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Are patients with concussion getting optimal discharge advice at a regional emergency department?

- Brown, Ashlee, Twomey, Dara, Wong Shee, Anna

  • Authors: Brown, Ashlee , Twomey, Dara , Wong Shee, Anna
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Australian Journal of Rural Health Vol. 26, no. 2 (2018), p. 134-135
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  • Description: Mild traumatic brain injury (mTBI), known as concussion, is receiving increasing global attention. Growing concerns about the potential long-term effects of mTBI have highlighted the need for good management and follow- up care.1 Given that regional emergency departments (EDs) experience higher rates of mTBI presentations compared with metropolitan EDs and are often the first point of contact, the provision of evidence-based care in these settings is crucial for positive patient outcomes.2 Followup after mTBI has shown promising results in reducing the number and severity of symptoms.

Artificial neural network modeling and sensitivity analysis of performance and emissions in a compression ignition engine using biodiesel fuel

- Jaliliantabar, Farzad, Ghobadian, Barat, Najafi, Gholamhassan, Yusaf, Talal

  • Authors: Jaliliantabar, Farzad , Ghobadian, Barat , Najafi, Gholamhassan , Yusaf, Talal
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Energies Vol. 11, no. 9 (2018), p. 1-24
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  • Description: In the present research work, a neural network model has been developed to predict the exhaust emissions and performance of a compression ignition engine. The significance and novelty of the work, with respect to existing literature, is the application of sensitivity analysis and an artificial neural network (ANN) simultaneously in order to predict the engine parameters. The inputs of the model were engine load (0, 25, 50, 75 and 100%), engine speed (1700, 2100, 2500 and 2900 rpm) and the percent of biodiesel fuel derived from waste cooking oil in diesel fuel (B0, B5, B10, B15 and B20). The relationship between the input parameters and engine cylinder performance and emissions can be determined by the network. The global sensitivity analysis results show that all the investigated factors are effective on the created model and cannot be ignored. In addition, it is found that the most emissions decreased while using biodiesel fuel in the compression ignition engine.

Arylpyrrole and fipronil analogues that inhibit the motility and/or development of Haemonchus contortus in vitro

- Herath, Dilrukshi, Song, Hongjian, Preston, Sarah, Jabbar, Abdul, Wang, Tao, McGee, Sean, Hofmann, Andreas, Garcia-Bustos, Jose, Chang, Bill, Koehler, Anson, Liu, Yuxiu, Ma, Qiaoqiao, Zhang, Penqxiang, Zhao, Qiqi, Wang, Qingmin, Gasser, Robin

Assessing healthcare providers' performance with and without risk adjustment

- Morales-Silva, Daniel

  • Authors: Morales-Silva, Daniel
  • Date: 2018
  • Type: Text , Thesis , PhD
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  • Description: This study focuses on how healthcare data can be used to draw comparisons between healthcare providers (surgeons or hospitals). Depending on the type of access to datasets, these comparisons can be done with or without risk adjustment. For us, risk adjustment refers to the use of patient-level information to explain variation in healthcare spending, resource utilisation and health outcomes. For unadjusted comparisons, we highlight the diagnostic potential that radar plots offer for reporting on outcome indicators. These outcome indicators were obtained from hospital admissions of patients undergoing certain surgical procedures. We address two drawbacks of radar plots: presence of missing information and order of indicators. By introducing a consolidated view at provider level, we define an uncomplicated ranking of providers which can be used to identify potential low and high performers. For risk adjusted comparisons, we introduce a novel and robust methodology that enables comparisons of healthcare providers across multiple hierarchies, namely, surgeons, teams, departments and hospitals, using a consistent approach. Our methodology puts the patient at the centre of the analysis, and thus, can be used for personalised predictions (e.g. expected length of stay, costs and probability of being transferred to intensive care unit). Our findings suggest that the observed variation in selected outcome indicators, such as length of stay and charges of healthcare providers, cannot be explained by patient characteristics alone. Importantly, we have also observed that the perceived performance, on selected outcome indicators, of providers can change substantially following risk adjustment. Healthcare is unique in that clinical expertise is essential in guiding decision making and in informing all statistical models that seek to describe patient outcomes. For future iterations of our models, we will seek greater clinical input.
  • Description: Doctor of Philosophy

