WorldWideScience

Sample records for nonmarital fertility spatial

  1. Decomposing trends in nonmarital fertility among Latinas.

    Science.gov (United States)

    DeLeone, Felicia Yang; Lichter, Daniel T; Strawderman, Robert L

    2009-09-01

    For Latinos, high rates of nonmarital fertility reinforce economic inequality and slow the pace of social and economic incorporation into American society. Changes in the nonmarital fertility ratio--nonmarital births as a percentage of all births (NMFR)--among women aged 15-44 over the period 1994-2005 were partitioned into three components: changes in marital and in nonmarital fertility, and in the proportion of women who were married. Annual birth data were drawn from the national Natality Detail File, and population estimates were drawn from the Current Population Surveys. Analyses were conducted for blacks, whites and Latinas, as well as for selected subgroups of Latinas; differences in NMFRs between racial and ethnic groups were also calculated. NMFRs were largely unchanged between 1994 and 2002, and then began to rise; they averaged 43% for Latinas, 69% for blacks and 23% for whites over the study period. In 2005, 48% of births to Latinas were nonmarital. Most of the rise in Latinas' NMFR was linked to a decline in marriage. Among foreign-born Latinas, a six-percentage-point increase in the NMFR was due mostly to a rise in nonmarital fertility and a decline in marital fertility, which offset the beneficial effects of a rising marriage rate. The difference between Latinas' and whites' NMFRs was largely attributed to Latinas' higher nonmarital fertility, whereas the difference between blacks' and whites' NMFRs was driven mostly by lower marriage rates among blacks. Efforts to reduce out-of-wedlock childbearing among Latinas are needed, and programs should promote healthy marriages, especially among foreign-born Latinas.

  2. Comment: Distinguishing Cohort Effects from Age*Period Effects on Non-Marital Fertility

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    Martin, Steve

    2009-01-01

    In the article "Cohort Effects on Non-marital Fertility," in this issue of "Social Forces," Jean Stockard employs a novel strategy for disentangling cohort, period, and age effects on the non-marital fertility ratio. In a model with fixed-effect controls for age and for time period, the author documents evidence for three cohort-specific factors…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  5. Examining the antecedents of U.S. nonmarital fatherhood.

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    Carlson, Marcia J; VanOrman, Alicia G; Pilkauskas, Natasha V

    2013-08-01

    Despite the dramatic rise in U.S. nonmarital childbearing in recent decades, limited attention has been paid to factors affecting nonmarital fatherhood (beyond studies of young fathers). In this article, we use data from the 2002 National Survey of Family Growth and the National Longitudinal Survey of Youth 1979 cohort to examine the antecedents of nonmarital fatherhood, as compared to marital fatherhood. Overall, we find the strongest support across both data sets for education and race/ethnicity as key predictors of having a nonmarital first birth, consistent with prior literature about women's nonmarital childbearing and about men's early/teenage fatherhood. Education is inversely related to the risk of nonmarital fatherhood, and minority (especially black) men are much more likely to have a child outside of marriage than white men. We find little evidence that employment predicts nonmarital fertility, although it does strongly (and positively) predict marital fertility. High predicted earnings are also associated with a greater likelihood of marital childbearing but with a lower likelihood of nonmarital childbearing. Given the socioeconomic disadvantage associated with nonmarital fatherhood, this research suggests that nonmarital fatherhood may be an important aspect of growing U.S. inequality and stratification both within and across generations.

  6. Nonmarital Fertility, Union History, and Women's Wealth.

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    Painter, Matthew; Frech, Adrianne; Williams, Kristi

    2015-02-01

    We use more than 20 years of data from the National Longitudinal Survey of Youth 1979 to examine wealth trajectories among mothers following a nonmarital first birth. We compare wealth according to union type and union stability, and we distinguish partners by biological parentage of the firstborn child. Net of controls for education, race/ethnicity, and family background, single mothers who enter into stable marriages with either a biological father or stepfather experience significant wealth advantages over time (more than $2,500 per year) relative to those who marry and divorce, cohabit, or remain unpartnered. Sensitivity analyses adjusting for unequal selection into marriage support these findings and demonstrate that race (but not ethnicity) and age at first birth structure mothers' access to later marriage. We conclude that not all single mothers have equal access to marriage; however, marriage, union stability, and paternity have distinct roles for wealth accumulation following a nonmarital birth.

  7. Socioeconomic Variation in the Effect of Economic Conditions on Marriage and Nonmarital Fertility in the United States: Evidence From the Great Recession.

    Science.gov (United States)

    Schneider, Daniel; Hastings, Orestes P

    2015-12-01

    The United States has become increasingly characterized by stark class divides in family structure. Poor women are less likely to marry than their more affluent counterparts but are far more likely to have a birth outside of marriage. Recent theoretical and qualitative work at the intersection of demography and cultural sociology suggests that these patterns are generated because poor women have high, nearly unattainable, economic standards for marriage but make a much weaker connection between economic standing and fertility decisions. We use the events of the Great Recession, leveraging variation in the severity of the crisis between years and across states, to examine how exposure to worse state-level economic conditions is related to poor women's likelihood of marriage and of having a nonmarital birth between 2008 and 2012. In accord with theory, we find that women of low socioeconomic status (SES) exposed to worse economic conditions are indeed somewhat less likely to marry. However, we also find that unmarried low-SES women exposed to worse economic conditions significantly reduce their fertility; economic standing is not disconnected from nonmarital fertility. Our results suggest that economic concerns were connected to fertility decisions for low-SES unmarried women during the Great Recession.

  8. Cohabitation, nonmarital childbearing, and the marriage process

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    Kelly Musick

    2007-04-01

    Full Text Available Past work on the relationship between cohabitation and childbearing shows that cohabitation increases fertility compared to being single, and does so more for intended than unintended births. Most work in this area, however, does not address concerns that fertility and union formation are joint processes, and that failing to account for the joint nature of these decisions can bias estimates of cohabitation on childbearing. For example, cohabitors may be more likely to plan births because they see cohabitation as an acceptable context for childbearing; alternatively, they may be more likely to marry than their single counterparts. In this paper, I use a modeling approach that accounts for the stable, unobserved characteristics of women common to nonmarital fertility and union formation as a way of estimating the effect of cohabitation on nonmarital fertility net of cohabitors' potentially greater likelihood of marriage. I distinguish between intended and unintended fertility to better understand variation in the perceived acceptability of cohabitation as a setting for childbearing. I find that accounting for unmeasured heterogeneity reduces the estimated effect of cohabitation on intended childbearing outside of marriage by up to 50%, depending on race/ethnicity. These results speak to cohabitation's evolving place in the family system, suggesting that cohabitation may be a step on the way to marriage for some, but an end in itself for others.

  9. Non-marital cohabitation in the Republic of Serbia

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    Ranđelović Dragana

    2017-01-01

    Full Text Available Non-marital cohabitation, as a community of life of two people connected only by the feeling of love and desire for living together, without form and registration, is an institution as old as marriage. Throughout history, attitude of the legislator has been changing from forbidding to ignoring it. In our society there is a negative attitude towards non-marital cohabitations, which is the result of patriarchal ideas and customs. However, the Constitution of the Republic of Serbia and the Family Law equate marriage and non-marital cohabitation. In this paper, the author will try to determine to what extent in terms of effects the marital and non-marital cohabitation are equal, or to what extent the rights of non-marital partners are recognized. The subject of analysis are primarily the Constitution and Family law, but also many other regulations governing the issues relating to the rights and obligations of non-marital cohabitation partners. In fact, although Family law equalizes marriage and non-marital cohabitation, they are not equal either de facto or de jure. The author will try to point out the deficiencies in the legal regulations, the practical problems and suggest possible and better solutions.

  10. Neighborhood Poverty and Nonmarital Fertility: Spatial and Temporal Dimensions

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    South, Scott J.; Crowder, Kyle

    2010-01-01

    Data from 4,855 respondents to the Panel Study of Income Dynamics were used to examine spatial and temporal dimensions of the effect of neighborhood poverty on teenage premarital childbearing. Although high poverty in the immediate neighborhood increased the risk of becoming an unmarried parent, high poverty in surrounding neighborhoods reduced…

  11. The educational gradient of nonmarital childbearing in Europe: emergence of a pattern of disadvantage?

    OpenAIRE

    Perelli-Harris, B.; Sigle-Rushton, W.; Lappegard, T.; Kreyenfeld, M.; Keizer, R.; Berghammer, C.

    2010-01-01

    Nearly every European country has experienced some increase in nonmarital childbearing, largely due to increasing births within cohabitation. Relatively few studies in Europe, however, investigate the educational gradient of childbearing within cohabitation or how it changed over time. Using retrospective union and fertility histories, we employ competing risk hazard models to examine the educational gradient of childbearing in cohabitation in 8 countries across Europe. In all countries studi...

  12. [Characteristics of non-marital and non-commercial heterosexual transmission of HIV infection in Miao-Dong Autonomous prefecture of Qiandongnan].

    Science.gov (United States)

    Yu, Q Y; Wang, F L; Xu, P; Wen, H J; Xiong, Y X; Yang, J; Long, Y; He, H J; Shi, J; Lyu, P

    2017-11-06

    Objective: The goal of this research was to understand the demographic distribution and related factors of non-marital and non-commercial heterosexual transmission (non-commercial transmission) for HIV/AIDS (human immunodeficiency virus/acquired immunodeficiency syndrome). Methods: Data related to HIV/AIDS infected by non-marital heterosexual transmission and whose present address was in Qian Dongnan, were collected from Information System on the HIV/AIDS Prevention and Control. Information included demographic characteristics, the members of non-marital sex partners, transmission path, detection source, CD4(+)T lymphocyte level, et al. cases belong to homosexual history, injective drug use or non-classified non-marital heterosexuality transmission were excluded, totally collect HIV/AIDS 919 cases. Multivariate logistic regressions were used to analyze potential factors associated with non-marital and non-commercial heterosexual transmission. In addition, in March and June 2017, using a convenience sampling, we conducted one-to-one interviews among 10 HIV/AIDS who were infected by non-marital heterosexuality and had non-marital and non-commercial heterosexual experience in Kaili Center for Disease Control and Prevention. The content of the interview included basic information, sexual orientation, the main place of making friends and sexual behavior, attitude to commercial heterosexuality and non-martial and non-commercial heterosexuality and so on. Results: Out of the 919 cases, 645 (70.2%) were male, the proportion of non-commercial transmission was 55.06% (506). The proportion of female HIV/AIDS with non-commercial transmission was 84.7% (232), which was higher than male (42.5%(274)) (χ(2)=138.35, Pcommercial transmission was 61.5% (275), which was higher than other religion (52.2%(412)) (χ(2)=6.32, P= 0.012). The proportion of HIV/AIDS with non-commercial transmission who had 0-5 non-marital sexual partners was 58.8% (498), which was higher than who had>5 non-marital

  13. Proposed amendments to the legal proposition on establishment of non-marital paternity from 1855

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    Kulauzov Maša M.

    2015-01-01

    Full Text Available Proposed amendments to the article 130 of Serbian Civil Code (henceforth: SCC of 1844 regarding establishment of non-marital paternity were scrutinized in this paper. Originally, establishment of non-marital paternity was granted, but with significant restriction that presumed parent could have been declared the father of an illegitimate child only if he had recognized paternity. That is the reason why in 1855 the Supreme Court suggested amendment to the provision concerning determination of paternity. According to proposed modification, evidence that presumed father was on intimate terms with child's mother in the time of conception should have been sufficient for establishment of paternity. As non-marital relationships were condemned in patriarchal Serbian 19th century society, illegitimate children were considered a product of sin and family disgrace. Hence, the Ministry of Justice, the State Council and Prince Aleksandar Karađorđević were not interested in bettering their position by widening possibilities of determination of fatherhood. Subsequently, in 1868 the amendment was passed by which non-marital paternity could not have been established by a court order, subject to certain exceptions (if one raped or abducted a woman, and the time of conception coincided with the time of abduction or rape. Since 1868 paternity could have been determined solely subject to the consent, i.e. recognition of the illegitimate father.

  14. Pornography consumption and non-marital sexual behaviour in a sample of young Indonesian university students.

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    Hald, Gert Martin; Mulya, Teguh Wijaya

    2013-01-01

    Using a sample of Indonesian university students and a cross sectional design, this study investigated prevalence rates and patterns of pornography consumption in Indonesia, a religious, sexually conservative, Muslim-majority nation with strict anti-pornography laws. Further, the association between pornography consumption and common non-marital sexual behaviours was explored. The study found that in this sample, pornography is as widely and readily consumed as in comparable international studies predominantly utilising Western background samples from more sexually liberal and less religious countries with very few laws on pornography. Gender differences in patterns of pornography consumption were pronounced and comparable with findings in international counterpart studies. For men only, pornography consumption was found to significantly predict common sexual behaviours in non-marital relations. The study is the first to provide insights into prevalence rates and patterns of pornography consumption and its association with common non-marital sexual behaviours in a sexually conservative, Muslim-majority nation with strict anti-pornography laws.

  15. Modeling Spatial and Temporal Variability in Ammonia Emissions from Agricultural Fertilization

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    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

  16. Bulgaria: Ethnic differentials in rapidly declining fertility

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    Dimiter Philipov

    2008-07-01

    Full Text Available This chapter provides a detailed description of the fertility changes in Bulgaria during recent decades and discusses possible reasons and consequences. It also gives an overview of the steps that the government has undertaken to offset the considerable decline in fertility. Before the fall of communism, fertility trends in Bulgaria were stable and characterized by a nearly universal entry into parenthood, dominance of a two-child family model, an early start and early end of childbearing, stable mean ages at entry into childbearing and marriage, and low percentages of non-marital births. During the 1990s and in the first years of the new century, we observe a marked, rapid change in fertility behaviour. Together with the severe decline in overall fertility rates, demographic data reveal a significant postponement of entry into motherhood and marriage, a decline of the two-child family model, and an emergence of new family forms. Most research attributes these changes to the particular political and social situation in Bulgaria since 1989.

  17. Pornography consumption and non-marital sexual behaviour in a sample of young Indonesian university students

    DEFF Research Database (Denmark)

    Hald, Gert Martin; Mulya, Teguh Wijaya

    2013-01-01

    Using a sample of Indonesian university students and a cross sectional design, this study investigated prevalence rates and patterns of pornography consumption in Indonesia, a religious, sexually conservative, Muslim-majority nation with strict anti-pornography laws. Further, the association...... between pornography consumption and common non-marital sexual behaviours was explored. The study found that in this sample, pornography is as widely and readily consumed as in comparable international studies predominantly utilising Western background samples from more sexually liberal and less religious...... countries with very few laws on pornography. Gender differences in patterns of pornography consumption were pronounced and comparable with findings in international counterpart studies. For men only, pornography consumption was found to significantly predict common sexual behaviours in non-marital relations...

  18. The educational gradient of nonmarital childbearing in Europe : emergence of a pattern of disadvantage?

    NARCIS (Netherlands)

    Perelli-Harris, B.; Sigle-Rushton, W.; Lappegard, T.; Kreyenfeld, M.; Keizer, R.; Berghammer, C.

    2010-01-01

    Nearly every European country has experienced some increase in nonmarital childbearing, largely due to increasing births within cohabitation. Relatively few studies in Europe, however, investigate the educational gradient of childbearing within cohabitation or how it changed over time. Using

  19. Different places, different stories: A study of the spatial heterogeneity of county-level fertility in China

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    Donghui Wang

    2017-08-01

    Full Text Available Background: China has been characterized by persistently low fertility rates since the 1990s. Existing literature has examined the relationship between fertility levels and social, economic, and policy-related determinants. However, the possible spatial variation in these relationships has 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 socioeconomic and policy-related factors. Conclusions: We find that 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, fertility policy compliance ratio vary spatially in terms of direction, strength, and magnitude. This spatial variation is largely due to differences in local characteristics. The differences between and the complexities of localities cannot be told by a single story of either government intervention or socioeconomic development. Contribution: This study extends existing fertility research on China by explicitly recognizing the spatial heterogeneity in the impact 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 subnational level in China and other countries.

  20. Marital Quality and Divorce Decisions: How Do Premarital Cohabitation and Nonmarital Childbearing Matter?

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    Tach, Laura M.; Halpern-Meekin, Sarah

    2012-01-01

    This study used the 1979 cohort of the National Longitudinal Survey of Youth (N = 3,481) to test whether the association between marital quality and divorce is moderated by premarital cohabitation or nonmarital childbearing status. Prior research identified lower marital quality as a key explanation for why couples who cohabit or have children…

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

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    Henriette Engelhardt

    2008-07-01

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

  2. Lone mothers and their network support: Sociodemographic research of nonmarital parenthood in Serbia

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    Stanković Biljana

    2014-01-01

    Full Text Available The aim of this paper is to identify and describe the difficulties faced by families with nonmarital children (especially single-parent, available help and support, participation of the father in raising a child, and expected institutional help. That represents a first step toward better understanding of these families. The paper presents part of the results of research carried out in Belgrade with the aim of insight into the phenomenon of nonmarital childbearing at the individual level. It was conducted on a sample of 100 respondents, mothers of nonmarital children, who attend preschool. The survey was anonymous, carried out by the interview method. For this purpose a questionnaire with more than 50 questions was made, standardized to a great extent. In this paper, the focus is on the hardships and needs of the group of lone mothers. Though some issues take into account the answers of all respondents (21 cohabited mothers and 79 lone mothers, the analysis is largely related to the experiences and reflections of lone mothers. The 2011 Census data on prevalence of consensual unions and characteristics of persons living in them, as well as earlier data on the acknowledgment of paternity, do not indicate that nonmarital childbearing in Serbia takes place primarily in stable unions. It is realistic to assume that a large percentage of mothers with nonmarital children are lone mothers. The research results are generally consistent with the findings of relevant studies from our and foreign countries. As the largest difficulties, lone mothers emphasize financial problems, unemployment, housing difficulties, and child care, as well as a pronounced feeling of loneliness. Most of them in solving problems and rising children rely on their parents and siblings, with whom they often live in the same household. Every fifth lone mother when faced with a major problem, and every ninth in everyday raising a child can count on the father of the child. About a

  3. Exploring urban male non-marital sexual behaviours in Pakistan.

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    Mir, Ali M; Wajid, Abdul; Pearson, Stephen; Khan, Mumraiz; Masood, Irfan

    2013-04-11

    In Pakistan, sexual practices outside marriage are proscribed by law. We aimed to assess the range and magnitude of non-marital sexual behaviours of urban men, focusing on men having sex with men. In this cross sectional survey undertaken in six cities of Pakistan, we interviewed 2400 men aged 16-45 years selected through a multistage systematic sampling design. Sexual behaviours were assessed through a structured questionnaire. Multivariable analysis was used to identify association between various individual level characteristics and probability of engaging in sexual activities involving men. Nearly one-third (29 percent) reported having had non-marital sex in their lifetime. Of these men 16 percent reported premarital sex, while 11 percent reported engaging in both pre- and extramarital sex. Only two percent reported exclusive extramarital sex. In total 211 respondents, 9 percent reported ever having had sexual relations with men. While 62 respondents, 2.6 percent reported exclusive sex with males. Factors that were significantly associated with MSM behaviours were being less than 27 years (adjusted OR 5.4, 95% CI 3.8-7.7, p pornographic materials (adjusted OR 4.8, 95% CI 3.0-7.7, p pornographic materials (adjusted OR 3.3, 95% CI: 1.5-7.2, p = 0.002). To prevent the spread of STI's in Pakistan, preventive interventions should focus on reaching out to young uneducated men offering them with appropriate counselling and skills to adopt "safe sex practices" through workplace orientation sessions; while for youth in schools, life skills education be included in the curriculum. Through public-private partnership stigmatised groups should be reached through established community networks and provided with information on accessing voluntary counseling and treatment centres.

  4. Declining health disadvantage of non-marital children: Explanation of the trend in the Czech Republic 1990-2010

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    Martina Stipkova

    2013-10-01

    Full Text Available Background: There has been a rapid spread of non-marital childbearing in the Czech Republic during the last two decades. At the same time, the low birth weight rates of children born to married and unmarried mothers have converged. Objective: The goal is to explain the diminishing gap in low birth weight. Two explanations are assessed: the changing selection of unmarried mothers from disadvantaged socio-demographic groups, and increasing social support for unmarried mothers. Methods: Data from birth register are analysed. Marital status (married vs. unmarried disparities in low birth weight are modelled using logistic regression. Further analyses are then performed with a detailed measurement of partnership status. This detailed variable is partially missing and is thus supplemented with multiple imputation. Results: The main explanation for the narrowing gap between the outcomes of children born to married and unmarried mothers is the increasing social support for unmarried mothers. Unmarried motherhood has become less detrimental to a child's birth weight net of maternal demographic characteristics. The decline in selection from disadvantaged socio-demographic groups has also contributed to the convergence. However, the convergence of birth weight trends towards marital children seems to refer mostly to children of partnered mothers, with children of single mothers lagging behind. Conclusions: The positive trends in the health of non-marital children are interpreted as being the result of the increasing institutionalisation of parenthood in non-marital unions. However, this does not apply to unpartnered motherhood, which continues to represent a health disadvantage.

  5. The effect of neighbourhood mortality shocks on fertility preferences: a spatial econometric approach.

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    Owoo, Nkechi S; Agyei-Mensah, Samuel; Onuoha, Emily

    2015-07-01

    According to the demographic transition theory, fertility rates fall in response to declines in child mortality rates. Although national statistics indicate that child mortality rates have been declining over time, Ghana's fertility rates appear to have stalled. This paper hypothesises that women's fertility behaviours may be more responsive to child mortality experiences at more localised levels. Using all rounds of the Ghana Demographic and Health Surveys (1988-2008) and employing a variety of spatial and empirical estimation techniques, results indicate that in addition to own-child mortality, neighbourhood child mortality shocks are also a determinant of women's fertility in Ghana. Women in neighbourhoods with large child mortality shocks may desire more children as an "insurance" against future losses, as a result of their increased perceptions of own-child mortality risks.

  6. Reducing fertilizer-nitrogen losses from rowcrop landscapes: Insights and implications from a spatially explicit watershed model

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    McLellan, Eileen; Schilling, Keith; Robertson, Dale M.

    2015-01-01

    We present conceptual and quantitative models that predict changes in fertilizer-derived nitrogen delivery from rowcrop landscapes caused by agricultural conservation efforts implemented to reduce nutrient inputs and transport and increase nutrient retention in the landscape. To evaluate the relative importance of changes in the sources, transport, and sinks of fertilizer-derived nitrogen across a region, we use the spatially explicit SPAtially Referenced Regression On Watershed attributes watershed model to map the distribution, at the small watershed scale within the Upper Mississippi-Ohio River Basin (UMORB), of: (1) fertilizer inputs; (2) nutrient attenuation during delivery of those inputs to the UMORB outlet; and (3) nitrogen export from the UMORB outlet. Comparing these spatial distributions suggests that the amount of fertilizer input and degree of nutrient attenuation are both important in determining the extent of nitrogen export. From a management perspective, this means that agricultural conservation efforts to reduce nitrogen export would benefit by: (1) expanding their focus to include activities that restore and enhance nutrient processing in these highly altered landscapes; and (2) targeting specific types of best management practices to watersheds where they will be most valuable. Doing so successfully may result in a shift in current approaches to conservation planning, outreach, and funding.

  7. Nonmarital First Births, Marriage, and Income Inequality.

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    Cherlin, Andrew J; Ribar, David; Yasutake, Suzumi

    2016-08-01

    Many aggregate-level studies suggest a relationship between economic inequality and socio-demographic outcomes such as family formation, health, and mortality; but individual-level evidence is lacking. Nor is there satisfactory evidence on the mechanisms by which inequality may have an effect. We study the determinants of transitions to a nonmarital first birth as a single parent or as a cohabiting parent compared to transitions to marriage prior to a first birth among unmarried, childless young adults in the National Longitudinal Survey of Youth, 1997 cohort, from 1997 to 2011. We include measures of county-group-level household income inequality and of the availability of jobs typically held by high-school graduates and which pay above-poverty wages. We find that greater income inequality is associated with a reduced likelihood of transitioning to marriage prior to a first birth for both women and men. The association between levels of inequality and transitions to marriage can be partially accounted for by the availability of jobs of the type we measured. Some models also suggest that greater income inequality is associated with a reduced likelihood of transitioning to a first birth while cohabiting.

  8. Coparenting experiences in African American families: an examination of single mothers and their nonmarital coparents.

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    Gonzalez, Michelle; Jones, Deborah; Parent, Justin

    2014-03-01

    African American youth from single-mother homes continue to be overrepresented in statistics on risk behavior and delinquency, a trend that many be attributed to father-absence, socioeconomic disadvantage, and compromises in parenting more typical of single than two-parent families. Yet, this risk-focused perspective ignores a long-standing strength of the African American community, the involvement and potential protective impact of extended family members in childrearing. This study describes the experiences of 95 African American single mothers and their nonmarital coparents who participated in a study of African American single-mother families with an 11-16-year-old child. Specifically, the study examines: (a) the extent to which nonmarital coparents are involved in childrearing; (b) the relative levels of risk (i.e., depression, mother-coparent conflict) and protective (i.e., parenting) associated with maternal and coparent involvement; and (c) how similarly and/or differently coparent and mother variables operate with regard to youth externalizing problems. Findings reveal that a range of family members and other adults actively participate in childrearing in African American single-mother families, coparents do not differ from mothers on certain study variables (i.e., depression and mother-coparent conflict) but do for others (parenting), and coparent involvement is associated with youth adjustment in ways that are similar to our more established understanding of maternal involvement. The potential clinical implications of the findings are discussed and future research directions are highlighted. © 2014 FPI, Inc.

  9. Declining health disadvantage of non-marital children: Explanation of the trend in the Czech Republic 1990-2010

    OpenAIRE

    Martina Stipkova

    2013-01-01

    Background: There has been a rapid spread of non-marital childbearing in the Czech Republic during the last two decades. At the same time, the low birth weight rates of children born to married and unmarried mothers have converged. Objective: The goal is to explain the diminishing gap in low birth weight. Two explanations are assessed: the changing selection of unmarried mothers from disadvantaged socio-demographic groups, and increasing social support for unmarried mothers. Methods: Data fro...

  10. Coparenting Experiences in African American Families: An Examination of Single Mothers and their Non-Marital Coparents

    Science.gov (United States)

    Gonzalez, Michelle; Jones, Deborah J.; Parent, Justin

    2015-01-01

    African American youth from single mother homes continue to be overrepresented in statistics on risk behavior and delinquency, a trend that many be attributed to father-absence, socioeconomic disadvantage, and compromises in parenting more typical of single than two-parent families. Yet, this risk-focused perspective ignores a long-standing strength of the African American community, the involvement and potential protective impact of extended family members in childrearing. This study describes the experiences of 95 African American single mothers and their non-marital coparents who participated in a study of African American single mother families with an 11 to 16 year old child. Specifically, the study examines: 1) the extent to which nonmarital coparents are involved in childrearing; 2) the relative levels of risk (i.e., depression, mother-coparent conflict) and protective (i.e., parenting) associated with maternal and coparent involvement; and 3) how similarly and/or differently coparent and mother variables operate with regard to youth externalizing problems. Findings reveal that a range of family members and other adults actively participate in childrearing in African American single mother families, coparents do not differ from mothers on certain study variables (i.e., depression and mother-coparent conflict) but do for others (parenting), and coparent involvement is associated with youth adjustment in ways that are similar to our more established understanding of maternal involvement. The potential clinical implications of the findings are discussed and future research directions are highlighted. PMID:24479612

  11. The last decades and matrimonial changes.

    Science.gov (United States)

    Trost, J

    1992-01-01

    This paper focuses on changes in fertility, marriage patterns, cohabitation, divorce, and separation in Western European countries over the past few decades. Major trends discussed include the decline in fertility and marriage rates and the increase in nonmarital cohabitation, divorce, and separation.

  12. Nonmarital romantic relationship commitment and leave behavior: the mediating role of dissolution consideration.

    Science.gov (United States)

    Vanderdrift, Laura E; Agnew, Christopher R; Wilson, Juan E

    2009-09-01

    Two studies investigated the process by which individuals in nonmarital romantic relationships characterized by low commitment move toward enacting leave behaviors. Predictions based on the behavioral, goal, and implementation intention literatures were tested using a measure of dissolution consideration developed for this research. Dissolution consideration assesses how salient relationship termination is for an individual while one's relationship is intact. Study 1 developed and validated a measure of dissolution consideration and Study 2 was a longitudinal test of the utility of dissolution consideration in predicting the enactment of leave behaviors. Results indicated that dissolution consideration mediates the association between commitment and enacting leave behaviors, is associated with taking more immediate action, and provides unique explanatory power in leave behavior beyond the effect of commitment alone. Collectively, the findings suggest that dissolution consideration is an intermediate step between commitment and stay/leave behavior in close relationships.

  13. Germany: Family diversity with low actual and desired fertility

    Directory of Open Access Journals (Sweden)

    Jürgen Dorbritz

    2008-07-01

    Full Text Available Germany is a low-fertility country with a rapidly ageing population, and will remain so for the foreseeable future. There are several reasons for this trend. Germany is among the countries with the highest rates of childlessness in the world, and childlessness has become widely accepted. This is illustrated by changes in living arrangements. A broad range of living arrangements has been added to the basic model of marriage with children; namely, single living, non-marital cohabitation, lone parenthood, patchwork families and living apart together. A culture of individualism has spread in Germany which forms the basis for widespread decisions against family formation. The desired number of children has become low and family policy is considered to be a failure in terms of its influence on fertility. German family policy has had a traditional orientation centred on monetary support to families and on the promotion of the male breadwinner model. Women have been largely forced to choose between family and work, and leave the labour market when a child is born. The still prevailing concept of family policy does not help to reduce the pressure to choose between work and family life, and thus makes it easier to decide not to have children, especially for highly educated women. A change in family policy is needed which will enable couples to choose between the breadwinner-housewife and the reconciliation model. Gradually, this change is starting to take place.

  14. Nonmarital Fertility, Family Structure, and the Early School Achievement of Young Children from Different Race/Ethnic and Immigration Groups

    Science.gov (United States)

    Crosnoe, Robert; Wildsmith, Elizabeth

    2011-01-01

    Working from a life course perspective, this study examined the links between mothers' fertility and relationship statuses and children's early school achievement and how these links varied by race/ethnicity and immigration status. Analyses of nationally representative data from the Early Childhood Longitudinal Study-Kindergarten Cohort revealed…

  15. GIS Modelling for Site-Specific Nitrogen Fertilization towards Soil Sustainability

    Directory of Open Access Journals (Sweden)

    Antonis Papadopoulos

    2015-05-01

    Full Text Available Farmers need to make decisions that in most cases incorporate the concept of prediction and can hardly be revoked. One such decision is the application of fertilizing inputs. During past crop management and decision-making on fertilizing practices, many significant errors have been recorded, which have led and continue to lead to reduced production and environmental burden. The methodology followed in this paper involves the use of GIS, fuzzy logic and expert knowledge, in order to model physical processes associated with nitrogen balance in cultivated ecosystems and to evaluate the capabilities of or limitations on the use of certain fertilizers, based on spatial criteria. An original spatial decision support system was designed, developed and applied in a given study area. The system is composed of two modules (“fertilizing rate” and “fertilizing type”, making use of soil, climate and cultivation practices’ data, as recorded in the area of interest in quantitative or categorical form. The results of the application spatially classify the involved area according to its demand for nitrogen on the basis of the characteristics of each sub-region. The “fertilizing rate” module suggests reduced fertilizing doses of nitrogenous fertilizers compared to those already applied in the area. The system further divides the area into zones where specific types of fertilizers should be applied, giving a certain prescription for the method and time of application.

  16. An inventory of the emission of ammonia from agricultural fertilizer application in China for 2010 and its high-resolution spatial distribution

    NARCIS (Netherlands)

    Xu, Peng; Zhang, Yisheng; Gong, Weiwei; Hou, Xikang; Kroeze, Carolien; Gao, Wei; Luan, Shengji

    2015-01-01

    In an agricultural county like China, agricultural fertilizers are the source of ammonia (NH3) emissions. However, the spatial variability in NH3 emissions is large, and the associated uncertainties affect the reliability of total NH3 emission estimates. In this

  17. Diferenciace motivů svobodného mateřství: proč neprovdané matky nevstoupily před narozením svého prvního dítěte do manželství?

    Czech Academy of Sciences Publication Activity Database

    Chaloupková, Jana

    2007-01-01

    Roč. 1, č. 2 (2007), s. 127-140 ISSN 1802-8152 R&D Projects: GA AV ČR 1QS700280552 Institutional research plan: CEZ:AV0Z70280505 Keywords : motivation of un-married motherhood * non-marital fertility Subject RIV: AO - Sociology, Demography

  18. The pair correlation function of spatial Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Torrisi, Giovanni Luca

    2007-01-01

    Spatial Hawkes processes can be considered as spatial versions of classical Hawkes processes. We derive the pair correlation function of stationary spatial Hawkes processes and discuss the connection to the Bartlett spectrum and other summary statistics. Particularly, results for Gaussian fertility...... rates and the extension to spatial Hawkes processes with random fertility rates are discussed....

  19. The Impact of Soil Sampling Errors on Variable Rate Fertilization

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Hoskinson; R C. Rope; L G. Blackwood; R D. Lee; R K. Fink

    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 a 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 differences

  20. Educational differentials in cohabitors' marriage intentions at different childbearing stages in seven European countries.

    Science.gov (United States)

    Vergauwen, Jorik; Neels, Karel; Wood, Jonas

    2017-07-01

    Several studies have looked into the socio-economic gradients of cohabitation and non-marital fertility. According to the theory of the Second Demographic Transition, highly educated individuals can be considered as forerunners in the Western European spread of non-marital family forms after the 1970s. In Central and Eastern Europe (CEE), however, research has provided evidence for a Pattern of Disadvantage where those with the lowest education have been the most likely to adopt such family forms. Hitherto, few studies have considered the educational gradient of the intentions underlying these behaviors. This contribution uses information on marriage and fertility intentions from the Generations and Gender Surveys for seven European countries to assess educational differentials. In Western Europe we observe no strong educational gradients in marriage intentions at any childbearing stage (before, during or following). In CEE countries, however, less educated cohabitors more frequently choose for cohabitation during childbearing. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Spatial distribution of ammonium and calcium in optimally fertilized pine plantation soils

    Science.gov (United States)

    Ivan Edwards; Andrew Gillespie; Jennifer Chen; Kurt Johnsen; Ronald Turco

    2005-01-01

    Commercial timber production is increasingly reliant on long-term fertilization to maximize stand productivity, yet we do not understand the extent to which this practice homogenizes soil properties. The effects of 16 yr of optimal fertilization and optimal fertilization with irrigation (fertigation) on forest floor depth, pH, total organic carbon (TOC) and total...

  2. Child-Free and Unmarried: Changes in the Life Planning of Young East German Women

    Science.gov (United States)

    Adler, Marina A.

    2004-01-01

    Using evidence from demographic and survey data, this research examines how one decade of post-socialism has changed the life planning of young East German women. Aggregate data reflect marriage and fertility postponement and increased nonmarital birth rates and cohabitation. The analysis shows East German women's stubbornness (Dolling, 2003) in…

  3. How Are Women Doing?

    Science.gov (United States)

    Hacker, Andrew

    2002-01-01

    Reviews five books on how the politics of choice affects adoption, abortion, and welfare; Roe v. Wade; causes and consequences of nonmarital fertility; how misguided feminism harms young males; and the myth of frailty. Suggests that many of the issues raised will receive national notice if recent legislation requiring all states to test students…

  4. (ajst) pedological characteristics, general fertility

    African Journals Online (AJOL)

    Administrator

    Key words: Pedological characteristics, fertility, soil classification, benchmark soils, Morogoro. District, Tanzania ... rigorous soil mapping to show their spatial distribution. Although at the ... experience bimodal rainfall pattern characterized by two .... evaluated based on the standards set by EUROCONSULT ... crop growth.

  5. Temporal Changes in the Spatial Variability of Soil Nutrients

    Energy Technology Data Exchange (ETDEWEB)

    Hoskinson, Reed Louis; Hess, John Richard; Alessi, Randolph Samuel

    1999-07-01

    This paper reports the temporal changes in the spatial variability of soil nutrient concentrations across a field during the growing season, over a four-year period. This study is part of the Site-Specific Technologies for Agriculture (SST4Ag) precision farming research project at the INEEL. Uniform fertilization did not produce a uniform increase in fertility. During the growing season, several of the nutrients and micronutrients showed increases in concentration although no additional fertilization had occurred. Potato plant uptake did not explain all of these changes. Some soil micronutrient concentrations increased above levels considered detrimental to potatoes, but the plants did not show the effects in reduced yield. All the nutrients measured changed between the last sampling in the fall and the first sampling the next spring prior to fertilization. The soil microbial community may play a major role in the temporal changes in the spatial variability of soil nutrient concentrations. These temporal changes suggest potential impact when determining fertilizer recommendations, and when evaluating the results of spatially varying fertilizer application.

  6. Design and integration of components for site specific control of fertilizer application

    NARCIS (Netherlands)

    Bergeijk, van J.

    2001-01-01

    Keywords: Precision Agriculture, Site Specific Agriculture, Global Positioning System, GPS, Fertilizer Application, Information System.

    Spatial and temporal variability in soil, crop and climate characteristics results in non optimal use of fertilizers when the application

  7. Spatial patterns and determinants of fertility levels among women of ...

    African Journals Online (AJOL)

    Oluwayemisi O Alaba

    Nigeria record over six to seven children per woman.3 Among sub-Saharan ... woman's lifetime fertility.9 The data-collection method of the .... single, widowed or divorced. ..... change, economic growth, and poverty in the developing world.

  8. On the spatial diffusion of fertility decline: the distance-to-clinic variable in a Chilean community.

    Science.gov (United States)

    Fuller, G

    1974-10-01

    Survey data collected in San Gregorio, Chile during 1967 were selected for an investigation of the importance of residence distance-from-clinic in the pattern of contraceptive acceptance. Data were obtained through interviews conducted with women of fertile age who resided in every 4th house in the community. 1163 household reports could be employed. This number included a total of 1612 women in their fertile years. The 1612 women could be divided into users of some means of contraception and non-users. Once the basic binary classification procedure has been applied, each available socioeconomic variable for users and non-users may then be compared to determine if a significant difference exists among the distribution of the variables for each group. The variables of abortions, recent births, and aspiration level were the most potent discriminators between users and non-users of birth control. The more conventional socioeconomic variables showed little discriminatory power. Distance was found to be a fairly powerful discriminator between the group of users and non-users. Several variables other than distance are correlated with birth control practice, but once the influence of the spatial variation of these correlates has been extracted, distance emerges as the single most powerful discriminator between users and non-users of contraceptive techniques. There thus appears to be a need to emphasize the distribution of contraceptive supply in order to reduce the distance which women must travel to obtain birth control information or devices.

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

    Science.gov (United States)

    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" target="_blank">https://doi.org/10.1594/PANGAEA.883585.

  10. Age-varying associations between nonmarital sexual behavior and depressive symptoms across adolescence and young adulthood.

    Science.gov (United States)

    Vasilenko, Sara A

    2017-02-01

    Research has demonstrated associations between adolescent sexual behavior and depressive symptoms, but no single study has examined individuals at different ages throughout adolescence and young adulthood in order to determine at what ages sexual behavior may be associated with higher or lower levels of depressive symptoms. Using nationally representative longitudinal data and an innovative method, the time-varying effect model (TVEM), which examines how the strength of an association changes over time, this study examines how nonmarital sexual intercourse is associated with depressive symptoms at different ages, which behaviors and contexts may contribute to these associations, and whether associations differ for male and female participants. Findings indicate that sexual behavior in adolescence is associated with a higher level of depressive symptoms, particularly for female adolescents, and this association is relatively consistent across different partner types and adolescent contexts. Associations between sexual behavior and depressive symptoms in young adulthood are more dependent on partner factors and adolescent contexts; sexual behavior in young adulthood is associated with fewer depressive symptoms for women who have sex with a single partner and for men whose parents did not strongly disapprove of adolescent sexual behavior. Findings suggest that delaying sexual behavior into young adulthood may have some benefits for mental health, although contextual and relationship factors also play a role. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

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

    Science.gov (United States)

    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

  12. Patriarchy and fertility in Albania

    Directory of Open Access Journals (Sweden)

    Mathias Lerch

    2013-07-01

    Full Text Available BACKGROUND Theories of fertility collapse in the post-socialist era imply a decline in the moral primacy of traditional social institutions. Yet gender inequality actually increased in many countries, and there is a scarcity of empirical evidence for the role played by traditional social institutions in reproductive decision-making. OBJECTIVE We investigate whether patriarchal institutions sustained the fertility levels in Albania. The geography of marriage and family enlargement is related to the importance of patriarchy in kinship organisation and in the public sphere. To account for this spatial relationship we test the evidence for different pathways in patriarchal influence on reproductive decision-making including social effects, socialisation in patriarchal ideals, and the promotion of male fertility. METHODS We reconstruct reproductive histories from the 2001 Census and use data on attitudes and fertility intentions from the Reproductive and Health Survey 2002. Multilevel logistic regressions on marriage and (the intention of higher order births are used. RESULTS A majority of women endorsed patriarchal ideals and fertility transition was less advanced in more patriarchal municipalities. Patriarchal kinship organisation promoted early marriages and high fertility, which is shown to be achieved by social learning among peers and intergenerational social influences respectively, as well as by women's socialisation and a stopping behaviour in childbearing dominated by son-preference. Although gender inequality in the public sphere has also sustained the level of fertility and decreased the risk of marriage, it was not accounted for by these pathways of patriarchal influence. CONCLUSIONS Despite Albania's gradual opening to the world in a period of economic and political crisis, traditional social institutions remain important for family behaviours.

  13. Nonmarital romantic relationships and mental health in early adulthood: does the association differ for women and men?

    Science.gov (United States)

    Simon, Robin W; Barrett, Anne E

    2010-06-01

    Although social scientists have long assumed that intimate social relationships are more closely associated with women's than men's mental health, recent research indicates that there are no gender differences in the advantages of marriage and disadvantages of unmarried statuses when males' and females' distinct expressions of emotional distress are considered. These findings have led to the conclusion that there has been a convergence in the importance of intimate relationships for men's and women's mental health. However, these patterns may not be evident for nonmarital romantic relationships among current cohorts of young adults. In this article, we examine the associations among several dimensions of these relationships and symptoms of both depression and substance abuse/dependence in a diverse sample of young adults in Miami, Florida. We find gender differences that vary across dimensions of relationships: While current involvements and recent breakups are more closely associated with women's than men's mental health, support and strain in an ongoing relationship are more closely associated with men's than women's emotional well-being. Our findings highlight the need to consider the period in the life course as well as experiences of specific cohorts of men and women when theorizing about gender differences in the importance of intimate relationships for mental health.

  14. Fertility desires and fertility outcomes.

    Science.gov (United States)

    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

  15. The 2017 Fertilizer Emissions Airborne Study (FEAST): Quantifying N2O emissions from croplands and fertilizer plants in the Mississippi River Valley.

    Science.gov (United States)

    Kort, E. A.; Gvakharia, A.; Smith, M. L.; Conley, S.; Frauhammer, K.

    2017-12-01

    Nitrous Oxide (N2O) is a crucial atmospheric trace gas that drives 21st century stratospheric ozone depletion and substantively impacts climate. Anthropogenic emissions drive the global imbalance and annual growth of N2O, and the dominant anthropogenic source is fertilizer production and application, both of which have large uncertainties. In this presentation we will discuss the FEAST campaign, a study designed to demonstrate new approaches to quantify N2O emissions from fertilizer production and usage with aircraft measurements. In the FEAST campaign we deployed new instrumentation along with experienced flight sensors onboard the Scientific Aviation Mooney aircraft to make 40 hours of continuous 1Hz measurements of N2O, CO2, CO, H2O, CH4, O3, T, and winds. The Mississippi River Valley provided an optimal target as this location includes significant fertilizer production facilities as well as large cropland areas (dominated by corn, soy, rice, and cotton) with substantive fertilizer application. By leveraging our payload and unique airborne capabilities we directly observe and quantify N2O emissions from individual fertilizer production facilities (as well as CO2 and CH4 emissions from these same facilities). We are also able to quantify N2O fluxes from large cropland areas ( 100's km) employing a mass balance approach, a first for N2O, and will show results highlighting differences between crop types and amounts of applied fertilizer. The ability to quantify fluxes of croplands at 100km scale enables new understanding of processes controlling emissions at spatial scales that has eluded prior studies that either rely on extrapolation of small (flux chamber, towers), or work on 1,000+ km spatial scales (regional-global inversions from atmospheric measurements).

  16. Age-varying associations between non-marital sexual behavior and depressive symptoms across adolescence and young adulthood

    Science.gov (United States)

    Vasilenko, Sara A.

    2016-01-01

    Research has demonstrated associations between adolescent sexual behavior and depressive symptoms, but no single study has examined individuals at different ages throughout adolescence and young adulthood in order to determine at what ages sexual behavior may be associated with higher or lower levels of depressive symptoms. Using nationally representative longitudinal data and an innovative method, the time-varying effect model (TVEM), which examines how the strength of an association changes over time, this study examines how non-marital sexual intercourse is associated with depressive symptoms at different ages, which behaviors and contexts may contribute to these associations, and whether associations differ for male and female participants. Findings indicate that sexual behavior in adolescence is associated with a higher level of depressive symptoms, particularly for female adolescents, and this association is relatively consistent across different partner types and adolescent contexts. Associations between sexual behavior and depressive symptoms in young adulthood are more dependent on partner factors and adolescent contexts; sexual behavior in young adulthood is associated with fewer depressive symptoms for women who have sex with a single partner and for men whose parents did not strongly disapprove of adolescent sexual behavior. Findings suggest that delaying sexual behavior into young adulthood may have some benefits for mental health, although contextual and relationship factors also play a role. PMID:27854469

  17. The Decoupling of Marriage and Parenthood? Trends in the Timing of Marital First Births, 1945–2002

    Science.gov (United States)

    Hayford, Sarah R.; Guzzo, Karen Benjamin; Smock, Pamela J.

    2014-01-01

    Family formation changed dramatically over the twentieth century in the United States. The impact of these changes on childbearing has primarily been studied in terms of nonmarital fertility. However, changes in family formation behavior also have implications for fertility within marriage. We use data from ten fertility surveys to describe changes in the timing of marital childbearing from the 1940s through the 21st century for non-Hispanic white and non-Hispanic black women. Based on harmonized data from the Integrated Fertility Survey Series, our results suggest increasing divergence in fertility timing for white women. A growing proportion of marriages begin with a premarital conception; at the same time, an increasing proportion of white women are postponing fertility within marriage. For black women, marital fertility is increasingly postponed beyond the early years of marriage. Evaluating the sequencing of marriage and parenthood over time is critical to understanding the changing meaning of marriage. PMID:24791019

  18. Historical Agricultural Nitrogen Fertilizer Management in the Contiguous United States during 1850-2015.

    Science.gov (United States)

    Lu, C.; Cao, P.; Yu, Z.

    2017-12-01

    The United States has a century-long history of managing anthropogenic nitrogen (N) fertilizer to booster the crop production. Accurate characterization of N fertilizer use history could provide essential implications for N use efficiency (NUE) enhancement and N loss reduction. However, a spatially explicit time-series data remains lacking to describe how N fertilizer use varied among crop types, regions, and time periods. In this study, we therefore developed long-term gridded N management maps depicting N fertilizer application rate, timing, and ratio of fertilizer forms in nine major crops (i.e. corn, soybean, winter wheat, spring wheat, cotton, sorghum, rice, barley, and durum wheat) in the contiguous U.S. at a resolution of 1 km × 1 km during 1850-2015. We found that N application rates of the U.S. increased by approximately 34 times since 1940. Nonetheless, spatial analysis revealed that N-use hotspots have shifted from the West and Southeast to the Midwest and the Great Plains since 1900. Specifically, corn of the Corn Belt region received the most intensive N input in spring, followed by large N application amount in fall, implying a high N loss risk in this region. Moreover, spatiotemporal patterns of NH4+/NO3- ratio varied largely among regions. Generally, farmers have increasingly favored NH4+-form fertilizers over NO3- 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 the N addition impacts, and improve N management to alleviate environmental problems.

  19. Desired Fertility and Number of Children Born Across Time and Space.

    Science.gov (United States)

    Günther, Isabel; Harttgen, Kenneth

    2016-02-01

    Economists have often argued that high fertility rates are mainly driven by women's demand for children (and not by family planning efforts) with low levels of unwanted fertility across countries (and hence with little room for family planning efforts to reduce population growth). We study the relationship between wanted fertility and number of children born in a panel of 200 country-years controlling for country fixed effects and global time trends. In general, we find a close relationship between wanted and actual fertility, with one desired child leading to one additional birth. However, our results also indicate that in the last 20 years, the level of unwanted births has stayed at 2 across African countries but has, on average, decreased from 1 to close to 0 in other developing countries. Hence, women in African countries are less able to translate child preferences into birth outcomes than women in other developing countries, and forces other than fertility demand have been important for previous fertility declines in many developing countries. Family planning efforts only partially explain the observed temporal and spatial differences in achieving desired fertility levels.

