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Data

Distribution by Scientific Domains
Medical Sciences36%
Life Sciences18%
Chemistry11%
Business, Economics, Finance and Accounting5%
Earth and Environmental Science5%
Humanities and Social Sciences5%
Engineering4%
Mathematics and Statistics3%
Psychology2%
5 Other Domains11%

Kinds of Data

  • absence data
  • absorption data
  • absorption spectroscopy data
  • abundance data
  • accident data
  • accounting data
  • accumulated data
  • accumulating data
  • accurate data
  • accurate mass data
  • acid sequence data
  • acquired data
  • activity data
  • actual data
  • additional data
  • adequate data
  • adherence data
  • administrative claim data
  • administrative data
  • admission data
  • adsorption data
  • adult data
  • aflp data
  • age data
  • aggregate data
  • air data
  • allele frequency data
  • allozyme data
  • american data
  • analogous data
  • analysing data
  • analysis data
  • analytical data
  • analyzing data
  • anamnestic data
  • anatomical data
  • ancillary data
  • anecdotal data
  • angiographic data
  • angle data
  • animal data
  • annual data
  • anomalous dispersion data
  • anthropometric data
  • application data
  • appropriate data
  • archaeological data
  • archival data
  • area data
  • areal data
  • array data
  • article present data
  • assessment data
  • association data
  • atlas data
  • atomic data
  • atomic resolution data
  • auction data
  • audit data
  • australian data
  • available clinical data
  • available data
  • available experimental data
  • available literature data
  • available published data
  • background data
  • band data
  • baseline data
  • basic data
  • basic demographic data
  • behavioral data
  • behavioural data
  • benchmark data
  • best available data
  • best data
  • billing data
  • binary data
  • binding data
  • bioassay data
  • biochemical data
  • biodiversity data
  • biological data
  • biomarker data
  • biomass data
  • biometric data
  • biophysical data
  • biostratigraphic data
  • birth certificate data
  • birth data
  • bmd data
  • bold data
  • borehole data
  • boundary data
  • breast cancer data
  • british data
  • c data
  • calculated data
  • calibration data
  • calorimetric data
  • calorimetry data
  • canadian data
  • cancer data
  • cancer incidence data
  • cancer registry data
  • capture data
  • care data
  • case study data
  • case-control data
  • catch data
  • categorical data
  • cauchy data
  • cd data
  • censored data
  • census data
  • certificate data
  • characteristic data
  • characterization data
  • chemical data
  • chemistry data
  • chromatographic data
  • claim data
  • climate data
  • climatic data
  • clinical data
  • clinical pharmacokinetic data
  • clinical trial data
  • clinical trials data
  • clinicopathologic data
  • clinicopathological data
  • clustered data
  • co-occurrence data
  • cognitive data
  • cohort data
  • collected data
  • collecting data
  • combined data
  • combining data
  • community data
  • comparable data
  • comparative data
  • comparing data
  • comparison data
  • compensation data
  • complementary data
  • complete data
  • complex data
  • composition data
  • compositional data
  • comprehensive data
  • concentration data
  • conductivity data
  • conflicting data
  • considerable data
  • consistent data
  • consumption data
  • contemporary data
  • content data
  • continuous data
  • control data
  • controlled data
  • controversial data
  • conventional data
  • convincing data
  • coordinate data
  • core data
  • correlated data
  • correlational data
  • corresponding data
  • corresponding experimental data
  • cost data
  • count data
  • country-level data
  • county-level data
  • course data
  • covariance data
  • covariate data
  • cover data
  • crash data
  • crime data
  • cross-country data
  • cross-section data
  • cross-sectional data
  • cross-sectional survey data
  • crystal data
  • crystal structural data
  • crystallization data
  • crystallographic data
  • ct data
  • culture data
  • cumulative data
  • current data
  • current population survey data
  • cytogenetic data
  • cytometry data
  • cytotoxicity data
  • daily data
  • daily rainfall data
  • dce-mri data
  • death data
  • deformation data
  • degradation data
  • demand data
  • demographic data
  • density data
  • dental data
  • dependent data
  • depth data
  • descriptive data
  • design data
  • detailed data
  • developmental data
  • diagnostic data
  • diary data
  • dichotomous data
  • dietary data
  • different data
  • diffraction data
  • diffusion data
  • digital data
  • direct data
  • discrete data
  • dispensing data
  • dispersion data
  • displacement data
  • distributed data
  • distribution data
  • distributional data
  • dna data
  • dna sequence data
  • donor data
  • dsc data
  • dti data
  • dynamic data
  • earthquake data
  • ecg data
  • echocardiographic data
  • ecological data
  • economic data
  • eddy covariance data
  • eeg data
  • effect data
  • efficacy data
  • effort data
  • electrochemical data
  • electron diffraction data
  • electron microscopy data
  • electronic data
  • electrophysiologic data
  • electrophysiological data
  • element data
  • elevation data
  • emerging data
  • emg data
    		•
  • emission data
  • empirical data
  • employee data
  • employment data
  • encounter data
  • endocrine data
  • environmental data
  • epidemiologic data
  • epidemiological data
  • epr data
  • epsi data
  • equilibrium data
  • erp data
  • ethnicity data
  • ethnographic data
  • eurobarometer data
  • european data
  • evaluable data
  • evaluation data
  • event data
  • examination data
  • examiner data
  • exchange data
  • exchange rate data
  • excretion data
  • existing data
  • expenditure data
  • experiment data
  • experimental data
  • exposure data
  • expression data
  • extensive data
  • external data
  • extracted data
  • extraction data
  • failure data
  • failure time data
  • familial data
  • family data
  • family history data
  • far-field data
  • fatigue data
  • field data
  • field survey data
  • file data
  • financial data
  • finnish data
  • firm-level data
  • first data
  • fish community data
  • fisheries data
  • fission-track data
  • floristic data
  • flow data
  • fluctuation data
  • fluid inclusion data
  • fluorescence data
  • flux data
  • fmri data
  • focal data
  • focus group data
  • follow-up data
  • force survey data
  • fossil data
  • fossil pollen data
  • fracture data
  • fragment length polymorphism data
  • fragmentation data
  • frequency data
  • function data
  • functional data
  • fundamental data
  • gas data
  • gauge data
  • gene expression data
  • gene sequence data
  • generated data
  • genetic data
  • genome data
  • genome sequence data
  • genomic data
  • genomic sequence data
  • genotype data
  • genotypic data
  • genotyping data
  • geochemical data
  • geochronological data
  • geographical data
  • geological data
  • geometric morphometric data
  • geomorphological data
  • geophysical data
  • german data
  • gis data
  • global data
  • good data
  • gpr data
  • gps data
  • gravity data
  • ground truth data
  • group data
  • growth data
  • habitat data
  • haplotype data
  • hapmap data
  • head data
  • health data
  • health survey data
  • healthcare data
  • height data
  • hemodynamic data
  • heterogeneous data
  • high frequency data
  • high quality data
  • high-dimensional data
  • high-frequency data
  • high-quality data
  • high-resolution data
  • histological data
  • histology data
  • histopathologic data
  • histopathological data
  • historic data
  • historical data
  • historical process data
  • history data
  • hospital data
  • hospitalisation data
  • hospitalization data
  • household data
  • household survey data
  • human data
  • hydraulic head data
  • hydrologic data
  • hydrological data
  • i data
  • i used data
  • identification data
  • image data
  • imaging data
  • immunological data
  • import data
  • important data
  • in-house data
  • inactivation data
  • incidence data
  • included data
  • inclusion data
  • incomplete data
  • independent data
  • index data
  • individual data
  • individual patient data
  • individual-level data
  • industrial data
  • industry data
  • industry-level data
  • infection data
  • infrared data
  • inhibition data
  • initial data
  • input data
  • instrumental data
  • insufficient data
  • insurance claim data
  • intake data
  • intensity data
  • interaction data
  • internal data
  • international data
  • interval data
  • interval-censored data
  • intervention data
  • interview data
  • intra-day data
  • intraday data
  • inventory data
  • ion data
  • ir data
  • isotherm data
  • isotope data
  • isotopic data
  • k-space data
  • key data
  • kinematic data
  • kinetic data
  • kinetics data
  • laboratory data
  • laboratory powder diffraction data
  • laboratory x-ray powder diffraction data
  • labour force survey data
  • land cover data
  • land use data
  • land-cover data
  • landmark data
  • latest data
  • length data
  • length polymorphism data
  • level data
  • lidar data
  • life data
  • life history data
  • life-history data
  • lifetime data
  • limited data
  • limited experimental data
  • line data
  • linguistic data
  • liquid equilibrium data
  • literature data
  • little data
  • load data
  • local data
  • location data
  • log data
  • logging data
  • long-term data
  • long-term demographic data
  • long-term follow-up data
  • long-term survival data
  • longitudinal binary data
  • longitudinal categorical data
  • longitudinal data
  • low-resolution data
  • macroeconomic data
  • macroinvertebrate data
  • mad data
  • magnetic data
  • magnetic resonance data
  • magnetic resonance imaging data
  • magnetic susceptibility data
  • management data
  • manufacturing data
  • map data
  • mapping data
  • mark-recapture data
  • marker data
  • market data
  • mass data
