342 research outputs found

    Tracking people across disjoint camera views

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    University of Technology, Sydney. Faculty of Information Technology.Tracking people around surveillance systems is becoming increasingly important in the current security conscious environment. This thesis presents a framework to automatically track the movements of individual people in large video camera networks, even where there are gaps between camera views. It is designed to assist security operators, or police investigations by providing additional information about the location of individuals throughout the surveillance area. Footage from an existing surveillance system has been used to test the framework under real conditions. The framework uses the similarity of robust shape and appearance features to match tracks. These features are extracted to build an object feature model as people move within a single camera view, which can be compared across cameras. The integration of matching similarities in the temporal domain increases the robustness to errors of many kinds. Frames with significant segmentation errors can be automatically detected and removed based upon their lack of similarity to the other models within the same track, increasing robustness. The shape and appearance features used to generate the object models are based upon features humans habitually use for identifying individuals. They include a height estimate, a Major Colour Representation (MCR) of the individuals global colours, and estimates of the colours of the upper and lower portions of clothing. The fusion of these features is shown to be complementary, providing increased discrimination between individuals. The MCR colour features are improved through the mitigation of illumination changes using controlled equalisation, which improves the accuracy in matching colour under normal surveillance conditions and requires no training or scene knowledge. The incorporation of other features into this framework is also relatively straightforward. This track matching framework was tested upon four individuals across two video cameras of an existing surveillance system. Existing infrastructure and actors were used to ensure that ground truth is available. Specific cases were constructed to test the limitations of the system when similar clothing is worn. In the data, the height difference ranges from 5 to 30 centimetres, and individuals may only be wearing 50% of similar clothing colours. The accuracy of matching an individual was as high as 91% with only 5% false alarms when all the system components were used. This may not become a fully automated system, but could be used in semi-automated or human assisted systems, or as the basis for further research into improved automated surveillance. Application areas range from forensic surveillance to the matching of the movements of key individuals throughout a surveillance network and possibly even target location

    Kruppel-like factor 4 suppresses neuroblastoma growth by promoting smooth-muscle differentiation

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    Poster Board Number: 2105Neuroblastoma (NB) is an embryonic tumor and possesses a unique propensity to exhibit either a spontaneous regression or an unrestrained growth. Growing evidence suggests that NB comprises heterogeneous populations of improperly differentiated neural crest cells and a small subset of NB cells behaves as stem cells. Commitment of NB stem cells to the fibromuscular lineage may give a favorable outcome, while to the neuronal lineage results in a malignant tumor progression. Kruppel like factor 4 (KLF4) is one of the key reprogramming factors. Intriguingly, it also possesses paradoxical functions in cancers, either as an oncogene or tumor suppressor dependent of cell context. In this study, we elucidated the roles of KLF4 in the lineage determination of NB stem cells and tumor progression. Quantitative RT-PCR showed that loss of KLF4 expression ...published_or_final_versio

    School health partnership in service learning : a Hong Kong experience

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    Seguimiento de las obras hidráulicas de desagüe pluvial de la Región Capital-Evaluación hidrológica e hidráulica

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    En este informe de avance trimestral se describen las tareas de gabinete y campo desarrolladas entre agosto y octubre de 2016, correspondientes a la evaluación hidrológica e hidráulica de las obras de mejora del sistema pluvial en ejecución. Se abordan en forma preliminar los siguientes temas: - Grado de protección que brindan las obras en construcción - Plan de trabajo de las obras en ejecución - Evaluación del tramo Papelera - Empalme del conducto de calle 11 - Estudio de los reservorios de la cuenca alta.Este informe técnico fue presentado en una Reunión técnica de la Comisión Bicameral llevada a cabo en el Salón Directorio de la CIC el 1 de noviembre de 201

    Temporal evolution of soot particles from C2H2/O-2 combustion in a closed chamber

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    An experimental study of soot formation in C2H2/O-2 flames at different C/O ratios in a closed chamber was carried out. The evolution temporal behavior and the volume fraction of soot particles were determined by laser extinction. It was found that total time for the soot formation phenomenon in flames from C2H2/O-2 with C/O ratio >0.75 or C2H2/O-2/Ar with C/O ratio = 1.00 was around 3.0-4.0 ms after ignition. At almost the same time the excited radicals reached their maximum emission intensity and the gases under combustion reached their maximum pressure. The micrographs show compact and approximately spherical soot particles with diameters within 60-150 nm. However, soot aggregates are not compact and they present a netlike structure similar to that of an aerogel.131475

