Full Text Available This chapter provides a detailed description of the fertility changes in Bulgaria during recent decades and discusses possible reasons and consequences. It also gives an overview of the steps that the government has undertaken to offset the considerable decline in fertility. Before the fall of communism, fertility trends in Bulgaria were stable and characterized by a nearly universal entry into parenthood, dominance of a two-child family model, an early start and early end of childbearing, stable mean ages at entry into childbearing and marriage, and low percentages of non-marital births. During the 1990s and in the first years of the new century, we observe a marked, rapid change in fertility behaviour. Together with the severe decline in overall fertility rates, demographic data reveal a significant postponement of entry into motherhood and marriage, a decline of the two-child family model, and an emergence of new family forms. Most research attributes these changes to the particular political and social situation in Bulgaria since 1989.
Wu, C; Jia, S
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
This dissertation focuses on the role of family and social relationships in individuals’ reproductive careers during the fertility decline in Soviet Ukraine from around 1950 to 1975. These three decades after the Second World War signified the end of the First Demographic Transition in Ukraine
Dribe, Martin; Breschi, Marco; Gagnon, Alain
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...
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.
Harrell, Stevan; Yuesheng, Wang; Hua, Han; Santos, Gonçalo D.; Yingying, Zhou
Many models have been proposed to explain both the rapidity of China’s fertility decline after the 1960s and the differential timing of the decline in different places. In particular, scholars argue over whether deliberate policies of fertility control, institutional changes, or general modernization factors contribute most to changes in fertility behavior. Here the authors adopt an ethnographically grounded behavioral–institutional approach to analyze qualitative and quantitative data from three different rural settings: Xiaoshan County in Zhejiang (East China), Ci County in Hebei (North China), and Yingde County in Guangdong (South China). The authors show that no one set of factors explains the differential timing and rapidity of the fertility decline in the three areas; rather they must explain differential timing by a combination of differences in social–cultural environments (e.g., spread of education, reproductive ideologies, and gender relations) and politico-economic conditions (e.g., economic development, birth planning campaigns, and collective systems of labor organization) during the early phases of the fertility decline. PMID:21319442
Cultural evolutionists have long been interested in the problem of why fertility declines as populations develop. By outlining plausible mechanistic links between individual decision-making, information flow in populations and competition between groups, models of cultural evolution offer a novel and powerful approach for integrating multiple levels of explanation of fertility transitions. However, only a modest number of models have been published. Their assumptions often differ from those in other evolutionary approaches to social behaviour, but their empirical predictions are often similar. Here I offer the first overview of cultural evolutionary research on demographic transition, critically compare it with approaches taken by other evolutionary researchers, identify gaps and overlaps, and highlight parallel debates in demography. I suggest that researchers divide their labour between three distinct phases of fertility decline—the origin, spread and maintenance of low fertility—each of which may be driven by different causal processes, at different scales, requiring different theoretical and empirical tools. A comparative, multi-level and mechanistic framework is essential for elucidating both the evolved aspects of our psychology that govern reproductive decision-making, and the social, ecological and cultural contingencies that precipitate and sustain fertility decline. PMID:27022079
Campbell, Martha M; Prata, Ndola; Potts, Malcolm
Although fertility decline often correlates with improvements in socioeconomic conditions, many demographers have found flaws in demographic transition theories that depend on changes in distal factors such as increased wealth or education. Human beings worldwide engage in sexual intercourse much more frequently than is needed to conceive the number of children they want, and for women who do not have access to the information and means they need to separate sex from childbearing, the default position is a large family. In many societies, male patriarchal drives to control female reproduction give rise to unnecessary medical rules constraining family planning (including safe abortion) or justifying child marriage. Widespread misinformation about contraception makes women afraid to adopt modern family planning. The barriers to family planning can be so deeply infused that for many women the idea of managing their fertility is not considered an option. Conversely, there is evidence that once family planning is introduced into a society, then it is normal consumer behaviour for individuals to welcome a new technology they had not wanted until it became realistically available. We contend that in societies free from child marriage, wherever women have access to a range of contraceptive methods, along with correct information and backed up by safe abortion, family size will always fall. Education and wealth can make the adoption of family planning easier, but they are not prerequisites for fertility decline. By contrast, access to family planning itself can accelerate economic development and the spread of education. PMID:23296851
Full Text Available RESUMENEste trabajo utiliza datos de las Encuestas Comparativas de Fecundidad de América Latina, así como de la Encuesta Mundial de Fecundidad para estudiar las tendencias y diferenciales en el espaciamiento de los nacimientos entre las mujeres alguna vez casadas en Costa Rica durante el período 1945-1974. Una buena parte de la atención se pone en el ritmo de la fecundidad en las etapas umbral, temprana y tardía de la disminución de la fecundidad que este país experimentó durante los años sesenta y principios de los setenta. Los resultados muestran bastante similitud en el tempo de la reproducción en los diferentes niveles paridez y áreas geográficas. Sin embargo, un análisis de las variables del entorno que afectan espaciamiento de los nacimientos muestra diferencias entre las zonas urbanas y rurales. Por último, se postula que el reciente estancamiento en las tasas de período puede ser una consecuencia de los cambios en el tempo de construcción de la familia, con mujeres de baja paridez que postergan los nacimientos, lo que contrarresta las tendencias de descenso que generan las mujeres de mayor paridez quienes aún pueden estar restringiendo su reproducción.ABSTRACTThis paper uses data from the Latin American Comparative Fertility Surveys as well as from the World Fertility Survey to study trends and differentials in birthspacing among ever married women in Costa Rica during the period 1945-1974. A good deal of attention is placed on the pace of fertility in threshold, early and late stages of the fertility decline that this country experienced during the sixties and early seventies. The results show a good deal of similarity in the tempo of reproduction across parities and geographical areas.However, an analysis of the background variables affecting birthspacing shows differences between urban and rural zones. Finally, it is postulated that the recent plateau in period rates may be a consequence of changes in the tempo of
In 1990, the Japanese were upset over the low 1989 total fertility rate (TFR) of 1.57 and continued to be so when they learned that the 1990 rate was even lower (1.53). This meant an annual population growth rate of only 0.33% with population decline beginning after 2010. In the early 1990s, Japan began to feel the demographic effects of such low fertility: a shortage of young workers and rising costs of health care for the elderly. Further, this shortage resulted in increasing business closings between 1988-1990 (1-6%). In 1990, the government began a survey to monitor the beliefs of the population on demographic concerns. The survey revealed that people wanted 2.2 children. Ideal family size was 2.6 which remained the same since 1977. Almost 40% found the falling TFR to be undesirable, especially because the population was aging. Moreover 65% of them though the government should undertake efforts to increase births. The major suggestions included reducing economic costs of raising a child (53%), a more favorable environment to have children such as affordable housing (29%), and developing child care facilities and child care leave (13%). 38% of 25-29 year old women were still unmarried, yet only 2% intended to never marry. Women in their late 20s and early 30s were critical of the 3 generation household with women doing all the housework. Women were more likely to be against premarital and extramarital sex than men. 25-33%, especially women 45 years old, felt the abortion law should be restricted. The 1990 abortion rate was 37.4/100 births. 7% relied on sterilization, yet 25-30% felt it to be an acceptable means of contraception. 75% of those that used a contraceptive used the condom. The government continued to ban oral contraceptives (OCs) claiming they would spread AIDS. Men were more in favor of OCs than women. 48% of those who found the falling population undesirable favored a pronatalist policy over importing foreign laborers. 41% wanted Japan to still help
Notkola, V; Nieminen, M
"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
The paper examines trends in the proximate determinants of fertility (nuptiality or marriage, contraception and post-partum infecundability) in Malawi during the twelve-year period 1992-2004, with a view to explaining the factors responsible for fertility decline in the country. The study uses the Malawi Demographic and ...
Pierre Claver Rutayisire
Full Text Available After having stalled in the 1990s, fertility in Rwanda resumed its downward trajectory between 2005 and 2010. The total fertility rate declined from 6.1 to 4.6 and modern contraceptive use increased. However, it is unclear which determinants lay behind the previous stall and the recent strong drop in fertility. This paper contributes to an ongoing debate on the impact of social upheavals on fertility decline. We use a decomposition analysis, focusing on the change in characteristics and reproductive behaviour of women and their contributions to levels of fertility during 1992–2000 and 2000–2010. Results show that due to widowhood and separation the proportion of women who were married decreased between 1992 and 2000, but their fertility increased in the same period due to replacement fertility and an unmet need for family planning. After 2000, postponement of marriage and lower infant mortality contributed to lower fertility, but the most important effect is the overall lower fertility due not only to improved family planning provision but perhaps also to the sensitizing campaigns of the Rwandan government.
Gutmann, M P; Fliess, K H
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.
Hovland, K H; Skogstad, M; Bakke, B; Skare, Ø; Skyberg, K
This study is part of a 3-year follow-up of lung function among nitrate fertilizer production workers. To study the possible adverse effects of occupational exposure to aerosols and gases on pulmonary diffusing capacity. A longitudinal study of a cohort of fertilizer workers who performed single-breath carbon monoxide diffusing capacity (DLco) tests and spirometry in 2007 and 2010. The workers completed a questionnaire on respiratory symptoms and smoking habits. Exposure to mineral dust, acid aerosols and inorganic gases was measured. The overall median inhalable and thoracic aerosol mass concentrations were 1.1mg/m(3) (min-max: <0.93-45) and 0.21mg/m(3) (min-max: <0.085-11), respectively. There were 308 participants in 2007 with 168 returning subjects in 2010. Overall, we found a statistically significant decline in the DLco of 0.068 mmol/min/kPa/year, adjusted for gender, age, height, weight, smoking status and doctor-diagnosed asthma during the 3-year follow-up (P < 0.01). The change in DLco did not vary significantly between the various job groups. Subjects with respiratory symptoms did not show a larger decline in DLco than those without symptoms. This study indicates a larger than expected decline in the DLco of fertilizer workers during a 3-year follow-up. However, the decline was not related to specific exposures at work, or to possible covariates of exposure.
Full Text Available Background: Consanguinity - or marriage between close blood relatives, in particular first cousins - is widely practised and even socially encouraged in many countries. However, in the face of fertility transition where the number of cousins eligible to marry declines, how might such constraints on consanguinity develop in the future? Objective: Numerous studies have stated that the practice cannot continue at present levels and in ist present form in the face of fertility transition. However, the future impact of fertility transition on availability of cousins to marry has not yet been quantified. Methods: We perform a simulation exercise using past and projected net reproduction rates (NRRs derived from the UN. We calculate the average number of cousins of the opposite sex as a function of the average number of children, the average probability of an individual having at least one eligible paternal cousin of the opposite sex, and conclude with an examination of constraints on consanguineous marriage in selected countries under different fertility assumptions. Results: Current and projected fertility levels in Middle Eastern countries will create challenging constraints on the custom once today's birth cohorts reach marriageable age. Conclusions: Either consanguinity prevalence will diminish significantly, or the institution will be forced to adapt by becoming more coercive in the face of reduced choice or at the expense of other social preferences (such as for an older groom wedding a younger bride. Fertility decline affects prospects for social change not only through its well-known consequences for mothers but also through shaping marriage conditions for the next generation.
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.
Schellekens, J.; van Poppel, F.W.A.
Previous studies of the fertility decline in Europe are often limited to an earlier stage of the marital fertility decline, when the decline tended to be slower and before the large increase in earnings in the 1920s. Starting in 1860 (before the onset of the decline), this study follows marital
Full Text Available EnglishThis article presents an overview of recent fertility declines and theireffectson social change in both industrialized and industrializing countries. Thefocus is primarily on the levels and age patterns of fertility, which influencesocial change through three major mechanisms, reductions in populationgrowth, modifications in age structure, and changes in family structure.Some future prospects are also discussed, especially in the view of theviability of immigration as a solution to population stability, graying of theindustrialized world, intergenerational support, and loneliness.FrenchCet article présente un survol de la baisse récente de fécondité et de seseffets sur les changements sociaux dans les pays industrialisés et les pays envoie d’industrialisation. L’article porte principalement sur les niveaux defécondité et la distribution de fécondité par âge, qui influent sur lechangement social par trois mécanismes importants, soit la réduction de lacroissance de la population, les modifications dans la structure par âge, ainsique les changements à la structure familiale. Il est question de certainesperspectives d’avenir, particulièrement en ce qui a trait à la viabilité del’immigration comme solution à la stabilité de la population, auvieillissement du monde industrialisé, au soutien intergénérationnel, et à lasolitude.
Wang, Cong; Madsen, Jakob; Moslehi, Solmaz
equality and low fertility. Standard fertility models extended with culture are estimated using data for 92 developing countries over the period 1960-2010. External instruments are used to deal with endogeneity. It is found that secularization and reduced infant mortality can explain the bulk...... of the fertility decline between 1960 and 2010, while income, urbanization and female education have not been robust determinants of the fertility decline....
Schellekens, Jona; van Poppel, Frans
Previous studies of the fertility decline in Europe are often limited to an earlier stage of the marital fertility decline, when the decline tended to be slower and before the large increase in earnings in the 1920s. Starting in 1860 (before the onset of the decline), this study follows marital fertility trends until 1939, when fertility reached lower levels than ever before. Using data from the Historical Sample of the Netherlands (HSN), this study shows that mortality decline, a rise in real income, and unemployment account for the decline in the Netherlands. This finding suggests that marital fertility decline was an adjustment to social and economic change, leaving little room for attitudinal change that is independent of social and economic change.
Prettner, Klaus; Bloom, David E; Strulik, Holger
It is widely argued that declining fertility slows the pace of economic growth in industrialized countries through its negative effect on labor supply. There are, however, theoretical arguments suggesting that the effect of falling fertility on effective labor supply can be offset by associated behavioral changes. We formalize these arguments by setting forth a dynamic consumer optimization model that incorporates endogenous fertility as well as endogenous education and health investments. The model shows that a fertility decline induces higher education and health investments that are able to compensate for declining fertility under certain circumstances. We assess the theoretical implications by investigating panel data for 118 countries over the period 1980 to 2005 and show that behavioral changes partly mitigate the negative impact of declining fertility on effective labor supply.
In their article published in the â€œNatureâ€ journal, Myrskylä et al. (2009) claimed that in highly developed countries development-fertility relationship becomes J-shaped. This means that further advances in economic and social development can reverse declining fertility rates. The present paper employs threshold regression analysis (Hansen 2000) to examine the existence of the proposed J-shaped fertility-development curve. The findings indicate that the threshold value of human development...
Full Text Available BACKGROUND An important question for population research is whether fertility decline transforms gender systems. OBJECTIVE This paper contributes to answering this broad question by examining how fertility decline may change the relative value and roles of daughters versus sons in families. First, I outline theoretical pathways, suggesting that a key factor is the gender composition of families. As fertility declines, the proportion of families with children of only one gender increases, which may facilitate greater gender symmetry between daughters and sons. Second, I explore how fertility decline may be transforming the relative value and roles of sons and daughters in practice in one place. METHODS The analysis draws primarily on semi-structured interviews with 30 respondents living in one Indian village. RESULTS In recent decades, fertility has declined to at least replacement levels. Respondents also perceive changes in the gender system, including less son preference, more equal schooling for sons and daughters, more freedom in marriage and pre-marital relationships, and perhaps greater daughter support of parents in old age. CONCLUSIONS The results describe changes in the relative value, treatment, and behavior of sons and daughters that are consistent with the theorized effects of fertility decline. Future research is needed, however, to determine whether fertility decline makes a unique causal contribution to changes in the gender system.
Lindstrom, D P; Berhanu, B
We examine recent fertility trends in Ethiopia for evidence of short- and long-term responses to famine, political events, and economic decline. We use retrospective data on children ever born from the 1990 National Family and Fertility Survey to estimate trends in annual marital conception probabilities, controlling for women's demographic and socioeconomic characteristics. The results of our analysis provide evidence of significant short-term declines in conception probabilities during years of famine and major political and economic upheaval. In the longer term, marital fertility in both urban and rural areas declined in the 1980s after increasing moderately in the 1970s.
Bangladesh has a population of 115 million people, and the economic growth rate of 3.7% during the 1980s was undermined by rapid population growth. The annual population growth rate was 3% in the 1960s and early 1970s, 2.5% between 1981-91 decreasing to 2.3% in 1991. The average of number of children is 4.6/woman compared with 7 in the 1960s. Infant mortality dropped from 150/1000 births in 1976 to 118/1000 in 1991. Life expectancy rose from 47 to 54 years. The 1991 Contraceptive Prevalence Survey showed that 39.9% of married women under 50 use contraceptives in 1991 vs. 18.6% in 1981. The use of modern methods increased from 10.9% in 1981 to 31.2% in 1991, while traditional methods rose from 7.7% to 8.7%. Sterilization was most prevalent in 1981. 29,000 female family planning (FP) workers were aggressively engaged in dispensing FP services in 1990. The Social Marketing Company sells pills, condoms, and oral rehydration salts through 130,000 retail outlets. The 1989 Contraceptive Prevalence Survey showed that 40% of pill and condom users obtained them from this network, and 95.4% of women knew about 4 methods of contraception. In 1990 there were 120 private organizations providing contraceptive services. Some of the components of the government FP program include field worker distribution door-to-door of injectable contraceptives (50% injectable usage rate in the Matlab project); recordkeeping activities; a satellite clinic network with access to contraceptive services; and decentralization through the Upazila (subdistrict) approach. The logistics system of FP has improved the warehousing, transportation, and management information system. Foreign aid (mainly USAID) financing of contraceptives helped avert 14.4 million births between 1974-90. The increase of contraceptive prevalence to 50% by 1997 would avert another 21.9 million births during 1991-96 (replacement fertility requires 70% prevalence.
Botswana has had a stable democratic government and good governance since independence in 1966. With a sustained high average economic growth (about 9 percent) fueled by the diamond mining industry, it is the only country in Africa listed among the 13 'economic miracles' of the world for 1960-2005. The total fertility rate remains high in Sub-Saharan Africa, with 25 countries showing a rat...
Full Text Available In this study, we demonstrate from different angles that Hungarian fertility basically decreased between 1965 and 2005, but also clearly fluctuated, and showed different patterns in the different periods within this epoch. As a result, the clear communist-era family pattern of "early marriage and childbearing with two children" was replaced, but new family model(s have not yet fully emerged. We could show that profound changes in partnership behaviour -divorce and cohabitation- started before the change of the political regime, but also that changes in partnership relations accelerated after 1990, and that partnerships have become more fragile. In addition, Western-style values of "empty individualism" and consumerism were clearly present under socialism, but their motivating force was tamed by the communist system, in which population policy played a significant role. Of these institutional changes, we ascribe the greatest importance to the expansion in the educational system and the changes in the labour market. We show that, following the changes in the economic system, the conflict between family and work intensified. The synchronic consideration of values, labour market relations, economic development, and population policy; and the relationship of these factors to fertility and nuptiality trends, enabled us to formulate a developmental scheme of four phases concerning the evolution of fertility since 1965.
Colleran, Heidi; Jasienska, Grazyna; Nenko, Ilona; Galbarczyk, Andrzej; Mace, Ruth
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.
Wang, Qingfeng; Sun, Xu
.... * Political freedom is found to play a role in shaping people's perceptions of fertility. * Human capital is confirmed to be the most important determinants in explaining the decline in fertility...
Full Text Available Background: The effects of an economic recession extend beyond financial spheres and spill over into present and future family decisions via income restrictions and expectations. Hardly any research on the effects of economic recession on fertility outcomes has taken place in developing countries. Objective: This study seeks to explain the effects of economic cycles on fertility outcomes in poor areas. Methods: This paper analyzes fertility trends from the third largest economy in Latin America - Colombia - from 1998 to 2013. We estimate a panel data regression model with state and year fixed effects. Results: On average, periods of recession are associated with fertility decline in poor areas and fertility growth in well-off areas. During an economic crisis, fertility in poor states decreases by 0.002 children per woman, while in well-off states fertility increases by 0.007 children per woman. Conclusions: The impact of an economic crisis on fertility varies depending on poverty. Poor states have procyclical responses while well-off states tend to have countercyclical reactions to economic downturns. Contribution: This study illuminates the procyclical and countercyclical debate, showing that within a country there can be two different responses to an economic downturn.
Soil fertility decline is perceived to be widespread in the upland soils of the tropics, particularly in sub-Saharan Africa. Most studies have used nutrient balances to assess the degree and extent of nutrient depletion; these have created awareness but suffer methodological problems as several of
Hovland, Kristin H; Skogstad, Marit; Bakke, Berit; Skare, Oivind; Skyberg, Knut
This study examines the possible effect of exposure to aerosols and gases on lung function in a fertilizer plant in Norway. Dynamic lung volumes (FVC and FEV1) of 383 workers were measured in 2007 and 2010. During the follow-up period, most workers performed tasks with low exposure levels of acid aerosols and inorganic gases. The overall median inhalable and thoracic aerosol exposure levels were 1·1 and 0·21 mg/m(3), respectively. A questionnaire on respiratory symptoms was provided. During the follow-up period, there was an adjusted decrease of FEV1 of 18 ml/year (P<0·001). The respiratory symptoms score was low during follow-up. Work in this fertilizer industry may lead to an excessive lung function decline. We have, however, not been able to find any plausible exposure related explanation for the overall lung function decline.
Goto, Aya; Yasumura, Seiji; Yabe, Junko; Reich, Michael R
Japan has been experiencing a continuing decline in fertility and an increase in premarital conceptions and abortions among young people. Child rearing is often viewed as a burden. In response, Japan is now seeking ways to improve the child-rearing environment for parents. In this context, we conducted a prospective study among 206 pregnant women in Sukagawa City, Fukushima, to explore the influences of pregnancy intention on child rearing. We found that unintended pregnancy was associated with a higher risk of negative child-rearing outcomes, including lower mother-to-child attachment, increased negative feelings of mothers and a lower level of participation of fathers in child rearing. Unintended pregnancy exacerbates the real and perceived burdens of child rearing. Japan is currently facing a conflict between wanting to reduce unintended pregnancies and increase the national fertility rate. We believe the government needs to address the social challenges affecting people's family lives, which underpin low fertility, rather than focus on fertility decline per se. We suggest Japan seeks to reduce unintended pregnancies and provide support to parents at high risk of child-rearing difficulties. We also suggest adopting a comprehensive approach to improving the lives of young couples, with a focus on adolescents, including life-skills education to prepare for adulthood, marriage and parenthood.
de Groot, Marije; Dancet, Eline; Repping, Sjoerd; Goddijn, Mariette; Stoop, Dominic; van der Veen, Fulco; Gerrits, Trudie
Women can now opt to bank their oocytes with the intention of increasing their chances of achieving a pregnancy after their fertility has declined. This exploratory study aimed to gain insight into how women, considering oocyte banking to circumvent age-related fertility decline, perceive this intervention. We conducted a qualitative study in a Dutch university medical center and held in-depth interviews with women on the waiting list for oocyte banking. We recorded the interviews, transcribed them verbatim and used thematic analysis. All women were financially independent and lived in single-person urban households. They opted for oocyte banking because they wished to share parenthood with a future partner rather than becoming a single parent. This strong desire was key in their interpretation of all aspects of the intervention. Women set aside information about the limited success rates and potential risks, as they were optimistic about their own prognosis, thought that the chances for success were equally likely as the chances it would fail, and because of "anticipatory regret". They perceived oocyte banking as a "helping hand" to achieve shared parenthood. Although women found the costs of the intervention high, they were willing to invest their money to increase their chances for shared parenthood. Oocyte banking allows women to circumvent age-related fertility decline. The prospect of potential shared parenthood overrules the perceived health risks and burden. Health professionals should take this into account when informing potential users of oocyte banking. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.
Gurmu, Eshetu; Mace, Ruth
Demographic transition theory states that fertility declines in response to development, thus wealth and fertility are negatively correlated. Evolutionary theory, however, suggests a positive relationship between wealth and fertility. Fertility transition as a result of industrialization and economic development started in the late 19th and early 20th centuries in Western Europe; and it extended to some of the Asian and Latin American countries later on. However, economic crises since the 1980s have been co-incident with fertility decline in sub-Sahara Africa and other developing countries like Thailand, Nepal and Bangladesh in the last decade of the 20th century. A very low level of fertility is observed in Addis Ababa (TFR=1.9) where contraceptive prevalence rate is modest and recurrent famine as well as drought have been major causes of economic crisis in the country for more than three consecutive decades, which is surprising given the high rural fertility. Detailed socioeconomic and demographic characteristics of 2976 women of reproductive age (i.e. 15-49 years) residing in Addis Ababa were collected during the first quarter of 2003 using an event history calendar and individual women questionnaire. Controlling for the confounding effects of maternal birth cohort, education, marital status and accessible income level, the poor (those who have access to less than a dollar per day or 250 birr a month) were observed to elongate the timing of having first and second births, while relatively better-off women were found to have shorter birth intervals. Results were also the same among the ever-married women only model. More than 50% of women currently in their 20s are also predicted to fail to reproduce as most of the unmarried men and women are 'retreating from marriage' due to economic stress. Qualitative information collected through focus group discussions and in-depth interviews also supports the statistical findings that poverty is at the root of this collapse
Kane, T T
In Gambia, more than 50% of the population is less than 20 years old. Adolescent fertility comprises 15% of total fertility. It is linked with certain health problems and socioeconomic problems. Adolescent fertility contributes to population growth and can influence socioeconomic development and the level of mortality risks among reproductive age women and their children. In 1983, the total fertility rate for Gambia was 6.4 births per woman compared to 6.5 in 1973. In the urban areas of Banjul and Kombo St. Mary Districts, it was 5.5 and 5.6, respectively. In Gambia overall, women have on average one child during adolescence. In metropolitan Banjul, 61% of all sexually active women and 37% of all sexually active single women had a child during adolescence. 40% of married girls aged 14-15 have been pregnant at least once. Based on the 1983 census, fertility among 15-19 year olds in metropolitan Banjul was 148 births/1000 women. In 1973, it was 199/1000 nationwide. The 1986-1987 fertility survey found their fertility to be 113/1000 based on registered births. Increase of the mean marriage age, higher educational level, and more contraceptive use in metropolitan Banjul may explain the decline in adolescent fertility here. 23% of women aged 15-19 in metropolitan Banjul were married in 1987 compared to 30% in 1983 and 53% for all Gambia in 1987. During 1986-1987, 83% of unschooled 19 year old females in greater Banjul were married compared to 13% of same-aged females with at least 7 years of education. In all of Gambia in 1983, women aged 15-19 with primary education had a fertility rate more than two times greater than that of same-aged women with superior education (220 vs. 103/1000). Adolescent fertility can limit education possibilities and darken economic perspectives. As societies continue to develop and modernize, it will be important to survey adolescent fertility and its socioeconomic and health impact on all youth as well as on the rest of society.
David Shapiro; Michel Tenikue
Background: This paper provides estimates of the contributions of increased women's education and reduced infant and child mortality to fertility declines in urban and rural areas of countries in Sub-Saharan...
Full Text Available This article opens with a review of the main trends in family-related behaviour, i.e. fertility decline and changes in fertility patterns, a decreasing propensity to marry, postponement of marriage, and a slowly increasing frequency of divorces and separations. The analysis takes into account urban and rural differences. We then aim to identify the main determinants of family changes within the general conceptual framework of the Second Democratic Transition (SDT in Poland. However, contrary to mainstream interpretations of the SDT, the main emphasis of this study is on the structural components of change, which need to be reformulated to account for processes specific to the transition to a market economy. The focus is, therefore, on labour market developments and family policy, and to a lesser extent on ideational change.
Roy, Helen E.; Adriaens, Tim; Isaac, Nick J.B.
Aim Invasive alien species (IAS) are recognized as major drivers of biodiversity loss, but few causal relationships between IAS and species declines have been documented. In this study, we compare the distribution (Belgium and Britain) and abundance (Belgium, Britain and Switzerland) of formerly...
Geoff M. Hilton; Phil W. Atkinson; Gerard A.L. Gray; Wayne J. Arendt; David W. Gibbons
Prior to 1995, the Montserrat oriole (Icterus oberi) was confined to ca. 30 km2 of hill forest on the Lesser Antillean island of Montserrat, but was not listed as globally threatened. Since then, the eruption of the Soufriere Hills volcano has destroyed more than half of the speciesâ range. Recent intensive monitoring has indicated that the species has also declined...
Tiemann, L. K.; Hartter, J.; Grandy, S.
Food security issues are particularly acute in Uganda, where the world's 8th highest population growth rate will lead to cultivation of all land available for agriculture by 2022. Agricultural intensification in Uganda, which includes continuous cropping, mono-cropping and expansion of agriculture into marginal areas, has put unprecedented pressure on soils. In western Uganda, we surveyed 474 households, collecting demographic data, information on land use practices and perceptions of risk to crop yields and food security. We also sampled soils from maize fields associated with each surveyed household and measured total organic C and nutrients such as nitrogen (N) and phosphorus (P). Using these data, we sought to determine how risk perceptions, ethnicity, household wealth and education combine to determine land use decisions and ultimately, declines in soil organic matter and soil nutrients. We conducted our study within 5 km of an un-cultivated native tropical forest reserve, Kibale National Park (KNP), which serves as a reference point for potential soil fertility. Of 470 respondents, only 29 answered `no' when asked if they noticed year to year declines in crop yields. Across all maize fields we found soil C has been reduced by 30% and soil N by 45% relative to KNP soils and declines were more pronounced when survey respondents were Bakiga rather than Batooro. Households that indicated they were "very much" dependent upon profits from maize had a 31% increase in soil C:N while those indicating no dependence on maize profits had a significantly lower increase in soil C:N of 21%. Ethnicity and education influenced land use decisions; the Batooro and people with a lower level of education were more likely to burn their fields or crop residues. Additionally, the Bakiga were more likely to use rock P in their fields and in consequence had 108% while Batooro soils had 65% of the P found in KNP soils. Across all respondents, the top two ranked risks to crop yields and
Sadanandavalli Retnaswami Chandra
Full Text Available Background: Dementias are fairly slowly progressive degenerative diseases of brain for which treatment options are very less and carry a lot of burden on family and society. A small percentage of them are rapidly progressive and mostly carry a different course outcome. However, there are no definite criteria other than the time line for these patients. Aims: The aim of this was to identify and categorize the causes and course of rapidly progressive dementias seen in our center. Settings and Design: Patients who presented with rapid deterioration of cognitive functions within weeks to 1 year between 2011 and December 2016 were evaluated. Patients and Methods: All patients underwent all mandatory tests for dementia including brain imaging. Complete vasculitis workup, autoimmune encephalitis profile including Voltage Gated Potassium Channel, N-methyl-D-aspartic acid receptor, glutamic acid-decarboxylase, thyroid-peroxidase antibody, cerebrospinal fluid, and other special tests such as duodenal biopsy and paraneoplastic workup were done based on clinical indications. Results and Conclusions: Out of 144 patients 42 had immune-mediated encephalopathy, 18 had Creutzfeldt-Jakob disease, 3 had Vitamin B12 deficiency, 63 had infection with neurocysticercosis, 7 had tuberculosis, 2 had HIV, 1 had herpes simplex encephalitis, 1 had neurosyphilis, 1 Whipples disease, 1 had Subacute Sclerosing Panencephalitis, 1 had Mass lesion, 3 had Frontotemporal dementia, and 3 had small vessel disease. Good majority of these patients have infective and immune-mediated causes and less number belong to degenerative group. Therefore, caution is needed to look for treatable cause as it carries a different treatment options and outcome.
Butchart, Stuart H. M; Stattersfield, Alison J; Bennun, Leon A; Shutes, Sue M; Akçakaya, H. Resit; Baillie, Jonathan E. M; Stuart, Simon N; Hilton-Taylor, Craig; Mace, Georgina M
The rapid destruction of the planet's biodiversity has prompted the nations of the world to set a target of achieving a significant reduction in the rate of loss of biodiversity by 2010. However, we do not yet have an adequate way of monitoring progress towards achieving this target. Here we present a method for producing indices based on the IUCN Red List to chart the overall threat status (projected relative extinction risk) of all the world's bird species from 1988 to 2004. Red List Indice...
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
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.
Full Text Available We examined the overall contributions of the poor and non-poor in fertility decline across the Asian countries. Further, we analyzed the direct and indirect factors that determine the reproductive behaviour of two distinct population sub-groups.Data from several new rounds of DHS surveys are available over the past few years. The DHS provides cross-nationally comparable and useful data on fertility, family planning, maternal and child health along with the other information. Six selected Asian countries namely: Bangladesh, India, Indonesia, Nepal, Philippines, and Vietnam are considered for the purpose of the study. Three rounds of DHS surveys for each country (except Vietnam are considered in the present study.Economic status is measured by computing a "wealth index", i.e. a composite indicator constructed by aggregating data on asset ownership and housing characteristics using principal components analysis (PCA. Computed household wealth index has been broken into three equal parts (33.3 percent each and the lowest and the highest 33.3 percent is considered as poor and non-poor respectively. The Bongaarts model was employed to quantify the contribution of each of the proximate determinants of fertility among poor and non-poor women.Fertility reduction across all population subgroups is now an established fact despite the diversity in the level of socio-economic development in Asian countries. It is clear from the analysis that fertility has declined irrespective of economic status at varying degrees within and across the countries which can be attributed to the increasing level of contraceptive use especially among poor women. Over the period of time changing marriage pattern and induced abortion are playing an important role in reducing fertility among poor women.Fertility decline among majority of the poor women across the Asian countries is accompanied by high prevalence of contraceptive use followed by changing marriage pattern and induced
Beemsterboer, S N; Homburg, R; Gorter, N A; Schats, R; Hompes, P G A; Lambalk, C B
Advancing female age is associated with declining fertility potential due to decreasing numbers and quality of oocytes but also with a distinct increase in dizygotic twinning rates, a phenomenon that has never been explained. An analysis of follicle development was made in 959 spontaneous ovulatory cycles of 507 women. Multiple ovarian follicular development (>1 follicle >14 mm) and, by implication, multiple rather than single ovulations occurred in 105 women whose mean age (36.1 versus 34.6 years) and mean basal FSH concentrations (10.3 versus 7.7 IU/l) were significantly greater than those with monofollicular development (P twinning must be associated with the development of >1 large follicle, which we found to be a significantly more frequent occurrence in older women. It is hypothesized that the response of pituitary release of FSH to the decreased negative feedback induced by impending ovarian failure often 'overshoots', causing multiple follicular development. In the presence of two good-quality oocytes, a twin pregnancy may result.
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
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
Infesta Dominquez, G
This article gives an overview of a conference on Fertility and the Male Life Cycle held in Mexico on November 13-16, 1995. The seminars, organized by anthropological demographers, were based on the view that differences in men's life course events affect how many children are produced, when children are produced, and the kind of support given to children. Little research has focused on male fertility. Two overview papers addressed the issues of men's changing sexual and reproductive intentions as a response to economic changes (Jane Guyer) and theories of male fertility trends in industrialized countries (David Coleman). Other papers were presented on the following topics: changes in male fertility, sexuality and the male life cycle, polygyny and fertility, men's notions of sexuality and reproductive health, masculinity and reproduction, and future research directions. Laurent Toulemon and Evelyne Lapierre-Adamcyk and Katarina Pohl presented papers on gender differences in fertility. Philip Setel presented an analysis of the social construction of parenthood among Coastal Boiken in Papua New Guinea. Paul Miret discussed men's role in the sharp decline in Spanish fertility. Nosa Orobaton contrasted African men's changing roles over the life course. Differences in fertility among polygynous populations in Africa and in China were analyzed by Ann Blanc and Anastasia Gage, and James Lee and Wang Feng. Other papers were prepared by Juan Gillermo Figueroa Perea, John Anarfi and Clara Korkor, Frances L. Goldscheider et al., Benno de Keijzer, and Mario Humberto Ruz, Ondina Fachel Leal and Jandyra M.G. Fachel, and Kamran Asdar Ali. Seminar papers were expected to be published in several collections.
The analysis of recent fertility trends in France lead to hold as plausible that women born after 1950 will not reach replacement level. On the other hand, the period total fertility rate, which has not fallen as low as those observed in some neighbouring countries, might well continue to decline and thus disturb the alimentation of age-pyramid, despite its slower decrease in the course of 1976. Considering present fertility situation in France, an action of the State appears to be desirable. The factors which condition fertility fall largely out of the range of well-established knowledge. Though, it seems that they are deeply rooted in collective consciousness and that the possibilities they leave to voluntary action on fertility trends is relatively modest. Moreover, to be efficient, the means used must be important. The lines of possible action seem, in our view, to relate to two main fields: research of a better conciliation of professional activity and motherhood, increase of family benefits for second but specially for third and following children.
Dado, Shlomo; De Rújula, Alvaro
Many gamma ray bursts (GRBs) have been observed with the Burst-Alert and X-Ray telescopes of the SWIFT satellite. The successive `pulses' of these GRBs end with a fast decline and a fast spectral softening, until they are overtaken by another pulse, or the last pulse's decline is overtaken by a less rapidly-varying `afterglow'. The fast decline-phase has been attributed, in the standard fireball model of GRBs, to `high-latitude' synchrotron emission from a collision of two conical shells. This interpretation does not agree with the observed spectral softening. The temporal behaviour and the spectral evolution during the fast-decline phase agree with the predictions of the cannonball model of GRBs.
This paper aimed to examine the debate over the fertility decline in the German Empire, focusing on the role of the SPD. During the German Empire, the fertility rate dramatically declined and the growing awareness of a continuous decline in the birth rate prompted a massive debate among politicians, doctors, sociologists, and feminist activists. The fertility decline was negatively evaluated and generated consciousness of crisis. However, it was not the only way to face this new phenomenon. Indeed, the use of birth control among the upper class was interpreted as a part of a modernizing process. As the same phenomenon reached the working class, it suddenly became a social problem and was attributed to the SPD. The debate over the fertility decline in imperial German society ridden with a fierce class conflict was developed into a weapon against the SPD. Contrary to the assumption of conservative politicians, the SPD had no clear-cut position on this issue. Except for a few politicians like Kautsky and the doctors who came into frequent contact with the workers, the "birth strike" was not listed as the main interest of the SPD. Even Clara Zetkin, the leader of the Social Democratic women's organization viewed it as a concern of the individual person which could not be incorporated in the party program. The women's organization of the SPD put priority on class conflict rather than issues specific to women. As a result, the debate over the birth rate decline within the SPD was not led by the women themselves. There could have been various means to stimulate the birth rate. Improvement in the welfare system, such as tax relief for large families, better housing conditions, and substantial maternity protection, could have been feasible solutions to the demographic crisis. However, Germany chose to respond to this crisis by imposing legal sanctions against birth control. In addition to paragraphs 218-220 of the German criminal law enacted in 1872 which prescribed penal
O'Neill, BC; Scherbov, S; Lutz, W
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
Buchman, Aron S; Wilson, Robert S; Yu, Lei; James, Bryan D; Boyle, Patricia A; Bennett, David A
Longitudinal studies of objectively measured physical activity are lacking in older adults. We tested whether objective measures of total daily activity decline more rapidly in older adults. This prospective, observational cohort study included 519 community-dwelling older persons from across metropolitan Chicago participating in the Rush Memory and Aging Project. Repeated total daily activity measures (leisure and non-leisure physical activity) were derived from actigraphic recordings for up to 10 days. Generalized estimating equation models which controlled for demographics measures were employed. At baseline, age was inversely related with the level of total daily activity (estimate, -0.014, S.E. 0.002, pdaily activity declined by about 0.070 × 10(5) activity counts/day/yr (estimate -0.065, S.E. 0.005, pdaily activity declined 3% more rapidly for each additional year of age at baseline (estimate -0.002, S.E. 0.001, p=0.027). Thus, total daily activity declined almost twice as fast in an individual 91 years old at baseline versus an individual 71 years old. A higher level of education was associated with a slower rate of decline (estimate 0.004, S.E. 0.002, pdaily activity were unchanged when controlling for baseline level of motor and cognitive function, other late-life activities and chronic health conditions. These data suggest that total daily activity in very old adults declines more rapidly with increasing age. Thus, physical inactivity is likely to become a larger problem in our aging population. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Liu, Xiang; Lyu, Shengman; Sun, Dexin; Bradshaw, Corey J A; Zhou, Shurong
The artificial fertilization of soils can alter the structure of natural plant communities and exacerbate pathogen emergence and transmission. Although the direct effects of fertilization on disease resistance in plants have received some research attention, its indirect effects of altered community structure on the severity of fungal disease infection remain largely uninvestigated. We designed manipulation experiments in natural assemblages of Tibetan alpine meadow vegetation along a nitrogen-fertilization gradient over 5 years to compare the relative importance of direct and indirect effects of fertilization on foliar fungal infections at the community level. We found that species with lower proneness to pathogens were more likely to be extirpated following fertilization, such that community-level competence of disease, and thus community pathogen load, increased with the intensity of fertilization. The amount of nitrogen added (direct effect) and community disease competence (indirect effect) provided the most parsimonious combination of parameters explaining the variation in disease severity. Our experiment provides a mechanistic explanation for the dilution effect in fertilized, natural assemblages in a highly specific pathogen-host system, and thus insights into the consequences of human ecosystem modifications on the dynamics of infectious diseases. © 2017 The Author(s).
Jensen, Tina Kold; Carlsen, Elisabeth; Jørgensen, Niels
to changing social structures alone or is a reduced fecundity in the population also a factor? To address this we have focused on trends in teenage pregnancies (which to a large extent are unplanned). During the period in question fertility rates among 15-19 year old Danish women have been falling...... may not be attributable to social factors, changes in conception practices or diminished sexual activity alone. It seems reasonable also to consider widespread poor semen quality among men as a potential contributing factor to low fertility rates among teenagers. Due to the concern caused by the low...
This study examines rural people's knowledge in changing conditions such as decreasing soil fertility and increasing population. It explores how farmers, who depend on rainfed agriculture and are confronted with an ever increasing population, react. The study presents the case of an ethnic
Timothy Y James
Full Text Available The fungal disease chytridiomycosis, caused by Batrachochytrium dendrobatidis, is enigmatic because it occurs globally in both declining and apparently healthy (non-declining amphibian populations. This distribution has fueled debate concerning whether, in sites where it has recently been found, the pathogen was introduced or is endemic. In this study, we addressed the molecular population genetics of a global collection of fungal strains from both declining and healthy amphibian populations using DNA sequence variation from 17 nuclear loci and a large fragment from the mitochondrial genome. We found a low rate of DNA polymorphism, with only two sequence alleles detected at each locus, but a high diversity of diploid genotypes. Half of the loci displayed an excess of heterozygous genotypes, consistent with a primarily clonal mode of reproduction. Despite the absence of obvious sex, genotypic diversity was high (44 unique genotypes out of 59 strains. We provide evidence that the observed genotypic variation can be generated by loss of heterozygosity through mitotic recombination. One strain isolated from a bullfrog possessed as much allelic diversity as the entire global sample, suggesting the current epidemic can be traced back to the outbreak of a single clonal lineage. These data are consistent with the current chytridiomycosis epidemic resulting from a novel pathogen undergoing a rapid and recent range expansion. The widespread occurrence of the same lineage in both healthy and declining populations suggests that the outcome of the disease is contingent on environmental factors and host resistance.
