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Radiat Phys Chem Oxf Engl 1993 ; 209: 110965, 2023 Aug.
Article in English | MEDLINE | ID: covidwho-2291034

ABSTRACT

Chest X-ray imaging is the most common X-ray imaging method for diagnosing coronavirus disease. The thyroid gland is one of the most radiation-sensitive organs of the body, particularly in infants and children. Therefore, it must be protected during chest X-ray imaging. Yet, because it has benefits and drawbacks, using a thyroid shield as protection during chest X-ray imaging is still up for debate.Therefore, this study aims to clarify the need for using a protective thyroid shield during chest X-ray imaging. This study was performed using different dosimeters (silica beads as a thermoluminescent dosimeter and an optically stimulated luminance dosimeter) embedded in an adult male ATOM dosimetric phantom. The phantom was irradiated using a portable X-ray machine with and without thyroid shielding. The dosimeter readings indicated that a thyroid shield reduced the radiation dose to the thyroid gland by 69% ± 18% without degrading the obtained radiograph. The use of a protective thyroid shield during chest X-ray imaging is recommended because its benefits outweigh the risks.

2.
National Remote Sensing Bulletin ; 26(9):1777-1788, 2022.
Article in Chinese | Scopus | ID: covidwho-2145243

ABSTRACT

The COVID-19 epidemic swept the world and continued to spread. Without effective medical treatments and vaccine during the early stage of the pandemic, local governments in various countries had to lock down cities and adopt non-pharmaceutical interventions (NPIs), such as the stay-at-home order, social distancing, and so on. NPIs against the COVID-19 epidemic have significantly changed socioeconomic activities in cities. However, characteristics and patterns of urban socio-economic activities under this influence are still unclear. Benefiting from the development of earth observation technologies, such large-scale changes in socioeconomic activities are enough to be captured by satellites through remotely sensed night-time lights (NTL). In this study, we selected 20 major cities in the United States including New York, Chicago and Los Angeles to analyze spatio-temporal variations of NTL caused by the lockdown of cities. The first round of COVID-19 epidemic occurred in the United States in mid-March 2020. Since March 2020, American cities have successively issued stay-at-home orders, but there are differences in the time and strictness of policy implementation. Large cities have a higher population density and a higher intensity of social activities, so they are more susceptible to infectious diseases. The diversity of lockdown dates and strictness of lockdowns in cities in the United States are conducive to investigating the spatio-temporal variations of NTL. We acquired monthly averaged NPP VIIRS products of February, March and April, 2020, which are from Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) onboard the Suomi National Polar-orbiting Platform (NPP). We further analyzed the spatial pattern, distance decay and disparities in land use types of changes in NTL. Results show that NTL generally dimmed by 5-8% in U.S. cities caused by the lockdown of cities. There are 6 cities where the luminous brightness has dropped by more than 10%: Chicago, Dallas, Denver, Detroit, Minneapolis, and St. Louis. Among them, Minneapolis has the largest decrease in luminous brightness, with a decrease of about 40% in March. The spatial change of NTL shows obvious "core-periphery" pattern that the reduction of NTL declines with the distance from the city center. This is mainly because the central area of the city is a concentrated commercial area. After the closure of the city, commercial activities have dropped significantly, resulting in an obvious reduction in NTL around city centers. The reduction of NTL varies among diverse urban land use types. In New York, NTL decreased the most on land for residence and aviation facilities by 12% and 11%, respectively. In Chicago, NTL generally decreased by 20% in all types of urban land, and NTL recovered after one month of the lockdown of cities in other urban land except sports facilities land. This study only analyzes the spatio-temporal changes of NTL. In the future, it can be combined with multi-source data to explain the driving force of NTL changes. Nighttime light remote sensing effectively reflects urban socio-economic dynamics with an important application in monitoring and assessing socio-economic impacts of emergencies. © 2022 National Remote Sensing Bulletin. All rights reserved.

3.
Investigative Ophthalmology and Visual Science ; 63(7):379-F0210, 2022.
Article in English | EMBASE | ID: covidwho-2058220

