849 resultados para stress-based forming limit


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Background Providing ongoing family centred support is an integral part of childhood cancer care. For families living in regional and remote areas, opportunities to receive specialist support are limited by the availability of health care professionals and accessibility, which is often reduced due to distance, time, cost and transport. The primary aim of this work is to investigate the cost-effectiveness of videotelephony to support regional and remote families returning home for the first time with a child newly diagnosed with cancer Methods/design We will recruit 162 paediatric oncology patients and their families to a single centre randomised controlled trial. Patients from regional and remote areas, classified by Accessibility/Remoteness Index of Australia (ARIA+) greater than 0.2, will be randomised to a videotelephone support intervention or a usual support control group. Metropolitan families (ARIA+ ≤ 0.2) will be recruited as an additional usual support control group. Families allocated to the videotelephone support intervention will have access to usual support plus education, communication, counselling and monitoring with specialist multidisciplinary team members via a videotelephone service for a 12-week period following first discharge home. Families in the usual support control group will receive standard care i.e., specialist multidisciplinary team members provide support either face-to-face during inpatient stays, outpatient clinic visits or home visits, or via telephone for families who live far away from the hospital. The primary outcome measure is parental health related quality of life as measured using the Medical Outcome Survey (MOS) Short Form SF-12 measured at baseline, 4 weeks, 8 weeks and 12 weeks. The secondary outcome measures are: parental informational and emotional support; parental perceived stress, parent reported patient quality of life and parent reported sibling quality of life, parental satisfaction with care, cost of providing improved support, health care utilisation and financial burden for families. Discussion This investigation will establish the feasibility, acceptability and cost-effectiveness of using videotelephony to improve the clinical and psychosocial support provided to regional and remote paediatric oncology patients and their families.

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Data preprocessing is widely recognized as an important stage in anomaly detection. This paper reviews the data preprocessing techniques used by anomaly-based network intrusion detection systems (NIDS), concentrating on which aspects of the network traffic are analyzed, and what feature construction and selection methods have been used. Motivation for the paper comes from the large impact data preprocessing has on the accuracy and capability of anomaly-based NIDS. The review finds that many NIDS limit their view of network traffic to the TCP/IP packet headers. Time-based statistics can be derived from these headers to detect network scans, network worm behavior, and denial of service attacks. A number of other NIDS perform deeper inspection of request packets to detect attacks against network services and network applications. More recent approaches analyze full service responses to detect attacks targeting clients. The review covers a wide range of NIDS, highlighting which classes of attack are detectable by each of these approaches. Data preprocessing is found to predominantly rely on expert domain knowledge for identifying the most relevant parts of network traffic and for constructing the initial candidate set of traffic features. On the other hand, automated methods have been widely used for feature extraction to reduce data dimensionality, and feature selection to find the most relevant subset of features from this candidate set. The review shows a trend toward deeper packet inspection to construct more relevant features through targeted content parsing. These context sensitive features are required to detect current attacks.

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Whether the community is looking for “scapegoats” to blame, or seeking more radical and deeper causes, health care managers are in the firing line whenever there are woes in the health care sector. The public has a right to question whether ethics have much influence on the everyday decision making of health care managers. This thesis explores, through a series of published papers, the influence of ethics and other factors on the decision making of health care managers in Australia. Critical review of over 40 years of research on ethical decision making has revealed a large number of influencing factors, but there is a demonstrable lack of a multidimensional approach that measures the combined influences of these factors on managers. This thesis has developed an instrument, the Managerial Ethical Profile (MEP) scale, based on a multidimensional model combining a large number of influencing factors. The MEP scale measures the range of influences on individual managers, and describes the major tendencies by developing a number of empirical profiles derived from a hierarchical cluster analysis. The instrument was developed and refined through a process of pilot studies on academics and students (n=41) and small-business managers (n=41), and then was administered to the larger sample of health care managers (n=441). Results from this study indicate that Australian health care managers draw on a range of ethical frameworks in their everyday decision making, forming the basis of five MEPs (Knights, Guardian Angels, Duty Followers, Defenders, and Chameleons). Results from the study also indicate that the range of individual, organisational, and external factors that influence decision making can be grouped into three major clusters or functions. Cross referencing these functions and other demographic data to the MEPs provides analytical insight into the characteristics of the MEPs. These five profiles summarise existing strengths and weaknesses in managerial ethical decision making. Therefore identifying these profiles not only can contribute to increasing organisational knowledge and self-awareness, but also has clear implications for the design and implementation of ethics education and training in large scale organisations in the health care industry.

