130 resultados para Stress-based forming limit


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Background : The diagnosis and treatment of cancer is a major life stress such that approximately 35% of patients experience persistent clinically significant distress and carers often experience even higher distress than patients. This paper presents the design of a two arm randomised controlled trial with patients and carers who have elevated psychological distress comparing minimal contact self management vs. an individualised tele-based cognitive behavioural intervention.

Methods/design :
140 patients and 140 carers per condition (560 participants in total) will been recruited after being identified as high distress through caller screening at two community-based cancer helplines and randomised to 1) a single 30-minute telephone support and education session with a nurse counsellor with self management materials 2) a tele-based psychologist delivered five session individualised cognitive behavioural intervention. Session components will include stress reduction, problem-solving, cognitive challenging and enhancing relationship support and will be delivered weekly. Participants will be assessed at baseline and 3, 6 and 12 months after recruitment. Outcome measures include: anxiety and depression, cancer specific distress, unmet psychological supportive care needs, positive adjustment, overall Quality of life.

Discussion :
The study will provide recommendations about the efficacy and potential economic value of minimal contact self management vs. tele-based psychologist delivered cognitive behavioural intervention to facilitate better psychosocial adjustment and mental health for people with cancer and their carers.

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Purpose – The overall purpose of this paper is to examine the extent to which breaches in psychological contracts and perceptions of organizational fairness account for variations in job stress experienced by operational police officers (as measured by psychological distress and employee performance), after controlling for the variance associated with more established job stressors (i.e. job demands, job control and social support).

Design/methodology/approach – This study is based on data collected through a self-report survey involving operational members of a large Australian police force (n=582).

Findings – Results of hierarchical multiple regression analyses indicate that vast majority of explained variance in psychological distress and extra-role performance is attributed to the additive effects of demand, control, and support. Furthermore, only one of the social exchange dimensions (interpersonal fairness) is predictive of either target variable.

Research limitations/implications – The limitations that need to be taken into account are the cross-sectional nature of the study design and the focus on a single police service.

Practical implications – Despite the generally weak support for the social exchange variables, there are signs that dimensions of justice (particularly interpersonal justice) should be included in future police-stress investigations. The results also suggest that job characteristics such as job demand, job control and social support should be taken into account when developing strategies to prevent and/or reduce chronic job stress in policing services.

Originality/value – This is one of the first studies to examine the relationships between psychological contract breach, perceptions of fairness and police stress.