Bragina, Eugenia V; Ives, A R; Pidgeon, A M; Kuemmerle, T; Baskin, L M; Gubar, Y P; Piquer-Rodríguez, M; Keuler, N S; Petrosyan, V G; Radeloff, V C
Anecdotal evidence suggests that socioeconomic shocks strongly affect wildlife populations, but quantitative evidence is sparse. The collapse of socialism in Russia in 1991 caused a major socioeconomic shock, including a sharp increase in poverty. We analyzed population trends of 8 large mammals in Russia from 1981 to 2010 (i.e., before and after the collapse). We hypothesized that the collapse would first cause population declines, primarily due to overexploitation, and then population increases due to adaptation of wildlife to new environments following the collapse. The long-term Database of the Russian Federal Agency of Game Mammal Monitoring, consisting of up to 50,000 transects that are monitored annually, provided an exceptional data set for investigating these population trends. Three species showed strong declines in population growth rates in the decade following the collapse, while grey wolf (Canis lupus) increased by more than 150%. After 2000 some trends reversed. For example, roe deer (Capreolus spp.) abundance in 2010 was the highest of any period in our study. Likely reasons for the population declines in the 1990s include poaching and the erosion of wildlife protection enforcement. The rapid increase of the grey wolf populations is likely due to the cessation of governmental population control. In general, the widespread declines in wildlife populations after the collapse of the Soviet Union highlight the magnitude of the effects that socioeconomic shocks can have on wildlife populations and the possible need for special conservation efforts during such times. © 2015 Society for Conservation Biology.
Colleran, Heidi; Jasienska, Grazyna; Nenko, Ilona; Galbarczyk, Andrzej; Mace, Ruth
In the course of demographic transitions (DTs), two large-scale trends become apparent: (i) the broadly positive association between wealth, status and fertility tends to reverse, and (ii) wealth inequalities increase and then temporarily decrease. We argue that these two broad patterns are linked, through a diversification of reproductive strategies that subsequently converge as populations consume more, become less self-sufficient and increasingly depend on education as a route to socio-economic status. We examine these links using data from 22 mid-transition communities in rural Poland. We identify changing relationships between fertility and multiple measures of wealth, status and inequality. Wealth and status generally have opposing effects on fertility, but these associations vary by community. Where farming remains a viable livelihood, reproductive strategies typical of both pre- and post-DT populations coexist. Fertility is lower and less variable in communities with lower wealth inequality, and macro-level patterns in inequality are generally reproduced at the community level. Our results provide a detailed insight into the changing dynamics of wealth, status and inequality that accompany DTs at the community level where peoples' social and economic interactions typically take place. We find no evidence to suggest that women with the most educational capital gain wealth advantages from reducing fertility, nor that higher educational capital delays the onset of childbearing in this population. Rather, these patterns reflect changing reproductive preferences during a period of profound economic and social change, with implications for our understanding of reproductive and socio-economic inequalities in transitioning populations. PMID:25833859
Colleran, Heidi; Jasienska, Grazyna; Nenko, Ilona; Galbarczyk, Andrzej; Mace, Ruth
In the course of demographic transitions (DTs), two large-scale trends become apparent: (i) the broadly positive association between wealth, status and fertility tends to reverse, and (ii) wealth inequalities increase and then temporarily decrease. We argue that these two broad patterns are linked, through a diversification of reproductive strategies that subsequently converge as populations consume more, become less self-sufficient and increasingly depend on education as a route to socio-economic status. We examine these links using data from 22 mid-transition communities in rural Poland. We identify changing relationships between fertility and multiple measures of wealth, status and inequality. Wealth and status generally have opposing effects on fertility, but these associations vary by community. Where farming remains a viable livelihood, reproductive strategies typical of both pre- and post-DT populations coexist. Fertility is lower and less variable in communities with lower wealth inequality, and macro-level patterns in inequality are generally reproduced at the community level. Our results provide a detailed insight into the changing dynamics of wealth, status and inequality that accompany DTs at the community level where peoples' social and economic interactions typically take place. We find no evidence to suggest that women with the most educational capital gain wealth advantages from reducing fertility, nor that higher educational capital delays the onset of childbearing in this population. Rather, these patterns reflect changing reproductive preferences during a period of profound economic and social change, with implications for our understanding of reproductive and socio-economic inequalities in transitioning populations.
Oakley, K.; Whalen, M.; Douglas, D.; Udevitz, M.; Atwood, T.; Jay, C.
The Arctic is warming faster than other regions of the world due to positive climate feedbacks associated with loss of snow and ice. One highly visible consequence has been a rapid decline in Arctic sea ice over the past 3 decades - a decline projected to continue and result in ice-free summers likely as soon as 2030. The polar bear (Ursus maritimus) and the Pacific walrus (Odobenus rosmarus divergens) are dependent on sea ice over the continental shelves of the Arctic Ocean's marginal seas. The continental shelves are shallow regions with high biological productivity, supporting abundant marine life within the water column and on the sea floor. Polar bears use sea ice as a platform for hunting ice seals; walruses use sea ice as a resting platform between dives to forage for clams and other bottom-dwelling invertebrates. How have sea ice changes affected polar bears and walruses? How will anticipated changes affect them in the future?
García, Désirée; Vassena, Rita; Prat, Andrés; Vernaeve, Valérie
Reproduction is a matter of concern for individuals and society due to the postponement of childbearing, and healthcare professionals are the main source of information and counselling. This study aims to evaluate how knowledgeable healthcare professionals are about fertility and assisted reproduction, and to explore attitudes towards social oocyte freezing. A cross-sectional study was performed with 201 professionals (gynaecologists, physicians and nurses) from four public centres in Spain. Participants completed a survey about fertility, IVF, oocyte donation (OD) and social oocyte freezing, between May 2013 and March 2014. Reported mean age limits for pregnancy were 39.5 ± 4.5 (spontaneously), 43.7 ± 5.2 (IVF) and 49.0 ± 6.5 (OD). Gynaecologists reported a younger limit for spontaneous and IVF pregnancies (P 39, compared with 77.3% of other physicians and 72.9% of nurses. Regarding social oocyte freezing, 41.8% of gynaecologists thought it should be offered to every young woman, versus 62.7% of other physicians and 48.9% of nurses (P = 0.041). In conclusion, gynaecologists are more knowledgeable about fertility and assisted reproduction, while more restrictive towards social oocyte freezing. Knowledge and attitudes could influence the quality of information and counselling given to patients. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Stefanelli, María de Los Ángeles; Valenzuela, María Teresa; Cárcamo, Marcela; Urquidi, Cinthya; Cavada, Gabriel; San Martín P, Pamela
The global fertility rate (GFR) is defined as the mean number of children that a woman could have in a hypothetical cohort, not exposed to death during the fertile period. GFR has fallen from 3.4 to 1.9 children per women in the period 1970-2010. To explore the relationship between the fall in GFR and the incorporation of women to work in the period 1960-2011. Data from the National Statistics Institute was used. GRF was calculated using specific fertility rates for each year considering women aged 15 to 49 years. Work rates were obtained from yearly vital statistics reports. Between 1960 and 2011, GRF decreased from 5.5 to 1.9 in Chile. The first inflection occurred in 1970. In the same period, female workforce increased from 22.4 to 40.2%. To motivate the participation of female work-force without decrease the GRF allowing population replacement, it is suggested the need to create new public policies with benefits and support from the state.
Andersen, Thomas B.; Dalgaard, Carl-Johan Lars; Selaya, Pablo
This research advances and empirically establishes the hypothesis that regional variation in the historical incidence of eye disease has influenced the current global distribution of per capita income. By reducing work life expectancy, high historical eye disease incidence has served to diminish...... the incentive to accumulate skills, thereby delaying the fertility transition and the take-off to sustained economic growth. As a consequence of a differential timing of the take-off to growth, prompted by differences in the inherent return to skill formation, global income disparities have emerged....
Full Text Available The P wave parameters measured by 12-lead electrocardiogram (ECG are commonly used as noninvasive tools to assess for left atrial enlargement. There are limited studies to evaluate whether P wave parameters are independently associated with decline in renal function. Accordingly, the aim of this study is to assess whether P wave parameters are independently associated with progression to renal end point of ≥25% decline in estimated glomerular filtration rate (eGFR. This longitudinal study included 166 patients. The renal end point was defined as ≥25% decline in eGFR. We measured two ECG P wave parameters corrected by heart rate, i.e. corrected P wave dispersion (PWdisperC and corrected P wave maximum duration (PWdurMaxC. Heart function and structure were measured from echocardiography. Clinical data, P wave parameters, and echocardiographic measurements were compared and analyzed. Forty-three patients (25.9% reached renal end point. Kaplan-Meier curves for renal end point-free survival showed PWdisperC > median (63.0 ms (log-rank P = 0.004 and PWdurMaxC > median (117.9 ms (log-rank P<0.001 were associated with progression to renal end point. Multivariate forward Cox-regression analysis identified increased PWdisperC (hazard ratio [HR], 1.024; P = 0.001 and PWdurMaxC (HR, 1.029; P = 0.001 were independently associated with progression to renal end point. Our results demonstrate that increased PWdisperC and PWdurMaxC were independently associated with progression to renal end point. Screening patients by means of PWdisperC and PWdurMaxC on 12 lead ECG may help identify a high risk group of rapid renal function decline.
Cerveri, Isa; Corsico, Angelo G; Grosso, Amelia; Albicini, Federica; Ronzoni, Vanessa; Tripon, Bianca; Imberti, Federica; Galasso, Thomas; Klersy, Catherine; Luisetti, Maurizio; Pistolesi, Massimo
Early identification of patients with COPD and prone to more rapid decline in lung function is of particular interest from both a prognostic and therapeutic point of view. The aim of this study was to identify the clinical, functional and imaging characteristics associated with the rapid FEV(1) decline in COPD. Between 2001 and 2005, 131 outpatients with moderate COPD in stable condition under maximum inhaled therapy underwent clinical interview, pulmonary function tests and HRCT imaging of the chest and were followed for at least 3 years. Twenty-six percent of patients had emphysema detected visually using HRCT. The FEV(1) decline was 42 ± 66 mL/y in the total sample, 88 ± 76 mL/y among rapid decliners and 6 ± 54 mL/y among the other patients. In the univariable analysis, the decline of FEV(1) was positively associated with pack-years (p emphysema at HRCT (p emphysema proved to be an independent prognostic factor of rapid decline (p = 0.001). When emphysema was replaced by RV, the model still remained significant. The rapid decline in lung function may be identified by the presence of emphysema at HRCT or increased RV in patients with a long smoking history.
Glaser, Karen; Agree, Emily M; Costenbader, Elizabeth; Camargo, Antonio; Trench, Belkis; Natividad, Josefina; Chuang, Yi-Li
To compare family structures and support for older persons in two Asian countries (Taiwan and the Philippines) and six urban areas in Latin America (Buenos Aires, São Paulo, Havana, Santiago, Mexico City, and Montevideo). Using the 1999 Survey of Health and Living Status of the Elderly in Taiwan, the 2000 Philippine Survey of the Near Elderly and Elderly, and the 2001 Pan American Health Organisation surveys on Salud, Bienestar y Envejecimiento en América Latina y el Caribe, descriptive tables show variations across countries in family structure, proximity, and transfers of support by the timing of the fertility transition in each location. Older people in settings with earlier transitions had fewer children and more childlessness, higher levels of solitary living, and lower levels of co-residence with children. In earlier transition settings, receipt of family support was lower and provision higher. The timing of the demographic transition has significant implications for kin availability and support.
Piotrowski, Martin; Tong, Yuying
We examine the effect of education on birth outcomes in China during the period of economic transition and large-scale changes in mass education and population control measures. Retrospective micro data from the 2008 Chinese General Social Survey and discrete time event history analysis are used to examine the fertility history of several cohorts of women born between 1945 and 1968. We observed births at different parities, distinguishing the education effect across cohorts and rural/urban sectors. We found differences across cohorts consistent with unique features of the Chinese context, such as the radical egalitarian era of educational expansion, and the Reform Era. We also found that despite the increase in some education levels across cohorts (e.g., junior high school in rural areas), birth chances were more likely to be concentrated among less educated women, suggesting the impact of factors related to returns to education and hence the desire for children. Copyright © 2015 Elsevier Inc. All rights reserved.
Moultrie, Tom A; Sayi, Takudzwa S; Timæus, Ian M
We investigated birth-interval dynamics in 24 African countries using data from 76 Demographic and Health Surveys conducted since 1986. Controlling for selection bias in the birth-history data using the Brass-Juárez method and regression models produced almost identical results. Birth intervals have lengthened in every country examined. This analysis uncovered a distinctive and previously undocumented pattern of childbearing that is prevalent across sub-Saharan Africa. After allowing for time trends in birth-interval length, the lengthening of birth intervals in almost every country varies little by women's age or parity. Moreover, in several countries, birth intervals are now too long to be explicable by birth spacing contingent on the age of women's youngest child. Rather, women are postponing births for other reasons. These findings offer empirical support for the idea that the fertility transition in sub-Saharan Africa is following a different pattern from that observed elsewhere.
This article explores the persistence of son preference in a patrilineal, patrilocal society in the midst of fertility decline. Using survey and ethnographic data from Hindu-caste Nepali families in a semiurban village, I analyze which cultural norms regarding reproduction are questioned by contemporary married couples and which remain intact. Despite modest improvements in gender equality, levels of education, and economic conditions, the practical knowledge that daughters will be lost to other lineages and households pressures couples who might otherwise be willing to invest in daughters to continue procreating until they produce a son. Young mothers, therefore, reluctantly admit to needing a son, revealing a discrepancy between their initially stated reproductive ideals and their ultimate behavior.
Amo-Adjei, Joshua; Mutua, Michael; Athero, Sherine; Izugbara, Chimaraoke; Ezeh, Alex
In this paper, we reflect on our experiences of implementing a multipronged intervention to improve sexual and reproductive health outcomes. The project used family planning as its entry point and was implemented in two high fertility counties-Busia and Siaya in Kenya. The intervention, implemented by a seven-member consortium, involved: family planning services delivery; regular training of service providers to deliver high quality services; monitoring and evaluation; strengthening of commodity chain delivery and forecasting; school-based and out-of-school based sexuality education; and advocacy and stakeholder engagements at the community, county and national levels. Over a 5-year period, the project contributed to raising demand for family planning considerably, evidenced in fertility decline. It also improved the capacity of family planning services providers, increased commitment and awareness of county government and other community stakeholders on the importance of investments in family planning. Our collaborations with organisations interested in sexual and reproductive health issues substantially enhanced the consortium's ability to increase demand for, and supply of family planning commodities. These collaborations are proving useful in the continuity and sustainability of project achievements.
Robert A Robinson
Full Text Available Emerging infectious diseases are increasingly cited as threats to wildlife, livestock and humans alike. They can threaten geographically isolated or critically endangered wildlife populations; however, relatively few studies have clearly demonstrated the extent to which emerging diseases can impact populations of common wildlife species. Here, we report the impact of an emerging protozoal disease on British populations of greenfinch Carduelis chloris and chaffinch Fringilla coelebs, two of the most common birds in Britain. Morphological and molecular analyses showed this to be due to Trichomonas gallinae. Trichomonosis emerged as a novel fatal disease of finches in Britain in 2005 and rapidly became epidemic within greenfinch, and to a lesser extent chaffinch, populations in 2006. By 2007, breeding populations of greenfinches and chaffinches in the geographic region of highest disease incidence had decreased by 35% and 21% respectively, representing mortality in excess of half a million birds. In contrast, declines were less pronounced or absent in these species in regions where the disease was found in intermediate or low incidence. Also, populations of dunnock Prunella modularis, which similarly feeds in gardens, but in which T. gallinae was rarely recorded, did not decline. This is the first trichomonosis epidemic reported in the scientific literature to negatively impact populations of free-ranging non-columbiform species, and such levels of mortality and decline due to an emerging infectious disease are unprecedented in British wild bird populations. This disease emergence event demonstrates the potential for a protozoan parasite to jump avian host taxonomic groups with dramatic effect over a short time period.
Toms, Mike P.; Peck, Kirsi M.; Kirkwood, James K.; Chantrey, Julian; Clatworthy, Innes R.; Evans, Andy D.; Hughes, Laura A.; Hutchinson, Oliver C.; John, Shinto K.; Pennycott, Tom W.; Perkins, Matthew W.; Rowley, Peter S.; Simpson, Vic R.; Tyler, Kevin M.; Cunningham, Andrew A.
Emerging infectious diseases are increasingly cited as threats to wildlife, livestock and humans alike. They can threaten geographically isolated or critically endangered wildlife populations; however, relatively few studies have clearly demonstrated the extent to which emerging diseases can impact populations of common wildlife species. Here, we report the impact of an emerging protozoal disease on British populations of greenfinch Carduelis chloris and chaffinch Fringilla coelebs, two of the most common birds in Britain. Morphological and molecular analyses showed this to be due to Trichomonas gallinae. Trichomonosis emerged as a novel fatal disease of finches in Britain in 2005 and rapidly became epidemic within greenfinch, and to a lesser extent chaffinch, populations in 2006. By 2007, breeding populations of greenfinches and chaffinches in the geographic region of highest disease incidence had decreased by 35% and 21% respectively, representing mortality in excess of half a million birds. In contrast, declines were less pronounced or absent in these species in regions where the disease was found in intermediate or low incidence. Also, populations of dunnock Prunella modularis, which similarly feeds in gardens, but in which T. gallinae was rarely recorded, did not decline. This is the first trichomonosis epidemic reported in the scientific literature to negatively impact populations of free-ranging non-columbiform species, and such levels of mortality and decline due to an emerging infectious disease are unprecedented in British wild bird populations. This disease emergence event demonstrates the potential for a protozoan parasite to jump avian host taxonomic groups with dramatic effect over a short time period. PMID:20805869
Wing, Maria R.; Devaney, Joseph M.; Joffe, Marshall M.; Xie, Dawei; Feldman, Harold I.; Dominic, Elizabeth A.; Guzman, Nicolas J.; Ramezani, Ali; Susztak, Katalin; Herman, James G.; Cope, Leslie; Harmon, Brennan; Kwabi-Addo, Bernard; Gordish-Dressman, Heather; Go, Alan S.; He, Jiang; Lash, James P.; Kusek, John W.; Raj, Dominic S.
Background Epigenetic mechanisms may be important in the progression of chronic kidney disease (CKD). Methods We studied the genome-wide DNA methylation pattern associated with rapid loss of kidney function using the Infinium HumanMethylation 450 K BeadChip in 40 Chronic Renal Insufficiency (CRIC) study participants (n = 3939) with the highest and lowest rates of decline in estimated glomerular filtration rate. Results The mean eGFR slope was 2.2 (1.4) and −5.1 (1.2) mL/min/1.73 m2 in the stable kidney function group and the rapid progression group, respectively. CpG islands in NPHP4, IQSEC1 and TCF3 were hypermethylated to a larger extent in subjects with stable kidney function (P-values of 7.8E−05 to 9.5E−05). These genes are involved in pathways known to promote the epithelial to mesenchymal transition and renal fibrosis. Other CKD-related genes that were differentially methylated are NOS3, NFKBIL2, CLU, NFKBIB, TGFB3 and TGFBI, which are involved in oxidative stress and inflammatory pathways (P-values of 4.5E−03 to 0.046). Pathway analysis using Ingenuity Pathway Analysis showed that gene networks related to cell signaling, carbohydrate metabolism and human behavior are epigenetically regulated in CKD. Conclusions Epigenetic modifications may be important in determining the rate of loss of kidney function in patients with established CKD. PMID:24516231
Full Text Available Aim: To determine predictive factors associated with rapid cognitive decline (RCD in elderly patients suffering from Alzheimer disease (AD. Methods: Patients suffering from mild to moderate AD were included. RCD was defined as the loss of at least 3 points on the Mini-Mental State Examination (MMSE over 12 months. Factors associated with RCD were identified by logistic regression. Results: Among 123 patients included, 61 were followed up until 12 months. RCD occurred in 46% of patients (n = 28. Polymedication (p < 0.0001, the fact that the caregiver was the child or spouse of the patient (p < 0.0001 and autonomy for washing (p < 0.0001 were protective factors against RCD, while the presence of caregiver burden (p < 0.0001 was shown to be a risk factor for RCD. Conclusion: Early detection of the RCD risk in AD patients could make it possible to anticipate the patient’s medical needs and adjust the care plan for caregiver burden.
Full Text Available Following the swift demise of the state-socialist regime in 1989, a profound transformation of family and fertility patterns has taken place in the Czech Republic. Family formation has been postponed and period fertility rates have fallen to very low levels, especially among young adults. Unmarried cohabitation has become relatively widespread and marriages have been progressively delayed or even foregone. These rapid shifts in family-related behaviour were primarily driven by a period change and resulted in a sharp discontinuity in cohort patterns of union formation and childbearing. We argue that the rapid change in family-related behaviour after 1990 was driven by a fundamental shift in the constraints and incentives for childbearing, which was conducive to later and more carefully planned family formation. The rapidity of observed changes can be explained as the outcome of a simultaneous occurrence of several factors, especially the expansion of higher education, the emergence of new opportunities competing with family life, increasing job competition, rising economic uncertainty in young adulthood, and changing partnership behaviour.
Katz, Ronit; Dalrymple, Lorien; de Boer, Ian; DeFilippi, Christopher; Kestenbaum, Bryan; Park, Meyeon; Sarnak, Mark; Seliger, Stephen; Shlipak, Michael
Background and objectives Elevations in N-terminal pro–B-type natriuretic peptide and high-sensitivity troponin T are associated with poor cardiovascular outcomes. Whether elevations in these cardiac biomarkers are associated with decline in kidney function was evaluated. Design, setting, participants, & measurements N-terminal pro–B-type natriuretic peptide and troponin T were measured at baseline in 3752 participants free of heart failure in the Cardiovascular Health Study. eGFR was determined from the Chronic Kidney Disease Epidemiology Collaboration equation using serum cystatin C. Rapid decline in kidney function was defined as decline in serum cystatin C eGFR≥30%, and incident CKD was defined as the onset of serum cystatin C eGFRkidney function decline adjusting for demographics, baseline serum cystatin C eGFR, diabetes, and other CKD risk factors. Results In total, 503 participants had rapid decline in serum cystatin C eGFR over a mean follow-up time of 6.41 (1.81) years, and 685 participants developed incident CKD over a mean follow-up time of 6.41 (1.74) years. Participants in the highest quartile of N-terminal pro–B-type natriuretic peptide (>237 pg/ml) had an 67% higher risk of rapid decline and 38% higher adjusted risk of incident CKD compared with participants in the lowest quartile (adjusted hazard ratio for serum cystatin C eGFR rapid decline, 1.67; 95% confidence interval, 1.25 to 2.23; hazard ratio for incident CKD, 1.38; 95% confidence interval, 1.08 to 1.76). Participants in the highest category of troponin T (>10.58 pg/ml) had 80% greater risk of rapid decline compared with participants in the lowest category (adjusted hazard ratio, 1.80; 95% confidence interval, 1.35 to 2.40). The association of troponin T with incident CKD was not statistically significant (hazard ratio, 1.17; 95% confidence interval, 0.92 to 1.50). Conclusions Elevated N-terminal pro–B-type natriuretic peptide and troponin T are associated with rapid decline of
Dribe, Martin; Hacker, J. David; Scalone, Francesco
Most previous work on the historical fertility transition has been macro-oriented, using aggregate data to examine economic correlates of demographic behaviour at regional or national levels, while much less has been done using micro data, and specifically looking at behavioural differentials among social groups. In this paper we study at the impact of socioeconomic status on net fertility during the fertility transition in five Northern American and European Countries (Canada, Iceland, Norway, Sweden and the USA). We use micro-level census data in 1900, containing information on number of children by age, occupation of the mother and father, place of residence and household context. The results show highly similar patterns across countries, with the elite and upper middle classes having considerably lower net fertility early in the transition. These patterns remain also after controlling for a range of individual and community-level fertility determinants and geographical unobserved heterogeneity. PMID:24684711
Thomas, Len; Jaramillo-Legorreta, Armando; Cardenas-Hinojosa, Gustavo; Nieto-Garcia, Edwyna; Rojas-Bracho, Lorenzo; Ver Hoef, Jay M; Moore, Jeffrey; Taylor, Barbara; Barlow, Jay; Tregenza, Nicholas
The vaquita is a critically endangered species of porpoise. It produces echolocation clicks, making it a good candidate for passive acoustic monitoring. A systematic grid of sensors has been deployed for 3 months annually since 2011; results from 2016 are reported here. Statistical models (to compensate for non-uniform data loss) show an overall decline in the acoustic detection rate between 2015 and 2016 of 49% (95% credible interval 82% decline to 8% increase), and total decline between 2011 and 2016 of over 90%. Assuming the acoustic detection rate is proportional to population size, approximately 30 vaquita (95% credible interval 8-96) remained in November 2016.
"The author attempts to expose and explain important elements of the demographic transition in the Austro-Hungarian Monarchy in the last third of the nineteenth century. This is done on the basis of regional differences and time differences of the Coale-Indices (Index of marital fertility, Index of proportion married and Index of overall fertility)." The author considers the differences between marital fertility in rural Hungary and in industrial Austria at the beginning of the demographic transition (SUMMARY IN ENG) excerpt
Conclusion: Serum uric acid level was associated with eGFR and decline in renal function in elderly Taiwanese subjects. Whether hypouricemic therapy could retard the progression of CKD deserves further in-depth study.
Dyah Anantalia Widyastari
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.
Yasir H. Ahmed-Braimah
Full Text Available The virilis group of Drosophila represents a relatively unexplored but potentially useful model to investigate the genetics of speciation. Good resolution of phylogenetic relationships and the ability to obtain fertile hybrid offspring make the group especially promising for analysis of genetic changes underlying reproductive isolation separate from hybrid sterility and inviability. Phylogenetic analyses reveal a close relationship between the sister species, Drosophila americana and D. novamexicana, yet excepting their contemporary allopatric distributions, factors that contribute to reproductive isolation between this species pair remain uncharacterized. A previous report has shown reduced progeny numbers in laboratory crosses between the two species, especially when female D. novamexicana are crossed with male D. americana. We show that the hatch rate of eggs produced from heterospecific matings is reduced relative to conspecific matings. Failure of eggs to hatch, and consequent reduction in hybrid progeny number, is caused by low fertilization success of heterospecific sperm, thus representing a postmating, prezygotic incompatibility. Following insemination, storage and motility of heterospecific sperm is visibly compromised in female D. novamexicana. Our results provide evidence for a mechanism of reproductive isolation that is seldom reported for Drosophila species, and indicate the rapid evolution of postmating, prezygotic reproductive barriers in allopatry.
Michael R. Haines; Avery M. Guest
.... Manuscripts from the New York State census of 1865 indicate a very slow decline in marital fertility during the initial decades of the nineteenth century and more rapid decline as the Civil War approached...
Jiang, Yang; Ju, Meiting; Li, Weizun; Ren, Qingbin; Liu, Le; Chen, Yu; Yang, Qian; Hou, Qidong; Liu, Yiliang
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.
Stavros D Veresoglou
Full Text Available Gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS was used to measure the (13C/(12C ratios of PLFAs at natural abundance levels from a temperate grassland nitrogen (N and phosphorus (P factorial fertilization experiment in northern Greece. In each plot two rhizosphere samples were derived centred around individual Agrostis capillaris and Prunella vulgaris plants. It was hypothesized that the isotopic signal of microbes that preferentially feed on recalcitrant litter such as fungi would be modified by fertilization more strongly than that of opportunistic microbes using labile C. Microbial community δ(13C was affected by both P and N fertilization regime and plant species identity. However, we have been unable to detect significant nutrient effects on individual groups of microbes when analyzed separately in contrast to our original hypothesis. Intra-treatment variability, as evaluated from Hartley's F(max tests in the five first PCA components axes as well as the size of the convex hulls in PCA scoreplots and Mahalanobis distances, was considerably higher in the non-fertilized controls. Moreover, a significant relationship was established between the change in PLFA abundances and their respective changes in δ(13C for the aggregate of samples and those simultaneously fertilized with N and P. We conclude that use of compound specific isotope analysis in the absence of labelling represents a valuable and overlooked tool in obtaining an insight of microbial community functioning.
Ozmeral, Erol J; Eddins, Ann C; Frisina, D Robert; Eddins, David A
The auditory system relies on extraordinarily precise timing cues for the accurate perception of speech, music, and object identification. Epidemiological research has documented the age-related progressive decline in hearing sensitivity that is known to be a major health concern for the elderly. Although smaller investigations indicate that auditory temporal processing also declines with age, such measures have not been included in larger studies. Temporal gap detection thresholds (TGDTs; an index of auditory temporal resolution) measured in 1071 listeners (aged 18-98 years) were shown to decline at a minimum rate of 1.05 ms (15%) per decade. Age was a significant predictor of TGDT when controlling for audibility (partial correlation) and when restricting analyses to persons with normal-hearing sensitivity (n = 434). The TGDTs were significantly better for males (3.5 ms; 51%) than females when averaged across the life span. These results highlight the need for indices of temporal processing in diagnostics, as treatment targets, and as factors in models of aging. Copyright © 2016 Elsevier Inc. All rights reserved.
Lenk, Janine; Engellandt, Kay; Terai, Naim; Bottesi, Antonia; Matthé, Egbert
Heidenhain variant of Creutzfeldt-Jakob (HvCJD) is a rare disease, patients presenting with loss of visual acuity and a decline in visual fields. Two patients with rapid loss of visual acuity and declining visual fields presented with homonymic hemianopsia over several weeks. Cranial MRI showed neither stroke nor other morphological changes explaining the severe visual field defects. Neurological examination revealed no pathologies. However, lumbar puncture showed an increase in total protein in cerebrospinal fluid (CSF). Visual field testing revealed further deterioration during follow-up. Several weeks later, patients' behaviour changed markedly, exhibiting aggression, declining memory function and physical degeneration. The suspected diagnosis was the Heidenhain variant of Creutzfeld-Jakob disease (HvCJD). CSF analysis showed evidence of PrP Sc and 14-3-3 protein. Both patients died within 8 weeks of the CJD diagnosis. Loss of visual acuity and a decline in visual fields without corresponding MRI findings and marked changes in behaviour should lead to a diagnosis of HvCJD. Corresponding diagnostic tests should be performed for confirmation. The prognosis for survival is poor and should be immediately communicated to affected patients and their relatives. Copyright © 2018 Elsevier Ltd. All rights reserved.
This research attempts to compare the issue of school integration between Japan and Korea, both of whose fertility is now declining rapidly. In Japan, the tendency of fertility decline appears earlier than in Korea, and in Korea, the decline of fertility was appeared in 1980s. And, in proportion to the decline of fertility, the number of school integration is increased in both Japan and Korea. However, the way of school integration and policies related to it are very different between Japan a...
Full Text Available ObjectivesREM sleep behavior disorder (RBD is associated with cognitive dysfunctions and is a risk factor for development of mild cognitive impairment and dementia. However, it is unknown whether RBD is associated with faster cognitive decline in already established dementia. The main goal of this study was to determine if patients with mild dementia with and without RBD differ in progression rate and in specific neuropsychological measures over 4-year follow-up.MethodsThis longitudinal, prospective study based on data from the DemVest study compares neuropsychological measures in a mild dementia cohort. A diagnosis of probable RBD (pRBD was made based on the Mayo Sleep Questionnaire. Neuropsychological domains were assessed by Mini Mental State Examination, total score and figure copying, California Verbal Learning Test-II, Visual Object and Space Perception Cube and Silhouettes, Boston Naming Test, Stroop test, Verbal Category Fluency, Trail Making Test A and B.ResultsAmong the 246 subjects, 47 (19.1% had pRBD at the baseline, and pRBD group was younger and with male predominance. During 4-year follow-up, we did not observe any significant differences in the rate of decline in neuropsychological measures. Patients with pRBD performed generally poorer in visuoconstructional, visuoperceptual, and executive/attention tests in comparison to RBD negative.ConclusionWe did not find any significant differences in progression rate of neurocognitive outcomes between dementia patients with and without RBD.
Epps, CW; Palsboll, PJ; Wehausen, JD; Roderick, GK; Ramey, RR; McCullough, DR
The rapid expansion of road networks has reduced connectivity among populations of flora and fauna. The resulting isolation is assumed to increase population extinction rates, in part because of the loss of genetic diversity. However, there are few cases where loss of genetic diversity has been
Newton, Matilda S; Arcus, Vickery L; Patrick, Wayne M
The evolution of enzymes is often viewed as following a smooth and steady trajectory, from barely functional primordial catalysts to the highly active and specific enzymes that we observe today. In this review, we summarize experimental data that suggest a different reality. Modern examples, such as the emergence of enzymes that hydrolyse human-made pesticides, demonstrate that evolution can be extraordinarily rapid. Experiments to infer and resurrect ancient sequences suggest that some of the first organisms present on the Earth are likely to have possessed highly active enzymes. Reconciling these observations, we argue that rapid bursts of strong selection for increased catalytic efficiency are interspersed with much longer periods in which the catalytic power of an enzyme erodes, through neutral drift and selection for other properties such as cellular energy efficiency or regulation. Thus, many enzymes may have already passed their catalytic peaks. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Vernon, Daniel M.; Ostrem, James A.; Schmitt, Juergen M.; Bohnert, Hans J.
Mesembryanthemum crystallinum plants respond to water stress by changing their pathway of carbon assimilation from C3 to Crassulacean acid metabolism (CAM). Stressed plants are characterized by elevated levels of phosphoenolpyruvate carboxylase (PEPCase) mRNA, protein, and enzyme activity. We wanted to determine whether CAM is a reversible response to environmental conditions or a developmentally programmed adaptation that is irreversibly expressed once induced. Plants were osmotically stressed by irrigation with 500 millimolar NaCl for 12 days to elicit CAM. Salt was then thoroughly flushed from the soil and PEPCase protein and transcript levels were monitored. PEPCase mRNA levels dropped by 77% within 2.5 hours after salt removal. PEPCase activity and polypeptide levels declined more slowly, with a half-life of 2 to 3 days. These results show that PEPCase expression in M. crystallinum is a reversible response to stress that is regulated at the level of transcription or stability of the PEPCase mRNA. Images Fig. 2 Fig. 3 PMID:16666021
Levin, David C; Parker, Laurence; Palit, Charles D; Rao, Vijay M
Imaging is an important cost driver in health care, and its use grew rapidly in the early 2000s. Several studies toward the end of the decade suggested that a leveling off was beginning to occur. In this study we examined more recent data to determine whether the slowdown had continued. Our data sources were the nationwide Medicare Part B databases for the period 2001-14. We calculated utilization rates per 1,000 enrollees for all advanced imaging modalities. We also calculated professional component relative value unit (RVU) rates per 1,000 beneficiaries for all imaging modalities, as RVU values provide a measure of complexity of imaging services and may in some ways be a better reflection of the amount of work involved in imaging. We found that utilization rates and RVU rates grew substantially until 2008 and 2009, respectively, and then began to drop. The downward trend in both rates persisted through 2014. Federal policies appear to have achieved the desired effect of ending the rapid growth of imaging that had been seen in earlier years. Project HOPE—The People-to-People Health Foundation, Inc.
Hossack, Blake R; Lowe, Winsor H; Corn, Paul Stephen
Climate change is expected to increase the frequency and severity of drought and wildfire. Aquatic and moisture-sensitive species, such as amphibians, may be particularly vulnerable to these modified disturbance regimes because large wildfires often occur during extended droughts and thus may compound environmental threats. However, understanding of the effects of wildfires on amphibians in forests with long fire-return intervals is limited. Numerous stand-replacing wildfires have occurred since 1988 in Glacier National Park (Montana, U.S.A.), where we have conducted long-term monitoring of amphibians. We measured responses of 3 amphibian species to fires of different sizes, severity, and age in a small geographic area with uniform management. We used data from wetlands associated with 6 wildfires that burned between 1988 and 2003 to evaluate whether burn extent and severity and interactions between wildfire and wetland isolation affected the distribution of breeding populations. We measured responses with models that accounted for imperfect detection to estimate occupancy during prefire (0-4 years) and different postfire recovery periods. For the long-toed salamander (Ambystoma macrodactylum) and Columbia spotted frog (Rana luteiventris), occupancy was not affected for 6 years after wildfire. But 7-21 years after wildfire, occupancy for both species decreased ≥ 25% in areas where >50% of the forest within 500 m of wetlands burned. In contrast, occupancy of the boreal toad (Anaxyrus boreas) tripled in the 3 years after low-elevation forests burned. This increase in occupancy was followed by a gradual decline. Our results show that accounting for magnitude of change and time lags is critical to understanding population dynamics of amphibians after large disturbances. Our results also inform understanding of the potential threat of increases in wildfire frequency or severity to amphibians in the region. ©2012 Society for Conservation Biology.
Hossack, Blake R.; Lowe, Winsor H.; Corn, Paul Stephen
Climate change is expected to increase the frequency and severity of drought and wildfire. Aquatic and moisture-sensitive species, such as amphibians, may be particularly vulnerable to these modified disturbance regimes because large wildfires often occur during extended droughts and thus may compound environmental threats. However, understanding of the effects of wildfires on amphibians in forests with long fire-return intervals is limited. Numerous stand-replacing wildfires have occurred since 1988 in Glacier National Park (Montana, U.S.A.), where we have conducted long-term monitoring of amphibians. We measured responses of 3 amphibian species to fires of different sizes, severity, and age in a small geographic area with uniform management. We used data from wetlands associated with 6 wildfires that burned between 1988 and 2003 to evaluate whether burn extent and severity and interactions between wildfire and wetland isolation affected the distribution of breeding populations. We measured responses with models that accounted for imperfect detection to estimate occupancy during prefire (0-4 years) and different postfire recovery periods. For the long-toed salamander (Ambystoma macrodactylum) and Columbia spotted frog (Rana luteiventris), occupancy was not affected for 6 years after wildfire. But 7-21 years after wildfire, occupancy for both species decreased ≥ 25% in areas where >50% of the forest within 500 m of wetlands burned. In contrast, occupancy of the boreal toad (Anaxyrus boreas) tripled in the 3 years after low-elevation forests burned. This increase in occupancy was followed by a gradual decline. Our results show that accounting for magnitude of change and time lags is critical to understanding population dynamics of amphibians after large disturbances. Our results also inform understanding of the potential threat of increases in wildfire frequency or severity to amphibians in the region.
Rovero, Francesco; Mtui, Arafat; Kitegile, Amani; Jacob, Philipo; Araldi, Alessandro; Tenan, Simone
Growing threats to primates in tropical forests make robust and long-term population abundance assessments increasingly important for conservation. Concomitantly, monitoring becomes particularly relevant in countries with primate habitat. Yet monitoring schemes in these countries often suffer from logistic constraints and/or poor rigor in data collection, and a lack of consideration of sources of bias in analysis. To address the need for feasible monitoring schemes and flexible analytical tools for robust trend estimates, we analyzed data collected by local technicians on abundance of three species of arboreal monkey in the Udzungwa Mountains of Tanzania (two Colobus species and one Cercopithecus), an area of international importance for primate endemism and conservation. We counted primate social groups along eight line transects in two forest blocks in the area, one protected and one unprotected, over a span of 11 years. We applied a recently proposed open metapopulation model to estimate abundance trends while controlling for confounding effects of observer, site, and season. Primate populations were stable in the protected forest, while the colobines, including the endemic Udzungwa red colobus, declined severely in the unprotected forest. Targeted hunting pressure at this second site is the most plausible explanation for the trend observed. The unexplained variability in detection probability among transects was greater than the variability due to observers, indicating consistency in data collection among observers. There were no significant differences in both primate abundance and detectability between wet and dry seasons, supporting the choice of sampling during the dry season only based on minimizing practical constraints. Results show that simple monitoring routines implemented by trained local technicians can effectively detect changes in primate populations in tropical countries. The hierarchical Bayesian model formulation adopted provides a flexible
Dozier, André Q.; Arabi, Mazdak; Wostoupal, Benjamin C.; Goemans, Christopher G.; Zhang, Yao; Paustian, Keith
In rapidly urbanizing semi-arid regions, increasing amounts of historically irrigated cropland lies permanently fallowed due to water court policies as agricultural water rights are voluntarily being sold to growing cities. This study develops an integrative framework for assessing the effects of population growth and land use change on agricultural production and evaluating viability of alternative management strategies, including alternative agricultural transfer methods, regional water ownership restrictions, and urban conservation. A partial equilibrium model of a spatially-diverse regional water rights market is built in application of the framework to an exemplary basin. The model represents agricultural producers as profit-maximizing suppliers and municipalities as cost-minimizing consumers of water rights. Results indicate that selling an agricultural water right today is worth up to two times more than 40 years of continued production. All alternative policies that sustain agricultural cropland and crop production decrease total agricultural profitability by diminishing water rights sales revenue, but in doing so, they also decrease municipal water acquisition costs. Defining good indicators and incorporating adequate spatial and temporal detail are critical to properly analyzing policy impacts. To best improve agricultural profit from production and sale of crops, short-term solutions include alternative agricultural transfer methods while long-term solutions incorporate urban conservation.
Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to subreplacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman - not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change - that is, periods of economic growth are conducive to fertility increase whereas bad economic times are associated with reduced fertility.
Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to sub-replacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman---not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change --- that is, periods of economic growth are conducive to fertility increase whereas bad economic times lead to reduced fertility.
Araeva, Nyudlia; Nevalyonnaya, Anna; Buchanan, David
The article compares an analysis of Russian federal policy documents enacted to address the decline in population size (apparent since the collapse of the former Soviet Union), with interviews of women living in two provincial capitals, Pskov and Velikiye Novgorod. The analysis indicates that the values reflected in state policy documents regarding the definition of the problem, the stated goals of family policy and the methods designated to achieve those goals are not consistent with the views and understandings of women representative of those targeted by state family policy, on the nature of the problem, the goals that they think most important to achieve, and the most effective means to accomplish them. Policies to promote greater gender equality and to provide quality secondary education are perceived to be essential pre-conditions to reverse population declines.
Southern leaf blight disease severity is correlated with decreased maize leaf epiphytic bacterial species richness and the phyllosphere bacterial diversity decline is enhanced by nitrogen fertilization.
Manching, Heather C; Balint-Kurti, Peter J; Stapleton, Ann E
Plant leaves are inhabited by a diverse group of microorganisms that are important contributors to optimal growth. Biotic and abiotic effects on plant growth are usually studied in controlled settings examining response to variation in single factors and in field settings with large numbers of variables. Multi-factor experiments with combinations of stresses bridge this gap, increasing our understanding of the genotype-environment-phenotype functional map for the host plant and the affiliated epiphytic community. The maize inbred B73 was exposed to single and combination abiotic and the biotic stress treatments: low nitrogen fertilizer and high levels of infection with southern leaf blight (causal agent Cochliobolus heterostrophus). Microbial epiphyte samples were collected at the vegetative early-season phase and species composition was determined using 16S ribosomal intergenic spacer analysis. Plant traits and level of southern leaf blight disease were measured late-season. Bacterial diversity was different among stress treatment groups (P species richness-alpha diversity-was correlated with increased severity of southern leaf blight disease when disease pressure was high. Nitrogen fertilization intensified the decline in bacterial alpha diversity. While no single bacterial ribotype was consistently associated with disease severity, small sets of ribotypes were good predictors of disease levels. Difference in leaf bacterial-epiphyte diversity early in the season were correlated with plant disease severity, supporting further tests of microbial epiphyte-disease correlations for use in predicting disease progression.
