bluuebunny/crossref_metadata_2025_split huggingface dataset:
An intelligent system for monitoring students' engagement in large classroom teaching through facial expression recognition
Authors: Pabba Chakradhar , Kumar Praveen 
Published: October 2021

AbstractStudents' disengagement problem has become critical in the modern scenario due to various distractions and lack of student‐teacher interactions. This problem is exacerbated with large offline classrooms, where it becomes challenging for teachers to monitor students' engagement and maintain the right‐level of interactions. Traditional ways of monitoring students' engagement rely on self‐reporting or using physical devices, which have limitations for offline classroom use. Student's academic affective states (e.g., moods and emotions) analysis has potential for creating intelligent classrooms, which can autonomously monitor and analyse students' engagement and behaviours in real‐time. In recent literature, a few computer vision based methods have been proposed, but they either work only in the e‐learning domain or have limitations in real‐time processing and scalability for large offline classes. This paper presents a real‐time system for student group engagement monitoring by analysing their facial expressions and recognizing academic affective states: ‘boredom,’ ‘confuse,’ ‘focus,’ ‘frustrated,’ ‘yawning,’ and ‘sleepy,’ which are pertinent in the learning environment. The methodology includes certain pre‐processing steps like face detection, a convolutional neural network (CNN) based facial expression recognition model, and post‐processing steps like frame‐wise group engagement estimation. For training the CNN model, we created a dataset of the aforementioned facial expressions from classroom lecture videos and added related samples from three publicly available datasets, BAUM‐1, DAiSEE, and YawDD, to generalize the model predictions. The trained model has achieved train and test accuracy of 78.70% and 76.90%, respectively. The proposed methodology gave promising results when compared with self‐reported engagement levels by students.
Liana optical traits increase tropical forest albedo and reduce ecosystem productivity
Authors: Meunier Félicien , Visser Marco D. , Shiklomanov Alexey , Dietze Michael C. , Guzmán Q. J. Antonio , Sanchez‐Azofeifa G. Arturo , De Deurwaerder Hannes P. T. , Krishna Moorthy Sruthi M. , Schnitzer Stefan A. , Marvin David C. , Longo Marcos , Liu Chang , Broadbent Eben N. , Almeyda Zambrano Angelica M. , Muller‐Landau Helene C. , Detto Matteo , Verbeeck Hans 
Published: October 2021

AbstractLianas are a key growth form in tropical forests. Their lack of self‐supporting tissues and their vertical position on top of the canopy make them strong competitors of resources. A few pioneer studies have shown that liana optical traits differ on average from those of colocated trees. Those trait discrepancies were hypothesized to be responsible for the competitive advantage of lianas over trees. Yet, in the absence of reliable modelling tools, it is impossible to unravel their impact on the forest energy balance, light competition, and on the liana success in Neotropical forests. To bridge this gap, we performed a meta‐analysis of the literature to gather all published liana leaf optical spectra, as well as all canopy spectra measured over different levels of liana infestation. We then used a Bayesian data assimilation framework applied to two radiative transfer models (RTMs) covering the leaf and canopy scales to derive tropical tree and liana trait distributions, which finally informed a full dynamic vegetation model. According to the RTMs inversion, lianas grew thinner, more horizontal leaves with lower pigment concentrations. Those traits made the lianas very efficient at light interception and significantly modified the forest energy balance and its carbon cycle. While forest albedo increased by 14% in the shortwave, light availability was reduced in the understorey (−30% of the PAR radiation) and soil temperature decreased by 0.5°C. Those liana‐specific traits were also responsible for a significant reduction of tree (−19%) and ecosystem (−7%) gross primary productivity (GPP) while lianas benefited from them (their GPP increased by +27%). This study provides a novel mechanistic explanation to the increase in liana abundance, new evidence of the impact of lianas on forest functioning, and paves the way for the evaluation of the large‐scale impacts of lianas on forest biogeochemical cycles.
Responses of soil pH to no‐till and the factors affecting it: A global meta‐analysis
Authors: Zhao Xin , He Cong , Liu Wen‐Sheng , Liu Wen‐Xuan , Liu Qiu‐Yue , Bai Wei , Li Li‐Jun , Lal Rattan , Zhang Hai‐Lin 
Published: October 2021

