683 research outputs found

    Analysis Quality Dino Tour Travel Management Website Using WebQual 4.0

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    The rapid development of internet technology is getting a lot of benefits, especially in the use of the website. Therefore, an aspect of the website must meet the standards of quality websites. In this study, the quality of the Dino Tour Travel Management website is measured by using the WebQual method. WebQual is one method or technique of measuring the quality of a website based on the perception of the end user. This method is an extension of the widely used SERVQUAL prior to the measurement of service quality. From the analysis and the results of a questionnaire distributed to 23 respondents, it can be concluded that Dino Tour Travel Management website (pulautidungdino.com) meets a standard aspect of quality websites based WebQual 4.0. However, the low value of the acquisition for some questions, the manager of the website are advised to provide information that is more detailed and easy to understand

    The Host Galaxy of GRB980703 at Radio Wavelengths - a Nuclear Starburst in a ULIRG

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    We present radio observations of GRB980703 at 1.43, 4.86, and 8.46 GHz for the period of 350 to 1000 days after the burst. These radio data clearly indicate that there is a persistent source at the position of GRB980703 with a flux density of approximately 70 ÎŒ\muJy at 1.43 GHz, and a spectral index, ÎČ≈0.32\beta\approx 0.32, where FΜ∝Μ−ÎČF_\nu\propto \nu^{-\beta}. We show that emission from the afterglow of GRB980703 is expected to be one to two orders of magnitude fainter, and therefore cannot account for these observations. We interpret this persistent emission as coming from the host galaxy --- the first example of a gamma-ray burst (GRB) host detection at radio wavelengths. We show that emission from an AGN is unlikely, and find that it can be explained as a result of a star-formation rate (SFR) of massive stars (M>5M⊙_\odot) of 90 M⊙_\odot/yr, which gives a total SFR of ≈500\approx 500 M⊙_\odot/yr. Using the correlation between the radio and far-IR (FIR) luminosities of star-forming galaxies, we find that the host of GRB980703 is at the faint end of the class of Ultra Luminous Infrared Galaxies (ULIRGs), with L_{FIR}\sim few\times 10^{12} L⊙_\odot. From the radio measurements of the offset between the burst and the host, and the size of the host, we conclude that GRB980703 occurred near the center of the galaxy in a region of maximum star formation. A comparison of the properties of this galaxy with radio and optical surveys at a similar redshift (z≈1z\approx 1) reveals that the host of GRB980703 is an average star-forming galaxy. This result has significant implications for the potential use of a GRB-selected galaxy sample for the study of galaxies and the IGM at high redshifts.Comment: Submitted to Ap

    The weed species composition in a reed canary grass (Phalaris arundinacea L.) plantation for energy purposes depending on its age

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    The present experiment, carried out in nine production fields of reed canary grass (Phalaris arundinacea) grown for energy purposes, evaluated the effect of plantation age on the occurrence and species composition of weeds. The selected plantations were divided into 3 groups that were conventionally called “young” (1–2 years old), “middle-aged” (3–5 years old), and “older” plantations (6–8 years old). Regardless of plantation age, altogether 43 species were found in the experimental fields. Moreover, 6 species were common for all the plantations and were found in them regardless of plantation age. The least species, only 18, were found on the “young” plantations, almost twice more on the “older” ones (30 species), whereas the largest spectrum of species was found in the “middle-aged” plantations (33 species). In the “young” plantations, annual weeds were the most common, with the highest constancy and coverage index found for Chenopodium album, Matricaria maritima ssp. inodora and Echinochloa crus-galli. The greatest variation in species was found in the “middle-aged” plantations. However, only 4 species achieved the highest constancy and coverage index: Matricaria maritima ssp. inodora, Cirsium arvense, Poa trivialis and Taraxacum officinale. Furthermore, perennial weeds were found to be dominant in the “older” plantations. Within this group, Poa trivialis, Taraxacum officinale, Urtica dioica, Plantago maior, and Cirsium arvense had the highest constancy and coverage index

