Global Phosphorus Fertilizer Market and National Policies: A Case Study Revisiting the 2008 Price Peak

PubMed Central

Khabarov, Nikolay; Obersteiner, Michael

2017-01-01

The commodity market super-cycle and food price crisis have been associated with rampant food insecurity and the Arab spring. A multitude of factors were identified as culprits for excessive volatility on the commodity markets. However, as it regards fertilizers, a clear attribution of market drivers explaining the emergence of extreme price events is still missing. In this paper, we provide a quantitative assessment of the price spike of the global phosphorus fertilizer market in 2008 focusing on diammonium phosphate (DAP). We find that fertilizer market policies in India, the largest global importer of phosphorus fertilizers and phosphate rock, turned out to be a major contributor to the global price spike. India doubled its import of P-fertilizer in 2008 at a time when prices doubled. The analysis of a wide set of factors pertinent to the 2008 price spike in phosphorus fertilizer market leads us to the discovery of a price spike magnification and triggering mechanisms. We find that the price spike was magnified on the one hand by protective trade measures of fertilizer suppliers leading to a 19% drop in global phosphate fertilizer export. On the other hand, the Indian fertilizer subsidy scheme led to farmers not adjusting their demand for fertilizer. The triggering mechanism appeared to be the Indian production outage of P-fertilizer resulting in the additional import demand for DAP in size of about 20% of annual global supply. The main conclusion is that these three factors have jointly caused the spike, underscoring the need for ex ante improvements in fertilizer market regulation on both national and international levels. PMID:28660192

Eucalyptus development in degraded soil fertilized with sewage sludge and mineral fertilizer

NASA Astrophysics Data System (ADS)

Rodrigues, R. A. F.; Santos, E. B.; Alves, M. C.; Arruda, O. G.

2012-04-01

The aim of this study was to compare the development of eucalyptus in a degraded Oxisol with mineral fertilizer and sewage sludge. The study was conducted in Selviria, Mato Grosso do Sul, Brasil. The culture of eucalyptus was planted in 2003 at 2.0 m x 1.5 m spacing, with application of 60 Mg ha-1 of sewage sludge (dry basis) and mineral fertilizer. After five years (2008) the area received biosolids and mineral fertilizer, and after five months, were evaluated for height and diameter at breast height of Eucalyptus. The experimental design was randomized blocks with four treatments: T1 - control (without addition of inputs), T2 - Mineral fertilization (30 kg ha-1 N, 90 kg ha-1 of P2O5 and 60 kg ha-1 K2O), T3 - Reapplication of 4.64 Mg ha-1 of sewage sludge, dry basis, T4 - Reapplication of 9.28 Mg ha-1 of sewage sludge, dry basis. Before reapplication the biosolids plant height was higher in the eucalyptus with treatment 9.28 Mg ha-1 of sewage sludge (8.03 m) compared to control (5.75 m) and mineral fertilizer (5.91 m) and that treatment 4.64 Mg ha-1 of sewage sludge (6.34 m) did not differ from the previous three. For the diameter at breast height was the highest value for treatment with 9.28 Mg ha-1 (7.78 cm) compared to control (5.23 cm) and 4.64 Mg ha-1 (5.03 cm), and that of mineral fertilizer (5.96 cm) did not differ from all treatments. After reapplication of sludge plant height was higher in the eucalyptus treatment with 9.28 Mg ha-1 of sewage sludge (11.21 m) compared with control (7.51 m), mineral fertilizer (7.77 m) and 4 64 Mg ha-1 (8.07 m), which did not differ. The diameter at breast height had the same behavior before the application of biosolids in the highest value observed being 9.28 Mg ha-1 (8.46 cm) compared with control (5.75 cm) and 4.64 Mg ha-1 (5.03 cm) and that of mineral fertilizer (6.34 cm) did not differ from the others. Reapplication of the dose of 9.28 Mg ha-1 of sewage sludge in degraded Oxisol provided greater height and diameter at

Forecasting the effects of fertility control on overabundant ungulates: White-tailed deer in the National Capital Region

USGS Publications Warehouse

Raiho, Ann M.; Hooten, Mevin B.; Bates, Scott; Hobbs, N. Thompson

2015-01-01

Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, fertility control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that fertility control is incapable of rapidly reducing deer abundance. Fertility control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.

Forecasting the Effects of Fertility Control on Overabundant Ungulates: White-Tailed Deer in the National Capital Region.

PubMed

Raiho, Ann M; Hooten, Mevin B; Bates, Scott; Hobbs, N Thompson

2015-01-01

Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, fertility control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that fertility control is incapable of rapidly reducing deer abundance. Fertility control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.

Religiosity and Fertility in the United States: The Role of Fertility Intentions

ERIC Educational Resources Information Center

Hayford, Sarah R.; Morgan, S. Philip

2008-01-01

Using data from the 2002 National Survey of Family Growth, we show that women who report that religion is "very important" in their everyday life have both higher fertility and higher intended fertility than those saying religion is "somewhat important" or "not important." Factors such as unwanted fertility, age at…

Fertility desires and fertility outcomes.

PubMed

Bracher, M; Santow, G

1991-05-01

An Australian 1-in-1000 national probability sample conducted in 1986 yielded 2547 women aged 20-59 who provided detailed life histories on marital unions, childbearing, and contraception. Age specific fertility rates, desired family size, differentials in desired family size, desired fertility and achieved fertility, and sequential family building are examined. The results indicate that the desired family size at 1st marriage has declined only slightly over the past 30 years. 3 children are generally desired, and ver few desire 2. The constance of fertility desires in contrasted with the fertilitydecline to below replacement levels. Several reasons are suggested for the desired family size: the desire is for a family size within the family tradition and modified by the desire to have 1 of each sex, the desire reflects less on intentions but more on normative pressure to become a parent. Marrying is self selecting on the desire for a traditional family of at least 2 children. There is a rising age at marriage as well as a decline in marriages. Desired family size exceeds completed fertility. Period factors and personal circumstances affect fertility intentions. Future inquires should explore the multiple factors relating to fertility, rather than in comparing fertility desires and actual fertility. The data collected on age specific fertility were comparable to official estimates. The fertility decline was evidenced in all groups except teenagers. The decline was nearly 50% for those 20-24 years between the 1050's-80's, 33% for ages 25-29. Marriage patterns explain this decline in part. Between 1971-76, women aged 20-25 were married 37 months out of 60 months in 1971-76 versus 25 out of 60 months in 1981-86. Within the 25 year age group, marital fertility has declined and unmarried fertility, which is low, has risen, Women in a marital union of any kind has remained stable. Fertility within de facto unions, which is lower than within marriage, is higher than

Fertility behavior in developing economies: an investment approach.

PubMed

Chernichovsky, D

1982-01-01

By studying intergenerational benefits from children, this paper shows that the economic analysis of fertility behavior in developing economics can provide a systematic discussion of this behavior. The major hypotheses set forth are: 1) the effect of income on fertility depends on the source and timing of income; 2) in a lifetime context, parents, or would-be parents, who have higher incomes at young ages compared with the income they anticipate at old age, are expected to have a higher demand for children; and 3) the reverse of the latter is predicted for parents who anticipate relatively higher incomes at old age. These hypotheses follow the idea that, in the absence of other appropriate means for intertemporal transfers of wealth, parents even out the lifetime welfare through fertility behavior. Under these circumstances, fertility rates are expected to increase in communities where children abandon their traditional commitments to their aging parents, as may happen during periods of economic and cultural transition. A decline in mortality rates will induce lower fertility. This model suggests that a tax-financed social security scheme along with family planning will be conducive to a reduction in fertility. A test on data from an Indian village in 1968-69 suggests that in a traditional setting there is a correlation between household welfare, measured by income or assets, and the presence of grown children. Income has a positive effect on fertility when the parents' incomes comes from labor rather than human and nonhuman capital which provides income at later stages of life. Longitudinal data depicting income, savings, and fertility patterns over time should prove more promising in exploring the issues discussed.

Has Thailand's fertility decline stalled?

PubMed

Knodel, J; Chayovan, N; Frisen, C

1988-09-01

Thailand is 1 of the third world countries in which a very substantial fertility decline has occurred during the last 2 decades. However, there has been some recent concern, based on fertility rates derived from 3 national contraceptive prevalence surveys conducted in 1978/1979, 1981, and 1984, that the fertility decline may have lost momentum at a level well above replacement fertility. New evidence now available from a more recent national survey which permits calculation of retrospective fertility trends, in combination with those from registration data, clearly contradicts the suggestion of a fall in the fertility decline. Moreover, because expected family size remains low among women currently starting their reproductive careers and evidence shows that the preferred number of children has fallen more or less steadily, low fertility may be expected to be a feature of the Thai population for some time to come.

Globalization and Contemporary Fertility Convergence.

PubMed

Hendi, Arun S

2017-09-01

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.

Commercial fertilizers 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hargett, N.L.; Berry, J.T.; Montgomery, M.H.

1991-12-01

This document contains consumption data for commercial fertilizers in the USA for 1991. Graphical information on the consumption by class is given for the nation. State by state data for consumption of several types of commercial fertilizers are presented. Only numerical data is included.

Fertility knowledge and intentions to have children in a national study of Australian secondary school students.

PubMed

Heywood, Wendy; Pitts, Marian K; Patrick, Kent; Mitchell, Anne

2016-10-01

This paper reports on fertility knowledge and intentions to have children among a national sample of students in years 10-12. Data were from the Fifth National Survey of Australian Secondary Students and Sexual Health. Students identified factors that could affect fertility, if they wanted children and at what age. Most students wanted to have children (77%). Of those who wanted children or were unsure (n=1,780), 54% were able to identify six of eight factors that could affect fertility. Male students had poorer knowledge than females. Poorer knowledge was also reported by male students who were born overseas or used marijuana and by female students who were sexually active or religious. More than half the students (59%) wanted their first child aged 25-29, while 19% wanted their first child after 30. Intentions to have children at an earlier age were associated with being religious, sexually active (females), and using marijuana (males). Students not exclusively attracted to the opposite sex were more likely to want children at an older age. Most students typically want children in their late 20s. Many were unaware of factors that could affect their fertility and there was a mismatch between intentions and likely behaviour. These factors could be addressed as part of relationship education. © 2016 Public Health Association of Australia.

Marriage and fertility in the developed countries.

PubMed

Westoff, C F

1978-12-01

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

Fertility, immigration, and the fight against climate change.

PubMed

Earl, Jake; Hickey, Colin; Rieder, Travis N

2017-10-01

Several philosophers have recently argued that policies aimed at reducing human fertility are a practical and morally justifiable way to mitigate the risk of dangerous climate change. There is a powerful objection to such "population engineering" proposals: even if drastic fertility reductions are needed to prevent dangerous climate change, implementing those reductions would wreak havoc on the global economy, which would seriously undermine international antipoverty efforts. In this article, we articulate this economic objection to population engineering and show how it fails. We argue, first, that the economic objection paints an inaccurate picture of the complicated relationship between demographic change and economic growth, and second, that any untoward economic effects of fertility reduction can be mitigated with additional policies. Specifically, we argue that supplementing fertility reduction with policies that facilitate the emigration of younger people from developing nations to developed nations could allow for both global reductions in GHG emissions and continued economic stability. Further, we show that moral arguments against such unprecedented increases in immigration are unsuccessful. We conclude that population engineering is a practical and morally justifiable tool for addressing the twin evils of climate change and global poverty. © 2017 John Wiley & Sons Ltd.

Female Labor Supply and Fertility in Iran: A Comparison Between Developed, Semi Developed and Less Developed Regions.

PubMed

Emamgholipour Sefiddashti, Sara; Homaie Rad, Enayatollah; Arab, Mohamad; Bordbar, Shima

2016-02-01

Female labor supply has been changed dramatically in the recent yr. In this study, we examined the effects of development on the relationship between fertility and female labor supply. We used data of population and housing census of Iran and estimated three separate models. To do this we employed Logistic Regressions (BLR). The estimation results of our study showed that there was a negative relationship between fertility rate and female labor supply and there are some differences for this relationship in three models. When fertility rate increases, FLS would decreases. In addition, for higher fertility rates, the woman might be forced to work more because of the economic conditions of her family; and negative coefficients of the fertility rate effects on FLS would increase with a diminishing rate.

Low Fertility at the Turn of the Twenty-First Century

PubMed Central

Morgan, S. Philip; Taylor, Miles G.

2010-01-01

In the past few decades, demographic concerns have shifted from rapid population growth fueled by high fertility to concerns of population decline produced by very low, sub-replacement fertility levels. Once considered a problem unique to Europe or developed nations, concerns now center on the global spread of low fertility. Nearly half of the world's population now lives in countries with fertility at or below replacement levels. Further, by the mid-twenty-first century three of four countries now described as developing are projected to reach or slip below replacement fertility. We review the research on low fertility through the predominant frameworks and theories used to explain it. These explanations range from decomposition and proximate determinant frameworks to grand theories on the fundamental causes underlying the pervasiveness and spread of low fertility. We focus on the ability of theory to situate previous and future findings and conclude with directions for furthur research. PMID:20376287

Effects of radiocobalt irradiation of unfertilized or fertilized rabbit OVA in vitro on subsequent fertilization and development in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, M C; Hunt, D M; Romanoff, E B

Freshly shed rabbit ova recovered from the Fallopian tubes were irradiated with a radiocobalt source at 45 r to 32,000 r and then transplanted into the left tube of mated rabbits. The ova were recovered and examined microscopically 10 hours to 24 hours, two days and 6 days after transplantation for the determination of fertilization, cleavage, and blastocyst formation. The fetus and uterine contents were examined macroscopically 22 to 25 days after transplantation. The proportion of fertilized ova decreased from 71% at a very low dosage, 45 r, to 46% at a very high dosage, 32,000 r. The proportion ofmore » normally cleaved ova and normal lilastocysts decreased from about 95% at 45 r, to about 3% at 500 r, to 0% at 6,500 r. The proportion of embryonic development decreased from 49% at 45 r, to 21% at 90 r, to 0% at 800 r. A chromosomal bridge was observed in an ovum irradiated at 6,500 r. Failure of second polar body division in one out of 23 ova irradiated at 6,500 r and polyspermy in one out of 32 ova irradiated at 32,000 r before fertilization was observed. When fertilized rabbit ova at the two cell stage were irradiated at 45 r to 6,500 r and examined at various times after transplantation, it was found that the proportion of normal cleavage decreased from 78% at 45 r to 33% at 800 r, to 0% at 6,500 r. The proportion of normal blastocysts decreased from 61% at 45 r, to 20% at 800 r, to 0% at 6,500 r. The proportion of normal embryonic development decreased from 46% at 45 r, to 12% at 500 r, to 0% at 6,500 r. In combination with data from a previous study of the irraiation of rabbit sper matozoa in vitro the following points are revealed: No abnormal fetus, no high proportion of degeneration after implantation, and no disturbance of the sex ratio were observed whether spermatozoa, or ova, unfertilized, or fertilized, were irradiated from 45 r to 800 r. Although there may be a differential sensitivity to various dosages for the subsequent cleavage and blastocyst

Fertility and the family.

PubMed

Kono, S

1991-09-01

The developed countries of Asia include Japan and the newly industrialized economies of Hong Kong, Taiwan, Republic of Korea, and Singapore. These 5 societies share various similarities that have helped in their socioeconomic development. The 1st includes a significant and quite rapid socioeconomic development (per capita gross national product, urbanization, demographic transition, educational attainment, and industrialization). The 2nd similarity is the extremely high levels of education. Indeed those 5 societies boast the most highly educated populations in Asia. 3rd, they have achieved below replacement fertility. In fact, they never really had very high birth rates anyhow. 4th, extended families are the norm despite rapid transformation of their societies. Confucianism, the 5th similarity, advocates multigenerational families. Children understand that it is their duty to always take care of their parents. Parents know that they have a right to ask for their children's help at any time. In 1981, a demographer hypothesized that 1 of the leading signs of fertility decline is the nucleation of the family. yet in these 5 societies nucleation did not appear before fertility decline. In fact, in Japan, fertility is higher in those homes where the grandmother watches her grandchildren while the daughter or daughter-in-law is at work. Some have compared the role of Confucianism in socioeconomic development with that of Protestantism in the industrialization of Europe. Both stress hard work, simplicity, frugality, discipline, and regularity in daily life. Yet Confucianism sees women as bearers of children and servants to men. Women in these societies protest this mindset by postponing marriage and having few children. If these societies wish to increase fertility, they need to restructure their male oriented societies.

In vitro and in vivo effects of ulipristal acetate on fertilization and early embryo development in mice.

PubMed

Gómez-Elías, Matías D; Munuce, María J; Bahamondes, Luis; Cuasnicú, Patricia S; Cohen, Débora J

2016-01-01

vitro embryo culture. Considering the ethical and technical limitations inherent to the use of human gametes for fertilization studies, the mouse model was used as an approach for exploring the potential effects of UPA on in vivo sperm transport and fertilization. Nevertheless, the extrapolation of these results to humans requires further investigation. This study presents new evidence on the lack of effect of UPA on gamete interaction and embryo development, providing new insights into the mechanism of action of UPA as an emergency contraceptive method with potential clinical implications. These new findings could contribute to increase the acceptability and proper use of UPA as an emergency contraceptive method. This study was partially supported by a National Agency of Scientific and Technological Promotion (ANPCyT), Argentina grants PICT 2011-061 to D.J.C. and PICT 2011-2023 to P.S.C. None of the authors has any competing interests to declare. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Adolescent fertility management: the Sierra Leone experience.

PubMed

Lamin, M M; Singleton, A

1982-01-01

Because of growing concerns for the problems of adolescent fertility, a training program in Adolescent Fertility Management was conducted in Sierra Leone in 1981. The program was designed to actuate the interdisciplinary energies necessary for exploring the depth of the problem and to develop strategies for possible solutions. 2 program activities were conducted: a Former Participant Conference, which resulted in the development of a draft of a country-wide program; and a 2-week training workshop. In order to create public awareness, the participants presented an original drama, a synopsis of which is provided. Solutions to the problems of adolescent fertility must address not only the availability and use of contraceptives, but also a reorientation of the attitudes of parents on sex education. The practice of expelling pregnant adolescents from educational institutions only serves to compound the problems. A list of the topics covered during the workshops is provided, as are a summary of the conclusions and subsequent recommendations. Participants voted to form a national organization whose main objective is the reduction of teenage pregnancy by at least 12% within a 12 month period through the creation of a national awareness campaign.

Development of Malaysian women fertility index: Evidence from Shannon's entropy

NASA Astrophysics Data System (ADS)

Jalil, Wan Aznie Fatihah Wan Abd; Sharif, Shamshuritawati

2017-11-01

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.

Calcium at fertilization and in early development

PubMed Central

Whitaker, Michael

2012-01-01

Fertilization calcium waves are introduced and the evidence from which we can infer general mechanisms of these waves is presented. The two main classes of hypothesis put forward to explain the generation of the fertilization calcium wave are set out and it is concluded that initiation of the fertilization calcium wave can be most generally explained in inverterbrates by a mechanism in which an activating substance enters the egg from the sperm on sperm-egg fusion, activating the egg by stimulating phospholipase C activation through a src family kinase pathway and in mammals by the diffusion of a sperm-specific phospholipase C from sperm to egg on sperm-egg fusion. The fertilization calcium wave is then set into the context of cell cycle control and the mechanism of repetitive calcium spiking in mammalian eggs is investigated. Evidence that calcium signals control cell division in early embryos is reviewed, and it is concluded that calcium signals are essential at all three stages of cell division in early embryos. Evidence that phosphoinositide signalling pathways control the resumption of meiosis during oocyte maturation is considered. It is concluded on balance that the evidence points to a need for phosphoinositide/calcium signalling during resumption of meiosis. Changes to the calcium signalling machinery occur during meiosis to enable the production of a calcium wave in the mature oocyte when it is fertilized; evidence that the shape and structure of the endoplasmic reticulum alters dynamically during maturation and after fertilization is reviewed and the link between ER dynamics and the cytoskeleton is discussed. There is evidence that calcium signalling plays a key part in the development of patterning in early embryos. Morphogenesis in ascidian, frog and zebrafish embryos is briefly described to provide the developmental context in which calcium signals act. Intracellular calcium waves that may play a role in axis formation in ascidian are discussed

[Fertility in rural and urban areas of Mexico].

PubMed

Garcia Y Garma, I O

1989-01-01

Data from 6 fertility surveys conducted in Mexico between 1969-87 were used to compare rural and urban fertility and to determine whether a significant level of contraceptive usage could be achieved in rural areas despite their lack of socioeconomic development. Age-specific marital fertility rates were calculated for the 4 national-level and 2 rural fertility surveys. The index of fertility control developed by Coale and Trussel was calculated for rural, urban, and all areas. The marital total fertility rate in rural areas declined from 10.6 in 1970 to 7.4 in 1982, a decline of 2.5% annually. From 1982-87 the annual rate of decline in rural fertility slowed to 1.6%, reaching 6.8 children in 1987. The urban marital total fertility rate declined from 7.72 in 1976 to 5.03 in 1987, while the marital total fertility rate for Mexico as a whole declined from 9.04 in 1976 to 5.85 in 1987. The indices of fertility control showed slowly increasing use of contraception in rural areas starting from the very low level of 1969. The urban index of fertility control showed some contraceptive use for all age groups in all surveys. The increases in contraceptive usage were considerable in rural areas from 1976-82 and much less marked in urban areas. From 1982-87 the inverse was observed and the fertility decline in urban areas was more marked. The condition of natural fertility found in rural areas in 1969 subsequently disappeared. Over time, fertility decline and use of contraception have intensified. Contraception is widely practiced in urban areas and is continuing to become more prevalent. The rural fertility decline in 1976-82 suggests that at least sometimes increases in fertility control are more important in rural areas than in urban areas. The theory of modernization, which holds that fertility decline in developed countries is attributable to factors associated with the process of modernization, thus comes into question. However, it is probable that a sustained fertility

South Korea's low fertility raises European-style issues.

PubMed

Haub, C

1991-10-01

A demographic revolution has taken place in South Korea as evidenced by the marked decline in total fertility rate (TFR) from 6 in 1960 to the 1987 level of 1.6. South Korea holds the record for low fertility among developing countries, with women in South Korea averaging fewer children in their lifetimes than do women in Europe. The 1987 TFR for South Korea was even less than that of Sweden, Norway, and France. Emphasizing high initial rates of contraceptive use, family planning (FP) has been a strong component of South Korea's 5-year plans since 1962. Strong governmental support backed the efforts of a large group of FP workers who provided free contraceptives from private physicians. High discontinuation rates resulted, however, and the abortion rate has soared to equal the number of live births. Albeit a developing nation, South Korea now faces the challenges of below replacement fertility more typical of more developed countries. Current fertility levels indicate population increase to approximately 50 million by 2020, followed by a slow decline. While reducing pressure on limited resources, population decline and demographic aging will also demand allocation of a higher proportion of government funds to medical care, and potentially threaten South Korea's competitiveness in the world labor market. Having effected decreases in population growth and fertility, the government reduced the annual sterilization target in 1986 from 300,000 to 60,000 by 1991, and will increasingly turn to the private sector and national health insurance for service provision to all but the poor. A 2-child family norm may be promoted, FP programs expanded to the unmarried and legislation developed to eliminate the preference for sons. Delivery systems may also be reorganized to encourage continued use of contraceptive methods.

Containment of fertilizers and pesticides at retail operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broder, M.F.

1990-06-28

Environmental protection has become as important to the fertilizer retailer as the products and services he offers. Emphasis on environmental protection at the dealer level is largely in response to state regulations designed to protect groundwater. The national Clean Water Act of 1987 gave states the lead in developing groundwater protection strategies. Several states have adopted new or stronger regulations and others are moving to do so. Fertilizer dealers need to keep up with these regulations and promote groundwater protection. This paper describes several containment systems for fertilizers and pesticides to help dealers decide how to modify their plants tomore » protect groundwater.« less

Fertilizer consumption trend in developing countries vs. developed countries.

PubMed

Motesharezadeh, Babak; Etesami, Hassan; Bagheri-Novair, Sepideh; Amirmokri, Hormoz

2017-03-01

The study of the chemical fertilizer consumption in different countries provides basal data for the decision-making of fertilizer production and for the environmental impact assessment of fertilizer application. Hence, the aim of this research was to study and compare the trend of the chemical fertilizer consumption from 1980 to 2012 in Iran, Turkey, Japan, Germany, France, and the USA. For this purpose, various indices such as application rates (kg ha -1 ) of N, P, and K, arable land, and total fertilizer consumption were analysed. Results showed that the application rates of nutrients (N-P 2 O 5 -K 2 O) in Iran, Turkey, Japan, Germany, France, and the USA in 2012 were 100-42-7, 100-42-7, 100-94-60, 100-17-25, 100-13-38, and 100-33-35, respectively. The lowest and highest area under production were observed in Japan with 4.0 million ha (0.033 ha/person) and in the USA with 155.0 million ha (0.51 ha/person) during 2008-2015, respectively. In addition, the highest and lowest application rates of net nutrient consumption were recorded in France and Germany (285 and 285 kg ha -1 ) and in Iran (66 kg ha -1 ), respectively. Overall, the average net consumption of fertilizers in the studied countries in three recent decades (million tonnes) decreased in the order: the USA (19.282) > France (4.601) > Germany (3.302) > Turkey (1.825) > Japan (1.604) > Iran (1.130). Regarding an estimated 9.2 billion people by 2050, the balanced consumption of nutrients (N-P 2 O 5 -K 2 O) and the principles of optimal consumption of fertilizers are keys for achieving the increased food production, food security, and environmental conservation.

Aspects of psychosocial development in infertile versus fertile men.

PubMed

Akhondi, Mohammad Mehdi; Binaafar, Sima; Ardakani, Zohreh Behjati; Kamali, Kourosh; Kosari, Haleh; Ghorbani, Behzad

2013-04-01

Infertility is one of the most difficult life experiences that a couple might encounter. Infertility as a bio-psycho-social phenomenon, could influence all aspects of life. While paying special attention to the psychological aspects of infertility in couples; many studies have investigated the non-clinical aspects of infertility, however, they rarely have evaluated the psychosocial development of infertile versus fertile men. We aimed to study the effects of infertility on psychosocial development in men. In fact, we designed the study based on "Erikson's theory of psychosocial development". We focused on the relationship between psychosocial development and some self-conceived indices. For this purpose, we divided the participants volunteers into two groups of cases (80 infertile men) and controls (40 fertile men) and asked them to complete a 112 (questions questionnaire based on "self description"). The statistical analysis was performed by SPSS (version 13) using independent t-test, Pearson correlation coefficient and analysis of covariance. A p-value <0.05 was considered significant. Data analysis showed significant inter and intra group differences. Infertile and fertile groups showed significant differences in trust, autonomy, generativity and integrity stages (p < 0.05). Infertile intergroup analysis represents us to higher scores in positive than negative stages. Infertility as a phenomenon had its own effects on the psychosocial development of infertile men. However, good coping skills are powerful tools to manage these myriad of feelings surrounding infertile men.

DEVELOPMENT OF AN ELECTROSPRAY MASS SPECTROMETRIC METHOD FOR DETERMINING PERCHLORATE IN FERTILIZERS

EPA Science Inventory

An electrospray mass spectrometric method has been developed for application to agricultural and horticultural fertilizers to determine perchlorate. After fertilizers are leached or dissolved in water, the method relies on the formation of stable ion pair complex of the perchlor...

How to influence fertility: the experience so far.

PubMed

Weeks, J R

1990-09-01

Even though fertility in the US is 2, the population grows each year by 2.5 million people due to natural increase and immigration. The US has never had a formal population policy to influence its birth rate. Yet the US government advises other nations, especially developing nations, how they should go about reducing their fertility. Instead the US can learn from population policies of direct disincentives, such as no income tax allowance for 3 children. In Indonesia, the president and Islamic religious leaders strongly support family planning. In Mexico, both the public and private sectors provide family planning services. The US does not have experience in influencing fertility declines, since fertility declined due to economic development over a period of time. Some scholars claim that there are 3 preconditions for a sustained decline in fertility, all of which have significance for setting population policies. The 1st is called rational choice in which conditions are such in a society that women can make their own decision. For example, the existence of legislation that guarantees women the right to act in their own interest, including the right to make their own reproductive decisions. The 2nd involves policies or conditions that motivate individuals and/or couples to limit family size. Incentives and disincentives can provide the needed motivation. For example, the government pays a woman for not having a child for a specific interval. The last precondition includes the necessity of having means available to limit family size. These means include knowledge of contraceptive methods and accessibility to them.

Determinants of fertility in Rwanda in the context of a fertility transition: a secondary analysis of the 2010 Demographic and Health Survey.

PubMed

Ndahindwa, Vedaste; Kamanzi, Collins; Semakula, Muhammed; Abalikumwe, François; Hedt-Gauthier, Bethany; Thomson, Dana R

2014-12-13

Major improvements to Rwanda's health system, infrastructure, and social programs over the last decade have led to a rapid fertility transition unique from other African countries. The total fertility rate fell from 6.1 in 2005 to 4.6 in 2010, with a 3-fold increase in contraceptive usage. Despite this rapid national decline, many women still have large numbers of children. This study investigates predictors of fertility during this fertility transition to inform policies that improve individuals' reproductive health and guide national development. We used Poisson regression to separately model number of children born to ever married/cohabitated women (n = 8,309) and never married women (n = 1,220) age 15 to 49 based on 2010 Rwanda Demographic and Health Survey data. We used backward stepwise regression with a time offset to identify individual and household factors associated with woman's fertility level, accounting for sampling weights, clustering, and stratification. In ever married/cohabitating women, high fertility was significantly associated (p < 0.05) with the following variables: unmet need for contraception (IRR = 1.07), women's desire for children (5+ versus 0-2 children: IRR = 1.22), woman's number of siblings (8-20 versus 0-4: IRR = 1.03), and couples who desired different numbers of children (husband wants more: IRR = 1.04; husband wants fewer: IRR = 1.04). Low fertility in ever married/cohabitating women was associated with women's education (higher versus no education: IRR = 0.66), household wealth (highest versus lowest quintile: IRR = 0.93), and delayed sexual debut (25+ versus 8-18 years: IRR = 0.49). In never married women, low fertility was associated with education (higher versus no education: IRR = 0.22), household wealth (highest versus lowest quintile: IRR = 0.58), delayed sexual debut (25-49 versus 8-18 years: IRR = 0.43), and having an unmet need for contraception (IRR = 0.69). Although the study design does not allow causal conclusions

Microgravity Effecs During Fertilization, Cell Division, Development, and Calcium Metabolism in Sea Urchins

NASA Technical Reports Server (NTRS)

Schatten, Heide

1999-01-01

Calcium loss and muscle atrophy are two of the main metabolic changes experienced by astronauts and crew members during exposure to microgravity in space. For long-term exposure to space it is crucial to understand the underlying mechanisms for altered physiological functions. Fundamental occurrences in cell biology which are likely to depend on gravity include cytoskeletal dynamics, chromatin and centrosome cycling, and ion immobilization. These events can be studied during fertilization and embryogenesis within invertebrate systems. We have chosen the sea urchin system to study the effects of microgravity on cytoskeletal processes and calcium metabolism during fertilization, cell division, development, and embryogenesis. Experiments during an aircraft parabolic flight (KC-135) demonstrated: (1) the viability of sea urchin eggs prior to fertilization, (2) the suitability of our specimen containment system, (3) the feasibility of fertilization in a reduced gravity environment (which was achieved during 25 seconds of reduced gravity under parabolic flight conditions). Two newly developed pieces of spaceflight hardware made further investigations possible on a spaceflight (STS-77); (1) the Aquatic Research Facility (ARF), and (2) the Fertilization Syringe Unit (FSU). The Canadian Space Agency developed ARF to conduct aquatic spaceflight experiments requiring controlled conditions of temperature, humidity, illumination, and fixation at predetermined time points. It contained a control centrifuge which simulated the 1 g environment of earth during spaceflight. The FSU was developed at the Kennedy Space Center (KSC) by the Bionetics Corporation specifically to enable the crew to perform sea urchin fertilization operations in space.

Simulated Microgravity Influences Bovine Oocyte In Vitro Fertilization and Preimplantation Embryo Development

USDA-ARS?s Scientific Manuscript database

The aim of this study was to investigate whether in vitro fertilization and preimplantation embryos exposed to a simulated microgravity environment in vitro would improve, or be deleterious to, their fertilization and embryonic development. A Rotating Cell Culture System™ (RCCS) bioreactor with a Hi...

Aspects of Psychosocial Development in Infertile Versus Fertile Men

PubMed Central

Akhondi, Mohammad Mehdi; Binaafar, Sima; Ardakani, Zohreh Behjati; Kamali, Kourosh; Kosari, Haleh; Ghorbani, Behzad

2013-01-01

Background Infertility is one of the most difficult life experiences that a couple might encounter. Infertility as a bio-psycho-social phenomenon, could influence all aspects of life. While paying special attention to the psychological aspects of infertility in couples; many studies have investigated the non-clinical aspects of infertility, however, they rarely have evaluated the psychosocial development of infertile versus fertile men. We aimed to study the effects of infertility on psychosocial development in men. Methods In fact, we designed the study based on “Erikson's theory of psychosocial development”. We focused on the relationship between psychosocial development and some self-conceived indices. For this purpose, we divided the participants volunteers into two groups of cases (80 infertile men) and controls (40 fertile men) and asked them to complete a 112 (questions questionnaire based on “self description”). The statistical analysis was performed by SPSS (version 13) using independent t-test, Pearson correlation coefficient and analysis of covariance. A p-value <0.05 was considered significant. Results Data analysis showed significant inter and intra group differences. Infertile and fertile groups showed significant differences in trust, autonomy, generativity and integrity stages (p < 0.05). Infertile intergroup analysis represents us to higher scores in positive than negative stages. Conclusion Infertility as a phenomenon had its own effects on the psychosocial development of infertile men. However, good coping skills are powerful tools to manage these myriad of feelings surrounding infertile men. PMID:23926571

Development policy and the projects for fertility decline in Bangladesh.

PubMed

Cain, M; Lieberman, S S

1983-09-01

This paper reviews Bangladesh's government policy and suggests which development measures other than family planning services would increase contraceptive usage. It develops a framework for policy analysis by reviewing the fertility determinants literature in general, and that on Bangladesh. Conventional approaches, based on demographic transition theory (which presupposes economic development in the Third World will follow the historical path of the West, with attendant rates of urbanization and industrialization) and the microeconomic theory of consumer choice (whereby costs of children are measured only in the context of the internal workings of the household without regard to outside influences) are rejected in favor of an institutional framework, which emphasizes the productive value of children in the context of the institutional underpinnings of the costs and benefits of children. The analysis identifies the extremely harsh environment of risk, and the absence of effective forms of risk insurance, as crucial to understanding the persistence of Bangladesh's high fertility. It concludes that to ensure the country's fertility transition, the positive reproductive incentive associated with children as insurance against risk must be eliminated or reduced. Therefore policies with the greatest impact on reproductive behavior would either alter the environment of risk or introduce other effective means of adjusting to risk. Among the components of the development program in the Second Five Year Plan, rural public employment measures hold the greatest promise for reducing fertility. Such current initiatives have had program limitations, such as relief rather than long-term orientation and bottlenecks in communication and transportation. However, these efforts form a basis for developing a policy of guaranteed public works employment. This policy's potential flexibility, broad base, and success in other parts of South Asia (particularly Maharashtra State, India) make

Kerala reaps low fertility dividends.

PubMed

1992-01-01

Unlike much of India, the state of Kerala has promoted the development of human resources, resulting in lower fertility rates. If current UN projections are correct, India will overtake China as the most populous nation in the world by 2025. Within India, however, great differences exist in fertility rates, reflecting the level of commitment from state governments. In India, state governments control much of the policy and spending on health, education, etc. While the state of Kerala has been among the most committed to human resource development in the developing world, India's 5 northern states (Rajasthan, Uttar Pradesh, Madhya Pradesh, Bihar, and Orissa) have been among the least committed. As a result, Kerala's fertility rate has fallen to 2.3 children/women--a rate lower than that of Thailand, China, the formers USSR, or Ireland. Kerala has a contraceptive prevalence rate 3 times the national average and the lowest infant mortality rate in all of India--only 26/1000 live births (infant mortality is 4-5 times higher in the 5 northern states). Only 27% of Kerala's population lives in poverty, compared to 34-49.5% in the northern states. Real incomes and industrialization have been growing faster in Kerala. And industrialization does not appear to have come at the expense of the environment. 2 factors are responsible for Kerala' accomplishments: 1) State government support of human development--the state has invested in health, education, and has conducted a land reform benefiting 3 million landless peasants. 2) The status of women--in Kerala, women are viewed as an asset, not a liability (as in the north). Kerala's female literacy is 66%, compared to 11-21% in the northern states. Kerala also enjoys the highest level of female labor force participation (35%) anywhere in India.

Nonmarital Fertility and the Effects of Divorce Rates on Youth Suicide Rates

ERIC Educational Resources Information Center

Messner, Steven F.; Bjarnason, Thoroddur; Raffalovich, Lawrence E.; Robinson, Bryan K.

2006-01-01

Using pooled, time-series data for a sample of 15 developed nations, we assess the effect of divorce rates on gender-specific suicide rates for youths aged 15-19 with models of relative cohort size, lagged nonmarital fertility, and an interaction term for divorce rates and nonmarital fertility. The results reveal that, for young men, relative…

Development Context, Regional Differences among Young Women, and Fertility: The Ecuadorian Amazon.

ERIC Educational Resources Information Center

Lobao, Linda M.; Brown, Lawrence A.

1998-01-01

Data from the 1990 Ecuadorian census indicate that expected fertility-reducing effects of women's education, student status, and labor force participation were lessened in the Amazon as a consequence of its family-based economy, class structure, and high-fertility demographic regime. Development of the extractive periphery in Ecuador is…

Prevalence of Child Marriage and its Impact on the Fertility and Fertility Control Behaviors of Young Women in India

PubMed Central

Raj, Anita; Saggurti, Niranjan; Balaiah, Donta; Silverman, Jay G.

2009-01-01

Objectives Child marriage in India is considered a major barrier to the nation's social and economic development, as well as a major women's health concern. The current study assesses prevalence of child marriage (i.e., marriage prior to the national legal age of 18 years) among young adult women in India, and associations between child marriage and women's fertility and fertility control behaviors. Study Design Cross-sectional analyses of a nationally representative household sample of Indian women ages 16-49 years (N=124,385) collected in 2005-2006 via the National Family Health Survey-3. Participants Analyses were restricted to women age 20-24 years (n=22,807) and the subsample of ever married women aged 20-24 years (n=14,628). Data Analysis Prevalence estimates of child marriage were produced for all women 20-24 years. Using the ever married subsample, simple regression models, models adjusted for demographics, and models adjusted for demographics and duration of marriage were constructed to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between child marriage and both fertility and fertility control outcomes. Fertility and Fertility Control Outcomes No contraception prior to childbirth, childbirth within first year of marriage, high fertility (3 or more births), history of recent rapid repeat childbirth, unwanted pregnancy, and female sterilization. Results Child marriage was reported by 44.5% of Indian women ages 20-24 years; 22.6% reported marriage prior to age 16 years, and 2.6% were married prior to age 13 years. Child marriage was significantly associated with women's increased risk for no contraceptive use prior to first childbirth (AOR=1.37, 95% CI=1.22, 1.54), high fertility (AOR=7.40, 95% CI=6.45, 8.50), history of rapid repeat childbirth (AOR=3.00, 95% CI=2.74, 3.29), multiple unwanted pregnancies (AOR=2.36, 95% CI=1.90, 2.94), pregnancy termination (AOR=1.22; 95% CI=1.06, 1.41) and female sterilization (AOR=5

Fertility treatment: long-term growth and mental development of the children.

PubMed

Bay, Bjørn

2014-10-01

Fertility treatment has been associated with obstetrical and perinatal complications. It is, however, uncertain whether fertility treatment or parental subfertility is associated with long-term development of the children. We aimed to assess the growth and mental health of children and adolescents conceived after fertility treatment compared to spontaneously conceived controls. First, we evaluated all previous studies comparing neurodevelopmental outcomes between children conceived after fertility treatment and spontaneous conceived controls. The systematic review clarified methodological limitations in the existing literature on the long-term development of children conceived after medical assisted reproduction. Although several studies had been published, large, well-controlled studies with long-term follow-up and thorough statistical adjustments were still few. Second, we evaluated the children's mental health by assessing the risk of mental disorders. We studied a population of 555,828 children conceived after spontaneous conception and 33,139 children conceived after fertility treatment with follow-up in 2012 when the children were 8-17 years old. The absolute risk and hazard ratio of overall and specific mental disorders were estimated while adjusting for potential confounding variables. Further, we estimated the association between subtypes of procedures, hormonal treatment, gamete types and cause of infertility on the one hand and the risk of mental disorders on the other. Children conceived after ovulation induction had a low, but significantly increased risks of autism spectrum disorders, hyperkinetic disorders, conduct, emotional, or social disorders, and tic disorders. Children conceived after IVF or ICSI showed no increased risk, except for a small risk of tic disorders. There was no risk systematically related to any specific type of hormone drug treatment. Thus, the increased risks may rely on residual confounding such as unknown parental factors

Application of intracytoplasmic sperm injection (ICSI) for fertilization and development in birds.

PubMed

Shimada, Kiyoshi; Ono, Tamao; Mizushima, Shusei

2014-01-15

Intracytoplasmic sperm injection (ICSI) technology in birds has been hampered due to opacity of oocyte. We developed ICSI-assisted fertilization and gene transfer in quail. This paper reviews recent advances of our ICSI experiments. The oocyte retrieved from the oviduct and a quail sperm was injected into the oocyte under a stereomicroscope. The oocyte was cultured for 24h at 41°C under 5% CO2 in air. The fertilization and development was assessed by microscopic observation. The fertility rate ranged 12-18% and development varied from stage II to V in trials. To improve the fertility rate, phospholipase C (PLC) zeta was injected with a sperm. It was increased to 37-50%. Furthermore, injection of inositol trisphosphate increased to over 85%. Quail oocyte can be fertilized with chicken sperm and so can testicular elongated spermatid. To extend embryonic development, chicken eggshell was used as a surrogate culture at 37°C after the 24h incubation at 41°C under 5% CO2 in air. It survived up to 2days thereafter. Finally, gene transfer was attempted in quail egg. The sperm membrane was disrupted with Triton X-100 (TX-100) and was injected with PLCzeta cRNA and enhanced green fluorescent protein (EGFP) gene in oocyte. The GFP expression was evaluated at 24h incubation at 41°C under 5% CO2 in air in the embryos. While the expression was not detected in the control oocytes, the experimental treatment induced blastoderm development (44%) of the oocytes and 86% of blastoderm showed fluorescent emission. In addition, PCR analysis detected EGFP fragments in 50% of GFP-expressing blastoderm. Our ICSI method may be the first step toward the production of transgenic birds. Copyright © 2013 Elsevier Inc. All rights reserved.

Reproductive Management for Optimal Oocyte Development to Enhance Fertility

USDA-ARS?s Scientific Manuscript database

There are multiple steps associated with the ovulatory follicle that affect oocyte growth, fertilization, embryo development and establishment of pregnancy. When estrous cycles are manipulated with assisted reproductive technologies and ovulation induced, some of these variables become more importa...

Nutrition advocacy and national development: the PROFILES programme and its application.

PubMed

Burkhalter, B R; Abel, E; Aguayo, V; Diene, S M; Parlato, M B; Ross, J S

1999-01-01

Investment in nutritional programmes can contribute to economic growth and is cost-effective in improving child survival and development. In order to communicate this to decision-makers, the PROFILES nutrition advocacy and policy development programme was applied in certain developing countries. Effective advocacy is necessary to generate financial and political support for scaling up from small pilot projects and maintaining successful national programmes. The programme uses scientific knowledge to estimate development indicators such as mortality, morbidity, fertility, school performance and labour productivity from the size and nutritional condition of populations. Changes in nutritional condition are estimated from the costs, coverage and effectiveness of proposed programmes. In Bangladesh this approach helped to gain approval and funding for a major nutrition programme. PROFILES helped to promote the nutrition component of an early childhood development programme in the Philippines, and to make nutrition a top priority in Ghana's new national child survival strategy. The application of PROFILES in these and other countries has been supported by the United States Agency for International Development, the United Nations Children's Fund, the World Bank, the Asian Development Bank, the Micronutrient Initiative and other bodies.

Nutrition advocacy and national development: the PROFILES programme and its application.

PubMed Central

Burkhalter, B. R.; Abel, E.; Aguayo, V.; Diene, S. M.; Parlato, M. B.; Ross, J. S.

1999-01-01

Investment in nutritional programmes can contribute to economic growth and is cost-effective in improving child survival and development. In order to communicate this to decision-makers, the PROFILES nutrition advocacy and policy development programme was applied in certain developing countries. Effective advocacy is necessary to generate financial and political support for scaling up from small pilot projects and maintaining successful national programmes. The programme uses scientific knowledge to estimate development indicators such as mortality, morbidity, fertility, school performance and labour productivity from the size and nutritional condition of populations. Changes in nutritional condition are estimated from the costs, coverage and effectiveness of proposed programmes. In Bangladesh this approach helped to gain approval and funding for a major nutrition programme. PROFILES helped to promote the nutrition component of an early childhood development programme in the Philippines, and to make nutrition a top priority in Ghana's new national child survival strategy. The application of PROFILES in these and other countries has been supported by the United States Agency for International Development, the United Nations Children's Fund, the World Bank, the Asian Development Bank, the Micronutrient Initiative and other bodies. PMID:10361758

Development and agronomical validation of new fertilizer compositions of high bioavailability and reduced potential nutrient losses.

PubMed

Erro, Javier; Urrutia, Oscar; San Francisco, Sara; Garcia-Mina, Jose M

2007-09-19

To optimize the economical cost of each unit of fertilizer applied and to reduce the environmental contamination caused by nutrient losses, the development of highly efficient granulated fertilizers is of great importance. This study proposes a strategy that consists of developing specific fertilizers having nutrient release patterns that are dependent on plant activity in the rhizosphere. This type of fertilizer is named "rhizosphere-controlled fertilizer" (RCF fertilizer). This fertilizer is based on the introduction of an organomineral matrix composed of metal [Mg (Ca is also possible), Zn (Fe and other metals are also possible)]-humic phosphates. The presence of this matrix modifies the nutrient release pattern of the fertilizer. In this way there are two main nutrient fractions: (i) a water-soluble fraction or "starter" fraction and (ii) a "rhizosphere-controlled" fraction insoluble in water but soluble by the action of the rhizospheric acids released by plants and microorganisms. This study shows the chemical and structural characterization of the organomineral matrix, as well as its efficiency in slowing the nutrient release rate of the RCF fertilizer, principally with respect to P and N. It is demonstrated how these properties of the matrix were also reflected in the significant reduction in both ammonia volatilization and N leaching in a pot system consisting of wheat plants cultivated in a calcareous soil and fertilized with a RCF fertilizer.

Sustaining food self-sufficiency of a nation: The case of Sri Lankan rice production and related water and fertilizer demands.

PubMed

Davis, Kyle Frankel; Gephart, Jessica A; Gunda, Thushara

2016-04-01

Rising human demand and climatic variability have created greater uncertainty regarding global food trade and its effects on the food security of nations. To reduce reliance on imported food, many countries have focused on increasing their domestic food production in recent years. With clear goals for the complete self-sufficiency of rice production, Sri Lanka provides an ideal case study for examining the projected growth in domestic rice supply, how this compares to future national demand, and what the associated impacts from water and fertilizer demands may be. Using national rice statistics and estimates of intensification, this study finds that improvements in rice production can feed 25.3 million Sri Lankans (compared to a projected population of 23.8 million people) by 2050. However, to achieve this growth, consumptive water use and nitrogen fertilizer application may need to increase by as much as 69 and 23 %, respectively. This assessment demonstrates that targets for maintaining self-sufficiency should better incorporate avenues for improving resource use efficiency.

The relationship between poverty and fertility in some less developed countries.

PubMed

Chin Ptc

1985-12-01

The author investigates the extent to which both absolute and relative poverty affect population growth in developing countries. Aggregate data from U.N. sources for 26 countries at various stages of the fertility transition are used. The results indicate that the most significant steps in reducing fertility would be more effective provision of basic human needs and reforms in land tenure. The need to distinguish between absolute and relative poverty in formulating population policies is noted.

Amphibian fertilization and development in microgravity

NASA Technical Reports Server (NTRS)

Souza, K. A.; Black, S. D.

1985-01-01

An experiment investigating the effects of gravity on embryonic development in amphibians is proposed. The planned procedures for the preparation of the frog eggs for launching in the Space Shuttle, for the injection of the eggs with gonadotropin, for the insertion of the eggs into egg chambers, for the storage of one of the chambers in a microgravity area and the second into a centrifuge, and for the fertilization of the eggs are described. The later organogenesis, swimming behavior, cytoplasmic components, cellular formation, neural plate and archenteron expansion, and allometry and expansion of the organ systems will be examined. Normal morphology for embryos and tadpoles developing at microgravity and the formation of the neural plate opposite the sperm entry point meridian are predicted.

The Determinants of Low Fertility in India

PubMed Central

Dharmalingam, A.; Rajan, Sowmya; Morgan, S. Philip

2015-01-01

Using a conceptual framework focusing on factors that enhance or reduce fertility relative to desired family size (see Bongaarts 2001), we study fertility variation across time (1992–2006) and space (states) in India. Our empirical analyses use data from three waves of the Indian National Family Health Surveys. We find that this framework can account for a substantial portion of the variation in the TFR across the states and over time. Our estimates focus attention on the critical components of contemporary Indian fertility, especially desired family size, unwanted fertility, son preference, and fertility postponement. PMID:24993746

Transcriptomic Analysis Reveals Mechanisms of Sterile and Fertile Flower Differentiation and Development in Viburnum macrocephalum f. keteleeri

PubMed Central

Lu, Zhaogeng; Xu, Jing; Li, Weixing; Zhang, Li; Cui, Jiawen; He, Qingsong; Wang, Li; Jin, Biao

2017-01-01

Sterile and fertile flowers are an important evolutionary developmental (evo-devo) phenotype in angiosperm flowers, playing important roles in pollinator attraction and sexual reproductive success. However, the gene regulatory mechanisms underlying fertile and sterile flower differentiation and development remain largely unknown. Viburnum macrocephalum f. keteleeri, which possesses fertile and sterile flowers in a single inflorescence, is a useful candidate species for investigating the regulatory networks in differentiation and development. We developed a de novo-assembled flower reference transcriptome. Using RNA sequencing (RNA-seq), we compared the expression patterns of fertile and sterile flowers isolated from the same inflorescence over its rapid developmental stages. The flower reference transcriptome consisted of 105,683 non-redundant transcripts, of which 5,675 transcripts showed significant differential expression between fertile and sterile flowers. Combined with morphological and cytological changes between fertile and sterile flowers, we identified expression changes of many genes potentially involved in reproductive processes, phytohormone signaling, and cell proliferation and expansion using RNA-seq and qRT-PCR. In particular, many transcription factors (TFs), including MADS-box family members and ABCDE-class genes, were identified, and expression changes in TFs involved in multiple functions were analyzed and highlighted to determine their roles in regulating fertile and sterile flower differentiation and development. Our large-scale transcriptional analysis of fertile and sterile flowers revealed the dynamics of transcriptional networks and potentially key components in regulating differentiation and development of fertile and sterile flowers in Viburnum macrocephalum f. keteleeri. Our data provide a useful resource for Viburnum transcriptional research and offer insights into gene regulation of differentiation of diverse evo-devo processes in

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

PubMed

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

2016-09-01

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

Evolution of China's family planning policy and fertility transition.

