The explosive eruption of the Hunga-Tonga volcano in the southwest Pacific at 0415UT on 15 January 2022 triggered gigantic atmospheric disturbances with surface air pressure waves propagating around ...the globe in Lamb mode. In space, concentric traveling ionosphere disturbances (CTIDs) are also observed as a manifestation of air pressure waves in New Zealand ∼0500UT and Australia ∼0630UT. As soon as the air pressure waves reached central Australia ∼0800UT, conjugate CTIDs appeared almost simultaneously in the northern hemispheres through interhemispheric coupling, much earlier than the arrival of the surface air pressure waves to Japan after 1100UT. Combining observations over Australia and Japan between 0800 and 1000UT, both direct and conjugate CTIDs show similar horizontal phase velocities of 320–390 m/s, matching with the dispersion relation of Lamb mode. The arrival of atmospheric Lamb wave to Japan later created in situ CTIDs showing the same Lamb mode characteristics as the earlier conjugate CTIDs.
The FORMOSAT‐7/COSMIC‐2 (F7/C2) satellite mission was launched on 25 June 2019 with six low‐Earth‐orbit satellites and can provide thousands of daily radio occultation (RO) soundings in the ...low‐latitude and midlatitude regions. This study shows the preliminary results of space weather data products based on F7/C2 RO sounding: global ionospheric specification (GIS) electron density and Ne‐aided Abel and Abel electron density profiles. GIS is the ionospheric data assimilation product based on the Gauss‐Markov Kalman filter, assimilating the ground‐based Global Positioning System and space‐based F7/C2 RO slant total electron content, providing continuous global three‐dimensional electron density distribution. The Ne‐aided Abel inversion implements four‐dimensional climatological electron density constructed from previous RO observations, which has the advantage of providing altitudinal information on the horizontal gradient to reduce the retrieval error due to the spherical symmetry assumption of the Abel inversion. The comparisons show that climatological structures are consistent with each other above 300 km altitude. Both the Abel electron density profiles and GIS detect electron density variations during a minor geomagnetic storm that occurred within the study period. Moreover, GIS is further capable of reconstructing the variation of equatorial ionization anomaly crests. Detailed validations of all the three products are carried out using manually scaled digisonde NmF2 (hmF2), yielding correlation coefficients of 0.885 (0.885) for both Abel inversions and 0.903 (0.862) for GIS. The results show that both GIS and Ne‐aided Abel are reliable products in studying ionosphere climatology, with the additional advantage of GIS for space weather research and day‐to‐day variations.
Plain Language Summary
This study presents two ionosphere products from the innovative satellite constellation mission launched recently. Global ionospheric specification is an ionospheric data product that assimilates ground‐based Global Positioning System and FORMOSAT‐7/COSMIC‐2 radio occultation observation of total electron content, to generate hourly global three‐dimensional electron density for monitoring space weather condition. Ne‐aided Abel electron density profile is an improved retrieval product of FORMOSAT‐7/COSMIC‐2 radio occultation observations by imposing asymmetry information of ionosphere to mitigate the error introduced by the assumption of spherical symmetry in the Abel inversion. The comparisons and validations confirm that these two data products are reliable for the study of ionosphere climatology and weather. They are operationally produced and released at Taiwan Analysis Center for COSMIC.
Key Points
All the three F7/C2 products capture similar climatological structure of ionosphere in longitudes (Wave 4) and latitudes (EIA crests)
Abel electron density profiles detect responses to geomagnetic storm, but GIS performs better in reconstructing the EIA crests variations
Digisonde validations demonstrate that the GIS NmF2 has excellent performance when there are RO observations available for assimilation
Two remarkable typhoon‐induced traveling ionospheric disturbances (TIDs) with concentric and northwest‐southeast (NW‐SE) alignments, respectively, associated with concentric gravity waves (CGWs) and ...ionosphere instabilities possibly seeded by CGWs, were observed in total electron content (TEC) derived from ground‐based Global Navigation Satellite System networks in Taiwan and Japan when the Category 5 Super Typhoon Nepartak approached Taiwan on 7 July 2016. The concentric TIDs (CTIDs) first appear with horizontal phase velocities of ~161–200 m/s, horizontal wavelengths of ~160–270 km, and periods of ~15–22 min during 08:00–11:20 UT. Following the CTIDs, the NW‐SE aligned nighttime medium‐scale TIDs (MSTIDs) are formed on the west edge of the CTIDs over the Taiwan Strait during 11:30–14:00 UT. It is suggested that the MSTIDs are produced by the electrodynamical coupling of Perkins instability and CGW‐induced polarization electric fields. This study proposes connections of typhoon‐induced CTIDs and subsequently occurring MSTIDs in the low‐latitude ionosphere.
