16 research outputs found

    Predictors of Examination Integrity among Secondary School Students: Framework for Proactive Actions Against Examination Malpractices

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    This study focused on determination of predictors of academic integrity during examinations among secondary school students. The population consisted of 300,000 final year secondary school students in South-South geopolitical zone of Nigeria out of which a sample of 3000 students (1720 females and 1280 males) were selected through multistage proportionate stratified random sampling technique. Analysis of data collected with the aid of Examination Integrity Questionnaire (EIQ) that was adopted and validated by the researchers showed significant influence of students’ gender on academic integrity during examinations with female students having higher mean score on examination integrity. Moreover, Study Habits, Examination Ethics, Examination Anxiety, Moral Background, Examination Attitude and Past Experience were significant predictors of examination integrity of students. Past experience was the strongest predictor of students’ examination integrity. However, there was no significant impact of Age on students’ examination integrity. These findings have implications for preventive actions against examination malpractices. For instance, proactive actions should be targeted at improving students’ study habits, examination anxiety, moral reasoning, attitude towards cheating or examination ethics and subjective norms before they sit for school examinations. This proactive action framework based on the Modified Theory of Planned Behaviour may be more effective in curbing examination malpractices than the extant practice of administering punitive measures after examination ethics violations

    Oxford Nanopore sequencing, hybrid error correction, and de novo assembly of a eukaryotic genome

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    Monitoring the progress of DNA molecules through a membrane pore has been postulated as a method for sequencing DNA for several decades. Recently, a nanopore-based sequencing instrument, the Oxford Nanopore MinION, has become available, and we used this for sequencing the Saccharomyces cerevisiae genome. To make use of these data, we developed a novel open-source hybrid error correction algorithm Nanocorr specifically for Oxford Nanopore reads, because existing packages were incapable of assembling the long read lengths (5-50 kbp) at such high error rates (between approximately 5% and 40% error). With this new method, we were able to perform a hybrid error correction of the nanopore reads using complementary MiSeq data and produce a de novo assembly that is highly contiguous and accurate: The contig N50 length is more than ten times greater than an Illumina-only assembly (678 kb versus 59.9 kbp) and has >99.88% consensus identity when compared to the reference. Furthermore, the assembly with the long nanopore reads presents a much more complete representation of the features of the genome and correctly assembles gene cassettes, rRNAs, transposable elements, and other genomic features that were almost entirely absent in the Illumina-only assembly

    Climate change projections using the IPSL-CM5 Earth System Model: from CMIP3 to CMIP5

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    We present the global general circulation model IPSL-CM5 developed to study the long-term response of the climate system to natural and anthropogenic forcings as part of the 5th Phase of the Coupled Model Intercomparison Project (CMIP5). This model includes an interactive carbon cycle, a representation of tropospheric and stratospheric chemistry, and a comprehensive representation of aerosols. As it represents the principal dynamical, physical, and bio-geochemical processes relevant to the climate system, it may be referred to as an Earth System Model. However, the IPSL-CM5 model may be used in a multitude of configurations associated with different boundary conditions and with a range of complexities in terms of processes and interactions. This paper presents an overview of the different model components and explains how they were coupled and used to simulate historical climate changes over the past 150 years and different scenarios of future climate change. A single version of the IPSL-CM5 model (IPSL-CM5A-LR) was used to provide climate projections associated with different socio-economic scenarios, including the different Representative Concentration Pathways considered by CMIP5 and several scenarios from the Special Report on Emission Scenarios considered by CMIP3. Results suggest that the magnitude of global warming projections primarily depends on the socio-economic scenario considered, that there is potential for an aggressive mitigation policy to limit global warming to about two degrees, and that the behavior of some components of the climate system such as the Arctic sea ice and the Atlantic Meridional Overturning Circulation may change drastically by the end of the twenty-first century in the case of a no climate policy scenario. Although the magnitude of regional temperature and precipitation changes depends fairly linearly on the magnitude of the projected global warming (and thus on the scenario considered), the geographical pattern of these changes is strikingly similar for the different scenarios. The representation of atmospheric physical processes in the model is shown to strongly influence the simulated climate variability and both the magnitude and pattern of the projected climate changes

    Predictors of Examination Integrity among Secondary School Students: Framework for Proactive Actions Against Examination Malpractices

    No full text
    This study focused on determination of predictors of academic integrity during examinations among secondary school students. The population consisted of 300,000 final year secondary school students in South-South geopolitical zone of Nigeria out of which a sample of 3000 students (1720 females and 1280 males) were selected through multistage proportionate stratified random sampling technique. Analysis of data collected with the aid of Examination Integrity Questionnaire (EIQ) that was adopted and validated by the researchers showed significant influence of students’ gender on academic integrity during examinations with female students having higher mean score on examination integrity. Moreover, Study Habits, Examination Ethics, Examination Anxiety, Moral Background, Examination Attitude and Past Experience were significant predictors of examination integrity of students. Past experience was the strongest predictor of students’ examination integrity. However, there was no significant impact of Age on students’ examination integrity. These findings have implications for preventive actions against examination malpractices. For instance, proactive actions should be targeted at improving students’ study habits, examination anxiety, moral reasoning, attitude towards cheating or examination ethics and subjective norms before they sit for school examinations. This proactive action framework based on the Modified Theory of Planned Behaviour may be more effective in curbing examination malpractices than the extant practice of administering punitive measures after examination ethics violations

