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Sample records for high fertility populations

  1. Fertility and Population Policy

    OpenAIRE

    Ouedraogo, Abdoulaye; Tosun, Mehmet S.; Yang, Jingjing

    2018-01-01

    There have been significant changes in both the fertility rates and fertility perception since 1970s. In this paper, we examine the relationship between government policies towards fertility and the fertility trends. Total fertility rate, defined as the number of children per woman, is used as the main fertility trend variable. We use panel data from the United Nations World Population Policies database, and the World Bank World Development Indicators for the period 1976 through 2013. We find...

  2. Personality and reproductive success in a high-fertility human population.

    Science.gov (United States)

    Alvergne, Alexandra; Jokela, Markus; Lummaa, Virpi

    2010-06-29

    The existence of interindividual differences in personality traits poses a challenge to evolutionary thinking. Although research on the ultimate consequences of personality differences in nonhuman animals has recently undergone a surge of interest, our understanding of whether and how personality influences reproductive decisions in humans has remained limited and informed primarily by modern societies with low mortality-fertility schedules. Taking an evolutionary approach, we use data from a contemporary polygynous high-fertility human population living in rural Senegal to investigate whether personality dimensions are associated with key life-history traits in humans, i.e., quantity and quality of offspring. We show that personality dimensions predict reproductive success differently in men and women in such societies and, in women, are associated with a trade-off between offspring quantity and quality. In women, neuroticism positively predicts the number of children, both between and within polygynous families. Furthermore, within the low social class, offspring quality (i.e., child nutritional status) decreases with a woman's neuroticism, indicating a reproductive trade-off between offspring quantity and quality. Consistent with this, maximal fitness is achieved by women at an intermediate neuroticism level. In men, extraversion was found to be a strong predictor of high social class and polygyny, with extraverted men producing more offspring than their introverted counterparts. These results have implications for the consideration of alternative adaptive hypotheses in the current debate on the maintenance of personality differences and the role of individual factors in fertility patterns in contemporary humans.

  3. Global fertility and population trends.

    Science.gov (United States)

    Bongaarts, John

    2015-01-01

    Over the past several decades, the world and most countries have undergone unprecedented demographic change. The most obvious example of this change is the rise in human numbers, and there are also important trends in fertility, family structure, mortality, migration, urbanization, and population aging. This paper summarizes past trends and projections in fertility and population. After reaching 2.5 billion in 1950, the world population grew rapidly to 7.2 billion in 2013 and the projections expect this total to be 10.9 billion by 2100. World regions differ widely in their demographic trends, with rapid population growth and high fertility continuing in the poorest countries, particularly in sub-Saharan Africa, while population decline, population aging, and very low fertility are now a key concern in many developed countries. These trends have important implications for human welfare and are of interest to policy makers. The conclusion comments briefly on policy options to address these adverse trends. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. Infant and fetal mortality among a high fertility and mortality population in the Bolivian Amazon.

    Science.gov (United States)

    Gurven, Michael

    2012-12-01

    Indigenous populations experience higher rates of poverty, disease and mortality than non-indigenous populations. To gauge current and future risks among Tsimane Amerindians of Bolivia, I assess mortality rates and growth early in life, and changes in risks due to modernization, based on demographic interviews conducted Sept. 2002-July 2005. Tsimane have high fertility (total fertility rate = 9) and infant mortality (13%). Infections are the leading cause of infant death (55%). Infant mortality is greatest among women who are young, monolingual, space births close together, and live far from town. Infant mortality declined during the period 1990-2002, and a higher rate of reported miscarriages occurred during the 1950-1989 period. Infant deaths are more frequent among those born in the wet season. Infant stunting, underweight and wasting are common (34%, 15% and 12%, respectively) and greatest for low-weight mothers and high parity infants. Regression analysis of infant growth shows minimal regional differences in anthropometrics but greater stunting and underweight during the first two years of life. Males are more likely to be underweight, wasted, and spontaneously aborted. Whereas morbidity and stunting are prevalent in infancy, greater food availability later in life has not yet resulted in chronic diseases (e.g. hypertension, atherosclerosis and diabetes) in adulthood due to the relatively traditional Tsimane lifestyle. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Infant and fetal mortality among a high fertility and mortality population in the Bolivian Amazon

    Science.gov (United States)

    Gurven, Michael

    2012-01-01

    Indigenous populations experience higher rates of poverty, disease and mortality than non-indigenous populations. To gauge current and future risks among Tsimane Amerindians of Bolivia, I assess mortality rates and growth early in life, and changes in risks due to modernization, based on demographic interviews conducted Sept. 2002–July 2005. Tsimane have high fertility (Total Fertility Rate = 9) and infant mortality (13%). Infections are the leading cause of infant death (55%). Infant mortality is greatest among women who are young, monolingual, space births close together, and live far from town. Infant mortality declined during the period 1990–2002, and a higher rate of reported miscarriages occurred during the 1950–1989 period. Infant deaths are more frequent among those born in the wet season. Infant stunting, underweight and wasting are common (34%, 15% and 12%, respectively) and greatest for low-weight mothers and high parity infants. Regression analysis of infant growth shows minimal regional differences in anthropometrics but greater stunting and underweight during the first two years of life. Males are more likely to be underweight, wasted, and spontaneously aborted. Whereas morbidity and stunting are prevalent in infancy, greater food availability later in life has not yet resulted in chronic diseases (e.g. hypertension, atherosclerosis and diabetes) in adulthood due to the relatively traditional Tsimane lifestyle. PMID:23092724

  6. Past, Present and Future: Immigration, High Fertility Fuel State's Population Growth.

    Science.gov (United States)

    Clark, William A. V.

    2000-01-01

    Presents demographic information on California's increasing population and ethnic diversity. Describes age pyramids and fertility rates by ethnic group, indicating that Asians and Hispanics will comprise over two-thirds of the state's population by 2030. Discusses implications for education, teenage pregnancy, political representation, prenatal…

  7. Tunisia: high fertility stalls development.

    Science.gov (United States)

    Barberis, M

    1985-01-01

    Despite government policy enacted in 1964 to reduce fertility in order to hasten socioeconomic progress, population pressures continue to impair development in Tunisia. The birth rate fell 20% over the last 2 decades, but this accomplishment has been outweighed by a 50% decline in mortality rates. As a result, the rate of natural population increase has remained relatively constant at 2.5%/year. The initial decline in fertility that followed introduction of the national family planning program appears to have reached a plateau, explained in part by the resurgence of conservatism and religious fundamentalism and the consequent emphasis on women's childbearing roles. Unemployment in rural areas has led to widespread migration and unemployment is as high as 20% in the nonagricultural sector. Many young Tunisians lack adequate educational preparation to enter the labor force; in 1982, 27% of new job entrants could not read or write. The government's plan to decentralize development to stabilize population and achieve equilibrium between regions has been thwarted by the pace of population growth and limited resources. The rural regions where population is increasing the fastest are also the most difficult to reach with family planning programs. On the other hand, there have been some successes in this area when services have been adapted to the lifestyle and traditions of those in these isolated rural villages.

  8. Reproductive history and breast cancer in a population of high fertility, Costa Rica, 1984-85

    OpenAIRE

    Rosero-Bixby, Luis; Oberle, Mark W.; Lee, Nancy C.

    1987-01-01

    Artículo científico -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 1987 The relationship between breast cancer and women's reproductive history in Costa Rica was analyzed using logistic regression methods on data from 171 breast cancer cases and 826 population-based controls aged 25–58 years. The risk of breast cancer in nulliparous women under age 45 was 3 times that for parous women in the same age group. Women over 44 years of age with a parity greater than 4 had a...

  9. Population pressure and fertility in pre-transition Thailand.

    Science.gov (United States)

    VanLandingham, M; Hirschman, C

    2001-11-01

    Before the demographic transition in Thailand, fertility was high, but not uniformly so. As in other pre-transition settings, Thai fertility responded to pressures and opportunities created by socioeconomic structure and land availability. Drawing upon provincial data from the 1947 and 1960 censuses of Thailand, we find a strong 'frontier effect' on Thai fertility in the 1950s. Fertility was higher in sparsely settled frontier provinces and lower in provinces with higher population density relative to cultivatable land. This finding is robust and holds up with controls for agricultural employment, land quality, and the sex ratio (an indicator of sex-selective migration). The effect of population pressure lowers the likelihood of marriage and of marital fertility. The findings from Thailand are consistent with the research of Easterlin on the nineteenth century United States and with other pre-transition societies. We suggest how demographic transition theory might be broadened to include fertility dynamics in pre-transition societies.

  10. Birth Order and Sibling Sex Ratio in a Population with High Fertility: Are Turkish Male to Female Transsexuals Different?

    Science.gov (United States)

    Bozkurt, Ali; Bozkurt, Ozlem Hekim; Sonmez, Ipek

    2015-07-01

    Western studies have consistently found that androphilic (sexually attracted to men) male-to-female transsexuals have a later birth order and a relative excess of brothers compared with appropriate control participants. However, non-Western studies on birth order and sibling sex ratio in androphilic males (transsexual or non-transsexual) are rare. The objective of the study was to test the hypothesis that androphilic male-to-female transsexuals have a late birth order and a relative excess of brothers in a non-Western culture with a higher fertility rate. The participants were 60 androphilic male-to-female transsexuals and 61 male heterosexual controls. The transsexual participants had significantly more older brothers than the control participants, but the groups did not differ in their numbers of older sisters, younger brothers, or younger sisters. The foregoing pattern is usually referred to as the "fraternal birth order effect." Slater's and Berglin's Indexes both showed that the mean birth order of the control participants was very close to that expected from a random sample drawn from a demographically stable population whereas the mean birth order of the transsexual participants was later. A measure of sibship composition, brothers/all siblings, showed that the transsexual group had a higher proportion of male siblings compared with the control group. In conclusion, the present study found that Turkish androphilic male-to-female transsexuals show the same high fraternal birth order that has been found in comparable androphilic samples in Western Europe, North America, and the South Pacific, which suggests a common underlying biological causal mechanism.

  11. [Fertility change in Mexico and the politics of population].

    Science.gov (United States)

    Zavala De Cosio, M E

    1993-01-01

    This introduction to a detailed study of fertility change in Mexico assesses the available fertility data and describes the sources used, traces the beginning and course of the demographic transition in Mexico, and describes the work. Mexico's demographic transition began around 1930 with the acceleration of mortality decline. The considerable time lag between the mortality decline and the beginning of the fertility decline resulted in a period of very rapid growth. Between 1955 and 1975, the growth rate exceeded 3% annually. The start of the fertility decline dated to about 1970, the time of a major reform of population policy and creation of institutions to reduce growth. But the fertility decline was not solely the result of population programs. An incipient fertility decline could be observed in the metropolitan and more educated population sectors beginning in the early 1960s. The onset of the mortality decline in the 1930s resulted from the sustained social and economic progress made possible after the conclusion of the Mexican Revolution. Between 1930 and 1980, the adult illiteracy rate declined from 61.2% to 17%, while life expectancy increased from 33 years to 63.2 years. In Mexico as in other Latin American countries, the mortality decline, which disturbed the traditional balance between high mortality and high fertility, was the force setting off the demographic transition and the necessary precursor to fertility decline. The first of two main sections of the book focuses on examination of fertility variations in Mexico since around 1900 using cross-sectional and longitudinal methods of analysis. The second part describes the origins, history, and institutions involved in Mexico's population policies and the demographic programs and their principal results. The influence of population policies in demographic change is assessed, especially in the case of fertility changes induced by family planning programs. Both the first and second parts sought to place

  12. Semai Senoi fertility and population dynamics: Two-census method.

    Science.gov (United States)

    Fix, Alan G

    1989-01-01

    The fertility and parameters of population growth of the Semai Senoi of Malaysia are studied by using a two-census method based on nonstable population theory. Semai fertility is shown to be moderately high; female completed fertility is 7.42 children and the crude birth rate is greater than 0.050. Previous estimates of Semai mortality rates are also moderately high but are insufficient to balance birth; thus, the overall rate of growth is presently nearly 2%. Compared with an earlier description of the pre-1969 Semai population, fertility has increased markedly leading to a nearly threefold increase in the annual growth rate. Copyright © 1989 Wiley-Liss, Inc., A Wiley Company.

  13. [High-fertility groups in Colombia, 1990].

    Science.gov (United States)

    Florez, C E

    1994-09-01

    Data from the 1990 Demographic and Health Survey (DHS), the 1985 census, and PROFAMILIA and Ministry of Health service statistics were used to analyze persistence of high fertility in different subregions and socioeconomic groups of Colombia. The 1990 DHS sample design divided the country into 13 subregions, allowing greater than usual disaggregation of data. The analytic strategy had three parts: identification of regions exhibiting high fertility during 1987-90; characterization of the regions according to macro level indicators and fertility level; and analysis of the importance of the effects of the contextual and individual variables on recent fertility by means of a multilevel multivariate model. The characterization of the regions and the multivariate analysis tested the hypothesis that contextual conditions influence fertility directly and not just as instruments of the individual characteristics of local populations. Based on demographic transition theory and available information, several contextual indicators were studied: women's status, economic role of children, infant mortality, access to modern family planning methods, and urbanization. The analysis demonstrated the existence of high fertility in 3 of the 13 geographic subregions: northeast, northwest, and Tolima Grande. The characterization of the subregions indicated that those where women had lower status, and where there was less emphasis on children's school attendance, high infant mortality, low access to family planning, and low level of urbanization were not necessarily the areas with the highest total fertility rates, suggesting that a cultural effect might also be present. The northeast and northwest subregions have cultural values and family structures different from those of the rest of Colombia and similar to other Caribbean countries: prevalence of consensual unions, early marriage, and high value of children in the household. The results of the multivariate analysis also indicated the

  14. France: High and stable fertility

    Directory of Open Access Journals (Sweden)

    Clémentine Rossier

    2008-07-01

    Full Text Available The current total fertility rate in France is around 1.9 children per woman. This is a relatively high level by current European standards and makes France an outlier, despite the fact that its other demographic trends, especially conjugal behaviour, and social and economic trends are not very different from other Western European countries. France can serve as a counterfactual test case for some of the hypotheses advanced to explain the current low level of fertility in most European countries (delay in fertility, decline in marriage, increased birth control, greater economic uncertainty. France's fertility level can be partly explained by its active family policy introduced after the Second World War, and adapted in the 1980s to accommodate women's entry into the labour force. This policy is the result of a battle, fuelled by pro-natalism, between the conservative supporters of family values and the promoters of state-supported individual equality. French family policy thus encompasses a wide range of measures based on varying ideological backgrounds, and it is difficult to classify in comparison to the more precisely focused family policies of other European welfare states. The active family policy seems to have created especially positive attitudes towards two- or three child families in France.

  15. Africa: the human dimensions of high fertility.

    Science.gov (United States)

    Foly, A

    1985-09-01

    This article describes the impact of rapid population growth and high fertility on the lives of rural families in West Africa. Population pressures have exacerbated environmental problems and made daily activities such as food production, child care, and access to water and firewood more difficult. Crowded, impoverished homes lead young people to enter into early marriages and childbearing. The lack of fertility control results in premature weaning, close child spacing, and malnutrition. Population problems further contribute to economic problems and social dislocation; symptomatic of the breakdown of the family system is the rapid increase in premarital adolescent pregnancies. Growing need for firewood has led to deforestation, which in turn has resulted in soil erosion, declining soil fertility, and poor harvests. Although women in West Africa express a desire for access to the basic necessities of life (clean water, an adequate food supply, money for children's school fees), they generally fail to perceive the connection between population pressure and decreased food production, inadequate income, and physical exhaustion. Solutions to the problem of overpopulation cannot be imposed from the outside; they must be part of the framework of African women's lives and thoughts. It is necessary to pay attention to desires of these women and their thoughts about how changes can be achieved. If problems are approached from the perspective of those most affected, connections will eventually be discovered between food production, income, family planning, and family health.

  16. Gender attitudes and fertility aspirations among young men in five high fertility East African countries.

    Science.gov (United States)

    Snow, Rachel C; Winter, Rebecca A; Harlow, Siobán D

    2013-03-01

    The relationship between women's attitudes toward gender equality and their fertility aspirations has been researched extensively, but few studies have explored the same associations among men. Using recent Demographic and Health Survey data from five high fertility East African countries, we examine the association between young men's gender attitudes and their ideal family size. Whereas several DHS gender attitude responses were associated with fertility aspirations in select countries, men's greater tolerance of wife beating was consistently associated with higher fertility aspirations across all countries, independent of education, income, or religion. Our findings highlight the overlapping values of male authority within marriage and aspirations for large families among young adult males in East Africa. Total lifetime fertility in East Africa remains among the highest worldwide: thus, governments in the region seeking to reduce fertility may need to explicitly scrutinize and address the reproduction of prevailing masculine values. © 2013 The Population Council, Inc.

  17. Fertility in Populations and in Patients: Population studies on natural fertility and prediction of treatment outcome in anovulatory infertile patients

    NARCIS (Netherlands)

    M.J.C. Eijkemans (René)

    2004-01-01

    markdownabstract__Abstract__ In most western societies, reproductive behavior is nowadays controlled to a high degree: observed fertility patterns in a population -how many children do couples get and when do they get them- are the result of choices made by individuals rather than biological

  18. [Fertility pattern of contemporary peasant and population control].

    Science.gov (United States)

    Huang, Z

    1991-04-01

    The fertility decline among people in rural areas of China where 80% of the country's population reside is the key issue in the solution of population problems in China. But the current fertility in rural areas is far above the level of government population policy requirement. Field studies and newspaper reports in some rural provinces in 1989 suggested that the prevalent family pattern among farmers is 2 sons and 1 daughter. In order to have at least 1 son, some rural families would keep having children even if they have to pay fines. The fertility aspiration of rural families could be attributed to numerous factors. The Chinese culture believes in sons to carry on family lineage. Children, especially sons, are means of old age support to rural farmers. Rural children start to contribute to family income or family welfare from a young age whereas the cost of raising children is relatively low. And the flow of wealth is generally considered in favor of parents. Because level of child mortality is still high in rural areas, farmers would want to have more children to ensure that enough survive to adulthood. Contraception failure is another cause of excessive fertility. Women who become accidentally pregnant when contraceptive methods are used would find it an excuse to have the child. The implication of contraceptive failure to fertility should not be ignored. It was estimated that with 85-90% contraceptive effectiveness, a women would have 1.2-2.4 accidental pregnancies in her life time. The difference in the acceptance of the current government population policy between urban and rural areas suggests that it is important to produce political, economic, and cultural changes which subsequently induce changes in fertility. Development of an education system and introduction of means of old age support in rural areas would be the necessary steps to achieve this goal.

  19. The effect of plant population and nitrogen fertilizer on

    Directory of Open Access Journals (Sweden)

    mohamad reza asgaripor

    2009-06-01

    Full Text Available Interest has increased towards hemp (Cannabis sativa L. fibre production due to renewed demand for natural fibre in the world. A Study was conducted in 2005 at Shirvan in Northern Khorasan province, Iran, to determine the effects of three plant populations (30, 90 and 150 plant per m2 and three rates of nitrogen application (50, 150 and 250 kg N per ha on final stand, stalk height, basal stalk diameter, total stalk yield as well as fibre content from stalk and fibre yield in male and female plants. A split plot experimental with three replications was used. The result indicated that due to enhanced competition for light at higher population on density and N2 level plant mortality was higher than other treatment Morphological characteristics were highly correlated with plant sexual, plant population and nitrogen fertilizer. Highest stem, leaf and inflorescence yield were obtained at 250 plant m-2 when 150 kg N ha-1 was used. Lowest plant density did not show self-thinning but reduced above ground dry matter. Shoot dry matter increased with increasing plant density and nitrogen supply. Apparently, fibre content was greater at medium density and lowest nitrogen fertilizer, however, fibre yield was greatest at highest plant population and nitrogen fertilizer. In terms of fibre yield, approximate 31.7% of the fibre was located in the bottom parts, 22.4% in the middle and only 9.9% in the top part of the stem. The results suggest that hemp can yield large quantities of useful fibre at Shirvan when planted in proper plant densities and suitable nitrogen fertilizer.

  20. Effects of fertilizer types and varying population on the performance ...

    African Journals Online (AJOL)

    On the two-year averages,the significant percentage increases in the length of cocoyam cormel under fertilizer types were 67, 93 and 148% by inorganic, organic and inorganic + organic fertilizers, respectively. The significant percentage decreases in the length of cocoyam cormels under varying populations of 10,000, ...

  1. Wealth, fertility and adaptive behaviour in industrial populations

    Science.gov (United States)

    2016-01-01

    The lack of association between wealth and fertility in contemporary industrialized populations has often been used to question the value of an evolutionary perspective on human behaviour. Here, we first present the history of this debate, and the evolutionary explanations for why wealth and fertility (the number of children) are decoupled in modern industrial settings. We suggest that the nature of the relationship between wealth and fertility remains an open question because of the multi-faceted nature of wealth, and because existing cross-sectional studies are ambiguous with respect to how material wealth and fertility are linked. A literature review of longitudinal studies on wealth and fertility shows that the majority of these report positive effects of wealth, although levels of fertility seem to fall below those that would maximize fitness. We emphasize that reproductive decision-making reflects a complex interplay between individual and societal factors that resists simple evolutionary interpretation, and highlight the role of economic insecurity in fertility decisions. We conclude by discussing whether the wealth–fertility relationship can inform us about the adaptiveness of modern fertility behaviour, and argue against simplistic claims regarding maladaptive behaviour in humans. PMID:27022080

  2. Highly restricted fertility: very small families in the British fertility decline.

    Science.gov (United States)

    Anderson, M

    1998-07-01

    From the earliest stages of the British fertility decline, falling mean family size was accompanied by marked rises in the proportion of married women who remained childless or who bore only a single child. This paper summarises those changes, their impact on average family size, and the implications for estimates of the proportions of couples who attempted to space their children in the early years of marriage. The explanatory power of some commonly cited interpretations of the general decline in marital fertility is then considered in the context of this growth in number of families of highly restricted fertility. The paper highlights a need for more emphasis on descriptive and analytical approaches that are sensitive to distributions within populations. Also emphasized is the importance of developing interpretations that allow for the possibility that different factors may operate on different sub-sets of families at different points in time.

  3. Potential effects of incorporating fertility control into typical culling regimes in wild pig populations

    Science.gov (United States)

    Davis, Amy J.; Cunningham, Fred L.; VerCauteren, Kurt C.; Eckery, Doug C.

    2017-01-01

    Effective management of widespread invasive species such as wild pigs (Sus scrofa) is limited by resources available to devote to the effort. Better insight of the effectiveness of different management strategies on population dynamics is important for guiding decisions of resource allocation over space and time. Using a dynamic population model, we quantified effects of culling intensities and time between culling events on population dynamics of wild pigs in the USA using empirical culling patterns and data-based demographic parameters. In simulated populations closed to immigration, substantial population declines (50–100%) occurred within 4 years when 20–60% of the population was culled annually, but when immigration from surrounding areas occurred, there was a maximum of 50% reduction, even with the maximum culling intensity of 60%. Incorporating hypothetical levels of fertility control with realistic culling intensities was most effective in reducing populations when they were closed to immigration and when intrinsic population growth rate was too high (> = 1.78) to be controlled by culling alone. However, substantial benefits from fertility control used in conjunction with culling may only occur over a narrow range of net population growth rates (i.e., where net is the result of intrinsic growth rates and culling) that varies depending on intrinsic population growth rate. The management implications are that the decision to use fertility control in conjunction with culling should rely on concurrent consideration of achievable culling intensity, underlying demographic parameters, and costs of culling and fertility control. The addition of fertility control reduced abundance substantially more than culling alone, however the effects of fertility control were weaker than in populations without immigration. Because these populations were not being reduced substantially by culling alone, fertility control could be an especially helpful enhancement to culling

  4. Potential effects of incorporating fertility control into typical culling regimes in wild pig populations.

    Science.gov (United States)

    Pepin, Kim M; Davis, Amy J; Cunningham, Fred L; VerCauteren, Kurt C; Eckery, Doug C

    2017-01-01

    Effective management of widespread invasive species such as wild pigs (Sus scrofa) is limited by resources available to devote to the effort. Better insight of the effectiveness of different management strategies on population dynamics is important for guiding decisions of resource allocation over space and time. Using a dynamic population model, we quantified effects of culling intensities and time between culling events on population dynamics of wild pigs in the USA using empirical culling patterns and data-based demographic parameters. In simulated populations closed to immigration, substantial population declines (50-100%) occurred within 4 years when 20-60% of the population was culled annually, but when immigration from surrounding areas occurred, there was a maximum of 50% reduction, even with the maximum culling intensity of 60%. Incorporating hypothetical levels of fertility control with realistic culling intensities was most effective in reducing populations when they were closed to immigration and when intrinsic population growth rate was too high (> = 1.78) to be controlled by culling alone. However, substantial benefits from fertility control used in conjunction with culling may only occur over a narrow range of net population growth rates (i.e., where net is the result of intrinsic growth rates and culling) that varies depending on intrinsic population growth rate. The management implications are that the decision to use fertility control in conjunction with culling should rely on concurrent consideration of achievable culling intensity, underlying demographic parameters, and costs of culling and fertility control. The addition of fertility control reduced abundance substantially more than culling alone, however the effects of fertility control were weaker than in populations without immigration. Because these populations were not being reduced substantially by culling alone, fertility control could be an especially helpful enhancement to culling for

  5. High coffee population density to improve fertility of an oxisol Densidade populacional de cafeeiros para melhorar a fertilidade de um latossolo

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    Marcos Antonio Pavan

    1999-03-01

    Full Text Available The objective of this work was to evaluate the effect of coffee (Coffea arabica L. population densities on the chemical and microbiological properties of an Oxisol. The work was carried out on soil samples of 0-20 cm depth originated from an experimental site which had been used for coffee tree spacing studies during 15 years, in Paraná State, Brazil. Eight coffee tree populations were evaluated: 7143, 3571, 2381, 1786, 1429, 1190, 1020, and 893 trees/ha. Increasing plant population increased soil pH, exchangeable Ca, Mg, K, extractable P, organic carbon, moisture content and coffee root colonization by vesicular arbuscular mycorrhizal fungi, and decreased exchangeable Al and microbial biomass. Such results were attributed to better erosion control, improved plant residue management and nutrient cycling, and decreased leaching losses. Increasing coffee tree population per unit of area has shown to be an important reclamation recuperation strategy for improving fertility of the acid soils in Paraná, Brazil.O objetivo deste trabalho foi verificar os efeitos de diferentes densidades de população de cafeeiros (Coffea arabica L. nas propriedades químicas, físicas e microbiológicas do solo. Amostras de um Latossolo foram coletadas na profundidade 0-20 cm em um experimento de campo onde estavam sendo avaliadas diferentes populações de cafeeiros. Os tratamentos foram 7.143, 3.571, 2.381, 1.786, 1.429, 1.190, 1.020 e 893 covas/ha. Os resultados demonstraram que o aumento da população de plantas por unidade de área aumentou o pH, o Ca, o Mg e o K trocáveis, o P disponível, o carbono orgânico, o teor de umidade e a colonização radicular por micorrizas, e diminuiu o Al trocável e a biomassa microbiana. Foram considerados como causas da melhoria da fertilidade do solo, sob cafeeiros adensados, o adequado controle da erosão, o correto manejo dos resíduos vegetais e a baixa lixiviação dos íons. O manejo da população de cafeeiros pode

  6. The Missing Children: Mortality and Fertility in a Southeast Asian Refugee Population.

    Science.gov (United States)

    Gordon, Linda W.

    1989-01-01

    Presents the age-sex structures of refugee populations arriving in the United States from Cambodia, Laos, and Vietnam from 1975 through 1986. Differences in the composition of these young populations reflect varying flight and resettlement experiences and changing factors influencing migration. High fertility rates predict a generation of rapid…

  7. Wealth, fertility and adaptive behaviour in industrial populations

    NARCIS (Netherlands)

    Stulp, Gert; Barrett, Louise

    2016-01-01

    The lack of association between wealth and fertility in contemporary industrialized populations has often been used to question the value of an evolutionary perspective on human behaviour. Here, we first present the history of this debate, and the evolutionary explanations for why wealth and

  8. Forecasting births in post-transition population: stochastic renewal with serially correlated fertility.

    Science.gov (United States)

    Lee, R D

    1974-09-01

    Time series analysis of fertility can improve demographic forecasts. The optimal forecast and its variance for births to an age-structured population subject to serially correlated random fertility are developed. The general case in which the fertility process had arbitrary autoregressive structure is dealt with and then the 4 special cases of white noise, 1st-order autoregressive, 2nd-order autoregressive, and random walk are considered. Consequently, it is determined that the predictions and their variances are highly sensitive to the autoregressive structure of fertility and, therefore, if stochastic models are to be used for prediction, they must emphasize this aspect of the problem. Preliminary empirical efforts to model the time series of U.S. fertility from 1917 to 1972 proved unsuccessful, but it is obvious that at least a 2nd-order autoregressive scheme is require d. The analysis proveded should be helpful in: 1) any application of the procedures requires a successful parameterization of the fertility process; 2) fertility variations could be decomposed into the effects of nuptiality and marital fertility and then births and marriages could be jointly predicted; and 3) the simplifying approximations should be dropped and each age-specific rate could be analyzed and predicted.

  9. A New Proposal for Measuring Marital Fertility in Historical Populations

    Directory of Open Access Journals (Sweden)

    Sánchez-Barricarte, Jesús J.

    2001-01-01

    Full Text Available EnglishIn this paper, a critical analysis is made of some of the indices used innumerous historical studies on the decline of fertility. More concretely, it is demonstrated how theTotal Marital Fertility Rate (TMFR and the Ig and I'g indices of marital fertility designed by Coale(1986 not only are not good indicators of a population's level of marital fertility, but also in somecases (for example, when there is an important delay in female mean age at marriage can even indicatean increase in marital fertility when in reality it is decreasing. Likewise, a new index for measuringmarital fertility (known as the Navarre Index is presented which takes into account women's averageage at marriage as well as their mortality rate during their reproductive period.FrenchDans cet article, une analyse critique est faite sur quelques-uns des indicesutilisés dans de nombreuses études historiques concernant la diminution de lafécondité. Plus concrètement, il est démostré comment le Taux de FéconditéMaritale Totale et les indices Ig et I’g de fécondité maritale désignés par Coale(1986 non seulement ne sont pas de bons indicateurs d’un niveau de féconditémaritale de population, mais, dans certains cas (par example, quand il y a unretard important dans l’âge moyen de mariage des femmes, ils peuvent mêmeindiquer une augmentation de la fécondité maritale lorsqu’en réalité il s’agitd’une diminution. Un nouvel indice pour mesurer la fécondité maritale (connucomme l’Indice de Navarre est aussi présenté, qui prend en considération l’âgemoyen de mariage pour les femmes, et, en même temps, leur taux de mortalitépendant leur période reproductive.

  10. Association of general population suicide rates with fertility rates: a test of fertility as a measure of social integration.

    Science.gov (United States)

    Bhandarkar, Ritesh; Shah, Ajit

    2008-12-01

    A negative correlation between societal suicide rates and social integration has been reported using data within individual countries; however, this has rarely been examined cross-nationally. The relation of general population suicide rates with fertility rates across 75 countries was examined for data from the World Health Organization and the United Nations. Social integration has been defined as the extent to which members of society are bound together in social relationships, and higher fertility rates, reflecting greater vigour and unity of the family, serve as a proxy measure of social integration. Multiple regression analysis indicated that general population suicide rates in males and females were independently correlated with fertility rates. The relation of general population suicide rates with fertility rates was also curvilinear (U-shaped curve). Explanation of the observed curvilinear relationship requires further study.

  11. Are blastocyst aneuploidy rates different between fertile and infertile populations?

    Science.gov (United States)

    Kort, Jonathan D; McCoy, Rajiv C; Demko, Zach; Lathi, Ruth B

    2017-10-23

    This study aimed to determine if patients with infertility or recurrent pregnancy loss have higher rates of embryo aneuploidy than fertile controls. This was a retrospective review of all pre-implantation genetic screening (PGS) cases processed by a single reference lab prior to March 2014 after a blastocyst biopsy. Cases were excluded if no indication for PGS was designated or patients were translocation carriers. The fertile control group consisted of patients undergoing IVF with PGS for sex selection only. The comparison cohorts included those with recurrent pregnancy loss, male factor infertility, unexplained infertility, prior failed IVF, or previous aneuploid conceptions. A quasi-binomial regression model was used to assess the relationship between the dependent variable, aneuploidy rate and the independent variables, maternal age and reason for PGS. A quasi-Poisson regression model was used to evaluate the relationship between similar independent variables and the number of blastocyst biopsies per case. The initial study population consisted of 3378 IVF-PGS cycles and 18,387 analyzed trophectoderm samples. Controlling for maternal age, we observed an increased rate of aneuploidy among patients with recurrent pregnancy loss (OR 1.330, p  0.05). The increase in aneuploidy in patients with RPL and prior IVF failure was driven by both an increase in meiotic (OR 1.488 and 1.508, p < 0.05) and mitotic errors (1.269 and 1.393, p < 0.05) relative to fertile controls, while patients with prior aneuploid pregnancies had only an increased risk of meiotic error aneuploidies (OR 1.650, p < 0.05). Patients with recurrent pregnancy loss, previous IVF failures, and prior aneuploid pregnancies have a significantly higher, age-independent, aneuploidy rate compared to patients without infertility.

  12. 76 FR 75869 - Proposed Information Collection; Comment Request; Current Population Survey (CPS) Fertility...

    Science.gov (United States)

    2011-12-05

    ... Census Bureau Proposed Information Collection; Comment Request; Current Population Survey (CPS) Fertility... Fertility Supplement to be conducted in conjunction with the June 2012 CPS. The Census Bureau sponsors the... 1971. This year, the 2012 Fertility Supplement will include revised questions on marital status and...

  13. Bringing population education closer to effecting fertility behaviour.

    Science.gov (United States)

    1991-01-01

    When population education programs are linked to community outreach efforts, there may be a direct and immediate impact of fertility. Examples are given of 2 such programs in India and china. In India, state and nongovernmental resources support Maharashtra's 34 women's Development Camps (WDC) for women of childbearing age, which propose to affect fertility behavior and improve quality of life. 9 of these WDCs were set up in densely populated and low income areas, i.e., in Bombay, Pune, and Nashik. The remaining 25 were in rural areas. The 1035 women who participated tend to reflect the conditions of work overload and nutritional deprivation with few rights of decision making. Population education was tailored to the most immediate needs of participants. The aim was to develop awareness and understanding of population as it is related to socioeconomic development, family health, family and community living, and civic responsibilities which benefit the individual, family, community, and society. Critical thinking skills were developed, as well as the awareness of primary health care for women, children, and the family. This involved information on maternal and child care, personal and social hygiene, and the importance of women's education and literacy. Women's rights were discussed in terms of laws for women, consumers' protection act, inheritance rights, irrational beliefs and superstitions, and the injustices of castes and society. Training was given in handicraft making, other employment schemes, energy saving devices such as solar cookers and hand water pumps, sanitation, as well as savings opportunities. Personality development through the use of yoga, and warnings about alcohol, smoking, and drug taking were encouraged. Innovative methods were used to maintain involvement. In China, 34 Peasant Secondary Vocational Schools in Hunan province (1000 teachers and cadres and 25,000 students) provided courses in reproductive responsibility. Specific school results

  14. A New Proposal for Measuring Marital Fertility in Historical Populations

    Directory of Open Access Journals (Sweden)

    Jesús J. Sánchez-Barricarte

    2001-12-01

    Full Text Available In this paper, a critical analysis is made of some of the indices used in numerous historical studies on the decline of fertility. More concretely, it is demonstrated how the Total Marital Fertility Rate (TMFR and the Ig and I’g indices of marital fertility designed by Coale (1986 not only are not good indicators of a population’s level of marital fertility, but also in some cases (for example, when there is an important delay in female mean age at marriage can even indicate an increase in marital fertility when in reality it is decreasing. Likewise, a new index for measuring marital fertility (known as the Navarre Index is presented which takes into account women’s average age at marriage as well as their mortality rate during their reproductive period.

  15. The long-term effect of the timing of fertility decline on population size

    NARCIS (Netherlands)

    O'Neill, BC; Scherbov, S; Lutz, W

    1999-01-01

    Existing long-range population projections imply that the timing of the fertility transition has a relatively unimportant effect on long-term population size when compared with the impact of the level at which fertility is assumed eventually to stabilize. However, this note shows that the effect of

  16. Mares prefer the voices of highly fertile stallions.

    Science.gov (United States)

    Lemasson, Alban; Remeuf, Kévin; Trabalon, Marie; Cuir, Frédérique; Hausberger, Martine

    2015-01-01

    We investigated the possibility that stallion whinnies, known to encode caller size, also encoded information about caller arousal and fertility, and the reactions of mares in relation to type of voice. Voice acoustic features are correlated with arousal and reproduction success, the lower-pitched the stallion's voice, the slower his heart beat and the higher his fertility. Females from three study groups preferred playbacks of low-pitched voices. Hence, females are attracted by frequencies encoding for large male size, calmness and high fertility. More work is needed to explore the relative importance of morpho-physiological features. Assortative mating may be involved as large females preferred voices of larger stallions. Our study contributes to basic and applied ongoing research on mammal reproduction, and questions the mechanisms used by females to detect males' fertility.

  17. Mares prefer the voices of highly fertile stallions.

    Directory of Open Access Journals (Sweden)

    Alban Lemasson

    Full Text Available We investigated the possibility that stallion whinnies, known to encode caller size, also encoded information about caller arousal and fertility, and the reactions of mares in relation to type of voice. Voice acoustic features are correlated with arousal and reproduction success, the lower-pitched the stallion's voice, the slower his heart beat and the higher his fertility. Females from three study groups preferred playbacks of low-pitched voices. Hence, females are attracted by frequencies encoding for large male size, calmness and high fertility. More work is needed to explore the relative importance of morpho-physiological features. Assortative mating may be involved as large females preferred voices of larger stallions. Our study contributes to basic and applied ongoing research on mammal reproduction, and questions the mechanisms used by females to detect males' fertility.

  18. Ecological feedbacks can reduce population-level efficacy of wildlife fertility control

    Science.gov (United States)

    Ransom, Jason I.; Powers, Jenny G.; Hobbs, N. Thompson; Baker, Dan L.

    2014-01-01

    1. Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. 2. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. 3. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. 4. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. 5. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife

  19. How high is Hispanic/Mexican fertility in the united states? Immigration and tempo considerations.

    Science.gov (United States)

    Parrado, Emilio A

    2011-08-01

    In this article, I demonstrate that the apparently much higher fertility of Hispanic/Mexican women in the United States is almost exclusively the product of period estimates obtained for immigrant women and that period measures of immigrant fertility suffer from three serious sources of bias that together significantly overstate fertility levels: difficulties in estimating the size of immigrant groups; the tendency for migration to occur at a particular stage in life; and, most importantly, the tendency for women to have a birth soon after migration. When these sources of bias are taken into consideration, the fertility of native Hispanic/Mexican women is very close to replacement level. In addition, the completed fertility of immigrant women in the United States is dramatically lower than the level obtained from period calculations. Findings are consistent with classical theories of immigrant assimilation but are a striking departure from the patterns found in previous studies and published statistics. The main implication is that without a significant change in immigration levels, current projections based on the premise of high Hispanic fertility are likely to considerably exaggerate Hispanic population growth, its impact on the ethno-racial profile of the country, and its potential to counteract population aging.

  20. High fertility and development in Cameroon | Nana-Fabu | Journal of ...

    African Journals Online (AJOL)

    High fertility and development in Cameroon. ... Journal of Social Development in Africa ... Many scholars of development, in sub Saharan Africa especially, have come to perceive increases in the African population as a threat to what is an already precarious balance between people and scarce natural resources, as well as ...

  1. A Biosocial View of Population: Fertility Behavior in Animal Groups and Early Human Societies. A Review.

    Science.gov (United States)

    Murphy, Elaine M.

    The paper discusses the relationship between social structure and fertility behavior in man. Focusing upon human fertility within the context of varying social groups, the document reviews recent interdisciplinary population studies. Information and interpretations from biology, ethnology, anthropology, history, and sociology are presented in four…

  2. Denitrification of fertilizer wastewater at high chloride concentration

    DEFF Research Database (Denmark)

    Ucisik, Ahmed Süheyl; Henze, Mogens

    Wastewater from fertilizer industry is characterized by high contents of chloride concentration, which normally vary between 60 and 76 g/l. Experiments with bilogical denitrification were performed in lab-scale "fill and draw" reactors with synthetic wastewater with chloride concentrations up to 77.......4 g/l. The results of the experiments showed that biological denitrification was feasible at the extreme environmental conditions prevailing in fertilizer wastewater. Stable continuous biological denitrfication of the synthetic high chloride wastewater was performed up to 77.4 g Cl/l at 37 degree C...

  3. Biotransformation of Organic Waste into High Quality Fertilizer

    DEFF Research Database (Denmark)

    Bryndum, Sofie

    Agriculture faces several challenges of future provision of nutrients such as limited P reserves and increasing prices of synthetic fertilizers and recycling of nutrients from organic waste can be an important strategy for the long-term sustainability of the agricultural systems. Organically...... and S, is often low; and (3) the unbalanced composition of nutrients rarely matches crop demands. Therefore the objective of this project was to investigate the potential for (1) recycling nutrients from agro-industrial wastes and (2) compost biotransformation into high-quality organic fertilizers......, including three succeeding compost experiments, conducted in Denmark (Paper II). The composting studies investigated three management interventions to enhance the compost fertilizer quality and accelerate compost turnover: (1) the addition of nutrient rich material, (2) the compost turning frequency and (3...

  4. High ratings of satisfaction with fertility treatment are common

    DEFF Research Database (Denmark)

    Schmidt, L; Holstein, B E; Boivin, J

    2003-01-01

    /delivery and the report of marital benefits resulting from the infertility experience. Lower social class was a significant predictor for satisfaction. CONCLUSIONS: Both men and women in fertility treatment had high ratings on medical and patient-centred care. It seemed that satisfaction with the psychosocial services...

  5. Use of fertility drugs and risk of ovarian cancer: Danish Population Based Cohort Study

    DEFF Research Database (Denmark)

    Jensen, Allan; Sharif, Heidi; Frederiksen, Kirsten

    2009-01-01

    OBJECTIVE: To examine the effects of fertility drugs on overall risk of ovarian cancer using data from a large cohort of infertile women. DESIGN: Population based cohort study. SETTING: Danish hospitals and private fertility clinics. PARTICIPANTS: 54,362 women with infertility problems referred...... subcohort members identified in the cohort during follow-up in 2006. MAIN OUTCOME MEASURE: Effect of four groups of fertility drugs (gonadotrophins, clomifene citrate, human chorionic gonadotrophin, and gonadotrophin releasing hormone) on overall risk of ovarian cancer after adjustment for potential...... hormone (0.80, 0.42 to 1.51). Furthermore, no associations were found between all four groups of fertility drugs and number of cycles of use, length of follow-up, or parity. CONCLUSION: No convincing association was found between use of fertility drugs and risk of ovarian cancer....

  6. Nigeria's Population Policy and Future Fertility Decline | Mba ...

    African Journals Online (AJOL)

    The government of the Federal Republic of Nigeria, Africa's most populous country, promulgated its first explicit population policy in 1988, in response to the soaring population growth rate that impedes developmental efforts. The policy document has stipulated a number of quantitative demographic targets. Paramount ...

  7. The effects of mortality on fertility: population dynamics after a natural disaster.

    Science.gov (United States)

    Nobles, Jenna; Frankenberg, Elizabeth; Thomas, Duncan

    2015-02-01

    Understanding how mortality and fertility are linked is essential to the study of population dynamics. We investigate the fertility response to an unanticipated mortality shock that resulted from the 2004 Indian Ocean tsunami, which killed large shares of the residents of some Indonesian communities but caused no deaths in neighboring communities. Using population-representative multilevel longitudinal data, we identify a behavioral fertility response to mortality exposure, both at the level of a couple and in the broader community. We observe a sustained fertility increase at the aggregate level following the tsunami, which was driven by two behavioral responses to mortality exposure. First, mothers who lost one or more children in the disaster were significantly more likely to bear additional children after the tsunami. This response explains about 13 % of the aggregate increase in fertility. Second, women without children before the tsunami initiated family-building earlier in communities where tsunami-related mortality rates were higher, indicating that the fertility of these women is an important route to rebuilding the population in the aftermath of a mortality shock. Such community-level effects have received little attention in demographic scholarship.

  8. Functional incompatibility between the fertilization systems of two allopatric populations of Callosobruchus maculatus (Coleoptera: Bruchidae).

    Science.gov (United States)

    Brown, D V; Eady, P E

    2001-11-11

    Recent studies indicate that postcopulatory sexual selection may represent an important component of the speciation process by initiating reproductive isolation via the evolutionary divergence of fertilization systems. Using two geographically isolated populations of the polyandrous beetle Callosobruchus maculatus, we investigated divergence in fertilization systems by determining the extent of postcopulatory functional incompatibility. Through reciprocal, cross-population matings we were able to separately estimate the effects of male and female population origin and their interaction on the extent of last-male sperm precedence, female receptivity to further copulation and female oviposition. Our results indicate partial incompatibility between the fertilization systems of the two populations at all three functional levels. Males derived from the same population as females outcompete rival, allopatric males with respect to sperm preemption, sperm protection, and ability to stimulate female oviposition. This pattern is reciprocated in both populations indicating that postcopulatory, prezygotic events represent important mechanisms by which between-population gene flow is reduced. We suggest the partial gametic isolation observed is a by-product of the coevolution of male and female fertilization systems by a process of cryptic female choice. Our results are consistent with a mechanism akin to conventional mate choice models although they do not allow us to reject antagonistic sexual coevolution as the mechanism of cryptic female choice.

  9. Fertility change in the American Indian and Alaska Native population, 1980-2010

    Directory of Open Access Journals (Sweden)

    Sarah Cannon

    2017-07-01

    Full Text Available Background: Since 1990, Vital Statistics reports show a dramatic decline in the total fertility rates (TFRs of American Indian and Alaska Native (AI/AN women in the United States. Objective: We study whether the decrease in TFRs is due to a real change in fertility for a stable population; a compositional change in who identifies as AI/AN; or a methodological issue stemming from differences in identifying race across the data systems used to calculate fertility rates. Methods: We use data from the decennial US Census to study change in AI/AN fertility from 1980-2010. Results: We find declining TFRs when fertility is calculated within a single data system. Additionally, although TFRs are relatively stable within the subgroups of married and unmarried AI/AN women, the proportion of AI/AN women who are married has declined across birth cohorts. Conclusions: The decrease in TFRs for AI/AN women is a real change in fertility patterns and is not due to differences in racial identification across data systems. Contribution: We update knowledge of AI/AN fertility to include the decline in TFRs between 1980 and 2010.

  10. Minimizing the dependency ratio in a population with below-replacement fertility through immigration

    Science.gov (United States)

    Simon, C.; Belyakov, A.O.; Feichtinger, G.

    2012-01-01

    Many industrialized countries face fertility rates below replacement level, combined with declining mortality especially in older ages. Consequently, the populations of these countries have started to age. One important indicator of age structures is the dependency ratio which is the ratio of the nonworking age population to the working age population. In this work we find the age-specific immigration profile that minimizes the dependency ratio in a stationary population with below-replacement fertility. It is assumed that the number of immigrants per age is limited. We consider two alternative policies. In the first one, we fix the total number of people who annually immigrate to a country. In the second one, we prescribe the size of the receiving country’s population. For both cases we provide numerical results for the optimal immigration profile, for the resulting age structure of the population, as well as for the dependency ratio. PMID:22781918

  11. Fertility/longevity trade offs under limiting-male conditions in mating populations of Caenorhabditis elegans

    OpenAIRE

    Wu, Deqing; Tedesco, Patricia M.; Phillips, Patrick C.; Johnson, Thomas E.

    2012-01-01

    Evolutionary theories of aging suggest that trade-offs between longevity and fitness should be found under certain conditions. In C. elegans, there is little evidence for the existence of such tradeoffs. We asked if fertility/longevity trade-offs exist in populations of randomly mating males and hermaphrodites. We set up a large population of young males and 5-day-old hermaphrodites that were no longer self-fertile. We then allowed them to mate for one day with an equal number young males and...

  12. Regional variation in fertility, mortality and population growth in Ethiopia, 1970-1981.

    Science.gov (United States)

    Kidane, A

    1990-01-01

    Statisticians cleaned and adjusted data from the 1970 and 1981 demographic surveys conducted by the Central Statistics Office of Ethiopia to do this demographic analysis. The mean age at marriage increased from 1970-1981 in all administrative regions of Ethiopia (data did not include Eritrea and Tigrai) with the most change occurring in the southern regions (20.5% vs. 5%). Even though the biggest increases occurred in the female population, the mean age at marriage remained low hence having little impact on fertility. Indeed total fertility grew in all administrative regions with the greatest increase in the southern regions (26% vs. 19%). This change could be attributable to the increased disposable income in the southern regions bringing about better nutrition and better health facilities. Since the population of 2 regions in the south consisted of nomads who normally maintain low fertility levels, the total fertility did not change. In the northern regions, the population of 2 regions experienced no change in total fertility because of the continuing drought and famine. Despite widespread underreporting, researchers estimated at 26% and 27% of the population in the northern and southern regions respectively died before age 5 in 1970. There was little reduction in mortality in 1981 (22% and 26% respectively). The population grew between 1970-1981 in both regions. In the northern region, the growth rate increased from 2.44- 2.76 (13% change) while in the southern region, it increased from 2.36- 2.69 (14% change). Little voluntary control of fertility occurred in this time span. Clearly the government must pass legislation to raise the age at marriage and implement a comprehensive family planning program countrywide.

  13. Computer-assisted semen analysis parameters as predictors for fertility of men from the general population

    DEFF Research Database (Denmark)

    Larsen, L; Scheike, Thomas Harder; Jensen, Tina Kold

    2000-01-01

    The predictive value of sperm motility parameters obtained by computer-assisted semen analysis (CASA) was evaluated for the fertility of men from general population. In a prospective study with couples stopping use of contraception in order to try to conceive, CASA was performed on semen samples...

  14. Effect of plant population and N fertilizer on the growth and yield of ...

    African Journals Online (AJOL)

    Responses of bambara groundnut (Vigna subterranea (L.) Verdc) to 3 levels of fertilizer N (0, 50, and 100 kg N/ha) and seven plant populations (55555, 63492, 74074, 88888, 111111, 148148 and 222222 plants/ha) were studied under field conditions in Nsukka, Nigeria. The experimental design was a randomized ...

  15. Reproduction in high altitude Aymara: physiological stress and fertility planning?

    Science.gov (United States)

    Crognier, E; Villena, M; Vargas, E

    2002-10-01

    Reproductive characteristics at high altitude are described based on the reproductive histories of 720 Aymara women, collected in 1998 and 1999 in a group of twelve peasant communities at a mean altitude of 4000 m in the Bolivian Altiplano. The reproductive pattern is shaped by a late onset of childbearing, associated with a rather short reproductive span and large birth intervals. Environmental conditions could explain the particularly late age at menarche of rural girls compared with their urban counterparts, whereas the age at first birth is likely to be under cultural control. The short reproductive span appears to result from a large mean interval between last birth and menopause, which is essentially determined by cultural decisions. The birth intervals, which are longer than in many traditional societies, could be the result of a slower restoration of postpartum fecundability induced by the hard way of life inherent in the Altiplano (including poor sanitary and nutritional conditions and high workload), perhaps aggravated by hypoxia. However, a secular trend in fertility is perceptible, towards earlier menarche, earlier age at first birth, increasing reproductive span and a slight increase in live births and surviving offspring, which is probably the result of a slow improvement in living conditions. The existence of birth control on the one hand, and a total fertility rate averaging six live births among the couples who do not practise contraception on the other, are other arguments against the hypothesis of a low natural fecundity in these Aymara groups.

  16. Overlapping chromosomal regions for fertility traits and production traits in the Danish Holstein population

    DEFF Research Database (Denmark)

    Höglund, Johanna Karolina; Buitenhuis, A J; Guldbrandtsen, B

    2009-01-01

    production traits conditional on the QTL regions for the subtraits and retained placenta was conducted. Second, we selected 24 genomic regions harboring QTL for fertility traits from a previous study. A QTL scan for milk production traits conditional on the selected regions was conducted. We found that 16......, it is of interest to validate which of the subtraits are affected by the QTL. Phenotypic and marker data were collected from 34 grandsire families from the Danish Holstein population. First, the trait data for "fertility treatments" were separated into their underlying subtraits: uterine infections, antibiotics...... placed in the placenta, and abortions. In addition, retained placenta was selected for analysis because it is related to uterine infections. A genome scan was performed using 416 microsatellite markers for the fertility treatment subtraits and retained placenta, and an additional genome scan for milk...

  17. Population ecology of feral horses in an era of fertility control management

    Science.gov (United States)

    Ransom, J.I.

    2012-01-01

    Management of wildlife often requires intervention to regulate growth of populations that would otherwise become overabundant. Controlling fecundity using contraceptives has become an increasingly popular tool for attempting to manage locally overabundant wildlife species, but the population-level effects of such applications are largely unknown. Contraceptive treatments can produce unexpected feedbacks that act on births, survival, immigration, and emigration. Such feedbacks may considerably influence our ability to regulate populations using fertility control. I followed feral horses (Equus caballus) in three intensively managed populations to assess longitudinal treatment effects on demography. The transient contraceptive porcine zona pellucida (PZP) produced longer duration of infertility than intended. Repeated PZP vaccinations of females extended the duration of infertility far beyond the targeted management period, with time to first post-treatment parturition increasing 411days for every annual inoculation received. When these animals did conceive and give birth, parturition was later in the year and temporally asynchronous with forage abundance. An average of 30% (range=11–77%) of females were contracepted annually during the treatment period in all three populations and apparent annual population growth rate was 4–9% lower in the post-treatment years as compared to pretreatment years. Population growth was positive, however, and increased steadily every year that a management removal did not occur. The observed number of births was 33% fewer than the expected number of births, based on number of treated females, individual efficacy of treatment, and number of untreated females and their age-specific fecundity rates. Only half of this difference was explained by the apparent residual effect of treatment. Birth rate in the youngest untreated females (age 2–5 years old) was reduced in years when their conspecifics were treated, enhancing the effects of

  18. On low fertility from the aspect of the economic activity of female population: Possibilities and restrictions in encouragement of childbearing

    Directory of Open Access Journals (Sweden)

    Šobot Ankica

    2014-01-01

    (Ignjatović, et al., 2011. The gender inequality on the micro level represents an unfavorable social framework for making childbearing decisions due to relatively high economic activity of women. Apart from that, high unemployment of both female and male population in Serbia is yet another adverse circumstance for forming a family and making decisions on births. Also, a challenge in reversal of low birth rates are regional differences of socio-economic characteristics of the female population. In that sense, the share of economically inactive among women of reproductive age in Vojvodina and two regions in Central Serbia area (excluding the region of Belgrade, as well as lower fertility of employed and unemployed women in the Belgrade region, are imposed. Economic activity and employment of female population form a positive framework in reproductive behavior, if the conditions regarding the characteristics of gender regime are fulfilled. In such circumstances fertility is around the replacement rate, which represents the highest birth rate values in European welfare states. Having in mind high valuation of family and parenthood on one hand, and economic characteristics of the female population in Serbia on the other, the question is whether the economic activity of women is the area where encouragement of childbearing to more than two children could be influenced. The reply requires more in-depth analysis of relevant data, as well as more concrete empirical and better quality research.

  19. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    Science.gov (United States)

    Lawrence, Dan; Philip, Graham; Hunt, Hannah; Snape-Kennedy, Lisa; Wilkinson, T J

    2016-01-01

    Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

  20. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    Directory of Open Access Journals (Sweden)

    Dan Lawrence

    Full Text Available Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

  1. Fertility rates and perinatal outcomes of adolescent pregnancies: a retrospective population-based study

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    Maria de Lourdes de Souza

    Full Text Available ABSTRACT Objective: analyze trends in fertility rates and associations with perinatal outcomes for adolescents in Santa Catarina, Brazil. Methods: a population-based study covering 2006 to 2013 was carried out to evaluate associations between perinatal outcomes and age groups, using odds ratios, and Chi-squared tests. Results: differences in the fertility rate among female adolescents across regions and time period were observed, ranging from 40.9 to 72.0 per 1,000 in mothers aged 15-19 years. Adolescents had fewer prenatal care appointments than mothers ≥20 years, and a higher proportion had no partner. Mothers aged 15-19 years were more likely to experience preterm birth (OR:1.1; CI:1.08-1.13; p<0.001, have an infant with low birthweight (OR:1.1; CI:1.10-1.15; p<0.001 and low Apgar score at 5 minutes (OR:1.4; CI:1.34-1.45; p<0.001 than mothers ≥20 years, with the odds for adverse outcomes greater for those aged 10-14 years. Conclusion: this study provides evidence of fertility rates among adolescents remaining higher in regions of social and economic deprivation. Adolescent mothers and their infants more likely to experience adverse perinatal outcomes. Nurses, public health practitioners, health and social care professionals and educators need to work collaboratively to better target strategies for adolescents at greater risk; to help reduce fertility rates and improve outcomes.

  2. The decrease in the population of Gluconacetobacter diazotrophicus in sugarcane after nitrogen fertilization is related to plant physiology in split root experiments.

    Science.gov (United States)

    Rodríguez-Andrade, Osvaldo; Fuentes-Ramírez, Luis E; Morales-García, Yolanda E; Molina-Romero, Dalia; Bustillos-Cristales, María R; Martínez-Contreras, Rebeca D; Muñoz-Rojas, Jesús

    2015-01-01

    It has been established that a decrease in the population of Gluconacetobacter diazotrophicus associated with sugarcane occurs after nitrogen fertilization. This fact could be due to a direct influence of NH(4)NO(3) on bacterial cells or to changes in plant physiology after fertilizer addition, affecting bacterial establishment. In this work, we observed that survival of G. diazotrophicus was directly influenced when 44.8mM of NH(4)NO(3) (640mgN/plant) was used for in vitro experiments. Furthermore, micropropagated sugarcane plantlets were inoculated with G. diazotrophicus and used for split root experiments, in which both ends of the system were fertilized with a basal level of NH(4)NO(3) (0.35mM; 10mgN/plant). Twenty days post inoculation (dpi) one half of the plants were fertilized with a high dose of NH(4)NO(3) (6.3mM; 180 mgN/plant) on one end of the system. This nitrogen level was lower than that directly affecting G. diazotrophicus cells; however, it caused a decrease in the bacterial population in comparison with control plants fertilized with basal nitrogen levels. The decrease in the population of G. diazotrophicus was higher in pots fertilized with a basal nitrogen level when compared with the corresponding end supplied with high levels of NH4NO3 (100dpi; 80 days post fertilization) of the same plant system. These observations suggest that the high nitrogen level added to the plants induce systemic physiological changes that affect the establishment of G. diazotrophicus. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Fertility tables of two populations of the parthenogenetic species Poratia salvator (Diplopoda, Polydesmida, Pyrgodesmidae

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    TG Pinheiro

    Full Text Available Diplopods are very susceptible to various degrees of environmental disturbance, particularly climate, altitude and diet. In order to increase our understanding of millipede ecological plasticity, we used fertility tables to access and to compare the fertility and survival of two populations of the parthenogenetic species Poratia salvator from two areas with distinct characteristics. Collecting was conducted in two localities within the state of Mato Grosso, in the Pantanal of Mato Grosso, municipality of Nossa Senhora do Livramento, and in the municipality of Várzea Grande. The specimens were maintained at room temperature. In the first generation, individuals from the Pantanal of Mato Grosso population reproduced early and also died earlier when compared with individuals from the Várzea Grande population. Furthermore, the population from the Pantanal had a lower net reproduction rate and a higher intrinsic growth rate than the population from the Várzea Grande. The generation time was lower for the Pantanal population than for the Várzea Grande population. In the second generation, the net reproduction rate observed for both populations was higher than that observed in the first generation, suggesting an increase in the reproductive potential of the females throughout their lives. The intrinsic growth rate of both populations decreased as a function of an increase in generation time observed in the second generation. As a result, the population growth rate in the second generation was slower when compared with the first generation, probably a result of the longer life expectancy of the second generation, which may have become adapted to the artificial conditions of the experiment.

  4. GEOSPATIAL ASSESSMENT BASED ON FERTILITY AND MORTALITY DIFFERENTIAL INDICES OF NATURAL SELECTION IN NORTH-WEST AND EASTERN HIMALAYAN POPULATIONS.

    Science.gov (United States)

    Sharma, Krishan

    2017-11-01

    There is contradictory evidence of having fewer live births and higher embryonic mortality among high-altitude populations than their counterparts at lower altitude. This study explores the geospatial differences in selection intensities among human populations living in different ecological settings. Reproductive data from post-menopausal women were collected from 75 women from near Shimla, Himachal Pradesh, at an altitude of 2150 m above sea level and 100 women from Jind, Haryana, at an altitude of 227 m. Secondary data were taken from 85 women from the Kinnaur district of Himachal Pradesh at an average altitude of 3420 m. A comparison of the study data was made with similar data from different populations living in the western and eastern Himalayas. The total selection intensity index based on Johnston and Kensinger's index was highest in Shimla and lowest in Kinnaur. The fertility selection component was highest in Shimla and lowest in Kinnaur. The prenatal mortality contribution to the total selection was highest in Shimla (30.76%) and lowest in Kinnaur (2.14%), while the contributions of normalized postnatal mortality were 16.39% and 57.80% in Shimla and Kinnaur, respectively. The fertility component of selection was higher than the mortality component in Shimla, while in the other two places the reverse was observed. Hypoxic conditions at high altitude seem to have little effect on the fertility and embryonic mortality rates of indigenous people. The geospatial differences in the selection intensities may be due to differences in ethnic, behavioural ecology, environmental, cultural and socioeconomic factors.

  5. Very long range global population scenarios to 2300 and the implications of sustained low fertility

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    Stuart Basten

    2013-05-01

    Full Text Available BACKGROUND Depending on whether the global level of fertility is assumed to converge to the current European TFR (~1.5 or that of Southeast Asia or Central America (~2.5, global population will either decline to 2.3-2.9 billion by 2200 or increase to 33-37 billion, if mortality continues to decline. Furthermore, sizeable human populations exist where the voluntarily chosen ideal family size is heavily concentrated around one child per woman with TFRs as low as 0.6-0.8. However, the UN population projections to 2300 use a much narrower band of possible future TFRs. OBJECTIVE If the two-child norm is not necessarily the end-point of transition, what would be the consequences of the currently reported low fertility rates being sustained and becoming widespread? METHODS We present new projections for 13 IPCC world regions with scenarios calculated on the basis of regular cohort-component projections by age and sex in single-year time steps up to 2300, each based upon a much broader set of fertility assumptions than currently employed. We create three mortality scenarios based upon maximum life expectancies of 90, 100, and 110, as well as a series of 'special' scenarios. RESULTS Even under conditions of further substantial increases in life expectancy, world population size would decline significantly if the world in the longer run followed the current examples of Europe and East Asia. CONCLUSIONS In contrast to Malthusian disaster scenarios, our exercise illustrates the distinct possibility of significant population shrinking associated with increasing life expectancy and human well-being.

  6. Fertility rates and perinatal outcomes of adolescent pregnancies: a retrospective population-based study.

    Science.gov (United States)

    Souza, Maria de Lourdes de; Lynn, Fiona Ann; Johnston, Linda; Tavares, Eduardo Cardoso Teixeira; Brüggemann, Odaléa Maria; Botelho, Lúcio José

    2017-04-06

    analyze trends in fertility rates and associations with perinatal outcomes for adolescents in Santa Catarina, Brazil. a population-based study covering 2006 to 2013 was carried out to evaluate associations between perinatal outcomes and age groups, using odds ratios, and Chi-squared tests. differences in the fertility rate among female adolescents across regions and time period were observed, ranging from 40.9 to 72.0 per 1,000 in mothers aged 15-19 years. Adolescents had fewer prenatal care appointments than mothers ≥20 years, and a higher proportion had no partner. Mothers aged 15-19 years were more likely to experience preterm birth (OR:1.1; CI:1.08-1.13; ppobreza social y económica. Madres adolesce

  7. Fertility, knowledge, attitude and practice (KAP) study in relation to family planning in a selected population of the Armed Forces.

    Science.gov (United States)

    Taneja, R N

    1972-01-01

    A study was carried out among the civil and military population in Poona, India, to determine their knowledge, attitude, and practices in relation to family planning and the fertility rates of women aged 15-44 in the following catagories: 1) total and age specific marital fertility rate; 2) order of birth of the children born during the previous year; 3) average number of living children per couple; and 4) percentage of currently pregnant women. 251 civilian wives and 230 military wives were interviewed. Both total marital fertility rates and age specific marital fertility rates were high among the Service families, due perhaps to the predominance of young people in the military. Most of the live births occurring in the previous year were of the 1-3 order. Similarly, the average number of children per couple was low, only 1.7, although the number of children in completed families (4.4) was not too much lower than in civilian Poona families (4.8) and in India in general (5.5). Nearly 2/3 considered 3 children the ideal, although the desire for boys was intense and could lead couples to seek more than 3 children. Only 10% favored abortion on demand. More Service than civilian families knew about and practiced family planning, though the number practicing was only 27.8%. The most widely known methods were sterilization, the condom, and the IUD. The image of family planning among the civilian population was of family limitation, whereas some Service personnel regarded it as a means of child spacing. Practice of family planning was highest among Junior Commissioned Officers, the more literate, and those in the 30-34 age group. There was a positive correlation between family planning practice and number of living children. It is recommended that fertility statistics on military personnel be maintained annually. Further, as it was discovered that 20% of the military wives were currently pregnant, the family welfare planning staff and maternal health services and the

  8. Size structure and fertility in an Eriocnema fulva Naudin (Melastomataceae) population in Southeastern Brazil.

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    Andrade, P M; Santos, F A M; Martins, F R

    2007-11-01

    Eriocnema fulva Naudin is an endangered perennial herbaceous plant, endemic to Minas Gerais state, Brazil. This study was conducted in the Jambreiro Forest (19 degrees 58' -59'S and 43 degrees 52' -55' W, 800-1100 m altitude). In an attempt to describe the population size structure and its association with individual fertility, fifteen 1 x 1 m contiguous plots were set. We tagged, counted, and measured a total of 260 individuals in 1997, 1998 and 1999. Young individuals with leaf lamina lengths or = 10 cm in length did not reproduce was 2.69%. The highest survival probability of the large-sized individuals confirmed the strong correlation between size and survival. The data indicated that size is important for the fertility of E. fulva, and it may be one of the relevant aspects to be considered for analyses of survival probability. The intraspecific competition, which was indicated by negative correlation between fruit production per size unit and density, can affect fertility, as larger plants had higher fruit production.

  9. Size structure and fertility in an Eriocnema fulva Naudin (Melastomataceae population in Southeastern Brazil

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    PM. Andrade

    Full Text Available Eriocnema fulva Naudin is an endangered perennial herbaceous plant, endemic to Minas Gerais state, Brazil. This study was conducted in the Jambreiro Forest (19° 58' -59'S and 43° 52' -55' W, 800-1100 m altitude. In an attempt to describe the population size structure and its association with individual fertility, fifteen 1 x 1 m contiguous plots were set. We tagged, counted, and measured a total of 260 individuals in 1997, 1998 and 1999. Young individuals with leaf lamina lengths 10 cm in length did not reproduce was 2.69%. The highest survival probability of the large-sized individuals confirmed the strong correlation between size and survival. The data indicated that size is important for the fertility of E. fulva, and it may be one of the relevant aspects to be considered for analyses of survival probability. The intraspecific competition, which was indicated by negative correlation between fruit production per size unit and density, can affect fertility, as larger plants had higher fruit production.