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This paper is the second in a series of reviews of cross-cultural studies of menopausal symptoms. The goal of this review is to compare and contrast methods which have been previously utilized in Cross-Cultural Midlife Women's Health Studies with a view to (1) identifying the challenges in measurement across cultures in psychological symptoms and (2) suggesting a set of unified questions and tools that can be used in future research in this area. This review also aims to examine the determinants of psychological symptoms and how those determinants were measured. The review included eight studies that explicitly compared symptoms in different countries or different ethnic groups in the same country and included: Australian/Japanese Midlife Women's Health Study (AJMWHS), Decisions At Menopause Study (DAMeS), Four Major Ethnic Groups (FMEG), Hilo Women's Health Survey (HWHS), Penn Ovarian Aging Study (POAS), Study of Women's Health Across the Nation (SWAN), Women's Health in Midlife National Study (WHiMNS), and the Women's International Study of Health and Sexuality (WISHeS). This review concludes that mental morbidity does affect vasomotor symptom prevalence across cultures and therefore should be measured. Based on the review of these eight studies it is recommended that the following items be included when measuring psychological symptoms across cultures, feeling tense or nervous, sleeping difficulty, difficulty in concentrating, depressed and irritability along with the CES-D Scale, and the Perceived Stress Scale. The measurement of these symptoms will provide an evidence based approach when forming any future menopause symptom list and allow for comparisons across studies.

