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The marine biological pump is crucial for removing excess carbon dioxide from the atmosphere to the ocean interior and seafloor sediments. The Late Miocene Biogenic Bloom (LMBB), marked by notable increases in biogenic components in marine sediments, provides insights into the response of the biological pump to climate change. However, understanding the timing, distribution, and cause of the LMBB remains limited. We use marine barite, a refractory mineral precipitating from the water column associated with carbon export, and other proxies to reconstruct productivity in the equatorial Indian Ocean and equatorial western Atlantic between 12 and 5 Ma. Multi‐proxy records reveal the onset of the LMBB in the equatorial Indian Ocean at ∼9 Ma, primarily driven by more vigorous upwelling during global cooling. We suggest that the steepened meridional temperature gradient and the Antarctic ice sheet expansion have strengthened ocean overturning, facilitating nutrient supply and biogenic bloom in upwelling regions. Plain Language Summary: The late Miocene (11.6–5.33 Ma), with an atmospheric CO2 concentration similar to the pre‐industrial level, represents an ideal time window for understanding the relationship between anthropogenic climate, ocean circulation, and global carbon cycling. During this time interval, biogenic components in marine sediments have increased significantly, which is known as the Late Miocene Biogenic Bloom (LMBB). However, due to the limitations of traditional productivity proxies (e.g., biogenic calcium carbonate, biogenic silica), the temporal and spatial distributions of this event remain controversial. In this study, we use marine barite accumulation rate as a reliable tracer of the LMBB, as marine barite precipitating from the water column is closely associated with export productivity and has very low solubility. Our new barite records from two low‐latitude sites inside and outside an upwelling regime suggest that the LMBB has commenced at ∼9 Ma in the equatorial Indian Ocean but has not occurred or sustained in the equatorial western Atlantic. By compiling sea‐surface temperature and multi‐proxy data, we attribute the LMBB to intensified ocean overturning under global cooling. The enhanced biological productivity, fueled by nutrient supply from upwelling, provides positive feedback to the late‐Miocene climate cooling. Key Points: Marine barite provides new insight into the Late Miocene Biogenic BloomMulti‐proxy records show inconsistent productivity changes in the equatorial Indian Ocean and equatorial western Atlantic OceanLate‐Miocene cooling strengthens ocean overturning and nutrient supply to the surface, driving biogenic bloom in upwelling regions [ABSTRACT FROM AUTHOR]

Background/objective: To examine the cognitive benefits of 6  months of prescribed intermittent exercise (10-min bouts totaling 150 weekly minutes) in community-dwelling older adults, comparing effects of low-intensity movement (LIM) and moderate-intensity aerobic exercise (aerobic exercise; AE) training; and exploring biological mechanisms of exercise-related cognitive improvement. Method: Twenty-five adults (>60  years old) participated in a 6-month controlled trial and were randomized into LIM or AE intermittent training. Cognition was assessed using a neuropsychological test battery including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), California Verbal Learning Test, 2nd Edition (CVLT-II), and Delis-Kaplan Executive Function System (D-KEFS). Neuroimaging measures were collected using a 7  T human MRI scanner. Serologic neurotrophic and inflammatory factors were analyzed using Luminex multiplex assays [brain derived neurotrophic factor (BDNF); vascular endothelial growth factor (VEGF)]; interleukin-6 (IL-6), C-reactive protein (CRP), plasminogen activator inhibitor (PAI-1). Results: LIM and AE intermittent training had dissociable effects on cognition, with LIM resulting in improved learning and memory and AE resulting in improved executive functioning. Intervention groups differed on change in cognitive performance on CVLT-II learning and D-KEFS trail making test. Increase in right dorsolateral prefrontal cortex (DLPFC) surface area was linked to executive improvement (i.e., phonemic fluency) regardless of intervention group. A decline in circulating PAI-1 was linked to learning and memory improvement in response to LIM over 6 months. Conclusion: Moderate-intensity AE and LIM intermittent training likely have distinct cognitive benefits, though low-intensity activity is often included as a control group in exercise trials in aging. [ABSTRACT FROM AUTHOR]

The isotopic composition of barium ^[sup 138]Ba) has emerged as a powerful tracer of deep-ocean circulation, water mass provenance, and the oceanic Ba cycle. Although the δ[sup 138]Ba of water masses is primarily controlled by the balance between pelagic barite precipitation and Ba resupply from ocean circulation, questions remain regarding the isotopic offset associated with pelagic barite formation and how the resultant Ba isotope compositions are transmitted through the water column to marine sediments. To address these questions, we conducted a time series study of dissolved, particulate, and sedimentary Ba chemistry in the Gulf of Aqaba (GOA), in the northern Red Sea, from January 2015 to April 2016. These data span significant seasonal changes in hydrography, primary productivity, and aerosol deposition, revealing three principal findings. First, the dissolved Ba chemistry of the GOA is vertically uniform across the time series, largely reflecting water mass advection from the Red Sea, with mean dissolved Ba concentrations of 47.9 ± 4.7 nmol kg[sup -1] and mean δ[sup 13ί]^ = +0.55%" ± 0.07%" (±2 SD, n = 18). Second, despite significant variations in particulate matter composition and flux, the δ[sup 138]Ba of sinking particulate Ba maintained a consistent isotope composition across different depths and over time at +0.09% ± 0.06% (n = 26). Consequently, these data imply a consistent Ba isotope offset of -0.46% ± 0.10% (±2 SD) between sinking particulates and seawater. This offset is similar to those determined in previous studies and indicates that it applies to particulates formed across diverse environmental conditions. Third, barite-containing sediment samples deposited in the GOA exhibit δ[sup 13ί]^ = +0.34% ± 0.03%, which is offset by approximately +0.2% relative to sinking particles. While the specific mechanism driving this offset remains unresolved, our results highlight the importance of performing site-specific proxy validations and exercising careful site selection when applying novel paleoceanographic proxies. [ABSTRACT FROM AUTHOR]

