades ago, whereas elsewhere the subject is at its start. The prerequisite for modern policy making is attention to the elements of modern library management. Librarians, library managers and directors of libraries should create a work environment providing long term satisfaction with work by means of certain knowledge and tools. The level of motivation of the staff is influenced by the so called higher factors deriving from the work process itself and related to work contents: achieve¬ment, recognition, trust and work itself. Extrinsic factors (income, interpersonal relations, technology of administration, company policy, working conditions, work con¬trol, personal security, job security and position... should exercise lesser impact on the level of motivation.

  7. EPA Library Network Communication Strategies

    Science.gov (United States)

    To establish Agency-wide procedures for the EPA National Library Network libraries to communicate, using a range of established mechanisms, with other EPA libraries, EPA staff, organizations and the public.

  8. Library Legislation: Some General Considerations

    Science.gov (United States)

    Ladenson, Alex

    1970-01-01

    Library service has become a concern of government at all levels with each having its specific role to play. This introductory statement to this issue of Library Trends" indicates the major substantive areas of library legislation. (Author/NH)

  9. Spectral classification using convolutional neural networks

    CERN Document Server

    Hála, Pavel

    2014-01-01

    There is a great need for accurate and autonomous spectral classification methods in astrophysics. This thesis is about training a convolutional neural network (ConvNet) to recognize an object class (quasar, star or galaxy) from one-dimension spectra only. Author developed several scripts and C programs for datasets preparation, preprocessing and postprocessing of the data. EBLearn library (developed by Pierre Sermanet and Yann LeCun) was used to create ConvNets. Application on dataset of more than 60000 spectra yielded success rate of nearly 95%. This thesis conclusively proved great potential of convolutional neural networks and deep learning methods in astrophysics.

  10. On Longitudinal Spectral Coherence

    DEFF Research Database (Denmark)

    Kristensen, Leif

    1979-01-01

    It is demonstrated that the longitudinal spectral coherence differs significantly from the transversal spectral coherence in its dependence on displacement and frequency. An expression for the longitudinal coherence is derived and it is shown how the scale of turbulence, the displacement between...

  11. Spectral geometry of spacetime

    CERN Document Server

    Kopf, T

    2000-01-01

    Spacetime, understood as a globally hyperbolic manifold, may be characterized by spectral data using a 3+1 splitting into space and time, a description of space by spectral triples and by employing causal relationships, as proposed earlier. Here, it is proposed to use the Hadamard condition of quantum field theory as a smoothness principle.

  12. Hydrocarbon Spectral Database

    Science.gov (United States)

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  13. Libraries Today, Libraries Tomorrow: Contemporary Library Practices and the Role of Library Space in the L

    Directory of Open Access Journals (Sweden)

    Ana Vogrinčič Čepič

    2013-09-01

    Full Text Available ABSTRACTPurpose: The article uses sociological concepts in order to rethink the changes in library practices. Contemporary trends are discussed with regard to the changing nature of working habits, referring mostly to the new technology, and the (emergence of the third space phenomenon. The author does not regard libraries only as concrete public service institutions, but rather as complex cultural forms, taking in consideration wider social context with a stress on users’ practices in relation to space.Methodology/approach: The article is based on the (self- observation of the public library use, and on the (discourse analysis of internal library documents (i.e. annual reports and plans and secondary sociological literature. As such, the cultural form approach represents a classic method of sociology of culture.Results: The study of relevant material in combination with direct personal experiences reveals socio-structural causes for the change of users’ needs and habits, and points at the difficulty of spatial redefinition of libraries as well as at the power of the discourse.Research limitations: The article is limited to an observation of users’ practices in some of the public libraries in Ljubljana and examines only a small number of annual reports – the discoveries are then further debated from the sociological perspective.Originality/practical implications: The article offers sociological insight in the current issues of the library science and tries to suggest a wider explanation that could answer some of the challenges of the contemporary librarianship.

  14. Spectral Geometry and Causality

    CERN Document Server

    Kopf, T

    1996-01-01

    For a physical interpretation of a theory of quantum gravity, it is necessary to recover classical spacetime, at least approximately. However, quantum gravity may eventually provide classical spacetimes by giving spectral data similar to those appearing in noncommutative geometry, rather than by giving directly a spacetime manifold. It is shown that a globally hyperbolic Lorentzian manifold can be given by spectral data. A new phenomenon in the context of spectral geometry is observed: causal relationships. The employment of the causal relationships of spectral data is shown to lead to a highly efficient description of Lorentzian manifolds, indicating the possible usefulness of this approach. Connections to free quantum field theory are discussed for both motivation and physical interpretation. It is conjectured that the necessary spectral data can be generically obtained from an effective field theory having the fundamental structures of generalized quantum mechanics: a decoherence functional and a choice of...

