Towards mathematical literacy in the 21st century : perspectives from Indonesia

The notion of mathematical literacy advocated by PISA (OECD, 2006) offers a broader conception for assessing mathematical competences and processes with the main focus on the relevant use of mathematics in life. This notion of mathematical literacy is closely connected to the notion of mathematical modelling whereby mathematics is put to solving real world problems. Indonesia has participated as a partner country in PISA since 2000. The PISA trends in mathematics from 2003 to 2009 revealed unsatisfactory mathematical literacy among 15-year-old students from Indonesia who lagged behind the average of OCED countries. In this paper, exemplary cases will be discussed to examine and promote mathematical literacy at teacher education level. Lesson ideas and instruments were adapted from PISA 2006 released items. The potential of such tasks will be discussed based on case studies of implementing these instruments with samples of pre-service teachers in Yogyakarta. 

Structure and biodegradation mechanism of milled Bombyx mori silk particles

The aim of this study was to understand the structure and biodegradation relationships of silk particles intended for targeted biomedical applications. Such a study is also useful in understanding structural remodelling of silk debris that may be generated from silk-based implants. Ultrafine silk particles were prepared using a combination of efficient wet-milling and spray-drying processes with no addition of chemicals other than those used in degumming. Milling reduced the intermolecular stacking forces within the β-sheet crystallites without changing the intramolecular binding energy. Because of the rough morphology and the ultrafine size of the particles, degradation of silk particles by protease XIV was increased by about 3-fold compared to silk fibers. Upon biodegradation, the thermal degradation temperature of silk increased, which was attributed to the formation of tight aggregates by the hydrolyzed residual macromolecules. A model of the biodegradation mechanism of silk particles was developed based on the experimental data. The model explains the process of disintegration of β-sheets, supported by quantitative secondary structural analysis and microscopic images. © 2012 American Chemical Society.

Lipid merging, protrusion and vesicle release triggered by shrinking/swelling of poly(N-isopropylacrylamide) microgel particles

Cell membrane changes its morphology during many physiological processes with the assistance of a solid support, such as the cytoskeleton, under an environmental stimulus. Here, a novel type of stimuli-responsive lipogel was fabricated, mimicking the changes of cell membrane. The lipogel was prepared from poly(N-isopropylacrylamide) (pNIPAM) microgel particle and phospholipid by a solvent-exchange method. The temperature dependent volume phase transition of pNIPAM triggers reversible transformation of the lipogel between a lipid vesicle-coated sun-like structure and a contracted hybrid sphere, through lipid merging and protrusion processes, respectively. By contrast, the salt induced pNIPAM phase transition leads to an irreversible vesicle release behaviour. The lipogel creates a unique platform for studying cell membrane behaviour and provides promising candidates in drug delivery and controlled release applications. © 2014 Elsevier B.V. All rights reserved.

Zebrafish as a model for leukemia and other hematopoietic disorders

Zebrafish is an established model for the study of vertebrate development, and is especially amenable for investigating hematopoiesis, where there is strong conservation of key lineages, genes, and developmental processes with humans. Over recent years, zebrafish has been increasingly utilized as a model for a range of human hematopoietic diseases, including malignancies. This review provides an overview of zebrafish hematopoiesis and describes its application as a model of leukemia and other hematopoietic disorders.

K-Center: an approach on the multi-source identification of information diffusion

The global diffusion of epidemics, computer viruses, and rumors causes great damage to our society. It is critical to identify the diffusion sources and timely quarantine them. However, most methods proposed so far are unsuitable for diffusion with multiple sources because of the high computational cost and the complex spatiotemporal diffusion processes. In this paper, based on the knowledge of infected nodes and their connections, we propose a novel method to identify multiple diffusion sources, which can address three main issues in this area: 1) how many sources are there? 2) where did the diffusion emerge? and 3) when did the diffusion break out? We first derive an optimization formulation for multi-source identification problem. This is based on altering the original network into a new network concerning two key elements: 1) propagation probability and 2) the number of hops between nodes. Experiments demonstrate that the altered network can accurately reflect the complex diffusion processes with multiple sources. Second, we derive a fast method to optimize the formulation. It has been proved that the proposed method is convergent and the computational complexity is O(mn log α) , where α = α (m,n) is the slowly growing inverse-Ackermann function, n is the number of infected nodes, and m is the number of edges connecting them. Finally, we introduce an efficient algorithm to estimate the spreading time and the number of diffusion sources. To evaluate the proposed method, we compare the proposed method with many competing methods in various real-world network topologies. Our method shows significant advantages in the estimation of multiple sources and the prediction of spreading time.

