422 research outputs found

    Analytic frameworks for assessing dialogic argumentation in online learning environments

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    Over the last decade, researchers have developed sophisticated online learning environments to support students engaging in argumentation. This review first considers the range of functionalities incorporated within these online environments. The review then presents five categories of analytic frameworks focusing on (1) formal argumentation structure, (2) normative quality, (3) nature and function of contributions within the dialog, (4) epistemic nature of reasoning, and (5) patterns and trajectories of participant interaction. Example analytic frameworks from each category are presented in detail rich enough to illustrate their nature and structure. This rich detail is intended to facilitate researchers’ identification of possible frameworks to draw upon in developing or adopting analytic methods for their own work. Each framework is applied to a shared segment of student dialog to facilitate this illustration and comparison process. Synthetic discussions of each category consider the frameworks in light of the underlying theoretical perspectives on argumentation, pedagogical goals, and online environmental structures. Ultimately the review underscores the diversity of perspectives represented in this research, the importance of clearly specifying theoretical and environmental commitments throughout the process of developing or adopting an analytic framework, and the role of analytic frameworks in the future development of online learning environments for argumentation

    Tuberculose in Nederland 2012

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    Op de gedrukte exemplaren van het rapport is het nummer 15000204. Het rapportnummer heeft een 0 te weinig; na versturing van de rapporten is dit pas opgemerktIn 2012 werden 958 patiënten met tuberculose gemeld aan het Nederlands Tuberculose Register (NTR). Dit komt overeen met een incidentie van tuberculose van 5,7 per 100.000 inwoners. Ten opzichte van 2011 en 2010 is de incidentie met respectievelijk vier procent en tien procent afgenomen. Sinds 2002 is het aantal tbc-patiënten in Nederland met 32% gedaald. In 2012 werd bij 53 procent van de gemelde patiënten longtuberculose geconstateerd. Het aantal patiënten met longtuberculose (pulmonale tbc) daalt sneller dan het aantal met extrapulmonale tbc (tuberculose buiten de longen). Het percentage extrapulmonale gevallen was het hoogste onder tbc-patiënten die in het buitenland zijn geboren. De meest voorkomende vorm van extrapulmonale tuberculose was tuberculose van de perifere lymfklieren. Achttien procent (177) van de tbc-patiënten in 2012 had sputumpositieve longtuberculose, de meest besmettelijke vorm van tuberculose. De incidentie van sputumpositieve longtuberculose in 2012 was 1,1 per 100.000 inwoners. Tuberculose komt in Nederland vaker voor bij personen geboren in het buitenland (eerstegeneratieallochtonen) en tweedegeneratieallochtonen. Bijna drie kwart van het aantal tbc-patiënten in 2012 was geboren in het buitenland (73%). Van de groep eerstegeneratieallochtonen met tuberculose in Nederland was de groep Somaliërs net als voorgaande jaren het grootste (170). Het percentage tbc-patiënten afkomstig uit Somalië was daarmee even groot als het percentage autochtone Nederlanders met tuberculose (18 procent), maar de incidentie onder Somaliërs in Nederland is bijna 500 maal hoger dan onder autochtone Nederlanders (respectievelijk 1,3 en 691 per 100.000 inwoners). Multiresistente tuberculose Het aantal patiënten met multiresistente tuberculose (MDR-tbc) in Nederland schommelt de laatste vijf jaar tussen tien en twintig patiënten; dat is 1-2% van het totaal aantal patiënten. In 2012 werden elf patiënten met multiresistente tuberculose gediagnosticeerd. Eén van de elf patiënten met mulitresistente tuberculose was afkomstig uit Nederland, de