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Demands for delivering high instantaneous power in a compressed form (pulse shape) have widely increased during recent decades. The flexible shapes with variable pulse specifications offered by pulsed power have made it a practical and effective supply method for an extensive range of applications. In particular, the release of basic subatomic particles (i.e. electron, proton and neutron) in an atom (ionization process) and the synthesizing of molecules to form ions or other molecules are among those reactions that necessitate large amount of instantaneous power. In addition to the decomposition process, there have recently been requests for pulsed power in other areas such as in the combination of molecules (i.e. fusion, material joining), gessoes radiations (i.e. electron beams, laser, and radar), explosions (i.e. concrete recycling), wastewater, exhausted gas, and material surface treatments. These pulses are widely employed in the silent discharge process in all types of materials (including gas, fluid and solid); in some cases, to form the plasma and consequently accelerate the associated process. Due to this fast growing demand for pulsed power in industrial and environmental applications, the exigency of having more efficient and flexible pulse modulators is now receiving greater consideration. Sensitive applications, such as plasma fusion and laser guns also require more precisely produced repetitive pulses with a higher quality. Many research studies are being conducted in different areas that need a flexible pulse modulator to vary pulse features to investigate the influence of these variations on the application. In addition, there is the need to prevent the waste of a considerable amount of energy caused by the arc phenomena that frequently occur after the plasma process. The control over power flow during the supply process is a critical skill that enables the pulse supply to halt the supply process at any stage. Different pulse modulators which utilise different accumulation techniques including Marx Generators (MG), Magnetic Pulse Compressors (MPC), Pulse Forming Networks (PFN) and Multistage Blumlein Lines (MBL) are currently employed to supply a wide range of applications. Gas/Magnetic switching technologies (such as spark gap and hydrogen thyratron) have conventionally been used as switching devices in pulse modulator structures because of their high voltage ratings and considerably low rising times. However, they also suffer from serious drawbacks such as, their low efficiency, reliability and repetition rate, and also their short life span. Being bulky, heavy and expensive are the other disadvantages associated with these devices. Recently developed solid-state switching technology is an appropriate substitution for these switching devices due to the benefits they bring to the pulse supplies. Besides being compact, efficient, reasonable and reliable, and having a long life span, their high frequency switching skill allows repetitive operation of pulsed power supply. The main concerns in using solid-state transistors are the voltage rating and the rising time of available switches that, in some cases, cannot satisfy the application’s requirements. However, there are several power electronics configurations and techniques that make solid-state utilisation feasible for high voltage pulse generation. Therefore, the design and development of novel methods and topologies with higher efficiency and flexibility for pulsed power generators have been considered as the main scope of this research work. This aim is pursued through several innovative proposals that can be classified under the following two principal objectives. • To innovate and develop novel solid-state based topologies for pulsed power generation • To improve available technologies that have the potential to accommodate solid-state technology by revising, reconfiguring and adjusting their structure and control algorithms. The quest to distinguish novel topologies for a proper pulsed power production was begun with a deep and through review of conventional pulse generators and useful power electronics topologies. As a result of this study, it appears that efficiency and flexibility are the most significant demands of plasma applications that have not been met by state-of-the-art methods. Many solid-state based configurations were considered and simulated in order to evaluate their potential to be utilised in the pulsed power area. Parts of this literature review are documented in Chapter 1 of this thesis. Current source topologies demonstrate valuable advantages in supplying the loads with capacitive characteristics such as plasma applications. To investigate the influence of switching transients associated with solid-state devices on rise time of pulses, simulation based studies have been undertaken. A variable current source is considered to pump different current levels to a capacitive load, and it was evident that dissimilar dv/dts are produced at the output. Thereby, transient effects on pulse rising time are denied regarding the evidence acquired from this examination. A detailed report of this study is given in Chapter 6 of this thesis. This study inspired the design of a solid-state based topology that take advantage of both current and voltage sources. A series of switch-resistor-capacitor units at the output splits the produced voltage to lower levels, so it can be shared by the switches. A smart but complicated switching strategy is also designed to discharge the residual energy after each supply cycle. To prevent reverse power flow and to reduce the complexity of the control algorithm in this system, the resistors in common paths of units are substituted with diode rectifiers (switch-diode-capacitor). This modification not only gives the feasibility of stopping the load supply process to the supplier at any stage (and consequently saving energy), but also enables the converter to operate in a two-stroke mode with asymmetrical capacitors. The components’ determination and exchanging energy calculations are accomplished with respect to application specifications and demands. Both topologies were simply modelled and simulation studies have been carried out with the simplified models. Experimental assessments were also executed on implemented hardware and the approaches verified the initial analysis. Reports on details of both converters are thoroughly discussed in Chapters 2 and 3 of the thesis. Conventional MGs have been recently modified to use solid-state transistors (i.e. Insulated gate bipolar transistors) instead of magnetic/gas switching devices. Resistive insulators previously used in their structures are substituted by diode rectifiers to adjust MGs for a proper voltage sharing. However, despite utilizing solid-state technology in MGs configurations, further design and control amendments can still be made to achieve an improved performance with fewer components. Considering a number of charging techniques, resonant phenomenon is adopted in a proposal to charge the capacitors. In addition to charging the capacitors at twice the input voltage, triggering switches at the moment at which the conducted current through switches is zero significantly reduces the switching losses. Another configuration is also introduced in this research for Marx topology based on commutation circuits that use a current source to charge the capacitors. According to this design, diode-capacitor units, each including two Marx stages, are connected in cascade through solid-state devices and aggregate the voltages across the capacitors to produce a high voltage pulse. The polarity of voltage across one capacitor in each unit is reversed in an intermediate mode by connecting the commutation circuit to the capacitor. The insulation of input side from load side is provided in this topology by disconnecting the load from the current source during the supply process. Furthermore, the number of required fast switching devices in both designs is reduced to half of the number used in a conventional MG; they are replaced with slower switches (such as Thyristors) that need simpler driving modules. In addition, the contributing switches in discharging paths are decreased to half; this decrease leads to a reduction in conduction losses. Associated models are simulated, and hardware tests are performed to verify the validity of proposed topologies. Chapters 4, 5 and 7 of the thesis present all relevant analysis and approaches according to these topologies.

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Road dust contain potentially toxic pollutants originating from a range of anthropogenic sources common to urban land uses and soil inputs from surrounding areas. The research study analysed the mineralogy and morphology of dust samples from road surfaces from different land uses and background soil samples to characterise the relative source contributions to road dust. The road dust consist primarily of soil derived minerals (60%) with quartz averaging 40-50% and remainder being clay forming minerals of albite, microcline, chlorite and muscovite originating from surrounding soils. About 2% was organic matter primarily originating from plant matter. Potentially toxic pollutants represented about 30% of the build-up. These pollutants consist of brake and tire wear, combustion emissions and fly ash from asphalt. Heavy metals such as Zn, Cu, Pb, Ni, Cr and Cd primarily originate from vehicular traffic while Fe, Al and Mn primarily originate from surrounding soils. The research study confirmed the significant contribution of vehicular traffic to dust deposited on urban road surfaces.

