scholarly journals First direct identification of the barlens vertical structure in galaxy models

2021 ◽  
Vol 648 ◽  
pp. L4
Author(s):  
Iliya S. Tikhonenko ◽  
Anton A. Smirnov ◽  
Natalia Ya. Sotnikova
Keyword(s):  
Vertical Structure ◽  
Vertical Direction ◽  
Direct Identification ◽  
Flat Structure ◽  
Body Model ◽  
Thick Part ◽  
Different Types ◽  
The Galaxy ◽  
The Face ◽  
First Time

Applying spectral dynamics methods to one typical N-body model with a barlens, we dissect the modelled bar into separate components supported by completely different types of orbits. We identify at least four components: a narrow elongated bar, a boxy bar, and two components contributing to the barlens. We analyse the vertical structure of all components that make up the thick part of the bar, which has a boxy/peanut shape (B/P bulge). We show that the ‘peanut’ shape is mainly due to the orbits that assemble the boxy part of the face-on bar. We associate the X-shape with the narrow and elongated bar. The wider part of the barlens with square-like isophotes contributes to the boxy shape of the B/P bulge when we observe the galaxy edge-on. However, the part of the barlens with rounded isophotes in the face-on view is a rather flat structure in the vertical direction without any significant off-centre protrusions. Thus, for the first time, we demonstrate that the rounded face-on barlens cannot be entirely associated with the B/P bulge.

scholarly journals Face-on structure of barlenses and boxy bars: an insight from spectral dynamics

2021 ◽  
Vol 502 (4) ◽  
pp. 4689-4707 ◽  
Author(s):  
Anton A Smirnov ◽  
Iliya S Tikhonenko ◽  
Natalia Ya Sotnikova
Keyword(s):  
Spectral Analysis ◽  
Detailed Analysis ◽  
Building Block ◽  
The Other ◽  
Spectral Dynamics ◽  
Different Types ◽  
Central Regions ◽  
The Face ◽  
First Time ◽  
Matter Concentration

ABSTRACT Based on the spectral analysis of individual orbits of stars from different N-body models, we show that the face-on morphology of the so-called ‘face-on peanut’ bars (boxy bars) and barlenses is supported by different types of orbits. For ‘face-on peanut’ bars, the so-called boxy orbits come to the fore, and they are responsible for the unusual morphology of the bar in the central regions. In the models with compact bulges, the bars show a barlens morphology in their central parts. We found that the barlens supporting orbits come in two types, one of which gives a square-like shape and the other have a rosette-like shape in the frame co-rotating with the bar. Such a shape is typical for orbits around stable loop orbits in nearly axisymmetric potentials only slightly distorted by the bar. They were already known from some of the previous studies but their role in barlens shaping was barely investigated. Although quite simple, the rosette-like orbits are found to be the main building block of a barlens in our models. The detailed analysis of all bar orbits also allowed us to distinguish the x2 orbital family and isolate the structure supported by orbits trapped around this family. The x2 family is well-known, but, apparently, for the first time in N-body models we have revealed the structure it supports by means of spectral dynamics and highlight its contribution to the barlens. We found that the x2 family population increases with an increase in central matter concentration.

scholarly journals Dynamical Modeling of the Milky Way Bugle

2013 ◽  
Vol 9 (S298) ◽  
pp. 201-206 ◽  
Author(s):  
Juntai Shen
Keyword(s):  
Milky Way ◽  
Vertical Direction ◽  
Stellar Kinematics ◽  
Kinematic Data ◽  
Kinematic Constraints ◽  
Body Model ◽  
The Galaxy ◽  
Galaxy Collisions ◽  
Dynamical Instabilities ◽  
Stellar Kinematic

AbstractBulges are commonly believed to form in the dynamical violence of galaxy collisions and mergers. We model the stellar kinematics of the Bulge Radial Velocity Assay (BRAVA) and find no sign that the Milky Way contains a classical bulge formed by scrambling pre-existing disks of stars in major mergers. Rather, the bulge appears to be a bar seen somewhat end-on, as hinted from its asymmetric boxy shape. We construct a simple but realistic N-body model of the Galaxy that self-consistently develops a bar. The bar immediately buckles and thickens in the vertical direction. As seen from the Sun, the result resembles the boxy bulge of our Galaxy. We use the new kinematic constraints to show that the classical bulge contribution cannot be very significant. The model fits the BRAVA stellar kinematic data covering the whole bulge strikingly well with no need for a merger-made classical bulge. Our model contains an intriguing vertical X-shaped structure that resembles the similar structure reported recently in the Galactic bulge. The existence of the vertical X-shaped structure also suggests that the formation of the Milky Way bulge is shaped mainly by internal disk dynamical instabilities.

