scholarly journals Variable Magellanic HMXB Sources versus Variable ULX Sources: Nothing to Brag about the ULX Sources

Galaxies ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 70
Author(s):  
Dimitris M. Christodoulou ◽  
Silas G. T. Laycock ◽  
Rigel Cappallo ◽  
Ankur Roy ◽  
Sayantan Bhattacharya  ◽  
...  
Keyword(s):  
Normal Distribution ◽  
Meta Analysis ◽  
Continuous Distribution ◽  
High Mass ◽  
P Value ◽  
Data Sets ◽  
Significance Level ◽  
X Ray ◽  
Log Normal ◽  
Ks Test

We carry out a meta-analysis of ultraluminous X-ray (ULX) sources that show large variabilities (by factors of >10) between their highest and lowest emission states in the X-ray energy range of 0.3–10 keV. We are guided by a recent stringent compilation of 25 such X-ray sources by Song et al. We examine the relation of logN versus logSmax, where N is the number of sources radiating above the maximum-flux level Smax. We find a strong deviation from all previously determined slopes in various high-mass X-ray binary (HMXB) samples. In fact, the ULX data clearly show a slope of −0.91. Thus, ULX sources do not appear to be uniform and isotropic in our Universe. We compare the ULX results against the local X-ray luminosity function of HMXBs in the Small Magellanic Cloud (SMC) constructed from our latest library that includes 41 Chandra 0.3–8 keV sources and 56 XMM-Newton 0.2–12 keV sources. The ULX data are not drawn from the same continuous distribution as the SMC data (the ULX data peak at the low tails of the SMC distributions), and none of our data sets is drawn from a normal distribution or from a log-normal distribution (they all show marked excesses at both tails). At a significance level of α=0.05 (2σ), the two-sample p-value of the Kolmogorov–Smirnov (KS) test gives p=4.7×10−3<α for the ULX versus the small Chandra sample and p=1.1×10−5<<α for the ULX versus the larger XMM-Newton sample, respectively. This adds to the evidence that ULX sources are not simply the higher end of the known local Be/X-ray pulsar distribution, but they represent a class of X-ray sources different from the young sources found in the SMC and in individual starburst galaxies. On the other hand, our two main SMC data sets are found to be statistically consistent, as they are drawn from the same continuous parent distribution (null hypothesis H0): at the α=0.05 significance level, the two-sample KS test shows an asymptotic p-value of 0.308>α, which tells us to accept H0.

scholarly journals Multiwavelength Observations of AB Doradus

2014 ◽  
Vol 31 ◽  
Author(s):  
O.B. Slee ◽  
N. Erkan ◽  
M. Johnston-Hollitt ◽  
E. Budding
Keyword(s):  
Impulsive Phase ◽  
High Energy ◽  
High Dispersion ◽  
Data Sets ◽  
Full Data ◽  
Multiple Star ◽  
Significance Level ◽  
X Ray ◽  
Low Mass ◽  
Compact Array

AbstractWe have observed the bright, magnetically active multiple star AB Doradus in a multiwavelength campaign centring around two large facility allocations in November 2006 and January, 2007. Our observations have covered at least three large flares. These flares were observed to produce significant hardening of the X-ray spectra during their very initial stages. We monitored flare-related effects using the Suzaku X-ray satellite and the Australia Telescope Compact Array (ATCA) at 3.6 and 6 cm. Observations at 11 and 21 cm were also included, but they were compromised by interference. Optical monitoring was also provided by broadband B and V photometry and some high-dispersion spectrograms. From this multiwavelength coverage we find that the observed flare effects can be mainly associated with a large active region near longitude zero. The second major X-ray and microwave flare of Jan 8, 2007 was observed with a favourable geometry that allowed its initial high-energy impulsive phase to be observed in the higher frequency range of Suzaku’s XIS detectors. The fractional circular polarisation (Stokes V/I) was measured in the uv data for the complete runs, for 25 min integrations and, at 4.80 GHz, for 5 min integrations, using the radio data of Nov 21 2006 and Jan 08 2007. Most of the full data sets showed V/I fractions from AB Dor B that were significant at greater than the 3σ level. In several of the 5 min integrations at 4.80 and 8.64 GHz this fraction reached a significance level between 3 and 9σ. Lack of angular resolution prevented identification of these high V/I values with one or other of the two low-mass red-dwarf components of AB Dor B.