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

    Science.gov (United States)

    Kolk, Martin; Cownden, Daniel; Enquist, Magnus

    2014-01-01

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

  1. Spatial variability of chemical properties of soil under pasture

    Directory of Open Access Journals (Sweden)

    Samuel Ferreira da Silva

    2016-04-01

    Full Text Available The objective of this study was to analyze the spatial variability of soil chemical attributes under pasture, as well as lime and fertilizer recommendations based on the interpretation of soil chemical analysis from two sampling methods: conventional and systematic depths of 0 to 10 and 10 to 20 cm. The study was conducted at IFES-campus Alegre-ES. Data analysis was performed using descriptive statistics and geostatistics. Results indicate that the spatial method enabled the identification of deficit areas and excessive liming and fertilization, which could not be defined by the conventional method.

  2. Millet response to water and soil fertility management in the Sahelian Niger : experiments and modeling

    OpenAIRE

    Akponikpe, Pierre

    2008-01-01

    In the 400-600 mm annual rainfall zone of the Sahel, soil fertility is the main determinant of yield in rainfed millet cropping systems in all but the driest years. Numerous on-farm and on-station experiments have addressed the issue of improving soil fertility. Yet the widespread use of the experimental results is restricted by the highly site specific millet response to fertility management practices due to high spatially variable soil properties as well as high intra- and inter-annual rain...

  3. Nano Fertilizers

    Directory of Open Access Journals (Sweden)

    Hatice DAĞHAN

    2017-06-01

    Full Text Available Agricultural land is decreasing day by day due to erosion, environmental pollution, unconscious irrigation and fertilization. On the other hand, it is necessary to increase agricultural production in order to meet the needs of the developing industry as well as the nutritional needs of the growing population. In the recent years, nano fertilizers have begun to be produced to obtain the highest amount and quality of production from the unit area. Previous research shows that nano fertilizers cause an increase in the use efficiency of plant nutrients, reduce soil toxicity, minimize the potential adverse effects of excessive chemical fertilizer use, and reduce fertilizer application frequency. Nano fertilizers are important in agriculture to increase crop yield and nutrient use efficiency, and to reduce excessive use ofchemical fertilizers. The most important properties of these fertilizers are that they contain one or more of macro and micronutrients, they can be applied frequently in small amounts and are environmentally friendly. However, when applied at high doses, they exhibit decreasing effects on plant growth and crop yields, similar to chemical fertilizers. In this review, the definition, importan ce, and classification of nano fertilizers, their application in plant production, advantages and disadvantages and the results obtained in this field were discussed.

  4. Unmanned Aerial Vehicle (UAV) data analysis for fertilization dose assessment

    Science.gov (United States)

    Kavvadias, Antonis; Psomiadis, Emmanouil; Chanioti, Maroulio; Tsitouras, Alexandros; Toulios, Leonidas; Dercas, Nicholas

    2017-10-01

    The growth rate monitoring of crops throughout their biological cycle is very important as it contributes to the achievement of a uniformly optimum production, a proper harvest planning, and reliable yield estimation. Fertilizer application often dramatically increases crop yields, but it is necessary to find out which is the ideal amount that has to be applied in the field. Remote sensing collects spatially dense information that may contribute to, or provide feedback about, fertilization management decisions. There is a potential goal to accurately predict the amount of fertilizer needed so as to attain an ideal crop yield without excessive use of fertilizers cause financial loss and negative environmental impacts. The comparison of the reflectance values at different wavelengths, utilizing suitable vegetation indices, is commonly used to determine plant vigor and growth. Unmanned Aerial Vehicles (UAVs) have several advantages; because they can be deployed quickly and repeatedly, they are flexible regarding flying height and timing of missions, and they can obtain very high-resolution imagery. In an experimental crop field in Eleftherio Larissa, Greece, different dose of pre-plant and in-season fertilization was applied in 27 plots. A total of 102 aerial photos in two flights were taken using an Unmanned Aerial Vehicle based on the scheduled fertilization. Α correlation of experimental fertilization with the change of vegetation indices values and with the increase of the vegetation cover rate during those days was made. The results of the analysis provide useful information regarding the vigor and crop growth rate performance of various doses of fertilization.

  5. Teen pregnancy: a public health issue or political football?

    Science.gov (United States)

    Clark, M P

    1996-08-01

    Politicians in the US have made adolescent parents the scapegoat of changing cultural patterns by suggesting punitive solutions to nonmarital births rather than addressing underlying causes of premature child-bearing. It is known that the percentages of young people of all races and all social classes reporting early, nonmarital sexual intercourse have increased dramatically, while adolescent fertility rates peaked in the 1950s. Improved access to contraception and abortion caused a decline in teen pregnancy and birth rates from 1970 to 1986. During 1986-91, service providers could not match growing demand, and the birth rate increased 25%. Increased rates of sexual activity have also led to increases in the incidence of sexually transmitted diseases (STDs) and HIV/AIDS among adolescents. This situation was exacerbated by Reagan and Bush policies, which reduced funding for services to adolescents and supported abstinence-only sex education courses. The concern voiced by policy-makers today centers on nonmarital childbearing by low-income adolescents who will rely on public assistance to survive. A proper response to this situation would involve the following policy actions: 1) mandating comprehensive sexuality education from kindergarten through high school, 2) funding mentoring programs, 3) improving economic and educational opportunities, 4) expanding STD and HIV/AIDS prevention programs, 5) increasing access to confidential health services (including mental health care and substance abuse treatment), 6) expanding child sexual abuse prevention and intervention programs, and 7) increasing access to and acceptability of teen contraceptive usage and abortion.

  6. A spatially based field specific crop recordkeeping system prototype ...

    African Journals Online (AJOL)

    These spatial data were prepared using ArcGIS 9.3. A database was created in Microsoft Access 2007. The database contained information on crops, fertilizers and past management. The information was linked to the spatial data table and maintained in the database. An application was developed using Visual Basic 6 in ...

  7. Cancer and fertility: strategies to preserve fertility.

    Science.gov (United States)

    Diedrich, K; Fauser, B C J M; Devroey, P

    2011-03-01

    Fertility preservation is a key component of cancer management in young people. The Fourth Evian Annual Reproduction Workshop Meeting was held in April 2009 to discuss cancer and fertility in young adults. Specialists in oncology, assisted reproduction, embryology and clinical genetics presented published data and ongoing research on cancer and fertility, with particular focus on strategies to preserve fertility. This report is based on the expert presentations and group discussions, supplemented with publications from literature searches and the authors' knowledge. Fertility preservation should be considered for all young people undergoing potentially gonadotoxic cancer treatment. A variety of options are required to facilitate safe and effective fertility preservation for individual patients. Sperm banking is a simple and low-cost intervention. Embryo cryopreservation is the only established method of female fertility preservation. Oocyte cryopreservation offers a useful option for women without a male partner. Emergency ovarian stimulation and cryopreservation of ovarian tissue (followed by tissue transplantation or in-vitro maturation of oocytes) are experimental techniques for women who require urgent cancer treatment. Further prospective studies are required to validate cryopreservation of oocytes and ovarian tissue, in-vitro maturation of oocytes and new vitrification techniques and to identify any long-term sequelae of slow freezing of embryos. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

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

    Data.gov (United States)

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

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

    Data.gov (United States)

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

  10. Educational differentials in cohort fertility during the fertility transition in South Korea

    Directory of Open Access Journals (Sweden)

    Sam Hyun Yoo

    2014-05-01

    Full Text Available Background: While there has been a considerable amount of research on the association between women's education and fertility rates, few of these studies have examined the pattern of fertility differentials over the course of the fertility transition. As a country that has experienced a rapid decline in fertility and marked improvements in women's educational attainment over the last several decades, South Korea represents an ideal case for studying this dynamic association. Objective: The aim of the article is to explain the pattern of fertility differentials by level of education and the contribution of the changes in women's educational attainment to the fertility decline during the fertility transition in South Korea. Methods: Drawing upon data from the Korean censuses conducted between 1970 and 2010, I analyze completed cohort fertility for women born between 1926 and 1970 using demographic-decomposition techniques and cohort parity progression ratios by level of education. Results: The differences in fertility by educational attainment have gradually declined over the transition, with fertility almost converging at a low level among recent birth cohorts. Fertility in South Korea had been declining in all of the social groups until the sub-replacement fertility was reached. The change in women's educational attainment then became an important factor in the further decline in fertility. The trend toward fewer children quickly spread from the most educated to the least educated women throughout the fertility transition. Conclusions: The transformation of fertility behaviors across social strata has been a key element in the Korean fertility transition. Although educational expansion, particularly the introduction of mass education, has contributed to falling fertility in South Korea, the role of education in fertility decline is more pronounced in the diffusion of innovative ideas and behaviors, which reduced fertility differentials across

  11. Effect of Various Organic Fertilizers Substitute Chemical Fertilizer on Cucumber Productions

    International Nuclear Information System (INIS)

    Piadang, Nattayana; Ratanapanit, Sittisuk; Chaowanklang, Pratuang; Ratanapanit; Nadtinee; Jaipakdee, Putinee; Ongsakitboriboon

    2006-09-01

    The effect of using the various organic fertilizer to substitute on the chemical fertilizer on cucumber, was carried out at Tambol Pattananikom, Amphur Pattananikom, Lopburi, Thailand, from December 1, 2005 to February 1, 2006 By using Randomized Comp let Block Design (RCBD), Contain with 4 treatments, chemical fertilizer: 16-16-16: 40 Kg/rai (Control), Pillet organic fertilizer: 50 Kg/rai, Bio extract from cow milk: 300 cc./ water 20 Ltr,.+ compost mixed in soil and bio fertilizer from the office of Atomic Energy Peace : 300 cc./water 20 Ltr. + campost mixed in soil (15 m. 2 /plot) were compared. Experiment result indicate that there were no significant differences on the yield. The highest yield of 25.91 kg/plot (27663.73 kg/rai) was obtained from chemical fertilizer, Fertilizer, followed by pillet organic fertilizer 22.88 kg/plot (2440.53 kg/rai), bio fertilizer 22.34 kg/pot (2382.93 kg/rai) and bio extract 19.03 kg/plot) (2029.87 kg/rai.

  12. Young female cancer patients' experiences with fertility counselling and fertility preservation

    DEFF Research Database (Denmark)

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

    2016-01-01

    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......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...

  13. Unrealized fertility: Fertility desires at the end of the reproductive career

    Directory of Open Access Journals (Sweden)

    John Casterline

    2017-01-01

    Full Text Available Background: 'Unrealized fertility' is a failure to achieve desired fertility. Unrealized fertility has been examined in low-fertility societies but, with the exception of research on infertility, has been neglected in research on non-Western societies. Objective: We conduct a multicountry investigation of one form of unrealized fertility, namely a reproductive career which ends with the woman desiring further children. Methods: We analyze 295,854 women aged 44‒48 in 252 surveys (DHS, RHS, PAP conducted in the period 1986-2015 in 78 countries. Two indicators of unrealized fertility are constructed: (i a comparison of ideal versus actual number of children; (ii the desire for another child. We estimate multilevel regressions with covariates at individual and aggregate levels. Results: Unrealized fertility is far more prevalent according to the first indicator than the second. It is more common among women with fewer living children and women whose first birth occurs after age 20, and it is distinctly higher in sub-Saharan Africa and lower in South Asia. The evidence on trend over the course of fertility transition is mixed: for the second indicator but not the first, the net effect is a reduction in the prevalence of unrealized fertility as fertility declines. Conclusions: Unrealized fertility occurs frequently in most societies and therefore deserves more rigorous research, especially on its consequences for emotional, social, economic, and demographic outcomes. Contribution: We provide the first comprehensive documentation of the prevalence of unrealized fertility across a broad set of contemporary non-Western societies.

  14. Second order analysis for spatial Hawkes processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Torrisi, Giovanni Luca

    We derive summary statistics for stationary Hawkes processes which can be considered as spatial versions of classical Hawkes processes. Particularly, we derive the intensity, the pair correlation function and the Bartlett spectrum. Our results for Gaussian fertility rates and the extension...... to marked Hawkes processes are discussed....

  15. Assessing yield and fertilizer response in heterogeneous smallholder fields with UAVs and satellites

    NARCIS (Netherlands)

    Schut, Antonius G.T.; Traore, Pierre C.S.; Blaes, Xavier; By, de Rolf A.

    2018-01-01

    Agricultural intensification and efficient use and targeting of fertilizer inputs on smallholder farms is key to sustainably improve food security. The objective of this paper is to demonstrate how high-resolution satellite and unmanned aerial vehicle (UAV) images can be used to assess the spatial

  16. Fate of 15N fertilizer applied to trickle-irrigated grapevines

    International Nuclear Information System (INIS)

    Hajrasuliha, S.; Rolston, D.E.; Louie, D.T.

    1998-01-01

    Information on fate of nitrogen applied to vines is needed to improve fertilizer management. Nitrogen-15 enriched ammonium and nitrate fertilizers were applied in the spring through a trickle irrigation system to six Thompson Seedless vines of a vineyard on the West Side of the San Joaquin Valley of California. At fruit harvest, all above-ground plant parts were removed and analyzed for 15 N. Soil around each vine was also sampled and analyzed for 15 N in the inorganic and organic N fractions. Spatial patterns of fertilizer N for soil inorganic and organic N were analyzed using a median polish technique which indicated large variability with respect to direction, distance, and depth. There was a tendency for the fertilizer N from NH 4 to be located directly beneath emitters than from the NO 3 . Nitrogen from the NH 4 application penetrated to only the 150-cm depth, whereas some N from the NO 3 application reached 210 to 240 cm. Most of the organic fertilizer N for both NO 3 and NH 4 applications was in the top 60 cm of soil where the vine roots were likely of greatest density. Overall recovery of fertilizer N was also quite variable, probably due to variability in soil physical properties and uneven surface application of water and fertilizer due to local surface ponding. Although not statistically significant, uptake of fertilizer N by above-ground plant components was slightly higher for the NH 4 application (24.2% of applied N) than the NO 3 application (21.5%). Soil organic N had significantly (95% level) higher N from NH 4 (19% of applied N) than from NO 3 (13%). This probably occurred due to longer residence time of N from NH 4 within the top 60 cm, where the bulk of roots and microbial activity existed, than for NO 3 . Overall, about 67% to 79% of the fertilizer N applied in spring remained in the soil at harvest, and the vines took up the rest. There was no indication of significant N leaching below 2.4 m or denitrification of fertilizer N for the trickle

  17. Cohort fertility decline in low fertility countries: Decomposition using parity progression ratios

    Directory of Open Access Journals (Sweden)

    Krystof Zeman

    2018-02-01

    Full Text Available Background: The long-term decline in cohort fertility in highly developed countries has been widely documented. However, no systematic analysis has investigated which parity contributed most to the fertility decline to low and very low levels. Objective: We examine how the contribution of changing parity progression ratios varied across cohorts, countries, and broader regions in Europe, North America, Australia, and East Asia. We pay special attention to countries that reached very low completed cohort fertility, below 1.75 children per woman. Methods: Using population censuses and large-scale surveys for 32 low fertility countries, we decompose the change in completed cohort fertility among women born between 1940 and 1970. The decomposition method takes into account the sequential nature of childbearing as a chain of transitions from lower to higher parities. Results: Among women born between 1940 and 1955, the fertility decline was mostly driven by reductions in the progression ratios to third and higher-order births. By contrast, among women born between 1955 and 1970, changes in fertility showed distinct regional patterns: in Central and Eastern Europe they were fuelled by falling second-birth rates, whereas in the German-speaking countries, Southern Europe, and East Asia decreases in first-birth rates played the major role. Conclusions: Pathways to low and very low fertility show distinct geographical patterns, which reflect the diversity of the cultural, socioeconomic, and institutional settings of low fertility countries. Contribution: Our study highlights the importance of analysing parity-specific components of fertility in order to understand fertility change and variation. We demonstrate that similar low levels of completed cohort fertility can result from different combinations of parity-specific fertility rates.

  18. Fertilization effects on the electrical conductivity measured by EMI, ERT, and GPR

    Science.gov (United States)

    Weihermueller, L.; Kaufmann, M.; Steinberger, P.; Pätzold, S.; Vereecken, H.; Van Der Kruk, J.

    2017-12-01

    Near surface geophysics such as electromagnetic induction (EMI), electrical resistivity tomography (ERT), and ground penetrating radar (GPR) are widely used for field characterization, to delineate soil units, and to estimate soil texture, bulk densities and/or soil water contents. Hereby, the measured soil apparent conductivity (ECa) is often used. Soil ECa is governed by horizontal and vertical changes in soil texture, mineralogy, soil water content, and temperature, and the single contributions are not easy to disentangle. Within single fields and between fields fertilization management may vary spatially, which holds especially for field trials. As a result, ECa might vary due to differences in electrolyte concentration and subsequent pore fluid conductivity, but secondary fertilization effects might also play a major role in ECa differences such as differences in soil water uptake by growing plants. To study the direct effect of mineral fertilization on ECa, a field experiment was performed on 21 bare soil plots each of a size of 9 m2, where 7 different fertilization treatments were established in triplicates. As mineral fertilizers, commercial calcium ammonium nitrate and potassium chloride were chosen and applied in dosages of 200, 400, and 2000 kg ha-1 N equivalent. Additionally, soil water, soil temperature, and EC were recorded in a pit at different depths using commercial sensors. Changes in ECa were measured every 10 days using EMI and monthly using GPR and ERT. Additionally, soil samples were monthly taken at all plots and nitrate, chloride, and potassium contents were measured in the lab. The poster will show the effect of ECa changes due to fertilization and corresponding leaching of the fertilized elements over time. The experimental results provide information of how fertilization is influencing ECa readings and how long the fertilizers are influencing ECa measurements with geophysical instruments. This study helps to overcome restricted

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

    Science.gov (United States)

    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

  20. [Regional difference of NPK fertilizers application and environmental risk assessment in Jiangsu Province, China].

    Science.gov (United States)

    Liu, Qin-pu

    2015-05-01

    It is of great importance to have a deep understanding of the spatial distribution of NPK fertilizers application and the potential threat to the ecological environment in Jiangsu Province, which is helpful for regulating the rational fertilization, strengthening the fertilizer use risk management and guidance, and preventing agricultural non-point pollution. Based on the environmental risk assessment model with consideration of different impacts of N, P, K fertilizers on environment, this paper researched the regional differentiation characteristic and environmental risk of intensity of NPK fertilizer usages in Jiangsu. Analystic hierarchy process ( AHP) was used to determine the weithts of N, P, K. The environmental safety thresholds of N, P, K were made according to the standard of 250 kg · hm(-2) for the construction of ecological counties sponsered by Chinese government and the proportion of 1:0.5:0.5 for N:P:K surposed by some developed countries. The results showed that the intensity of NPK fertilizer application currently presented a gradually increasing trend from south to north of Jiangsu, with the extremum ratio of 3.3, and the extremum ratios of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer were 3.3, 4.5 and 4.4, respectively. The average proportion of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer of 13 cities in Jiangsu was 1:0.39:0.26. Their proportion was relatively in equilibrium in southern Jiangsu, but the nutrient structure disorder was serious in northern Jiangsu. In Jiangsu, the environmental risk index of fertilization averaged at 0.69 and in the middle-range of environmental risk. The environmental risk index of fertilizer application in southern and central Jiangsu was respectively at the low and moderate levels, while that of cities in northern Jiangsu was at the moderate, serious or severe level. In Jiangsu, the regional difference of fertilizer application and environmental risk assessment were

  1. Fertility and Population Policy

    OpenAIRE

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

    2018-01-01

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

  2. Distinguishing Intensity Levels of Grassland Fertilization Using Vegetation Indices

    OpenAIRE

    Jens L. Hollberg; Jürgen Schellberg

    2017-01-01

    Monitoring the reaction of grassland canopies on fertilizer application is of major importance to enable a well-adjusted management supporting a sustainable production of the grass crop. Up to date, grassland managers estimate the nutrient status and growth dynamics of grasslands by costly and time-consuming field surveys, which only provide low temporal and spatial data density. Grassland mapping using remotely-sensed Vegetation Indices (VIs) has the potential to contribute to solving these ...

  3. Uranium in groundwater--Fertilizers versus geogenic sources.

    Science.gov (United States)

    Liesch, Tanja; Hinrichsen, Sören; Goldscheider, Nico

    2015-12-01

    Due to its radiological and toxicological properties even at low concentration levels, uranium is increasingly recognized as relevant contaminant in drinking water from aquifers. Uranium originates from different sources, including natural or geogenic, mining and industrial activities, and fertilizers in agriculture. The goal of this study was to obtain insights into the origin of uranium in groundwater while differentiating between geogenic sources and fertilizers. A literature review concerning the sources and geochemical processes affecting the occurrence and distribution of uranium in the lithosphere, pedosphere and hydrosphere provided the background for the evaluation of data on uranium in groundwater at regional scale. The state of Baden-Württemberg, Germany, was selected for this study, because of its hydrogeological and land-use diversity, and for reasons of data availability. Uranium and other parameters from N=1935 groundwater monitoring sites were analyzed statistically and geospatially. Results show that (i) 1.6% of all water samples exceed the German legal limit for drinking water (10 μg/L); (ii) The range and spatial distribution of uranium and occasional peak values seem to be related to geogenic sources; (iii) There is a clear relation between agricultural land-use and low-level uranium concentrations, indicating that fertilizers generate a measurable but low background of uranium in groundwater. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Semen collection and fertility in naturally fertile sandhill cranes

    Science.gov (United States)

    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 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).

  5. Fertilizers in cereals crops. Effect of fertilization in grain quality

    International Nuclear Information System (INIS)

    Melaj, Mariana

    1997-01-01

    In the last years the yields of the maize cultivation in the Pampeana production region have constantly increased, foreseeing higher increases of yield in the next years. Such increase is due, between other motives, to the use of hybrids of higher potential yield. There is a direct relation between the yield potential of a genotype and the nutrients demand, fact that constitutes one of the geneticists concerns. Maize hybrids reach its maximum expression when the plant is cultivated in good supplied soils with balanced quantities of nutrients that in several cases are reached with the practice of fertilization. The quantitative and qualitative vegetal response to the use of phosphate fertilizers depend of soils, of the environmental conditions, of fertilizer and the way of its application as well as of the maize hybrid that was used. To direct the practice of fertilization towards the reposition of the soil nutrients extracted by genotypes of high yield without producing excesses that increase costs and put in danger the environment, it is necessary to know the real coefficient used by the plants of the phosphorus available in the soils. The isotopic methodology allows to distinguish the phosphorus coming from two nutrient sources: soil and fertilizer, even in the juvenile phase of vegetal development and to evaluate the efficiency of fertilizers in plant nutrition. The objective of the present work was to evaluate the use of phosphorus coming from one of the phosphorus source available (soil, fertilizer), that should allow to increase and make more specific the knowledge's level of the different maize hybrids. This is obtained by determination of the grade of use of nutrient (of the soil) and of the nutrient of fertilizers, evaluating the qualitative and quantitative responses to fertilization

  6. Comparison of unenriched versus 15N-enriched fertilizer as a tracer for N fertilizer uptake

    International Nuclear Information System (INIS)

    Meints, V.W.; Shearer, G.; Kohl, D.H.; Kurtz, L.T.

    1975-01-01

    A greenhouse experiment was conducted on three soils with differing cropping and fertilization histories to determine whether unenriched fertilizer N can be used in the same manner as 15 N-enriched fertilizer to estimate the amount of plant N derived from fertilizer. Estimates using unenriched fertilizer N were compared with estimates using two 15 N enrichment levels. Use of unenriched fertilizer N led to underestimation of the amount of fertilizer N in the plant material in four of six cases when compared to 15 N-enriched fertilizer. Standard deviations of the estimates of fertilizer-derived N in plant material were considerably greater when unenriched fertilizer was used. (U.S.)

  7. [Fertility transition in Peru].

    Science.gov (United States)

    Ferrando, D; Aramburu, C E

    1992-12-01

    Data from national censuses and sample surveys are the basis for this examintion of differential fertility and the fertility transition in Peru. Changes in the level and structure of fertility in the 3 major geographic regions are compared, and the role of contraceptive usage and nuptiality changes in the fertility decline are analyzed. Peru's total fertility rate was estimated at 6.85 in 1965 and has since declined to 6.56 in 1965-70, 6.00 in 1970-75, 5.30 in 1975-80, 4.65 in 1980-85, and 4.00 in 1985-90. The fertility decline varied in intensity and timing in the geographic regions. A clear fertility decline began among upper and middle income groups in the principal cities in the 1960s, spreading gradually to the urban low income sectors. Not until the late 1970s did the fertility decline spread to the rest of the population, coinciding with the years of severe economic crisis. The urban total fertility rate declined from 6 to 3.77 during 1961-86, but rural fertility increased through 1972 to 8.12, before declining slightly to 7.62 in 1981 and more markedly to 6.65 in 1986. Sociocultural and economic differences between Peru's natural regions are appreciable, and account for the contrasts in fertility trends. The greatest changes occurred in metropolitan Lima, which already had relatively low fertility in 1961. Its total fertility rate declined 44% from 5.6 in 1961 to 3.13 in 1986. Fertility declined by slightly under 40% in the rest of the coast, by almost 25% in the jungle, and by scarcely 14% in the sierra. The total fertility rates in 1961 and 1986, respectively, were 6.38 and 4.13 on the coast, 6.64 and 6.45 in the highlands, and 7.92 and 5.97 in the lowlands. The fertility decline, especially in the lower classes, was a response initially to the process of cultural modernization which in slightly over 2 decades saw a profound transformation of Peru from a rural, Andean, illiterate, and agrarian society to an urban, coastal, literate, and commercial society

  8. [Multiple time scales analysis of spatial differentiation characteristics of non-point source nitrogen loss within watershed].

    Science.gov (United States)

    Liu, Mei-bing; Chen, Xing-wei; Chen, Ying

    2015-07-01

    Identification of the critical source areas of non-point source pollution is an important means to control the non-point source pollution within the watershed. In order to further reveal the impact of multiple time scales on the spatial differentiation characteristics of non-point source nitrogen loss, a SWAT model of Shanmei Reservoir watershed was developed. Based on the simulation of total nitrogen (TN) loss intensity of all 38 subbasins, spatial distribution characteristics of nitrogen loss and critical source areas were analyzed at three time scales of yearly average, monthly average and rainstorms flood process, respectively. Furthermore, multiple linear correlation analysis was conducted to analyze the contribution of natural environment and anthropogenic disturbance on nitrogen loss. The results showed that there were significant spatial differences of TN loss in Shanmei Reservoir watershed at different time scales, and the spatial differentiation degree of nitrogen loss was in the order of monthly average > yearly average > rainstorms flood process. TN loss load mainly came from upland Taoxi subbasin, which was identified as the critical source area. At different time scales, land use types (such as farmland and forest) were always the dominant factor affecting the spatial distribution of nitrogen loss, while the effect of precipitation and runoff on the nitrogen loss was only taken in no fertilization month and several processes of storm flood at no fertilization date. This was mainly due to the significant spatial variation of land use and fertilization, as well as the low spatial variability of precipitation and runoff.

  9. The Consequences of Parental Divorce on the Life Course Outcomes of Canadian Children

    Directory of Open Access Journals (Sweden)

    Valerie Martin

    2005-12-01

    Full Text Available Applying the theory of the intergenerational transmission of divorce, this paper examines the consequences of parental divorce on three aspects of the life course of children: union formation, nonmarital fertility, and marital dissolution. The 1995 Canadian General Social Survey (GSS is used to estimate various regression models (Cox proportional hazards. Results show that children of divorced parents have a significantly higher likelihood to have births outside of marriage, enter into cohabiting unions, and to experience higher levels of divorce. Throughout the paper, attention is placed on the markedly different behaviour observed in Quebec compared to elsewhere in Canada.

  10. Atmospheric nitrogen deposition in the Yangtze River basin: Spatial pattern and source attribution

    International Nuclear Information System (INIS)

    Xu, Wen; Zhao, Yuanhong; Liu, Xuejun; Dore, Anthony J.; Zhang, Lin; Liu, Lei; Cheng, Miaomiao

    2018-01-01

    The Yangtze River basin is one of the world's hotspots for nitrogen (N) deposition and likely plays an important role in China's riverine N output. Here we constructed a basin-scale total dissolved inorganic N (DIN) deposition (bulk plus dry) pattern based on published data at 100 observational sites between 2000 and 2014, and assessed the relative contributions of different reactive N (N r ) emission sectors to total DIN deposition using the GEOS-Chem model. Our results show a significant spatial variation in total DIN deposition across the Yangtze River basin (33.2 kg N ha −1 yr −1 on average), with the highest fluxes occurring mainly in the central basin (e.g., Sichuan, Hubei and Hunan provinces, and Chongqing municipality). This indicates that controlling N deposition should build on mitigation strategies according to local conditions, namely, implementation of stricter control of N r emissions in N deposition hotspots but moderate control in the areas with low N deposition levels. Total DIN deposition in approximately 82% of the basin area exceeded the critical load of N deposition for semi-natural ecosystems along the basin. On the basin scale, the dominant source of DIN deposition is fertilizer use (40%) relative to livestock (11%), industry (13%), power plant (9%), transportation (9%), and others (18%, which is the sum of contributions from human waste, residential activities, soil, lighting and biomass burning), suggesting that reducing NH 3 emissions from improper fertilizer (including chemical and organic fertilizer) application should be a priority in curbing N deposition. This, together with distinct spatial variations in emission sector contributions to total DIN deposition also suggest that, in addition to fertilizer, major emission sectors in different regions of the basin should be considered when developing synergistic control measures. - Highlights: • Total DIN deposition fluxes showed a significant spatial variation in the

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

    Science.gov (United States)

    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

  12. Household Fertilizers Use and Soil Fertility Management Practices ...

    African Journals Online (AJOL)

    Household Fertilizers Use and Soil Fertility Management Practices in Vegetable Crops Production: The Case of Central Rift Valley of Ethiopia. ... rate, which could leads to pollution of the environment from over dose application and from runoff in to the water bodies and leaching in to the ground water with economic loss.

  13. Globalization and Contemporary Fertility Convergence.

    Science.gov (United States)

    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.

  14. Study on the placement of phosphorus fertilizer to improve fertilizer utilization by lowland rice

    International Nuclear Information System (INIS)

    Sisworo, W.H.; Riswantoro; Mardjo, M.

    1976-01-01

    An experiment for studying the placement of phosphorus fertilizer was carried out in the glass house by using 32 P-labelled superphosphate. The specific activity of the labelled fertilizer used was 0,25 mCi/g P 2 O 5 . Three placement methods were studied: (1) Hill placement: Fertilizer was burried at a distance of 5cm from the plants at the depth of 5 cm, (2) Surface placement: Fertilizer was spread on the surface, and (3) Soil mixed application: Fertilizer was mixed with the soil at the depth of 5 cm. Superphosphate was applied at the rates of 0, 30, 60, 90, and 120 kg P 25 /ha. Results obtained from the experiment showed that the dry matter production was significantly affected by the methods of placement of phosphorus fertilizer. Soil mixed placement gave the lowest yield of dry plant material. It differed significantly from the two other methods of placement. However, there was no significant difference between hill and surface placement. The placement of phosphorus fertilizer significantly affected the total uptake of phosphorus nutrient, uptake fertilizer phosphorus, and the percentage of fertilizer utilization. Surface placement gave the highest utilization of fertilizer when supplied at rates higher than 60 kg P 2 O 5 /ha. At low rate applications, hill placement was the best, but, at rates higher than 60 kg P 2 O 5 /ha the percentage of fertilizer utilization decreased. Soil mixed application was the least efficient fertilizer utilization. (author)

  15. Multivariate analysis and geostatistics of the fertility of a humic rhodic hapludox under coffee cultivation

    Directory of Open Access Journals (Sweden)

    Samuel de Assis Silva

    2012-04-01

    Full Text Available The spatial variability of soil and plant properties exerts great influence on the yeld of agricultural crops. This study analyzed the spatial variability of the fertility of a Humic Rhodic Hapludox with Arabic coffee, using principal component analysis, cluster analysis and geostatistics in combination. The experiment was carried out in an area under Coffea arabica L., variety Catucai 20/15 - 479. The soil was sampled at a depth 0.20 m, at 50 points of a sampling grid. The following chemical properties were determined: P, K+, Ca2+, Mg2+, Na+, S, Al3+, pH, H + Al, SB, t, T, V, m, OM, Na saturation index (SSI, remaining phosphorus (P-rem, and micronutrients (Zn, Fe, Mn, Cu and B. The data were analyzed with descriptive statistics, followed by principal component and cluster analyses. Geostatistics were used to check and quantify the degree of spatial dependence of properties, represented by principal components. The principal component analysis allowed a dimensional reduction of the problem, providing interpretable components, with little information loss. Despite the characteristic information loss of principal component analysis, the combination of this technique with geostatistical analysis was efficient for the quantification and determination of the structure of spatial dependence of soil fertility. In general, the availability of soil mineral nutrients was low and the levels of acidity and exchangeable Al were high.

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

    Science.gov (United States)

    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.

  17. A Robust Profitability Assessment Tool for Targeting Agricultural Investments in Developing Countries: Modeling Spatial Heterogeneity and Uncertainty

    Science.gov (United States)

    Quinn, J. D.; Zeng, Z.; Shoemaker, C. A.; Woodard, J.

    2014-12-01

    In sub-Saharan Africa, where the majority of the population earns their living from agriculture, government expenditures in many countries are being re-directed to the sector to increase productivity and decrease poverty. However, many of these investments are seeing low returns because they are poorly targeted. A geographic tool that accounts for spatial heterogeneity and temporal variability in the factors of production would allow governments and donors to optimize their investments by directing them to farmers for whom they are most profitable. One application for which this is particularly relevant is fertilizer recommendations. It is well-known that soil fertility in much of sub-Saharan Africa is declining due to insufficient nutrient inputs to replenish those lost through harvest. Since fertilizer application rates in sub-Saharan Africa are several times smaller than in other developing countries, it is often assumed that African farmers are under-applying fertilizer. However, this assumption ignores the risk farmers face in choosing whether or how much fertilizer to apply. Simply calculating the benefit/cost ratio of applying a given level of fertilizer in a particular year over a large, aggregated region (as is often done) overlooks the variability in yield response seen at different sites within the region, and at the same site from year to year. Using Ethiopia as an example, we are developing a 1 km resolution fertilizer distribution tool that provides pre-season fertilizer recommendations throughout the agricultural regions of the country, conditional on seasonal climate forecasts. By accounting for spatial heterogeneity in soil, climate, market and travel conditions, as well as uncertainty in climate and output prices at the time a farmer must purchase fertilizer, this stochastic optimization tool gives better recommendations to governments, fertilizer companies, and aid organizations looking to optimize the welfare benefits achieved by their

  18. Fertile ground? : soil fertility management and the African smallholder

    NARCIS (Netherlands)

    Misiko, M.

    2007-01-01

    Keywords: smallholder farmers, soil fertility, experimentation, "inconvenience", realist.The focus in this thesis is to form a view of how well soil fertility research performs within the ever shifting smallholder contexts. This study examined application of agro-ecological

  19. Fertility Clinic Success Rates

    Science.gov (United States)

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

  20. Chinese culture and fertility decline.

    Science.gov (United States)

    Wu, C; Jia, S

    1992-01-01

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

  1. Dynamic Responses in a Plant-Insect System to Fertilization by Cormorant Feces

    Directory of Open Access Journals (Sweden)

    Gundula Kolb

    2015-04-01

    Full Text Available Theoretical arguments suggest that increased plant productivity may not only increase consumer densities but also their fluctuations. While increased consumer densities are commonly observed in fertilization experiments, experiments are seldom performed at a spatial and temporal scale where effects on population fluctuations may be observed. In this study we used a natural gradient in soil fertility caused by cormorant nesting. Cormorants feed on fish but defecate on their nesting islands. On these islands we studied soil nutrient availability, plant nutrient content and the density of Galerucella beetles, main herbivores feeding on Lythrum salicaria. In a common garden experiment, we followed larval development on fertilized plants and estimated larval stoichiometry. Soil nutrient availability varied among islands, and several cormorant islands had very high N and P soil content. Plant nutrient content, however, did not vary among islands, and there was no correlation between soil and plant nutrient contents. Beetle densities increased with plant nutrient content in the field study. However, there was either no effect on temporal fluctuations in beetle density or that temporal fluctuations decreased (at high P. In the common garden experiment, we found limited responses in either larval survival or pupal weights to fertilization. A possible mechanism for the limited effect of fertilization on density fluctuations may be that the distribution of L. salicaria on nesting islands was restricted to sites with a lower N and P content, presumably because high N loads are toxic.

  2. Environmental protection foliar fertilization in areas subject to limitation of fertilizers use

    International Nuclear Information System (INIS)

    Gavriluta, I.; Alexandrescu, A; Budoi, G.; Bireescu, L.; Bireescu, G.

    1999-01-01

    Significant increases of plant productivity have been recorded in field experiments conducted between 1991 - 1994 using general purpose complex foliar fertilizers as well as aminoacid containing complex foliar fertilizers. These increases at the same time had positive environmental effects against chemical pollution, especially with nitrates. As a rule, the greater the degree of nutrient efficiency, especially of nitrate, the lower are the losses, which are subject to transfer to the environment. So in the light of environmental protection against chemical pollution using foliar fertilization is certainly beneficial for crops and for all other components of the agricultural environment giving rise to its significant improvement. Both, foliar and soil fertilization in areas with limitation of fertilizer use should be carried out under a continuous and strict analytical check of plant, soil and water. Refs. 14 (author)

  3. The fertility decline in Kenya.

    Science.gov (United States)

    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

  4. Ovulation monitoring and fertility knowledge: Their relationship to fertility experience in a cross-sectional study.

    Science.gov (United States)

    Righarts, Antoinette; Dickson, Nigel P; Parkin, Lianne; Gillett, Wayne R

    2017-08-01

    Various aspects of fertility knowledge, including the timing of the fertile window, have consistently been found to be poor. Limited evidence also suggests ovulation monitoring to time intercourse could be common. However, there have been no studies that compare these two aspects of fertility and women's fertility/infertility experiences. To examine the frequency of ovulation monitoring and its relationship with fertility knowledge and experience. A cross-sectional study of women aged 25-50 years resident in southern New Zealand was undertaken in 2011. Randomly selected women were asked to complete a fertility questionnaire. Outcome prevalence measures were calculated with 95% confidence intervals (CI) and associations investigated using χ 2 tests and Poisson regression. Ovulation monitoring was common, having ever been undertaken by 31.4% (95% CI: 28.5-34.3%) of the 1034 participants. However, knowledge was poor, particularly regarding the fertile window. More women who had ever monitored ovulation correctly identified the fertile window, although the proportion was still very low (18.4 vs 13.1% in those who had not, P = 0.027). Regression modelling showed ovulation monitoring was independently associated with seeking medical help to conceive, education and fertility experience, but not with knowledge. This study confirms ovulation monitoring was commonly undertaken. However, many women, including those who had monitored their ovulation, had poor fertility knowledge and failed to identify the fertile window. Poor fertility knowledge needs to be addressed, especially among women intending to conceive. © 2017 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  5. Fertilizer nitrogen leaching in relation to water regime and the fertilizer placement method

    International Nuclear Information System (INIS)

    Moustafa, A.T.A.; Khadr, M.S.

    1983-01-01

    A field experiment was conducted at the farm of Sids Experimental Station, Ministry of Agriculture, Middle Egypt, to evaluate the effect of the water regime and fertilizer placement method on the leaching of urea fertilizer under field conditions. Ordinary and heavy irrigations were the water regimes, while side-banding and surface broadcasting were the fertilizer placement methods. Wheat (Giza 158, local variety) was planted, and urea labelled with 15 N at the rate of 100 kg N/ha was added at planting. The data obtained showed that in general the leaching process of urea fertilizer, as evaluated from the amounts of fertilizer nitrogen residues, is not uniform even within replicates. This is despite the fact that the average total amount of fertilizer nitrogen residues in the soil profile to a depth of 125 cm is almost the same in the different treatments. Data also show that the bulk of fertilizer nitrogen residues is accumulated in the surface soil layers, especially at 0-25 cm. Only 10% of the fertilizer nitrogen is detected below 75 cm and up to 125 cm depth of the soil profile. It could be concluded that urea leaching (amount and depth) under these conditions is affected mainly by the soil characteristics, namely soil pores. This is in addition to some other factors that cause variable concentrations in the soil solution leaving the root zone. (author)

  6. Male Fertility Issues

    Science.gov (United States)

    Fertility issues are common in boys and men getting cancer treatment. Fertility preservation options include sperm banking, testicular shielding, testicular sperm extraction (TESE), and testicular tissue freezing. Support and clinical trials are listed.

  7. Uptake of fertilizer nitrogen and soil nitrogen by rice using 15N-labelled nitrogen fertilizer

    International Nuclear Information System (INIS)

    Reddy, K.R.; Patrick, W.H. Jr.

    1980-01-01

    Data from five field experiments using labelled nitrogen fertilizer were used to determine the relative effects of soil nitrogen and fertilizer nitrogen on rice yield. Yield of grain was closely correlated with total aboveground nitrogen uptake (soil + fertilizer), less closely correlated with soil nitrogen uptake and not significantly correlated with fertilizer nitrogen uptake. When yield increase rather than yield was correlated with fertilizer nitrogen uptake, the correlation coefficient was statistically significant. (orig.)

  8. Distinguishing Intensity Levels of Grassland Fertilization Using Vegetation Indices

    Directory of Open Access Journals (Sweden)

    Jens L. Hollberg

    2017-01-01

    Full Text Available Monitoring the reaction of grassland canopies on fertilizer application is of major importance to enable a well-adjusted management supporting a sustainable production of the grass crop. Up to date, grassland managers estimate the nutrient status and growth dynamics of grasslands by costly and time-consuming field surveys, which only provide low temporal and spatial data density. Grassland mapping using remotely-sensed Vegetation Indices (VIs has the potential to contribute to solving these problems. In this study, we explored the potential of VIs for distinguishing five differently-fertilized grassland communities. Therefore, we collected spectral signatures of these communities in a long-term fertilization experiment (since 1941 in Germany throughout the growing seasons 2012–2014. Fifteen VIs were calculated and their seasonal developments investigated. Welch tests revealed that the accuracy of VIs for distinguishing these grassland communities varies throughout the growing season. Thus, the selection of the most promising single VI for grassland mapping was dependent on the date of the spectra acquisition. A random forests classification using all calculated VIs reduced variations in classification accuracy within the growing season and provided a higher overall precision of classification. Thus, we recommend a careful selection of VIs for grassland mapping or the utilization of temporally-stable methods, i.e., including a set of VIs in the random forests algorithm.

  9. Fertilizer standards for controlling groundwater nitrate pollution from agriculture: El Salobral-Los Llanos case study, Spain

    Science.gov (United States)

    Peña-Haro, S.; Llopis-Albert, C.; Pulido-Velazquez, M.; Pulido-Velazquez, D.

    2010-10-01

    SummaryAlthough the legislation on groundwater quality targets pollutant concentration, the effects of measures on non-point source pollution control are often evaluated in terms of their emission reduction potential at the source, not on their capacity of reducing the pollutant concentration in groundwater. This paper applies a hydro-economic modelling framework to an aquifer, El Salobral-Los Llanos aquifer (Mancha Oriental, Spain), where nitrate concentrations higher than those allowed by the EU Water Framework Directive and Groundwater Directive are locally found due to the intense fertilizer use in irrigated crops. The approach allows defining the economically optimal allocation of spatially variable fertilizer standards in agricultural basins using a hydro-economic model that links the fertilizer application with groundwater nitrate concentration at different control sites while maximizing net economic benefits. The methodology incorporates results from agronomic simulations, groundwater flow and transport into a management framework that yields the fertilizer allocation that maximizes benefits in agriculture while meeting the environmental standards. The cost of applying fertilizer standards was estimated as the difference between the private net revenues from actual application and the scenarios generated considering the application of the standards. Furthermore, the cost of applying fertilizer standards was compared with the cost of taxing nitrogen fertilizers in order to reduce the fertilizer use to a level that the nitrate concentration in groundwater was below the limit. The results show the required reduction of fertilizer application in the different crop areas depending on its location with regards to the control sites, crop types and soil-plant conditions, groundwater flow and transport processes, time horizon for meeting the standards, and the cost of implementing such a policy (as forgone benefits). According to the results, a high fertilizer price

  10. Adaptation, Spatial Heterogeneity, and the Vulnerability of Agricultural Systems to Climate Change and CO2 Fertilization: An Integrated Assessment Approach

    International Nuclear Information System (INIS)

    Antle, J.M.; Capalbo, S.M.; Elliott, E.T.; Paustian, K.H.

    2004-01-01

    In this paper we develop economic measures of vulnerability to climate change with and without adaptation in agricultural production systems. We implement these measures using coupled, site-specific ecosystem and economic simulation models. This modeling approach has two key features needed to study the response of agricultural production systems to climate change: it represents adaptation as an endogenous, non-marginal economic response to climate change; and it provides the capability to represent the spatial variability in bio-physical and economic conditions that interact with adaptive responses. We apply this approach to the dryland grain production systems of the Northern Plains region of the United States. The results support the hypothesis that the most adverse impacts on net returns distributions tend to occur in the areas with the poorest resource endowments and when mitigating effects of CO2 fertilization and adaptation are absent. We find that relative and absolute measures of vulnerability depend on complex interactions between climate change, CO2 level, adaptation, and economic conditions such as relative output prices. The relationship between relative vulnerability and resource endowments varies with assumptions about climate change, adaptation, and economic conditions. Vulnerability measured with respect to an absolute threshold is inversely related to resource endowments in all cases investigated

  11. Conference considers low fertility.

    Science.gov (United States)

    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.

  12. The Rule of Organic Fertilizer on Fertilizer Efficiency and Requirement Rate for Vegetable Crop on Inceptisols Ciherang, Bogor

    Directory of Open Access Journals (Sweden)

    Ladiyani Retno Widowati

    2009-09-01

    Full Text Available Utilization of organic fertilizer is an alternative to increase soil health and supply a small amount of plant nutrient. Meanwhile agricultural soil in Indonesia commonly have low organic carbon content (<2% therefore application of organic fertilizer is recommended. Based on that, the aim of the research is to measure the effectiveness of organic fertilizer on caisim (Brassica chinensis L. growth, to measure the release of N-NO3- and N-NH4+, to determine the recommendation of organic fertilizer for caisim on Incentisols Ciherang, Bogor. The research had been conducted at Research and Soil Testing Laboratory and green house of Soil Research Institute, Laladon – Bogor on April to July 2008 using soil sample of Inceptisols Ciherang, Bogor. The treatments were: Control (no fertilizer, NPK, NPK + 500 kg organic fertilizer, ¾ NPK + 500 kg organic fertilizer, ½ NPK + 500 kg organic fertilizer, ¼ NPK + 500 kg organic fertilizer, organic fertilizer 500kg, organic fertilizer 1000 kg, NPK + 750 kg organic fertilizer, and NPK + 250 kg organic fertilizer. The five replications research had been conducted with Completely Randomized Design. The result indicated thats: (1 NPK fertilizer increased with addition of organic fertilizer approved by the evidence of increasing of plant high 2-10%, leaves number 1-2%, and crop production 16-36%. The relative agronomic effectiveness (RAE of treatment NPK+various rate of organic fertilizer were higher than NPK alone with value of 136-181%. (2 The release of NH4+-N and NO3--N from anorganic fertilizer (NPK treatment in four weeks incubation period showed balance proportion with N rate. Nitrogen released from organic fertilizer in the same incubation period are 5.39 mg NH4+-N kg-1 and 12.39 mg NO3- -N kg-1. (3 The best organic fertilizer rate based on fertilizer curve for Inceptisols Cicadas-Bogor having low C and N-organic is 560 kg organic fertilizer + NPK (300 kg Urea ha-1; 50 kg SP-36 ha-1; 50 kg KCl ha-1 produce

  13. Fertilization in northern forests

    DEFF Research Database (Denmark)

    Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten

    2014-01-01

    resources into food, health and industrial products and energy. Fertilization in Sweden and Finland is currently practiced by extensive fertilization regimens where nitrogen fertilizers are applied once, or up to three times, during a rotation period, mainly in mature forest. This type of fertilization...... gives, in most cases, a small and transient effect on the environment as well as a high rate of return to the forest owner with low-economic risk. The increase in biomass production, however, is relatively small and consequently the impact on the processing industry and the bioeconomy is limited. More...... in combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different...

  14. FERTILIZATION OF VINE BY A 5-AMINOLEVULINIC ACID-BASED FERTILIZER AND ITS PROFITABILITY

    Directory of Open Access Journals (Sweden)

    VLADIMR IMANSK

    2013-03-01

    Full Text Available In this work we investigated the effect of different doses of NPKS fertilizer added into the soil for nutrient contents in the soil, as well as the quantity and quality of grapes. During the vegetation of the vine, we tested the 5-aminolevulinic acid-based fertilizer (ALA. We summarize that higher doses of fertilizer added into soil caused higher amounts of available nutrients. During the vegetation of the vine an increase of ALA had a positive effect on the optimal balance of nutrients. Fertilization also increased the grape-vine yield, with the strongest effect (by 68% observed due to the application of ALA during the vegetation period of the vine. Added fertilizers had a statistically significant influence on decreased sugar concentration in the grape-vine however the addition of fertilizer into the soil, mainly the application of ALA during vegetation of the vine (by 57% had a positive effect on increase of the total content of sugar in the grape-vine, produced on 1 hectare. The year had a significant influence on the economical evaluation.