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The term “post-traumatic stress disorder” (PTSD) is a relatively new diagnostic label, being formally recognized in 1980 in the Diagnostic Statistical Manual for Psychiatric Illness – Third Edition (DSM-III) of the American Psychiatric Association (APA, 1980). Complex Post-Traumatic Stress Disorder (CP) is a more recently discussed, and newly-classified, phenomenon, initially discussed in the early 1990s (Herman, 1992a). Thus, as research into effective treatments for CP is sparse, the treatment of CP is the topic of this study, in which a guideline-based treatment program developed by the researcher for the treatment of CP is implemented and evaluated. Ten individuals participated in this study, undertaking individualized, guideline-based treatment programs spanning a period of six months. In providing background information relevant to this study, an explanation is provided regarding the nature of CP, and the reasons for its consideration as a separate phenomenon to PTSD. The adequacy of the PTSD formulation in enabling effective assessment and treatment of CP is also explored, with endorsement of previous researchers’ conclusions that the CP construct is more useful than the PTSD construct for assessing and treating survivors of long-term and multiple forms of abuse. The PTSD classification is restrictive, and not necessarily appropriate for certain forms of trauma (such as prolonged trauma, or multiple forms of trauma), as such trauma experiences may lead to specific effects that lay outside those formerly associated with PTSD. Such effects include alterations in affect regulation, consciousness, self-perception, interpersonal relationships, and in systems of meaning. Following discussion regarding the PTSD/CP classification, an examination of treatment methods currently used in the treatment of PTSD, and a review of treatment outcome studies, takes place. The adequacy of primary treatment methods in treating CP symptoms is then examined, with the conclusion that a range of treatment methods could potentially be useful in the treatment of CP symptoms. Individuals with a diagnosis of CP may benefit from the adoption of an eclectic approach, drawing on different treatment options for different symptoms, and constantly evaluating client progress and re-evaluating interventions. This review of treatment approaches is followed by details of an initial study undertaken to obtain feedback from individuals who had suffered long-term/multiple trauma and who had received treatment. Participants in this initial study were asked open-ended questions regarding the treatment approach they had experienced, the most useful aspect of the treatment, the least useful aspect, and other strategies/treatment approaches that may have been useful – but which were not used. The feedback obtained from these individuals was used to inform the development of treatment guidelines for use in the main study, as were recommendations made by Chu (1998). The predominant focus of the treatment guidelines was “ego strengthening”, a term coined by Chu (1998) to describe the “initial (sometimes lengthy) period of developing fundamental skills in maintaining supportive relationships, developing self-care strategies, coping with symptomatology, improving functioning, and establishing a positive self identity” (p.75). Using a case study approach, data are then presented relating to each of the ten individuals involved in the treatment program: details of his/her trauma experience(s)and the impact of the trauma (as perceived by each individual); details of each individual’s treatment program (as planned, and as implemented); post-treatment evaluation of the positive and negative aspects of the treatment program (from the therapist’s perspective); and details of the symptoms reported by the individual post-treatment, via psychometric assessment and also during interview. Analysis and discussion of the data relating to the ten participants in the study are the focal point of this study. The evaluation of the effectiveness of each individual’s treatment has been based predominantly on qualitative data, obtained from an analysis of language (discourse analysis) used by participants to describe their symptoms pre- and post-treatment. Both blatant and subtle changes in the language used by participants to describe themselves, their behaviour, and their relationships pre- and post-treatment have provided an insight into the possible changes that occurred as a result of the treatment program. The language used by participants has been a rich source of data, one that has enabled the researcher to obtain information that could not be obtained using psychometric assessment methods. Most of the participants in this study portrayed notable changes in many of the CP symptoms, including being more stable and having improved capacity to explore their early abuse. Although no direct cause-effect relationship between the participants’ treatment program and the improvements described can be established from this study, the participants’ perception that the program assisted them with their symptoms, and reported many aspects of “ego strengthening”, is of major importance. Such self-perception of strength and empowerment is important if an individual is going to be able to deal with past trauma experiences. In fact, abreactive work may have a greater chance of succeeding if those who have experienced long-term or multiple trauma are feeling more empowered, and more stable, as were the participants in this study (post-intervention). In concluding this study, recommendations have been made in regard to the use of guideline-based treatment programs in the responsible treatment of CP. Strengths and limitations of this study have also been highlighted, and recommendations have been made regarding possibilities for future research related to CP treatment. On the whole, this study has supported strongly other research that highlights the importance of focusing on “ego strengthening” in assisting those who have suffered long-term/multiple trauma experiences. Thus, a guideline-based program focusing on assisting sufferers of long-term trauma with some, or all, of the symptoms of CP, is recommended as an important first stage of any treatment of individuals who have experienced long-term/multiple trauma, allowing them to develop the emotional and psychological strength required to deal with past traumatic events. Clinicians who are treating patients whose history depicts long-term or multiple trauma experiences (either from their childhood, or at some stage in their adult life) need, therefore, to be mindful of assessing individuals for symptoms of CP – so that they can treat these symptoms prior to engaging in any work associated directly with the past traumatic experiences.

