scholarly journals Comparing Sudden Stratospheric Warming Definitions in Reanalysis Data*

2015 ◽  
Vol 28 (17) ◽  
pp. 6823-6840 ◽  
Author(s):  
Froila M. Palmeiro ◽  
David Barriopedro ◽  
Ricardo García-Herrera ◽  
Natalia Calvo
Keyword(s):  
Seasonal Cycle ◽  
Winter Season ◽  
Reanalysis Data ◽  
Sudden Stratospheric Warming ◽  
Pronounced Increase ◽  
Future Studies ◽  
Common Peak ◽  
Before And After ◽  
The Mean ◽  
Large Case

Abstract Sudden stratospheric warmings (SSWs) are characterized by a pronounced increase of the stratospheric polar temperature during the winter season. Different definitions have been used in the literature to diagnose the occurrence of SSWs, yielding discrepancies in the detected events. The aim of this paper is to compare the SSW climatologies obtained by different methods using reanalysis data. The occurrences of Northern Hemisphere SSWs during the extended-winter season and the 1958–2014 period have been identified for a suite of eight representative definitions and three different reanalyses. Overall, and despite the differences in the number and exact dates of occurrence of SSWs, the main climatological signatures of SSWs are not sensitive to the considered reanalysis. The mean frequency of SSWs is 6.7 events decade−1, but it ranges from 4 to 10 events, depending on the method. The seasonal cycle of events is statistically indistinguishable across definitions, with a common peak in January. However, the multidecadal variability is method dependent, with only two definitions displaying minimum frequencies in the 1990s. An analysis of the mean signatures of SSWs in the stratosphere revealed negligible differences among methods compared to the large case-to-case variability within a given definition. The stronger and more coherent tropospheric signals before and after SSWs are associated with major events, which are detected by most methods. The tropospheric signals of minor SSWs are less robust, representing the largest source of discrepancy across definitions. Therefore, to obtain robust results, future studies on stratosphere–troposphere coupling should aim to minimize the detection of minor warmings.

scholarly journals Composite analysis of a major sudden stratospheric warming

2015 ◽  
Vol 33 (6) ◽  
pp. 783-788 ◽  
Author(s):  
K. Hocke ◽  
M. Lainer ◽  
A. Schanz
Keyword(s):  
Geopotential Height ◽  
Reanalysis Data ◽  
Composite Analysis ◽  
Stratospheric Warming ◽  
Analysis Method ◽  
Sudden Stratospheric Warming ◽  
Reliable Prediction ◽  
The Mean ◽  
The Individual ◽  
Ozone Column

Abstract. We present the characteristics of a major sudden stratospheric warming (SSW) by using the composite analysis method and ERA Interim reanalysis data from 1979 to 2014. The anomalies of the parameters total ozone column density (TOC), temperature (T), potential vorticity (PV), eastward wind (u), northward wind (v), vertical wind (w), and geopotential height (z) are derived with respect to the ERA Interim climatology (mean seasonal behaviour 1979 to 2014). The composites are calculated by using the time series of the anomalies and the central dates of 20 major SSWs. Increases of up to 90 Dobson units are found for polar TOC after the SSW. Polar TOC remains enhanced until the summer after the major SSW. Precursors of the SSW are a negative TOC anomaly 3 months before the SSW and enhanced temperature at 10 hPa at mid-latitudes about 1 month before the SSW. Eastward wind at 1 hPa is decreased at mid-latitudes about 1 month before the SSW. The 1 hPa geopotential height level is increased by about 500 m during the month before the SSW. These features are significant at the 2σ level for the mean behaviour of the ensemble of the major SSWs. However, knowledge of these precursors may not lead to a reliable prediction of an individual SSW since the variability of the individual SSWs and the polar winter stratosphere is large.

scholarly journals Analysis of the Arctic polar vortex dynamics during the sudden stratospheric warming in January 2009

2021 ◽  
Vol 67 (2) ◽  
pp. 134-146
Author(s):  
V. V. Zuev ◽  
E. S. Savelieva ◽  
A. V. Pavlinsky
Keyword(s):  
Wind Speed ◽  
Polar Vortex ◽  
Reanalysis Data ◽  
Wave Activity ◽  
The Arctic ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Mean Wind Speed ◽  
The Mean ◽  
Middle Stratosphere

