Statistical analysis of the seasonal variation in the twinning rate

Twin Research ◽  
1999 ◽  
Vol 2 (1) ◽  
pp. 22-29 ◽  
Author(s):  
Johan Fellman ◽  
Aldur W Eriksson
Keyword(s):  
Seasonal Variation ◽  
Seasonal Pattern ◽  
Summer Season ◽  
Seasonal Distribution ◽  
Alternative Methods ◽  
Total Birth ◽  
The Past ◽  
Different Populations ◽  
The 19Th Century ◽  
Trigonometric Regression

AbstractThere have been few secular analyses of the seasonal variation in human twinning and the results are conflicting. One reason for this is that the seasonal pattern of twinning varies in different populations and at different periods. Another reason is that the statistical methods used are different. The changing pattern of seasonal variation in twinning rates and total maternities in Denmark was traced for three periods (1855–69, 1870–94, and 1937–84). Two alternative methods of analysis are considered. The method of Walter and Elwood and a trigonometric regression model give closely similar results. The seasonal distribution of twin maternities for the periods in the 19th century showed highly significant departures. For both twin and general maternities, the main peaks can be seen from March to June and a local peak in September. During the spring– summer season the twinning rates were higher than the total birth rates, indicating a stronger seasonal variation for the twin maternities than for the general maternities. For 1937–84, there was a similar, but less accentuated, pattern. Studies of other populations are compared with the Danish results. The more accentuated seasonal variation of twinning in the past indicate that some factors in the past affected women during summer–autumn and around Christmas time, making them more fecund and particularly to be more prone to polyovulation and/or more able to complete a gestation with multiple embryos.

SEASONAL VARIATION OF BIRTHS IN RURAL WEST BENGAL: MAGNITUDE, DIRECTION AND CORRELATES

2000 ◽  
Vol 32 (4) ◽  
pp. 443-458 ◽  
Author(s):  
UMA CHATTERJEE ◽  
RAJIB ACHARYA
Keyword(s):  
Seasonal Variation ◽  
West Bengal ◽  
Seasonal Pattern ◽  
Family Health ◽  
Atmospheric Temperature ◽  
Marriage Pattern ◽  
Study Population ◽  
Time Series Analyses ◽  
Trigonometric Regression ◽  
And Child Health

This paper examines seasonal variation of births in a rural community of West Bengal, India, by exploring data from the 1992–93 National Family Health Survey. Suitable time series analyses were used to determine the seasonal pattern of births and to estimate peaks. The trigonometric regression technique was used to carry out this objective. The study attempted to link the results of the regression analysis to the atmospheric temperature of the region during 1987–91, the distribution of respondents’ husbands’ occupations and the marriage pattern of the community. It was found that, in the study population, conceptions were numerous in the first quarter of a calendar year and the distribution of conceptions over calendar months was negatively associated with the average monthly temperature. In addition, the marriage pattern of the community and the occupational distribution of the fathers also had a significant effect on the distribution of births over calendar months. It is hoped that the findings will boost the development of needs-based maternal and child health (MCH) and family planning programmes in the community.

Facts and Myths about Seasonal Variation in Suicide

2007 ◽  
Vol 100 (3) ◽  
pp. 810-814 ◽  
Author(s):  
Martin Voracek ◽  
Ulrich S. Tran ◽  
Gernot Sonneck
Keyword(s):  
Seasonal Variation ◽  
Northern Hemisphere ◽  
Seasonal Pattern ◽  
Early Summer ◽  
Seasonal Distribution ◽  
Late Spring ◽  
Early Winter ◽  
Late Autumn ◽  
Everyday Reasoning

The prevalence of suicide presents a universal seasonal pattern. In the Northern hemisphere, suicides peak during spring and early summer and the trough occurs during winter. This peculiar pattern might be counterintuitive for everyday reasoning. Data from 1,093 medical and psychology undergraduates from Austria (382 men and 711 women; M age 25.0 yr., SD = 6.6) indicated an almost perfectly reversed pattern of beliefs about suicide seasonality compared with the actual seasonal distribution. The vast majority of respondents believed the peak to be located in late autumn and early winter and the trough occurring in late spring and the summer months. Implications for education and practice are discussed.

