Vision-Based Mobile Robotic Platform for Autonomous Landing of Quadcopters

This project deals with the development of a vision-based control algorithm to assist quadcopters in the landing process. For demonstration purposes, the approach has been implemented in a mobile robotic platform (turtlebot). In this project, the objective is to use the mobile robot as a landing platform. The camera on-board the mobile robot detects the quadcopter (AprilTag attached to the flying robot) and keeps track of it. Based on this idea, the proposed approach estimates in real-time the landing zone. Once this zone is calculated, the mobile robot moves towards this area, stops under the quadcopter, and acts as a landing pad. Similarly, this approach can be implemented on the quadcopter to autonomously help in its landing process. The system does not only see possible usage in defense and protection of military combatants, but also in further development of communications systems between Unmanned Aerial Vehicles (UAVs) and other robotics systems

The epidemiology of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional condition of the bowel that is diagnosed using clinical criteria. This paper discusses the nature of the diagnostic process for IBS and how this impacts epidemiological measurements. Depending on the diagnostic criteria employed, IBS affects around 11% of the population globally. Around 30% of people who experience the symptoms of IBS will consult physicians for their IBS symptoms. These people do not have significantly different abdominal symptoms to those who do not consult, but they do have greater levels of anxiety and lower quality of life. Internationally, there is a female predominance in the prevalence of IBS. There is 25% less IBS diagnosed in those over 50 years and there is no association with socioeconomic status. IBS aggregates within families and the genetic and sociological factors potentially underlying this are reviewed. Patients diagnosed with IBS are highly likely to have other functional disease and have more surgery than the general population. There is no evidence that IBS is associated with an increased mortality risk. The epidemiological evidence surrounding these aspects of the natural history is discussed

A comparison of the recording of comorbidity in primary and secondary care by using the Charlson Index to predict short-term and long-term survival in a routine linked data cohort

OBJECTIVE: Hospital admission records provide snapshots of clinical histories for a subset of the population admitted to hospital. In contrast, primary care records provide continuous clinical histories for complete populations, but might lack detail about inpatient stays. Therefore, combining primary and secondary care records should improve the ability of comorbidity scores to predict survival in population-based studies, and provide better adjustment for case-mix differences when assessing mortality outcomes. DESIGN: Cohort study. SETTING: English primary and secondary care 1 January 2005 to 1 January 2010. PARTICIPANTS: All patients 20 years and older registered to a primary care practice contributing to the linked Clinical Practice Research Datalink from England. OUTCOME: The performance of the Charlson index with mortality was compared when derived from either primary or secondary care data or both. This was assessed in relation to short-term and long-term survival, age, consultation rate, and specific acute and chronic diseases. RESULTS: 657,264 people were followed up from 1 January 2005. Although primary care recorded more comorbidity than secondary care, the resulting C statistics for the Charlson index remained similar: 0.86 and 0.87, respectively. Higher consultation rates and restricted age bands reduced the performance of the Charlson index, but the index's excellent performance persisted over longer follow-up; the C statistic was 0.87 over 1 year, and 0.85 over all 5 years of follow-up. The Charlson index derived from secondary care comorbidity had a greater effect than primary care comorbidity in reducing the association of upper gastrointestinal bleeding with mortality. However, they had a similar effect in reducing the association of diabetes with mortality. CONCLUSIONS: These findings support the use of the Charlson index from linked data and show that secondary care comorbidity coding performed at least as well as that derived from primary care in predicting survival

Comorbidities affect risk of nonvariceal upper gastrointestinal bleeding

Background & Aims The incidence of upper gastrointestinal bleeding (GIB) has not been reduced despite the decreasing incidence of peptic ulcers, strategies to eradicate Helicobacter pylori infection, and prophylaxis against ulceration from nonsteroidal anti-inflammatory drugs. Other factors might therefore be involved in the pathogenesis of GIB. Patients with GIB have increasing nongastrointestinal comorbidity, so we investigated whether comorbidity itself increased the risk of GIB. Methods We conducted a matched case-control study using linked primary and secondary care data collected in England from April 1, 1997 through August 31, 2010. Patients older than 15 years with nonvariceal GIB (n = 16,355) were matched to 5 controls by age, sex, year, and practice (n = 81,636). All available risk factors for GIB were extracted and modeled using conditional logistic regression. Adjusted associations with nongastrointestinal comorbidity, defined using the Charlson Index, were then tested and sequential population attributable fractions calculated. Results Comorbidity had a strong graded association with GIB; the adjusted odds ratio for a single comorbidity was 1.43 (95% confidence interval [CI]: 1.35–1.52) and for multiple or severe comorbidity was 2.26 (95% CI: 2.14%–2.38%). The additional population attributable fraction for comorbidity (19.8%; 95% CI: 18.4%–21.2%) was considerably larger than that for any other measured risk factor, including aspirin or nonsteroidal anti-inflammatory drug use (3.0% and 3.1%, respectively). Conclusions Nongastrointestinal comorbidity is an independent risk factor for GIB, and contributes to a greater proportion of patients with bleeding in the population than other recognized risk factors. These findings could help in the assessment of potential causes of GIB, and also explain why the incidence of GIB remains high in an aging population