Virtual reality (VR) is an innovative technology that immerses users within its environment, holding significant potential across various sectors, including education. Developing a VR-based application in the form of a game for educational purposes necessitates a usability evaluation. This study aims to develop and evaluate usability of a VR game, CT Saber, designed explicitly for learning computational thinking (CT). The name CT Saber is inspired by the popular VR game Beat Saber, with 'CT' denoting computational thinking to emphasize the educational focus of the game. The research employed a Design and Development Research (DDR) approach, encompassing four stages: analysis & definition, design, development, and evaluation. To assess the usability of CT Saber, pilot testing was carried out involving 36 participants (24 male, 12 female) of computer science students aged between 19-22 years. The USE Questionnaire framework was used to evaluate usability, consisting of four variables: usefulness, ease of use, ease of learning, and satisfaction. The evaluation revealed that CT Saber is categorized as 'acceptable' from dichotomous and conventional academic grading perspectives. Similarly, a multiple linear regression analysis confirmed that the independent variables (usefulness, ease of use, and ease of learning) together significantly (p < 0.01) influence the dependent variable (satisfaction). However, only usefulness significantly influences satisfaction. Responses to open-ended questions in the questionnaire also indicated predominantly positive feedback from most participants. Consequently, it can be concluded that the CT Saber VR game developed in this study successfully meets the established criteria for usability. [ABSTRACT FROM AUTHOR]

As technological advancements shape the workforce, computational thinking skills (CTS) are becoming increasingly crucial. The objective of the study is to explore the potential mediating role of professional development and career planning in the association between robotic coding and software and computational thinking. The study selected 308 youths using simple random sampling and the collected data was subjected to structural equation modelling (SEM) and confirmatory factor analysis (CFA) using SmartPLS. Additionally, demographic data were analyzed using statistical package for social sciences (SPSS). The results concluded that the instrument adopted fulfilled the requirements and was valid for measuring CTS. This indicates that the instrument effectively assessed the participants’ proficiency in CTS. The findings of this study have implications for addressing the skills gaps among youths. The outcomes of this research can aid in designing educational interventions and policies that focus on developing computational thinking skills among new graduates. By fostering these skills, youths can better adapt to the demands of the rapidly evolving technological landscape and contribute effectively to the industries and job market influenced by industry 4.0. Further research on longitudinal studies may be beneficial to assess the long-term impact of CTS development initiatives on reducing skills gaps and ensuring youths are equipped for future workforce requirements [ABSTRACT FROM AUTHOR]

Lifestyle factors, such as diet and sleep quality, are receiving increasing interest as accessible therapeutic approaches to migraine. The Mediterranean diet (MD) has shown clear benefits in cardiovascular and metabolic diseases, as well as in sleep patterns. Here, our objective was to identify the impact of adherence to the MD and other lifestyle factors on the clinical burden of migraine. For this purpose, we enrolled 170 migraine patients and 100 controls, assessing the clinical disability of headache using standardized clinical scales (HIT-6 and MIDAS) in the migraineur cohort and lifestyle patterns in both groups through the PREDIMED score for MD adherence, the IPAQ scale for physical activity, and BMI. Subjects were also screened for sleep–wake disturbances based on the Pittsburgh Sleep Quality Index (PSQI). We found that migraine patients had lower adherence to the MD compared to the controls and that the HIT-6 scale had a significant negative relationship with MD adherence in patients with high-frequency episodic and chronic migraine. Additionally, in the same migraine patients, the presence of sleep–wake disturbances was correlated with greater migraine disability as assessed by the MIDAS score. In conclusion, this study found that among different lifestyle factors, poor adherence to the MD and the presence of sleep–wake disturbances were closely associated with migraine disability and chronification. [ABSTRACT FROM AUTHOR]

Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Assuming that there is an a priori agreement between processes on the names of shared memory locations, as is done in almost all the publications on concurrent shared memory algorithms, is tantamount to assuming that agreement has already been solved at a lower level. It is intriguing to figure out how coordination can be achieved without relying on such lower-level agreement. To better understand the new model, we first design new algorithms for several important problems, such as mutual exclusion, consensus, election, and renaming. Then, we prove space lower bounds, impossibility results, and resolve two foundational long-standing open problems in the context of anonymous memory systems. Using these results, we identify fundamental differences between the standard shared memory model and the strictly weaker anonymous shared memory model. Besides enabling us to understand better the intrinsic limits for coordinating the actions of asynchronous processes, the new model has been shown to be useful in modeling biologically inspired distributed computing methods, especially those based on ideas from molecular biology. [ABSTRACT FROM AUTHOR]

Climate change is altering the distribution and abundance of marine species, especially in Arctic and sub‐Arctic regions. In the eastern Bering Sea, home of the world's largest run of sockeye salmon (Oncorhynchus nerka), juvenile sockeye salmon abundance has increased and their migration path shifted north with warming, 2002–2018. The reasons for these changes are poorly understood. For these sockeye salmon, we quantify environmental and biological covariate effects within spatio‐temporal species distribution models. Spatio‐temporally, with respect to juvenile sockeye salmon densities: (1) sea surface temperature had a nonlinear effect, (2) large copepod, Calanus, a minor prey item, had no effect, (3) age‐0 pollock (Gadus chalcogrammus), a major prey item during warm years, had a positive linear effect, and (4) juvenile pink salmon (O. gorbuscha) had a positive linear effect. Temporally, annual biomass of juvenile sockeye salmon was nonlinearly related to sea temperature and positively related to age‐0 pollock and juvenile pink salmon abundance. Results indicate that sockeye salmon distributed with and increased in abundance with increases in prey, and reached a threshold for optimal temperatures in the eastern Bering Sea. Changes in population dynamics and distribution of sockeye salmon in response to environmental variability have potential implications for projecting specific future food securities and management of fisheries in Arctic waters. [ABSTRACT FROM AUTHOR]

