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2.
IEEE Trans Neural Netw Learn Syst ; 32(10): 4278-4290, 2021 10.
Article in English | MEDLINE | ID: covidwho-1455467

ABSTRACT

This article devises a photograph-based monitoring model to estimate the real-time PM2.5 concentrations, overcoming currently popular electrochemical sensor-based PM2.5 monitoring methods' shortcomings such as low-density spatial distribution and time delay. Combining the proposed monitoring model, the photographs taken by various camera devices (e.g., surveillance camera, automobile data recorder, and mobile phone) can widely monitor PM2.5 concentration in megacities. This is beneficial to offering helpful decision-making information for atmospheric forecast and control, thus reducing the epidemic of COVID-19. To specify, the proposed model fuses Information Abundance measurement and Wide and Deep learning, dubbed as IAWD, for PM2.5 monitoring. First, our model extracts two categories of features in a newly proposed DS transform space to measure the information abundance (IA) of a given photograph since the growth of PM2.5 concentration decreases its IA. Second, to simultaneously possess the advantages of memorization and generalization, a new wide and deep neural network is devised to learn a nonlinear mapping between the above-mentioned extracted features and the groundtruth PM2.5 concentration. Experiments on two recently established datasets totally including more than 100 000 photographs demonstrate the effectiveness of our extracted features and the superiority of our proposed IAWD model as compared to state-of-the-art relevant computing techniques.


Subject(s)
Deep Learning , Environmental Monitoring/methods , Particle Size , Algorithms , COVID-19/prevention & control , Databases, Factual , Humans , Nonlinear Dynamics , Particulate Matter , Photography , SARS-CoV-2
3.
Sensors (Basel) ; 21(17)2021 Aug 25.
Article in English | MEDLINE | ID: covidwho-1379985

ABSTRACT

The emergence of various types of commercial cameras (compact, high resolution, high angle of view, high speed, and high dynamic range, etc.) has contributed significantly to the understanding of human activities. By taking advantage of the characteristic of a high angle of view, this paper demonstrates a system that recognizes micro-behaviors and a small group discussion with a single 360 degree camera towards quantified meeting analysis. We propose a method that recognizes speaking and nodding, which have often been overlooked in existing research, from a video stream of face images and a random forest classifier. The proposed approach was evaluated on our three datasets. In order to create the first and the second datasets, we asked participants to meet physically: 16 sets of five minutes data from 21 unique participants and seven sets of 10 min meeting data from 12 unique participants. The experimental results showed that our approach could detect speaking and nodding with a macro average f1-score of 67.9% in a 10-fold random split cross-validation and a macro average f1-score of 62.5% in a leave-one-participant-out cross-validation. By considering the increased demand for an online meeting due to the COVID-19 pandemic, we also record faces on a screen that are captured by web cameras as the third dataset and discussed the potential and challenges of applying our ideas to virtual video conferences.


Subject(s)
Human Activities , Photography , COVID-19 , Humans , Pandemics
6.
Sensors (Basel) ; 20(21)2020 Oct 29.
Article in English | MEDLINE | ID: covidwho-1308410

ABSTRACT

Determining body composition via mobile application may circumvent limitations of conventional methods. However, the accuracy of many technologies remains unknown. This investigation assessed the convergent and concurrent validity of a mobile application (LS) that employs 2-dimensional digital photography (LS2D) and 3-dimensional photonic scanning (LS3D). Measures of body composition including circumferences, waist-to-hip ratio (WHR), and body fat percentage (BF%) were obtained from 240 healthy adults using LS and a diverse set of conventional methods-Gulick tape, bioelectrical impedance analysis (BIA), and skinfolds. Convergent validity was consistently high-indicating these methods vary proportionally and can thus reliably detect changes despite individual measurement differences. The span of the Limits of Agreement (LoA) using LS were comparable to the LoA between conventional methods. LS3D exhibited high agreement relative to Gulick tape in the measurement of WHR, despite poor agreement with individual waist and hip circumferences. In BF%, LS2D exhibited high agreement with BIA and skinfold methods, whereas LS3D demonstrated low agreement. Interestingly, the low inferred bias between LS3D and DXA using existing data suggests that LS3D may have high agreement with dual-energy x-ray absorptiometry. Overall, the suitability of LS2D and LS3D to replace conventional methods must be based on an individual user's criteria.


