VARIATIONS IN THE INTRINSIC STRENGTH OF THE 1956 QUADRANTID METEOR SHOWER

1957 ◽  
Vol 35 (6) ◽  
pp. 703-711 ◽  
Author(s):  
C. O. Hines ◽  
E. L. Vogan
Keyword(s):  
Incidence Rate ◽  
Detection Rate ◽  
Meteor Shower ◽  
New Technique ◽  
Occurrence Rate ◽  
Meteor Stream ◽  
Forward Scatter ◽  
Scatter Theory ◽  
Intrinsic Strength

The occurrence rate of meteoric signals, detected on a V.H.F. forward-scatter path, is analyzed for the time of the 1956 Quadrantid shower. The detection rate of the shower meteors is converted to an incidence rate, by use of the appropriate forward-scatter theory. The variation in the intrinsic strength of the shower is thereby determined, on an hour-to-hour basis, and it is compared with variations which have been obtained in other years by other methods. The comparison reveals a distinct secular shifting of the orbit of the Quadrantid meteor stream. It also illustrates the marked advantage of the new technique in assessing variations in the strengths of short-lived showers.

scholarly journals 1. The radar meteor echo (survey paper)

1968 ◽  
Vol 33 ◽  
pp. 3-13 ◽  
Author(s):  
P. M. Millman
Keyword(s):  
World War Ii ◽  
Meteor Shower ◽  
New Technique ◽  
World War ◽  
The Real ◽  
Survey Paper ◽  
Radar Meteor

From about 1930 on various scattered notes appeared from time to time, pointing out certain radio effects that probably resulted from meteors. However, the real birth of the serious observation of meteors by radio took place on the night of October 9–10, 1946, when the Giacobinid meteor shower returned in considerable strength. This was observed with re-built World-War II radar equipment in both England and the U.S.A., and the results achieved left no doubt concerning the value of the new technique in meteoric astronomy. Figure 1 illustrates two historic examples of meteor echoes recorded in England on this occasion (Appleton and Naismith, 1947; Hey et al., 1947). Since this date the field has expanded rapidly. Useful general summaries may be found in a number of monographs, e.g., Lovell (1954), McKinley (1961).

scholarly journals Smoking habits and detection rate of unruptured intracranial aneurysms and incidence rate of subarachnoid haemorrhage in Norway between 2008 and 2015

2020 ◽  
Vol 162 (12) ◽  
pp. 3161-3165
Author(s):  
Paulina Majewska ◽  
Sasha Gulati ◽  
Lise Øie ◽  
Øyvind Salvesen ◽  
Tomm B. Müller ◽  
...  
Keyword(s):  
Subarachnoid Haemorrhage ◽  
Incidence Rate ◽  
Intracranial Aneurysms ◽  
Detection Rate ◽  
Hazard Ratio ◽  
Smoking Habits ◽  
Daily Smoking ◽  
Aneurysmal Subarachnoid Haemorrhage ◽  
Age Group ◽  
Unruptured Intracranial Aneurysms

Abstract Objective The aim of this study was to investigate the detection rate of unruptured intracranial aneurysms (UIAs) and incidence of aneurysmal subarachnoid haemorrhage (SAH) in relation to the rapidly changing smoking rates in Norway between 2008 and 2015. Methods The registry-based study included all patients (≥ 16 years old) admitted to a hospital in Norway between 2008 and 2015 with a primary diagnosis of aneurysmal SAH or an outpatient diagnosis of UIAs. Age group–specific and total detection rate of UIAs and incidence rate of SAH over the years were calculated. Age group–specific data on smoking habits was retrieved from a national annual survey representative of the whole Norwegian population. Results The rate of daily smokers decreased by 48% between 2008 and 2015. The detection rate of UIAs decreased by 47% from 17.3 in 2008 to 9.3 per 100,000 persons in 2015, and the incidence of SAH decreased by 30% from 11.3 in 2008 to 7.9 per 100,000 persons in 2015. The average annual decline in prevalence of daily smoking, UIA detection rate, and SAH incidence was 6.9%, 6.7%, and 4.3% per year, respectively. Multinomial logistic regression analyses revealed that the correlation between the decline in estimated daily smoking rates and decline in detection rate of UIAs (hazard ratio 52.5 CI = (14.9,∞), p < 0.00001) and incidence of SAH (hazard ratio 11.8 CI=(5.6,32.5), p < 0.00001) are statistically significant. The association is particularly strong in young and middle-aged cohorts (< 66 years old). Conclusion It is likely that reducing cigarette smoking on a population-based level strongly reduces the rates of UIAs and SAH.

scholarly journals Aspirin Decreases Hepatocellular Carcinoma Risk in Hepatitis C Virus Carriers: A Nationwide Cohort Study

