62 resultados para orientamento :: 348 :: Affidabilità e qualita
Resumo:
Abnormal event detection has attracted a lot of attention in the computer vision research community during recent years due to the increased focus on automated surveillance systems to improve security in public places. Due to the scarcity of training data and the definition of an abnormality being dependent on context, abnormal event detection is generally formulated as a data-driven approach where activities are modeled in an unsupervised fashion during the training phase. In this work, we use a Gaussian mixture model (GMM) to cluster the activities during the training phase, and propose a Gaussian mixture model based Markov random field (GMM-MRF) to estimate the likelihood scores of new videos in the testing phase. Further-more, we propose two new features: optical acceleration, and the histogram of optical flow gradients; to detect the presence of any abnormal objects and speed violations in the scene. We show that our proposed method outperforms other state of the art abnormal event detection algorithms on publicly available UCSD dataset.
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Irregular atrial pressure, defective folate and cholesterol metabolism contribute to the pathogenesis of hypertension. However, little is known about the combined roles of the methylenetetrahydrofolate reductase (MTHFR), apolipoprotein-E (ApoE) and angiotensin-converting enzyme (ACE) genes, which are involved in metabolism and homeostasis. The objective of this study is to investigate the association of the MTHFR 677 C>T and 1298A>C, ACE insertion–deletion (I/D) and ApoE genetic polymorphisms with hypertension and to further explore the epistasis interactions that are involved in these mechanisms. A total of 594 subjects, including 348 normotensive and 246 hypertensive ischemic stroke subjects were recruited. The MTHFR 677 C>T and 1298A>C, ACE I/D and ApoEpolymorphisms were genotyped and the epistasis interaction were analyzed. The MTHFR 677 C>T and ApoE polymorphisms demonstrated significant associations with susceptibility to hypertension in multiple logistic regression models, multifactor dimensionality reduction and a classification and regression tree. In addition, the logistic regression model demonstrated that significant interactions between the ApoE E3E3, E2E4, E2E2 and MTHFR 677 C>T polymorphisms existed. In conclusion, the results of this epistasis study indicated significant association between the ApoE and MTHFR polymorphisms and hypertension.
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Addiction is a devastating disorder that affects 15.3 million people worldwide. While prevalent, few effective treatments exist. Orexin receptors have been proposed as a potential target for anti-craving medications. Orexins, also known as hypocretins, are neuropeptides produced in neurons of the lateral and dorsomedial hypothalamus and perifornical area, which project widely throughout the brain. The absence of orexins in rodents and humans leads to narcolepsy. However, orexins also have an established role in reward seeking. This review will discuss some of the original studies describing the roles of the orexins in reward seeking as well as specific works that were presented at the 2013 International Narcotics Research Conference. Orexin signalling can promote drug-induced plasticity of glutamatergic synapses onto dopamine neurons of the ventral tegmental area (VTA), a brain region implicated in motivated behaviour. Additional evidence suggests that orexin signalling can also promote drug seeking by initiating an endocannabinoid-mediated synaptic depression of GABAergic inputs to the VTA, and thereby disinhibiting dopaminergic neurons. Orexin neurons co-express the inhibitory opioid peptide dynorphin. It has been proposed that orexin in the VTA may not mediate reward per se, but rather occludes the ‘anti-reward’ effects of dynorphin. Finally, orexin signalling in the prefrontal cortex and the central amygdala is implicated in reinstatement of reward seeking. This review will highlight recent work describing the role of orexin signalling in cellular processes underlying addiction-related behaviours and propose novel hypotheses for the mechanisms by which orexin signalling may impart drug seeking.
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DNA may take a leading role in a future generation of blockbuster therapeutics. DNA has inherent advantages over other biomolecules such as protein, RNA and virus-like particles including safety, production simplicity and higher stability at ambient temperatures. Vaccination is the principal measure for preventing influenza and reducing the impact of pandemics; however, vaccines take up to 8-9 months to produce, and the global production capacity is woefully low. With production times as short as 2 weeks, improved safety and stability, bioprocess engineering developments, and the ability to perform numerous therapeutic roles, DNA has the potential to meet the demands of emerging and existing diseases. DNA is experiencing sharp growths in demand as indicated by its use in gene therapy trials and DNA vaccine related patents. Of particular interest for therapeutic use is plasmid DNA (pDNA), a form of non-genomic DNA that makes use of cellular machinery to express proteins or antigens. The production stages of fermentation and downstream purification are considered in this article. Forward looking approaches to purifying and delivering DNA are reported, including affinity chromatography and nasal inhalation. The place that pDNA may take in the preparation for and protection against pandemics is considered. If DNA therapeutics and vaccines prove to be effective, the ultimate scale of production will be huge which shall require associated bioprocess engineering research and development for purification of this large, unique biomolecule.
