Properties of hand-made clay balls used as a novel filter media

Filtration using granular media such as quarried sand, anthracite and granular activated carbon is a well-known technique used in both water and wastewater treatment. A relatively new prefiltration method called pebble matrix filtration (PMF) technology has been proved effective in treating high turbidity water during heavy rain periods that occur in many parts of the world. Sand and pebbles are the principal filter media used in PMF laboratory and pilot field trials conducted in the UK, Papua New Guinea and Serbia. However during first full-scale trials at a water treatment plant in Sri Lanka in 2008, problems were encountered in sourcing the required uniform size and shape of pebbles due to cost, scarcity and Government regulations on pebble dredging. As an alternative to pebbles, hand-made clay pebbles (balls) were fired in a kiln and their performance evaluated for the sustainability of the PMF system. These clay balls within a filter bed are subjected to stresses due to self-weight and overburden, therefore, it is important that clay balls should be able to withstand these stresses in water saturated conditions. In this paper, experimentally determined physical properties including compression failure load (Uniaxial Compressive Strength) and tensile strength at failure (theoretical) of hand-made clay balls are described. Hand-made clay balls fired between the kiln temperatures of 875oC to 960oC gave failure loads of between 3.0 kN and 7.1 kN. In another test when clay balls were fired to 1250oC the failure load was 35.0 kN compared to natural Scottish cobbles with an average failure load of 29.5 kN. The uniaxial compressive strength of clay balls obtained by experiment has been presented in terms of the tensile yield stress of clay balls. Based on the effective stress principle in soil mechanics, a method for the estimation of maximum theoretical load on clay balls used as filter media is proposed and compared with experimental failure loads.

Are academics messy? Testing the broken windows theory with a field experiment in the work environment

We test the broken windows theory using a field experiment in a shared area of an academic workplace(the department common room). More specifically, we explore academics’ and postgraduate students’ behavior under an order condition (a clean environment) and a disorder condition (a messy environment). We find strong evidence that signs of disorderly behavior trigger littering: In 59% of the cases, subjects litter in the disorder treatment as compared to 18% in the order condition. These results remain robust in a multivariate analysis even when controlling for a large set of factors not directly examined by previous studies. Overall, when academic staff and postgraduate students observe that others have violated the social norm of keeping the common room clean, all else being equal, the probability of littering increases by around 40%.

Five commercial citrus rate poorly as hosts of the polyphagous fruit flyBactrocera tryoni(Froggatt) (Diptera: Tephritidae) in laboratory studies

Queensland fruit fly, Bactrocera tryoni (Froggatt), is a polyphagous pest, and many citrus types are included among its hosts. While quantification of citrus host use by B. tryoni is lacking, citrus is generally considered a ‘low pressure’ crop. This paper investigates B. tryoni female oviposition preference and offspring performance in five citrus types; Murcott mandarin (Citrus reticulata), Navel orange and Valencia orange (Citrus sinensis), Eureka lemon (Citrus limon) and yellow grapefruit (Citrus paradisi). Oviposition preference was investigated in laboratory-based choice and no-choice experiments, while immature survival and offspring performance were investigated by infesting fruits in the laboratory and evaluating pupal recovery, pupal emergence and F1 fecundity. Fruit size, Brix level and peel toughness were also measured for correlation with host use. Bactrocera tryoni demonstrated an oviposition preference hierarchy among the citrus fruits tested; Murcott and grapefruit were most preferred for oviposition and lemon the least, while preference for Navel and Valencia was intermediate. Peel toughness was negatively correlated with B. tryoni oviposition preference, while no significant correlations were detected between oviposition and Brix level or fruit size. Immature survival in the tested fruit was very low. Murcott was the best host (21% pupal recovery), while all other citrus types that showed pupal recovery of 6% or lower and no pupae were recovered from Valencia orange. In pupae recovered from Navel orange and lemon, adult eclosion was greatly reduced, while in grapefruit and lemon, no eggs were recovered from F1 adults. Based on these laboratory results, many commercial citrus varieties appear to be poor hosts for B. tryoni and may pose a low post-harvest and quarantine risk. These findings need to be confirmed in the field, as they impact on both pre-harvest and post-harvest countermeasures.

