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 A Uniform Database of 2.2-16.5 μm Spectra from the ISOCAM CVF SpectrometerWe present all ISOCAM circular variable filter (CVF) spectra that covermore than one-third of the 2.2-16.5 μm spectral range of theinstrument. The 364 spectra have been classified according to theclassification system of Kraemer et al., as modified by Hodge et al. toaccount for the shorter wavelength range. Prior to classification, thespectra were processed and recalibrated to create a uniform database.Aperture photometry was performed at each wavelength centered on thebrightest position in each image field and the various spectral segmentsmerged into a single spectrum. The aperture was the same for all scalesizes of the images. Since this procedure differs fundamentally fromthat used in the initial ISOCAM calibration, a recalibration of thespectral response of the instrument was required for the aperturephotometry. The recalibrated spectra and the software used to createthem are available to the community on-line via the ISO Data Archive.Several new groups were added to the KSPW system to describe spectrawith no counterparts in either the SWS or PHT-S databases: CA, E/SA,UE/SA, and SSA. The zodiacal dust cloud provides the most commonbackground continuum to the spectral features, visible in almost 40% ofthe processed sources. The most characteristic and ubiquitous spectralfeatures observed in the CVF spectral atlas are those of theunidentified infrared bands (UIR), which are typically attributed toultraviolet-excited fluorescence of large molecules containing aromatichydrocarbons. The UIR features commonly occur superimposed on thezodiacal background (18%) but can also appear in conjunction with otherspectral features, such as fine-structure emission lines or silicateabsorption. In at least 13 of the galaxies observed, the pattern of UIRemission features has been noticeably shifted to longer wavelengths.Based on observations with the Infrared Space Observatory, a EuropeanSpace Agency (ESA) project with instruments funded by ESA Member States(especially the Principal Investigator countries: France, Germany, theNetherlands, and the United Kingdom) and with the participation of theInstitute of Space and Astronautical Science (ISAS) and the NationalAeronautics and Space Administration (NASA). Properties of isolated disk galaxiesWe present a new sample of northern isolated galaxies, which are definedby the physical criterion that they were not affected by other galaxiesin their evolution during the last few Gyr. To find them we used thelogarithmic ratio, f, between inner and tidal forces acting upon thecandidate galaxy by a possible perturber. The analysis of thedistribution of the f-values for the galaxies in the Coma cluster leadus to adopt the criterion f ≤ -4.5 for isolated galaxies. Thecandidates were chosen from the CfA catalog of galaxies within thevolume defined by cz ≤5000 km s-1, galactic latitudehigher than 40o and declination ≥-2.5o. Theselection of the sample, based on redshift values (when available),magnitudes and sizes of the candidate galaxies and possible perturberspresent in the same field is discussed. The final list of selectedisolated galaxies includes 203 objects from the initial 1706. The listcontains only truly isolated galaxies in the sense defined, but it is byno means complete, since all the galaxies with possible companions underthe f-criterion but with unknown redshift were discarded. We alsoselected a sample of perturbed galaxies comprised of all the diskgalaxies from the initial list with companions (with known redshift)satisfying f ≥ -2 and \Delta(cz) ≤500 km s-1; a totalof 130 objects. The statistical comparison of both samples showssignificant differences in morphology, sizes, masses, luminosities andcolor indices. Confirming previous results, we found that late spiral,Sc-type galaxies are, in particular, more frequent among isolatedgalaxies, whereas Lenticular galaxies are more abundant among perturbedgalaxies. Isolated systems appear to be smaller, less luminous and bluerthan interacting objects. We also found that bars are twice as frequentamong perturbed galaxies compared to isolated galaxies, in particularfor early Spirals and Lenticulars. The perturbed galaxies have higherLFIR/LB and Mmol/LB ratios,but the atomic gas content is similar for the two samples. The analysisof the luminosity-size and mass-luminosity relations shows similartrends for both families, the main difference being the almost totalabsence of big, bright and massive galaxies among the family of isolatedsystems, together with the almost total absence of small, faint and lowmass galaxies among the perturbed systems. All these aspects indicatethat the evolution induced by interactions with neighbors would proceedfrom late, small, faint and low mass Spirals to earlier, bigger, moreluminous and more massive spiral and lenticular galaxies, producing atthe same time a larger fraction of barred galaxies but preserving thesame relations between global parameters. The properties we found forour sample of isolated galaxies appear similar to those of high redshiftgalaxies, suggesting that the present-day isolated galaxies could bequietly evolved, unused building blocks surviving in low densityenvironments.Tables \ref{t1} and \ref{t2} are only available in electronic form athttp://www.edpsciences.org Redshift-Distance Survey of Early-Type Galaxies: Spectroscopic DataWe present central velocity dispersions and Mg2 line indicesfor an all-sky sample of ~1178 elliptical and S0 galaxies, of which 984had no previous measures. This sample contains the largest set ofhomogeneous spectroscopic data for a uniform sample of ellipticalgalaxies in the nearby universe. These galaxies were observed as part ofthe ENEAR project, designed to study the peculiar motions and internalproperties of the local early-type galaxies. Using 523 repeatedobservations of 317 galaxies obtained during different runs, the dataare brought to a common zero point. These multiple observations, takenduring the many runs and different instrumental setups employed for thisproject, are used to derive statistical corrections to the data and arefound to be relatively small, typically <~5% of the velocitydispersion and 0.01 mag in the Mg2 line strength. Typicalerrors are about 8% in velocity dispersion and 0.01 mag inMg2, in good agreement with values published elsewhere. A new catalogue of ISM content of normal galaxiesWe have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of normality''. Thedefinition of a normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5 A Radio Survey for Linear and Circular Polarization in Low-Luminosity Active Galactic NucleiWe conducted a Very Large Array survey of 11 low-luminosity activegalactic nuclei (LLAGNs) for linear and circular polarization at 8.4GHz. We detected circular polarization in one source (M81*) and linearpolarization in three sources. Sensitivity limits were ~0.1% for bothmodes of polarization in nine of 11 sources. The detections confirm theimportance of nonthermal emission in LLAGNs. However, detection ratesfor circular and linear polarization are lower for these sources thanfor more powerful AGNs. Fractional linear polarization in detectedsources is also lower than in more powerful AGNs. The weak linearpolarization in the survey sources indicates their overall similarity toSgr A*. Confusion with thermal sources, depolarization, and weaker, lessextended jets may contribute to these differences. We detect a rotationmeasure >~7×104 rad m-2 for NGC 4579.This may arise from magnetized plasma in the accretion, outflow, orinterstellar regions. Inverted spectra are present in both M81* and SgrA* and absent from all sources in which circular polarization is notdetected. This suggests that optical depth effects are important in thecreation of circular polarization. The UZC-SSRS2 Group CatalogWe apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers. A