scholarly journals TOI-2109: An Ultrahot Gas Giant on a 16 hr Orbit

2021 ◽  
Vol 162 (6) ◽  
pp. 256
Author(s):  
Ian Wong ◽  
Avi Shporer ◽  
George Zhou ◽  
Daniel Kitzmann ◽  
Thaddeus D. Komacek ◽  
...  
Keyword(s):  
Rotational Velocity ◽  
Gravitational Interaction ◽  
Phase Curve ◽  
Atmospheric Escape ◽  
Orbital Decay ◽  
Promising Target ◽  
Tidally Driven ◽  
Near Future ◽  
Brightness Modulation

Abstract We report the discovery of an ultrahot Jupiter with an extremely short orbital period of 0.67247414 ± 0.00000028 days (∼16 hr). The 1.347 ± 0.047 R Jup planet, initially identified by the Transiting Exoplanet Survey Satellite (TESS) mission, orbits TOI-2109 (TIC 392476080)—a T eff ∼ 6500 K F-type star with a mass of 1.447 ± 0.077 M ☉, a radius of 1.698 ± 0.060 R ☉, and a rotational velocity of v sin i * = 81.9 ± 1.7 km s−1. The planetary nature of TOI-2109b was confirmed through radial-velocity measurements, which yielded a planet mass of 5.02 ± 0.75 M Jup. Analysis of the Doppler shadow in spectroscopic transit observations indicates a well-aligned system, with a sky-projected obliquity of λ = 1.°7 ± 1.°7. From the TESS full-orbit light curve, we measured a secondary eclipse depth of 731 ± 46 ppm, as well as phase-curve variations from the planet’s longitudinal brightness modulation and ellipsoidal distortion of the host star. Combining the TESS-band occultation measurement with a K s -band secondary eclipse depth (2012 ± 80 ppm) derived from ground-based observations, we find that the dayside emission of TOI-2109b is consistent with a brightness temperature of 3631 ± 69 K, making it the second hottest exoplanet hitherto discovered. By virtue of its extreme irradiation and strong planet–star gravitational interaction, TOI-2109b is an exceptionally promising target for intensive follow-up studies using current and near-future telescope facilities to probe for orbital decay, detect tidally driven atmospheric escape, and assess the impacts of H2 dissociation and recombination on the global heat transport.

scholarly journals Correctable biliary atresia and cholangiocarcinoma: a case report of a 63-year-old patient

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Masaki Nio ◽  
Motoshi Wada ◽  
Hideyuki Sasaki ◽  
Hiromu Tanaka ◽  
Masatoshi Hashimoto ◽  
...  
Keyword(s):  
Biliary Atresia ◽  
Liver Tumors ◽  
Malignant Tumors ◽  
Porta Hepatis ◽  
Case Presentation ◽  
Cancer Occurrence ◽  
Long Term Survivors ◽  
Near Future

Abstract Background Although cancer occurrence following surgery for biliary atresia has gradually increased, the development of cholangiocarcinoma in a native liver survivor of biliary atresia is extremely rare. Case presentation A 3-month-old female patient with the correctable type of biliary atresia underwent a cystoduodenostomy. At 16 years of age, she underwent multiple surgeries including lysis of intestinal adhesions, ileostomy, and gastrojejunostomy at another hospital. At 54 years of age, she underwent lithotomy at the porta hepatis, resection of the residual cystic bile duct with gallbladder, and hepaticojejunostomy in Roux-en-Y fashion. As she approached the age of 63, her computed tomography scan showed no liver tumors. In the following year, she developed cholangiocarcinoma at the porta hepatis and underwent chemotherapy. However, the cancer progressed, and she died before she reached the age of 64 years. Conclusions Cholangiocarcinoma is extremely rare in patients with biliary atresia. However, physicians should follow up patients with biliary atresia as closely as possible, as malignant tumors secondary to biliary atresia may increase in number in the near future because of the growing number of long-term survivors with biliary atresia.

scholarly journals Dynamic risk stratification in the follow-up of thyroid cancer: what is still to be discovered in 2017?

