scholarly journals Insights on the mutational landscape of the SARS-CoV-2 Omicron variant

2021 ◽  
Author(s):  
Nathaniel L. Miller ◽  
Thomas Clark ◽  
Rahul Raman ◽  
Ram Sasisekharan
Keyword(s):  
Network Analysis ◽  
Conformational Stability ◽  
Mutational Landscape ◽  
Class 1 ◽  
Amino Acid Interaction ◽  
Global Concern ◽  
Therapeutic Monoclonal Antibodies ◽  
The Impact ◽  
Antibody Epitopes ◽  
Mutation Analyses

The SARS-COV2 Omicron variant has sparked global concern due to the possibility of enhanced transmissibility and escape from vaccines and therapeutics. In this study, we describe the mutational landscape of the Omicron variant using amino acid interaction (AAI) networks. AAI network analysis is particularly well suited for interrogating the impact of constellations of mutations as occur on Omicron that may function in an epistatic manner. Our analyses suggest that as compared to previous variants of concern, the Omicron variant has increased antibody escape breadth due to mutations in class 3 and 4 antibody epitopes as well as increased escape depth due to accumulated mutations in class 1 antibody epitopes. We note certain RBD mutations that might further enhance Omicron escape, and in particular advise careful surveillance of two subclades bearing R346S/K mutations. Further, AAI network analysis suggests that the function of certain therapeutic monoclonal antibodies may be disrupted by Omicron mutations as a result of the cumulative indirect perturbations to the epitope surface properties, despite point-mutation analyses suggesting these antibodies are tolerant of the set of Omicron mutations in isolation. Finally, for several Omicron mutations that do not appear to contribute meaningfully to antibody escape, we find evidence for a plausible role in enhanced transmissibility via disruption of RBD-down conformational stability at the RBD-RBD interface.

scholarly journals Quantitative Dynamics Effects of Belt and Road Economies Trade Using Structural Gravity and Neural Networks

SAGE Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 215824402110326
Author(s):  
Koffi Dumor ◽  
Li Yao ◽  
Jean-Paul Ainam ◽  
Edem Koffi Amouzou ◽  
Williams Ayivi
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Network Analysis ◽  
Bilateral Trade ◽  
Belt And Road Initiative ◽  
Neural Network Analysis ◽  
Analysis Techniques ◽  
Belt And Road ◽  
The Impact ◽  
Trade Partners

Recent research suggests that China’s Belt and Road Initiative (BRI) would improve the bilateral trade between China and its partners. This article uses detailed bilateral export data from 1990 to 2017 to investigate the impact of China’s BRI on its trade partners using neural network analysis techniques and structural gravity model estimations. Our main findings suggest that the BRI countries would raise exports by a modest 5.053%. This indicates that export and network upgrades should be considered from economic and policy perspectives. The results also show that neural networks is more robust compared with structural gravity framework.

scholarly journals The Impact on Infectivity and Neutralization Efficiency of SARS-CoV-2 Lineage B.1.351 Pseudovirus

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 633
Author(s):  
Yeong Jun Kim ◽  
Ui Soon Jang ◽  
Sandrine M. Soh ◽  
Joo-Youn Lee ◽  
Hye-Ra Lee
Keyword(s):  
South Africa ◽  
Monoclonal Antibodies ◽  
Cell Fusion ◽  
Receptor Binding ◽  
Neutralizing Antibodies ◽  
Receptor Binding Domain ◽  
Viral Spread ◽  
New Variant ◽  
Global Concern ◽  
The Impact

A new variant of SARS-CoV-2 B.1.351 lineage (first found in South Africa) has been raising global concern due to its harboring of multiple mutations in the spike that potentially increase transmissibility and yield resistance to neutralizing antibodies. We here tested infectivity and neutralization efficiency of SARS-CoV-2 spike pseudoviruses bearing particular mutations of the receptor-binding domain (RBD) derived either from the Wuhan strains (referred to as D614G or with other sites) or the B.1.351 lineage (referred to as N501Y, K417N, and E484K). The three different pseudoviruses B.1.351 lineage related significantly increased infectivity compared with other mutants that indicated Wuhan strains. Interestingly, K417N and E484K mutations dramatically enhanced cell–cell fusion than N501Y even though their infectivity were similar, suggesting that K417N and E484K mutations harboring SARS-CoV-2 variant might be more transmissible than N501Y mutation containing SARS-CoV-2 variant. We also investigated the efficacy of two different monoclonal antibodies, Casirivimab and Imdevimab that neutralized SARS-CoV-2, against several kinds of pseudoviruses which indicated Wuhan or B.1.351 lineage. Remarkably, Imdevimab effectively neutralized B.1.351 lineage pseudoviruses containing N501Y, K417N, and E484K mutations, while Casirivimab partially affected them. Overall, our results underscore the importance of B.1.351 lineage SARS-CoV-2 in the viral spread and its implication for antibody efficacy.