catalogue and analysis of X-ray luminosities of early-type galaxiesWe present a catalogue of X-ray luminosities for 401 early-typegalaxies, of which 136 are based on newly analysed ROSAT PSPC pointedobservations. The remaining luminosities are taken from the literatureand converted to a common energy band, spectral model and distancescale. Using this sample we fit the LX:LB relationfor early-type galaxies and find a best-fit slope for the catalogue of~2.2. We demonstrate the influence of group-dominant galaxies on the fitand present evidence that the relation is not well modelled by a singlepower-law fit. We also derive estimates of the contribution to galaxyX-ray luminosities from discrete-sources and conclude that they provideLdscr/LB~=29.5ergs-1LBsolar-1. Wecompare this result with luminosities from our catalogue. Lastly, weexamine the influence of environment on galaxy X-ray luminosity and onthe form of the LX:LB relation. We conclude thatalthough environment undoubtedly affects the X-ray properties ofindividual galaxies, particularly those in the centres of groups andclusters, it does not change the nature of whole populations. Nearby Optical Galaxies: Selection of the Sample and Identification of GroupsIn this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales. Arcsecond Positions of UGC GalaxiesWe present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only. Groups of galaxies. III. Some empirical characteristics.Not Available An image database. II. Catalogue between δ=-30deg and δ=70deg.A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect. A multiparametric analysis of the Einstein sample of early-type galaxies. 1: Luminosity and ISM parametersWe have conducted bivariate and multivariate statistical analysis ofdata measuring the luminosity and interstellar medium of the Einsteinsample of early-type galaxies (presented by Fabbiano, Kim, &Trinchieri 1992). We find a strong nonlinear correlation betweenLB and LX, with a power-law slope of 1.8 +/- 0.1,steepening to 2.0 +/- if we do not consider the Local Group dwarfgalaxies M32 and NGC 205. Considering only galaxies with logLX less than or equal to 40.5, we instead find a slope of 1.0+/- 0.2 (with or without the Local Group dwarfs). Although E and S0galaxies have consistent slopes for their LB-LXrelationships, the mean values of the distribution functions of bothLX and LX/LB for the S0 galaxies arelower than those for the E galaxies at the 2.8 sigma and 3.5 sigmalevels, respectively. We find clear evidence for a correlation betweenLX and the X-ray color C21, defined by Kim,Fabbiano, & Trinchieri (1992b), which indicates that X-rayluminosity is correlated with the spectral shape below 1 keV in thesense that low-LX systems have relatively large contributionsfrom a soft component compared with high-LX systems. We findevidence from our analysis of the 12 micron IRAS data for our samplethat our S0 sample has excess 12 micron emission compared with the Esample, scaled by their optical luminosities. This may be due toemission from dust heated in star-forming regions in S0 disks. Thisinterpretation is reinforced by the existence of a strongL12-L100 correlation for our S0 sample that is notfound for the E galaxies, and by an analysis of optical-IR colors. Wefind steep slopes for power-law relationships between radio luminosityand optical, X-ray, and far-IR (FIR) properties. This last point arguesthat the presence of an FIR-emitting interstellar medium (ISM) inearly-type galaxies is coupled to their ability to generate nonthermalradio continuum, as previously argued by, e.g., Walsh et al. (1989). Wealso find that, for a given L100, galaxies with largerLX/LB tend to be stronger nonthermal radiosources, as originally suggested by Kim & Fabbiano (1990). We notethat, while LB is most strongly correlated withL6, the total radio luminosity, both LX andLX/LB are more strongly correlated with L6CO, the core radio luminosity. These points support the argument(proposed by Fabbiano, Gioia, & Trinchieri 1989) that radio cores inearly-type galaxies are fueled by the hot ISM. Multiwavelength Energy Distributions and Bolometric Luminosities of the 12 Micron Galaxy SampleAbstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...453..616S&db_key=AST The extended 12 micron galaxy sampleWe have selected an all-sky (absolute value of b greater than or equalto 25 deg) 12 micron flux-limited sample of 893 galaxies from the IRASFaint Source Catalog, Version 2 (FSC-2). We have obtained accurate totalfluxes in the IRAS wavebands by using the ADDSCAN procedure for allobjects with FSC-2 12 micron fluxes greater than 0.15 Jy and increasingflux densities from 12 to 60 microns, and defined the sample by imposinga survey limit of 0.22 Jy on the total 12 micron flux. Its completenessis verified, by means of the classical log N - log S andV/Vmax tests, down to 0.30 Jy, below which we have measuredthe incompleteness down to the survey limit, using the log N - log Splot, for our statistical analysis. We have obtained redshifts (mostlyfrom catalogs) for virtually all (98.4%) the galaxies in the sample.Using existing catalogs of active galaxies, we defined a subsample of118 objects consisting of 53 Seyfert 1s and quasars, 63 Seyfert 2s, andtwo blazars (approximately 13% of the full sample), which is the largestunbiased sample of Seyfert galaxies ever assembled. Since the 12 micronflux has been shown to be about one-fifth of the bolometric flux forSeyfert galaxies and quasars, the subsample of Seyferts (includingquasars and blazars) is complete not only to 0.30 Jy at 12 microns butalso with respect to a bolometric flux limit of approximately 2.0 x10-10 ergs/s/sq cm. The average value of V/Vmaxfor the full sample, corrected for incompleteness at low fluxes, is 0.51+/- 0.04, expected for a complete sample of uniformly distributedgalaxies, while the value for the Seyfert galaxy subsample is 0.46 +/-0.10. We have derived 12 microns and far-infrared luminosity functionsfor the AGNs, as well as for the entire sample. We extracted from oursample a complete subsample of 235 galaxies flux-limited (8.3 Jy) at 60microns. The 60 micron luminosity function computed for this subsampleis in satisfactory agreement with the ones derived from the brightgalaxy sample (BGS) and the deep high-galactic latitude sample, bothselected at 60 microns. A revised catalog of CfA1 galaxy groups in the Virgo/Great Attractor flow fieldA new identification of groups and clusters in the CfA1 Catalog ofHuchra et al. is presented, using a percolation algorithm to identifydensity enhancements. It is shown that in the resulting catalog,contamination by interlopers is significantly reduced. The Schechterluminosity function is redetermined, including the Malmquist bias. General study of group membership. II - Determination of nearby groupsWe present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog. An X-ray catalog and atlas of galaxiesAn X-ray catalog and atlas of galaxies observed with the EinsteinObservatory imaging instruments (IPC and HRI) are presented. The catalogcomprises 493 galaxies, including targets of pointed observations, andRSA or RC2 galaxies serendipitously included in Einstein fields. A totalof 450 of these galaxies were imaged well within the instrumentalfields, resulting in 238 detections and 2123 sigma upper limits. Theother galaxies were either at the edge of the visible field of view orconfused with other X-ray sources. For these a rough measure of theirX-ray emission is also given. The atlas shows X-ray contour maps ofdetected galaxies superposed on optical photographs and givesazimuthally averaged surface brightness profiles of galaxies detectedwith a high signal-to-noise ratio. A survey of small-scale extremes in extinction at low Galactic latitudes using IRAS galaxiesOptical CCD and 21 cm H I data are combined here via the Tully-Fisherrelation to study the Galactic extinction in the V an I bands over anangular scale of a few arcmin at absolute Galactic