Motivational processes associated with unhealthy body change attitudes and behaviours

Objective
The relationship between approach–avoidance motivational processes and unhealthy body change attitudes and behaviours was investigated.
Method
Self-reported sensitivity to rewards (SR) and sensitivity to punishments (SP) were measured for a convenience sample of 130 women, aged 18 to 40 years, along with measures of disordered eating symptomatology and exercise dependence.
Results
Together, SR and SP significantly predicted variance in drive for thinness (21%), bulimia (17%), and obligatory exercise (7%). These relationships were partly mediated by internalization of the thin ideal, body comparison, and subjective importance of achieving one's ‘ideal’ body and of avoiding one's ‘worst possible’ body. Interestingly, body dissatisfaction partly mediated the relationships involving SP but not SR.
Discussion
The results suggest that an underlying sensitivity to punishments, but not rewards, can manifest as a ‘fear of fatness’. Both of these motivational traits can increase the salience of self evaluations, and thus indirectly contribute to unhealthy body change attitudes and behaviours.

Exploring the cultural and social impacts on the requirements engineering processes-highlighting some problems challenging virtual team relationships with clients

Abstract:

Requirements engineering is a crucial phase in software development. Software development in a virtual domain adds another dimension to the process of requirements engineering. There has been growing interest in virtual teams, and more specifically in virtual software development. While structured software development methods are the obvious first choice for project managers to ensure a virtual software development team remains on track, the social and cultural aspects of requirements engineering cannot be ignored. These social aspects are especially important across different cultures, and have been shown to affect the success of an information system. The discussion in this paper is centred around the requirements engineering processes of a virtual team in a Thai Software House. This paper explains the issues and challenges of requirements engineering in a virtual domain from a social and cultural perspective. Project managers need to encourage a balance between structured methods and social aspects in requirements engineering for virtual team members. Cultural and social aspects influence the relationship between the virtual team and the client.

Thought processes associated with reluctance in gay men to be tested for HIV

This study explored the thought processes that are associated with reluctance in gay men to be tested for HIV antibodies. The sample comprised 97 men who had not been tested for at least four years; 69 had never been tested. They were asked to imagine that someone had suggested that they be tested very soon and to identify, from the list provided, any negative thoughts prompted by this suggestion. The most commonly reported thoughts were that testing was unnecessary because risks had not been taken, that it was unnecessary because there were no symptoms, and that there was no urgency to be tested. Data were explored by means of factor analysis and comparisons across subgroups differing in risk level. The results are interpreted as indicating the use of rationalizations to buttress a decision not to be tested, the powerful influence on HIV decision-making exerted by salient perceptible features, and the ‘status quo bias’. Techniques that could be used to encourage testing in gay men are discussed.

1948 and 1968 Czech refugee settlers in Australia : a comparison of the settlement and integration processes among two waves of settlers

Nearly eighteen years ago when I first became interested in the history and sociology of Australian immigration, I was particularly attracted by the fact and opportunity to incorporate immigration settlement, experience and accomplishments in my history teaching in secondary school. In particular it was the area of the settlement of Australia that needed a fuller understanding in the teaching of Australian history. By that I mean it was needed to show that there were many other ethnic groups besides the Anglo-Saxon group which had participated in the development of Australia since 1788. Since the end of World War II, the Australian population has doubled, the population structure and characteristics have changed and knowledge about the diverse groups forming the Australian nation is now sought. Sane ethnic groups, mainly the numerically large, have been studied and numerous reports are available. But many of the smaller groups have attracted little interest among Australian scholars. This was one of the reasons that I decided to research the behaviour of one of the smaller groups - the Czechs - to find out about their immigration history to Australia; their immigration processes such as re-settlement and re-establishment; and their community life since World War II. Because of the scarcity of written materials on Czechs in Australia, I had to rely on interviews, personal reminiscenses, letters and documents translated from the Czech language. I should like to express my gratitude to all people and officials of Czech ethnic organisations and clubs in Australia, who agreed to be interviewed and who provided me with documentary material so important for my work. Respecting the wishes of my interviewees their anonymity had to be preserved. In the course of my research, I have received substantial help and the encouragement from the Editor of the now extinct Czech language paper Newspaper Hlas domova, Mr. F.V., whose co-operation is gratefully recognised. I am also grateful to Associate Professor William D. Rubinstein for his help and encouragement in all stages of my work. The introductory part of the study is covered in Chapter One. She reasons for the need to increase Australia's population after World War II and an analysis of the development of settlement in Australia between 1947 and 1984 are discussed. The emigration of Czechs into Australia and their place in the post-war immigration scheme is introduced. To obtain an overview of how Czechs have emigrated around the world, the literature describing their settlement is compared. Also discussed in the literature on Czech settlement in Australia from an historical point of view. The studies on the concept of ethnicity and settlement in Australia are used to document the theoretical issues for an understanding of Australian society. This chapter also contains aspects of sources and research, shewing the processes of documentary research, interviews and related matters. In Chapter Two the history of Czech emigration is discussed, covering the period from the seventeenth to the twentieth century. The first contacts with Australia are highlighted, continuing into the inter-war period and finally the re-settlement of Czechs after World War II. To understand why Czechs left their ancestral country after World War II, the political situation in Czechoslovakia is analysed. The third chapter concentrates mainly in the 1948 wave of settlers, who left Czechoslovakia after the communist take-over in 1948. Their means of departure from their homeland, selection of Australia as a new homeland and their re-settlement and re-establishment are discussed. Their attitudes after their arrival and their later stages of their settlement are analysed. The formation of numerous Czech ethnic organisations which mushroomed between 1950 and 1954 led to an active community life which began to change about five years after their arrival. These charges led to disorganisation of Czech community's life. The causes of these changes which were influential for the failure of the 1948 group to establish a viable community in Australia are analysed. In Chapter Four the wave of 1968 is viewed, their arrival and settling is covered. The study of their group attitudes and formation of group institutions is the main part of this section. A comparison of my data of the two waves, 1948 and 1968, reveals the information that these two groups did not develop the harmonious relationship expected of them as members of the one ethnic group. Chapter Five discusses immigration typologies and concentrates on the differences between legal and illegal emigrants from the Czechoslovak point of view. The integration processes of Czechs and their incorporation into Australian society are discussed. The sixth chapter sums up the findings of this disertation and states the influences which were responsible for the divisions in Czech ethnic life in Australia in the 1980s.

