8,271 research outputs found

    The Taxonomy of Goal-oriented Actions in Virtual Training Environments

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    With the shift of training scenarios to virtual worlds and assessment being an inevitable part of any teaching and learning process, we require sophisticated assessment methods to analyze action-sequences of learners according to reference solutions defined by experts and provide automated formative feedback. We propose the ‘Action-based Learning Assessment Method’ (ALAM) using an action taxonomy to classify recognized actions performed by the user in the virtual world. Most of these taxonomies were developed to model the behavior and performance of users. Yet, current taxonomies of human actions were developed based on need in specific research, still lacking a general taxonomy. The taxonomy of goal-oriented actions in virtual training environments was developed to overcome this problem and will be discussed in this paper

    Evolution of a stream ecosystem in recently deglaciated terrain

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    Climate change and associated glacial recession create new stream habitat that leads to the assembly of new riverine communities through primary succession. However, there are still very few studies of the patterns and processes of community assembly during primary succession for stream ecosystems. We illustrate the rapidity with which biotic communities can colonize and establish in recently formed streams by examining Stonefly Creek in Glacier Bay, Alaska (USA), which began to emerge from a remnant glacial ice mass between 1976 and 1979. By 2002, 57 macroinvertebrate and 27 microcrustacea species had become established. Within 10 years of the stream's formation, pink salmon and Dolly Varden charr colonized, followed by other fish species, including juvenile red and silver salmon, Coast Range sculpin, and sticklebacks. Stable-isotope analyses indicate that marine-derived nitrogen from the decay of salmon carcasses was substantially assimilated within the aquatic food web by 2004. The findings from Stonefly Creek are compared with those from a long-term study of a similarly formed but older stream (12 km to the northeast) to examine possible similarities in macroinvertebrate community and biological trait composition between streams at similar stages of development. Macroinvertebrate community assembly appears to have been initially strongly deterministic owing to low water temperature associated with remnant ice masses. In contrast, microcrustacean community assembly appears to have been more stochastic. However, as stream age and water temperature increased, macroinvertebrate colonization was also more stochastic, and taxonomic similarity between Stonefly Creek and a stream at the same stage of development was,<50%. However the most abundant taxa were similar, and functional diversity of the two communities was almost identical. Tolerance is suggested as the major mechanism of community assembly. The rapidity with which salmonids and invertebrate communities have become established across an entire watershed has implications for the conservation of biodiversity in freshwater habitats

    The fracture toughness of a range of cast steels

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    A range of plain carbon, carbon-manganese and low alloy cast steels were tested in order to determine their various fracture toughness values under elastic and elastic-plastic conditions. The main fracture toughness parameters which are considered are (1) Linear Elastic Fracture Mechanics (LEFM), (2) the J-Contour Integral, and (3) Crack Opening Displacement (COD). Results are obtained from fracture toughness specimens of various dimensions and the relevance of the validity criteria to cast steels is considered in some detail. In addition, the effect of casting position on specimen toughness values was noted. Valid KIC results according to LEFM, were obtained for three of the eight cast steels tested. Although KIC values from LEFM were not obtained from the remaining five steels, critical COD and J-integral values were determined. It is postulated that these values and particularly the critical J values can be used, with confidence for material selection or in defect tolerance calculations using these steels. Toughness values were found to vary with casting position in several of the steels tested and the possible reasons for such variations are discussed in the Thesis

    Climate change and floods in Yemen: Impacts on food security and options for adaptation