tien andere patiënten uit het buitenland. Resultaat van de behandeling Van alle in 2011 geregistreerde tbc-patiënten voltooide 87% de tbc-behandeling met succes. Bij nieuwe patiënten met longtuberculose was dit percentage iets lager (85%). Patiënten met multiresistente tuberculose voltooiden minder vaak de behandeling. Van de elf MDR-tbc-patiënten gediagnosticeerd in 2010 voltooiden zeven (64%) de behandeling met succes, één patiënt (9%) brak de behandeling voortijdig af, één patiënt zette de behandeling in het buitenland voort, één patiënt is overleden aan een andere oorzaak dan tuberculose en van één patiënt is het behandelresultaat (nog) niet bekend. Sterfte aan tuberculose Van de tbc-patiënten geregistreerd in het NTR in 2011 en 2012 overleden respectievelijk achttien (1,8%) en zes personen (0,6%) aan tuberculose. Patiënten met ernstige comorbiditeit hebben grotere kans op sterfte aan tuberculose. In 2012 overleed één persoon met diabetes, twee personen met een maligniteit en één persoon met nierinsufficiëntie aan tuberculose. Latente tbc-infectie (LTBI) In 2012 zijn 1.293 nieuwe gevallen van LTBI geregistreerd. Bij 855 personen werd de diagnose bij bron- en contactonderzoek vastgesteld. In 2011 startten in totaal 1.027 van de 1.297 personen (79%) een preventieve behandeling. Van hen voltooide 84% de LTBI-behandeling met succes. Delay Op grond van de gegevens in het NTR is de gemiddelde duur van het diagnostisch delay in de periode 2005-2012 niet toegenomen, hoewel bij illegalen, dak- en thuislozen, en drugs- en alcoholverslaafden wel aanwijzingen zijn voor een langer patient delay. Bij ruim een kwart van de patiënten die passief worden gevonden is wel sprake van een 'te lang' of 'ongunstig delay'. Voor doctor delay geldt hetzelfde: er is bij ruim een kwart van de patiënten die passief worden gevonden sprake van een 'te lang' of 'ongunstig delay'. Case finding In totaal 15% van alle tbc-patiënten werd in 2012 gevonden door actieve opsporing door de afdeling tbc-bestrijding van de GGD. Het percentage tbc-patiënten dat gevonden wordt door screening van risicogroepen zoals nieuwe immigranten, asielzoekers, drugsverslaafden en dak- en thuislozen neemt al langere tijd af. In de jaren 1993-1998 werd 14% van de tbc-patiënten gevonden door screening, maar in 2012 was dit nog maar 8%. Het percentage patiënten gevonden via bron- en contactonderzoek was in 2012 hetzelfde als in voorgaande jaren (7%). Tbc-patiënten met verminderde weerstand Het percentage tbc-patiënten met een co-infectie met hiv was 3% in 2012. Het percentage tbc-patiënten die op co-infectie met hiv werden getest nam toe van 28% in 2008 naar 49% in 2011, maar is in 2012gestagneerd (47%). Van patiënten uit risicogebieden zoals sub-Sahara Afrika was in 59% van de gevallen de hiv-status bekend. Het aantal tbc-patiënten die behandeld worden met TNF-alfaremmers neemt toe. In 2012 betrof het achttien (1,9%) patiënten. Transmissie en clustersurveillance Van de patiënten met kweekpositieve tuberculose clusterde de helft met een voorgaande patiënt. Bij een derde van de clusterende patiënten was sprake van recente clustering, een mogelijk gevolg van recente transmissie in Nederland. In 2012 vertoonden vier van de clusters een groei van meer dan vijf patiënten. De laatste jaren zijn er minder snelgroeiende clusters, een teken dat transmissie van M. tuberculosis in Nederland afneemt of dat de bestrijdingsmaatregelen effectief zijn.In 2012 958 cases of tuberculosis (TB) were reported to the Netherlands Tuberculosis Register (NTR). The incidence rate was 5.7 per 100,000 population. Since 2002 the number of TB patients in the Netherlands declined with 32%. In 2012 53% of the notified cases was diagnosed with pulmonary tuberculosis. Over the years the number of patients with extrapulmonary TB declined less than the number with pulmonary TB. The percentage extrapulmonary cases is highest among foreign-born TB patients. Tuberculosis of the extra thoracic lymph nodes is the most common site of disease in extrapulmonary cases. 