  10. Nonsurgical fertility control for managing free-roaming dog populations: a review of products and criteria for field applications.

    Science.gov (United States)

    Massei, Giovanna; Miller, Lowell A

    2013-11-01

    About 75% of dogs worldwide are free to roam and reproduce, thus creating locally overabundant populations. Problems caused by roaming dogs include diseases transmitted to livestock and humans, predation on livestock, attacks on humans, road traffic accidents, and nuisance behavior. Nonsurgical fertility control is increasingly advocated as more cost-effective than surgical sterilization to manage dog populations and their impact. The aims of this review were to 1) analyze trends in numbers of scientific publications on nonsurgical fertility control for dogs; 2) illustrate the spectrum of fertility inhibitors available for dogs; 3) examine how differences between confined and free-roaming dogs might affect the choice of fertility inhibitors to be used in dog population management; and 4) provide a framework of criteria to guide decisions regarding the use of nonsurgical fertility control for dog population management. The results showed that the 117 articles published between 1982 and 2011 focussed on long-term hormonal contraceptives, such as gonadotropin-releasing hormone agonists, immunocontraceptives, and male chemical sterilants. The number of articles published biennially increased from one to five papers produced in the early 1980s to 10 to 20 in the past decade. Differences between confined dogs and free-roaming dogs include reproduction and survival as well as social expectations regarding the duration of infertility, the costs of sterilization, and the responsibilities for meeting these costs. These differences are likely to dictate which fertility inhibitors will be used for confined or free-roaming dogs. The criteria regarding the use of fertility control for dog population management, presented as a decision tree, covered social acceptance, animal welfare, effectiveness, legal compliance, feasibility, and sustainability. The review concluded that the main challenges for the future are evaluating the feasibility, effectiveness, sustainability, and

  11. [Continuous ecopathological survey. 2. Typology of dairy cattle farms with high and low fertility].

    Science.gov (United States)

    Barnouin, J; Paccard, P; Fayet, J C; Brochart, M; Bouvier, A

    1983-01-01

    Management characteristics were analysed in two groups of dairy herds (20 to 60 cows per herd) during a continuous eco-pathological survey, in relation to high and low fertility. 59.8% of the cows from the eleven high fertility herds were successfully inseminated at first service and 11.4% of the cows inseminated for the first time more than 40 days post-partum required 3 or more services. The corresponding values were 51.1 and 25.6% for the ten low fertility herds. Other reproductive criteria (calving-first service interval, disturbed oestrus cycles), which more depend on the reproduction management, were not different between the two groups. Feeding system greatly varied in the low fertility group. Frequent changes in diet composition, a longer period of "green" forages distribution (crucifers, grass silage) as well as less utilisation of concentrates are some of the reasons which can explain the low fertility. Calving occurred mainly from February to April in low fertility herds, at the transition from winter diets to grazing. Milk production was lower, 4 580 kg per cow and per year vs 5 520 kg for high fertility group. Milk production falls were more frequent and Holstein semen was less used. Tied housing conditions, and higher incidence of Fasciola hepatica and abomasal mematodes characterised low fertility herds; inversely, the clinical pathology appeared to be less frequent in this group. Soil manganese concentration was lower (16.3 ppm) in the low fertility group as compared to the other group (30.9 ppm); this could be explained by less schistose rocks where the low fertility farms are localized. In conclusion, the risk factors associated with low fertility may be attributed to: the composite system of feeding in addition to the use of "green" forages, a lack of proper programming with regards to the season of calving, and the high frequency of parasitic infestations, with special reference to liver fluke.

  12. Fertility and population policy in two counties in China 1980-1991.

    Science.gov (United States)

    Thomas, N H; Mu, A

    2000-01-01

    A survey of women in two highly developed rural counties of China, Sichuan and Jiangsu Provinces, was carried out in late 1991, to gain information about demographic and economic change between 1980 and 1990. Three separate surveys were conducted: the first a questionnaire administered to married women aged 30-39, eliciting information about childbearing and contraception, as well as the social and economic background of the respondents; the second, focus group interviews emphasizing the motivation for childbearing. Official information about the selected villages, townships and counties was also collected. National level data in 1987 show that individual reproductive behaviour in China failed to conform to a universal, effectively implemented, population policy. They imply either a spatial range of policies, or great diversity in the demand for children, or perhaps a combination of both. Such diversity in reproductive behaviour is also found in the study area. The purpose of the analysis was to examine the diversity in reproductive behaviour and contraceptive practice, and to discover whether differentials are influenced by area, or else exist between individuals within areas. If the former, then the explanation may be found in differences in policy formulation and implementation between areas: and if the latter, to demand for children, or else differential application of policy restrictions. The main findings were that: (1) the explanation of the pattern of fertility and contraceptive use is to be found at the individual level (within locations) rather than in policy differences between administrative units; (2) the association between income and number of children is negative, as is that between income and the propensity for uniparous women to remain unsterilized. The theory that privilege may be exercised to gain concessions from birth planning cadres is therefore not supported; (3) ideal family size differentials are largely absent, showing that social

  13. Socioeconomic status and fertility decline

    DEFF Research Database (Denmark)

    Dribe, Martin; Breschi, Marco; Gagnon, Alain

    2017-01-01

    The timings of historical fertility transitions in different regions are well understood by demographers, but much less is known regarding their specific features and causes. In the study reported in this paper, we used longitudinal micro-level data for five local populations in Europe and North...... America to analyse the relationship between socio-economic status and fertility during the fertility transition. Using comparable analytical models and class schemes for each population, we examined the changing socio-economic differences in marital fertility and related these to common theories...... on fertility behaviour. Our results do not provide support for the hypothesis of universally high fertility among the upper classes in pre-transitional society, but do support the idea that the upper classes acted as forerunners by reducing their fertility before other groups. Farmers and unskilled workers...

  14. Fertility/longevity trade-offs under limiting-male conditions in mating populations of Caenorhabditis elegans.

    Science.gov (United States)

    Wu, Deqing; Tedesco, Patricia M; Phillips, Patrick C; Johnson, Thomas E

    2012-10-01

    Evolutionary theories of aging suggest that trade-offs between longevity and fitness should be found under certain conditions. In C. elegans, there is little evidence for the existence of such trade-offs. We asked if fertility/longevity trade-offs exist in populations of randomly mating males and hermaphrodites. We set up a large population of young males and 5-day-old hermaphrodites that were no longer self-fertile. We then allowed them to mate for one day with an equal number young males and then separated hermaphrodites to individual plates and determined daily fertility of individual hermaphrodites. There was a significant negative relationship between late-life fertility and individual longevity. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Populism in High School Textbooks

    Science.gov (United States)

    Peiser, Andrew C.

    1973-01-01

    The purpose of this study was to determine whether one area of United States history--Populism and Populists--is accurately presented in nine widely used current American history high school textbooks. Another objective was to devise a system that could be used to make such a determination for any history text. (Author)

  16. Biotransformation of Organic Waste into High Quality Fertilizer

    DEFF Research Database (Denmark)

    Bryndum, Sofie

    of the inoculated composts neither did inoculation accelerate compost process (Paper II). The main conclusions of the project are (1) increasing the nutrient recycling from agro-industrial waste in Costa Rica by redirection of more waste from other uses into the “fertilizer use” pool is not likely however...... derived nutrient sources, however, generally suffer from three major shortcomings compared to synthetic nutrient sources: (1) the relatively low concentration of nutrients makes them bulky when applied in the required amounts; (2) the immediate plant availability of organically-bound nutrients, e.g. N, P......, with specific focus on reducing nutrient losses during processing and improving bioavailability of nutrients in the final fertilizer product. The project was formulated at two levels of analysis; a contextual-system level and a compost-system level. Costa Rica was used as a contextual case to conduct a nutrient...

  17. Differentially Expressed Genes in Endometrium and Corpus Luteum of Holstein Cows Selected for High and Low Fertility Are Enriched for Sequence Variants Associated with Fertility.

    Science.gov (United States)

    Moore, Stephen G; Pryce, Jennie E; Hayes, Ben J; Chamberlain, Amanda J; Kemper, Kathryn E; Berry, Donagh P; McCabe, Matt; Cormican, Paul; Lonergan, Pat; Fair, Trudee; Butler, Stephen T

    2016-01-01

    Despite the importance of fertility in humans and livestock, there has been little success dissecting the genetic basis of fertility. Our hypothesis was that genes differentially expressed in the endometrium and corpus luteum on Day 13 of the estrous cycle between cows with either good or poor genetic merit for fertility would be enriched for genetic variants associated with fertility. We combined a unique genetic model of fertility (cattle that have been selected for high and low fertility and show substantial difference in fertility) with gene expression data from these cattle and genome-wide association study (GWAS) results in ∼20,000 cattle to identify quantitative trait loci (QTL) regions and sequence variants associated with genetic variation in fertility. Two hundred and forty-five QTL regions and 17 sequence variants associated primarily with prostaglandin F2alpha, steroidogenesis, mRNA processing, energy status, and immune-related processes were identified. Ninety-three of the QTL regions were validated by two independent GWAS, with signals for fertility detected primarily on chromosomes 18, 5, 7, 8, and 29. Plausible causative mutations were identified, including one missense variant significantly associated with fertility and predicted to affect the protein function of EIF4EBP3. The results of this study enhance our understanding of 1) the contribution of the endometrium and corpus luteum transcriptome to phenotypic fertility differences and 2) the genetic architecture of fertility in dairy cattle. Including these variants in predictions of genomic breeding values may improve the rate of genetic gain for this critical trait. © 2016 by the Society for the Study of Reproduction, Inc.

  18. The CFTR Met 470 allele is associated with lower birth rates in fertile men from a population isolate.

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    Gülüm Kosova

    2010-06-01

    Full Text Available Although little is known about the role of the cystic fibrosis transmembrane regulator (CFTR gene in reproductive physiology, numerous variants in this gene have been implicated in etiology of male infertility due to congenital bilateral absence of the vas deferens (CBAVD. Here, we studied the fertility effects of three CBAVD-associated CFTR polymorphisms, the (TGm and polyT repeat polymorphisms in intron 8 and Met470Val in exon 10, in healthy men of European descent. Homozygosity for the Met470 allele was associated with lower birth rates, defined as the number of births per year of marriage (P = 0.0029. The Met470Val locus explained 4.36% of the phenotypic variance in birth rate, and men homozygous for the Met470 allele had 0.56 fewer children on average compared to Val470 carrier men. The derived Val470 allele occurs at high frequencies in non-African populations (allele frequency = 0.51 in HapMap CEU, whereas it is very rare in African population (Fst = 0.43 between HapMap CEU and YRI. In addition, haplotypes bearing Val470 show a lack of genetic diversity and are thus longer than haplotypes bearing Met470 (measured by an integrated haplotype score [iHS] of -1.93 in HapMap CEU. The fraction of SNPs in the HapMap Phase2 data set with more extreme Fst and iHS measures is 0.003, consistent with a selective sweep outside of Africa. The fertility advantage conferred by Val470 relative to Met470 may provide a selective mechanism for these population genetic observations.

  19. Fertility preservation in the male pediatric population: factors influencing the decision of parents and children.

    Science.gov (United States)

    Wyns, C; Collienne, C; Shenfield, F; Robert, A; Laurent, P; Roegiers, L; Brichard, B

    2015-09-01

    How can the decision process for fertility preservation (FP) in adolescents and prepubertal boys be improved based on patient and parent feelings about FP counseling? The content of information given to patients and parents and hope for future parenthood appeared to positively impact on the decision to preserve fertility in the pediatric population and, therefore, deserves special attention to improve FP care. A vast body of literature on adult cancer patients shows that reproductive capacity is a major quality-of-life issue. Patients also have a strong desire to be informed of available FP options with a view to future parenthood of their own genetic child, considering that parents were able to make an informed and voluntary decision for their prepubertal sons despite the heavy emotional burden at the time of diagnosis, there is so far very limited information on patient expectations regarding FP. A lack of awareness often equates to suboptimal care by oncologists and FP specialists, and poor access to FP, therefore improving knowledge and identifying the expectations of pediatric patients and their parents are crucial for optimizing multidisciplinary collaborative care pathways (MCCPs), including counseling and access to FP methods, in the youngest population. A questionnaire survey was posted to an eligible population between May 2005 and May 2013. A total of 348 prepubertal boys and adolescents aged 0-18 years, diagnosed with cancer in a university hospital setting, were eligible. Three different questionnaires for two age groups of children (parents were established based on information from focus groups. Questions were subsequently reviewed by the institutional ethics board before being sent. Of the 348 eligible patients, 44 died and 14 were lost to follow-up. Thus, 290 patients (77 aged 12-18 years and 213 aged children. FP acceptance rates were, respectively, 74 and 78.6% for boys aged parents appeared to positively impact on the decision to preserve

  20. Impaired Fertility Associated with Subclinical Hypothyroidism and Thyroid Autoimmunity: The Danish General Suburban Population Study

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    Anne-Dorthe Feldthusen

    2015-01-01

    Full Text Available Introduction. The aim of this study was to estimate the significance of TSH, thyroid peroxidase antibody (TPOAb, and mild (subclinical hypothyroidism in women from The Danish General Suburban Population Study (GESUS on the number of children born, the number of pregnancies, and the number of spontaneous abortions. Methods. Retrospective cross sectional study of 11254 women participating in GESUS. Data included biochemical measurements and a self-administrated questionnaire. Results. 6.7% had mild (subclinical hypothyroidism and 9.4% prevalent hypothyroidism. In women with mild hypothyroidism TPOAb was significantly elevated and age at first child was older compared to controls. TSH and TPOAb were negatively linearly associated with the number of children born and the number of pregnancies in the full cohort in age-adjusted and multiadjusted models. TSH or TPOAb was not associated with spontaneous abortions. Mild (subclinical hypothyroidism was associated with a risk of not having children and a risk of not getting pregnant in age-adjusted and multiadjusted models. Prevalent hypothyroidism was not associated with the number of children born, the number of pregnancies, or spontaneous abortions. Conclusion. Impaired fertility is associated with TSH, TPOAb, and mild (subclinical hypothyroidism in a Danish population of women.

  1. Impaired Fertility Associated with Subclinical Hypothyroidism and Thyroid Autoimmunity: The Danish General Suburban Population Study

    Science.gov (United States)

    Pedersen, Palle L.; Larsen, Jacob

    2015-01-01

    Introduction. The aim of this study was to estimate the significance of TSH, thyroid peroxidase antibody (TPOAb), and mild (subclinical) hypothyroidism in women from The Danish General Suburban Population Study (GESUS) on the number of children born, the number of pregnancies, and the number of spontaneous abortions. Methods. Retrospective cross sectional study of 11254 women participating in GESUS. Data included biochemical measurements and a self-administrated questionnaire. Results. 6.7% had mild (subclinical) hypothyroidism and 9.4% prevalent hypothyroidism. In women with mild hypothyroidism TPOAb was significantly elevated and age at first child was older compared to controls. TSH and TPOAb were negatively linearly associated with the number of children born and the number of pregnancies in the full cohort in age-adjusted and multiadjusted models. TSH or TPOAb was not associated with spontaneous abortions. Mild (subclinical) hypothyroidism was associated with a risk of not having children and a risk of not getting pregnant in age-adjusted and multiadjusted models. Prevalent hypothyroidism was not associated with the number of children born, the number of pregnancies, or spontaneous abortions. Conclusion. Impaired fertility is associated with TSH, TPOAb, and mild (subclinical) hypothyroidism in a Danish population of women. PMID:26351582

  2. Women with celiac disease present with fertility problems no more often than women in the general population.

    Science.gov (United States)

    Dhalwani, Nafeesa N; West, Joe; Sultan, Alyshah Abdul; Ban, Lu; Tata, Laila J

    2014-12-01

    Studies have associated infertility with celiac disease. However, these included small numbers of women attending infertility specialist services and subsequently screened for celiac disease, and therefore may not have been representative of the general population. We performed a large population-based study of infertility and celiac disease in women from the United Kingdom. We identified 2,426,225 women with prospective UK primary care records between 1990 and 2013 during their child-bearing years from The Health Improvement Network database. We estimated age-specific rates of new clinically recorded fertility problems among women with and without diagnosed celiac disease. Rates were stratified by whether celiac disease was diagnosed before the fertility problem or afterward and compared with rates in women without celiac disease using Poisson regression, adjusting for sociodemographics, comorbidities, and calendar time. Age-specific rates of new clinically recorded fertility problems in 6506 women with celiac disease were similar to the rates in women without celiac disease (incidence rate ratio, 1.12; 95% confidence interval, 0.88-1.42 among women age 25-29 years). Rates of infertility among women without celiac disease were similar to those of women with celiac disease before and after diagnosis. However, rates were 41% higher among women diagnosed with celiac disease when they were 25-29 years old, compared with women in the same age group without celiac disease (incidence rate ratio, 1.41; 95% confidence interval, 1.03-1.92). Women with celiac disease do not have a greater likelihood of clinically recorded fertility problems than women without celiac disease, either before or after diagnosis, except for higher reports of fertility problems between 25-39 years if diagnosed with CD. These findings should assure most women with celiac disease that they do not have an increased risk for fertility problems. Copyright © 2014 AGA Institute. Published by Elsevier

  3. Labor and Population Program. U.S. Abortion Policy and Fertility

    National Research Council Canada - National Science Library

    2000-01-01

    .... What are the links between changes in abortion policy and fertility in the United States? Jacob Alex Klerman explores this question through an analysis of birth statistics by race, age, state, and parity...

  4. Fertilization variants effect in the incidence and populational fluctuation of the true bugs complex (Hemipterous: Pentatomidae in common bean

    Directory of Open Access Journals (Sweden)

    Yordanys Ramos González

    2016-03-01

    Full Text Available This work was done in the “Panchita Orchard” Township Quemado de Guines, province of Villa Clara from September 2010 to December 2011. Was to determine the effect of fertilization have some variations in behavior and incidence of associated pentatomid common bean. Varieties were planted two different colored heads (1 red and 1 white in random blocks on a Brown soil Carbonated Fluffy. The input of the first adults phenophase occurred in R2 and R3 peak in population with 28.8% of the Pentatomidae detected. In the two varieties studied, Rhizobium fertilization showed the best effects in reducing insect and the rate and degree of involvement, the opposite of what happened with the urea, which were equal to the control population levels, but higher affectations. The pentatomids presented similar preference for the two varieties since no differences in the parameters.

  5. Fertility of tall girls treated with high-dose estrogen, a dose-response relationship

    NARCIS (Netherlands)

    A.E.J. Hendriks (Emile); S.L.S. Drop (Stenvert); J.S.E. Laven (Joop); A.M. Boot (Annemieke)

    2012-01-01

    textabstractContext: High-dose estrogen treatment to reduce final height of tall girls increases their risk for infertility in later life. Objective: The aim was to study the effect of estrogen dose on fertility outcome of these women. Design/Setting: We conducted a retrospective cohort study of

  6. Fertility of Tall Girls Treated with High-Dose Estrogen, a Dose-Response Relationship

    NARCIS (Netherlands)

    Hendriks, A. E. J.; Drop, S. L. S.; Laven, J. S. E.; Boot, A. M.

    Context: High-dose estrogen treatment to reduce final height of tall girls increases their risk for infertility in later life. Objective: The aim was to study the effect of estrogen dose on fertility outcome of these women. Design/Setting: We conducted a retrospective cohort study of university

  7. Fertility and pregnancy: common concerns of the aging cystic fibrosis population.

    Science.gov (United States)

    Sueblinvong, Viranuj; Whittaker, Laurie A

    2007-06-01

    Due to dramatically improved survival, cystic fibrosis (CF) is now considered a chronic disease of adults. Many men and women who have CF are interested in starting families and have questions regarding fertility and pregnancy, making discussion of these issues important in routine CF care. This article addresses key issues of fertility in men and women who have CF and discusses pregnancy, including maternal and fetal outcomes, highlighting advances over the last decade.

  8. Changes in Fertility at the Population Level in the Era of ART in Rural Malawi.

    Science.gov (United States)

    McLean, Estelle; Price, Alison; Chihana, Menard; Kayuni, Ndoliwe; Marston, Milly; Koole, Olivier; Zaba, Basia; Crampin, Amelia

    2017-08-01

    HIV reduces fertility through biological and social pathways, and antiretroviral treatment (ART) can ameliorate these effects. In northern Malawi, ART has been available since 2007 and lifelong ART is offered to all pregnant or breastfeeding HIV-positive women. Using data from the Karonga Health and Demographic Surveillance Site in Malawi from 2005 to 2014, we used total and age-specific fertility rates and Cox regression to assess associations between HIV and ART use and fertility. We also assessed temporal trends in in utero and breastfeeding HIV and ART exposure among live births. From 2005 to 2014, there were 13,583 live births during approximately 78,000 person years of follow-up of women aged 15-49 years. The total fertility rate in HIV-negative women decreased from 6.1 [95% confidence interval (CI): 5.5 to 6.8] in 2005-2006 to 5.1 (4.8-5.5) in 2011-2014. In HIV-positive women, the total fertility rate was more stable, although lower, at 4.4 (3.2-6.1) in 2011-2014. In 2011-2014, compared with HIV-negative women, the adjusted (age, marital status, and education) hazard ratio was 0.7 (95% CI: 0.6 to 0.9) and 0.8 (95% CI: 0.6 to 1.0) for women on ART for at least 9 months and not (yet) on ART, respectively. The crude fertility rate increased with duration on ART up to 3 years before declining. The proportion of HIV-exposed infants decreased, but the proportion of ART-exposed infants increased from 2.4% in 2007-2010 to 3.5% in 2011-2014. Fertility rates in HIV-positive women are stable in the context of generally decreasing fertility. Despite a decrease in HIV-exposed infants, there has been an increase in ART-exposed infants.

  9. Heritability and fitness correlates of personality in the Ache, a natural-fertility population in Paraguay.

    Science.gov (United States)

    Bailey, Drew H; Walker, Robert S; Blomquist, Gregory E; Hill, Kim R; Hurtado, A Magdalena; Geary, David C

    2013-01-01

    The current study assessed the heritability of personality in a traditional natural-fertility population, the Ache of eastern Paraguay. Self-reports (n = 110) and other-reports (n = 66) on the commonly used Big Five Personality Inventory (i.e., extraversion, agreeableness, conscientiousness, neuroticism, openness) were collected. Self-reports did not support the Five Factor Model developed with Western samples, and did not correlate with other-reports for three of the five measured personality factors. Heritability was assessed using factors that were consistent across self- and other-reports and factors assessed using other-reports that showed reliabilities similar to those found in Western samples. Analyses of these items in combination with a multi-generation pedigree (n = 2,132) revealed heritability estimates similar to those found in most Western samples, although we were not able to separately estimate the influence of the common environment on these traits. We also assessed relations between personality and reproductive success (RS), allowing for a test of several mechanisms that might be maintaining heritable variation in personality. Phenotypic analyses, based largely on other-reports, revealed that extraverted men had higher RS than other men, but no other dimensions of personality predicted RS in either sex. Mothers with more agreeable children had more children, and parents mated assortatively on personality. Of the evolutionary processes proposed to maintain variation in personality, assortative mating, selective neutrality, and temporal variation in selection pressures received the most support. However, the current study does not rule out other processes affecting the evolution and maintenance of individual differences in human personality.

  10. Heritability and Fitness Correlates of Personality in the Ache, a Natural-Fertility Population in Paraguay

    Science.gov (United States)

    Bailey, Drew H.; Walker, Robert S.; Blomquist, Gregory E.; Hill, Kim R.; Hurtado, A. Magdalena; Geary, David C.

    2013-01-01

    The current study assessed the heritability of personality in a traditional natural-fertility population, the Ache of eastern Paraguay. Self-reports (n = 110) and other-reports (n = 66) on the commonly used Big Five Personality Inventory (i.e., extraversion, agreeableness, conscientiousness, neuroticism, openness) were collected. Self-reports did not support the Five Factor Model developed with Western samples, and did not correlate with other-reports for three of the five measured personality factors. Heritability was assessed using factors that were consistent across self- and other-reports and factors assessed using other-reports that showed reliabilities similar to those found in Western samples. Analyses of these items in combination with a multi-generation pedigree (n = 2,132) revealed heritability estimates similar to those found in most Western samples, although we were not able to separately estimate the influence of the common environment on these traits. We also assessed relations between personality and reproductive success (RS), allowing for a test of several mechanisms that might be maintaining heritable variation in personality. Phenotypic analyses, based largely on other-reports, revealed that extraverted men had higher RS than other men, but no other dimensions of personality predicted RS in either sex. Mothers with more agreeable children had more children, and parents mated assortatively on personality. Of the evolutionary processes proposed to maintain variation in personality, assortative mating, selective neutrality, and temporal variation in selection pressures received the most support. However, the current study does not rule out other processes affecting the evolution and maintenance of individual differences in human personality. PMID:23527163

  11. The demography and population genomics of evolutionary transitions to self-fertilization in plants.

    Science.gov (United States)

    Barrett, Spencer C H; Arunkumar, Ramesh; Wright, Stephen I

    2014-08-05

    The evolution of self-fertilization from outcrossing has occurred on numerous occasions in flowering plants. This shift in mating system profoundly influences the morphology, ecology, genetics and evolution of selfing lineages. As a result, there has been sustained interest in understanding the mechanisms driving the evolution of selfing and its environmental context. Recently, patterns of molecular variation have been used to make inferences about the selective mechanisms associated with mating system transitions. However, these inferences can be complicated by the action of linked selection following the transition. Here, using multilocus simulations and comparative molecular data from related selfers and outcrossers, we demonstrate that there is little evidence for strong bottlenecks associated with initial transitions to selfing, and our simulation results cast doubt on whether it is possible to infer the role of bottlenecks associated with reproductive assurance in the evolution of selfing. They indicate that the effects of background selection on the loss of diversity and efficacy of selection occur rapidly following the shift to high selfing. Future comparative studies that integrate explicit ecological and genomic details are necessary for quantifying the independent and joint effects of selection and demography on transitions to selfing and the loss of genetic diversity. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  12. Effect of high and low antral follicle count in pubertal beef heifers on in vitro fertilization (IVF)

    Science.gov (United States)

    Pubertal heifers can be classified between those with high (= 25) and low (= 15) antral follicle counts (AFC). The objective of this study was to determine oocyte development and maturation (e.g., fertility) in an in vitro fertilization (IVF) system for high and low AFC heifers. From a pool of 120...

  13. HIGH INCIDENCE OF POLYSPERMIC FERTILIZATION IN BOVINE OOCYTES MATURED IN VITRO AFTER CRYOTOP VITRIFICATION.

    Science.gov (United States)

    Hwang, In-Sul; Kwon, Dae-Jin; Im, Gi-Sun; Tashima, Kazuya; Hochi, Shinichi; Hwang, Seongsoo

    2016-01-01

    Vitrification with the Cryotop device is the most promising technique for oocyte cryopreservation, but the high post-warming morphological survival of bovine oocytes does not guarantee high developmental competence after in vitro fertilization (IVF). This study was designed to examine achievement of normal fertilization in bovine oocytes vitrified-warmed with the Cryotop device. Oocytes were matured in vitro and vitrified-warmed after complete removal of the cumulus layers. Distribution of cortical granules (CGs) was assessed by Lens culinaris agglutinin (LCA) lectin staining. Ten hours after IVF, presumptive zygotes were analyzed for pronuclear formation. Day-8 blastocysts were harvested and stained with Hoechst-33342 for total cell counting. Both yield and mean cell number of the blastocysts were impaired by Cryotop vitrification. Incidence of polyspermic fertilization was three-times higher in vitrified oocytes compared to fresh oocytes. No difference in CG distribution was found between vitrified and fresh oocytes. Polyspermic fertilization induced in vitrified-warmed bovine oocytes may be one of the possible causes responsible for their low developmental potential.

  14. Parental Infertility, Fertility Treatment, and Childhood Epilepsy: A Population-Based Cohort Study.

    Science.gov (United States)

    Kettner, Laura O; Ramlau-Hansen, Cecilia H; Kesmodel, Ulrik S; Bay, Bjørn; Matthiesen, Niels B; Henriksen, Tine B

    2016-09-01

    A few studies have indicated an increased risk of epilepsy in children conceived by fertility treatment possibly due to characteristics of the infertile couple rather than the treatment. We therefore aimed to investigate the association between parental infertility, fertility treatment, and epilepsy in the offspring, including the subtypes of epilepsy; idiopathic generalised epilepsy and focal epilepsy. This cohort included all pregnancies resulting in liveborn singletons from the Aarhus Birth Cohort, Denmark (1995-2013). Information on time to pregnancy and fertility treatment was obtained from pregnancy questionnaires in early pregnancy. Children developing epilepsy were identified from the Danish National Patient Register and the Danish National Prescription Registry until 2013. Data were analysed using Cox proportional hazards regression adjusted for potential confounders. A total of 60 440 pregnancies were included, and 0.8% of the children developed epilepsy.The primary analyses showed no association between parental infertility or fertility treatment, and the overall risk of childhood epilepsy (hazard rate ratios (HRs); 95% confidence intervals (CIs): 1.08 (0.73, 1.60) and 1.04 (0.71, 1.52)). In secondary analyses, both parental infertility and fertility treatment were associated with an increased risk of idiopathic generalised epilepsy (HRs and 95% CIs: 2.25 (1.10, 4.58) and 2.45 (1.26, 4.75)). No association was seen for focal epilepsy. Parental infertility or fertility treatment was not associated with an overall risk of childhood epilepsy. Parental infertility may be associated with an increased risk of idiopathic generalised epilepsy; a subtype of epilepsy believed to be of genetic origin. © 2016 John Wiley & Sons Ltd.

  15. Determinants of fertility in Ethiopia | Ayele | African Health Sciences

    African Journals Online (AJOL)

    Background: The most important elements to determine the rate of population growth is fertility. Fertility is the main element to affect the welfare of mother. The survival of a child can be affected by high fertility and shorter birth intervals. Methods: For this study, the linear mixed model was used to determine factors affecting ...

  16. Are educators at high risk of sub-fertility? A multicenter study.

    Science.gov (United States)

    Perros, Gerasimos; Tzonis, Panagiotis; Tsilivakos, Vasilis; Gerofotis, Antonios; Dalavitsou, Vasiliki; Vassilaki, Athina; Keramitsoglou, Theodora; Papaioannou, Dimitris; Moschandreou, Dimitra; Kontopoulou-Antonopoulou, Virginia; Daniilidis, Michail; Varla-Leftherioti, Marighoula

    2011-04-01

    A high percentage of women schoolteachers having fertility problems were observed by three independent teams. Expected percentage of educators was calculated in 4650 sub-fertile women and 2,062,891 women at reproductive age. To explore the possibility that schoolteachers' contact with childhood viral infections results in alterations of peripheral blood natural killer (NK) cells, a multiple linear regression analysis for profession, age, difficulty to conceive, number of abortions/implantation failures (predictor variables) was performed in childless educators (210) and housewives (184). The difference between observed and expected percentage of sub-fertile schoolteachers was statistically significant (17.6% vs 6.86%, P < 0.0001). The mean percentage of PB NK cells was slightly higher in educators compared to housewives (12.48% vs 11.56%, P = 0.10), and the multiple linear regression analysis revealed that the profession (schoolteacher or not) was the only predictive variable for higher NK% values (P = 0.044). Teachers' sub-fertility appears as an 'occupational disease'. Τhe possibility that results from their exposure to childhood viral infections has to be further explored. © 2010 John Wiley & Sons A/S.

  17. Fertility After Treatment With High Dose Melphalan in Women With Acute Myelogenous Leukemia.

    Science.gov (United States)

    Even-Or, Ehud; Ben-Haroush, Avi; Yahel, Anat; Yaniv, Isaac; Stein, Jerry

    2016-02-01

    High-dose melphalan (HDM) is an integral component of conditioning regimens for autologous and allogeneic hematopoietic stem cell transplantation for patients with malignant and non-malignant diseases. The gonadotoxic effects of HDM are often obscured by previous or concurrent administration of alkylating agents. From April 1996 to January 2006 our acute myeloid leukemia treatment regimen included induction and consolidation therapy with cytosine arabinoside, anthracyclines and etoposide, followed by HDM and autologous stem cell infusion. We explored gonadal function in surviving female patients so treated, who represent a unique group of patients exposed to HDM as a single gonadotoxic agent. The fertility assessment included a questionnaire, blood tests for luteinizing hormone, follicle stimulating hormone and anti mullerian hormone (AMH), and a gynecological ultrasound exam for antral follicular count (AFC). Eight female survivors participated. Although fertility assessment showed considerable damage to ovarian reserve in all participants, four of the eight female survivors conceived and bore children without medical intervention. In this cohort, HDM treatment reduced fertility potential but did not preclude fecundity. Early referral to a fertility clinic and long term follow-up including serial measurements of AMH levels and AFC for female patients receiving HDM are recommended. © 2015 Wiley Periodicals, Inc.

  18. A 660-Kb Deletion with Antagonistic Effects on Fertility and Milk Production Segregates at High Frequency in Nordic Red Cattle

    DEFF Research Database (Denmark)

    Kadri, Naveen Kumar; Sahana, Goutam; Charlier, Carole

    The spectacular increase in productivity of dairy cattle has been accompanied by a decline in fertility. It is assumed that this reduction is due to the negative energy balance of high producing cows. We herein describe the dissection of a fertility QTL in Nordic Red cattle to a 660-Kb deletion...

  19. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman

    2016-01-01

    with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N...... in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest...... carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground...

  20. An Evaluation of the Pearsonian Type I Curve of Fertility for Aboriginal Populations in Canada, 1996 to 2001

    Directory of Open Access Journals (Sweden)

    Verma, Ravi B.P.

    2008-01-01

    Full Text Available EnglishIn 2005, Statistics Canada published new projections of the Aboriginal populations (NorthAmerican Indians, Métis, and Inuit in Canada, the provinces and territories from 2001 to2017. To derive the number of births in these projections, the age-specific fertility rates weresimulated by fitting the Pearsonian Type I curve using the projected fertility parameters: totalfertility rates, mean ages of fertility, and modal ages of fertility. For the base period 1996 to2001, the parameters were estimated from the age-specific fertility rates derived from the 2001Census, using the “own-children method.” This paper evaluates the goodness of fit betweenthe age-specific fertility rates developed by the Type I curve and the estimated age-specificfertility rates for Aboriginal identity groups for the period 1996 to 2001 for Canada and forhigh and low fertility regions. Tests of validity of the Type I curve indicate that this method isappropriate for estimating/projecting the number of births for the Aboriginal populations.Key Words: Aboriginal populations, North American Indians, Métis, Inuit, own-childrenmethod, Pearsonian type I curve.FrenchEn 2005, Statistique Canada publiait de nouvelles projections des populations autochtones(Indiens de l’Amérique du Nord, Métis et Inuit au Canada, les provinces et les territoires de2001 à 2017. Afin de calculer le nombre de naissances dans ces projections, les taux de féconditépar âge ont été simulés en ajustant la courbe de Type I de Pearson selon les paramètresde fécondité projetés: l’indice synthétique de fécondité, l’âge moyen à l’accouchement et l’âgemodal à l’accouchement. Pour la période de base de 1996 à 2001, ces paramètres ont étéestimés selon les taux de fécondité par âge générés par la méthode du « décompte des enfantsau foyer » avec les données des enfants âgés de 0 à 4 ans et les femmes dans le groupe d’âgede 15 à 49 ans provenant du

  1. An investigation of the unexpectedly high fertility of secular, native-born Jews in Israel.

    Science.gov (United States)

    Okun, Barbara S

    2016-07-01

    Secular, native-born Jews in Israel enjoy the socio-economic status of many affluent populations living in other democratic countries, but have above-replacement period and cohort fertility. This study revealed a constellation of interrelated factors which together characterize the socio-economic, cultural, and political environment of this fertility behaviour and set it apart from that of other advanced societies. The factors are: a combination of state and family support for childbearing; a dual emphasis on the social importance of women's employment and fertility; policies that support working mothers within a conservative welfare regime; a family system in which parents provide significant financial and caregiving aid to their adult children; relatively egalitarian gender-role attitudes and household behaviour; the continuing importance of familist ideology and of marriage as a social institution; the role of Jewish nationalism and collective behaviour in a religious society characterized by ethno-national conflict; and a discourse which defines women as the biological reproducers of the nation. Supplementary material for this article is available at: http://dx.doi.org/10.1080/00324728.2016.1195913.

  2. Factors affecting the fertility of high producing dairy herds in northeastern Spain.

    Science.gov (United States)

    García-Ispierto, I; López-Gatius, F; Santolaria, P; Yániz, J L; Nogareda, C; López-Béjar, M

    2007-02-01

    Infertility has been often correlated to a rising milk yield in high producing dairy cattle. The aim of the present study was to evaluate, using logistic regression procedures, the effects of several management indicators on the fertility of four dairy herds in northeastern Spain. Data derived from 10,965 artificial insemination (AI). The factors examined were: herd, milking frequency (three versus two milkings per day), lactation number, previous twinning and disorders such as placenta retention and pyometra, milk production at AI, the inseminating bull, season (warm versus cool period) and year effects, AI technician and repeat breeding syndrome (cows undergoing four or more AI). Our findings indicated no effects on fertility of the herd, year of AI, previous twining, placenta retention and pyometra and milk production at AI. Based on the odds ratios, the likelihood of pregnancy decreased: in cows milked three times per day (by a factor of 0.62); for each one unit increase in lactation number (by a factor of 0.92); for inseminations performed during the warm period (by a factor of 0.67); in repeat breeder cows (by a factor of 0.73); and when 3 of the 45 inseminating bulls included in the study were used (by factors of 0.35, 0.43 and 0.44, respectively). Of the 13 AI technicians participating in the study, 3 were related to a fertility rate improved by odds ratios of 1.86, 1.84 and 1.30, respectively, whereas 2 technicians gave rise to fertility rates reduced by odds ratios of 0.64 and 0.49, respectively. Under our study conditions, management practices were able to compensate for the effects of previous twining and reproductive disorders such as placenta retention and pyometra. However, fertility was significantly affected by the factors milking frequency, AI technician, inseminating bull, repeat breeding syndrome, lactation number and AI season.

  3. The Progamic Phase in High-Mountain Plants: From Pollination to Fertilization in the Cold

    Directory of Open Access Journals (Sweden)

    Gerlinde Steinacher

    2013-06-01

    Full Text Available In high-mountains, cold spells can occur at any time during the growing season and plants may be covered with snow for several days. This raises the question to what extent sexual processes are impaired by low temperatures. We tested pollen performance and fertilization capacity of high-mountain species with different elevational distribution in the European Alps (Cerastium uniflorum, Gentianella germanica, Ranunculus glacialis, R. alpestris, Saxifraga bryoides, S. caesia, S. moschata during simulated cold snaps in the laboratory. Plants were exposed to 0 °C (the temperature below the snow for 12, 36, 60 and 84 h. In S. caesia, the experiment was verified in situ during a cold snap. Sexual processes coped well with large temperature differences and remained functional at near-freezing temperatures for a few days. During the cooling-down phase a high percentage (67–97% of pollen grains germinated and grew tubes into the style. At zero degrees, tube growth continued slowly both in the laboratory and in situ below the snow. Fertilization occurred in up to 100% of flowers in the nival species and in G. germanica, but was strongly delayed or absent in the alpine species. During rewarming, fertilization continued. Overall, progamic processes in high-mountain plants appear fairly robust toward weather extremes increasing the probability of successful reproduction.

  4. Fertility-related pensions and fertility disincentives

    OpenAIRE

    Luca Gori; Luciano Fanti

    2008-01-01

    Since recent studies have argued that a pro-natalist effect could be obtained by introducing fertility-related pension systems for contrasting, especially in European countries, the plague of below-replacement fertility and the resulting problem of financing the widespread pay-as-you-go (PAYG) pension benefits, we built up an overlapping generations (OLG) general equilibrium model with endogenous fertility, to investigate whether and how a fertility-related pension reform increases population...

  5. In high school and pregnant: the importance of educational and fertility expectations for subsequent outcomes.

    Science.gov (United States)

    Yakusheva, Olga

    2011-01-01

    This study uses the High School and Beyond data (1980–1992) to examine the importance of educational and fertility expectations in explaining the achievement gap of adolescent mothers for over 5,500 young women from different socioeconomic backgrounds. Using a non-parametric local propensity score regression, the study finds that the economic disadvantage associated with having a child in high school is particularly large in poor socioeconomic environments; however, this disadvantage is a result of preexisting differences in the educational and fertility expectations and is not because of a diminished capacity of the socioeconomic environment to mediate the effect of an unplanned childbirth. The findings suggest that childcare assistance and other policies designed to alleviate the burden of child rearing for young mothers of low means may not produce the desired improvement in their subsequent educational and labor market outcomes. A much earlier policy intervention with a focus on fostering young women's outlook for the future is needed.

  6. Biomass Increase in Plankton Populations Induced by Organic Fertilizers Applied during the Reproduction of Common Carp

    Directory of Open Access Journals (Sweden)

    Levente Vass

    2012-10-01

    Full Text Available Artificial fertilization of nursery ponds used for nursing postlarvae to fry is a common procedure used in hatcheries to enchance productivity. A 2 ha nursery pond at the Martinesti hatchery was fertilized with 500 kg fermented manure to stimulate phytoplankton, and consequently zooplankton production. A sharp rise in nutrient levels was imminent. Nitrate and phosphate levels has rised tenfold from 0.5 to 2 and 5 mg l-1, respectively from 0.05 to 0.5 mg l-1. Altough nutrient levels kept rising, phytoplankton biomass remained steady, then fell from 0.6 to 0.1 g m-3, while zooplankton biomass has increased from 5 to 14 and 64 g m-3 during the first 4 weeks of postlarval developement.

  7. [Occupational exposure and male fertility. Results of an Italian multicenter study in an exposed population].

    Science.gov (United States)

    Petrelli, G; Lauria, L; Figà-Talamanca, I

    2001-01-01

    It was believed that occupational exposure to several toxic agents could negatively affect male fertility. This paper reports the results of a study on the fertility of couples in whom the man was occupationally exposed to three different toxics: metals, solvents and pesticides, having effects on reproduction. Fertility was evaluated during the time that elapsed between attempting and achieving the first pregnancy of the couple (time to pregnancy--TTP). Exposure to occupational risks during the period preceding conception was defined on the basis of data collected from 153 workers of a mint (exposed to metal and solvents), 322 agricultural workers licensed to handle pesticides and 127 greenhouse workers. Comparing the groups exposed during the conception period with comparable non-exposed groups, we found a slight delay in conception among couples with male exposure to metals (OR = 1.3; 95% CI 0.5-3.6), to solvents (OR = 1.7; 95% CI 0.6-4.6) and to pesticides among greenhouse workers (OR = 1.6; 95% CI 0.8-3.1 for the moderately exposed and OR = 2.4; 95% CI 1.2-5.1 for the heavily exposed). No increase in the risk of conception delay was observed in agricultural workers with generic exposure to pesticides. The results of this study suggest that the workers exposed to metals and solvents and greenhouse workers exposed to pesticides experienced a delay in conception at the time of their wives' first pregnancy.

  8. Sexual maturation and fertility issues among high school males in rural Embu, Kenya.

    Science.gov (United States)

    Oniang'o, R K; Rogo, K O

    1989-01-01

    A total of 198 high school boys ranging in age from 16 to 20 years in Embu District were interviewed on various fertility-related issues. The study sought information on reproduction-knowledge, attitudes and practices regarding this and other issues. Results show the young men to have considerable knowledge about reproduction with many of them being precise as to when they attained various reproductive milestones. More that 90% of the respondents had experienced 1st coitus by 15-17 years of age. The respondents expressed the wish to have Family Life Education taught in schools. Indeed, many of them learnt about fertility on their own. It is recommended that a way be found of imparting knowledge and instilling moral values into the youth and providing better guidance on these major life issues. (Author's).

  9. A population-based survey on family intentions and fertility awareness in women and men in the United Kingdom and Denmark

    DEFF Research Database (Denmark)

    Vassard, Ditte; Lallemant, Camille; Nyboe Andersen, Anders

    2016-01-01

    -related decrease in female fertility, most desired having children at an age when female fertility has declined. Women who were not sufficiently aware of the impact of advanced age were significantly more likely to have their first child at a higher age. There is a need for developing educational programs......BACKGROUND: Across several European countries family formation is increasingly postponed. The aims of the study were to investigate the desire for family building and fertility awareness in the UK and Denmark. METHODS: A population-based internet survey was used among women (n = 1,000) and men (n...... = 237) from the UK (40%) and Denmark (60%). Data covered socio-demographics, family formation, and awareness of female age-related fertility. Data analysis used descriptive statistics and logistic regression analysis for studying associations between low fertility awareness and desired family formation...

  10. Ectopic pregnancy rates after in vitro fertilization: a look at the donor egg population.

    Science.gov (United States)

    Rosman, Elana R; Keegan, Debbra A; Krey, Lewis; Liu, Mengling; Licciardi, Frederick; Grifo, Jamie A

    2009-11-01

    In an 8-year review of ectopic pregnancy (EP) rates in donor egg recipients and standard patients undergoing in vitro fertilization-embryo transfer (IVF-ET) at a large university-based program, we report an EP rate of 0.6% in donor egg recipients and 0.9% in standard IVF patients, a difference that is not statistically significant. Donor egg recipients were found to have a significantly lower incidence of tubal disease compared with standard IVF patients; however, tubal disease was not found to be an independent risk factor for EP in our practice, perhaps owing to aggressive management of tubal disease.

  11. Global transcriptional expression in ovarian follicles from Tsaiya ducks (Anas platyrhynchos) with a high-fertilization rate.

    Science.gov (United States)

    Wu, Shyh-Jong; Cheng, Yu-Shin; Liu, Hsiao-Lung; Wang, Hsing-He; Huang, Hsiu-Lin

    2016-05-01

    Novel candidates for biomarkers of a high-fertilization rate were identified here through global transcriptional profiling of ovarian follicles. Some other differentially expressed candidate genes were first noted to influence animal reproduction in our previous cDNA microarray analysis and are now recognized as markers for marker-assisted selection. In the present study, we compared gene expression in ovarian follicles from animals with high- and low-fertilization rates using an oligonucleotide array. On the basis of a fold change of greater than 1.2 and less than -1.2, a difference of >100 Affymetrix arbitrary units between the two groups, and a P value of less than 0.05, 47 genes were found to be associated with fertilization rate. GOEAST and MetaCore software were further used to identify the functional categories of genes that were differentially expressed. Then, we focused on three interesting genes associated with a high-fertilization rate: one of these genes was discovered to participate in signaling pathways of fertilization, and two genes take roles in lipid metabolism. An oligonucleotide array showed that the levels of orthodenticle homeobox 2 (OTX2) and lecithin:cholesterol acyltransferase (LCAT) gene expression were 1.62-fold and 1.95-fold higher in the high-fertilization rate group than in the low-fertilization rate group, respectively (P fertilization rate group, with a difference of 2.31-fold (P fertilization rates in ovarian follicles. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Determinants of fertility in Ethiopia.

    Science.gov (United States)

    Ayele, Dawit Getnet

    2015-06-01

    The most important elements to determine the rate of population growth is fertility. Fertility is the main element to affect the welfare of mother. The survival of a child can be affected by high fertility and shorter birth intervals. For this study, the linear mixed model was used to determine factors affecting fertility status of women in Ethiopia. The 2011 Ethiopian demographic and health survey data was used for this study. From the result, materials used for roof, wall and floor were found to have a significant relation to fertility level of women in the last five years. Moreover, family size and births in the last five years were found to have a significant relationship. Significant variation in fertility level was observed among rural and urban residents of Ethiopia. To reduce the gap of fertility between rural and urban population, it is important to modernize different factors. These factors could be access to education, media, and providing employment opportunities in the modern economic sector. Besides this, it is important to develop and maintain the access of family planning services.

  13. Methods for a Retrospective Population-based and Clinic-based Subfertility Cohort Study: the Fertility Experiences Study.

    Science.gov (United States)

    Stanford, Joseph B; Sanders, Jessica N; Simonsen, Sara E; Hammoud, Ahmad; Gibson, Mark; Smith, Ken R

    2016-07-01

    Most cohort-based research for subfertility has been conducted in clinic-based cohorts, which may differ from population-based cohorts. We retrospectively recruited parallel cohorts of subfertile women: one by sampling two specialty fertility clinics in Utah, and one by population-based sampling based on marriage and birth records. The index date (of first clinic visit or subfertility status) was between 2000 and 2009, and we linked the women recruited to subsequent birth certificate records through December 2010. We enrolled 459 women through clinic-based sampling and 501 women through population-based sampling. Clinic-based women were older, had higher annual household income and more likely to have had a most intensive treatment of intrauterine insemination (31%) or in vitro fertilisation (46%) than women from population recruitment (19% and 14% respectively). Conversely, they were less likely to have received no medical treatment (9%) compared to women from population recruitment (41%). For both types of sampling, prior to eligibility screening, non-responders were less likely to link to a live birth than responders: 51% vs. 58% for clinic-based, and 69% vs. 76% for the population-based with an index date in 2004. Population-based sampling for subfertility cohort research identifies women who were more likely to have had less intensive treatment or no treatment. However, in both clinic-based and population-based sampling, women who have had a live birth are more likely to respond to retrospective recruitment. © 2016 John Wiley & Sons Ltd.

  14. Hispanic Assimilation and Fertility in New Destinations.

    Science.gov (United States)

    Lichter, Daniel T; Johnson, Kenneth M; Turner, Richard N; Churilla, Allison

    2012-01-01

    This paper evaluates comparative patterns of fertility in new Hispanic destinations and established gateways using pooled cross-sectional data from the 2005-2009 microdata files of the American Community Survey. Changing Hispanic fertility provides a useful indicator of cultural incorporation. Analyses show that high fertility among Hispanics has been driven in part by the Mexican-origin and other new immigrant populations (e.g., noncitizens, those with poor English language skills, etc.). However, high fertility rates among Hispanics - and Mexican-origin Hispanics in particular - cannot be explained entirely by socio-demographic characteristics that place them at higher risk of fertility. For 2005-2009, Hispanic fertility rates were 48 percent higher than fertility among whites; they were roughly 25 percent higher after accounting for differences in key social characteristics, such as age, nativity, county of origin, and education. Contrary to most previous findings of spatial assimilation among in-migrants, fertility rates among Hispanics in new destinations exceeded fertility in established gateways by 18 percent. In the multivariate analyses, Hispanics in new destinations were roughly 10 percent more likely to have had a child in the past year than those living in established gateways. Results are consistent with sub-cultural explanations of Hispanic fertility and raise new questions about the spatial patterning of assimilation and the formation of ethnic enclaves outside traditional settlement areas.

  15. Socio-economic status and fertility decline: Insights from historical transitions in Europe and North America.

    Science.gov (United States)

    Dribe, Martin; Breschi, Marco; Gagnon, Alain; Gauvreau, Danielle; Hanson, Heidi A; Maloney, Thomas N; Mazzoni, Stanislao; Molitoris, Joseph; Pozzi, Lucia; Smith, Ken R; Vézina, Hélène

    2017-03-01

    The timings of historical fertility transitions in different regions are well understood by demographers, but much less is known regarding their specific features and causes. In the study reported in this paper, we used longitudinal micro-level data for five local populations in Europe and North America to analyse the relationship between socio-economic status and fertility during the fertility transition. Using comparable analytical models and class schemes for each population, we examined the changing socio-economic differences in marital fertility and related these to common theories on fertility behaviour. Our results do not provide support for the hypothesis of universally high fertility among the upper classes in pre-transitional society, but do support the idea that the upper classes acted as forerunners by reducing their fertility before other groups. Farmers and unskilled workers were the latest to start limiting their fertility. Apart from these similarities, patterns of class differences in fertility varied significantly between populations.

  16. Maternal use of fertility drugs and risk of cancer in children--a nationwide population-based cohort study in Denmark

    DEFF Research Database (Denmark)

    Hargreave, Marie; Jensen, Allan; Nielsen, Thor Schütt Svane

    2015-01-01

    Large population-based studies are needed to examine the effect of maternal use of fertility drugs on the risk of cancer in children, while taking into account the effect of the underlying infertility. A cohort of 123,322 children born in Denmark between 1964 and 2006 to 68,255 women who had been...... evaluated for infertility was established. We used a case-cohort design and calculated hazard ratios (HRs) for cancer in childhood (0-19 years) and in young adulthood (20-29 years) associated with maternal use of six groups of fertility drugs (clomiphene, gonadotropins [i.e., human menopausal gonadotropins...... and follicle-stimulating hormone], gonadotropin-releasing hormone analogs, human chorionic gonadotropins, progesterone and other fertility drugs). We found no statistically significant association between maternal use of fertility drugs and risk for overall cancer in childhood or young adulthood. However...

  17. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

    Science.gov (United States)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

    2016-01-15

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings. Copyright © 2015. Published by Elsevier B.V.

  18. Fertility determinants in Puerto Rico.

    Science.gov (United States)

    Warren, C W

    1987-01-01

    This paper examines the proximate determinants of fertility in Puerto Rico using data from a 1982 island-wide study. Contraceptive use was found to be the primary direct determinant of fertility in Puerto Rico, both for the total population and for each level of education studied. Female sterilization is the most prevalent method of contraception used in Puerto Rico at each educational level. Marriage is also important in Puerto Rico and is the only proximate determinant that varies across education groups. Late age at first marriage, in addition to high contraceptive use, accounts for the below-replacement fertility of women who have more than a high school education. In contrast, women who have not completed high school tend to marry early and not practice contraception for birth-spacing purposes. This study shows the advantages of analyzing fertility determinants at the population subgroup level (i.e., women of various educational attainment levels) so that the fertility of the total population can be better understood.

  19. What has high fertility got to do with the low birth weight problem in Africa?

    Directory of Open Access Journals (Sweden)

    Ivy Kodzi

    2013-04-01

    Full Text Available BACKGROUND There has been much concern about adverse individual and societal consequences of high fertility in sub-Saharan Africa. One concern is that children of high birth orders may have low birth weight. However, the evidence for such an effect is not strong. OBJECTIVE Our objective is to investigate whether a woman's high parity status might increase her risks of having a baby with low birth weight. METHODS Pooling 60 Demographic and Health Surveys data-sets from 32 sub-Saharan countries, we selected children of mothers who had at least two births of order two or higher within the five years preceding the surveys. We modeled the probability of having a child with low birth weight and controlled for all mother-specific, household, or community characteristics that are constant over the period of analysis, by including fixed-effects for the mother. We also controlled for salient factors including sex, maternal age, preceding birth interval, and whether prenatal care was received. RESULTS We found no adverse effect of increasing parity on the odds of having a child with low birth weight at normative ranges; such effects only manifest at extremely high parities - nine or more children. At moderately high parities, the chance of low birth weight is actually lower than at very low parities. CONCLUSIONS While high fertility may lead to various adverse outcomes for African families, low birth weight appears not to be among these outcomes. Other factors, such as adolescent childbearing, poverty, and inadequate prenatal care may be more important determinants of low birth weight in Africa.

  20. Egg energetics, fertilization kinetics, and population structure in echinoids with facultatively feeding larvae.

    Science.gov (United States)

    Zigler, Kirk S; Lessios, H A; Raff, Rudolf A

    2008-10-01

    Larvae of marine invertebrates either arise from small eggs and feed during their development or arise from large eggs that proceed to metamorphosis sustained only from maternal provisioning. Only a few species are known to possess facultatively feeding larvae. Of about 250 echinoid species with known mode of development, only two, Brisaster latifrons and Clypeaster rosaceus, are known to develop through facultatively planktotrophic larvae. To obtain more information on this form of development and its consequences, we determined egg size and egg energetic and protein content of these two species. We found that eggs of B. latifrons resemble those of species with nonfeeding larvae in these characteristics more than those of C. rosaceus. We also compared DNA sequences of the cytochrome oxidase (COI) gene from the Caribbean C. rosaceus to those of the sympatric planktotrophic developer C. subdepressus and also to those of the eastern Pacific species C. europacificus to estimate the degree of divergence between species with different developmental modes. Comparison of COI sequences of C. rosaceus from Panama and Florida revealed that there is no geographic differentiation in this species. Cross-fertilization experiments between C. rosaceus and C. subdepressus indicated that bidirectional gametic incompatibility has evolved between the two species.

  1. Oligo-dT selected spermatozoal transcript profiles differ among higher and lower fertility dairy sires.

    Science.gov (United States)

    Card, C J; Krieger, K E; Kaproth, M; Sartini, B L

    2017-02-01

    Spermatozoal messenger RNA (mRNA) has the potential as a molecular marker for sire fertility because this population can reflect gene expression that occurred during spermatogenesis and may have a functional role in early embryonic development. The goal of this study was to compare the oligo-dT selected spermatozoal transcript profiles of higher fertility (Conception Rate (CR) 1.8-3.5) and lower fertility (CR -2.9 to -0.4) sires using Ribonucleic Acid Sequencing (RNA-Seq). A total of 3227 transcripts and 5366 transcripts were identified in the higher and lower fertility populations, respectively. While common transcripts between the two populations were identified (2422 transcripts), several transcripts were also unique to the fertility populations including 805 transcripts that were unique to the higher fertility population and 2944 transcripts that were unique to the lower fertility population. From gene ontological analysis, the transcripts unique to each fertility population differed in Biological Processes (BP), including enrichment of regulatory transcripts for growth and protein kinase activity in the higher fertility bulls. Biological variation in transcript presence among individual sires was also found. Of the candidate fertility spermatozoal transcripts chosen from the RNA-Seq population analysis reported here and previous publications, COX7C was negatively correlated with sire fertility. Using high-throughput sequencing, candidate spermatozoal transcripts were identified for further study as potential markers for sire fertility. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Modeling controlled nutrient release from a population of polymer coated fertilizers: statistically based model for diffusion release.

    Science.gov (United States)

    Shaviv, Avi; Raban, Smadar; Zaidel, Elina

    2003-05-15

    A statistically based model for describing the release from a population of polymer coated controlled release fertilizer (CRF) granules by the diffusion mechanism was constructed. The model is based on a mathematical-mechanistic description of the release from a single granule of a coated CRF accounting for its complex and nonlinear nature. The large variation within populations of coated CRFs poses the need for a statistically based approach to integrate over the release from the individual granules within a given population for which the distribution and range of granule radii and coating thickness are known. The model was constructed and verified using experimentally determined parameters and release curves of polymer-coated CRFs. A sensitivity analysis indicated the importance of water permeability in controlling the lag period and that of solute permeability in governing the rate of linear release and the total duration of the release. Increasing the mean values of normally distributed granule radii or coating thickness, increases the lag period and the period of linear release. The variation of radii and coating thickness, within realistic ranges, affects the release only when the standard deviation is very large or when water permeability is reduced without affecting solute permeability. The model provides an effective tool for designing and improving agronomic and environmental effectiveness of polymer-coated CRFs.

  3. Finding the Balance: Fertility Control for the Management of Fragmented Populations of a Threatened Rock-Wallaby Species

    Directory of Open Access Journals (Sweden)

    Nicole Willers

    2015-12-01

    Full Text Available Populations of Australian marsupials can become overabundant, resulting in detrimental impacts on the environment. For example, the threatened black-flanked rock-wallaby ( Petrogale lateralis lateralis has previously been perceived as overabundant and thus ‘unwanted’ when they graze crops and cause habitat degradation. Hormonally-induced fertility control has been increasingly used to manage population size in other marsupials where alternative management options are not viable. We tested whether deslorelin, a superagonist of gonadotropin-releasing hormone (GnRH, would suppress reproduction in free-living adult female rock-wallabies without adversely impacting body condition. We trapped, synchronised reproduction and allocated female rock-wallabies to a placebo implant (control, n = 22, one (n = 22 or two (n = 20 subcutaneous implants of deslorelin. Females were then recaptured over the following 36 months to monitor reproduction, including Luteinising Hormone levels, and body condition. Following treatment, diapaused blastocysts reactivated in five females and the resulting young were carried through to weaning. No wallabies treated with deslorelin, conceivede a new young for at least 27 months. We did not observe adverse effects on body condition on treated females. We conclude that deslorelin implants are effective for the medium-term suppression of reproduction in female black-flanked rock-wallabies and for managing overabundant populations of some marsupials.

  4. Carbon mineralization and soil fertility at high altitude grasslands in the Bolivian Andean

    Science.gov (United States)

    Zornoza, R.; Muñoz, M. A.; Faz, A.

    2012-04-01

    The high grasslands of Apolobamba provide a natural habitat for a high number of wild and domestic camelids such as vicuna (Vicugna vicugna) and alpaca (Lama pacos) in Bolivia. Because of the importance of the camelid raising for the Apolobambás inhabitant economy, it is fundamental to determine the natural resources condition and their availability for the camelid support. The soil organic matter plays a crucial role in the maintenance of the soil fertility at high grasslands. On the other hand, soil respiration is the primary pathway for CO2 fixed by plants returning to the atmosphere and its study is essential to evaluate the soil organic matter mineralization and the global C cycle. Based on this, the objectives of this research were to: (i) evaluate the soil fertility and (ii) determine soil organic matter mineralization on the basis of CO2 releases in Apolobamba. Regarding the lastly vicuna censuses carried out in the studied area, eight representative zones with dissimilar vicuna densities were selected. Other characteristics were also considered to select the study zones: (1) alpaca densities, (2) vegetation communities (3) plant cover and (4) landscape and geo-morphological description. Soil samples from different samplings were collected. Soil respiration was determined at two temperatures: 15 °C (based on the highest atmosphere temperature that was registered in the area) and 25 °C, in order to monitor the increase in soil respiration (Q10). The physico-chemical soil results pointed out the good soil fertility. However, erosive processes could be taken place likely caused by the alpaca grazing. High total organic carbon contents were observed corresponding to the highest soil respiration at 15 °C. This observation was supported by the relationship found between the total organic carbon and the soil respiration. A noticeable increase of the soil respiration when the temperature increased 10 °C was reported (from 1083 ± 47 g C m-2 yr-1 at 15 °C to

  5. Influence of Plant Population and Nitrogen-Fertilizer at Various Levels on Growth and Growth Efficiency of Maize

    Directory of Open Access Journals (Sweden)

    M. I. Tajul

    2013-01-01

    Full Text Available Field experiments were conducted to evaluate plant population and N-fertilizer effects on yield and yield components of maize (Zea mays L.. Three levels of plant populations (53000, 66000, and 800000 plants ha−1 corresponding to spacings of 75 × 25, 60 × 25, and 50 × 25 cm and 4 doses of N (100, 140, 180, and 220 kg ha−1 were the treatment variables. Results revealed that plant growth, light interception (LI, yield attributes, and grain yield varied significantly due to the variations in population density and N-rates. Crop growth rate (CGR was the highest with the population of 80,000 ha−1 receiving 220 kg N ha−1, while relative growth rate (RGR showed an opposite trend of CGR. Light absorption was maximum when most of densely populated plant received the highest amount of N (220 kg N ha−1. Response of soil-plant-analysis development (SPAD value as well as N-content to N-rates was found significant. Plant height was the maximum at the lowest plant density with the highest amount of N. Plants that received 180 kg N ha−1 with 80,000 plants ha−1 had larger foliage, greater SPAD value, and higher amount of grains cob−1 that contributed to the maximum yield (5.03 t ha−1 and the maximum harvest index (HI compared to the plants in other treatments.

  6. Stage-Specific Effects of Population Density on the Development and Fertility of Lygus hesperus Knight

    Science.gov (United States)

    The western tarnished plant bug Lygus hesperus Knight, a major pest of cotton and other key economic crops, was tested for its sensitivity to population density during nymph and adult stages. Nymphs reared to adulthood under increasing densities exhibited incremental delays in maturation, heightened...

  7. Public pensions and population ageing : An economic analysis of fertility, migration and social-security policy

    NARCIS (Netherlands)

    Leers, T.

    2001-01-01

    This thesis examines the relation between the changing demographic composition of the population and its economic, political and international consequences from an economic-theoretical point of view. The ample current interest in this subject needs little comment. In the OECD-countries, virtually no

  8. Male Investments in High Quality Sperm Improve Fertilization Success, but May Have Negative Impact on Offspring Fitness in Whitefish

    Science.gov (United States)

    Kekäläinen, Jukka; Soler, Carles; Veentaus, Sami; Huuskonen, Hannu

    2015-01-01

    Many ejaculate traits show remarkable variation in relation to male social status. Males in disfavoured (subordinate) mating positions often invest heavily on sperm motility but may have less available resources on traits (e.g., secondary sexual ornaments) that improve the probability of gaining matings. Although higher investments in sperm motility can increase the relative fertilization success of subordinate males, it is unclear whether status-dependent differences in sperm traits could have any consequences for offspring fitness. We tested this possibility in whitefish (Coregonus lavaretus L.) by experimentally fertilizing the eggs of 24 females with the sperm of either highly-ornamented (large breeding tubercles, dominant) or less-ornamented (small tubercles, subordinate) males (split-clutch breeding design). In comparison to highly-ornamented individuals, less-ornamented males had higher sperm motility, which fertilized the eggs more efficiently, but produced embryos with impaired hatching success. Also offspring size and body condition were lower among less-ornamented males. Furthermore, sperm motility was positively associated with the fertilization success and offspring size, but only in highly-ornamented males. Together our results indicate that male investments on highly motile (fertile) sperm is not necessarily advantageous during later offspring ontogeny and that male status-dependent differences in sperm phenotype may have important effects on offspring fitness in different life-history stages. PMID:26389594

  9. In Vitro Fertilization in Women With Inflammatory Bowel Disease Is as Successful as in Women From the General Infertility Population

    Science.gov (United States)

    Oza, Sveta Shah; Pabby, Vikas; Dodge, Laura E.; Moragianni, Vasiliki A.; Hacker, Michele R.; Fox, Janis H.; Correia, Katharine; Missmer, Stacey A.; Ibrahim, Yetunde; Penzias, Alan S.; Burakoff, Robert; Friedman, Sonia; Cheifetz, Adam S.

    2015-01-01

    BACKGROUND & AIMS Inflammatory bowel disease (IBD) affects women of reproductive age, so there are concerns about its effects on fertility. We investigated the success of in vitro fertilization (IVF) in patients with IBD compared with the general (non-IBD) IVF population. METHODS We conducted a matched retrospective cohort study of female patients with IBD who under-went IVF from 1998 through 2011 at 2 tertiary care centers. Patients were matched 4:1 to those without IBD (controls). The primary outcome was the cumulative rate of live births after up to 6 cycles of IVF. Secondary outcomes included the proportion of patients who became pregnant and the rate of live births for each cycle. RESULTS Forty-nine patients with Crohn’s disease (CD), 71 patients with ulcerative colitis (UC), 1 patient with IBD-unclassified, and 470 controls underwent IVF during the study period. The cumulative rate of live births was 53% for controls, 69% for patients with UC (P = .08 compared with controls), and 57% for patients with CD (P = .87 compared with controls). The incidence of pregnancy after the first cycle of IVF was similar among controls (40.9%), patients with UC (49.3%; P = .18), and patients with CD (42.9%; P = .79). Similarly, the incidence of live births after the first cycle of IVF was similar among controls (30.2%), patients with UC (33.8%; P = .54), and patients with CD (30.6%; P = .95). CONCLUSIONS Based on a matched cohort study, infertile women with IBD achieve rates of live births after IVF that are comparable with those of infertile women without IBD. PMID:25818081

  10. Humic Fertilizer and Vermicompost Applied to the Soil Can Positively Affect Population Growth Parameters of Trichogramma brassicae (Hymenoptera: Trichogrammatidae) on Eggs of Tuta absoluta (Lepidoptera: Gelechiidae).

