scholarly journals Dynamics of the Deep Solar Photosphere at Subgranular Scales

1998 ◽  
Vol 185 ◽  
pp. 451-452
Author(s):  
A. Nesis ◽  
R. Hammer ◽  
M. Kiefer ◽  
H. Schleicher
Keyword(s):  
Granular Flow ◽  
Approximation Property ◽  
High Spatial Resolution ◽  
Time Span ◽  
Solar Photosphere ◽  
Vacuum Tower ◽  
Solar Granulation ◽  
Wavelet Techniques ◽  
The Relationship ◽  
Signal Approximation

Extending our previous studies of the dynamics of solar granulation (Nesis et al., 1997) we investigated the relationship between granular flow and the emergence of turbulence in the deep photosphere. Our main goal is to explore if such a relationship exists, and if so, to define it quantitatively. To this end we take advantage of the excellent signal approximation property of wavelets. The material for the present work is a series of spectrograms of high spatial resolution covering a time span of 12 min. They were taken at the center of the solar disk with the German Vacuum Tower Telescope in Izaña (Tenerife, Spain) in 1994, and include several absorption lines of different strengths; for more details see Nesis et al. (1997). The spectrograms were digitized and processed with wavelet techniques and regression analysis, in order to investigate the granular convective flow, the associated turbulence, and their mutual connection.

scholarly journals The dynamics of the observed solar granulation: spatio-temporal variations of line of sight velocity and thermodynamic parameters

2014 ◽  
Vol 4 (1-2) ◽  
pp. 32-37 ◽  
Author(s):  
O. Baran
Keyword(s):  
Thermodynamic Parameters ◽  
Acoustic Waves ◽  
High Spatial Resolution ◽  
Temporal Variations ◽  
Solar Photosphere ◽  
Solar Granulation ◽  
Iron Line ◽  
Solar Convection ◽  
Spatio Temporal ◽  
Convective Cells

We investigated the dynamics of solar granulation, using the neutral iron line λ ≈ 639.3 nm profiles from high-spatial resolution observations around the centre of the solar disc, in the non-perturbed region. We reproduced spatio-temporal variations of kinematic and thermodynamic parameters of solar convection at different heights of the solar photosphere (h = −25..550 km). The acoustic waves were removed by k - ω filtration. We analysed the temporal changes of these variations within convective cells.

scholarly journals Covid-19 and acute conjunctivitis: Controversial data from a tertiary refferral Italian center

2021 ◽  
pp. 112067212199104
Author(s):  
Giuseppe D’Amico Ricci ◽  
Claudia Del Turco ◽  
Elena Belcastro ◽  
Marco Palisi ◽  
Mario R Romano ◽  
...  
Keyword(s):  
Emergency Department ◽  
Odds Ratio ◽  
Signs And Symptoms ◽  
Time Span ◽  
Nasopharyngeal Swab ◽  
Eye Disorders ◽  
Eye Examination ◽  
The Relationship ◽  
Acute Conjunctivitis ◽  
Piedmont Region

Purpose: Although acute conjunctivitis has been listed from the beginning as a possible sign of COVID-19, the likelihood of this association remains unclear. The aim of this study was to investigate the relationship between COVID-19 and conjunctivitis. Methods: In this retrospective, observational study, we recruited all patients with signs and symptoms of acute conjunctivitis seen at the Eye Emergency Department (ED), Turin Eye Hospital, between 01/01/2020 and 12/05/2020 and cross-checked our data with the Piedmont Region online COVID-19 registry in the same period. Results: Among 10,065 patients seen at our ED during the timespan considered, 88 underwent a nasopharyngeal swab (NS) for SARS-CoV-2 detection within 4 weeks before/after our examination. On average, NS was performed −0.72 ± 1.8 weeks before/after eye examination. Of the 77 patients with a negative NS, 26 (33.8%) had a diagnosis of acute conjunctivitis, whereas the remaining 51 (66.2%) had other eye disorders. Among the 11 patients with COVID-19, 7 (63,6%) had a diagnosis of acute conjunctivitis. We found a non-statistically significant increase in NS positivity rate (21.2%) among cases examined at our ED for acute conjunctivitis, compared to the NS positivity rate (7.3%) in patients examined for all other eye conditions ( p = 0.092). The Odds Ratio of having a positive NS in patients with acute conjunctivitis was 3.43 (95% I.C. = 0.9–12.8, p = 0.06). Considering online-registry data of Turin population during the same time-span, among 2441 positive NS cases only 27 (1.1%) presented with acute conjunctivitis. Conclusion: Our results do not reveal a statistically significant correlation between COVID-19 and acute conjunctivitis. Synopsis The present study analyzes retrospectively data from a tertiary eye referral center to investigate the relationship between COVID-19 infection and conjunctivitis.