Assessing the spatial drivers of land use and land cover change in the protected and communal areas of the Zambezi Region, Namibia

- Kamwi, Jonathan, Cho, Moses, Kaetsch, Christoph, Manda, Samuel, Graz, Friedrich, Chirwa, Paxie

  • Authors: Kamwi, Jonathan , Cho, Moses , Kaetsch, Christoph , Manda, Samuel , Graz, Friedrich , Chirwa, Paxie
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Land Vol. 7, no. 4 (2018), p. 1-13
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  • Description: Understanding the patterns and drivers of land use and land cover (LULC) changes is fundamental for rational and specific planning for sustainable land management. Using remote sensing techniques, geographic information systems (GIS) and statistical modeling via multinomial logistic regression, we sought to identify spatial variables that determine LULC change and their extent over time in the protected and communal areas of the Zambezi Region, Namibia. Multi-temporal satellite imagery of the Landsat series was used to map changes over a period of twenty-six years, divided into three stages (1984-1991, 1991-2000 and 2000-2010). Post classification change detection methodologies were used to determine conversions between LULC classes. Additionally, socio-economic characteristics of the area were used to identify drivers of changes. Four spatial drivers of LULC change that we identified included the distance to the nearest road, distance to settlements, population density and fire return periods. Population density, distance to settlements and fire return period were significantly associated with conversion from crop/grass land to crop/grass land and forest land to crop/grass, forest land to bare land and forest land to forest land in the protected area. In communal areas, distance to the road was found to significantly influence conversion from crop/grass land to crop/grass land. The study concluded that the influence of these drivers is attributable to distinct political and agro-demographical differences during the study period. Policy makers and planners need to take these drivers into consideration together with their subsidiaries to respond and make sound decisions regarding undesirable changes in LULC.

Assessment of error sources in measurements of field pH : Effect of operator experience, test kit differences, and time-of-day

- Robinson, Nathan, Norng, Sorn, Rees, David, Benke, Kurt, Davey, Michelle

  • Authors: Robinson, Nathan , Norng, Sorn , Rees, David , Benke, Kurt , Davey, Michelle
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Communications in Soil Science and Plant Analysis Vol. 49, no. 3 (2018), p. 269-285
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  • Description: Various methods exist to measure soil pH, and while there is general agreement between the existing published laboratory and field-based methods, the latter are subject to uncertainties including test kit reliability, accuracy, precision, and environmental factors. The contribution of this study is to quantify three uncertainties that affect the conversion between field pH and laboratory pH measurements, namely operator experience, choice of test kit, and the time-of-day for measurement. Soil samples from western Victoria, representing the pH range 4.5–10.0, were used in a randomized complete block design with 10 assessors split into two groups representing experienced and inexperienced users. Statistical analysis of laboratory and field pH was based on using the Maximum Likelihood Functional Relationship (MLFR) to determine if there was any bias between the two methods. Significant differences were found between experienced and inexperienced users, and between test kits. © 2017 Taylor & Francis.

Assessment to develop students’ strategies and competence as learners

- Fletcher, Anna

  • Authors: Fletcher, Anna
  • Date: 2018
  • Type: Text , Book chapter
  • Relation: Evidence-based learning and teaching : A look into Australian classrooms Chapter 11 p. 123-137
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  • Description: Assessment has been called “the bridge between teaching and learning” (Wiliam, 2011, p. 50), which reflects this chapter’s exploration of how students’ use of learning strategies can be developed when they engage in Assessment as Learning (AaL). The chapter’s discussion of AaL as an evidence-based teaching and learning approach derives from a larger mixed-methods study (Fletcher, 2015), in which teachers and students from Years 2, 4 and 6 worked together on an AaL writing project. The term AaL refers to assessment that is designed to enable students to reflect on and monitor their own progress to inform their future learning goals.

Autumn food habits of the brown bear Ursus arctos in the Golestan National Park : A pilot study in Iran

- Soofi, Mahmood, Qashqaei, Ali, Aryal, Achyut, Coogan, Sean

  • Authors: Soofi, Mahmood , Qashqaei, Ali , Aryal, Achyut , Coogan, Sean
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Mammalia Vol. 82, no. 4 (2018), p. 338-342
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  • Description: Food consumed by brown bears in the Golestan National Park in Iran was analyzed during autumn 2011. We identified 22 food items in 61 scats, with the most important food items being hawthorn fruit, cherry plum fruit and chestnut-leaved oak hard mast, based on importance value (IV) estimates of 26.4%, 18.1% and 12.9%, respectively. The overall bear diet (percent digestible dry matter) was composed of 77.9% soft mast (i.e. fruit), 21.3% hard mast and small proportions of other vegetation (0.3%) or animal matter (0.4%). One anthropogenic food was identified (vine grape) and was of minor importance (IV=0.2%).