This study focuses on developing and validating instruments to assess the computational thinking skills (CTS) and collaboration skills (CS) of undergraduate students in Indonesia. Employing a quantitative research approach with the exploratory factor analysis (EFA) technique, the research process unfolded in three validation steps. First, face validity was established through expert judgment. Second, discriminant validity was examined using product-moment correlations and Cronbach's alpha. Finally, EFA were employed to assess the factorial structure. The instrument development process followed five phases: drafting the instrument, face validity assessment by experts, data collection involving 242 undergraduate students as samples, discriminant validity analysis (product moment and Cronbach's alpha), and EFA analysis to group items and construct dimensions. This study identified six dimensions for CTS (algorithmic thinking, cooperative thinking, problem reformulation, creativity, critical thinking, and systematic testing) and three dimensions for CS (knowledge sharing, planning, and responsibility). These findings support validating the CTS and CS self-assessment scale, making it a valuable tool for evaluating undergraduate student learning and researching computational thinking and CS in Indonesia. Researchers and educators are encouraged to utilize the CTS and CS instrument for self-assessment purposes and further exploration of these competencies among undergraduate students. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) has emerged as a pivotal technology for enhancing national and industrial competitiveness in the digital transformation era. Consequently, the cultivation of specialized talent in AI has garnered significant attention. This study analyzed AI-related department curricula at major universities worldwide, identifying critical courses for each academic semester. The data we collected included course titles, syllabi, and learning objectives, which were refined and analyzed afterward. Furthermore, we comparatively examined university AI education programs based on the content of Computer Science Curricula 2023, a widely recognized framework for computer science education. The insights gleaned from our analysis revealed that AI curricula are built upon a foundation of computer science, emphasizing the importance of a deep understanding of various related domains within the field of computer science. Based on these findings, we proposed a curriculum for AI departments, considering the need for a comprehensive understanding of computer science alongside specialized AI courses. This study aims to provide foundational data for advancing AI education and guide educational program improvements. Ultimately, it aspires to contribute to developing specialized professionals in the AI field, thereby bolstering national and industrial competitiveness in the rapidly evolving digital landscape. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive overview of computational thinking (CT) research trends in mathematics learning from 2009 to 2023. To reach this aim, a bibliometric approach was used in this study to analyze the publication distribution pattern on CT focused on the following categories: research development, the most productive journals and countries, highly cited references, topic network, and thematic evolution map. A total of 276 articles retrieved from the Scopus database were analyzed and visualized through the Bibliometrix analysis package from R and VOSviewer software. The finding shows that since 2009, CT has been the subject of mathematics learning research, which has grown significantly since 2013. Regarding total publication in CT, Education and Information Technologies contributes as the most productive journal, and the United States places first among all countries. The article 'computational thinking' appears as the most widely referenced source. Moreover, the frequent topics network with CT are the integration of CT with programming, STEM, and coding. This result is analyzed further by the thematic evolution map showing CT research in STEM education, including mathematics, exhibits promising prospects for future development. [ABSTRACT FROM AUTHOR]

The network of any IT system is subject to continuous changes, such as the addition of new nodes, software installations, and the emergence of new vulnerabilities. On the other hand, the importance of nodes within the IT system’s network varies due to various factors, impacting the severity of potential node exploitation. Additionally, the interconnected nature of the nodes means that the security of each node is interdependent on the others nodes. In this context, effective risk assessment methodologies that consider the factors which impact the security of the system are crucial. This paper introduces an innovative methodology that takes into account the aforementioned factors. The proposed approach evaluates vulnerabilities, interconnections, and dynamic changes to deliver a comprehensive and up-to-date security risk assessment. By employing this methodology, administrators gain better control over system security with dynamic evaluations that support wellinformed decisions. Furthermore, the methodology facilitates risk assessment for specific nodes and enables the quantification of their security levels. Due to a thorough assessment, the proposed methodology empowers IT administrators to improve the overall security of the system. [ABSTRACT FROM AUTHOR]

Software architecture security design is a key stage in developing business-oriented system, such as business-critical system, ICT system and AI system. Many typical accidents also remind us that the security of software architecture even plays a more important role than the code security in most software systems. However, there are very few researches which focus on the security of software architecture. Especially, we don't find a systematic and feasible quantitative method to evaluate the security of software architecture. To fill this gap, we launched a research project focusing on software architecture security since 2019 and try to provide a series of quantitative methods for evaluating the security of software architecture. In this paper, a business-oriented quantitative method was proposed to evaluate the security of software architecture from the view of business-critical security insurance. In our method, both business dependency graph (BDG) and multi-hierarchical dependency graph (MHDG) are defined and constructed first for describing businesses and their relationships, and system components and their relationships; then, attack points and business key-points are identified and labeled on BDG and MHDG; and further, all potential attack paths and effective attack paths in the system based on MHDG are detected; and finally, a set of security indicators is defined and used to evaluate the security of software architecture quantitatively. For more effective experiments, we use software architectures with different styles and different evolution versions. Experimental results show that our method can reflect effectively the security characteristics of software architecture with different styles, can find the security changes of different architecture evolution versions for the same system, and can perform quantitative evaluation of software architecture security efficiently. [ABSTRACT FROM AUTHOR]

The rapid advancement of Artificial Intelligence (AI) technology has brought about significant positive changes across society. However, it has also introduced challenges like privacy breaches, data bias, and spreading fake news. In response, several countries, including South Korea, have provided ethical guidelines and policies for AI. Yet, these measures often fall short of keeping pace with the speed and diversity of AI development. To address these issues, this study developed a comprehensive approach by integrating ethical considerations into AI education, covering the entire AI technology development and application process. It involved analyzing previous research on AI and AI ethics education and creating a draft of an integrated AI education program focused on problem-solving based on computational thinking and ethical practicality. The draft was refined and supplemented through two rounds of expert Delphi surveys, ultimately leading to an "Integrated AI Education Program." This proposed program emphasizes that the knowledge content of AI technology and ethical considerations should not be treated separately but addressed together. It aims to enhance moral and social capacities alongside the experience of thinking like a computer scientist when solving real-life problems. Through this, the program supports the ultimate goal of AI education: to foster computational thinking while providing an educational experience that considers both technology and ethics. This study is expected to advance the discussion on integrating AI ethics into AI education curricula and contribute to developing socially responsible AI developers and users. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Animal & Poultry Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper investigated the effect of online Scratch activities on college students’ computational and creative thinking. The study adopted a mixed research design including one group pretest-posttest. The sample consisted of 24 child development undergraduates (23 female and 1 male) in the 2019- 2020 academic year. The research was carried out in “Teaching science and mathematics in preschool education” course and lasted 12 weeks. The participants developed Scratch projects based on eight learning outcomes (four math and four science). Data were collected using the Computational Thinking Scale, the Marmara Creative Thinking Dispositions Scale, and reflective journals. The quantitative data were analyzed using a paired sample t-test. The qualitative data were analyzed using content analysis. The results showed that Scratch activities helped students develop computational and creative thinking. The results of this study provide evidence that Scratch activities develop the students’ higher order skills. Ultimately, this research study recommends that Scratch activities ought to be integrated to science and mathematics education curriculums. [ABSTRACT FROM AUTHOR]