scholarly journals System for Visualizing Surface Potential Distribution to Eliminate Electrostatic Charge

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4397
Author(s):  
Kazuya Kikunaga
Keyword(s):  
Surface Potential ◽  
Potential Distribution ◽  
Measurement Accuracy ◽  
High Spatial Resolution ◽  
Scanning Speed ◽  
Electrostatic Charge ◽  
Production Quality ◽  
Array Sensor ◽  
The Relationship ◽  
Non Destructive

A mixture of positive and negative static charges exists in the same plane on an insulator surface, and this can cause production quality problems at manufacturing sites. This study developed a system with a vibration array sensor to rapidly measure the surface potential distribution of an object in a non-contact and non-destructive manner and with a high spatial resolution of 1 mm. The measurement accuracy differed greatly depending on the scanning speed of the array sensor, and an optimum scanning speed of 10 mm/s enabled rapid measurements (within <3 s) of the surface potential distribution of a charged insulator (area of 30 mm × 30 mm) with an accuracy of 15%. The relationship between charge and dust on the surface was clarified to easily visualize the uneven static charges present on it and thereby eliminate static electricity.

scholarly journals AB0101 THE IMPACT OF TIME SPAN TO ACHIEVE BOOLEAN REMISSION FOR MAINTAINING DISEASE ACTIVITY AFTER ACQUISITION IN RHEUMATOID ARTHRITIS PATIENT

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1079.1-1079
Author(s):  
I. Yoshii
Keyword(s):  
Rheumatoid Arthritis ◽  
Disease Activity ◽  
Disease Duration ◽  
Remission Rate ◽  
Mean Value ◽  
Time Span ◽  
Mean Values ◽  
The Mean ◽  
The Relationship

Background:Boolean remission criteria is one most popular and stringent criteria in treating patient with rheumatoid arthritis (RA), because it may guarantees a stable clinical course after attaining remission.Objectives:Impact of time span from initiation to achieving Boolean remission on maintaining disease activity, daily activities, and quality of life after attaining Boolean remission was investigated from daily clinical practice data.Methods:685 patients with RA since August 2010 under the T2T strategy were treated. They were monitored for their TJC, SJC, PGA, EGA, CRP, and disease activity indices such as CDAI, SDAI, DAS28, and Boolean criteria at every visit. HAQ-DI score, pain score using visual analog scale (PS-VAS), and EQ-5D were also monitored, and the quality of life score (QOLS) calculated from EQ-5D was determined at every visit from the time of diagnosis (baseline).Of 685 patients, 465 patients had achieved Boolean remission >1 times, and were consecutively followed up for >3 years. These patients were enrolled in the study. Time span from the first visit to first Boolean remission was calculated. The relationship between the time span and each of background parameters, and the relationship between the time span and each of the mean values of the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at the first Boolean remission and thereafter was evaluated statistically.Patients were subsequently divided into the G ≤ 6 and G > 6 groups based on the achievement of first Boolean remission within two groups: time span G ≤ 6 months and G > 6 months. The two groups were compared with regard to the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at first visit and at the time of first Boolean remission, and the mean values of these parameters after remission were evaluated statistically. Moreover, changes of these parameters and the mean Boolean remission rate after the first remission, and SDAI remission rate at the first Boolean remission to thereafter were compared between the two groups statistically.Results:Out of 465 patients, females comprised 343 (73.7%), and the mean age was 67.8 years (range, from 21–95 years). The mean disease duration at first visit was 6.1 years (range, from 1 months–45 years). The mean follow up length was 88.1 months (range: 36–122 months; median: 85 months) and mean time span from the first visit to the first Boolean remission was 8.1 months. The mean SDAI score, HAQ score, PS-VAS, and the QOLS at first visit were 13.3, 0.467, 33.2, and 0.834, respectively. Among the study parameters, PS-VAS and QOLS were significantly correlated with the time span. For parameters at the first Boolean remission, HAQ-DI score, PS-VAS, and QOLS demonstrated significant correlation with the time span, whereas SDAI, HAQ-DI score, PS-VAS, SHS, and QOLS after the Boolean remission demonstrated significant correlation with the time span.The comparison between the G ≤ 6 and the G > 6 groups revealed that the disease duration, HAQ score, and PS-VAS at baseline in the G > 6 were significantly higher than that in the G ≤ 6 group, and QOLS in the G ≤ 6 group was significantly higher than that in the G > 6 group at baseline. Similarly, the HAQ score and PS-VAS at the first Boolean remission in the G > 6 group were significantly higher than that in the G ≤ 6 group, whereas QOLS in the G ≤ 6 group demonstrated no significant difference compared with that in the G > 6 group.The mean value of the SDAI score after the first Boolean remission in the G > 6 group was significantly higher than that in the G ≤ 6 group. Similarly, the SDAI score, HAQ score, and PS-VAS after the first Boolean remission in the G > 6 group were also significantly higher than those in the G ≤ 6 group, and the mean value of the QOLS in the G ≤ 6 group were significantly higher than that in the G > 6 group. The Boolean remission rate and SDAI remission rate after the first Boolean remission were significantly higher in the G ≤ 6 group than those in the G > 6 group.Conclusion:Attaining Boolean remission ≤ 6 months for RA has significant benefit for more stable disease control, that leads good maintenance of ADL.Disclosure of Interests:None declared

