1,408 research outputs found
Psychometric assessment of ICILS test items on Hong Kong and Korean students: a Rasch analysis
Session 6C: ICILSThe IEA International Computer and Information Literacy Study (ICILS) 2013 is the first international comparative study aims to examine the outcome of Grade 8 students’ computer and information literacy (CIL) across 19 countries. The measurement of CIL focuses on students’ ability to use computer within and outside of school in the information age. Students are asked to complete two test modules, out of a total of four, which are conducted exclusively on computers. The present study reports psychometric properties of the test modules based on the results garnered from the Field Trial which was in preparation for the main study. A total sample of 804 students from Hong Kong and South Korea participated in the Field Trial. Rasch-anchored analysis was employed to analyze the data. The items for the four test modules demonstrated adequate psychometric properties – they target the students from Hong Kong and Korea well. However, significant Differential Item Functioning (DIF) was detected in some items from the 4 test modules. Future work on analysis on items reporting significant DIF will be carried out.postprin
Application of analytic tools for theory testing in organizational behaviour research
Best paper award in ManagementTrack: ManagementMany management journals insist on having a strong theoretical perspective for empirical studies. The purpose of this paper is to investigate the conditions under which one can claim that a study is theory-driven. The basic premise of our approach is to develop hypotheses that map directly onto the explanatory mechanisms that are employed to explain why a phenomenon would occur. We provide both conceptual and technical tools for ...published_or_final_versio
Roles of endothelin-1 in beta-amyloid-induced neurotoxicity in hippocampus: an implication for Alzheimer’s pathology
Poster F - Nervous System Disorders: abstract no. P3-F-012The British Neuroscience Association’s Festival of NeuroscienceAlzheimer’s disease (AD) is an incurable neurodegenerative disorder. Abnormal levels of endothelin-1 (ET-1) have been demonstrated in parietal white matter(1), cerebral cortex and vessels of the AD brain(2). Neuronal death and accumulation of beta-amyloid (Aβ) are prominent pathological features of AD. Significant neuronal death is found in Aβ-treated primary neurons and Aβ-overexpressing mouse models(3,4). ET-1 is a known vasoconstrictor and neuro-active peptide. ET-1 induces apoptosis in primary retinal neurons(5). In contrary, ET-receptor (ETR) type B agonist can rescue neurons from Aβ-induced apoptosis(6). These findings suggest ET-1 plays dual roles in neurodegeneration and neuroprotection, respectively. This study aims to investigate the effect of ET-1 on Aβ-induced cell death in hippocampal neurons. Primary hippocampal neurons were pretreated with or without ETR antagonists prior to the treatment of oligomeric form of Aβ1-42, ET-1 or both on 14 DIV. Cell viability was measured by MTT assay. Changes in protein expression in apoptotic and ET-1 signaling pathways were assessed by western-blot analysis. This study shed light on the roles of ET-1 in Aβ1-42-neurotoxicity, building upon which the ET-1 signaling pathway as a potential therapeutic target for AD can be further investigated.published_or_final_versio
Nasopharyngeal carcinoma: presenting symptoms and duration before diagnosis
This is a retrospective analysis of 4768 patients with undifferentiated or non-keratinising carcinoma of the nasopharynx who were treated during 1 January 1976 to 31 December 1985. The mean duration of symptoms before diagnosis was 8 months (range, 1-36 months for 95% of patients). A significant association between the duration of symptoms and the presenting stage was observed (P<0.001); 58% and 39% of stage I and stage V patients, respectively, reported as having had symptoms for less than 6 months. Of the later presenters (those having had symptoms for 6 months or longer), 89% were given a full course of radical megavoltage radiotherapy, but 6% were too advanced for any irradiation attempt. Consequently, the 10-year actuarial disease-specific survival was significantly higher among the early presenters: 48% versus 42% (P<0.001). The importance of early detection is emphasised.published_or_final_versio
Analyzing Recent Coronary Heart Disease Mortality Trends in Tunisia between 1997 and 2009.
BACKGROUND: In Tunisia, Cardiovascular Diseases are the leading causes of death (30%), 70% of those are coronary heart disease (CHD) deaths and population studies have demonstrated that major risk factor levels are increasing.
OBJECTIVE: To explain recent CHD trends in Tunisia between 1997 and 2009.
METHODS: DATA SOURCES: Published and unpublished data were identified by extensive searches, complemented with specifically designed surveys.
ANALYSIS: Data were integrated and analyzed using the previously validated IMPACT CHD policy model. Data items included: (i)number of CHD patients in specific groups (including acute coronary syndromes, congestive heart failure and chronic angina)(ii) uptake of specific medical and surgical treatments, and(iii) population trends in major cardiovascular risk factors (smoking, total cholesterol, systolic blood pressure (SBP), body mass index (BMI), diabetes and physical inactivity).