  15. Protect Your Fertility

    Science.gov (United States)

    ... 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 ...

  16. Organic Biochar Based Fertilization

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  18. Shifted hot spots and nutrient imbalance in global fertilizer use for agriculture production in the past half century

    Science.gov (United States)

    Tian, H.; Lu, C.

    2016-12-01

    In addition to enhance agricultural productivity, synthetic nitrogen (N) and phosphorous (P) fertilizer application in croplands dramatically altered global nutrient budget, water quality, greenhouse gas balance, and their feedbacks to the climate system. However, due to the lack of geospatial fertilizer input data, current Earth system/land surface modeling studies have to ignore or use over-simplified data (e.g., static, spatially uniform fertilizer use) to characterize agricultural N and P input over decadal or century-long period. In this study, we therefore develop a global time-series gridded data of annual synthetic N and P fertilizer use rate in croplands, matched with HYDE 3,2 historical land use maps, at a resolution of 0.5º latitude by longitude during 1900-2013. Our data indicate N and P fertilizer use rates increased by approximately 8 times and 3 times, respectively, since the year 1961, when IFA (International Fertilizer Industry Association) and FAO (Food and Agricultural Organization) survey of country-level fertilizer input were available. Considering cropland expansion, increase of total fertilizer consumption amount is even larger. Hotspots of agricultural N fertilizer use shifted from the U.S. and Western Europe in the 1960s to East Asia in the early 21st century. P fertilizer input show the similar pattern with additional hotspot in Brazil. We find a global increase of fertilizer N/P ratio by 0.8 g N/g P per decade (phuman impacts on agroecosystem functions in the long run. Our data can serve as one of critical input drivers for regional and global assessment on agricultural productivity, crop yield, agriculture-derived greenhouse gas balance, global nutrient budget, land-to-aquatic nutrient loss, and ecosystem feedback to the climate system.

  19. Effect of organic and inorganic fertilizer applied together on N and P absorption and soil fertility

    International Nuclear Information System (INIS)

    Wang Kuibo; Yu Meiyan; Shen Xiuzhen; Wang Tongyan; Chen Xueliu; Wang Zhifen

    1994-01-01

    15 N trace experiments show that organic and inorganic fertilizer applied together promotes organic N mineralization and absorption. Base fertilizer is mainly for nutrition organs and spring fertilizer for reproduction organs. Organic and inorganic fertilizer applied together obtained the highest production efficiency of total N. Total P amount in wheat plant is slightly higher than that of inorganic N applied only, but P distribution in nutrition organs was slightly lower than that of inorganic N applied only. Organic and inorganic fertilizer applied together, not only promoted the production but also increased fertility of soil, so it is an important measure for wheat to obtain high production continuously

  20. Ethnicity and fertility in Nigeria.

    Science.gov (United States)

    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.

  1. Fertilizer nitrogen recovery efficiencies in crop production systems of China with and without consideration of the residual effect of nitrogen

    International Nuclear Information System (INIS)

    Yan, Xiaoyuan; Ti, Chaopu; Zhu, Zhaoliang; Vitousek, Peter; Chen, Deli; Leip, Adrian; Cai, Zucong

    2014-01-01

    China is the world’s largest consumer of synthetic nitrogen (N), where very low rates of fertilizer N recovery in crops have been reported, raising discussion around whether fertilizer N use can be significantly reduced without yield penalties. However, using recovery rates as indicator ignores a possible residual effect of fertilizer N—a factor often unknown at large scales. Such residual effect might store N in the soil increasing N availability for subsequent crops. The objectives of the present study were therefore to quantify the residual effect of fertilizer N in China and to obtain more realistic rates of the accumulative fertilizer N recovery efficiency (RE) in crop production systems of China. Long-term spatially-extensive data on crop production, fertilizer N and other N inputs to croplands in China were used to analyze the relationship between crop N uptake and fertilizer N input (or total N input), and to estimate the amount of residual fertilizer N. Measurement results of cropland soil N content in two time periods were obtained to compare the change in the soil N pool. At the provincial scale, it was found that there is a linear relationship between crop N uptake and fertilizer N input or total N input. With the increase in fertilizer N input, annual direct fertilizer N RE decreased and was indeed low (below 30% in recent years), while its residual effect increased continuously, to the point that 40–68% of applied fertilizer was used for crop production sooner or later. The residual effect was evidenced by a buildup of soil N and a large difference between nitrogen use efficiencies of long-term and short-term experiments. (paper)

  2. Pretreatment fertility counseling and fertility preservation improve quality of life in reproductive age women with cancer.

    Science.gov (United States)

    Letourneau, Joseph M; Ebbel, Erin E; Katz, Patricia P; Katz, Audra; Ai, Wei Z; Chien, A Jo; Melisko, Michelle E; Cedars, Marcelle I; Rosen, Mitchell P

    2012-03-15

    The post-treatment quality of life (QOL) impacts of receiving precancer-treatment infertility counseling and of pursuing fertility preservation have not been described in large-scale studies of reproductive age women with cancer. In total, 1041 women who were diagnosed between ages 18 and 40 years responded to a retrospective survey and reported whether they received infertility counseling before cancer treatment and whether they took action to preserve fertility. Five cancer types were included: leukemia, Hodgkin disease, non-Hodgkin lymphoma, breast cancer, and gastrointestinal cancer. Validated QOL scales were used: the Decision Regret Score, the Satisfaction with Life Scale (SWLS), and the brief World Health Organization QOL questionnaire. Overall, 560 women (61%) who received treatment that potentially could affect fertility were counseled by the oncology team, 45 (5%) were counseled by fertility specialists, and 36 (4%) took action to preserve fertility. Pretreatment infertility counseling by a fertility specialist and an oncologist resulted in lower regret than counseling by an oncologist alone (8.4 vs 11.0; P fertility preservation (6.6 vs 11.0; P fertility specialist counseling (23.0 vs 19.8; P = .09) or preserving fertility (24.0 vs 19.0; P = .05). Receiving specialized counseling about reproductive loss and pursuing fertility preservation is associated with less regret and greater QOL for survivors, yet few patients are exposed to this potential benefit. Women of reproductive age should have expert counseling and should be given the opportunity to make active decisions about preserving fertility. Copyright © 2011 American Cancer Society.

  3. Socioeconomic status and fertility decline

    DEFF Research Database (Denmark)

    Dribe, Martin; Breschi, Marco; Gagnon, Alain

    2017-01-01

    America to analyse the relationship between socio-economic status and fertility during the fertility transition. Using comparable analytical models and class schemes for each population, we examined the changing socio-economic differences in marital fertility and related these to common theories...

  4. Soil Fertility Status on Organic Paddy Experiment

    Directory of Open Access Journals (Sweden)

    Mujiyo

    2015-07-01

    Full Text Available The study aims to determine fertility status of the soil after organic paddy experiments using kinds and doses of organic fertilizers. Experiment was conducted at greenhouse laboratory in Faculty of Agriculture Sebelas Maret University Surakarta. Experimental design used completely randomized design with 9 kinds of treatment was replicated 3 times. Experiments were the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations that are based on fulfilling nutrient requirements of 120 kg N ha-1. Result shows that the use of cow manure, Azolla fertilizers and Azolla inoculum had no effect on changes of soil fertility status. Soil fertility status was not significantly correlated with cow manure (0,16ns, Azolla fertilizer (0,26ns and Azolla inoculum (0,16ns. Average of final soil fertility status included fertile category, which was similar as the initial soil fertility status. Average of final soil properties of treatment but nevertheless was relatively higher than in no treatment, indicating the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations had greater impact to soil properties. Cow manure despite increased available K2O and dry grain, but it did not significantly increase the soil fertility status from fertile to very fertile. This was presumably due to the relatively short experiment period, only one planting season had not given significant effect to soil properties. Implication of this study is the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations although did not increase the soil fertility status but could maintain soil fertility status as the initial conditions before planting.

  5. Temporal Trends in Fertility Rates

    DEFF Research Database (Denmark)

    Jensen, Martin Blomberg; Priskorn, Lærke; Jensen, Tina Kold

    2015-01-01

    OBJECTIVE: Increasing age at first childbirth has been suggested to increase the risk for infertility. Our objective is to determine whether women above thirty years of age historically have been able to sustain fertility rates above replacement level. DESIGN: A descriptive nationwide Danish study...... to determine total and age specific fertility rates. RESULTS: Total fertility rate (TFR) decreased from 4.1 to 1.8 children per woman and age specific fertility also decreased from 1901 to 2014. Women aged 30-34, 35-39 or 40-44 years in the first decade of the 20th century had higher fertility rates than...... for 10% of TFR in 1901 compared with 4% in 2014 despite usage of assisted reproduction. CONCLUSION: This nationwide study shows that women above 30 years of age historically have been able to sustain fertility rates above replacement level. This implies that other factors besides age are strong...

  6. Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group.

    Science.gov (United States)

    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.

  7. Fertility drugs and ovarian cancer.

    Science.gov (United States)

    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.

  8. Spatial variability of soil potassium in sugarcane areas subjected to the application of vinasse

    Directory of Open Access Journals (Sweden)

    LAÉRCIO A. DE CARVALHO

    2014-12-01

    Full Text Available When deposited on land the vinasse can promote improvement in fertility, however, often fertilizer application occurs in areas considered homogeneous, without taking into account the variability of the soil. The objective of this study was to evaluate the effect of vinasse application on potassium content in two classes of soils cultivated with sugarcane, and characterize the spatial variability of soil using geostatistical techniques. In the 2010 and 2011 crop year, soil samples were collected from an experimental grid at 0-0.2 and 0.2-0.4 m depth in three soils cultivated with sugarcane, totaling 90 samplings in each grid, for the determination of pH, calcium (Ca, magnesium (Mg, potassium (K, phosphorus (P, aluminum (Al and potential acidity (H + Al. The data have been submitted to analysis of descriptive statistics and the K attribute was subjected to geostatistical analysis. The coefficient of variation indicated medium and high variability of K for the three soils. The results showed that the spatial dependence of K increased in depth to FRce and decreased to PHlv, indicating that the attribute could have followed the pattern of distribution of clay in depth. The investigation of the spatial variability of K on the surface and subsurface soils provided the definition of management zones with different levels of fertility, which can be organized into sub-areas for a more efficient management of the resources and the environment.

  9. Fertility differentials in rural Bangladesh.

    Science.gov (United States)

    Khan, H T; Islam, S M; Khan, H M; Bari, R

    1993-01-01

    "Data from two sources in rural Bangladesh have been used in this study to examine the differentials in fertility by selected socio-economic and demographic factors. Results [indicate] that age at first marriage, education of spouses and availability of electricity in the household...have [an] inverse relationship with fertility. Higher fertility is observed for Muslim women than for non-Muslims. It has been found that fertility is the lowest to those women whose husbands are service holders and the highest for agriculture." excerpt

  10. Effect of N fertilizer and foliar-applied Fe fertilizer at various ...

    African Journals Online (AJOL)

    DrSohrabi

    2012-05-17

    May 17, 2012 ... yield component and chemical composition of soybean. (Glycine ... fertilizer are the main source of meeting the nitrogen (N) ... influence grain yield and protein concentration (Haq and .... The data were analyzed using the Statistical Analysis System ... application and interaction of Fe and N fertilizers had no.

  11. Spatial and temporal distributions of toxicity in receiving waters around an oil effluent discharge site

    International Nuclear Information System (INIS)

    Krause, P.R.

    1994-01-01

    Distributions of pollutants from a point source discharge within the water column may vary in both time and space. In this study, they examined the spatial and temporal patterns of toxicity from an oil production effluent (produced water) discharge plume using sea urchin fertilization and development bioassays. Specifically, they tested the sensitivity and response patterns of sea urchin gametes and early life stages exposed to receiving waters sampled along a 1 km transact near an active produced water outfall. Fertilization success and development of larvae to the pluteus stage varied significantly with proximity to the outfall, with reduced fertilization and larval development found closer to the outfall. Although estimated toxicity in receiving water samples, based on fertilization success, was variable in time -- perhaps responding to variation in the quantity or make-up of produced water discharges -- the general spatial pattern of toxicity along the sampling transact remained relatively constant. Strong evidence that field toxicity was directly attributable to produced water effluents was provided by sampling the receiving waters while the produced water discharge was not operating. At such a time, no toxicity was found at any of the field sites. Receiving water toxicity data, along with toxicity data from the effluent itself, were used to prepare a ''map'' of effective effluent concentrations along the sampling transect

  12. Bio fertilizer Application in a Fertigation System

    International Nuclear Information System (INIS)

    Ahmad Nazrul Abd Wahid; Latiffah Noordin; Hoe, P.C.K.

    2011-01-01

    Bio fertilizers contain live beneficial microorganisms that provide nutrients and other benefits to crops. At present, bio fertilizers can be found in solid and liquid forms. Liquid bio fertilizer can be one of the alternatives to chemical fertilizers and pesticides. Liquid bio fertilizer is produced through culturing of microorganisms that are known to have specific capabilities in helping plant growth. However, application of bio fertilizers in the form of solution is more tedious than that of solid bio fertilizers, which can be applied directly to plants, whereas the liquid form requires several stages of preparation before it can be applied to crops. In Malaysian Nuclear Agency, a study on the distribution of liquid bio fertilizers to crops through the fertigation system has been conducted. In Malaysia, this study has not been conducted in depth, since the present fertigation system is associated to delivery of solubilised mineral fertilizers. This paper discusses the application of liquid bio fertilizers through a fertigation system. Discussions cover technical aspects of bio fertilizer preparation and its application via the said system. Tomato plant was used as test crop to determine the capability and efficiency of bio fertilizer application through the fertigation system. (author)

  13. Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system

    KAUST Repository

    Kim, Youngjin; Chekli, Laura; Shim, Wang-Geun; Phuntsho, Sherub; Li, Sheng; Ghaffour, NorEddine; Leiknes, TorOve; Shon, Ho Kyong

    2016-01-01

    In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further

  14. Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group

    Science.gov (United States)

    Rowe, Heather

    2016-01-01

    Background 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. Objective To identify public opinion about sexual and reproductive health in Australia. Methods 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. Results 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. Conclusions 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. PMID:26878865

  15. Impact of child mortality and fertility preferences on fertility status in ...

    African Journals Online (AJOL)

    Objectives: To determine the effects of child mortality and fertility preference on fertility status in rural Ethiopia. Design: Case-referent where the cases were women with number of children ever born alive was less than five and controls were women with number of children ever born alive greater or equal to five.

  16. Fertilization increases paddy soil organic carbon density*

    Science.gov (United States)

    Wang, Shao-xian; Liang, Xin-qiang; Luo, Qi-xiang; Fan, Fang; Chen, Ying-xu; Li, Zu-zhang; Sun, Huo-xi; Dai, Tian-fang; Wan, Jun-nan; Li, Xiao-jun

    2012-01-01

    Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon (SOC) sequestration. We sampled soils from a long-term (25 years) paddy experiment in subtropical China. The experiment included eight treatments: (1) check, (2) PK, (3) NP, (4) NK, (5) NPK, (6) 7F:3M (N, P, K inorganic fertilizers+30% organic N), (7) 5F:5M (N, P, K inorganic fertilizers+50% organic N), (8) 3F:7M (N, P, K inorganic fertilizers+70% organic N). Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment. The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha. The SOC densities of all fertilizer treatments were greater than that of the check. Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers. The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues. Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization. Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC. PMID:22467369

  17. Fertilization increases paddy soil organic carbon density.

    Science.gov (United States)

    Wang, Shao-xian; Liang, Xin-qiang; Luo, Qi-xiang; Fan, Fang; Chen, Ying-xu; Li, Zu-zhang; Sun, Huo-xi; Dai, Tian-fang; Wan, Jun-nan; Li, Xiao-jun

    2012-04-01

    Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon (SOC) sequestration. We sampled soils from a long-term (25 years) paddy experiment in subtropical China. The experiment included eight treatments: (1) check, (2) PK, (3) NP, (4) NK, (5) NPK, (6) 7F:3M (N, P, K inorganic fertilizers+30% organic N), (7) 5F:5M (N, P, K inorganic fertilizers+50% organic N), (8) 3F:7M (N, P, K inorganic fertilizers+70% organic N). Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment. The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha. The SOC densities of all fertilizer treatments were greater than that of the check. Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers. The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues. Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization. Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC.

  18. Quantifying nitrogen leaching response to fertilizer additions in China's cropland

    International Nuclear Information System (INIS)

    Gao, Shuoshuo; Xu, Peng; Zhou, Feng; Yang, Hui; Zheng, Chunmiao; Cao, Wei; Tao, Shu; Piao, Shilong; Zhao, Yue; Ji, Xiaoyan; Shang, Ziyin

    2016-01-01

    Agricultural soils account for more than 50% of nitrogen leaching (L_N) to groundwater in China. When excess levels of nitrogen accumulate in groundwater, it poses a risk of adverse health effects. Despite this recognition, estimation of L_N from cropland soils in a broad spatial scale is still quite uncertain in China. The uncertainty of L_N primarily stems from the shape of nitrogen leaching response to fertilizer additions (N_r_a_t_e) and the role of environmental conditions. On the basis of 453 site-years at 51 sites across China, we explored the nonlinearity and variability of the response of L_N to N_r_a_t_e and developed an empirical statistical model to determine how environmental factors regulate the rate of N leaching (LR). The result shows that L_N-N_r_a_t_e relationship is convex for most crop types, and varies by local hydro-climates and soil organic carbon. Variability of air temperature explains a half (∼52%) of the spatial variation of LR. The results of model calibration and validation indicate that incorporating this empirical knowledge into a predictive model could accurately capture the variation in leaching and produce a reasonable upscaling from site to country. The fertilizer-induced L_N in 2008 for China's cropland were 0.88 ± 0.23 TgN (1σ), significantly lower than the linear or uniform model, as assumed by Food and Agriculture Organization and MITERRA-EUROPE models. These results also imply that future policy to reduce N leaching from cropland needs to consider environmental variability rather than solely attempt to reduce N_r_a_t_e. - Highlights: • L_N-N_r_a_t_e relationship is convex and varies by local hydro-climates and SOC. • Variability of temperature explains a half of spatial variation of N leaching rate. • L_N in 2008 were 0.88 ± 0.23 Tg, lower than the linear or uniform models. • Reducing L_N should consider background rather than decreasing N_r_a_t_e solely. - Variability of air temperature explains a half of

  19. Cancer and fertility preservation

    DEFF Research Database (Denmark)

    Lambertini, Matteo; Del Mastro, Lucia; Pescio, Maria C

    2016-01-01

    In the last years, thanks to the improvement in the prognosis of cancer patients, a growing attention has been given to the fertility issues. International guidelines on fertility preservation in cancer patients recommend that physicians discuss, as early as possible, with all patients...... of reproductive age their risk of infertility from the disease and/or treatment and their interest in having children after cancer, and help with informed fertility preservation decisions. As recommended by the American Society of Clinical Oncology and the European Society for Medical Oncology, sperm...... data have become available, and several issues in this field are still controversial and should be addressed by both patients and their treating physicians.In April 2015, physicians with expertise in the field of fertility preservation in cancer patients from several European countries were invited...

  20. [Fertility and health in Mexico].

    Science.gov (United States)

    Urbina-Fuentes, M; Echánove-Fernández, E

    1989-01-01

    Fertility, health, and family planning are not independent factors, but rather involve a series of biological and social mechanisms in close interaction with one another. The impact that a high fertility rate has on health is reflected mainly in a rise in the rates of maternal and child mortality. Similarly, fertility has a greater negative effect upon the health of groups characterized by high reproductive risk, high parity, short intergenesic intervals, and unwanted pregnancies. On the other hand, family planning -and specifically the use of contraceptive methods-helps to achieve a lowering of the fertility rate and also has a positive effect on maternal-child health. This situation can be observed in the case of Mexico, where fertility rates and tendencies, as well as maternal and child mortality, have been reduced during the past decade.

  1. The effect of N fertilization on sugar beet production, root activity, and the efficent use of fertilizer N

    International Nuclear Information System (INIS)

    Charanek, Ahmad

    1990-10-01

    This study includes 2 field experiments using 15 N labelled fertilizer on sugarbeets. Five fertilization treatments with 6 replicates in Autumn and 3 with 5 replicates in Spring were carried out for three years (1985-1987), in the fields of the Faculty of Agriculture, University of Damascus. The aim of the Autumn sugarbeet experiment was to study the effects of nitrogen fertilizer on the production of sugarbeet, root activity and the efficeint use of N from the fertilizer. The purpose of the Spring sugarbeet experiment was to compare two methods of N-fertilizer applications (surface and banding) and their effects on the utilization of N-fertilizer. Nitrogen fertilizer was applied as ammonium sulphate (21%) in Autumn at rates of 60, 120, 180 and 240 KgN/ha and as urea (46%) at 120 KgN/ha in Spring. The fertilizer was applied in two equal amounts, the first at the emergence and the second at the beginning of the optimal leaves development. Treatment at 120 Kg was only given labelled 15 N fertilizer. The purpose of this research study was to find out the optimal amount of fertilizer that produces the highest yield and the best nitrogen utilization rate. It was concluded from these results that the optimal amount of fertilizer needed to achieve the highest sugar content was between 120-180 KgN/ha. The second application of fertilizer affected positivily root production. The utilization rate of nitrogen in banding was more efficient than surface method at harvest of the second application. (author). 14 refs., 14 figs., 43 tabs

  2. Fertility behaviour of recent immigrants to Israel

    Directory of Open Access Journals (Sweden)

    2004-03-01

    Full Text Available The fertility practices of immigrants are a particularly interesting field of study for demographers, providing an insight into the fertility behaviour of individuals when both the society and the individual undergo a period of rapid change. This paper describes and compares the fertility behaviour of two large groups of immigrants, from the former Soviet Union (FSU and from Ethiopia to Israel in the last 20 years. The changes in fertility behaviour undergone in the same society and at the same time by two very different groups are examined. The findings reveal that the fertility behaviour of immigrants is indeed changing. The fertility of FSU immigrants is increasing and that of the Ethiopian immigrants decreasing, with accompanying changes in the proximate determinants of fertility. Although the fertility of immigrants is becoming more similar to that of the receiving society, the methods employed to achieve the fertility change are not necessarily similar, and, in some cases, diverge from the norms of the receiving society.

  3. Prediction of bull fertility.

    Science.gov (United States)

    Utt, Matthew D

    2016-06-01

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

  4. Radioactivity in Chemical Fertilizers

    International Nuclear Information System (INIS)

    Jankovic, M.; Nikolic, J.; Pantelic, G.; Rajacic, M.; Sarap, N.; Todorovic, D.

    2013-01-01

    The fertilizers are essential in agriculture as they supply nutrients to the farming fields. One of the sources of radioactivity other than those of natural origin is mainly due to extensive use of fertilizers. The concentrations of natural radionuclides, 40K, 226Ra, 238U and 235U in different chemical fertilizers, which are part of the regular control of imported goods from the border crossing were analyzed using gamma spectrometry with a high purity germanium (HPGe) detector, relative efficiency 20 %, in order to assess the implications of the extended use of chemical fertilizers. Measurements were performed at Vinca Institute, Radiation and Environmental Protection Department. The obtained results show remarkable wide variations in the radioactivity contents of different samples. The mean (ranges) of specific activities for gamma activity of those fertilizer samples for 40K, 226Ra, 238U and 235U are 4857 (23 - 12 324) Bq/kg, 87 (4-393) Bq/kg, 220 (26-1145) Bq/kg and 15 (1.6-53) Bq/kg, respectively. The radium equivalent activity (Ra eq ) as well as the external absorbed gamma dose rate (D) for all samples was also calculated.(author)

  5. Global nitrogen and phosphorus fertilizer use for agriculture production in the past half century: shifted hot spots and nutrient imbalance

    Science.gov (United States)

    Lu, Chaoqun; Tian, Hanqin

    2017-03-01

    In addition to enhancing agricultural productivity, synthetic nitrogen (N) and phosphorous (P) fertilizer application in croplands dramatically alters global nutrient budget, water quality, greenhouse gas balance, and their feedback to the climate system. However, due to the lack of geospatial fertilizer input data, current Earth system and land surface modeling studies have to ignore or use oversimplified data (e.g., static, spatially uniform fertilizer use) to characterize agricultural N and P input over decadal or century-long periods. In this study, we therefore develop global time series gridded data of annual synthetic N and P fertilizer use rate in agricultural lands, matched with HYDE 3.2 historical land use maps, at a resolution of 0.5° × 0.5° latitude-longitude during 1961-2013. Our data indicate N and P fertilizer use rates on per unit cropland area increased by approximately 8 times and 3 times, respectively, since the year 1961 when IFA (International Fertilizer Industry Association) and FAO (Food and Agricultural Organization) surveys of country-level fertilizer input became available. Considering cropland expansion, the increase in total fertilizer consumption is even larger. Hotspots of agricultural N fertilizer application shifted from the US and western Europe in the 1960s to eastern Asia in the early 21st century. P fertilizer input shows a similar pattern with an additional current hotspot in Brazil. We found a global increase in fertilizer N / P ratio by 0.8 g N g-1 P per decade (p human impacts on agroecosystem functions in the long run. Our data can serve as one of critical input drivers for regional and global models to assess the impacts of nutrient enrichment on climate system, water resources, food security, etc. Datasets available at doi:10.1594/PANGAEA.863323.

  6. Will sex selection reduce fertility?

    Science.gov (United States)

    Leung, S F

    1994-01-01

    Population control is one of the primary policies applied against poverty in many low income countries. The widespread prevalence of son preference in some countries such as China and India, however, works against any reduction of fertility. This is so because parents often continue to have children until they obtain the number of sons which they desire. The bias against girls has also led to higher abortion and mortality rates of female children. It is frequently argued that if sex selection methods are made available to parents so that they can control the gender of their children, population growth would be lowered and women's welfare improved. The author investigates both theoretically and numerically the impact of sex selection on fertility. A static quantity-quality model of fertility is used to compare fertility choices when parents cannot choose the gender of children versus a situation in which parents can choose gender. Empirical data are drawn from the 1976 Malaysian Family Life Survey. Analysis found that whether sex selection reduces fertility depends upon the second and third derivatives of the utility function and the child expenditure function. A numerical dynamic analysis is also presented. The simulation shows, using empirical dynamic models of fertility and the Monte Carlo integration technique, that sex selection on the firstborn child among the Chinese in Malaysia could reduce fertility by about 3%.

  7. Effect of addition of nitrate fertilizers on the efficient use of ammonium fertilizers uptake in salty soils

    International Nuclear Information System (INIS)

    Khalifa, Kh.; Zidan, A

    1993-01-01

    The effect of addition of nitrate fertilizers on the efficient use of ammonium fertilizers was studies using N 15 method, in pot experiment using salt affected alluvial soil, the objective of this study was to determine the ideal ratio of No 3 /NH 4 which enhance the efficiency of ammonium fertilizers. The results showed that the fresh and dry weights of maize (variety LG11) responded significantly to each type of fertilizer alone. Furthermore, the N-NO 3 fertilizer showed superiority over N-NH 4 Fertilizer. Wherever, the highest yield was obtained with a mixture of both (N-NO 3 and N-NH 4 ) with NO 3 /NH 4 ratio 1/8, in spite of the fact that the equivalent amounts of N were employed in all treatments. Under the given circumstances it has been recommended in salt affected soil in dry area, to use the above mentioned ratio for nitrogen fertilizer to obtain optimum yield. (author)

  8. Increasing Soil Organic Matter Enhances Inherent Soil Productivity while Offsetting Fertilization Effect under a Rice Cropping System

    Directory of Open Access Journals (Sweden)

    Ya-Nan Zhao

    2016-09-01

    Full Text Available Understanding the role of soil organic matter (SOM in soil quality and subsequent crop yield and input requirements is useful for agricultural sustainability. SOM is widely considered to affect a wide range of soil properties, however, great uncertainty still remains in identifying the relationships between SOM and crop yield due to the difficulty in separating the effect of SOM from other yield-limiting factors. Based on 543 on-farm experiments, where paired treatments with and without NPK fertilizer were conducted during 2005–2009, we quantified the inherent soil productivity, fertilization effect, and their contribution to rice yield and further evaluated their relationships with SOM contents under a rice cropping system in the Sichuan Basin of China. The inherent soil productivity assessed by rice grain yield under no fertilization (Y-CK was 5.8 t/ha, on average, and contributed 70% to the 8.3 t/ha of rice yield under NPK fertilization (Y-NPK while the other 30% was from the fertilization effect (FE. No significant correlation between SOM content and Y-NPK was observed, however, SOM content positively related to Y-CK and its contribution to Y-NPK but negatively to FE and its contribution to Y-NPK, indicating an increased soil contribution but a decreased fertilizer contribution to rice yield with increasing SOM. There were significantly positive relationships between SOM and soil available N, P, and K, indicating the potential contribution of SOM to inherent soil productivity by supplying nutrients from mineralization. As a result, approaches for SOM accumulation are practical to improve the inherent soil productivity and thereafter maintain a high crop productivity with less dependence on chemical fertilizers, while fertilization recommendations need to be adjusted with the temporal and spatial SOM variation.

  9. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Provider Pocket Guides Provider Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ... Patient Pocket Guides Patient Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ...

  10. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ...

  11. Fertility Preservation for Children Diagnosed with Cancer

    Science.gov (United States)

    ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  12. Farmers behavior on using fertilizer in West Java

    Science.gov (United States)

    Perdana, Tomy; Renaldy, Eddy; Utami, Hesty Nurul; Sadeli, Agriani Hermita; Mahra Arari, H.; Ginanjar, Tetep; Ajeng Sesy N., P.; Fernianda Rahayu, H.; Sanjaya, Sonny

    2018-02-01

    Fertilizer is one of the important materials in farming system to improve quality and quantity of harvest. Most of farmers in Indonesia using fertilizer, one of substantial fertilizer is NPK that contain of complex nutrient, there are nitrogen, phosphorus and potassium. There are tendency for farmers using NPK based on quality products and speed of decomposition. Nowadays, market size for NPK fertilizer has been dramatically increase and it will impact on intensify of fertilizer use. The potential requirement in marketing does not balanced with consumer behavior analysis. Meanwhile, agricultural sector (include horticulture, floriculture, bio-pharmacy and plantation) have been wieldly increase of the farming system annualy. This research is study case which is analyzed local NPK fertilizer competitive advantage compared to imported NPK fertilizer through consumer point of view towards product quality in four districts in West Java province, i.e., West Bandung, Garut, Bogor and Cianjur District with target respondents are farmers who use NPK fertilizer. NPK fertilizer qualities are based on product attributes, which are; availability, nutrient content, price, basic ingredients, form of fertilizer, speed of decomposition, label, color, type, design and size of packaging. It was analyzed using sematic differential attitude models and multi attribute attitude snake diagram model. The evaluation ranking of consumers interests towards fertilizer attribute characteristics showed that consumer intention before deciding to buy or use a NPK fertilizer will consider nutrient content, speed of decomposition, form of fertilizer and availability of products. Consumer's attitude towards all NPK fertilizer attribute quality illustrated that imported fertilizer is considered to be more positive than local fertilizer. Fertilizer companies or industries should be able to maintain their fertilizer production especially concerning nutrient content and availability of products through a

  13. Evaluating the influence of plant growth-promoting rhizobacteria as a bio-fertilizer under different fertility sources

    Science.gov (United States)

    Chemical fertilizers are being extensively used to satisfy the increasing demand for food. However, utilization of chemical fertilizers can be costly and over application for ensuring crop productivity may lead to environmental problems. As a result, interest in using bio-fertilizers to improve soil...

  14. Effects of partial fertilizer substitution by organic fertilizer on growth of peanut at seedling stage

    Science.gov (United States)

    Li, Yue; Li, Na; Luo, Peiyu; Wang, Yue; Dai, Jian; Yang, Jinfeng

    2017-12-01

    In response to the Ministry of agriculture’s action plan for chemical fertilizer reductions and organic fertilizers instead of fertilizersand discuss the optimum consumption and proportion of peanut biochar-based fertilization.Six different fertilization treatments were set up:C40, C50(standard consumption), C60, C40+M, C30+M and C20+M. Seelding height, chlorophyll content and total biomass were also measured on 6th, 2017. The results showed that C20+M treatment had the highest plant height and the highest biomass in Peanut Seedlings, while the content of chlorophyll increased with the amount of biochar applied.

  15. The Problem of Teenage Pregnancy: An Educational Imperative.

    Science.gov (United States)

    Suri, Kul Bhushan

    1994-01-01

    Examines data surrounding issues related to educational attitudes and attainment and teenage pregnancy, nonmarital births, and child poverty. Addresses proximate and root causes of rising U.S. rates of teenage pregnancy, correlations between nonmarital births and educational and occupational expectations, and educational and economic consequences.…

  16. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu Reprotopia_Main_Menu ... Cancer Fertility Preservation for Children Diagnosed with Cancer Patient Pocket Guides Patient Pocket Guides Patient Guides Fertility ...

  17. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open ... Diagnosed with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation ...

  18. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  19. Fertility and the economy.

    Science.gov (United States)

    Becker, G S

    1992-08-01

    Fertility and the economy is examined in the context of the Malthusian question about the links between family choices and longterm economic growth. Micro level differences are not included not are a comprehensive range of economic or determinant variables. Specific attention is paid to income and price effects, the quality of children, overlapping generations, mortality effects, uncertainty, and economic growth. Fertility and the demand for children in linked to parental incomes and the cost of rearing children, which is affected by public policies that change the costs. Demand is also related to child and adult mortality, and uncertainty about sex of the child. Fertility in one generation affects fertility in the next. Malthusian and neoclassical models do not capture the current model of modern economies with rising income/capita and human and physical capital, extensive involvement of married women in the labor force, and declining fertility to very low levels. In spite of the present advances in firm knowledge about the relationships between fertility and economic and social variables, there is still much greater ignorance of the interactions. The Malthusian utility function that says fertility rises and falls with income did hold up to 2 centuries of scrutiny, and the Malthusian inclusion of the shifting tastes in his analysis could be translated in the modern context to include price of children. The inclusion of net cost has significant consequences, i.e., rural fertility can be higher because the cost of rearing when children contribute work to maintaining the farm is lower than in the city. An income tax deduction for children in the US reduces cost. Economic growth raises the cost of children due the time spent on child care becoming more valuable. The modern context has changed from Malthusian time, and the cost of education, training, and medical care is relevant. The implication is that a rise in income could reduce the demand for children when

  20. Isotope studies on rice fertilization

    International Nuclear Information System (INIS)

    1978-01-01

    The aim of the report is to provide practical information on the efficient utilization of nitrogen fertilizers in rice production. Results obtained from field investigations during the years 1970 to 1974 in ten countries (Bangladesh, Burma, Indonesia, Republic of Korea, Sri Lanka, Taiwan, Thailand, Vietnam, India, Philippines), using 15 N-labelled nitrogen fertilizers (ammonium sulfate, urea) are given. The experiments, which were conducted both during the dry and wet seasons, included comparison of varieties, effect of placement, source and time of nitrogen fertilizer application on the yield and quality of rice. The data from the project is presented in table form. In most of the experiments, the addition of nitrogen increased the rice grain yield. The role of soil nitrogen vs. fertilizer nitrogen is compared, and it is concluded that the physiological growth stage at which fertilizer-derived nitrogen is absorbed is of great importance

  1. [Preliminary determination of organic pollutants in agricultural fertilizers].

    Science.gov (United States)

    Mo, Ce-hui; Li, Yun-hui; Cai, Quan-ying; Zeng, Qiao-yun; Wang, Bo-guang; Li, Hai-qin

    2005-05-01

    Organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) in agricultural fertilizers are new problem deserved more study. Eight kinds of organic pollutants including 43 compounds classified as US EPA priority pollutants in twenty one agricultural fertilizers which were universally used in China were determined by Gas chromatography-mass spectrum (GC-MS). Three kinds of organic pollutants including more than 5 compounds were detected in most fertilizers, composing mainly of phthalic acid esters (PAEs), nitrobenzenes (NBs) and polycyclic aromatic hydrocarbons (PAHs). There were 26 compounds detected in at least one fertilizer, five of them especially PAEs detected in most fertilizer and even in all fertilizers. Benzo(a)pyrene, a strongly carcinogenic compound was detected in two fertilizers. Higher concentrations of compounds were determined in those fertilizers such as multifunction compound fertilizers and coated fertilizers.

  2. GPR56 is essential for testis development and male fertility in mice.

    Science.gov (United States)

    Chen, Guangchun; Yang, Liquan; Begum, Shahinoor; Xu, Lei

    2010-12-01

    Testis development is critical for male fertility and continuation of the mammalian species. Essential structural components of testes are seminiferous tubules, which are lined by Sertoli cells and provide nutrients and physical protection for the maturation of sperm. Seminiferous tubule formation is initiated in embryos as testis cords and relies on their remodeling for maturation during development. Recently, three-dimensional image analyses showed that testis cords in different parts of embryonic gonads undergo distinct remodeling processes. How this asymmetric remodeling is regulated has not been investigated. We report here that the absence of an adhesion G protein-coupled receptor, GPR56, leads to partial disruption of seminiferous tubules and reduced fertility in male mice. The defects appear to originate asymmetrically in embryonic gonads, but subsequent to the initial establishment of testis cords, suggesting that GPR56 might act to establish a spatial and/or temporal cue for asymmetric cord remodeling during male gonad development. © 2010 Wiley-Liss, Inc.

  3. Queering the fertility clinic.

    Science.gov (United States)

    Mamo, Laura

    2013-06-01

    A sociologist examines contemporary engagements of queer bodies and identities with fertility biomedicine. Drawing on social science, media culture, and the author's own empirical research, three questions frame the analysis: 1. In what ways have queers on the gendered margins moved into the center and become implicated or central users of biomedicine's fertility offerings? 2. In what ways is Fertility Inc. transformed by its own incorporation of various gendered and queered bodies and identities? And 3. What are the biosocial and bioethical implications of expanded queer engagements and possibilities with Fertility Inc.? The author argues that "patient" activism through web 2.0 coupled with a largely unregulated free-market of assisted reproduction has included various queer identities as "parents-in-waiting." Such inclusions raise a set of ethical tensions regarding how to be accountable to the many people implicated in this supply and demand industry.

  4. Measuring P availability in soils fertilized with water-soluble P fertilizers using 32P methodologies

    International Nuclear Information System (INIS)

    McLaughlin, M.J.

    2002-01-01

    Isotope exchange kinetics was used in conjunction with standard procedures for assessing soil P status in soils fertilized with soluble phosphatic fertilizers. Soil samples were collected before fertilizer application in year 1 (one) from 23 of the 30 sites of the National Reactive Phosphate Rock project. Soil phosphorus test values were plotted against indices of pasture response to applied fertilizer, to assess the effectiveness of the various soil tests to predict site responsiveness to applied fertilizer. Isotopically exchangeable P was only weakly related to other measures of available P, with resin P having the best relationship with E values. In some samples, very large values for isotopically exchangeable P (E values) were determined in relation to P extractable by all reagents. Examination of the data however, revealed that all the samples with large E values in relation to extractable P had very low equilibrium concentrations of solution P and high buffering capacities. The best soil test, Bray 1, could account for only 50% of the variation in plant responsiveness to applied fertilizer, with Olsen and Resin tests slightly worse at 41% and the isotopic procedure at 39%. (author)

  5. High-fertility phenotypes: two outbred mouse models exhibit substantially different molecular and physiological strategies warranting improved fertility.

    Science.gov (United States)

    Langhammer, Martina; Michaelis, Marten; Hoeflich, Andreas; Sobczak, Alexander; Schoen, Jennifer; Weitzel, Joachim M

    2014-01-01

    Animal models are valuable tools in fertility research. Worldwide, there are more than 400 transgenic or knockout mouse models available showing a reproductive phenotype; almost all of them exhibit an infertile or at least subfertile phenotype. By contrast, animal models revealing an improved fertility phenotype are barely described. This article summarizes data on two outbred mouse models exhibiting a 'high-fertility' phenotype. These mouse lines were generated via selection over a time period of more than 40 years and 161 generations. During this selection period, the number of offspring per litter and the total birth weight of the entire litter nearly doubled. Concomitantly with the increased fertility phenotype, several endocrine parameters (e.g. serum testosterone concentrations in male animals), physiological parameters (e.g. body weight, accelerated puberty, and life expectancy), and behavioral parameters (e.g. behavior in an open field and endurance fitness on a treadmill) were altered. We demonstrate that the two independently bred high-fertility mouse lines warranted their improved fertility phenotype using different molecular and physiological strategies. The fertility lines display female- as well as male-specific characteristics. These genetically heterogeneous mouse models provide new insights into molecular and cellular mechanisms that enhance fertility. In view of decreasing fertility in men, these models will therefore be a precious information source for human reproductive medicine. Translated abstract A German translation of abstract is freely available at http://www.reproduction-online.org/content/147/4/427/suppl/DC1.

  6. Cattle manure fertilization increases fig yield

    OpenAIRE

    Leonel,Sarita; Tecchio,Marco Antonio

    2009-01-01

    Fertilization using organic compounds is complementary to chemical fertilization, being essential to integrated fruit production. Reports on fig tree (Ficus carica L.) organic fertilization and mineral nutrition are worldwide scarce, especially in Brazil. This experiment aimed to evaluate the effects of cattle manure fertilization on the yield and productivity of the fig tree 'Roxo de Valinhos' in Botucatu, São Paulo State, Brazil, during the 2002/03, 2003/04, 2004/05 and 2005/06 crop cycles....

  7. Does fertility decrease household consumption?

    OpenAIRE

    Jungho Kim; Henriette Engelhardt; Alexia Fürnkranz-Prskawetz; Arnstein Aassve

    2009-01-01

    This paper presents an empirical analysis of the relationship between fertility and a direct measure of poverty for Indonesia, a country, which has experienced unprecedented economic growth and sharp fertility declines over recent decades. It focuses on illustrating the sensitivity of the effect of fertility on household consumption with respect to the equivalence scale by applying the propensity score matching method. The analysis suggests that a newborn child decreases household consumption...

  8. Chinese women's participation in fertility discussions.

    Science.gov (United States)

    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

  9. Is fertility falling in Zimbabwe?

    Science.gov (United States)

    Udjo, E O

    1996-01-01

    With an unequalled contraceptive prevalence rate in sub-Saharan Africa, of 43% among currently married women in Zimbabwe, the Central Statistical Office (1989) observed that fertility has declined sharply in recent years. Using data from several surveys on Zimbabwe, especially the birth histories of the Zimbabwe Demographic and Health Survey, this study examines fertility trends in Zimbabwe. The results show that the fertility decline in Zimbabwe is modest and that the decline is concentrated among high order births. Multivariate analysis did not show a statistically significant effect of contraception on fertility, partly because a high proportion of Zimbabwean women in the reproductive age group never use contraception due to prevailing pronatalist attitudes in the country.

  10. Nutrition and fertility.

    Science.gov (United States)

    Pinelli, G; Tagliabue, A

    2007-12-01

    The first studies about fertility and nutrition date back to the 70ies and already showed a strict relation among female fertility, weight and body composition. However, the mechanisms of this connection started to be explained only after leptin's discovery. According to some authors' opinion, leptin could interact with reproductive axis at multiple sites with stimulatory effects at the hypothalamus and pituitary and stimulatory or inhibitory actions at the gonads. Leptin could play a role in other physiologic processes such as menstruation and pregnancy, and could initiate the complex process of puberty. It has been showed that conditions in which nutritional status is suboptimal, such as eating disorders, exercise induced amenhorrea, functional hypothalamic amenhorrea and polycystic ovarian syndrome, are associated with abnormal leptin levels. These conditions, are characterized by severe changes in body composition and dietary habits. Since leptin is regulated by body composition and dietary factors, (such as energy intake and macronutrient composition), a strict connection between nutritional intake and fertility regulated by leptin is confirmed. This review focuses on the current knowledge about nutritional factors that influence leptin levels. Since clinical and subclinical nutritional imbalance can determine the development and the maintenance of neuroendocrine and metabolic aberrations, studies on fertility need a deeper attention about dietary habits and nutritional status.

  11. Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system.

    Science.gov (United States)

    Kim, Youngjin; Chekli, Laura; Shim, Wang-Geun; Phuntsho, Sherub; Li, Sheng; Ghaffour, Noreddine; Leiknes, TorOve; Shon, Ho Kyong

    2016-06-01

    In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further for their FO performance tests and evaluated in terms of water flux and reverse salt flux. Using selected fertilizers, bio-methane potential experiments were conducted to examine the effect of fertilizers on anaerobic activity due to reverse diffusion. Mono-ammonium phosphate (MAP) showed the highest biogas production while other fertilizers exhibited an inhibition effect on anaerobic activity with solute accumulation. Salt accumulation in the bioreactor was also simulated using mass balance simulation models. Results showed that ammonium sulfate and MAP were the most appropriate for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution. Given toxicity of sulfate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system

    KAUST Repository

    Kim, Youngjin

    2016-02-09

    In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further for their FO performance tests and evaluated in terms of water flux and reverse salt flux. Using selected fertilizers, bio-methane potential experiments were conducted to examine the effect of fertilizers on anaerobic activity due to reverse diffusion. Mono-ammonium phosphate (MAP) showed the highest biogas production while other fertilizers exhibited an inhibition effect on anaerobic activity with solute accumulation. Salt accumulation in the bioreactor was also simulated using mass balance simulation models. Results showed that ammonium sulphate and MAP were the most appropriate for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution. Given toxicity of sulphate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR.

  13. Uranium and heavy metals in phosphate fertilizers

    International Nuclear Information System (INIS)

    Khater, A.E.M.

    2008-01-01

    Agricultural applications of chemical fertilizers are a worldwide practice. The specific activity of uranium-238 and heavy metals in phosphate fertilizers depends on the phosphate ore from which the fertilizer produced and on the chemical processing of the ore. Composite phosphate fertilizers samples where collected and the uranium-238 specific activity, in Bq/kg, and As, Cd, Cu, Pb, Se concentration, in ppm, were measured. The annual addition of these elements in soil due to fertilization were calculated and discussed. (author)(tk)

  14. Uranium and heavy metals in phosphate fertilizers

    International Nuclear Information System (INIS)

    Khater, Ashraf E.M.; King Saud University, Riyadh

    2008-01-01

    Full text: Agricultural applications of chemical fertilizers are a worldwide practice. The specific activity of uranium-238 and heavy metals in phosphate fertilizers depends on the phosphate ore from which the fertilizer produced and on the chemical processing of the ore. Composite phosphate fertilizers samples were collected and the uranium-238 specific activity, in Bq/kg, and As, Cd, Cu, Pb, Se concentration were measured. The annual addition of these elements in soil due to soil fertilization were calculated and discussed. (author)

  15. Fertility preservation during cancer treatment: clinical guidelines

    Science.gov (United States)

    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

  16. Fertility preservation: a challenge for IVF-clinics.

    Science.gov (United States)

    Dahhan, Taghride; Mol, Femke; Kenter, Gemma G; Balkenende, Eva M E; de Melker, Annemieke A; van der Veen, Fulco; Dancet, Eline A F; Goddijn, Mariëtte

    2015-11-01

    Acute fertility preservation for women is an interdisciplinary treatment that requires adequate information provision and early referral. This quality management project aimed to improve fertility preservation care by using a practical tool: Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis. Quality management project was executed between May 2011 and July 2013. This project has been executed in a university affiliated IVF-clinic in cooperation with two oncological sites and used a four-step strategy: (1) monitoring baseline referral process, (2) exploring baseline fertility preservation program by Strengths, Weaknesses, Opportunities and Threats' (SWOT)-analysis, (3) setting up a new fertility preservation program and (4) evaluating the new fertility preservation program by means of SWOT-analysis. During the three-months monitoring period, fertility preservation was requested for a total of 126 women. The mean age of the women was 33.8 years old (range 1-42 years old). Most requests came from women who wanted to cryopreserve oocytes because of age-related decline of fertility (n=90; 71%). Most requests for acute fertility preservation concerned women with breast cancer (n=16; 57%). Information leaflets and pre-consultation questionnaires for women improved the quality of first fertility preservation consultation as evaluated by final SWOT-analysis. Collaboration with oncological centres and information about fertility preservation improved the referral process. SWOT-analysis proved useful for setting up a new fertility preservation-program and can be recommended as a tool to improve the management and organisation of new types of reproductive care. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. The need to improve fertility awareness

    Directory of Open Access Journals (Sweden)

    Joyce Harper

    2017-06-01

    Full Text Available Women and men globally are delaying the birth of their first child. In the UK, the average age of first conception in women is 29 years. Women experience age-related fertility decline so it is important that men and women are well-informed about this, and other aspects of fertility. A group of UK stakeholders have established the Fertility Education Initiative to develop tools and information for children, adults, teachers, parents and healthcare professionals dedicated to improving knowledge of fertility and reproductive health.