Southern leaf blight disease severity is correlated with decreased maize leaf epiphytic bacterial species richness and the phyllosphere bacterial diversity decline is enhanced by nitrogen fertilization
Full Text Available Plant leaves are inhabited by a diverse group of microorganisms that are important contributors to optimal growth. Biotic and abiotic effects on plant growth are usually studied in controlled settings examining response to variation in single factors and in field settings with large numbers of variables. Multi-factor experiments with combinations of stresses bridge this gap, increasing our understanding of the genotype-environment-phenotype functional map for the host plant and the affiliated epiphytic community. The maize inbred B73 was exposed to single and combination abiotic and the biotic stress treatments: low nitrogen fertilizer and high levels of infection with southern leaf blight (causal agent Cochliobolus heterostrophus. Microbial epiphyte samples were collected at the vegetative early-season phase and species composition was determined using 16S ribosomal intergenic spacer analysis. Plant traits and level of southern leaf blight disease were measured late-season. Bacterial diversity was different among stress treatment groups (P< 0.001. Lower species richness—alpha diversity--was correlated with increased severity of southern leaf blight disease when disease pressure was high. Nitrogen fertilization intensified the decline in bacterial alpha diversity. While no single bacterial ribotype was consistently associated with disease severity, small sets of ribotypes were good predictors of disease levels. Difference in leaf bacterial-epiphyte diversity early in the season were correlated with plant disease severity, supporting further tests of microbial epiphyte-disease correlations for use in predicting disease progression.
Zavala De Cosio, M E
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
Yeh, Jason S; Steward, Ryan G; Dude, Annie M; Shah, Anish A; Goldfarb, James M; Muasher, Suheil J
To use a large and recent national registry to provide an updated report on the effect of recipient age on the outcome of donor oocyte in vitro fertilization (IVF) cycles. Retrospective cohort study. United States national registry for assisted reproductive technology. Recipients of donor oocyte treatment cycles between 2008 and 2010, with cycles segregated into five age cohorts: ≤34, 35 to 39, 40 to 44, 45 to 49, and ≥50 years. None. Implantation, clinical pregnancy, live-birth, and miscarriage rates. In donor oocyte IVF cycles, all age cohorts ≤39 years had similar rates of implantation, clinical pregnancy, and live birth when compared with the 40- to 44-year-old reference group. Patients in the two oldest age groups (45 to 49, ≥50 years) experienced statistically significantly lower rates of implantation, clinical pregnancy, and live birth compared with the reference group. Additionally, all outcomes in the ≥50-year-old group were statistically significantly worse than the 45- to 49-year-old group, demonstrating progressive decline with advancing age. Recent national registry data suggest that donor oocyte recipients have stable rates of pregnancy outcomes before age 45, after which there is a small but steady and significant decline. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Jansson, E; Ruokonen, M; Kojola, I; Aspi, J
The grey wolves (Canis lupus) of Finland have had a varied history, with a period of rapid population expansion after the mid-1990s followed by a decline with a current census size of about 140 wolves. Here, we investigate the impact of unstable population size and connectivity on genetic diversity and structure in a long-term genetic study of 298 Finnish wolves born in 1995-2009 and genotyped for 17 microsatellite loci. During the initial recovery and prior to population expansion, genetic diversity was high (1995-1997: LD-N(e) = 67.2; H(o) = 0.749; H(e) = 0.709) despite a small census size and low number of breeders (N(c) < 100; N(b) < 10) likely reflecting the status of the Russian source population. Surprisingly, observed heterozygosity decreased significantly during the study period (t = -2.643, P = 0.021) despite population expansion, likely a result of an increase in inbreeding (F(IS) = 0.108 in 2007-2009) owing to a low degree of connectivity with adjacent Russian wolf population (m = 0.016-0.090; F(ST) = 0.086, P < 0.001) and population crash after 2006. However, population growth had a temporary positive impact on N(e) and number of family lines. This study shows that even strong population growth alone might not be adequate to retain genetic diversity, especially when accompanied with low amount of subsequent gene flow and population decline. © 2012 Blackwell Publishing Ltd.
Bai, Yanchao; Zang, Caiyun; Gu, Minjing; Gu, Chuanhui; Shao, Hongbo; Guan, Yongxiang; Wang, Xukui; Zhou, Xiaojian; Shan, Yuhua; Feng, Ke
Sewage sludge is by-product in the process of centralized wastewater treatment. Land application of sewage sludge is one of the important disposal alternatives. Mudflats in the interaction zone between land and sea can be important alternative sources for arable lands if amended by large amount of organic fertilizers. Rich in organic matter and other nutrients, sewage sludge has been considered as the economic choice for an initial fertility driver. However, sewage sludge amendment has been greatly hampered due to availability of potential toxic metals. Using sewage sludge in compliance with the national standards for agricultural usage could avoid the accumulation of heavy metals. Nevertheless, it is not clear whether massive input of sewage sludge would increase heavy metals concentration in crops. The objective of this study was to investigate impact of sewage sludge amendment (SSA) as an initial fertility driver by one-time input, with the rates of 0, 30, 75, 150, and 300tha -1 , on biomass of green manures, soil chemical properties, and growth and heavy metals uptake of maize (Zea mays L.) grown in mudflat soil. Results showed that one-time sewage sludge amendment promoted an initial fertility for infertile mudflat soil, supported growth of ryegrass as the first season green manure. By tilled ryegrass, it modified the chemical properties of mudflat soil by increasing soil organic carbon, total and available N and P, and decreasing soil salinity and pH, which promoted subsequent growth of two green manures for sesbania and ryegrass. The sewage sludge as an initial fertility driver combined with planting and tilling green manures, increased dry matter of the aerial part and grain yield of maize grown in mudflat soil. Cd and Ni concentrations in grain of maize were positively correlated with sewage sludge amendment rates. Importantly, heavy metal concentrations in grain of maize at all SSA rates did not exceed the safety standard for food in China (GB 2762
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
Full Text Available Background. Predicting the progression of kidney failure in patients with chronic kidney disease is difficult. The aim of this study was to assess the predictors of rapid kidney decline in a cohort of patients referred to a single outpatient nephrology clinic. Design. Longitudinal, prospective cohort study with a median follow-up of 3.39 years. Methods. Data were obtained from 306 patients with chronic renal failure based on serum creatinine-estimated glomerular filtration rate (eGFRcreat 4 mL/min/1.73 m2. We recorded nonfatal cardiovascular events at baseline and during follow-up in addition to biochemical parameters. Results. The mean loss in renal function was 1.22 mL/min/1.73 m2 per year. The mean age was 75 ± 8.8 years old, and the mean baseline eGFRcreat was 42 ± 14 mL/min/1.73 m2. Almost one-fourth of the sample (23.3% [63 patients] suffered a rapid decline in renal function. In a logistic regression model with rapid decline as the outcome, baseline characteristics, lower serum albumin (OR: 0.313, 95% CI: 0.114–0.859, previous cardiovascular disease (OR: 1.903 95% CI: 1.028–3.523, and higher proteinuria (g/24 h (OR: 1.817 CI 95%: 1.213–2.723 were the main predictors of rapid kidney decline. On multivariate analysis, including baseline and follow-up data, we obtained similar adjusted associations of rapid kidney decline with baseline serum albumin and proteinuria. The follow-up time was also shorter in the group with rapid rates of decline in renal function. Conclusion. Renal function remained stable in the majority of our population. Previous cardiovascular disease and cardiovascular incidents, lower serum albumin, and higher proteinuria at baseline were the main predictors of rapid kidney decline in our population.
Dart, S; Eckert, C G
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.
Haines, Michael R; Guest, Avery M
Knowledge is quite limited about the extent and social correlates of marital fertility decline for the United States in the early part of the nineteenth century. Manuscripts from the New York State census of 1865 indicate a very slow decline in marital fertility during the initial decades of the nineteenth century and more rapid decline as the Civil War approached. Little evidence of fertility control within marriage is found for the very oldest women in the sample, but analysis of parity progression ratios indicates that some control had emerged by the midpoint of the nineteenth century. Fertility decline was most evident in the urban, more economically developed areas, but our data also indicate that the limited availability of agricultural land may have affected the transition. While a marital fertility transition occurred in nineteenth-century New York, many couples in various geographic areas and social strata continued to have quite high levels of fertility, indicating difficulties that were probably faced in controlling reproduction.
Reed, Sasha C.; Coe, Kirsten K.; Sparks, Jed P.; Housman, David C.; Zelikova, Tamara J.; Belnap, Jayne
Arid and semi-arid ecosystems cover ~40% of Earth’s terrestrial surface, but we know little about how climate change will affect these widespread landscapes. Like many drylands, the Colorado Plateau in southwestern United States is predicted to experience elevated temperatures and alterations to the timing and amount of annual precipitation. We used a factorial warming and supplemental rainfall experiment on the Colorado Plateau to show that altered precipitation resulted in pronounced mortality of the widespread moss Syntrichia caninervis. Increased frequency of 1.2 mm summer rainfall events reduced moss cover from ~25% of total surface cover to fertility. Mosses are important members in many dryland ecosystems and the community changes observed here reveal how subtle modifications to climate can affect ecosystem structure and function on unexpectedly short timescales. Moreover, mortality resulted from increased precipitation through smaller, more frequent events, underscoring the importance of precipitation event size and timing, and highlighting our inadequate understanding of relationships between climate and ecosystem function in drylands.
Enrico Spolaore; Romain Wacziarg
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...
Hu, Susie L; Joshi, Priyanka; Kaplan, Mark; Lefkovitz, Judy; Poenariu, Andreea; Dworkin, Lance D; Michaud, Dominique S
The survival advantage observed among peritoneal dialysis patients early on after dialysis initiation has been largely attributed to residual renal function (RRF) preservation due to higher baseline residual function and fewer comorbidities. We hypothesize that a rapid decline in RRF is associated with higher risk of anuria and mortality. In a retrospective cohort study of 581 subjects on peritoneal dialysis with longitudinal prevalent data, we assessed whether RRF change over time, in addition to baseline RRF, increased risk of mortality and anuria using Kaplan-Meier analysis and Cox proportional hazard analysis to control for known risk factors. Rapid RRF decline (≥ 0.09 decline) over a 12-month period was associated with a 2.6-fold increase in the risk of death (hazard ratio [HR] 2.60, 95% confidence interval [CI] 1.66 - 4.07, compared with anuria (HR 2.06, 95% CI 1.24 - 3.42). Each quartile of increasing severity of RRF decline over a 12-month period increased risk incrementally for death (2 nd quartile: HR 3.04, CI 1.26 - 7.34; 3 rd quartile: HR 4.01, CI 1.71 - 9.83; 4 th quartile HR 5.78, CI 2.10 - 15.9) and generally for anuria (quartiles with HR 5.72 - 7.21). The escalating risk of mortality and anuria was greater for those with diabetes mellitus. In conclusion, rapid decline in RRF over a 12-month period increased the risk of mortality and likewise anuria, beyond previously established risk factors for mortality and anuria. The impact on mortality and RRF preservation was particularly severe for those with diabetes mellitus. Copyright © 2017 International Society for Peritoneal Dialysis.
Suzuki, Masaru; Makita, Hironi; Östling, Jörgen
COPD cohort study (P = 0.003, P = 0.004, respectively). A lower plasma leptin/adiponectin ratio was also significantly associated with an annual decline in FEV1 in subjects with airflow limitation in the CBQ study (P = 0.014), the patients of which had largely different clinical characteristics...... compared with the Hokkaido COPD cohort study. There were no significant associations between lung function decline and adipokine levels in subjects without airflow limitation. CONCLUSIONS: A lower leptin/adiponectin ratio was associated with lung function decline in patients with COPD in two independent......RATIONALE: The rate of annual change in FEV1 is highly variable among patients with chronic obstructive pulmonary disease (COPD). Reliable blood biomarkers are needed to predict prognosis. OBJECTIVES: To explore plasma biomarkers associated with an annual change in FEV1 in patients with COPD...
April E. Nuckolls; Nina Wurzburger; Chelcy R. Ford; Ronald L. Hendrick; James M. Vose; Brian D. Kloeppel
The recent infestation of southern Appalachian eastern hemlock stands by hemlock woolly adelgid (HWA) is expected to have dramatic and lasting effects on forest structure and function. We studied the short-term changes to the carbon cycle in a mixed stand of hemlock and hardwoods, where hemlock was declining due to either girdling or HWA infestation. We expected that...
Suzuki, Masaru; Makita, Hironi; Östling, Jörgen; Thomsen, Laura H; Konno, Satoshi; Nagai, Katsura; Shimizu, Kaoruko; Pedersen, Jesper H; Ashraf, Haseem; Bruijnzeel, Piet L B; Maciewicz, Rose A; Nishimura, Masaharu
The rate of annual change in FEV1 is highly variable among patients with chronic obstructive pulmonary disease (COPD). Reliable blood biomarkers are needed to predict prognosis. To explore plasma biomarkers associated with an annual change in FEV1 in patients with COPD. Plasma samples of 261 subjects, all Japanese, with COPD from the 5-year Hokkaido COPD cohort study were analyzed as a hypothesis-generating cohort, and the results were validated using data of 226 subjects with and 268 subjects without airflow limitation, mainly white, from the 4-year COPD Quantification by Computed Tomography, Biomarkers, and Quality of Life (CBQ) study conducted in Denmark. The plasma samples were measured using Human CardiovascularMAP (Myriad RBM, Austin, TX), which could analyze 50 biomarkers potentially linked with inflammatory, metabolic, and tissue remodeling pathways, and single ELISAs were used to confirm the results. Higher plasma adiponectin levels and a lower leptin/adiponectin ratio at enrollment were significantly associated with an annual decline in FEV1 even after controlling for age, sex, height, and body mass index in the Hokkaido COPD cohort study (P = 0.003, P = 0.004, respectively). A lower plasma leptin/adiponectin ratio was also significantly associated with an annual decline in FEV1 in subjects with airflow limitation in the CBQ study (P = 0.014), the patients of which had largely different clinical characteristics compared with the Hokkaido COPD cohort study. There were no significant associations between lung function decline and adipokine levels in subjects without airflow limitation. A lower leptin/adiponectin ratio was associated with lung function decline in patients with COPD in two independent Japanese and Western cohort studies of populations of different ethnicity. Measure of systemic adipokines may provide utility in predicting patients with COPD at higher risk of lung function decline.
Hornum, M.; Iversen, M.; Steffensen, I.
renal failure within 2 weeks post-LTx (p = 0.0003), use of heart and lung machine (p = 0.04), and the use of ephedrine (p = 0.048), as well as increasing age, older than 18 years at LTx (p = 0.006). These data demonstrate that renal function, measured with an isotope method, decreases dramatically......We previously described a 54% decline in renal function at 6 months after lung transplantation (LTx). We hypothesized that this decline is a very early event following LTx. Thirty-one consecutive patients (16 females/15 males), mean age 49 (+/-13) years, with emphysema, cystic fibrosis....../bronchiectasis or idiopathic pulmonary fibrosis were included in an analysis of renal function before and after LTx. The glomerular filtration rate (GFR) was measured using the (51)Cr-ethylenediaminetetra acetic acid plasma clearance single injection technique (mGFR) at baseline before transplantation and at 1, 2, 3 and 12...
Full Text Available The aim of this study was to estimate the development of fertility in North-Central Namibia, former Ovamboland, from 1960 to 2001. Special attention was given to the onset of fertility decline and to the impact of the HIV epidemic on fertility. An additional aim was to introduce parish registers as a source of data for fertility research in Africa. Data used consisted of parish registers from Evangelical Lutheran congregations, the 1991 and 2001 Population and Housing Censuses, the 1992 and 2000 Namibia Demographic and Health Surveys, and the HIV sentinel surveillances of 1992-2004. Both period and cohort fertility were analysed. The P/F ratio method was used when analysing census data. The impact of HIV infection on fertility was estimated indirectly by comparing the fertility histories of women who died at an age of less than 50 years with the fertility of other women. The impact of the HIV epidemic on fertility was assessed both among infected women and in the general population. Fertility in the study population began to decline in 1980. The decline was rapid during the 1980s, levelled off in the early 1990s at the end of war of independence and then continued to decline until the end of the study period. According to parish registers, total fertility was 6.4 in the 1960s and 6.5 in the 1970s, and declined to 5.1 in the 1980s and 4.2 in the 1990s. Adjustment of these total fertility rates to correspond to levels of fertility based on data from the 1991 and 2001 censuses resulted in total fertility declining from 7.6 in 1960-79 to 6.0 in 1980-89, and to 4.9 in 1990-99. The decline was associated with increased age at first marriage, declining marital fertility and increasing premarital fertility. Fertility among adolescents increased, whereas the fertility of women in all other age groups declined. During the 1980s, the war of independence contributed to declining fertility through spousal separation and delayed marriages. Contraception
Kitai, Yuichiro; Doi, Yohei; Osaki, Keisuke; Sugioka, Sayaka; Koshikawa, Masao; Sugawara, Akira
Proteinuria is an established risk factor for progression of renal disease, including diabetic nephropathy. The predictive power of proteinuria, especially nephrotic range proteinuria, for progressive renal deterioration has been well demonstrated in diabetic patients with normal to relatively preserved renal function. However, little is known about the relationship between severity of proteinuria and renal outcome in pre-dialysis diabetic patients with severely impaired renal function. 125 incident dialysis patients with type 2 diabetes were identified. This study was aimed at retrospectively evaluating the impact of nephrotic range proteinuria (urinary protein-creatinine ratio above 3.5 g/gCr) on renal function decline during the 3 months just prior to dialysis initiation. In total, 103 patients (82.4 %) had nephrotic range proteinuria. The median rate of decline in estimated glomerular filtration rate (eGFR) in this study population was 0.98 (interquartile range 0.51-1.46) ml/min/1.73 m(2) per month. Compared to patients without nephrotic range proteinuria, patients with nephrotic range proteinuria showed significantly faster renal function decline (0.46 [0.24-1.25] versus 1.07 [0.64-1.54] ml/min/1.73 m(2) per month; p = 0.007). After adjusting for gender, age, systolic blood pressure, serum albumin, calcium-phosphorus product, hemoglobin A1c, and use of an angiotensin-converting enzyme inhibitor or an angiotensin II receptor blocker, patients with nephrotic range proteinuria showed a 3.89-fold (95 % CI 1.08-14.5) increased risk for rapid renal function decline defined as a decline in eGFR ≥0.5 ml/min/1.73 m(2) per month. Nephrotic range proteinuria is the predominant renal risk factor in type 2 diabetic patients with severely impaired renal function receiving pre-dialysis care.
A. Malcolm Gill
Full Text Available The Adelaide-Mt Lofty Region of South Australia is an exemplar, in microcosm, of the issues confronting biodiversity conservation in a world of increasing population and a drying, fire-prone environment. At just 0.1% of Australia’s terrestrial land mass, this area is largely peninsular and oriented along a spine of ranges to 730-m elevation. Annual average rainfall varies from over 1100 mm in the hills to less than 500 mm on the plains in the north. The original vegetation varied from grasslands to shrublands to grassy and shrubby woodlands to forests, but now includes a major capital city and a mixed farming hinterland. Biodiversity in the region is in decline, and many species’ extinctions have been recorded. With increasing population and a drying climate, fire antecedents, like ignition and fire danger, are predicted to increase the area burned in the wetter regions, but such predictions may be offset by increasing the fire protection of the expanding population and their economic and social assets. While the existing system of many small reserves will remain the backbone of biodiversity conservation in the region, wider recognition of the all-tenure, whole-of-landscape, whole-of-community approach to biodiversity conservation and fire management is needed if the probability of further extinctions is to be reduced.
Violi, Francesco; Pastori, Daniele; Perticone, Francesco; Hiatt, William R; Sciacqua, Angela; Basili, Stefania; Proietti, Marco; Corazza, Gino R; Lip, Gregory Y H; Pignatelli, Pasquale
Objective To investigate the relationship between Ankle-Brachial Index (ABI) and renal function progression in patients with atrial fibrillation (AF). Design Observational prospective multicentre cohort study. Setting Atherothrombosis Center of I Clinica Medica of ‘Sapienza’ University of Rome; Department of Medical and Surgical Sciences of University Magna Græcia of Catanzaro; Atrial Fibrillation Registry for Ankle-Brachial Index Prevalence Assessment-Collaborative Italian Study. Participants 897 AF patients on treatment with vitamin K antagonists. Main outcome measures The relationship between basal ABI and renal function progression, assessed by the estimated Glomerular Filtration Rate (eGFR) calculated with the CKD-EPI formula at baseline and after 2 years of follow-up. The rapid decline in eGFR, defined as a decline in eGFR >5 mL/min/1.73 m2/year, and incident eGFR60 mL/min/1.73 m2, 153 (23.9%) had a reduction of the eGFR <60 mL/min/1.73 m2. ABI ≤0.90 was also an independent predictor for incident eGFR<60 mL/min/1.73 m2 (HR 1.851, 95% CI 1.205 to 2.845, p=0.005). Conclusions In patients with AF, an ABI ≤0.90 is independently associated with a rapid decline in renal function and incident eGFR<60 mL/min/1.73 m2. ABI measurement may help identify patients with AF at risk of renal function deterioration. Trial registration number NCT01161251. PMID:25998039
Latham, Michael C., Ed.
The three papers in this collection discuss, respectively, the relationship of breastfeeding to human fertility, strategies to improve feeding of infants and young children, and infant feeding options for Thai professional women residing in Bangkok. Specific topics addressed in the first paper include the physiological role of lactation on…
Noble, J; Potts, M
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.
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.
Kevin T. Smith
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...
Giardina, Bennett J; Stein, Kathryn; Chiang, Hui-Ling
Protein secretion is a fundamental process in all living cells. Gluconeogenic enzymes are secreted when Saccharomyces cerevisiae are grown in media containing low glucose. However, when cells are transferred to media containing high glucose, they are internalized. We investigated whether or not gluconeogenic enzymes were associated with extracellular vesicles in glucose-starved cells. We also examined the role that the endocytosis gene END3 plays in the internalization of extracellular proteins/vesicles in response to glucose addition. Transmission electron microscopy was performed to determine the presence of extracellular vesicles in glucose-starved wild-type cells and the dynamics of vesicle transport in cells lacking the END3 gene. Proteomics was used to identify extracellular proteins that associated with these vesicles. Total extracts prepared from glucose-starved cells consisted of about 95% small vesicles (30-50 nm) and 5% large structures (100-300 nm). The addition of glucose caused a rapid decline in small extracellular vesicles in wild-type cells. However, most of the extracellular vesicles were still observed in cells lacking the END3 gene following glucose replenishment. Proteomics was used to identify 72 extracellular proteins that may be associated with these vesicles. Gluconeogenic enzymes fructose-1,6-bisphosphatase, malate dehydrogenase, isocitrate lyase, and phosphoenolpyruvate carboxykinase, as well as non-gluconeogenic enzymes glyceraldehyde-3-phosphate dehydrogenase and cyclophilin A, were distributed in the vesicle-enriched fraction in total extracts prepared from cells grown in low glucose. Distribution of these proteins in the vesicle-enriched fraction required the integrity of the membranes. When glucose was added to glucose-starved wild-type cells, levels of extracellular fructose-1,6-bisphosphatase, malate dehydrogenase, isocitrate lyase, phosphoenolpyruvate carboxykinase, glyceraldehyde-3-phosphate dehydrogenase, and cyclophilin A were
National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...
Full Text Available Abstract Background Non-nucleoside reverse transcriptase inhibitor (NNRTI with stavudine and lamivudine is widely used as the first-line antiretroviral therapy (ART in resource-limited settings. Lipodystrophy is common and options for switching ART regimen are limited; this situation can lead to patients' poor adherence and antiretroviral resistance. Treatment interruption (TI in patients with high CD4 cell counts, lipodystrophy, and limited options may be an alternative in resource-limited settings. This study aimed to determine time to resume ART after TI and predictors for early resumption of ART in a resource-limited setting. Methods A prospective study was conducted in January 2005 to December 2006 and enrolled HIV-infected patients with HIV-1 RNA 350 cells/mm3, and willing to interrupt ART. CD4 cell count, HIV-1 RNA, lipid profile, and lipodystrophy were assessed at baseline and every 3 months. ART was resumed when CD4 declined to 3 or developed HIV-related symptoms. Patients were grouped based on ART regimens [NNRTI or protease inhibitor (PI] prior to TI. Results There were 99 patients, 85 in NNRTI group and 14 in PI group. Mean age was 40.6 years; 46% were males. Median duration of ART was 47 months. Median nadir CD4 and baseline CD4 were 151 and 535 cells/mm3, respectively. Median CD4 change at 3 months after TI were -259 (NNRTI and -105 (PI cells/mm3 (p = 0.038. At 13-month median follow-up, there was no AIDS-defining illness; 38% (NNRTI and 29% (PI of patients developed HIV-related symptoms. ART was resumed in 51% (NNRTI and 36% (PI of patients (p = 0.022. By Kaplan-Meier analysis, median time to resume ART was 5.5 (NNRTI and 14.2 (PI months (log rank test, p = 0.026. By Cox's regression analysis, NNRTI-based ART (HR 4.9; 95%CI, 1.5–16.3, nadir CD4 3 (HR 2.7; 95%CI 1.4–5.3 and baseline CD4 3 (HR 1.6; 95%CI, 1.2–3.1 were predictors for early ART resumption. Conclusion TI of NNRTI-based ART leads to rapid CD4 decline and high
Schaible, R.; Scheuerlein, A.; Danko, M. J.
Senescence, the increase in mortality and decline in fertility with age after maturity, was thought to be inevitable for all multicellular species capable of repeated breeding. Recent theoretical advances and compilations of data suggest that mortality and fertility trajectories can go up or down...... that 2,256 Hydra from two closely related species in two laboratories in 12 cohorts, with cohort age ranging from 0 to more than 41 y, have extremely low, constant rates of mortality. Fertility rates for Hydra did not systematically decline with advancing age. This falsifies the universality...... expectancy of Hydra in the wild. A high proportion of stem cells, constant and rapid cell turnover, few cell types, a simple body plan, and the fact that the germ line is not segregated from the soma are characteristics of Hydra that may make nonsenescence feasible. Nonsenescence may be optimal because...
Liu, Jian-Jun; Pek, Sharon Li Ting; Ang, Kevin; Tavintharan, Subramaniam; Lim, Su Chi
Abnormal angiogenesis plays an important role in pathogenesis of diabetic kidney disease (DKD). Leucine-rich α-2 glycoprotein 1 (LRG1) is a newly identified angiogenic factor. To study whether plasma LRG1 may independently predict progression of DKD in individuals with type 2 diabetes mellitus (T2DM). Prospective cohort study in a regional hospital. In total, 1226 T2DM participants were followed for a mean ± standard deviation (SD) of 3.1 ± 0.4 years. Albuminuria progression was defined as elevation in albuminuria level to a higher category. Chronic kidney disease (CKD) progression [rapid estimated glomerular filtration rate (eGFR) decline] was defined as a 40% or greater deterioration in eGFR in 3 years. Both participants with albuminuria progression and those with CKD progression had higher plasma LRG1 levels at baseline. LRG1 independently predicted albuminuria progression above traditional risk factors, including baseline eGFR and urine albumin to creatinine ratio. A 1-SD increment in LRG1 was associated with a 1.26-fold [95% confidence interval (CI), 1.04 to 1.53, P = 0.018] higher adjusted risk for albuminuria progression. The association of LRG1 with microalbuminuria to macroalbuminuria progression was stronger than its association with normoalbuminuria to microalbuminuria progression [odds ratio (OR), 1.51; 95% CI, 1.04 to 2.18, P = 0.029 vs OR, 1.09; 95% CI, 0.86 to 1.37, P = 0.486, per 1-SD LRG1 increment]. Also, LRG1 independently predicted CKD progression above traditional risk factors. A 1-SD increment in LRG1 was associated with a 1.48-fold (95% CI, 1.04 to 2.11, P = 0.032) higher adjusted risk for CKD progression. Plasma LRG1 predicts both albuminuria and CKD progression beyond traditional risk factors. It may play a role in the pathologic pathway leading to progression of DKD in T2DM.
Pierik, M.; Van Ruijven, J.; Bezemer, T.M.; Geerts, R.H.E.M.; Berendse, F.
Nutrient enrichment of habitats (eutrophication) is considered to be one of the main causes of plant diversity decline worldwide. Several experiments have shown a rapid loss of species in the first years after fertilization started. However, little is known about changes in species richness in the
Han, J; Cho, L; Choe, M K; Tuan, C
Korean minority women in China have registered dramatic declines in fertility since 1950. The annual growth rate of the Chinese population averaged 2.1% in the 1964-82 period and that for the Han majority was 2.0%. The growth rates for all other ethnic groups were higher than the national average, except for the Korean minority (1.5%). Between the mid-1960s and mid-1970s the fertility decline was particularly marked among Yanbian Korean women; the total fertility rate dropped from 4.8 in 1965 to 1.9 in 1975. With small fluctuations, fertility has remained at or slightly below replacement level since 1975. The observation that Yanbian Koreans began and completed the fertility transition earlier than the rest of China is puzzling given the fact that government family planning programs have less stringent requirements for minorities. Since 1975, the childbearing of Korean women in China has been virtually limited to ages 20-29 years and there are relatively small differences in fertility for women with different levels of education. It is speculated that the migrant Koreans are a selected group of people who place less value on traditional norms and thus are more receptive to the small family size ideal. The fact that this minority has its own language schools and mass communication systems has meant that new norms adopted by the elite are spread to the rest of the Korean population at a pace faster than that in typical Chinese communities. When China introduced its ambitious national family planning program in the 1970s, the Koreans who had already begun the fertility transition were given the means to complete it at a very rapid pace. Overall, the fertility transition of Yanbian Korean women shows that rapid economic progress is not essential to a rapid decline in fertility if other conditions are favorable.
Kanté, Almamy M; Nathan, Rose; Helleringer, Stéphane; Sigilbert, Mrema; Levira, Francis; Masanja, Honorati; de Savigny, Don; Abdulla, Salim; Phillips, James F
Under-five mortality has been declining rapidly in a number of sub-Saharan African settings. Malaria-related mortality is known to be a major component of childhood causes of death and malaria remains a major focus of health interventions. The paper explored the contribution of malaria relative to other specific causes of under-five deaths to these trends. This paper uses longitudinal demographic surveillance data to examine trends and causes of death of under-five mortality in Rufiji, whose population has been followed for over nine years (1999-2007). Causes of death, determined by the verbal autopsy technique, are analysed with Arriaga's decomposition method to assess the contribution of declining malaria-related mortality relative to other causes of death as explaining a rapid decline in overall childhood mortality. Over the 1999-2007 period, under-five mortality rate in Rufiji declined by 54.3%, from 33.3 to 15.2 per 1,000 person-years. If this trend is sustained, Rufiji will be a locality that achieves MDG4 target. Although hypotrophy at birth remained the leading cause of death for neonates, malaria remains as the leading cause of death for post-neonates followed by pneumonia. However, declines in malaria death rates accounted for 49.9% of the observed under-five mortality decline while all perinatal causes accounted for only 19.9%. To achieve MDG 4 in malaria endemic settings, health programmes should continue efforts to reduce malaria mortality and more efforts are also needed to improve newborn survival.
HAINES, MICHAEL R.; GUEST, AVERY M.
Knowledge is quite limited about the extent and social correlates of marital fertility decline for the United States in the early part of the nineteenth century. Manuscripts from the New York State census of 1865 indicate a very slow decline in marital fertility during the initial decades of the nineteenth century and more rapid decline as the Civil War approached. Little evidence of fertility control within marriage is found for the very oldest women in the sample, but analysis of parity progression ratios indicates that some control had emerged by the midpoint of the nineteenth century. Fertility decline was most evident in the urban, more economically developed areas, but our data also indicate that the limited availability of agricultural land may have affected the transition. While a marital fertility transition occurred in nineteenth-century New York, many couples in various geographic areas and social strata continued to have quite high levels of fertility, indicating difficulties that were probably faced in controlling reproduction. PMID:18613485
Full Text Available Oak decline is generally accepted to be the result of a dynamic interaction between oaks and a mix of abiotic and biotic causes, within which environmental stresses (drought, salinity, frost, low fertility may be important as predisposing factors. As a result of these interactions, trees gradually begin to show symptoms of general suffering, which below ground consist of functional and anatomical modifications to the rootlets and changes in the ectomycorrhizal status. The present study was performed in a coastal Quercus ilex forest, where decline symptoms appeared after heavy land reclamation in the adjoining areas, which caused a rapid lowering of the ground water level and the underground intrusion of seawater from the neighbouring Adriatic Sea into the forest itself. A forest survey including examination of rootlet features from asymptomatic and declining trees suggested that drought and salinity were involved in this decline. The relative frequency of the most recurrent ectomycorrhizal morphotypes distinguished clearly between asymptomatic, weakly declining and strongly declining trees, suggesting that the occurrence and distribution of only a limited number of morphotypes can give an indication of the severity of the decline. Moreover, of all the morphotypes observed only one third were found in all three decline classes, while the remaining two thirds were gradually replaced by others as the proportion of declining trees increased, where the number of morphotypes was greater. The hypothesis of an adaptive response of the ectomycorrhizal community to decline or to the predisposing factors of decline is discussed.
Parrado, Emilio A; Morgan, S Philip
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.
Full Text Available Background: The Qinghai-Tibet Plateau (QTP is home to the vast grassland in China. The QTP grassland ecosystem has been seriously degraded by human land use practices and climate change. Fertilization is used in this region to increase vegetation yields for grazers. The impact of long-term fertilization on plant and microbial communities has been studied extensively. However, the influence of short-term fertilization on arbuscular mycorrhizal fungal (AMF communities in the QTP is largely unknown, despite their important functional role in grassland ecosystems. Methods: We investigated AMF community responses to three years of N and/or P addition at an experimental field site on the QTP, using the Illumina MiSeq platform (PE 300. Results: Fertilization resulted in a dramatic shift in AMF community composition and NP addition significantly increased AMF species richness and phylogenetic diversity. Aboveground biomass, available phosphorus, and NO3− were significantly correlated with changes in AMF community structure. Changes in these factors were driven by fertilization treatments. Thus, fertilization had a large impact on AMF communities, mediated by changes in aboveground productivity and soil chemistry. Discussion: Prior work has shown how plants often lower their reliance on AMF symbioses following fertilization, leading to decrease AMF abundance and diversity. However, our study reports a rise in AMF diversity with fertilization treatment. Because AMF can provide stress tolerance to their hosts, we suggest that extreme weather on the QTP may help drive a positive relationship between fertilizer amendment and AMF diversity.
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.
Kaptijn, Ralf; Thomese, Fleur; Liefbroer, Aart C
Several hypotheses have been put forward to explain the relationship between women's fertility and their post-reproductive longevity. In this study, we focus on the disposable soma theory, which posits that a negative relationship between women's fertility and longevity can be understood...... as an evolutionary trade-off between reproduction and survival. We examine the relationship between fertility and longevity during the epidemiological transition in the Netherlands. This period of rapid decline in mortality from infectious diseases offers a good opportunity to study the relationship between...... fertility and longevity, using registry data from 6,359 women born in The Netherlands between 1850 and 1910. We hypothesize that an initially negative relationship between women's fertility and their longevity gradually turns less negative during the epidemiological transition, because of decreasing costs...
Hendi, Arun S
The rise of the global network of nation-states has precipitated social transformations throughout the world. This article examines the role of political and economic globalization in driving fertility convergence across countries between 1965 and 2009. While past research has typically conceptualized fertility change as a country-level process, this study instead employs a theoretical and methodological framework that examines differences in fertility between pairs of countries over time. Convergence in fertility between pairs of countries is hypothesized to result from increased cross-country connectedness and cross-national transmission of fertility-related schemas. I investigate the impact of various cross-country ties, including ties through bilateral trade, intergovernmental organizations, and regional trade blocs, on fertility convergence. I find that globalization acts as a form of social interaction to produce fertility convergence. There is significant heterogeneity in the effects of different cross-country ties. In particular, trade with rich model countries, joint participation in the UN and UNESCO, and joining a free trade agreement all contribute to fertility convergence between countries. Whereas the prevailing focus in fertility research has been on factors producing fertility declines, this analysis highlights specific mechanisms-trade and connectedness through organizations-leading to greater similarity in fertility across countries. Globalization is a process that propels the spread of culturally laden goods and schemas impinging on fertility, which in turn produces fertility convergence.
Pathak, K B; Murty, P K
indicators, and in these countries the fertility declines were very low. Countries like Hong Kong, Korea, Malaysia, and Singapore had already crossed the threshold zones for almost all of the indicators, and there has been a rapid decline in fertility in these countries. Countries like Sri Lanka and the Philippines have entered the threshold zone only for some of the indicators and hence experienced only moderate fertility decline. As the data used for the analysis are of limited reliability, the findings should be taken only as tentative.
Sevel, L.; Nord-Larsen, Thomas; Ingerslev, Morten
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...
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.
Aquino, E G
increased by about 7.5% between 1953-72. The major increase occurred during the post war years. All of these occurred during the time period when the Philippines underwent major socioeconomic changes. Data on changes in socioeconomic indicators during the time period under observation were presented. For example, between 1948-70, the literacy rate increased from 62.8%-84.6% for males and from 56.9%-82.2% for females. The infant mortality rate declined from 125.5-67.3 between 1948-70, and breastfeeding declined from 64.2%-26.5% between 1958-74. The increase in the natural fertility level tapered off during the last few years, and in the future the impact of fertility control on the fertility rate should become stronger.
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.
Palmateer, Norah E; Taylor, Avril; Goldberg, David J; Munro, Alison; Aitken, Celia; Shepherd, Samantha J; McAllister, Georgina; Gunson, Rory; Hutchinson, Sharon J
Government policy has precipitated recent changes in the provision of harm reduction interventions - injecting equipment provision (IEP) and opiate substitution therapy (OST) - for people who inject drugs (PWID) in Scotland. We sought to examine the potential impact of these changes on hepatitis C virus (HCV) transmission among PWID. We used a framework to triangulate different types of evidence: 'group-level/ecological' and 'individual-level'. Evidence was primarily generated from bio-behavioural cross-sectional surveys of PWID, undertaken during 2008-2012. Individuals in the window period (1-2 months) where the virus is present, but antibodies have not yet been formed, were considered to have recent infection. The survey data were supplemented with service data on the provision of injecting equipment and OST. Ecological analyses examined changes in intervention provision, self-reported intervention uptake, self-reported risk behaviour and HCV incidence; individual-level analyses investigated relationships within the pooled survey data. Nearly 8,000 PWID were recruited in the surveys. We observed a decline in HCV incidence, per 100 person-years, from 13.6 (95% CI: 8.1-20.1) in 2008-09 to 7.3 (3.0-12.9) in 2011-12; a period during which increases in the coverage of OST and IEP, and decreases in the frequency of injecting and sharing of injecting equipment, were observed. Individual-level evidence demonstrated that combined high coverage of needles/syringes and OST were associated with reduced risk of recent HCV in analyses that were unweighted (AOR 0.29, 95%CI 0.11-0.74) and weighted for frequency of injecting (AORw 0.05, 95%CI 0.01-0.18). We estimate the combination of harm reduction interventions may have averted 1400 new HCV infections during 2008-2012. This is the first study to demonstrate that impressive reductions in HCV incidence can be achieved among PWID over a relatively short time period through high coverage of a combination of interventions.
Norah E Palmateer
Full Text Available BACKGROUND: Government policy has precipitated recent changes in the provision of harm reduction interventions - injecting equipment provision (IEP and opiate substitution therapy (OST - for people who inject drugs (PWID in Scotland. We sought to examine the potential impact of these changes on hepatitis C virus (HCV transmission among PWID. METHODS AND FINDINGS: We used a framework to triangulate different types of evidence: 'group-level/ecological' and 'individual-level'. Evidence was primarily generated from bio-behavioural cross-sectional surveys of PWID, undertaken during 2008-2012. Individuals in the window period (1-2 months where the virus is present, but antibodies have not yet been formed, were considered to have recent infection. The survey data were supplemented with service data on the provision of injecting equipment and OST. Ecological analyses examined changes in intervention provision, self-reported intervention uptake, self-reported risk behaviour and HCV incidence; individual-level analyses investigated relationships within the pooled survey data. Nearly 8,000 PWID were recruited in the surveys. We observed a decline in HCV incidence, per 100 person-years, from 13.6 (95% CI: 8.1-20.1 in 2008-09 to 7.3 (3.0-12.9 in 2011-12; a period during which increases in the coverage of OST and IEP, and decreases in the frequency of injecting and sharing of injecting equipment, were observed. Individual-level evidence demonstrated that combined high coverage of needles/syringes and OST were associated with reduced risk of recent HCV in analyses that were unweighted (AOR 0.29, 95%CI 0.11-0.74 and weighted for frequency of injecting (AORw 0.05, 95%CI 0.01-0.18. We estimate the combination of harm reduction interventions may have averted 1400 new HCV infections during 2008-2012. CONCLUSIONS: This is the first study to demonstrate that impressive reductions in HCV incidence can be achieved among PWID over a relatively short time period through
Kolk, Martin; Cownden, Daniel; Enquist, Magnus
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
... 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 ...
Mveyange, Anthony Francis
A consensus among social scientists is that fertility rates in Africa are declining. What determines these declines? I present fresh evidence that shows education, especially for women, is an important determinant of the fertility transition in Africa. This finding is consistent with the predicti......A consensus among social scientists is that fertility rates in Africa are declining. What determines these declines? I present fresh evidence that shows education, especially for women, is an important determinant of the fertility transition in Africa. This finding is consistent...... with the predictions of the unified growth theory and sheds important insights in explaining the sustained income growth Africa has experienced since 1995. The paper also shows that the effects of income per capita and child mortality on fertility rates are non-robust and inconsistent with the predictions...
Fertility trends and prospects for east and southeast Asian countries including cities in China, Taiwan, the Republic of Korea, Thailand, Indonesia, Malaysia, the Philippines, Myanmar, and Viet Nam are described. Additional discussion focuses on family planning methods, marriage patterns, fertility prospects, theories of fertility change, and policy implications for the labor supply, labor migrants, increased female participation in the labor force (LFP), human resource development, and social policy measures. Figures provide graphic descriptions of total fertility rates (TFRS) for 12 countries/areas for selected years between 1960-90, TFR for selected Chinese cities between 1955-90, the % of currently married women 15-44 years using contraception by main method for selected years and for 10 countries, actual and projected TFR and annual growth rates between 1990-2020 for Korea and Indonesia. It is noted that the 1st southeast Asian country to experience a revolution in reproductive behavior was Japan with below replacement level fertility by 1960. This was accomplished by massive postponement in age at marriage and rapid reduction in marital fertility. Fertility was controlled primarily through abortion. Thereafter every southeast Asian country experienced fertility declines. Hong Kong, Penang, Shanghai, Singapore, and Taipei and declining fertility before the major thrust of family planning (FP). Chinese fertility declines were reflected in the 1970s to the early 1980s and paralleled the longer, later, fewer campaign and policy which set ambitious targets which were strictly enforced at all levels of administration. Korea and Taiwan's declines were a result of individual decision making to restrict fertility which was encouraged by private and government programs to provide FP information and subsidized services. The context was social and economic change. Indonesia's almost replacement level fertility was achieved dramatically through the 1970s and 1980s by
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
Hanafiah, Hazlenah; Jemain, Abdul Aziz
In recent years, the study of fertility has been getting a lot of attention among research abroad following fear of deterioration of fertility led by the rapid economy development. Hence, this study examines the feasibility of developing fertility forecasts based on age structure. Lee Carter model (1992) is applied in this study as it is an established and widely used model in analysing demographic aspects. A singular value decomposition approach is incorporated with an ARIMA model to estimate age specific fertility rates in Peninsular Malaysia over the period 1958-2007. Residual plots is used to measure the goodness of fit of the model. Fertility index forecast using random walk drift is then utilised to predict the future age specific fertility. Results indicate that the proposed model provides a relatively good and reasonable data fitting. In addition, there is an apparent and continuous decline in age specific fertility curves in the next 10 years, particularly among mothers' in their early 20's and 40's. The study on the fertility is vital in order to maintain a balance between the population growth and the provision of facilities related resources.