Probabilistic Assessment of Reliability and Risk Values by Certification Results

2020 ◽  
pp. 52-67
Author(s):  
Vladimir A. Lapin ◽  
Erken S. Aldakhov ◽  
S. D. Aldakhov ◽  
A. B. Ali
Keyword(s):  
Seismic Risk ◽  
Housing Stock ◽  
Seismic Resistance ◽  
Probabilistic Assessment ◽  
Quantitative Estimates ◽  
Different Types ◽  
Reduce Risk ◽  
First Time ◽  
Structural Solutions ◽  
Practical Recommendations

For the first time in Almaty full passport of apartment stock of multiapartment building was carried out. The structure of the housing stock was revealed with the allocation of groups of buildings according to structural solutions and assessment of their seismic resistance. Based on the results of certification, quantitative estimates of failure probability values for different types of buildings were obtained. Formulas for estimation of quantitative value of seismic risk are obtained. The number of deaths in the estimated zem-shakes was estimated. The results of the assessments will be used for practical recommendations to reduce risk and expected losses in possible earthquakes.

The Small State Challenge

2018 ◽  
Author(s):  
Jack Corbett ◽  
Wouter Veenendaal
Keyword(s):  
Comparative Politics ◽  
Institutional Design ◽  
Small States ◽  
Small State ◽  
Informal Politics ◽  
Different Types ◽  
Approach Method ◽  
Key Terms ◽  
First Time

Chapter 1 introduces the main arguments of the book; outlines the approach, method, and data; defines key terms; and provides a chapter outline. Global theories of democratization have systematically excluded small states, which make up roughly 20 per cent of countries. These cases debunk mainstream theories of why democratization succeeds or fails. This book brings small states into the comparative politics fold for the first time. It is organized thematically, with each chapter tackling one of the main theories from the democratization literature. Different types of data are examined—case studies and other documentary evidence, interviews and observation. Following an abductive approach, in addition to examining the veracity of existing theory, each chapter is also used to build an explanation of how democracy is practiced in small states. Specifically, we highlight how small state politics is shaped by personalization and informal politics, rather than formal institutional design.

scholarly journals MiRNA Expression in Neuroendocrine Neoplasms of Frequent Localizations

2021 ◽  
Vol 7 (3) ◽  
pp. 38
Author(s):  
Alexandra Korotaeva ◽  
Danzan Mansorunov ◽  
Natalya Apanovich ◽  
Anna Kuzevanova ◽  
Alexander Karpukhin
Keyword(s):  
Mirna Expression ◽  
Malignant Tumors ◽  
Neuroendocrine Neoplasms ◽  
Specific Expression ◽  
Clinical Biomarkers ◽  
Different Types ◽  
Functional Features ◽  
First Time ◽  
Potential Biomarkers

Neuroendocrine neoplasms (NEN) are infrequent malignant tumors of a neuroendocrine nature that arise in various organs. They occur most frequently in the lungs, intestines, stomach and pancreas. Molecular diagnostics and prognosis of NEN development are highly relevant. The role of clinical biomarkers can be played by microRNAs (miRNAs). This work is devoted to the analysis of data on miRNA expression in NENs. For the first time, a search for specificity or a community of their functional characteristics in different types of NEN was carried out. Their properties as biomarkers were also analyzed. To date, more than 100 miRNAs have been characterized as differentially expressed and significant for the development of NEN tumors. Only about 10% of the studied miRNAs are expressed in several types of NEN; differential expression of the remaining 90% was found only in tumors of specific localizations. A significant number of miRNAs have been identified as potential biomarkers. However, only a few miRNAs have values that characterized their quality as markers. The analysis demonstrates the predominant specific expression of miRNA in each studied type of NEN. This indicates that miRNA’s functional features are predominantly influenced by the tissue in which they are formed.