The Arctic polar vortex is often affected by wave activity during its life cycle. The planetary Rossby waves propagating from the troposphere to the stratosphere occasionally lead to the displacement or splitting of the polar vortex, accompanied by sudden stratospheric warming (SSW). In January 2009, one of the largest SSWs was observed in the Arctic. In this work, the dynamics of the polar vortex during the 2009 SSW is considered using a new method that allows one to estimate the vortex area, the wind speed at the vortex edge, the mean temperature and ozone mass mixing ratio inside the vortex, based on the fact that the Arctic vortex edge at the 50 and 10 hPa pressure levels is determined by the geopotential values, respectively, 19.5. 104 and 29.5. 104 m2 /s2 , using the ERA5 reanalysis data. The application of this method is justified for the Arctic polar vortex, which is characterized by significant variability, especially during the period of its splitting. The splitting of the polar vortex in 2009 was observed on January 24 and 28, respectively, in the middle and lower stratosphere. About a week after the splitting, the vortices became closer in characteristics to small cyclones, which completely collapsed within 1–3 weeks. The influence of planetary wave activity on the polar vortex does not always lead to its breakdown. Short-term splitting of the polar vortex is sometimes observed for several days after which the polar vortex strengthens again and PSCs form inside the vortex. Such a recovery of the polar vortex is most likely to occur in the winter. Based on the analysis of the dynamics of the Arctic polar vortex for 1979–2020 and using the example of the 2009 SSW, we showed that when the vortex area decreases to less than 10 million km2 and the mean wind speed at the vortex edge decreases below 30 and 45 m/s, respectively, in the lower and middle stratosphere, the polar vortex becomes a small cyclone (with significantly higher temperatures within it), which usually collapses within 3 weeks.

scholarly journals Type Classification of Sudden Stratospheric Warming Based on Pre- and Postwarming Periods

2019 ◽  
Vol 32 (8) ◽  
pp. 2349-2367 ◽  
Author(s):  
Hyesun Choi ◽  
Baek-Min Kim ◽  
Wookap Choi
Keyword(s):  
Geopotential Height ◽  
Wave Amplitude ◽  
Reanalysis Data ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Evolution Characteristics ◽  
Zonal Wavenumber ◽  
Before And After ◽  
Type Classification

Abstract In existing literature, sudden stratospheric warming (SSW) events have been typically defined as displacement or split types. Detailed reexamination of SSW evolution has revealed that an SSW event often alters its type before and after the central day of the warming event. On the basis of this observation, we objectively define three types of SSW using wave amplitude: displacement–displacement (DD) type, displacement–split (DS) type, and split–split (SS) type. The geopotential height (GPH) amplitude of zonal wavenumbers 1 and 2 averaged over 55°–65°N at 10 hPa was used as a criterion for the classification. If the amplitude of zonal wavenumber 1 is larger (smaller) than that of wavenumber 2 before and after the central day of SSW, the event is regarded as a DD (SS) type. If the amplitude of zonal wavenumber 1 is larger than that of wavenumber 2 before the central day but is smaller after that day, the event is regarded as a DS type. The above classification algorithm has been applied to both reanalysis data and model results. We observe that conventional split-type SSW events identified by previous studies can be categorized as either DS- or SS-type events, each type of which exhibits different evolution characteristics. In particular, they are distinctively different during the prewarming period. In the SS type, the characteristics of the conventional split type are more obvious, and the features that differ from those of the DD type are the most robust. The model results generally resemble the reanalysis data, particularly in the DD cases.

scholarly journals Effect of Intestinal Levodopa-Carbidopa Infusion on Pharyngeal Dysphagia: Results from a Retrospective Pilot Study in Patients with Parkinson’s Disease

2020 ◽  
Vol 2020 ◽  
pp. 1-6 ◽  
Author(s):  
Bendix Labeit ◽  
Inga Claus ◽  
Paul Muhle ◽  
Sonja Suntrup-Krueger ◽  
Rainer Dziewas ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Common Symptom ◽  
Yahr Stage ◽  
Future Studies ◽  
Pharyngeal Dysphagia ◽  
Before And After ◽  
The Mean ◽  
Larger Sample

