Generation of trees of a graph with the use of decomposition

The method of tree generation of a graph decomposed into any number of parts is described in this paper. The decomposition of a graph is defined. The formula for the generation of trees of a decomposed graph is given in Theorem I. The necessary and sufficient conditions which a graph decomposition must satisfy to avoid duplications in the generated set of trees are discussed and results are summarized in Theorems II and III. A criterion for existence of such a decomposition is formulated in Theorem IV and also an appropriate algorithm for the graph decomposition is suggested.     

Children's query types and reformulations in Google search

We investigated the searching behaviors of twenty-four children in grades 6, 7, and 8 (ages 11–13) in finding information on three types of search tasks in Google. Children conducted 72 search sessions and issued 150 queries. Children's phrase- and question-like queries combined were much more prevalent than keyword queries (70% vs. 30%, respectively). Fifty two percent of the queries were reformulations (33 sessions). We classified children's query reformulation types into five classes based on the taxonomy by Liu et al. (2010). We found that most query reformulations were by Substitution and Specialization, and that children hardly repeated queries. We categorized children's queries by task facets and examined the way they expressed these facets in their query formulations and reformulations. Oldest children tended to target the general topic of search tasks in their queries most frequently, whereas younger children expressed one of the two facets more often. We assessed children's achieved task outcomes using the search task outcomes measure we developed. Children were mostly more successful on the fact-finding and fully self-generated task and partially successful on the research-oriented task. Query type, reformulation type, achieved task outcomes, and expressing task facets varied by task type and grade level. There was no significant effect of query length in words or of the number of queries issued on search task outcomes. The study findings have implications for human intervention, digital literacy, search task literacy, as well as for system intervention to support children's query formulation and reformulation during interaction with Google.     

Insulin sensitivity and β-cell function estimated by HOMA2 model in sprint-trained athletes aged 20−90 years vs endurance runners and untrained participants

Abstract

There are no studies available that portray insulin sensitivity and β-cell function in ageing sprint-trained athletes. We compared male young and master sprint-trained athletes to endurance-trained and untrained individuals. We hypothesised that ageing sprint-trained athletes would preserve insulin sensitivity and β-cell function at a level similar to that of endurance-trained peers and better than in untrained individuals. We showed the associations between age and parameters derived from the updated Homeostasis Model Assessment (HOMA2 model) in 52 sprint-trained track and field athletes (aged 20?90 years), 85 endurance runners (20?80 years) and 55 untrained individuals (20?70 years). Fasting glucose, fasting insulin, insulin sensitivity and β-cell function were not associated with age in sprint-trained athletes. These variables remained relatively stable across a wide range of age and comparable to those observed in endurance-trained athletes. In contrast, the untrained group showed considerable age-related increase in fasting insulin and β-cell activity and a strong decrease in insulin sensitivity compared to both athletic groups. HOMA2 parameters were significantly related to maximal oxygen in the combined group of participants. In summary, chronic training based on a “sprint model” of physical activity, that contains mixed exercise, seems to be effective in maintaining normal insulin sensitivity with ageing.     

Program of the Department of Cultural Heritage of the Ministry of Culture and National Heritage of the Republic of Poland

The article discusses the program “Registration of the Polish Collections Abroad,” conducted by the Department of Cultural Heritage of the Ministry of Culture and National Heritage of the Republic of Poland. Its goal is to create a register of the significant Polish collections outside Poland.     

