The Next Generation Transit Survey

2017 ◽  
Vol 14 (S339) ◽  
pp. 22-22
Author(s):  
M. Burleigh
Keyword(s):  
Radial Velocity ◽  
Mass Determination ◽  
Next Generation ◽  
M Dwarfs ◽  
Early Results ◽  
The Status

AbstractThis talk introduced and described the Next Generation Transit Survey (NGTS), which is a new ground-based transit survey operating at the ESO Paranal Observatory. NGTS has been designed to achieve better photometric precision than previous ground-based surveys; it aims to detect Neptune-sized planets around Sun-like stars, and sub-Neptunes around M dwarfs that are sufficiently bright for radial-velocity confirmation and mass determination. NGTS is also optimised for ground-based follow up of exoplanet candidates from TESS and PLATO. I presented early results from the survey, and described the status of our HARPS radial-velocity and SAAO photometric follow-ups of exoplanet candidates.

scholarly journals Future Directions for Radial-Velocity Research

1999 ◽  
Vol 170 ◽  
pp. 401-409
Author(s):  
David W. Latham
Keyword(s):  
Radial Velocity ◽  
Extrasolar Planets ◽  
Space Missions ◽  
Galactic Structure ◽  
M Dwarfs ◽  
Future Directions ◽  
The Status ◽  
The Impact

AbstractI review the status of ground-based radial-velocity searches for extrasolar planets and speculate about the new results that can be expected in this field over the coming years. Then I review the plans for astrometric space missions and speculate about the impact that these missions will have on ground-based radial-velocity work, citing the specific examples of extra-solar planet research, the mass-luminosity relation for M dwarfs and metal-poor stars, and Galactic structure and evolution.

scholarly journals The CARMENES search for exoplanets around M dwarfs

2019 ◽  
Vol 627 ◽  
pp. A49 ◽  
Author(s):  
M. Zechmeister ◽  
S. Dreizler ◽  
I. Ribas ◽  
A. Reiners ◽  
J. A. Caballero ◽  
...  
Keyword(s):  
Radial Velocity ◽  
Near Infrared ◽  
Radial Velocities ◽  
Slow Rotation ◽  
M Dwarfs ◽  
Photometric Variability ◽  
Photometric Measurements ◽  
The Masses ◽  
Rule Out

Context. Teegarden’s Star is the brightest and one of the nearest ultra-cool dwarfs in the solar neighbourhood. For its late spectral type (M7.0 V), the star shows relatively little activity and is a prime target for near-infrared radial velocity surveys such as CARMENES. Aims. As part of the CARMENES search for exoplanets around M dwarfs, we obtained more than 200 radial-velocity measurements of Teegarden’s Star and analysed them for planetary signals. Methods. We find periodic variability in the radial velocities of Teegarden’s Star. We also studied photometric measurements to rule out stellar brightness variations mimicking planetary signals. Results. We find evidence for two planet candidates, each with 1.1 M⊕ minimum mass, orbiting at periods of 4.91 and 11.4 d, respectively. No evidence for planetary transits could be found in archival and follow-up photometry. Small photometric variability is suggestive of slow rotation and old age. Conclusions. The two planets are among the lowest-mass planets discovered so far, and they are the first Earth-mass planets around an ultra-cool dwarf for which the masses have been determined using radial velocities.

scholarly journals Radial velocity follow-up of GJ1132 with HARPS

2018 ◽  
Vol 618 ◽  
pp. A142 ◽  
Author(s):  
X. Bonfils ◽  
J.-M. Almenara ◽  
R. Cloutier ◽  
A. Wünsche ◽  
N. Astudillo-Defru ◽  
...  
Keyword(s):  
Radial Velocity ◽  
A Priori ◽  
Equilibrium Temperature ◽  
Correlated Noise ◽  
Minimum Mass ◽  
Stellar Rotation ◽  
Stellar Activity ◽  
Orbital Parameters ◽  
The Status