18% (177) of all TB cases in 2012 was sputum-smear positive. The incidence rate of smear-positive pulmonary TB was 1.1 per 100,000 population. The majority of TB patients in the Netherlands was foreign-born (73%). As in previous years the largest population group with TB in 2012 was Somalian (170). The percentage of TB patients born in Somalia is in 2012 the same as the percentage native Dutch TB patients (18%). The incidence rate among people coming from Somalia is almost 500 times higher than the incidence rate of the native Dutch population (respectively 691 and 1.3 per 100,000 population). Multidrug-resistant tuberculosis In the last five years the number of patients with multidrug-resistant tuberculosis (MDR-TB) in the Netherlands varies between ten and twenty patients, 1-2% of the total number of TB patients. In 2012 eleven patients with MDR-TB were registered; ten were foreign-born. Treatment Outcome In 2011 87% of all TB patients completed treatment successfully. Of new cases with pulmonary TB 85% completed treatment successfully. Patients with MDR-TB completed treatment less often. Seven (64%) out of eleven MDR-TB-patients diagnosed in 2010 completed treatment successfully, one patient (9%) interrupted treatment, one patient continued treatment abroad, one patient died due to another cause than tuberculosis and of one patient treatment outcome is (still) unknown. TB-patients with co-morbidity or immune disorders The percentage of hiv-infected TB patients was 3% in 2012. The percentage TB patients tested for hiv increased from 28% in 2008 to 49% in 2011, but did not increase in 2012 (47%). Hiv-status was known in 59% of TB patients coming from sub-Saharan Africa, a hiv endemic area. The number of TB patients associated with TNF-alfa inhibitors treatment increases. In 2012 18 patients were registered (1.9%). Tuberculosis deaths Respectively 18 (1.8%) and 6 (0.6%) TB patients in 2011 and 2012 died due to tuberculosis. TB patients with serious co-morbidity have a higher risk of dying. In 2012 one person with diabetes, two persons with cancer and one person with renal insufficiency died due to tuberculosis. Respectively 20 (2.0%) and 20 (2.1%) TB patients in 2011 and 2012 died of other causes. Latent Tuberculosis Infection (LTBI) In 2012 1,293 new cases of LTBI were reported. 855 of these cases were detected through contact investigation. In 2011 1,027 of 1,297 cases (79%) started preventive treatment. Eighty-four percent of all persons with LTBI who received preventive treatment completed treatment successfully. Delay The mean length of the diagnostic delay over the years 2005-2012 did not increase, although undocumented TB patients, homeless TB patients, and drug and alcohol addicts with TB are associated with a longer patient delay. In more than a quarter of the passively detected cases a too long or 'unfavorable' patient delay was registered. This also applies to doctor delay; in more than a quarter of the passively detected cases a too long or 'unfavorable' delay was registered. Case finding Fifteen percent of all TB patients was detected by active case finding by the TB department of the Municipal Health Services. The percentage TB patients detected through screening of risk groups such as new immigrants, asylum seekers, drug addicts and homeless people has been decreasing for some time; in the years 1993-1998 14% of all TB patients was detected through screening, in 2012 only 8%. The number and percentage of cases found through contact investigation stayed more or less the same (7%). Transmission and cluster surveillance In 2012 50% of the cases with a positive culture belonged to a cluster. In one third of these cases recent clustering was registered, possibly as a result of recent transmission in the Netherlands. In 2012 four existing clusters showed growth of more than five patients. In the last few years there were no large outbreaks registered in the Netherlands

