Granularity, also called peppering and multiple blue-gray dots, is defined as an accumulation of tiny, blue-gray granules in dermoscopy images. Granularity is most closely associated with a diagnosis of malignant melanoma. This study analyzes areas of granularity with color and texture measures to discriminate granularity in melanoma from similar areas in non-melanoma skin lesions. The granular areas in dermoscopy images of 74 melanomas and 14 melanomas in situ were identified and manually selected. For 200 non-melanoma dermoscopy images, those areas which most closely resembled granularity in color and texture were similarly selected. Ten texture and twenty-two color measures were studied. The texture measures consisted of the average and range of energy, inertia, correlation, inverse difference, and entropy. The color measures consisted of absolute and relative RGB averages, absolute and relative RGB chromaticity averages, absolute and relative G/B averages, CIE X, Y, Z, X/Y, X/Z and Y/Z averages, R variance, and luminance. These measures were calculated for each granular area of the melanomas and the comparable areas in the non-melanoma images. Receiver operating characteristic (ROC) curve analysis showed that the best separation of melanoma images from non-melanoma images by granular area features was obtained with a combination of color and texture measures. Comparison of ROC results showed greater separation of melanoma from benign lesions using relative color than using absolute color. Statistical analysis showed that the four most significant measures of granularity in melanoma are two color measures and two texture measures averaged over the spots: relative blue, relative green, texture correlation, and texture energy range. The best feature set, utilizing texture and relative color measures, achieved an accuracy of 96.4% based on area under the receiver operating characteristic curve.

ObjectiveTo determine the prevalence of nontherapeutic use of methylphenidate as well as to ascertain any benefits, side effects, and other factors associated with this use.Materials and MethodsA cross-sectional study was conducted in medical colleges in Pakistan using a self-constructed, validated questionnaire. The sample size was calculated using Open Source Statistics for Epidemiological Health software (OpenEpi web-based open-source program, MIT license), and it was determined to be 400. The type of sampling was cluster sampling. Cronbach's alpha was used to assess the internal consistency of the questionnaire, and it was found to be 0.80.ResultsOut of the 400 participants, 197 (49%) were male and 203 (51%) were female. The mean age of the participants was 21.02 (±1.54) years. Most of the participants (84%) reported they usually studied 1-3 hours a day, and 149 participants (37%) reported a score ranging from 70 to 80% in exams. Methylphenidate was admitted to be used by 37 participants. Out of these 37 participants, only 10 participants believed they had attention deficit hyperactivity disorder (ADHD). Participants revealed they used the drug to either cope with the anxiety related to their scores or merely as a personal, recreational choice. Methylphenidate was mostly acquired from peers (68%), and peer pressure was found to be a major factor in its misuse.ConclusionsMost of the methylphenidate misuse is linked to student underperformance in examinations and an underlying dissatisfaction. The problem is more aggravated when the social influence exerted by other students is taken into account. The side effects of drug usage are found to outweigh the benefits that have been reported.

Background Environmental surveillance (ES) for poliovirus is increasingly important for polio eradication, often detecting circulating virus before paralytic cases are reported. The sensitivity of ES depends on appropriate selection of sampling sites, which is difficult in low-income countries with informal sewage networks. Methods We measured ES site and sample characteristics in Nigeria during June 2018–May 2019, including sewage physicochemical properties, using a water-quality probe, flow volume, catchment population, and local facilities such as hospitals, schools, and transit hubs. We used mixed-effects logistic regression and machine learning (random forests) to investigate their association with enterovirus isolation (poliovirus and nonpolio enteroviruses) as an indicator of surveillance sensitivity. Results Four quarterly visits were made to 78 ES sites in 21 states of Nigeria, and ES site characteristic data were matched to 1345 samples with an average enterovirus prevalence among sites of 68% (range, 9%–100%). A larger estimated catchment population, high total dissolved solids, and higher pH were associated with enterovirus detection. A random forests model predicted “good” sites (enterovirus prevalence >70%) from measured site characteristics with out-of-sample sensitivity and specificity of 75%. Conclusions Simple measurement of sewage properties and catchment population estimation could improve ES site selection and increase surveillance sensitivity.

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Background: The right-sided aortic arch (RAA) is an uncommon anatomical anomaly found in <0.1% of the adult population. In this article, we report a case of RAA anomaly with an aberrant left subclavian artery (ALSA) and Kommerell’s diverticulum associated with aneurysmal dilation of the ascending aorta, left carotid artery (CCA) stenosis, and pancake kidney presented with a transient ischemic attack (TIA). To the best of our knowledge, this is the first case in the literature that discusses such associations, especially in a symptomatic patient with neurological rather than tracheaesophageal symptoms and in the absence of the steal phenomenon. Case Description: A 52-year-old male, with a history of recurrent multiple TIAs, presented immediately after the onset of blurred vision and left-sided weakness. The initial diagnostic cerebral angiogram revealed a left CCA stenosis of <30%, with normal posterior circulation vasculature. The diagnosis of RAA was made with computed tomography angiography (CTA) of the thoracic and abdominal aorta, which revealed Type 2 RAA, with ALSA, which had a bullous dilatation at its origin that suggests Kommerell’s diverticulum. Another two findings on CTA were a persistent left-sided superior vena cava that ended in the coronary sinus and a single pelvic fused renal mass (Pancake kidney). Conclusion: We presented an extremely rare case of RAA with ALSA associated with a group of extra rare anomalies. Understanding the anatomical variants of RAA and its characteristics is critical to improving the management and follow-up of patients with such anomalies.

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