Key Points
Concentric and medium‐scale traveling ionosphere disturbances excited by Super Typhoon Nepartak (2016) are observed in GNSS TEC
Nighttime MSTIDs with NW‐SE alignment of wavefronts occurred on the west edge of CTIDs
Electrodynamical coupling of Perkins instability and CGWs‐induced electric fields could explain the typhoon‐induced nighttime MSTID
An earthquake of magnitude 9.0 occurred near the east coast of Honshu (Tohoku area), Japan, producing overwhelming Earth surface motions and inducing devastating tsunamis, which then traveled into ...the ionosphere and significantly disturbed the electron density within it (hereafter referred to as seismotraveling ionospheric disturbances (STIDs)). The total electron content (TEC) derived from nationwide GPS receiving networks in Japan and Taiwan is employed to monitor STIDs triggered by seismic and tsunami waves of the Tohoku earthquake. The STIDs first appear as a disk‐shaped TEC increase about 7 min after the earthquake occurrence centered at about 200 km east of the epicenter, near the west edge of the Japan Trench. Fast propagating disturbances related to Rayleigh waves quickly travel away from the epicenter along the main island of Japan with a speed of 2.3–3.3 km/s, accompanied by sequences of concentric circular TEC wavefronts and followed by circular ripples (close to a tsunami speed of about 720–800 km/h) that travel away from the STID center. These are the most remarkable STIDs ever observed where signatures of Rayleigh waves, tsunami waves, etc., simultaneously appear in the ionosphere.
Key Points
Ionospheric disturbances generated by earthquake and tsunami
Greatest disturbances ever seen containing signatures of following waves
Rayleigh, acoustic, and tsunami‐generated waves
Seismic waves can be detected in the Earth's atmosphere and ionosphere; however, their impacts on ionospheric electron density (Ne) structures near the altitude of peak Ne (hmF2) have not yet been ...fully determined due to the lack of sufficient observations sampled in the vertical direction. Here we apply a ground‐based Global Positioning System (GPS) receiving network in Asia as well as the space‐based GPS occultation experiment on board the FORMOSAT‐3/COSMIC (F3/C) satellite to vertically scan the ionospheric Ne structures, which were perturbed by the magnitude Mw7.8 Nepal earthquake that occurred on 25 April 2015. The F3/C altitudinal Ne profiles show that the Nepal earthquake‐induced air perturbations penetrate into the ionosphere at supersonic speeds of approximately 800 m/s and change the Ne structure by 10% near hmF2. The vertical scale of the Ne perturbation is 150 km, while the hmF2 is uplifted by more than 30 km within 1 min. Those results reveal that the earthquake‐induced ground displacement should be considered as a significant force that perturbs the vertical Ne structure of the ionosphere.
Key Points
Coseismic ionospheric disturbance observed by FORMOSAT‐3/COSMIC
Near‐supersonic uplifting of the ionospheric F2 peak caused by the Nepal earthquake
Vertical scale of the coseismic disturbance is near 150 km in the F2 region
Tsunami ionospheric disturbances (TIDs) of the 26 December 2004 Mw 9.3 Sumatra earthquake are detected by the total electron content (TEC) of ground‐based receivers of the global positioning system ...(GPS) in the Indian Ocean area. It is found that the tsunami waves triggered atmospheric disturbances near the sea surface, which then traveled upward with an average velocity of about 730 m/s (2700 km/hr) into the ionosphere and significantly disturbed the electron density within it. Results further show that the TIDs, which have maximum height of about 8.6–17.2 km, periods of 10–20 min, and horizontal wavelengths of 120–240 km, travel away from the epicenter with an average horizontal speed of about 700 km/hr (190 m/s) in the ionosphere.
FORMOSAT-3/COSMIC (F3/C) constellation of six micro-satellites was launched into the circular low-earth orbit at 800 km altitude with a 72-degree inclination angle on 15 April 2006, uniformly ...monitoring the ionosphere by the GPS (Global Positioning System) Radio Occultation (RO). Each F3/C satellite is equipped with a TIP (Tiny Ionospheric Photometer) observing 135.6 nm emissions and a TBB (Tri-Band Beacon) for conducting ionospheric tomography. More than 2000 RO profiles per day for the first time allows us globally studying three-dimensional ionospheric electron density structures and formation mechanisms of the equatorial ionization anomaly, middle-latitude trough, Weddell/Okhotsk Sea anomaly, etc. In addition, several new findings, such as plasma caves, plasma depletion bays, etc., have been reported. F3/C electron density profiles together with ground-based GPS total electron contents can be used to monitor, nowcast, and forecast ionospheric space weather. The S4 index of GPS signal scintillations recorded by F3/C is useful for ionospheric irregularities monitoring as well as for positioning, navigation, and communication applications. F3/C was officially decommissioned on 1 May 2020 and replaced by FORMOSAT-7/COSMIC-2 (F7/C2). F7/C2 constellation of six small satellites was launched into the circular low-Earth orbit at 550 km altitude with a 24-degree inclination angle on 25 June 2019. F7/C2 carries an advanced TGRS (Tri Gnss (global navigation satellite system) Radio occultation System) instrument, which tracks more than 4000 RO profiles per day. Each F7/C2 satellite also has a RFB (Radio Reference Beacon) on board for ionospheric tomography and an IVM (Ion Velocity Meter) for measuring ion temperature, velocity, and density. F7/C2 TGRS, IVM, and RFB shall continue to expand the F3/C success in the ionospheric space weather forecasting.