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The LiteSteel Beam (LSB) is a new cold-formed hollow flange channel section developed by OneSteel Australian Tube Mills using their patented dual electric resistance welding and automated continuous roll-forming process. It has a unique geometry consisting of torsionally rigid rectangular hollow flanges and a relatively slender web. In addition to this unique geometry, the LSB sections also have unique characteristics relating to their stress-strain curves, residual stresses, initial geometric imperfections and hollow flanges that are not encountered in conventional hot-rolled and cold-formed steel channel sections. An experimental study including 20 section moment capacity tests was therefore conducted to investigate the behaviour and strength of LSB flexural members. The presence of inelastic reserve bending capacity in these beams was investigated in detail although the current design rules generally limit the section moment capacities of cold-formed steel members to their first yield moments. The ultimate moment capacities from the tests were compared with the section moment capacities predicted by the current cold-formed and hot-rolled steel design standards. It was found that compact and non-compact LSB sections have greater moment capacities than their first yield moments. The current cold-formed steel design standards were found to be conservative in predicting the section moment capacities of compact and non-compact LSB sections while the hot-rolled steel design standards were able to better predict them. This paper has shown that suitable modifications are needed to the current design rules to allow the inclusion of available inelastic bending capacities of LSBs in design.

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The Western Downs region, located in Southern Queensland, about 200 kilometres west of Brisbane, has been experiencing rapid and significant changes over the past years, due to a massive boom in the energy sector. The rapid growth triggered by the development of mining and energy sectors has generated environmental, socio-economic and land use issues, and has revealed strong weaknesses within the region’s current governance arrangements. The present paper develops a four-stage approach to managing current and expected changes in a resource-based region under tremendous stress and uncertainty.

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The silence of objects phenomenologically explores the experience and memory of trauma through object-based artwork. It springs from a desire to map difficult psychological terrain and does so by tracking the process of a coming into 'expression' to communicate notions of loss, detachment and powerlessness. It maps a journey from silence to a forming 'voice' that gives shape to the unsayable. This practice-led research is multifaceted. Whilst the creative element uses transformed objects as material metaphors to tap into the sensory and affective operations of art, the written component blends reflection with theory and is informed by art theorists Jill Bennett and Mignon Nixon. By establishing a dialogue between theoretical constructs and creative works I consider how giving form to deep consciousness can counter the effects of trauma manifest as silence and invisibility.

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Academic pressure among adolescents is a major risk factor for poor mental health and suicide and other harmful behaviours. While this is a worldwide phenomenon, it appears to be especially pronounced in China and other East Asian countries. Despite a growing body of research into adolescent mental health in recent years, the multiple constructs within the ‘educational stress’ phenomenon have not been clearly articulated in Chinese contexts. Further, the individual, family, school and peer influencing factors for educational stress and its associations with adolescent mental health are not well understood. An in-depth investigation may provide important information for the ongoing educational reform in Mainland China with a special focus on students’ mental health and wellbeing. The primary goal of this study was to examine the relative contribution of educational stress to poor mental health, in comparison to other well-known individual, family, school and peer factors. Another important task was to identify significant risk factors for educational stress. In addition, due to the lack of a culturally suitable instrument for educational stress in this population, a new tool – the Educational Stress Scale for Adolescents (ESSA) was initially developed in this study and tested for reliability and validity. A self-administered questionnaire was used to collect information from convenient samples of secondary school students in Shandong, China. The pilot survey was conducted with 347 students (grades 8 and 11) to test the psychometric properties of the ESSA and other scales or questions in the questionnaire. Based on factor analysis and reliability and validity testing, the 16-item scale (the ESSA) with five factors showed adequate to good internal consistency, 2-week test-retest reliability, and satisfactory concurrent and predictive validity. Its factor structure was further demonstrated in the main survey with a confirmatory factor analysis illustrating a good fit of the proposed model based on a confirmatory factor analysis. The reliabilities of other scales and questions were also adequate to be used in this study. The main survey was subsequently conducted with a sample of 1627 secondary school (grades 7-12) students to examine the influencing factors of educational stress and its associations with mental health outcomes, including depression, happiness and suicidal behaviours. A wide range of individual, family, school and peer factors were found to have a significant association with the total ESSA and subscale scores. Most of the strong factors for academic stress were school or study-related, including rural school location, low school connectedness, perceived poor academic grades and frequent emotional conflicts with teachers and peers. Unexpectedly, family and parental factors, such as parental bonding, family connectedness and conflicts with parents were found to have little or no association with educational stress. Educational stress was the most predictive variable for depression, but was not strongly associated with happiness. It had a strong association with suicide ideation but not with suicide attempts. Among five subscales of the ESSA, ‘Study despondency’ score had the strongest associations with these mental health measures. Surprising, two subscales, ‘Self-expectation’ and ‘Worry about grades’ showed a protective effect on suicidal behaviours. An additional analysis revealed that although academic pressure was the most commonly reported reason for suicidal thinking, the occurrence of problems in peer relationships such as peer teasing and bullying, and romantic problems had a much stronger relationship with actual attempts. This study provides some insights into the nature and health implications of educational stress among Chinese adolescents. Findings in this study suggest that interventions on educational stress should focus on school environment and academic factors. Intervention programs focused on educational stress may have a high impact on the prevalence of common mental disorders such as depression. Efforts to increase perceived happiness however should cover a wider range of individual, family and school factors. The importance of healthy peer relationships should be adequately emphasised in suicide prevention. In addition, the newly developed scale (the ESSA) demonstrates sound psychometric properties and is expected to be used in future research into academic-related stress among secondary school adolescents.

