994 resultados para wholly online mode


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2-(2-Phenyl-1H-phenanthro-[9,10-d]imidazole-1-yl)-acetic acid (PPIA) and 2-(9-acridone)-acetic acid (AAA), two novel precolumn fluorescent derivatization reagents, have been developed and compared for analysis of primary aromatic amines by high performance liquid chromatographic fluorescence detection coupled with online mass spectrometric identification. PPIA and AAA react rapidly and smoothly with the aromatic amines on the basis of a condensation reaction using 1-ethyl-3-(3dimethylaminopropyl)-carbodiimide (EDC) as dehydrating catalyst to form stable derivatives with emission wavelengths at 380 and 440 nm, respectively. Taking six primary aromatic amines (aniline, 2-methylaniline, 2-methoxyaniline, 4-methylaniline, 4-chloroaniline, and 4-bromoaniline) as testing compounds, derivatization conditions such as coupling reagent, basic catalyst, reaction temperature and time, reaction solvent, and fluorescent labeling reagent concentration have also been investigated. With the better PPIA method, chromatographic separation of derivatized aromatic amines exhibited a good baseline resolution on an RP column. At the same time, by online mass spectrometric identification with atmospheric pressure chemical ionization (APCI) source in positive ion mode, the PPIA-labeled derivatives were characterized by easy-to-interpret mass spectra due to the prominent protonated molecular ion m/z [M + H](+) and specific fragment ions (MS/MS) m/z 335 and 295. The linear range is 24.41 fmol-200.0 pmol with correlation coefficients in the range of 0.9996-0.9999, and detection limits of PPIA-labeled aromatic amines are 0.12-0.21 nmol/L (S/N = 3). Method repeatability, precision, and recovery were evaluated and the results were excellent for the efficient HPLC analysis. The most important argument, however, was the high sensitivity and ease-of-handling of the PPIA method. Preliminary experiments with wastewater samples collected from the waterspout of a paper mill and its nearby soil where pollution with aromatic amines may be expected show that the method is highly validated with little interference in the chromatogram.

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A method for the determination of long and short chain free fatty acids (FFAs), using 1-[2-(ptoluenesulfonate)-ethyll-2-phenylimidazole-[4,5-f-9,10-phenanthrene (TSPP) as labeling reagent, has been developed. Identification of FFA derivatives was carried out by HPLC-MS with atmospheric pressure chemical ionization (APCI) in positive ion mode. Gradient elution on an Agilent Eclipse XDB-C-8 column gave good separation of the derivatives. Excellent linear responses were observed and good compositional data could be obtained from as little as 200 mg of bryophyte plants and soil samples. Facile TSPP derivatization coupled with HPLC-APCI-MS analysis allowed the development of a highly sensitive method for the quantitative analysis of trace level of FFAs from biological and natural environmental samples.

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The study of linear relationships is foundational for mathematics teaching and learning. However, students’ abilities connect different representations of linear relationships have proven to be challenging. In response, a computer-based instructional sequence was designed to support students’ understanding of the connections among representations. In this paper we report on the affordances of this dynamic mode of representation specifically for students with learning disabilities. We outline four results identified by teachers as they implemented the online lessons.

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In this paper the dependence of the power consumption of pneumatic conveyors upon conveyed materials, pipeline route and bore, and mode of flow has been examined. The findings are that, with different materials and modes of flow, not only is the amount of power consumed very different but it varies in different ways with pipe bore and routing. Additionally it has been found that, for any given conveying system, the choice of air mover also has a strong influence on the power requirement.

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Congenital Erythrocytosis (CE), or congenital polycythemia, represents a rare and heterogeneous clinical entity. It is caused by deregulated red blood cell production where erythrocyte overproduction results in elevated hemoglobin and hematocrit levels. Primary congenital familial erythrocytosis is associated with low erythropoietin (Epo) levels and results from mutations in the Epo receptor gene (EPOR). Secondary congenital erythrocytosis arises from conditions causing tissue hypoxia and results in increased Epo production. These include hemoglobin variants with increased affinity for oxygen (HBB, HBA mutations), decreased production of 2,3-bisphosphoglycerate due to BPGM mutations, or mutations in the genes involved in the hypoxia sensing pathway (VHL, EPAS1 and EGLN1). Depending on the affected gene, CE can be inherited either in an autosomal dominant or recessive mode, with sporadic cases arising de novo. Despite recent important discoveries in the molecular pathogenesis of CE, the molecular causes remain to be identified in about 70% of the patients. With the objective of collecting all the published and unpublished cases of CE the COST action MPN&MPNr-Euronet developed a comprehensive internet-based database focusing on the registration of clinical history, hematological, biochemical and molecular data (http://www.erythrocytosis.org/). In addition, unreported mutations are also curated in the corresponding Leiden Open Variation Database (LOVD). This article is protected by copyright. All rights reserved.

