441 research outputs found
Investigation of shock waves in explosive blasts using fibre optic pressure sensors
The published version of this article may be accessed at the link below. Copyright @ IOP Publishing, 2006.We describe miniature all-optical pressure sensors, fabricated by wafer etching techniques, less than 1 mm(2) in overall cross-section with rise times in the mu s regime and pressure ranges typically 900 kPa (9 bar). Their performance is suitable for experimental studies of the pressure-time history for test models exposed to shocks initiated by an explosive charge. The small size and fast response of the sensors promises higher quality data than has been previously available from conventional electrical sensors, with potential improvements to numerical models of blast effects. Results from blast tests are presented in which up to six sensors were multiplexed, embedded within test models in a range of orientations relative to the shock front.Support from the UK Engineering&Physical
Sciences Research Council and Dstl Fort Halstead through the MoD Joint Grants Scheme are acknowledged. WN MacPherson is supported by an EPSRC Advanced Research Fellowship
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Motor phenotypes, medication and mood: further associations with impulsive behaviours in Parkinson's disease
BACKGROUND: Dopaminergic drugs are the primary risk factor for Impulse Control Behaviours (ICB) in Parkinson's disease (PD), others being early-onset disease and gender.
OBJECTIVE: This report further explores ICB symptom relationships with motor and mood phenotypes, the complex relationship with dopaminergic medications, and hypothesizes a model with potential clinical implications.
METHODS: Data from 500 PD patients were analyzed. Hypersexuality, gambling and shopping behaviour were assessed using selected questions from the Minnesota Impulsive Disorders Interview questionnaire. Local questions assessed hobbyism. Motor characteristics considered were akinetic-rigid/gait disturbance (PIGD) and 'non-PIGD' phenotypes, motor severity, motor progression, and presence/absence of motor fluctuations. Other variables included anxiety, depression, current levodopa and agonist use, age, gender and cognition.
RESULTS: Overall, ICB symptom frequency was 17.8%. There was no relationship between PIGD/non-PIGD motor phenotypes and ICB symptoms. Those with ICB symptoms had higher total combined levodopa/agonist equivalent intake, but not current agonist-only equivalent intake. ICB symptoms were reported by 23.1% of those taking combined levodopa and agonist compared to 19.2% on agonist monotherapy and 11.6% levodopa monotherapy. Compared with non-ICB patients, patients with ICB symptoms were more likely to show an anxious mood phenotype, reported more motor fluctuations, and were younger.
CONCLUSIONS: Both PIGD and non-PIGD phenotypes are equally affected. Dose-related risk applies to total anti-parkinsonian medication and not just current agonist-only. Anxious mood phenotypes may carry increased risk. A role of anxiety, either as a marker of risk, indirect causal factor, or maintaining factor is incorporated into a preliminary model. We discuss implications for clinical management
Anxiety and anxious-depression in Parkinson's disease over a 4-year period: A latent transition analysis
Background: Depression and anxiety in Parkinson's disease are common and frequently co-morbid, with significant impact on health outcome. Nevertheless, management is complex and often suboptimal. The existence of clinical subtypes would support stratified approaches in both research and treatment.
Method: Five hundred and thirteen patients with Parkinson's disease were assessed annually for up to 4 years. Latent transition analysis (LTA) was used to identify classes that may conform to clinically meaningful subgroups, transitions between those classes over time, and baseline clinical and demographic features that predict common trajectories.
Results: In total, 64.1% of the sample remained in the study at year 4. LTA identified four classes, a 'Psychologically healthy' class (approximately 50%), and three classes associated with psychological distress: one with moderate anxiety alone (approximately 20%), and two with moderate levels of depression plus moderate or severe anxiety. Class membership tended to be stable across years, with only about 15% of individuals transitioning between the healthy class and one of the distress classes. Stable distress was predicted by higher baseline depression and psychiatric history and younger age of onset of Parkinson's disease. Those with younger age of onset were also more likely to become distressed over the course of the study.