Numerical Analysis of Bridge Expansion-Induced Rail Deformation of Ballast Truck

2014 ◽  
Vol 580-583 ◽  
pp. 3208-3214 ◽  
Author(s):  
Zhen Wei Xiong ◽  
Xin Ling Liang ◽  
Xian Xing Dai ◽  
Ping Wang
Keyword(s):  
Granular Flow ◽  
Element Model ◽  
Discrete Element Model ◽  
Board Structure ◽  
Vertical Deformation ◽  
Two Dimensional ◽  
Running Safety ◽  
Bridge Plate ◽  
Ballast Track ◽  
The Relationship

when the ballast track stretch with the bridge, ballast which is near expansion joint will move confusedly. As a result, rail produced vertical deformation. The deformation will affect the running safety and comfortability of train. At present, there are two kinds of treatments which are cover board structure and baffle structure to deal ballast’s movement. Aiming at the different modes of stretching when the two kinds of structures and different arrangement condition of bridge plate are applied, the rail-sleeper-ballast discrete element model is developed by the method of two-dimensional granular flow. The relationship between rail deformation and bridge expansion is analyzed on the foundation of the model. Results show as flows: when bridge extends or shortens, rail always produced upwarp deformation. Bridge plate should arrange asymmetrically. Like this, the rail deformation decrease by 40%. And adopting the baffle structure can effectively reduce the influence of bridge expansion in ballast truck.

scholarly journals Assessing the relationship between environmental factors and malaria vector breeding sites in Swaziland using multi-scale remotely sensed data

2015 ◽  
Vol 10 (1) ◽  
Author(s):  
Sabelo Nick Dlamini ◽  
Jonas Franke ◽  
Penelope Vounatsou
Keyword(s):  
Environmental Factors ◽  
Spatial Resolution ◽  
Malaria Vector ◽  
Land Surface ◽  
High Spatial Resolution ◽  
Remotely Sensed ◽  
Remotely Sensed Data ◽  
Breeding Sites ◽  
Multi Scale ◽  
The Relationship

Many entomological studies have analyzed remotely sensed data to assess the relationship between malaria vector distribution and the associated environmental factors. However, the high cost of remotely sensed products with high spatial resolution has often resulted in analyses being conducted at coarse scales using open-source, archived remotely sensed data. In the present study, spatial prediction of potential breeding sites based on multi-scale remotely sensed information in conjunction with entomological data with special reference to presence or absence of larvae was realized. Selected water bodies were tested for mosquito larvae using the larva scooping method, and the results were compared with data on land cover, rainfall, land surface temperature (LST) and altitude presented with high spatial resolution. To assess which environmental factors best predict larval presence or absence, Decision Tree methodology and logistic regression techniques were applied. Both approaches showed that some environmental predictors can reliably distinguish between the two alternatives (existence and non-existence of larvae). For example, the results suggest that larvae are mainly present in very small water pools related to human activities, such as subsistence farming that were also found to be the major determinant for vector breeding. Rainfall, LST and altitude, on the other hand, were less useful as a basis for mapping the distribution of breeding sites. In conclusion, we found that models linking presence of larvae with high-resolution land use have good predictive ability of identifying potential breeding sites.

scholarly journals High-Resolution Observations of Emerging Magnetic Fields and Flux Tubes in Active Region Photosphere

1990 ◽  
Vol 138 ◽  
pp. 147-152 ◽  
Author(s):  
T. Tarbell ◽  
S. Ferguson ◽  
Z. Frank ◽  
R. Shine ◽  
A. Title ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Active Region ◽  
Solar Observatory ◽  
Disk Center ◽  
Line Center ◽  
Solar Photosphere ◽  
Flux Tubes ◽  
National Solar Observatory ◽  
La Palma ◽  
The Relationship

On 29 September 1988, filtergrams of the solar photosphere with excellent resolution (0.3 to 0.5 arcsecond) were obtained at the Swedish Solar Observatory on La Palma, Canary Islands. An outstanding 2.5 hour run of digital filtergram observations was obtained, looking at a small area within an active region near disk center. On 6 August 1987, an 80 minute run of similar observations was obtained at the Vacuum Tower Telescope of the National Solar Observatory at Sacramento Peak. Digital and video movies have been made of Dopplergrams, magnetograms, line center, continuum, and white light images. Several examples of magnetic field emergence and formation of flux tubes can be studied in detail in the movies. The relationship between photospheric bright points, “filigree”, the line center brightness, and the magnetic field has been established for individual images in analysis to date.