不同外加碳源和电子受体对生物营养盐去除工艺中反硝化和除磷过程的影响（英文）

目的:考察两种不同性质的外加碳源(乙酸钠和乙醇)在三种不同的电子受体(溶解氧、硝酸盐和亚硝酸盐)条件下对聚磷菌和异养菌的影响机制。创新点:系统研究了乙酸钠和乙醇这两种外加碳源在溶解氧、硝酸盐和亚硝酸盐三种不同电子受体条件下的释磷、吸磷及反硝化过程。方法:利用具有脱氮除磷功能的活性污泥,开展了一系列一阶段批次试验和两阶段批次试验。一阶段批次试验包括厌氧释磷试验、好氧吸磷试验、硝酸盐及亚硝酸盐利用速率(NUR)试验。两阶段批次试验包括厌氧/好氧试验、厌氧/缺氧试验。通过改变外加碳源的投加条件,如投加类型(乙酸钠和乙醇)、投加环境(厌氧、好氧和缺氧)、缺氧区电子受体(硝酸盐及亚硝酸盐),考察两种不同类型的外加碳源在不同电子受体条件下对除磷和脱氮过程的影响。结论:(1)当乙酸钠作为外加碳源时,在溶解氧、硝酸盐和亚硝酸盐三种不同电子受体条件下均发生了释磷,释磷速率分别为1.70、7.80和3.50 mg P/(g MLVSS·h)。当乙醇作为外加碳源时,三种电子受体条件下均未发现有释磷。(2)无论乙酸钠还是乙醇作为外加碳源,未经驯化的活性污泥聚磷菌均不能利用亚硝酸盐作为电子受体,25 mg NO2-N/L的亚硝酸盐完全抑制了吸磷过程的进行。(3)以硝酸盐作为电子受体时,乙酸钠和乙醇的NUR值分别为2.3和1.5 mg N/(g MLVSS·h),比亚硝酸盐作电子受体的NUR值(分别为1.2和1.0 mg N/(g MLVSS·h))分别高出92%和50%。乙酸钠作为碳源的NUR值总是比相同条件下以乙醇作为碳源的NUR值高。     

The Ethos of Science in Contemporary Poland

Modern science is moving away from Michael Polanyi’s vision of ‘the Republic of Science’ and gradually becoming subordinate to political and economic social institutions. This process is accompanied by changes in the normative structure of science. Poland provides an interesting case for empirical study of the scientific ethos mostly because in a relatively short time it experienced a significant reform of the science system, especially in terms of evaluating and financing scientific work. In this paper we examine whether different sets of values and norms are embedded into the normative structure of science in contemporary Poland. The results of a representative survey conducted among 801 researchers were examined with the use of confirmatory factor analysis and fuzzy clustering. The statistical analysis revealed a great complexity in the normative structure of science that goes beyond the expectations formulated on the basis of the theories reviewed. We identified three distinctive groups of researchers, guided by different sets of values and norms in their professional conduct (academic science, post-academic science and the industrial science) and a cluster of researchers with an unidentified system of principles. We argue that the complexity of the normative structure of science should be taken into account in the decision-making regarding any future reforms of the science system.

     

Are School-Provided Skills Useful at Work? Results of the Wiles Test

Research in Higher Education - We test for the signaling hypothesis versus the human capital theory using the Wiles test in a country which has experienced a dramatic increase in the supply of...     

Inferring user knowledge level from eye movement patterns

The acquisition of information and the search interaction process is influenced strongly by a person’s use of their knowledge of the domain and the task. In this paper we show that a user’s level of domain knowledge can be inferred from their interactive search behaviors without considering the content of queries or documents. A technique is presented to model a user’s information acquisition process during search using only measurements of eye movement patterns. In a user study (n = 40) of search in the domain of genomics, a representation of the participant’s domain knowledge was constructed using self-ratings of knowledge of genomics-related terms (n = 409). Cognitive effort features associated with reading eye movement patterns were calculated for each reading instance during the search tasks. The results show correlations between the cognitive effort due to reading and an individual’s level of domain knowledge. We construct exploratory regression models that suggest it is possible to build models that can make predictions of the user’s level of knowledge based on real-time measurements of eye movement patterns during a task session.     

Participation,progression and value added: business and economics for 14–19-year-olds in England

This article attempts to map the business and economics curriculum and explain some of the reasons for it being as it is; and to examine the number of students choosing to study the subjects and the ‘perceived relative value’ of studying economics and business studies. In 1988 a National Curriculum was introduced for all 5–16-year-olds in state schools in England but curiously neither business studies nor economics were mandatory subjects. In England, government education policy has influenced the development of the business and economics school curriculum in four main ways: first, in defining a core curriculum; second, in changes in school type; third, in the treatment of the academic/vocational divide; and, finally, in the development of a qualifications framework. With a new government elected, changes in education policy will therefore have an impact on the study of these subjects. We argue that while business and economics are very popular options for study by 14–19-year-olds, this area of the English curriculum needs further strengthening, and that all students should have the opportunity to study business and economics in some form to develop their own economic wellbeing and to better understand the world in which they live.