Design Problems for Secondary Students

Are there different kinds of design problems? According to Brown and Chandrasekaran (1989), Class 1 design problems are open-ended, non-routine creative activities where the goals are ill-structured, and there is no effective design plan specifying the sequence of actions to take in producing a design model. Class 2 problems use existing, well-developed design and decomposition plans (e.g. designing a new automobile). Class 3 designs are routine where design and decomposition plans are known as well as customary actions taken to deal with failures (e.g., writing a computer program). Jonassen (2011) argued that problems vary in terms of structuredness, complexity, and context. On the structuredness and complexity continua, design problems tend to be the most ill-structured and complex. Brown and Chandrasekaran suggest that design problems may vary along a continuum from well-structured to ill-structured, depending upon the context in which they are solved. In formal, school contexts, design problems are often more constrained, allowing many fewer degrees of freedom in their representations, processes, or solutions and are therefore more well-structured

Genomic Diversity among Beijing and non-Beijing Mycobacterium tuberculosis Isolates from Myanmar

Background: The Beijing family of Mycobacterium tuberculosis is dominant in countries in East Asia. Genomic polymorphisms are a source of diversity within the M. tuberculosis genome and may account for the variation of virulence among M. tuberculosis isolates. Till date there are no studies that have examined the genomic composition of M. tuberculosis isolates from the high TB-burden country, Myanmar. Methodology/Principle Findings: Twenty-two M. tuberculosis isolates from Myanmar were screened on whole-genome arrays containing genes from M. tuberculosis H37Rv, M. tuberculosis CDC1551 and M. bovis AF22197. Screening identified 198 deletions or extra regions in the clinical isolates compared to H37Rv. Twenty-two regions differentiated between Beijing and non-Beijing isolates and were verified by PCR on an additional 40 isolates. Six regions (Rv0071-0074 [RD105], Rv1572-1576c [RD149], Rv1585c-1587c [RD149], MT1798-Rv1755c [RD152], Rv1761c [RD152] and Rv0279c) were deleted in Beijing isolates, of which 4 (Rv1572-1576c, Rv1585c-1587c, MT1798-Rv1755c and Rv1761c) were variably deleted among ST42 isolates, indicating a closer relationship between the Beijing and ST42 lineages. The TbD1 region, Mb1582-Mb1583 was deleted in Beijing and ST42 isolates. One M. bovis gene of unknown function, Mb3184c was present in all isolates, except 11 of 13 ST42 isolates. The CDC1551 gene, MT1360 coding for a putative adenylate cyclase, was present in all Beijing and ST42 isolates (except 1). The pks15/1 gene, coding for a putative virulence factor, was intact in all Beijing and non-Beijing isolates, except in ST42 and ST53 isolates. Conclusion: This study describes previously unreported deletions/extra regions in Beijing and non-Beijing M. tuberculosis isolates. The modern and highly frequent ST42 lineage showed a closer relationship to the hypervirulent Beijing lineage than to the ancient non-Beijing lineages. The pks15/1 gene was disrupted only in modern non-Beijing isolates. This is the first report of an in-depth analysis on the genomic diversity of M. tuberculosis isolates from Myanmar

Effects of semantically structured hypertextual knowledge bases on user knowledge structures

Some hypertext researchers and designers believe that hypertext information structures should reflect the structures of human memory and that by empirically deriving and then mapping the semantic structure of information onto hypertext and explicitly illustrating that structure in the hypertext interface will result in greater changes in the knowledge structures of the users (Jonassen, 1990, 1991b; Lambiotte et al., 1989; McAleese, 1990; McDonald, Paap and McDonald, 1990). This chapter introduces techniques for ascertaining an expert’s knowledge structure and mapping it onto hypertext. It then reviews the results of an ongoing series of studies that test these ideas. The studies show that merely illustrating content structures in the interface is not sufficient for helping learners acquire that structure. Rather, it is the nature of the processing task and goals for learning whilst interacting with a hypertext that determines the effects of its use on learners’ knowledge structures

Pulmonary perfusion with oxygenated blood or custodiol HTK solution during cardiac surgery for postoperative pulmonary function in COPD patients: a trial protocol for the randomized, clinical, parallel group, assessor and data analyst blinded Pulmonary Protection Trial