scholarly journals Second-order neutrosophic boundary-value problem

2021 ◽  
Author(s):  
Sandip Moi ◽  
Suvankar Biswas ◽  
Smita Pal(Sarkar)
Keyword(s):  
Differential Equation ◽  
Boundary Value Problem ◽  
Differential Calculus ◽  
Boundary Value ◽  
Second Order ◽  
Numerical Examples ◽  
Different Types ◽  
First Time

AbstractIn this article, some properties of neutrosophic derivative and neutrosophic numbers have been presented. This properties have been used to develop the neutrosophic differential calculus. By considering different types of first- and second-order derivatives, different kind of systems of derivatives have been developed. This is the first time where a second-order neutrosophic boundary-value problem has been introduced with different types of first- and second-order derivatives. Some numerical examples have been examined to explain different systems of neutrosophic differential equation.

scholarly journals Interactions between an Associative Amphiphilic Block Polyelectrolyte and Surfactants in Water: Effect of Charge Type on Solution Properties and Aggregation

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1729
Author(s):  
Patrizio Raffa
Keyword(s):  
Surface Tension ◽  
Self Assembly ◽  
Interaction Model ◽  
Industrial Applications ◽  
Molecular Organization ◽  
Different Types ◽  
Solution Rheology ◽  
Interesting Class ◽  
First Time

The study of interactions between polyelectrolytes (PE) and surfactants is of great interest for both fundamental and applied research. These mixtures can represent, for example, models of self-assembly and molecular organization in biological systems, but they are also relevant in industrial applications. Amphiphilic block polyelectrolytes represent an interesting class of PE, but their interactions with surfactants have not been extensively explored so far, most studies being restricted to non-associating PE. In this work, interactions between an anionic amphiphilic triblock polyelectrolyte and different types of surfactants bearing respectively negative, positive and no charge, are investigated via surface tension and solution rheology measurements for the first time. It is evidenced that the surfactants have different effects on viscosity and surface tension, depending on their charge type. Micellization of the surfactant is affected by the presence of the polymer in all cases; shear viscosity of polymer solutions decreases in presence of the same charge or nonionic surfactants, while the opposite charge surfactant causes precipitation. This study highlights the importance of the charge type, and the role of the associating hydrophobic block in the PE structure, on the solution behavior of the mixtures. Moreover, a possible interaction model is proposed, based on the obtained data.

Healthcare and Terrorism: The Lebanese Experience

2021 ◽  
pp. 1-4
Author(s):  
Nooreddine Iskandar ◽  
Tatiana Rahbany ◽  
Ali Shokor
Keyword(s):  
Public Health ◽  
Qualitative Study ◽  
Thematic Analysis ◽  
Terrorist Attacks ◽  
Analysis Method ◽  
Structured Interviews ◽  
Security Issues ◽  
The Face ◽  
The Common ◽  
First Time

Abstract Background: Due to the common instability caused by political and security issues, Lebanese hospitals have experienced acts of terrorism multiple times. The most recent Beirut Explosion even forced several hospitals to cease operations for the first time in decades—but studies show the preparedness levels for such attacks in similar countries are low. Objective: The aim of this study is to explore the experience of Lebanese hospitals with terrorist attacks. Methods: This qualitative study used semi-structured interviews with various stakeholders to assess their experience with terrorist bombings. Data was analyzed using the thematic analysis method. Results: The researchers found that Lebanese hospitals vary greatly in their structures and procedures. Those differences are a function of 3 contextual factors: location, culture, and accreditation status. Hospitals found near ‘dangerous zones’ were more likely to be aware and to have better response to such events. A severe lack of communication, unity of command, and collaboration between stakeholders has made the process fragmented. Conclusion: The researchers recommend a larger role for the Ministry of Public Health (MOPH) in this process, and the creation of a platform where Lebanese organizations can share their experiences to improve preparedness and resilience of the Lebanese healthcare system in the face of terrorism.

scholarly journals On the formation and stability of fermionic dark matter halos in a cosmological framework

2020 ◽  
Author(s):  
Carlos R Argüelles ◽  
Manuel I Díaz ◽  
Andreas Krut ◽  
Rafael Yunis
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Space Distribution ◽  
Coarse Grained ◽  
Dark Matter Halos ◽  
The Core ◽  
The Galaxy ◽  
Gravitating Systems ◽  
The Given ◽  
First Time

