184 resultados para breeding line


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Significant wheel-rail dynamic forces occur because of imperfections in the wheels and/or rail. One of the key responses to the transmission of these forces down through the track is impact force on the sleepers. Dynamic analysis of nonlinear systems is very complicated and does not lend itself easily to a classical solution of multiple equations. Trying to deduce the behaviour of track components from experimental data is very difficult because such data is hard to obtain and applies to only the particular conditions of the track being tested. The finite element method can be the best solution to this dilemma. This paper describes a finite element model using the software package ANSYS for various sized flat defects in the tread of a wheel rolling at a typical speed on heavy haul track. The paper explores the dynamic response of a prestressed concrete sleeper to these defects.

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Knowledge of cable parameters has been well established but a better knowledge of the environment in which the cables are buried lags behind. Research in Queensland University of Technology has been aimed at obtaining and analysing actual daily field values of thermal resistivity and diffusivity of the soil around power cables. On-line monitoring systems have been developed and installed with a data logger system and buried spheres that use an improved technique to measure thermal resistivity and diffusivity over a short period. Results based on long term continuous field data are given. A probabilistic approach is developed to establish the correlation between the measured field thermal resistivity values and rainfall data from weather bureau records. This data from field studies can reduce the risk in cable rating decisions and provide a basis for reliable prediction of “hot spot” of an existing cable circuit

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The implementation guide for the surveillance of CLABSI in intensive care units (ICU) was produced by the Healthcare Associated Infection (HAI) Technical Working Group of the Australian Commission on Safety and Quality in Health Care(ACSQHC), and endorsed by the ACSQHC HAI Advisory Committee. State surveillance units, the ACSQHC and the Australian and New Zealand Intensive Care Society (ANZICS) have representatives on the Technical Working Group, and have provided input into this document.

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In this paper, a new comprehensive planning methodology is proposed for implementing distribution network reinforcement. The load growth, voltage profile, distribution line loss, and reliability are considered in this procedure. A time-segmentation technique is employed to reduce the computational load. Options considered range from supporting the load growth using the traditional approach of upgrading the conventional equipment in the distribution network, through to the use of dispatchable distributed generators (DDG). The objective function is composed of the construction cost, loss cost and reliability cost. As constraints, the bus voltages and the feeder currents should be maintained within the standard level. The DDG output power should not be less than a ratio of its rated power because of efficiency. A hybrid optimization method, called modified discrete particle swarm optimization, is employed to solve this nonlinear and discrete optimization problem. A comparison is performed between the optimized solution based on planning of capacitors along with tap-changing transformer and line upgrading and when DDGs are included in the optimization.

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A short 27 mins docudrama film. The Brisbane Line is a neo noir drama-documentary depicting the forgotten history surrounding the subtropical capital of Queensland, Australia. Set in the shadows of this sunshine city's unsolved crime, the film explores gaps between fact and fiction, memory and myth and excavates Brisbane's original sin [from DVD container]. The Brisbane Line is a film noir about the 1940s police force & corruption in Brisbane. The film is a creative research output, screened at Tribal Cinemas, Brisbane on the 8th November 2011.

