scholarly journals Modelling stochastic signatures in classical pulsators

2020 ◽  
Vol 492 (3) ◽  
pp. 4477-4483
Author(s):  
P P Avelino ◽  
M S Cunha ◽  
W J Chaplin
Keyword(s):  
Phase Variation ◽  
Observation Time ◽  
Relative Amplitude ◽  
Noise Power ◽  
Sufficient Time ◽  
Stochastic Perturbations ◽  
Total Observation Time ◽  
Numerical Tools ◽  
Total Observation ◽  
The Impact

ABSTRACT We consider the impact of stochastic perturbations on otherwise coherent oscillations of classical pulsators. The resulting dynamics are modelled by a driven damped harmonic oscillator subject to either an external or an internal forcing and white noise velocity perturbations. We characterize the phase and relative amplitude variations using analytical and numerical tools. When the forcing is internal the phase variation displays a random walk behaviour and a red noise power spectrum with a ragged erratic appearance. We determine the dependence of the root mean square phase and relative amplitude variations (σΔφ and σΔA/A, respectively) on the amplitude of the stochastic perturbations, the damping constant η, and the total observation time tobs for this case, under the assumption that the relative amplitude variations remain small, showing that σΔφ increases with $t_{\rm obs}^{1/2}$ becoming much larger than σΔA/A for tobs ≫ η−1. In the case of an external forcing the phase and relative amplitude variations remain of the same order, independent of the observing time. In the case of an internal forcing, we find that σΔφ does not depend on η. Hence, the damping time cannot be inferred from fitting the power of the signal, as done for solar-like pulsators, but the amplitude of the stochastic perturbations may be constrained from the observations. Our results imply that, given sufficient time, the variation of the phase associated with the stochastic perturbations in internally driven classical pulsators will become sufficiently large to be probed observationally.

scholarly journals The effects of introducing the Amazonian squirrel monkey on the behavior of the northeast marmoset

2015 ◽  
Vol 45 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Fátima Luciana Miranda CAMAROTTI ◽  
Valdir Luna da SILVA ◽  
Maria Adélia Borstelmann de OLIVEIRA
Keyword(s):  
Squirrel Monkey ◽  
Native Species ◽  
Callithrix Jacchus ◽  
Observation Time ◽  
Saimiri Sciureus ◽  
Significant Difference ◽  
Negative Effect ◽  
Total Observation Time ◽  
Total Observation ◽  
The Impact

The squirrel monkey Saimiri sciureus, an endemic primate of the Amazonian Basin, has been introduced in many localities of the Atlantic Forest biome. Introduced exotic species gain a competitive advantage in their new environment because of a lack of natural predators, competitors or diseases. This advantage can result in a reduction in the resources for the endemic species. The aims of this work were to evaluate the level of adaptation, and monitor the forms of interaction and the impact caused by S. sciureus on the behavior of the native species Callithrix jacchus in the Saltinho Biological Reserve, Tamandaré, Pernambuco, Brazil. The behavior was assessed by use of scan sampling method, every 5 min. A total of 382 h (191 h or 2,292 scans per group) of time sampling was performed. Sixteen interactions were recorded. The interaction index was low and represented 2.4% of the total observation time. Interactions were significantly higher during the dry season (58.5%) relative to the rainy season (41.5%). Callithrix jacchus was intolerant to the presence of S. sciureus and the last one was more tolerant during the interactions. In the presence of S. sciureus, C. jacchus eating, foraging, resting, socializing, and self-grooming behaviors were reduced while alertness was increased. Territorial behavior showed no significant difference. In the presence of S. sciureus, on average, the group of marmosets assembled at a higher layer of the forest stratum. The results might indicate a negative effect of S. sciureus on the native species, C. jacchus.