PubMed

Lin, F

1998-06-01

This article points out the important role of family planning (FP) in controlling population growth in China. The impact of development on fertility decline is much slower. China's current FP policy promotes deferred marriage and deferred childbearing and fewer, but healthier, births. The policy promotes one child per couple. Rural couples in certain circumstances, such as if the first birth is a girl, are allowed to have a second child that is properly spaced. FP should be promoted in ethnic inhabited areas. Under this policy, fertility declined from 2.59 to 2 children/woman during the period 1987-92. In more developed areas, fertility has declined below replacement level to 1.6. FP was first promoted in the National Program for Agricultural Development in the 1950s. Birth control was promoted in densely populated areas without high minority concentrations. Fertility hovered around 6.1 during 1950-57. The Cultural Revolution halted fertility decline. The 1974 FP policy emphasized deferred marriage and deferred childbearing, and spaced (by 4-5 years) but fewer births. Fertility declined from 4.2 to 2.3 during 1974-80, in response to the government directive. Rural population declined from 4.6 to 2.5, and urban population declined from 2.0 to 1.15. The one-child policy was promoted in 1980 and became official state policy. FP became an obligation to the state. Rural areas were less compliant with the one-child policy, which led to the 1984 allowances for a second child.

The development of a phosphite-mediated fertilization and weed control system for rice.

PubMed

Manna, Mrinalini; Achary, V Mohan M; Islam, Tahmina; Agrawal, Pawan K; Reddy, Malireddy K

2016-04-25

Fertilizers and herbicides are two vital components of modern agriculture. The imminent danger of phosphate reserve depletion and multiple herbicide tolerance casts doubt on agricultural sustainability in the future. Phosphite, a reduced form of phosphorus, has been proposed as an alternative fertilizer and herbicide that would address the above problems to a considerable extent. To assess the suitability of a phosphite-based fertilization and weed control system for rice, we engineered rice plants with a codon-optimized ptxD gene from Pseudomonas stutzeri. Ectopic expression of this gene led to improved root growth, physiology and overall phenotype in addition to normal yield in transgenic plants in the presence of phosphite. Phosphite functioned as a translocative, non-selective, pre- and post-emergent herbicide. Phosphite use as a dual fertilizer and herbicide may mitigate the overuse of phosphorus fertilizers and reduce eutrophication and the development of herbicide resistance, which in turn will improve the sustainability of agriculture.

The development of a phosphite-mediated fertilization and weed control system for rice

PubMed Central

Manna, Mrinalini; Achary, V. Mohan M.; Islam, Tahmina; Agrawal, Pawan K.; Reddy, Malireddy K.

2016-01-01

Fertilizers and herbicides are two vital components of modern agriculture. The imminent danger of phosphate reserve depletion and multiple herbicide tolerance casts doubt on agricultural sustainability in the future. Phosphite, a reduced form of phosphorus, has been proposed as an alternative fertilizer and herbicide that would address the above problems to a considerable extent. To assess the suitability of a phosphite-based fertilization and weed control system for rice, we engineered rice plants with a codon-optimized ptxD gene from Pseudomonas stutzeri. Ectopic expression of this gene led to improved root growth, physiology and overall phenotype in addition to normal yield in transgenic plants in the presence of phosphite. Phosphite functioned as a translocative, non-selective, pre- and post-emergent herbicide. Phosphite use as a dual fertilizer and herbicide may mitigate the overuse of phosphorus fertilizers and reduce eutrophication and the development of herbicide resistance, which in turn will improve the sustainability of agriculture. PMID:27109389

County-level estimates of nitrogen and phosphorus from commercial fertilizer for the Conterminous United States, 1987–2006

USGS Publications Warehouse

Gronberg, Jo Ann M.; Spahr, Norman E.

2012-01-01

The U.S. Geological Survey’s National Water-Quality Assessment program requires nutrient input for analysis of the national and regional assessment of water quality. Detailed information on nutrient inputs to the environment are needed to understand and address the many serious problems that arise from excess nutrients in the streams and groundwater of the Nation. This report updates estimated county-level farm and nonfarm nitrogen and phosphorus input from commercial fertilizer sales for the conterminous United States for 1987 through 2006. Estimates were calculated from the Association of American Plant Food Control Officials fertilizer sales data, Census of Agriculture fertilizer expenditures, and U.S. Census Bureau county population. A previous national approach for deriving farm and nonfarm fertilizer nutrient estimates was evaluated, and a revised method for selecting representative states to calculate national farm and nonfarm proportions was developed. A national approach was used to estimate farm and nonfarm fertilizer inputs because not all states distinguish between farm and nonfarm use, and the quality of fertilizer reporting varies from year to year. For states that distinguish between farm and nonfarm use, the spatial distribution of the ratios of nonfarm-to-total fertilizer estimates for nitrogen and phosphorus calculated using the national-based farm and nonfarm proportions were similar to the spatial distribution of the ratios generated using state-based farm and nonfarm proportions. In addition, the relative highs and lows in the temporal distribution of farm and nonfarm nitrogen and phosphorus input at the state level were maintained—the periods of high and low usage coincide between national- and state-based values. With a few exceptions, nonfarm nitrogen estimates were found to be reasonable when compared to the amounts that would result if the lawn application rates recommended by state and university agricultural agencies were used. Also

How economic development and family planning programs combined to reduce Indonesian fertility.

PubMed

Gertler, P J; Molyneaux, J W

1994-02-01

This paper examines the contributions of family planning programs, economic development, and women's status to Indonesian fertility decline from 1982 to 1987. Methodologically we unify seemingly conflicting demographic and economic frameworks into a single "structural" proximate-cause model as well as controlling statistically for the targeted (nonrandom) placement of family planning program inputs. The results are consistent with both frameworks: 75% of the fertility decline resulted from increased contraceptive use, but was induced primarily through economic development and improved education and economic opportunities for females. Even so, the dramatic impact of the changes in demand-side factors (education and economic development) on contraceptive use was possible only because there already existed a highly responsive contraceptive supply delivery system.

Embryonic development in human oocytes fertilized by split insemination

PubMed Central

Kim, Myo Sun; Kim, Jayeon; Youm, Hye Won; Park, Jung Yeon; Choi, Hwa Young

2015-01-01

Objective To compare the laboratory outcomes of intracytoplasmic sperm injection (ICSI) and conventional insemination using sibling oocytes in poor prognosis IVF cycles where ICSI is not indicated. Methods Couples undergoing IVF with following conditions were enrolled: history of more than 3 years of unexplained infertility, history of ≥3 failed intrauterine insemination, leukocytospermia or wide variation in semen analysis, poor oocyte quality, or ≥50% of embryos had poor quality in previous IVF cycle(s). Couples with severe male factor requiring ICSI were excluded. Oocytes were randomly assigned to the conventional insemination (conventional group) or ICSI (ICSI group). Fertilization rate (FR), total fertilization failure, and embryonic development at day 3 and day 5 were assessed. Results A total of 309 mature oocytes from 37 IVF cycles (32 couples) were obtained: 161 were assigned to conventional group and 148 to ICSI group. FR was significantly higher in the ICSI group compared to the conventional group (90.5% vs. 72.7%, P<0.001). Total fertilization failure occurred in only one cycle in conventional group. On day 3, the percentage of cleavage stage embryos was higher in ICSI group however the difference was marginally significant (P=0.055). In 11 cycles in which day 5 culture was attempted, the percentage of blastocyst (per cleaved embryo) was significantly higher in the ICSI group than the conventional group (55.9% vs. 25.9%, P=0.029). Conclusion Higher FR and more blastocyst could be achieved by ICSI in specific circumstances. Fertilization method can be tailored accordingly to improve IVF outcomes. PMID:26023671

Development and certification of the new SRM 695 trace elements in multi-nutrient fertilizer

USGS Publications Warehouse

MacKey, E.A.; Cronise, M.P.; Fales, C.N.; Greenberg, R.R.; Leigh, S.D.; Long, S.E.; Marlow, A.F.; Murphy, K.E.; Oflaz, R.; Sieber, J.R.; Rearick, M.S.; Wood, L.J.; Yu, L.L.; Wilson, S.A.; Briggs, P.H.; Brown, Z.A.; Budahn, J.; Kane, P.F.; Hall, W.L.

2007-01-01

During the past seven years, several states within the US have enacted regulations that limit the amounts of selected non-nutritive elements in fertilizers. Internationally, several countries, including Japan, China, and Australia, and the European Union also limit the amount of selected elements in fertilizers. The elements of interest include As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, and Zn. Fertilizer manufacturers and state regulatory authorities, faced with meeting and verifying these limits, need to develop analytical methods for determination of the elements of concern and to validate results obtained using these methods. Until now, there were no certified reference materials available with certified mass fraction values for all elements of interest in a blended, multi-nutrient fertilizer matrix. A new standard reference material (SRM) 695 trace elements in multi-nutrient fertilizer, has been developed to help meet these needs. SRM 695 has recently been issued with certified mass fraction values for seventeen elements, reference values for an additional five elements, and information values for two elements. The certificate of analysis includes an addendum listing percentage recovery for eight of these elements, determined using an acid-extraction inductively-coupled plasma optical-emission spectrometry (ICP-OES) method recently developed and tested by members of the Association of American Plant Food Control Officials. ?? Springer-Verlag 2007.

When Do Laws Matter? National Minimum-Age-of-Marriage Laws, Child Rights, and Adolescent Fertility, 1989–2007

PubMed Central

Kim, Minzee; Longhofer, Wesley; Boyle, Elizabeth Heger; Nyseth, Hollie

2014-01-01

Using the case of adolescent fertility, we ask the questions of whether and when national laws have an effect on outcomes above and beyond the effects of international law and global organizing. To answer these questions, we utilize a fixed-effect time-series regression model to analyze the impact of minimum-age-of-marriage laws in 115 poor- and middle-income countries from 1989 to 2007. We find that countries with strict laws setting the minimum age of marriage at 18 experienced the most dramatic decline in rates of adolescent fertility. Trends in countries that set this age at 18 but allowed exceptions (for example, marriage with parental consent) were indistinguishable from countries that had no such minimum-age-of-marriage law. Thus, policies that adhere strictly to global norms are more likely to elicit desired outcomes. The article concludes with a discussion of what national law means in a diffuse global system where multiple actors and institutions make the independent effect of law difficult to identify. PMID:25525281

Future fertility for individuals with differences of sex development: Parent attitudes and perspectives about decision-making.

PubMed

Johnson, Emilie K; Rosoklija, Ilina; Shurba, Angela; D'Oro, Anthony; Gordon, Elisa J; Chen, Diane; Finlayson, Courtney; Holl, Jane L

2017-08-01

Children, adolescents, and young adults (children/youth) with differences/disorders of sex development (DSD) face challenges related to future fertility; this may be due to variations in gonadal development, and, for some, gonadectomy performed to reduce the risk of malignancy. Childhood may be the only time for preservation of biological fertility potential for children/youth who undergo gonadectomy or have early gonadal failure. Fertility-related decision-making for these patients is particularly complicated, due to the need for parental proxy decision-making, potential discordance between gender identity and gonadal type, and uncertain future assisted reproductive technologies. This study aimed to assess: (1) attitudes regarding future fertility, and (2) healthcare needs for fertility-related decision-making among parents of children/youth with DSD. Semi-structured qualitative interviews about future fertility were conducted with parents of children/youth with DSD. Parents who had never discussed fertility with a healthcare provider were excluded. Grounded theory methodology was used to identify emergent themes and patterns. Demographics and clinical characteristics were assessed via survey and medical chart review. Nineteen parents were interviewed (participation rate: 60%, 14 mothers/5 fathers, median patient age at diagnosis 6 months (range 0-192), eight DSD diagnoses). The most common emergent themes are summarized in the Summary Table. Most parents identified fertility as a key concern, both at time of diagnosis and throughout development. Parents expressed difficulty with timing of disclosure about potential infertility to their children. Multiple preferences related to medical decision-making about future fertility and fertility preservation were expressed, including: a desire for step-by-step decision-making, and use of medically vetted information and research to guide decisions. This qualitative study provided new information about the perspectives of

Prevalence of child marriage and its effect on fertility and fertility-control outcomes of young women in India: a cross-sectional, observational study.

PubMed

Raj, Anita; Saggurti, Niranjan; Balaiah, Donta; Silverman, Jay G

2009-05-30

Child marriage is a substantial barrier to social and economic development in India, and a primary concern for women's health. We assessed the prevalence of child marriage-ie, before 18 years of age-in young adult women in India, and the associations between child marriage and women's fertility and fertility-control outcomes. Data from the National Family Health Survey-3 (2005-06) were limited to a sample of Indian women aged 20-24 years (n=22 807), of whom 14 813 had been or were presently married (ever-married). Prevalence of child marriage was estimated for the whole sample. We used regression models adjusted for demographics, and models adjusted for demographics and duration of marriage to estimate odds ratios (ORs) for the associations between child marriage and both fertility and fertility-control outcomes, in the ever-married subsample. 44.5% of women aged 20-24 years were married before age 18 years, 22.6% were married before age 16 years, and 2.6% were married before age 13 years. Child marriage was significantly associated with no contraceptive use before first childbirth (adjusted OR 1.37 [95% CI 1.22-1.54]), high fertility (three or more births) (7.40 [6.45-8.50]), a repeat childbirth in less than 24 months (3.00 [2.74-3.29]), multiple unwanted pregnancies (2.36 [1.90-2.94]), pregnancy termination (1.48 [1.34-1.63]), and female sterilisation (6.68 [5.78-7.60]). The association between child marriage and high fertility, a repeat childbirth in less than 24 months, multiple unwanted pregnancies, pregnancy termination, and sterilisation all remained significant after controlling for duration of marriage. Increased enforcement of existing policies is crucial for prevention of child marriage. Improved family-planning education, access, and support are urgently needed for women married as children, their husbands, and their families to reduce the high fertility and poor fertility-control outcomes of this practice. US National Institutes of Health and Indian

Development and Evaluation of a Low Fertility Ontology for Analyzing Social Data in Korea.

PubMed

Lee, Ji-Hyun; Park, Hyeoun-Ae; Song, Tae-Min

2016-01-01

The purpose of this study is to develop a low fertility ontology for collecting and analyzing social data. A low fertility ontology was developed according to Ontology Development 101 and formally represented using Protégé. The content coverage of the ontology was evaluated using 1,387 narratives posted by the public and 63 narratives posted by public servants. Six super-classes of the ontology were developed based on Bronfenbrenner's ecological system theory with an individual in the center and environmental systems impacting their as surroundings. In total, 568 unique concepts were extracted from the narratives. Out of these concepts, 424(74.6%) concepts were lexically or semantically mapped, 67(11.8%) were either broadly or narrowly mapped to the ontology concepts. Remaining 77(13.6%) concepts were not mapped to any of the ontology concepts. This ontology can be used as a framework to understand low fertility problems using social data in Korea.

Controlling Fertility.

ERIC Educational Resources Information Center

Donnay, France

1991-01-01

Recent developments in fertility control are presented in relation to the global demographic situation. Discussion focuses on changes in scientific knowledge and concepts that have shifted the focus from birth control to planned parenthood to the notion of controlled fertility. The place of family planning programs, including their socioeconomic…

Liquid Organic Fertilizers for Sustainable Agriculture: Nutrient Uptake of Organic versus Mineral Fertilizers in Citrus Trees

PubMed Central

Martínez-Alcántara, Belén; Martínez-Cuenca, Mary-Rus; Bermejo, Almudena; Legaz, Francisco; Quiñones, Ana

2016-01-01

The main objective of this study was to compare the performance of two liquid organic fertilizers, an animal and a plant-based fertilizer, with mineral fertilization on citrus trees. The source of the fertilizer (mineral or organic) had significant effect in the nutritional status of the organic and conventionally managed mandarins. Nutrient uptake, vegetative growth, carbohydrate synthesis and soil characteristics were analyzed. Results showed that plants fertilized with animal based liquid fertilizers exhibited higher total biomass with a more profuse development of new developing organs (leaves and fibrous roots). Liquid organic fertilization resulted in an increased uptake of macro and micronutrients compared to mineral fertilized trees. Moreover, organic fertilization positively affected the carbohydrate content (fructose, glucose and sucrose) mainly in summer flush leaves. Liquid organic fertilization also resulted in an increase of soil organic matter content. Animal-based fertilizer, due to intrinsic composition, increased total tree biomass and carbohydrate leaves content, and led to lower soil nitrate concentration and higher P and Mg exchangeable in soil extract compared to vegetal-based fertilizer. Therefore, liquid organic fertilizers could be used as an alternative to traditional mineral fertilization in drip irrigated citrus trees. PMID:27764099

Liquid Organic Fertilizers for Sustainable Agriculture: Nutrient Uptake of Organic versus Mineral Fertilizers in Citrus Trees.

PubMed

Martínez-Alcántara, Belén; Martínez-Cuenca, Mary-Rus; Bermejo, Almudena; Legaz, Francisco; Quiñones, Ana

2016-01-01

The main objective of this study was to compare the performance of two liquid organic fertilizers, an animal and a plant-based fertilizer, with mineral fertilization on citrus trees. The source of the fertilizer (mineral or organic) had significant effect in the nutritional status of the organic and conventionally managed mandarins. Nutrient uptake, vegetative growth, carbohydrate synthesis and soil characteristics were analyzed. Results showed that plants fertilized with animal based liquid fertilizers exhibited higher total biomass with a more profuse development of new developing organs (leaves and fibrous roots). Liquid organic fertilization resulted in an increased uptake of macro and micronutrients compared to mineral fertilized trees. Moreover, organic fertilization positively affected the carbohydrate content (fructose, glucose and sucrose) mainly in summer flush leaves. Liquid organic fertilization also resulted in an increase of soil organic matter content. Animal-based fertilizer, due to intrinsic composition, increased total tree biomass and carbohydrate leaves content, and led to lower soil nitrate concentration and higher P and Mg exchangeable in soil extract compared to vegetal-based fertilizer. Therefore, liquid organic fertilizers could be used as an alternative to traditional mineral fertilization in drip irrigated citrus trees.

The World Fertility Survey: January 1976-December 1976. Annual Report.

ERIC Educational Resources Information Center

World Fertility Survey, London (England).

This annual report describes, through narrative and statistical tables, the progress made in 1976 by the World Fertility Survey (WFS), an international population research program. The function of the WFS is to assist a large number of interested countries, particularly the developing countries, in carrying out nationally representative,…

Effects of Simulated Mobile Phone Electromagnetic Radiation on Fertilization and Embryo Development.

PubMed

Chen, Hong; Qu, Zaiqing; Liu, Wenhui

2017-04-01

This study investigated the effects of 935-MHz electromagnetic radiation (ER) on fertilization and subsequent embryonic development in mice. Ovulating mice were irradiated at three ER intensities for 4 h/day (d) or 2 h/d for three consecutive days; the ova were then harvested for in vitro fertilization to observe the 6-h fertilization rate (6-FR), 72-h morula rate (72-MR), and 110-h blastula rate (110-BR). Compared with the control group, the 6-FR, 72-MR, and 110-BR were decreased in the low ER intensity group, but the differences were not significant; in the mid- and high-intensity ER groups, 72-MR and 110-BR in the 4 h/d and 2 h/d subgroups were decreased, showing significant differences compared with the control group. Moreover, the comparison between 4 h/d and 2 h/d subgroups showed significant differences. Mid- and high-intensity ER at 935 MHz can reduce the fertilization rate in mice, and reduce the blastulation rate, thus reducing the possibility of embryo implantation.

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".

PubMed

Erfani, Amir

2014-12-01

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.

Evaluation of fertilization-to-planting and fertilization-to-harvest intervals for safe use of noncomposted bovine manure in Wisconsin vegetable production.

PubMed

Ingham, Steven C; Fanslau, Melody A; Engel, Rebecca A; Breuer, Jeffry R; Breuer, Jane E; Wright, Thomas H; Reith-Rozelle, Judith K; Zhu, Jun

2005-06-01

Fresh bovine manure was mechanically incorporated into loamy sand and silty clay loam Wisconsin soils in April 2004. At varying fertilization-to-planting intervals, radish, lettuce, and carrot seeds were planted; crops were harvested 90, 100, 110 or 111, and 120 days after manure application. As an indicator of potential contamination with fecal pathogens, levels of Escherichia coli in the manure-fertilized soil and presence of E. coli on harvested vegetables were monitored. From initial levels of 4.0 to 4.2 log CFU/g, E. coli levels in both manure-fertilized soils decreased by 2.4 to 2.5 log CFU/g during the first 7 weeks. However, E. coli was consistently detected from enriched soil samples through week 17, perhaps as a result of contamination by birds and other wildlife. In the higher clay silty clay loam soil, the fertilization-to-planting interval affected the prevalence of E. coli on lettuce but not on radishes and carrots. Root crop contamination was consistent across different fertilization-to-harvest intervals in silty clay loam, including the National Organic Program minimum fertilization-to-harvest interval of 120 days. However, lettuce contamination in silty clay loam was significantly (P < 0.10) affected by fertilization-to-harvest interval. Increasing the fertilization-to-planting interval in the lower clay loamy sand soil decreased the prevalence of E. coli on root crops. The fertilization-to-harvest interval had no clear effect on vegetable contamination in loamy sand. Overall, these results do not provide grounds for reducing the National Organic Program minimum fertilization-to-harvest interval from the current 120-day standard.

Trust and Fertility Dynamics

PubMed Central

Billari, Francesco C.; Pessin, Léa

2016-01-01

We argue that the divergence in fertility trends in advanced societies is influenced by the interaction of long-standing differences in generalized trust with the increase in women’s educational attainment. Our argument builds on the idea that trust enhances individuals’ and couples’ willingness to outsource childcare to outside their extended family. This becomes critically important as women’s increased education enhances the demand for combining work and family life. We test our hypothesis using data from the World Values Survey and European Values Study on 36 industrialized countries between the years 1981 and 2009. Multilevel statistical analyses reveal that the interaction between national-level generalized trust and cohort-level women’s education is positively associated with completed fertility. As education among women expands, high levels of generalized trust moderate fertility decline. PMID:28003707

Biodemographic Modeling of the Links Between Fertility Motivation and Fertility Outcomes in the NLSY79

PubMed Central

MILLER, WARREN B.; BARD, DAVID E.; PASTA, DAVID J.; RODGERS, JOSEPH LEE

2010-01-01

In spite of long-held beliefs that traits related to reproductive success tend to become fixed by evolution with little or no genetic variation, there is now considerable evidence that the natural variation of fertility within populations is genetically influenced and that a portion of that influence is related to the motivational precursors to fertility. We conduct a two-stage analysis to examine these inferences in a time-ordered multivariate context. First, using data from the National Longitudinal Survey of Youth, 1979, and LISREL analysis, we develop a structural equation model in which five hypothesized motivational precursors to fertility, measured in 1979–1982, predict both a child-timing and a child-number outcome, measured in 2002. Second, having chosen two time-ordered sequences of six variables from the SEM to represent our phenotypic models, we use Mx to conduct both univariate and multivariate behavioral genetic analyses with the selected variables. Our results indicate that one or more genes acting within a gene network have additive effects that operate through child-number desires to affect both the timing of the next child born and the final number of children born, that one or more genes acting through a separate network may have additive effects operating through gender role attitudes to produce downstream effects on the two fertility outcomes, and that no genetic variance is associated with either child-timing intentions or educational intentions. PMID:20608103

Cohort fertility in Western Europe: comparing fertility trends in recent birth cohorts.

PubMed

Hopflinger, F

1984-01-01

fertility was a decline in 3rd and higher order births. Most countries showed a decline in higher order births, and in some countries the decline was marked. The proportion of 1-child families increased in many countries and was especially high in Germany. The fertility decline may be leveling off in some of the countries. Fertility will probably stablize at a low level in most of the countries. The decline in fertility is due not only to increased contraceptive use but to the growing trend toward secular individualism in European society. The similarities in the fertility declines in all the countries indicates that identical cross national causes are influencing fertility behavior. The 16 countries included iln the study were Austria, Belgium, Denmark, England and Wales, Finland, France, Germany, Greece, Ireland, Italy, Netherlands, Norway, Portugal, Spain, Sweden, and Switzerland.

Education Differences in Intended and Unintended Fertility

ERIC Educational Resources Information Center

Musick, Kelly; England, Paula; Edgington, Sarah; Kangas, Nicole

2009-01-01

Using a hazards framework and panel data from the National Longitudinal Survey of Youth (1979-2004), we analyze the fertility patterns of a recent cohort of white and black women in the United States. We examine how completed fertility varies by women's education, differentiating between intended and unintended births. We find that the education…

Understanding the effects of low salinity on fertilization success and early development in the sand dollar Echinarachnius parma.

PubMed

Allen, Jonathan D; Pechenik, Jan A

2010-04-01

Free-spawning marine invertebrates that live near shore or in estuaries may experience reduced fertilization success during low-salinity events. Although several studies have documented reproductive failure at reduced salinity in estuarine animals, few have looked at whether developmental failure is due to a failure of fertilization or to a failure of fertilized eggs to cleave. In this study, we examined the effects of salinities ranging from 18 to 32 psu on fertilization success and early development in the sand dollar Echinarachnius parma. In addition to decoupling the effects of low salinity on fertilization from its effects on early cleavage, we also assessed whether eggs or sperm were the weak link in accounting for reproductive failure. We found that both fertilization and cleavage failed at salinities below about 22 psu but that development could be partially rescued by returning zygotes to full-strength seawater. We also found that sperm remained active and capable of fertilizing eggs even after being exposed to low salinities for 30 min.. Taken together, these results suggest that reproductive failure at low salinities in E. parma is due more to an inability of the fertilized eggs to cleave than to an inability of sperm to fertilize eggs.

Influences of selected socioeconomic and demographic variables on fertility in Bangladesh.

PubMed

Islam, S M; Khan, H T

1995-06-01

"The data used in this study are from the 1989 Bangladesh Fertility Survey (1989 BFS), which was conducted...by the National Institute of Population Research and Training (NIPORT)....A two-stage probability sample design was used for the survey.... It has been found that female age at marriage has a significant direct negative influence on fertility. Thus, raising the age at marriage by implementing a minimum-age marriage law is likely to lower fertility on a national scale. Duration of breast-feeding is also found to have a significant direct negative effect on fertility....Fetal loss appears to have a significant direct positive effect on fertility...which means that mothers who have experienced fetal loss are found to have higher fertility.... Maternal mortality is also high in Bangladesh. Therefore, it is essential to provide primary health care, particularly maternal and child health care, for surviving children." excerpt

Chinese culture and fertility decline.

PubMed

Wu, C; Jia, S

1992-01-01

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

Garlic (Allium sativum L.) fertility: transcriptome and proteome analyses provide insight into flower and pollen development

PubMed Central

Shemesh-Mayer, Einat; Ben-Michael, Tomer; Rotem, Neta; Rabinowitch, Haim D.; Doron-Faigenboim, Adi; Kosmala, Arkadiusz; Perlikowski, Dawid; Sherman, Amir; Kamenetsky, Rina

2015-01-01

Commercial cultivars of garlic, a popular condiment, are sterile, making genetic studies and breeding of this plant challenging. However, recent fertility restoration has enabled advanced physiological and genetic research and hybridization in this important crop. Morphophysiological studies, combined with transcriptome and proteome analyses and quantitative PCR validation, enabled the identification of genes and specific processes involved in gametogenesis in fertile and male-sterile garlic genotypes. Both genotypes exhibit normal meiosis at early stages of anther development, but in the male-sterile plants, tapetal hypertrophy after microspore release leads to pollen degeneration. Transcriptome analysis and global gene-expression profiling showed that >16,000 genes are differentially expressed in the fertile vs. male-sterile developing flowers. Proteome analysis and quantitative comparison of 2D-gel protein maps revealed 36 significantly different protein spots, 9 of which were present only in the male-sterile genotype. Bioinformatic and quantitative PCR validation of 10 candidate genes exhibited significant expression differences between male-sterile and fertile flowers. A comparison of morphophysiological and molecular traits of fertile and male-sterile garlic flowers suggests that respiratory restrictions and/or non-regulated programmed cell death of the tapetum can lead to energy deficiency and consequent pollen abortion. Potential molecular markers for male fertility and sterility in garlic are proposed. PMID:25972879

Sildenafil citrate (Viagra) impairs fertilization and early embryo development in mice.

PubMed

Glenn, David R J; McClure, Neil; Cosby, S Louise; Stevenson, Michael; Lewis, Sheena E M

2009-03-01

To determine the effects of sildenafil citrate, a cyclic monophosphate-specific type 5 phosphodiesterase inhibitor known to affect sperm function, on fertilization and early embryo cleavage. This acute mammal study included male and female mice assigned randomly, the females sacrificed after mating and their oocytes/embryos evaluated at four time periods after treatment. Academic research environment. Male and female CBAB(6) mice. Female mice were injected intraperitoneally with 5 IU gonadotropin (hCG) to stimulate follicular growth and induce ovulation. They were each caged with a male that had been gavaged with sildenafil citrate (0.06 mg/0.05 mL) and allowed to mate. After 12, 36, 60, and 84 h, females were killed, their oviducts were dissected out, and retrieved embryos were assessed for blastomere number and quality. Fertilization rates and numbers of embryos were evaluated after treatment. Fertilization rates (day 1) were markedly reduced (-33%) in matings where the male had taken sildenafil citrate. Over days 2-4, the numbers of embryos developing in the treated group were significantly fewer than in the control group. There was also a trend for impaired cleavage rates within those embryos, although this did not reach significance. The impairments to fertility caused by sildenafil citrate have important implications for infertility centers and for couples who are using this drug precoitally while attempting to conceive.

The life-history trade-off between fertility and child survival

PubMed Central

Lawson, David W.; Alvergne, Alexandra; Gibson, Mhairi A.

2012-01-01

Evolutionary models of human reproduction argue that variation in fertility can be understood as the local optimization of a life-history trade-off between offspring quantity and ‘quality’. Child survival is a fundamental dimension of quality in these models as early-life mortality represents a crucial selective bottleneck in human evolution. This perspective is well-rehearsed, but current literature presents mixed evidence for a trade-off between fertility and child survival, and little empirical ground to evaluate how socioecological and individual characteristics influence the benefits of fertility limitation. By compiling demographic survey data, we demonstrate robust negative relationships between fertility and child survival across 27 sub-Saharan African countries. Our analyses suggest this relationship is primarily accounted for by offspring competition for parental investment, rather than by reverse causal mechanisms. We also find that the trade-off increases in relative magnitude as national mortality declines and maternal somatic (height) and extrasomatic (education) capital increase. This supports the idea that socioeconomic development, and associated reductions in extrinsic child mortality, favour reduced fertility by increasing the relative returns to parental investment. Observed fertility, however, falls considerably short of predicted optima for maximizing total offspring survivorship, strongly suggesting that additional unmeasured costs of reproduction ultimately constrain the evolution of human family size. PMID:23034700

The fertility quality of life (FertiQoL) tool: development and general psychometric properties†

PubMed Central

Boivin, Jacky; Takefman, Janet; Braverman, Andrea

2011-01-01

BACKGROUND To develop the first international instrument to measure fertility quality of life (FertiQoL) in men and women experiencing fertility problems, to evaluate the preliminary psychometric properties of this new tool and to translate FertiQoL into multiple languages. METHOD We conducted a survey, both online and in fertility clinics in USA, Australia/New Zealand, Canada and UK. A total of 1414 people with fertility problems participated. The main outcome measure was the FertiQoL tool. RESULTS FertiQoL consists of 36 items that assess core (24 items) and treatment-related quality of life (QoL) (10 items) and overall life and physical health (2 items). Cronbach reliability statistics for the Core and Treatment FertiQoL (and subscales) were satisfactory and in the range of 0.72 and 0.92. Sensitivity analyses showed that FertiQoL detected expected relations between QoL and gender, parity and support-seeking. FertiQoL was translated into 20 languages by the same translation team with each translation verified by local bilingual fertility experts. CONCLUSIONS FertiQoL is a reliable measure of the impact of fertility problems and its treatment on QoL. Future research should establish its use in cross-cultural research and clinical work. PMID:21665875

Urinary bisphenol A concentrations and association with in vitro fertilization outcomes among women from a fertility clinic.

PubMed

Mínguez-Alarcón, Lidia; Gaskins, Audrey J; Chiu, Yu-Han; Williams, Paige L; Ehrlich, Shelley; Chavarro, Jorge E; Petrozza, John C; Ford, Jennifer B; Calafat, Antonia M; Hauser, Russ

2015-09-01

Are urinary BPA concentrations associated with in vitro fertilization (IVF) outcomes among women attending an academic fertility center? Urinary BPA concentrations were not associated with adverse reproductive and pregnancy outcomes among women from a fertility clinic. Bisphenol A (BPA), an endocrine disruptor, is detected in the urine of most Americans. Although animal studies have demonstrated that BPA reduces female fertility through effects on the ovarian follicle and uterus, data from human populations are scarce and equivocal. This prospective cohort study between 2004 and 2012 at the Massachusetts General Hospital Fertility Center included 256 women (n = 375 IVF cycles) who provided up to two urine samples prior to oocyte retrieval (total N = 673). Study participants were women enrolled in the Environment and Reproductive Health (EARTH) Study. Intermediate and clinical end-points of IVF treatments were abstracted from electronic medical records. We used generalized linear mixed models with random intercepts to evaluate the association between urinary BPA concentrations and IVF outcomes adjusted by age, race, body mass index, smoking status and infertility diagnosis. The specific gravity-adjusted geometric mean of BPA was 1.87 µg/l, which is comparable to that for female participants in the National Health and Nutrition Examination Survey, 2011-2012. Urinary BPA concentrations were not associated with endometrial wall thickness, peak estradiol levels, proportion of high quality embryos or fertilization rates. Furthermore, there were no associations between urinary BPA concentrations and implantation, clinical pregnancy or live birth rates per initiated cycle or per embryo transfer. Although we did not find any associations between urinary BPA concentrations and IVF outcomes, the relation between BPA and endometrial wall thickness was modified by age. Younger women (<37 years old) had thicker endometrial thickness across increasing quartiles of urinary BPA

The demography of words: The global decline in non-numeric fertility preferences, 1993-2011.

PubMed

Frye, Margaret; Bachan, Lauren

2017-07-01

This paper examines the decline in non-numeric responses to questions about fertility preferences among women in the developing world. These types of response-such as 'don't know' or 'it's up to God'-have often been interpreted through the lens of fertility transition theory as an indication that reproduction has not yet entered women's 'calculus of conscious choice'. However, this has yet to be investigated cross-nationally and over time. Using 19 years of data from 32 countries, we find that non-numeric fertility preferences decline most substantially in the early stages of a country's fertility transition. Using country-specific and multilevel models, we explore the individual- and contextual-level characteristics associated with women's likelihood of providing a non-numeric response to questions about their fertility preferences. Non-numeric fertility preferences are influenced by a host of social factors, with educational attainment and knowledge of contraception being the most robust and consistent predictors.

After the demographic transition: policy responses to low fertility in four Asian countries.

PubMed

Greenspan, A

1994-09-01

In the low fertility countries of South Korea, Taiwan, Singapore, and Thailand, policy-makers are concerned about the consequences of low growth. In South Korea, a family planning (FP) program was instituted in the early 1960s, and fertility declined to 1.6 by 1987. Rural fertility is still higher at 1.96, and abortion rates are high. 32.2% of fertility reduction is accomplished through abortion. South Korean population will not stabilize until 2021, at 50.6 million people. The elderly are expected to increase and strain housing, energy, and land resources. Government support for FP is being reduced, while private sector services are being enhanced. Government sterilization programs have been reduced significantly, and revisions in the Medical Insurance Law will cover part of contraceptive cost. Integrated services are being established. Many argue for an emphasis on birth spacing, child and family development, sex education, and care of the elderly. In Taiwan, replacement level fertility was reached in 1983. Policy in 1992 recommended increasing fertility from 1.6 to 2.1. The aim was to stabilize population without pronatalist interventions. Regardless of policy decisions, population growth will continue over the next 40 years, and the extent of aging will increase. In Singapore since the 1960s, the national government focused on encouraging small families through fertility incentives, mass media campaigns, and easy access to FP services. Fertility declined to 1.4 in 1988. Since 1983, government has established a variety of pronatalist incentives. In 1989, fertility increased to 1.8. The pronatalist shift is viewed as not likely to succeed in dealing with the concern for an adequate work force to support the elderly and economic development. In Thailand, fertility declined the fastest to 2.4 in 1993. The key factors were rapid economic and social development, a supportive cultural setting, strong demand for fertility control, and a successful FP program. The goal

Single nucleotide polymorphisms in candidate genes associated with fertilizing ability of sperm and subsequent embryonic development in cattle

USDA-ARS?s Scientific Manuscript database

Fertilization and development of the preimplantation embryo is under genetic control. The goal of the current study was to test 434 single nucleotide polymorphisms (SNPs) for association with genetic variation in fertilization and early embryonic development. The approach was to produce embryos from...

An analysis of social consequences of rapid fertility decline in China.

PubMed

Liu, Z; Liu, L

1988-12-01

Rapid fertility decline in China has brought about 2 direct effects: 1) the natural increase of the population has slowed down, and 2) the age structure has changed from the young to the adult type. These 2 effects have caused a series of economic and social consequences. Rapid fertility decline increases the gross national product per capita and accelerates the improvement of people's lives. Rapid fertility decline slows population growth and speeds up the accumulation of capital and the development of the economy. Since 1981, accumulation growth has exceeded consumption growth. Fertility decline alleviates the enrollment pressure on primary and secondary schools, raises the efficiency of education funds, and promotes the popularization of education. The family planning program strengthens the maternal and child health care and the medical care systems. As the result of economic development, the people's nutritional levels are improving. The physical quality of teenagers has improved steadily. The change in the age structure will alleviate the tension of rapid population growth and benefit population control in the next century. Fertility decline forces the traditional attitude toward childbearing from "more children, more happiness" to improved quality of children. The rapid fertility decline has caused a great deal of concern both inside and outside China about the aging of the population. The labor force, however, will continue to grow for the next 60 years. At present, China's population problems are still those of population growth.

Public policy, risk and fertility in Bangladesh: a comment.

PubMed

Robinson, W C

1983-09-01

In their report for the Planning Commission and the US Agency for International Development (USAID), Dhaka, Cain and Lieberman argue that Bangladesh's present family planning program efforts will be fruitless until some minimum level of economic security is provided for the nation's households. They specifically propose an employment guarantee scheme, but other approaches are also possible. The author estimates exactly how such an "economic risk" reducing scheme might be implemented by the government, how much it would cost, and its logical and empirical foundations. He offers 4 reasons for rejecting the idea. 1) The level of economic well being which would reduce fertility is unclear in their model, and it would not be a moderate income; at 250 Taka a month would a man feel secure, even if this were guaranteed to him and he believed the guarantee? 2) The cost to the government of even raising all presently unemployed, disabled, or aged indigent persons to slightly above the poverty level would be several times the yearly development budget. 3) The logical and theoretical underpinnings of the model appear confused and questionable. Cain's model of children as insurance against risk by guaranteeing future family income labor supply is not borne out by the historical evidence. The latter shows fertility has fallen slightly in response to growing economic pressure, not risen; that land owners have higher fertility than non-owners; that there is a substantial volume of unwanted fertility--not all births are viewed as functional or valuable; and that contraceptive rates are as high as 40% in parts of rural Bangladesh. 4) The following 2 data sets show that the empirical evidence for such a link between risk and fertility is negative: a) district level fertility data from the 1981 Census in conjunction with an index of "famine proneness" prepared by the Ministry of Food, and b) the Bangladesh Fertility Survey fertility and community characteristics data. The author

Noninvasive assays of in vitro matured human oocytes showed insignificant correlation with fertilization and embryo development.

PubMed

Ashourzadeh, Sareh; Khalili, Mohammad Ali; Omidi, Marjan; Mahani, Seyed Nooraldin Nematollahi; Kalantar, Seyed Mehdi; Aflatoonian, Abbas; Habibzadeh, Victoria

2015-08-01

Recently, the upgrading of in vitro maturation (IVM) of human oocytes as a promising strategy has emerged in assisted reproductive technology (ART). The goal was to evaluate the correlation of the in vitro matured oocytes selected on the basis of the zona pellucida (ZP) birefringence and meiotic spindles (MS) detection with fertilization and subsequent embryo development in ICSI program. A total of 168 immature oocytes [germinal vesicle (n = 140) and metaphase I (n = 28)] obtained from patients undergoing oocytes retrieval for ICSI. After in vitro culture for 24-40 h, 112 (67 %) oocytes reached to MII stage. Using a polarized microscopy, the presence of MS and ZP birefringence were assessed in matured oocytes, followed by ICSI performance. The rates of fertilization in oocytes with spindles (51.3 %) were similar to that of the oocytes without spindles (50.7 %; P = 1.00). Moreover, the fertilization rates in high birefringence (HB) oocytes was not statistically different than oocytes with low birefringence (LB) (P = 0.44). The findings also showed that 64.9 % of the fertilized oocytes developed to embryos, in which 33.3 % were derived from spindle-detected oocytes. Regarding the ZP birefringence, 35.5 % of the embryos were derived from HB oocytes. There were insignificant relationships between the MS detection and ZP birefringence score with the rates of fertilization and embryo development in IVM oocytes.

Modeling Spatial and Temporal Variability in Ammonia Emissions from Agricultural Fertilization

NASA Astrophysics Data System (ADS)

Balasubramanian, S.; Koloutsou-Vakakis, S.; Rood, M. J.

2013-12-01

Ammonia (NH3), is an important component of the reactive nitrogen cycle and a precursor to formation of atmospheric particulate matter (PM). Predicting regional PM concentrations and deposition of nitrogen species to ecosystems requires representative emission inventories. Emission inventories have traditionally been developed using top down approaches and more recently from data assimilation based on satellite and ground based ambient concentrations and wet deposition data. The National Emission Inventory (NEI) indicates agricultural fertilization as the predominant contributor (56%) to NH3 emissions in Midwest USA, in 2002. However, due to limited understanding of the complex interactions between fertilizer usage, farm practices, soil and meteorological conditions and absence of detailed statistical data, such emission estimates are currently based on generic emission factors, time-averaged temporal factors and coarse spatial resolution. Given the significance of this source, our study focuses on developing an improved NH3 emission inventory for agricultural fertilization at finer spatial and temporal scales for air quality modeling studies. Firstly, a high-spatial resolution 4 km x 4 km NH3 emission inventory for agricultural fertilization has been developed for Illinois by modifying spatial allocation of emissions based on combining crop-specific fertilization rates with cropland distribution in the Sparse Matrix Operator Kernel Emissions model. Net emission estimates of our method are within 2% of NEI, since both methods are constrained by fertilizer sales data. However, we identified localized crop-specific NH3 emission hotspots at sub-county resolutions absent in NEI. Secondly, we have adopted the use of the DeNitrification-DeComposition (DNDC) Biogeochemistry model to simulate the physical and chemical processes that control volatilization of nitrogen as NH3 to the atmosphere after fertilizer application and resolve the variability at the hourly scale

Effects of simulated weightlessness on meiosis. Fertilization, and early development in mice

NASA Technical Reports Server (NTRS)

Wolgemuth, D. J.

1986-01-01

The initial goal was to construct a clinostat which could support mammalian cell culture. The clinostat was selected as a means by which to simulate microgravity conditions within the laboratory, by constant re-orientation of cells with respect to the gravity vector. The effects of this simulated microgravity on in-vitro meiotic maturation of oocytes, using mouse as the model system, was investigated. The effects of clinostat rotation on fertilization in-vitro was then examined. Specific endpoints included examining the timely appearance of male and female pronuclei (indicating fertilization) and the efficiency of extrusion of the second polar body. Particular attention was paid to detecting anomalies of fertilization, including parthenogenetic activation and multiple pronuclei. Finally, for the preliminary studies on mouse embryogenesis, a key feature of the clinostat was modified, that of the position of the cells during rotation. A means was found to immobilize the cells during the clinostat reotation, permitting the cells to remain at the axis of rotation yet not interfering with cellular development.

The 'Own Children' fertility estimation procedure: a reappraisal.

PubMed

Avery, Christopher; St Clair, Travis; Levin, Michael; Hill, Kenneth

2013-07-01

The Full Birth History has become the dominant source of estimates of fertility levels and trends for countries lacking complete birth registration. An alternative, the 'Own Children' method, derives fertility estimates from household age distributions, but is now rarely used, partly because of concerns about its accuracy. We compared the estimates from these two procedures by applying them to 56 recent Demographic and Health Surveys. On average, 'Own Children' estimates of recent total fertility rates are 3 per cent lower than birth-history estimates. Much of this difference stems from selection bias in the collection of birth histories: women with more children are more likely to be interviewed. We conclude that full birth histories overestimate total fertility, and that the 'Own Children' method gives estimates of total fertility that may better reflect overall national fertility. We recommend the routine application of the 'Own Children' method to census and household survey data to estimate fertility levels and trends.

Effect of sperm entry on blastocyst development after in vitro fertilization and intracytoplasmic sperm injection - mouse model.

PubMed

Piotrowska-Nitsche, Karolina; Chan, Anthony W S

2013-01-01

To investigate whether in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), influence the embryo's development and its quality using the mouse as a model. Assisted fertilization was performed using ICSI and IVF. Fluorescent beads were adhered to the fertilization cone or place of previous sperm injection in the natural mated (NM), IVF and ICSI embryos, respectively. Embryo examination was carried out at the two-cell and blastocyst stage to determine the position of fluorescent bead. Protein expression was detected by fluorescence immunocytochemical staining and confocal microscopic imaging of blastocysts. IVF and ICSI embryos developed at rates comparable to NM group. Embryos show similar expression patterns of two transcription factors, Oct4 and Cdx2. The most preferred place for spermatozoa attachment was the equatorial site of the egg, whether fertilization occurred in vitro or under natural conditions. We also link the sperm entry position (SEP) to embryo morphology and the number of cells at the blastocyst stage, with no influence of the method of fertilization. IVF and ICSI, do not compromise in vitro pre-implantation development. Additional data, related to sperm entry, could offer further criteria to predict embryos that will implant successfully. Based on embryo morphology, developmental rate and protein expression level of key transcription factors, our results support the view that ART techniques, such as IVF and ICSI, do not perturb embryonic development or quality.

Adolescent Fertility: National File [Machine-Readable Data File].

ERIC Educational Resources Information Center

Moore, Kristin A.; And Others

This computer file contains recent cross sectional data on adolescent fertility in the United States for 1960, 1965, 1970, 1975 and 1980-85. The following variables are included: (1) births; (2) birth rates; (3) abortions; (4) non-marital childbearing; (5) infant mortality; and (6) low birth weight. Data for both teenagers and women aged 20-24 are…

Can we still learn something from the relationship between fertility and mother's employment? Evidence from developing countries.

PubMed

Cáceres-Delpiano, Julio

2012-02-01

In this work, I study the impact of fertility on mothers' employment for a sample of developing countries. Using the event of multiple births as an instrumental variable (IV) for fertility, I find that having children has a negative impact on female employment. In addition, three types of heterogeneity are found. First, the magnitude of the impact depends on the birth at which the increase in fertility takes place. Second, the types of jobs affected by a fertility shock (multiple births) are jobs identified with a higher degree of informality, such as self-employment or unpaid jobs. Finally, the heterogeneity analysis reveals that an unexpected change in fertility is stronger at a higher education level of the mother and in urban areas.

Claims for fertility interventions: a systematic assessment of statements on UK fertility centre websites

PubMed Central

Spencer, E A; Mahtani, K R; Goldacre, B; Heneghan, C

2016-01-01

Objectives Fertility services in the UK are offered by over 200 Human Fertilisation and Embryology Authority (HFEA)-registered NHS and private clinics. While in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) form part of the National Institute for Health and Care Excellence (NICE) guidance, many further interventions are offered. We aimed to record claims of benefit for interventions offered by fertility centres via information on the centres' websites and record what evidence was cited for these claims. Methods We obtained from HFEA a list of all UK centres providing fertility treatments and examined their websites. We listed fertility interventions offered in addition to standard IVF and ICSI and recorded statements about interventions that claimed or implied improvements in fertility in healthy women. We recorded which claims were quantified, and the evidence cited in support of the claims. Two reviewers extracted data from websites. We accessed websites from 21 December 2015 to 31 March 2016. Results We found 233 websites for HFEA-registered fertility treatment centres, of which 152 (65%) were excluded as duplicates or satellite centres, 2 were andrology clinics and 5 were unavailable or under construction websites. In total, 74 fertility centre websites, incorporating 1401 web pages, were examined for claims. We found 276 claims of benefit relating to 41 different fertility interventions made by 60 of the 74 centres (median 3 per website; range 0 to 10). Quantification was given for 79 (29%) of the claims. 16 published references were cited 21 times on 13 of the 74 websites. Conclusions Many fertility centres in the UK offer a range of treatments in addition to standard IVF procedures, and for many of these interventions claims of benefit are made. In most cases, the claims are not quantified and evidence is not cited to support the claims. There is a need for more information on interventions to be made available by fertility centres

Amphibian fertilization and development in microgravity

NASA Technical Reports Server (NTRS)

Souza, Kenneth A.