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The project examined the responsiveness of the telenursing service provided by the Child Health Line (hereinafter referred to as CHL). It aimed to provide an account of population usage of the service, the call request types and the response of the service to the calls. In so doing, the project extends the current body of knowledge pertaining to the provision of parenting support through telenursing. Approximately 900 calls to the CHL were audio-recorded over the December 2005-2006 Christmas-New Year period. A protocol was developed to code characteristics of the call, the interactional features between the caller and nurse call-taker, and the extent to which there was (a) agreement on problem definition and the plan of action and (b) interactional alignment between nurse and caller. A quantitative analysis examined the frequencies of the main topics covered in calls to the CHL and any statistical associations between types of calls, length of calls and nurse-caller alignment. In addition, a detailed qualitative analysis was conducted on a subset of calls dealing with the nurse management of calls seeking medical advice and information. Key findings include: • Overall, 74% of the calls discussed parenting and child development issues, 48% discussed health/medical issues, and 16% were information-seeking calls. • More specifically: o 21% discussed health/medical and parenting and child development issues. o 3% discussed parenting and information-seeking issues. o 5% discussed health/medical, parenting/development and information issues. o 18% exclusively focussed on health and medical issues and therefore were outside the remit of the intended scope of the CHL. These calls caused interactional dilemmas for the nurse call-takers as they simultaneously dealt with parental expectations for help and the CHL guidelines indicating that offering medical advice was outside the remit of the service. • Most frequent reasons for calling were to discuss sleep, feeding, normative infant physical functions and parenting advice. • The average length of calls to the CHL was 7 minutes. • Longer calls were more likely to involve nurse call-takers giving advice on more than one topic, the caller displaying strong emotions, the caller not specifically providing the reason for the call, and the caller discussing parenting and developmental issues. • Shorter calls were characterised by the nurse suggesting that the child receive immediate medical attention, the nurse emphasising the importance or urgency of the plan of action, the caller referring to or requesting confirmation of a diagnosis, and caller and nurse call-taker discussion of health and medical issues. • The majority of calls, 92%, achieved parent-nurse alignment by the conclusion of the call. However, 8% did not. • The 8% of calls that were not aligned require further quantitative and qualitative investigation of the interactional features. The findings are pertinent in the current context where Child Health Line now resides within 13HEALTH. These findings indicate: 1. A high demand for parenting advice. 2. Nurse call-takers have a high level of competency in dealing with calls about parenting and normal child development, which is the remit of the CHL. 3. Nurse call-takers and callers achieve a high degree of alignment when both parties agree on a course of action. 4. There is scope for developing professional practice in calls that present difficulties in terms of call content, interactional behaviour and call closure. Recommendations of the project: 1. There are numerous opportunities for further research on interactional aspects of calls to the CHL, such as further investigations of the interactional features and the association of the features to alignment and nonalignment. The rich and detailed insights into the patterns of nurse-parent interactions were afforded by the audio-recording and analysis of calls to the CHL. 2. The regular recording of calls would serve as a way of increasing understanding of the type and nature of calls received, and provide a valuable training resource. Recording and analysing calls to CHL provides insight into the operation of the service, including evidence about the effectiveness of triaging calls. 3. Training in both recognising and dealing with problem calls may be beneficial. For example, calls where the caller showed strong emotion, appeared stressed, frustrated or troubled were less likely to be rated as aligned calls. In calls where the callers described being ‘at their wits end’, or responded to each proposed suggestion with ‘I’ve tried that’, the callers were fairly resistant to advice-giving. 4. Training could focus on strategies for managing calls relating to parenting support and advice, and parental well-being. The project found that these calls were more likely to be rated as being nonaligned. 5. With the implementation of 13HEALTH, future research could compare nurse-parent interaction following the implementation of triaging. Of the calls, 21% had both medical and parenting topics discussed and 5.3% discussed medical, parenting and information topics. Added to this, in 12% of calls, there was ambiguity between the caller and nurse call-taker as to whether the problem was medical or behavioural.

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A pressing cost issue facing construction is the procurement of off-site pre-manufactured assemblies. In order to encourage Australian adoption of off-site manufacture (OSM), a new approach to underlying processes is required. The advent of object oriented digital models for construction design assumes intelligent use of data. However, the construction production system relies on traditional methods and data sources and is expected to benefit from the application of well-established business process management techniques. The integration of the old and new data sources allows for the development of business process models which, by capturing typical construction processes involving OSM, provides insights into such processes. This integrative approach is the foundation of research into the use of OSM to increase construction productivity in Australia. The purpose of this study is to develop business process models capturing the procurement, resources and information flow of construction projects. For each stage of the construction value chain, a number of sub-processes are identified. Business Process Modelling Notation (BPMN), a mainstream business process modelling standard, is used to create base-line generic construction process models. These models identify OSM decision-making points that could provide cost reductions in procurement workflow and management systems. This paper reports on phase one of an on-going research aiming to develop a proto-type workflow application that can provide semi-automated support to construction processes involving OSM and assist in decision-making in the adoption of OSM thus contributing to a sustainable built environment.