RESULTS: CHD mortality rates increased by 11.8% for men and 23.8% for women, resulting in 680 additional CHD deaths in 2009 compared with the 1997 baseline, after adjusting for population change. Almost all (98%) of this rise was explained by risk factor increases, though men and women differed. A large rise in total cholesterol level in men (0.73 mmol/L) generated 440 additional deaths. In women, a fall (-0.43 mmol/L), apparently avoided about 95 deaths. For SBP a rise in men (4 mmHg) generated 270 additional deaths. In women, a 2 mmHg fall avoided 65 deaths. BMI and diabetes increased substantially resulting respectively in 105 and 75 additional deaths. Increased treatment uptake prevented about 450 deaths in 2009. The most important contributions came from secondary prevention following Acute Myocardial Infarction (AMI) (95 fewer deaths), initial AMI treatments (90), antihypertensive medications (80) and unstable angina (75).
CONCLUSIONS: Recent trends in CHD mortality mainly reflected increases in major modifiable risk factors, notably SBP and cholesterol, BMI and diabetes. Current prevention strategies are mainly focused on treatments but should become more comprehensive
Cancer cell-secreted IGF2 instigates fibroblasts and bone marrow-derived vascular progenitor cells to promote cancer progression
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Nasopharyngeal carcinoma: time lapse before diagnosis and treatment
This is a descriptive study of 168 patients with nasopharyngeal carcinoma who were referred to public oncology departments for primary treatment between July and September 1996. The mean duration from the onset of the symptoms to histological diagnosis was 5.0 months; the duration ranged from 6.1 months (for patients presenting with nasal symptoms) to 1.8 months (for those with cranial nerve dysfunction). The mean period between the onset of symptoms and the seeking of medical advice was 2.9months. For 54% of the patients, there was a further delay of up to 2.4 months between the initial medical consultation and referral to the appropriate specialist. The majority (84%) of patients attended public institutions for histological confirmation. The mean total time taken from the onset of symptoms to the commencement of radiotherapy was 6.5 months (range, 1.3-74.0 months)---45% of the delay was attributed to the patient, 20% to initial consultations, 14% to diagnostic arrangement, and 21% to preparation for radiotherapy. Concerted efforts are needed to minimise further the time between the onset of symptoms and treatment. A substantial reduction in this delay can be achieved if both public and primary care doctors were made more aware of the significance of relevant symptoms.published_or_final_versio
Proactive and politically skilled professionals: What is the relationship with affective occupational commitment?
The aim of this study is to extend research on employee affective commitment in three ways: (1) instead of organizational commitment the focus is on occupational commitment; (2) the role of proactive personality on affective occupational commitment is examined; and (3) occupational satisfaction is examined as a mediator and political skills as moderator in the relationship between proactive personality and affective occupational commitment. Two connected studies, one in a hospital located in the private sector and one in a university located in the public sector, are carried out in Pakistan, drawing on a total sample of over 400 employees. The results show that proactive personality is positively related to affective occupational commitment, and that occupational satisfaction partly mediates the relationship between proactive personality and affective occupational commitment. No effect is found for a moderator effect of political skills in the relationship between proactive personality and affective occupational commitment. Political skills however moderate the relationship between proactive personality and affective organizational commitment
Habitat structure: a fundamental concept and framework for urban soil ecology
Habitat structure is defined as the composition and arrangement of physical matter at a location. Although habitat structure is the physical template underlying ecological patterns and processes, the concept is relatively unappreciated and underdeveloped in ecology. However, it provides a fundamental concept for urban ecology because human activities in urban ecosystems are often targeted toward management of habitat structure. In addition, the concept emphasizes the fine-scale, on-the-ground perspective needed in the study of urban soil ecology. To illustrate this, urban soil ecology research is summarized from the perspective of habitat structure effects. Among the key conclusions emerging from the literature review are: (1) habitat structure provides a unifying theme for multivariate research about urban soil ecology; (2) heterogeneous urban habitat structures influence soil ecological variables in different ways; (3) more research is needed to understand relationships among sociological variables, habitat structure patterns and urban soil ecology. To stimulate urban soil ecology research, a conceptual framework is presented to show the direct and indirect relationships among habitat structure and ecological variables. Because habitat structure serves as a physical link between sociocultural and ecological systems, it can be used as a focus for interdisciplinary and applied research (e.g., pest management) about the multiple, interactive effects of urbanization on the ecology of soils
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