    Science.gov (United States)

    Mohamadi, P; Razmjou, J; Naseri, B; Hassanpour, M

    2017-12-01

    The tomato leaf miner, Tuta absoluta (Meyrick), is a devastating pest of tomato worldwide. One of the control measures of T. absoluta is the use of biological control agents, such as Trichogramma wasps. Interactions between natural enemies and insect pests may be affected by application of fertilizers, because changes in plant quality through the fertilizer application may therefore affect herbivore characteristics and suitability of them to parasitism. Laboratory tests were carried out to evaluate the life table parameters of Trichogramma brassicae Bezdenko on T. absoluta eggs reared on tomato plants treated either with vermicompost (40%), humic fertilizer (2 g/kg soil), or control (suitable mixture of field soil and sand). Population growth parameters of T. brassicae were affected by fertilizer treatments. Significant differences were found for immature life period and total fecundity of T. brassicae on the treatments. Differences of intrinsic rate of natural increase (r m ), finite rate of increase (λ), net reproductive rate (R 0 ), mean generation time (T), and doubling time (DT) of T. brassicae among treatments were also significant. The lowest values of r m , λ, and R 0 were recorded for T. brassicae developed on T. absoluta eggs on control treatment, whereas the highest values of these parameters were observed on 2 g/kg humic fertilizer. Furthermore, T. brassicae had the shortest T and DT values on 2 g/kg humic fertilizer and 40% vermicompost treatments. Our results showed that application of humic fertilizer and vermicompost could positively affect population growth parameters of T. brassicae on eggs of T. absoluta fed on tomato plants.

  11. The Influence of Mineral Fertilizer Combined With a Nitrification Inhibitor on Microbial Populations and Activities in Calcareous Uzbekistanian Soil Under Cotton Cultivation

    Directory of Open Access Journals (Sweden)

    Dilfuza Egamberdiyeva

    2001-01-01

    Full Text Available Application of fertilizers combined with nitrification inhibitors affects soil microbial biomass and activity. The objective of this research was to determine the effects of fertilizer application combined with the nitrification inhibitor potassium oxalate (PO on soil microbial population and activities in nitrogen-poor soil under cotton cultivation in Uzbekistan. Fertilizer treatments were N as urea, P as ammophos, and K as potassium chloride. The nitrification inhibitor PO was added to urea and ammophos at the rate of 2%. Three treatments—N200P140K60 (T1, N200 P140 POK60 (T2, and N200 P140 POK60 (T3 mg kg-1 soil—were applied for this study. The control (C was without fertilizer and PO. The populations of oligotrophic bacteria, ammonifying bacteria, nitrifying bacteria, denitrifying bacteria, mineral assimilating bacteria, oligonitrophilic bacteria, and bacteria group Azotobacter were determined by the most probable number method. The treatments T2 and T3 increased the number of oligonitrophilic bacteria and utilization mineral forms of nitrogen on the background of reducing number of ammonifying bacteria. T2 and T3 also decreased the number of nitrifying bacteria, denitrifying bacteria, and net nitrification. In conclusion, our experiments showed that PO combined with mineral fertilizer is one of the most promising compounds for inhibiting nitrification rate, which was reflected in the increased availability and efficiency of fertilizer nitrogen to the cotton plants. PO combined with mineral fertilizer has no negative effects on nitrogen-fixing bacteria Azotobacter and oligo-nitrophilic bacteria.

  12. Herbivory prevents positive responses of lowland plants to warmer and more fertile conditions at high altitudes

    National Research Council Canada - National Science Library

    Kaarlejärvi, Elina; Eskelinen, Anu; Olofsson, Johan; McArthur, Clare

    2013-01-01

    ... ) were transplanted to an open tundra site with native mountain tundra vegetation, and the effects of full factorial combinations of herbivore exclosures, warming and fertilization on transplant...

  13. Rapid production of organic fertilizer by dynamic high-temperature aerobic fermentation (DHAF) of food waste.

    Science.gov (United States)

    Jiang, Yang; Ju, Meiting; Li, Weizun; Ren, Qingbin; Liu, Le; Chen, Yu; Yang, Qian; Hou, Qidong; Liu, Yiliang

    2015-12-01

    Keep composting matrix in continuous collision and friction under a relatively high-temperature can significantly accelerate the progress of composting. A bioreactor was designed according to the novel process. Using this technology, organic fertilizer could be produced within 96h. The electric conductivity (EC) and pH value reached to a stable value of 2.35mS/cm and 7.7 after 96h of fermentation. The total carbon/total nitrogen (TC/TN) and dissolved carbon/dissolved nitrogen (DC/DN) ratio was decrease from 27.3 and 36.2 to 17.4 and 7.6 respectively. In contrast, it needed 24days to achieve the similar result in traditional static composting (TSC). Compost particles with different size were analyzed to explore the rapid degradation mechanism of food waste. The evidence of anaerobic fermentation was firstly discovered in aerobic composting. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. High Speed Stereovision Setup for Position and Motion Estimation of Fertilizer Particles Leaving a Centrifugal Spreader

    Directory of Open Access Journals (Sweden)

    Bilal Hijazi

    2014-11-01

    Full Text Available A 3D imaging technique using a high speed binocular stereovision system was developed in combination with corresponding image processing algorithms for accurate determination of the parameters of particles leaving the spinning disks of centrifugal fertilizer spreaders. Validation of the stereo-matching algorithm using a virtual 3D stereovision simulator indicated an error of less than 2 pixels for 90% of the particles. The setup was validated using the cylindrical spread pattern of an experimental spreader. A 2D correlation coefficient of 90% and a Relative Error of 27% was found between the experimental results and the (simulated spread pattern obtained with the developed setup. In combination with a ballistic flight model, the developed image acquisition and processing algorithms can enable fast determination and evaluation of the spread pattern which can be used as a tool for spreader design and precise machine calibration.

  15. Barriers to cross-fertilization between populations of a widely dispersed polychaete species are unlikely to have arisen through gametic compatibility arms-races.

    Science.gov (United States)

    Styan, Craig A; Kupriyanova, Elena; Havenhand, Jon N

    2008-12-01

    Although there are theoretical reasons to suspect that gametic incompatibility may develop readily among populations of broadcast spawning marine invertebrates, there have been very few studies documenting geographic patterns of interpopulation incompatibility for any species. To address this we determined how successfully individuals of the intertidal serpulid polychaete, Galeolaria caespitosa, can cross-fertilize within and among populations from across temperate Australia. Fertilization assays revealed asymmetrical differences between very distantly located populations from different coasts, with near-complete incompatibility between eggs from Sydney with sperm from Adelaide, but the reverse cross (Adelaide eggs, Sydney sperm) was reasonably compatible. Although that pattern was congruent with a clear difference in Cytochrome B sequences between worms on the south and east coasts of Australia, we also detected some indication of interpopulation incompatibility within the genetic grouping on east coast, between two populations separated by only 220 km. We then assessed whether commonly proposed gametic compatibility arms-races could account for these patterns. Our results suggest reduced gametic compatibility may reduce a female's maximum fertilization potential, resulting in a cost to this potential mechanism for reducing polyspermy. Consequently, the apparently rapid development of reproductive barriers here seems unlikely to have been driven by arms-races involving sexual conflict over fertilization rate.

  16. Reestablishing a spawning population of lake trout in Lake Superior with fertilized eggs in artificial turf incubators

    Science.gov (United States)

    Bronte, Charles R.; Schram, Stephen T.; Selgeby, James H.; Swanson, Bruce L.

    2002-01-01

    Fertilized eggs from lake trout Salvelinus namaycush were placed in artificial turf incubators and deployed on Devils Island Shoal, Lake Superior, in an attempt to reestablish a spawning population on this once important spawning area. Efficacy was measured by the changes in catch rates, age composition, and origin of adult lake trout returning to the shoal in the fall in subsequent years. The abundance of lake trout spawners without fin clips, which implies that these fish hatched in the lake, increased throughout the sampling period, whereas the abundance of hatchery-reared fish (indicated by one or more fin clips) stocked for restoration purposes remained low. Year-class-specific stock-recruitment analysis suggested that the recruitment of unclipped spawners was related to the number of eggs planted in previous years rather than to spawning by the few adult lake trout visiting the reef. Increases in adult fish at Devils Island Shoal were independent of trends at adjacent sites, where unclipped spawner abundances remained low. Enhanced survival to hatch and apparent site imprinting of young lake trout make this technique a viable alternative to stocking fingerling and yearling lake trout to reestablish spawning populations on specific sites in the Great Lakes.

  17. No evidence for increased extinction proneness with decreasing effective population size in a parasitoid with complementary sex determination and fertile diploid males

    Directory of Open Access Journals (Sweden)

    Mazzi Dominique

    2010-11-01

    Full Text Available Abstract Background In species with single locus complementary sex determination (sl-CSD, the sex of individuals depends on their genotype at one single locus with multiple alleles. Haploid individuals are always males. Diploid individuals are females when heterozygous, but males when homozygous at the sex-determining locus. Diploid males are typically unviable or effectively sterile, hence imposing a genetic load on populations. Diploid males are produced from matings of partners that share an allele at the sex-determining locus. The lower the allelic diversity at the sex-determining locus, the more diploid males are produced, ultimately impairing the growth of populations and jeopardizing their persistence. The gregarious endoparasitoid wasp Cotesia glomerata is one of only two known species with sl-CSD and fertile diploid males. Results By manipulating the relatedness of the founders, we established replicated experimental populations of the parasitoid C. glomerata differing in their genetic effective size, and thus in allelic richness at the sex-determining locus and in the expected magnitude of diploid male production. Our long-term survey of population welfare and persistence did not provide evidence for increased proneness to population extinction with decreasing initial genetic effective population size. Most recorded surrogates of fitness nevertheless decayed over time and most experimental populations eventually went extinct, suggesting that the negative effects of inbreeding outweighed any premium from the fertility of diploid males. Conclusions The fertility of diploid males may have evolved as an adaptation prompted by the risk of extinction looming over small isolated populations of species with sl-CSD. However, fertility of diploid males does not negate the costs imposed by their production, and although it may temporarily stave off extinction, it is not sufficient to eradicate the negative effects of inbreeding.

  18. Genetics and genomics to improve fertility in high producing dairy cows

    NARCIS (Netherlands)

    Veerkamp, R.F.; Beerda, B.

    2007-01-01

    Improving dairy cow fertility by means of genetic selection is likely to become increasingly important, since it is now well established that declining fertility cannot only be arrested by improved management. Profit margins per kg milk produced are decreasing, therefore farmers need to reduce cost

  19. Excess Fertility and Family Planning in Rwanda : Understanding the shift to a high contraceptive prevalence country

    NARCIS (Netherlands)

    Muhoza Ndaruhuye, Dieudonne

    2014-01-01

    Rwanda has experienced an impressive increase in contraceptive use and fertility decline during the last decade. Between 2005 and 2010, the contraceptive prevalence rate (CPR) has risen from 17 % to 52%, reducing unmet need and the total fertility substantially (from 6.1 to 4.6 children per women).

  20. Cultural factors affecting the demographic structure of a high altitude Nepalese population.

    Science.gov (United States)

    Weitz, C A; Pawson, I G; Weitz, M V; Lang, S D; Lang, A

    1978-01-01

    Surveys were undertaken to study the fertility of Sherpa and Tibetan women living at altitudes over 3400 meters in Nepal. 2 teams independently collected demographic data during 1970 and 1971. Of all women who reported their ages to be 15 years and older, 348 (37.0%) provided menarchial data, 294 (31.2%) related the age at which they first became pregnant, and 420 (44.6%) replied to questions on the number of live births, neonatal deaths, infant deaths, child deaths, and the number of living children. The average completed fertility (4.77 live births) and estimated crude birthrate (31-33/1000) are low relative to low altitude peasant populations as well as to high altitude Andean peasants. Environmental phenomena (hypoxia, iodine deficiency) may be associated with retarded menarchial age and high infant mortality, but the major factors causing the low fertility seem to be cultural rather than environmental. Traditional ceremonial requirements delay the age at marriage until the mid or late twenties. Male and female celibacy is promoted by religious practices. Migrant females and women married to migrant males report reduced fertility. This is possibly due to poor nutrition and health care. Nonmigrant women living in villages participating extensively in the cash economy have greater access to the growing market economy, health care, and education and report higher numbers of live births and fewer child deaths.

  1. Quantitative Trait Loci Associated with Pollen Fertility under High Temperature Stress at Flowering Stage in Rice (Oryza sativa

    Directory of Open Access Journals (Sweden)

    Ying-hui XIAO

    2011-09-01

    Full Text Available High temperature stress (HTS, an increasingly important problem in rice production, significantly reduces rice yield by reducing pollen fertility and seed setting rate. Breeding rice varieties with tolerance to HTS at the flowering stage is therefore essential for maintaining rice production as the climate continues to become warm. In this study, two quantitative trait loci (QTLs underlying tolerance to HTS were identified using recombinant inbred lines derived from a cross between an HTS-tolerant rice cultivar 996 and a sensitive cultivar 4628. Pollen fertility was used as a heat-tolerance indicator for the lines subjected to HTS at the flowering stage in field experiments. Two QTLs that affected pollen fertility, qPF4 and qPF6, were detected between RM5687 and RM471 on chromosome 4, and between RM190 and RM225 on chromosome 6, by using the composite interval mapping (CIM analysis. The two QTLs explained 15.1% and 9.31% of the total phenotypic variation in pollen fertility, and increased the pollen fertility of the plants subjected to HTS by 7.15% and 5.25%, respectively. The positive additive effects of the two QTLs were derived from the 996 alleles. The two major QTLs identified would be useful for further fine mapping and cloning of these genes and for molecular marker-assistant breeding of heat-tolerant rice varieties.

  2. High Nitrogen Fertilization of Tobacco Crop in Headwater Watershed Contaminates Subsurface and Well Waters with Nitrate

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    D. R. Kaiser

    2015-01-01

    Full Text Available Our hypothesis was that subsurface and well waters in watershed with shallow, stony soils, steep landscapes, and cropped to tobacco are contaminated by nitrate. Nitrate in soil solution was monitored in (0.20 m and below (0.5 m root zone with tension lysimeters, in five transects. Water from two wells (beneath tobacco field and in native forest used for human consumption was also analyzed for nitrate. Soil bulk density, porosity, and saturated hydraulic conductivity were evaluated. Soil physical and hydrological properties showed great variation at different landscape positions and soil depths. Soil coarse grain size, high porosity, and saturated hydraulic conductivity favored leaching nitrate. Nitrate in soil solution from tobacco fields was greater than in natural environment. Nitrate reached depths bellow rooting zone with values as high as 80 mg L−1 in tobacco plantation. Water well located below tobacco plantation had high nitrate concentration, sometimes above the critical limit of 10 mg L−1. Tobacco cropping causes significant water pollution by nitrate, posing risk to human health. A large amount of nitrogen fertilizers applied to tobacco and nitrate in subsurface waters demonstrate the unsustainability of tobacco production in small farming units on steeps slopes, with stony and shallow soils.

  3. A 660-Kb deletion with antagonistic effects on fertility and milk production segregates at high frequency in Nordic Red cattle

    DEFF Research Database (Denmark)

    Kadri, Naveen Kumar; Sahana, Goutam; Charlier, Carole

    2014-01-01

    to the negative energy balance of high-producing cows at the peak of lactation. We herein describe the fine-mapping of a major fertility QTL in Nordic Red cattle, and identify a 660-kb deletion encompassing four genes as the causative variant. We show that the deletion is a recessive embryonically lethal mutation....... This probably results from the loss of RNASEH2B, which is known to cause embryonic death in mice. Despite its dramatic effect on fertility, 13%, 23% and 32% of the animals carry the deletion in Danish, Swedish and Finnish Red Cattle, respectively. To explain this, we searched for favorable effects on other...... traits and found that the deletion has strong positive effects on milk yield. This study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle, and that associated positive effects on milk yield may account for part...

  4. Efficacy of Vermicompost against fertilizers on Cicer and Pisum and on population diversity of N2 fixing bacteria.

    Science.gov (United States)

    Sinha, Jayanta; Biswas, Chanchal Kumar; Ghosh, Arup; Saha, Amit

    2010-05-01

    Vermicompost is a very important biofertilizer produced through the artificial cultivation of worms i.e. Vermiculture. Vermicompost is enriched with all beneficial soil bacteria and also contain many of the essential plant nutrients like N, P, K and micronutrients. It increases soil aeration, texture and jilt. In this work, study is being carried out to find out the effect of different fertilizers such as DAF, FYM and Vermicompost on various morphological parameters and on the in vitro growth of bacterial colonies and its diversity in relation to two important leguminous plants such as Pisum sp. and Cicer sp. Results showed that plant grown in Vermicompost pretreated soil exhibited maximum increase in all morphological parameters such as root length, shoot length, number of root branches, number of stem branches, number of leaves, number of flowers, number of pods and number of root nodules in four months sampling in comparison to untreated, FYM treated and DAP treated soils. Further in Vermicompost pretreated soil, number of N2 fixing bacterial colony was maximum and showed highest diversity indices (1.6 and 0.99 and 2.0 and 0.99 for Cicer sp. and Pisum sp. respectively) than FYM, DAP and untreated control. Thus not only does the Vermicompost stimulate plant growth but also it increases the N2 fixing bacterial population in soil and also its diversity.

  5. In vitro fertilization (IVF) using semi-defined culture conditions from low or high antral follicle count pubertal beef heifers

    Science.gov (United States)

    To compare the in vitro fertilization (IVF) and production (IVP) of embryos from low and high antral follicle count (AFC) heifers, AFC were determined on 106 heifers using transrectal ultrasonography. Ten heifers with the lowest AFC (avg. 13.2) and 10 heifers with the highest AFC (avg. 27.4) with ev...

  6. In vitro fertilization (IVF) from low or high antral follicle count pubertal beef heifers using semi-defined culture conditions

    Science.gov (United States)

    Antral follicle counts (AFC) vary among pubertal beef heifers. Our objective was to compare the in vitro maturation and fertilization of oocytes collected from low and high AFC heifers. Previously we reported results using serum-based IVF media and in this study report results using semi-defined m...

  7. [Fertility and HIV: equal opportunity for everyone].

    Science.gov (United States)

    Kedem, Eynat; Shahar, Eduardo; Hassoun, Gammal; Pollack, Shimon

    2013-04-01

    Highly active antiretroviral treatment (HAART), the increase in life expectancy and improved HIV viral detection methods, have all led to a change in attitude towards fertility in people living with HIV. There is now acknowledgment of the fundamental rights of HIV patients to parenthood and growing implementation of assisted fertility in this group. The aims of fertility treatment are prevention of infection in HIV-discordant couples, and treatment for fertility problems, identical to the general population. We review the influence of HIV on the reproduction systems of males and females, conditions requiring fertility intervention, various methods that are possible and describe the optional treatment existing in Israel for patients with viral infection, and specifically HIV.

  8. Population-based resequencing reveals that the flowering time adaptation of cultivated barley originated east of the Fertile Crescent.

    Science.gov (United States)

    Jones, Huw; Leigh, Fiona J; Mackay, Ian; Bower, Mim A; Smith, Lydia M J; Charles, Michael P; Jones, Glynis; Jones, Martin K; Brown, Terence A; Powell, Wayne

    2008-10-01

    Gene resequencing and association analysis present new opportunities to study the evolution of adaptive traits in crop plants. Here we apply these tools to an extensive set of barley accessions to identify a component of the molecular basis of the flowering time adaptation, a trait critical to plant survival. Using an association-based study to relate variation in flowering time to sequence-based polymorphisms in the Ppd-H1 gene, we identify a causative polymorphism (SNP48) that accounts for the observed variation in barley flowering time. This polymorphism also shows latitude-dependent geographical distribution, consistent with the expected clinal variation in phenotype with the nonresponsive form predominating in the north. Networks, genealogies, and phylogenetic trees drawn for the Ppd-H1 haplotypes reveal population structure both in wild barley and in domesticated barley landraces. The spatial distribution of these population groups indicates that phylogeographical analysis of European landraces can provide information relevant to the Neolithic spread of barley cultivation and also has implications for the origins of domesticated barley, including those with the nonresponsive ppd-H1 phenotype. Haplotypes containing the nonresponsive version of SNP48 are present in wild barley accessions, indicating that the nonresponsive phenotype of European landraces originated in wild barley. The wild accessions whose nonresponsive haplotypes are most closely similar to those of landraces are found in Iran, within a region suggested as an area for domestication of barley east of the Fertile Crescent but which has previously been thought to have contributed relatively little to the diversity of European cultivars.

  9. Persistent high fertility in Uganda: young people recount obstacles and enabling factors to use of contraceptives

    Directory of Open Access Journals (Sweden)

    Nalwadda Gorrette

    2010-09-01

    Full Text Available Abstract Background High fertility among young people aged 15-24 years is a public health concern in Uganda. Unwanted pregnancy, unsafe induced abortions and associated high morbidity and mortality among young women may be attributed to low contraceptive use. This study aims at exploring reasons for low contraceptive use among young people. Methods In 16 focus group discussions, the views of young people about obstacles and enabling factors to contraceptive use in Mityana and Mubende districts, Uganda were explored. The groups were homogeneously composed by married and unmarried men and women, between the ages of 15-24. The data obtained was analyzed using qualitative content analysis. Results Young men and women described multiple obstacles to contraceptive use. The obstacles were categorized as misconceptions and fears related to contraception, gender power relations, socio-cultural expectations and contradictions, short term planning, and health service barriers. Additionally, young people recounted several enabling factors that included female strategies to overcome obstacles, changing perceptions to contraceptive use, and changing attitude towards a small family size. Conclusions Our findings suggest changing perceptions and behavior shift towards contraceptive use and a small family size although obstacles still exist. Personalized strategies to young women and men are needed to motivate and assist young people plan their future families, adopt and sustain use of contraceptives. Reducing obstacles and reinforcing enabling factors through education, culturally sensitive behavior change strategies have the potential to enhance contraceptives use. Alternative models of contraceptive service delivery to young people are proposed.

  10. Yield gains of coffee plants from phosphorus fertilization may not be generalized for high density planting

    Directory of Open Access Journals (Sweden)

    Samuel Vasconcelos Valadares

    2014-06-01

    Full Text Available Inconclusive responses of the adult coffee plant to phosphorus fertilization have been reported in the literature, especially when dealing with application of this nutrient in high density planting systems. Thus, this study was carried out for the purpose of assessing the response of adult coffee plants at high planting density in full production (in regard to yield and their biennial cycle/stability to the addition of different sources and application rates of P in the Zona da Mata region of Minas Gerais, Brazil. The experiment with coffee plants of the Catucaí Amarelo 6/30 variety was carried out over four growing seasons. Treatments were arranged in a full factorial design [(4 × 3 + 1] consisting of four P sources (monoammonium phosphate, simple superphosphate, natural reactive rock phosphate from Algeria (Djebel-Onk, and FH 550®, three P rates (100, 200, and 400 kg ha-1 year-1 of P2O5, and an additional treatment without application of the nutrient (0 kg ha-¹ year-¹. A randomized block experimental design was used with three replicates. The four seasons were evaluated as subplots in a split plot experiment. The P contents in soil and leaves increased with increased rates of P application. However, there was no effect from P application on the yield and its biennial cycle/stability regardless of the source used over the four seasons assessed.

  11. Female infertility in India: Causes, treatment and impairment of fertility in selected districts with high prevalence

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    Shraboni Patra

    2017-01-01

    Full Text Available Although the ‘universal access to sexual and reproductive health care’ has received priority in the SDG‐3, the rural women experiencing infertility problem in India are unable to access and afford quality reproductive health care. The study investigates the present infertility situation, with a focus on risk factors, treatment seeking for infertility, and impact of infertility on fertility in India and its districts with high infertility prevalence. The DLHS‐3 data is used. Top fifteen districts with high infertility prevalence are selected for analysis. Simple bivariate and multivariate techniques are applied. In India, the prevalence of ever‐experienced primary, secondary, and current infertility is 6.6%, 2.1% and 4.6% respectively, whereas, in the selected districts, the estimates for the same indicators are 15%, 3.1%, and 5% respectively. A higher prevalence of reported symptoms of RTIs/STIs and menstrual problems is observed among women who ever had infertility. Treatment seeking for infertility is low in Korba and Koryia. The MCEB is less among women who ever had experienced infertility. The prevalence of ever‐experienced infertility and current infertility is considerably higher among women from socio‐economically disadvantaged sections. Awareness of RTIs, STIs, and menstrual problems, and preventive care can reduce infertility among rural women.

  12. Fertilization 2: Polyspermic Fertilization.

    Science.gov (United States)

    Mizushima, Shusei

    2017-01-01

    During fertilization in animals, a haploid egg nucleus fuses with a haploid sperm nucleus to restore the diploid genome. In most animals including mammals, echinoderms, and teleostei, the penetration of only one sperm into an egg is ensured at fertilization because the entry of two or more sperm is prevented by polyspermy block systems in these eggs. On the other hand, several animals such as birds, reptiles, and most urodele amphibians exhibit physiological polyspermy, in which the entry of several sperm into one egg is permitted. However, in these polyspermic eggs, only one sperm nucleus is involved in zygotic formation with a female nucleus, thereby avoiding syngamy with multiple sperm nuclei. In the chicken, 20-60 sperm are generally found within the egg cytoplasm at fertilization and this number is markedly higher than that of other polyspermic species; however, avian-specific events such as the degeneration and mitosis of supernumerary sperm nuclei during early embryo development allow a polyspermic egg to develop normally. This chapter describes current knowledge on polyspermy-related events in avian eggs during fertilization, and is characterized by a comparison to the fertilization modes of other vertebrates. The close relationship between sperm numbers and egg sizes, and the movement of supernumerary sperm nuclei towards the periphery of the egg cytoplasm and their degeneration are summarized. The molecular mechanisms by which polyspermy initiates egg activation to start embryo development are also discussed.

  13. High doses of ethylene diurea (EDU) are not toxic to willow and act as nitrogen fertilizer.

    Science.gov (United States)

    Agathokleous, Evgenios; Paoletti, Elena; Saitanis, Costas J; Manning, William J; Shi, Cong; Koike, Takayoshi

    2016-10-01

    Ethylene diurea (EDU) is synthetic chemical which protects plants against damage caused by ground level O3 and is used experimentally as a biomonitoring tool at doses usually ranging from 200 to 400mgL(-1) a.i. Although several studies have investigated the protective action of EDU, this mechanism remains unclear. Important uncertainties in EDU action are whether EDU acts as a source of nitrogen (N) to plants and whether high doses are phytotoxic. In order to answer these questions, we conducted an open-field experiment where potted willow (Salix sachalinensis Fr. Schm) plants were exposed to ambient O3 conditions and treated with 0, 800 or 1600mgL(-1) EDU as a soil drench, every nine days, for about 2.5months. We examined approximately 50 response variables. Based on N content in different plant organs, we found that (a) all EDU was transferred to the leaves and (b) high doses of EDU increased the leaf N content. However, EDU did not affect the C content and distribution within the plant body. Still, even at the highest dose, EDU was not toxic to this fast-growing species (however such a high dose should not be applied in uncontrolled environments); and there was no EDU persistence in the soil, as indicated by soil N content. Notably, our soil was free from organic matter and N-poor. EDU per se does not cause toxicity to willow plants when applied as drench to a soil with no organic matter, rather, high EDU doses may act as nitrogen fertilizer in a nitrogen-poor soil. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Socioeconomic status and fertility decline: Insights from historical transitions in Europe and North America

    Science.gov (United States)

    Dribe, Martin; Breschi, Marco; Gagnon, Alain; Gauvreau, Danielle; Hanson, Heidi A.; Maloney, Thomas N.; Mazzoni, Stanislao; Molitoris, Joseph; Pozzi, Lucia; Smith, Ken R.; Vézina, Hélène

    2016-01-01

    We have good knowledge of the timing of the historical fertility transitions in different regions, but we know much less regarding specific features and causes. In this study, we used longitudinal micro-level data for five local populations in Europe and North America to study the relationship between socioeconomic status and fertility during the transition. Using the same analytical model and identical class scheme, we examined the development of socioeconomic differences in marital fertility and related it to common theories on fertility behaviour. Our results do not provide support for the hypothesis of universally high fertility among the upper classes in pre-transitional society but support the idea that they acted as forerunners in the transition by reducing their fertility before other groups. Farmers and unskilled workers were latest to start to limit their fertility. Apart from this regularity, the patterns of class differences in fertility varied significantly among populations. PMID:27884093

  15. Methodology for establishing a population-based birth cohort focusing on couple fertility and children's development, the Upstate KIDS Study.

    Science.gov (United States)

    Buck Louis, Germaine M; Hediger, Mary L; Bell, Erin M; Kus, Christopher A; Sundaram, Rajeshwari; McLain, Alexander C; Yeung, Edwina; Hills, Elaine A; Thoma, Marie E; Druschel, Charlotte M

    2014-05-01

    Critical data gaps remain regarding infertility treatment and child development. We assessed the utility of a birth certificate registry for developing a population cohort aimed at answering such questions. We utilised the Upstate New York livebirth registry (n = 201,063) to select births conceived with (n = 4024) infertility treatment or exposed infants, who were then frequency-matched by residence to a random sample of infants conceived without (n = 14,455) treatment or unexposed infants, 2008-10. Mothers were recruited at 2-4 months postpartum and queried about their reproductive histories, including infertility treatment for comparison with birth certificate data. Overall, 1297 (32%) mothers of exposed and 3692 of unexposed (26%) infants enrolled. Twins represented 22% of each infant group. The percentage of infants conceived with/without infertility treatment was similar whether derived from the birth registry or maternal report: 71% none, 16% drugs or intrauterine insemination, and 14% assisted reproductive technologies (ART). Concordant reporting between the two data sources was 93% for no treatment, 88% for ART, and 83% for fertility drugs, but differed by plurality. Exposed infants had slightly (P certificates but not maternal report (38.7 ± 2.7 and 38.7 ± 2.9, respectively). Conversely, mean birthweight was comparable using birth certificates (3157 ± 704 and 3194 ± 679 g, respectively), but differed using maternal report (3167 ± 692 and 3224 ± 661, respectively P certificate registry is a suitable sampling framework as measured by concordance with maternally reported infertility treatment. Future efforts should address the impact of factors associated with discordant reporting on research findings. © 2014 John Wiley & Sons Ltd.

  16. Cohort Fertility Patterns in the Nordic Countries

    Directory of Open Access Journals (Sweden)

    Gunnar Andersson

    2009-04-01

    Full Text Available Previous analyses of period fertility suggest that the trends of the Nordic countries are sufficiently similar to speak of a common "Nordic fertility regime". We investigate whether this assumption can be corroborated by comparing cohort fertility patterns in the Nordic countries. We study cumulated and completed fertility of Nordic birth cohorts based on the childbearing histories of women born in 1935 and later derived from the population registers of Denmark, Finland, Norway, and Sweden. We further explore childbearing behaviour by women's educational attainment. The results show remarkable similarities in postponement and recuperation between the countries and very small differences in completed fertility across educational groups. Median childbearing age is about 2-3 years higher in the 1960-64 cohort than in the 1950-54 cohort, but the younger cohort recuperates the fertility level of the older cohort at ages 30 and above. A similar pattern of recuperation can be observed for highly educated women as compared to women with less education. An interesting finding is that of a positive relationship between educational level and the final number of children when women who become mothers at similar ages are compared. Country differences in fertility outcome are generally rather low. Childlessness is highest in Finland and lowest in Norway, and the educational differentials are largest in Norway. Despite such differences, the cohort analyses in many ways support the notion of a common Nordic fertility regime.

  17. Fertility preservation in young patients with cancer

    Directory of Open Access Journals (Sweden)

    Virender Suhag

    2015-01-01

    Full Text Available Infertility can arise as a consequence of treatment of oncological conditions. The parallel and continued improvement in both the management of oncology and fertility cases in recent times has brought to the forefront the potential for fertility preservation in patients being treated for cancer. Many survivors will maintain their reproductive potential after the successful completion of treatment for cancer. However total body irradiation, radiation to the gonads, and certain high dose chemotherapy regimens can place women at risk for acute ovarian failure or premature menopause and men at risk for temporary or permanent azoospermia. Providing information about risk of infertility and possible interventions to maintain reproductive potential are critical for the adolescent and young adult population at the time of diagnosis. There are established means of preserving fertility before cancer treatment; specifically, sperm cryopreservation for men and in vitro fertilization and embryo cryopreservation for women. Several innovative techniques are being actively investigated, including oocyte and ovarian follicle cryopreservation, ovarian tissue transplantation, and in vitro follicle maturation, which may expand the number of fertility preservation choices for young cancer patients. Fertility preservation may also require some modification of cancer therapy; thus, patients' wishes regarding future fertility and available fertility preservation alternatives should be discussed before initiation of therapy.

  18. Dark-matter halo mergers as a fertile environment for low-mass Population III star formation

    DEFF Research Database (Denmark)

    Bovino, S.; Latif, M. A.; Grassi, Tommaso

    2014-01-01

    While Population III (Pop III) stars are typically thought to be massive, pathways towards lower mass Pop III stars may exist when the cooling of the gas is particularly enhanced. A possible route is enhanced HD cooling during the merging of dark-matter haloes. The mergers can lead to a high...

  19. From Fertilization to Birth: Representing Development in High School Biology Textbooks

    Science.gov (United States)

    Wellner, Karen L.

    Biology textbooks are everybody's business. In accepting the view that texts are created with specific social goals in mind, I examined 127 twentieth-century high school biology textbooks for representations of animal development. Paragraphs and visual representations were coded and placed in one of four scientific literacy categories: descriptive, investigative, nature of science, and human embryos, technology, and society (HETS). I then interpreted how embryos and fetuses have been socially constructed for students. I also examined the use of Haeckel's embryo drawings to support recapitulation and evolutionary theory. Textbooks revealed that publication of Haeckel's drawings was influenced by evolutionists and anti-evolutionists in the 1930s, 1960s, and the 1990s. Haeckel's embryos continue to persist in textbooks because they "safely" illustrate similarities between embryos and are rarely discussed in enough detail to understand comparative embryology's role in the support of evolution. Certain events coincided with changes in how embryos were presented: (a) the growth of the American Medical Association (AMA) and an increase in birth rates (1950s); (b) the Biological Sciences Curriculum Study (BSCS) and public acceptance of birth control methods (1960s); (c) Roe vs. Wade (1973); (d) in vitro fertilization and Lennart Nilsson's photographs (1970s); (e) prenatal technology and fetocentrism (1980s); and (f) genetic engineering and Science-Technology-Society (STS) curriculum (1980s and 1990s). By the end of the twentieth century, changing conceptions, research practices, and technologies all combined to transform the nature of biological development. Human embryos went from a highly descriptive, static, and private object to that of sometimes contentious public figure. I contend that an ignored source for helping move embryos into the public realm is schoolbooks. Throughout the 1900s, authors and publishers accomplished this by placing biology textbook embryos and

  20. Effect of microbiological fertilizer and soil additive on yield of buckwheat (Fagopyrum esculentum Moenchunder high altitude conditions

    Directory of Open Access Journals (Sweden)

    Oljača Snežana

    2012-01-01

    Full Text Available Effect of microbiological fertilizer (Slavol and soil additives (zeolite and hydrogel on buckwheat (Fagopyrum esculentum Moench yield was investigated in this paper. Trial was set up in the village of Radijevići, Serbia in agroecological conditions of mountain Zlatar (altitude 1,065 m during a two-year period 2009 and 2010. A randomized complete block design with four replications was set up. In organic cropping system three combinations of microbiological fertilizer (Slavol with zeolite and hydrogel were used prior to sowing. Different combinations of the microbiological fertilizer and the soil additives gave positive results especially in the second year of the trial. The best combination in organic cropping system was Slavol+hydrogel with foliar application of the microbiological fertilizer, which resulted in the greatest yield of buckwheat and this treatment can be recommended to producers. Buckwheat performed very well under limited conditions of acidic soil on high altitude in organic cropping system and it can be recommended as a very suitable crop for organic producers.

  1. Effects of nationwide addition of selenium to fertilizers on foods, and animal and human health in Finland: From deficiency to optimal selenium status of the population.

    Science.gov (United States)

    Alfthan, Georg; Eurola, Merja; Ekholm, Päivi; Venäläinen, Eija-Riitta; Root, Tarja; Korkalainen, Katja; Hartikainen, Helinä; Salminen, Pirjo; Hietaniemi, Veli; Aspila, Pentti; Aro, Antti

    2015-01-01

    Despite different geological features the Nordic countries are generally selenium-poor areas. In each country various factors such as food importation and life-style determine the selenium (Se) intake. Due to an extremely low Se intake in the 1970s in Finland, 0.025 mg/day, an official decision was made in 1984 to supplement multinutrient fertilizers with Se in the chemical form of sodium selenate. Almost all fertilizers used in Finland since 1985 have contained Se. Currently all crop fertilizers contain 15 mg Se/kg. Finland is still the only country to take this country-wide measure. In a national monitoring programme, sampling of cereals, basic foodstuffs, feeds, fertilizers, soils, and human tissues has been carried out annually since 1985 by four governmental research organizations. Sampling of foods has been done four times per year and human blood has been obtained annually from the same (n=60) adults. The accuracy of analyses has been verified by annual interlaboratory quality control. During this programme the selenium concentration of spring cereals has increased on average 15-fold compared with the level before the Se fertilization. The mean increase in the Se concentration in beef, pork and milk was 6-, 2- and 3-fold. In terms of Se, organically grown foods of plant origin are generally comparable to products produced before the Se supplementation of fertilizers. Milk from organically fed cows is 50% lower in Se than the usual milk. The average dietary human intake increased from 0.04 mg Se/day/10 MJ in 1985 to a present plateau of 0.08 mg Se/day/10 MJ, which is well above the current nutrition recommendations. Foods of animal origin contribute over 70% of the total daily Se intake. The mean human plasma Se concentration increased from 0.89 μmol/L to a general level of 1.40 μmol/L that can be considered to be an optimal status. The absence of Se deficiency diseases and a reference population have made conclusions on the impact on human health difficult

  2. SUHARTO’S POPULATION POLICY IN CONTEMPORARY INDONESIA : FAMILY PLANNING PROGRAM, MARRIAGE ACT OR COMPULSORY EDUCATION HAS THE GREATEST IMPACT TO FERTILITY DECLINE?

    Directory of Open Access Journals (Sweden)

    Dyah Anantalia Widyastari

    2016-05-01

    Full Text Available Fertility in Indonesia has been falling significantly, from an average total fertility rate of 5.6 children per women in 1970s to 4.1 in 1980, and 2.6 in 2010. This paper attempts to explore which and how Suharto’s population policies have played role in Indonesia’s fertility decline. Whilst the adoption of modern contraceptive was perceived as the major determinant of fertility decline in Indonesia, changes in Indonesia’s political order and socio-economic development also contribute a considerable effect to Indonesians’ familial norms. The implementation of 9-year compulsory education had placed a strong foundation for the future Indonesian human capital and enabled women to obtain higher opportunities for schooling. Beside facilitates the diffusion of ideas among young people and opened up their perspective toward reproductive rights and self actualization, education also increases women’s opportunities to participate in laborforce. With the increasing roles outside the domestic sector, delaying age of marriage and limiting family size becomes a choice for women in contemporary Indonesia. The marriage act, however, was perceived as an accelerator rather than a predictor in increasing age of first marriage. Regardless the existence of the Marriage Law 1974, age of first marriage is likely to increase with increasing of education, although maybe in a slower rate.

  3. Population-based Semen Analysis Results and Fertility Among Patients With Inflammatory Bowel Disease: Results From Subfertility Health Assisted Reproduction and the Environment (SHARE) Study.

    Science.gov (United States)

    Martin, Luke; Mullaney, Sheala; Peche, William; Peterson, Kathryn; Chan, Stephanie; Morton, Ryan; Wan, Yuan; Zhang, Chong; Presson, Angela P; Emery, Benjamin; Aston, Kenneth; Jenkins, Timothy; Carrell, Douglas; Hotaling, James

    2017-09-01

    To evaluate male fertility in Crohn disease (CD) and ulcerative colitis (UC) by examining semen analysis results and paternity from the SHARE study (Subfertility Health Assisted Reproduction and the Environment), a population-based cohort of semen analysis results from Utah men. A population-based cohort of men with CD or UC was identified using the Utah Population Database (contains person-level linked demographic, genealogical, and medical record information for 85% of Utahans) from 1996 to 2014, and validated by clinical chart review. This cohort was then cross-linked (n = 55) to the SHARE population dataset of semen analysis results. Men with CD or UC were compared with population-based, age-matched, paired (1:1) controls (n = 47). Paternity was evaluated though presence and number of linked offspring and inter-birth interval. Offspring were identified in 71% of UC patients (mean of 1.8 children) and 61% of CD patients (mean of 1.2 children). Compared with matched controls, there were no differences in number of offspring, mean inter-birth interval, or any of the evaluated semen analysis parameters among either men with CD or UC. Fertility and semen analysis values among men with UC or CD are not significantly impacted compared with population-based, age-matched controls. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Development of a High Irradiance LED Configuration for Small Field of View Motion Estimation of Fertilizer Particles

    Directory of Open Access Journals (Sweden)

    Simon Cool

    2015-11-01

    Full Text Available Better characterization of the fertilizer spreading process, especially the fertilizer pattern distribution on the ground, requires an accurate measurement of individual particle properties and dynamics. Both 2D and 3D high speed imaging techniques have been developed for this purpose. To maximize the accuracy of the predictions, a specific illumination level is required. This paper describes the development of a high irradiance LED system for high speed motion estimation of fertilizer particles. A spectral sensitivity factor was used to select the optimal LED in relation to the used camera from a range of commercially available high power LEDs. A multiple objective genetic algorithm was used to find the optimal configuration of LEDs resulting in the most homogeneous irradiance in the target area. Simulations were carried out for different lenses and number of LEDs. The chosen configuration resulted in an average irradiance level of 452 W/m2 with coefficient of variation less than 2%. The algorithm proved superior and more flexible to other approaches reported in the literature and can be used for various other applications.

  5. Modeling residential lawn fertilization practices: integrating high resolution remote sensing with socioeconomic data

    Science.gov (United States)

    Weiqi Zhou; Austin Troy; Morgan. Grove

    2008-01-01

    This article investigates how remotely sensed lawn characteristics, such as parcel lawn area and parcel lawn greenness, combined with household characteristics, can be used to predict household lawn fertilization practices on private residential lands. This study involves two watersheds, Glyndon and Baisman's Run, in Baltimore County, Maryland, USA. Parcel lawn...

  6. Understanding variation in human fertility: what can we learn from evolutionary demography?

    Science.gov (United States)

    Sear, Rebecca; Lawson, David W; Kaplan, Hillard; Shenk, Mary K

    2016-04-19

    Decades of research on human fertility has presented a clear picture of how fertility varies, including its dramatic decline over the last two centuries in most parts of the world. Why fertility varies, both between and within populations, is not nearly so well understood. Fertility is a complex phenomenon, partly physiologically and partly behaviourally determined, thus an interdisciplinary approach is required to understand it. Evolutionary demographers have focused on human fertility since the 1980s. The first wave of evolutionary demographic research made major theoretical and empirical advances, investigating variation in fertility primarily in terms of fitness maximization. Research focused particularly on variation within high-fertility populations and small-scale subsistence societies and also yielded a number of hypotheses for why fitness maximization seems to break down as fertility declines during the demographic transition. A second wave of evolutionary demography research on fertility is now underway, paying much more attention to the cultural and psychological mechanisms underpinning fertility. It is also engaging with the complex, multi-causal nature of fertility variation, and with understanding fertility in complex modern and transitioning societies. Here, we summarize the history of evolutionary demographic work on human fertility, describe the current state of the field, and suggest future directions. © 2016 The Author(s).

  7. Can human populations be stabilized?

    Science.gov (United States)

    Warren, Stephen G.

    2015-02-01

    Historical examples of demographic change, in China, Italy, Nigeria, Utah, Easter Island, and elsewhere, together with simple mathematics and biological principles, show that stabilizing world population before it is limited by food supply will be more difficult than is generally appreciated. United Nations population projections are wrong because they assume, in spite of the absence of necessary feedbacks, that all nations will converge rapidly to replacement-level fertility and thereafter remain at that level. Education of women and provision of contraceptives have caused dramatic reductions in fertility, but many groups, including some that are well-educated, maintain high fertility. Small groups with persistent high fertility can grow to supplant low-fertility groups, resulting in continued growth of the total population. The global average fertility rate could rise even if each country's fertility rate is falling. In some low-fertility European countries where deaths exceed births, the population continues to grow because of immigration. Producing more than two offspring is normal for all animal species with stable populations because their populations are limited by resources or predation rather than birth control. It may therefore be appropriate to view the growth of human population as the result not of excess fertility but rather of excess food.

  8. Finding the Balance: Fertility Control for the Management of Fragmented Populations of a Threatened Rock-Wallaby Species

    OpenAIRE

    Nicole Willers; Martin, Graeme B.; Phill Matson; Mawson, Peter R.; Keith Morris; Roberta Bencini

    2015-01-01

    Simple Summary Black-flanked rock-wallabies (Petrogale lateralis lateralis) can reach high numbers in fragmented populations in the West Australian wheat-belt, where they can damage crops and cause habitat degradation. As they are threatened, we wanted a non-permanent control method that did not adversely affect the body condition of treated females compared to untreated females, using body condition as an indicator of general health and fitness. We gave adult female rock-wallabies deslorelin...

  9. PHOSPHATE AND POTASSIUM FERTILIZATION FOR RADISH GROWN IN A LATOSOL WITH A HIGH CONTENT OF THESE NUTRIENTS

    Directory of Open Access Journals (Sweden)

    ARTHUR BERNARDES CECÍLIO FILHO

    2017-01-01

    Full Text Available The intensive cultivation of vegetables with frequent chemical fertilization may cause accumulation of nutrients in the soil. This, in turn, may reduce crop yields and damage the environment due to contamination of ground water and rivers. Thus, to increase the effects of P (0, 100, 200, 300 and 400 kg ha - 1 of P 2 O 5 and K (0, 60, 120, 180 and 240 kg ha - 1 of K 2 O doses on the growth and productivity of radish cultivars (Sakata 19 and Sakata 25 in a soil with high levels of these nutrients, two experiments were conducted in randomized blocks with the factors cultivars and doses arranged in a 2 x 5 factorial design with three replications. Number of leaves per plant, leaf area, shoot and root dry mass, total and commercial productivity, percentage of cracked roots and P and K contents in the plant and in the soil were evaluated. The Sakata 19 cultivar performed better than the Sakata 25 in both experiments. The fertilization with P or K did not influence the growth and the productivity of both radish cultivars. Therefore, both cultivars of radish evaluated do not need to be fertilized with P and K when planted in a Latosol with high levels of these nutrients.

  10. Children's stunting in sub-Saharan Africa: Is there an externality effect of high fertility?

    Directory of Open Access Journals (Sweden)

    Øystein Kravdal

    2011-09-01

    Full Text Available A positive relationship between the number of siblings and a child's chance of being stunted has been seen in several studies. It is possible that individual stunting risks are also raised by high fertility in the community, partly because of the impact of aggregate fertility on the local economy, but this issue has not been addressed in earlier investigations. In this study we estimate the independent effect of the child dependency ratio in the province (or governorate, region, or larger geopolitical zone within a country, using DHS data on up to 145,000 children in 152 provinces in 23 countries with at least two such surveys. The data design allows inclusion of lagged province variables and province fixed effects (to control for constant unobserved province characteristics. Three types of regression models for a child's chance of being stunted are estimated. Some estimates suggest an adverse effect of the current child dependency ratio, net of the child's number of siblings, while others do not point in this direction. When the child dependency ratio measured in an earlier survey is included instead, no significant effects appear. Thus, we conclude that there is only weak support for the idea that a child's stunting risk may be raised by high fertility in the community.

  11. Fertility treatment and reproductive health of male offspring: a study of 1,925 young men from the general population

    DEFF Research Database (Denmark)

    Jensen, Tina Kold; Jørgensen, Niels; Asklund, Camilla

    2007-01-01

    Little is known the about the reproductive health of offspring after fertility treatment. In 2001-2005, the authors approached young Danish men attending a compulsory physical examination to determine their fitness for military service. A total of 1,925 men volunteered, delivered a semen sample...

  12. Physical Cues of Ovulatory Status: A Failure to Replicate Enhanced Facial Attractiveness and Reduced Waist-to-Hip Ratio at High Fertility

    Directory of Open Access Journals (Sweden)

    April Bleske-Rechek

    2011-07-01

    Full Text Available We investigated women's facial attractiveness and body shape as a function of menstrual cycle phase, with the expectation from previous research that both would be enhanced during the high fertile phase. To control for the effects of women's daily behaviors on their appearance and waistline, we visited 37 normally cycling women twice in their dorm, where we photographed and measured them at low and high fertile days of their cycle immediately upon their waking. Seventy-four judges from a separate institution chose, for each woman, the picture they thought was more attractive. We analyzed a subset of 20 women who, by forward counting, had a High Fertility visit between Days 10–13 and a Low Fertility visit between Days 20–23; and we also analyzed a subsample of 17 women who, by reverse counting, had a High Fertility visit on the days leading to ovulation and a Low Fertility visit one week after ovulation. In neither set of analyses were women's waist-to-hip ratios lower nearer ovulation, and in neither set were women's high fertile pictures chosen at an above-chance rate by either male or female judges. We did not find evidence that facial attractiveness and waist-to-hip ratio are reliable physical cues of ovulatory status.

  13. Physical cues of ovulatory status: a failure to replicate enhanced facial attractiveness and reduced waist-to-hip ratio at high fertility.

    Science.gov (United States)

    Bleske-Rechek, April; Harris, Heather D; Denkinger, Kelly; Webb, Rose Mary; Erickson, Leah; Nelson, Lyndsay A

    2011-08-24

    We investigated women's facial attractiveness and body shape as a function of menstrual cycle phase, with the expectation from previous research that both would be enhanced during the high fertile phase. To control for the effects of women's daily behaviors on their appearance and waistline, we visited 37 normally cycling women twice in their dorm, where we photographed and measured them at low and high fertile days of their cycle immediately upon their waking. Seventy-four judges from a separate institution chose, for each woman, the picture they thought was more attractive. We analyzed a subset of 20 women who, by forward counting, had a High Fertility visit between Days 10-13 and a Low Fertility visit between Days 20-23; and we also analyzed a subsample of 17 women who, by reverse counting, had a High Fertility visit on the days leading to ovulation and a Low Fertility visit one week after ovulation. In neither set of analyses were women's waist- to-hip ratios lower nearer ovulation, and in neither set were women's high fertile pictures chosen at an above-chance rate by either male or female judges. We did not find evidence that facial attractiveness and waist-to-hip ratio are reliable physical cues of ovulatory status.

  14. High resolution population estimates from telecommunications data

    National Research Council Canada - National Science Library

    Douglass, Rex W; Meyer, David A; Ram, Megha; Rideout, David; Song, Dongjin

    2015-01-01

    .... Despite the broad relevance and importance of such data, acquiring local census estimates in a timely and accurate manner is challenging because population counts can change rapidly, are often...

  15. IUSSP activities: Committee on Fertility and Family Planning. Implications of the International Conference on Population and Development (ICPD) Programme of Action for the IUSSP.

    Science.gov (United States)

    Phillips, J

    1996-05-01

    This article provides an overview of some emerging research issues on population and development, appropriate program design, the impact of family planning programs, and a tentative agenda for forthcoming International Union for Scientific Study of Population (IUSSP) seminars. The 1994 Plan of Action from the International Conference on Population and Development (ICPD) in Cairo challenges the population research community. This article addresses the implications of the 1994 Plan for the IUSSP Fertility and Family Planning Committee. The Cairo ICPD policy consensus confirmed the impact of family planning programs over the decades. The conference shifted the focus to research on how family planning programs manifest this impact and who benefits. The IUSSP committee will focus on the efficiency of the investment in programs, the relevance of programs to demand-constrained economies, sustainability of programs, the appropriate design and organization of programs, and social impacts of family planning. The committee plans to hold three seminars on the aforementioned topics. The IUSSP General Conference in Beijing plans to review the literature on theories of measurement and the social impact of family planning programs. Papers at the Beijing conference will stress the impact of family planning programs on social institutions and empowerment, unmet need for contraception, and male roles. The Fertility and Family Planning Committee will discuss fertility trends and determinants in South Asia, social institutions and family planning programs in sub-Saharan Africa, and methods for evaluating family planning programs at the first committee meeting. A textbook is planned for late 1996 on methods for evaluation of family planning programs. Sub-Saharan African family planning programs must be adapted to the rapidly spreading AIDS epidemic. The Committee on AIDS will be offering an exploratory workshop on policy issues and research needs on the implications of the AIDS crisis

  16. Ethnic Dimensions of Guatemala's Stalled Transition: A Parity-Specific Analysis of Ladino and Indigenous Fertility Regimes.

    Science.gov (United States)

    Grace, Kathryn; Sweeney, Stuart

    2016-02-01

    In some contemporary populations, fertility levels appear to plateau, with women maintaining a consistently high level of fertility for a relatively extended period. Because this plateau does not reflect the historical patterns observed in Europe, the focus of most studies on fertility patterns, mechanisms underlying the plateau and the reinstatement of a decline have not been fully explored and are not fully understood. Through the construction of fertility histories of 25,000 women using multiple years of health survey data, we analyze some of the components of stalled fertility as they pertain to Guatemala, the only Central American country to have experienced a stalled fertility decline.

  17. Risk for borderline ovarian tumours after exposure to fertility drugs: results of a population-based cohort study.

    Science.gov (United States)

    Bjørnholt, Sarah Marie; Kjaer, Susanne Krüger; Nielsen, Thor Schütt Svane; Jensen, Allan

    2015-01-01

    Do fertility drugs increase the risk for borderline ovarian tumours, overall and according to histological subtype? The use of any fertility drug did not increase the overall risk for borderline ovarian tumours, but an increased risk for serous borderline ovarian tumours was observed after the use of progesterone. Many epidemiological studies have addressed the connection between fertility drugs use and risk for ovarian cancer; most have found no strong association. Fewer studies have assessed the association between use of fertility drugs and risk for borderline ovarian tumours, and the results are inconsistent. A retrospective case-cohort study was designed with data from a cohort of 96 545 Danish women with fertility problems referred to all Danish fertility clinics in the period 1963-2006. All women were followed for first occurrence of a borderline ovarian tumour from the initial date of infertility evaluation until a date of migration, date of death or 31 December 2006, whichever occurred first. The median length of follow-up was 11.3 years. Included in the analyses were 142 women with borderline ovarian tumours (cases) and 1328 randomly selected sub-cohort members identified in the cohort during the follow-up through 2006. Cases were identified by linkage to the Danish Cancer Register and the Danish Register of Pathology by use of personal identification numbers. To obtain information on use of fertility drugs, hospital files and medical records of infertility-associated visits to all Danish fertility clinics were collected and supplemented with information from the Danish IVF register. We used case-cohort techniques to calculate rate ratios (RRs) and corresponding 95% confidence intervals (CIs) for borderline ovarian tumours, overall and according to histological subtype, associated with the use of any fertility drug or five specific groups of fertility drugs: clomiphene citrate, gonadotrophins (human menopausal gonadotrophins and follicle

  18. Experimental and genetic analyses reveal that inbreeding depression declines with increased self-fertilization among populations of a coastal dune plant.

    Science.gov (United States)

    Dart, S; Eckert, C G

    2013-03-01

    Theory predicts that inbreeding depression (ID) should decline via purging in self-fertilizing populations. Yet, intraspecific comparisons between selfing and outcrossing populations are few and provide only mixed support for this key evolutionary process. We estimated ID for large-flowered (LF), predominantly outcrossing vs. small-flowered (SF), predominantly selfing populations of the dune endemic Camissoniopsis cheiranthifolia by comparing selfed and crossed progeny in glasshouse environments differing in soil moisture, and by comparing allozyme-based estimates of the proportion of seeds selfed and inbreeding coefficient of mature plants. Based on lifetime measures of dry mass and flower production, ID was stronger in nine LF populations [mean δ = 1-(fitness of selfed seed/fitness of outcrossed seed) = 0.39] than 16 SF populations (mean δ = 0.03). However, predispersal ID during seed maturation was not stronger for LF populations, and ID was not more pronounced under simulated drought, a pervasive stress in sand dune habitat. Genetic estimates of δ were also higher for four LF (δ = 1.23) than five SF (δ = 0.66) populations; however, broad confidence intervals around these estimates overlapped. These results are consistent with purging, but selective interference among loci may be required to maintain strong ID in partially selfing LF populations, and trade-offs between selfed and outcrossed fitness are likely required to maintain outcrossing in SF populations. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  19. Biogas final digestive byproduct applied to croplands as fertilizer contains high levels of steroid hormones

    DEFF Research Database (Denmark)

    Rodriguez-Navas, Carlos; Björklund, Erland; Halling-Sørensen, Bent

    2013-01-01

    In this study we evaluate and demonstrate the occurrence of nine natural and one synthetic steroid hormone, including estrogens, androgens and progestagens in biogas final digestate byproduct (digestion liquid) commonly used as an agricultural fertilizer. We investigated two biogas sites that uti......In this study we evaluate and demonstrate the occurrence of nine natural and one synthetic steroid hormone, including estrogens, androgens and progestagens in biogas final digestate byproduct (digestion liquid) commonly used as an agricultural fertilizer. We investigated two biogas sites....... Evaluation of the potential environmental burden through the application in agriculture was also assessed on the basis of predicted environmental concentrations. This study indicates that the biogas digestion process does not completely remove steroid hormones from livestock manure and use of final digestate...

  20. Fertilizer trends

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, R.

    1992-12-31

    This fourteenth edition of Fertilizer Trends presents historical fertilizer market data to aid industry, government, and financial market analysis and planners in their study of fertilizer and agricultural market cycles, market planning, and investment decisions. A 27-year summary of the US fertilizer market is presented in graphic and tabular form. Production, use, and trade data are included for each plant nutrient and sulfur. Canadian statistics have been included because of the important role of the Canadian fertilizer industry in the US fertilizer market. World production and consumption of nitrogen, phosphate, and potash are included because of the strong influence of world markets on the domestic market. Planted acreage and plant nutrient application rates for the major crops have been included to illustrate their effect on fertilizer use. Retail prices of the leading US fertilizer materials also are given.

  1. Correlations in fertility across generations: can low fertility persist?

    Science.gov (United States)

    Kolk, Martin; Cownden, Daniel; Enquist, Magnus

    2014-01-01

    Correlations in family size across generations could have a major influence on human population size in the future. Empirical studies have shown that the associations between the fertility of parents and the fertility of children are substantial and growing over time. Despite their potential long-term consequences, intergenerational fertility correlations have largely been ignored by researchers. We present a model of the fertility transition as a cultural process acting on new lifestyles associated with fertility. Differences in parental and social influences on the acquisition of these lifestyles result in intergenerational correlations in fertility. We show different scenarios for future population size based on models that disregard intergenerational correlations in fertility, models with fertility correlations and a single lifestyle, and models with fertility correlations and multiple lifestyles. We show that intergenerational fertility correlations will result in an increase in fertility over time. However, present low-fertility levels may persist if the rapid introduction of new cultural lifestyles continues into the future. PMID:24478294

  2. [Percentage of births and fertility rates in adolescents in Mexico (2008-2012): stratification and priorization of municipalities with high risk].

    Science.gov (United States)

    Reyes-Pablo, Adelmo Eloy; Navarrete-Hernández, Eduardo; Canún-Serrano, Sonia; Valdés-Hernández, Javier

    2015-12-01

    Mexico in 2008 was designed as the first place of adolescent pregnancy at the Organization for Economic Cooperation and Development, with specific fertility rate (SFR) for 15-1 9years of age of 64.2/1,000 woman at the same age. Estimate of percentage births and SFR in adolescent population at national, state and municipal level in Mexico in 2008-2012 at the total group of adolescents 10 to 1 9 years old and by subgroups of 10-14 and 15 tol 9 years old, identifying the priority municipalities with adolescence pregnancies. Data bases of certificates of live birth and fetal death with gestational age of 22-45 weeks were joined in 2008-2012. A data base of 1 0'585,032 births in 2008-2012 was obtained, 98.9% were live births and 1.1% was stillbirths. The SFR nationwide for the period 2008-2012 were of the order of 3.l for the group of 10-1 4years, 75.3 for 15-19, 39.6 for the total group of 10-19 years and 66.1 for 20 to 49 years per 1000 women for the same age. In the last decade it has increased teen pregnancy as well as the percentage of births and the fertility rate in this age group, worrying situation for the high risk of biological, psychological and social damage that pregnancy early.

  3. Fertility treatments and pediatric neoplasms of the offspring: results of a population-based cohort with a median follow-up of 10 years.

    Science.gov (United States)

    Wainstock, Tamar; Walfisch, Asnat; Shoham-Vardi, Ilana; Segal, Idit; Harlev, Avi; Sergienko, Ruslan; Landau, Daniella; Sheiner, Eyal

    2017-03-01

    Studies have questioned the long-term health effects of offspring conceived after fertility treatments. We aimed to evaluate whether an association exists between mode of conception (in vitro fertilization, ovulation induction, or spontaneous pregnancy) and neoplasm risk (both benign and malignant tumors) among the offspring; we observed the offspring for up to 18 years. A population-based cohort analysis was performed that compared the risk for neoplasms among children (up to the age of 18 years) based on mode of conception. Neoplasm diagnoses were based on hospital records of the same single tertiary center in the region. All singletons born during from 1991-2013 and discharged alive were included in the study. Offspring with congenital malformations were excluded from the analysis. Kaplan-Meier survival curves were constructed to compare cumulative neoplasms incidence; multivariable survival analyses were used to control for confounders that included gestational age, pregnancy complications, and maternal factors. During the study period, 242,187 newborn infants met the inclusion criteria: 2603 (1.1%) were conceived after in vitro fertilization; 1721 (0.7%) were conceived after ovulation induction treatments, and 237,863 (98.3%) were conceived spontaneously. During the follow-up period (median, 10.55 years), 1498 neoplasms(0.6%) were diagnosed. Incidence density rate for neoplasms was higher among children conceived either after in vitro fertilization (1.5/1000 person years) or ovulation induction treatments (1.0/1000 person years), as compared with naturally conceived children (0.59/1000 person years; Kaplan-Meier log rank, Pneoplasms and the association between any fertility treatments and malignancies remained significant; we controlled for confounders such as gestational diabetes mellitus, hypertensive disorders, preterm birth, and maternal age (adjusted hazard ratio, 2.48; 95% confidence interval, 1.71-3.50; and adjusted hazard ratio, 1.96; 95

  4. Fertility Awareness

    Science.gov (United States)

    ... in the Holiday Spirit Cold-Weather Sports Fertility Awareness KidsHealth > For Teens > Fertility Awareness Print A A A What's in this article? ... español Monitoreo de fertilidad What Is It? Fertility awareness is a way to prevent pregnancy by not ...

  5. Mapping QTLs for Fertility Restoration of Different Cytoplasmic Male Sterility Types in Rice Using Two Oryza sativa ×O. rufipogon Backcross Inbred Line Populations.

    Science.gov (United States)

    Hu, Biao-Lin; Xie, Jian-Kun; Wan, Yong; Zhang, Jin-Wei; Zhang, Fan-Tao; Li, Xia

    2016-01-01

    Hybrid rice breeding using cytoplasmic male sterility/fertility restoration (CMS/Rf) systems plays an important role in ensuring global food security. Two backcross inbred line (BIL) populations derived from either Xieqingzao B (XB)//XB/Dongxiang wild rice (DWR) (XXD) or XB//DWR/XB (XDX) were used to detect quantitative trait loci (QTLs) for fertility restoration of Dwarf wild abortive- (DA-), Indonesia Paddy- (ID-), and DWR-type CMS in rice. Lines with ID- and DA-type CMS were testcrossed with both the XXD- and XDX-BILs, while the line with DWR-type CMS was testcrossed with the XDX-BILs only. A total of 16 QTLs for fertility restoration of CMS systems were identified, including three for DWR-type CMS, six for DA-type CMS, and seven for ID-type CMS. All of the additive alleles in the QTLs were derived from Oryza rufipogon. Eleven QTLs were clustered in five chromosomal regions, indicating that common Rf loci restored different CMS systems, and the favorable O. rufipogon alleles could be used to develop restorer lines for various CMS types by marker-assisted selection.

  6. Physical Cues of Ovulatory Status: A Failure to Replicate Enhanced Facial Attractiveness and Reduced Waist-to-Hip Ratio at High Fertility

    National Research Council Canada - National Science Library

    Bleske-Rechek, April; Harris, Heather D; Denkinger, Kelly; Webb, Rose Mary; Erickson, Leah; Nelson, Lyndsay A

    2011-01-01

    We investigated women's facial attractiveness and body shape as a function of menstrual cycle phase, with the expectation from previous research that both would be enhanced during the high fertile phase...

  7. Phytophthora infestans field isolates from Gansu Province, China are genetically highly diverse and show a high frequency of self fertility

    NARCIS (Netherlands)

    Han, M.; Liu, G.; Li, J.P.; Govers, F.; Zhu, X.Q.; Shen, C.Y.; Guo, L.Y.

    2013-01-01

    The genetic diversity of 85 isolates of Phytophthora infestans collected in 2007 from Gansu province in China was determined and compared with 21 isolates collected before 2004. Among them, 70 belonged to the A1 mating type and 15 were self-fertile (SF). The mitochondrial DNA haplotypes revealed

  8. Physical Cues of Ovulatory Status: A Failure to Replicate Enhanced Facial Attractiveness and Reduced Waist-to-Hip Ratio at High Fertility

    OpenAIRE

    April Bleske-Rechek; Heather D. Harris; Kelly Denkinger; Rose Mary Webb; Leah Erickson; Lyndsay A. Nelson

    2011-01-01

    We investigated women's facial attractiveness and body shape as a function of menstrual cycle phase, with the expectation from previous research that both would be enhanced during the high fertile phase. To control for the effects of women's daily behaviors on their appearance and waistline, we visited 37 normally cycling women twice in their dorm, where we photographed and measured them at low and high fertile days of their cycle immediately upon their waking. Seventy-four judges from a sepa...

  9. The Effects of Local and Systemic Growth Hormone Treatment on Germ Cell Population and Fertility in an Experimental Unilateral Testicular Torsion and Orchiectomy Model.

