22 resultados para Retaining
em University of Queensland eSpace - Australia
Resumo:
Frequent calls for more male teachers are being made in English-speaking countries. Many of these calls are based upon the fact that the teaching profession has become (even more) 'feminized' and the presumption that this has had negative effects for the education of boys. The employment of more male teachers is sometimes suggested as a way to re-masculinize schools so they become more 'boy-friendly' and thus contribute to improving boys' school performance. The focus of this paper is on an Australian education policy document in the state of Queensland that is concerned with the attraction, recruitment and retention of male teachers in the government education system. It considers the failure of this document, as with many of the calls for more male teachers, to take into account complex matters of gender raised by feminism and the sociology of masculinities. The paper then critiques the primary argument given for the need for more male teachers: that is, that male teachers provide boys with much needed role models.
Resumo:
This paper highlights the importance of design expertise, for designing liquid retaining structures, including subjective judgments and professional experience. Design of liquid retaining structures has special features different from the others. Being more vulnerable to corrosion problem, they have stringent requirements against serviceability limit state of crack. It is the premise of the study to transferring expert knowledge in a computerized blackboard system. Hybrid knowledge representation schemes, including production rules, object-oriented programming, and procedural methods, are employed to express engineering heuristics and standard design knowledge during the development of the knowledge-based system (KBS) for design of liquid retaining structures. This approach renders it possible to take advantages of the characteristics of each method. The system can provide the user with advice on preliminary design, loading specification, optimized configuration selection and detailed design analysis of liquid retaining structure. It would be beneficial to the field of retaining structure design by focusing on the acquisition and organization of expert knowledge through the development of recent artificial intelligence technology. (C) 2003 Elsevier Ltd. All rights reserved.
Resumo:
The design of liquid-retaining structures involves many decisions to be made by the designer based on rules of thumb, heuristics, judgement, codes of practice and previous experience. Structural design problems are often ill structured and there is a need to develop programming environments that can incorporate engineering judgement along with algorithmic tools. Recent developments in artificial intelligence have made it possible to develop an expert system that can provide expert advice to the user in the selection of design criteria and design parameters. This paper introduces the development of an expert system in the design of liquid-retaining structures using blackboard architecture. An expert system shell, Visual Rule Studio, is employed to facilitate the development of this prototype system. It is a coupled system combining symbolic processing with traditional numerical processing. The expert system developed is based on British Standards Code of Practice BS8007. Explanations are made to assist inexperienced designers or civil engineering students to learn how to design liquid-retaining structures effectively and sustainably in their design practices. The use of this expert system in disseminating heuristic knowledge and experience to practitioners and engineering students is discussed.
Resumo:
Owing to the high degree of vulnerability of liquid retaining structures to corrosion problems, there are stringent requirements in its design against cracking. In this paper, a prototype knowledge-based system is developed and implemented for the design of liquid retaining structures based on the blackboard architecture. A commercially available expert system shell VISUAL RULE STUDIO working as an ActiveX Designer under the VISUAL BASIC programming environment is employed. Hybrid knowledge representation approach with production rules and procedural methods under object-oriented programming are used to represent the engineering heuristics and design knowledge of this domain. It is demonstrated that the blackboard architecture is capable of integrating different knowledge together in an effective manner. The system is tailored to give advice to users regarding preliminary design, loading specification and optimized configuration selection of this type of structure. An example of application is given to illustrate the capabilities of the prototype system in transferring knowledge on liquid retaining structure to novice engineers. (C) 2004 Elsevier Ltd. All rights reserved.
Resumo:
Objective To describe the attitudes to their work and career of those Australian veterinarians who work with horses. Method Questionnaires were mailed to 866 veterinarians who had been identified as working with horses, and 87% were completed and returned. Data were entered onto Excel spreadsheets, and analysed using the SAS System for Windows. Results The main attractions of veterinary work with horses were the horses themselves and the equine industries, but working outdoors and with rewarding clients, and the satisfaction of successful outcomes were attractions for many. The list of disadvantages was longer, and included unreasonable and disagreeable clients as well as those who provided inadequate facilities, could not control their horses or did not care for them. The physical demands and risks of injury, the amount of time required, low rates of return and difficulties in collecting payment, were other major disadvantages. Some mentioned concerns about litigation, unethical behaviour, and recruiting and retaining veterinarians competent with horses. For many in mixed practice, the difficulties in affording modern equipment, and of developing and maintaining their own competence with horses, was a real concern. More than three-quarters of the respondents reported that their careers had lived up to expectations and that they would become veterinarians again; 70% of equine veterinarians would become an equine veterinarian again. Almost all (93%) of the respondents were either very glad, or 'generally glad though with some misgivings' that they had done the veterinary course. Older veterinarians reported suffering less stress, and being more content with their career, than younger colleagues. Conclusions The advantages of doing veterinary work with horses outweigh the disadvantages for most veterinarians, especially those well advanced in their careers.