Stability in Waking-Sleep States in Neonates as a Predictor of Long-Term Neurologic Outcome

PEDIATRICS ◽  
1985 ◽  
Vol 76 (1) ◽  
pp. 52-63
Author(s):  
Cesare T. Lombroso ◽  
Yoichi Matsumiya
Keyword(s):  
Statistical Significance ◽  
Observation Time ◽  
Long Term Outcomes ◽  
Newborn Period ◽  
Waking And Sleep ◽  
Total Observation Time ◽  
Total Observation ◽  
The Individual

Thirty-three full-term neonates were ranked blindly on a scale ranging from the least to the highest "risk" for future neurologic complications on the basis of available perinatal biographies, tests, and examinations performed during the newborn period. Four prolonged polygraphic-behavioral recordings were obtained one week apart beginning at ten days after birth. Five waking and sleep states were scored in each session as percentages of total observation time, giving a total of 20 scores for each baby to be subjected to analysis of variance. These measures also provided individual profile consistency or variability in maintaining waking-sleep states over the selected period of postnatal time. The whole cohort, except three infants who could not be followed adequately, was then reexamined periodically over a period ranging from 3 to 4 years (±6 months) for neurologic and developmental assessments. Except for two scores that produced a low level of statistical significance (P < .05), the other 18 scores were found to be not associated with long-term outcomes. Even the first two scores were not satisfactory discriminators for the outcome of the individual babies. However, when coefficients of concordance (W) were computed from each individual baby profile, significant statistics (P < .001) emerged to indicate good correlations between high or low W values in the newborn period and long-term outcomes. All 17 newborns who had W scores greater than 0.9 were found to be normal at follow-up regardless of the poor ranking given several of them during the newborn period. Among the 13 newborns who had W scores less than 0.9, 11 had a poor clinical outcome at follow-up, though several had been ranked initially as falling within the least "risk" group.

scholarly journals Recurrence of Cholesteatoma - A Retrospective Study Including 1,006 Patients for More than 33 Years

2019 ◽  
Vol 24 (01) ◽  
pp. e18-e23 ◽  
Author(s):  
Patrick Rønde Møller ◽  
Christina Nygaard Pedersen ◽  
Line R. Grosfjeld ◽  
Christian E. Faber ◽  
Bjarki D. Djurhuus
Keyword(s):  
Middle Ear ◽  
Total Sample ◽  
Observation Time ◽  
Benign Tumors ◽  
Retraction Pocket ◽  
Risk Of Recurrence ◽  
Middle Ear Cholesteatoma ◽  
Total Observation Time ◽  
Total Observation ◽  
First Time

Abstract Introduction Cholesteatomas are benign tumors consisting of skin, and growing inside a retraction pocket in the tympanic membrane. Cholesteatomas can occupy the entirety of the middle ear, and are known for their osteolytic capabilities. Surgery is the only curative treatment for cholesteatomas. Objective To describe the risk of recurrence after first-time surgically-treated middle-ear cholesteatoma (STMEC1) on the island of Funen from 1983 to 2015. Methods Cases of STMEC1 were identified in the Danish National Hospital Register. The medical records were reviewed. Time-to-event analyses were applied. The ears were followed from STMEC1 to a secondary cholesteatoma, emigration, death, or end of follow-up. Results Records from 1,006 patients with STMEC1 were reviewed. A total of 54 patients were submitted to surgery on both ears. The total sample consisted of 1,060 ears with STMEC1; 300 were children's (< 16 years) ears, and 760 were adult's ears. The total observation time was of 12,049 years.The overall estimated proportion with recurrence 5 years after surgery was of 37% in children and of 15% in adults. The older the child was at the first surgery, the risk decreased by 7% per year. In children, canal wall up (CWU) mastoidectomy without obliteration was associated with a hazard ratio for recurrence of 1.9 (95% confidence interval [95%CI]: 1.2–3.0) compared with CWU with obliteration. Conclusion Compared with adults, children were had 2.6 times more risk of recurrence. Procedures performed without mastoidectomy had the lowest risk of recurrence. In children, obliteration was associated with a significantly lower risk of recurrence. However, patients were not randomized regarding the surgical approach; thus, the association between approach and risk of recurrence was likely influenced by confounding factors.

