258 research outputs found

    Formative peer assessment in a CSCL environment

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    In this case study our aim was to gain more insight in the possibilities of qualitative formative peer assessment in a computer supported collaborative learning (CSCL) environment. An approach was chosen in which peer assessment was operationalised in assessment assignments and assessment tools that were embedded in the course material. The course concerned a higher education case-based virtual seminar, in which students were asked to conduct research and write a report in small multidisciplinary teams. The assessment assignments contained the discussion of assessment criteria, the assessment of a group report of a fellow group, and writing an assessment report. A list of feedback rules was one of the assessment tools. A qualitative oriented study was conducted, focussing on the attitude of students towards peer assessment and practical use of peer assessment assignments and tools. Results showed that students’ attitude towards peer assessment was positive and that assessment assignments had added value. However, not all students fulfilled all assessment assignments. Recommendations for implementation of peer assessment in CSCL environments as well as suggestions for future research are discussed

    Designing electronic collaborative learning environments

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    Electronic collaborative learning environments for learning and working are in vogue. Designers design them according to their own constructivist interpretations of what collaborative learning is and what it should achieve. Educators employ them with different educational approaches and in diverse situations to achieve different ends. Students use them, sometimes very enthusiastically, but often in a perfunctory way. Finally, researchers study them and—as is usually the case when apples and oranges are compared—find no conclusive evidence as to whether or not they work, where they do or do not work, when they do or do not work and, most importantly, why, they do or do not work. This contribution presents an affordance framework for such collaborative learning environments; an interaction design procedure for designing, developing, and implementing them; and an educational affordance approach to the use of tasks in those environments. It also presents the results of three projects dealing with these three issues

    Pulse separation control for mode-locked far-infrared p-Ge lasers

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    Active mode locking of the far-infrared p-Ge laser giving a train of 200 ps pulses is achieved via gain modulation by applying an rf electric field together with an additional bias at one end of the crystal parallel to the Voigt-configured magnetic field. Harmonic mode locking yields a train of pulse pairs with variable time separation from zero to half the roundtrip period, where pulse separation is electrically controlled by the external bias to the rf field

    Polarization stabilization in vertical-cavity surface-emitting lasers through asymmetric current injection

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    We present experimental evidence that asymmetric current injection in intracavity contacted vertical-cavity surface-emitting lasers (VCSELs) stabilizes the polarization of the emitted light. Anisotropies in the gain and loss mechanisms introduced by asymmetric current injection are considered to explain this effect. The design scheme opens perspectives to obtain actual polarization control in VCSEL

    First-line gemcitabine with cisplatin or epirubicin in advanced non-small-cell lung cancer: a phase III trial

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    The purpose of our study was to compare progression-free survival and quality of life (QOL) after cisplatin-gemcitabine (CG) or epirubicin-gemcitabine (EG) in chemotherapy-naive patients with unresectable non-small-cell lung cancer. Patients (n = 240) were randomised to receive gemcitabine 1125 mg m(-2) (days 1 and 8) plus either cisplatin 80 mg m(-2) (day 2) or epirubicin 100 mg m(-2) (day 1) every 3 weeks for a maximum of five cycles. Eligible patients had normal organ functions and Eastern Cooperative Oncology Group performance status less than or equal to2. QOL was measured with European Organisation for Research and Treatment of Cancer QLQ-C30 and LC13 questionnaires. There were no significant differences in median progression-free survival (CG 26 weeks, EG 23 weeks), median overall survival (CG 43 weeks, EG 36 weeks), or tumour response rates (CG 46%, EG 36%). Toxicity was mainly haematologic. In the EG arm granulocytopenia occurred more frequently, leading to more febrile neutropenia. Also, elevation of serum transaminases, mucositis, fever, and decline in LVEF were more common in the EG arm. In the CG arm, more patients experienced elevated serum creatinine levels, sensory neuropathy, nausea, and vomiting. Global QOL was not different in both arms. Progression-free survival, overall survival, response rate, and QOL were not different between both arms; however, overall toxicity was more severe in the EG arm

