On the role of collisions with meteoroids in splitting and acceleration of heliocentric velocity of comets

2020 ◽  
Vol 29 (1) ◽  
pp. 47-50
Author(s):  
Ayyub Guliyev ◽  
Rustam Guliyev
Keyword(s):  
Meteoroid Streams ◽  
Long Period ◽  
Comet Nuclei ◽  
Heliocentric Velocity

AbstractThe hypothesis on the role of the meteoroid impacts in the comet nuclei splitting as well as acceleration of their heliocentric velocity are considered. Inclinations of the orbits of split comets relative to the movement planes of 100 known meteoroid streams are calculated. The analysis is carried out for the cases: when the cometary nodes are located from the meteoroids orbit < 0.1 AU; MOID-values less than 0.1 AU. In the case of split long-period comets irregularity (maximum near 180°) of the distribution of the inclinations has been found. Comets, constituting this maximum, could have head-on collisions with meteoroids. A similar analysis is carried out relatively to the hyperbolic comets (HCs). Analysis is based on the assumption that the acceleration of the heliocentric velocities of the comet also is caused by collisions with meteoroids. The inclinations of the orbits of 300 HCs relative to 100 known meteoroid streams have the significant maxima in the interval of 90°− 101.5°. Acceleration of comet velocity might be the result of “slanting” collisions with meteoroids.

Facilitators, challenges and usefulness of an asthma educational programme

2020 ◽  
pp. 001789692098162
Author(s):  
Muhammad Naeem ◽  
Hamad Ghalib Dailah
Keyword(s):  
Cultural Context ◽  
Educational Programme ◽  
Structured Interviews ◽  
Policy Makers ◽  
Long Period ◽  
Breathing Techniques ◽  
Educational Programmes ◽  
Asthma Patients ◽  
Programme Content

Background: This study explored the role of hospitals, specialised doctors and staff in developing patient awareness, participation and motivation concerning asthma control. It also looked at the challenges that undermine the value of asthma educational programmes, especially in an Arab cultural context. Methods: Semi-structured interviews were used to collect data from 30 asthma patients who had been living with asthma for a long period of time. Results: Findings highlight how an asthma educational programme can increase patient knowledge about the causes of asthma. Following the programme, patients had a better understanding of levels of medication, breathing techniques and rest and relaxation. Awareness of support from health professionals for managing depression and frustration also increased. However, some patients felt that the asthma educational programme content and delivery was not very interactive and was too lengthy. Conclusion: Findings can help policy makers, researchers, hospitals, doctors and the national Ministry of Health improve the content of future asthma educational programmes. They can also inform the development of a research framework to extend understanding of relevant issues in an Arabian context.

Document supply and resource sharing in Portuguese libraries: the role of the National Library

2010 ◽  
Vol 38 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Elisa Maria Gaudêncio Soares
Keyword(s):  
Information Technology ◽  
Resource Sharing ◽  
Design Methodology ◽  
Public Library ◽  
Supply System ◽  
National Library ◽  
Content Type ◽  
Long Period ◽  
Recent Developments

PurposeThe purpose of the paper is to describe the development of the Portuguese document supply system with particular emphasis on the role of the National Library but also in its academic and public library sectors.Design/methodology/approachThe paper is descriptive in nature.FindingsPortugal emerged from a long period of monarchy and dictatorship, profited from being a EU member, and libraries are now exploiting the advantages of information technology particularly for the benefit of remote users.Originality/valueThis is probably the first overview of historical and recent developments in document supply in Portugal.

scholarly journals An Abbey as a Stronghold

2021 ◽  
Vol 17 (1) ◽  
pp. 229-271
Author(s):  
Hrvoje Kekez
Keyword(s):  
Virgin Mary ◽  
16Th Century ◽  
Defense System ◽  
Long Period ◽  
Blessed Virgin Mary ◽  
Strategic Role ◽  
Large Estate ◽  
Do So

The main goal of this paper is to analyze the strategic role of Cistercian abbey of Blessed Virgin Mary in Topusko (medieval Toplica) in anti-Ottoman defense during 16th century, especially because it is rather exceptional of usage sacral complex in anti-Ottoman defense system in rather long period. In order to do so it is determined and analyzed strategic importance of the monastic complex in anti-Ottoman defense line and the change of it according to ever going Ottoman conquest of new territories, i.e. approaching of the bordering line. Furthermore, the organization of defense of the rather large estate of Topusko abbey as well as the changes of the monastic fortifications are addressed. Even more, the role of the commendatory abbots of the abbey, as well the serves of the abbey, in the larger efforts in composing and functioning of the anti-Ottoman defense line are analyzed. Finally, the proximate time and context of the final abandoning of the former Cistercian abbey is determined.