1993-01-01

chambers exposed to 1 g will be removed and observed within the GPWS using a dissecting microscope and camera system. On the basis of egg rotation and egg appearance, the 'best' and 'second best' frogs will be selected to contribute additional eggs. Using the two best frogs, 22 egg chambers will be loaded with eggs and fertilized. Eleven chambers wil be incubated at microgravity and eleven will be incubated on the centrifuge. At various times during the flight, chambers will be removed from the FEU and transferred to the GPWS where a formaldehyde-based fixative will be injected in order to preserve important developmental stages for in depth study following the flight. Five of the 22 chambers plus the eight fertilization test chambers will be returned to Earth with live tadpoles. The swimming behavior of these free swimming tadpoles will be examined within several hours of landing and some will be fixed for a detailed analysis of their inner ear, the otolity, the animals 'balance system.' Lychakov and Vinikov reported an increase in otolith size in tadpoles that developed (but were not fertilized) in space. Live tadpoles from the SL-J flight will be raised through metamorphsis for studies of maturation including an analysis of the effects of space flight on their ability to produce normal progency. Following the flight, the fixed embryos will be serially sectioned and stained using procedures that were developed for this experiment. The embroys fixed at the 2-4 cell stage will be examined for the distribution of cytoplasmic contents, including the various classes of yolk platelets, and the location and shape of the cleavage furrows. The gastrulae will be assessed for the normality of the complex cellular rearrangements that constitute blastopore formation and involution, i.e., the differentiation of the embryo into its specialized body parts. Using a new procedure, the gastrulae will be bleached which will enable the initial sperm entry point (SEP) to be located. The

Ocean fertilization, carbon credits and the Kyoto Protocol

NASA Astrophysics Data System (ADS)

Westley, M. B.; Gnanadesikan, A.

2008-12-01

Commercial interest in ocean fertilization as a carbon sequestration tool was excited by the December 1997 agreement of the Kyoto Protocol to the United Nations Convention on Climate Change. The Protocol commits industrialized countries to caps on net greenhouse gas emissions and allows for various flexible mechanisms to achieve these caps in the most economically efficient manner possible, including trade in carbon credits from projects that reduce emissions or enhance sinks. The carbon market was valued at 64 billion in 2007, with the bulk of the trading (50 billion) taking place in the highly regulated European Union Emission Trading Scheme, which deals primarily in emission allowances in the energy sector. A much smaller amount, worth $265 million, was traded in the largely unregulated "voluntary" market (Capoor and Ambrosi 2008). As the voluntary market grows, so do calls for its regulation, with several efforts underway to set rules and standards for the sale of voluntary carbon credits using the Kyoto Protocol as a starting point. Four US-based companies and an Australian company currently seek to develop ocean fertilization technologies for the generation of carbon credits. We review these plans through the lens of the Kyoto Protocol and its flexible mechanisms, and examine whether and how ocean fertilization could generate tradable carbon credits. We note that at present, ocean sinks are not included in the Kyoto Protocol, and that furthermore, the Kyoto Protocol only addresses sources and sinks of greenhouse gases within national boundaries, making open-ocean fertilization projects a jurisdictional challenge. We discuss the negotiating history behind the limited inclusion of land use, land use change and forestry in the Kyoto Protocol and the controversy and eventual compromise concerning methodologies for terrestrial carbon accounting. We conclude that current technologies for measuring and monitoring carbon sequestration following ocean fertilization

Fertility outcome and information on fertility issues in individuals with different forms of disorders of sex development: findings from the dsd-LIFE study.

PubMed

Słowikowska-Hilczer, Jolanta; Hirschberg, Angelica Lindén; Claahsen-van der Grinten, Hedi; Reisch, Nicole; Bouvattier, Claire; Thyen, Ute; Cohen Kettenis, Peggy; Roehle, Robert; Köhler, Birgit; Nordenström, Anna

2017-11-01

To investigate fertility outcome in individuals with different forms of disorders of sex development (DSD), if assisted reproductive technology (ART) was used, and the patients' satisfaction with the information they had received. A cross-sectional multicenter study, dsd-LIFE. Not applicable. A total of 1,040 patients aged ≥16 years with different DSD diagnoses participated. A web-based questionnaire was filled out by all participants. The participants could chose to take part in somatic investigations including ultrasonography. Information on partner, number of children, ART, adoption and step-children, general health, presence of gonads and uterus, current education and economic situation, received information on fertility issues, and satisfaction with the information, was collected. In the total cohort, mean age 32 years, 33% lived with a partner, but only 14% reported having at least one child including 7% with ART, 4% adopted. Only 3.5% of the total cohort had been able to reproduce without ART, most frequently women with congenital adrenal hyperplasia, and only 0.7% of participants with other diagnoses. Of the participants, 72% had received information on fertility, but 17% were not satisfied with the information. Fertility outcome is significantly reduced in all types of DSD; however, fertility potential should be assessed individually. The satisfaction with how fertility problems have been discussed can be improved. The care of patients with DSD is complex, should be individualized, and new treatment possibilities incorporated. A close collaboration in multidisciplinary teams is therefore essential to improve the situation for individuals with DSD. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Predicting Nitrogen in Streams: A Comparison of Two Estimates of Fertilizer Application

NASA Astrophysics Data System (ADS)

Mehaffey, M.; Neale, A.

2011-12-01

Decision makers frequently rely on water and air quality models to develop nutrient management strategies. Obviously, the results of these models (e.g., SWAT, SPARROW, CMAQ) are only as good as the nutrient source input data and recently the Nutrient Innovations Task Group has called for a better accounting of nonpoint nutrient sources. Currently, modelers frequently rely on county level fertilizer sales records combined with acreage of crops to estimate nitrogen sources from fertilizer for counties or watersheds. However, since fertilizer sales data are based on reported amounts they do not necessarily reflect actual use on the fields. In addition the reported sales data quality varies by state resulting in differing accuracy between states. In this study we examine an alternative method potentially providing a more uniform, spatially explicit, estimate of fertilizer use. Our nitrogen application data is estimated at a 30m pixel resolution which allows for scalable inputs for use in water and air quality models. To develop this dataset we combined raster data from the National Cropland data layer (CDL) data with the National Land Cover Data (NLCD). This process expanded the NLCD's 'cultivated crops' classes to included major grains, cover crops, and vegetable and fruits. The Agriculture Resource Management Survey chemical fertilizer application rate data were summarized by crop type and year for each state, encompassing the corn, soybean, spring wheat, and winter wheat crop types (ARMS, 2002-2005). The chemical fertilizer application rate data were then used to estimate annual application parameters for nitrogen, phosphate, potash, herbicide, pesticide, and total pesticide, all expressed on a mass-per-unit-crop-area basis for each state for each crop type. By linking crop types to nitrogen application rates, we can better estimate where applied fertilizer would likely be in excess of the amounts used by crops or where conservation practices may improve retention

Loss of Bmal1 decreases oocyte fertilization, early embryo development and implantation potential in female mice.

PubMed

Xu, Jian; Li, Yan; Wang, Yizi; Xu, Yanwen; Zhou, Canquan

2016-10-01

Biological clock genes expressed in reproductive tissues play important roles in maintaining the normal functions of reproductive system. However, disruption of female circadian rhythm on oocyte fertilization, preimplantation embryo development and blastocyst implantation potential is still unclear. In this study, ovulation, in vivo and in vitro oocyte fertilization, embryo development, implantation and intracellular reactive oxygen species (ROS) levels in ovary and oviduct were studied in female Bmal1+/+ and Bmal1-/- mice. The number of naturally ovulated oocyte in Bmal1-/- mice decreased (5.2 ± 0.8 vs 7.8 ± 0.8, P < 0.001), with an increasing abnormal oocyte ratio (20.4 ± 3.5 vs 11.7 ± 2.0%, P = 0.001) after superovulation. Significantly lower fertilization rate and obtained blastocyst number were observed in Bmal1-/- female mice either mated with wild-type in vivo or fertilized by sperm from wild-type male mice in vitro (all P < 0.05). Interestingly, in vitro fertilization rate of oocytes derived from Bmal1-/- increased significantly compared with in vivo study (P < 0.01). After transferring blastocysts derived from Bmal1+/+ and Bmal1-/- female mice to pseudopregnant mice, the implantation sites of the latter decreased 5 days later (8.0 ± 0.8 vs 5.3 ± 1.0, P = 0.005). The intracellular ROS levels in the ovary on proestrus day and in the oviduct on metestrus day increased significantly in Bmal1-/- mice compared with that of Bmal1+/+ mice. Deletion of the core biological clock gene Bmal1 significantly decreases oocyte fertilization rate, early embryo development and implantation potential in female mice, and these may be possibly caused by excess ROS levels generated in ovary and oviduct.

Fertility drugs and ovarian cancer.

PubMed

Ali, Aus Tariq

2017-06-20

The aetiology of ovarian cancer is multifactorial with both endogenous and exogenous risk factors playing an important role. The exact pathogenesis of ovarian cancer is still not well understood, despite the number of hypotheses published. Due to an increase in the number of women using fertility drugs, much attention has been focused on the long-term health effects of such drugs. Although fertility drugs facilitate the ovulation process, it is however associated with a significant increase in hormone concentrations, placing exposed women at increased risk of gynaecological cancer. Many clinical and epidemiological studies have examined the association between fertility drugs and ovarian cancer risk. Results from these studies have been contradictory, as some studies have reported an increased risk of ovarian cancer while others reported no increased risk. Nevertheless, recent studies have shown that women who used fertility drugs and did not conceive had a higher risk of developing ovarian cancer, compared to women who used fertility drugs and conceived and delivered successfully. This review discusses the effect of fertility drugs on the risk of developing ovarian cancer, providing details on four possible scenarios associated with fertility treatment. In addition, the limitations of previous studies and their impact on our understanding of the association between fertility drugs and ovarian cancer also have been highlighted. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Essential role of maternal UCHL1 and UCHL3 in fertilization and preimplantation embryo development

PubMed Central

Mtango, Namdori R.; Sutovsky, Miriam; Susor, Andrej; Zhong, Zhisheng; Latham, Keith E.; Sutovsky, Peter

2015-01-01

Posttranslational protein modification by ubiquitination, a signal for lysosomal or proteasomal proteolysis, can be regulated and reversed by deubiquitinating enzymes (DUBs). This study examined the roles of UCHL1 and UCHL3, two members of ubiquitin C-terminal hydrolase (UCH) family of DUBs, in murine fertilization and preimplantation development. Before fertilization, these proteins were associated with the oocyte cortex (UCHL1) and meiotic spindle (UCHL3). Intracytoplasmic injection of the general UCH-family inhibitor ubiquitin-aldehyde (UBAL) or antibodies against UCHL3 into mature metaphase II oocytes blocked fertilization by reducing sperm penetration of the zona pellucida and incorporation into the ooplasm, suggesting a role for cortical UCHL1 in sperm incorporation. Both UBAL and antibodies against UCHL1 injected at the onset of oocyte maturation (germinal vesicle stage) reduced the fertilizing ability of oocytes. The subfertile Uchl1gad−/− mutant mice showed an intriguing pattern of switched UCH localization, with UCHL3 replacing UCHL1 in the oocyte cortex. While fertilization defects were not observed, the embryos from homozygous Uchl1gad−/− mutant females failed to undergo morula compaction and did not form blastocysts in vivo, indicating a maternal effect related to UCHL1 deficiency. We conclude that the activity of oocyte UCHs contributes to fertilization and embryogenesis by regulating the physiology of the oocyte and blastomere cortex. PMID:21678411

Development of lucerne (Medicago sativa L.) treated with mineral fertilizer and manure at optimal and water deficit conditions.

PubMed

Vasileva, V; Kostov, O; Vasilev, E

2006-01-01

A study on the effect of different rates of mineral fertilizer and manure on yield parameters of lucerne under optimal and water deficit conditions was carried out. Leached chernozem soil and lucerne cultivar Victoria were used. The soil was treated with ammonium nitrate and fully matured cattle manure. The plants were grown under optimum moisture content of 80% and 40% of field capacity. The water deficit stress decreased top and root biomass by 11-75% and 3-29% at mineral and organic fertilization, respectively. The applied mineral and organic N strongly depressed nodules development. Both mineral fertilizer and organic manure at dose of 210 mg N kg(-1) soil completely inhibited the appearance of nodules. Next to nitrogen, water deficit stress further inhibited the development of nodules. Nitrogen fertilization increased seed productivity in the two experimental moisture conditions. The water deficit stress decreased seed productivity by 18 to 33% as compared to optimum conditions. The plant treatments with manure were much more resistant to water deficit and recovering ability of plants was faster as compared to treatments with mineral fertilizer. The application of manure stimulates development of drought-stress tolerance in lucerne. However, the results obtained can be considered for the soil type and experimental conditions used.

Constructing fertility tables for Soviet populations.

PubMed

Mazur, D P

1976-02-01

Because the 1970 Soviet Union census does not provide information on the age structure of men and women separately by sex and according to their ethnic affiliation, the 1959 USSR census data serve as the basis to infer knowledge about ethnic fertility. The model takes into account (1) the total number of births in 1960, estimated from the child-woman ratio in 1959, (2) the age structure of women in 1959, and (3) the assumed pattern of age-specific birth rates structured in terms of the modal age at childbearing and the length of the fertility age span. The results show that Ukrainians among the Slav populations ranked as the lowest with 2.07 children born per woman. Their total fertility contrasts with that of Kazakhs native to Central Asia, who reportedly according to Soviet sources had 7.46 children per woman in 1958-1959, and whose estimated rate is around 8.59 children. Extreme variations appear in the estimates of fertility among nationalities of the Caucasus region, Volga Basin, and to a lesser degree in Siberia. Official Soviet calculations of crude birth rates and age-specific rates for 15 Union Republics in 1967-1968 are transcribed and compared with the estimates for nationalities in 1959-1960. The same theoretical model used to generate the Soviet rates may be adapted under different assumptions to non-Soviet populations in other situations where the data are scanty or incomplete.

Claims for fertility interventions: a systematic assessment of statements on UK fertility centre websites.

PubMed

Spencer, E A; Mahtani, K R; Goldacre, B; Heneghan, C

2016-11-27

Fertility services in the UK are offered by over 200 Human Fertilisation and Embryology Authority (HFEA)-registered NHS and private clinics. While in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) form part of the National Institute for Health and Care Excellence (NICE) guidance, many further interventions are offered. We aimed to record claims of benefit for interventions offered by fertility centres via information on the centres' websites and record what evidence was cited for these claims. We obtained from HFEA a list of all UK centres providing fertility treatments and examined their websites. We listed fertility interventions offered in addition to standard IVF and ICSI and recorded statements about interventions that claimed or implied improvements in fertility in healthy women. We recorded which claims were quantified, and the evidence cited in support of the claims. Two reviewers extracted data from websites. We accessed websites from 21 December 2015 to 31 March 2016. We found 233 websites for HFEA-registered fertility treatment centres, of which 152 (65%) were excluded as duplicates or satellite centres, 2 were andrology clinics and 5 were unavailable or under construction websites. In total, 74 fertility centre websites, incorporating 1401 web pages, were examined for claims. We found 276 claims of benefit relating to 41 different fertility interventions made by 60 of the 74 centres (median 3 per website; range 0 to 10). Quantification was given for 79 (29%) of the claims. 16 published references were cited 21 times on 13 of the 74 websites. Many fertility centres in the UK offer a range of treatments in addition to standard IVF procedures, and for many of these interventions claims of benefit are made. In most cases, the claims are not quantified and evidence is not cited to support the claims. There is a need for more information on interventions to be made available by fertility centres, to support well-informed treatment

Fertility preservation during cancer treatment: clinical guidelines

PubMed Central

Rodriguez-Wallberg, Kenny A; Oktay, Kutluk

2014-01-01

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

Fertility awareness online: the efficacy of a fertility education website in increasing knowledge and changing fertility beliefs.

PubMed

Daniluk, J C; Koert, E

2015-02-01

How effective is online education in increasing knowledge of fertility and assisted reproductive technologies (ART), and changing beliefs about the timing of parenthood? Exposure to an online educational intervention resulted in immediate changes in participants' beliefs about the ideal timing of parenthood, and a significant increase in their knowledge of fertility and ART treatments and options; most of these changes were not sustained over time, particularly for men. Research has identified significant gaps in men's and women's knowledge of fertility and ART, contributing to the trend to delay childbearing. Effective educational programs need to be developed, to support informed fertility and child-timing decisions. Pre-post intervention study of 199 currently childless men and women, and a 6-month follow-up of 110 of these participants. One hundred and ninety-nine childless participants between the ages of 18 and 35 were asked to complete 4 beliefs and 22 knowledge questions prior to, and immediately after, reading 10 online posts related to: fertility testing and preservation, fertility history and lifespan, the effects of health and fitness on fertility, and assisted reproduction. Six months later, 110 of the original sample repeated the 26-item survey. Participants' fertility and ART knowledge scores increased significantly immediately after the intervention, as did their confidence in their fertility and ART knowledge. Participants' beliefs about the ideal and latest age a woman or man should consider producing a child decreased. However, 6 months later, participants' beliefs and knowledge levels largely returned to their pre-intervention levels, particularly for the men in the study. The sample size and the recruitment methods may limit the generalizability of these findings. Previous studies have demonstrated the short-term efficacy of online educational approaches to increase fertility knowledge and support informed family planning decisions. Web

Fertility awareness online: the efficacy of a fertility education website in increasing knowledge and changing fertility beliefs

PubMed Central

Daniluk, J.C.; Koert, E.

2015-01-01

STUDY QUESTION How effective is online education in increasing knowledge of fertility and assisted reproductive technologies (ART), and changing beliefs about the timing of parenthood? SUMMARY ANSWER Exposure to an online educational intervention resulted in immediate changes in participants' beliefs about the ideal timing of parenthood, and a significant increase in their knowledge of fertility and ART treatments and options; most of these changes were not sustained over time, particularly for men. WHAT IS KNOWN ALREADY Research has identified significant gaps in men's and women's knowledge of fertility and ART, contributing to the trend to delay childbearing. Effective educational programs need to be developed, to support informed fertility and child-timing decisions. STUDY DESIGN, SIZE, DURATION Pre-post intervention study of 199 currently childless men and women, and a 6-month follow-up of 110 of these participants. PARTICIPANTS/MATERIALS, SETTING, METHODS One hundred and ninety-nine childless participants between the ages of 18 and 35 were asked to complete 4 beliefs and 22 knowledge questions prior to, and immediately after, reading 10 online posts related to: fertility testing and preservation, fertility history and lifespan, the effects of health and fitness on fertility, and assisted reproduction. Six months later, 110 of the original sample repeated the 26-item survey. MAIN RESULTS AND THE ROLE OF CHANCE Participants' fertility and ART knowledge scores increased significantly immediately after the intervention, as did their confidence in their fertility and ART knowledge. Participants' beliefs about the ideal and latest age a woman or man should consider producing a child decreased. However, 6 months later, participants' beliefs and knowledge levels largely returned to their pre-intervention levels, particularly for the men in the study. LIMITATIONS, REASONS FOR CAUTION The sample size and the recruitment methods may limit the generalizability of these

Sea urchin egg fertilization and development

NASA Technical Reports Server (NTRS)

Young, R. S.

1971-01-01

The effects of subgravity (much less than unit gravity) on fertilization, cell division, differentiation, and growth of a relatively simple biological system (eggs of the sea urchin Arbacia punctulata) were considered. The experiment was flown on Gemini 3 and recovered as scheduled. However, the experiment objectives were not achieved, primarily for mechanical reasons.

DEVELOPMENT AND VALIDATION OF AN ION CHROMATOGRAPHIC METHOD FOR DETERMINING PERCHLORATE IN FERTILIZERS

EPA Science Inventory

A method has been developed for the determination of perchlorate in fertilizers. Materials are leached with deionized water to dissolve any soluble perchlorate compounds. Ion chromatographic separation is followed by suppressed conductivity for detection. Perchlorate is retained ...

Socioeconomic Status and Net Fertility during the Fertility Decline: A Comparative Analysis of Canada, Iceland, Sweden, Norway and the United States

PubMed Central

Dribe, Martin; Hacker, J. David; Scalone, Francesco

2014-01-01

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

The increase of the fertility of soils using the liquid organic fertilizers and fertilizers based on sugar-beet wastes.

NASA Astrophysics Data System (ADS)

Vyborova, Oxana

2010-05-01

The fertility of soil is a capacity for ensuring plants by water, nutrients, air and capacity for making optimal conditions for growth and development of plants. The result of it is a yield. The main characteristic of fertility of soil is maintenance of humus. The humus is important part of organic matter. The supporting of soil fertility is impossible by traditional methods. The amount of receiving mineral fertilizers in agriculture will not increase in future, because mineral fertilizers are very expensive. The mineral fertilizers don't influence on maintenance of total amount of humus in soil and improve the circulation of nutrients. Every hectare of fields have to receive no less than 8-10 tons of organic fertilizers, therefore we will have self-supporting balance of humus and the fertility of soils will be increasing. Consequently we are looking for new types of organic materials and we include them in modern agro technologies. One of them is an organomineral fertilizer (lignitic materials). The humic chemicals in the form of lignitic materials of natrium, potassium and ammonium are permitted for using them in agriculture at the beginning of 1984. The Department of agriculture in Russian Federation considered the problem of using humic chemicals and made a decision to use them on the fields of our country, because the lignitic materials can restore the fertility of our fields. The lignitic materials increase the amount of spore-forming bacteria, mold fungi and actinomycete. Therefore the organic decomposition occurs more strongly, the processes of humification increase the speed and the amount of humus rises in the soil. The new forming humus has a high biological activity and it improves chemical and physical soil properties. The addition of lignitic materials in soil activates different groups of microorganisms, which influence on mobilization of nutrients and transformation from potential to effective fertility. The inclusion of humic fertilizers improves

Hispanic fertility, immigration, and race in the twenty-first century

PubMed Central

Parrado, Emilio A.; Flippen, Chenoa A.

2012-01-01

In this paper we systematically describe the connection between immigration and fertility in light of the increasing nativist reaction to Hispanic groups. We follow a life-course perspective to directly link migration and fertility transitions. The analysis combines original qualitative and quantitative data collected in Durham/Chapel Hill, NC as well as national level information from the Current Population Survey. The qualitative data provides a person-centered approach to the connection between migration and fertility that we then extend in quantitative analyses. Results demonstrate that standard demographic measures that treat migration and fertility as separate processes considerably distort the childbearing experience of immigrant women, inflating fertility estimates for Hispanics as a whole. Once this connection is taken into consideration the fertility levels of Hispanic women are much lower than those reported with standard measures and the fertility-specific contribution of Hispanics to U.S. population growth is much reduced. PMID:23066430

miRNAs involved in the development and differentiation of fertile and sterile flowers in Viburnum macrocephalum f. keteleeri.

PubMed

Li, Weixing; He, Zhichong; Zhang, Li; Lu, Zhaogeng; Xu, Jing; Cui, Jiawen; Wang, Li; Jin, Biao

2017-10-13

Sterile and fertile flowers are important evolutionary developmental phenotypes in angiosperm flowers. The development of floral organs, critical in angiosperm reproduction, is regulated by microRNAs (miRNAs). However, the mechanisms underpinning the miRNA regulation of the differentiation and development of sterile and fertile flowers remain unclear. Here, based on investigations of the morphological differences between fertile and sterile flowers, we used high-throughput sequencing to characterize the miRNAs in the differentiated floral organs of Viburnum macrocephalum f. keteleeri. We identified 49 known miRNAs and 67 novel miRNAs by small RNA (sRNA) sequencing and bioinformatics analysis, and 17 of these known and novel miRNA precursors were validated by polymerase chain reaction (PCR) and Sanger sequencing. Furthermore, by comparing the sequencing results of two sRNA libraries, we found that 30 known and 39 novel miRNA sequences were differentially expressed, and 35 were upregulated and 34 downregulated in sterile compared with fertile flowers. Combined with their predicted targets, the potential roles of miRNAs in V. macrocephalum f. keteleeri flowers include involvement in floral organogenesis, cell proliferation, hormonal pathways, and stress responses. miRNA precursors and targets were further validated by quantitative real-time PCR (qRT-PCR). Specifically, miR156a-5p, miR156g, and miR156j expression levels were significantly higher in fertile flowers than in sterile flowers, while SPL genes displayed the opposite expression pattern. Considering that the targets of miR156 are predicted to be SPL genes, we propose that miR156 may be involved in the regulation of stamen development in V. macrocephalum f. keteleeri. We identified miRNAs differentially expressed between fertile and sterile flowers in V. macrocephalum f. keteleeri and provided new insights into the important regulatory roles of miRNAs in the differentiation and development of fertile and

The role of forest site in fertilizer response

Treesearch

Raymond E. Leonard; Albert L. Leaf; John V. Berglund; John V. Berglund

1972-01-01

A major task in developing a successful forest-fertilization program is the proper assessment of the site conditions and organism relations so that efficient site-dependent fertilizer prescriptions may be developed for the most effective and least wasteful use of fertilizer additives.

Cross-National Patterns of Intergenerational Continuities in Childbearing in Developed Countries

PubMed Central

Murphy, Michael

2013-01-01

Earlier work has shown that the association between the fertility of parents and the fertility of children has become stronger over time in some societies. This article updates and broadens the geographic coverage to assess the magnitude of intergenerational continuities in childbearing in developed and middle-income societies using data for 46 populations from 28 developed countries drawn from a number of recent large-scale survey programs. Robust positive intergenerational fertility correlations are found across these countries into the most recent period, and although there is no indication that the strength of the relationship is declining, the increasing trend does not appear to be continuing. PMID:24215254

Arbuscular mycorrhizal colonization in soil fertilized by organic and mineral fertilizers

NASA Astrophysics Data System (ADS)

Dvořáčková, Helena; Záhora, Jaroslav; Mikajlo, Irina; Elbl, Jakub; Kynický, Jindřich; Hladký, Jan; Brtnický, Martin

2017-04-01

The level of arbuscular mycorrhizal colonization of roots represents one of the best parameters for assessing soil quality. This special type of symbiosis helps plants to obtain nutrients of the distant area which are unavailable without cooperation with arbuscular mycorrhizal fungi. For example the plant available form of phosphorus is of the most important elements in plant nutrition. This element can't move (significantly) throw the soil and it could be unachievable for root system of plant. The same situation also applies to other important nutrients and water. Colonization of individual roots by arbuscular mycorrhizal fungi has a direct effect on the enlargement of the root system but plant needs to invest sugar substance for development of fungi. It's very difficult to understand when fungi colonization represents indicator of good soil condition. And when it provides us with information "about plant stress". The main goal of our work was to compare the effect of different fertilizers application on development of arbuscular mycorrhizal colonization. We worked with organic fertilizers such as biochar from residual biomass, biochar from sewage sludge and ageing biochar and with mineral fertilizer DAM 390 (mixture of ammonium 25 %, nitrate 25 % and urea nitrogen 50 %). Effect of different types of the above fertilizers on development of arbuscular mycorrhizal colonization was tested by pot experiment with indicator plant Lactuca sativa L. The highest (P < 0.05) colonization of roots was found in variant with biochar from sewage sludge. The lower colonization was recognized in control variant and variant with addition of mineral fertilizer. Our results indicate positive effect of modified biochar application to soil on increase in level of arbuscular mycorrhizal colonization of roots.

Demographic and fertility characteristics of 4 squatter settlements.

PubMed

Yusof, K; Zulkifli, S N

1985-01-01

The demographic and fertility profiles of 4 squatter areas, 2 with Sang Kancil, a community development project designed specifically for squatter settlements in Kuala Lumpur, are described. Data were taken from a census conducted in 1982. Figure 1 maps out the location of the study areas in the Federal Territory. The squatter household (5.4 members) varied little from the average Malaysian household. The average age of the male head of household was 40 years, i.e., not within the high fertility group; the mean duration of stay was 10 years. Household income/month averaged M$760, falling between estimates for urban and rural mean. Comparing the data on the 2 squatter areas, the non-Sang Kancil head of household was, on average, slightly older and had stayed about 2 years longer than his Sang Kancil counterpart. These differences were statistically significant. Both areas were comparable with regard to household income and size. Ethnically, the Sang Kancil areas were predominantly Malay, comprising 86% of total households. The control areas had a more mixed ethnic structure. From 1978-81, annual increases in total population had been fairly uniform, at around 2%, in non-Sang Kancil Areas. Yet, the Sang Kancil population experienced a growth spurt in 1980, which subsequently declined and appeared to level off. 1982 figures were disregarded in this analysis as they were based on a 1/2 year enumeration only. The age distribution pattern of all squatter areas combined was fairly similar to the national distribution pyramid but for a higher proportion of people in the 15-44 age group than national figures. The proportion of dependents, 0-14 years, was comparable despite having more people in this fertile age group. The proportion of infants (0-11 months) in the control population was constant, but there was a decline down to control values by the end of the surveyed period in the Sang Kancil group. In the toddler group, decreases were evident for both populations

Conference considers low fertility.

PubMed

1997-01-01

At present, at least 51 countries--representing 44% of the world's population--are showing below-replacement fertility rates. In some of these countries, where the number of new births is not adequate to replace aging populations, this trend is problematic. In other countries, most notably China, declining fertility has conferred significant benefits. At an Economic and Social Commission for Asia and the Pacific (ESCAP) Population Commission meeting held in New York in 1997, staff from China's State Statistical Bureau reported the country has a current total fertility rate of 1.8. The birth rate remains high, however, because of the large numbers of Chinese women in the 15-49 year reproductive age group (336 million in 1997). Also buffering the impact of a low fertility rate is a large labor surplus (130 million excess workers in rural China). To keep fertility below the replacement level, China plans to improve the quality of its family planning service, enhance poverty alleviation programs, and increase incentives for small families in rural areas. China's low fertility rate has provided an important impetus for economic development.

Correlations in fertility across generations: can low fertility persist?

PubMed

Kolk, Martin; Cownden, Daniel; Enquist, Magnus

2014-03-22

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.

Correlations in fertility across generations: can low fertility persist?

PubMed Central

Kolk, Martin; Cownden, Daniel; Enquist, Magnus

2014-01-01

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

The Impact of Soil Sampling Errors on Variable Rate Fertilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

R. L. Hoskinson; R C. Rope; L G. Blackwood

2004-07-01

Variable rate fertilization of an agricultural field is done taking into account spatial variability in the soil’s characteristics. Most often, spatial variability in the soil’s fertility is the primary characteristic used to determine the differences in fertilizers applied from one point to the next. For several years the Idaho National Engineering and Environmental Laboratory (INEEL) has been developing a Decision Support System for Agriculture (DSS4Ag) to determine the economically optimum recipe of various fertilizers to apply at each site in a field, based on existing soil fertility at the site, predicted yield of the crop that would result (and amore » predicted harvest-time market price), and the current costs and compositions of the fertilizers to be applied. Typically, soil is sampled at selected points within a field, the soil samples are analyzed in a lab, and the lab-measured soil fertility of the point samples is used for spatial interpolation, in some statistical manner, to determine the soil fertility at all other points in the field. Then a decision tool determines the fertilizers to apply at each point. Our research was conducted to measure the impact on the variable rate fertilization recipe caused by variability in the measurement of the soil’s fertility at the sampling points. The variability could be laboratory analytical errors or errors from variation in the sample collection method. The results show that for many of the fertility parameters, laboratory measurement error variance exceeds the estimated variability of the fertility measure across grid locations. These errors resulted in DSS4Ag fertilizer recipe recommended application rates that differed by up to 138 pounds of urea per acre, with half the field differing by more than 57 pounds of urea per acre. For potash the difference in application rate was up to 895 pounds per acre and over half the field differed by more than 242 pounds of potash per acre. Urea and potash

Impact of ketorolac administration around ovarian stimulation on in vivo and in vitro fertilization and subsequent embryo development.

PubMed

Jee, Byung Chul; Youm, Hye Won; Lee, Jae Ho; Kim, Jee Hyun; Suh, Chang Suk; Kim, Seok Hyun

2013-05-01

We performed this study to investigate the effect of ketorolac (a non-steroidal anti-inflammatory drug) administration around ovarian stimulation on in vivo and in vitro fertilization process. Sixty-four female mice (ICR) were injected with ketorolac (0, 7.5, 15 and 30 µg/d) for 3 d starting from the day of eCG treatment. In experiment 1, 41 mice were triggered by hCG and then mated; two-cell embryos were obtained and in vitro development up to blastocyst was observed. In experiment 2, 23 mice were triggered by hCG and mature oocytes were collected; in vitro fertilization rate and subsequent embryo development up to blastocyst was recorded. In experiment 1, the blastocyst-forming rates per in vivo fertilized two-cell embryo showed an inverse relationship with a dosage of ketorolac (97.6%, 64.2%, 35.4% and 25.9%). In experiment 2, degenerated oocytes were frequently observed in a dose-dependent manner (4.3%, 22.9%, 22.4% and 75.0%). Lower fertilization rates were noted in all the three ketorolac-treating groups; blastocyst-forming rate was significantly lower in 30-µg-treating group when compared with the control group. Administration of ketorolac around ovarian stimulation significantly affects the development of in vivo fertilized embryo in a dose-dependent manner. High-dose ketorolac could result in a poor oocyte quality and decreased embryo developmental competence.

HINDU-MUSLIM FERTILITY DIFFERENTIAL IN INDIA: A COHORT APPROACH.

PubMed

Pasupuleti, Samba Siva Rao; Pathak, Prasanta; Jatrana, Santosh

2017-03-01

Hindus and Muslims together account for 94% of the population of India. The fertility differential between these two religious groups is a sensitive and hotly debated issue in political and academic circles. However, the debate is mostly based on a period approach to fertility change, and there have been some problems with the reliability of period fertility data. This study investigated cohort fertility patterns among Hindus and Muslims and the causes of the relatively higher level of fertility among Muslims. Data from the three National Family Health Surveys conducted in India since the early 1990s were analysed using a six-parameter special form of the Gompertz model and multiple linear regression models. The results show a gap of more than 1.3 children per woman between those Muslim and Hindu women who ended/will end their reproductive period in the calendar years 1993 to 2025. The socioeconomic and demographic characteristics of Muslims explain 31.2% of the gap in fertility between Muslims and Hindus, while the desire for more children among Muslims explains an additional 18.2% of the gap in fertility.

Critical Perspectives on Schooling and Fertility in the Developing World.

ERIC Educational Resources Information Center

Bledsoe, Caroline H., Ed.; Casterline, John B., Ed.; Johnson-Kuhn, Jennifer A., Ed.; Haaga, John G., Ed.

The assumption of a causal relationship between more schooling and lower fertility for women has led many governments to support women's education. However, understanding the nature and strength of the relationship between education and fertility remains a central challenge for scholars seeking to explain demographic and social change and for…

Development and evolution of the female gametophyte and fertilization process in Welwitschia mirabilis (Welwitschiaceae).

PubMed

Friedman, William E

2015-02-01

The female gametophyte of Welwitschia has long been viewed as highly divergent from other members of the Gnetales and, indeed, all other seed plants. However, the formation of female gametes and the process of fertilization have never been observed. Standard histological techniques were applied to study gametophyte development and the fertilization process in Welwitschia. In Welwitschia, fertilization events occur when pollen tubes with binucleate sperm cells grow down through the nucellus and encounter prothallial tubes, free nuclear tubular extensions of the micropylar end of the female gametophyte that grow up through the nucellus. Entry of a binucleate sperm cell into a vacuolate prothallial tube appears to stimulate the rapid coagulation of cytoplasm around a single female nucleus, which differentiates into an egg cell. One sperm nucleus enters the female gamete, while the second sperm nucleus remains outside and ultimately degenerates. Only a single fertilization event occurs per mating pair of pollen tube and prothallial tube. Welwitschia lacks the gnetalean pattern of regular double fertilization, as found in Ephedra and Gnetum, involving sperm from a single pollen tube to yield two zygotes. Moreover, an analysis of character evolution indicates that the female gametophyte of Welwitschia is highly apomorphic both among seed plants, and specifically within Gnetales, but also shares several key synapomorphies with its sister taxon Gnetum. Finally, the biological role of prothallial tubes in Welwitschia is examined from the perspectives of gamete competition and kin conflict. © 2015 Botanical Society of America, Inc.

International Fertility Change: New Data and Insights from the Developmental Idealism Framework

PubMed Central

Thornton, Arland; Binstock, Georgina; Yount, Kathryn M.; Abbasi-Shavazi, Mohammad Jalal; Ghimire, Dirgha; Xie, Yu

2012-01-01

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 fertility declines foster development. Many also expect and endorse future declines in fertility. PMID:22403035

Vitrification, in vitro fertilization, and development of Atg7 deficient mouse oocytes.

PubMed

Bang, Soyoung; Lee, Geun-Kyung; Shin, Hyejin; Suh, Chang Suk; Lim, Hyunjung Jade

2016-03-01

Autophagy contributes to the clearance and recycling of macromolecules and organelles in response to stress. We previously reported that vitrified mouse oocytes show acute increases in autophagy during warming. Herein, we investigate the potential role of Atg7 in oocyte vitrification by using an oocyte-specific deletion model of the Atg7 gene, a crucial upstream gene in the autophagic pathway. Oocyte-specific Atg7 deficient mice were generated by crossing Atg7 floxed mice and Zp3-Cre transgenic mice. The oocytes were vitrified-warmed and then subjected to in vitro fertilization and development. The rates of survival, fertilization, and development were assessed in the Atg7 deficient oocytes in comparison with the wildtype oocytes. Light chain 3 (LC3) immunofluorescence staining was performed to determine whether this method effectively evaluates the autophagy status of oocytes. The survival rate of vitrified-warmed Atg7(f/f) ;Zp3-Cre (Atg7(d/d) ) metaphase II (MII) oocytes was not significantly different from that of the wildtype (Atg7(f/f) ) oocytes. Fertilization and development in the Atg7(d/d) oocytes were significantly lower than the Atg7(f/f) oocytes, comparable to the Atg5(d/d) oocytes previously described. Notably, the developmental rate improved slightly in vitrified-warmed Atg7(d/d) MII oocytes when compared to fresh Atg7(d/d) oocytes. LC3 immunofluorescence staining showed that this method can be reliably used to assess autophagic activation in oocytes. We confirmed that the LC3-positive signal is nearly absent in Atg7(d/d) oocytes. While autophagy is induced during the warming process after vitrification of MII oocytes, the Atg7 gene is not essential for survival of vitrified-warmed oocytes. Thus, induction of autophagy during warming of vitrified MII oocytes seems to be a natural response to manage cold or other cellular stresses.

Microgravity effects during fertilization, cell division, development, and calcium metabolism in sea urchins

NASA Technical Reports Server (NTRS)

Schatten, Heide

1996-01-01

The overall objectives of this project are to explore the role of microgravity during fertilization, early development, cytoskeletal organization, and skeletal calcium deposition in a model development system: the sea urchin eggs and embryos. While pursuing these objectives, we have also helped to develop, test, and fly the Aquatic Research Facility (ARF) system. Cells were fixed at preselected time points to preserve the structures and organelles of interest with regards to cell biology events during development. The protocols used for the analysis of the results had been developed during the earlier part of this research and were applied for post-flight analysis using light and (immuno)fluorescence microscopy, scanning electron microscopy, and transmission electron microscopy. The structures of interest are: microtubules during fertilization, cell division, and cilia movement; microfilaments during cell surface restructuring and cell division; centrosomes and centrioles during cell division, cell differentiation, and cilia formation and movement; membranes, Golgi, endoplasmic reticulum, mitochondria, and chromosomes at all stages of development; and calcium deposits during spicule formation in late-stage embryos. In addition to further explore aspects important or living in space, several aspects of this research are also aimed at understanding diseases that affect humans on Earth which may be accelerated in space.

FERTILIZERS SALES AND SERVICE. AGRICULTURAL SUPPLY - SALES AND SERVICE OCCUPATIONS, MODULE NUMBER 9.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. Center for Vocational and Technical Education.

THE PURPOSE OF THIS GUIDE IS TO ASSIST TEACHERS IN PREPARING HIGH SCHOOL AND POST-HIGH SCHOOL STUDENTS FOR AGRICULTURAL SUPPLY OCCUPATIONS. ONE OF A SERIES, THIS MODULE WAS DEVELOPED ON THE BASIS OF STATE STUDIES BY A NATIONAL TASK FORCE. THE SPECIFIC OBJECTIVE IS TO PREPARE STUDENTS FOR ENTRY AND ADVANCEMENT IN FERTILIZER SALES AND SERVICE.…

Fertility of men and women aged 15-44 years in the United States: National Survey of Family Growth, 2006-2010.

PubMed

Martinez, Gladys; Daniels, Kimberly; Chandra, Anjani

2012-04-12

This report presents national estimates of the fertility of men and women aged 15-44 years in the United States in 2006-2010 based on the National Survey of Family Growth (NSFG). Data are compared with similar measures for 2002. Descriptive tables of numbers, percentages, and means are presented and discussed. Data were collected through in-person interviews of a nationally representative sample of the household population aged 15-44 years in the United States between July 2006 and June 2010. The 2006-2010 NSFG sample is comprised of 22,682 respondents including 10,403 men and 12,279 women. The overall response rate for the 2006-2010 NSFG was 77%, 75% for men and 78% for women. Many of the fertility measures among men and women aged 15-44 based on the 2006-2010 NSFG were generally similar to those reported based on the 2002 NSFG. The mean age at first child's birth for women was 23 and the mean age at first child's birth for men was 25. One-half of first births to women were in their 20s and two-thirds of first births were fathered by men who were in their 20s. On average, women aged 15-44 have 1.3 children as of the time of the interview. By age 40, 85% of women had had a birth, and 76% of men had fathered a child. In 2006-2010, 22% of first births to women occurred within cohabiting unions, up from 12% in 2002. These measures differed by Hispanic origin and race and other demographic characteristics.

Tracking the development of the petaloid fertile stamen in Canna indica: insights into the origin of androecial petaloidy in the Zingiberales.

PubMed

Almeida, Ana M R; Brown, Andrew; Specht, Chelsea D

2013-01-01

Flowers of the order Zingiberales demonstrate a remarkable trend of reduction in the number of fertile stamens; from five or six fertile, filamentous stamens bearing two thecae each in Musaceae and Strelitziaceae to just a single petaloid stamen bearing a single theca in Cannaceae and Marantaceae. As one progresses from ancestral to derived floral forms, 5-6 fertile stamens are replaced by 4-5 petaloid staminodes. In Cannaceae and Costaceae, all members of the androecial whorls exhibit petaloidy, including the fertile stamen. In Costaceae, a single fertile stamen develops two thecae embedded on a broad petaloid appendage, while in Cannaceae the single fertile stamen is further reduced to a single theca with a prominent, expanded petaloid appendage. Whether petaloidy of the fertile stamen is a synapomorphy of the entire ginger clade (including Cannaceae, Costaceae, Zingiberaceae and Marantaceae), or the result of independent convergent evolution in Cannaceae, Costaceae, and some Zingiberaceae, is unclear. We combine a developmental series of the formation of the petaloid fertile stamen in Canna indica with data on the expression of B- and C-class floral organ identity genes to elucidate the organogenetic identity of the petaloid stamen and staminodes. Our data indicate that the single fertile theca in C. indica and its petaloid appendage are derived from one-half of the primordium of a single stamen, with no contribution from the remaining part of the stamen (i.e. the second theca primordium) which aborts early in development. The petaloid appendage expands later, and develops from the position of the filament/connective of the developing theca. Floral identity gene expression shows that petal identity genes (i.e. B-class genes) are expressed in all floral organs studied while C-class gene AG-1 is expressed in an increasing gradient from sepals to gynoecium, and AG-2 is expressed in all floral organs except the petals. The canonical model for molecular specification

Is Low Fertility Really a Problem? Population Aging, Dependency, and Consumption*

PubMed Central

2015-01-01

Longer lives and fertility far below the replacement level of 2.1 births per woman are leading to rapid population aging in many countries. Many observers are concerned that aging will adversely affect public finances and standards of living. Analysis of newly available National Transfer Accounts data for 40 countries shows that fertility well above replacement would typically be most beneficial for government budgets. However, fertility near replacement would be most beneficial for standards of living when the analysis includes the effects of age structure on families as well as governments. And fertility below replacement would maximize per capita consumption when the cost of providing capital for a growing labor force is taken into account. While low fertility will indeed challenge government programs and very low fertility undermines living standards, we find that moderately low fertility and population decline favor the broader material standard of living PMID:25301626

An improved Brass correlational fertility model.

PubMed

Zhang, E; Chen, J

1995-01-01

Demographers have for years tried to establish a mathematical model capable of accurately describing patterns of fertility change. William Brass's Gompertz correlational fertility model is based upon a standard age-specific fertility pattern correlated to the age-specific fertility rate of the area under study with the purpose of simulating the actual age-specific fertility rate of the area. While the Brass correlational fertility model has solved many problems in quantitative studies of fertility and has been applied in population simulation and prediction, it has been unsatisfactory in analyzing fertility changes in China. The authors therefore developed a parity-specific correlational model to better reflect the situation of rapid fertility decline in China. This modified model better describes the impact of current family planning policy in China. Moreover, satisfactory results can be obtained by simulating and analyzing fertility in recent years, and major parameters can be identified by using demographically definite and readily manageable indicators. These indicators can clearly reflect the goals of the country's family planning policy, such as the average age at child-bearing, median age at child-bearing, early reproduction ratio, and percentage of the second child.

Low temperatures are required to induce the development of fertile flowers in transgenic male and female early flowering poplar (Populus tremula L.)

PubMed Central

Hoenicka, Hans; Lehnhardt, Denise; Briones, Valentina; Nilsson, Ove; Fladung, Matthias

2016-01-01

Until now, artificial early flowering poplar systems have mostly led to the development of sterile flowers. In this study, several strategies aimed at inducting fertile flowers in pHSP::AtFT transgenic poplar were evaluated, in particular the influence of temperature and photoperiod. Our results provide evidence that temperature, and not photoperiod, is the key factor required for the development of fertile flowers in early flowering poplar. Fertile flowers were only obtained when a cold treatment phase of several weeks was used after the heat treatment phase. Heat treatments induced AtFT gene activity through activation of the heat-shock promoter (pHSP). Photoperiod did not show a similar influence on flower fertility as pollen grains were obtained under both long- and short-day conditions. Fertility was confirmed in flowers of both male and female plants. For the first time, crosses were successfully performed with transgenic female early flowering poplar. All mature flowers obtained after 8 weeks of inductive treatments were fertile. Gene expression studies also confirmed that cold temperatures influenced expression of poplar genes homologous to ‘pollen development genes’ from Arabidopsis thaliana (L.) Heynh. Homology and expression patterns suggested a role for PtTDF1, PtBAM1, PtSERK1/2 and PtMS1 on anther and pollen development in poplar flowers. The system developed in this study allows a fast and very reliable induction of fertile poplar flowers in a very short period of time. The non-reproductive phase, usually 7–10 years, can now be shortened to 6–10 months, and fertile flowers can be obtained independently of the season. This system is a reliable tool for breeding purposes (high-speed breeding technology), genomics and biosafety research. PMID:27052434

Low temperatures are required to induce the development of fertile flowers in transgenic male and female early flowering poplar (Populus tremula L.).

PubMed

Hoenicka, Hans; Lehnhardt, Denise; Briones, Valentina; Nilsson, Ove; Fladung, Matthias

2016-05-01

Until now, artificial early flowering poplar systems have mostly led to the development of sterile flowers. In this study, several strategies aimed at inducting fertile flowers in pHSP::AtFT transgenic poplar were evaluated, in particular the influence of temperature and photoperiod. Our results provide evidence that temperature, and not photoperiod, is the key factor required for the development of fertile flowers in early flowering poplar. Fertile flowers were only obtained when a cold treatment phase of several weeks was used after the heat treatment phase. Heat treatments induced AtFT gene activity through activation of the heat-shock promoter (pHSP). Photoperiod did not show a similar influence on flower fertility as pollen grains were obtained under both long- and short-day conditions. Fertility was confirmed in flowers of both male and female plants. For the first time, crosses were successfully performed with transgenic female early flowering poplar. All mature flowers obtained after 8 weeks of inductive treatments were fertile. Gene expression studies also confirmed that cold temperatures influenced expression of poplar genes homologous to 'pollen development genes' from Arabidopsis thaliana (L.) Heynh. Homology and expression patterns suggested a role for PtTDF1, PtBAM1, PtSERK1/2 and PtMS1 on anther and pollen development in poplar flowers. The system developed in this study allows a fast and very reliable induction of fertile poplar flowers in a very short period of time. The non-reproductive phase, usually 7-10 years, can now be shortened to 6-10 months, and fertile flowers can be obtained independently of the season. This system is a reliable tool for breeding purposes (high-speed breeding technology), genomics and biosafety research. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The World Fertility Survey: Charting Global Childbearing.

ERIC Educational Resources Information Center

Lightbourne, Robert, Jr.; And Others

1982-01-01

Reported in this bulletin are major results from an ongoing study conducted by the World Fertility Survey (WFS) to examine fertility levels and trends and contraceptive use in developing and developed countries. Major results were available by early 1982 from 29 developing countries and 16 developed countries. These results indicated that while…

The cell biology of mammalian fertilization.

PubMed

Okabe, Masaru

2013-11-01

Fertilization is the process by which eggs and spermatozoa interact, achieve mutual recognition, and fuse to create a zygote, which then develops to form a new individual, thus allowing for the continuity of a species. Despite numerous studies on mammalian fertilization, the molecular mechanisms underpinning the fertilization event remain largely unknown. However, as I summarize here, recent work using both gene-manipulated animals and in vitro studies has begun to elucidate essential sperm and egg molecules and to establish predictive models of successful fertilization.

Soils, Crops and Fertilizer Use. A What, How and Why Guide. Appropriate Technologies for Development. Reprint R-8.

ERIC Educational Resources Information Center

Leonard, David

This manual, prepared for use by Peace Corps volunteers in developing countries, has been designed as an on-the-job reference for soil management and fertilizer use at the small farmer level. It provides information on yield-boosting techniques, especially in the areas of soil conservation, organic and chemical fertilizer use, and the safe and…

Nuclear lamins during gametogenesis, fertilization and early development

NASA Technical Reports Server (NTRS)

Maul, G. G.; Schatten, G.

1986-01-01

The distribution of lamins (described by Gerace, 1978, as major proteins of nuclear envelope) during gametogenesis, fertilization, and early development was investigated in germ cells of a mouse (Mus musculus), an echinoderm (Lytechinus variegatus), and the surf clam (Spisula solidissima) was investigated in order to determine whether the differences detected could be correlated with differences in the function of cells in these stages of the germ cells. In order to monitor the behavior of lamins, the gametes and embryos were labeled with antibodies to lamins A, C, and B extracted from autoimmune sera of patients with scleroderma and Lupus erythematosus. Results indicated that lamin B could be identified in nuclear envelopes on only those nuclei where chromatin is attached and where RNA synthesis takes place.

