Knowledge bases in medicine: a review

Efforts to represent knowledge effectively have been central to progress in various aspects of medical informatics. These efforts range from relatively simple "electronic textbooks" to fairly sophisticated knowledge-based systems, which function as well as, or even better than, human experts faced with similar problems. Knowledge bases have been developed in many fields, but the relatively limited domains and structured language of medicine, as well as the importance of information in the provision of good medical care, have made research in medical knowledge representation an area of intense activity. This paper reviews representative knowledge bases and knowledge-based systems in medicine: electronic textbooks such as PDQ and the Hepatitis Knowledge Base (HKB), rule-based systems such as MYCIN, causal models (e.g., CASNET), and hypothesis- or frame-based systems, exemplified by PIP and INTERNIST-1. The paper describes the relationships among divergent approaches and provides a sense of current and future trends. It examines problems in knowledge-based systems, particularly in knowledge representation and acquisition, and the responses to these challenges. The latter include the use of domain-independent software shells for constructing knowledge bases, the adaptation and use of previously existing knowledge bases, and multiple uses of the same knowledge base for different purposes.     

Inter-participant variability in daily physical activity and sedentary time among male youth sport footballers: independent associations with indicators of adiposity and cardiorespiratory fitness

Participation in youth sport is assumed to promote and contribute towards more physically active lifestyles among children and adolescents. The aim of this study was to examine inter-participant variability in objectively measured habitual physical activity (PA) behaviours and sedentary time among youth sport participants and their implications for health. One-hundred-and-eighteen male youth sport footballers (Mean ± s = 11.72 ± 1.60) wore a GT3X accelerometer for 7 days. Average daily PA [min · day^?1, in light (LPA), moderate (MPA), vigorous (VPA) and combined moderate-to-vigorous (MVPA)] and sedentary time were calculated. Participants’ body mass index adjusted for age and sex (BMI–standard deviation score), per cent body fat (BF%), waist circumference and cardiorespiratory fitness were assessed. Results revealed that variability in daily PA behaviours and sedentary time (min · day^?1) was associated with BMI–standard deviation score [VPA (?), MVPA (?)], BF% [sedentary time (+), VPA (?), MVPA (?)], waist circumference [sedentary time (+), LPA (?)] and cardiorespiratory fitness [sedentary time (?), MPA (+), VPA (+), MVPA (+)]. Whilst sedentary time and MVPA were not related to health outcomes independent of one another, associations with markers of adiposity and cardiorespiratory fitness were stronger for sedentary time. Sedentary time was also significantly positively related to waist circumference independent of VPA. Results demonstrate inter-participant variability in habitual PA and sedentary time among youth sport participants which holds implications for their health. Thus, promoting PA and, in particular, reducing sedentary time may contribute towards the prevention of adverse health consequences associated with a physically inactive lifestyle for children and adolescents active in the youth sport context.     

On the Complexity of the Reduction of Multidimensional Data Models

In this paper, decomposition methods for multidimensional data hypercubes of OLAP systems are investigated. Criteria for reducing the computational complexity of the decomposition methods are presented and comparisons are made with the traditional solutions of multidimensional data analysis problems. Examples illustrating the application of these criteria to investigating the dynamics of computational complexity changes for specific types of reduction problems are considered.     

The nature of the modern information society

In this paper, a survey and critique are presented of the existing concepts of an information society. The concept of a “modern information society” is introduced. The main components of the information society concept are analyzed, i.e., information, information technologies and the IT workforce (specialists). Changes are considered in the main spheres of human activities. A broad definition of the modern information society is formulated.     

Impact of school-type and sex of the teacher on female students' attitudes toward mathematics in Nigerian secondary schools

The purpose of the study was to identify female students' attitudes toward mathematics when studying under four conditions and to assess the impact of school-type and sex of teacher on students' attitudes toward mathematics. An instrument to measure attitude toward mathematics was administered on a stratified random sample of 240 female students drawn from 5 co-educational and 6 all-girls' secondary schools in Plateau State, Nigeria. The findings suggest that the best environment under which females can learn mathematics is in all-girls' secondary schools where mathematics is taught by female teachers.     

Language and reading impairments are associated with increased prevalence of non-right-handedness

Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (N_cases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.     

Educational impact on the relationship of environmental knowledge and attitudes

This study examines the relationships between the environmental attitudes and environmental knowledge of schoolchildren within the framework of an environmental intervention. We employed questions from the 2-MEV model to monitor students’ environmental attitudes in terms of the model factors Preservation and Utilisation while concurrently monitoring three environmental knowledge dimensions (system, action-related and effectiveness knowledge) at three different test times during the course of a four-day field centre programme for fourth-graders (N = 133, M_age = 9.8 years). Probably due to measurement constraints (e.g. a ceiling effect, social desirability), we found no correlation between environmental knowledge and the attitude Preservation at all test times. The attitude Utilisation correlated negatively with all environmental knowledge dimensions, indicating that students who score higher on Utilisation are more likely, for example, to have and gain more system knowledge through programme participation than the other students or vice versa, as a causal relationship cannot be derived from our analyses: system knowledge may also influence Utilisation. In other words, children who refrain from (ab)using nature also seem to put more effort into improving their environmental knowledge and/or children who engage in learning about the environment will become less exploitative towards the environment.     

Trends in Public Library Design from the 19th to the 21st Centuries

In the early 19th century, public libraries in America tended toward grand appearances befitting seriousness of purpose. Library design changed gradually throughout the 20th and 21st centuries, and more dramatically with automation and new technology. True to its roots, the public library continues to maintain areas for quiet, individual study. But, in addition, today’s library has become a cultural center in the community, offering art galleries, auditoriums, meeting rooms, spaces for collaborative work, digital information and instruction, and even cafés. Change is inevitable, as innovations in library design and patron use illustrate. Yet, from the earliest libraries to modern times, one overarching constant defines their purpose: libraries inspire.     

丹巴县高中阶段教育发展调研报告

丹巴县高中阶段教育现状可归纳为：经济地理限制,发展基础薄弱;校园占地面积狭小,无扩展空间;资金投入少,资源配置不足;优质教师外流,优质生源外流;高中阶段普及率低,高考上线率低;学校缺乏竞争力,师生向心力不强。