Conclusions: Psychopathology was characterized by relatively stable anxiety or anxious-depression over the 4-year period. Anxiety, with or without depression, appears to be the prominent psychopathological phenotype in Parkinson's disease suggesting a pressing need to understanding its mechanisms and improve management
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When is a Publishing Business Truly ‘Global’? An Analysis of a Routledge Case Study with Reference to Ohmae’s Theory of Globalization
This study first reviews the writing of the management theorist Kenichi Ohmae, before assessing the potential application of his theory of global commercial maturation to the strategies adopted by the academic publishing company, Routledge, and its precursor imprints between 1960 and 2013. Based on the analysis of interviews carried out between 2011 and 2013 and supporting document analysis, the paper concludes that, with some caveats, the stages of globalization identified by Ohmae are of considerable explanatory value for students and analysts of global publishing as well as offering strategic insights to managers of academic publishing houses
Impact of childhood experiences on the development of entrepreneurial intentions
Fostering entrepreneurship and an entrepreneurial culture has become a key policy priority for governments. To encourage entrepreneurship and an entrepreneurial culture, however, there is a need to understand the factors that influence and shape individuals' intentions to start a business. This study extends models of entrepreneurial intentions by investigating the influence of various childhood-experience factors on the perceived feasibility and desirability of starting a business. A structured questionnaire was completed by over 1,000 university students and analysed using regression analysis. Results indicated that perceptions of entrepreneurship were influenced not only by parental ownership of a business, but also by a difficult childhood and frequent relocation
Cross-sectional associations between personality traits and device-based measures of step count and sedentary behaviour in older age: the Lothian Birth Cohort 1936
Background: While the associations between personality traits and self-reported physical activity are well replicated, few studies have examined the associations between personality and device-based measures of both physical activity and sedentary behaviour. Low levels of physical activity and high levels of sedentary behaviour are known risk factors for poorer health outcomes in older age. Methods: We used device-based measures of physical activity and sedentary behaviour recorded over 7 days in 271 79-year-old participants of the Lothian Birth Cohort 1936. Linear regression models were used to assess whether personality traits were cross-sectionally associated with step count, sedentary time, and the number of sit-to-stand transitions. Personality traits were entered one at a time, and all-together, controlling for age and sex in Model 1 and additionally for BMI and limiting long-term illness in Model 2. Results: None of the associations between personality traits and measures of physical activity and sedentary behaviours remained significant after controlling for multiple-comparisons using the False Discovery Rate test (all ps >.07). Conclusions: We found no evidence that personality traits are associated with device-based measures of physical activity or sedentary behaviour in older age. More studies are needed to replicate and examine the nature of these relationships.</p
An environment for relation mining over richly annotated corpora: the case of GENIA
BACKGROUND: The biomedical domain is witnessing a rapid growth of the amount of published scientific results, which makes it increasingly difficult to filter the core information. There is a real need for support tools that 'digest' the published results and extract the most important information. RESULTS: We describe and evaluate an environment supporting the extraction of domain-specific relations, such as protein-protein interactions, from a richly-annotated corpus. We use full, deep-linguistic parsing and manually created, versatile patterns, expressing a large set of syntactic alternations, plus semantic ontology information. CONCLUSION: The experiments show that our approach described is capable of delivering high-precision results, while maintaining sufficient levels of recall. The high level of abstraction of the rules used by the system, which are considerably more powerful and versatile than finite-state approaches, allows speedy interactive development and validation
The topical study of inhaled drug (salbutamol) delivery in idiopathic pulmonary fibrosis
Elastic and inelastic light scattering from single bacterial spores in an optical trap allows the monitoring of spore germination dynamics
Raman scattering spectroscopy and elastic light scattering intensity (ESLI) were used to simultaneously measure levels of Ca-dipicolinic acid (CaDPA) and changes in spore morphology and refractive index during germination of individual B. subtilis spores with and without the two redundant enzymes (CLEs), CwlJ and SleB, that degrade sporesâ peptidoglycan cortex. Conclusions from these measurements include: 1) CaDPA release from individual wild-type germinating spores was biphasic; in a first heterogeneous slow phase, Tlag, CaDPA levels decreased â ¼15% and in the second phase ending at Trelease, remaining CaDPA was released rapidly; 2) in L-alanine germination of wild-type spores and spores lacking SleB: a) the ESLI rose â ¼2-fold shortly before Tlag at T1; b) following Tlag, the ESLI again rose â ¼2-fold at T2 when CaDPA levels had decreased â ¼50%; and c) the ESLI reached its maximum value at â ¼Trelease and then decreased; 3) in CaDPA germination of wild-type spores: a) Tlag increased and the first increase in ESLI occurred well before Tlag, consistent with different pathways for CaDPA and L-alanine germination; b) at Trelease the ESLI again reached its maximum value; 4) in L-alanine germination of spores lacking both CLEs and unable to degrade their cortex, the time Î Trelease (Treleaseâ Tlag) for excretion of â ¥75% of CaDPA was â ¼15-fold higher than that for wild-type or sleB spores; and 5) spores lacking only CwlJ exhibited a similar, but not identical ESLI pattern during L-alanine germination to that seen with cwlJ sleB spores, and the high value for Î Trelease. Originally published Analytical Chemistry, Vol. 81, No. 10, May 200
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