latitudes between 2and 16 deg. Extinctions in V and I bands are found to be linearlycorrelated with A(I) about 0.58 A(V), with no noticeable environmentaldependence and consistent with existing results of Galactic reddening.There is a large scatter in the simple linear relation with csc /b/,confirming the existence of 'holes' and patches at low Galacticlatitudes. The mean correlation between Galactic extinction and H Icolumn density over a comparable angular scale is also found to beconsistent with those at high latitudes over large angular scales.Correlation is also found between optical extinction and the IRAS 100micron sky brightness, and this sky brightness is only slightly worsethan H I column density as an indicator for optical extinction. The far-infrared properties of the CfA galaxy sample. I - The catalogIRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths. Radio-continuum sources in nearby and bright E/S0 galaxies - Active nuclei versus star formationResults of a sensitive VLA survey of nearby E/S0 galaxies are presented.The 204 galaxies surveyed, plus 12 additional galaxies with existing VLAimages, comprise a volume- and optical magnitude-limited sample. Thediscussion focuses on the relation between radio powers and opticalluminosities, whether the radio emission is driven by an active nucleusor by recent star formation, and what galaxian properties might enhancenuclear activity in an elliptical galaxy. It is suggested that the 67ellipticals in the sample should be targets of sensitive searches forHI, optical emission-line gas, and X-ray emitting gas. Radio-continuum sources in nearby and bright E/S0 galaxies - Sample selection and well-studied casesA volume-limited sample of 216 nearby and optically bright E/S0 galaxieshas been compiled. Twelve of the galaxies are confirmed radio sourcesfor which VLA images are available. Most of the remaining galaxies havepowers less than or of the order of 10 to the 21st-22nd W/Hz, and thisinformation is used to establish the parameters of a new VLA survey ofthese galaxies. The basic optical properties of the galaxies in thesample are tabulated. The 12 micron galaxy sample. I - Luminosity functions and a new complete active galaxy sampleAn all-sky 12 micron flux-limited sample of active galaxies was selectedfrom the IRAS Point Source Catalog. Most of the sample galaxies are inexisting catalogs, and 99 percent have measured redshifts. The 12-micronand the far-infrared luminosity functions of active and normal galaxiesare derived using IRAS co-added data. A total of 22 percent of thesample galaxies harbor active nuclei. The sample consists almost equallyof Seyfert 1, Seyfert 2, and LINER nuclei. The derived luminosityfuctions for Seyfert 1 and Seyfert 2 galaxies are indistinguishable fromthose of the optically selected CfA sample. Thus, 12 micron selection isthe most efficient available technique for finding complete activegalaxy samples. On the relationship between radio emission and optical properties in early-type galaxiesTo study the origin of radio activity in early-type galaxies, thepossible dependence of their radio emission on basic optical parameters,such as the absolute magnitude, the central velocity dispersion sigma,and the mean surface brightness mu is explored. A sample of 743 E and SOgalaxies is used which is based on three independent radio surveys ofoptically selected galaxies with virtually complete information onmagnitudes, morphological types, redshift distances, diameters, andradio fluxes. For both E and SO galaxies, only the absolute magnitudeappears to be directly related to the radio activity, while sigma and mudo not. Also, a significant dependence of the apparent flattening onradio power is confirmed for E galaxies. Some relevant implications ofthese results are discussed. Current star formation as the origin of kiloparsec-scale radio sources in nearby E/S0 galaxiesVLA images at 6 cm of eight nearby galaxies show extended emission onkpc scales. Optical data reveal that six of the host galaxies are likelyto be genuine ellipticals or lenticulars, and two are possiblyellipticals or lenticulars. All eight galaxies have substantial FIRluminosities. One or more gas-rich companions are identified for each ofseven galaxies. Cosmology from a galaxy group catalog. I - BinariesA new, completely objective group-finding algorithm is described andapplied to the CfA redshift catalog. The binary galaxies are isolatedfor analysis. The assumptions underlying the analysis are (1) that lighttraces mass, (2) that our binary galaxy subsets are representative lighttracers, and (3) that the binary orbits are circular. The primary resultof the work is that the resulting bias-free binary catalogs are afunction of the assumed cosmological model. For virtually any inputvalue of Omega(0) in the range 0.01-5.00, there is a reasonablyconsistent interpretation of the CfA survey such that the specifiedvalue of Omega(0) can be derived from the binary sample obtained underthat interpretation. A secondary result is that the higher the inputvalue of Omega(0), the broader the intrinsic distribution in M/L, andhence the less valid the assumption that light traces mass. High signal-to-noise ratio observations of H I in 243 galaxiesThe 21 cm spectral-line system of the Arecibo Observatory was used tomeasure neutral hydrogen emission from 243 faint galaxies. Most lie nearthe plane of the Local Supercluster. All observations reach anunsmoothed signal-to-noise ratio of at least 7.0; the average for theset is 23. The resulting data are used to estimate H I masses, systemicvelocities, and accurate profile widths at 20 percent, 25 percent, 50percent, and 80 percent of peak intensity levels. The widths are used tocalibrate directly the bias introduced by popular data-smoothingoperation. The data include observations of 65 objects with previouslyunknown redshifts. A search for environmental effects on the optical properties of galaxies in groupsEnvironmental density-related modifications of basic optical properties(luminosities, sizes, axial ratios, and colors) of galaxies belonging toGeller and Huchra's (1983) groups have been investigated. Remarkably, itis found that the broad maxima of the distributions of luminosities anddiameters of spirals and the whole corresponding distributions oflenticulars tend to move to lower values as one goes to groups of highcompactness, whereas the luminosity-diameter relationship of spiralstends to become flatter. No color and axial ratio differences betweengalaxies of high- and low-compactness groups have been detected. New central velocity dispersions for the bulges of 53 spiral and S0 galaxiesIt is pointed out that measurements of the central velocity dispersionsin the bulges of spiral and S0 galaxies have proved valuable in studiesof the comparative kinematics of bulges and elliptical galaxies. Thepresent investigation is concerned with new measurements conducted witha photon-counting Reticon system at a 1.5 m reflector and withobservations carried out with the aid of the intensified image dissectorscanner at a 2.1 m telescope. The determined velocity dispersions andredshifts are listed in two tables. A survey of galaxy redshifts. IV - The dataThe complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s. A catalog of hierarchical subclustering in the Turner-Gott groupsInformation on the substructure, to four levels of hierarchy, ispresented for the 103 groups listed by Turner and Gott (TG) in theircatalog of groups of galaxies. All galaxies brighter than Mpg= 14.0 in the region delta is 0 deg or greater and b(II) is 40 deg orgreater that have been assigned group memberships by TG are included.Also listed is the local environmental information for each of thegalaxies, giving the surface density enhancement beta in the galaxy'sneighborhood, calculated at 15 levels in the range beta = 4.6 to 10,000.
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# NodeJS server error while running two servers