    Factors constraining extension workers effectiveness in improving horticultural production: a case study from West Timor, Indonesia

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    The Indonesian government and the government of Nusa Tenggara Timur recognise that horticulture is economically important and is expected to become the leading agribusiness sector to overcome poverty for farmers. Hence, in the last 20 years, the government of Nusa Tenggara Timur through various agribusiness projects has encouraged the planting of more than 18,490 hectares of vegetables and 82,010 hectares of fruit. The major producing areas of both are in the Kupang district and in the Timor Tengah Selatan. However, productivity is low. If production can be increased, on-farm income may also increase, but this is dependent upon Agricultural Extension Workers performing their roles more effectively. This study investigates the constraints that impede the ability of Agricultural Extension Workers to effectively perform their roles. The results suggest that while Agricultural Extension Workers are not performing their roles effectively there are a number of reasons for this, many of them beyond the control of Agricultural Extension Workers. While the Nusa Tenggara Timur province is supposedly following the Training and Visits model Agricultural Extension Workers receive very little training. Other major constraints identified include the constant restructuring of the Agricultural Department, poor remuneration, oppressive authority, inadequate infrastructure, unclear job direction, geographical condition, and bureaucracy. Unless these constraints are addressed, the system will remain unable to deliver the information and skills necessary for farmers to overcome poverty

    Abundance Profiles and Kinematics of Damped Lyman-alpha Absorbing Galaxies at z < 0.65

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    We present a spectroscopic study of six damped Lya absorption (DLA) systems at z<0.65, based on moderate-to-high resolution spectra of the galaxies responsible for the absorbers. Combining known metallicity measurements of the absorbers with known optical properties of the absorbing galaxies, we confirm that the low metal content of the DLA population can arise naturally as a combination of gas cross-section selection and metallicity gradients commonly observed in local disk galaxies. We also study the Tully-Fisher relation of the DLA-selected galaxies and find little detectable evidence for evolution in the disk population between z=0 and z~0.5. Additional results of our analysis are as follows. (1) The DLA galaxies exhibit a range of spectral properties, from post-starburst, to normal disks, and to starburst systems, supporting the idea that DLA galaxies are drawn from the typical field population. (2) Large rotating HI disks of radius 30 h^{-1} kpc and of dynamic mass M_dyn > 10^{11} h^{-1} M_sun appear to be common at intermediate redshifts. (3) Using an ensemble of six galaxy-DLA pairs, we derive an abundance profile that is characterized by a radial gradient of -0.041 +/- 0.012 dex per kiloparsec (or equivalently a scale length of 10.6 h^{-1} kpc) from galactic center to 30 h^{-1} kpc radius. (4) Adopting known N(HI) profiles of nearby galaxies and the best-fit radial gradient, we further derive an N(HI)-weighted mean metallicity _weighted = -0.50 +/- 0.07 for the DLA population over 100 random lines of sight, consistent with _weighted = -0.64 (-0.86, +0.40) observed for z~1 DLA systems from Prochaska et al. Our analysis demonstrates that the low metal content of DLA systems does not rule out the possibility that the DLA population trace the field galaxy population.Comment: 57 pages, 17 figures, to appear in the ApJ 20 February 2005 issue; a pdf version of the paper with full-resolution figures is available at http://falcon.mit.edu/~hchen/public/tmp/dlachem.pd