Investigating Applicability of the Meshfree Method to the Structural Analysis of Tires

2012 ◽  
Vol 40 (2) ◽  
pp. 60-82
Author(s):  
Ken Ishihara ◽  
Takehiro Noda ◽  
Hiroyuki Sakurai
Keyword(s):  
Meshfree Method ◽  
Alternative Methods ◽  
The Finite Element Method ◽  
Tire Industry ◽  
Academic Communities ◽  
The Past ◽  
New Methodologies ◽  
Tire Modeling ◽  
Point Data ◽  
Conducting Research

ABSTRACT In contrast to the finite element method (FEM), which is widely used in the tire industry nowadays, some alternative methods have been proposed by academic communities over the past decade or so. The meshfree method is one of those new methodologies. Originally intended to remove the burden of creating the mesh that is inherent in FEM, the meshfree method relies on the point data rather than the mesh, which makes it much easier to discretize the geometry. In addition to those modeling issues, it has been found that the meshfree method has several advantages over FEM in handling geometrical nonlinearities, continuities, and so forth. In accordance with those emerging possibilities, the authors have been conducting research on the matter. This article describes the results of the authors' preliminary research on the applicability of the meshfree method to tire analyses, which include the theoretical outline, the strategy of tire modeling, numerical results, comparisons with results of FEM, and conclusions.

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping data

2010 ◽  
Vol 27 (2) ◽  
pp. 85-91 ◽  
Author(s):  
Martin Šlachta ◽  
Jan Frelich ◽  
Tomáš Tonka
Keyword(s):  
Seasonal Variation ◽  
Spatial Variation ◽  
Dry Weight ◽  
Seasonal Distribution ◽  
The Other ◽  
Pitfall Trapping ◽  
Other Hand ◽  
Nested Anova ◽  
Species Groups ◽  
Dung Decomposition

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping dataAn analysis of data on the dry weight biomass of coprophagous beetles in standardized dung (4.5 l) was conducted in order to characterize the spatial and the seasonal distribution of the beetles' biomass in cattle pastures and to elucidate their function in dung decomposition. Nested Anova with factors of farm, site (nested in farm), seasonal period and year was used to evaluate the effect of these factors on the biomass of four functional species groups: the dung dwellers ofScarabaeidae(subfamilyAphodiinae), the dung dwellers ofHydrophilidae, the small tunnellers ofScarabaeidae(subfamilyCoprinae) and the large tunnellers ofGeotrupidae. The spatial variation of biomass (between the sites and the farms) was insignificant (P>0.05) in the two dung-dweller groups and in the large-tunnellers group. On the other hand, a significant (P<0.05) seasonal variation of biomass was found in all but the large tunneller group. In dung dwellers, the spring biomass was formed mainly by two species,Aphodius prodromusandA. sphacelatus. In summer, most of the biomass was accounted for bySphaeridium lunatum, S. scarabaeoidesandA. rufipes. In the two tunneller groups,Onthophagus fracticornis, Geotrupes stercorariusandG. spinigerformed a majority of the biomass in dung.

Colchicum autumnale (Colchicaceae) w okolicach Krakowa – dawne i obecne rozmieszczenie

2019 ◽  
pp. 15-27
Author(s):  
Magdalena Zarzyka-Ryszka
Keyword(s):  
Adjacent Area ◽  
Colchicum Autumnale ◽  
The Past ◽  
The North ◽  
North Eastern ◽  
New Localities ◽  
Present Distribution ◽  
The 19Th Century ◽  
North Eastern Part

The paper describes the past and present distribution of Colchicum autumnale in the vicinity of Cracow, highlights the role of Stanisław Dembosz (who published the first locality of C. autumnale near Igołomia in 1841). Gives information about the occurrence of C. autumnale in Krzeszowice in the 19th century (reported by Bronisław Gustawicz), presents new localities noted in 2012–2014 in meadows in the north-eastern part of the Puszcza Niepołomicka forest and adjacent area (between the Vistula and Raba rivers), and gives a locality found in Cracow in 2005 (no longer extant).

