scholarly journals Eclipsing Binaries in Dynamically Interacting Close, Multiple Systems

Galaxies ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 9
Author(s):  
Tamás Borkovits
Keyword(s):  
Orbital Period ◽  
Eclipsing Binaries ◽  
Detection Methods ◽  
Stellar Systems ◽  
Short Term ◽  
Multiple Star ◽  
Multiple Systems ◽  
History Of ◽  
Dynamical Information

Close, compact, hierarchical, and multiple stellar systems, i.e., multiples having an outer orbital period from months to a few years, comprise a small but continuously growing group of the triple and multiple star zoo. Many of them consist of at least one eclipsing pair of stars and, therefore, exhibit readily observable short-term dynamical interactions among the components. Thus, their dynamical and astrophysical properties can be explored with high precision. In this paper we present an overview of the history of the search for additional components around eclipsing binaries from the first serendipitous discoveries to more systematic recent studies. We describe the different observational detection methods and discuss their connections to the different kinds of astrophysical and dynamical information that can be mined from different datasets. Moreover, the connection amongst the observable phenomena and the long-term dynamics of such systems is also discussed.

scholarly journals Rheumatoid arthritis onset after COVID-19 infection: a case report

2021 ◽  
Vol 9 (12) ◽  
pp. 3713
Author(s):  
Thafar S. A. Safar ◽  
Karmen B. Katay ◽  
Reem H. Khamis
Keyword(s):  
Rheumatoid Arthritis ◽  
Case Report ◽  
Pathological Condition ◽  
Primary Health Care Centre ◽  
Short Term ◽  
Health Care Centre ◽  
Immune Mediated ◽  
Small Hand ◽  
History Of

At the end of 2019, coronavirus disease (COVID-19) outbreak is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). Worldwide researchers and physician try to explore the mechanisms of damage induced by virus, they focus on the short-term and long-term immune-mediated consequences induced by the virus infection. Every day discover a new pathological condition induced by virus and new symptoms and disease may occur after recovery from disease. Our case report is 41 years old, Indian lady who presented to our primary health care centre complaining of multiple small hand joints pain, both elbows and knees pain with swelling of them and prolonged morning stiffness, diagnosed seropositive rheumatoid arthritis (RA) (arthritis, positive rheumatoid factor (RF), and X-ray changes) after 1 month recovery from COVID-19 infection. She did not have any joint pain and she had negative RF before COVID-19 infection with no family history of RA.

scholarly journals Journal of the History of Economic Thought Preprints - Limits to Arbitrage and Interest Rates: A Debate Between Keynes, Hawtrey and Hicks

2018 ◽  
Author(s):  
Lucy BRILLANT
Keyword(s):  
Business Cycle ◽  
Central Bank ◽  
Interest Rates ◽  
Economic Thought ◽  
History Of Economic Thought ◽  
Short Term ◽  
Limits To Arbitrage ◽  
History Of ◽  
The Business Cycle

This paper deals with a debate between Hawtrey, Hicks and Keynes concerning the capacity of the central bank to influence the short-term and the long-term rates of interest. Both Hawtrey and Keynes considered the central bank’s ability to influence short-term rates of interest. However, they do not put the same emphasis on the study of the long-term rates of interest. According to Keynes, long-term rates are influenced by future expected short-term rates (1930, 1936), whereas for Hawtrey (1932, 1937, 1938), long-term rates are more dependent on the business cycle. Short-term rates do not have much effect on long-term rates according to Hawtrey. In 1939, Hicks enters the controversy, giving credit to both Hawtrey’s and Keynes’s theories, and also introducing limits to the operations of arbitrage. He thus presented a nuanced view.

5. Long Waves and Conjunctures of Democratization

2018 ◽  
pp. 67-81
Author(s):  
Dirk Berg-Schlosser
Keyword(s):  
Eighteenth Century ◽  
Long Waves ◽  
Political Equality ◽  
Short Term ◽  
Late Eighteenth Century ◽  
Long Wave ◽  
Late Eighteenth ◽  
The Future ◽  
History Of

This chapter focuses on the history of democratization since the late eighteenth century. It introduces the concepts of ‘waves’ (trends) and ‘conjunctures’ (briefer turmoils) and delineates the major developments in this respect. In this way, the major long-term and short-term factors leading to the emergence and breakdowns of democracies are also highlighted. The first long wave occurred during the period 1776–1914, followed by the first positive conjuncture in 1918–19, the second long wave (with some intermittent turbulences) in 1945–88, and the latest conjuncture in 1989–90. The chapter identifies the main ingredients to democratization throughout history, namely: republicanism, representation, and political equality. It concludes by considering some of the current perspectives and dangers for the future of democracy.

scholarly journals petar: a high-performance N-body code for modelling massive collisional stellar systems

2020 ◽  
Vol 497 (1) ◽  
pp. 536-555 ◽  
Author(s):  
Long Wang ◽  
Masaki Iwasawa ◽  
Keigo Nitadori ◽  
Junichiro Makino
Keyword(s):  
Globular Clusters ◽  
High Performance ◽  
Computational Time ◽  
Stellar Systems ◽  
Processing Unit ◽  
Desktop Computer ◽  
Multiple Systems ◽  
Hybrid Parallelization ◽  
Good Agreement

