scholarly journals Radio Induced X-Ray Emission in Radio Quasars

1986 ◽  
Vol 119 ◽  
pp. 239-246
Author(s):  
Ajit Kembhavi
Keyword(s):  
Radio Emission ◽  
Low Energy ◽  
Current Status ◽  
X Ray ◽  
Early Results ◽  
The Relationship

The relationship between low energy X-ray emission and radio emission in radio quasars is considered. A survey of early results is presented and the current status summarized. Some remarks are made on the simultaneous correlation of X-ray emission with optical and radio emission.

scholarly journals Beyond History: The List of The Most Well Studied Human Protein Structures

2020 ◽  
Author(s):  
Zhenlu Li ◽  
Matthias Buck
Keyword(s):  
Protein Structures ◽  
Protein Sequences ◽  
Human Protein ◽  
Current Status ◽  
Protein Database ◽  
X Ray ◽  
X Ray Crystallography ◽  
Protein Biophysics ◽  
The Relationship ◽  
Past Trend

Of 20,000 or so canonical human protein sequences, as of July 2020, 6,747 proteins have had their full or partial medium to high-resolution structures determined by x-ray crystallography or other methods. Which of these proteins dominate the protein database (the PDB) and why? In this paper, we list the 272 top protein structures based on the number of their PDB depositions. This set of proteins accounts for more than 40% of all available human PDB entries and represent past trend and current status for protein science. We briefly discuss the relationship which some of the prominent protein structures have with protein biophysics research and mention their relevance to human diseases. The information may inspire researchers who are new to protein science, but it also provides a year 2020 snap-shot for the state of protein science.

scholarly journals Stellar Magnetic Dynamos and Activity Cycles

2013 ◽  
Vol 9 (S302) ◽  
pp. 190-193
Author(s):  
Nicholas J. Wright
Keyword(s):  
Coronal Emission ◽  
X Ray ◽  
Rotation Periods ◽  
Early Results ◽  
Uniform Sample ◽  
Activity Cycles ◽  
Blind Search ◽  
The Relationship ◽  
Interface Type ◽  
Stellar Dynamo

AbstractUsing a new uniform sample of 824 solar and late-type stars with measured X-ray luminosities and rotation periods we have studied the relationship between rotation and stellar activity that is believed to be a probe of the underlying stellar dynamo. Using an unbiased subset of the sample we calculate the power law slope of the unsaturated regime of the activity – rotation relationship as LX / Lbol ∝ Roβ, where β = − 2.70 ± 0.13. This is inconsistent with the canonical β = − 2 slope to a confidence of 5σ and argues for an interface-type dynamo. We map out three regimes of coronal emission as a function of stellar mass and age, using the empirical saturation threshold and theoretical super-saturation thresholds. We find that the empirical saturation timescale is well correlated with the time at which stars transition from the rapidly rotating convective sequence to the slowly rotating interface sequence in stellar spin-down models. This may be hinting at fundamental changes in the underlying stellar dynamo or internal structure. We also present the first discovery of an X-ray unsaturated, fully convective M star, which may be hinting at an underlying rotation - activity relationship in fully convective stars hitherto not observed. Finally we present early results from a blind search for stellar X-ray cycles that can place valuable constraints on the underlying ubiquity of solar-like activity cycles.

scholarly journals Stellar X-Ray Sources

1974 ◽  
Vol 60 ◽  
pp. 383-399
Author(s):  
Harvey D. Tananbaum
Keyword(s):  
Black Hole ◽  
Radio Emission ◽  
Optical Emission ◽  
Close Correlation ◽  
X Ray ◽  
Radio Outburst ◽  
The Relationship ◽  
Optical Behavior

Data are presented for Cygnus X-1, Cygnus X-3, and Scorpius X-1 from radio to X-ray wavelengths. The evidence for Cygnus X-1's being a black hole is now quite convincing. New data for Cygnus X-3 show the presence of X-ray activity at the time of the giant radio outburst. The data for Scorpius X-1 show a close correlation between the X-ray and optical behavior, but coverage was not sufficiently complete to fully assess the relationship (if any) between the X-ray and optical emission and the radio emission.

