481 resultados para Specific volume


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Introduction Clinical guidelines for the treatment of chronic low back pain suggest the use of supervised exercise. Motor control (MC) based exercise is widely used within clinical practice but its efficacy is equivalent to general exercise therapy. MC exercise targets the trunk musculature. Considering the mechanical links between the hip, pelvis, and lumbar spine, surprisingly little focus has been on investigating the contribution of the hip musculature to lumbopelvic support. The purpose of this study is to compare the efficacy of two exercise programs for the treatment of non-specific low back pain (NSLBP). Methods Eighty individuals aged 18-65 years of age were randomized into two groups to participate in this trial. The primary outcome measures included self-reported pain intensity (0-100mm VAS) and percent disability (Oswestry Disability Index V2). Bilateral measures of hip strength (N/kg) and two dimensional frontal plane mechanics (º) were the secondary outcomes. Outcomes were measured at baseline and following a six-week home based exercise program including weekly sessions of real-time ultrasound imaging. Results Within group comparisons revealed clinically meaningful reductions in pain for both groups. The MC exercise only (N= 40, xˉ =-20.9mm, 95%CI -25.7, -16.1) and the combined MC and hip exercise (N= 40, xˉ = -24.9mm, 95%CI -30.8, -19.0). There was no statistical difference in the change of pain (xˉ =-4.0mm, t= -1.07, p=0.29, 95%CI -11.5, 3.5) or disability (xˉ =-0.3%, t=-0.19, p=0.85, 95%CI -11.5, 3.5) between groups. Conclusion Both exercise programs had similar and positive effects on NSLBP which support the use of the home based exercise programs with weekly supervised visits. However, the addition of specific hip strengthening exercises to a MC based exercise program did not result in significantly greater reductions in pain or disability. Trial Registration NCTO1567566 Funding: Worker’s Compensation Board Alberta Research Grant.

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Chapters in Book 1 of this two-volume set explored literature pertaining to the shortage of engineers in Australia, the ageing engineering workforce, issues of skilled migration, and career development and pathways. The companion chapter to this one in Book 1 explored attraction and image issues of certain industries that required a pipeline of engineers. This chapter will reflect on our research with final-year engineering students in Australian universities and TAFE colleges regarding their career aspirations, industries and/or organisations that they identify as attractive employers, and their perceptions of a low-profile industry, namely the Australian rail industry. This chapter will also discuss specific, evidence-based strategies and activities to enhance the image and attraction of low-profile industries.

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We show that in melanoma cells oncogenic BRAF, acting through MEK and the transcription factor BRN2, downregulates the cGMP-specific phosphodiesterase PDE5A. Although PDE5A downregulation causes a small decrease in proliferation, its major impact is to stimulate a dramatic increase in melanoma cell invasion. This is because PDE5A downregulation leads to an increase in cGMP, which induces an increase in cytosolic Ca2+, stimulating increased contractility and inducing invasion. PDE5A downregulation also this leads to an increase in short-term and long-term colonization of the lungs by melanoma cells. We do not observe this pathway in NRAS mutant melanoma or BRAF mutant colorectal cells. Thus, we show that in melanoma cells oncogenic BRAF induces invasion through downregulation of PDE5A.

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This paper reports an investigation of the views and practices of 203 Australian psychologists and guidance counsellors with respect to psycho-educational assessment of students with Specific Learning Disabilities (SLDs). Results from an online survey indicated that practitioners draw upon a wide-range of theoretical perspectives when conceptualising and identifying SLDs, including both response to intervention and IQ – achievement discrepancy models. Intelligence tests (particularly the Wechsler scales) are commonly employed, with the main stated reasons for their use being ‘traditional’ perspectives (including IQ-achievement discrepancy-based definitions of SLDs), to exclude a diagnosis of intellectual disability, and to guide further assessment and intervention. In contrast participants reported using measures of academic achievement and tests of specific cognitive deficits known to predict SLDs (e.g., phonological awareness) relatively infrequently.

