scholarly journals Real-time high-speed mobility management

2021 ◽  
Vol 24 (3) ◽  
pp. 1534
Author(s):  
Ahmed Abdelsalam Abuelgasim ◽  
Mohamed Khalafalla Hassan ◽  
Mutaz Hamed Khairi ◽  
Muhammad Nadzir Marsono ◽  
Kamaludin Mohamad Yusof
Keyword(s):  
High Speed ◽  
Real Life ◽  
Cell Types ◽  
Network Coverage ◽  
Measurement Monitoring ◽  
Term Evolution ◽  
Mobility System ◽  
Multiple Cell ◽  
Better Than

High-speed mobility system has now become a serious concern for mobile operators due to the large frameworks of a heterogeneous network made up of multiple cell types and different frequency bands. Handover (HO) is conducted in a real-life scenario when the user equipment (UE) moves from one network coverage to another by performing proper measurement with high speed. HO breakdown and call loss are observed due to a high speed; thus, high-speed mobility system needs improvement by using the UE speed as one of the key measurement monitoring criteria for the long-term evolution (LTE) network. Vendor consultation has been considered in this paper in addition to real drive test measurement in highways. Results have shown that velocity has a direct impact on the handover quality and overall timing. Results also demonstrate that 120 km/h measurement is better than 140 km/h as UE speed.

scholarly journals COVID-19-related anosmia is associated with viral persistence and inflammation in human olfactory epithelium and brain infection in hamsters

2021 ◽  
pp. eabf8396
Author(s):  
Guilherme Dias de Melo ◽  
Françoise Lazarini ◽  
Sylvain Levallois ◽  
Charlotte Hautefort ◽  
Vincent Michel ◽  
...  
Keyword(s):  
Olfactory Epithelium ◽  
Cell Types ◽  
Brain Infection ◽  
Olfactory Neuroepithelium ◽  
Optimal Medical Management ◽  
Infected Cells ◽  
Multiple Cell ◽  
Lung Pathogenesis ◽  
Taste Dysfunction

Whereas recent investigations have revealed viral, inflammatory and vascular factors involved in SARS-CoV-2 lung pathogenesis, the pathophysiology of neurological disorders in COVID-19 remains poorly understood. Olfactory and taste dysfunction are common in COVID-19, especially in mildly symptomatic patients. Here, we conducted a virologic, molecular, and cellular study of the olfactory neuroepithelium of seven patients with COVID-19 presenting with acute loss of smell. We report evidence that the olfactory neuroepithelium may be a major site of SARS-CoV2 infection with multiple cell types, including olfactory sensory neurons, support cells, and immune cells, becoming infected. SARS-CoV-2 replication in the olfactory neuroepithelium was associated with local inflammation. Furthermore, we showed that SARS-CoV-2 induced acute anosmia and ageusia in golden Syrian hamsters, lasting as long as the virus remained in the olfactory epithelium and the olfactory bulb. Finally, olfactory mucosa sampling from patients showing long-term persistence of COVID-19-associated anosmia revealed the presence of virus transcripts and of SARS-CoV-2-infected cells, together with protracted inflammation. SARS-CoV-2 persistence and associated inflammation in the olfactory neuroepithelium may account for prolonged or relapsing symptoms of COVID-19, such as loss of smell, which should be considered for optimal medical management of this disease.

scholarly journals A statistical study of the long-term evolution of coronal hole properties as observed by SDO

2020 ◽  
Vol 638 ◽  
pp. A68 ◽  
Author(s):  
S. G. Heinemann ◽  
V. Jerčić ◽  
M. Temmer ◽  
S. J. Hofmeister ◽  
M. Dumbović ◽  
...  
Keyword(s):  
Solar Wind ◽  
Magnetic Flux ◽  
Coronal Hole ◽  
High Speed ◽  
Coronal Holes ◽  
Magnetic Flux Density ◽  
High Speed Stream ◽  
Term Evolution ◽  
Hole Area

