Evidence for a dual function of EphB4 as tumor promoter and suppressor regulated by the absence or presence of the ephrin-B2 ligand

Overexpression of the receptor tyrosine kinase EphB4 is common in epithelial cancers and linked to tumor progression by promoting angiogenesis, increasing survival and facilitating invasion and migration. However, other studies have reported loss of EphB4 suggesting a tumor suppressor function in some cancers. These opposing roles may be regulated by (i) the presence of the primary ligand ephrin-B2 that regulates pathways involved in tumor suppression or (ii) the absence of ephrin-B2 that allows EphB4 signaling via ligand-independent pathways that contribute to tumor promotion. To explore this theory, EphB4 was overexpressed in the prostate cancer cell line 22Rv1 and the mammary epithelial cell line MCF-10A. Overexpressed EphB4 localized to lipid-rich regions of the plasma membrane and confirmed to be ligand-responsive as demonstrated by increased phosphorylation of ERK1/2 and internalization. EphB4 overexpressing cells demonstrated enhanced anchorage-independent growth, migration and invasion, all characteristics associated with an aggressive phenotype, and therefore supporting the hypothesis that overexpressed EphB4 facilitates tumor promotion. Importantly, these effects were reversed in the presence of ephrin-B2 which led to a reduction in EphB4 protein levels, demonstrating that ligand-dependent signaling is tumor suppressive. Furthermore, extended ligand stimulation caused a significant decrease in proliferation that correlated with a rise in caspase-3/7 and -8 activities. Together, these results demonstrate that overexpression of EphB4 confers a transformed phenotype in the case of MCF-10A cells and an increased metastatic phenotype in the case of 22Rv1 cancer cells and that both phenotypes can be restrained by stimulation with ephrin-B2, in part by reducing EphB4 levels.

Muscle, skin and core temperature after −110°C cold air and 8°C water treatment

The aim of this investigation was to elucidate the reductions in muscle, skin and core temperature following exposure to −110°C whole body cryotherapy (WBC), and compare these to 8°C cold water immersion (CWI). Twenty active male subjects were randomly assigned to a 4-min exposure of WBC or CWI. A minimum of 7 days later subjects were exposed to the other treatment. Muscle temperature in the right vastus lateralis (n = 10); thigh skin (average, maximum and minimum) and rectal temperature (n = 10) were recorded before and 60 min after treatment. The greatest reduction (P<0.05) in muscle (mean ± SD; 1 cm: WBC, 1.6±1.2°C; CWI, 2.0±1.0°C; 2 cm: WBC, 1.2±0.7°C; CWI, 1.7±0.9°C; 3 cm: WBC, 1.6±0.6°C; CWI, 1.7±0.5°C) and rectal temperature (WBC, 0.3±0.2°C; CWI, 0.4±0.2°C) were observed 60 min after treatment. The largest reductions in average (WBC, 12.1±1.0°C; CWI, 8.4±0.7°C), minimum (WBC, 13.2±1.4°C; CWI, 8.7±0.7°C) and maximum (WBC, 8.8±2.0°C; CWI, 7.2±1.9°C) skin temperature occurred immediately after both CWI and WBC (P<0.05). Skin temperature was significantly lower (P<0.05) immediately after WBC compared to CWI. The present study demonstrates that a single WBC exposure decreases muscle and core temperature to a similar level of those experienced after CWI. Although both treatments significantly reduced skin temperature, WBC elicited a greater decrease compared to CWI. These data may provide information to clinicians and researchers attempting to optimise WBC and CWI protocols in a clinical or sporting setting.

