Description:
For risk analysis of reclaimed water, current animal and toxicity testing may not detect subtle effects such as interactions that could contribute to complex diseases such as cancers that develop over a long period of time. There is a need for assays that can be validated against known human physiological processes. We have previously validated sensitive human cell culture assays for their responsiveness to agents that induce carcinogenesis in vivo. In this initial study we analysed the effects of three batches of reclaimed water on human colonic cells. At concentrations of up to 10-fold, they had no significant effect on the cellular markers, indicating an overall lack of biological activity. The assay has potential but needs to be refined to maximise its sensitivity.
Description:
Aim To explore the prevalence of unmet demand for training by mature age Australians and to identify the main barriers to accessing training. Methods A total of 3007 Australians aged 45-74 years were surveyed using Computer Assisted Telephone Interviewing. The sample frame was randomly selected and stratified based on the capital city and the rest of the state, and data were weighted to be nationally representative. Results Over one-third (37%) of respondents who had worked in the past five years reported wanting to attend some form of training but were unable to; these were most likely women and those aged 45-54 year. Commonly cited reasons for not being able to attend training included not being able to fit it in with work commitments, affordability and employer reluctance. Conclusion Reduction of these barriers to workplace training can improve mature age people's ability to remain engaged in the workforce.
Description:
We study a special case of an optimal control problem governed by a differential equation and a differential rate{independent variational inequality, both with given initial conditions. Under certain conditions, the variational inequality can be reformulated as a differential inclusion with discontinuous right-hand side. This inclusion is known as sweeping process. We perform a discretization scheme and prove the convergence of optimal solutions of the discretized problems to the optimal solution of the original problem. For the discretized problems we study the properties of the solution map and compute its coderivative. Employing an appropriate chain rule, this enables us to compute the subdifferential of the objective function and to apply a suitable optimization technique to solve the discretized problems. The investigated problem is used to model a situation arising in the area of queuing theory.
Description:
Accurate and efficient identification of bat (Microchiroptera) echolocation calls has been hampered by poor knowledge of the intraspecific variability in calls (including regional variation), a lack of call parameters for use in separating species and the amount of time required to manually identify individual calls or call sequences We constructed and tested automated bat call identification keys for three regions in New South Wales, Australia, using over 4,000 reference calls in approximate to 300 call sequences per region. We used the program AnaScheme to extract time, frequency and shape parameters from calls recorded with the Anabat system Classification trees were built to separate species using these parameters and provided the decision rules for construction of the keys An 'Unknown' category was included in the keys for sequences that could not be confidently identified to species The reliability of the keys was tested automatically with AnaScheme, using independent ! sets of reference call sequences, and keys were refined before further testing on additional test sequences Regional keys contained 18-19 species or included species groups We report rates of sequence misidentification (accuracy) and correct identification (detection) relative to all sequences (including 'unknowns') used to test each version of a key. Refined versions of the keys were accurate, with total misidentification rates of 0 5-5 3% for the three regions Additionally, total correct identifications for regions were 56-75% (>= 50% for most species), an overall high rate of detection. When 'unknowns' were ignored, as is common in many published studies, correct identification for regions increased to 91-99%, rates which compare favourably to the most successful classifiers tested to date The future use of AnaScheme for automated bat call identification is promising, especially for the large-scale temporal and spatial acoustic sampling to which Anabat is particularly suited.
Description:
The Big Strike of 1919-20 was Broken Hill’s greatest industrial battle but the photographic record of this militant era on the Barrier mines is dominated by pictures of the Great 1909 Lockout. Rather than cover the details of these well-known disputes, this article considers the value and power of photographs of the disputes – their presence, absence, production and presentation in major newspapers and in postcards – an area which has secured far less attention from Australian labour historians. Our concern is not only to read this visual material as evidence of industrial disputes but also to consider how the widespread circulation of such images affected contemporary perceptions of The Hill. We argue that images of a militant locality with a determined labour movement, popular after the 1909 dispute, may well have attracted militant organisers to the town who were important players in the major 1919-20 Big Strike. These images have dominated perceptions of Broken Hill as a bastion of unionism ever since
Description:
This special issue of Critical Horizons takes up the problematic of political imaginaries from various angles. In putting political imaginaries into question, the conditions of possibility for “the political” (le politique) and “politics” (la politique) are interrogated, as well as the concrete, contemporary contexts in which they are embedded, and which they, in turn, transform. In light of the ongoing Global Financial Crisis, the continued ecological devastation of the earth, new sites of terrorism (such as Norway), but also the recent upsurge of protest movements around the world (from the socalled Arab Spring, to the Occupy movement), the questioning of existing horizons of political imaginaries are evident and, consequently, call for elucidation. The present special issue begins to articulate a field of responses to this urgent task.