AbstractNo‐till (NT) is a sustainable option because of its benefits in controlling erosion, saving labor, and mitigating climate change. However, a comprehensive assessment of soil pH response to NT is still lacking. Thus, a global meta‐analysis was conducted to determine the effects of NT on soil pH and to identify the influential factors and possible consequences based on the analysis of 114 publications. When comparing tillage practices, the results indicated an overall significant decrease by 1.33 ± 0.28% in soil pH under NT than that under conventional tillage (p < .05). Soil texture, NT duration, mean annual temperature (MAT), and initial soil pH are the critical factors affecting soil pH under NT. Specifically, with significant variations among subgroups, when compared to conventional tillage, the soil under NT had lower relative changes in soil pH observed on clay loam soil (−2.44%), long‐term implementation (−2.11% for more than 15 years), medium MAT (−1.87% in the range of 8–16℃), neutral soil pH (−2.28% for 6.5 < initial soil pH < 7.5), mean annual precipitation (−1.95% in the range of 600–1200 mm), in topsoil layers (−2.03% for 0–20 cm), with crop rotation (−1.98%), N fertilizer input (the same for NT and conventional tillage) of 100–200 kg N ha−1 (−1.83%), or crop residue retention (−1.52%). Changes in organic matter decomposition under undisturbed soil and with crop residue retention might lead to a higher concentration of H+ and lower of basic cations (i.e., calcium, magnesium, and potassium), which decrease the soil pH, and consequently, impact nutrient dynamics (i.e., soil phosphorus) in the surface layer under NT. Furthermore, soil acidification may be aggravated by NT within site‐specific conditions and improper fertilizer and crop residue management and consequently leading to adverse effects on soil nutrient availability. Thus, there is a need to identify strategies to ameliorate soil acidification under NT to minimize the adverse consequences.
Land use intensification increasingly drives the spatiotemporal patterns of the global human appropriation of net primary production in the last century
Authors: Kastner Thomas , Matej Sarah , Forrest Matthew , Gingrich Simone , Haberl Helmut , Hickler Thomas , Krausmann Fridolin , Lasslop Gitta , Niedertscheider Maria , Plutzar Christoph , Schwarzmüller Florian , Steinkamp Jörg , Erb Karl‐Heinz 
Published: October 2021

AbstractLand use has greatly transformed Earth's surface. While spatial reconstructions of how the extent of land cover and land‐use types have changed during the last century are available, much less information exists about changes in land‐use intensity. In particular, global reconstructions that consistently cover land‐use intensity across land‐use types and ecosystems are missing. We, therefore, lack understanding of how changes in land‐use intensity interfere with the natural processes in land systems. To address this research gap, we map land‐cover and land‐use intensity changes between 1910 and 2010 for 9 points in time. We rely on the indicator framework of human appropriation of net primary production (HANPP) to quantify and map land‐use‐induced alterations of the carbon flows in ecosystems. We find that, while at the global aggregate level HANPP growth slowed down during the century, the spatial dynamics of changes in HANPP were increasing, with the highest change rates observed in the most recent past. Across all biomes, the importance of changes in land‐use areas has declined, with the exception of the tropical biomes. In contrast, increases in land‐use intensity became the most important driver of HANPP across all biomes and settings. We conducted uncertainty analyses by modulating input data and assumptions, which indicate that the spatial patterns of land use and potential net primary production are the most critical factors, while spatial allocation rules and uncertainties in overall harvest values play a smaller role. Highlighting the increasing role of land‐use intensity compared to changes in the areal extent of land uses, our study supports calls for better integration of the intensity dimension into global analyses and models. On top of that, we provide important empirical input for further analyses of the sustainability of the global land system.
Temperature sensitivity of anaerobic methane oxidation versus methanogenesis in paddy soil: Implications for the CH4 balance under global warming
Authors: Fan Lichao , Dippold Michaela A. , Thiel Volker , Ge Tida , Wu Jinshui , Kuzyakov Yakov , Dorodnikov Maxim 
Published: October 2021