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    This paper uses both a global and local perspective to assess the impacts of climate change on the Yemeni economy, agriculture, and household income and food security. The major impact channels of climate change are through changing world food prices as a result of global food scarcities, long-term local yield changes as a result of temperature and rainfall variations, and damages and losses of cropland, fruit trees, livestock, and infrastructure as a result of natural disasters such as recurrent storms and floods. Moreover, spatial variation in climate change impacts within Yemen means that such effects can vary across subnational regions. We develop a recursive dynamic computable general equilibrium (DCGE) model with six agroecological zones to capture linkages between climate change, production, and household incomes. We also capture changes in per capita calorie consumption in response to changing household expenditure for assessing changes in people's hunger situation as a measure for food security. Given the high uncertainty surrounding future global food prices and local yields, all simulations are run under two global climate scenarios. The results of the CGE simulations suggest that climate-change-induced higher global prices for food will lower Yemen's overall GDP growth, raise agricultural GDP, decrease real household incomes, and increase the number of hungry people. Local impacts of climate change are different for the two climate scenarios. Overall, the long-term implications of climate change (local and global) lead to a total accumulated reduction of household welfare of between US5.7and5.7 and 9.2 billion by 2050 under MIR or CSI conditions, respectively. Moreover, between 80,000 and 270,000 people could go hungry due to climate change. Rural households are harder hit than urban households, and among the rural households the non-farm households suffer most. This household group is projected to lose an accumulated 3.5 to 5.7 billion US$ as a consequence of longer term climate change by 2050. In addition to the longer-term climate change effects, climate variability is shown to induce heavy economic losses and spikes in food insecurity. The impact assessment of the October 2008 tropical storm and floods in the Wadi Hadramout puts the total cumulated real income loss over the period 2008-12 at 180 percent of pre-flood agricultural value added. Due to the direct flood loss, farmers in the flooding areas suffer most in the year of the flood occurrence, where the percentage of hungry people living from farming spiked by about 15 percentage points as an immediate result of the flood. Action to mitigate the negative effects of climate change and variability should to be taken on the global and local level. A global action plan for improving food security combined with a better integration of climate change in national development strategies, agricultural and rural policies, and disaster risk management and social protection policies will be keys for improving the resilience of Yemen and Yemenis to climate change.Climate change, Development, flood, food security, Growth, Hunger,

    Cerebral venous thrombosis: clinical predictors and emerging treatments

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    Global and local economic impacts of climate change in Syria and options for adaptation:

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    There is broad consensus among scientists that climate change is altering weather patterns around the world. However, economists are only beginning to develop tools that allow for the quantification of such weather changes on countries' economies and people. This paper presents a modeling suite that links the downscaling of global climate models, crop modeling, global economic modeling, and subnational-level computable equilibrium modeling. Important to note is that this approach allows for decomposing the potential global and local economic effects on countries, including various economic sectors and different household groups. We apply this modeling suite to Syria, a relevant case study given the country's location in a region that is consistently projected to be among those hit hardest by climate change. Despite a certain degree of endogenous adaptation, local impacts of climate change (through declining yields) are likely to affect Syria beyond the agricultural sector and farmers and also reduce economy-wide growth and incomes of urban households in the long term. The overall effects of global climate change (through higher food prices) are also negative, but some farmers can reap the benefit of higher prices. Combining local and global climate change scenarios shows welfare losses across all rural and urban household groups of between 1.6 – 2.8 percent annually, whereas the poorest household groups are the hardest hit. Finally, while there is some evidence that droughts may become more frequent in the future, it is clear that even without an increase in frequency, drought impacts will continue to put a significant burden on Syria's economy and people. Action to mitigate the negative effects of climate change and variability should to be taken on the global and local level. A global action plan for improving food security and better integration of climate change in national development strategies, agricultural and rural policies, and disaster risk management and social protection policies will be keys for improving the resilience of countries and people to climate change.Climate change, Development, drought, Growth, Poverty,

    Baseline features and reasons for nonparticipation in the Colonoscopy Versus Fecal Immunochemical Test in Reducing Mortality From Colorectal Cancer (CONFIRM) study, a colorectal cancer screening trial