2017 ◽  
Vol 24 (11) ◽  
pp. R387-R402 ◽  
Author(s):  
Jolanta Krajewska ◽  
Ewa Chmielik ◽  
Barbara Jarząb
Keyword(s):  
Thyroid Cancer ◽  
Thyroid Carcinoma ◽  
Risk Stratification ◽  
Prospective Studies ◽  
Response To Treatment ◽  
Dynamic Risk ◽  
Primary Surgery ◽  
Risk Patients ◽  
Near Future

The adequate risk stratification in thyroid carcinoma is crucial to avoid on one hand the overtreatment of low-risk and on the other hand the undertreatment of high-risk patients. The question how to properly assess the risk of relapse has been discussed during recent years and resulted in a substantial change in our approach to risk stratification in differentiated thyroid cancer, proposed by the newest ATA guidelines. First initial risk stratification, based on histopathological data is carried out just after primary surgery. It should be emphasized, that a high quality of histopathological report is crucial for proper risk stratification. Next, during the follow-up, patients are restratified considering their response to treatment applied and classified to one of the following categories: excellent response, biochemical incomplete response, structural incomplete or indeterminate response. This new approach is called dynamic risk stratification as, in contrary to the previous rigid evaluation performed at diagnosis, reflects a real-time prognosis and thereby substantially influences and personalizes disease management. In this review, we raise some unresolved questions, among them the lack of prospective studies, fulfilling evidence-based criteria, necessary to validate this model of risk stratification. We also provided some data concerning the use of dynamic risk stratification in medullary thyroid cancer, not yet reflected in ATA guidelines. In conclusion, dynamic risk stratification allows for better prediction of the risk of recurrence in thyroid carcinoma, what has been demonstrated in numerous retrospective analyses. However, the validation of this approach in prospective studies seems to be our task for near future.

scholarly journals Tracheal surgery

2016 ◽  
Vol 73 (3) ◽  
Author(s):  
A. D'Andrilli ◽  
E.A. Rendina ◽  
F. Venuta
Keyword(s):  
Surgical Resection ◽  
Surgical Techniques ◽  
Treatment Modalities ◽  
Malignant Neoplasms ◽  
New Techniques ◽  
Multidisciplinary Cooperation ◽  
Post Traumatic ◽  
Post Intubation ◽  
Near Future

Surgical resection and reconstruction of the trachea can be performed both for benign and malignant diseases. The main indications for surgery include inflammatory (generally post-intubation), congenital or post-traumatic stenoses, degenerative lesions, benign or malignant neoplasms. Success can be pursued only by accurate patient selection and timing, meticulous surgical techniques, careful follow up and, when required, multidisciplinary cooperation. Although surgical resection has now become part of our surgical practice, other treatment modalities are approaching a new clinical application era, in particular tracheal transplantation and bioengineering. These new techniques will certainly offer, in the near future, improved chances to treat difficult cases.

Evaluation of cerebral visual functions in low myopic adolescents

2021 ◽  
Vol 2 (1) ◽  
pp. 37-44
Author(s):  
Yun Liu ◽  
◽  
Li Yan ◽  
Hang Chu ◽  
Dian-Peng Wu ◽  
...  
Keyword(s):  
Zero Order ◽  
Control Group ◽  
Eye Position ◽  
Visual Functions ◽  
Fixation Stability ◽  
And Gender ◽  
Near Future ◽  
Normal Adolescents ◽  
Abnormal Results

AIM: To explore whether low myopia would affect cerebral visual functions by comparing perceptual eye position (PEP), fixation stability and stereoacuity tests between low myopic and normal adolescents. METHODS: Totally 120 adolescents matched in age and gender participated in our study. Subjects were divided into three groups according to their refractive states. The cerebral visual functions tested in our study included perceptual eye position (PEP), fixation stability and stereoacuity. Stereoacuity tests involved in our study could be categorized into two parts. The first part was classical stereo tests including Titmus and synoptophore stereo test. The second part was 3D random-dot test for zero-order stereoacuity (hereinafter as zero-order test) at different viewing distances (0.8 m and 1.5 m). RESULTS: The deviation of horizontal PEP was significantly larger in non-anisometropia when compared to control group. Both horizontal and vertical PEP bias pixels were significantly larger in anisometropia group. Both non-anisometropia group and anisometropia group had more trouble in holding their fixation stable. Moreover, anisometropia group had more abnormal results than other two groups. And in zero-order test at 1.5 m, both non-anisometropia and anisometropia had more abnormal results in stereoacuity than control group. The correlation between fixation stability and near stereoacuity (Titmus and zero-order stereoacuity at 0.8 m) was weak and positive. CONCLUSION: Low myopic adolescents still have certain defects in cerebral visual functions. Examinations used in our study are useful in assessing cerebral visual functions. They could provide better follow-up evaluation and solid ground for further specific treatments in treating defects of cerebral visual functions. So far, local retinal environment has been the focus of the development in myopia. Our results suggested that researchers might pay more attention on visual cortex in studying the mechanisms of myopia in the near future.