Avenue and Arch : Ballarat's commemoration. How are community attitudes to war and peace reflected in the civic management of the Avenue of Honour and the Arch of Victory?

- Roberts, Philip

  • Authors: Roberts, Philip
  • Date: 2018
  • Type: Text , Thesis , PhD
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  • Description: This thesis examines the importance of memory, commemoration, heritage and militarism in relation to Ballarat’s Avenue of Honour and Arch of Victory. Inspired by Ken Inglis and other historians who have analysed war commemoration, the thesis argues that, led by the Lucas clothing company, Ballarat civic leaders and community members commemorated the war service and sacrifice of local soldiers, airmen, sailors and nurses by planting the 22-kilometre Avenue during 1917–19 and by constructing the prominent Arch in 1920. Although Ballarat voted against conscription in 1916 and 1917 and was a ‘divided’ society, the Avenue and Arch were able to unite members of the local community. From the 1920s, through memory and mythology during the civic maintenance of the Avenue and Arch, Australian community attitudes to war and peace were reflected, and a determined effort was made to remember the service and sacrifice of military personnel for all Australian wars. Discussion of the need for peace remained in the background until recent years. Important influences on the civic management were the collective memory of the so-called Lucas Girls, a group of former female employees of the Lucas clothing company, and of the members of the Arch of Victory/Avenue of Honour Committee. Increasingly, the embracing of the Anzac legend and an emphasis on loss and grief was reflected in the civic management. By 2017 the Avenue and Arch were in pristine condition and, through the Garden of the Grieving Mother, had transformed to symbolise the importance of remembering the sacrifices and grief of war and the need for peace. The project was based on documentary research and oral history, using an examination of newspaper and other documentary accounts from 1917–2017, a study of Arch of Victory/Avenue of Honour Committee papers and conservation management plans, research of relevant books and articles, landscape fieldwork and interviews with 26 people.
  • Description: Doctor of Philosophy

Bangladesh HR professionals’ competencies: Impact on firm performance and moderating effects of organisation life cycle

- Prikshat, Verma, Biswas, Kumar, Nankervis, Alan, Hoque, Rakibul

  • Authors: Prikshat, Verma , Biswas, Kumar , Nankervis, Alan , Hoque, Rakibul
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Evidence-based HRM Vol. 6, no. 2 (2018), p. 203-220
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  • Description: Purpose: The purpose of this paper is to examine the HR roles of Bangladesh HR professionals in the public and private firms in Bangladesh using Human Resource Competency Study (HRCS) model (2016). The impact of identified HR competencies on firm performance and moderation of this relationship concerning different stages of organisation life cycle (OLC) is also explored. Design/methodology/approach: This quantitative study uses the HRCS model (RBL, 2015) as its underpinning analytical framework, and explores the impact of identified HR competencies on firm performance and analyses whether this relationship is moderated by different OLC stages. The sample for this study consisted of 202 HR professionals from both public and private organisations in Bangladesh. Findings: Results confirmed that all the nine competencies of HRCS model were demonstrated by the HR professionals in Bangladesh. The “credible activist” competency achieved the top ranking and “paradox navigator competency” recorded the lowest. Minor variation in terms of levels of competencies was observed in the context of private and public firms. HR competencies positively impacted the firm performance and only the maturity and growth stages of a firm’s life cycle moderated this relationship. Originality/value: There is a deficit of studies which have tested this relationship in terms of the moderating effects of OLC stages in the Asian developing country context. Focusing on this paucity of research concerning the transference of western human resource management models in developing economies and their resultant impact on firm performance, this is the first study set out to explore whether the most cited western HRCS model (RBL, 2015) is useful in understanding HR competencies in Bangladesh. © 2018, Emerald Publishing Limited.

