scholarly journals Expectations for the confirmation of Proxima c from a long-term radial velocity follow-up

2020 ◽  
Vol 494 (1) ◽  
pp. 1387-1394 ◽  
Author(s):  
M Damasso ◽  
F Del Sordo
Keyword(s):  
Radial Velocity ◽  
Orbital Period ◽  
Statistical Significance ◽  
Time Range ◽  
Published Data ◽  
Case Scenario ◽  
Data Set ◽  
To Come ◽  
The Impact

ABSTRACT Proxima c, a candidate second planet orbiting Proxima Centauri, was detected with the radial velocity method. The announced long orbital period (5.21$^{+0.26}_{-0.22}$ yr), and small semi-amplitude of the induced Doppler signal (1.2 ± 0.4 $\rm{\,m\,s^{-1}}$), make this detection challenging and a target worthy of a follow-up in the years to come. We intend to evaluate the impact of future data on the statistical significance of the detection through realistic simulated radial velocities to be added to the published data set, spanning up to one orbital period of Proxima c in the time range 2019–2023. We find that the detection significance of Proxima c increases depending not only on the amount of data collected, but also on the number of instruments used, and especially on the time-span covered by the observational campaign. However, on average, we do not get strong statistical evidence, and we predict that, in the best-case scenario, in the next five years the detection of Proxima c can become significant at the 4-σ level. If instead Proxima c does not exist, the detected signal may lower its significance down to 2 σ.

scholarly journals Simulating radial velocity observations of trappist-1 with SPIRou

2019 ◽  
Vol 488 (4) ◽  
pp. 5114-5126 ◽  
Author(s):  
Baptiste Klein ◽  
J-F Donati
Keyword(s):  
White Noise ◽  
Radial Velocity ◽  
Gaussian Process Regression ◽  
Data Set ◽  
Stellar Activity ◽  
Sampling Schemes ◽  
Activity Curve ◽  
To Come ◽  
The Masses

ABSTRACT We simulate a radial velocity (RV) follow-up of the TRAPPIST-1 system, a faithful representative of M dwarfs hosting transiting Earth-sized exoplanets to be observed with SPIRou in the months to come. We generate an RV curve containing the signature of the seven transiting TRAPPIST-1 planets and a realistic stellar activity curve statistically compatible with the light curve obtained with the K2 mission. We find a ±5 m s−1 stellar activity signal comparable in amplitude with the planet signal. Using various sampling schemes and white noise levels, we create time-series from which we estimate the masses of the seven planets. We find that the precision on the mass estimates is dominated by (i) the white noise level for planets c, f, and e and (ii) the stellar activity signal for planets b, d, and h. In particular, the activity signal completely outshines the RV signatures of planets d and h that remain undetected regardless of the RV curve sampling and level of white noise in the data set. We find that an RV follow-up of TRAPPIST-1 using SPIRou alone would likely result in an insufficient coverage of the rapidly evolving activity signal of the star, especially with bright-time observations only, making statistical methods such as Gaussian Process Regression hardly capable of firmly detecting planet f and accurately recovering the mass of planet g. In contrast, we show that using bi-site observations with good longitudinal complementary would allow for a more accurate filtering of the stellar activity RV signal.

scholarly journals Impact of pharmacist-conducted anticoagulation patient education and telephone follow-up on transitions of care: a randomized controlled trial

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lamis R. Karaoui ◽  
Elsy Ramia ◽  
Hanine Mansour ◽  
Nisrine Haddad ◽  
Nibal Chamoun
Keyword(s):  
Tertiary Care ◽  
Intervention Group ◽  
Bleeding Event ◽  
Transitions Of Care ◽  
Control Group ◽  
Published Data ◽  
Post Discharge ◽  
Readmission Rates ◽  
The Impact