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Detailed knowledge of the past history of an active volcano is crucial for the prediction of the timing, frequency and style of future eruptions, and for the identification of potentially at-risk areas. Subaerial volcanic stratigraphies are often incomplete, due to a lack of exposure, or burial and erosion from subsequent eruptions. However, many volcanic eruptions produce widely-dispersed explosive products that are frequently deposited as tephra layers in the sea. Cores of marine sediment therefore have the potential to provide more complete volcanic stratigraphies, at least for explosive eruptions. Nevertheless, problems such as bioturbation and dispersal by currents affect the preservation and subsequent detection of marine tephra deposits. Consequently, cryptotephras, in which tephra grains are not sufficiently concentrated to form layers that are visible to the naked eye, may be the only record of many explosive eruptions. Additionally, thin, reworked deposits of volcanic clasts transported by floods and landslides, or during pyroclastic density currents may be incorrectly interpreted as tephra fallout layers, leading to the construction of inaccurate records of volcanism. This work uses samples from the volcanic island of Montserrat as a case study to test different techniques for generating volcanic eruption records from marine sediment cores, with a particular relevance to cores sampled in relatively proximal settings (i.e. tens of kilometres from the volcanic source) where volcaniclastic material may form a pervasive component of the sedimentary sequence. Visible volcaniclastic deposits identified by sedimentological logging were used to test the effectiveness of potential alternative volcaniclastic-deposit detection techniques, including point counting of grain types (component analysis), glass or mineral chemistry, colour spectrophotometry, grain size measurements, XRF core scanning, magnetic susceptibility and X-radiography. This study demonstrates that a set of time-efficient, non-destructive and high-spatial-resolution analyses (e.g. XRF core-scanning and magnetic susceptibility) can be used effectively to detect potential cryptotephra horizons in marine sediment cores. Once these horizons have been sampled, microscope image analysis of volcaniclastic grains can be used successfully to discriminate between tephra fallout deposits and other volcaniclastic deposits, by using specific criteria related to clast morphology and sorting. Standard practice should be employed when analysing marine sediment cores to accurately identify both visible tephra and cryptotephra deposits, and to distinguish fallout deposits from other volcaniclastic deposits.

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The coffee components kahweol and cafestol (K/C) have been reported to protect the colon and other organs of the rat against the formation of DNA adducts by 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP) and aflatoxin B1. PhIP is a cooked-food mutagen to which significant human exposure and a role in colon cancer etiology are attributed, and, interestingly, such cancers appear to develop at a lower rate in consumers of coffees with high amounts of K/C. Earlier studies in rodent liver have shown that a key role in the chemopreventive effect of K/C is likely to be due to the potential of these compounds to induce the detoxification of xenobiotics by glutathione transferase (GST) and to enhance the synthesis of the corresponding co-factor glutathione. However, mutagens like PhIP may also be detoxified by UDP-glucuronosyl transferase (UDPGT) for which data are lacking regarding a potential effect of K/C. Therefore, in the present study, we investigated the effect of K/C on UDPGT and, concomitantly, we studied overall GST and the pattern of individual GST classes, particularly GST-θ, which was not included in earlier experiments. In addition, we analyzed the organ-dependence of these potentially chemopreventive effects. K/C was fed to male F344 rats at 0.122% in the chow for 10 days. Enzyme activities in liver, kidney, lung, colon, salivary gland, pancreas, testis, heart and spleen were quantified using five characteristic substrates and the hepatic protein pattern of GST classes α, μ, and π was studied with affnity chromatography/HPLC. Our study showed that K/C is not only capable of increasing overall GST and GST classes α, μ, and π but also of enhancing UDGPT and GST-θ. All investigated K/C effects were strongest in liver and kidney, and some response was seen in lung and colon but none in the other organs. In summary, our results show that K/C treatment leads to a wide spectrum of increases in phase II detoxification enzymes. Notably, these effects occurred preferentially in the well perfused organs liver and kidney, which may thus not only contribute to local protection but also to anti-carcinogenesis in distant, less stimulated organs such as the colon.

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This Chapter considers a number of sector-specific access regimes that apply to infrastructure that exhibits natural monopoly characteristics. With the exception of Pt XIC of the CCA which regulates access to telecommunications infrastructure, they adopt the same form of negotiate-arbitrate model found in Pt IIIA of the CCA. In the event of a failure to negotiate commercial terms and conditions of access they allow the regulator to impose cost based (building block)tariffs. The regulator's decisions are subject to merits review and/or judicial review. The Chapter is divided into four Parts: • Part I considers access regulation in the electricity sector; • Part II considers access regulation in the gas sector; • Part III considers access regulation in the telecommunications sector; and • Part N considers access regulation in relation to port and rail bulk supply chains.

