A novel population balance model for the dilute acid hydrolysis of hemicellulose

Acid hydrolysis is a popular pretreatment for removing hemicellulose from lignocelluloses in order to produce a digestible substrate for enzymatic saccharification. In this work, a novel model for the dilute acid hydrolysis of hemicellulose within sugarcane bagasse is presented and calibrated against experimental oligomer profiles. The efficacy of mathematical models as hydrolysis yield predictors and as vehicles for investigating the mechanisms of acid hydrolysis is also examined. Experimental xylose, oligomer (degree of polymerisation 2 to 6) and furfural yield profiles were obtained for bagasse under dilute acid hydrolysis conditions at temperatures ranging from 110C to 170C. Population balance kinetics, diffusion and porosity evolution were incorporated into a mathematical model of the acid hydrolysis of sugarcane bagasse. This model was able to produce a good fit to experimental xylose yield data with only three unknown kinetic parameters ka, kb and kd. However, fitting this same model to an expanded data set of oligomeric and furfural yield profiles did not successfully reproduce the experimental results. It was found that a ``hard-to-hydrolyse'' parameter, $\alpha$, was required in the model to ensure reproducibility of the experimental oligomer profiles at 110C, 125C and 140C. The parameters obtained through the fitting exercises at lower temperatures were able to be used to predict the oligomer profiles at 155C and 170C with promising results. The interpretation of kinetic parameters obtained by fitting a model to only a single set of data may be ambiguous. Although these parameters may correctly reproduce the data, they may not be indicative of the actual rate parameters, unless some care has been taken to ensure that the model describes the true mechanisms of acid hydrolysis. It is possible to challenge the robustness of the model by expanding the experimental data set and hence limiting the parameter space for the fitting parameters. The novel combination of ``hard-to-hydrolyse'' and population balance dynamics in the model presented here appears to stand up to such rigorous fitting constraints.

Key beliefs of hospital nurses’ hand-hygiene behaviour: Protecting your peers and needing effective reminders

Issues addressed: Hand hygiene in hospitals is vital to limit the spread of infections. This study aimed to identify key beliefs underlying hospital nurses’ hand-hygiene decisions to consolidate strategies that encourage compliance. Methods: Informed by a theory of planned behaviour belief framework, nurses from 50 Australian hospitals (n = 797) responded to how likely behavioural beliefs (advantages and disadvantages), normative beliefs (important referents) and control beliefs (barriers) impacted on their hand-hygiene decisions following the introduction of a national ‘5 moments for hand hygiene’ initiative. Two weeks after completing the survey, they reported their hand-hygiene adherence. Stepwise regression analyses identified key beliefs that determined nurses’ hand-hygiene behaviour. Results: Reducing the chance of infection for co-workers influenced nurses’ hygiene behaviour, with lack of time and forgetfulness identified as barriers. Conclusions: Future efforts to improve hand hygiene should highlight the potential impact on colleagues and consider strategies to combat time constraints, as well as implementing workplace reminders to prompt greater hand-hygiene compliance. So what? Rather than emphasising the health of self and patients in efforts to encourage hand-hygiene practices, a focus on peer protection should be adopted and more effective workplace reminders should be implemented to combat forgetting.

Developing an epidemic forecasting model for Influenza A in Brisbane, Australia, based on climate and Hong Kong Influenza A surveillance data

Influenza is associated with substantial disease burden [ 1]. Development of a climate-based early warning system for in fluenza epidemics has been recommended given the signi fi - cant association between climate variability and influenza activity [2]. Brisbane is a subtropical city in Australia and offers free in fluenza vaccines to residents aged ≥65 years considering their high risks in developing life-threatening complications, especially for in fluenza A predominant seasons. Hong Kong is an international subtropical city in Eastern Asia and plays a crucial role in global infectious diseases transmission dynamics via the international air transportation network [3, 4]. We hypothesized that Hong Kong in fluenza surveillance data could provide a signal for in fluenza epidemics in Brisbane [ 4]. This study aims to develop an epidemic forecasting model for influenza A in Brisbane elders, by combining climate variability and Hong Kong in fluenza A surveillance data. Weekly numbers of laboratoryconfirmed influenza A positive isolates for people aged ≥65 years from 2004 to 2009 were obtained for Brisbane from Queensland Health, Australia, and for Hong Kong from Queen Mary Hospital (QMH). QMH is the largest public hospital located in Hong Kong Island, and in fluenza surveillance data from this hospital have been demonstrated to be representative for influenza circulation in the entirety of Hong Kong [ 5]. The Brisbane in fluenza A epidemics occurred during July –September, whereas the Hong Kong in fluenza A epidemics occurred during February –March and May –August.