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Since July 2014, the Office for National Statistics has committed to a predominantly online 2021 UK Census. Item-level imputation will play an important role in adjusting the 2021 Census database. Research indicates that the internet may yield cleaner data than paper based capture and attract people with particular characteristics. Here, we provide preliminary results from research directed at understanding how we might manage these features in a 2021 UK Census imputation strategy. Our findings suggest that if using a donor-based imputation method, it may need to consider including response mode as a matching variable in the underlying imputation model.

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This study had three purposes related to the effective implem,entation and practice of computer-mediated online distance education (C-MODE) at the elementary level: (a) To identify a preliminary framework of criteria 'or guidelines for effective implementation and practice, (b) to identify areas ofC-MODE for which criteria or guidelines of effectiveness have not yet been developed, and (c) to develop an implementation and practice criteria questionnaire based on a review of the distance education literature, and to use the questionnaire in an exploratory survey of elementary C-MODE practitioners. Using the survey instrument, the beliefs and attitudes of 16 elementary C'- MODE practitioners about what constitutes effective implementation and practice principles were investigated. Respondents, who included both administrators and instructors, provided information about themselves and the program in which they worked. They rated 101 individual criteria statenlents on a 5 point Likert scale with a \. point range that included the values: 1 (Strongly Disagree), 2 (Disagree), 3 (Neutral or Undecided), 4 (Agree), 5 (Strongly Agree). Respondents also provided qualitative data by commenting on the individual statements, or suggesting other statements they considered important. Eighty-two different statements or guidelines related to the successful implementation and practice of computer-mediated online education at the elementary level were endorsed. Response to a small number of statements differed significantly by gender and years of experience. A new area for investigation, namely, the role ofparents, which has received little attention in the online distance education literature, emerged from the findings. The study also identified a number of other areas within an elementary context where additional research is necessary. These included: (a) differences in the factors that determine learning in a distance education setting and traditional settings, (b) elementary students' ability to function in an online setting, (c) the role and workload of instructors, (d) the importance of effective, timely communication with students and parents, and (e) the use of a variety of media.

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Immanuel Kant’s publicity maxim states that other-regarding actions are wrong if their maxim is not compatible with their being made public. This has the effect of forbidding dissent or rebellion against tyranny, since rebels cannot make their intentions and plans public. However, new internet technologies offer public speech from behind the “shield” of anonymity, allowing dissent to be public but preventing reprisals from tyrants. This thesis examines not only this possibility, but the value of internet-based discursive spaces for politics, their viability as a mode for political communication, and their implications for Classical and Enlightenment approaches to politics and intellectual virtue. Anonymous internet communications favour logos-based reasoning and discourse, which, in the liberal-democratic tradition, is preferable to phronesis and its attendant elitism and chauvinism. These technologies can open new vistas for liberal-democratic politics.

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Exocyclic DNA adducts produced by exogenous and endogenous compounds are emerging as potential tools to study a variety of human diseases and air pollution exposure. A highly sensitive method involving online reverse-phase high performance liquid chromatography with electrospray tandem mass spectrometry detection in the multiple reaction monitoring mode and employing stable isotope-labeled internal standards was developed for the simultaneous quantification of 1,N(2)-etheno-2`-deoxyguanosine (1,N(2)-epsilon dGuo) and 1,N(2)-propano-2`-deoxyguanosine (1,N(2)-propanodGuo) in DNA. This methodology permits direct online quantification of 2`-deoxyguanosine and ca. 500 amol of adducts in 100 mu g of hydrolyzed DNA M the same analysis. Using the newly developed technique, accurate determinations of 1,N(2)-etheno-2`-deoxyguanosine and 1,N2-propano-2`-deoxyguanosine levels in DNA extracts of human cultured cells (4.01 +/- 0.32 1,N(2)-epsilon dGuo/10(8) dGuo and 3.43 +/- 0.33 1,N(2)-propanodGuo/10(8) dGuo) and rat tissue (liver, 2.47 +/- 0.61 1,N(2)-epsilon dGuo/10(8) dGuo and 4.61 +/- 0.69 1,N(2)-propanodGuo/108 dGuo; brain, 2.96 +/- 1.43,N(2)-epsilon dGuo/10(8) dGuo and 5.66 +/- 3.70 1,N(2)-propanoclGuo/10(8) dGuo; and lung, 0,87 +/- 0.34 1,N(2)-edGuo/ 10(8) dGuo and 2.25 +/- 1.72 1,N(2)-propanodGuo/10(8) dGuo) were performed. The method described herein can be used to study the biological significance of exocyclic DNA adducts through the quantification of different adducts in humans and experimental an with pathological conditions and after air pollution exposure.

