BIM competencies for delivering waste-efficient building projects in a circular economy

Competency measures are increasingly becoming effective ways for construction organizations to measure their ability to deliver waste-efficient projects. Despite the ongoing efforts in achieving the goals of the circular economy through BIM adoption, there is still a paucity of studies on building information modeling (BIM) competencies for delivering waste-efficient building projects. This paper, therefore, aims to identify and investigate critical BIM competencies for delivering waste-efficient building projects in a circular economy. The study adopts a pluralistic approach, using a combination of the review of extant literature, focus group discussions and questionnaire survey. Analysis of the focus group discussion along with the result of the literature review revealed forty-three preliminary BIM competencies, which were subjected to rigorous statistical analyses. Four broad categories of BIM competencies for delivering waste-efficient building projects emerged from the analyses. These are project management-related, construction-related, procurement-related, and design-related BIM competencies. Construction firms could use the BIM competencies identified in this study to enhance the delivery of waste-efficient building projects as well as assess their BIM competency requirements at an individual and organizational level

The effects of hyaluronan on the adipose-derived stem cell secretome for the treatment of osteoarthritis

Empirical thesis.Includes bibliographical references.Chapter 1. Adipose-derived mesenchymal stem cells & hyaluronan for the treatment of osteoarthritis : evidence for synergy? -- Chapter 2. Methods -- Chapter 3. Alterations in the secretome of clinically relevant preparations of adipose-derived mesenchymal stem cells co-cultured with hyaluronan -- Chapter 4. Priming adipose-derived mesenchymal stem cells with hyaluronan alters growth kinetics and increases attachment to articular cartilage -- Chapter 5. Hyaluronan-mediated stem cell secretions in osteoarthritis : a pilot study -- Chapter 6. Conclusions & future directions -- Chapter 7. Appendices.Osteoarthritis (OA) can be a debilitating degenerative disease and is the most common form of arthritic disease. There is a general consensus that current non-surgical therapies are insufficient for younger OA sufferers who are not candidates for knee arthroplasties. Adipose-derived mesenchymal stem cell (MSCs) therapy for the treatment of OA can slow disease progression and lead to neocartilage formation. Using Hyaluronan (HA) for delivery of MSC therapy in OA is widespread with no consideration of altered MSC function. The mechanism of action of MSCs is secretion driven. Therefore we sought to elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics and evaluate the effect on the MSC secretome. Using a range of clinically relevant preparations, a titration of hyaluronan concentrations, we assessed MSC adherence and proliferation on both culture plastic surfaces and a novel cartilage-adhesion assay. We employed an adherence time-course and dispersion imaging techniques to assess MSC binding to cartilage. Our data showed HA had profound dose-dependent effects on early growth kinetics and the secretome of MSCs at concentrations up to the hyaluronan entanglement point at 1 mg/mL. At higher concentrations viscosity effects outweighed any benefit of additional HA. The novel cartilage-adhesion assay revealed for the first time that HA-primed MSCs can increase cell attachment to cartilage and that the presence of HA did not.In conclusion, the investigation showed HA can have profound dose-dependent effects on MSCs. Although early data cytokine data suggested HA would negatively impact MSC mode of action, functional assessments of human osteoarthritic cartilage and synovium demonstrated HA culture modulated negative effects produce by the MSC secretome. Thus we have shown through exploration of the MSC secretome that MSCs cultured in HA would have a synergistic effect in MSC therapy for the treatment of knee OA.Mode of access: World wide web1 online resource (xviii, 349 pages) colour illustration

The effects of hyaluronan on the adipose-derived stem cell secretome for the treatment of osteoarthritis