I have two NodeJS directories with same files except that the main one is running on PORT 8080 and other on PORT 9000. I am getting the following error while running the second service:

TypeError [ERR_INVALID_ARG_VALUE]: The argument 'mode' must be a 32-bit unsigned integer or an octal string. Received '0o777'

I have defined PORT using

var port = process.env.PORT || 8080; //main one

var port = process.env.PORT || 9000; //second one in a different directory with same files

The error is thrown on this piece of code:

Redis.Promise.onPossiblyUnhandledRejection(function(error) {
error.command ? logger.error(error, {name: error.command.name, args: error.command.args}) : logger.error(error);
});

The same thing is working as expected in another system but my system throws this error at the terminal. I have searched for it but cannot find a possible solution. All I am doing is running node server.js in both directories. What can be the possible reason for this?

Source: AngularJS

format: plain


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# Math Help - triple integral

1. ## triple integral

triple integral( xy dxdydz)
through the quadrant of the unit sphere shell
x^2+y^2+z^2= 1

i m not sure about the upper limit of theta, phi, when changing variables.

i think, theta goes from 0 to pi
phi goes from 0 to half pi?

2. Originally Posted by szpengchao
triple integral( xy dxdydz)
through the quadrant of the unit sphere shell
x^2+y^2+z^2= 1

i m not sure about the upper limit of theta, phi, when changing variables.

i think, theta goes from 0 to pi
phi goes from 0 to half pi?
If you mean the first octant( where x,y,z are positive)

$\int_{0}^{\pi/2}\int_{0}^{\pi/2}\int_{0}^{1}\left( \rho\sin(\phi)\cos(\theta)\right) \left( \rho\sin(\phi)\sin(\theta)\right)\rho^2\sin(\phi)d \rho d\phi d\theta$


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Extermum points of the intersection between simplex of probability and hyperplanes - MathOverflow most recent 30 from http://mathoverflow.net 2013-05-23T02:03:18Z http://mathoverflow.net/feeds/question/77428 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/77428/extermum-points-of-the-intersection-between-simplex-of-probability-and-hyperplane Extermum points of the intersection between simplex of probability and hyperplanes Behrouz 2011-10-07T07:21:47Z 2011-10-07T09:00:08Z
Let $\Delta$ be a probability simplex in $\mathbb{R}^d$. Now let $p_1,\ldots,p_n$ be a set of probability vectors in $\Delta$ where $\operatorname{Rank} \operatorname{span}({p_1,\ldots,p_n})=r$. Let $A$ be the set of all possible linear (including but not limited to convex) combinations of $p_1,\ldots,p_n$. Can it be shown that the intersection of $A$ and $D$ is an $r-1$-dimensional polytope. In other word, do there exist linearly independent $q_1,\ldots, q_r \in D$ such that $A\cap D =\operatorname{conv}(q_1,\ldots,q_r)$.


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# How can I open very large files with good performance?

I have server log files that are several gigabytes in size (on Ubuntu). When I attempt to open them, the terminal locks up for a minute or so while the file is loaded into Vim. Is there a way to reduce this time, for example by setting Vim to load the file on demand, or by some other method?

• Why not use less? – Bernhard Feb 3 '15 at 20:33
• Do you intend to manipulate the files in any way, or do you just want to view them? – 200_success Feb 3 '15 at 20:33
• I would like to edit the files. – peter-b Feb 3 '15 at 20:33
• – wchargin Feb 3 '15 at 20:56
• Most likely I will get banned from the site forever but I have to say it: when it comes to work with huge files Emacs is the tool for the job. :-) – toro2k Feb 4 '15 at 15:09

vim -u NONE gargantuan.txt

If this is substantially faster, then you probably have syntax highlighting, folding, plugins, or something else going on that's taking up most of the time. Try turning stuff off in your vimrc (and disabling your plugins) until you find the culprit.

Also make sure to set ft= syn= and syntax off.

If this doesn't help, it's probably the case that you have very long lines that are causing the problem. Try set nowrap to turn line wrapping off.

• vim -U NONE -N gargantuan.txt will do the same thing while running vim in nocompatible which runs in "vi iMproved" mode instead of trying to be compatible with the old "vi" – ecerulm May 11 '17 at 8:37

Vim is the wrong tool for the job: you should use a pager like more or less.

If you insist on using an editor, try this example adapted from the Vim wiki:

augroup LargeFile
let g:large_file = 10485760 " 10MB

" Set options:
"   eventignore+=FileType (no syntax highlighting etc
"   assumes FileType always on)
"   noswapfile (save copy of file)
"   bufhidden=unload (save memory when other file is viewed)
"   undolevels=-1 (no undo possible)
\ let f=expand("<afile>") |
\ if getfsize(f) > g:large_file |
\ set eventignore+=FileType |
\ setlocal noswapfile bufhidden=unload buftype=nowrite undolevels=-1 |
\ else |
\ set eventignore-=FileType |
\ endif
augroup END

• Can less or more also make changes to my file? – Martin Tournoij Feb 3 '15 at 21:50
• They can't, of course. Logs are not meant to be edited. – romainl Feb 3 '15 at 21:59
• sed was invented for this purpose. You figure out which changes you want to make, expressed as substitutions, then run sed to perform them. This also works on streams (i.e. file content that has no end because it is being produced). – reinierpost Jun 1 '15 at 8:30
• I have aliased less, more and man to vimpager. github.com/rkitover/vimpager – Alex Kroll Jun 6 '15 at 8:16

The LargeFile.vim plugin is designed to make editing large files faster. See http://www.drchip.org/astronaut/vim/index.html#LARGEFILE .

From the page:

Allows much quicker editing of large files (default: 100MB+ are "large"), at the price of turning off events, undo, syntax highlighting, etc. Also available at vim.sf.net where you may rank it.

According to the manual, the plugin works just by having it installed. You can set the cutoff by changing g:LargeFile, to an integer number of MB, which it says defaults to 20MB (in contrast to the project description which says 100)

The plugin also provides commands :UnLarge, :Large and :Large! to disable, reenable, or force enable (for small files) respectively on the currently loaded file.

I have heard that turning off syntax highlighting can help:

:syntax off

• Having any kind of folding enabled also has a massive effect – craigp Feb 4 '15 at 7:38

Another pager you may like to try is most: http://www.jedsoft.org/most/

Also, rotate your logs and as this may contribute to less larger logs.


text:
# Isaac C API¶

The Isaac C API allows you to use Isaac SDK features without needing to fully integrate the Isaac SDK into your software stack. It also empowers you to build Isaac applications with languages other than C++.

The C API supports sending messages to and from Isaac using the “JSON & buffers” format. In this format, most of the high-level message data is stored in a JSON object, while large data blocks, such as images and tensors, are stored in byte buffers.

## Samples¶

Isaac SDK contains two sample applications that illustrate how to use the C API:

• //apps/tutorials/c_api/viewer.c
• //apps/tutorials/c_api/depth.c

These samples work with dummy images and publish/receive messages via the C API. When you run viewer.c, you can view the image in Sight.

Use the following commands to run the samples:

bazel run //apps/tutorials/c_api:c_api_viewer
bazel run //apps/tutorials/c_api:c_api_depth

## Starting and Stopping an Application¶

Every Isaac application that uses the C API requires a JSON app file; for example, the samples above have corresponding viewer.app.json and depth.app.json files. Use the application graph of the JSON app file to define nodes that you wish to communicate with using the C API.

To start an Isaac application, load the JSON file as follows:

isaac_handle_t app;
isaac_create_application("", "path/to/config.app.json", 0, 0, 0, 0, &app);
isaac_start_application(app);

To shut down the application, use the following:

isaac_stop_application(app);
isaac_destroy_application(&app);

## Publishing a Message to Isaac¶

Isaac uses Cap’n Proto messages internally; however, since this message format is not universally supported, the C API exposes message payloads as JSON. If the node receiving the message expects a Cap’n Proto message, you will need to enable message conversion to the Cap’n Proto format.

