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IFN-γ ELISpot in severe cutaneous adverse reactions to First-line Antituberculosis drugs in an HIV endemic setting
No full textSevere cutaneous adverse reactions related to first-line antituberculosis drugs are associated with high mortality and long-term morbidity. Oral sequential drug challenge, as a form of drug provocation testing, helps to salvage therapy by identifying culprit drugs but is associated with risk and is costly. IFN-γ enzyme-linked immune absorbent spot (ELISpot), an adjunctive in vitro diagnostic tool, may help to guide risk-stratification approaches. To determine the diagnostic accuracy of IFN-γ ELISpot against full-dose sequential drug challenge, we analyzed samples collected prospectively at multiple time points in 32 patients with first-line antituberculosis drug‒associated severe cutaneous adverse reaction (81% HIV infected, 25 with drug reaction with eosinophilia and systemic symptoms, and 7 with Stevens‒Johnson syndrome/toxic epidermal necrolysis). Sensitivity of IFN-γ ELISpot was 33% (4 of 12), 13% (1 of 8), 11% (1 of 9), and 0% (0 of 4) for rifampicin, isoniazid, pyrazinamide, and ethambutol, respectively (positivity threshold ≥50 spot forming units/million cells). Specificity was 100% for all the four drugs. Rifampicin IFN-γ ELISpot sensitivity increased to 58% (7 of 12) if a threshold of 20 spot forming units was used and to 75% (3 of 4) when restricted to samples <12 weeks after acute severe cutaneous adverse reaction event; specificity remained 100% for both. IFN-γ ELISpot offers adequate risk stratification of rifampicin severe cutaneous adverse reaction using acute samples and lowered threshold for positivity. Given the low sensitivity of IFN-γ ELISpot for other first-line antituberculosis drugs, additional optimization is needed to improve risk-stratification potential
Developing food waste biorefinery: Using optimized inclined thin layer pond to overcome constraints of microalgal biomass production on food waste digestate
Get PDFDiversion of food waste from landfill through anaerobic digestion is a sustainable form of energy production (biogas) and the waste effluent (digestate) can be utilised as nutrient supply for microalgae cultivation. However, digestate has very high nutrient concentrations and is highly turbid, making it difficult to utilize as a nutrient source with conventional microalgae cultivation systems. Here we compared the efficiencies of a conventional open raceway pond (ORWP) and an improved inclined thin layer photobioreactor (ITLP) for the utilization and treatment of food waste derived digestate by Chlorella sp. The ITLP improved on volumetric and areal productivities by 17 and 3 times over the ORWP, with values of 0.563 and 31.916 g m −2 day −1 respectively. Areal nutrient removal via microalgae biomass were 2359.759 ± 64.75 and 260.815 ± 7.16 mg m −2 day −1 for nitrogen and phosphorous respectively in the ITLP, which are 2.8 times higher than obtained in the ORWP. The ITLP’s superiority stems from its ability to support a much higher average biomass yield of 6.807 g L −1, which was 7 times higher than in the ORWP. Mean irradiance in-situ was higher in the ITLP, irradiance distribution and utilization by the culture in the ITLP was 44% more efficient than in the ORWP. Our results indicate that the ITLP is a far more productive system than conventional raceway ponds. This demonstrates that integration of ITLP microalgae cultivation using digestate has the potential to make digestate management yield net benefit in food waste biorefinery settings
Sustainability integration and control systems: Case studies from Sri Lanka
No full textThis thesis investigates how and why sustainability integration of Management Controls Systems (MCSs) varies in relation to companies’ strategic approaches to handling environmental and social issues. According to the extant literature, sustainability issues remain decoupled from MCSs used for strategic management purposes since academics and practitioners are more focused on developing individual sustainability controls for compliance and disclosure requirements. This study aims to close this research gap. In particular, this research investigates how the strategic approach to sustainability influences the integration of Sustainability Control Systems (SCSs) with regular MCSs. Further, by focusing on contingencies related to a developing country - in this case, Sri Lankan manufacturing companies, this research addresses the dearth of literature related to developing countries. The disparity in the contextual aspects of developed and developing countries lies in their socio-economic levels. This study is one of the few engagement-based multiple-case studies in a developing country context using in-depth semi-structured interviews to examine variations in sustainability integration.