Polyelectrolyte Age and N-Nitrosodimethylamine Formation in Drinking Water Treatment

2003 ◽  
Vol 38 (4) ◽  
pp. 719-735 ◽  
Author(s):  
Keith D. Kohut ◽  
Susan A. Andrews
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Statistical Evaluation ◽  
Drinking Water Treatment ◽  
Order Reaction ◽  
Time Span ◽  
Two Phase ◽  
First Order ◽  
The Relationship ◽  
Phase Process

Abstract Polydiallyldimethylammonium chloride (polyDADMAC) and epichlorohydrin-dimethylamine (Epi-DMA) stock olutions were prepared, stored for varying amounts of time, and used in bench-scale simulations of coagulation/flocculation/sedimentation to determine whether polymer stock age had an influence on NDMA yields. Stock solution ages ranged from under one hour to fifty hours. PolyDADMAC stock age did not significantly affect NDMA production. Epi-DMA stock age significantly increased NDMA production over a time span of 0 to 5 hours, but not from 5 to 50 hours. The relationship between the change in NDMA yields and Epi-DMA stock solution age may be a first-order reaction or a two-phase process. Statistical evaluation of the data available supports both theories.

Novel Approach to Quantitative Depth Profiling of Surfaces Using ATR/FT-IR Measurements

1993 ◽  
Vol 47 (7) ◽  
pp. 973-981 ◽  
Author(s):  
Jiangbing Huang ◽  
Marek W. Urban
Keyword(s):  
High Spatial Resolution ◽  
Depth Profiling ◽  
Computation Time ◽  
Linear Interpolation ◽  
Variable Parameters ◽  
Novel Approach ◽  
Ft Ir ◽  
Reflection Theory ◽  
Reflectivity Data ◽  
The Relationship

Reflection theory for step-wise stratified media is applied to establish the relationship between the reflectivity data obtained from ATR/FT-IR surface depth profiling experiments and the concentration at a given surface depth. In spite of the mathematical complexity of the process, an unknown surface depth profiling can be calculated by using a linear interpolation, or by applying a function with variable parameters. Due to limited assumptions and fairly reasonable computation time, even when the sample is finely divided to achieve high spatial resolution, the linear interpolation approach seems to be particularly advantageous. The proposed methodology is tested for the distribution of surfactant molecules and calculations of the surface depth profiles in latex thin films.

The Coefficient of Restitution of Spheroid Particles Impacting on a Wall—Part I: Experiments

2018 ◽  
Vol 85 (4) ◽  
Author(s):  
Ming Hu ◽  
Yrjö Jun Huang ◽  
Fei Wang ◽  
Martin Smedstad Foss
Keyword(s):  
Inclination Angle ◽  
Granular Flow ◽  
High Speed ◽  
Contact Point ◽  
Prolate Spheroid ◽  
Spherical Particles ◽  
Dimensionless Number ◽  
Discrete Element Modeling ◽  
The Relationship ◽  
Spheroid Particle

Coefficients of restitution (CoR) is used to scale the kinetic energy dissipation, which is a necessary parameter for discrete element modeling simulations of granular flow. Differences from the collision of spherical particles, CoRs of spheroid particle are affected not only by materials, particle size, and impacting velocity, but also by the contact inclination angle of the particle. This article presents our experimental investigation to measure the velocities of translation and rotation using high-speed camera and calculate the CoR in normal direction of prolate spheroid particles impacting flat targets. The results show that this CoR of a prolate spheroid particle is composed of two parts, translation and rotation. The effect from the contact inclination angle is not obvious for a given velocity. When the contact point is close to a pole, the first part plays a major role. On the contrary, the second part dominates the CoR, when the contact point is close to the equator. A dimensionless number, e*, is defined to scale the proportion of velocity due to rotation in the total rebound velocity at the contact point. The relationship between the contact inclination angle, ϕ, and e* for 25 deg < ϕ < 90 deg is given in this article.

Sign in / Sign up

Export Citation Format

Share Document