363 research outputs found
Inattentional Blindness for Redirected Walking Using Dynamic Foveated Rendering
Redirected walking is a Virtual Reality(VR) locomotion technique which
enables users to navigate virtual environments (VEs) that are spatially larger
than the available physical tracked space. In this work we present a novel
technique for redirected walking in VR based on the psychological phenomenon of
inattentional blindness. Based on the user's visual fixation points we divide
the user's view into zones. Spatially-varying rotations are applied according
to the zone's importance and are rendered using foveated rendering. Our
technique is real-time and applicable to small and large physical spaces.
Furthermore, the proposed technique does not require the use of stimulated
saccades but rather takes advantage of naturally occurring saccades and blinks
for a complete refresh of the framebuffer. We performed extensive testing and
present the analysis of the results of three user studies conducted for the
evaluation
Abdominal tuberculosis: Diagnosis and demographics, a 10-year retrospective review from a single centre.
AIM: To review all cases of abdominal tuberculosis (ATB) for demographic details, diagnostic work up and evidence of vitamin D deficiency. METHODS: This was a retrospective analysis of all patients diagnosed with ATB from June 2003 to August 2013 at St George's Hospital, London. Demographic data was available from the local tuberculosis database. Further clinical information was collected from electronic patient records, including radiology, endoscopy, microbiology, histology, biochemistry and serology. Patients were classified as either confirmed ATB [if mycobacteria tuberculosis (MTB) was cultured from abdominal site] or presumed ATB (if suggestive findings or high clinical suspicion). Subtypes of ATB were classified as tuberculosis (TB) peritonitis, luminal TB, solid organ TB or from a combination of sites. RESULTS: There were a total of 65 cases identified in this time period, with a mean of 6.5 cases per year (range 4-9). Mean age 42 years, 49.2% females. Fifty-two point three percent were South Asian, 38.5% African. Forty-nine point two percent had gastrointestinal endoscopy, 30.8% paracentesis and 24.6% surgery in order to obtain samples. Forty-seven point seven percent were defined as confirmed ATB with positive culture of MTB from abdominal sites, the rest were treated as presumed ATB. Twenty-four point six percent had co-existing sputum culture positive for MTB, and 30.8% had an abnormal chest X-ray. Subtypes of ATB: 35.4% had TB peritonitis; 27.7% luminal TB; 3.1% solid organ TB; and 33.8% TB at a combination of abdominal sites. Thirteen point nine percent were human immunodeficiency virus positive, all with CD4 count less than 300 cells/μL. Seventy point five percent had severe vitamin D deficiency, and 25% were vitamin D deficient. CONCLUSION: ATB mainly affects young South Asian and African patients, with difficulties in confirming diagnosis despite a range of non-invasive and invasive diagnostic tests
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Gastrointestinal symptoms in acromegaly: A case control study
BACKGROUND
Acromegaly is a chronic disease caused by a pituitary somatotroph adenoma resulting in excess secretion of growth hormone, which leads to excess secretion of Insulin like growth factor 1 from the liver, causing abnormal soft tissue growth. There is increasing awareness that diseases affecting connective tissue are associated with an increase in functional gastrointestinal symptoms. Data was collected from patients with a confirmed diagnosis of acromegaly to evaluate the intensity, variety and impact of abdominal symptoms in comparison with a control group who were healthy participants recruited from the local fracture clinic.
AIM
To evaluate the frequency type and burden of abdominal symptoms in acromegaly in comparison with a control group.
METHODS
Medical documentation of patients with a diagnosis of acromegaly treated in one tertiary medical centre between 2010 and 2017 has been analysed. Data was collected from patients with confirmed acromegaly, using the Short Form Health Survey (SF36) and Rome IV Diagnostic questionnaire for Functional Gastrointestinal Disorders in Adults (R4DQ) and compared to a sex- and age-matched control group, to assess the burden of abdominal symptoms. Microsoft Excel and IBM SPSS v 25 were used for data analysis.
RESULTS
Fifty patients with acromegaly (24 male and 26 females; age range 23-64 years, mean 43) and 200 controls (96 male and 104 females; age range 18-84, mean 42.4) were recruited. 92% (46 out of 50) of patients with acromegaly reported abdominal symptoms and 78% (39 out of 50) had at least one functional gastrointestinal disorder according to the Rome IV diagnostic criteria, compared to 16% of controls (OR > 1, P 1, P 1, P < 0.001) as compared to the control group.
CONCLUSION
Upper and lower functional gastrointestinal tract disorders (defined by Rome IV diagnostic criteria) are significantly more prevalent in patients with acromegaly compared with healthy age and sex matched controls in our study. Functional constipation is the most commonly reported problem. Poorer quality of life may in part be attributable to the increased prevalence of abdominal symptoms
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The therapeutic relationship and its links to emotional intelligence
The importance of emotional intelligence (EI) as a theoretical construct to understand human emotions has become quite prominent over the last two decades. However, the concept of EI has not been frequently applied to the therapeutic setting. This study investigated the role that EI plays in therapy, the therapist’s perspective of trait EI in his or her work, and the meaning of the therapeutic relationship from therapists’ perspectives. From interviewing 12 counselling psychologists and therapists, and analysing their responses using a grounded theory approach. The main themes that emerged from the data collected were empathetic balance, benevolent connection and mindfulness. Within these themes a number of findings were established. Most EI traits appear to be present within the therapy setting, albeit not in an overtly conscious way. There was also a sense that EI cannot adequately explain or describe the subtle yet very real emotional connection and empathy that the therapist and the client share and experience. From these findings, I present various recommendations for future research to explore the relevance of EI in the therapeutic setting. One suggestion is to explore the differences between ability and trait EI within the therapeutic relationship while another recommends development of appropriate EI teaching modules for psychotherapy training purposes
Efficient Deduplication and Leakage Detection in Large Scale Image Datasets with a focus on the CrowdAI Mapping Challenge Dataset
Recent advancements in deep learning and computer vision have led to
widespread use of deep neural networks to extract building footprints from
remote-sensing imagery. The success of such methods relies on the availability
of large databases of high-resolution remote sensing images with high-quality
annotations. The CrowdAI Mapping Challenge Dataset is one of these datasets
that has been used extensively in recent years to train deep neural networks.
This dataset consists of 280k training images and 60k testing
images, with polygonal building annotations for all images. However, issues
such as low-quality and incorrect annotations, extensive duplication of image
samples, and data leakage significantly reduce the utility of deep neural
networks trained on the dataset. Therefore, it is an imperative pre-condition
to adopt a data validation pipeline that evaluates the quality of the dataset
prior to its use. To this end, we propose a drop-in pipeline that employs
perceptual hashing techniques for efficient de-duplication of the dataset and
identification of instances of data leakage between training and testing
splits. In our experiments, we demonstrate that nearly 250k(90%)
images in the training split were identical. Moreover, our analysis on the
validation split demonstrates that roughly 56k of the 60k images also appear in
the training split, resulting in a data leakage of 93%. The source code used
for the analysis and de-duplication of the CrowdAI Mapping Challenge dataset is
publicly available at https://github.com/yeshwanth95/CrowdAI_Hash_and_search .Comment: 9 pages, 2 figure
Ptu-024 - photometric stereo reconstruction for surface analysis of mucosal tissue
This paper provides a novel approach for real-time detection of polyps. Using a photometric stereo sensor for endoscopy imaging in a porcine model, the 3D surface geometry of a porcine gut is recovered. Shape features are extracted from the 3D surface data and analysed to detect and identify regions that are locally spherical, suggestive of polyps to aid polyp detection
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