Building on Gond et al.’s (2012) scholarly work, a theoretical framework relying on two dimensions is proposed: (i) the extent of control integration (strong to weak) and (ii) the level of control complexity (complex to simple) of SCSs and MCSs to explore their link to the strategic approach (proactive, accommodative, and reactive). Data was collected from five Sri Lankan manufacturing companies through semi-structured interviews with senior managers, documentary evidence, researcher’s observations, and publicly available data. The data were analysed using pattern analysis to attest to each company’s plausibility with the configurations proposed by the theoretical framework that adopted replication logic.
The study identifies four types of control configurations (complex-strong, complex-weak, simple-strong, and simple-weak) that explain each company’s strategic approach to sustainability. A company characterised by a proactive strategic approach integrates controls strongly while having complex attributes. In contrast, reactive companies do not have a similar impetus for integration as the SCSs remain decoupled from MCSs with simple control attributes. The accommodative approach explains the interim combination of simple-strong and complex-weak configurations.
The study also demonstrates how contextual factors in developing countries, like Sri Lanka, play a critical role in fostering or hindering the integration of sustainability into control systems and strategies. Contrary to the literature, the findings of this study show that when companies advocate sustainability initiatives primarily through management systems, SCSs remains peripheral with limited contribution to the strategy development process. Due to the legislative system’s inefficiencies and corruption in countries like Sri Lanka, the present study concludes that regulatory forces are not sufficient drivers for sustainability integration. Further, customer influence for integration varies on the internationalisation of the products’ value chain position. Supporting existing literature, the analysis also found that several contingency factors, such as environmental uncertainty, organisational structure, and size, explain the extent of complexity in MCSs and SCSs.
The main theoretical contribution of the study is the recommendation of a framework for designing control systems that fit the organisation’s contingencies while promoting sustainability within the strategy. As such, the insights and recommendations provided in this thesis have possible policy implications. The findings offer important empirical insights to senior managers, regulators, and stakeholders to understand the boundary conditions for designing the MCSs and SCSs that allow embedding sustainability in corporate strategy, especially for companies operating in similar contextual and cultural structures. Further, the findings of this thesis highlight the need for research in understanding the complexities of the integration process and provide avenues for future research
A psychological resilience briefing intervention for helicopter emergency medical service observers
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Helicopter emergency medical services (HEMS) observers may be at risk of negative psychological effects associated with exposure to traumatic events during shifts. This article describes a quality improvement project for HEMS observers at Essex & Herts Air Ambulance.
Methods
A psychological resilience briefing intervention (PRBi) was developed and delivered during induction training with 60 HEMS observers. The PRBi aimed to raise awareness of traumatic events that observers may experience and provided basic education on 5 domains, including likely forms of trauma exposure, possible psychological reactions, advice on coping strategies and supporting colleagues, and resources that they could use if required. The intervention was intended to bolster resilience and reduce posttraumatic stress disorder symptoms, and to encourage adaptive coping styles in observers.
Results
Observers learned from and valued the PRBi; statistically significant increases were observed in awareness of the 5 domains from pre- to post-delivery, and free-text responses cited a variety of benefits to the observers. There was no indication that the PRBi caused harm.
Conclusion
The PRBi has now been included in the routine induction of observers at Essex & Herts Air Ambulance and has the potential to be repurposed for use in other settings, including medical schools
Chinese students and the experience of International Doctoral Study in STEM: Using a Multi-World model to understand challenges and success
No full textThis volume examines the diversified and challenging experiences of Chinese international STEM doctoral students at Australian institutes of higher education, exploring how intersections between research, personal life, and social experiences can be negotiated to achieve academic success and personal transformation.