AbstractThe global methane (CH4) budget is based on a sensitive balance between methanogenesis and CH4 oxidation (aerobic and anaerobic). The response of these processes to climate warming, however, is not quantified. This largely reflects our lack of knowledge about the temperature sensitivity (Q10) of the anaerobic oxidation of CH4 (AOM)—a ubiquitous process in soils. Based on a 13CH4 labeling experiment, we determined the rate, Q10 and activation energy of AOM and of methanogenesis in a paddy soil at three temperatures (5, 20, 35°C). The rates of AOM and of methanogenesis increased exponentially with temperature, whereby the AOM rate was significantly lower than methanogenesis. Both the activation energy and Q10 of AOM dropped significantly from 5–20 to 20–35°C, indicating that AOM is a highly temperature‐dependent microbial process. Nonetheless, the Q10 of AOM and of methanogenesis were similar at 5–35°C, implying a comparable temperature dependence of AOM and methanogenesis in paddy soil. The continuous increase of AOM Q10 over the 28‐day experiment reflects the successive utilization of electron acceptors according to their thermodynamic efficiency. The basic constant for Q10 of AOM was calculated to be 0.1 units for each 3.2 kJ mol−1 increase of activation energy. We estimate the AOM in paddy soils to consume 2.2~5.5 Tg CH4 per year on a global scale. Considering these results in conjunction with literature data, the terrestrial AOM in total consumes ~30% of overall CH4 production. Our data corroborate a similar Q10 of AOM and methanogenesis. As the rate of AOM in paddy soils is lower than methanogenesis, however, it will not fully compensate for an increased methane production under climate warming.
Quantitatively monitoring the resilience of patterned vegetation in the Sahel
Authors: Buxton Joshua E. , Abrams Jesse F. , Boulton Chris A. , Barlow Nick , Rangel Smith Camila , Van Stroud Samuel , Lees Kirsten J. , Lenton Timothy M. 
Published: October 2021

AbstractPatterning of vegetation in drylands is a consequence of localized feedback mechanisms. Such feedbacks also determine ecosystem resilience—i.e. the ability to recover from perturbation. Hence, the patterning of vegetation has been hypothesized to be an indicator of resilience, that is, spots are less resilient than labyrinths. Previous studies have made this qualitative link and used models to quantitatively explore it, but few have quantitatively analysed available data to test the hypothesis. Here we provide methods for quantitatively monitoring the resilience of patterned vegetation, applied to 40 sites in the Sahel (a mix of previously identified and new ones). We show that an existing quantification of vegetation patterns in terms of a feature vector metric can effectively distinguish gaps, labyrinths, spots, and a novel category of spot–labyrinths at their maximum extent, whereas NDVI does not. The feature vector pattern metric correlates with mean precipitation. We then explored two approaches to measuring resilience. First we treated the rainy season as a perturbation and examined the subsequent rate of decay of patterns and NDVI as possible measures of resilience. This showed faster decay rates—conventionally interpreted as greater resilience—associated with wetter, more vegetated sites. Second we detrended the seasonal cycle and examined temporal autocorrelation and variance of the residuals as possible measures of resilience. Autocorrelation and variance of our pattern metric increase with declining mean precipitation, consistent with loss of resilience. Thus, drier sites appear less resilient, but we find no significant correlation between the mean or maximum value of the pattern metric (and associated morphological pattern types) and either of our measures of resilience.
Differences in instrumental activities of daily living between mild cognitive impairment and Alzheimer's disease: A study using a detailed executive function assessment
Authors: Maeshima Shinichiro , Osawa Aiko , Kondo Izumi , Kamiya Masaki , Ueda Ikue , Sakurai Takashi , Arai Hidenori 
Published: October 2021