Resumo:
Arguably, living and working in rural communities can pose significant challenges for human service practitioners - challenges that are different from those encountered by their urban counterparts. Human services employers, like many other employers in rural areas, have difficulty in recruiting and retaining staff. There is now considerable evidence to support the notion that rural and remote practice constitutes a different and distinct form of practice and has undergone significant changes over the past decade. Living and working in rural communities means that practitioners are not only influenced by the rural and remote context of practice, they are also part of that context. Given the difficulty encountered in attracting and retaining rural practitioners and the changes in this area, an important question which emerges is: How can practitioners best be prepared for this work through largely urban based social work and human service education? The multifaceted and multilayered complexities in rural practice requires creativity, improvisation and a capacity for 'integrative thinking' (Martinez-Brawley 2002). This paper discusses six elements of newer forms of rural and remote practice and how they might be most effectively addressed through social work and human service curricula. An education model which integrates these elements and other principles for rural practice is proposed.
Resumo:
This article argues that since 2000 successive Croatian governments have shown themselves increasingly dedicated to reforming civil-military relations. However, their efforts have been hampered by four key obstacles. First, the need to implement defence reforms in the context of an unwieldy set of civil-military relationships, political and institutional rivalries, a lack of civil and military defence expertise and a continuing legacy of politicisation. Second, the need to cut defence spending as a proportion of the overall budget whilst taking on new military roles and improving the capability of the armed forces. Third, the need to balance the demands of the NATO accession process while implementing a balanced and fundamental reform of the armed forces as a whole. Finally, the need to implement root and branch personnel reforms and downsizing in the OSRH while simultaneously recruiting and retaining quality personnel and addressing the wider social issue of unemployment.
Resumo:
Weather damage reduces the value of commercial mungbean, but hard-seededness can reduce the level of damage. However, attempts to breed large- and hard-seeded mungbean varieties have been unsuccessful. To understand the relationship between seed weight and hard-seededness, these traits were investigated using a quantitative trait loci (QTL) mapping approach with a recombinant inbred population derived from a cross between a completely soft-seeded variety and a completely hard-seeded genotype. The two parental genotypes also had a sixfold difference in seed weight. QTL analyses revealed four loci for hard-seededness and I I loci for seed weight. Two of the hardseededness loci co-localized with seed weight QTL. When seed weight was used as a covariate in the analysis of hard-seededness from the field data, two of the four hard-seeded QTL remained significant with the effect at one of these remaining unchanged. These results explain why retaining hard-seededness in large seeded mungbean lines has been unsuccessful. The existence of a persistent locus, however, indicated that breeding large and persistently hard-seeded varieties of mungbean may be possible.
Resumo:
Response of an aerobic upflow sludge blanket (AUSB) reactor system to the changes in operating conditions was investigated by varying two principle operating variables: the oxygenation pressure and the flow recirculation rate. The oxygenation pressure was varied between 0 and 25 psig (relative), while flow recirculation rates were between 1,300 and 600% correspondingly. The AUSB reactor system was able to handle a volumetric loading of as high as 3.8 kg total organic carbon (TOC)/m(3) day, with a removal efficiency of 92%. The rate of TOC removal by AUSB was highest at a pressure of 20 psig and it decreased when the pressure was increased to 25 psig and the flow recirculation rate was reduced to 600%. The TOC removal rate also decreased when the operating pressure was reduced to 0 and 15 psig, with corresponding increase in flow recirculation rates to 1,300 and 1,000%, respectively. Maintenance of a high dissolved oxygen level and a high flow recirculation rate was found to improve the substrate removal capacity of the AUSB system. The AUSB system was extremely effective in retaining the produced biomass despite a high upflow velocity and the overall sludge yield was only 0.24-0.32 g VSS/g TOC removed. However, the effluent TOC was relatively high due to the system's operation at a high organic loading.
