scholarly journals Relativistic Dynamical Stability Criterion of Multiplanet Systems with a Distant Companion

2021 ◽  
Vol 923 (1) ◽  
pp. 118
Author(s):  
Lingfeng Wei ◽  
Smadar Naoz ◽  
Thea Faridani ◽  
Will M. Farr
Keyword(s):  
Numerical Simulations ◽  
Parameter Space ◽  
Stability Criterion ◽  
Short Range ◽  
Averaging Method ◽  
Orbital Parameter ◽  
Long Term Stability ◽  
Analytical Stability ◽  
Analytical Criterion

Abstract Multiplanetary systems are prevalent in our Galaxy. The long-term stability of such systems may be disrupted if a distant inclined companion excites the eccentricity and inclination of the inner planets via the eccentric Kozai–Lidov mechanism. However, the star–planet and the planet–planet interactions can help stabilize the system. In this work, we extend the previous stability criterion that only considered the companion–planet and planet–planet interactions by also accounting for short-range forces or effects, specifically, relativistic precession induced by the host star. A general analytical stability criterion is developed for planetary systems with N inner planets and a relatively distant inclined perturber by comparing precession rates of relevant dynamical effects. Furthermore, we demonstrate as examples that in systems with two and three inner planets, the analytical criterion is consistent with numerical simulations using a combination of Gauss’s averaging method and direct N-body integration. Finally, the criterion is applied to observed systems, constraining the orbital parameter space of a possible undiscovered companion. This new stability criterion extends the parameter space in which an inclined companion of multiplanet systems can inhabit.

scholarly journals New Photometric Observations of the Transiting Extrasolar Planet TrES-3b

2011 ◽  
Vol 7 (S282) ◽  
pp. 135-136 ◽  
Author(s):  
M. Vaňko ◽  
M. Jakubík ◽  
T. Krejčová ◽  
G. Maciejewski ◽  
J. Budaj ◽  
...  
Keyword(s):  
Numerical Simulations ◽  
Extrasolar Planet ◽  
Orbital Parameters ◽  
Term Stability ◽  
Long Term Stability ◽  
Photometric Observations

AbstractWe present new transit observations of the transiting exoplanet TrES-3b obtained in the range 2009 – 2011 at several observatories. The orbital parameters of the system were redetermined and the new linear ephemeris was calculated. We performed numerical simulations for studying the long-term stability of orbits.

scholarly journals Towards the characterization of the hot Neptune/super-Earth population around nearby bright stars

2008 ◽  
Vol 4 (S253) ◽  
pp. 502-505 ◽  
Author(s):  
C. Lovis ◽  
M. Mayor ◽  
F. Bouchy ◽  
F. Pepe ◽  
D. Queloz ◽  
...  
Keyword(s):  
Numerical Simulations ◽  
Extrasolar Planets ◽  
Large Population ◽  
Long Term Stability ◽  
Data Points ◽  
Solar Type ◽  
Low Mass ◽  
Orbital Periods

AbstractThe HARPS search for low-mass extrasolar planets has been ongoing for more than 4 years, targeting originally about 400 bright FGK dwarfs in the solar neighbourhood. The published low-mass planetary systems coming from this survey are fully confirmed by subsequent observations, which demonstrate the sub-m/s long-term stability reached by HARPS. The complex RV curves of these systems have led us to focus on a smaller sample of stars, accumulating more data points per star. We perform a global search in our data to assess the existence of the large population of ice giants and super-Earths predicted by numerical simulations of planet formation. We indeed detect about 45 candidates having minimum masses below 30 M⊕ and orbital periods below 50 days. These numbers are preliminary since the existence of these objects has to be confirmed by subsequent observations. However, they indicate that about 30% of solar-type stars may have such close-in, low-mass planets. Some emerging properties of this low-mass population are presented. We finally discuss the prospects for finding transiting objects among these candidates, which may possibly yield the first nearby, transiting super-Earth.

scholarly journals Bio-analytical Approach for Stability Studies of Bendroflumethiazide Materials

2021 ◽  
pp. 195-203
Author(s):  
B. Veeraswami ◽  
V. M. K. Naveen
Keyword(s):  
Stability Study ◽  
Stability Studies ◽  
Dry Extract ◽  
Long Term Stability ◽  
Analytical Stability ◽  
Ich Guidelines ◽  
The Stability ◽  
Efficacy Prediction

In this paper a comprehensive study of stability related, and evidence based best practices of Bio-analytical stability on Bendroflumethiazide drug samples are studied. The proposed approach is very significant and essential for the drugs development process address the specify the acceptancy, purity, efficacy, prediction of strength and quality of the drugs. The stability study constituents several methods like Bench-Top, Auto-sampler, Freeze-Thaw, Dry-extract, Wet-extract, Short-term, long-Term stability studies at relative intervals results the complete stability information about the drug under the proposed and validated method. There ported out comes of this methos shows this drug have good stability according to ICH guidelines.