Population waves and fertility fluctuations: social security implications.

PubMed

Boyle, P P; Freedman, R

1985-01-01

Based on Canadian data, this study discusses some of the methods which incorporate fertility variations into population forecasts. In particular, the relative shifts in the age structure which can have profound social and economic consequences on the context of a pay as you go national security system are analyzed. In terms of long range economic and social planning, oscillating growth projections are much more difficult to handle and plan for than the constant growth rates predicted by stable population theories. The impact of different types of fertility fluctuations are analyzed in terms of evolution of the dependency ration over time; the dependency ratio corresponds to the ratio of the retired lives of a population to those of the working age population. From the viewpoint of a social security system, the evolution of the dependency ratio over time is of particular importance. Other areas explored are: 1) cohort fertility variations; 2) periodic fertility fluctuations; and 3) limit cycle behaviors. In the context of a national social security plan, one possible response to the population projections would be to maintain the year by year level of the RA ratio (ratio of the population aged 65 and over to the population aged between 20 and 65) at its equilibrium value of 27.6% by adjusting the retirement age appropriately.

Development of a diverse epiphyte community in response to phosphorus fertilization.

PubMed

Benner, Jon W; Vitousek, Peter M

2007-07-01

The role of terrestrial soil nutrient supply in determining the composition and productivity of epiphyte communities has been little investigated. In a montane Hawaiian rainforest, we documented dramatic increases in the abundance and species richness of canopy epiphytes in a forest that had been fertilized annually with phosphorus (P) for 15 years; there was no response in forest that had been fertilized with nitrogen (N) or other nutrients. The response of N-fixing lichens to P fertilization was particularly strong, although mosses and non-N-fixing lichens also increased in abundance and diversity. We show that enhancement of canopy P availability is the most likely factor driving the bloom in epiphytes. These results provide strong evidence that terrestrial soil fertility may structure epiphyte communities, and in particular that the abundance of N-fixing lichens--a functionally important epiphyte group--may be particularly sensitive to ecosystem P availability.

Preservation of Fertility Potential for Gender and Sex Diverse Individuals.

PubMed

Johnson, Emilie K; Finlayson, Courtney

2016-01-01

Gender and sex diverse individuals-transgender individuals and those with disorders of sex development (DSD)-both face medical treatments that may impair biological fertility potential. Young DSD patients also often have abnormal gonadal development. Fertility preservation for these populations has historically been poorly understood and rarely addressed. Future fertility should be discussed with gender and sex diverse individuals, particularly given recent advances in fertility preservation technologies and evolving views of fertility potential. Key ethical issues include parental proxy decision-making and uncertainty regarding prepubertal fertility preservation technologies. Many opportunities exist for advancing fertility-related care and research for transgender and DSD patients.

Contemporary Fertility Patterns and First-Birth Timing among Mexican-Origin Women

ERIC Educational Resources Information Center

Batson, Christie D.

2013-01-01

This article examines first-birth timing among Mexican women in the United States over two birth cohorts. Currently, Mexican women are one of a small group that maintains above-replacement fertility in the United States, contributing to both Mexican population growth and overall national population growth. Yet, the fertility timing of Mexican…

The effect of immature oocytes quantity on the rates of oocytes maturity and morphology, fertilization, and embryo development in ICSI cycles.

PubMed

Halvaei, Iman; Ali Khalili, Mohammad; Razi, Mohammad Hossein; Nottola, Stefania A

2012-08-01

The goal was to evaluate the role of the number of retrieved immature oocytes on mature oocyte counts and morphology, and also the rates of fertilization and embryo development in ICSI cycles. 101 ICSI cycles were included in this prospective evaluation. Patients were divided into 2 groups of A (≤ 2 immature oocytes) and B (> 2 immature oocytes). In sub-analysis, the impacts of the number of GV and MI oocytes were assessed on the rates of fertilization and embryo development. Also, correlations between the numbers of immature and mature oocytes, as well as maternal age between two groups were analyzed. Assessments of oocyte morphology, fertilization, embryo quality and development were done accordingly. There was no correlation between the immature oocytes quantity with the number of mature ones. There were insignificant differences for embryo development between two groups, but fertilization rate was higher in group A (P = 0.03). In sub-analysis, insignificant differences were observed between two groups of ≤ and >2 GV and MI oocytes for rates of fertilization and embryo development. Also, the rates of clinical pregnancy and delivery were insignificant between groups. The rate of morphologically abnormal oocytes had no significant difference between two groups, except for wide perivitelline space (PVS) which was higher in group A (P = 0.03). There was no significant difference for maternal age between two groups. In cases with few retrieved immature oocytes, rates of fertilization and incidence of wide PVS may increase, although immature oocytes may not have any negative impacts on early embryo development, or the rates on number of mature oocytes.

Young women's perceptions of fertility-related information and fertility distress before surgery for ovarian cysts.

PubMed

Lind, Tekla; Lampic, Claudia; Hammarström, Margareta; Rodriguez-Wallberg, Kenny

2013-11-01

To investigate young women's reproductive desire and perceptions of fertility-related information when scheduled for ovarian cyst surgery with a possible impact on fertility. Cross-sectional study. University Hospital. Women of reproductive age (n = 106, mean age 32.3 years, range 18-44 years) with a diagnosis of ovarian cyst and scheduled ovarian cyst surgery between March 2011 and September 2012 were included. The women answered a questionnaire after the presurgery consultation with the gynecologist. The questionnaire included study-specific measures of reproductive desire, perception of fertility-related information received, worry about future fertility and sociodemographic characteristics. Reproductive desire and recalled information on the impact of surgery on fertility. A high proportion of the women (72%) reported a desire for having children in the future and more than half of them (58%) recalled receiving information about the impact of surgery on fertility. In a multivariable logistic regression model adjusted for parity, education and age, a desire to have children increased the likelihood of recalling having received fertility-related information (odds ratio 3.2, 95% CI 1.1-9.2). Almost half of women with reproductive desire had ovarian surgery without recalling a discussion of fertility issues. Development of written information or interactive information might improve women's perception of fertility-related information. © 2013 Nordic Federation of Societies of Obstetrics and Gynecology.

Representing growth response to fertilization in the Prognosis Model for Stand Development

Treesearch

Albert R. Stage; Nicholas L. Crookston; Bahman Shafii; James A. Moore; John Olson

1990-01-01

Capability to represent effects of fertilization has been added to the Prognosis Model for Stand Development. As implemented in version 6, the extension is calibrated only for applications of 200 lb nitrogen applied in the form of urea. Direct and indirect effects are based on growth 10 years after treatment for diameter effects, and 6 years after treatment for height...

Development of a biologically based fertilizer, incorporating Bacillus megaterium A6, for improved phosphorus nutrition of oilseed rape.

PubMed

Hu, Xiaojia; Roberts, Daniel P; Xie, Lihua; Maul, Jude E; Yu, Changbing; Li, Yinshui; Zhang, Shujie; Liao, Xing

2013-04-01

Sustainable methods with diminished impact on the environment need to be developed for the production of oilseed rape in China and other regions of the world. A biological fertilizer consisting of Bacillus megaterium A6 cultured on oilseed rape meal improved oilseed rape seed yield (P < 0.0001) relative to the nontreated control in 2 greenhouse pot experiments using natural soil. This treatment resulted in slightly greater yield than oilseed rape meal without strain A6 in 1 of 2 experiments, suggesting a role for strain A6 in improving yield. Strain A6 was capable of solubilizing phosphorus from rock phosphate in liquid culture and produced enzymes capable of mineralizing organic phosphorus (acid phosphatase, phytase) in liquid culture and in the biological fertilizer. The biologically based fertilizer, containing strain A6, improved plant phosphorus nutrition in greenhouse pot experiments resulting in significantly greater available phosphorus in natural soil and in significantly greater plant phosphorus content relative to the nontreated control. Seed yield and available phosphorus in natural soil were significantly greater with a synthetic chemical fertilizer treatment, reduced in phosphorus content, than the biological fertilizer treatment, but a treatment containing the biological fertilizer combined with the synthetic fertilizer provided the significantly greatest seed yield, available phosphorus in natural soil, and plant phosphorus content. These results suggest that the biological fertilizer was capable of improving oilseed rape seed yield, at least in part, through the phosphorus-solubilizing activity of B. megaterium A6.

Gendered Divisions of Fertility Work: Socioeconomic Predictors of Female versus Male Sterilization

ERIC Educational Resources Information Center

Bertotti, Andrea M.

2013-01-01

Domestic labor researchers have examined a multitude of duties disproportionately performed by women, yet the responsibility associated with navigating a couple's fertility--fertility work--has been overlooked. Using data from the 2006-2010 National Survey of Family Growth ("N" = 1,415), the author examined how racial and socioeconomic…

Understanding U.S. fertility: continuity and change in the National Survey of Family Growth, 1988-1995.

PubMed

Mosher, W D; Bachrach, C A

1996-01-01

About 50 studies based on the 1988 National Survey of Family Growth (NSFG) and a telephone reinterview conducted with the same women two years later provide continuing information about the fertility and health of American women. Among the findings of these studies are that black women have almost twice as many pregnancies as do white women (5.1 vs. 2.8), with nearly all of the difference being unintended pregnancies. Unwanted births increased between 1982 and 1988, particularly among less-educated, poor and minority women. This increase in the proportion of unwanted births may have prompted the increase in female sterilization among these groups. Concern with the AIDS epidemic led to increases in condom use between 1982 and 1990, especially among the partners of teenagers and college-educated women. Rates of teenage pregnancy were fairly stable during the period 1980-1988, as increases in the proportion of teenagers having intercourse were offset by increases in condom use. Rates of infertility did not change significantly in the 1980s, but because of delayed childbearing and the aging of the baby-boom cohort, the number of older childless women increased substantially. The 1995 NSFG was redesigned in a number of ways in order to answer a new generation of questions about fertility and women's health in the United States.

Tracking the development of the petaloid fertile stamen in Canna indica: insights into the origin of androecial petaloidy in the Zingiberales

PubMed Central

Almeida, Ana M. R.; Brown, Andrew; Specht, Chelsea D.

2013-01-01

Flowers of the order Zingiberales demonstrate a remarkable trend of reduction in the number of fertile stamens; from five or six fertile, filamentous stamens bearing two thecae each in Musaceae and Strelitziaceae to just a single petaloid stamen bearing a single theca in Cannaceae and Marantaceae. As one progresses from ancestral to derived floral forms, 5–6 fertile stamens are replaced by 4–5 petaloid staminodes. In Cannaceae and Costaceae, all members of the androecial whorls exhibit petaloidy, including the fertile stamen. In Costaceae, a single fertile stamen develops two thecae embedded on a broad petaloid appendage, while in Cannaceae the single fertile stamen is further reduced to a single theca with a prominent, expanded petaloid appendage. Whether petaloidy of the fertile stamen is a synapomorphy of the entire ginger clade (including Cannaceae, Costaceae, Zingiberaceae and Marantaceae), or the result of independent convergent evolution in Cannaceae, Costaceae, and some Zingiberaceae, is unclear. We combine a developmental series of the formation of the petaloid fertile stamen in Canna indica with data on the expression of B- and C-class floral organ identity genes to elucidate the organogenetic identity of the petaloid stamen and staminodes. Our data indicate that the single fertile theca in C. indica and its petaloid appendage are derived from one-half of the primordium of a single stamen, with no contribution from the remaining part of the stamen (i.e. the second theca primordium) which aborts early in development. The petaloid appendage expands later, and develops from the position of the filament/connective of the developing theca. Floral identity gene expression shows that petal identity genes (i.e. B-class genes) are expressed in all floral organs studied while C-class gene AG-1 is expressed in an increasing gradient from sepals to gynoecium, and AG-2 is expressed in all floral organs except the petals. The canonical model for molecular

Association of suicide rates of elderly persons with fertility rates.

PubMed

Shah, Ajit

2008-04-01

A negative correlation between societal suicide rates and social integration has been reported, but rarely specifically examined for suicide rates of the elderly although suicide rates of elderly persons are among the highest. The associations of suicide rates of elderly persons and fertility rates for 81 countries were examined using data from the World Health Organisation and United Nations. Fertility rates were considered a proxy measure for social integration. Multiple regression analysis indicated that suicide rates for males and females in the age bands 65-74 years and 75+ years were independently (negative) correlated with fertility rates. Fertility rates, as a measure of social integration, may interact with, modify and mediate the effect of cultural factors on suicide rates of elderly persons.

Fertility patterns according to occupational grouping in Norway, 1989.

PubMed

Strand, K; Wergeland, E; Bjerkedal, T

1996-03-01

In the early 1990s, most pregnant women in Norway were in gainful employment. This led to increased interest in the possible consequences for reproductive health, and a growing concern for the need to accommodate the pregnancy. We have therefore investigated how accurately general fertility rates predict the number of pregnancies in the workforce. Fertility rates (FR) among employed women and standardized fertility ratios (SFR) in occupational groups were estimated on the basis of information from the Labour Market Statistics and the national survey "Pregnancy and Work", Norway, 1989. The fertility rate among employed women was 17% higher than the general fertility rate. Two occupational groups had significantly different SFRs: technical/professional workers (SFR 118) and transport/communication workers (SFR 82). In addition, differences were found for parity-specific SFRs in administrative/executive work (SFR nullipara 80, SFR para 125) and service work (SFR nullipara 114, SFR para 80). We suggest that work status and occupation should be included among the variables registered in the Medical Birth Registry of Norway, in order to facilitate routine presentations of fertility rates and pregnancy outcomes for women in paid work. The results further indicate that work-specific conditions influence first-birth fertility. This should be explored in demographic studies of the relation between women's fertility and participation in paid work.

[Development and evaluation of fertilizers cemented and coated with organic-inorganic materials].

PubMed

Xiao, Qiang; Wang, Jia-Chen; Zuo, Qiang; Zhang, Lin; Liu, Bao-Cun; Zhao, Tong-Ke; Zou, Guo-Yuan; Xu, Qiu-Ming

2010-01-01

Four kinds of organic-inorganic cementing and coating materials were prepared by a coating method using water as the solvent, and the corresponding cemented and coated fertilizers (B2, PS, F2, and F2F) were produced by disc pelletizer. The tests on the properties of these fertilizers showed that the granulation rate, compression strength, and film-forming rate were B2 > PS > F2 > F2F. Soil column leaching experiment showed that the curve of accumulated nitrogen-dissolving rate was the gentlest for B2. In 48 days, the accumulated nitrogen-dissolving rate was in the order of B2, 54.65% < PS, 56.16% < F2, 59.47%, < F2F, 63.12%. Field experiment showed that compared with the same application amount of NPK, all the test fertilizers had better effects on corn yield, among which, B2 was the best, with the corn yield and fertilizer use efficiency increased by 19.72% and 20.30%, respectively. The yield-increasing effect of other test fertilizers was in the order of PS > F2 > F2F.

The Evolution of Fertility Expectations over the Life Course

PubMed Central

HAYFORD, SARAH R.

2009-01-01

In low-fertility contexts, how many children people have is largely a product of how many children they want. However, the social, institutional, and individual factors that influence how many children people want are not well understood. In particular, there is scant evidence about how fertility expectations change over the life course. This article provides an empirical description of changes in women’s expected fertility over the entire span of childbearing years. Using data from the National Longitudinal Survey of Youth, 1979 cohort, group-based trajectory analysis illuminates common patterns in the evolution of fertility intentions and identifies individual characteristics associated with these patterns. Factors related to family formation, such as marriage and whether a woman has a child at an early age, are found to be the most consistent correlates of patterns of change in expected family size. PMID:20084828

The relationship between HIV and fertility in the era of antiretroviral therapy in sub-Saharan Africa: evidence from 49 Demographic and Health Surveys.

PubMed

Marston, M; Zaba, B; Eaton, J W

2017-12-01

To describe regional differences in the relative fertility of HIV-positive vs. HIV-negative women and changes as antiretroviral treatment (ART) is scaled up, to improve estimates of predicted need for and coverage of prevention of mother-to-child transmission services at national and subnational levels. We analysed 49 nationally representative household surveys in sub-Saharan Africa between 2003 and 2016 to estimate fertility rate ratios of HIV-positive and HIV-negative women by age using exponential regression and test for regional and urban/rural differences. We estimated the association between national ART coverage and the relationship between HIV and fertility. Significant regional differences exist in HIV and fertility relationships, with less HIV-associated subfertility in Southern Africa. Age patterns of relative fertility are similar. HIV impact on fertility is weaker in urban than rural areas. For women below age 30, regional and urban/rural differences are largely explained by differences in age at sexual debut. Higher levels of national ART coverage were associated with slight attenuation of the relationship between HIV and fertility. Regional differences in HIV-associated subfertility and urban-rural differences in age patterns of relative fertility should be accounted for when predicting need for and coverage of PMTCT services at national and subnational level. Although HIV impacts on fertility are somewhat reduced at higher levels of national ART coverage, differences in fertility between HIV positive and negative remain, and fertility of women on ART should not be assumed to be the same as HIV-negative women. There were few data in recent years, when ART has reached high levels, and this relationship should continue to be assessed as further evidence becomes available. © 2017 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Does a surgical career affect a woman's childbearing and fertility? A report on pregnancy and fertility trends among female surgeons.

PubMed

Phillips, Elizabeth A; Nimeh, Tony; Braga, Julie; Lerner, Lori B

2014-11-01

Increases in pregnancy complication rates and use of assisted reproductive technology (ART) have been demonstrated in female urologists and orthopaedic surgeons when compared with the general US population. To determine if childbearing differences exist across specialties, we evaluated female surgeons in all fields, particularly with regard to fertility. An anonymous, 199-item survey was distributed via specialty female surgeon interest groups and word of mouth to general surgery, gynecology, neurosurgery, ophthalmology, orthopaedics, otolaryngology, plastic surgery, podiatry, and urology. The 1,021 responses were analyzed and compared with Centers for Disease Control National Survey for Family Growth and National Institute of Health data to identify differences between populations. Of women surgeons, 32% reported fertility difficulty; 84% of whom underwent infertility workup. Seventy-six percent of these women used ART to attempt pregnancy. In comparison, only 10.9% of women in the general US population report infertility, and 11% seek infertility services. Of all babies born to female surgeons, at least 13% were conceived using ART. Surgeons had 1.4 biological children, less than the national average. Age at first pregnancy was 33 years, compared with a national average of 23. If ART was implemented, surgeon age at first birth increased to 35.4 years. Highest rates of infertility existed in otolaryngology (29%), general surgery (22%), and orthopaedics (18%). Female surgeons have first pregnancies later in life, fewer children, and report more issues with infertility. Assisted reproductive technology is implemented more often by female surgeons than the general population. Differences in fertility exist between specialties and warrant additional study. Copyright © 2014 American College of Surgeons. All rights reserved.

Different Places, Different Stories: A Study of Spatial Heterogeneity of County-Level Fertility in China

PubMed Central

Wang, Donghui; Chi, Guangqing

2018-01-01

Background China has been characterized by persistently low fertility rates since the 1990s. Existing literature has examined the relationships of fertility levels with social, economic, and policy-related determinants. However, the possible spatial variations in these relationships have not been investigated. Objective The purpose of this study is to examine the potential spatially varying relationships between county-level fertility rates and policy and socioeconomic factors in China. Methods Using geocoded 2010 county-level census data, this study adopts the geographically weighted regression (GWR) method to identify place-specific relationships between county-level total fertility rate (TFR) and socioeconomics and policy-related factors. Conclusions We find relationships between TFR and widely used social, economic, and policy-related factors (rural Hukou, ethnic minority, female education, net migration rate, poor living standard, sex ratio at birth, and fertility policy compliance ratio) vary spatially in terms of the direction, strength, and magnitude. The spatial variation is largely due to the difference in local characteristics. The differences and the complexities of localities cannot be told by a single story of either government intervention or socioeconomic development. Contribution This study extends the existing fertility research in China by explicitly recognizing the spatial heterogeneity in the impacts of policy and socioeconomic factors on the local fertility rate. This study sets the stage for future research that will contextually analyze varying fertility rates at the sub-national level in China and other countries. PMID:29593449

Development of a Stereovision-Based Technique to Measure the Spread Patterns of Granular Fertilizer Spreaders

PubMed Central

Cool, Simon R.; Pieters, Jan G.; Seatovic, Dejan; Mertens, Koen C.; Nuyttens, David; Van De Gucht, Tim C.; Vangeyte, Jürgen

2017-01-01

Centrifugal fertilizer spreaders are by far the most commonly used granular fertilizer spreader type in Europe. Their spread pattern however is error-prone, potentially leading to an undesired distribution of particles in the field and losses out of the field, which is often caused by poor calibration of the spreader for the specific fertilizer used. Due to the large environmental impact of fertilizer use, it is important to optimize the spreading process and minimize these errors. Spreader calibrations can be performed by using collection trays to determine the (field) spread pattern, but this is very time-consuming and expensive for the farmer and hence not common practice. Therefore, we developed an innovative multi-camera system to predict the spread pattern in a fast and accurate way, independent of the spreader configuration. Using high-speed stereovision, ejection parameters of particles leaving the spreader vanes were determined relative to a coordinate system associated with the spreader. The landing positions and subsequent spread patterns were determined using a ballistic model incorporating the effect of tractor motion and wind. Experiments were conducted with a commercial spreader and showed a high repeatability. The results were transformed to one spatial dimension to enable comparison with transverse spread patterns determined in the field and showed similar results. PMID:28617339

The Impact of Family Policy Expenditure on Fertility in Western Europe

PubMed Central

KALWIJ, ADRIAAN

2010-01-01

This article analyzes the impact on fertility of changes in national expenditure for family allowances, maternity- and parental-leave benefits, and childcare subsidies. To do so, I estimate a model for the timing of births using individual-level data from 16 western European countries, supplemented with data on national social expenditure for different family policy programs. The latter allow approximation of the subsidies that households with children receive from such programs. The results show that increased expenditure on family policy programs that help women to combine family and employment— and thus reduce the opportunity cost of children—generates positive fertility responses. PMID:20608108

Accelerating development with fertilization in a young natural Piedmont mixed hardwood pine stand

Treesearch

B. J. Berenguer; M. H. Gocke; J. L. Schuler; E. Treasure; D. J. Robison

2010-01-01

A rising two-year-old even-aged naturally regenerated upland Piedmont mixed hardwood-pine stand was broadcast fertilized with N, N + P, and N + P + K to evaluate stand level responses to fertility treatments. There were significant positive stand responses in self thinning and mean stem size measured two growing seasons after fertilizer applications. Findings suggest...

The impact of cross-border reproductive care or 'fertility tourism' on NHS maternity services.

PubMed

McKelvey, A; David, A L; Shenfield, F; Jauniaux, E R

2009-10-01

High order multiple pregnancies have substantial morbidity and mortality. Fertility treatment is commonly responsible for their conception and is available globally with variable regulation. We investigated cross-border fertility treatment in these pregnancies in a UK fetal medicine unit, recording mode of conception, country of fertility treatment, reason for non-UK treatment and fetal reduction. Over an 11-year period, 109 women had a high order multiple pregnancy. Ninety-four women (86%) conceived with fertility treatment of whom 24 (26%) had this performed overseas. Cross-border fertility treatment poses an increasing challenge to obstetricians. National data on its occurrence is urgently needed.

The Pathways fertility preservation decision aid website for women with cancer: development and field testing.

PubMed

Woodard, Terri L; Hoffman, Aubri S; Covarrubias, Laura A; Holman, Deborah; Schover, Leslie; Bradford, Andrea; Hoffman, Derek B; Mathur, Aakrati; Thomas, Jerah; Volk, Robert J

2018-02-01

To improve survivors' awareness and knowledge of fertility preservation counseling and treatment options, this study engaged survivors and providers to design, develop, and field-test Pathways: a fertility preservation patient decision aid website for young women with cancer©. Using an adapted user-centered design process, our stakeholder advisory group and research team designed and optimized the Pathways patient decision aid website through four iterative cycles of review and revision with clinicians (n = 21) and survivors (n = 14). Field-testing (n = 20 survivors) assessed post-decision aid scores on the Fertility Preservation Knowledge Scale, feasibility of assessing women's decision-making values while using the website, and website usability/acceptability ratings. Iterative stakeholder engagement optimized the Pathways decision aid website to meet survivors' and providers' needs, including providing patient-friendly information and novel features such as interactive value clarification exercises, testimonials that model shared decision making, financial/referral resources, and a printable personal summary. Survivors scored an average of 8.2 out of 13 (SD 1.6) on the Fertility Preservation Knowledge Scale. They rated genetic screening and having a biological child as strong factors in their decision-making, and 71% indicated a preference for egg freezing. Most women (> 85%) rated Pathways favorably, and all women (100%) said they would recommend it to other women. The Pathways decision aid is a usable and acceptable tool to help women learn about fertility preservation. The Pathways decision aid may help women make well-informed values-based decisions and prevent future infertility-related distress.

Fertility Preservation for Pediatric Patients: Current State and Future Possibilities.

PubMed

Johnson, Emilie K; Finlayson, Courtney; Rowell, Erin E; Gosiengfiao, Yasmin; Pavone, Mary Ellen; Lockart, Barbara; Orwig, Kyle E; Brannigan, Robert E; Woodruff, Teresa K

2017-07-01

This review provides an overview of pediatric fertility preservation. Topics covered include the patient populations who could benefit, the current state of fertility preservation options and research, and considerations related to ethics and program development. A broad Embase® and PubMed® search was performed to identify publications discussing investigational, clinical, ethical and health care delivery issues related to pediatric fertility preservation. Relevant publications were reviewed and summarized. Populations who could benefit from fertility preservation in childhood/adolescence include oncology patients, patients with nononcologic conditions requiring gonadotoxic chemotherapy, patients with differences/disorders of sex development and transgender individuals. Peripubertal and postpubertal fertility preservation options are well established and include cryopreservation of oocytes, embryos or sperm. Prepubertal fertility preservation is experimental. Multiple lines of active research aim to develop technologies that will enable immature eggs and sperm to be matured and used to produce a biological child in the future. Ethical challenges include the need for parental proxy decision making and the fact that fertility preservation procedures can be considered not medically necessary. Successful multidisciplinary fertility preservation care teams emphasize partnerships with adult colleagues, prioritize timely consultations and use standardized referral processes. Some aspects of fertility preservation are not covered by insurance and out-of-pocket costs can be prohibitive. Pediatric fertility preservation is an emerging, evolving field. Fertility preservation options for prepubertal patients with fertility altering conditions such as cancer and differences/disorders of sex development are currently limited. However, multiple lines of active research hold promise for the future. Key considerations include establishing a multidisciplinary team to provide

Abiotic processes are insufficient for fertile island development: A 10-year artificial shrub experiment in a desert grassland

NASA Astrophysics Data System (ADS)

Li, Junran; Gilhooly, William P.; Okin, Gregory S.; Blackwell, John

2017-03-01

The relative importance of biotic and abiotic processes in the development of "fertile islands" in dryland systems has rarely been investigated. Here we approached this question by using artificial shrubs, which exclude plant litter production and soil nutrient uptake, but retain the functions of trapping windblown material, funneling of stemflow, and differential rain splash. We conducted a vegetation manipulation study more than a decade ago in the desert grassland of southern New Mexico and subsequently revisited the site in 2012 and 2015. The results show that no notable soil mounds were observed under the artificial shrubs; however, soil texture under the artificial shrubs has gradually changed to resemble the patterns of soil particle-size distribution under natural shrubs. Our results highlight that with the exclusion of direct biotic additions, soils captured by shrub canopies are not necessarily fertile and thus do not themselves contribute to the development of fertile islands.

SOCIAL DETERMINANTS OF LOW FERTILITY IN BRAZIL.

PubMed

Castanheira, Helena Cruz; Kohler, Hans-Peter

2017-11-01

An increasing number of developing countries are experiencing below replacement fertility rates. Although the factors associated with low fertility in developed countries have been widely explored in the literature, studies of low fertility in middle- and low-income countries continue to be rare. To help fill this gap, Brazil was used as a case study to assess whether human development, gender equality and the ability of mothers with young children to work are associated with the likelihood of married or cohabiting women to have a child. For this purpose, multilevel logistic regressions were estimated using the 1991, 2000 and 2010 Brazilian Demographic Censuses. It was found that human development was negatively associated with fertility in the three periods analysed. Gender equality and the ability of mothers with young children to work were positively associated with the odds of having higher order births in Brazil in 2000 and 2010. In 1991, these variables were not associated with higher order births, and gender equality was negatively associated with first births. The positive association found in 2000 and 2010 may constitute a reversal of the relationship that in all likelihood prevailed earlier in the demographic transition when gender equality was most likely negatively correlated with fertility levels.

The South African fertility decline: Evidence from two censuses and a Demographic and Health Survey.

PubMed

Moultrie, Tom A; Timaeus, Ian M

2003-11-01

Inadequate data and apartheid policies have meant that, until recently, most demographers have not had the opportunity to investigate the level of, and trend in, the fertility of South African women. The 1996 South Africa Census and the 1998 Demographic and Health Survey provide the first widely available and nationally representative demographic data on South Africa since 1970. Using these data, this paper describes the South African fertility decline from 1955 to 1996. Having identified and adjusted for several errors in the 1996 Census data, the paper argues that total fertility at that time was 3.2 children per woman nationally, and 3.5 children per woman for African South Africans. These levels are lower than in any other sub-Saharan African country. We show also that fertility in South Africa has been falling since the 1960s. Thus, fertility transition predates the establishment of a family planning programme in the country in 1974.

Reconstruction of spatially detailed global map of NH4+ and NO3- application in synthetic nitrogen fertilizer

NASA Astrophysics Data System (ADS)

Nishina, Kazuya; Ito, Akihiko; Hanasaki, Naota; Hayashi, Seiji

2017-02-01

Currently, available historical global N fertilizer map as an input data to global biogeochemical model is still limited and existing maps were not considered NH4+ and NO3- in the fertilizer application rates. This paper provides a method for constructing a new historical global nitrogen fertilizer application map (0.5° × 0.5° resolution) for the period 1961-2010 based on country-specific information from Food and Agriculture Organization statistics (FAOSTAT) and various global datasets. This new map incorporates the fraction of NH4+ (and NO3-) in N fertilizer inputs by utilizing fertilizer species information in FAOSTAT, in which species can be categorized as NH4+- and/or NO3--forming N fertilizers. During data processing, we applied a statistical data imputation method for the missing data (19 % of national N fertilizer consumption) in FAOSTAT. The multiple imputation method enabled us to fill gaps in the time-series data using plausible values using covariates information (year, population, GDP, and crop area). After the imputation, we downscaled the national consumption data to a gridded cropland map. Also, we applied the multiple imputation method to the available chemical fertilizer species consumption, allowing for the estimation of the NH4+ / NO3- ratio in national fertilizer consumption. In this study, the synthetic N fertilizer inputs in 2000 showed a general consistency with the existing N fertilizer map (Potter et al., 2010) in relation to the ranges of N fertilizer inputs. Globally, the estimated N fertilizer inputs based on the sum of filled data increased from 15 to 110 Tg-N during 1961-2010. On the other hand, the global NO3- input started to decline after the late 1980s and the fraction of NO3- in global N fertilizer decreased consistently from 35 to 13 % over a 50-year period. NH4+-forming fertilizers are dominant in most countries; however, the NH4+ / NO3- ratio in N fertilizer inputs shows clear differences temporally and geographically. This

The intimate genetics of Drosophila fertilization

PubMed Central

Loppin, Benjamin; Dubruille, Raphaëlle; Horard, Béatrice

2015-01-01

The union of haploid gametes at fertilization initiates the formation of the diploid zygote in sexually reproducing animals. This founding event of embryogenesis includes several fascinating cellular and nuclear processes, such as sperm–egg cellular interactions, sperm chromatin remodelling, centrosome formation or pronuclear migration. In comparison with other aspects of development, the exploration of animal fertilization at the functional level has remained so far relatively limited, even in classical model organisms. Here, we have reviewed our current knowledge of fertilization in Drosophila melanogaster, with a special emphasis on the genes involved in the complex transformation of the fertilizing sperm nucleus into a replicated set of paternal chromosomes. PMID:26246493

[Present situation and prospects of special fertilizer for traditional Chinese medicine herbs].

PubMed

Yan, Zhang; Liu, Yong; Wang, Ji-Yong; Wang, Wen-Quan

2004-08-01

To find out the present situation and the development trend special fertilizer of the traditional Chinese medicina plants. By consulting a great deal of literatures on special fertilizer and fertilization on traditional Chinese medicine herbs, and based on the scientific research and manufacture experience of the author, and the theoretic actuality of the researches on the fertilization of traditional Chinese medicine herbs, the present study of the special fertilizer inside and outside of our country was analyzed. The view points of developing special fertilizer for Chinese traditional medicine were put forward, and the development trend of special fertilizer for traditional Chinese medicine herbs was forecasted.

[Development of a new type of biological organic fertilizer and its effect on the growth promotion of tomato].

PubMed

Liu, Qiu Mei; Chen, Xing; Meng, Xiao Hui; Ye, Qi; Li, Tuo; Liu, Dong Yang; Shen, Qi Rong

2017-10-01

The objective of this study was to improve the ability of sporulation production of Trichoderma guizhouense NJAU4742 under solid state fermentation by using rice straw and amino acids as resources, and the fermentation products were used as inoculants of the organic fertilizers adding with different ratios of amino acids solution to develop a new type of biological organic fertilizer. The results indicated that the optimal condition for sporulation by T. guizhouense NJAU4742 was soaking in 30 times diluted amino acid solution for one whole night, with initial pH 3.5, 75% of moisture content and 30% of corn powder, under which the sporulation reached to 2.40×10 10 CFU·g -1 . The fermentation products were inoculated at 2% into the mature organic fertilizer containing 20% of amino acids solution, and the sporulation and IAA content were 6.40×10 9 CFU·g -1 and 38.66 mg·kg -1 , which were 1142.30 and 1.42 times higher than that of CK after 7 days, respectively. Pot experiment showed that biological organic fertilizer could significantly promote the growth of tomato, and the height of the tomato increased by 98.8% and 23.8%, respectively, compared with CK. The stem diameters of AT (amino acids + mature organic fertilizer + T. guizhouense NJAU4742) and AA (amino acids + mature organic fertilizer) were increased by 58.9% and 10.3%, respectively, compared with CK. As for the chlorophyll, leaf length and leaf width, the values also increased significantly. The highest spore content was obtained by using amino acids and rice straw as substrates under solid state fermentation (SSF), which overcame the difficulties of producing new type of biological organic fertilizer during the large scale industrial production. Biological organic fertilizer and amino acids organic fertilizer could significantly promote the growth of tomato compared with the chemical fertilizer, and had a good application prospect in intensive agriculture.

Fertility comparison between wild type and transgenic mice by in vitro fertilization.

PubMed

Vasudevan, Kuzhalini; Raber, James; Sztein, Jorge

2010-08-01

Transgenic mice are increasingly used as animal models for studies of gene function and regulation of mammalian genes. Although there has been continuous and remarkable progress in the development of transgenic technology over several decades, many aspects of the resulting transgenic model's phenotype cannot be completely predicted. For example, it is well known that as a consequence of the random insertion of the injected DNA construct, several founder mice of the new line need to be analyzed for possible differences in phenotype secondary to different insertion sites. The Knock out technique for transgenic production disrupts a specific gene by insertion or homologous recombination creating a null expression or replacement of the gene with a marker to localize it expression. This modification could result in pleiotropic phenotype if the gene is also expressed in tissues other than the target organs. Although the future breeding performance of the newly created model is critical to many studies, it is rarely anticipated that the new integrations could modify the reproductive profile of the new transgenic line. To date, few studies have demonstrated the difference between the parent strain's reproductive performance and the newly developed transgenic model. This study was designed to determine whether a genetic modification, knock out (KO) or transgenics, not anticipated to affect reproductive performance could affect the resulting reproductive profile of the newly developed transgenic mouse. More specifically, this study is designed to study the impact of the genetic modification on the ability of gametes to be fertilized in vitro. We analyzed the reproductive performance of mice with different background strains: FVB/N, C57BL/6 (129Sv/J x C57Bl/6)F1 and outbred CD1((R)) and compared them to mice of the same strain carrying a transgene or KO which was not anticipated to affect fertility. In vitro Fertilization was used to analyze the fertility of the mice. Oocytes

[Variation characteristics of maize yield and fertilizer utilization rate on an upland yellow soil under long term fertilization].

PubMed

Luo, Long-Zao; Li, Yu; Zhang, Wen-An; Xiao, Hou-Jun; Jiang, Tai-Ming

2013-10-01

An analysis was made on the 16-year experimental data from the long term fertilization, experiment of maize on a yellow soil in Guizhou of Southwest China. Four treatments, i. e. , no fertilization (CK), chemical fertilization (165 kg N x hm(-2), 82.5 kg P2O5 x hm(-2), and 82.5 kg K2O x hm(-2), NPK), organic manure (30555 kg x hm(-2), M), and combined applicatioin of chemical fertilizers and organic manure (NPKM), were selected to analyze the variation trends of maize yield and fertilizer use efficiency on yellow soil under effects of different long term fertilization modes, aimed to provide references for evaluating and establishing long term fertilization mode and promote the sustainable development of crop production. Overall, the maize yield under long term fertilization had an increasing trend, with a large annual variation. Treatment NPKM had the best yield-increasing effect, with the maize yield increased by 4075.71 kg x hm(-2) and the increment being up to 139.2%. Long term fertilization increased the fertilizer utilization efficiency of maize. In treatment M, the nitrogen and phosphorus utilization rates were increased significantly by 35.4% and 18.8%, respectively. Treatment NPK had obvious effect in improving potassium utilization rate, with an increment of 20% and being far higher than that in treatments M (8.7%) and NPKM (9.2%). The results showed that long term fertilization, especially the combined application of chemical fertilizers and organic manure, was of great importance in increasing crop yield and fertilizer use efficiency.

India's needs and priorities in fertility regulation research.

PubMed

Puri, C P

1999-02-01

This article evaluates the needs and priorities of India in fertility regulation research. There are multivariate factors that affect the perceptions of people about fertility regulation in India. The socioeconomic status, level of education and religious beliefs have strong influences on their decision on the family size, spacing between children and also the sex of the children. Moreover, a large number of people are either quite ignorant of or cannot afford to avail with the technologies and services for controlling their fertility. These factors generally perpetuate high fertility, which strongly affect the infant and maternal mortality, and eventually the quality of life both for the present and the future generation. The International Conference on Population and Development Program of Action has provided India with an alternative to develop newer methods of fertility regulation so as to widen contraceptive choices. The objective of research in fertility regulation should ensure the fertility control of couples and ability to plan the number and spacing of children. Research in fertility regulation should be aimed at expanding contraceptive choices by improving the accessibility and acceptability of good quality contraceptive products and services. It would necessitate: improving the quality of care; increasing awareness about sexuality and fertility regulation; empowering women; and increasing male-female partnership in sharing responsibilities for family planning and parenthood.

Demand impact and policy implications from taxing nitrogen fertilizer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foltz, J.C.

1992-12-01

Recent concern has focused on nitrogen fertilizer as a potential contaminant of groundwater. A demand function for fertilizer was developed using the quantity of fertilizer purchased, corn yield, real price of nitrogen fertilizer, lagged fertilizer purchases, a land value variable and the real price of corn as explanatory variables. Short and long-run price elasticities of demand were estimated to be inelastic. Support was found for the hypothesis that demand for nitrogen fertilizer has become more price inelastic over time. From a policy standpoint, a tax on nitrogen fertilizer may not be the most effective method to reduce consumption.

Observational study of the development and evaluation of a fertility preservation patient decision aid for teenage and adult women diagnosed with cancer: the Cancer, Fertility and Me research protocol

PubMed Central

Jones, G L; Hughes, J; Mahmoodi, N; Greenfield, D; Brauten-Smith, G; Skull, J; Gath, J; Yeomanson, D; Baskind, E; Snowden, J A; Velikova, G; Collins, K; Stark, D; Phillips, R; Lane, S; Bekker, H L

2017-01-01

Introduction Women diagnosed with cancer and facing potentially sterilising cancer treatment have to make time-pressured decisions regarding fertility preservation with specialist fertility services while undergoing treatment of their cancer with oncology services. Oncologists identify a need for resources enabling them to support women's fertility preservation decisions more effectively; women report wanting more specialist information to make these decisions. The overall aim of the ‘Cancer, Fertility and Me’ study is to develop and evaluate a new evidence-based patient decision aid (PtDA) for women with any cancer considering fertility preservation to address this unmet need. Methods and analysis This is a prospective mixed-method observational study including women of reproductive age (16 years +) with a new diagnosis of any cancer across two regional cancer and fertility centres in Yorkshire, UK. The research involves three stages. In stage 1, the aim is to develop the PtDA using a systematic method of evidence synthesis and multidisciplinary expert review of current clinical practice and patient information. In stage 2, the aim is to assess the face validity of the PtDA. Feedback on its content and format will be ascertained using questionnaires and interviews with patients, user groups and key stakeholders. Finally, in stage 3 the acceptability of using this resource when integrated into usual cancer care pathways at the point of cancer diagnosis and treatment planning will be evaluated. This will involve a quantitative and qualitative evaluation of the PtDA in clinical practice. Measures chosen include using count data of the PtDAs administered in clinics and accessed online, decisional and patient-reported outcome measures and qualitative feedback. Quantitative data will be analysed using descriptive statistics, paired sample t-tests and CIs; interviews will be analysed using thematic analysis. Ethics and dissemination Research Ethics Committee

Observational study of the development and evaluation of a fertility preservation patient decision aid for teenage and adult women diagnosed with cancer: the Cancer, Fertility and Me research protocol.

PubMed

Jones, G L; Hughes, J; Mahmoodi, N; Greenfield, D; Brauten-Smith, G; Skull, J; Gath, J; Yeomanson, D; Baskind, E; Snowden, J A; Jacques, R M; Velikova, G; Collins, K; Stark, D; Phillips, R; Lane, S; Bekker, H L

2017-03-13

Women diagnosed with cancer and facing potentially sterilising cancer treatment have to make time-pressured decisions regarding fertility preservation with specialist fertility services while undergoing treatment of their cancer with oncology services. Oncologists identify a need for resources enabling them to support women's fertility preservation decisions more effectively; women report wanting more specialist information to make these decisions. The overall aim of the 'Cancer, Fertility and Me' study is to develop and evaluate a new evidence-based patient decision aid (PtDA) for women with any cancer considering fertility preservation to address this unmet need. This is a prospective mixed-method observational study including women of reproductive age (16 years +) with a new diagnosis of any cancer across two regional cancer and fertility centres in Yorkshire, UK. The research involves three stages. In stage 1, the aim is to develop the PtDA using a systematic method of evidence synthesis and multidisciplinary expert review of current clinical practice and patient information. In stage 2, the aim is to assess the face validity of the PtDA. Feedback on its content and format will be ascertained using questionnaires and interviews with patients, user groups and key stakeholders. Finally, in stage 3 the acceptability of using this resource when integrated into usual cancer care pathways at the point of cancer diagnosis and treatment planning will be evaluated. This will involve a quantitative and qualitative evaluation of the PtDA in clinical practice. Measures chosen include using count data of the PtDAs administered in clinics and accessed online, decisional and patient-reported outcome measures and qualitative feedback. Quantitative data will be analysed using descriptive statistics, paired sample t-tests and CIs; interviews will be analysed using thematic analysis. Research Ethics Committee approval (Ref: 16/EM/0122) and Health Research Authority approval

Potential substitution of mineral P fertilizer by manure: EPIC development and implementation

NASA Astrophysics Data System (ADS)

Azevedo, Ligia B.; Vadas, Peter A.; Balkovič, Juraj; Skalský, Rastislav; Folberth, Christian; van der Velde, Marijn; Obersteiner, Michael

2016-04-01

Sources of mineral phosphorus (P) fertilizers are non-renewable. Although the longevity of P mines and the risk of future P depletion are highly debated P scarcity may be detrimental to agriculture in various ways. Some of these impacts include increasing food insecurity and nitrogen (N) and P imbalances, serious fluctuations in the global fertilizer and crop market prices, and contribution in geopolitical conflicts. P-rich waste produced from livestock production activities (i.e. manure) are an alternative to mineral P fertilizer. The substitution of mineral fertilizer with manure (1) delays the depletion of phosphate rock stocks, (2) reduces the vulnerability of P fertilizer importing countries to sudden changes in the fertilizer market, (3) reduces the chances of geopolitical conflicts arising from P exploitation pressures, (4) avoids the need for environmental protection policies in livestock systems, (5) is an opportunity for the boosting of crop yields in low nutrient input agricultural systems, and (6) contributes to the inflow of not only P but also other essential nutrients to agricultural soils. The Environmental Policy Integrated Climate model (EPIC) is a widely used process-based, crop model integrating various environmental flows relevant to crop production as well as environmental quality assessments. We simulate crop yields using a powerful computer cluster infra-structure (known as EPIC-IIASA) in combination with spatially-explicit EPIC input data on climate, management, soils, and landscape. EPIC-IIASA contains over 131,000 simulation units and it has 5 arc-min resolution. In this work, we implement two process-based models of manure biogeochemistry into EPIC-IIASA, i.e. SurPhos (for P) and Manure DNDC (for N and carbon) and a fate model model describing nutrient outflows from fertilizer via runoff. For EGU, we will use EPIC-IIASA to quantify the potential of mineral P fertilizer substitution with manure. Specifically, we will estimate the relative

In Vitro Measures for Assessing Boar Semen Fertility.

PubMed

Jung, M; Rüdiger, K; Schulze, M

2015-07-01

Optimization of artificial insemination (AI) for pig production and evaluation of the fertilizing capacity of boar semen are highly related. Field studies have demonstrated significant variation in semen quality and fertility. The semen quality of boars is primarily affected by breed and season. AI centres routinely examine boar semen to predict male fertility. Overall, the evaluation of classical parameters, such as sperm morphology, sperm motility, sperm concentration and ejaculate volume, allows the identification of ejaculates corresponding to poor fertility but not high-efficiency prediction of field fertility. The development of new sperm tests for measuring certain sperm functions has attempted to solve this problem. Fluorescence staining can categorize live and dead spermatozoa in the ejaculate and identify spermatozoa with active mitochondria. Computer-assisted semen analysis (CASA) provides an objective assessment of multiple kinetic sperm parameters. However, sperm tests usually assess only single factors involved in the fertilization process. Thus, basing prediction of fertilizing capacity on a selective collection of sperm tests leads to greater accuracy than using single tests. In the present brief review, recent diagnostic laboratory methods that directly relate to AI performance as well as the development of a new boar fertility in vitro index are discussed. © 2015 Blackwell Verlag GmbH.

Implementation strategy for achieving replacement level fertility.

PubMed

1993-01-01

The recommendation of the Bali Declaration on Population and Sustainable Development at the ESCAP regional conference was to adopt strategies for attaining replacement-level fertility of 2.1 or 2.2 children by 2010. East Asian countries, except Mongolia and the Democratic People's Republic of Korea, and the Southeast Asian countries Singapore and Thailand have already reached replacement-level fertility. Most larger Oceanic countries have also done so. Only South Asian Sri Lanka and southern India have attained replacement level. The following conditions slow or hinder the goal, but they do not provide an "absolute" barrier to fertility decline: social welfare schemes and old age security, son preference, lack of government family planning, poverty, relatively high mortality, low status of women, and education status. Theories of demographic transition have postulated that economic and social development initially brings a decline in mortality, and later brings a decline in fertility; and high fertility was an adaptation to high mortality. Policy gets caught in the lag between mortality and fertility decline. Eventually the cultural motives for high fertility are undercut by social and economic development. Although the generalization that economic growth slows fertility is true for South Asia, the correlation is uneven. Forceful government-sponsored family planning programs in Bangladesh and China may lead the way to strategies for decline in ESCAP region. A Thailand study suggested important factors were fundamental social change, the increased cost of children, cultural acceptance of birth control, a latent demand for fertility control, and government efforts in family planning. ESCAP countries have in common relatively high morality and inadequate public health programs, patriarchal structures, and limited female autonomy, poverty and landlessness, lack of community cohesiveness, and inadequate family planning programs. Weaknesses in programs are attributed to

Proximate determinants of fertility in peninsular Malaysia.

PubMed

Tey, Nai Peng; Ng, Sor Tho; Yew, Siew Yong

2012-05-01

The continuing decline in fertility despite a contraction in contraceptive use in Peninsular Malaysia since the mid-1980s has triggered considerable interest in the reasons behind this phenomenon, such as increase in abortion, sterility, and out-of-wedlock pregnancy. Fertility decline has been attributed to rapid socioeconomic development, which can only influence fertility through the intermediate variables. Application of vital statistics, population census, and survey data of Peninsular Malaysia on Bongaarts's model vindicates that marriage postponement and contraceptive use are the 2 most important proximate determinants of fertility, but the effects are not uniform across the ethnic groups. For instance, the predicted total fertility rate for Chinese and Malays are 2.9 and 1.6, respectively, compared with the observed level of 3.0 and 1.9. Postpartum infecundability and abortion also play a part in explaining ethnic fertility differentials. The fertility inhibiting effects of these proximate determinants have significant implications on reproductive health and future population growth.

Diffusion and Adoption of Innovations in Fertilizer-Related Agricultural Production Technology in Developing Countries.

ERIC Educational Resources Information Center

Byrnes, Kerry J.

This monograph reviews a wide range of research literature on the diffusion and adoption of innovations in agricultural production technology in the developing countries, with particular emphasis on the practice of using commercially purchased, inorganic fertilizer as a source of plant nutrients. It is intended that the report's documentation of…

Injurious effects of emodin on maturation of mouse oocytes, fertilization and fetal development via apoptosis.

PubMed

Chang, Mei-Hui; Chang, Shao-Chung; Chan, Wen-Hsiung

2012-10-29

Emodin (1,3,8-trihydroxy-6-methylanthraquinone), a major constituent of rhubarb, has a wide range of therapeutic applications. Previous studies have established that emodin induces apoptosis in the inner cell mass and trophectoderm of mouse blastocysts and leads to decreased embryonic development and viability, indicating a role as an injury risk factor for normal embryonic development. However, the mechanisms underlying its hazardous effects have yet to be characterized. In the current study, we further investigated the effects of emodin on oocyte maturation and subsequent pre- and post-implantation development, both in vitro and in vivo. Notably, emodin induced a significant reduction in the rates of oocyte maturation, fertilization, and in vitro embryonic development. Treatment of oocytes with emodin during in vitro maturation (IVM) led to increased resorption of postimplantation embryos and decreased fetal weight. Experiments using an in vivo mouse model disclosed that consumption of drinking water containing 20-40 μM emodin led to decreased oocyte maturation and in vitro fertilization, as well as early embryonic developmental injury. Notably, pretreatment with a caspase-3-specific inhibitor effectively prevented emodin-triggered injury effects, suggesting that impairment of embryo development occurs via a caspase-dependent apoptotic process.

