963 resultados para tense and aspect
Resumo:
The aim of the current study was to examine the dimensions and reliability of a hospital safety climate questionnaire in Chinese health-care practice. To achieve this, a cross-sectional survey of health-care professionals was undertaken at a university teaching hospital in Shandong province, China. Our survey instrument demonstrated very high internal consistency, comparing well with previous research in this field conducted in other countries. Factor analysis highlighted four key dimensions of safety climate, which centred on employee personal protection, employee interactions, safetyrelated housekeeping and time pressures. Overall, this study suggests that hospital safety climate represents an important aspect of health-care practice in contemporary China.
Resumo:
Prostate cancer is the most commonly diagnosed malignancy and the second leading cause of cancer related deaths in Australian men. Treatment in the early stages of the disease involves surgery, radiation and/or hormone therapy. However, in late stages of the disease these treatments are no longer effective and only palliative care is available. Therefore, there is a focus on exploration of novel therapies to increase survival and treatment efficacy. Advanced prostate cancer is characterised by bone or other distant metastasis. Spreading of the primary tumour to a secondary location is a complex process requiring an initial loss in cell-cell adhesion followed by increased cell migration and invasion. One gene family that has been known to affect cell-to-cell contact in other model systems are the Eph receptor tyrosine kinases. They are the largest family of receptor tyrosine kinases made up of 14 vertebrate Eph receptors that bind to nine cell membrane bound ephrin ligands. Eph-ephrin interaction is crucial in regulating cell behaviour in developmental processes and it is now thought that the underlying mechanisms involved in development may also be involved in cancer. Aberrant expression has been reported in many human malignancies including prostate cancer. Furthermore, expression has been linked with metastasis and poor prognosis in other tumour models. This study explores the potential role of the Eph receptor family in prostate cancer, in particular the roles of EphA2, EphA3 and ephrin-A5. Gene expression profiles were established for the Eph family in a series of prostate cancer cell lines using quantitative real time RT-PCR. A smaller subset of the most prominently expressed genes was chosen to screen a cohort of clinical samples. Elevated levels of EphA2, EphA3 and their ligands, ephrin-A1 and ephrin-A5 were observed in individual cell lines. Interestingly high EphA3 expression was observed in the androgen responsive cell lines while EphA2 was more prominent in the androgen independent cell lines. However, studies using 5-dihydrotestosterone suggest that EphA3 expression in not regulated by androgen. Cells expressing EphA2 showed a greater ability for migration and invasion while cells expressing EphA3 showed poor migration and invasion. Forced expression of EphA2 in the LNCaP cell line resulted in a more invasive phenotype while forced expression of EphA3 in the PC-3 cell line suggests a possible negative effect for EphA3 on cell migration and invasion. Cell signalling studies show activation of EphA2 decreases activity of proteins thought to be involved in pathways regulating cell movement including Akt, Src and FAK. Changes to the activation status of Rho family members, including RhoA and Rac1, associated with reorganisation of the actin cytoskeleton, an important part of cell migration was also observed. As a result, activation of EphA2 in PC-3 cells resulted in a less invasive phenotype. A novel finding in this study was the discovery of a combination of two EphA2 Mabs able to activate EphA2. Preliminary results show a potential for this antibody combination to reduce prostate cancer invasion in vitro. A unique aspect of Eph-ephrin interaction is the resulting bi-directional signalling that occurs through both the receptor and ligand. In this study a potential role for ephrin-A5 mediated signalling in prostate cancer was observed. LNCaP cells express high levels of EphA3 and its high affinity ligand ephrin-A5. In stripe assays, used to study guidance cues, LNCaP cells show strong attraction/migration to EphA3-Fc stripes but not ephrin-A5-Fc stripes suggesting ephrin-A5 mediated reverse cell signalling is involved. Knockdown of ephrin-A5 using shRNA resulted in a decrease in attraction/migration to EphA3-Fc stripes. Furthermore a reduction in proliferation was also observed in vitro. A subcutaneous xenograft model using ephrin-A5 shRNA cells versus controls showed a decrease in tumour formation. This study demonstrates a difference in EphA2 and EphA3 function in prostate cancer migration/invasion and a potential role for ephrin-A5 in prostate cancer cell adhesion and growth.