Abstract Background There is limited published data in Lebanon evaluating the impact of supplemental education for anticoagulants use, especially DOACs, on clinical outcomes such as bleeding. The study aims to assess the impact of pharmacist-conducted anticoagulation education and follow-up on bleeding and readmission rates. Methods This study was a randomized, non-blinded interventional study conducted between August 2017 and July 2019 in a tertiary care teaching Lebanese hospital. Participants were inpatients ≥18 years discharged on an oral anticoagulant for treatment. Block randomization was used. The control group received the standard nursing counseling while the intervention group additionally received pharmacy counseling. Phone call follow-ups were done on day 3 and 30 post-discharge. Primary outcomes included readmission rates and any bleeding event at day 3 and 30 post-discharge. Secondary outcomes included documented elements of education in the medical records and reported mortality upon day 30 post-discharge. Results Two hundred patients were recruited in the study (100 patients in each study arm) with a mean age of 73.9 years. In the pharmacist-counseled group, more patients contacted their physician within 3 days (14% versus 4%; p = 0.010), received explicit elements of education (p < 0.001) and documentation in the chart was better (p < 0.05). In the standard of care group, patients were more aware of their next physician appointment date (52% versus 31%, p < 0.001). No difference in bleeding rates at day 3 and 30 post-discharge was observed between the groups. Conclusions Although pharmacist-conducted anticoagulation education did not appear to reduce bleeding or readmission rates at day 30, pharmacist education significantly increased patient communication with their providers in the early days post-discharge. Trial registration Lebanon Clinical Trial Registry LBCTR2020033424. Retrospectively registered. Date of registration: 06/03/2020.

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.

scholarly journals Children with 5′-end NF1 gene mutations are more likely to have glioma

2017 ◽  
Vol 3 (5) ◽  
pp. e192 ◽  
Author(s):  
Corina Anastasaki ◽  
Stephanie M. Morris ◽  
Feng Gao ◽  
David H. Gutmann
Keyword(s):  
Gene Mutation ◽  
Statistical Significance ◽  
Gene Mutations ◽  
Neurofibromatosis Type ◽  
Published Data ◽  
Data Sets ◽  
Nonsense Mutations ◽  
Data Set ◽  
Nf1 Gene ◽  
The Relationship

Objective:To ascertain the relationship between the germline NF1 gene mutation and glioma development in patients with neurofibromatosis type 1 (NF1).Methods:The relationship between the type and location of the germline NF1 mutation and the presence of a glioma was analyzed in 37 participants with NF1 from one institution (Washington University School of Medicine [WUSM]) with a clinical diagnosis of NF1. Odds ratios (ORs) were calculated using both unadjusted and weighted analyses of this data set in combination with 4 previously published data sets.Results:While no statistical significance was observed between the location and type of the NF1 mutation and glioma in the WUSM cohort, power calculations revealed that a sample size of 307 participants would be required to determine the predictive value of the position or type of the NF1 gene mutation. Combining our data set with 4 previously published data sets (n = 310), children with glioma were found to be more likely to harbor 5′-end gene mutations (OR = 2; p = 0.006). Moreover, while not clinically predictive due to insufficient sensitivity and specificity, this association with glioma was stronger for participants with 5′-end truncating (OR = 2.32; p = 0.005) or 5′-end nonsense (OR = 3.93; p = 0.005) mutations relative to those without glioma.Conclusions:Individuals with NF1 and glioma are more likely to harbor nonsense mutations in the 5′ end of the NF1 gene, suggesting that the NF1 mutation may be one predictive factor for glioma in this at-risk population.

461Modulation of ischemic and bleeding risk by peripheral artery disease after an acute coronary syndrome

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M Cespon Fernandez ◽  
S Raposeiras Roubin ◽  
E Abu-Assi ◽  
S Manzano-Fernandez ◽  
F Dascenzo ◽  
...  
Keyword(s):  
Acute Coronary Syndrome ◽  
Peripheral Artery Disease ◽  
Cumulative Incidence ◽  
Bleeding Risk ◽  
Peripheral Artery ◽  
Data Set ◽  
Coronary Syndrome ◽  
Artery Disease ◽  
The Impact