  • mass spectral data
  • mass spectrometric data
  • mass spectrometry data
  • material data
  • mean data
  • meaningful data
  • measure data
  • measured data
  • measurement data
  • mechanical data
  • mechanistic data
  • medical data
  • medical examiner data
  • medical history data
    		•
  • medical record data
  • medicare claim data
  • medicare data
  • medication data
  • metabolism data
  • metabolite data
  • meteorological data
  • methods data
  • metric data
  • micro data
  • microarray data
  • microarray expression data
  • microbiological data
  • microsatellite data
  • microscopy data
  • microstructural data
  • minimal data
  • miss data
  • mitochondrial data
  • mitochondrial dna data
  • mitochondrial dna sequence data
  • mitochondrial sequence data
  • model data
  • modelling data
  • modern data
  • moisture data
  • molecular data
  • molecular genetic data
  • molecular marker data
  • molecular sequence data
  • monitoring data
  • morbidity data
  • morphological data
  • morphometric data
  • mortality data
  • motion capture data
  • movement data
  • mr data
  • mri data
  • mrs data
  • mrsi data
  • msn data
  • mtdna data
  • mtdna sequence data
  • multi-proxy data
  • multichannel data
  • multivariate data
  • mutagenesi data
  • mutation data
  • mössbauer data
  • narrative data
  • national data
  • national survey data
  • nationwide data
  • native data
  • native diffraction data
  • necessary data
  • neonatal data
  • network data
  • neuroimaging data
  • neutron data
  • neutron diffraction data
  • neutron powder diffraction data
  • new data
  • new field data
  • nir data
  • nmr data
  • nmr spectral data
  • nmr spectroscopic data
  • noe data
  • noisy data
  • normal data
  • normative data
  • novel data
  • numerical data
  • objective data
  • observation data
  • observational data
  • observed data
  • obstetric data
  • obtained data
  • occupational data
  • occurrence data
  • of data
  • only data
  • only limited data
  • only sparse data
  • operating data
  • operational data
  • operative data
  • opinion data
  • optical data
  • option data
  • ordinal data
  • original data
  • original survey data
  • other data
  • other published data
  • our data
  • outcome data
  • output data
  • own data
  • own experimental data
  • paired data
  • palaeoecological data
  • palaeomagnetic data
  • palaeontological data
  • panel data
  • paper present data
  • participant data
  • past data
  • patch test data
  • patent data
  • pathologic data
  • pathological data
  • pathology data
  • patient data
  • patient demographic data
  • patient-level data
  • pedigree data
  • performance data
  • perfusion data
  • perinatal data
  • periodontal data
  • perioperative data
  • permanent plot data
  • personal data
  • petrographic data
  • petrophysical data
  • ph data
  • pharmacodynamic data
  • pharmacokinetic data
  • pharmacological data
  • pharmacy data
  • pharmacy dispensing data
  • phase data
  • phenotypic data
  • photometric data
  • phylogenetic data
  • phylogeographic data
  • physicochemical data
  • physiologic data
  • physiological data
  • pilot data
  • pk data
  • plant data
  • plot data
  • point data
  • polarization data
  • poll data
  • pollen data
  • polymorphism data
  • polysomnographic data
  • pooled data
  • poor data
  • population data
  • population genetic data
  • population survey data
  • postoperative data
  • potential data
  • powder data
  • powder diffraction data
  • practical data
  • pre-clinical data
  • precipitation data
  • preclinical data
  • preference data
  • preliminary crystallographic data
  • preliminary data
  • preliminary x-ray diffraction data
  • preoperative data
  • prescribing data
  • prescription data
  • presence-only data
  • present data
  • presented data
  • pressure data
  • pretreatment data
  • prevalence data
  • previous data
  • previous experimental data
  • price data
  • primary data
  • prior data
  • process data
  • product data
  • production data
  • profile data
  • profiling data
  • program data
  • promising data
  • prospective data
  • protein expression data
  • proteomic data
  • proxy data
  • psychological data
  • psychometric data
  • published data
  • published experimental data
  • pvt data
  • qol data
  • qualitative data
  • qualitative interview data
  • quality data
  • quantitative data
  • quarterly data
  • questionnaire data
  • radar data
  • radial velocity data
  • radiance data
  • radiographic data
  • radiologic data
  • radiological data
  • radiosonde data
  • rain gauge data
  • rainfall data
  • raman data
  • rapd data
  • rate data
  • raw data
  • rdna data
  • rdna sequence data
  • re-analysi data
  • reaction data
  • real data
  • real-time data
  • real-world data
  • realistic data
  • reanalysi data
  • recent clinical data
  • recent data
  • recent experimental data
  • record data
  • recorded data
  • recovery data
  • redundant data
  • reference data
  • reflection data
  • reflectivity data
  • regional data
  • register data
  • registered data
  • registration data
  • registry data
  • relational data
  • relaxation data
  • relevant data
  • reliability data
  • reliable data
  • remote data
  • remote sensing data
  • remote-sensing data
  • report data
    		•
  • reported data
  • reporting data
  • representative data
  • reproducible data
  • reproductive data
  • research data
  • residue data
  • resistance data
  • resolution data
  • resonance data
  • resonance imaging data
  • resource utilization data
  • response data
  • result complete data
  • result data
  • resulting data
  • retention data
  • retrospective data
  • return data
  • review data
  • rheological data
  • rich data
  • richness data
  • risk data
  • routine data
  • rt-pcr data
  • runoff data
  • sad data
  • safety data
  • sales data
  • same data
  • sample data
  • sample survey data
  • sampling data
  • satellite data
  • sax data
  • scale data
  • scanner data
  • scant data
  • scarce data
  • scattering data
  • science data
  • scientific data
  • screening data
  • secondary data
  • sedimentological data
  • seer data
  • segregation data
  • seismic data
  • seismic reflection data
  • self-potential data
  • self-report data
  • self-reported data
  • sensed data
  • sensing data
  • sensor data
  • sensory data
  • sequence data
  • sequencing data
  • sequential data
  • series data
  • serological data
  • several data
  • severity data
  • shape data
  • sighting data
  • similar data
  • simulated data
  • simulation data
  • single-crystal data
  • single-crystal diffraction data
  • single-crystal x-ray diffraction data
  • site-specific data
  • situ data
  • size data
  • smoking data
  • snp data
  • social science data
  • socio-demographic data
  • sociodemographic data
  • socioeconomic data
  • soil data
  • soil moisture data
  • solubility data
  • sounding data
  • source data
  • space data
  • space-time data
  • sparse data
  • spatial data
  • spatiotemporal data
  • species absence data
  • species abundance data
  • species data
  • species distribution data
  • species occurrence data
  • specific data
  • spectral data
  • spectrometric data
  • spectrometry data
  • spectrophotometric data
  • spectroscopic data
  • spectroscopy data
  • spectrum data
  • speed data
  • spirometry data
  • sst data
  • stability data
  • stable isotope data
  • staging data
  • state data
  • static data
  • station data
  • statistical data
  • statistics data
  • stock market data
  • strain data
  • stratigraphic data
  • streamflow data
  • strength data
  • stress data
  • structural data
  • structure data
  • studies data
  • study data
  • study used data
  • subjective data
  • sufficient data
  • summary data
  • supplementary data
  • supporting data
  • supportive data
  • surface data
  • surveillance data
  • survey data
  • survival data
  • susceptibility data
  • swedish data
  • symptom data
  • synchrotron data
  • synchrotron diffraction data
  • synchrotron powder diffraction data
  • synchrotron x-ray diffraction data
  • synchrotron x-ray powder diffraction data
  • synthetic data
  • system data
  • systematic data
  • tag data
  • tagging data
  • technical data
  • telemetry data
  • temperature data
  • temporal data
  • terrain data
  • test data
  • testing data
  • text data
  • textual data
  • theoretical data
  • therapeutic data
  • thermal analysis data
  • thermal data
  • thermodynamic data
  • these data
  • three-dimensional data
  • time course data
  • time data
  • time series data
  • time-sery data
  • time-to-event data
  • titration data
  • tomography data
  • toxicity data
  • toxicological data
  • trace element data
  • track data
  • trade data
  • traffic data
  • training data
  • trait data
  • transaction data
  • transactions data
  • transition data
  • transport data
  • trap data
  • treatment data
  • treatment outcome data
  • trend data
  • triad data
  • trial data
  • trials data
  • truth data
  • tumor data
  • twin data
  • u.s. census data
  • u.s. data
  • uk data
  • ultrastructural data
  • underlying data
  • unique data
  • unit record data
  • unpublished data
  • uptake data
  • us data
  • usable data
  • usage data
  • use data
  • used data
  • useful data
  • utilization data
  • utilizing data
  • vaccination data
  • valid data
  • validation data
  • valuable data
  • variety of data
  • various data
  • vegetation data
  • velocity data
  • very little data
  • vibration data
  • video data
  • viscosity data
  • visit data
  • vitro data
  • vivo data
  • vla data
  • volume data
  • water data
  • water quality data
  • wave data
  • weather data
  • web data
  • weekly data
  • weight data
  • wind data
  • wind speed data
  • workers' compensation data
  • x-ray crystallographic data
  • x-ray data
  • x-ray diffraction data
  • x-ray intensity data
  • x-ray powder diffraction data
  • x-ray scattering data
  • xp data
  • xrd data
  • year data
  • yield data
  • yielding data