    Synchronized partial-body motion graphs

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    Author name used in this publication: William W. L. NGAuthor name used in this publication: Clifford S. T. ChoyAuthor name used in this publication: Daniel P. K. LunRefereed conference paper2010-2011 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe

    Using illness scripts to teach clinical reasoning skills to medical students

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    Background and Objectives: Most medical students learn clinical reasoning skills informally during clinical rotations that have varying quality of supervision. We conducted a randomized controlled trial to determine if a workshop that uses "illness scripts" could improve students' clinical reasoning skills when making diagnoses of patients portrayed in written scenarios. Methods: In 2007-2008, 53 fourth-year medical students were randomly assigned to either a family medicine (intervention) or psychiatry (control) clerkship at The Chinese University of Hong Kong. Students in the intervention group participated in a 3-hour workshop on clinical reasoning that used illness scripts. The workshop was conducted with small-group teaching using a Web-based set of clinical reasoning problems, individualized feedback, and demonstration of tutors' reasoning aloud. The effectiveness of the intervention was assessed using the Diagnostic Thinking Inventory (DTI) and the measurement of individual students' performance in solving clinical reasoning problems (CRP). Results: The postintervention overall DTI scores between groups were similar (mean difference 0, 95% confidence interval [CI]= -7.4 to 7.4). However, the total scores on the CRP assessment were 14% (95% CI=8% to 21%) higher in the intervention group than in controls. Conclusion: A workshop on illness scripts may have some benefit for improving diagnostic performance in clinical reasoning problems.link_to_OA_fulltex

    Greater variability in lipid measurements associated with kidney diseases in patients with type 2 diabetes mellitus in a 10-year diabetes cohort study.

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    This study aimed to evaluate the associations between variability of lipid parameters and the risk of kidney disease in patients with type 2 diabetes mellitus. Low-density lipoprotein-cholesterol, total cholesterol to high-density lipoprotein-cholesterol ratio and triglyceride were specifically addressed in this study. This retrospective cohort study included 105,552 patients aged 45-84 with type 2 diabetes mellitus and normal kidney function who were managed under Hong Kong public primary care clinics during 2008-2012. Those with kidney disease (estimated glomerular filtration rate < 60 mL/min/1.73 m2 or urine albumin to creatinine ratio ≥ 3 mg/mmol) were excluded. Variabilities of low-density lipoprotein-cholesterol, total cholesterol to high-density lipoprotein-cholesterol ratio and triglyceride were determined using the standard deviation of the respective parameter obtained from a mixed effects model to minimize regression dilution bias. The associations between lipid variability and renal outcomes including incident kidney disease, renal function decline defined as ≥ 30% reduction in estimated glomerular filtration rate since baseline, and end-stage renal disease (estimated glomerular filtration rate < 15 mL/min/1.73 m2) were evaluated by multivariable Cox regression. After a median follow-up of 66.5 months (0.5 million person-years in total), 49,653 kidney disease, 29,358 renal function decline, and 1765 end-stage renal disease cases were recorded. Positive linear associations between low-density lipoprotein-cholesterol and total cholesterol to high-density lipoprotein-cholesterol ratio variabilities and the risk of all renal outcomes were demonstrated. However, no association between triglyceride variability and any outcome was found. Each mmol/L increase in low-density lipoprotein-cholesterol variability was associated with 20% (Hazard ratio 1.20 [95% CI 1.15-1.25]), 38% (Hazard ratio 1.37 [95% CI 1.30-1.45]), and 108% (Hazard ratio 2.08 [95% CI 1.74-2.50]) higher risk in incident kidney disease, renal function decline and end-stage renal disease respectively. Similarly, each unit increase in total cholesterol to high-density lipoprotein-cholesterol ratio variability was associated with 35% (Hazard ratio 1.15 [95% CI 1.10-1.20]), 33% (Hazard ratio 1.33 [95% CI 1.26-1.40]), and 75% (Hazard ratio 1.75 [95% CI 1.46-2.09]) heightened risk in incident kidney disease, renal function decline and end-stage renal disease respectively. Cholesterol variability may potentially be a useful predictor of kidney diseases in patients with type 2 diabetes mellitus. Attention should be drawn to cholesterol variability when managing diabetic patients and further research is warranted to investigate the modifiable risk factors for lipid variability

