105 research outputs found

    An evolving ensemble model of multi-stream convolutional neural networks for human action recognition in still images

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    Still image human action recognition (HAR) is a challenging problem owing to limited sources of information and large intra-class and small inter-class variations which requires highly discriminative features. Transfer learning offers the necessary capabilities in producing such features by preserving prior knowledge while learning new representations. However, optimally identifying dynamic numbers of re-trainable layers in the transfer learning process poses a challenge. In this study, we aim to automate the process of optimal configuration identification. Specifically, we propose a novel particle swarm optimisation (PSO) variant, denoted as EnvPSO, for optimal hyper-parameter selection in the transfer learning process with respect to HAR tasks with still images. It incorporates Gaussian fitness surface prediction and exponential search coefficients to overcome stagnation. It optimises the learning rate, batch size, and number of re-trained layers of a pre-trained convolutional neural network (CNN). To overcome bias of single optimised networks, an ensemble model with three optimised CNN streams is introduced. The first and second streams employ raw images and segmentation masks yielded by mask R-CNN as inputs, while the third stream fuses a pair of networks with raw image and saliency maps as inputs, respectively. The final prediction results are obtained by computing the average of class predictions from all three streams. By leveraging differences between learned representations within optimised streams, our ensemble model outperforms counterparts devised by PSO and other state-of-the-art methods for HAR. In addition, evaluated using diverse artificial landscape functions, EnvPSO performs better than other search methods with statistically significant difference in performance

    Effect of comorbid migraine on propranolol efficacy for painful TMD in a randomized controlled trial

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    Introduction The migraine-preventive drug propranolol is efficacious in reducing pain from temporomandibular disorder, suggesting potential modifying or mediating effects of comorbid migraine. Methods In this randomized controlled trial, myofascial temporomandibular disorder patients were treated with propranolol or placebo for 9 weeks. The primary endpoint was change in a facial pain index derived from daily symptom diaries. Linear and logistic regression models tested for a migraine × treatment-group interaction in reducing facial pain index. Counterfactual models explored changes in headache impact and heart rate as mediators of propranolol's efficacy. Results Propranolol's efficacy in reducing facial pain index was greater among the 104 migraineurs than the 95 non-migraineurs: For example, for the binary ≥ 30% reduction in facial pain index, odds ratios were 3.3 (95% confidence limits: 1.4, 8.1) versus 1.3 (0.5, 3.2), respectively, although the interaction was statistically non-significant (p = 0.139). Cumulative response curves confirmed greater efficacy for migraineurs than non-migraineurs (differences in area under the curve 26% and 6%, respectively; p = 0.081). While 9% of the treatment effect was mediated by reduced headache impact, 46% was mediated by reduced heart rate. Conclusions Propranolol was more efficacious in reducing temporomandibular disorder pain among migraineurs than non-migraineurs, with more of the effect mediated by reduced heart rate than by reduced headache impact. Study identification and registration SOPPRANO; NCT02437383; https://clinicaltrials.gov/ct2/show/NCT0243738

    Modification of COMT-dependent pain sensitivity by psychological stress and sex

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    Catecholamine-O-methyltransferase (COMT) is a polymorphic gene whose variants affect enzymatic activity and pain sensitivity via adrenergic pathways. Although COMT represents one of the most studied genes in human pain genetics, findings regarding its association with pain phenotypes are not always replicated. Here, we investigated if interactions among functional COMT haplotypes, stress, and sex can modify the effect of COMT genetic variants on pain sensitivity. We tested these interactions in a cross-sectional study, including 2 cohorts, one of 2972 subjects tested for thermal pain sensitivity (Orofacial Pain: Prospective Evaluation and Risk Assessment) and one of 948 subjects with clinical acute pain after motor vehicle collision (post-motor vehicle collision). In both cohorts, the COMT high-pain sensitivity (HPS) haplotype showed robust interaction with stress and number of copies of the HPS haplotype was positively associated with pain sensitivity in nonstressed individuals, but not in stressed individuals. In the post-motor vehicle collision cohort, there was additional modification by sex: the HPS-stress interaction was apparent in males, but not in females. In summary, our findings indicate that stress and sex should be evaluated in association studies aiming to investigate the effect of COMT genetic variants on pain sensitivity

    Vertical integration and firm boundaries : the evidence

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    Since Ronald H. Coase's (1937) seminal paper, a rich set of theories has been developed that deal with firm boundaries in vertical or input–output structures. In the last twenty-five years, empirical evidence that can shed light on those theories also has been accumulating. We review the findings of empirical studies that have addressed two main interrelated questions: First, what types of transactions are best brought within the firm and, second, what are the consequences of vertical integration decisions for economic outcomes such as prices, quantities, investment, and profits. Throughout, we highlight areas of potential cross-fertilization and promising areas for future work

    Effect of catechol-O-methyltransferase polymorphism on response to propranolol therapy in chronic musculoskeletal pain: a randomized, double-blind, placebo-controlled, crossover pilot study

