1,625 research outputs found
Input shaping for PFC: how and why?
Predictive functional control (PFC) is a highly successful strategy within industry, but for cases with challenging dynamics the most effective tuning approaches are still an active research area. This paper shows how one can deploy some insights from the more traditional model predictive control literature in order to enable systematic tuning and in particular, to ensure that the key PFC tuning parameter, that is the desired closed-loop time constant, is effective. In addition to enabling easier and more effective tuning, the proposed approach has the advantage of being simple to code and thus retaining the simplicity of implementation and tuning that is a key selling point of PFC. This paper focuses on design for open-loop unstable and also processes with significant under-damping in their open-loop behaviour
Clover disease : Practical Findings and Recommendation for Control
Practical Findings and Recommendation for Control
During the past decade an infertility in ewes together with other breeding troubles and abnormalities of the sex organs of sheep became a serious problem in certain regions in Western Australia where pastures were composed predominantly of early (Dwalganup) subterranean clover
Working in partnership with vulnerable families: The experience of child and family health practitioners
Family circumstances in infancy are persistent and powerful determinants of children's physical and mental health, influencing inequalities that trace from childhood through to adulthood. While the social factors that perpetuate patterns of inequality are more complex than can be addressed through single interventions, child and family health (CFH) services represent crucial sites where trajectories of inequality can be disrupted. In particular, approaches that foster opportunities for practitionerparent engagement that challenge traditional hierarchical health care practice, such as the Family Partnership Model (FPM), are recommended as ways of addressing disadvantage. Little is known about how practitioners implement models of working in partnership with families and, consequently, there is a gap in understanding how best to develop and sustain these new CFH practices. This paper reports a research project that investigated the experiences of 25 health professionals working within a FPM framework with vulnerable families. Through discussion of four key themes redefining expertise, changing practices, establishing new relationships with parents and the complexities of partnership practice the paper offers first-hand accounts of reframing practices that recognise the needs, skills and expertise of parents and thus contribute to empowerment of families. © 2011 La Trobe University
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NET phase two local economic evaluation: report 2: impact evaluation findings: final report
The Effect of Water Deficits during Flowering and Seed Production on Cultivars of Subterranean Clover and Annual Medic
In improved pastures in inland southern Australia, the persistence and growth of annual pasture legumes depends in part on their ability to produce and conserve abundant seed for regeneration and production. For near-maximum seed production in spring, adequate soil water is needed for at least 70 days in subterranean clover (Trifolium subterraneum) and medic (Medicago) species. Water deficits during spring are a common occurrence, and they appear to be increasing in frequency. The effect of relatively short periods of water deficit during reproductive development has received some attention but the findings conflict. The present experiment was conducted to examine further the responses of subterranean clover to water deficits imposed during the reproductive phase, and to compare the response of medic to that of subterranean clover. The flowering of two early strains of subterranean clover (Northam, Daglish) was synchronised with two early-flowering cultivars of annual medic (Cyprus barrel medic and Harbinger strand medic). Seed production parameters were observed on four watering treatments (nil, early, mid and late deficits during the reproductive phase). Notable differences occurred between the two genera and between the water treatments in their effect on reproductive development. A highly significant interaction favouring medic was recorded between the legumes (clover, medic) and the early deficit treatment, in that the individual seed weight of medic was slightly enhanced by water stress and clover was significantly depressed. In the mid- and late-stress treatments, a significantly lower proportion of viable seed was recorded with clover versus medic. The implications of the findings for the use of adapted annual legumes are discussed. This research was supported by a Reserve Bank Research Fellowship
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Making the most of housing and growth in the East Midlands: a report on removing the barriers to low public investment in the region
The Smith Institute, in association with the Economic Strategy Research Bureau at Nottingham Business School, has undertaken an investigation into the lack of central government investment in the East Midlands in housing and physical regeneration. The work has been based on desk research, two round tables with stakeholders (in Nottingham and Melton Mowbray) and interviews with over 30 decision makers, experts and opinion formers from across the region. The objectives of the report were: first, to quantify the reduction in central government investment in the region compared with other regions; second, to suggest reasons why this might have
occurred; third, to consider the impact that this might be having on the implementation of government policies such as housing provision, ârebalancingâ the economy and achieving greater value for money for government investment. The report concludes with a number of recommendations for local enterprise partnerships
(LEPs), local authorities, the housing sector and central
government
Pasture legume varieties and ewe fertility
ALTHOUGH it was first thought that all varieties of subterranean clover would cause ewe infertility, research in the last 10 to 15 years has shown that varieties differ in potency.
The relative level of potency has also been shown to remain consistent for any one variety under normal conditions
The Feeding Practices and Structure Questionnaire: development and validation of age appropriate versions for infants and toddlers
Background
In order to measure and understand trajectories of parental feeding practices and their relationship with child eating and weight, it is desirable to perform assessment from infancy and across time, in age-appropriate ways. While many feeding practices questionnaires exist, none is presently available that enables tracking of feeding practices from infancy through childhood. The aim of the study was to develop a version of the Feeding Practices and Structure Questionnaire (FPSQ) for parents with infants and toddlers (<â2âyears) to be used in conjunction with the original FPSQ for older children (â„2âyears) to measure feeding practices related to non-responsiveness and structure across childhood.