Background. Pharyngeal dysphagia is a common symptom of Parkinson’s disease (PD) leading to severe complications. PD-related pharyngeal dysphagia (PDrPD) may significantly improve in up to half of patients following acute oral levodopa challenge. Objective. The aim of this study was to investigate the effects of levodopa-carbidopa intestinal gel (LCIG) on PDrPD. Methods. Forty-five PD patients under LCIG treatment were available for retrospective analysis. In all patients with PDrPD who underwent flexible endoscopic evaluation of swallowing (FEES) in the clinical “on-state” both before and after implementation of LCIG treatment, FEES videos were systematically reassessed. PDrPD was characterized using a PD-specific FEES score evaluating premature bolus spillage, penetration/aspiration, and pharyngeal residue. Further, the duration of white-out was assessed, as a parameter for pharyngeal bradykinesia. Results. Eleven patients with PDrPD (mean age 74.6 ± 4.4 years; mean Hoehn and Yahr stage 3.8 ± 0.6) received FEES both before and after the onset of LCIG treatment. The mean swallowing score improved from 14.9 ± 7.3 to 13.0 ± 6.9 after implementation of LCIG; however, this difference was not significant (p=0.312). Premature bolus spillage decreased significantly (p=0.002) from 5.4 ± 1.1 to 3.6 ± 1.0, and white-out duration decreased significantly (p=0.002) from 984 ± 228 ms to 699 ± 131 ms after implementation of LCIG. Conclusions. LCIG may affect PDrPD and reduce premature bolus spillage and pharyngeal bradykinesia. Future studies with larger sample sizes are required to follow-up on these pilot results and identify which factors predict a good response of PDrPD to LCIG treatment.

Perbedaan Pengetahuan Siswa Tentang Penyakit Hepatitis A Sebelum Dan Sesudah Penyuluhan Di MTsN 02 Bondowoso Tahun 2015

2017 ◽  
Vol 4 (2) ◽  
pp. 14
Author(s):  
Putri Megasari
Keyword(s):  
Hepatitis A ◽  
Hepatitis Virus ◽  
Sampling Technique ◽  
Mean Value ◽  
Test Design ◽  
The World ◽  
Before And After ◽  
Post Test ◽  
The Mean ◽  
Paired T Test

Hepatitis has become a health problem in the world. The hepatitis virus infected many people. According to the teacher of MTsN 02 Bondowoso more than 20 students have hepatitis A viral infection. The purpose of this research was to know the differences of students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study used pre-experimental (pre-post test design). This study used stratified random sampling technique, 127 students from 270 sample involved this research,and 143 students was excluded. We used questionnaires to collect data. The results showed that the mean value of the students 'knowledge about hepatitis A before counseling in MTsN 02 Bondowoso 2015 was 83.96 with the lowest value of 37.5 and the highest value was 100. The mean value of the students' knowledge about hepatitis A after counseling in MTsN 02 Bondowoso 2015 was 93.21 with the lowest value waf 62.5 and the highest value was 100. Paired t test showed that t (-9.07) > t table (1.98), the null hypothesis (H0) was rejected. There was a difference between students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study showed that routine counseling by healthcare provider was important to prevent hepatitis A infection.; Keywords: counseling, knowledge of students, hepatitis

Quality of Life for Children with Persistent Sinonasal Symptoms

2003 ◽  
Vol 128 (1) ◽  
pp. 17-26 ◽  
Author(s):  
David J. Kay ◽  
Richard M. Rosenfeld
Keyword(s):  
Quality Of Life ◽  
Clinical Care ◽  
Longitudinal Change ◽  
Good Test ◽  
Routine Clinical Care ◽  
Before And After ◽  
The Mean ◽  
The Individual ◽  
Sinonasal Symptoms

OBJECTIVE: The goal was to validate the SN-5 survey as a measure of longitudinal change in health-related quality of life (HRQoL) for children with persistent sinonasal symptoms. DESIGN AND SETTING: We conducted a before and after study of 85 children aged 2 to 12 years in a metropolitan pediatric otolaryngology practice. Caregivers completed the SN-5 survey at entry and at least 4 weeks later. The survey included 5 symptom-cluster items covering the domains of sinus infection, nasal obstruction, allergy symptoms, emotional distress, and activity limitations. RESULTS: Good test-retest reliability ( R = 0.70) was obtained for the overall SN-5 score and the individual survey items ( R ≥ 0.58). The mean baseline SN-5 score was 3.8 (SD, 1.0) of a maximum of 7.0, with higher scores indicating poorer HRQoL. All SN-5 items had adequate correlation ( R ≥ 0.36) with external constructs. The mean change in SN-5 score after routine clinical care was 0.88 (SD, 1.19) with an effect size of 0.74 indicating good responsiveness to longitudinal change. The change scores correlated appropriately with changes in related external constructs ( R ≥ 0.42). CONCLUSIONS: The SN-5 is a valid, reliable, and responsive measure of HRQoL for children with persistent sinonasal symptoms, suitable for use in outcomes studies and routine clinical care.