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This paper is drawn from a 2012-2013 OLT National Teaching Fellowship investigating the agencies impacting on whole-of course curriculum design in initial teacher education. The chief of these is AITSL (Australian Institute for Teaching and School Leadership) through the Australian Professional Standards for Teachers at Graduate level and the Program Accreditation Standards. This paper will begin with a discussion of the requirements on both beginning teachers and initial teacher education programs in regard to ICT (both content and pedagogy). It will then present case studies from four universities whose degree programs have been approved for implementation in 2014. It will focus on how each institution has responded to the APST as well as accreditation requirements. This will be based on responses to surveys to selected institutions and with one on one interviews to capture rich data. From this, it will draw a contemporary profile of how institutions are rising to the real requirements of ICT pedagogy within the regulatory constraints now in place. The methodology employed is qualitative and is based on document analysis enriched by interview data. It is important to know, as a profession, how future teachers are being introduced to and immersed in digital learning environments.
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Background There is a need for better understanding of the dispersion of classification-related variable to develop an evidence-based classification of athletes with a disability participating in stationary throwing events. Objectives The purposes of this study are (A) to describe tools designed to comprehend and represent the dispersion of the performance between successive classes, and (B) to present this dispersion for the elite male and female stationary shot-putters who participated in Beijing 2008 Paralympic Games. Study design Retrospective study Methods This study analysed a total of 479 attempts performed by 114 male and female stationary shot-putters in three F30s (F32-F34) and six F50s (F52-F58) classes during the course of eight events during Beijing 2008 Paralympic Games. Results The average differences of best performance were 1.46±0.46 m for males between F54 and F58 classes as well as 1.06±1.18 m for females between F55 and F58 classes. The results demonstrated a linear relationship between best performance and classification while revealing two male Gold Medallists in F33 and F52 classes were outliers. Conclusions This study confirms the benefits of the comparative matrices, performance continuum and dispersion plots to comprehend classification-related variables. The work presented here represents a stepping stone into biomechanical analyses of stationary throwers, particularly on the eve of the London 2012 Paralympic Games where new evidences could be gathered.
Resumo:
Modern commercial agricultural practices in Asia during the last three to four decades involving chemicals (fertilisers and pesticides) have been associated with large increases in food production never witnessed before, especially under the Green Revolution technology in South Asia. This also involves large-scale increases in commercial vegetable crops. However, the high reliance on chemical inputs to bring about these increases in food production is not without problems. A visible, parallel correlation between higher productivity, high artificial input use and environmental degradation and human ill-health is evident in many countries where commercial agriculture is widespread. In this chapter, we focus on the impact of chemical inputs, in particular the impact of pesticides on the environment and on human health in South Asia with special reference to Sri Lanka...
Resumo:
Purpose Little is known about the adoption of mobile banking technologies in emerging Asian economies. This paper aims to empirically examine the motivators that influence a consumer’s intentions to use mobile banking. Design/methodology/approach A web-based survey was employed to collect data from 348 respondents, split across Thailand and Australia. Data were analyzed by employing exploratory and confirmatory factor analyses, path and invariance analyses. Findings The findings indicate that for Australian consumers, perceived ease of use, perceived usefulness and perceived risk were the primary determinants of mobile banking adoption. For Thai consumers, the main factors were perceived usefulness, perceived risk and social influence. National culture was found to impact key antecedents that lead to adoption of m-banking. Research limitations/implications The actual variance explained by our study’s model was higher in Australia (59.3%) than for Thailand (23.8%), suggesting future research of m-banking adoption in emerging Asian cultures. Practical implications We identify the important factors consumers consider when adopting m-banking. The findings of this research give banking organisations a foundational model that can be used to support m-banking implementation. Originality/value Our study is perhaps the first to examine and compare the intention to adopt m-banking across Thai and Australian consumers, and responds to calls for additional research that generalises m-banking and m-services acceptance across cultures. This study has proposed and validated additional constructs that are not present in the original SST Intention to Use model.