    Probing the Ionizing Continuum of Narrow-Line Seyfert 1 Galaxies. I.Observational Results

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    We present optical spectra and emission-line ratios of 12 Narrow-Line Seyfert 1 (NLS1) galaxies that we observed to study the ionizing EUV continuum. A common feature in the EUV continuum of active galactic nuclei is the big blue bump (BBB), generally associated with thermal accretion disk emission. While Galactic absorption prevents direct access to the EUV range, it can be mapped by measuring the strength of a variety of forbidden optical emission lines that respond to different EUV continuum regions. We find that narrow emission-line ratios involving [OII]3727, Hbeta, [OIII]5007, [OI]6300, Halpha,[NII]6583, and [SII]6716,6731 indicate no significant difference between NLS1s and Broad-Line Seyfert 1 (BLS1) galaxies, which suggests that the spectral energy distributions of their ionizing EUV - soft X-ray continua are similar. The relative strength of important forbidden high ionization lines like [NeV]3426 compared to HeII4686 and the relative strength of [FeX]6374 appear to show the same range as in BLS1 galaxies. However, a trend of weaker F([OI]6300)/F(Halpha) emission-line ratios is indicated for NLS1s compared to BLS1s. To recover the broad emission-line profiles we used Gaussian components. This approach indicates that the broad Hbeta profile can be well described with a broad component (FWHM = 3275 +- 800 km/s) and an intermediate broad component (FWHM = 1200 +- 300 km/s). The width of the broad component is in the typical range of normal BLS1s. The emission-line flux that is associated with the broad component in these NLS1s amounts to at least 60% of the total flux. Thus it dominates the total line flux, similar to BLS1 galaxies.Comment: 34 pages, 9 figures. accepted for publication in the Astrophys.Journa

    Subaru High-Dispersion Spectroscopy of Narrow-Line Region in the Seyfert Galaxy NGC 4151

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    We report on a study of forbidden emission-line spectrum of nearby Seyfert 1.5 galaxy NGC 4151 based on the high-resolution (R ~ 45,000) optical spectrum obtained by using the High Dispersion Spectrograph boarded on the Subaru Telescope. The profile parameters such as the emission-line widths, the velocity shifts from the recession velocity of the host galaxy, and the asymmetry indices, for emission lines including very faint ones such as [Ar IV]4712,4740 and [Fe VI]5631,5677 are investigated. Statistically significant correlations between the measured profile parameters and the critical densities of transitions are found while there are no meaningful correlations between the profile parameters and the ionization potentials of ions. By comparing the results with photoionization model calculations, we remark that a simple power-law distribution of the gas density which is independent of the radius from the nucleus cannot explain the observed correlation between the emission-line widths and the critical densities of the transitions. Taking the additional dense gas component expected to exist at the innermost of the narrow-line region into account, the observed correlations between the emission-line width and the critical density of the transitions can be understood since high-critical-density emission lines can arise at such relatively inner regions even if their ionization potentials are low. The observed correlation between the blueshift amounts of emission lines and the critical densities of the ions is also explained if such dense gas clouds located closer to the nucleus have larger outflowing velocities.Comment: 19 pages and 1 separate jpeg figure. Accepted for publication in A

    Сопоставительный анализ эффективности и надежности применения пластинчатых и кожухотрубных теплообменных аппаратов на ЗАО «Томский приборный завод»

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    Вследствие экономических санкций к России поставка импортного теплоэнергетического оборудования становится затруднительной. Поэтому требуется замена пластинчатых теплообменников на кожухотрубные, что подтверждает практическую значимость этой проблемы.Due to economic sanctions to Russia, the supply of imported heat and power equipment becomes difficult. Therefore, replacement of plate heat exchangers with shell-and-tube heat exchangers is required, which confirms the practical importance of this problem

    Extended High-Ionization Nuclear Emission-Line Region in the Seyfert Galaxy NGC 4051

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    We present an optical spectroscopic analysis of the well-known Seyfert galaxy NGC 4051. The high-ionization nuclear emission-line region (HINER) traced by [Fe X]6374 is found to be spatially extended to a radius of 3a rcseconds (150 pc) west and southwest from the nucleus; NGC 4051 is the third example which has an extended HINER. The nuclear spectrum shows that the flux of [Fe X]6374 is stronger than that of [Fe VII] 6087 in our observation. This property cannot be interpreted in terms of a simple one-zone photoionization model. In order to understand what happens in the nuclear region in NGC 4051, we investigate the physical condition of the nuclear emission-line region in detail using new photoionization models in which the following three emission-line components are taken into account; (1) optically thick, ionization-bounded clouds; (2) optically thin, matter-bounded clouds; and (3) a contamination component which emits Hα\alpha and Hβ\beta lines. Here the observed extended HINER is considered to be associated with the low-density, matter-bounded clouds. Candidates of the contamination component are either the broad-line region (BLR) or nuclear star forming regions or both. The complexity of the excitation condition found in NGC 4051 can be consistently understood if we take account of these contamination components.Comment: 16 pages, including figures. To Appear in the Astronomical Journal February 2000 Issu