Best approximate solutions of inconsistent linear inequality systems

- Goberna, Miguel, Hiriart-Urruty, Jean-Baptiste, López, Marco

Best practice data life cycle approaches for the life sciences

- Griffin, Philippa, Khadake, Jyoti, LeMay, Kate, Lewis, Suzanna, Orchard, Sandra, Pask, Andrew, Pope, Bernard, Roessner, Ute, Russell, Keith, Seemann, Torsten, Treloar, Andrew, Tyagi, Sonika, Christiansen, Jeffrey, Dayalan, Saravanan, Gladman, Simon, Hangartner, Sandra, Hayden, Helen, Ho, William, Keeble-Gagnère, Gabriel, Korhonen, Pasi, Neish, Peter, Prestes, Priscilla, Richardson, Mark, Watson-Haigh, Nathan, Wyres, Kelly, Young, Neil, Schneider, Maria

Biogeochemical responses to holocene catchment-lake dynamics in the Tasmanian World Heritage Area, Australia

- Mariani, Michela, Beck, Kristen, Fletcher, Michael-Shawn, Gell, Peter, Saunders, Krystyna, Gadd, Patricia, Chisari, Robert

  • Authors: Mariani, Michela , Beck, Kristen , Fletcher, Michael-Shawn , Gell, Peter , Saunders, Krystyna , Gadd, Patricia , Chisari, Robert
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Journal of Geophysical Research: Biogeosciences Vol. 123, no. 5 (2018), p. 1610-1624
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  • Description: Environmental changes such as climate, land use, and fire activity affect terrestrial and aquatic ecosystems at multiple scales of space and time. Due to the nature of the interactions between terrestrial and aquatic dynamics, an integrated study using multiple proxies is critical for a better understanding of climate- and fire-driven impacts on environmental change. Here we present a synthesis of biological and geochemical data (pollen, spores, diatoms, micro X-ray fluorescence scanning, CN content, and stable isotopes) from Dove Lake, Tasmania, allowing us to disentangle long-term terrestrial-aquatic dynamics through the last 12 kyear. We found that aquatic dynamics at Dove Lake are tightly linked to vegetation shifts dictated by regional hydroclimatic variability in western Tasmania. A major shift in the diatom composition was detected at ca. 6 ka, and it was likely mediated by changes in regional terrestrial vegetation, charcoal, and iron accumulation. High rainforest abundance prior ca. 6 ka is linked to increased terrestrially derived organic matter delivery into the lake, higher dystrophy, anoxic bottom conditions, and lower light penetration depths. The shift to a landscape with a higher proportion of sclerophyll species following the intensification of El Niño-Southern Oscillation since ca. 6 ka corresponds to a decline in terrestrial organic matter input into Dove Lake, lower dystrophy levels, higher oxygen availability, and higher light availability for algae and littoral macrophytes. This record provides new insights on terrestrial-aquatic dynamics that could contribute to the conservation management plans in the Tasmanian World Heritage Area and in temperate high-altitude dystrophic systems elsewhere.

Breast density classification for cancer detection using DCT-PCA feature extraction and classifier ensemble

- Haque, Md Sarwar, Hassan, Md Rafiul, BinMakhashen, Galal, Owaidh, Abdullah, Kamruzzaman, Joarder

Canonical dual finite element method for solving nonconvex mechanics and topology optimization