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The steady problem of free surface flow due to a submerged line source is revisited for the case in which the fluid depth is finite and there is a stagnation point on the free surface directly above the source. Both the strength of the source and the fluid speed in the far field are measured by a dimensionless parameter, the Froude number. By applying techniques in exponential asymptotics, it is shown that there is a train of periodic waves on the surface of the fluid with an amplitude which is exponentially small in the limit that the Froude number vanishes. This study clarifies that periodic waves do form for flows due to a source, contrary to a suggestion by Chapman & Vanden-Broeck (2006, J. Fluid Mech., 567, 299--326). The exponentially small nature of the waves means they appear beyond all orders of the original power series expansion; this result explains why attempts at describing these flows using a finite number of terms in an algebraic power series incorrectly predict a flat free surface in the far field.

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This work has led to the development of empirical mathematical models to quantitatively predicate the changes of morphology in osteocyte-like cell lines (MLO-Y4) in culture. MLO-Y4 cells were cultured at low density and the changes in morphology recorded over 11 hours. Cell area and three dimensional shape features including aspect ratio, circularity and solidity were then determined using widely accepted image analysis software (ImageJTM). Based on the data obtained from the imaging analysis, mathematical models were developed using the non-linear regression method. The developed mathematical models accurately predict the morphology of MLO-Y4 cells for different culture times and can, therefore, be used as a reference model for analyzing MLO-Y4 cell morphology changes within various biological/mechanical studies, as necessary.

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Several approaches have been introduced in the literature for active noise control (ANC) systems. Since the filtered-x least-mean-square (FxLMS) algorithm appears to be the best choice as a controller filter, researchers tend to improve performance of ANC systems by enhancing and modifying this algorithm. This paper proposes a new version of the FxLMS algorithm, as a first novelty. In many ANC applications, an on-line secondary path modeling method using white noise as a training signal is required to ensure convergence of the system. As a second novelty, this paper proposes a new approach for on-line secondary path modeling on the basis of a new variable-step-size (VSS) LMS algorithm in feed forward ANC systems. The proposed algorithm is designed so that the noise injection is stopped at the optimum point when the modeling accuracy is sufficient. In this approach, a sudden change in the secondary path during operation makes the algorithm reactivate injection of the white noise to re-adjust the secondary path estimate. Comparative simulation results shown in this paper indicate the effectiveness of the proposed approach in reducing both narrow-band and broad-band noise. In addition, the proposed ANC system is robust against sudden changes of the secondary path model.

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Starting from the study at the beginning of the East German "Heterosisfeldversuch", where PANICKE et al. (1975) considered the possibilities of a targeted use of inbreeding and heterotic effects, we show and discuss results of inbreeding studies in the USA dairy cattle breeding. Several research groups worldwide presented effective tools for managing inbreeding in dairy cattle. Their efforts underline the need of inbreeding studies. Contemplating inbreeding is necessary for any breeding decision to avoid inbreeding depression and for improved genetic analyses, e.g. in QTL- estimation. A novel methodology (HERNANDEZ-SANCHEZ et al., 2004a and b) is suggested for estimating inbreeding at the three levels of population, individual and locus.