2019 ◽  
Author(s):  
Yen-Hsiang Liao ◽  
Wen-Lin Hsu ◽  
Tzu-Hwei Wang ◽  
Chen-Ta Wu ◽  
Sheng-Yao Huang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cohort Study ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Propensity Score ◽  
Propensity Score Matching ◽  
Incidence Rate ◽  
Occurrence Rate ◽  
Control Group ◽  
Cancer Occurrence

Abstract Background Aspirin lowered some cancer occurrence rate, through the inhibition of the cyclooxygenase enzyme. The association of aspirin-use and hepatocellular carcinoma (HCC) occurrence rate in hepatitis B virus (HBV) carriers is well known. However, the association in hepatitis C virus (HCV) carriers is not known. Our purpose is comparing the HCC occurrence rate in HCV carriers with or without Aspirin treatment. Methods In this retrospective cohort study, the participants were ones newly-diagnosed with HCV from 2000 to 2012 in Taiwan. These HCV carriers with aspirin treatment were defined as the control group, whereas those without aspirin were defined as a compared cohort. We used a 1:1 propensity score matching by age, sex, comorbidities, drugs, diagnosis year and index year with covariate assessment. Results Our study sample consisted of 2980 aspirin-treated HCV carriers and 7771 non-aspirin-treated HCV carriers. After propensity score matching, each cohort consisted of 1911 HCV carriers. The adjusted hazard ratio (aHR) of HCC incidence in aspirin users (aHR=0.56, 95% CI=0.43-0.72, p < 0.001 ) was significantly lower than that in non-aspirin users. The Kaplan-Meier curves show that among the HCV carriers, aspirin users had a lower cumulative incidence rate of HCC in the first 10-year aspirin treatment course ( p < 0.0001 ). Conclusions The HCC incidence rate was lower in the aspirin users than non- aspirin users among HCV carriers, supporting the aspirin effect may be acting through inhibition of the cyclooxygenase enzyme pathway. Moreover, the patients got HCC protection by aspirin within 1-year treatment course and had best HCC prevention during 1- to 2-year aspirin treatment course. We encourage aspirin treatment to prevent HCC in HCV carriers.

scholarly journals Impact of treatment with anti-parasitic (Ivermectin) during prepartum period on mastitis and postpartum reproductive efficiency measurements in Egyptian Baladi cows

2021 ◽  
Author(s):  
Ahmed Ismail Damarany
Keyword(s):  
Incidence Rate ◽  
Reproductive Performance ◽  
The Other ◽  
Occurrence Rate ◽  
Reproductive Efficiency ◽  
Control Group ◽  
Current Investigation ◽  
Live Body Weight ◽  
Effect Of Treatment ◽  
Incident Rate

Abstract The current investigation was designed to determine the effect of treatment with anti-parasites (Ivermectin) on mastitis and postpartum reproductive efficiency measurements in Egyptian Baladi cows. Twenty-four of the cows included in this study were split into two groups. The first group (n = 12 cows) was injected two months prepartum with two doses (15 days inter-treatment) of IVOMEC® Plus solution subcutaneously behind the shoulder, 1ml/50kg live body weight as prescribed by the manufacturer, whilst the other group (n = 12 cows) was used as a control group. The present results revealed that the incident rate of mastitis in treated cows’ group was significantly (P < 0.05) lower (16.7%) than control cows’ group (41.7%). The conception rate in treated cows’ group was significantly (P < 0.05) higher (66.7%) compared with (33.3%) in control group. The time from calving to conception in treated cows was significantly (P < 0.05) lower 86.5 ± 11.4 days compared to 123.3 ± 13.2 days in the control group. The occurrence rate of anestrous cases was significantly (P < 0.05) lower (8.3%) in treated cows than (control group) (25%). In conclusion, the current study indicates there is an association between treated cows with anti-parasites (Ivermectin) two months prepartum and incidence rate of mastitis addition an improvement in the reproductive performance in treated cows relative to untreated cows. Therefore, the current study recommends the herdsmen treats their cows with anti-parasites (Ivermectin) during the prepartum period for less mastitis incidence rate and better reproductive efficiency.

scholarly journals 44. Investigation of perturbed motion of the leonid meteor stream

1968 ◽  
Vol 33 ◽  
pp. 449-475 ◽  
Author(s):  
E. I. Kazimirčak-Polonskaja ◽  
N. A. Beljaev ◽  
I. S. Astapovič ◽  
A. K. Terenteva
Keyword(s):  
Maximum Activity ◽  
Meteor Shower ◽  
Meteor Stream ◽  
Outer Planets ◽  
The Earth ◽  
Meteor Body ◽  
Action At A Distance ◽  
Last 300 Years ◽  
The Times ◽  
Made In