  18. Fertility in female childhood cancer survivors

    DEFF Research Database (Denmark)

    De Bruin, Marie L; Van Dulmen-den Broeder, Eline; Van den Berg, Marleen H

    2009-01-01

    chemotherapy and radiotherapy may have an adverse effect on ovarian function, ovarian reserve and uterine function, clinically leading to sub-fertility, infertility, premature menopause and/or adverse pregnancy outcomes. Here we will first address normal female fertility and methods to detect decreased...... fertility. Hence we will focus on direct effects as well as late fertility-related adverse effects caused by chemotherapy and radiotherapy, and we will conclude with a summary of current options for fertility preservation in female childhood cancer survivors.......Advances in childhood cancer treatment over the past decades have significantly improved survival, resulting in a rapidly enlarging group of childhood cancer survivors. There is much concern, however, about the effects of treatment on reproductive potential. In women there is evidence that both...

  19. Are Nitrogen Fertilizers Deleterious to Soil Health?

    Directory of Open Access Journals (Sweden)

    Bijay- Singh

    2018-04-01

    Full Text Available Soil is one of the most important natural resources and medium for plant growth. Anthropogenic interventions such as tillage, irrigation, and fertilizer application can affect the health of the soil. Use of fertilizer nitrogen (N for crop production influences soil health primarily through changes in organic matter content, microbial life, and acidity in the soil. Soil organic matter (SOM constitutes the storehouse of soil N. Studies with 15N-labelled fertilizers show that in a cropping season, plants take more N from the soil than from the fertilizer. A large number of long-term field experiments prove that optimum fertilizer N application to crops neither resulted in loss of organic matter nor adversely affected microbial activity in the soil. Fertilizer N, when applied at or below the level at which maximum yields are achieved, resulted in the build-up of SOM and microbial biomass by promoting plant growth and increasing the amount of litter and root biomass added to soil. Only when fertilizer N was applied at rates more than the optimum, increased residual inorganic N accelerated the loss of SOM through its mineralization. Soil microbial life was also adversely affected at very high fertilizers rates. Optimum fertilizer use on agricultural crops reduces soil erosion but repeated application of high fertilizer N doses may lead to soil acidity, a negative soil health trait. Site-specific management strategies based on principles of synchronization of N demand by crops with N supply from all sources including soil and fertilizer could ensure high yields, along with maintenance of soil health. Balanced application of different nutrients and integrated nutrient management based on organic manures and mineral fertilizers also contributed to soil health maintenance and improvement. Thus, fertilizer N, when applied as per the need of the field crops in a balanced proportion with other nutrients and along with organic manures, if available with the

  20. Effect of Fertilization on Soil Fertility and Nutrient Use Efficiency at Potatoes

    Science.gov (United States)

    Neshev, Nesho; Manolov, Ivan

    2016-04-01

    The effect of fertilization on soil fertility, yields and nutrient use efficiency of potatoes grown under field experimental conditions was studied. The trail was conducted on shallow brown forest soil (Cambisols-coarse) during the vegetation periods of 2013 to 2015. The variants of the experiment were: control, N140; P80; K100; N140P80; N140K100; P80K100; N140P80K100; N140P80K100Mg33. The applied fertilization slightly decreased soil's pH after the harvest of potatoes compared to the soil pH their planting. Decreasing of pH was more severe at variant N (from 5,80 to 4,19 in 2014). The mineral nitrogen content in the soil after the harvest of potatoes was lower for the variants P, K and PK. The positive effect of fertilization on soil fertility after the end of the trails was more pronounced at variants NPK and NPKMg. The content of available nitrogen, phosphorus and potassium forms for these variants was the highest for each year. The highest content of mineral nitrogen was observed in 2013 (252,5 and 351,1 mg/1000g, respectively for variants NPK and NPKMg). It was due to extremely dry weather conditions during the vegetation in this year. Soil content of mineral N for the next two years was lower. The same tendency was observed for phosphorus and potassium was observed. In 2013 the P2O5 and K2O content in soil was the highest for the variants with full mineral fertilization - NPK (64,4 and 97,6 mg 100g-1 respectively for P2O5 and K2O) and NPKMg (65,2 and 88,0 mg 100g-1 respectively for P2O5 and K2O). The highest yields were recorded at variants NPK and NPKMg - 24,21 and 22,01 t ha-1, average for the studied period. The yield of variant NPK was 25 % higher than the yield from variant NP and 68 % higher than control. The partial factor productivity (PFPN, PFPP and PFPK) of the applied fertilizers was the highest at variant NPK. The PFPN (80,10 kg kg-1) for the yields of variant N was 57 % lower than the PFPN at variant NPK (180,36 kg kg-1). The PFPP and PFPK at

  1. Fertility preservation for medical reasons in girls and women: British fertility society policy and practice guideline.

    Science.gov (United States)

    Yasmin, Ephia; Balachandren, Neerujah; Davies, Melanie C; Jones, Georgina L; Lane, Sheila; Mathur, Raj; Webber, Lisa; Anderson, Richard A

    2018-04-01

    Fertility preservation in the female poses several challenges due to the invasive nature of the techniques available to achieve it. The guideline aims to bring together the evidence available for the measures for fertility preservation and their outcome. The guideline addresses fertility preservation for medical reasons and includes both oncological and non-oncological causes. The techniques that the guideline considers are: (i) embryo and oocyte cryopreservation; (ii) ovarian tissue cryopreservation; (iii) GnRH agonist suppression and (iv) ovarian transposition. Although ovarian tissue cryopreservation is still considered experimental, the availability of this technique is gaining momentum as more live births from auto-transplanted tissue are reported. The guideline also highlights use of current treatment modalities for benign and malignant conditions that have a better fertility sparing profile. The guideline recommends a multidisciplinary approach in counselling women and girls about the risk to their fertility and available techniques. The role of psychological support in assisting women and girls with decision-making is highlighted. The guideline also highlights the risks associated with these techniques. Women need to be medically fit to undergo invasive procedures. Fertility preservation techniques are appropriate when treatment has curative intent. Fertility preservation is a subject of on-going research on outcomes of different techniques and at the time of publication, studies are still likely to emerge adding to the available literature.

  2. [Effects of Chemical Fertilizers and Organic Fertilizer on Yield of Ligusticum chuanxiong Rhizome].

    Science.gov (United States)

    Liang, Qin; Chen, Xing-fu; Li, Yan; Zhang, Jun; Meng, Jie; Peng, Shi-ming

    2015-10-01

    To study the effects of different N, P, K and organic fertilizer (OF) on yield of Ligusticum chuanxiong rhizome, in order to provide the theoretical foundation for the establishment of standardization cultivation techniques. The field plot experiments used Ligusticum chuanxiong rhizome which planted in Pengshan as material, and were studied by the four factors and five levels with quadratic regression rotation-orthogonal combination design. According to the data obtained, a function model which could predict the fertilization and yield of Ligusticum chuanxiong rhizome accurately was established. The model analysis showed that the yields of Ligusticum chuanxiong rhizome were significantly influenced by the N, P, K and OF applications. Among these factors, the order of increase rates by the fertilizers was K > OF > N > P; The effect of interaction between N and K, N and OF, K and OF on the yield of Ligusticum chuanxiong rhizome were significantly different. High levels of N and P, N and organic fertilizer, K and organic fertilizer were conducive to improve the yield of Ligusticum chuanxiong rhizome. The results showed that the optimal fertilizer application rates of N was 148.20 - 172.28 kg/hm2, P was 511.92 - 599.40 kg/hm2, K was 249.70 - 282.37 kg/hm2, and OF was 940.00 - 1 104.00 kg/hm2. N, P, K and OF obviously affect the yield of Ligusticum chuanxiong rhizome. K and OF can significantly increase the yield of Ligusticum chuanxiong rhizome. Thus it is suggested that properly high mount of K and OF and appropriate increasing N are two favorable factors for cultivating Ligusticum chuanxiong.

  3. [Fertility in rural and urban areas of Mexico].

    Science.gov (United States)

    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

  4. Taxa-area Relationship (TAR) of Microbial Functional Genes with Long-TGerm Fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Yuting; Wu, Liyou; Clark, Ian; Xue, Kai; Van Nostrand, Joy D.; Deng, Ye; He, Zhili; Hirsch, Penny; Mcgrath, Steve; Zhou, Jizhong

    2010-05-17

    Diversity and spatial patterns in plant and animal communities are well documented as a positive-power law of a taxa-area relationship (TAR). At present little is known whether this also applies to soil microbial communities and whether long-term fertilization has an influence on the underlying microbial diversity. To test the effects of long-term fertilization on above-ground botanical diversity and below-ground microbial diversity, a nested sampling approach on Park Grass plots (12d& 11/2c) of Rothamsted Reseach in United Kingdom, both at ~;; pH 5 but with plant diversities of between 42 and 13 respectively were used. GeoChip 3.0, covering approximately 57, 000 gene sequences of 292 gene families involved in nitrogen, carbon, sulfur and phosphorus cycling, metal reduction and resistance, and organic contaminant degradation, was used to determine the gene area relationships for both functional and phylogenetic groups and the relationship to plant diversity. Our analysis indicated that the microbial communities were separated by different plant diversity based on DCA. The soil microbial diversity was in accord with plant diversity. Soil microbial community exhibited different z value with different plant diversity, z = 0.0449 with higher plant diversity and z = 0.0583 with lower plant diversity (P< 0.0001). These results suggest that the turnover in space of microorganisms may be higher with long-term fertilization.

  5. Fertility in Namibia. Changes in fertility levels in North-Central Namibia 1960-2001, including an assessment of the impact of HIV

    Directory of Open Access Journals (Sweden)

    Riikka Shemeikka

    2006-01-01

    Full Text Available The aim of this study was to estimate the development of fertility in North-Central Namibia, former Ovamboland, from 1960 to 2001. Special attention was given to the onset of fertility decline and to the impact of the HIV epidemic on fertility. An additional aim was to introduce parish registers as a source of data for fertility research in Africa.  Data used consisted of parish registers from Evangelical Lutheran congregations, the 1991 and 2001 Population and Housing Censuses, the 1992 and 2000 Namibia Demographic and Health Surveys, and the HIV sentinel surveillances of 1992-2004. Both period and cohort fertility were analysed. The P/F ratio method was used when analysing census data. The impact of HIV infection on fertility was estimated indirectly by comparing the fertility histories of women who died at an age of less than 50 years with the fertility of other women. The impact of the HIV epidemic on fertility was assessed both among infected women and in the general population.  Fertility in the study population began to decline in 1980. The decline was rapid during the 1980s, levelled off in the early 1990s at the end of war of independence and then continued to decline until the end of the study period. According to parish registers, total fertility was 6.4 in the 1960s and 6.5 in the 1970s, and declined to 5.1 in the 1980s and 4.2 in the 1990s. Adjustment of these total fertility rates to correspond to levels of fertility based on data from the 1991 and 2001 censuses resulted in total fertility declining from 7.6 in 1960-79 to 6.0 in 1980-89, and to 4.9 in 1990-99. The decline was associated with increased age at first marriage, declining marital fertility and increasing premarital fertility. Fertility among adolescents increased, whereas the fertility of women in all other age groups declined.  During the 1980s, the war of independence contributed to declining fertility through spousal separation and delayed marriages. Contraception

  6. Nutrient use efficiencies and crop responses to N, P and manure applications in Zimbabwean soils: Exploring management strategies across soil fertility gradients

    NARCIS (Netherlands)

    Tittonell, P.A.; Zingore, S.; Wijk, van M.T.; Corbeels, M.; Giller, K.E.

    2007-01-01

    The spatial variability in crop yields commonly observed in smallholder farms of sub-Saharan Africa is often caused by gradients of declining soil fertility with increasing distance from the homestead. This heterogeneity means that recommendations based on regional soil surveys are of limited value.

  7. On the fertility transition in Africa

    DEFF Research Database (Denmark)

    Mveyange, Anthony Francis

    A consensus among social scientists is that fertility rates in Africa are declining. What determines these declines? I present fresh evidence that shows education, especially for women, is an important determinant of the fertility transition in Africa. This finding is consistent with the predicti......A consensus among social scientists is that fertility rates in Africa are declining. What determines these declines? I present fresh evidence that shows education, especially for women, is an important determinant of the fertility transition in Africa. This finding is consistent...... with the predictions of the unified growth theory and sheds important insights in explaining the sustained income growth Africa has experienced since 1995. The paper also shows that the effects of income per capita and child mortality on fertility rates are non-robust and inconsistent with the predictions...

  8. Nanocomposites for controlled release of nitrogen fertilizer

    International Nuclear Information System (INIS)

    Silva, Viviane J.M. da; Visconte, Leila L.Y.; Nascimento, Regina Sandra V.

    2009-01-01

    The study aimed at the development of nano structured materials capable of reducing the rate of release of nitrogen in the soil from an agricultural nitrogen fertilizer. Four different systems of polymer composites were prepared: (1) montmorillonite clay/fertilizer, (2) montmorillonite clay/thermoplastic starch and fertilizer, (3) montmorillonite clay/fertilizer, thermoplastic starch and low-density polyethylene (LDPE) and also (4) montmorillonite clay/fertilizer, thermoplastic starch and polycaprolactone. It was confirmed the formation of nano structured materials by elemental analysis (CHN) and X-ray diffraction (XRD). The kinetics of nitrogen release was detected by enzymatic colorimetric analysis and spectroscopy in the ultraviolet/visible. The results showed that all materials evaluated were able to reduce the rate of release of nitrogen in the fertilizers. (author)

  9. Abortion Legalization and Life-Cycle Fertility

    Science.gov (United States)

    Ananat, Elizabeth Oltmans; Gruber, Jonathan; Levine, Phillip

    2007-01-01

    The early-1970s abortion legalization led to a significant drop in fertility. We investigate whether this decline represented a delay in births or a permanent reduction in fertility. We combine Census and Vital Statistics data to compare the lifetime fertility of women born in early-legalizing states, whose peak childbearing years occurred in the…

  10. Foods That Can Affect Fertility

    Science.gov (United States)

    ... That Can Affect Fertility Print Email Foods That Can Affect Fertility By Caroline Kaufman, MS, RDN Published ... the American Society for Reproductive Medicine. While couples can't control all of the causes of infertility, ...

  11. Use of organic fertilizer and bio fertilizer in a modern planting system to increase the productivity of vanilla plant

    International Nuclear Information System (INIS)

    Ahmad Nazrul Abd Wahid; Phua Choo Kwai Hoe; Shyful Azizi Abdul Rahman; Mohd Fajri Osman; Latiffah Noordin; Abdul Razak Ruslan; Maizatul Akmam Mhd Nasir; Hazlina Abdullah; Amirul Azmi Supuan; Misman Sumin; Ahamad Sahali Mardi; Khairuddin Abdul Rahim

    2010-01-01

    Vanilla is a plant belonging to the orchid family and native to Mexico. In Malaysia, research and cultivation of vanilla plants are becoming more popular and intensive because the plant has a high commercial value. Fertilizing of vanilla plants is important to enhance the nutrients needed by the plants for growth and vanilla pod production. In 1999, research in MARDI showed that the use of chemical fertilizer NPK (15:15:15) was suitable for vanilla plants. For plants that have not produced vanilla pods foliar fertilizer must be sprayed and foliar fertilizer application must be reduced at pod production stage. The fertilizer programme is almost similar to those of other vanilla producing countries such as Indonesia and Mexico. In Indonesia, studies on organic farming of vanilla have been conducted. They have produced chemical-free vanilla fertilizer products such as Bio-Fob, Bio-TRIBA and Organo TRIBA Compost. We in Malaysian Nuclear Agency conducted a study on the effects of organic and bio fertilizers on vanilla at the vanilla experimental plot. This plot adopts the modern system of vanilla planting. The study involved the use of organic and bio fertilizer products produced in Nuclear Malaysia such as Organik NF, plant growth promoter and phosphate solubiliser and imported commercial orchid mycorrhizal bio fertilizer from Korea. The application of these fertilizers is by placing the fertilizers on the planting media in poly bags with replications according to the treatments. Observations were made weekly for 15 weeks by measuring of parameters including the bud growth and leaf number. These data are plotted in graphical form for evaluation.(author)

  12. Desertification, Ecological and N, P, K, Mg fertilization changes on crop production in Hungary

    International Nuclear Information System (INIS)

    Laszio, M.

    2009-01-01

    Today, all soils and ecosystems in the World and Europe are facing similar threats in particular the impacts of global climate change the effects of land-use change. So, fragile arid and semi-arid areas are in urgent need to understand of integrated conservation and restoration approaches that can contribute significantly to prevent and reduce the widespread on going land and biodiversity degradation, desertification processes, such as erosion, flooding, overgrazing, drought, forest fire and salinization. this paper will establish promising integrated climate-soil-fertilization-crop system models taking into account the impact of combined drivers on soil processes, e. g. climate and fertilization changes in land use and management conservation based on a close participation of scientists with stake holder groups in the degradation and desertification hot sports, that can be transferred across a wide range of temporal and spatial scales. (Author) 8 refs.

  13. Sex and Fertility After SCI

    Science.gov (United States)

    ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  14. Societal foundations for explaining fertility: Gender equity

    Directory of Open Access Journals (Sweden)

    Peter McDonald

    2013-05-01

    Full Text Available BACKGROUND Gender equity theory in relation to fertility argues that very low fertility is the result of incoherence in the levels of gender equity in individually-oriented social institutions and family-oriented social institutions. The salience of gender to the fertility transition is strong in theory but not as strong in specification of testable hypotheses as has been pointed out in the literature. OBJECTIVE The paper aims to clarify the specification of gender equity theory through a discussion of the difference between equity and equality and to suggest methods that might be applied to test the theory. METHODS The theory is restated and further developed using literature from different disciplines. The method is described using a decomposition of fertility for women by human capital levels. RESULTS The clarification of the theory includes a reminder that the theory relates to differences in fertility between countries and not to differences in fertility between women in the same country. In comparisons between countries, higher gender equity leads to higher fertility. In comparisons of fertility across women in the same country, higher gender equity does not necessarily imply higher fertility. In relation to measurement, a specification is suggested that effectively compares women across countries controlling for their level of human capital. Simple graphics are used to indicate ways in which fertility between countries may vary. CONCLUSIONS The paper concludes that it is likely the gender equity theory can be tested more readily by examining the behaviour across countries of women with higher levels of human capital.

  15. Fertility preservation in young cancer patients

    Directory of Open Access Journals (Sweden)

    Ariel Revel

    2010-01-01

    Full Text Available As a result of advances in treatment, almost 80% of children and adolescents who receive a diagnosis of cancer become long-term survivors. The increased survival rate of children and adolescents with cancer has resulted in a major interest in the long-term effects of cancer treatment on the possibility for future fertility. Currently established methods for the preservation of fertility are available only for pubertal males and females. Pubertal male cancer patients should be encouraged to freeze numerous sperm samples even when sperm count and motility are poor. In these cases, intracytoplasmic sperm injection is a powerful technique compared with intrauterine insemination since thawed sperm samples with poor parameters can produce relatively high fertilization rates resulting in normal pregnancies and deliveries. Married pubertal women should be proposed ovulation induction, follicular aspiration, and fertilization with husband sperm. Single women could benefit from vitrification of oocytes. This requires a delay of about 3 weeks in the commencement of chemotherapy to enable follicular growth. Fertility preservation for prepubertal patients is more of a problem. Young girls could be offered cryopreservation of gametes in the gonadal tissue. Cryopreservation of testicular tissue was suggested for fertility preservation for young boys, but this method is totally experimental and not currently offered. Discussing future fertility is part of the consultation of young female and male patients facing potentially gonadotoxic cancer therapy. It is the role of reproductive specialists to create various options in their laboratory to preserve fertility potential of cancer patients.

  16. Fertilizing Douglas-fir forests.

    Science.gov (United States)

    Richard E. Miller; Roger D. Right

    1979-01-01

    This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses factors that affect costs and revenues from investments in forest...

  17. Olive and citrus tree crops and their fertilization in Greece: Field studies with 15N labelled fertilizers

    International Nuclear Information System (INIS)

    Papanicolaou, E.P.

    1982-01-01

    Fertilizer use for tree crops in Greece is increasing rapidly, however, fertilizer experiments with olive and citrus tree crops have given results which were often inconclusive. The value of using isotopically labelled fertilizers to directly measure fertilizer uptake is thus obvious. A preliminary experiment determined that relatively low enriched 15 N fertilizers (1.0-1.5% atom excess) could be accurately detected in citrus trees. The concentration of added N was higher in the leaves than in the wood and fruit. In a second study foliarly applied 15 N urea was found to be taken up more efficiently than broadcast urea or ammonium sulphate. In an initial sampling distribution of N among the plant parts was similar to that of the initial study, although a final harvest and analysis must still be conducted. (author)

  18. The Determinants of Low Fertility in India

    Science.gov (United States)

    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

  19. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... options further? Fertility Preservation - Where Does It Fit? Options for Fertility Preservation The following diagram gives a brief description of fertility preservation options available to children diagnosed with cancer before and ...

  20. Arbuscular mycorrhizal colonization in soil fertilized by organic and mineral fertilizers

    Science.gov (United States)

    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 arbuscular mycorrhizal colonization of roots.

  1. Agriculture: Nutrient Management and Fertilizer

    Science.gov (United States)

    Fertilizers and soil amendments can be derived from raw materials, composts and other organic matter, and wastes, such as sewage sludge and certain industrial wastes. Overuse of fertilizers can result in contamination of surface water and groundwater.

  2. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Resources Peer Counseling Blog About Media Donate close search Understanding Spinal Cord Injury What is a Spinal ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ...

  3. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ... health care products or services, or control the information found on external websites. The Hill Foundation is ...

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

    Science.gov (United States)

    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.

  5. Sex and Fertility After SCI

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    Full Text Available ... Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord ... a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. Rowles, MS, ...

  6. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  7. Male fertility in cystic fibrosis.

    LENUS (Irish Health Repository)

    Chotirmall, S H

    2011-04-05

    Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to Irish CF males. A Descriptive Study utilizing prospective coded questionnaires was mailed to a male CF cohort (n=50). Sections included demographics, fertility knowledge & investigation. Response rate was 16\\/50 (32%). All were aware that CF affected their fertility. More than two-thirds (n=11) were able to provide explanations whilst only one-third (n=5) provided the correct explanation. Significant numbers stated thoughts of marriage and a future family. Half have discussed fertility with a healthcare professional (HCP). Mean age of discussion was 21.9 years. One third preferred an earlier discussion. The commonest first source for information was written material which was also the preferred source. Three-quarters requested further information preferring again, written material. Significant gaps in sex education of Irish CF males exist. Discussion should be initiated by HCPs and centre-directed written material devised to address deficiencies.

  8. Three Cell Fusions during Double Fertilization.

    Science.gov (United States)

    Sprunck, Stefanie; Dresselhaus, Thomas

    2015-05-07

    Fertilization of both egg and central cell is a major distinguishing feature of flowering plants. Now, Maruyama et al. report a third cell fusion event between the persistent synergid and the fertilized central cell shortly after double fertilization in Arabidopsis. This causes rapid dilution of pollen tube attractant(s), preventing polytubey. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. The effects of ant nests on soil fertility and plant performance: a meta-analysis.

    Science.gov (United States)

    Farji-Brener, Alejandro G; Werenkraut, Victoria

    2017-07-01

    Ants are recognized as one of the major sources of soil disturbance world-wide. However, this view is largely based on isolated studies and qualitative reviews. Here, for the first time, we quantitatively determined whether ant nests affect soil fertility and plant performance, and identified the possible sources of variation of these effects. Using Bayesian mixed-models meta-analysis, we tested the hypotheses that ant effects on soil fertility and plant performance depend on the substrate sampled, ant feeding type, latitude, habitat and the plant response variable measured. Ant nests showed higher nutrient and cation content than adjacent non-nest soil samples, but similar pH. Nutrient content was higher in ant refuse materials than in nest soils. The fertilizer effect of ant nests was also higher in dry habitats than in grasslands or savannas. Cation content was higher in nests of plant-feeding ants than in nests of omnivorous species, and lower in nests from agro-ecosystems than in nests from any other habitat. Plants showed higher green/root biomass and fitness on ant nests soils than in adjacent, non-nest sites; but plant density and diversity were unaffected by the presence of ant nests. Root growth was particularly higher in refuse materials than in ant nest soils, in leaf-cutting ant nests and in deserts habitats. Our results confirm the major role of ant nests in influencing soil fertility and vegetation patterns and provide information about the factors that mediate these effects. First, ant nests improve soil fertility mainly through the accumulation of refuse materials. Thus, different refuse dump locations (external or in underground nest chambers) could benefit different vegetation life-forms. Second, ant nests could increase plant diversity at larger spatial scales only if the identity of favoured plants changes along environmental gradients (i.e. enhancing β-diversity). Third, ant species that feed on plants play a relevant role fertilizing soils

  10. The use of alternative fertilizers to increase soil fertility and yield of sunflower in North-Eastern Kazakhstan

    Directory of Open Access Journals (Sweden)

    Kulzhanova S.M.

    2018-01-01

    Full Text Available the article contains data from studies conducted in 2015–2016 in the North-Еastern part of Kazakhstan. In the experiments the effect of various doses of non-traditional fertilizer together with mineral fertilizer on the yield of sunflower was investigated. Various doses and ratios of mineral fertilizers have been applied, which can affect the yield of sunflower. As a source material, varieties of sunflower of Russian breeding Zarya and a hybrid of Fortimi USA breeding and non-traditional fertilizers – zeolite are taken. In order to determine the effect on the fertility of soils, the agrochemical characteristics of soils in land areas and the content of mobile forms of nutrients were studied. The main agrochemical characteristics and content of mobile forms of nutrients for soil of land plots are investigated in the article.

  11. Fertility preservation in young patients with cancer

    Directory of Open Access Journals (Sweden)

    Virender Suhag

    2015-01-01

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

  12. Does fertility decrease household consumption?: An analysis of poverty dynamics and fertility in Indonesia

    Directory of Open Access Journals (Sweden)

    Jungho Kim

    2009-06-01

    Full Text Available This paper presents an empirical analysis of the relationship between fertility and a direct measure of poverty for Indonesia, a country, which has experienced unprecedented economic growth and sharp fertility declines over recent decades. It focuses on illustrating the sensitivity of the effect of fertility on household consumption with respect to the equivalence scale by applying the propensity score matching method. The analysis suggests that a newborn child decreases household consumption per person by 20 percent within four years. When the estimates of equivalence scales implied by the Indonesian sample are applied, the effect of a child on household consumption is still negative, but the magnitudes are in the range from 20 to 65 percent of that found with the per-capita expenditure as a measure of consumption. Therefore, it is suggested that the analysis based on the conventional measure of poverty is likely to exaggerate the effect of fertility on poverty at least because of the neglect of the proper equivalence scale.

  13. What if fertility decline is not permanent? The need for an evolutionarily informed approach to understanding low fertility.

    Science.gov (United States)

    Burger, Oskar; DeLong, John P

    2016-04-19

    'Demographic transition theory' assumes that fertility decline is irreversible. This commonly held assumption is based on observations of recent and historical reductions in fertility that accompany modernization and declining mortality. The irreversibility assumption, however, is highly suspect from an evolutionary point of view, because demographic traits are at least partially influenced by genetics and are responsive to social and ecological conditions. Nonetheless, an inevitable shift from high mortality and fertility to low mortality and fertility is used as a guiding framework for projecting human population sizes into the future. This paper reviews some theoretical and empirical evidence suggesting that the assumption of irreversibility is ill-founded, at least without considerable development in theory that incorporates evolutionary and ecological processes. We offer general propositions for how fertility could increase in the future, including natural selection on high fertility variants, the difficulty of maintaining universal norms and preferences in a large, diverse and economically differentiated population, and the escalating resource demands of modernization. © 2016 The Author(s).

  14. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... this website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers ... Visit the Oncofertility Consortium Web site Use the online Clinic/Center Finder to find the fertility preservation ...

  15. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Online Fertility Preservation Toolkit for Patients and Their Providers Open menu Reprotopia_Main_Menu About SaveMyFertility Provider ... of a clinical study approved by an IRB . Resources For more information about infertility risk and fertility ...

  16. Atmospheric nitrogen deposition in the Yangtze River basin: Spatial pattern and source attribution.

    Science.gov (United States)

    Xu, Wen; Zhao, Yuanhong; Liu, Xuejun; Dore, Anthony J; Zhang, Lin; Liu, Lei; Cheng, Miaomiao

    2018-01-01

    The Yangtze River basin is one of the world's hotspots for nitrogen (N) deposition and likely plays an important role in China's riverine N output. Here we constructed a basin-scale total dissolved inorganic N (DIN) deposition (bulk plus dry) pattern based on published data at 100 observational sites between 2000 and 2014, and assessed the relative contributions of different reactive N (N r ) emission sectors to total DIN deposition using the GEOS-Chem model. Our results show a significant spatial variation in total DIN deposition across the Yangtze River basin (33.2 kg N ha -1 yr -1 on average), with the highest fluxes occurring mainly in the central basin (e.g., Sichuan, Hubei and Hunan provinces, and Chongqing municipality). This indicates that controlling N deposition should build on mitigation strategies according to local conditions, namely, implementation of stricter control of N r emissions in N deposition hotspots but moderate control in the areas with low N deposition levels. Total DIN deposition in approximately 82% of the basin area exceeded the critical load of N deposition for semi-natural ecosystems along the basin. On the basin scale, the dominant source of DIN deposition is fertilizer use (40%) relative to livestock (11%), industry (13%), power plant (9%), transportation (9%), and others (18%, which is the sum of contributions from human waste, residential activities, soil, lighting and biomass burning), suggesting that reducing NH 3 emissions from improper fertilizer (including chemical and organic fertilizer) application should be a priority in curbing N deposition. This, together with distinct spatial variations in emission sector contributions to total DIN deposition also suggest that, in addition to fertilizer, major emission sectors in different regions of the basin should be considered when developing synergistic control measures. Copyright © 2017. Published by Elsevier Ltd.

  17. The intimate genetics of Drosophila fertilization

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  19. CAN CHILD-CARE SUPPORT POLICIES HALT DECREASING FERTILITY?

    Directory of Open Access Journals (Sweden)

    Masaya Yasuoka

    2013-04-01

    Full Text Available Some earlier papers examine whether child allowances can raise fertility or not in an endogenous fertility model with a defined contribution pension system. They derive that a child allowance can raise fertility. This paper is aimed at deriving the level of child allowances or education subsidies to make the pension system sustainable. A child allowance can raise fertility instantaneously. However, in the long run, fertility might continue decreasing and the pension system might not be sustainable if less child allowance is provided. In a defined benefit system, tax burdens for pension benefits are heavy in an aging society with fewer children. A heavy tax burden reduces the household income and then decreases fertility. Therefore, child allowances must be provided to halt decreasing fertility in the long run. Nevertheless, given parametric conditions, education subsidy of more than a certain level can not halt the decrease of fertility in the long run.

  20. Effect of Number of Spermatozoa, Oviduct Condition and Timing of Artificial Insemination on Fertility and Fertile Period of Kampung Rooster Spermatozoa

    Directory of Open Access Journals (Sweden)

    DM Saleh

    2012-01-01

    Full Text Available Abstract. This study was carried out to determine the optimum fertility and fertile period using the number of spermatozoa, oviduct condition and timing of insemination of native rooster spermatozoa. Ninety six commercial Isa brown pullets and nine kampung roosters were used in this study in a 3×2×2 factorial arrangement with one bird in a cage constituting a unit. The factor levels were the number of spermatozoa (50, 100 and 150 million/0.1 ml, oviduct condition (hard-shelled eggs and free hard-shelled eggs, and timing of artificial insemination (in the morning, at 7 AM and in the afternoon, at 4 PM.  The results showed that among the treatments there was no significant interaction to fertility and fertile period. Insemination with 50 million sperm number seemed to be the same result with the other 2 treatments. Oviduct condition had a highly significant difference on fertility and fertile period percentage, and timing of insemination did not differ between morning and afternoon.  In conclusion, the only oviduct condition (free hard-shelled eggs was the best results for insemination in terms of fertility and fertile period of native roosters.  It is recommended that for the maximum fertility and fertile period, hens should be inseminated with 50 million spermatozoa, free of hard-shelled eggs and insemination performed in the morning or in the afternoon.   Keywords: timing of artificial insemination, fertility, fertile period, semen dose, oviduct condition Animal Production 14(1:32-36, January 2012

  1. Reverse survival method of fertility estimation: An evaluation

    Directory of Open Access Journals (Sweden)

    Thomas Spoorenberg

    2014-07-01

    Full Text Available Background: For the most part, demographers have relied on the ever-growing body of sample surveys collecting full birth history to derive total fertility estimates in less statistically developed countries. Yet alternative methods of fertility estimation can return very consistent total fertility estimates by using only basic demographic information. Objective: This paper evaluates the consistency and sensitivity of the reverse survival method -- a fertility estimation method based on population data by age and sex collected in one census or a single-round survey. Methods: A simulated population was first projected over 15 years using a set of fertility and mortality age and sex patterns. The projected population was then reverse survived using the Excel template FE_reverse_4.xlsx, provided with Timæus and Moultrie (2012. Reverse survival fertility estimates were then compared for consistency to the total fertility rates used to project the population. The sensitivity was assessed by introducing a series of distortions in the projection of the population and comparing the difference implied in the resulting fertility estimates. Results: The reverse survival method produces total fertility estimates that are very consistent and hardly affected by erroneous assumptions on the age distribution of fertility or by the use of incorrect mortality levels, trends, and age patterns. The quality of the age and sex population data that is 'reverse survived' determines the consistency of the estimates. The contribution of the method for the estimation of past and present trends in total fertility is illustrated through its application to the population data of five countries characterized by distinct fertility levels and data quality issues. Conclusions: Notwithstanding its simplicity, the reverse survival method of fertility estimation has seldom been applied. The method can be applied to a large body of existing and easily available population data

  2. Fertilizer value of urine in pumpkin (Cucurbita maxima L. cultivation

    Directory of Open Access Journals (Sweden)

    S.K. PRADHAN

    2008-12-01

    Full Text Available The fertilizer value of human urine was compared with mineral fertilizer in pumpkin (Cucurbita maxima cultivation at a dose of 113 kg N ha-1 with no-fertilization used as control. The growth of the vine was better in urine fertilized pumpkins than in mineral fertilized and non-fertilized pumpkins. Total fruit biomass was higher in mineral fertilized plants compared to urine fertilized and non-fertilized pumpkins. Urine fertilized pumpkins may have suffered from lower potassium or higher chloride, thus they produced fewer flowers and fruits. However, total fruit biomass and the number of fruits were slightly higher in urine fertilized plants than in their non-fertilized counterparts, i.e. 17.2 t ha-1 more pumpkin could be produced with urine fertilizer. The microbial hygiene quality as well as the contents of soluble sugars, protein and taste quality were similar in all treatments, but lower nitrate and higher chloride contents were recorded in urine fertilized pumpkins than other treatments. In conclusion, our study shows that the production rate of urine fertilized pumpkins was somewhat lower than mineral fertilized pumpkins but it was higher than non-fertilized pumpkins. The hygienic quality was equally good with all treatments.;

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

    Science.gov (United States)

    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.

  4. Economic recession and fertility in the developed world.

    Science.gov (United States)

    Sobotka, Tomáš; Skirbekk, Vegard; Philipov, Dimiter

    2011-01-01

    This article reviews research on the effects of economic recessions on fertility in the developed world. We study how economic downturns, as measured by various indicators, especially by declining GDP levels, falling consumer confidence, and rising unemployment, were found to affect fertility. We also discuss particular mechanisms through which the recession may have influenced fertility behavior, including the effects of economic uncertainty, falling income, changes in the housing market, and rising enrollment in higher education, and also factors that influence fertility indirectly such as declining marriage rates. Most studies find that fertility tends to be pro-cyclical and often rises and declines with the ups and downs of the business cycle. Usually, these aggregate effects are relatively small (typically, a few percentage points) and of short durations; in addition they often influence especially the timing of childbearing and in most cases do not leave an imprint on cohort fertility levels. Therefore, major long-term fertility shifts often continue seemingly uninterrupted during the recession—including the fertility declines before and during the Great Depression of the 1930s and before and during the oil shock crises of the 1970s. Changes in the opportunity costs of childbearing and fertility behavior during economic downturn vary by sex, age, social status, and number of children; childless young adults are usually most affected. Furthermore, various policies and institutions may modify or even reverse the relationship between recessions and fertility. The first evidence pertaining to the recent recession falls in line with these findings. In most countries, the recession has brought a decline in the number of births and fertility rates, often marking a sharp halt to the previous decade of rising fertility rates.

  5. In vivo fertilization of banana

    Directory of Open Access Journals (Sweden)

    Taliane Leila Soares

    2014-01-01

    Full Text Available The aim of this research was to study the in vivo fertilization process of banana cultivars. The diploid hybrid (AA 091087-01 was the male progenitor. Flower samples were checked for fertilization from the first to the twentieth day after pollination. The size of the diploid ovules increased gradually at the beginning of the seed formation process. On the other hand, in the AAA triploids (Cavendish subgroup, the not fertilized ovules were aborted. In the AAB triploids (Prata subgroup some ovules were fertilized. The flowers of Grand Naine, Nanicão and 'Pacovan' cultivars presented necrosis in the distal part of the ovary on the first day after pollination. Necrosis can hinder pollen tube growth towards the ovule, which might be related to the low seed yield in 'Pacovan' cultivars and to the absence of seeds in the Cavendish subgroup cultivars.

  6. Wealth, fertility and adaptive behaviour in industrial populations

    Science.gov (United States)

    2016-01-01

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

  7. A Decision Support System for Optimum Use of Fertilizers

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Hoskinson; J. R. Hess; R. K. Fink

    1999-07-01

    The Decision Support System for Agriculture (DSS4Ag) is an expert system being developed by the Site-Specific Technologies for Agriculture (SST4Ag) precision farming research project at the INEEL. DSS4Ag uses state-of-the-art artificial intelligence and computer science technologies to make spatially variable, site-specific, economically optimum decisions on fertilizer use. The DSS4Ag has an open architecture that allows for external input and addition of new requirements and integrates its results with existing agricultural systems' infrastructures. The DSS4Ag reflects a paradigm shift in the information revolution in agriculture that is precision farming. We depict this information revolution in agriculture as an historic trend in the agricultural decision-making process.

  8. A Decision Support System for Optimum Use of Fertilizers

    Energy Technology Data Exchange (ETDEWEB)

    Hoskinson, Reed Louis; Hess, John Richard; Fink, Raymond Keith

    1999-07-01

    The Decision Support System for Agriculture (DSS4Ag) is an expert system being developed by the Site-Specific Technologies for Agriculture (SST4Ag) precision farming research project at the INEEL. DSS4Ag uses state-of-the-art artificial intelligence and computer science technologies to make spatially variable, site-specific, economically optimum decisions on fertilizer use. The DSS4Ag has an open architecture that allows for external input and addition of new requirements and integrates its results with existing agricultural systems’ infrastructures. The DSS4Ag reflects a paradigm shift in the information revolution in agriculture that is precision farming. We depict this information revolution in agriculture as an historic trend in the agricultural decision-making process.

  9. Artificial fertilization by intracytoplasmic sperm injection in a teleost fish, the medaka (Oryzias latipes).

    Science.gov (United States)

    Otani, Satoshi; Iwai, Toshiharu; Nakahata, Shingo; Sakai, Chiharu; Yamashita, Masakane

    2009-01-01

    Intracytoplasmic sperm injection (ICSI) is a technique that has been successfully used for assisting reproduction in mammals. However, this method is still not reliable in nonmammalian species, including teleosts. We succeeded in producing medaka individuals by ICSI with a rate of 13.4% (28 hatched embryos out of 209 eggs fertilized by ICSI), the best value reported so far in teleosts, including zebrafish and Nile tilapia. Although the technique was based on that developed for mammalian eggs, some critical modifications were made to adjust it to the medaka egg, which has a thick and hard envelope (the chorion) and a single sperm entry site (the micropyle). Medaka ICSI was performed by injecting a demembranated spermatozoon into an egg cytoplasm through the micropyle 10-15 sec after egg activation induced by a piezo-actuated vibration, the site and timing of sperm penetration being consistent with those in normal fertilization in medaka. To increase the efficiency of ICSI in medaka, we found that the fertilization by ICSI should precisely mimic the fertilization by insemination with intact sperm, both spatially and temporally. The success rate of ICSI was highly variable in batches of eggs (ranging from 0% to 56%), suggesting that the conditions of eggs are important factors in stabilizing the production of individuals by ICSI. The success in medaka ICSI provides a basis for future research to understand the basic mechanisms in gamete biology of teleosts as well as for development of new technology that can yield valuable applications in fisheries science.

  10. Fertility drugs and cancer: a guideline.

    Science.gov (United States)

    2016-12-01

    Methodological limitations in studying the association between the use of fertility drugs and cancer include the inherent increased risk of cancer in women who never conceive, the low incidence of most of these cancers, and that the age of diagnosis of cancer typically is many years after fertility drug use. Based on available data, there does not appear to be a meaningful increased risk of invasive ovarian cancer, breast cancer, or endometrial cancer following the use of fertility drugs. Several studies have shown a small increased risk of borderline ovarian tumors; however, there is insufficient consistent evidence that a particular fertility drug increases the risk of borderline ovarian tumors, and any absolute risk is small. Given the available literature, patients should be counseled that infertile women may be at an increased risk of invasive ovarian, endometrial, and breast cancer; however, use of fertility drugs does not appear to increase this risk. Copyright © 2016. Published by Elsevier Inc.

  11. Analysis of factors which limited the spatial variation of barley yield on the forest-steppe chernozems of Kursk region

    Science.gov (United States)

    Belik, Anton; Vasenev, Ivan; Jablonskikh, Lidia; Bozhko, Svetlana

    2017-04-01

    The crop yield is the most important indicator of the efficiency of agricultural production. It is the function that depends on a large number of groups of independent variables, such as the weather, soil fertility and overall culture agriculture. A huge number of combinations of these factors contribute to the formation of high spatial variety of crop yields within small areas, includes the slope agrolandscapes in Kursk region. Spatial variety of yield leads to a significant reduction in the efficiency of agriculture. In this connection, evaluation and analysis of the factors, which limits the yield of field crops is a very urgent proble in agroecology. The research was conducted in the period of 2003-2004 on a representative field. The typical and leached chernozems with the varying thickness and of erosion degree are dominated in soil cover. At the time of field research studied areas were busy by barley. The reseached soils have an average and increased fertility level. Chernozem typical full-face, and the leached contain an average of 4.5-6% humus, close to neutral pH, favorable values of physico-chemical parameters, medium and high content of nutrients. The eroded chernozems differs agrogenic marked declining in fertility parameters. The diversity of meso- and micro-relief in the fields and soil cover influence to significant spatial variety of fertility. For example the content of nutrients in the soil variation can be up to 5-fold level. High spatial heterogeneity of soils fertility ifluence to barley yield variety. During research on the productivity of the field varied in the range of 20-43 c/ha, and 7-44 c/ha (2004). Analysis of the factors, which limited the yield of barley, showed that the first priorities occupy unregulated characterises: slope angle and the classification of soils (subtype and race of chernozem and the difference in the degree of erosion), which determines the development of erosion processes and redistribution available to plants

  12. Europe the continent with the lowest fertility

    NARCIS (Netherlands)

    Baird, D. T.; Collins, J.; Evers, J. L. H.; Leridon, H.; Lutz, W.; Velde, E. Te; Thevenon, O.; Crosignani, P. G.; Devroey, P.; Diedrich, K.; Fauser, B. C. J. M.; Fraser, L.; Geraedts, J. P. M.; Gianaroli, L.; Glasier, A.; Sunde, A.; Tarlatzis, B.; Van Steirteghem, A.; Veiga, A.

    2010-01-01

    INTRODUCTION: Although fertility rates are falling in many countries, Europe is the continent with the lowest total fertility rate (TFR). This review assesses trends in fertility rates, explores possible health and social factors and reviews the impact of health and social interventions designed to

  13. MULTIFUNCTION MICROBIAL FERTILIZER AS A SUBSTITUTE INORGANIC FERTILIZER ON SOYBEAN-CORN INTERCROPPING SYSTEM

    Directory of Open Access Journals (Sweden)

    Bambang Rudianto W

    2015-07-01

    Full Text Available This study aims to determine ability of Microbial Fertilizer Multipurpose (PMMG as substitution use of inorganic fertilizers, corn cropping system intercropped with soybeans in order to procure seeds of soybean varieties Mulyo Willis. Research conducted at experimental field of Faculty of Agriculture in village Karangwangkal, Purwokerto, from March to September 2015. This study is a field, which was compiled using split plot design 2 x 3. Data obtained were analyzed using F test If test results showed no significant differences between treatment then continued with Duncan Multiple Range Test (DMRT at the level of accuracy of 95 percent. Results showed: PMMG applications provide better growth of soybean and corn, on soybean growth 29.4 percent and yield 20.8 percent equivalent to 3.36 ku seeds per ha, while in corn promote growth 37.1 percent and yield 16.2 percent equivalent to 1.4 tons seed per ha. While ½ dose treatment with addition NPK recommendations PMMG not reduce growth and yield of corn and soybeans. PMMG application can substitute ½ dose NPK fertilizer recommendations, with land equivalent ratio 1.61. LER is no different from fertilization treatment according to recommendations, which 1.78.

  14. Prediction of porcine male fertility

    NARCIS (Netherlands)

    Broekhuijse, M.L.W.J.|info:eu-repo/dai/nl/313871728

    2012-01-01

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

  15. Fertility outcomes in asthma

    DEFF Research Database (Denmark)

    Gade, Elisabeth Juul; Thomsen, Simon Francis; Lindenberg, Svend

    2016-01-01

    Evidence is increasing of an association between asthma and aspects of female reproduction. However, current knowledge is limited and furthermore relies on questionnaire studies or small populations. In a prospective observational cohort study to investigate whether time to pregnancy, the number...... of fertility treatments, and the number of successful pregnancies differ significantly between women with unexplained infertility with and without asthma.245 women with unexplained infertility (aged 23-45 years) underwent questionnaires and asthma and allergy testing while undergoing fertility treatment. 96...... women entering the study had either a former doctor's diagnosis of asthma or were diagnosed with asthma when included. After inclusion they were followed for a minimum of 12 months in fertility treatment, until they had a successful pregnancy, stopped treatment, or the observation ended.The likelihood...

  16. Fertility preservation 2

    Science.gov (United States)

    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

  17. Iron fertilization enhanced net community production but not downward particle flux during the Southern Ocean iron fertilization experiment LOHAFEX

    Digital Repository Service at National Institute of Oceanography (India)

    Martin, P.; Loeff, M.M.R. van der.; Cassar, N.; Vandromme, P.; d'Ovidio, F.; Stemmann, L.; Rengarajan, R.; Soares, M.A.; Gonzalez, H.E.; Ebersbach, F.; Lampitt, R.S.; Sanders, R.; Barnett, B.A.; Smetacek, V.; Naqvi, S.W.A.

    A closed eddy core in the Subantarctic Atlantic Ocean was fertilized twice with two tons of iron (as FeSO4), and the 300 km2 fertilized patch was studied for 39 days to test whether fertilization enhances downward particle flux...

  18. Fertility treatment in obese women

    NARCIS (Netherlands)

    Koning, A.M.H.

    2015-01-01

    Overweight and obesity are increasing worldwide. This has major adverse consequences for health in general and fertility in women in particular. With the increasing number of women in reproductive age being obese, there is also an increasing need for fertility treatment. And with more pregnant women

  19. Dry limit to photosynthesis and cyanobacterial spatial pattern in the Atacama Desert

    Science.gov (United States)

    Warren-Rhodes, K. A.; Pointing, S. B.; Ewing, S.; Lacap, D.; Gomez-Silva, B.; Amundson, R.; Friedmann, E. I.; McKay, C. P.

    2005-12-01

    Hypolithic autotrophs inhabit translucent rocks in the world`'s most extreme hot and cold deserts. Across a rainfall gradient in the Atacama, we measured a three-fold decline in the molecular diversity of cyanobacterial communities and a drop in their abundance from 28% in relatively wet sites to 0.08% in the driest core. Like plants, hypoliths appear to exhibit traits of self-organized patchiness (aggregated spatial patterns) that tightly correlate with rainfall. Rare cyanobacteria in the core live slowly (3,200 y turnover times) and survive in spatially isolated patches of self-augmented fertility, with the dry limit to their survival occurring at ~Mars but may have existed in rare oases in the past. The spatial distributions of terrestrial desert microbes should be considered in the remote search for life on Mars.