Key Points
FORMOSAT-3/COSMIC and FORMOSAT-7/COSMIC-2 uniformly observe 3D electron density.
FORMOSAT-3 and FORMOSAT-7 enable ionospheric weather forecasting.
FORMOSAT-7/COSMIC-2 TGRS and IVM have a better understanding of the electrodynamics of ionospheric plasma.
Aims and objectives
The purpose of this study was to investigate the adverse effects of non‐intubated suctioning.
Background
Airway hygiene aims to maintain a patent airway to ensure adequate ...ventilation. Nasopharyngeal, oropharyngeal or nasotracheal suctioning may be used in patients who require airway suctioning but do not have an artificial airway. However, no studies till date provide insight into the adverse effects of non‐intubated airway suctioning.
Design
A clinical data‐based retrospective design.
Method
Using institutional and clinical databases of three university hospitals in 2008–2016, we conducted a study with a propensity score matching method of 3,326 hospitalised patients who had undergone suction therapy with or without a tracheotomy. Conditional logistic regression analyses were performed to investigate the link between suctioning and the probabilities of adverse effects. STROBE checklist was used to report the current study.
Results
Patients who required nasopharyngeal, oropharyngeal or nasotracheal suctioning had a higher risk of gastrointestinal ulcers than tracheotomised patients (adjusted OR 1.99; 95% CI, 1.24–3.20). Patients who received non‐intubated suction had a higher risk of developing pneumonia (adjusted OR 1.59; 95% CI, 1.26–2.00), and the risk of aspiration pneumonia was three times higher than tracheotomised patients (adjusted OR 3.04; 95% CI, 1.40–6.60).
Conclusions
Non‐intubated patients who require suctioning for airway clearing are more susceptible to gastrointestinal ulcers, pneumonia and aspiration pneumonia. The findings would facilitate in alerting healthcare professionals to this group of patients. However, more clinical research is needed to elucidate the mechanisms of adverse effects in non‐intubated patients who require suctioning.
Relevance to Clinical Practice
The adverse effects of suctioning can easily be overlooked in debilitated patients with no intubation. Professionals must be aware of the discomfort and risks that patients may experience.
Neck dissection is an integral component of the treatment of head and neck cancers. The present meta-analysis aimed to compare the use of endoscope-assisted neck dissection (END) with conventional ...neck dissection (CND) in the existing English literature.
A search of PubMed (MEDLINE), Embase, and the Cochrane Library for articles reporting the results of the two techniques of neck dissection was completed independently by two individuals. The authors analyzed the data from each study using a random-effects model.
The pooled analysis demonstrated comparable lymph node yield, intraoperative blood loss, incidence of locoregional recurrence, and incidence of complications between the two groups. A significantly longer operative time but a shorter length of hospital stay was observed in the END group compared with the other group.
Compared with conventional techniques, END offers similar oncologic outcomes and complication rates; however, it requires a longer operative time. Future studies with long-term follow-up and assessment of patient satisfaction are needed to confirm the clinical use of END.
Aims
To investigate the relationships among social support, health literacy, and self‐management, and the factors influencing self‐management of chronic kidney disease (CKD).
Design
Cross‐sectional ...study.
Methods
A random sample of 410 patients was recruited from nephrology clinics. Data were collected using structured questionnaires and chart reviews from January 2013 to February 2014. Hierarchical regression analysis was used to determine the predictive factors of self‐management behaviors and ∆R2 to determine each variable's explanatory power.
Findings
Health literacy and social support were positively correlated with self‐management behaviors. Furthermore, social support, health literacy, and marital status were significant predictors of self‐management behaviors. Social support had a relatively greater explanatory power for self‐management behaviors than did health literacy. Particularly, healthcare provider support had the greatest influence on patients’ self‐management behaviors.
Conclusions
Health literacy and social support play independent positive roles in self‐management behaviors of patients with CKD, with social support having a particularly dominant role. Further research using a systems approach to improving self‐management behaviors is necessary to clarify the role of social support.
Clinical Relevance
Health literacy and social support are independently and positively related to self‐management. Social support, which is a system‐level factor, is a relatively stronger and crucial predictor than is health literacy. Nurses have to refine self‐management programs to focus on families and adopt a systems approach to help CKD patients improve their self‐management behaviors.
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