  15. MRM screening/biomarker discovery with linear ion trap MS: a library of human cancer-specific peptides

    Directory of Open Access Journals (Sweden)

    Lazar Iulia M

    2009-03-01

    Full Text Available Abstract Background The discovery of novel protein biomarkers is essential in the clinical setting to enable early disease diagnosis and increase survivability rates. To facilitate differential expression analysis and biomarker discovery, a variety of tandem mass spectrometry (MS/MS-based protein profiling techniques have been developed. For achieving sensitive detection and accurate quantitation, targeted MS screening approaches, such as multiple reaction monitoring (MRM, have been implemented. Methods MCF-7 breast cancer protein cellular extracts were analyzed by 2D-strong cation exchange (SCX/reversed phase liquid chromatography (RPLC separations interfaced to linear ion trap MS detection. MS data were interpreted with the Sequest-based Bioworks software (Thermo Electron. In-house developed Perl-scripts were used to calculate the spectral counts and the representative fragment ions for each peptide. Results In this work, we report on the generation of a library of 9,677 peptides (p a, b, y ions in the spectrum, the retention time, and the top 10 most intense product ions that correspond to a given peptide. Only proteins identified by at least two spectral counts are listed. The experimental distribution of protein frequencies, as a function of molecular weight, closely matched the theoretical distribution of proteins in the human proteome, as provided in the SwissProt database. The amino acid sequence coverage of the identified proteins ranged from 0.04% to 98.3%. The highest-abundance proteins in the cellular extract had a molecular weight (MW Conclusion Preliminary experiments have demonstrated that putative biomarkers, that are not detectable by conventional data dependent MS acquisition methods in complex un-fractionated samples, can be reliable identified with the information provided in this library. Based on the spectral count, the quality of a tandem mass spectrum and the m/z values for a parent peptide and its most abundant daughter

  16. Snapshot spectral imaging system

    Science.gov (United States)

    Arnold, Thomas; De Biasio, Martin; McGunnigle, Gerald; Leitner, Raimund

    2010-02-01

    Spectral imaging is the combination of spectroscopy and imaging. These fields are well developed and are used intensively in many application fields including industry and the life sciences. The classical approach to acquire hyper-spectral data is to sequentially scan a sample in space or wavelength. These acquisition methods are time consuming because only two spatial dimensions, or one spatial and the spectral dimension, can be acquired simultaneously. With a computed tomography imaging spectrometer (CTIS) it is possible to acquire two spatial dimensions and a spectral dimension during a single integration time, without scanning either spatial or spectral dimensions. This makes it possible to acquire dynamic image scenes without spatial registration of the hyperspectral data. This is advantageous compared to tunable filter based systems which need sophisticated image registration techniques. While tunable filters provide full spatial and spectral resolution, for CTIS systems there is always a tradeoff between spatial and spectral resolution as the spatial and spectral information corresponding to an image cube is squeezed onto a 2D image. The presented CTIS system uses a spectral-dispersion element to project the spectral and spatial image information onto a 2D CCD camera array. The system presented in this paper is designed for a microscopy application for the analysis of fixed specimens in pathology and cytogenetics, cell imaging and material analysis. However, the CTIS approach is not limited to microscopy applications, thus it would be possible to implement it in a hand-held device for e.g. real-time, intra-surgery tissue classification.

  17. Marketing the hospital library.

    Science.gov (United States)

    Bridges, Jane

    2005-01-01

    Many librarians do not see themselves as marketers, but marketing is an essential role for hospital librarians. Library work involves education, and there are parallels between marketing and education as described in this article. It is incumbent upon hospital librarians actively to pursue ways of reminding their customers about library services. This article reinforces the idea that marketing is an element in many of the things that librarians already do, and includes a list of suggested marketing strategies intended to remind administrators, physicians, and other customers that they have libraries in their organizations.