  20. Fabrication and evaluation of variable rate fertilizer system

    Directory of Open Access Journals (Sweden)

    A Damirchi

    2015-09-01

    Full Text Available Introduction: In conventional farming, the soil and crop are considered uniform in different locations of the farm and the fertilizers are applied according to the average of soil needs with an additional percentage for safety (Loghavi, 2003. Non-essential chemical fertilizers in the field have harmful effects and social, economic and environmental concerns will increase. Many fertilizers go into the surface waters and ground waters and cause poisoning and environmental pollution without being absorbed by the plants. In variable rate technology, the soil fertilizer needs a map of all parts of the farm which is prepared with the GIS system. This map is uploaded on the computer before variable rate fertilizer machine starts. The computer continually controls the fertilizing rate for each part of the farm using a fertilizing map and global positioning system. The purpose of this study is to construct and evaluate a map-based variable rate fertilizer system that can be installed on a common fertilizer in Iran to be used as a variable rate system. Materials and methods: In common variable rate fertilizers, the rotational speed change of the distributor shaft is used to apply fertilizers. In this way, a DC motor is assembled on the main shaft of all distributors, which reduces the fertilizing accuracy. The reason for this is that there is no separation for units along the width of the fertilizer. Therefore, we used one DC motor for each distributor and another motor to rotate the agitator in the tank. System Set up: To design and select a suitable engine, the required torque for the rotation distributor shaft was measured by a torque meter and the amount of 2.1 Nm was acquired for that. With regard to the maximum rate of nitrogen fertilizer for land and tractor speed at the time of fertilizing, the order of 350 kg per hectare and 8 km per hour, the maximum distributor shaft speed and power required to rotate distributor shaft were calculated to be 55

  1. Global fertility and population trends.

    Science.gov (United States)

    Bongaarts, John

    2015-01-01

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

  2. Agroforestry: A second soil fertility paradigm? A case of soil fertility management in Western Kenya

    NARCIS (Netherlands)

    Mango, Nelson; Hebinck, Paul

    2016-01-01

    This paper explores the claim whether agro-forestry is a second soil fertility
    paradigm. The answer to this question, however, is not unequivocal. Farmers in
    Western Kenya generally do not apply fertiliser and rather rely on many soil fertility replenishment (SFR) strategies. Scientists

  3. Genetic analysis of fertility restoration genes for WAtype cytoplasmic ...

    African Journals Online (AJOL)

    Pollen staining test with 1% I2KI solution showed segregation ratio of 15:1 (fertile: sterile), representing two nuclear independent dominant genes controlling the trait carried by fertile parent DN-33-18. Segregation for spikelet fertility in F2 confirmed the results of pollen fertility test. Molecular tagging of fertility restorer genes ...

  4. Cohort Fertility Patterns in the Nordic Countries

    Directory of Open Access Journals (Sweden)

    Gunnar Andersson

    2009-04-01

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

  5. Assessment of testicular volume: A comparison of fertile and sub-fertile West African men

    Directory of Open Access Journals (Sweden)

    K.H. Tijani

    2014-09-01

    Conclusion: Testicular volume on scrotal ultrasound correlates well with severity of oligospermia in men with sub-fertility. While the critical mean testicular volume necessary for adequate spermatogenesis has not been determined, it appears there is an optimal testicular volume of 18–20 ml at which spermatogenesis is at its peak in sub-fertile Nigerian men.

  6. Fertilizer application and root development analyzed by neutron imaging

    International Nuclear Information System (INIS)

    Nihei, Naoto; Tanoi, Keitaro; Nakanishi, Tomoko M.

    2013-01-01

    We studied the development of the soybean root system under different application of fertilizer applying neutron imaging technique. When neutron beam was irradiated, the root image as well as fertilizer imbedded in a thin aluminum container was clearly projected, since water amount in roots are higher than that in soil. Through image analysis, the development of root system was studied under different application of the fertilizer. The development of a main root with lateral roots was observed without applying fertilizer. When the fertilizer was homogeneously supplied to the soil, the morphological development of the root showed the similar pattern to that grown without fertilizer, in different to the amount of the fertilizer. In the case of local application of the fertilizer, lateral position or downward to the main root, the inhibition of the root growth was observed, suggesting that the localization of the fertilizer is responsible for reduction of the soybean yield. (author)

  7. Zinc fertilization of flooded rice

    International Nuclear Information System (INIS)

    1981-02-01

    Local scientists studied Zn fertilization of flooded rice soils in Bangladesh, India, Indonesia, the Republic of Korea, Egypt, the Philippines, Thailand and Turkey. Diagnosis of Zn deficiency was carried out for submerged rice soils. Soil maps were prepared, designating areas as low, medium and high in Zn, based on Zn extraction with DTPA and HCl solutions and on rice leaf analysis. The effectiveness of various Zn fertilizer sources and methods of application in field and greenhouse experiments was measured, using 65 Zn. The percent Zn derived from fertilizer was shown to be a much more sensitive measure of efficiency than yield or total uptake

  8. Slow fertilization of stickleback eggs: the result of sexual conflict?

    Directory of Open Access Journals (Sweden)

    Frommen Joachim G

    2006-05-01

    Full Text Available Abstract Background The fertilization success in sperm competition in externally fertilizing fish depends on number and quality of sperm. The time delay between sequential ejaculations may further influence the outcome of sperm competition. Such a time interval can load the raffle over fertilization if fertilization takes place very fast. Short fertilization times are generally assumed for externally fertilizing fish such as the three-spined stickleback (Gasterosteus aculeatus. In this pair-spawning fish, territorial males often try to steal fertilizations in nests of neighbouring males. This sneaking behaviour causes sperm competition. Sneakers will only get a share of paternity when eggs are not fertilized immediately after sperm release. Contrary to males, females may be interested in multiple paternity of their clutch of eggs. There thus may be a sexual conflict over the speed of fertilization. Results In this study we used two different in vitro fertilization experiments to assess how fast eggs are fertilized in sticklebacks. We show that complete fertilization takes more than 5 min which is atypically long for externally fertilizing fishes. Conclusion This result suggests that the time difference does not imply high costs to the second stickleback male to ejaculate. Slow fertilization (and concomitant prolonged longevity of sperm may be the result of sexual conflict in which females aimed at complete fertilization and/or multiple paternity.

  9. Estimation of natural radioactivity in different fertilizers

    International Nuclear Information System (INIS)

    Gupta, Monika; Chauhan, Pooja; Chauhan, R.P.; Sonkawade, R.G.; Kant, K.

    2011-01-01

    Fertilizers have become essential to the agricultural field all over the world. The natural radionuclides of fertilizers consist mainly of 226 Ra, 232 Th, isotopes with their decay products. The level of activity concentration of radionuclides in phosphate fertilizers provides useful information in the monitoring of environmental contamination. The concepts of natural radiation are essential for radiation protection purpose. Radionuclides present in fertilizers affect the common people and farmers immensely. They are produced and used worldwide in increasing quantities to replenish natural nutrients depleted from soils because of forming and erosion. However, the mining, processing and use of fertilizer materials in massive quantities redistribute radioactive trace elements throughout the environment, principally uranium, radium, radium decay products. The agricultural phosphate fertilizer industries use raw materials that consist of phosphate rocks, phosphoric acid, ammonium phosphate. The level of activity concentration of radionuclides in different fertilizers provides useful information in the monitoring of environmental contamination. Radiological impacts of phosphate rocks mining and manufacture could be significant due to the elevated radioactivity contents of the naturally occurring radioactive materials (NORM), such as 238 U series, 232 Th series and 40 K, in some phosphate deposits. The concepts of natural radiation are essential for radiation protection purpose. This paper emphasis on the public risk assessment in an integrated manner assessing doses to members of the public via the atmospheric aquatic and secondary pathways. In the present study radioactivity in different fertilizer samples, which are widely used in Indian fields, was determined. The experimental work includes the measurements of 226 Ra, 232 Th and 40 K using gamma spectrometry and radon concentration and exhalation rates measurement using solid state nuclear track detectors to asses a

  10. Immunosuppressive drugs and fertility

    OpenAIRE

    Leroy, Clara; Rigot, Jean-Marc; Leroy, Maryse; Decanter, Christine; Le Mapihan, Kristell; Parent, Anne-Sophie; Le Guillou, Anne-Claire; Yakoub-Agha, Ibrahim; Dharancy, Sébastien; Noel, Christian; Vantyghem, Marie-Christine

    2015-01-01

    Immunosuppressive drugs are used in the treatment of inflammatory and autoimmune diseases, as well as in transplantation. Frequently prescribed in young people, these treatments may have deleterious effects on fertility, pregnancy outcomes and the unborn child. This review aims to summarize the main gonadal side effects of immunosuppressants, to detail the effects on fertility and pregnancy of each class of drug, and to provide recommendations on the management of patients who are seen prior ...

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

    Science.gov (United States)

    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.

  12. Use of isotopically labeled fertilizer to trace nitrogen fertilizer contributions to surface, soil, and ground water

    Science.gov (United States)

    Wilkison, D.H.; Blevins, D.W.; Silva, S.R.

    2000-01-01

    The fate and transport of a single N fertilizer application through plants, soil, runoff, and the unsaturated and saturated zones was determined for four years at a field site under continuous corn (Zea mays L.) management. Claypan soils, which underlie the site, were hypothesized to restrict the movement of agrichemicals from the soil surface to ground water. However, N fertilizer moved rapidly through preferential flow paths in the soil and into the underlying glacial till aquifer. Most N transport occurred during the fall and winter when crops were not available to use excess N. Forty months after application, 33 percent of the fertilizer had been removed by grain harvests, 30 percent had been transpired to the atmosphere, and 33 percent had migrated to ground water. Although runoff volumes were 50 percent greater than infiltration, less than 2 percent of the fertilizer was lost to runoff. Small measured denitrification rates and large measured dissolved oxygen concentrations in ground water favor the long-term stability of NO3-1 in ground water. Successive fertilizer applications, in areas that lack the ability to moderate N concentrations through consumptive N reactions, risk the potential of N-saturated ecosystems.

  13. Fertilizers applied to certified organic tomato culture

    International Nuclear Information System (INIS)

    Martins, T.C.G.; De Nadai Fernandes, E.A.; Ferrari, A.A.; Bacchi, M.A.; Tagliaferro, F.S.

    2010-01-01

    The tomato culture demands large quantities of mineral nutrients, which are supplied by synthetic fertilizers in the conventional cultivation system. In the organic cultivation system only alternative fertilizers are allowed by the certifiers and accepted as safe for humans and environment. The chemical composition of rice bran, oyster flour, cattle manure and ground charcoal, as well as soils and tomato fruits were evaluated by instrumental neutron activation analysis (INAA). The potential contribution of organic fertilizers to the enrichment of chemical elements in soil and their transfer to fruits was investigated using concentration ratios for fertilizer and soil samples, and also for soil and tomato. Results evidenced that these alternative fertilizers could be taken as important sources of Br, Ca, Ce, K, Na and Zn for the organic tomato culture. (author)

  14. Fertility preservation in Turner syndrome.

    Science.gov (United States)

    Grynberg, Michaël; Bidet, Maud; Benard, Julie; Poulain, Marine; Sonigo, Charlotte; Cédrin-Durnerin, Isabelle; Polak, Michel

    2016-01-01

    Premature ovarian insufficiency is a relatively rare condition that can appear early in life. In a non-negligible number of cases the ovarian dysfunction results from genetic diseases. Turner syndrome (TS), the most common sex chromosome abnormality in females, is associated with an inevitable premature exhaustion of the follicular stockpile. The possible or probable infertility is a major concern for TS patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The severely reduced follicle pool even during prepubertal life represents the major limit for fertility preservation and is the root of numerous questions regarding the competence of gametes or ovarian tissue crybanked. In addition, patients suffering from TS show higher than usual rates of spontaneous abortion, fetal anomaly, and maternal morbidity and mortality, which should be considered at the time of fertility preservation and before reutilization of the cryopreserved gametes. Apart from fulfillment of the desire of becoming genetic parents, TS patients may be potential candidates for egg donation, gestational surrogacy, and adoption. The present review discusses the different options for preserving female fertility in TS and the ethical questions raised by these approaches. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  15. Diverging patterns of fertility decline in Uruguay

    Directory of Open Access Journals (Sweden)

    Mathías Nathan

    2016-03-01

    Full Text Available Background: The total fertility rate (TFR in Uruguay fell from 2.5 to 1.9 children per woman between 1996 and 2011. However, no study to date has examined the decline of the TFR by observing changes in fertility patterns by birth order. Objective: The main aim of this study is to analyze recent changes in fertility level and timing of childbearing by birth order in Uruguay. Methods: We estimate unconditional and conditional age- and birth-order-specific fertility rates for 1996-2011 using data from vital statistics, population census, and national population estimates. Additionally, three period summary measures of birth-order-specific fertility quantum are calculated: TFR, PATFR and TFRp*. Timing changes by birth order are examined with MAB and TMAB, focusing on MAB1 and its standard deviation and comparing their evolutions in Uruguay with those of selected countries. Results: Fertility decline fits a parity-specific stopping model with a moderate increase in the mean ages of first, second, and third births. The distribution of conditional fertility rates for first and second births depicts an asymmetric bimodal shape linked to the increasing heterogeneity of the timing of childbearing. Compared to countries with similar fertility trends, heterogeneity in the age at first birth in Uruguay is remarkably high. Conclusions: Previous studies suggest that heterogeneity in first and second birth timing is related to structural social inequalities, as women from lower social strata have not significantly changed the age at which they bear a first child, whereas women of middle to high social strata have started to postpone it. The new evidence reinforces the idea that postponement transition in Uruguay cannot be studied without considering this consolidation of social status polarization in fertility timing.

  16. Female labour force participation and fertility.

    Science.gov (United States)

    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.

  17. Criteria for Selecting Optimal Nitrogen Fertilizer Rates for Precision Agriculture

    Directory of Open Access Journals (Sweden)

    Bruno Basso

    Full Text Available Yield rates vary spatially and maps produced by the yield monitor systems are evidence of the degree of withinfield variability. The magnitude of this variability is a good indication of the suitability of implementing a spatially variable management plan. Crop simulation models have the potential to integrate the effects of temporal and multiple stress interaction on crop growth under different environmental and management conditions. The strength of these models is their ability to account for stress by simulating the temporal interaction of stress on plant growth each day during the season. The objective of paper is to present a procedure that allows for the selection of optimal nitrogen fertilizer rates to be applied spatially on previously identified management zones through crop simulation modelling. The integration of yield maps, remote sensing imagery, ground truth measurements, electrical resistivity imaging allowed for the identifications of three distinct management zones based on their ability to produce yield and their stability over time (Basso et al., 2009. After validating the model, we simulated 7 N rates from 0 to 180 kg N/ha with a 30 kg N/ha increment. The model results illustrate the different N responses for each of the zone. The analysis allowed us to identify the optimal N rate for each of the zone based on agronomic, economic and environmental sustainability of N management.

  18. Criteria for Selecting Optimal Nitrogen Fertilizer Rates for Precision Agriculture

    Directory of Open Access Journals (Sweden)

    Bruno Basso

    2009-12-01

    Full Text Available Yield rates vary spatially and maps produced by the yield monitor systems are evidence of the degree of withinfield variability. The magnitude of this variability is a good indication of the suitability of implementing a spatially variable management plan. Crop simulation models have the potential to integrate the effects of temporal and multiple stress interaction on crop growth under different environmental and management conditions. The strength of these models is their ability to account for stress by simulating the temporal interaction of stress on plant growth each day during the season. The objective of paper is to present a procedure that allows for the selection of optimal nitrogen fertilizer rates to be applied spatially on previously identified management zones through crop simulation modelling. The integration of yield maps, remote sensing imagery, ground truth measurements, electrical resistivity imaging allowed for the identifications of three distinct management zones based on their ability to produce yield and their stability over time (Basso et al., 2009. After validating the model, we simulated 7 N rates from 0 to 180 kg N/ha with a 30 kg N/ha increment. The model results illustrate the different N responses for each of the zone. The analysis allowed us to identify the optimal N rate for each of the zone based on agronomic, economic and environmental sustainability of N management.

  19. Criteria for Selecting Optimal Nitrogen Fertilizer Rates for Precision Agriculture

    Directory of Open Access Journals (Sweden)

    Francesco Basso

    2011-02-01

    Full Text Available Yield rates vary spatially and maps produced by the yield monitor systems are evidence of the degree of withinfield variability. The magnitude of this variability is a good indication of the suitability of implementing a spatially variable management plan. Crop simulation models have the potential to integrate the effects of temporal and multiple stress interaction on crop growth under different environmental and management conditions. The strength of these models is their ability to account for stress by simulating the temporal interaction of stress on plant growth each day during the season. The objective of paper is to present a procedure that allows for the selection of optimal nitrogen fertilizer rates to be applied spatially on previously identified management zones through crop simulation modelling. The integration of yield maps, remote sensing imagery, ground truth measurements, electrical resistivity imaging allowed for the identifications of three distinct management zones based on their ability to produce yield and their stability over time (Basso et al., 2009. After validating the model, we simulated 7 N rates from 0 to 180 kg N/ha with a 30 kg N/ha increment. The model results illustrate the different N responses for each of the zone. The analysis allowed us to identify the optimal N rate for each of the zone based on agronomic, economic and environmental sustainability of N management.

  20. Declining world fertility: trends, causes, implications.

    Science.gov (United States)

    Tsui, A O; Bogue, D J

    1978-10-01

    This Bulletin examines the evidence that the world's fertility has declined in recent years, the factors that appear to have accounted for the decline, and the implications for fertility and population growth rates to the end of the century. On the basis of a compilation of estimates available for all nations of the world, the authors derive estimates which indicate that the world's total fertility rate dropped from 4.6 to 4.1 births per woman between 1968 and 1975, thanks largely to an earlier and more rapid and universal decline in the fertility of less developed countries (LDCs) than had been anticipated. Statistical analysis of available data suggests that the socioeconomic progress made by LDCs in this period was not great enough to account for more than a proportion of the fertility decline and that organized family planning programs were a major contributing factor. The authors' projections, which are compared to similar projections from the World Bank, the United Nations, and the U.S. Bureau of the Census, indicate that, by the year 2000, less than 1/5 of the world's population will be in the "red danger" circle of explosive population growth (2.1% or more annually); most LDCs will be in a phase of fertility decline; and many of them -- along with most now developed countries -- will be at or near replacement level of fertility. The authors warn that "our optimistic prediction is premised upon a big IF -- if (organized) family planning (in LDCs) continues. It remains imperative that all of the developed nations of the world continue their contribution to this program undiminished."

  1. Radioactivity in chemical and organic fertilizer used in Egypt

    International Nuclear Information System (INIS)

    Abbady, A.G.E.; Yousef, A.M.M.; Abbady, A.; El-Taher, A.

    2005-01-01

    The Egypt Chemical factories (ECF); such as Talkha, Sues, Abo Qeyer, Kafer Elzayat, and Assuit factories, produces and markets a range of phosphate based fertilizers, including Simple Super Phosphate (SSP) fertilizer, Triple Super Phosphate (TSP) fertilizer and Urea. Phosphate fertilizers produced by ECF are derived from phosphate ore. In addition to phosphate minerals, these ores can contain significant amounts of a wide range of impurities, including heavy metals and naturally occurring radionuclides. This study was carried out to determine the content of radionuclides in fertilizer products produced by ECF and some organic fertilizer (animal manure) includes cow, sheep and chicken fertilizer. In both samples (Chemical and organic fertilizers), the activity concentrations of Ra 2 26 are higher than those Th 2 32. The radioactivity of 226 R a in chemical fertilizers ranged from 21.6 ± 3.6 to 111.2 ± 8.9 Bq kg-1, phosphate fertilizers TSP contained high contents of 226 R a. The average radioactivity of 226 R a in TSP was 79.3 ± 7.4 Bq kg-1, in SSP 51.2 ± 5 Bq kg-1, and in Urea 35.1± 3.5 Bq kg-1. The activity of 232 T h in the different fertilizers ranged from 1.3 ± 1.1 to 9.9 ± 3.2 Bq kg-1,the highest activity observed in SSP fertilizer. The activity of 40 K was found to be great in the TSP fertilizer, which contained a mean activity 478.1± 21.3 Bq kg-1. With respect to organic fertilizers the average radioactivity of 226 R a, 232 T h and 40 K are 40 ± 1.6 Bq kg-1, 3.1± 1.2 and 427.1± 20 Bq kg-1. The data are discussed and compared with those given in the literatures. This study could be useful as baseline data for radiation exposure to fertilizers, and their impact on human health

  2. Determinants of adolescent fertility in Ethiopia

    African Journals Online (AJOL)

    Bernt Lindtjorn

    demographic and economic determinants whereas Bongaarts model was used to determine proximate determinants fertility. ... Organization defines the age group of 10-19 and 15-24 ..... In urban areas, 24% of marital fertility was prevented.

  3. Psychological aspects of male fertility treatment

    DEFF Research Database (Denmark)

    Mikkelsen, Alice Toft; Madsen, Svend Aage Lykke; Humaidan, Peter

    2013-01-01

    To explore and to identify the possible need for psychological communicative support in men undergoing fertility treatment.......To explore and to identify the possible need for psychological communicative support in men undergoing fertility treatment....

  4. ORGANIC FERTILIZER: THE UNDERESTIMATED COMPONENT IN ...

    African Journals Online (AJOL)

    Osondu

    Abstract. Emphasis on increase agricultural productivity of small holder rural peasants from the perspective of soil ... a reward system for farmers and researchers who utilize inorganic fertilizers. .... Some are deregulation of seed and fertilizer.

  5. Basal follicle stimulating hormone and leptin on the day of hCG administration predict successful fertilization in in vitro fertilization

    Directory of Open Access Journals (Sweden)

    Andon Hestiantoro

    2016-04-01

    Full Text Available Background: Successful pregnancy in in vitro fertilization (IVF program depends on multiple factors. This study aimed to determine whether age, body mass index (BMI, basal follicle stimulating hormone (FSH, estradiol, and leptin on the day of trigger ovulation with human chorionic gonadotropin (hCG might be used as predictor for successful oocyte fertilization in in vitro fertilization (IVF program.Methods: This is a cross sectional study conducted in Yasmin Fertility Clinic, Cipto Mangunkusumo Hospital, Jakarta, Indonesia. Forty participating patients underwent IVF program, excluding smokers, patients with diabetic, morbid obesity, and severe oligospermia or azoospermia. Age, BMI, basal FSH, estradiol, leptin on the day of hCG administration, oocyte count on oocyte retrieval, the number of mature oocyte, and fertility rate were analyzed using bivariate and multivariate analysis to determine which eligible factors play role in predicting the successful of fertilization.Results: Significant correlation was found between basal FSH level and serum leptin/oocyte ratio on the day of hCG administration with successful fertilization. We found probability formula as follows: 1/(1+exp –(6.2 - 0.4(leptin serum/oocyte ratio - 0.8(basal FSH, with 77.8% sensitivity, 77.8% specificity, and AUC levels of 85.6% indicating strong predictability. Probability of successful fertilization related to basal FSH level of 5.90 mIU/mL and leptin serum/oocyte ratio of 3.98.Conclusion: The formula consisting of basal FSH and leptin serum/oocyte ratio on the day of trigger ovulation was capable in predicting the probability of successful fertilization in IVF procedure.

  6. Yields, market values and n use efficiency (15n) in flue-cured tobacco influenced by basal fertilization time and n fertilizer

    International Nuclear Information System (INIS)

    Xie Zhijian; Tu Shuxin; Li Jinping; Chen Zhenguo; Xu Rubing; Cao Shiming; Li Jianping; Wang Xuelong; Chen Liangcun; Guo Li; Cao Xianglian; Hu Gongjun; Zhang Yunzheng

    2010-01-01

    A field experiment with 15 N isotope tracing micro-plots was carried out to study the effects of basal N fertilizer application time (0 d, 15 d, 30 d before the transplanting) on the yields, market values and N uptake, utilization and distribution in different organs of flue-cured tobacco (FCT) in two ecological tobacco production areas Zhaojiashan (N 31 degree 28', E 111 degree 15', 903 m above sea level) and Laowan (N 31 degree 27', E 111 degree 14', 1 130 m above sea level)] of Xiangfan city, Hubei province. The results showed that supplying N fertilizer significantly increased the yields and market values of FCT by 13%-40% and 14%-35% for the experimental site of Zhaojiashan (lower altitude ) and Laowan (higher altitude), respectively. Compared to applying basal fertilizer at 0 d before transplanting, applying basal fertilizer at 15-30 d before transplanting increased the market values by 10%-30% (P<0.05). And early application of basal N fertilizer (30 d before transplanting) increased N accumulation by 8%-26% as compared with that of applying basal N fertilizer at 0 d or 15 d before transplanting in the two ecological areas. There was no significant effects of basal N application time on N fertilizer efficiency in lower altitude site, but increasing by 3%-6% in higher altitude site. The proportion of fertilizer N to total N in FCT decreased by 8%-32% in lower altitude, but increased by 25%-32% in higher altitude when basal N fertilizer was supplied at 30d before transplanting., These results indicated that properly earlier supplication of basal N fertilizer could improve the N fertilizer efficiency, and thus increase the yields and market values of FCT, especially in higher altitude areas with less sunshine and lower temperature. (authors)

  7. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik

    1999-01-01

    To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....

  8. Wealth, intelligence, politics and global fertility differentials.

    Science.gov (United States)

    Meisenberg, Gerhard

    2009-07-01

    Demographic trends in today's world are dominated by large fertility differentials between nations, with 'less developed' nations having higher fertility than the more advanced nations. The present study investigates whether these fertility differences are related primarily to indicators of economic development, the intellectual level of the population, or political modernity in the form of liberal democracy. Results obtained with multiple regression, path models and latent variable models are compared. Both log-transformed GDP and measures of intelligence independently reduce fertility across all methods, whereas the effects of liberal democracy are weak and inconsistent. At present rates of fertility and mortality and in the absence of changes within countries, the average IQ of the young world population would decline by 1.34 points per decade and the average per capita income would decline by 0.79% per year.

  9. Plant-based fertilizers for organic vegetable production

    DEFF Research Database (Denmark)

    Sørensen, Jørn Nygaard; Thorup-Kristensen, Kristian

    2011-01-01

    To ensure high yield and quality in organic vegetable production, crops often require additional fertilizer applied during the season. Due to the risk of contamination of edible plant products from slurry, plant-based fertilizers may be used as an alternative. The purpose of our work was to develop...... fertility, the term “mobile green manures” is used for green-manure crops that are harvested in one field and then moved as a whole and used as fertilizer in other fields. To further investigate mobile-green-manure crops for use as efficient fertilizers, pot and field experiments were conducted...... with cauliflower (Brassica oleracea botrytis) and kale (Brassica oleracea sabellica) supplied with organic matter consisting of a wide range of plant species with varying nutrient concentrations. Further, field experiments were conducted with leek (Allium porrum) and celery (Apium graveolens dulce) supplied...

  10. Fertilization Mechanisms in Flowering Plants.

    Science.gov (United States)

    Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M

    2016-02-08

    Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells, they interact and fuse with two dimorphic female gametes (the egg and the central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here, we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion, as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca(2+) is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes, including mammals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Crystallographic properties of fertilizer compounds

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, A.W.; Dillard, E.F.; Thrasher, R.D.; Waerstad, K.R.; Hunter, S.R.; Kohler, J.J.; Scheib, R.M.

    1991-02-01

    This bulletin is a compilation of crystallographic data collected at NFERC on 450 fertilizer-related compounds. In TVA's fertilizer R and D program, petrographic examination, XRD, and infrared spectroscopy are combined with conventional chemical analysis methods in identifying the individual compounds that occur in fertilizer materials. This handbook brings together the results of these characterization studies and supplemental crystallographic data from the literature. It is in one-compound-per-page, loose-leaf format, ordered alphabetically by IUPAC name. Indexes provided include IUPAC name, formula, group, alternate formula, synonyms, x-ray data, optical data. Tables are given for solids, compounds in commercial MAP and DAP, and matrix materials in phosphate rock.

  12. Soil compaction and fertilization in soybean productivity

    Directory of Open Access Journals (Sweden)

    Beutler Amauri Nelson

    2004-01-01

    Full Text Available Soil compaction and fertilization affect soybean development. This study evaluated the effects of soil compaction and fertilization on soybean (Glycine max cv. Embrapa 48 productivity in a Typic Haplustox under field conditions in Jaboticabal, SP, Brazil. A completely randomized design with a 5 x 2 factorial layout (compaction vs. fertilization, with four replications in each treatment, was employed. Each experimental unit (replicate consisted of a 3.6 m² useful area. After the soil was prepared by cultivation, an 11 Mg tractor passed over it a variable number of times to create five levels of compaction. Treatments were: T0= no compaction, T1= one tractor pass, T2= two, T4= four, and T6= six passes, and no fertilizer and fertilizer to give soybean yields of 2.5 to 2.9 Mg ha-1. Soil was sampled at depths of 0.02-0.05, 0.07-0.10, and 0.15-0.18 m to determine macro and microporosity, penetration resistance (PR, and bulk density (Db. After 120 days growing under these conditions, the plants were analyzed in terms of development (plant height, number of pods, shoot dry matter per plant and weight of 100 seeds and seed productivity per hectare. Soil compaction decreased soybean development and productivity, but this effect was decreased by soil fertilization, showing that such fertilization increased soybean tolerance to soil compaction.

  13. Intergenerational fertility correlations in contemporary developing counties.

    Science.gov (United States)

    Murphy, Michael

    2012-01-01

    To estimate the magnitude of intergenerational continuities in total and effective fertility among women in a group of 46 contemporary developing countries. Information collected from 93,000 women aged 45-49 for estimation of maternal mortality in the demographic and health surveys (DHS) program is analyzed using Pearson product moment intergenerational fertility correlations. A positive but usually small intergenerational correlation is found for both completed fertility (CFS, total number of children born) and effective fertility (EFS, number of children surviving to age of reproduction). Although the developing countries are mainly located in sub-Saharan Africa, a similar pattern appears to hold for the Asian and Latin American countries included. Women in the second generation with no education have a stronger relationship with their parents' fertility than women with some education. The relationship is also stronger in rural than in urban areas and in countries with lower levels of development. Intergenerational correlations of completed fertility in both generations are marginally stronger than for effective fertility largely because the number of a woman's total sibs is more strongly related to her subsequent childbearing than her number of adult sibs. Values of intergenerational correlations for these countries are similar to published values for a number of Western pretransitional populations, but well below values in contemporary developed societies. Copyright © 2012 Wiley Periodicals, Inc.

  14. Fertilizer and briquetting and carbonisation plants

    Energy Technology Data Exchange (ETDEWEB)

    Rangachary, P T

    1984-11-14

    The fertilizer plant and the briquetting and carbonisation plant of the Neyveli Lignite Corporation's complex in Neyveli, Tamil Nadu, India, and the processes used in each to produce fertilizers, smokeless fuels and tar products are described.

  15. Occurrence of priority organic pollutants in the fertilizers, China.

    Science.gov (United States)

    Mo, Ce-Hui; Cai, Quan-Ying; Li, Yun-Hui; Zeng, Qiao-Yun

    2008-04-15

    The use of large quantities of chemical fertilizers is usually associated with environmental problems. A lot of work has been done on the concentrations of heavy metals and radionuclides in chemical fertilizers, but little work has focused on the occurrence of semi-volatile organic compounds (SVOCs). In this study the occurrence of 43 SVOCs listed as priority pollutants in 22 widely used-fertilizers of China was determined by gas chromatography coupled with mass spectrometry. Twenty-six SVOCs were detected with different detection frequencies and concentrations. The most abundant compounds were phthalic acid esters (PAEs; ranging from 1.17 to 2795 microg kg(-1) dry weight, d.w.) and nitroaromatics (up to 9765 microg kg(-1) d.w.), followed by polycyclic aromatic hydrocarbons (PAHs; fertilizers, and the total concentrations of each class of contaminants varied widely, too. The highest levels of sum concentration for 16 PAHs, for 6 PAEs and for nitroaromatics were found in organic fertilizer containing pesticide and soil amendments. Concentrations of SVOCs in coated fertilizers (the controlled release fertilizer with coating) were considerably higher than those in the corresponding fertilizers without coating. The occurrence frequencies of SVOCs in the straight fertilizers (containing only one of the major plant nutrients) were lower than in the other fertilizers.

  16. Isotope technology as applied to studies of soil fertility, nutrient availability and fertilizer use on flooded rice soils

    International Nuclear Information System (INIS)

    Patnaik, S.; Mohanty, S.K.; Dash, R.N.

    1979-01-01

    Research is reviewed on soil fertility and nutrient availability in relation to fertilizer efficiency, especially o stimulated the mineralization of soil N. Losses of added N from oxidation, leaching, denitrification and volatilization could be minimized through placement of N fertilizer in the reduced zone or by the addition of rice straw for rapid immobilization of added N. Fe-P and, to some extent, Al-P provided P to the rice plants, particularly in P-deficient soils. Added phosphates were converted to these forms which, under waterlogged soil conditions, released more P into the soil solution through reductive solubilization of Fe-P and hydrolytic dissolution of Al-P. The rice plants generally absorbed fertilizer N during the vegetative growth period and N mineralized from soil organic matter during the reproductive growth period. 15 N studies indicated higher grain yield and utilization of applied N through fractional application of 70-80% during the vegetative growth period, and the remaining 20-30% top-dressed at the panicle initiation stage. Ammonia-containing and -forming (urea) fertilizers were superior to the nitrate form of N. In field tests, however, the crop recovery of applied N was relatively low. Phosphatic fertilizers were best applied at puddling. In general, water-soluble phosphates were superior to citrate-soluble or insoluble phosphates. The latter could be made as efficient as the water-soluble phosphate, at comparable low rates, by applying to the moist aerobic acid soil 2-3 weeks before flooding and transplanting rice. Tracer studies have been used to evaluate the nutrient-supplying capacity of the soil from the 'A' value concept. 'A' values varied with varying conditions of soil, rate, time and form of fertilizer application. Zn nutrition of the rice plant and fertilizer use with 65 Zn have been studied relatively little. Some lines of future work are suggested

  17. Young women's construction of their post-cancer fertility.

    Science.gov (United States)

    Dryden, Amy; Ussher, Jane M; Perz, Janette

    2014-01-01

    Younger women diagnosed with cancer often face compromised fertility as a result of their treatment. However, previous research has adopted a biomedical model of fertility and utilised hypothetico-deductive research methods which have not allowed for full exploration of women's subjectivity. This study explored younger women's construction of their fertility post-cancer, and their discussions of fertility with healthcare professionals, from a social constructionist epistemology. Semi-structured one-to-one interviews were conducted with eight women aged 18-26, across a variety of cancer types. Foucaultian Discourse Analysis identified three subject positions associated with fertility concerns: 'Inadequate woman: Accepting the motherhood mandate'; 'Adequate woman: Resisting the motherhood mandate'; and 'Survival of the fittest: Woman as genetically defective'. Implications of these subject positions included feelings of inadequacy, fear and devastation; feeling undesirable to romantic partners; and concern about passing on cancer-positive genes. In describing healthcare professional interactions, women adopted positions of 'Satisfied patient'; 'Passive recipient patient'; or 'Resisting the passive patient position'. Accounts of inadequate information provision were associated with anger and frustration, whereas feeling adequately informed was associated with satisfaction at making decisions about fertility preservation. These results suggest that fertility is of importance to young women cancer survivors, and that compromised fertility can negatively impact subjectivity.

  18. Obesity: modern man's fertility nemesis.

    Science.gov (United States)

    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.

  19. [Effect of mineral N fertilizer reduction and organic fertilizer substitution on soil biological properties and aggregate characteristics in drip-irrigated cotton field.

    Science.gov (United States)

    Li, Rui; Tai, Rui; Wang, Dan; Chu, Gui-Xin

    2017-10-01

    A four year field study was conducted to determine how soil biological properties and soil aggregate stability changed when organic fertilizer and biofertilizer were used to reduce chemical fertilizer application to a drip irrigated cotton field. The study consisted of six fertilization treatments: unfertilized (CK); chemical fertilizer (CF, 300 kg N·hm -2 ; 90 kg P2O5 · hm -2 , 60 kg K2 O·hm -2 ); 80% CF plus 3000 kg·hm -2 organic fertilizer (80%CF+OF); 60% CF plus 6000 kg·hm -2 organic fertilizer (60%CF+OF); 80% CF plus 3000 kg·hm -2 biofertilizer (80%CF+BF); and 60% CF plus 6000 kg·hm -2 biofertilizer (60%CF+BF). The relationships among soil organic C, soil biological properties, and soil aggregate size distribution were determined. The results showed that organic fertilizer and biofertilizer both significantly increased soil enzyme activities. Compared with CF, the biofertilizer treatments increased urease activity by 55.6%-84.0%, alkaline phosphatise activity by 53.1%-74.0%, invertase activity by 15.1%-38.0%, β-glucosidase activity by 38.2%-68.0%, polyphenoloxidase activity by 29.6%-52.0%, and arylsulfatase activity by 35.4%-58.9%. Soil enzyme activity increased as the amount of organic fertilizer and biofertilizer increased (i.e., 60%CF+OF > 80%CF+OF, 60%CF+BF > 80%CF+BF). Soil basal respiration decreased significantly in the order BF > OF > CF > CK. Soil microbial biomass C and N were 22.3% and 43.5% greater, respectively, in 60%CF+BF than in CF. The microbial biomass C:N was significantly lower in 60%CF+BF than in CF. The organic fertilizer and the biofertilizer both improved soil aggregate structure. Soil mass in the >0.25 mm fraction was 7.1% greater in 80%CF+OF and 8.0% greater in (60%CF+OF) than in CF. The geometric mean diameter was 9.2% greater in 80%CF+BF than in 80%CF+OF. Redundancy analysis and cluster analysis both demonstrated that soil aggregate structure and biological activities increased when organic fertilizer and biofertilizer were

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

    Science.gov (United States)

    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.

  1. Socioeconomic determinants of fertility: selected Mexican regions, 1976-1977.

    Science.gov (United States)

    Pick, J B; Butler, E W; Pavgi, S

    1988-01-01

    Cumulative fertility is analyzed for 4 regions of Mexico, based on World Fertility Survey data of 1976-77; the state of Baja California, the Northwest region, the State of Jalisco, and the Northeast region. Based on stepwise regression methodology, the study compares results for 12 subsamples of married respondents, 3 age categories by 4 regions. The dependent variables are children ever born and children ever born in the last 5 years. Migration, urban, educational, and occupational variables are included as independent variables. Regression results reveal level of education is the major, and negative, influence on fertility. Other results include specific negative effects for prior occupation, size of place of residence, and childhood place of residence. Fertility effects appear different for migration origin and destination regions, but more similar for younger ages. Effects of migration on fertility are small. Mean fertility as measured by children ever born was 4.34 for the 1976-77 World Fertility Survey samples versus 3.69 for the Mexican census of 1980. Fertility varied somewhat by region with the highest and lowest values in Jalisco and the Northeast, respectively. Expected age-related changes in fertility were noted.

  2. Census-linked Study on Ethnic Fertility Differentials in Lithuania

    Directory of Open Access Journals (Sweden)

    Aiva Jasilioniene

    2014-12-01

    Full Text Available Fertility transformations observed since the early 1990s and their determinants have been rather thoroughly investigated in Lithuania. There are fairly numerous national and international studies devoted to this topic, mainly based on survey data. However, none of these studies looks into the effect of ethnicity on fertility. It is, to a large extent, caused by limitations of sample survey data. This study demonstrates potentials of census-linked fertility data to estimate robust and nationally representative parity-specific period fertility measures by ethnicity. The findings of this first systematic study of ethnicity-specific fertility differentials in Lithuania indicate that ethnicity does matter for fertility even in such ethnically homogenous country as Lithuania. Fertility among Lithuanians is higher than in the other ethnic groups, especially among Russians. Lower fertility in the Russian ethnic group is mainly explained by differences in the risk of having the second child. Importantly, this disadvantage remains significant even after controlling for selected compositional characteristics including urban-rural place of residence and education. The approach used in this study may be applied for Latvia and Estonia, where national minorities constitute substantial shares of the entire populations and significantly contribute to overall fertility levels.

  3. Regulation of fertilization and early seed development.

    Science.gov (United States)

    Dresselhaus, Thomas; Doughty, James

    2014-04-01

    Plant reproduction meetings often deal either with pre-fertilization processes such as flowering and pollen biology or post-fertilization processes such as embryogenesis and seed development. The Biochemical Society Focused Meeting entitled 'Regulation of Fertilization and Early Seed Development' was organized to close this gap and to discuss mechanistic similarities and future research directions in the reproductive processes shortly before, during and after fertilization. As an outcome of the workshop, invited speakers and a few selected oral communication presenters contributed focused reviews and technical articles for this issue of Biochemical Society Transactions. We provide here a short overview of the contents and highlights of the various articles.

  4. How does variance in fertility change over the demographic transition?

    Science.gov (United States)

    Hruschka, Daniel J; Burger, Oskar

    2016-04-19

    Most work on the human fertility transition has focused on declines in mean fertility. However, understanding changes in the variance of reproductive outcomes can be equally important for evolutionary questions about the heritability of fertility, individual determinants of fertility and changing patterns of reproductive skew. Here, we document how variance in completed fertility among women (45-49 years) differs across 200 surveys in 72 low- to middle-income countries where fertility transitions are currently in progress at various stages. Nearly all (91%) of samples exhibit variance consistent with a Poisson process of fertility, which places systematic, and often severe, theoretical upper bounds on the proportion of variance that can be attributed to individual differences. In contrast to the pattern of total variance, these upper bounds increase from high- to mid-fertility samples, then decline again as samples move from mid to low fertility. Notably, the lowest fertility samples often deviate from a Poisson process. This suggests that as populations move to low fertility their reproduction shifts from a rate-based process to a focus on an ideal number of children. We discuss the implications of these findings for predicting completed fertility from individual-level variables. © 2016 The Author(s).

  5. Interracial-Interethnic Unions and Fertility in the United States

    Science.gov (United States)

    Fu, Vincent Kang

    2008-01-01

    How does the fertility of interracial and interethnic couples compare to the fertility of endogamous couples? If exogamous couples have transcended the boundary between them, then exogamy should not affect fertility. Alternatively, opposition to the relationship from the couple's family and friends may reduce fertility. This study uses 2000-2005…

  6. The fertilizer nitrogen problem

    Energy Technology Data Exchange (ETDEWEB)

    Olson, R A; Halstead, E H

    1974-07-01

    A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

  7. The fertilizer nitrogen problem

    International Nuclear Information System (INIS)

    Olson, R.A.; Halstead, E.H.

    1974-01-01

    A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

  8. Baby booms and busts: waves in fertility patterns

    NARCIS (Netherlands)

    Beets, G.C.N.

    2009-01-01

    Fertility curves sometimes resemble sea waves. During periods that the fertility age patterns change, according to whatever reason, 'this sea' may become very turbulent. Also other sea-like phenomena, for example tsunamis, are discernible in fertility behaviour. This article gives a short overview

  9. Some relations among cultural traditions, nuptiality and fertility.

    Science.gov (United States)

    Coale, A J

    1991-01-01

    Demographic transition is a period characterized by changes in mortality and fertility that accompany modernization and economic development. Typical features of age at first marriage among populations in different stages of demographic transition are described including the changes in age at marriage, the association between marriage age changes and fertility control, and the role of cultural and traditional behavior in influencing age at marriage and initiation of fertility control. In the Western model, there was a late age of marriage for women between 23 and 28 years old, and a high proportion of women who remain single until 50 years old (10-25%). The Eastern European model was one of moderately early marriage (mean age 19-22) and a small proportion remaining single (2-5%). The third model was Asian and African with early (mean age of 18 years) and universal marriage (1% unmarried). The reduction in number married was associated with reduced fertility. The differences between the Eastern and Western models were in household composition. In premodern societies, any fertility control present was governed by custom and limited biomedical influences such as duration of breast feeding and sexual abstention following a birth. These practices were not considered deliberate fertility control. The mean age of marriage in India was 14 years until 1941 and slowly reached 18.4 years in 1981. Fertility did not begin to decline until after 1960. Examples are given of the close association between marital fertility that is voluntary controlled and mean age at marriage. The influences of culture and traditions on the association between mean age of marriage and voluntary fertility control are shown by examples from the Soviet Union. The eastern part of the Soviet Union experienced a rise in mean age of marriage and an unsustained decline in marital fertility similar to that in China. There were also similarities in nuptiality and fertility between other areas in the Soviet

  10. Approach to modelling spatial changes of plant carbon: nitrogen ratios in southern Africa in relation to anticipated global climate change

    CSIR Research Space (South Africa)

    Kunz, RP

    1995-03-01

    Full Text Available animals and herbivorous insects. Equations relating the assimilation of total carbon and nitrogen rates to monthly air temperature, the ambient CO2 level and soil fertility were used together with detailed spatial climatic and soil databases to simulate...

  11. Can Fertilization of Soil Select Less Mutualistic Mycorrhizae?

    Science.gov (United States)

    Johnson, Nancy Collins

    1993-11-01

    It has been noted previously that nutrient-stressed plants generally release more soluble carbohydrate in root exudates and consequently support more mycorrhizae than plants supplied with ample nutrients. Fertilization may select strains of vesicular-arbuscular mycorrhizal (VAM) fungi that are inferior mutualists if the same characteristics that make a VAM fungus successful in roots with a lowered carbohydrate content also reduce the benefits that the fungus provides a host plant. This two-phase study experimentally tests the hypothesis that fertilizing low-nutrient soil selects VAM fungi that are inferior mutualists. The first phase examines the effects of chemical fertilizers on the species composition of VAM fungal communities in long-term field plots. The second phase measures the effects of VAM fungal assemblages from fertilized and unfertilized plots on big bluestem grass grown in a greenhouse. The field results indicate that 8 yr of fertilization altered the species composition of VAM fungal communities. Relative abundance of Gigaspora gigantea, Gigaspora margarita, Scutellispora calospora, and Glomus occultum decreased while Glomus intraradix increased in response to fertilization. Results from the greenhouse experiment show that big bluestem colonized with VAM fungi from fertilized soil were smaller after 1 mo and produced fewer inflorescences at 3 mo than big bluestem colonized with VAM fungi from unfertilized soil. Fungal structures within big bluestem roots suggest that VAM fungi from fertilized soil exerted a higher net carbon cost on their host than VAM fungi from unfertilized soil. VAM fungi from fertilized soil produced fewer hyphae and arbuscules (and consequently provided their host with less inorganic nutrients from the soil) and produced as many vesicles (and thus provisioned their own storage structures at the same level) as fungi from unfertilized soil. These results support the hypothesis that fertilization selects VAM fungi that are inferior

  12. Productivity of sugarcane plants of ratooning with fertilizing treatment

    Directory of Open Access Journals (Sweden)

    MUHADIONO

    2010-01-01

    Full Text Available Latief AS, Syarief R, Pramudya B, Muhadiono. 2010. Productivity of sugarcane plants of ratooning with various fertilizing treatments. Nusantara Bioscience 2: 43-47. This research aims to determine the sugarcane plants of ratooning productivity with low external input of fertilization treatment towards farmers can increase profits. The method used is the Completely Randomized Block Design (CRBD with four treatments and three repetitions (4x3. Sugarcane varieties R 579 planted in each patch experiment 5x5 m2. Dosage of fertilizer: P0 = 3.6 kg/year plot experiment was 100% dosage usage of chemical fertilizers used by farmers. Further dosages were P1 (75% = 2.7 kg/plot, P2 (50% = 1.8 kg/plot and P3 (0.25% = 0.9 kg/plot, each supplemented with fertilizer 5 mL of liquid organic/patch a year. Sugarcane crops with a variety of treatment showed no significant difference. The highest productivity was achieved at dosages of P2 (50% chemical fertilizers plus organic fertilizer is 21.67 kg per square meter. Chemical fertilizers can be saved 7 quintals per hectare a year or Rp 997,500 per year. Additional costs of liquid organic fertilizer Rp. 100,000 per hectare year and labor Rp 100,000 per hectare, so the additional advantage of saving farmers fertilizer Rp. 797,500 per year.

  13. Implementation strategy for achieving replacement level fertility.

    Science.gov (United States)

    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

  14. Fertility, Natural Growth, and Migration in the Czech Republic: an Urban–Suburban–Rural Gradient Analysis of Long-Term Trends and Recent Reversals

    Czech Academy of Sciences Publication Activity Database

    Vobecká, Jana; Piguet, V.

    2012-01-01

    Roč. 18, č. 3 (2012), s. 225-240 ISSN 1544-8444 R&D Projects: GA AV ČR IAA700280802 Institutional research plan: CEZ:AV0Z70280505 Keywords : cumulative cohort fertility * spatial population dynamics * suburbanisation Subject RIV: AO - Sociology, Demography Impact factor: 1.861, year: 2012 http://onlinelibrary.wiley.com/doi/10.1002/psp.698/full

  15. Contrasting responses of bacterial and fungal communities to aggregate-size fractions and long-term fertilizations in soils of northeastern China.