Resumo:
Chemically synthesized AgTCNQ exists in two forms that differ in their morphologies (needles and microcrystals) and colors (red and blue). It is now shown that both forms exhibit essentially indistinguishable X-ray diffraction, spectroscopic, and thermochemical data, implying that they are not separate phases, as implied in some literature. Electrochemical reduction of TCNQ((MeCN)) in the presence of Ag+((MeCN)) generates both red and blue AgTCNQ. On glassy carbon, platinum, or indium tin oxide electrodes and at relatively positive deposition potentials, slow growth of high aspect ratio, red needle AgTCNQ crystals occurs. After longer times and at more negative deposition potentials, blue microcrystalline AgTCNQ thin films are favored. Blue AgTCNQ is postulated to be generated via reduction of a Ag+\[(TCNQ(center dot-))(TCNQ)]((MeCN)) intermediate. At even more negative potentials, Ag-(metal) formation inhibits further growth of AgTCNQ. On a gold electrode, Ag-(metal)) deposition occurs at more positive potentials than on the other electrode materials examined. However, surface plasmon resonance data indicate (hat a small potential region is available between the stripping of Ag-(metal)) and the oxidation of TCNQ(center dot-)(MeCN) back to TCNQ(MeCN) where AgTCNQ may form. AgTCNQ in both the red and blue forms also can be prepared electrochemically on a TCNQ((s)) modified electrode in -0.1 M AgNO3(aq) where deposition of Ag(m,,,I) onto the TCNQ((s)) crystals allows a charge transfer process to occur. However, the morphology formed in this solid-solid phase transformation is more difficult to control.
Resumo:
The ‘war on terror’ and ongoing terrorist attacks around the world have generated a growing body of literature on national and international measures to counteract terrorist activity. This detailed study investigates an aspect of contemporary counter-terrorism that has been largely overlooked; the impact of these measures on the continued viability of the democratic state.
Resumo:
Mobility across space is an exemplary characteristic of the global era and an important aspect of the cultural experience of many people in advanced industrialised nations. Mobility evokes powerful images that effectively counter any illusion of stationary life and provide a break from the insularity of the local and parochial. High levels of mobility are simultaneously a fact, a necessity and a cultural aspiration. In recent times, debates about mobility in social theory have considered the relationship between mobility and cosmopolitan culture and identities (Hannerz, 1990, Urry, 1990, 2000, Beck, 2006). Against this backdrop, this paper also draws on some of the more recent discussions about the emergence of globalised and cosmopolitan identities among young people (Beck and Beck-Gernsheim, 2009). Using data from a longitudinal study of young people in Queensland, this paper provides an insight into young people’s aspirations about future mobility. The data affirm Skeggs’ (2004) comment that mobility is an unequal resource, and demonstrate that aspirations of future mobility reflect numerous social, economic and cultural realities of young people’s lives. This inevitably leads us to problematise the established, and often abstract, nexus between cosmopolitanism and mobility in contemporary debates about cosmopolitanism.
Resumo:
A long query provides more useful hints for searching relevant documents, but it is likely to introduce noise which affects retrieval performance. In order to smooth such adverse effect, it is important to reduce noisy terms, introduce and boost additional relevant terms. This paper presents a comprehensive framework, called Aspect Hidden Markov Model (AHMM), which integrates query reduction and expansion, for retrieval with long queries. It optimizes the probability distribution of query terms by utilizing intra-query term dependencies as well as the relationships between query terms and words observed in relevance feedback documents. Empirical evaluation on three large-scale TREC collections demonstrates that our approach, which is automatic, achieves salient improvements over various strong baselines, and also reaches a comparable performance to a state of the art method based on user’s interactive query term reduction and expansion.