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The Flightless Cormorant Phalacrocorax harrisi is restricted to c. 400 km of the western coastline of the Galápagos archipelago coinciding with the local occurrence of seasonal upwelling of oceanic currents. Individuals frequently make more than one breeding attempt per year, usually change mates, and when juveniles are raised, females desert them to the further care of their mates who complete the rearing alone. Here we report data from a ten-year historical study of a colony stretching c.2 km along the coast-line and representing c. 12% of the total population of the species. The number of clutches laid and juveniles fledged were linked to the occurrence of cold water in off-shore foraging grounds. Most Flightless Cormorants have attachments to local stretches of coastline several hundred metres long. However, a few birds travelled many kilometres, including between colonies, sometimes over open sea. We show that males invest more in nest-building and feeding of the offspring than their mates, and we relate this to the (presumed) in-bred nature of the colony and to male and female reproductive strategies. Our data validate a published demographic model of the species (Valle 1995).

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The giant freshwater prawn (Macrobrachium rosenbergii) or GFP is one of the most important freshwater crustacean species in the inland aquaculture sector of many tropical and subtropical countries. Since the 1990’s, there has been rapid global expansion of freshwater prawn farming, especially in Asian countries, with an average annual rate of increase of 48% between 1999 and 2001 (New, 2005). In Vietnam, GFP is cultured in a variety of culture systems, typically in integrated or rotational rice-prawn culture (Phuong et al., 2006) and has become one of the most common farmed aquatic species in the country, due to its ability to grow rapidly and to attract high market price and high demand. Despite potential for expanded production, sustainability of freshwater prawn farming in the region is currently threatened by low production efficiency and vulnerability of farmed stocks to disease. Commercial large scale and small scale GFP farms in Vietnam have experienced relatively low stock productivity, large size and weight variation, a low proportion of edible meat (large head to body ratio), scarcity of good quality seed stock. The current situation highlights the need for a systematic stock improvement program for GFP in Vietnam aimed at improving economically important traits in this species. This study reports on the breeding program for fast growth employing combined (between and within) family selection in giant freshwater prawn in Vietnam. The base population was synthesized using a complete diallel cross including 9 crosses from two local stocks (DN and MK strains) and a third exotic stock (Malaysian strain - MY). In the next three selection generations, matings were conducted between genetically unrelated brood stock to produce full-sib and (paternal) half-sib families. All families were produced and reared separately until juveniles in each family were tagged as a batch using visible implant elastomer (VIE) at a body size of approximately 2 g. After tags were verified, 60 to 120 juveniles chosen randomly from each family were released into two common earthen ponds of 3,500 m2 pond for a grow-out period of 16 to 18 weeks. Selection applied at harvest on body weight was a combined (between and within) family selection approach. 81, 89, 96 and 114 families were produced for the Selection line in the F0, F1, F2 and F3 generations, respectively. In addition to the Selection line, 17 to 42 families were produced for the Control group in each generation. Results reported here are based on a data set consisting of 18,387 body and 1,730 carcass records, as well as full pedigree information collected over four generations. Variance and covariance components were estimated by restricted maximum likelihood fitting a multi-trait animal model. Experiments assessed performance of VIE tags in juvenile GFP of different size classes and individuals tagged with different numbers of tags showed that juvenile GFP at 2 g were of suitable size for VIE tags with no negative effects evident on growth or survival. Tag retention rates were above 97.8% and tag readability rates were 100% with a correct assignment rate of 95% through to mature animal size of up to 170 g. Across generations, estimates of heritability for body traits (body weight, body length, cephalothorax length, abdominal length, cephalothorax width and abdominal width) and carcass weight traits (abdominal weight, skeleton-off weight and telson-off weight) were moderate and ranged from 0.14 to 0.19 and 0.17 to 0.21, respectively. Body trait heritabilities estimated for females were significantly higher than for males whereas carcass weight trait heritabilities estimated for females and males were not significantly different (P > 0.05). Maternal and common environmental effects for body traits accounted for 4 to 5% of the total variance and were greater in females (7 to 10%) than in males (4 to 5%). Genetic correlations among body traits were generally high in both sexes. Genetic correlations between body and carcass weight traits were also high in the mixed sexes. Average selection response (% per generation) for body weight (transformed to square root) estimated as the difference between the Selection and the Control group was 7.4% calculated from least squares means (LSMs), 7.0% from estimated breeding values (EBVs) and 4.4% calculated from EBVs between two consecutive generations. Favourable correlated selection responses (estimated from LSMs) were detected for other body traits (12.1%, 14.5%, 10.4%, 15.5% and 13.3% for body length, cephalothorax length, abdominal length, cephalothorax width and abdominal width, respectively) over three selection generations. Data in the second selection generation showed positive correlated responses for carcass weight traits (8.8%, 8.6% and 8.8% for abdominal weight, skeleton-off weight and telson-off weight, respectively). Data in the third selection generation showed that heritability for body traits were moderate and ranged from 0.06 to 0.11 and 0.11 to 0.22 at weeks 10 and 18, respectively. Body trait heritabilities estimated at week 10 were not significantly lower than at week 18. Genetic correlations between body traits within age and genetic correlations for body traits between ages were generally high. Overall our results suggest that growth rate responds well to the application of family selection and carcass weight traits can also be improved in parallel, using this approach. Moreover, selection for high growth rate in GFP can be undertaken successfully before full market size has been reached. The outcome of this study was production of an improved culture strain of GFP for the Vietnamese culture industry that will be trialed in real farm production environments to confirm the genetic gains identified in the experimental stock improvement program.