Long-term stability of laboratory tests and practical implications for quality management

2013 ◽  
Vol 51 (6) ◽  
Author(s):  
Sofie K. Van Houcke ◽  
Hedwig C.M. Stepman ◽  
Linda M. Thienpont ◽  
Tom Fiers ◽  
Veronique Stove ◽  
...  
Keyword(s):  
Reference Intervals ◽  
Biological Variation ◽  
Patient Data ◽  
Analytical Performance ◽  
Internal Quality ◽  
Medical Outcome ◽  
Term Stability ◽  
Long Term Stability ◽  
Analytical Stability

AbstractLong-term stability of analytical performance is required for adequate patient management. We investigated the use of patient data to document test stability, and the relevance of observed instabilities on a surrogate medical outcome. We used multiyear patient and internal quality control (IQC) data from two laboratories for tests to monitor chronic kidney and thyroid disease.We plotted moving means of the 50th percentiles of stratified patient data and of the daily IQC means. We evaluated observed instabilities based on goals inferred from the analytes’ biological variation and investigated their effect on classification of results against reference intervals.Patient and IQC data generally matched well, except for analytes, for which other than analytical variation sources prevailed. Analytical instabilities were predominantly due to reagent/calibrator lot changes, however, for immunoassays also to within-lot instabilities, urging frequent recalibrations. The relevance of biased results on medical decisions ranged from negligible to very pronounced, indicating the need for assessment of analytical performance in relation to quality goals inferred from biological variation.Patient percentiles offer great potential to assess/monitor the medium- to long-term analytical stability of a test within certain constraints. Differences in analytical quality between assays can significantly affect medical outcome.

scholarly journals Bio-Analytical Stability Studies of Nadolol Material

2021 ◽  
pp. 130-140
Author(s):  
B. Veeraswami ◽  
V. M. K. Naveen
Keyword(s):  
Quantitative Measure ◽  
Drug Analysis ◽  
Stability Study ◽  
Stability Studies ◽  
Experimental Conditions ◽  
Long Term Stability ◽  
Analytical Stability ◽  
Ich Guidelines

The best practices of Bio-analytical stability studies on drug samples are very crucial and essential for the drugs development process as it specify the acceptancy, purity, efficacy, prediction of strength and quality of the drugs. The main objective of this stability studies on Nadolol the proposed approach of chromatographic separation was administered in isocratic way by using asymmetric C18 column of 40:60 percent of acetonitrile and 0.1% OPA at a flow rate of 1 ml/min is a quantitative measure for drug analysis in biological matrix for more reliable, selective, reproducible and sensitive.  This stability study constituents several methods like Bench-Top, Auto-sampler, Freeze-Thaw, Dry-extract, Wet-extract, Short-term, long-Term stability studies at various intervals gave the complete stability information about these drugs. The results of these stability studies are accepted based on ICH guidelines represents this drug has a good stability under the present experimental conditions. 

Stability and Change in Emotional Intelligence: Exploring the Transition to Young Adulthood

2005 ◽  
Vol 26 (2) ◽  
pp. 100-106 ◽  
Author(s):  
James D.A. Parker ◽  
Donald H. Saklofske ◽  
Laura M. Wood ◽  
Jennifer M. Eastabrook ◽  
Robyn N. Taylor
Keyword(s):  
High School ◽  
Emotional Intelligence ◽  
Postsecondary Education ◽  
Life Transition ◽  
Full Time ◽  
Major Life ◽  
Long Term Stability ◽  
Time Period ◽  
Transition From High School

Abstract. The concept of emotional intelligence (EI) has attracted growing interest from researchers working in various fields. The present study examined the long-term stability (32 months) of EI-related abilities over the course of a major life transition (the transition from high school to university). During the first week of full-time study, a large group of undergraduates completed the EQ-i:Short; 32 months later a random subset of these students (N = 238), who had started their postsecondary education within 24 months of graduating from high school, completed the measures for a second time. The study found EI scores to be relatively stable over the 32-month time period. EI scores were also found to be significantly higher at Time 2; the overall pattern of change in EI-levels was more than can be attributed to the increased age of the participants.

Multi-Center Calibration of the Second Reference Material for Thromboplastin, Rabbit, Plain, Coded CRM 149R

1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Reference Material ◽  
Standard Error ◽  
Standard Errors ◽  
Sensitivity Index ◽  
Long Term Stability ◽  
Significant Bias ◽  
The Mean ◽  
The Relationship ◽  
International Sensitivity Index

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.

The Stability of the WHO Reference Thromboplastin NIBS & C 67/40

1979 ◽  
Vol 42 (04) ◽  
pp. 1135-1140 ◽  
Author(s):  
G I C Ingram
Keyword(s):  
Human Brain ◽  
Collaborative Study ◽  
Calibration Constant ◽  
Long Term Stability ◽  
Freeze Dried ◽  
Show Evidence ◽  
Human Material ◽  
Reference Preparation ◽  
The Stability

SummaryThe International Reference Preparation of human brain thromboplastin coded 67/40 has been thought to show evidence of instability. The evidence is discussed and is not thought to be strong; but it is suggested that it would be wise to replace 67/40 with a new preparation of human brain, both for this reason and because 67/40 is in a form (like Thrombotest) in which few workers seem to use human brain. A �plain� preparation would be more appropriate; and a freeze-dried sample of BCT is recommended as the successor preparation. The opportunity should be taken also to replace the corresponding ox and rabbit preparations. In the collaborative study which would be required it would then be desirable to test in parallel the three old and the three new preparations. The relative sensitivities of the old preparations could be compared with those found in earlier studies to obtain further evidence on the stability of 67/40; if stability were confirmed, the new preparations should be calibrated against it, but if not, the new human material should receive a calibration constant of 1.0 and the new ox and rabbit materials calibrated against that.The types of evidence available for monitoring the long-term stability of a thromboplastin are discussed.

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