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The present research examined the effects of occupational stress in psychiatric nursing on employee well!being using the full Job Strain Model.The Job Strain Model was assessed for its ability to predict employee well!being in terms of job satisfaction and mental health. The original Job Strain Model was expanded to include social support based on previous research concerning the impact of social support on well!being[ In the present study\ both work support and non-work were assessed for their contribution to wellbeing.The results of this study indicate that the full Job Strain Model can be used to significantly predict job satisfaction and mental health in this sample of Australian psychiatric nurses. Furthermore social support was shown to be an important component of the Job Strain Model.

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Based on the eigen crack opening displacement (COD) boundary integral equations, a newly developed computational approach is proposed for the analysis of multiple crack problems. The eigen COD particularly refers to a crack in an infinite domain under fictitious traction acting on the crack surface. With the concept of eigen COD, the multiple cracks in great number can be solved by using the conventional displacement discontinuity boundary integral equations in an iterative fashion with a small size of system matrix. The interactions among cracks are dealt with by two parts according to the distances of cracks to the current crack. The strong effects of cracks in adjacent group are treated with the aid of the local Eshelby matrix derived from the traction BIEs in discrete form. While the relatively week effects of cracks in far-field group are treated in the iteration procedures. Numerical examples are provided for the stress intensity factors of multiple cracks, up to several thousands in number, with the proposed approach. By comparing with the analytical solutions in the literature as well as solutions of the dual boundary integral equations, the effectiveness and the efficiencies of the proposed approach are verified.

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This study investigated the effect of a fear-based personality trait, as conceptualised in Gray’s revised reinforcement sensitivity theory (RST) by the strength of the fight/flight/freeze system (FFFS), on young people’s driving simulator performance under induced psychosocial stress. Seventy-one young drivers completed the Jackson-5 questionnaire of RST traits, followed by a psychosocial stress or relaxation induction procedure (random allocation to groups) and then a city driving simulator task. Some support was found for the hypothesis that higher FFFS sensitivity would result in poorer driving performance under stress, in terms of significantly poorer hazard responses, possibly due to an increased attentional focus on the aversive cues inherent in the stress induction leaving reduced attentional capacity for the driving task. These results suggest that stress may lead to riskier driving behaviour in individuals with fearful RST personality styles.

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Sequencing of mba gene fragments of reference strains of Ureaplasma urealyticum serovars 1, 3, 6, 14, in addition to 33 clinical U. urealyticum isolates is reported. A phylogenetic tree deduced from an alignment of these sequences clearly demonstrates two major clusters (confidence limit 100%), which equate to the parvo and T960 biovars, and five types which we have designated mba 1, 3, 6, 8 and X. These relationships are supported by bootstrap analysis. Polymorphisms within the mba fragment of types mba 1, 3, and 6 were used to define nine subtypes (mba 1a, 1b, 3a, 3b, 3c, 3d, 3e, 6a, and 6b) thus facilitating high resolution typing of U. urealyticum. Inclusion of the reference strains for serovars 1, 3, 6, and 8 in the mba typing scheme showed that the results of this analysis are broadly consistent with currently accepted serotyping. In addition a ure gene fragment from nine of the clinical isolates was amplified and sequenced. Comparisons of the sequences clearly distinguished the two biovars of U. urealyticum; however this fragment was invariant within the parvo biovar. This study has shown that the sequence of the mba can reveal the fine details of the relationships between U. urealyticum isolates and also supports the significant evolutionary gap between the two biovars.