Core competencies required for managing occupational road risks

To provide valuable industry information with human resource applications, this study aimed to identify the minimum level of competency required within organisations to manage occupational road risk. Senior managers from four Australian organisations participated in individual semi-structured interviews. These senior managers were responsible for a combined workforce of approximately 46,000 and a combined fleet of approximately 20,000. The managers assessed a list of 39 safety management tasks that had previously been identified as critical to the management of Occupational Health and Safety (OHS) performance within the construction industry. From this list the managers perceived that organisational personnel required competency in at least 14 of the safety tasks to meet a minimum standard of road risk management. Managers perceived that a full understanding of at least six of these tasks was critical. These six tasks comprised: hazard identification and control; providing OHS information and instruction; incident investigations; inspections of workplace and work tasks; researching and reporting on OHS issues and strategies; and applying legislative OHS requirements. It is hoped that the core competencies identified in this study may assist in the development of an internationally accepted competency framework for managing occupational road risks. This proposed competency framework could have many applications including guiding the design of job descriptions, training curriculums, and employee performance assessments. To build upon this study, the authors recommend future research be conducted to identify the key competencies required to manage occupational road safety across a broad range of organisational contexts.

Enhancing photoactivity of TiO2(B)/anatase core-shell nanofibers by selectively doping cerium ions into the TiO2(B) Core

Cerium ions (Ce3+) can beselectively doped into the TiO2(B) core of TiO2(B)/anatase core–shell nanofibers by means of a simple one-pot hydrothermal treatment of a starting material of hydrogen trititanate (H2Ti3O7) nanofibers. These Ce3+ ions (≈0.202 nm) are located on the (110) lattice planes of the TiO2(B) core in tunnels (width≈0.297 nm). The introduction of Ce3+ ions reduces the defects of the TiO2(B) core by inhibiting the faster growth of (110) lattice planes. More importantly, the redox potential of the Ce3+/Ce4+ couple (E0(Ce3+/Ce4+)=1.715 V versus the normal hydrogen electrode) is more negative than the valence band of TiO2(B). Therefore, once the Ce3+-doped nanofibers are irradiated by UV light, the doped Ce3+ ions in close vicinity to the interface between the TiO2(B) core and anatase nanoshell can efficiently trap the photogenerated holes. This facilitates the migration of holes from the anatase shell and leaves more photogenerated electrons in the anatase nanoshell, which results in a highly efficient separation of photogenerated charges in the anatase nanoshell. Hence, this enhanced charge-separation mechanism accelerates dye degradation and alcohol oxidation processes. The one-pot treatment doping strategy is also used to selectively dope other metal ions with variable oxidation states such as Co2+/3+ and Cu+/2+ ions. The doping substantially improves the photocatalytic activity of the mixed-phase nanofibers. In contrast, the doping of ions with an invariable oxidation state, such as Zn2+, Ca2+, or Mg2+, does not enhance the photoactivity of the mixed-phase nanofibers as the ions could not trap the photogenerated holes.

Saturated core high-temperature superconducting fault current limiters as an alternative to conventional series reactors in a distribution grid

Series reactors are used in distribution grids to reduce the short-circuit fault level. Some of the disadvantages of the application of these devices are the voltage drop produced across the reactor and the steep front rise of the transient recovery voltage (TRV), which generally exceeds the rating of the associated circuit breaker. Simulations were performed to compare the characteristics of a saturated core High-Temperature Superconducting Fault Current Limiter (HTS FCL) and a series reactor. The design of the HTS FCL was optimized using the evolutionary algorithm. The resulting Pareto frontier curve of optimum solution is presented in this paper. The results show that the steady-state impedance of an HTS FCL is significantly lower than that of a series reactor for the same level of fault current limiting. Tests performed on a prototype 11 kV HTS FCL confirm the theoretical results. The respective transient recovery voltages (TRV) of the HTS FCL and an air core reactor of comparable fault current limiting capability are also determined. The results show that the saturated core HTS FCL has a significantly lower effect on the rate of rise of the circuit breaker TRV as compared to the air core reactor. The simulations results are validated with shortcircuit test results.