Gene regulation associated with sexual development and female fertility in different isolates of Trichoderma reesei.

PubMed

Dattenböck, Christoph; Tisch, Doris; Schuster, Andre; Monroy, Alberto Alonso; Hinterdobler, Wolfgang; Schmoll, Monika

2018-01-01

Trichoderma reesei is one of the most frequently used filamentous fungi in industry for production of homologous and heterologous proteins. The ability to use sexual crossing in this fungus was discovered several years ago and opens up new perspectives for industrial strain improvement and investigation of gene regulation. Here we investigated the female sterile strain QM6a in comparison to the fertile isolate CBS999.97 and backcrossed derivatives of QM6a, which have regained fertility (FF1 and FF2 strains) in both mating types under conditions of sexual development. We found considerable differences in gene regulation between strains with the CBS999.97 genetic background and the QM6a background. Regulation patterns of QM6a largely clustered with the backcrossed FF1 and FF2 strains. Differential regulation between QM6a and FF1/FF2 as well as clustering of QM6a patterns with those of CBS999.97 strains was also observed. Consistent mating type dependent regulation was limited to mating type genes and those involved in pheromone response, but included also nta1 encoding a putative N-terminal amidase previously not associated with development. Comparison of female sterile QM6a with female fertile strains showed differential expression in genes encoding several transcription factors, metabolic genes and genes involved in secondary metabolism. Evaluation of the functions of genes specifically regulated under conditions of sexual development and of genes with highest levels of transcripts under these conditions indicated a relevance of secondary metabolism for sexual development in T. reesei . Among others, the biosynthetic genes of the recently characterized SOR cluster are in this gene group. However, these genes are not essential for sexual development, but rather have a function in protection and defence against competitors during reproduction.

Development of a health promotion programme to improve awareness of factors that affect fertility, and evaluation of its reach in the first 5 years.

PubMed

Hammarberg, Karin; Norman, Robert J; Robertson, Sarah; McLachlan, Robert; Michelmore, Janet; Johnson, Louise

2017-06-01

Awareness among people of reproductive age about the factors that influence fertility and reproductive outcomes, including medically assisted reproduction outcomes, is generally low. To improve awareness about the potentially modifiable factors that affect fertility and reproductive outcomes, 'Your Fertility', a fertility health promotion programme funded by the Australian Government, was established in 2011. This paper describes the development and evaluation of the reach of the Your Fertility programme from its inception in 2011 to June 2016. Systematically recorded outcomes for the programme's key focus areas and Google Analytics data were collated. Key achievements include developing and maintaining an internationally renowned website that experiences high growth and demand for fertility-related information; by 2016, over 5 million users had viewed more than 10 million webpages, and over 96,000 users had engaged in programme messages across social media. Programme messages have reached more than 4 million Australian social media users, and a potential audience of 150 million through media coverage across more than 320 media features. More than 4200 education and health professionals have completed online learning modules, and external partnerships have been established with 14 separate organizations. Data collected over 5 years indicate that the Your Fertility programme meets a need for targeted, evidence-based, accessible fertility-related information.

Impaired fertility in T-stock female mice after superovulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wyrobek, A J; Bishop, J B; Marchetti, F

2003-12-05

Superovulation of female mice with exogenous gonadotrophins is routinely used for increasing the number of eggs ovulated by each female in reproductive and developmental studies. We report an unusual effect of superovulation on fertilization in mice. In vivo matings of superovulated T-stock females with B6C3F1 males resulted in a 2-fold reduction (P<0.001) in the frequencies of fertilized eggs compared to control B6C3F1 matings. In addition, {approx}22 hr after mating only 15% of fertilized eggs recovered in T-stock females had reached the metaphase stage of the first cleavage division versus 87% in B6C3F1 females (P < 0.0001). Matings with T-stock malesmore » did not improve the reproductive performance of T-stock females. To investigate the possible cause(s) for the impaired fertilization and zygotic development, the experiments were repeated using in vitro fertilization. Under these conditions, the frequencies of fertilized eggs were not different in superovulated T-stock and B6C3F1 females (51.7% {+-} 6.0 and 64.5% {+-}3.8, P=0.10). There was a 7-fold increase in the frequencies of fertilized T-stock eggs that completed the first cell cycle of development after in vitro versus in vivo fertilization. These results rule out an intrinsic deficiency of the T-stock oocyte as the main reason for the impaired fertility after in vivo matings and suggest that superovulation of T-stock females induces a hostile oviductal and uterine environment with dramatic effects on fertilization and zygotic development.« less

Transporters involved in pH and K + homeostasis affect pollen wall formation, male fertility, and embryo development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Padmanaban, Senthilkumar; Czerny, Daniel D.; Levin, Kara A.

Flowering plant genomes encode multiple cation/H + exchangers (CHXs) whose functions are largely unknown. AtCHX17, AtCHX18, and AtCHX19 are membrane transporters that modulate K+ and pH homeostasis and are localized in the dynamic endomembrane system. Loss of function reduced seed set, but the particular phase(s) of reproduction affected was not determined. Pollen tube growth and ovule targeting of chx17chx18chx19 mutant pollen appeared normal, but reciprocal cross experiments indicate a largely male defect. Although triple mutant pollen tubes reach ovules of a wild-type pistil and a synergid cell degenerated, half of those ovules were unfertilized or showed fertilization of the eggmore » or central cell, but not both female gametes. Fertility could be partially compromised by impaired pollen tube and/or sperm function as CHX19 and CHX18 are expressed in the pollen tube and sperm cell, respectively. When fertilization was successful in self-pollinated mutants, early embryo formation was retarded compared with embryos from wild-type ovules receiving mutant pollen. Thus CHX17 and CHX18 proteins may promote embryo development possibly through the endosperm where these genes are expressed. The reticulate pattern of the pollen wall was disorganized in triple mutants, indicating perturbation of wall formation during male gametophyte development. Lastly, as pH and cation homeostasis mediated by AtCHX17 affect membrane trafficking and cargo delivery, these results suggest that male fertility, sperm function, and embryo development are dependent on proper cargo sorting and secretion that remodel cell walls, plasma membranes, and extracellular factors.« less

Transporters involved in pH and K + homeostasis affect pollen wall formation, male fertility, and embryo development

DOE PAGES

Padmanaban, Senthilkumar; Czerny, Daniel D.; Levin, Kara A.; ...

2017-02-23

Flowering plant genomes encode multiple cation/H + exchangers (CHXs) whose functions are largely unknown. AtCHX17, AtCHX18, and AtCHX19 are membrane transporters that modulate K+ and pH homeostasis and are localized in the dynamic endomembrane system. Loss of function reduced seed set, but the particular phase(s) of reproduction affected was not determined. Pollen tube growth and ovule targeting of chx17chx18chx19 mutant pollen appeared normal, but reciprocal cross experiments indicate a largely male defect. Although triple mutant pollen tubes reach ovules of a wild-type pistil and a synergid cell degenerated, half of those ovules were unfertilized or showed fertilization of the eggmore » or central cell, but not both female gametes. Fertility could be partially compromised by impaired pollen tube and/or sperm function as CHX19 and CHX18 are expressed in the pollen tube and sperm cell, respectively. When fertilization was successful in self-pollinated mutants, early embryo formation was retarded compared with embryos from wild-type ovules receiving mutant pollen. Thus CHX17 and CHX18 proteins may promote embryo development possibly through the endosperm where these genes are expressed. The reticulate pattern of the pollen wall was disorganized in triple mutants, indicating perturbation of wall formation during male gametophyte development. Lastly, as pH and cation homeostasis mediated by AtCHX17 affect membrane trafficking and cargo delivery, these results suggest that male fertility, sperm function, and embryo development are dependent on proper cargo sorting and secretion that remodel cell walls, plasma membranes, and extracellular factors.« less

Toward precision medicine for preserving fertility in cancer patients: existing and emerging fertility preservation options for women.

PubMed

Kim, So-Youn; Kim, Seul Ki; Lee, Jung Ryeol; Woodruff, Teresa K

2016-03-01

As the number of young cancer survivors increases, quality of life after cancer treatment is becoming an ever more important consideration. According to a report from the American Cancer Society, approximately 810,170 women were diagnosed with cancer in 2015 in the United States. Among female cancer survivors, 1 in 250 are of reproductive age. Anticancer therapies can result in infertility or sterility and can have long-term negative effects on bone health, cardiovascular health as a result of reproductive endocrine function. Fertility preservation has been identified by many young patients diagnosed with cancer as second only to survival in terms of importance. The development of fertility preservation technologies aims to help patients diagnosed with cancer to preserve or protect their fertility prior to exposure to chemo- or radiation therapy, thus improving their chances of having a family and enhancing their quality of life as a cancer survivor. Currently, sperm, egg, and embryo banking are standard of care for preserving fertility for reproductive-age cancer patients; ovarian tissue cryopreservation is still considered experimental. Adoption and surrogate may also need to be considered. All patients should receive information about the fertility risks associated with their cancer treatment and the fertility preservation options available in a timely manner, whether or not they decide to ultimately pursue fertility preservation. Because of the ever expanding number of options for treating cancer and preserving fertility, there is now an opportunity to take a precision medicine approach to informing patients about the fertility risks associated with their cancer treatment and the fertility preservation options that are available to them.

A small population of hypothalamic neurons govern fertility: the critical role of VAX1 in GnRH neuron development and fertility maintenance.

PubMed

Hoffmann, Hanne M; Mellon, Pamela L

2016-01-01

Fertility depends on the correct maturation and function of approximately 800 gonadotropin-releasing hormone (GnRH) neurons in the brain. GnRH neurons are at the apex of the hypothalamic-pituitary-gonadal axis that regulates fertility. In adulthood, GnRH neurons are scattered throughout the anterior hypothalamic area and project to the median eminence, where GnRH is released into the portal vasculature to stimulate release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary. LH and FSH then regulate gonadal steroidogenesis and gametogenesis. Absence of GnRH neurons or inappropriate GnRH release leads to infertility. Despite the critical role of GnRH neurons in fertility, we still have a limited understanding of the genes responsible for proper GnRH neuron development and function in adulthood. GnRH neurons originate in the olfactory placode then migrate into the brain. Homeodomain transcription factors expressed within GnRH neurons or along their migratory path are candidate genes for inherited infertility. Using a combined in vitro and in vivo approach, we have identified Ventral Anterior Homeobox 1 ( Vax1 ) as a novel homeodomain transcription factor responsible for GnRH neuron maturation and fertility. GnRH neuron counts in Vax1 knock-out embryos revealed Vax1 to be required for the presence of GnRH-expressing cells at embryonic day 17.5 (E17.5), but not at E13.5. To localize the effects of Vax1 on fertility, we generated Vax1 flox mice and crossed them with Gnrh cre mice to specifically delete Vax1 within GnRH neurons. GnRH staining in Vax1 flox/flox :GnRH cre mice show a total absence of GnRH expression in the adult. We performed lineage tracing in Vax1 flox/flox :GnRH cre :RosaLacZ mice which proved GnRH neurons to be alive, but incapable of expressing GnRH. The absence of GnRH leads to delayed puberty, hypogonadism and complete infertility in both sexes. Finally, using the immortalized model GnRH neuron cell lines, GN11 and

Assessment of the societal and individual preferences for fertility treatment in Australia: study protocol for stated preference discrete choice experiments

PubMed Central

Donnolley, Natasha; Shanahan, Marian; Chambers, Georgina M

2018-01-01

Introduction In Australia, societal and individual preferences for funding fertility treatment remain largely unknown. This has resulted in a lack of evidence about willingness to pay (WTP) for fertility treatment by either the general population (the funders) or infertile individuals (who directly benefit). Using a stated preference discrete choice experiment (SPDCE) approach has been suggested as a more appropriate method to inform economic evaluations of fertility treatment. We outline the protocol for an ongoing study which aims to assess fertility treatment preferences of both the general population and infertile individuals, and indirectly estimate their WTP for fertility treatment. Methods and analysis Two separate but related SPDCEs will be conducted for two population samples—the general population and infertile individuals—to elicit preferences for fertility treatment to indirectly estimate WTP. We describe the qualitative work to be undertaken to design the SPDCEs. We will use D-efficient fractional experimental designs informed by prior coefficients from the pilot surveys. The mode of administration for the SPDCE is also discussed. The final results will be analysed using mixed logit or latent class model. Ethics and dissemination This study is being funded by the Australian National Health and Medical Research Council (NHMRC) project grant AP1104543 and has been approved by the University of New South Wales Human Research Ethics Committee (HEC 17255) and a fertility clinic’s ethics committee. Findings of the study will be disseminated in peer-reviewed journals and presented at various conferences. A lay summary of the results will be made publicly available on the University of New South Wales National Perinatal Epidemiology and Statistics Unit website. Our results will contribute to the development of an evidence-based policy framework for the provision of cost-effective and patient-centred fertility treatment in Australia. PMID:29444788

Injurious effects of curcumin on maturation of mouse oocytes, fertilization and fetal development via apoptosis.

PubMed

Chen, Chia-Chi; Chan, Wen-Hsiung

2012-01-01

Curcumin, a common dietary pigment and spice, is a hydrophobic polyphenol derived from the rhizome of the herb Curcuma longa. Previously, we reported a cytotoxic effect of curcumin on mouse embryonic stem cells and blastocysts and its association with defects in subsequent development. In the present study, we further investigated the effects of curcumin on oocyte maturation and subsequent pre- and post-implantation development, both in vitro and in vivo. Notably, curcumin induced a significant reduction in the rate of oocyte maturation, fertilization, and in vitro embryonic development. Treatment of oocytes with curcumin during in vitro maturation (IVM) led to increased resorption of postimplantation embryos and decreased fetal weight. Experiments with an in vivo mouse model disclosed that consumption of drinking water containing 40 μM curcumin led to decreased oocyte maturation and in vitro fertilization as well as early embryonic developmental injury. Finally, pretreatment with a caspase-3-specific inhibitor effectively prevented curcumin-triggered injury effects, suggesting that embryo impairment by curcumin occurs mainly via a caspase-dependent apoptotic process.

Hispanic Familism Reconsidered: Ethnic Differences in Perceived Value of Children and Fertility Intentions

PubMed Central

Hartnett, Caroline Sten; Parrado, Emilio A.

2013-01-01

Familism has been described as a cultural trait that might explain why the fertility of Hispanic women remains higher than non-Hispanic White women. Still, few studies have analyzed group differences in childbearing attitudes. This paper focuses on two dimensions of childbearing orientation: social value of children and fertility intentions. Using the National Survey of Family Growth we find limited support for the idea that familism undergirds differentials in fertility between native-born Hispanics and Whites. However, for foreign-born Hispanics, there are some differences in the perceived value of children compared with Whites, and these differences could contribute to fertility differentials. PMID:24068847

The effects of Di-(2-ethylhexyl)-phthalate exposure on fertilization and embryonic development in vitro and testicular genomic mutation in vivo.

PubMed

Huang, Xue-Feng; Li, Yan; Gu, Yi-Hua; Liu, Miao; Xu, Yan; Yuan, Yao; Sun, Fei; Zhang, Hui-Qin; Shi, Hui-Juan

2012-01-01

The present study was undertaken to determine the reproductive hazards of Di-(2-ethylhexyl)-phthalate (DEHP) on mouse spermatozoa and embryos in vitro and genomic changes in vivo. Direct low-level DEHP exposure (1 μg/ml) on spermatozoa and embryos was investigated by in vitro fertilization (IVF) process, culture of preimplanted embryos in DEHP-supplemented medium and embryo transfer to achieve full term development. Big Blue® transgenic mouse model was employed to evaluate the mutagenesis of testicular genome with in vivo exposure concentration of DEHP (500 mg/kg/day). Generally, DEHP-treated spermatozoa (1 μg/ml, 30 min) presented reduced fertilization ability (P<0.05) and the resultant embryos had decreased developmental potential compared to DMSO controls (P<0.05). Meanwhile, the transferred 2-cell stage embryos derived from treated spermatozoa also exhibited decreased birth rate than that of control (P<0.05). When fertilized oocytes or 2-cell stage embryos were recovered by in vivo fertilization (without treatment) and then exposed to DEHP, the subsequent development proceed to blastocysts was different, fertilized oocytes were significantly affected (P<0.05) whereas developmental progression of 2-cell stage embryos was similar to controls (P>0.05). Testes of the Big Blue® transgenic mice treated with DEHP for 4 weeks indicated an approximately 3-fold increase in genomic DNA mutation frequency compared with controls (P<0.05). These findings unveiled the hazardous effects of direct low-level exposure of DEHP on spermatozoa's fertilization ability as well as embryonic development, and proved that in vivo DEHP exposure posed mutagenic risks in the reproductive organ - at least in testes, are of great concern to human male reproductive health.

Seasonal development of loblolly pine lateral roots in response to stand density and fertilization

Treesearch

M.A. Sword

1998-01-01

In 1989, two levels each of stand density and fertilization treatments were factorially established in a 9-year-old loblolly pine plantation on a P-deficient Gulf Coastal Plain site in Rapides Parish, Louisiana, USA. In 1995, a second thinning was conducted on the previously thinned plots and fertilizer was re-applied to the previously fertilized plots. The morphology...

Fertility and Infertility.

ERIC Educational Resources Information Center

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…

Abnormal assembly of annulate lamellae and nuclear pore complexes coincides with fertilization arrest at the pronuclear stage of human zygotic development.

PubMed

Rawe, V Y; Olmedo, S Brugo; Nodar, F N; Ponzio, R; Sutovsky, P

2003-03-01

The assembly of nuclear pore complexes (NPC) and their cytoplasmic stacks, annulate lamellae (AL), promote normal nucleocytoplasmic trafficking and accompany pronuclear development within the mammalian zygote. Previous studies showed that a percentage of human oocytes fertilized in vitro failed to develop normal pronuclei and cleave within 40-48 h post insemination. We hypothesized that an aberrant recruitment of NPC proteins, nucleoporins and/or NPC preassembled into AL, might accompany human fertilization arrest. We explored NPC and AL assembly in unfertilized human oocytes, and fertilized and arrested zygotes by immunofluorescence with an NPC- and AL-specific antibody, mAb 414, and by transmission electron microscopy. Major NPC or AL assembly was not observed in the unfertilized human oocytes. Once fertilization took place, the formation of AL was observed throughout the cytoplasm and near the developing pronuclei with NPC. On the contrary, NPC assembly was disrupted in the arrested zygotes, whereas AL were clustered into large sheaths. This was accompanied by the lack of NPC incorporation into the nuclear envelopes. We conclude that the aberrant assembly of NPC and AL coincides with early developmental failure in humans.

Do in vitro fertilization treatments result in healthy babies?

PubMed

Kaartinen, Noora; Tinkanen, Helena

In Finland, the proportion of children born as a result of in vitro fertilization treatments is annually approximately 3.3%, and the percentage proportion of the population is growing. Their general somatic health status and cognitive development do not differ from spontaneously fertilized children. In vitro fertilization treatments are, however, associated with a slightly elevated risk of preterm delivery, low birth weight and structural abnormalities. The risk of childhood cancer does not appear to be increased in IVF children. The in vitro fertilization process affects the embryonic epigenome, which organizes itself during early embryonic development. These changes may influence the phenotype and health profile of the unborn child. The effect of in vitro fertilization treatments on an individual's long-term health is poorly understood, requiring prospective follow-up studies with sufficiently large datasets. In vitro fertilization treatments are the most effective way to treat infertility, and the treatments are generally safe both for the future mother and the baby being born.

The study of fertility and fertility change in tropical Africa.

PubMed

Caldwell, J C

1976-09-01

This paper explores what little is known about fertility and fertility trends in tropical Africa and methods for obtaining more information. The most fundamental barrier at present is failure to make the fullest effort in applying the techniques that are available to already collected data. Present emphasis should be on elucidating the forces that sustain higher fertility and factors that may lead to changing fertility from smaller studies of high quality design. Currently available data have many errors and the region is at an early stage of demographic transition: vital registration schemes are nonexistent, survey and census data are so incomplete that vital rates worked out directly from the data are of little value, and fertility is probably close to being constant. Despite the ability of new methods for data analysis, e.g., Brass, Coale Demeny approach, problems exist in the following areas ascertaining fertility changes: methodological limitations, collection of data, and the detection and prediction of fertility change. Present fertility findings are summarized, the most significant being that tropical African fertility is not far above stated desired family size, which is very high in comparison with the rest of the world. Sources of data for making statements about fertility behavior are explored and research needs delineated. Priority areas should include: better fertility measures; more KAP type information for francophone Africa; emphasis on links between antinatal practice and fertility levels; study of 1 country over time using KAP indicators; motivations for fertility control; real cost of children at village family level; spread of antinatal practices, finding measures of completed behavior; and exploration of the financing of children's education in relation to attempts to limit family size. The Changing African Family Project, planned as a collaborative effort by researchers in more than 10 countries and designed to answer these questions, is

Toward precision medicine for preserving fertility in cancer patients: existing and emerging fertility preservation options for women

PubMed Central

Woodruff, Teresa K.

2016-01-01

As the number of young cancer survivors increases, quality of life after cancer treatment is becoming an ever more important consideration. According to a report from the American Cancer Society, approximately 810,170 women were diagnosed with cancer in 2015 in the United States. Among female cancer survivors, 1 in 250 are of reproductive age. Anticancer therapies can result in infertility or sterility and can have long-term negative effects on bone health, cardiovascular health as a result of reproductive endocrine function. Fertility preservation has been identified by many young patients diagnosed with cancer as second only to survival in terms of importance. The development of fertility preservation technologies aims to help patients diagnosed with cancer to preserve or protect their fertility prior to exposure to chemo- or radiation therapy, thus improving their chances of having a family and enhancing their quality of life as a cancer survivor. Currently, sperm, egg, and embryo banking are standard of care for preserving fertility for reproductive-age cancer patients; ovarian tissue cryopreservation is still considered experimental. Adoption and surrogate may also need to be considered. All patients should receive information about the fertility risks associated with their cancer treatment and the fertility preservation options available in a timely manner, whether or not they decide to ultimately pursue fertility preservation. Because of the ever expanding number of options for treating cancer and preserving fertility, there is now an opportunity to take a precision medicine approach to informing patients about the fertility risks associated with their cancer treatment and the fertility preservation options that are available to them. PMID:26768785

Ready, Willing, and Able? Impediments to the Onset of Marital Fertility Decline in the United States.

PubMed

Hacker, J David

2016-12-01

This study relies on IPUMS samples of the 1850, 1860, 1870, and 1880 censuses, aggregate census data, and the timing of state laws criminalizing abortion to construct regional estimates of marital fertility in the United States and estimate correlates of marital fertility. The results show a significant lag between the onset of marital fertility decline in the nation's northeastern census divisions and its onset in western and southern census divisions. Empirical models indicate the presence of cultural, economic, and legal impediments to the diffusion of marital fertility control and illustrate the need for more inclusive models of fertility decline.

Fertilizer Nutrient Leaching and Nutrient Mobility: A Simple Laboratory Exercise.

ERIC Educational Resources Information Center

Owens, D. S.; Johnson, G. V.

1996-01-01

Describes an exercise developed to demonstrate the degree to which nitrogen, phosphorus, and potassium fertilizers move through different soils. The results support the common practices of broadcasting nitrogen fertilizer and banding phosphorus and potassium fertilizers. (DDR)

Fertilization capacity of cryopreserved Iberian ibex epididymal sperm in a heterologous in vitro fertilization assay.

PubMed

López-Saucedo, J; Santiago-Moreno, J; Fierro, R; Izquierdo, D; Coloma, M A; Catalá, M G; Jiménez, I; Paramio, M T

2015-02-01

In vitro fertilization (IVF) can be used to assess the fertilization capacity of sperm. Heterologous IVF may be useful when assessing that of wild animals as it is often difficult to obtain adequate numbers of naturally corresponding oocytes. The aim of the present study was to assess the fertilization capacity of frozen-thawed ibex epididymal spermatozoa via heterologous IVF involving the oocytes of prepubertal domestic goats. The effect on fertilization and embryo development of adding oestrous sheep serum (ESS) to the fertilization medium was also examined. Cumulus-oocyte complexes (COCs) were matured in TCM-199 for 24-27 h at 38.5°C in a 5% CO2 in air atmosphere. Frozen-thawed epididymal spermatozoa were selected by density gradient centrifugation. After maturation, the oocytes were co-incubated with spermatozoa in synthetic oviductal fluid (SOF) with different concentrations of ESS: SOF-C (0%), SOF-2 (2%) and SOF-20 (20%). At 17 h post-insemination (hpi), zygotes with one female and one male pronucleus (2PN) were categorised as normal; zygotes with 3PN were recorded as polyspermic, and oocytes with 1PN as asynchronous. Cleavage and blastocyst development were assessed at 48 and 168 hpi respectively. The percentage of zygotes with 2PN was higher in the SOF-2 than in the SOF-20 treatment group (27.7% versus 2.9% P < 0.05). The percentage of blastocysts formed with the SOF-C, SOF-2 and SOF-20 treatments were 1.1%, 7.5% and 0% respectively. These results show that the presence of 2% ESS achieves better results than the use of no serum or the standard 20% concentration. Heterologous IVF may be an effective method for predicting the fertilization capacity of ibex spermatozoa, and therefore perhaps that of other wild mountain ungulates.

Injurious Effects of Emodin on Maturation of Mouse Oocytes, Fertilization and Fetal Development via Apoptosis

PubMed Central

Chang, Mei-Hui; Chang, Shao-Chung; Chan, Wen-Hsiung

2012-01-01

Emodin (1,3,8-trihydroxy-6-methylanthraquinone), a major constituent of rhubarb, has a wide range of therapeutic applications. Previous studies have established that emodin induces apoptosis in the inner cell mass and trophectoderm of mouse blastocysts and leads to decreased embryonic development and viability, indicating a role as an injury risk factor for normal embryonic development. However, the mechanisms underlying its hazardous effects have yet to be characterized. In the current study, we further investigated the effects of emodin on oocyte maturation and subsequent pre- and post-implantation development, both in vitro and in vivo. Notably, emodin induced a significant reduction in the rates of oocyte maturation, fertilization, and in vitro embryonic development. Treatment of oocytes with emodin during in vitro maturation (IVM) led to increased resorption of postimplantation embryos and decreased fetal weight. Experiments using an in vivo mouse model disclosed that consumption of drinking water containing 20–40 μM emodin led to decreased oocyte maturation and in vitro fertilization, as well as early embryonic developmental injury. Notably, pretreatment with a caspase-3-specific inhibitor effectively prevented emodin-triggered injury effects, suggesting that impairment of embryo development occurs via a caspase-dependent apoptotic process. PMID:23203041

Improving fertility of dairy cattle using translational genomics

USDA-ARS?s Scientific Manuscript database

Selection for higher milk production in United States dairy cattle has been very successful during the past 50 years, however today’s lactating dairy cows exhibit a high incidence of subfertility and infertility with a national pregnancy rate of only 15%. An integrated approach to improve fertility ...

Perennial crop phase effects on soil fertility

USDA-ARS?s Scientific Manuscript database

There is a need to develop agricultural management systems that enhance soil fertility and reduce reliance on external inputs. Perennial phases in crop rotations are effective at restoring soil fertility, though little information exists in the northern Great Plains regarding soil-based outcomes re...

Sensor-based precision fertilization for field crops

USDA-ARS?s Scientific Manuscript database

From the development of the first viable variable-rate fertilizer systems in the upper Midwest USA, precision agriculture is now approaching three decades old. Early precision fertilization practice relied on laboratory analysis of soil samples collected on a spatial pattern to define the nutrient-s...

Third world programs confront adolescent fertility.

PubMed

1978-08-01

Recently, there have been efforts to identify workable youth programs and effective research projects that could deal with the problem of adolescent fertility. Typical objectives identified at various conferences concerned with this problem included the following: 1) focus attention on the adverse medical and socioeconomic efforts of early pregnancy; 2) draw attention to the current dimensions of adolescent fertility and its changing patterns; 3) encourage development of programs; and 4) impress decision makers with the importance of programs for adolescents. These conferences express a sense of urgency in developing programs before teen-age pregnancy reaches epidemic proportions. Most of the projects already underway are still pilot efforts and have an impact on a very small sector of the population. Yet, they are positive steps toward a solution of the rising problems of adolescent fertility and help to identify workable solutions. A few of these projects -- underway in Colombia, Argentina, Chile, Cost Rica, Guatemala and Mexico -- are reviewed. The consensus of all conferences held to date has been that cross-cultural interchanges is crucial to the spread of programs and ideas that can be adapted to local conditions. 2 key recommendations have emerged from a meeting of donor and support agencies held in Washington, D.C. in May: 1) a major conference should take place during the International Year of the Child (1979) that would focus on early sexual activity and fertility and 2) an Adolescent Fertility Council should be appointed. An Adolescent Fertility Council would provide a structure to correlate and stimulate interaction, while recognizing that country and culture specific programs are essential.

The rise of adjusted fertilizer recommendations and the 1946 establishment of the Soil Service of Belgium

NASA Astrophysics Data System (ADS)

de Winter, H.

2012-04-01

The scientific branch of soil science was worldwide firmly established at the beginning of the 20th century. In this period, it developed strongly in various countries. During the thirties, interest in soil science and its subfields (plant nutrition, soil hydrology, soil microbiology,...) grew even more strongly, which can be demonstrated by the rapid growth of 'soil research institutions' all over the world. In Belgium, it was professor priest Joseph Baeyens (1885-1990) who established the first chair of 'Soil Science' in 1935 at the Catholic University of Leuven. He can be considered as a Belgian pioneer in soil fertility research. After having done prospective soil research in the Belgian Congo, the Belgium government supported him to start the same study for Belgian soils. This innovative soil fertility research was done at the Soil Science Institute of the University of Leuven, which was established and lead by Joseph Baeyens himself. His goal was to determine the fertility norms of the Belgian farmlands. After this large-scale study was done, the fertility norms and associated fertilizer needs could be presented to farmers all over the country. The overall goal was to increase crop production and to minimize fertilizer costs. When Baeyens started to spread his knowledge to the farmers, it would not take long before the demand for his knowledge grew significantly. This lead in 1946 to the erection of the Soil Service of Belgium: an independent laboratory and research institution, analyzing soil samples in order to customize fertilizer recommendations for farmers. This paper discusses the establishment and-development of the SSB. It covers the period between 1930 and 1950. Following questions will be addressed: How unique was the development of SSB on a national and international level? How did research take shape at the SSB? How did the SSB obtain its place in the Belgian agricultural network? What was the role of the government ? And finally, how did the

Evaluation of bull fertility in dairy and beef cattle using cow field data.

PubMed

Berry, D P; Evans, R D; Mc Parland, S

2011-01-01

A successful outcome to a given service is a combination of both male and female fertility. Despite this, most national evaluations for fertility are generally confined to female fertility with evaluations for male fertility commonly undertaken by individual breeding organisations and generally not made public. The objective of this study was to define a pertinent male fertility trait for seasonal calving production systems, and to develop a multiple regression mixed model that may be used to evaluate male fertility at a national level. The data included in the study after editing consisted of 361,412 artificial inseminations from 206,683 cow-lactations (134,911 cows) in 2,843 commercial dairy and beef herds. Fixed effects associated with whether a successful pregnancy ensued (pregnant = 1) or not (pregnant = 0) from a given service were year by month of service, day of the week, days since calving, cow parity, level of calving difficulty experienced, whether or not the previous calving was associated with perinatal mortality, and age of the service bull at the date of insemination. Non-additive genetic effects such as heterosis and recombination loss as well as inbreeding level of the service bull, dam or mating were not associated with a successful pregnancy; there was no difference in pregnancy rate between fresh or frozen semen. Random effects included in the model were the additive genetic effect of the cow, as well as a within lactation and across lactation permanent environmental effect of the cow; pedigree group effects based on cow breed were also included via the relationship matrix. Temporal differences in the AI technician and service bull were also included as random effects. A difference in five percentage units in male fertility was evident between the average effects of different dairy and beef breeds. The correlation between raw pregnancy rates for bulls with more than 100 services (n = 431) and service bull solutions from the mixed model analysis

Determinants of fertility in Malaysia -- how much do we know?

PubMed

Ying, S L

1992-03-01

Chinese and Indian fertility have continued to decline in the 1980s while Malay fertility has stabilized and even risen slightly. The objective of this literature review is to examine the literature on the role of socioeconomic determinants of family formation and childbearing when there are ethnic compositional differences and to examine the evidence for and explanation of why there are different ethnic responses to different socioeconomic variables. Recent fertility trends are identified. Fertility was high in 1957 among all ethnic groups, and Malay fertility was lowest. Chinese fertility declined first in the early 1960s. Malay fertility began its decline after 1964. Indian fertility did not fall until the late 1960s but was the most rapid. In 1966, the National Family Planning Program was initiated and targets were set for 2% growth by 1985. During the 1970s the proportion of Malay acceptors increased, but 10 years later the proportion using efficient methods of contraception declined. In the review of studies on socioeconomic determinants of fertility, women's education is usually associated negatively with family size through delayed age at first marriage, but the effects may vary within ethnic groups. Stronger associations between education and fertility are found for urban and rural Chinese and urban Indians, but socioeconomic factors such as husband's education and family income replace education in importance. The effect of education on family planning and contraceptive usage is more consistent across ethnic groups. Female employment, income, urbanization, migration, infant mortality, and other socioeconomic factors and their association with fertility are also reviewed. Ethnicity affects method of use, as does religion. Malays desire larger families, marry at earlier ages, and are less likely to use contraception which cannot be explained by compositional effects, and are weakly explained by cultural factors. The rise in Malay fertility may be explained

Environmental evaluation of the life cycle of elephant grass fertilization-Cenchrus purpureus (Schumach.) Morrone-using chemical fertilization and biosolids.

PubMed

Neves, Talles Iwasawa; Uyeda, Claudio Augusto; Carvalho, Monica; Abrahão, Raphael

2017-12-19

Law 12305/10, National Solid Waste Policy of Brazil, banned the disposal in landfills of any solid waste that could be converted to another use. Sludge produced at Industrial Wastewater Treatment Plants, which contains components characteristic of fertilizers, falls into this category. This type of sludge, also known as a biosolid, has great potential to replace commercial chemical fertilization. The use of biosolids in agriculture allows for compliance with new legislation, reducing the burden on landfills and reusing a waste product. The present paper utilizes the life cycle assessment methodology to compare the carbon footprint associated with the use of different quantities of biosolid and selected chemical fertilizers in the production of elephant grass. The IPCC 2013 GWP 100a method, which is based on data published by the Intergovernmental Panel on Climate Change, was selected as the environmental assessment method. The method expresses the emissions of greenhouse gases generated, in kilograms of CO 2 equivalent, over a time horizon of 100 years. The biosolid quantities used were based on the Brazilian Environment Council Resolution 375. The chemical fertilizer used contained urea, simple superphosphate, and potassium chloride. The use of biosolids in the amounts calculated according to Brazilian standards resulted in a carbon footprint approximately 17.7% lower than the use of the chemical fertilization mix, with similar productivity in both cases. The transportation of biosolids to the experimental area was responsible for the majority of emissions associated with the use of biosolids. Urea synthesis was the largest contributor to emissions resulting from the use of commercial chemical fertilizer, accounting for 73.6% of total emissions.

County-level estimates of nitrogen and phosphorus fertilizer use in the United States, 1945 to 1985

USGS Publications Warehouse

Alexander, Richard B.; Smith, Richard A.

1990-01-01

Estimates of nitrogen and phosphorus fertilizer use were made for counties in the United States for the period 1945 to 1985. County fertilizer use estimates were obtained through the disaggregation of state-level fertilizer use in proportion to the amount of state fertilized acreage reported to exist in counties. Numerical values of nitrogen and phosphorus fertilizer use by county are not presented in the text of this report because of the size of the data file, but are available in machine-readable form upon request. Graphical summaries of national, state, and county nitrogen and phosphorus fertilizer use are presented to briefly describe the spatial and temporal variability that exist in the data.

Chinese women's participation in fertility discussions.

PubMed

Li, L

1993-01-01

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

The Effects of Di-(2-ethylhexyl)-phthalate Exposure on Fertilization and Embryonic Development In Vitro and Testicular Genomic Mutation In Vivo

PubMed Central

Gu, Yi-Hua; Liu, Miao; Xu, Yan; Yuan, Yao; Sun, Fei; Zhang, Hui-Qin; Shi, Hui-Juan

2012-01-01

The present study was undertaken to determine the reproductive hazards of Di-(2-ethylhexyl)-phthalate (DEHP) on mouse spermatozoa and embryos in vitro and genomic changes in vivo. Direct low-level DEHP exposure (1 μg/ml) on spermatozoa and embryos was investigated by in vitro fertilization (IVF) process, culture of preimplanted embryos in DEHP-supplemented medium and embryo transfer to achieve full term development. Big Blue® transgenic mouse model was employed to evaluate the mutagenesis of testicular genome with in vivo exposure concentration of DEHP (500 mg/kg/day). Generally, DEHP-treated spermatozoa (1 μg/ml, 30 min) presented reduced fertilization ability (P<0.05) and the resultant embryos had decreased developmental potential compared to DMSO controls (P<0.05). Meanwhile, the transferred 2-cell stage embryos derived from treated spermatozoa also exhibited decreased birth rate than that of control (P<0.05). When fertilized oocytes or 2-cell stage embryos were recovered by in vivo fertilization (without treatment) and then exposed to DEHP, the subsequent development proceed to blastocysts was different, fertilized oocytes were significantly affected (P<0.05) whereas developmental progression of 2-cell stage embryos was similar to controls (P>0.05). Testes of the Big Blue® transgenic mice treated with DEHP for 4 weeks indicated an approximately 3-fold increase in genomic DNA mutation frequency compared with controls (P<0.05). These findings unveiled the hazardous effects of direct low-level exposure of DEHP on spermatozoa's fertilization ability as well as embryonic development, and proved that in vivo DEHP exposure posed mutagenic risks in the reproductive organ – at least in testes, are of great concern to human male reproductive health. PMID:23226291

Fertility Intentions, Career Considerations and Subsequent Births: The Moderating Effects of Women's Work Hours.

PubMed

Shreffler, Karina M; Johnson, David R

2013-09-01

Prior research indicates a negative relationship between women's labor force participation and fertility at the individual level in the United States, but little is known about the reasons for this relationship beyond work hours. We employed discrete event history models using panel data from the National Survey of Families and Households ( N = 2,411) and found that the importance of career considerations mediates the work hours/fertility relationship. Further, fertility intentions and the importance of career considerations were more predictive of birth outcomes as women's work hours increase. Ultimately, our findings challenge the assumption that working more hours is the direct cause for employed women having fewer children and highlight the importance of career and fertility preferences in fertility outcomes.

Fertility preservation 2

PubMed Central

De Vos, Michel; Smitz, Johan; Woodruff, Teresa K

2014-01-01

Enhanced long-term survival rates of young women with cancer and advances in reproductive medicine and cryobiology have culminated in an increased interest in fertility preservation methods in girls and young women with cancer. Present data suggest that young patients with cancer should be referred for fertility preservation counselling quickly to help with their coping process. Although the clinical application of novel developments, including oocyte vitrification and oocyte maturation in vitro, has resulted in reasonable success rates in assisted reproduction programmes, experience with these techniques in the setting of fertility preservation is in its infancy. It is hoped that these and other approaches, some of which are still regarded as experimental (eg, ovarian tissue cryopreservation, pharmacological protection against gonadotoxic agents, in-vitro follicle growth, and follicle transplantation) will be optimised and become established within the next decade. Unravelling the complex mechanisms of activation and suppression of follicle growth will not only expand the care of thousands of women diagnosed with cancer, but also inform the care of millions of women confronted with reduced reproductive fitness because of ageing. PMID:25283571

Commercial fertilizers 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berry, J.T.; Montgomery, M.H.

1992-12-01

Fertilizer consumption information in the USA for 1992 submitted by state regulatory officials is presented. This includes total sales or shipments for farm and non-farm use. Liming materials were excluded. Materials used for manufacture or blending of reported fertilizers or for use in other fertilizers are excluded to avoid double-counting. The consumption of multiple-nutrient and single-nutrient fertilizers is listed. Dry bulk, fluid, and bagged classes are given. Typical fertilizers include: anhydrous ammonia, aqua ammonia, nitrogen solutions, urea, ammonium nitrates, ammonium sulfates, phosphoric acid, superphosphates, potassium chlorides, and potassium sulfates.

Medical and Psychosocial Aspects of Fertility After Cancer

PubMed Central

Duffy, Christine; Allen, Susan

2009-01-01

Survival for cancer has improved significantly in the last 25 years with excellent overall 5-year and 10-year survival rates. Hence, the majority of young women diagnosed with cancer can expect to live for decades, making quality of life issues such as fertility increasingly important. Risks of infertility vary based on the chemotherapy and treatments employed, as well as a woman’s age. In general, younger women are less likely to experience permanent amenorrhea than older women, but even women who continue to menstruate have a greatly increased risk of premature menopause. Options for cancer patients entering chemotherapy treatment who wish to preserve fertility range from clinically well-established techniques such as embryo cryopreservation to more experimental techniques such as ovarian tissue cryopreservation. Pregnancy does not appear to increase the risk of cancer recurrence. Discussion of fertility issues in premenopausal women diagnosed with cancer present important challenges to the provider and to the patient. However, failure to discuss these options adequately can have lasting negative consequences on a woman’s quality of life. Physician education interventions should seek to improve the knowledge of fertility preservations options, and of locally and nationally available resources. PMID:19197170

Development of a Spanish language fertility educational brochure for pediatric oncology families.

PubMed

Murphy, D; Kashal, P; Quinn, G P; Sawczyn, K K; Termuhlen, A M

2014-08-01

Education materials detailing fertility preservation options geared towards pediatric oncology patients are inadequately available, particularly materials that are culturally tailored. An English language pediatric fertility preservation brochure was developed in 2011, and given the significance of family building among Hispanics, it is important to transcreate materials for these audiences using learner verification to explore the unique preferences of the population. Qualitative face-to-face interviews and focus groups. Spanish-speaking patients (n = 10), parents (n = 10), and healthcare providers (n = 5). Suggestions for revisions were tested with focus groups of the same population (N = 16). Design, readability, likelihood to read, and overall opinion. Feedback was organized into 2 distinct themes: design and reader action. Overall the majority of parents and patients wanted personal accounts of other patients who had undergone fertility preservation, as well as photos of actual patients. The medical terminology in the brochure was acceptable and understood by most. The majority of participants who preferred the design with vivid colors and patterns explained this was because that brochure also contained more relevant information; however, both brochures had identical information. Many participants explained they would be receptive to receiving the brochure and the reproductive health information should be reinforced throughout cancer care. A learner verification approach to create pediatric educational materials can judiciously identify unique preferences for information. These results will be utilized to educate Spanish-speaking pediatric oncology patients and their parents to improve decision-making processes regarding future parenthood. Copyright © 2014 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Heat stress during in vitro fertilization decreases fertilization success by disrupting anti-polyspermy systems of the oocytes.

PubMed

Sakatani, Miki; Yamanaka, Kenichi; Balboula, Ahmed Z; Takenouchi, Naoki; Takahashi, Masashi

2015-01-01

Low pregnancy rates during the summer are due, in part, to reduced fertilization. Given that elevated temperature is associated with this season, we investigated the effect of heat stress during fertilization using an in vitro model. Three experiments were performed to determine the mechanism by which exposure to elevated temperature disrupts fertilization. Oocytes were fertilized for 6 hr at 38.5°C or 41.0°C or 40.0°C with non-pre-incubated sperm, or for 6 hr at 38.5°C with sperm that had been pre-incubated at 38.5°C or 41.0°C for 4 hr. In each experiment, zygotes were cultured at 38.5°C in 5% CO(2) and 5% O(2). Rates of cleavage and blasocyst formation were reduced when fertilization occurs at elevated temperatures. The percent of sperm classified as alive, using fluorescein diacetate labeling, was decreased by pre-incubation and fertilization at 40.0°C. Although no difference was observed in sperm penetration rate, polyspermy tended to be increased by heat stress during fertilization. The zona pellucidae of zygotes formed following fertilization at 40.0°C for 6 hr were more sensitive to digestion with pronase. Furthermore, these zygotes exhibited higher hydrogen peroxide levels, measured by 2,7-dihydrodichlorofluorescein diacetate staining, and showed increased transcript abundance for HSPA1A, a gene involved in the heat-shock response, but decreased transcript abundance for UCHL1, a gene involved in preventing polyspermy. Results indicate that heat stress during fertilization is lethal to sperm, and causes oxidative stress, altered transcript abundance, and a defective block to polyspermy in the zygote. Thus, an increase in polyspermy is likely one cause of the reduced competency of zygotes fertilized under elevated temperatures to develop to the blastocyst stage. © 2014 Wiley Periodicals, Inc.

Young female cancer patients' experiences with fertility counselling and fertility preservation-a qualitative small-scale study within the Danish health care setting.

PubMed

Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T

2016-07-14

Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before initiation of cancer treatment. Participants were interviewed at a place chosen by them, and interviews were recorded and transcribed verbatim. Data were analysed using systematic text condensation developed by Malterud and inspired by Giorgi's phenomenological analysis. None of the participants were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how the possibility of fertility preservation removed a huge concern and enabled them to concentrate on their cancer treatment and on getting better. Overall, the specialized fertility counselling and treatment to preserve fertility was highly valued. The women felt it gave them a choice about their future fertility. The fertility expert presented the various fertility-preserving scenarios, and the women were content that they had an actual choice.

Construction of conditional acid ceramidase knockout mice and in vivo effects on oocyte development and fertility.

PubMed

Eliyahu, Efrat; Shtraizent, Nataly; Shalgi, Ruth; Schuchman, Edward H

2012-01-01

The number of resting follicles in the ovary and their successful maturation during development define the fertile female lifespan. Oocytes, enclosed within follicles, are subject to natural selection, and the majority will undergo apoptosis during prenatal life through adulthood. Our previous studies revealed high levels of the lipid hydrolase, acid ceramidase (AC), in human and mouse oocytes, follicular fluid and cumulus cells. In addition, supplementation of in vitro fertilization media with recombinant AC enhanced the survival of oocytes and preimplantation embryos. Herein we constructed and used a conditional knockout mouse model of AC deficiency (cACKO) to further investigate the role of this enzyme in oocyte survival in vivo. Immunohistochemical staining, activity assays, and western blot analysis revealed that AC expression was high in the ovaries of normal mice, particularly in the theca cells. After induction of the AC gene knockout with tamoxifen (TM), AC levels decreased in ovaries, and ceramide was correspondingly elevated. A novel immunostaining method was developed to visualize follicles at various stages, and together with light microscopic examination, the transition of the follicle from the secondary to antral stage was found to be defective in the absence of AC. Western blot analysis showed elevated BAX and PARP expression in TM-treated cACKO mouse ovaries compared to control animals. In parallel, the levels of BCL-2 and anti-Mullerian hormone, a marker of ovarian reserve, were decreased. In addition to the above, there was a significant decrease in fertility observed in the TM-treated cACKO mice. Together, these data suggest that AC plays an important role in the preservation of fertility by maintaining low ceramide levels and preventing apoptosis of theca cells, thereby promoting survival of the follicle during the transition from the secondary to antral stage. Copyright © 2012 S. Karger AG, Basel.

Physicians' perspectives and practices regarding the fertility management of obese patients.

PubMed

Harris, Isiah D; Python, Johanne; Roth, Lauren; Alvero, Ruben; Murray, Shona; Schlaff, William D

2011-10-01

To assess the practice patterns and personal beliefs of fertility physicians who care for obese patients seeking assisted reproduction, we conducted a national survey of fertility program directors from both private and academic practices and discovered that although few practices have firm guidelines regarding the management of obese patients, the overwhelming majority of providers believe that body mass index guidelines or cutoffs should exist. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

The effects of platelet lysate on maturation, fertilization and embryo development of NMRI mouse oocytes at germinal vesicle stage.

PubMed

Pazoki, Hassan; Eimani, Hussein; Farokhi, Farah; Shahverdi, Abdol-Hossein; Tahaei, Leila Sadat

2016-04-01

Improving in vitro maturation could increase the rate of pregnancy from oocytes matured in vitro. Consequently, patients will be prevented from using gonadotropin with its related side effects. In this study, the maturation medium was enriched by platelet lysate (PL), then maturation and subsequent developments were monitored. Oocytes at germinal vesicle stage with cumulus cells (cumulus-oocyte complex) and without cumulus cells (denuded oocytes) were obtained from mature female mice. The maturation medium was enriched by 5 and 10 % PL and 5 % PL + 5 % fetal bovine serum (FBS) as experimental groups; the control groups' media consisted of 5 and 10 % FBS. After 18 h, the matured oocytes were collected and, after fertilization, subsequent development was monitored. The rates of maturation, fertilization and 2-cell embryo development for the denuded oocyte groups in experimental media 5 % PL and 5 % PL + 5 % FBS were significantly higher than those of the control groups ( P < 0.05), while the results for the cumulus-oocyte complex groups were similar between the experimental groups and control groups. The results of this study indicated that platelet lysate could improve the maturation rate in the absence of granulosa cells compared to media with FBS. This extract also had positive effects on fertilization and embryo development.

[Fertility preservation, contraception and menopause hormone therapy in women treated for rare ovarian tumors: Guidelines from the French national network dedicated to rare gynaecological cancer].