Follow these steps to publish a message to Isaac:

1. Create a new message as follows:

isaac_uuid_t uuid;
isaac_create_message(app, &uuid);
isaac_write_message_json(app, &uuid, &json);

2. Set the proto ID of the message and enable JSON-to-proto conversion as follows:

isaac_set_message_proto_id(app, &uuid, proto_id);
isaac_set_message_auto_convert(app, &uuid, isaac_message_type_proto);

The isaac_set_message_proto_id() call requires the proto ID of the message. To determine the proto ID of a message, add the message type to the //apps/tutorials/c_api:typeid application, then run the application via bazel run //apps/tutorials/c_api:typeid. The proto ID will be displayed at the terminal.

3. Publish the message to an Isaac application node using the isaac_publish_message() call. The message will be forwarded to the node as a Cap’n Proto message.

isaac_publish_message(app, "node_name", "component_name", "key", &uuid);

See //apps/tutorials/c_api/viewer.c for an example of message publishing.

## Receiving a Message from Isaac¶

To receive the most recent message from any of the nodes defined in the JSON app file, use the following call:

isaac_receive_latest_new_message(app, "node_name", "component_name", "key", &uuid);

The isaac_receive_latest_new_message() call returns either a “success” code (isaac_error_success) or a “no message available” code (isaac_error_no_message_available).

Get the contents of the message as follows:

isaac_const_json_t json = isaac_create_null_const_json();
isaac_get_message_json(app, &uuid, &json);

If the message source publishes messages using Cap’n Proto, the message is automatically converted to JSON.

As soon as you are finished processing the message, use the isaac_release_message() call, which allows Isaac to reclaim any resources being used for the message:

isaac_release_message(app, &uuid);

If you want to retain any message data, copy it before releasing the message.

See //apps/tutorials/c_api/depth.c for an example of receiving messages.

## Building the C API¶

Use the following command to build the C API and deploy it to a folder on your local machine:

./engine/build/deploy.sh -p //engine/alice/c_api:isaac_engine_c_api-pkg -d x86_64 -h localhost --deploy_path ~

When linking your code, you must provide paths to the shared libraries for the C API and “sight” module, which are located here:

• <deploy_path>/engine/alice/c_api/libisaac_c_api.so
• <deploy_path>/packages/sight/libsight_module.so

The following is a command-line example of compilation using GCC:

gcc c_api_example.c \
-L./engine/alice/c_api -lisaac_c_api \
-L./packages/sight -lsight_module \
-o c_api_example

export LD_LIBRARY_PATH=./engine/alice/c_api:./packages/sight:\$LD_LIBRARY_PATH

./c_api_example

## Locale Settings¶

The locale of Isaac applications is automatically set to en_US.UTF-8 to prevent decimal conversion errors when converting JSON messages to/from proto messages. Therefore, JSON files that are generated for communication with Isaac nodes must be compatible with the en_US.UTF-8 locale.

## Buffer Layout¶

A message proto with a buffer must store the index of the buffer containing the data. For example, the “dataBufferIndex” in ColorCameraProto is the index of the buffer that contains the image data.

### Image Buffers¶

Below is an illustration of a buffer for a 720p RGB image. Each (row, column) location contains information regarding a pixel. Isaac image buffers are in row-major order.

### Tensor Buffers¶

In a one-dimensional tensor, the elements are stacked in order:

A two-dimensional tensor is similar to the image buffer described above: Each RGB value can be represented as a tuple element. If the image was grayscale, each element would be a number instead. The first element on a 2D tensor buffer is indexed as (0,0), the second element as (0,1), etc.

Similarly, a three-dimensional tensor has the following order:

Where max_i is the maximum index in dimension “i”.

A 3D tensor can represent an RGB image, with each (row, column, channel) index pointing to a value from 0 to 255.

## Example Messages¶

Execute the following command to generate example JSON files in the /tmp folder:

bazel run apps/samples/proto_to_json

These JSON files, which are detailed below, correspond to common protos used in Isaac.

### ColorCameraProto¶

• Filename: color_camera_proto.json
• Proto description: ColorCameraProto
• Proto ID: 12905539496848989000

See the Image Buffers section above for an illustration of a two-dimensional buffer layout.

### RangeScanProto¶

• Filename: range_scan_proto.json
• Proto description: RangeScanProto
• Proto ID: 11901202900662173387

See the Tensor Buffers section above for an explanation of the buffer layout. In this case, there is one buffer for ranges and another buffer for intensities. In the example JSON, the buffer size is 16x8 because the vertical beam angle (theta) list has 16 members, while there are eight horizontal ray slices (associated with the phi angles).

### StateProto (messages::DifferentialBaseDynamics)¶

• Filename: differential_base_state_proto.json
• Proto description: StateProto
• Proto ID: 13177870757040999364

See the Tensor Buffers section above for an explanation of the buffer layout. In this case, the buffer is a 1x1x4 tensor that contains the following values:

1. Linear speed
2. Angular speed
3. Linear acceleration
4. Angular acceleration

### StateProto (messages::DifferentialBaseControl)¶

• Filename: differential_base_control_proto.json
• Proto description: StateProto
• Proto ID: 13177870757040999364

See the Tensor Buffers section above for an explanation of the buffer layout. In this case, the buffer is a 1x1x2 tensor that contains the following values:

1. Linear speed
2. Angular speed


text:
Limma weights, non-specific interactions
2
1
Entering edit mode
@andrewbirnberg-16677
Last seen 2.6 years ago

Hi all,

I am developing an analysis of protein microarray data and have found that limma performs very well in terms of identifying positive controls in the assay. Unfortunately, there are a large number of known, non-specific interactors that previous people have been identified in earlier experiments. For the pipeline I would like to down-weight, but not exclude, these proteins from the analysis. I have an idea, but I'm not sure if it's a good one:

The thought is to add a value to the intensity of a probe that depends on its average across past experiments. This would essentially maintain the variance while reducing the fold changes between groups for that probe. It kind of places a higher burden of proof on the that interaction for it to be real.

The problem is that I won't be seeing true fold changes anymore when I look at my output and that seems pretty bad. Does anyone out there have any other solutions to this sort of problem or can think of a way to moderate the t values by incorporating old data? Or is there some feature of limma/eBayes that could handle probe weights when calculating p-values?

Any thoughts would be appreciated!

Thanks, Andrew

limma nonspecific filtering weight • 492 views
0
Entering edit mode

It is unclear to me what you mean by a "non-specific interactor". Interacting with what? Non-specific to what? Are you saying that there are proteins on your array that always come up at DE even if they have no relationship to the treatment conditions?

0
Entering edit mode

Sorry for my delay in responding. The array is a functional protein array and interactions with the "prey" (proteins printed on the array) are detected by an antibody to the "bait" (what was put on the array). A non-specific interaction would be caused by "stickiness" of the prey. In general, we would expect this to be roughly independent of treatment conditions, which as I believe you're hinting, should prevent this from coming up as DE in the analysis. Unfortunately, I am told by the people doing the assay that it doesn't work as cleanly as this and there are cases where the sticky proteins are somewhat unstable and do not react identically across arrays, so might appear to be specific interactions when they are merely acting badly on a particular array.

I guess one way to say this might be that sticky proteins have a higher than expected variance as compared to other proteins at the same signal intensity. Not sure if this makes sense to people with more experience in this area of statistics, but it's how I'm thinking about it at the moment.

