1,234 research outputs found

    Exercises to develop skill in map reading in grade four

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    Thesis (Ed.M.)--Boston Universit

    Evolution by Evaluation

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    This paper describes the process of formally evaluating an E-Learning system that has been in use for several years. Professional usability evaluation offers deeper insight into user behaviour and needs than accidental feedback collection or introspection by system developers. A first analysis of the evaluation samples shows satisfaction of users with the general design of the system but also dissatisfaction with certain aspects of navigation that would otherwise have escaped our attention. State of the art formal evaluation turned out to be instrumental in making an existing system considerably more user-friendly

    The 27-28 October 1986 FIRE IFO Cirrus Case Study: Cloud Optical Properties Determined by High Spectral Resolution Lidar

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    During the First ISCCP Region Experiment (FIRE) cirrus intensive field observation (IFO) the High Spectral Resolution Lidar was operated from a roof top site on the University of Wisconsin-Madison campus. Because the HSRL technique separately measures the molecular and cloud particle backscatter components of the lidar return, the optical thickness is determined independent of particle backscatter. This is accomplished by comparing the known molecular density distribution to the observed decrease in molecular backscatter signal with altitude. The particle to molecular backscatter ratio yields calibrated measurements of backscatter cross sections that can be plotted ro reveal cloud morphology without distortion due to attenuation. Changes in cloud particle size, shape, and phase affect the backscatter to extinction ratio (backscatter-phase function). The HSRL independently measures cloud particle backscatter phase function. This paper presents a quantitative analysis of the HSRL cirrus cloud data acquired over an approximate 33 hour period of continuous near zenith observations. Correlations between small scale wind structure and cirrus cloud morphology have been observed. These correlations can bias the range averaging inherent in wind profiling lidars of modest vertical resolution, leading to increased measurement errors at cirrus altitudes. Extended periods of low intensity backscatter were noted between more strongly organized cirrus cloud activity. Optical thicknesses ranging from 0.01-1.4, backscatter phase functions between 0.02-0.065 sr (exp -1) and backscatter cross sections spanning 4 orders of magnitude were observed. the altitude relationship between cloud top and bottom boundaries and the cloud optical center altitude was dependent on the type of formation observed Cirrus features were observed with characteristic wind drift estimated horizontal sizes of 5-400 km. The clouds frequently exhibited cellular structure with vertical to horizontal dimension ratios of 1:5-1:1

    Home Manufacture of Drugs: An Online Investigation and a Toxicological Reality Check of Online Discussions on Drug Chemistry

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    Emerging trends in market dynamics and the use of new psychoactive substances are both a public health concern and a complex regulatory issue. One novel area of investigation is the availability of homemade opioids, amphetamines and dissociatives, and the potential fueling of interest in clandestine home manufacture of drugs via the Internet. We illustrate here how online communal folk pharmacology of homemade drugs on drug website forums may actually inform home manufacture practices or contribute to the reduction of harms associated with this practice. Discrepancies between online information around purification and making homemade drugs safer, and the synthesis of the same substances in a proper laboratory environment, exist. Moderation and shutdown of synthesis queries and discussions online are grounded in drug websites adhering to harm-reduction principles by facilitating discussions around purification of homemade drugs only. Drug discussion forums should consider reevaluating their policies on chemistry discussions in aiming to reach people who cannot or will not refrain from cooking their own drugs with credible information that may contribute to reductions in the harms associated with this practice. © 2017 Taylor & Francis Group, LL

    Distinction of subtype-specific antibodies against European porcine influenza viruses by indirect ELISA based on recombinant hemagglutinin protein fragment-1

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    BACKGROUND: Serological investigations of swine influenza virus infections and epidemiological conclusions thereof are challenging due to the complex and regionally variable pattern of co-circulating viral subtypes and lineages and varying vaccination regimes. Detection of subtype-specific antibodies currently depends on hemagglutination inhibition (HI) assays which are difficult to standardize and unsuitable for large scale investigations. METHODS: The nucleocapsid protein (NP) and HA1 fragments of the hemagglutinin protein (HA) of five different lineages (H1N1av, H1N1pdm, H1pdmN2, H1N2, H3N2) of swine influenza viruses were bacterially expressed and used as diagnostic antigens in indirect ELISA. RESULTS: Proteins were co-translationally mono-biotinylated and refolded in vitro into an antigenically authentic conformation. Western blotting and indirect ELISA revealed highly subtype-specific antigenic characteristics of the recombinant HA1 proteins although some cross reactivity especially among antigens of the H1 subtype were evident. Discrimination of antibodies directed against four swine influenza virus subtypes co-circulating in Germany was feasible using the indirect ELISA format. CONCLUSIONS: Bacterially expressed recombinant NP and HA1 swine influenza virus proteins served as antigens in indirect ELISAs and provided an alternative to commercial blocking NP ELISA and HI assays concerning generic (NP-specific) and HA subtype-specific sero-diagnostics, respectively, on a herd basis

    La comunicazione politica nei manifesti della campagna elettorale 2008

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    Il presente lavoro si propone di prendere in esame i criteri comunicativi adottati dai principali partiti nei manifesti elettorali prodotti in occasione delle elezioni politiche del 2008. Dopo una breve parte propedeutica sulla comunicazione politica ed un excursus sulla storia del manifesto politico si procede ad analizzare dettagliatamente i manifesti elettorali dei principali partiti: Il Popolo della Libertà, Alleanza Nazionale, Lega Nord, La Destra, Partito Democratico, Italia dei Valori, Unione di Centro, Partito Socialista, La Sinistra, l’Arcobaleno. L’analisi si basa sui manifesti che è stato possibile rintracciare sui siti internet dei partiti e nella Rete in generale. I principali campi di indagine sono: il tipo di immagini scelte dai partiti a suffragio delle loro proposte politiche, la grafica, i colori e il lessico adottato per attirare l’attenzione dell’elettore e convincerlo ad orientare il suo voto in una determinata direzion
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