Sneddon, Mark; Pearse, William D.
Species of plants and animals have populations that are declining at a rapid rate and possibly face extinction. To combat this decline, we must first understand where and why species are declining. We compared known species population growth rates in the COMPADRE (7024 different plant populations) and COMADRE (1927 different animal populations) databases to a variety of possible factors and other databases.
Michaela Potančoková; Boris Vano; Viera Pilinská; Danuša Jurčová
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...
Initial Nitrous Oxide Fluxes from a Maize-legume Cropping. System in a Soil of the Derived Savanna Zone ... Legume-maize crop rotations are used as a mechanism to reverse declining soil fertility in West. Africa. However, such crop rotations ... and nitrogen fertilizer replacement values et al., 2000). between 50 and 120 kg ...
De Jager, N. R.; Pastor, J.
Ungulate herbivores create patterns of forage availability, plant species composition, and soil fertility as they range across large landscapes and consume large quantities of plant material. Over time, herbivore populations fluctuate, producing great potential for spatio-temporal landscape dynamics. In this study, we extend the spatial and temporal extent of a long-term investigation of the relationship of landscape patterns to moose foraging behavior at Isle Royale National Park, MI. We examined how patterns of browse availability and consumption, plant basal area, and soil fertility changed during a recent decline in the moose population. We used geostatistics to examine changes in the nature of spatial patterns in two valleys over 18 years and across short-range and long-range distance scales. Landscape patterns of available and consumed browse changed from either repeated patches or randomly distributed patches in 1988-1992 to random point distributions by 2007 after a recent record high peak followed by a rapid decline in the moose population. Patterns of available and consumed browse became decoupled during the moose population low, which is in contrast to coupled patterns during the earlier high moose population. Distributions of plant basal area and soil nitrogen availability also switched from repeated patches to randomly distributed patches in one valley and to random point distributions in the other valley. Rapid declines in moose population density may release vegetation and soil fertility from browsing pressure and in turn create random landscape patterns. ?? Springer Science+Business Media B.V. 2009.
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.
David H. Alban; Richard F. Watt
Fertilization of poor site black spruce on organic soil with various rates of nitrogen and phosphorus increased height and diameter growth from 2 to 4 times. The growth response declined with time but was still apparent 16 years after fertilization. Shrub biomass and coverage, and nutrient levels of spruce foliage were strongly affected by fertilization.
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 ...
This study reviews and synthesizes the soil fertility status, management among smallholder farmers and research in the three countries of east Africa, namely Kenya, Tanzania and Uganda. We observe that many studies note the declining soil fertility, mainly due to soil fertility mining, putting crop production in an ...
Zelalem, Desalew; Semahegn, Agumasie; Tesfaye, Gezahegn; Sileshi, Balewgize
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.
Santelli, John S; Melnikas, Andrea J
After considerable declines in teen birth and pregnancy rates between 1991 and 2005, teen birth rates rose unexpectedly in 2006 and 2007. To understand these recent trends, we examined historical changes in fertility, trends in sexual behaviors, social forces, and public policies that may influence teen fertility. Although social forces such as poverty are critical in shaping adolescent reproductive choices, these do not explain rapid change in teen pregnancy risk since 1991. These recent changes, including increases in teen births since 2005, follow closely changes in teen contraceptive use. Likewise, contraceptive use is critical in explaining differences between U.S. and European fertility patterns. Public policies related to HIV prevention and sexuality education may have played a critical role in influencing teen pregnancy risk.
Full Text Available Women and men globally are delaying the birth of their first child. In the UK, the average age of first conception in women is 29 years. Women experience age-related fertility decline so it is important that men and women are well-informed about this, and other aspects of fertility. A group of UK stakeholders have established the Fertility Education Initiative to develop tools and information for children, adults, teachers, parents and healthcare professionals dedicated to improving knowledge of fertility and reproductive health.
Full Text Available For a very long time, Albania has had one of the highest levels of fertility in Europe: in 2002 the total fertility rate of 2.2 children per woman was the highest in Europe. Although this current level is high, the country has experienced a rapid fertility reduction during the last 50 years: a TFR decline from 7 to 2.2. This reduction has occurred in the absence of modern contraception and abortion, which indicates the significance of investments in the social agenda during the communist regime that produced policies with indirect effects on fertility. Most significant of these were policies focused on education, in particular on female education. Social and demographic settings for a further fertility reduction in Albania have been present since 1990. Contraception and abortion have been legalized and available since the early 1990s, but knowledge of their use is still not widespread in the country, largely due to the interplay between traditional and modern norms of Albanian society. This chapter points out that future fertility levels will be determined not only by new policies that might be introduced, but predominantly by the balance of this interplay.
Effect of phosphorus fertilizer application on some forms of phosphorus in ... The addition of organic litter alone had little effect on bicarbonate-extractable ... When litter and phosphorus fertilizer were added together, there was an initial rapid ...
Singh, K; Viegas, O; Ratnam, S S
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
Schaible, Ralf; Scheuerlein, Alexander; Dańko, Maciej J; Gampe, Jutta; Martínez, Daniel E; Vaupel, James W
Senescence, the increase in mortality and decline in fertility with age after maturity, was thought to be inevitable for all multicellular species capable of repeated breeding. Recent theoretical advances and compilations of data suggest that mortality and fertility trajectories can go up or down, or remain constant with age, but the data are scanty and problematic. Here, we present compelling evidence for constant age-specific death and reproduction rates in Hydra, a basal metazoan, in a set of experiments comprising more than 3.9 million days of observations of individual Hydra. Our data show that 2,256 Hydra from two closely related species in two laboratories in 12 cohorts, with cohort age ranging from 0 to more than 41 y, have extremely low, constant rates of mortality. Fertility rates for Hydra did not systematically decline with advancing age. This falsifies the universality of the theories of the evolution of aging that posit that all species deteriorate with age after maturity. The nonsenescent life history of Hydra implies levels of maintenance and repair that are sufficient to prevent the accumulation of damage for at least decades after maturity, far longer than the short life expectancy of Hydra in the wild. A high proportion of stem cells, constant and rapid cell turnover, few cell types, a simple body plan, and the fact that the germ line is not segregated from the soma are characteristics of Hydra that may make nonsenescence feasible. Nonsenescence may be optimal because lifetime reproduction may be enhanced more by extending adult life spans than by increasing daily fertility.
Elena K. Kupriyanova
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.
The fertility transition of Rwanda stagnated between 1992 and 2005 at a total fertility rate (TFR) of 6 children per woman. After 2005 the fertility decline resumed its course and the TFR dropped remarkably fast till 4.6. The period of the fertility stall coincided with a very disruptive period in
3. These TPFR increases were predominantly the consequence of changes in cohort childbearing age patterns, i.e. changes in the timing of fertility. They were not generated by fertility quantum increases. During this period in almost all the low-fertility countries TPFRs were rising while corresponding total cohort fertility rates were declining.
Sanchez, J J
The continued decline of marital fertility in Navarre, Spain, during the first few decades of the 20th century was associated with an increase in life expectancy and greater survival to adulthood. While the decline affected all social strata and geographical regions, it was not homogeneous, with some sectors of Navarrese society beginning the fertility transition earlier than others. Using data drawn from the nominal lists of the 1940 Spanish Census on married women aged 45-49 years, the author investigated the influence of differences in geographical origin, level of urbanization, father's occupation, level of religious devotion, and political factors upon the observed decline in marital fertility. The data support the originators of demographic transition theory, that the more urban populations, and therefore those with a higher percentage of the active population working in nonprimary sectors, led the fertility decline. The degree of a society's secularization also influenced the beginning of the decline of fertility and the levels reached.
Rodriguez-Wallberg, Kenny A; Oktay, Kutluk
The majority of children, adolescents, and young adults diagnosed with cancer today will become long-term survivors. The threat to fertility that cancer treatments pose to young patients cannot be prevented in many cases, and thus research into methods for fertility preservation is developing, aiming at offering cancer patients the ability to have biologically related children in the future. This paper discusses the current status of fertility preservation methods when infertility risks are related to surgical oncologic treatments, radiation therapy, or chemotherapy. Several scientific groups and societies have developed consensus documents and guidelines for fertility preservation. Decisions about fertility and imminent potentially gonadotoxic therapies must be made rapidly. Timely and complete information on the impact of cancer treatment on fertility and fertility preservation options should be presented to all patients when a cancer treatment is planned. PMID:24623991
Full Text Available Analysis of a natural fertility agrarian society with a multi-variate model of population ecology isolates three distinct phases of population growth following settlement of a new habitat: (1 a sometimes lengthy copial phase of surplus food production and constant vital rates; (2 a brief transition phase in which food shortages rapidly cause increased mortality and lessened fertility; and (3 a Malthusian phase of indefinite length in which vital rates and quality of life are depressed, sometimes strikingly so. Copial phase duration declines with increases in the size of the founding group, maximum life expectancy and fertility; it increases with habitat area and yield per hectare; and, it is unaffected by the sensitivity of vital rates to hunger. Transition phase duration is unaffected by size of founding population and area of settlement; it declines with yield, life expectancy, fertility and the sensitivity of vital rates to hunger. We characterize the transition phase as the Malthusian transition interval (MTI, in order to highlight how little time populations generally have to adjust. Under food-limited density dependence, the copial phase passes quickly to an equilibrium of grim Malthusian constraints, in the manner of a runner dashing over an invisible cliff. The three-phase pattern diverges from widely held intuitions based on standard Lotka-Verhulst approaches to population regulation, with implications for the analysis of socio-cultural evolution, agricultural intensification, bioarchaeological interpretation of food stress in prehistoric societies, and state-level collapse.
Alberto, R. T.; Damian, G. B.; Camaso, E. E.; Isip, M. F.
Land-cover maps were important for many scientific, ecological and land management purposes and during the last decades, rapid decrease of soil fertility was observed to be due to land use practices such as rice cultivation. High-precision land-cover maps are not yet available in the area which is important in an economy management. To assure accurate mapping of land cover to provide information, remote sensing is a very suitable tool to carry out this task and automatic land use and cover detection. The study did not only provide high precision land cover maps but it also provide estimates of rice production area that had undergone chemical degradation due to fertility decline. Land-cover were delineated and classified into pre-defined classes to achieve proper detection features. After generation of Land-cover map, of high intensity of rice cultivation, soil fertility degradation assessment in rice production area due to fertility decline was created to assess the impact of soils used in agricultural production. Using Simple spatial analysis functions and ArcGIS, the Land-cover map of Municipality of Quezon in Nueva Ecija, Philippines was overlaid to the fertility decline maps from Land Degradation Assessment Philippines- Bureau of Soils and Water Management (LADA-Philippines- BSWM) to determine the area of rice crops that were most likely where nitrogen, phosphorus, zinc and sulfur deficiencies were induced by high dosage of urea and imbalance N:P fertilization. The result found out that 80.00 % of fallow and 99.81% of rice production area has high soil fertility decline.
Over the past 2 decades, Japan, China, Singapore, Hong Kong, and South Korea have completed a demographic transition from high birth and death rates and runaway population growth to reduced fertility and mortality and population growth approaching replacement levels. Among the outcomes of fertility decline, 3 have particularly far reaching effects: 1) Changes in family types and structures. Marriage and family formation are postponed, childbearing is compressed into a narrow reproductive span that begins later and ends earlier, and higher-order births become rare. Large families are replaced by small ones, and joint and extended families tend to be replaced by nuclear families. 2) Shifts in the proportions of young and old. Declining fertility means that the population as a whole becomes older. Decreases in the proportion of children provides an opportunity to increase the coverage of education. Increases in the proportion of the elderly means higher medical costs and social and economic problems about care of the aged. 3) Changes in the work force. There is concern that low fertility and shortages of workers will cause investment labor-intensive industries to shift to countries with labor surpluses. Another outcome may be an increase in female participation in the work force. The potential consequences of rapid fertility decline have sparked debate among population experts and policy makers throughout Asia. Current family planning programs will emphasize: 1) offering a choice of methods to fit individual preferences; 2) strengthening programs for sexually active unmarried people; 3) encouraging child spacing and reproductive choice rather than simply limiting the number of births; 4) making information available on the side effects of various family planning methods; 5) providing special information and services to introduce new methods; and 6) promoting the maternal and child health benefits of breast feeding and birth spacing.
Gosden, Roger G
Fertility preservation has been practiced for at least 50 years using semen banking, pelvic surgery, and radiation shields, but in the past 20 years it has emerged as a rapidly growing subspecialty of reproductive medicine. A dramatic rise in survivorship of young cancer patients and the widespread postponement of family building to the later years of the female reproductive lifespan have been major driving forces. Throughout the history of fertility preservation, low temperature banking has played a pivotal role, first for gametes and later for embryos and immature germ cells, while ovarian transplantation recently began to contribute and spermatogonial stem cell transfer holds future promise for men and prepubertal boys. But there are significant risks with some diseases from reimplanting residual disease, which hopefully can be eliminated by new methods for purging the tissue and germ cell culture. Since all technologies are interim, cryopreservation as a mainstay in this field will likely be swept aside eventually by a stream of progress aimed at managing fertility preservation in vivo.
Satish K Gupta
Full Text Available It is imperative to understand the molecular basis of various steps involved during fertilization. In the manuscript by Bianchi et al.  a novel protein, Juno on egg membrane (oolemma has been characterized that binds to sperm specific protein, Izumo-1. Monoclonal antibodies against Juno inhibited in vitro fertilization. Juno knock-out female mice failed to deliver litters on mating. It is rapidly shed from oolemma after fertilization, suggesting its role in preventing polyspermy. Taken together these studies will help in our understanding of sperm-egg recognition mechanisms and also facilitate development of new fertility treatment regimens and novel contraceptives.
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.
Jensen, Eric R; Ahlburg, Dennis A
We model the impact of past migration on fertility, assessing the separate effects of relative urbanization of the destination, as a proxy for norms, and post-migration employment, as a proxy for opportunity costs. In the Philippines, we find that large fertility declines accompany post-migration employment. If not followed by work for pay, the estimated fertility impact of migration is small. We find little evidence of migrant selectivity in fertility, and offer speculative evidence that fertility disruption accompanying migration may be large enough to account for much of the apparent effect of normative adaptation.
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 ...
Hartemink, A.E.; Veldkamp, A.; Bai, Zhanguo
Land cover changes influence the biogeochemistry, hydrology, and climate of the earth. Studies that assessed land cover changes at the global scale mostly focused on: deforestation, cropland expansion, dry land degradation, urbanisation, pasture expansion, and agricultural intensification. For the
Perera, E L Sunethra J
This paper examines the fertility transition and its recent dynamics in Sri Lanka using data from Demographic and Health Surveys and Population Censuses. Fertility trends and patterns were analysed for two periods: 1953-2000 and 2000-2012. The findings revealed that Sri Lanka's fertility transition has been relatively rapid and has taken place over a period of about four decades to reach replacement level. Social and health-related factors, including decline in maternal and infant mortality, increase in women's education, changes in institutions, reproductive values and behaviour, and increased contraceptive use all contributed to bringing down the fertility level by 2000. However, in the 2006/07 Sri Lankan DHS and 2012 Population Census, a slight increase in Total Fertility Rate (TFR) to 2.3 and 2.4, respectively, was observed. Binary logistic regression estimates based on 2006/2007 DHS data were used to identify the significant predictors of fertility preferences of ever-married women. The analysis of factors affecting the likelihood of having a larger family (more than 2 children) revealed that lower educated women were more likely to have a higher number of children than their counterparts with a higher level of education. Women who lived in rural and estate (commercial area of 20 acres or more employing 10 or more labourers) sectors were 1.4 and 1.2 times, respectively, more likely to prefer more children compared with urban women. In terms of ethnic groups, Moor and Tamil women were 4.5 and 1.4 times, respectively, more likely to prefer more children than Sinhalese women. When the economic status of women was considered, the poorer women were 1.4 times more likely to desire a higher number of children compared with rich women, while women in the middle wealth quintile were 1.2 times more likely to desire more children. The findings suggest that the Sri Lankan government should re-visit population and reproductive health policy and family planning programmes
Lopez, Oscar L; Schwam, Elias; Cummings, Jeffrey
Numerous patient- and disease-related factors increase the risk of rapid cognitive decline in patients with Alzheimer's disease (AD). The ability of pharmacological treatment to attenuate this risk remains undefined.......Numerous patient- and disease-related factors increase the risk of rapid cognitive decline in patients with Alzheimer's disease (AD). The ability of pharmacological treatment to attenuate this risk remains undefined....
Full Text Available Kenny A Rodriguez-Wallberg,1,2 Kutluk Oktay3,4 1Karolinska Institutet, Department of Clinical Science, Intervention and Technology, Division of Obstetrics and Gynecology, 2Reproductive Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden; 3Innovation Institute for Fertility Preservation, Rye and New York, 4Department of Obstetrics and Gynecology, New York Medical College, Valhalla, NY, USA Abstract: The majority of children, adolescents, and young adults diagnosed with cancer today will become long-term survivors. The threat to fertility that cancer treatments pose to young patients cannot be prevented in many cases, and thus research into methods for fertility preservation is developing, aiming at offering cancer patients the ability to have biologically related children in the future. This paper discusses the current status of fertility preservation methods when infertility risks are related to surgical oncologic treatments, radiation therapy, or chemotherapy. Several scientific groups and societies have developed consensus documents and guidelines for fertility preservation. Decisions about fertility and imminent potentially gonadotoxic therapies must be made rapidly. Timely and complete information on the impact of cancer treatment on fertility and fertility preservation options should be presented to all patients when a cancer treatment is planned. Keywords: fertility preservation, cancer, cryopreservation, ovarian tissue transplantation, fertility-sparing surgery, cancer survival, quality of life
... 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 ...
... 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 - ...
Segelquist, Charles A.; Scott, Michael L.; Auble, Gregor T.
Establishment, growth, and survival of seedlings of Populus deltoides subsp. monilifera (plains cottonwood) were examined in an experimental facility simulating five rates of declining alluvial groundwater. The treatments were permanent saturation, drawdown rates of 0.4, 0.7, 2.9 cm/d and immediate drainage. The experiment was conducted outdoors in planters near Fort Collins, Colorado. Seedling survival was highest under the two slowest drawdown rates and declined significantly with faster drawdown rates. The highest growth rate was associated with the drawdown rate of 0.4 cm/d, in which mean shoot height was 2.4 cm and mean root length was 39 am 98 days after planting. Growth of shoots and roots was reduced both by saturated conditions and by the more rapid drawdown rates of 0.7 and 2.9 cm/d. No establishment was observed in the immediate drawdown treatment. Whereas maximum biomass accumulation is associated with the most gradual drawdown or saturated conditions, seedling establishing naturally under such conditions are also most likely to be removed by ice or subsequent flooding. Seedlings establishing in higher topographic positions, in contrast, are subject to increased mortality and reduced shoot growth, resulting from reduced soil moisture. Rapid root extension following establishment allows P. deltoides seedlings to grow across a wide range of groundwater drawdown rates, and thus a variety of positions across a gradient of riparian soil moisture. Our results indicate that in coarse alluvial sands of low fertility, 47% of germinating P. deltoides seeds were able to survive in associated with a drawdown rate of 2.9 cm/d and a final water table depth of 80 cm.
... 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 ...
Ouedraogo, Abdoulaye; Tosun, Mehmet S.; Yang, Jingjing
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...
Full Text Available Background: Mexican-American fertility is poorly understood because data limitations prevent researchers from accurately estimating the fertility levels of members of this group and from determining how their fertility changes within and across generations. Objective: Using binational data and an innovative methodological addressing key methodological limitations, I (1 estimate the fertility of Mexican Americans, (2 describe how selective Mexican migration to the United States is in terms of fertility, (3 document how Mexican-American fertility changes within and across generations, and (4 assess how educational selectivity and assimilation contribute to levels of fertility and fertility changes within and across generations. Results: My findings show that migration from Mexico to the United States is positively selective with respect to fertility. Among the migrants studied, there was a disruption in fertility in anticipation of migration, but a resumption of pre-migration fertility patterns and partial compensation for the earlier fertility loss after migration. Fertility levels among Mexican-Americans appear to be decreasing within and across generations, as immigrants deviate from their pre-migration fertility patterns and increasingly adopt those of whites. Nonetheless, Mexican-American fertility has not yet fully converged with white fertility. Educational assimilation explains a considerable portion of this fertility decline within and across generations. Comments: These findings highlight the importance of empirically observing the pre-migration fertility of immigrants.
Westoff, C F
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
Luca Gori; Luciano Fanti
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...
Oluwayemisi O Alaba
Results: Secondary or higher level of education of the mother, Yoruba ethnicity, Christianity, family planning use, higher wealth index, previous ... community and household effects contribute to the high fertility patterns in Nigeria. The hotspots for high ... high compared with Latin America and Asia where fertility declined from ...
-Saharan Africa. This article is trying to fill this gap by analysing the ZDHS data. The total fertility rate of Zimbabwe was close to 7 births during independence in 1980. However, it has declined to 3.8 in 2006. This does not only show that fertility ...
Fertility reductions in Bangladesh have contributed to a reduction in population growth from 2.5% between 1981 and 1991 to 2.3% in 1991. The average density of 800 persons/sq. km means competition for resources in a subsistence level economy. There is scarcity of land, food shortages, and an abundance of labor. Rapid socioeconomic development is not possible even with an average annual economic growth rate of 3.7% because of population growth. Birth control has doubled to 18.6% in 1991. Sterilization is no longer the primary means of contraception. Contraceptive usage increases are more widespread among young women who are spacing births. A recent study reports that fertility declines are due to increases in the expansion of family planning field workers over the past decade. Home distribution is considered compatible with sociocultural traditions. In 1990, there was 1 field worker/856 married women of reproductive age. 120 private voluntary organizations and the government provide contraceptive services. In 1989, 40% of pill and condom users obtained their supplies from commercial channels. This is possible because of the successful social marketing available through 130,000 commercial retail outlets. Nongovernmental organizations have also been given the freedom to operate independently from government programs. The International Center for Diarrheal Disease Research contributed to the contraceptive effort by field testing in Matlab, Aboynagar, and Sirajganj the introduction of door-to-door injectable contraception services and the building of satellite clinics. The information, education, and communications (IEC) activities also contributed to the 95.4% of women knowledgeable about at least 4 methods of contraception. Kantner and Noor reported that 14.4 million births were averted due to an increase in marriage age (from 16.3 years in 1974) to (17.7 years in 1989). Program efforts are being accelerated because of the 45% of the population that is presently under
Full Text Available The Parsis, a community of Iranian descent, are an important ethno-religious minority group in India. Over the past few decades this group has shown a sharp numerical decline. The Parsis in India are endogamous and children of women married outside the community are traditionally not accepted within the fold. This paper appraises the potential role of female intermarriage in Parsi population decline. Population projections were made under various assumptions of fertility and inter-marriage scenarios. Results show that given current fertility, acceptance of children of intermarried women would have a negligible impact on stemming the population decline, which is chiefly driven by extremely low fertility.
Østergaard, Christian Richter; Park, Eun Kyung
Most studies on regional clusters focus on identifying factors and processes that make clusters grow. However, sometimes technologies and market conditions suddenly shift, and clusters decline. This paper analyses the process of decline of the wireless communication cluster in Denmark....... The longitudinal study on the high-tech cluster reveals that technological lock-in and exit of key firms have contributed to decline. Entrepreneurship has a positive effect on the cluster’s adaptive capabilities, while multinational companies have contradicting effects by bringing in new resources to the cluster...
This paper examines fertility transition in Kinshasa, capital of the Democratic Republic of the Congo (DRC) and second-largest city in sub-Saharan Africa. Shapiro (1996) documented the onset of fertility transition in the city, using data from 1990. Women's education was strongly inversely related to fertility, beginning with secondary schooling, and increases in women's education were important in initiating fertility transition in the city. The paper uses data from the 2007 Demographic and Health Survey in the DRC to examine fertility in Kinshasa and assess fertility transition since 1990, a period characterized by severe adverse economic conditions in the DRC. Fertility transition has continued at a strong pace. In part this reflects increased educational attainment of women, but it appears also to be largely a consequence of enduring economic hardship. The ongoing fertility decline has been accompanied by substantial delays in entry to marriage and childbearing, reflecting adverse economic conditions, which in turn have contributed to continuing declines in fertility.
Kennes, John; Knowles, John
, in conjunction with US survey data, to explore the impact of marital prospects on the fertility decisions of unmarried women. We find that the decline, from the 1970s to 1995, in marriage rates of unmarried women with no children, can account for the dramatic rise in unmarried women’s share of births over...
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.
National Oceanic and Atmospheric Administration, Department of Commerce — This programs derives a table of secular change in magnetic declination for a specified point in the conterminous United States. It utilizes the USD polynomial and...
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.
David R. Hall
interest from demographers. Despite the fact that researchers have extensively modeled recent demographic changes such as skyrocketing divorce rates, rising common-law union formation, delayed childbearing, and the decline to belowreplacement fertility levels, our understanding of the causes of these trends, and the possible connections between them remains theoretically fragmented and incomplete. The goal of this paper is to advance our understanding in this area by exploring the insights on modern family formation of prominent sociologist Anthony Giddens. Specifically, this study examines whether Giddens’ “pure relationship” concept can shed light on the trend toward very low fertility. The results of this inquiry suggest that couples in both marriages and common-law unions who conform to key aspects of Giddens pure relationship are more likely to have uncertain or below-replacement fertility intentions, and less likely to embrace above-replacement fertility goals.
Skakkebaek, Niels E; Jørgensen, Niels; Main, Katharina M
Summary The decreasing trends in fertility rates in many industrialized countries are now so dramatic that they deserve much more scientific attention. Although social and behavioural factors undoubtedly play a major role for these trends, it seems premature, and not based on solid information...... and molecular biologists. This research effort can hardly be carried out without major support from governments and granting agencies making it possible to fund collaborative projects within novel research networks of scientists....
In an attempt to better understand the process through which the family planning (FP) programs and socioeconomic developments in China affect fertility, women's participation in fertility discussions with their husbands are examined as an intermediate factor in a study based on results of a random survey of 6654 ever-married women of reproductive age from 7 cities and 30 counties of Guangdong. First, it must be noted that Chinese couples do have individual choices (albeit quite limited ones) about their fertility; they can choose to follow or ignore government policy or they can choose to remain childless. The present study has 3 major hypotheses: 1) the more a woman is involved in fertility discussions with her husband, the fewer children she will have; 2) urban women with a higher educational status will be more likely to have such discussions; and 3) women who are contacted individually by FP personnel are more likely to be involved in fertility discussions. After a discussion of data collection and variables (number of living children, education of wife and husband, age at marriage, residence, living with parents, contacted by FP personnel, and discussion with husband), the results are presented in terms of zero-order correlation coefficients indicating their relationships. The bivariate analysis supported the hypotheses. Multiple regression analysis showed that age at marriage, education of wives and husbands, FP contacts, and participation in discussions remain significant fertility determinants (but the correlation between fertility and residence becomes trivial). A further regression model indicated that a woman's educational attainment is the most significant positive indication of their participation in fertility discussions. These results imply that as women's status continues to improve in China and the deeply-rooted patriarchal tradition loses hold, increased gender equity and education will influence a fertility decline. FP personnel could also
Mu, Zhen; Hu, Xue-Feng; Cheng, Chang; Luo, Zhi-qing
To study the effects of different fertilizer applications on soil enzyme activity, tomato plant growth and tomato yield and quality, a field experiment on tomato cultivation was carried out in the suburb of Shanghai. Three fertilizer treatments, chemical fertilizer (CF) (N, 260 g/kg; P, 25.71g/kg; K, 83.00g/kg), rapeseed cake manure (CM) (N, 37.4 g/kg; P, 9.0 g/kg; K, 8.46 g/kg), crop-leaf fermenting manure (FM) (N, 23.67 g/kg; P, 6.39 g/kg; K 44.32 g/kg), and a control without using any fertilizers (CK), were designed. The total amounts of fertilizer application to each plot for the CF, CM, FM and CK were 0.6 kg, 1.35 kg, 3.75 kg and 0 kg, respectively, 50% of which were applied as base fertilizer, and another 50% were applied after the first fruit picking as top dressing. Each experimental plot was 9 m2 (1 m × 9 m) in area. Each treatment was replicated for three times. No any pesticides and herbicides were applied during the entire period of tomato growth to prevent their disturbance to soil microbial activities. Soil enzyme activities at each plot were constantly tested during the growing period; the tomato fruit quality was also constantly analyzed and the tomato yield was calculated after the final harvesting. The results were as follows: (1) Urease activity in the soils treated with the CF, CM and FM increased quickly after applying base fertilizer. That with the CF reached the highest level. Sucrase activity was inhibited by the CF and CM to some extent, which was 32.4% and 11.2% lower than that with the CK, respectively; while that with the FM was 15.7% higher than that with the CK. Likewise, catalase activity with the CF increased by 12.3% - 28.6%; that with the CM increased by 87.8% - 95.1%; that with the FM increased by 86.4% - 93.0%. Phosphatase activity with the CF increased rapidly and reached a maximum 44 days after base fertilizer application, and then declined quickly. In comparison, that with the CM and FM increased slowly and reached a maximum
Thornton, Arland; Binstock, Georgina; Yount, Kathryn M; Abbasi-Shavazi, Mohammad Jalal; Ghimire, Dirgha; Xie, Yu
Many scholars have offered structural and ideational explanations for the fertility changes occurring around the world. This paper focuses on the influence of developmental idealism-a schema or set of beliefs endorsing development, fertility change, and causal connections between development and fertility. Developmental idealism is argued to be an important force affecting both population policy and the fertility behavior of ordinary people. We present new survey data from ordinary people in six countries-Argentina, China, Egypt, Iran, Nepal, and the United States-about the extent to which developmental idealism is known and believed. We ask individuals if they believe that fertility and development are correlated, that development is a causal force in changing fertility levels, and that fertility declines enhance the standard of living and intergenerational relations. We also ask people about their expectations concerning future trends in fertility in their countries and whether they approve or disapprove of the trends they expect. The data show widespread linkage in the minds of ordinary people between fertility and development. Large fractions of people in these six settings believe that fertility and development are correlated, that development reduces fertility, and that declines in fertility foster development. Many also expect and endorse future declines in fertility.
Grace, Kathryn; Sweeney, Stuart
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.
Effective rate-time analysis during a declining production in an oil or gas wells is an important tool for establishing a successful management. The reasons behind the production decline include reservoir, fracture and well conditions. A well's decline rate is transient, signifying that the pressure wave propagates freely from the wellbore, leading to depletion when the outer boundary for the well is reached and to the wave propagation coming to a halt. This thesis studies the transient decline, with emphasis on a horizontal well with fracture wellbore responses. It also deals with the depletion decline, investigating the wellbore pressure responses for a vertical well producing under variable rate conditions of Arps decline. The well decline model solutions are analytical, and the modelling itself is carried out in two steps. The first step involves modelling the transient well responses of a multi fractured horizontal well. These responses originate from an infinitive reservoir and are considered as full-time rate-time responses. Multi-fractured horizontal well rate-time responses represent the solutions to a diffusion equation with varying boundary conditions and different fracture options (i.e., with or without fracture, a variety of fracture orientations, various fracture lengths, etc). The transient model calculates individual fracture rates, productivity indexes and an equivalent wellbore radius for the multi-fractured well. For the transient decline of a fractured-horizontal well model, well data is matched and the reservoir diagnosis and production prognosis are improved through the individual fracture production, with a model screening ability, and novel model features that can handle wellbore conditions changing from rate-to-pressure. Screening analyses can generate valuable information for fracture diagnosis in addition to a well and fracture production prognosis. Further model runs are carried out to match the real well data. The model solution is
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).
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...
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...
Fishery decline is interpreted in a number of ways. These interpretations vary considerably from one observer to another, depending on the level at which each interacts with the fishery. Fish stock assessments, predominantly carried out through environmental impact statements, are often not
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
Hiday, V A
3 groups of women are compared in this study of the effect of migration on fertility in a less developed country: 1) rural sedentary; 2) rural to rural migrants; and 3) rural to urban migrants. The data are from a 1970 household interview study conducted by the Institute of Behavioral Science, University of Colorado in Magsayay and Matanao, Davao Province, Mindanao, the Philippines. Social, economic, and mortality data were gathered from the household head and/or spouse for each household member and each child living elsewhere. Reproductive histories were obtained only from women for all women 15 years of age and older living in the 2 rural communities and living elsewhere. Age specific fertility rates and child woman ratios showed a declining gradient of fertility with social distance from the rural home communities. Age at marriage and education were positively associated with distance from the home communities and negatively associated with fertility. The data provide support for the hypothesis that recent migration is innovative, engaged in by more modernized persons who are motivated by aspiration to new goals, thus migration has a negative effect on fertility. Urbanization had its major impact after peak fertility years, 20-29, influencing urban migrants to bring their fertility under voluntary control. No such curtailment appeared in the late reproductive behavior of rural sedentary or migrant women. Urbanization seems to have a negative effect on fertility independent of migration. Young migrant women, in their teens, particularly those migrating to urban areas, did not fit the social mobility model; they tended to complete fewer years of school and married at an earlier age. These young urban migrants also had higher fertility than both rural sedentary and rural migrant females while in their teen years.
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.
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. ...
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.
... 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 ...
... 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 ...
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. ...
... 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 ...
Mac Dougall, K; Beyene, Y; Nachtigall, R D
What do older women understand of the relationship between age and fertility prior and subsequent to delivering their first child? Women who were first-time parents over the age of 40 did not accurately perceive the relationship between age and fertility prior to conceiving with IVF. While increases in women's age at their first birth have been most pronounced in relatively older women, the rapidity of fertility decline is not appreciated by most non-infertility specialist physicians, the general public or men and women who are delaying childbearing. Qualitative retrospective interviews were conducted from 2009 to 2011 with 61 self-selected women who were patients in one of two fertility clinics in the USA. All participants had delivered their first child following IVF when the woman was 40 years or older. The data include women's responses to the semi-structured and open-ended interview questions 'What information did you have about fertility and age before you started trying to get pregnant?' and 'What did you learn once you proceeded with fertility treatment?' Of the women, 30% expected their fertility to decline gradually until menopause at around 50 years and 31% reported that they expected to get pregnant without difficulty at the age of 40. Reasons for a mistaken belief in robust fertility included recollections of persistent and ongoing messaging about pregnancy prevention starting in adolescence (23%), healthy lifestyle and family history of fertility (26%), and incorrect information from friends, physicians or misleading media reports of pregnancies in older celebrity women (28%). Participants had not anticipated the possibility that they would need IVF to conceive with 44% reporting being 'shocked' and 'alarmed' to discover that their understanding of the rapidity of age-related reproductive decline was inaccurate'. In retrospect, their belated recognition of the effect of age on fertility led 72% of the women to state that they felt 'lucky' or had
Jesús J. Sánchez-Barricarte
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.
Faria, V E
Since some argue that the recent and marked fertility decline experienced in Brazil is related to institutional changes resulting from public policies promoted by the federal government since 1964, the author attempts to shed light upon the role played by such policies upon fertility regulation. Fertility in Brazil and the main explanatory theories are first discussed. The paper then considers the role played by the growth of the consumer society, social security coverage, mass media, and the medicalization of society upon changing patterns of fertility regulation in Brazil. The discussion of government policies and fertility regulation includes consideration of consumer credit policy, social security benefit policy, telecommunications policy, and health care policy. One salient conclusion of the analysis is that the lack of a policy to provide fertility regulation mechanisms other than through the marketplace hurts relatively poor populations.
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.
Lopez, Oscar L; Schwam, Elias; Cummings, Jeffrey
Numerous patient- and disease-related factors increase the risk of rapid cognitive decline in patients with Alzheimer's disease (AD). The ability of pharmacological treatment to attenuate this risk remains undefined....
Markow, T A
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.
Skakkebæk, Niels E.; Jørgensen, Niels; Main, Katharina M.
Summary The decreasing trends in fertility rates in many industrialized countries are now so dramatic that they deserve much more scientific attention. Although social and behavioural factors undoubtedly play a major role for these trends, it seems premature, and not based on solid information......, to conclude that these trends can be ascribed to social and behavioural changes alone. There is evidence to suspect that changing lifestyle and increasing environmental exposures, e.g. to endocrine disrupters, are behind the trends in occurrence of male reproductive health problems, including testis cancer...... and molecular biologists. This research effort can hardly be carried out without major support from governments and granting agencies making it possible to fund collaborative projects within novel research networks of scientists....
Whalen, S. C.; Phillips, R. L.; Fischer, E. N.
Contemporary agriculture is characterized by the intensive production of livestock in confined facilities and land application of stored waste as an organic fertilizer. Emission of nitrous oxide (N2O) from receiving soils is an important but poorly constrained term in the atmospheric N2O budget. In particular, there are few data for N2O emissions from spray fields associated with industrial scale swine production facilities that have rapidly expanded in the southeastern United States. In an intensive, 24-day investigation over three spray cycles, we followed the time course for changes in N2O emission and soil physicochemical variables in an agricultural field irrigated with liquid lagoonal swine effluent. The total N (535 mg L-1) of the liquid waste was almost entirely NH4+-N (>90%) and thus had a low mineralization potential. Soil profiles for nitrification and denitrification indicated that >90% of potential activity was localized in the surface 20 cm. Application of this liquid fertilizer to warm (19° to 28°C) soils in a form that is both readily volatilized and immediately utilizable by the endogenous N-cycling microbial community resulted in a sharp decline in soil NH4+-N and supported a rapid but short-lived (i.e., days) burst of nitrification, denitrification, and N2O emission. Nitrous oxide fluxes as high as 9200 μg N2O-N m-2 h-1 were observed shortly after fertilization, but emissions decreased to prefertilization levels within a few days. Poor correlations between N2O efflux and soil physicochemical variables (temperature, moisture, NO3--N, NH4+-N) and fertilizer loading rate point to the complexity of interacting factors affecting N2O production and emission. Total fertilizer N applied and N2O-N emitted were 29.7 g m-2 (297 kg N ha-1) and 395 mg m-2, respectively. The fractional loss of applied N to N2O (corrected for background emission) was 1.4%, in agreement with the mean of 1.25% reported for mineral fertilizers. The direct effects of fertilizer
Devassine, M; Henry, F; Guerin, P; Briand, X
The conventional agriculture leads to some important pollution of ground water (particularly, by nitrates). The solution is the coating of fertilizers by degradable polymers. In this work, we have studied the water vapour and liquid diffusion through polymer films detached from their support. Therefore, we may classify polymers as a function of their properties like water vapour and liquid barrier. We may choose the best polymer(s) for coating.coated fertilizers by chosen polymer(s) with mechanical techniques such as fluidised bed and pan coating. Moreover, the electron microscopy used to see the quality of the wall has showed the presence of pores due to the rapid evaporation of solvent. A drying in air current and an annealing could be done to avoid this problem.followed the ions release of fertilizers immersed in distilled water by conductimetry. The more interesting result was obtained with fertilizers coated by polylactic acid. In effect, the total release reached three weeks.
Sear, Rebecca; Lawson, David W; Kaplan, Hillard; Shenk, Mary K
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).
This work summarizes a paper by Cynthia B. Lloyd and Serguey Ivanov entitled "The Effects of Improved Child Survival on Family Planning Practice and Fertility" that was presented at the October 1987 conference in Nairobi on the health benefits of family planning for women and children. The paper presented results of a systematic literature review that sought to answer 2 questions: 1) do improved prospects of child survival reduce fertility, and 2) if so, what role does family planning play in the process. The 4 parts of the study defined the theoretical framework of the analysis, examined socioeconomic factors that could influence family building strategies, reviewed empiric research on the subject, and discussed policy implications. Improved survival prospects for children have 4 different effects which promote fertility decline. The transition effect refers to the parents' growing awareness that they can influence future events. The physiologic effect results when lactation is uninterrupted by early death of the child. When fertility behavior becomes more calculated and less fatalistic, demand and supply effects enter into play. The relationship between fertility and mortality is 2-directional. Socioeconomic factors determine the number of surviving children desired by a couple. In the traditionally agricultural societies of sub-Saharan Africa, the economic value of children far exceeds their costs, which at any rate are shared by the extended family and the community at large. The age distribution of death largely determines the predictability of child survival. High mortality after the 1st year as in Sahel countries which have the highest child morality rates in the world is unfavorable to family planning. The distribution of causes of death is also important because parents are more likely to notice improved survival prospects and change their fertility expectations accordingly if they themselves helped improve conditions rather than merely benefitting from
Thomas D. Landis; R. Kasten Dumroese
Since World War II, synthetic fertilizers have been used almost exclusively to grow forest and native plant nursery crops because they are quickly soluble and readily taken up by crops, producing the rapid growth rates that are necessary in nursery culture. In recent years, however, a wide variety of new organic fertilizers have become available. We divided these...
Full Text Available Periodontitis is common in the elderly and may become more common in Alzheimer's disease because of a reduced ability to take care of oral hygiene as the disease progresses. Elevated antibodies to periodontal bacteria are associated with an increased systemic pro-inflammatory state. Elsewhere raised serum pro-inflammatory cytokines have been associated with an increased rate of cognitive decline in Alzheimer's disease. We hypothesized that periodontitis would be associated with increased dementia severity and a more rapid cognitive decline in Alzheimer's disease. We aimed to determine if periodontitis in Alzheimer's disease is associated with both increased dementia severity and cognitive decline, and an increased systemic pro inflammatory state. In a six month observational cohort study 60 community dwelling participants with mild to moderate Alzheimer's Disease were cognitively assessed and a blood sample taken for systemic inflammatory markers. Dental health was assessed by a dental hygienist, blind to cognitive outcomes. All assessments were repeated at six months. The presence of periodontitis at baseline was not related to baseline cognitive state but was associated with a six fold increase in the rate of cognitive decline as assessed by the ADAS-cog over a six month follow up period. Periodontitis at baseline was associated with a relative increase in the pro-inflammatory state over the six month follow up period. Our data showed that periodontitis is associated with an increase in cognitive decline in Alzheimer's Disease, independent to baseline cognitive state, which may be mediated through effects on systemic inflammation.