By drawing on a range of qualitative and longitudinal research methods, the book foregrounds student narratives and utilizes a novel three-dimensional multi-world framework as an effective approach for understanding student experiences in a holistic way. It integrates Chinese philosophical perspectives and theories in the fields of educational psychology, international education, and doctoral education to interpret the nuances, complexity, and particularities of the cross-cultural STEM PhD experience, highlighting the importance of the supervisor–mentee relationship and the role of students’ cultural, social, and philosophical values in supporting their successful completion of the PhD degree. The analysis thus provides new insights into the ways in which these experiences vary across students, and might apply in other national contexts, and to non-STEM student cohorts.
This book will be a valuable resource for researchers and academics engaged in cross-cultural education, the sociology of education, and international and comparative education. It will be of particular interest to those with a focus on international doctoral education and cultural Asian studies
Severe maternal morbidity following stillbirth in Western Australia 2000–2015: a population-based study
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There is scant literature about the management of stillbirth and the subsequent risk of severe maternal morbidity (SMM). We aimed to assess the risk of SMM associated with stillbirths compared with live births and whether this differed by the presence of maternal comorbidities.
Methods
In this retrospective cohort study, we used a population-based dataset of all stillbirths and live births ≥ 20 weeks’ gestation in Western Australia between 2000 and 2015. SMM was identified using a published Australian composite for use with routinely collected hospital morbidity data. Maternal comorbidities were identified in the Hospital Morbidity Data Collection or the Midwives Notification System using a modified Australian chronic disease composite. Multivariable Poisson regression was used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for factors associated with SMM in analyses stratified by the presence of maternal comorbidities. Singleton and multiple pregnancies were examined separately.
Results
This study included 458,639 singleton births (2319 stillbirths and 456,320 live births). The adjusted RRs for SMM among stillbirths were 2.30 (95% CI 1.77, 3.00) for those without comorbidities and 4.80 (95% CI 4.11, 5.59) (Interaction P value < 0.0001) for those with comorbidities compared to live births without and with comorbidities, respectively.
Conclusion
In Western Australia between 2000 and 2015, mothers of stillbirths both with and without any maternal comorbidities had an increased risk of SMM compared with live births. Further investigation into why women who have had a stillbirth without any existing conditions or pregnancy complications develop SMM is warranted
Chronic neuropsychiatric sequelae of SARS‐CoV‐2: Protocol and methods from the Alzheimer's Association Global Consortium
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Coronavirus disease 2019 (COVID-19) has caused >3.5 million deaths worldwide and affected >160 million people. At least twice as many have been infected but remained asymptomatic or minimally symptomatic. COVID-19 includes central nervous system manifestations mediated by inflammation and cerebrovascular, anoxic, and/or viral neurotoxicity mechanisms. More than one third of patients with COVID-19 develop neurologic problems during the acute phase of the illness, including loss of sense of smell or taste, seizures, and stroke. Damage or functional changes to the brain may result in chronic sequelae. The risk of incident cognitive and neuropsychiatric complications appears independent from the severity of the original pulmonary illness. It behooves the scientific and medical community to attempt to understand the molecular and/or systemic factors linking COVID-19 to neurologic illness, both short and long term.
Methods
This article describes what is known so far in terms of links among COVID-19, the brain, neurological symptoms, and Alzheimer's disease (AD) and related dementias. We focus on risk factors and possible molecular, inflammatory, and viral mechanisms underlying neurological injury. We also provide a comprehensive description of the Alzheimer's Association Consortium on Chronic Neuropsychiatric Sequelae of SARS-CoV-2 infection (CNS SC2) harmonized methodology to address these questions using a worldwide network of researchers and institutions.
Results
Successful harmonization of designs and methods was achieved through a consensus process initially fragmented by specific interest groups (epidemiology, clinical assessments, cognitive evaluation, biomarkers, and neuroimaging). Conclusions from subcommittees were presented to the whole group and discussed extensively. Presently data collection is ongoing at 19 sites in 12 countries representing Asia, Africa, the Americas, and Europe.