Utility of an alternative bicycle commute route of lower proximity to motorised traffic in decreasing exposure to ultra-fine particles, respiratory symptoms and airway inflammation - a structured exposure experiment

Background: Bicycle commuting in an urban environment of high air pollution is known as a potential health risk, especially for susceptible individuals. While risk management strategies aimed to reduce motorised traffic emissions exposure have been suggested, limited studies have assessed the utility of such strategies in real-world circumstances. Objectives: The potential of reducing exposure to ultrafine particles (UFP; < 0.1 µm) during bicycle commuting by lowering interaction with motorised traffic was investigated with real-time air pollution and acute inflammatory measurements in healthy individuals using their typical, and an alternative to their typical, bicycle commute route. Methods: Thirty-five healthy adults (mean ± SD: age = 39 ± 11 yr; 29% female) each completed two return trips of their typical route (HIGH) and a pre-determined altered route of lower interaction with motorised traffic (LOW; determined by the proportion of on-road cycle paths). Particle number concentration (PNC) and diameter (PD) were monitored in real-time in-commute. Acute inflammatory indices of respiratory symptom incidence, lung function and spontaneous sputum (for inflammatory cell analyses) were collected immediately pre-commute, and one and three hours post-commute. Results: LOW resulted in a significant reduction in mean PNC (1.91 x e4 ± 0.93 x e4 ppcc vs. 2.95 x e4 ± 1.50 x e4 ppcc; p ≤ 0.001). Besides incidence of in-commute offensive odour detection (42 vs. 56 %; p = 0.019), incidence of dust and soot observation (33 vs. 47 %; p = 0.038) and nasopharyngeal irritation (31 vs. 41 %; p = 0.007), acute inflammatory indices were not significantly associated to in-commute PNC, nor were these indices reduced with LOW compared to HIGH. Conclusions: Exposure to PNC, and the incidence of offensive odour and nasopharyngeal irritation, can be significantly reduced when utilising a strategy of lowering interaction with motorised traffic whilst bicycle commuting, which may bring important benefits for both healthy and susceptible individuals.

Laboratory and pilot scale pretreatment of sugarcane bagasse by acidified aqueous glycerol solutions

Pretreatment of sugarcane bagasse with acidified aqueous glycerol solution was evaluated at both laboratory and pilot scales. Laboratory scale pretreatment (4.00 g dry mass in 40.00 g liquid) with glycerol solutions containing ≤ 20 wt% water and 1.2 wt% HCl at 130 °C for 60 min resulted in biomass having glucan digestibilities of ≥ 88%. Comparable glucan enzymatic digestibility of 90% was achieved with bagasse pretreated at pilot scale (10 kg dry mass in 60 kg liquid) using a glycerol solution containing 0.4 wt% HCl and 17 wt% water at 130 °C for 15 min. We attribute more efficient pretreatment at pilot scale (despite shorter reaction time and reduced acid content) to improved mixing and heat transfer in a horizontal reactor. Pretreatment of sugarcane bagasse with acid-catalysed glycerol solutions likely produces glycerol-glycosides, which together with hydrolysed lignin are potential substrates for the production of biopolymers.

The emergence of emotions and religious sentiments during the September 11 disaster

Analyzing emotional states under duress or during heightened, life-and-death situations is extremely difficult, especially given the inability of laboratory experiments to replicate the environment and given the inherent biases of post event surveys. This is where natural experiments, such as the pager communications from September 11th can provide the kind of natural experiment emotion researchers have been seeking. We demonstrate that positive and pro-social communications are the first to emerge followed by the slower and lower negative communications. Religious sentiment is the last to emerge, as individual attempt to make sense of event. Additionally we provide a methodological discussion about the preparation and analysis of such natural experiments (the pager message content) and show the importance of using multiple methods to extract the broadest possible understanding.

Computer experiment – a case study for modelling and simulation of manufacturing systems

Deterministic computer simulation of physical experiments is now a common technique in science and engineering. Often, physical experiments are too time consuming, expensive or impossible to conduct. Complex computer models or codes, rather than physical experiments lead to the study of computer experiments, which are used to investigate many scientific phenomena. A computer experiment consists of a number of runs of the computer code with different input choices. The Design and Analysis of Computer Experiments is a rapidly growing technique in statistical experimental design. This paper aims to discuss some practical issues when designing a computer simulation and/or experiments for manufacturing systems. A case study approach is reviewed and presented.

The rural school experiment : creating a Queensland yeoman

Using historical narrative and extensive archival research, this thesis portrays the story of the twentieth century Queensland Rural Schools. The initiative started at Nambour Primary School in 1917, and extended over the next four decades to encompass thirty primary schools that functioned as centralized institutions training children in agricultural science, domestic science, and manual trade training. The Rural Schools formed the foundation of a systemised approach to agricultural education intended to facilitate the State’s closer settlement ideology. The purpose of the Rural Schools was to mitigate urbanisation, circumvent foreign incursion and increase Queensland’s productivity by turning boys into farmers, or the tradesmen required to support them, and girls into the homemakers that these farmers needed as wives and mothers for the next generation. Effectively Queensland took rural boys and girls and created a new yeomanry to aid the State’s development.

