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The Impact of Formative Assessment on Cognitive Engagement Among Undergrad Engineering Students With Different Levels of Need for Cognitive Closure
No full textIn education, assessments are used to evaluate student learning (e.g., tests and assignments) or in the form of formative assessment, to both assess and support learning through feedback and reflection. One of the most important aspects of formative assessment is feedback, which encourages self-reflection during the learning process to develop student confidence, engagement, and academic performance. Also, formative assessment helps students to take ownership of their learning by assessing their problem-solving strategies and then working towards a greater learning outcome. Prior research has shown that the Need for Cognitive Closure (NFCC) level, gender, and prior academic achievement level can influence students\u27 responses to feedback in ways that ultimately change the cognitive engagement. This research explored the influence of formative assessment on cognitive engagement of undergraduate engineering students during problem-solving activities, considering differences in their gender, Need for Cognitive Closure (NFCC), and prior academic achievement levels. However, all students respond to formative assessments differently during the problem-solving task depending on several traits (i.e., gender, NFCC, and prior academic achievement levels). Need for Cognitive Closure (NFCC) is a psychological construct that refers to an individual\u27s desire for a firm answer to a question and an aversion toward ambiguity or uncertainty. Individuals with high NFCC are motivated to make quick decisions and prefer structured, predictable environments, while those with low NFCC are more comfortable with ambiguity, open-endedness, and prolonged information processing. Low NFCC students are more open to alternative ideas, comfortable with uncertainty, and tolerate ambiguity during the problem-solving task. The study took place at a public land-grant university in the western United States. America. Participants were undergraduate engineering students and enrolled in an engineering mechanics statics course. All undergraduate students were surveyed for demographic data as well as the measurement of NFCC. Based on this survey data, eight student participants were chosen based on gender (females and males), NFCC level (high and low), and academic performance (high and low), and they took part in deeper qualitative analyses. The eight participants completed two problem-solving tasks individually. The first problem-solving task was without formative assessment, while the second problem-solving task incorporated formative assessment. During both problem-solving task sessions, students verbalized their thoughts. These sessions were recorded, transcribed, and analyzed using the ICAP framework to identify the modes of engagement, such as Passive (listening or reading), Active (writing, following problem-solving steps without giving reasons), or Constructive (providing reasons and making connections with prior knowledge). The analysis examined the shift in students’ cognitive engagement during the first and second problem-solving tasks. The research findings suggest that formative assessment fostered cognitive engagement for all participants; however, students with low NFCC and low prior academic achievement demonstrated higher, deeper-level cognitive engagement. These students showed surface-level cognitive engagement during the first problem-solving activity but exhibited a significant shift to deeper-level cognitive engagement after receiving formative assessment, which is a more analytical and reflective form of engagement. Although high NFCC students who prefer structure demonstrated significant change in cognitive engagement after they received feedback, the shift was mainly the reduction in passive cognitive engagement and a slight increase in constructive engagement. Furthermore, female participants experienced greater changes in cognitive engagement after receiving formative assessment, thinking more about what they learned, and demonstrating more constructive engagement with less passive engagement. Male participants continued to display improvements as well, but it was less than female participants. This could be because female students were using formative assessment to reaffirm or modify their prior understanding, while male students may have had to reorganize their structure around the new learning techniques. Also, constructive engagement of high and low prior academic achievers was almost equally improved after receiving formative assessment during the second problem-solving task. However, lower prior academic achievers demonstrated slightly higher constructive engagement as compared to higher prior academic achievers, which indicates that the usage of timely and clear formative assessment can help students think more deeply about the content to assist with their learning. The research findings suggest that although formative assessment supports cognitive engagement and deeper learning, cognitive engagement is dependent on students\u27 traits, and an effective formative assessment should be structured and customized according to students’ diverse learning needs. Also, teachers should use formative assessments in daily instruction to provoke deeper, more reflective engagement. It further confirms that the use of assessment practices inclusiveness and equity, should be utilized appropriately to address diverse learners\u27 outcomes
A Fire Deficit Persists Across Diverse North American Forests Despite Recent Increases in Area Burned
No full textRapid increases in wildfire area burned across North American forests pose novel challenges for managers and society. Increasing area burned raises questions about whether, and to what degree, contemporary fire regimes (1984–2022) are still departed from historical fire regimes (pre-1880). We use the North American tree-ring fire-scar network (NAFSN), a multi-century record comprising \u3e 1800 fire-scar sites spanning diverse forest types, and contemporary fire perimeters to ask whether there is a contemporary fire surplus or fire deficit, and whether recent fire years are unprecedented relative to historical fire regimes. Our results indicate, despite increasing area burned in recent decades, that a widespread fire deficit persists across a range of forest types and recent years with exceptionally high area burned are not unprecedented when considering the multi-century perspective offered by fire-scarred trees. For example, ‘record’ contemporary fire years such as 2020 burned 6% of NAFSN sites—the historical average—well below the historical maximum of 29% sites that burned in 1748. Although contemporary fire extent is not unprecedented across many North American forests, there is abundant evidence that unprecedented contemporary fire severity is driving forest loss in many ecosystems and adversely impacting human lives, infrastructure, and water supplies