    • Terms modified by Data

  • data abstraction
  • data access
  • data accuracy
  • data acquisition
  • data acquisition system
  • data acquisition time
  • data addressing
  • data aggregation
  • data alone
  • data analysis
  • data analysis method
  • data analysis methods
  • data analysis procedure
  • data analysis software
  • data analysis techniques
  • data analysis tool
  • data application
  • data approach
  • data archives
  • data argue
  • data assimilation
  • data assimilation scheme
  • data assimilation system
  • data augmentation
  • data availability
  • data available
  • data bank
  • data base
  • data base search
  • data being
  • data best
  • data better
  • data capture
  • data center
  • data classification
  • data collection
  • data collection form
  • data collection instrument
  • data collection method
  • data collection methods
  • data collection period
  • data collection process
  • data collection system
  • data collection techniques
  • data collection tool
  • data come
  • data communication
  • data comparing
  • data comparison
    		•
  • data compression
  • data consistent
  • data consisting
  • data corresponding
  • data coverage
  • data demonstrating
  • data density
  • data distribution
  • data element
  • data entry
  • data envelopment analysis
  • data envelopment analysis approach
  • data evaluation
  • data example
  • data extraction
  • data extraction form
  • data extraction tool
  • data feature
  • data field
  • data file
  • data fit
  • data fitting
  • data flow
  • data for children
  • data form
  • data format
  • data formats
  • data fusion
  • data gap
  • data gathering
  • data generation
  • data help
  • data highlight
  • data indicating
  • data infrastructure
  • data integration
  • data integrity
  • data interpretation
  • data inversion
  • data issues
  • data item
  • data layer
  • data lead
  • data limitation
  • data linkage
  • data loss
  • data make
  • data management
  • data matrix
    		•
  • data mechanism
  • data methodology
  • data mining
  • data mining techniques
  • data model
  • data modelling
  • data models
  • data monitoring
  • data necessary
  • data need
  • data network
  • data normalization
  • data only
  • data packet
  • data pair
  • data pattern
  • data permit
  • data pertaining
  • data point
  • data preparation
  • data problem
  • data processing
  • data products
  • data quality
  • data rate
  • data reconciliation
  • data reconstruction
  • data record
  • data recording
  • data reduction
  • data registry
  • data relating
  • data release
  • data relevant
  • data reporting
  • data repository
  • data requirement
  • data resolution
  • data resource
  • data retrieval
  • data reveal
  • data review
  • data sample
  • data sampling
  • data saturation
  • data segment
  • data selection
  • data series
  • data services
    		•
  • data set
  • data set available
  • data set consisting
  • data set containing
  • data set used
  • data setting
  • data sharing
  • data shed light
  • data sheet
  • data show
  • data showing
  • data shows
  • data simulation
  • data source
  • data source used
  • data sources.
  • data space
  • data specific
  • data storage
  • data stream
  • data structure
  • data study
  • data subject
  • data suggesting
  • data support
  • data synthesis
  • data system
  • data table
  • data techniques
  • data traffic
  • data transfer
  • data transformation
  • data transmission
  • data treatment
  • data type
  • data unit root test
  • data used
  • data useful
  • data user
  • data value
  • data variability
  • data variance
  • data verification
  • data very
  • data visualization
  • data volume