Letter-to-letter transducers are a standard formalism for modeling reactive systems. Often, two transducers that model similar systems differ locally from one another, by behaving similarly, up to permutations of the input and output letters within "rounds". In this work, we introduce and study notions of simulation by rounds and equivalence by rounds of transducers. In our setting, words are partitioned to consecutive subwords of a fixed length k, called rounds. Then, a transducer T1 is k-round simulated by transducer T2 if, intuitively, for every input word x, we can permute the letters within each round in x, such that the output of T2 on the permuted word is itself a permutation of the output of T1 on x. Finally, two transducers are k-round equivalent if they simulate each other. We solve two main decision problems, namely whether T2 k-round simulates T1 (1) when k is given as input, and (2) for an existentially quantified k. We demonstrate the usefulness of the definitions by applying them to process symmetry: a setting in which a permutation in the identifiers of processes in a multi-process system naturally gives rise to two transducers, whose k-round equivalence corresponds to stability against such permutations. [ABSTRACT FROM AUTHOR]

Aims: To investigate loneliness, depression and sleep quality in patients with Type 2 Diabetes (T2DM) and to examine the mediating role of depression between loneliness and sleep quality among this group of patients with T2DM. Design: A cross‐sectional study. Methods: A group of T2DM patients was recruited from a tertiary hospital affiliated with a university in Wuhu City, Anhui Province from May to October 2021 by convenient sampling. Pearson correlation analysis and structural equation modelling were used for data analysis in this study. Results: The direct effect of loneliness on sleep quality was not statistically significant, but the indirect effect of depression on sleep quality was statistically significant. Depression mediated the relationship between loneliness and sleep quality. Depression can affect emotional health and reduce sleep quality. We should reduce the loneliness of patients, prevent the occurrence of depression and improve the quality of sleep. [ABSTRACT FROM AUTHOR]

Blockchain technology has attracted a lot of attention lately because it is seen as an all-purpose method for conducting online transactions between unidentified parties without the need for a centralized authority. Modern developers and businesspeople think it will disrupt or even change both the government and industry. In this setting, government-focused blockchains are becoming increasingly prevalent. Several recent studies highlighted use cases in the public sector for decentralized information infrastructures. Blockchain is expected to revolutionize or at least simplify many governmental functions. However, because blockchain use has yet to be widely adopted in government or industrial settings, the question arises: what are the technical hurdles impeding blockchain adoption? To that purpose, a systematic literature assessment of 29 academic articles investigating software engineering problems in blockchain technology for government applications has been done. The papers are initially inductively analyzed in order to illustrate and identify the issues frequently highlighted in academic literature. Furthermore, a theoretical framework is discussed by relying on models used in traditional software development, which is then followed by deductive analysis to map out the blockchain use cases and future trends connected to the difficulties. [ABSTRACT FROM AUTHOR]

Physics learning provides a context for future careers in fostering ability in high-end logic with the 21st learning goals. Applying computational thinking in schools is challenging and requires systemic transformation and teacher attention. This study aims to investigate the computational thinking of students in physics learning. This study used exploratory qualitative research. Data were gathered through observation, interviews, and portfolio documents. The data are analyzed through six stages: preparing and organizing, exploring, building descriptions, representing the findings, interpreting the results, and validating the accuracy. The result indicated four primary computational thinking skills: decomposition, abstraction, simulation, and evaluation. The computational thinking skills in physics learning can develop students’ understanding and implementation of physics concepts based on data, not just mathematical formulas. Computational thinking in physics learning gives students the opportunity and space to explore and develop their ideas and logical reasoning more deeply in problem-defining, solutions, and evaluation. Students use their logical reasoning to solve the problem precisely. This study is expected to be used as a basis and support for physics teachers to integrate computational thinking into their learning classroom. [ABSTRACT FROM AUTHOR]

