scholarly journals Variable Be Stars in h and χ Persei

1987 ◽  
Vol 92 ◽  
pp. 505-508
Author(s):  
C.L. Waelkens ◽  
P. Lampens ◽  
J. Cuypers ◽  
J. Denoyelle ◽  
D. Heynderickx ◽  
...  
Keyword(s):  
Age Groups ◽  
Variable Stars ◽  
Age Group ◽  
Be Stars ◽  
Stellar Content ◽  
Photometric Variability ◽  
Double Cluster

The double cluster h and χ Persei has since long been known to be rich in Be stars (Trumpler, 1926). It belongs to an age group in which various types of variable stars occur (Mermilliod, 1981). Other clusters of this age group are NGC 3293, the cluster that is richest in β Cephei variables (Balona and Engelbrecht, 1983), IC 2581, NGC 4755, and NGC 6871. The comparison of the characteristics of variable stars in all these clusters and in clusters of other age groups could reveal to which extent the cluster stellar content is determined by age and by other parameters, such as galactic location, and so metallicity. Since h and χ Persei are very rich clusters that have not yet been studied intensively as far as stellar variability is concerned (Percy, 1972), we have undertaken a study of the photometric variability of the brightest stars in the double cluster. Our first interest was to detect β Cephei variables, but it rapidly turned out that the double cluster contains a considerable amount of highly variable Be stars.

scholarly journals Main-sequence broadening, Be stars, and stellar rotation inhand χ Persei

1994 ◽  
Vol 162 ◽  
pp. 151-152
Author(s):  
J. Denoyelle ◽  
C. Aerts ◽  
C. Waelkens
Keyword(s):  
Main Sequence ◽  
Large Fraction ◽  
Variable Stars ◽  
Theoretical Studies ◽  
Be Stars ◽  
Stellar Rotation ◽  
B Stars ◽  
Fundamental Parameters ◽  
Magnitude Diagram ◽  
Double Cluster

The double cluster h andxPersei is one of the richest clusters containing early-B stars, and therefore is important for observational and theoretical studies on the fundamental parameters of massive stars. The colour-magnitude diagram of the double cluster shows an important scatter (see Figure 1). It has long been known thathandxPersei are extremely rich in Be stars (Slettebak 1968). Our previous contention (Waelkens et al. 1990) that the large-amplitude variable stars we discovered are also Be stars, could be confirmed for a few objects. Rotation velocities for stars inhandxPersei are usually high, which is not surprising in view of the large fraction of Be stars.

scholarly journals Search for Pulsational Instability among h Persei Stars

1995 ◽  
Vol 155 ◽  
pp. 299-300
Author(s):  
J. Krzesinski
Keyword(s):  
Northern Hemisphere ◽  
Open Clusters ◽  
Age Group ◽  
Be Stars ◽  
Double Cluster

AbstractThe northern-hemisphere double cluster h and χ Persei is one of the richest young open clusters. At least half of the brightest stars in the cluster appear to be variables and most of them axe Be stars. Till now there was no evidence for the presence of β Cephei stars in the cluster. It is remarkable that the similar age southern cluster NGC 3293 and other clusters belonging to the same age group are documented as clusters in which β Cephei stars have been observed. In this work we report finding one suspected β Cephei-like object, basing on our own observations.

scholarly journals Comparative Study of Young Open Clusters: Age Determination and Stellar Content

1980 ◽  
Vol 85 ◽  
pp. 245-245
Author(s):  
J. C. Mermilliod
Keyword(s):  
Comparative Study ◽  
Age Groups ◽  
Age Determination ◽  
Open Clusters ◽  
Red Giants ◽  
Be Stars ◽  
Stellar Content ◽  
Blue Stragglers ◽  
The Mean ◽  
Hr Diagram

75 young open clusters have been divided into 14 age groups on the basis of their MV/U-B diagrams. Composite HR diagrams have been constructed and empirical isochronous curves estimated (Figure 1). The left envelope defines a ZAMS. The mean position of the red giants in the HR diagram has been investigated, as well as the occurrence and location of Ap, Am and Be stars and of blue stragglers. Red giants appear mainly in clumps (shaded area).

scholarly journals Correlation Between Spectrum Characteristics and Photometric Behaviour of Be Stars

1982 ◽  
Vol 98 ◽  
pp. 65-67
Author(s):  
G. A. Ponomareva
Keyword(s):  
Emission Line ◽  
Variable Stars ◽  
Absorption Lines ◽  
Be Stars ◽  
Photometric Variability ◽  
Spectrum Characteristics ◽  
Statistical Relationships

Based upon a sample of 140 B0-A0 emission-line stars contained in “A Photographic Atlas of Be stars” statistical relationships between variable stars and Be stars are examined. It is found that 44 % of all the stars of the sample show some kind of photometric variations. The stars with narrow metallic absorption lines display relatively more intense photometric activity. Proceeding from this conclusion, the photometric variability of two stars HD 50138 and HD 193182 can be predicted.