Nurse-administered procedural sedation and analgesia in the cardiac catheter laboratory : an integrative review

Objectives: To identify and appraise the literature concerning nurse-administered procedural sedation and analgesia in the cardiac catheter laboratory. Design and data sources: An integrative review method was chosen for this study. MEDLINE and CINAHL databases as well as The Cochrane Database of Systematic Reviews and the Joanna Briggs Institute were searched. Nineteen research articles and three clinical guidelines were identified. Results: The authors of each study reported nurse-administered sedation in the CCL is safe due to the low incidence of complications. However, a higher percentage of deeply sedated patients were reported to experience complications than moderately sedated patients. To confound this issue, one clinical guideline permits deep sedation without an anaesthetist present, while others recommend against it. All clinical guidelines recommend nurses are educated about sedation concepts. Other findings focus on pain and discomfort and the cost-savings of nurse-administered sedation, which are associated with forgoing anaesthetic services. Conclusions: Practice is varied due to limitations in the evidence and inconsistent clinical practice guidelines. Therefore, recommendations for research and practice have been made. Research topics include determining how and in which circumstances capnography can be used in the CCL, discerning the economic impact of sedation-related complications and developing a set of objectives for nursing education about sedation. For practice, if deep sedation is administered without an anaesthetist present, it is essential nurses are adequately trained and have access to vital equipment such as capnography to monitor ventilation because deeply sedated patients are more likely to experience complications related to sedation. These initiatives will go some way to ensuring patients receiving nurse-administered procedural sedation and analgesia for a procedure in the cardiac catheter laboratory are cared for using consistent, safe and evidence-based practices.

Issues and challenges associated with nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory : a qualitative study

Aims and objectives To explore issues and challenges associated with nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory from the perspectives of senior nurses. Background Nurses play an important part in managing sedation because the prescription is usually given verbally directly from the cardiologist who is performing the procedure and typically, an anaesthetist is not present. Design A qualitative exploratory design was employed. Methods Semi-structured interviews with 23 nurses from 16 cardiac catheterisation laboratories across four states in Australia and also New Zealand were conducted. Data analysis followed the guide developed by Braun and Clark to identify the main themes. Results Major themes emerged from analysis regarding the lack of access to anaesthetists, the limitations of sedative medications, the barriers to effective patient monitoring and the impact that the increasing complexity of procedures has on patients' sedation requirements. Conclusions The most critical issue identified in this study is that current guidelines, which are meant to apply regardless of the clinical setting, are not practical for the cardiac catheterisation laboratory due to a lack of access to anaesthetists. Furthermore, this study has demonstrated that nurses hold concerns about the legitimacy of their practice in situations when they are required to perform tasks outside of clinical practice guidelines. To address nurses' concerns, it is proposed that new guidelines could be developed, which address the unique circumstances in which sedation is used in the cardiac catheterisation laboratory. Relevance to clinical practice Nurses need to possess advanced knowledge and skills in monitoring for the adverse effects of sedation. Several challenges impact on nurses' ability to monitor patients during procedural sedation and analgesia. Preprocedural patient education about what to expect from sedation is essential.

Risk factors for impaired respiratory function during nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory : a matched case-control study

Background: Side effects of the medications used for procedural sedation and analgesia in the cardiac catheterisation laboratory are known to cause impaired respiratory function. Impaired respiratory function poses considerable risk to patient safety as it can lead to inadequate oxygenation. Having knowledge about the conditions that predict impaired respiratory function prior to the procedure would enable nurses to identify at-risk patients and selectively implement intensive respiratory monitoring. This would reduce the possibility of inadequate oxygenation occurring. Aim: To identify pre-procedure risk factors for impaired respiratory function during nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory. Design: Retrospective matched case–control. Methods: 21 cases of impaired respiratory function were identified and matched to 113 controls from a consecutive cohort of patients over 18 years of age. Conditional logistic regression was used to identify risk factors for impaired respiratory function. Results: With each additional indicator of acute illness, case patients were nearly two times more likely than their controls to experience impaired respiratory function (OR 1.78; 95% CI 1.19–2.67; p = 0.005). Indicators of acute illness included emergency admission, being transferred from a critical care unit for the procedure or requiring respiratory or haemodynamic support in the lead up to the procedure. Conclusion: Several factors that predict the likelihood of impaired respiratory function were identified. The results from this study could be used to inform prospective studies investigating the effectiveness of interventions for impaired respiratory function during nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory.