Consumer preferences for teledermoscopy screening to detect melanoma early

- Introduction ‘Store and forward’ teledermoscopy is a technology with potential advantages for melanoma screening. Any large-scale implementation of this technology is dependent on consumer acceptance. - Aim To investigate preferences for melanoma screening options compared to skin selfexamination in adults considered to be at increased risk of developing skin cancer. - Methods A discrete choice experiment (DCE) was completed by 35 consumers, all of whom had prior experience with the use of teledermoscopy, in Queensland, Australia. Participants made 12 choices between screening alternatives described by seven attributes including monetary cost. A mixed logit model was used to estimate the relative weights that consumers place on different aspects of screening, along with the marginal willingness to pay for teledermoscopy as opposed to screening at a clinic. - Results Overall, participants preferred screening/diagnosis by a health professional rather than skin self-examination. Key drivers of screening choice were for results to be reviewed by a dermatologist; a higher detection rate; fewer non-cancerous moles being removed in relation for every skin cancer detected; and less time spent away from usual activities. On average, participants were willing to pay AU$110 to have teledermoscopy with dermatologist review available to them as a screening option. - Discussion & Conclusions Consumers preferentially value aspects of care that are more feasible with a teledermoscopy screening model, as compared to other skin cancer screening and diagnosis options. This study adds to previous literature in the area which has relied on the use of consumer satisfaction scales to assess the acceptability of teledermoscopy.

Melanoma cell colony expansion parameters revealed by approximate Bayesian computation

In vitro studies and mathematical models are now being widely used to study the underlying mechanisms driving the expansion of cell colonies. This can improve our understanding of cancer formation and progression. Although much progress has been made in terms of developing and analysing mathematical models, far less progress has been made in terms of understanding how to estimate model parameters using experimental in vitro image-based data. To address this issue, a new approximate Bayesian computation (ABC) algorithm is proposed to estimate key parameters governing the expansion of melanoma cell (MM127) colonies, including cell diffusivity, D, cell proliferation rate, λ, and cell-to-cell adhesion, q, in two experimental scenarios, namely with and without a chemical treatment to suppress cell proliferation. Even when little prior biological knowledge about the parameters is assumed, all parameters are precisely inferred with a small posterior coefficient of variation, approximately 2–12%. The ABC analyses reveal that the posterior distributions of D and q depend on the experimental elapsed time, whereas the posterior distribution of λ does not. The posterior mean values of D and q are in the ranges 226–268 µm2h−1, 311–351 µm2h−1 and 0.23–0.39, 0.32–0.61 for the experimental periods of 0–24 h and 24–48 h, respectively. Furthermore, we found that the posterior distribution of q also depends on the initial cell density, whereas the posterior distributions of D and λ do not. The ABC approach also enables information from the two experiments to be combined, resulting in greater precision for all estimates of D and λ.

Establishing a participatory library model: A Grounded Theory study

Purpose The purpose of this research is to explore the idea of the participatory library in higher education settings. This research aims to address the question, what is a participatory university library? Design/methodology/approach Grounded theory approach was adopted. In-depth individual interviews were conducted with two diverse groups of participants including ten library staff members and six library users. Data collection and analysis were carried out simultaneously and complied with Straussian grounded theory principles and techniques. Findings Three core categories representing the participatory library were found including “community”, “empowerment”, and “experience”. Each category was thoroughly delineated via sub-categories, properties, and dimensions that all together create a foundation for the participatory library. A participatory library model was also developed together with an explanation of model building blocks that provide a deeper understanding of the participatory library phenomenon. Research limitations The research focuses on a specific library system, i.e., academic libraries. Therefore, the research results may not be very applicable to public, special, and school library contexts. Originality/value This is the first empirical study developing a participatory library model. It provides librarians, library managers, researchers, library students, and the library community with a holistic picture of the contemporary library.

A hierarchical model of social marketing

Purpose This paper aims to set out a new hierarchical and differentiated model of social marketing principles, concepts and techniques that builds on, but supersedes, the existing lists of non-equivalent and undifferentiated benchmark criteria. Design/methodology/approach This is a conceptual paper that proposes a hierarchical model of social marketing principles, concepts and techniques. Findings This new delineation of the social marketing principle, its four core concepts and five techniques, represents a new way to conceptualize and recognize the different elements that constitute social marketing. This new model will help add to and further the development of the theoretical basis of social marketing, building on the definitional work led by the International Social Marketing Association (iSMA), Australian Association of Social Marketing (AASM) and European Social Marketing Association (ESMA). Research limitations/implications This proposed model offers a foundation for future research to expand upon. Further research is recommended to empirically test the proposed model. Originality/value This paper seeks to advance the theoretical base of social marketing by making a reasoned case for the need to differentiate between principles, concepts and techniques when seeking to describe social marketing.