scholarly journals Seizure outcome in temporal glioblastoma surgery: lobectomy as a supratotal resection regime outclasses conventional gross-total resection

2021 ◽  
Author(s):  
Valeri Borger ◽  
Motaz Hamed ◽  
Inja Ilic ◽  
Anna-Laura Potthoff ◽  
Attila Racz ◽  
...  
Keyword(s):  
Tumor Resection ◽  
Temporal Lobectomy ◽  
Secondary Outcome ◽  
Seizure Outcome ◽  
Seizure Freedom ◽  
Secondary Outcome Measure ◽  
Total Resection ◽  
Class 1 ◽  
Postoperative Seizure ◽  
The Impact

Abstract Introduction The postoperative seizure freedom represents an important secondary outcome measure in glioblastoma surgery. Recently, supra-total glioblastoma resection in terms of anterior temporal lobectomy (ATL) has gained growing attention with regard to superior long-term disease control for temporal-located glioblastoma compared to conventional gross-total resections (GTR). However, the impact of ATL on seizure outcome in these patients is unknown. We therefore analyzed ATL and GTR as differing extents of resection in regard of postoperative seizure control in patients with temporal glioblastoma and preoperative symptomatic seizures. Methods Between 2012 and 2018, 33 patients with preoperative seizures underwent GTR or ATL for temporal glioblastoma at the authors’ institution. Seizure outcome was assessed postoperatively and 6 months after tumor resection according to the International League Against Epilepsy (ILAE) classification and stratified into favorable (ILAE class 1) versus unfavorable (ILAE class 2–6). Results Overall, 23 out of 33 patients (70%) with preoperative seizures achieved favorable seizure outcome following resection of temporal located glioblastoma. For the ATL group, postoperative seizure freedom was present in 13 out of 13 patients (100%). In comparison, respective rates for the GTR group were 10 out of 20 patients (50%) (p = 0.002; OR 27; 95% CI 1.4–515.9). Conclusions ATL in terms of a supra-total resection strategy was associated with superior favorable seizure outcome following temporal glioblastoma resection compared to GTR. Regarding above mentioned survival benefit following ATL compared to GTR, ATL as an aggressive supra-total resection regime might constitute the surgical modality of choice for temporal-located glioblastoma.

Selection of AmpC β-lactamase variants and metallo-β-lactamases leading to ceftolozane/tazobactam and ceftazidime/avibactam-resistance during treatment of MDR/XDR Pseudomonas aeruginosa infections

2021 ◽  
Author(s):  
Alba Ruedas-López ◽  
Isaac Alonso García ◽  
Cristina Lasarte-Monterrubio ◽  
Paula Guijarro-Sánchez ◽  
Eva Gato ◽  
...  
Keyword(s):  
3D Models ◽  
Resistance Mechanisms ◽  
Class 1 ◽  
Long Read ◽  
Cephalosporin Resistance ◽  
One Year ◽  
Clinical Conditions ◽  
Hybrid Assemblies ◽  
Chromosomal Mutations ◽  
The Impact

Infections caused by ceftolozane/tazobactam and ceftazidime/avibactam-resistant P. aeruginosa infections are an emerging concern. We aimed to analyze the underlying ceftolozane/tazobactam and ceftazidime/avibactam resistance mechanisms in all MDR/XDR P. aeruginosa isolates recovered during one year (2020) from patients with a documented P. aeruginosa infection. Fifteen isolates showing ceftolozane/tazobactam and ceftazidime/avibactam resistance were evaluated. Clinical conditions, previous positive cultures and β-lactams received in the previous month were reviewed for each patient. MICs were determined by broth microdilution. MLSTs and resistance mechanisms were determined using short- and long-read WGS. The impact of PDCs on β-lactam resistance was demonstrated by cloning into an ampC -deficient PAO1 derivative (PAOΔC) and construction of 3D models. Genetic support of acquired β-lactamases was determined in silico from high-quality hybrid assemblies. In most cases, the isolates were recovered after treatment with ceftolozane/tazobactam or ceftazidime/avibactam. Seven isolates from different STs owed their β-lactam resistance to chromosomal mutations and all displayed specific substitutions in PDC: Phe121Leu and Gly222Ser, Pro154Leu, Ala201Thr, Gly214Arg, ΔGly203-Glu219 and Glu219Lys. In the other eight isolates, the ST175 clone was overrepresented (6 isolates) and associated with IMP-28 and IMP-13, whereas two ST1284 isolates produced VIM-2. The cloned PDCs conferred enhanced cephalosporin resistance. 3D PDC models revealed rearrangements affecting residues involved in cephalosporin hydrolysis. Carbapenemases were chromosomal (VIM-2) or plasmid-borne (IMP-28, IMP-13), and associated with class-1 integrons located in Tn402-like transposition modules. Our findings highlight that cephalosporin/ß-lactamase inhibitors are potential selectors of MDR/XDR P. aeruginosa strains producing PDC variants or metallo-ß-lactamases. Judicious use of these agents is encouraged.

