75 resultados para crystal and ligand fields


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Law has been a close partner to sociology from its very beginning, and the partnership often has proven to be extremely prolific for sociology. Grand theories as well as vital conceptual tools can be counted among its offspring. Both disciplines share the common ground of socio-legal studies, which has developed into a nearly independent interdisciplinary enterprise where legal scholars and sociologists happily meander between the normative and the analytical. From the vast array of topics in the field of socio-legal studies I select the sociology of criminal justice and punishment in order to demonstrate the characteristics of this relationship. The partnership between sociology and law emerged as part of the modernization project in the 19th and 20th centuries, and the sociology of punishment was part of this endeavour. Rooted in a strong tradition of old (Durkheim) and new (Elias, Foucault) classics, recent developments in this field are leaving the idea of an `unproblematically modern punishment' (Whitman, 2005a) behind, and new fields of inquiry for comparative lawyers and sociologists are opening up.

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Young people seen as ‘at risk’ are a substantial focus across a wide range of policy and practice fields in national and international contexts. This article addresses two of those fields, youth homelessness and youth failing to obtain a basic education that will give them access to employment and full community participation as active citizens. By comparing solutions to the problems of youth homelessness and youth educationally at risk, the article distils key meta-characteristics useful for both social workers and educators in mutually supporting some of the most at risk young people in our communities today. This is what the authors term ‘a joined-up practice’.

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The E&P sector can learn much about asset maintenance from the space and satellite industry. Practitioners from both the upstream oil and gas industry and the space and satellite sector have repeatedly noted several striking similarities between the two industries over the years, which have in turn resulted in many direct comparisons in the media and industry press. The similarities between the two industries have even resulted in a modest amount of cross-pollinating between the respective supply chains. Because the operating conditions of both industries are so extreme, some oil and gas equipment vendors have occasionally sourced motors and other parts from aerospace contractors. Also, satellites are now being used to assess oil fires, detect subsidence in oil fields, measure oil spills, collect and transmit operational data from oil and gas fields, and monitor the movement of icebergs that might potentially collide with offshore oil and gas installations.

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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.

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This study examined the prevalence of co-morbid age-related eye disease and symptoms of depression and anxiety in late life, and the relative roles of visual function and disease in explaining symptoms of depression and anxiety. A community-based sample of 662 individuals aged over 70 years was recruited through the electoral roll. Vision was measured using a battery of tests including high and low contrast visual acuity, contrast sensitivity, motion sensitivity, stereoacuity, Useful Field of View, and visual fields. Depression and anxiety symptoms were measured using the Goldberg scales. The prevalence of self-reported eye disease [cataract, glaucoma, or age-related macular degeneration (AMD)] in the sample was 43.4%, with 7.7% reporting more than one form of ocular pathology. Of those with no eye disease, 3.7% had clinically significant depressive symptoms. This rate was 6.7% among cataract patients, 4.3% among those with glaucoma, and 10.5% for AMD. Generalized linear models adjusting for demographics, general health, treatment, and disability examined self-reported eye disease and visual function as correlates of depression and anxiety. Depressive symptoms were associated with cataract only, AMD, comorbid eye diseases and reduced low contrast visual acuity. Anxiety was significantly associated with self-reported cataract, and reduced low contrast visual acuity, motion sensitivity and contrast sensitivity. We found no evidence for elevated rates of depressive or anxiety symptoms associated with self-reported glaucoma. The results support previous findings of high rates of depression and anxiety in cataract and AMD, and in addition show that mood and anxiety are associated with objective measures of visual function independently of self-reported eye disease. The findings have implications for the assessment and treatment of mental health in the context of late-life visual impairment...