The development of stable barium (Ba) isotope measurements provides a novel tool to investigate the geochemical cycling of Ba in the ocean and its sediments. In sediment pore waters, gradients of dissolved Ba concentrations result from various diagenetic processes. The distribution and fractionation of Ba isotopes in the pore waters are expected to further improve our understanding of these early diagenetic control mechanisms. Here, we present pore water profiles of dissolved stable Ba isotopic signatures (δ138Bapw) from shallow water sediments covering the entire Pearl River Estuary (PRE) in Southern China. We find pronounced depth‐dependent Ba isotope variations generally showing a shift from heavy to light δ138Bapw signatures from the sediment surface down to 15 cm depth. These gradients are well reproduced by a diffusion‐reaction model, which generates an apparent fractionation factor (138ε) of −0.60 ± 0.10‰ pointing to preferential removal of low‐mass Ba isotopes from the pore water during solution‐solid phase interactions. Consequently, the combined diagenetic processes induce the highest δ138Bapw values of +0.5 to +0.7‰ in the pore waters of the topmost sediment layer. Although the detrital fraction dominates the Ba content in the PRE surface sediments, the determined gradients of pore water Ba isotopes, together with concentration variations of Ba and other redox‐sensitive elements such as manganese (Mn), show that non‐detrital excess Ba carriers including Mn oxides and authigenic barite clearly affect the post‐depositional Ba dynamics. Stable Ba isotopes are thus a potentially powerful tracer of Ba geochemistry during early sediment diagenesis in estuarine depositional environments. Plain Language Summary: Dissolved barium (Ba) concentrations change with depth in sediment pore waters because of various chemical reactions involving the formation and dissolving of manganese (Mn) and barite (BaSO4) minerals. The development of stable Ba isotope measurements provides a novel tool to better understand these reactions in sediment pore waters. Here, we measured the dissolved stable Ba isotopic compositions in sediment pore waters near the bottom of the Pearl River Estuary, China. Pore water Ba isotopic signatures generally decrease from the sediment surface downward. The change of Ba concentrations and isotopic compositions measured in the field is well reproduced by a chemical model including diffusion and mineral formation/dissolving processes. This change in pore water Ba isotopes results from a combination of different processes including Ba sticking to sediment particles formed during the cycling of Mn minerals and the formation of BaSO4 minerals, which preferentially remove lighter Ba isotopes from the pore water into the solids. This is significant because it allows pore water Ba isotopes to be used to trace chemical reactions during Ba cycling in freshwater and marine sediments. Key Points: We present a data set of dissolved stable Ba isotopic compositions in surface sediment pore waters of a large river estuaryPore water Ba isotope values generally decrease with increasing sediment depth, reflecting post‐depositional Ba isotope fractionationA diffusion‐reaction model predicts the distribution and fractionation of stable Ba isotopes in the sediment pore waters well [ABSTRACT FROM AUTHOR]

The effect of the inhomogeneity of a scattering and absorbing medium of finite thickness on the evolution of spectrum lines which appear when it is illuminated by nonstationary energy sources is examined. Special attention is devoted to the role of scattering in the continuum spectrum. It is assumed that the inhomogeneity arises from the variation in the scattering coefficient with depth, which may be increasing or decreasing on approaching the illuminated boundary. Two types of nonstationarity of the external energy source are studied with a shape corresponding to δ(t), the Dirac function, and H(t), the unit step function of Heaviside. The question of using observed time changes in the profiles of spectrum lines for determining their optical characteristics, the frequency dependence of the external energy sources, and the physical properties of the illuminated medium itself, is studied. [ABSTRACT FROM AUTHOR]

In the Czech Republic, a new concept that proposes an Informatics curriculum for primary schools was prepared to meet the new requirements of the field. For the implementation to be smooth, a two-year transition period was planned from 2021 to 2023. Training seminars were the main tool to help teachers develop missing subject knowledge and didactic skills. After the first year of the transition period, the question was whether the seminars met the needs of teachers. Therefore, the main objective of the investigation was to collect feedback from them (N = 142) in five regions (of 14), consider changes within the first year (from autumn 2021 to autumn 2022), and propose recommendations for the rest of the period (by autumn 2023). The ex post facto method was used. Data were collected by questionnaires in five areas: (1) preference for an original or new concept for a curriculum, (2) and subject knowledge and didactic skills of teachers, (3) school equipment; (4) learning materials and teaching methods used, and (5) experience in online learning and teaching. The results show that in autumn 2022, the support for the new concept increased and the school equipment improved; however, subject knowledge and didactic skills were the weak points. Individualization through the tailoring of the seminars to the needs of teachers represents an efficient way to train them according to their level of knowledge, their preferred form of learning, and the learning content. [ABSTRACT FROM AUTHOR]

The Arctic is warming at almost four times the global rate. An estimated sixty percent of greenhouse‐gas‐induced Arctic warming has been offset by anthropogenic aerosols, but the contribution of aerosols to radiative forcing (RF) represents the largest uncertainty in estimating total RF, largely due to unknown preindustrial aerosol abundance. Here, sulfur isotope measurements in a Greenland ice core show that passive volcanic degassing contributes up to 66 ± 10% of preindustrial ice core sulfate in years without major eruptions. A state‐of‐the‐art model indicates passive volcanic sulfur emissions influencing the Arctic are underestimated by up to a factor of three, possibly because many volcanic inventories do not include hydrogen sulfide emissions. Higher preindustrial volcanic sulfur emissions reduce modeled anthropogenic Arctic aerosol cooling by up to a factor of two (+0.11 to +0.29 W m−2), suggesting that underestimating passive volcanic sulfur emissions has significant implications for anthropogenic‐induced Arctic climate change. Plain Language Summary: Sulfate aerosols are particles in the atmosphere that have a net cooling effect on the climate. One of the most uncertain aspects of climate modeling is the abundance of sulfate aerosols during the preindustrial era. Without knowing the amount of sulfate aerosols during the preindustrial, it is difficult to estimate how much anthropogenic sulfate aerosols have offset warming from anthropogenic greenhouse gases. In this study, we examine preindustrial sulfate aerosols in a Greenland ice core. We find that sulfate aerosols from passive (i.e., non‐eruptive) volcanic degassing contribute almost two thirds of preindustrial Arctic sulfate aerosols in years without major volcanic eruptions. We compare this result to a state‐of‐the‐art global model and find that most climate models use a volcanic emissions inventory that underestimates preindustrial passive volcanic sulfur emissions. That volcanic inventory only includes one type of sulfur emission (sulfur dioxide), but studies have shown that volcanoes emit hydrogen sulfide, which can also form sulfate aerosols. We show that higher emissions of volcanic sulfur during the preindustrial era decrease the estimated cooling effect of anthropogenic aerosols during the industrial era. Thus, the underestimate of preindustrial volcanic emissions in current climate models has significant implications for anthropogenic climate change in the Arctic. Key Points: Sulfur isotopes in a Greenland ice core show that passive volcanic degassing contributes 66% of preindustrial Arctic sulfateThe volcanic inventory used by most climate models underestimates passive degassing, possibly due to missing hydrogen sulfide emissionsElevated preindustrial passive volcanic degassing reduces the estimated cooling effect of anthropogenic sulfate in the Arctic [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Informática na Educação is the property of Revista Brasileira de Informatica na Educacao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Porosity generated during fluid–rock reaction can facilitate fluid transport and metasomatism in low permeability high-pressure metamorphic rocks. Evidence for reaction-induced porosity is found in an eclogite-facies clinopyroxene + apatite vein in an undeformed eclogitized Fe–Ti metagabbro from the Monviso Ophiolite (W. Alps) with a distinct garnet-rich selvage. Vein-forming fluids were sourced from adjacent metagabbros and reaction with the host rock removed Ca and P from the selvage and added Fe, REE, Pb and Cr. Textures at the selvage–host rock interface and in the host rock record local heterogeneity in reactivity and porosity during metasomatism linked to variable initial lawsonite abundance. These features reflect a hierarchy of pervasive-to-channelized porosity structures that facilitated widespread metasomatism of the host rock. Development of this metasomatic system in response to locally derived fluids suggests large-scale externally derived fluid transport is not required to drive extensive fluid–rock exchange. The production of porosity during metasomatic reactions could be important in facilitating further fluid–rock reaction and fluid transport in subducting slabs where permeability is low. [ABSTRACT FROM AUTHOR]