The source GJ1132 is a nearby red dwarf known to host a transiting Earth-size planet. After its initial detection, we pursued an intense follow-up with the HARPS velocimeter. We now confirm the detection of GJ1132b with radial velocities alone. We refined its orbital parameters, and in particular, its mass (mb = 1.66 ± 0.23 M⊕), density (ρb = 6.3 ± 1.3 g cm−3), and eccentricity (eb < 0.22; 95%). We also detected at least one more planet in the system. GJ1132c is a super-Earth with period Pc = 8.93 ± 0.01 days and minimum mass mc sinic = 2.64 ± 0.44 M⊕. Receiving about 1.9 times more flux than Earth in our solar system, its equilibrium temperature is that of a temperate planet (Teq = 230−300 K for albedos A = 0.75 − 0.00), which places GJ1132c near the inner edge of the so-called habitable zone. Despite an a priori favorable orientation for the system, Spitzer observations reject most transit configurations, leaving a posterior probability <1% that GJ1132c transits. GJ1132(d) is a third signal with period Pd = 177 ± 5 days attributed to either a planet candidate with minimum mass md sin id = 8.4−2.5+1.7 M⊕ or stellar activity. Its Doppler signal is the most powerful in our HARPS time series but appears on a timescale where either the stellar rotation or a magnetic cycle are viable alternatives to the planet hypothesis. On the one hand, the period is different than that measured for the stellar rotation (~125 days), and a Bayesian statistical analysis we performed with a Markov chain Monte Carlo and Gaussian processes demonstrates that the signal is better described by a Keplerian function than by correlated noise. On the other hand, periodograms of spectral indices sensitive to stellar activity show power excess at similar periods to that of this third signal, and radial velocity shifts induced by stellar activity can also match a Keplerian function. We, therefore, prefer to leave the status of GJ1132(d) undecided.

Hybrid Endovascular Repair of Thoracoabdominal Aorta: Early Results

2014 ◽  
Vol 17 (3) ◽  
pp. 146
Author(s):  
Osman Tansel Darcin ◽  
Mehmet Kalender ◽  
Ayse Gul Kunt ◽  
Okay Guven Karaca ◽  
Ata Niyazi Ecevit ◽  
...  
Keyword(s):  
Endovascular Repair ◽  
Therapeutic Option ◽  
Complete Recovery ◽  
Aortic Aneurysms ◽  
Thoracoabdominal Aorta ◽  
Mortality And Morbidity ◽  
Early Results ◽  
The Mean ◽  
Procedural Success

<p><b>Background:</b> Thoracoabdominal aortic aneurysms (TAAA) present a significant clinical challenge, as they are complex and require invasive surgery. In an attempt to prevent considerably high mortality and morbidity in open repair, hybrid endovascular repair has been developed by many authors. In this study, we evaluated the early-term results obtained from this procedure.</p><p><b>Methods:</b> From November 2010 to February 2013, we performed thoracoabdominal hybrid aortic repair in 18 patients. The mean age was 68 years (12 men, 6 women). All of the patients had significant comorbidities. Follow-up computed tomography (CT) scans were performed at 1 week, 3 months, 6 months, and annually thereafter.</p><p><b>Results:</b> All patients were operated on in a staged procedure and stent graft deployment was achieved. Procedural success was achieved in all cases. All patients were discharged with complete recovery. No endoleaks weres detected in further CT examination.</p><p><b>Conclusion:</b> Our results suggests that hybrid debranching and endovascular repair of extensive thoracoabdominal aneurysms represents a suitable therapeutic option to reduce the morbidity and mortality of TAAA repair, particularly in those typically considered at high risk for standard repair.</p>

PERUBAHAN NILAI BUDAYA MINANGKABAU DALAM NOVEL TENGGELAMNYA KAPAL VAN DER WIJCK KARYA HAMKA DAN NOVEL BULAN SUSUT KARYA ISMET FANANY (KAJIAN PERBANDINGAN)

Jurnal KATA ◽  
2018 ◽  
Vol 2 (2) ◽  
pp. 336
Author(s):  
Yulia Pebriani
Keyword(s):  
Modern Society ◽  
Local Culture ◽  
The Novel ◽  
Next Generation ◽  
The Status ◽  
Symbolic Leadership ◽  
Cultural Shifts ◽  
Time Lead

<em>Local culture is very diverse Indonesia became an honor and challenge to maintain and inherited to the next generation. Local Indonesian culture is very proud because it has a very varied diversity and unique. As time, lead to changes in lifestyle a more modern society. As a result, people will prefer the new culture that may be considered more practical than the local culture. Views on kinship, treasures, and wander in the novel Tenggelamnya Kapal Van Der Wijck Hamka works and novels Bulan Susut works Ismet Fanany changes and cultural shifts. Kinship, treasures, and wander in the novel Sinking Ship Van Der Wijck Hamka's work is described explicitly, whereas kinship, treasures, and wander in the novel Month Losses Ismet work Fanany described implicitly. Changes in people's lives has implications for social Minangkabau culture in Minangkabau society. A leadership that is both functional mamak transformed into symbolic leadership. Mamak originally as straps tribesmen, has changed the status and intrinsic meaning.</em>

Coronary endarterectomy in coronary artery disease: Factors affecting graft patency and survival