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An online, interactive tutorial, Smart Searcher, was introduced at Deakin University as part of the Iibrary's information skills program in late 2000. As liaison librarians responsible for library skills training we wanted to compare and evaluate this mode of instruction with our normal face-to-face delivery of library instruction. This study found that students with face-to-face instruction did, in fact, gain higher posttest mean scores than students completing the online tutorial. Also, students attending these library sessions felt more confident about their library skills than those in the online tutorial only session.

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Concerns over the overall cost of marketing research and the cost per usable response have in large measure caused marketing practitioners to turn to online marketing research techniques, either as a solus technique, or in a mixed mode application. However, the use of e-mail and mixed mode surveys such as postal invitations to complete online questionnaires present both familiar and new issues, as the extant literature illustrates. This paper examines an earlier study before reporting findings from the present study, which employs a method that ascertains the probability of commissioning and/or responding to four survey research methods, described in scenarios and delivered using e-mail and the World Wide Web (Web). It is evident that while perceptions of e-mail, the Internet, and privacy have changed since early use of the Internet and more particularly the World Wide Web, and there is acknowledgment in the literature concerning the lower costs and faster response speeds of online marketing research, small businesses do appear to discriminate in favour of targeted online survey methods over postal surveys, portrayed as scenarios in this study. They indicate a greater likelihood of responding to targeted, hybrid email/Web surveys than traditional postal surveys.

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Concerns over the overall cost of marketing research and the cost per usable response have in large measure caused marketing practitioners to turn to online marketing research techniques, either as a solus technique, or in a mixed mode application. However, the use of e-mail and mixed mode surveys such as postal invitations to complete online questionnaires present both familiar and new issues, as the extant literature illustrates. This paper examines an earlier study before reporting findings from the present study, which employs a method that ascertains the probability of commissioning four survey research methods, described in scenarios and delivered using e-mail and the World Wide Web (Web). It is evident that while perceptions of e-mail, the Internet, and privacy have changed since early use of the Internet and more particularly the World Wide Web, and there is acknowledgement in the literature concerning the lower costs and faster response speeds of online marketing research, small businesses do appear to discriminate in favour of targeted online survey methods over postal surveys, portrayed as scenarios in this study, but that this perception does not apply to all hybrid survey modes.

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Engineers Australia is the Australian professional body that accredits undergraduate engineering programs. It espouses an ‘outcomes-based’ program accreditation philosophy, but imposes mandatory ‘process’ requirements for off-campus programs that are in addition to the requirements for conventional on-campus programs. The focus on off-campus engineering study raises the question: how can learning outcomes, regardless of mode of study, be effectively measured? The current answer appears to be ‘graduate attributes’. The literature reveals a range of sophistication in approach to graduate attributes from identifying desirable graduate attributes, through to evidence-based certification of individual student attainment of graduate attributes. Many engineering accrediting bodies around the world identify student portfolios as a strategy for demonstrating student attainment of graduate attributes. The increasing use of online technology by students and educators alike, including as part of assessment, means that many of the reported applications of student portfolios are online portfolios. The effectiveness of online student portfolios will depend on them being embedded in day-to-day educational practice, rather than being an optional extra given a low priority by busy students. This paper presents a survey of the related literature and briefly outlines a project in progress at Deakin University to trial an online student portfolio.

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The increasing use of team assignments within higher education is well documented. The driving forces behind this include desires to facilitate reflective and collaborative learning, to develop generic teamwork skills for graduate employment and to reduce the grading workloads of faculty staff. Students however consistently report dissatisfaction when the assessment of team assignments produces a common grade for all team members. Self-andpeer-assessment (SAPA) is presented as a fair, valid and reliable method of producing information about ongoing team processes. This information can provide ongoing feedback to team members and rich formative data to instructors attempting to assess the team process and students’ teamwork skills. This data can also enable individualised summative assessment in dysfunctional teams or situations of uneven team member contributions. Whilst manual SAPA protocols can work effectively for smaller classes, computer-assisted SAPA offers a solution to the problems of large classes. This paper reports on the early stages of an online SAPA tool, originally developed for small classes of architecture students, adapted for use by very large business communication classes comprising up to 1000 students in a semester. This large unit is delivered on four Australian campuses as well as off-campus and in off-shore mode, by up to fourteen instructors at any one time. The paper documents how three researchers from very different backgrounds worked to create their own research team, implement a pilot study, and adapt the online tool, whilst adhering to comparability of assessment constraints and maintaining integrity of research design.