Plant Diversity Dynamics Over Space and Time in a Warming Arctic
No full textThe Arctic is warming four times faster than the global average1 and plant communities are responding through shifts in species abundance, composition and distribution2,3,4. However, the direction and magnitude of local changes in plant diversity in the Arctic have not been quantified. Using a compilation of 42,234 records of 490 vascular plant species from 2,174 plots across the Arctic, here we quantified temporal changes in species richness and composition through repeat surveys between 1981 and 2022. We also identified the geographical, climatic and biotic drivers behind these changes. We found greater species richness at lower latitudes and warmer sites, but no indication that, on average, species richness had changed directionally over time. However, species turnover was widespread, with 59% of plots gaining and/or losing species. Proportions of species gains and losses were greater where temperatures had increased the most. Shrub expansion, particularly of erect shrubs, was associated with greater species losses and decreasing species richness. Despite changes in plant composition, Arctic plant communities did not become more similar to each other, suggesting no biotic homogenization so far. Overall, Arctic plant communities changed in richness and composition in different directions, with temperature and plant–plant interactions emerging as the main drivers of change. Our findings demonstrate how climate and biotic drivers can act in concert to alter plant composition, which could precede future biodiversity changes that are likely to affect ecosystem function, wildlife habitats and the livelihoods of Arctic peoples5,6
An End-To-End Concatenated CNN Attention Model for the Classification of Lung Cancer With XAI Techniques
No full textIn the field of medical imaging, deep learning (DL) techniques have made significant contributions to the detection and classification of various cancers. Identifying the precise regions in medical images containing cancerous cells plays a crucial role in the diagnostic process. Early and accurate cancer detection is essential for effective treatment and improved patient outcomes. However, manual diagnosis is labor-intensive, requiring the specialized expertise of radiologists, and the increasing number of cancer cases presents challenges in processing large volumes of image data efficiently. To address these challenges, an end-to-end concatenated Convolutional Neural Network (CNN) attention model has been proposed for automatic lung cancer classification. This approach integrates two distinct CNNs, followed by a multi-layer perceptron (MLP) and a multi-head attention (MHA) mechanism, to enhance performance. The model leverages explainable AI techniques, such as gradient-weighted class activation mapping (grad-CAM) and Shapley additive explanations (SHAP), to highlight critical regions within the images that influence the decision-making process. This model achieves impressive performance, with an accuracy of 99.54%, precision of 99.31%, recall of 99.95%, F1-score of 99.66%, and an AUC of 99.97%. These results demonstrate that this approach not only surpasses existing methods but also provides a highly accurate and interpretable solution. By reducing the need for extensive manual intervention, this model enables faster and more reliable lung cancer diagnosis, paving the way for timely and effective treatments
Elevated Extinction Risk in Over One-Fifth of Native North American Pollinators
No full textPollinators are critical for food production and ecosystem function. Although native pollinators are thought to be declining, the evidence is limited. This first, taxonomically diverse assessment for mainland North America north of Mexico reveals that 22.6% (20.6 to 29.6%) of the 1,579 species in the best-studied vertebrate and insect pollinator groups have elevated risk of extinction. All three pollinating bat species are at risk and bees are the insect group most at risk (best estimate, 34.7% of 472 species assessed, range 30.3 to 43.0%). Substantial numbers of butterflies (19.5% of 632 species, range 19.1 to 21.0%) and moths (16.1% of 142 species, range 15.5 to 19.0%) are also at risk, with flower flies (14.7% of 295 species, range 11.5 to 32.9%), beetles (12.5% of 18 species, range 11.1 to 22.2%), and hummingbirds (0% of 17 species) more secure. At-risk pollinators are concentrated where diversity is highest, in the southwestern United States. Threats to pollinators vary geographically: climate change in the West and North, agriculture in the Great Plains, and pollution, agriculture, and urban development in the East. Woodland, shrubland/chaparral, and grassland habitats support the greatest numbers of at-risk pollinators. Strategies for improving pollinator habitat are increasingly available, and this study identifies species, habitats, and threats most in need of conservation actions at state, provincial, territorial, national, and continental levels
Effects of Fire Recurrence and Severity on Mediterranean Vegetation Dynamics: Implications for Structure and Composition in Southern Spain
No full textMost Mediterranean ecosystems have been profoundly shaped by wildfires, driving the evolution of plant species. Through photo interpretation and field inventories, this research assessed vegetation dynamics from 1984 to 2021, examining how fire severity and recurrence, key fire regime variables, influenced changes in structure and woody species diversity. Using two burn scars (1988 and 2006), we identified four scenarios dominated by Pinus pinea tree species: control (unburned), areas burned once (either in 1988 or 2006), and twice (in both 1988 and 2006).
