With recent advances in millimeter-wave technology, including the availability of high-power sources in this band, it has become necessary to understand the biological implications of this energy for human beings. This paper gives the millimeter-wave absorption efficiency for the human body with and without clothing. Ninety to ninety-five percent of the incident energy may be absorbed in the skin with dry clothing, with or without an intervening air gap, acting as an impedance transformer. On account of the submillimeter depths of penetration in the skin, superficial SAR'S as high as 65-357 W/Kg have been calculated for power density of incident radiation corresponding to the ANSI guideline of 5 mW/cm2. Becanse most of the millimeter-wave absorption is in the region of the cutaneous thermal receptors (O.1-1.0 mm), the sensations of absorbed energy are likely to be similar to those of IR. For the latter, threshold of heat perception is near 0.67 mW/cm2, with power densities on the order of 8.7 mW/cm2 likely to cause sensations of "very warm to hot" with a latency of 1.0+ 0.6 s. Calculations are made for thresholds of hearing of pulsed millimeter waves. Pulsed energy densities of 143-579 pJ/cm2 are obtained for the frequency band 30-300 GHz. These are 8-28 times larger than the threshold for microwaves below 3 GHz. The paper also points to the need for evaluation of ocular effects of millimeter-wave irradiation because of high SAR'S in the cornea.
ProposeA qualitative approach using semi-structured individual interviews was used to elicit common outdoor difficulties in individuals with visual impairment.MethodsInterviews were recorded and then transcribed verbatim into text for thematic analysis. Twenty legally-blind individuals aged 34.25 ± 2.41 years with different etiologies were included in this study.ResultsAll participants had experienced some sort of difficulty in outdoor environments. The most important problems as perceived by the participants are installation of tactile ground surface indicators, unsafe sidewalks, existence of obstacles on sidewalks, difficulty reading bus numbers, disorientation, fear of falling, recognition of faces, inability to read street names, the presence of spaces between platforms and buses, walking into glass doors, crossing streets, and the risk of Arial barriers.ConclusionsAs a visually impaired person might say, sidewalks can be the most dangerous of places. Appropriate urban modification can be very beneficial.
The aim was to evaluate the impact of saffron supplementation on visual function in patients with dry age-related macular degeneration (ARMD). Fifty-four participants, 23 male and 31 female, with dry ARMD were assigned to one of the following two groups. The treatment group (n=29) consumed 50 mg saffron daily during a 3- month period, while 25 subjects served as the control group. Visual acuity, contrast sensitivity, and retinal thickness were measured at the beginning and at the end of the study. Quality of life was evaluated using the Melbourne Low Vision Index (MLVI) before and after treatment. Significant increases in visual acuity and contrast sensitivity were found in the saffron group but not in the control group. Changes in macular thickness were not statistically different between the two groups. Short-term consumption of saffron may slow down the progression of disease and improve visual function, especially contrast sensitivity, in patients with dry ARMD.
PurposeThe purpose of this paper is to provide an evidence‐base for home modification guidelines for people with visual impairment due to age‐related macular degeneration (AMD), from the perspective of people with AMD, by exploring the home modifications they find useful and would recommend to other people with visual impairment due to AMD as being effective.Design/methodology/approachPeople with impairments may not be aware of their own coping with inability strategies until they are asked to express their strategies. A qualitative approach using semi‐structured individual interviews was used to elicit the perspectives of people with AMD with regards to their preferred home modification interventions. Interviews were recorded and then transcribed verbatim into text for thematical analysis using Nvivo 8.FindingsIn total, 31 individuals (aged 79.1±5.6 years) with AMD and no other ocular diseases were recruited from a low vision clinic or the Macular Degeneration Foundation database in a metropolitan city. Interviewees had not received any formal home modification assessment from a government provider. Nevertheless, 70 per cent of participants stated that they undertook home modifications themselves or with the assistance of family and friends. The most important functional modifications as perceived by the participants concerned the installation of hand rails, non‐slip matting, colour contrasting safety stair nosing, single lever taps, slip resistant flooring, lift chairs and motion sensors that activated pathway lighting. Kitchens, steps and bathrooms were perceived as hazardous locations. Most participants had difficulties with reading fine‐print material on kitchen appliances, washing machines, microwave ovens and remote controls for electronic devices in the home.Originality/valueAn evidence‐base for useful home modifications as suggested by people with visual impairment was perceived to be a valuable resource for other people with visual impairment who may not yet have developed adaptive strategies. Industrial and interior designers and low vision rehabilitation services who aim to improve functionality of the home environment will also find these suggestions useful.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.