scholarly journals BAT AGN spectroscopic survey - XV: the high frequency radio cores of ultra-hard X-ray selected AGN

2020 ◽  
Vol 492 (3) ◽  
pp. 4216-4234 ◽  
Author(s):  
Krista Lynne Smith ◽  
Richard F Mushotzky ◽  
Michael Koss ◽  
Benny Trakhtenbrot ◽  
Claudio Ricci ◽  
...  
Keyword(s):  
Black Hole ◽  
Star Formation ◽  
Radio Emission ◽  
High Frequency ◽  
Physical Parameters ◽  
X Ray ◽  
Radio Imaging ◽  
Significant Difference ◽  
The Relationship ◽  
Radio Power

ABSTRACT We have conducted 22 GHz radio imaging at 1 arcsec resolution of 100 low-redshift AGN selected at 14–195 keV by the Swift-BAT. We find a radio core detection fraction of 96 per cent, much higher than lower frequency radio surveys. Of the 96 radio-detected AGN, 55 have compact morphologies, 30 have morphologies consistent with nuclear star formation, and 11 have sub-kpc to kpc-scale jets. We find that the total radio power does not distinguish between nuclear star formation and jets as the origin of the radio emission. For 87 objects, we use optical spectroscopy to test whether AGN physical parameters are distinct between radio morphological types. We find that X-ray luminosities tend to be higher if the 22 GHz morphology is jet-like, but find no significant difference in other physical parameters. We find that the relationship between the X-ray and core radio luminosities is consistent with the LR/LX ∼ 10−5 of coronally active stars. We further find that the canonical fundamental planes of black hole activity systematically overpredict our radio luminosities, particularly for objects with star formation morphologies.

scholarly journals Two Radio Pulsars with Magnetar Fields

2004 ◽  
Vol 218 ◽  
pp. 255-256 ◽  
Author(s):  
M. A. McLaughlin ◽  
D. R. Lorimer ◽  
A. G. Lyne ◽  
M. Kramer ◽  
A. J. Faulkner ◽  
...  
Keyword(s):  
Magnetic Fields ◽  
Radio Emission ◽  
Neutron Stars ◽  
Critical Field ◽  
Radio Pulsars ◽  
Pulsar Emission ◽  
X Ray ◽  
New Challenges ◽  
Surface Dipole ◽  
The Relationship

PSRs J1847–0130 and J1718–37184 have inferred surface dipole magnetic fields greater than those of any other known pulsars and well above the “quantum critical field” above which some models predict radio emission should not occur. These fields are similar to those of the anomalous X-ray pulsars (AXPs), which growing evidence suggests are “magnetars”. The lack of AXP-like X-ray emission from these radio pulsars (and the non-detection of radio emission from the AXPs) creates new challenges for understanding pulsar emission physics and the relationship between these classes of apparently young neutron stars.

Current Status of Solid-State X-Ray Systems

1985 ◽  
Vol 43 ◽  
pp. 158-161
Author(s):  
Martin Peckerar ◽  
Anastasios Tousimis
Keyword(s):  
Solid State ◽  
Electric Fields ◽  
Spectral Lines ◽  
Current Status ◽  
Mobile Charge ◽  
Electron Hole ◽  
X Ray ◽  
Sensing Systems ◽  
Transmission Electron ◽  
Electron Microscopes

Solid state x-ray sensing systems have been used for many years in conjunction with scanning and transmission electron microscopes. Such systems conveniently provide users with elemental area maps and quantitative chemical analyses of samples. Improvements on these tools are currently sought in the following areas: sensitivity at longer and shorter x-ray wavelengths and minimization of noise-broadening of spectral lines. In this paper, we review basic limitations and recent advances in each of these areas. Throughout the review, we emphasize the systems nature of the problem. That is. limitations exist not only in the sensor elements but also in the preamplifier/amplifier chain and in the interfaces between these components.Solid state x-ray sensors usually function by way of incident photons creating electron-hole pairs in semiconductor material. This radiation-produced mobile charge is swept into external circuitry by electric fields in the semiconductor bulk.