scholarly journals Evaluation of pharmacy-led weight management service to minimise the risk of cardiovascular disease

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Aliki Peletidi ◽  
Reem Kayyali
Keyword(s):  
Physical Activity ◽  
Weight Management ◽  
Activity Levels ◽  
Management Service ◽  
Initial Weight ◽  
Public Health Services ◽  
Clinical Role ◽  
Physical Activity Levels ◽  
Before And After ◽  
The Mean

Abstract Aims The primary aim of the programme was a minimum of a 5% weight reduction of the initial weight, while the secondary outcomes were a reduction in participants’ body mass index (BMI), waist circumference (WC), blood pressure (BP), AUDIT-C score and an increase in the Mediterranean diet (MD) score and an improvement in physical activity levels. Methods This 'before and after' study was a 10-week weight management (WM) programme and it was developed and delivered in community pharmacies in Patras chosen for convenience, thus consisting the first service of its type in Greece. The sample size was calculated (n = 96) based on the mean BMI for a Greek male and female individual, and the standard deviation (SD) of weight at baseline of 14 kg. Results Nearly every participant enrolled in the 20 participating pharmacies, 97.4% (n = 114/117), achieved the programme’s aim, losing at least 5% of their initial weight. The mean percentage of total weight loss of the 117 participants at the 10th week was 8.97% (SD 2.65), and the t-test showed statistically significant results (P-value < 0.001; 95% CI [8.48, 9.45]). A significant reduction in the waist-to-height ratio (WHtR) was observed in both male (P-value = 0.004) and female (P-value < 0.001) participants. The participants’ BP and AUDIT-C score and physical activity levels significantly improved (P-value < 0.001), as well as their MD score. Conclusion This study provides the first evidence that Greek pharmacists have the potential to play an important role within primary healthcare and that after training they are able to provide public health services for both the public’s benefit and their clinical role enhancement.

scholarly journals CT perfusion in peripheral arterial disease—hemodynamic differences before and after revascularisation

2021 ◽  
Author(s):  
Patrick Veit-Haibach ◽  
Martin W. Huellner ◽  
Martin Banyai ◽  
Sebastian Mafeld ◽  
Johannes Heverhagen ◽  
...  
Keyword(s):  
Peripheral Arterial Disease ◽  
Ct Perfusion ◽  
Arterial Disease ◽  
Lower Leg ◽  
Therapy Control ◽  
Non Invasive ◽  
Before And After ◽  
Invasive Method ◽  
The Mean ◽  
Peripheral Arterial

Abstract Objectives The purpose of this study was the assessment of volumetric CT perfusion (CTP) of the lower leg musculature in patients with symptomatic peripheral arterial disease (PAD) before and after interventional revascularisation. Methods Twenty-nine consecutive patients with symptomatic PAD of the lower extremities requiring interventional revascularisation were assessed prospectively. All patients underwent a CTP scan of the lower leg, and hemodynamic and angiographic assessment, before and after intervention. Ankle-brachial pressure index (ABI) was determined. CTP parameters were calculated with a perfusion software, acting on a no outflow assumption. A sequential two-compartment model was used. Differences in CTP parameters were assessed with non-parametric tests. Results The cohort consisted of 24 subjects with an occlusion, and five with a high-grade stenosis. The mean blood flow before/after (BFpre and BFpost, respectively) was 7.42 ± 2.66 and 10.95 ± 6.64 ml/100 ml*min−1. The mean blood volume before/after (BVpre and BVpost, respectively) was 0.71 ± 0.35 and 1.25 ± 1.07 ml/100 ml. BFpost and BVpost were significantly higher than BFpre and BVpre in the treated limb (p = 0.003 and 0.02, respectively), but not in the untreated limb (p = 0.641 and 0.719, respectively). Conclusions CTP seems feasible for assessing hemodynamic differences in calf muscles before and after revascularisation in patients with symptomatic PAD. We could show that CTP parameters BF and BV are significantly increased after revascularisation of the symptomatic limb. In the future, this quantitative method might serve as a non-invasive method for surveillance and therapy control of patients with peripheral arterial disease. Key Points • CTP imaging of the lower limb in patients with symptomatic PAD seems feasible for assessing hemodynamic differences before and after revascularisation in PAD patients. • This quantitative method might serve as a non-invasive method, for surveillance and therapy control of patients with PAD.