    Multi-grid algorithm for passive tracer transport in the NEMO ocean circulation model : a case study with the NEMO OGCM (version 3.6)

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    Ocean biogeochemical models are key tools for both scientific and operational applications. Nevertheless the cost of these models is often expensive because of the large number of biogeochemical tracers. This has motivated the development of multi-grid approaches where ocean dynamics and tracer transport are computed on grids of different spatial resolution. However, existing multi-grid approaches to tracer transport in ocean modelling do not allow the computation of ocean dynamics and tracer transport simultaneously. This paper describes a new multi-grid approach developed for accelerating the computation of passive tracer transport in the Nucleus for European Modelling of the Ocean (NEMO) ocean circulation model. In practice, passive tracer transport is computed at runtime on a grid with coarser spatial resolution than the hydrodynamics, which reduces the CPU cost of computing the evolution of tracers. We describe the multi-grid algorithm, its practical implementation in the NEMO ocean model, and discuss its performance on the basis of a series of sensitivity experiments with global ocean model configurations. Our experiments confirm that the spatial resolution of hydrodynamical fields can be coarsened by a factor of 3 in both horizontal directions without significantly affecting the resolved passive tracer fields. Overall, the proposed algorithm yields a reduction by a factor of 7 of the overhead associated with running a full biogeochemical model like PISCES (with 24 passive tracers). Propositions for further reducing this cost without affecting the resolved solution are discussed

    Coastal-ocean uptake of anthropogenic carbon

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    Anthropogenic changes in atmosphere-ocean and atmosphere-land CO2 fluxes have been quantified extensively, but few studies have addressed the connection between land and ocean. In this transition zone, the coastal ocean, spatial and temporal data coverage is inadequate to assess its global budget. Thus we use a global ocean biogeochemical model to assess the coastal ocean's global inventory of anthropogenic CO2 and its spatial variability. We used an intermediate resolution, eddying version of the NEMO-PISCES model (ORCA05), varying from 20 to 50 km horizontally, i.e. coarse enough to allow multiple century-scale simulations but finer than coarse-resolution models (similar to 200 km) to better resolve coastal bathymetry and complex coastal currents. Here we define the coastal zone as the continental shelf area, excluding the proximal zone. Evaluation of the simulated air-sea fluxes of total CO2 for 45 coastal regions gave a correlation coefficient R of 0.8 when compared to observation-based estimates. Simulated global uptake of anthropogenic carbon results averaged 2.3 Pg C yr(-1) during the years 1993-2012, consistent with previous estimates. Yet only 0.1 Pg C yr(-1) of that is absorbed by the global coastal ocean. That represents 4.5% of the anthropogenic carbon uptake of the global ocean, less than the 7.5% proportion of coastal-to-global-ocean surface areas. Coastal uptake is weakened due to a bottleneck in offshore transport, which is inadequate to reduce the mean anthropogenic carbon concentration of coastal waters to the mean level found in the open-ocean mixed layer

    Presentation and analysis of the IPSL and CNRM climate models used in CMIP5

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    We have assessed the ability of a common ocean biogeochemical model, PISCES, to match relevant modern data fields across a range of ocean circulation fields from three distinct Earth system models: IPSL-CM4-LOOP, IPSL-CM5A-LR and CNRM-CM5.1. The first of these Earth system models has contributed to the IPCC 4th assessment report, while the latter two are contributing to the ongoing IPCC 5th assessment report. These models differ with respect to their atmospheric component, ocean subgrid-scale physics and resolution. The simulated vertical distribution of biogeochemical tracers suffer from biases in ocean circulation and a poor representation of the sinking fluxes of matter. Nevertheless, differences between upper and deep ocean model skills significantly point to changes in the underlying model representations of ocean circulation. IPSL-CM5A-LR and CNRM-CM5.1 poorly represent deep-ocean circulation compared to IPSL-CM4-LOOP degrading the vertical distribution of biogeochemical tracers. However, their representations of surface wind, wind stress, mixed-layer depth and geostrophic circulations (e.g., Antarctic Circumpolar Current) have been improved compared to IPSL-CM4-LOOP. These improvements result in a better representation of large-scale structure of biogeochemical fields in the upper ocean. In particular, a deepening of 20-40 m of the summer mixed-layer depth allows to capture the 0-0.5 mu gChl L-1 concentrations class of surface chlorophyll in the Southern Ocean. Further improvements in the representation of the ocean mixed-layer and deep-ocean ventilation are needed for the next generations of models development to better simulate marine biogeochemistry. In order to better constrain ocean dynamics, we suggest that biogeochemical or passive tracer modules should be used routinely for both model development and model intercomparisons
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