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    Three common haplotypes in the gene encoding catechol-O-methyltransferase (COMT) have been associated with pain modulation and the risk of developing chronic musculoskeletal pain, namely temporomandibular disorder (TMD). Haplotypes coding for higher enzymatic activity were correlated with lower pain perception. Rodent studies showed that COMT inhibition increases pain sensitivity via β2/3-adrenergic receptors. We hypothesized that the non-selective β-adrenergic antagonist propranolol will reduce clinical and experimental pain in TMD patients in a manner dependent on the subjects’ COMT diplotype

    Multi-ethnic GWAS and meta-analysis of sleep quality identify MPP6 as a novel gene that functions in sleep center neurons

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    Poor sleep quality can have harmful health consequences. Although many aspects of sleep are heritable, the understandings of genetic factors involved in its physiology remain limited. Here, we performed a genome-wide association study (GWAS) using the Pittsburgh Sleep Quality Index (PSQI) in a multi-ethnic discovery cohort (n = 2868) and found two novel genome-wide loci on chromosomes 2 and 7 associated with global sleep quality. A meta-analysis in 12 independent cohorts (100 000 individuals) replicated the association on chromosome 7 between NPY and MPP6. While NPY is an important sleep gene, we tested for an independent functional role of MPP6. Expression data showed an association of this locus with both NPY and MPP6 mRNA levels in brain tissues. Moreover, knockdown of an orthologue of MPP6 in Drosophila melanogaster sleep center neurons resulted in decreased sleep duration. With convergent evidence, we describe a new locus impacting human variability in sleep quality through known NPY and novel MPP6 sleep genes.Peer reviewe

    Applications of sensory and physiological measurement in oral‐facial dental pain

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    Dentists regularly employ a variety of self‐report and sensory techniques to aid in the diagnosis and treatment of tooth‐related disease. Many of these techniques leverage principles borrowed from psychophysics, the quantitative measurement of the relationship between stimuli and evoked sensations, which falls under the larger umbrella of quantitative sensory testing (QST). However, most clinicians fail to meet the bar for what could be considered quantitative sensory testing, and instead focus on qualitative and dichotomous “yes/no” aspects of sensory experience. With our current subjective measurements for pain assessments, diagnosis and treatment of dental pain in young children and individuals (any age) with severe cognitive impairment rely extensively on third‐party observations. Consequently, the limitation of inadequate pain diagnosis can lead to poor pain management. In this review, it discusses mechanisms that underlie acute and chronic dental pain. It details the measurement of somatosensory responses and pulpal blood flow as objective measures of tooth health and pain. It proposes that bridging these varied methodologies will significantly improve diagnosis and treatment of orofacial pain and pathology. It concludes that improving the precision of sensory measurements could yield important improvements in diagnostic challenges in pulpal pathology for noncommunicative and cognitively impaired individuals.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146659/1/scd12323.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146659/2/scd12323_am.pd

    Metagenomics for Bacteriology

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    The study of bacteria, or bacteriology, has gone through transformative waves since its inception in the 1600s. It all started by the visualization of bacteria using light microscopy by Antonie van Leeuwenhoek, when he first described “animalcules.” Direct cellular observation then evolved into utilizing different wavelengths on novel platforms such as electron, fluorescence, and even near-infrared microscopy. Understanding the link between microbes and disease (pathogenicity) began with the ability to isolate and cultivate organisms through aseptic methodologies starting in the 1700s. These techniques became more prevalent in the following centuries with the work of famous scientists such as Louis Pasteur and Robert Koch, and many others since then. The relationship between bacteria and the host’s immune system was first inferred in the 1800s, and to date is continuing to unveil its mysteries. During the last century, researchers initiated the era of molecular genetics. The discovery of the first-generation sequencing technology, the Sanger method, and, later, the polymerase chain reaction technology propelled the molecular genetics field by exponentially expanding the knowledge of relationship between gene structure and function. The rise of commercially available next-generation sequencing methodologies, in the beginning of this century, is drastically allowing larger amount of information to be acquired, in a manner open to the democratization of the approach

    Career self: a longitudinal study with college students

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    O self de carreira constituí um subconjunto organizado do universo cognitivo de uma pessoa, responsável pelo carácter subjetivo que a mesma confere à carreira. Este estudo pretende avaliar mudanças no conteúdo do self de carreira de estudantes universitários, do início para o final do último ano de graduação. Para tal, recorreu-se a medidas repetidas dos índices da Grelha de Repertório da Carreira (Silva & Taveira, 2005; Silva, 2008). Na investigação, participaram 80 estudantes, dos quais 49 são mulheres (61,25%) e 31 são homens (38,75%), com idades entre os 21 e os 45 anos (M= 23,9, DP= 4,31). Os resultados indicam que, no final da licenciatura, os estudantes diminuem a distância como se constrõem em relação aos outros e mantêm uma construção positiva do self de carreira.Fundação para a Ciência e a Tecnologia (FCT
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