    Implementing the WHO caregivers skills training program with caregivers of autistic children via telehealth in rural communities

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    Background: For families with autistic children living in rural areas, limited access to services partly results from a shortage of providers and extensive travel time. Telehealth brings the possibility of implementing alternative delivery modalities of Parent Mediated Interventions (PMIs) with the potential to decrease barriers to accessing services. This study aimed to evaluate the feasibility and acceptability of implementing the World Health Organization-Caregivers Skills Training program (WHO-CST) via an online, synchronous group format in rural Missouri. Methods: We used a mixed methods design to collect qualitative and quantitative data from caregivers and program facilitators at baseline and the end of the program, following the last home visit. Caregivers of 14 autistic children (3-7 years), residents of rural Missouri, completed nine virtual sessions and four virtual home visits. Results: Four main themes emerged from the focus groups: changes resulting from the WHO-CST, beneficial aspects of the program, advantages and disadvantages of the online format, and challenges to implementing the WHO-CST via telehealth. The most liked activity was the demonstration (36%), and the least liked was the practice with other caregivers. From baseline to week 12, communication skills improved in both frequency (p \u3c 0.05) and impact (p \u3c 0.01), while atypical behaviors decreased (p \u3c 0.01). For caregivers\u27 outcomes, only confidence in skills (p \u3c 0.05) and parental sense of competence (p \u3c 0.05) showed a positive change. Conclusion: Our results support the feasibility of implementing the WHO-CST program via telehealth in a US rural setting. Caregivers found strategies easy to follow, incorporated the program into their family routines, and valued the group meetings that allowed them to connect with other families. A PMI such as the WHO-CST, with cultural and linguistic adaptations and greater accessibility via telehealth-plays an essential role in closing the treatment gap and empowering caregivers of autistic children

    Correction of Hirschsprung-Associated Mutations in Human Induced Pluripotent Stem Cells Via Clustered Regularly Interspaced Short Palindromic Repeats/Cas9, Restores Neural Crest Cell Function

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    ACKGROUND & AIMS: Hirschsprung disease is caused by failure of enteric neural crest cells (ENCCs) to fully colonize the bowel, leading to bowel obstruction and megacolon. Heterozygous mutations in the coding region of the RET gene cause a severe form of Hirschsprung disease (total colonic aganglionosis). However, 80% of HSCR patients have short-segment Hirschsprung disease (S-HSCR), which has not been associated with genetic factors. We sought to identify mutations associated with S-HSCR, and used the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 gene editing system to determine how mutations affect ENCC function. METHODS: We created induced pluripotent stem cell (iPSC) lines from 1 patient with total colonic aganglionosis (with the G731del mutation in RET) and from 2 patients with S-HSCR (without a RET mutation), as well as RET+/- and RET-/- iPSCs. IMR90-iPSC cells were used as the control cell line. Migration and differentiation capacities of iPSC-derived ENCCs were analyzed in differentiation and migration assays. We searched for mutation(s) associated with S-HSCR by combining genetic and transcriptome data from patient blood- and iPSC-derived ENCCs, respectively. Mutations in the iPSCs were corrected using the CRISPR/Cas9 system. RESULTS: ENCCs derived from all iPSC lines, but not control iPSCs, had defects in migration and neuronal lineage differentiation. RET mutations were associated with differentiation and migration defects of ENCCs in vitro. Genetic and transcriptome analyses associated a mutation in the vinculin gene (VCL M209L) with S-HSCR. CRISPR/Cas9 correction of the RET G731del and VCL M209L mutations in iPSCs restored the differentiation and migration capacities of ENCCs. CONCLUSIONS: We identified mutations in VCL associated with S-HSCR. Correction of this mutation in iPSC using CRISPR/Cas9 editing, as well as the RET G731del mutation that causes Hirschsprung disease with total colonic aganglionosis, restored ENCC function. Our study demonstrates how human iPSCs can be used to identify disease-associated mutations and determine how they affect cell functions and contribute to pathogenesis.postprin
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