Discussion
The Alzheimer's Association Global Consortium harmonized methodology is proposed as a model to study long-term neurocognitive sequelae of SARS-CoV-2 infection
Science inquiry pedagogy in Western Australian upper primary and lower secondary classrooms
No full textFor over 50 years science inquiry has been positively associated with student achievement. Recently, the role of science inquiry as a means of effective science teaching has come under increased scrutiny after analyses of international large scale assessments found an overall negative association between science inquiry and student achievement. Unclear in the research is how teachers are enacting science inquiry in the standard classroom, as previous research was based on classroom interventions and student reports.
This mixed methods research describes upper primary and lower secondary teachers' science inquiry enactment in 56 science lessons using a two-dimensional model of science inquiry. The findings show primary teachers enacted more inquiry than secondary teachers, and used predominantly guided inquiry, while secondary teachers used mainly closed inquiry. Although primary and secondary teachers enacted all the essential features of science inquiry, students did not experience science inquiry in its entirety. Further, students' exposure to the nature of scientific knowledge was limited.
This research provides a contemporary and multifaceted account of how teachers enacted science inquiry in their science lessons. The findings can be used by educational researchers and policy-makers to make informed decisions when seeking to improve science education
Long term outdoor microalgal phycoremediation of anaerobically digested abattoir effluent
No full textSufficient and reliable long-term field data on the growth, productivity and nutrient removal rates of microalgal based wastewater treatment system is essential to validate its overall techno-economic feasibility. Here, we investigated the semi-continuous microalgal cultivation of Scenedesmus sp. in anaerobically digested abattoir effluent (ADAE) for 13 months in outdoor raceway ponds operated at 20 cm depth. This study was initiated with three different cultures consisting of 1) monocultures of Chlorella sp., 2) Scenedesmus sp., and 3) an equal mixed concentration of both microalgae species. However, after 15 weeks, Scenedesmus sp. was found to be the most dominant microalgae species in all the different cultures, even completely taking over the Chlorella sp. monoculture. Over the course of summer and early autumn, the average weekly biomass productivity of Scenedesmus sp. cultures was 12.5 ± 0.6 g m−2 d−1 which was 16% and 30% higher than productivities recorded in spring and winter, respectively. All available ammoniacal nitrogen (NH3–N) was found to be exhausted during each growth period with an average 33.6% nitrogen assimilation rate. The average rate of phosphate and COD (chemical oxygen demand) removals were 85.2% and 37.5% throughout the cultivation period. No significant differences were found in carbohydrate, lipid and protein content of Scenedesmus sp. during different seasons of the year. Over 53% increase in biomass productivity can be achieved if CO2 is added to control culture pH at pH 6.5. Here, we successfully demonstrated reliability of continuous long-term cultivation of microalgae in ADAE for simultaneous wastewater treatment and algal biomass production
Oxidative torrefaction of densified woody biomass: Performance, combustion kinetics and thermodynamics
No full textTorrefaction in partially oxidative atmospheres is a non-traditional approach to the thermal pre-treatment of biomass. Despite the potential benefits arising from this compared to traditional torrefaction undertaken under costly inert atmospheres, the literature lacks data on the combustion and kinetic analyses of densified biomass torrefied under partially oxidative conditions comparable to those of (reusing) combustion flue gases. This paper, therefore, investigates the effects of partially oxidative atmosphere on the chemical functionality, combustion kinetics and thermodynamics of densified (Australian) woody biomass. Torrefaction was conducted at 250, 275, 300 °C for 30min under both inert and partially oxidative atmosphere (O2: 5 vol%, N2 balance). The kinetic parameters were derived from iso-conversional method over the entire conversion range. Results show that solid biofuel torrefied under partially oxidative atmospheres has superior chemical functionality (e.g., less oxygenates and higher thermal stability), but comparable physical properties to inert atmospheres. In addition, improved thermodynamic features and lower combustion activation energy for partially oxidative torrefied biomass was observed. Overall, the results suggest that the use of partially oxidative atmospheres for torrefaction not only produce a high quality solid biofuel but can also improve process efficiency by using waste heat and flue gases from other combustion processes to thermally pre-treat biomass