Statehood and the State-Like in International Law

2019 ◽  
Author(s):  
Rowan Nicholson
Keyword(s):  
Hong Kong ◽  
International Law ◽  
The State ◽  
Alternative Methods ◽  
Important Conclusion ◽  
Territorial Integrity ◽  
The Past ◽  
Imperial China ◽  
Peremptory Norms ◽  
Legal Sense

If the term were given its literal meaning, international law would be law between ‘nations’. It is often described instead as being primarily between states. But this conceals the diversity of the nations or state-like entities that have personality in international law or that have had it historically. This book reconceptualizes statehood by positioning it within that wider family of state-like entities. An important conclusion of the book is that states themselves have diverse legal underpinnings. Practice in cases such as Somalia and broader principles indicate that international law provides not one but two alternative methods of qualifying as a state: subject to exceptions connected with territorial integrity and peremptory norms, an entity can be a state either on the ground that it meets criteria of effectiveness or on the ground that it is recognized by all other states. Another conclusion is that states, in the strict legal sense in which the word is used today, have never been the only state-like entities with personality in international law. Others from the past and present include imperial China in the period when it was unreceptive to Western norms; pre-colonial African chiefdoms; ‘states-in-context’, an example of which may be Palestine, which have the attributes of statehood relative to states that recognize them; and entities such as Hong Kong.

scholarly journals 3D Insights into the Effects of Captivity on Wolf Mastication and Their Tooth Marks; Implications in Ecological Studies of Both the Past and Present

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2323
Author(s):  
Lloyd A. Courtenay ◽  
Darío Herranz-Rodrigo ◽  
José Yravedra ◽  
José Mª Vázquez-Rodríguez ◽  
Rosa Huguet ◽  
...  
Keyword(s):  
Data Science ◽  
Surface Modifications ◽  
Human Populations ◽  
Ecological Studies ◽  
The Past ◽  
Carnivore Species ◽  
Different Populations ◽  
Complex Relationships ◽  
As Stress ◽  
Tooth Marks

Human populations have been known to develop complex relationships with large carnivore species throughout time, with evidence of both competition and collaboration to obtain resources throughout the Pleistocene. From this perspective, many archaeological and palaeontological sites present evidence of carnivore modifications to bone. In response to this, specialists in the study of microscopic bone surface modifications have resorted to the use of 3D modeling and data science techniques for the inspection of these elements, reaching novel limits for the discerning of carnivore agencies. The present research analyzes the tooth mark variability produced by multiple Iberian wolf individuals, with the aim of studying how captivity may affect the nature of tooth marks left on bone. In addition to this, four different populations of both wild and captive Iberian wolves are also compared for a more in-depth comparison of intra-species variability. This research statistically shows that large canid tooth pits are the least affected by captivity, while tooth scores appear more superficial when produced by captive wolves. The superficial nature of captive wolf tooth scores is additionally seen to correlate with other metric features, thus influencing overall mark morphologies. In light of this, the present study opens a new dialogue on the reasons behind this, advising caution when using tooth scores for carnivore identification and contemplating how elements such as stress may be affecting the wolves under study.