    Chromosome‐level reference genome of the soursop (Annona muricata) : a new resource for Magnoliid research and tropical pomology

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    The flowering plant family Annonaceae includes important commercially grown tropical crops, but development of promising species is hindered by a lack of genomic resources to build breeding programs. Annonaceae are part of the magnoliids, an ancient lineage of angiosperms for which evolutionary relationships with other major clades remain unclear. To provide resources to breeders and evolutionary researchers, we report a chromosome-level genome assembly of the soursop (Annona muricata). We assembled the genome using 444.32 Gb of DNA sequences (676x sequencing depth) from PacBio and Illumina short-reads, in combination with 10x Genomics and Bionano data (v1). A total of 949 scaffolds were assembled to a final size of 656.77 Mb, with a scaffold N50 of 3.43 Mb (v1), and then further improved to seven pseudo-chromosomes using Hi-C sequencing data (v2; scaffold N50: 93.2 Mb, total size in chromosomes: 639.6 Mb). Heterozygosity was very low (0.06%), while repeat sequences accounted for 54.87% of the genome, and 23,375 protein-coding genes with an average of 4.79 exons per gene were annotated using de novo, RNA-seq and homology-based approaches. Reconstruction of the historical population size showed a slow continuous contraction, probably related to Cenozoic climate changes. The soursop is the first genome assembled in Annonaceae, supporting further studies of floral evolution in magnoliids, providing an essential resource for delineating relationships of ancient angiosperm lineages. Both genome-assisted improvement and conservation efforts will be strengthened by the availability of the soursop genome. As a community resource, this assembly will further strengthen the role of Annonaceae as model species for research on the ecology, evolution and domestication potential of tropical species in pomology and agroforestry

    On the nature of Seyfert galaxies with high [OIII]5007 blueshifts

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    We have studied the properties of Seyfert galaxies with high [OIII]5007 blueshifts (`blue outliers'), originally identified because of their strong deviation from the M_BH - sigma relation of normal, narrow-line Seyfert 1 (NLS1) and broad-line Seyfert 1 (BLS1) galaxies. These blue outliers turn out to be important test-beds for models of the narrow-line region (NLR), for mechanisms of driving large-scale outflows, for links between NLS1 galaxies and radio galaxies, and for orientation-dependent NLS1 models. We report the detection of a strong correlation of line blueshift with ionization potential in each galaxy, including the measurement of coronal lines with radial velocities up to 500--1000 km/s. All [OIII] blue outliers have narrow widths of their broad Balmer lines and high Eddington ratios. While the presence of non-shifted low-ionization lines signifies the presence of a classical outer quiescent NLR in blue outliers, we also report the absence of any second, non-blueshifted [OIII] component from a classical inner NLR. These results place tight constraints on NLR models. We favor a scenario in which the NLR clouds are entrained in a decelerating wind which explains the strong stratification and the absence of a zero-blueshift inner NLR of blue outliers. The origin of the wind remains speculative at this time (collimated radio plasma, thermal winds, radiatively accelerated clouds). It is perhaps linked to the high Eddington ratios of blue outliers. Similar, less powerful winds could be present in all Seyfert galaxies, but would generally only affect the coronal line region (CLR), or level off even before reaching the CLR. Similarities between blue outliers in NLS1 galaxies and (compact) radio sources are briefly discussed.Comment: ApJ in press (scheduled for June 20 issue); incl. 4 colour figures. This, and related paper showing that NLS1 galaxies follow the M-sigma relation based on [SII], is also available at http://www.xray.mpe.mpg.de/~skomossa
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