Investigating the factors influencing the adoption of m-banking: A cross cultural study

Purpose Little is known about the adoption of mobile banking technologies in emerging Asian economies. This paper aims to empirically examine the motivators that influence a consumer’s intentions to use mobile banking. Design/methodology/approach A web-based survey was employed to collect data from 348 respondents, split across Thailand and Australia. Data were analyzed by employing exploratory and confirmatory factor analyses, path and invariance analyses. Findings The findings indicate that for Australian consumers, perceived ease of use, perceived usefulness and perceived risk were the primary determinants of mobile banking adoption. For Thai consumers, the main factors were perceived usefulness, perceived risk and social influence. National culture was found to impact key antecedents that lead to adoption of m-banking. Research limitations/implications The actual variance explained by our study’s model was higher in Australia (59.3%) than for Thailand (23.8%), suggesting future research of m-banking adoption in emerging Asian cultures. Practical implications We identify the important factors consumers consider when adopting m-banking. The findings of this research give banking organisations a foundational model that can be used to support m-banking implementation. Originality/value Our study is perhaps the first to examine and compare the intention to adopt m-banking across Thai and Australian consumers, and responds to calls for additional research that generalises m-banking and m-services acceptance across cultures. This study has proposed and validated additional constructs that are not present in the original SST Intention to Use model.

Curating in uncharted territories: An examination of a programming model & communicative platform for curation in non-traditional art spaces

This thesis articulates and examines public engagement programming in an emerging, non¬-traditional site. As a practice-led research project, the creative work proposes a site responsive, engagement centric, agile model for curatorial programming that developed out of the dynamic, new media/digital, curatorial practice at QUT's Creative Industries Precinct. The model and its accompanying exegetical framework, Curating in Uncharted Territories, offer a theoretically informed approach to programming, delivering and reporting for curatorial practices in a non¬-traditional sites of public engagement. The research provides the foundation for full development of the model and the basis for further research.

A developmental cascade model of behavioral sleep problems and emotional and attentional self-regulation across early childhood

This paper documents the longitudinal and reciprocal relations among behavioral sleep problems, emotional and attentional self-regulation in a population sample of 4109 children participating in the Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC) – Infant Cohort. Maternal reports of children’s sleep problems and self-regulation were collected at five time points from infancy to 8-9 years of age. Longitudinal structural equation modeling supported a developmental cascade model in which sleep problems have a persistent negative effect on emotional regulation, which in turn contributes to ongoing sleep problems and poorer attentional regulation in children over time. Findings suggest that sleep behaviors are a key target for interventions that aim to improve children’s self-regulatory capacities.

The organisational context of nursing care in stroke units: A case study approach

Background Internationally the stroke unit is recognised as the evidence-based model for patient management, although clarity about the effective components of stroke units is lacking. Whilst skilled nursing care has been proposed as one component, the theoretical and empirical basis for stroke nursing is limited. We attempted to explore the organisational context of stroke unit nursing, to determine those features that staff perceived to be important in facilitating high quality care. Design A case study approach was used, that included interviews with nurses and members of the multidisciplinary teams in two Canadian acute stroke units. A total of 20 interviews were completed, transcribed and analysed thematically using the Framework Approach. Trustworthiness was established through the review of themes and their interpretation by members of the stroke units. Findings Nine themes that comprised an organisational context that supported the delivery of high quality nursing care in acute stroke units were identified, and provide a framework for organisational development. The study highlighted the importance of an overarching service model to guide the organisation of care and the development of specialist and advanced nursing roles. Whilst multidisciplinary working appears to be a key component of stroke unit nursing, various organisational challenges to its successful implementation were highlighted. In particular the consequence of differences in the therapeutic approach of nurses and therapy staff needs to be explored in greater depth. Successful teamwork appears to depend on opportunities for the development of relationships between team members as much as the use of formal communication systems and structures. A co-ordinated approach to education and training, clinical leadership, a commitment to research, and opportunities for role and practice development also appear to be key organisational features of stroke unit nursing. Recommendations for the development of stroke nursing leadership and future research into teamwork in stroke settings are made.