Toward an in-depth understanding of cardiovascular interventional nursing : a qualitative study into nursing within the cardiac catheterisation laboratory setting

Introduction: Nursing in the cardiac catheterisation laboratory (CCL) varies globally in terms of scope and deployment. In the US, all allied staff are cross-trained into all CCL roles. The Australian and New Zealand experience has legislative frameworks that reserves specific functions to nurses. Yet, the nursing role within the CCL is poorly researched and defined. Aim: This study sought to gain deeper understanding of the perceived role of CCL nurses in Australia and New Zealand. Method: A descriptive qualitative study using semi-structured in-depth interviews was used. A cross-sectional sample of 23 senior clinical nurses or nursing managers representing 16 CCLs across Australia and New Zealand was obtained. Data were digitally recorded and transcribed verbatim prior to analysis by three researchers. Results: Five major themes emerged from the data. These themes were: 1. The CCL is a unique environment; 2. CCL nursing is a unique and advanced cardiac nursing discipline; 3. The recruitment attributes for CCL nurses are advanced; 4. Education needs to be standardised; and 5. The evidence to support practice is poor. Discussion: The CCL environment is a dynamic, deeply interdisciplinary setting with CCL nursing seen to be a unique advanced practice role. Yet the time has come for a scope of practice, educational standards, guidelines and competencies was expressed by the participants. Conclusion: Nursing in the CCL is an advanced practice role working within a complex interdisciplinary environment. Further work is required to define the role of CCL nurses together with the evidence-base for their practice.

Australian and New Zealand nurses’ perceptions of procedural sedation and analgesia in the cardiac catheterisation laboratory : a qualitative study

Background: Australian and New Zealand College of Anaesthetists’ guidelines for procedural sedation and analgesia (PSA) are intended to apply across all clinical settings. As nurses are frequently responsible for patient care during PSA in the cardiac catheterisation laboratory (CCL), their perspectives can provide insight into the effectiveness of these guidelines within this particular setting. Methods: A cross-sectional sampling design was used to recruit nurses from urban, regional, public and private CCLs across Australia and New Zealand. Semi-structured interviews were conducted, digitally recorded and transcribed. Data were analysed using thematic analysis. Findings: Twenty-three nurses from 16 CCLs across four states in Australia and New Zealand participated. Most held senior positions (managers=14; educators=5) and CCL experience ranged from 4 to 26 years (mean 11). Participants were concerned about the legitimacy of their practice as they administered PSA outside of guideline recommendations and deemed present education and training as deficient. Participants noted also that guideline recommendations were sometimes not adhered to as it was difficult to balance the increasingly complex PSA requirements of their case-mix with limited access to anaesthetists while trying not to delay procedures. Conclusion: Findings suggest that application of current PSA guidelines may be impractical for CCL nurses and, as a consequence, they are often not followed. Participants were concerned about risks to patient safety as they felt education and training was not commensurable with practice requirements. The findings suggest existing guidelines should be reviewed or new guidelines developed which address nursing practice, education and competency standards for PSA in the CCL

Respiratory monitoring practices during procedural sedation and analgesia in the cardiac catheterisation laboratory could be improved by using capnography to assess ventilation

Background: Procedural sedation and analgesia (PSA) administered by nurses in the cardiac catheterisation laboratory (CCL) is unlikely to yield serious complications. However, the safety of this practice is dependent on timely identification and treatment of depressed respiratory function. Aim: Describe respiratory monitoring in the CCL. Methods: Retrospective medical record audit of adult patients who underwent a procedure in the CCLs of one private hospital in Brisbane during May and June 2010. An electronic database was used to identify subjects and an audit tool ensured data collection was standardised. Results: Nurses administered PSA during 172/473 (37%) procedures including coronary angiographies, percutaneous coronary interventions, electrophysiology studies, radiofrequency ablations, cardiac pacemakers, implantable cardioverter defibrillators, temporary pacing leads and peripheral vascular interventions. Oxygen saturations were recorded during 160/172 (23%) procedures, respiration rate was recorded during 17/172 (10%) procedures, use of oxygen supplementation was recorded during 40/172 (23%) procedures and 13/172 (7.5%; 95% CI=3.59–11.41%) patients experienced oxygen desaturation. Conclusion: Although oxygen saturation was routinely documented, nurses did not regularly record respiration observations. It is likely that surgical draping and the requirement to minimise radiation exposure interfered with nurses’ ability to observe respiration. Capnography could overcome these barriers to respiration assessment as its accurate measurement of exhaled carbon dioxide coupled with the easily interpretable waveform output it produces, which displays a breath-by-breath account of ventilation, enables identification of respiratory depression in real-time. Results of this audit emphasise the need to ascertain the clinical benefits associated with using capnography to assess ventilation during PSA in the CCL.