  18. A tool for manual endmember selection and spectral unmixing

    Science.gov (United States)

    Bateson, C. Ann; Curtiss, Brian

    1993-01-01

    Sampling a continuous radiance spectrum in many narrow contiguous spectral bands results in a high covariance between the bands. Hence, the true dimensionality of imaging spectrometer data is not determined by the number of spectral bands, but by the number of spectrally unique signatures whose mixtures reproduce the spectral variance observed in an image. Methods to unmix high dimensional multispectral data use principal components analysis to reduce the dimensionality. The variance of the spectral data is modeled as a linear combination of a finite set of endmembers in the space of the eigen-vectors that account for most of the variance. The number and characteristics of these endmembers are determined not only by the number and characteristics of the spectrally unique materials on the surface but also by processes (e.g., illumination, atmospheric scattering and absorption) affecting the signal received by the sensor. Selection of endmember spectra has typically been from a library. However, since most libraries are incomplete and do not account for the processes mentioned above, we have devised a computer display that allows researchers to explore interactively the eigenvector space of a representative and mean-corrected subset of the image data in search of extreme spectra to designate as endmembers. This display, which is based on parallel coordinates, is unique in the area of multidimensional visualization in that it includes not only a passive view of higher dimensional data but also the capability to interact and move geometrical objects in higher dimensional spaces.

  19. SCHOOL COMMUNITY PERCEPTION OF LIBRARY APPS AGAINTS LIBRARY EMPOWERMENT

    Directory of Open Access Journals (Sweden)

    Achmad Riyadi Alberto

    2017-07-01

    Full Text Available Abstract. This research is motivated by the development of information and communication technology (ICT in the library world so rapidly that allows libraries in the present to develop its services into digital-based services. This study aims to find out the school community’s perception of library apps developed by Riche Cynthia Johan, Hana Silvana, and Holin Sulistyo and its influence on library empowerment at the library of SD Laboratorium Percontohan UPI Bandung. Library apps in this research belong to the context of m-libraries, which is a library that meets the needs of its users by using mobile platforms such as smartphones,computers, and other mobile devices. Empowerment of library is the utilization of all aspects of the implementation of libraries to the best in order to achieve the expected goals. An analysis of the schoolcommunity’s perception of library apps using the Technology Acceptance Model (TAM includes: ease of use, usefulness, usability, usage trends, and real-use conditions. While the empowerment of the library includes aspects: information empowerment, empowerment of learning resources, empowerment of human resources, empowerment of library facilities, and library promotion. The research method used in this research is descriptive method with quantitative approach. Population and sample in this research is school community at SD Laboratorium Percontohan UPI Bandung. Determination of sample criteria by using disproportionate stratified random sampling with the number of samples of 83 respondents. Data analysis using simple linear regression to measure the influence of school community perception about library apps to library empowerment. The result of data analysis shows that there is influence between school community perception about library apps to library empowerment at library of SD Laboratorium Percontohan UPI Bandung which is proved by library acceptance level and library empowerment improvement.

  20. Croatian library leaders’ views on (their library quality

    Directory of Open Access Journals (Sweden)

    Kornelija Petr Balog

    2014-04-01

    Full Text Available The purpose of this paper is to determine and describe the library culture in Croatian public libraries. Semi-structured interviews with 14 library directors (ten public and four academic were conducted. The tentative discussion topics were: definition of quality, responsibility for quality, satisfaction with library services, familiarization with user perspective of library and librarians, monitoring of user expectations and opinions. These interviews incorporate some of the findings of the project Evaluation of library and information services: public and academic libraries. The project investigates library culture in Croatian public and academic libraries and their preparedness for activities of performance measurement. The interviews reveal that library culture has changed positively in the past few years and that library leaders have positive attitude towards quality and evaluation activities. Library culture in Croatian libraries is a relatively new concept and as such was not actively developed and/or created. This article looks into the library culture of Croatian libraries, but at the same time investigates whether there is any trace of culture of assessment in them. Also, this article brings the latest update on views, opinions and atmosphere in Croatian public and academic libraries.

  1. Library Automation Software Packages used in Academic Libraries of Nepal

    OpenAIRE

    Sharma (Baral), Sabitri

    2007-01-01

    This thesis presents a comparative assessment of the library automation software packages used in Nepalese academic libraries. It focuses on the evaluation of software on the basis of certain important checkpoints. It also highlights the importance of library automation, library activities and services.

