To determine if 'Defocus Incorporated Multiple Segments' (DIMS) spectacle lenses slow childhood myopia progression.
A 2-year double-masked randomised controlled trial was carried out in 183 Chinese ...children aged 8-13 years, with myopia between -1.00 and -5.00 D and astigmatism ≤1.50 D. Children were randomly assigned to wear DIMS (n=93) or single vision (SV) spectacle lenses (n=90). DIMS lens incorporated multiple segments with myopic defocus of +3.50 D. Refractive error (cycloplegic autorefraction) and axial length were measured at 6month intervals.
160 children completed the study, n=79 in the DIMS group and n=81 in the SV group. Average (SE) myopic progressions over 2 years were -0.41±0.06 D in the DIMS group and -0.85±0.08 D in the SV group. Mean (SE) axial elongation was 0.21±0.02 mm and 0.55±0.02 mm in the DIMS and SV groups, respectively. Myopia progressed 52% more slowly for children in the DIMS group compared with those in the SV group (mean difference -0.44±0.09 D, 95% CI -0.73 to -0.37, p<0.0001). Likewise, children in the DIMS group had less axial elongation by 62% than those in the SV group (mean difference 0.34±0.04 mm, 95% CI 0.22 to 0.37, p<0.0001). 21.5% children who wore DIMS lenses had no myopia progression over 2 years, but only 7.4% for those who wore SV lenses.
Daily wear of the DIMS lens significantly retarded myopia progression and axial elongation in myopic children. Our results demonstrated simultaneous clear vision with constant myopic defocus can slow myopia progression.
NCT02206217.
The dynamics of phytoplankton biomass in the vertically mixed south-eastern part of the Bisan Strait, in the Seto Inland Sea of Japan, may be considered to be strongly dependent not only on nutrients ...but also on light status. This was investigated by examining variations in chlorophyll-a (Chl-a), nutrients, and Secchi-disc depth through high-frequency sampling (a mean of once every 1.7 days) at the same station from April to October 2019. Precipitation during the Japanese rainy season (East Asian monsoon rains) was associated with a decrease in salinity from 32 to 31 in late July. The highest concentration of dissolved inorganic nitrogen (DIN), the most deficient nutrient, also was recorded in late July in association with seasonal precipitation. However, the measured Chl-a peak (max. 4 μg l−1) in early August was not as high as expected, possibly due to low water clarity. A relatively small but substantial peak of DIN (max. 4 μM) was recorded in mid-August, which coincided with the passing of a typhoon. The small peak of DIN coupled with higher water clarity thereafter was followed by a phytoplankton bloom from mid-August to early September, at which the highest Chl-a (7 μg l−1) occurred. It is suggested that increased light penetration enhanced the efficiency of nutrient assimilation and thereby triggered the late-summer phytoplankton bloom. In contrast to the adjacent stratified areas, light rather than nutrient status appears to be the key determinant for the onset of phytoplankton blooms in the Bisan Strait.
To compare visual function of myopic children who had worn either defocus incorporated multiple segment (DIMS) spectacle lenses or single vision (SV) spectacle lenses over two years.
We included 160 ...Chinese myopic (-1 diopter D to -5 D) children aged 8 to 13 years in a randomized clinical trial; they wore either DIMS lenses (DIMS;
= 79) or regular SV spectacles lenses (
= 81) full time for 2 years. Visual function, including high-contrast visual acuity (VA) and low-contrast VA at distance and near, binocular functions, and accommodation, before, during, and after 2 years of spectacle wear were assessed when both groups wore SV corrections. Changes of visual function between the two groups and within groups were compared.
There were no statistically significant differences in the 2-year visual function changes between DIMS and SV groups (repeated measures analysis of variance with group as factor;
> 0.05). Statistically significant improvement in the best-corrected distance high-contrast VA (
< 0.001) and stereoacuity score (
< 0.001) were found after DIMS lens wear over 2 years. Similar findings were observed after SV spectacle lens wear. For both the DIMS and SV groups, there were statistically significant decreases in accommodative lag, monocular and binocular amplitude of accommodation after two years (
< 0.01), but not in the changes in distance low-contrast VA, near high-contrast VA, near low-contrast VA, or phoria.
Although changes in some visual function were shown during 2 years of DIMS lens wear, similar changes were found with SV lens wear. Wear of DIMS spectacle lenses for 2 years does not adversely affect major visual function when children return to SV corrections.
DIMS spectacle lenses did not cause any adverse effects on visual function.
This paper proposes a MAC protocol for efficient broadcasting in wireless ad hoc networks. Pure flooding leads to serious redundant broadcasts, packet contention and packet collisions, known as the ...broadcast storm problem. This paper focuses on how to reduce the redundant broadcasts. Several protocols to achieve efficient broadcasting have been proposed. However a trade-off exists between the reachability and the broadcasting ratio, which is the ratio of the number of the broadcasting nodes to the number of received nodes. This paper proposes a new MAC protocol for on-demand broadcasting, which is referred to as dialogue-based protocol in order to resolve the trade-off. The dialogue-based protocol employs additional massages which are called as request packets and reply signals. They are exchanged in an on-demand manner, in order that relay candidate nodes recognize its neighbor nodes status whether they have already received the broadcast packets. Finally, by computer simulations, this paper presents that the dialogue-based scheme combines high reachability with low broadcasting ratio by using the low additional massages.