A comprehensive mechanistic kinetic model for dilute acid hydrolysis of switchgrass cellulose to glucose, 5-HMF and levulinic acid

Switchgrass was treated by 1% (w/w) H₂SO₄in batch tube reactors at temperatures ranging from 140–220°C for up to 60 minutes. In this study, release patterns of glucose, 5-hydroxymethylfurfural (5-HMF), and levulinic acid from switchgrass cellulose were investigated through a mechanistic kinetic model. The predictions were consistent with the measured products of interest when new parameters reflecting the effects of reaction limitations, such as cellulose crystallinity, acid soluble lignin–glucose complex (ASL–glucose) and humins that cannot be quantitatively analyzed, were included. The new mechanistic kinetic model incorporating these parameters simulated the experimental data with R² above 0.97. Results showed that glucose yield was most sensitive to variations in the parameter regarding the cellulose crystallinity at low temperatures (140–180°C), while the impact of crystallinity on the glucose yield became imperceptible at elevated temperatures (200–220 °C). Parameters related to the undesired products (e.g. ASL–glucose and humins) were the most sensitive factors compared with rate constants and other additional parameters in impacting the levulinic acid yield at elevated temperatures (200–220°C), while their impacts were negligible at 140–180°C. These new findings provide a more rational explanation for the kinetic changes in dilute acid pretreatment performance and suggest that the influences of cellulose crystallinity and undesired products including ASL–glucose and humins play key roles in determining the generation of glucose, 5-HMF and levulinic acid from biomass-derived cellulose.

Public use and perceptions of emergency departments: A population survey

Objectives To inform demand management strategies aimed at reducing congestion in EDs by: (i) identifying public use of EDs, decision-making and reasons; and (ii) measuring acceptance of alternative care models. Methods A cross-sectional telephone survey of a random sample of Queensland population aged 18 years or older residing in a dwelling unit in Queensland that could be contacted on a land-based telephone service was conducted. One person per household was selected according to a predetermined algorithm to ensure sex and regional balance were interviewed. The main outcome measures were: ED use, attitudes towards ED staff and services, and alternative models of care. Results The final sample included a total of 1256 respondents (response rate = 40.3%). Twenty-one per cent attended EDs in the preceding 12 months. The decision to attend was made by patients (51%), health and medical professionals (31%), and others (18%). The main reasons included perceived severity of the illness (47%), unavailability of alternative services (26%) and better care (11%). Most respondents agreed with more flexible care models of service delivery including incentives for general practitioners (90%), private health insurance coverage for ED use (89%), and enhanced roles for paramedics and nurses. Conclusions Main reason for attending ED is perceived severity of illness, followed by lack of alternative care. The majority of both consumers and the public are in favour of more flexible care models. However, further research is necessary to detail those alternatives and to test and validate their effectiveness.

The dead poets society: The copyright term and the public domain

In a victory for corporate control of cultural heritage, the Supreme Court of the United States has rejected a constitutional challenge to the Sonny Bono Copyright Term Extension Act 1998 (U.S.) by a majority of seven to two. This paper evaluates the litigation in terms of policy debate in a number of discourses — history, intellectual property law, constitutional law and freedom of speech, cultural heritage, economics and competition policy, and international trade. It argues that the extension of the copyright term will inhibit the dissemination of cultural works through the use of new technologies — such as Eric Eldred's Eldritch Press and Project Gutenberg. It concludes that there is a need to resist the attempts of copyright owners to establish the Sonny Bono Copyright Term Extension Act 1998 (U.S.) as an international model for other jurisdictions — such as Australia.

Determining the drivers of m-banking adoption: A cross cultural study

This study empirically examines the motivators that influence a consumer’s intentions to use mobile banking. A web-based survey was employed to collect data from 348 respondents, split across Thailand and Australia. Data were analysed by employing exploratory and confirmatory factor analyses, path and invariance analyses. The findings indicate that for Australian consumers, perceived ease of use, perceived usefulness and perceived risk were the primary determinants of mobile banking adoption. For Thai consumers, the main factors were perceived usefulness, perceived risk and social influence. National culture was found to impact key antecedents that lead to adoption of m-banking. Interestingly, the actual variance explained by this study’s model was higher in Australia than for Thailand, suggesting future research of m-banking adoption in emerging Asian cultures. The findings of this research give banking organisations a foundational model that can be used to support m-banking implementation. This study is perhaps the first to examine and compare the intention to adopt m-banking across Thai and Australian consumers, and responds to calls for additional research that generalises m-banking and m-services acceptance across cultures. This study has proposed and validated additional constructs that are not present in the original SST Intention to Use model.