PubMed

Rousset-Jablonski, Christine; Selle, Fréderic; Adda-Herzog, Elodie; Planchamp, François; Selleret, Lise; Pomel, Christophe; Chabbert-Buffet, Nathalie; Daraï, Emile; Pautier, Patricia; Trémollières, Florence; Guyon, Frederic; Rouzier, Roman; Laurence, Valérie; Chopin, Nicolas; Faure-Conter, Cécile; Bentivegna, Enrica; Vacher-Lavenu, Marie-Cécile; Lhomme, Catherine; Floquet, Anne; Treilleux, Isabelle; Lecuru, Fabrice; Gouy, Sébastien; Kalbacher, Elsa; Genestie, Catherine; de la Motte Rouge, Thibault; Ferron, Gwenael; Devouassoux-Shisheboran, Mojgan; Kurtz, Jean-Emmanuel; Namer, Moise; Joly, Florence; Pujade-Lauraine, Eric; Grynberg, Michael; Querleu, Denis; Morice, Philippe; Gompel, Anne; Ray-Coquard, Isabelle

2018-03-01

Rare ovarian tumors include complex borderline ovarian tumors, sex-cord tumors, germ cell tumors, and rare epithelial tumors. Indications and modalities of fertility preservation, infertility management and contraindications for hormonal contraception or menopause hormone therapy are frequent issues in clinical practice. A panel of experts from the French national network dedicated to rare gynaecological cancers, and of experts in reproductive medicine and gynaecology have worked on guidelines about fertility preservation, contraception and menopause hormone therapy in women treated for ovarian rare tumors. A panel of 39 experts from different specialties contributed to the preparation of the guidelines, following the DELPHI method (formal consensus method). Statements were drafted after a systematic literature review, and then rated through two successive rounds. Thirty-five recommendations were selected, and concerned indications for fertility preservation, contraindications for ovarian stimulation (in the context of fertility preservation or for infertility management), contraceptive options (especially hormonal ones), and menopause hormone therapy for each tumor type. Overall, prudence has been recommended in the case of potentially hormone-sensitive tumors such as sex cord tumors, serous and endometrioid low-grade adenocarcinomas, as well as for high-risk serous borderline ovarian tumors. In the context of a scarce literature, a formal consensus method allowed the elaboration of guidelines, which will help clinicians in the management of these patients. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

Religious Affiliation and the Fertility of Married Couples.

ERIC Educational Resources Information Center

Mosher, William D.; Hendershot, Gerry E.

1984-01-01

Used data from two National Surveys of Family Growth (N=14,000) to estimate the fertility of married couples by religious group. Results are presented in terms of religious and racial differences, controlling for age, education and residence, and indicate that religious affiliation continues to be an indispensable datum. (JAC)

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

PubMed

Okun, Barbara S

2016-07-01

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

Should fertilization treatment start with reducing stress?

PubMed

Campagne, Daniel M

2006-07-01

In the past few decades, new and more efficient techniques to help solve fertility problems have become widely available throughout the developed world. These techniques include hormonal stimulation, ICSI, gamete intra-Fallopian transfer (GIFT) and IVF, and their cost is, on average, considerable. There is substantial initial evidence that the psychological disposition of the parents-to-be influences their fertility and thus the outcome of fertilization techniques. Many fertility treatments include consultation with a psychologist and do try to keep the stress produced by the treatment itself to a minimum, using concurrent therapy. However, the accumulating evidence points to the need to program medical fertility treatment, bearing in mind both chronic and acute stress levels, and to treat for their reduction before commencing the (actual) fertility treatment. There is ample evidence that lower stress levels mean better female and male natural fertility, though there is as yet no conclusive experimental evidence that lower stress levels result in better fertility treatment outcome. However, first reducing stress may diminish the number of treatment cycles needed before pregnancy is obtained, may prepare the couple for an initial failure of treatment or even make the more invasive techniques unnecessary. Primary psychological treatment for trait and state stress, being a less invasive method than IVF, ICSI or GIFT, is to be applied whenever indicated. Also, treatment and therapy to reduce stress, and in so doing enhance fertility, do not provoke the ethical and religious objections raised by infertility treatments.

Flower thermoregulation facilitates fertilization in Asian sacred lotus.

PubMed

Li, Jiao-Kun; Huang, Shuang-Quan

2009-05-01

The thermoregulatory flower of the Asian sacred lotus (Nelumbo nucifera) can maintain a relatively stable temperature despite great variations in ambient temperature during anthesis. The thermoregulation has been hypothesized to offer a direct energy reward for pollinators in lotus flowers. This study aims to examine whether the stable temperature maintained in the floral chamber influences the fertilization process and seed development. An artificial refrigeration instrument was employed to cool flowers during the fertilization process and post-fertilization period in an experimental population. The effect of temperature on post-pollination events was also examined by removing petals in two field populations. Treatments with low floral temperature did not reduce stigma receptivity or pollen viability in undehisced anthers. Low temperature during the fertilization period significantly decreased seed set per flower but low temperature during the phase of seed development had no effect, suggesting that temperature regulation by lotus flowers facilitated fertilization success. Hand-pollination treatments in two field populations indicated that seed set of flowers with petals removed was lower than that of intact flowers in north China, where ambient temperatures are low, but not in south China, confirming that reducing the temperature of carpels did influence post-pollination events. The experiments suggest that floral thermoregulation in lotus could enhance female reproductive success by facilitating fertilization.

The Impact of College Education on Fertility: Evidence for Heterogeneous Effects

PubMed Central

Brand, Jennie E.; Davis, Dwight

2012-01-01

As college going among women has increased, more women are going to college from backgrounds that previously would have precluded their attendance and completion. This affords us the opportunity and motivation to look at the effects of college on fertility across a range of social backgrounds and levels of early achievement. Despite a substantial literature on the effects of education on women’s fertility, researchers have not assessed variation in effects by selection into college. With data on U.S. women from the National Longitudinal Survey of Youth 1979, we examine effects of timely college attendance and completion on women’s fertility by the propensity to attend and complete college, using multilevel Poisson and discrete-time eventhistory models. Disaggregating the effects of college by propensity score strata, we find that the fertility-decreasing college effect is concentrated among women from comparatively disadvantaged social backgrounds and low levels of early achievement. The effects of college on fertility attenuate as we observe women from backgrounds that are more predictive of college attendance and completion. PMID:21735305

Fall fertilization of Pinus resinosa seedlings: nutrient uptake, cold hardiness, and morphological development

Treesearch

M. Anisul Islam; Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

2009-01-01

Fertilization is an integral component of nursery culture for production of high quality seedlings for afforestation and reforestation because it can enhance plant growth, nutrient storage reserves, and resistance to biotic and abiotic stresses (Landis, 1985). While fertilizer is conventionally applied during spring and summer in accordance with the...

Synthesis of a novel slow-release potassium fertilizer from modified Pidgeon magnesium slag by potassium carbonate.

PubMed

Li, Yongling; Cheng, Fangqin

2016-08-01

A novel slow-release potassium fertilizer (SPF) was synthesized using Pidgeon magnesium slag (PMS) and potassium carbonate, which could minimize fertilizer nutrient loss and PMS disposal problems. Orthogonal experiments were conducted to determine the optimum conditions for synthesis. The potassium (K)-bearing compounds of SPF existed mainly in the form of crystalline phases Ca1.197K0.166SiO4, K2MgSiO4, and K4CaSi3O9, and in the noncrystalline phase. The active silicon content of SPF was 2.09 times as much as that of magnesium slag, and the slow-release character of SPF met the requirement for partly slow-release fertilizer in the national standard (GB/T23348-2009). The best models for describing the K release kinetics in water and 2% citric acid were the Elovich model and the first-order model, respectively. The heavy metal contents of SPF conformed to the national standard for organic-inorganic compound fertilizers, and the leaching mass concentrations of heavy metals and Fluorine were far lower than the limit values of the identification standard for hazardous waste identification for extraction toxicity (GB5085.3-2007), and also met the class II quality standard for ground water. The environmental risk of SPF is therefore very low, but because SPF is alkaline, its effect on soil pH should be taken into account. PMS is the solid waste resulting from the production of magnesium metal by Pidgeon's reduction process. Utilization of PMS in the high-technology and high-value areas may promote the high-efficiency development of worldwide collection metallic magnesium industry and contribute to the reduction of emissions of fine dust to air. This paper presents one of the new techniques in the use of PMS as a slow-release fertilizer by adding K2CO3. The product can serve as a very cost-effective and reliable artificial fertilizer.

Young female cancer patients’ experiences with fertility counselling and fertility preservation—a qualitative small-scale study within the Danish health care setting

PubMed Central

Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T.

2016-01-01

Introduction Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Methods Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before initiation of cancer treatment. Participants were interviewed at a place chosen by them, and interviews were recorded and transcribed verbatim. Data were analysed using systematic text condensation developed by Malterud and inspired by Giorgi’s phenomenological analysis. Results None of the participants were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how the possibility of fertility preservation removed a huge concern and enabled them to concentrate on their cancer treatment and on getting better. Conclusion Overall, the specialized fertility counselling and treatment to preserve fertility was highly valued. The women felt it gave them a choice about their future fertility. The fertility expert presented the various fertility-preserving scenarios, and the women were content that they had an actual choice. PMID:27413812

An Analysis of China's Fertilizer Policies: Impacts on the Industry, Food Security, and the Environment.

PubMed

Li, Yuxuan; Zhang, Weifeng; Ma, Lin; Huang, Gaoqiang; Oenema, Oene; Zhang, Fusuo; Dou, Zhengxia

2013-07-01

China has made remarkable strides in recent decades to grow enough food to feed 20% of the world's population with only 9% of the world's arable land. Meanwhile, the nation is experiencing exacerbated air and water pollution problems. Agricultural growth and the pollution aggravation are closely linked with policies affecting fertilizer production and use. Essentially nonexistent in 1950, China's fertilizer industry is now a robust conglomerate producing fertilizers in amounts that not only meet domestic demand but also contribute to international trade. The industry's growth stemmed from a series of policy progressions, featuring (i) a total control system with state ownership and central planning (1949-1984), (ii) a dual system of central planning and market adjustment (1985-1997), (iii) a market-driven system with government-mandated price caps (1998-2009), and (iv) a complete market-oriented system (since 2009). In conjunction with the policy changes were massive subsidy programs totaling more than $18 billion in 2010. The support policies and subsidies helped grow the industry and safeguard an adequate supply of fertilizers at affordable costs to farmers, but the artificially low-priced fertilizers also contributed to a nationwide trend of fertilizer overuse, leading to nutrient pollution. China needs innovative policies and programs to address food security and sustainability challenges. In this study, we review and analyze policies and programs related to China's fertilizer production and use in a 60-yr span (1950-2010) and discuss its impact on the development of the industry, food security, and pressing environmental issues. Finally, our study analyzes long-term trends in fertilizer use in China and offers some key viewpoints to stimulate debates among all stakeholders. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

IMPACT OF SEX COMPOSITION OF LIVING CHILDREN AND COUPLES' AGREEMENT ON SUBSEQUENT FERTILITY IN INDIA.

PubMed

Kastor, Anshul; Chatterjee, Sayantani

2017-11-23

The desire for children could be considered a reliable predictor of subsequent fertility. At the same time, the sex composition of surviving children, along with other demographic and socioeconomic factors, may affect a couple's fertility desire and, therefore, their subsequent fertility. This study examined the impact of the sex composition of living children and a couple's agreement on fertility desire on their subsequent fertility in India using data came from two rounds of nationally representative surveys: the India Human Development Survey (IHDS)-I (2004-05) and IHDS-II (2011-12). To understand which factors affect the chances of an additional pregnancy or childbirth, a random effects logistic regression model was applied to the panel data. It was found that the fertility desires of both marital partners were important in determining the chances of subsequent fertility. About 35% of the couples wanting to limit children had undergone pregnancy or childbirth, while 76% of the couples wanting more children had conceived or given birth to children. In the case of discordance between the spouses, subsequent fertility was found to remain intermediate between those agreeing to continue childbirth and those wanting to limit it. The findings also affirmed that child sex preference, specifically son preference, still persists in Indian society. More than 80% of the couples with only daughters in IHDS-I mutually wanted to have additional children, whereas in families that only had sons, the chance of a subsequent pregnancy was inversely associated with the number of sons. Strong patriarchal settings, combined with cultural and socioeconomic factors, affect the persistence of sex preference in India. Programmes aimed at increasing family planning use need to address son preference and should include components that promote the value of girl children.

Development of a novel allele-specific Rfo marker and creation of Ogura CMS fertility-restored interspecific hybrids in Brassica oleracea.

PubMed

Yu, Hai-Long; Fang, Zhi-Yuan; Liu, Yu-Mei; Yang, Li-Mei; Zhuang, Mu; Lv, Hong-Hao; Li, Zhan-Sheng; Han, Feng-Qing; Liu, Xiao-Ping; Zhang, Yang-Yong

2016-08-01

A novel allele-specific Rfo marker was developed and proved to be effective for MAS of Rfo gene in B. oleracea background and six Ogu-CMS fertility-restored interspecific hybrids were created for the first time. Ogura cytoplasmic male sterility (Ogu-CMS) has been extensively used for Brassica oleracea hybrid production. However, because of maternal inheritance, all the hybrids produced by CMS lines are male sterile and cannot be self-pollinated, which prohibits germplasm maintenance and innovation. This problem can be overcome by using the Ogu-CMS restorer line, but restorer material is absent in B. oleracea crops. Here, Rfo, a fertility-restored gene of Ogu-CMS, was transferred from rapeseed restorer lines into a Chinese kale Ogu-CMS line using interspecific hybridization combined with embryo rescue. Nine interspecific, triploid plant progenies were identified at morphological and ploidy level, with phenotypes intermediate between those of rapeseed and Chinese kale. Because the Rfo marker (Hu et al., Mol Breeding 22:663-674, 2008) cannot distinguish the Rfo and its homologies under a B. oleracea background, a novel allele-specific Rfo marker was developed based on the BLAST analysis of highly homologous Rfo sequences in B. oleracea. Screening using the novel Rfo marker found that six interspecific hybrids carrying Rfo were also fertile, although fertility varied during different flowering periods. Furthermore, BC1 offsprings with the Rfo gene were selected with the allele-specific Rfo marker and showed restored fertility. These results indicated that the novel allele-specific marker could be used for the MAS of Rfo gene in B. oleracea, and this study lays the foundation for the development of Ogu-CMS restorer material in cabbage and its related other subspecies.

Utilizing the Experience of Consumers in Consultation to Develop the Australasian Oncofertility Consortium Charter.

PubMed

Anazodo, Antoinette C; Gerstl, Brigitte; Stern, Catharyn J; McLachlan, Robert I; Agresta, Franca; Jayasinghe, Yasmin; Cohn, Richard J; Wakefield, Claire E; Chapman, Michael; Ledger, William; Sullivan, Elizabeth A

2016-09-01

In Australia and New Zealand, there has not been a national systematic development of oncofertility services for cancer patients of reproductive age although many cancer and fertility centers have independently developed services. A number of barriers exist to the development of these services, including a lack of clear referral pathways, a lack of communication between clinicians and patients about fertility preservation, differences in the knowledge base of clinicians about the risk of cancer treatment causing infertility and fertility preservation options, a lack of national health insurance funding covering all aspects of fertility preservation, and storage costs and cultural, religious, and ethical barriers. The development of strategies to overcome these barriers is a high priority for oncofertility care to ensure that equitable access to the best standard of care is available for all patients. The FUTuRE Fertility Research Group led a collaborative consultation process with the Australasian Oncofertility Consumer group and oncofertility specialists to explore consumers' experiences of oncofertility care. Consumers participated in qualitative focus group meetings to define and develop a model of consumer driven or informed "gold standard oncofertility care" with the aim of putting together a Charter that specifically described this. The finalized Australasian Oncofertility Consortium Charter documents eight key elements of gold standard oncofertility care that will be used to monitor the implementation of oncofertility services nationally, to ensure that these key elements are incorporated into standard practice over time.

Internalization of silver nanoparticles into mouse spermatozoa results in poor fertilization and compromised embryo development

PubMed Central

Yoisungnern, Ton; Choi, Yun-Jung; Woong Han, Jae; Kang, Min-Hee; Das, Joydeep; Gurunathan, Sangiliyandi; Kwon, Deug-Nam; Cho, Ssang-Goo; Park, Chankyu; Kyung Chang, Won; Chang, Byung-Soo; Parnpai, Rangsun; Kim, Jin-Hoi

2015-01-01

Silver nanoparticles (AgNPs) have many features that make them attractive as medical devices, especially in therapeutic agents and drug delivery systems. Here we have introduced AgNPs into mouse spermatozoa and then determined the cytotoxic effects of AgNPs on sperm function and subsequent embryo development. Scanning electron microscopy and transmission electron microscopy analyses showed that AgNPs could be internalized into sperm cells. Furthermore, exposure to AgNPs inhibited sperm viability and the acrosome reaction in a dose-dependent manner, whereas sperm mitochondrial copy numbers, morphological abnormalities, and mortality due to reactive oxygen species were significantly increased. Likewise, sperm abnormalities due to AgNPs internalization significantly decreased the rate of oocyte fertilization and blastocyst formation. Blastocysts obtained from AgNPs-treated spermatozoa showed lower expression of trophectoderm-associated and pluripotent marker genes. Overall, we propose that AgNPs internalization into spermatozoa may alter sperm physiology, leading to poor fertilization and embryonic development. Such AgNPs-induced reprotoxicity may be a valuable tool as models for testing the safety and applicability of medical devices using AgNPs. PMID:26054035

Bayesian Inference of Baseline Fertility and Treatment Effects via a Crop Yield-Fertility Model

PubMed Central

Chen, Hungyen; Yamagishi, Junko; Kishino, Hirohisa

2014-01-01

To effectively manage soil fertility, knowledge is needed of how a crop uses nutrients from fertilizer applied to the soil. Soil quality is a combination of biological, chemical and physical properties and is hard to assess directly because of collective and multiple functional effects. In this paper, we focus on the application of these concepts to agriculture. We define the baseline fertility of soil as the level of fertility that a crop can acquire for growth from the soil. With this strict definition, we propose a new crop yield-fertility model that enables quantification of the process of improving baseline fertility and the effects of treatments solely from the time series of crop yields. The model was modified from Michaelis-Menten kinetics and measured the additional effects of the treatments given the baseline fertility. Using more than 30 years of experimental data, we used the Bayesian framework to estimate the improvements in baseline fertility and the effects of fertilizer and farmyard manure (FYM) on maize (Zea mays), barley (Hordeum vulgare), and soybean (Glycine max) yields. Fertilizer contributed the most to the barley yield and FYM contributed the most to the soybean yield among the three crops. The baseline fertility of the subsurface soil was very low for maize and barley prior to fertilization. In contrast, the baseline fertility in this soil approximated half-saturated fertility for the soybean crop. The long-term soil fertility was increased by adding FYM, but the effect of FYM addition was reduced by the addition of fertilizer. Our results provide evidence that long-term soil fertility under continuous farming was maintained, or increased, by the application of natural nutrients compared with the application of synthetic fertilizer. PMID:25405353

Development master arm of 2-DOF planar parallel manipulator for In-Vitro Fertilization

NASA Astrophysics Data System (ADS)

Thamrongaphichartkul, Kitti; Vongbunyong, Supachai; Nuntakarn, Lalana

2018-01-01

Micromanipulator is a mechanical device used for manipulating miniature objects in the order of micron. It is widely used in In-Vitro Fertilization (IVF) in which sperms will be held in a micro-needle and penetrate to an oocyte for fertilization. IVF needs to be performed by high skill embryologists to control the movement of the needle accurately due to the lack of tactile perception of the user. Haptic device is a device that can transmit and simulate position, velocity and force in order to enhance interaction between the user and system. However, commercially available haptic devices have unnecessary degrees of freedom and limited workspace which are inappropriate for IVF process. This paper focuses on development of a haptic device for using in IVF process. It will be used as a master arm for the master-slave system for IVF process in order to enhance the ability of users to control the micromanipulator. As a result, the embryologist is able to carry out the IVF process more effectively with having tactile perception.

Effect of nitrogen fertilization and fungicides on Botryosphaeria stem blight lesion development on detached blueberry stems

USDA-ARS?s Scientific Manuscript database

Botryosphaeria stem blight is a destructive disease of blueberries. Field observations indicate stem blight is more severe on vigorous plants than on slower growing plants. Two studies compared the effect of two types of fertilizers applied at four rates and nine fungicides on lesion development fo...

The impact of war, famine, and economic decline on marital fertility in Ethiopia.

PubMed

Lindstrom, D P; Berhanu, B

1999-05-01

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.

Achieving fertility control through woman’s autonomy and access to maternal healthcare: Are we on track? In-depth analysis of PDHS-2012-13

PubMed Central

Hassan, Sehar-un-Nisa; Siddiqui, Salma; Mahmood, Ayeshah

2015-01-01

Background and Objective: Fertility control preferences and maternal healthcare have recently become a major concern for developing nations with evidence suggesting that low fertility control rates and poor maternal healthcare are among major obstructions in ensuring health and social status for women. Our objective was toanalyze the factors that influence women’s autonomy, access to maternal healthcare, and fertility control preferences in Pakistan. Methods: Data consisted of 11,761 ever-married women of ages 15-49 years from PDHS, 2012-13. Variables included socio-demographics, women’s autonomy, fertility control preferences and access to maternal healthcare. Results: Findings from multivariate analysis showed that women’s younger age, having less than three number of children and independent or joint decision-making (indicators of high autonomy) remained the most significant predictors for access to better quality maternal healthcare and better fertility control preferences when other variables were controlled. Conclusion: Women’s access to good quality maternal health care and fertility control preferences are directly and indirectly influenced by their demographic characteristics and decision-making patterns in domestic affairs. PMID:26870096

Fertility, Human Capital, and Economic Growth over the Demographic Transition

PubMed Central

Mason, Andrew

2009-01-01

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

Fertility Intentions, Career Considerations and Subsequent Births: The Moderating Effects of Women’s Work Hours

PubMed Central

Johnson, David R.

2014-01-01

Prior research indicates a negative relationship between women’s labor force participation and fertility at the individual level in the United States, but little is known about the reasons for this relationship beyond work hours. We employed discrete event history models using panel data from the National Survey of Families and Households (N = 2,411) and found that the importance of career considerations mediates the work hours/fertility relationship. Further, fertility intentions and the importance of career considerations were more predictive of birth outcomes as women’s work hours increase. Ultimately, our findings challenge the assumption that working more hours is the direct cause for employed women having fewer children and highlight the importance of career and fertility preferences in fertility outcomes. PMID:25506189

Female gametophyte development and double fertilization in Balsas teosinte, Zea mays subsp. parviglumis (Poaceae).

PubMed

Wu, Chi-Chih; Diggle, Pamela K; Friedman, William E

2011-09-01

Over the course of maize evolution, domestication played a major role in the structural transition of the vegetative and reproductive characteristics that distinguish it from its closest wild relative, Zea mays subsp. parviglumis (Balsas teosinte). Little is known, however, about impacts of the domestication process on the cellular features of the female gametophyte and the subsequent reproductive events after fertilization, even though they are essential components of plant sexual reproduction. In this study, we investigated the developmental and cellular features of the Balsas teosinte female gametophyte and early developing seed in order to unravel the key structural and evolutionary transitions of the reproductive process associated with the domestication of the ancestor of maize. Our results show that the female gametophyte of Balsas teosinte is a variation of the Polygonum type with proliferative antipodal cells and is similar to that of maize. The fertilization process of Balsas teosinte also is basically similar to domesticated maize. In contrast to maize, many events associated with the development of the embryo and endosperm appear to be initiated earlier in Balsas teosinte. Our study suggests that the pattern of female gametophyte development with antipodal proliferation is common among species and subspecies of Zea and evolved before maize domestication. In addition, we propose that the relatively longer duration of the free nuclear endosperm phase in maize is correlated with the development of a larger fruit (kernel or caryopsis) and with a bigger endosperm compared with Balsas teosinte.

Temperature, but not pH, compromises sea urchin fertilization and early development under near-future climate change scenarios.

PubMed

Byrne, Maria; Ho, Melanie; Selvakumaraswamy, Paulina; Nguyen, Hong D; Dworjanyn, Symon A; Davis, Andy R

2009-05-22

Global warming is causing ocean warming and acidification. The distribution of Heliocidaris erythrogramma coincides with the eastern Australia climate change hot spot, where disproportionate warming makes marine biota particularly vulnerable to climate change. In keeping with near-future climate change scenarios, we determined the interactive effects of warming and acidification on fertilization and development of this echinoid. Experimental treatments (20-26 degrees C, pH 7.6-8.2) were tested in all combinations for the 'business-as-usual' scenario, with 20 degrees C/pH 8.2 being ambient. Percentage of fertilization was high (>89%) across all treatments. There was no difference in percentage of normal development in any pH treatment. In elevated temperature conditions, +4 degrees C reduced cleavage by 40 per cent and +6 degrees C by a further 20 per cent. Normal gastrulation fell below 4 per cent at +6 degrees C. At 26 degrees C, development was impaired. As the first study of interactive effects of temperature and pH on sea urchin development, we confirm the thermotolerance and pH resilience of fertilization and embryogenesis within predicted climate change scenarios, with negative effects at upper limits of ocean warming. Our findings place single stressor studies in context and emphasize the need for experiments that address ocean warming and acidification concurrently. Although ocean acidification research has focused on impaired calcification, embryos may not reach the skeletogenic stage in a warm ocean.

Semen collection and fertility in naturally fertile sandhill cranes

USGS Publications Warehouse

Chen, G.; Gee, G.F.; Nicolich, Jane M.; Taylor, J.A.; Urbanek, R.P.; Stahlecker, D.W.

1997-01-01

Aviculturists often ask if semen collection will interfere with fertility in naturally fertile pairs of cranes. We used 12 naturally fertile Florida sandhill crane (Grus canadensis pratensis) pairs for this study, 6 control and 6 experimental. All pairs had produced fertile eggs in previous years and were in out-of-doors pens scattered throughout different pen complexes, within auditory range but physically isolated. Semen was collected on Tuesday mornings and Friday afternoons from 26 February 1993 to 4 June 1993. We used standard artificial insemination methods to collect and to evaluate the semen and spermatozoa. Semen collection did not affect semen quality or quantity. Semen volume, sperm density, sperm motility, sperm morphology, sperm live, sperm number per collection, and male response to semen collection exhibited significant daily variation (P < 0.05). Although semen collection began 13 days before the first egg in the experimental group, we observed no differences in the date of first egg laid or in fertility between experimental and control groups. Also, we observed no differences in the interval between clutches or in the percentage of broken eggs between experimental and control groups. Sires consistently producing better semen samples produced fewer fertile eggs than sires producing poorer semen samples (r = 0.60).

Socioeconomic status and fertility intentions among Chinese women with one child.

PubMed

Zheng, Yumei; Yuan, Jingqin; Xu, Tan; Chen, Mei; Liang, Hui; Connor, Donovan; Gao, Yongqing; Sun, Wenjie; Shankar, Nivedita; Lu, Chuanwen; Jiang, Yan

2016-04-01

There has been a lack of socioeconomic status (SES) disparity analysis on women in China with only one child, the family planning target population. In 2008, the National Research Institute for Family Planning of China conducted a study investigating the relationship between SES and fertility intentions among 17,093 women in China who already had one child. A questionnaire was used to collect information on SES and fertility intentions, and logistic regression models were used to estimate the odds ratios and 95% CIs of fertility intentions according to SES. Compared with female farmers, women in other occupations intended to have fewer children (p < 0.05). Additionally, compared with women with low educational level (illiterate/primary), women with secondary and postsecondary education intended to have fewer children (p < 0.05) (OR = 0.70; 95% CI: 0.61-0.81 and OR = 0.56; 95% CI 0.47-0.66). A mother's education level was significantly and negatively associated with fertility intentions after adjustment for potential confounders (p < 0.05). Among Chinese women who had one child, the women with higher SES (e.g. higher educational level) had lower fertility intentions. There is an SES disparity in the fertility intention among Chinese women who already have one child. China's policy-makers should consider increasing high SES women's fertility intention.

Uterine influences on conceptus development in fertility-classified heifers

USDA-ARS?s Scientific Manuscript database

A major unresolved issue is how the uterus influences infertility and subfertility in cattle. Serial embryo transfer was previously used to classify heifers as high fertile (HF), subfertile (SF), or infertile (IF). To assess pregnancy loss in those animals, two in vivo produced embryos were transfer...

Fact Sheet - Phosphate Fertilizer Production Plants and Phosphoric Acid Manufacturing Plants NESHAP

EPA Pesticide Factsheets

Fact sheet summarizing National Emission Standards for Hazardous Air Pollutants (NESHAP) for Phosphate Fertilizer Production Plants and Phosphoric Acid Manufacturing Plants (40 CFR 63 Subparts AA and BB).

THE FERTILITY MOTIVATIONS OF YOUTH PREDICT LATER FERTILITY OUTCOMES: A PROSPECTIVE ANALYSIS OF NLSY DATA*

PubMed Central

Miller, Warren B.; Rodgers, Joseph Lee; Pasta, David J.

2010-01-01

We examine how the motivational sequence that leads to childbearing predicts fertility outcomes across reproductive careers. Using a motivational traits-desires-intentions theoretical framework, we test a structural equation model using prospective male and female data from the National Longitudinal Survey of Youth. Specifically, we take motivational data collected during the 1979–1982 period, when the youths were in their teens and early twenties, to predict the timing of the next child born after 1982 and the total number of children born by 2002. Separate models were estimated for males and females but with equality constraints imposed unless relaxing these constraints improved the overall model fit. The results indicate substantial explanatory power of fertility motivations for both short-term and long-term fertility outcomes. They also reveal the effects of both gender role attitude and educational intentions on these outcomes. Although some sex differences in model pathways occurred, the primary hypothesized pathways were essentially the same across the sexes. Two validity substudies support the soundness of the results. A third substudy comparing the male and female models across the sample split on the basis of previous childbearing revealed a number of pattern differences within the four sex-by-previous childbearing groups. Several of the more robust of these pattern differences offer interesting insights and support the validity and usefulness of our theoretical framework. PMID:20463915

33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

Code of Federal Regulations, 2010 CFR

2010-07-01

... nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126..., ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. (a) When any item of ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

Code of Federal Regulations, 2014 CFR

2014-07-01

... nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126..., ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. (a) When any item of ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

Code of Federal Regulations, 2013 CFR

2013-07-01

... nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126..., ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. (a) When any item of ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

Code of Federal Regulations, 2011 CFR

2011-07-01

... nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126..., ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. (a) When any item of ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

33 CFR 126.28 - Ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

Code of Federal Regulations, 2012 CFR

2012-07-01

... nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. 126.28 Section 126..., ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate; general provisions. (a) When any item of ammonium nitrate, ammonium nitrate fertilizers, fertilizer mixtures, or nitro carbo nitrate...

Jordan's 2002 to 2012 Fertility Stall and Parallel USAID Investments in Family Planning: Lessons From an Assessment to Guide Future Programming

PubMed Central

Spindler, Esther; Bitar, Nisreen; Solo, Julie; Menstell, Elizabeth; Shattuck, Dominick

2017-01-01

Health practitioners, researchers, and donors are stumped about Jordan's stalled fertility rate, which has stagnated between 3.7 and 3.5 children per woman from 2002 to 2012, above the national replacement level of 2.1. This stall paralleled United States Agency for International Development (USAID) funding investments in family planning in Jordan, triggering an assessment of USAID family planning programming in Jordan. This article describes the methods, results, and implications of the programmatic assessment. Methods included an extensive desk review of USAID programs in Jordan and 69 interviews with reproductive health stakeholders. We explored reasons for fertility stagnation in Jordan's total fertility rate (TFR) and assessed the effects of USAID programming on family planning outcomes over the same time period. The assessment results suggest that the increased use of less effective methods, in particular withdrawal and condoms, are contributing to Jordan's TFR stall. Jordan's limited method mix, combined with strong sociocultural determinants around reproduction and fertility desires, have contributed to low contraceptive effectiveness in Jordan. Over the same time period, USAID contributions toward increasing family planning access and use, largely focused on service delivery programs, were extensive. Examples of effective initiatives, among others, include task shifting of IUD insertion services to midwives due to a shortage of female physicians. However, key challenges to improved use of family planning services include limited government investments in family planning programs, influential service provider behaviors and biases that limit informed counseling and choice, pervasive strong social norms of family size and fertility, and limited availability of different contraceptive methods. In contexts where sociocultural norms and a limited method mix are the dominant barriers toward improved family planning use, increased national government investments

Fertility reduction policies and poverty in Third World countries: ethical issues.

PubMed

Hernandez, D J

1985-01-01

This article begins with a discussion of the motivation for fertility reduction and related population policies. Next, it identifies the two major approaches to evaluating these policies in the population ethics literature: the individualistic approach and the international approach. Each approach is then characterized according to the kinds of policies evaluated, the ethical principles that are most prominent, and the major conclusions drawn. Major empirical gaps in the population ethics literature are identified, and pertinent social science issues concerning the effectiveness of family planning programs, the socioeconomic determinants of fertility, and the interpersonal or community determinants of fertility are discussed. Finally, these issues are linked with the United Nations World Population Plan of Action to identify ethical questions that warrant detailed scrutiny.

Centennial of Alabama's cullars rotation, the south’s oldest, continuous, soil fertility experiment

USDA-ARS?s Scientific Manuscript database

Alabama’s “Cullars Rotation” experiment (circa 1911) was placed on the National Register of Historical Places as the oldest, continuous, soil fertility experiment in the South in 2003. Along with its nearby predecessor on the National Register, “The Old Rotation” (circa 1896), these experiments con...

Flower thermoregulation facilitates fertilization in Asian sacred lotus

PubMed Central

Li, Jiao-Kun; Huang, Shuang-Quan

2009-01-01

Background and Aims The thermoregulatory flower of the Asian sacred lotus (Nelumbo nucifera) can maintain a relatively stable temperature despite great variations in ambient temperature during anthesis. The thermoregulation has been hypothesized to offer a direct energy reward for pollinators in lotus flowers. This study aims to examine whether the stable temperature maintained in the floral chamber influences the fertilization process and seed development. Methods An artificial refrigeration instrument was employed to cool flowers during the fertilization process and post-fertilization period in an experimental population. The effect of temperature on post-pollination events was also examined by removing petals in two field populations. Key Results Treatments with low floral temperature did not reduce stigma receptivity or pollen viability in undehisced anthers. Low temperature during the fertilization period significantly decreased seed set per flower but low temperature during the phase of seed development had no effect, suggesting that temperature regulation by lotus flowers facilitated fertilization success. Hand-pollination treatments in two field populations indicated that seed set of flowers with petals removed was lower than that of intact flowers in north China, where ambient temperatures are low, but not in south China, confirming that reducing the temperature of carpels did influence post-pollination events. Conclusions The experiments suggest that floral thermoregulation in lotus could enhance female reproductive success by facilitating fertilization. PMID:19282320

Impact of inflammation on male fertility.

PubMed

Sarkar, Oli; Bahrainwala, Jamila; Chandrasekaran, Sambamurthy; Kothari, Shiva; Mathur, Premendu P; Agarwal, Ashok

2011-01-01

The male uro-genital tract is susceptible to gram-negative bacterial infections that produce a state of inflammation, particularly in the testis and epididymis. Development of germline stem cells into motile spermatozoa takes place in these organs and thus any impairment therein has a direct effect on male fertility. A number of factors are known to impair male fertility including environmental and chemical factors, lifestyle, and infections. The last is a little-known and poorly understood cause of male sub-/infertility. The presence of the pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF- alpha), interleukin-1alpha (IL-1alpha) and interleukin-1beta (IL-1beta) in the male uro-genital tract following bacterial infections suggests that such infections could have cytokine-mediated anti-fertility effects. Furthermore, inflammation has been associated with elevated levels of reactive oxygen species and oxidative stress both of which affect male fertility. The present article summarizes the effects of inflammation on the testis, epididymis and spermatozoa. We review the correlations between inflammation and oxidative stress vis-à-vis spermatogenesis and discuss the implications of infections on male fertility/infertility and assisted reproductive technologies for the male.

Developing a post-treatment survivorship care plan to help breast cancer survivors understand their fertility.

PubMed

Gorman, Jessica R; Julian, Anne K; Roberts, Samantha A; Romero, Sally A D; Ehren, Jennifer L; Krychman, Michael L; Boles, Sarah G; Mao, Jun; Irene Su, H

2018-02-01

Reproductive-aged breast cancer survivors (BCS) who have completed initial cancer treatment frequently want to know about their future fertility potential. The purpose of this qualitative study was to assess if the fertility-related content presented in the survivorship care plan prototype met the informational needs of post-treatment BCS and to provide an opportunity for the target audience to review and react to the proposed content and design. We conducted and analyzed transcripts from seven focus groups with BCS to evaluate their reactions to the survivorship care plan prototype. We independently coded transcripts for consistent themes and sub-themes and used a consensus-building approach to agree on interpretation of results. We identified five themes that describe the post-treatment BCS' responses to the prototype survivorship care plan in the context of their informational needs and experiences: (1) the prototype's fertility-related information is relevant; (2) desire for clinical parameters to help survivors understand their infertility risk; (3) fertility-related information is important throughout survivorship; (4) evidence-based content from a neutral source is trustworthy; and (5) the recommendation to see a fertility specialist is helpful, but cost is a barrier. BCS have concerns and needs related to their fertility potential after initial breast cancer treatment. The evidence-based information offered in our prototype survivorship care plan was acceptable to BCS and has significant potential to address these needs. Additional primary data that identify post-cancer treatment indicators of fertility would advance this effort.

Female labour force participation and fertility.

PubMed

Concepcion, M B

1974-01-01

The levels of labor force participation by women in selected Asian countries were recorded in a series of censuses taken over a period of years. These levels were less influenced than male employment levels by economic conditions and more influenced by cultural traits of the country. Postwar trends seem to have fallen in Korea, risen in Singapore and the Philippines, and remained steady in Japan, Malaya, and Thailand. The limitations of these data are mentioned. In Thailand and West Malaysia greater percentages of women worked in agricultural than non-agricultural employment; in the Philippines, where women did not work so much in agricultural pursuits, their jobs were still in traditional rather than in development industries. In the cities of Bangkok, Manila, and Kuala Lumpur, fertility was lower for working than for non-working women. In rural agricultural areas, the fertility of working women was minimally higher, probably due to economic need of lar ger families. It is concluded that urban life separates the employment and the family roles of working women, leading to lowered fertility; this does not occur in rural areas. The creation of new roles for women alternative or supplementary to marriage and motherhood would result in lowered fertility. In high fertility Asian countries, policies directed toward greater participation of women in non-agricultural work and great er exposure to an urban lifestyle might achieve fertility reductions.

Emissions of N2O and NO from fertilized fields: Summary of available measurement data

NASA Astrophysics Data System (ADS)

Bouwman, A. F.; Boumans, L. J. M.; Batjes, N. H.

2002-12-01

Information from 846 N2O emission measurements in agricultural fields and 99 measurements for NO emissions was summarized to assess the influence of various factors regulating emissions from mineral soils. The data indicate that there is a strong increase of both N2O and NO emissions accompanying N application rates, and soils with high organic-C content show higher emissions than less fertile soils. A fine soil texture, restricted drainage, and neutral to slightly acidic conditions favor N2O emission, while (though not significant) a good soil drainage, coarse texture, and neutral soil reaction favor NO emission. Fertilizer type and crop type are important factors for N2O but not for NO, while the fertilizer application mode has a significant influence on NO only. Regarding the measurements, longer measurement periods yield more of the fertilization effect on N2O and NO emissions, and intensive measurements (≥1 per day) yield lower emissions than less intensive measurements (2-3 per week). The available data can be used to develop simple models based on the major regulating factors which describe the spatial variability of emissions of N2O and NO with less uncertainty than emission factor approaches based on country N inputs, as currently used in national emission inventories.

Development of a new fertility prediction model for stallion semen, including flow cytometry.

PubMed

Barrier Battut, I; Kempfer, A; Becker, J; Lebailly, L; Camugli, S; Chevrier, L

2016-09-01

Several laboratories routinely use flow cytometry to evaluate stallion semen quality. However, objective and practical tools for the on-field interpretation of data concerning fertilizing potential are scarce. A panel of nine tests, evaluating a large number of compartments or functions of the spermatozoa: motility, morphology, viability, mitochondrial activity, oxidation level, acrosome integrity, DNA integrity, "organization" of the plasma membrane, and hypoosmotic resistance, was applied to a population of 43 stallions, 33 of which showing widely differing fertilities (19%-84% pregnancy rate per cycle [PRC]). Analyses were performed either within 2 hours after semen collection or after 24-hour storage at 4 °C in INRA96 extender, on three to six ejaculates for each stallion. The aim was to provide data on the distribution of values among said population, showing within-stallion and between-stallion variability, and to determine whether appropriate combinations of tests could evaluate the fertilizing potential of each stallion. Within-stallion repeatability, defined as intrastallion correlation (r = between-stallion variance/total variance) ranged between 0.29 and 0.84 for "conventional" variables (viability, morphology, and motility), and between 0.15 and 0.81 for "cytometric" variables. Those data suggested that analyzing six ejaculates would be adequate to characterize a stallion. For most variables, except those related to DNA integrity and some motility variables, results differed significantly between immediately performed analyses and analyses performed after 24 hours at 4 °C. Two "best-fit" combinations of variables were determined. Factorial discriminant analysis using a first combination of seven variables, including the polarization of mitochondria, acrosome integrity, DNA integrity, and hypoosmotic resistance, permitted exact determination of the fertility group for each stallion: fertile, that is, PRC higher than 55%; intermediate, that is, 45

Fertility trends in Singapore.

PubMed

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

1988-10-01

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

FGF signaling supports Drosophila fertility by regulating development of ovarian muscle tissues

PubMed Central

Irizarry, Jihyun; Stathopoulos, Angelike

2015-01-01

The thisbe (ths) gene encodes a Drosophila fibroblast growth factor (FGF), and mutant females are viable but sterile suggesting a link between FGF signaling and fertility. Ovaries exhibit abnormal morphology including lack of epithelial sheaths, muscle tissues that surround ovarioles. Here we investigated how FGF influences Drosophila ovary morphogenesis and identified several roles. Heartless (Htl) FGF receptor was found expressed within somatic cells at the larval and pupal stages, and phenotypes were uncovered using RNAi. Differentiation of terminal filament cells was affected, but this effect did not alter ovariole number. In addition, proliferation of epithelial sheath progenitors, the apical cells, was decreased in both htl and ths mutants, while ectopic expression of the Ths ligand led to these cells’ over-proliferation suggesting that FGF signaling supports ovarian muscle sheath formation by controlling apical cell number in the developing gonad. Additionally, live imaging of adult ovaries was used to show that htl RNAi mutants, hypomorphic mutants in which epithelial sheaths are present, exhibit abnormal muscle contractions. Collectively, our results demonstrate that proper formation of ovarian muscle tissues is regulated by FGF signaling in the larval and pupal stages through control of apical cell proliferation and is required to support fertility. PMID:25958090

Effect of sericin supplementation during in vitro maturation on the maturation, fertilization and development of porcine oocytes.

PubMed

Do, L T K; Namula, Z; Luu, V V; Sato, Y; Taniguchi, M; Isobe, T; Kikuchi, K; Otoi, T

2014-04-01

This study aimed to examine the effects of sericin supplementation during in vitro oocyte maturation on the nuclear maturation, fertilization and development of porcine oocytes. Cumulus-oocyte complexes (COCs) were cultured in maturation medium supplemented with 0 (control), 0.1, 0.5, 1.0, 2.5 or 5.0% sericin and were then subjected to in vitro fertilization and embryo culture. More COCs matured with 1.0% sericin underwent germinal vesicle breakdown and reached metaphase II compared with the control COCs matured without sericin (p < 0.01). The proportions of oocytes with DNA-fragmented nuclei did not differ between the groups, regardless of the sericin level. The total fertilization rate of oocytes matured with 1.0% sericin was higher (p < 0.05) than that of oocytes matured with 0.1%, 2.5% and 5.0% sericin. Supplementation with more than 1.0% sericin decreased the DNA fragmentation index of the blastocysts compared with the control group (p < 0.05). However, the supplementation of the maturation medium with sericin had no beneficial effects on the cleavage, development to the blastocyst stage and the total cell number of the embryos. Our findings indicate that supplementation with 1.0% sericin during maturation culture may improve the nuclear maturation and the quality of the embryos but does not affect blastocyst formation. © 2014 Blackwell Verlag GmbH.

Assessment of expected breeding values for fertility traits of Murrah buffaloes under subtropical climate.

PubMed

Dash, Soumya; Chakravarty, A K; Singh, Avtar; Shivahre, Pushp Raj; Upadhyay, Arpan; Sah, Vaishali; Singh, K Mahesh

2015-03-01

The aim of the present study was to assess the influence of temperature and humidity prevalent under subtropical climate on the breeding values for fertility traits viz. service period (SP), pregnancy rate (PR) and conception rate (CR) of Murrah buffaloes in National Dairy Research Institute (NDRI) herd. Fertility data on 1379 records of 581 Murrah buffaloes spread over four lactations and climatic parameters viz. dry bulb temperature and relative humidity (RH) spanned over 20 years (1993-2012) were collected from NDRI and Central Soil and Salinity Research Institute, Karnal, India. Monthly average temperature humidity index (THI) values were estimated. Threshold THI value affecting fertility traits was identified by fixed least-squares model analysis. Three zones of non-heat stress, heat stress and critical heat stress zones were developed in a year. The genetic parameters heritability (h(2)) and repeatability (r) of each fertility trait were estimated. Genetic evaluation of Murrah buffaloes was performed in each zone with respect to their expected breeding values (EBV) for fertility traits. Effect of THI was found significant (p<0.001) on all fertility traits with threshold THI value identified as 75. Based on THI values, a year was classified into three zones: Non heat stress zone(THI 56.71-73.21), HSZ (THI 75.39-81.60) and critical HSZ (THI 80.27-81.60). The EBVfor SP, PR, CR were estimated as 138.57 days, 0.362 and 69.02% in non-HSZ while in HSZ EBV were found as 139.62 days, 0.358 and 68.81%, respectively. EBV for SP was increased to 140.92 days and for PR and CR, it was declined to 0.357 and 68.71% in critical HSZ. The negative effect of THI was observed on EBV of fertility traits under the non-HSZ and critical HSZ Thus, the influence of THI should be adjusted before estimating the breeding values for fertility traits in Murrah buffaloes.

Practices, perceptions, and implications of fertilizer use in East-Central China.

PubMed

Yang, Xiaoying; Fang, Shubo

2015-11-01

Face-to-face interviews (n = 553) were conducted in five counties in East-Central China to study farmers' fertilizer application behaviors, decision-making processes, attitudes towards adopting better fertilizer application technologies, and environmental consciousness. The survey results revealed widespread fertilizer misapplication and highly variable application behaviors in the study regions. The lack of scientific knowledge on fertilizers and the absence of guidance from agricultural extension services have forced the farmers to rely on personal judgment and advice from fertilizer dealers and friends to make decisions in fertilizer application. Overall, farmers have been idiosyncratic in fertilizer application with limited adoption of better fertilizer application technologies. There are great potentials for reducing pollutant load from agricultural runoff through promoting scientific fertilizer application in the regions. However, farmers' diverse preferences over agricultural extension programs necessitate an integrated approach emphasizing farmer involvement throughout the development of such programs for promoting better fertilizer application practices.

Effect of in-utero diethylstilboestrol exposure on human oocyte quality and fertilization in a programme of in-vitro fertilization.

PubMed

Kerjean, A; Poirot, C; Epelboin, S; Jouannet, P

1999-06-01

Genital tract abnormalities and adverse pregnancy outcome are well known in women exposed in utero to diethylstilboestrol (DES). Data about adverse reproductive performance in women exposed to DES have been published, including controversial reports of menstrual dysfunction, poor responses after ovarian stimulation, oocyte maturation and fertilization abnormalities. We compared oocyte quality, in-vitro fertilization results and embryo quality for women exposed in utero to DES with a control group. Between 1989 and 1996, 56 DES-exposed women who had 125 in-vitro fertilization (IVF) attempts were retrospectively compared to a control group of 45 women with tubal disease, who underwent 73 IVF attempts. Couples suffering from male infertility were excluded. The parameters compared were oocyte quality (maturation abnormalities, immature oocyte, mature oocyte), fertilization and cleavage rate (per treated and metaphase II oocytes), and embryo quality (number and grade). We found no significant difference in oocyte maturational status, fertilization rates, cleavage rates, embryo quality and development between DES-exposed subjects and control subjects. These results suggest that in-utero exposure to DES has no significant influence on oocyte quality and fertilization ability as judged during IVF attempts.

Embryo yield after in vitro fertilization in women undergoing embryo banking for fertility preservation before chemotherapy.

PubMed

Robertson, Audra D; Missmer, Stacey A; Ginsburg, Elizabeth S

2011-02-01

To evaluate embryo yield after IVF in patients undergoing embryo banking before chemotherapy. A retrospective cohort study. Hospital-based academic medical center. Thirty-eight women diagnosed with cancer or autoimmune disease presenting for IVF cycles, with or without intracytoplasmic sperm injection (ICSI), for embryo cryopreservation before any therapy were compared with 921 presumably fertile women undergoing IVF for male factor infertility from January 2001 through October 2007. Standard IVF or ICSI protocol, embryo freezing, and ET. The number of 2 pronuclear (2PN) embryos created and suitable for cryopreservation or transfer. No statistically significant differences were observed between preservation and male factor groups for number of embryos, number of oocytes, or amount of gonadotropin needed to stimulate follicular development. Peak serum E(2) levels were significantly lower for women with disease-seeking fertility preservation. Women facing chemotherapy as treatment for cancer or systemic autoimmune disease infrequently undergo fertility preservation. If offered this potentially fertility-preserving option, these data suggest equivalent embryo yield compared with women with infertile male partners. Our data report no significant complications in subsequent births in those who sought fertility preservation, which is informative and encouraging for these women and their providers. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Utilization of third-party in vitro fertilization in the United States.

PubMed

Kushnir, Vitaly A; Darmon, Sarah K; Shapiro, Alice J; Albertini, David F; Barad, David H; Gleicher, Norbert

2017-03-01

The use of in vitro fertilization that includes third-party in vitro fertilization is increasing. However, the relative contribution of third-party in vitro fertilization that includes the use of donor oocytes, sperm, or embryo and a gestational carrier to the birth cohort after in vitro fertilization is unknown. The purpose of this study was to examine the contribution of third-party in vitro fertilization to the in vitro fertilization birth cohort over the past decade. This retrospective analysis investigated 1,349,874 in vitro fertilization cycles that resulted in 421,525 live births and 549,367 liveborn infants in the United States from 2004-2013. Cycles were self-reported by fertility centers to a national registry: Society for Assisted Reproductive Technologies Clinic Outcome Reporting System. Third-party in vitro fertilization accounted for 217,030 (16.1%) of all in vitro fertilization cycles, 86,063 (20.4%) of all live births, and 115,024 (20.9%) of all liveborn infants. Overall, 39.7% of third-party in vitro fertilization cycles resulted in a live birth, compared with 29.6% of autologous in vitro fertilization cycles. Use of third-party in vitro fertilization increased with maternal age and accounted for 42.2% of all in vitro fertilization cycles and 75.3% of all liveborn infants among women >40 years old. Oocyte donation was the most common third-party in vitro fertilization technique, followed by sperm donation. Over the study period, annual cycle volume and live birth rates gradually increased for both autologous in vitro fertilization and third-party in vitro fertilization (P<.0001 for all). Live birth rates were the highest when multiple third-party in vitro fertilization modalities were used, followed by oocyte donation. Third-party in vitro fertilization use and efficacy have increased over the past decade, now comprising >20% of the total in vitro fertilization birth cohort. In women who are >40 years old, third-party in

FERTILITY INTENTIONS AND EARLY LIFE HEALTH STRESS AMONG WOMEN IN EIGHT INDIAN CITIES: TESTING THE REPRODUCTIVE ACCELERATION HYPOTHESIS.