Exponential integrators and a dual-scale model for wood drying

For the timber industry, the ability to simulate the drying of wood is invaluable for manufacturing high quality wood products. Mathematically, however, modelling the drying of a wet porous material, such as wood, is a diffcult task due to its heterogeneous and anisotropic nature, and the complex geometry of the underlying pore structure. The well{ developed macroscopic modelling approach involves writing down classical conservation equations at a length scale where physical quantities (e.g., porosity) can be interpreted as averaged values over a small volume (typically containing hundreds or thousands of pores). This averaging procedure produces balance equations that resemble those of a continuum with the exception that effective coeffcients appear in their deffnitions. Exponential integrators are numerical schemes for initial value problems involving a system of ordinary differential equations. These methods differ from popular Newton{Krylov implicit methods (i.e., those based on the backward differentiation formulae (BDF)) in that they do not require the solution of a system of nonlinear equations at each time step but rather they require computation of matrix{vector products involving the exponential of the Jacobian matrix. Although originally appearing in the 1960s, exponential integrators have recently experienced a resurgence in interest due to a greater undertaking of research in Krylov subspace methods for matrix function approximation. One of the simplest examples of an exponential integrator is the exponential Euler method (EEM), which requires, at each time step, approximation of φ(A)b, where φ(z) = (ez - 1)/z, A E Rnxn and b E Rn. For drying in porous media, the most comprehensive macroscopic formulation is TransPore [Perre and Turner, Chem. Eng. J., 86: 117-131, 2002], which features three coupled, nonlinear partial differential equations. The focus of the first part of this thesis is the use of the exponential Euler method (EEM) for performing the time integration of the macroscopic set of equations featured in TransPore. In particular, a new variable{ stepsize algorithm for EEM is presented within a Krylov subspace framework, which allows control of the error during the integration process. The performance of the new algorithm highlights the great potential of exponential integrators not only for drying applications but across all disciplines of transport phenomena. For example, when applied to well{ known benchmark problems involving single{phase liquid ow in heterogeneous soils, the proposed algorithm requires half the number of function evaluations than that required for an equivalent (sophisticated) Newton{Krylov BDF implementation. Furthermore for all drying configurations tested, the new algorithm always produces, in less computational time, a solution of higher accuracy than the existing backward Euler module featured in TransPore. Some new results relating to Krylov subspace approximation of '(A)b are also developed in this thesis. Most notably, an alternative derivation of the approximation error estimate of Hochbruck, Lubich and Selhofer [SIAM J. Sci. Comput., 19(5): 1552{1574, 1998] is provided, which reveals why it performs well in the error control procedure. Two of the main drawbacks of the macroscopic approach outlined above include the effective coefficients must be supplied to the model, and it fails for some drying configurations, where typical dual{scale mechanisms occur. In the second part of this thesis, a new dual{scale approach for simulating wood drying is proposed that couples the porous medium (macroscale) with the underlying pore structure (microscale). The proposed model is applied to the convective drying of softwood at low temperatures and is valid in the so{called hygroscopic range, where hygroscopically held liquid water is present in the solid phase and water exits only as vapour in the pores. Coupling between scales is achieved by imposing the macroscopic gradient on the microscopic field using suitably defined periodic boundary conditions, which allows the macroscopic ux to be defined as an average of the microscopic ux over the unit cell. This formulation provides a first step for moving from the macroscopic formulation featured in TransPore to a comprehensive dual{scale formulation capable of addressing any drying configuration. Simulation results reported for a sample of spruce highlight the potential and flexibility of the new dual{scale approach. In particular, for a given unit cell configuration it is not necessary to supply the effective coefficients prior to each simulation.

Video-based road commentary training improves hazard perception of young drivers in a dual task

This study used a video-based hazard perception dual task to compare the hazard perception skills of young drivers with middle aged, more experienced drivers and to determine if these skills can be improved with video-based road commentary training. The primary task required the participants to detect and verbally identify immediate hazard on video-based traffic scenarios while concurrently performing a secondary tracking task, simulating the steering of real driving. The results showed that the young drivers perceived fewer immediate hazards (mean = 75.2%, n = 24, 19 females) than the more experienced drivers (mean = 87.5%, n = 8, all females), and had longer hazard perception times, but performed better in the secondary tracking task. After the road commentary training, the mean percentage of hazards detected and identified by the young drivers improved to the level of the experienced drivers and was significantly higher than that of an age and driving experience matched control group. The results will be discussed in the context of psychological theories of hazard perception and in relation to road commentary as an evidence-based training intervention that seems to improve many aspects of unsafe driving behaviour in young drivers.