Ide, Mark; Harris, Marina; Stevens, Annette; Sussams, Rebecca; Hopkins, Viv; Culliford, David; Fuller, James; Ibbett, Paul; Raybould, Rachel; Thomas, Rhodri; Puenter, Ursula; Teeling, Jessica; Perry, V Hugh; Holmes, Clive
Periodontitis is common in the elderly and may become more common in Alzheimer's disease because of a reduced ability to take care of oral hygiene as the disease progresses. Elevated antibodies to periodontal bacteria are associated with an increased systemic pro-inflammatory state. Elsewhere raised serum pro-inflammatory cytokines have been associated with an increased rate of cognitive decline in Alzheimer's disease. We hypothesized that periodontitis would be associated with increased dementia severity and a more rapid cognitive decline in Alzheimer's disease. We aimed to determine if periodontitis in Alzheimer's disease is associated with both increased dementia severity and cognitive decline, and an increased systemic pro inflammatory state. In a six month observational cohort study 60 community dwelling participants with mild to moderate Alzheimer's Disease were cognitively assessed and a blood sample taken for systemic inflammatory markers. Dental health was assessed by a dental hygienist, blind to cognitive outcomes. All assessments were repeated at six months. The presence of periodontitis at baseline was not related to baseline cognitive state but was associated with a six fold increase in the rate of cognitive decline as assessed by the ADAS-cog over a six month follow up period. Periodontitis at baseline was associated with a relative increase in the pro-inflammatory state over the six month follow up period. Our data showed that periodontitis is associated with an increase in cognitive decline in Alzheimer's Disease, independent to baseline cognitive state, which may be mediated through effects on systemic inflammation.
Bacci, M L
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
Onduru, D.D.; Jager, de, AG Bram; (KARI) Gachini, G.N.; Diop, J.M.
This working paper discusses the impact of a multi-institutional research programme in low potential areas of Kenya. The programme elaborated nutrient balances, combined with economic analysis, to better understand causes and effects of soil fertility decline. Alongside, better soil fertility management practices were developed using a participatory technology approach. This paper assesses to what extent farmers changed their practices, if the program has influenced way of working with extens...
Because of increase in unemployment, and the consequent lack of job security and exclusion it leads to, the positive bond associated with work has, globally, been broken. Success both in professional and private life has become a competing aspiration, with a decreasing tendency to sacrifice one's private life for one's work. Physicians are also affected by this tendency and a major link has been broken in the attachment of the medical corps to their work. The fact that work is considered as a declining value, also in the health sector, corresponds to specific economic and societal phenomena. The repositioning of health in the economic activity, the re-definition of the medical professions with their specific competence, are presently under discussion.
Malik, Abdul; Mertz, Ole; Fensholt, Rasmus
Mangrove forests in the tropics and subtropics grow in saline sediments in coastal and estuarine environments. Preservation of mangrove forests is important for many reasons, including the prevention of coastal erosion and seawater intrusion; the provision of spawning, nursery, and feeding grounds...... and severe mangrove loss with serious consequences. The mangrove forests of the Takalar District, South Sulawesi, are studied here as a case area that has suffered from degradation and declining spatial extent during recent decades. On the basis of a post-classification comparison of change detection from...... satellite imagery and a survey of households, we provide an estimate of the mangrove change in the Takalar District during 1979–2011 and the consequences of those changes. Mangrove forest areas were reduced by 66.05 % (3344 hectares) during the 33-year period of analysis, and the biggest annual negative...
David R. Houston
Only a few episodes of sugar maple dieback or decline were recorded during the first half of the 20th Century. In contrast, the last 50 years have provided numerous reports of both urban and forest dieback/decline. In the late 1950s, a defoliation-triggered decline, termed maple blight, that occurred in Wisconsin prompted the first comprehensive, multidisciplinary...
Tash, J. S.; Kim, S.; Schuber, M.; Seibt, D.; Kinsey, W. H.
Sperm and other flagellates swim faster in microgravity (microG) than in 1 G, raising the question of whether fertilization is altered under conditions of space travel. Such alterations have implications for reproduction of plant and animal food and for long-term space habitation by man. We previously demonstrated that microG accelerates protein phosphorylation during initiation of sperm motility but delays the sperm response to the egg chemotactic factor, speract. Thus sperm are sensitive to changes in gravitational force. New experiments using the NiZeMi centrifugal microscope examined whether low hypergravity (hyperG) causes effects opposite to microG on sperm motility, signal transduction, and fertilization. Sperm % motility and straight-line velocity were significantly inhibited by as little as 1.3 G. The phosphorylation states of FP130, an axonemal phosphoprotein, and FP160, a cAMP-dependent salt-extractable flagellar protein, both coupled to motility activation, showed a more rapid decline in hyperG. Most critically, hyperG caused an approximately 50% reduction in both the rate of sperm-egg binding and fertilization. The similar extent of inhibition of both fertilization parameters in hyperG suggests that the primary effect is on sperm rather than eggs. These results not only support our earlier microG data demonstrating that sperm are sensitive to small changes in gravitational forces but more importantly now show that this sensitivity affects the ability of sperm to fertilize eggs. Thus, more detailed studies on the impact of space flight on development should include studies of sperm function and fertilization.
Santella, Luigia; Vasilev, Filip; Chun, Jong T
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.
Chaput, Laure; Grémeau, Anne-Sophie; Vorilhon, Solène; Pons, Hanae; Chabrot, Cécile; Grèze, Victoria; Pouly, Jean-Luc; Brugnon, Florence
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.
Restrepo, June; Bernardin, Linda; Hammeke, Thomas
Alexander disease is a neurological condition associated with prominent white matter deterioration. Its rarity and relatively rapid disease course have provided limited understanding into the cognitive effects of the illness. We report the serial neuropsychological findings of a 21-year-old with normal development and no medical history until age 9, when he experienced refractory sinusitis, stabbing headaches with vertigo, disorientation, and decline in academic and social settings. An MRI scan of the brain found acute demyelinating encephalomyelitis, with a preponderance of white matter degeneration in the bilateral frontal lobes. Interval MRIs showed continued degeneration. Confirmation of Alexander disease was made at age 20 through genetic testing. Four evaluations completed from ages 15 to 21 showed impairment across all cognitive domains. Cognitive deficits were most prominent in new learning and recent memory, executive functions, and fine motor dexterity, and less apparent in information processing and visual scanning speed. These results present evidence for a particular cognitive pattern in individuals with juvenile-onset Alexander disease. Despite extensive white matter degeneration in the frontal lobes, certain tasks associated with frontal lobe integrity were relatively preserved. Further research into the neuropsychological presentation of the subtypes of Alexander disease can enhance diagnostic clarity and treatment planning.
Changing demographic trends and projections of the survival and fertility rates of each generation have been a topic of great interest to not only demographers and epidemiologists but also to evolutionary biologists and reproductive endocrinologists. Compelling evolutionary theories suggest that there is an inverse association between fertility and longevity. Multiple historic, demographic, and current studies have since been conducted to test this theory, but the results have been inconclusive. The average number of children born to each woman has been declining progressively in developed countries during recent decades. This is in part due to changes in the behavior of couples but also to environmental factors. While improved accessibility to assisted reproductive technology can relieve some of the burden of infertility on these couples and lessen the problem of low total fertility rates in many developed countries, it is not enough to overcome the overall decrease in total fertility rates that we have witnessed in recent decades. This article critically reviews some important studies and provides an overview of this ongoing debate, while highlighting the relevance of trying to understand the possible mechanisms that may link fertility and infertility to longevity. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Hall, David R.
Full Text Available Of the many changes which have characterized the second demographic transition, shifts in fertility and union formation have attracted a great deal of interest from demographers. Despite the fact that researchers have extensively modeled recent demographic changes such as skyrocketing divorce rates, rising common-law union formation, delayed childbearing, and the decline to below-replacement fertility levels, our understanding of the causes of these trends, and the possible connections between them remains theoretically fragmented and incomplete. The goal of this paper is to advance our understanding in this area by exploring the insights on modern family formation of prominent sociologist Anthony Giddens. Specifically, this study examines whether Giddens' "pure relationship" concept can shed light on the trend toward very low fertility. The results of this inquiry suggest that couples in both marriages and common-law unions who conform to key aspects of Giddens pure relationship are morel likely to have uncertain or below-replacement fertility intentions, and less likely to embrace above-replacement fertility goals.
Krolewski, Andrzej S.; Skupien, Jan; Rossing, Peter
A new model of diabetic nephropathy in type 1 diabetes emerged from our studies of Joslin Clinic patients. The dominant feature is progressive renal decline, not albuminuria. This decline is a unidirectional process commencing while patients have normal renal function and, in the majority......, progressing steadily (linearly) to end-stage renal disease (ESRD). While an individual's rate of renal decline is constant, the estimated glomerular filtration rate (eGFR) slope varies widely among individuals from –72 to –3.0 ml/min/year. Kidney Disease: Improving Global Outcomes guidelines define rapid......, that very fast and fast decline from normal eGFR to ESRD within 2 to 10 years constitutes 50% of the Joslin cohort. In this review we present data about frequency of fast decliners in both diabetes types, survey some mechanisms underlying fast renal decline, discuss methods of identifying patients at risk...
Full Text Available TRACT Fertilizers is one activities of maintenance plants that an important role to productivity plants. Without right fertilizing, cacao farms are many setbacks especially in quality of land. Land quality decline because reduction of nutrient in land, damage characteristics of biological or physical and more deplete substantially thickness of land. Nutrient reduction has occur caused by activities of harvest, washing, denitrification, and erosion that occurred in area of cacao plants roots. Damage of biological and physical of land include land aggregate damage, decreased stability of structure, decreased organic matter, and reducing amount of and activities of organisms that live in land. Efforts to increase land fertility can be with gift fertilizer. Study using a Random Group Design with 3 replication, with fertilizer treatment: P1 = Control (farmers; P2 = natural fertilizer 5 kg; P3 = natural fertilizer 5 kg+ 5 g urea + 5 g SP-36, and P4 = natural fertilizer 5 kg+ 5 g SP-36+ 5 g (KC1. Results of study showed that giving of manure and organic matter are significantly different with farmers (control, but best treatment is found on gift manure combined fertilizer anorganic (P3 provides growth and number of best fruit.
K.H. Johnsen; J.R. Butnor; C. Maier; R. Oren; R. Pangle; L. Samuelson; J. Seiler; S.E. McKeand; H.L. Allen
The extent of fertilization of southern pine forests is increasing rapidly; industrial fertilization increased from 16,200 ha per year in 1988, to 344,250 ha in 1998. Fertilization increases stand productivity and can increase carbon (C) sequestration by: 1) increasing above-ground standing C; 2) increasing C stored in forest products; and 3) increasing below-ground...
Organic fertilizers apart from releasing nutrient to the soil also improve its physical properties, which enhance plant growth and development. However, release of nutrient is slow in organic fertilizers, but more lasting compared to the faster release of nutrients by inorganic fertilizers, which are often lost rapidly by leaching in ...
Vines, Timothy; Andrew, Rose; Debarré, Florence; Bock, Dan; Franklin, Michelle; Gilbert, Kimberley; Moore, Jean-Sébastien; Renaut, Sébastien; Rennison, Diana J
Policies ensuring that research data are available on public archives are increasingly being implemented at the government , funding agency [2-4], and journal [5,6] level. These policies are predicated on the idea that authors are poor stewards of their data, particularly over the long term , and indeed many studies have found that authors are often unable or unwilling to share their data [8-11]. However, there are no systematic estimates of how the availability of research data changes with time since publication. We therefore requested datasets from a relatively homogenous set of 516 articles published between 2 and 22 years ago, and found that availability of the data was strongly affected by article age. For papers where the authors gave the status of their data, the odds of a dataset being extant fell by 17% per year. In addition, the odds that we could find a working email address for the first, last or corresponding author fell by 7% per year. Our results reinforce the notion that, in the long te...
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…
Full Text Available This paper investigates the aggregate relationship between cohort fertility and female educational attainment in Croatia. Numerous demographic studies have examined the link between fertility and the level of education. However, newer research indicates that the field of education might also play a role when trying to explain fertility behavior. We contribute to existing literature on macro-level factors related to reproductive outcomes by considering both the level and field of education as possible sources of cohort fertility differentials. The main goal of the present study is to assess the effect of structural changes in educational attainment on cohort fertility decline by means of demographic decomposition techniques. Our analysis is based on detailed 2011 Census data, which provide information on the number of livebirths by mother’s year of birth, birth order, marital status and educational attainment (i.e. the level and field of education. The results of our decomposition analyses reveal the dominance of the structural effect in explaining the overall completed fertility decline in Croatia. We assumed that the changing distribution of women by field of education at least partially accounts for the observed patterns in completed fertility but found no strong evidence in support of the outlined hypothesis.
Baake, Verena; Reijntjes, Robert H A M; Dumas, Eve M; Thompson, Jennifer C; Roos, Raymund A C
In Huntington's Disease (HD) cognitive decline can occur before unequivocal motor signs become apparent. As cognitive decline often starts early in the course of the disease and has a progressive nature over time, cognition can be regarded as a key target for symptomatic treatment. The specific progressive profile of cognitive decline over time is unknown. The aim of this study is to quantify the progression of cognitive decline across all HD stages, from pre-motormanifest to advanced HD, and to investigate if CAG length mediates cognitive decline. In the European REGISTRY study 2669 HD expansion gene carriers underwent annual cognitive assessment. General linear mixed models were used to model the cognitive decline for each cognitive task across all disease stages. Additionally, a model was developed to evaluate the cognitive decline based on CAG length and age rather than disease stage. There was significant cognitive decline on all administered tasks throughout pre-motormanifest (close to estimated disease onset) participants and the subsequent motormanifest participants from stage 1 to stage 4. Performance on the Stroop Word and Stroop Color tests additionally declined significantly across the two pre-motormanifest groups: far and close to estimated disease onset. The evaluation of cognition performance in relation to CAG length and age revealed a more rapid cognitive decline in participants with longer CAG length than participants with shorter CAG length over time. Cognitive performance already shows decline in pre-motormanifest HD gene expansion carriers and gradually worsens to late stage HD. HD gene expansion carriers with certain CAG length have their own cognitive profile, i.e., longer CAG length is associated with more rapid decline. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pantazis, Athena; Clark, Samuel J
This study aims to understand trends in global fertility from 1950-2010 though the analysis of age-specific fertility rates. This approach incorporates both the overall level, as when the total fertility rate is modeled, and different patterns of age-specific fertility to examine the relationship between changes in age-specific fertility and fertility decline. Singular value decomposition is used to capture the variation in age-specific fertility curves while reducing the number of dimensions, allowing curves to be described nearly fully with three parameters. Regional patterns and trends over time are evident in parameter values, suggesting this method provides a useful tool for considering fertility decline globally. The second and third parameters were analyzed using model-based clustering to examine patterns of age-specific fertility over time and place; four clusters were obtained. A country's demographic transition can be traced through time by membership in the different clusters, and regional patterns in the trajectories through time and with fertility decline are identified.
Sonneveld, C.; Voogt, W.
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
Heer, D M
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.
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.
van Poppel, F.W.A.; Reher, D.S.; Sanz-Gimeno, A.; Sanchez-Dominguez, M.; Beekink, E.
BACKGROUND According to classic demographic transition theory, mortality change is the key factor that triggers a decline in fertility. Research on this topic has mostly relied on aggregate or time series data. Since fertility is based on the joint decisions of couples when confronted with specific
Lightbourne R; Singh, S; Green, C P
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.
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.
Jennifer Juzwik; Ji-Huyn Park; Linda Haugen
Research continued through the 2010 field season on the etiology of hickory decline that is characterized by thinning crowns with small, yellow leaves and hickory bark beetle attack on the upper main stem. This research is part of a larger project initiated in 2006 to assess the distribution and determine the cause(s) of Forest Health Monitoring reported decline and...
Full Text Available The establishment of democracy in the communist countries, which generated profound social and economic transformation, was accompanied by a decline in fertility. We attempt to provide an overall survey on fertility since 1989 in ten Central and Eastern European Countries, members of the European Union, and to identify the variables which explain the fertility decline. We will use univariate and multivariate statistical analysis to identify disparities between the ten countries, and the variables which explain these differences. Also, we developed a panel econometric model to confirm the hypothesis of a similar pattern of evolution for fertility in these countries and that the decline in fertility can be explained both through demographic and economic variables. The decline in fertility can be explained by economic growth, marriage, divorce, abortion, and migration. The empirical evidence presented in this paper supports the view that the decline in fertility over the 1989s represents the continuation of a longstanding trend of the previous period, according to the demographic transition theory, but its speed and magnitude has been influenced by the new social and economic landscape. These results can be useful for public authorities of the CEE countries to rethinking demographic policies and to ensure the sustainability of demographic growth.
The spectacularly early decline of French fertility is one of the great puzzles of economic history. There are no convincing explanations for why France entered a fertility transition over a century before anywhere else in the world. This analysis links highly detailed individual level fertility life histories to wealth at death data for four rural villages in transition-era France, 1750-1850. The results show that it was the richest groups who reduced their family size first and that they us...
Veerkamp, R.F.; Beerda, B.
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
Muhoza Ndaruhuye, Dieudonne
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).
Cabrera Becerra, V
Some doubts have been expressed over whether the slowing pace of urbanization suggested by the 1990 census of Mexico was an accurate reflection of changing conditions, or whether it resulted from some intentional or unintended bias. Comparison of data from succeeding censuses indicates that the growth rate of the city of Puebla declined from 6.32% in 1980 to 2.63% in 1990. This work argues that, in Puebla, a trend to deconcentration of the population within the city of Puebla during the 1980s was accompanied by rapid growth in smaller and medium sized nearby cities, resulting in increased overall concentration in Puebla's metropolitan area. The absolute population of the city of Puebla increased from 772,908 in 1980 to 1,007,170 in 1990. The central area of the state of Puebla, which surrounds the city, increased its share of the state population from 51.67% in 1980 to 52.21% in 1990. The number of places with over 5000 inhabitants in the area surrounding the city of Puebla increased from 27 in 1980 to 39 in 1990. Construction of the Puebla-Atlixco highway will undoubtedly attract growth to the area southwest of Puebla. Small cities to the east of Puebla have shown significant growth although their region remains strongly rural. The same process of deconcentration of population in Puebla and concentration in its surrounding metropolitan regions can probably also be detected in patterns of investment of public funds. The trend is likely to continue through the 1990s.
Kim, Youngjin; Li, Sheng; Chekli, Laura; Phuntsho, Sherub; Ghaffour, Noreddine; Leiknes, TorOve; Shon, Ho Kyong
In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55days. The FDFO performance was first investigated in terms of flux decline with various fertilizers draw solution. Flux decline was very severe with all fertilizers due to the absence of aeration and the sticky property of sludge. Flux recovery by physical cleaning varied significantly amongst tested fertilizers which seriously affected biofouling in FDFO via reverse salt flux (RSF). Besides, RSF had a significant impact on nutrient accumulation in the bioreactor. These results indicated that nutrient accumulation negatively influenced the anaerobic activity. To elucidate these phenomena, bacterial and archaeal community structures were analyzed by pyrosequencing. Results showed that bacterial community structure was affected by fertilizer properties with less impact on archaeal community structure, which resulted in a reduction in biogas production and an increase in nitrogen content. Copyright © 2017 Elsevier Ltd. All rights reserved.
In this study, a side-stream anaerobic fertilizer-drawn forward osmosis (FDFO) and ultrafiltration (UF) membrane bioreactor (MBR) hybrid system was proposed and operated for 55 days. The FDFO performance was first investigated in terms of flux decline with various fertilizers draw solution. Flux decline was very severe with all fertilizers due to the absence of aeration and the sticky property of sludge. Flux recovery by physical cleaning varied significantly amongst tested fertilizers which seriously affected biofouling in FDFO via reverse salt flux (RSF). Besides, RSF had a significant impact on nutrient accumulation in the bioreactor. These results indicated that nutrient accumulation negatively influenced the anaerobic activity. To elucidate these phenomena, bacterial and archaeal community structures were analyzed by pyrosequencing. Results showed that bacterial community structure was affected by fertilizer properties with less impact on archaeal community structure, which resulted in a reduction in biogas production and an increase in nitrogen content.
society. However, these two factors do not work on husbands in the same way, demonstrating men’s inflexible attitudes toward gender roles in the family and in society. Son preference exerts a positive impact on American-Chinese fertility and prevents further decline; still, this influence has been diminishing since 1990, as observed in this study.
The agro-climatic conditions in western Kenya present the region as a food surplus area yet people are still reliant on food imports, with the region registering high poverty levels. Depletion of soil fertility and the resulting decline in agricultural productivity in Mbale division has led to many attempts to develop and popularize ...
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.
Williams, Jill; Ibisomi, Latifat; Sartorius, Benn; Kahn, Kathleen; Collinson, Mark; Tollman, Stephen; Garenne, Michel
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.
Williams, Jill; Ibisomi, Latifat; Sartorius, Benn; Kahn, Kathleen; Collinson, Mark; Tollman, Stephen; Garenne, Michel
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
Rantakokko, Merja; Mänty, Minna Regina; Rantanen, Taina
Mobility is important for community independence. With increasing age, underlying pathologies, genetic vulnerabilities, physiological and sensory impairments, and environmental barriers increase the risk for mobility decline. Understanding how mobility declines is paramount to finding ways...... to promote mobility in old age....
Manglos-Weber, Nicolette D; Weinreb, Alexander A
Goode's foundational work on the fertility transition identified own-choice marriage as a factor driving fertility decline, part of a widening repertoire of choice pertaining to marriage and childbearing. Yet research supporting this connection in today's transitional societies is scarce and somewhat contradictory, and it is unclear how other marital traditions, such as consanguineous marriage, shape this relationship. This study evaluates Goode's theorized connection using pooled Demographic and Health Survey data from Turkey, comparing children ever born, use of contraception, and parity progression across four types of marriage: own-choice and arranged marriage; and marriage to a cousin versus an unrelated spouse. Results are largely consistent with the idea that a move towards own-choice marriage reflects a widening repertoire of choice that also leads to fertility decline. However, they also show that hybrid models like own-choice marriage to a cousin tempers these effects.
Wilson, Robert S; Segawa, Eisuke; Buchman, Aron S; Boyle, Patricia A; Hizel, Loren P; Bennett, David A
The study aim was to test the hypothesis that motor function undergoes accelerated decline proximate to death. As part of a longitudinal clinical-pathologic study, 124 older Roman Catholic nuns, priests, and monks completed at least 7 annual clinical evaluations, died, and underwent brain autopsy and uniform neuropathologic examination. Each evaluation included administration of 11 motor tests and 19 cognitive tests from which global measures of motor and cognitive function were derived. The global motor measure (baseline M = 0.82, SD = 0.21) declined a mean 0.024 unit per year (95% confidence interval [CI]: -0.032, -0.016) until a mean of 2.46 years (95% CI: -2.870, -2.108) before death when rate of decline increased nearly fivefold to -0.117 unit per year (95% CI: -0.140, -0.097). The global cognitive measure (baseline M = 0.07, SD = 0.45) declined a mean of 0.027-unit per year (95% CI: -0.041, -0.014) until a mean of 2.76 years (95% CI: -3.157, -2.372) before death when rate of decline increased more than 13-fold to -0.371 unit per year (95% CI: -0.443, -0.306). Onset of terminal motor decline was highly correlated with onset of terminal cognitive decline (r = .94, 95% CI: 0.81, 0.99), but rates of motor and cognitive change were not strongly correlated (preterminal r = .20, 95% CI: -0.05, 0.38; terminal r = .34, 95% CI: 0.03, 0.62). Higher level of plaques and tangles was associated with earlier onset of terminal decline in motor function, but no pathologic measures were associated with rate of preterminal or terminal motor decline. The results demonstrate that motor and cognitive functions both undergo a period of accelerated decline in the last few years of life. 2013 APA, all rights reserved
Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten
Forests of northern ecosystems respond slowly to management activities and the possibilities to increase the growth in a short-term perspective and meet swift increases in society's demand for biomass are small. An exception among the silvicultural measures is fertilization which can be applied...... in combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different...... fertilization regimens, environmental constraints and possibilities in northern forests on mineral soils. Further on we discuss the implications of both extensive and more intensive fertilization in relation to the developing bioeconomy, which encompasses the production and conversion of renewable biological...
... heavy alcohol consumption (> 2 drinks per day), heavy caffeine consumption, and the use of recreational drugs such as marijuana have all been associated with reduced fertility. Therefore, women (and ... alcohol and caffeine use, and avoid smoking and all recreational drugs ...
U.S. Environmental Protection Agency — Amounts of fertilizer P2O5 purchased by states in individual years 2003, 2005, 2007, 2009 and 2011, and the % change in average amounts purchased per year from...
Gade, Elisabeth Juul; Thomsen, Simon Francis; Lindenberg, Svend
of fertility treatments, and the number of successful pregnancies differ significantly between women with unexplained infertility with and without asthma.245 women with unexplained infertility (aged 23-45 years) underwent questionnaires and asthma and allergy testing while undergoing fertility treatment. 96...... women entering the study had either a former doctor's diagnosis of asthma or were diagnosed with asthma when included. After inclusion they were followed for a minimum of 12 months in fertility treatment, until they had a successful pregnancy, stopped treatment, or the observation ended.The likelihood...... pregnancies during fertility treatment, 39.6 versus 60.4% (p=0.002). Increasing age was of negative importance for expected time to pregnancy, especially among asthmatic women (interaction between age and asthma on time to pregnancy, p=0.001). Female asthmatics had a longer time to pregnancy and less often...
Lambertini, Matteo; Del Mastro, Lucia; Pescio, Maria C
In the last years, thanks to the improvement in the prognosis of cancer patients, a growing attention has been given to the fertility issues. International guidelines on fertility preservation in cancer patients recommend that physicians discuss, as early as possible, with all patients...... of reproductive age their risk of infertility from the disease and/or treatment and their interest in having children after cancer, and help with informed fertility preservation decisions. As recommended by the American Society of Clinical Oncology and the European Society for Medical Oncology, sperm...... cryopreservation and embryo/oocyte cryopreservation are standard strategies for fertility preservations in male and female patients, respectively; other strategies (e.g. pharmacological protection of the gonads and gonadal tissue cryopreservation) are considered experimental techniques. However, since then, new...
Description This book contains 19 chapters that discuss theoretical and applied andrology for domestic, zoo and wild animals. Topics include semen and its constituents; sperm production and harvest; determinants of sperm morphology; sperm preparation for fertilization; practical aspects of semen
U.S. Environmental Protection Agency — Amounts of fertilizer nitrogen (N) purchased by states in individual years 2003, 2005, 2007, 2009 and 2011, and the % change in average amounts purchased per year...
Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia
Biochar produced in cost-efficient flame curtain kilns (Kon-Tiki) was nutrient enriched either with cow urine or with dissolved mineral (NPK) fertilizer to produce biochar-based fertilizers containing between 60-100 kg N, 5-60 kg P2O5 and 60-100 kg K2O, respectively, per ton of biochar. In 21 field trials nutrient-enriched biochars were applied at rates of 0.5 to 2 t ha-1 into the root zone of 13 different annual and perennial crops. Treatments combining biochar, compost and organic or chemical fertilizer were evaluated; control treatments contained the same amounts of nutrients but without biochar. All nutrient-enriched biochar substrates improved yields compared to their respective no-biochar controls. Biochar enriched with dissolved NPK produced on average 20% ± 5.1% (N=4) higher yields than standard NPK fertilization without biochar. Cow urine-enriched biochar blended with compost resulted on average in 123% ± 76.7% (N=13) higher yields compared to the organic farmer practice with cow urine-blended compost and outcompeted NPK-enriched biochar (same nutrient dose) by 103% ± 12.4% (N=4) on average. 21 field trials robustly revealed that low-dosage root zone application of organic biochar-based fertilizers caused substantial yield increases in rather fertile silt loam soils compared to traditional organic fertilization and to mineral NPK- or NPK-biochar fertilization. This can likely be explained by the nutrient carrier effect of biochar causing a slow nutrient release behavior, more balanced nutrient fluxes and reduced nutrient losses especially when liquid organic nutrients are used for the biochar enrichment. The results promise new pathways for optimizing organic farming and improving on-farm nutrient cycling.
Utt, Matthew D
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.
Damario, Mark A
Fertility rates have been declining in most Western nations over the past several decades, although it is not entirely clear if an increased rate of infertility substantially contributes to this. As compared to other species, the reproductive efficiency of humans is relatively low. Factors related to fertility include age, exposure to sexually transmitted diseases, frequency of intercourse, coital timing, as well as diet and lifestyle habits. Infertility is considered a disease due to its major disruption of major organ systems and life functions. An infertility evaluation is recommended after 12 months or more of regular, unprotected intercourse and may be considered after 6 months for those female patients over the age of 35 or with other known abnormalities. A proper infertility evaluation is a comprehensive examination of possibly identifiable infertility factors of both female and male partners, lending itself to the most appropriate and potentially effective treatment.
Sanderson, W C
This paper deals with three aspects of the decline in the fertility of white women in the United States from 1800 to 1920. The first concerns the portion of the secular decline in the total fertility rate which was due to changes in marriage rates and the portion due to decreases in marital fertility rates. The second concerns the fraction of couples in the nineteenth century who acted effectively to reduce their fertility and the third deals with the importance of abortion as a family-limiting practice among white couples in the nineteenth century.
Klinger, Christie R; Lau, Jennifer A; Heath, Katy D
Anthropogenic changes can influence mutualism evolution; however, the genomic regions underpinning mutualism that are most affected by environmental change are generally unknown, even in well-studied model mutualisms like the interaction between legumes and their nitrogen (N)-fixing rhizobia. Such genomic information can shed light on the agents and targets of selection maintaining cooperation in nature. We recently demonstrated that N-fertilization has caused an evolutionary decline in mutualistic partner quality in the rhizobia that form symbiosis with clover. Here, population genomic analyses of N-fertilized versus control rhizobium populations indicate that evolutionary differentiation at a key symbiosis gene region on the symbiotic plasmid (pSym) contributes to partner quality decline. Moreover, patterns of genetic variation at selected loci were consistent with recent positive selection within N-fertilized environments, suggesting that N-rich environments might select for less beneficial rhizobia. By studying the molecular population genomics of a natural bacterial population within a long-term ecological field experiment, we find that: (i) the N environment is indeed a potent selective force mediating mutualism evolution in this symbiosis, (ii) natural variation in rhizobium partner quality is mediated in part by key symbiosis genes on the symbiotic plasmid, and (iii) differentiation at selected genes occurred in the context of otherwise recombining genomes, resembling eukaryotic models of adaptation. © 2016 The Author(s).
Baron, J.; Advani, S. M.; Allen, J.; Boot, C.; Denef, K.; Denning, S.; Hall, E.; Moore, J. C.; Reuth, H.; Ryan, M. G.; Shaw, E.
Long-term field experiments can reveal changes in ecosystem processes that may not be evident in short-term studies. Short-term measurements or experiments may have narrower objectives or unrealistic treatments in order to see a change, whereas long-term studies can reveal complex interactions that take longer to manifest. We report results from a long-term experiment (1996 to present) in subalpine forests to simulate the consequences of sustained atmospheric nitrogen (N) deposition. Loch Vale watershed in Rocky Mountain National Park, the location of the experiment, has received an order of magnitude greater atmospheric N deposition than estimated background since mid-20th Century. Augmenting that, in 1996 we began adding 25 kg NH4NO3 ha-1 yr-1 to three 30m x 30m old-growth Engelmann spruce and subalpine fir plots. Treated stands were matched by nearby controls. N addition caused rapid leaching of nitrate and cations from soils, and increased N mineralization and nitrification rates. These observations in the fertilized plots have been sustained over time. Soluble aluminum concentrations do not differ significantly between fertilized and control plots, but treated soils are now markedly more acidic (pH of 4.7) than original soil and controls (pH of 5.1); further acidification might increase aluminum leaching. Effects on soil carbon were complex, mediated by reductions in total microbial biomass, decreases in arbuscular mychorrizal and saprotropic fungi, and increased potential rates of N enzyme degrading activities. Initial soil C:N of 24 was lower than similar soils in low N deposition stands (C:N of 36). The C:N declined to 22 with treatment. Fertilized plots lost 11% soil C, but the mechanism is unclear. We did not measure changes in C inputs from litter, microbial biomass, or plant uptake, but there was no change in summer CO2 flux, measured in 2003, 2004, and 2014. Leaching of DOC from fertilized plots was elevated throughout the experiment, providing one
Bellido, Héctor; Marcén, Miriam
This paper explores the effect of divorce law reforms on fertility. By modifying the value of marriage, the introduction of divorce law reforms may impact fertility decisions. To identify the effects of those reforms on fertility, we use a quasi-experiment exploiting the legislative history of divorce liberalization across Europe. Results suggest that divorce law reforms have a negative and permanent effect on fertility. Divorce reforms decreased the Total Fertility Rate by about 0.2. The mag...
Rickels, Wilfried; Rehdanz, Katrin; Oschlies, Andreas
Diminishing emission budgets and increasing risks of catastrophic damages from climate change require analyses of rapid response options including geoengineering options such as ocean iron fertilization (OIF). To decide whether or not OIF might be such an option an assessment of its potential as an abatement option as well as its possible side effects is required. To explore the potential of OIF knowledge on the change of carbon stocks over time is needed. However, economic aspects including ...
Maro, G.P.; Mrema, J.P.; Msanya, B.M.; Janssen, B.H.; Teri, J.M.
The aim of this study was to develop a simple and quantitative system for coffee yield estimation and nutrient input advice, so as to address the problem of declining annual coffee production in Tanzania (particularly in its Northern coffee zone), which is related to declining soil fertility. The
The common bean is an important food and cash crop in Eastern, Central and Southern Africa. It provides food for more than 100 million people and is a critical source of income for rural households. Common bean yields, however, have declined in the last ten years. This decline is the result of poor soil fertility and nutrient ...
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.
Juan F. Gamella
Full Text Available Background: Most Romani groups in Europe have experienced a decline in childhood mortality during recent decades. These crucial transformations are rarely addressed in research or public policy. Objective: This paper analyzes the timing and structure of the decline of childhood mortality among the Gitano people of Spain. Methods: The paper is based on the family and genealogy reconstitution of the Gitano population of 22 contiguous localities in Southern Spain. Registry data from over 19,100 people and 3,501 reconstituted families was included in a dense genealogical grid ranging over 150 years. From this database we produced annual time series of infant and child mortality and of the registered causes of death from 1871 to 2005. Results: The analyzed data shows a rapid decline in infant and child mortality from about 1949 to 1970. The onset of the definitive decline occurred in the late 1940s and early 1950s. Child mortality was higher in the pre-transitional period and started to decline earlier, although it took longer to converge with majority rates. The mortality transition in the Gitano minority paralleled that of the dominant majority, but with important delays and higher mortality rates. The causes of death show the deprivation suffered by Gitano people. Conclusions: The childhood mortality decline facilitated the most important changes experienced recently by the Gitano minority, including its fertility transition and the transformation of Gitanos' gender and family systems. Contribution: This is one of the first historical reconstructions of the mortality transition of a Romani population.
Jalil, Wan Aznie Fatihah Wan Abd; Sharif, Shamshuritawati
A fertility rate is a measure of the average number of children a woman will have during her childbearing years. Malaysia is now facing a population crisis and the fertility rate continues to decline. This situation will have implications for the age structure of the population where percentages of senior citizens are higher than percentages of people aged below 5 years old. Malaysia is expected to reach aging population status by the year 2035. As the aging population has a very long average life expectancy, the government needs to spend a lot on medical costs for senior citizens and need to increase budgets for pensions. The government may be required to increase tax revenues to support the growing older population. The falling fertility rate requires proper control by relevant authorities, especially through planning and implementation of strategic and effective measures. Hence, this paper aims to develop a fertility index using Shannon's entropy method. The results show that Selangor, Johor, and Sarawak are among the states with the highest values of the fertility index. On the other end of the spectrum, Terengganu, W.P. Labuan, and Perlis are ranked in the last positions according to the fertility index. The information generated from the results in this study can be used as a primary source for the government to design appropriate policies to mitigate dwindling fertility rates among Malaysian women.
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.
This year marks a centenary of the synthetic fertilizer industry. German chemists, Fritz Haber and Carl Bosch, in 1909 demonstrated their industrial process for the manufacture of ammonia. The achievement won them accolades including Nobel Prizes. The output of their Haber-Bosch process can be used for either peace or war, agriculture or munitions, and the rapid adoption by Germany of this industrial process is credited with prolonging WW1. Most of the synthetic nitrogenous fertilizer of the...
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.
Rabbitt, Patrick; Lunn, Mary; Pendleton, Neil; Yardefagar, Ghasem
To test whether different terminal pathologies are associated with different rates of age-related decline in fluid and crystallized mental abilities and whether pathology-associated declines are accelerated by age. During a 20-year longitudinal study, 6203 participants were quadrennially assessed on the Heim's (Heim, A 1970) The AH4 series of intelligence tests Slough, U.K.: NEP) AH4-1 and AH4-2 tests of fluid intelligence and on the Raven's (Raven, J. C. 1965) The Mill Hill Vocabulary Scale London: H.K. Lewis) Mill Hill A and B tests of recognition and production vocabulary. Dates and proximate causes of death were logged for 2499 participants. Multilevel modelling compared rates of decline after effects of sex, demographics, and practice were taken into consideration. Rates of cognitive decline markedly differed across pathologies, being most rapid for dementias and infections, slower for malignancies, and most prolonged for cardiovascular conditions. Pathologies were associated with faster declines in older individuals. After sex, age, and demographics have also been considered, different terminal pathologies are associated with markedly different rates of decline. Age accelerates pathology-related decline. This raises the further question as to whether any, or how much of, age-related cognitive decline is brought about by other causes than an increasing burden of pathologies.
Barnett, Rebecca; Banks, Nicole; Decherney, Alan H
Endometriosis is common, affecting 5% to 10% of reproductive age women. Nearly half of women with surgical evidence of endometriosis fail to achieve spontaneous pregnancy. Surgical treatment of endometriosis can be detrimental to ovarian reserve. In the absence of surgical intervention, ovarian reserve may still be negatively impacted over time. Fertility preservation was developed for women requiring gonadotoxic treatments. Improved methods have led to greater consideration of offering these services to women with other disease processes that threaten ovarian reserve. This chapter will present the debate regarding use of fertility preservation in management of endometriosis, and outline the need for further studies.
Zhi Hong Zhang
Full Text Available Background: Previous researches about the effect of smoking on semen quality are contradictory, and the mechanism behind the harmful effect of smoking on semen quality still remains unclear until today. Objective: The objectives of this study are evaluation of the relationship between smoking and fertility, investigation of the effects of cigarette smoking on sperm parameters and detection of presence of leukocytes within the semen of idiopathic infertile men from Northeastern China. Materials and Methods: A retrospective study of 1512 infertile patients who visited affiliated hospitals of Jilin University from 2007-2010 were enrolled in this study. Patients were assigned into one non-smoking and one smoking group which was divided into mild, moderate and heavy subgroups. Sperm parameters (including leukocytes and sperm morphology analysis were performed using standard techniques. Results: Compared with non-smokers, smokers had a significant decrease in semen volumes (p=0.006, rapid progressive motility (p=0.002 and sperm viability (p=0.019; moreover, smokers had a significant increase in the levels of immotile sperms (p=0.005 and semen leukocytes (p=0.002; pH and sperm concentration were not statistically significant (p=0.789 and p=0.297 respectively. Sperm motion parameters were all lower in the smokers except for beat-cross frequency (Hz (BCF. Further, the percentage of normal morphology sperm was decreased significantly in smokers (p=0.003, the sperm morphology was worse with increasing degree of smoking. Conclusion: These findings suggest that smoking leads to a significant decline in semen quality and higher levels of leukocytes, thus smoking may affects the fertilization efficiency.
Luo, Jinping [Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160 (United States); McGinnis, Lynda K. [Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160 (United States); Carlton, Carol [Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160 (United States); Beggs, Hilary E. [Department of Ophthalmology, University of California, San Francisco, CA (United States); Kinsey, William H., E-mail: firstname.lastname@example.org [Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS 66160 (United States)
Highlights: • PTK2b is expressed in oocytes and is activated following fertilization. • PTK2b suppression in oocytes prevents fertilization, but not parthenogenetic activation. • PTK2b suppression prevents the oocyte from fusing with or incorporating bound sperm. • PTK2b suppressed oocytes that fail to fertilize do not exhibit calcium oscillations. - Abstract: Fertilization triggers rapid changes in intracellular free calcium that serve to activate multiple signaling events critical to the initiation of successful development. Among the pathways downstream of the fertilization-induced calcium transient is the calcium-calmodulin dependent protein tyrosine kinase PTK2b or PYK2 kinase. PTK2b plays an important role in fertilization of the zebrafish oocyte and the objective of the present study was to establish whether PTK2b also functions in mammalian fertilization. PTK2b was activated during the first few hours after fertilization of the mouse oocyte during the period when anaphase resumption was underway and prior to the pronuclear stage. Suppression of PTK2b kinase activity in oocytes blocked sperm incorporation and egg activation although sperm-oocyte binding was not affected. Oocytes that failed to incorporate sperm after inhibitor treatment showed no evidence of a calcium transient and no evidence of anaphase resumption suggesting that egg activation did not occur. The results indicate that PTK2b functions during the sperm-egg fusion process or during the physical incorporation of sperm into the egg cytoplasm and is therefore critical for successful development.
The Hooded Vulture Necrosyrtes monachus is not currently listed on the IUCN Red List of threatened species, yet recent email discussions amongst a group of African raptor experts suggests this species may be in rapid decline. Information was solicited from raptor experts, as well as from published and unpublished ...
Islam, M N; Abedin, S
Data from the 1983, 1986, 1989, and 1991 Bangladesh Contraceptive Prevalence Survey are used to examine the trends in marriage patterns and to evaluate the impact of contraception and marriage on fertility. Coale's nuptiality model is used to analyze the pace of marriage, the proportion married, and the marriage age and the impact on fertility. Bongaarts' model is used to evaluate the contribution of marriage and contraception to the total fertility rate (TFR). Findings indicate that TFR declined from 6.08 children/woman in 1983 to 4.63 children/woman in 1991: a decline of 24% in 8 years. Total marital fertility declined by 20.6% in 8 years. The contraceptive prevalence rate increased about 21% in 8 years to 39.9%. The proportions of single women aged 15-19 years and 20-24 years increased greatly to 46.7% and 12.3%, respectively, in 1991. Marriage has remained universal. The tempo of marriage increased about 24% in 8 years to 0.58 in 1991. Over time, the tempo of marriage slowed, and the marriage age span increased and did so with greater intensity during 1989-91. The marriage age span increased from 18.80 years to 23.20 years during 1983-91. The age of spinsterhood increased to 35 years. Findings from Bongaarts' and Coale's models show that reductions in total fertility were much more a result of changes in marital reproductive behavior and the use of contraception than the change in the marriage pattern. These two indices reduced fertility by 32.8% in 1983 and 51.5% in 1991.