Abstract Introduction Peripheral artery disease (PAD) is associated with heightened ischemic and bleeding risk in patients with acute coronary syndrome (ACS). With this study from real-life patients, we try to analyze the balance between ischemic and bleeding risk during treatment with dual antiplatelet therapy (DAPT) after an ACS according to the presence or not of PAD. Methods The data analyzed in this study were obtained from the fusion of 3 clinical registries of ACS patients: BleeMACS (2004–2013), CardioCHUVI/ARRITXACA (2010–2016) and RENAMI (2013–2016). All 3 registries include consecutive patients discharged after an ACS with DAPT and undergoing PCI. The merged data set contain 26,076 patients. A propensity-matched analysis was performed to match the baseline characteristics of patients with and without PAD. The impact of prior PAD in the ischemic and bleeding risk was assessed by a competitive risk analysis, using a Fine and Gray regression model, with death being the competitive event. For ischemic risk we have considered a new acute myocardial infarction (AMI), whereas for bleeding risk we have considered major bleeding (MB) defined as bleeding requiring hospital admission. Follow-up time was censored by DAPT suspension/withdrawal. Results From the 26,076 ACS patients, 1,600 have PAD (6.1%). Patients with PAD were older, and with more cardiovascular risk factors. DAPT with prasugrel/ticagrelor was less frequently prescribed in patients with PAD in comparison with the rest of the population (8.2% vs 22.8%, p<0.001). During a mean follow-up of 12.2±4.8 months, 964 patients died (3.7%), and 640 AMI (2.5%) and 685 MB (2.6%) were reported. After propensity-score matching, we obtained two matched groups of 1,591 patients. Patients with PAD showed a significant higher risk of both AMI (sHR 2.17, 95% CI 1.51–3.10, p<0.001) and MB (sHR 1.51, 95% CI 1.07–2.12, p=0.018), in comparison with those without PAD. The cumulative incidence of AMI was 63.9 and 29.8 per 1,000 patients/year in patients with and without PAD, respectively. The cumulative incidence of MB was 55.9 and 37.6 per 1,000 patients/year in patients with and without PAD, respectively. The rate difference per 1,000 patient-years for AMI between patients with and without PAD was +34.1 (95% CI 30.1–38.1), and for MB +18.3 (16.1–20.4). The net balance between ischemic and bleeding events comparing patients with and without PAD was positive (+15.8 per 1,000 patients/year, 95% CI 9.7–22.0). Conclusions PAD was associated with higher ischemic and bleeding risk after hospital discharge for ACS treated with DAPT. However, the balance between ischemic and bleeding risk was positive for patients with PAD in comparison with patients without PAD. As summary, ACS patients with PAD had an ischemic risk greater than the bleeding risk.

Effect of cold temperature on the rate of natural attenuation of benzene, toluene, ethylbenzene, and the three isomers of xylene (BTEX)

2010 ◽  
Vol 47 (5) ◽  
pp. 516-527 ◽  
Author(s):  
Ania C. Ulrich ◽  
Kristen Tappenden ◽  
James Armstrong ◽  
Kevin W. Biggar
Keyword(s):  
Natural Attenuation ◽  
Field Conditions ◽  
Published Data ◽  
Anaerobic Conditions ◽  
Data Set ◽  
Cold Temperatures ◽  
Site Analysis ◽  
Benzene Toluene ◽  
The Impact ◽  
Hydrogeological Information

The impact of cold temperatures on natural attenuation rates is poorly understood and compounded by the lack of published data, particularly under field conditions. This paper presents a collection of data from monitoring and remediation projects completed at cold temperatures. The data set was compiled from 55 studies under anaerobic conditions (46 field and nine laboratory) from sites where groundwater temperatures are typically less than 15 °C. By normalizing the data to +5 and +10 °C, the scatter in rates for BTEX degradation in groundwater was reduced by 33% to 66%. In an attempt to address the paucity of data on natural attenuation rates under cold temperatures, this study has compiled and normalized 101 anaerobic BTEX natural attenuation rates. Eleven of the 55 studies and 43 of the 101 rates presented in this study have not been previously published. Additionally, this study has compiled, for each site, relevant contaminant and hydrogeological information that can be reviewed to choose appropriate rates for preliminary site analysis.

scholarly journals Two Year Follow-Up of Patient Reported Outcomes Following Third Generation Minimally Invasive Chevron Akin Osteotomies (MICA) in Hallux Valgus Surgery

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0005
Author(s):  
Thomas L. Lewis ◽  
Robbie Ray ◽  
David Gordon
Keyword(s):  
Minimally Invasive ◽  
Hallux Valgus ◽  
Patient Reported Outcomes ◽  
Statistical Significance ◽  
Case Series ◽  
Published Data ◽  
Third Generation ◽  
Specific Patient ◽  
Patient Reported