scholarly journals Armenian Women In Jordan

1970 ◽  
pp. 24-26
Author(s):  
Arda Dargarabedian
Keyword(s):  
Ethnic Minorities ◽  
Economic Status ◽  
Long Period ◽  
Armenian Women

Armenians are among the smallest ethnic minorities in Jordan and have been in the country for a fairly long period of time. This paper will deal mainly with the position and role of Armenian women in Jordanian society by reviewing their general characteristics, social and economic status (based on data from a recent study about Armenians in Jordan), using indicators that reflect their position and role in the concerned areas from a gendered perspective.

Southeast Europe

2021 ◽  
pp. 712-729
Author(s):  
Vasilios N. Makrides
Keyword(s):  
Roman Catholicism ◽  
Southeast Europe ◽  
Religious Identities ◽  
Orthodox Christian ◽  
The Balkans ◽  
Long Period ◽  
Modernization Process ◽  
Religious Landscape ◽  
Geographical Context

This chapter charts the religious landscape of Southeast Europe and considers its religious specificities in their historical and geographical context. To this purpose, it discusses the significance of the Orthodox Christian heritage of Byzantium; the cleavage between Eastern and Western Christianity (both Roman Catholicism and Protestantism) and inter-confessional dynamics; the presence of Islam and the long period of Ottoman rule; the existence of other religions in the region; the role of Russia in Southeast European affairs; ethno-religious identities and the rise of nationalism; the communist and the post-communist periods; and finally, the negative discourse about the Balkans in the context of Southeast European distinctiveness, the modernization process, and the potential for religion in this.

scholarly journals The Role of Long Period Stacking Ordered Phase in Dynamic Recrystallization of a Mg–Gd–Y–Zn–Zr Alloy during Multi-Directional Forging Process

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3290
Author(s):  
Huiling Liu ◽  
Yingze Meng ◽  
Huisheng Yu ◽  
Wenlong Xu ◽  
Siyang Zhang ◽  
...  
Keyword(s):  
Dynamic Recrystallization ◽  
Nucleation Site ◽  
Nucleation Mechanism ◽  
Forging Process ◽  
Lpso Phase ◽  
Long Period ◽  
Texture Intensity ◽  
Uniform Microstructure ◽  
Zr Alloy

The Mg–Gd–Y–Zn–Zr alloy containing a long period stacking ordered (LPSO) phase was subjected to multi-pass deformation by means of a multi-directional forging process, and the microstructure evolution and the influence of the LPSO phase on its dynamic recrystallization (DRX) were studied. The results showed that multi-directional forging can effectively refine the grain with the DRX fraction increased, and DRXed grains lead to the decrease of the texture intensity, which can significantly improve the mechanical properties of the alloy. The different morphologies of the LPSO phase have different degrees of promotion relative to DRX behavior. The lamellar LPSO phase with kinks promoted dislocation plugging, where there could be a potential nucleation site for DRX grains. The fragmented lamellar LPSO phase promoted the DRX process through the particle-stimulated nucleation mechanism, and the block-shaped phase was more prone to stress concentration, which promoted DRX. These effects resulted in continuous grain refinement and a more uniform microstructure.

scholarly journals Non-gravitational effects change the original 1/a-distribution of near-parabolic comets

2020 ◽  
Vol 633 ◽  
pp. A80 ◽  
Author(s):  
Małgorzata Królikowska
Keyword(s):  
Semimajor Axis ◽  
Oort Cloud ◽  
Gravitational Acceleration ◽  
Gravitational Effects ◽  
Long Period ◽  
Dynamical Properties ◽  
The Individual ◽  
Almost All ◽  
Data Processing Methods