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Bananas (Musa sp) are one of the most important food crops in the world and provide a staple food and source of income in many households especially in Africa. Diseases are a major constraint to production with bunchy top, caused by Banana bunchy top virus (BBTV) generally considered the most important virus disease of bananas worldwide. Of the fungal diseases, Fusarium wilt, caused by the Fusarium oxysporum f.sp cubense (Foc), and black Sigatoka, caused by Mycosphaerella fijiensis, are arguably two of the most important and cause significant yield losses. The low fertility of commercially important banana cultivars has hampered efforts to generate disease resistance using conventional breeding. Possible alternative strategies to generate or increase disease resistance are through genetic engineering or by manipulation of the innate plant defence mechanisms, namely systemic acquired resistance (SAR). The first research component of this thesis describes attempts to generate BBTV-resistant banana plants using a genetic modification approach. The second research component of the thesis focused on the identification of a potential marker gene associated with SAR in banana plants and a comparison of the expression levels of the marker gene in response to biotic and abiotic stresses, and chemical inducers. Previous research at QUT CTCB showed that replication of BBTV DNA components in banana embryogenic cell suspensions (ECS) was abolished following co-bombardment with 1.1mers of mutated BBTV DNA-R. BBTV DNA-R encodes the master replication protein (Rep) and is the only viral protein essential for BBTV replication. In this study, ECS of banana were stably transformed with the same constructs, each containing a different mutation in BBTV DNA-R, namely H41G, Y79F and K187M, to examine the effect on virus replication in stably transformed plants. Cells were also transformed with a construct containing a native BBTV Rep. A total of 16, 16, 11 and five lines of stably transformed banana plants containing the Y79F, H41G, K187M and native Rep constructs, respectively, were generated. Of these, up to nine replicates from Y79F lines, four H41G lines, seven K187M lines and three native Rep lines were inoculated with BBTV by exposure to viruliferous aphids in two separate experiments. At least one replicate from each of the nine Y79F lines developed typical bunchy top symptoms and all tested positive for BBTV using PCR. Of the four H41G lines tested, at least one replicate from three of the lines showed symptoms of bunchy top and tested positive using PCR. However, none of the five replicates of one H41G line (H41G-3) developed symptoms of bunchy top and none of the plants tested positive for BBTV using PCR. Of the seven K187M lines, at least one replicate of all lines except one (K187M-1) developed symptoms of bunchy top and tested positive for BBTV. Importantly, none of the four replicates of line K187M-1 showed symptoms or tested positive for BBTV. At least one replicate from each of the three native Rep lines developed symptoms and tested positive for BBTV. The H41G-3 and K187M-1 lines possibly represent the first transgenic banana plants generated using a mutated Rep strategy. The second research component of this thesis focused on the identification of SAR-associated genes in banana and their expression levels in response to biotic and abiotic stresses and chemical inducers. The impetus for this research was the observation that tissue-cultured (TC) banana plants were more susceptible to Fusarium wilt disease (and possibly bunchy top disease) than plants grown from field-derived suckers, possibly due to decreased levels of SAR gene expression in the former. In this study, the pathogenesis-related protein 1 (PR-1) gene was identified as a potential marker for SAR gene expression in banana. A quantitative