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关键词： ageing   alcohol   CHAID   older adults   quality of life  

摘要： This investigation derives its impetus from public health concerns around detecting, mitigating, and preventing the deleterious effects that alcohol use can cause particularly in advanced age. We aim to complement gerontological research by exploring the interactive effects of quality of life and related factors on alcohol use outcomes assessed by the Drinking Problem Index. The study is based on cross-sectional data collected from questionnaires mailed to a randomly drawn sample of 6,000 Norwegian adults aged 62 and older (participation rate: 32%). According to the Chi-square Automatic Interaction Detection (CHAID) analysis, constellations of interactive factors emerged differently for women and men, and, between non-problem and problem drinkers. For women, drinking outcomes were related to intra-psychic functioning, and for men, to physical health and social situation. An ongoing quality-of-life assessment may be very important in the comprehensive assistance provided to those older people who are vulnerable to undergoing alcohol-related harms.

关键词： cultural politics   Blackness   race   racism   social movements  

摘要： This article examines the debates on Blackness, race, and black culture in the First Congress of Black Culture of the Americas, held in Cali, Colombia, in 1977. This analysis shows the reception and contributions of the discourses of Blackness in Latin America. The discussions and debates held during the First Congress reveal an ideological dispute that led to its reconceptualization beyond the homogeneous anthropological vision that weighs on Blackness. To demonstrate this, the following questions are addressed. What was the relationship of the First Congress with the Afro-diasporic movements? How did the discussions at the First Congress bring new meanings to the concepts of race, black culture, and Blackness? Based on these discussions, how can we understand the relationship between Black culture and politics in Latin America? This article shows how attendants politicized black culture, resignified the idea of negritud and defined Latin America as racist.

关键词： Academic change   Buy-in   Computer science   Engineering   Shared vision   Stakeholders  

摘要： Shared vision is an important process for change projects, serving to amplify success, increase participation, and erode the divide between project leaders and constituents. Yet there are few empirical examinations of the process of building shared vision within academic departments. Using focus groups and participant observation, this study examines shared vision development within 13 large-scale change projects in engineering and computer science higher education. We find that teams of faculty, staff, administrators, and students built shared vision with stakeholders through co-orientation, formational communication, and recognition of stakeholder autonomy. Our results delineate practices for developing shared vision for academic change projects and demonstrate the benefits of inclusive stakeholder empowerment.

关键词： Construction workers   Activity classification   Productivity analysis   Wearable accelerometers   Supervised machine learning  

摘要： Automated Construction worker activity classification has the potential to not only benefit the worker performance in terms of productivity and safety, but also the overall project management and control. The activity-level knowledge and indicators that can be extracted from this process may support project decision making, aiding in project schedule adjustment, resource management, construction site control, among others. Previous works on this topic focused on the collection and classification of worker acceleration data using wearable accelerometers and supervised machine learning algorithms, respectively. However, most of these studies tend to consider small sets of activities performed in an instructed manner, which can lead to higher accuracy results than those expected in a real construction scenario. To this end, this paper builds on the results of these past studies, committing to expand this discussion by covering a larger set of complex Construction activities than the current state-of-the-art, while avoiding the need to instruct test subjects on how and when to perform each activity. As such, a Machine Learning methodology was developed to train and evaluate 13 classifiers using artificial features extracted from raw accelerometer data segments. An experimental study was carried out under the form of a realistic activity-circuit to recognise ten different activities: gearing up;hammering;masonry;painting;roughcasting;sawing;screwing;sitting;standing still;and walking;with most activities being a cluster of simpler tasks (i.e. masonry includes fetching, transporting, and laying bricks). Activities were initially separated and tested in three different activity groups, before assessing all activities together. It was found that a segment length of 6 s, with a 75% overlap, enhanced the classifier performance. Feature selection was carried out to speed the algorithm running time. A nested cross-validation approach was performed for hyperparameter tuning and

关键词： Computer science education   post-secondary education   secondary education   advanced placement Introduction  

摘要： Success in an introductory college computer science (CS) course encourages students to major and pursue careers in computer science and many other STEM fields, whereas weak performance is often a powerful deterrent. This article examines the role of high school course taking (AP, regular, or none) in mathematics and in CS as predictors of later success in college introductory computer science courses, measured by students' final grades. Using a sample of 9,418 students from a stratified random sample of 118 U.S. colleges and universities, we found that the observed advantage of taking AP calculus over taking AP CS, seen in an uncontrolled model, was largely confounded by students' background characteristics. After applying multinomial propensity score weighting, we estimated that the effects of taking AP calculus and AP CS on college CS grades were similar. Interestingly, enrollment in both AP calculus and AP CS did not have any additional positive effect, suggesting that both AP calculus and AP CS strengthened similar skills that are important for long-term CS achievement. Taking regular CS did not have a significant effect;taking regular calculus had a positive effect, about half the size of taking AP calculus or AP CS. Thus, the study showed that simply exposing students to any kind of CS course before college does not appear to be sufficient for improving college CS performance;and that advanced CS and advanced calculus in high school may substitute for each other in the preparation of college CS.