  2. Integrated Library Information Systems in ARL Libraries. SPEC Kit 90.

    Science.gov (United States)

    Hirshon, Arnold

    Based on an October 1982 survey of 31 selected members of the Association of Research Libraries (ARL), this report presents library planning documents, general system descriptions and reviews, and examples of library specifications--all dealing with integrated library information systems (ILIS). An ILIS is defined as a fully interactive integrated…

  3. 2010 Library of the Year: Columbus Metropolitan Library

    Science.gov (United States)

    Berry, John N., III

    2010-01-01

    This article features Columbus Metropolitan Library (CML), winner of the Gale/"Library Journal" Library of the Year Award 2010. CML, comprised of an operations center and 21 branches, serves the 847,376 people who inhabit a large portion of Franklin County in central Ohio. It is an independent library with its own taxing district. CML…

  4. Genomic libraries: I. Construction and screening of fosmid genomic libraries.

    Science.gov (United States)

    Quail, Mike A; Matthews, Lucy; Sims, Sarah; Lloyd, Christine; Beasley, Helen; Baxter, Simon W

    2011-01-01

    Large insert genome libraries have been a core resource required to sequence genomes, analyze haplotypes, and aid gene discovery. While next generation sequencing technologies are revolutionizing the field of genomics, traditional genome libraries will still be required for accurate genome assembly. Their utility is also being extended to functional studies for understanding DNA regulatory elements. Here, we present a detailed method for constructing genomic fosmid libraries, testing for common contaminants, gridding the library to nylon membranes, then hybridizing the library membranes with a radiolabeled probe to identify corresponding genomic clones. While this chapter focuses on fosmid libraries, many of these steps can also be applied to bacterial artificial chromosome libraries.

  5. A Real-Time Infrared Ultra-Spectral Signature Classification Method via Spatial Pyramid Matching.

    Science.gov (United States)

    Mei, Xiaoguang; Ma, Yong; Li, Chang; Fan, Fan; Huang, Jun; Ma, Jiayi

    2015-07-03

    The state-of-the-art ultra-spectral sensor technology brings new hope for high precision applications due to its high spectral resolution. However, it also comes with new challenges, such as the high data dimension and noise problems. In this paper, we propose a real-time method for infrared ultra-spectral signature classification via spatial pyramid matching (SPM), which includes two aspects. First, we introduce an infrared ultra-spectral signature similarity measure method via SPM, which is the foundation of the matching-based classification method. Second, we propose the classification method with reference spectral libraries, which utilizes the SPM-based similarity for the real-time infrared ultra-spectral signature classification with robustness performance. Specifically, instead of matching with each spectrum in the spectral library, our method is based on feature matching, which includes a feature library-generating phase. We calculate the SPM-based similarity between the feature of the spectrum and that of each spectrum of the reference feature library, then take the class index of the corresponding spectrum having the maximum similarity as the final result. Experimental comparisons on two publicly-available datasets demonstrate that the proposed method effectively improves the real-time classification performance and robustness to noise.

  6. A Real-Time Infrared Ultra-Spectral Signature Classification Method via Spatial Pyramid Matching

    Directory of Open Access Journals (Sweden)

    Xiaoguang Mei

    2015-07-01

    Full Text Available The state-of-the-art ultra-spectral sensor technology brings new hope for high precision applications due to its high spectral resolution. However, it also comes with new challenges, such as the high data dimension and noise problems. In this paper, we propose a real-time method for infrared ultra-spectral signature classification via spatial pyramid matching (SPM, which includes two aspects. First, we introduce an infrared ultra-spectral signature similarity measure method via SPM, which is the foundation of the matching-based classification method. Second, we propose the classification method with reference spectral libraries, which utilizes the SPM-based similarity for the real-time infrared ultra-spectral signature classification with robustness performance. Specifically, instead of matching with each spectrum in the spectral library, our method is based on feature matching, which includes a feature library-generating phase. We calculate the SPM-based similarity between the feature of the spectrum and that of each spectrum of the reference feature library, then take the class index of the corresponding spectrum having the maximum similarity as the final result. Experimental comparisons on two publicly-available datasets demonstrate that the proposed method effectively improves the real-time classification performance and robustness to noise.

  7. Libraries in Colorado: MedlinePlus

    Science.gov (United States)

    ... LibraryLibraries in Colorado URL of this page: https://medlineplus.gov/libraries/colorado.html Libraries in Colorado ... Room 2106C Aurora, CO 80045 303-724-2111 http://hslibrary.ucdenver.edu/ Denver National Jewish Health Library ...

  8. USGS Photographic Library

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The U.S. Geological Survey Denver Library maintains a collection of over 400,000 photographs taken during geologic studies of the United States and its territories...

  9. Archives Library Information Center

    Data.gov (United States)

    National Archives and Records Administration — ALIC is an online library catalog of books, periodicals, and other materials contained in Archives I and II and book collections located in other facilities.

  10. Working in the Library

    CERN Multimedia

    Maximilien Brice

    2009-01-01

    Head Librarian Jens Vigen seeking information on the first discussions concerning the construction of the Large Hadron Collider in the LEP Tunnel (1984), here assisted by two of the library apprentices, Barbara Veyre and Dina-Elisabeth Bimbu (seated).