Water end use consumption analysis study into Gold Coast dual reticulated households : pilot study

Australia is the driest inhabited continent in the world and persisting droughts have triggered a move toward sensible and sustainable water consumption. Understanding how and where water is consumed in households enables streamlined development of demand management programs and efficient engineering of water infrastructure. End use water consumption analysis is required to gain necessary empirical data of how and where water is consumed. Several end use water consumption studies have been conducted within Australia and around the world with varying results produced. This pilot study paper provides preliminary data from the Gold Coast Watersaver End Use Project which is currently underway. Specifically, the paper includes water end use category volumetric and percentage break downs for 18 single and 32 dual reticulated homes on the Gold Coast (i.e. 50 in total). Moreover, a comparitive analysis between each of the individual households water end use levels is discussed along with other national studies previously completed. The paper finishes with an overview of the greater 200 home end use study conducted on the Gold Coast and its key deliverables and research outcomes.

Core principles of CSR approaches

CSR is increasingly an essential issue for business enterprises. It is a company and multidimensional organizational ...

Communication and the casualisation of nursing : a critical ethnography

The contemporary working environment is being rapidly reshaped by technological, industrial and political forces. Increased global competitiveness and an emphasis on productivity have led to the appearance of alternative methods of employment, such as part-time, casual and itinerant work, allowing greater flexibility. This allows for the development of a core permanent staff and the simultaneous utilisation of casual staff according to business needs. Flexible workers across industries are generally referred to as the non-standard workforce and full-time permanent workers as the standard workforce. Even though labour flexibility favours the employer, increased opportunity for flexible work has been embraced by women for many reasons, including the gender struggle for greater economic independence and social equality. Consequently, the largely female nursing industry, both nationally and internationally, has been caught up in this wave of change. This ageing workforce has been at the forefront of the push for flexibility with recent figures showing almost half the nursing workforce is employed in non-standard capacity. In part, this has allowed women to fulfil caring roles outside their work, to ease off nearing retirement and to supplement the family income. More significantly, however, flexibility has developed as an economic management initiative, as a strategy for cost constraint. The result has been the development of a dual workforce and as suggested by Pocock, Buchanan and Campbell (2004), associated deep-seated resentment and the marginalisation of part-time and casual workers by their full-time colleagues and managers. Additionally, as nursing currently faces serious recruitment and retention problems there is urgent need to understand the factors which are underlying present discontent in the nursing profession. There is an identified gap in nursing knowledge surrounding the issues relating to recruitment and retention. Communication involves speaking, listening, reading and writing and is an interactive process which is central to the lives of humans. Workplace communication refers to human interaction, information technology, and multimedia and print. It is the means to relationship building between workers, management, and their external environment and is critical to organisational effectiveness. Communication and language are integral to nursing performance (Hall, 2005), in twenty-four hour service however increasing fragmentation due to part-time and casual work in the nursing industry means that effective communication management has become increasingly difficult. More broadly it is known that disruption to communication systems impacts negatively on consumer outcomes. Because of this gap in understanding how nurses view their contemporary nursing world, an interpretative ethnographic study which progressed to a critical ethnographic study, based on the conceptual framework of constructionism and interpretativism was used. The study site was a division within an acute health care facility, and the relationship between increasing casualisation of the nursing workforce and the experiences of communication of standard and non-standard nurses was explored. For this study, full-time standard nurses were those employed to work in a specific unit for forty hours per week. Non-standard nurses were those employed part-time in specific units or those nurses employed to work as relief pool nurses for shift short falls where needed. Nurses employed by external agencies, but required to fill in for shifts at the facility were excluded from this research. This study involved an analysis of observational, interview and focus group data of standard and non-standard nurses within this facility. Three analytical findings - the organisation of nursing work; constructing the casual nurse as other; and the function of space, situate communication within a broader discussion about non-standard work and organisational culture. The study results suggest that a significant culture of marginalisation exists for nurses who work in a non-standard capacity and that this affects communication for nurses and has implications for the quality of patient care. The discussion draws on the seven elements of marginalisation described by Hall, Stephen and Melius (1994). The arguments propose that these elements underpin a culture which supports remnants of the historically gendered stereotype "the good nurse" and these cultural values contribute to practices and behaviour which marginalise all nurses, particularly those who work less than full-time. Gender inequality is argued to be at the heart of marginalising practices because of long standing subordination of nurses by the powerful medical profession, paralleling historical subordination of women in society. This has denied nurses adequate representation and voice in decision making. The new knowledge emanating from this study extends current knowledge of factors surrounding recruitment and retention and as such contributes to an understanding of the current and complex nursing environment.