ABSTRACT

Purpose : Dry age-related macular degeneration (AMD) is a leading contributor to visual impairment across the globe. No current treatment exists to improve visual function or reduce disease progression outside of vitamin supplementation and lifestyle changes. LIGHTSITE III is evaluating multiwavelength photobiomodulation (PBM) therapy using the LumiThera Valeda® Light Delivery System in dry AMD Methods : LIGHTSITE III (NCT04065490) is a prospective, double-masked, randomized, sham-controlled, parallel group, multi-center study to assess the safety and efficacy of PBM in dry AMD. Target enrollment was approximately 96 subjects (144 eyes). Subjects are treated with six series of PBM/Sham treatments (3x per week for 3 weeks) delivered over a 24-month period with a 13-month efficacy analysis of data. PBM therapy consists of low-level light exposure to selected tissues resulting in positive effects on mitochondrial output and improvement in cellular activity. Valeda is used to deliver multiwavelength PBM treatment using 590, 660 and 850 nm of light. Subjects are assessed for clinical and safety outcomes (i.e., best-corrected visual acuity (BCVA), low- luminance BCVA, contrast sensitivity, reading speed, color vision, VFQ-25 and perimetry). Independent OCT, FAF and color fundus imaging outcomes at selected timepoints are analyzed by a masked imaging reading center Results : A total of 148 eyes from 100 subjects with dry AMD have been enrolled and randomized in a 2:1 design (PBM:Sham). The majority of subjects are female (68%) and Caucasian (99%). The average age at enrollment was 75 years and mean time since dry AMD diagnosis is 4.9 years. COVID-19 interference has been minimal and not significantly impacted subject enrollment or retention. Clinical and anatomical outcome data from the interim analysis conducted at Month 13 is presented. Results from the 21-month time point are expected at end of 2022 Conclusions : LIGHTSITE III provides the largest, randomized controlled trial evaluating the effects of PBM in dry AMD subjects. PBM therapy may offer a new treatment strategy with a unique mechanism and modality for patients with dry AMD.

4.
18th IEEE International Colloquium on Signal Processing and Applications, CSPA 2022 ; : 1-4, 2022.
Article in English | Scopus | ID: covidwho-1922617

ABSTRACT

In this preliminary study, we compared Night Sky Brightness (NSB) in Shah Alam during the implementation of Movement Control Order (MCO) lockdown due to COVID-19 pandemic in June 2021 with the same duration in June 2020. Sky Quality Meter (SQM) was used to measure NSB in unit Magnitude per Square Arc Second (MSAS) while temperature was in Celsius and they were collected in Shah Alam, Selangor. The air quality information was obtained from the Malaysian AQI website. This project investigates the impact of economic and social activities during MCO lockdown to NSB, air pollution and temperature. Within the analysed time frame, the results indicate that there are some effects produced by MCO lockdown to the observed light or NSB, temperature and air pollution. On the average, the NSB, temperature and AQI have decreased by 0.25, 1.55 and 1.0, respectively. This shows that during the MCO lockdown, the air is cleaner and cooler;and the sky is darker which originates from improved air quality due to less air and road traffics;plus less industrial and human outdoor activities. © 2022 IEEE.

5.
2021 International Conference on Smart-Green Technology in Electrical and Information Systems, ICSGTEIS 2021 ; : 161-164, 2021.
Article in English | Scopus | ID: covidwho-1709097

ABSTRACT

This paper discusses an early investigation of the impact of the Covid-19 on the socio-economic activities by using the electricity consumption and the satellite nighttime light approach. This method was implemented in the island of Bali, a well-known tourism destination. The electricity consumption trend was investigated during a period of 2019-2020 and the result then was confirmed with the satellite image of nighttime light. The analysis results have shown that the declined electricity energy usage correlates with the reduced brightness level of the night time light. It was also found that the night time light image (NTL) from remote sensing data has successfully determined the areas with a significantly decreased socio-economic activities. In contrast, the image has also uncovered some areas with an increased in night time light brightness, which indicates an increased in socio-economic activities. © 2021 IEEE.

6.
J Pathol Inform ; 11: 23, 2020.
Article in English | MEDLINE | ID: covidwho-820011

ABSTRACT

Digital displays (monitors) are an indispensable component of a pathologists' daily workflow, from writing reports, viewing whole-slide images, or browsing the Internet. Due to a paucity of literature and experience surrounding display use and standardization in pathology, the Food and Drug Administration's (FDA) has currently restricted FDA-cleared whole-slide imaging systems to a specific model of display for each system, which at this time consists of only medical-grade (MG) displays. Further, given that a pathologists' display will essentially become their new surrogate "microscope," it becomes exceedingly important that all pathologists have a basic understanding of fundamental display properties and their functional consequences. This review seeks to: (a) define and summarize the current and emerging display technology, terminology, features, and regulation as they pertain to pathologists and review the current literature on the impact of different display types (e.g. MG vs. consumer off the shelf vs. professional grade) on pathologists' diagnostic performance and (b) discuss the impact of the recent digital pathology device componentization and the coronavirus disease 2019 public emergency on the pixel pathway and display use for remote digital pathology. Display technology has changed dramatically over the past 20 years and continues to change at a rapid rate. There is a paucity of published studies to date that investigate how display type affects pathologist performance, with more research necessary in order to develop standards and minimum specifications for displays in digital pathology. Given the complexity of modern displays, pathologists must become better informed regarding display technology if they wish to have more choice over their future "microscopes."

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