    Science.gov (United States)

    Ates, Ufuk; Gollu, Gulnur; Bingol-Kologlu, Meltem; Billur, Deniz; Kucuk, Gonul; Oruklu, Nihan; Bagrıacik, Umit; Hasırcı, Nesrin; Dindar, Hüseyin

    2015-12-01

    We evaluated the effects of local and systemic growth hormone on the germ cell population of the contralateral testes of pubertal rats subjected to unilateral testicular torsion and orchiectomy 24 hours later. A total of 40 male Wistar-Albino rats at age 3 weeks were divided into 5 groups. In the sham operated group the right testis was sutured and orchiectomy was performed 24 hours later. In groups 2 to 5 orchiectomy was performed 24 hours later following testicular torsion. In groups 3 and 4 unloaded and growth hormone loaded gelatin films, respectively, were sutured on the contralateral testes. In group 5 systemic growth hormone was administered for 7 days. Five weeks later each rat was cohabited with 2 female rats and the left testes were removed for evaluation. Mean seminiferous tubular diameter, mean testicular biopsy score and the mean haploid cell percentage were calculated. Mating studies were performed and fertility parameters were assayed. Mean seminiferous tubular diameter, mean testicular biopsy score and the mean haploid cell percentage of the contralateral testes were significantly decreased in the control and gelatin groups compared with the other groups. There was no difference between the local and systemic growth hormone groups regarding the haploid cell percentage. There were no differences between the groups in mean fetus numbers, mating or fertility and fecundity indexes except in the gelatin group, in which the mean fetus number was significantly lower. Fertility is not affected in rats after 24 hours of testicular torsion and orchiectomy, although there is germ cell injury and a decrease in the percent of haploid cells. Growth hormone administration resulted in the restoration of germ cell histology and an increase in the haploid cell percentage of the contralateral testes. Growth hormone may improve fertility after unilateral testicular torsion and orchiectomy. Copyright © 2015 American Urological Association Education and Research, Inc

  10. Comparison between a sire model and an animal model for genetic evaluation of fertility traits in Danish Holstein population

    DEFF Research Database (Denmark)

    Sun, C; Madsen, P; Nielsen, U S

    2009-01-01

    Comparisons between a sire model, a sire-dam model, and an animal model were carried out to evaluate the ability of the models to predict breeding values of fertility traits, based on data including 471,742 records from the first lactation of Danish Holstein cows, covering insemination years from...... the results suggest that the animal model, rather than the sire model, should be used for genetic evaluation of fertility traits......Comparisons between a sire model, a sire-dam model, and an animal model were carried out to evaluate the ability of the models to predict breeding values of fertility traits, based on data including 471,742 records from the first lactation of Danish Holstein cows, covering insemination years from...... (EBV) from the animal model and the sire-dam model were close to 1 for all the traits, and those between the animal model and the sire model ranged from 0.95 to 0.97. Model ability to predict sire breeding value was assessed using 4 criteria: 1) the correlation between sire EBV from 2 data subsets...

  11. Microbial populations and hydrocarbon biodegradation potentials in fertilized shoreline sediments affected by the T/V Exxon Valdez oil spill.

    Science.gov (United States)

    Lindstrom, J E; Prince, R C; Clark, J C; Grossman, M J; Yeager, T R; Braddock, J F; Brown, E J

    1991-09-01

    The effort of clean up the T/V Exxon Valdez oil spill in Prince William Sound, Alaska, included the use of fertilizers to accelerate natural microbial degradation of stranded oil. A program to monitor various environmental parameters associated with this technique took place during the summer of 1990. Microbiological assays for numbers of heterotrophic and oil-degrading microbes and their hydrocarbon mineralization potentials were performed in support of this program. Fertilizer addition resulted in higher hexadecane and phenanthrene mineralization potentials on treated plots than on untreated reference plots. Microbial numbers in treated and reference surface sediments were not significantly different immediately after the first nutrient application in May 1990. However, subsurface sediments from treated plots had higher numbers of hydrocarbon degraders than did reference sediments shortly after treatment. The second application of fertilizer, later in summer, resulted in surface and subsurface increases in numbers of hydrocarbon degraders with respect to reference sediments at two of the three study sites. Elevated mineralization potentials, coupled with increased numbers of hydrocarbon degraders, indicated that natural hydrocarbon biodegradation was enhanced. However, these microbiological measurements alone are not sufficient to determine in situ rates of crude oil biodegradation.

  12. Chinese culture and fertility decline.

    Science.gov (United States)

    Wu, C; Jia, S

    1992-01-01

    Coale has suggested that cultural factors exert a significant influence on fertility reduction; countries in the "Chinese cultural circle" would be the first to show fertility decline. In China, the view was that traditional Chinese culture contributed to increased population. This paper examines the nature of the relationship between Chinese culture and fertility. Attention was directed to a comparison of fertility rates of developing countries with strong Chinese cultural influence and of fertility within different regions of China. Discussion was followed by an explanation of the theoretical impact of Chinese culture on fertility and direct and indirect beliefs and practices that might either enhance or hinder fertility decline. Emigration to neighboring countries occurred after the Qing dynasty. Fertility after the 1950s declined markedly in Japan, Singapore, Hong Kong, South Korea, Taiwan, and mainland China: all countries within the Chinese cultural circle. Other countries within the Chinese circle which have higher fertility, yet lower fertility than other non-Chinese cultural countries, are Malaysia, Thailand, and Indonesia. Within China, regions with similar fertility patterns are identified as coastal regions, central plains, and mountainous and plateau regions. The Han ethnic group has lower fertility than that of ethnic minorities; regions with large Han populations have lower fertility. Overseas Chinese in East Asian countries also tend to have lower fertility than their host populations. Chinese culture consisted of the assimilation of other cultures over 5000 years. Fertility decline was dependent on the population's desire to limit reproduction, favorable social mechanisms, and availability of contraception: all factors related to economic development. Chinese culture affects fertility reduction by affecting reproductive views and social mechanisms directly, and indirectly through economics. Confucianism emphasizes collectivism, self

  13. Abundance and dispersal of Heteronychus arator (Coleoptera: Scarabaeidae) in maize fields under different fertilizer treatments

    National Research Council Canada - National Science Library

    Abdallah, M; Mwatawala, M W; Kudra, A B

    2016-01-01

    .... The abundance of adults varied with time, with high peaks recorded in January. Abundance of both larvae and adults were significantly affected by fertilizer type, with high populations in farmyard...

  14. Relationship between the pre- and postpartum body condition scores and periparturient indices and fertility in high-yielding dairy cows

    OpenAIRE

    Stefańska Barbara; Poźniak Agnieszka; Nowak Włodzimierz

    2016-01-01

    Introduction: The aim of this study was to investigate the relationship between body condition score (BCS) determined on the dry-off day, calving day, and in the first month of lactation, its changes during the dry period and early lactation, and periparturient indices and fertility in high-producing dairy cows. Material and Methods: The experiment was conducted in two herds: A and B, located in Western Poland. The studies were conducted on 116 and 108 Polish Holstein-Friesian dairy cows resp...

  15. Recombinant fetuin-B protein maintains high fertilization rate in cumulus cell-free mouse oocytes.

    Science.gov (United States)

    Dietzel, E; Floehr, J; Van de Leur, E; Weiskirchen, R; Jahnen-Dechent, W

    2017-01-01

    Does fetuin-B inhibit premature zona pellucida (ZP) hardening in mouse oocytes in vitro and thus increase IVF rate? Supplementation of oocyte in vitro maturation (IVM) media with recombinant mouse fetuin-B (rmFetuB) increased fertilization rate without affecting mouse embryo development into blastocysts. Mice deficient in fetuin-B are infertile owing to premature ZP hardening. Premature ZP hardening also occurs during oocyte IVM leading to decreased fertilization rate. We fertilized batches of 20-30 mouse metaphase II (Mll) stage oocytes from C57BL/6 mice with fresh sperm, and studied early embryo development until blastocyst hatching. Oocytes were maintained with or without rmFetuB during IVM and IVF. Exogenous rmFetuB was added to media prior to oocyte isolation. ZP hardening was quantified by chymotrypsin digestion timing and by counting attached sperm. In the absence of cumulus cells, rmFetuB dose-dependently inhibited ZP hardening and increased IVF rate (P = 0.039). Fetuin-B at ≥0.03 mg/ml also inhibited physiological, fertilization-triggered ZP hardening (indicated by increased sperm binding, P = 0.0002), without increasing embryo death. Exogenous rmFetuB increased IVF rate for up to 5 hours of IVM (P = 0.02 at 1 hour, P = 0.01 at 5 hours of IVM). Mll stage oocytes in this study were isolated from the ampullae of fetuin-B expressing mice. Thus, oocytes were protected against premature ZP hardening by endogenous fetuin-B. In humans and livestock, oocytes are usually isolated by follicle puncture before ovulation. In this situation, the deprivation of endogenous fetuin-B would occur earlier and the effect of exogenous fetuin-B in the IVF medium may be even more pronounced. Fertilization-triggered ZP hardening is essential for embryo development but in this study the effect of fetuin-B supplementation was only studied to blastocyst stage. Any influence of added fetuin-B on later embryo development after transplantation remains to be determined. The astacin

  16. Albumin is synthesized in epididymis and aggregates in a high molecular mass glycoprotein complex involved in sperm-egg fertilization.

    Directory of Open Access Journals (Sweden)

    Kélen Fabíola Arroteia

    Full Text Available The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

  17. Albumin is synthesized in epididymis and aggregates in a high molecular mass glycoprotein complex involved in sperm-egg fertilization.

    Science.gov (United States)

    Arroteia, Kélen Fabíola; Barbieri, Mainara Ferreira; Souza, Gustavo Henrique Martins Ferreira; Tanaka, Hiromitsu; Eberlin, Marcos Nogueira; Hyslop, Stephen; Alvares, Lúcia Elvira; Pereira, Luís Antonio Violin Dias

    2014-01-01

    The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

  18. Measuring selective constraint on fertility in human life histories.

    Science.gov (United States)

    Jones, James Holland; Tuljapurkar, Shripad

    2015-07-21

    Human life histories combine late age at first reproduction, long reproductive span, relatively high fertility, and substantial postreproductive survival. However, even among the most fecund populations, human fertility falls far below its theoretical maximum. The extent of parental care required for successful offspring recruitment and widespread fertility decline under proper economic conditions suggest that selection on fertility is constrained by trade-offs with recruitment. Here we measure the trade-offs between life history traits under selection by approximating the slope of the selective constraint curve on two traits at the observed values. Using a selection of populations that span human demographic space, we find that the substitution elasticity of fertility for infant survival shows age-related patterns, with minimum substitution elasticities ranging from 14 to 22 for the four populations. The age of this minimum occurs earlier in the high-mortality populations relative to generation time than it does in the low-mortality populations. The human curves are qualitatively similar to one of two comparable nonhuman primate age-specific substitution elasticity curves. The curve for rhesus macaques has a similar shape but is shifted down, meaning that the threshold for switching from investing in survival to fertility is lower at all ages. The magnitude of the substitution elasticities is similar between chimpanzees and humans but the shape is quite different, rising more slowly for a longer fraction of the chimpanzee life cycle. The steeply rising substitution elasticities with age in humans has clear implications for the evolution of reproductive senescence.

  19. Convergence in fertility of South Africans and Mozambicans in rural South Africa, 1993–2009

    Directory of Open Access Journals (Sweden)

    Michel Garenne

    2013-01-01

    Full Text Available Background: Although there are significant numbers of people displaced by war in Africa, very little is known about long-term changes in the fertility of refugees. Refugees of the Mozambican civil war (1977–1992 settled in many neighbouring countries, including South Africa. A large number of Mozambican refugees settled within the Agincourt sub-district, underpinned by a Health and Socio-demographic Surveillance Site (AHDSS, established in 1992, and have remained there. The AHDSS data provide a unique opportunity to study changes in fertility over time and the role that the fertility of self-settled refugee populations plays in the overall fertility level of the host community, a highly relevant factor in many areas of sub-Saharan Africa. Objectives: To examine the change in fertility of former Mozambican self-settled refugees over a period of 16 years and to compare the overall fertility and fertility patterns of Mozambicans to host South Africans. Design: Prospective data from the AHDSS on births from 1993 to 2009 were used to compare fertility trends and patterns and to examine socio-economic factors that may be associated with fertility change. Results: There has been a sharp decline in fertility in the Mozambican population and convergence in fertility patterns of Mozambican and local South African women. The convergence of fertility patterns coincides with a convergence in other socio-economic factors. Conclusion: The fertility of Mozambicans has decreased significantly and Mozambicans are adopting the childbearing patterns of South African women. The decline in Mozambican fertility has occurred alongside socio-economic gains. There remains, however, high unemployment and endemic poverty in the area and fertility is not likely to decrease further without increased delivery of family planning to adolescents and increased education and job opportunities for women.

  20. Convergence in fertility of South Africans and Mozambicans in rural South Africa, 1993-2009.

    Science.gov (United States)

    Williams, Jill; Ibisomi, Latifat; Sartorius, Benn; Kahn, Kathleen; Collinson, Mark; Tollman, Stephen; Garenne, Michel

    2013-01-24

    Although there are significant numbers of people displaced by war in Africa, very little is known about long-term changes in the fertility of refugees. Refugees of the Mozambican civil war (1977-1992) settled in many neighbouring countries, including South Africa. A large number of Mozambican refugees settled within the Agincourt sub-district, underpinned by a Health and Socio-demographic Surveillance Site (AHDSS), established in 1992, and have remained there. The AHDSS data provide a unique opportunity to study changes in fertility over time and the role that the fertility of self-settled refugee populations plays in the overall fertility level of the host community, a highly relevant factor in many areas of sub-Saharan Africa. To examine the change in fertility of former Mozambican self-settled refugees over a period of 16 years and to compare the overall fertility and fertility patterns of Mozambicans to host South Africans. Prospective data from the AHDSS on births from 1993 to 2009 were used to compare fertility trends and patterns and to examine socio-economic factors that may be associated with fertility change. There has been a sharp decline in fertility in the Mozambican population and convergence in fertility patterns of Mozambican and local South African women. The convergence of fertility patterns coincides with a convergence in other socio-economic factors. The fertility of Mozambicans has decreased significantly and Mozambicans are adopting the childbearing patterns of South African women. The decline in Mozambican fertility has occurred alongside socio-economic gains. There remains, however, high unemployment and endemic poverty in the area and fertility is not likely to decrease further without increased delivery of family planning to adolescents and increased education and job opportunities for women.

  1. Convergence in fertility of South Africans and Mozambicans in rural South Africa, 1993–2009

    Science.gov (United States)

    Williams, Jill; Ibisomi, Latifat; Sartorius, Benn; Kahn, Kathleen; Collinson, Mark; Tollman, Stephen; Garenne, Michel

    2013-01-01

    Background Although there are significant numbers of people displaced by war in Africa, very little is known about long-term changes in the fertility of refugees. Refugees of the Mozambican civil war (1977–1992) settled in many neighbouring countries, including South Africa. A large number of Mozambican refugees settled within the Agincourt sub-district, underpinned by a Health and Socio-demographic Surveillance Site (AHDSS), established in 1992, and have remained there. The AHDSS data provide a unique opportunity to study changes in fertility over time and the role that the fertility of self-settled refugee populations plays in the overall fertility level of the host community, a highly relevant factor in many areas of sub-Saharan Africa. Objectives To examine the change in fertility of former Mozambican self-settled refugees over a period of 16 years and to compare the overall fertility and fertility patterns of Mozambicans to host South Africans. Methods Prospective data from the AHDSS on births from 1993 to 2009 were used to compare fertility trends and patterns and to examine socio-economic factors that may be associated with fertility change. Results There has been a sharp decline in fertility in the Mozambican population and convergence in fertility patterns of Mozambican and local South African women. The convergence of fertility patterns coincides with a convergence in other socio-economic factors. Conclusion The fertility of Mozambicans has decreased significantly and Mozambicans are adopting the childbearing patterns of South African women. The decline in Mozambican fertility has occurred alongside socio-economic gains. There remains, however, high unemployment and endemic poverty in the area and fertility is not likely to decrease further without increased delivery of family planning to adolescents and increased education and job opportunities for women. PMID:23364078

  2. The effects of manure and nitrogen fertilizer applications on soil organic carbon and nitrogen in a high-input cropping system.

    Science.gov (United States)

    Ren, Tao; Wang, Jingguo; Chen, Qing; Zhang, Fusuo; Lu, Shuchang

    2014-01-01

    With the goal of improving N fertilizer management to maximize soil organic carbon (SOC) storage and minimize N losses in high-intensity cropping system, a 6-years greenhouse vegetable experiment was conducted from 2004 to 2010 in Shouguang, northern China. Treatment tested the effects of organic manure and N fertilizer on SOC, total N (TN) pool and annual apparent N losses. The results demonstrated that SOC and TN concentrations in the 0-10cm soil layer decreased significantly without organic manure and mineral N applications, primarily because of the decomposition of stable C. Increasing C inputs through wheat straw and chicken manure incorporation couldn't increase SOC pools over the 4 year duration of the experiment. In contrast to the organic manure treatment, the SOC and TN pools were not increased with the combination of organic manure and N fertilizer. However, the soil labile carbon fractions increased significantly when both chicken manure and N fertilizer were applied together. Additionally, lower optimized N fertilizer inputs did not decrease SOC and TN accumulation compared with conventional N applications. Despite the annual apparent N losses for the optimized N treatment were significantly lower than that for the conventional N treatment, the unchanged SOC over the past 6 years might limit N storage in the soil and more surplus N were lost to the environment. Consequently, optimized N fertilizer inputs according to root-zone N management did not influence the accumulation of SOC and TN in soil; but beneficial in reducing apparent N losses. N fertilizer management in a greenhouse cropping system should not only identify how to reduce N fertilizer input but should also be more attentive to improving soil fertility with better management of organic manure.

  3. Segregation for fertility and meiotic stability in novel Brassica allohexaploids.

    Science.gov (United States)

    Mwathi, Margaret W; Gupta, Mehak; Atri, Chaya; Banga, Surinder S; Batley, Jacqueline; Mason, Annaliese S

    2017-04-01

    Allohexaploid Brassica populations reveal ongoing segregation for fertility, while genotype influences fertility and meiotic stability. Creation of a new Brassica allohexaploid species is of interest for the development of a crop type with increased heterosis and adaptability. At present, no naturally occurring, meiotically stable Brassica allohexaploid exists, with little data available on chromosome behaviour and meiotic control in allohexaploid germplasm. In this study, 100 plants from the cross B. carinata × B. rapa (A2 allohexaploid population) and 69 plants from the cross (B. napus × B. carinata) × B. juncea (H2 allohexaploid population) were assessed for fertility and meiotic behaviour. Estimated pollen viability, self-pollinated seed set, number of seeds on the main shoot, number of pods on the main shoot, seeds per ten pods and plant height were measured for both the A2 and H2 populations and for a set of reference control cultivars. The H2 population had high segregation for pollen viability and meiotic stability, while the A2 population was characterised by low pollen fertility and a high level of chromosome loss. Both populations were taller, but had lower average fertility trait values than the control cultivar samples. The study also characterises fertility and meiotic chromosome behaviour in genotypes and progeny sets in heterozygous allotetraploid Brassica derived lines, and indicates that genotypes of the parents and H1 hybrids are affecting chromosome pairing and fertility phenotypes in the H2 population. The identification and characterisation of factors influencing stability in novel allohexaploid Brassica populations will assist in the development of this as a new crop species for food and agricultural benefit.

  4. Biogas final digestive byproduct applied to croplands as fertilizer contains high levels of steroid hormones.

    Science.gov (United States)

    Rodriguez-Navas, Carlos; Björklund, Erland; Halling-Sørensen, Bent; Hansen, Martin

    2013-09-01

    In this study we evaluate and demonstrate the occurrence of nine natural and one synthetic steroid hormone, including estrogens, androgens and progestagens in biogas final digestate byproduct (digestion liquid) commonly used as an agricultural fertilizer. We investigated two biogas sites that utilize different anaerobic digestion technologies (mesophilic and thermophilic) from swine manure and other organic wastes. Individual hormone concentration levels were observed up to 1478 ng g(-1) dry weight or 22.5 mg kg(-1) N with estrone and progesterone reaching highest concentration levels. Evaluation of the potential environmental burden through the application in agriculture was also assessed on the basis of predicted environmental concentrations. This study indicates that the biogas digestion process does not completely remove steroid hormones from livestock manure and use of final digestate byproduct on croplands contributes to the environmental emission of hormones. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Inoculation Effect of N2-Fixer and P-Solubilizer into a Mixture of Fresh Manure and Phosphate Rock Formulated as Organonitrofos Fertilizer on Bacterial and Fungal Populations

    Directory of Open Access Journals (Sweden)

    Sutopo Ghani Nugroho

    2013-03-01

    Full Text Available Microbial N2-fixer and P-solubilizer were innoculated in a mixture of fresh manure and phosphate rock formulated as an Organonitrophos fertilizer. The population dynamics of bacteria and fungi growing during the composting process were observed. The inoculation treatments consisted of: K = mixture of 20% phosphate rock and 80% of fresh manure + decomposers (control, N = mixture of 20% phosphate rock and 80% of fresh manure + decomposers + N2-fixer (Azotobacter and Azospirillum sp. , P = mixture of 20% phosphate rock and 80% of fresh manure + decomposers + P-solubilizer (A. niger and P. fluorescens, and NP = mixture of 20% phosphate rock and 80% of fresh manure + decomposers + N2-fixer + P-solubilizer. The results showed that inoculation of microbial N2-fixer and combination inoculation of N2-fixer and P-solubilizer increased the total bacterial population compared to that of the control as well as the only inoculation of microbial P-solubilizer on the 14th day of observation in which the bacteria reached the highest population. On all the observation days, the population of fungi in the inoculation of microbial P-solubilizer treatment increased significantly compared to that of the control. However, there was no difference between the populations of fungi in the inoculation of N2-fixer and combination inoculation of N2-fixer and Psolubilizer. The genus of fungy identified in the compost of the mixture of fresh manure and phosphate rock were Chytridium sp., Aspergillus sp., Rhizopus sp., and Fusarium sp.

  6. Modelling strategic interventions in a population with a total fertility rate of 8.3: a cross-sectional study of Idjwi Island, DRC

    Directory of Open Access Journals (Sweden)

    Thomson Dana R

    2012-11-01

    Full Text Available Abstract Background Idjwi, an island of approximately 220,000 people, is located in eastern DRC and functions semi-autonomously under the governance of two kings (mwamis. At more than 8 live births per woman, Idjwi has one of the highest total fertility rates (TFRs in the world. Rapid population growth has led to widespread environmental degradation and food insecurity. Meanwhile family planning services are largely unavailable. Methods At the invitation of local leaders, we conducted a representative survey of 2,078 households in accordance with MEASURE DHS protocols, and performed ethnographic interviews and focus groups with key informants and vulnerable subpopulations. Modelling proximate determinates of fertility, we evaluated how the introduction of contraceptives and/or extended periods of breastfeeding could reduce the TFR. Results Over half of all women reported an unmet need for spacing or limiting births, and nearly 70% named a specific modern method of contraception they would prefer to use; pills (25.4% and injectables (26.5% were most desired. We predicted that an increased length of breastfeeding (from 10 to 21 months or an increase in contraceptive prevalence (from 1% to 30%, or a combination of both could reduce TFR on Idjwi to 6, the average desired number of children. Increasing contraceptive prevalence to 15% could reduce unmet need for contraception by 8%. Conclusions To meet women’s need and desire for fertility control, we recommend adding family planning services at health centers with NGO support, pursuing a community health worker program, promoting extended breastfeeding, and implementing programs to end sexual- and gender-based violence toward women.

  7. Prediction of bull fertility.

    Science.gov (United States)

    Utt, Matthew D

    2016-06-01

    Prediction of male fertility is an often sought-after endeavor for many species of domestic animals. This review will primarily focus on providing some examples of dependent and independent variables to stimulate thought about the approach and methodology of identifying the most appropriate of those variables to predict bull (bovine) fertility. Although the list of variables will continue to grow with advancements in science, the principles behind making predictions will likely not change significantly. The basic principle of prediction requires identifying a dependent variable that is an estimate of fertility and an independent variable or variables that may be useful in predicting the fertility estimate. Fertility estimates vary in which parts of the process leading to conception that they infer about and the amount of variation that influences the estimate and the uncertainty thereof. The list of potential independent variables can be divided into competence of sperm based on their performance in bioassays or direct measurement of sperm attributes. A good prediction will use a sample population of bulls that is representative of the population to which an inference will be made. Both dependent and independent variables should have a dynamic range in their values. Careful selection of independent variables includes reasonable measurement repeatability and minimal correlation among variables. Proper estimation and having an appreciation of the degree of uncertainty of dependent and independent variables are crucial for using predictions to make decisions regarding bull fertility. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Reproductive factors of ovarian and endometrial cancer risk in a high fertility population in Mexico.

    Science.gov (United States)

    Salazar-Martinez, E; Lazcano-Ponce, E C; Gonzalez Lira-Lira, G; Escudero-De los Rios, P; Salmeron-Castro, J; Hernandez-Avila, M

    1999-08-01

    A case-control study was carried out in Mexico City during 1995-1997 among women with epithelial ovarian cancer (84 cases) and endometrial cancer (85 cases). The control group consisted of 668 healthy women, matched according to age categories. In a multivariate analysis, the reproductive risk factors for ovarian and endometrial cancer are similar. The risk of ovarian cancer was inversely related to the number of full-term pregnancies; the odds ratio (OR) was 0.17 and the 95% confidence interval (CI) was 0.05-0.54 when comparing nulliparous women versus those with more than seven pregnancies. For endometrial cancer, a similar association was observed (OR, 0.11; 95% CI, 0.04-0.34). The use of oral contraceptive hormones was inversely associated with both ovarian (OR, 0.36; 95% CI, 0.15-0.83) and endometrial cancer risk (OR, 0.36; 95% CI, 0.14-0.90). In women with a history of more than 8.7 years without ovulation, the risk of ovarian cancer decreased four times (OR, 0.23; 95% CI, 0.10-0.50), and that of endometrial cancer decreased more than five times (OR, 0.17; 95% CI, 0.08-0.35). These two neoplasms are clearly typified as hormone dependent, and it is possible to establish that "ovulation" and "exfoliative" mechanisms jointly determine the level of risk for both ovarian and endometrial cancer.

  9. Iron fertilization and the structure of planktonic communities in high nutrient regions of the Southern Ocean

    Science.gov (United States)

    Quéguiner, Bernard

    2013-06-01

    In this review article, plankton community structure observations are analyzed both for artificial iron fertilization experiments and also for experiments dedicated to the study of naturally iron-fertilized systems in the Atlantic, Indian and Pacific sectors of the Southern Ocean in the POOZ (Permanently Open Ocean Zone) and the PFZ (Polar Frontal Zone). Observations made in natural systems are combined with those from artificially perturbed systems, in order to evaluate the seasonal evolution of pelagic communities, taking into account controlling factors related to the life cycles and the ecophysiology of dominant organisms. The analysis considers several types of planktonic communities, including both autotrophs and heterotrophs. These communities are spatially segregated owing to different life strategies. A conceptual general scheme is proposed to account for these observations and their variability, regardless of experiment type. Diatoms can be separated into 2 groups: Group 1 has slightly silicified fast growing cells that are homogeneously distributed in the surface mixed layer, and Group 2 has strongly silicified slowly growing cells within discrete layers. During the growth season, Group 1 diatoms show a typical seasonal succession of dominant species, within time windows of development that are conditioned by physical factors (light and temperature) as well as endogenous specific rhythms (internal clock), and biomass accumulation is controlled by the availability of nutrients. Group 1 diatoms are not directly grazed by mesozooplankton which is fed by protozooplankton, linking the microbial food web to higher trophic levels. Instead, successive dominant species of Group 1 are degraded via bacterial activity at the end of their growth season. Organic detritus fragments feed protozooplankton and mesozooplankton. The effective silicon pump leads to the progressive disappearance of silicic acid in surface waters. In contrast, Group 2 is resistant to grazing

  10. Is glycosylated haemoglobin a marker of fertility?

    DEFF Research Database (Denmark)

    Hjollund, N H; Jensen, T K; Bonde, J P

    1999-01-01

    We performed a follow-up study of time to pregnancy in a population of first-time pregnancy planners without previous reproductive experience. The objective of this paper is to report and discuss a finding of a strong relationship between glycosylated haemoglobin (HbA1C) and fertility. A total...... concentration of inhibin A. No association was found between HbA1C and psychosocial distress. The reduced fertility among women with high HbA1C may be due to an association with subclinical polycystic ovaries as indicated by the hormonal profile....

  11. Infertility, medical advice and treatment with fertility hormones and/or in vitro fertilisation: a population perspective from the Australian Longitudinal Study on Women's Health.

    Science.gov (United States)

    Herbert, Danielle L; Lucke, Jayne C; Dobson, Annette J

    2009-08-01

    To identify the factors associated with infertility, seeking advice and treatment with fertility hormones and/or in vitro fertilisation (IVF) among a general population of women. Participants in the Australian Longitudinal Study on Women's Health aged 28-33 years in 2006 had completed up to four mailed surveys over 10 years (n=9,145). Parsimonious multivariate logistic regression was used to identify the socio-demographic, biological (including reproductive histories), and behavioural factors associated with infertility, advice and hormonal/IVF treatment. For women who had tried to conceive or had been pregnant (n=5,936), 17% reported infertility. Among women with infertility (n=1031), 72% (n=728) sought advice but only 50% (n=356) used hormonal/IVF treatment. Women had higher odds of infertility when: they had never been pregnant (OR=7.2, 95% CI 5.6-9.1) or had a history of miscarriage (OR range=1.5-4.0) than those who had given birth (and never had a miscarriage or termination). Only one-third of women with infertility used hormonal and/or IVF treatment. Women with PCOS or endometriosis were the most proactive in having sought advice and used hormonal/IVF treatment. Raised awareness of age-related declining fertility is important for partnered women aged approximately 30 years to encourage pregnancy during their prime reproductive years and reduce the risk of infertility.

  12. Generation of highly potent organic fertilizer from pernicious aquatic weed Salvinia molesta.

    Science.gov (United States)

    Hussain, Naseer; Abbasi, Tasneem; Abbasi, Shahid Abbas

    2017-12-05

    Utilization of Salvinia molesta, an aquatic weed which is notorious for its allelopathy and invasiveness, has been explored by its vermicomposting. Fourier transform infrared spectroscopy (FT-IR) and plant bioassay tests were conducted to analyze the composition and fertilizer value of S .molesta vermicompost. Germination and seedling growth tests were performed in soil supplemented with vermicompost at levels ranging from 0.75 to 40% by weight of the soil on three common food plants, ladies finger (Abelmoschus esculentus), cucumber (Cucumis sativus), and green gram (Vigna radiata). The influence of S. molesta's vermicompost on some of the physicochemical and biological attributes of the soil was also studied. FT-IR analysis revealed that S. molesta loses its allelopathy, as the chemical compounds that are responsible for it are largely destroyed, in the course of its vermicomposting. There is also an indication that a portion of lignin content of S. molesta is degraded. Vermicompost enhanced the germination success and promoted the morphological growth and biochemical content of the plant species studied. It also bestowed plant friendly physicochemical and biological attributes to the soil. The findings raise the prospect that billions of tons of S. molesta biomass-which not only goes to waste at present but is also a cause of serious harm to the environment-may become utilizable in organic agriculture.

  13. Lack of replication of four candidate SNPs implicated in human male fertility traits: a large-scale population-based study.

    Science.gov (United States)

    Sato, Youichi; Tajima, Atsushi; Tsunematsu, Kouki; Nozawa, Shiari; Yoshiike, Miki; Koh, Eitetsue; Kanaya, Jiro; Namiki, Mikio; Matsumiya, Kiyomi; Tsujimura, Akira; Komatsu, Kiyoshi; Itoh, Naoki; Eguchi, Jiro; Imoto, Issei; Yamauchi, Aiko; Iwamoto, Teruaki

    2015-06-01

    Are the four candidate loci (rs7867029, rs12870438, rs7174015 and rs724078) for human male fertility traits, identified in a genome-wide association study (GWAS) of a Hutterite population in the USA, associated with semen quality traits in a Japanese population? The four single nucleotide polymorphisms (SNPs) rs7867029, rs12870438, rs7174015 and rs724078 have no association with semen parameters in a meta-analysis of two Japanese male cohorts. Four (rs7867029, rs12870438, rs7174015 and rs724078) of the SNPs associated with family size or birth rate in the GWAS of a Hutterite population in the USA were associated with semen parameters in ethnically diverse men from Chicago, USA. This is a replication study in a total of 2015 Japanese subjects, including 791 fertile men and 1224 young men from the general population. We performed a replication study in two cohorts to assess whether the SNPs rs7867029, rs12870438, rs7174015 and rs724078 are associated with sperm concentration, semen volume, total sperm numbers, total motile sperm numbers or sperm motility. The rs12870438 SNP was detected by restriction fragment length polymorphism PCR while rs7174015, rs724078 and rs7867029 SNPs were genotyped using TaqMan probes. This study indicated that none of the four SNPs rs7867029, rs12870438, rs7174015 and rs724078 displayed a significant association with semen parameters in the meta-analysis of two Japanese male cohorts. Only four SNPs identified in the Hutterite GWAS were examined for associations with semen quality traits in a Japanese population. In addition, the linkage disequilibrium structures around the testing markers were different between ethnic groups. Locus mapping studies using a set of tagging SNPs across the loci will be necessary in populations with larger sample sizes in order to understand the contribution of specific genes to semen quality. This study was supported in part by the Ministry of Health and Welfare of Japan (1013201) (to T.I.), Grant-in-Aids for

  14. Fertility and Birth Rates: Indicators of Child and Youth Well-Being. Updated. October 2016

    Science.gov (United States)

    Child Trends, 2016

    2016-01-01

    Tracking trends in fertility and birth rates is essential in planning for the current and future needs of multiple generations. Sustained high fertility rates lead to disproportionately large populations of young dependents, driving demand for supports for young families, for additional schools, and for affordable child care. For example, during…

  15. The Role of socioeconomic factors in fertility of Umuahia women in ...

    African Journals Online (AJOL)

    Rapid population growth arising from high fertility has been argued as being disadvantageous to the economic growth of countries especially the developing country like Nigeria. This paper examines the role of socioeconomic factors in fertility. The study elicited information from 500 women of the reproductive age of 15-49 ...

  16. Resposta de cafezais adensados à adubação NPK NPK fertilization for high tree density coffee plantations

    Directory of Open Access Journals (Sweden)

    PAULO BOLLER GALLO

    1999-01-01

    Full Text Available A adubação NPK para cafezais adensados, em doses por área, tem sido superestimada por derivar da recomendação para cafezais tradicionais, que é calculada por planta. O objetivo deste trabalho é avaliar o efeito da adubação NPK em dois cafezais adensados: um com a variedade Mundo Novo e outro com a ‘Catuaí’, em condições de produção comercial. Instalaram-se dois experimentos fatoriais, com delineamento fatorial fracionado 1/2 (4 x 4 x 4, na Fazenda Santo Antônio e na Samambaia, no município de Mococa (SP, em cafezais em plena produção. Na Santo Antônio, o ‘Mundo Novo’, em produção, tinha um espaçamento de 2,0 x 1,0 m e, na Samambaia, o ‘Catuaí’ tinha um espaçamento de 1,5 x 1,0 m. As doses de nutrientes aplicadas foram as seguintes: nitrogênio: 100, 200, 300 e 400 kg.ha-1 de N, como uréia; fósforo: 0, 30, 60 e 90 kg. ha-1 de P2O5; na forma de superfosfato triplo e potássio: 0, 80, 160 e 240 kg. ha-1 de K2O, na forma de cloreto de potássio. As adubações iniciaram-se em 1989, sendo obtidas, de 1991 a 1994, quatro colheitas em cada local. No experimento da Fazenda Santo Antônio, onde houve efeito estatisticamente depressivo de N, devem ser ressal-tados o teor médio de fósforo e o alto de potássio no solo, na amostragem inicial, e o teor elevado de N nas folhas, nas amostragens de 1992 e 1993. No experimento da Fazenda Samambaia, destaca-se o efeito significativo da adubação fosfatada sobre a produção do cafeeiro. Os resultados permitem concluir que a adubação nitrogenada em cafeeiro, em sistema adensado, poderá reduzir a produção quando há excesso de sombreamento; o teor de N total nas folhas e a análise de solo para P e K mostraram-se como ferramentas eficientes na avaliação da disponibilidade desses nutrientes e na resposta à adubação.The NPK fertilization for high tree density coffee plantations, on an area basis, has been overestimated because it is derived from the recommendation for the

  17. Natural fertility in the Philippines.

    Science.gov (United States)

    Aquino, E G

    1982-01-01

    The hypothesis that modernization trends in the Philippines led to an increase in fecundity and natural fertility between 1953-1972 was tested, using data from the 1973 National Demographic Survey. More specifically, it was hypothesized that increases in education, income levels, urbanization, female labor force participation, and other factors exerted a positive influence on the population's health and nutritional status and increased the risk of pregnancy by diminishing the strength of sexual taboos and by decreasing the incidence of breastfeeding. These changes, in turn, had a positive impact on natural fertility. Natural fertility was defined as marital fertility in the absence of specific efforts to control fertility. The use of natural fertility instead of fecundity allowed for the influence of behavioral patterns, such as breastfeeding and sexual taboos, on fertility. Period analysis of age specific marital fertility rates for each 5 year period between 1953-72 and cohort analysis of age specific marital fertility rates for the birth cohorts, aged 55-59, 50-54, 45-49, 40-44, and 35-39 in 1973 were undertaken. The effect of fertility control was determined by using an index derived from an equation provided by Coale and Trussell. Findings of both the period and cohort analysis supported the hypothesis. Period analysis revealed that natural fertility increased between 1953-57 and 1969-72 by 10% and that the greatest increase occurred during the 1950s when Philippine society experienced major modernization changes. The increases in natural fertility were accompanied by corresponding increases in fertility regulation in each time period. These trends tended to cancel each other out and resulted in a relatively stable total marital fertility rate throughout the time period. Cohort analysis revealed that only the total marital fertility rate of the youngest cohort was influenced by fertility regulation. The level of natural fertility for all cohorts as a group

  18. Progress report 1993 : Regulation of mule deer population growth by fertility control : Laboratory, field, and simulation experiments

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We developed analytical models to describe dynamics of the Rocky Mountain Arsenal mule population. Our objectives were: 1) To estimate carrying capacity of the...

  19. Women with celiac disease present with fertility problems no more often than women in the general population

    OpenAIRE

    Dhalwani, Nafeesa N.; West, Joe; Sultan, Alyshah Abdul; Ban, Lu; Tata, Laila J.

    2014-01-01

    BACKGROUND & AIMS: Studies have associated infertility with celiac disease. However, these included small numbers of women attending infertility specialist services and subsequently screened for celiac disease, and therefore may not have been representative of the general population. We performed a large population-based study of infertility and celiac disease in women from the United Kingdom. \\ud \\ud METHODS: We identified 2,426,225 women with prospective UK primary care records between 1990...

  20. Fertility reduction programmes should accompany land reforms.

    Science.gov (United States)

    Atiku, J

    1994-01-01

    Changes in population size both affect and are affected by the rate of development. With the total world population estimated to be 5.7 billion in mid-1994 and annual growth at 1.7%, declines in total fertility rates and overall growth rates in developing countries have not been sufficient to precipitate a decline in actual numbers. The population of developing countries has doubled from 1962 to 1994. The highest growth rates are expected to be in sub-Saharan Africa, but the largest absolute increase in population is expected to occur in Asia. Uganda's population has increased from 4.9 to 16.7 million from 1948 to 1991. At the current rate of increase (2.5%) and taking AIDS into account, Uganda's population is expected to double in 28 years. Rapid population growth in developing countries can be explained by the following factors: 1) high levels of morbidity and mortality which threaten child survival and encourage large families; 2) early marriage which extends reproductive activity; 3) a high value placed on children, especially sons; 4) unmet needs for family planning; 5) widespread poverty which causes children to be viewed as old age security; and 6) population momentum which would contribute to growth even if replacement fertility were achieved because of the current age-sex structure of the population. The impact of rapid population growth on development requires further study, but some things are clear. Economic development is hindered when the number of dependent and poor individuals in a population increases. High rates of fertility result in poor infant and maternal health. The provision of social welfare services and the capacity for providing basic services such as health care, education, safe water, and sanitation is strained by rapid population growth. Also, the quality of the environment is adversely affected by rapid population growth. Population policies should be developed for each country and should emphasize activities to improve individual

  1. Fertility of Czech Females Could Be Lower than Expected: Trends in Future Development of Age-Specific Fertility Rates up to the Year 2050

    Directory of Open Access Journals (Sweden)

    Ondřej Šimpach

    2015-03-01

    Full Text Available Fertility is an essential aspect of reproduction or population replacement of each country. The challenge for demographers is to model fertility and also to estimate its potential future level for the purposes of population projections. In the case of the Czech Republic we have the population projections provided by the Czech Statistical Office (CZSO with overlooking of the total fertility rate in low, medium and high variant. These estimates despite being based on expert judgments, seem to be too positive compared to the past development of the time series of age-specific fertility rates. The aim of this paper is to assess the situation of fertility in the Czech Republic, to analyse the past development of the time series of age-specific fertility rates using one-dimensional Box-Jenkins models and multidimensional stochastic Lee-Carter approach. Together with found trend in time series and principal components estimated by Lee-Carter’s model a forecasts of age-specific fertility rates up to the year 2050 is constructed. Th ese rates are lower than those provided by CZSO in its three variants of the Czech Republic’s population projection, and therefore we discuss the causes at the end of the paper. We would like to point out that the potential future development of Czech females fertility could be lower than which are currently expected.

  2. A high-resolution linkage map of the Rfd1, a restorer-of-fertility locus for cytoplasmic male sterility in radish (Raphanus sativus L.) produced by a combination of bulked segregant analysis and RNA-Seq.

    Science.gov (United States)

    Lee, Young-Pyo; Cho, Youngcho; Kim, Sunggil

    2014-10-01

    We utilized a combination of BSA and RNA-Seq to identify SNPs linked to the Rfd1 locus, a restorer-of-fertility gene in radish. A high-density linkage map was constructed using this approach. Male fertility of cytoplasmic male sterility conditioned by the Dongbu cytoplasmic and genic male-sterility cytoplasm can be restored by a restorer-of-fertility locus, Rfd1, in radish. To construct a high-density linkage map and to identify a candidate gene for the Rfd1 locus, bulked segregant analysis and RNA-seq approaches were combined. A total of 26 and 28 million reads produced from male-fertile and male-sterile bulked RNA were mapped to the radish reference unigenes. After stringent screening of SNPs, 327 reliable SNPs of 109 unigenes were selected. Arabidopsis homologs for 101 of the 109 genes were clustered around the 4,000 kb region of Arabidopsis chromosome 3, which was syntenic to the Rfd1 flanking region. Since the reference unigene set was incomplete, the contigs were de novo assembled to identify 134 contigs harboring SNPs. Most of SNP-containing contigs were also clustered on the same syntenic region in Arabidopsis chromosome. A total of 21 molecular markers positioned within a 2.1 cM interval including the Rfd1 locus were developed, based on the selected unigenes and contigs. A segregating population consisting of 10,459 individuals was analyzed to identify recombinants containing crossovers within this interval. A total of 284 identified recombinants were then used to construct a high-density map, which delimited the Rfd1 locus into an 83-kb syntenic interval of Arabidopsis chromosome 3. Since no candidate gene, such as a pentatricopeptide repeat (PPR)-coding gene, was found in this interval, 231 unigenes and 491 contigs containing putative PPR motifs were analyzed further, but no PPR gene in linkage disequilibrium with the Rfd1 locus could be found.

  3. Marriage and fertility in the developed countries.

    Science.gov (United States)

    Westoff, C F

    1978-12-01

    Most developed countries have reached zero population growth or less and, while population projections have often proved badly off-target, it seems that currently low fertility levels are the result of a long-term trend, which was interrupted in the last 100 years only by the still-unexplained postwar baby boom, and which will probably continue. The declining trend has accompanied economic development and modernization, which have transformed the economic value of children, making them a drain on resources rather than a source of income. The concomitant social changes seem largely irreversible: urban economy, the decline in traditional authority, universal, prolonged education, equality of women, low infant mortality, high consumer demands and sophisticated birth control technology are all here to stay. The theory that fertility exhibits a cyclical pattern based on people's perception of their degree of economic and social opportunity ignores the other elements affecting fertility behavior, especially the radical change in the status and expectations of women. Several trends in marriage and reproductive behavior in the U.S., Denmark and Sweden reinforce the presumption that fertility will remain low: declining number of marriages; postponement of marriage; increased tendency for unmarried couples to live together; instability of marriage shown by high divorce rates and declining remarriage rates; and increasing economic activity by women. The traditional institution of marriage is losing its economic, sexual, sociological and parenting rationales. Thus, declining fertility is both cause and consequence of changes in marriage. In Europe, where the decline is more advanced than in the U.S., governments are concerned that population growth will be too low and have instituted social welfare measures to induce and facilitate childbearing and childrearing. As women become more career-oriented, greater incentives will have to be provided. Manipulating immigration quotas

  4. Modeling fertility curves in Africa

    Directory of Open Access Journals (Sweden)

    Ezra Gayawan

    2010-02-01

    Full Text Available The modeling of fertility patterns is an essential method researchers use to understand world-wide population patterns. Various types of fertility models have been reported in the literature to capture the patterns specific to developed countries. While much effort has been put into reducing fertility rates in Africa, models which describe the fertility patterns have not been adequately described. This article presents a flexible parametric model that can adequately capture the varying patterns of the age-specific fertility curves of African countries. The model has parameters that are interpretable in terms of demographic indices. The performance of this model was compared with other commonly used models and Akaike's Information Criterion was used for selecting the model with best fit. The presented model was able to reproduce the empirical fertility data of 11 out of 15 countries better than the other models considered.

  5. [Fertility decline in China and family planning programs].

    Science.gov (United States)

    Notkola, V; Nieminen, M

    1995-01-01

    "The article looks in detail at the population development in China since the 1950s, highlighting some dramatic changes. In the late 1950s the country was hit by widespread famine, which resulted in increased mortality and decreased fertility. Infant mortality climbed to almost 300/1,000. During the 1960s fertility began to increase again and mortality declined. From the beginning of the 1970s fertility started to decline, dropping from about six to just over two children per woman in the late 1980s. Today, fertility is thought to be below replacement level. The main reason for this fertility decline lies in the highly efficient family planning programmes implemented in China since the 1950s and particularly since the 1970s. The decline in infant mortality and the favourable socio-economic development have also been important factors in the decline in fertility. Although fertility in China is currently at a low level, the country's population is still set to grow." (SUMMARY IN ENG) excerpt

  6. Fertilization of SRC Willow, I

    DEFF Research Database (Denmark)

    Sevel, L.; Nord-Larsen, Thomas; Ingerslev, Morten

    2014-01-01

    of nitrogen, and that similar biomass production response can be achieved by use of mineral fertilizer, sewage sludge and animal manure. A 2-year experiment was established with the clone Tordis grown on a sandy soil in northern Jutland, Denmark. The experiment included mineral fertilizer, sludge and manure......, and treatments of different doses up to 360 kg nitrogen ha. The fertilization led to a modest but significant increase in biomass production. The largest production of 11.9 oven dried tons/ha/year was obtained for the application of 60 kg nitrogen ha annually. Higher doses did not lead to increased biomass...... production; in fact, production seemed to decline with increasing fertilization application (not significant). We found no difference in production between different types of fertilizers. The limited response of the fertilization may be caused by a high fertility of the soil due to former agricultural...

  7. Relationship between the pre- and postpartum body condition scores and periparturient indices and fertility in high-yielding dairy cows

    Directory of Open Access Journals (Sweden)

    Stefańska Barbara

    2016-03-01

    Full Text Available Introduction: The aim of this study was to investigate the relationship between body condition score (BCS determined on the dry-off day, calving day, and in the first month of lactation, its changes during the dry period and early lactation, and periparturient indices and fertility in high-producing dairy cows. Material and Methods: The experiment was conducted in two herds: A and B, located in Western Poland. The studies were conducted on 116 and 108 Polish Holstein-Friesian dairy cows respectively, with an average milk yield of >10 000 kg/305-day lactation. The experiment included the dry period (-56 d to the calving day, the calving day, and early lactation (from +1 to +56 d. The experimental factor was BCS (0 to 5-point scale. The BCS was performed by one person on day -56, on parturition day (in the first 12 h after calving and on day 30 of lactation. Results: A decrease in BCS (≥-0.25 in herd A during the dry period accelerated the planned calving period by 7.3 d. In the group of cows with BCS 3.50 in the first month of lactation (30 d resulted in the extension of uterine involution period (56 d. Improvement of BCS during the dry period shortened the anoestrus (60 d in herd A and the period of insemination service (60 d in herd B. However, in this group (IM BCS ≥ 0.25 of cows the day of the highest artificial insemination index (2.50 in herd B was analysed. Conclusion: The body condition on the dry-off day and at calving, as well as its deterioration in the first month of lactation, have a considerable effect on fertility indices in dairy cows, thus confirming the advisability of its regular monitoring during routine operations connected with the management of a dairy cattle herd.

  8. Cross-Breeding Is Inevitable to Conserve the Highly Inbred Population of Puffin Hunter: The Norwegian Lundehund.

    Science.gov (United States)

    Kettunen, Anne; Daverdin, Marc; Helfjord, Turid; Berg, Peer

    2017-01-01

    The Norwegian Lundehund is a highly endangered native dog breed. Low fertility and high frequency predisposition to intestinal disorder imply inbreeding depression. We assessed the genetic diversity of the Lundehund population from pedigree data and evaluated the potential of optimal contribution selection and cross-breeding in the long-term management of the Lundehund population. The current Norwegian Lundehund population is highly inbred and has lost 38.8% of the genetic diversity in the base population. Effective population size estimates varied between 13 and 82 depending on the method used. Optimal contribution selection alone facilitates no improvement in the current situation in the Lundehund due to the extremely high relatedness of the whole population. Addition of (replacement with) 10 breeding candidates of foreign breed to 30 Lundehund breeders reduced the parental additive genetic relationship by 40-42% (48-53%). Immediate actions are needed to increase the genetic diversity in the current Lundehund population. The only option to secure the conservation of this rare breed is to introduce individuals from foreign breeds as breeding candidates.

  9. Cross-Breeding Is Inevitable to Conserve the Highly Inbred Population of Puffin Hunter: The Norwegian Lundehund.

    Directory of Open Access Journals (Sweden)

    Anne Kettunen

    Full Text Available The Norwegian Lundehund is a highly endangered native dog breed. Low fertility and high frequency predisposition to intestinal disorder imply inbreeding depression. We assessed the genetic diversity of the Lundehund population from pedigree data and evaluated the potential of optimal contribution selection and cross-breeding in the long-term management of the Lundehund population. The current Norwegian Lundehund population is highly inbred and has lost 38.8% of the genetic diversity in the base population. Effective population size estimates varied between 13 and 82 depending on the method used. Optimal contribution selection alone facilitates no improvement in the current situation in the Lundehund due to the extremely high relatedness of the whole population. Addition of (replacement with 10 breeding candidates of foreign breed to 30 Lundehund breeders reduced the parental additive genetic relationship by 40-42% (48-53%. Immediate actions are needed to increase the genetic diversity in the current Lundehund population. The only option to secure the conservation of this rare breed is to introduce individuals from foreign breeds as breeding candidates.

  10. In Vitro Fertilization in Women With Inflammatory Bowel Disease Is as Successful as in Women From the General Infertility Population.

    Science.gov (United States)

    Oza, Sveta Shah; Pabby, Vikas; Dodge, Laura E; Moragianni, Vasiliki A; Hacker, Michele R; Fox, Janis H; Correia, Katharine; Missmer, Stacey A; Ibrahim, Yetunde; Penzias, Alan S; Burakoff, Robert; Friedman, Sonia; Cheifetz, Adam S

    2015-09-01

    Inflammatory bowel disease (IBD) affects women of reproductive age, so there are concerns about its effects on fertility. We investigated the success of in vitro fertilization (IVF) in patients with IBD compared with the general (non-IBD) IVF population. We conducted a matched retrospective cohort study of female patients with IBD who underwent IVF from 1998 through 2011 at 2 tertiary care centers. Patients were matched 4:1 to those without IBD (controls). The primary outcome was the cumulative rate of live births after up to 6 cycles of IVF. Secondary outcomes included the proportion of patients who became pregnant and the rate of live births for each cycle. Forty-nine patients with Crohn's disease (CD), 71 patients with ulcerative colitis (UC), 1 patient with IBD-unclassified, and 470 controls underwent IVF during the study period. The cumulative rate of live births was 53% for controls, 69% for patients with UC (P = .08 compared with controls), and 57% for patients with CD (P = .87 compared with controls). The incidence of pregnancy after the first cycle of IVF was similar among controls (40.9%), patients with UC (49.3%; P = .18), and patients with CD (42.9%; P = .79). Similarly, the incidence of live births after the first cycle of IVF was similar among controls (30.2%), patients with UC (33.8%; P = .54), and patients with CD (30.6%; P = .95). Based on a matched cohort study, infertile women with IBD achieve a rate of live births after IVF that is comparable with those of infertile women without IBD. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

  11. Marriage season, promptness of successful pregnancy and first-born sex ratio in a historical natural fertility population - evidence for sex-dependent early pregnancy loss?

    Science.gov (United States)

    Nonaka, K.; Desjardins, Bertrand; Charbonneau, Hubert; Légaré, Jacques; Miura, Teiji

    We investigated population-based vital records of the seventeenth and eighteenth century French Canadian population to assess the effects of marriage season on the outcome of the first births under natural fertility conditions (n=21,698 marriages). Promptness of the first successful conception after marriage differed according to marriage season; the proportion of marriages with a marriage-first birth interval of 8.0-10.0 months was lowest (34%) for marriages in August-October (P=0.001). Although the male/female sex ratio of the babies born with an interval of 8.0-10.0 months was generally higher (1.10) than those with an interval of 10.0-24.0 months (1.05), the marriages in August-October resulted in a significantly reduced sex ratio (0.96) among only the prompt conceptions (P=0.026). We discuss whether this seasonal reduction of the sex ratio could be partly explained by a clustered pregnancy loss of male zygotes in early pregnancy.

  12. High-sucrose-induced maternal obesity disrupts ovarian function and decreases fertility in Drosophila melanogaster.

    Science.gov (United States)

    Brookheart, Rita T; Swearingen, Alison R; Collins, Christina A; Cline, Laura M; Duncan, Jennifer G

    2017-06-01

    As the obesity epidemic worsens, the prevalence of maternal obesity is expected to rise. Both high-fat and high-sucrose diets are known to promote maternal obesity and several studies have elucidated the molecular influence of high-fat feeding on female reproduction. However, to date, the molecular impact of a high-sucrose diet on maternal obesity remains to be investigated. Using our previously reported Drosophila high-sucrose maternal obesity model, we sought to determine how excess dietary sucrose impacted the ovary. High-sucrose diet (HSD) fed adult females developed systemic insulin resistance and exhibited an ovarian phenotype characterized by excess accumulation of lipids and cholesterol in the ovary, decreased ovary size, and impaired egg maturation. We also observed decreased expression of antioxidant genes and increased protein carbonylation in the ovaries of HSD females. HSD females laid fewer eggs; however, the overall survival of offspring was unchanged relative to lean control females. Ovaries of HSD females had increased mitochondrial DNA copy number and decreased expression of key mitochondrial regulators, suggestive of an ineffective compensatory response to mitochondrial dysfunction. Mitochondrial alterations were also observed in male offspring of obese females. This study demonstrates that high-sucrose-induced maternal obesity promotes insulin resistance, while disrupting ovarian metabolism and function. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Uncertain lifetime, fertility and social security

    OpenAIRE

    Akira Yakita

    2001-01-01

    Investigating the effects of population aging on fertility and economic growth, we show that an increase in life expectancy lowers the fertility rate and raises life-cycle savings, and that a pay-as-you-go social security does not reverse the effect on fertility.

  14. Playing the Fertility Game at Work

    DEFF Research Database (Denmark)

    Ciliberto, Federico; Miller, Amalia Rebecca; Nielsen, Helena Skyt

    2016-01-01

    We study workplace peer effects in fertility decisions using a game theory model of strategic interactions among coworkers that allows for multiple equilibria. Using register-based data on fertile-aged women working in medium sized establishments in Denmark, we uncover negative average peer effects...... work an important consideration, beyond simply if they work, in predicting population fertility....

  15. Recent Demographic Developments in France: Fertility at a More Than 30-Year High

    OpenAIRE

    France Prioux

    2007-01-01

    La France métropolitaine compte 61,5 millions d?habitants au 1er janvier 2007. L?augmentation de la population a été soutenue en 2006 (+ 6,1 ?), du fait de l?augmentation des naissances (+ 2,9 %) et de la diminution des décès (? 1,4 %). Le nombre d?étrangers admis à séjourner a très légèrement diminué en 2005. L?indicateur conjoncturel de fécondité s?élève à 1,98 enfant par femme en 2006 (+ 3,2 %). Malgré tout, la descendance finale diminue entre les générations 1960 et 1970, mais elle ne dev...

  16. The World Fertility Survey: charting global childbearing.

    Science.gov (United States)

    Lightbourne R; Singh, S; Green, C P

    1982-03-01

    Interviewing some 350,000 women in 42 developing countries and 20 developed countries representing nearly 40% of the world's population, the World Fertility Survey (WFS) is in a unique position to document the historic 1970s slowdown in global population growth. This Bulletin describes efforts begun in 1972 to ensure high quality, internationally comparable, accessible data, the data's importance for policymakers, planners and researchers, and major findings available by early 1982 from directly assisted WFS surveys in 29 developing countries and contraceptive use data from WFS-type surveys in 16 developed countries. Marital fertility has declined in all developing regions except Africa but still averages from 4.6 children/woman in Latin America to 6.7 in Africa, while preferred family size ranges from 3.0 children in Turkey to 8.9 in Senegal--far above the average 2.2-2.5 children/woman needed to end developing countries' population growth in the long run. However, women ages 15-19 prefer nearly 2 children fewer than the oldest women ages 45-49; 3.8 vs. 5.7 on the average. Nearly 1/2 (48%) of married women surveyed in 27 countreis said they wanted no more children. Preventing all unwanted births would reduce birth rates up to 15 births/1000 population in these countries. Overall, 32% of married, fecund women in developing countries are using contraception compared to an average 72% in 16 developed countries. Education, literacy, and more available family planning services increase contraceptive use. Age at marriage is rising in Asia, but this factor alone has little effect on fertility. Infant mortality is higher in many developing countries than previously thought. Breastfeeding is an important restraint on fertility in most developing countries but is declining among more educated, employed, and urban women which could raise fertility if not compensated for by gains in contraceptive use.

  17. Modernization and tradition in the recent history of italian fertility.

    Science.gov (United States)

    Bacci, M L

    1967-06-01

    The secular decline of Italian fertility, started in the last decade of the nineteenth century, came to an end in the early 1950'sand has recovered slightly in the last fifteen years. Italian experience seems to follow, with a twenty-year lag, the experience of the more advanced western European populations. At present, with an average of 2.5 children per marriage, Italian fertility is very close to the French and to the average European level.At the regional level, two contrasting patterns can be detected. On one side stands the very low fertility of the North and of the Center, mostly below replacement in the last thirty years;on the other, the still high fertility of the South.In the North and in the Center, where the decline started earlier, fertility has fallen well below replacement level in the last thirty years. In the South, where the decline started in the late 1920's and early 1930's, a large family system still prevails, and the spreading of voluntary control faces barriers setup by a long historyof cultural isolation,attachment to tradition and religion. In the last 15 years, however, the gap has narrowed slowly, more because of an upturn of fertility in the North and in the Center than because of the decline in the South.Another interesting feature of Italian fertility is low class differentials: the fertility of the most prolific segment (farmers, farm laborers) is only 20 percent higher than the fertility of the less prolific professional groups. Finally, Italian experience provides an interesting example of the changing relationship linking the economic level of the population and fertility changes; in 1931-51 a negative correlation linked the changes in fertility to the economic level of the region, while in 1951-61 and 1961-66 a very high and positive correlation can be observed.As for the future trends in fertility, two factors may have an important role. In the first place, on the one hand, the economic policy of the government, aiming at

  18. Reproductive performance primarily depends on the female genotype in a two-factorial breeding experiment using high-fertility mouse lines.

    Science.gov (United States)

    Langhammer, Martina; Michaelis, Marten; Hartmann, Michaela F; Wudy, Stefan A; Sobczak, Alexander; Nürnberg, Gerd; Reinsch, Norbert; Schön, Jennifer; Weitzel, Joachim M

    2017-03-01

    Mouse models showing an improved fertility phenotype are barely described in the literature. In the present study, we further characterized two outbred mouse models that have been selected for the phenotype 'high fertility' for more than 177 generations (fertility lines (FL) 1 and 2). In order to delineate the impact of males and females on fertility parameters, we performed a two-factorial breeding experiment by mating males and females of the three different genotypes (FL1, FL2, unselected control (Ctrl)) in all 9 possible combinations. Reproductive performance, such as number of offspring per litter or total birth weight of the entire pup, mainly depends on the female genotype. Although the reproductive performance of FL1 and FL2 is very similar, their phenotypes differ. FL2 animals of both genders are larger compared to FL1 and control animals. Females of the control line delivered offspring earlier compared to FL1 and FL2 dams. Males of FL1 are the lightest and the only ones who gained weight during the two weeks mating period. To address whether this effect is correlated with differing serum androgen levels, we measured the concentrations of testosterone, dehydroepiandrosterone, 4-androstenedione, androstanediol and dihydrotestosterone in males of all three lines by GC-MS. We measured serum testosterone between 5.0 and 6.4 ng/mL, whereas the concentrations of the other androgens were at least one order of magnitude lower, with no significant differences between the lines. Our data indicate that reproductive outcome largely depends on the genotype of the female in a two-factorial breeding experiment and supports previous findings that the phenotype 'high fertility' is warranted by using different physiological strategies. © 2017 Society for Reproduction and Fertility.

  19. Austria: Persistent low fertility since the mid-1980s

    Directory of Open Access Journals (Sweden)

    Henriette Engelhardt

    2008-07-01

    Full Text Available This chapter offers an in-depth analysis of fertility in Austria, a country which has experienced a low and relatively stable fertility level and a gradual postponement of childbearing since the mid-1980s. We begin by summarising Austrian population trends in the post-World War II period and highlighting recent relatively high migration levels. We outline the long history of sub-replacement fertility and high childlessness in Austria and look in detail at recent parity-specific developments, trends in family size, delayed childbearing and persistent fertility differences by education level, country of origin and religious affiliation. The chapter then summarises main trends in family-related behaviour, including the changing patterns of leaving parental home, the rise in cohabitation, the decline in marriage and the rise of divorce and the diversity in non-marital childbearing, which has a long tradition in many parts of the country. We discuss the development of family policies in Austria and their relationship to fertility during the past decades. Social policies in Austria provide only a limited support for a reconciliation of childrearing and employment among mothers with children below the age of three. A combination of one of the highest family spending rates among the OECD countries and the low fertility rates indicate that structural constraints (such as the availability of childcare constitute part of the explanation of low fertility.

  20. Regime shift in fertilizer commodities indicates more turbulence ahead for food security.

    Science.gov (United States)

    Elser, James J; Elser, Timothy J; Carpenter, Stephen R; Brock, William A

    2014-01-01

    Recent human population increase has been enabled by a massive expansion of global agricultural production. A key component of this "Green Revolution" has been application of inorganic fertilizers to produce and maintain high crop yields. However, the long-term sustainability of these practices is unclear given the eutrophying effects of fertilizer runoff as well as the reliance of fertilizer production on finite non-renewable resources such as mined phosphate- and potassium-bearing rocks. Indeed, recent volatility in food and agricultural commodity prices, especially phosphate fertilizer, has raised concerns about emerging constraints on fertilizer production with consequences for its affordability in the developing world. We examined 30 years of monthly prices of fertilizer commodities (phosphate rock, urea, and potassium) for comparison with three food commodities (maize, wheat, and rice) and three non-agricultural commodities (gold, nickel, and petroleum). Here we show that all commodity prices, except gold, had significant change points between 2007-2009, but the fertilizer commodities, and especially phosphate rock, showed multiple symptoms of nonlinear critical transitions. In contrast to fertilizers and to rice, maize and wheat prices did not show significant signs of nonlinear dynamics. From these results we infer a recent emergence of a scarcity price in global fertilizer markets, a result signaling a new high price regime for these essential agricultural inputs. Such a regime will challenge on-going efforts to establish global food security but may also prompt fertilizer use practices and nutrient recovery strategies that reduce eutrophication.

  1. Regime shift in fertilizer commodities indicates more turbulence ahead for food security.

    Directory of Open Access Journals (Sweden)

    James J Elser

    Full Text Available Recent human population increase has been enabled by a massive expansion of global agricultural production. A key component of this "Green Revolution" has been application of inorganic fertilizers to produce and maintain high crop yields. However, the long-term sustainability of these practices is unclear given the eutrophying effects of fertilizer runoff as well as the reliance of fertilizer production on finite non-renewable resources such as mined phosphate- and potassium-bearing rocks. Indeed, recent volatility in food and agricultural commodity prices, especially phosphate fertilizer, has raised concerns about emerging constraints on fertilizer production with consequences for its affordability in the developing world. We examined 30 years of monthly prices of fertilizer commodities (phosphate rock, urea, and potassium for comparison with three food commodities (maize, wheat, and rice and three non-agricultural commodities (gold, nickel, and petroleum. Here we show that all commodity prices, except gold, had significant change points between 2007-2009, but the fertilizer commodities, and especially phosphate rock, showed multiple symptoms of nonlinear critical transitions. In contrast to fertilizers and to rice, maize and wheat prices did not show significant signs of nonlinear dynamics. From these results we infer a recent emergence of a scarcity price in global fertilizer markets, a result signaling a new high price regime for these essential agricultural inputs. Such a regime will challenge on-going efforts to establish global food security but may also prompt fertilizer use practices and nutrient recovery strategies that reduce eutrophication.

  2. Knowledge regarding fertility preservation in cancer patients: a population-based survey among Brazilian people during the Pink October awareness event.

    Science.gov (United States)

    Chehin, Mauricio B; Bonetti, Tatiana Cs; Serafini, Paulo C; Motta, Eduardo LA

    2017-06-01

    The aim of this study was to assess the knowledge about the risk of infertility in cancer patients after treatment, and the options for fertility preservation based on a survey carried out during the 2013 Pink October campaign. This survey was carried out during the 2013 Pink October event in the most important public park of São Paulo, Brazil. Approximately 900 people expressed interest in learning about breast cancer prevention and fertility preservation by participating in workshops, and 242 people filled out a questionnaire. Most of the respondents (78.5%) were women, and one-fourth (25%) had at least one relative with gynecological cancer. Among women over 40 years of age, 86.3% had been screened for breast cancer at some point. However, few participants (34.0%) were aware that cancer treatment can lead to infertility or had heard about fertility preservation options (22.0%). Having a relative with cancer did not influence their knowledge about fertility preservation (22.4% versus 21.3%; p=0.864). However, a higher educational level was significantly associated with more knowledge about the effects of cancer on fertility and options for fertility preservation. The majority of participants did not have knowledge about the impact of oncologic treatment on fertility and did not know that there are options to preserve fertility in cancer patients. Awareness of infertility risk factors is an essential first step to safeguard future fertility, and therefore, more educational initiatives are needed to spread knowledge about oncofertility.

  3. Stable, fertile, high polyhydroxyalkanoate producing plants and methods of producing them

    Energy Technology Data Exchange (ETDEWEB)

    Bohmert-Tatarev, Karen; McAvoy, Susan; Peoples, Oliver P.; Snell, Kristi D.

    2015-08-04

    Transgenic plants that produce high levels of polyhydroxybutyrate and methods of producing them are provided. In a preferred embodiment the transgenic plants are produced using plastid transformation technologies and utilize genes which are codon optimized. Stably transformed plants able to produce greater than 10% dwt PHS in tissues are also provided.

  4. The ever-increasing CO2 seasonal cycle amplitude: contributions from high latitude warming, CO2 fertilization, and the agricultural Green Revolution

    Science.gov (United States)

    Zeng, N.; Martin, C.; Zhao, F.; Collatz, G. J.; Kalnay, E.; Salawitch, R. J.; West, T. O.; Guanter, L.