2021 ◽  
pp. 021849232110068
Author(s):  
Simon CY Chow ◽  
Jacky YK Ho ◽  
Micky WT Kwok ◽  
Takuya Fujikawa ◽  
Kevin Lim ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Graft Patency ◽  
Complete Revascularization ◽  
Coronary Endarterectomy ◽  
Factors Affecting ◽  
Early Results ◽  
Cerebrovascular Events ◽  
Obtuse Marginal ◽  
One Year

Background Coronary endarterectomy aims to improve completeness of revascularization in patients with occluded coronary vessels. The benefits of coronary endarterectomy remain uncertain. The aim of this study was to evaluate short-term surgical outcomes and factors affecting graft patency post-coronary endarterectomy. Methods Between 2009 and 2019, 81 consecutive patients who had coronary endarterectomy done were evaluated for their perioperative and early results. A total of 36 patients with follow-up coronary studies were included in patency analysis. Mortality rates, major adverse cardiac and cerebrovascular events, and graft patency were outcomes of interest. Survival and risk factor analysis were performed with Kaplan–Meier and logistic regression analysis. Results The average age of the cohort was 61.9 ± 9.29 years. Complete revascularization rate was 95.4% post-coronary endarterectomy. The 30-day and 1-year mortality was 2.5 and 6.2%, respectively. One-year major adverse cardiac and cerebrovascular events rate was 11.1%. Periprocedural myocardial infarction rate was 7.4%. Three patients required repeat revascularization within a mean follow-up duration of 49.6 ± 36.5 months. Overall graft patency was 89.2% at 20.2 months and graft patency post-coronary endarterectomy was 85.4%. Arterial grafts showed 100% patency. Vein grafts to endarterectomized obtuse marginal branch had patency rates of 33.3%. Multiple endarterectomies were associated with worse one-year major adverse cardiac and cerebrovascular events (OR: 28.6 ± 1.16; P = 0.003). Conclusions Coronary endarterectomy facilitates completeness of revascularization and does not increase early mortality. Graft patency post-coronary endarterectomy on obtuse marginal artery was suboptimal. Judicious use of coronary endarterectomy should be practiced to balance the need of completeness of revascularization against the risk of myocardial infarction.

scholarly journals Exoplanet mass estimation for a sample of targets for the Ariel mission

2021 ◽  
Author(s):  
J. R. Barnes ◽  
C. A. Haswell
Keyword(s):  
Radial Velocity ◽  
Input Parameter ◽  
Noise Sources ◽  
Time Commitment ◽  
Low Mass ◽  
Time Required ◽  
Fixed Input ◽  
The Impact ◽  
Quadrature Sampling

AbstractAriel’s ambitious goal to survey a quarter of known exoplanets will transform our knowledge of planetary atmospheres. Masses measured directly with the radial velocity technique are essential for well determined planetary bulk properties. Radial velocity masses will provide important checks of masses derived from atmospheric fits or alternatively can be treated as a fixed input parameter to reduce possible degeneracies in atmospheric retrievals. We quantify the impact of stellar activity on planet mass recovery for the Ariel mission sample using Sun-like spot models scaled for active stars combined with other noise sources. Planets with necessarily well-determined ephemerides will be selected for characterisation with Ariel. With this prior requirement, we simulate the derived planet mass precision as a function of the number of observations for a prospective sample of Ariel targets. We find that quadrature sampling can significantly reduce the time commitment required for follow-up RVs, and is most effective when the planetary RV signature is larger than the RV noise. For a typical radial velocity instrument operating on a 4 m class telescope and achieving 1 m s−1 precision, between ~17% and ~ 37% of the time commitment is spent on the 7% of planets with mass Mp < 10 M⊕. In many low activity cases, the time required is limited by asteroseismic and photon noise. For low mass or faint systems, we can recover masses with the same precision up to ~3 times more quickly with an instrumental precision of ~10 cm s−1.

Status of Histopathology Services In Ethiopia

2020 ◽  
Vol 154 (Supplement_1) ◽  
pp. S120-S120
Author(s):  
G O Yeabyo
Keyword(s):  
Addis Ababa ◽  
Public Health Problem ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
The Status ◽  
Prevention Of Cancer ◽  
Great Public Health ◽  
Cancer Diseases

Abstract Introduction/Objective Cancer is one of a great public health problem in developing countries like Ethiopia and scarcity of histopathology laboratory is another burden for diagnosis and follow up of cancer diseases. The main purpose of this study is to evaluate the accessibility of histopathology services in Ethiopia. Methods Cross sectional study design were used to analyze the status of histopathology services in Ethiopia. Results There are 13 histopathology laboratories in the nation and a survey was conducted at these institutions. Out of these 13 Histopathology services seven are located in the capital, Addis Ababa and six found out of the capital located in four different regions. About 40,239,100 habitants have no histopathology service around their catchment area. Conclusion There are very limited histopathology laboratories, as a result diagnosis and prevention of cancer diseases are inadequate throughout the country.