scholarly journals Determinants of Perinatal birth Asphyxia among Newborns in Ethiopia: A Systematic Review and Meta-analysis of Observational Studies Protocol

2020 ◽  
Author(s):  
Abay Woday ◽  
Muluken Dessalegn ◽  
Setognal Birara ◽  
Kusse Urmale ◽  
Gebeyaw Biset ◽  
...  
Keyword(s):  
Systematic Review ◽  
Observational Studies ◽  
Associated Factors ◽  
Meta Analysis ◽  
Statistical Significance ◽  
Birth Asphyxia ◽  
Cochrane Library ◽  
P Value ◽  
African Countries ◽  
Significance Level

Abstract Background: Birth asphyxia among newborns accounted for nearly fifty percent of neonatal mortality in sub-Saharan African countries. This scenario has been worst in Ethiopia where every two out of three deaths attributed to birth asphyxia among these babies. Moreover, studies conducted in Ethiopia are highly variable and inconclusive to estimate the pooled prevalence and risk factors of birth asphyxia. Objective: This study aims to analyses collectively and systematically the prevalence of birth asphyxia and associated factors among newborns in Ethiopia.Methods: The protocol for this review is registered at PROSPERO with registration number CRD42020158224. A comprehensive online databases (PubMed, HINARI, Scopus, EMBASE, Science direct, and Cochrane library database), Google Scholar, African Journals online, other gray and online repository accessed studies will be searched using different search engines. In addition, maternity & infant care databases uploaded at Ethiopian Health Development Journal and Ethiopian Journal of Health Sciences will be searched until June 30, 2020. Newcastle-Ottawa Quality Assessment Scale (NOS) will be used for critical appraisal of studies.. Three reviewers will screen all retrieved articles, conduct data extraction, and then critically appraise all identified studies. All identified observational studies reporting the prevalence of birth asphyxia and associated factors among neonates in Ethiopia will be considered. The analysis of data will be done using STATA 11.0 statistical software. We will demonstrate pooled estimates and determinants of birth asphyxia with effect size and 95% confidence interval. Heterogeneity among the included studies will be assessed through the Cochrane Q-test statistics and I2 test. Publication bias will be checked using funnel plot and egger’s test. Finally, statistical significance level will be declared at a p-value of less than 0.05. Discussion: the result from this systematic review will inform and guide health policy planners to invest limited resources on maternal and neonatal health. Furthermore, it will be a stimulus for future cumulative meta-analysis researchers in developing nations.

X-ray particle-size broadening

1986 ◽  
Vol 42 (1) ◽  
pp. 6-13 ◽  
Author(s):  
S. Rao ◽  
C. R. Houska
Keyword(s):  
Particle Size ◽  
Normal Distribution ◽  
Variation Coefficient ◽  
Column Height ◽  
X Ray Diffraction ◽  
Diffraction Profile ◽  
X Ray ◽  
The Mean ◽  
Log Normal ◽  
Log Normal Distribution

X-ray diffraction profiles and Fourier coefficients are given for particles distributed according to experimentally verified size distributions. Calculations are based upon the log normal distribution of sphere diameters and intercept lengths in addition to a normal distribution of column heights. It is found that the diffraction profile is not sensitive to the fine details of the distribution but rather the mean column height and the column-height variation coefficient. Errors in particle-size determinations will result from an improper choice of the variation coefficient. Two simplified models are given that describe the diffraction profiles for a large range of variation coefficients.