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After attending this presentation, attendees will gain awareness of the ontogeny of cranial maturation, specifically: (1) the fusion timings of primary ossification centers in the basicranium; and (2) the temporal pattern of closure of the anterior fontanelle, to develop new population-specific age standards for medicolegal death investigation of Australian subadults. This presentation will impact the forensic science community by demonstrating the potential of a contemporary forensic subadult Computed Tomography (CT) database of cranial scans and population data, to recalibrate existing standards for age estimation and quantify growth and development of Australian children. This research welcomes a study design applicable to all countries faced with paucity in skeletal repositories. Accurate assessment of age-at-death of skeletal remains represents a key element in forensic anthropology methodology. In Australian casework, age standards derived from American reference samples are applied in light of scarcity in documented Australian skeletal collections. Currently practitioners rely on antiquated standards, such as the Scheuer and Black1 compilation for age estimation, despite implications of secular trends and population variation. Skeletal maturation standards are population specific and should not be extrapolated from one population to another, while secular changes in skeletal dimensions and accelerated maturation underscore the importance of establishing modern standards to estimate age in modern subadults. Despite CT imaging becoming the gold standard for skeletal analysis in Australia, practitioners caution the application of forensic age standards derived from macroscopic inspection to a CT medium, suggesting a need for revised methodologies. Multi-slice CT scans of subadult crania and cervical vertebrae 1 and 2 were acquired from 350 Australian individuals (males: n=193, females: n=157) aged birth to 12 years. The CT database, projected at 920 individuals upon completion (January 2014), comprises thin-slice DICOM data (resolution: 0.5/0.3mm) of patients scanned since 2010 at major Brisbane Childrens Hospitals. DICOM datasets were subject to manual segmentation, followed by the construction of multi-planar and volume rendering cranial models, for subsequent scoring. The union of primary ossification centers of the occipital bone were scored as open, partially closed or completely closed; while the fontanelles, and vertebrae were scored in accordance with two stages. Transition analysis was applied to elucidate age at transition between union states for each center, and robust age parameters established using Bayesian statistics. In comparison to reported literature, closure of the fontanelles and contiguous sutures in Australian infants occur earlier than reported, with the anterior fontanelle transitioning from open to closed at 16.7±1.1 months. The metopic suture is closed prior to 10 weeks post-partum and completely obliterated by 6 months of age, independent of sex. Utilizing reverse engineering capabilities, an alternate method for infant age estimation based on quantification of fontanelle area and non-linear regression with variance component modeling will be presented. Closure models indicate that the greatest rate of change in anterior fontanelle area occurs prior to 5 months of age. This study complements the work of Scheuer and Black1, providing more specific age intervals for union and temporal maturity of each primary ossification center of the occipital bone. For example, dominant fusion of the sutura intra-occipitalis posterior occurs before 9 months of age, followed by persistence of a hyaline cartilage tongue posterior to the foramen magnum until 2.5 years; with obliteration at 2.9±0.1 years. Recalibrated age parameters for the atlas and axis are presented, with the anterior arch of the atlas appearing at 2.9 months in females and 6.3 months in males; while dentoneural, dentocentral and neurocentral junctions of the axis transitioned from non-union to union at 2.1±0.1 years in females and 3.7±0.1 years in males. These results are an exemplar of significant sexual dimorphism in maturation (p<0.05), with girls exhibiting union earlier than boys, justifying the need for segregated sex standards for age estimation. Studies such as this are imperative for providing updated standards for Australian forensic and pediatric practice and provide an insight into skeletal development of this population. During this presentation, the utility of novel regression models for age estimation of infants will be discussed, with emphasis on three-dimensional modeling capabilities of complex structures such as fontanelles, for the development of new age estimation methods.

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Bacterial tail-specific proteases (Tsps) have been attributed a wide variety of functions including intracellular virulence, cell wall morphology, proteolytic signal cascades and stress response. This study tested the hypothesis that Tsp has a key function for the transmissive form of Legionella pneumophila. A tsp mutant was generated in Legionella pneumophila 130b and the characteristics of this strain and the isogenic wild-type were examined using a range of growth and proteomic analyses. Recombinant Tsp protein was also produced and analyzed. The L. pneumophila tsp mutant showed no defect in growth on rich media or during thermo-osmotic stress conditions. In addition, no defects in cellular morphology were observed when the cells were examined using transmission electron microscopy. Purified recombinant Tsp was found to be an active protease with a narrow substrate range. Proteome analysis using iTRAQ (5% coverage of the proteome) found that, of those proteins detected, only 5 had different levels in the tsp mutant compared to the wild type. ACP (Acyl Carrier Protein), which has a key role for Legionella differentiation to the infectious form, was reduced in the tsp mutant; however, tsp(-) was able to infect and replicate inside macrophages to the same extent as the wild type. Combined, these data demonstrate that Tsp is a protease but is not essential for Legionella growth or cell infection. Thus, Tsp may have functional redundancy in Legionella.

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Purpose In the past, leadership scholars have tended to focus on leadership as a force for good and productivity (Ashworth, 1994; Higgs, 2009; Padilla, Hogan, & Kaiser, 2007). However, recently attention has been given to the ‘dark side’ of leadership (see Higgs, 2009; Judge, Piccolo, & Kosalka, 2009). The aim of this chapter is to explore dark leadership from the perspective of the narcissistic leader using a fictional character from a popular film. Methodology/approach Using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, 1994 (DSM-IV) (American Psychiatric Association, 2000) as an operational definition of narcissistic personality disorder we explore the psychology of the narcissistic leader through a fictional character study in a popular film. Findings We have created a psychological profile of a narcissistic leader which identifies specific behavioural characteristics within a toxic organizational culture. Social implications This study has implications for employees within any organizational culture. It is significant because it can illustrate how dark leadership can impact negatively within organizations. Originality/value The use of actual living persons on which to base case study material in the study of dark leadership is problematic and constrained by ethical issues. However, the use of characters in fiction, such as contemporary film and drama, represents an excellent source of case study material. Given that little empirical works exists on narcissistic leaders and leadership, the chapter adds originality and value to the field.