Osteoarthritis (OA) can be a debilitating degenerative disease and is the most common form of arthritic disease. There is a general consensus that current non-surgical therapies are insufficient for younger OA sufferers who are not candidates for knee arthroplasties. Adipose-derived mesenchymal stem cell (MSCs) therapy for the treatment of OA can slow disease progression and lead to neocartilage formation. Using Hyaluronan (HA) for delivery of MSC therapy in OA is widespread with no consideration of altered MSC function. The mechanism of action of MSCs is secretion driven. Therefore we sought to elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics and evaluate the effect on the MSC secretome. Using a range of clinically relevant preparations, a titration of hyaluronan concentrations, we assessed MSC adherence and proliferation on both culture plastic surfaces and a novel cartilage-adhesion assay. We employed an adherence time-course and dispersion imaging techniques to assess MSC binding to cartilage. Our data showed HA had profound dose-dependent effects on early growth kinetics and the secretome of MSCs at concentrations up to the hyaluronan entanglement point at 1 mg/mL. At higher concentrations viscosity effects outweighed any benefit of additional HA. The novel cartilage-adhesion assay revealed for the first time that HA-primed MSCs can increase cell attachment to cartilage and that the presence of HA did not. In conclusion, the investigation showed HA can have profound dose-dependent effects on MSCs. Although early data cytokine data suggested HA would negatively impact MSC mode of action, functional assessments of human osteoarthritic cartilage and synovium demonstrated HA culture modulated negative effects produce by the MSC secretome. Thus we have shown through exploration of the MSC secretome that MSCs cultured in HA would have a synergistic effect in MSC therapy for the treatment of knee OA

Alterations in the Secretome of Clinically Relevant Preparations of Adipose-Derived Mesenchymal Stem Cells Cocultured with Hyaluronan

Osteoarthritis (OA) can be a debilitating degenerative disease and is the most common form of arthritic disease. There is a general consensus that current nonsurgical therapies are insufficient for younger OA sufferers who are not candidates for knee arthroplasties. Adipose-derived mesenchymal stem cells (MSCs) therapy for the treatment of OA can slow disease progression and lead to neocartilage formation. The mechanism of action is secretion driven. Current clinical preparations from adipose tissue for the treatment of OA include autologous stromal vascular fraction (SVF), SVF plus mature adipocytes, and culture-purified MSCs. Herein we have combined these human adipose-derived preparations with Hyaluronan (Hylan G-F 20: Synvisc) in vitro and measured alterations in cytokine profile. SVF plus mature adipocytes showed the greatest decreased in the proinflammatory cytokines IL-1β, IFN-γ, and VEGF. MCP-1 and MIP-1α decreased substantially in the SVF preparations but not the purified MSCs. The purified MSC preparation was the only one to show increase in MIF. Overall the SVF plus mature adipocytes preparation may be most suited of all the preparations for combination with HA for the treatment of OA, based on the alterations of heavily implicated cytokines in OA disease progression. This will require further validation using in vivo models

A Highly selective and sensitive ON-OFF-ON fluorescence chemosensor for cysteine detection in endoplasmic reticulum

A new complex between coumarin-based ligand (CL) and copper ion has been prepared and applied to be an ON-OFF-ON reversible fluorescence chemosensor for the detection of Cys with high sensitivity and specificity. In HEPES buffer, CL displayed high affinity towards Cu(²⁺) ion over other physiological and environmental metal ions, accompanied with a 98.4% of fluorescence quenching. In the presence of Cys, the detachment of Cu(²⁺) ion of CL-Cu(²⁺) ensemble led to the liberation of the fluorophore, CL, and thus fluorescence was recovered. The results of absorption and emission spectroscopy analyses confirmed that the fluorescence turn ON response of CL-Cu(²⁺) ensemble was selective towards Cys only with high sensitivity (detection of limit, 7.2×10(⁻⁷)M). Confocal microscopy studies indicated that the lipophilic CL targets the endoplasmic reticulum (ER) of live cells, where it could be functioned as a fluorescent chemosensor for visualization of Cys in this organelle. Quantitative fluorescence detection of Cys in ER was successfully realized by flow cytometry analysis. The developed chemosensor was further applied to detect Cys in real urine samples with great recoveries ranges from 95.41% to 107.40%.8 page(s

Establishing a reference range for oligodendroglioma classification using Higuchi dimension analysis

Gliomas are the most common type of brain tumours in adults and a significant cause of cancer-related mortality. The 1p/19q chromosome deleted oligodendroglioma subtype has been shown to have a good prognosis following chemotherapy. However the subjectivity inherent with associated tissue features in classifying this tumour has led to some uncertainty in diagnosis and identifying optimal treatment options. This study investigated the use of the Higuchi dimension (DH) as a diagnostic tool to differentiate between the oligodendrogliomas with and without loss of heterozygosity (LOH & noLOH respectively). Sixty-five neurosurgical resection specimens were analysed. DH was lower in the LOH tissue (mean±sd; 1.69±0.01; CI:1.69-1.71; p<0.05) compared to the non-deletion group (1.83±0.04; CI: 1.81-1.85; p<0.05). Our results indicate that oligodendroglioma tissue showed scale invariance and that the complexity of the tissue as determined by the Higuchi dimension decreased with loss of genetic heterozygosity. Determination of the fractal dimension of gliomas provides an inexpensive and accurate alternative for classification of oligodendrogliomas.4 page(s