- Ali, Elaf

  • Authors: Ali, Elaf
  • Date: 2018
  • Type: Text , Thesis , PhD
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  • Description: Canonical duality theory (CDT) is a newly developed, potentially powerful methodological theory which can transfer general multi-scale nonconvex/discrete problems in Rn to a unified convex dual problem in continuous space Rm with m n and without a duality gap. The associated triality theory provides extremality criteria for both global and local optimal solutions, which can be used to develop powerful algorithms for solving general nonconvex variational problems. This thesis, first, presents a detailed study of large deformation problems in 2-D structural system. Based on the canonical duality theory, a canonical dual finite element method is applied to find a global minimization to the general nonconvex optimization problem using a new primal-dual semi-definite programming algorithm. Applications are illustrated by numerical examples with different structural designs and different external loads. Next, a new methodology and algorithm for solving post buckling problems of a large deformed elastic beam is investigated. The total potential energy of this beam is a nonconvex functional, which can be used to model both pre- and post-buckling phenomena. By using the canonical dual finite element method, a new primal-dual semi-definite programming algorithm is presented, which can be used to obtain all possible post-buckled solutions. In order to verify the triality theory, mixed meshes of different dual stress interpolation are applied to obtain the closed dimensions between discretized displacement and discretized stress. Applications are illustrated by several numerical examples with different boundary conditions. We find that the global minimum solution of the nonconvex potential leads to the unbuckled state, and both of these two solutions are numerically stable. However, the local minimum solution leads to an unstable buckled state, which is very sensitive to the external load, thickness of the beam, numerical precision, and the size of finite elements. Finally, a mathematically rigorous and computationally powerful method for solving 3-D topology optimization problems is demonstrated. This method is based on CDT developed by Gao in nonconvex mechanics and global optimization. It shows that the so-called NP-hard Knapsack problem in topology optimization can be solved deterministically in polynomial-time via a canonical penalty-duality (CPD) method to obtain precise global optimal 0-1 density distribution at each volume evolution. The relation between this CPD method and Gao's pure complementary energy principle is revealed for the first time. A CPD algorithm is proposed for 3-D topology optimization of linear elastic structures. Its novelty is demonstrated by benchmark problems. Results show that without using any artificial technique, the CPD method can provide mechanically sound optimal design, also it is much more powerful than the well-known BESO and SIMP methods. Finally, computational complexity and conceptual/mathematical mistakes in topology optimization modeling and popular methods are explicitly addressed.
  • Description: Doctor of Philosophy
  • Description: Canonical duality theory (CDT) is a newly developed, potentially powerful method- ological theory which can transfer general multi-scale nonconvex/discrete problems in Rn to a unified convex dual problem in continuous space Rm with m

Carbon negative platform chemicals from waste using enhanced geothermal systems

- Ghayur, Adeel, Verheyen, Vincent

Cardiac response to exercise in normal ageing : What can we learn from masters athletes?

- Beaumont, Alexander, Campbell, Amy, Grace, Fergal, Sculthorpe, Nicholas

  • Authors: Beaumont, Alexander , Campbell, Amy , Grace, Fergal , Sculthorpe, Nicholas
  • Date: 2018
  • Type: Text , Journal article , Review
  • Relation: Current Cardiology Reviews Vol. 14, no. 4 (2018), p. 245-253
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  • Description: Background: Ageing is associated with an inexorable decline in cardiac and vascular function, resulting in an increased risk of Cardiovascular Disease (CVD). Lifestyle factors such as exercise have emerged as a primary therapeutic target in the prevention of CVD, yet older individuals are frequently reported as being the least active, with few meeting the recommended physical activity guidelines. In contrast, well trained older individuals (Masters athletes) have superior functional capacity than their sedentary peers and are often comparable with young non-athletes. Therefore, the 'masters' athlete may be viewed as a unique non-pharmacological model which may allow researchers to disentangle the inexorable from the preventable and the magnitude of the unavoidable 'true' reduction in cardiac function due to ageing. Conclusion: This review examines evidence from studies which have compared cardiac structure and function in well trained older athletes, with age-matched controls but otherwise healthy. © 2018 Bentham Science Publishers.

Cardiomyocyte functional etiology in heart failure with preserved ejection fraction is distinctive - A new preclinical model

- Curl, Claire, Danes, Vennetia, Bell, James, Raaijmakers, Antonia, Ip, Wendy, Chandramouli, Chanchal, Harding, Tristan, Porrello, Enzo, Erickson, Jeffrey, Charchar, Fadi, Kompa, Andrew, Edgley, Amanda, Crossman, David, Soeller, Christian, Mellor, Kimberley, Kalman, Jonathan, Harrap, Stephen, Delbridge, Lea