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Background In the emergency department, portable point-of-care testing (POCT) coagulation devices may facilitate stroke patient care by providing rapid International Normalized Ratio (INR) measurement. The objective of this study was to evaluate the reliability, validity, and impact on clinical decision-making of a POCT device for INR testing in the setting of acute ischemic stroke (AIS). Methods A total of 150 patients (50 healthy volunteers, 51 anticoagulated patients, 49 AIS patients) were assessed in a tertiary care facility. The INR's were measured using the Roche Coaguchek S and the standard laboratory technique. Results The interclass correlation coefficient and 95% confidence interval between overall POCT device and standard laboratory value INRs was high (0.932 (0.69 - 0.78). In the AIS group alone, the correlation coefficient and 95% CI was also high 0.937 (0.59 - 0.74) and diagnostic accuracy of the POCT device was 94%. Conclusions When used by a trained health professional in the emergency department to assess INR in acute ischemic stroke patients, the CoaguChek S is reliable and provides rapid results. However, as concordance with laboratory INR values decreases with higher INR values, it is recommended that with CoaguChek S INRs in the > 1.5 range, a standard laboratory measurement be used to confirm the results.
Resumo:
This study empirically examines the motivators that influence a consumer’s intentions to use mobile banking. A web-based survey was employed to collect data from 348 respondents, split across Thailand and Australia. Data were analysed by employing exploratory and confirmatory factor analyses, path and invariance analyses. The findings indicate that for Australian consumers, perceived ease of use, perceived usefulness and perceived risk were the primary determinants of mobile banking adoption. For Thai consumers, the main factors were perceived usefulness, perceived risk and social influence. National culture was found to impact key antecedents that lead to adoption of m-banking. Interestingly, the actual variance explained by this study’s model was higher in Australia than for Thailand, suggesting future research of m-banking adoption in emerging Asian cultures. The findings of this research give banking organisations a foundational model that can be used to support m-banking implementation. This study is perhaps the first to examine and compare the intention to adopt m-banking across Thai and Australian consumers, and responds to calls for additional research that generalises m-banking and m-services acceptance across cultures. This study has proposed and validated additional constructs that are not present in the original SST Intention to Use model.
Resumo:
There is increasing momentum within the construction industry to deploy distributed teams on projects, yet the major challenges that companies face for managing teams in distributed arrangements have yet to be explored in the construction context. Driven by such need, this study is intended to present an account of the major challenges encountered throughout the life cycle of offshore outsourcing arrangements within the South Australian construction industry. To this end, the study describes the observations made within the natural contexts of one construction project in terms of the challenges to the success of deploying distributed teams for outsourcing of works. Discussions remain in dialogue with relevant theories and the pertinent literature to explain the interpretations and lessons learned and to underpin the conclusions made. It is contended that this study contributes to the field by providing an illuminating insight into potential challenges facing distributed teams being implemented in outsourcing tasks in construction projects. Discussions also offer practical guidelines for construction project managers and assist them in dealing with potential challenges of offshore outsourcing through the lenses of distributed team working principles.
Resumo:
Flexible multilayer electrodes that combine high transparency, high conductivity, and efficient charge extraction have been deposited, characterised and used as the anode in organic solar cells. The anode consists of an AZO/Ag/AZO stack plus a very thin oxide interlayer whose ionization potential is fine-tuned by manipulating its gap state density to optimise charge transfer with the bulk heterojunction active layer consisting of poly(n-3- hexylthiophene-2,5-diyl) and phenyl-C61-butyric acid methyl ester (P3HT:BC61BM). The deposition method for the stack was compatible with the low temperatures required for polymer substrates. Optimisation of the electrode stack was achieved by modelling the optical and electrical properties of the device and a power conversion efficiency of 2.9% under AM1.5 illumination compared to 3.0% with an ITO-only anode and 3.5% for an ITO:PEDOT electrode. Dark I-V reverse bias characteristics indicate very low densities of occupied buffer states close to the HOMO level of the hole conductor, despite observed ionization potential being high enough. Their elimination should raise efficiency to that with ITO:PEDOT.
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This study investigated whether bystanders of traditional bullying and cyberbullying used face-to-face methods, online methods or both methods when reporting, discouraging and providing support to the victims of traditional bullying and cyberbullying. A questionnaire was completed by 348 high school students (Years 7 – 12) from seven independent schools in Australia. Overall, students predominantly utilized face-to-face methods when reporting to others for both types of bullying. Older students were more likely to use online methods to discourage the traditional bully (i.e., asking the bully to stop). Males and older students were more likely to use online methods to support victims of traditional bullying. Females were more likely to use face-to-face methods to support victims of cyberbullying. Implications for practice and future research are discussed.