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The occurrence of extreme water levels along low-lying, highly populated and/or developed coastlines can lead to considerable loss of life and billions of dollars of damage to coastal infrastructure. Therefore it is vitally important that the exceedance probabilities of extreme water levels are accurately evaluated to inform risk-based flood management, engineering and future land-use planning. This ensures the risk of catastrophic structural failures due to under-design or expensive wastes due to over-design are minimised. This paper estimates for the first time present day extreme water level exceedence probabilities around the whole coastline of Australia. A high-resolution depth averaged hydrodynamic model has been configured for the Australian continental shelf region and has been forced with tidal levels from a global tidal model and meteorological fields from a global reanalysis to generate a 61-year hindcast of water levels. Output from this model has been successfully validated against measurements from 30 tide gauge sites. At each numeric coastal grid point, extreme value distributions have been fitted to the derived time series of annual maxima and the several largest water levels each year to estimate exceedence probabilities. This provides a reliable estimate of water level probabilities around southern Australia; a region mainly impacted by extra-tropical cyclones. However, as the meteorological forcing used only weakly includes the effects of tropical cyclones, extreme water level probabilities are underestimated around the western, northern and north-eastern Australian coastline. In a companion paper we build on the work presented here and more accurately include tropical cyclone-induced surges in the estimation of extreme water level. The multi-decadal hindcast generated here has been used primarily to estimate extreme water level exceedance probabilities but could be used more widely in the future for a variety of other research and practical applications.

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Parameters of a discharge sustained in a planar magnetron configuration with crossed electric and magnetic fields are studied experimentally and numerically. By comparing the data obtained in the experiment with the results of calculations made using the proposed theoretical model, conclusion was made about the leading role of the turbulence-driven Bohm electron conductivity in the low-pressure operation mode (up to 1 Pa) of the discharge in crossed electric and magnetic fields. A strong dependence of the width of the cathode sputter trench, associated with the ionization region of the magnetron discharge, on the discharge parameters was observed in the experiments. The experimental data were used as input parameters in the discharge model that describes the motion of secondary electrons across the magnetic field in the ionization region and takes into account the classical, near-wall, and Bohm mechanisms of electron conductivity.