Incidence and severity of prostate cancer (PCa) in 792 hypogonadal men with and without long-term testosterone therapy (TTh): Results from a controlled registry study.

2018 ◽  
Vol 36 (6_suppl) ◽  
pp. 167-167
Author(s):  
Ahmad Haider ◽  
Karim Sultan Haider
Keyword(s):  
Radical Prostatectomy ◽  
Gleason Score ◽  
Transrectal Ultrasound ◽  
Digital Rectal Examination ◽  
Tumor Grade ◽  
Tumor Stage ◽  
Observation Time ◽  
Testosterone Undecanoate ◽  
Total Observation Time ◽  
Total Observation

167 Background: There is no evidence that TTh in hypogonadal men increases PCa incidence or severity. A US-Scandinavian group recently found that men receiving TTh had lower risk of aggressive PCa (Loeb S et al., J Clin Oncol 2017; 35:1430-6). Methods: 412 men with testosterone ≤350 ng/dL and symptoms received testosterone undecanoate 1000 mg every 3 months for up to 12 years. 380 hypogonadal men (57-74) opted against TTh. Median follow-up: 9 years. Total observation time covered approximately 6,400 patient-years. Prostate volume (PV) and PSA were measured and digital rectal examination/transrectal ultrasound performed before treatment/observation initiation and then every 3-6 months (T-group) or once or twice per year (CTRL). Biopsies were performed when indicated according to EAU guidelines. Results: In the T-group, 11 men (2.7%) were diagnosed with PCa. In CTRL, 34 (8.9%) were diagnosed with PCa. The incidence per 10,000 years was 33 in the T-group and 108 in CTRL. The mean baseline age of PCa patients was 65.2 years in the T-group and 64.3 in CTRL. All PCa diagnoses in the T-group were made within the first 18 months of treatment initiation. In CTRL, PCa was diagnosed at any time during the observation time. In the T-group, radical prostatectomy was performed in all men. All but 1 patient had a Gleason score (GS) ≤6, and all but 1 a predominant GS of 3. Tumor grade was G2 in all 11 (100%), tumor stage T2a in 7 (64%), T2b in 3 (27%), and T2c in 1 (9%) patient(s). In CTRL, radical prostatectomy was performed in all but 6 patients. GS was > 6 in all 34 patients. 7 men had a GS of 7, 17 a GS of 8, and 10 a GS of 9. 2 men had a predominant Gleason score of 3, 22 had 4, and 10 had 5. Tumor grade was G2 in 6 (17.6%) and G3 in 28 (82.4%) patients, tumor stage T2c in 1 (0.3%), T3a in 3 (8.8%), T3b in 13 (38.2%) and T3c in 17 (50%) patients. In CTRL, biochemical recurrence occurred in 8 (23.5%) patients. These patients received androgen deprivation therapy (ADT). 10 (29.4%) patients died of whom 5 were on ADT. In the T-group, there were no biochemical recurrences or deaths during the observation time. Conclusions: In hypogonadal men, TTh may decrease PCa incidence compared to CTRL. PCa was less severe in the T-group.

scholarly journals A decadal cirrus clouds climatology from ground-based and spaceborne lidars above the south of France (43.9° N–5.7° E)

2013 ◽  
Vol 13 (14) ◽  
pp. 6951-6963 ◽  
Author(s):  
C. Hoareau ◽  
P. Keckhut ◽  
V. Noel ◽  
H. Chepfer ◽  
J.-L. Baray
Keyword(s):  
Observation Time ◽  
Cirrus Clouds ◽  
Cirrus Cloud ◽  
Upper Troposphere ◽  
Cloud Parameters ◽  
Cloud Properties ◽  
Total Observation Time ◽  
The Mean ◽  
Ground Based Lidar ◽  
Total Observation