  • Authors: Curl, Claire , Danes, Vennetia , Bell, James , Raaijmakers, Antonia , Ip, Wendy , Chandramouli, Chanchal , Harding, Tristan , Porrello, Enzo , Erickson, Jeffrey , Charchar, Fadi , Kompa, Andrew , Edgley, Amanda , Crossman, David , Soeller, Christian , Mellor, Kimberley , Kalman, Jonathan , Harrap, Stephen , Delbridge, Lea
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Journal of the American Heart Association Vol. 7, no. 11 (2018), p. 1-32
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  • Description: Background--Among the growing numbers of patients with heart failure, up to one half have heart failure with preserved ejection fraction (HFpEF). The lack of effective treatments for HFpEF is a substantial and escalating unmet clinical need-and the lack of HFpEF-specific animal models represents a major preclinical barrier in advancing understanding of HFpEF. As established treatments for heart failure with reduced ejection fraction (HFrEF) have proven ineffective for HFpEF, the contention that the intrinsic cardiomyocyte phenotype is distinct in these 2 conditions requires consideration. Our goal was to validate and characterize a new rodent model of HFpEF, undertaking longitudinal investigations to delineate the associated cardiac and cardiomyocyte pathophysiology. Methods and Results--The selectively inbred Hypertrophic Heart Rat (HHR) strain exhibits adult cardiac enlargement (without hypertension) and premature death (40% mortality at 50 weeks) compared to its control strain, the normal heart rat. Hypertrophy was characterized in vivo by maintained systolic parameters (ejection fraction at 85%-90% control) with marked diastolic dysfunction (increased E/E'). Surprisingly, HHR cardiomyocytes were hypercontractile, exhibiting high Ca

Caucasian and south Asian men show equivalent improvements in surrogate biomarkers of cardiovascular and metabolic health following 6-weeks of supervised resistance training

- Knox, Allan, Sculthorpe, Nicholas, Grace, Fergal

  • Authors: Knox, Allan , Sculthorpe, Nicholas , Grace, Fergal
  • Date: 2018
  • Type: Text , Journal article
  • Relation: F1000Research Vol. 7, no. (2018), p. 1-16
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  • Description: Background: The South Asian population have greater cardiovascular risk than their age-matched Caucasian counterparts, characterized by unfavorable biomarkers. South Asians may also be partially resistant to the pleiotropic benefits of physical activity on cardiovascular health. There is a current absence of studies that compare markers of cardio-metabolic health between Caucasians and South Asians employing resistance exercise. This study set out to compare the response in biomarkers of cardio-metabolic health in Caucasians and South Asians in response to resistance exercise. Methods: Caucasian (n=15, 25.5 ± 4.8 yrs) and South Asian (n=13, 25.4 ± 7.0 yrs) males completed a 6-week progressive resistance exercise protocol. Fasting blood glucose, insulin, and their product insulin resistance (HOMA-IR), triglycerides (TRIGS), low density lipoprotein (LDL), high density lipoprotein (HDL), total cholesterol (TC), vascular endothelial growth factor (VEGF), asymmetric dimythylarginine (ADMA), L-arginine (L-ARG) and C-reactive protein (CRP) were established at baseline and following resistance exercise. Results: There were significant improvements in fasting glucose, TC, LDL, HDL and VEGF in both groups following resistance exercise ( p<0.05, for all). No change was observed in insulin, HOMA-IR, TRIGS, ADMA, L-ARG following resistance exercise ( p>0.05, in both groups). CRP increased in the South Asian group ( p<0.05) but not the Caucasian group ( p>0.05) Conclusions: The cardio-metabolic response to resistance exercise is comparable in young Caucasian and South Asian males though inflammatory response to exercise may be prolonged in South Asians.

Characterization of limacon gas expanders with consideration to the dynamics of apex seals and inlet control valve

- Phung, Truong, Sultan, Ibrahim

  • Authors: Phung, Truong , Sultan, Ibrahim
  • Date: 2018
  • Type: Text , Journal article
  • Relation: Journal of Engineering for Gas Turbines and Power Vol. 140, no. 12 (2018), p. 1-11
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  • Description: Limacon machine, of which the relative motion between the rotor and housing follows the limacon curve, belongs to a class of rotary positive displacement machines. The profiles of rotors and housings of those machines can be constructed of either limacon or circular curves, hence the names: limacon-to-limacon, circolimacon, and limacon-to-circular machines. This paper presents the investigation into the thermodynamic performance of the limacon-to-circular machines with the presence of apex seals and inlet valve. This paper sets out by briefly introducing the limacon technology and the construction of the limacon-to-circular machine working volume. The mathematical descriptions of ports positions and areas have also been introduced. The paper then discusses the flow and phase composition of working fluid through the working chambers as well as how the fluid velocity is modeled and calculated. Then the seal dynamic model and response of inlet valve are presented followed by the machine thermodynamic model. A case study has also been presented to show the responses of seals and inlet valve during the machine operation.