The investigation is based on a system of elements, obtained from the best observations made in England during the maximum of the meteor shower 1866. This system represents the most probable orbit of that part of the stream, which passed perihelion during the years 1864–67 and was later given the name of Ortho-Leonids. Seventeen points (meteor groups) have been chosen on this orbit, and differential equations of their motion have been integrated on the electronic computer BESM-2 by Cowell's method of quadratures, taking account of perturbations from eight planets (Venus–Pluto), with a variable step from 0·001 to 40 days and taking account of differences through to the 4th order. The motions of two groups (XI and XII) have been investigated in an interval of 300 years (1700–2000), and the motions of the rest of the groups for a space of 135 years (1866–2000). All the close approaches of these groups to the Earth, Jupiter, Saturn and Uranus have been determined. The results of integration are given in the tables, which clearly represent the evolution of the orbit of every group. It has been found that the basic factors determining the evolution of separate groups, and of the stream as a whole, are the close approaches to the outer planets. The perturbations by these planets, especially by Jupiter and Saturn, determine the conditions for an encounter of the meteor groups with the Earth, and cause a change in the activity of the Leonid shower at different apparitions. Apparitions of the Leonids have been investigated for the last millennium, and in more detail for the last 180 years. It has been stated that the orbit of the Ortho-Leonid stream remained stable over the interval of 1000 years; its stability has been confirmed by calculations during the last 300 years, and the limits of changes of its elements have been computed. The perturbing influence of the Earth on the motion of meteor bodies in its sphere of action has been investigated. It turns out that at exceptionally deep penetrations of meteor bodies into this sphere of action, at a distance of some 1000 km from the Earth, its perturbations can essentially transform the orbit of a meteor body, e.g. reduce its period of revolution by some years, and materially change the eccentricity of the orbit, its inclination, etc. Conditions for an encounter of the stream with the Earth in the period 1898–2000 have been clarified, and forecasts have been made for the times of maximum activity of the shower in the years 1966–68. In 1967 the maximum activity of the Leonids is predicted to occur from November 17, 18h to November 18, 1h UT.

scholarly journals Analysis of disease spectrum of corporate executives after physical examination

2011 ◽  
Vol 1 (3) ◽  
pp. 166-170
Author(s):  
Li Qing ◽  
Guo Huailan ◽  
Chen Jin ◽  
Chen Jianhua ◽  
Yanjun Zeng
Keyword(s):  
Physical Examination ◽  
Incidence Rate ◽  
Prevalence Rate ◽  
Detection Rate ◽  
Metabolic Diseases ◽  
High Risk Group ◽  
Mineral Density ◽  
Cross Sectional ◽  
Corporate Executives ◽  
Disease Spectrum

Introduction: To find out the disease spectrum of corporate executives and screen the common chronic diseases.Methods: The physical examination data of corporate executives were collected to carry out cross-sectional study.Results: Among 231 subjects, there were one hundred and ninety four males, which made up 85.3%, and thirty seven females, which made up 14.7%. The detection rate of chronic diseases in corporate executive was high. Specifically, the incidence rate of blood viscosity rise was 87.8%; the incidence rate of blood lipid rise was 79.5%; the incidence rate of obesity and overweight was 76.7%; the infection rate of Helicobacter pylori was 55.7%; the prevalence rate of fatty liver was 52.1%; the prevalence rate of kidney stones was 43.5%; the incidence of abnormal pancreatic echo was 52.3%; the incidence rate of abnormal TCD was 66.2%; the detection rate of coarse gallbladder wall was 35.5%. The prevalence rate of bone mineral density reduction was 39.6%; the detection rate of reduction of diastolic function of left ventricle was 37.5%; the incidence rate of raised serum uric acid was 28.6%; the incidence rate of blood glucose going up was 22%; the incidence rate of liver cyst was 19.5%. The prevalence rate of blood LDL rise was 23.9%; the prevalence rate of abnormal thyroid was 21.3%; the incidence rate of arteriosclerosis was 17.5%; the prevalence rate of hypertension was 17.4%.Conclusion: The corporate executives are high risk group of common metabolic diseases and cardiovascular and cerebrovascular diseases. Therefore, screening should be strengthened for them.

scholarly journals The Sextanid Meteor Stream

1964 ◽  
Vol 17 (1) ◽  
pp. 158 ◽  
Author(s):  
CS Nilsson
Keyword(s):  
Meteor Shower ◽  
Peak Activity ◽  
Meteor Stream ◽  
Time Plot

The Sextanid meteor shower was first reported by Weiss (1960), who matched theoretical envelopes to the echo range-time plot from a directive radar rate equipment to find the radiant = 155�8�, S = 0�1O�. The peak activity persisted from September 29 to October 3, but was noticeable only in 1957. No trace of activity due to this shower could be found in previous surveys.

Sign in / Sign up

Export Citation Format

Share Document