Abstract. This study provides an analysis of cirrus cloud properties at midlatitude in the southern part of France from ground-based and spaceborne lidars. A climatology of cirrus cloud properties and their evolution over more than 12 yr is presented and compared to other mid-latitude climatological studies. Cirrus clouds occur ~37% of the total observation time and remain quasi-constant across seasons with a variation within ~5% around the mean occurrence. Similar results are obtained from CALIOP and the ground-based lidar, with a mean difference in occurrence of ~5% between both instruments. From the ground-based lidar data, a slight decrease in occurrence of ~3% per decade is observed but found statistically insignificant. Based on a clustering analysis of cirrus cloud parameters, three distinct classes have been identified and investigations concerning their origin are discussed. Properties of these different classes are analysed, showing that thin cirrus in the upper troposphere represent ~50% of cloud cover detected in summer and fall, decreasing by 15–20% for other seasons.

The Modified Transit Method of Observation With the Wild GAK-1 Gyro Theodolite

1970 ◽  
Vol 24 (1) ◽  
pp. 108-116 ◽  
Author(s):  
G.G. Bennett
Keyword(s):  
Turning Point ◽  
Reduction Process ◽  
Observation Time ◽  
Theory And Practice ◽  
Experimental Series ◽  
Reduction Methods ◽  
Total Observation Time ◽  
Total Observation ◽  
Transit Method

In UNISURV Report No. 15, 1969, this author gave the theory and practice of methods that have been developed for the transit and turning point methods of observation with the gyro theodolite to reduce the total observation time. Since the publication of that report, a longer experimental series of observations has been made to test the repeatability of the modified transit method and to assess the reliability of the reduction process. The results of this experimental series are given together with an analysis of various reduction methods.

Motion of bones and volume changes in the neurocranium after craniectomy in Crouzon's disease

1979 ◽  
Vol 50 (4) ◽  
pp. 494-498 ◽  
Author(s):  
Bodil Rune ◽  
Göran Selvik ◽  
Sven Kreiborg ◽  
Karl-Victor Sarnäs ◽  
Erik Kågström
Keyword(s):  
Radiation Dose ◽  
Observation Time ◽  
Sagittal Suture ◽  
Volume Changes ◽  
Content Type ◽  
Metallic Implants ◽  
Total Observation Time ◽  
Total Observation ◽  
High Degree ◽  
Fine Print

✓ Craniectomy was performed on a boy with Crouzon's disease at 22 months of age. Metallic implants (tantalum balls, 0.5 mm in diameter) were inserted in the calvaria during surgery, and the child was examined postoperatively by roentgen stereometry at intervals of about 100 days (total observation time, 309 days). The thyroid radiation dose was 250 µGy for one examination. The effect of craniectomy was recorded with a high degree of accuracy in terms of motion of bones and volume changes in the calvaria. Expansion occurred almost entirely through motion of free bone flaps in the frontal region, while a linear craniectomy in the region of the sagittal suture caused small changes. The rate of expansion decreased rapidly and stabilization was recorded about 250 days after surgery.

THE DIURNAL ETHOLOGY OF THE SOUTHERN GREEN STINK BUG, NEZARA VIRIDULA (L.), IN COWPEAS

1986 ◽  
Vol 21 (2) ◽  
pp. 175-184 ◽  
Author(s):  
Jeffrey A. Lockwood ◽  
Richard N. Story
Keyword(s):  
Time Of Day ◽  
Observation Time ◽  
Nezara Viridula ◽  
Stink Bug ◽  
Mating Status ◽  
Southern Green Stink Bug ◽  
Green Stink Bug ◽  
Total Observation Time ◽  
Total Observation ◽  
Walking Time

A behavioral catalogue of the adult southern green stink bug, Nezara viridula (L.), was developed from observations taken in a cowpea field. A total of 23 behaviors are described, and the effects of sex, mating status, time of day, height on the plant, and substrate on these behaviors are quantified. Of the seven most common behaviors, which occupied 97% of the total observation time, sex significantly influenced the duration and/or frequency of kicking, rocking, and mating. Mating status significantly affected the frequency of antennal waving and walking. Time of day had a significant effect on the duration and/or frequency of resting, antennal waving, feeding, kicking, and mating. Height on the plant significantly affected the duration and/or frequency of resting, antennal waving, walking, feeding, kicking, rocking, and mating. Substrate significantly influenced the duration and/or frequency of antennal waving, feeding, kicking, and mating. The proportion of time spent basking on the tops of plants decreased significantly from morning to noon and from noon to afternoon.