Seasonal variation in births in rural East Pakistan

1972 ◽  
Vol 4 (1) ◽  
pp. 107-116 ◽  
Author(s):  
John Stoeckel ◽  
A. K. M. Alauddin Choudhury
Keyword(s):  
Seasonal Variation ◽  
Social Factors ◽  
Seasonal Pattern ◽  
Seasonal Patterns ◽  
First Order ◽  
Monthly Temperature ◽  
Monthly Distribution ◽  
Number Of Births

SummaryAn analysis of the monthly distribution of births in two areas of Matlab Thana, East Pakistan, indicates that there is a seasonal variation in births different from what would be expected by chance. The highest proportion of births occur in the last three months of a year and the lowest proportion between May and July. Investigation into some of the environmental and social factors which might contribute to the seasonal pattern revealed the following: mean minimum monthly temperature 9 months before birth was inversely related to the number of births; all occupations had seasonal patterns different from what would be expected by chance and the business and mill-and-office occupations had distributions significantly different from each other; the distribution of births for all pregnancy orders was different from chance and the distribution for first order pregnancies was significantly different from those for third and fourth or higher orders.

scholarly journals Increase in searches for erectile dysfunction during winter: seasonal variation evidence from Google Trends in the United States

2021 ◽  
Author(s):  
Belén Mora Garijo ◽  
Jonathan E. Katz ◽  
Aubrey Greer ◽  
Mia Gonzalgo ◽  
Alejandro García López ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
United States ◽  
Erectile Dysfunction ◽  
Seasonal Variation ◽  
Kidney Stones ◽  
Seasonal Pattern ◽  
The United States ◽  
Google Trends ◽  
Internet Search ◽  
Search Volume

AbstractSeveral diseases associated with erectile dysfunction (ED), such as type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD), are known to have seasonal variation, with increased incidence during winter months. However, no literature exists on whether this chronological-seasonal evolution is also present within ED symptomatology. We hypothesized ED would follow the seasonal pattern of its lifestyle-influenced comorbid conditions and exhibit increased incidence during winter months. In order to investigate the seasonal variation of ED in the United States between 2009 and 2019, Internet search query data were obtained using Google Trends. Normalized search volume was determined during the winter and summer seasons for ED, other diseases known to be significantly associated with ED (T2DM and CAD), kidney stones (positive control), and prostate cancer (negative control). There were significantly more internet search queries for ED during the winter than during the summer (p = 0.001). CAD and T2DM also had significantly increased search volume during winter months compared to summer months (p < 0.001 and p = 0.011, respectively). By contrast, searches for kidney stones were significantly increased in the summer than in the winter (p < 0.001). There was no significant seasonal variation in the relative search frequency for prostate cancer (p = 0.75). In conclusion, Google Trends internet search data across a ten-year period in the United States suggested a seasonal variation in ED, which implies an increase in ED during winter. This novel finding in ED epidemiology may help increase awareness of ED’s associated lifestyle risk factors, which may facilitate early medical evaluation and treatment for those at risk of both ED and cardiovascular disease.

Protozoan infection in archaeological material

1970 ◽  
Vol 80 (1) ◽  
Author(s):  
Marcelo Luiz Carvalho Gonçalves ◽  
Cassius Schnell ◽  
Luciana Sianto ◽  
Francoise Bouchet ◽  
Mathieu Le Bailly ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
19Th Century ◽  
Intestinal Parasites ◽  
Giardia Duodenalis ◽  
Human Feces ◽  
Archaeological Material ◽  
The Past ◽  
Protozoan Infection ◽  
Protein Molecules ◽  
The 19Th Century

The identification of parasites in ancient human feces is compromised by differential preservation of identifiable parasite structures. However, protein molecules can survive the damage of the environment. It was possible to detected antigen of Entamoeba histolytica and Giardia duodenalis in historic and prehistoric human fecal remains using two enzyme immunoassay (ELISA) kits with monoclonal antibodies specific for E. histolytica and G. duodenalis, respectively. Specimens of desiccated feces and ancient latrine sediment from the New and the Old World were examined. The ELISA detected E. histolytica antigen in samples from Argentina, USA, France, Belgium, and Switzerland, dated to about 5300 years BP to the 19th Century AD. G. duodenalis antigen was detected in samples from USA, Belgium, and Germany, dated to about 1200 AD, 1600 AD, and 1700 AD. The detection of protozoan antigen using immunoassays is a reliable tool for the study of intestinal parasites in the past.

Sign in / Sign up

Export Citation Format

Share Document