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    IMPORTANCE: The Colonoscopy Versus Fecal Immunochemical Test in Reducing Mortality From Colorectal Cancer (CONFIRM) randomized clinical trial sought to recruit 50 000 adults into a study comparing colorectal cancer (CRC) mortality outcomes after randomization to either an annual fecal immunochemical test (FIT) or colonoscopy. OBJECTIVE: To (1) describe study participant characteristics and (2) examine who declined participation because of a preference for colonoscopy or stool testing (ie, fecal occult blood test [FOBT]/FIT) and assess that preference\u27s association with geographic and temporal factors. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study within CONFIRM, which completed enrollment through 46 Department of Veterans Affairs medical centers between May 22, 2012, and December 1, 2017, with follow-up planned through 2028, comprised veterans aged 50 to 75 years with an average CRC risk and due for screening. Data were analyzed between March 7 and December 5, 2022. EXPOSURE: Case report forms were used to capture enrolled participant data and reasons for declining participation among otherwise eligible individuals. MAIN OUTCOMES AND MEASURES: Descriptive statistics were used to characterize the cohort overall and by intervention. Among individuals declining participation, logistic regression was used to compare preference for FOBT/FIT or colonoscopy by recruitment region and year. RESULTS: A total of 50 126 participants were recruited (mean [SD] age, 59.1 [6.9] years; 46 618 [93.0%] male and 3508 [7.0%] female). The cohort was racially and ethnically diverse, with 748 (1.5%) identifying as Asian, 12 021 (24.0%) as Black, 415 (0.8%) as Native American or Alaska Native, 34 629 (69.1%) as White, and 1877 (3.7%) as other race, including multiracial; and 5734 (11.4%) as having Hispanic ethnicity. Of the 11 109 eligible individuals who declined participation (18.0%), 4824 (43.4%) declined due to a stated preference for a specific screening test, with FOBT/FIT being the most preferred method (2820 [58.5%]) vs colonoscopy (1958 [40.6%]; P \u3c .001) or other screening tests (46 [1.0%] P \u3c .001). Preference for FOBT/FIT was strongest in the West (963 of 1472 [65.4%]) and modest elsewhere, ranging from 199 of 371 (53.6%) in the Northeast to 884 of 1543 (57.3%) in the Midwest (P = .001). Adjusting for region, the preference for FOBT/FIT increased by 19% per recruitment year (odds ratio, 1.19; 95% CI, 1.14-1.25). CONCLUSIONS AND RELEVANCE: In this cross-sectional analysis of veterans choosing nonenrollment in the CONFIRM study, those who declined participation more often preferred FOBT or FIT over colonoscopy. This preference increased over time and was strongest in the western US and may provide insight into trends in CRC screening preferences

    Glocalization and everyday life

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    This Special Issue of Glocalism bring together scholars from different countries and with different approaches to reflect on the relation between the idea of "glocalization" and that of "everyday life". The Index can be found here: https://glocalismjournal.org/issue-2020-3-glocalization-and-everyday-life

    Knowledge, attitudes, and practices of 50 patients with surgically treated cystic echinococcosis from Basrah Province, Iraq

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    Cystic echinococcosis (CE) is recognised worldwide as a neglected disease of public health concern, particularly in low- and middle-income countries. The objectives of this study were to describe, using a questionnaire survey, the characteristics, attitudes, knowledge, and practices of patients with CE from Basrah Province, Iraq. We interviewed 50 patients, 31 female and 19 male, of whom, 74% originated from rural areas. Approximately half (48%) of the participants reported slaughtering livestock at home for their families’ consumption; 78% indicated the presence of a large number of stray dogs roaming freely about their village; 86% reported that they never boiled water prior to drinking it; and 26% reported not washing vegetables prior to eating them. Although a large proportion of the participants (72%) had heard of hydatid disease prior to becoming ill, over half (57%) were not aware how the disease was transmitted from animals to humans. This study highlighted a gap in health education efforts regarding CE in Southern Iraq, with a lack of counselling of patients on how to prevent reinfection. An intensive control programme should be implemented and founded on health education to reduce CE disease in Basrah
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