关键词： Antarctica   cryptoendolithic communities   metabarcoding   black fungi   extremophiles  

摘要： In the harshest environmental conditions of the Antarctic desert, normally incompatible with active life, microbes are adapted to exploit the cryptoendolithic habitat (i.e., pore spaces of rocks) and represent the predominant life-forms. In the rocky niche, microbes take advantage of the thermal buffering, physical stability, protection against UV radiation, excessive solar radiation, and water retention-of paramount importance in one of the driest environments on Earth. In this work, high-throughput sequencing and culture-dependent approaches have been combined, for the first time, to untangle the diversity and distribution of black fungi in the Antarctic cryptoendolithic microbial communities, hosting some of the most extreme-tolerant microorganisms. Rock samples were collected in a vast area, along an altitudinal gradient and opposite sun exposure-known to influence microbial diversity-with the aim to compare and integrate results gained with the two approaches. Among black fungi, Friedmanniomyces endolithicus was confirmed as the most abundant taxon. Despite the much stronger power of the high-throughput sequencing, several species were not retrieved with DNA sequencing and were detectable by cultivation only. We conclude that both culture-dependent and -independent analyses are needed for a complete overview of black fungi diversity. The reason why some species remain undetectable with molecular methods are speculated upon. The effect of environmental parameters such as sun exposure on relative abundance was clearer if based on the wider biodiversity detected with the molecular approach.

关键词： Stability analysis   Security   Labeling   Business   Tools   IP networks   Computer science   Network measurement   host profiling   netflow   clustering   temporal patterns  

摘要： An analysis of a host behavior is an essential key for modern network management and security. A robust behavior profile enables the network managers to detect anomalies with high accuracy, predict the host behavior, or group host to clusters for better management. Hence, host profiling methods attract the interest of many researchers, and novel methods for host profiling are being introduced. However, these methods are frequently developed on preprocessed and small datasets. Therefore, they do not reflect the real-world artifacts of the host profiling, such as missing observations, temporal patterns, or variability in the profile characteristics in time. To provide the needed insight into the artifacts of host profiling in real-world settings, we present a study of the host behavior in a network conducted on a one-year-long real-world network dataset. In the study, we inspect the availability of the data for host profiling, identify the temporal patterns in host behavior, introduce a method for stable labeling of the hosts, and assess the variability of the host characteristics in the course of the year using the coefficient of variance. Moreover, we make the one-year dataset containing nine characteristics used for host behavior analysis available for public use and further research, including selected use cases representing host profiling caveats. We also share the record of analysis presented in the paper.

关键词： Blockchain   Medical services   Consensus algorithm   Internet of Things   Computer architecture   Organizations   Computer science   Blockchain   e-health   healthcare   Internet of Things (IoT)   IoT data  

摘要： Internet of Things (IoT) and blockchain technologies are being heavily exploited and used in may domains, especially for e-healthcare. In healthcare, IoT devices have the ability to provide real-time sensory data from patients to be processed and analyzed. Collected IoT data are subjected to centralized computation, processing, and storage. Such centralization can be problematic, as it can be a single point of failure, mistrust, data manipulation and tampering, and privacy evasion. Blockchain can solve such serious problems by providing decentralized computation and storage for IoT data. Therefore, the integration IoT and blockchain technologies can become a reasonable choice for the design of a decentralized IoT-based e-healthcare systems. In this article, first, we give a brief background on blockchain. Second, popular consensus algorithms used in blockchain are discussed in the context of e-health. Third, blockchain platforms are reviewed for their appropriateness in IoT-based e-healthcare. Finally, few use cases are methodologically given to show how key features of the IoT and blockchain can be leveraged to support healthcare services and ecosystems. We also propose a data-flow architecture that combines the IoT with blockchain, called IoBHealth, that can be used for storing, accessing, and managing of e-healthcare data.