Areas affected by two high-severity fires experienced the most pronounced expansion of dense shrubland. However, when fire severity was moderate, wildfires led to a significant decline in understory cover in dense and open forests. Pinus pinea regeneration was influenced by fire severity and recurrence. It was absent in areas burned twice with at least one high-severity fire but showed an increased compared to control areas in areas burned with moderate fire severity without recurrence. Wildfires increased biodiversity, particularly in areas burned with high severity. The Sørensen and Jaccard indices showed the highest species diversity recovery in dense forest understory after a single moderate-severity fire in 1988. This study offers a novel approach by considering both fire recurrence and severity, along with a medium-term timeframe, in contrast to most studies focusing on short-term vegetation dynamics after single fires. Monitoring spatio-temporal dynamics is crucial for guiding ecological restoration and wildfire prevention strategies
Evaluation of SARS-CoV-2 Antibody Detection Methods for Wild Cervidae
No full textWildlife surveillance programs often use serological data to monitor exposure to pathogens. Diagnostic sensitivity and specificity of a serological assay quantify the true positive and negative rates of the diagnostic assay, respectively. However, an assay’s accuracy can be affected by wild animals’ pathogen exposure history and quality of the sample collected, requiring separate estimates of an assay’s detection ability for wild-sampled animals where an animal’s true disease status is unknown (referred to hereafter as sampling sensitivity and specificity). We assessed the sampling sensitivity and specificity of a Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) surrogate virus neutralization test (sVNT) and conventional virus neutralization tests (cVNT) to detect antibodies for ancestral and Omicron B.1.1.529 variants of SARS-CoV-2 in wild white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus). We studied the influence of sample collection method using paired blood samples collected in serum separator tubes and on Nobuto strips from the same animal. Mean estimates of sampling sensitivity and specificity ranged from 0.21–0.95 and 0.94–1.00, respectively, varying by sample collection method, host species, and SARS-CoV-2 variant targeted by the assay. Broadly, sampling sensitivity was estimated to be higher for 1) sera collected in tubes, 2) detecting pre-Omicron SARS-CoV-2 variants, and 3) sVNT relative to cVNT assays. Sampling specificity tended to be high for all tests. We augmented our study with SARS-CoV-2 spike protein sequences derived from sampling locations and times coincident with white-tailed deer captures, finding common amino acid mutations relative to the sVNT Omicron antigen variant. The mutations may indicate that the SARS-CoV-2 variants circulating in cervids from 2021 through 2024 may be better adapted to cervid hosts and more closely related to variants that circulated in humans prior to Omicron variants. We conclude our study with an inter-test comparison of sVNT results, revealing that 40 % inhibition is an optimal threshold for test positivity when testing deer sera for responses to Omicron variant B.1.1.529, compared to the 30 % inhibition recommended for ancestral variants
Ability of Strained C Atoms to act as an Electron Donor
No full textThere is a great deal of strain within the propellane and pyramidane hydrocarbon molecules. Quantum chemical calculations evaluate how this strain affects the ability of the bridgehead C atom to act as an electron donor in hydrogen, halogen, chalcogen, pnicogen, and tetrel bonds, despite the absence of a formal C lone pair or CC multiple bond. The strain induces the formation of a substantial region of negative electrostatic potential on this C atom which can attract the σ-hole of an electrophile. Each such molecule also contains an occupied molecular orbital that can be described as either a C lone pair or C–C bond, which is spatially disposed to align with, and transfer charge to, a σ* antibonding orbital of an approaching Lewis acid. The degree of strain within the hydrocarbon is closely correlated with the magnitude of the negative electrostatic potential, which is in turn connected with the strength of the ensuing bond. Tetrel bonds are strongest, followed by halogen, both of which contain a significant degree of covalency
Impact of Arctic and Antarctic Sudden Stratospheric Warmings on Thermospheric Composition
No full textUsing the Global‐scale Observations of the Limb and Disk (GOLD) and the Global Ultraviolet Imager (GUVI), we examine the impact of sudden stratospheric warmings (SSWs) on the changes of thermospheric composition during the 2018–2019 and 2020–2021 Arctic SSWs and the 2019 Antarctic SSW. Contributions of planetary waves, gravity waves, and migrating tides are assessed by performing numerical experiments with the NSF National Center for Atmospheric Research (NCAR) vertically extended version of the Whole Atmosphere Community Climate Model (WACCM‐X). The variations in the column integrated O and N2 density ratio (∑ O/N2) are generally similar among WACCM‐X, GOLD, and GUVI observations though some differences exist. Following the onset of the Arctic SSWs, ∑ O/N2 is reduced by ∼10% at low to mid latitudes. The variations during the 2019 Antarctic SSW are less pronounced, likely due to the event being a minor warming. WACCM‐X simulations, with the Kp index and F10.7 cm solar flux kept at fixed low levels, confirm that the variability of ∑ O/N2 at low to mid latitudes is primarily induced by SSWs. The ∑ O/N2 changes are associated with the reversals of the mean meridional circulation (MMC) in the lower thermosphere, mainly driven by westward‐traveling planetary waves. The results highlight that planetary wave activity during SSWs can significantly impact the mean state of the thermosphere