Context. Understanding the evolution of coronal holes is especially important when studying the high-speed solar wind streams that emanate from them. Slow- and high-speed stream interaction regions may deliver large amounts of energy into the Earth’s magnetosphere-ionosphere system, cause geomagnetic storms, and shape interplanetary space. Aims. By statistically investigating the long-term evolution of well-observed coronal holes we aim to reveal processes that drive the observed changes in the coronal hole parameters. By analyzing 16 long-living coronal holes observed by the Solar Dynamic Observatory, we focus on coronal, morphological, and underlying photospheric magnetic field characteristics, and investigate the evolution of the associated high-speed streams. Methods. We use the Collection of Analysis Tools for Coronal Holes to extract and analyze coronal holes using 193 Å EUV observations taken by the Atmospheric Imaging Assembly as well as line–of–sight magnetograms observed by the Helioseismic and Magnetic Imager. We derive changes in the coronal hole properties and look for correlations with coronal hole evolution. Further, we analyze the properties of the high–speed stream signatures near 1AU from OMNI data by manually extracting the peak bulk velocity of the solar wind plasma. Results. We find that the area evolution of coronal holes shows a general trend of growing to a maximum followed by a decay. We did not find any correlation between the area evolution and the evolution of the signed magnetic flux or signed magnetic flux density enclosed in the projected coronal hole area. From this we conclude that the magnetic flux within the extracted coronal hole boundaries is not the main cause for its area evolution. We derive coronal hole area change rates (growth and decay) of (14.2 ± 15.0)×108 km2 per day showing a reasonable anti-correlation (ccPearson = −0.48) to the solar activity, approximated by the sunspot number. The change rates of the signed mean magnetic flux density (27.3 ± 32.2 mG day−1) and the signed magnetic flux (30.3 ± 31.5 1018 Mx day−1) were also found to be dependent on solar activity (ccPearson = 0.50 and ccPearson = 0.69 respectively) rather than on the individual coronal hole evolutions. Further we find that the relation between coronal hole area and high-speed stream peak velocity is valid for each coronal hole over its evolution, but we see significant variations in the slopes of the regression lines.

scholarly journals Optimization of LTE Network Coverage

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Fu Yanbo
Keyword(s):  
Mobile Communications ◽  
Network Performance ◽  
High Mobility ◽  
Network Coverage ◽  
Lte Network ◽  
Term Evolution ◽  
High Spectral Efficiency ◽  
Mobile Communication Technology ◽  
New Generation

The trend of mobile, broadband and IP is becoming more and more prominent. Mobile communication technology is now in acritical period in the evolution of network technology. As such, LTE (Long Term Evolution) comes to light. LTE serves as a unified standardfor the new generation of mobile communications, equipped with high spectral efficiency, high peak rate, high mobility, flat networkarchitecture and other advantages. Huawei has played a very important role in the commercialization of LTE. As a sponsor of NGMN,Huawei has been actively involved in the research of some key projects of NGMN, such as network self-optimization, system architectureand Network performance evaluation and so on. This paper mainly introduces the problems encountered in the optimization of LTEnetwork coverage, the practical problems encountered by the LTE project team in Qingdao and the analysis and solutions to the problems.At the same time, this paper discusses in detail on the LTE network optimization process.

scholarly journals High Speed Mobility Management Performance in a Real LTE Scenario

2020 ◽  
Vol 10 (1) ◽  
pp. 5175-5179
Author(s):  
A. A. M. K. Abuelgasim ◽  
K. M. Yusof
Keyword(s):  
High Risk ◽  
Mobility Management ◽  
High Speed ◽  
Field Measurements ◽  
Mobile Operator ◽  
Seamless Connectivity ◽  
Term Evolution ◽  
Network Technologies

This paper discusses the mobility management for high-speed users, which is a crucial challenge for all mobile operators, especially when users are moving vertically across different network technologies. Mobility, also known as seamless connectivity, is directly influencing the quality of service (QoS). Mobility management-Handover (HO) performance was evaluated by field measurements of a Long Term Evolution (LTE) network of a mobile operator in the Middle East. Drive test measurements were used to analyze the results of different high-speed scenarios. User Equipment (UE) with high speed of 80-140km/h causes a high risk of failure of seamless connectivity as the HO procedure timing is longer than for UE with smaller speed. HO failure and call drop may occur when UE is moving with high speed across two adjacent cells in highways. During measurements, HO failure occurred when UE speed was 140km/h, and HO preparation timing increased when UE speed increased.

scholarly journals Analysis of multispectral imaging with the AstroPath platform informs efficacy of PD-1 blockade

Science ◽  
2021 ◽  
Vol 372 (6547) ◽  
pp. eaba2609
Author(s):  
Sneha Berry ◽  
Nicolas A. Giraldo ◽  
Benjamin F. Green ◽  
Tricia R. Cottrell ◽  
Julie E. Stein ◽  
...  
Keyword(s):  
Multispectral Imaging ◽  
Expression Patterns ◽  
Cell Types ◽  
Term Survival ◽  
Multiple Parameters ◽  
Tissue Sections ◽  
Programmed Cell Death 1 ◽  
Multiple Cell ◽  
Independent Cohort

Next-generation tissue-based biomarkers for immunotherapy will likely include the simultaneous analysis of multiple cell types and their spatial interactions, as well as distinct expression patterns of immunoregulatory molecules. Here, we introduce a comprehensive platform for multispectral imaging and mapping of multiple parameters in tumor tissue sections with high-fidelity single-cell resolution. Image analysis and data handling components were drawn from the field of astronomy. Using this “AstroPath” whole-slide platform and only six markers, we identified key features in pretreatment melanoma specimens that predicted response to anti–programmed cell death-1 (PD-1)–based therapy, including CD163+PD-L1– myeloid cells and CD8+FoxP3+PD-1low/mid T cells. These features were combined to stratify long-term survival after anti–PD-1 blockade. This signature was validated in an independent cohort of patients with melanoma from a different institution.