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The effect of carbide precipitates with a size range of 30–300 nm on the austenite to martensite transformation has been studied. Such particles are known to enhance shape memory, and it was the aim of this work to clarify how the particles exert a favourable effect on shape memory. Differential scanning calorimetry revealed that the presence of particles increases the amount of thermally induced martensite. X-ray diffraction showed that the presence of particles increases the amount of stress-induced martensite also. Surface-relief produced on a pre-polished surface by bending deformation showed that the particle-containing samples exhibited a more complex and highly tilted surface-relief indicative of the formation of a larger volume fraction of martensite. The reversion characteristics of the particle-containing and solution-treated samples were similar: both showed co-reversion of multiple variants of martensite within the same volume of microstructure. However, a higher volume fraction of martensite reverted for the particle-containing sample on recovery annealing. The increased density of nucleation sites for martensite formation and a higher volume fraction of stress-induced martensite for a given strain are therefore considered to be the main contributions of relatively coarse carbide particles to the improvement of shape memory performance.

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This study examined the extent to which preparers and end-users of Activity-Based Costing information are satisfied with this technique and the factors forming the basis of that belief.

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A new stress scale was devised based on issues raised by people with an intellectual disability and entitled the Lifestress Inventory. The Inventory was used in a number of studies in order to assess the impact of daily hassles and life events on their perceived stress levels and quality of life. Data suggests that they experience general worries, negative interpersonal relations with others, and frustration with their restricted coping skills as their principal areas of stress.

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Solvent-free polymer electrolytes based on poly(vinyl alcohol) (PVA) and LiCF3SO3 have shown relatively high conductivities (10−8-10−4 S cm−1), with Arrhenius temperature dependence below the differential scanning calorimeter (DSC) glass transition temperature (343 K). This behaviour is in stark contrast to traditional polymer electrolytes in which the conductivity reflects VTF behaviour. 7Li nuclear magnetic resonance (NMR) spectroscopy has been employed to develop a better understanding of the conduction mechanism. Variable temperature NMR has indicated that, unlike traditional polymer electrolytes where the linewidth reaches a rigid lattice limit near Tg, the lithium linewidths show an exponential decrease with increasing temperature between 260 and 360 K. The rigid lattice limit appears to be below 260 K. Consequently, the mechanism for ion conduction appears to be decoupled from the main segmental motions of the PVA. Possible mechanisms include ion hopping, proton conduction or ionic motion assisted by secondary polymer relaxations.

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The bis(trifluoromethanesulfonyl)imide ion has recently been used in its lithium salt as a useful ion in solid polymer electrolytes because of the reduced degree of ion interaction its diffuse charge generates. In this work we have synthesised a number of novel salts based on the ammonium and pyrrolidinium cations of this anion. The salts all show reduced melting points compared with analogous halide salts. In some cases they are molten at room temperature. This latter group of salts have been characterized with respect to their properties as ionic liquids; the highest room temperature conductivity 2 mS cm−1 being exhibited by methyl butyl pyrrolidinium imide. Many of the salts are glass forming, exhibiting glass transition temperatures in the region of −90°C.

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Based on the behaviour of the superplastic deformation of metallic glasses and Pilling’s model, a diffusion bonding model suitable for metallic glasses is proposed in the present study. In the current model, the diffusion bonding processes consists of two stages: one is the plastic deformation stage and the other is the void shrinkage stage, in which, the atom diffusion and superplastic deformation are responsible for the void shrinkage. Applying this model to the diffusion bonding of a Zr based metallic glass, the predicted bonding time is in good agreement with the experimental result. A map for determining the bonding temperature and time to achieve high quality bonding in a Zr based metallic glass is suggested.