AimExecutive dysfunction is pathognomonic for dementia and impedes the activities of daily living (ADL). This study aimed to examine the relationship of dementia severity with executive dysfunction and ADL in mild cognitive impairment and dementia.MethodsThis single‐center study enrolled 86 patients (men, 40; women, 46; mean age, 76.1 ± 7.5 years) referred for cognitive and physical rehabilitation between October 2015 and September 2020. The Clinical Dementia Rating (CDR) was 0.5, 1, and ≥2 in 45, 30, and 11 patients, respectively. The presence and severity of executive dysfunction were assessed using the Behavioral Assessment of the Dysexecutive Syndrome–Japanese version (BADS). The ADL and instrumental ADL (IADL) were assessed using the Barthel Index and Frenchay Activities Index (FAI), respectively. We examined the relationship between CDR severity and overall BADS profile score and its sub‐items, and that between the overall BADS profile score and IADL.ResultsThe cognitive and executive functional assessment scores differed significantly depending on the CDR severity. The CDR severity and overall BADS profile score exhibited significant correlations. The BADS found cognitive impairment in 31%, 70%, and 100% of patients with CDR0.5, CDR1, and CDR≥2, respectively.The FAI score differed according to the CDR severity in women but not in men. The overall profile and age‐adjusted BADS scores were strongly correlated with the IADL in women but not in men.ConclusionsThe greater the severity of executive dysfunction, the greater the difficulty in performing ADL. This effect was more pronounced in women and may predict dementia progression. Geriatr Gerontol Int 2021; 21: 1111–1117.
Synthesis mechanism and phase stability analysis of z‐Y2Si2O7 by sol‐gel process
Authors: Ma Qin , Yang Jinshan , Xue Yudong , Hu Jianbao , Zhang Xiangyu , Dong Shaoming 
Published: October 2021

AbstractSynthesis mechanism and phase stability analysis of square z‐Y2Si2O7 was studied in this research by using Y(NO3)3·6H2O and tetra ethoxy orthosilicate as precursors. The concentration of the precursor directly affects the degree of hydrolysis of tetra ethoxy orthosilicate and the uniformity of the gel by Fourier transform infrared spectral analysis. The thermogravimetric analysis shows that the crystallization temperature of the precursor decreases gradually with the decrease of precursor concentration. Because the low precursor concentration is beneficial to the formation of the homogeneous molecular level of yttrium silica network gel. Finally, the crystallized z‐Y2Si2O7 was detected by X‐ray diffraction and further verified by a transmission electron microscope after calcining at 800°C. The maximum stable temperature of z‐Y2Si2O7 was less than 1050°C. The microscopic morphology of z‐Y2Si2O7 is square nanoparticles. The grain size of z‐Y2Si2O7 increases with the decrease of precursor concentration.
The impact of environmental policy on wage inequality
Authors: Kuo Kuo‐Hsing , Wu Shang‐Fen , Lee Cheng‐Te 
Published: October 2021

AbstractConsider a small open Harris and Todaro's model. This paper analyzes the impact of the policy of environmental protection on skilled–unskilled wage inequality. We find that, in the economy with urban unemployment, if the elasticity of substitution between unskilled labor and pollution in the urban low‐skill sector is small (large) enough then a rise in the pollution tax will expand (narrow down) skilled–unskilled wage inequality. In addition, we prove that, in the economy with full employment, a rise in the pollution tax will raise the skilled–unskilled wage inequality, if the elasticity of substitution between unskilled labor and pollution is larger than that between capital and pollution in the urban low‐skill sector.
Merger under horizontal and vertical product differentiation
Authors: Sen Neelanjan , Narula Drishti 
Published: October 2021

AbstractThis paper studies the possibility of a merger when firms are asymmetric in marginal costs and produce vertically and horizontally differentiated products. The merger of two firms that produce the better‐quality products (w.r.t. third firm) is possible, if the quality difference (net of cost) or the horizontal product differentiation between the firms that merge is high. If the quality difference (net of cost) between the merged firms and the non‐merged firm increases, then a merger is possible if the quality difference (net of cost) and the horizontal product differentiation of the merged firms are significantly high.
Metabolomics in early life and the association with body composition at age 2 years
Authors: van Beijsterveldt Inge A.L.P. , Snowden Stuart G. , Myers Pernille Neve , de Fluiter Kirsten S. , van de Heijning Bert , Brix Susanne , Ong Ken K. , Dunger David B. , Hokken‐Koelega Anita C.S. , Koulman Albert 
Published: October 2021