    Science.gov (United States)

    Liao, Hao; Zhang, Yuchen; Zuo, Qinyan; Du, Binbin; Chen, Wenli; Wei, Dan; Huang, Qiaoyun

    2018-04-20

    Soils, with non-uniform distribution of nutrients across different aggregate-size fractions, provide spatially heterogeneous microhabitats for microorganisms. However, very limited information is available on microbial distributions and their response to fertilizations across aggregate-size fractions in agricultural soils. Here, we examined the structures of bacterial and fungal communities across different aggregate-size fractions (2000-250 μm, 250-53 μm and fractions (>53 μm), especially 250-53 μm aggregates, which contain more soil C and N, are associated with greater microbial biomass and higher fungi/bacteria ratio. We firstly reported the fungal community composition in different aggregate-size fractions by HTS technology and found more Ascomycota but less Zygomycota in larger fractions with higher C content across all fertilization regimes. Fertilization and aggregate-size fractions significantly affect the compositions of bacterial and fungal communities although their effects are different. The bacterial community is mainly driven by fertilization, especially chemical fertilizers, and is closely related to the shifts of soil P (phosphorus). The fungal community is preferentially impacted by different aggregate-size fractions and is more associated with the changes of soil C and N. The distinct responses of microbial communities suggest different mechanisms controlling the assembly of soil bacterial and fungal communities at aggregate scale. The investigations of both bacterial and fungal communities could provide a better understanding on nutrient cycling across aggregate-size fractions. Copyright © 2018. Published by Elsevier B.V.

  16. Preservation of Fertility Potential for Gender and Sex Diverse Individuals.

    Science.gov (United States)

    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.

  17. Dynamic weighing for accurate fertilizer application and monitoring

    NARCIS (Netherlands)

    Bergeijk, van J.; Goense, D.; Willigenburg, van L.G.; Speelman, L.

    2001-01-01

    The mass flow of fertilizer spreaders must be calibrated for the different types of fertilizers used. To obtain accurate fertilizer application manual calibration of actual mass flow must be repeated frequently. Automatic calibration is possible by measurement of the actual mass flow, based on

  18. Reproductive health laws and fertility decline in Ghana.

    Science.gov (United States)

    Finlay, Jocelyn E; Fox, Ashley M

    2013-11-01

    An unresolved debate in demography concerns the causal sequence between the supply of contraception and the demand for smaller families in fertility decline. Through a mixed-methods approach, we explored the effect of a sudden increase in access to legal abortion on subsequent fertility decline when Ghana's criminal code was amended in 1985. Using Ghana Demographic and Health Surveys, we constructed a panel of women aged 15-34 years and undertook a spline regression analysis to examine the effect of legal changes in 1985 and fertility decline controlling for social determinants of fertility. In addition, we conducted 17 key informant interviews (KIIs) to understand the reasons for the legal change and competing explanations for fertility decline. Multivariate results indicated that the timing of the liberalization of the abortion law coincided with the onset of Ghana's fertility decline. The KIIs indicated that the reasons for the liberalization of reproductive health laws were in response to famine and physician advocacy. While the timing of the abortion law liberalization coincided with the fertility decline in Ghana, we are unable to decouple the effect of the legal change from the effects of a severe famine that affected the region at the same time. Further research on documented and undocumented abortion in Ghana should be conducted to validate the contribution of legal abortion to fertility decline. © 2013.

  19. Impact of Forage Fertilization with Urea and Composted Cattle Manure on Soil Fertility in Sandy Soils of South-Central Vietnam

    Directory of Open Access Journals (Sweden)

    Keenan C. McRoberts

    2016-01-01

    Full Text Available Increased production in smallholder beef systems requires improved forage management. Our objective was to evaluate the effects of composted cattle manure and mineral nitrogen (urea application on soil fertility and partial nutrient balances in plots established to Brachiaria cv. Mulato II in south-central coastal Vietnam from 2010 to 2013. A randomized complete block design was implemented on six farms (blocks, with five rates of composted cattle manure (0, 4, 8, 12, and 24 Mg DM/ha per yr and three urea rates (0, 60, and 120 kg N/ha per yr in a factorial design. Soil was analyzed before and after the experiment. Compost increased soil pH, organic matter, Ca, Mg, and Mn. The effect of compost and urea applications on postexperiment soil fertility depended on preexperiment soil fertility for K, P, S, Mg, Zn, Mn, Cu, and organic matter, suggesting that the ability to maintain soil fertility depends on the interaction between soil organic and inorganic amendments and existing soil fertility. Highest farm yields were also achieved on farms with higher preexperiment soil fertility levels. Negative partial nutrient balances for N, P, and K suggest that yields will not be sustainable over time even for the highest fertilization inputs used in this experiment.

  20. Soil fertility decline: definitions and assessment

    NARCIS (Netherlands)

    Hartemink, A.E.

    2006-01-01

    In permanent agricultural systems, soil fertility is maintained through applications of manure, other organic materials, inorganic fertilizers, lime, the inclusion of legumes in the cropping systems, or a combination of these. In many parts of the world the availability, use, and profitability of

  1. Factors Affecting Fertility Desires in the Philippines

    Directory of Open Access Journals (Sweden)

    Clarissa C. David

    2014-12-01

    Full Text Available Factors affecting fertility desires in the Philippines were examined using data from a national survey and from individual and group qualitative interviews involving 143 respondents. Fertility goals usually range from two to three children, but evidence suggests that they are dynamic and may change over a person’s lifetime. Qualitative interviews reveal that when negotiating about family size, it is the partner who wants more children that will be followed. A strong demand for gender balance among offspring creates a willingness to have more children than originally desired. Fertility goals increase over time among women. While those who start childbirth at a very young age successfully space their children, they tend to want larger families than those who start late. Initial fertility goals among women are generally low but may increase because of higher fertility desires among men, a demand for gender balance in children, and the desire for babies once their children have grown.

  2. Cross-cultural comparison of fertility specific quality of life in German, Hungarian and Jordanian couples attending a fertility center.

    Science.gov (United States)

    Sexty, Réka E; Hamadneh, Jehan; Rösner, Sabine; Strowitzki, Thomas; Ditzen, Beate; Toth, Bettina; Wischmann, Tewes

    2016-02-24

    Only a few studies have reported cross-cultural comparisons regarding psychosocial consequences of infertility. Differences between societies with different cultural backgrounds were revealed and seemed to be based on the importance of pronatalism. Our aim was to measure cross-cultural differences in fertility specific quality of life of infertile couples in Germany, Hungary and Jordan who attend a fertility center in a cross-sectional study. A cross-sectional study was conducted in one fertility clinic in Germany, in five fertility clinics in Hungary and in one fertility clinic in Jordan. Overall 750 couples (252 couples in Jordan, 246 couples in Germany and 252 couples in Hungary) attending the first medical infertility consultation were asked to fill out our questionnaire set. Fertility specific quality of life (FertiQoL) and sociodemographic differences were measured between couples from three countries. Jordanian couples had the shortest relationship (5.8 ± 4.3 yrs.), though they reported the longest duration of child wish (4.2 ± 3.6 yrs.) and fertility treatments (3.0 ± 3.3 yrs.). The proportion of high education was considerably higher in Jordanian women and men (60 % and 66 %, respectively) compared to the other two samples. First, marked cross-country differences were obtained on Emotional, Mind/Body and Relational subscales of the FertiQoL, indicating that Jordanian couples reported poorer fertility-related quality of life than Germans and Hungarians (p difference only in the Emotional domain was observed (p cultural based differences in fertility specific quality of life between the couples of the three countries. Thus, infertility counselors should pay attention to psychosocial problems rooted in individual sociocultural aspects of the infertile couple regardless of cultural stereotypes. Further studies should identify sociocultural factors within different subgroups of infertile patients instead of focusing different societies as a whole because

  3. Technology of boron-containing polyphosphate fertilizer 'Phosphobor'

    International Nuclear Information System (INIS)

    Aldabergenov, M.K.; Balakaeva, T.G.

    1995-01-01

    A technology is developed for producing 'Phosphobor' fertilizer based on the rock phosphate weal (17-18% P 2 O 5 ) with additions of boron-magnesium compound. Boron is part of polyphosphate fertilizer in the form of polymeric compounds of phosphorus and boron. Phosphorus and boron copolymers -boratophosphates - are easily formed in the process of polyphosphate fertilizers production, since borates undergo a mutual polycondensation reaction with phosphates. 8 refs., 1 fig

  4. The effects of 15N-fertilizer on the yields of wheat

    International Nuclear Information System (INIS)

    Zhou Dechao

    1985-01-01

    By using 15 N-fertilizer, the effects of increasing yield and the utilization of nitrogen of N-fertilizer applied at different periods and by different methods on wheat were studied. The results were as follows: The utilization of N-fertilizer by winter wheat is dependent on the fertilizer of soil before or after winter. Strong seedlings were obtained in the high fertility soils and the application of N-fertilizer in spring is recommended. In soils of low fertility, however, application of a part of N-fertilizer before winter is recommded in order to get strong seedlings. Application of a part of N-fertilizer as base manure for spring wheat is more advantageous. Deep application of N-fertilizer losses less NH 3 than surface broadcast does

  5. FERTILIZING INFLUENCE TOWARDS GROWTH AND FRUIT CROPS OF COCOA

    Directory of Open Access Journals (Sweden)

    Azri

    2015-07-01

    Full Text Available TRACT Fertilizers is one activities of maintenance plants that an important role to productivity plants. Without right fertilizing, cacao farms are many setbacks especially in quality of land. Land quality decline because reduction of nutrient in land, damage characteristics of biological or physical and more deplete substantially thickness of land. Nutrient reduction has occur caused by activities of harvest, washing, denitrification, and erosion that occurred in area of cacao plants roots. Damage of biological and physical of land include land aggregate damage, decreased stability of structure, decreased organic matter, and reducing amount of and activities of organisms that live in land. Efforts to increase land fertility can be with gift fertilizer. Study using a Random Group Design with 3 replication, with fertilizer treatment: P1 = Control (farmers; P2 = natural fertilizer 5 kg; P3 = natural fertilizer 5 kg+ 5 g urea + 5 g SP-36, and P4 = natural fertilizer 5 kg+ 5 g SP-36+ 5 g (KC1. Results of study showed that giving of manure and organic matter are significantly different with farmers (control, but best treatment is found on gift manure combined fertilizer anorganic (P3 provides growth and number of best fruit.

  6. Reproduction at the Margins: Migration and Legitimacy in the New Europe

    Directory of Open Access Journals (Sweden)

    2004-04-01

    Full Text Available One of the most compelling demographic questions in contemporary Europe has been whether immigrant populations will bring their youthful age pyramids to help support Europe's subfertile, aging populations. But how do immigrants envision their own reproductive life trajectories across vast, ambiguous political boundaries whose seismic shifts can threaten their security? This paper reviews some recent literature from demography, anthropology, and the media as well as several case studies to suggest that for immigrant families at the political margins of Europe, especially those from developing countries, the most pressing fertility question is not numbers of children. It is instead the legitimacy that children may provide in their families' efforts to gain work, social security, and rights to settle. This implies that the reproductive practices adopted by immigrants in Europe may derive less from traditions in their home countries than from efforts to adapt to new rules of "belonging" in Europe. Indeed, what seem very striking in the light of conspicuously low and increasingly non-marital fertility in mainstream Western Europe are the increasing demands placed on immigrants to pursue legitimacy in their reproductive lives. The paper concludes that levels of fertility among immigrants are unlikely to assimilate to the national norms until people's status becomes more secure. Finally, just as we can no longer rest on conventional notions of reproductive practices in the developing world, it is increasingly impossible to draw general conclusions about fertility in Europe without keeping the developing world in view.

  7. Third world programs confront adolescent fertility.

    Science.gov (United States)

    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.

  8. Variabilidade espacial de atributos da fertilidade de um Latossolo Vermelho Distroférrico sob Sistema Plantio Direto Spatial variability of the fertility attributes of Dystropheric Red Latosol under a notillage system

    Directory of Open Access Journals (Sweden)

    Flávio Carlos Dalchiavon

    2012-09-01

    Full Text Available O conhecimento da variabilidade espacial da fertilidade do solo é muito importante, principalmente, para a agricultura de precisão. Assim, durante o ano agrícola 2009/2010, no município de Selvíria (MS, no Cerrado Brasileiro, objetivou-se analisar a variabilidade espacial de atributos da fertilidade num Latossolo Vermelho Distroférrico sob plantio direto. Foi instalada a malha de amostragem para a coleta de solo, com 120 pontos amostrais, numa área de 3,0 ha e declive homogêneo de 0,055 m m-1. Foram determinados os teores de P disponível, de matéria orgânica, valor de pH (CaCl2, teores de K+, Ca+2, Mg+2, valores de saturação por bases e por alumínio, nas profundidades de 0-0,10 m e 0,10-0,20 m. Efetuou-se a análise descritiva clássica, com auxílio do software estatístico SAS, e em seguida foram modelados semivariogramas para todos os atributos, obtendo-se as respectivas validações cruzadas e mapas de krigagens com o GS+ 7.0. As maiores variabilidades dos atributos químicos analisadas pelo coeficiente de variação ocorreram na camada de 0,10-0,20 m de profundidade do solo. Todos os atributos químicos pesquisados apresentaram dependência espacial, sendo possível mapear a área em estudo. Por representar a continuidade espacial dos semivariogramas obtidos no presente estudo, os valores dos alcances geoestatísticos recomendados para os atributos ora pesquisados deverão estar compreendidos entre 40,2 e 113,1 metros.Knowledge of the spatial variability of soil fertility is very important, especially in precision agriculture. Thus during the 2009/2010 agricultural year, in the city of Selva (MS in the Brazilian Cerrado, the objective was to analyse the spatial variability of the fertility attributes of a Dystropheric Red Latosol under a no-tillage system. A sampling grid was installed to collect soil samples, with 120 sampling points in an area of 3.0 ha and on an even slope of 0.055 m m-1. The available phosphorus content

  9. Occurrence of priority organic pollutants in the fertilizers, China

    International Nuclear Information System (INIS)

    Mo Cehui; Cai Quanying; Li Yunhui; Zeng Qiaoyun

    2008-01-01

    The use of large quantities of chemical fertilizers is usually associated with environmental problems. A lot of work has been done on the concentrations of heavy metals and radionuclides in chemical fertilizers, but little work has focused on the occurrence of semi-volatile organic compounds (SVOCs). In this study the occurrence of 43 SVOCs listed as priority pollutants in 22 widely used-fertilizers of China was determined by gas chromatography coupled with mass spectrometry. Twenty-six SVOCs were detected with different detection frequencies and concentrations. The most abundant compounds were phthalic acid esters (PAEs; ranging from 1.17 to 2795 μg kg -1 dry weight, d.w.) and nitroaromatics (up to 9765 μg kg -1 d.w.), followed by polycyclic aromatic hydrocarbons (PAHs; -1 d.w.) and halogenated hydrocarbons ( -1 d.w.). Chlorobenzenes and haloethers occurred generally at low concentrations. There are large variations in concentrations of various compounds in different fertilizers, and the total concentrations of each class of contaminants varied widely, too. The highest levels of sum concentration for 16 PAHs, for 6 PAEs and for nitroaromatics were found in organic fertilizer containing pesticide and soil amendments. Concentrations of SVOCs in coated fertilizers (the controlled release fertilizer with coating) were considerably higher than those in the corresponding fertilizers without coating. The occurrence frequencies of SVOCs in the straight fertilizers (containing only one of the major plant nutrients) were lower than in the other fertilizers

  10. Determinants of adolescent fertility in Malawi | Palamuleni | Gender ...

    African Journals Online (AJOL)

    High adolescent fertility is recognized as a global challenge given its adverse consequences. As such understanding the factors that influence adolescent fertility is critical to addressing this challenge. This study aims at examining the causes of adolescent fertility in Malawi using the 2010 Malawi Demographic and Health ...

  11. Differences in partnership and marital status at first birth by women’s and partners’ education: Evidence from Britain 1991-2012

    OpenAIRE

    Peri Rotem, Nitzan; Scott, J

    2017-01-01

    Non-marital childbearing, especially within cohabitation, has become increasingly common in Britain as in other Western countries. Nonetheless, births outside marriage occur more frequently among the relatively disadvantaged in terms of income potential. Building upon previous research in family formation patterns, we examine differences by education and employment status in the proportion of marital and non-marital first births among British women and couples over the past two decades. In pa...

  12. Optical crop sensor for variable-rate nitrogen fertilization in corn: II - indices of fertilizer efficiency and corn yield

    Directory of Open Access Journals (Sweden)

    Jardes Bragagnolo

    2013-10-01

    Full Text Available Generally, in tropical and subtropical agroecosystems, the efficiency of nitrogen (N fertilization is low, inducing a temporal variability of crop yield, economic losses, and environmental impacts. Variable-rate N fertilization (VRF, based on optical spectrometry crop sensors, could increase the N use efficiency (NUE. The objective of this study was to evaluate the corn grain yield and N fertilization efficiency under VRF determined by an optical sensor in comparison to the traditional single-application N fertilization (TSF. With this purpose, three experiments with no-tillage corn were carried out in the 2008/09 and 2010/11 growing seasons on a Hapludox in South Brazil, in a completely randomized design, at three different sites that were analyzed separately. The following crop properties were evaluated: aboveground dry matter production and quantity of N uptake at corn flowering, grain yield, and vegetation index determined by an N-Sensor® ALS optical sensor. Across the sites, the corn N fertilizer had a positive effect on corn N uptake, resulting in increased corn dry matter and grain yield. However, N fertilization induced lower increases of corn grain yield at site 2, where there was a severe drought during the growing period. The VRF defined by the optical crop sensor increased the apparent N recovery (NRE and agronomic efficiency of N (NAE compared to the traditional fertilizer strategy. In the average of sites 1 and 3, which were not affected by drought, VRF promoted an increase of 28.0 and 41.3 % in NAE and NRE, respectively. Despite these results, no increases in corn grain yield were observed by the use of VRF compared to TSF.

  13. Meticulous Overview on the Controlled Release Fertilizers

    Directory of Open Access Journals (Sweden)

    Siafu Ibahati Sempeho

    2014-01-01

    Full Text Available Owing to the high demand for fertilizer formulations that will exhaust the possibilities of nutrient use efficiency (NUE, regulate fertilizer consumption, and lessen agrophysicochemical properties and environmental adverse effects instigated by conventional nutrient supply to crops, this review recapitulates controlled release fertilizers (CRFs as a cutting-edge and safe way to supply crops’ nutrients over the conventional ways. Essentially, CRFs entail fertilizer particles intercalated within excipients aiming at reducing the frequency of fertilizer application thereby abating potential adverse effects linked with conventional fertilizer use. Application of nanotechnology and materials engineering in agriculture particularly in the design of CRFs, the distinctions and classification of CRFs, and the economical, agronomical, and environmental aspects of CRFs has been revised putting into account the development and synthesis of CRFs, laboratory CRFs syntheses and testing, and both linear and sigmoid release features of CRF formulations. Methodical account on the mechanism of nutrient release centring on the empirical and mechanistic approaches of predicting nutrient release is given in view of selected mathematical models. Compositions and laboratory preparations of CRFs basing on in situ and graft polymerization are provided alongside the physical methods used in CRFs encapsulation, with an emphasis on the natural polymers, modified clays, and superabsorbent nanocomposite excipients.

  14. Micronutrients as Impurities of Inorganic Fertilizers Marketed in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    A.S. Modaihsh

    2000-06-01

    Full Text Available Inorganic fertilizers with major nutrients are likely to be contaminated with some micronutrients. Fertilizers, utilized in Saudi Arabia, were analyzed for their total and water-soluble content of Fe, Zn, Mn and Cu. They represented three categories namely: phosphatic, solid multiple nutrient fertilizers (SMNF and water-soluble multiple nutrient fertilizers (WSMF. Total iron content in examined fertilizers was higher in phosphatic fertilizers and lower in WSMF. Nevertheless, only a very small portion of the total iron content is likely to be available to plants. It was estimated, on the basis of total content, that almost 2 g of iron would be applied to soil for each added kg of phosphatic fertilizer. The highest total content of Zn was recorded for phosphatic fertilizers. The data suggested that less than half kg of Zn would be accumulated in soil if 500 kg of phosphatic fertilizers were applied in one year. This value however, fell dramatically, to one fourth of the value, when only the available forms of Zn were considered. Fertilizer content of manganese and copper were lower than both Fe and Zn. Micronutrient impurities present in inorganic fertilizers might not have an immediate influence on plant nutrition due to their lower solubility.

  15. Biochemical Disincentives to Fertilizing Cellulosic Ethanol Crops

    Science.gov (United States)

    Gallagher, M. E.; Hockaday, W. C.; Snapp, S.; McSwiney, C.; Baldock, J.

    2010-12-01

    Corn grain biofuel crops produce the highest yields when the cropping ecosystem is not nitrogen (N)-limited, achieved by application of fertilizer. There are environmental consequences for excessive fertilizer application to crops, including greenhouse gas emissions, hypoxic “dead zones,” and health problems from N runoff into groundwater. The increase in corn acreage in response to demand for alternative fuels (i.e. ethanol) could exacerbate these problems, and divert food supplies to fuel production. A potential substitute for grain ethanol that could reduce some of these impacts is cellulosic ethanol. Cellulosic ethanol feedstocks include grasses (switchgrass), hardwoods, and crop residues (e.g. corn stover, wheat straw). It has been assumed that these feedstocks will require similar N fertilization rates to grain biofuel crops to maximize yields, but carbohydrate yield versus N application has not previously been monitored. We report the biochemical stocks (carbohydrate, protein, and lignin in Mg ha-1) of a corn ecosystem grown under varying N levels. We measured biochemical yield in Mg ha-1 within the grain, leaf and stem, and reproductive parts of corn plants grown at seven N fertilization rates (0-202 kg N ha-1), to evaluate the quantity and quality of these feedstocks across a N fertilization gradient. The N fertilization rate study was performed at the Kellogg Biological Station-Long Term Ecological Research Site (KBS-LTER) in Michigan. Biochemical stocks were measured using 13C nuclear magnetic resonance spectroscopy (NMR), combined with a molecular mixing model (Baldock et al. 2004). Carbohydrate and lignin are the main biochemicals of interest in ethanol production since carbohydrate is the ethanol feedstock, and lignin hinders the carbohydrate to ethanol conversion process. We show that corn residue carbohydrate yields respond only weakly to N fertilization compared to grain. Grain carbohydrate yields plateau in response to fertilization at

  16. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for ...

  17. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult ...

  18. Computational identification of fertility functions of bovine Reprimo ...

    African Journals Online (AJOL)

    Improvement in fertility is possible through gene assisted selection. Cattle fertility and genes underlying it should be thoroughly studied and exploited to find solution to declining cattle fertility. Reprimo (RPRM) gene is a pleiotropic gene involved in suppression of cancer, regulation of mitotic cell cycle, cell cycle arrest and ...

  19. In-Vitro Fertilization Practice: Awareness and Perceptions Among ...

    African Journals Online (AJOL)

    5,6. 7-9. 10,11. 12-15. 16. 17. MATERIALS AND METHODS. In-Vitro Fertilization Practice: Awareness and Perceptions. Among Women Attending Fertility ..... technology. In: Kruger TF, Van der Spuy ZM,. Kempers RD, (Eds). Advance in fertility studies and reproductive medicine. Cape Town. Juta and. Co. Ltd, 2007: 234-240.

  20. Litter Quality of Populus Species as Affected by Free-Air CO2 Enrichment and N-Fertilization

    International Nuclear Information System (INIS)

    Vermue, E.; Buurman, P.; Hoosbeek, M.R.

    2010-01-01

    The effect of elevated CO 2 and nitrogen fertilization on the molecular chemistry of litter of three Populus species and associated soil organic matter (SOM) was investigated by pyrolysis-gas chromatography/mass spectrometry. The results are based on 147 quantified organic compounds in 24 litter samples. Litter of P. euramerica was clearly different from that of P. nigra and P. alba. The latter two had higher contents of proteins, polysaccharides, and cutin/cutan, while the former had higher contents of phenols and benzofurans/pyrans. The difference between replications was at least as large as the effect of treatments, so that no systematic chemical changes were attributable to CO 2 effect or N-fertilization effect. The chemistry of SOM under the various species and treatments did not show significant changes either. The low number of available replicates that is two was clearly insufficient to overcome the effect of spatial variation on litter chemistry and detect small differences in molecular litter chemistry.

  1. Litter Quality of Populus Species as Affected by Free-Air CO2 Enrichment and N-Fertilization

    Directory of Open Access Journals (Sweden)

    Esther Vermue

    2009-01-01

    Full Text Available The effect of elevated CO2 and nitrogen fertilization on the molecular chemistry of litter of three Populus species and associated soil organic matter (SOM was investigated by pyrolysis-gas chromatography/mass spectrometry. The results are based on 147 quantified organic compounds in 24 litter samples. Litter of P. euramerica was clearly different from that of P. nigra and P. alba. The latter two had higher contents of proteins, polysaccharides, and cutin/cutan, while the former had higher contents of phenols and benzofurans/pyrans. The difference between replications was at least as large as the effect of treatments, so that no systematic chemical changes were attributable to CO2 effect or N-fertilization effect. The chemistry of SOM under the various species and treatments did not show significant changes either. The low number of available replicates that is two was clearly insufficient to overcome the effect of spatial variation on litter chemistry and detect small differences in molecular litter chemistry.

  2. Female employment reduces fertility in rural Senegal.

    Science.gov (United States)

    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.

  3. Fertility effects of cancer treatment.

    Science.gov (United States)

    Marsden, Donald E; Hacker, Neville

    2003-01-01

    Cancer sufferers are a subfertile group, and most treatments have the potential to adversely affect gonadal function. As cancer treatment becomes more effective and survival rates improve there are more cancer survivors in the reproductive age group for whom parenting is an important consideration. This article outlines the effects on fertility of cancer treatments and techniques to minimise the risk of infertility. The overall prospects for younger cancer sufferers to either retain their fertility or have genetic offspring is now better than ever before, due to advances in assisted reproductive technology, the appropriate use of fertility sparing surgery and other techniques to reduce the toxicity of therapy on the reproductive organs. These advances raise new moral and ethical concerns that must be considered before advising cancer sufferers of the options for preserving reproductive capacity.

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

    Science.gov (United States)

    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 Rwanda's national fertility rate and support families to achieve their desired fertility. Strategies include policies and programs that promote delayed sexual debut via educational and economic opportunities for women, improved access to reproductive health information and services at schools and via health campaigns, and involvement of men in family planning decision making.

  5. Human rights to in vitro fertilization.

    Science.gov (United States)

    Zegers-Hochschild, Fernando; Dickens, Bernard M; Dughman-Manzur, Sandra

    2013-10-01

    The Inter-American Court of Human Rights (the Court) has ruled that the Supreme Court of Costa Rica's judgment in 2000 prohibiting in vitro fertilization (IVF) violated the human right to private and family life, the human right to found and raise a family, and the human right to non-discrimination on grounds of disability, financial means, or gender. The Court's conclusions of violations contrary to the American Convention on Human Rights followed from its ruling that, under the Convention, in vitro embryos are not "persons" and do not possess a right to life. Accordingly, the prohibition of IVF to protect embryos constituted a disproportionate and unjustifiable denial of infertile individuals' human rights. The Court distinguished fertilization from conception, since conception-unlike fertilization-depends on an embryo's implantation in a woman's body. Under human rights law, legal protection of an embryo "from conception" is inapplicable between its creation by fertilization and completion of its implantation in utero. © 2013.

  6. Evaluation of the residual effect of P fertilizer`s on plant P nutrition using isotopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Fardeau, J.C. [CEA Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Physiologie Vegetale et Ecosystemes; Kato, N. [National Inst. of Agro-Environmental Sciences, Tsukuba, Ibaraki (Japan); Zapata, F. [International Atomic Energy Agency, Seibersdorf (Austria). Laboratories

    1994-12-31

    The residual effect of P fertilizers previously applied to a soil on plant P nutrition was examined by both the isotopic dilution method (pot experiment) and isotopic exchange method (laboratory test) using {sup 32}p as a tracer. The fraction of P derived from a fertilizer in plant (%Pdff in plant) was compared with the fraction of P derived from fertilizer in soil solution (%Pdff in soil solution) which is a new laboratory index proposed by Morel and Fardeau to predict %Pdff in plant. Four soil samples of a Humic Andosol from long-term experimental plots, which received no fertilizer (A1 soil), a readily soluble fertilizer (A2 soil), the same readily soluble fertilizer (RSF) plus a fused magnesium phosphate (A3 soil), and combination of RSF with Florida phosphate rock (A4 soil), were tested. In the pot experiment, maize (Zea mays) was grown during 38 days and dry shoot weight, P uptake and specific radioactivity were measured. Dry shoot weight, P uptake and L-value were the highest in A3 soil, followed by A4, A2 and A1 soils. %Pdff in plant were 71,9%, 51,9% and 15,4% in A3, A4 and A2 soils respectively. A laboratory study using {sup 32}p isotopic exchange kinetics was carried out to examine three status parameters of soil P, intensity, quantity and capacity factors. Goof agreement was obtained between quantity factor (E{sub 1}-value), and the pot experimental data; i.e. P uptake and L-value. %Pdff in soil solution were similar to those %Pdff in plant except for A4 soil. The enhancement of P uptake by the plant from the phosphate rock obtained in A4 soil could be attributed to specific plant factors and soil moisture conditions. (authors).

  7. Efficiency of nitrogen in NP compound (Mixed) fertilizers

    International Nuclear Information System (INIS)

    Guo Ying; Peng Genyuan; Wang Fujun

    1990-01-01

    Pot experiments with spring wheat (Triticum aestivum L.) and rice (Oryza sativa L.) were designed to study the utilization rate of different forms of 15 N labelled components of fertilizers and the efficiency of N residual in soil. Results showed that: 1. Three kinds of fertilizers (nitrophosphate, urea + MAP, and urea + superphosphate) gave the same effect on the yields of wheat when they were used as a basal fertilizer. 2. The utilization rate of fertilizer nitrogen by the shoot of wheat depends on the nitrogen form rather than type and composition of fertilizer. The utilization rates are 35.0% for NH 4 + in urea + MAP; 31.4% for NH 4 + in nitrophosphate; 28.1% for urea N in urea + MAP; 24.8% for NO 3 - in nitrophosphate. Among the three forms, the NO 3 - of nitrophosphate was of the highest soil residual rate (48.9%) and the nitrogen in NH 4 H 2 PO 4 had the lowest loss (22.7%). 3. All types of tested fertilizers applied to spring wheat as basal nutrient were of equal effect on grain yield of the subsequently planted rice. 7.2%-8.9% of 15 N labelled components of fertilizers applied to spring wheat as basal nutrient were utilized by rice plants (grain + straw)

  8. Tillage, fertilization systems and chemical attributes of a Paleudult

    Directory of Open Access Journals (Sweden)

    Evelyn Penedo Dorneles

    2015-02-01

    Full Text Available Tillage and fertilization methods may affect soil fertility. With the aim of assessing changes in soil chemical properties over a period of ten years, soil samples of a Paleudult were collected over nine seasons at three layer depths (0-5, 5-10, 10-20 cm and were chemically analyzed. Grain yield and nutrient export in two summer crops, soybean (Glycine max and corn (Zea mays, in a field experiment set in Eldorado do Sul, in the state of Rio Grande do Sul, Brazil, were determined. Three soil tillage systems were evaluated, conventional (CT, reduced (RT and no-tillage (NT, combined with mineral (lime and fertilizers and organic (poultry litter fertilization. The no-tillage system stood out as compared to the others, especially in the surface layer, in terms of values of organic matter, soil pH, available phosphorus, cation exchange capacity and base saturation. Phosphorus content was higher under organic than mineral fertilization due to the criteria used for the establishment of fertilizer doses. Under organic fertilization, soil pH values were similar to those obtained in limed soil samples because of the cumulative effect of the organic fertilizer. Soybean yield was lower under NT in comparison to the RT and CT systems. Consequently, soybean grain exported a lower content of nutrients than maize grain. Maize yield was not affected by either tillage or fertilization systems.

  9. Greenhouse gas emissions from nitrogen fertilizer use in China

    International Nuclear Information System (INIS)

    Kahrl, Fredrich; Li, Yunju; Su, Yufang; Tennigkeit, Timm; Wilkes, Andreas; Xu, Jianchu

    2010-01-01

    The use of synthetic nitrogen (N) fertilizers is an important driver of energy use and greenhouse gas (GHG) emissions in China. This paper develops a GHG emission factor for synthetic N fertilizer application in China. Using this emission factor, we estimate the scale of GHG emissions from synthetic nitrogen fertilizer use in Chinese agriculture and explore the potential for GHG emission reductions from efficiency improvements in N fertilizer production and use. The paper concludes with a discussion on costs and financing for a large-scale fertilizer efficiency improvement program in China, and how a GHG mitigation framework might contribute to program design.

  10. Fertility impairment in radiotherapy

    Directory of Open Access Journals (Sweden)

    Marta Biedka

    2016-02-01

    Full Text Available Infertility as a result of antineoplastic therapy is becoming a very important issue due to the growing incidence of neoplastic diseases. Routinely applied antineoplastic treatments and the illness itself lead to fertility disorders. Therapeutic methods used in antineoplastic treatment may cause fertility impairment or sterilization due to permanent damage to reproductive cells. The risk of sterilization depends on the patient’s sex, age during therapy, type of neoplasm, radiation dose and treatment area. It is known that chemotherapy and radiotherapy can lead to fertility impairment and the combination of these two gives an additive effect. The aim of this article is to raise the issue of infertility in these patients. It is of growing importance due to the increase in the number of children and young adults who underwent radiotherapy in the past. The progress in antineoplastic therapy improves treatment results, but at the same time requires a deeper look at existential needs of the patient. Reproductive function is an integral element of self-esteem and should be taken into account during therapy planning.

  11. Lime and fertilizer recommendation system for coconut trees

    Directory of Open Access Journals (Sweden)

    Gustavo Nogueira Guedes Pereira Rosa

    2011-02-01

    Full Text Available Fertilizer recommendation to most agricultural crops is based on response curves. Such curves are constructed from field experimental data, obtained for a particular condition and may not be reliable to be applied to other regions. The aim of this study was to develop a Lime and Fertilizer Recommendation System for Coconut Crop based on the nutritional balance. The System considers the expected productivity and plant nutrient use efficiency to estimate nutrient demand, and effective rooting layer, soil nutrient availability, as well as any other nutrient input to estimate the nutrient supply. Comparing the nutrient demand with the nutrient supply the System defines the nutrient balance. If the balance for a given nutrient is negative, lime and, or, fertilization is recommended. On the other hand, if the balance is positive, no lime or fertilizer is needed. For coconut trees, the fertilization regime is divided in three stages: fertilization at the planting spot, band fertilization and fertilization at the production phase. The data set for the development of the System for coconut trees was obtained from the literature. The recommendations generated by the System were compared to those derived from recommendation tables used for coconut crop in Brazil. The main differences between the two procedures were for the P rate applied in the planting hole, which was higher in the proposed System because the tables do not pay heed to the pit volume, whereas the N and K rates were lower. The crop demand for K is very high, and the rates recommended by the System are superior to the table recommendations for the formation and initial production stage. The fertilizer recommendations by the System are higher for the phase of coconut tree growth as compared to the production phase, because greater amount of biomass is produced in the first phase.

  12. Effect of compound bio-fertilizer on fertilizer efficiency of rice and active nutrients of soil after harvesting by 15N tracing

    International Nuclear Information System (INIS)

    Lin Daiyan; Weng Boqi; Lin Yan

    2005-01-01

    The experimental study on the effects of bio-fertilizer on pot planted rice showed that bio-fertilizer could promote the nutrient supply for rice. In addition, the nutrient content in soil after harvesting was increased through the application of bio-fertilizer. 15 N tracing showed that Bacillus azotofixans in bio-fertilizer can provided 99.5 mg/ plant azote for rice, which was about 11.92% of the total azote absorption. At the same time, micro-organism could decrease the loss of the azote, thus increasing the recovery rate of azote. (authors)

  13. Radiological Evaluation of phosphate fertilizers used in Tunisia

    International Nuclear Information System (INIS)

    Jemli, Khaoula

    2010-01-01

    The need of control of natural radioactivity in the environment and the radiological impact of the use of chemical fertilizers has led us in this work to measure the natural radioactivity of the phosphate fertilizers in Tunisia. The distribution of various radionuclides during their manufacturing process of fertilizers is also part of this work.

  14. Uterine artery embolization angiography and fertility related aspects

    Directory of Open Access Journals (Sweden)

    Irina A. Horhoianu

    2016-05-01

    Full Text Available Purpose. Uterine artery embolization is a minimally invasive technique. It applies the principle of targeted anatomical structure devascularisation with utility in fibroid conservative therapy, including for future fertility preserving status. The objective of our paper represents a description and evaluation of angiography utility as a predictive method for fertility maintenance. Material and Methods. The angiography and ultrasound aspects obtained from a prospective study in which selected patients have undergone uterine artery embolization for fertility preservation are detailed. Results. The following angiography aspects have been detected: left- right shunt and utero-ovarian collaterals; these have been compared with the ultrasound aspects related to the fibroid evolution form a volumetric and Doppler ultrasound point of view. The angiographical description predicts the impact on post embolization fibroid evolution and upon fertility. An analysis is made in order to assess the way in which angiography can contribute to fertility alteration. Conclusions. The angiography aspects during embolization and the following ultrasound aspects can represent predictive factors as to fertility evolution after uterine artery embolization.

  15. Women's Fertility Status Alters Other Women's Jealousy and Mate Guarding.

    Science.gov (United States)

    Hurst, Ashalee C; Alquist, Jessica L; Puts, David A

    2017-02-01

    Across three studies, we tested the hypothesis that women exhibit greater jealousy and mate guarding toward women who are in the high (vs. low) fertility phase of their cycle. Women who imagined their partner with a woman pictured at high fertility reported more jealousy than women who imagined their partner with a woman pictured at low fertility (Studies 1 and 2). A meta-analysis across studies manipulating fertility status of the pictured woman found a significant effect of fertility status on both jealousy and mate guarding. Women with attractive partners viewed fertile-phase women as less trustworthy, which led to increased mate guarding (Study 2). In Study 3, the closer women were to peak fertility, the more instances they reported of other women acting jealously and mate guarding toward them. These studies provide evidence that women selectively exhibit jealousy and mate guarding toward women who are near peak fertility.

  16. Fertility Adaptation of Child Migrants to Canada

    Science.gov (United States)

    Adsera, Alicia; Ferrer, Ana

    2013-01-01

    This study analyzes the fertility behavior of immigrant women arriving to Canada before age 19 using the 20 per cent sample of the Canadian Census from 1991 through 2006. Findings show that fertility increases with age at immigration, and is particularly high for those immigrating in their late teens. This pattern prevails regardless of the country of origin or whether the mother tongue of the migrant is an official language in Canada or not. We do not find a ‘critical age’ at which the behavior of migrants with and without official mother tongue start to diverge by more, even though the fertility of migrants without official mother tongue is always higher on average. Formal education matters as the fertility of immigrants who arrived to Canada before adulthood and graduated from college is similar to that of their native peers regardless of their age of arrival. However, the fertility of those with less than tertiary education increasingly diverges with age at migration from similarly educated Canadians. PMID:23800074

  17. [Effects of mechanical transplanting of rice with controlled release bulk blending fertilizer on rice yield and soil fertility].

    Science.gov (United States)

    Zhang, Xuan; Ding, Jun-Shan; Liu, Yan-Ling; Gu, Yan; Han, Ke-Feng; Wu, Liang-Huan

    2014-03-01

    Abstract: A 2-year field experiment with a yellow-clay paddy soil in Zhejiang Province was conducted to study the effects of different planting measures combined with different fertilization practices on rice yield, soil nutrients, microbial biomass C and N and activities of urease, phosphatase, sucrase and hydrogen peroxidase at the maturity stage. Results showed that mechanical transplanting of rice with controlled release bulk blending (BB) fertilizer (BBMT) could achieve a significantly higher mean yield than traditional manual transplanting with traditional fertilizer (TFTM) and direct seeding with controlled release BB fertilizer (BBDS) by 16.3% and 27.0%, respectively. The yield by BBMT was similar to that by traditional manual transplanting with controlled release BB fertilizer (BBTM). Compared with TFTM, BBMT increased the contents of soil total-N, available N, available P and microbial biomass C, and the activities of urease, sucrase and hydrogen peroxidase by 21.5%, 13.6%, 41.2%, 27.1%, 50.0%, 22.5% and 46.2%, respectively. Therefore, BBMT, a simple high-efficiency rice cultivation method with use of a light-weighted mechanical transplanter, should be widely promoted and adopted.

  18. Effect of anhydrous magnesium sulphate fertilizer and cutting ...

    African Journals Online (AJOL)

    Effect of anhydrous magnesium sulphate fertilizer on Panicum maximum yield and chemical composition of the resultant herbage harvested at 3, 4 and 5 weeks of age was investigated. The treatments were labeled T1 to T6. T1 was fertilized and harvested at 3 weeks cutting interval, T2 was fertilized and harvested at 4 ...

  19. Evaluation of influence of fertilizers in radium concentration from tomato culture

    International Nuclear Information System (INIS)

    Lauria, Dejanira C.; Ribeiro, Fernando C.A.; Alleluia, Irene B.; Perez, Daniel V.

    2001-01-01

    The fertilizer contribution to radio uptake by tomato plants was assessed. Tomato and soil samples from four different plantations were analyzed: two using organic fertilizer and two using phosphate fertilizer. The Ra concentrations in eight of the most used tomato fertilizers were determined. The concentration values ranged from 14 to 221 Bq/kg of Ra-226 and from 25 to 176 Bq/kg of Ra-228. Owing to the low Ra concentration and to the used fertilizer quantities, the fertilizers would not increase significantly the Ra soil concentration. However, the highest soil to plant concentration ratios were found in the plantations using phosphate fertilizers. This outcome pointed out the higher Ra availability in the phosphate fertilizer plantations than in the organic fertilizer plantations, showing a possible positive influence of phosphate fertilizers for the tomato Ra uptake. Due to the phosphate fertilizer used, the dose could increase from 0,05 Sv/year to 0,24 Sv/year. However this increase is not significant face the ingestion average worldwide effective dose. (author)

  20. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available Sorry, you need to enable JavaScript to visit this website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ...

  1. Female employment reduces fertility in rural Senegal.

    Directory of Open Access Journals (Sweden)

    Goedele Van den Broeck

    Full Text Available 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.

  2. Perchlorate in Fertilizers

    National Research Council Canada - National Science Library

    Eldridge, J. E; Tsui, D. T; Mattie, D. R; Crown, J; Scott, R; Blackman, T

    1999-01-01

    ...) methods for perchlorate analysis in lawn and garden fertilizers. Seven government, private, and commercial laboratories participated in the analysis of 34 aqueous suspensions of the test materials, using similar ion chromatography systems...

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

    Science.gov (United States)

    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

  4. Pensions with Heterogenous Individuals and Endogenous Fertility

    OpenAIRE

    Cremer, Helmuth; Gahvari, Firouz; Pestieau, Pierre

    2004-01-01

    This paper studies the design of pension schemes in a society where fertility is endogenous and parents differ in their ability to raise children. In a world with perfect information, a pay-as-you-go social security system is characterized by equal pensions for all but different contributions which may or may not increase with the number of children. Additionally, fertility must be subsidized at the margin to correct for the externality that accompanies fertility. In a world of asymmetric inf...

  5. Relationship between Balanced Fertilization and Healthy Agricultural Products (A Review

    Directory of Open Access Journals (Sweden)

    M.J. Malakouti

    2011-01-01

    Full Text Available Based on World Health Organization (WHO report, our society’s health ranks 123 among 192 countries. Unfortunately, this ranking position is very low and its main reason is malnutrition due to imbalanced fertilization. Although more than 85% of Iranian people are not hungry, about 90% of them are suffering from cell hunger, because agricultural authorities and hence producers do not pay attention to food security. According to the latest information, about 86.5% of applied fertilizers in our country appertain to urea and triple super phosphate. In fact, this is an alarming issue in respect to the production of healthy agricultural products and it remains a threat to food security. At present, a total subsidy of more than 7,000 billion rials is paid for nitrogen (N and phosphate (P fertilizers. Whereas, it should be considered that, firstly, the efficiency of these fertilizers, due to different reasons such as mismanagement and existing subsidy level, is low and, secondly, the overuse of these fertilizers causes the accumulation of nitrate (NO3 and cadmium (Cd in agricultural products. Furthermore, according to the law of minimum, the overdosed fertilizers do not have any special positive effect on sustainable production and society’s health. Paying for such high-cost subsidy just for N and P-fertilizers has caused farmers to overuse and waste these fertilizers in the country and moreover not having any tendency to apply biologic, organic and micronutrient fertilizers. Whereas, the application of these fertilizers, beside their adaptability with the environment, has a very positive effect on the human health. Therefore, at this time scientific management of production and application of all kinds of fertilizers is inevitable. In this case, by improving the quality of all types of fertilizers, and following the principle of balanced fertilization, besides achieving the desired yield increase, the quality of agricultural products will be

  6. Aqueous and gaseous nitrogen losses induced by fertilizer application

    Energy Technology Data Exchange (ETDEWEB)

    Gu, C.; Maggi, F.; Riley, W.J.; Hornberger, G.M.; Xu, T.; Oldenburg, C.M.; Spycher, N.; Miller, N.L.; Venterea, R.T.; Steefel, C.

    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 and 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.

  7. Use of fertility drugs and risk of ovarian cancer.

    Science.gov (United States)

    Diergaarde, Brenda; Kurta, Michelle L

    2014-06-01

    The purpose of this review is to highlight recent research and insights into the relationship between fertility drug use and ovarian cancer risk. Results from two large case-control studies provided further evidence that fertility drug use does not significantly contribute to risk of ovarian cancer among the majority of women when adjusting for known confounding factors. However, questions regarding the effect on certain subgroups, including long-term fertility drug users, women who remain nulligravid after fertility treatment, women with BRCA1 or BRCA2 mutations and borderline ovarian tumours, still remain. In addition, it may currently just be too early to determine whether there is an association between fertility drug use and ovarian cancer risk given that many of the exposed women are only now beginning to reach the ovarian cancer age range. Whether use of fertility drugs increases the risk of ovarian cancer is an important question that requires further investigation, in particular given the large number of women utilizing fertility treatments. Fortunately, results from recent studies have been mainly reassuring. Large well designed studies with sufficient follow-up time are needed to further evaluate the effects of fertility treatments within subgroups defined by patient and tumour characteristics.

  8. Fertility Preservation Counseling for Pediatric and Adolescent Cancer Patients.

    Science.gov (United States)

    Campbell, Jessica E; Assanasen, Chatchawin; Robinson, Randal D; Knudtson, Jennifer F

    2016-03-01

    Fertility preservation for children and young adults with cancer is an important part of comprehensive patient care. In 2013, the American Society of Clinical Oncology (ASCO) released updated clinical practice guidelines addressing fertility preservation. This study aimed to evaluate if pediatric oncologists were performing fertility preservation counseling, if the new guidelines were being adopted, and how reproductive endocrinologists can educate this patient population and their providers. A cross-sectional study was performed from May 26, 2014, to August 26, 2014. An online survey addressing fertility preservation practice patterns was created and provided to the members of the Children's Oncology Group (COG). Thirty-five percent of the 234 respondents reported reading the new 2013 ASCO guidelines. Ninety-five percent of providers reported mentioning fertility preservation options prior to treatment, most commonly including referral to a reproductive endocrinologist (28%), and sperm banking (57%). The most commonly reported barrier to fertility preservation counseling was the cost of treatment. Fertility preservation counseling is being performed by pediatric oncology providers. Familiarity of the ASCO guidelines is limited, revealing that the established methods for fertility preservation in women--embryo and oocyte cryopreservation--may be offered less than experimental methods in this younger patient population. Such differences in apparent practice patterns highlight the need for more education for providers.

  9. Parental Infertility, Fertility Treatment, and Childhood Epilepsy

    DEFF Research Database (Denmark)

    Kettner, Laura O; Ramlau-Hansen, Cecilia Høst; Kesmodel, Ulrik S

    2016-01-01

    . RESULTS: 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......BACKGROUND: 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. METHODS: 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...

  10. Perceived partner fertility desires and influence on contraceptive use.

    Science.gov (United States)

    Gibbs, Susannah E; Moreau, Caroline

    2017-08-01

    Perceived discordance of fertility desires may be more common among couples with certain sociodemographic characteristics and may lead to lower contraceptive use. Using nationally representative data from adults ages 15-49 in France in 2010, we analysed associations between sociodemographic characteristics, perceived discordance of fertility desires and contraceptive use with design-based logistic regression. Only 8% of participants perceived discordant fertility desires while 92% perceived concordance with partner fertility desire. Discordance varied by age and relationship duration and by the presence of children from previous relationships. Perceived discordance was not associated with use of a hormonal or highly effective method. Beyond own intentions, perception of a partner's fertility desires was associated with using a highly effective method among participants using any method. Engaging men and couples in family planning programmes may be important for achieving both partners' desired fertility goals.