Description:
A stickiness testing device based on the probe tack test has been designed and tested. It was used to perform in situ characterization of drying hemispherical drops with an initial radius 3.5 mm. Tests were carried out in two drying temperatures, 63 and 95 degreesC. Moisture and temperature histories of the drying drops of fructose, honey, sucrose, maltodextrin and sucrose-maltodextrin mixtures were determined. The rates of moisture evaporation of the fructose solution was the fastest while those of the maltodextrin solution was the lowest. A profile reversal was observed when the temperature profiles of these materials were compared. Different modes of failure were observed during the stickiness tests. Pure fructose and honey solutions remained completely sticky and failed cohesively until the end of drying. Pure sucrose solution remained sticky and failed cohesively until complete crystallization occurred. The surface of the maltodextrin drops formed a skin shortly after the start of drying. It exhibited adhesive failure and reached a state of non-adhesion. Addition of maltodextrin significantly altered the stickiness of sucrose solution. (C) 2002 Elsevier Science Ltd. All rights reserved.
Description:
A probe tack test has been used for the in situ characterization of the surface stickiness of hemispherical drops with an initial radius of 3.5 mm while drying. Surface stickiness of drops of fructose and maltodextrin solutions dried at 63degreesC and 95degreesC was determined. The effect of addition of maltodextrin on fructose solution-was studied with fructose/maltodextrin solid mass ratios of 4: 1, 1: 1, and 1:4. Pure fructose solutions remained completely sticky and failed cohesively even when their moisture approached zero. Shortly after the start of drying, the surface of the maltodextrin drops formed a skin, which rapidly grew in thickness. Subsequently the drop surface became completely nonsticky probably due to transformation of outer layers into a glassy material. Addition of malto,dextrin significantly altered the surface stickiness of drops of fructose solutions, demonstrating its use as an effective drying aid.
Description:
We report the synergistic and competitive interactions between multiple plasticizers in plasticized low-amylose starch that result in either enhanced or reduced water migration fluxes and effective moisture diffusivities. The starch was plasticized using glycerol and xylitol either individually or in 1:1 combination. The water migration fluxes and moisture diffusivities were higher in xylitol plasticized films compared to the glycerol plasticized ones. For low plasticizer concentrations, the presence of both the plasticizers competitively reduced the effective moisture diffusivities and moisture migration fluxes due to antiplasticization. However, at higher plasticizer contents (at and above 15wt%), the presence of multiple plasticizers enhanced the moisture migration fluxes and effective moisture diffusivities due to synergistic plasticization. The moisture migration fluxes and effective moisture diffusivities exhibited both moisture and plasticizer concentration dependence and the former was found to be stronger than the latter. These findings can be used for designing and controlling the vapor barrier properties of starch-based bioplastics during drying and formulation phase.
Description:
Solutions of fructose, maltodextrin (DE 5), and their mixtures at the ratios of 20:80, 40:60, 50:50, 60:40, and 80:20 were gelled with 1% agar-agar and dried under convective-conductive drying conditions. The thin slabs were maintained at isothermal drying condition of 30 and 50 degrees C. Yamamoto's simplified method based on regular regime approach was used to calculate the (effective) moisture diffusivity. Both the drying rates and the moisture diffusivity exhibited strong concentration dependence. The concentration dependence was stronger in the case of fructose and fructose rich solutions. Both the moisture diffusivity and drying rates of the mixture solutions were enhanced due to plasticization of fructose on maltodextrin, which is explained through free volume theory.
Description:
Stickiness of whey protein isolate (WPI) and spray dried lactose droplets was studied at two air temperatures (65±0.5°C, 80±0.5°C), 0.75 m/s air velocity and 2-2.5% relative humidity using an in situ stickiness testing device. A stainless steel probe with 50 mm/min contact/withdrawal speed was used. The moisture and temperature histories were measured through parallel experiments. In each case, the surface of the lactose droplet remained sticky and failed cohesively until the surface was completely surrounded with crystals. The crystal layer remained fragile, fractured upon the probe contact and a thin layer of solution came out to the probe surface even after the moisture (u, dry basis) was lower than 0.2. WPI droplets formed thin and smooth skin immediately after coming in contact with hot air. The tensile strength of this skin increased rapidly and peaked (u = 2.14 at 45°C and u = 1. 47 at 65.7°C) fairly early during drying process. WPI droplet surface became completely non-sticky soon after attaining the peak tensile strength (u =1.32 at 53.4 °C and u= 1.05 at 68.8°C), mainly due to transformation of the outer layer of the skin into glassy material. The skin forming and surface active nature of WPI was exploited to minimize the stickiness of honey during spray drying. Replacement of 5% (w/w) maltodextrin with WPI raised the powder recovery of honey solids from 28% to 80%. Stickiness of the WPI on glass, Teflon and polyurethane surfaces was studied by replacing the contact surface of the probe with these materials. It was found that the stickiness of glass surface was the highest at test temperatures. Teflon surface offered the lowest stickiness at the test temperatures making it suitable materials to minimize solution/particle stickiness through coating.
