Scanning electron microscopic study of microstructure of Gala apples during hot air drying

Microscopic changes occur in plant food materials during drying significantly influence the macroscopic properties and quality factors of the dried food materials. It is very critical to study microstructure to understand the underlying cellular mechanisms to improve performance of the food drying techniques. However, there is very limited research conducted on such microstructural changes of plant food material during drying. In this work, Gala apple parenchyma tissue samples were studied using a scanning electron microscope for gradual microstructural changes as affected by temperature, time and moisture content during hot air drying at two drying temperatures: 57 ℃ and 70 ℃. For fresh samples, the average cellular parameter values were; cell area: 20000 μm2, ferret diameter: 160 μm, perimeter: 600 μm, roundness: 0.76, elongation: 1.45 and compactness: 0.84. During drying, a higher degree of cell shrinkage was observed with cell wall warping and increase in intercellular space. However, no significant cell wall breakage was observed. The overall reduction of cell area, ferret diameter and perimeter were about 60%, 40% and 30%. The cell roundness and elongation showed overall increments of about 5% and the compactness remained unchanged. Throughout the drying cycle, cellular deformations were mainly influenced by the moisture content. During the initial and intermediate stages of drying, cellular deformations were also positively influenced by the drying temperature and the effect was reversed at the final stages of drying which provides clues for case hardening of the material.

Students with AD/HD-related behaviours : Saudi mainstream teachers' knowledge and attitude towards inclusion

This study investigated Saudi mainstream primary teachers' knowledge of AD/HD and their attitudes towards the inclusion of students with AD/HD-related behaviours. The study also explored the relationships among teachers' attitudes towards inclusion, knowledge of AD/HD, efficacy beliefs for teaching students with behavioural problems, and relevant background factors such as teacher age, training and experience, and class size. In the first phase of the study, more than 200 Saudi teachers completed a four-part self-report questionnaire while in the second, 8 teachers completed semi-structured interviews. Findings from both phases of the study indicated that although teachers' knowledge of AD/HD was somewhat limited, they generally held positive attitudes towards the inclusion of students with AD/HD-related behaviours in regular classrooms. Additional significant influences on teachers' attitudes included class size as well as teachers' training and self-efficacy beliefs.

Trade in 'Dirty Air' : carbon crime and the politics of pollution

‘Carbon trading fraudsters may have accounted for up to 90% of all market activity in some European countries, with criminals pocketing billions, mainly in Britain, France, Spain, Denmark and Holland, according to Europol and the European law enforcement agency.’ (Mason, 2009). ‘Carbon offset projects often result in land grabs, local environmental and social conflicts, as well as the repression of local communities and movements. The CDM approval process for projects allows little space for the voices of Indigenous Peoples and local communities – in fact, no project has ever been rejected on the grounds of rights violations, despite these being widespread’. (Carbon Trade Watch, 2013)

Defining expected cost for the air conditioning to avoid a price spike of electricity market under DSR model

This work presents a demand side response model (DSR) which assists small electricity consumers, through an aggregator, exposed to the market price to proactively mitigate price and peak impact on the electrical system. The proposed model allows consumers to manage air-conditioning when as a function of possible price spikes. The main contribution of this research is to demonstrate how consumers can minimise the total expected cost by optimising air-conditioning to account for occurrences of a price spike in the electricity market. This model investigates how pre-cooling method can be used to minimise energy costs when there is a substantial risk of an electricity price spike. The model was tested with Queensland electricity market data from the Australian Energy Market Operator and Brisbane temperature data from the Bureau of Statistics during hot days on weekdays in the period 2011 to 2012.

Prevention of surgical site infection in total joint arthroplasty : an international tertiary care center survery

Background Prevention strategies are critical to reduce infection rates in total joint arthroplasty (TJA), but evidence-based consensus guidelines on prevention of surgical site infection (SSI) remain heterogeneous and do not necessarily represent this particular patient population. Questions/Purposes What infection prevention measures are recommended by consensus evidence-based guidelines for prevention of periprosthetic joint infection? How do these recommendations compare to expert consensus on infection prevention strategies from orthopedic surgeons from the largest international tertiary referral centers for TJA? Patients and Methods A review of consensus guidelines was undertaken as described by Merollini et al. Four clinical guidelines met inclusion criteria: Centers for Disease Control and Prevention's, British Orthopedic Association, National Institute of Clinical Excellence's, and National Health and Medical Research Council's (NHMRC). Twenty-eight recommendations from these guidelines were used to create an evidence-based survey of infection prevention strategies that was administered to 28 orthopedic surgeons from members of the International Society of Orthopedic Centers. The results between existing consensus guidelines and expert opinion were then compared. Results Recommended strategies in the guidelines such as prophylactic antibiotics, preoperative skin preparation of patients and staff, and sterile surgical attire were considered critically or significantly important by the surveyed surgeons. Additional strategies such as ultraclean air/laminar flow, antibiotic cement, wound irrigation, and preoperative blood glucose control were also considered highly important by surveyed surgeons, but were not recommended or not uniformly addressed in existing guidelines on SSI prevention. Conclusion Current evidence-based guidelines are incomplete and evidence should be updated specifically to address patient needs undergoing TJA.