We increasingly understand the causes of urban population decline: these can be, among others, processes of deindustrialisation, decreasing fertility or the succession of a city through the stages of urban life as the city matures. However, we are still insufficiently able to explain why differences
After the pollen grain reaches the stigma through outsourcedagents (pollinators), the next step before fertilization is to selectthe right type of pollen. Similar to a marriage in humanbeings, flowering plants also have evolved elaborate screeningprocess to select the right pollen grains and to reject thewrong ones. Even after ...
passive. However, when the pollen grain is from a very closely related species, the pollen may still have all the matching keys to the locks of the pistil. Such a pollen grain may germinate and reach the ovule. Some of them may even achieve fertilization but their embryos generally abort, thus preventing the formation of.
Orgebin-Crist, Marie-Claire; And Others
In this report, emphasis is placed on major research developments in the reproductive sciences, their impact on the health of individuals as well as on that of society, and on current trends that may provide new opportunities for future research in fertility and infertility. In the first section, major developments in the reproductive sciences are…
The number of children per woman is between 6 and 7 children in Black Africa. Infertility and poor fertility existing in certain regions of Africa only appear in results concerning central Africa. 6-10% of births occur in women between the ages of 40 and 50. It must be noted that the goal of the majority of societies in Black Africa is to have numerous descendants. Factors of fertility in Africa examined are: precocious marriage, a long period of exposure to the risk of pregnancy, birth spacing and pathological infertility. The paper also discusses modern contraception and birth control, the improvement of sanitation conditions as part of the battle against infertility and infant mortality, combating infertility, decreasing infant mortality and governmental attitudes toward fertility control. Despite the efforts of several private and governmental agencies to promote family planning, progress in Africa has been modest. In the majority of Black African countries, women do not have access to contraception. In rural areas, the absence of an administrative infrastructure prevents diffusion of information and access to contraception. Improving general health conditions has 2 consequences on fertility: it reduces infertility due to diseases that cause sterility and it reduces infant mortality which affects birth intervals. So far birth control has only been successful among the very educated women. However, a great potential for more users exists.
French wines, differentiated by geographic origin, served for many decades as a basis for the French success in the British wine market. However in the early 1990s, market share began to decline. This article explores the values that market participants placed on labelling information on French...... wines in Britain in 1994. Results from a parametric hedonic approach indicate that both the lack of a consistently positive valuation of varietal wines and the low valuation of wines with geographical appellation help to explain the overall decline of France's role in the British wine market...
Full Text Available ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...
Full Text Available ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ... health care products or services, or control the information found on external websites. The Hill Foundation is ...
Full Text Available ... Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord ... a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. Rowles, MS, ...
... and what you can do to improve your fertility. By Mayo Clinic Staff Do your sperm pass ... understanding the various factors that can affect male fertility — then consider steps to help your sperm become ...
... Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord ... a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. Rowles, MS, ...
Fertilizers and soil amendments can be derived from raw materials, composts and other organic matter, and wastes, such as sewage sludge and certain industrial wastes. Overuse of fertilizers can result in contamination of surface water and groundwater.
Full Text Available This paper presents an empirical analysis of the relationship between fertility and a direct measure of poverty for Indonesia, a country, which has experienced unprecedented economic growth and sharp fertility declines over recent decades. It focuses on illustrating the sensitivity of the effect of fertility on household consumption with respect to the equivalence scale by applying the propensity score matching method. The analysis suggests that a newborn child decreases household consumption per person by 20 percent within four years. When the estimates of equivalence scales implied by the Indonesian sample are applied, the effect of a child on household consumption is still negative, but the magnitudes are in the range from 20 to 65 percent of that found with the per-capita expenditure as a measure of consumption. Therefore, it is suggested that the analysis based on the conventional measure of poverty is likely to exaggerate the effect of fertility on poverty at least because of the neglect of the proper equivalence scale.
Martin, L G
Slowing the growth of the 100 million plus population of Bangladesh remains a major challenge. Fertility and mortality declined only slightly during the 1970s and the population continues to grow at an annual rate of over 2.5%, implying a doubling time of about 25 years. This article briefly reviews the theoretical link between education and fertility, the educational situation in Bangladesh, and the projects's design and its effects as evaluated by a US Agency for International Development (AID) International Science and Technology Institute team. Nearly all women are married by age 25 in Bangladesh, but more educated women marry later than the less educatted ones. Age at marriage has the greatest effect of all the variables on children ever born; given the association between age at marriage and education, it can be argued that education does indeed affect fertility. In 1982, USAID began funding a pilot project by the Bangladesh Association for Community Education to provide secondary scholarships for girls in Chandpur District. Only 30% of the secondary school completers had married by the time of the survey, in comparison to 76% of the secondary dropouts, 77% of the primary school completers, and 66% of those with no school. Clearly, there is much to be done in reducing population pressure and raising the standard of living in Bangladesh, and raising the status of women through education could be a valuable component in such efforts.
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.
Radovich, Emma; El-Shitany, Atef; Sholkamy, Hania; Benova, Lenka
In 2014, Egypt's Demographic and Health Survey (EDHS) documented an increase in the total fertility rate (TFR) to 3.5, up from a low of 3.0 recorded by the 2008 EDHS. The increase has been anecdotally attributed to the social upheaval following Egypt's January 2011 revolution, but little is known about when fertility first began to increase and among which sub-groups of women. Using birth histories from seven rounds of EDHS (1992-2014), this study reconstructed fertility rates for single years from 1990-2013 and examined patterns of childbearing in five-year birth cohorts of women. We found that the decline in fertility reversed in 2007, earlier than postulated, plateaued and then increased again in 2013. The increase in TFR coincided with a convergence of fertility rates across education levels, and there is evidence of a shift toward childbearing at younger ages among more educated women, which may be inflating period measures of fertility.
David R. DeWalle; Jeffrey S. Tepp; Bryan R. Swistock; Pamela J. Edwards; William E. Sharpe; Mary Beth Adams; James N. Kochenderfer
Use of chemical element content of tree rings to detect soil acid or base changes was tested at 13 sites of former forest fertilization trials in the eastern United States and Canada. Ammonium sulfate or nitrogen fertilization was the typical acidification treatment, while lime added with or without other fertilizer was the typical base treatment. Molar ratios of...
Ding, Nengfei; Li, Weidong; Liu, Chen; Fu, Qinglin; Guo, Bin; Li, Hua; Li, Ningyu; Lin, Yicheng
The aim of this study was to propose a feasible treatment of kitasamycin manufacturing waste by examining extractable kitasamycin and evaluating its compost maturity during the composting of waste with different ratios of dairy manure and sawdust over a 40-day period (volume/volume/volume; M1, 0/80/20; M2, 10/70/20; and M3, 30/50/20). During composting, the concentration of extractable kitasamycin in kitasamycin-contaminated composts declined rapidly, and was undetectable in M2 within 15 days. M2 also achieved the highest fertility compost, which was characterised by the following final parameters: electrical conductivity, 2.34 dS cm(-1); pH, 8.15; total C/N, 22.2; water-soluble NH4(+), P, and K, 0.37, 3.43, and 1.05 g kg(-1), respectively; and plant germination index values, 92%. Furthermore, DGGE analysis showed a dramatic increase in the diversity of bacterial species during composting. In contrast, a high concentration (121 mg kg(-1)) of extractable kitasamycin still remained in the M3 compost, which exerted an inhibitory effect on the composting, resulting in reduced bacterial diversity, high values of electrical conductivity and water-soluble NH4(+), a low C/N ratio, and a low plant germination index value. Furthermore, 3.86 log (CFU g(-1)) kitasamycin-resistant bacteria were still present on day 40, indicating the biological degradation contributed to the decline of extractable kitasamycin. Copyright © 2014 Elsevier Ltd. All rights reserved.
Full Text Available ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ...
... website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open ... Diagnosed with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation ...
Full Text Available ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ...
Full Text Available ... issues for young girls undergoing fertility preservation? Can male children bank sperm to preserve their fertility? What ... fertility preservation options for young boys and adolescent males? What are the fertility preservation options for prepubertal ...
van den Berg, G.B.; Smolders, C.A.
When a membrane filtration process such as ultrafiltration is used a flux- and yield-decline can be observed. The causes are i) concentration polarization (i.e. accumulation of retained solutes, reversibly and immediately occurring) and ii) fouling phenomena such as adsorption, pore-blocking and
thrips; ants; butterflies; moths; bats ; and hummingbirds and other birds. 2 Berenbaum, M.R., University of Illinois, Statement before the... vampire mite (Varroa destructor) and the tracheal mite (Acarapis woodi), and also colony declines due to the pathogen Paenibacillus larvae.12 Other reasons
The paper discusses the concept of resource efficiency in the economy as a whole. This implies some unfoldings of the simple definition of efficiency as human satisfaction over throughput of resources. It is suggested, that the efficiency of the economic systems is declining in the countries...
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...
Audirac, Ivonne; Cunningham-Sabot, Emmanuèle; Fol, Sylvie; Moraes, Sergio Torres
Suburban shrinkage, understood as a degenerative urban process stemming from the demise of the Fordist mode of urbanism, is generally manifested in a decline in population, industry and employment. It is also intimately linked to the global restructuring of industrial organization associated with the rise of the post-Fordist mode of urbanism and, more recently, the thrust of Asian industrialization. Framed in the discourse of industrial urbanism, this article examines the first ring of industrial suburbs that developed around large cities in their most rapid Fordist urbanization phase. These industrial suburbs, although they were formed at different times, are today experiencing specific mutations and undergoing profound restructuring on account of their particular spatial position between the central area and the expanding peripheries of the post-Fordist metropolis. This article describes and compares suburban decline in two European cities (Glasgow and Paris) and two Latin American Cities (São Paulo, Brazil and Guadalajara, Mexico), as different instances of places asymmetrically and fragmentarily integrated into the geography of globalization.
Jones, James Holland; Tuljapurkar, Shripad
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.
Full Text Available Background: More than downplayed, the role of men in the demographic analysis of reproduction has been entirely neglected. However, male fertility can be an important issue for exploring how economic and employment uncertainties relate to fertility and family dynamics. Objective: This paper intends to study fertility variations over time, relying solely on data referring to father's socio-demographic characteristics; in particular, their age, education level, and employment status. Methods: We use a combination of Labor Force Survey and Demographic Statistics data on population and Vital Statistics on births to estimate male fertility indicators and fertility differentials by education level and employment status, for the period 1992-2011 in Greece. In addition, over-time developments in male TFR are separated into structural (education-specific and employment-specific distributions and behavioral (fertility, per se changes. Results: We find that the male fertility level is declining, the fertility pattern is moving into higher ages, and the reproduction period for men is getting shorter. From 1992 up to 2008, changes in male fertility were mostly driven by behavioral rather than compositional factors. However, the decline of male fertility over the period of economic recession (2008-2011 is largely attributed to the continuous decrease in the proportions of employed men. Conclusions: The study suggests that male fertility merits further exploration. In particular, years of economic downturn and countries where household living standards are mostly associated with male employment, a father's employability is likely to emerge as an increasingly important factor of fertility outcomes.
Prager, Case M; Naeem, Shahid; Boelman, Natalie T; Eitel, Jan U H; Greaves, Heather E; Heskel, Mary A; Magney, Troy S; Menge, Duncan N L; Vierling, Lee A; Griffin, Kevin L
Rapid environmental change at high latitudes is predicted to greatly alter the diversity, structure, and function of plant communities, resulting in changes in the pools and fluxes of nutrients. In Arctic tundra, increased nitrogen (N) and phosphorus (P) availability accompanying warming is known to impact plant diversity and ecosystem function; however, to date, most studies examining Arctic nutrient enrichment focus on the impact of relatively large (>25x estimated naturally occurring N enrichment) doses of nutrients on plant community composition and net primary productivity. To understand the impacts of Arctic nutrient enrichment, we examined plant community composition and the capacity for ecosystem function (net ecosystem exchange, ecosystem respiration, and gross primary production) across a gradient of experimental N and P addition expected to more closely approximate warming-induced fertilization. In addition, we compared our measured ecosystem CO 2 flux data to a widely used Arctic ecosystem exchange model to investigate the ability to predict the capacity for CO 2 exchange with nutrient addition. We observed declines in abundance-weighted plant diversity at low levels of nutrient enrichment, but species richness and the capacity for ecosystem carbon uptake did not change until the highest level of fertilization. When we compared our measured data to the model, we found that the model explained roughly 30%-50% of the variance in the observed data, depending on the flux variable, and the relationship weakened at high levels of enrichment. Our results suggest that while a relatively small amount of nutrient enrichment impacts plant diversity, only relatively large levels of fertilization-over an order of magnitude or more than warming-induced rates-significantly alter the capacity for tundra CO 2 exchange. Overall, our findings highlight the value of measuring and modeling the impacts of a nutrient enrichment gradient, as warming-related nutrient
Morley, James F; Xie, Sharon X; Hurtig, Howard I; Stern, Matthew B; Colcher, Amy; Horn, Stacy; Dahodwala, Nabila; Duda, John E; Weintraub, Daniel; Chen-Plotkin, Alice S; Van Deerlin, Vivianna; Falcone, Dana; Siderowf, Andrew
The role of genetic factors in cognitive decline associated with Parkinson's disease (PD) is unclear. We examined whether variations in apolipoprotein E (APOE), microtubule-associated protein tau (MAPT), or catechol-O-methytransferase (COMT) genotypes are associated with cognitive decline in PD. We performed a prospective cohort study of 212 patients with a clinical diagnosis of PD. The primary outcome was change in Mattis Dementia Rating Scale version 2 score. Linear mixed-effects models and survival analysis were used to test for associations between genotypes and change in cognitive function over time. The ε4 allele of APOE was associated with more rapid decline (loss of 2.9; 95% confidence interval [CI]: 1.7-4.1) of more points per year; P disease stages. Carrying at least one APOE ε4 allele is associated with more rapid cognitive decline in PD, supporting the idea of a component of shared etiology between PD dementia and Alzheimer's disease. Clinically, these results suggest that genotyping can provide information about the risk of future cognitive decline for PD patients. Copyright © 2012 Movement Disorder Society.
Full Text Available Across developed countries, cohorts of women born after World War II have seen a shift of childbearing towards later ages and a concomitant decline in fertility level. We study this shift using the notions of fertility postponement (fertility decline at younger ages and subsequent recuperation (a compensatory fertility increase at higher reproductive ages. We apply order-specific data and extend and elaborate on two broad approaches to this process: 1 a basic benchmark model extensively used by Tomas Frejka and his colleagues and 2 a relational model proposed by Ron Lesthaeghe (2001. Our work focuses especially on three predominantly German-speaking countries, Austria, Germany and Switzerland, and compares them with selected European countries and the United States. We illustrate the usefulness of these two approaches for constructing projection scenarios of completed cohort fertility among women of reproductive age. Using three key indicators of the postponement transition – initial fertility level, absolute fertility decline at younger ages, and the relative degree of fertility “recuperation” at older ages – we demonstrate that each of these components is salient for explaining contemporary cross-country differences in cohort fertility. Recuperation is especially important, but is also clearly patterned by birth order: whereas all the countries analysed have experienced a vigorous recovery of delayed first births, pronounced differentials are observed with regard to the recuperation of second and particularly of third and later births. In line with the differentials observed, projected values of completed fertility in five European countries vary widely for the cohorts born in the early 1980s, ranging from 1.3 in the lowest scenario for Spain to over 1.8 in the highest scenario for the Czech Republic.
McCord, Gordon C; Conley, Dalton; Sachs, Jeffrey D
The broad determinants of fertility are thought to be reasonably well identified by demographers, though the detailed quantitative drivers of fertility levels and changes are less well understood. This paper uses a novel ecological index of malaria transmission to study the effect of child mortality on fertility. We find that temporal variation in the ecology of the disease is well-correlated to mortality, and pernicious malaria conditions lead to higher fertility rates. We then argue that most of this effect occurs through child mortality, and estimate the effect of child mortality changes on fertility. Our findings add to the literature on disease and fertility, and contribute to the suggestive evidence that child mortality reductions have a causal effect on fertility changes. Copyright Â© 2016 Elsevier B.V. All rights reserved.
Description This book contains 19 chapters that discuss theoretical and applied andrology for domestic, zoo and wild animals. Topics include semen and its constituents; sperm production and harvest; determinants of sperm morphology; sperm preparation for fertilization; practical aspects of semen cryopreservation; evaluation of semen in the andrology laboratory; genetic aspects of male reproduction; emerging techniques and future development of semen evaluation and handling and applied androlo...
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.
Olsen, R J; Farkas, G
This paper applies the waiting-time regression methods of Olsen and Wolpin (1983) to an analysis of fertility. A utility maximizing model is set up and used to provide some guidance for an empirical analysis. The data are from an experimental guaranteed job program, the Youth Incentive Entitlement Pilot Project, aimed at young women 16 to 20 years old, from poverty-level families, and not yet high school graduates. The waiting-time regression method of estimation permits the youth in question to be used as her own control revealing how eligibility for the jobs program changes the durations of periods between live-birth conceptions. 3890 women surveyed had 1 birth, 429 had 2, 112 had 3, 26 had 4, and 7 had 5. Without this person specific control described here, the most important factors affecting fertility are number of siblings (negative effect), labor market attachment by parents, especially the father, and the presence of the natural father. With the person specific control, the results predicted from economic theory do emerge: even adolescent and young women consider the economic consequences of fertility reflected in effects of fertility when wages are high in favor of fertility with lower wages. Post program effects (taking place after youths lose eligibility for the program) are a rather rapid making up for foregone fertility, reducing likelihood of net reductions of total fertility.
Saling, P M
A review of sperm antigens involved in fertilization includes a description of sperm differentiation, seminal fluid components that coat sperm, sperm antigens involved in binding to the zona pellucida (ZP), antigens involved in the acrosome reaction, in zona pellucida penetration, and those active in fusion with the ova membrane. Sperm antigens are located in certain domains of the cell, and they are altered during capacitation and passage through the female tract. Caltrin and acrosome-stabilizing factor are applied by seminal fluid. At least 2 antigens have been studied that occur in sterile women, although one cross reacts with milk proteins. Some antigens active in ZP binding are trypsin, proacrosin, acrosin, PH-20 from guinea pigs, and rabbit sperm autoantigen I. Antigens involved in the acrosome reaction, such as M42, are likely to cross react with other body proteins that also entail exocytosis. A mouse antigen involved in ZP penetration, MS 207 is well characterized. PH-30 from guinea pigs and M29 from mouse participate in sperm-egg membrane fusion, as does fertilization antigen I from human and mouse sperm which is know to cause infertility. Oddly, patients' sera react with polymers but not monomers of this antigen. Studies with antisperm antibodies suggest that it will not be necessary to agglutinate all sperm to block fertility, only to inhibit a single sperm epitope and function. It will probably be feasible to inhibit multiple successive events, and possibly to induce temporary immunity.
Full Text Available Much research has been conducted in the field of utilising the media - television and radio in particular - to promote particular public health messages. However, a burgeoning canon has examined how mass media can play a role in affecting change in fertility preferences and outcomes. In this paper we review these researches which have primarily focussed upon higher fertility settings. The impact of mass media presentation of families and children in low fertility settings has not yet been subject to rigorous sociological investigation so its impact can not be accurately inferred. However, given the pervasive nature of mass media and celebrity culture, we suggest that this is an important avenue for future research. We conclude that television plays a multi-faceted role in shaping individuals decision-making procedures concerning both demographic events and public health interactions. To illustrate this, we present a model which demonstrates a sliding scale of intent - but not impact - of various genres in order to understand the actual role of the media in shaping attitudes towards family size - either explicitly in terms of edutainment or implicitly as a forms of normalization.
With the huge intensification of agriculture and the increasing awareness to human health and natural resources sustainability, there was a shift towards the development of environmental friendly N application approaches that support sustainable use of land and sustain food production. The effectiveness of such approaches depends on their ability to synchronize plant nitrogen demand with its supply and the ability to apply favored compositions and dosages of N-species. They are also influenced by farming scale and its sophistication, and include the following key concepts: (i) Improved application modes such as split or localized ("depot") application; (ii) use of bio-amendments like nitrification and urease inhibitors and combinations of (i) and (ii); (iii) use of controlled and slow release fertilizers; (iv) Fertigation-fertilization via irrigation systems including fully automated and controlled systems; and (v) precision fertilization in large scale farming systems. The paper describes the approaches and their action mechanisms and examines their agronomic and environmental significance. The relevance of the approaches for different farming scales, levels of agronomic intensification and agro-technical sophistication is examined as well.
Peterson, Brennan D; Pirritano, Matthew; Tucker, Laura; Lampic, Claudia
In the USA, the postponement of childbearing reflects contemporary social norms of delaying marriage, pursing educational goals and securing economic stability prior to attempting conception. Although university students are more likely to delay childbearing, it is unclear to what extent they are aware of age-related fertility decline. The current study is the first of its kind to assess fertility awareness and parenting attitudes of American undergraduate university students. Two-hundred forty-six randomly selected undergraduate university students (138 females and 108 males) completed an online self-report survey adapted from the Swedish Fertility Awareness Questionnaire. Students were evenly distributed between the freshman, sophomore, junior and senior classes with a mean age of 20.4 years. Participants wanted to have their first and last child within the window of a woman's fertility. However, participants demonstrated a lack of fertility awareness by vastly overestimating the age at which women experience declines in fertility, the likelihood of pregnancy following unprotected intercourse and the chances that IVF treatments would be successful in the case of infertility. Nearly 9 in 10 participants want to have children in the future and viewed parenthood as a highly important aspect of their future lives. Delaying childbearing based on incorrect perceptions of female fertility could lead to involuntary childlessness. Education regarding fertility issues is necessary to help men and women make informed reproductive decisions that are based on accurate information rather than incorrect perceptions.
Full Text Available Midlife cardiovascular risk factors, including diabetes, hypertension, dyslipemia, and an unhealthy lifestyle, have been linked to subsequent incidence, delay of onset, and progression rate of Alzheimer disease and vascular dementia. Conversely, optimal treatment of cardiovascular risk factors prevents and slows down age-related cognitive disorders. The impact of antihypertensive therapy on cognitive outcome in patients with hypertension was assessed in large trials which demonstrated a reduction in progression of MRI white matter hyperintensities, in cognitive decline and in incidence of dementia. Large-scale database correlated statin use and reduction in the incidence of dementia, mainly in patients with documented atherosclerosis, but clinical trials failed to reach similar conclusions. Whether a multitargeted intervention would substantially improve protection, quality of life, and reduce medical cost expenditures in patients with lower risk profile has not been ascertained. This would require appropriately designed trials targeting large populations and focusing on cognitive decline as a primary outcome endpoint.
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 ...
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
Owoo, Nkechi S; Agyei-Mensah, Samuel; Onuoha, Emily
According to the demographic transition theory, fertility rates fall in response to declines in child mortality rates. Although national statistics indicate that child mortality rates have been declining over time, Ghana's fertility rates appear to have stalled. This paper hypothesises that women's fertility behaviours may be more responsive to child mortality experiences at more localised levels. Using all rounds of the Ghana Demographic and Health Surveys (1988-2008) and employing a variety of spatial and empirical estimation techniques, results indicate that in addition to own-child mortality, neighbourhood child mortality shocks are also a determinant of women's fertility in Ghana. Women in neighbourhoods with large child mortality shocks may desire more children as an "insurance" against future losses, as a result of their increased perceptions of own-child mortality risks.
Sansone, Andrea; Di Dato, Carla; de Angelis, Cristina; Menafra, Davide; Pozza, Carlotta; Pivonello, Rosario; Isidori, Andrea; Gianfrilli, Daniele
In recent decades, the decline in human fertility has become increasingly more worrying: while therapeutic interventions might help, they are vexing for the couple and often burdened with high failure rates and costs. Prevention is the most successful approach to fertility disorders in males and females alike. We performed a literature review on three of the most common unhealthy habits - tobacco, alcohol and drug addiction - and their reported effects on male fertility. Tobacco smoking is remarkably common in most first-world countries; despite a progressive decline in the US, recent reports suggest a prevalence of more than 30% in subjects of reproductive age - a disturbing perspective, given the well-known ill-effects on reproductive and sexual function as well as general health. Alcohol consumption is often considered socially acceptable, but its negative effects on gonadal function have been consistently reported in the last 30 years. Several studies have reported a variety of negative effects on male fertility following drug abuse - a worrying phenomenon, as illicit drug consumption is on the rise, most notably in younger subjects. While evidence in these regards is still far from solid, mostly as a result of several confounding factors, it is safe to assume that cessation of tobacco smoking, alcohol consumption and recreational drug addiction might represent the best course of action for any couple trying to achieve pregnancy.
Mackenbach, J. P.; Looman, C. W.; Kunst, A. E.; Habbema, J. D.; van der Maas, P. J.
In The Netherlands, as in many other industrialized countries, recent mortality developments have been characterized by rapid declines for a number of important causes of death. The results of an analysis of regional variation in mortality decline within The Netherlands are reported, covering the
Coblentz, W K; Akins, M S; Cavadini, J S; Jokela, W E
Applications of soil amendments containing N are part of routine forage-management strategies for grasses, with a primary goal of increasing forage yield. However, the effects of N fertilization on forage nutritive value, estimates of energy density, and in vitro dry matter or neutral detergent fiber disappearance sometimes have been erratic or inconsistent. Our objectives were to evaluate the effects of N fertilization on the nutritive value of a single cultivar (ForagePlus, Kratz Farms, Slinger, WI) of fall-grown oat fertilized at planting with 20, 40, 60, 80, or 100 kg of N/ha of urea or 2 rates of dairy slurry (42,300 or 84,600 L/ha). Nitrogen fertilization exhibited consistent effects on fiber components; forages fertilized with urea or dairy slurry had greater concentrations of fiber components compared with those harvested from unfertilized check plots (0 kg of N/ha), and fiber concentrations increased linearly with urea fertilization rate. In contrast, concentrations of water-soluble carbohydrates were greatest for unfertilized forages (21.2%), but declined linearly with urea fertilization, exhibiting a minimum of 13.5% at the 80 kg of N/ha urea application rate. Similarly, nonfiber carbohydrates also declined linearly, from 34.8% for unfertilized check plots to a minimum of 24.6% at the 80 kg of N/ha urea application rate. Fertilization with urea resulted in consistent linear increases in crude protein (CP), neutral detergent soluble CP, neutral detergent insoluble CP, and acid detergent insoluble CP; however, the partitioning of CP on the basis of association with specific fiber fractions could not be related to N fertilization when concentrations were expressed on a percentage of CP basis. The summative calculation of energy, expressed as total digestible nutrients was closely related to N fertilization rate during both the 2013 (y = -0.038x + 72.2; R2 = 0.961) and 2014 (y = -0.040x + 69.2; R2 = 0.771) production years. Following 30- or 48-h incubations
Mensah, George A; Wei, Gina S; Sorlie, Paul D; Fine, Lawrence J; Rosenberg, Yves; Kaufmann, Peter G; Mussolino, Michael E; Hsu, Lucy L; Addou, Ebyan; Engelgau, Michael M; Gordon, David
If the control of infectious diseases was the public health success story of the first half of the 20th century, then the decline in mortality from coronary heart disease and stroke has been the success story of the century's past 4 decades. The early phase of this decline in coronary heart disease and stroke was unexpected and controversial when first reported in the mid-1970s, having followed 60 years of gradual increase as the US population aged. However, in 1978, the participants in a conference convened by the National Heart, Lung, and Blood Institute concluded that a significant recent downtick in coronary heart disease and stroke mortality rates had definitely occurred, at least in the US Since 1978, a sharp decline in mortality rates from coronary heart disease and stroke has become unmistakable throughout the industrialized world, with age-adjusted mortality rates having declined to about one third of their 1960s baseline by 2000. Models have shown that this remarkable decline has been fueled by rapid progress in both prevention and treatment, including precipitous declines in cigarette smoking, improvements in hypertension treatment and control, widespread use of statins to lower circulating cholesterol levels, and the development and timely use of thrombolysis and stents in acute coronary syndrome to limit or prevent infarction. However, despite the huge growth in knowledge and advances in prevention and treatment, there remain many questions about this decline. In fact, there is evidence that the rate of decline may have abated and may even be showing early signs of reversal in some population groups. The National Heart, Lung, and Blood Institute, through a request for information, is soliciting input that could inform a follow-up conference on or near the 40th anniversary of the original landmark conference to further explore these trends in cardiovascular mortality in the context of what has come before and what may lie ahead. © 2017 American Heart
Kagabo, M.D.; Stroosnijder, L.; Visser, S.M.; Moore, D.
Crop productivity in Rwanda is declining as a result of intensive farming on steep slopes, which leads to soil loss and declining soil fertility particularly in the northern highlands. Slow-forming terraces have been widely adopted in the northern highlands of Rwanda to control soil erosion however
Xu, Z.; Guan, Z; Jayne, T.S.; Black, R
Major Findings: The additional maize produced from a given amount of fertilizer applied varied widely across households even after largely controlling for soil and rainfall conditions. The median estimated response rate was 15.9kgs of maize per kg nitrogen applied; Under the range of conditions and smallholder management practices, average maize fertilizer response rates declined as the application rate increased beyond 2 bags of urea and 2 bags of D compound; Factors raising the response rat...
Hussein, Julia; Bell, Jacqueline; Dar Iang, Maureen; Mesko, Natasha; Amery, Jenny; Graham, Wendy
A decline in the national maternal mortality ratio in Nepal has been observed from surveys conducted between 1996 and 2008. This paper aims to assess the plausibility of the decline and to identify drivers of change. National and sub-national trends in mortality data were investigated using existing demographic and health surveys and maternal mortality and morbidity surveys. Potential drivers of the variation in maternal mortality between districts were identified by regressing district-level indicators from the Nepal demographic health surveys against maternal mortality estimates. A statistically significant decline of the maternal mortality ratio from 539 maternal deaths to 281 per 100,000 (95% CI 91,507) live births between 1993 and 2003 was demonstrated. The sub-national changes are of similar magnitude and direction to those observed nationally, and in the terai region (plains) the differences are statistically significant with a reduction of 361 per 100,000 live births (95% CI 36,686) during the same time period. The reduction in fertility, changes in education and wealth, improvements in components of the human development index, gender empowerment and anaemia each explained more than 10% of the district variation in maternal mortality. A number of limitations in each of the data sources used were identified. Of these, the most important relate to the underestimation of numbers of deaths. It is likely that there has been a decline in Nepal's maternal mortality since 1993. This is good news for the country's sustained commitments in this area. Conclusions on the magnitude, pattern of the change and drivers of the decline are constrained by lack of data. We recommend close tracking of maternal mortality and its determinants in Nepal, attention to the communication of future estimates, and various options for bridging data gaps.
Full Text Available BACKGROUND: A decline in the national maternal mortality ratio in Nepal has been observed from surveys conducted between 1996 and 2008. This paper aims to assess the plausibility of the decline and to identify drivers of change. METHODS: National and sub-national trends in mortality data were investigated using existing demographic and health surveys and maternal mortality and morbidity surveys. Potential drivers of the variation in maternal mortality between districts were identified by regressing district-level indicators from the Nepal demographic health surveys against maternal mortality estimates. RESULTS: A statistically significant decline of the maternal mortality ratio from 539 maternal deaths to 281 per 100,000 (95% CI 91,507 live births between 1993 and 2003 was demonstrated. The sub-national changes are of similar magnitude and direction to those observed nationally, and in the terai region (plains the differences are statistically significant with a reduction of 361 per 100,000 live births (95% CI 36,686 during the same time period. The reduction in fertility, changes in education and wealth, improvements in components of the human development index, gender empowerment and anaemia each explained more than 10% of the district variation in maternal mortality. A number of limitations in each of the data sources used were identified. Of these, the most important relate to the underestimation of numbers of deaths. CONCLUSION: It is likely that there has been a decline in Nepal's maternal mortality since 1993. This is good news for the country's sustained commitments in this area. Conclusions on the magnitude, pattern of the change and drivers of the decline are constrained by lack of data. We recommend close tracking of maternal mortality and its determinants in Nepal, attention to the communication of future estimates, and various options for bridging data gaps.
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.
Jensen, Martin Blomberg; Priskorn, Lærke; Jensen, Tina Kold
OBJECTIVE: Increasing age at first childbirth has been suggested to increase the risk for infertility. Our objective is to determine whether women above thirty years of age historically have been able to sustain fertility rates above replacement level. DESIGN: A descriptive nationwide Danish study...... to determine total and age specific fertility rates. RESULTS: Total fertility rate (TFR) decreased from 4.1 to 1.8 children per woman and age specific fertility also decreased from 1901 to 2014. Women aged 30-34, 35-39 or 40-44 years in the first decade of the 20th century had higher fertility rates than...... for 10% of TFR in 1901 compared with 4% in 2014 despite usage of assisted reproduction. CONCLUSION: This nationwide study shows that women above 30 years of age historically have been able to sustain fertility rates above replacement level. This implies that other factors besides age are strong...
Sevel, L.; Ingerslev, Morten; Nord-Larsen, Thomas
Short rotation coppice (SRC) willow is an emerging cropping system in focus for production of biomass for energy. To increase production, the willow is commonly fertilized, but studies have shown differing effects of fertilization on biomass production, ranging from almost no response to consider......Short rotation coppice (SRC) willow is an emerging cropping system in focus for production of biomass for energy. To increase production, the willow is commonly fertilized, but studies have shown differing effects of fertilization on biomass production, ranging from almost no response...... to considerable positive effects. Focus has also been on replacing mineral fertilizer with organic waste products, such as manure and sludge. However, the effect on biomass production and environmental impact of various dosage and types of fertilizer is not well described. Therefore we studied the environmental...
Trees with obligate ectomycorrhiza are more sensitive to environmental stress than those without ectomycorrhiza or with facultative ectomycorrhiza. With spruce seedlings growing in humus material from a declining spruce forest an experimental proof was given, that reduction of the mineral nitrogen content by adding sawdust to the rooting substrate increases the share of root tips converted to ectomycorrhizas. A close correlation has been found between the mycorrhiza frequency and the number of root tips. This means, that the ramification of a root system is the more intense the better the conditions for mycorrhizal development are.
Billari, Francesco C.; Giuntella, Osea; Stella, Luca
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...
Markow, Therese Ann
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 asso...
National Oceanic and Atmospheric Administration, Department of Commerce — This data set includes experimental results of fertilization assays to characterize genetic compatibility between individual parental genotypes. Targeted species...
Bishop, D. A.; Beier, C. M.; Pederson, N.; Lawrence, G. B.; Stella, J. C.; Sullivan, T. J.
Sugar maple (Acer saccharum Marsh) is among the most ecologically, economically and culturally important trees in North America, but has experienced a decline disease across much of its range. We investigated the climatic and edaphic factors associated with A. saccharum growth in the Adirondack Mountains (USA) using a well-replicated tree-ring network incorporating a range of soil fertility (base cation availability). We found that nearly 3 in 4 A. saccharum trees exhibited declining growth rates during the last several decades, regardless of tree age or size. Although diameter growth was consistently higher on base-rich soils, the negative trends in growth were largely consistent across the soil chemistry gradient. Sensitivity of sugar maple growth to climatic variability was overall weaker than expected, but were also non-stationary during the 20th century. We observed increasingly positive responses to late-winter precipitation, increasingly negative responses to growing season temperatures, and strong positive responses to moisture availability during the 1960s drought that became much weaker during the recent pluvial. Further study is needed of these factors and their interactions as potential mechanisms for sugar maple growth decline.
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.
Ober, C. [Univ. of Chicago, IL (United States)
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.
consumed and 120 ml/h carbon dioxide (CO2) was excreted. This stage was followed by a decline in metabolic rate to approximately 75 % of the peak value. The gas exchange of ostrich eggs incubated in this study at 36 °C was compared with studies where incubation temperatures of 35, 35.5 and 36.3 °C were used.
Rindfuss, R R; Reed, J S; John, C
On 17 May 1954 the Supreme Court, in its decision in Brown v. Board of Education, declared de jure segregation of the public schools to be unconstitutional. It is argued here that a consequence of that decision was a decline in childbearing among white Southerners. In the nation as a whole, period fertility rates increased between 1954 and 1955, but in 9 of the 11 former Confederate states they decreased. Further analysis shows that these Southern fertility decreases began about 12 months after the Supreme Court decision. This variation in behavior in reaction to a historical event has important implications for the explanation and prediction of fertility.
Zhang, Shujuan; Wang, Li; Ma, Fang; Zhang, Xue; Li, Zhe; Li, Shiyang; Jiang, Xiaofeng
Our study sought to assess how much phosphorus (P) runoff from paddy fields could be cut down by fertilizer management and inoculation with arbuscular mycorrhizal fungi. A field experiment was conducted in Lalin River basin, in the northeast China: six nitrogen-phosphorus-potassium fertilizer levels were provided (0, 20%, 40%, 60%, 80%, and 100% of the recommended fertilizer supply), with or without inoculation with Glomus mosseae. The volume and concentrations of particle P (PP) and dissolved P (DP) were measured for each runoff during the rice growing season. It was found that the seasonal P runoff, including DP and PP, under the local fertilization was 3.7 kg/ha, with PP, rather than DP, being the main form of P in runoff water. Additionally, the seasonal P runoff dropped only by 8.9% when fertilization decreased by 20%; rice yields decreased with declining fertilization. We also found that inoculation increased rice yields and decreased P runoff at each fertilizer level and these effects were lower under higher fertilization. Conclusively, while rice yields were guaranteed arbuscular mycorrhizal inoculation and fertilizer management would play a key role in reducing P runoff from paddy fields. Copyright © 2015. Published by Elsevier B.V.
Keywords: smallholder farmers, soil fertility, experimentation, "inconvenience", realist.The focus in this thesis is to form a view of how well soil fertility research performs within the ever shifting smallholder contexts. This study examined application of agro-ecological
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 ...
DeWeaver, Eric T.; Bitz, Cecilia M.; Tremblay, L.-Bruno
This volume addresses the rapid decline of Arctic sea ice, placing recent sea ice decline in the context of past observations, climate model simulations and projections, and simple models of the climate sensitivity of sea ice. Highlights of the work presented here include • An appraisal of the role played by wind forcing in driving the decline; • A reconstruction of Arctic sea ice conditions prior to human observations, based on proxy data from sediments; • A modeling approach for assessing the impact of sea ice decline on polar bears, used as input to the U.S. Fish and Wildlife Service's decision to list the polar bear as a threatened species under the Endangered Species Act; • Contrasting studies on the existence of a "tipping point," beyond which Arctic sea ice decline will become (or has already become) irreversible, including an examination of the role of the small ice cap instability in global warming simulations; • A significant summertime atmospheric response to sea ice reduction in an atmospheric general circulation model, suggesting a positive feedback and the potential for short-term climate prediction. The book will be of interest to researchers attempting to understand the recent behavior of Arctic sea ice, model projections of future sea ice loss, and the consequences of sea ice loss for the natural and human systems of the Arctic.
Holl, K D; Daily, G C; Ehrlich, P R
Costa Rica achieved a substantial reduction in its overall fertility rate in a very short period of time. The halving of the fertility rate which occurred in less than ten years in Costa Rica transpired over the course of 100 years in France and 170 in Sweden. The level of contraceptive use in Costa Rica is twice that in other Central American nations. The authors summarize the recent demographic history of Costa Rica and review factors influencing its remarkable fertility decline. They then discuss possible explanations for the ensuing fertility plateau and conclude by suggesting strategies for affecting a further decrease in fertility rates. With regard to the reasons for the fertility plateau, cultural factors, socioeconomic factors, declining government commitment and family planning services, education, and the Church are considered. To reduce the level of fertility even further, the authors recommend that the government adopt a clear population policy which could serve as a basis for other changes such as increased support of family planning programs, improvements in the educational system, increased women's status and employment opportunities, and extensive education in schools and through the mass media on the socioeconomic and environmental effects of overpopulation. It is important to increase Costa Ricans' understanding of the negative impacts of continued population growth and the role of individual family planning decisions in that growth.
Mohanty, Sanjay K; Rajbhar, Mamta
Demographic research in India over the last two decades has focused extensively on fertility change and gender bias at the micro-level, and less has been done at the district level. Using data from the Census of India 1991-2011 and other sources, this paper shows the broad pattern of fertility transition and trends in the child sex ratio in India, and examines the determinants of the child sex ratio at the district level. During 1991-2011, while the Total Fertility Rate (TFR) declined by 1.2 children per woman, the child sex ratio fell by 30 points in the districts of India. However, the reduction in fertility was slower in the high-fertility compared with the low-fertility districts. The gender differential in under-five mortality increased in many districts of India over the study period. The decline in the child sex ratio was higher in the transitional compared with the low-fertility districts. The transitional districts are at higher risk of a low child sex ratio due to an increased gender differential in mortality and increase in the practice of sex-selective abortions. The sex ratio at birth and gender differential in mortality explains one-third of the variation, while region alone explains a quarter of the variation in the child sex ratio in the districts of India.
Buckley, Rachel F; Schultz, Aaron P; Hedden, Trey; Papp, Kathryn V; Hanseeuw, Bernard J; Marshall, Gad; Sepulcre, Jorge; Smith, Emily E; Rentz, Dorene M; Johnson, Keith A; Sperling, Reisa A; Chhatwal, Jasmeer P
To examine the utility of resting-state functional connectivity MRI (rs-fcMRI) measurements of network integrity as a predictor of future cognitive decline in preclinical Alzheimer disease (AD). A total of 237 clinically normal older adults (aged 63-90 years, Clinical Dementia Rating 0) underwent baseline β-amyloid (Aβ) imaging with Pittsburgh compound B PET and structural and rs-fcMRI. We identified 7 networks for analysis, including 4 cognitive networks (default, salience, dorsal attention, and frontoparietal control) and 3 noncognitive networks (primary visual, extrastriate visual, motor). Using linear and curvilinear mixed models, we used baseline connectivity in these networks to predict longitudinal changes in preclinical Alzheimer cognitive composite (PACC) performance, both alone and interacting with Aβ burden. Median neuropsychological follow-up was 3 years. Baseline connectivity in the default, salience, and control networks predicted longitudinal PACC decline, unlike connectivity in the dorsal attention and all noncognitive networks. Default, salience, and control network connectivity was also synergistic with Aβ burden in predicting decline, with combined higher Aβ and lower connectivity predicting the steepest curvilinear decline in PACC performance. In clinically normal older adults, lower functional connectivity predicted more rapid decline in PACC scores over time, particularly when coupled with increased Aβ burden. Among examined networks, default, salience, and control networks were the strongest predictors of rate of change in PACC scores, with the inflection point of greatest decline beyond the fourth year of follow-up. These results suggest that rs-fcMRI may be a useful predictor of early, AD-related cognitive decline in clinical research settings. © 2017 American Academy of Neurology.