A field experiment of TV White Space (TVWS) communications was conducted using developed systems following IEEE 802.22 and IEEE 802.11af standards and succeeded to have the world first throughput, ...distance, and application testing. The IEEE 802.22 system achieved throughput of 4.5 Mbps for uplink and 5.2 Mbps for downlink over 12.7 km. Also, feasibility of applications such as web browsing, video streaming and video talk was confirmed in multi-hop network where the IEEE 802.22 system was a backbone link and IEEE 802.11af was access area expansion. Furthermore, aggregating bandwidth of two discontinuous TV channels, throughput of 15.5 Mbps for downlink and 9.0 Mbps for uplink was achieved over 6.3 km.
In this paper, we present a recently developed physical layer implementation of IEEE 802.22 prototype. The prototype includes the following components: a channel (CH) unit, a Medium Access Control ...Layer (MAC) Control unit, a Global Positioning System (GPS) unit and a Radio Frequency (RF) control unit. The prototype is developed in a flexible and scalable platform to enable future enhancement for higher data rate application. In order to achieve higher data rate, the prototype is designed to accommodate multiple channel units for multiple channel access capability. A channel unit consists of a MAC Layer unit, a Physical Layer (PHY) unit and a Transceiver (TRX) unit. In this paper, we will concentrate our discussion on the physical layer implementation of IEEE 802.22 prototype and show the Bit Error Rate (BER) performances of the implemented physical layer of IEEE 802.22 prototype.
In order to investigate the influence of procaine, which is closely related to cocaine on the chick embryo, thus to elucidate the action of procaine at the embryonal stage, the author carried out the ...following experiments. First of all, attempt was made to learn the toxicity of procaine from the influence of procaine on the hatching of the fertilized hens' eggs, and further, the influence on the development of chick embryo was observed. Furthermore, the influence of procaine on the allantoic fluid, egg yolk, egg white and amniotic fluid was investigated, and quantitative determination of procaine and its decomposition products contained in these parts of egg was conducted in order to trace the diffusion and distribution within the living body of procaine injected into the egg white. The principal results thus obtained are as follows. With the addition of procaine exceeding 10 mg, perfect hatching of the chick embryo was hardly attained. Procaine injected into the egg white may be excreted through the egg yolk first and then the chick embryo, into the allantoic fluid (amniotic fluid) . In the case with theinjection of 1 mg of procaine, the determined value of procaine and its decomposition products contained in the chick embryo almost did not fluctuate during the entire incubation period. However, in the case with injection of 5 mg of procaine, the determined value was found increased as the incubation progressed. In this cases, the determinedd value of allantoic fluid was found gradually increased to reach the maximum on the 15 thh day of incubation. Contrary to this, the values of egg yolk and egg white were found decreased as the incubation progressed.
When the great disaster strikes, it is most important for victims to receive and transmit appropriate information in order to evacuate immediately and to request for assistance and rescue. The Great ...East Japan Earthquake teaches us the importance of information communication technology (ICT) using wireless communication technology, e.g., television (TV), radio, the community wireless system for disaster, and mobile phone. However, after the disaster occurrence, particularly, mobile phones were left unusable for a long time due to network congestion, physical damage to base stations, and out-of-fuel of standby power systems. To combat these problems, the ICT services require more robustness, availability, flexibility, and redundancy. In this paper, we discuss the competence of IEEE standard 802.22-based wireless regional area network (WRAN) using television white space (TVWS) which can provide wide service area and utilize geographically or temporally unoccupied resource of TV frequency bands, although the frequency bands are allocated by regulatory domain. Furthermore, we introduce and evaluate a developed prototype of the WRAN equipment. The prototype provides point-to-multipoint service and throughput up to 12.2 Mbps in downstream (DS) and 9.5 Mbps in upstream (US).
The author investigated the influences of Cytochrome-C on the general development and various metabolisms of the chick embryo by giving Cytochrome-C to developing hen's eggs. The present work is ...divided into two parts. In the Exp. (I), the drug was administered prior to the incubation, and in the Exp. (II), the drug was administered on the 5 th day of incubation. The followings are the results thus obtained. (1) In both of the Exp. (I) and Exp. (II), no systematic influences on the general development of the chick embryo were found exercised by the administration of Cytochrome-C. (2) The Pyruvic acid contents in the allantoic fluid in the latter half of the incubation in the case treated with 300γ and on the 15 th day of incubation in the case treated with 600γ of Cytochrome-C in the Exp. (I) were evidently larger compared with those of the control eggs. (3) The N-contents in the allantoic fluid in the cases treated with 300γ and 600γ of Cytochrome-C in the Exp. (I) were larger compared with those of the control eggs on the 12 th and 15 th day of incubation. In the Exp. (II), in the first half of the incubation period of the cases treated with 300γ of Cytochrome-C and on the 12 th and 18 th day of incubation in the cases treated with 600γ of Cytochrome-C, the N-contents in the allantoic fluid were found larger compared with the control. (4) The Vitamin B1 contents in the allantoic fluid were investigated only in the Exp. (II) . They were found larger compared with the control on the 15 th day of incubation in both of the cases treated with 300γ and 600γ of Cytochrome-C.
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