scholarly journals Application of OCT in the Gastrointestinal Tract

2019 ◽  
Vol 9 (15) ◽  
pp. 2991 ◽  
Author(s):  
Nicholas S. Samel ◽  
Hiroshi Mashimo
Keyword(s):  
Gastrointestinal Tract ◽  
Field Evaluation ◽  
Wide Field ◽  
Gi Tract ◽  
Advanced Imaging ◽  
Future Directions ◽  
Future Therapy ◽  
Near Future ◽  
The U.S

Optical coherence tomography (OCT) is uniquely poised for advanced imaging in the gastrointestinal (GI) tract as it allows real-time, subsurface and wide-field evaluation at near-microscopic resolution, which may improve the current limitations or even obviate the need of superficial random biopsies in the surveillance of early neoplasias in the near future. OCT’s greatest impact so far in the GI tract has been in the study of the tubular esophagus owing to its accessibility, less bends and folds and allowance of balloon employment with optimal contact to aid circumferential imaging. Moreover, given the alarming rise in the incidence of Barrett’s esophagus and its progression to adenocarcinoma in the U.S., OCT has helped identify pathological features that may guide future therapy and follow-up strategy. This review will explore the current uses of OCT in the gastrointestinal tract and future directions, particularly with non-endoscopic office-based capsule OCT and the use of artificial intelligence to aid in diagnoses.

scholarly journals The Atmospheres of Extrasolar Super-Earths

2008 ◽  
Vol 4 (S253) ◽  
pp. 263-271 ◽  
Author(s):  
Eliza Miller-Ricci ◽  
Sara Seager ◽  
Dimitar Sasselov
Keyword(s):  
Parameter Space ◽  
Large Range ◽  
Theoretical Models ◽  
Radial Velocities ◽  
Atmospheric Composition ◽  
Transmission Spectra ◽  
Earth Atmosphere ◽  
Atmospheric Escape ◽  
Wide Range

AbstractExtrasolar super-Earths (1-10 M⊕) are likely to exist with a wide range of atmospheres. While a number of these planets have already been discovered through radial velocities and microlensing, it will be the discovery of the firsttransitingsuper-Earths that will open the door to a variety of follow-up observations aimed at characterizing their atmospheres. Super-Earths may fill a large range of parameter space in terms of their atmospheric composition and mass. Specifically, some of these planets may have high enough surface gravities to be able to retain large hydrogen-rich atmosphseres, while others will have lost most of their hydrogen to space over the planet's lifetime, leaving behind an atmosphere more closely resembling that of Earth or Venus. The resulting composition of the super-Earth atmosphere will therefore depend strongly on factors such as atmospheric escape history, outgassing history, and the level of stellar irradiation that it receives. Here we present theoretical models of super-Earth emission and transmission spectra for a variety of possible outcomes of super-Earth atmospheric composition ranging from hydrogen-rich to hydrogen-poor. We focus on how observations can be used to differentiate between the various scenarios and constrain atmospheric composition.

scholarly journals Grape-6

1998 ◽  
Vol 11 (2) ◽  
pp. 597-599 ◽  
Author(s):  
J. Makino
Keyword(s):  
Gravitational Interaction ◽  
Star Clusters ◽  
Semiconductor Technology ◽  
Specialized Hardware ◽  
Peak Speed

AbstractWe overview the GRAPE-6 project, a follow-up of the teraflops GRAPE-4 project. GRAPE-6 will be completed by 1999-2000 and its planned peak speed is 200 Tflops. Its architecture will be largely similar to that of GRAPE-4, which is a specialized hardware to calculate the gravitational interaction between particles. The improvement of the speed will mainly come from the advance in the silicon semiconductor technology. GRAPE-6 will enable us to directly simulate the evolution of star clusters with up to 1 million stars.

scholarly journals Field Experience of the Sequential Combustion System for the GT24/GT26 Gas Turbine Family

1998 ◽  
Author(s):  
Franz Joos ◽  
Philipp Brunner ◽  
Marcel Stalder ◽  
Stefan Tschirren
Keyword(s):  
Gas Turbine ◽  
Research Work ◽  
Basic Research ◽  
Test Facility ◽  
Test Results ◽  
Combustion System ◽  
System A ◽  
Commercial Operation ◽  
Near Future