Based on this idea, another way to handle this situation might be to use all available prior arrays when calling lmFit by adding a "background" condition to the design matrix, which is only there to provide more information when calculating and shrinking variances. Then we would get the benefit of hindsight but still only calculate the contrasts we care about based on the current experiment's arrays.

Is this reasonable?

Thanks!

1
Entering edit mode

Yes, you understood what I was hinting at. Adding background arrays can be useful in some circumstances but is probably unnecessary. I'll write short answer.

3
Entering edit mode
Aaron Lun ★ 27k
@alun
Last seen 18 hours ago
The city by the bay

The main problem here is that it's hard to convert a vague sense of "I don't like these proteins" into a concrete, quantitative weight. You say that you want to downweight the problematic interactors, but by how much? What does it mean to be twice as problematic? How many angels dance on the head of a pin?

Now let's consider your proposed approach. It seems that you're proposing to add a constant value - dependent on the average intensity of the probe from past experiments - to all observations for a probe. If this is done on the log-scale, then it will have no effect on anything (trend-based shrinkage aside), as the added value will cancel out when computing variances or log-fold changes. If this is done on the raw scale, then you're adding an arbitrary pseudo-count that will affect both the log-fold changes and variances of the log-values - not good for empirical Bayes shrinkage. More generally, there is no sound rationale for adding the average intensity. Why not half the average? Or the square root of the average? Or any number I might pull out of thin air?

The better approach is to make use of the definition of these problematic interactors. You say that these were identified as being non-specific in previous experiments. If this is non-specific DE, presumably you have log-fold changes for these proteins from previous experiments as well. This means you can test for changes in expression beyond this non-specific log-fold change using the treat function. Some testing suggests that lfc can support numeric vector inputs, so you can give a different lfc per gene. If the log-fold changes are larger than what would be expected due to non-specific activity, then there's probably a genuine change in expression.

Or you could take the safe route and just discard the problematic interactors. This would be my preferred approach if there's not too many of them. Why take the risk of reporting them when they're known to be non-specific? I know my collaborators would be pretty skeptical.

1
Entering edit mode

I agree, I would be making some very arbitrary choices here that could affect the analysis is unpredictable ways. I really like the idea of using a vector argument to lfc. I will play around with this. Removing the problematic interactors wouldn't work in our case since there may still be some biological rationale even for non-specific interactions having some importance. My favorite idea, but which I am not really sure how to build, is a probabilistic graphical model that spits out a probability of differential interaction and is able to take advantage of prior data. There are a couple of papers out there on hierarchical bayesian models for DE, but nothing I've found where it comes to "informative" priors.

2
Entering edit mode
@gordon-smyth
Last seen 30 minutes ago
WEHI, Melbourne, Australia

From your description, it sounds like you are simply worried about probes with large variances. limma already downweights probes with large variances. Belinda Phipson and I have even written a paper specifically about how to deal with probes that have particularly large variances (which we call "hypervariable" genes):

Robust hyperparameter estimation protects against hypervariable genes and improves power to detect differential expression

and have implemented a method for dealing with them efficiently through the limma empirical Bayes procedure. To activate this strategy, specify robust=TRUE when running eBayes() or treat().

So limma already does what you want. It will generally deal with hypervariable probes very sensibly, requiring them to show a much larger fold change than other genes before they are counted as DE.

If you have prior data that truly represents the variability of the different probes, then you could consider adding that to your experimental design and analyse it at the same time as you data of interest. That does assume however that the probes will continue to have the same underlying variances in the new experiment as in the old, and I think that it is a very strong assumption. I think this will usually be unnecessary and a straightforward analysis will be enough. Generally speaking, your attempts to micro-manage the process will just get in the way of limma doing its job.


text:
# How to fit an exponential equation of the form $Y = A + Be^{CX}$ to data

I need some assistance with a nonlinear adjust. I am trying to make a mathematical model that describes the rate of silicic acid escaping from an underwater sediment. For theoretical reasons, the equation resulting from the nonlinear regression must be exponential and have the form $Y = A + Be^{CX}$, in which $A$, $B$ and $C$ are constants, $X$ is an independent predictor (time) and $Y$ is a dependent variable (concentration). I lack but the basic understanding of statistical software, so I have just tried to make it on Excel. The problem is that there I can only adjust my data to equations like $Y = Ae^{Bx}$, that are without a constant. I know for sure that R with a specific package will work just fine for this problem, but I cannot find any tutorials to orientate me. I guess that there is a really easy answer for this almost trivial question, but for now it is eluding me. Thank you very much for your time and help!


text:
mersenneforum.org Peak Oil
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2009-09-22, 17:54   #23
cheesehead

"Richard B. Woods"
Aug 2002
Wisconsin USA

1E0C16 Posts

Here's a blog entry from The Oil Drum: Europe about the reasons for the shape of the Hubbert curve --

"Mind-sized Hubbert"

http://europe.theoildrum.com/node/5731

Quote:
 The bell shaped Hubbert curve is commonly observed when a non renewable, or slowly renewable, resource is exploited in a free market. But what is the origin of the curve? Ugo Bardi and Alessandro Lavacchi have recently published a simple "mind sized" model of the Hubbert behavior in "Energies" . ... Have you ever tried to tell a politician about peak oil? If you did, you know what happens. Supposing that he/she pays any attention to you, you'll immediately face at least two typical objections: if there is still oil underground, what is the problem? If the price is high enough, why should production decline? It is not easy to answer these questions in the 30 seconds which are the typical attention span of a politician. Failing to do that will make you look like a representative of one of those millenarian sects eagerly waiting for the end of the world. And the problem is not just with politicians; try to explain peak oil to your mother or to an economist. It is not easy. ... there are plenty of intelligent people out there who are perfectly able to understand the concept. The problem is how do we explain it to them. And, if we have to explain it, we must understand it first. What is, exactly, that causes production peaks for oil and for other non renewable resources? . . . "Mind sized" is a term invented by Seymour Papert, the creator of the "logo" programming language. He said that complex problems can always be broken into mind-sized blocks, and so can be grasped by the human mind. Indeed, most of us (including politicians) tend to take decisions based on the way we understand what's going on and our understanding can't be but mind sized. In addition, we tend to ignore what we don't understand. That may be one of the reasons why peak oil is so commonly ignored by politicians and decision makers. . . . But we had started with the idea of explaining the Hubbert curve to a politician; so, let me summarize the main assumptions of this "mind sized" model. ... 1. There exists a non renewable or slowly renewable resource which is limited in amount and "graded" in costs of extraction/production. 2. People will extract/produce first the low cost resource and will re-invest an approximately constant fraction of their profits in more facilities for extraction/production. This is the positive feedback that generates the rapid initial growth of the curve. 3. As the resource is consumed, increasing costs of production reduce profits and - as a consequence - investments in extraction/production. This is the negative feedback that generates the decline. When these three assumptions are described by two coupled equations, they generate a nearly symmetrical, bell shaped, curve. Political, technological and market factors may modify the behavior of the system. However, since the curve has been often observed in historical cases, we can conclude that these three assumptions are sufficient at least for accounting for the main tendency of this kind of system.