Copyright of TE & ET: Revista Iberoamericana de Tecnología en Educación y Educación en Tecnología is the property of School of Computer Science, La Pata University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Once started, existing hash tables cannot change their pre-defined hash functions, even if the incoming data cannot be evenly distributed to the hash table buckets. In this paper, we present DHash, a type of hash table for shared memory systems, that can change its hash function and rebuild the hash table on the fly, without noticeably degrading its service. The major technical novelty of DHash stems from an efficient distributing mechanism that can atomically distribute every node when rebuilding, without locking the corresponding hash table buckets. This not only enables non-blocking lookup, insert, and delete operations, but more importantly, makes DHash independent of the implementation of hash table buckets, such that DHash allows programmers to select the set algorithms that meet their requirements best from a variety of existing lock-free and wait-free set algorithms. Evaluations show that DHash can efficiently change its hash function on the fly. Moreover, when rebuilding, DHash consistently outperforms the state-of-the-art hash tables in terms of throughput and response time of concurrent operations, at different concurrency levels, and with different operation mixes and average load factors. [ABSTRACT FROM AUTHOR]

Contribution: This document presents a systematic bibliographic review that demonstrates the need to conduct research on how the user experience impacts the development of computational thinking. Background: In the field of computer science, computational thinking is defined as a method that enhances problem-solving skills, system design, and human behavior understanding. Over the last few decades, several tools have been proposed for the development of computational thinking skills; however, there is no area of study that evaluates the implications or the impact that these types of platforms have on users belonging to any knowledge area. Research Question: Do user interfaces influence the development of computational thinking skills? Methodology: To address this issue, a systematic review of the literature was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology for analyzing and evaluating scientific publications. Findings: The results show that despite the dearth of literature on the subject, the specific design of a user interface has a significant impact on the development of computational thinking. Bearing the above in mind, it is necessary to conduct research that delves more deeply into the effects caused by the technologies that are used to develop computational thinking, this being a line of research that is worthy of consideration. [ABSTRACT FROM AUTHOR]

Aim: Wildfire burned area, fire size, fire severity and the ecological and socio‐economic impacts of fire have been increasing rapidly in California in recent decades. We summarize the record‐breaking 2020 wildfire season in California statistically, evaluate the drivers of high‐severity burning in the 2020 fires and consider implications for fire and resource management. Location: California, USA. Time period: 2020, with consideration of long‐term trends in many variables. Major taxa studied: Humans, vegetation and wildlife. Methods: We statistically summarize the record‐breaking 2020 fire year in California and outline the salient ecological and socio‐economic impacts. Then we fit two statistical models to determine how a suite of weather‐ and fuel‐related variables influenced high‐severity burning in different vegetation types and in different fire events during the 2020 fire season. Results: In 2020, 1.74 million ha burned in California, 2.2 times more than the previous historical record but only average when compared with pre‐Euroamerican conditions. Economic losses exceeded $19 billion, and 33 people were killed directly by fire. Vegetation type and recent fire history had important effects on burning. Variability in high‐severity burning among vegetation types was driven principally by vapour pressure deficit and wind speed; variability among fire events was related principally to time since the last fire (a surrogate for fuel loading). Main conclusions: The 2020 fires were part of an accelerating decades‐long trend of increasing burned area, fire size, fire severity and socio‐ecological costs in California. In fire‐prone forests, the management emphasis on reducing burned area should be replaced by a focus on reducing the severity of burning and restoring key ecosystem functions after fire. There have been positive developments in California vis‐à‐vis collaborative action and increased pace and scale of fuel management and pre‐ and postfire restoration, but the warming climate and other factors are rapidly constraining our options. [ABSTRACT FROM AUTHOR]

Non-volatile memory (NVM), also known as persistent memory, is an emerging paradigm for memory that preserves its contents even after power loss. NVM is widely expected to become ubiquitous, and hardware architectures are already providing support for NVM programming. This has stimulated interest in the design of novel concepts ensuring correctness of concurrent programming abstractions in the face of persistency and in the development of associated verification approaches. Software transactional memory (STM) is a key programming abstraction that supports concurrent access to shared state. In a fashion similar to linearizability as the correctness condition for concurrent data structures, there is an established notion of correctness for STMs known as opacity. We have recently proposed durable opacity as the natural extension of opacity to a setting with non-volatile memory. Together with this novel correctness condition, we designed a verification technique based on refinement. In this paper, we extend this work in two directions. First, we develop a durably opaque version of NOrec (no ownership records), an existing STM algorithm proven to be opaque. Second, we modularise our existing verification approach by separating the proof of durability of memory accesses from the proof of opacity. For NOrec, this allows us to re-use an existing opacity proof and complement it with a proof of the durability of accesses to shared state. [ABSTRACT FROM AUTHOR]