BACKGROUND: Five to thirty percent of patients undergoing cardiac surgery present with chronic obstructive pulmonary disease (COPD) and have a 2- to 10-fold higher 30-day mortality risk. Cardiopulmonary bypass (CPB) creates a whole body systemic inflammatory response syndrome (SIRS) that could impair pulmonary function. Impaired pulmonary function can, however, be attenuated by pulmonary perfusion with oxygenated blood or custodiol HTK (histidine-tryptophan-ketoglutarate) solution. METHODS/DESIGN: The Pulmonary Protection Trial (PP-Trial) randomizes 90 patients undergoing CPB-dependent cardiac surgery to evaluate whether pulmonary perfusion with oxygenated blood or custodiol HTK solution reduces postoperative pulmonary dysfunction in COPD patients. Further, we aim for a non-randomized evaluation of postoperative pulmonary function after transcatheter aortic-valve implantation (TAVI). The primary outcome measure is the oxygenation index measured from anesthesia induction to the end of surgery and until 24 hours after anesthesia induction for a total of six evaluations. DISCUSSION: Patients with COPD may be impaired by hypoxemia and SIRS. Thus, prolonged recovery and even postoperative complications and death may be reflected by the degree of hypoxemia and SIRS. The limited sample size does not aim for confirmatory conclusions on mortality, cardiovascular complications or risk of pneumonia and sepsis, but the PP-Trial is considered an important feasibility trial paving the road for a multicenter confirmatory trial. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01614951

From classroom reality to virtual classroom: the role of teacher-created scripts in the development of classroom simulation technology

This paper describes a specific kind of teacher narrative (the teacher created script) to support the design of a classroom simulation to be used in pre-service teacher education. We intend to share our experiences in exploring and developing the kind of narrative text which can be developed from a large reservoir of ethnographically generated data collected from the teachers and classrooms we have closely observed and documented over the last two decades. In particular, we explore the role which these narratives play within the development of the kind of classroom simulation we have produced. Reflection has long been acknowledged as a useful process for teachers to engage with. Also, the notion of formalising such reflections through writing has been acknowledged as a way to share, refine and articulate teaching practice. As stated by Barth (2001:66) “…with written words come the innermost secrets of schools”. This prototype simulation allows the user to adopt the role of a Kindergarten teacher using a daily literacy teaching episode we refer to as “days of the week” and encourages the user to reflect upon the decisions they make about the organisation and implementation of this recurring teaching experience. The range of options that occur in this simulation stem from the teacher-created script we developed drawing from our own teaching experiences and classroom-based research to shape this virtual classroom

seeMotif: exploring and visualizing sequence motifs in 3D structures

Sequence motifs are important in the study of molecular biology. Motif discovery tools efficiently deliver many function related signatures of proteins and largely facilitate sequence annotation. As increasing numbers of motifs are detected experimentally or predicted computationally, characterizing the functional roles of motifs and identifying the potential synergetic relationships between them are important next steps. A good way to investigate novel motifs is to utilize the abundant 3D structures that have also been accumulated at an astounding rate in recent years. This article reports the development of the web service seeMotif, which provides users with an interactive interface for visualizing sequence motifs on protein structures from the Protein Data Bank (PDB). Researchers can quickly see the locations and conformation of multiple motifs among a number of related structures simultaneously. Considering the fact that PDB sequences are usually shorter than those in sequence databases and/or may have missing residues, seeMotif has two complementary approaches for selecting structures and mapping motifs to protein chains in structures. As more and more structures belonging to previously uncharacterized protein families become available, combining sequence and structure information gives good opportunities to facilitate understanding of protein functions in large-scale genome projects. Available at: http://seemotif.csie.ntu.edu.tw,http://seemotif.ee.ncku.edu.tw or http://seemotif.csbb.ntu.edu.tw

Structured evaluation of virtual environments for special-needs education

This paper describes the development of a structured approach to evaluate experiential and communication virtual learning environments (VLEs) designed specifically for use in the education of children with severe learning difficulties at the Shepherd special needs school in Nottingham, UK. Constructivist learning theory was used as a basis for the production of an evaluation framework, used to evaluate the design of three VLEs and how they were used by students with respect to this learning theory. From an observational field study of student-teacher pairs using the VLEs, 18 behaviour categories were identified as relevant to five of the seven constructivist principles defined by Jonassen (1994). Analysis of student-teacher behaviour was used to provide support for, or against, the constructivist principles. The results show that the three VLEs meet the constructivist principles in very different ways and recommendations for design modifications are put forward

Oxalate-Induced Damage to Renal Tubular Cells

Our own studies and those of others have shown that the incidence of calcium oxalate stones and plaques is markedly increased by nephrotoxins. The possible role of oxalate as a nephrotoxin has not been fully appreciated. However, recent studies in experimental animals and in cultured cells support this possibility. The results of these studies led us to hypothesize that hyperoxaluria promotes stone formation in several ways: by providing a substrate for the formation of the most common form of renal stones, calcium oxalate stones, and by inducing damage to renal epithelial cells. Damaged cells in turn would produce an environment favorable for crystal retention and provide membranous debris that promotes crystal nucleation, aggregation and adherence. The present report summarizes evidence for oxalate nephrotoxicity and discusses the potential importance of oxalate toxicity in the pathogenesis of stone disease