Methods
Constructs and items for the FPSQ for infants and toddlers were derived from the existing and validated FPSQ for older children and supplemented by a review of the literature on infant feeding questionnaires. Following expert review, two versions of the questionnaire were developed, one for milk feeding parents and one for solid feeding parents. Data from two studies were combined (child ages 0â24âmonths) to test the derived constructs with Confirmatory Factor Analysis for the milk feeding (Nâ=â731) and solid feeding (Nâ=â611) versions.
Results
The milk feeding version consisted of four factors (18 items) and showed acceptable model fit and good internal reliability: âfeeding on demand vs. feeding routineâ (αâ=â0.87), âusing food to calmâ (αâ=â0.87), âpersuasive feedingâ (αâ=â0.71), âparent-led feedingâ (αâ=â0.79). The same four factors showed acceptable model fit for the solid feeding version (21 items), likewise with good internal reliability (αâ=â0.74, 0.86, 0.85, 0.84 respectively). Two additional factors (13 items) were developed for the solid feeding version that appeared developmentally appropriate only for children aged 12âmonths or older: âfamily meal environmentâ (αâ=â0.81) and âusing (non-)food rewardsâ (αâ=â0.92). The majority of factor-factor correlations were in line with those of the original FPSQ.
Conclusions
The FPSQ milk and solid feeding versions are the first measures specifically developed as precursors to the FPSQ to measure parental feeding practices in children <â2âyears, particularly practices related to non-responsiveness and structure. Further validation in more diverse samples is required
Molecular evolution of the hyaluronan synthase 2 gene in mammals: implications for adaptations to the subterranean niche and cancer resistance
The naked mole-rat (NMR) Heterocephalus glaber is a unique and fascinating mammal exhibiting many unusual adaptations to a subterranean lifestyle. The recent discovery of their resistance to cancer and exceptional longevity has opened up new and important avenues of research. Part of this resistance to cancer has been attributed to the fact that NMRs produce a modified form of hyaluronanâa key constituent of the extracellular matrixâthat is thought to confer increased elasticity of the skin as an adaptation for living in narrow tunnels. This so-called high molecular mass hyaluronan (HMM-HA) stems from two apparently unique substitutions in the hyaluronan synthase 2 enzyme (HAS2). To test whether other subterranean mammals with similar selection pressures also show molecular adaptation in their HAS2 gene, we sequenced the HAS2 gene for 11 subterranean mammals and closely related species, and combined these with data from 57 other mammals. Comparative screening revealed that one of the two putatively important HAS2 substitutions in the NMR predicted to have a significant effect on hyaluronan synthase function was uniquely shared by all African mole-rats. Interestingly, we also identified multiple other amino acid substitutions in key domains of the HAS2 molecule, although the biological consequences of these for hyaluronan synthesis remain to be determined. Despite these results, we found evidence of strong purifying selection acting on the HAS2 gene across all mammals, and the NMR remains unique in its particular HAS2 sequence. Our results indicate that more work is needed to determine whether the apparent cancer resistance seen in NMR is shared by other members of the African mole-rat clade.National Research Foundation (South Africa
Reliability and Physiological Interpretation of Pulmonary Gas Exchange by "Circulatory Equivalents" in Chronic Heart Failure
Peak ratios of pulmonary gas-exchange to ventilation during exercise (VËO2/VËE and VËCO2/VËE, termed "circulatory equivalents") are sensitive to heart failure (HF) severity, likely reflecting low and/or poorly distributed pulmonary perfusion. We tested whether peak VËO2/VËE and VËCO2/VËE would: (1) distinguish HF patients from controls; (2) be independent of incremental exercise protocol; and (3) correlate with lactate threshold (LT) and ventilatory compensation point (VCP), respectively.Twenty-four HF patients (61±11 years) with reduced ejection fraction (31±8%) and 11 controls (63±7 years) performed ramp-incremental cycle ergometry. Eighteen HF patients also performed slow (5±1 W/min), medium (9±4 W/min), and fast (19±6 W/min) ramps. Peak VËO2/VËE and VËCO2/VËE from X-Y plot, and LT and VCP from 9-panel plot, were determined by 2 independent, blinded, assessors. Peak VËO2/VËE (31.2±4.4 versus 41.8±4.8 mL/L; P<0.0001) and VËCO2/VËE (29.3±3.0 versus 36.9±4.0 mL/L; P<0.0001) were lower in HF than controls. Within individuals, there was no difference across 3 ramp rates in peak VËO2/VËE (P=0.62) or VËCO2/VËE (P=0.97). Coefficient of variation (CV) in peak VËO2/VËE was lower than for LT (5.1±2.1% versus 8.2±3.7%; P=0.014), and coefficient of variation in peak VËCO2/VËE was lower than for VCP (3.3±1.8% versus 8.7±4.2%; P<0.001). In all participants, peak VËO2/VËE was correlated with, but occurred earlier than, LT (r2=0.94; mean bias, -0.11 L/min), and peak VËCO2/VËE was correlated with, but occurred earlier than, VCP (r2=0.98; mean bias -0.08 L/min).Peak circulatory equivalents during exercise are strongly associated with (but not identical to) LT and VCP. Peak circulatory equivalents are reliable, objective, effort-independent indices of gas-exchange abnormality in HF
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