SummaryBackground and ObjectivesEarly life is a critical window for adiposity programming. Metabolic‐profile in early life may reflect this programming and correlate with later life adiposity. We investigated if metabolic‐profile at 3 months of age is predictive for body composition at 2 years and if there are differences between boys and girls and between infant feeding types.MethodsIn 318 healthy term‐born infants, we determined body composition with skinfold measurements and abdominal ultrasound at 3 months and 2 years of age. High‐throughput‐metabolic‐profiling was performed on 3‐month‐blood‐samples. Using random‐forest‐machine‐learning‐models, we studied if the metabolic‐profile at 3 months can predict body composition outcomes at 2 years of age.ResultsPlasma metabolite‐profile at 3 months was found to predict body composition at 2 years, based on truncal: peripheral‐fat‐skinfold‐ratio (T:P‐ratio), with a predictive value of 75.8%, sensitivity of 100% and specificity of 50%. Predictive value was higher in boys (Q2 = 0.322) than girls (Q2 = 0.117). Of the 15 metabolite variables most strongly associated with T:P‐ratio, 11 were also associated with visceral fat at 2 years of age.ConclusionSeveral plasma metabolites (LysoPC(22:2), dimethylarginine and others) at 3 months associate with body composition outcome at 2 years. These results highlight the importance of the first months of life for adiposity programming.
The association between early country‐level COVID‐19 testing capacity and later COVID‐19 mortality outcomes
Authors: Kannoth Sneha , Kandula Sasikiran , Shaman Jeffrey 
Published: October 2021

AbstractBackgroundThe COVID‐19 pandemic has overrun hospital systems while exacerbating economic hardship and food insecurity on a global scale. In an effort to understand how early action to find and control the virus is associated with cumulative outcomes, we explored how country‐level testing capacity affects later COVID‐19 mortality.MethodsWe used the Our World in Data database to explore testing and mortality records in 27 countries from December 31, 2019, to September 30, 2020; we applied Cox proportional hazards regression to determine the relationship between early COVID‐19 testing capacity (cumulative tests per case) and later COVID‐19 mortality (time to specified mortality thresholds), adjusting for country‐level confounders, including median age, GDP, hospital bed capacity, population density, and nonpharmaceutical interventions.ResultsHigher early testing implementation, as indicated by more cumulative tests per case when mortality was still low, was associated with a lower risk for higher per capita deaths. A sample finding indicated that a higher cumulative number of tests administered per case at the time of six deaths per million persons was associated with a lower risk of reaching 15 deaths per million persons, after adjustment for all confounders (HR = 0.909; P = 0.0001).ConclusionsCountries that developed stronger COVID‐19 testing capacity at early timepoints, as measured by tests administered per case identified, experienced a slower increase of deaths per capita. Thus, this study operationalizes the value of testing and provides empirical evidence that stronger testing capacity at early timepoints is associated with reduced mortality and improved pandemic control.
Comparative analysis of COVID‐19 case fatality rate between two waves in Nepal
Authors: GC Sulochan , Khanal Ashok , Paudel Atmika , GC Vijay S. , Khanal Aashis , Panthee Suresh 
Published: October 2021

AbstractThe first COVID‐19 case in Nepal was reported on January 23, 2020. Then infection, then, started to spread gradually, and October marked the most devastating increase in COVID‐19 cases of the year 2020. Compared with the October 2020 peak in Nepal, the May 2021 peak of COVID‐19 observed 2‐ and 10‐fold rise in new cases and deaths per day, respectively. Given that this surprising increase in the death rate was not observed in other countries, this study analyzed the COVID‐19 case fatality rates between the two peaks in Nepal. We found an increase in death rates among younger adults and people without comorbidities.
A scoping review of research on well‐being across diverse family structures: Rethinking approaches for understanding contemporary families
Authors: Jensen Todd M. , Sanner Caroline 
Published: October 2021

AbstractIn the United States and across the globe, demographic trends have coalesced to produce an increasingly diverse set of family structures, fueling international interest in exploring diverse family structures as key developmental contexts for adults and children. Given the persistence of research focused on well‐being differences across family structures, and in order to move this research into the future productively, it is critical to rigorously chart and evaluate how this research is being conducted. In this scoping review, we evaluate 283 studies that examined associations between family structure and well‐being. We reflect on dominant methodological trends across four primary domains: (a) approaches to measuring family structure, (b) approaches to analyzing associations between family structure and well‐being, (c) the application of theory, and (d) conceptualizations of well‐being. In evaluating observable trends, we offer recommendations for rethinking where we can (and perhaps should) go next to better understand and support contemporary families.