The Effect of Collagen Mediated Platelet Release on Plasma Prekallikrein Activation

1984 ◽  
Vol 51 (01) ◽  
pp. 037-041 ◽  
Author(s):  
K M Weerasinghe ◽  
M F Scully ◽  
V V Kakkar
Keyword(s):  
Platelet Aggregation ◽  
Healthy Volunteers ◽  
Platelet Rich Plasma ◽  
Age Groups ◽  
Inhibitory Effect ◽  
Age Group ◽  
Platelet Factor ◽  
Activated Platelets ◽  
Platelet Release ◽  
Collagen Treatment

SummaryCollagen mediated platelet aggregation caused -5.6 ± 6.7% inhibition and +39.1 ± 15.2% potentiation of prekallikrein activation in plasma from normal healthy volunteers between 20–40 and 50–65 years of age, respectively (n = 15, p <0.01). The amouns of platelet factor-four (PF4) released in the two groups were not significantly different. Collagen treatment in the presence of indomethacin caused +11.5 ± 3.6% and +59.6 ± 19.5% potentiation in the 20–40 and 50–65 age groups respectively (p <0.02). Adrenaline mediated platelet aggregation caused -55.2 ± 7.1% and -35.2 ± 8.3% inhibition in the 20–40 and 50–65 age groups, respectively. Collagen treatment of platelet-deficient-plasma and platelet-rich-plasma in EDTA also caused potentiation of prekallikrein activation.The results indicate that the observed degree of prekallikrein activation after platelet aggregation is a net result of the inhibitory effect of PF4 and the potentiatory effect of activated platelets. The potentiatory effect was greater after collagen treatment as compared to adrenaline treatment, and in the 50–65 age group as compared to the 20–40 age group.

Health and Nutritional Status of Orphan Children’s Living in Orphanages with Special Reference to District Anantnag of Jammu and Kashmir

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Mashkoor Ahmad Lone ◽  
Dr. P. Ganesan
Keyword(s):  
Age Groups ◽  
Indian Academy ◽  
Dental Enamel ◽  
Nutritional Intake ◽  
Age Group ◽  
Asian Countries ◽  
Jammu And Kashmir ◽  
Material Resources ◽  
Height For Age ◽  
Weight For Age

The practice of placing deprived children having least or no emotional and material resources, in orphanages has since long been prevailing in socio -economically poor Asian countries. A sample of 30 children residing in orphanage in district Anantnag in the age group of 13-18 years was selected for the present study. Most of the children were found socially and psychologically disturbed. As per Indian Academy Paediatrics (IAP) classification with respect to weight for age the condition was not bad that as approximately 67% percent of the children were found to be normal. In the same way height for age as per Waterloo’s classification shown that more than half of the children were normal. On clinical examination approximately 47% of children were normal, while as rest were suffering from dispigmentation of hair, moon face, xerosis of skin cheilosis, magenta tongue, spongy bleeding gums, oedema, conjuctival xerosis, and mottled dental enamel. The findings indicated that nutritional intake was deficient for all nutrients when compared to, Recommended Daily Allowances Chart (RDA) for all age groups which may be linked to poor planning of menus in orphanages.

COVID-19 Epigenetics and Implications for Public Health

Coronaviruses ◽  
2020 ◽  
Vol 01 ◽  
Author(s):  
Verda Tunalıgil ◽  
Gülsen Meral ◽  
Ahmet Katı ◽  
Dhrubajyoti Chattopadhyay ◽  
Amit Kumar Mandal
Keyword(s):  
Chronic Conditions ◽  
Empirical Investigation ◽  
Age Groups ◽  
Infectious Agent ◽  
Well Being ◽  
Epigenetic Mechanisms ◽  
Age Group ◽  
Epigenetic Changes ◽  
Patient Groups ◽  
Epigenetic Processes

Abstract:: Epigenetic changes in COVID-19 host, a pandemic-causing infectious agent that globally incapacitated communities in varying complexities and capacities are discussed, proposing an analogy that epigenetic processes contribute to disease severity and elevate the risk for death from infection. Percentages of hospitalization, with and without intensive care, in the presence of diseases with increased ACE2 expression, were compared, based on the best available data. Further analysis compared two different age groups, 19-64 and ≥65 years of age. The COVID-19 disease is observed to be the most severe in the 65-and-higher-age group with preexisting chronic conditions. This observational study is a non-experimental empirical investigation of the outcomes of COVID-19 in different patient groups. Results are promising for conducting clinical trials with intervention groups. To ultimately succeed in disease prevention, researchers and clinicians must integrate epigenetic mechanisms to generate valid prescriptions for global well-being.

scholarly journals Tower Running—Participation, Performance Trends, and Sex Difference

2020 ◽  
Vol 17 (6) ◽  
pp. 1902 ◽  
Author(s):  
Daniel Stark ◽  
Stefania Di Gangi ◽  
Caio Victor Sousa ◽  
Pantelis Nikolaidis ◽  
Beat Knechtle
Keyword(s):  
Sex Differences ◽  
Statistical Model ◽  
Sex Difference ◽  
Random Effects ◽  
Age Groups ◽  
Repeated Measurements ◽  
Stair Climbing ◽  
Age Group ◽  
Performance Trends ◽  
The Difference