Hubungan antara Luas Lesi pada Foto Toraks Penderita TB Paru Dewasa yang Memiliki Riwayat Diabetes Melitus dengan Indeks Massa Tubuh di Rumah Sakit Hasan Sadikin Bandung

2016 ◽  
Vol 1 (3) ◽  
pp. 138-144
Author(s):  
Ina Edwina ◽  
Rista D Soetikno ◽  
Irma H Hikmat
Keyword(s):  
Chest Radiograph ◽  
Chi Square ◽  
Pulmonary Tb ◽  
X Ray ◽  
Consecutive Sampling ◽  
Close Relationship ◽  
Chi Square Test ◽  
Chest X Ray ◽  
The Relationship ◽  
Diabetes Melitus

Background: Tuberculosis (TB) and diabetes mellitus (DM) prevalence rates are increasing rapidly, especially in developing countries like Indonesia. There is a relationship between TB and DM that are very prominent, which is the prevalence of pulmonary TB with DM increased by 20 times compared with pulmonary TB without diabetes. Chest X-ray picture of TB patients with DM is atypical lesion. However, there are contradictories of pulmonary TB lesion on chest radiograph of DM patients. Nutritional status has a close relationship with the morbidity of DM, as well as TB.Objectives: The purpose of this study was to determine the relationship between the lesions of TB on the chest radiograph of patients who su?er from DM with their Body Mass Index (BMI) in Hasan Sadikin Hospital Bandung.Material and Methods: The study was conducted in Department of Radiology RSHS Bandung between October 2014 - February 2015. We did a consecutive sampling of chest radiograph and IMT of DM patients with clinical diagnosis of TB, then the data was analysed by Chi Square test to determine the relationship between degree of lesions on chest radiograph of pulmonary TB on patients who have DM with their BMI.Results: The results showed that adult patients with active pulmonary TB with DM mostly in the range of age 51-70 years old, equal to 62.22%, with the highest gender in men, equal to 60%. Chest radiograph of TB in patients with DM are mostly seen in people who are obese, which is 40% and the vast majority of lesions are minimal lesions that is equal to 40%.Conclusions: There is a signifcant association between pulmonary TB lesion degree with BMI, with p = 0.03

COVID-19 in children: Pathogenesis and current status

2020 ◽  
Author(s):  
Lawrence Frenkel ◽  
Fernando Gomez ◽  
Joseph A Bellanti
Keyword(s):  
Respiratory Disease ◽  
Respiratory Symptoms ◽  
Distress Syndrome ◽  
Clinical Course ◽  
Current Status ◽  
Current Evidence ◽  
Initial Description ◽  
Relationship Of ◽  
Inflammatory Syndrome ◽  
The Relationship

Background: Since its initial description in December 2019 in Wuhan, China, coronavirus disease 2019 (COVID-19) has rapidly progressed into a worldwide pandemic, which has affected millions of lives. Unlike the disease in adults, the vast majority of children with COVID-19 have mild symptoms and are largely spared from severe respiratory disease. However, thereare children who have significant respiratory disease, and some may develop a hyperinflammatory response similar to thatseen in adults with COVID-19 and in children with Kawasaki disease (KD), which has been termed multisystem inflammatory syndrome in children (MIS-C).Objective: The purpose of this report was to examine the current evidence that supports the etiopathogenesis of COVID-19 in children and the relationship of COVID-19 with KD and MIS-C as a basis for a better understanding of the clinical course, diagnosis, and management of these clinically perplexing conditions.Results: The pathogenesis of COVID-19 is carried out in two distinct but overlapping phases of COVID-19: the first triggered by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) itself and the second by the host immune response. Children with KD have fewer of the previously described COVID-19–associated KD features with less prominent acute respiratory distress syndrome and shock than children with MIS-C.Conclusion: COVID-19 in adults usually includes severe respiratory symptoms and pathology, with a high mortality. Ithas become apparent that children are infected as easily as adults but are more often asymptomatic and have milder diseasebecause of their immature immune systems. Although children are largely spared from severe respiratory disease, they canpresent with a SARS-CoV-2–associated MIS-C similar to KD.

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