Peritonitis during Continuous Ambulatory Peritoneal Dialysis (CAPD): Risk Factors, Clinical Severity, and Pathogenetic Aspects

1988 ◽  
Vol 8 (4) ◽  
pp. 253-263 ◽  
Author(s):  
Anders Tranæus ◽  
Olof Heimbürger ◽  
Bengt Lindholm
Keyword(s):  
Risk Factors ◽  
Peritoneal Dialysis ◽  
Continuous Ambulatory Peritoneal Dialysis ◽  
Patient Characteristics ◽  
Observation Time ◽  
Clinical Severity ◽  
First Episode ◽  
First Year ◽  
Total Observation Time ◽  
Total Observation

This study of 228 episodes of peritonitis occurring during a total observation time of 2365 treatment months over a six-year period in a uniformly selected, trained, and treated continuous ambulatory peritoneal dialysis (CAPD) population (N = 124) showed the following major findings: 1) the risk of developing peritonitis was 55% within the first year and 89% within the first three years on CAPD; 2) high age (≥60 years) and year of CAPD start were risk factors for peritonitis; 3) neither sex, diabetes, or hypoalbuminemia were found to be risk factors for peritonitis; 4) the year of start, but neither the degree of severity, nor the time of the first episode affected the risk of developing a second episode of peritonitis; 5) no specific characteristics were identified in patients with the highest mean peritonitis incidence or in the patients without peritonitis; 6) in 27% of all episodes, turbidity of the dialysate was the only clinical finding; 7) the proportion of asymptomatic episodes was lower in patients ≥ 60 years; 8) the degree of clinical severity of peritonitis was not statistically influenced by the number of previous episodes; 9) the cause of peritonitis was established in only 26% of all cases; and 10) no statistical association was found between the cause of peritonitis and patient characteristics.

Agitation in Nursing Home Residents: The Role of Gender and Social Context

2000 ◽  
Vol 12 (4) ◽  
pp. 495-511 ◽  
Author(s):  
Louis D. Burgio ◽  
Frieda R. Butler ◽  
David L. Roth ◽  
J. Michael Hardin ◽  
Chuan-Chieh Hsu ◽  
...  
Keyword(s):  
Nursing Home ◽  
Significant Proportion ◽  
Nursing Home Residents ◽  
Observation Time ◽  
Computer Assisted ◽  
Direct Observations ◽  
Total Observation Time ◽  
Clinically Significant ◽  
Total Observation ◽  
Sequential Analyses

We investigated the relationship among gender of resident, staff social interaction, and agitation in 46 (31 male and 15 female) nursing home residents with clinically significant agitation. Direct observations were conducted of resident behaviors and environmental contextual events using a computer-assisted, real-time observational system. The system recored frequency, duration, and temporal sequencing of events. Results show that female residents displayed almost three times the amount of agitation as male residents (35% vs. 13% of total observation time, respectively), although men in the study were more likely to receive psychoactive drugs for their agitation. Staff spent similar amounts of time verbally interacting and touching male and female residents. Sequential analyses were conducted to examine the likelihood of staff verbal and touch interactions both preceding and following resident agitation using Bakeman and Quera's (1995) SDIS-GSEQ program. Results suggest that staff touch and verbal interaction elicit agitation in a significant proportion of residents. Once agitation occurs, staff were likely to respond by interacting verbally, but not physically, with the resident.

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