Category: Bunion Introduction/Purpose: The aim of this study was to explore the 2 year results of third generation (using screw fixation) Minimally Invasive Chevron and Akin osteotomies (MICA) for hallux valgus correction. There is a paucity of published data regarding the outcomes of this relatively new technique. We present the largest series in the literature, using three separate validated patient-reported outcome measures (EQ-5DL, VAS Pain and Manchester Oxford Foot Questionnaire (MOXFQ), for this time point. Methods: A single surgeon case series of patients with hallux valgus underwent primary third generation minimally invasive chevron and akin osteotomies for hallux valgus correction. Between August 2015 and January 2018, 290 MICAs were performed in 203 patients that were eligible for 2 year follow up. Baseline and 2 year post-operative patient reported outcomes were collected for 164 feet in 130 patients (124 females; 6 males). Paired t-tests were used to determine the statistical significance of the difference between pre- and post-operative scores. Results: The mean age was 56.6 (range 29.5-81.0, standard deviation (s.d.) 10.9). At two year follow up, mean MOXFQ scores improved for each domain: Pain; baseline 40.6 (range 0-100, s.d. 22.8), reduced to 11.3 (range 0-75, s.d. 16.0, p<0.001); Walking; 36.0 (range 0-100, s.d. 25.9) reduced to 8.2 (range 0-75.0, s.d. 16.0, p<0.001); Social interaction; 46.7 (range 0-100, s.d. 24.3), reduced to 7.7 (range 0-75.0, s.d. 13.9, p<0.001). Mean VAS Pain score improved from 30.4 (range 0.0-90.0, s.d. 23.6) to 9.4 (range 0.00-70.0, s.d. 15.6, p<0.001). Mean EQ-5D index score improved from 0.750 (range 0.066-1.000, s.d. 0.148) to 0.892 (range 0.410-1.000, s.d. 0.135, p<0.001). Mean EQ-5D VAS score did not significantly improve from 81.9 (range 0-100, s.d. 17.1) to 83.0 (range 0-100, s.d. 18.0, p=0.559). Conclusion: This is the largest prospective case series of short-term patient reported outcomes using a validated assessment method for hallux valgus, following third generation MICA to date. These data show that this technique is effective at improving foot and ankle specific patient reported outcomes at 2 years. This cohort is being followed over the longer term.

Does race affect outcomes in triple negative breast cancer (TNBC)?

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e17543-e17543
Author(s):  
S. Ahmed ◽  
M. M. Mirza ◽  
A. Farooq ◽  
L. Kronish ◽  
M. Jahanzeb ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Racial Differences ◽  
Statistical Significance ◽  
Menopausal Status ◽  
Cox Proportional Hazards ◽  
Rank Test ◽  
Stage At Diagnosis ◽  
Cancer Specific Survival ◽  
The Impact

e17543 Background: TNBC is associated with a worse prognosis than luminal subtypes. There is discordance among studies assessing the impact of race on outcomes of TNBC. Our objective was to assess whether African American (AA) vs. Caucasian (CA) race predicted survival outcomes for women with TNBC treated at a single institution in Memphis, TN. Secondary objectives were to examine the association of race with patient and tumor characteristics. Methods: Patients with stage I-III TNBC were identified from our breast cancer database and confirmed by review of pathology reports. Event free survival (EFS) was measured from the date of surgery to the date of first recurrence (locoregional, distant, or contralateral), death from breast cancer or last follow-up. Breast cancer specific survival (BCSS) was measured from the date of surgery to the date of death from breast cancer or last follow-up. Fisher's exact test was used for association between variables, Kaplan Meier method for survival estimates, and log rank test for survival comparison between groups (p < 0.05: significant). Cox proportional hazards models with patient, tumor and treatment variables were fitted for EFS and BCSS. Results: Of the 105 patients with TNBC, 71% were AA. There was no significant association between race and stage at diagnosis (p = 0.68). 71% of AA women were < 55 years old and 43% were pre-menopausal vs. 50% and 23% of CA women respectively. There was a trend towards association of race with age and menopausal status (p = 0.08). Ninety three percent of the patients received neo/adjuvant chemotherapy. With a median follow up of 26 months, 26% of AA vs. 20% of CA women had an event (p = 0.62). Overall 3 year EFS and BCSS estimates were 69% and 82% respectively. Racial differences in EFS and BCSS for AA vs. CA (65% vs. 80% and 78% vs. 89%, respectively) did not achieve statistical significance (log rank p = 0.22 for EFS and 0.26 for BCSS). Race was not a significant predictor of EFS or BCSS on uni-variable or multi-variable analysis. Stage at diagnosis retained significance for EFS and BCSS on uni-variable and multi-variable testing. Conclusions: Race did not affect outcomes in our cohort of TNBC patients treated similarly. The high event rate underscores the poor prognosis of TNBC and the need for more effective therapies. No significant financial relationships to disclose.