scholarly journals Detection of Non-Normality in Data Sets and Comparison between Different Normality Tests

2020 ◽  
pp. 1-20 ◽  
Author(s):  
Biu O. Emmanuel ◽  
Nwakuya T. Maureen ◽  
Nduka Wonu
Keyword(s):  
Sample Size ◽  
Normal Distribution ◽  
Small Sample ◽  
Data Sets ◽  
Normality Test ◽  
Sample Data ◽  
Kolmogorov Smirnov ◽  
Level Of Significance ◽  
Ks Test ◽  
Test For Normality

The paper provides five tests of data normality at different sample sizes. The tests are the Shapiro-Wilk (SW) test, Anderson-Darling (AD) test, Kolmogorov-Smirnov (KS) test, Ryan-Joiner (RJ) test, and Jarque-Bera (JB) test. These tests were used to test for normality for two secondary data sets with sample size (155) for large and (40) for small; and then test the simulated scenario with standard normal “N(0,1)” data sets; where the large samples of sizes (150, 140, 130, 130, 110 and 100) and small samples of sizes (40. 35, 30, 25, 20, 15 and 10) are considered at two levels of significance (5% and 10%). However, the aim of this paper is to detect and compare the performance of the different normality tests considered. The normality test results shows Kolmogorov-Smirnov (KS) test is a most powerful test than other tests since it detect the simulated large sample data sets do not follow a normal distribution at 5%, while for small sample sizes at 5% level of significance; the results showed the Jarque-Bera (JB) test is a most powerful test than other tests since it detects that the simulated small sample data do not follow a normal distribution at 5%. This paper recommended JB test for normality test when the sample size is small and KS test when the sample size is large at 5% level of significance.

Maternal Knowledge Factor, Maternal Age and Maternal Parity Associated with Genesis of Normal Delivery at Palembang Hospital of Bari Year 2017

2018 ◽  
Vol 1 (1) ◽  
pp. 43-50
Author(s):  
Juliana Widyastuti Wahyuningsih
Keyword(s):  
Maternal Age ◽  
World Health ◽  
Survey Method ◽  
P Value ◽  
Maternal Knowledge ◽  
Cross Sectional ◽  
Normal Delivery ◽  
Significance Level ◽  
Birth Canal ◽  
Maternal Parity

Childbirthis a processLabor of opening and depleting the cervix and the fetus down into the birth canal. Birth is a process in which the fetus and amniotic are pushed out through the birth canal. (Sarwono, 2008). According to the World Health Organization (WHO) estimates more than 585,000 mothers annually die during pregnancy or childbirth. Indonesia Health Demographic Survey (SDKI) Survey in 2012, Maternal Mortality Rate in Indonesia is still high at 359 per 100,000 live births. The purpose of this study is the knowledge of maternal knowledge, maternal age, and maternal parity associated with normal birth events at Palembang Bari Hospital 2017. This study used analytical survey method with cross sectional approach. The population in this study were all maternal mothers at the Palembang Bari Hospital in 2017. Sampling in the study was conducted non-randomly with the technique of "Accidental Sampling". Data analysis was done univariat and bivariate with Chi-Square statistical test with significance level α = 0,05. The result of this research shows that there is correlation between mother's knowledge with normal delivery incidence with p value 0,001, there is correlation between mother age with normal delivery incidence with p value 0,009, there is relation between mother parity with normal delivery incidence with p value 0,001. From result of this research hopes healthcare workers can improve normal delivery care services and more often to carry out maternal safety counseling.