Cardiac Health Indicators in Critical COVID-19 Cases

2021 ◽  
Vol 7 (1) ◽  
pp. 1-6
Author(s):  
Sultan Alasmari ◽  
Mohammed Makkawi ◽  
Mutaib M Mashraqi ◽  
Saleh Alqahtani ◽  
Mustafa Alqahtani ◽  
...  
Keyword(s):  
Creatine Phosphokinase ◽  
Health Indicators ◽  
Total Serum ◽  
Healthy Individuals ◽  
Icu Patients ◽  
Cardiac Health ◽  
Serum Creatine Phosphokinase ◽  
Global Concern ◽  
Asir Region ◽  
The Impact

Coronavirus disease-2019 (COVID-19) is an infectious disease that has spread worldwide and led to ongoing global concern. The pandemic prompted researchers to examine the impact of COVID-19 on human organs. The heart is one such organ. This study investigates the possible prediction of heart condition using some biochemical markers of particularly critically ill patients referred to an intensive care unit (ICU). Results of various serum biomarkers of patients infected with COVID-19 receiving treatment in the ICU, Asir Central Hospital, Asir Region, Saudi Arabia, were extracted and compared with healthy individuals using the Mann-Whitney U test. The study showed a distinguished increase in total Serum creatine phosphokinase-Total (CPK-Total), Serum creatine phosphokinase-MP (CPK-MP) levels among COVID-19/ICU patients. But, this increase was not statistically significant. Besides, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels revealed a statistically significant increase in the infected group compared with controls. Examination of electrolytes showed a reduction in calcium median value in COVID-19/ICU patients. Data revealed a possible influence of COVID-19 on the heart. Herein, we observe significant parameters that may reflect cardiovascular injury elicited by the virus. These biomarkers possibly used to monitor the severity of disease on the cardiovascular system.

scholarly journals #GERIATRICS: AN ANALYSIS OF THE IMPACT OF THE GERIATRICS TWITTER NETWORK

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S337-S337
Author(s):  
Varun Ayyaswami ◽  
Arpan Prabhu ◽  
Steven Gambert
Keyword(s):  
Network Analysis ◽  
Geriatric Medicine ◽  
The United States ◽  
Annual Growth ◽  
Social Media Analytics ◽  
User Characteristics ◽  
Future Studies ◽  
Digital Community ◽  
Support Organizations ◽  
The Impact

Abstract Twitter connects an international community of healthcare stakeholders, potentially augmenting access to information related to geriatric medicine. The purpose of this study is to analyze the geriatric medicine Twitter network, and we hypothesize this community has substantially grown in the last six years. We analyzed all publicly available tweets including the hashtag #geriatrics from January 1, 2013-January 1, 2019 using Symplur Signals, a health care social media analytics platform. We evaluated #geriatrics metrics over time related to activity, content analysis, user characteristics, engagement, and network analysis. A total of 159,008 tweets (containing 42.8% re-tweets) with the hashtag #geriatrics were written by 29,443 users, resulting in 393.6 million impressions. The number of tweets increased from 9,705 in 2013 to 39,151 in 2018 (32.2% compound annual growth); users increased from 3,366 in 2013 to 29,443 in 2018 (55.3% compound annual growth). Users were primarily found in the United States, United Kingdom, and Canada. The most commonly trending topic from 2013-2015 and from 2016-2018 was ‘older adults’. The top hashtags included in tweets with #geriatrics were #job, #aging, and #hpm (hospice and palliative medicine). Network analysis showed central hubs to be medical journals, provider organizations, individual physicians, and individual advocates. The top 150 influencers consisted primarily of physicians (49.1%), advocate/support organizations (13.8%), and media organizations (6.3%). The use of Twitter to promote geriatric medicine using #geriatrics has matured into an international digital community of interest. Future studies should examine hashtags related to age prevalent illnesses and hashtags likely to be used by patients.

scholarly journals Interactions, information and emergence: Exploring task allocation in ant colonies using network analysis

2021 ◽  
Author(s):  
Anshuman Swain ◽  
Sara D Williams ◽  
Louisa J Di Felice ◽  
Elizabeth A Hobson
Keyword(s):  
Network Analysis ◽  
Functional Groups ◽  
Task Allocation ◽  
Interaction Networks ◽  
Group Level ◽  
Ant Colonies ◽  
Individual Level ◽  
Network Measures ◽  
Interaction History ◽  
The Impact