Resumo:
We report the cloning and characterization in tobacco and Arabidopsis of a Vigna radiata L. (mung bean) promoter that controls the expression of VR-ACS1, an auxin-inducible ACC synthase gene. The VR-ACS1 promoter exhibits a very unusual behavior when studied in plants different from its original host, mung bean. GUS and luciferase in situ assays of transgenic plants containing VR-ACS1 promoter fusions show strong constitutive reporter gene expression throughout tobacco and Arabidopsis development. In vitro quantitative analyses show that transgenic plants harboring VR-ACS1 promoter-reporter constructs have on average 4-6 fold higher protein and activity levels of both reporter genes than plants transformed with comparable CaMV 35S promoter fusions. Similar transcript levels are present in VR-ACS1 and CaMV 35S promoter lines, suggesting that the high levels of gene product observed for the VR-ACS1 promoter are the combined result of transcriptional and translational activation. All tested deletion constructs retaining the core promoter region can drive strong constitutive promoter activity in transgenic plants. This is in contrast to mung bean, where expression of the native VR-ACS1 gene is almost undetectable in plants grown under normal conditions, but is rapidly and highly induced by a variety of stimuli. The constitutive behavior of the VR-ACS1 promoter in heterologous hosts is surprising, suggesting that the control mechanisms active in mung bean are impaired in tobacco and Arabidopsis. The 'aberrant' behavior of the VR-ACS1 promoter is further emphasized by its failure to respond to auxin and cycloheximide in heterologous hosts. VR-ACS1 promoter regulatory mechanisms seem to be different from all previously characterized auxin-inducible promoters.
Resumo:
Given that an important functional attribute of stem cells in vivo is their ability to sustain tissue regeneration, we set out to establish a simple and easy technique to assess this property from candidate populations of human keratinocyte stem cells in an in vivo setting. Keratinocytes were inoculated into devitalized rat tracheas and transplanted subcutaneously into SCID mice, and the epithelial lining regenerated characterized to establish the validity of this heterotypic model. Furthermore, the rate and quality of epidermal tissue reconstitution obtained from freshly isolated unfractionated vs. keratinocyte stem cell-enriched populations was tested as a function of (a) cell numbers inoculated; and (b) the inclusion of irradiated support keratinocytes and dermal cells. Rapid and sustained epidermal tissue regeneration from small numbers of freshly isolated human keratinocyte stem cells validates the utilization of this simple and reliable model system to assay for enrichment of epidermal tissue-reconstituting cells.
Resumo:
The molecular mechanisms behind the entry of the primordial follicle into the growing follicle pool remain poorly understood. To investigate this process further, a microarray-based comparison was undertaken between 2-day postpartum mouse ovaries consisting of primordial follicles/naked oocytes only and those with both primordial follicles and newly activated follicles (7-day postpartum). Gene candidates identified included the chemoattractive cytokine stromal derived factor-1 (SDF1) and its receptor CXCR4. SDF1 and CXCR4 have been implicated in a variety of physiological processes including the migration of embryonic germ cells to the gonads. SDF1-alpha expression increased with the developmental stage of the follicle. Embryonic expression was found to be dichotomous post-genii cell migration, with low expression in the female. Immunohistochemical studies nonetheless indicate that the autocrine pattern of expression ligand and receptor begins during embryonic life. Addition of recombinant SDF1-alpha to neonatal mouse ovaries in vitro resulted in significantly higher follicle densities than for control ovaries. TUNEL analysis indicated no detectable difference in populations of apoptotic cells of treated or control ovaries. Treated ovaries also contained a significantly lower percentage of activated follicles as determined by measurement of oocyte diameter and morphological analysis. Treatment of cultured ovaries with an inhibitor of SDF1-alpha, AMD3100, ablated the effect of SDF1-alpha. By retaining follicles in an unactivated state, SDF1/CXCR4 signaling may play an important role in maintaining the size and longevity of the primordial follicle pool. (c) 2006 Elsevier Inc. All rights reserved.