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Monitoring gases for environmental, industrial and agricultural fields is a demanding task that requires long periods of observation, large quantity of sensors, data management, high temporal and spatial resolution, long term stability, recalibration procedures, computational resources, and energy availability. Wireless Sensor Networks (WSNs) and Unmanned Aerial Vehicles (UAVs) are currently representing the best alternative to monitor large, remote, and difficult access areas, as these technologies have the possibility of carrying specialised gas sensing systems, and offer the possibility of geo-located and time stamp samples. However, these technologies are not fully functional for scientific and commercial applications as their development and availability is limited by a number of factors: the cost of sensors required to cover large areas, their stability over long periods, their power consumption, and the weight of the system to be used on small UAVs. Energy availability is a serious challenge when WSN are deployed in remote areas with difficult access to the grid, while small UAVs are limited by the energy in their reservoir tank or batteries. Another important challenge is the management of data produced by the sensor nodes, requiring large amount of resources to be stored, analysed and displayed after long periods of operation. In response to these challenges, this research proposes the following solutions aiming to improve the availability and development of these technologies for gas sensing monitoring: first, the integration of WSNs and UAVs for environmental gas sensing in order to monitor large volumes at ground and aerial levels with a minimum of sensor nodes for an effective 3D monitoring; second, the use of solar energy as a main power source to allow continuous monitoring; and lastly, the creation of a data management platform to store, analyse and share the information with operators and external users. The principal outcomes of this research are the creation of a gas sensing system suitable for monitoring any kind of gas, which has been installed and tested on CH4 and CO2 in a sensor network (WSN) and on a UAV. The use of the same gas sensing system in a WSN and a UAV reduces significantly the complexity and cost of the application as it allows: a) the standardisation of the signal acquisition and data processing, thereby reducing the required computational resources; b) the standardisation of calibration and operational procedures, reducing systematic errors and complexity; c) the reduction of the weight and energy consumption, leading to an improved power management and weight balance in the case of UAVs; d) the simplification of the sensor node architecture, which is easily replicated in all the nodes. I evaluated two different sensor modules by laboratory, bench, and field tests: a non-dispersive infrared module (NDIR) and a metal-oxide resistive nano-sensor module (MOX nano-sensor). The tests revealed advantages and disadvantages of the two modules when used for static nodes at the ground level and mobile nodes on-board a UAV. Commercial NDIR modules for CO2 have been successfully tested and evaluated in the WSN and on board of the UAV. Their advantage is the precision and stability, but their application is limited to a few gases. The advantages of the MOX nano-sensors are the small size, low weight, low power consumption and their sensitivity to a broad range of gases. However, selectivity is still a concern that needs to be addressed with further studies. An electronic board to interface sensors in a large range of resistivity was successfully designed, created and adapted to operate on ground nodes and on-board UAV. The WSN and UAV created were powered with solar energy in order to facilitate outdoor deployment, data collection and continuous monitoring over large and remote volumes. The gas sensing, solar power, transmission and data management systems of the WSN and UAV were fully evaluated by laboratory, bench and field testing. The methodology created to design, developed, integrate and test these systems was extensively described and experimentally validated. The sampling and transmission capabilities of the WSN and UAV were successfully tested in an emulated mission involving the detection and measurement of CO2 concentrations in a field coming from a contaminant source; the data collected during the mission was transmitted in real time to a central node for data analysis and 3D mapping of the target gas. The major outcome of this research is the accomplishment of the first flight mission, never reported before in the literature, of a solar powered UAV equipped with a CO2 sensing system in conjunction with a network of ground sensor nodes for an effective 3D monitoring of the target gas. A data management platform was created using an external internet server, which manages, stores, and shares the data collected in two web pages, showing statistics and static graph images for internal and external users as requested. The system was bench tested with real data produced by the sensor nodes and the architecture of the platform was widely described and illustrated in order to provide guidance and support on how to replicate the system. In conclusion, the overall results of the project provide guidance on how to create a gas sensing system integrating WSNs and UAVs, how to power the system with solar energy and manage the data produced by the sensor nodes. This system can be used in a wide range of outdoor applications, especially in agriculture, bushfires, mining studies, zoology, and botanical studies opening the way to an ubiquitous low cost environmental monitoring, which may help to decrease our carbon footprint and to improve the health of the planet.

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The development of offshore oil and gas fields require the placement of different equipment on the sea floor. This is done by deploying the equipment from vessels operating in dynamic positioning on the surface. The deployment operation has different phases, and in higher sea states, it may require wave-load synchronization, when the load is going through the splash zone, and heave compensation when the load is close to the sea floor. In this paper, we analyse the performance of a particular type of hardware operating in a heave compensation mode. We derive a comprehensive model, analyse limits of performance and evaluate a control strategy.

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Purpose We designed a visual field test focused on the field utilized while driving to examine associations between field impairment and motor vehicle collision involvement in 2,000 drivers ≥70 years old. Methods The "driving visual field test" involved measuring light sensitivity for 20 targets in each eye, extending 15° superiorly, 30° inferiorly, 60° temporally and 30° nasally. The target locations were selected on the basis that they fell within the field region utilized when viewing through the windshield of a vehicle or viewing the dashboard while driving. Monocular fields were combined into a binocular field based on the more sensitive point from each eye. Severe impairment in the overall field or a region was defined as average sensitivity in the lowest quartile of sensitivity. At-fault collision involvement for five years prior to enrollment was obtained from state records. Poisson regression was used to calculate crude and adjusted rate ratios examining the association between field impairment and at-fault collision involvement. Results Drivers with severe binocular field impairment in the overall driving visual field had a 40% increased rate of at-fault collision involvement (RR 1.40, 95%CI 1.07-1.83). Impairment in the lower and left fields was associated with elevated collision rates (RR 1.40 95%CI 1.07-1.82 and RR 1.49, 95%CI 1.15-1.92, respectively), whereas impairment in the upper and right field regions was not. Conclusions Results suggest that older drivers with severe impairment in the lower or left region of the driving visual field are more likely to have a history of at-fault collision involvement.