PubMed

Kulathinal, Sangita; Säävälä, Minna

2015-09-01

In life history theory, early life adversity is associated with an accelerated reproductive tempo. In harsh and unpredictable conditions in developing societies fertility is generally higher and the reproductive tempo faster than in more secure environments. This paper examines whether differences in female anthropometry, particularly adult height, are associated with fertility intentions of women in urban environments in India. The study population consists of women aged 15-29 (N=4485) in slums and non-slums of eight Indian cities in the National Family Health Survey (NFHS) of 2005-2006. Adult height is taken as a proxy for early childhood health and nutritional condition. Fertility intentions are examined by using two variables: the desire to have a child or another child, and to have it relatively soon, as indicative of accelerated reproductive scheduling. Evidence supporting the acceleration hypothesis is found in two urban frames out of 26 examined in a two-staged multinomial logistic model. In three cases, the relationship between fertility intentions and height is the opposite than expected by the acceleration hypothesis: taller women have a higher predictive probability of desiring a(nother) child and/or narrower birth spacing. Potential explanations for the partly contradictory relationship between the childhood health indicator and fertility intentions are discussed.

Recent Fertility Change Among High Fertility Minorities in the United States.

ERIC Educational Resources Information Center

Sweet, James A.

Trends and differentials in fertility for three high fertility minority populations -- Southern rural blacks, Spanish surnamed, and American Indians -- are examined for the intervals between 1957-60 and 1967-70. Fertility levels and patterns of differentials within these three minority populations are also compared with those of the urban white…

Estimates of fertility in Bangladesh.

PubMed

D'souza, S; Rahman, S

1978-01-01

The attempt is made to estimate fertility levels in Bangladesh on the basis of data collected during the 1974 Census. In the 1st section attention is directed to providing an overall picture of the demographic situation in the country. Comparisons between the 1961 and 1974 data demonstrates that the 1974 Census data provide consistent results. Factors such as the degree of urbanization, literacy and economic participation rates--considered as indicators of development--all seem to show little progress during the intercensal period. The use of child/women ratios (CWRs) provides plausible evidence of the likelihood of a fertility decline. A decline in CWR values is small for "all areas" but a marked decline can be noted for "urban areas." The recorded mean number of children is less in 1974 than in 1961 for women under age 35 whereas for the older groups the 1974 Census shows higher mean numbers. The Bangladesh Fertility Survey (BFS) data result for the total fertility rate of 6.58 is very close to that estimated for the 1974 Census--6.59. The reverse survival method also indicates that birthrates have been lower during the 1969-1974 period.

Kinship and the decline of fertility.

PubMed

Zhou, Y

1996-01-01

China's family planning and population control policies, together with the move toward a more market-oriented economy since the 1980s, have led to significant change in people's reproductive values and behavior and a substantial decline in fertility. Traditional kinship in China, its terminology, and the impact of fertility decline on kinship in China and Chinese society are discussed. The decline in fertility is affecting or will affect China's kinship system, the corresponding pattern of terminology, and the social structure. In the more market-oriented economy which has been developing in China, the simplification of the kinship system will help change the structure of Chinese society and weaken the traditional patriarchal culture. A more individualized, contractualized social structure and relationships will result.

Fertilizer Use and Water Quality.

ERIC Educational Resources Information Center

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…

Fertilizing growth: Agricultural inputs and their effects in economic development.

PubMed

McArthur, John W; McCord, Gordon C

2017-07-01

This paper estimates the role of agronomic inputs in cereal yield improvements and the consequences for countries' processes of structural change. The results suggest a clear role for fertilizer, modern seeds and water in boosting yields. We then test for respective empirical links between agricultural yields and economic growth, labor share in agriculture and non-agricultural value added per worker. The identification strategy includes a novel instrumental variable that exploits the unique economic geography of fertilizer production and transport costs to countries' agricultural heartlands. We estimate that a half ton increase in staple yields generates a 14 to 19 percent higher GDP per capita and a 4.6 to 5.6 percentage point lower labor share in agriculture five years later. The results suggest a strong role for agricultural productivity as a driver of structural change.

The Role of SPRASA in Female Fertility

PubMed Central

Wagner, Angela; Tong, Mancy; Shelling, Andrew N.; Chamley, Lawrence W.

2014-01-01

Fertility is a complex process and infertility can have many causes. Sperm protein reactive with antisperm antibody (SPRASA)/sperm lysozyme-like protein 1 is a protein discovered as the target of autoantibodies in infertile men and previously thought to be expressed only in sperm. Using a bovine in vitro fertilization model, we have shown that SPRASA antiserum reduced sperm binding to zona-free oocytes and the development of embryos to morulae but did not affect the postfertilization cleavage rate to 2 cells or sperm motility. We demonstrated that SPRASA was expressed in ovarian follicles, corpora lutea, and oocytes by a combination of reverse transcription-polymerase chain reaction and immunohistochemistry. Female mice immunized with SPRASA had profound infertility following timed matings and those mice that did become pregnant had reduced fetal viability. The levels of antibodies reactive with SPRASA in 204 fertile and 202 infertile couples were elevated in 3 infertile but no fertile women. Together, these results indicate that SPRASA has a role in female fertility. PMID:25038051

Predicting fertility.

PubMed

Maheshwari, Abha; Bhattacharya, Siladitya; Johnson, Neil P

2008-06-01

Various predictors of fertility have been described, suggesting that none are ideal. The literature on tests of ovarian reserve is largely limited to women undergoing in vitro fertilization, and is reliant on the use of surrogate markers, such as cycle cancellation and number of oocytes retrieved, as reference standards. Currently available prediction models are far from ideal; most are applicable only to subfertile women seeking assisted reproduction, and lack external validation. Systematic reviews and meta-analyses of predictors of fertility are limited by their heterogeneity in terms of the population sampled, predictors tested and reference standards used. There is an urgent need for consensus in the design of these studies, definition of abnormal tests, and, above all, a need to use robust outcomes such as live birth as the reference standard. There are no reliable predictors of fertility that can guide women as to how long childbearing can be deferred.

Preserving Fertility while Battling Cancer

Cancer.gov

Some oncologists neglect to discuss the possibility of treatment-related infertility with patients of reproductive age. Researchers are developing decision aids to help patients make an informed, carefully considered decision about fertility.

Globalization, Foreign Investment Dependence and Agriculture Production: Pesticide and Fertilizer Use in Less-Developed Countries, 1990-2000

ERIC Educational Resources Information Center

Jorgenson, Andrew K.; Kuykendall, Kennon A.

2008-01-01

Bridging the areas of political-economic sociology, the sociology of agriculture and environmental sociology, this study tests two hypotheses derived from a refined theory of foreign investment dependence. The hypotheses state that pesticide and fertilizer use intensity in less-developed countries are both positively associated with foreign…

Obesity: modern man's fertility nemesis.

PubMed

Cabler, Stephanie; Agarwal, Ashok; Flint, Margot; du Plessis, Stefan S

2010-07-01

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.

Fertility and Childlessness in the United States.

PubMed

Baudin, Thomas; de la Croix, David

2015-06-01

We develop a theory of fertility, distinguishing its intensive margin from its extensive margin. The deep parameters are identified using facts from the 1990 US Census: (i) fertility of mothers decreases with education; (ii) childlessness exhibits a U-shaped relationship with education; (iii) the relationship between marriage rates and education is hump-shaped for women and increasing for men. We estimate that 2.5 percent of women were childless because of poverty and 8.1 percent because of high opportunity cost of childrearing. Over time, historical trends in total factor productivity and in education led to a U-shaped response in childlessness rates while fertility of mothers decreased.

Microdroplet In Vitro Fertilization Can Reduce the Number of Spermatozoa Necessary for Fertilizing Oocytes

PubMed Central

HASEGAWA, Ayumi; MOCHIDA, Keiji; TOMISHIMA, Toshiko; INOUE, Kimiko; OGURA, Atsuo

2014-01-01

Successful in vitro fertilization (IVF) in mice has been achieved using spermatozoa at concentrations specifically optimized for the experimental conditions, such as species and source of spermatozoa. Although IVF in mice is mostly performed using about 80–500 µl drops, it is expected that the number of spermatozoa used for insemination can be reduced by decreasing the size of the IVF drops. The present study was undertaken to examine the extent to which the number of spermatozoa used for IVF could be reduced by using small droplets (1 µl). We devised the experimental parameters using frozen–thawed spermatozoa from C57BL/6 mice in anticipation of broader applications to other mouse facilities. We found that as few as 5 spermatozoa per droplet could fertilize oocytes (1 or 3 oocytes per droplet), although the fertilization rates were low (13–15%). Practical fertilization rates (> 40%) could be achieved with frozen-thawed C57BL/6J spermatozoa, which are sensitive to cryopreservation, when 20 sperm per droplet were used to inseminate 3 oocytes. Even with spermatozoa from a very poor quality suspension (10% motility), about 25% of oocytes were fertilized. Our calculations indicate that the number of inseminated spermatozoa per oocyte can be reduced to 1/96–1/240 by this method. In two separate embryo transfer experiments, 60% and 47%, respectively, of embryos developed to term. Our microdroplet IVF method may be particularly advantageous when only a limited number of motile spermatozoa are available because of inadequate freezing-thawing or genetic reasons. PMID:24583808

Ammonia Emissions from agricultural fertilizer in China: From 1978 to 2008

NASA Astrophysics Data System (ADS)

Xu, P.

2015-12-01

The quantification of ammonia (NH3) emissions is essential to the more accurate quantification of atmospheric nitrogen deposition, improved air quality and the assessment of ammonia-related agricultural policy and climate mitigation strategies. Chinese agricultural fertilizer (CAF), which is widely used in China, is the nation's largest source of NH3 emissions. The quantity, geographic distribution and historical trends of these emissions remain largely uncertain. In this paper, a new CAF NH3 (CAF_NH3) emissions inventory has been compiled that exhibits the following improvements: (1) a 1 ´1 km gridded map on the county level was developed for 2008; (2) a combined bottom-up and top-down method was used for the local correction of emission factors (EFs) and parameters; (3) time trends were derived for 1978-2008 in which the spatial and temporal patterns and the uncertainties associated with the inventory were quantified; and (4) a sensitivity test was performed in which a province-level disaggregated map was compared with CAF_NH3 emissions for 2008. The total CAF_NH3 emissions for 2008 were 8.4 TgNH3·yr-1 (a 6.6-9.8 Tg interquartile range). From 1978 to 2008, annual NH3 emissions fluctuated with three peaks (1987, 1996 and 2005), and total emissions increased from 3.2 to 8.4 Tg at an annual rate of 3.0%. During the study period, the contribution of livestock manure spreading increased from 37.0% to 45.5% because of changing fertilization practices and the rapid increase in egg, milk and meat consumption. The average contribution of synthetic fertilizer, which has a positive effect on crop yields, was approximately 38.3% (minimum: 33.4%; maximum: 42.7%). With rapid urbanization causing a decline in the rural population, the contribution of the rural excrement sector varied widely between 20.3% and 8.5%. The average contributions of cake fertilizer and straw returning were approximately 3.8% and 4.5%, respectively, thus small and stable. Collectively, the CAF NH3

Nanotechnology - A path forward for developing nations

NASA Astrophysics Data System (ADS)

Shah, S. Ismat; Powers, Thomas M.

2015-10-01

One of the major issues with technology in general, and nanotechnology in particular, is that it could exacerbate the divide between developed and developing nations. If the benefits of the research do not flow beyond the national and geographical borders of the traditional major bastions of R&D, these benefits will not be equally and globally available. The consequence is that the technological divide becomes wider at the expense of mutual reliance. As much as developed nations need to rethink the strategy and the policy to bring nanotechnology products to market with the goal of global prosperity, developing nations cannot afford to simply wait for the lead from the developed nations. In the spirit of collaboration and collegiality, we describe issues with the current practices in nanotechnology R&D in the developing world and suggest a path for nanotechnology research in energy, water and the environment that developing nations could follow in order to become contributors rather than simply consumers.

Knowledge about factors that influence fertility among Australians of reproductive age: a population-based survey.

PubMed

Hammarberg, Karin; Setter, Tracey; Norman, Robert J; Holden, Carol A; Michelmore, Janet; Johnson, Louise

2013-02-01

To explore knowledge about the effects on fertility of age, obesity, smoking, and timing of intercourse among Australians of reproductive age. Telephone survey of a representative sample of Australians. Not applicable. Australians aged 18 to 45 years who wish to have a child or another child now or in the future. None. Knowledge about the effect on fertility of age, obesity, smoking, and timing of intercourse. A total of 462 interviews were conducted. The majority of respondents underestimated, by about 10 years, the age at which male and female fertility starts to decline. Only one in four correctly identified that female fertility starts to decline before age 35, and one in three identified that male fertility starts to decline before age 45. Most (59%) were aware that female obesity and smoking affect fertility, but fewer recognized that male obesity (30%) and smoking (36%) also influence fertility. Almost 40% of respondents had inadequate knowledge of when in the menstrual cycle a woman is most likely to conceive. Considerable knowledge gaps about modifiable factors that affect fertility were identified. These are targeted in a national education campaign to promote awareness of factors that influence fertility. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Fertility preservation and cancer: How many persons are concerned?

PubMed

Le Bihan-Benjamin, Christine; Hoog-Labouret, Natalie; Lefeuvre, Delphine; Carré-Pigeon, Frédérique; Bousquet, Philippe Jean

2018-06-01

A significant proportion of cancer survivors experience chronic health sequelae, one of them being fertility impairment. However, even if many reports, guidelines and positions papers focus on fertility preservation and its needs, access to fertility preservation is not currently offered to all the patients concerned, and the targeted population is not well counted. A cross sectional study was conducted using the French cancer cohort, a cohort covering the whole French population and including around 7 million of cancer patients. Women under the age of 40 and men under the age of 60 included in the cancer cohort in 2013 who had, in the first year, cancer surgery, chemotherapy or radiotherapy were considered. Patients treated by surgery alone for cancers in locations distant from the reproductive organs, or being treated for a cancer the past 3 years were excluded. The number of patients concerned by fertility preservation was estimated at a national and regional level, and by cancer types. 40,000 patients - 30,000 men under the age of 60 years and 10,000 women under the age of 40 years - were identified. A second estimation concerning women under the age of 35 and men under 50 reduced the number of patients to 17,200-10,400 men and 6800 women. The most frequent locations were malignant neoplasm of lymphoid and hematopoietic tissue, lung cancer, cervix uteri, prostate and colorectal cancer. In 2014, around 5 400 persons had a preservation. Around 17,200 cancer patients of reproductive age should be informed about the fertility preservation options available. Medical professionals have to better integrate in their daily practice fertility preservation. Copyright © 2018 Elsevier B.V. All rights reserved.

Does fertility treatment increase the risk of uterine cancer? A meta-analysis.

PubMed

Saso, Srdjan; Louis, Louay S; Doctor, Farah; Hamed, Ali Hassan; Chatterjee, Jayanta; Yazbek, Joseph; Bora, Shabana; Abdalla, Hossam; Ghaem-Maghami, Sadaf; Thum, Meen-Yau

2015-12-01

An ongoing debate over the last two decades has focused on whether fertility treatment in women may lead to an increased risk of developing uterine cancer over a period of time. Uterine cancer (including mainly endometrial carcinoma and the less common uterine sarcoma) is the commonest reproductive tract cancer and the fourth commonest cancer in women in the UK. Our objective was to assess the association between fertility drugs used in the treatment of female infertility (both as an independent therapy and during in vitro fertilization cycles) and the development of uterine cancer. A literature search was performed using Medline, Embase, Cochrane Library and Google Scholar databases for comparative studies until December 2014 to investigate a clinical significance of fertility treatment on the incidence of developing uterine cancer. General and MESH search headings, as well as the 'related articles' function were applied. All comparative studies of 'fertility treatment' versus 'non-fertility treatment' reporting the incidence of uterine cancer as an outcome were included. Uterine cancer incorporated the following terms: uterine cancer, uterine body tumours, uterine sarcomas and endometrial cancers. The primary outcome of interest was the uterine cancer incidence in all 'fertility treatment' versus 'non-fertility treatment' patient groups. Secondary outcomes of interest were: (a) uterine cancer incidence in 'IVF' versus 'non-IVF' patient groups; and (b) uterine cancer incidence according to type of fertility drug used. Odds ratio was the summary statistic. Random-effects modelling, graphical exploration and sensitivity analysis were used to evaluate the consistency of the calculated treatment effect. We included six studies in our final analysis, which comprised 776,224 patients in total. Of these, 103,758 had undergone fertility treatment and 672,466 had not. There was 100% agreement between the two reviewers regarding the data extraction. All the studies

Law No. 711 on fertilization outside the human body, 14 June 1988.

PubMed

1988-01-01

This Swedish Law reads as follows: "Section 1: this Law shall apply to the fertilization of a woman's egg outside her body, for the purpose of producing a child. Section 2: an egg which has been fertilized outside the body of a woman may not be introduced into her body unless: 1) the woman is married or living in a state of cohabitation; 2) the husband or cohabitant gives his written consent; and 3) the egg is the woman's own and has been fertilized with the sperm of her husband or cohabitant. Section 3: unless the authorization of the National Board of Health and Welfare is obtained, fertilization outside the human body may only be carried out in a general hospital. Section 4: persons committing a breach of Section 2 or 3 habitually or for gain shall be liable to a fine or to a prison sentence not exceeding six months." full text

Effects of 17beta-estradiol, and its metabolite, 4-hydroxyestradiol on fertilization, embryo development and oxidative DNA damage in sand dollar (Dendraster excentricus) sperm.

PubMed

Rempel, Mary Ann; Hester, Brian; Deharo, Hector; Hong, Haizheng; Wang, Yinsheng; Schlenk, Daniel

2009-03-15

Oxidative compounds have been demonstrated to decrease the fertilization capability and viability of offspring of treated spermatozoa. As estrogen and its hydroxylated metabolites readily undergo redox cycling, this study was undertaken to determine if estrogens and other oxidants could damage DNA and impair sperm function. Sperm was preexposed to either 17beta-estradiol (E2), 4-hydroxyestradiol (4OHE2) or the oxidant t-butyl hydroperoxide (t-BOOH), and allowed to fertilize untreated eggs. The fertilization rates and development of the larvae were assessed, as well as the amount of 8-oxodeoxyguanosine (8-oxodG) as an indication of oxidative DNA damage. All compounds caused significant decreases in fertilization and increases in pathological abnormalities in offspring, with 4OHE2 being the most toxic. Treatment with 4OHE2 caused a significant increase of 8-oxodG, but E2 failed to show any effect. Pathological abnormalities were significantly correlated (r(2)=0.44, p< or =0.05) with 8-oxodG levels in sperm treated with t-BOOH and 4OHE2, but not E2. 8-OxodG levels also were somewhat weakly correlated with impaired fertilization in 4OHE2-treated sperm (r(2)=0.33, p< or =0.05). The results indicate that biotransformation of E2 to 4OHE2 enhances oxidative damage of DNA in sperm, which can reduce fertilization and impair embryonic development, but other mechanisms of action may also contribute to these effects.

Effects of 17β-estradiol, and its metabolite, 4-hydroxyestradiol on fertilization, embryo development and oxidative DNA damage in sand dollar (Dendraster excentricus) sperm

PubMed Central

Rempel, Mary Ann; Hester, Brian; DeHaro, Hector; Hong, Haizheng; Wang, Yinsheng; Schlenk, Daniel

2011-01-01

Oxidative compounds have been demonstrated to decrease the fertilization capability and viability of offspring of treated spermatozoa. As estrogen and its hydroxylated metabolites readily undergo redox cycling, this study was undertaken to determine if estrogens and other oxidants could damage DNA and impair sperm function. Sperm was preexposed to either 17β-estradiol (E2), 4-hydroxyestradiol (4OHE2) or the oxidant t-butyl hydroperoxide (t-BOOH), and allowed to fertilize untreated eggs. The fertilization rates and development of the larvae were assessed, as well as the amount of 8-oxodeoxyguanosine (8-oxodG) as an indication of oxidative DNA damage. All compounds caused significant decreases in fertilization and increases in pathological abnormalities in offspring, with 4OHE2 being the most toxic. Treatment with 4OHE2 caused a significant increase of 8-oxodG, but E2 failed to show any effect. Pathological abnormalities were significantly correlated (r2 = 0.44, p ≤ 0.05) with 8-oxodG levels in sperm treated with t-BOOH and 4OHE2, but not E2. 8-OxodG levels also were somewhat weakly correlated with impaired fertilization in 4OHE2-treated sperm (r2 = 0.33, p ≤ 0.05). The results indicate that biotransformation of E2 to 4OHE2 enhances oxidative damage of DNA in sperm, which can reduce fertilization and impair embryonic development, but other mechanisms of action may also contribute to these effects. PMID:19171371

DNA damage in bovine sperm does not block fertilization and early embryonic development but induces apoptosis after the first cleavages.

PubMed

Fatehi, A N; Bevers, M M; Schoevers, E; Roelen, B A J; Colenbrander, B; Gadella, B M

2006-01-01

The main goal of this study was to investigate whether and at what level damage of paternal DNA influences fertilization of oocytes and early embryonic development. We hypothesized that posttesticular sperm DNA damage will only marginally affect sperm physiology due to the lack of gene expression, but that it will affect embryo development at the stage that embryo genome (including the paternal damaged DNA) expression is initiated. To test this, we artificially induced sperm DNA damage by irradiation with x- or gamma rays (doses of 0-300 Gy). Remarkably, sperm cells survived the irradiation quite well and, when compared with nonirradiated cells, sperm motility and integrity of plasma membrane, acrosome, and mitochondria were not altered by this irradiation treatment. In contrast, a highly significant logarithmic relation between irradiation dose and induced DNA damage to sperm cells was found by both terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) and the acridin orange assay. Despite the DNA damage, irradiated sperm cells did not show any sign of apoptosis (nuclear fragmentation, depolarization of inner mitochondrial membranes, or phospholipid scrambling) and were normally capable of fertilizing oocytes, as there was no reduction in cleavage rates when compared with nonirradiated sperm samples up to irradiation doses of less than 10 Gy. Further embryonic development was completely blocked as the blastocyst rates at days 7 and 9 dropped from 28% (nonirradiated sperm) to less than 3% by greater than 2.5-Gy-irradiated sperm. This block in embryonic development was accompanied with the initiation of apoptosis after the second or third cleavage. Specific signs of apoptosis, such as nuclear fragmentation and aberrations in spindle formation, were observed in all embryos resulting from in vitro fertilization with irradiated sperm (irradiation doses >1.25 Gy). The results show that sperm DNA damage does not impair fertilization of the

What is new in 2017? Update on fertility preservation in cancer patients.

PubMed

Winkler-Crepaz, Katharina; Böttcher, Bettina; Toth, Bettina; Wildt, Ludwig; Hofer-Tollinger, Susanne

2017-12-01

The prevention of fertility loss due to cancer treatment as well as non-malignant causes has been gaining importance over the last few decades. Clinically applied modalities for fertility preservation in cancer patients include cryopreservation of oocytes and embryos, the application of GnRH agonists, ovarian tissue banking, and cryopreservation of ejaculated or surgically extracted sperm. In addition, several new possibilities to restore fertility are currently being investigated, such as the establishment of in-vitro culture systems for gonadal tissue, the development of artificial gonads, and the application of germline stem cells. This review aims to provide an update on the methods currently applied in clinical practice for fertility preservation, as well as to summarize the progress made in the development of novel strategies for fertility preservation.

Educational Goals and National Development

ERIC Educational Resources Information Center

Umapathy, K. Setty

1974-01-01

Discusses educational goals in ancient India, western education in India, educational goals in free India, goals and national development, and the problem of poverty and equal distribution of national gains. (Author/PG)

Fertility transition: forecast for demography.

PubMed

Caputo, M; Nicotra, M; Gloria-Bottini, E

2008-08-01

By the end of the 20th century most industrialized nations had undergone the so-called fertility transition, characterized by a reduction in fertility to below replacement level and a delay in age at initiation of child-bearing. An emerging concern is the severe economic and social consequences of this demographic decline. We present an overview of fertility changes in Italy in the second half of the 20th century and a mathematical model that may provide projections for the future of the demographic situation. Starting in 1950 the increment of the number of children born in Italy is initially positive; however, beginning in 1965 the trend suddenly becomes negative, and this negative trend further increased in 1975. A slight improvement is observed in 1980, followed by a stable situation beginning in 1987. Relevant socioeconomic and cultural events in Italy coincide with these variations in the fertility trend. Malnutrition, which had been endemic for centuries in some areas of central and southern Italy, disappeared rather abruptly in early 1960. The improvement in the economic situation was also associated with a decrease in illiteracy and with many sociocultural changes, with the emergence of new demands that decreased propensity for childbearing. The additional deceleration observed in 1975 corresponds to the diffusion of contraceptive procedures. The progression of sociocultural changes has led to a progressive liberation of women from the biological burden of childbearing. Two phenomena seem relevant in this context: women's emerging interest in entering the workforce and the possibility to disconnect sex from childbearing. The social function of feminism has overwhelmed the primary function of survival and diffusion of the species, giving rise to relevant and worrying demographic effects. However, the modern woman has an unconscious memory of her primary biological role, depending on both her genetic structure and cultural heritage, that should bring about a

[Variations of soil fertility level in red soil region under long-term fertilization].

PubMed

Yu, Han-qing; Xu, Ming-gang; Lü, Jia-long; Bao, Yao-xian; Sun, Nan; Gao, Ju-sheng

2010-07-01

Based on the long-term (1982-2007) field experiment of "anthropogenic mellowing of raw soil" at the Qiyang red soil experimental station under Chinese Academy of Agricultural Sciences, and by using numerical theory, this paper studied the variations of the fertility level of granite red soil, quaternary red soil, and purple sandy shale soil under six fertilization patterns. The fertilization patterns included non-fertilization (CK), straw-returning without fertilizers (CKR), chemical fertilization (NPK), NPK plus straw-return (NPKR), rice straw application (M), and M plus straw-return (MR). The soil integrated fertility index (IFI) was significantly positively correlated with relative crop yield, and could better indicate soil fertility level. The IFI values of the three soils all were in the order of NPK, NPKR > M, MR > CK, CKR, with the highest value in treatment NPKR (0.77, 0.71, and 0.71 for granite red soil, quaternary red soil, and purple sandy shale soil, respectively). Comparing with that in the treatments of no straw-return, the IFI value in the treatments of straw return was increased by 6.72%-18.83%. A turning point of the IFI for all the three soils was observed at about 7 years of anthropogenic mellowing, and the annual increasing rate of the IFI was in the sequence of purple sandy shale soil (0.016 a(-1)) > quaternary red clay soil (0.011 a(-1)) > granite red soil (0.006 a(-1)). It was suggested that a combined application of organic and chemical fertilizers and/or straw return could be an effective and fast measure to enhance the soil fertility level in red soil region.

Fertility and Life Satisfaction in Rural Ethiopia.

PubMed

Conzo, Pierluigi; Fuochi, Giulia; Mencarini, Letizia

2017-08-01

Despite recent strong interest in the link between fertility and subjective well-being, the focus has centered on developed countries. For poorer countries, in contrast, the relationship remains rather elusive. Using a well-established panel survey-the Ethiopian Rural Household Survey (ERHS)-we investigate the empirical relationship between fertility and life satisfaction in rural Ethiopia, the largest landlocked country in Africa. Consistent with the fertility theories for developing countries and with the sociodemographic characteristics of rural Ethiopia, we hypothesize that this relationship varies by gender and across life stages, being more positive for men and for parents in old age. Indeed, our results suggest that older men benefit the most in terms of life satisfaction from having a large number of children, while the recent birth of a child is detrimental for the subjective well-being of women at reproductive ages. We address endogeneity issues by using lagged life satisfaction in ordinary least squares regressions, through fixed-effects estimation and the use of instrumental variables.

Endogenous fertility, Ricardian equivalence, and debt management policy.

PubMed

Lapan, H E; Enders, W

1990-03-01

This paper develops a model in which dynastic families optimally determine fertility. Government debt represents a tax on future generations and on childbearing; the Ricardian Equivalence Hypothesis does not hold. Debt is welfare reducing in that it distorts the fertility decision. An increase in government debt induces a decline in fertility and an increase in the steady state capital/labor ratio. If a government inherits an existing stock of debt, the 1st-best policy is to eliminate the debt immediately. In other situations the optimal debt management policy will not, in general, entail a total elimination of the debt.

Historical nitrogen fertilizer use in agricultural ecosystems of the contiguous United States during 1850-2015: application rate, timing, and fertilizer types

NASA Astrophysics Data System (ADS)

Cao, Peiyu; Lu, Chaoqun; Yu, Zhen

2018-06-01

A tremendous amount of anthropogenic nitrogen (N) fertilizer has been applied to agricultural lands to promote crop production in the US since the 1850s. However, inappropriate N management practices have caused numerous ecological and environmental problems which are difficult to quantify due to the paucity of spatially explicit time-series fertilizer use maps. Understanding and assessing N fertilizer management history could provide important implications for enhancing N use efficiency and reducing N loss. In this study, we therefore developed long-term gridded maps to depict crop-specific N fertilizer use rates, application timing, and the fractions of ammonium N (NH4+-N) and nitrate N (NO3--N) used across the contiguous US at a resolution of 5 km × 5 km during the period from 1850 to 2015. We found that N use rates in the US increased from 0.22 g N m-2 yr-1 in 1940 to 9.04 g N m-2 yr-1 in 2015. Geospatial analysis revealed that hotspots for N fertilizer use have shifted from the southeastern and eastern US to the Midwest, the Great Plains, and the Northwest over the past century. Specifically, corn in the Corn Belt region received the most intensive N input in spring, followed by the application of a large amount of N in fall, implying a high N loss risk in this region. Moreover, spatial-temporal fraction of NH4+-N and NO3--N varied largely among regions. Generally, farmers have increasingly favored ammonia N fertilizers over nitrate N fertilizers since the 1940s. The N fertilizer use data developed in this study could serve as an essential input for modeling communities to fully assess N addition impacts, and improve N management to alleviate environmental problems. Datasets used in this study are available at https://doi.org/10.1594/PANGAEA.883585.

Knowledge and Use of Contraception in Twenty Developing Countries. Reports on the World Fertility Survey 3.

ERIC Educational Resources Information Center

Mamlouk, Maria

This report, third in a series based on data resulting from the World Fertility Survey (WFS), examines the extent of knowledge and use of contraception in 20 developing countries. The data analyzed in this report indicate that in 19 of the 20 countries (the exception being Nepal), three-quarters or more of the women who are or have been married…

Effects of fertilization on the growth and development of a Japanese larch plantation in West Virginia

Treesearch

James N. Kochenderfer; H. Clay Smith; Jerry T. Crews

1995-01-01

The effects of fertilization on the growth and development of a Japanese larch plantation in central West Virginia were evaluated after 9 years. Mean height and diameter growth of the larch trees were greater on the unfertilized plots. Foliar and soil chemical analyses were used to examine this apparent anomaly. Japanese larch demonstrated an ability to grow well on a...

Development of organic fertilizers from food market waste and urban gardening by composting in Ecuador

PubMed Central

Jara-Samaniego, J.; Pérez-Murcia, M. D.; Bustamante, M. A.; Paredes, C.; Pérez-Espinosa, A.; Gavilanes-Terán, I.; López, M.; Marhuenda-Egea, F. C.; Brito, H.; Moral, R.

2017-01-01

Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition

Development of organic fertilizers from food market waste and urban gardening by composting in Ecuador.

PubMed

Jara-Samaniego, J; Pérez-Murcia, M D; Bustamante, M A; Paredes, C; Pérez-Espinosa, A; Gavilanes-Terán, I; López, M; Marhuenda-Egea, F C; Brito, H; Moral, R

2017-01-01

Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition

[Mechanisms for the increased fertilizer nitrogen use efficiency of rice in wheat-rice rotation system under combined application of inorganic and organic fertilizers].

PubMed

Liu, Yi-Ren; Li, Xiang; Yu, Jie; Shen, Qi-Rong; Xu, Yang-Chun

2012-01-01

A pot experiment was conducted to study the effects of combined application of organic and inorganic fertilizers on the nitrogen uptake by rice and the nitrogen supply by soil in a wheat-rice rotation system, and approach the mechanisms for the increased fertilizer nitrogen use efficiency of rice under the combined fertilization from the viewpoint of microbiology. Comparing with applying inorganic fertilizers, combined application of organic and inorganic fertilizers decreased the soil microbial biomass carbon and nitrogen and soil mineral nitrogen contents before tillering stage, but increased them significantly from heading to filling stage. Under the combined fertilization, the dynamics of soil nitrogen supply matched best the dynamics of rice nitrogen uptake and utilization, which promoted the nitrogen accumulation in rice plant and the increase of rice yield and biomass, and increased the fertilizer nitrogen use efficiency of rice significantly. Combined application of inorganic and organic fertilizers also promoted the propagation of soil microbes, and consequently, more mineral nitrogen in soil was immobilized by the microbes at rice early growth stage, and the immobilized nitrogen was gradually released at the mid and late growth stages of rice, being able to better satisfy the nitrogen demand of rice in its various growth and development stages.

The effect of cigarette smoke on fertilization and pre-implantation development: assessment using animal models, clinical data, and stem cells.

PubMed

Talbot, Prue; Lin, Sabrina

2011-01-01

Numerous studies have repeatedly shown that women who smoke experience problems establishing and maintaining pregnancies, and recent work has further demonstrated that the in utero effects of smoke may not be manifested until months or even years after birth. The purpose of this review is to examine the recent literature dealing with the effects of cigarette smoke on the earliest stages of human prenatal development. Studies in this area have included the use of animal models, patients undergoing in vitro fertilization, and embryonic stem cell models. Events leading to fertilization, such as cumulus expansion, hyperactivation of sperm motility, and oocyte pick-up by the oviduct are all impaired by smoke exposure in animal models. Steps crucial to fertilization such as the acrosome reaction and sperm binding to the zona pellucida are likewise inhibited by cigarette smoke. Preimplantation embryos and stem cells that model embryos show a number of adverse responses to smoke exposure, including poor adhesion to extracellular matrices, diminished survival and proliferation, and increased apoptosis. The current literature demonstrates that the earliest stages of prenatal development are sensitive to smoke exposure and indicates that pregnant women should be advised not to smoke during this time.

Female employment reduces fertility in rural Senegal.

PubMed

Van den Broeck, Goedele; Maertens, Miet

2015-01-01

Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

Plant fertilizer poisoning

MedlinePlus

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. ...

Those ubiquitous fertility trends: United States, 1945-1979.

PubMed

Sweet, J A; Rindfuss, R R

1983-01-01

all the black subgroups was markedly less than in the 1970-76 periold, and for many of the subgroups the trend was reversed and fertility increased. In summary, the fertility trends noted for 1970-79 were pervasive for almost all the subgroups for both blacks and whites; i.e., there was a marked decline in fertility between 1970-76 and than a reversal or slowing down of the decline during the 1976-79 for all black and white subgroups. Cross-sectional fertility differences in the subgroups in 1970 and in 1979 were quite similar, and fertility rates differed markedly for the separate subgroups. These differences do not, of course, explain the pervasive trends observed in the analysis of the fertility rates over time. A similar study assessing fertility trends among subgroups for the early 1940's through the late 1960s also revealed the pervasive nature of period fertility trends. Demographers have not as yet been able to explain these shifts in fertility that cut across all subgroups in the US and which also characterize the period fertility rates in other developed countries. Tables provided information on 1) total fertility rates by educational level and by geographical region for 1945-1975; 2) % change in number of own children less than 3 years of age among women under age 40 by maternal age, maternal education, initial parity, geographical region, and husband's income; and 3) mean number of own children less than 3 years of age among women under age 40 by maternal age, education, parity, region, and husband's income.

A Multimonial Logit Analysis of Teenage Fertility and High School Completion.

ERIC Educational Resources Information Center

Ribar, David C.

1993-01-01

Uses data from the 1979 National Longitudinal Survey of Youth to examine economic, institutional, and sociological antecedents of high school completion and adolescent fertility. Welfare generosity appears to have a significant positive effect on adolescent childbearing. Other important determinants of teenage parenthood and educational attainment…

Conceptual Design of Fertilizer Applicator for Oil Palm on Terrace Cultivation

NASA Astrophysics Data System (ADS)

Hermawan, W.

2018-05-01

The mechanical application of fertilizer for oil palm planted on terraces is still constrained by the narrow path which is difficult to pass by a power spreader. The objective of this research was to develop a conceptual design of fertilizer applicator for oil palm planted on terraces. The design requirements were developed based on a) terrace and track conditions, b) fertilizers and fertilization conditions, c) available prime movers, and d) user needs. Five design concepts were obtained: 1) an applicator with left and right arms to distribute the fertilizer, 2) an all-terrain vehicle equipped with a manually operated fertilizer injector, 3) an applicator equipped with a hole digger, 4) an applicator equipped with a shovel, and 5) an applicator equipped with a rotary tiller. The concepts were evaluated and compared with the current power spreader. The evaluation results showed that the applicator equipped with a rotary tiller had the most advantages on the expected criteria. The final design concept uses a 110 cm wide mini crawler tractor as the prime mover and is equipped with a hopper and a spinner disk for metering and conveying the fertilizer, and a 20 cm wide rotary tiller in the front of the machine.

The fertility decline in Kenya.

PubMed

Robinson, W C; Harbison, S F

1995-01-01

In Sub-Saharan Africa Kenya is a prime example of a country experiencing a rapid decline in fertility and greater contraceptive prevalence. These changes have occurred since 1980 when fertility was high at 8.0 children per woman. In 1993 the total fertility rate (TFR) was 5.4, and the growth rate declined to about 2.0%. This transition is swifter than any country in contemporary Asia or historical Europe. The likely projection for Kenya is attainment of replacement level fertility during the 2020s and a leveling of population at about 100 million persons. Fertility has declined the most in urban areas and central and eastern regions. Bongaarts' proximate determinants (TFR, total marital fertility rate, total natural marital fertility rate, and total fecundity) are reduced to the proportion of currently married women using contraception, the proportion in lactational nonfecund status, and the proportion currently married. Actual fertility change is accounted for by total fertility change of 3.0 children. Lactational infecundability accounts for 0.5 potential births, and changes in marital fertility account for 1.0 reduced births per woman. About 70% of fertility reduction is accounted for by contraception and abortion. During 1977-78 80% of fertility control was due to lactational nonfecundity, 10% to nonmarriage, and 10% to contraception. In 1993 lactational nonfecundity accounted for 50% of the reduction, nonmarriage for 20%, and abortion about 30%. Future fertility is expected to be dependent on contraceptive prevalence. Kenya has experienced the Coale paradigm of preconditions necessary for demographic transition (willing, ready, and able). High fertility in Africa is not intractable. Creating the change in attitudes that leads to readiness is linked to education, health, and exposure to modernizing media and urban lifestyles. The public sector family planning program in Kenya has created the opportunity for access and availability of contraception. The key

Development and validation of the FertiMed questionnaire assessing patients' experiences with hormonal fertility medication.

PubMed

Lankreijer, K; D'Hooghe, T; Sermeus, W; van Asseldonk, F P M; Repping, S; Dancet, E A F

2016-08-01

Can a valid and reliable questionnaire be developed to assess patients' experiences with all of the characteristics of hormonal fertility medication valued by them? The FertiMed questionnaire is a valid and reliable tool that assesses patients' experiences with all medication characteristics valued by them and that can be used for all hormonal fertility medications, irrespective of their route of administration. Hormonal fertility medications cause emotional strain and differ in their dosage regime and route of administration, although they often have comparable effectiveness. Medication experiences of former patients would be informative for medication choices. A recent literature review showed that there is no trustworthy tool to compare patients' experiences of medications with differing routes of administration, regarding all medication characteristics which patients value. The items of the new FertiMed questionnaire were generated by literature review and 23 patient interviews. In 2013, 411 IVF-patients were asked to retrospectively complete the FertiMed questionnaire to assess 1 out of the 8 different medications used for ovarian stimulation, induction of pituitary quiescence, ovulation triggering or luteal support. In total, 276 patients (on average 35 per medication) from 2 university fertility clinics (Belgium, the Netherlands) completed the FertiMed questionnaire (67% response rate). The FertiMed questionnaire questioned whether items were valued by patients and whether these items were experienced while using the assessed medication. Hence, the final outcome 'Experiences with Valued Aspects Scores' (EVAS) combined importance and experience ratings. The content and face validity, reliability, feasibility and discriminative potential of the FertiMed questionnaire were tested and changes were made accordingly. Patient interviews defined 51 items relevant to seven medication characteristics previously proved to be important to patients. Item analysis deleted

Malaria ecology, child mortality & fertility.

PubMed

McCord, Gordon C; Conley, Dalton; Sachs, Jeffrey D

2017-02-01

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 © 2016 Elsevier B.V. All rights reserved.

Female Fertility Issues

Cancer.gov

Fertility issues are common in women getting cancer treatment. Fertility preservation options include egg freezing, embryo freezing, ovarian tissue freezing, ovarian shielding and ovarian transposition. Resources, support, and clinical trials are listed.

The Relationship of Economic Variations to Mortality and Fertility Patterns on the Navajo Reservation. Lake Powell Research Project Bulletin Number 20, April 1976.

ERIC Educational Resources Information Center

Kunitz, Stephen J.

Divided into three sections, this research bulletin presents: (1) a brief review of changes in the American Indian mortality and fertility rates, illustrating a transition process much like that experienced by developing nations; (2) an analysis of variations in the social and economic organization of different parts of the Navajo Reservation; (3)…

A national study of the provision of oncology sperm banking services among Canadian fertility clinics.

PubMed

Yee, S; Buckett, W; Campbell, S; Yanofsky, R A; Barr, R D

2013-07-01

The purpose of this study was to survey the current state of oncology sperm banking services provided by fertility clinics across Canada. A total of 78 Canadian fertility facilities were invited to complete a questionnaire related to the availability, accessibility, affordability and utilisation of sperm banking services for cancer patients. The total response rate was 59%, with 20 (69%) in vitro fertilisation clinics and 26 (53%) other fertility centres returning the survey. A total of 24 responding facilities accepted oncology sperm banking referrals. The time frame to book the first banking appointment for 19 (79%) facilities was within 2 days. Inconsistent practice was found regarding the consent process for cancer patients who are of minority age. Eight (33%) facilities did not provide any subsidy and charged a standard banking fee regardless of patients' financial situations. Overall, the utilisation of oncology sperm banking services was low despite its availability and established efficacy, suggesting that Canadian cancer patients are notably underserved. The study has highlighted some important issues for further consideration in improving access to sperm banking services for cancer patients, especially for adolescents. Better collaboration between oncology and reproductive medicine to target healthcare providers would help to improve sperm banking rates. © 2013 John Wiley & Sons Ltd.

Safety and efficacy of fertility-regulating methods: a decade of research.

PubMed Central

Skegg, D. C.

1999-01-01

An international venture was launched in 1985 to fill a recognized gap in post-marketing surveillance of fertility-regulating methods. For this purpose a new task force was set up by the Special Programme of Research, Development, and Research Training in Human Reproduction, which is cosponsored by the United Nations Development Programme, the United Nations Population Fund, the World Bank, and WHO. Research priorities were chosen and epidemiological studies inaugurated, involving a total of 47 countries--mostly from the developing world. Important progress has been made, especially in helping to define the beneficial and possible adverse effects of oral contraceptives on the risk of neoplasia; in showing that the injectable contraceptive depot-medroxyprogesterone acetate protects against endometrial cancer and does not increase the overall risk of breast cancer, in clarifying which groups of women are susceptible to the rare cardiovascular complications of oral contraceptives (myocardial infarction, stroke, and venous thromboembolism); and in establishing the long-term effectiveness and safety of intrauterine devices. The research has already made a significant impact on family planning policies and practice. Critical appraisal of this venture, which has been modestly funded, confirms the value of mission-oriented research. It also illustrates the potential of collaboration that bridges the global divide between developing and developed countries. PMID:10534894

Safety and efficacy of fertility-regulating methods: a decade of research.

PubMed

Skegg, D C

1999-01-01

An international venture was launched in 1985 to fill a recognized gap in post-marketing surveillance of fertility-regulating methods. For this purpose a new task force was set up by the Special Programme of Research, Development, and Research Training in Human Reproduction, which is cosponsored by the United Nations Development Programme, the United Nations Population Fund, the World Bank, and WHO. Research priorities were chosen and epidemiological studies inaugurated, involving a total of 47 countries--mostly from the developing world. Important progress has been made, especially in helping to define the beneficial and possible adverse effects of oral contraceptives on the risk of neoplasia; in showing that the injectable contraceptive depot-medroxyprogesterone acetate protects against endometrial cancer and does not increase the overall risk of breast cancer, in clarifying which groups of women are susceptible to the rare cardiovascular complications of oral contraceptives (myocardial infarction, stroke, and venous thromboembolism); and in establishing the long-term effectiveness and safety of intrauterine devices. The research has already made a significant impact on family planning policies and practice. Critical appraisal of this venture, which has been modestly funded, confirms the value of mission-oriented research. It also illustrates the potential of collaboration that bridges the global divide between developing and developed countries.

Attitudes towards fertility control.

PubMed

Muthal, S

1992-03-01

"The present work aims to determine...the effectiveness of traditional mixed and modern attitudes towards fertility. Here fertility refers to the number of children actually born to a woman. Randomly chosen 400 women belonging to different ethnic strains from Sagar town [India] constitute the data for the present study. The scaling technique is devised to obtain accurate values for fertility noticed among different populations. Thus an attempt has been made to study whether education, income, caste, age and age at marriage have direct association with fertility." excerpt

Abiotic processes are insufficient for fertile island development: A 10-year artificial shrub experiment in a desert grassland

USDA-ARS?s Scientific Manuscript database

The relative importance of biotic and abiotic processes in the development of “fertile islands” in dryland systems has rarely been investigated. Here we approached this question by using artificial shrubs, which exclude plant litter production and soil nutrient uptake, but retain the functions of tr...

Male Fertility Issues

Cancer.gov

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.

Genetically-induced Estrogen Receptor Alpha mRNA (Esr1) Overexpression Does Not Adversely Affect Fertility or Penile Development in Male Mice

PubMed Central

Heath, John; Abdelmageed, Yazeed; Braden, Tim D.; Williams, Carol S.; Williams, John W.; Paulose, Tessie; Hernandez-Ochoa, Isabel; Gupta, Rupesh; Flaws, Jodi A.; Goyal, Hari O.

2011-01-01

Previously, we reported that estrogen receptor alpha mRNA (Esr1) or protein (ESR1) overexpression resulting from neonatal exposure to estrogens in rats was associated with infertility and mal-developed penis characterized by reduced length and weight and abnormal accumulation of fat cells. The objective of this study was to determine if mutant male mice overexpressing Esr1 are naturally infertile or have reduced fertility and/or develop abnormal penis. The fertility parameters, including fertility and fecundity indices, numbers of days from the day of cohabitation to the day of delivery, and numbers of pups per female, were not altered from controls, as a result of Esr1 overexpression. Likewise, penile morphology, including the length, weight, and diameter and os penis development, was not altered from controls. Conversely, weights of the seminal vesicles and bulbospongiosus and levator ani (BS/LA) muscles were significantly (P < 0.05) lower as compared to controls; however, the weight of the testis, the morphology of the testis and epididymis, and the plasma and testicular testosterone concentration were not different from controls. Hence, the genetically-induced Esr1 overexpression alone, without an exogenous estrogen exposure during the neonatal period, is unable to adversely affect the development of the penis as well as other male reproductive organs, except limited, but significant, reductions in weights of the seminal vesicles and BS/LA muscles. PMID:20930192

The relationship of bull fertility to sperm nuclear shape

USGS Publications Warehouse

Ostermeier, G.C.; Sargeant, G.A.; Yandell, B.S.; Parrish, J.J.

2001-01-01

group had a linear relationship (r .89, P .05) with fertility. To construct a plot of mean sperm shapes, a novel technique to automatically orient and identify the anterior tip of the sperm head was developed. The mean nuclear shape of high-fertility sperm was more elongated and tapered than those of lower fertility. A discriminant function (P .05) was also constructed that separated the 6 bulls into 2 groups based only on the harmonic amplitudes or sperm nuclear shape. The bulls were correctly classified into the 2 fertility groups. A comparison of sperm chromatin structure analysis (SCSA) and harmonic amplitudes found that overall size variance, anterior roundness, and posterior taperedness of sperm nuclei were related to chromatin stability (P .05). Some of the differences observed in sperm nuclear shape between the high- and lower-fertility bulls may be explained by varying levels of chromatin stability. However, sperm nuclear shape appears to contain additional information from chromatin stability alone. In this particular study, with 6 bulls, all with good chromatin quality, sperm nuclear shape was a better predictor of bull fertility.

The cultural evolution of fertility decline

PubMed Central

Colleran, Heidi

2016-01-01

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

Fertility Decline in Rural China: A Comparative Analysis

PubMed Central

Harrell, Stevan; Yuesheng, Wang; Hua, Han; Santos, Gonçalo D.; Yingying, Zhou

2014-01-01

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

[Effects of different fertilization modes on vegetable growth, fertilizer nitrogen utilization, and nitrogen loss from vegetable field].

PubMed

Huang, Dong-feng; Wang, Guo; Li, Wei-hua; Qiu, Xiao-xuan

2009-03-01

A field experiment with Chinese cabbage, water spinach, and three-colored amaranth cropped three times in one year was conducted to study the effects of seven fertilization modes, i.e., none fertilization, basal application of chemical fertilizers, 1/2 basal application and 1/2 top-dressing of chemical fertilizers, basal application of chemical fertilizers and dicyandiamide, 1/2 basal application and 1/2 top-dressing of chemical fertilizers and dicyandiamide, 1/2 basal application and 1/2 top-dressing of chemical fertilizers and organic manure, and basal application of organic manure, on the plant height, yield, nitrogen accumulation, and fertilizer nitrogen utilization of the vegetables, and the loss of NO3- -N and NH4+ -N from vegetable field under natural rainfall condition. The results showed that comparing with none fertilization, the fertilization modes '1/2 basal application and 1/2 top-dressing of chemical fertilizers and organic manure' and 'basal application of chemical fertilizers and dicyandiamide' improved the agronomic properties of test vegetables, increased their yields by 103%-219% and 93%-226%, and nitrogen accumulation by 153% -216% and 231%-320%, respectively, and enhanced fertilizer nitrogen utilization rate. They also decreased the surface runoff loss of NO3- -N and NH4+ -N by 48.1% and 46.5%, respectively, compared with the mode 'basal application of chemical fertilizers', and hence, reduced the risk of agricultural non-point pollution. Therefore, these two fertilization modes could be popularized in vegetable production.