    Accuracy of patient-reported data for an online patient registry of autoimmune myasthenia gravis and Lambert-Eaton myasthenic syndrome

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    Disorders of the neuromuscular junction (NMJ) comprise a spectrum of rare diseases causing muscle fatigability and weakness, leading to life-long effects on quality of life. We established the Dutch-Belgian registry for NMJ disorders, based on a unique combination of patient -and physician-reported information. Information on natural course, disease burden, prevalence of complications and comorbidity is collected through patient-reported standardized questionnaires and verified using medical documentation. Currently, the registry contains information of 565 Myasthenia Gravis (MG) patients and 38 Lambert-Eaton myasthenic syndrome (LEMS) patients, constituting approximately 25% (MG) and 80% (LEMS) of patients in the Netherlands. This is a very large registry, with the highest participation rate per capita. In addition to confirming many disease characteristics previously described in the literature, this registry provides several novel insights. The reported rate of potentially corticosteroid-related comorbidity, including hypertension, heart disease, osteoporosis and type 2 diabetes was high, emphasizing the need to commence corticosteroid-sparing immune suppressive treatment as soon as possible. The reported rate of other auto-immune diseases is far higher than previously expected: 27% of MG and 38% of LEMS patients, and a surprisingly high number of MG patients (47%) is unaware of their antibody status. In conclusion, this registry provides a valuable collection of information regarding MG and LEMS disease course. Continuous collection of annual follow-up data will provide further longitudinal insights in disease burden, course and treatment effect. (c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )Neurological Motor Disorder

    Actively mode-locked p-Ge laser in Faraday configuration

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    Active mode locking of the far-infrared p-Ge laser has been achieved in the Faraday configuration of electric and magnetic fields applied to the laser crystal. The laser generates 200 ps pulses of 80-110 cm(-1) radiation with a laser-cavity roundtrip frequency of 454 MHz. The mechanism of gain modulation by the external rf electric field is based on induced electric-field gradients inside the active crystal and requires less rf power than was found previously for Voigt geometry

    EXPERIENCES OF DRUG USERS IN IIA CLASS JAIL YOGYAKARTA

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    United Nations Office on Drugs and Crime (UNODC) estimated that about 149-272 million people or 3.3 % - 6.1 % of world population aged 15-64 years used drugs (even once) during their life time. This estimation will increase with time (BNN, 2011). The number of prisoners suffering HIV/AIDS in recent years were increasing as well if compared to its numbers in the year 2011 from 787 people to 1042 people. It was estimated that in the year 2015, the number of drug users in Indonesia would increase to 5.8 million people, since the number of drug users at the present time were reached 4 million people. For the time being, in Yogyakarta second A class drug jail , the number of drug users were 256 people; this number were constant; its mean that if there was prisoner got his / her freedom, another prisoner was incoming. Data from BNN in August 2013 years, 70% of 4 million drug users in Indonesia were workers (productive aged). Aim; To discovered population research experiences that cause them used drugs and depend on its. Research method: This was qualitative research with phenomenological approach. Data gathering technique were deep interview and FGD toward 30 respondents. Data were analyzed using reduction, data display, and conclusion drawing/verification. The majority of respondents mentioned that they used drugs because of they wanted to know and the influence of friends. Drugs, kinds of sabu, used to increase energy and ganja were used to obtain peacefulness. Drugs users wanted to use its forever; therefore, they wanted to stop because of punishment to be in jail not because of the drugs had negative effects to the body. The majority of respondents mentioned that to stop using drugs must be self motivated; on the contrary, the obstacle to stop using drugs because of missing sensation to use it. They named it suggest. Using drugs were conducted by research population because of environmental influence, to increase energy and to obtain peacefulness. Keywords : The experiences of drug use
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