The first units of the Sequential Combustion System gas turbine family are in commercial operation. The first gas turbine GT24 (60Hz, 165MW-class) started the commercial operation, while the first GT26 (50Hz, 265MW-class) demonstrates its performance at the GT test facility. More engines are presently in the commissioning phase or will be in the near future. These turbines are designed to offer increased output at high GT efficiency. To acheive this, the sequential combustion system, a reheat process with two combustors, has been developed. Whereas the first combustor is based on the proven EV-combustor technology, extensive research and development efforts have been carried out in developing the lean premixed self-igniting second combustor (SEV). This paper is a follow-up of the ASME paper 96-GT-315, which described the basic research work concerning the lean premixing SEV-burners with self-ignition. The present paper reports the experience gained during commissioning of the first engines. The performance of the two combustors, as well as the measured emissions, are discussed and compared with the expected values and rig test results. Finally, the potential of the sequential combustion system to reach low NOx levels is demonstrated by unveiling the results of the extensive testing program during the commissioning phase.

scholarly journals A Seven-Year Retrospective Study on the Surveillance of Hepatitis B in Laos

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Phimpha Paboriboune ◽  
Thomas Vial ◽  
François Chassagne ◽  
Philavanh Sitbounlang ◽  
Sengaloun Soundala ◽  
...  
Keyword(s):  
Public Health ◽  
Hepatitis B ◽  
Liver Enzymes ◽  
Lao Pdr ◽  
Infection Status ◽  
Serological Markers ◽  
Reverse Transcriptase Inhibitors ◽  
Near Future ◽  
Fair Access

Objective. Lao PDR is one of the most highly endemic countries for hepatitis B in Asia and the second country for liver cancer incidence. Therefore, the follow-up of infected individuals through predictive serological markers is of utmost importance to monitor the progression of the pathology and take the decision on treatment. Methods. A retrospective-descriptive cohort study was conducted on 3,857 HBV-infected patients. Information about infection status (viral load, VL), liver function (aminotransferases), and treatments was recorded. Results. M/F sex ratio was 1.77 for a median age of 37. Patients under 37 displayed higher VL than older ones and men had higher VL than women. Initial VL ranged from <50 IU/mL to 2.5 1013 IU/mL. Median aminotransferase values were 45.5 U/L for ALAT and 44 U/L for ASAT, ranging from <8 to >2,000 U/L. Men had higher aminotransferase than women. Globally 20% of patients received treatment (mainly immunostimulant and reverse-transcriptase inhibitors); 11% had high levels of VL and liver enzymes, but only 2% of them were treated. Conclusion. Public health decisions should be taken urgently to rationalise vaccination and provide fair access to early diagnosis and treatment; otherwise the burden of HBV-associated diseases will be overwhelming for Laos in the near future.

scholarly journals Visual impairment and risk of dementia in two population-based prospective cohorts: UK Biobank and EPIC-Norfolk

2021 ◽  
Author(s):  
Thomas J Littlejohns ◽  
Shabina Hayat ◽  
Robert Luben ◽  
Carol Brayne ◽  
Megan Conroy ◽  
...  
Keyword(s):  
Visual Impairment ◽  
Proportional Hazards ◽  
Population Based ◽  
Cox Proportional Hazards ◽  
Uk Biobank ◽  
Cox Proportional Hazards Models ◽  
Hazard Ratios ◽  
Promising Target ◽  
Increased Risk

Abstract Visual impairment has emerged as a potential modifiable risk factor for dementia. However, there are a lack of large studies with objective measures of vison and with more than ten years of follow-up. We investigated whether visual impairment is associated with an increased risk of incident dementia in UK Biobank and EPIC-Norfolk. In both cohorts, visual acuity was measured using a “logarithm of the minimum angle of resolution” (LogMAR) chart and categorised as no (≤0.30 LogMAR), mild (&gt;0.3 - ≤0.50 LogMAR), and moderate to severe (&gt;0.50 LogMAR) impairment. Dementia was ascertained through linkage to electronic medical records. After restricting to those aged ≥60 years, without prevalent dementia and with eye measures available, the analytic samples consisted of 62,206 UK Biobank and 7,337 EPIC-Norfolk participants, respectively. In UK Biobank and EPIC-Norfolk. respectively, 1,113 and 517 participants developed dementia over 11 and 15 years of follow-up. Using multivariable cox proportional-hazards models, the hazard ratios for mild and moderate to severe visual impairment were 1.26 (95% Confidence Interval [CI] 0.92-1.72) and 2.16 (95% CI 1.37-3.40), in UK Biobank, and 1.05 (95% CI 0.72-1.53) and 1.93 (95% CI 1.05-3.56) in EPIC-Norfolk, compared to no visual impairment. When excluding participants censored within 5 years of follow-up or with prevalent poor or fair self-reported health, the direction of the associations remained similar for moderate impairment but were not statistically significant. Our findings suggest visual impairment might be a promising target for dementia prevention, however the possibility of reverse causation cannot be excluded.

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