    • Selected Abstracts

    WHEN MISSING DATA ARE NOT MISSING: A NEW APPROACH TO EVALUATING SUPPLEMENTAL HOMICIDE REPORT IMPUTATION STRATEGIES,

    CRIMINOLOGY, Issue 4 2008
    TIM WADSWORTH
    The Supplemental Homicide Reports (SHR) are widely used in criminological research and inform a broad range of research topics and subsequent policy applications. A serious issue with the SHR is missing information about the offender and incident in many recorded homicides. Although it is convenient to discard cases with missing data before analysis, such discarding is not theoretically justified and can lead to incorrect substantive conclusions. Recently, several techniques for imputing missing SHR data have been proposed, but it is difficult to evaluate their effectiveness. This research presents a new approach to testing and evaluating SHR imputation techniques. Offender data that are missing in the SHR are often found in police records available for individual cities. We examine similarities and differences among cases with known offender characteristics in the SHR, cases with such information missing in the SHR but available in police records, and cases with such information missing in both sources. We then use these data sets to evaluate four different imputation techniques suggested in the literature (Fox, 2004; Messner, Deane, and Beaulieu, 2002; Pampel and Williams, 2000; Regoeczi and Riedel, 2003). We apply each imputation technique to the SHR, and for cases with information missing in the SHR but known in the police records, we see how well the imputed values correspond both with the individual known values and with the overall distributions in the police records. We discuss the outcome of our assessment of these strategies, and we outline important implications this assessment has for research using SHR data. [source]

    THE NARROWING GENDER GAP IN ARRESTS: ASSESSING COMPETING EXPLANATIONS USING SELF-REPORT, TRAFFIC FATALITY, AND OFFICIAL DATA ON DRUNK DRIVING, 1980,2004,

    CRIMINOLOGY, Issue 3 2008
    JENNIFER SCHWARTZ
    We evaluate two alternative explanations for the converging gender gap in arrest,changes in women's behavior versus changes in mechanisms of social control. Using the offense of drunk driving and three methodologically diverse data sets, we explore trends in the DUI gender gap. We probe for change across various age groups and across measures tapping DUI prevalence and chronicity. Augmented Dickey-Fuller time-series techniques are used to assess changes in the gender gap and levels of drunk driving from 1980 to 2004. Analyses show women of all ages making arrest gains on men,a converging gender gap. In contrast, self-report and traffic data indicate little or no systematic change in the DUI gender gap. Findings support the conclusion that mechanisms of social control have shifted to target female offending patterns disproportionately. Little support exists for the contention that increased strain and liberalized gender roles have altered the gender gap or female drunk-driving patterns. [source]

    COLLECT AND RELEASE DATA ON COERCIVE POLICE ACTIONS,

    CRIMINOLOGY AND PUBLIC POLICY, Issue 4 2007
    ROBERT J. KANE
    First page of article [source]

    THE CRIMINOGENIC EFFECTS OF IMPRISONMENT: EVIDENCE FROM STATE PANEL DATA, 1974,2002

    CRIMINOLOGY AND PUBLIC POLICY, Issue 3 2007
    LYNNE M. VIERAITIS
    Research Summary: The heavy reliance on the use of incarceration in an attempt to address the crime problem has resulted in a dramatic growth in the number of state prisoners over the past 30 years. In recent years, however, a growing concern has developed about the impact that large numbers of offenders released from prison will have on crime rates. Using a state panel data set for 46 states from 1974 to 2002, this study demonstrates that although prison population growth seems to be associated with statistically significant decreases in crime rates, increases in the number of prisoners released from prison seem to be significantly associated with increases in crime. Because we control for changes in prison population levels, we attribute the apparent positive influences on crime that seem to follow prison releases to the criminogenic effects of prison. Policy Implications: Policy makers should continue to serve the public interest by carefully considering policies that are designed to reduce incarceration rates and thus assuage the criminogenic effects of prison. These policies may include changes in sentencing, changes in probation and/or parole practices, or better funding of reentry services prerelease and postrelease. [source]

    Double-Blind, Randomized, Placebo-Controlled, Dose-Response Study of the Safety and Efficacy of Botulinum Toxin Type A in Subjects with Crow's Feet

    DERMATOLOGIC SURGERY, Issue 3 2005
    Nicholas J. Lowe MD
    Background Published evidence suggests that botulinum toxin type A (BTX-A) is an effective treatment for crow's feet. However, few dose-ranging studies have been performed. Objectives To assess the safety and efficacy of a single treatment with one of four doses of BTX-A (Botox/Vistabel, Allergan Inc) compared with placebo for the improvement of crow's feet. Methods Subjects received a single bilateral treatment of 18, 12, 6, or 3 U of BTX-A or placebo injected into the lateral aspect of the orbicularis oculi muscle (parallel-group, double,blind design). Investigators and subjects rated crow's feet severity at maximum smile on day 7 and at 30-day intervals from days 30 to 180. Results As observed by both investigators and subjects, all doses of BTX-A resulted in improvements in crow's feet severity when compared with placebo. A dose-dependent treatment effect for efficacy was observed, with higher doses having an increased magnitude and duration of effect. However, a clear differentiation between the 18 U and 12 U doses was not apparent. Few adverse events were reported, with no statistically significant differences between BTX-A and placebo in the incidence of subjects experiencing adverse events. Conclusion BTX-A is safe and effective in decreasing the severity of crow's feet, with 12 U per side suggested as the most appropriate dose. THIS STUDY WAS FUNDED BY ALLERGAN, WHICH WAS ALSO INVOLVED IN THE DESIGN AND CONDUCT OF THE STUDY; COLLECTION, MANAGEMENT, ANALYSIS, AND INTERPRETATION OF THE DATA; AND PREPARATION, REVIEW, AND APPROVAL OF THE MANUSCRIPT. DRS. LOWE AND FRACZEK ARE PAID CONSULTANTS FOR ALLERGAN, DRS. KUMAR AND EADIE ARE EMPLOYEES OF ALLERGAN, AND DRS. LOWE AND KUMAR HOLD STOCK OPTIONS. [source]