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Objective To develop and evaluate the effectiveness of a community behavioural intervention to prevent weight gain and improve health related behaviours in women with young children.
Design Cluster randomised controlled trial.
Setting A community setting in urban Australia. 
Participants 250 adult women with a mean age of 40. 39 years (SD 4.77, range 25-51) and a mean body mass index of 27.82 kg/m2 (SD 5.42, range 18-47) were recruited as clusters through 12 primary (elementary) schools. Intervention Schools were randomly assigned to the intervention or the control. Mothers whose schools fell in the intervention group (n=127) attended four interactive group sessions that involved simple health messages, behaviour change strategies, and group discussion, and received monthly support using mobile telephone text messages for 12 months. The control group (n=123)
attended one non-interactive information session based on population dietary and physical activity guidelines. 
Main outcome measures The main outcome measures were weight change and difference in weight change between the intervention group and the control group at 12 months. Secondary outcomes were changes in serum concentrations of fasting lipids and glucose, and changes in dietary behaviours, physical activity, and self management behaviours.
Results All analyses were adjusted for baseline values and the possible clustering effect. Women in the control group gained weight over the 12 month study period (0.83 kg, 95% confidence interval (CI) 0.12 to 1.54), whereas those in the intervention group lost weight (−0.20 kg, −0.90 to 0.49). The difference in weight change between the intervention group and the control group at 12 months was −1.13 kg (−2.03 to −0.24 kg; P<0.05) on the basis of observed values and −1.11 kg (−2.17 to −0.04) after multiple imputation to account for possible bias created by missing values. Secondary analyses after multiple imputation showed a difference in the intervention group compared with the control group for total cholesterol concentration (−0.35 mmol/l, −0.70 to −0.001), self management behaviours (diet score 0.18, 0.13 to 0.33; physical activity score 0.24, 0.05 to 0.43), and confidence to control weight (0.40, 0.11 to 0.69). Regular self weighing was associated with weight loss in the intervention group only (−1.98 kg, −3.75 to −0.23).
Conclusions Weight gain in women with young children could be prevented using a low intensity self management intervention delivered in a community setting. Self management of health behaviours improved with the intervention. The response rate of 12%, although comparable with that in other community studies, might limit the ability to generalise to other populations.    
Trial registration Australian New Zealand Clinical Trials Registry number ACTRN12608000110381.

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Fucoid algae often dominate intertidal rocky shores, providing habitat and modifying ecosystem resources for other species, but are susceptible to discharge of sewage effluent. In this study we assessed the potential for competition from coralline turfs to inhibit restoration of the intertidal fucoid macroalga Hormosira banksii at sites associated with an ocean outfall a scenario of improving following water quality in the nearshore coastal environment. The percentage cover and number of individuals of H. banksii were negatively correlated with both the percentage cover and turf height of Corallina officinalis. In contrast, H. banksii was positively associated with rocky substrata and recruited well to rock-surface substrata. Importantly, there appears to be a threshold abundance where the percentage cover of H. banksii rarely reaches above 20% cover amongst coralline turfs with >40% cover. These data support a model of alternative community states: H. banksii dominated canopy on rocky substrata versus C. officinalis turf. In field and laboratory experiments, extensive coralline turfs (up to 4 cm thick) were shown to inhibit recruitment of H. banksii. This study shows competitive exclusion by coralline turfs may limit the successful restoration of habitat provided by H. banksii to shores that have been affected by sustained discharge of secondarily treated sewage effluent. We suggest potential strategies for management authorities to consider when seeking ways of restoring fucoid communities affected by anthropogenic disturbances such as wastewater disposal.

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In this paper, we introduce a single-walled boron nitride nanotube (SWBNNT)-based cantilever biosensor, and investigate its bending deformation. The BNNT-based cantilever is modelled by accounting that the surface of the cantilever beam is coated with the antibody molecule. We have considered two main approaches for the mechanical deformation of the BNNT beam. The first one is differential surface stress produced by the binding of biomolecules onto its surface, and the second one is the charge released from the biomolecular interaction. In addition, other parameters including length of beam, variation of beam’s location and chiralities of the BNNT have been taken into consideration to design the cantilever biosensor. The computed results are in good agreement with the well known electrostatic equations that govern the deformation of the cantilever.