    Wide-Field Chandra X-Ray Observations of AGN in Abell 85 & Abell 754

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    To better understand the mechanism or mechanisms that lead to AGN activity today, we measure the X-ray AGN fraction in a new sample of nearby clusters and examine how it varies with galaxy properties, projected cluster-centric radius, and cluster velocity dispersion. We present new wide-field Chandra X-ray Observatory observations of Abell 85, Abell 754 and the background cluster Abell 89B out to their virial radii. Out of seventeen X-ray sources associated with galaxies in these clusters, we classify seven as X-ray AGN with L_{X,B} > 10^{41} erg/s. Only two of these would be classified as AGN based on their optical spectra. We combine these observations with archival data to create a sample of X-ray AGN from six z < 0.08 clusters and find that 3.4+1.1/-0.8% of M_R 10^{41} erg/s. We find that more X-ray AGN are detected in more luminous galaxies and attribute this to larger spheriods in more luminous galaxies and increased sensitivity to lower Eddington-rate accretion from black holes in those spheroids. At a given X-ray luminosity limit, more massive black holes can be accreting less efficiently, yet still be detected. If interactions between galaxies are the principal drivers of AGN activity, then the AGN fraction should be higher in lower velocity dispersion clusters and the outskirts of clusters. However, the tendency of the most massive and early-type galaxies to lie in the centers of the richest clusters could dilute such trends. While we find no variation in the AGN fraction with projected cluster-centric radius, we do find that the AGN fraction increases significantly from 2.6+1.0/-0.8% in rich clusters to 10.0+6.2/-4.3% in those with lower velocity dispersions.Comment: Accepted by Astrophysical Journal, 17 pages using emulateapj.cls, 10 B & W Figures (degraded): Full resolution paper available at http://www.astronomy.ohio-state.edu/~sivakoff/AGN/XAGN_A85_A754.pd

    A New Look At Carbon Abundances In Planetary Nebulae. III. DDDM1, IC 3568, IC4593, NGC 6210, NGC 6720, NGC 6826, & NGC 7009

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    This paper is the third in a series reporting on a study of carbon abundances in a carefully chosen sample of planetary nebulae representing a large range in progenitor mass and metallicity. We make use of the IUE Final Archive database containing consistently-reduced spectra to measure line strengths of C III] 1909 along with numerous other UV lines for the planetary nebulae DDDM1, IC 3568, IC 4593, NGC 6210, NGC 6720, NGC 6826, & NGC 7009. We combine the IUE data with line strengths from optical spectra obtained specifically to match the IUE slit positions as closely as possible, to determine values for the abundance ratios He/H, O/H, C/O, N/O, and Ne/O. The ratio of C III] 1909/C II 4267 is found to be effective for merging UV and optical spectra when He II 1640/4686 is unavailable. Our abundance determination method includes a 5-level program whose results are fine-tuned by corrections derived from detailed photoionization models constrained by the same set of emission lines. All objects appear to have subsolar levels of O/H, and all but one show N/O levels above solar. In addition, the seven planetary nebulae span a broad range in C/O values. We infer that many of our objects are matter bounded, and thus the standard ionization correction factor for N/O may be inappropriate for these PNe. Finally, we estimate C/O using both collisionally-excited and recombination lines associated with C+2 and find the well established result that abundances from recombination lines usually exceed those from collisionally-excited lines by several times.Comment: 36 pages, 7 tables, 2 figures, latex. Tables and figures supplied as two separate postscript files. Accepted for publication in Ap

    Star Formation in Emission-Line Galaxies Between Redshifts of 0.8 and 1.6

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    Optical spectra of 14 emission-line galaxies representative of the 1999 NICMOS parallel grism Ha survey of McCarthy et al. are presented. Of the 14, 9 have emission lines confirming the redshifts found in the grism survey. The higher resolution of our optical spectra improves the redshift accuracy by a factor of 5. The [O II]/Ha values of our sample are found to be more than two times lower than expected from Jansen et al. This [O II]/Ha ratio discrepancy is most likely explained by additional reddening in our Ha-selected sample [on average, as much as an extra E(B-V) = 0.6], as well as to a possible stronger dependence of the [O II]/Ha ratio on galaxy luminosity than is found in local galaxies. The result is that star formation rates (SFRs) calculated from [O II]3727 emission, uncorrected for extinction, are found to be on average 4 +/- 2 times lower than the SFRs calculated from Ha emission. Classification of emission-line galaxies as starburst or Seyfert galaxies based on comparison of the ratios [O II]/Hb and [Ne III]3869/Hb is discussed. New Seyfert 1 diagnostics using the Ha line luminosity, H-band absolute magnitude, and Ha equivalent widths are also presented. One galaxy is classified as a Seyfert 1 based on its broad emission lines, implying a comoving number density for Seyfert 1s of 2.5{+5.9, -2.1} times 10^{-5} Mpc^{-3}. This commoving number density is a factor of 2.4{+5.5,-2.0} times higher than estimated by other surveys.Comment: 51 pages, 18 figures; Accepted for publication in the Astrophysical Journal; Revised version with minor changes and an additional reference which gives further support to our conclusion