Resumo:
The present paper explores extreme car audio systems and the culture and practices that surround car audio competitions. I begin by examining whether, and how, car audio can be thought of as a 'music scene' and in what ways the culture and practice of car audio may fit within post-subcultural discourses. Following this, I offer a description of car audio competitions, revealing some of the practices that define this aspect of car audio scenes. In particular, I concentrate on sound pressure level (SPL) competitions and some of the interesting aspects of the SPL scene. Finally, I briefly examine how the powerful effects (and affects) of bass frequencies are an important part of the attraction of loud car audio systems and how car audio systems contribute to the territorializing of urban spaces.
Resumo:
In light of the time available today, I will limit my comments to addressing that aspect of Professor Fletcher’s paper in which he refers to the 2012 report he co-authored with Professor Wessels of the Netherlands for the American Law Institute (ALI) and the International Insolvency Institute (III) on Transnational Insolvency: Global Principles for Cooperation in International Insolvency Cases. I will comment on the potential benefits for Australian courts as well as insolvency administrators and their advisers in referring to the ALI-III Report - in light of Australia’s adoption of the UNCITRAL Model Law. In so doing, I would like to acknowledge the support of the Australian Academy of Law, under the leadership of The Hon Dr Kevin Lindgren for the research project underpinning these comments, as well as to acknowledge the contributions of my colleagues Associate Professor Sheryl Jackson and Mark Wellard.
Resumo:
An increasing number of countries are faced with an aging population increasingly needing healthcare services. For any e-health information system, the need for increased trust by such clients with potentially little knowledge of any security scheme involved is paramount. In addition notable scalability of any system has become a critical aspect of system design, development and ongoing management. Meanwhile cryptographic systems provide the security provisions needed for confidentiality, authentication, integrity and non-repudiation. Cryptographic key management, however, must be secure, yet efficient and effective in developing an attitude of trust in system users. Digital certificate-based Public Key Infrastructure has long been the technology of choice or availability for information security/assurance; however, there appears to be a notable lack of successful implementations and deployments globally. Moreover, recent issues with associated Certificate Authority security have damaged trust in these schemes. This paper proposes the adoption of a centralised public key registry structure, a non-certificate based scheme, for large scale e-health information systems. The proposed structure removes complex certificate management, revocation and a complex certificate validation structure while maintaining overall system security. Moreover, the registry concept may be easier for both healthcare professionals and patients to understand and trust.
Resumo:
Global climate change is one of the most significant environmental issues that can harm human development. One central issue for the building and construction industry to address global climate change is the development of a credible and meaningful way to measure greenhouse gas (GHG) emissions. While Publicly Available Specification (PAS) 2050, the first international GHG standard, has been proven to be successful in standardizing the quantification process, its contribution to the management of carbon labels for construction materials is limited. With the recent publication of ISO 14067: Greenhouse gases – carbon footprint of products – requirements and guidelines for quantification and communication in May 2013, it is necessary for the building and construction industry to understand the past, present and future of the carbon labelling practices for construction materials. A systematic review shows that international GHG standards have been evolving in terms of providing additional guidance on communication and comparison, as well as less flexibility on the use of carbon labels. At the same time, carbon labelling schemes have been evolving on standardization and benchmarking. In addition, future actions are needed in the aspect of raising consumer awareness, providing benchmarking, ensuring standardization and developing simulation technologies in order for carbon labelling schemes for construction materials to provide credible, accurate and transparent information on GHG emissions.
Resumo:
Cold-formed steel members are increasingly used as primary structural elements in buildings due to the availability of thin and high strength steels and advanced cold-forming technologies. Cold-formed lipped channel beams (LCB) are commonly used as flexural members such as floor joists and bearers. Many research studies have been carried out to evaluate the behaviour and design of LCBs subject to pure bending actions. However, limited research has been undertaken on the shear behaviour and strength of LCBs. Hence a numerical study was undertaken to investigate the shear behaviour and strength of LCBs. Finite element models of simply supported LCBs with aspect ratios of 1.0 and 1.5 were considered under a mid-span load. They were then validated by comparing their results with test results and used in a detailed parametric study based on the validated finite element models. Numerical studies were conducted to investigate the shear buckling and post-buckling behaviour of LCBs. Experimental and numerical results showed that the current design rules in cold-formed steel structures design codes are very conservative for the shear design of LCBs. Improved design equations were therefore proposed for the shear strength of LCBs. This paper presents the details of this numerical study of LCBs and the results.