Subject(s)
Anthropometry/methods , Body Composition , Mobile Applications , Absorptiometry, Photon , Adipose Tissue , Adult , Electric Impedance , Humans , Photography
7.
Vet Rec ; 188(8): 290-291, 2021 Apr.
Article in English | MEDLINE | ID: covidwho-1287408

ABSTRACT

Georgina Mills introduces the winners of this year's BVA Veterinary Photographer of the Year competition.


Subject(s)
Awards and Prizes , Photography , Veterinary Medicine , Animals , COVID-19 , Happiness , Humans , Pets/psychology , Quarantine , United Kingdom/epidemiology
8.
Cornea ; 40(12): 1639-1643, 2021 Dec 01.
Article in English | MEDLINE | ID: covidwho-1281892

ABSTRACT

PURPOSE: Proctored surgical instruction has traditionally been taught through in-person interactions in either the operating room or an improvised wet lab. Because of the COVID-19 pandemic, live in-person instruction was not feasible owing to social distancing protocols, so a virtual wet lab (VWL) was proposed and implemented. The purpose of this article is to describe our experience with a VWL as a Descemet membrane endothelial keratoplasty (DMEK) skills-transfer course. This is the first time that a VWL environment has been described for the instruction of ophthalmic surgery. METHODS: Thirteen participant surgeons took part in VWLs designed for DMEK skills transfer in September and October 2020. A smartphone camera adapter and a video conference software platform were the unique media for the VWL. After a didactic session, participants were divided into breakout rooms where their surgical scope view was broadcast live, allowing instructors to virtually proctor their participants in real time. Participants were surveyed to assess their satisfaction with the course. RESULTS: All (100%) participants successfully injected and unfolded their DMEK grafts. Ten of the 13 participants completed the survey. Respondents rated the experience highly favorably. CONCLUSIONS: With the use of readily available technology, VWLs can be successfully implemented in lieu of in-person skills-transfer courses. Further development catering to the needs of the participant might allow VWLs to serve as a viable option of surgical education, currently limited by geographical and social distancing boundaries.


Subject(s)
Descemet Stripping Endothelial Keratoplasty/education , Photography/instrumentation , SARS-CoV-2 , Smartphone/instrumentation , Video-Assisted Surgery/education , Videoconferencing/instrumentation , COVID-19/epidemiology , Computer Systems , Humans , Ophthalmologists/education , Software , Surveys and Questionnaires , User-Computer Interface
10.
J Am Geriatr Soc ; 69(5): 1181-1182, 2021 05.
Article in English | MEDLINE | ID: covidwho-1232318
12.
Indian J Ophthalmol ; 69(5): 1271-1274, 2021 May.
Article in English | MEDLINE | ID: covidwho-1207859

ABSTRACT

Purpose: The aim of this work was to study and document retinal changes in coronavirus disease-2019 (COVID-19) positive patients with nonsevere disease using a nonmydriatic handheld fundus camera. Methods: A cross-sectional observational study was conducted on patients affected by COVID-19 who were admitted at our center. Our study included patients with no, mild, and moderate symptoms (nonsevere cases). Intensive care unit (ICU)-admitted patients were excluded considering the difficulty in procuring the fundus image by the handheld camera due to patients positioning. Patients with systemic conditions (diabetes, hypertension, and severe anemia) known to cause retinopathy were also excluded. Bedside anterior segment examination, fundus examination using indirect ophthalmoscopy and fundus imaging of each patient using a nonmydriatic handheld fundus camera was done by a trained ophthalmologist posted for COVID duty. Results: In a cohort of 138 patients, 94 (68.1%) were men and 44 (31.9%) were women. A total of 276 eyes were evaluated. The mean age of the patients was 38.51 ± 14.4 years. Anterior segment evaluation showed no abnormality in any of the eyes. On fundus screening using nonmydriatic handheld camera, a single streak of superficial retinal hemorrhage was noted at the posterior pole of the fundus in the left eye of one patient (0.72%), which was away from fovea. Laboratory tests revealed low hemoglobin (between 10 and 10.9 g/dL falling under mild Anemia) in 12 patients, elevated total leucocyte count in 6 patients, raised LDH in majority of patients (323 ± 101 Units/L) and elevated CRP (14.6 ± 30.99 mg/L). Rest of the lab parameters were within the normal range. Conclusion: In our study, COVID patients with mild-to-moderate symptoms did not show any inflammatory/infective or vaso-occlusive lesions in the retina attributable to COVID-19 infection, except one patient who had a single streak hemorrhage in the macula away from fovea, probably incidental.