    Retinal Architecture in ​\u3cem\u3eRGS9-\u3c/em\u3e and ​\u3cem\u3eR9AP\u3c/em\u3e-Associated Retinal Dysfunction (Bradyopsia)

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    Purpose To characterize photoreceptor structure and mosaic integrity in subjects with RGS9- and R9AP-associated retinal dysfunction (bradyopsia) and compare to previous observations in other cone dysfunction disorders such as oligocone trichromacy. Design Observational case series. Methods setting: Moorfields Eye Hospital (United Kingdom) and Medical College Wisconsin (USA). study population: Six eyes of 3 subjects with disease-causing variants in RGS9 or R9AP. main outcome measures: Detailed retinal imaging using spectral-domain optical coherence tomography and confocal adaptive-optics scanning light ophthalmoscopy. Results Cone density at 100 ÎŒm from foveal center ranged from 123 132 cones/mm2to 140 013 cones/mm2. Cone density ranged from 30 573 to 34 876 cones/mm2 by 600 ÎŒm from center and from 15 987 to 16,253 cones/mm2 by 1400 ÎŒm from center, in keeping with data from normal subjects. Adaptive-optics imaging identified a small, focal hyporeflective lesion at the foveal center in both eyes of the subject with RGS9-associated disease, corresponding to a discrete outer retinal defect also observed on spectral-domain optical coherence tomography; however, the photoreceptor mosaic remained intact at all other observed eccentricities. Conclusions Bradyopsia and oligocone trichromacy share common clinical symptoms and cannot be discerned on standard clinical findings alone. Adaptive-optics imaging previously demonstrated a sparse mosaic of normal wave-guiding cones remaining at the fovea, with no visible structure outside the central fovea in oligocone trichromacy. In contrast, the subjects presented in this study with molecularly confirmed bradyopsia had a relatively intact and structurally normal photoreceptor mosaic, allowing the distinction between these disorders based on the cellular phenotype and suggesting different pathomechanisms

    Tuberculosis in a shopping centre, Portugal, 2004-5

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    Genotyping enables to confirm or exclude a tuberculosis (TB) cluster. Excluding the link between cases is particularly important in countries with intermediate/high incidence of TB where the emergence of several TB cases in a particular location in space or time (higher than the expected) could be explained by chance alone. During 2004 and 2005, five TB cases occurred in five shops of a Portuguese shopping centre which employed a total of about 1000 workers. After an epidemiological survey, 52 close contacts were identified and screened. Latent tuberculosis infection was diagnosed in 10 contacts (eight family members and two work colleagues of cases). Genotyping of the Mycobacterium tuberculosis isolates revealed no link between the cases. For this reason no screening of all staff of the shopping centre was carried out. However, close contacts (52) and all fellow workers (1000) were kept under surveillance for two years, and no additional cases were diagnosed. The present analysis demonstrates that the exclusion of a chain of ongoing transmission by genotyping for the investigation of a cluster is cost-effective from the perspective of the public health service, because it allows to avoid unnecessary large scale screening operation and instead to direct resources to more effective measures of TB control.info:eu-repo/semantics/publishedVersio
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