Dynamic Analysis of Executables to Detect and Characterize Malware

It is needed to ensure the integrity of systems that process sensitive information and control many aspects of everyday life. We examine the use of machine learning algorithms to detect malware using the system calls generated by executables-alleviating attempts at obfuscation as the behavior is monitored rather than the bytes of an executable. We examine several machine learning techniques for detecting malware including random forests, deep learning techniques, and liquid state machines. The experiments examine the effects of concept drift on each algorithm to understand how well the algorithms generalize to novel malware samples by testing them on data that was collected after the training data. The results suggest that each of the examined machine learning algorithms is a viable solution to detect malware-achieving between 90% and 95% class-averaged accuracy (CAA). In real-world scenarios, the performance evaluation on an operational network may not match the performance achieved in training. Namely, the CAA may be about the same, but the values for precision and recall over the malware can change significantly. We structure experiments to highlight these caveats and offer insights into expected performance in operational environments. In addition, we use the induced models to gain a better understanding about what differentiates the malware samples from the goodware, which can further be used as a forensics tool to understand what the malware (or goodware) was doing to provide directions for investigation and remediation.Comment: 9 pages, 6 Tables, 4 Figure

Pavement Evaluation of the Concrete Tie-bars and Dowel Baskets on Irvin Cobb Drive, US 60, McCracken County, KY

A 1500 Mhz. ground coupled, ground penetrating radar antenna was used to identify both the horizontal alignment and the vertical displacement of the concrete tie-bars and the transverse joint dowel bar assembles on a Portland-Cement-Concrete-Pavement (PCCP) on US 60 in McCracken County, KY. Approximately 5 lanes miles of PCCP were evaluated using the 1500 Mhz. ground coupled antenna. Results indicate that only one transverse dowel basket out of an approximate total of 1,760 were within 4.17 inches of the pavement surface. Seven transverse dowel baskets were misaligned four inches or greater from the location of the sawed joint. These areas represent 0.45 percent of the total transverse joints on the project. The ground penetrating radar results also indicated there were no areas along the longitudinal joint where the tie-bars were either too close to the pavement surface or missing

Incidence and prevalence of celiac disease and dermatitis herpetiformis in the UK over two decades: population-based study

OBJECTIVES: Few studies have quantified the incidence and prevalence of celiac disease (CD) and dermatitis herpetiformis (DH) nationally and regionally by time and age groups. Understanding this epidemiology is crucial for hypothesizing about causes and quantifying the burden of disease. METHODS: Patients with CD or DH were identified in the Clinical Practice Research Datalink between 1990 and 2011. Incidence rates and prevalence were calculated by age, sex, year, and region of residence. Incidence rate ratios (IRR) adjusted for age, sex, and region were calculated with Poisson regression. RESULTS: A total of 9,087 incident cases of CD and 809 incident cases of DH were identified. Between 1990 and 2011, the incidence rate of CD increased from 5.2 per 100,000 (95% confidence interval (CI), 3.8-6.8) to 19.1 per 100,000 person-years (95% CI, 17.8-20.5; IRR, 3.6; 95% CI, 2.7-4.8). The incidence of DH decreased over the same time period from 1.8 per 100,000 to 0.8 per 100,000 person-years (average annual IRR, 0.96; 95% CI, 0.94-0.97). The absolute incidence of CD per 100,000 person-years ranged from 22.3 in Northern Ireland to 10 in London. There were large regional variations in prevalence for CD but not DH. CONCLUSIONS: We found a fourfold increase in the incidence of CD in the United Kingdom over 22 years, with large regional variations in prevalence. This contrasted with a 4% annual decrease in the incidence of DH, with minimal regional variations in prevalence. These contrasts could reflect differences in diagnosis between CD (serological diagnosis and case finding) and DH (symptomatic presentation) or the possibility that diagnosing and treating CD prevents the development of DH