    THE PROCYCLICAL LEVERAGE EFFECT OF COLLATERAL VALUE ON BANK LOANS,EVIDENCE FROM THE TRANSACTION DATA OF TAIWAN

    ECONOMIC INQUIRY, Issue 2 2007
    NAN-KUANG CHEN
    We investigated the empirical relationship between firms' collateral values and land-secured loans over asset price cycles. A simultaneous equation model of loan demand and supply was estimated using a transaction-level data set from Taiwan. The data set contains collateral information and identifies lenders and borrowers. We found that the value of collateralizable assets has positive and significant effects on loan amounts and that the leverage effect of collateral is procyclical to asset price cycles. Firms in the electronics industry, the star industry in the sample period, are found to borrow more than other firms do at each marginal dollar of collateral. (JEL C50, E30, G20) [source]

    PROPOSAL FOR A NEW MEASURE OF CORRUPTION, ILLUSTRATED WITH ITALIAN DATA

    ECONOMICS & POLITICS, Issue 1 2005
    Miriam A. Golden
    Standard cross-national measures of corruption are assembled through surveys. We propose a novel alternative objective measure that consists of the difference between a measure of the physical quantities of public infrastructure and the cumulative price government pays for public capital stocks. Where the difference is larger between the monies spent and the existing physical infrastructure, more money is being siphoned off to mismanagement, fraud, bribes, kickbacks, and embezzlement; that is, corruption is greater. We create this measure for Italy's 95 provinces and 20 regions as of the mid-1990s, controlling at the regional level for possible differences in the costs of public construction. [source]

    A COMPARISON OF THE FAGERSTRÖM TEST FOR NICOTINE DEPENDENCE AND SMOKING PREVALENCE ACROSS COUNTRIES: UPDATED DATA FROM SPAIN

    ADDICTION, Issue 2 2009
    MARCELA FU
    No abstract is available for this article. [source]

    ACCUMULATING DOBZHANSKY-MULLER INCOMPATIBILITIES: RECONCILING THEORY AND DATA

    EVOLUTION, Issue 6 2004
    John J. Welch
    Abstract Theoretical models of the accumulation of Dobzhansky-Muller incompatibilities (DMIs) are studied, and in particular, the framework introduced by Orr (1995) and a verbal model introduced by Kondrashov et al. (2002). These models embody very different assumptions about the relationship between the substitution process underlying evolutionary divergence and the formation of incompatibilities. These differences have implications for our ability to make inferences about the divergence from patterns in the relevant data. With this in mind, the models are investigated for their ability to account for three patterns evident in this data: (1) the asymmetrical nature of incompatibilities under reciprocal introgression; (2) the finding that multiple concurrent introgressions may be necessary for an incompatibility to form; and (3) the finding that the probability of obtaining an incompatibility by introgressing a single amino acid remains roughly constant over a wide range of genetic distances. None of the models available in the literature can account for all of the empirical patterns. However, modified versions of the models can do so. Ways of discriminating between the different models are then discussed. [source]

    COLONY SEX RATIOS IN THE FACULTATIVELY POLYGYNOUS ANT PHEIDOLE PALLIDULA: A REANALYSIS WITH NEW DATA

    EVOLUTION, Issue 5 2004
    Ken R. Helms
    Abstract A recent study by Fournier et al. (2003) provides important new information on sex allocation in the ant Pheidole pallidula, and proposes a new scenario for sex-ratio evolution in P. pallidula and similar species. However, Helms proposed to the authors that two important conclusions of the study were questionable because of potential problems with the analyses. Here we provide new data and a reanalysis that strengthens the conclusion that colony sex ratio is associated with breeding system (i.e., polygyny or monogyny). However, the proposal that colonies shift from monogyny to polygyny when they become larger and more productive is weakened because there is substantial overlap in productivity between monogynous and polygynous colonies. [source]

    ARCHIVING OF SUPPLEMENTARY DATA

    EVOLUTION, Issue 3 2004
    Article first published online: 9 MAY 200
    No abstract is available for this article. [source]

    ARCHIVING OF SUPPLEMENTARY DATA

    EVOLUTION, Issue 1 2004
    Article first published online: 9 MAY 200
    No abstract is available for this article. [source]

    CALIBRATING A MOLECULAR CLOCK FROM PHYLOGEOGRAPHIC DATA: MOMENTS AND LIKELIHOOD ESTIMATORS

    EVOLUTION, Issue 10 2003
    Michael J. Hickerson
    Abstract We present moments and likelihood methods that estimate a DNA substitution rate from a group of closely related sister species pairs separated at an assumed time, and we test these methods with simulations. The methods also estimate ancestral population size and can test whether there is a significant difference among the ancestral population sizes of the sister species pairs. Estimates presented in the literature often ignore the ancestral coalescent prior to speciation and therefore should be biased upward. The simulations show that both methods yield accurate estimates given sample sizes of five or more species pairs and that better likelihood estimates are obtained if there is no significant difference among ancestral population sizes. The model presented here indicates that the larger than expected variation found in multitaxa datasets can be explained by variation in the ancestral coalescence and the Poisson mutation process. In this context, observed variation can often be accounted for by variation in ancestral population sizes rather than invoking variation in other parameters, such as divergence time or mutation rate. The methods are applied to data from two groups of species pairs (sea urchins and Alpheus snapping shrimp) that are thought to have separated by the rise of Panama three million years ago. [source]

    EXPLAINING THE UTILIZATION OF RELATIVE PERFORMANCE EVALUATION IN LOCAL GOVERNMENT: A MULTI-THEORETICAL STUDY USING DATA FROM SWEDEN

    FINANCIAL ACCOUNTABILITY & MANAGEMENT, Issue 2 2009
    Tobias Johansson
    One of the more lasting imprints that New Public Management (NPM) has made in the public sector is an increase in the popularity of performance measurement. In Sweden, performance measurement has gained popularity in the public sector, not least at the local government level with the use of relative performance evaluation (RPE). Because utilization of RPE is a decentralized and optional mode of governance, a somewhat heterogeneous practice has evolved. The aim of this paper is to examine the causes of this differentiated practice. We jointly examine economic, political and institutional/cultural explanations in order to account for the utilization of RPE. The empirical material consists of archival data and a questionnaire sent to all Swedish municipalities in late 2005. We show that RPE adoption and use partly has different antecedents and that the institutional/cultural perspective appears to have greater explanatory power than economic and political, not least as a consequence of the potential to explain decoupling and the importance of change facilitating capabilities. The investigation contributes specifically to the literature on the utilization of RPE in local governments and more generally to the literature on why and to what extent management accounting practices are utilized. [source]