Context. The original 1∕a-distribution is the only observational basis for the origin of long-period comets (LPCs) and the dynamical properties of the Oort Cloud. Although they are very subtle in the motion of these comets, non-gravitational effects can cause major changes in the original semimajor axis, 1∕aori. Aims. We obtained reliable non-gravitational orbits for as many LPCs with small perihelion distances of q < 3.1 au as possible, and determined the corresponding shape of the Oort spike. Methods. We determined the osculating orbits of each comet using several data-processing methods, and selected the preferred orbit using a few specific criteria. The distribution of 1∕aori for the whole comet sample was constructed using the individual Gaussian distribution we obtained for the preferred solution of each comet. Results. The derived distribution of 1∕aori for almost all known small-perihelion Oort spike comets was based on 64% of the non-gravitational orbits. This was compared with the distribution based on purely gravitational orbits, as well as with 1∕aori constructed earlier for LPCs with q > 3.1 au. We present a statistical analysis of the magnitudes of the non-gravitational acceleration for about 100 LPCs. Conclusions. The 1∕aori-distribution, which is based mainly on the non-gravitational orbits of small-perihelion Oort spike comets, is shifted by about 10 × 10−6 au−1 to higher values of 1∕aori compared with the distribution that is obtained when the non-gravitational effects on comet motion are ignored. We show the differences in the 1∕aori-distributions between LPCs with q < 3.1 au and those with q > 3.1 au. These findings indicate the important role of non-gravitational acceleration in the motion and origin of LPCs and in the formation of the Oort Cloud.

Unilateral Adrenalectomy for Primary Bilateral Macronodular Adrenal Hyperplasia: Analysis of 71 Cases

2019 ◽  
Vol 128 (12) ◽  
pp. 827-834
Author(s):  
Mohammad Sheikh-Ahmad ◽  
Gabriel Dickstein ◽  
Ibrahim Matter ◽  
Carmela Shechner ◽  
Jacob Bejar ◽  
...  
Keyword(s):  
Medical Center ◽  
Urinary Free Cortisol ◽  
Adrenal Hyperplasia ◽  
Unilateral Adrenalectomy ◽  
Long Period ◽  
Pubmed Database ◽  
Free Cortisol ◽  
Adrenal Masses ◽  
Current Article

Abstract Objective Primary bilateral macronodular adrenal hyperplasia (PBMAH) is characterized by benign bilateral enlarged adrenal masses, causing Cushing’s syndrome (CS). The aim of the current article is to define the role of unilateral adrenalectomy (UA) in treating patients with CS related to PBMAH. Methods A PubMed database search was conducted to identify articles reporting UA to treat PBMAH. We also report cases of PBMAH from our medical center treated by UA. Results A total number of 71 cases of PBMAH (62 cases reported in the literature and 9 cases from our center) are presented. Most patients were women (73.2%) and most UA involved the left side (64.3%). In most cases, the resected gland was the larger one. Following UA, 94.4% of cases had remission of hypercortisolism. Recurrence rate of CS was 19.4% and hypoadrenalism occurred in 29.6%. After UA, when the size of the remained adrenal gland was equal or greater than 3.5 cm, CS persisted in 21.4% of cases, and recurrence occurred in 27.3% of cases (after 20±9.2 months). However, when the size of the remained gland was less than 3.5 cm, CS resolved in all cases and recurrence occurred in 21.2% of cases after a long period (65.6±52.1 months). High levels of urinary free cortisol (UFC) were not correlated with post-surgical CS recurrence or persistence. Conclusions UA leads to beneficial outcomes in patients with CS related to PBMAH, also in cases with pre-surgical elevated UFC or contralateral large gland.

scholarly journals Characterization of Anaerobic Biofilms Growing on Carbon Felt Bioanodes Exposed to Air

Catalysts ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1341
Author(s):  
Raúl M. Alonso ◽  
Guillermo Pelaz ◽  
María Isabel San-Martín ◽  
Antonio Morán ◽  
Adrián Escapa
Keyword(s):  
Normal Operation ◽  
Carbon Felt ◽  
Dissolved Oxygen Concentration ◽  
Oxygen Penetration ◽  
Long Period ◽  
And Performance ◽  
Catalytic Capacity ◽  
Felt Electrodes

The role of oxygen in anodic biofilms is still a matter of debate. In this study, we tried to elucidate the structure and performance of an electrogenic biofilm that develops on air-exposed, carbon felt electrodes, commonly used in bioelectrochemical systems. By simultaneously recording the current density produced by the bioanode and dissolved oxygen concentration, both inside and in the vicinity of the biofilm, it was possible to demonstrate the influence of a protective aerobic layer present in the biofilm (mainly formed by Pseudomonas genus bacteria) that prevents electrogenic bacteria (such as Geobacter sp.) from hazardous exposure to oxygen during its normal operation. Once this protective barrier was deactivated for a long period of time, the catalytic capacity of the biofilm was severely affected. In addition, our results highlighted the importance of the material’s porous structure for oxygen penetration in the electrode.

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