Much confusion about inclusion in Australia's largest education system

Over the last three decades, growing international recognition of the right of students with a disability to attend their local school has prompted change in the formation of education policies, schooling structures and pedagogical practice. Inclusion, as the movement has become known, has since been taken up and developed to different degrees in different regions and to differing degrees of success. Yet, despite sincere attempts to better include students with physical, sensory and intellectual disabilities, new and different forms of exclusion have arisen since the late 1990s; particularly for students with social, emotional and/or behavioural difficulties. In this lecture, Dr Linda Graham reports on findings from a three year ARC Discovery project to consider the impact of inclusion on the New South Wales government schooling sector, Australia’s largest education system.

Air navigation services in Australia and the United States : a comparative case study

The central document governing the global organization of Air Navigation Services (ANS) is the Convention on International Civil Aviation, commonly referred to as the “Chicago Convention,” whose original version was signed in that city in 1944. In the Convention, Contracting States agreed to ensure the minimum standards of ANS established by ICAO, a specialized United Nations agency created by the Convention. Emanating from obligations under the Chicago Convention, ANS has traditionally provided by departments of national governments. However, there is a widespread trend toward transferring delivery of ANS services outside of line departments of national governments to independent agencies or corporations. The Civil Air Navigation Services Organisation (CANSO), which is the trade association for independent ANS providers, currently counts approximately 60 members, and is steadily growing. However, whatever delivery mechanisms are chosen, national governments remain ultimately responsible for ensuring that adequate ANS services are available. The provision by governments of ANS reflects the responsibility of the state for safety, international relations, and indirectly, the macroeconomic benefits of ensuring a sound infrastructure for aviation. ANS is a “public good” and an “essential good” provided to all aircraft using a country’s airfields and airspace. However, ANS also represents a service that directly benefits only a limited number of users, notably aircraft owners and operators. The idea that the users of the system, rather than the taxpaying public, should incur the costs associated with ANS provision is inherent in the commercialization process. However, ICAO sets out broad principles for the establishment of user charges, which member states are expected to comply with. ICAO states that only distance flown and aircraft weights are acceptable parameters for use in a charging system. These two factors are considered to be easy to measure, bear a reasonable relationship to the value of service received, and do not discriminate due to factors such as where the flight originated or the nation of aircraft registration.

Inclusion of tapered tubes in enhancing the crash performance of automotive frontal structures

This paper treats the design and analysis of an energy absorbing system. Experimental tests were conducted on a prototype, and these tests were used to validate a finite element model of the system. The model was then used to analyze the response of the system under dynamic impact loading. The response was compared with that of a similar system consisting of straight circular tubes, empty and foam-filled conical tubes. Three types of such supplementary devices were included in the energy absorbing system to examine the crush behavior and energy absorption capacity when subjected to axial and oblique impact loadings. The findings were used to develop design guidelines and recommendations for the implementation of tapered tubes in energy absorbing systems. To this end, the system was conceptual in form such that it could be adopted for a variety of applications. Nevertheless, for convenience, the approach in this study is to treat the system as a demonstrator car bumper system used to absorb impact energy during minor frontal collisions.

Bisphenol A degradation enhanced by air bubbles via advanced oxidation using in situ generated ferrous ions from nano zero-valent iron/palygorskite composite materials

Novel nano zero-valent iron/palygorskite composite materials prepared by evaporative and centrifuge methods are tested for the degradation of bisphenol A in an aqueous medium. A systematic study is presented which showed that nano zero-valent iron material has little effect on bisphenol A degradation. When hydrogen peroxide was added to initiate the reaction, some percentage of bisphenol A removal (∼20%) was achieved; however, with the aid of air bubbles, the percentage removal can be significantly increased to ∼99%. Compared with pristine nano zero-valent iron and commercial iron powder, nano zero-valent iron/palygorskite composite materials have much higher reactivity towards bisphenol A and these materials are superior as they have little impact on the solution pH. However, for pristine nano zero-valent iron, it is difficult to maintain the reaction system at a favourable low pH which is a key factor in maintaining high bisphenol A removal. All materials were characterized by X-ray diffraction, scanning electron microscopy, elemental analysis, transmission electron microscopy and X-ray photoelectron spectroscopy. The optimum conditions were obtained based on a series of batch experiments. This study has extended the application of nano zero-valent iron/palygorskite composites as effective materials for the removal of phenolic compounds from the environment.