    CREDIT CONSTRAINTS IN THE MARKET FOR CONSUMER DURABLES: EVIDENCE FROM MICRO DATA ON CAR LOANS,

    INTERNATIONAL ECONOMIC REVIEW, Issue 2 2008
    Orazio P. Attanasio
    We investigate the significance of borrowing constraints in the market for consumer loans. Using data from the Consumer Expenditure Survey on auto loan contracts we estimate the elasticities of loan demand with respect to interest rate and maturity. We find that, with the exception of high income households, consumers are very responsive to maturity and less responsive to interest rate changes. Both elasticities vary with household income, with the maturity elasticity decreasing and the interest rate elasticity increasing with income. We argue that these results are consistent with the presence of binding credit constraints in the auto loan market. [source]

    AGE AND ACUTE MOUNTAIN SICKNESS: EXAMINING THE DATA

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2005
    Jeremy Graham DO
    No abstract is available for this article. [source]

    COMBINING REVEALED AND STATED PREFERENCE DATA TO ESTIMATE THE NONMARKET VALUE OF ECOLOGICAL SERVICES: AN ASSESSMENT OF THE STATE OF THE SCIENCE

    JOURNAL OF ECONOMIC SURVEYS, Issue 5 2008
    John C. Whitehead
    Abstract This paper reviews the marketing, transportation and environmental economics literature on the joint estimation of revealed preference (RP) and stated preference (SP) data. The RP and SP approaches are first described with a focus on the strengths and weaknesses of each. Recognizing these strengths and weaknesses, the potential gains from combining data are described. A classification system for combined data that emphasizes the type of data combination and the econometric models used is proposed. A methodological review of the literature is pursued based on this classification system. Examples from the environmental economics literature are highlighted. A discussion of the advantages and disadvantages of each type of jointly estimated model is then presented. Suggestions for future research, in particular opportunities for application of these models to environmental quality valuation, are presented. [source]

    SOLID FOODS FREEZE-DRYING SIMULATION AND EXPERIMENTAL DATA

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2005
    S. KHALLOUFI
    ABSTRACT This article presents a mathematical model describing the unsteady heat and mass transfer during the freeze drying of biological materials. The model was built from the mass and energy balances in the dried and frozen regions of the material undergoing freeze drying. A set of coupled nonlinear partial differential equations permitted the description of the temperature and pressure profiles, together with the position of the sublimation interface. These equations were transformed to a finite element scheme and numerically solved using the Newton-Raphson approach to represent the nonlinear problem and the interface position. Most parameters involved in the model (i.e., thermal conductivity, specific heat, density, heat and mass transfer coefficients etc.) were obtained from experimental data cited in the literature. The dehydration kinetics and the temperature profiles of potato and apple slabs were experimentally determined during freeze drying. The simulation results agreed closely with the water content experimental data. The prediction of temperature profiles within the solid was, however, less accurate. [source]

    MULTIVARIATE QUALITY CONTROL WITH APPLICATIONS TO SENSORY DATA

    JOURNAL OF FOOD QUALITY, Issue 6 2000
    DANIEL M. ENNIS
    ABSTRACT Sensory perceptions of consumer products are generally multivariate. Quality assurance of these products depends on methods that account for multidimensionality. In this paper it is shown how to set multivariate specifications and to use them to establish control charts and acceptance sampling plans for sensory measures of food and beverage products. OC curves describing the operating characteristics of the control charts and the sampling plans are given. [source]

    PATHOGEN DETECTION IN FOOD MICROBIOLOGY LABORATORIES: AN ANALYSIS OF QUALITATIVE PROFICIENCY TEST DATA, 1999,2007

    JOURNAL OF FOOD SAFETY, Issue 4 2009
    DANIEL C. EDSON
    ABSTRACT The objective of this study was to assess laboratories' ability to detect or rule out the presence of four common food pathogens: Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes and Campylobacter spp. To do this, qualitative proficiency test data provided by one proficiency test provider from 1999 to 2007 were examined. The annual and cumulative 9-year percentages of false-negative and false-positive responses were calculated. The cumulative 9-year false-negative rates were 7.8% for E. coli O157:H7, 5.9% for Salmonella spp., 7.2% for L. monocytogenes and 13.6% for Campylobacter spp. Atypical strains and low concentrations of bacteria were more likely to be missed, and the data showed no trend of improving performance over time. Percentages of false-positive results were below 5.0% for all four pathogens. PRACTICAL APPLICATIONS The results imply that food testing laboratories often fail to detect the presence of these four food pathogens in real food specimens. To improve pathogen detection, supervisors should ensure that testing personnel are adequately trained, that recommended procedures are followed correctly, that samples are properly prepared, that proper conditions (temperature, atmosphere and incubation time) are maintained for good bacterial growth and that recommended quality control procedures are followed. Supervisors should also always investigate reasons for unsatisfactory proficiency test results and take corrective action. Finally, more research is needed into testing practices and proficiency test performance in food testing laboratories. [source]

    DROWNING IN DATA: Informatics and modeling challenges in a data-rich networked world

    AICHE JOURNAL, Issue 1 2009
    Venkat Venkatasubramanian
    First page of article [source]

    A FUZZY LOGIC APPROACH TO ESTIMATING HYDRAULIC FLOW UNITS FROM WELL LOG DATA: A CASE STUDY FROM THE AHWAZ OILFIELD, SOUTH IRAN

    JOURNAL OF PETROLEUM GEOLOGY, Issue 1 2009
    A. Kadkhodaie-Ilkhchi
    Porosity-permeability relationships in the framework of hydraulic flow units can be used to characterize heterogeneous reservoir rocks. Porosity is a volumetric parameter whereas permeability is a measure of a rock's flow properties and depends on pore distribution and connectivity. Thus zonation of a reservoir using flow zone indicators and the identification of flow units can be used to evaluate reservoir quality based on porosity-permeability relationships. In the present study, we attempt to make a quantitative correlation between flow units and well log responses using fuzzy logic in the mixed carbonate-clastic Asmari Formation at the Ahwaz oilfield, South Iran. A hybrid neuro-fuzzy approach was used to verify the results of fuzzy modelling. For this purpose, well log and core data from three wells at Ahwaz were used to make an intelligent formulation between core-derived flow units and well log responses. Data from a separate well was used for evaluation and validation of the results. The results of this study demonstrate that there is a good agreement between core-derived and fuzzy-logic derived flow units. Fuzzy logic was successful in modelling flow units from well logs at well locations for which no core data was available. [source]