Subject(s)
COVID-19 , Photography , Adult , Cross-Sectional Studies , Female , Fundus Oculi , Humans , Male , Middle Aged , SARS-CoV-2 , Young Adult
13.
Recenti Prog Med ; 112(4): 321-322, 2021 04.
Article in Italian | MEDLINE | ID: covidwho-1194518
14.
Clin Orthop Relat Res ; 479(10): 2228-2235, 2021 10 01.
Article in English | MEDLINE | ID: covidwho-1161062

ABSTRACT

BACKGROUND: Teleradiology has become one of the most important approaches to virtual clinical diagnosis; its importance has only grown during the coronavirus 2019 pandemic. In developing countries, asking patients to take photographs of their images using a smartphone can facilitate the process and help keep its costs down. However, the images taken by patients with smartphones often are of poor quality, and there is no regulation or standard instruction about how to use smartphones to take photographs of medical examination images effectively. These problems limit the use of smartphones in remote diagnosis and treatment. QUESTIONS/PURPOSES: To formulate a set of guidelines for the most appropriate and effective use of smartphones to capture images (radiographs, CT images, and MR images), and to determine whether these guidelines are more effectively adopted by patients of differing ages and genders. METHODS: In this prospective study, a set of step-by-step instructions was created with the goal of helping patients take better smartphone photographs of orthopaedic diagnostic images for transfer to telemedicine services. Following the advice of surgeons, experts in smartphone technology, imaging experts, and suggestions from patients, the instructions were modified based on clinical experience and finalized with the goals of simplicity, clarity, and convenience. Potentially eligible patients were older than 18 years, had no cognitive impairment, and used smart phones. Based on that, 256 participants (patients or their relatives and friends) who visited the orthopaedic department of our hospital from June to October 2020 potentially qualified for this study. A total of 11% (29) declined to participate, leaving 89% (227) for analysis here. Their mean age was 36 ± 11 years, 50% were women (113 of 227), and the patient himself/herself represented in 34% (78 of 227) of participants while relatives or friends of patients made up 66% (149 of 227) of the group. In this study, the diagnoses included spinal stenosis (47% [107 of 227]), disc herniation without spinal stenosis (31% [71 of 227]), vertebral fractures (14% [32 of 227]), and other (7% [17 of 227]). Each study participant first took photographs of their original medical images based on their own knowledge of how to use the smartphone camera function; each participant then took pictures of their original images again after receiving our instructional guidance. Three senior spine surgeons (YZ, TQL, TCM) in our hospital analyzed, in a blinded manner, the instructed and uninstructed imaging files based on image clarity (the content of the image is complete, the text information in the image is clearly visible, there is neither reflection nor shadow in the image) and image position (it is not tilted, curled, inverted, or reversed). If either of these conditions was not satisfied, the picture quality was deemed unacceptable; two of three judges' votes determined the outcome. Interobserver reliability with kappa values for the three judges were 0.89 (YZ versus TQL), 0.92 (YZ versus TCM), and 0.90 (TQL versus TCM). RESULTS: In this study, the overall proportion of smartphone medical images deemed satisfactory increased from 40% (91 of 227) for uninstructed participants to 86% (196 of 227) for instructed participants (risk ratio 2.15 [95% CI 1.82 to 2.55]; p<0.001). The proportion of acceptable-quality images in different age groups improved after instruction, except for in patients aged 51 years or older (3 of 17 uninstructed participants versus 8 of 17 instructed participants; RR 2.67 [95% CI 0.85 to 8.37]; p = 0.07). The proportion of acceptable-quality images in both genders improved after instruction, but there was no difference between the genders. CONCLUSION: We believe our guidelines for patients who wish to take smartphone photographs of their medical images will decrease image transmission cost and facilitate orthopaedic telemedicine consultations. However, it appears that patients older than 50 years are more likely to have difficulty with this approach, and if so, they may benefit from more hands-on assistance from clinic staff or younger relatives or friends. The degree to which our findings are culture-specific should be verified by other studies in other settings, but on the face of it, there is little reason to believe our findings would not generalize to a reasonable degree. Other studies in more heterogeneous populations should also evaluate factors related to levels of educational attainment and wealth differences, but in the meantime, our findings can give clinical teams an idea of which patients may need a little extra assistance. LEVEL OF EVIDENCE: Level II, therapeutic study.


