scholarly journals The occurrence rate of acute-onset postoperative endophthalmitis after cataract surgery in Chinese small- and medium-scale departments of ophthalmology

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Yanan Zhu ◽  
Xinyi Chen ◽  
Peiqing Chen ◽  
Jianjun Wu ◽  
Huixia Hua ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Acute Onset ◽  
Occurrence Rate ◽  
Postoperative Endophthalmitis ◽  
Medium Scale

Acute-onset postoperative endophthalmitis after cataract surgery and transzonular intravitreal triamcinolone–moxifloxacin

2018 ◽  
Vol 44 (12) ◽  
pp. 1436-1440 ◽  
Author(s):  
Kamal Kishore ◽  
Jeffrey A. Brown ◽  
Jennifer M. Satar ◽  
John M. Hahn ◽  
William I. Bond
Keyword(s):  
Cataract Surgery ◽  
Acute Onset ◽  
Postoperative Endophthalmitis ◽  
Intravitreal Triamcinolone

scholarly journals Investigation of Low Latitude Spread-F Triggered by Nighttime Medium-Scale Traveling Ionospheric Disturbance

2021 ◽  
Vol 13 (5) ◽  
pp. 945
Author(s):  
Zhongxin Deng ◽  
Rui Wang ◽  
Yi Liu ◽  
Tong Xu ◽  
Zhuangkai Wang ◽  
...  
Keyword(s):  
Ionospheric Disturbance ◽  
Phase Speed ◽  
Morphological Processing ◽  
Wave Number ◽  
Occurrence Rate ◽  
Electron Content ◽  
Low Latitude ◽  
Total Electron ◽  
Medium Scale ◽  
Spread F

In the current study, we investigated the mechanism of medium-scale traveling ionospheric disturbance (MSTID) triggering spread-F in the low latitude ionosphere using ionosonde observation and Global Navigation Satellite System-Total Electron Content (GNSS-TEC) measurement. We use a series of morphological processing techniques applied to ionograms to retrieve the O-wave traces automatically. The maximum entropy method (MEM) was also utilized to obtain the propagation parameters of MSTID. Although it is widely acknowledged that MSTID is normally accompanied by polarization electric fields which can trigger Rayleigh–Taylor (RT) instability and consequently excite spread-F, our statistical analysis of 13 months of MSTID and spread-F occurrence showed that there is an inverse seasonal occurrence rate between MSTID and spread-F. Thus, we assert that only MSTID with certain properties can trigger spread-F occurrence. We also note that the MSTID at night has a high possibility to trigger spread-F. We assume that this tendency is consistent with the fact that the polarization electric field caused by MSTID is generally the main source of post-midnight F-layer instability. Moreover, after thorough investigation over the azimuth, phase speed, main frequency, and wave number over the South America region, we found that the spread-F has a tendency to be triggered by nighttime MSTID, which is generally characterized by larger ΔTEC amplitudes.

scholarly journals Climatology of Medium-Scale Traveling Ionospheric Disturbances (MSTIDs) Observed with GPS Networks in the North African Region

2020 ◽  
Author(s):  
Temitope Seun Oluwadare ◽  
Norbert Jakowski ◽  
Cesar E. Valladares ◽  
Andrew Oke-Ovie Akala ◽  
Oladipo E. Abe ◽  
...  
Keyword(s):  
Gravity Waves ◽  
Occurrence Rate ◽  
Ionospheric Disturbances ◽  
North African ◽  
African Region ◽  
Atmospheric Gravity Waves ◽  
Medium Scale ◽  
Traveling Ionospheric Disturbances ◽  
The North ◽  
Atmospheric Gravity

Abstract We present for the first time the climatology of medium-scale traveling ionospheric disturbances (MSTIDs) by using Global Positioning System (GPS) receiver networks on geomagnetically quiet days (Kp ≤ 3) over the North African region during 2008-2016. The MSTIDs appear frequently as oscillating waves or wave-like structures in electron density induced by the passage of Atmospheric Gravity Waves (AGW) propagating through the neutral atmosphere and consequently, causing fluctuation in the ionospheric Total Electron Content (TEC). The TEC perturbations (dTEC) data are derived from dual frequency GPS-measurements. We have statistically analyzed the MSTIDs characteristics, occurrence rate, seasonal behavior as well as the interannual dependence. The results show a local and seasonal dependence of nighttime and daytime MSTIDs. The propagation direction is predominantly towards the South (equatorward), MSTIDs event period is (12 ≤ period ≤ 53 mins), and dominant amplitude (0.08 ≤ amp ≤ ~1.5 TECU), with a propagation velocity higher at daytime than nighttime. The amplitudes of the MSTIDs increase with solar activity. The local MSTIDs Spatio-temporal heat reveals variability in disturbance occurrence time, but seems to be dominant within the hours of (Northwest: 1200–1600 LT) and (Northeast: 1000–1400 LT) in December solstice during daytime, and around (NW: 2100–0200 LT) and (NE: 1900–0200 LT) in June solstice, but get extended to March equinox during solar maximum (2014) during the nighttime. The time series of MSTIDs regional distribution map is also generated. Atmospheric gravity waves (AGW) seems to be responsible for the daytime MSTIDs occurrence.

ESCRS study of prophylaxis of postoperative endophthalmitis after cataract surgery

2006 ◽  
Vol 32 (3) ◽  
pp. 396-406 ◽  
Author(s):  
David V. Seal ◽  
Peter Barry ◽  
George Gettinby ◽  
Fiona Lees ◽  
Magnus Peterson ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Postoperative Endophthalmitis

Acute-onset Endophthalmitis After Cataract Surgery (2000–2004): Incidence, Clinical Settings, and Visual Acuity Outcomes After Treatment

2005 ◽  
Vol 139 (6) ◽  
pp. 983-987 ◽  
Author(s):  
John J. Miller ◽  
Ingrid U. Scott ◽  
Harry W. Flynn ◽  
William E. Smiddy ◽  
Jean Newton ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Acute Onset ◽  
Clinical Settings
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