Description:
Drying kinetics of low molecular weight sugars such as fructose, glucose, sucrose and organic acid such as citric acid and high molecular weight carbohydrate such as maltodextrin (DE 6) were determined experimentally using single drop drying experiments as well as predicted numerically by solving the mass and heat transfer equations. The predicted moisture and temperature histories agreed with the experimental ones within 6% average relative (absolute) error and average difference of +/- 1degreesC, respectively. The stickiness histories of these drops were determined experimentally and predicted numerically based on the glass transition temperature (T-g) of surface layer. The model predicted the experimental observations with good accuracy. A nonsticky regime for these materials during spray drying is proposed by simulating a drop, initially 120 mum in diameter, in a spray drying environment.
Description:
The change in textural attributes (hardness, chewiness and rate of softening) of three potato cultivars (Russet Burbank, Desiree and Sebago) was investigated. Uniform cylindrical samples (35-mm diameter and 3-mm thick) were prepared and exposed to different thermal processing regimes including; heating at 85°C, 95°C in water and steaming (100.2°C). The effect of salt on these textural attributes was also investigated using different salt concentrations (1.5%, 3% and 6% (w/w) NaCl). After thermal treatments the samples were subjected to texture profile analysis. The instrumental textural attributes were greatly affected by the cultivars and the thermal processing regimes. The change in textural attributes upon steaming was only marginally different compared to that at 95°C in water. Low concentrations of salt (1-3%) were found to accelerate the softening of the texture in these cultivars especially at lower temperatures. The textural attributes were modelled using a two-parameter reaction kinetics model. There was reasonable agreement by the model findings on the textural attributes prepared from all the thermal processing regimes and in presence and absence of (within average absolute error of 1.9-7%). Further, the model indicated that the order of reaction varied from 1.15-2.18 indicating that the changes in textural attributes in these thermal processing regimes followed higher reaction orders. [ABSTRACT FROM AUTHOR]
Description:
The idea of publishing a special issue on proteins and enzymes was conceived during the 18th International Drying Symposium (IDS2012) held in the historical city of Xiamen, China (November 11-15, 2012). It appeared to us that a number of scientists and engineers were enthusiastically undertaking research in various aspects of drying of proteins and enzymes. Professors Arun Mujumdar and Sakamon Devhastin encouraged me to explore the possibility of bringing at least one special issue that would depict contemporary research undertakings in the broader theme involving proteins and enzymes. We were somewhat unsure in the beginning whether or not the required number of high quality mansucripts could be garnered for one issue in the time constraint we had in mind. Editorial
Description:
This paper provides a comprehensive measurement study on three video streaming websites with social media features - ‘TED Talks’, ‘xHamster’ and ‘XVideos’. We have analysed 2685 TED videos from 2006 to 2018 to characterise the service. For xHamster and XVideos, active measurements were used to collect unique metadata on almost 3405 and 6721 channels from 2012 to 2019 respectively, which were then analysed. Through these characterisations we gained insight into the main players of the websites – viewers, uploaders and website owners. Our analysis involved the studying of video streaming characteristics such as views, number of uploads, ratings, tags etc. By this we aim to give an overview of the services' current state and compare them with other traditional video streaming services. Our results showed some similar trends to be observed in all three websites such as TED videos and adult channels getting a high number of views despite low injection rate, maintaining a power-law behaviour due to front page recommendations and ratings being underutilised as a feature.Other observations include adult streaming services having a higher number of subscribers per channel. The characterisation results obtained are of value to network operators, content providers, and protocol designers. These results can also be used by content providers to measure what type of content is being watched on their websites. Our study provides a glimpse at how video streaming services function today and the trends they seem to follow. •Measurements and detailed characterisation study based on TED Talks, xHamster, and XVideos.•Comprehensive understanding of the online video streaming domain.•Insights on video streaming services and how they utilise their online social network of users.