  11. Is Buddhism the low fertility religion of Asia?

    Directory of Open Access Journals (Sweden)

    Vegard Skirbekk

    2015-01-01

    Full Text Available Background: The influence of religion on demographic behaviors has been extensively studied mainly for Abrahamic religions. Although Buddhism is the world's fourth largest religion and is dominant in several Asian nations experiencing very low fertility, the impact of Buddhism on childbearing has received comparatively little research attention. Objective: This paper draws upon a variety of data sources in different countries in Asia in order to test our hypothesis that Buddhism is related to low fertility. Methods: Religious differentials in terms of period fertility in three nations (India, Cambodia and Nepal and cohort fertility in three case studies (Mongolia, Thailand and Japan are analyzed. The analyses are divided into two parts: descriptive and multivariate analyses. Results: Our results suggest that Buddhist affiliation tends to be negatively or not associated with childbearing outcomes, controlling for education, region of residence, age and marital status. Although the results vary between the highly diverse contextual and institutional settings investigated, we find evidence that Buddhist affiliation or devotion is not related to elevated fertility across these very different cultural settings. Conclusions: Across the highly diverse cultural and developmental contexts under which the different strains of Buddhism dominate, the effect of Buddhism is consistently negatively or insignificantly related to fertility. These findings stand in contrast to studies of Abrahamic religions that tend to identify a positive link between religiosity and fertility.

  12. Effects of mineral and organic fertilizers on crop productivity and ...

    African Journals Online (AJOL)

    Other two fields grown with the same crops without fertilizer application served as control treatment. In addition, a greenhouse experiment was run to ... It was concluded that biophysical factors (field location and initial soil fertility status) greatly influenced crop yield and fertilizer. Keywords: Bean, maize, fertilizer response, ...

  13. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu Reprotopia_ ... Northwestern University © 2015 Northwestern University Contact Northwestern ... Information University Policies Oncofertility Consortium ...

  14. Modelling Spatial Interactions in the Arbuscular Mycorrhizal Symbiosis using the Calculus of Wrapped Compartments

    Directory of Open Access Journals (Sweden)

    Cristina Calcagno

    2011-09-01

    Full Text Available Arbuscular mycorrhiza (AM is the most wide-spread plant-fungus symbiosis on earth. Investigating this kind of symbiosis is considered one of the most promising ways to develop methods to nurture plants in more natural manners, avoiding the complex chemical productions used nowadays to produce artificial fertilizers. In previous work we used the Calculus of Wrapped Compartments (CWC to investigate different phases of the AM symbiosis. In this paper, we continue this line of research by modelling the colonisation of the plant root cells by the fungal hyphae spreading in the soil. This study requires the description of some spatial interaction. Although CWC has no explicit feature modelling a spatial geometry, the compartment labelling feature can be effectively exploited to define a discrete surface topology outlining the relevant sectors which determine the spatial properties of the system under consideration. Different situations and interesting spatial properties can be modelled and analysed in such a lightweight framework (which has not an explicit notion of geometry with coordinates and spatial metrics, thus exploiting the existing CWC simulation tool.

  15. Correlates of biological soil crust abundance across a continuum of spatial scales: Support for a hierarchical conceptual model

    Science.gov (United States)

    Bowker, M.A.; Belnap, J.; Davidson, D.W.; Goldstein, H.

    2006-01-01

    1. Desertification negatively impacts a large proportion of the global human population and > 30% of the terrestrial land surface. Better methods are needed to detect areas that are at risk of desertification and to ameliorate desertified areas. Biological soil crusts are an important soil lichen-moss-microbial community that can be used toward these goals, as (i) bioindicators of desertification damage and (ii) promoters of soil stability and fertility. 2. We identified environmental factors that correlate with soil crust occurrence on the landscape and might be manipulated to assist recovery of soil crusts in degraded areas. We conducted three studies on the Colorado Plateau, USA, to investigate the hypotheses that soil fertility [particularly phosphorus (P), manganese (Mn) and zinc (Zn)] and/or moisture limit soil crust lichens and mosses at four spatial scales. 3. In support of the soil fertility hypothesis, we found that lichen-moss crusts were positively correlated with several nutrients [Mn, Zn, potassium (K) and magnesium (Mg) were most consistent] at three of four spatial scales ranging from 3.5 cm2 in area to c. 800 km2. In contrast, P was negatively correlated with lichen-moss crusts at three scales. 4. Community composition varied with micro-aspect on ridges in the soil crust. Three micro-aspects [north-north-west (NNW), east-north-east (ENE) and TOP] supported greater lichen and moss cover than the warmer, windward and more xeric micro-aspects [west-south-west (WSW) and south-south-east (SSE)]. This pattern was poorly related to soil fertility; rather, it was consistent with the moisture limitation hypothesis. 5. Synthesis and application. Use of crusts as desertification bioindicators requires knowledge of a site's potential for crust cover in the absence of desertification. We present a multi-scale model of crust potential as a function of site properties. Future quantitative studies can use this model to guide sampling efforts. Also, our results

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  18. EFFECT OF SOIL SULFUR FERTILIZER AND SOME FOLIAR FERTILIZERS ON GROWTH AND YIELD OF BROCCOLI IN SALINE SOIL

    Directory of Open Access Journals (Sweden)

    Ali Husain JASIM

    2015-12-01

    Full Text Available Factorial experiment was conducted in the open fields of Agricultural College, Al-Qasim Green University during the agricultural seasons of 2013/2014 and 2014/2015 to study the effect of adding two levels of agricultural sulfur (control and add 100 kg.ha-1 and four levels of nutrient spray (without spray, high-potash fertilizer, high-phosphorus fertilizer and humic acid on growth and yield of broccoli under drip irrigation and polyethylene soil mulching in saline soil (9.6 dS.m-1. Randomized complete block design with three replicates was used. The results showed that agricultural sulfur led to increase number of leaves, leaf area, leaves chlorophyll content, diameter and weight of flower head compared to control. Spraying foliar fertilizer and its interaction with sulfur fertilizer also led to increase all of parameters above (except leaves chlorophyll content significantly compared to control treatment.

  19. Total fertilization failure and idiopathic subfertility

    Directory of Open Access Journals (Sweden)

    Goverde Angelique J

    2009-01-01

    Full Text Available Abstract Background To gain more insight in whether failure of intrauterine insemination (IUI treatment in patients with idiopathic subfertility could be related to diminished fertilization, the aim of this study is to compare the fertilization of an initial IVF procedure after six cycles of IUI and the fertilization of an initial IVF procedure without preceding IUI cycles in couples with idiopathic subfertility. Methods We performed a complimentary analysis of a randomized controlled trial, in which the number of total fertilization failure (TFF in the first IVF procedure after unsuccessful IUI was compared to those of IVF without preceding IUI in patients with idiopathic subfertility. These patients participated in a previous study that assessed the cost effectiveness of IUI versus IVF in idiopathic subfertility and were randomized to either IUI or IVF treatment. Results 45 patients underwent IVF after 6 cycles of unsuccessful IUI and 58 patients underwent IVF immediately without preceding IUI. In 7 patients the IVF treatment was cancelled before ovum pick. In the IVF after unsuccessful IUI group TFF was seen in 2 of the 39 patients (5% versus 7 of the 56 patients (13% in the immediate IVF group. After correction for confounding factors the TFF rate was not significantly different between the two groups (p = 0.08, OR 7.4; 95% CI: 0.5–14.9. Conclusion Our data showed that TFF and the fertilization rate in the first IVF treatment were not significantly different between couples with idiopathic subfertility undergoing IVF after failure of IUI versus those couples undergoing IVF immediately without prior IUI treatment. Apparently, impaired fertilization does not play a significant role in the success rate of IUI in patients with idiopathic subfertility.

  20. Effect of Banana Stalk Organic Fertilizer on the Growth of Chinese Cabbage

    Institute of Scientific and Technical Information of China (English)

    Zheli; DING; Lina; HAN; Zhiqiang; JIN; Bizun; WANG; Huicai; ZENG; Wei; ZHENG; Yingdui; HE; Xiaoping; ZANG

    2016-01-01

    In order to solve the problem of waste disposal after banana harvest,we use banana stalk to produce banana stalk organic fertilizer,through a plot experiment. We compare the influence of normal organic fertilizer( Wanlubao) and banana stalk organic fertilizer as base fertilizers on Chinese cabbage growth,and evaluate the economic benefits of banana stalk organic fertilizer. The results show that organic fertilizer has little effect on water content and nutrient content of Chinese cabbage,but has significant effect on plant height and leaf width. Using organic fertilizer can increase the production of Chinese cabbage by 22. 50%- 43. 10%. With 6750 kg / ha normal organic fertilizer,Chinese cabbage gets the highest yield,which reaches 30135 kg / ha,followed by the treatment of 6750 kg / ha stalk organic fertilizer. At farmers’ conventional fertilization level( 4500 kg / ha),stalk organic fertilizer can increase the yield by more than 3. 50% in comparison with the normal organic fertilizer,and the economic benefit increases by 1800 yuan / ha. As a kind of banana waste cycling product,banana stalk organic fertilizer is of low cost and good effect,and can be used instead of normal organic fertilizer.

  1. On the pace of fertility decline in sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    David Shapiro

    2017-10-01

    Full Text Available Background: This descriptive finding examines the comparative pace of fertility decline in sub-Saharan Africa, relative to Asia, Latin America and the Caribbean, and Northern Africa. Objective: We seek to determine if fertility decline has been slower in sub-Saharan Africa than elsewhere in the developing world. Methods: United Nations 2017 estimates of national fertility are used in assessing the comparative pace of fertility decline, and the four regions are compared in terms of how far they are into their fertility transition. Results: The data shows clearly that fertility decline in sub-Saharan Africa, still at a comparatively early stage, has been considerably slower than the earlier declines in Asia, Latin America and the Caribbean, and Northern Africa at comparable stages of the transition, and displays less within-region heterogeneity than the transitions in these other regions. Conclusions: The slower pace of fertility decline in sub-Saharan Africa, in conjunction with the high current fertility levels in the region, means that in the absence of policies seeking to accelerate fertility decline, sub-Saharan Africa will continue to experience rapid population growth that in turn will constrain its development. Contribution: Presentation of data in a novel way (Figures 2‒4, and associated calculations unambiguously demonstrates the slow pace of fertility decline in sub-Saharan Africa compared with other regions of the world.

  2. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Cancer Ask Your Doctor Information for Patients Many adult survivors of childhood cancer feel fertility preservation and ... Fertility preservation and adolescent cancer patients: lessons from adult survivors of childhood cancer and their parents. Cancer ...

  3. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... fertility preservation and the ability to have a future family are important. Understanding there may be fertility ... specialist in a timely manner can improve their future quality of life. Introduction You may not be ...

  4. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... fertility preservation center closest to you Visit the Pediatric Oncofertility Research Foundation Visit the Patient Navigator Website ... Ginsberg JP. New advances in fertility preservation for pediatric cancer patients. Curr Opin Pediatr. 2010;23:9- ...

  5. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... fertility preservation is important. These key points can help start the conversation: Cancer and cancer treatment may ... several resources listed on the reverse that can help you locate a fertility preservation specialist to discuss ...

  6. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... health. You may feel uncomfortable discussing issues of reproduction with your child. Ask Your Doctor Discussing fertility ... American Society for Reproductive Medicine. Fertility preservation and reproduction in patients facing gonadotoxic therapies: a committee opinion. ...

  7. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Fertil Steril. 2013; 100:1224-31. Chow EJ, et al. Pregnancy after chemotherapy in male and female ... Cancer . Urology. 2016;91:190-6. Loren AW, et al. Fertility preservation for patients with cancer: American ...

  8. Fertility preservation after chemotherapy for Hodgkin lymphoma

    NARCIS (Netherlands)

    van der Kaaij, Marleen A. E.; van Echten-Arends, Jannie; Simons, Arnold H. M.; Kluin-Nelemans, Hanneke C.

    2010-01-01

    Treatment for Hodgkin lymphoma can negatively affect fertility. This review summarizes data on fertility after chemotherapy in adult patients. Alkylating chemotherapy, especially if containing procarbazine and/or cyclophosphamide, is most harmful to gonadal functioning. Alkylating regimens cause

  9. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... be fertility preservation options available and having your child see a reproductive specialist in a timely manner ... there are options for preserving fertility in your child diagnosed with cancer. You may be focused on ...

  10. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... JP, Kolon TF. Fertility Preservation in Children and Adolescents With Cancer . Urology. 2016;91:190-6. Loren ... 10. Nieman CL, et al. Fertility preservation and adolescent cancer patients: lessons from adult survivors of childhood ...

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

    Science.gov (United States)

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

    2016-01-01

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

  12. Fertility behavior in developing economies: an investment approach.

    Science.gov (United States)

    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.

  13. Parental knowledge of fertility in male childhood cancer survivors

    NARCIS (Netherlands)

    van den Berg, Henk; Langeveld, Nelia E.

    2008-01-01

    BACKGROUND: In childhood, cancer survivors fertility is a major point of concern. In boys, only semen analysis and impregnation confirm fertility. Since parents constitute a major source of information for children, we investigated recall and assumptions on their child's fertility. PROCEDURE: One

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

    Science.gov (United States)

    Zavala De Cosio, M E

    1993-01-01

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

  15. Quality control analysis of imported fertilizers used in Ghana

    International Nuclear Information System (INIS)

    Enti-Brown, S.

    2010-01-01

    Twenty three (23) imported fertilizer samples of 5 fertilizer types have been analysed to determine their quality. The main objective of this research was to validate specifications indicated by manufacturers' on their fertilizer products. To achieve this objective, the fertilizer samples were analysed using five analytical techniques (INAA, AAS, flame photometer, kjeldahl method and UV-visible spectroscopy) to determine the concentrations of macronutrients (N, P, K, Mg, Ca and S), micronutrients (Cu, Na, Fe, Mn, Mo and Zn) and heavy metals (As, Cd, Co, Hg and Pd) in the fertilizer samples. Results obtained from analysis were compared with certified values obtained from the companies and with standard values obtained from MOFA to establish whether the imported fertilizers met standards. Two reference materials (IAEA Soil-7 and SRM 1646a Estuarine Sediment) were used to validate the quantitative methods employed in the INAA and AAS techniques. Good agreements (98%) were obtained between the measured and verified concentrations for most of the elements. Analytical results revealed that the concentrations of the primary macronutrients (N, P and K) claimed by the manufacturers were valid. In contrast, manufacturers' claims for micronutrient concentrations did not agree with analytical results. The concentrations recorded were far below the minimum plant nutrient guarantees. For instance, the highest values recorded for Cu and Zn were 0.0265% and 0.00305% respectively, whiles the minimum guaranteed values were set at 0.05%. Heavy metal levels recorded in the fertilizers were insignificant and therefore do not present possible contamination problems during fertilizer application. In conclusion, not all the nutrient requirements expected of imported fertilizers were met. There is therefore the need for a good quality control system to monitor the chemical compositions of fertilizers imported into Ghana (au).

  16. Bio-slurry as fertilizer : is bio-slurry from household digesters a better fertilizer than manure? : a literature review

    NARCIS (Netherlands)

    Bonten, L.T.C.; Zwart, K.B.; Rietra, R.P.J.J.; Postma, R.; Haas, de M.J.G.; Nysingh, S.L.

    2014-01-01

    In many developing countries manure is anaerobically digested to produce biogas. The residue of manure digestion, bio-slurry, can be used as fertilizer for crop production and aquaculture. This study compared bio-slurry and manure as fertilizers. Nutrients in bio-slurry, especially nitrogen, are

  17. Fertility in patients treated for testicular cancer.

    Science.gov (United States)

    Matos, Erika; Skrbinc, Breda; Zakotnik, Branko

    2010-09-01

    Testicular cancer affects men mostly in their reproductive age with a cure rate over 90% and fertility is one of the main concerns of survivors. To further elucidate the question of fertility after treatment for testicular cancer, we performed a survey in patients treated in our institution. We sent a questionnaire to patients treated for testicular cancer at our institute from 1976 to 2002 (n = 490) of whom 297 (60.6%) responded. We considered the patients to have conserved fertility if they had children after treatment without assisted reproductive technologies. Before treatment 119/297 (40.1%) of patients and after treatment 150/297 (50.5%) of patients tried to have children (p = 0.019). Of 119 patients who tried to have children before treatment for testicular cancer 98 (82.4%) succeeded and 74/150 (49.3%) were successful after treatment (p years. The post-treatment fatherhood in patients treated with surgery only (orchidectomy +/- retroperitoneal lymphnode dissection-RPLND) was 59%, in those with additional radiotherapy 68%, and chemotherapy 50% (p = 0.233). Fertility rate in patients where a non nerve sparing RPLND was performed was only 37%, 62% in patients with nerve sapring RPLND, and 77% in patients where RPLND was not performed (p Fertility rate after treatment for testicular cancer is reduced. From our data, the most important treatment modality that influences fertility is non nerve sparing RPLND that should be avoided whenever possible in order improve the quality of life our patients.

  18. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... available and having your child see a reproductive specialist in a timely manner can improve their future ... Can you refer us to a fertility preservation specialist to discuss my child’s options further? Fertility Preservation - ...

  19. Fertility preservation: a challenge for IVF-clinics

    NARCIS (Netherlands)

    Dahhan, Taghride; Mol, Femke; Kenter, Gemma G.; Balkenende, Eva M. E.; de Melker, Annemieke A.; van der Veen, Fulco; Dancet, Eline A. F.; Goddijn, Mariëtte

    2015-01-01

    Acute fertility preservation for women is an interdisciplinary treatment that requires adequate information provision and early referral. This quality management project aimed to improve fertility preservation care by using a practical tool: Strengths, Weaknesses, Opportunities and Threats (SWOT)

  20. The Effects of Biological Fertilizers, Chemical Fertilizers and Manure Application on Some Qualitative Characteristics of Vicia villosa Roth Forage under Greenhouse Condition

    Directory of Open Access Journals (Sweden)

    R Kamaei

    2017-03-01

    Full Text Available Introduction Fertilizer management plays an important role in successful crop production. The biological fertilizers have been suggested not only to elimination or significant reduction of chemical fertilizer dependency but also increase of soil fertility and improvement of crop yield and quality. Materials and Methods This experiment was conducted in a completely randomized design with three replications at the Research Greenhouse of Ferdowsi University of Mashhad. The experimental treatments included 1- mycorrhizae arbuscular (Glomus mosseae, 2- mycorrhizae arbuscular (Glomus mosseae + vermicompost (M+V, 3- mycorrhizae + nitroxein (included bacteria Azospirillum sp. and Azotobacter sp. (M+N, 4- mycorrhizae arbuscular + Rhizobium (R. legominuzarum (M+R, 5-mycorrhizae arbuscular + NPK Chemical fertilizer (40-40-20 (M+NPK and 6- Control (without fertilizer, C. In bio-fertilizer treatments, seeds were inoculated by mycorrhizae and Rhizobium immediately before planting, according the standard conditions and company recommendations. Chemical fertilizer and vermicompost were applied directly into the soil. The first irrigation was done immediately after planting and an additional irrigation was also done 4 days after planting to improve the seedling emergence. Subsequent irrigations were conducted at 10-days interval. Forage samples were collected at stage of 10% open bud. The samples were oven-dried in 70°C for 48 h and then weighed before being ground to pass through a 1-mm sieve. Both chemical analysis and in vitro digestibility assessments were performed in triplicate. Crud protein (CP, Ash, neutral detergent fiber (NDF and acid detergent fiber (ADF content of forages were measured by standard methods. An in vitro gas production method was conducted to determine the dry matter (DM and organic matter (OM digestibility. All data were subjected to ANOVA using the GLM procedure of SAS (SAS 9.1 and means were compared by using LSD-test at 5

  1. Using fertile couples as embryo donors: An ethical dilemma.

    Science.gov (United States)

    Alizadeh, Leila; Omani Samani, Reza

    2014-03-01

    The use of donated embryos has offered hope for infertile couples who have no other means to have children. In Iran, fertility centers use fertile couples as embryo donors. In this paper, the advantages and disadvantages of this procedure will be discussed. We conclude that embryo-donation should be performed with frozen embryos thus preventing healthy donors from being harmed by fertility drugs. There must be guidelines for choosing the appropriate donor families. In countries where commercial egg donation is acceptable, fertile couples can be procured as embryo donors thus fulfilling the possible shortage of good quality embryos. Using frozen embryos seems to have less ethical, religious and legal problems when compared to the use of fertile embryo donors.

  2. Fertilization failure after IVF in 304 couples

    DEFF Research Database (Denmark)

    Krog, Maria; Prior, Maria; Carlsen, Elisabeth

    2015-01-01

    OBJECTIVES: To identify predictors of total fertilization failure (TFF) and thereby optimize the primary allocation of patients with no well-defined male factor to either IVF or intracytoplasmatic sperm injection (ICSI). Further, to evaluate the long-term fertility prognosis of couples experiencing...... TFF. STUDY DESIGN: A retrospective case-control study including 304 couples with TFF and 304 controls with fertilization after IVF during a 10-year period from year 2000-2010. The controls were the patients with minimum one fertilized oocyte just prior to the cases. Multiple logistic regression...... analysis was used to evaluate the predictors of TFF. RESULTS: The multiple regression analysis identified the following independent predictors of TFF: female smoking, adjusted odds ratio (AOR) 1.7 (95% CI 1.1-2.3), non-tubal factor AOR 2.2 (95% CI 1.5-3.4), progressive motile spermatozoa after preparation...

  3. Production efficiency and economic potential of different soil fertility ...

    African Journals Online (AJOL)

    This paper provides the economic evaluation of different soil fertility replenishing technologies (use of inorganic fertilizers, organic manure, and rhizobium inoculant) that were tested during field studies and recommended to groundnut farmers. Data on soil fertility technologies used by households, groundnut yields, and ...

  4. Fertility patterns according to occupational grouping in Norway, 1989.

    Science.gov (United States)

    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.

  5. Fertility after uterine artery embolization: a review.

    Science.gov (United States)

    McLucas, Bruce; Voorhees, William D; Elliott, Stephanie

    2016-01-01

    Uterine artery embolization (UAE) research has largely been focused on women over 40 years, yet women of reproductive age undergo UAE without any increased morbidity. Some physicians refrain from recommending UAE to women in this age group because of some research findings showing a negative effect on fertility. This review presents a comprehensive discussion of the fertility potential of women undergoing UAE, in terms of pregnancy rates and complications as well as ovarian function and reserve. Findings indicate many benefits for women desiring fertility who undergo UAE over traditional myomectomy.

  6. Global radiological impact of the phosphate fertilizers

    International Nuclear Information System (INIS)

    Morales, Rudnei Karam; Alves, Rex Nazare

    1996-01-01

    About ninety percent of the products obtained in the phosphate industry are directly used in agriculture as fertilizers. The uranium, thorium and radium content in phosphate fertilizers pollute the soil, water and air, creating risks due to associated natural radiation. This work shows the concentration of radionuclides present in various products of the national and American phosphate fertilizers industry, and compared them with worldwide mean values. The radiological impact of the products on the environment is evaluated and suggestions are presented in order to minimize the risks due to radioactivity. (author)

  7. Effect of long-term fertilization with different norms and rates of nutrients on slightly lashed chernozem fertility

    International Nuclear Information System (INIS)

    Nankova, M.; Kirchev, C.; Penchev, E.

    1999-01-01

    As a result from a 30-year fertilization with nitrogen, phosphorus and potassium applied with different norms and rates, the nutrition regime of slightly leached chernozems was considerably altered. A significant increase of mineral nitrogen, especially of its nitrate form, was observed down the profile (140-200 cm) when applying nitrogen norms of 120 and 180 kg/ha. A high correlation between yield and nitrate nitrogen content was registered under these conditions. During the period of fertilization mentioned above, phosphorus available in soil changed from low to moderate to good and very good depending to the phosphorus fertilization norm. A considerable enrichment of the root-deep layer with available phosphorus was established. A similar tendency was registered for water-soluble and available potassium content in the surface layer in accordance with the potassium dressing. The correlation and path-coefficients calculated for the period of study show a strong relation between yield and the autumn-winter moisture reserve, rainfalls in May and in April-June; these are considered to guarantee the efficiency of mineral fertilization on yield. Refs. 4 (author)

  8. URBANIZATION AND FERTILITY RATES IN ETHIOPIA1

    African Journals Online (AJOL)

    Eyerusalem

    Survey (2010) data suggest that Ethiopia not only has one of the largest fertility rates .... Asian countries where the rural-urban fertility differentials were smaller and more ...... Sibanda, A., Z. Woubalem, D. P. Hogan, and D. P. Lindstrom. 2003.

  9. Approximation to a model of sustainable fertilization in coffee

    International Nuclear Information System (INIS)

    Martinez, Francisco J

    1999-01-01

    In the actuality famous investigators of the agriculture think that the non-equilibrium and inconvenient inherent the chemical fertilizers are the result of the disorder produced by the high entropy of these fertilizers. In spite of that, much investigation's works increment the result without to decrease the chemical fertilizer doses in crops. The present work continues an investigation begun in 1994 in la Union town Department of Narino Colombia, about an organic fertilization alternative system and improvement of soils of coffee, with the purpose to find low doses of chemical fertilizers in combination with organic manures able to compete with the chemical conventional system. In the experiment found that low-middle doses of coffee pulp and production's fertilizers correspondent to 3 kg/coffee pulp/small boxes and 35 g/17-6-18-2/plant, produced 68 % more than the full doses of the module 2 of Cenicafe. The before result indicates that it's possible to decrease costs, to improve the quality and to increase significantly the coffee production, inclusive it can improve the environmental supply or history production, without high doses of chemical fertilizer

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

    Science.gov (United States)

    Garenne, Michel; Zwang, Julien

    2006-03-01

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

  11. EFFECT OF ORGANIC AND CHEMICAL SOIL FERTILIZERS AND THEIR INTERACTIONS WITH FOLIAR FERTILIZER ON SOME VEGETATIVE GROWTH OF FENUGREEK

    Directory of Open Access Journals (Sweden)

    Ali H. JASIM

    2016-12-01

    Full Text Available The experiment was conducted on the extension experiments farm in Babylon during the growing season 2013 - 2014 to study the effect of 5 soil fertilization treatments [control, 200 kg.ha-1 of NPK (18-18-0 , 4 and 8 t.ha-1 of compost of poultry], and its interaction with 4 treatments of foliar fertilizers [control, spray urea 1 g / liter, spraying humic acid 2 ml.l-1 and spray polimet 2 ml.l-1] on growth and yield of fenugreek. Randomized complete block design (RCBD with three replications was used. Seeds are sown on lines (30 cm apart in 21.10.2013 and the experimental unit contained 6 lines. After a week of germination the seedlings were thinned to 10 cm apart. Soil fertilizers were added as side dressing and the foliar fertilizers were added twice in 15/1 and 01/02/2014. The results showed that chemical fertilizer was superior significantly compared to other treatment in plant height, number of leaves, leaf area and wet and dry weight, while poultry (8 t.ha-1 was superior compared to control in branches number and wet weight. Urea spray was superior in plant height, leaves no. and soft weight. Polimet spray was superior compared to control in branches.plant-1. The interaction between the soil and spraying fertilizers had a significant effect in increasing plant height, branches no., leaves no., leaf area and wet and dry weight.

  12. ROMANIAN FAMILY BETWEEN TRADITIONS AND MODERNISM

    Directory of Open Access Journals (Sweden)

    Raluca MARDARE

    2015-06-01

    Full Text Available Families and living arrangements have changed dramatically since the 1960s in the majority of European countries. Family life and the meaning of family have undergone a profound change. Relationships between partners or spouses, but also the relationships between parents and their children, have moved away from the realm of normative control and institutional canons, into the ideal of reflexive ‘pure relationships’ based on mutual consent and the recognition of individual autonomy. Following the collapse of communism, Romania has experienced dramatic changes in family formation. Common patterns include delays and/or declines in marriage and fertility, increasing rates of cohabitation and non-marital childbearing, rising rates of divorce. This paper aims to document the main stages of the evolution of marital behaviours in Romania from the traditional family of the 19th century to present days.

  13. Life cycle assessment (LCA) of different fertilizer product types

    NARCIS (Netherlands)

    Hasler, K.; Broering, S.; Omta, S.W.F.; Olfs, H.W.

    2015-01-01

    Appropriate use of fertilizer in crop production to limit the environmental impact is essential for sustainable agriculture. While much is known about the environmental impact of fertilizer production only a limited amount of data is available covering the whole fertilizer supply chain. Up to now no

  14. Influence on the long-term fertilizing on radioactivity soils

    International Nuclear Information System (INIS)

    Grubisic, M.; Stevanovic, D.; Stojanovic, M.; Vuletic, V.; Pantelic, G.

    2007-01-01

    Researching in this work need to give the answer in which degree application the mineral fertilizers, especially phosphate, contribute to the contamination of a soil because of long-term continually fertilizing (35 years) and differences of adopting from the corn culture and wheat nursing in monocultures. Like control, it is made measuring activity of radionuclides of a soil on experimental variety where wasn't fertilizing during the making the experiment, separately for both cultures. Based on that it is given accent only on chronic contamination of a soil by radionuclides by application mineral fertilizers at once and transport in the system of soil of different biocenoses. Based on measuring activity 40K, 137Cs, 238U, 235U, 226Ra, 232Th, 212Pb it is fortified differences in concentration of the activity of radionuclides of uranium row between the samples of smonica, fertilized and non-fertilized in the longer period. (author) [sr

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

    Directory of Open Access Journals (Sweden)

    Ondřej Šimpach

    2015-03-01

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

  16. A GIS policy approach for assessing the effect of fertilizers on the quality of drinking and irrigation water and wellhead protection zones (Crete, Greece).

    Science.gov (United States)

    Kourgialas, Nektarios N; Karatzas, George P; Koubouris, Georgios C

    2017-03-15

    Fertilizers have undoubtedly contributed to the significant increase in yields worldwide and therefore to the considerable improvement of quality of life of man and animals. Today, attention is focussed on the risks imposed by agricultural fertilizers. These effects include the dissolution and transport of excess quantities of fertilizer major- and trace-elements to the groundwater that deteriorate the quality of drinking and irrigation water. In this study, a map for the Fertilizer Water Pollution Index (FWPI) was generated for assessing the impact of agricultural fertilizers on drinking and irrigation water quality. The proposed methodology was applied to one of the most intensively cultivated with tree crops area in Crete (Greece) where potential pollutant loads are derived exclusively from agricultural activities and groundwater is the main water source. In this region of 215 km 2 , groundwater sampling data from 235 wells were collected over a 15-year time period and analyzed for the presence of anionic (ΝΟ -3 , PO -3 4 ) and cationic (K +1 , Fe +2 , Mn +2 , Zn +2 , Cu +2 , B +3 ) fertilizer trace elements. These chemicals are the components of the primary fertilizers used in local tree crop production. Eight factors/maps were considered in order to estimate the spatial distribution of groundwater contamination for each fertilizer element. The eight factors combined were used to generate the Fertilizer Water Pollution Index (FWPI) map indicating the areas with drinking/irrigation water pollution due to the high groundwater contamination caused by excessive fertilizer use. Moreover, by taking into consideration the groundwater flow direction and seepage velocity, the pathway through which groundwater supply become polluted can be predicted. The groundwater quality results show that a small part of the study area, about 8 km 2 (3.72%), is polluted or moderately polluted by the excessive use of fertilizers. Considering that in this area drinking water sources

  17. Fate of Zinc Oxide Nanoparticles Coated onto Macronutrient Fertilizers in an Alkaline Calcareous Soil

    Science.gov (United States)

    Milani, Narges; Hettiarachchi, Ganga M.; Kirby, Jason K.; Beak, Douglas G.; Stacey, Samuel P.; McLaughlin, Mike J.

    2015-01-01

    Zinc oxide (ZnO) nanoparticles may provide a more soluble and plant available source of Zn in Zn fertilizers due to their greater reactivity compared to equivalent micron- or millimetre-sized (bulk) particles. However, the effect of soil on solubility, spatial distribution and speciation of ZnO nanoparticles has not yet been investigated. In this study, we examined the diffusion and solid phase speciation of Zn in an alkaline calcareous soil following application of nanoparticulate and bulk ZnO coated fertilizer products (monoammonium phosphate (MAP) and urea) using laboratory-based x-ray techniques and synchrotron-based μ-x-ray fluorescence (μ–XRF) mapping and absorption fine structure spectroscopy (μ–XAFS). Mapping of the soil-fertilizer reaction zones revealed that most of the applied Zn for all treatments remained on the coated fertilizer granule or close to the point of application after five weeks of incubation in soil. Zinc precipitated mainly as scholzite (CaZn2(PO4)2.2H2O) and zinc ammonium phosphate (Zn(NH4)PO4) species at the surface of MAP granules. These reactions reduced dissolution and diffusion of Zn from the MAP granules. Although Zn remained as zincite (ZnO) at the surface of urea granules, limited diffusion of Zn from ZnO-coated urea granules was also observed for both bulk and nanoparticulate ZnO treatments. This might be due to either the high pH of urea granules, which reduced solubility of Zn, or aggregation (due to high ionic strength) of released ZnO nanoparticles around the granule/point of application. The relative proportion of Zn(OH)2 and ZnCO3 species increased for all Zn treatments with increasing distance from coated MAP and urea granules in the calcareous soil. When coated on macronutrient fertilizers, Zn from ZnO nanoparticles (without surface modifiers) was not more mobile or diffusible compared to bulk forms of ZnO. The results also suggest that risk associated with the presence of ZnO NPs in calcareous soils would be the

  18. THE FERTILITY DECLINE IN THE UNITED STATES: SCHOOLING AND INCOME

    DEFF Research Database (Denmark)

    Hansen, Casper Worm; Jensen, Peter Sandholt; Lønstrup, Lars

    2017-01-01

    This study investigates the determinants of the fertility transition in the United States from 1850 to the end of the 20th century. We find a robust negative relation between years of schooling and fertility. The magnitude of our baseline estimate suggests that the rise in schooling accounts...... for about 60% of the US fertility decline. In contrast, we find no evidence of a robust relation between income per capita and fertility. This pattern corroborates theories stressing the importance of human capital investments in generating a transition from high to low fertility....

  19. Patient-centered Fertility Care: From Theory to Practice

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarzadeh-Kenarsari

    2016-07-01

    Full Text Available Background & aim: Healthcare areas, especially fertility care (commonly accompanied with high emotions, as well as long-term and recurring treatment periods could exclusively benefit from patient-centered care (PCC. Despite evident advantages of PCC, this approach has not been practiced as a routine procedure in current clinical environments yet, even in western developed countries. Therefore, this review aimed to evaluate the significance and different aspects of PCC, while emphasizing on patient-centered fertility care, its challenges, and applicable recommendations in this regard. Methods: This narrative review was conducted on 29 relevant medical and clinical papers (published during 1990-2015 collected using various national and international databases (e.g., SID, Magiran, Medlib, Google scholar, Proquest, Pubmed, Wiley, Science direct, and Scopus. Key words and phrases used in this review were “infertility”, “fertility care”, “childlessness”, “patient-centered care”, “patient-centered fertility care” “shared decision-making”, “infertile patient preferences”, and “patient involvement in fertility care”. Results: According to the literature, implementation challenges of patient-centered fertility care were reported as different individual and organizational factors. These factors include lack of professional motivation to change, underestimating the significance of patient-centeredness by healthcare professionals, difficulty in translation of feedback into concrete measures, lack of time and financial resources, insufficient experience of healthcare professionals with regard to identification of needs and preferences of patients, traditional organizational culture, and common misconceptions. Conclusion: Promotion of patient-centered fertility services requires the identification of infertile needs and priorities of individuals, designation of interventional and supportive programs based on sociocultural

  20. Fragile Families and the Reproduction of Poverty

    OpenAIRE

    McLanahan, Sara

    2009-01-01

    In 1965, Daniel Patrick Moynihan warned that non-marital childbearing and marital dissolution were undermining the progress of African Americans. I argue that what Moynihan identified as a race-specific problem in the 1960s has now become a class-based phenomena as well. Using data from a new birth cohort study, I show that unmarried parents come from much more disadvantaged populations than married parents. I further argue that non-marital childbearing reproduces class and racial disparities...

  1. Nitrogen release, tree uptake, and ecosystem retention in a mid-rotation loblolly pine plantation following fertilization with 15N-enriched enhanced efficiency fertilizers.

    OpenAIRE

    Werner, Amy

    2013-01-01

    Nitrogen is the most frequently limiting nutrient in southern pine plantations.  Previous studies found that only 10 to 25% of applied urea fertilizer N is taken up by trees.  Enhanced efficiency fertilizers could increase tree uptake efficiency by controlling the release of N and/or stabilize N.  Three enhanced efficiency fertilizers were selected as a representation of fertilizers that could be used in forestry: 1) NBPT treated urea (NBPT urea), 2) polymer coated urea (PC urea), and 3) mono...

  2. The Effects of Mixed Source Fertilizer Application on Vertisol Fertility and Growth of Mustard

    Directory of Open Access Journals (Sweden)

    Jauhari Syamsiyah

    2017-09-01

    Full Text Available Soil fertility is a crucial factor determining the growth and yield of plants. The increase of nutrient content and availability in soil can be achieved by fertilization. A field experiment was conducted using a Randomized Completely Block Design (RCBD with two factors and three replications in order to study the effects of Mixed Source of Fertilizer (MSF application on the nutrient contents in Vertisol and its relationship to the growth and yield of mustard. The first factor was the three MSF formulas (F1, F2, F3 and second factor was the doses of MSF (0; 2.5; 5.0; 7.5; 10 Mg ha-1 applied to the soil. At the end of the experiment, the soil pH, CEC, organic-C, total-N, available-P and exchangeable-K contents were measured. The results show that there are no significant differences on the soil chemical characteristics, such as pH, organic-C content, available-P, exchangeable-K, -Ca and -Mg measured after application of different MSF formulas to the soil. Meanwhile, the increase of MSF doses applied to the soil significantly increases organic-C content, total-N, available-P and exchangeable-K in the soil. The significant increase of available-P (by 29.13% and total-N (by 24.1% occured after application of MSF at 5.0 Mg ha-1 and the increase of exchangeable-K (by 50% is achieved after application of 7.5 Mg ha-1, in comparison to that without MSF application. The height and fresh weight of mustard increase in accordance with the increase of MSF doses applied. The application of 10.0 Mg ha-1 MSF results in the highest height and fresh weight of the mustard up to 63.9% and 620%, respectively. The height and fresh weight of mustard are positively correlated to the total-N, available-P and exchangeable-K in the soil. The MSF is an alternative fertilizer that can be used to improve Vertisol fertility and plant growth.

  3. Economic Impact of Net Carbon Payments and Bioenergy Production in Fertilized and Non-Fertilized Loblolly Pine Plantations

    Directory of Open Access Journals (Sweden)

    Prativa Shrestha

    2015-08-01

    Full Text Available Sequestering carbon in forest stands and using woody bioenergy are two potential ways to utilize forests in mitigating emissions of greenhouse gases (GHGs. Such forestry related strategies are, however, greatly influenced by carbon and bioenergy markets. This study investigates the impact of both carbon and woody bioenergy markets on land expectation value (LEV and rotation age of loblolly pine (Pinus taeda L. forests in the southeastern United States for two scenarios—one with thinning and no fertilization and the other with thinning and fertilization. Economic analysis was conducted using a modified Hartman model. The amount of carbon dioxide (CO2 emitted during various activities such as management of stands, harvesting, and product decay was included in the model. Sensitivity analysis was conducted with a range of carbon offset, wood for bioenergy, and forest product prices. The results showed that LEV increased in both management scenarios as the price of carbon and wood for bioenergy increased. However, the results indicated that the management scenario without fertilizer was optimal at low carbon prices and the management scenario with fertilizer was optimal at higher carbon prices for medium and low forest product prices. Carbon payments had a greater impact on LEV than prices for wood utilized for bioenergy. Also, increase in the carbon price increased the optimal rotation age, whereas, wood prices for bioenergy had little impact. The management scenario without fertilizer was found to have longer optimal rotation ages.

  4. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Ethics Committee of the American Society for Reproductive Medicine. Fertility preservation and reproduction in patients facing gonadotoxic therapies: a committee opinion. Fertil Steril. 2013; 100:1224-31. Chow EJ, et al. Pregnancy after chemotherapy in male and female survivors of ...

  5. Fertility determinants in the oil region of Mexico.

    Science.gov (United States)

    Pick, J B; Tellis, G L; Butler, E W

    1989-01-01

    This study analyzes fertility determinants in the oil region of Mexico, consisting of the states of Veracruz, Tabasco, and Campeche. Data are from the 1980 Mexican census and the unit of analysis is the municipio. The regression models, in which the dependent variables of children ever born and child-woman ratio are examined, reveal religious variables to be most significant, with greater fertility for non-Catholics and persons with no religion than for Catholics. Also of great importance are economic variables. Literacy and urbanization, both "classical" Mexican fertility variables, reduce fertility. There are major differences among three urban/rural and three indigenous language subsamples. Results are discussed vis-a-vis demographic theories and prior research.

  6. Translocation of labelled fertilizer nitrogen in soil columns

    International Nuclear Information System (INIS)

    Haunold, E.; Zvara, J.

    1975-01-01

    The translocation of 15 labeled ammonium and nitrate fertilizer was studied under normal weather conditions for two years in columns filled with different soils. At the end of the experimental period, which usually lasted for 9 months, between 5.9-10.3% of the ammonium fertilizer was leached out, 33.7-50.1% remained in the soil and 39.5-59.7% was lost as gas. For nitrate nitrogen the figures were: 22.6-47.3% leached out, 16.7-40% remaining in the soil, 12.7-60.0% lost as gas. The ammonium fertilizer moving through the soil interchanged with 1-13% of the soil nitrogen, the nitrate fertilizer with only 0.5-2%

  7. Transformation of fertilizer nitrogen in soil

    International Nuclear Information System (INIS)

    Soechting, H.

    1980-01-01

    Pot experiments are described in which the transformations between nitrogen added as fertilizer urea, plant-assimilated nitrogen, and different chemical fractions of soil or added straw nitrogen were studied with 15 N as a tracer. The data indicated that: (a) The transformation of added fertilizer nitrogen to immobilized amide nitrogen is decreased with added decomposable organic carbon. The transformation to immobilized α-amino N is increased, on the other hand, by the addition of decomposable organic carbon. (b) The freshly immobilized amide nitrogen is more readily remineralized than the α-amino form. The immobilization of added nitrogen continues in the presence of growing plants. (c) Mineralization of nitrogen added as 15 N-labelled straw is also increased with increasing fertilizer-nitrogen additions. (author)

  8. Kinship and the decline of fertility.

    Science.gov (United States)

    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.

  9. [Explore the spatial and temporal patterns of water pollution in the Yincungang canal of the Lake Taihu basin, China].

    Science.gov (United States)

    Yang, Xiao-Ying; Luo, Xing-Zhang; Zheng, Zheng; Fang, Shu-Bo

    2012-09-01

    Two high-density snap-shot samplings were conducted along the Yincungang canal, one important tributary of the Lake Tai, in April (low flow period) and June (high flow period) of 2010. Geostatistical analysis based on the river network distance was used to analyze the spatial and temporal patterns of the pollutant concentrations along the canal with an emphasis on chemical oxygen demand (COD) and total nitrogen (TN). Study results have indicated: (1) COD and TN concentrations display distinctly different spatial and temporal patterns between the low and high flow periods. COD concentration in June is lower than that in April, while TN concentration has the contrary trend. (2) COD load is relatively constant during the period between the two monitoring periods. The spatial correlation structure of COD is exponential for both April and June, and the change of COD concentration is mainly influenced by hydrological conditions. (3) Nitrogen load from agriculture increased significantly during the period between the two monitoring periods. Large amount of chaotic fertilizing by individual farmers has led to the loss of the spatial correlation among the observed TN concentrations. Hence, changes of TN concentration in June are under the dual influence of agricultural fertilizing and hydrological conditions. In the view of the complex hydrological conditions and serious water pollution in the Lake Taihu region, geostatistical analysis is potentially a useful tool for studying the characteristics of pollutant distribution and making predictions in the region.

  10. Efficiency of soil and fertilizer nitrogen in relation to variety and application time, using N-15 labelled fertilizer. Part of a coordinated programme on agricultural nitrogen residues with particular reference to their conservation as fertilizers and behaviour as potential pollutants

    International Nuclear Information System (INIS)

    Park, H.

    1979-12-01

    A series of experiments with flooded rice were carried out on 36 locations to study the influence of rice variety, fertilizer source, frequency of fertilizer application and soil conditions on the uptake of fertilizer N and grain yield. 15 N-labelled fertilizer was used in this study. The results show that (i) urea is a better source of N than ammonium sulphate on saline soils and also for the leading local rice variety (Milyang 15). The new variety Tongil utilized ammonium sulphate more efficiently; (ii) Fertilizer was more efficiently utilized on high organic matter soils; (iii) Varieties differed in fertilizer use efficiency; (iv) Hybrid Tongil lines gave higher grain yields than the local varieties, and made better use of fertilizer N, especially on saline soil, when applied at transplanting; (v) Sulphur-coated urea gave higher yield than urea on saline soils (27-39%), virgin soils (20%) and unmatured soils (10%)

  11. Radiometric Analysis Of Different Fertilizers Consumed In Egypt

    International Nuclear Information System (INIS)

    El-Bahi, S.M.; Sroor, A.T.; Mousa, W.M.; Abd El-Halim, E.S.; Shenoda, A.A.

    2014-01-01

    The fertilizers are essential in agriculture as they supply nutrients to the farming fields. One of the sources of radioactivity other than those of natural origin is mainly due to extensive use of fertilizers. The concentrations of natural radionuclides, namely 226 Ra, 232 Th and 40 K, in different chemical fertilizers used in agricultural soil were analyzed using gamma spectrometry with a high purity germanium (HPGe) detector in order to assess the implications of the extended use of phosphate fertilizers in recent years. The radium equivalent activity (Raeq), external hazard index (Hex) and absorbed dose in air for all samples were calculated. The 226 Ra content was very high for some samples under investigation and was found to vary from 33.41 Bq/kg to 1162.39 Bq/kg. This can result in a significant radiation exposure if the rock and fertilizer are handled in places with poor ventilation that could lead to radon accumulation. The concentrations of eight elements (Cd, Cu, Fe, Mg, Mn, Ni, Pb and Zn) in the samples under investigation were determined by flame atomic absorption spectrometer (FAAS). The results showed that the fertilizer samples contained less heavy metals than those used in world wide. Accepted May 2014.

  12. Concentrations of Heavy Metals in NPK Fertilizers Imported in Serbia

    Directory of Open Access Journals (Sweden)

    Jelena Milinović

    2008-01-01

    Full Text Available Concentrations of Pb, Cd, Cu and Mn in sixteen NPK fertilizers imported and widely used in Serbia were determined by flame atomic absorption spectrometry (AAS. The results show that contents of heavy metals varied significantly in different fertilizers dependingon N:P:K ratio and fertilizer origin. Pb and Cd contents in water solution of fertilizers occurred at low ranges: 2.0-3.1 and 0.03- 1.56 mg/kg, respectively. An NPK (15:15:15 fertilizer from Romania was found to contain the highest concentration of Pb and Cd as impurities. Cu content, ranging from 7.1 to 974.7 mg/kg, was the highest in coloured fertilizers from Hungary, the Netherlands and Greece. Mn value in a Hungarian NPK product (10:10:20 exceeds the average Mn value in soil. The data indicate variable contents of heavy metals in fertilizers, some of which are significantly higher than natural concentrations in soil, which suggests that they need to be continuously monitored.

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

    Science.gov (United States)

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

    2016-04-19

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

  14. Operational optimization of organic fertilizer application in greenhouse crops

    NARCIS (Netherlands)

    Evert, van F.K.; Visser, de P.H.B.; Heinen, M.

    2006-01-01

    Organic fertilizers are the only fertilizers used in organic greenhouse horticulture. The nitrogen (N) in these fertilizers must be mineralized before it can be taken up by the crop. This makes it a challenge to minimize N losses while ensuring that adequate N is available to the crop at all times.

  15. Trace determination of uranium in fertilizer samples by total ...

    Indian Academy of Sciences (India)

    Uranium is reported to be present in phosphate fertilizers. The recovery of uranium from the fertilizers is important because it can be used as fuel in nuclear reactors and also because of environmental concerns. For both these activities suitable method of uranium determinations at trace levels in these fertilizers are required.

  16. A socio-economic survey among cocoa farmers on fertilizer ...

    African Journals Online (AJOL)

    A socio-economic survey was conducted in some districts of the six cocoa growing regions of Ghana to provide information for adjustment of government's fertilizer use policy on cocoa farms. The study's objectives were to determine the proportion of farmers applying fertilizer to their farms, investigate the fertilizer application ...

  17. Trace determination of uranium in fertilizer samples by total ...

    Indian Academy of Sciences (India)

    the fertilizers is important because it can be used as fuel in nuclear reactors and also because of en- vironmental concerns. ... The amounts of uranium in four fertilizer samples of Hungarian origin were determined by ... TXRF determination of uranium from phosphate fertilizers of Hungarian origin and the preliminary results ...