Gomez, Scarlett Lin; Canchola, Alison J; Nelson, David O; Keegan, Theresa H M; Clarke, Christina A; Cheng, Iona; Shariff-Marco, Salma; DeRouen, Mindy; Catalano, Ralph; Satariano, William A; Davidson-Allen, Kathleen; Glaser, Sally L
In recent years, cancer case counts in the U.S. underwent a large, rapid decline-an unexpected change given population growth for older persons at highest cancer risk. As these declines coincided with the Great Recession, we examined whether they were related to economic conditions. Using California Cancer Registry data from California's 30 most populous counties, we analyzed trends in cancer incidence during pre-recession (1996-2007) and recession/recovery (2008-2012) periods for all cancers combined and the ten most common sites. We evaluated the recession's association with rates using a multifactorial index that measured recession impact, and modeled associations between case counts and county-level unemployment rates using Poisson regression. Yearly cancer incidence rate declines were greater during the recession/recovery (3.3% among males, 1.4% among females) than before (0.7 and 0.5%, respectively), particularly for prostate, lung, and colorectal cancers. Lower case counts, especially for prostate and liver cancer among males and breast cancer, melanoma, and ovarian cancer among females, were associated with higher unemployment rates, irrespective of time period, but independent of secular effects. The associations for melanoma translated up to a 3.6% decrease in cases with each 1% increase in unemployment. Incidence declines were not greater in counties with higher recession impact index. Although recent declines in incidence of certain cancers are not differentially impacted by economic conditions related to the Great Recession relative to pre-recession conditions, the large recent absolute declines in the case counts of some cancer may be attributable to the large declines in unemployment in the recessionary period. This may occur through decreased engagement in preventive health behaviors, particularly for clinically less urgent cancers. Continued monitoring of trends is important to detect any rises in incidence rates as deferred diagnoses come to
Triebner, Kai; Matulonga, Bobette; Johannessen, Ane; Suske, Sandra; Benediktsdóttir, Bryndís; Demoly, Pascal; Dharmage, Shyamali C; Franklin, Karl A; Garcia-Aymerich, Judith; Gullón Blanco, José Antonio; Heinrich, Joachim; Holm, Mathias; Jarvis, Debbie; Jõgi, Rain; Lindberg, Eva; Moratalla Rovira, Jesús Martínez; Muniozguren Agirre, Nerea; Pin, Isabelle; Probst-Hensch, Nicole; Puggini, Luca; Raherison, Chantal; Sánchez-Ramos, José Luis; Schlünssen, Vivi; Sunyer, Jordi; Svanes, Cecilie; Hustad, Steinar; Leynaert, Bénédicte; Gómez Real, Francisco
Menopause is associated with changes in sex hormones, which affect immunity, inflammation, and osteoporosis and may impair lung function. Lung function decline has not previously been investigated in relation to menopause. To study whether lung function decline, assessed by FVC and FEV1, is accelerated in women who undergo menopause. The population-based longitudinal European Community Respiratory Health Survey provided serum samples, spirometry, and questionnaire data about respiratory and reproductive health from three study waves (n = 1,438). We measured follicle-stimulating hormone and luteinizing hormone and added information on menstrual patterns to determine menopausal status using latent class analysis. Associations with lung function decline were investigated using linear mixed effects models, adjusting for age, height, weight, pack-years, current smoking, age at completed full-time education, spirometer, and including study center as random effect. Menopausal status was associated with accelerated lung function decline. The adjusted mean FVC decline was increased by -10.2 ml/yr (95% confidence interval [CI], -13.1 to -7.2) in transitional women and -12.5 ml/yr (95% CI, -16.2 to -8.9) in post-menopausal women, compared with women menstruating regularly. The adjusted mean FEV1 decline increased by -3.8 ml/yr (95% CI, -6.3 to -2.9) in transitional women and -5.2 ml/yr (95% CI, -8.3 to -2.0) in post-menopausal women. Lung function declined more rapidly among transitional and post-menopausal women, in particular for FVC, beyond the expected age change. Clinicians should be aware that respiratory health often deteriorates during reproductive aging.
Gill, Dawn P; Hubbard, Rebecca A; Koepsell, Thomas D; Borrie, Michael J; Petrella, Robert J; Knopman, David S; Kukull, Walter A
The purpose of this study was to estimate differences in rates of functional decline in Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and vascular dementia (VaD) and whether differences vary by age or sex. Data came from 32 U.S. Alzheimer's Disease Centers. The cohort of participants (n = 5848) were ≥60 years of age and had clinical dementia with a primary etiologic diagnosis of probable AD, DLB, or probable VaD; a Clinical Dementia Rating-Sum of Boxes score Dementia diagnoses were assigned using standard criteria. Annual mean rate of change of the Functional Activities Questionnaire (FAQ) score was modeled using multiple linear regression with generalized estimating equations adjusted for demographics, comorbidities, years since onset, and cognitive status (mean follow-up = 2.0 years). FAQ declined more slowly over time in those with VaD compared with AD (difference in mean annual rate of change: -0.91; 95% confidence interval [CI]: -1.68, -0.14). VaD participants also declined at a slower rate than DLB participants, but this difference was not statistically significant (-0.61; 95% CI: -1.45, 0.24). There was no significant difference between DLB and AD. Within each group, rate of decline was more rapid for the youngest participants. In this sample, findings suggested that VaD patients declined in their functional abilities at a slower rate compared with AD patients and that there were no significant differences in rate of functional decline between patients with DLB compared with those with either AD or VaD. These results may provide guidance to clinicians about average expected rates of functional decline in three common dementia types. Copyright © 2013 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
Radiotherapy - fertility; Radiation - fertility; Chemotherapy - fertility; Sexual dysfunction - cancer treatment ... Numbness or pain in the genitals Problems with fertility Many people also have emotional side effects after ...
De Oliveira, O; Garcia, B
Among the major transformations affecting Mexican women in recent decades were their growing participation in the labor market and the fertility decline that began in the 1970s with widespread access to contraception. Data from 3 major Mexican fertility surveys, employment surveys, and censuses are used to analyze changes in female employment and their determinants during the years of economic recession in the 1980s. The main characteristics of the Mexican fertility decline are described, and the relationship between fertility and female employment before and during the economic recession is scrutinized for different social sectors. Suggestions for research on the affects of these changes on the social condition of Mexican women are then presented. The proportions of Mexican women over 12 years old who declared themselves economically active increased from 16% in 1970 to 21% in 1979 and 32% in 1987. Until the 1970s the majority of employed women were young and single or childless. But a clear increase occurred between 1976-87 in the economic participation of older women in union. Economic participation of low income and less educated women increased as they sought work or created their own in response to deteriorating living conditions during the recession. Young women with intermediate or higher educational levels did not increase their relative presence in the labor market in the same period. The marked increase in economic participation of less educated women in union with small children was accompanied by a significant increase in manual occupations. Between 1982-87, the proportion of women aged 20-49 in nonsalaried manual occupations rose from 7.6% to 18.5%. Mexico's fertility decline has been well documented. The total fertility rate declined from 6.3 in 1973 to 3.8 in 1986, while the percentage of women in union using a contraceptive method increased from 30.2 in 1976 to 52.7 in 1987. Fertility differentials have been declining but are still considerable
Thomas N. Maloney
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.
Njor, Sisse Helle; Schwartz, Walter; Blichert-Toft, Mogens
OBJECTIVES: When estimating the decline in breast cancer mortality attributable to screening, the challenge is to provide valid comparison groups and to distinguish the screening effect from other effects. In Funen, Denmark, multidisciplinary breast cancer management teams started before screening...... was introduced; both activities came later in the rest of Denmark. Because Denmark had national protocols for breast cancer treatment, but hardly any opportunistic screening, Funen formed a "natural experiment", providing valid comparison groups and enabling the separation of the effect of screening from other...... factors. METHODS: Using Poisson regression we compared the observed breast cancer mortality rate in Funen after implementation of screening with the expected rate without screening. The latter was estimated from breast cancer mortality in the rest of Denmark controlled for historical differences between...
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
Overweight and obesity are increasing worldwide. This has major adverse consequences for health in general and fertility in women in particular. With the increasing number of women in reproductive age being obese, there is also an increasing need for fertility treatment. And with more pregnant women
Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik
To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....
Cortes, D; Thorup, J M; Lindenberg, S
. CONCLUSIONS: The age matched number of spermatogonia per tubular cross section is significant in regard to fertility potential, and a value of 1% or less (approximately Sertoli cells only) may predict low fertility potential. To our knowledge Sertoli cells only have not been observed before 15 months of life...
Nahata, Leena; Sivaraman, Vidya; Quinn, Gwendolyn P
To assess fertility counseling and preservation practices among children, adolescents, and young adults with rheumatic diseases undergoing cyclophosphamide (CTX) treatment. Retrospective chart review (2006-2016). Academic pediatric center. Male and female patients with systemic lupus erythematosus, Wegener's granulomatosis/granulomatosis with polyangiitis, or other vaculitides, receiving CTX treatment. None. Documentation of fertility counseling and fertility preservation. A total of 58 subjects met the inclusion criteria; 5 were excluded due to incomplete records, thus N = 53. Of these 75% were female (N = 40). Median age was 14 years at diagnosis and 15 years at first CTX treatment. A total of 51% of subjects (69% of males and 45% of females) had no documentation about potential fertility loss before CTX treatment. Among females where fertility counseling was documented, the only fertility preservation option discussed was leuprolide acetate (LA), which was pursued in all of these cases. Of 13 males (77% postpubertal), 3 were offered sperm banking, of whom 2 declined and the other attempted after treatment began and was azoospermic. Of 53 patients, 1 was referred to a fertility specialist. Mean cumulative CTX dose was 9.2 g in males and 8 g in females. Based on these findings, increasing awareness about infertility risk, fertility preservation options, and referral to fertility specialists is needed among pediatric rheumatologists. Prospective studies are needed to assess fertility outcomes in this patient population (including effectiveness of LA with regard to pregnancy rates [PRs]), as well as barriers/facilitators to fertility counseling and fertility preservation. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Chan, C H Y; Chan, T H Y; Peterson, B D; Lampic, C; Tam, M Y J
What are the levels of awareness regarding female fertility and the intentions and attitudes towards parenthood among Chinese university students in Hong Kong compared with their counterparts in the West? Chinese university students in Hong Kong were similarly over-optimistic about the age-related fertility decline, although they were less inclined to have children and undergo fertility treatment compared with their Western counterparts. Past studies of highly educated young adults in Europe and the USA have found that they are not sufficiently aware of the age-related decline in female fertility, and falsely believe that advanced reproductive treatments such as IVF will overcome fertility problems associated with age. Little is known about the perceptions of Chinese students in Hong Kong, a modernized Chinese city where the fertility rate is among the lowest in the world. An online cross-sectional survey of Chinese university students in Hong Kong was conducted in 2013. Results were compared with two similar studies in Sweden and the USA. A total of 367 university students in Hong Kong (275 female, 92 male; mean age 23) responded to an e-mail invitation to participate in an online survey. Intentions and attitudes towards parenthood and awareness regarding female fertility were assessed using the Swedish Fertility Awareness Questionnaire. Like their Western counterparts, a large proportion of Chinese university students underestimated the age-related fertility decline (92%) and overestimated the fertility treatment success rate (66%). However, they were less inclined to have children, were more aware of and less concerned with infertility and were less motivated to seek solutions in the event of a fertility problem. These comparisons were significant at P University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: email@example.com.
Roy, Amit H.
Fertilizers provide plants with the nutrients they need for their growth and development. Plants live, grow, and reproduce by taking up water and nutrients, carbon dioxide from the air, and energy from the sun. Apart from carbon, hydrogen, and oxygen, which collectively make up 90-95 percent of the dry matter of all plants, other nutrients needed by plants come essentially from the media in which they grow—essentially in the soil. The other nutrients are subdivided into primary nutrients (nitrogen, phosphorus, and potassium) and secondary nutrients (calcium, magnesium, and sulfur). In addition, plants also need other nutrients in much smaller amounts, and they are referred to as micro-nutrients (boron, chlorine, copper, iron, manganese, molybdenum, and zinc).
Xie, Shan; Lan, Yifei; He, Lei; Jiao, Yang; Wu, Yong
ARPS decline curves is the most commonly used in oil and gas field due to its minimal data requirements and ease application. And prediction of production decline which is based on ARPS analysis rely on known decline type. However, when coefficient index are very approximate under different decline type, it is difficult to directly recognize decline trend of matched curves. Due to difficulties above, based on simulation results of multi-factor response experiments, a new dynamic decline prediction model is introduced with using multiple linear regression of influence factors. First of all, according to study of effect factors of production decline, interaction experimental schemes are designed. Based on simulated results, annual decline rate is predicted by decline model. Moreover, the new method is applied in A gas filed of Ordos Basin as example to illustrate reliability. The result commit that the new model can directly predict decline tendency without needing recognize decline style. From arithmetic aspect, it also take advantage of high veracity. Finally, the new method improves the evaluation method of gas well production decline in low permeability gas reservoir, which also provides technical support for further understanding of tight gas field development laws.
Full Text Available ... for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Patient Pocket Guides Patient Pocket ... for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Welcome to SaveMyFertility.org Preserving ...
Full Text Available ... approach the subject of fertility preservation with their cancer-stricken child? How is the Oncofertility Consortium addressing the fertility preservation needs of children? How do cancer and cancer treatment affect a child's fertility? Why ...
Full Text Available ... to SaveMyFertility.org Preserving Fertility Before and After Cancer Treatment SaveMyFertility.org is an authoritative resource for adult cancer patients and the parents of children with cancer ...
into account. Most African countries with data available from more than one survey appear to have experienced a trend toward decline in the number of very early marriages and pregnancies. Such declines as have occurred are probably the result of urbanization and school attendance rather than any specific policy measure. Programs targeted to adolescents should distinguish between the risks of early pregnancy and of premarital fertility. Increased attention should be directed to rural women who marry and have children at very young ages.
Full Text Available There is growing concern that current pollinator decline will affect the reproduction of plant species, potentially driving a decline in plant population densities. We experimentally tested whether a reduction in flower visitation caused a reduction in fertilization rate in several species, and whether any reduction in fecundity of species depends on their degree of reproductive dependence on pollinators and their attractiveness for pollinators. We recorded visitation rate, fertilization rate, seed weight, flower size and density of nineteen insect-pollinated perennial herbs inside thirty 2 x 2 m dome-shaped cages covered with fishnet (experimental plots and in thirty control plots in a Norwegian hay meadow. We used a bagging experiment to estimate the ability of the study species to produce seeds in the absence of pollinators. The visitation rate for fifteen of nineteen study species was lower inside cages than outside and only three of the fifteen species showed significantly reduced fertilization rates in the experimental plots. The magnitude of reduction in fertilization rate was positively related to the degree of pollinator dependence, but not to their attractiveness for pollinators or to the reduction in visitation rate. Seed weight was not affected by the experiment. The lack of an overall effect of reduced pollinator visitation on fertilization rate suggests that some species may be robust to a pollinator decline that could increase pollen limitation on plant reproduction. Our results suggest that species with greater pollinator dependence are more vulnerable to pollinator loss. NOTE: Supporting information to this article may be found in the left menu.
Full Text Available ... Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult ...
Ayele, Dawit Getnet
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.
Krolewski, Andrzej S; Skupien, Jan; Rossing, Peter; Warram, James H
A new model of diabetic nephropathy in type 1 diabetes emerged from our studies of Joslin Clinic patients. The dominant feature is progressive renal decline, not albuminuria. This decline is a unidirectional process commencing while patients have normal renal function and, in the majority, progressing steadily (linearly) to end-stage renal disease (ESRD). While an individual's rate of renal decline is constant, the estimated glomerular filtration rate (eGFR) slope varies widely among individuals from -72 to -3.0 ml/min/year. Kidney Disease: Improving Global Outcomes guidelines define rapid progression as rate of eGFR declines > 5 ml/min/year, a value exceeded by 80% of patients in Joslin's type 1 diabetes ESRD cohort. The extraordinary range of slopes within the rapid progression category prompted us to partition it into "very fast," "fast" and "moderate" decline. We showed, for the first time, that very fast and fast decline from normal eGFR to ESRD within 2 to 10 years constitutes 50% of the Joslin cohort. In this review we present data about frequency of fast decliners in both diabetes types, survey some mechanisms underlying fast renal decline, discuss methods of identifying patients at risk and comment on the need for effective therapeutic interventions. Whether the initiating mechanism of fast renal decline affects glomerulus, tubule, interstitium or vasculature is unknown. Since no animal model mimics progressive renal decline, studies in humans are needed. Prospective studies searching for markers predictive of the rate of renal decline yield findings that may make detection of fast decliners feasible. Identifying such patients will be the foundation for developing effective individualized methods to prevent or delay onset of ESRD in diabetes. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.
Dalsgård, Anne Line
Since the 1970s Brazil has experienced a remarkable decline in fertility. This decline has come about mainly due to illegal abortion and female sterilisation. The present study was conducted in a low-income neighbourhood in Recife, Northeast Brazil, where 37 percent of all women of reproductive...... age had been sterilised. For these women fertility control was not a question of constructing a prosperous future. Having few children might improve a family’s chances in relation to economy and upward mobility, but for most women the need to stop childbearing was related...... of irresponsibility and violence, their worth as citizens of the modern Brazilian society. Making ends meet economically was only the immediate concern – what was at stake was something more fundamental: Being fertile was an Achilles’ heel, a weakness that under certain conditions was directly associated with death...
Jenkins, Kurt J.; Barten, Neil L.
We evaluated population trends in the Mentasta caribou (Rangifer tarandus (L., 1758)) herd in Wrangell a?? St. Elias National Park and Preserve, Alaska, from 1990 to 1997 and determined factors contributing to its decline. We postulated that predation-related mortality of adult females and juveniles was the proximate cause of the decline, and that survival of juvenile caribou reflected interactions with winter severity, calving distribution, timing of births, density of caribou, and physical condition of neonates at birth. The population declined at its greatest rate from 1990 to 1993 (r = a??0.32) and at a lower rate from 1994 to 1997 (r = a??0.09). Recruitment (number of calves/100 females during September) averaged 4/100 during the rapid population decline from 1990 to 1993 and 13/100 from 1994 to 1997. Parturition rate of adult females ranged from 65% to 97%. Survival of adult females and juveniles ranged from 0.77 to 0.86 and from 0.00 to 0.22, respectively. Approximately 43%, 59%, and 79% of all juvenile mortality occurred by 1, 2, and 4 weeks of age, respectively. We confirmed predation-related mortality as the primary proximate cause of population decline, with gray wolves (Canis lupus L., 1758), bears (species of the genus Ursus L., 1758), and other predators accounting for 57%, 38%, and 5%, respectively, of all juvenile mortality, and bears causing disproportionate mortality among 0- to 1-week-old neonates. We supported the hypotheses that timing of birth and habitat conditions at the birth site, particularly mottled snow patterns, affected vulnerability and survival of neonates, and birth mass affected survival of juveniles through summer. We speculate that the population will continue to decline before reaching a low-density equilibrium that is sustained by density-dependent changes in the functional responses of predators.
Butts, Ian; Sørensen, Sune Riis; Politis, Sebastian Nikitas
Standardization of artificial fertilization protocols for the European eel, Anguilla anguilla, is a prerequisite for optimizing the use of available gametes in hatchery facilities and for conserving sperm from high quality males, which is either cryopreserved or in living gene banks. The objectives...... of this research were to provide a rapid, accurate and precise method to quantify sperm density by examining the relationship between sperm density and absorbance by use of a spectrophotometer, determine the optimal number of sperm required to fertilize eggs in a controlled setting, and explore how long eggs...... are receptive to fertilization post-stripping. Mean sperm density and absorbance at 350nm were 1.54e+10±4.95e+9sperm/mL and 1.91±0.22nm, respectively. Regression analysis demonstrated a highly significant positive relationship between sperm density and absorbance using a spectrophotometer at 350nm (R2=0.94, p
Maeda, Eri; Nakamura, Fumiaki; Boivin, Jacky; Kobayashi, Yasuki; Sugimori, Hiroki; Saito, Hidekazu
Although fertility educational initiatives have increased in developed countries to prevent infertility and to broaden fertility choices, the relationship between knowledge and behaviour is still poorly understood. In order to investigate the association between fertility knowledge and timing of childbearing, we investigated male and female participants between 35 and 44 years of age who had children (n = 640) from an online survey conducted in Japan in 2013. The age at which participants actually gave birth to or fathered their first child was compared between those who were aware for at least a decade of age-related decline in female fertility (hereinafter, those with past fertility knowledge) and those without. Age at first birth was significantly younger and more narrowly distributed among women with past fertility knowledge than among those without: 28.2 ± 3.4 vs. 29.8 ± 4.6 (mean ± SD). A multivariate linear regression analysis showed that women with past fertility knowledge gave birth to their first child 2.34 [95% confidence interval (CI): 1.09-3.59] years earlier compared to those without such knowledge. No significant relation existed among men. Being informed in young adulthood about the facts of fertility might be related to starting a family at an earlier age, although further longitudinal evaluation will be necessary.
the principle of gender equality. This concern may also result in reduced focus on ‘the other side of the story’, namely that 225 million women who wish to avoid or delay pregnancy are not using modern contraception. Such restrictive approaches contravene people’s right to “reproduce and the freedom to decide......, on average, women in countries with low birth rates want more children, while women in countries with very high birth rates want fewer on average. Therefore, the ‘right’ thing to do is also the ‘smart’ thing to do....
Kurjanska, Malgorzata; Lyngsie, Jacob
In recent years, Europe has entered a crisis of fertility. One policy solution that countries can, and some have moved to adopt to deal with low fertility rates, is to increase labor benefits granted to new parents, with a particular focus on extending maternity, not paternity, leave. We explore...... supporting an increase in Europe’s fertility rate, increasing maternity leave may also exacerbate gender inequalities tied to childrearing. Relying on alternative measures of in-home gender inequalities (e.g. gender conservatism), initial results provide compelling evidence that maternity benefits do affect...
Onda, Yuichi; Taniguchi, Keisuke; Wakiyama, Yoshifumi; Yoshimura, Kazuya; Smith, Hugh; Brake, Will; Iwagami, Sho; Kato, Hiroaki
The Fukushima Daiichi Nuclear Power Plant accident has released massive amount of radiocesium into the terrestrial environment, and the radiocecium have been moved through rainfall and erosional processes. Especially, radiocesium (Cs-137) transfer and flux through river network is important to understand the redistribution of radiocesium in terrestrial environment. An intensive field monitoring campaign has been started including mapping project, immediately after the Fukushima NPP accident including detailed monitoring site in upstream (Yamakiya site), and 30 monitoring sites in downstream river sites. In this presentation, I will present the initial and secondary decline of summary of environmental transfer studies after the Fukushima NPP accident The processes includes forest canopy to ground soil and aquifers, transfer to river and marine. The activity concentration of radiocesium of suspended sediment declining rapidly in rivers until about 1 year after the fallout, then decline slowly, but the tendency of rate of decline differs between rivers. The rate of decline in paddy field and headwater stream is quicker in initial decline followed by slower decline. However, the slow decline of activity concentration of suspend sediment in cropland and decline steadily. We will analyse the difference in initial and secondary decline between rivers using upstream land use and runoff characteristics.
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.
Full Text Available Abstract The decline in dairy herd fertility internationally has highlighted the limited impact of traditional veterinary approaches to bovine fertility management. Three questionnaire surveys were conducted at buiatrics conferences attended by veterinary practitioners on veterinary dairy herd fertility services (HFS in countries with a seasonal (Ireland, 47 respondents and non-seasonal breeding model (The Netherlands, 44 respondents and Portugal, 31 respondents. Of the 122 respondents, 73 (60% provided a HFS and 49 (40% did not. The majority (76% of all practitioners who responded stated that bovine fertility had declined in their practice clients' herds with inadequate cow management, inadequate nutrition and increased milk yield as the most important putative causes. The type of clients who adopted a herd fertility service were deemed more educated than average (70% of respondents, and/or had fertility problems (58% and/or large herds (53%. The main components of this service were routine postpartum examinations (95% of respondents, fertility records analysis (75% and ultrasound pregnancy examinations (69%. The number of planned visits per annum varied between an average of four in Ireland, where breeding is seasonal, and 23 in Portugal, where breeding is year-round. The benefits to both the practitioner and their clients from running a HFS were cited as better fertility, financial rewards and job satisfaction. For practitioners who did not run a HFS the main reasons given were no client demand (55% and lack of fertility records (33%. Better economic evidence to convince clients of the cost-benefit of such a service was seen as a major constraint to adoption of this service by 67% of practitioners.
Full Text Available Background: Ever since the Princeton European Fertility Project, structural and diffusion effects on fertility behavior have been juxtaposed. However, we still hardly know what the relative effects were of shifting socio-economic conditions and shifts in sociability in explaining the historical fertility decline. Objective: To what extent and how did structural and diffusion effects play a role in the adoption of fertility control in the Dutch historical fertility transition? Methods: A national data set was used with more than 3,000 maternity histories of married Dutch women aged 15-50, whose reproductive careers took place between 1870 and 1940. Apart from husbands' occupations, characteristics of the set of couples' marriage witnesses were included to measure their social networks. Cox regression analyses of age at last birth and negative binomial regressions of net family size were conducted. Results: Results indicate that unskilled laborers and farm laborers were laggards in the practice of fertility control during the Dutch fertility transition. Besides SES differentials, differences in couples' social networks were important in explaining fertility behavior. Those who had networks consisting of lateral kin, age peers, and people of urban background stopped childbearing earlier and had smaller families than other couples did. Particularly the presence of lateral kin of the bride and of female witnesses was strongly associated with smaller family size. Conclusions: The evidence lends support for so-called "blended diffusion models" and suggests that the fertility transition must be understood as much from the viewpoint of changed cost-benefit calculations related to structural changes, as from shifting patterns of sociability associated with the decline of patriarchy and the increasing lateralization and age homophily of people's social networks.
Carignan, Courtney C; Mínguez-Alarcón, Lidia; Williams, Paige L; Meeker, John D; Stapleton, Heather M; Butt, Craig M; Toth, Thomas L; Ford, Jennifer B; Hauser, Russ
Use of organophosphate flame retardants (PFRs) has increased over the past decade following the phase out of some brominated flame retardants, leading to increased human exposure. We recently reported that increasing maternal PFR exposure is associated with poorer pregnancy outcomes among women from a fertility clinic. Because a small epidemiologic study previously reported an inverse association between male PFR exposures and sperm motility, we sought to examine associations of paternal urinary concentrations of PFR metabolites and their partner's pregnancy outcomes. This analysis included 201 couples enrolled in the Environment and Reproductive Health (EARTH) prospective cohort study (2005-2015) who provided one or two urine samples per IVF cycle. In both the male and female partner, we measured five urinary PFR metabolites [bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), diphenyl phosphate (DPHP), isopropylphenyl phenyl phosphate (ip-PPP), tert-butylphenyl phenyl phosphate (tb-PPP) and bis(1-chloro-2-propyl) phosphate (BCIPP)] using negative electrospray ionization liquid chromatography tandem mass spectrometry (LC-MS/MS). The sum of the molar concentrations of the urinary PFR metabolites was calculated. We used multivariable generalized linear mixed models to evaluate the association of urinary concentrations of paternal PFR metabolites with IVF outcomes, accounting for multiple in vitro fertilization (IVF) cycles per couple. Models were adjusted for year of IVF treatment cycle, primary infertility diagnosis, and maternal urinary PFR metabolites as well as paternal and maternal age, body mass index, and race/ethnicity. Detection rates were high for paternal urinary concentrations of BDCIPP (84%), DPHP (87%) and ip-PPP (76%) but low for tb-PPP (12%) and zero for BCIPP (0%). We observed a significant 12% decline in the proportion of fertilized oocytes from the first to second quartile of male urinary ΣPFR and a 47% decline in the number of best quality embryos
Cao, L.; Caldeira, K.
It has been suggested that ocean fertilization could help diminish ocean acidification. Here, we quantitatively evaluate this suggestion. Ocean fertilization is one of several ocean methods proposed to mitigate atmospheric CO2 concentrations. The basic idea of this method is to enhance the biological uptake of atmospheric CO2 by stimulating net phytoplankton growth through the addition of iron to the surface ocean. Concern has been expressed that ocean fertilization may not be very effective at reducing atmospheric CO2 concentrations and may produce unintended environmental consequences. The rationale for thinking that ocean fertilization might help diminish ocean acidification is that dissolved inorganic carbon concentrations in the near-surface equilibrate with the atmosphere in about a year. If ocean fertilization could reduce atmospheric CO2 concentrations, it would also reduce surface ocean dissolved inorganic carbon concentrations, and thus diminish the degree of ocean acidification. To evaluate this line of thinking, we use a global ocean carbon cycle model with a simple representation of marine biology and investigate the maximum potential effect of ocean fertilization on ocean carbonate chemistry. We find that the effect of ocean fertilization on ocean acidification depends, in part, on the context in which ocean fertilization is performed. With fixed emissions of CO2 to the atmosphere, ocean fertilization moderately mitigates changes in ocean carbonate chemistry near the ocean surface, but at the expense of further acidifying the deep ocean. Under the SRES A2 CO2 emission scenario, by year 2100 simulated atmospheric CO2, global mean surface pH, and saturation state of aragonite is 965 ppm, 7.74, and 1.55 for the scenario without fertilization and 833 ppm, 7.80, and 1.71 for the scenario with 100-year (between 2000 and 2100) continuous fertilization for the global ocean (For comparison, pre-industrial global mean surface pH and saturation state of
Hutchison, M L; Walters, L D; Avery, S M; Moore, A
To measure the rates of decline of zoonotic agents introduced into heaps of spent bedding and faecal wastes generated by commercially farmed livestock and managed in a similar way to that of a working farm. Livestock isolates of Salmonella, pathogenic Listeria, Campylobacter and Escherichia coli O157 were laboratory cultured and used to inoculate 5 m3 heaps of cattle, sheep or pig wastes mixed with bedding materials. Decline of each of the infectious agents was monitored with time as was the temperature inside each heap. Temperatures of >50 degrees C were typically achieved at the core of the heaps. Pathogen decline was rapid, typically waste from animal pens to a secondary store, and storing them under conditions conducive for increased temperature is a simple and cost-effective treatment for rapidly lowering levels of zoonotic agents in solid farm wastes. This study demonstrates a simple and cheap treatment that can be used to help prevent the spread of zoonotic agents through agricultural environments.
Dec 6, 2010 ... Thesis, University of Basel, Basel, Switzerland. Kerry M, Matthies D, Spillman HH (2000). Reduced fertility and offspring performance in small populations of the declining grassland plants. Primula veris and Gentiana lutea. J. Ecol. 88: 17-30. Khan MA, Stace CA (1999). Breeding relationship in the genus.
Thomas McAvoy; Ryan Mays; Nels Johnson; Scott Salom
Hemlock woolly adelgid (HWA), Adelges tsugae Annand, an invasive insect native to the Pacific Northwest and Asia, is responsible for widespread health decline and mortality of native hemlocks (Tsuga spp.) in the eastern United States. Shading and fertilizer has been found to affect the survival and health of both HWA and...
Soil infertility undermines the agriculture-based livelihoods in Malawi, where it is blamed for poor crop yields and the creation of cycles of poverty. Although technologies and management strategies have been developed to reverse the decline in soil fertility, they are under-used by smallholder
Profitable milk production and genetic improvement in dairy herds depend largely on fertile cows calving annually to initiate a new lactation period. Over the last 30 years, several studies have indicated a decline in the reproductive performance of dairy cows. From the perspectives of many farmers and veterinarians, the ...
There is a growing body of evidence that nutritional habits may have a significant effect on both male and female fertility. Maintenance of normal body mass may be effective in the prevention of infertility resulting from ovulatory disorders. Underweight and, to a larger degree, overweight and/or obesity, are related to the enhanced risk of infertility. Insulin resistance is an important pathogenic mechanism that may impair ovulation. Adequate intake of monounsaturated fatty acids, derived mainly from vegetable fats, as well as avoidance of trans isomers of unsaturated fatty acids which are present in industrially produced cakes and sweets, crisps, fast-foods, powdered soups and hard margarines, may be effective in the prevention of infertility in females. Choice of plant rather than animal sources of proteins, decrease in glycemic load of the diet, use of dietary supplements containing iron and folic acid, could also be beneficial. Avoidance of vitamin B12 deficiency and its supplementation seem to be important in the prevention of early miscarriages. Sufficient intake of antioxidants also promotes female reproductive functions. Free radical processes play an important role in the development of male factor infertility. It was shown that proper intake or supplementation with antioxidants may be effective in its prevention and treatment. Such nutrients as zinc, selenium and folic acid act beneficially on sperm quality. A well-balanced diet seems to play an important role in the prevention of infertility in both sexes.
Alazbih, Nega Mihret; Tewabe, Getachew Nibret; Demissie, Tariku Dejene
The overall decline of fertility in Amhara National Regional State between 2000 and 2011 was the highest in Ethiopia. The aim of the present study was to determine the most significant proximate determinant of fertility change during the last decade in the region using Bongaarts' model. The sources of data were the 2000, 2005, and 2011 Ethiopia Demographic and Health Surveys. The model indices were calculated for each survey. Decomposition of fertility change into components of proximal determinants was also carried out. An index value close to 1 is a negligible inhibiting effect while a large inhibiting effect when the value very closes to 0. The fertility-constraining effect of contraception increased from 0.93 in 2000 to 0.65 in 2011; however, it was lower than the effect of postpartum insusceptibility at all given times. The index of marriage remained unchanged in constraining fertility over the period (0.71 in 2000 and 0.70 in 2011) while the influence of postpartum insusceptibility slightly declined from 0.49 in 2000 to 0.54 in 2011 but was stronger than contraception and marriage. The contribution of contraception was most important in urban areas (0.46 in 2011 from 0.52 in 2005 and 0.64 in 2000); however, in rural areas, it became an important determinant over the period (0.95 in 2000 and 0.69 in 2011). The effect of postpartum insusceptibility in rural areas showed a decreasing trend (0.48 in 2000 and 0.53 in 2011). The index of marriage in rural areas was stable overtime (0.75 in 2000 and 0.73 in 2011) while in urban areas the effect declined from 0.42 in 2000 to 0.65 in 2011. Marriage was the most important proximate determinant of fertility among women with secondary and above education but the impact declined during the period (0.41 in 2000 and 0.61 in 2011). The importance of postpartum insusceptibility in limiting fertility among women with secondary and above education declined overtime (0.77 in 2000 and 0.87 in 2011) whereas the contribution of
Javelin, a Lone Peak Engineering Inc. Company has introduced the SteamRoller(TM) System as a commercial product. The system was designed by Javelin during a Phase II NASA funded small commercial product. The purpose of the invention was to allow automated-feed of flexible ceramic tapes to the Laminated Object Manufacturing rapid prototyping equipment. The ceramic material that Javelin was working with during the Phase II project is silicon nitride. This engineered ceramic material is of interest for space-based component.
For the first time ever an overview and analysis of CEE family policies is conceptualized in this paper. It demonstrates that fertility trends and family policies are a matter of serious concern throughout the region. The following family policy types have been identified: comprehensive family policy model; pro-natalist policies model; temporary male bread-winner model; and conventional family policies model. The majority of family policies in CEE countries suffer from a variety of shortcomings that impede them from generating enhanced family welfare and from providing conditions for cohort fertility to increase. The likely further decline of cohort fertility, or its stagnation, may entail long-term demographic as well as other societal consequences, such as continuous declines in total population numbers, changes in age structures, as well as implications for health and social security costs.
Kouba, A J; Vance, C K; Willis, E L
Amphibian populations in the wild are experiencing massive die-offs that have led to the extinction of an estimated 168 species in the last several decades. To address these declines, zoological institutions are playing an important role in establishing captive assurance colonies to protect species in imminent danger of extinction. Many of the threatened species recently placed into captivity are failing to reproduce before they expire, and maintaining founder populations is becoming a formidable challenge. Assisted reproductive technologies, such as hormone synchronization, gamete storage and artificial fertilization, are valuable tools for addressing reproductive failure of amphibians in captive facilities. Artificial fertilization has been commonly employed for over 60 years in several keystone laboratory species for basic studies in developmental biology and embryology. However, there are few instances of applied studies for the conservation of threatened or endangered amphibian species. In this review, we summarize valuable technological achievements in amphibian artificial fertilization, identify specific processes that need to be considered when developing artificial fertilization techniques for species conservation, and address future concerns that should be priorities for the next decade.
.... 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...
Kieffer, George H.
Issues surrounding the controversial topic of in vitro fertilization and artificial manipulation of reproduction are discussed. The author examines the moral and ethical implications and presents results of a survey of various religious groups. (SA)
Full Text Available ... Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility ... injury? What is a Spinal Cord Injury? SCI Medical Experts People Living With SCI Personal Experiences By ...
... fertilize an egg, sperm must move — wriggling and swimming through a woman's cervix, uterus and fallopian tubes. ... Biology. 2009;47:615. Swerdloff RS, et al. Evaluation of male infertility. http://www.uptodate.com/home. ...
Methods: For this study, the linear mixed model was used to determine factors affecting fertility status of women in ... Variable of interest ... Therefore, the general linear mixed model (LMM) for ... The methods are described in the next section.
Full Text Available ... Experiences by Topic Resources Peer Counseling Blog About Media Donate ... from Hospital to Home Kim Eberhardt Muir, MS Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After ...
Full Text Available ... Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David Chen, ...
Full Text Available ... About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal ... LLC Understanding Spinal Cord Injury About Us Expert Videos Contact Us Personal Experience Videos Blog Videos By ...
Full Text Available ... after a spinal cord injury? play_arrow How does caregiving for your partner often affect romantic relationships? ... mistaken for preeclampsia during pregnancy? play_arrow How does a spinal cord injury affect male fertility? play_ ...
Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik
OBJECTIVE: To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss. DESIGN: Prospective follow-up study. SETTING: Healthy couples recruited throughout Denmark...
Full Text Available ... Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David ...
Luo, Jinping; McGinnis, Lynda K; Carlton, Carol; Beggs, Hilary E; Kinsey, William H
Fertilization triggers rapid changes in intracellular free calcium that serve to activate multiple signaling events critical to the initiation of successful development. Among the pathways downstream of the fertilization-induced calcium transient is the calcium-calmodulin dependent protein tyrosine kinase PTK2b or PYK2 kinase. PTK2b plays an important role in fertilization of the zebrafish oocyte and the objective of the present study was to establish whether PTK2b also functions in mammalian fertilization. PTK2b was activated during the first few hours after fertilization of the mouse oocyte during the period when anaphase resumption was underway and prior to the pronuclear stage. Suppression of PTK2b kinase activity in oocytes blocked sperm incorporation and egg activation although sperm-oocyte binding was not affected. Oocytes that failed to incorporate sperm after inhibitor treatment showed no evidence of a calcium transient and no evidence of anaphase resumption suggesting that egg activation did not occur. The results indicate that PTK2b functions during the sperm-egg fusion process or during the physical incorporation of sperm into the egg cytoplasm and is therefore critical for successful development. Published by Elsevier Inc.
Costa Rica, whose life expectancy was 74 years by 1985, has reached a health level comparable to a developed country. The health achievements of this country are product of political and socioeconomic circumstances as well as of right public health policies. Until about 1970 the features of Costa Rica mortality, although somewhat better than the Latin American average, evolved in a similar way to the rest of the region. In particular, the decades of 1940s and 1950s saw dramatic improvements in life expectancy, thanks mainly to the import of low-cost, high-effectiveness health technologies. In the 1970s, however, Costa Rica departed from a regional pattern of stagnation and managed to close the gap with developed countries in terms of mortality levels. A dramatic decline in the infant mortality rate from 60 to 19 per 1,000 took place in this decade. The main determinants of this breakthrough were health interventions, notably a primary health care program, even though favorable socioeconomic conditions and a reduced fertility also played a role. Ecological data and other evidence suggest that up to three fourths of the mortality decline was accounted for contemporary improvements in public health services, with about 40 percent attributable to primary health care interventions. Furthermore, by targeting interventions on the less privileged population, these interventions had the merit of reducing geographic and socioeconomic differentials in child mortality.
Shakuntala Chhabra; Imran Kutchi
For cancers of reproductive system in women, fertility preservation is complex. Fertility is also affected by therapies, however prevention is possible. Radiotherapy affects gonads, uterus, and subsequent pregnancy outcomes in all ages. However, degree and damage depend on dose, irradiation field, and age at the time of exposure. Ovarian transposition is considered if ovarian involvement is unlikely. Gonadotoxic effects of chemotherapy are related to agent’s type, cumulative doses, age, and o...
Cognitive decline in older persons can be pathologic or occur as a part of the normal aging process. Delirium, depression, and dementia are geriatric syndromes and neurocognitive disorders that are the result of cognitive decline associated with pathology. This overview is a brief guide on cognitive decline and how to identify, manage, and treat associated neurocognitive disorders, including delirium, depression, and dementia. Copyright © 2017 Elsevier Inc. All rights reserved.
Full Text Available ... approach the subject of fertility preservation with their cancer-stricken child? How is the Oncofertility Consortium addressing the fertility preservation needs of children? How do cancer and cancer treatment affect a child's fertility? Why should fertility preservation be a priority ...
Full Text Available ... website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open ... Diagnosed with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation ...
Joffe, M; Key, J; Best, N
BACKGROUND: It is plausible that a couple's ability to achieve the desired number of children is limited by biological fertility, especially if childbearing is postponed. Family size has declined and semen quality may have deteriorated in much of Europe, although studies have found an increase...... rather than a decrease in couple fertility. METHODS: Using four high-quality European datasets, we took the reported time to pregnancy (TTP) as the predictor variable; births reported as following contraceptive failure were an additional category. The outcome variable was final or near-final family size....... Potential confounders were maternal age when unprotected sex began prior to the first birth, and maternal smoking. Desired family size was available in only one of the datasets. RESULTS: Couples with a TTP of at least 12 months tended to have smaller families, with odds ratios for the risk of not having...
Do low fertility and population aging lead to economic decline if couples have fewer children, but invest more in each child? By addressing this question, this article extends previous work in which the authors show that population aging leads to an increased demand for wealth that can, under some conditions, lead to increased capital per worker and higher per capita consumption. This article is based on an overlapping generations (OLG) model which highlights the quantity–quality tradeoff and the links between human capital investment and economic growth. It incorporates new national level estimates of human capital investment produced by the National Transfer Accounts project. Simulation analysis is employed to show that, even in the absence of the capital dilution effect, low fertility leads to higher per capita consumption through human capital accumulation, given plausible model parameters. PMID:20495605
Oliver, Tom H; Isaac, Nick J B; August, Tom A; Woodcock, Ben A; Roy, David B; Bullock, James M
The composition of species communities is changing rapidly through drivers such as habitat loss and climate change, with potentially serious consequences for the resilience of ecosystem functions on which humans depend. To assess such changes in resilience, we analyse trends in the frequency of species in Great Britain that provide key ecosystem functions--specifically decomposition, carbon sequestration, pollination, pest control and cultural values. For 4,424 species over four decades, there have been significant net declines among animal species that provide pollination, pest control and cultural values. Groups providing decomposition and carbon sequestration remain relatively stable, as fewer species are in decline and these are offset by large numbers of new arrivals into Great Britain. While there is general concern about degradation of a wide range of ecosystem functions, our results suggest actions should focus on particular functions for which there is evidence of substantial erosion of their resilience.