ABSTRACT The numerical simulations of massive collisional stellar systems, such as globular clusters (GCs), are very time consuming. Until now, only a few realistic million-body simulations of GCs with a small fraction of binaries ($5{{\ \rm per\ cent}}$) have been performed by using the nbody6++gpu code. Such models took half a year computational time on a Graphic Processing Unit (GPU)-based supercomputer. In this work, we develop a new N-body code, petar, by combining the methods of Barnes–Hut tree, Hermite integrator and slow-down algorithmic regularization. The code can accurately handle an arbitrary fraction of multiple systems (e.g. binaries and triples) while keeping a high performance by using the hybrid parallelization methods with mpi, openmp, simd instructions and GPU. A few benchmarks indicate that petar and nbody6++gpu have a very good agreement on the long-term evolution of the global structure, binary orbits and escapers. On a highly configured GPU desktop computer, the performance of a million-body simulation with all stars in binaries by using petar is 11 times faster than that of nbody6++gpu. Moreover, on the Cray XC50 supercomputer, petar well scales when number of cores increase. The 10 million-body problem, which covers the region of ultracompact dwarfs and nuclear star clusters, becomes possible to be solved.

scholarly journals Systematic review of clinical outcomes after prophylactic surgery

2016 ◽  
Vol 98 (6) ◽  
pp. 353-357 ◽  
Author(s):  
CR Davis ◽  
AEJ Trevatt ◽  
A Dixit ◽  
V Datta
Keyword(s):  
Systematic Review ◽  
Acute Appendicitis ◽  
Prophylactic Surgery ◽  
Cochrane Central Register ◽  
Short Term ◽  
Asymptomatic Patients ◽  
Central Register ◽  
Life Threatening ◽  
History Of

Introduction Prophylactic appendicectomy is performed prior to military, polar and space expeditions to prevent acute appendicitis in the field. However, the risk–benefit ratio of prophylactic surgery is controversial. This study aimed to systematically review the evidence for prophylactic appendicectomy. It is supplemented by a clinical example of prophylactic surgery resulting in life-threatening complications. Methods A systematic review was performed using MEDLINE® and the Cochrane Central Register of Controlled Trials. Keyword variants of ‘prophylaxis’ and ‘appendicectomy’ were combined to identify potential papers for inclusion. Papers related to prophylactic appendicectomy risks and benefits were reviewed. Results Overall, 511 papers were identified, with 37 papers satisfying the inclusion criteria. Nine reported outcomes after incidental appendicectomy during concurrent surgical procedures. No papers focused explicitly on prophylactic appendicectomy in asymptomatic patients. The clinical example outlined acute obstruction secondary to adhesions from a prophylactic appendicectomy. Complications after elective appendicectomy versus the natural history of acute appendicitis in scenarios such as polar expeditions or covert operations suggest prophylactic appendicectomy may be appropriate prior to extreme situations. Nevertheless, the long-term risk of adhesion related complications render prophylactic appendicectomy feasible only when the short-term risk of acute appendicitis outweighs the long-term risks of surgery. Conclusions Prophylactic appendicectomy is rarely performed and not without risk. This is the first documented evidence of long-term complications following prophylactic appendicectomy. Surgery should be considered on an individual basis by balancing the risks of acute appendicitis in the field with the potential consequences of an otherwise unnecessary surgical procedure in a healthy patient.

scholarly journals Management of hydroureteronephrosis secondary to an aberrant middle rectal artery in a patient with congenital unilateral renal agenesis

2019 ◽  
Vol 12 (11) ◽  
pp. e231576
Author(s):  
Jason Jae Yeun Kim ◽  
Margaret Mary Mansbridge ◽  
Brendan Jones ◽  
Christopher Bernard Michael Tracey
Keyword(s):  
Family History ◽  
Renal Agenesis ◽  
Short Term ◽  
Retrograde Pyelography ◽  
Unilateral Renal Agenesis ◽  
Middle Rectal Artery ◽  
History Of

Presented here is the case of a 21-year-old man, with a family history of unilateral renal agenesis, who presented with obstruction of his solitary functioning right kidney. Initially thought to be secondary to an obturator fossa hernia on endoscopic and retrograde pyelography assessment, diagnosis of obstruction secondary to an aberrant middle rectal artery was determined at laparotomy and division of this vessel relieved the patient’s obstruction without any short-term or long-term complications. To the best of the authors’ knowledge, this is the first reported case in the literature of hydroureteronephrosis secondary to an aberrant middle rectal artery.