    IDENTIFICATION OF SALT FEATURES IN SEISMIC DATA

    JOURNAL OF PETROLEUM GEOLOGY, Issue 4 2008
    M. K. Jenyon
    Deciding on the viability of a salt deposit as a possible site for storage-cavern solution mining requires detailed geological studies of the salt and of its confining formations. Borehole data alone can seldom deliver the information required for such a study. It can impart great detail of the subsurface but only at the actual borehole location in an area. The most practical approach to developing 3D information is to carry out a seismic survey tied in to one or more boreholes which have been logged geophysically Ideally, a high-resolution seismic survey is needed to study relatively shallow zones of the subsurface and resolve the top and base of fairly thin beds. However in some cases it is possible to use "reach-me-down" seismic data acquired previously during hydrocarbon exploration. Although these data were not designed to meet the requirements of salt deposit studies, they may still be adequate for the purpose. Their use will lead to quicker and lower-cost results than the commissioning of a full field seismic survey with concomitant processing, although in both cases a seismic interpretation would be required. [source]

    THERMAL HISTORY RECONSTRUCTION IN THE SOROOSH AND NOWROOZ FIELDS, PERSIAN GULF, BASED ON APATITE FISSION TRACK ANALYSIS AND VITRINITE REFLECTANCE DATA

    JOURNAL OF PETROLEUM GEOLOGY, Issue 2 2008
    A. Bashari
    The thermal history of the sedimentary successions at the Soroosh-17, Soroosh-02 and Nowrooz-16 wells in the northern Persian Gulf have been studied using apatite fission track analysis and vitrinite reflectance data. These data were used to identify and quantify episodes of heating and cooling which have affected the sections penetrated by these wells. This information was synthesised to provide a thermal history framework for the wells, within which the history of hydrocarbon generation, as well as regional structural development, can be understood. Preliminary hydrocarbon generation histories are presented for the Soroosh and Nowrooz oilfields and nearby areas. Modelling of hydrocarbon generation histories based on the AFTA- and VR-derived thermal histories, assuming a dominant Type III kerogen for possible Albian Kazhdumi Formation source rocks and a dominant Type II kerogen for possible Neocomian Fahliyan (Lower Ratawi) Formation source rock, suggest that local sourcing of oil from the Kazhdumi Formation is unlikely. The most likely source rock for oil in the Burgan Formation reservoir at Soroosh-17 and Nowrooz-16 is interpreted to be the Fahliyan Formation based on the available data. On the other hand, speculative modelling of the Hendijan-I well down-dip from the Nowrooz field does allow some oil to be generated from the Kazhdumi sequence at that location, and this might be available for migration to the Nowrooz field. [source]

    A REVIEW OF GEOLOGICAL DATA THAT CONFLICT WITH THE PARADIGM OF CATAGENIC GENERATION AND MIGRATION OF OIL

    JOURNAL OF PETROLEUM GEOLOGY, Issue 3 2005
    H. Hugh Wilson
    The majority of petroleum geologists today agree that the complex problems that surround the origin, generation, migration and accumulation of hydrocarbons can be resolved by accepting the geochemical conclusion that the process originates by catagenic generation in deeply-buried organically-rich source rocks. These limited source rock intervals are believed to expel hydrocarbons when they reach organic maturity in oil kitchens. The expelled oil and gas then follow migration pathways to traps at shallower levels. However, there are major geological obstacles that cast doubt upon this interpretation. The restriction of the source rock to a few organically rich levels in a basin forces the conclusion that the basin plumbing system is leaky and allows secondary horizontal and vertical migration through great thicknesses of consolidated sedimentary rocks in which there are numerous permeability barriers that are known to effectively prevent hydrocarbon escape from traps. The sourcing of lenticular traps points to the enclosing impermeable envelope as the logical origin of the trapped hydrocarbons. The lynch-pin of the catagenic theory of hydrocarbon origin is the expulsion mechanism from deeply-buried consolidated source rock under high confining pressures. This mechanism is not understood and is termed an "enigma". Assuming that expulsion does occur, the pathways taken by the hydrocarbons to waiting traps can be ascertained by computer modelling of the basin. However, subsurface and field geological support for purported migration pathways has yet to be provided. Many oilfield studies have shown that oil and gas are preferentially trapped in synchronous highs that were formed during, or very shortly after, the deposition of the charged reservoir. An unresolved problem is how catagenically generated hydrocarbons, expelled during a long-drawn-out maturation period, can have filled synchronous highs but have avoided later traps along the assumed migration pathways. From many oilfield studies, it has also been shown that the presence of hydrocarbons inhibits diagenesis and compaction of the reservoir rock. This "Füchtbauer effect" points to not only the early charging of clastic and carbonate reservoirs, but also to the development of permeability barriers below the early-formed accumulations. These barriers would prevent later hydrocarbon additions during the supposed extended period of expulsion from an oil kitchen. Early-formed traps that have been sealed diagenetically will retain their charge even if the trap is opened by later structural tilting. Diagenetic traps have been discovered in clastic and carbonate provinces but their recognition as viable exploration targets is discouraged by present-day assumptions of late hydrocarbon generation and a leaky basin plumbing system. Because there are so many geological realities that cast doubt upon the assumptions that devolve from the paradigm of catagenic generation, the alternative concept of early biogenic generation and accumulation of immature oil, with in-reservoir cracking during burial, is again worthy of serious consideration. This concept envisages hydrocarbon generation by bacterial activity in many anoxic environments and the charging of synchronous highs from adjacent sources. The resolution of the fundamental problem of hydrocarbon generation and accumulation, which is critical to exploration strategies, should be sought in the light of a thorough knowledge of the geologic factors involved, rather than by computer modelling which may be guided by questionable geochemical assumptions. [source]

    UPPER TRIASSIC-MIDDLE JURASSIC STRATIGRAPHY AND SEDIMENTOLOGY IN THE NE QAIDAM BASIN, NW CHINA: PETROLEUM GEOLOGICAL SIGNIFICANCE OF NEW OUTCROP AND SUBSURFACE DATA

    JOURNAL OF PETROLEUM GEOLOGY, Issue 4 2003
    Yang Yongtai
    Although Mesozoic source and reservoir rocks are known to occur at oilfields in the northern Qaidam Basin (NW China), the precise identification and distribution of Mesozoic rocks in the subsurface are outstanding problems. The Dameigou locality has in the past been considered as the type section for Lower-Middle Jurassic strata in northern Qaidam. Previous studies have concluded that the onset of non-marine sedimentation here took place in the Early Jurassic; and that Mesozoic strata penetrated by wells in the Lenghu structural zone are Middle Jurassic. In this paper, we present new data from the Lengke-1 well, drilled in the Lenghu structural zone in 1997. This data indicates the existence of a more extensive pre-Middle Jurassic stratigraphy than has previously been recognized. Biostratigraphic data together with regional seismic mapping suggest that the pre-Middle Jurassic succession at Lengke-1 includes both Late Triassic and Early Jurassic deposits. The Late Triassic sedimentary rocks appear to have been deposited in local half graben, some of which were later inverted during Jurassic, Cretaceous and Cenozoic tectonism. Lower and Middle Jurassic strata (lacustrine and fluvial deposits) are present in the SW and NE parts of the Lenghu structural zone, respectively. Extensive organic-rich intervals are present in both successions. Lower Jurassic lacustrine mudstones may represent a previously under-appreciated, and potentially large, source rock sequence. [source]