Though there are exhaustive data about participation, performance trends, and sex differences in performance in different running disciplines and races, no study has analyzed these trends in stair climbing and tower running. The aim of the present study was therefore to investigate these trends in tower running. The data, consisting of 28,203 observations from 24,007 climbers between 2014 and 2019, were analyzed. The effects of sex and age, together with the tower characteristics (i.e., stairs and floors), were examined through a multivariable statistical model with random effects on intercept, at climber’s level, accounting for repeated measurements. Men were faster than women in each age group (p < 0.001 for ages ≤69 years, p = 0.003 for ages > 69 years), and the difference in performance stayed around 0.20 km/h, with a minimum of 0.17 at the oldest age. However, women were able to outperform men in specific situations: (i) in smaller buildings (<600 stairs), for ages between 30 and 59 years and >69 years; (ii) in higher buildings (>2200 stairs), for age groups <20 years and 60–69 years; and (iii) in buildings with 1600–2200 stairs, for ages >69 years. In summary, men were faster than women in this specific running discipline; however, women were able to outperform men in very specific situations (i.e., specific age groups and specific numbers of stairs).

scholarly journals Ten-year trends of hypertension treatment and control rate in Korea

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kwang-il Kim ◽  
Eunjeong Ji ◽  
Jung-yeon Choi ◽  
Sun-wook Kim ◽  
Soyeon Ahn ◽  
...  
Keyword(s):  
Age Groups ◽  
Favorable Effect ◽  
Age Group ◽  
Hypertension Treatment ◽  
Treatment Rate ◽  
Cross Sectional ◽  
The Past ◽  
Nationally Representative ◽  
Multistage Sampling ◽  
And Control

AbstractWe analyzed the Korean National Health and Nutrition Examination Survey (KNHANES) database to determine the trends of hypertension treatment and control rate in Korea over the past 10 years. In addition, we tried to investigate the effect of chronic medical conditions on hypertension management. We investigated the hypertension prevalence, awareness, treatment, and control rate from 2008 to 2017. KNHANES, which uses a stratified multistage sampling design, is a cross-sectional, nationally representative survey conducted by the Korean government. A total of 59,282 adults (≥ 20 years) were included, which was representative of the total population of around 40 million Koreans per year. The mean age was 50.7 ± 16.4 years and 42.6% were male. The prevalence of hypertension, hypercholesterolemia, diabetes mellitus, and obesity significantly increased over the 10 years. During this period, the hypertension treatment and control rate significantly improved. Hypertension treatment rate was significantly lower in the younger age group compared to the older age group, but the control rate among the treated patients was not significantly different between age groups. The treatment and control rates of hypertension were higher in patients with multimorbidity, which implies that it has a favorable effect on the treatment and control of hypertension. Hypertension treatment and control rate have improved over the past 10 years. The higher treatment and control rate in patients with multimorbidity suggest that the more aggressive surveillance might be associated with the improvement of hypertension treatment and control rate in Korea.

scholarly journals A Study of Varicella Seroprevalence in a Pediatric and Adolescent Population in Florence (Italy). Natural Infection and Vaccination-Acquired Immunization

Vaccines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 152
Author(s):  
Beatrice Zanella ◽  
Angela Bechini ◽  
Benedetta Bonito ◽  
Marco Del Riccio ◽  
Alessandra Ninci ◽  
...  
Keyword(s):  
Natural Infection ◽  
Age Groups ◽  
Varicella Vaccination ◽  
Age Group ◽  
Disease Notification ◽  
Test Elisa ◽  
Vaccine Schedule ◽  
Almost All ◽  
Vaccination Campaigns ◽  
Dose Vaccine

Background: Varicella is a well-known infectious disease that can have severe complications, also in young children. The Universal Varicella Vaccination (UVV) program was introduced in Tuscany (Italy) in 2003, with a two-dose vaccine schedule given to children between their 13th and 15th month, and at 5–6 years old, as a monovalent for varicella (V) or tetravalent (measles, mumps, rubella and varicella (MMRV)) formulation. Although varicella notifications have dramatically fallen in the last two decades, varicella disease underreporting remains a challenge. Methods: A qualitative immunoenzymatic test (ELISA) was used to measure the presence of anti-varicella antibodies in 165 sera of subjects aged 1–18 years residing in the province of Florence (Italy). Information regarding the anamnestic and vaccination status (including disease notification) was also collected. Results: Our study showed an overall varicella seropositivity of 75.8% (reaching the maximum at 96.3% in the 15–18 years age group). We found that varicella disease notification had been recorded for only 7/165 subjects; however, since 42/165 recalled having had the disease, we can hypothesize that some of them must have been underreported. Furthermore, our study showed that the presence of antibodies after the varicella vaccination remained over time, lasting up to 12 years. Conclusions: Although varicella seroprevalence is <95% in almost all our age groups (except for the 15–18 years age group), our data are encouraging and reflect the success of the introduction of the UVV program and the vaccination campaigns promoted in the Tuscany region.

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