real-time PCR assay was developed and optimised in order to determine the expression of PR-1, with polyubiquitin (Ubi-1) found to be the most suitable reference gene to enable relative quantification. The levels of PR-1 expression were subsequently compared in Lady Finger and Cavendish (cv. Williams) banana plants grown under three different environmental conditions, namely in the field, the glass house and in tissue-culture. PR-1 was shown to be expressed in both cultivars growing under different conditions. While PR-1 expression was highest in the field grown bananas and lowest in the TC bananas in Lady Finger cultivar, this was not the case in the Cavendish cultivar with glass house plants exhibiting the lowest PR-1 expression compared with tissue culture and field grown plants. The important outcomes of this work were the establishment of a qPCR-based assay to monitor PR-1 expression levels in banana and a preliminary assessment of the baseline PR-1 expression levels in two banana cultivars under three different growing conditions. After establishing the baseline PR-1 expression levels in Cavendish bananas, a study was done to determine whether PR-1 levels could be increased in these plants by exposure to known banana pathogens and non-pathogens, and a known chemical inducer of SAR. Cavendish banana plants were exposed to pathogenic Foc subtropical race 4 (FocSR4) and non-pathogenic Foc race 1 (Foc1), as well as two putative inducers of resistance, Fusarium lycopersici (Fol) and the chemical, acibenzolar-S-methyl (BION®). Tissue culture bananas were acclimatised under either glass house (TCS) or field (TCH) conditions and treatments were carried out in a randomised complete block design. PR-1 expression was determined using qPCR for both TCS and TCH samples for the period 12-72h post-exposure. Treatment of TCH plants using Foc1 and FocSR4 resulted in 120 and 80 times higher PR-1 expression than baseline levels, respectively. For TCS plants treated with Foc1, PR-1 expression was 30 times higher than baseline levels at 12h post-exposure, while TCS plants treated with FocSR4 showed the highest PR-1 expression (20 times higher than baseline levels) at 72h post-exposure. Interestingly, when TCS plants were treated with Fol there was a marked increase of PR-1 expression at 12 h and 48 h following treatment which was 4 and 8 times higher than the levels observed when TCS plants were treated with Foc1 and FocSR4, respectively. In contrast, when TCH plants were treated with Fol only a slight increase in PR-1 expression was observed at 12 h, which eventually returned to baseline levels. Exposure of both TCS and TCH plants to BION® resulted in no effect on PR-1 expression levels at any time-point. The major outcome of the SAR study was that the glass house acclimatised tissue culture bananas exhibited lower PR-1 gene expression compared to field acclimatised tissue culture plants and the identification of Fol as a good candidate for SAR induction in banana plants exhibiting low PR-1 levels. A number of outcomes that foster understanding of both pathogen-derived and plant innate resistance strategies in order to potentially improve banana resistance to diseases were explored in this study and include identification of potential inducers of systemic acquired resistance and a promising mutated Rep approach for BBTV resistance. The work presented in this thesis is the first report on the generation of potential BBTV resistant bananas using the mutated Rep approach. In addition, this is the first report on the status of SAR in banana grown under different conditions of exposure to the biotic and abiotic environment. Further, a robust qPCR assay for the study of gene expression using banana leaf samples was developed and a potential inducer of SAR in tissue culture bananas identified which could be harnessed to increase resistance in tissue culture bananas.