Priming Adipose-Derived Mesenchymal Stem Cells with Hyaluronan Alters Growth Kinetics and Increases Attachment to Articular Cartilage

Background. Biological therapeutics such as adipose-derived mesenchymal stem cell (MSC) therapy are gaining acceptance for knee-osteoarthritis (OA) treatment. Reports of OA-patients show reductions in cartilage defects and regeneration of hyaline-like-cartilage with MSC-therapy. Suspending MSCs in hyaluronan commonly occurs in animals and humans, usually without supporting data. Objective. To elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics. Methods. Using a range of hyaluronan concentrations, we measured MSC adherence and proliferation on culture plastic surfaces and a novel cartilage-adhesion assay. We employed time-course and dispersion imaging to assess MSC binding to cartilage. Cytokine profiling was also conducted on the MSC-secretome. Results. Hyaluronan had dose-dependent effects on growth kinetics of MSCs at concentrations of entanglement point (1 mg/mL). At higher concentrations, viscosity effects outweighed benefits of additional hyaluronan. The cartilage-adhesion assay highlighted for the first time that hyaluronan-primed MSCs increased cell attachment to cartilage whilst the presence of hyaluronan did not. Our time-course suggested patients undergoing MSC-therapy for OA could benefit from joint-immobilisation for up to 8 hours. Hyaluronan also greatly affected dispersion of MSCs on cartilage. Conclusion. Our results should be considered in future trials with MSC-therapy using hyaluronan as a vehicle, for the treatment of OA

Economic Modeling of Compressed Air Energy Storage

Due to the variable nature of wind resources, the increasing penetration level of wind power will have a significant impact on the operation and planning of the electric power system. Energy storage systems are considered an effective way to compensate for the variability of wind generation. This paper presents a detailed production cost simulation model to evaluate the economic value of compressed air energy storage (CAES) in systems with large-scale wind power generation. The co-optimization of energy and ancillary services markets is implemented in order to analyze the impacts of CAES, not only on energy supply, but also on system operating reserves. Both hourly and 5-minute simulations are considered to capture the economic performance of CAES in the day-ahead (DA) and real-time (RT) markets. The generalized network flow formulation is used to model the characteristics of CAES in detail. The proposed model is applied on a modified IEEE 24-bus reliability test system. The numerical example shows that besides the economic benefits gained through energy arbitrage in the DA market, CAES can also generate significant profits by providing reserves, compensating for wind forecast errors and intra-hour fluctuation, and participating in the RT market

The impact of the Virtual Ophthalmology Clinic on medical students' learning : a randomised controlled trial

Aim: The Virtual Ophthalmology Clinic (VOC) is an interactive web-based teaching module, with special emphasis on history taking and clinical reasoning skills. The purpose of this study was to determine the impact of VOC on medical students' learning. Methods: A randomised controlled trial (RCT) was conducted with medical students from the University of Sydney (n=188) who were randomly assigned into either an experimental (n=93) or a control group (n=95). A pre-and post-test and student satisfaction questionnaire were administered. Twelve months later a follow-up test was conducted to determine the long-term retention rate of graduates. Results: There was a statistically significant (P<0.001) within-subject improvement pre-to post rotation in the number of correctly answered questions for both the control and experimental groups (mean improvement for control 10%, 95% CI 1.3-2.6, and for experimental 17.5%, 95% CI 3.0-4.0). The improvement was significantly greater in the experimental group (mean difference in improvement between groups 7.5%, 95% CI 0.8-2.3, P<0.001). At 12 months follow-up testing, the experimental group scored on average 1.6 (8%) (95%CI 0.4 to 2.7, P=0.007) higher than the controls. Conclusion: On the basis of a statistically significant improvement in academic performance and highly positive student feedback, the implementation of VOC may provide a means to address challenges to ophthalmic learning outcomes in an already crowded medical curriculum