A comprehensive dual-scale wood torrefaction model : application to the analysis of thermal run-away in industrial heat treatment processes

A dual-scale model of the torrefaction of wood was developed and used to study industrial configurations. At the local scale, the computational code solves the coupled heat and mass transfer and the thermal degradation mechanisms of the wood components. At the global scale, the two-way coupling between the boards and the stack channels is treated as an integral component of the process. This model is used to investigate the effect of the stack configuration on the heat treatment of the boards. The simulations highlight that the exothermic reactions occurring in each single board can be accumulated along the stack. This phenomenon may result in a dramatic eterogeneity of the process and poses a serious risk of thermal runaway, which is often observed in industrial plants. The model is used to explain how thermal runaway can be lowered by increasing the airflow velocity, the sticker thickness or by gas flow reversal.

Knowledge transfer through dual degree programs between Australian and Indonesian universities : a case study

While dual degree programs (DDPs) between Australian and Indonesian universities are expected to facilitate knowledge transfer (KT) between the partnering universities, little is known about how and what KT process taking place within DDP partnerships. Using an inter-organisational KT framework, this study investigated Indonesian universities’ rationales and outcomes of establishing DDPs and mechanisms facilitating knowledge transfer between Australian and Indonesian universities. Two Indonesian universities along with their common Australian partner university participated in this case study. Semi-structured interviews were conducted with 27 key university officers and pertinent university documents provided the main data. Both data sources were thematically analysed to identify emerging patterns. The findings suggest that Indonesian universities prioritised developing capacity to improve their international recognition more than the Australian partner. Consequently, the DDPs benefited the Indonesian universities through capacity development made possible by KT from the Australian DDP partners. KT processes occurred in DDP partnerships, particularly through curriculum collaboration, but they were more limited for the managerial area. Factors enabling the KT included both technology-aided and face-to-face communication, intention to acquire knowledge from the partners, capitalising on the unequal power relations to advance KT opportunities, and knowledge management system. The findings of this study suggest the importance of prioritising capacity development in DDP partnerships to enable KT, executing the KT stages to ensure institutionalisation of acquired knowledge into the university’s systems and policies, and maintaining financial sustainability of the DDPs to reach mutually beneficial outcomes between Australian and Indonesian universities.

How approach and avoidance constructs of personality and trait emotional intelligence predict core human values

In this paper we focus specifically on explaining variation in core human values, and suggest that individual differences in values can be partially explained by personality traits and the perceived ability to manage emotions in the self and others (i.e. trait emotional intelligence). A sample of 209 university students was used to test hypotheses regarding several proposed direct and indirect relationships between personality traits, trait emotional intelligence and values. Consistent with the hypotheses, Harm Avoidance and Novelty Seeking were found to directly predict Hedonism, Conformity, and Stimulation. Harm Avoidance was also found to indirectly predict these values through the mediating effects of key subscales of trait emotional intelligence. Novelty Seeking was not found to be an indirect predictor of values. Results have implications for our understanding of the relationship between personality, trait emotional intelligence and values, and suggest a common basis in terms of approach and avoidance pathways.