  11. Las Campanas Stellar Library

    Science.gov (United States)

    Chilingarian, Igor; Zolotukhin, Ivan; Beletsky, Yuri; Worthey, Guy

    2015-08-01

    Stellar libraries are fundamental tools required to understand stellar populations in star clusters and galaxies as well as properties of individual stars. Comprehensive libraries exist in the optical domain, but the near-infrared (NIR) domain stays a couple of decades behind. Here we present the Las Campanas Stellar Library project aiming at obtaining high signal-to-noise intermediate-resolution (R=8000) NIR spectra (0.83libraries, INDO-US and UVES-POP and followed up about 400 non-variable stars in the NIR in order to get complete optical-NIR coverage. Worth mentioning that our current sample includes about 80 AGB stars and a few dozens of bulge/LMC/SMC stars.

  12. Web design for libraries

    CERN Document Server

    Rubenstein, Charles

    2014-01-01

    Having a clear, attractive, and easy-to-navigate website that allows users to quickly find what they want is essential for any organization-including a library. This workbook makes website creation easy-no HTML required.

  13. Presidential Electronic Records Library

    Data.gov (United States)

    National Archives and Records Administration — PERL (Presidential Electronic Records Library) used to ingest and provide internal access to the Presidential electronic Records of the Reagan, Bush, and Clinton...

  14. Library Architecture: Some Observations

    Directory of Open Access Journals (Sweden)

    Bernhard Fabian

    2002-07-01

    Full Text Available There are plenty of libraries (among them many university and research libraries which do not provide adequate work-places. Chairs may have been selected for their stylish look rather than for their physical comfort. Desk lamps may have been deemed unnecessary (they might have distorted the overall impression which the reading room was expected to make And so on. I keep wondering how many librarians have spent some time in their libraries as readers, and have assessed their reading rooms from the user’s point of view. Have they been in a cubicle? Or have they read a book under glaring neon lights? Do they know how well their air-conditioning works? I know a library in which the only window that can be opened is in the librarian’s office.

  15. Mold Image Library

    Science.gov (United States)

    The image library contains mold-related images in seven categories. There are also animated images that you can choose to view and download. These photos may be used for presentations and educational purposes without contacting EPA.

  16. Iowa DNR - NRGIS Library

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The Natural Resources Geographic Information System (NRGIS) Library is a Geographic Information System (GIS) repository developed and maintained by the GIS Section...

  17. Increasing Public Library Productivity.

    Science.gov (United States)

    Samuelson, Howard

    1981-01-01

    Suggests ways of improving productivity for public libraries faced with increased accountability, dwindling revenues, and continuing inflation. Techniques described include work simplification, work analysis, improved management, and employee motivation. (RAA)

  18. The Gosford Toy Library.

    Science.gov (United States)

    Fisher, Heather

    1995-01-01

    Describes the development of a toy library in Gosford (Australia). Discusses community support, state and local funding and expenditures, planning loan procedures, the catalog, presentation and storage, classification, the official opening, and staff support and community reaction. (AEF)

  19. Library Management Systems

    Directory of Open Access Journals (Sweden)

    Ionel Enache

    2012-01-01

    Full Text Available Today’s libraries are faced with the innumerable challenges posed by an information universe on rapid expansion. The increasing expectations and the users’ needs to access faster and easier the relevant information is in a constant relation to the institutional demand for the increasing of operational efficiency. The library integrated systems enable all types of libraries with accessible instruments and the necessary assistance needed in the working flow in order to cope with personal and institutional demands both in present and in future times. The integrated system can be configured in order to meet every type of library policy or procedure thus allowing the creation of a sole working flow.

  20. Controlling hospital library theft.

    Science.gov (United States)

    Cuddy, Theresa M; Marchok, Catherine

    2003-04-01

    At Capital Health System/Fuld Campus (formerly Helene Fuld Medical Center), the Health Sciences Library lost many books and videocassettes. These materials were listed in the catalog but were missing when staff went to the shelves. The hospital had experienced a downsizing of staff, a reorganization, and a merger. When the library staff did an inventory, $10,000 worth of materials were found to be missing. We corrected the situation through a series of steps that we believe will help other libraries control their theft. Through regularly scheduling inventories, monitoring items, advertising, and using specific security measures, we have successfully controlled the library theft. The January 2002 inventory resulted in meeting our goal of zero missing books and videocassettes. We work to maintain that goal.