The GP problem: quantifying gene-to-phenotype relationships

In this paper we refer to the gene-to-phenotype modeling challenge as the GP problem. Integrating information across levels of organization within a genotype-environment system is a major challenge in computational biology. However, resolving the GP problem is a fundamental requirement if we are to understand and predict phenotypes given knowledge of the genome and model dynamic properties of biological systems. Organisms are consequences of this integration, and it is a major property of biological systems that underlies the responses we observe. We discuss the E(NK) model as a framework for investigation of the GP problem and the prediction of system properties at different levels of organization. We apply this quantitative framework to an investigation of the processes involved in genetic improvement of plants for agriculture. In our analysis, N genes determine the genetic variation for a set of traits that are responsible for plant adaptation to E environment-types within a target population of environments. The N genes can interact in epistatic NK gene-networks through the way that they influence plant growth and development processes within a dynamic crop growth model. We use a sorghum crop growth model, available within the APSIM agricultural production systems simulation model, to integrate the gene-environment interactions that occur during growth and development and to predict genotype-to-phenotype relationships for a given E(NK) model. Directional selection is then applied to the population of genotypes, based on their predicted phenotypes, to simulate the dynamic aspects of genetic improvement by a plant-breeding program. The outcomes of the simulated breeding are evaluated across cycles of selection in terms of the changes in allele frequencies for the N genes and the genotypic and phenotypic values of the populations of genotypes.

Airborne Pinus pollen in the atmosphere of Brisbane, Australia and relationships with meteorological parameters

Relationships between weather parameters andairborne pollen loads of Pinus inBrisbane, Australia have been investigated overthe five-year period, June 1994–May 1999.Pinus pollen accounts for 4.5% of the annualairborne pollen load in Brisbane where thePinus season is confined to the winter months,July–early September. During the samplingperiod loads of 11–>100 grains m3 wererecorded on 24 days and 1–10 grains m3 on204 days. The onset and peak dates wereconsistent across each season, whereas the enddates varied. The onset of the Pinuspollen season coincided with the coolestaverage monthly temperatures (< 22°C),lowest rainfall (< 7mm), and four weeks afterdaily minimum temperatures fell to 5–9°Cin late autumn. Correlations obtained betweendaily airborne Pinus pollen counts andtemperature/rainfall parameters show thatdensities of airborne Pinus pollen arenegatively correlated with maximum temperature(p < 0.0001), minimum temperature (p < 0.0001)and rainfall (p < 0.05) during the mainpollination period. The mean duration of eachpollen season was 52 days; longer seasons wereshown to be directly related to lower averageseasonal maximum temperatures (r2 = 0.85,p = 0.025). These results signify that maximumand minimum temperatures are the majorparameters that influence the onset andduration of the Pinus pollen season inthe environs of Brisbane. Respiratory allergyis an important health issue in Brisbane,Australia, but it remains unknown whether ornot airborne Pinus pollen is acontributing factor.

An investigation into commitment in non-Western industrial marketing relationships

This paper reports an investigation into the antecedents of commitment in non-Western industrial marketing relationships. The authors draw the antecedents from extant literature and posit that commitment is related to trust (integrity and reliability), communication quality, conflict, and similarity (social, ethnic, and economic). It is further argued that trust mediates the effects of communication, conflict, and similarity on commitment. As an extension, the authors examine the moderating effects of normative contracts (an implicit understanding of roles and responsibilities) on the construct interrelationships. The hypotheses are tested using data collected from approximately 150 industrial marketing relationships sampled from overseas Chinese firms. The results generally support the authors' framework; however, the mediating hypotheses are not supported. There is evidence of systematic differences in the effects of the studied antecedents on commitment and trust. Furthermore, a multigroup analysis provides evidence of significant moderating effects due to contracting mode. The study provides new insights into the theory and practice of industrial marketing. (C) 2003 Elsevier Science Inc. All rights reserved.