 2009-09-22, 18:27 #24 cheesehead     "Richard B. Woods" Aug 2002 Wisconsin USA 769210 Posts "Peak Oil" should be understood to mean "peak (oil + natural gas)" IMO. It's true that crude oil contains raw ingredients for many more products than natural gas contains, but when the main uses are just to burn them as fuel, they should be considered together for"peak" purposes. There's recently been a big* increase in estimated recoverable natural gas reserves within the U.S. (Note "recoverable". This reservoir of natural gas has long been known -- it just wasn't technically feasible to produce it, until recently.) "Rediscovering Natural Gas By Hitting Rock Bottom" http://www.npr.org/templates/story/s...35&ft=1&f=1025 "Glenn Thompson: There is a natural gas gold mine under our feet" http://www.washingtonexaminer.com/op...-59820907.html There's environmental controversy about pollution from shale gas production. However, unlike the case of shale oil -- where large amounts of water are needed in the process of extracting the oil from the shale, and the oil shale is concentrated in our western semiarid regions -- with shale gas the main concern is that there will be leakage from wells or fractured rock into now-clean water aquifers. "Water quality worries could slow shale drilling" http://www.reuters.com/article/GCA-G...58054Z20090901 "Great Lakes Directional Drilling Ban Should Be Lifted" http://www.mackinac.org/article.aspx?ID=9712 - - - Note: "big*" -- but not big enough to shift the occurrence of peak oil+gas by more than, say, a year. Last fiddled with by cheesehead on 2009-09-22 at 18:42
2009-11-09, 23:09   #25
ewmayer
2ω=0

Sep 2002
República de California

2×5,813 Posts
Whistleblower: IEA Inflates Oil Data to Stem Panic

Whistleblower Says IEA Inflating Oil Resource Data to Avoid Panic
Quote:
 The world is much closer to running out of oil than official estimates admit, according to a whistleblower at the International Energy Agency who claims it has been deliberately underplaying a looming shortage for fear of triggering panic buying. The senior official claims the US has played an influential role in encouraging the watchdog to underplay the rate of decline from existing oil fields while overplaying the chances of finding new reserves. The allegations raise serious questions about the accuracy of the organisation's latest World Energy Outlook on oil demand and supply to be published tomorrow – which is used by the British and many other governments to help guide their wider energy and climate change policies. In particular they question the prediction in the last World Economic Outlook, believed to be repeated again this year, that oil production can be raised from its current level of 83m barrels a day to 105m barrels. External critics have frequently argued that this cannot be substantiated by firm evidence and say the world has already passed its peak in oil production. Now the "peak oil" theory is gaining support at the heart of the global energy establishment. "The IEA in 2005 was predicting oil supplies could rise as high as 120m barrels a day by 2030 although it was forced to reduce this gradually to 116m and then 105m last year," said the IEA source, who was unwilling to be identified for fear of reprisals inside the industry. "The 120m figure always was nonsense but even today's number is much higher than can be justified and the IEA knows this. "Many inside the organisation believe that maintaining oil supplies at even 90m to 95m barrels a day would be impossible but there are fears that panic could spread on the financial markets if the figures were brought down further. And the Americans fear the end of oil supremacy because it would threaten their power over access to oil resources," he added. A second senior IEA source, who has now left but was also unwilling to give his name, said a key rule at the organisation was that it was "imperative not to anger the Americans" but the fact was that there was not as much oil in the world as had been admitted. "We have [already] entered the 'peak oil' zone. I think that the situation is really bad," he added.
My Comment: Just imagine what a return to $150/barrel oil would do to the [alleged] infant economic recovery in the U.S. and around the world. Oil more than doubling (in$US terms) since last winters post-bubble-pop lows already means that gasoline currently is 20% more expensive in the U.S. that it was at this time last year.

2009-11-11, 00:35   #26
cheesehead

"Richard B. Woods"
Aug 2002
Wisconsin USA

22·3·641 Posts

Quote:
 Originally Posted by cheesehead with shale gas the main concern is that there will be leakage from wells or fractured rock into now-clean water aquifers.
... and the leakage isn't necessarily only the natural gas from the shale ... There's also the secret-formula mix injected along with water and sand during hydraulic fracturing:

"Pennsylvania lawsuit says drilling polluted water"

http://news.yahoo.com/s/nm/20091109/..._fracking_suit

Quote:
 AVELLA, Pennsylvania (Reuters) – A Pennsylvania landowner is suing an energy company for polluting his soil and water in an attempt to link a natural gas drilling technique with environmental contamination. George Zimmermann, the owner of 480 acres in Washington County, southwest Pennsylvania, says Atlas Energy Inc. ruined his land with toxic chemicals used in or released there by hydraulic fracturing. Water tests at three locations by gas wells on Zimmermann's property -- one is 1,500 feet from his home -- found seven potentially carcinogenic chemicals above "screening levels" set by the U.S. Environmental Protection Agency as warranting further investigation. . . . If Zimmermann wins his case, it would be the first in America to prove that hydraulic fracturing causes water contamination. Such a finding could slow the development and use of cleaner-burning natural gas that would reduce American dependence on overseas energy. PERFECT BASELINE TESTS Baseline tests on Zimmermann's water a year before drilling began were "perfect," he said. In June, water tests found arsenic at 2,600 times acceptable levels, benzene at 44 times above limits and naphthalene five times the federal standard. Soil samples detected mercury and selenium above official limits, as well as ethylbenzene, a chemical used in drilling, and trichloroethene, a naturally occurring but toxic chemical that can be brought to the surface by gas drilling. . . .
The oil industry has repeatedly demonstrated that it has to be legally forced to clean up its wells and operations, just as other industries have to be legally forced to clean themselves up.

- - -

It's a lot easier to keep one's environment clean by reducing the use of hydrocarbons than it is to clean up after hydrocarbons are brought up out of the ground and used.

Last fiddled with by cheesehead on 2009-11-11 at 00:40

2009-11-11, 00:48   #27
cheesehead

"Richard B. Woods"
Aug 2002
Wisconsin USA

22×3×641 Posts

Quote:
 Originally Posted by ewmayer
It's sort of a Ponzi scheme in which many of the OPEC countries inflate estimates in order to portray a smooth future, but can't get enough new discoveries to prop up their figures. Eventually the faltering production forces some revelation of truth. Bernie Madoff may have his title of world's biggest Ponzi-er usurped long before his prison term runs out.