Investigation of air quality at Lithgow Correctional Centre

This project was conducted at Lithgow Correctional Centre (LCC), NSW, Australia. Air quality field measurements were conducted on two occasions (23-27 May 2012, and 3-8 December 2012), just before and six months after the introduction of smoke free buildings policies (28 May 2012) at the LCC, respectively. The main aims of this project were to: (1) investigate the indoor air quality; (2) quantify the level of exposure to environmental tobacco smoke (ETS); (3) identify the main indoor particle sources; (4) distinguish between PM2.5 / particle number from ETS, as opposed to other sources; and (5) provide recommendations for improving indoor air quality and/or minimising exposure at the LCC. The measurements were conducted in Unit 5.2A, Unit 5.2B, Unit 1.1 and Unit 3.1, together with personal exposure measurements, based on the following parameters: -Indoor and outdoor particle number (PN) concentration in the size range 0.005-3 µm -Indoor and outdoor PM2.5 particle mass concentration -Indoor and outdoor VOC concentrations -Personal particle number exposure levels (in the size range 0.01-0.3 µm) -Indoor and outdoor CO and CO2 concentrations, temperature and relative humidity In order to enhance the outcomes of this project, the indoor and outdoor particle number (PN) concentrations were measured by two additional instruments (CPC 3787) which were not listed in the original proposal.

The effect of very small air gaps on small field dosimetry

The purpose of this study was to investigate the effect of very small air gaps (less than 1 mm) on the dosimetry of small photon fields used for stereotactic treatments. Measurements were performed with optically stimulated luminescent dosimeters (OSLDs) for 6 MV photons on a Varian 21iX linear accelerator with a Brainlab lMLC attachment for square field sizes down to 6 mm 9 6 mm. Monte Carlo simulations were performed using EGSnrc C++ user code cavity. It was found that the Monte Carlo model used in this study accurately simulated the OSLD measurements on the linear accelerator. For the 6 mm field size, the 0.5 mm air gap upstream to the active area of the OSLD caused a 5.3 % dose reduction relative to a Monte Carlo simulation with no air gap...

Partitioning of dioxins (PCDDs/Fs) in ambient air at urban residential locations

In this work, 17-polychlorinated dibenzo-pdioxin/furan (PCDD/Fs) isomers were measured in ambient air at four urban sites in Seoul, Korea (from February to June 2009). The concentrations of their summed values RPCDD/Fs) across all four sites ranged from 1,947 (271 WHO05 TEQ) (Jong Ro) to 2,600 (349 WHO05 TEQ) fg/m3 (Yang Jae) with a mean of 2,125 ± 317) fg/m3 (292 WHO05 TEQ fg/m3). The sum values for the two isomer groups of RPCDD and RPCDF were 527 (30 WHO05 TEQ) and 1,598 (263 WHO05 TEQ) fg/m3, respectively. The concentration profile of individual species was dominated by the 2,3,4,7,8-PeCDF isomer, which contributed approximately 36 % of the RPCDD/Fs value. The observed temporal trends in PCDD/F concentrations were characterized by relative enhancement in the winter and spring. The relative contribution of different sources, when assessed by principal component analysis, is explained by the dominance of vehicular emissions along with coal (or gas) burning as the key source of ambient PCDD/Fs in the residential areas studied.

Agent-based modelling simulation case study : assessment of airport check-in and evacuation process by considering group travel behaviour of air passengers

Passenger experience has become a major factor that influences the success of an airport. In this context, passenger flow simulation has been used in designing and managing airports. However, most passenger flow simulations failed to consider the group dynamics when developing passenger flow models. In this paper, an agent-based model is presented to simulate passenger behaviour at the airport check-in and evacuation process. The simulation results show that the passenger behaviour can have significant influences on the performance and utilisation of services in airport terminals. The model was created using AnyLogic software and its parameters were initialised using recent research data published in the literature.

Neoliberal social inclusion? The agenda of the Australian Universities Community Engagement Alliance

University–community engagement (UCE) represents a hybrid discourse and a set of practices within contemporary higher education. As a modality of research and teaching, ‘engagement’ denotes the process of universities forming partnerships with external communities for the promised generation of mutually beneficial and socially responsive knowledge, leading to enhanced economic, social and cultural developments. A critical discourse analysis (Fairclough 2003. Analysing Discourse: Textual analysis for social research. London: Routledge) of the Australian Universities Community Engagement Alliance’s (AUCEA) ‘Position Paper’(2008 Universities and community engagement (Position paper 2008–2010)), as reported in this article, suggests that its uneasy synthesis of neoliberal, social inclusion and civic engagement discourses into a hybrid UCE discourse semantically privileges neoliberal forms of engagement. Perhaps, as a result, the AUCEA seems to have missed an opportunity to influence the Australian ‘widening participation’ debate on securing access and opportunity for marginalised students at universities and building social and cultural capital within their communities of origin.