On-line writing: a link to learning in a teacher education program

This paper examines the use of on-line discussion as a medium for learning in a pre-service teacher education program. As part of an Education Studies course student teachers engaged in a discussion of issues related to technology and equity in schools. The design of the task and the subsequent analysis of the on-line text were part of a research project investigating whether and how communications technology can be used to integrate and extend the learning of teacher education students. The main argument developed in the paper is that through the on-line activity distinctive sets of writing practices were created. These practices enabled students to make connections between the often disparate parts of teacher education programs-theory and practice, campus and school, research and experience. (C) 2002 Elsevier Science Ltd. All rights reserved.

Aligning school reform and teacher education reform in the middle years: An Australian case study

This paper discusses the development of a new Bachelor of Education (Middle Years of Schooling) at The University of Queensland. The middle years of schooling have increasingly been the focus of education reform initiatives in Australia, but this has not been accompanied by significant increases in the number of teacher education institutions offering specialised middle schooling-level teacher preparation programmes. Considering the rapidly changing social and economic context and the emergent state of middle schooling in Australia, the programme represented a conceptual and practical opportunity and challenge for The University of Queensland team. Working collaboratively, the team sought to design a teacher education preservice programme that was both responsive and generative: that is, responsive to local school contexts and to current educational research and reform at national and international levels; and generative of cutting-edge theories and practices associated with middle schooling, teachers' work, and teacher education. This paper focuses on one component of the Middle Years of Schooling Teacher Education programme at The University of Queensland; namely, the practicum. We first present the underlying principles of the practicum programme and then examine "dilemmas" that emerged early in the practicum. These issues and tensions were associated with the ideals of "middle years" philosophy and the pragmatics of school reform associated with that new approach. In this paper, and within this context, we explore what it means to be both responsive and generative, and describe how we as teacher educators negotiated between the extremes these terms implied.

Inter-relationships between rheumatoid arthritis and periodontal disease

This review considers the considerable similarities between periodontal disease and rheumatoid arthritis (RA). While the etiology of these two diseases may differ, the underlying pathogenic mechanisms are remarkably similar and it is possible that individuals manifesting both periodontitis and RA may suffer from a unifying underlying systemic dysregulation of the inflammatory response. In light of these findings, the implications for the use of disease-modifying medications in the management of these two chronic inflammatory conditions is apparent. Further longitudinal studies and medication-based intervention studies are required to determine just how closely these two conditions are allied.

Phylogenetic relationships of Hepatozoon (Haemogregarina) boigae Hepatozoon sp. Haemogregarina clelandi and Haemoproteus chelodina from Australian reptiles to other Apicomplexa based on cladistic analyses of ultrastructural and life-cycle characters

The phylogeny of representative haemozoan species of the phylum Apicomplexa was reconstructed by cladistic analyses of ultrastructural and life-cycle characteristics. The analysis incorporated 4 apicomplexans previously not included in phylogenetic reconstructions: Haemogregarina clelandi from the Brisbane River tortoise (Emydura signata), Hepatozoon sp. from the slaty grey snake (Stegonotus cucullatus), Hepatozoon (Haemogregarina) boigae from the brown tree snake (Boiga irregularis), and Haemoproteus chelodina from the saw-shelled tortoise (Elseya latisternum). There was no apparent correlation between parasite phylogeny and that of their vertebrate hosts, but there appeared to be some relationship between parasites and their intermediate hosts, suggestive of parasite/vector co-evolution.

Emergence of joint attention: Relationships between gaze following, social referencing, imitation, and naming in infancy

The authors investigated the extent to which the joint-attention behaviors of gaze following, social referencing, and object-directed imitation were related to each other and to infants vocabulary development in a sample of 60 infants between the ages of 8 and 14 months. Joint-attention skills and vocabulary development were assessed in a laboratory setting. Split-half reliability analyses on the joint-attention measures indicated that the tasks reliably assessed infants' capabilities. In the main analysis, no significant correlations were found among the joint-attention behaviors except for a significant relationship between gaze following and the number of names in infants' productive vocabularies. The overall pattern of results did not replicate results of previous studies (e.g., M. Carpenter, K. Nagell, & M. Tomasello, 1998) that found relationships between various emerging joint-attention behaviors.