Quote:
 My Comment: Just imagine what a return to $150/barrel oil would do to the [alleged] infant economic recovery in the U.S. and around the world. The sooner there's a slap of reality, the better for us all in the long run. As the current US TV commercial for some acid-reducer has it: "It's simple, mister. Do you want it to hurt now, or hurt later?" Last fiddled with by cheesehead on 2009-11-11 at 00:55 2009-11-12, 21:13 #28 ewmayer 2ω=0 Sep 2002 República de California 1162610 Posts Goldman’s Global Oil Scam Goldman’s Global Oil Scam Passes the 50 Madoff Mark Quote: $2.5 Trillion - That’s the size of of the global oil scam. It’s a number so large that, to put it in perspective, we will now begin measuring the damage done to the global economy in "Madoff Units" ($50Bn rip-offs). That’s right -$2.5Tn is 50 TIMES the amount of money that Bernie Madoff scammed from investors in his lifetime, yet it is also LESS than the MONTHLY EXCESS price the global population is being manipulated into paying for a barrel of oil. Goldman Sachs, Morgan Stanley, BP, TOT, Shell, DB and Societe General founded the Intercontinental Exchange in 2000. ICE is an online commodities and futures marketplace. It is outside the US and operates free from the constraints of US laws. The exchange was set up to facilitate "dark pool" trading in the commodities markets. Billions of dollars are being placed on oil futures contracts at the ICE and the beauty of this scam is that they NEVER take delivery, per se. They just ratchet up the price with leveraged speculation using your TARP money. This year alone they ratcheted up the global cost of oil from $40 to$80 per barrel. A Congressional investigation into energy trading in 2003 discovered that ICE was being used to facilitate "round-trip" trades. Round-trip” trades occur when one firm sells energy to another and then the second firm simultaneously sells the same amount of energy back to the first company at exactly the same price. No commodity ever changes hands. But when done on an exchange, these transactions send a price signal to the market ... Over the course of an average month at the NYMEX, 5 BILLION barrels of oil will be traded, with a fee being collected on every single transaction which is ultimately passed down to US consumers, yet less than 40M barrels will actually be delivered. That is just 8 tenths of 1 percent of actual demand for the product that is being traded - 99.2% of the oil transaction fees being paid by the American people do nothing more than create fees for the traders and record profits and bonuses for the trading firms!
My Comment: Note that Goldman et al appear to be setting up a similar mass-scale fraud related to trading of carbon credits on the Chicago Climate Exchange. Neat trick ... that way theyll make money by inflating oil prices, and also make money by inflating the cost of "going green".

2009-11-12, 21:56   #29
cheesehead

"Richard B. Woods"
Aug 2002
Wisconsin USA

1E0C16 Posts

Quote:
 Originally Posted by ewmayer Goldman’s Global Oil Scam Passes the 50 Madoff Mark My Comment: Note that Goldman et al appear to be setting up a similar mass-scale fraud related to trading of carbon credits on the Chicago Climate Exchange. Neat trick ... that way they`ll make money by inflating oil prices, and also make money by inflating the cost of "going green".
The oil scam smells like Enron.

2010-03-24, 00:40   #30
cheesehead

"Richard B. Woods"
Aug 2002
Wisconsin USA

22·3·641 Posts

"Oil Production to Peak in 2014, Kuwaiti Scientists Predict"

http://www.livescience.com/environme...ak-100312.html
Quote:
 . . . Updated model The scientists from Kuwait University and the Kuwait Oil Company adopted a newer approach by including many Hubbert production cycles, or bell-shaped curves showing the rise and fall of a non-recyclable resource. Earlier models typically assumed just one production cycle, despite the fact that most oil-producing nations have historically experienced more of a rollercoaster ride in production. Such production cycles reflect the influence of new technological innovations in the oil industry, government regulations, economic conditions and political events. The factors include the discovery of new oil deposits, the recent economic recession and the rise of renewable energy. . . . The new model The Kuwaiti study created its world model for peak oil based on 47 individual models for each major oil-producing nation. It also took a separate look at the Organization of the Petroleum Exporting Countries (OPEC), which includes nations that control about 35 percent of the world's oil reserves. . . .

 2010-03-24, 01:10 #31 CRGreathouse     Aug 2006 32×5×7×19 Posts Cheesehead, those last two posts seem contradictory -- or at least it seems that accepting both is contradictory. If oil is running out soon (peaking 2014 and dwindling thereafter, while population and industrialization increase) then price increases seem reasonable and not like a Ponzi scheme. I accept the latter post and reject the former. Indeed, I thought the world was already past its peak production of oil. (There's plenty of oil left in the ground, but it's hard -- and expensive -- to harvest most of it.) So I was surprised when oil prices dropped so sharply (notwithstanding the economic downturn) and unsurprised at their present return. Do you accept both? If so, would you explain?
2010-03-24, 01:43   #32
cheesehead

"Richard B. Woods"
Aug 2002
Wisconsin USA

22·3·641 Posts

Quote:
 Originally Posted by CRGreathouse Cheesehead, those last two posts seem contradictory
My next-to-last post #29 was just a one-line comment, and I find it hard to believe you're taking that as contradictory to #30. Do you mean that #27 and #30 seem contradictory ... or what? Would you please quote the contradictions you're referring to?

Last fiddled with by cheesehead on 2010-03-24 at 01:45

2010-03-24, 01:50   #33
CRGreathouse

Aug 2006

32·5·7·19 Posts

Quote:
 Originally Posted by cheesehead My next-to-last post #29 was just a one-line comment, and I find it hard to believe you're taking that as contradictory to #30. Do you mean that #27 and #30 seem contradictory ... or what? Would you please quote the contradictions you're referring to?
I did mean that. Or at least, that accepting the premise of the article in #28 (responded to in #29) as well as the one in #30 are (near-) contradictory. So my question would be:
* Do you accept, as in #28 and #29, that the price of oil is being dramatically inflated?
* Do you accept, as in #30, that ready oil supplies are being quickly depleted?
* Regardless of the above answers, do you see a contradiction between these two?

Last fiddled with by CRGreathouse on 2010-03-24 at 01:50

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This is the eighth thread for the Polymath8b project to obtain new bounds for the quantity

$\displaystyle H_m := \liminf_{n \rightarrow\infty} (p_{n+m} - p_n),$

either for small values of ${m}$ (in particular ${m=1,2}$) or asymptotically as ${m \rightarrow \infty}$. The previous thread may be found here. The currently best known bounds on ${H_m}$ can be found at the wiki page.

The big news since the last thread is that we have managed to obtain the (sieve-theoretically) optimal bound of ${H_1 \leq 6}$ assuming the generalised Elliott-Halberstam conjecture (GEH), which pretty much closes off that part of the story. Unconditionally, our bound on ${H_1}$ is still ${H_1 \leq 270}$. This bound was obtained using the “vanilla” Maynard sieve, in which the cutoff ${F}$ was supported in the original simplex ${\{ t_1+\dots+t_k \leq 1\}}$, and only Bombieri-Vinogradov was used. In principle, we can enlarge the sieve support a little bit further now; for instance, we can enlarge to ${\{ t_1+\dots+t_k \leq \frac{k}{k-1} \}}$, but then have to shrink the J integrals to ${\{t_1+\dots+t_{k-1} \leq 1-\epsilon\}}$, provided that the marginals vanish for ${\{ t_1+\dots+t_{k-1} \geq 1+\epsilon \}}$. However, we do not yet know how to numerically work with these expanded problems.

Given the substantial progress made so far, it looks like we are close to the point where we should declare victory and write up the results (though we should take one last look to see if there is any room to improve the ${H_1 \leq 270}$ bounds). There is actually a fair bit to write up:

• Improvements to the Maynard sieve (pushing beyond the simplex, the epsilon trick, and pushing beyond the cube);
• Asymptotic bounds for ${M_k}$ and hence ${H_m}$;
• Explicit bounds for ${H_m, m \geq 2}$ (using the Polymath8a results)
• ${H_1 \leq 270}$;
• ${H_1 \leq 6}$ on GEH (and parity obstructions to any further improvement).

I will try to create a skeleton outline of such a paper in the Polymath8 Dropbox folder soon. It shouldn’t be nearly as big as the Polymath8a paper, but it will still be quite sizeable.