Hubungan Religiusitas dengan Citra Tubuh pada Wanita Dewasa Awal

2018 ◽  
Vol 1 (1) ◽  
pp. 9-28
Author(s):  
Dessy Sumanty ◽  
Deden Sudirman ◽  
Diah Puspasari
Keyword(s):  
Body Image ◽  
Correlation Coefficient ◽  
Research Design ◽  
Calculation Result ◽  
The Body ◽  
Statistical Testing ◽  
P Value ◽  
Significance Level ◽  
Correlational Research

This research attempts to relate the body image phenomenon with the level of subject religiosity. This research used correlational research design that was involving 332 respondents. The statistical testing which is used to test the hypothesis Rank Spearman. The calculation result with the significance level of trust 95% (a = 0.05) show that the correlation coefficient is 0.083 and p-value is 0.129. It means that Ho is accepted and H1 is rejected. It can be concluded that there is no relationship between religiosity with body image.

Prediction of Haemoglobin Level by Some Probability Distribution

2020 ◽  
Vol 9 (1) ◽  
pp. 84-88
Author(s):  
Govinda Prasad Dhungana ◽  
Laxmi Prasad Sapkota
Keyword(s):  
Probability Distribution ◽  
Normal Distribution ◽  
Goodness Of Fit ◽  
Continuous Variable ◽  
Hemoglobin Level ◽  
Chi Square ◽  
Chi Square Test ◽  
Log Normal ◽  
Two Parameters ◽  
Best Fit

 Hemoglobin level is a continuous variable. So, it follows some theoretical probability distribution Normal, Log-normal, Gamma and Weibull distribution having two parameters. There is low variation in observed and expected frequency of Normal distribution in bar diagram. Similarly, calculated value of chi-square test (goodness of fit) is observed which is lower in Normal distribution. Furthermore, plot of PDFof Normal distribution covers larger area of histogram than all of other distribution. Hence Normal distribution is the best fit to predict the hemoglobin level in future.

Burden of Care Among Mothers Having Children with Congenital Heart Diseases

2020 ◽  
Vol 40 (2) ◽  
pp. 72-77
Author(s):  
Nita Sharma ◽  
Pratima Sharma ◽  
Tulashi Adhikari Mishra
Keyword(s):  
Heart Disease ◽  
Congenital Heart ◽  
Heart Diseases ◽  
Sampling Technique ◽  
Structured Interview ◽  
Health Condition ◽  
P Value ◽  
Burden Of Care ◽  
Cross Sectional ◽  
Significance Level

Introduction: Congenital Heart Disease (CHD) is a problem with structure and function of the heart that is present at birth.  Children with CHD require special care, treatment and follow up for a number of common conditions which may be quite straining to the care givers. The objective of the study was to find out the burden of care among mothers having children with CHD. Methods: This descriptive cross-sectional study was carried out in a cardiac centre of Nepal. A total of 95 mothers having children with CHD attending outpatient department of our institute were selected as the sample for the study using non-probability purposive sampling technique. A semi structured interview questionnaire consisting of the Modified Caregiver Strain Index was used to assess the burden of care among mothers having children with CHD. Frequency and percent were used to describe the variables and chi- square test at 0.05 significance level was used to analyse associations. Results: Most (77.9%) of the mothers were regularly strained to find that their children’s health condition was deteriorating due to CHD. Nearly half (44.2%) of the mothers always had financial constrain while giving care to the child, nearly half (40%) of the mothers had done emotional adjustments to take care of their children with CHD, another two-fifths (28.4%) of the mothers sometimes had disturbed sleep and almost half (46.3%) of the mothers were always upset due to some behaviour of their child with CHD. Half (50.5%) of the mothers had high level of burden of care. Statistically significant association were found between age of the mother and level of burden of care (p value = 0.05). Similarly, the type of family (p value = 0.005), age of the children (p value = 0.000) and type of CHD (p value = 0.002) were significantly associated with the level of burden of care among the mothers. Conclusion: The study concluded that mothers tend to feel less burden of care as the child grows older, mothers having children with cyanotic heart disease tend to experience more burden of care. Mothers of less than thirty years of age and living in a joint family also experience more burden of care.  

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