Full Text Available The generation of handwriting is a complex neuromotor skill requiring the interaction of many cognitive processes. It aims at producing a message to be imprinted as an ink trace left on a writing medium. The generated trajectory of the pen tip is made up of strokes superimposed over time. The Kinematic Theory of rapid human movements and its family of lognormal models provide analytical representations of these strokes, often considered as the basic unit of handwriting. This paradigm has not only been experimentally confirmed in numerous predictive and physiologically significant tests but it has also been shown to be the ideal mathematical description for the impulse response of a neuromuscular system. This latter demonstration suggests that the lognormality of the velocity patterns can be interpreted as reflecting the behaviour of subjects who are in perfect control of their movements. To illustrate this interpretation, we present a short overview of the main concepts behind the Kinematic Theory and briefly describe how its models can be exploited, using various software tools, to investigate these ideal lognormal behaviors. We emphasize that the parameters extracted during various tasks can be used to analyze some underlying processes associated with their realization. To investigate the operational convergence hypothesis, we report on two original studies. First, we focus on the early steps of the motor learning process as seen as a converging behaviour toward the production of more precise lognormal patterns as young children practicing handwriting start to become more fluent writers. Second, we illustrate how aging affects handwriting by pointing out the increasing departure from the ideal lognormal behaviour as the control of the fine motricity begins to decline. Overall, the paper highlights this developmental process of merging toward a lognormal behaviour with learning, mastering this behaviour to succeed in performing a given task
Plamondon, Réjean; O'Reilly, Christian; Rémi, Céline; Duval, Thérésa
The generation of handwriting is a complex neuromotor skill requiring the interaction of many cognitive processes. It aims at producing a message to be imprinted as an ink trace left on a writing medium. The generated trajectory of the pen tip is made up of strokes superimposed over time. The Kinematic Theory of rapid human movements and its family of lognormal models provide analytical representations of these strokes, often considered as the basic unit of handwriting. This paradigm has not only been experimentally confirmed in numerous predictive and physiologically significant tests but it has also been shown to be the ideal mathematical description for the impulse response of a neuromuscular system. This latter demonstration suggests that the lognormality of the velocity patterns can be interpreted as reflecting the behavior of subjects who are in perfect control of their movements. To illustrate this interpretation, we present a short overview of the main concepts behind the Kinematic Theory and briefly describe how its models can be exploited, using various software tools, to investigate these ideal lognormal behaviors. We emphasize that the parameters extracted during various tasks can be used to analyze some underlying processes associated with their realization. To investigate the operational convergence hypothesis, we report on two original studies. First, we focus on the early steps of the motor learning process as seen as a converging behavior toward the production of more precise lognormal patterns as young children practicing handwriting start to become more fluent writers. Second, we illustrate how aging affects handwriting by pointing out the increasing departure from the ideal lognormal behavior as the control of the fine motricity begins to decline. Overall, the paper highlights this developmental process of merging toward a lognormal behavior with learning, mastering this behavior to succeed in performing a given task, and then gradually
Smith, Nicole K; Madeira, Jody; Millard, Heather R
Women undergoing fertility treatment are likely to report negative changes in sexual function. With the rapid increase in the number of women pursuing in vitro fertilization (IVF), there is a need to better understand how IVF impacts a woman's sexual experiences and quality of life. This study has three purposes: (i) test the psychometric properties of the Sexual Functioning Questionnaire (SFQ) in a sample of U.S. women undergoing IVF; (ii) compare sexual function of women undergoing IVF with a nonclinical sample of U.S. women; and (iii) identify the aspects of sexual function most related to fertility quality of life (FertiQoL). A total of 136 women who had recently undergone or who were currently undergoing IVF completed a web-based, cross-sectional survey about sexual experiences and quality of life. Data were collected on infertility diagnosis, length of infertility, number of IVF cycles, pregnancy, and birth outcomes. Six domains of sexual function as well as the medical impact of IVF were assessed using the SFQ. A validated instrument was used to measure FertiQoL. Reliability analyses for the SFQ indicate sufficiently strong fit (Cronbach's alpha = 0.79 to 0.89). Compared with a nonclinical sample, women undergoing IVF scored significantly lower in sexual interest, desire, orgasm, satisfaction, sexual activity, and overall sexual function (P Women undergoing IVF may be at particular risk for sexual problems. Sexual function issues may markedly impact overall quality of life during fertility treatment and should be addressed as an important component of comprehensive care. © 2015 International Society for Sexual Medicine.
Germany is a low-fertility country with a rapidly ageing population, and will remain so for the foreseeable future. There are several reasons for this trend. Germany is among the countries with the highest rates of childlessness in the world, and childlessness has become widely accepted. This is illustrated by changes in living arrangements. A broad range of living arrangements has been added to the basic model of marriage with children; namely, single living, non-marital cohabitation, lone p...
Ide, Mark; Harris, Marina; Stevens, Annette; Sussams, Rebecca; Hopkins, Viv; Culliford, David; Fuller, James; Ibbett, Paul; Raybould, Rachel; Thomas, Rhodri; Puenter, Ursula; Teeling, Jessica; Perry, V. Hugh; Holmes, Clive
Periodontitis is common in the elderly and may become more common in Alzheimer’s disease because of a reduced ability to take care of oral hygiene as the disease progresses. Elevated antibodies to periodontal bacteria are associated with an increased systemic pro-inflammatory state. Elsewhere raised serum pro-inflammatory cytokines have been associated with an increased rate of cognitive decline in Alzheimer’s disease. We hypothesized that periodontitis would be associated with increased dementia severity and a more rapid cognitive decline in Alzheimer’s disease. We aimed to determine if periodontitis in Alzheimer’s disease is associated with both increased dementia severity and cognitive decline, and an increased systemic pro inflammatory state. In a six month observational cohort study 60 community dwelling participants with mild to moderate Alzheimer’s Disease were cognitively assessed and a blood sample taken for systemic inflammatory markers. Dental health was assessed by a dental hygienist, blind to cognitive outcomes. All assessments were repeated at six months. The presence of periodontitis at baseline was not related to baseline cognitive state but was associated with a six fold increase in the rate of cognitive decline as assessed by the ADAS-cog over a six month follow up period. Periodontitis at baseline was associated with a relative increase in the pro-inflammatory state over the six month follow up period. Our data showed that periodontitis is associated with an increase in cognitive decline in Alzheimer’s Disease, independent to baseline cognitive state, which may be mediated through effects on systemic inflammation. PMID:26963387
Full Text Available A loss of sperm viability and functionality during sperm transfer and storage within the female reproductive tract can have important fitness implications by disrupting fertilization and impairing offspring development and survival. Consequently, mechanisms that mitigate the temporal decline in sperm function are likely to be important targets of selection. In many species, ovarian fluid is known to regulate and maintain sperm quality. In this paper, we use the guppy Poecilia reticulata, a highly polyandrous freshwater fish exhibiting internal fertilization and sperm storage, to determine whether ovarian fluid (OF influences the decline in sperm viability (the proportion of live sperm in the ejaculate over time and whether any observed effects depend on male sexual ornamentation. To address these questions we used a paired experimental design in which ejaculates from individual males were tested in vitro both in presence and absence of OF. Our results revealed that the temporal decline in sperm viability was significantly reduced in the presence of OF compared to a saline control. This finding raises the intriguing possibility that OF may play a role in mediating the decline in sperm quality due to the deleterious effects of sperm ageing, although other possible explanations for this observation are discussed. Interestingly, we also show that the age-related decline in sperm viability was contingent on male sexual ornamentation; males with relatively high levels of iridescence (indicating higher sexual attractiveness exhibited a more pronounced decline in sperm viability over time than their less ornamented counterparts. This latter finding offers possible insights into the functional basis for the previously observed trade-off between these key components of pre- and postcopulatory sexual selection.
Loraine, J A
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
Debra A. Patla; Charles R. Peterson; Paul Stephen Corn
We conduct long-term amphibian monitoring in Yellowstone National Park (YNP) (1) and read McMenamin et al.'s article (2) with interest. This study documents decline in the extent of seasonal wetlands in the Lamar Valley of YNP during extended drought, but the conclusion, widely reported in the media, of "severe declines in 4 once-common amphibian species,...
Kudesia, Rashmi; Talib, Hina J; Pollack, Staci E
To provide a detailed summary of fertility awareness counseling pearls for healthy teens and those with fertility-relevant comorbidities, and to assist providers in offering such counseling to adolescents and young adult women. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: Comprehensive literature review of English-language studies relating to fertility in pediatric and adolescent female patients (ages 13-21 years), and evidence-based dialogue guide. The literature indicates that although adolescents are interested in discussing sexuality and reproduction, this is commonly overlooked during the standard office medical visit. As a result, adolescents often turn to less reliable sources and hold a variety of reproductive misconceptions and a sense of lack of control over future fertility. We found no studies that examined the routine provision of fertility awareness counseling with healthy adolescents. There are a multitude of specific gynecologic and medical conditions that have ramifications for fertility. We detail these comprehensively, and provide a dialogue guide to assist with fertility awareness counseling for the female adolescent, containing specific information and indications for referral. Providers caring for adolescent girls have the opportunity to enhance fertility awareness as part of a larger reproductive health conversation that adolescents desire, and from which they might benefit. Identifying potential future fertility issues, understanding age-related fertility decline, and aiding in health optimization before future conception might empower the adolescent to make informed reproductive decisions. We provide an algorithm to use with adolescents to discuss the "right time, right weight, right way" to pursue childbearing. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.
Rašević Mirjana M.
Full Text Available The 1990s represent an exceptionally complex period for the population of Serbia. In addition to the impact of long-term factors, various tumultuous events affected its demographic development, such as breaking apart of former Yugoslavia, armed conflicts in the neighboring countries, sanctions imposed by the international community, social changes (transition transformation or regression, deep economic crisis, collapse of social stratification political problems, institutional crisis, and NATO military intervention. Maladjustment to the changed system of values and norms, lower level of personal attainment, feeling of insecurity, and living under permanent stress are the main features of life at an individual psychological level. Deprivation or living at the subsistence level are the main elements of the economic cost sustained by the majority of the population. How have these changes affected an individual's decision to have children? The analysis of futility indicators points to an obvious decline in the number of births across low fertility regions of Serbia. Also, the analysis has raised the question why the decline in population fertility in the low fertility regions was not even higher, bearing in mind the experiences undergone by the countries with economy in transition as well as the depth of the crisis in society. In that sense several factors come to mind. The most important are the universality of marriage socio-psychological investigations confirmed domination of the traditional character or mentality in Serbia during the 1990s, and the government’s approach to the issue of fertility improved during this time. Besides demographic needs were carefully taken into account in all amendments to the old and formulation of the new measures in the area of social policy. Mention should be made of measures ensuring employment rights of women and their entitlement to maternity leave, maternity pay, and provision of institutionalized care for
Leridon, H; Slama, R
Over the past decades, the proportion of couples who resort to infertility treatment has tremendously increased, and fertility (the final number of children) sharply declined. We explored the roles of two potential causes of these trends: a temporal decline in the couples' fecundability and a postponement of age at initiation of pregnancy attempts. We conducted a Monte-Carlo simulation for the reproductive history of 100,000 women based on the fertility and socio-demographic characteristics of the 1968 birth cohort in France. Declines in fecundability of various amplitudes have been implemented, as well as increases in the distribution of age at initiation of pregnancy attempts. A decline in fecundability by 15% implied a decrease in fertility by 4%, and an increase in the proportion of couples eligible for infertility treatments by 73%. An increase in the mean age at initiation of first pregnancy attempt by 2.5 years from 25 years entailed a decrease by 5% in fertility and an increase by 32% in the proportion of couples eligible for infertility treatments. A relatively important decrease in fecundability and an increase by 2.5 years in age at first pregnancy attempt are likely to have only a limited impact on fertility. However, they may have a large impact on the proportion of involuntarily infertile couples, likely to resort to assisted reproduction techniques.
Fishman, Michael A; Stone, Lewi; Lotem, Arnon
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.
Full Text Available Background: The paper explores the mechanisms of the European fertility transition in northern Italy by social group. Objective: Our objective is to understand when and in which sectors of a rural society the reduction of family size began. We focus on Emilia-Romagna, a region that in the 1990s had the lowest fertility level in Italy. The core purpose of this paper is the analysis of socioeconomic status (SES fertility differentials, especially between rural sharecroppers and landless rural workers, as well as other non-agricultural groups. Methods: Our analysis focuses on the reproductive histories of marriage cohorts in the years 1900‒1940. We perform a micro-level statistical analysis of legitimate births of parity 1+. Results: In this period fertility decline has just begun, and shows a strong decline in the post-WWI marriage cohorts. Although nonagricultural groups lead the downward trend in family size, the role of socioeconomic status means that the path of sharecropper households is atypical. Conclusions: The fertility transition proceeds by means of spacing and stopping, testifying to a new attitude towards birth control, which agricultural and nonagricultural social groups adopted in different ways. Usually, the decline in fertility progresses from nonagricultural to rural classes. In the rural world the path is inverted, going from the lower to the upper groups. Contribution: The paper contributes to the debate on the links between socioeconomic status and fertility transition in Italy. It shows that the link between household economy and control of fertility is specific to SES groups, which can follow atypical paths, compared to the known reference model. The use of microdemographic data provides evidence for the hypothesis that the fertility transition can be shaped by the specific social and economic characteristics of population subgroups.
Counter to expectation based on the experience of developed nations, in Iran the increase of oil revenue from 1952 to 1975 was not accompanied by a decline in the fertility rate. To identify possible determinants of fertility behavior, the following hypotheses were tested: 1) developmental factors such as urbanization, high school or higher education of females, types of occupation and female labor force participation, have a direct negative impact; 2) the developmental variables have an indirect negative effect on fertility through the mean age at first marriage; 3) mean age at first marriage has a direct negative effect on fertility; and 4) in the provinces (Central, Khuzestan, Esfahan, E. Azarbijan) where large amounts of oil revenue was allocated, the fertility rate is lower than the fertility rate in other provinces where small amounts of oil revenue were distributed. Among developmental variables, high school and college education of females aged 15-29 as well as mean age at first marriage of females, or, lower proportion of married females age 20-24 were found to be important factors in depressing the fertility rate.
Günther, Isabel; Harttgen, Kenneth
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.
Dorvlo, Atsu S S; Bakheit, Charles S; Al-Riyami, Asya; Morsi, Magdi; Al-Adawi, Samir
Objective: To examine the relation between age, education, residence and fertility rate and change in fertility rate between 1994/95 and 1999/2000. Methods: The data for the study was extracted from the Oman National Health Survey, 2000. The birth histories data was used to extract data on woman years and births in the periods 1990 to 1994 and 1995 to 2000. Results: The marital fertility rate in 1999/2000 was 7.12 births. The rates for rural and urban dwellers were 8.07 and 6.75 respectively in 1999/2000. Corresponding rates in 1994/95 (8.65, 8.30 and 9.69 respectively) were significantly higher than those in 1999/2000 for all categories, indicating a reduction in rates. In both periods the higher the education level of the mother the lower her fertility. Conclusion: Education was a strong determinant of fertility. This study confirms that the higher the education of the woman the lower her fertility and that fertility is on the decline in Oman. PMID:21748133
Medeiros,Reinaldo F.; Pereira,Walter E.; Rodrigues,Rummenigge de M.; Nascimento,Ronaldo do; Suassuna,Janivan F.; Dantas,Tony A. G.
ABSTRACTStrawberry (Fragaria x ananassa) is a crop that has rapid growth and is highly influenced by fertilization. Due to its development speed, the plant needs to absorb sufficient macronutrients in order to meet its demand. The objective of this research was to evaluate growth and yield of strawberry under different doses of nitrogen (N), phosphorus (P) and potassium (K) fertilization. The treatments, using Box's central composite design, were distributed in randomized blocks with four rep...
Chotirmall, S H
Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to Irish CF males. A Descriptive Study utilizing prospective coded questionnaires was mailed to a male CF cohort (n=50). Sections included demographics, fertility knowledge & investigation. Response rate was 16\\/50 (32%). All were aware that CF affected their fertility. More than two-thirds (n=11) were able to provide explanations whilst only one-third (n=5) provided the correct explanation. Significant numbers stated thoughts of marriage and a future family. Half have discussed fertility with a healthcare professional (HCP). Mean age of discussion was 21.9 years. One third preferred an earlier discussion. The commonest first source for information was written material which was also the preferred source. Three-quarters requested further information preferring again, written material. Significant gaps in sex education of Irish CF males exist. Discussion should be initiated by HCPs and centre-directed written material devised to address deficiencies.
Cabler, Stephanie; Agarwal, Ashok; Flint, Margot; du Plessis, Stefan S
The obesity pandemic has grown to concerning proportions in recent years, not only in the Western World, but in developing countries as well. The corresponding decrease in male fertility and fecundity may be explained in parallel to obesity, and obesity should be considered as an etiology of male fertility. Studies show that obesity contributes to infertility by reducing semen quality, changing sperm proteomes, contributing to erectile dysfunction, and inducing other physical problems related to obesity. Mechanisms for explaining the effect of obesity on male infertility include abnormal reproductive hormone levels, an increased release of adipose-derived hormones and adipokines associated with obesity, and other physical problems including sleep apnea and increased scrotal temperatures. Recently, genetic factors and markers for an obesity-related infertility have been discovered and may explain the difference between fertile obese and infertile obese men. Treatments are available for not only infertility related to obesity, but also as a treatment for the other comorbidities arising from obesity. Natural weight loss, as well as bariatric surgery are options for obese patients and have shown promising results in restoring fertility and normal hormonal profiles. Therapeutic interventions including aromatase inhibitors, exogenous testosterone replacement therapy and maintenance and regulation of adipose-derived hormones, particularly leptin, may also be able to restore fertility in obese males. Because of the relative unawareness and lack of research in this area, controlled studies should be undertaken and more focus should be given to obesity as an etiolgy of male infertility.
Grynberg, Michaël; Bidet, Maud; Benard, Julie; Poulain, Marine; Sonigo, Charlotte; Cédrin-Durnerin, Isabelle; Polak, Michel
Premature ovarian insufficiency is a relatively rare condition that can appear early in life. In a non-negligible number of cases the ovarian dysfunction results from genetic diseases. Turner syndrome (TS), the most common sex chromosome abnormality in females, is associated with an inevitable premature exhaustion of the follicular stockpile. The possible or probable infertility is a major concern for TS patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The severely reduced follicle pool even during prepubertal life represents the major limit for fertility preservation and is the root of numerous questions regarding the competence of gametes or ovarian tissue crybanked. In addition, patients suffering from TS show higher than usual rates of spontaneous abortion, fetal anomaly, and maternal morbidity and mortality, which should be considered at the time of fertility preservation and before reutilization of the cryopreserved gametes. Apart from fulfillment of the desire of becoming genetic parents, TS patients may be potential candidates for egg donation, gestational surrogacy, and adoption. The present review discusses the different options for preserving female fertility in TS and the ethical questions raised by these approaches. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Warren, C W
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.
Localization of Determinants of Fertility through Measurement Adaptations in Developing-Country Settings: The Case of Iran Comment on “Analysis of Economic Determinants of Fertility in Iran: A Multilevel Approach”
Full Text Available Studies investigating fertility decline in developing countries often adopt measures of determinants of fertility behavior developed based on observations from developed countries, without adapting them to the realities of the study setting. As a result, their findings are usually invalid, anomalous or statistically non-significant. This commentary draws on the research article by Moeeni and colleagues, as an exemplary work which has not adapted measures of two key economic determinants of fertility behavior, namely gender inequality and opportunity costs of childbearing, to the realities of Iran’s economy. Measurement adaptations that can improve the study are discussed.
Localization of determinants of fertility through measurement adaptations in developing-country settings: The case of Iran: Comment on "Analysis of economic determinants of fertility in Iran: a multilevel approach".
Studies investigating fertility decline in developing countries often adopt measures of determinants of fertility behavior developed based on observations from developed countries, without adapting them to the realities of the study setting. As a result, their findings are usually invalid, anomalous or statistically non-significant. This commentary draws on the research article by Moeeni and colleagues, as an exemplary work which has not adapted measures of two key economic determinants of fertility behavior, namely gender inequality and opportunity costs of childbearing, to the realities of Iran's economy. Measurement adaptations that can improve the study are discussed.
Middleton, Jennifer L; Langmuir, Charles H; Mukhopadhyay, Sujoy; McManus, Jerry F; Mitrovica, Jerry X
.... Mir sediments reveal sixfold to eightfold increases in hydrothermal iron and copper deposition during the Last Glacial Maximum, followed by a rapid decline during the sea level rise associated with deglaciation...
In Nigeria organic fertilizers are being developed from organic and farm wastes and these can be fortified with inorganic fertilizer. Therefore eight fertilizer treatments namely:(1) control (no fertilizer), (2) Pacesetter Grade B organic fertilizer (PGB) at 3 t/ha 100 %, (3) 300 kg/ha NPK fertilizer, (4) PGB + NPK fertilizer (75 : 25), ...
Matsuda, Y.; Tobari, I.; Yamada, T. (National Inst. of Radiological Sciences, Chiba (Japan))
The frequency of in vitro fertilization of mouse eggs using sperm obtained weekly (for 1-9 weeks) from epididymis after testicular X-irradiation (200 rad) was observed. The sperm concentrations for insemination were 100, 200 and 300/mm/sup 3/. The number of fertilized eggs seemed to remain constant almost at control level (90-98%) until the 4th week after X-irradiation. Thereafter, the number declined to reach a minimum level (about 30-50%) in the 6th week; they then recovered completely in the 8th week. This tendency was found at all sperm concentrations used. This result indicates that the most sensitive stage for the fertilization capacity of sperm to X-rays was the early spermatocytes or the late spermatogonia. The high radiosensitivity of the fertilization capacity of sperm irradiated during the early-spermatocyte to late-spermatogonial stage, corresponded well with the rate of induction of sperm abnormalities and spermatogenetic cell killing. The in vitro fertilization rate was not restored by an increase in sperm concentration at insemination; it is, therefore, likely that the in vitro fertilization frequency depends on the proportion of sperm with abnormal morphology and abnormal fertilization ability, and sperm number seems to have hardly any influence on the fertilization rate, as far as the in vitro fertilization experiment is concerned.
Frazier, A.W.; Dillard, E.F.; Thrasher, R.D.; Waerstad, K.R.; Hunter, S.R.; Kohler, J.J.; Scheib, R.M.
This bulletin is a compilation of crystallographic data collected at NFERC on 450 fertilizer-related compounds. In TVA's fertilizer R and D program, petrographic examination, XRD, and infrared spectroscopy are combined with conventional chemical analysis methods in identifying the individual compounds that occur in fertilizer materials. This handbook brings together the results of these characterization studies and supplemental crystallographic data from the literature. It is in one-compound-per-page, loose-leaf format, ordered alphabetically by IUPAC name. Indexes provided include IUPAC name, formula, group, alternate formula, synonyms, x-ray data, optical data. Tables are given for solids, compounds in commercial MAP and DAP, and matrix materials in phosphate rock.
Restrepo, B; Cardona-Maya, W
To evaluate the relation between antisperm antibodies (ASA) and human fertility by reviewing the scientific literature of the last 45 years. We carried out a review of scientific literature about antisperm antibodies and infertility published in spanish or english in databases as Pubmed, Medline, Scielo, some books and another gray literature include information related to this review and that is published in the last 45 years. Infertile couples suffer infertility by immunological mechanisms mainly by the presence of antisperm antibodies ASA in blood, semen or cervicovaginal secretions; the formation of ASA in men and women may be associated with disturbance in immunomodulatory mechanisms that result in functional impairment of sperm and thus its inability to fertilize the oocyte. Immunological infertility caused by ASA is the result of interference of these antibodies in various stages of fertilization process, inhibiting the ability of interaction between sperm and oocyte. Copyright © 2012 AEU. Published by Elsevier Espana. All rights reserved.
Cortes, D; Thorup, J M; Lindenberg, S
PURPOSE: We evaluated whether adult fertility potential was better when unilateral orchiopexy was done at ages 2 to 6 years or later, and we identified those at risk for infertility. MATERIALS AND METHODS: Unilateral orchiopexy was performed simultaneously with testicular biopsy in 11 patients 2...... similar fertility potentials were found in adulthood. Five of the 65 patients (7.7%, 95% confidence limits 2.5 to 17%) may experience infertility, representing 33% of both groups with less than 1% of the age matched number of spermatogonia per tubular transverse section (approximately no germ cells......) in the biopsy specimen at orchiopexy. CONCLUSIONS: Between ages 2 and 12 years the timing of unilateral orchiopexy may vary without an effect on subsequent fertility potential. When biopsy at surgery lacks germ cells, there is an approximately 33% age independent risk of subsequent infertility. Otherwise...
Collas, P; Barona, T; Poccia, D L
Fertilization in the sea urchin is accompanied by rapid reorganization of the egg endoplasmic reticulum (ER). ER-derived vesicles contribute to one of three classes of membranes used in assembling the male pronuclear envelope in vitro. We provide here biochemical evidence for the rearrangement of sea urchin egg cytoplasmic membrane domains at fertilization up to the first mitosis, with respect to two nuclear envelope markers, lamin B and lamin B receptor (LBR), using purified vesicles prepared from homogenates fractionated by floatation on sucrose gradients. In unfertilized eggs, immunoprecipitation data indicate that most of lamin B and LBR are localized in the same vesicles but do not interact. By 3 min post-fertilization, both proteins are more widely distributed across the gradients and by 12 min most of lamin B and LBR are localized in vesicles of different densities. This partitioning is maintained throughout S phase. At mitosis, most lamin B and LBR remain in distinct vesicles, while a small proportion of lamin B and LBR, likely derived from the disassembled nuclear envelope, associate in a minor subset of vesicles. The results illustrate a dynamic reorganization of egg cytoplasmic membranes at fertilization, and the establishment of distinct membrane domains enriched in specific nuclear envelope markers during the first cell cycle of sea urchin development. Additionally, we demonstrate that male pro-nuclear membrane assembly occurs only when both cytosol and membranes originate from fertilized but not unfertilized eggs, suggesting that fertilization-induced membrane rearrangements contribute to the ability of the egg to assemble the male pronuclear envelope.
Full Text Available In this paper we revisit the issue of aggregate output decline that took place in the early transition period. We propose an alternative explanation of output decline that is applicable to Central- and Eastern-European countries. In the first part of the paper we develop a simple dynamic general equilibrium model that builds on work by Gomulka and Lane (2001. In particular, we consider price liberalization, interpreted as elimination of distortionary taxation, as a trigger of the output decline. We show that price liberalization in interaction with heterogeneous adjustment costs and non-employment benefits lead to aggregate output decline and surge in wage inequality. While these patterns are consistent with actual dynamics in CEE countries, this model cannot generate output decline in all sectors. Instead sectors that were initially taxed even exhibit output growth. Thus, in the second part we consider an alternative general equilibrium model with only one production sector and two types of labor and distortion in a form of wage compression during the socialist era. The trigger for labor mobility and consequently output decline is wage liberalization. Assuming heterogeneity of workers in terms of adjustment costs and non-employment benefits can explain output decline in all industries.
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.
Jain, Anrudh K; Ross, John A
In many developing countries, fertility has declined steadily in recent decades, while the average strength of family planning programs has increased and social conditions have improved. However, it is unclear whether the synergistic effect of family planning programs and social settings on fertility, first identified in the 1970s, still holds. Data from 40 developing countries in which Demographic and Health Surveys were conducted in 2003-2010 were used to examine associations among socioeconomic conditions, family planning program effort strength and fertility. Cross-tabulations and multiple regression analyses were conducted. Variation among countries in scores on the Family Planning Program Effort Index, but not on the Human Development Index, has diminished since the 1970s. On average, fertility levels were lower among countries with better social settings or stronger family planning programs than among those with poorer settings or weaker programs; they were lowest in the presence of both good social settings and strong programs. In addition, fertility was positively associated with infant mortality and negatively associated with female education, but not associated with poverty. About half of the 2.3-birth difference in fertility between countries in Sub-Saharan Africa and those elsewhere can be attributed to differences in program efforts and social settings. Policies focused on improving levels of female education, reducing infant mortality and improving family planning services can be expected to have mutually reinforcing effects on fertility decline.
Full Text Available Purpose: Reports of business failure elicit various reactions, while research in this domain often appears to be limited by a lack of access to information about failure and by the negativity that surrounds it. Those who have experienced failure do not readily talk about it, or they disappear from the radar screen of researchers. Yet failure is preceded by decline which, when focused on strategically, can reduce eventual failures if early action is taken. The main purpose of this study is to develop a conceptual framework or typology of the drivers and moderators of business decline. Design/methodology/approach: After applying the "grounded theory" approach to the academic literature on decline and failure, a conceptual framework for the variables that drive and moderate business decline is proposed. Findings: The study proposes that decline has three core drivers, three peripheral drivers and four moderators. The core drivers identified are: resource munificence; leadership as origin; and causality (strategic versus operational origin of decline. The three peripheral drivers are: unique preconditions; continuous decisions impact; and extremes dichotomy. The study describes four moderators of the drivers: life cycle stage; stakeholder perspective; quantitative versus qualitative nature of signs and causes; and finally the age and size effects. Research limitations/implications: The proposed conceptual framework is based on literature only, although it has found support during discussions with practitioners. It is proposed to readers of this journal for scrutiny and validation. Practical implications: Strategists need to understand what drives decline in order to act timeously; practitioners who have an insight into the moderators with their impacts could make better decisions in response to decline in organisations and possibly avoid business failure. Originality/Value: Understanding business decline is still a huge theoretical challenge, which
Bostofte, E; Bagger, P; Michael, A
OBJECTIVE: To develop a fertility prognosis model for infertile couples. DESIGN: Prospective follow-up study. PARTICIPANTS: In the period November 30, 1977 to June 1, 1985, 321 consecutive couples were investigated for infertility at Hvidovre University Hospital. Investigation of the female...... MEASURE: The Cox regression model was used to predict the time required to conceive based on informations provided by fertility investigations. RESULTS: Three of 16 prognostic variables (the period of infertility, the female infertility factor, and the P-test) possess significant prognostic information...
Horgan, R P
Hysterectomy is one of the most common gynaecological surgical procedures performed but there appears to be a decline in the performance of this procedure in Ireland in recent times. We set out to establish the extent of the decline of hysterectomy and to explore possible explanations. Data for hysterectomy for benign disease from Ireland was obtained from the Hospital In-Patient Enquiry Scheme (HIPE) section of the Economic and Social Research Institute for the years 1999 to 2006. The total number of hysterectomies performed for benign disease showed a consistent decline during this time. There was a 36% reduction in the number of abdominal hysterectomy procedures performed.
Driver, Todd H.; Shlipak, Michael G.; Katz, Ronit; Goldenstein, Leonard; Sarnak, Mark J.; Hoofnagle, Andrew N.; Siscovick, David S.; Kestenbaum, Bryan; de Boer, Ian H.; Ix, Joachim H.
Background Among populations with established chronic kidney disease (CKD), metabolic acidosis is associated with more rapid progression of kidney disease. The association of serum bicarbonate concentrations with early declines in kidney function is less clear. Study Design Retrospective cohort study. Setting & Participants 6380 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) with a baseline estimated glomerular filtration rate (eGFR) >60 mL/min/1.73m2 using the CKD-EPI (CKD Epidemiology Collaboration) creatinine–cystatin C equation. Predictors Serum bicarbonate concentrations. Outcomes Rapid kidney function decline (eGFR decline >5% per year) and incident reduced eGFR (eGFRkidney function decline, and 487 had incident reduced eGFR during follow-up. Each 1-SD lower baseline bicarbonate concentration was associated with 12% higher adjusted odds of rapid kidney function decline (95% CI, 6%–20%) and higher risk of incident reduced eGFR (adjusted incidence rate ratio, 1.11; 95% CI, 1.03–1.20) in models adjusting for demographics, baseline eGFR, albuminuria, and CKD risk factors. The OR for the associations of bicarbonate kidney function decline, and the incidence rate ratio was 1.16 (95% CI, 0.83–1.62) for incident reduced eGFR. Limitations Etiology of metabolic acidosis cannot be determined in this study. Conclusions Lower serum bicarbonate concentrations are independently associated with rapid kidney function decline independent of eGFR or albuminuria in community-living persons with a baseline eGFR >60 mL/min/1.73 m2. If confirmed, our findings suggest that metabolic acidosis may indicate either early kidney disease that is not captured by eGFR or albuminuria, or may have a causal role in the development of an eGFR <60 mL/min/1.73 m2. PMID:24953891
Full Text Available The study aims to determine fertility status of the soil after organic paddy experiments using kinds and doses of organic fertilizers. Experiment was conducted at greenhouse laboratory in Faculty of Agriculture Sebelas Maret University Surakarta. Experimental design used completely randomized design with 9 kinds of treatment was replicated 3 times. Experiments were the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations that are based on fulfilling nutrient requirements of 120 kg N ha-1. Result shows that the use of cow manure, Azolla fertilizers and Azolla inoculum had no effect on changes of soil fertility status. Soil fertility status was not significantly correlated with cow manure (0,16ns, Azolla fertilizer (0,26ns and Azolla inoculum (0,16ns. Average of final soil fertility status included fertile category, which was similar as the initial soil fertility status. Average of final soil properties of treatment but nevertheless was relatively higher than in no treatment, indicating the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations had greater impact to soil properties. Cow manure despite increased available K2O and dry grain, but it did not significantly increase the soil fertility status from fertile to very fertile. This was presumably due to the relatively short experiment period, only one planting season had not given significant effect to soil properties. Implication of this study is the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations although did not increase the soil fertility status but could maintain soil fertility status as the initial conditions before planting.
... presenting bank may offer evidence that the drawer's signature was authentic or was authorized. (4) Checks... contain a material defect or alteration. (c) Procedures for filing a protest. A declination protest must...
Full Text Available During the last several years, a significant decline of different forests in Serbia was recorded. The decline is more widespread in conifer stands, but occurence of decline was recorded in broadleaved forest stands as well. These declines are the result of abiotic, biotic and anthropogenic factors. According to the studies performed so far in Serbia, the predisposing factor were droughts during the 2012 and 2013 vegetation periods that caused physiological weakness of the trees. Among the biotic factors, the most important are fungi (mainly root rot, but rot fungi, and needle diseases and insects (bark beetles in conifer species and defoliators in broadleaved species. [Projekat Ministarstva nauke Republike Srbije, br. TR 37008 i br. TR 31070
Mathar, Helle; Fastholm, Pernille; Hansen, Ida Rode
obligations or priorities. The problems with the referral of patients relate to different areas: the referring health professional's conviction and commitment, and the patients' understanding of the referral. It seems that various transport problems cause decline, for example long distance to the PR centre...... through a systematic literature search in relevant databases. In these six studies, 65 persons were identified as decliners of PR. Four themes were identified from these studies. RESULTS: The themes identified were as follows: the referral process, transport problems, perception of health and other...... of PR causing decline. CONCLUSION: The studies included show patients' rational accounts and reflections on declining PR. The included studies tend to describe accounts for deselection of PR in relation to the preferences and beliefs of the patients rather than including the social and economic...
.... ( We are all Americans now. ) Since then, polls conducted by the U.S. Government and respected private firms have revealed a precipitous decline in favorability toward the United States and its foreign policy...
Xu, Zhi-Yu; Wang, Xuan-Yi; Liu, Chang-Qing; Li, Yang-Ting; Zhuang, Fang-Chen
The objective of the study was to identify the protective factors for the rapid decline in the risk of hepatitis A virus (HAV) infection in China between 1990 and 2006. Results of serological follow-up and data on annual hepatitis A incidence were analysed and correlated with economic growth and HAV vaccine output during the same period. In conclusion, both HAV vaccination and changing lifestyles associated with the booming economy contributed to the rapid risk decline. Changing lifestyles played a major role in the decline especially in the areas with booming economy.
Driver, Todd H; Shlipak, Michael G; Katz, Ronit; Goldenstein, Leonard; Sarnak, Mark J; Hoofnagle, Andrew N; Siscovick, David S; Kestenbaum, Bryan; de Boer, Ian H; Ix, Joachim H
Among populations with established chronic kidney disease (CKD), metabolic acidosis is associated with more rapid progression of kidney disease. The association of serum bicarbonate concentrations with early declines in kidney function is less clear. Retrospective cohort study. 5,810 participants in the Multi-Ethnic Study of Atherosclerosis (MESA) with a baseline estimated glomerular filtration rate (eGFR) > 60mL/min/1.73 m(2) using the CKD-EPI (CKD Epidemiology Collaboration) creatinine-cystatin C equation. Serum bicarbonate concentrations. Rapid kidney function decline (eGFR decline > 5% per year) and incident reduced eGFR (eGFR bicarbonate concentration was 23.2 ± 1.8mEq/L. 1,730 (33%) participants had rapid kidney function decline, and 487 had incident reduced eGFR during follow-up. Each 1-SD lower baseline bicarbonate concentration was associated with 12% higher adjusted odds of rapid kidney function decline (95% CI, 6%-20%) and higher risk of incident reduced eGFR (adjusted incidence rate ratio, 1.11; 95% CI, 1.03-1.20) in models adjusting for demographics, baseline eGFR, albuminuria, and CKD risk factors. The OR for the associations of bicarbonate level bicarbonate concentrations are associated independently with rapid kidney function decline independent of eGFR or albuminuria in community-living persons with baseline eGFR > 60 mL/min/1.73 m(2). If confirmed, our findings suggest that metabolic acidosis may indicate either early kidney disease that is not captured by eGFR or albuminuria or may have a causal role in the development of eGFR < 60 mL/min/1.73 m(2). Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Chakraborty, Subhendu; Tiwari, P. K.; Sasmal, S. K.; Misra, A. K.; Chattopadhyay, Joydev
The increasing occurrence of algal blooms and their negative ecological impacts have led to intensified monitoring activities. This needs the proper identification of the most responsible factor/factors for the bloom formation. However, in natural systems, algal blooms result from a combination of factors and from observation it is difficult to identify the most important one. In the present paper, using a mathematical model we compare the effects of three human induced factors (fertilizer input in agricultural field, eutrophication due to other sources than fertilizers, and overfishing) on the bloom dynamics and DO level. By applying a sophisticated sensitivity analysis technique, we found that the increasing use of fertilizers in agricultural field causes more rapid algal growth and decreases DO level much faster than eutrophication from other sources and overfishing. We also look at the mechanisms how fertilizer input rate affects the algal bloom dynamics and DO level. The model can be helpful for the policy makers in determining the influential factors responsible for the bloom formation.
Presented is a mathematical model of single-product economy describing a nominal economic growth and a nominal economic decline. Based on the model of economic dynamics, policies handling the gravity of the secular stagnation are furnished. First, transition of the secular stagnation into the secular decline is to be prevented. Second, a two-stage economic policy against the secular stagnation should be entertained. The first stage is to promote a policy of advancing the additional demand for...
Jay R. Law; Ross Melick; Charly Studyvin; James R. Steinman
In the 1980s, following extreme winters in the late 1970s and severe droughts in 1976, 1980, and 1983, dead and dying scarlet and black oaks were found on 185,000 acres of the Mark Twain National Forest. That decline event was linked to environmental stresses (Law and Gott 1987). Severe oak decline is now affecting an estimated 500,000 acres on the Mark Twain. High-...
Cardoso, I.M.; Kuyper, T.W.
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
Heinecke, J W; Shapiro, B M
Partially reduced oxygen species are toxic, yet sea urchin eggs synthesize H2O2 in a "respiratory burst" at fertilization, as an extracellular oxidant to crosslink their protective surface envelopes. To study the biochemical mechanism for H2O2 production, we have isolated an NADPH-specific oxidase fraction from homogenates of unfertilized Strongylocentrotus purpuratus eggs that produces H2O2 when stimulated with Ca2+ and MgATP2-. Concentrations of free Ca2+ previously implicated in regulation of egg activation modulate the activity of the oxidase. Inhibitors were used to test the relevance of this oxidase to the respiratory burst of fertilization. Procaine, two phenothiazines, and N-ethylmaleimide (but not iodoacetamide) inhibited H2O2 production by the oxidase fraction and oxygen consumption by activated eggs. The ATP requirement suggested that protein kinase activity might regulate the respiratory burst of fertilization; consonant with this hypothesis, H-7 and staurosporine were inhibitory. The respiratory burst oxidase of fertilization is an NADPH:O2 oxidoreductase that appears to be regulated by a protein kinase; although it bears a remarkable resemblance to the neutrophil oxidase, unlike the latter it does not form O2- as its initial product.
Tesfaye Regassa & Mesganaw Fantahun. Sci. Technol. Arts Res. J., July-Sep 2012, 1(3): 31-38. 35. Table 3: Fertility intentions of men and women living with HIV/AIDS on ART in Nekemte town, East. Wollega, Ethiopia, February 2010. Characteristics. Men (%). Women (%). Number of alive children n=296 n=296. No living ...
Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M.
Compared to the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells they interact and fuse with two dimorphic female gametes (egg and central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca2+ is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes including mammals. PMID:26859271
Full Text Available One of the main problems of nursery plant production is the proper use of substrates and fertilization routines to achieve morphological and physiological plant quality, to resist and overcome environmental conditions for country establishment. This study evaluated the effects of different levels of slow-release fertilizer on early growth of Cedrela odorata L., in container production. A completely randomized experimental design was used with a substrate composed by sawdust (70% and a peat moss-perlite-vermiculite mixture -60:20:20- respectively (30%, four levels of slow-release fertilizer Osmocote Plus™ (12/09/1915 0, 6, 9 and 12 Kg/m3, as factors. After three and half months plants with fourth fertilization level (12kg/m3 showed the highest values for shoot dry weight, root dry weight, total dry weight, shoot / root ratio, and quality indexes (slenderness and Dickson. Fertilization level 3 (9 Kg/m3 fertilizer had the highest values for height and diameter. According to results there is a direct relationship between fertilization rate and studied variables, as fertilizer rate increases these will increase too. However, the application of 12 kg/m3 caused a slight phytotoxicity effect leading to decline plant height and diameter, compared with treatment of 9 kg/m3. According this and no statistical significance difference of these two treatments data, 9 kg/m3 treatment is technically the best one in technical and economic sense, because of it implies savings of 3 kg fertilizer per cubic meter in substrate, than of 12 kg/m3 treatment with almost the same results.
Zhang, Weidong; Zhao, Yong; Zhang, Pengfei; Hao, Yanan; Yu, Shuai; Min, Lingjiang; Li, Lan; Ma, Dongxue; Chen, Liang; Yi, Bao; Tang, Xiangfang; Meng, Qingshi; Liu, Lei; Wang, Shukun; Shen, Wei; Zhang, Hongfu
Numerous epidemiological studies suggest that air pollutants cause a decline in the quality of human spermatozoa and thus a reduction in fertility. However, the exact cause of infertility remains unknown. Air pollution gases, such as NH3 and H2S are either free or bound to airborne particular materials (PM) and are abundant and reactive. The aim of this current investigation was to explore the impacts of NH3 and/or H2S on male fertility and the underlying mechanisms. Male mouse exposed to H2S and/or NH3 and after two generations were used to evaluate the impacts on fertility. The fertility, and spermatozoa quality parameters and proteins involved in spermatogenesis were investigated. Our current investigation demonstrates: i) H2S and/or NH3 decrease male fertility by 20-30%, reduce the spermatozoa concentration about 20-40%, decrease 10-20%, increase around 30%; ii) the reduction in male fertility by H2S and/or NH3 can be inheritable; iii) H2S and/or NH3 can diminish male fertility through the disruption of spermatogenesis without affecting other body parameters such as body weight and organ index. One component of air pollutants, for example NH3, does not have a severe impact; however, two or more pollutants such as H2S and NH3 combined can cause serious health problems, especially with regard to male fertility. We suggest that greater attention should be paid to these air pollutants to improve human health and fertility. Copyright © 2017 Elsevier Ltd. All rights reserved.