Biobehavioral Development. From Cells to Selves.

ERIC Educational Resources Information Center

National Inst. of Child Health and Human Development (NIH), Bethesda, MD.

Key to the mission of the National Institute of Child Health and Human Development (NICHD) is answering fundamental questions about how a single fertilized cell eventually develops into a fully functional adult human being and how a multitude of genetic and environmental factors influence that process. This document details part of NICHD's…

The fertilization ability and developmental competence of bovine oocytes grown in vitro

PubMed Central

MAKITA, Miho; UEDA, Mayuko; MIYANO, Takashi

2016-01-01

In vitro growth culture systems for oocytes are being developed in several mammalian species. In these growth culture systems, in vitro grown oocytes usually have lower blastocyst formation than in vivo grown oocytes after in vitro fertilization. Furthermore, there have been a few reports that investigated the fertilization ability of in vitro grown oocytes in large animals. The purpose of this study was to investigate the fertilization process and developmental competence of bovine oocytes grown in vitro. Oocyte-granulosa cell complexes collected from bovine early antral follicles (0.4−0.7 mm in diameter) were cultured for growth with 17β-estradiol and androstenedione for 14 days and matured in vitro. These oocytes were then inseminated for 6 or 12 h, and further cultured for development up to 8 days in vitro. After growth culture, oocytes grew from 95 µm to around 120 µm and acquired maturation competence (79%). Although fertilization rates of in vitro grown oocytes were low after 6 h of insemination, 34% of in vitro grown oocytes fertilized normally after 12 h of insemination, having two polar bodies and two pronuclei with a sperm tail, and 22% of these oocytes developed into blastocysts after 8 days of culture. The fertilization and blastocyst formation rates were similar to those of in vivo grown oocytes. In addition, blastocyst cell numbers were also similar between in vitro and in vivo grown oocytes. In conclusion, in vitro grown bovine oocytes are similar to in vivo grown oocytes in fertilization ability and can develop into blastocysts. PMID:27151093

The fertilization ability and developmental competence of bovine oocytes grown in vitro.

PubMed

Makita, Miho; Ueda, Mayuko; Miyano, Takashi

2016-08-25

In vitro growth culture systems for oocytes are being developed in several mammalian species. In these growth culture systems, in vitro grown oocytes usually have lower blastocyst formation than in vivo grown oocytes after in vitro fertilization. Furthermore, there have been a few reports that investigated the fertilization ability of in vitro grown oocytes in large animals. The purpose of this study was to investigate the fertilization process and developmental competence of bovine oocytes grown in vitro. Oocyte-granulosa cell complexes collected from bovine early antral follicles (0.4-0.7 mm in diameter) were cultured for growth with 17β-estradiol and androstenedione for 14 days and matured in vitro. These oocytes were then inseminated for 6 or 12 h, and further cultured for development up to 8 days in vitro. After growth culture, oocytes grew from 95 µm to around 120 µm and acquired maturation competence (79%). Although fertilization rates of in vitro grown oocytes were low after 6 h of insemination, 34% of in vitro grown oocytes fertilized normally after 12 h of insemination, having two polar bodies and two pronuclei with a sperm tail, and 22% of these oocytes developed into blastocysts after 8 days of culture. The fertilization and blastocyst formation rates were similar to those of in vivo grown oocytes. In addition, blastocyst cell numbers were also similar between in vitro and in vivo grown oocytes. In conclusion, in vitro grown bovine oocytes are similar to in vivo grown oocytes in fertilization ability and can develop into blastocysts.

Fertilization and development of eggs of the South African clawed toad, Xenopus laevis, on sounding rockets in space

NASA Astrophysics Data System (ADS)

Ubbels, Geertje A.; Berendsen, Willem; Kerkvliet, Sonja; Narraway, Jenny

Egg rotation and centrifugation experiments strongly suggest a role for gravity in the determination of the spatial structure of amphibian embryos. Decisive experiments can only be made in Space. Eggs of Xenopus laevis, the South African clawed toad, were the first vertebrate eggs which were successfully fertilized on Sounding Rockets in Space. Unfixed, newly fertilized eggs survived reentry, and a reasonable number showed a seemingly normal gastrulation but died between gastrulation and neurulation. Only a few reached the larval stage, but these developed abnormally. In the future, we inted to test whether this abnormal morphogenesis is due to reentry perturbations, or due to a real microgravity effect, through perturbation of the reinitiation of meiosis and other processes, or started by later sperm penetration.

Fertilization and development of eggs of the South African clawed toad, Xenopus laevis, on sounding rockets in space.

PubMed

Ubbels, G A; Berendsen, W; Kerkvliet, S; Narraway, J

1992-01-01

Egg rotation and centrifugation experiments strongly suggest a role for gravity in the determination of the spatial structure of amphibian embryos. Decisive experiments can only be made in Space. Eggs of Xenopus laevis, the South African clawed toad, were the first vertebrate eggs which were successfully fertilized on Sounding Rockets in Space. Unfixed, newly fertilized eggs survived reentry, and a reasonable number showed a seemingly normal gastrulation but died between gastrulation and neurulation. Only a few reached the larval stage, but these developed abnormally. In the future, we intend to test whether this abnormal morphogenesis is due to reentry perturbations, or due to a real microgravity effect, through perturbation of the reinitiation of meiosis and other processes, or started by later sperm penetration.

Modifiable risk factors for impaired fertility in women: what nurse practitioners need to know.

PubMed

Kelly-Weeder, Susan; O'Connor, Alane

2006-06-01

To provide an overview of impaired fertility in childbearing-aged women, to review the current research on modifiable lifestyle risk factors implicated in its development, and to suggest strategies for nurse practitioners (NPs) to assist women in behavioral changes that will allow them to protect their fertility. Original research articles and comprehensive review articles identified through Medline, CINAHL, and OVID databases. Research has shown that advancing age, a history of a sexually transmitted infection and/or pelvic inflammatory disease, extremes of body weight, and tobacco and caffeine use are potentially modifiable risk factors in the development of impaired fertility. NPs must be aware of the link between these behaviors and the development of impaired fertility in order to assist women in preserving their fertility. Individual counseling, education, and community-wide education strategies are discussed.

Female Employment Reduces Fertility in Rural Senegal

PubMed Central

2015-01-01

Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities. PMID:25816301

Who fertilizes the forest?

Treesearch

Kevin T. Smith

2016-01-01

Tree fertilization is a common service provided by commercial arborists and landscapers. Customers and clients are familiar with fertilization from the care of house or garden plants. Any hardware or garden supply store has attractive packages of colored crystals or liquid solutions that promise rapid growth and abundant blossoms. This familiarity with fertilization of...

Expression analysis of fertilization/early embryogenesis-associated genes in Phalaenopsis orchids.

PubMed

Chen, Jhun-Chen; Wei, Miao-Ju; Fang, Su-Chiung

2016-10-02

One of the distinct reproductive programs in orchid species is pollination-triggered ovule development and megasporogenesis. During sexual reproduction, fertilization occurs days to months after pollination. The molecular mechanisms evolved to carry out this strategic reproductive program remain unclear. In the August issue of Plant Physiology 1 , we report comprehensive studies of comparative genome-wide gene expression in various reproductive tissues and the molecular events associated with developmental transitions unique to sexual reproduction of Phalaenopsis aphrodite. Transcriptional factors and signaling components whose expression is specifically enriched in interior ovary tissues when fertilization occurs and embryos start to develop have been identified. Here, we report verification of additional fertilization-associated genes, DOMAINS REARRANGED METHYLTRANSFERASE 1 (PaDRM1), CHROMOMETHYLTRANSFERASE 1 (PaCMT1), SU(VAR)3-9 RELATED PROTEIN 1 (PaSUVR1), INDOLE-3-ACETIC ACID inducible 30-like 1 (PaIAA30L1), and ETHYLENE INSENSITIVE 3-like 1 (PaEIN3L1), and discuss their potential roles in gametophyte development, epigenetic reprogramming, and hormone regulation during fertilization and establishment of embryo development in Phalaenopsis orchids.

Fertility Regulation in an Economic Crisis

PubMed Central

McKelvey, Christopher; Thomas, Duncan; Frankenberg, Elizabeth

2015-01-01

Substantial international aid is spent reducing the cost of contraception in developing countries, as part of a larger effort to reduce global fertility and increase investment per child worldwide. The importance for fertility behaviors of keeping contraceptive prices low, however, remains unclear. Targeting of subsidies and insufficient price variation have hindered prior attempts to estimate the effect of monetary and non-monetary contraceptive costs on fertility behavior. Using longitudinal survey data from the Indonesia Family Life Survey, we exploit dramatic variation in prices and incomes that was induced by the economic crisis in the late 1990s to pin down the effect of contraceptive availability and costs as well as household resources on contraceptive use and method choice. The results are unambiguous: monetary costs of contraceptives and levels of family economic resources have a very small (and well-determined) impact on contraceptive use and choice of method. PMID:25843969

Control of Maize Vegetative and Reproductive Development, Fertility, and rRNAs Silencing by HISTONE DEACETYLASE 108

PubMed Central

Forestan, Cristian; Farinati, Silvia; Rouster, Jacques; Lassagne, Hervé; Lauria, Massimiliano; Dal Ferro, Nicola; Varotto, Serena

2018-01-01

Histone deacetylases (HDACs) catalyze the removal of acetyl groups from acetylated histone tails that consequently interact more closely with DNA, leading to chromatin state refractory to transcription. Zea mays HDA108 belongs to the Rpd3/HDA1 HDAC family and is ubiquitously expressed during development. The newly isolated hda108/hda108 insertional mutant exhibited many developmental defects: significant reduction in plant height, alterations of shoot and leaf development, and alterations of inflorescence patterning and fertility. Western blot analyses and immunolocalization experiments revealed an evident increase in histone acetylation, accompanied by a marked reduction in H3K9 dimethylation, in mutant nuclei. The DNA methylation status, in the CHG sequence context, and the transcript level of ribosomal sequences were also affected in hda108 mutants, while enrichment in H3 and H4 acetylation characterizes both repetitive and nonrepetitive transcriptional up-regulated loci. RNA-Seq of both young leaf and anthers indicated that transcription factor expression is highly affected and that the pollen developmental program is disrupted in hda108 mutants. Crosses between hda108/hda108 and epiregulator mutants did not produce any double mutant progeny indicating possible genetic interactions of HDA108 with distinct epigenetic pathways. Our findings indicate that HDA108 is directly involved in regulation of maize development, fertility, and epigenetic regulation of genome activity. PMID:29382649

Estimating family planning program effects on U.S. fertility rates.

PubMed

Cutright, P; Jaffe, F S

1977-08-01

An evaluation was undertaken of the effects on U. S. fertility rates of the national family planning program. 1968-1969 family planning enrollment data were linked to 1970 census data in the same areas to derive an objective measure of the impact of organized clinical family planning programs on the 1969-70 fertility rates of subgroups of women defined by age, race, marital status, economic status, and racial composition of their area. Multivariate modelling was used to control for spurious effects of irrelevant variables. Results of the multivariate modelling show significant reductions of marital fertility among the low socioeconomic groups served by the program; no effects were exhibited by groups not served. Cumulative fertility of all groups, black and white, at all age and socioeconomic levels was affected by the program. A plausible explanation for these results lies in antecedent factors which led to the presence or absence of family planning clinics in any particular area in 1969 and its 1969 enrollment level. Communities more favorably disposed to provision of birth control services would have been more likely than other areas to apply for federal funding of family planning programs when it became available in the middle 1960s. Due to an earlier start, their programs were flourishing by 1969.

Fertilization and early embryonic development in heifers and lactating cows in summer and lactating and dry cows in winter.

PubMed

Sartori, R; Sartor-Bergfelt, R; Mertens, S A; Guenther, J N; Parrish, J J; Wiltbank, M C

2002-11-01

Two experiments in two seasons evaluated fertilization rate and embryonic development in dairy cattle. Experiment 1 (summer) compared lactating Holstein cows (n = 27; 97.3 +/- 4.1 d postpartum [dppl; 40.0 +/- 1.5 kg milk/d) to nulliparous heifers (n = 28; 11 to 17 mo old). Experiment 2 (winter) compared lactating cows (n = 27; 46.4 +/- 1.6 dpp; 45.9 +/- 1.4 kg milk/d) to dry cows (n = 26). Inseminations based on estrus included combined semen from four high-fertility bulls. Embryos and oocytes recovered 5 d after ovulation were evaluated for fertilization, embryo quality (1 = excellent to 5 = degenerate), nuclei/embryo, and accessory sperm. In experiment 1, 21 embryos and 17 unfertilized oocytes (UFO) were recovered from lactating cows versus 32 embryos and no UFO from heifers (55% vs. 100% fertilization). Embryos from lactating cows had inferior quality scores (3.8 +/- 0.4 vs. 2.2 +/- 0.3), fewer nuclei/embryo (19.3 +/- 3.7 vs. 36.8 +/- 3.0) but more accessory sperm (37.3 +/- 5.8 vs. 22.4 +/- 5.5/embryo) than embryos from heifers. Sperm were attached to 80% of UFO (17.8 +/- 12.1 sperm/UFO). In experiment 2, lactating cows yielded 36 embryos and 5 UFO versus 34 embryos and 4 UFO from dry cows (87.8 vs. 89.5% fertilization). Embryo quality from lactating cows was inferior to dry cows (3.1 +/- 0.3 vs. 2.2 +/- 0.3), but embryos had similar numbers of nuclei (27.2 +/- 2.7 vs. 30.6 +/- 2.1) and accessory sperm (42.0 +/- 9.4 vs. 36.5 +/- 6.3). From 53% of the flushings from lactating cows and 28% from dry cows, only nonviable embryos were collected. Thus, embryos of lactating dairy cows were detectably inferior to embryos from nonlactating females as early as 5 d after ovulation, with a surprisingly high percentage of nonviable embryos. In addition, fertilization rate was reduced only in summer, apparently due to an effect of heat stress on the oocyte.

National markets for organic waste-derived fertilizers and soil amendments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Logan, T.J.; Pierzynski, G.M.; Pepperman, R.E.

1995-12-31

The last decade has seen enormous growth in the U.S. in the recycling of organic waste materials like sewage sludge, manures, yard waste, solid waste and various industrial wastes. This has been prompted by real or perceived shortages of landfill capacity, state and federal regulations favoring beneficial use of organic wastes, and public support for recycling. Use of fertilizers and soil amendments derived from these wastes has been stimulated by favorable supply-side economics, a shift to organic/sustainable agriculture, and water quality concerns that favor slow-release nutrient sources. This paper summarizes the properties and beneficial use attributes of the various wastesmore » and their derived products, markets for these materials, and constraints/strategies for market penetration.« less

Race-Ethnic Differences in the Non-marital Fertility Rates in 2006-2010.

PubMed

Kim, Yujin; Raley, R Kelly

2015-02-01

Research in the 1980s pointed to the lower marriage rates of blacks as an important factor contributing to race differences in non-marital fertility. Our analyses update and extend this prior work to investigate whether cohabitation has become an important contributor to this variation. We use data from the 2006-2010 National Survey of Family Growth (NSFG) and to identify the relative contribution of population composition (i.e. percent sexually active single and percent cohabiting) versus rates (pregnancy rates, post-conception marriage rates) to race-ethnic variation in non-marital fertility rates (N=7,428). We find that the pregnancy rate among single (not cohabiting) women is the biggest contributor to race-ethnic variation in the non-marital fertility rate and that contraceptive use patterns among racial minorities explains the majority of the race-ethnic differences in pregnancy rates.

Aqueous and gaseous nitrogen losses induced by fertilizer application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu, C.; Maggi, F.; Riley, W.J.

2009-01-15

In recent years concern has grown over the contribution of nitrogen (N) fertilizer use to nitrate (NO{sub 3}{sup -}) water pollution and nitrous oxide (N{sub 2}O), nitric oxide (NO), and ammonia (NH{sub 3}) atmospheric pollution. Characterizing soil N effluxes is essential in developing a strategy to mitigate N leaching and emissions to the atmosphere. In this paper, a previously described and tested mechanistic N cycle model (TOUGHREACT-N) was successfully tested against additional observations of soil pH and N{sub 2}O emissions after fertilization and irrigation, and before plant emergence. We used TOUGHREACT-N to explain the significantly different N gas emissions andmore » nitrate leaching rates resulting from the different N fertilizer types, application methods, and soil properties. The N{sub 2}O emissions from NH{sub 4}{sup +}-N fertilizer were higher than from urea and NO{sub 3}{sup -}-N fertilizers in coarse-textured soils. This difference increased with decreases in fertilization application rate and increases in soil buffering capacity. In contrast to methods used to estimate global terrestrial gas emissions, we found strongly non-linear N{sub 2}O emissions as a function of fertilizer application rate and soil calcite content. Speciation of predicted gas N flux into N{sub 2}O and N{sub 2} depended on pH, fertilizer form, and soil properties. Our results highlighted the need to derive emission and leaching factors that account for fertilizer type, application method, and soil properties.« less

Slow release fertilizers in bareroot nurseries

Treesearch

J. G. Iyer; J. Dobrahner; B. Lowery; J. Vandettey

2002-01-01

Maintaining sufficient soil fertility in tree nurseries for good tree growth can be implemented by annually performing soil analyses and following a fertility maintenance program. Percentage recovery by trees of fertilizer applied indicates efficiency of fertilizer use. There is a wide variation in the recovery among the various fertilizer elements. Our research has...

Design and development of decentralized water and wastewater technologies: a combination of safe wastewater disposal and fertilizer production.

PubMed

Fach, S; Fuchs, S

2010-01-01

Modern wastewater treatment plants are often inappropriate for communities in developing countries. Such communities lack the funding, resources and skilled labour required to implement, operate, and maintain these plants. This research was conducted to investigate and establish an appropriate wastewater treatment system for the district of Gunung Kidul, Indonesia. Due to its lack of water during the dry season, this district is considered one of the poorest areas in the nation. First, wastewater was stored in septic tank units for a retention time of 26 days. Anaerobic conditions occurred, resulting in an 80% reduction of initial COD. The retained sludge was well stabilized with great potential, if dewatered, for reuse as fertilizer. Consequently, supernatant was separated for experiments consisting of lab scale aerobic sand filtering unit. Through filtration, further removals of COD (about 30%) and pathogens were achieved. Rich in nitrogen, the resulting effluent could be used for irrigation and soil conditioning. With faecal sludge and also a mixture of septic sludge and food waste, the hydrolysis stage of anaerobic digestion was examined. This paper discusses the laboratory findings in Karlsruhe and the design and implementation of a treatment system in Glompong, Indonesia.

Comprehensive proteomic analysis of bovine spermatozoa of varying fertility rates and identification of biomarkers associated with fertility.

PubMed

Peddinti, Divyaswetha; Nanduri, Bindu; Kaya, Abdullah; Feugang, Jean M; Burgess, Shane C; Memili, Erdogan

2008-02-22

Male infertility is a major problem for mammalian reproduction. However, molecular details including the underlying mechanisms of male fertility are still not known. A thorough understanding of these mechanisms is essential for obtaining consistently high reproductive efficiency and to ensure lower cost and time-loss by breeder. Using high and low fertility bull spermatozoa, here we employed differential detergent fractionation multidimensional protein identification technology (DDF-Mud PIT) and identified 125 putative biomarkers of fertility. We next used quantitative Systems Biology modeling and canonical protein interaction pathways and networks to show that high fertility spermatozoa differ from low fertility spermatozoa in four main ways. Compared to sperm from low fertility bulls, sperm from high fertility bulls have higher expression of proteins involved in: energy metabolism, cell communication, spermatogenesis, and cell motility. Our data also suggests a hypothesis that low fertility sperm DNA integrity may be compromised because cell cycle: G2/M DNA damage checkpoint regulation was most significant signaling pathway identified in low fertility spermatozoa. This is the first comprehensive description of the bovine spermatozoa proteome. Comparative proteomic analysis of high fertility and low fertility bulls, in the context of protein interaction networks identified putative molecular markers associated with high fertility phenotype.

Comprehensive proteomic analysis of bovine spermatozoa of varying fertility rates and identification of biomarkers associated with fertility

PubMed Central

Peddinti, Divyaswetha; Nanduri, Bindu; Kaya, Abdullah; Feugang, Jean M; Burgess, Shane C; Memili, Erdogan

2008-01-01

Background Male infertility is a major problem for mammalian reproduction. However, molecular details including the underlying mechanisms of male fertility are still not known. A thorough understanding of these mechanisms is essential for obtaining consistently high reproductive efficiency and to ensure lower cost and time-loss by breeder. Results Using high and low fertility bull spermatozoa, here we employed differential detergent fractionation multidimensional protein identification technology (DDF-Mud PIT) and identified 125 putative biomarkers of fertility. We next used quantitative Systems Biology modeling and canonical protein interaction pathways and networks to show that high fertility spermatozoa differ from low fertility spermatozoa in four main ways. Compared to sperm from low fertility bulls, sperm from high fertility bulls have higher expression of proteins involved in: energy metabolism, cell communication, spermatogenesis, and cell motility. Our data also suggests a hypothesis that low fertility sperm DNA integrity may be compromised because cell cycle: G2/M DNA damage checkpoint regulation was most significant signaling pathway identified in low fertility spermatozoa. Conclusion This is the first comprehensive description of the bovine spermatozoa proteome. Comparative proteomic analysis of high fertility and low fertility bulls, in the context of protein interaction networks identified putative molecular markers associated with high fertility phenotype. PMID:18294385

Energy in synthetic fertilizers and pesticides: Revisited. Final project report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhat, M.G.; English, B.C.; Turhollow, A.F.

1994-01-01

Agricultural chemicals that are derived from fossil-fuels are the major energy intensive inputs in agriculture. Growing scarcity of the world`s fossil resources stimulated research and development of energy-efficient technology for manufacturing these chemicals in the last decade. The purpose of this study is to revisit the energy requirements of major plant nutrients and pesticides. The data from manufacturers energy survey conducted by The Fertilizer Institute are used to estimate energy requirements of fertilizers. Energy estimates for pesticides are developed from consulting previously published literature. The impact of technical innovation in the fertilizer industry to US corn, cotton, soybean and wheatmore » producers is estimated in terms of energy-saving.« less

Low fertility awareness in United States reproductive-aged women and medical trainees: creation and validation of the Fertility & Infertility Treatment Knowledge Score (FIT-KS).

PubMed

Kudesia, Rashmi; Chernyak, Elizabeth; McAvey, Beth

2017-10-01

To create, validate, and use a fertility awareness survey based on current U.S. Cross-sectional study. Not applicable. Phase 1 included U.S. women ages 18-45; phase 2 included female medical students and obstetrics and gynecology trainees at two urban academic programs. Survey including demographics, the Fertility & Infertility Treatment Knowledge Score (FIT-KS) instrument, and General Nutrition Knowledge Questionnaire. Knowledge of natural fertility and infertility treatments. The FIT-KS was validated through detailed item and validity analyses. In phase 1, 127 women participated; their median age was 31 years, and 43.7% had children. Their mean FIT-KS score was 16.2 ± 3.5 (55.9% correct). In phase 2, 118 medical trainees participated; their median age was 25 years, and 12.4% had children. Their mean FIT-KS score was 18.8 ± 2.1 (64.9% correct), with year of training correlating to a higher score (r=0.40). Participant awareness regarding lifestyle factors varied, but it was particularly low regarding the effects of lubricants. The majority underestimated the spontaneous miscarriage rate and overestimated the fecundability of 40-year-old women. There was general overestimation of success rates for assisted reproductive technologies, particularly among medical trainees. The FIT-KS is validated to current U.S. data for use in both general and medical populations as a quick assessment of fertility knowledge. The knowledge gaps demonstrated in this study correlate with national trends in delayed childbearing and time to initiate treatment. For medical trainees, these results raise concerns about the quality of fertility counseling they may be able to offer patients. Greater educational outreach must be undertaken to enhance fertility awareness. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Carbon and nitrogen isotopic signatures and nitrogen profile to identify adulteration in organic fertilizers.

PubMed

Verenitch, Sergei; Mazumder, Asit

2012-08-29

Recently it has been shown that stable isotopes of nitrogen can be used to discriminate between organic and synthetic fertilizers, but the robustness of the approach is questionable. This work developed a comprehensive method that is far more robust in identifying an adulteration of organic nitrogen fertilizers. Organic fertilizers of various types (manures, composts, blood meal, bone meal, fish meal, products of poultry and plant productions, molasses and seaweed based, and others) available on the North American market were analyzed to reveal the most sensitive criteria as well as their quantitative ranges, which can be used in their authentication. Organic nitrogen fertilizers of known origins with a wide δ(15)N range between -0.55 and 28.85‰ (n = 1258) were characterized for C and N content, δ(13)C, δ(15)N, viscosity, pH, and nitrogen profile (urea, ammonia, organic N, water insoluble N, and NO3). A statistically significant data set of characterized unique organic nitrogen fertilizers (n = 335) of various known origins has been assembled. Deliberately adulterated samples of different types of organic fertilizers mixed with synthetic fertilizers at a wide range of proportions have been used to develop the quantitative critical characteristics of organic fertilizers as the key indicators of their adulteration. Statistical analysis based on the discriminant functions of the quantitative critical characteristics of organic nitrogen fertilizers from 14 different source materials revealed a very high average rate of correct classification. The developed methodology has been successfully used as a source identification tool for numerous commercial nitrogen fertilizers available on the North American market.

PTK2b function during fertilization of the mouse oocyte

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Jinping; McGinnis, Lynda K.; Carlton, Carol

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 fertilizationmore » 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.« less

Talent Development: Potential for Developing Nations.

ERIC Educational Resources Information Center

Harris, Carole Ruth

1993-01-01

A theoretical approach to talent development in emerging nations is proposed, based on principles of curricular intervention derived from qualitative research. Implementation of such a culturally appropriate curriculum in Ebeye, Marshall Islands, illustrates the approach. Adaptations to other cultures are suggested. (Author/DB)

Agricultural Exports and the Environment: A Cross-National Study of Fertilizer and Pesticide Consumption

ERIC Educational Resources Information Center

Longo, Stefano; York, Richard

2008-01-01

The mass consumption of agrochemicals, including manufactured fertilizers and pesticides, by industrialized agricultural systems worldwide threatens human health and the health of ecosystems. The production of these agricultural inputs is a highly energy- and capital-intensive process, and their application contributes to a variety of direct and…

An investment in children's health, nutrition and education is the foundation stone for all national development.

PubMed

Kalra, S

1991-01-01

A medical student at the Christian Medical College in Ludhiana, India, won first place in the First Annual Dr. S.M. Gupta Memorial Essay Contest with this essay on investing in the health, nutrition, and education of India's children. The health, nutrition, and education condition of India's children is substandard. 10% of infants die before their first birthday. 15% of children die before age 5. Many Indian children suffer from diarrhea and acute respiratory infections. Investment in immunization, oral rehydration therapy, hygiene, and health education would prevent many of these deaths and illnesses. Illness and death cost parents time, energy, and money. Children suffering from malnutrition and sickness cannot concentrate on learning. The state of today's children foretells the state of tomorrow's adults, work force, and leaders. Poor nutrition and health contribute to India's substandard economic productivity. India has 14% of the world's population, but produces only 1.2% of its gross national product. Even though India was the first country to have a national family planning program, its fertility and population growth rates are high. Investment in children's health would show parents the benefits of planning their families. It would also improve India's poor performance in sports and war as well as national prestige and socioeconomic development. The considerable number of illiterates reflect India's failure to invest in education. Females have a lower literacy rate than males. Girls in India suffer much discrimination. They receive less food, less medical care, less opportunities for education, and less recreation. National development depends on the active participation of girls. Prevention is the key: nourish the children, educate them, and keep them healthy.

Sub-national population policy: the case of North Sulawesi.

PubMed

Jones, G W

1989-04-01

Since the 1970s, Indonesia has placed increasing emphasis on the development of stronger planning capacity at the regional level; however, the concept of regional autonomy is still viewed with suspicion given Indonesia's history of regional separatist movements. This fact has implications for the need for national population policy to be formulated and implemented with a view toward the varying conditions faced by different provinces and regions. The author presents a case study of fertility, mortality, migration, urbanization, and the development of human capital in 1 Indonesian province--North Sulawesi--to illustrate that special characteristics and internal diversity can demand individualized responses by policy makers. In terms of these 5 areas, the following observations can be made about conditions in North Sulawesi: 1) mortality rates are already below the national average, although infant mortality remains unacceptably high; 2) fertility rates are also well below the national average and approaching replacement level without any aggressive family planning outreach activities, but there remains a need to identify the ultimate fertility target and the extent to which intervention is required; 3) there is little scope for absorbing transmigrants, but there are some major issues regarding population redistribution within the province; 4) although there are no large cities, the increasing dominance of Manado is a concern; and 5) the quality of education and an employment structure to match the well-educated labor force are more important than an expansion of these services. A central concern is the ability of North Sulawesi to prevent "brain drain" to Jakarta; however, the province's capacity to do so is dependent on decisions made in Jakarta about the allocation of revenue, regulations regarding the processing of copra and cloves, new air routes, and the extent of regional autonomy to be tolerated in decisions affecting provincial growth.

Protect Your Fertility

MedlinePlus

... your teens and early twenties can affect your fertility for years to come. This prevention guide was written by ... loss of testic- ulor size, see your doctor. Fertility is something that you ... approximately 40 percent of infertile couples, the male partner is ...

Economic development and family size.

PubMed

Rios, R J

1991-01-01

high school enrollment is added to per capita gross national product. Fertility declines in Latin America in the future will be dependent on economic development, educational advancement for women, and a reduction in rural population.

Impaired fertilizing ability of superoxide dismutase 1-deficient mouse sperm during in vitro fertilization.

PubMed

Tsunoda, Satoshi; Kawano, Natsuko; Miyado, Kenji; Kimura, Naoko; Fujii, Junichi

2012-11-01

The oxidative modification of gametes by a reactive oxygen species is a major deleterious factor that decreases the successful rate of in vitro fertilization. Superoxide dismutase 1 (SOD1) plays a pivotal role in antioxidation by scavenging the superoxide anion, and its deficiency causes infertility in female mice, but the significance of the enzyme in male mice remains unclear. In the present study, we characterized Sod1(-/-) (Sod1-KO) male reproductive organs and compiled the first report of the impaired fertilizing ability of Sod1-KO sperm in in vitro fertilization. Insemination of wild-type oocytes with Sod1-KO sperm exhibited lower rates of fertility compared with insemination by wild-type sperm. The low fertilizing ability found for Sod1-KO sperm was partially rescued by reductant 2-mercaptoethanol, which suggested the oxidative modification of sperm components. The numbers of motile and progressive sperm decreased during the in vitro fertilization process, and a decline in ATP content and elevation in lipid peroxidation occurred in the Sod1-KO sperm in an incubation time-dependent manner. Tyrosine phosphorylation, which is a hallmark for sperm capacitation, was also impaired in the Sod1-KO sperm. These results collectively suggest that machinery involved in sperm capacitation and motility are vulnerable to oxidative damage during the in vitro fertilization process, which could increase the rate of inefficient fertilization.

Ocean Fertilization and Ocean Acidification

NASA Astrophysics Data System (ADS)

Cao, L.; Caldeira, K.

2008-12-01

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

First line fertility treatment strategies regarding IUI and IVF require clinical evidence.

PubMed

Bahadur, G; Homburg, R; Muneer, A; Racich, P; Alangaden, T; Al-Habib, A; Okolo, S

2016-06-01

The advent of intracytoplasmic sperm injection (ICSI) has contributed to a significant growth in the delivery of assisted conception technique, such that IVF/ICSI procedures are now recommended over other interventions. Even the UK National Institute for Health Care Excellence (NICE) guidelines controversially recommends against intrauterine insemination (IUI) procedures in favour of IVF. We reflect on some of the clinical, economic, financial and ethical realities that have been used to selectively promote IVF over IUI, which is less intrusive and more patient friendly, obviates the need for embryo storage and has a global application. The evidence strongly favours IUI over IVF in selected couples and national funding strategies should include IUI treatment options. IUI, practised optimally as a first line treatment in up to six cycles, would also ease the pressures on public funds to allow the provision of up to three IVF cycles for couple who need it. Fertility clinics should also strive towards ISO15189 accreditation standards for basic semen diagnosis for male infertility used to triage ICSI treatment, to reduce the over-diagnosis of severe male factor infertility. Importantly, there is a need to develop global guidelines on inclusion policies for IVF/ICSI procedures. These suggestions are an ethically sound basis for constructing the provision of publicly funded fertility treatments. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fertility after breast cancer treatment.

PubMed

Kasum, Miro; Beketić-Orešković, Lidija; Peddi, Parvin F; Orešković, Slavko; Johnson, Rebecca H

2014-02-01

In many countries of the developed world, there is an increasing trend toward delay in childbearing from 30 to 40 years of age for various reasons. This is unfortunately concordant with an increasing incidence of breast cancer in women who have not yet completed their family. The current choice for premenopausal women with breast cancer is adjuvant therapy which includes cytotoxic chemotherapy, ovarian ablation (by surgery, irradiation, or chemical ovarian suppression), anti-estrogen therapy, or any combination of these. Although the use of adjuvant therapies with cytotoxic drugs can significantly reduce mortality, it raises issues of the long-term toxicity, such as induction of an early menopause and fertility impairment. The risk of infertility is a potential hardship to be faced by the patients following treatment of breast cancer. The offspring of patients who became pregnant after completion of chemotherapy have shown no adverse effects and congenital anomalies from the treatment, but sometimes high rates of abortion (29%) and premature deliveries with low birth weight (40%) have been demonstrated. Therefore, the issue of recent cytotoxic treatment remains controversial and further research is required to define a "safety period" between cessation of treatment and pregnancy. Preservation of fertility in breast cancer survivors of reproductive age has become an important issue regarding the quality of life. Currently, there are several potential options, including all available assisted technologies, such as in vitro fertilization and embryo transfer, in vitro maturation, oocyte and embryo cryopreservation, and cryopreservation of ovarian tissue. Because increased estrogen levels are thought to be potentially risky in breast cancer patients, recently developed ovarian stimulation protocols with the aromatase inhibitor letrozole and tamoxifen appear to provide safe stimulation with endogenous estrogen. Embryo cryopreservation seems to be the most established

Organic Biochar Based Fertilization

NASA Astrophysics Data System (ADS)

Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia

2017-04-01

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.

New fertilizer-producing system installed at Pad 39A

NASA Technical Reports Server (NTRS)

2000-01-01

A recently installed fertilizer-producing system sits near Launch Pad 39A. Using a 'scrubber,' the system captures nitrogen tetroxide vapor that develops as a by-product when it is transferred from ground storage tanks into the Shuttle storage tanks. Nitrogen tetroxide is used as the oxidizer for the hypergolic propellant in the Shuttle's on-orbit reaction control system. The scrubber then uses hydrogen peroxide to produce nitric acid, which, after adding potassium hydroxide, converts to potassium nitrate, a commercial fertilizer. Plans call for the resulting fertilizer to be used on the orange groves that KSC leases to outside companies.

Accumulation, availability, and uptake of heavy metals in a red soil after 22-year fertilization and cropping.

PubMed

Zhou, Shiwei; Liu, Jing; Xu, Minggang; Lv, Jialong; Sun, Nan

2015-10-01

Fertilization is important to increase crop yields, but long-term application of fertilizers probably aggravated the risk of heavy metals in acidic soils. In this study, the effect of 22-year fertilization and cropping on accumulation, availability, and uptake of heavy metals in red soil was investigated. The results showed that pig manure promoted significantly cadmium (Cd) accumulation (average 1.1 mg kg(-1)), nearly three times higher than national soil standards and, thus, increased metal availability. But the enrichment of heavy metals decreased remarkably by 50.5 % under manure fertilization, compared with CK (control without fertilization). On the contrary, chemical fertilizers increased greatly lead (Pb) availability and Cd activity; in particular, exceeding 85 % of soil Cd became available to plant under N (nitrogen) treatment during 9-16 years of fertilization, which correspondingly increased their enrichment by 29.5 %. Long-term application of chemical fertilizers caused soil acidification and manure fertilization led to the increase in soil pH, soil organic matter (SOM), and available phosphorus (Olsen P), which influenced strongly metal behavior in red soil, and their effect had extended to deeper soil layer (20∼40 cm). It is advisable to increase application of manure alone with low content of heavy metals or in combination with chemical fertilizers to acidic soils in order to reduce toxic metal risk.

TENORM: Fertilizer and Fertilizer Production Wastes

EPA Pesticide Factsheets

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).

Phosphorus in recycling fertilizers - analytical challenges.

PubMed

Krüger, Oliver; Adam, Christian

2017-05-01

The importance of secondary raw materials for phosphorus (P) fertilizer production is expected to increase in the future due to resource depletion, supply risks, and heavy metal contamination of fossil phosphate resources. Municipal wastewater is a promising source for P recovery. In Germany for instance, it contains almost 50% of the total amount of P that is currently applied as mineral fertilizer. Several procedures have been developed to recover and re-use P resulting in a growing number of recycling fertilizers that are currently not regulated in terms of fertilizer efficiency. We tested various materials and matrices for their total P content, solubility of P in neutral ammonium citrate (P nac ) and water, and performed robustness tests to check if existing analytical methods are suitable for those new materials. Digestion with inverse aqua regia was best suited to determine the total P content. P nac sample preparation and analyses were feasible for all matrices. However, we found significant time and temperature dependencies, especially for materials containing organic matter. Furthermore, several materials didn't reach equilibrium during the extractions. Thus, strict compliance of the test conditions is strongly recommended to achieve comparable results. Copyright © 2017 Elsevier Inc. All rights reserved.

Ethnicity and fertility in Nigeria.

PubMed

Kollehlon, Konia T

2003-01-01

Using a sample of Hausa-Fulani, Yoruba, Ibo, and all other women from the 1990 Nigerian Demographic and Health Survey, this study examines ethnic fertility differentials in Nigeria within the context of the social characteristics and cultural hypotheses. Among all women, we find the net fertility of Hausa-Fulani women to be lower than that of Other women; with no statistically significant difference in the net fertility of Ibo, Yourba, and Other women. But, among currently married women, we find the net fertility of Hausa-Fulani and Yoruba women to be lower than that of Other women, while the net fertility of Ibo women is higher than that of Other women. Overall, the findings of this study are more consistent with the cultural hypothesis, because statistically significant fertility differentials by ethnicity remain, even after controlling for selected socioeconomic and demographic variables.

Comparison of fertilization outcome between microdrop and open insemination methods in non-male factor IVF patients.

PubMed

Li, Yubin; Li, Tao; Mai, Qingyun; Long, Lingli; Ou, Jianping

2014-06-01

Both microdrop and open methods are commonly used for in vitro fertilization (IVF) protocols for embryo culture as well as oocyte insemination. However, few comparative studies evaluating the microdrop or open method of insemination on the fertilization outcome and subsequent embryo development have been performed. A randomized study was conducted to compare microdrop and open fertilization with respect to fertilization rate and embryo development among non-male factor patients undergoing in vitro fertilization and embryo transfer (IVF-ET). The results presented in this study demonstrate that the fertilization failure rate [total fertilization failure rate (TFF) plus low fertilization rate (<25% oocytes fertilized)] in the microdrop insemination group was higher than in the open insemination group (11.9% versus 3.3%, p < 0.001), while the good quality embryo rate and pregnancy rate did not differ significantly between the groups. As a highly complicated process involving many extrinsic and intrinsic factors, further studies are needed to confirm the effects of these insemination methods on the rate of fertilization failure.

Effects of the toxic benthic dinoflagellate Ostreopsis cf. ovata on fertilization and early development of the sea urchin Lytechinus variegatus.

PubMed

Neves, Raquel A F; Contins, Mariana; Nascimento, Silvia M

2018-04-01

Blooms of the benthic dinoflagellate Ostreopsis cf. ovata have been recorded with increasing frequency, intensity and geographic distribution. This dinoflagellate produces potent toxins that may cause mortality of marine invertebrates. Adults of sea urchins are commonly affected by O. cf. ovata exposure with evidence of spines loss and high mortality during periods of high dinoflagellate abundances. Here, we report on the effects of the toxic dinoflagellate O. cf. ovata on fertilization and early development of the sea urchin Lytechinus variegatus, a key ecological herbivore. Lytechinus variegatus eggs and sperm were experimentally exposed to different concentrations of Ostreopsis cf. ovata (4, 40, 400, and 4000 cells ml -1 ) to test the hypothesis that fertilization success, embryonic and larval development of the sea urchin are negatively affected by the toxic dinoflagellate even at low abundances. Reduced fertilization, developmental failures, embryo and larval mortality, and occurrence of abnormal offspring were evident after exposure to O. cf. ovata. Fertilization decreased when gametes were exposed to high O. cf. ovata abundances (400 and 4000 cells ml -1 ), but just the exposure to the highest abundance significantly reduced fertilization success. Sea urchin early development was affected by O. cf. ovata in a dose-dependent way, high dinoflagellate abundances fully inhibited the early development of L. variegatus. Ostreopsis cf. ovata significantly increased the mortality of sea urchin eggs and embryos in the first hours of exposure (∼1-3 h), regardless of dinoflagellate abundance. Abundances of 400 and 4000 O. cf. ovata cells ml -1 induced significantly higher mortality on sea urchin initial stages in the first hours, and no egg or embryo was found in these treatments after 18 h of incubation. The early echinopluteus larva was only reached in the control and in treatments with low Ostreopsis cf. ovata abundances (4 and 40 cells ml -1 ). The

Are Difficulties Balancing Work and Family Associated with Subsequent Fertility?

ERIC Educational Resources Information Center

Liu, Siwei; Hynes, Kathryn

2012-01-01

Despite considerable interest in the causes and consequences of work-family conflict, and the frequent suggestion in fertility research that difficulty in balancing work and family is one of the factors leading to low fertility rates in several developed countries, little research uses longitudinal data to examine whether women who report…

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

PubMed

Noble, J; Potts, M

1996-04-01

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

Fertilizer effects on attaining vegetation requirements.

DOT National Transportation Integrated Search

2014-02-01

This project was developed to evaluate the effects of varying the substrate and fertilization regimes on the success of complex warm-season grass and forb seedings on recent roadside construction sites. Re-vegetating construction projects is required...

A GIS-based fuzzy classification for mapping the agricultural soils for N-fertilizers use.

PubMed

Assimakopoulos, J H; Kalivas, D P; Kollias, V J

2003-06-20

Special attention should be paid to the choice of the proper N-fertilizer, in order to avoid a further acidification and degradation of acid soils and at the same time to improve nitrogen use efficiency and to limit the nitrate pollution of the ground waters. Therefore, the risk of leaching of the fertilizer and of the acidification of the soils must be considered prior to any N-fertilizer application. The application of N-fertilizers to the soil requires a good knowledge of the soil-fertilizer relationship, which those who are planning the fertilization policy and/or applying it might not have. In this study, a fuzzy classification methodology is presented for mapping the agricultural soils according to the kind and the rate of application of N-fertilizer that should be used. The values of pH, clay, sand and carbonates soil variables are estimated at each point of an area by applying geostatistical techniques. Using the pH values three fuzzy sets: "no-risk-acidification"; "low-risk-acidification"; and "high-risk-acidification" are produced and the memberships of each point to the three sets are estimated. Additionally, from the clay and sand values the membership grade to the fuzzy set "risk-of-leaching" is calculated. The parameters and their values, which are used for the construction of the fuzzy sets, are based on the literature, the existing knowledge and the experimentation, of the soil-fertilizer relationships and provide a consistent mechanism for mapping the soils according to the type of N-fertilizers that should be applied and the rate of applications. The maps produced can easily be interpreted and used by non-experts in the application of the fertilization policy at national, local and farm level. The methodology is presented through a case study using data from the Amfilochia area, west Greece.

7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.

Code of Federal Regulations, 2010 CFR

2010-01-01

... (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling... materials. (c) The producer must manage plant and animal materials to maintain or improve soil organic... fertility to maintain or improve soil organic matter content in a manner that does not contribute to...

Testis development, fertility, and survival in Ethanolamine kinase 2-deficient mice.

PubMed

Gustin, Sonja E; Western, Patrick S; McClive, Peter J; Harley, Vincent R; Koopman, Peter A; Sinclair, Andrew H

2008-12-01

Ethanolamine kinase 2 (Eki2) was previously isolated from a differential expression screen designed to identify candidate genes involved in testis development and differentiation. In mouse, Eki2 is specifically up-regulated in Sertoli cells of the developing testis at the time of sex determination. Based on this expression profile, Eki2 was considered a good candidate testis-determining gene. To investigate a possible role of Eki2 in testis development, we have generated a mouse with targeted disruption of the Eki2 gene by using an EGFP replacement strategy. No abnormalities were detected in the Eki2-deficient mice with regard to embryonic and adult testis morphology, differentiation, function, or fertility. Furthermore, no significant differences were observed in litter sizes, pup mortality rates, or distribution of the sexes among the offspring. Ethanolamine kinases are involved in the biosynthesis of phosphatidylethanolamine, a major membrane phospholipid. Expression analysis indicates that the absence of an apparent phenotype in the Eki2-deficient mice may be due to compensation by Eki2-family members or the activation of an alternative pathway to generate phosphatidylethanolamine. Expression of EGFP in this mouse model enabled the isolation of gonad cell populations, providing a useful resource from which to obtain relatively pure early steroidogenic cells for further studies.

Balancing Conservation with National Development: A Socio-Economic Case Study of the Alternatives to the Serengeti Road

PubMed Central

Hopcraft, J. Grant C.; Bigurube, Gerald; Lembeli, James Daudi; Borner, Markus

2015-01-01

Developing countries often have rich natural resources but poor infrastructure to capitalize on them, which leads to significant challenges in terms of balancing poverty alleviation with conservation. The underlying premise in development strategies is to increase the socio-economic welfare of the people while simultaneously ensuring environmental sustainability, however these objectives are often in direct conflict. National progress is dependent on developing infrastructure such as effective transportation networks, however roads can be ecologically catastrophic in terms of disrupting habitat connectivity and facilitating illegal activity. How can national development and conservation be balanced? The proposed Serengeti road epitomizes the conflict between poverty alleviation on one hand, and the conservation of a critical ecosystem on the other. We use the Serengeti as an exemplar case-study in which the relative economic and social benefits of a road can be assessed against the ecological impacts. Specifically, we compare three possible transportation routes and ask which route maximizes the socio-economic returns for the people while minimizing the ecological costs. The findings suggest that one route in particular that circumnavigates the Serengeti links the greatest number of small and medium sized entrepreneurial businesses to the largest labour force in the region. Furthermore, this route connects the most children to schools, provisions the greatest access to hospitals, and opens the most fertile crop and livestock production areas, and does not compromise the ecology and tourism revenue of the Serengeti. This route would improve Tanzania’s food security and self-reliance and would facilitate future infrastructure development which would not be possible if the road were to pass through the Serengeti. This case study provides a compelling example of how a detailed spatial analysis can balance the national objectives of poverty alleviation while

Balancing Conservation with National Development: A Socio-Economic Case Study of the Alternatives to the Serengeti Road.

PubMed

Hopcraft, J Grant C; Bigurube, Gerald; Lembeli, James Daudi; Borner, Markus

2015-01-01

Developing countries often have rich natural resources but poor infrastructure to capitalize on them, which leads to significant challenges in terms of balancing poverty alleviation with conservation. The underlying premise in development strategies is to increase the socio-economic welfare of the people while simultaneously ensuring environmental sustainability, however these objectives are often in direct conflict. National progress is dependent on developing infrastructure such as effective transportation networks, however roads can be ecologically catastrophic in terms of disrupting habitat connectivity and facilitating illegal activity. How can national development and conservation be balanced? The proposed Serengeti road epitomizes the conflict between poverty alleviation on one hand, and the conservation of a critical ecosystem on the other. We use the Serengeti as an exemplar case-study in which the relative economic and social benefits of a road can be assessed against the ecological impacts. Specifically, we compare three possible transportation routes and ask which route maximizes the socio-economic returns for the people while minimizing the ecological costs. The findings suggest that one route in particular that circumnavigates the Serengeti links the greatest number of small and medium sized entrepreneurial businesses to the largest labour force in the region. Furthermore, this route connects the most children to schools, provisions the greatest access to hospitals, and opens the most fertile crop and livestock production areas, and does not compromise the ecology and tourism revenue of the Serengeti. This route would improve Tanzania's food security and self-reliance and would facilitate future infrastructure development which would not be possible if the road were to pass through the Serengeti. This case study provides a compelling example of how a detailed spatial analysis can balance the national objectives of poverty alleviation while maintaining

Segregation for fertility and meiotic stability in novel Brassica allohexaploids.

PubMed

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

2017-04-01

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

Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group.

PubMed

Holton, Sara; Rowe, Heather; Kirkman, Maggie; Jordan, Lynne; McNamee, Kathleen; Bayly, Christine; McBain, John; Sinnott, Vikki; Fisher, Jane

2016-02-15

As part of research investigating the complexities of managing fertility in Australia, public opinions about how Australians manage their fertility were sought from women and men. To identify public opinion about sexual and reproductive health in Australia. To ensure access to a diverse group of people throughout Australia, an online group was advertised and convened on Facebook from October through December 2013. In a closed-group moderated discussion, participants responded to questions about how people in Australia attempt to manage three aspects of fertility: avoiding pregnancy, achieving pregnancy, and difficulties conceiving. Nonidentifiable demographic information was sought; no personal accounts of fertility management were requested. The discussion transcript was analyzed thematically. There were 61 female and 2 male Facebook users aged 18 to 50 years living in Australia participating in the study. Four main themes about fertility management were identified: access, geographical location, knowledge, and cost. Participants reported that young people and people from rural areas face barriers accessing contraception and fertility services. Limited knowledge about sex and reproduction and the cost of fertility services and contraception were also said to impede effective fertility management. Reasons for inequalities in effective fertility management that are amenable to change were identified. Facebook is an effective method for gaining insights into public opinion about sexual and reproductive health.

The Scientific Impact of Developing Nations.