    2014-12-01

    Human activities has tranformed the Earth's surface in complex ways. Here we show that not only land cover change, but also the management intensity, namely the intensification of agriculture through the Green Revolution has had a profound impact on the carbon cycle. A long-standing puzzle in the global carbon cycle is the increase in the amplitude of the seasonal cycle of atmospheric CO2. This increase likely reflects enhanced biological activity in the Northern Hemisphere (NH). It has been hypothesized that vegetation growth may have been stimulated by higher concentrations of CO2 as well as warming in recent decades, but the role of such specific mechanisms has not been quantified and they have been unable to explain the full range and magnitude of observations. Here we suggest another potential driver of the increased seasonal amplitude: the intensification of agriculture from the Green Revolution to feed a rising population, that led to a 3-fold increase in world crop production over the last 5 decades. Our analysis of CO2 data and atmospheric inversions shows a robust 15% long-term increase in CO2 seasonal amplitude from 1961 to 2010 that is punctuated by large decadal and interannual variations. The three pillars of the Green Revolution, consisting of high yield cultivars, fertilizer use, and irrigation, are represented in a terrestrial carbon cycle model. The results reveal that the long-term increase in CO2 seasonal amplitude arises from two major regions in the NH: the mid-latitude cropland between 25N-60N that encompasses the world's major agriculture zones in Asia, Europe and North America, and the high-latitude natural vegetation between 50N-70N that includes much of the Northern boreal forests, tundra and some deciduous forests. The long-term trend of seasonal amplitude is 0.3% per year, of which sensitivity experiments attribute 43% to land use change, 31% to climate variability and change, and 26% to CO2 fertilization. Our results suggest that human

  5. Social networks and fertility

    Directory of Open Access Journals (Sweden)

    Laura Bernardi

    2014-03-01

    Full Text Available Background: The fields of demography, sociology, and socio-psychology have been increasingly drawing on social network theories, which posit that individual fertility decision-making depends in part on the fertility behavior of other members of the population, and on the structure of the interactions between individuals. After reviewing this literature, we highlight the benefits of taking a social network perspective on fertility and family research. Objective: We review the literature that addresses the extent to which social mechanisms, such as social learning, social pressure, social contagion, and social support, influence childbearing decisions. Methods: We review the most recent contributions of the social networks approach for the explanation of fertility dynamics in contemporary post-industrial societies. Conclusions: We find that all of the social mechanisms reviewed influence the beliefs and norms individuals hold regarding childbearing, their perceptions of having children, and the context of opportunities and constraints in which childbearing choices are made. The actual impact of these mechanisms on fertility tempo and quantum strongly depends on the structure of social interaction.

  6. Genetic Diversity and Population Structure of Ethiopian Sheep Populations Revealed by High-Density SNP Markers.

    Science.gov (United States)

    Edea, Zewdu; Dessie, Tadelle; Dadi, Hailu; Do, Kyoung-Tag; Kim, Kwan-Suk

    2017-01-01

    Sheep in Ethiopia are adapted to a wide range of environments, including extreme habitats. Elucidating their genetic diversity is critical for improving breeding strategies and mapping quantitative trait loci associated with productivity. To this end, the present study investigated the genetic diversity and population structure of five Ethiopian sheep populations exhibiting distinct phenotypes and sampled from distinct production environments, including arid lowlands and highlands. To investigate the genetic relationships in greater detail and infer population structure of Ethiopian sheep breeds at the continental and global levels, we analyzed genotypic data of selected sheep breeds from the Ovine SNP50K HapMap dataset. All Ethiopian sheep samples were genotyped with Ovine Infinium HD SNP BeadChip (600K). Mean genetic diversity ranged from 0.29 in Arsi-Bale to 0.32 in Menz sheep, while estimates of genetic differentiation among populations ranged from 0.02 to 0.07, indicating low to moderate differentiation. An analysis of molecular variance revealed that 94.62 and 5.38% of the genetic variation was attributable to differences within and among populations, respectively. Our population structure analysis revealed clustering of five Ethiopian sheep populations according to tail phenotype and geographic origin-i.e., short fat-tailed (very cool high-altitude), long fat-tailed (mid to high-altitude), and fat-rumped (arid low-altitude), with clear evidence of admixture between long fat-tailed populations. North African sheep breeds showed higher levels of within-breed diversity, but were less differentiated than breeds from Eastern and Southern Africa. When African breeds were grouped according to geographic origin (North, South, and East), statistically significant differences were detected among groups (regions). A comparison of population structure between Ethiopian and global sheep breeds showed that fat-tailed breeds from Eastern and Southern Africa clustered

  7. A small field for fertile science: the low visibility of reproductive science in high impact journals.

    Science.gov (United States)

    Duncan, Francesca E; Derman, Benjamin; Woodruff, Teresa K

    2014-05-01

    Our success as a field and as individuals in reproductive science and medicine relies on our ability to produce high quality work that has broad visibility and impact. A common metric for assessing such success is the quantity of publications that are published in journals with high impact factors. It is unclear, however, how frequently work related to reproductive science and medicine actually appears in what are considered the highest impact journals. To address this gap in knowledge, we first determined how the field of reproductive biology in general compared to other research areas in terms of composite journal impact factor. Second, using a targeted search approach in the PubMed database, we examined the relationship between a journal's impact factor and the number of reproductive research articles published per journal issue. We found that compared to other major scientific disciplines, our field lacks journals with impact factors above 4. In addition, primary original research articles on reproduction-irrespective of male or female search terms-do not appear often in high impact journals. Instead, there is an increased percentage of secondary reproductive literature in high impact journals compared to topic-specific journals of lower impact. There are likely several explanations for why reproductive science and medicine has low visibility, including the field's small relative size, its lack of a specific disease and associated strong advocacy, and its surrounding social, ethical, and political unease. Nevertheless, there are concrete actions we can take to minimize the role of impact factor in our evaluation while simultaneously increasing influence through global awareness of the importance and need for reproductive research.

  8. Disentangling seasonal bacterioplankton population dynamics by high-frequency sampling.

    Science.gov (United States)

    Lindh, Markus V; Sjöstedt, Johanna; Andersson, Anders F; Baltar, Federico; Hugerth, Luisa W; Lundin, Daniel; Muthusamy, Saraladevi; Legrand, Catherine; Pinhassi, Jarone

    2015-07-01

    Multiyear comparisons of bacterioplankton succession reveal that environmental conditions drive community shifts with repeatable patterns between years. However, corresponding insight into bacterioplankton dynamics at a temporal resolution relevant for detailed examination of variation and characteristics of specific populations within years is essentially lacking. During 1 year, we collected 46 samples in the Baltic Sea for assessing bacterial community composition by 16S rRNA gene pyrosequencing (nearly twice weekly during productive season). Beta-diversity analysis showed distinct clustering of samples, attributable to seemingly synchronous temporal transitions among populations (populations defined by 97% 16S rRNA gene sequence identity). A wide spectrum of bacterioplankton dynamics was evident, where divergent temporal patterns resulted both from pronounced differences in relative abundance and presence/absence of populations. Rates of change in relative abundance calculated for individual populations ranged from 0.23 to 1.79 day(-1) . Populations that were persistently dominant, transiently abundant or generally rare were found in several major bacterial groups, implying evolution has favoured a similar variety of life strategies within these groups. These findings suggest that high temporal resolution sampling allows constraining the timescales and frequencies at which distinct populations transition between being abundant or rare, thus potentially providing clues about physical, chemical or biological forcing on bacterioplankton community structure. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  9. Fertility in Islamic Republic of Iran: Levels, Trends and Differentials during Three Decades (1967-1996

    Directory of Open Access Journals (Sweden)

    Kazem Mohammad

    2002-12-01

    The detailed nature of these data collected for each birth enabled fertility rates to be calculated for exact periods before the survey, for exact calendar years. Higher fertility rates were found for the period 10-15 and 15-20 years preceding the survey. These high fertility levels are probably due to some socio-economic changes in favor of higher level of fertility immediately after the 1979 revolution. However the results of the present survey show during 1967-1996, the TFR1 had dropped from 6.38 to 2.88 (an expected TFR based on fertility behavior during 1992-96. This decline was probably due to delay in marriage and policy changes in favor of population control particularly since 1987. Despite this potential fertility decline in recent years, Iran is expected to face a baby boom as the offspring who were born during the 1976-86 reach to the reproductive age in the coming decades.

  10. Does broadband internet affect fertility?

    OpenAIRE

    Billari, Francesco C.; Giuntella, Osea; Stella, Luca

    2017-01-01

    The spread of high-speed Internet epitomizes the digital revolution, affecting several aspects of our life. Using German panel data, we test whether the availability of broadband Internet influences fertility choices in a low-fertility setting, which is well-known for the difficulty to combine work and family life. We exploit a strategy devised by Falck et al. (2014) to obtain causal estimates of the impact of broadband on fertility. We find positive effects of highspeed Internet availability...

  11. Economics of fertility in high-yielding dairy cows on confined TMR systems.

    Science.gov (United States)

    Cabrera, V E

    2014-05-01

    The objective of this review paper was to summarise the latest findings in dairy cattle reproductive economics with an emphasis on high yielding, confined total mixed ration systems. The economic gain increases as the reproductive efficiency improves. These increments follow the law of diminishing returns, but are still positive even at high reproductive performance. Reproductive improvement results in higher milk productivity and, therefore, higher milk income over feed cost, more calf sales and lower culling and breeding expenses. Most high-yielding herds in the United States use a combination of timed artificial insemination (TAI) and oestrous detection (OD) reproductive programme. The ratio of achievable pregnancies between OD and TAI determines the economic value difference between both and their combinations. Nonetheless, complex interactions between reproductive programme, herd relative milk yield, and type of reproductive programme are reported. For example, higher herd relative milk yield would favour programme relying more on TAI. In addition, improved reproductive efficiency produces extra replacements. The availability of additional replacements could allow more aggressive culling policies (e.g. less services for non-pregnant cows) to balance on-farm supply and demand of replacements. Balancing heifer replacement availability in an efficient reproductive programme brings additional economic benefits. New technologies such as the use of earlier chemical tests for pregnancy diagnosis could be economically effective depending on the goals and characteristics of the farm. Opportunities for individual cow reproductive management within defined reproductive programme exist. These decisions would be based on economic metrics derived from the value of a cow such as the value of a new pregnancy, the cost of a pregnancy loss, or the cost of an extra day open.

  12. Natriuretic peptides: prediction of cardiovascular disease in the general population and high risk populations

    DEFF Research Database (Denmark)

    Hildebrandt, Per

    2009-01-01

    , hypertension and coronary artery disease. This has of course raised interest for the use of the natriuretic peptides as a risk marker and for screening for heart failure with reduced systolic function in these populations. In symptomatic persons and in high risk populations, the natriuretic peptides have...... population, screening would probably not be cost-effective. In populations with a higher pre-test probability for heart failure, as patients with diabetes, hypertension and stable coronary artery disease, screening would presumably be more cost-effective, but evidence for the use in this setting is still......The natriuretic peptides, especially the B-type peptide (BNP) and its inactive split-product N-terminal proBNP (Nt-proBNP) are increasingly used in screening for heart failure, primarily with reduced systolic function, in patients with symptoms suggestive of heart failure, as well in the stable...

  13. De novo assembly of highly diverse viral populations

    Directory of Open Access Journals (Sweden)

    Yang Xiao

    2012-09-01

    Full Text Available Abstract Background Extensive genetic diversity in viral populations within infected hosts and the divergence of variants from existing reference genomes impede the analysis of deep viral sequencing data. A de novo population consensus assembly is valuable both as a single linear representation of the population and as a backbone on which intra-host variants can be accurately mapped. The availability of consensus assemblies and robustly mapped variants are crucial to the genetic study of viral disease progression, transmission dynamics, and viral evolution. Existing de novo assembly techniques fail to robustly assemble ultra-deep sequence data from genetically heterogeneous populations such as viruses into full-length genomes due to the presence of extensive genetic variability, contaminants, and variable sequence coverage. Results We present VICUNA, a de novo assembly algorithm suitable for generating consensus assemblies from genetically heterogeneous populations. We demonstrate its effectiveness on Dengue, Human Immunodeficiency and West Nile viral populations, representing a range of intra-host diversity. Compared to state-of-the-art assemblers designed for haploid or diploid systems, VICUNA recovers full-length consensus and captures insertion/deletion polymorphisms in diverse samples. Final assemblies maintain a high base calling accuracy. VICUNA program is publicly available at: http://www.broadinstitute.org/scientific-community/science/projects/viral-genomics/ viral-genomics-analysis-software. Conclusions We developed VICUNA, a publicly available software tool, that enables consensus assembly of ultra-deep sequence derived from diverse viral populations. While VICUNA was developed for the analysis of viral populations, its application to other heterogeneous sequence data sets such as metagenomic or tumor cell population samples may prove beneficial in these fields of research.

  14. De novo assembly of highly diverse viral populations.

    Science.gov (United States)

    Yang, Xiao; Charlebois, Patrick; Gnerre, Sante; Coole, Matthew G; Lennon, Niall J; Levin, Joshua Z; Qu, James; Ryan, Elizabeth M; Zody, Michael C; Henn, Matthew R

    2012-09-13

    Extensive genetic diversity in viral populations within infected hosts and the divergence of variants from existing reference genomes impede the analysis of deep viral sequencing data. A de novo population consensus assembly is valuable both as a single linear representation of the population and as a backbone on which intra-host variants can be accurately mapped. The availability of consensus assemblies and robustly mapped variants are crucial to the genetic study of viral disease progression, transmission dynamics, and viral evolution. Existing de novo assembly techniques fail to robustly assemble ultra-deep sequence data from genetically heterogeneous populations such as viruses into full-length genomes due to the presence of extensive genetic variability, contaminants, and variable sequence coverage. We present VICUNA, a de novo assembly algorithm suitable for generating consensus assemblies from genetically heterogeneous populations. We demonstrate its effectiveness on Dengue, Human Immunodeficiency and West Nile viral populations, representing a range of intra-host diversity. Compared to state-of-the-art assemblers designed for haploid or diploid systems, VICUNA recovers full-length consensus and captures insertion/deletion polymorphisms in diverse samples. Final assemblies maintain a high base calling accuracy. VICUNA program is publicly available at: http://www.broadinstitute.org/scientific-community/science/projects/viral-genomics/ viral-genomics-analysis-software. We developed VICUNA, a publicly available software tool, that enables consensus assembly of ultra-deep sequence derived from diverse viral populations. While VICUNA was developed for the analysis of viral populations, its application to other heterogeneous sequence data sets such as metagenomic or tumor cell population samples may prove beneficial in these fields of research.

  15. Fertility and marriage behavior in Israel: Diversity, change, and stability

    Directory of Open Access Journals (Sweden)

    Barbara Okun

    2013-03-01

    Full Text Available BACKGROUND Based on aggregate statistics, the population of Israel, as compared to all or most other developed societies, has very high levels of fertility and marriage (e.g. TFR of 2.96 in 2009 and only 9.7Š never married among women aged 40-44 in 2009. However, studying aggregate demographic measures is problematic, because Israel is an extremely heterogeneous society, with family formation patterns differing greatly across numerically important social groups. Until now, little has been documented about the basic fertility and marriage behavior of different population groups. OBJECTIVE We describe the fertility and marriage behavior of populations in Israel, broken down by nationality, religion, religiosity and nativity-status. Although our main focus is on a detailed presentation of fertility patterns, we also look at marriage behavior, as it is closely related to fertility in Israel. METHODS We analyze recently available annual data from the Israel Social Surveys for 2002-2009, which, for the first time in several decades,, provides detailed information on family and household demographic behavior and direct information on level of religiosity. We focus primarily on comparisons across cohorts born from the late 1940s to the late 1960s and between periods in the early and late 2000s. RESULTS We provide a detailed portrait of striking diversity in fertility and marriage behavior across population groups, along with important patterns of change and stability across cohorts and over time. We document findings and differential patterns, some unexpected, regarding comparisons across groups and across cohorts. CONCLUSIONS The descriptive findings form the basis for a clearer understanding of fertility and marriage patterns in different population subgroups in Israel. In addition, the reported results suggest many questions for future research, which are outlined in the paper.

  16. Seroepidemiology of Rubella in Mozambique, 2006-2014: Implications for Rubella Immunization in Settings With High Fertility Rates.

    Science.gov (United States)

    Amade, Nádia Alves; Sultane, Thebora; Augusto, Orvalho; Ali, Sádia; Jani, Ilesh V; Gudo, Eduardo Samo

    2016-10-01

    Rubella and congenital rubella syndrome are highly underreported and neglected in most sub-Saharan countries and vaccination has not yet been incorporated into their national immunization schedules. In this study, we investigated the frequency of immunoglobulin M antibodies against rubella and examined correlations with fertility rates during the period from 2006 to 2014 in Mozambique. We conducted a retrospective analysis of data collected through the routine case-based surveillance system for measles in Mozambique. A total of 7312 serum samples from suspected cases of measles were tested between 2006 and 2014. The median age was 4 years (interquartile range: 1-8 years). Of these, 1331 (18.2%) were positive for immunoglobulin M anti-rubella. The highest frequency of rubella was observed within the 5-9-year-old age group (32.6%). The frequency in the age groups rubella is frequent among women of childbearing age in Mozambique. Considering that early pregnancy is common in Mozambique, this suggests that, in settings such as ours, the introduction of routine rubella vaccination in children should be accompanied by repeated vaccination campaigns targeting older children and adolescents.

  17. Urinary paraben concentrations and in vitro fertilization outcomes among women from a fertility clinic

    Science.gov (United States)

    Mínguez-Alarcón, Lidia; Chiu, Yu-Han; Messerlian, Carmen; Williams, Paige L.; Sabatini, Mary E.; Toth, Thomas L.; Ford, Jennifer B.; Calafat, Antonia M.; Hauser, Russ

    2015-01-01

    Objective To explore the relationship between urinary paraben concentrations and IVF outcomes among women attending an academic fertility center. Design Prospective cohort study. Setting Fertility clinic in a hospital setting. Patient(s) A total of 245 women contributing 356 IVF cycles. Intervention(s) None. Quantification of urinary concentrations of parabens by isotope-dilution tandem mass spectrometry, and assessment of clinical endpoints of IVF treatments abstracted from electronic medical records at the academic fertility center. Main Outcome Measure(s) Total and mature oocyte counts, proportion of high quality embryos, fertilization rates, and rates of implantation, clinical pregnancy and live births. Results The geometric mean of the urinary concentrations of methyl (MP), propyl (PP) and butyl paraben (BP) in our study population were 133, 24 and 1.5 µg/L, respectively. In models adjusted for age, body mass index, race/ethnicity, smoking status and primary infertility diagnosis, urinary MP, PP and BP concentrations were not associated with IVF outcomes, specifically total and mature oocyte counts, proportion of high embryo quality and fertilization rates. Moreover, no significant associations were found between urinary paraben concentrations and rates of implantation, clinical pregnancy and live births. Conclusion(s) Urinary paraben concentrations were not associated with IVF outcomes among women undergoing infertility treatments. PMID:26654974

  18. Urinary paraben concentrations and in vitro fertilization outcomes among women from a fertility clinic.

    Science.gov (United States)

    Mínguez-Alarcón, Lidia; Chiu, Yu-Han; Messerlian, Carmen; Williams, Paige L; Sabatini, Mary E; Toth, Thomas L; Ford, Jennifer B; Calafat, Antonia M; Hauser, Russ

    2016-03-01

    To explore the relationship between urinary paraben concentrations and IVF outcomes among women attending an academic fertility center. Prospective cohort study. Fertility clinic in a hospital setting. A total of 245 women contributing 356 IVF cycles. None. Quantification of urinary concentrations of parabens by isotope-dilution tandem mass spectrometry, and assessment of clinical endpoints of IVF treatments abstracted from electronic medical records at the academic fertility center. Total and mature oocyte counts, proportion of high-quality embryos, fertilization rates, and rates of implantation, clinical pregnancy, and live births. The geometric means of the urinary concentrations of methylparaben, propylparaben, and butylparaben in our study population were 133, 24, and 1.5 μg/L, respectively. In models adjusted for age, body mass index, race/ethnicity, smoking status, and primary infertility diagnosis, urinary methylparaben, propylparaben, and butylparaben concentrations were not associated with IVF outcomes, specifically total and mature oocyte counts, proportion of high embryo quality, and fertilization rates. Moreover, no significant associations were found between urinary paraben concentrations and rates of implantation, clinical pregnancy, and live births. Urinary paraben concentrations were not associated with IVF outcomes among women undergoing infertility treatments. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  19. Genetic differentiation of populations residing in areas of high ...

    Indian Academy of Sciences (India)

    ... Public Lectures · Lecture Workshops · Refresher Courses · Symposia. Home; Journals; Journal of Genetics; Volume 88; Issue 1. Genetic differentiation of populations residing in areas of high malaria endemicity in India. Swapnil Sinha Vandana Arya Sarita Agarwal Indian Genome Variation Consortium Saman Habib.

  20. Stellar populations a guide from low to high redshift

    CERN Document Server

    Renzini, Alvio

    2011-01-01

    This up-to-date reference on stellar populations and development models includes coverage of distant galaxies, chemical evolution and supernovae. Written by highly acclaimed authorities in the field, the book makes use of specific problems to reveal the ""kitchen secrets.""

  1. Obligatory versus elective single embryo transfer in in vitro fertilization. A population-based analysis of data from the U.K. Human Fertilisation and Embryology Authority.

    Science.gov (United States)

    Straughen, Jennifer K; Salihu, Hamisu M; Keith, Louis; Petrozzino, Jeffrey; Jones, Christopher

    2013-01-01

    To determine how obligatory single embryo transfer (SET) and elective SET influence pregnancy outcome. We compared women who underwent obligatory and elective SET using data from a comprehensive, population-based register from the United Kingdom Human Fertilisation and Embryology Authority, which contained all in vitro fertilization (IVF) treatments administered between 1991 and 1998. Generalized estimating equations were used to generate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) to compare clinical pregnancy, live birth, and multiple birth rates. Obligatory and elective SET had similar clinical pregnancy and live birth rates and comparable multiple birth rates. Obligatory and elective SET were equally likely to end in a live birth (OR = 1.08; 95% CI = 0.90, 1.30). Similar results were found after restricting the data to women without previous IVF births (OR = 1.18; 95% CI = 0.98, 1.42) and without previous naturally conceived live births (OR = 1.16; 95% CI = 0.95, 1.43). This study suggests that obligatory SET can achieve pregnancy and live birth rates that are at least as good as elective SET. Equally important is the low multiple birth rate which was maintained in both forms of SET. More studies comparing elective versus obligatory SET can assist with achieving optimal pregnancy rates while preventing multiple births.

  2. Preserving fertility in young patients with lymphoma: an overview

    Directory of Open Access Journals (Sweden)

    Patel B

    2014-12-01

    Full Text Available Bansari Patel, Brooke V Rossi Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Case Western Reserve University, Cleveland, OH, USA Abstract: Fertility preservation affords patients the ability to reproduce after the initial diagnosis and management of such malignancies as Hodgkin's and non-Hodgkin's lymphoma. Certain chemotherapy regimens and pelvic radiotherapy confer a high-risk of subsequent gonadal compromise in both males and females. Fortunately, early counseling and initiation of fertility-preservation strategies promptly after diagnosis enable patients to maintain hope for future reproduction. Well-established methods for fertility preservation include embryo and oocyte cryopreservation in females and sperm cryopreservation in males. These methods enable patients to utilize assisted reproductive technologies, including in vitro fertilization, at the time of desired childbearing in order to ensure genetic offspring. As most of these modalities are not feasible in some patient populations, including prepubescent patients, newer methods of fertility preservation must be created to ensure the ability to produce genetic offspring in lymphoma patients. This review provides insights into the impact of gonadotoxic treatment on ovarian and testicular function, and highlights current modalities in fertility preservation in both males and females. Keywords: fertility preservation, lymphoma, ART, egg freezing

  3. Premarital fertility in Namibia: trends, factors and consequences.

    Science.gov (United States)

    Garenne, Michel; Zwang, Julien

    2006-03-01

    Premarital fertility, defined as fertility before first marriage, was found to be highly prevalent in Namibia. According to data from the 1992 and 2000 DHS surveys, the proportion of premarital births was 43% for all births, and 60% for the first birth. This seemed to be primarily due to a late mean age at first marriage (26.4 years) and low levels of contraception before first marriage. Data were analysed using a variety of demographic methods, including multiple decrement life table and multivariate logistic models. Major variations were found by ethno-linguistic groups: Herero and Nama/Damara had the highest levels of premarital fertility (above 60%); Ovambo and Lozi had intermediate levels of premarital fertility (around 40%); Kavongo and San appeared to have kept a more traditional behaviour of early marriage and low levels of premarital fertility (around 20%). The largest ethno-linguistic group, the Ovambo, were in a special situation, with fast increasing age at marriage and average level of premarital fertility. Whites and mixed races also differed, with Afrikaans-speaking groups having a behaviour closer to the average, whereas other Europeans had less premarital fertility despite an average age at marriage. Ethnic differences remained stable after controlling for various socioeconomic factors, such as urbanization, level of education, wealth, access to mass media, and religion. Results are discussed in light of the population dynamics and political history of Namibia in the 20th century.

  4. Maize Inoculation with Azospirillum brasilense Ab-V5 Cells Enriched with Exopolysaccharides and Polyhydroxybutyrate Results in High Productivity under Low N Fertilizer Input.

    Science.gov (United States)

    Oliveira, André L M; Santos, Odair J A P; Marcelino, Paulo R F; Milani, Karina M L; Zuluaga, Mónica Y A; Zucareli, Claudemir; Gonçalves, Leandro S A

    2017-01-01

    Although Azospirillum strains used in commercial inoculant formulations presents diazotrophic activity, it has been reported that their ability to produce phytohormones plays a pivotal role in plant growth-promotion, leading to a general recommendation of its use in association with regular N-fertilizer doses. In addition, a high variability in the effectiveness of Azospirillum inoculants is still reported under field conditions, contributing to the adoption of the inoculation technology as an additional management practice rather than its use as an alternative practice to the use of chemical inputs in agriculture. To investigate whether the content of stress-resistance biopolymers would improve the viability and performance of Azospirillum inoculants when used as substitute of N-fertilizers, biomass of A. brasilense strain Ab-V5 enriched in exopolysaccharides (EPS) and polyhydroxybutirate (PHB) was produced using a new culture medium developed by factorial mixture design, and the effectiveness of resulting inoculants was evaluated under field conditions. The culture medium formulation extended the log phase of A. brasilense cultures, which presented higher cell counts and increased EPS and PHB contents than observed in the cultures grown in the OAB medium used as control. An inoculation trial with maize conducted under greenhouse conditions and using the biopolymers-enriched Ab-V5 cells demonstrated the importance of EPS and PHB to the long term bacterial viability in soil and to the effectiveness of inoculation. The effectiveness of liquid and peat inoculants prepared with Ab-V5 cells enriched with EPS and PHB was also evaluated under field conditions, using maize as target crop along different seasons, with the inoculants applied directly over seeds or at topdressing under limiting levels of N-fertilization. No additive effect on yield resulted from inoculation under high N fertilizer input, while inoculated plants grown under 80% reduction in N fertilizer

  5. Maize Inoculation with Azospirillum brasilense Ab-V5 Cells Enriched with Exopolysaccharides and Polyhydroxybutyrate Results in High Productivity under Low N Fertilizer Input

    Directory of Open Access Journals (Sweden)

    André L. M. Oliveira

    2017-09-01

    Full Text Available Although Azospirillum strains used in commercial inoculant formulations presents diazotrophic activity, it has been reported that their ability to produce phytohormones plays a pivotal role in plant growth-promotion, leading to a general recommendation of its use in association with regular N-fertilizer doses. In addition, a high variability in the effectiveness of Azospirillum inoculants is still reported under field conditions, contributing to the adoption of the inoculation technology as an additional management practice rather than its use as an alternative practice to the use of chemical inputs in agriculture. To investigate whether the content of stress-resistance biopolymers would improve the viability and performance of Azospirillum inoculants when used as substitute of N-fertilizers, biomass of A. brasilense strain Ab-V5 enriched in exopolysaccharides (EPS and polyhydroxybutirate (PHB was produced using a new culture medium developed by factorial mixture design, and the effectiveness of resulting inoculants was evaluated under field conditions. The culture medium formulation extended the log phase of A. brasilense cultures, which presented higher cell counts and increased EPS and PHB contents than observed in the cultures grown in the OAB medium used as control. An inoculation trial with maize conducted under greenhouse conditions and using the biopolymers-enriched Ab-V5 cells demonstrated the importance of EPS and PHB to the long term bacterial viability in soil and to the effectiveness of inoculation. The effectiveness of liquid and peat inoculants prepared with Ab-V5 cells enriched with EPS and PHB was also evaluated under field conditions, using maize as target crop along different seasons, with the inoculants applied directly over seeds or at topdressing under limiting levels of N-fertilization. No additive effect on yield resulted from inoculation under high N fertilizer input, while inoculated plants grown under 80% reduction in

  6. FERTILITY VARIATION of Melaleuca cajuput subspcajuputi AND ITS IMPLICATION IN SEED ORCHARD MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Noor Khomsah Kartikawati

    2016-10-01

    Full Text Available Information about fertility variation of flowering trees in seed orchard including determining the quality of seed production and estimating the genetic diversity are still lacking. This paper evaluates fertility variation, effective population size and genetic diversity among cajuput trees in seedling seed orchard at Paliyan, Gunungkidul for optimizing seed orchard management. A total of 160 trees were observed in three flowering periods of 2011-2013. The fertility based on the number of flowers and fruits were registered for each tree at the age of 12, 13 and 14 years. Results show that there are similar patterns of fertility after three years observation. Sibling coefficients (Ψ which show fertility variation during three flowering periods are 1.39, 1.25 and 1.43 respectively. They show deviation from random mating, because of individual imbalance for producing flowers and fruits. However, the number of fertile trees was comparatively higher at 2011. More than 15 families of effective population size were recorded each year and supported more than 75% individuals in seed orchard to contribute flowers and seeds. High value of genetic diversity was calculated based on fertility variation (0.965, 0.967 and 0.957, respectively. Fertility variation led to consequence on seed deployment, including seeds of fertile families which should be collected equally and mixed to compose equal proportion of seeds and to avoid domination of highly fertility families and genetic drift. Silvicultural treatments in seed orchard management were indispensable to promote fertility uniformity and to increase effective population size in seed orchard for obtaining maximal genetic gain.

  7. Development of the knowledge of fertility and fertility preservation scale

    Directory of Open Access Journals (Sweden)

    McNees P

    2012-04-01

    Full Text Available Angela Jukkala1, Karen Meneses1, Andres Azuero1, June Cho1, Patrick McNees1,21School of Nursing, 2School of Health Professions, University of Alabama at Birmingham, Birmingham, AL, USAObjective: Infertility is a severe and often underestimated consequence of successful treatment for breast cancer. Ensuring young breast cancer survivors receive patient-centered health information on the impact of treatment on fertility and fertility preservation options in a timely manner is a critical component of high quality nursing care. The objective of this manuscript is to report the process used to develop and examine the reliability and validity of an instrument to measure a breast cancer survivor’s self-assessed knowledge of fertility and fertility preservation.Design: A scale development and descriptive study.Setting: Online and global.Participants: Ninety-two young breast cancer survivors (ages 25–45 years.Methods: Participants completed the Knowledge of Fertility and Fertility Preservation (KF Scale as part of their participation in a larger study, the Fertility Cancer Project (FCP.Results: An exploratory factor analysis revealed five domains: normal reproductive function; general information about fertility; cancer treatment factors affecting fertility; infertility information; and alternative parenting options. A confirmatory factor analysis confirmed the validity of the construct with a demonstrated good fit between the factor structure of the new scale and the observed data. Many participants self-assessed their overall knowledge of fertility and fertility preservation as “a little” and the majority rated their knowledge of infertility information as “a little”.Conclusion: The KF Scale can be used to provide useful information to support health care professionals in the development of patient-centered education that is responsive to the unique needs of each young breast cancer survivor. The initial testing of the KF Scale indicates

  8. Hospital mental health admissions in women after unsuccessful infertility treatment and in vitro fertilization: an Australian population-based cohort study.

    Science.gov (United States)

    Stewart, Louise M; Holman, C D'Arcy J; Semmens, James B; Preen, David; Mai, Qun; Hart, Roger

    2015-01-01

    To examine the association between in vitro fertilization (IVF) and later admission to hospital with a mental health diagnosis in women who remained childless after infertility treatment. This was a population-based cohort study using linked administrative hospital and registry data. The study population included all women commencing hospital treatment for infertility in Western Australia between the years 1982 and 2002 aged 20-44 years at treatment commencement who did not have a recorded birth by the end of follow-up (15 August 2010) and did not have a hospital mental health admission prior to the first infertility admission (n=6,567). Of these, 2,623 women had IVF and 3,944 did not. We used multivariate Cox regression modeling of mental health admissions and compared women undergoing IVF treatment with women having infertility treatment but not IVF. Over an average of 17 years of follow-up, 411 women in the cohort were admitted to hospital with a mental health diagnosis; 93 who had IVF and 318 who did not. The unadjusted hazard ratio (HR) for a hospital mental health admission comparing women who had IVF with those receiving other infertility treatment was 0.50 (95% confidence interval [CI] 0.40-0.63). After adjustment for age, calendar year and socio-economic status the HR was 0.56 (95% CI 0.44-0.71). IVF treatment is associated with a reduced risk of hospital mental health admissions in women after unsuccessful infertility treatment. This may be explained by the healthy cohort effect.

  9. Unmet fertility expectations and the perception of fertility problems in ...

    African Journals Online (AJOL)

    This study analyses in-depth interviews with 15 women and 11 men living in a rural Malawian village to know how fertility problems are identified and interpreted in a context of high fertility demand. Results of the analysis show that although ideal family size may be falling, expectations to quickly achieve pregnancies remain ...

  10. Slovakia: Fertility between tradition and modernity

    Directory of Open Access Journals (Sweden)

    Danuša Jurcová

    2008-07-01

    Full Text Available In the last 60 years, Slovakia has experienced comparatively high and most recently very low fertility, long periods of stable fertility alternating with periods of changes, periods of substantial as well as lesser state interventions. Fertility was above replacement in 1990 and declined to the lowest-low levels during the period of transformation. Postponement of life course transitions - leaving the parental home, marrying and becoming a parent - became widespread among younger cohorts after 1990. High unemployment of young adults, increasing economy-driven migration and problems to gain a stable job contribute to this phenomenon. Reproductive behavior is changing, yet Slovak society remains culturally conservative. The dominant form of partnership is marriage, although extra-marital childbearing is rising. Cohabitation is spreading mainly as a prelude to marriage but is not widely approved. Population measures have a long tradition, although 15 years after regime change their nature is very different than that of the state socialist era. Considerable attention was and is being paid to population problems, however, the government has not designed and implemented a comprehensive system of family and population policies.

  11. A cross-over in Mexican and Mexican-American fertility rates: Evidence and explanations for an emerging paradox

    Directory of Open Access Journals (Sweden)

    Patrick Heuveline

    2005-03-01

    Full Text Available Against a backdrop of two new developments in the fertility behavior of the Mexican- Origin population in the U.S., the present discussion will update contemporary Mexican-Origin fertility patterns and address several theoretical weaknesses in the current approach to minority group fertility. Data come from six national surveys (three from Mexico and three from the U.S. that cover a twenty-five year period (1975-2000. The findings demonstrate dramatic decreases in the fertility rates in Mexico at the same time that continuous increases have been documented in the fertility rates of third-or-later generation Mexican-Americans in the U.S., particularly at younger ages. These changes necessitate a reexamination of the ubiquitous theory that Mexican pronatalist values are responsible for the high fertility rates found within the Mexican-Origin population in the U.S. Instead, they point to the increasing relevance of framing the fertility behavior of the Mexican-Origin population within a racial stratification perspective that stresses the influence of U.S. social context on fertility behavior. As a step in this direction, the analysis examines fertility patterns within the Mexican-Origin population in the U.S. Special attention is given to the role of nativity/generational status in contributing to within group differences.

  12. Low forager fertility: demographic characteristic or methodological artifact?

    Science.gov (United States)

    Early, J D

    1985-09-01

    Anthropological literature has long held that traditional foraging populations have low fertility levels. This research examines the number of live births per woman for 9 non-western forager groups who have been investigated in the last 20 years. Data are derived from 1) birth registration systems, 2) surveys conducted during short stays with the group, and 3) surveys conducted as part of longer ethnographic studies. Fertility rates for the groups are 1) 3.5 for the Kiunga area of Papula, New Guinea, 2) 4.2 for Northern Territory Australian aborigines, 3) 5.0 for Cayapo groups in Brazil, 4) 5.3 for Hiowe people of New Guinea, 5) 5.7 for 3 Xavante groups in Brazil, 6) 6.0 for West Alaskan Eskimos, 7) 6.9 for Nunamiut Eskimos of Alaska, 8) 7.6 for the Bisman-Asmat group of Indonesian New Guinea, and 9) 8.4 for the Winikina Warao of Venezuela. Since fertility rates are highest when ethnographic studies, which allow for question clarification, memory recall, and cross-checking, are used, the author believes that high fertility rates most accurately represent forager societies. Research on the Dobe ]Kung (fertility rate - 4.7), may contradict these findings, but the author believes that the ]Kung fertility rates are higher than reported because of infanticide practices, sexual abstinence during lactation, and disease related fertility problems. In summary, the study finds high fertility (7-9 births) in traditional foraging societies. Although the study examines small populations, correlation strength and overall consistency help verify the results.

  13. The population program shifts to 'high-scenario' targets.

    Science.gov (United States)

    Aragon-choudury, P

    1986-01-01

    The Philippine Population Program would like to achieve a replacement level of 1 daughter per childbearing woman by the year 2000 to reduce the population growth rate to 2% by 1992. Laing projected that high performance by the National Population Program would mean continued increase of sterilization prevalence at an average 1978-1983 rate. Strategies have been adopted to strengthen information-education-communication efforts, to attain higher contraceptive prevalence rates and use-effectiveness, to develop manpower, to achieve self-reliance, and to effect better program coordination, monitoring, research use. Effective service delivery will be a key to achieving the high-scenario targets. Effective use of natural family planning (NFP), will help in achieving the high-scenario goals. Apart from the heavy demand on NFP follow-up, need for prompt delivery of supplies, and lack of doctors and nurses, other factors may impede the high-scenario targets. Saniel believes that program workers should be allowed to insert IUDs and to dispense pills. Under the cost-recovery and cost-sharing schemes of the high-scenario targets, only sterilization will be done for free. It might affect the campaign for increased acceptors, but the start for self-reliance must happen now.

  14. Women's education and fertility behaviour.

    Science.gov (United States)

    1993-12-01

    The education of women results in changes in women's health status, family well being, and fertility decline. The aim of human rights and social justice is also served by increasing women's educational levels. A review of the trends in developing countries has shown that there is a strong correlation between advanced female education (10 or more years) and lower fertility. Data for 26 countries was presented in table form for total fertility rates by years of education. There were many differences in the patterns of fertility by educational level based on country level of development. The data appeared to show stronger correlations between fertility and education in more prosperous societies; culture and social structure also influenced fertility. Partial primary education has been shown in some countries to be related to increased fertility. A UN study found a curvilinear relationship between fertility and education in 14 out of 38 countries with World Fertility Surveys. There were only 3 countries with Demographic and Health Surveys which showed the curvilinear pattern. The UN study confirmed that maternal education was related to shorter durations of postpartum abstinence and short durations of lactation. Caution was urged in interpreting that an increase in a few years of schooling in a dominant rural, illiterate population would facilitate rapid fertility decline. A critical threshold effect for educational attainment was found in mainly the least developed countries. Female education has direct and indirect effects on fertility. Education may affect breast feeding patterns, contraceptive use, social norms about small families, later age at marriage, and later age at first birth. The suggestion was that education provided for reproductive choice and reduces the gap between actual and desired family size. At the country and individual level of analysis, contraceptive use was linked with education. Effective contraceptive use was still however impeded by

  15. Fertility Profile Following Induced Abortion in Calabar, Nigeria ...

    African Journals Online (AJOL)

    Context: The incidence of induced abortion in Nigeria is high. Pelvic infection as a complication of this abortion is also common and with the rising prevalence of infertility in the population, there is a need to assess the impact of induced abortions on fertility in our women. Objective: To establish the impact of induced abortion ...

  16. Inherent Soil Fertility as Affected by Rhizobium Inoculation and ...

    African Journals Online (AJOL)

    else

    (282.00) and NDW (0.8182 g) were observed at Haramaya and Hirna sites, respectively, where the inherent soil fertility, .... oC, the count of the Rhizobium strain was 1 x 109 g–1 carrier material. The population of rhizobia in the ..... application rates, which could also favor high symbiotic N2 fixation (Rys and. Bonish 1981).

  17. Purging deleterious mutations under self fertilization: paradoxical recovery in fitness with increasing mutation rate in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Levi T Morran

    Full Text Available BACKGROUND: The accumulation of deleterious mutations can drastically reduce population mean fitness. Self-fertilization is thought to be an effective means of purging deleterious mutations. However, widespread linkage disequilibrium generated and maintained by self-fertilization is predicted to reduce the efficacy of purging when mutations are present at multiple loci. METHODOLOGY/PRINCIPAL FINDINGS: We tested the ability of self-fertilizing populations to purge deleterious mutations at multiple loci by exposing obligately self-fertilizing populations of Caenorhabditis elegans to a range of elevated mutation rates and found that mutations accumulated, as evidenced by a reduction in mean fitness, in each population. Therefore, purging in obligate selfing populations is overwhelmed by an increase in mutation rate. Surprisingly, we also found that obligate and predominantly self-fertilizing populations exposed to very high mutation rates exhibited consistently greater fitness than those subject to lesser increases in mutation rate, which contradicts the assumption that increases in mutation rate are negatively correlated with fitness. The high levels of genetic linkage inherent in self-fertilization could drive this fitness increase. CONCLUSIONS: Compensatory mutations can be more frequent under high mutation rates and may alleviate a portion of the fitness lost due to the accumulation of deleterious mutations through epistatic interactions with deleterious mutations. The prolonged maintenance of tightly linked compensatory and deleterious mutations facilitated by self-fertilization may be responsible for the fitness increase as linkage disequilibrium between the compensatory and deleterious mutations preserves their epistatic interaction.

  18. Prediction of porcine male fertility

    NARCIS (Netherlands)

    Broekhuijse, M.L.W.J.

    2012-01-01

    Life starts with fertilisation. Variation in fertility is caused by both farm and sow related parameters and boar and semen related parameters. Therefore, achieving high fertility is not obvious. Predominantly, artificial insemination (AI) is used for breeding pigs. The advantage of AI is that you

  19. [Fertility in Colombia].

    Science.gov (United States)

    Ojeda, G

    1998-06-01

    Demography, which should be the basis for planning of any program or project, has traditionally been ignored by Colombian governments. No population statistics are available for the pre-Conquest period in Colombia. Statistics during the Colonial era were based on population counts for division of lands, taxation, and similar considerations. The first census was undertaken around 1770. Colombia's most recent census was in 1993, and another is being prepared for 2000. The censuses have been useful for development purposes despite their significant limitations of completeness and accuracy. Colombia's population in 1997 was estimated at 40,300,000, making it the third most populous country of Latin America after Brazil and Mexico. Fertility has declined considerably since 1965. Colombia's crude birth rate is believed to have exceeded 50/1000 in the 18th and 19th centuries and was estimated at 45/1000 by the Latin American Demographic Center for the first half of the 20th century. The crude birth rate was 41.3/1000 in 1968, 33.1/1000 in 1973, 30/1000 in 1980, and around 26/1000 in 1990 and 1995. The total fertility rate was estimated at 7.0 in 1960-65, 6.7 in 1969, 4.5 in 1973, 3.2 in 1985, and 2.9 in 1995. Fertility declined most appreciably before 1975, but rates continue to drop in rural as well as urban areas and in all geographic zones. For Colombia as a whole the total fertility rate is 4.8 for women with less than 5 years of schooling and 2.4 for those with 8 or more years. It is 2.7 in urban and 4.4 in rural areas.

  20. Increasing Efficiency of Soil Fertility Map for Rice Cultivation Using Fuzzy Logic, AHP and GIS

    Directory of Open Access Journals (Sweden)

    javad seyedmohammadi

    2017-02-01

    Full Text Available Introduction: With regard to increasing population of country, need to high agricultural production is essential. The most suitable method for this issue is high production per area unit. Preparation much food and other environmental resources with conservation of biotic resources for futures will be possible only with optimum exploitation of soil. Among effective factors for the most production balanced addition of fertilizers increases production of crops higher than the others. With attention to this topic, determination of soil fertility degree is essential tobetter use of fertilizers and right exploitation of soils. Using fuzzy logic and Analytic Hierarchy Process (AHP could be useful in accurate determination of soil fertility degree. Materials and Methods: The study area (at the east of Rasht city is located between 49° 31' to 49° 45' E longitude and 37° 7' to 37° 27' N latitude in north of Guilan Province, northern Iran, in the southern coast of the Caspian sea. 117 soil samples were derived from0-30 cm depth in the study area. Air-dried soil samples were crushed and passed through a 2mm sieve. Available phosphorus, potassium and organic carbon were determined by sodium bicarbonate, normal ammonium acetate and corrected walkly-black method, respectively. In the first stage, the interpolation of data was done by kriging method in GIS context. Then S-shape membership function was defined for each parameter and prepared fuzzy map. After determination of membership function weight parameters maps were determined using AHP technique and finally soil fertility map was prepared with overlaying of weighted fuzzy maps. Relative variance and correlation coefficient criteria used tocontrol groups separation accuracy in fuzzy fertility map. Results and Discussion: With regard to minimum amounts of parameters looks some lands of study area had fertility difficulty. Therefore, soil fertility map of study area distinct these lands and present soil

  1. A simple and fast method for assessment of the nitrogen–phosphorus–potassium rating of fertilizers using high-resolution continuum source atomic and molecular absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bechlin, Marcos André; Fortunato, Felipe Manfroi; Moutinho da Silva, Ricardo; Ferreira, Edilene Cristina; Gomes Neto, José Anchieta, E-mail: anchieta@iq.unesp.br

    2014-11-01

    The determination of N, P, and K in fertilizers by high-resolution continuum source flame atomic and molecular absorption spectrometry is proposed. Under optimized conditions, measurements of the diatomic molecules NO and PO at 215.360 and 247.620 nm, respectively, and K using the wing of the alternative line at 404.722 nm allowed calibration curves to be constructed in the ranges 500–5000 mg L{sup −1} N (r = 0.9994), 100–2000 mg L{sup −1} P (r = 0.9946), and 100–2500 mg L{sup −1} K (r = 0.9995). Commercial fertilizers were analyzed by the proposed method and the concentrations of N, P, and K were found to be in agreement with those obtained by Kjeldahl, spectrophotometric, and flame atomic emission spectrometry methods, respectively, at a 95% confidence level (paired t-test). A phosphate rock certified reference material (CRM) was analyzed and the results for P and K were in agreement with the reference values. Recoveries from spiked CRM were in the ranges 97–105% (NO{sub 3}{sup −}-N), 95–103% (NH{sub 4}{sup +}-N), 93–103% (urea-N), 99–108% (P), and 99–102% (K). The relative standard deviations (n = 12) for N, P, and K were 6, 4, and 2%, respectively. - Highlights: • A single technique is proposed to analyze NPK fertilizer. • HR-CS FAAS is proposed for the first time for N, P and K determination in fertilizers. • The method employs the same sample preparation and dilution for the three analytes. • Addition of H{sub 2}O{sub 2} allows analysis of fertilizers with different nitrogen species. • Proposal provides advantages over traditional methods in terms of cost and time.

  2. Corn yield and soil fertility with combined use of raw or composted beef manure and inorganic fertilizers on the texas northern high plains

    Science.gov (United States)

    Corn is the biggest crop in the semiarid Texas Northern High Plains, with 350,000 ha harvested annually. About 7.1 million beef cattle are also raised annually in the region, producing more than 16 Mg of manure. Manure is typically removed directly from the open lot pens and land applied as raw ma...

  3. The core root microbiome of sugarcanes cultivated under varying nitrogen fertilizer application.

    Science.gov (United States)

    Yeoh, Yun Kit; Paungfoo-Lonhienne, Chanyarat; Dennis, Paul G; Robinson, Nicole; Ragan, Mark A; Schmidt, Susanne; Hugenholtz, Philip

    2016-05-01

    Diazotrophic bacteria potentially supply substantial amounts of biologically fixed nitrogen to crops, but their occurrence may be suppressed by high nitrogen fertilizer application. Here, we explored the impact of high nitrogen fertilizer rates on the presence of diazotrophs in field-grown sugarcane with industry-standard or reduced nitrogen fertilizer application. Despite large differences in soil microbial communities between test sites, a core sugarcane root microbiome was identified. The sugarcane root-enriched core taxa overlap with those of Arabidopsis thaliana raising the possibility that certain bacterial families have had long association with plants. Reduced nitrogen fertilizer application had remarkably little effect on the core root microbiome and did not increase the relative abundance of root-associated diazotrophs or nif gene counts. Correspondingly, low nitrogen fertilizer crops had lower biomass and nitrogen content, reflecting a lack of major input of biologically fixed nitrogen, indicating that manipulating nitrogen fertilizer rates does not improve sugarcane yields by enriching diazotrophic populations under the test conditions. Standard nitrogen fertilizer crops had improved biomass and nitrogen content, and corresponding soils had higher abundances of nitrification and denitrification genes. These findings highlight that achieving a balance in maximizing crop yields and minimizing nutrient pollution associated with nitrogen fertilizer application requires understanding of how microbial communities respond to fertilizer use. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. High-resolution melting analysis (HRMA): a highly sensitive inexpensive genotyping alternative for population studies.

    Science.gov (United States)

    Smith, B L; Lu, C-P; Alvarado Bremer, J R

    2010-01-01

    High-resolution melting analysis (HRMA) is a highly sensitive closed-tube genotyping method used primarily in clinical studies. As the method is rapid, inexpensive and amenable to high throughput, we decided to investigate its applicability to population studies. Small amplicons and unlabelled probes were used to genotype the nuclear genes, lactate dehydrogenase-A (ldh-A), myosin light chain-2 (mlc-2), acidic ribosomal phosphoprotein P0 (ARP) and calmodulin (CaM) in populations of swordfish, Xiphias gladius. Results indicate that HRMA is a powerful genotyping tool to study wild populations. © 2009 Blackwell Publishing Ltd.

  5. Adverse childhood event experiences, fertility difficulties and menstrual cycle characteristics.

    Science.gov (United States)

    Jacobs, Marni B; Boynton-Jarrett, Renee D; Harville, Emily W

    2015-01-01

    Increased childhood adversity may be affect adult fertility, however, the mechanism through which this occurs is unclear. Menstrual cycle abnormalities are predictive of fertility difficulties, and stress influences menstrual cycle characteristics. Here, we assess whether adverse childhood experiences (ACEs) are associated with fertility difficulties and menstrual cycle dysregulation, offering a plausible mechanism for the link between lifetime stress and fertility. From April 2012 to February 2014, 742 pregnant and non-pregnant women aged 18-45 years residing in southeastern Louisiana provided information on childhood adversity and reproductive history. Associations between ACEs and fertility difficulties and menstrual cycle patterns were evaluated. As the number of ACEs increased, risk of fertility difficulties and amenorrhea increased (RR = 1.09, 95% CI 1.05-1.13 and RR = 1.07, 95% CI 1.04-1.10, respectively), while fecundability decreased [fecundability ratio (FR) = 0.97, 95% CI 0.95-1.00]. Compared to women with no adversity, women in the high adversity group were more likely to experience both infertility and amenorrhea (RR = 2.75, 95% CI 1.45-5.21 and RR = 2.54, 95% CI 1.52-4.25, respectively), and reduced fecundability (FR = 0.75, 95% CI 0.56-1.00). Although similar patterns were seen for menstrual cycle irregularity, associations were diminished. Associations did not materially change following adjustment for age, body mass index, race, education, smoking and income. Results are constrained by the self-report nature of the study and the limited generalizability of the study population. To our knowledge, this is the first study to present evidence of a link between childhood stressors, menstrual cycle disruption and fertility difficulties. The effect of childhood stress on fertility may be mediated through altered functioning of the HPA axis, acting to suppress fertility in response to less than optimal reproductive circumstances.

  6. Knowledge regarding fertility preservation in cancer patients: a population-based survey among Brazilian people during the Pink October awareness event

    OpenAIRE

    Chehin, Mauricio B; Bonetti, Tatiana CS; Serafini, Paulo C.; Motta, Eduardo LA

    2017-01-01

    Objective The aim of this study was to assess the knowledge about the risk of infertility in cancer patients after treatment, and the options for fertility preservation based on a survey carried out during the 2013 Pink October campaign. Methods This survey was carried out during the 2013 Pink October event in the most important public park of S?o Paulo, Brazil. Approximately 900 people expressed interest in learning about breast cancer prevention and fertility preservation by participating i...

  7. Fertility desire and associated factors among clients on highly active antiretroviral treatment at finoteselam hospital Northwest Ethiopia: a cross sectional study.

    Science.gov (United States)

    Abbawa, Fassika; Awoke, Worku; Alemu, Yayehirad

    2015-08-11

    The accessibility of antiretroviral treatment changed the lives of persons living with HIV from hopelessness to hopefulness. Thus, many of them decided to have children. In Ethiopia, where there is high prevalence of HIV, level of fertility desire among persons living with HIV could have significant part in safe motherhood and child health. The aim of this study was to assess the level of fertility desire and identify factors associated with it among clients on highly active antiretroviral treatment at Finoteselam Hospital, Northwest Ethiopia. A cross-sectional study design supplemented by in-depth interview was conducted on 422 clients on Highly Active Antiretroviral Treatment from July 1 to August 12, 2013. Structured questionnaire was used to collect the data. Data were entered in to EPi Info version 3.5.1 and exported to SPSS software version 16 for further analysis. Descriptive and summary statistics were computed. Proportions were calculated to estimate fertility desire level. Binary logistic regression model was fitted to identify factors associated with fertility desire. A total of 422 clients were included in the study of which 217 (51.4%) were males. The median age was 33 (IQR = 12) years. A total of 141(33.4%) of clients had desire for having children. Male clients desire children than their female counterparts [AOR = 3.19, 95 % CI: (1.56, 6.51)]. Clients who had no child had more desire for having children than those who had three or more children [AOR = 6.78, 95 % CI: (2.38, 19.27)] and those who had ≤2 years duration on ART had more desire than those with >2 years duration on ART [AOR = 3.64, 95 % CI: (1.74, 7.64)]. Clients who had discussion with ART service provider about sexuality, Fertility desire and family planning had more child desire [AOR = 3.12, 95 % CI: (1.54, 6.32)]. One third of clients have desire to have a child/children in the future. Male clients and clients who have less than or equal to 2 years ART follow up

  8. Methodology for Establishing a Population-Based Birth Cohort Focusing on Couple Fertility and Children’s Development, the Upstate KIDS Study

    Science.gov (United States)

    Buck Louis, Germaine M.; Hediger, Mary L.; Bell, Erin M.; Kus, Christopher A.; Sundaram, Rajeshwari; McLain, Alexander C.; Yeung, Edwina; Hills, Elaine A.; Thoma, Marie E.; Druschel, Charlotte M.

    2015-01-01

    Background Critical data gaps remain regarding infertility treatment and child development. We assessed the utility of a birth certificate registry for developing a population cohort aimed at answering such questions. Methods We utilized the Upstate New York live birth registry (N=201,063) to select births conceived with (n=4,024) infertility treatment or exposed infants, who were then frequency-matched by residence and plurality to a random sample of infants conceived without (n=14,455) treatment or unexposed infants, 2008–2010. Mothers were recruited at 2–4 months postpartum and queried about their reproductive histories including infertility treatment for comparison with birth certificate data. Overall, 1,297 (32%) mothers of exposed and 3,692 of unexposed (26%) infants enrolled. Results Twins represented 22% of each infant group. The percentage of infants conceived with/without infertility treatment was similar whether derived from the birth registry or maternal report: 71% none, 16% drugs or intrauterine insemination, and 14% ART. Concordant reporting between the two data sources was 93% for no treatment, 88% for ART and 83% for fertility drugs, but differed by plurality. Exposed infants had slightly (pcertificates but not maternal report (38.7±2.7 and 38.7±2.9, respectively). Conversely, mean birthweight was comparable using birth certificates (3157±704 and 3194±679 grams, respectively), but differed using maternal report (3167±692 and 3224±661, respectively pcertificate registry is a suitable sampling framework as measured by concordance with maternally reported infertility treatment. Future efforts should address the impact of factors associated with discordant reporting on research findings. PMID:24665916

  9. [Child survival, fertility, and family planning in Africa. Uncertain prospects].

    Science.gov (United States)

    Mbacke, C

    1987-10-01

    externally-imposed improvements. Availability of family planning services becomes an important factor in the extent and speed of fertility decline once the desired number of surviving children becomes smaller than that implied in a natural fertility regime. The author found that sustained fertility declines were usually preceded by mortality declines, but improved health conditions did not automatically lead to fertility declines. The pronatalist attitudes of individual households, rational though they might be, are becoming a problem for African governments burdened by the need to provide services for ever growing populations. Lloyd and Ivanov believe that infant mortality is still too high in most of Africa to encourage family planning; they recommend that sterilization be stressed for families that have achieved their desired size. This work argues however that a future fertility decline is not assured and that reversible contraceptives should be available for the population sectors desiring them.

  10. High dietary fiber intake prevents stroke at a population level.

    Science.gov (United States)

    Casiglia, Edoardo; Tikhonoff, Valérie; Caffi, Sandro; Boschetti, Giovanni; Grasselli, Carla; Saugo, Mario; Giordano, Nunzia; Rapisarda, Valentina; Spinella, Paolo; Palatini, Paolo

    2013-10-01

    This research was aimed at clarifying whether high dietary fiber intake has an impact on incidence and risk of stroke at a population level. In 1647 unselected subjects, dietary fiber intake (DFI) was detected in a 12-year population-based study, using other dietary variables, anagraphics, biometrics, blood pressure, heart rate, blood lipids, glucose, insulin, uricaemia, fibrinogenaemia, erytrosedimentation rate, diabetes, insulin resistance, smoking, pulmonary disease and left ventricular hypertrophy as covariables. In adjusted Cox models, high DFI reduced the risk of stroke. In analysis based on quintiles of fiber intake adjusted for confounders, HR for incidence of stroke was lower when the daily intake of soluble fiber was >25 g or that of insoluble fiber was >47 g. In multivariate analyses, using these values as cut-off of DFI, the risk of stroke was lower in those intaking more that the cut-off of soluble (HR 0.31, 0.17-0.55) or insoluble (HR 0.35, 0.19-0.63) fiber. Incidence of stroke was also lower (-50%, p dietary DFI is inversely and independently associated to incidence and risk of stroke in general population. Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  11. Caste, socio-economic status and fertility -- a study of proximate determinants of fertility in village Riwasa.

    Science.gov (United States)

    Arora, G

    1985-10-01

    The intermediary variables of ritual stratification, i.e., caste, and secular stratification, i.e., socioeconomic status, were examined to explain fertility in a survey of 140 fertile women in Riwasa village, Bhiwani District, Haryana state, India, in 1981. The subjects interviewed were equally divided among 17 castes on the basis of untouchability. The intermediary variables evaluated were caste-consciousness, modernization, conformity to family ethical codes and husband-wife communication. The fertility indices were live births, living children, expected additional births and ideal family size. Results were expressed in percentages. Results of the survey confirmed previous findings that fertility was inversely related to caste and socioeconomic status. These associations were explained here, however, by the behavior of the intermediary variables. Fertility was inversely related to level of modernization and to husband-wife communication. Although caste-consciousness and conformity to family ethical codes were directly related to fertility, even among the higher castes. There were no differences in this study population between high and middle socioeconomic class, probably because the high socioeconomic group in this village resembled middle class in typical urban settings.

  12. High ratings of satisfaction with fertility treatment are common: findings from the Copenhagen Multi-centre Psychosocial Infertility (COMPI) Research Programme

    DEFF Research Database (Denmark)

    Schmidt, L; Holstein, B E; Boivin, J

    2003-01-01

    /delivery and the report of marital benefits resulting from the infertility experience. Lower social class was a significant predictor for satisfaction. CONCLUSIONS: Both men and women in fertility treatment had high ratings on medical and patient-centred care. It seemed that satisfaction with the psychosocial services......BACKGROUND: The aims were: (i). to identify gender differences in evaluation of medical and patient-centred (psychosocial) care in fertility clinics and (ii). to identify predictors of satisfaction. METHODS: An epidemiological prospective study based on questionnaire responses among all new couples......-centred (psychosocial) services. There were no sex differences in the evaluation of treatment except that women were more satisfied than men with how the staff had performed their medical examinations. Satisfaction with medical and patient-centred services was positively associated with a treatment-related pregnancy...

  13. Population and antenatal-based HIV prevalence estimates in a high contracepting female population in rural South Africa

    Science.gov (United States)

    Rice, Brian D; Bätzing-Feigenbaum, Jörg; Hosegood, Victoria; Tanser, Frank; Hill, Caterina; Barnighausen, Till; Herbst, Kobus; Welz, Tanya; Newell, Marie-Louise

    2007-01-01

    Background To present and compare population-based and antenatal-care (ANC) sentinel surveillance HIV prevalence estimates among women in a rural South African population where both provision of ANC services and family planning is prevalent and fertility is declining. With a need, in such settings, to understand how to appropriately adjust ANC sentinel surveillance estimates to represent HIV prevalence in general populations, and with evidence of possible biases inherent to both surveillance systems, we explore differences between the two systems. There is particular emphasis on unrepresentative selection of ANC clinics and unrepresentative testing in the population. Methods HIV sero-prevalence amongst blood samples collected from women consenting to test during the 2005 annual longitudinal population-based serological survey was compared to anonymous unlinked HIV sero-prevalence amongst women attending antenatal care (ANC) first visits in six clinics (January to May 2005). Both surveillance systems were conducted as part of the Africa Centre Demographic Information System. Results Population-based HIV prevalence estimates for all women (25.2%) and pregnant women (23.7%) were significantly lower than that for ANC attendees (37.7%). A large proportion of women attending urban or peri-urban clinics would be predicted to be resident within rural areas. Although overall estimates remained significantly different, presenting and standardising estimates by age and location (clinic for ANC-based estimates and individual-residence for population-based estimates) made some group-specific estimates from the two surveillance systems more predictive of one another. Conclusion It is likely that where ANC coverage and contraceptive use is widespread and fertility is low, population-based surveillance under-estimates HIV prevalence due to unrepresentative testing by age, residence and also probably by HIV status, and that ANC sentinel surveillance over-estimates prevalence due to

  14. Decoupling of soil C and N mineralization by labile C inputs explain high C sequestration rates in response to N fertilization

    Science.gov (United States)

    Bengtson, Per; Ehtesham, Emad

    2015-04-01

    , possibly because of preferential glucose use by the microbial community. The decoupling was most pronounced in the N-fertilized plot with high tree density, where an up to 30 percent decrease in microbial respiration of SOM coincided with a more than 7-fold increase in gross N mineralization. A PLSR-analysis of 13C incorporation into microbial biomarker lipids (PLFA's) suggest that fungi was mediating this response, since the proportion of glucose derived 13C that was recovered in the fungal biomarker PLFA 18:2ω6,9 was negatively correlated to respiration of SOM and C priming, and positively to gross N mineralization and N priming. The results suggest that labile C inputs can contribute to C sequestration above as well as below ground, since microbial immobilization of the labile C may result in decreased microbial respiration of SOM that coincides with a strong increase in the production of plant available N. Tree density and N fertilization appear to be important mediators of the response, which could potentially explain the strong effect of N fertilization on net ecosystem exchange that have previously been reported.

  15. Primary immunodeficiencies in highly consanguineous North African populations.

    Science.gov (United States)

    Barbouche, Mohamed-Ridha; Galal, Nermeen; Ben-Mustapha, Imen; Jeddane, Leïla; Mellouli, Fethi; Ailal, Fatima; Bejaoui, Mohamed; Boutros, Jeanette; Marsafy, Aisha; Bousfiha, Ahmed Aziz

    2011-11-01

    The study of inbred populations has contributed remarkably to the description of new autosomal recessive primary immunodeficiencies (PIDs). Here, we examine the pattern of PIDs in North African populations and assess the impact of highly prevalent consanguinity. This review reports on the current status of pediatricians' awareness of PIDs in Egypt, Morocco, and Tunisia, where awareness of PIDs is relatively recent. The phenotypic distribution of PIDs is reported and compared among the three countries and with other populations. Data analysis reveals a prevalence of autosomal recessive forms and a peculiar distribution of major PID categories, particularly more combined immunodeficiencies than antibody disorders. In these endogamous communities, molecular diagnosis is critical to developing a genetic-based preventive approach. The organization of diagnosis and care services in these resource-limited settings faces many obstacles. Autosomal recessive PIDs are overrepresented; thus, it is critical to continue investigation of these diseases in order to better understand the underlying mechanisms and to improve patient care. © 2011 New York Academy of Sciences.

  16. Intergenerational fertility among Hispanic women: new evidence of immigrant assimilation.

    Science.gov (United States)

    Parrado, Emilio A; Morgan, S Philip

    2008-08-01

    In recent decades, rapid growth of the U.S. Hispanic population has raised concerns about immigrant adaptation, including fertility. Empirical research suggests that Hispanics, especially Mexicans, might not be following the historical European pattern of rapid intergenerational fertility decline (and convergence toward native levels). If confirmed, continued high Hispanic fertility could indicate a broader lack of assimilation into mainstream American society. In this paper, we reexamine the issue of Hispanic and Mexican fertility using an approach that combines biological and immigrant generations to more closely approximate a comparison of immigrant women with those of their daughters' and granddaughters' generation. Contrary to cross-sectional results, our new analyses show that Hispanic and Mexican fertility is converging with that of whites, and that it is similarly responsive to period conditions and to women's level of education. In addition, we employ a mathematical simulation to illustrate the conditions under which cross-sectional analyses can produce misleading results. Finally, we discuss the import of the fertility convergence we document for debates about immigrant assimilation.

  17. Men's knowledge of their own fertility: a population-based survey examining the awareness of factors that are associated with male infertility.

    Science.gov (United States)

    Daumler, D; Chan, P; Lo, K C; Takefman, J; Zelkowitz, P

    2016-12-01

    How knowledgeable are men about the medical, environmental and psychological factors that are associated with male infertility? Men, across most demographic groups, have limited knowledge of the various factors that are associated with male infertility. Few surveys have focused on men's knowledge of their own fertility. Studies of both men and women have found that men are comparatively less knowledgeable about issues of fertility and reproductive health. A regionally representative sample of Canadian men completed a web-based survey of male fertility and reproductive health, over a 2-month period in 2015. Men, aged 18-50 years, were recruited for the study. There were 701 male participants, with a mean age of 34.1 years. Each participant was asked to identify factors associated with male infertility; fertility knowledge was assessed through two open-ended questions and a comprehensive list of risk factors and attendant health issues. Men were only able to identify 51% of the risk factors and 45% of the health issues associated with male infertility. Men were most aware of the modifiable risk factors for infertility (e.g. sexually transmitted infections, smoking cigarettes), relative to their knowledge of fixed risk factors (e.g. delayed puberty, size of testicles) and the attendant health issues (e.g. cardiovascular disease, diabetes). The overall level of fertility knowledge did not vary by most demographic characteristics (e.g. age, education, employment, income), though men from ethnic minority groups displayed moderately greater awareness. Additionally, younger men, those with lower incomes and those who had no desire to have future biological children were more likely to identify themselves as unaware of associations with infertility in the open-ended questions. Self-reported knowledge was significantly associated with higher overall knowledge scores. More than half of the sample expressed an interest in obtaining information about male fertility and

  18. Determination of plant hormones in fertilizers by high-performance liquid chromatography with photodiode array detection: method development and single-laboratory validation.