Many people have preconceived notions about games and distrust the effects of game-based learning and show negative attitudes. In fact, there are limitations and disadvantages of game-based learning, and it is difficult to overcome them. More than half of the inconveniences or problems of teachers who want to try game-based learning revealed by the 2009 survey have not been solved yet. Due to the sudden spread of COVID-19, the Ministry of Education has issued a policy to convert classes at schools and academies into non-face-to-face. Non-face-to-face classes have the characteristics that instructors and learners will be spatially separated, spatially simultaneous, interactive, and teaching and learning behavior will be mediated by the screen. And these features are common to live streaming. Taking advantage of this, this study aims to approach improving the perception of game-based learning as an advantage of "watching games" beyond "playing games" by using live streaming for game-based learning. This study conducted game-based learning and game streaming learning for 210 third-year middle school students, compared the effects of game-based learning on learning interest, immersion, and satisfaction with the results of previous studies to verify the design and prove the combined effect of live streaming and game-based learning. In addition, in-depth interviews with instructors who conducted game-based learning confirmed that awareness of the introduction, value, and finance of game-based learning improved. [ABSTRACT FROM AUTHOR]

Soils and water resources of our ecosystems may contain Barium (Ba), a toxic metal naturally existent in the Earth’s crust and also can be derived from recycled wastes produced of several anthropogenic activities. As a result of this fact, the accumulation of Ba in agriculture soils would increase to reach the crops and eventually end up in the human food chain. The purpose of this work was to study tolerance and accumulation abilities in Limbarda crithmoides and Helianthus annuus treated with increasing concentrations of barium (from 0 to 500 µM) for 45 days. In order to evaluate the response of these species to Ba stress, the biomass production, the water status, and the accumulation of the secondary metabolites, macronutrients, total inorganic nitrogen (TIN), and Ba in shoots and roots, as well as chlorophyll levels, and metal tolerance index of the entire plant were assessed. Results showed an increase in plant biomass production and tolerance index in the two species with increasing Ba concentration. A significant increase in polyphenols and flavonoids levels was also shown with no negative effect on the macronutrients and TIN; however, the latter were found reduced in roots of L. crithmoides. Chlorophylls also were not affected. An average of 3000 µg·g −1 DW of Ba was accumulated in each organ of L. crithmoides while H. annuus accumulated up to 1350 µg·g −1 DW in the shoots. Our findings proved that L. crithmoides and H. annuus were susceptible to tolerate Ba-induced stress with high levels of Ba accumulation in the aboveground parts as well as in the roots during the 45 days of the experiments. [ABSTRACT FROM AUTHOR]

Digital interactions are taking on a more human-like appearance and behavior, but could or should they become our digital selves? [ABSTRACT FROM AUTHOR]

Aim: Wildfires increasingly create large high‐severity patches with interior areas far from less disturbed habitats. We evaluated how these trends impact bird communities by investigating the effect of internal distance from lower‐severity areas, high‐severity patch size, and years since fire on avian alpha and beta diversity. Location: Sierra Nevada, California, USA. Methods: Bird occurrence data were collected during 2009–2017 within high‐severity patches of 27 wildfires representing 1–30 years since disturbance. A two‐step multispecies occupancy method was used to account for imperfect detection of 94 species and estimate effects of patch characteristics on community richness and dissimilarity. Results: Community richness decreased with distance from patch edge and with patch size. Richness increased with years since fire, but this pattern was dependent on distance from edge with higher peak richness (23 species) near edges than interiors (18 species). Community dissimilarity was not associated with distance, indicating that large high‐severity patch interiors contain subsets of, rather than complements to, edge communities. Dissimilarity peaked later with increasing patch size. Guild richness of tree and primary cavity nesters was negatively associated with distance and patch size. Richness of ground and shrub nesters was insensitive to distance, while shrub nester richness increased somewhat with patch size. Due to declines among other species, ground and shrub nesters made up a greater percentage of the avian community within the interiors of large high‐severity patches. Main conclusions: As fire activity increases due to accumulating forest fuels and accelerating climate change, high‐severity patches and their resulting early‐seral habitats are becoming more extensive with less edge and more interior area. Such changes are likely to decrease avian diversity locally and shift community composition away from forest‐associated species. Management actions that promote the full range of fire effects but limit high‐severity patch size may best conserve bird diversity within fire‐adapted ecosystems. [ABSTRACT FROM AUTHOR]

Evidence about the relevance of the complement system, a highly conserved constituent of the innate immunity response that orchestrates the elimination of pathogens and the inflammatory processes, has been recently accumulated in many different rheumatologic conditions. In rheumatoid arthritis, complement, mainly the classical pathway, contributes to tissue damage especially in seropositive subjects, with complement activation occurring in the joint. Data about complement pathways in psoriatic arthritis are dated and poorly consistent; among patients with Sjögren syndrome, hypocomplementemia exerts a prognostic role, identifying patients at risk of extra-glandular manifestations. Hints about complement involvement in systemic sclerosis have been recently raised, following the evidence of complement deposition in affected skin and in renal samples from patients with scleroderma renal crisis. In vasculitides, complement plays a dual role: on one hand, stimulation of neutrophils with anti-neutrophil cytoplasmic antibodies (ANCA) results in the activation of the alternative pathway, on the other, C5a induces translocation of ANCA antigens, favouring the detrimental role of antibodies. Complement deposition in the kidneys identifies patients with more aggressive renal disease; patients with active disease display low serum levels of C3 and C4. Even though in dermatomyositis sC5b-9 deposits are invariably present in affected muscles, data on C3 and C4 fluctuation during disease course are scarce. C3 and C1q serum levels have been explored as potential markers of disease activity in Takayasu arteritis, whereas data in Behçet disease are limited to in vitro observations. Pregnancies in women with rheumatologic conditions are still burdened by a higher rate of pregnancy complications, thus the early identification of women at risk would be invaluable. A fine-tuning of complement activation is required from a physiological progression of pregnancy, from pre-implantation stages, through placentation to labour. Complement deregulation has been implicated in several pregnancy complications, such as recurrent abortion, eclampsia and premature birth; low complement levels have been shown to reliably identify women at risk of complications. Given its physiologic role in orchestrating pregnancy progression and its involvement as pathogenic effector in several rheumatologic conditions, complement system is an attractive candidate biomarker to stratify the obstetric risk among women with rheumatologic conditions. [ABSTRACT FROM AUTHOR]