In animal societies, individuals may take on different roles to fulfil their own needs and the needs of their groups. Ant colonies display high levels of organisational complexity, with ants fulfilling different roles at different timescales (what is known as task allocation). Factors affecting task allocation can be at the individual level (e.g., physiology), or at the group level (e.g., interaction histories). In this work, we focus on group level processes by exploring the impact of the history of interaction networks on task allocation and task switching using a previously published dataset (Mersch et al., 2013) tracking the behaviour of six Camponotus fellah colonies over 41 days. First, we investigated the architecture of interaction networks using node (individual) level network measures and their relation to the individual's task - foraging, cleaning or nursing - and whether or not the ant switched tasks. We then explored how noisy information propagation is among ants, as a function of the colony composition (how many ants are carrying out which tasks), through the information-theoretic metric of effective information. Our results show that interaction history affected task allocation, with ants more likely to switch to a task if they had interacted with other ants carrying out that task. The degree to which interaction history affected task allocation, as well as the noise in their interactions, depended on which groups of ants are interacting. Overall, we showed that colony cohesion is stable even as ant-level network measures vary more for ants when they switched functional groups; thus ant colonies maintain a high level of information flow as determined by network analysis and ant functional groups play different roles in maintaining colony cohesion.

Analysis of Impact of Smart Terminal on CDMA Network and Solution

2013 ◽  
Vol 756-759 ◽  
pp. 2846-2849
Author(s):  
Ya Liu ◽  
Zhen Xu
Keyword(s):  
Network Analysis ◽  
Network Performance ◽  
Current Situation ◽  
Mobile Internet ◽  
Data Service ◽  
Huge Data ◽  
Fixed Line ◽  
Line Network ◽  
The Impact ◽  
Signaling Traffic

This paper makes an introduction to the tendency of mobile internet replacing the fixed-line network. Analysis of the impact of Smart terminals on mobile internet is expounded. Network performance is degraded by huge data service traffic and signaling traffic. This paper also offers solution for the current situation

An ecosystem approach for studying the impact of offshore wind farms: a French case study

2018 ◽  
Vol 77 (3) ◽  
pp. 1238-1246 ◽  
Author(s):  
Jean-Philippe Pezy ◽  
Aurore Raoux ◽  
Jean-Claude Dauvin
Keyword(s):  
Network Analysis ◽  
Wind Farm ◽  
Wind Farms ◽  
Sampling Strategy ◽  
Ecosystem Approach ◽  
Offshore Wind ◽  
Ecosystem Structure ◽  
Offshore Wind Farms ◽  
Ecopath Model ◽  
The Impact

Abstract The French government is planning the construction of offshore wind farms (OWF) in the next decade (around 2900 MW). Following the European Environmental Impact Assessment Directive 85/337/EEC, several studies have been undertaken to identify the environmental conditions and ecosystem functioning at selected sites prior to OWF construction. However, these studies are generally focused on the conservation of some species and there is no holistic approach for analysing the effects arising from OWF construction and operation. The objective of this article is to promote a sampling strategy to collect data on the different ecosystem compartments of the future Dieppe-Le Tréport (DLT) wind farm site, adopting an ecosystem approach, which could be applied to other OWFs for the implementation of a trophic network analysis. For that purpose, an Ecopath model is used here to derive indices from Ecological Network Analysis (ENA) to investigate the ecosystem structure and functioning. The results show that the ecosystem is most likely detritus-based, associated with a biomass dominated by bivalves, which could act as a dead end for a classic trophic food web since their consumption by top predators is low in comparison to their biomass. The systemic approach developed for DLT OWF site should be applied for other French and European installations of Offshore Wind Farm.

Measuring the Impact of Social Media

2011 ◽  
pp. 24-36 ◽  
Author(s):  
Kimiz Dalkir
Keyword(s):  
Social Media ◽  
Social Network ◽  
Social Network Analysis ◽  
Network Analysis ◽  
Evaluation Method ◽  
Real Life ◽  
Work Processes ◽  
The Social ◽  
Post Test ◽  
The Impact

This chapter focuses on a method, social network analysis (SNA) that can be used to assess the quantity and quality of connection, communication and collaboration mediated by social tools in an organization. An organization, in the Canadian public sector, is used as a real-life case study to illustrate how SNA can be used in a pre-test/post-test evaluation design to conduct a comparative assessment of methods that can be used before, during and after the implementation of organizational change in work processes. The same evaluation method can be used to assess the impact of introducing new social media such as wikis, expertise locator systems, blogs, Twitter and so on. In other words, while traditional pre-test/post-test designs can be easily applied to social media, the social media tools themselves can be added to the assessment toolkit. Social network analysis in particular is a good candidate to analyze the connections between people and content as well as people with other people.

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