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As a key element in their response to new media forcing transformations in mass media and media use, newspapers have deployed various strategies to not only establish online and mobile products, and develop healthy business plans, but to set out to be dominant portals. Their response to change was the subject of an early investigation by one of the present authors (Keshvani 2000). That was part of a set of short studies inquiring into what impact new software applications and digital convergence might have on journalism practice (Tickle and Keshvani 2000), and also looking for demonstrations of the way that innovations, technologies and protocols then under development might produce a “wireless, streamlined electronic news production process (Tickle and Keshvani 2001).” The newspaper study compared the online products of The Age in Melbourne and the Straits Times in Singapore. It provided an audit of the Singapore and Australia Information and Communications Technology (ICT) climate concentrating on the state of development of carrier networks, as a determining factor in the potential strength of the two services with their respective markets. In the outcome, contrary to initial expectations, the early cable roll-out and extensive ‘wiring’ of the city in Singapore had not produced a level of uptake of Internet services as strong as that achieved in Melbourne by more ad hoc and varied strategies. By interpretation, while news websites and online content were at an early stage of development everywhere, and much the same as one another, no determining structural imbalance existed to separate these leading media participants in Australia and South-east Asia. The present research revisits that situation, by again studying the online editions of the two large newspapers in the original study, and one other, The Courier Mail, (recognising the diversification of types of product in this field, by including it as a representative of Newscorp, now a major participant). The inquiry works through the principle of comparison. It is an exercise in qualitative, empirical research that establishes a comparison between the situation in 2000 as described in the earlier work, and the situation in 2014, after a decade of intense development in digital technology affecting the media industries. It is in that sense a follow-up study on the earlier work, although this time giving emphasis to content and style of the actual products as experienced by their users. It compares the online and print editions of each of these three newspapers; then the three mastheads as print and online entities, among themselves; and finally it compares one against the other two, as representing a South-east Asian model and Australian models. This exercise is accompanied by a review of literature on the developments in ICT affecting media production and media organisations, to establish the changed context. The new study of the online editions is conducted as a systematic appraisal of the first level, or principal screens, of the three publications, over the course of six days (10-15.2.14 inclusive). For this, categories for analysis were made, through conducting a preliminary examination of the products over three days in the week before. That process identified significant elements of media production, such as: variegated sourcing of materials; randomness in the presentation of items; differential production values among media platforms considered, whether text, video or stills images; the occasional repurposing and repackaging of top news stories of the day and the presence of standard news values – once again drawn out of the trial ‘bundle’ of journalistic items. Reduced in this way the online artefacts become comparable with the companion print editions from the same days. The categories devised and then used in the appraisal of the online products have been adapted to print, to give the closest match of sets of variables. This device, to study the two sets of publications on like standards -- essentially production values and news values—has enabled the comparisons to be made. This comparing of the online and print editions of each of the three publications was set up as up the first step in the investigation. In recognition of the nature of the artefacts, as ones that carry very diverse information by subject and level of depth, and involve heavy creative investment in the formulation and presentation of the information; the assessment also includes an open section for interpreting and commenting on main points of comparison. This takes the form of a field for text, for the insertion of notes, in the table employed for summarising the features of each product, for each day. When the sets of comparisons as outlined above are noted, the process then becomes interpretative, guided by the notion of change. In the context of changing media technology and publication processes, what substantive alterations have taken place, in the overall effort of news organisations in the print and online fields since 2001; and in their print and online products separately? Have they diverged or continued along similar lines? The remaining task is to begin to make inferences from that. Will the examination of findings enforce the proposition that a review of the earlier study, and a forensic review of new models, does provide evidence of the character and content of change --especially change in journalistic products and practice? Will it permit an authoritative description on of the essentials of such change in products and practice? Will it permit generalisation, and provide a reliable base for discussion of the implications of change, and future prospects? Preliminary observations suggest a more dynamic and diversified product has been developed in Singapore, well themed, obviously sustained by public commitment and habituation to diversified online and mobile media services. The Australian products suggest a concentrated corporate and journalistic effort and deployment of resources, with a strong market focus, but less settled and ordered, and showing signs of limitations imposed by the delay in establishing a uniform, large broadband network. The scope of the study is limited. It is intended to test, and take advantage of the original study as evidentiary material from the early days of newspaper companies’ experimentation with online formats. Both are small studies. The key opportunity for discovery lies in the ‘time capsule’ factor; the availability of well-gathered and processed information on major newspaper company production, at the threshold of a transformational decade of change in their industry. The comparison stands to identify key changes. It should also be useful as a reference for further inquiries of the same kind that might be made, and for monitoring of the situation in regard to newspaper portals on line, into the future.