    Science.gov (United States)

    Gambino, Grazia Laura; Pagano, Pietro; Scordino, Monica; Sabatino, Leonardo; Scollo, Emanuele; Traulo, Pasqualino; Gagliano, Giacomo

    2008-01-01

    A simple and reliable high-performance liquid chromatographic method that uses photodiode array detection was developed for the simultaneous determination of 12 native and synthetic plant hormones, i.e., plant growth regulators (PGRs), in fertilizers, such as 1-naphthol, 2,4-dichlorophenoxyacetic acid, 4-(2,4-dichlorophenoxy)butyric acid, 4-chlorophenoxyacetic acid, indole-3-acetic acid, 4-(3-indolyl)butyric acid, dichlorprop, (4-chloro-2-methylphenoxy)acetic acid, alpha-naphthaleneacetic acid, 1-naphthaleneacetamide, beta-naphthoxyacetic acid, and thidiazuron. The method was experimentally validated for routine regulatory application, and the following analytical parameters were assessed for all PGRs studied: linearity; specificity; precision (relative standard deviation) and accuracy, both measured at 3 concentration levels (0.1, 0.05, and 0.01%, w/w); ruggedness; limit of detection; and limit of quantification. Results were satisfactory for all method validation parameters tested and for all PGRs studied, demonstrating the suitability of the method for the determination of PGRs in fertilizers. The uncertainty of measurement was also estimated at 3 concentration levels for all PGRs by using the approach of the International Organization for Standardization, described in its Guide to the Expression of Uncertainty in Measurement. The method was applied to 20 samples of liquid fertilizer with declared biostimulant properties.

  19. Effects of Controlled-Release Fertilizer on Leaf Area Index and Fruit Yield in High-Density Soilless Tomato Culture Using Low Node-Order Pinching

    Science.gov (United States)

    Kinoshita, Takafumi; Yano, Takayoshi; Sugiura, Makoto; Nagasaki, Yuji

    2014-01-01

    To further development of a simplified fertigation system using controlled-release fertilizers (CRF), we investigated the effects of differing levels of fertilizers and plant density on leaf area index (LAI), fruit yields, and nutrient use in soilless tomato cultures with low node-order pinching and high plant density during spring-summer (SS), summer-fall (SF), and fall-winter (FW) seasons. Plants were treated with 1 of 3 levels of CRF in a closed system, or with liquid fertilizer (LF) with constant electrical conductivity (EC) in a drip-draining system. Two plant densities were examined for each fertilizer treatment. In CRF treatments, LAI at pinching increased linearly with increasing nutrient supply for all cropping seasons. In SS, both light interception by plant canopy at pinching and total marketable fruit yield increased linearly with increasing LAI up to 6 m2·m−2; the maximization point was not reached for any of the treatments. In FW, both light interception and yield were maximized at an LAI of approximately 4. These results suggest that maximizing the LAI in SS and FW to the saturation point for light interception is important for increasing yield. In SF, however, the yield maximized at an LAI of approximately 3, although the light interception linearly increased with increasing LAI, up to 4.5. According to our results, the optimal LAI at pinching may be 6 in SS, 3 in SF, and 4 in FW. In comparing LAI values with similar fruit yield, we found that nutrient supply was 32−46% lower with the CRF method than with LF. In conclusion, CRF application in a closed system enables growers to achieve a desirable LAI to maximize fruit yield with a regulated amount of nutrient supply per unit area. Further, the CRF method greatly reduced nutrient use without decreasing fruit yield at similar LAIs, as compared to the LF method. PMID:25402478

  20. Effects of controlled-release fertilizer on leaf area index and fruit yield in high-density soilless tomato culture using low node-order pinching.

    Directory of Open Access Journals (Sweden)

    Takafumi Kinoshita

    Full Text Available To further development of a simplified fertigation system using controlled-release fertilizers (CRF, we investigated the effects of differing levels of fertilizers and plant density on leaf area index (LAI, fruit yields, and nutrient use in soilless tomato cultures with low node-order pinching and high plant density during spring-summer (SS, summer-fall (SF, and fall-winter (FW seasons. Plants were treated with 1 of 3 levels of CRF in a closed system, or with liquid fertilizer (LF with constant electrical conductivity (EC in a drip-draining system. Two plant densities were examined for each fertilizer treatment. In CRF treatments, LAI at pinching increased linearly with increasing nutrient supply for all cropping seasons. In SS, both light interception by plant canopy at pinching and total marketable fruit yield increased linearly with increasing LAI up to 6 m(2 · m(-2; the maximization point was not reached for any of the treatments. In FW, both light interception and yield were maximized at an LAI of approximately 4. These results suggest that maximizing the LAI in SS and FW to the saturation point for light interception is important for increasing yield. In SF, however, the yield maximized at an LAI of approximately 3, although the light interception linearly increased with increasing LAI, up to 4.5. According to our results, the optimal LAI at pinching may be 6 in SS, 3 in SF, and 4 in FW. In comparing LAI values with similar fruit yield, we found that nutrient supply was 32-46% lower with the CRF method than with LF. In conclusion, CRF application in a closed system enables growers to achieve a desirable LAI to maximize fruit yield with a regulated amount of nutrient supply per unit area. Further, the CRF method greatly reduced nutrient use without decreasing fruit yield at similar LAIs, as compared to the LF method.

  1. Stellar Population Maps of High-Redshift Galaxies

    Science.gov (United States)

    Fetherolf, Tara; Reddy, Naveen; MOSDEF

    2016-06-01

    A comprehensive study of resolved galaxy structure can shed light on the formation and evolution of galactic properties, such as the distribution of stars and interstellar dust that obscures starlight. This requires high-resolution, multi-waveband photometry and spectroscopy to completely characterize the galaxies. Previous studies lacked key spectroscopic information, were comprised of small samples, or focused on the local universe. We use HST ACS/WFC3 high-resolution, multi-waveband imaging from the CANDELS project in parallel with moderate-resolution Keck I MOSFIRE spectra from the MOSFIRE Deep Evolution Field (MOSDEF) survey to produce resolved stellar population and dust maps of ~500 galaxies at redshifts 1.4 < z < 2.6—covering the key epoch when galaxies accreted most of their mass. For data preparation and analysis we develop an automated Python program to process our large, comprehensive dataset. From the multi-waveband imaging and spectroscopic redshifts, we model the spectral energy distribution for every resolution element within each galaxy and compare these results to the spectroscopically measured global properties. From our stellar population and dust maps we identify resolved structures within these galaxies. We also investigate if spectroscopically measured galaxy properties are biased when compared with that of localized sub-galactic structures.

  2. Improved fertility following conservative surgical treatment of ectopic pregnancy

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Lund, Claus Otto; Ottesen, Bent

    2003-01-01

    OBJECTIVE: To evaluate fertility after salpingectomy or tubotomy for ectopic pregnancy. DESIGN: Retrospective cohort study. SETTING: Clinical University Center, Hvidovre Hospital, Copenhagen. POPULATION: Two hundred and seventy-six women undergoing salpingectomy or tubotomy for their first ectopic...... intrauterine pregnancy rate was significantly higher after tubotomy (88%) than after salpingectomy (66%) (log rank P treatments (16% vs 17%). In patients with contralateral tubal...... pathology, the chance of pregnancy was poor (hazard ratio 0.463) and the risk of recurrence was high (hazard ratio 2.25), assessed with Cox regression. The rate of persistent ectopic pregnancy was 8%. CONCLUSION: Conservative surgery is superior to radical surgery at preserving fertility. Conservative...

  3. What Is Fertility Preservation?

    Science.gov (United States)

    ... Share Facebook Twitter Pinterest Email Print What is fertility preservation? Fertility preservation is the process of saving or protecting ... children in the future. Who can benefit from fertility preservation? People with certain diseases, disorders, and life ...

  4. Fertility Clinic Success Rates

    Science.gov (United States)

    ... Defects ART and Autism 2013 Assisted Reproductive Technology Fertility Clinic Success Rates Report Recommend on Facebook Tweet ... Additional Information About ART in the United States. Fertility Clinic Tables Introduction to Fertility Clinic Tables [PDF - ...

  5. The Potential Impact of Changes in Fertility on Infant, Child, and Maternal Mortality. World Bank Staff Working Papers No. 698 and Population and Development Series No. 23.

    Science.gov (United States)

    Trussell, James; Pebley, Anne R.

    The relationship between changes in the timing and quantity of fertility, such as those that might result from an effective family planning program in developing countries, and changes in child and maternal mortality is examined. Results from five multivariate studies estimate the changes in mortality that might occur from altering maternal age,…

  6. Fertility Herbs: Do They Enhance Fertility?

    Science.gov (United States)

    ... get pregnant. I've seen many ads for fertility herbs and supplements. Do they work? Answers from ... for infertility. Unfortunately, the research on so-called fertility herbs and supplements is inconclusive and based on ...

  7. Reducing fertilization for cut roses: effect on crop productivity and twospotted spider mite abundance, distribution, and management.

    Science.gov (United States)

    Chow, Andrew; Chau, Amanda; Heinz, Kevin M

    2009-10-01

    Fertilization reduction could be a useful pest management tactic for floriculture crops if it reduced pest populations with little loss in crop yield and quality. We evaluated the response of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), to different fertilization levels for cut roses, Rosa hybrida L. 'Tropicana' and quantified fertilization effects on (1) management of T. urticae on roses, (2) abundance and distribution of T. urticae on roses, and (3) yield and quality of the cut rose crop. We tested two fertilization levels, 10% (15 ppm N) and 100% (150 ppm N) of the recommended level for commercial production, and three control methods: no control measure; a predatory mite, Phytoseiulus persimilis Athias-Henriot; and a miticide, bifenazate. Combinations of both bottom up (fertilization) and top down (biological or chemical control) tactics provided a greater degree of T. urticae control than either tactic alone. Rose productivity was reduced with fertilization at 10% of the recommended level; therefore, we conducted studies with T. urticae on roses fertilized with 33% (50 ppm N), 50% (75 ppm N), and 100% (150 ppm N) of the recommended level. Mean numbers of T. urticae and T. urticae eggs per flower shoot were twice as high on roses fertilized with 100 versus 33% or 50% of the recommended level. Number of rose leaves and total leaf area infested by T. urticae were similar at all fertilization levels. Cut rose yield and marketability were not compromised on plants fertilized with 50% of the recommended level.

  8. Infertility Treatment and Fertility-Specific Distress: A Longitudinal Analysis of a Population-Based Sample of U.S. Women

    Science.gov (United States)

    Greil, Arthur L.; McQuillan, Julia; Lowry, Michele; Shreffler, Karina M.

    2011-01-01

    Because research on infertile women usually uses clinic-based samples of treatment seekers, it is difficult to sort out to what extent distress is the result of the condition of infertility itself and to what extent it is a consequence of the experience of infertility treatment. We use the National Survey of Fertility Barriers, a two-wave national probability sample of U.S. women, to disentangle the effects of infertility and infertility treatment on fertility-specific distress. Using a series of ANOVAs, we examine 266 infertile women who experienced infertility both at Wave 1 and at Wave 2, three years later. We compare eight groups of infertile women based on whether or not they have received treatment and on whether or not they have had a live birth. At Wave 1, infertile women who did not receive treatment and who had no live birth reported lower distress levels than women who received treatment at Wave 1 only, regardless of whether their infertility episode was followed by a live birth. At Wave 2, women who received no treatment have significantly lower fertility-specific distress than women who were treated at Wave 1 or at Waves 1 and 2, regardless of whether there was a subsequent live birth. Furthermore, fertility-specific distress did not increase over time among infertile women who did not receive treatment. The increase in fertility-specific distress was significantly higher for women who received treatment at Wave 2 that was not followed by a live birth than for women who received no treatment or for women who received treatment at Wave 1 only. These patterns suggest that infertility treatment is associated with levels of distress over and above those associated with the state of being infertile in and of itself. PMID:21645954

  9. Anisometropia prevalence in a highly astigmatic school-aged population.

    Science.gov (United States)

    Dobson, Velma; Harvey, Erin M; Miller, Joseph M; Clifford-Donaldson, Candice E

    2008-07-01

    To describe prevalence of anisometropia, defined in terms of both sphere and cylinder, examined cross-sectionally, in school-aged members of a Native American tribe with a high prevalence of astigmatism. Cycloplegic autorefraction measurements, confirmed by retinoscopy and, when possible, by subjective refraction were obtained from 1041 Tohono O'odham children, 4 to 13 years of age. Astigmatism > or =1.00 diopter (D) was present in one or both eyes of 462 children (44.4%). Anisometropia > or =1.00 D spherical equivalent (SE) was found in 70 children (6.7%), and anisometropia > or =1.00 D cylinder was found in 156 children (15.0%). Prevalence of anisometropia did not vary significantly with age or gender. Overall prevalence of significant anisometropia was 18.1% for a difference between eyes > or =1.00 D SE or cylinder. Vector analysis of between-eye differences showed a prevalence of significant anisometropia of 25.3% for one type of vector notation (difference between eyes > or =1.00 D for M and/or > or =0.50 D for J0 or J45), and 16.2% for a second type of vector notation (between-eye vector dioptric difference > or =1.41). Prevalence of SE anisometropia is similar to that reported for other school-aged populations. However, prevalence of astigmatic anisometropia is higher than that reported for other school-aged populations.

  10. Carotid stenosis: what is the high-risk population?

    Directory of Open Access Journals (Sweden)

    Jong Hun Park

    Full Text Available OBJECTIVE: Prevention is the best treatment for cerebrovascular disease, which is why early diagnosis and the immediate treatment of carotid stenosis contribute significantly to reducing the incidence of stroke. Given its silent nature, 80% of stroke cases occur in asymptomatic individuals, emphasizing the importance of screening individuals with carotid stenosis and identifying high-risk groups for the disease. The aim of this study was to determine the prevalence and the most frequent risk factors for carotid stenosis. METHODS: A transversal study was conducted in the form of a stroke prevention campaign held on three nonconsecutive Saturdays. During the sessions, carotid stenosis diagnostic procedures were performed for 500 individuals aged 60 years or older who had systemic arterial hypertension and/or diabetes mellitus and/or coronary heart disease and/or a family history of stroke. RESULTS: The prevalence of carotid stenosis in the population studied was 7.4%, and the most frequent risk factors identified were mean age of 70 years, carotid bruit, peripheral obstructive arterial disease, coronary insufficiency and smoking. Independent predictive factors of carotid stenosis include the presence of carotid bruit or peripheral obstructive heart disease and/or coronary insufficiency. CONCLUSIONS: The population with peripheral obstructive heart disease and carotid bruit should undergo routine screening for carotid stenosis.

  11. Screening for Pompe disease in a Portuguese high risk population.

    Science.gov (United States)

    Almeida, Vânia; Conceição, Isabel; Fineza, Isabel; Coelho, Teresa; Silveira, Fernando; Santos, Manuela; Valverde, Ana; Geraldo, Argemiro; Maré, Ricardo; Aguiar, Teresa Carolina; Mendonça, Carla; Martins, João; Medeiros, Luísa; Barroso, Cândida; Vieira, José Pedro; Moreno, Teresa; Negrão, Luis; Dias, Margarida Silva; Lacerda, Lúcia; Evangelista, Teresinha

    2017-08-01

    Pompe disease is a rare metabolic disorder with available enzymatic replacement therapy. Contrasting with the classic infantile form, the others subtypes have a heterogeneous presentation that makes an early and accurate diagnosis difficult. We conducted a prospective, multicenter, observational study to identify undiagnosed patients. During a one-year period, patients followed in Portuguese neuromuscular outpatient clinics with proximal muscle weakness affecting upper and/or lower limbs, hyperCKemia in two or more determinations or hypotonia and hyperCKemia, were screened for acid α-glucosidase deficiency by dried blood spots. Lysosomal acid-alpha-1,4-glucosidase activity was determined by tandem mass spectrometry and positive results were confirmed by molecular study. From the 99 patients screened, Pompe disease was confirmed in 4, with age of onset ranging from 2.5 to 48 years, all with limb girdle muscle weakness, corresponding to a frequency of 4% in our cohort and 4.9% of limb girdle muscle weakness. Screening for Pompe disease in high risk populations, using dried blood spots, was already performed in some European populations. Apart from two negative Scandinavian studies, positive cases were confirmed in 2.8-7.9% of patients presenting with limb girdle muscle weakness and in 0-2.5% with isolated hyperCKemia. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. PHOSPHATE AND POTASSIUM FERTILIZATION FOR RADISH GROWN IN A LATOSOL WITH A HIGH CONTENT OF THESE NUTRIENTS

    OpenAIRE

    ARTHUR BERNARDES CECÍLIO FILHO; ALEXSON FILGUEIRAS DUTRA; GILSON SILVERIO DA SILVA

    2017-01-01

    The intensive cultivation of vegetables with frequent chemical fertilization may cause accumulation of nutrients in the soil. This, in turn, may reduce crop yields and damage the environment due to contamination of ground water and rivers. Thus, to increase the effects of P (0, 100, 200, 300 and 400 kg ha - 1 of P 2 O 5 ) and K (0, 60, 120, 180 and 240 kg ha - 1 of K 2 O) doses on the growth and productivity of radish cultivars (Sakata 19 and Sakata 25) in a s...

  13. Nitrogen mineralization and nitrification in a mixed-conifer forest in southern California : controlling factors, fluxes, and nitrogen fertilization response at a high and low nitrogen deposition site

    Energy Technology Data Exchange (ETDEWEB)

    Fenn, M.E.; Poth, M.A.; Terry, J.D.; Blubaugh, T.J. [United States Dept. of Agriculture, Riverside, CA (United States). Forest Service, Pacific Southwest Research Station

    2005-06-01

    Human activities and anthropogenic emissions have disturbed the global nitrogen (N) cycle to the point that atmospheric deposition of inorganic nitrogen has increased nearly threefold above preindustrial levels. These increased levels have the potential to cause excessive nitrogen enrichment of aquatic and terrestrial ecosystems. Increased nitrogen levels stimulate nitrogen mineralization and nitrification, thereby contributing to mobilization of nitrogen and nitrogen saturation conditions. In this study, net fluxes of nitrogen mineralization and nitrification were measured in situ on a monthly basis for 3 years in the San Bernardino Mountains in California. The objective was to quantify the rates of net nitrogen mineralization and nitrification in the humus layer and mineral soil under field conditions in fertilized and unfertilized plots at a nitrogen deposition forest site that is highly N saturated as well as a low nitrogen deposition site to determine whether relative nitrification patterns in field assays are similar to laboratory study results. The main factors affecting nitrogen cycling rates in the mineral soil and the forest floor were determined. The study also tested the hypothesis that slow release nitrogen fertilization over 3 years at a low nitrogen site results in net nitrification rates that approach those of high nitrogen sites. The study revealed the relative nitrification rates under different tree canopies. The key factor for predicting the rate of net nitrification is the rate of net nitrogen mineralization. A high nitrogen fertilization had no substantial impact on net nitrification. It was concluded that at low-deposition sites, increased nitrification occurs in the short term due to added nitrogen. However, the accumulation of nitrogen enriched litter and soil organic matter along with chronic throughfall nitrogen deposition causes sustained elevated net nitrification. 67 refs., 7 tabs., 7 figs.

  14. TOB-G: Tobacco Cessation Guidelines for High risk Populations

    Directory of Open Access Journals (Sweden)

    Panagiotis Behrakis

    2016-03-01

    Full Text Available The TOB-G project is funded under the EU 3rd Health Programme which is the main instrument that the Commission uses to implement the EU Health Strategy. The project started in June 2014 and will be completed in September 2017. The project consortium consists of 5 partners from 4 European countries (Belgium, Greece, Ireland and Romania. The TOB-G project aims to develop and implement an innovative and cost effective approach to prevent chronic diseases related to tobacco dependence by focusing on creating specialized tobacco cessation guidelines for populations of high risk including adolescents, pregnant women, adults with COPD, Cardiovascular disease and diabetes. The specialized guidelines for high risks groups will be developed according to ENSP’s evidence based and good practices in tobacco cessation. The smoking cessation guidelines contain strategies and recommendations designed to assist clinicians/ doctors in delivering and supporting effective treatments for tobacco use and dependence and will also be available within the context of an e-learning platform for European clinicians. Overall, the TOB-G project will enhance the overall European capacity in the treatment of tobacco dependence, through offering smoking cessation tools, appropriately assessed and fitted to the specific needs of high risk groups.

  15. Slow-Release Fertilizer

    Science.gov (United States)

    1998-01-01

    Under an SBIR (Small Business Innovative Research), ZeoponiX, Inc., introduced ZeoPro. This product is used as a fertilizer/soil amendment for golf courses, ball fields, greenhouse and horticultural uses. A combination of superior growth medium and soil conditioner allow for nutrient supplementation and high efficiency delivery of nutrients throughout the plant. ZeoPro provides a balanced nutrient system for major, minor, and trace nutrients.

  16. ASSESSMENT OF ORGANIC FERTILIZER USAGE BY VEGETABLE ...

    African Journals Online (AJOL)

    IBUKUN

    ABSTRACT. Vegetables support rural and urban population both in terms of subsistence and income generation. Its cultivation however presents with problems that can be reduced with the use of organic fertilizers. Therefore, there is a need to assess the use of organic fertilizer among vegetable growers as it directly affects ...

  17. Differentials of fertility in Rural Butajira

    African Journals Online (AJOL)

    Background: Ethiopia is one of the populous countries in Africa. Only about 8 % of currently married women are using contraception, which is low to affect the fertility level significantly. Objectives: To identify differentials of fertility in Rural Butajira, Meskan and Mareko District of. Southern Nations', Nationalities and Peoples ...

  18. Effect of Fertilizer Type and Method of Application on Nutrient ...

    African Journals Online (AJOL)

    The effects of fertilizer types and methods of application on the nutritive value and in situ rumen degradability of maize straw were assessed. The fertilizer types were; Low analysis fertilizer (LAF), with nutrient contents of less than 41% and High analysis fertilizer (HAF), with nutrient contents greater than 41%. The methods of ...

  19. Philippine population trends.

    Science.gov (United States)

    1984-01-01

    This paper presents an overview of Philippine population trends and prospects. The population growth rate, which has been 2% in this century, is declining in most regions of the Philippines. The 1980 census showed a decline in the proportion of the population under 15 uears old. The size of the working-age population and the aged rose slightly. The median age in 1980 was 18.6 years as opposed to 16.9 years in 1970. Men still outnumber women in the Philippines. Urbanization has increased by 10% from 1948 to 1980, a relatively sluggish urban growth rate. In 1960, the total fertility rate was 6.5; this declined to 5.2 in 1975. The regions that are most exposed to modernization have the lowest fertility. Philippine surveys show that urban population (especially metro Manilans), the college educated, and those married to white collar workers have the smallest family size. Age at marriage also influences fertility. Mortality has declined continuously during the 20th century, and especially from 1968-1980. The 1980 census shows a higher population growth rate than expected. This makes replacement level fertility unlikely by the end of the century. Projections demonstrate that the population size of the country will be at least 71 million and perhaps as much as 80 million by the end of the century. These population figures highlight the following development issues: 1) an increasing number of jobs for the growing numbers of people in the working ages, 15-64; 2) lower productivity due to large numbers of young inexperienced workers; 3) larger numbers of retired people in relation to workers; 4) an imbalance in educational opportunities and health care between rural and urban areas; 5) the inability of the family planning program to reach high fertility sub-groups; 6) the need for rural development programs; and 7) the increasing interrelationship between demographic and development trends.

  20. Communication and coping as predictors of fertility problem stress: cohort study of 816 participants who did not achieve a delivery after 12 months of fertility treatment.

    Science.gov (United States)

    Schmidt, L; Holstein, B E; Christensen, U; Boivin, J

    2005-11-01

    We investigated coping strategies and communication strategies as predictors of fertility problem stress 12 months after start of fertility treatment. We used a prospective, longitudinal cohort design including 2250 people beginning fertility treatment with a 12-month follow-up. Data were based on self-administered questionnaires measuring communication with partner and with other people, coping strategies: active-avoidance coping, active-confronting coping, passive-avoidance coping, meaning-based coping, and fertility problem stress. The study population included those participants (n = 816, men and women) who had not achieved pregnancy by assisted reproduction or delivery at follow-up. Among both men and women, difficulties in partner communication predicted high fertility problem stress (odds ratio for women, 3.47, 95% confidence interval 2.09-5.76; odds ratio for men, 3.69, 95% confidence interval 2.09-6.43). Active-avoidance coping (e.g. avoiding being with pregnant women or children, turning to work to take their mind off things) was a significant predictor of high fertility problem stress. Among men, high use of active-confronting coping (e.g. letting feelings out, asking other people for advice, seeking social support) predicted low fertility problem stress in the marital domain (odds ratio 0.53, 95% confidence interval 0.28-1.00). Among women, medium or high use of meaning-based coping significantly predicted low fertility problem stress in the personal and marital domain. The study provides information about where to intervene with fertility patients in order to reduce their stress after medically unsuccessful treatment.

  1. Fertile changes.

    Science.gov (United States)

    Cherkaoui, M

    1995-01-01

    In Morocco, fertility levels have dropped in the past 30 years, and women have found that freedom from perpetual child-bearing has allowed them to make various contributions to society. One of the first Moroccan women elected to parliament noted that family planning best succeeds when it is the result of informed, personal choice enabled by education. A woman who is a prominent journalist noted that the availability of oral contraceptives has contributed to the emancipation of Moroccan women. A female television personality decried currently available television health messages, yet found cause for optimism in the receptiveness of Moroccan society to properly presented television messages. A woman who is a singer as well as a clinical psychologist found that birth control has made women more fulfilled, more independent, and has freed them of the aging which occurs with continual child-bearing. Another female journalist found that the Moroccan women who have been able to overcome social pressure to view themselves primarily as child-bearers attribute the advent of birth control to their liberation. Not only can they pursue careers, they can expend more energy on each of their children and assume equal position with the men in their lives. Finally, a female film maker asserted that birth control has enhanced life for women, who now have choices; children, who benefit from being wanted; and men, who are relieved of the burden of providing for large families.

  2. High frequency of extra-pair paternity in an urban population of Cooper's Hawks

    Science.gov (United States)

    Rosenfield, Robert N.; Sonsthagen, Sarah A.; Stout, William C.; Talbot, Sandra

    2015-01-01

    Raptors exhibit some of the highest rates of intra-pair copulations among birds, perhaps in an attempt by males to reduce the risk of being cuckolded. Indeed, the frequency of extra-pair fertilizations reported in studies of raptors to date is relatively low (0-11.2%). Socially monogamous Cooper's Hawks (Accipiter cooperii) exhibit one of the highest copulation rates among birds, yet there are no published accounts of extra-pair copulations (or paternity). We studied a population of Cooper's Hawks in Milwaukee, Wisconsin, during three breeding seasons (2003, 2004, and 2007), examining the possible effects of age (1 yr old vs. ≥ 2 yr old), adult mass, and brood size on the frequency of extra-pair paternity (EPP). We found that 19.3% of nestlings (N = 27/140) were extra-pair young (EPY), and 34% of all broods (N = 15/44) had at least one EPY. The sires of the EPY in our study were identified for only two broods, suggesting that floater males may have engaged in extra-pair copulations with territorial females. We found that brood size was a good predictor of the occurrence of EPP (EPP) in nests, but adult mass and female age were not. To our knowledge, these possible correlates of the occurrence of EPP in raptors had not previously been investigated. Male Cooper's Hawks provide food for females during the pre-nesting period, and delivery of food is, in contrast to other raptor species, typically followed by copulation. Thus, one possible explanation of the relatively high rates of EPP in our study is that females might accept or even solicit extra-pair copulations from males other than their mates as a means of maximizing energy intake for egg production. Such behavior might be particularly likely in our study area, i.e., a food-rich urban setting with a high breeding density of Cooper's Hawks.

  3. Impact of consanguinity on cancer in a highly endogamous population.

    Science.gov (United States)

    Bener, Abdulbari; El Ayoubi, Hanadi R; Chouchane, Lotfi; Ali, Awab I; Al-Kubaisi, Aisha; Al-Sulaiti, Haya; Teebi, Ahmad S

    2009-01-01

    Many epidemiological studies have indicated that inbreeding has little or no effect on the incidence of cancer. Due to the high prevalence of consanguinity in Qatar (54%), its influence may nevertheless be of special importance. The aim of this study was to examine whether parental consanguinity affects the risk of cancer in a local Arab highly inbred population. Matched case-control study. The study was carried out in Al-Amal cancer hospital and primary health care centers in Qatar over a period from August 2008 to February 2009. The study included 370 Qataris and other Arab expatriates with various types of cancers and 635 controls matched by age and ethnicity. A questionnaire that included socio-demographic information, type of consanguinity, medical history, and tumor grade was designed to collect the information of cases and controls. The study revealed that the rate of parental consanguinity was similar in both cases (29.5%) and controls (29.9%) with a higher inbreeding coefficient in controls (0.017-/+0.03), compared to cancer patients (0.0155-/+0.03). Other Arab expatriates had a higher incidence of cancer (61.1%) than Qataris (38.9%). The inbreeding coefficient was higher in male cancer patients (0.0189-/+0.03), but lower in female cancer patients (0.014-/+0.03) as compared to controls. Controls were more inbred in the overall studied subjects (23.6%) and women (23.8%) than cases. The coefficient of inbreeding was lower in patients with breast (0.014), skin (0.012), thyroid (0.008) and female genital (0.014) cancers, whereas it was higher in cases for leukemia and lymphoma (0.018), colorectal (0.025) and prostate (0.017), with no significant difference between cases and controls. No significant differences were observed between cases and controls in the parental consanguinity, mean coefficient of inbreeding and proportion of more inbred subjects. The study findings revealed that although the consanguinity rate is high in our Arab population, it has no

  4. Effects of fertility education on knowledge, desires and anxiety among the reproductive-aged population: findings from a randomized controlled trial.

    Science.gov (United States)

    Maeda, E; Nakamura, F; Kobayashi, Y; Boivin, J; Sugimori, H; Murata, K; Saito, H

    2016-09-01

    What are the effects of fertility education on knowledge, childbearing desires and anxiety? Providing fertility information contributed to greater knowledge, but increased anxiety. Past studies have found that exposure to educational material improved fertility awareness and changed desires toward childbearing and its timing. Existing educational websites with evidence-based medical information provided in a non-judgmental manner have received favorable responses from reproductive-aged men and women. This three-armed (one intervention and two control groups), randomized controlled trial was conducted using online social research panels (SRPs) in Japan in January 2015. A total of 1455 participants (726 men and 729 women) between 20 and 39 years of age who hoped to have (more) children in the future were block-randomized and exposed to one of three information brochures: fertility education (intervention group), intake of folic acid during pregnancy (control group 1) or governmental financial support for pregnancy and childbirth (control group 2). Fertility knowledge was measured with the Japanese version of the Cardiff Fertility Knowledge Scale (CFKS-J). Knowledge, child-number and child-timing desires, subjective anxiety (i.e. whether participants felt anxiety [primary outcome]), and scores on the State-Trait Anxiety Inventory were assessed immediately after exposure. Non-inferiority comparisons were performed on subjective anxiety with non-inferiority declared if the upper limit of the two-sided 95% confidence interval (CI) for risk difference did not exceed a margin of 0.15. This test for non-inferiority was only performed for subjective anxiety; all the other variables were tests of superiority. Posttest scores on the CFKS-J (mean, SD) were higher in the intervention group than that of the control groups: intervention versus Control 1 and versus Control 2: 52.8 (28.8) versus 40.9 (26.2) (Panxiety after exposure to the intervention brochure was significantly

  5. Nutritional status, fertility and factors associated with anaemia: a cross sectional study among a rural population of Muslim women in Assam, India.

    Science.gov (United States)

    Haloi, Anjali; Limbu, Dhruba Kumar

    2013-01-01

    In the present study an attempt has been made to report on the nutritional status of the Assamese Muslim women of Dadara and Agyathuri villages of the Kamrup district in Assam, India on their basis of body mass index (BMI) and haemoglobin (hb) content. Cross sectional data on 1034 women belonging to the age group of 19 years and above were collected following internationally accepted standards. The fertility of mothers by BMI range was found to be highest (6.50 (mean) +/- 0.14 (SE) and range being 1-11) amongst underweight mothers. The one-way analysis of variance (ANOVA) test of BMI and fertility shows significant relation between different BMI groups withp nutritional status. These findings might be important in formulating responsive health policies in an underdeveloped region.

  6. Population policies and development.

    Science.gov (United States)

    Stamper, B M

    1984-01-01

    This article critically examines 4 conceptual frameworks for Third World population policies: the family planning approach, beyond family planning measures, the development hypothesis and transition theory, and the distributive hypothesis and fertility. Although family planning is a basic human right and can lead to lower levels of population and improved maternal-child health, this approach alone does not always have a meaningful demographic impact. If high fertility is economically rational from the family viewpoint, the demand for family planning services will remain marginal. Other policies seek to go beyond the family planning approach and to directly influence the demand for reproductive control through provision of old age support, monetary incentives for reduced fertility or stringent and coercive measures. However, such policies can have adverse distributional effects and directly penalize the children of large families. The demographic transition theory lacks a measurable and specifiable causation mechanism, giving it little predictive value. It may be that economic growth increases fertility in the short run and reduces fertility only over the long run through indirect effects. The key issue is how the rate of growth is distributed across the population. The development and demographic transition hypothesis focuses mainly on aggregate economic and social measures rather than on their underlying distributions. The distributive hypothesis implies policies that promote a greater level of investment in human capital, with a wide distributional emphasis. Diffused investment in human capital is believed to indirectly influence the desire to control fertility. It is concluded that all 4 conceptual frameworks for analyzing fertility-related policies for the Third World are inadequate or seriously flawed. They are not pragmatic, do not identify or assign weights to the crucial causal variables, fail to specify thresholds or critical minimum levels, discount

  7. Consanguinity and late fertility: spatial analysis reveals positive association patterns.

    Science.gov (United States)

    Lisa, Antonella; Astolfi, Paola; Zei, Gianna; Tentoni, Stefania

    2015-01-01

    The role of consanguinity on human complex traits is an important and controversial issue. In this work we focused on the Sardinian population and examined the effect of consanguineous unions on late female fertility. During the last century the island has been characterized by a high incidence of marriages between relatives, favoured by socio economic conditions and geographical isolation, and by high fertility despite a widespread tendency to delay reproduction. Through spatial analysis techniques, we explored the geographical heterogeneity of consanguinity and late fertility, and identified in Central-Eastern Sardinia a common area with an excess of both traits, where the traits are positively associated. We found that their association did not significantly affect women's fertility in the area, despite the expected negative role of both traits. Intriguingly, this critical zone corresponds well to areas reported by previous studies as being peculiar for a high frequency of centenarians and for lower risk in pregnancy outcome. The proposed approach can be generally exploited to identify target populations on which socioeconomic, biodemographic and genetic data can be collected at the individual level, and deeper analyses carried out to disentangle the determinants of complex biological traits and to investigate their association. © 2014 John Wiley & Sons Ltd/University College London.

  8. Infertility treatment and fertility-specific distress: A longitudinal analysis of a population-based sample of U.S. women.

    Science.gov (United States)

    Greil, Arthur L; McQuillan, Julia; Lowry, Michele; Shreffler, Karina M

    2011-07-01

    Because research on infertile women usually uses clinic-based samples of treatment seekers, it is difficult to sort out to what extent distress is the result of the condition of infertility itself and to what extent it is a consequence of the experience of infertility treatment. We use the National Survey of Fertility Barriers, a two-wave national probability sample of U.S. women, to disentangle the effects of infertility and infertility treatment on fertility-specific distress. Using a series of ANOVAs, we examine 266 infertile women who experienced infertility both at Wave 1 and at Wave 2, three years later. We compare eight groups of infertile women based on whether or not they have received treatment and on whether or not they have had a live birth. At Wave 1, infertile women who did not receive treatment and who had no live birth reported lower distress levels than women who received treatment at Wave 1 only, regardless of whether their infertility episode was followed by a live birth. At Wave 2, women who received no treatment have significantly lower fertility-specific distress than women who were treated at Wave 1 or at Waves 1 and 2, regardless of whether there was a subsequent live birth. Furthermore, fertility-specific distress did not increase over time among infertile women who did not receive treatment. The increase infertility-specific distress was significantly higher for women who received treatment at Wave 2 that was not followed by a live birth than for women who received no treatment or for women who received treatment at Wave 1 only. These patterns suggest that infertility treatment is associated with levels of distress over and above those associated with the state of being infertile in and of itself. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. A 660-Kb deletion with antagonistic effects on fertility and milk production segregates at high frequency in Nordic Red cattle: additional evidence for the common occurrence of balancing selection in livestock.

    OpenAIRE

    Naveen Kumar Kadri; Goutam Sahana; Carole Charlier; Terhi Iso-Touru; Bernt Guldbrandtsen; Latifa Karim; Ulrik Sander Nielsen; Frank Panitz; Gert Pedersen Aamand; Nina Schulman; Michel Georges; Johanna Vilkki; Mogens Sandø Lund; Tom Druet

    2014-01-01

    In dairy cattle, the widespread use of artificial insemination has resulted in increased selection intensity, which has led to spectacular increase in productivity. However, cow fertility has concomitantly severely declined. It is generally assumed that this reduction is primarily due to the negative energy balance of high-producing cows at the peak of lactation. We herein describe the fine-mapping of a major fertility QTL in Nordic Red cattle, and identify a 660-kb deletion encompassing four...

  10. High proportion of male faeces in jaguar populations.

    Directory of Open Access Journals (Sweden)

    Francisco Palomares

    Full Text Available Faeces provide relevant biological information which includes, with the application of genetic techniques, the sex and identity of individuals that defecated, thus providing potentially useful data on the behaviour and ecology of individuals, as well as the dynamics and structure of populations. This paper presents estimates of the sex ratio of different felid species (jaguar, Panthera onca; puma, Puma concolor; and ocelot/margay, Leopardus pardalis/Leopardus wiedi as observed in field collected faeces, and proposes several hypotheses that could explain the strikingly high proportion of faeces from male jaguars. The proportion of male and female faeces was estimated using a non-invasive faecal sampling method in 14 study areas in Mexico and Brazil. Faecal samples were genetically analysed to identify the species, the sex and the individual (the latter only for samples identified as belonging to jaguars. Considering the three species, 72.6% of faeces (n = 493 were from males; however, there were significant differences among them, with the proportion from males being higher for jaguars than for pumas and ocelots/margays. A male-bias was consistently observed in all study areas for jaguar faeces, but not for the other species. For jaguars the trend was the same when considering the number of individuals identified (n = 68, with an average of 4.2±0.56 faeces per male and 2.0±0.36 per female. The observed faecal marking patterns might be related to the behaviour of female jaguars directed toward protecting litters from males, and in both male and female pumas, to prevent interspecific aggressions from male jaguars. The hypothesis that there are effectively more males than females in jaguar populations cannot be discarded, which could be due to the fact that females are territorial and males are not, or a tendency for males to disperse into suboptimal areas for the species.

  11. Fertility trends in Singapore.

    Science.gov (United States)

    Singh, K; Viegas, O; Ratnam, S S

    1988-10-01

    In 1966, the Singapore National Family Planning and Population Program established the goal of reaching replacement fertility by 1990 and zero population growth by the year 2030. To achieve this goal, the government relied on a series of incentives and disincentives to discourage births above the 3rd birth order, including tax relief for the 1st 3 children only, paid medical leave for women undergoing sterilization after the 3rd or subsequent birth, monetary stipends in some cases where the mother is sterilized after the 1st or 2nd birth, and increasing accouchement charges for increasing birth orders. Also important to demographic planning were liberalization of Singapore's abortion legislation and more aggressive promotion of contraception. As a result of these efforts, Singapore's crude birth rate has declined from 29.5/1000 population in 1965 to 16.6/1000 in 1985. Also observed have been dramatic declines in infant mortality in this same period, from 26.2/1000 live births to 9.3/1000, and in maternal mortality, from 52/100,000 live births to 10/100,000. In 1985, 42% of total births were to women in the 25-29-year age group. The numbers of 4th and later births fell by 90% between 1966 and 1985. The total fertility rate has declined from 4.6/woman in 1965 to 3.1 in 1970 to 1.6 in 1986. Below replacement level fertility was achieved in 1975, in part because of government policy but also as a result of cultural and socioeconomic factors such as increasing female labor force participation rates, a break-up of the extended family system, a rise in the age at 1st marriage, and rises in educational attainment. The drop in fertility was contributed mainly by the higher socioeconomic class, more affluent, and educated Singaporeans. Thus, in 1981, the government introduced certain pronatalist policies and incentives to encourage better educated women to produce more children, e.g., tax relief and the elimination of monetary incentives to sterilization acceptors above a

  12. Cohort Fertility Patterns in the Nordic Countries

    DEFF Research Database (Denmark)

    Andersson, Gunnar; Rønsen, Marit; Knudsen, Lisbeth B.

    Previous analyses of period fertility suggest that the trends of the Nordic countries are sufficiently similar to speak of a common "Nordic fertility regime". We investigate whether this assumption can be corroborated by comparing cohort fertility patterns in the Nordic countries. We study...... cumulated and completed fertility of Nordic birth cohorts based on the childbearing histories of women born in 1935 and later derived from the population registers of Denmark, Finland, Norway and Sweden. We further explore childbearing behaviour by women’s educational attainment. The results show remarkable...... similarities in postponement and recuperation between the countries and very small differences in completed fertility across educational groups. Median childbearing age is about 2-3 years higher in the 1960-64-cohort than in the 1950-54-cohort, but the younger cohort recuperates the fertility level...

  13. Differentials of fertility in North and South Gondar zones, northwest Ethiopia: A comparative cross-sectional study

    Directory of Open Access Journals (Sweden)

    Worku Alemayehu

    2008-12-01

    Full Text Available Abstract Background Ethiopia is one of the most densely populated countries in Africa with an estimated population of 77.1 million in mid-2007. Uncontrolled fertility has adversely influenced the socio-economic, demographic and environmental situations of the country. It is one of the largest and poorest countries that, even in the midst of crisis, has maintained high levels of fertility. This study was aimed at investigating the most important factors influencing fertility behavior in Northwest Ethiopia. Methods A comparative cross-sectional study which included 2424 women aged 25 years and above was undertaken in the Amhara region of Northwest Ethiopia. The study subjects were grouped into high fertile and low fertile categories. There were 1011 and 1413 women in the high and low fertile groups, respectively. A multi-stage cluster sampling stratified by place of residence was employed to select the required study subjects. Both bivariate and multivariate logistic regression techniques were used to analyze the data. Results Among the 25 variables considered in this study, only 9 of them were found significantly and independently associated with the level of fertility. Women with at least secondary education were at a lower risk of high fertility with OR = 0.37 (95% CI: 0.21 to 0.64 compared to those with no formal education. However, women with primary education did not show any significant difference when compared with the same baseline group. Age at first marriage was inversely associated with the number of children ever born alive. Place of residence, household expenditure, number of children who have died, attitude towards using contraceptives, women's knowledge on the safe period, and current marital status were the other variables that showed significant associations with the level of fertility. Conclusion Female education beyond the primary level, reduced infant and child mortality, delayed marriage and correct knowledge on the safe

  14. The population threat.

    Science.gov (United States)

    Teitelbaum, M S

    1992-01-01

    Commentary is provided on the challenges faced by the new Clinton administration in formulating US key foreign policy initiatives. There is an urgent need to provide balanced and effective foreign aid for reducing high fertility rates in the developing world. There is also a need to effectively monitor the large migrations of populations. Over the past 10 years, the US has not been actively practicing world leadership on population issues. 3 changes in 1993 give impetus to redirect foreign policy: 1) the waning influence of fringe groups who controlled population issues; 2) the campaign promises to restore UN population stabilization programs; and 3) the evidence from the Persian Gulf and Yugoslavia that demographic issues require planning and assessment. Global population growth has been concentrated in the past 40 years, in part due to mortality declines and sustained high fertility. Of significance is the rapidness and momentum of growth. A high percentage are and will be children. Urban population is also growing rapidly in high fertility countries. Countries with high fertility and significant rural-to-urban migration also have large international migrations. The evolution of policy since the 1950s, which for the most part ignored population issues, is discussed. The American debates have been charged with emotionalism: about human sexuality, legitimacy of voluntary fertility control, the role and status of women and men, abortion, intergenerational transfer of obligations, ethnic solidarity and the sovereignty of national borders, and the proper roles of the state versus the marketplace. There have been over 200 years of ideological argument over population issues. The Malthusian argument was that large population size did not increase prosperity, and growth should be limited. The Marxist-Leninist position was that contraception was Malthusian, abortion was a woman's right, and population growth was neutral. By late 1970 the Chinese Maoists adopted the moral

  15. Increasing STEM Competence in Urban, High Poverty Elementary School Populations

    Directory of Open Access Journals (Sweden)

    Sueanne McKinney

    2017-10-01

    Full Text Available Enhancing STEM competence (e.g., interests, knowledge, skills, and dispositions among urban, high poverty, elementary school populations in the United States (U.S. is and remains a growing national concern, especially since Science, Technology, Engineering and Mathematics (STEM competence is and will continue to be a necessary requisite for gainful employment in the future, according to workforce development experts. In an attempt to address this gap, many urban elementary schools have begun to offer STEM-related programs to increase STEM learning at an early age. STEM competence (interest, knowledge, skills, and dispositions, however, remains low. This paper results in a matrix used to analyze children's fictional literary selections and a model that argues that elementary teachers, as the first point of contact with young students, can affect STEM competence. By adopting a more culturally responsive pedagogy that attends to the 21st Century Learning Skills and the Next Generation Science Standards, teachers can choose literature that serves to excite and reinforce STEM learning.

  16. Antiplatelet therapy in populations at high risk of atherothrombosis.

    Science.gov (United States)

    Faxon, David P; Nesto, Richard W

    2006-05-01

    -risk patient populations. In addition, the REACH registry, a worldwide survey of symptomatic and high-risk patients, has been set up to provide vital epidemiological information regarding the risks of atherothrombosis in order to contribute to the development of better preventive strategies and management regimens for at-risk patients.

  17. Changes of the content of oil products in the oil-polluted peat soil of a high-moor bog in a field experiment with application of lime and fertilizers

    Science.gov (United States)

    Erkenova, M. I.; Tolpeshta, I. I.; Trofimov, S. Ya.; Aptikaev, R. S.; Lazarev, A. S.

    2016-11-01

    A field model experiment on stimulating the activity of native oil microorganisms-decomposers was performed on an oil-polluted area in a high-moor bog under its total flooding in the northern taiga (Western Siberia). For two summer months, the doses of lime and nitrogen, phosphorus, and potassium fertilizers applied have caused a decrease in the oil products (OP) content by 54% relative to their initial amount. The decrease of the OP content in the soil profiles was nonuniform, and at the depth of 30-50 cm it was accompanied by the acidification of peat. The stimulation of the activity of aboriginal microorganisms by applying lime and mineral fertilizers led to the development of migration processes with the participation of oil and products of its transformation. These processes differed from those in the soil without application of lime and fertilizers. An original technology of applying lime and fertilizers providing minimal disturbances the upper 50-cm peat layer is suggested.

  18. High school students' understanding and problem solving in population genetics

    Science.gov (United States)

    Soderberg, Patti D.

    This study is an investigation of student understanding of population genetics and how students developed, used and revised conceptual models to solve problems. The students in this study participated in three rounds of problem solving. The first round involved the use of a population genetics model to predict the number of carriers in a population. The second round required them to revise their model of simple dominance population genetics to make inferences about populations containing three phenotype variations. The third round of problem solving required the students to revise their model of population genetics to explain anomalous data where the proportions of males and females with a trait varied significantly. As the students solved problems, they were involved in basic scientific processes as they observed population phenomena, constructed explanatory models to explain the data they observed, and attempted to persuade their peers as to the adequacy of their models. In this study, the students produced new knowledge about the genetics of a trait in a population through the revision and use of explanatory population genetics models using reasoning that was similar to what scientists do. The students learned, used and revised a model of Hardy-Weinberg equilibrium to generate and test hypotheses about the genetics of phenotypes given only population data. Students were also interviewed prior to and following instruction. This study suggests that a commonly held intuitive belief about the predominance of a dominant variation in populations is resistant to change, despite instruction and interferes with a student's ability to understand Hardy-Weinberg equilibrium and microevolution.

  19. Investigation of spectral interferences in the determination of lead in fertilizers and limestone samples using high-resolution continuum source graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Aline R. [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Becker, Emilene M.; François, Luciane L.; Jesus, Alexandre de [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Vale, Maria Goreti R. [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Welz, Bernhard [Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil); Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Dessuy, Morgana B., E-mail: mbdessuy@ufrgs.br [Instituto de Química, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, RS (Brazil); Andrade, Jailson B. de [Instituto Nacional de Ciência e Tecnologia do CNPq — INCT de Energia e Ambiente, Universidade Federal da Bahia, Salvador, BA (Brazil)

    2014-11-01

    In the present work, spectral interferences on the determination of lead in fertilizer and limestone samples were investigated using high-resolution continuum source graphite furnace atomic absorption spectrometry at the main analytical lines: 217.001 and 283.306 nm. For these investigations, samples were introduced into the furnace as slurry together with a mixture of Pd and Mg as chemical modifier. Spectral interferences were observed for some samples at both analytical lines. In order to verify whether a wet digestion procedure would avoid these interferences, a reference method for wet digestion of fertilizers was employed as an alternative sample preparation procedure. However, the same interferences were also observed in the digested samples. In order to identify and eliminate the fine-structured background using a least-squares background correction, reference spectra were generated using the combination of different species. The use of the latter technique allowed the elimination of spectral interferences for most of the investigated samples, making possible the determination of lead in fertilizer and limestone samples free of interferences. The best results were found using a reference spectrum of NH{sub 4}H{sub 2}PO{sub 4} at 217.001 nm, and a mixture of H{sub 2}SO{sub 4} + Ca and HNO{sub 3} + Ca at the 283.306 nm line. The accuracy of the method was evaluated using a certified reference material “Trace Elements in Multi-Nutrient Fertilizer”. Similar results were obtained using line source graphite furnace atomic absorption spectrometry with Zeeman-effect background correction, indicating that the latter technique was also capable to correct the spectral interferences, at least in part. - Highlights: • Spectral interferences on the determination of lead in fertilizers and limestone. • The analytical lines at 217.001 nm and 283.306 nm using HR-CS GF AAS. • Various combinations of compounds were used to create reference spectra. • LSBC

  20. HIV and male fertility at the University Teaching Hospital Lusaka ...

    African Journals Online (AJOL)

    Background: There has been anecdotal evidence of a declining male fertility in Zambia over the last 10 years1. This prospective study of men seen in the fertility clinic was designed to look for an association between the increasing HIV infection in the population and male fertility. Methods: This prospective study compared ...

  1. Determinants of fertility in Namibia | Indongo | African Journal of ...

    African Journals Online (AJOL)

    In-depth studies on fertility in Namibia have been lacking so far. This examines the fertility trends in Namibia over the past 2 decades and examines fertility differentials across the various sub-groups of Namibia population, and factors affecting such differentials using NDHS data. Estimates of the amount of variance in the ...

  2. Family type, family resources, and fertility among Iranian peasant women.

    Science.gov (United States)

    Aghajanian, A

    1978-01-01

    A survey of Iranian peasants was undertaken in 1974 to test the assumption that the extended family structure encourages high fertility in all cases. Data were collected on household characteristics, fertility, age of women, age of marriage of women, education of husbands (few women were literate), size of landholding, and number of relatives (other than the husband, wife, and unmarried children) in the household. These data were submitted to multiple classification analysis which allows the effects of variables other than the one under consideration to be controlled. It was found that women in nuclear families bore 6.0 children as compared to 5.3 in extended families when age of women, age of marriage of women, and education of husbands were controlled. When family size was considered in light of the size of the landholding, it was found that for all sizes of landholding, the mean size of extended families was larger than that of nuclear families. Thus, extended families reduce this population pressure by discouraging fertility; for each nonnuclear family member, fertility is reduced by 0.65 children. It is concluded that the extended family is flexible enough to encourage or discourage fertility depending upon the demographic and economic characteristics of the household.

  3. A simple and fast method for assessment of the nitrogen-phosphorus-potassium rating of fertilizers using high-resolution continuum source atomic and molecular absorption spectrometry

    Science.gov (United States)

    Bechlin, Marcos André; Fortunato, Felipe Manfroi; da Silva, Ricardo Moutinho; Ferreira, Edilene Cristina; Gomes Neto, José Anchieta

    2014-11-01

    The determination of N, P, and K in fertilizers by high-resolution continuum source flame atomic and molecular absorption spectrometry is proposed. Under optimized conditions, measurements of the diatomic molecules NO and PO at 215.360 and 247.620 nm, respectively, and K using the wing of the alternative line at 404.722 nm allowed calibration curves to be constructed in the ranges 500-5000 mg L- 1 N (r = 0.9994), 100-2000 mg L- 1 P (r = 0.9946), and 100-2500 mg L- 1 K (r = 0.9995). Commercial fertilizers were analyzed by the proposed method and the concentrations of N, P, and K were found to be in agreement with those obtained by Kjeldahl, spectrophotometric, and flame atomic emission spectrometry methods, respectively, at a 95% confidence level (paired t-test). A phosphate rock certified reference material (CRM) was analyzed and the results for P and K were in agreement with the reference values. Recoveries from spiked CRM were in the ranges 97-105% (NO3--N), 95-103% (NH4+-N), 93-103% (urea-N), 99-108% (P), and 99-102% (K). The relative standard deviations (n = 12) for N, P, and K were 6, 4, and 2%, respectively.

  4. Staphylococcus aureus from the German general population is highly diverse.

    Science.gov (United States)

    Becker, Karsten; Schaumburg, Frieder; Fegeler, Christian; Friedrich, Alexander W; Köck, Robin

    2017-01-01

    This prospective cohort study evaluates colonization dynamics and molecular characteristics of methicillin-susceptible and - resistant Staphylococcus aureus (MSSA/MRSA) in a German general population. Nasal swabs of 1878 non-hospitalized adults were screened for S. aureus. Participants were screened thrice in intervals of 6-8 months. Isolates were characterized by spa and agr typing, mecA and mecC possession, respectively, and PCRs targeting virulence factors. 40.9% of all participants carried S. aureus at least once while 0.7% of the participants carried MRSA (mainly spa t011). MSSA isolates (n=1359) were associated with 331 different spa types; t084 (7.7%), t091 (6.1%) and t012 (71, 5.2%) were predominant. Of 206 participants carrying S. aureus at all three sampling time points, 14.1% carried the same spa type continuously; 5.3% carried different spa types with similar repeat patterns, but 80.6% carried S. aureus with unrelated spa types. MSSA isolates frequently harboured genes encoding enterotoxins (sec: 16.6%, seg: 63.1%, sei: 64.5%) and toxic shock syndrome toxin (tst: 17.5%), but rarely Panton-Valentine leukocidin (lukS-PV/lukF-PV: 0.2%). MSSA colonizing human nares in the community are clonally highly diverse. Among those constantly carrying S. aureus, clonal lineages changed over time. The proportion of persistent S. aureus carriers was lower than reported elsewhere. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. TENORM: Fertilizer and Fertilizer Production Wastes

    Science.gov (United States)

    Phosphate rock is used in the production of phosphate fertilizers. Due to its chemical properties, phosphate rock may contain significant quantities of naturally occurring radioactive materials (NORM).

  6. Global Fertilizer and Manure, Version 1: Phosphorus Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phosphorus Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of phosphorus fertilizer nutrients...

  7. Global Fertilizer and Manure, Version 1: Nitrogen Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nitrogen Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of nitrogen fertilizer nutrients...

  8. Community-level education accelerates the cultural evolution of fertility decline.

    Science.gov (United States)

    Colleran, Heidi; Jasienska, Grazyna; Nenko, Ilona; Galbarczyk, Andrzej; Mace, Ruth

    2014-03-22

    Explaining why fertility declines as populations modernize is a profound theoretical challenge. It remains unclear whether the fundamental drivers are economic or cultural in nature. Cultural evolutionary theory suggests that community-level characteristics, for example average education, can alter how low-fertility preferences are transmitted and adopted. These assumptions have not been empirically tested. Here, we show that community-level education accelerates fertility decline in a way that is neither predicted by individual characteristics, nor by the level of economic modernization in a population. In 22 high-fertility communities in Poland, fertility converged on a smaller family size as average education in the community increased-indeed community-level education had a larger impact on fertility decline than did individual education. This convergence was not driven by educational levels being more homogeneous, but by less educated women having fewer children than expected, and more highly educated social networks, when living among more highly educated neighbours. The average level of education in a community may influence the social partners women interact with, both within and beyond their immediate social environments, altering the reproductive norms they are exposed to. Given a critical mass of highly educated women, less educated neighbours may adopt their reproductive behaviour, accelerating the pace of demographic transition. Individual characteristics alone cannot capture these dynamics and studies relying solely on them may systematically underestimate the importance of cultural transmission in driving fertility declines. Our results are inconsistent with a purely individualistic, rational-actor model of fertility decline and suggest that optimization of reproduction is partly driven by cultural dynamics beyond the individual.

  9. Many Mobile Health Apps Target High-Need, High-Cost Populations, But Gaps Remain.

    Science.gov (United States)

    Singh, Karandeep; Drouin, Kaitlin; Newmark, Lisa P; Lee, JaeHo; Faxvaag, Arild; Rozenblum, Ronen; Pabo, Erika A; Landman, Adam; Klinger, Elissa; Bates, David W

    2016-12-01

    With rising smartphone ownership, mobile health applications (mHealth apps) have the potential to support high-need, high-cost populations in managing their health. While the number of available mHealth apps has grown substantially, no clear strategy has emerged on how providers should evaluate and recommend such apps to patients. Key stakeholders, including medical professional societies, insurers, and policy makers, have largely avoided formally recommending apps, which forces patients to obtain recommendations from other sources. To help stakeholders overcome barriers to reviewing and recommending apps, we evaluated 137 patient-facing mHealth apps-those intended for use by patients to manage their health-that were highly rated by consumers and recommended by experts and that targeted high-need, high-cost populations. We found that there is a wide variety of apps in the marketplace but that few apps address the needs of the patients who could benefit the most. We also found that consumers' ratings were poor indications of apps' clinical utility or usability and that most apps did not respond appropriately when a user entered potentially dangerous health information. Going forward, data privacy and security will continue to be major concerns in the dissemination of mHealth apps. Project HOPE—The People-to-People Health Foundation, Inc.

  10. Factors affecting the development of in vitro fertilization in camelids

    Directory of Open Access Journals (Sweden)

    Trasorras VL

    2016-12-01

    Full Text Available In any program of in vitro embryo production, the ultimate goal is to develop high quality embryos being able to get a normal pregnancy and finally resulting in the birth of a healthy offspring, goal not reach yet in camelids. The application of assisted reproductive techniques, such as in vitro fertilization and subsequent in vitro embryo culture, can extend the knowledge of early embryonic development and make possible the increase of the population of genetically superior animals.

  11. Is Wildlife Fertility Control Always Humane?

    Directory of Open Access Journals (Sweden)

    Jordan O. Hampton

    2015-10-01

    Full Text Available Investigation of fertility control techniques to reduce reproductive rates in wildlife populations has been the source of much research. Techniques targeting wildlife fertility have been diverse. Most research into fertility control methods has focused upon efficacy, with few studies rigorously assessing animal welfare beyond opportunistic anecdote. However, fertility control techniques represent several very different mechanisms of action (modalities, each with their own different animal welfare risks. We provide a review of the mechanisms of action for fertility control methods, and consider the role of manipulation of reproductive hormones (“endocrine suppression” for the long-term ability of animals to behave normally. We consider the potential welfare costs of animal manipulation techniques that are required to administer fertility treatments, including capture, restraint, surgery and drug delivery, and the requirement for repeated administration within the lifetime of an animal. We challenge the assumption that fertility control modalities generate similar and desirable animal welfare outcomes, and we argue that knowledge of reproductive physiology and behaviour should be more adeptly applied to wild animal management decisions. We encourage wildlife managers to carefully assess long-term behavioural risks, associated animal handling techniques, and the importance of positive welfare states when selecting fertility control methods as a means of population control.

  12. Occupation and fertility on the frontier: Evidence from the state of Utah

    Directory of Open Access Journals (Sweden)

    Thomas N. Maloney

    2014-03-01

    Full Text Available Background: Most of what we know about fertility decline in the United States comes from aggregate (often state or county level data sources. It is difficult to identify variation in fertility change across socio-economic classes in such data, although understanding such variation would provide deeper insight into the history of the fertility transition. Objective: We use rich micro-level data to examine differences across occupational classes in fertility levels and in the timing and pace of change in fertility in the US state of Utah in the late 19th and early 20th centuries. Methods: Our evidence comes from the Utah Population Database, which contains several generations of linked family histories, including information on residents of Utah from the mid-1800s to the present. We use standard linear regression models to identify variation in fertility across birth cohorts and occupational classes as well as cohort-occupation interaction effects (to identify differences across classes in the pace of change over time Results: Families of white collar workers led changes in many fertility-related behaviors, particularly those tied to the start of family life (marriage age and first birth interval. Farm families had high fertility levels and added children into late ages, although they also experienced declining fertility. Conclusions: Examination of detailed micro-level data on fertility change identifies important differences in the patterns of change which may be tied to variation in relevant economic circumstances - for instance, the length of education and training required for particular occupations, or the need for family-based labor on the farm.

  13. Slovakia: Fertility between tradition and modernity

    OpenAIRE

    Michaela Potančoková; Boris Vano; Viera Pilinská; Danuša Jurčová

    2008-01-01

    In the last 60 years, Slovakia has experienced comparatively high and most recently very low fertility, long periods of stable fertility alternating with periods of changes, periods of substantial as well as lesser state interventions. Fertility was above replacement in 1990 and declined to the lowest-low levels during the period of transformation. Postponement of life course transitions - leaving the parental home, marrying and becoming a parent - became widespread among younger cohorts afte...

  14. Efficacy of Kisspeptin-54 to Trigger Oocyte Maturation in Women at High Risk of Ovarian Hyperstimulation Syndrome (OHSS) During In Vitro Fertilization (IVF) Therapy.

    Science.gov (United States)

    Abbara, Ali; Jayasena, Channa N; Christopoulos, Georgios; Narayanaswamy, Shakunthala; Izzi-Engbeaya, Chioma; Nijher, Gurjinder M K; Comninos, Alexander N; Peters, Deborah; Buckley, Adam; Ratnasabapathy, Risheka; Prague, Julia K; Salim, Rehan; Lavery, Stuart A; Bloom, Stephen R; Szigeti, Matyas; Ashby, Deborah A; Trew, Geoffrey H; Dhillo, Waljit S

    2015-09-01

    In vitro fertilization (IVF) treatment is an effective therapy for infertility, but can result in the potentially life-threatening complication, ovarian hyperstimulation syndrome (OHSS). This study aimed to investigate whether kisspeptin-54 can be used to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS. This was a phase 2, multi-dose, open-label, randomized clinical trial of 60 women at high risk of developing OHSS carried out during 2013-2014 at Hammersmith Hospital IVF unit, London, United Kingdom. Following a standard recombinant FSH/GnRH antagonist protocol, patients were randomly assigned to receive a single injection of kisspeptin-54 to trigger oocyte maturation using an adaptive design for dose allocation (3.2 nmol/kg, n = 5; 6.4 nmol/kg, n = 20; 9.6 nmol/kg, n = 15; 12.8 nmol/kg, n = 20). Oocytes were retrieved 36 h after kisspeptin-54 administration, assessed for maturation, and fertilized by intracytoplasmic sperm injection with subsequent transfer of one or two embryos. Women were routinely screened for the development of OHSS. Oocyte maturation was measured by oocyte yield (percentage of mature oocytes retrieved from follicles ≥ 14 mm on ultrasound). Secondary outcomes include rates of OHSS and pregnancy. Oocyte maturation occurred in 95% of women. Highest oocyte yield (121%) was observed following 12.8 nmol/kg kisspeptin-54, which was +69% (confidence interval, -16-153%) greater than following 3.2 nmol/kg. At all doses of kisspeptin-54, biochemical pregnancy, clinical pregnancy, and live birth rates per transfer (n = 51) were 63, 53, and 45%, respectively. Highest pregnancy rates were observed following 9.6 nmol/kg kisspeptin-54 (85, 77, and 62%, respectively). No woman developed moderate, severe, or critical OHSS. Kisspeptin-54 is a promising approach to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS.

  15. The fertility transition in Cuba and the Federal Republic of Korea: the impact of organised family planning.

    Science.gov (United States)

    Noble, J; Potts, M

    1996-04-01

    South Korea and Cuba are dissimilar in religion, economy, culture and attitudes toward premarital sexual relations. In 1960, Korea instituted a national family planning programme to combat rapid population growth. Cuba explicitly rejected Malthusian policies, but made family planning universally available in 1974 in response to health needs. Both countries have undergone rapid fertility declines and today have less than replacement level fertility. Both countries have also used a similar mixture of methods, including a high prevalence of female sterilisation. Abortion has played a major role in the fertility decline of both countries, rising in the first half of the fertility transition and then falling, although remaining a significant variable in the second half. It is concluded that access to contraception, voluntary sterilisation, and safe abortion has a direct impact on fertility and has been associated with a rapid fall in family size in two very different countries.

  16. HLA and fertility

    Energy Technology Data Exchange (ETDEWEB)

    Ober, C. [Univ. of Chicago, IL (United States)

    1995-11-01

    The recent paper by Jin et al., reporting that class 11 region major histocompatibility complex genes may influence embryonic loss in outbred couples supports previous results of our studies of HLA and fertility in the Hutterites. However, the authors have incorrectly cited our work and have omitted the reference that is most relevant to their results. The paper by Kostyu et al. is incorrectly referred to in the introduction as providing evidence for HLA sharing being associated with recurrent spontaneous abortion. The Kostyu et al. paper does not include any data on fertility or reproduction but reports frequencies of individuals who are homozygous at the HLA-A, -C, -B, -DR, and -DQ loci in the Hutterite population. In fact, recurrent spontaneous abortion has not been observed in any of the couples in our sample of >500 Hutterite couples. References more appropriate to the association between HLA sharing and recurrent miscarriage are those by Komlos et al., Schacter et al., Gerencer and Kastelan, and Beer et al. It might also be worth pointing out that many studies of recurrent miscarriage in outbred couples have not found an association with HLA sharing; examples include the studies of Ergolu et al., Oksenberg et al., and Christiansen et al., among others. 11 refs.