Experiments with stochastic processes : facade subdivision based on wind motion

Constraint based tools for architectural design exploration need to satisfy aesthetic and functional criteria as well as combine discrete and continuous modes of exploration. In this paper, we examine the possibilities for stochastic processes in design space exploration.

Specifically, we address the application of a stochastic wind motion model to the subdivision of an external building envelope into smaller discrete components. Instead of deterministic subdivision constraints, we introduce explicit uncertainty into the system of subdivision. To address these aims, we develop a model of stochastic wind motion; create a subdivision scheme that is governed by the wind model and explore a design space of a facade subdivision problem. A discrete version of the facade, composed of light strips and panels, based on the bamboo elements deformed by continuous wind motion, is developed. The results of the experiments are presented in the paper.

Processes of task performance as measured by the assessment of motor and process skills (AMPS): a predictor of work-related outcomes for adults with schizophrenia?

Objective: To determine whether the processes of task performance as measured by the Assessment of Motor and Process Skills (AMPS) would discriminate between the employment levels of adults with schizophrenia. Participants: Twenty adults with schizophrenia who were engaged either in competitive employment, supported employment, prevocational training, or nonvocational activities, participated in this exploratory study. Methods: Each participant completed the AMPS, the Positive and Negative Syndrome Scale (PANSS), the Addiction Severity Index (ASI), and theWorker Role Interview (WRI) to gather data about their occupational performance, symptoms, drug / alcohol use, and psychosocial / environmental factors that might influence their work related outcomes. Results: Analysis revealed a moderate correlation between the level of employment and the global scores of the process skills scale in the AMPS. Conclusions: This should be seen as preliminary evidence that beyond the basic cognitive functions, processes of task performance may also be a predictor of work related outcomes for this population. The results also highlighted the importance of considering personal causation and worker roles when assessing the work capacities of these clients. Finally, findings supported the four levels of employment used in this study, which appeared to form a continuum from nonvocational activities, prevocational training, supported employment, through to competitive employment.

Tree façades : generative modelling with an axial branch rewriting system

The methods and algorithms of generative modelling can be improved when representing organic structures by the study of computational models of natural processes and their application to architectural design. In this paper, we present a study of the generation of branching structures and their application to the development of façade support systems. We investigate two types of branching structures, a recursive bifurcation model and an axial tree based L-system for the generation of façades. The aim of the paper is to capture not only the form but also the underlying principles of biomimicry found in branching. This is then tested, by their application to develop experimental façade support systems. The developed algorithms implement parametric variations for façade generation based on natural tree-like branching. The benefits of such a model are: ease of structural optimization, variations of support and digital fabrication of façade components.

Fire and its interaction with ecological processes in box-ironbark forests

Box-Ironbark forests extend across a swathe of northern Victoria on the inland side of the Great Dividing Range. Although extensively cleared and modified, they support a distinctive suite of plants and animals. Historical fire regimes in this ecosystem are largely unknown, as are the effects of fire on most of the biota. However, knowledge of the ecological attributes of plant species has been used to determine minimum and maximum tolerable fire intervals for this ecosystem to guide current fire management. Here, we consider the potential effects of planned fire in the context of major ecological drivers of the current box-ironbark forests: namely, the climate and physical environment; historical land clearing and fragmentation; and extractive land uses. We outline an experimental management and research project based on application of planned burns in different seasons (autumn, spring) and at different levels of burn cover (patchy, extensive). A range of ecological attributes will be monitored before and after burns to provide better understanding of the landscape-scale effects of fire in box-ironbark forests. Such integration of management and research is essential to address the many knowledge gaps in fire ecology, particularly in the context of massively increased levels of planned burning currently being implemented in Victoria.