    PSEUDULVELLA AMERICANA BELONGS TO THE ORDER CHAETOPELTIDALES (CLASS CHLOROPHYCEAE), EVIDENCE FROM ULTRASTRUCTURE AND SSU RDNA SEQUENCE DATA,

    JOURNAL OF PHYCOLOGY, Issue 4 2006
    M. Virginia Sanchez-Puerta
    The genus Pseudulvella Wille 1909 includes epiphytic, freshwater, or marine disk-shaped green microalgae that form quadriflagellate zoospores. No ultrastructural or molecular studies have been conducted on the genus, and its evolutionary relationships remain unclear. The purpose of the present study is to describe the life history, ultrastructural features, and phylogenetic affiliations of Pseudulvella americana (Snow) Wille, the type species of the genus. Thalli of this microalga were prostrate and composed of radiating branched filaments that coalesced to form a disk. Vegetative cells had a pyrenoid encircled by starch plates and traversed by one or two convoluted cytoplasmic channels. They had well-defined cell walls without plasmodesmata. Asexual reproduction was by means of tetraflagellate zoospores formed in numbers of two to eight from central cells of the thallus. The flagellar apparatus of zoospores was cruciate, with four basal bodies and four microtubular roots. The paired basal bodies lay directly opposite (DO) one another. The microtubular root system had a 5-2-5-2 alternation pattern, where the "s" roots contained five microtubules in a four-over-one configuration. A tetralobate nonstriated distal fiber connected all four basal bodies. A wedge-shaped proximal sheath subtended each of the basal bodies. The ultrastructural features of the zoospores were those of members of the order Chaetopeltidales. Phylogenetic analyses based on SSU rDNA placed P. americana sister to Chaetopeltis orbicularis in a well-supported Chaetopeltidales clade. Such a combination of features confirmed that this alga is a member of the order Chaetopeltidales. [source]

    INTER- AND INTRASPECIFIC VARIATION OF THE PSEUDO-NITZSCHIA DELICATISSIMA COMPLEX (BACILLARIOPHYCEAE) ILLUSTRATED BY RRNA PROBES, MORPHOLOGICAL DATA AND PHYLOGENETIC ANALYSES,

    JOURNAL OF PHYCOLOGY, Issue 2 2006
    Nina Lundholm
    A study of 25 cultures tentatively identified as Pseudo-nitzschia delicatissima (Cleve) Heiden, and originating from geographically widely distributed locations, showed both morphological and genetic variation among strains. Use of rRNA-targeted DNA probes on 17 different strains showed large variation in the hybridization patterns. Detailed morphological studies placed the isolates into three groups. The sample on which the neotype of P. delicatissima is based was also examined, and used to establish the morphological identity of P. delicatissima. Phylogenetic analyses of 16 strains, based on sequences of internal transcriber spacer 1 (ITS1), 5.8S and ITS2 of the nuclear-encoded rDNA, supported the morphological observations and the hybridization studies, and revealed large genetic variation among strains. A combination of the morphological and molecular findings resulted in the description of two new species, P. decipiens sp. nov. and P. dolorosa sp. nov. P. dolorosa has a mixture of one or two rows of poroids in the striae whereas P. delicatissima always has two rows. In addition, P. dolorosa has wider valves and a lower density of poroids. P. decipiens differs from P. delicatissima by a higher density of striae on the valve face as well as a higher density of poroids on the girdle bands. Among the strains referred to P. delicatissima, an epitype was selected. Large genetic variation was found among the P. delicatissima strains and a subdivision into two major clades represent cryptic species. [source]

    EFFECT OF TAXON SAMPLING, CHARACTER WEIGHTING, AND COMBINED DATA ON THE INTERPRETATION OF RELATIONSHIPS AMONG THE HETEROKONT ALGAE,

    JOURNAL OF PHYCOLOGY, Issue 2 2003
    Leslie R. Goertzen
    Nuclear ribosomal small subunit and chloroplast rbcL sequence data for heterokont algae and potential outgroup taxa were analyzed separately and together using maximum parsimony. A series of taxon sampling and character weighting experiments was performed. Traditional classes (e.g. diatoms, Phaeophyceae, etc.) were monophyletic in most analyses of either data set and in analyses of combined data. Relationships among classes and of heterokont algae to outgroup taxa were sensitive to taxon sampling. Bootstrap (BS) values were not always predictive of stability of nodes in taxon sampling experiments or between analyses of different data sets. Reweighting sites by the rescaled consistency index artificially inflates BS values in the analysis of rbcL data. Inclusion of the third codon position from rbcL enhanced signal despite the superficial appearance of mutational saturation. Incongruence between data sets was largely due to placement of a few problematic taxa, and so data were combined. BS values for the combined analysis were much higher than for analyses of each data set alone, although combining data did not improve support for heterokont monophyly. [source]

    MOLECULAR AND MORPHOLOGICAL DATA IDENTIFY A CRYPTIC SPECIES COMPLEX IN ENDOPHYTIC MEMBERS OF THE GENUS COLEOCHAETE BRÉB. (CHAROPHYTA: COLEOCHAETACEAE),

    JOURNAL OF PHYCOLOGY, Issue 6 2002
    Matthew T. Cimino
    The genus Coleochaete Bréb. is a relatively small group of freshwater microscopic green algae with about 15 recognized species. Although Coleochaete has long been considered to be a close relative of embryophytes, a comprehensive study of the genus has not been published since Pringsheim's 1860 monograph. As part of a systematic study of Coleochaete, we investigated four accessions of the genus that are morphologically similar to the endophytic species C. nitellarum Jost. Each of the four cultures was determined to be capable of endophytic growth in Nitella C. A. Agardh, a member of the closely related order Charales. Maximum likelihood and maximum parsimony analyses were performed on nucleotide data from the chloroplast genes atpB and rbcL that were sequenced from 16 members of the Coleochaetales and from other members of the Charophyceae, embryophytes, and outgroup taxa. These analyses indicate that the Coleochaetales are monophyletic and that the endophytic accessions are members of the scutata group of species. In addition, cell size and nucleotide data suggest that at least three different endophytic species may be represented. Herbivory, nutritional benefits, and substrate competition are three hypotheses that could explain the evolution and maintenance of the endophytic habit in Coleochaete. These data also imply that diversity in the genus may be markedly underestimated. [source]