Subject(s)
Diagnostic Imaging/standards , Photography/standards , Smartphone/standards , Teleradiology/standards , Adult , COVID-19 , Female , Humans , Male , Middle Aged , Pandemics , Prospective Studies , SARS-CoV-2
17.
PLoS One ; 16(2): e0247440, 2021.
Article in English | MEDLINE | ID: covidwho-1102385

ABSTRACT

The purpose of this work is to provide an effective social distance monitoring solution in low light environments in a pandemic situation. The raging coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus has brought a global crisis with its deadly spread all over the world. In the absence of an effective treatment and vaccine the efforts to control this pandemic strictly rely on personal preventive actions, e.g., handwashing, face mask usage, environmental cleaning, and most importantly on social distancing which is the only expedient approach to cope with this situation. Low light environments can become a problem in the spread of disease because of people's night gatherings. Especially, in summers when the global temperature is at its peak, the situation can become more critical. Mostly, in cities where people have congested homes and no proper air cross-system is available. So, they find ways to get out of their homes with their families during the night to take fresh air. In such a situation, it is necessary to take effective measures to monitor the safety distance criteria to avoid more positive cases and to control the death toll. In this paper, a deep learning-based solution is proposed for the above-stated problem. The proposed framework utilizes the you only look once v4 (YOLO v4) model for real-time object detection and the social distance measuring approach is introduced with a single motionless time of flight (ToF) camera. The risk factor is indicated based on the calculated distance and safety distance violations are highlighted. Experimental results show that the proposed model exhibits good performance with 97.84% mean average precision (mAP) score and the observed mean absolute error (MAE) between actual and measured social distance values is 1.01 cm.


Subject(s)
COVID-19/prevention & control , Deep Learning , Physical Distancing , Humans , Light , Pandemics , Photography/instrumentation
18.
Acta Diabetol ; 57(12): 1493-1499, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-1064509

ABSTRACT

AIMS: To evaluate diabetic retinopathy (DR) screening with a portable handheld smartphone-based retinal camera and telemedicine in an urban primary healthcare setting and to evaluate the learning curve for image acquisition, performed by healthcare personnel without previous experience in retinal imaging. METHODS: This was a prospective study that enrolled patients with type 2 diabetes mellitus (T2DM) followed at a primary healthcare unit in São Paulo, Brazil. After a brief training in image acquisition, there was further continuous feedback given by a retina specialist during the remote image reading process. Each patient underwent two fundus and one anterior ocular segment images per eye, after mydriasis. Patients were classified according to the need of referral. RESULTS: A total of 627 adult individuals with T2DM underwent retinal evaluation. The population was composed by 63.2% female individuals, age median of 66 years, diabetes duration 10.7 ± 8.2 years and HbA1c 7.7 ± 1.9% (61 + 20.8 mmol/mol). The most prevalent associated comorbidities were arterial hypertension (80.3%) and dyslipidemia (50.2%). Referral decision was possible in 81.2% patients. Most patients had absent or non-referable DR; the main ocular media opacity detected was cataract. After the 7th day of image acquisition, the daily rate of patients whose images allowed clinical decision was maintained above 80%. A higher HbA1c was associated with referable DR. CONCLUSIONS: A low-cost DR screening strategy with a handheld device and telemedicine is feasible and has the potential to increase coverage of DR screening in underserved areas; the possibility of mobile units is relevant for DR screening in the context of COVID-19 pandemic. Daily rate of patients whose examinations allowed clinical decision. X-axis: day of examination; Y-axis: rate (%) of patients whose examinations allowed a clinical decision.


Subject(s)
Diabetic Retinopathy/diagnosis , Mass Screening/methods , Photography/methods , Retina/diagnostic imaging , Telemedicine/methods , Adult , Aged , Brazil , COVID-19 , Coronavirus Infections/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetic Retinopathy/diagnostic imaging , Female , Humans , Male , Mass Screening/instrumentation , Middle Aged , Pandemics , Pneumonia, Viral/epidemiology , Prevalence , Primary Health Care/methods , Prospective Studies , Referral and Consultation , Smartphone , Telemedicine/instrumentation
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