Inflammatory pseudotumor of the Kidney

<p>Abstract</p> <p>Background</p> <p>Inflammatory pseudotumor of the kidney or inflammatory myofibroblastic tumor (IMT) is composed of spindle cells admixed with variable amount of proliferating myofibroblasts, fibroblasts, extracellular collagen, lymphocytes and plasma cells. This mainly affects the urinary bladder or prostate. Renal involvement is rare.</p> <p>Case presentation</p> <p>A 56 year-old man was diagnosed with asymptomatic left sided hydronephrosis while being investigated for rheumatoid arthritis. CT scan imaging showed ill defined fascial plains around the kidney and thickening around the renal hilum suggestive of localized inflammatory change. Worsening intermittent left loin pain with increasing hydronephrosis, significant cortical thinning and marked deterioration of renal function necessitated nephrectomy. Macroscopy showed a hydronephrotic fibrotic kidney with microscopy and immunohistochemistry consistent with a histological diagnosis of IMT.</p> <p>Conclusion</p> <p>We report a case of an inflammatory pseudotumor of the kidney. It is unique in that the patient presented with painless hydronephrosis followed two years later with progressive deterioration in renal function and worsening loin pain.</p

Change in quality of life for patients with irritable bowel syndrome following referral to a gastroenterologist: a cohort study

BACKGROUND: Irritable bowel syndrome (IBS), a chronic functional condition, considerably reduces quality of life (QoL) and referral to gastroenterology is common. Until now, however, the impact of seeing a gastroenterologist for IBS on patients’ QoL and utility has not been assessed.METHODS: Patients referred with “probable IBS” to the Nottingham Treatment Centre between October 2012 and March 2014 were invited to complete a QoL questionnaire (EuroQol–5 Dimension) before their first appointment. Patients with confirmed IBS who completed this baseline assessment were sent follow-up questionnaires three and twelve months later. Global QoL and utility were measured at each time point and change from baseline calculated. Paired t-tests analysed the significance of any change. RESULTS: Of 205 invited patients, 69 were eligible and recruited. Response at three and twelve months was 45% and 17% respectively. Median global QoL at baseline was 67.5 (Interquartile range [IQR] 50.0 to 80.0), with a mean increase of 3.25 (95% confidence interval [CI] -5.38 to 11.88) three months later and a mean decrease of -1.82 (95% CI -16.01 to 12.38) after one year. The median utility at baseline was 0.76 (IQR 0.69 to 0.80), with a mean increase of 0.06 (95%CI -0.01 to 0.14) at three months and no change, 0.00 (-0.16 to 0.16), after one year. CONCLUSION: Patients experienced a small but not statistically significant increase in QoL and utility three months after seeing a gastroenterologist for IBS, which was not maintained. Gastroenterology referral does not appear to appreciably improve Qol for most people with IBS

The risk of unexpected hospital admissions and primary care visits after an elective day-case gastroscopy: A cohort study within England

Aim: To determine the excess of acute medical contacts following a day-case diagnostic gastroscopy. Methods: Cohort study using English linked primary, secondary care and death registry electronic health data. We included 277,535 diagnostic day-case gastroscopies in 225,304 people between 1998 and 2016 and followed up for 30 days. 1,383,535 30-day periods without a gastroscopy within 991,249 people frequency matched on year, gender and decade of birth. Non-cancer deaths, emergency non-cancer admissions and cardio, vascular or respiratory (CVR) primary care consultations were identified and adjusted for each other as competing risks. Outcomes related to possible indications for gastroscopy were censored. Results: 5.1% of day-case diagnostic gastroscopies were followed by emergency hospital admission, 0.4% for a CVR diagnosis. Adjusted for age, sex, morbidity, time trends, indications and competing risks, there was a 0.1% excess of CVR-related hospital admissions compared to controls. This reduced to 0.05% (95% confidence interval 0.04–0.06%) in people under 40 years without morbidity and increased to 1.1% (0.6%–1.6%) in people over 90 years with high comorbidity. Similarly, by 30 days, 3.8% had a primary care consultation for a CVR problem, with an excess after adjustment ranging from 0.13% (0.11%–0.16%) to 0.31% (0.14%–0.50%). Overall numbers needed to harm ranged from 1 in 294 gastroscopies to 1 in 67 gastroscopies. Conclusions: There was an excess of vascular and respiratory events associated with a diagnostic gastroscopy. In younger patients, this risk manifested as an increase in primary care consultations while in older patients there was an increase in emergency hospital admissions