scholarly journals Unilateral lateral rectus recession is an effective surgery for intermittent exotropia in young children

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Oriel Spierer ◽  
Abraham Spierer
Keyword(s):  
Young Children ◽  
Success Rate ◽  
Lateral Rectus ◽  
Intermittent Exotropia ◽  
Age At Surgery ◽  
Surgical Methods ◽  
Before And After ◽  
The Mean ◽  
Consecutive Esotropia

Abstract Background Different surgical methods have been suggested for the correction of intermittent exotropia. Unilateral lateral rectus recession has been described as a surgical alternative for small and moderate-angle exotropia. In general, previous studies did not focus on the outcomes of unilateral lateral rectus recession in young children with intermittent exotropia. The purpose of this study is to evaluate the surgical outcomes of unilateral lateral rectus recession in the treatment of moderate-angle exotropia (≤ 25 PD (prism diopters)) in children. Methods The charts of all patients younger than 12 years of age with moderate-angle exotropia (up to 25 PD) who were operated during the years 2006–2018 were retrospectively reviewed. Fifty-eight patients underwent unilateral lateral rectus recession and had a minimum follow up of 6 months. The angle of exotropia (PD) before and after surgery and the success rate were documented. Results Mean age at surgery was 6.4 ± 1.9 (range 3.5–11.0) years. Exotropia improved from a preoperative angle of 21.4 ± 4.0 PD to 3.5 ± 5.9 PD postoperatively (p < 0.001). Success rate, defined as deviation of ≤ 10 PD, was achieved in 86.2%. There were 2 (3.4%) cases of overcorrection (consecutive esotropia). There were no intra- or postoperative complications. The mean follow-up duration after surgery was 2.3 ± 1.7 years. Conclusions In children with moderate angle exotropia, good postoperative success rate was achieved by performing unilateral lateral rectus recession.

Evaluation of Changes in Depression Levels of Bruxism Patients Treated With Botulinum Toxin-A

2021 ◽  
pp. 232020682110065
Author(s):  
Deniz Erdil ◽  
Nilsun Bagis ◽  
Hakan Eren ◽  
Melike Camgoz ◽  
Kaan Orhan
Keyword(s):  
Botulinum Toxin ◽  
Botulinum Toxin A ◽  
Age Groups ◽  
Treatment Method ◽  
Definitive Treatment ◽  
Toxin A ◽  
Physiological Factors ◽  
Before And After ◽  
The Mean ◽  
Post Hoc

Aim: Bruxism is defined as the involuntary recurrent masticatory muscle activity characterized by gnashing, grinding, clenching of teeth, and/or pushing the mandible. Factors creating its etiology are peripheral (morphological) or central (physiopathological and physiological), and exogenous. Recently, among physiological factors, depression and bruxism were considered to be related. A definitive treatment method does not exist for bruxism; however, botulinum toxin-A (BT-A) application is an up-to-date and effective way of treatment. The present study is aimed to evaluate the levels of depression in bruxism patients treated with BT-A application. Materials and Methods: A total of 25 individuals (23 females and 2 males) who were diagnosed as bruxism patients were included in the study. 25 U of BT-A for each masseter muscle was injected into the patients. Patients were prospectively observed for a possible change in depression levels by using Beck’s Depression Inventory. The inventory was implemented before and six months after the BT-A application. Depression levels before and six months after the injection were compared. A paired t-test was used to compare “before” and “after” treatment values. One-way analysis of variance and post-hoc Tukey tests were used to evaluate the change in Beck’s Depression Inventory scores according to age groups. Results: The mean total score was 7.80 ± 8.10 before the treatment and 7.16 ± 6.52 six months after the treatment. The decrease in the mean score was not statistically significant ( P > .05). Conclusion: In conclusion, despite the decrease in the mean Beck’s Depression Inventory scores, a statistically significant decrease in the depression levels of patients was not observed.

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