scholarly journals Amikacin Pharmacokinetics To Optimize Dosing in Neonates with Perinatal Asphyxia Treated with Hypothermia

2017 ◽  
Vol 61 (12) ◽  
Author(s):  
Sinziana Cristea ◽  
Anne Smits ◽  
Aida Kulo ◽  
Catherijne A. J. Knibbe ◽  
Mirjam van Weissenbruch ◽  
...  
Keyword(s):  
Perinatal Asphyxia ◽  
Volume Of Distribution ◽  
Stochastic Simulations ◽  
Therapeutic Drug ◽  
Published Data ◽  
Data Set ◽  
Dosing Interval ◽  
Proposed Model ◽  
Dosing Regimens ◽  
The Impact

ABSTRACT Aminoglycoside pharmacokinetics (PK) is expected to change in neonates with perinatal asphyxia treated with therapeutic hypothermia (PATH). Several amikacin dosing guidelines have been proposed for treating neonates with (suspected) septicemia; however, none provide adjustments for cases of PATH. Therefore, we aimed to quantify the differences in amikacin PK between neonates with and without PATH to propose suitable dosing recommendations. Based on amikacin therapeutic drug monitoring data collected retrospectively from neonates with PATH, combined with a published data set, we assessed the impact of PATH on amikacin PK by using population modeling. Monte Carlo and stochastic simulations were performed to establish amikacin exposures in neonates with PATH after dosing according to the current guidelines and according to proposed model-derived dosing guidelines. Amikacin clearance was decreased 40.6% in neonates with PATH, with no changes in volume of distribution. Simulations showed that increasing the dosing interval by 12 h results in a decrease in the percentage of neonates reaching toxic trough levels (>5 mg/liter), from 40 to 76% to 14 to 25%, while still reaching efficacy targets compared to the results of current dosing regimens. Based on this study, a 12-h increase in the amikacin dosing interval in neonates with PATH is proposed to correct for the reduced clearance, yielding safe and effective exposures. As amikacin is renally excreted, further studies into other renally excreted drugs may be required, as their clearance may also be impaired.

scholarly journals Among-environment heteroscedasticity and genetic autocorrelation: implications for the study of phenotypic plasticity.

Genetics ◽  
1995 ◽  
Vol 139 (4) ◽  
pp. 1815-1829
Author(s):  
P Dutilleul ◽  
C Potvin
Keyword(s):  
Phenotypic Plasticity ◽  
Variance Component ◽  
Statistical Tests ◽  
Statistical Significance ◽  
Genotype By Environment Interaction ◽  
Environment Interaction ◽  
Data Set ◽  
Genotype By Environment ◽  
Sample Covariance ◽  
The Impact

Abstract The impact of among-environment heteroscedasticity and genetic autocorrelation on the analysis of phenotypic plasticity is examined. Among-environment heteroscedasticity occurs when genotypic variances differ among environments. Genetic autocorrelation arises whenever the responses of a genotype to different environments are more or less similar than expected for observations randomly associated. In a multivariate analysis-of-variance model, three transformations of genotypic profiles (reaction norms), which apply to the residuals of the model while preserving the mean responses within environments, are derived. The transformations remove either among-environment heteroscedasticity, genetic autocorrelation or both. When both nuisances are not removed, statistical tests are corrected in a modified univariate approach using the sample covariance matrix of the genotypic profiles. Methods are illustrated on a Chlamydomonas reinhardtii data set. When heteroscedasticity was removed, the variance component associated with the genotype-by-environment interaction increased proportionally to the genotype variance component. As a result, the genetic correlation rg was altered. Genetic autocorrelation was responsible for statistical significance of the genotype-by-environment interaction and genotype main effects on raw data. When autocorrelation was removed, the ranking of genotypes according to their stability index dramatically changed. Evolutionary implications of our methods and results are discussed.

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