The unified modeling language (UML) is used for the specification, visualization, and documentation of object-oriented software systems. Mobile UML (M-UML) is an extension of UML that considers mobility aspects, and a mobile statechart is an extension of the standard UML diagram that deals with the requirements for modeling, specifying, and visualizing mobile agent-based systems. However, mobile statecharts inherit UML's lack of formal notation for analysis and verification purposes. The rewriting logic language Maude is a formal method that deals with mobile computations. In this paper, we propose a formalization of M-UML statechart diagrams using Maude to provide formal semantics for such diagrams. The generated Maude specifications are then used to analyze and check the systems using Maude analytical tools. This approach is illustrated through an example. [ABSTRACT FROM AUTHOR]

This article presents a novel implementation of a snapshot object for n processes, with O(log² b log n) step complexity for update operations and O(log b) step complexity for scan operations, where b is the number of updates. The algorithm uses only reads and writes. For polynomially many updates, this is an exponential improvement on previous snapshot algorithms, which have linear step complexity. It overcomes the existing Ω(n) lower bound on step complexity by having the step complexity depend on the number of updates. The key to this implementation is the construction of a new object consisting of a pair of max registers that supports a scan operation. [ABSTRACT FROM AUTHOR]

The adoption of big data analysis in the legal domain is a recent but growing trend that highlights ethical concerns not just with big data analysis, as such, but also with its deployment in the legal domain. This article systematically analyses five big data use cases from the legal domain utilising a pluralistic and pragmatic mode of ethical reasoning. In each case we analyse what happens with data from its creation to its eventual archival or deletion, for which we utilise the concept of 'data life cycle'. Despite the exploratory nature of this article and some limitations of our approach, the systematic summary we deliver depicts the five cases in detail, reinforces the idea that ethically significant issues exist across the entire big data life cycle, and facilitates understanding of how various ethical considerations interact with one another throughout the big data life cycle. Furthermore, owing to its pragmatic and pluralist nature, the approach is potentially useful for practitioners aiming to interrogate big data use cases. [ABSTRACT FROM AUTHOR]

The male of a new species Arisemus venustus sp. n. from Nicaragua, the Cerro Musun Natural Reserve, is described. Arisemus atrasetus (Rapp, 1945) and Platyplastinx tango Quate et Brown, 2004 (Diptera: Psychodidae: Psychodinae) from Nicaragua are redescribed and illustrated based on male morphological characters. [ABSTRACT FROM AUTHOR]

Objective: Insulin sensitivity is lower in African American (AA) versus Caucasian American (CA). We tested the hypothesis that lower insulin sensitivity in AA could be explained by mitochondrial respiratory rates, coupling efficiency, myofiber composition, or H2O2 emission. A secondary aim was to determine whether sex affected the results. Methods: AA and CA men and women, 19–45 years, BMI 17–43 kg m2, were assessed for insulin sensitivity (SIClamp) using a euglycemic clamp at 120 mU/m2/min, muscle mitochondrial function using high‐resolution respirometry, H2O2 emission using amplex red, and % myofiber composition. Results: SIClamp was greater in CA (p < 0.01) and women (p < 0.01). Proportion of type I myofibers was lower in AA (p < 0.01). Mitochondrial respiratory rates, coupling efficiency, and H2O2 production did not differ with race. Mitochondrial function was positively associated with insulin sensitivity in women but not men. Statistical adjustment for mitochondrial function, H2O2 production, or fiber composition did not eliminate the race difference in SIClamp. Conclusion: Neither mitochondrial respiratory rates, coupling efficiency, myofiber composition, nor mitochondrial reactive oxygen species production explained lower SIClamp in AA compared to CA. The source of lower insulin sensitivity in AA may be due to other aspects of skeletal muscle that have yet to be identified. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Contribution: A technical course in a multidisciplinary university program has to provide high-level skills, with limited lecturing hours and student background. This article investigates the principles for its design and reports about a study case. Background: The overall course organization needs to address specific learning targets and teaching techniques, different from those used in traditional courses on the topic. Research Question: A stepwise strategy assists a principled design that allows dynamic, long-term improvements. Methodology: The evaluation of its applicability requires a years-long record of historical data. The article studies the evolution of a course over six years using simple monitoring techniques: surveys and rubric-based examinations. Findings: Monitoring emerges as an essential feature for course evolution: a focused examination provides the best results, while institutional, wide-spectrum surveys appear to be of little help. [ABSTRACT FROM AUTHOR]

Copyright of TE & ET: Revista Iberoamericana de Tecnología en Educación y Educación en Tecnología is the property of School of Computer Science, La Pata University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Protecting data-in-use from privileged attackers is challenging. New CPU extensions (notably: Intel SGX) and cryptographic techniques (specifically: Homomorphic Encryption) can guarantee privacy even in untrusted third-party systems. HE allows sensitive processing on ciphered data. However, it is affected by i) a dramatic ciphertext expansion making HE unusable when bandwidth is narrow, ii) unverifiable conditional variables requiring off-premises support. Intel SGX allows sensitive processing in a secure enclave. Unfortunately, it is i) strictly bonded to the hosting server making SGX unusable when the live migration of cloud VMs/Containers is desirable, ii) limited in terms of usable memory, which is in contrast with resource-consuming data processing. In this article, we propose the VIrtual Secure Enclave (VISE), an approach that effectively combines the two aforementioned techniques, to overcome their limitations and ultimately make them usable in a typical cloud setup. VISE moves the execution of sensitive HE primitives (e.g., encryption) to the cloud in a remotely attested SGX enclave, and then performs sensitive processing on HE data–outside the enclave–leveraging all the memory resources available. We demonstrate that VISE meets the challenging security and performance requirements of a substantial application in the Industrial Control Systems domain. Our experiments prove the practicability of the proposed solution. [ABSTRACT FROM AUTHOR]