History of lobotomy in Poland

2017 ◽  
Vol 29 (1) ◽  
pp. 3-21 ◽  
Author(s):  
Kinga Jęczmińska
Keyword(s):  
Clinical Research ◽  
Clinical Evaluation ◽  
Long Term Results ◽  
Short Term ◽  
History Of

In Poland, there were 176 cases of prefrontal leucotomy performed by Moniz’s method between 1947 and 1951. There were also several cases in which alternative psychosurgical techniques were used: prefrontal topectomy by Bilikiewicz and colleagues, and prefrontal topischemia by Ziemnowicz. This article analyses the following: publications by Choróbski, who performed lobotomy in Poland, and by Korzeniowski, who assessed its short-term results; a report by Bornsztajn, who reviewed general results of the method; and clinical research by Broszkiewicz and by Konieczyńska, who assessed Polish patients in terms of long-term results of lobotomy. Negative clinical evaluation of lobotomy led to its abandonment in Poland, a decision strengthened by a regulation that forbade lobotomy in the USSR and impacted Polish psychiatry.

scholarly journals Phenotypic and treatment outcome data on SUNCT and SUNA, including a randomised placebo-controlled trial

Cephalalgia ◽  
2017 ◽  
Vol 38 (9) ◽  
pp. 1554-1563 ◽  
Author(s):  
Hsing-Yu Weng ◽  
Anna S Cohen ◽  
Christoph Schankin ◽  
Peter J Goadsby
Keyword(s):  
Controlled Trial ◽  
Clinical Manifestations ◽  
Primary Headache ◽  
Outcome Data ◽  
Short Term ◽  
Autonomic Symptoms ◽  
Primary Headache Disorders ◽  
Cranial Autonomic Symptoms ◽  
History Of

Background Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) are two rare headache syndromes classified broadly as Trigeminal Autonomic Cephalalgias (TACs). Methods Here, 65 SUNCT (37 males) and 37 SUNA (18 males) patients were studied to describe their clinical manifestations and responses to treatment. Results Pain was almost always unilateral and side-locked. There were three types of attack: Single stabs, stab groups, and a saw-tooth pattern, with some patients experiencing a mixture of two types. As to cranial autonomic symptoms, SUNA patients mainly had lacrimation (41%) and ptosis (40%). Most cases of the two syndromes had attack triggers, and the most common triggers were touching, chewing, or eating for SUNCT, and chewing/eating and touching for SUNA. More than half of each group had a personal or family history of migraine that resulted in more likely photophobia, phonophobia and persistent pain between attacks. For short-term prevention, both syndromes were highly responsive to intravenous lidocaine by infusion; for long-term prevention, lamotrigine and topiramate were effective for SUNCT, and lamotrigine and gabapentin were efficacious in preventing SUNA attacks. A randomized placebo-controlled cross-over trial of topiramate in SUNCT using an N-of-1 design demonstrated it to be an effective treatment in line with clinical experience. Conclusions SUNCT and SUNA are rare primary headache disorders that are distinct and very often tractable to medical therapy.

Research on Object Tracking Based on Graph Model in Sports Video

2018 ◽  
Vol 11 (3) ◽  
pp. 1-14
Author(s):  
Zhexiong Cui ◽  
Jun Zhang ◽  
XiaoFei Zhang ◽  
Lishu Xu
Keyword(s):  
Object Tracking ◽  
Viterbi Algorithm ◽  
Optimal Path ◽  
Graph Model ◽  
Detection Methods ◽  
Video Frame ◽  
Short Term ◽  
Candidate Regions ◽  
The Relationship

This article is about object tracking based on graph modeling. Object tracking is usually initialized by object detection methods. The fundamental hypothesis is that the object's pattern can be separated from its surrounding background sufficiently. However, for some objects, e.g., the ball in broadcast soccer videos, it is hard to extract effective features to detect the ball in a single video frame. The strategy adopted here is to identify the object's candidate regions in several consecutive frames, and then use a graph to construct the relationship between candidate regions. Finally, a Viterbi algorithm is used to extract the optimal path of the graph as the object's trajectory. This process is called short-term tracking. Then, it is used to initialize a Kalman filter to perform long-term tracking. In the process of tracking, the tracked region is verified to determine whether tracking is a failure, and short-term tracking is restarted if a failure happens.

scholarly journals The active RS CVn-type system SZ Pictoris

2019 ◽  
Vol 490 (4) ◽  
pp. 5832-5838
Author(s):  
C I Martínez ◽  
J F González ◽  
A Buccino ◽  
R Ibañez Bustos ◽  
P J D Mauas
Keyword(s):  
Orbital Period ◽  
Type System ◽  
Short Term ◽  
Cyclic Activity ◽  
Similar Time ◽  
Orbital Parameters ◽  
Secondary Star ◽  
V Band ◽  
Composite Spectra

ABSTRACT We study the short-term variability and long-term variability of the spectroscopic binary SZ Pictoris, a southern RS CVn-type system. We used mid-resolution Echelle spectra obtained at Complejo Astronómico El Leoncito spanning 18 yr, and the photometric data from the All Sky Automated Survey data base (V band) and from the Optical Robotic Observatory (BVRI bands) for similar time lapses. We separated the composite spectra into those corresponding to both components, and we were able to determine accurate orbital parameters, in particular an orbital period of 4.95 d. We also observed a photometric modulation with half the orbital period, due to the ellipticity of the stars. We also found cyclic activity with a period of ∼2030 d, both in the photometry and in the Ca ii flux of the secondary star of the system.

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