Resumo:
Safety climate is a current interest to construction practitioners and researchers. The concept of safety climate has been actively explored in the field of Industrial and Organizational (I/O) psychology but yet in the construction industry. This paper aims to review the literature of safety climate in a systematic manner and highlight future directions for safety research and development of safety practices in the construction industry. The value of safety climate lies on its ability to predict safety behavior. Safety climate, as a mediator, unfolds the relationship between organizational variables and safety behavior. It, as a moderator, affects the effectiveness of any safety initiatives to improve safety performance. Future research directions would be likely to look at relationship between organizational factors and safety climate using multi-level analysis. To the construction industry, safety climate measurement is a good indicator to assess safety performance. Empirical studies show that frontline supervisor would be the best conduit to create a positive safety climate at workgroup level. It is believed that this paper is beneficial to researchers interested in behavioral aspect of construction safety and industry practitioners striving for safety on site.
Resumo:
Analysis of behavioural consistency is an important aspect of software engineering. In process and service management, consistency verification of behavioural models has manifold applications. For instance, a business process model used as system specification and a corresponding workflow model used as implementation have to be consistent. Another example would be the analysis to what degree a process log of executed business operations is consistent with the corresponding normative process model. Typically, existing notions of behaviour equivalence, such as bisimulation and trace equivalence, are applied as consistency notions. Still, these notions are exponential in computation and yield a Boolean result. In many cases, however, a quantification of behavioural deviation is needed along with concepts to isolate the source of deviation. In this article, we propose causal behavioural profiles as the basis for a consistency notion. These profiles capture essential behavioural information, such as order, exclusiveness, and causality between pairs of activities of a process model. Consistency based on these profiles is weaker than trace equivalence, but can be computed efficiently for a broad class of models. In this article, we introduce techniques for the computation of causal behavioural profiles using structural decomposition techniques for sound free-choice workflow systems if unstructured net fragments are acyclic or can be traced back to S- or T-nets. We also elaborate on the findings of applying our technique to three industry model collections.
Resumo:
This paper reports on the results of using unbleached sugar cane bagasse nanofibres (average diameter 26.5 nm; aspect ratio 247 assuming a dry fibre density of 1,500 kg/m3) to improve the physico-chemical properties of starch-based films. The addition of bagasse nanofibres (2.5 to 20 wt%) to modified potato starch (i.e. soluble starch) reduced the moisture uptake by up to 17 % at 58 % relative humidity. The film’s tensile strength and Young’s modulus increased by up to 100 % (3.1 to 6.2 MPa) and 300 % (66.3 to 198.3 MPa) respectively with 10 and 20 wt% fibre addition. However, the strain at yield dropped by 50 % for the film containing 10 wt% fibre. Models for composite materials were used to account for the strong interactions between the nanofibres and the starch matrix. The storage and loss moduli as well as the glass transition temperature (Tg) obtained from dynamic mechanical thermal analysis, were increased with the starch-nanofibre films indicating decreased starch chain mobility due to the interacting effect of the nanofibres. Evidence of the existence of strong interactions between the starch matrix and the nanofibres was revealed from detailed Fourier transform infra-red and scanning electron microscopic evaluation.
Resumo:
The ethical governance of biomedical research is an area of intense international debate. Scholars argue about who should regulate and how, the appropriate role for ethics committees, what kind of research should be included, and who should be involved in monitoring compliance. A particular aspect of these debates concerns the inclusion of women as research participants and the efforts to ensure that researchers consistently investigate questions of sex and gender in health research. There is increasing evidence of the role of sex in the manifestation and course of some illnesses and their treatment. Moreover, evidence suggests that gendered expectations also affect health outcomes. This special issue investigates how researchers are addressing these issues and debates the appropriate roles of policy makers, ethicists, and lawyers in ensuring that sex and gender differences are taken into account in the development, conduct, and reporting of health research.