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Variation in the incoming sheet material and fluctuations in the press setup is unavoidable in many stamping plants. The effect of these variations can have a large influence on the quality of the final stamping, in particular, unpredictable springback of the sheet when the tooling is removed. While stochastic simulation techniques have been developed to simulate this problem, there has been little research that connects the influence of the noise sources to springback. This paper characterises the effect of material and process variation on the robustness of springback for a semi-cylindrical channel forming operation, which shares a similar cross-section profile as many automotive structural components. The study was conducted using the specialised sheet metal forming package AutoFormTM Sigma, for which a series of stochastic simulations were performed with each of the noise sources incrementally introduced. The effective stress and effective strain scatter in a critical location of the part was examined and a response window, which indicates the respective process robustness, was defined. The incremental introduction of the noise sources allows the change in size of the stressstrain response window to be tracked. The results showed that changes to process variation parameters, such as BHP and friction coefficient, directly affect the strain component of the stressstrain response window by altering the magnitude of external work applied to forming system. Material variation, on the other hand, directly affected the stress component of the response window. A relationship between the effective stressstrain response window and the variation in springback was also established.

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Bangladesh exemplifies the complex challenges facing densely populated coastal regions. The
pressures on the country are immense: around 145 million people live within an area of just 145,000 sq-km at
the confluence of three major river systems: the Ganges, the Brahmaputra and the Meghna. While progress
has been made, poverty remains widespread, with around 39% of children under five malnourished. Most of
its land-mass lies below 10m above sea level with considerable areas at sea level, leading to frequent and
prolonged flooding during the monsoons. Sea level rise is leading to more flooding as storm surges rise off
higher sea levels, pushing further inland. Higher sea levels also result in salt-water intrusion into freshwater
coastal aquifers and estuaries, contaminating drinking water and farmland. Warmer ocean waters are also
expected to lead to an increase in the intensity of tropical storms.
Bangladesh depends on the South Asian summer monsoon for most of its rainfall which is expected to
increase, leading to more flooding. Climate scientists are also concerned about the stability of monsoon and
the potential for it to undergo a nonlinear phase shift to a drier regime. Bangladesh faces an additional
hydrological challenge in that the Ganges and Brahmaputra rivers both rise in the Himalaya-Tibetan Plateau
region, where glaciers are melting rapidly. The Intergovernmental Panel on Climate Change (IPCC)
concluded that rapid melting is expected to increase river flows until around the late-2030s, by which time
the glaciers are expected to have shrunk from their 1995 extent of 500,000 sq-km to an expected 100,000 sqkm.
After the 2030s, river flows could drop dramatically, turning the great glacier-fed rivers of Asia into
seasonal monsoon-fed rivers. The IPCC concluded that as a result, water shortages in Asia could affect more
than a billion people by the 2050s. Over the same period, crop yields are expected to decline by up to 30% in
South Asia due to a combination of drought and crop heat stress. Bangladesh is therefore likely to face
substantial challenges in the coming decades.
In order to adequately understand the complex, dynamic, spatial and nonlinear challenges facing Bangladesh,
an integrated model of the system is required. An agent-based model (ABM) permits the dynamic
interactions of the economic, social, political, geographic, environmental and epidemiological dimensions of
climate change impacts and adaptation policies to be integrated via a modular approach. Integrating these
dimensions, including nonlinear threshold events such as mass migrations, or the outbreak of conflicts or
epidemics, is possible to a far greater degree with an ABM than with most other approaches.
We are developing a prototype ABM, implemented in Netlogo, to examine the dynamic impacts on poverty,
migration, mortality and conflict from climate change in Bangladesh from 2001 to 2100. The model employs
GIS and sub-district level census and economic data and a coarse-graining methodology to allow model
statistics to be generated on a national scale from local dynamic interactions. This approach allows a more
realistic treatment of distributed spatial events and heterogeneity across the country. The aim is not to
generate precise predictions of Bangladesh’s evolution, but to develop a framework that can be used for
integrated scenario exploration. This paper represents an initial report on progress on this project. So far the
prototype model has demonstrated the desirability and feasibility of integrating the different dimensions of
the complex adaptive system and, once completed, is intended to be used as the basis for a more detailed
policy-oriented model.