Long term evolution in high speed railway environments: Feasibility and challenges

2013 ◽  
Vol 18 (2) ◽  
pp. 237-253 ◽  
Author(s):  
Jaime Calle-Sanchez ◽  
Mariano Molina-Garcia ◽  
Jose I. Alonso ◽  
Alfonso Fernandez-Duran
Keyword(s):  
High Speed ◽  
Long Term Evolution ◽  
High Speed Railway ◽  
Term Evolution

scholarly journals Investigating the long-term evolution of subtropical ozone profiles applying ground-based FTIR spectrometry

2012 ◽  
Vol 5 (11) ◽  
pp. 2917-2931 ◽  
Author(s):  
O. E. García ◽  
M. Schneider ◽  
A. Redondas ◽  
Y. González ◽  
F. Hase ◽  
...  
Keyword(s):  
Time Series ◽  
Line Shape ◽  
Long Term Evolution ◽  
Term Evolution ◽  
Ozone Profile ◽  
Instrumental Line ◽  
Temperature Retrieval ◽  
Linear Trends ◽  
Better Than

Abstract. This study investigates the long-term evolution of subtropical ozone profile time series (1999–2010) obtained from ground-based FTIR (Fourier Transform InfraRed) spectrometry at the Izaña Observatory ozone super-site. Different ozone retrieval strategies are examined, analysing the influence of an additional temperature retrieval and different constraints. The theoretical assessment reveals that the FTIR system is able to resolve four independent ozone layers with a precision of better than 6% in the troposphere and of better than 3% in the lower, middle and upper stratosphere. This total error includes the smoothing error, which dominates the random error budget. Furthermore, we estimate that the measurement noise as well as uncertainties in the applied atmospheric temperature profiles and instrumental line shape are leading error sources. We show that a simultaneous temperature retrieval can significantly reduce the total random errors and that a regular determination of the instrumental line shape is important for producing a consistent long-term dataset. These theoretical precision estimates are empirically confirmed by daily intercomparisons with Electro Chemical Cell (ECC) sonde profiles. In order to empirically document the long-term stability of the FTIR ozone profile data we compare the linear trends and seasonal cycles as obtained from the FTIR and ECC time series. Concerning seasonality, in winter both techniques observe stratospheric ozone profiles that are typical middle latitude profiles (low tropopause, low ozone maximum concentrations) and in summer/autumn profiles that are typical tropical profiles (high tropopause, high maximum concentrations). The linear trends estimated from the FTIR and the ECC datasets agree within their error bars. For the FTIR time series, we observe a significant negative trend in the upper troposphere/lower stratosphere of about −0.2% yr−1 and a significant positive trend in the middle and upper stratosphere of about +0.3% yr−1 and +0.4% yr−1, respectively. Identifying such small trends is a difficult task for any measurement technique. In this context, super-sites applying different techniques are very important for the detection of reliable ozone trends.

scholarly journals A New Organotypic Culture of Adipose Tissue Fragments Maintains Viable Mature Adipocytes for a Long Term, Together with Development of Immature Adipocytes and Mesenchymal Stem Cell-Like Cells

Endocrinology ◽  
2008 ◽  
Vol 149 (10) ◽  
pp. 4794-4798 ◽  
Author(s):  
Emiko Sonoda ◽  
Shigehisa Aoki ◽  
Kazuyoshi Uchihashi ◽  
Hidenobu Soejima ◽  
Sachiko Kanaji ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Organotypic Culture ◽  
Three Dimensional ◽  
Collagen Gel ◽  
Cell Types ◽  
Ppar Γ ◽  
Tnf Α ◽  
Multiple Cell ◽  
Related Agent

Adipose tissue that consists of mature and immature adipocytes is suggested to contain mesenchymal stem cells (MSCs), but a culture system for analyzing their cell types within the tissue has not been established. Here we show that three-dimensional collagen gel culture of rat sc adipose tissue fragments maintained viable mature adipocytes for a long term, producing immature adipocytes and MSC-like cells from the fragments, using immunohistochemistry, ELISA, and real time RT-PCR. Bromodeoxyuridine uptake of mature adipocytes was detected. Adiponectin and leptin, and adipocyte-specific genes of adiponectin, leptin, and PPAR-γ were detected in culture assembly, whereas the lipogenesis factor insulin (20 mU/ml) and inflammation-related agent TNF-α (2 nm) increased and decreased, respectively, all of their displays. Both spindle-shaped cell types with oil red O-positive lipid droplets and those with expression of MSC markers (CD105 and CD44) developed around the fragments. The data indicate that adipose tissue-organotypic culture retains unilocular structure, proliferative ability, and some functions of mature adipocytes, generating both immature adipocytes and CD105+/CD44+ MSC-like cells. This suggests that our method will open up a new way for studying both multiple cell types within adipose tissue and the cell-based mechanisms of obesity and metabolic syndrome.

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