Fractionated Stereotactic Radiotherapy for Pituitary Adenomas

Neurosurgery ◽  
2015 ◽  
Vol 79 (3) ◽  
pp. 406-417 ◽  
Author(s):  
Sean M. Barber ◽  
Bin S. Teh ◽  
David S. Baskin
Keyword(s):  
Stereotactic Radiotherapy ◽  
Pituitary Adenomas ◽  
Progression Free Survival ◽  
Hormonal Control ◽  
Fractionated Stereotactic Radiotherapy ◽  
Small Series ◽  
Early Results ◽  
Nonfunctional Pituitary Adenomas

Abstract BACKGROUND Early results of postoperative fractionated stereotactic radiotherapy (FSRT) for functional and nonfunctional pituitary adenomas appear promising, but the majority of available evidence draws from small series with insufficient follow-up data to draw meaningful conclusions. OBJECTIVE To evaluate the long-term outcomes of a large series of patients undergoing FSRT for both functional and nonfunctional pituitary adenomas with the Novalis system (Brain LAB, Heimstetten, Germany). METHODS Chart data for 75 consecutive patients undergoing FSRT for a pituitary tumor (21 functional and 54 nonfunctional adenomas) at our institution between January 2004 and June 2013 were reviewed. RESULTS Radiographic progression-free survival was 100% over a mean of 47.8 months of radiographic follow-up (range, 12.0-131.2 months). Hormonal normalization was seen in 69.2% of patients with functional adenomas after FSRT, whereas 30.8% experienced partial hormonal control. Mild, grade I acute adverse effects were observed during radiotherapy treatment in 36 patients (48%), and objective, persistent worsening of vision occurred in a single patient (1.5%) after FSRT. New hormonal deficits were seen in 28.0% of patients after FSRT. Radiographic responses were inversely related to tumor volume. CONCLUSION FSRT delivers radiographic and functional outcomes similar to those seen with stereotactic radiosurgery and conventional radiotherapy with less resultant toxicity. FSRT is most beneficial for smaller tumors (those &lt;3 cm in diameter).

scholarly journals Early Clinical and Radiographic Outcomes of Trabecular Metal Total Ankle Using Transfibular Approach

2017 ◽  
Vol 2 (3) ◽  
pp. 2473011417S0001 ◽  
Author(s):  
Alexej Barg ◽  
Charles Saltzman
Keyword(s):  
Range Of Motion ◽  
Weight Bearing ◽  
Total Ankle Replacement ◽  
Trabecular Metal ◽  
Non Union ◽  
Early Loosening ◽  
Early Results ◽  
Ankle Replacement ◽  
Patient Reported

Category: Ankle, Ankle Arthritis Introduction/Purpose: In the last two decades, total ankle replacement (TAR) has gained more acceptance as a treatment option in patients with end-stage ankle osteoarthritis. However, there is a lack of literature on TAR using a lateral transfibular approach. Therefore, we sought to report early clinical and radiographic results of a patient cohort treated with TAR using a lateral transfibular approach by a single surgeon. Methods: Fifty-five primary total ankle arthroplasties using the Zimmer trabecular metal implant were performed in 54 patients (29 men and 25 women; mean age, 67.0 years) from October 2012 to December 2014. Clinical assessment including pain evaluation and measurement of ankle range of motion was done preoperatively and at the latest follow-up. Weight-bearing radiographs were used to determine the angular alignment of the tibial and talar components and to analyze the bone-implant interface. Intraoperative and postoperative complications, revision surgeries, and failures were evaluated. Results: Implant survival was 93% at 36 months follow-up. There were 3 revisions of a tibial component due to aseptic loosening. In 10 of 55 procedures, a secondary procedure was performed during follow-up. Mean follow-up duration was 26.6 ± 4.2 months. No delayed union or non-union was observed for fibula healing. The average VAS pain score decreased significantly from 7.9 ± 1.3 to 0.8 ± 1.2. The average total range of motion increased significantly from 22.9° ± 11.8° to 40.2° ± 11.8°. Conclusion: Early results of Zimmer trabecular metal total ankle replacement demonstrated improved patient-reported outcomes and increased ankle motion at a minimum follow-up of one year. In the first 55 consecutive cases, the fibular osteotomy required for access to the ankle healed without complications. Painful early loosening requiring revision due to lack of bony ingrowth was seen in 3 of 55 cases.

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