Abstract The formation and stability of collisionless self-gravitating systems is a long standing problem, which dates back to the work of D. Lynden-Bell on violent relaxation, and extends to the issue of virialization of dark matter (DM) halos. An important prediction of such a relaxation process is that spherical equilibrium states can be described by a Fermi-Dirac phase-space distribution, when the extremization of a coarse-grained entropy is reached. In the case of DM fermions, the most general solution develops a degenerate compact core surrounded by a diluted halo. As shown recently, the latter is able to explain the galaxy rotation curves while the DM core can mimic the central black hole. A yet open problem is whether this kind of astrophysical core-halo configurations can form at all, and if they remain stable within cosmological timescales. We assess these issues by performing a thermodynamic stability analysis in the microcanonical ensemble for solutions with given particle number at halo virialization in a cosmological framework. For the first time we demonstrate that the above core-halo DM profiles are stable (i.e. maxima of entropy) and extremely long lived. We find the existence of a critical point at the onset of instability of the core-halo solutions, where the fermion-core collapses towards a supermassive black hole. For particle masses in the keV range, the core-collapse can only occur for Mvir ≳ E9M⊙ starting at zvir ≈ 10 in the given cosmological framework. Our results prove that DM halos with a core-halo morphology are a very plausible outcome within nonlinear stages of structure formation.

scholarly journals AB0243 CONSIDERING THE COMBINATION OF TWO BIOLOGICS IN CASE OF FAILURE OF THE MONOTHERAPY IN JUVENILE ONSET RHEUMATOID ARTHRITIS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1147.1-1147
Author(s):  
A. Haddouche ◽  
K. Ait Bellabas ◽  
W. F. Hamrani ◽  
S. Sahraoui ◽  
R. Fatma ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Alternative Therapy ◽  
Biologic Therapies ◽  
Disease Modifying Antirheumatic Drugs ◽  
Antirheumatic Drugs ◽  
Juvenile Onset ◽  
Multiple Treatment ◽  
Tnf Blocker ◽  
Different Types ◽  
First Time

Background:The management of rheumatoid arthritis refractory to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) is currently well codified and includes different types of biologics and even targeted sDMARDs. A rotation of biologic therapies is recommended in order to better control the disease.Methods:We report the case of a 20-year-old patient followed in our hospital for the management of a deforming and erosive seropositive rheumatoid arthritis (FR +, ACPA +) with a juvenile onset at the age of 8 years. The diagnosis of an immunopositive polyarticular form of JIA was retained in 2010 (9 years old); the patient was treated with methotrexate (MTX) at a dose of 10 mg per week and methylprednisolone at doses varying between 4 and 10 mg per day. Following the failure of MTX, etanercept was introduced for 6 months without success, followed by tocilizumab in 2012 at a dose of 8mg/kg/month for a year, without good response. In 2014, a course of rituximab (RTX) at a dose of 2 shots of 500mg, 2 weeks apart was prescribed followed 9 months later by etanercept at a dose of 50 mg a week for 3 years then by adalimumab (40mg/ week) because of the multiple treatment failures.In 2018, the repetition of RTX at a dose of 1g, renewed 15 days later, improved the patient for only 3 months. Then, a combination of two biologics, namely RTX (2 x 1g, 15 days apart) and adalimumab 1 month later (40mg / week) was received by the patient with a good response at 3 months. The latter was maintained for 7 months even after stopping the adalimumab following confinement for COVID-19. In September 2020, flares occurred and the adalimumab (ADA) has been delivered but without success during 3 months, stopped later for a benign form of COVID-19 (15 months after RTX). In January 2021, the association RTX + ADA was given again and we hope that it will be as effective as the first prescription.Results:The clinical and biological severity of our patient’s rheumatoid arthritis led us to give a combination of two biological treatments. Indeed, we do not have other therapeutic classes to deliver to her, that encouraged us to rotate between all the available biological therapies in our country. The combination of a CD20 inhibitor (RTX) with a TNF blocker (ADA) was safe and made possible, for the first time, the achievement of clinical and biological remission during 7 months, even after stopping the TNF blocker. Greenwald et al. reported the safety of the combination of RTX + TNF inhibitors in a randomized clinical trial in 51 patients. Its efficacy, a secondary goal of the study, was suggested at 24 weeks by the percentage of ACR 20 and ACR 50 responses that was greater than in the RTX placebo group.Conclusion:The combination of RTX with a TNF blocker can be a real alternative therapy in rheumatoid arthritis with failure to a biological monotherapy.Disclosure of Interests:None declared

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