  17. Fertility, kinship and the evolution of mass ideologies.

    Science.gov (United States)

    David-Barrett, Tamas; Dunbar, Robin I M

    2017-03-21

    Traditional human societies are organised around kinship, and use kinship networks to generate large scale community projects. This is made possible by a combination of linguistic kin recognition, a uniquely human trait, which is mediated by the reliability of kin as collaborators. When effective fertility falls, this results in two simultaneous effects on social networks: there are fewer kin that can be relied on, and the limiting effect of the local kin-clustering becomes stronger. To capture this phenomenon, we used a model of kinship lineages to build populations with a range of fertility levels combined with a behavioural synchrony model to measure the efficiency of collective action generated on kin networks within populations. Our findings suggest that, whenever effective cooperation depends on kinship, falling fertility creates a crisis when it results in too few kin to join the community project. We conclude that, when societies transition to small effective kin networks, due to falling fertility, increased relative distance to kin due to urbanisation or high mortality due to war or epidemics, they will be able to remain socially cohesive only if they replace disappearing kin networks with quasi-kin alternatives based on membership of guilds or clubs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Fertilization success in Galeolaria caespitosa (Polychaeta: Serpillidae: gamete characteristics, role of sperm dilution, gamete age, and contact time

    Directory of Open Access Journals (Sweden)

    Elena K. Kupriyanova

    2006-12-01

    Full Text Available Variability in gamete traits and the factors affecting fertilization success were studied in a common gregarious broadcast-spawning serpulid polychaete Galeolaria caespitosa. Variability of egg size and sperm velocity were not related to the adult size. High sperm concentrations (107-108 sperm. ml-1 were required to achieve fertilization rates of 60-80%. The gamete contact time required to achieve high fertilization rates (70-80% in G. caespitosa did not exceed 5 minutes of gamete exposure given sufficiently high sperm concentrations. This suggests that attachment of sperm to the egg takes place very rapidly, and a short-term exposure to highly concentrated sperm is a common feature of fertilization ecology of this gregarious species. A sharp decline in fertilization rates at high sperm concentrations usually attributable to polyspermy was not observed. Sperm were motile for up to 6 hours after activation; however, swimming velocity and fertilization success decreased after 2 hours. Eggs of G. caespitosa were fertilizable up to 10 hours after spawning, but the number of embryos resulting from fertilizations by fresh sperm decreased after 2 hours. The gamete traits of G. caespitosa appear to have evolved to enable this sessile organism to reproduce under conditions of high population density and increased risk of polyspermy.

  19. Cancer and fertility : strategies to preserve fertility

    NARCIS (Netherlands)

    Diedrich, K.; Fauser, B. C. J. M.; Devroey, P.

    Fertility preservation is a key component of cancer management in young people. The Fourth Evian Annual Reproduction Workshop Meeting was held in April 2009 to discuss cancer and fertility in young adults. Specialists in oncology, assisted reproduction, embryology and clinical genetics presented

  20. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    Science.gov (United States)

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; Veblen, Thomas T; Smith, Jeremy M.; Kueppers, Lara M.

    2017-01-01

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively.Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers.Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forest and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine.Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.

  1. Mycorrhizas and tropical soil fertility

    NARCIS (Netherlands)

    Cardoso, I.M.; Kuyper, T.W.

    2006-01-01

    Major factors that constrain tropical soil fertility and sustainable agriculture are low nutrient capital, moisture stress, erosion, high P fixation, high acidity with aluminium toxicity, and low soil biodiversity. The fragility of many tropical soils limits food production in annual cropping

  2. Warm and Fertile Sub-Humid Conditions Enhance Litterfall to Sustain High Soil Respiration Fluxes in a Mediterranean Cork Oak Forest

    National Research Council Canada - National Science Library

    Lobna Zribi; Florent Mouillot; Fatma Gharbi; Jean-Marc Ourcival; Belgacem Hanchi

    2015-01-01

    .... This study investigates seasonal soil respiration rates and underlying mechanisms under wetter, warmer, and more fertile conditions in a Mediterranean cork oak forest of Northern Tunisia (Africa...

  3. Will human populations be limited by food?

    Science.gov (United States)

    Warren, S. G.

    2016-12-01

    Historical examples of demographic change, in China, Italy, Nigeria, Utah, the Philippines, and elsewhere, together with simple mathematics and biological principles, show that stabilizing world population before it is limited by food supply will be more difficult than is generally appreciated. United Nations population projections are based on a logical fallacy in that they assume, in spite of the absence of necessary negative feedbacks, that all nations will converge rapidly to replacement-level fertility and thereafter remain at that level. The benign projections that have resulted from this assumption may have hindered efforts to make availability of birth-control a priority in development-aid. Education of women and provision of contraceptives have caused dramatic reductions in fertility, but many groups, including some that are well-educated, maintain high fertility. Small groups with persistent high fertility can grow to supplant low-fertility groups, resulting in continued growth of the total population. The global average fertility rate could rise even if each country's fertility rate is falling. In some low-fertility European countries where deaths exceed births, the population continues to grow because of immigration. Producing more than two offspring is normal for all animal species with stable populations, because their populations are limited by resources or predation rather than birth control. It may therefore be appropriate to view the growth of human population as the result not of excess fertility but rather of excess food. Even if the fertility rate is maintained far in excess of 2, the population cannot grow if food is limiting. Without the agricultural advances of the 20thcentury, world population could not have grown as it did from 1.7 billion in 1900 to 6 billion in 2000. The food supply may be enhanced in the future by genetic engineering and other innovations, but it may be limited by water shortage, climate change, pollution, and energy

  4. The Population Problem as Economic Disarticulation.

    Science.gov (United States)

    Yapa, Lakshman S.

    1985-01-01

    Overpopulation exists when people lack the basic means of subsistence, or when there is massive and permanent unemployment. Population problems of developing countries are examined, and causes of high rates of fertility are discussed. The utilization of productive resources in solving population problems is also examined. (RM)

  5. Fertility assurance through extrapair fertilizations and male paternity defense.

    Science.gov (United States)

    Fishman, Michael A; Stone, Lewi; Lotem, Arnon

    2003-03-07

    Extrapair paternity has been observed in many formally monogamous species. Male pursuit of extrapair fertilizations is explained by the advantages of having offspring that receive essential paternal care from other males. Since females are capable of exercising a degree of control over the post-copulatory sperm competition, extrapair paternity cannot persist unless it confers fitness benefits on cuckolding females. Thus, extrapair paternity involves cooperation between mated females and extrapair males. On the other hand, paired males frequently exhibit strategies that minimize their loss of paternity and/or conserve paternal investment if paternity is lost. Hence, extrapair attributes of diverse species and populations reported in the literature are particular solutions of evolutionary games involving gender-specific cuckolding/anti-cuckolding strategies. Here we use methods of evolutionary game theory to study the role of male paternity guarding strategies in situations where females seek extrapair fertilizations for reasons of genetic compatibility and/or in pursuit of genetic diversity for their offspring. Our results indicate that in these circumstances pursuit of extrapair fertilizations is the only evolutionary stable female strategy. Males, on the other hand, have two, mutually exclusive, evolutionary stable strategies: full time pursuit of extrapair fertilizations and a compromise strategy wherein they protect in-pair paternity during their mate's fertile periods and pursue extrapair paternity the rest of the time. The relative merits of these two strategies are determined by the efficiency of male in-pair paternity defense, breeding synchrony, fitness advantages of extrapair over in-pair offspring, and the intensity of competition for extrapair fertilizations from floater males.

  6. Plant fertilizer poisoning

    Science.gov (United States)

    Plant fertilizers and household plant foods are used to improve plant growth. Poisoning can occur if someone swallows these products. Plant fertilizers are mildly poisonous if small amounts are swallowed. ...

  7. Male Fertility Issues

    Science.gov (United States)

    Fertility issues are common in boys and men getting cancer treatment. Fertility preservation options include sperm banking, testicular shielding, testicular sperm extraction (TESE), and testicular tissue freezing. Support and clinical trials are listed.

  8. Fertility Treatments for Females

    Science.gov (United States)

    ... for Females Share Facebook Twitter Pinterest Email Print Fertility Treatments for Females Once a woman is diagnosed ... The presence or absence of male factor infertility Fertility treatments are most likely to benefit women whose ...

  9. Infertility and Fertility

    Science.gov (United States)

    ... Facebook Twitter Pinterest Email Print About Infertility and Fertility "Infertility" is a term that describes when a ... infertility and recurrent pregnancy loss: A committee opinion. Fertility and Sterility, 99 (1), 63. [top] American Society ...

  10. TCRC Fertility Page

    Science.gov (United States)

    The Testicular Cancer Resource Center The TCRC Fertility Page Testicular Cancer and fertility are interrelated in numerous ways. TC usually affects young men still in the process of having a family. ...

  11. Protect Your Fertility

    Science.gov (United States)

    ... brochure briefly explains how such behaviors put your fertility at risk. Decisions and choices that you make ... your teens and early twenties can affect your fertility for years to come. This prevention guide was ...

  12. How farmers in Switzerland perceive fertilizers from recycled anthropogenic nutrients (urine).

    Science.gov (United States)

    Lienert, J; Haller, M; Berner, A; Stauffacher, M; Larsen, T A

    2003-01-01

    We studied acceptance of a urine-based fertilizer product using a mail survey of 467 Swiss farmers. We distinguished among four production types: organic or IP farming, and with or without vegetable production. Considering that the idea of urine-based fertilizers is new, acceptance among the answering farmers was surprisingly high, with 57% explicitly stating that they thought it was a good or very good idea, and 42% willing to purchase such a product. The farmers of different production types did not differ strongly in their attitude towards urine-based fertilizers. Especially IP and vegetable farmers, who purchased additional fertilizers anyway, seem willing to accept urine-based fertilizers, hereby preferring a grainy, odorless ammonium nitrate fertilizer. Absolutely essential is a hazard-free product: 30% of all farmers had concerns regarding micropollutants. Based on fertilizer data, we demonstrate an existing demand for the nutrients N, P, and K in Switzerland, which could be partially substituted by a recycled urine product. Finally, we discuss methodological requirements of social science surveys. To obtain representative data on an entire population in a mail survey, multiple contacts with respondents are necessary. We argue that information and participation of stakeholders at an early stage is essential for successful technology transfer.

  13. Adolescent fertility in Cuba: some reflections on its behavior by provinces and areas of residence

    Directory of Open Access Journals (Sweden)

    Daylin Rodríguez Javiqué

    2016-07-01

    Full Text Available This paper aims to describe the adolescent fertility in Cuba during the period 2010-2014 and analyze its proximate determinants both nationally and by territory. Based on the data published in Demographic Yearbook, Studies and Data of the Population and birth databases of the National Bureau of Statistics and Information (ONEI, adolescent fertility rates in Cuba are calculated according to the groups 10-14 and 15-19, by province and area of residence. In addition, data on family formation, contraception and abortion of Cuban adolescents are shown. These elements could allow hypothesizing about the behavior of adolescent fertility in Cuba. The first important result is that fertility among 15-19 years group had a slight decrease in the period; however, the 10-14 years group has increased its level. On the other hand, the analysis by area of residence shows that urban fertility has gained prominence in the Cuban provinces, with an increase between 2010 and 2012 in more than half of them. Similarly, about a third of the provinces analyzed show higher levels of adolescent fertility in urban areas than in rural areas. High rates of abortion in adolescence, which exceeds fertility rates in ten provinces of the country; early onset of sexual intercourse and first marriage, and improper use of contraceptive methods, are elements worth looking into in order to find explanations to the reproductive behavior of Cuban adolescents.

  14. Desired Fertility and Number of Children Born Across Time and Space.

    Science.gov (United States)

    Günther, Isabel; Harttgen, Kenneth

    2016-02-01

    Economists have often argued that high fertility rates are mainly driven by women's demand for children (and not by family planning efforts) with low levels of unwanted fertility across countries (and hence with little room for family planning efforts to reduce population growth). We study the relationship between wanted fertility and number of children born in a panel of 200 country-years controlling for country fixed effects and global time trends. In general, we find a close relationship between wanted and actual fertility, with one desired child leading to one additional birth. However, our results also indicate that in the last 20 years, the level of unwanted births has stayed at 2 across African countries but has, on average, decreased from 1 to close to 0 in other developing countries. Hence, women in African countries are less able to translate child preferences into birth outcomes than women in other developing countries, and forces other than fertility demand have been important for previous fertility declines in many developing countries. Family planning efforts only partially explain the observed temporal and spatial differences in achieving desired fertility levels.

  15. Staphylococcus aureus from the German general population is highly diverse

    NARCIS (Netherlands)

    Becker, Karsten; Schaumburg, Frieder; Fegeler, Christian; Friedrich, Alexander W.; Kock, Robin

    Objectives: This prospective cohort study evaluates colonization dynamics and molecular characteristics of methicillin-susceptible and - resistant Staphylococcus aureus (MSSA/MRSA) in a German general population. Methods: Nasal swabs of 1878 non-hospitalized adults were screened for S. aureus.

  16. Greece's high dentist to population ratio: comparisons, causes, and effects.

    Science.gov (United States)

    Koletsi-Kounari, Haroula; Papaioannou, William; Stefaniotis, Theodoros

    2011-11-01

    Reaching the optimal dentist to population ratio is a common health policy challenge around the world, but while many countries have too few dentists for their populations, Greece is facing the opposite problem. This study was designed to describe and analyze trends in the number and distribution of dentists in Greece over the last thirty years and compare the Greek dentist to population ratio with that of the other twenty-six European Union (EU) countries. Demographic data for Greece were obtained from the Hellenic Dental Association and the National Statistical Service of Greece and were analyzed using nonparametric statistical tests. Data for the other EU countries were derived from various authoritative sources. In Greece, the number of dentists per 10,000 inhabitants increased significantly (pdentists during the decade 1979-88 (30.4 percent) was significant (pdentists practiced in the Attica Prefecture (Athens) (55.2 percent and 52.6 percent, respectively), but this situation changed significantly in 2007 (pdentists remained almost the same from 1982 until 2007, but female dentists' location of practice changed significantly (pdentist to population ratio, Greece has significant oral health access problems.

  17. FEMALE FERTILITY

    African Journals Online (AJOL)

    hi ghly significantly (P500001) différent in seed set rates but between-clone effects were higher than Within-clone effects. Number of seeds was signii'icantly negatively correlated with style length, ovary length and diameter of the style base. Path analysis indicated a high residual, ... The edible bananas have 22, 33, or 44.

  18. Effects of plant population and nitrogen fertilizer on yield and efficiency of maize-bean intercropping Efeito de população de plantas e adubação nitrogenada na produção e eficiência do consórcio milho-feijão

    Directory of Open Access Journals (Sweden)

    Luiz Balbino Morgado

    2003-11-01

    Full Text Available Nitrogen supply and plant population are basic parameters for cereal-legume intercropping. In order to study plant population and nitrogen fertilizer effects on yield and yield efficiency of maize-bean intercropping, a field experiment was established. Three bean plant populations and three nitrogen levels were used. Maize dry matter accumulation decreased with increases in bean plant population. Competitive effect of intercrop beans on maize yields was high at higher plant populations, being decreased by nitrogen fertilizer; application of 50 kg ha-1 N was very efficient in increasing maize cob yield. Intercropping significantly decreased harvest index of beans in all plant population and nitrogen fertilizer situations. The efficiency of intercropping, compared to sole cropping, was evidenced by the values obtained for Land Equivalent Ratio (LER for biomass, cob and pod yields that increased with increases in bean plant populations and nitrogen fertilizer levels.A disponibilidade de nitrogênio e a população de plantas são parâmetros básicos para o consórcio de gramíneas e leguminosas. Os efeitos de diferentes populações de plantas de feijão e níveis de nitrogênio na produção e eficiência do consórcio milho-feijão foram estudados em um experimento de campo. Foram usadas três populações de plantas de feijão e três níveis de nitrogênio. O acúmulo de matéria seca do milho durante o ciclo vegetativo decresceu à proporção que a população de feijão aumentou. O efeito competitivo do feijão na produção do milho consorciado, que se mostrou maior nas maiores populações de plantas, foi atenuado pela aplicação da adubação nitrogenada; a aplicação de 50 kg ha-1 de N foi muito eficiente no aumento da produção de espiga do milho. O consórcio diminuiu significativamente o índice de colheita do feijão em todas as populações de plantas e em todos os níveis de nitrogênio aplicados. A eficiência do cons

  19. Slow fertilization of stickleback eggs: the result of sexual conflict?

    Directory of Open Access Journals (Sweden)

    Frommen Joachim G

    2006-05-01

    Full Text Available Abstract Background The fertilization success in sperm competition in externally fertilizing fish depends on number and quality of sperm. The time delay between sequential ejaculations may further influence the outcome of sperm competition. Such a time interval can load the raffle over fertilization if fertilization takes place very fast. Short fertilization times are generally assumed for externally fertilizing fish such as the three-spined stickleback (Gasterosteus aculeatus. In this pair-spawning fish, territorial males often try to steal fertilizations in nests of neighbouring males. This sneaking behaviour causes sperm competition. Sneakers will only get a share of paternity when eggs are not fertilized immediately after sperm release. Contrary to males, females may be interested in multiple paternity of their clutch of eggs. There thus may be a sexual conflict over the speed of fertilization. Results In this study we used two different in vitro fertilization experiments to assess how fast eggs are fertilized in sticklebacks. We show that complete fertilization takes more than 5 min which is atypically long for externally fertilizing fishes. Conclusion This result suggests that the time difference does not imply high costs to the second stickleback male to ejaculate. Slow fertilization (and concomitant prolonged longevity of sperm may be the result of sexual conflict in which females aimed at complete fertilization and/or multiple paternity.

  20. Cohort Fertility Patterns in the Nordic Countries

    DEFF Research Database (Denmark)

    Andersson, Gunnar; Rønsen, Marit; Knudsen, Lisbeth B.

    2009-01-01

    Previous analyses of period fertility suggest that the trends of the Nordic countries are sufficiently similar to speak of a common "Nordic fertility regime". We investigate whether this assumption can be corroborated by comparing cohort fertility patterns in the Nordic countries. We study...... cumulated and completed fertility of Nordic birth cohorts based on the childbearing histories of women born in 1935 and later derived from the population registers of Denmark, Finland, Norway, and Sweden. We further explore childbearing behaviour by women's educational attainment. The results show...... remarkable similarities in postponement and recuperation between the countries. Median childbearing age is about 2-3 years higher in the 1960-64 cohort than in the 1950-54 cohort, but the younger cohort recuperates the fertility level of the older cohort at ages 30 and above. A similar pattern...

  1. Environmentally friendly slow-release nitrogen fertilizer.

    Science.gov (United States)

    Ni, Boli; Liu, Mingzhu; Lü, Shaoyu; Xie, Lihua; Wang, Yanfang

    2011-09-28

    To sustain the further world population, more fertilizers are required, which may become an environmental hazard, unless adequate technical and socioeconomic impacts are addressed. In the current study, slow-release formulations of nitrogen fertilizer were developed on the basis of natural attapulgite (APT) clay, ethylcellulose (EC) film, and sodium carboxymethylcellulose/hydroxyethylcellulose (CMC/HEC) hydrogel. The structural and chemical characteristics of the product were examined. The release profiles of urea, ammonium sulfate, and ammonium chloride as nitrogen fertilizer substrates were determined in soil. To further compare the release profiles of nitrogen from different fertilizer substrates, a mathematical model for nutrient release from the coated fertilizer was applied to calculate the diffusion coefficient D. The influence of the product on water-holding and water-retention capacities of soil was determined. The experimental data indicated that the product can effectively reduce nutrient loss, improve use efficiency of water, and prolong irrigation cycles in drought-prone environments.

  2. Fertilizer micro-dosing

    International Development Research Centre (IDRC) Digital Library (Canada)

    millet, sorghum) under micro-dosing and water harvesting. • Farmers' access to fertilizer has been improved by an innovative 'warrantage' credit scheme, that has enabled over 1,000 farmers (30% women), to purchase and use more fertilizer on food crops. Fertilizer micro-dosing: a profitable innovation for. Sahelian women.

  3. Who fertilizes the forest?

    Science.gov (United States)

    Kevin T. Smith

    2016-01-01

    Tree fertilization is a common service provided by commercial arborists and landscapers. Customers and clients are familiar with fertilization from the care of house or garden plants. Any hardware or garden supply store has attractive packages of colored crystals or liquid solutions that promise rapid growth and abundant blossoms. This familiarity with fertilization of...

  4. Patriarchy and fertility in Albania

    Directory of Open Access Journals (Sweden)

    Mathias Lerch

    2013-07-01

    Full Text Available BACKGROUND Theories of fertility collapse in the post-socialist era imply a decline in the moral primacy of traditional social institutions. Yet gender inequality actually increased in many countries, and there is a scarcity of empirical evidence for the role played by traditional social institutions in reproductive decision-making. OBJECTIVE We investigate whether patriarchal institutions sustained the fertility levels in Albania. The geography of marriage and family enlargement is related to the importance of patriarchy in kinship organisation and in the public sphere. To account for this spatial relationship we test the evidence for different pathways in patriarchal influence on reproductive decision-making including social effects, socialisation in patriarchal ideals, and the promotion of male fertility. METHODS We reconstruct reproductive histories from the 2001 Census and use data on attitudes and fertility intentions from the Reproductive and Health Survey 2002. Multilevel logistic regressions on marriage and (the intention of higher order births are used. RESULTS A majority of women endorsed patriarchal ideals and fertility transition was less advanced in more patriarchal municipalities. Patriarchal kinship organisation promoted early marriages and high fertility, which is shown to be achieved by social learning among peers and intergenerational social influences respectively, as well as by women's socialisation and a stopping behaviour in childbearing dominated by son-preference. Although gender inequality in the public sphere has also sustained the level of fertility and decreased the risk of marriage, it was not accounted for by these pathways of patriarchal influence. CONCLUSIONS Despite Albania's gradual opening to the world in a period of economic and political crisis, traditional social institutions remain important for family behaviours.

  5. Microbial community response during the iron fertilization experiment LOHAFEX

    Digital Repository Service at National Institute of Oceanography (India)

    Thiele, S.; Fuchs, B.M.; Ramaiah, N.; Amanna, R.

    Iron fertilization experiments in high nutrient-low chlorophyll areas are known to induce phytoplankton blooms. However, little is known about the response of the microbial community upon iron fertilization. As part of the LOHAFEX experiment...

  6. Fertilizer Emission Scenario Tool for crop management system scenarios

    Science.gov (United States)

    The Fertilizer Emission Scenario Tool for CMAQ is a high-end computer interface that simulates daily fertilizer application information for any gridded domain. It integrates the Weather Research and Forecasting model and CMAQ.

  7. HIGH RESOLUTION GLOBAL GRIDDED DATA FOR USE IN POPULATION STUDIES

    Directory of Open Access Journals (Sweden)

    C. T. Lloyd

    2017-07-01

    Full Text Available Open access geospatial data represent a range of metrics relevant to global human population mapping at fine spatial scales. Detailed and contemporary spatial datasets that accurately describe population distributions are vital in order to measure impacts of population growth, monitor change, and plan interventions. To construct such datasets the harmonisation of geospatial data layers is a prerequisite because layer specifications differ widely. To this end the WorldPop Project is producing an open access archive of 3 and 30 arc-second (~ 100 m and ~ 1 km, respectively resolution gridded data in a predominantly open source environment, using OSGEO4W utilities. Five tiled raster datasets form the basis of the archive: (i Viewfinder Panoramas topography clipped to CIESIN national level administrative coastlines; (ii a matching ISO 3166 country identification grid; (iii country area; (iv pixel area; (v and slope layer. Further layers will include transport networks, landcover, urban extent, nightlights, climate, travel time to major cities, forest stand change, livestock densities, vegetation indices, and waterways. We here describe the base datasets and the production methodology in development. The alpha version of the archive can be downloaded both from the WorldPop Dataverse Repository and the WorldPop Project website. The improved and expanded beta version of the archive is in development for release next year, and will offer significantly improved standardisation of country boundaries, and inland water boundaries (forthcoming, to global census unit data.

  8. High resolution global gridded data for use in population studies

    Science.gov (United States)

    Lloyd, Christopher T.; Sorichetta, Alessandro; Tatem, Andrew J.

    2017-01-01

    Recent years have seen substantial growth in openly available satellite and other geospatial data layers, which represent a range of metrics relevant to global human population mapping at fine spatial scales. The specifications of such data differ widely and therefore the harmonisation of data layers is a prerequisite to constructing detailed and contemporary spatial datasets which accurately describe population distributions. Such datasets are vital to measure impacts of population growth, monitor change, and plan interventions. To this end the WorldPop Project has produced an open access archive of 3 and 30 arc-second resolution gridded data. Four tiled raster datasets form the basis of the archive: (i) Viewfinder Panoramas topography clipped to Global ADMinistrative area (GADM) coastlines; (ii) a matching ISO 3166 country identification grid; (iii) country area; (iv) and slope layer. Further layers include transport networks, landcover, nightlights, precipitation, travel time to major cities, and waterways. Datasets and production methodology are here described. The archive can be downloaded both from the WorldPop Dataverse Repository and the WorldPop Project website.

  9. Factors affecting fertility decisions of married men and women living ...

    African Journals Online (AJOL)

    Background: In a setting with high HIV prevalence and high fertility rates, addressing fertility issues of People Living with HIV/AIDS (PLWHA) is crucial. However, understanding of the factors associated with fertility decisions of PLWHA in Ethiopia is remarkably low. Objective: The study was conducted to assess factors ...

  10. Populism

    OpenAIRE

    Abts, Koenraad; Van Kessel, Stijn

    2015-01-01

    Populism is a concept applied to a wide range of political movements and actors across the globe. There is, at the same time, considerable confusion about the attributes and manifestation of populism, as well as its impact on democracy. This contribution identifies the defining elements of the populist ideology and discusses the varieties in which populism manifests itself, for instance as a component of certain party families. We finally discuss various normative interpretations of populism,...

  11. Agriculture in the Fertile Crescent: Continuity and change under climate change

    Science.gov (United States)

    The Fertile Crescent is a highly biodiverse region where most temperate-zone agricultural species originated and were first domesticated. A favorable environment, a special plant community, and an adaptive population combined to initiate the transition from a hunter-gatherer economy to one based on ...

  12. Impaired Glucose Metabolism in Response to High Fat Diet in Female Mice Conceived by In Vitro Fertilization (IVF) or Ovarian Stimulation Alone

    Science.gov (United States)

    Chen, Miaoxin; Wu, Linda; Wu, Fang; Wittert, Gary A.; Norman, Robert J.; Robker, Rebecca L.; Heilbronn, Leonie K.

    2014-01-01

    Individuals conceived by in vitro fertilization (IVF) may be at increased risk of cardio-metabolic disorders. We recently reported that IVF conceived male mice displayed impaired glucose metabolism at normal and high body weights. In this study, we examined glucose metabolism in mature female C57BL/6J mice that were conceived by natural conception (NC), by ovarian stimulation (OS) or by IVF following chow or high-fat diet (HFD) for 8 weeks. By design, litter size was comparable between groups, but interestingly the birth weight of IVF and OS females was lower than NC females (p≤0.001). Mature IVF female mice displayed increased fasting glucose as compared to NC and OS mice, irrespective of diet. Mature IVF and OS mice were also more susceptible to the metabolic consequences of high fat diet as compared with NC females, with impaired glucose tolerance (p≤0.01), whereas peripheral insulin resistance and increased hepatic expression of gluconeogenic genes Ppargc1α, Pck1 and G6pc was observed in IVF mice only (pIVF program distinct metabolic effects in females, but that high fat diet may be required to unmask these effects. This study adds to the growing body of literature that assisted reproduction procedures may increase the risk of developing type 2 diabetes in an obesity prone environment. PMID:25405530

  13. Assortative fertilization in Drosophila.

    Science.gov (United States)

    Markow, T A

    1997-07-22

    The concept of gametic isolation has its origins in the 1937 edition of T. Dobzhansky's Genetics and the Origin of Species. Involving either positive assortative fertilization (as opposed to self-incompatibility) or negative assortative fertilization, it occurs after mating but prior to fertilization. Gametic isolation is generally subsumed under either prezygotic or postmating isolation and thus has not been the subject of extensive investigation. Examples of assortative fertilization in Drosophila are reviewed and compared with those of other organisms. Potential mechanisms leading to assortative fertilization are discussed, as are their evolutionary implications.

  14. Why do patients discontinue fertility treatment? A systematic review of reasons and predictors of discontinuation in fertility treatment

    NARCIS (Netherlands)

    Gameiro, S.; Boivin, J.; Peronace, L.; Verhaak, C.M.

    2012-01-01

    BACKGROUND Chances of achieving parenthood are high for couples who undergo fertility treatment. However, many choose to discontinue before conceiving. A systematic review was conducted to investigate patients' stated reasons for and predictors of discontinuation at five fertility treatment stages.

  15. Low body mass index compromises live birth rate in fresh transfer in vitro fertilization cycles: a retrospective study in a Chinese population.

    Science.gov (United States)

    Cai, Jiali; Liu, Lanlan; Zhang, Junwen; Qiu, Huiling; Jiang, Xiaoming; Li, Ping; Sha, Aiguo; Ren, Jianzhi

    2017-02-01

    To evaluate the effects of low body mass index (BMI) on in vitro fertilization (IVF) outcomes in fresh transfer cycles. Retrospective cohort study. University-affiliated hospital. A total of 4,798 cycles with conventional stimulation and fresh transfer in a single IVF center during the period 2013-2014. Low BMI (Live birth rate per fresh embryo transfer. Low BMI was associated with reduced live birth rates and increased miscarriage rates compared with normal weight, controlling for important covariates known to influence IVF outcomes. Patient age was the most potent confounder, causing a 10.5% reduction in the odds ratio (OR) for live birth between the groups compared. When an interaction term (age × BMI) was introduced, the OR for live birth was reduced in cycles of those aged ≥35 years compared with cycles of those aged 28-34 years, whereas the change in OR between cycles in those aged <28 and cycles in those aged 28-34 years was insignificant. Low BMI is associated with negative outcomes in fresh transfer cycles, especially for women of advanced age. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  16. Volcanic-plutonic connections and metal fertility of highly evolved magma systems: A case study from the Herberton Sn-W-Mo Mineral Field, Queensland, Australia

    Science.gov (United States)

    Cheng, Yanbo; Spandler, Carl; Chang, Zhaoshan; Clarke, Gavin

    2018-03-01

    Understanding the connection between the highly evolved intrusive and extrusive systems is essential to explore the evolution of high silicic magma systems, which plays an important role in discussions of planetary differentiation, the growth of continents, crustal evolution, and the formation of highly evolved magma associated Sn-W-Mo mineral systems. To discern differences between "fertile" and "non-fertile" igneous rocks associated with Sn-W-Mo mineralization and reveal the genetic links between coeval intrusive and extrusive rocks, we integrate whole rock geochemistry, geochronology and Hf isotope signatures of igneous zircons from contemporaneous plutonic and volcanic rocks from the world-class Herberton Mineral Field of Queensland, Australia. The 310-300 Ma intrusive rocks and associated intra-plutonic W-Mo mineralization formed from relatively oxidized magmas after moderate degrees of crystal fractionation. The geochemical and isotopic features of the coeval volcanic succession are best reconciled utilizing the widely-accepted volcanic-plutonic connection model, whereby the volcanic rocks represent fractionated derivatives of the intrusive rocks. Older intrusions emplaced at 335-315 Ma formed from relatively low fO2 magmas that fractionated extensively to produce highly evolved granites that host Sn mineralization. Coeval volcanic rocks of this suite are compositionally less evolved than the intrusive rocks, thereby requiring a different model to link these plutonic-volcanic sequences. In this case, we propose that the most fractionated magmas were not lost to volcanism, but instead were effectively retained at the plutonic level, which allowed further localized build-up of volatiles and lithophile metals in the plutonic environment. This disconnection to the volcanism and degassing may be a crucial step for forming granite-hosted Sn mineralization. The transition between these two igneous regimes in Herberton region over a ∼30 m.y. period is attributed to

  17. Population ageing and inter-generational relation in the MENA: what role for social policy?

    NARCIS (Netherlands)

    M. Meskoub (Mahmood)

    2017-01-01

    textabstractDeclining fertility and rising life expectancy combined with migration are changing the demographic landscape of the MENA. Earlier high fertility however will ensure a growing population in the next 20-30 years. Family structure is also changing, it is becoming smaller and of nuclear

  18. Socio-economic determinants of fertility in some countries of Asia.

    Science.gov (United States)

    Pathak, K B; Murty, P K

    1982-06-01

    An attempt is made in this analysis to determine the individual contribution of 6 factors--health variables, educational variables, variables showing status of women, economic variables, modernization variables, and family planning program performance variables--in determining the level of fertility on the basis of available data for 13 Asian countries. Path analysis and stepwise regression analysis were used. The pattern of the interrelationship between different categories of the variables which are affecting fertility and family planning performance are schematically represented in a chart. The model assumes that socioeconomic development of a country is a precondition for further mortality and fertility decline. The application of the model to any empirical situation calls for the determination of the indicators of the output variable (fertility) and other explanatory factors such as socioeconomic development, modernization, and health variables. For this study only 13 developing countries with 11 variables that are highly correlated with the fertility variables for the year 1975 were selected. 2 measures of fertility, i.e., total fertility rate (TFR) and crude birthrate (CBR) were taken for the purpose of the analysis and are denoted by Xo. The important background variables linked to fertility decline were literacy, urbanization, gross national product (GNP) per capita, and economically active female population in that order. Infant mortality and family planning were the most proximate variables to fertility. One of the reasons that fertility levels varied among the countries was that most of the countries have not as yet crossed the lower limits of the threshold zones with respect to most of the indicators. Except for 3 or 4 of the countries, none of the countries had entered the threshold zone for all the indicators. Particularly countries like Bangladesh, Nepal, and Pakistan were far below the lower limit of threshold zone in respect to all of the

  19. Is Wildlife Fertility Control Always Humane?

    OpenAIRE

    Hampton, Jordan O.; Timothy H. Hyndman; Anne Barnes; Teresa Collins

    2015-01-01

    Simple Summary There are various fertility control methods (modalities) currently available that aim to reduce the abundance of problematic free-ranging mammalian wildlife. Here, we propose that dissimilarities in the mechanism of action indicate these methods produce great variation in animal welfare outcomes. We present a framework to assist managers in minimising animal welfare risks. Abstract Investigation of fertility control techniques to reduce reproductive rates in wildlife population...

  20. Female fertility and longevity.

    Science.gov (United States)

    Mitteldorf, Joshua

    2010-03-01

    Does bearing children shorten a woman's life expectancy? Pleiotropic theories of aging predict that it should, and in particular, the Disposable Soma theory predicts unequivocally that this effect should be inescapable. But many demographic studies, historic and current, have found no such effect. In this context,the Caerphilly cohort study stands apart as the sole test that corroborates the theory. Why has this study found an effect that others fail to see? Their analysis is based on Poisson regression, a statistical technique that is accurate only if the underlying data are Poisson distributed.But the distribution of the number of children born to women in the Caerphilly data based departs strongly from Poisson at the high end. This makes the result overly sensitive to a handful of women with 15 children or more who lived before 1700. When these five women are removed from a database of more than 2,900, the Poisson regression no longer shows a significant result. Bilinear regression relating life span to fertility and date of birth results in a small positive coefficient for fertility, in agreement with the main trend of reported results.

  1. trategies for durum wheat fertilization

    Directory of Open Access Journals (Sweden)

    L. Plescuta

    2016-06-01

    Full Text Available Abstract. Durum wheat (Tr. durum Desf. ranks second in the world cereal production after common wheat. It differs from the other species with its high grain protein content, especially with gluten quality, which makes it suitable for producing spaghetti, macaroni, semolina flour and other products for the food industry. The purpose of this review was to summarize the results obtained in Bulgaria and in the world on the impact of mineral fertilization on yield and quality of durum wheat. All authors confirm that a significant increase of the grain yield in the last decades was achieved by both using new varieties and through optimal fertilization. Nitrogen as a nutrient is of great importance for wheat productivity. Nitrogen fertilization leads to stronger increase of leaf area, dry matter accumulation, content of protein and gluten. Accumulated nitrogen and phosphorus depend mainly on the formed dry matter. At low nitrogen rates yield increased at higher phosphorus level. Suppressant effect of high nitrogen and phosphorus rates on growth and development is emphasized in richer soil. A number of authors have found genotypic specificity regarding grain yield in dependence on the level of fertilization. Problems of genetically determined and improved grain quality under different durum wheat varieties are the subject of extensive research. The opinions of all authors are one-way for the positive influence of fertilization and in particular nitrogen on the technological quality parameters – protein content, wet and dry gluten, vitreoussness, carotenoids pigment, although the values vary significantly. The influence of fertilization is insignificant on the test weight.

  2. [Sexuality, fertility and pregnancy after kidney transplantation].

    Science.gov (United States)

    Kleinclauss, F; Timsit, M-O; Thuret, R

    2016-11-01

    To describe sexuality and fertility alterations secondary to chronic kidney disease and their outcomes after renal transplantation. An exhaustive systematic review of the scientific literature was performed in the Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of the following keywords: erectile dysfunction; impotence; sexuality; pregnancy; fertility; renal transplantation. Publications obtained were selected based on methodology, language, date of publication (last 10 years) and relevance. Prospective and retrospective studies, in English or French, review articles; meta-analysis and guidelines were selected and analyzed. This search found 706 articles. After reading titles and abstracts, 76 were included in the text, based on their relevance. The observed prevalence of erectile dysfunction is high in men with chronic kidney disease. The causes of erectile dysfunction are numbers and its origin is often multifactorial. Most of the time, kidney transplantation improves sexuality and the management of erectile dysfunction in transplanted men is similar to the general population. Improvement in sexuality in men and women after kidney transplantation may conduct to pregnancy. The outcomes of pregnancy after transplantation are quite good in absence of risk factors such as time to pregnancy less than 1 year after transplantation, uncontrolled high blood pressure, and decreased renal function of the graft. Adaptation of immunosuppression may be required to avoid any teratogenicity for the fetus. Kidney transplantation improves sexuality and fertility in men and women with chronic kidney disease. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. Efficacy of Kisspeptin-54 to Trigger Oocyte Maturation in Women at High Risk of Ovarian Hyperstimulation Syndrome (OHSS) During In Vitro Fertilization (IVF) Therapy

    Science.gov (United States)

    Abbara, Ali; Jayasena, Channa N.; Christopoulos, Georgios; Narayanaswamy, Shakunthala; Izzi-Engbeaya, Chioma; Nijher, Gurjinder M. K.; Comninos, Alexander N.; Peters, Deborah; Buckley, Adam; Ratnasabapathy, Risheka; Prague, Julia K.; Salim, Rehan; Lavery, Stuart A.; Bloom, Stephen R.; Szigeti, Matyas; Ashby, Deborah A.; Trew, Geoffrey H.

    2015-01-01

    Context: In vitro fertilization (IVF) treatment is an effective therapy for infertility, but can result in the potentially life-threatening complication, ovarian hyperstimulation syndrome (OHSS). Objective: This study aimed to investigate whether kisspeptin-54 can be used to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS. Setting and Design: This was a phase 2, multi-dose, open-label, randomized clinical trial of 60 women at high risk of developing OHSS carried out during 2013–2014 at Hammersmith Hospital IVF unit, London, United Kingdom. Intervention: Following a standard recombinant FSH/GnRH antagonist protocol, patients were randomly assigned to receive a single injection of kisspeptin-54 to trigger oocyte maturation using an adaptive design for dose allocation (3.2 nmol/kg, n = 5; 6.4 nmol/kg, n = 20; 9.6 nmol/kg, n = 15; 12.8 nmol/kg, n = 20). Oocytes were retrieved 36 h after kisspeptin-54 administration, assessed for maturation, and fertilized by intracytoplasmic sperm injection with subsequent transfer of one or two embryos. Women were routinely screened for the development of OHSS. Main Outcome Measure: Oocyte maturation was measured by oocyte yield (percentage of mature oocytes retrieved from follicles ≥ 14 mm on ultrasound). Secondary outcomes include rates of OHSS and pregnancy. Results: Oocyte maturation occurred in 95% of women. Highest oocyte yield (121%) was observed following 12.8 nmol/kg kisspeptin-54, which was +69% (confidence interval, −16–153%) greater than following 3.2 nmol/kg. At all doses of kisspeptin-54, biochemical pregnancy, clinical pregnancy, and live birth rates per transfer (n = 51) were 63, 53, and 45%, respectively. Highest pregnancy rates were observed following 9.6 nmol/kg kisspeptin-54 (85, 77, and 62%, respectively). No woman developed moderate, severe, or critical OHSS. Conclusion: Kisspeptin-54 is a promising approach to effectively and safely

  4. Communication and coping as predictors of fertility problem stress: cohort study of 816 participants who did not achieve a delivery after 12 months of fertility treatment

    DEFF Research Database (Denmark)

    Schmidt, L; Holstein, B E; Christensen, Ulla

    2005-01-01

    -up. Data were based on self-administered questionnaires measuring communication with partner and with other people, coping strategies: active-avoidance coping, active-confronting coping, passive-avoidance coping, meaning-based coping, and fertility problem stress. The study population included those...... for men, 3.69, 95% confidence interval 2.09-6.43). Active-avoidance coping (e.g. avoiding being with pregnant women or children, turning to work to take their mind off things) was a significant predictor of high fertility problem stress. Among men, high use of active-confronting coping (e.g. letting...... in the personal and marital domain. CONCLUSION: The study provides information about where to intervene with fertility patients in order to reduce their stress after medically unsuccessful treatment....

  5. Fertility in the Age of Demographic Maturity: An Essay

    Directory of Open Access Journals (Sweden)

    Anatole Romaniuk

    2010-01-01

    Full Text Available As humanity is moving into a new age of its demographic evolution, I call it demographic maturity, the emerging demographic configurations – generational sub-replacement fertility, advanced aging and potential population implosion – call for new ways of thinking about population and new policy approaches. While we live longer and healthier, we also reproduce less and less. We are stuck in a culture of low fertility. The strong motivations for foregoing motherhood are financial: a two-salary wage is better than one even for the higher middle class. No less important is the woman’s financial independence in a societal environment where marriage as an institution is under considerable stress. Motherhood is to be rewarded adequately for its highly important social role and it has to be sufficient to reassure potential mothers of their financial concerns. What is required is a more balanced resource allocation between production and reproduction. The old welfare type hand-outs like child bonuses do not work. Societies, particularly the rich, ought to realize that to raise fertility, even to generational replacement level, not only is a much greater financial effort called for but some of the tenants of the liberal economy need to be put into question to make room for social concerns such a renewal of generations, if they want to survive as national entities. This essay advocates a stationary population as the best response to challenges such as ecological health, national identity and cohesion, and possibly world peace.

  6. The population genetics of Pseudomonas aeruginosa isolates from different patient populations exhibits high-level host specificity.

    Directory of Open Access Journals (Sweden)

    Rosa van Mansfeld

    Full Text Available OBJECTIVE: To determine whether highly prevalent P. aeruginosa sequence types (ST in Dutch cystic fibrosis (CF patients are specifically linked to CF patients we investigated the population structure of P. aeruginosa from different clinical backgrounds. We first selected the optimal genotyping method by comparing pulsed-field gel electrophoresis (PFGE, multilocus sequence typing (MLST and multilocus variable number tandem-repeat analysis (MLVA. METHODS: Selected P. aeruginosa isolates (n = 60 were genotyped with PFGE, MLST and MLVA to determine the diversity index (DI and congruence (adjusted Rand and Wallace coefficients. Subsequently, isolates from patients admitted to two different ICUs (n = 205, from CF patients (n = 100 and from non-ICU, non-CF patients (n = 58, of which 19 were community acquired were genotyped with MLVA to determine distribution of genotypes and genetic diversity. RESULTS: Congruence between the typing methods was >79% and DIs were similar and all >0.963. Based on costs, ease, speed and possibilities to compare results between labs an adapted MLVA scheme called MLVA9-Utrecht was selected as the preferred typing method. In 363 clinical isolates 252 different MLVA types (MTs were identified, indicating a highly diverse population (DI  = 0.995; CI  = 0.993-0.997. DI levels were similarly high in the diverse clinical sources (all >0.981 and only eight genotypes were shared. MTs were highly specific (>80% for the different patient populations, even for similar patient groups (ICU patients in two distinct geographic regions, with only three of 142 ICU genotypes detected in both ICUs. The two major CF clones were unique to CF patients. CONCLUSION: The population structure of P. aeruginosa isolates is highly diverse and population specific without evidence for a core lineage in which major CF, hospital or community clones co-cluster. The two genotypes highly prevalent among Dutch CF patients appeared unique to CF patients

  7. The economics of fertility.

    Science.gov (United States)

    Loraine, J A

    1982-01-01

    The statement that economics and fertility are closely interrelated is a truism. The classical economists--Adam Smith, Thomas Malthus, Karl Marx, John Stuart Mill and John Maynard Keynes appreciated this fact, and their reviews are recounted and their prescience is assessed. Adam Smith (1723-1790) was primarily concerned with the desire of humankind to better his/her material conditions. Although he did not put forward a specific population policy, the tenet of his writing is pronatalist. Economic advantages would accrue to parents by the production of many children. Yet, underneath Smith's optimism, there was an apocalyptic vision of the distant future, i.e., the "steady state" when resources would be depleted or near exhaustion, when capital accumulation would have ceased, and living standards would be dropping vertiginously. In his 1st "Essay on Population" Malthus maintained that "the power of population is infinitely greater than the power of the earth to produce subsistence of men." Malthus can be complimented on his prescience. There is little question that the planet of today is grossly overpopulated and that a great gulf exists between numbers of people and their aspirations and the resources which the earth can provide for them. Malthus was particularly concerned about the population food dilemma, and that is still much in evidence in 1982. 2 concomitants of overpopulation--excessive urbanization and joblessness--could not be foreseen by Malthus. Marx did not deny the basic tenet promulgated by Malthus but to him this was simply an artifact of capitalist society which required "enormous reserves of proletarians" in order to maintain its odius system. Officially Communist governments remain in a Marxist straitjacket regarding the population issue. Mills approach was strongly antinatalist; he saw little need for an increase in human numbers. Mills was concerned that because of unlimited population growth and wealth the earth would lose much of its

  8. Reduced fertility in high-yielding dairy cows: are the oocyte and embryo in danger? Part II. Mechanisms linking nutrition and reduced oocyte and embryo quality in high-yielding dairy cows.

    Science.gov (United States)

    Leroy, J L M R; Van Soom, A; Opsomer, G; Goovaerts, I G F; Bols, P E J

    2008-10-01

    Dairy cow fertility has been declining during since the mid-80s and this has given rise to numerous scientific studies in which important parts of the pathogenesis are elucidated. Reduced oocyte and embryo quality are acknowledged as major factors in the widely described low conception rates and in the high prevalence of early embryonic mortality. Apart from the importance of the negative energy balance (NEB) and the associated endocrine and metabolic consequences, there is a growing attention towards the effect of the milk yield promoting diets which are rich in energy and protein. Starch-rich diets can improve the energy status and thus the ovarian activity in the early postpartum period but the oocyte and embryo quality can suffer from such insulinogenic diets. Supplementation of dietary fat has a similar dual effect with a beneficial stimulation of the ovarian steroid production while the oocyte and the embryo display an altered energy metabolism and excessive lipid accumulation. High-protein diets can elevate the ammonia and urea concentrations in the blood, leading to changed intrafollicular, oviductal and uterine environments. Oocytes and embryos are highly sensitive to such changes in their microenvironment, possibly leading to a disturbed maturation, fertilization or early cleavage. Several nutrition-linked mechanisms, through which oocyte and/or embryo quality can be affected in modern dairy cows, well after the period of NEB, are proposed and comprehensively reviewed in the present report.

  9. The organic fertilization in the onion cultivation

    Directory of Open Access Journals (Sweden)

    Roberto Llorente Villa

    2016-02-01

    Full Text Available The present work was developed in the UBPC “The Coast”, belonging to the Miscellaneous Crops Enterprise of Campechuela municipality, Granma province, during the period from November to March of the year 2010 – 2011. It was carried out in a reddish brown fersialitic soil, according with the new genetic classification of the soils of Cuba MINAGRI, (2000, with the objective of studying and evaluating the influence of different organic fertilizers in the growth, development and yield in the cultivation of onion, variety Texas Early Grain. For this reason it was necessary to work on blocks with 4 treatments and 4 replies. The treatments applied were: treatment 1 (vermicompost, treatment 2 (cow dung, treatment 3 (cachaça and treatment 4 (control, those were applied in a solid way. The growth variables that were evaluated were number of leaves, height of the plant, equatorial diameter, polar diameter and fresh weight of the bulb. The yield was also evaluated in t.ha-1 per treatment. High yields are achieved with the application of organic fertilizer, among 27 and 30 t.ha-1, this is an alternative for the sustainable production of this product which is highly demanded by the population.

  10. Comprehensive proteomic analysis of bovine spermatozoa of varying fertility rates and identification of biomarkers associated with fertility

    Directory of Open Access Journals (Sweden)

    Kaya Abdullah

    2008-02-01

    Full Text Available Abstract Background Male infertility is a major problem for mammalian reproduction. However, molecular details including the underlying mechanisms of male fertility are still not known. A thorough understanding of these mechanisms is essential for obtaining consistently high reproductive efficiency and to ensure lower cost and time-loss by breeder. Results Using high and low fertility bull spermatozoa, here we employed differential detergent fractionation multidimensional protein identification technology (DDF-Mud PIT and identified 125 putative biomarkers of fertility. We next used quantitative Systems Biology modeling and canonical protein interaction pathways and networks to show that high fertility spermatozoa differ from low fertility spermatozoa in four main ways. Compared to sperm from low fertility bulls, sperm from high fertility bulls have higher expression of proteins involved in: energy metabolism, cell communication, spermatogenesis, and cell motility. Our data also suggests a hypothesis that low fertility sperm DNA integrity may be compromised because cell cycle: G2/M DNA damage checkpoint regulation was most significant signaling pathway identified in low fertility spermatozoa. Conclusion This is the first comprehensive description of the bovine spermatozoa proteome. Comparative proteomic analysis of high fertility and low fertility bulls, in the context of protein interaction networks identified putative molecular markers associated with high fertility phenotype.

  11. [Impacts of urbanization on population development in China].

    Science.gov (United States)

    Zeng, Y

    1991-04-01

    Urbanization could make important contributions to the control of population growth in China, since urban populations have lower levels of fertility than do rural populations, and permanent migrants from rural to urban areas generally have even lower fertility levels. Population projections were made up to the middle of the next century assuming the presence and the absence of urbanization to illustrate the effect of urbanization on population size and the proportion of older people in the population. The scenario of urbanization shows a smaller population size and a higher proportion of old age population in rural areas than in urban areas. This situation would be favorable to economic growth, and the government would have less responsibility in caring for its old age population than if there were a larger proportion of urban aged. As the level of education is higher and health care provision is better in urban areas generally, urbanization would improve the quality of population. At the present time, fertility among temporary migrants is still high as they are under the influence of cultural factors and some of them migrated temporarily to escape the birth control program of their original place of residence. Policy regulations and programs are necessary in order for temporary migrant workers to abide by the birth control regulations of the place of destination and to restrict their fertility. Long-term settlements of young rural migrants in cities or towns will contribute to urban economic developments and reduce their fertility.

  12. The level and patterns of fertility among women in Kersa Demographic Surveillance and Health Research Center (KDS-HRC) Field site, Kersa District, East Ethiopia.

    Science.gov (United States)

    Zelalem, Desalew; Semahegn, Agumasie; Tesfaye, Gezahegn; Sileshi, Balewgize

    2015-01-01

    Fertility is one of the three principal components of population dynamics. High fertility and rapid population growth exert negative influences on economic and social development. This study was aimed to estimate the level and trends of fertility among (15-49 years) old women in kersa demographic surveillance and health research center, kersa district Eastern Ethiopia. The study was conducted at kersa demographic surveillance and health research center in kersa district, Eastern Ethiopia. The study utilized five years follow up data (2008-2012). All women (15 to 49 years old) who have been living at kersa demographic surveillance and health research center in kersa district from 2008 to 2012 were included in the analysis to estimate the level and pattern of fertility. Descriptive statistics was computed to determine level and pattern of fertility. Age specific fertility rate was highest in women of the age group 25-29 years old (233.2 per 1000 women in 2008; 205.8 per 1000 women in 2009; 279.0 per 1000 women in 2010; 186.6 per 1000 women in 2011 and 198.5 per 1000 women in 2012) in five consecutive years from 2008 to 2012. Total fertility rate didn't show any significant decline during the study period, i.e., 4.3, 4.5, 4.9, 3.5, 4.0 live births per woman throughout her reproductive period (15-49) years old in 2008, 2009, 2010, 2011 and 2012, respectively. On the other hand, general fertility rate declined from 110.3 births per 1000 women in 2008 to 95.9 per 1000 women in the reproductive age in 2012. The total fertility rate was found to be relatively high. Fertility rate is higher in rural residents and illiterate women than in urban residents and literate women. Strong information, education, communication and behavior change communication on family planning should be designed and implemented to prevent unwanted fertility.

  13. High genetic diversity and low population structure in Porter's sunflower (Helianthus porteri).

    Science.gov (United States)

    Gevaert, Scott D; Mandel, Jennifer R; Burke, John M; Donovan, Lisa A

    2013-01-01

    Granite outcrops in the southeastern United States are rare and isolated habitats that support edaphically controlled communities dominated by herbaceous plants. They harbor rare and endemic species that are expected to have low genetic variability and high population structure due to small population sizes and their disjunct habitat. We test this expectation for an annual outcrop endemic, Helianthus porteri (Porter's sunflower). Contrary to expectation, H. porteri has relatively high genetic diversity (H e = 0.681) and relatively low genetic structure among the native populations (F ST = 0.077) when compared to 5 other Helianthus species (N = 288; 18 expressed sequence tag-SSR markers). These findings suggest greater gene flow than expected. The potential for gene flow is supported by the analysis of transplant populations established with propagules from a common source in 1959. One population established close to a native population (1.5 km) at the edge of the natural range is genetically similar to and shares rare alleles with the adjacent native population and is distinct from the central source population. In contrast, a transplant population established north of the native range has remained similar to the source population. The relatively high genetic diversity and low population structure of this species, combined with the long-term success of transplanted populations, bode well for its persistence as long as the habitat persists.

  14. Simple vaginal trachelectomy as a fertility-sparing treatment to manage high-grade dyskaryosis following multiple large loop excision of the transformation zone.

    Science.gov (United States)

    Scrivener, Claire Grace; Gornall, Robert; Rolland, Philip

    2016-06-28

    A 34-year-old nullipara, wishing to start a family, presented to colposcopy clinic. Her most recent cervical cytology result showed high-grade dyskaryosis. Having undergone four large loop excisions of the transformation zone during the past 6 years, this woman had no remaining vaginal cervix. In order to excise presumed high-grade cervical intraepithelial neoplasia while mitigating obstetric risk, she underwent a simple vaginal trachelectomy and isthmic cerclage. 6 months later, the patient had a negative test of cure. 7 months following surgery she became pregnant naturally. At 29 weeks she had antenatal sepsis of unknown cause, which was treated with intravenous antibiotics. She delivered by caesarean section at 37 weeks and now has a healthy child. This report will discuss the obstetric impact of colposcopic treatment, and simple vaginal trachelectomy as a fertility-sparing treatment option for women who have had multiple loop excision procedures to treat premalignant lesions. 2016 BMJ Publishing Group Ltd.

  15. High-performance coherent population trapping clock with polarization modulation

    CERN Document Server

    Yun, Peter; Calosso, Claudio Eligio; Micalizio, Salvatore; François, Bruno; Boudot, Rodolphe; Guérandel, Stéphane; de Clercq, Emeric

    2016-01-01

    We demonstrate a vapor cell atomic clock prototype based on continuous-wave (CW) interrogation and double-modulation coherent population trapping (DM-CPT) technique. The DM-CPT technique uses a synchronous modulation of polarization and relative phase of a bi-chromatic laser beam in order to increase the number of atoms trapped in a dark state, i.e. a non-absorbing state. The narrow resonance, observed in transmission of a Cs vapor cell, is used as a narrow frequency discriminator in an atomic clock. A detailed characterization of the CPT resonance versus numerous parameters is reported. A short-term frequency stability of $3.2 \\times 10^{-13} \\tau^{-1/2}$ up to 100 s averaging time is measured. These performances are more than one order of magnitude better than industrial Rb clocks and comparable to those of best laboratory-prototype vapor cell clocks. The noise budget analysis shows that the short and mid-term frequency stability is mainly limited by the power fluctuations of the microwave used to generate ...

  16. Glaucoma screening in a high-risk population.

    Science.gov (United States)

    Vistamehr, Setareh; Shelsta, Heather N; Palmisano, Philip C; Filardo, Giovanni; Bashford, Kent; Chaudhri, Kamran; Forster, Susan H; Shafranov, George; Bruce Shields, M

    2006-12-01

    To evaluate a screening protocol for detection of individuals with a higher risk of chronic open angle glaucoma for which a complete glaucoma evaluation is indicated. African Americans over 40 years of age in New Haven, CT. In the screening phase, volunteers filled out a questionnaire and underwent measurements of visual acuity, intraocular pressure (IOP) with a Tono-Pen and visual field with Frequency Doubling Technology. Participants were categorized into "glaucoma likely" or "unlikely," but all were encouraged to follow up with a free complete glaucoma exam, which included applanation tonometry, pachymetry, visual fields with a Humphrey Visual Field Analyzer, gonioscopy, and fundoscopy. Based on the latter exam, patients were categorized into "glaucoma likely" (suspects and confirmed glaucoma) or "unlikely" groups. One hundred eighty-four subjects completed both phases of the study and 76 of 93 patients (82%) who were classified as "glaucoma likely" in the final exam, were also classified as "glaucoma likely" in the screening. Adjusted analysis revealed family history of glaucoma in first degree relatives and screening IOP > 21 mm Hg to have statistically significant associations with the final impression of "glaucoma likely." A combination of these findings gave an overall sensitivity of 81.7% with a specificity of 55%. In the study population, the combination of an IOP > 21 mm Hg and history of glaucoma in a first degree relative allowed the identification of a significant percentage of individuals with a higher risk of chronic open angle glaucoma, for which a complete glaucoma examination is indicated.

  17. Hypertensive patients and diabetes : A high-risk population

    NARCIS (Netherlands)

    Bilo, HJG; Gans, ROB

    1998-01-01

    Rising worldwide rates of diabetes mellitus heighten the need to maintain adequate metabolic control in diabetic patients and to control for other cardiovascular risk factors, such as lipid profile disturbances, high blood pressure, and smoking habits. This is especially the case in diabetic

  18. Fear of Success: The Distribution, Correlates, Reliability and Consequences for Fertility of Fear of Success Among Respondents in a Metropolitan Survey Population.

    Science.gov (United States)

    Moore, Kristin A.

    This study was designed to extend discussion of fear of success beyond the college population, using Horner's original coding scheme to examine the thematic imagery of TAT stories told by a cross-section of the public during a survey interview. The data collected from this sample of the general public contrasted in several ways with data gathered…

  19. [Fertility changes in women working in greenhouses].

    Science.gov (United States)

    Rosano, A; Gemelli, V; Giovannelli, Cinzia; Paciotti, G; Sabatucci, A; Spagnolo, A

    2009-01-01

    Greenhouse workers (GW) are exposed to environmental contaminants, including pesticides, that may not only cause known immediate effects such as acute poisoning, but also long-term effects related to chronic exposure to low dosages, a problem that has not been extensively studied This study investigated the relationship between fertility changes and exposure to pesticides in a group of women working in greenhouses. The analysis is based on a retrospective cohort of 145 women working in greenhouses located in the province of Latina, Lazio Region, Italy, who were exposed to pesticides at the time of their first pregnancy. Information on health status, lifestyle, work activity, reproductive history and some confounding factors (age, smoking, alcohol abuse, drug consumption) were collected using a questionnaire. Exposure to pesticides was classified in two levels (high or low) according to the work task and the length of exposure. Changes in fertility were measured in terms of time to pregnancy (TTP), that is the number of non-contraceptive cycles that it takes a couple to conceive. A control group was selected among public administration employees in the same province. The difference in average TTP between exposed and non-exposed groups was analysed by using Student t-test. A Cox proportional hazard model was used to compare TTP between the two groups after correction for confounding factors. In the high-level exposure group average TTP was 10.8 months (+/- 2.0), among the non-exposed average TTP was 6.2 months (+/- 1.0). The difference between exposed and non-exposed was thus 4.6 months (p<0.05). Comparison of the distribution of TTP between the high-level exposure group and nonexposed resulted in a hazard ratio of 1.27 (I.C. 95%: 1.03-1.79); the same analysis using the low-level exposure group and non-exposed group yielded a hazard ratio of 1.12 (I.C. 95%: 0.67-1.87). The study showed reduced fertility, in terms of TTP, in the population exposed to pesticides. Among

  20. Determinants of adolescent fertility in Malawi | Palamuleni | Gender ...

    African Journals Online (AJOL)

    High adolescent fertility is recognized as a global challenge given its adverse consequences. As such understanding the factors that influence adolescent fertility is critical to addressing this challenge. This study aims at examining the causes of adolescent fertility in Malawi using the 2010 Malawi Demographic and Health ...

  1. Effect of fertilizer treatment on the chemical and functional properties ...

    African Journals Online (AJOL)

    The effect of different levels of fertilizer treatment on some chemical and functional properties of high quality cassava flour (HQCF) was investigated. Cassava cultivar (TMS/98/0505) was intercropped with maize (TZSR-Y) and fertilized with urea at 4 weeks after planting. The fertilizer was applied at the -1 rates of 0 (control), ...

  2. High risk of sleep disordered breathing in the enuresis population.

    Science.gov (United States)

    Bascom, Alexandra; Penney, Todd; Metcalfe, Mike; Knox, Aaron; Witmans, Manisha; Uweira, Trina; Metcalfe, Peter Douglas

    2011-10-01

    Enuresis is 1 of the most common complaints facing pediatric urologists and it has significant implications with respect to quality of life. Although the pathophysiology is incompletely understood, there is growing evidence that sleep disordered breathing in children, including obstructive sleep apnea, has a fundamental role. There are also potentially fundamental differences between monosymptomatic enuresis, which may be a sleep disorder, and nonmonosymptomatic enuresis, which may relate to a primary bladder storage problem. We prospectively evaluated the incidence of obstructive sleep apnea in patients with enuresis and analyzed differences between patients with monosymptomatic and nonmonosymptomatic enuresis. A total of 69 children with enuresis were given 3 validated questionnaires to complete, including the Dysfunctional Voiding and Incontinence Symptom Score, the Obstructive Sleep Apnea Quality of Life survey and the Modified Pediatric Sleep Questionnaire. The Dysfunctional Voiding and Incontinence Symptom Score quantifies patient dysfunctional voiding habits. The Obstructive Sleep Apnea Quality of Life survey evaluates patient quality of life in regard to obstructive sleep apnea and its effects. Modified Pediatric Sleep Questionnaire results describe the severity of patient sleep disturbances. The mean Obstructive Sleep Apnea Quality of Life Survey score was 43 and 54% of patients had positive Modified Pediatric Sleep Questionnaire results, indicating that obstructive sleep apnea was prevalent in our population. Those with enuresis and daytime incontinence were significantly more likely to have sleep disordered breathing than those with monosymptomatic enuresis (p enuresis. All pediatric health care providers should be aware of this risk. The risk may be magnified in patients with concomitant daytime incontinence. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  3. Specific Abilities May Increment Psychometric g for High Ability Populations

    Science.gov (United States)

    2016-04-14

    1. REPORT DATE (DD-MM-YYYY) 04/2016 2. REPORT TYPE Final 3. DATES COVERED (From - To) 04/2015 – 08/2016 4. TITLE AND SUBTITLE...higher ability groups. Intelligence, 23, 45-57. Lynn, R. (1990). Does Spearman’s g decline at high levels? Some evidence from Scotland . The Journal...1979). Use of the position analysis questionnaire for establishing the job component validity of tests. Journal of Applied Psychology, 64, 51

  4. Indicators of poor dietary habits in a high risk population.

    Science.gov (United States)

    Rogers, M A; Simon, D G; Zucker, L B; Mackessy, J S; Newman-Palmer, N B

    1995-04-01

    This study was conducted to determine whether individuals attending an urban outpatient clinic met the National Health Promotion and Disease Prevention nutritional objectives and to assess factors associated with poor dietary habits. Individuals who attended the general medicine outpatient clinic at the State University of New York Health Science Center in Syracuse were interviewed using an expanded version of the Health Habits and History Questionnaire. Usual dietary intake, medical history, occupation, stress, physical activity, tobacco use and other life-style factors were recorded. Of particular interest were the percentage of calories from fat in the diet and whether individuals consumed the daily requirements of the base-foods in the USDA Pyramid (grains, vegetables and fruits). Unconditional logistic regression was used to determine odds ratios (OR) and 95% confidence intervals for variables associated with high fat consumption and low consumption of vegetables, fruit and high-fiber grains. None of the patients met the minimal recommended daily servings for the three base-food categories combined (grains, vegetables and fruits) and 84% of subjects had fat intakes which constituted over 30% of daily energy intake. Individuals with less education, who were disabled or unemployed, and who participated in little physical activity were twice as likely to have poor dietary habits (i.e. low consumption of vegetables, fruit, and/or high-fiber grains) as other subjects (p or = 50 years of age). Nonwhite subjects were less likely to consume high-fiber grains and whole-wheat breads than white patients (p = 0.04). Nutritional screening should be considered for all patients attending similar inner-city general medicine clinics, regardless of the primary diagnosis in order to provide early dietary intervention. In particular, young adults, the unemployed, and the disabled should not be overlooked.

  5. Model comparison on genomic predictions using high-density markers for different groups of bulls in the Nordic Holstein population.

    Science.gov (United States)

    Gao, H; Su, G; Janss, L; Zhang, Y; Lund, M S

    2013-07-01

    This study compared genomic predictions based on imputed high-density markers (~777,000) in the Nordic Holstein population using a genomic BLUP (GBLUP) model, 4 Bayesian exponential power models with different shape parameters (0.3, 0.5, 0.8, and 1.0) for the exponential power distribution, and a Bayesian mixture model (a mixture of 4 normal distributions). Direct genomic values (DGV) were estimated for milk yield, fat yield, protein yield, fertility, and mastitis, using deregressed proofs (DRP) as response variable. The validation animals were split into 4 groups according to their genetic relationship with the training population. Groupsmgs had both the sire and the maternal grandsire (MGS), Groupsire only had the sire, Groupmgs only had the MGS, and Groupnon had neither the sire nor the MGS in the training population. Reliability of DGV was measured as the squared correlation between DGV and DRP divided by the reliability of DRP for the bulls in validation data set. Unbiasedness of DGV was measured as the regression of DRP on DGV. The results indicated that DGV were more accurate and less biased for animals that were more related to the training population. In general, the Bayesian mixture model and the exponential power model with shape parameter of 0.30 led to higher reliability of DGV than did the other models. The differences between reliabilities of DGV from the Bayesian models and the GBLUP model were statistically significant for some traits. We observed a tendency that the superiority of the Bayesian models over the GBLUP model was more profound for the groups having weaker relationships with training population. Averaged over the 5 traits, the Bayesian mixture model improved the reliability of DGV by 2.0 percentage points for Groupsmgs, 2.7 percentage points for Groupsire, 3.3 percentage points for Groupmgs, and 4.3 percentage points for Groupnon compared with GBLUP. The results showed that a Bayesian model with intense shrinkage of the explanatory

  6. Interactions between observer and stimuli fertility status: Endocrine and perceptual responses to intrasexual vocal fertility cues.