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Methods are presented for the preparation, ligand density analysis and use of an affinity adsorbent for the purification of a glutathione S-transferase (GST) fusion protein in packed and expanded bed chromatographic processes. The protein is composed of GST fused to a zinc finger transcription factor (ZnF). Glutathione, the affinity ligand for GST purification, is covalently immobilized to a solid-phase adsorbent (Streamline™). The GST–ZnF fusion protein displays a dissociation constant of 0.6 x10-6 M to glutathione immobilized to Streamline™. Ligand density optimization, fusion protein elution conditions (pH and glutathione concentration) and ligand orientation are briefly discussed.

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Despite over three decades of legislation and initiatives designed to tackle the traditional gender divide in the science, technology and design fields, only a quarter of the registered architects in Australia are women. There are no statistics available for other design disciplines, with little known about why women choose design as a career path and who or what influences this decision. This qualitative research addresses this knowledge gap, through semi-structured in-depth interviews conducted with 19 Australian women who completed an industrial (product) design degree. Thematic analysis revealed three key themes: childhood aptitude and exposure; significant experiences and people; and design as a serendipitous choice. The findings emphasise the importance of early exposure to design as a potential career choice, highlighting the critical role played by parents, teachers, professionals and social networks.

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This chapter considers the legal ramifications of Wikipedia, and other online media, such as the Encyclopedia of Life. Nathaniel Tkacz (2007) has observed: 'Wikipedia is an ideal entry-point from which to approach the shifting character of knowledge in contemporary society.' He observes: 'Scholarship on Wikipedia from computer science, history, philosophy, pedagogy and media studies has moved beyond speculation regarding its considerable potential, to the task of interpreting - and potentially intervening in - the significance of Wikipedia's impact' (Tkacz 2007). After an introduction, Part II considers the evolution and development of Wikipedia, and the legal troubles that have attended it. It also considers the establishment of rival online encyclopedia - such as Citizendium set up by Larry Sanger, the co-founder of Wikipedia; and Knol, the mysterious new project of Google. Part III explores the use of mass, collaborative authorship in the field of science. In particular, it looks at the development of the Encyclopedia of Life, which seeks to document the world's biodiversity. This chapter expresses concern that Wiki-based software had to develop in a largely hostile and inimical legal environment. It contends that copyright law and related fields of intellectual property need to be reformed in order better to accommodate users of copyright material (Rimmer 2007). This chapter makes a number of recommendations. First, there is a need to acknowledge and recognize forms of mass, collaborative production and consumption - not just individual authorship. Second, the view of a copyright 'work' and other subject matter as a complete and closed piece of cultural production also should be reconceptualised. Third, the defense of fair use should be expanded to accommodate a wide range of amateur, peer-to-peer production activities - not only in the United States, but in other jurisdictions as well. Fourth, the safe harbor protections accorded to Internet intermediaries, such as Wikipedia, should be strengthened. Fifth, there should be a defense in respect of the use of 'orphan works' - especially in cases of large-scale digitization. Sixth, the innovations of open source licensing should be expressly incorporated and entrenched within the formal framework of copyright laws. Finally, courts should craft judicial remedies to take into account concerns about political censorship and freedom of speech.