    Science.gov (United States)

    Ostrander, Grant M; Nathan Pipitone, R; Shoup-Knox, Melanie L

    2017-12-22

    Both men and women find female voices more attractive at higher fertility times in the menstrual cycle, suggesting the voice is a cue to fertility and/or hormonal status. Preference for fertile females' voices provides males with an obvious reproduction advantage, however the advantage for female listeners is less clear. One possibility is that attention to the fertility status of potential rivals may enable women to enhance their own reproductive strategies through intrasexual competition. If so, the response to having high fertility voices should include hormonal changes that promote competitive behavior. Furthermore, attention and response to such cues should vary as a function of the observer's own fertility, which influences her ability to compete for mates. The current study monitored variation in cortisol and testosterone levels in response to evaluating the attractiveness of voices of other women. All 33 participants completed this task once during ovulation then again during the luteal phase. The voice stimuli were recorded from naturally cycling women at both high and low fertility, and from women using hormonal birth control. We found that listeners rated high fertility voices as more attractive compared to low fertility, with the effect being stronger when listeners were ovulating. Testosterone was elevated following voice ratings suggesting threat detection or the anticipation of competition, but no stress response was found. Copyright © 2017. Published by Elsevier Inc.

  7. A long-term nitrogen fertilizer gradient has little effect on soil organic matter in a high-intensity maize production system.

    Science.gov (United States)

    Brown, Kimberly H; Bach, Elizabeth M; Drijber, Rhae A; Hofmockel, Kirsten S; Jeske, Elizabeth S; Sawyer, John E; Castellano, Michael J

    2014-04-01

    Global maize production alters an enormous soil organic C (SOC) stock, ultimately affecting greenhouse gas concentrations and the capacity of agroecosystems to buffer climate variability. Inorganic N fertilizer is perhaps the most important factor affecting SOC within maize-based systems due to its effects on crop residue production and SOC mineralization. Using a continuous maize cropping system with a 13 year N fertilizer gradient (0-269 kg N ha(-1) yr(-1)) that created a large range in crop residue inputs (3.60-9.94 Mg dry matter ha(-1) yr(-1)), we provide the first agronomic assessment of long-term N fertilizer effects on SOC with direct reference to N rates that are empirically determined to be insufficient, optimum, and excessive. Across the N fertilizer gradient, SOC in physico-chemically protected pools was not affected by N fertilizer rate or residue inputs. However, unprotected particulate organic matter (POM) fractions increased with residue inputs. Although N fertilizer was negatively linearly correlated with POM C/N ratios, the slope of this relationship decreased from the least decomposed POM pools (coarse POM) to the most decomposed POM pools (fine intra-aggregate POM). Moreover, C/N ratios of protected pools did not vary across N rates, suggesting little effect of N fertilizer on soil organic matter (SOM) after decomposition of POM. Comparing a N rate within 4% of agronomic optimum (208 kg N ha(-1) yr(-1)) and an excessive N rate (269 kg N ha(-1) yr(-1)), there were no differences between SOC amount, SOM C/N ratios, or microbial biomass and composition. These data suggest that excessive N fertilizer had little effect on SOM and they complement agronomic assessments of environmental N losses, that demonstrate N2 O and NO3 emissions exponentially increase when agronomic optimum N is surpassed. © 2014 John Wiley & Sons Ltd.

  8. [Fertility and mortality in the urban agglomeration of Banyo (Cameroon): the influence of venereal diseases].

    Science.gov (United States)

    Hurault, J

    1983-01-01

    The demographic situation in the city of Banyo, Cameroon, is described for the period 1952-1976 using survey and census data. This city was characterized by a large slave population, particularly in the nineteenth century, and slavery remained common up to the 1960s. The consequences of slavery, including disruption of family life, concubinage, and high rates of venereal disease, are noted. Fertility and mortality differences among the slave and free populations are analyzed by sex. (summary in ENG, SPA)

  9. Targeting Nitrous Oxide Reduction Efforts Using Crop-Specific, High-Resolution Emission Estimates from Synthetic Fertilizer

    Science.gov (United States)

    Gerber, J. S.; West, P. C.; Carlson, K. M.; Garcia de Cortazar-Atauri, I.; Launay, M.; Makowski, D.; Mueller, N. D.; O'Connell, C.

    2014-12-01

    Changes in global weather patterns are projected to have important impacts on regional food security. These impacts can be substantial, but how do they compare to other drivers of food supply vulnerability, including decreasing stocks, changing trade patterns, concentration of production, and changing demand patterns? We use multi-year global datasets of yield and area for staple crops to assess relationships between metrics of drought derived from high-resolution gridded weather data and crop yields. We then evaluate how these metrics are changing over time, and compare the resulting change in the likelihood of regional yield reduction events to other systemic factors.

  10. Fertility and Modernity

    OpenAIRE

    Enrico Spolaore; Romain Wacziarg

    2014-01-01

    We investigate the historical dynamics of the decline in fertility in Europe and its relation to measures of cultural and ancestral distance. We test the hypothesis that the decline of fertility was associated with the diffusion of social and behavioral changes from France, in contrast with the spread of the Industrial Revolution, where England played a leading role. We argue that the diffusion of the fertility decline and the spread of industrialization followed different patterns because so...

  11. Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

    Directory of Open Access Journals (Sweden)

    Kelly A. Nelson

    2012-01-01

    Full Text Available Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S, 0-0-25-17, 3-18-18-0, and 5-0-20-13 and additive rates (2.2, 8.8, and 17.6 kg K ha−1 on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ha−1 in a high-yield, weed-free environment in 2004, but fertilizer additives reduced yield up to 470 kg ha−1 in a low-yield year (2005 depending on the K source and rate. At Portageville, K-fertilizer additives increased grain yield from 700 to 1160 kg ha−1 compared to diammonium sulfate, depending on the K source and rate. At Malden, there was no yield response to K sources. Differences in leaf tissue K (P=0.03, S (P=0.03, B (P=0.0001, and Cu (P=0.008 concentrations among treatments were detected 14 d after treatment at Novelty and Malden. Tank mixtures of K-fertilizer additives with glyphosate may provide an option for foliar K applications.

  12. Data Driven Approach for High Resolution Population Distribution and Dynamics Models

    Energy Technology Data Exchange (ETDEWEB)

    Bhaduri, Budhendra L [ORNL; Bright, Eddie A [ORNL; Rose, Amy N [ORNL; Liu, Cheng [ORNL; Urban, Marie L [ORNL; Stewart, Robert N [ORNL

    2014-01-01

    High resolution population distribution data are vital for successfully addressing critical issues ranging from energy and socio-environmental research to public health to human security. Commonly available population data from Census is constrained both in space and time and does not capture population dynamics as functions of space and time. This imposes a significant limitation on the fidelity of event-based simulation models with sensitive space-time resolution. This paper describes ongoing development of high-resolution population distribution and dynamics models, at Oak Ridge National Laboratory, through spatial data integration and modeling with behavioral or activity-based mobility datasets for representing temporal dynamics of population. The model is resolved at 1 km resolution globally and describes the U.S. population for nighttime and daytime at 90m. Integration of such population data provides the opportunity to develop simulations and applications in critical infrastructure management from local to global scales.

  13. Nutritional knowledge and dietary habits survey in high school population.

    Science.gov (United States)

    Milosavljević, Dragana; Mandić, Milena L; Banjari, Ines

    2015-03-01

    During adolescence, young people are in a sensitive transition period when they gradually take over the responsibility for their own eating habits, health attitudes and behaviours and create lifelong habits so it is essential that they adopt healthy habits according to dietary recommendations. Knowledge is one of the factors necessary for the changes in dietary habits. The'objective of this study was to gain insight in nutritional knowledge and dietary habits of adolescents. The sample included 117 adolescents aged 17-19 years. Self-administered, anonymous questionnaire, representing modified version of General Nutrition Knowledge Questionnaire was used to assess general characteristics, nutritional knowledge about nutrients, dietary recommendations, sources of nutrients, diet-disease relationship, and dietary habits. Less than one third of adolescents showed satisfactory knowledge, but boys, adolescents from rural environment and overweight adolescents showed significantly lower knowledge unlike others. Meal skipping was present habit, especially for breakfast consumption. Especially high consumption of meat and meat products was noted for boys, while fruit and vegetables for girls. Fad dieting was quite practiced habit, especially in girls and overweight adolescents. Among girls, high consumption of sweets was confirmed, while boys showed high consumption of soft drinks. Television presents the main source of infor- mation about nutrition for adolescents. Collected data shows similarity with other research in Europe and North America that confirm strong influence of globalization and fast spread of unhealthy habits. The results pointed out weak spots in nutritional knowledge and revealed unhealthy eating habits. This information is necessary for the development of new approaches to modulate their knowledge and consequently act on their behaviour. Behavioral changes would include higher number of meals per day, regular breakfast consumption, higher intake of fish

  14. Different gonadotropin releasing hormone agonist doses for the final oocyte maturation in high-responder patients undergoing in vitro fertilization/intra-cytoplasmic sperm injection

    Directory of Open Access Journals (Sweden)

    Emre Goksan Pabuccu

    2015-01-01

    Full Text Available Context: Efficacy of gonadotropin releasing hormone agonists (GnRH-a for ovulation in high-responders. Aims: The aim of the current study is to compare the impact of different GnRH-a doses for the final oocyte maturation on cycle outcomes and ovarian hyperstimulation syndrome (OHSS rates in high-responder patients undergoing ovarian stimulation. Settings And Designs: Electronic medical records of a private in vitro fertilization center, a retrospective analysis. Subjects and Methods: A total of 77 high-responder cases were detected receiving GnRH-a. Group I consisted of 38 patients who received 1 mg of agonist and Group II consisted of 39 patients who received 2 mg of agonist. Statistical Analysis: In order to compare groups, Student′s t-test, Mann-Whitney U-test, Pearson′s Chi-square test or Fisher′s exact test were used where appropriate. A P < 0.05 was considered as statistically significant. Result: Number of retrieved oocytes (17.5 vs. 15.0, P = 0.510, implantation rates (46% vs. 55.1%, P = 0.419 and clinical pregnancy rates (42.1% vs. 38.5%, P = 0.744 were similar among groups. There were no mild or severe OHSS cases detected in Group I. Only 1 mild OHSS case was detected in Group II. Conclusion: A volume of 1 or 2 mg leuprolide acetate yields similar outcomes when used for the final oocyte maturation in high-responder patients.

  15. Warm and Fertile Sub-Humid Conditions Enhance Litterfall to Sustain High Soil Respiration Fluxes in a Mediterranean Cork Oak Forest

    Directory of Open Access Journals (Sweden)

    Lobna Zribi

    2015-08-01

    Full Text Available Soil respiration is a major component of the global carbon budget and Mediterranean ecosystems have usually been studied in locations with shallow soils, mild temperatures, and a prolonged dry season. This study investigates seasonal soil respiration rates and underlying mechanisms under wetter, warmer, and more fertile conditions in a Mediterranean cork oak forest of Northern Tunisia (Africa, acknowledged as one of the most productive forests in the Mediterranean basin. We applied a soil respiration model based on soil temperature and relative water content and investigated how ecosystem functioning under these favorable conditions affected soil carbon storage through carbon inputs to the soil litter. Annual soil respiration rates varied between 1774 gC m−2 year−1 and 2227 gC m−2 year−1, which is on the highest range of observations under Mediterranean climate conditions. We attributed this high soil carbon flux as a response to favorable temperatures and soil water content, but this could be sustained only by a small carbon allocation to roots (root/shoot ratio = 0.31–0.41 leading to a large allocation to leaves with a multiannual leaf production, enhanced annual twig elongation (11.5–28.5 cm with a reduced leaf life span (<1 year maintaining a low LAI (1.68–1.88 and generating a high litterfall (386–636 gC m−2 year−1. Thus, the favorable climatic and edaphic conditions experienced by these Mediterranean cork oak forests drove high soil respiration fluxes which balanced the high carbon assimilation leading to a relatively small overall contribution (10.96–14.79 kgC m−2 to soil carbon storage.

  16. A high dietary glycemic index increases total mortality in a Mediterranean population at high cardiovascular risk.

    Directory of Open Access Journals (Sweden)

    Itandehui Castro-Quezada

    Full Text Available OBJECTIVE: Different types of carbohydrates have diverse glycemic response, thus glycemic index (GI and glycemic load (GL are used to assess this variation. The impact of dietary GI and GL in all-cause mortality is unknown. The objective of this study was to estimate the association between dietary GI and GL and risk of all-cause mortality in the PREDIMED study. MATERIAL AND METHODS: The PREDIMED study is a randomized nutritional intervention trial for primary cardiovascular prevention based on community-dwelling men and women at high risk of cardiovascular disease. Dietary information was collected at baseline and yearly using a validated 137-item food frequency questionnaire (FFQ. We assigned GI values of each item by a 5-step methodology, using the International Tables of GI and GL Values. Deaths were ascertained through contact with families and general practitioners, review of medical records and consultation of the National Death Index. Cox regression models were used to estimate multivariable-adjusted hazard ratios (HR and their 95% CI for mortality, according to quartiles of energy-adjusted dietary GI/GL. To assess repeated measures of exposure, we updated GI and GL intakes from the yearly FFQs and used Cox models with time-dependent exposures. RESULTS: We followed 3,583 non-diabetic subjects (4.7 years of follow-up, 123 deaths. As compared to participants in the lowest quartile of baseline dietary GI, those in the highest quartile showed an increased risk of all-cause mortality [HR = 2.15 (95% CI: 1.15-4.04; P for trend  = 0.012]. In the repeated-measures analyses using as exposure the yearly updated information on GI, we observed a similar association. Dietary GL was associated with all-cause mortality only when subjects were younger than 75 years. CONCLUSIONS: High dietary GI was positively associated with all-cause mortality in elderly population at high cardiovascular risk.

  17. Is climate change affecting wolf populations in the high arctic?

    Energy Technology Data Exchange (ETDEWEB)

    Mech, L.D. [Northern Prairie Wildlife Research Center, Biological Resources Division, U.S. Geological Survey, 8711-37th St., SE, 58401-7317 Jamestown, North Dakota (United States)

    2004-11-01

    Global climate change may affect wolves in Canadas High Arctic (80{sup o} N) acting through three trophic levels (vegetation, herbivores, and wolves). A wolf pack dependent on muskoxen and arctic hares in the Eureka area of Ellesmere Island denned and produced pups most years from at least 1986 through 1997. However, when summer snow covered vegetation in 1997 and 2000 for the first time since records were kept, halving the herbivore nutrition-replenishment period, muskox and hare numbers dropped drastically, and the area stopped supporting denning wolves through 2003. The unusual weather triggering these events was consistent with global-climate-change phenomena.

  18. The Effect of Elevated CO2 and Increased Temperature on in Vitro Fertilization Success and Initial Embryonic Development of Single Male:Female Crosses of Broad-Cast Spawning Corals at Mid- and High-Latitude Locations

    Directory of Open Access Journals (Sweden)

    Miriam Schutter

    2015-05-01

    Full Text Available The impact of global climate change on coral reefs is expected to be most profound at the sea surface, where fertilization and embryonic development of broadcast-spawning corals takes place. We examined the effect of increased temperature and elevated CO2 levels on the in vitro fertilization success and initial embryonic development of broadcast-spawning corals using a single male:female cross of three different species from mid- and high-latitude locations: Lyudao, Taiwan (22° N and Kochi, Japan (32° N. Eggs were fertilized under ambient conditions (27 °C and 500 μatm CO2 and under conditions predicted for 2100 (IPCC worst case scenario, 31 °C and 1000 μatm CO2. Fertilization success, abnormal development and early developmental success were determined for each sample. Increased temperature had a more profound influence than elevated CO2. In most cases, near-future warming caused a significant drop in early developmental success as a result of decreased fertilization success and/or increased abnormal development. The embryonic development of the male:female cross of A. hyacinthus from the high-latitude location was more sensitive to the increased temperature (+4 °C than the male:female cross of A. hyacinthus from the mid-latitude location. The response to the elevated CO2 level was small and highly variable, ranging from positive to negative responses. These results suggest that global warming is a more significant and universal stressor than ocean acidification on the early embryonic development of corals from mid- and high-latitude locations.

  19. Agronomic performance of male-sterile and fertile maize genotypes at two plant populations Performace agronômica de genótipos macho-estéreis e férteis de milho em duas densidades de semeadura

    Directory of Open Access Journals (Sweden)

    Luís Sangoi

    1996-12-01

    Full Text Available This experiment was conducted in 1994 at Ames, Iowa, US to test whether cytoplasmic male-sterility can be used to decrease barrenness and to increase grain yield of maize at two plant populations. Four genotypes were tested: a hybrid (NK 6330 and an inbred, wifh sterile and fertile counterparts. Each genotype owas evaluated at plant populations equivalent to 25,000 and 75,000 pl. ha-1. Hybrids produced higher grain yield than inbreds at both plant populations. Gram yield was higher at 75,000 than at 25,000 pl. ha-1. No difference in gram yield, number of ears per plant, number of grains per ear, tassel length, and tassel number of branches was found between sterile and fertile counterparts of the inbred and hybrid, regardiess of plant population. Fertile genotypes bore heavier tassels at anthesis than their sterile counterparts. Adequate precipitation distribution and high fertility level in the soil probably decreased competition between tassel and ears, mitigating potential yield benefits of suppressing genetically pollen production.Este experimento foi conduzido em Ames, Iowa, US durante o ano agrícola de 1994, tendo como objetivo avaliar se a macho-esterelidade genético-citoplasmática pode ser utilizada para aumentar o rendimento de grãos de milho em diferentes populações de planta. Quatro genótipos foram utilizados: um híbrido (NK 6330 e uma linhagem, ambos em suas versões fértil e macho-estéril. Cada genótipo foi avaliado em duas densidades de semeadura, equivalentes a 25.000 e 75.000 pl.ha-1. Os híbridos produziram maiores rendimentos de grão do que as linhagens nas duas populações utilizadas. O rendimento de grãos por área foi maior em 75.000 do que em 25.000 pl.ha-1. Nenhuma diferença significativa em termos de rendimento de grãos, número de espigas por planta, número de grãos por espiga, comprimento e número de ramos do pendão, foi observada entre genótipos férteis e macho-estéreis, independentemente da

  20. Fertilization in echinoderms.

    Science.gov (United States)

    Santella, Luigia; Vasilev, Filip; Chun, Jong T

    2012-08-31

    For more than 150 years, echinoderm eggs have served as overly favored experimental model systems in which to study fertilization. Sea urchin and starfish belong to the same phylum and thus share many similarities in their fertilization patterns. However, several subtle but fundamental differences do exist in the fertilization of sea urchin and starfish, reflecting their phylogenetic bifurcation approximately 500 million years ago. In this article we review some of the seminal and recent findings that feature similarities and differences in sea urchin and starfish at fertilization. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. [Fertility preservation in oncology].

    Science.gov (United States)

    Chaput, Laure; Grémeau, Anne-Sophie; Vorilhon, Solène; Pons, Hanae; Chabrot, Cécile; Grèze, Victoria; Pouly, Jean-Luc; Brugnon, Florence

    2018-01-01

    Since the improvement of cancer diagnosis and treatment, survival rates of these patients increase. Gonadal damages are frequent consequences of cancer treatments with different evidence of impaired fertility. In this context, fertility preservation should be proposed to patients exposed to potentially gonadotoxic treatments. Different preservation approaches may be proposed depending on patient age, sex, cancer type and type of treatment. The indications of fertility preservation depend on sexual maturity. In young girls, ovarian cortex cryopreservation is the only technique feasible in order to preserve their reproductive potential. Vitrification of oocytes which needs ovarian stimulation or oocytes in vitro maturation is becoming more commonly performed for pubertal women to preserve their fertility. Ovarian cortex freezing could be offered to emergency fertility preservation of adult female cancer patients. In prepubertal boys, testicular tissue cryopreservation is the only line treatment for fertility preservation. For future use, various approaches are being evaluated such as spermatogonial stem cell injection or in vitro maturation. Cryopreservation of spermatozoa is, today, an established and successful technique for male adults. When there are no spermatozoa in ejaculate, sperm can be retrieved after treatment of testicular biopsy. The French bioethics law clearly indicates that fertility preservation should be proposed to patients exposed to potentially gonadotoxic treatment. Today, many approaches are possible. Fertility preservation indications are based on multidisciplinary consultations within platforms for the fertility preservation in order to optimize the patient care. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  2. Multislice computed tomography in an asymptomatic high-risk population.

    Science.gov (United States)

    Romeo, Francesco; Leo, Roberto; Clementi, Fabrizio; Razzini, Cinzia; Borzi, Mauro; Martuscelli, Eugenio; Pizzuto, Francesco; Chiricolo, Gaetano; Mehta, Jawahar L

    2007-02-01

    Approximately 50% of all acute coronary syndromes occur in previously asymptomatic patients. This study evaluated the value of multislice computed tomography for early detection of significant coronary artery disease (CAD) in high-risk asymptomatic subjects. One hundred sixty-eight asymptomatic subjects with >or=1 major risk factor (hypertension, diabetes, hypercholesterolemia, family history, or smoking) and an inconclusive or unfeasible noninvasive stress test result (stress electrocardiography, echocardiography, or nuclear scintigraphy) were evaluated in an outpatient setting. After clinical examination and laboratory risk analysis, all patients underwent multislice computed tomographic (MSCT) coronary angiography within 1 week. In all subjects, conventional coronary angiography was also carried out. Multislice computed tomography displayed single-vessel CAD in 16% of patients, 2-vessel CAD in 7%, and 3-vessel CAD in 4%. Selective coronary angiography confirmed the results of multislice computed tomography in 99% of all patients. Sensitivity and specificity of MSCT coronary angiography were 100% and 98%, respectively, with a positive predictive value of 95% and a negative predictive value of 100%. In conclusion, MSCT coronary angiography is an excellent noninvasive technique for early identification of significant CAD in high-risk asymptomatic patients with inconclusive or unfeasible noninvasive stress test results.

  3. Effects of culture media conditions on production of eggs fertilized in vitro of embryos derived from ovary of high grade Hanwoo.

    Science.gov (United States)

    Lee, Jun Young; Jung, Yun Gil; Seo, Byoung Boo

    2016-01-01

    This study was investigated the effects of culture media conditions on production of eggs fertilized in vitro of embryos from ovaries of high grade Korean native cow, Hanwoo. The IVMD 101 and IVF 100 were used for in vitro maturation of selected Hanwoo oocytes and In vitro embryo culture after in vitro fertilization, respectively. The IVMD 101 and IVD 101 were used for in vitro culture and completely free of serum. The cleavage rates of 2-cell embryos in reference to Hanwoo oocytes were 86.7, 92.9 , and 90.1 % in the control group, IVDM101 medium and IVD101 medium, respectively which indicates that the IVDM101 medium and IVD101 medium may result favorable outcomes. The in vitro development rates of blastocysts were 12.4, 38.4 and 32.4 % in the control group, serum free IVMD101 medium and IVD101 medium, respectively. For hatched blastocysts, it was 5.3, 33.9, and 28.6 % in the control group, serum free IVMD101 medium and IVD101 medium, respectively. Hence, more favorable results were expected for the hatched blastocysts in which the IVMD101 medium and IVD101 medium were used than the control group. Average cell numbers of blastocysts were 128.3, 165.7, and 163.6 in the groups of TCM-199 + 10 % FBS medium, IVMD 101 medium, and IVD 101 medium, respectively which clearly show that the IVMD 101 and IVD 101 medium consequence significantly higher cell numbers compared to the control group (i.e., TCM-199 + 10 % FBS medium). Pregnancy rate after embryo transfer was 39.6 % when the serum free medium was used which is higher than that of the medium supplemented with serum (32.8 %). In addition, stillbirth rates were 4.9 % in the group of serum free medium whereas it was 13.6 % in the serum supplemented medium (13.6 %). Taken altogether, serum free media, the IVMD 101 and IVD 101 represented more favorable results in the embryo development rate of embryos, cell numbers of blastocyst, and pregnancy rate. Of note, the IVMD 101 medium showed better outcomes

  4. Assisted oocyte activation following ICSI fertilization failure.

    Science.gov (United States)

    Vanden Meerschaut, Frauke; Nikiforaki, Dimitra; Heindryckx, Björn; De Sutter, Petra

    2014-05-01

    The capacity of intracytoplasmic sperm injection (ICSI) to permit almost any type of spermatozoa to fertilize oocytes has made it the most successful treatment for male factor infertility. Despite its high success rates, fertilization failure following ICSI still occurs in 1-3% of couples. Assisted oocyte activation (AOA) is being increasingly applied in human assisted reproduction to restore fertilization and pregnancy rates in couples with a history of ICSI fertilization failure. However, controversy still exists mainly because the artificial activating agents do not mimic precisely the initial physiological processes of mammalian oocyte activation, which has led to safety concerns. This review addresses the mechanism of human oocyte activation and the relatively rare phenomenon of fertilization failure after ICSI. Next, it describes the current diagnostic approaches and focuses on the application, efficiency and safety of AOA in human assisted reproduction. Copyright © 2014 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  5. High Levels of Bioplastic Are Produced in Fertile Transplastomic Tobacco Plants Engineered with a Synthetic Operon for the Production of Polyhydroxybutyrate1[C][OA

    Science.gov (United States)

    Bohmert-Tatarev, Karen; McAvoy, Susan; Daughtry, Sean; Peoples, Oliver P.; Snell, Kristi D.

    2011-01-01

    An optimized genetic construct for plastid transformation of tobacco (Nicotiana tabacum) for the production of the renewable, biodegradable plastic polyhydroxybutyrate (PHB) was designed using an operon extension strategy. Bacterial genes encoding the PHB pathway enzymes were selected for use in this construct based on their similarity to the codon usage and GC content of the tobacco plastome. Regulatory elements with limited homology to the host plastome yet known to yield high levels of plastidial recombinant protein production were used to enhance the expression of the transgenes. A partial transcriptional unit, containing genes of the PHB pathway and a selectable marker gene encoding spectinomycin resistance, was flanked at the 5′ end by the host plant’s psbA coding sequence and at the 3′ end by the host plant’s 3′ psbA untranslated region. This design allowed insertion of the transgenes into the plastome as an extension of the psbA operon, rendering the addition of a promoter to drive the expression of the transgenes unnecessary. Transformation of the optimized construct into tobacco and subsequent spectinomycin selection of transgenic plants yielded T0 plants that were capable of producing up to 18.8% dry weight PHB in samples of leaf tissue. These plants were fertile and produced viable seed. T1 plants producing up to 17.3% dry weight PHB in samples of leaf tissue and 8.8% dry weight PHB in the total biomass of the plant were also isolated. PMID:21325565

  6. High levels of bioplastic are produced in fertile transplastomic tobacco plants engineered with a synthetic operon for the production of polyhydroxybutyrate.

    Science.gov (United States)

    Bohmert-Tatarev, Karen; McAvoy, Susan; Daughtry, Sean; Peoples, Oliver P; Snell, Kristi D

    2011-04-01

    An optimized genetic construct for plastid transformation of tobacco (Nicotiana tabacum) for the production of the renewable, biodegradable plastic polyhydroxybutyrate (PHB) was designed using an operon extension strategy. Bacterial genes encoding the PHB pathway enzymes were selected for use in this construct based on their similarity to the codon usage and GC content of the tobacco plastome. Regulatory elements with limited homology to the host plastome yet known to yield high levels of plastidial recombinant protein production were used to enhance the expression of the transgenes. A partial transcriptional unit, containing genes of the PHB pathway and a selectable marker gene encoding spectinomycin resistance, was flanked at the 5' end by the host plant's psbA coding sequence and at the 3' end by the host plant's 3' psbA untranslated region. This design allowed insertion of the transgenes into the plastome as an extension of the psbA operon, rendering the addition of a promoter to drive the expression of the transgenes unnecessary. Transformation of the optimized construct into tobacco and subsequent spectinomycin selection of transgenic plants yielded T0 plants that were capable of producing up to 18.8% dry weight PHB in samples of leaf tissue. These plants were fertile and produced viable seed. T1 plants producing up to 17.3% dry weight PHB in samples of leaf tissue and 8.8% dry weight PHB in the total biomass of the plant were also isolated.

  7. Teenage cervical screening in a high risk American population

    Directory of Open Access Journals (Sweden)

    Songlin Zhang

    2011-01-01

    Full Text Available Background: The new 2009 ACOG guideline for cervical cytology screening changed the starting age to 21 years regardless of the age of onset of sexual intercourse. However, many recent studies have shown a dramatic increase in the incidence of cervical epithelial abnormalities among adolescents within the past two decades. Materials and Methods: For this study, the reports of 156,342 cervical cytology were available of which 12,226 (7.8% were from teenagers. A total of 192 teenagers with high grade intraepithelial lesion (HSIL cervical cytology were identified. The ages ranged from 13 to 19 years with a mean of 17.7 years and a median of 18 years. Among them, 31.3% were pregnant, 12.0% were postpartum, and 13.5% were on oral contraceptive. Ninety-eight had prior cervical cytology. Results: The teenagers had statistically significant higher detection rates of overall abnormal cervical cytology (23.6% vs. 6.6%, P = 0, with 15.4% vs. 3.2% (P = 0 of low grade intraepithelial lesion (LSIL and 1.8% vs. 1.0% (P = 2.56 Χ 10 -13 of HSIL compared to women ≥20 years. The teenage group had the highest abnormal cytology among all age groups. The LSIL/HSIL ratio was 8.5:1 for teenagers and 3.1:1 for women ≥20 years. A total of 131 teenagers had cervical biopsies within 12 months of the HSIL cytology, with diagnoses of 39 CIN 3, 1 VAIN 3, 15 CIN 2, 62 CIN 1, and 14 had a negative histology (CIN 0. Only in 19 of these 39 women, the CIN 2/3 lesion proved to be persistent. Conclusion: We conclude that cytology screening of high risk teenagers is effective in detecting CIN 2/3 lesions. Moreover, treatment and careful follow-up can be realized.

  8. Fertility preservation in young cancer patients

    Directory of Open Access Journals (Sweden)

    Ariel Revel

    2010-01-01

    Full Text Available As a result of advances in treatment, almost 80% of children and adolescents who receive a diagnosis of cancer become long-term survivors. The increased survival rate of children and adolescents with cancer has resulted in a major interest in the long-term effects of cancer treatment on the possibility for future fertility. Currently established methods for the preservation of fertility are available only for pubertal males and females. Pubertal male cancer patients should be encouraged to freeze numerous sperm samples even when sperm count and motility are poor. In these cases, intracytoplasmic sperm injection is a powerful technique compared with intrauterine insemination since thawed sperm samples with poor parameters can produce relatively high fertilization rates resulting in normal pregnancies and deliveries. Married pubertal women should be proposed ovulation induction, follicular aspiration, and fertilization with husband sperm. Single women could benefit from vitrification of oocytes. This requires a delay of about 3 weeks in the commencement of chemotherapy to enable follicular growth. Fertility preservation for prepubertal patients is more of a problem. Young girls could be offered cryopreservation of gametes in the gonadal tissue. Cryopreservation of testicular tissue was suggested for fertility preservation for young boys, but this method is totally experimental and not currently offered. Discussing future fertility is part of the consultation of young female and male patients facing potentially gonadotoxic cancer therapy. It is the role of reproductive specialists to create various options in their laboratory to preserve fertility potential of cancer patients.

  9. Religiosity, nationalism and fertility in Israel.

    Science.gov (United States)

    Anson, J; Meir, A

    1996-03-01

    It is suggested that Israel's high fertility can be explained by a collective national conscience rather than the traditional interpretation of Jewish religiosity. It is suggested that religiosity is a proxy for a national consciousness and daily living standards. It is argued that normative orientations or cultural explanations of the value of children are intervening variables according to the framework established by Davis and Blake. The collective conscience reflects Israel's special position in the Middle East and within the world economy. The nationalist feelings reflect a range in political views. The author disputes the ethnic and religious explanations for high fertility. Fertility increased since the 1960s even among low fertility European-American born women. During the early 1980s fertility was 2.75, which was high compared to European levels at the same standard of living. Reference is made to the literature on the association between high fertility and survival strategies in insecure or discriminatory settings. This study's analysis is based on a macro- rather than individual-level approach to understanding behavior. The theoretical framework is based on the theories of Durkheim and Gane. The analysis uses data from the 1983 census on Jewish fertility in urban statistical areas and Jewish voting patterns in national elections in 1984. Correspondence analysis is used to identify voting patterns by area. The four political postures are identified as religious and conciliatory (71 areas), religious and nationalist (142 areas), nonreligious and nationalist, and nonreligious and conciliatory. Women in nationalist areas had 35% more children than women in conciliatory areas. Although both religiosity and nationalism were positively correlated with high fertility, nationalist commitment was a better predictor. The model including religiosity, nationalism, and income showed no independent effect of religiosity on fertility.

  10. Fertilizer Use and Water Quality.

    Science.gov (United States)

    Reneau, Fred; And Others

    This booklet presents informative materials on fertilizer use and water quality, specifically in regard to environmental pollution and protection in Illinois. The five chapters cover these topics: Fertilizer and Water Quality, Fertilizer Use, Fertilizers and the Environment, Safety Practices, and Fertilizer Management Practices. Key questions are…

  11. High-Resolution Maps of Mouse Reference Populations

    Directory of Open Access Journals (Sweden)

    Petr Simecek

    2017-10-01

    Full Text Available Genetic reference panels are widely used to map complex, quantitative traits in model organisms. We have generated new high-resolution genetic maps of 259 mouse inbred strains from recombinant inbred strain panels (C57BL/6J × DBA/2J, ILS/IbgTejJ × ISS/IbgTejJ, and C57BL/6J × A/J and chromosome substitution strain panels (C57BL/6J-Chr#, C57BL/6J-Chr#, and C57BL/6J-Chr#. We genotyped all samples using the Affymetrix Mouse Diversity Array with an average intermarker spacing of 4.3 kb. The new genetic maps provide increased precision in the localization of recombination breakpoints compared to the previous maps. Although the strains were presumed to be fully inbred, we found residual heterozygosity in 40% of individual mice from five of the six panels. We also identified de novo deletions and duplications, in homozygous or heterozygous state, ranging in size from 21 kb to 8.4 Mb. Almost two-thirds (46 out of 76 of these deletions overlap exons of protein coding genes and may have phenotypic consequences. Twenty-nine putative gene conversions were identified in the chromosome substitution strains. We find that gene conversions are more likely to occur in regions where the homologous chromosomes are more similar. The raw genotyping data and genetic maps of these strain panels are available at http://churchill-lab.jax.org/website/MDA.

  12. Multiple Pregnancy and Birth: Considering Fertility Treatments

    Science.gov (United States)

    ... highly qualified experts. In addition to residencies in obstetrics and gynecology, fertility experts (i.e., reproductive endocrinologists) have additional training in reproductive medicine and infertility. To obtain the best outcomes for you and your family, the decision to ...

  13. Children Procedures and Treatment (Fertility Issues)

    Medline Plus

    Full Text Available ... for prepubertal boys? Is ovarian suppression an appropriate fertility preservation option for girls under 18? Why is bone marrow transplantation associated with a high risk of infertility? What is dose fractionation? What is the difference ...

  14. Improved fertility following conservative surgical treatment of ectopic pregnancy

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Lund, Claus Otto; Ottesen, Bent

    2003-01-01

    pathology, the chance of pregnancy was poor (hazard ratio 0.463) and the risk of recurrence was high (hazard ratio 2.25), assessed with Cox regression. The rate of persistent ectopic pregnancy was 8%. CONCLUSION: Conservative surgery is superior to radical surgery at preserving fertility. Conservative...... surgery is not followed by an increased risk of repeat ectopic pregnancy, but by the risk of persistent ectopic pregnancy, which should be taken into account when deciding on the operative procedure. Management in case of contralateral tubal pathology is disputed and should ideally be addressed......OBJECTIVE: To evaluate fertility after salpingectomy or tubotomy for ectopic pregnancy. DESIGN: Retrospective cohort study. SETTING: Clinical University Center, Hvidovre Hospital, Copenhagen. POPULATION: Two hundred and seventy-six women undergoing salpingectomy or tubotomy for their first ectopic...

  15. In vitro induction of the acrosome reaction in bull sperm and the relationship to field fertility using low-dose inseminations

    DEFF Research Database (Denmark)

    Birck, A; Christensen, P; Labouriau, R

    2010-01-01

    The acrosome reaction (AR) is a prerequisite for normal sperm fertilizing capability and can be studied in vitro after induction by various agents. The efficacy of a sperm population to undergo the AR in vivo is expected to influence male fertilizing potential. During the past two decades, a number...... of attempts have been made to relate the in vitro-induced AR to field fertility in several species. However, to our knowledge, no studies have combined in vitro induction of the AR with the simultaneous detection of sperm viability and acrosomal status using a high-precision flow cytometric technique....... Furthermore, large-scale fertility trials using low-dose inseminations are pending. In the current study, the relationship between field fertility and the in vitro-induced AR was investigated using three ejaculates from each of 195 bulls, 156 Holstein and 39 Jersey bulls (Bos taurus), participating...

  16. Assessing the in situ fertilization status of two marine copepod species, Temora longicornis and Eurytemora herdmani; how common are unfertilized eggs in nature?

    Directory of Open Access Journals (Sweden)

    Rachel S Lasley-Rasher

    Full Text Available We utilized an egg staining technique to measure the in situ fertilization success of two marine copepod species, Temora longicornis and Eurytemora herdmani from May to October 2008 in coastal Maine and correlated fertilization success with environmental conditions in their habitat. T. longicornis is a free spawning species that releases eggs into the ambient seawater after mating. In contrast, E. herdmani carries eggs in an egg sac until they hatch. The proportion of fertilized eggs within E. herdmani egg sacs was significantly higher than the freely spawned clutches of T. longicornis. This may be a result of the asymmetrical costs associated with carrying vs. spawning unfertilized eggs. T. longicornis frequently laid both fertilized and unfertilized eggs within their clutch. T. longicornis fertilization was negatively associated with chlorophyll concentration and positively associated with population density in their local habitat. The fertilization status of E. herdmani egg sacs was high throughout the season, but the proportion of ovigerous females was negatively associated with an interaction between predators and the proportion of females in the population. This study emphasizes that, in addition to population level processes, community and ecosystem level processes strongly influence the fertilization success and subsequent productivity of copepods.

  17. Fertilizers and soil improvers

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    In greenhouse industry fertilizers as well as soil improvers are widely used. Fertilizers are mainly applied to optimize the physical-chemical conditions of the root environment and are used for growing in soils in situ as well as for growing in substrates. Soil improvers are materials solely added

  18. Economic development and fertility.

    Science.gov (United States)

    Heer, D M

    1966-06-01

    Two schools of theorists have been concerned with the effect of economic development on fertility. One school has contended that economic development has an inhibiting effect on fertility. The demographic transition which has occurred among the non-developed countries confirms their viewpoint. Another school of thought, including in its members Thomas Malthus, has believed that economic development promoted fertility. Much empirical evidence may also be brought to bear to support this viewpoint.The present paper attempts to reconcile these viewpoints. It is hypothesized that the direct effect of economic development is to increase fertility. However, various factors which usually accompany the process of economic development serve to reduce fertility. These include an increase in the level of education and a reduction in infant and childhood mortality. Making use of data for 41 nations pertaining to the decade of the 1950's, it is found that fertility is directly associated with per capita net national product when controls for other relevant variables are in8tituted. On the other hand, per capita newspaper circulation is inversely related to fertility, and infant mortality is directly related.If the hypothesis advanced in this paper is correct, relatively large governmental expenditures on health and education will enhance the reduction in fertility obtainable from an increase in national economic level alone.

  19. Fertilization in Flowering Plants

    Indian Academy of Sciences (India)

    IAS Admin

    In reality all pre-fertilization events involved in screening and selection of the partners, so ... In reality, flowering plants also perform all essential pre-fertilization events to screen and ..... adequate in the habitat. It increases pollination efficiency since the pollinator and the plant species have evolved to optimize pollen transfer.

  20. THE INFLUENCE OF RED WORMS (E. FOETIDA ON COMPOST’S FERTILIZING PROPERTIES

    Directory of Open Access Journals (Sweden)

    Czesława Rosik-Dulewska

    2014-04-01

    Full Text Available Composting is becoming a more and more common way of biodegradable waste disposal. Composts should be characterized by high content of nutrients and low amount of pollutants. Vermicompost is a compost produced by overpopulated culture of earthworm Eisenia foetida (Savigny 1826. World scientific literature states that vermicompost has a high fertilizing value which often exceeds such value of conventional composts. The results showed that vermicompost has a much higher fertilizing value than the compost produced by the traditional pile method. However, prism vermicompost created with the participation of a less concentrated population of earthworms has an intermediate value as a fertilizer (nitrogen and heavy metals, it could be assessed as a lower value product due to the lower content of potassium and phosphorus than the material obtained without earthworms.

  1. A High Dietary Glycemic Index Increases Total Mortality in a Mediterranean Population at High Cardiovascular Risk

    Science.gov (United States)

    Castro-Quezada, Itandehui; Sánchez-Villegas, Almudena; Estruch, Ramón; Salas-Salvadó, Jordi; Corella, Dolores; Schröder, Helmut; Álvarez-Pérez, Jacqueline; Ruiz-López, María Dolores; Artacho, Reyes; Ros, Emilio; Bulló, Mónica; Covas, María-Isabel; Ruiz-Gutiérrez, Valentina; Ruiz-Canela, Miguel; Buil-Cosiales, Pilar; Gómez-Gracia, Enrique; Lapetra, José; Pintó, Xavier; Arós, Fernando; Fiol, Miquel; Lamuela-Raventós, Rosa María; Martínez-González, Miguel Ángel; Serra-Majem, Lluís

    2014-01-01

    Objective Different types of carbohydrates have diverse glycemic response, thus glycemic index (GI) and glycemic load (GL) are used to assess this variation. The impact of dietary GI and GL in all-cause mortality is unknown. The objective of this study was to estimate the association between dietary GI and GL and risk of all-cause mortality in the PREDIMED study. Material and Methods The PREDIMED study is a randomized nutritional intervention trial for primary cardiovascular prevention based on community-dwelling men and women at high risk of cardiovascular disease. Dietary information was collected at baseline and yearly using a validated 137-item food frequency questionnaire (FFQ). We assigned GI values of each item by a 5-step methodology, using the International Tables of GI and GL Values. Deaths were ascertained through contact with families and general practitioners, review of medical records and consultation of the National Death Index. Cox regression models were used to estimate multivariable-adjusted hazard ratios (HR) and their 95% CI for mortality, according to quartiles of energy-adjusted dietary GI/GL. To assess repeated measures of exposure, we updated GI and GL intakes from the yearly FFQs and used Cox models with time-dependent exposures. Results We followed 3,583 non-diabetic subjects (4.7 years of follow-up, 123 deaths). As compared to participants in the lowest quartile of baseline dietary GI, those in the highest quartile showed an increased risk of all-cause mortality [HR = 2.15 (95% CI: 1.15–4.04); P for trend  = 0.012]. In the repeated-measures analyses using as exposure the yearly updated information on GI, we observed a similar association. Dietary GL was associated with all-cause mortality only when subjects were younger than 75 years. Conclusions High dietary GI was positively associated with all-cause mortality in elderly population at high cardiovascular risk. PMID:25250626

  2. Mitochondrial DNA Analyses Indicate High Diversity, Expansive Population Growth and High Genetic Connectivity of Vent Copepods (Dirivultidae) across Different Oceans.

    Science.gov (United States)

    Gollner, Sabine; Stuckas, Heiko; Kihara, Terue C; Laurent, Stefan; Kodami, Sahar; Martinez Arbizu, Pedro

    2016-01-01

    Communities in spatially fragmented deep-sea hydrothermal vents rich in polymetallic sulfides could soon face major disturbance events due to deep-sea mineral mining, such that unraveling patterns of gene flow between hydrothermal vent populations will be an important step in the development of conservation policies. Indeed, the time required by deep-sea populations to recover following habitat perturbations depends both on the direction of gene flow and the number of migrants available for re-colonization after disturbance. In this study we compare nine dirivultid copepod species across various geological settings. We analyze partial nucleotide sequences of the mtCOI gene and use divergence estimates (FST) and haplotype networks to infer intraspecific population connectivity between vent sites. Furthermore, we evaluate contrasting scenarios of demographic population expansion/decline versus constant population size (using, for example, Tajima's D). Our results indicate high diversity, population expansion and high connectivity of all copepod populations in all oceans. For example, haplotype diversity values range from 0.89 to 1 and FST values range from 0.001 to 0.11 for Stygiopontius species from the Central Indian Ridge, Mid Atlantic Ridge, East Pacific Rise, and Eastern Lau Spreading Center. We suggest that great abundance and high site occupancy by these species favor high genetic diversity. Two scenarios both showed similarly high connectivity: fast spreading centers with little distance between vent fields and slow spreading centers with greater distance between fields. This unexpected result may be due to some distinct frequency of natural disturbance events, or to aspects of individual life histories that affect realized rates of dispersal. However, our statistical performance analyses showed that at least 100 genomic regions should be sequenced to ensure accurate estimates of migration rate. Our demography parameters demonstrate that dirivultid

  3. Population, environment and sustainable development.

    Science.gov (United States)

    Abeykoon, A T

    1993-01-01

    The present population of Sri Lanka (17.7 million) is sufficient to create concern about the use, limitations, and waste of natural resources. Between 1871 and 1946, the population grew at an average rate of 1.4% annually, with high fertility and mortality. The population doubled between 1946 and 1981, and mortality declined. Between 1971 and 1991, the rate of growth declined due to a decrease in fertility and an increase in emigration. With a growth rate of 1.4%, the population will again double to 35 million by 2040. Technological improvements in Sri Lanka have led to an eight-fold increase in metric tons of rice production, but the growth in population has caused a deficiency in output so that basic per capita caloric requirements are not being met. Increased productivity has almost depleted the area available for cultivation, and the use of fertilizers to increase yields has environmental drawbacks. The high fertility of the 1970s contributed to increased labor force participation rates of 2.2%, which resulted in more people joining the labor force than leaving. Thus, the employment market has been unable to absorb the unemployed or potential new workers. Growth of the employment market may also conflict with environmental protection, as exemplified by the mining of the coral reef on the southwestern coast. The conversion of forests to agriculture resulted in forest losses of about 42,000 hectares per year during 1956-83. Deforestation is also occurring in the high forests due to increased pressure for fuelwood. In the wet zone, the use of forests for fuelwood is declining, but rubber wood is being harvested for industrial production. In order to slow population growth to replacement levels by the year 2000 (with a total population of 25 million), contraceptive prevalence must be increased to 72% at a cost of about $25 million.

  4. A 660-Kb Deletion with Antagonistic Effects on Fertility and Milk Production Segregates at High Frequency in Nordic Red Cattle: Additional Evidence for the Common Occurrence of Balancing Selection in Livestock

    Science.gov (United States)

    Kadri, Naveen Kumar; Sahana, Goutam; Charlier, Carole; Iso-Touru, Terhi; Guldbrandtsen, Bernt; Karim, Latifa; Nielsen, Ulrik Sander; Panitz, Frank; Aamand, Gert Pedersen; Schulman, Nina; Georges, Michel; Vilkki, Johanna; Lund, Mogens Sandø; Druet, Tom

    2014-01-01

    In dairy cattle, the widespread use of artificial insemination has resulted in increased selection intensity, which has led to spectacular increase in productivity. However, cow fertility has concomitantly severely declined. It is generally assumed that this reduction is primarily due to the negative energy balance of high-producing cows at the peak of lactation. We herein describe the fine-mapping of a major fertility QTL in Nordic Red cattle, and identify a 660-kb deletion encompassing four genes as the causative variant. We show that the deletion is a recessive embryonically lethal mutation. This probably results from the loss of RNASEH2B, which is known to cause embryonic death in mice. Despite its dramatic effect on fertility, 13%, 23% and 32% of the animals carry the deletion in Danish, Swedish and Finnish Red Cattle, respectively. To explain this, we searched for favorable effects on other traits and found that the deletion has strong positive effects on milk yield. This study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle, and that associated positive effects on milk yield may account for part of the negative genetic correlation. Our study adds to the evidence that structural variants contribute to animal phenotypic variation, and that balancing selection might be more common in livestock species than previously appreciated. PMID:24391517

  5. A 660-Kb deletion with antagonistic effects on fertility and milk production segregates at high frequency in Nordic Red cattle: additional evidence for the common occurrence of balancing selection in livestock.

    Directory of Open Access Journals (Sweden)

    Naveen Kumar Kadri

    2014-01-01

    Full Text Available In dairy cattle, the widespread use of artificial insemination has resulted in increased selection intensity, which has led to spectacular increase in productivity. However, cow fertility has concomitantly severely declined. It is generally assumed that this reduction is primarily due to the negative energy balance of high-producing cows at the peak of lactation. We herein describe the fine-mapping of a major fertility QTL in Nordic Red cattle, and identify a 660-kb deletion encompassing four genes as the causative variant. We show that the deletion is a recessive embryonically lethal mutation. This probably results from the loss of RNASEH2B, which is known to cause embryonic death in mice. Despite its dramatic effect on fertility, 13%, 23% and 32% of the animals carry the deletion in Danish, Swedish and Finnish Red Cattle, respectively. To explain this, we searched for favorable effects on other traits and found that the deletion has strong positive effects on milk yield. This study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle, and that associated positive effects on milk yield may account for part of the negative genetic correlation. Our study adds to the evidence that structural variants contribute to animal phenotypic variation, and that balancing selection might be more common in livestock species than previously appreciated.

  6. Projected near-future levels of temperature and pCO2 reduce coral fertilization success.

    Directory of Open Access Journals (Sweden)

    Rebecca Albright

    Full Text Available Increases in atmospheric carbon dioxide (pCO2 are projected to contribute to a 1.1-6.4°C rise in global average surface temperatures and a 0.14-0.35 reduction in the average pH of the global surface ocean by 2100. If realized, these changes are expected to have negative consequences for reef-building corals including increased frequency and severity of coral bleaching and reduced rates of calcification and reef accretion. Much less is known regarding the independent and combined effects of temperature and pCO2 on critical early life history processes such as fertilization. Here we show that increases in temperature (+3°C and pCO2 (+400 µatm projected for this century negatively impact fertilization success of a common Indo-Pacific coral species, Acropora tenuis. While maximum fertilization did not differ among treatments, the sperm concentration required to obtain 50% of maximum fertilization increased 6- to 8- fold with the addition of a single factor (temperature or CO2 and nearly 50- fold when both factors interact. Our results indicate that near-future changes in temperature and pCO2 narrow the range of sperm concentrations that are capable of yielding high fertilization success in A. tenuis. Increased sperm limitation, in conjunction with adult population decline, may have severe consequences for coral reproductive success. Impaired sexual reproduction will further challenge corals by inhibiting population recovery and adaptation potential.

  7. Effects of racing on equine fertility.

    Science.gov (United States)

    Sairanen, J; Katila, T; Virtala, A-M; Ojala, M

    2011-03-01

    Racing and fertility are connected with each other in many ways. Stress and increased body temperature induced by racing may have negative effects on fertility, but on the other hand, high quality nutrition and management of racing horses may have positive effects. Fertility may also be genetically associated with racing performance. The analysed data consisted of Finnish mating records of Standardbreds (n=33,679) and Finnhorses (n=32,731), from 1991 to 2005, and the harness racing records of both mares and stallions. Fertility was measured by foaling outcome, and racing performance was measured by best time and number of races. We used racing results from the mating year and from the entire career, to study both short-term and long-term effects of racing on fertility. The analyses were conducted with a linear mixed model, where racing was fitted as a fixed factor. In a separate bivariate analysis we measured the genetic correlation of racing and fertility, applying a threshold model for the fertility trait. For mares, racing after the first mating or more than 10 times during the mating year diminished the foaling outcome. However, racing only before the first mating or 1-5 times during the mating year had positive effects on mare fertility. Stallion fertility did not suffer from racing during the mating year. The mares with the best career racing records had the highest foaling rates, but this was probably due to preferential treatment. The genetic correlation between best racing record and fertility was favourable but weak in the Finnhorse (-0.24±0.08), and negligible in the Standardbred (-0.15±0.11). Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Risk of cardiovascular disease in a traditional African population with a high infectious load: a population-based study.

    Directory of Open Access Journals (Sweden)

    Jacob J E Koopman

    Full Text Available BACKGROUND: To test the inflammatory origin of cardiovascular disease, as opposed to its origin in western lifestyle. Population-based assessment of the prevalences of cardiovascular risk factors and cardiovascular disease in an inflammation-prone African population, including electrocardiography and ankle-arm index measurement. Comparison with known prevalences in American and European societies. METHODOLOGY/PRINCIPAL FINDINGS: Traditional population in rural Ghana, characterised by adverse environmental conditions and a high infectious load. Population-based sample of 924 individuals aged 50 years and older. Median values for cardiovascular risk factors, including waist circumference, BMI, blood pressure, and markers of glucose and lipid metabolism and inflammation. Prevalence of myocardial infarction detected by electrocardiography and prevalence of peripheral arterial disease detected by ankle-arm index. When compared to western societies, we found the Ghanaians to have more proinflammatory profiles and less cardiovascular risk factors, including obesity, dysglycaemia, dyslipidaemia, and hypertension. Prevalences of cardiovascular disease were also lower. Definite myocardial infarction was present in 1.2% (95%CI: 0.6 to 2.4%. Peripheral arterial disease was present in 2.8% (95%CI: 1.9 to 4.1%. CONCLUSIONS/SIGNIFICANCE: Taken together, our data indicate that for the pathogenesis of cardiovascular disease inflammatory processes alone do not suffice and additional factors, probably lifestyle-related, are mandatory.

  9. Fertility rates: the decline is stalling.

    Science.gov (United States)

    Starke, L

    1994-01-01

    During the 1970s, the rate of total fertility in China fell from 6.4 children per woman in 1968 to 2.2 in 1980. The decline in India was more modest, but still significant at 5.8 over the period 1966-71 to 4.8 during 1976-1981. These trends helped slow the rate of world population growth from 2.1% during 1965-70 to 1.7% during 1975-80. Fertility rates are currently declining in similar fashion in Brazil, Egypt, Indonesia, Mexico, and Thailand. While impressive and much needed to ultimately stabilize world population growth, fertility declines in China and India stalled throughout the 1980s. The fertility rate in China remained around 2.5 throughout much of the decade, while progress toward lower birth rates stalled in India after the defeat of the ruling Congress Party in the late 1970s. Moreover, 67 developing countries, home to 17% of global population, have yet to enter the phase of demographic transition. It is clear that governments must supply contraceptives and reproductive health care services to couples in need of regulating their fertility, but they must also lower the demand for children by working to improve women's lives and increase their access to and control over money, credit, and other resources.

  10. Evaluation of Nano Structured Slow Release Fertilizer on the Soil Fertility, Yield and Nutritional Profile of Vigna radiata.

    Science.gov (United States)

    Mala, Rajendran; Selvaraj, Ruby Celsia Arul; Sundaram, Vidhya Barathi; Rajan, Raja Blessina Siva Shanmuga; Gurusamy, Uma Maheswari

    2017-01-01

    The excessive use of fertilizers and pesticides has distorted soil composition, fertility and integrity with non-desirable environmental and ecological consequences. A strategy was designed to prepare a nano structured slow release fertilizer system that delivers nutrients and plant growth promoting rhizobacteria simultaneously. Slow release nano phosphate and potash fertilizer was prepared by blending the nano emulsion of fertilizer with neem cake and PGPR. Slow release nano phosphate and potash fertilizer was prepared by blending the nano emulsion of fertilizer with neem cake and PGPR. Few patents relevant to the topic have been reviewed and cited. The influence of nano structured slow release fertilizer on the biochemical characteristics, soil and yield attributes of Vigna radiata was studied in the field by randomized block design. The treatments used to evaluate the effect of nano SRF were a control (without any fertilizer), neem cake, chemical fertilizer, PGPR and nano SRF. Germination, specific activity of enzymes, carbohydrates, protein, photosynthetic pigments, root nodule number and microbial population were assessed by standard methods. The size of the nano urea slow release fertilizer ranged from 52.41 nm to 69.86 nm, and the size of the phosphate and potash fertilizer ranged from 81.85 nm to 87 nm. The weights of 1000 grains were 31.8 g, 33.28 g, 33.39 g, 36.65 g and 44.90 g in the control, neem cake, chemical fertilizer, PGPR and nano SRF, respectively. The protein concentrations were 162 mg g-1 in the control, 231 mg g-1 in the neem cake, 192 mg g-1 in the chemical fertilizer, 285 mg g-1 in the PGPR and 336 mg g-1 in the nano SRF. Nano slow release fertilizer treatment has stimulated germination and biochemical characteristics in Vigna radiata that are positively reflected in the yield attributes. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  11. Cartography of Emergency Department Visits for Asthma – Targeting High-Morbidity Populations

    Directory of Open Access Journals (Sweden)

    Pierre Lajoie

    2004-01-01

    Full Text Available BACKGROUND: Asthma education should be offered with priority to populations with the highest asthma-related morbidity. In the present study, the aim was to identify populations with high-morbidity for asthma from the Quebec Health Insurance Board Registry, a large administrative database, to help the Quebec Asthma and Chronic Obstructive Pulmonary Disease Network target its interventions.

  12. Population geography.

    Science.gov (United States)

    Nash, A

    1994-03-01

    Population geographers are involved in contemporary policy issues, the production of quality work, and successful communication of research findings. This article reviewed some contributions population geographers have made to the understanding of the geographic impact of aging and the consequences of migration. Geographers have come late to the study of aging and have focused primarily on four main policy issues: 1) fertility decline, 2) housing demography, 3) aged patterns of housing and migration, and 4) government policy. Fertility decline research has highlighted information diffusion theories for fertility decline by researchers such as Zelinsky, Skeldon, and Noin. Changes in attitudes and the removal on constraints has been examined by Woods. Residential mobility studies have been the focus of researchers such as Gober, Moore, and Clark, and Myers. Regional labor markets and the movement of the "baby boom" through the life course have been examined by Miron, Plane and Rogerson, and Clout, who studied the empty nesters and the movement out of suburbia. Private residential housing has increased for the elderly in England and Wales (Hamnett and Mullings), and seasonal migration of Minnesotans results in lost sales revenues and high health and social costs for those too ill to travel (Craig). Geographers have not accomplished a significant thrust into the literature on demographic aging. Contributions to the transnational and international literature have resulted in internal migration studies by Clout on "counterurbanization" in northwestern industrial Europe, while Fielding, Baltensperger, Marchand and Scott, and Jones have examined the continuing rural-urban migration. The loss of urban population has been associated with inner city problems, the impact of labor supply and market demand, and the revenue and health care consequences in the work of Champion, Gibson, and Champion and Illeris, and Craig. Impacts are felt differently by geographic location, and

  13. Unexpected high genetic diversity in small populations suggests maintenance by associative overdominance.

    Science.gov (United States)

    Schou, Mads F; Loeschcke, Volker; Bechsgaard, Jesper; Schlötterer, Christian; Kristensen, Torsten N

    2017-12-01

    The effective population size (Ne ) is a central factor in determining maintenance of genetic variation. The neutral theory predicts that loss of variation depends on Ne , with less genetic drift in larger populations. We monitored genetic drift in 42 Drosophila melanogaster populations of different adult census population sizes (10, 50 or 500) using pooled RAD sequencing. In small populations, variation was lost at a substantially lower rate than expected. This observation was consistent across two ecological relevant thermal regimes, one stable and one with a stressful increase in temperature across generations. Estimated ratios between Ne and adult census size were consistently higher in small than in larger populations. The finding provides evidence for a slower than expected loss of genetic diversity and consequently a higher than expected long-term evolutionary potential in small fragmented populations. More genetic diversity was retained in areas of low recombination, suggesting that associative overdominance, driven by disfavoured homozygosity of recessive deleterious alleles, is responsible for the maintenance of genetic diversity in smaller populations. Consistent with this hypothesis, the X-chromosome, which is largely free of recessive deleterious alleles due to hemizygosity in males, fits neutral expectations even in small populations. Our experiments provide experimental answers to a range of unexpected patterns in natural populations, ranging from variable diversity on X-chromosomes and autosomes to surprisingly high levels of nucleotide diversity in small populations. © 2017 John Wiley & Sons Ltd.

  14. Dynamic Responses in a Plant-Insect System to Fertilization by Cormorant Feces

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    Gundula Kolb

    2015-04-01

    Full Text Available Theoretical arguments suggest that increased plant productivity may not only increase consumer densities but also their fluctuations. While increased consumer densities are commonly observed in fertilization experiments, experiments are seldom performed at a spatial and temporal scale where effects on population fluctuations may be observed. In this study we used a natural gradient in soil fertility caused by cormorant nesting. Cormorants feed on fish but defecate on their nesting islands. On these islands we studied soil nutrient availability, plant nutrient content and the density of Galerucella beetles, main herbivores feeding on Lythrum salicaria. In a common garden experiment, we followed larval development on fertilized plants and estimated larval stoichiometry. Soil nutrient availability varied among islands, and several cormorant islands had very high N and P soil content. Plant nutrient content, however, did not vary among islands, and there was no correlation between soil and plant nutrient contents. Beetle densities increased with plant nutrient content in the field study. However, there was either no effect on temporal fluctuations in beetle density or that temporal fluctuations decreased (at high P. In the common garden experiment, we found limited responses in either larval survival or pupal weights to fertilization. A possible mechanism for the limited effect of fertilization on density fluctuations may be that the distribution of L. salicaria on nesting islands was restricted to sites with a lower N and P content, presumably because high N loads are toxic.

  15. Late onset variants in Fabry disease: Results in high risk population screenings in Argentina

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    G. Serebrinsky

    2015-09-01

    Conclusions: Screening programs for FD in high risk populations are important as FD is a treatable multisystemic disease which is frequently overlooked in patients who present without classical manifestations.

  16. [Quadratic Orthogonal Rotation Combination Design on Alisma orientalis of Fertilization].

    Science.gov (United States)

    Li, Yao; Chen, Xing-fu; Peng, Shi-ming; Liang, Qin; Zhang, Jun; Wu, Chun

    2015-04-01

    To study the effects of combined N, P, K and micronutrient fertilizers on the yield of Alisma orientalis tuber, and to optimize the fertilizer application rate. Four factors five levels quadratic orthogonal rotation combination design was used. A function was established on nitrogen, phosphor, potassium and microelement fertilizer application rate with the yield of Alisma orientalis tuber. The established mathematical model was of high reliability for prediction with quadratic regression equation of R2 = 0. 8980. The order of increasing Alisma orientalis tuber yield was nitrogen > micronutrient fertilizer > potassium > phosphor. The results of the frequency analysis showed that for the target yield over 8 250 kg/hm2 and the confidence interval of 95%, the optimal fertilizer application rates were as follows :nitrogen of 241. 45 - 283. 55 kg/hm2, phosphor of 81. 14 - 208. 44 kg/hm2, potassium of 95. 57 - 239. 42 kg/hm2, and zinc fertilizer of 14. 32 - 16. 18 kg/hm2, boron fertilizer of 18. 84 - 19. 86 kg/hm2, and molybdenum fertilizer of 0. 151 -0. 159 kg/hm2 in micronutrient fertilizer. Nitrogen is related to the growth of Alisma orientalis, potassium promotes tuber bulking, micronutrient fertilizer consisted of zinc, boron and molybdenum fertilizer promotes Alisma orientalis growth and the absorption of nitrogen, phosphor and potassium. Moderate application of nitrogen, phosphorus, potassium, zinc, boron and molybdenum fertilizer can promote Alisma orientalis tuber yield. The nitrogen has the best effect.

  17. The Middle East population puzzle.

    Science.gov (United States)

    Omran, A R; Roudi, F

    1993-07-01

    An overview is provided of Middle Eastern countries on the following topics; population change, epidemiological transition theory and 4 patterns of transition in the middle East, transition in causes of death, infant mortality declines, war mortality, fertility, family planning, age and sex composition, ethnicity, educational status, urbanization, labor force, international labor migration, refugees, Jewish immigration, families, marriage patterns, and future growth. The Middle East is geographically defined as Bahrain, Egypt, Iraq, Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi Arabia, Syria, United Arab Emirates, Yemen, Gaza and the West Bank, Iran, Turkey, and Israel. The Middle East's population grew very little until 1990 when the population was 43 million. Population was about doubled in the mid-1950s at 80 million. Rapid growth occurred after 1950 with declines in mortality due to widespread disease control and sanitation efforts. Countries are grouped in the following ways: persistent high fertility and declining mortality with low to medium socioeconomic conditions (Jordan, Oman, Syria, Yemen, and the West Bank and Gaza), declining fertility and mortality in intermediate socioeconomic development (Egypt, Lebanon, Turkey, and Iran), high fertility and declining mortality in high socioeconomic conditions (Bahrain, Iraq, Kuwait, Qatar, Saudi Arabia, and the United Arab Emirates), and low fertility and mortality in average socioeconomic conditions (Israel). As birth and death rates decline, there is an accompanying shift from communicable diseases to degenerative diseases and increases in life expectancy; this pattern is reflected in the available data from Egypt, Kuwait, and Israel. High infant and child mortality tends to remain a problem throughout the Middle East, with the exception of Israel and the Gulf States. War casualties are undetermined, yet have not impeded the fastest growing population growth rate in the world. The average fertility is 5 births

  18. The determinants of early fertility decline in Texas.

    Science.gov (United States)

    Gutmann, M P; Fliess, K H

    1993-08-01

    This study examines the determinants of fertility control in a frontier population made up largely of German-Americans during the years from 1850 to 1910. The analysis employs a complex register of population constructed from census enumerations, civil and ecclesiastical vital registration, and tax assessment rolls. The article begins with a series of bivariate analyses with cohort of mother's birth, religion, ethnicity, and husband's occupation determining marital fertility. The second half of the paper presents a multivariate model of the determinants of fertility using these and other demographic characteristics as independent variables. The conclusions emphasize the importance of the overall trend toward fertility decline in the United States, as well as the role of religion and of occupational differences, in determining changes in fertility behavior in the population of Gillespie County, Texas.

  19. Analysis of the Relationship between CGB5 155G/C Polymorphism and in vitro Fertilization-embryo Transfer Outcome (IVF-ET in the Iranian Population

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    Bahareh Babaei Houlari

    2018-01-01

    Full Text Available Abstract Background: Successful pregnancy depends on the ability of the embryo to achieve appropriate extent of trophoblastic proliferation and invasion into maternal endometrium as well as, once implanted, to induce its own blood supply. Beta Human chorionic gonadotropin (β-hCG, enhances blastocyst implantation, uterine vascularization, and angiogenesis, as well as regulates maintenance of uterine quiescence and immunological adaptation during pregnancy. The β-subunit of hCG is encoded by CGB3, CGB6, CGB5, CGB7 and CGB8 genes. The aim of this study was to evaluate the association of CGB5-G/C polymorphism and the clinical outcomes in women who underwent IVF-ET procedures. Materials and Methods: A total of 200 patients undergoing IVF-ET (100 patients with positive and 100 patients with negative IVF-ET outcome were included in this study. Genotyping of CGB5 at -155G/C polymorphic site was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP. Statistical analysis was performed using the MedCalc software. Results: Our findings show that the CC genotype of the CGB5 -155G/C polymorphism is associated with decreased risk of IVF-ET failure (OR=0.29; 95%CI=0.1-0.85; p=0.02. However, the allelic distribution of the CGB5 -155G/C is not significantly different between two groups (χ2=1.46; p=0.22. Conclusion: The results of this study suggested that CGB5 (-155G/C CC genotype has a protective effect on IVF-ET outcome. More studies with larger sample sizes on different populations are necessary to elucidate the underlying mechanisms which can explain the associations found between the GGB5 gene polymorphisms and IVF-ET outcome.

  20. Perspectives of displaced Syrian women and service providers on fertility behaviour and available services in West Bekaa, Lebanon.

    Science.gov (United States)

    Kabakian-Khasholian, Tamar; Mourtada, Rima; Bashour, Hyam; Kak, Faysal El; Zurayk, Huda

    2017-10-01

    Prior to the conf