  18. Fertility preservation: a pilot study to assess previsit patient knowledge quantitatively.

    Science.gov (United States)

    Balthazar, Ursula; Fritz, Marc A; Mersereau, Jennifer E

    2011-05-01

    To provide a quantitative assessment of patient knowledge about fertility and fertility preservation treatment options before the initial fertility preservation consultation at a university-based fertility preservation center. Prospective pilot survey containing 13 items assessing patient knowledge about fertility preservation, including the available treatment options and their requirements, success rates, and associated risks. University-based IVF center. Women aged 18 to 41 years with illnesses requiring treatments posing a serious threat to future fertility who were referred for fertility preservation consultation between April 2009 and June 2010. None. Knowledge score. Forty-one eligible patients were identified, and all completed surveys before their consultation. A knowledge score was generated for each patient with 1 point awarded for each correct answer. Overall, patients had poor previsit fertility preservation knowledge (mean score 5.9±2.7). Higher knowledge scores were correlated with personal experience with infertility and previous exposure to fertility preservation treatment information. There was no correlation between knowledge score and age, relationship status, pregnancy history, education, or income. Patients seen for fertility preservation consultation at our university-based center generally tend to be in their early 30s, white, well educated, and married. Previsit knowledge about fertility preservation treatment options was poor and did not correlate with age, education, and relationship status. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  19. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available Sorry, you need to enable JavaScript to visit this website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for ... for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult survivors of childhood cancer ...

  20. The cultural evolution of fertility decline

    Science.gov (United States)

    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

  1. Organic fertilization in cherry tomato plants

    Directory of Open Access Journals (Sweden)

    Janini Tatiane Lima Souza Maia

    2013-03-01

    Full Text Available Cherry tomato (Solanum lycopersicum is highly demanding with regard to mineral nutrients. The use of animal manure shows to be an efficient and sustainable fertilization way for this crop. This study aimed to evaluate the effect of different doses of cattle manure in the vegetative and reproductive growth of cherry tomato. The experiment was conducted in a greenhouse at the Plant Science Department of Universidade Federal de Vicosa, using a completely randomized experimental design with 5 treatments and 4 replications, besides 1 control treatment using chemical fertilizer as a source of NPK. After 45 days from the beginning of the experiment, the number of leaves, flowers, and fruits, the dry mass of leaves, stem, flowers, fruits, and roots, the stem length, and the root volume were evaluated. The nutrient content in leaves, stem, and roots was also evaluated. Plants grown with chemical fertilizer obtained a lower average for all phytotechnical variables analyzed. The number of leaves and fruits, and the production of dry matter of leaves, fruits, and stems showed an upward linear response with an increase in manure doses. The Ca, Mg, and S leaf contents were higher in the treatment with chemical fertilization.

  2. Fate of nitrogenous fertilizers in forest soil

    International Nuclear Information System (INIS)

    Pang, P.C.K.

    1984-01-01

    The fate of the nitrogenous fertilizers through the processes of denitrification, ammonia volatilization, immobilization and uptake by a conifer is determined, with the aid of 15 N-labelled fertizers. The foliage of Douglas-fir was able to absorb gaseous ammonia under optimal conditions. Denitrification and immobilization of fertilizer-N by forest soil were highest with forest floor samples and decreased with depth. Laboratory studies with four-year-old Douglas-fir demostrated that a higher quantity of fertilizer-N was utilized by trees when the nitrogen was supplied as NO 3 - rather than NH 4 + . (M.A.C.) [pt

  3. SEWAGE SLUDGE AS AN INGREDIENT IN FERTILIZERS AND SOIL SUBSTITUTES

    Directory of Open Access Journals (Sweden)

    Anna Grobelak

    2016-06-01

    Full Text Available In Poland, sludge management especially in medium and small sewage treatment plants is still a significant problem. According to data from the Central Statistical Office and the report on the implementation of the National Urban Wastewater Treatment Program (in polish KPOŚK land application of sewage sludge remains one of the main methods, although there has been considerable interest known: 'application for other purposes ", where the preparation of composts and fertilizers is included. The use of fertilizer produced from sewage sludge (compost, granules, organic and mineral fertilizers, is regulated by the Act on fertilizers and fertilization, and the relevant implementing rules. For example, they define the test procedure (concerning the quality of fertilizers to enable appropriate permissions to market this type of fertilizers. There is still only several technologies existing on the Polish market dedicated to production of fertilizers in advanced technologies of sewage sludge treatment. Usually the treatment plants are trying to obtain the necessary certificates for generated fertilizers (including composts, or soils substitutes. The advantages of these technologies should be no doubt: the loss of waste status, ability to store the fertilizer and unlimited transportation between areas, sanitization of the product (as a result of the use of calcium or sulfur compounds or temperature should be an alternative for drying technology. While the disadvantages are primarily the investment costs and time consuming certification procedures. However, these solutions enable to maintain the organic matter and phosphorus as well as greater control over possible pollution introduced into the soil.

  4. Assessment of soil nutrient depletion and its spatial variability on smallholders' mixed farming systems in Ethiopia using partial versus full nutrient balances

    NARCIS (Netherlands)

    Haileslassie, A.; Priess, J.; Veldkamp, E.; Teketay, D.; Lesschen, J.P.

    2005-01-01

    Soil fertility depletion in smallholder farms is one of the fundamental biophysical causes for declining per capita food production in Ethiopia. In the present study, we assess soil nutrient depletion and its spatial variability for Ethiopia and its regional states, using nutrient balances as a

  5. Fertility prognosis for infertile couples

    DEFF Research Database (Denmark)

    Bostofte, E; Bagger, P; Michael, A

    1993-01-01

    OBJECTIVE: To develop a fertility prognosis model for infertile couples. DESIGN: Prospective follow-up study. PARTICIPANTS: In the period November 30, 1977 to June 1, 1985, 321 consecutive couples were investigated for infertility at Hvidovre University Hospital. Investigation of the female...... MEASURE: The Cox regression model was used to predict the time required to conceive based on informations provided by fertility investigations. RESULTS: Three of 16 prognostic variables (the period of infertility, the female infertility factor, and the P-test) possess significant prognostic information...

  6. SOCIAL DETERMINANTS OF LOW FERTILITY IN BRAZIL.

    Science.gov (United States)

    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.

  7. Fertility and the changing female educational attainment in Croatia

    Directory of Open Access Journals (Sweden)

    Čipin Ivan

    2016-01-01

    Full Text Available This paper investigates the aggregate relationship between cohort fertility and female educational attainment in Croatia. Numerous demographic studies have examined the link between fertility and the level of education. However, newer research indicates that the field of education might also play a role when trying to explain fertility behavior. We contribute to existing literature on macro-level factors related to reproductive outcomes by considering both the level and field of education as possible sources of cohort fertility differentials. The main goal of the present study is to assess the effect of structural changes in educational attainment on cohort fertility decline by means of demographic decomposition techniques. Our analysis is based on detailed 2011 Census data, which provide information on the number of livebirths by mother’s year of birth, birth order, marital status and educational attainment (i.e. the level and field of education. The results of our decomposition analyses reveal the dominance of the structural effect in explaining the overall completed fertility decline in Croatia. We assumed that the changing distribution of women by field of education at least partially accounts for the observed patterns in completed fertility but found no strong evidence in support of the outlined hypothesis.

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

    African Journals Online (AJOL)

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

  9. Immigrant fertility in Sweden, 2000-2011: A descriptive note

    Directory of Open Access Journals (Sweden)

    Lotta Persson

    2014-03-01

    Full Text Available Background: Modern Scandinavian population registers provide excellent data sources that allow a user to quickly gain an impression of the level of fertility and its structure across subpopulations. This may also allow the analyst to check a feature of the much-cited disruption hypothesis, at least in part. Objective: The purpose of this note is to exploit this potential to give an overview of the structure of recent total fertility after immigration to Sweden from various groups of sending countries, separately for males and females. In the process we demonstrate to what extent the post-migration fertility compensation which is part of the fertility disruption hypothesis is fulfilled in our study population. Due to the nature of our data we have refrained from studying fertility before migration. Methods: Based on data from a combination of two Swedish administrative registers (the Historic Population Register and the Multi-Generation Register that cover both men and women in the entire population for the years 2000-2011, we compute and plot TFR-like age-cumulated fertility levels, specific for years since immigration, for six groups of sending countries, separately for men and women. Results: We find that the post-migration fertility compensation specified as part of the fertility disruption hypothesis is visibly confirmed in our Swedish study population for female European immigrants from non-EU countries and for female immigrants from non-European countries with a low or medium UN Human Development Index, but not so for other female immigrants, i.e. not for those who come from a Nordic country or from a non-Nordic EU country, and not for female immigrants from a non-European country with a high Human Development Index, including the United States. We find mild but less conclusive evidence for the same feature for males. Conclusions: This shows that at least as far as post-migration fertility compensation is concerned, the disruption

  10. Fertility in Austria, Germany and Switzerland:Is there a Common Pattern?

    Directory of Open Access Journals (Sweden)

    Tomáš Sobotka

    2012-08-01

    Full Text Available This article reviews major similarities and differences in period and cohort fertility in Austria, Germany and Switzerland. These three countries share a long history of low fertility and currently belong to countries with the lowest cohort fertility rates globally. The study highlights persistent differences in fertility and family patterns between Eastern and Western Germany, which are often rooted in pre-unification contrasts and can be partly linked to continuing differences in institutional set-up and norms on organised childcare, living arrangements and maternal employment. The remarkable stability in period fertility over the last 30 years (with the exception of Eastern Germany is illustrated with various indicators and discussed on the backdrop of recent reversals in European fertility trends. This stability in fertility levels contrasts with the long-term shift in childbearing towards less stable living arrangements (especially in Eastern Germany, including a high share of single mothers. The study also discusses a relatively small but persistent negative impact of the ongoing shift towards a late timing of childbearing on period fertility in the region. It highlights the educational gradient in fertility, which can be largely attributed to elevated childlessness rates among women with a higher educational degree. Migrant women have on average higher fertility rates than “native-born” women, but their net positive impact on aggregate fertility rates has diminished over time and has become negligible in Germany. A concluding discussion suggests that Austria, Germany and Switzerland share a common pattern of low fertility that sets these countries apart from other regions in Europe.

  11. Advantage of Sesame and Cowpea Intercrops in Different Fertilizer Application Systems

    Directory of Open Access Journals (Sweden)

    Jasem Aminifar

    2017-04-01

    Full Text Available To investigate the effects of different fertilizer applications and sesame/cowpea intercropping systems on soil fertility, a split plot experiment based on randomized complete block design was conducted in Fasa, Fars province, during 2014. The main plots were five fertilizer levels consisted of: using chemical fertilizers nitrogen+phosphorous (F1, organic fertilizers (F2, biofertilizers (F3, 50% chemical fertilizer + 50% organic fertilizer (F4 and 50% chemical fertilizer + 50% biofertilizer (F5, and sub plots consisted of: sole cropping of sesame (M1, sole cropping of cowpea (M2, 50:50 sesame-cowpea intercropping (M3, 75:25 sesame-cowpea intercropping (M4 and 25:75 sesame-cowpea intercropping (M5. The results showed that soil fertility and cropping systems affected the yield and yield components of sesame and cowpea significantly. The highest yield of sesame (1292.6 kg.ha-1, and cowpea (3772.4 kg.ha-1 were obtained from their sole croppings. Among the applications of fertilizer, the highest yield of sesame (950.49 kg.ha-1 and cowpea (2582.50 kg.ha-1 belonged to bioorganic and biofertilizer treatments, respectively. In spite of these results, the highest land equivalent ratio (LER belonged to F4 (1.24 and M3 (1.03 treatments. In general, according to the results, it seems that 50:50 sesame-cowpea intercropping (M3 and application of 30 kg.ha-1 N + 50 kg.ha-1 P + 150 kg.ha-1 bio-organic fertilizer (F4, may reduce application of chemical fertilizers and be beneficial to sesame-cowpea intercropping system.

  12. Risk for borderline ovarian tumours after exposure to fertility drugs

    DEFF Research Database (Denmark)

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

    2015-01-01

    numbers. To obtain information on use of fertility drugs, hospital files and medical records of infertility-associated visits to all Danish fertility clinics were collected and supplemented with information from the Danish IVF register. We used case-cohort techniques to calculate rate ratios (RRs......STUDY QUESTION: Do fertility drugs increase the risk for borderline ovarian tumours, overall and according to histological subtype? SUMMARY ANSWER: The use of any fertility drug did not increase the overall risk for borderline ovarian tumours, but an increased risk for serous borderline ovarian...... tumours was observed after the use of progesterone. WHAT IS KNOWN ALREADY: Many epidemiological studies have addressed the connection between fertility drugs use and risk for ovarian cancer; most have found no strong association. Fewer studies have assessed the association between use of fertility drugs...

  13. Gender inequality and the risk of HIV among married couples in North India.

    Science.gov (United States)

    Bloom, Shelah S; Agrawal, Alpna; Singh, Kaushalendra K; Suchindran, Chirayath M

    2015-01-01

    This study investigated the distribution and determinants of HIV risks among married couples in North India. Gender inequality emerged as a potential driver of HIV risks in this region. Data collection took place in 2003 in a probability survey of 3385 couples living in India's most populous state - Uttar Pradesh - and Uttaranchal. Couples' analyses utilizing generalized estimating equations showed that compared with husbands, wives were less knowledgeable about HIV (OR = 0.31, 95% CI = 0.27-0.36), more likely to consider themselves at risk for infection (OR = 6.86, 95% CI = 4.65-10.13), and less likely to feel that a wife had the right to refuse sex with her husband (OR = 0.50, 95% CI = 0.44-0.58). The proportion of husbands reporting non-marital sex in the past year was 7.1% and transactional sex in the past year, 2.2%. Among their wives, 73.4% were unaware of their husbands' non-marital sexual behaviors and only 28.9% of husbands reported condom use during their last non-marital sexual encounter. Logistic regression analyses showed that husbands' alcohol use, husbands' mobility, and urban residence were positively associated with husbands' non-marital sexual behaviors adjusting for other covariates. The data demonstrate that HIV prevention programs among couples in North India should consider both sexual risks and gender inequalities which potentially fuel HIV spread in this region.

  14. Influence of Organic and Inorganic Sources of Fertilizer on Growth ...

    African Journals Online (AJOL)

    Influence of Organic and Inorganic Sources of Fertilizer on Growth and Leaf Yield of Kale ... Journal of Agriculture, Science and Technology ... fertilizer gave leaf yields comparable to those applied with exclusively inorganic sources of fertilizer.

  15. Enteropathogenic bacterial contamination of a latosol following application of organic fertilizer

    Directory of Open Access Journals (Sweden)

    Pedro Alexandre Escosteguy

    2015-10-01

    Full Text Available Poultry manure is used as fertilizer in natura, but little is known about whether it contaminates the soil with pathogenic organisms. The aim of this study was to assess the effects of organic, organomineral and mineral fertilizers on soil contamination by enteric pathogens, using poultry manure as the organic fertilizer. Manure was applied in field experiments at rates of 7.0 ton. ha-1 (maize crop, 2008/2009, 8.0 ton. ha-1 (wheat crop, 2009 and 14 ton. ha-1 (maize crop, 2010/2011. Organomineral fertilizer was applied at the same rates but was comprised of 50% manure and 50% mineral fertilizer. At 30 and 70 days after fertilization, the organic fertilizer and the upper 0-5 cm layer of the soil were tested for the presence of helminth eggs and larvae and enteropathogenic bacteria. Fecal and non-fecal coliforms (Escherichia coli and Clostridium perfringes were found in the organic fertilizer, but neither Salmonella spp. nor enteroparasites were detected. The population of enteropathogenic bacteria in the soil was similar among the treatments for all crops at both evaluation times. The population of thermotolerant coliforms in the organic fertilizer was larger than the maximum level allowed in Brazil, but neither the organic or nor the organomineral fertilizer contaminated the soil.

  16. Changing fertility patterns and policies in the third world.

    Science.gov (United States)

    Mcnicoll, G

    1992-01-01

    Different patterns of fertilty transition are apparent in developing countries. Theories of fertility decline are appropriate because demographic analysis has become situation specific rather than general. Pretransition fertility patterns and the onset of decline are provided. Fertility transition patterns are also supplied, including a regional overview for Latin America, east and Southeast Asia, South Asia, West Asia and North Africa, and sub-Saharan Africa. The specialized cases of China, India, Bangladesh, Thailand and Indonesia, and Brazil are also presented. The fertility determinant models of Bongaarts, Davis and Blake, Hobcraft and Little, Ryder, and Henry are used as examples of proximate determinant models. Data collection was possible on a grand scale with contraceptive knowledge, attitudes, and practice (KAP) surveys and the World Fertility Surveys and Demographic and Health Surveys. Criticism has focused on the scope of these surveys which provide at best proximate determinants and differentiate fertility by standard socioeconomic factors. Data are also obtained on small populations from piecing together records and from quasi-anthropological fieldwork. Historical demography relies on family reconstitution. Longitudinal studies are few in number. The largest and most effective fieldwork station is at Matlab in Bangladesh. Caldwell has provided anthropological methods applicable to fertility study and makes use of teamwork. In Latin America, fertility has fallen by 40% since the 1960s. Bolivia, Guatemala, Honduras, Nicaragua, El Salvador, and Haiti have changed very little. Taiwan and South Korea provide examples of economic growth with equity in East and Southeast Asia. In heterogenous South Asia, decline has been slow and uneven. West Asia and North Africa have high fertility with the exception of Egypt which is in the early stages of transition. The smallest declines are found in sub-Saharan Africa, and are complicated by the AIDS epidemic.

  17. Fertilization Management of Paddy Fields in Piedmont (NW Italy

    Directory of Open Access Journals (Sweden)

    Laura Zavattaro

    2008-09-01

    Full Text Available A well-documented analysis of fertilization management techniques in use by farmers in a given region is the first step to improving the management standards of agronomic practices. The aim of this work was to summarize the fertilization management that farmers normally utilize for the rice crop in the Piedmont Region of Northwest Italy, and to analyze its agronomic and environmental sustainability. On average, 127 kg ha-1 of N, 67 kg ha-1 of P2O5, and 161 kg ha-1 of K2O were applied to the rice crop. Inorganic fertilizers were used on most of the surface. Calcium cyanamide was the most widely used slow-release product. Commercial organic compounds were spread on about 32% of the paddy surface, while farmyard manure was distributed over 6% of the surface. Organic-mineral products were also widely used. One fourth of the paddy surface received only inorganic products. Using organic or organic-mineral fertilizers together with inorganic products was the most common strategy (55% of the paddy surface. In most cases, N and P fertilization was balanced with crop removal. The N soil surface balance was in the ± 50 kg range for 77% of the surface, P fertilization was less than removal for 53% of the surface, whereas K fertilization was excessive (surplus >100 kg ha-1 for 53% of the surface. The nutrient balance was affected by the widespread practice of burning straw after harvest (66% of the paddy surface. The farmers modulated fertilization according to the rice variety requirements and tolerance to high N supply. The largest nutrient surplus was associated with stocking farms. Inefficient use of fertilizers that should be avoided to improve the territorial nutrient balance were then outlined, and possible specific actions were proposed.

  18. Fertilization Management of Paddy Fields in Piedmont (NW Italy

    Directory of Open Access Journals (Sweden)

    Laura Zavattaro

    Full Text Available A well-documented analysis of fertilization management techniques in use by farmers in a given region is the first step to improving the management standards of agronomic practices. The aim of this work was to summarize the fertilization management that farmers normally utilize for the rice crop in the Piedmont Region of Northwest Italy, and to analyze its agronomic and environmental sustainability. On average, 127 kg ha-1 of N, 67 kg ha-1 of P2O5, and 161 kg ha-1 of K2O were applied to the rice crop. Inorganic fertilizers were used on most of the surface. Calcium cyanamide was the most widely used slow-release product. Commercial organic compounds were spread on about 32% of the paddy surface, while farmyard manure was distributed over 6% of the surface. Organic-mineral products were also widely used. One fourth of the paddy surface received only inorganic products. Using organic or organic-mineral fertilizers together with inorganic products was the most common strategy (55% of the paddy surface. In most cases, N and P fertilization was balanced with crop removal. The N soil surface balance was in the ± 50 kg range for 77% of the surface, P fertilization was less than removal for 53% of the surface, whereas K fertilization was excessive (surplus >100 kg ha-1 for 53% of the surface. The nutrient balance was affected by the widespread practice of burning straw after harvest (66% of the paddy surface. The farmers modulated fertilization according to the rice variety requirements and tolerance to high N supply. The largest nutrient surplus was associated with stocking farms. Inefficient use of fertilizers that should be avoided to improve the territorial nutrient balance were then outlined, and possible specific actions were proposed.

  19. Assessment of Fertility Status of Soils Supporting Coconut ( Cocus ...

    African Journals Online (AJOL)

    Coconut cultivation is mostly practiced in the Western and Central regions of Ghana. Information on the fertility status of the soils on which coconuts are grown and possible fertilizer recommendation is not common. Since coconut yield is generally related to the fertility status of the soil, a study was conducted to evaluate the ...

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

    African Journals Online (AJOL)

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

  1. Wood quality changes caused by mineral fertilization

    Directory of Open Access Journals (Sweden)

    Carlos Roberto Sette Jr

    2014-06-01

    Full Text Available The diverse and important use of wood from fast growth eucalyptus plantations requires the analysis of the effect of mineral fertilizers on wood quality. The objective of this study was to evaluate the anatomical characteristics and wood density from Eucalyptus grandis trees (3 m x 2 m spacing fertilized with potassium and sodium (at planting, 6 th and 12th month. Fifteen (15 6 years old eucalyptus trees were selected (5 trees/treatment, cut and wood samples at DBH (1,3 m were taken for anatomical characteristics (fiber and vessels and wood density analysis. Results showed that eucalyptus trees treated with mineral fertilizers did not show significant alteration in average wood density, with radial profile model common to all three treatments, characterized by a values increase in the region next to the pith, toward to bark. Mineral fertilization influenced wood anatomical characteristics: treatment with sodium was characterized by thinner walls and lumen larger diameter; in treatment with potassium, larger vessels were detected.

  2. Availability of residual nitrogen from fertilizers in soil

    International Nuclear Information System (INIS)

    Jakovljevic, M.; Filipovic, R.; Petrovic, M.

    1983-01-01

    The plant availability of residual fertilizer nitrogen for the next crop was studied in chernozem and pseudogley soils. Release of nitrogen was examined after incubation at 3 and 30 0 C. It was found that the use of increased doses of nitrogen fertilizer (ammonium nitrate) led to an increased release of residual fertilizer nitrogen into plant available forms. The release of this nitrogen fraction was 5-10 times faster in comparison with the remaining soil nitrogen. (author)

  3. Availability of residual nitrogen from fertilizers in soil

    Energy Technology Data Exchange (ETDEWEB)

    Jakovljevic, M.; Filipovic, R.; Petrovic, M. (Institut za Primeni Nuklearne Energije u Poljoprivedri, Veterinarstvu i Sumarstvu, Zemun (Yugoslavia))

    1983-05-01

    The plant availability of residual fertilizer nitrogen for the next crop was studied in chernozem and pseudogley soils. Release of nitrogen was examined after incubation at 3 and 30/sup 0/C. It was found that the use of increased doses of nitrogen fertilizer (ammonium nitrate) led to an increased release of residual fertilizer nitrogen into plant available forms. The release of this nitrogen fraction was 5-10 times faster in comparison with the remaining soil nitrogen.

  4. Influence of long-term fertilization on soil physicochemical properties in a brown soil

    Science.gov (United States)

    Li, Dongdong; Luo, Peiyu; Han, Xiaori; Yang, Jinfeng

    2018-01-01

    This study aims to explore the influence on soil physicochemical properties under a 38-y long-term fertilization in a brown soil. Soil samples (0-20 cm)were taken from the six treatments of the long-term fertilization trial in October 2016:no fertilizer (CK), N1(mineral nitrogen fertilizer), N1P (mineral nitrogen and phosphate fertilizer), N1PK (mineral nitrogen, phosphate and potassic fertilizer), pig manure (M2), M2N1P (pig manure, mineral nitrogen and phosphate fertilizer).The results showed thatthe long-term application of chemical fertilizers reduced soil pH value, while the application of organic fertilizers increased pH value. Fertilization significantly increased the content of AHN, TN and SOM. Compared with the CK treatment and chemical fertilizer treatments, organic fertilizer treatments significantly increased the content of AP and TP. The content of AK and TK were no significant difference in different treatment.

  5. Distribution Of 15N Fertilizer Added To Sandy Soil Under Drip Irrigation System As Affected By Irrigation Frequencies

    International Nuclear Information System (INIS)

    GADALLA, A.M.; GALAL, Y.G.M.; EL-GENDY, R.W.; ISMAIL, M.M.; EL-DEGWY, S.M.; KASSAB, M.F.

    2009-01-01

    Neutron moisture meter and stable nitrogen isotope ( 15 N) were used to follow horizontal and vertical water movement and N-fertilizer added to soil before and after irrigation. The data indicated that soil moisture distribution and values of total hydraulic potential depend on soil moisture content. Characterization of nitrogen in soil for all sites around the emitter indicated spatial variability with different soil depths due to leaching and volatilization processes. Moreover, water movement and flow direction greatly were characterized by active evaporation depth which was 30 cm.

  6. Confinement lowers fertility rate of helmeted guinea fowl ( Numida ...

    African Journals Online (AJOL)

    ... common game bird in Africa and there have been efforts to domesticate it for use as a source of human food. An important obstacle in successful domestication of guinea fowl is their low fertility rate.We studied the effects of semi-confinement on the fertility rates of helmeted guinea fowl by comparing egg fertility, hatch rate ...

  7. [Stress and fertility].

    Science.gov (United States)

    Ősapay, György; Ősapay, Klára

    2015-08-30

    In Western countries, sperm quality and fertility of men significantly worsened. Female infertility does not show a better trend either. Subtle defects in the reproductive functions can not be explained by the current methods, and "unexplained infertility" is becoming a more common diagnosis. Every year 1 million couples seek expensive and time consuming fertility treatment in the world. Deeper understanding of an unhealthy lifestyle and the environmental damages may lead to personalized treatments to increase the chance of conception.The effects of various stressors on the male and female reproductive performance were scientifically substantiated by Selye and coworkers in 1976. Cognitive therapy methods can be applied against emotional stressors, supplementation by antioxidants against reactive oxygen compounds, and administration of vitamins and trace elements, especially when deficiency is found, may help before medical intervention on a rational and economical way in the fight against infertility.

  8. A physical theory on placement of fertilizers

    NARCIS (Netherlands)

    Wit, de C.T.

    1953-01-01

    A theory was developed enabling calculation of the effect of any placement method of fertilizer on yield if the effect of one method is known.

    This theory was based on the following established facts. The reactions between soil and fertilizer rate are the same for broadcasting and placement

  9. Ovarian Cysts and Fertility: Is There a Connection?

    Science.gov (United States)

    ... Is there a link between ovarian cysts and fertility? Answers from Charles Coddington, M.D. Some ovarian cysts can be associated with decreased fertility. However, it depends on the type of ovarian ...

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

    OpenAIRE

    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 counselli...

  11. Comparison of digestion methods to determine heavy metals in fertilizers

    Directory of Open Access Journals (Sweden)

    Ygor Jacques Agra Bezerra da Silva

    2014-04-01

    Full Text Available The lack of a standard method to regulate heavy metal determination in Brazilian fertilizers and the subsequent use of several digestion methods have produced variations in the results, hampering interpretation. Thus, the aim of this study was to compare the effectiveness of three digestion methods for determination of metals such as Cd, Ni, Pb, and Cr in fertilizers. Samples of 45 fertilizers marketed in northeastern Brazil were used. A fertilizer sample with heavy metal contents certified by the US National Institute of Standards and Technology (NIST was used as control. The following fertilizers were tested: rock phosphate; organo-mineral fertilizer with rock phosphate; single superphosphate; triple superphosphate; mixed N-P-K fertilizer; and fertilizer with micronutrients. The substances were digested according to the method recommended by the Ministry for Agriculture, Livestock and Supply of Brazil (MAPA and by the two methods 3051A and 3052 of the United States Environmental Protection Agency (USEPA. By the USEPA method 3052, higher portions of the less soluble metals such as Ni and Pb were recovered, indicating that the conventional digestion methods for fertilizers underestimate the total amount of these elements. The results of the USEPA method 3051A were very similar to those of the method currently used in Brazil (Brasil, 2006. The latter is preferable, in view of the lower cost requirement for acids, a shorter digestion period and greater reproducibility.

  12. Biodegradation of aliphatic vs. aromatic hydrocarbons in fertilized arctic soils

    Science.gov (United States)

    Braddock, J.F.

    1999-01-01

    A study was carried out to test a simple bioremediation treatment strategy in the Arctic and analyze the influence of fertilization the degradation of aliphatic and aromatic hydrocarbons, e.g., pristine, n-tetradecane, n-pentadecane, 2-methylnaphthalene, naphthalene, and acenaphthalene. The site was a coarse sand pad that once supported fuel storage tanks. Diesel-range organics concentrations were 250-860 mg/kg soil at the beginning of the study. Replicate field plots treated with fertilizer yielded final concentrations of 0, 50, 100, or 200 mg N/kg soil. Soil pH and soil-water potentials decreased due to fertilizer application. The addition of fertilizer considerably increased soil respiration potentials, but not the populations of microorganisms measured. Fertilizer addition also led to ??? 50% loss of measured aliphatic and aromatic hydrocarbons in surface and subsurface soils. For fertilized plots, hydrocarbon loss was not associated with the quantity of fertilizer added. Losses of aliphatic hydrocarbons were ascribed to biotic processes, while losses of aromatic hydrocarbons were due to biotic and abiotic processes.

  13. Women's Agency and Fertility: Recent Evidence from Egypt.

    Science.gov (United States)

    Samari, Goleen

    2017-08-01

    Fertility reached a two decade high of 3.5 births per woman in Egypt in 2014. Lower status of women is associated with higher fertility. Majority of the studies on women's agency and fertility rely on individual level cross-sectional data from South Asia, which limits the understanding of variation among communities and the direction of the relationship between women's agency and fertility in other global contexts. This study examines the relationship between women's agency and fertility longitudinally and among communities in the most populous country in the Middle East - Egypt. For 3,795 ever married women 15 to 49 years old in the 2006 and 2012 Egyptian Labor Market Panel Survey, multilevel models are estimated for having given birth and number of births between 2006 and 2012. Contrary to expectation, women with more agency with greater participation in household decision-making and mobility are, in fact, more likely to have had a birth and have a greater total number of births. Only women with more egalitarian attitudes are associated with fewer births. Community membership explains 5% of the variation in fertility. Since social norms in Egypt favor a higher number of births and labor market participation among women is low, women with agency could be fulfilling social expectations of having children and choosing to have more children.

  14. Overview Chapter 6: The diverse faces of the Second Demographic Transition in Europe

    Directory of Open Access Journals (Sweden)

    Tomáš Sobotka

    2008-07-01

    Full Text Available This chapter discusses the concept of the second demographic transition (SDT and its relevance for explaining the ongoing changes in family and fertility patterns across Europe. It takes a closer look at the shifts in values and attitudes related to family, reproduction, and children, and their representation in different chapters in this collection. It re-examines the link between the second demographic transition and fertility, highlights its strong positive association with fertility at later childbearing ages, and suggests that the transition does not necessarily lead to sub-replacement fertility levels. Subsequently, it provides an extensive discussion on the progression of the SDT behind the former 'Iron Curtain.' To explain some apparent contradictions in this process, it employs a conceptual model of 'readiness, willingness, and ability' (RWA advocated by Lesthaeghe and Vanderhoeft (2001. It also explores the multifaceted nature of the second demographic transition between different social groups, and points out an apparent paradox: whereas lower-educated individuals often embrace values that can be characterised as rather traditional, they also frequently manifest family behaviour associated with the transition, such as non-marital childbearing, high partnership instability, and high prevalence of long-term cohabitation. This suggests that there may be two different pathways of the progression of the second demographic transition. The concluding section points out the role of structural constraints for the diffusion of the transition among disadvantaged social strata, highlights the importance of the 'gender revolution' for the SDT trends, and discusses the usefulness of the SDT framework.

  15. Fertility and its relationship with sociocultural factors in Kuwaiti society.

    Science.gov (United States)

    Al-Kandari, Y Y

    2007-01-01

    The aim of this study was to examine the effect of some sociocultural variables on the fertility of Kuwaiti women. A questionnaire was administered to a sample of 7749 married women (aged 15-78 years) selected randomly from 10 primary health care clinics in Kuwait. The fertility rate was 3.58 live births per woman. Fertility was higher among Sunni Muslim women, those of Bedouin ethnicity, and those in a consanguineous marriage (P relationship between fertility and respondents' educational level, occupation, age at marriage, socioeconomic status and type of marriage (consanguineous or not). There was a positive relationship between fertility and the respondents' age and the family income.

  16. Effects of different fertilizers on quantity and quality of silage corn

    Directory of Open Access Journals (Sweden)

    A. Di Francia

    2010-02-01

    Full Text Available Different fertilizers, ammonia sulfate and urea (MIN, Fertil 12.5 (ORG and Azoslow (ORG-MIN were compared in a silage corn crop. Total biomass yield was above 55.0 t ha-1 for all fertilizers. Azoslow showed the highest dry matter content (40.8%. No differences among the fertilizers were found in protein content (4.9% on average at waxy ripening, with the control showing the lowest value (3.9%. There were also no differences in silage quality among the fertilizers. The N budget was estimated in order to quantify the residual nitrogen amounts at harvest and the efficiency of fertilizers.

  17. Isotope techniques in soil fertility and plant nutrition studies

    International Nuclear Information System (INIS)

    Zapata, F.

    1990-01-01

    Fertilizers are one of the essential inputs which have to be used for maintaining and/or increasing the soil fertility level in intensive agricultural systems. The purpose of applying fertilizers is primarily to supply the crop with essential plant nutrients. The major plant nutrients (N, P and K) have to be applied regularly to compensate for the amounts exported from the soil by the harvested plant parts. Other plant nutrients such as Ca, Mg, S and the microelements also need to be added to maintain adequate levels of these nutrients or to correct deficiencies. The best combination of fertilizer practices can be established for each crop by carrying out field experiments under different environmental conditions. Methods which can be used to assess the effect of fertilizer practices are described in the article. 39 refs, 2 figs, 5 tabs

  18. Manual of Inorganic Accustomed to Fertilizers of Costa Rica

    International Nuclear Information System (INIS)

    Rojas Cabezas, E.; Murillo Soto, M.

    2001-01-01

    The manual of inorganic solid fertilizers of Costa Rica presents as first the description of some nutritious characteristics of the main ones, such as functions, content, forms, symptoms of deficiency among others. Some of the chemical physical characteristics of the included materials were used as prime materials. There is also in the Manual a listing of the main sources fertilizers used in Costa Rica, as well as the main processes of production of fertilizers, while they are considered several listings with the products that the different commercial houses have to disposition of the publish. Finally a summary of the imports of fertilizers is made in Costa Rica during the years 1998, 1999 and 2000, to finish with the general listing of all the products fertilizers registered in Costa Rica, under the order N-P 2 O 5 -K 2 O. (Author) [es

  19. Male fertility preservation before gonadotoxic therapies

    OpenAIRE

    Wyns, C.

    2010-01-01

    Background: Recent advances in cancer therapy have resulted in an increased number of long-term cancer survivors. Unfortunately, aggressive chemotherapy, radiotherapy and preparative regimens for bone marrow transplantation can severely affect male germ cells, including spermatogonial stem cells (SSCs), and lead to permanent loss of fertility. Different options for fertility preservation are dependent on the pubertal state of the patient. Methods: Relevant studies were identified by an extens...

  20. Fertility behavior in rural and urban Indonesia.

    Science.gov (United States)

    Chernichovsky, D; Newlon, B; Sigit, H

    1982-06-01

    The cross-sectional picture of urban and rural fertility which emerges from recently published Indonesian national level data from the 1976 Intercensal Survey are described. The data reveal only small differences in the average numbers of children ever born or children surviving of ever married women (or mothers) in urban and rural areas of Indonesia. In urban areas, ever married mothers had a standardized average of 3.4 children ever born, and in rural areas 3.3 These averages cannot reveal any differences in past and present childbearing levels. The fertility of urban women, as opposed to rural women, appeared more highly associated with indicators which tend to directly or indirectly depress the average number of children ever born: a higher age at 1st marriage; a higher level of "sterility;" a higher survival ratio of children born; and a higher level of educational attainment. At least some of these factors might be regarded as associated with modernizing trends in the urban areas: increased accessibility to educational facilities; the opening of female opportunities outside the home so that marriage occurs later in life; and a better health environment so that there is less pregnancy wastage and time spent in bearing children. These factors help to provide an incentive to women to limit their fertility; knowledge of contraception methods provides a means. The depressing factors most highly associated with average rural fertility do not appear associated with modernization but with traditional folk customs regarding acceptable behavior. The inflating effects of early marriage are offset by a greater prevalence of marital disruption. This may reflect a cultural acceptability. The reasons may include adolescent or true sterility leading to disunion, the outmigration of a partner, or some other form of disharmony. Female labor force participation is more prevalent in rural than urban areas. There are both traditional and modern aspects to be seen in its

  1. Fertility and fertilizing ability of cotton pollen following γ-radiation (Co60)

    International Nuclear Information System (INIS)

    Filatov, P.S.

    1976-01-01

    The effect of Co 60 gamma radiation on the fertility and fertilizing ability of ripe cotton (Tashkent-2 variety) pollen was studied. Radiation doses were 0.5, 1, 1.5, 2, 3, 4, 5, and 10kR. The generally accepted cross-pollination method was used. The viability of the pollen after irradiation was determined by the Shardakov and aceto-carmine dye method. Determination of the peroxidase activity, which in this case was used as an index of the pollen viability, made it possible to assess its physiological state. Non-irradiated flowers were used as controls. It was shown that the pollen viability depended on the radiation dose. Doses from 0.5 to 2 kR had no effect on the peroxidase activity. Irradiation decreased the percentage of viable pollen somewhat (compared to controls). A similar relation to irradiation was observed in the pollen color in the aceto-carmine test for fertility. Doses of 5-10 kR decreased the percentage of fertility of the pollen. An important factor in evaluating the radiation sensitivity of cotton pollen is the number and type of bound bolls and seeds. Studies showed that the number of bound bolls depends on the radiation dose. With doses of 0.5 and 1.5 kR an average of 78.6% bound bolls formed, compared to 80.0% in the controls. With 1 kR the number of bound rolls formed, compared to 80.0% in the controls. With these doses the shape and size of the bolls did not differ from those in the controls; the average weight was 4.3 g. Doses of 2.3 and 4kR gave an average of 66% bound bolls, i.e., 14% different from the controls. With increase in the radiation dose, the size and shape of the bolls changed significantly. Doses of 5 and 10 kR had a lethal action on formation of filled-out seed; not one filled seed was found. Thus, pollen treated with different gamma radiation doses retains its viability, depending on the radiation dose

  2. Division S-4-soil fertility and plant nutrition

    International Nuclear Information System (INIS)

    Norman, R.J.; Gilmour, J.T.

    1987-01-01

    A portion of anhydrous NH 3 fertilizer applied to soil can be rendered nonexchangeable through fixation by clay minerals and soil organic matter. The plant availability of anhydrous NH 3 fixed by these two soil fractions can be important agronomically if such fixation limits plant uptake of the fertilizer N. In this study, three soils with clay and organic C contents ranging from 120 to 310 and 7.8 to 30.1 g kg -1 , respectively, were injected with 15 N-labeled (2 atom % 15 N) liquid anhydrous NH 3 at a rate equivalent to 245 kg N ha -1 . Soluble and exchangeable N were removed by leaching and the soil was cropped to rye grass (Lolium multiflorum Lam.) in pots. Soils were analyzed before and after cropping for clay fixed N and organic matter fixed N. Four cuttings (harvests) were made at 3- to 4-week intervals and roots were collected at the termination of the experiment. Above ground dry matter, total N uptake, and fertilizer-derived fixed N uptake (mg N pot -1 ) increased from the first to the second harvest and declined thereafter. Nitrogen recovered in the roots accounted for <11% of the total N and <7% of the fixed N utilized, and root dry matter accounted for 13 to 14% of the total dry matter produced. The ratio of fertilizer-derived fixed N uptake to total N uptake declined with harvest suggesting that the fixed N became less available to the rye grass with time. Fertilizer-derived fixed N recovered in the rye grass ranged from 19 to 26% of that originally fixed by the soil. The percentages of fertilizer-derived clay fixed N removed from the soils during cropping (35-72%) were much larger than those of the fertilizer-derived organic matter fixed N (<12%) suggesting that a majority of the plant uptake of fixed N originated in the clay fraction. Overall, fertilizer-derived fixed N removal from the soils (21-30%) agreed well with plant uptake data

  3. Conception intervals and the substitution of fertility over time.

    Science.gov (United States)

    Olsen, R J; Farkas, G

    1985-04-01

    This paper applies the waiting-time regression methods of Olsen and Wolpin (1983) to an analysis of fertility. A utility maximizing model is set up and used to provide some guidance for an empirical analysis. The data are from an experimental guaranteed job program, the Youth Incentive Entitlement Pilot Project, aimed at young women 16 to 20 years old, from poverty-level families, and not yet high school graduates. The waiting-time regression method of estimation permits the youth in question to be used as her own control revealing how eligibility for the jobs program changes the durations of periods between live-birth conceptions. 3890 women surveyed had 1 birth, 429 had 2, 112 had 3, 26 had 4, and 7 had 5. Without this person specific control described here, the most important factors affecting fertility are number of siblings (negative effect), labor market attachment by parents, especially the father, and the presence of the natural father. With the person specific control, the results predicted from economic theory do emerge: even adolescent and young women consider the economic consequences of fertility reflected in effects of fertility when wages are high in favor of fertility with lower wages. Post program effects (taking place after youths lose eligibility for the program) are a rather rapid making up for foregone fertility, reducing likelihood of net reductions of total fertility.

  4. Molecular mechanisms of fertilization: the role of male factor

    Directory of Open Access Journals (Sweden)

    Ewa Maria Kratz

    2011-11-01

    Full Text Available Fertilization, the fusion of male and female gametes, is an incompletely known, multistep, complex process, in which many factors participate. Fertilization is a precisely regulated, species-specific process, but some cellular mechanisms are similar for many mammal species. The studies of mechanisms of male and female gamete production enable understanding of fertilization issues and, as a result, make the analysis of the causes of infertility possible. Male and female infertility is a progressive phenomenon. The development of laboratory medicine enables the analysis of molecular aspects of the reactions between gametes, which may result in better diagnosis of many infertility cases and indicate the direction of therapeutic management. The fertilization process is accompanied by many biochemical reactions, in which glycoproteins present in human ejaculate play a very important role. Glycan structures enable glycoproteins to participate in the interactions between cells, including those between gametes. The analysis of the glycosylation profile and degree of ejaculate glycoproteins not only contributes to deepening the knowledge about mechanisms accompanying the fertilization process, but also may be useful as an additional diagnostic marker of male infertility.The aim of the present review is to approach selected molecular mechanisms occurring in the male genital tract, related to the fertilization process, as well as to analyze their influence on male fertility.

  5. Fertilizer use efficiency by maize (Zea mays) and egusi- melon ...

    African Journals Online (AJOL)

    DBOY

    fertilizers by maize and egusi-melon in various ratios of mixtures in an ultisol in ... fertilizers replicated three timesfor two years as experiments 2009 and 2010, .... design. In 2011, the fertilizer rates were increased to six to further determine the ...

  6. [Assisted fertilization: meditations on the new legislation].

    Science.gov (United States)

    Oyarzún, E; Manzur, A

    1997-02-01

    We review philosophical and controversial aspects of assisted fertilization. This exercise is necessary considering the discussion of a bill in the Parliament that intends to regulate these technologies in our Country. We review the definition of life beginning and the cost-benefit problem of adoption as an alternative to assisted fertilization.

  7. Effects of Long-term Fertilization on Potassium Fixation Capacity in Brown Soil

    Science.gov (United States)

    Li, Na; Guo, Chunlei; Wang, Yue; Gao, Tianyi; Yang, Jinfeng; Han, Xiaori

    2018-01-01

    This study concentrated on the research of features of fixation. The objective of this study was to provide theoretical foundation of rational application of potassium fertilizer along with improving fertilizer availability ratio. A 32 years long-term experiment was conducted to evaluate the effects of fertilizer application on potassium changes and the factors affecting K fixation on brown soil by simulation in laboratory. When the concentration of exogenous potassium was in range of 400∼4000 mg·kg-1, potassium fixation capacity increased along with the rise of concentration of exogenous potassium, whereas K fixation rate reduced; Compared with no-potassium fertilizer, application of potassium fertilizer and organic fertilizer reduced soil potassium fixation capacity. Potassium rate and fixation-release of potassium character in soil should be taken into comprehensive consideration for rational fertilization to maintain or improve soil fertility for increasing potassium fertilizers efficiency in agriculture.

  8. Monitoring of German fertility: Estimation of monthly and yearly total fertility rates on the basis of preliminary monthly data

    NARCIS (Netherlands)

    G. Doblhammer (Gabriele); Milewski, N. (Nadja); F. Peters (Frederick)

    2010-01-01

    textabstractThis paper introduces a set of methods for estimating fertility indicators in the absence of recent and short-term birth statistics. For Germany, we propose a set of straightforward methods that allow for the computation of monthly and yearly total fertility rates (mTFR) on the basis of

  9. Factors Affecting Adoption of Chemical Fertilizer by Smallholder ...

    African Journals Online (AJOL)

    Science, Technology and Arts Research Journal ... Fertilizer by Smallholder Farmers in Guto Gida District, Oromia Regional State, Ethiopia. N Eba ... the adoption of fertilizer whereas distance to market and livestocks are negatively influenced ...

  10. 8293 EFFECT OF FERTILIZATION AND HARVESTING TIME ON ...

    African Journals Online (AJOL)

    without the use of fertilizer, as well as the assessment of the effect of fertilizer on their nutritional value. ... positive correlations were observed between the total phenolic compounds content ..... Habanero Chili Pepper (Capsicum chinense).

  11. Greenhouse Gas Emissions from Solid and Liquid Organic Fertilizers Applied to Lettuce.

    Science.gov (United States)

    Toonsiri, Phasita; Del Grosso, Stephen J; Sukor, Arina; Davis, Jessica G

    2016-11-01

    Improper application of nitrogen (N) fertilizer and environmental factors can cause the loss of nitrous oxide (NO) to the environment. Different types of fertilizers with different C/N ratios may have different effects on the environment. The focus of this study was to evaluate the effects of environmental factors and four organic fertilizers (feather meal, blood meal, fish emulsion, and cyano-fertilizer) applied at different rates (0, 28, 56, and 112 kg N ha) on NO emissions and to track CO emissions from a lettuce field ( L.). The study was conducted in 2013 and 2014 and compared preplant-applied solid fertilizers (feather meal and blood meal) and multiple applications of liquid fertilizers (fish emulsion and cyano-fertilizer). Three days a week, NO and CO emissions were measured twice per day in 2013 and once per day in 2014 using a closed-static chamber, and gas samples were analyzed by gas chromatography. Preplant-applied solid fertilizers significantly increased cumulative NO emissions as compared with control, but multiple applications of liquid fertilizers did not. Emission factors for NO ranged from 0 to 0.1% for multiple applications of liquid fertilizers and 0.6 to 11% for preplant-applied solid fertilizers, which could be overestimated due to chamber placement over fertilizer bands. In 2014, solid fertilizers with higher C/N ratios (3.3-3.5) resulted in higher CO emissions than liquid fertilizers (C/N ratio, 0.9-1.5). Therefore, organic farmers should consider the use of multiple applications of liquid fertilizers as a means to reduce soil greenhouse gas emissions while maintaining high yields. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Biochar helps enhance maize productivity and reduce greenhouse gas emissions under balanced fertilization in a rainfed low fertility inceptisol.

    Science.gov (United States)

    Zhang, Dengxiao; Pan, Genxing; Wu, Gang; Kibue, Grace Wanjiru; Li, Lianqing; Zhang, Xuhui; Zheng, Jinwei; Zheng, Jufeng; Cheng, Kun; Joseph, Stephen; Liu, Xiaoyu

    2016-01-01

    Maize production plays an important role in global food security, especially in arid and poor-soil regions. Its production is also increasing in China in terms of both planting area and yield. However, maize productivity in rainfed croplands is constrained by low soil fertility and moisture insufficiency. To increase the maize yield, local farmers use NPK fertilizer. However, the fertilization regime (CF) they practice is unbalanced with too much nitrogen in proportion to both phosphorus and potassium, which has led to low fertilizer use efficiency and excessive greenhouse gases emissions. A two-year field experiment was conducted to assess whether a high yielding but low greenhouse gases emission system could be developed by the combination of balanced fertilization (BF) and biochar amendment in a rainfed farmland located in the Northern region of China. Biochar was applied at rates of 0, 20, and 40 t/ha. Results show that BF and biochar increased maize yield and partial nutrient productivity and decreased nitrous oxide (N2O) emission. Under BF the maize yield was 23.7% greater than under CF. N2O emissions under BF were less than half that under CF due to a reduced N fertilizer application rate. Biochar amendment decreased N2O by more than 31% under CF, while it had no effect on N2O emissions under BF. Thus BF was effective at maintaining a high maize yield and reducing greenhouse gases emissions. If combined with biochar amendment, BF would be a good way of sustaining low carbon agriculture in rainfed areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. [Education, modernity, and fertility in Costa Rica].

    Science.gov (United States)

    Stycos, J M

    1980-01-01

    In an effort to identify the causal mechanisms involved in the relationship between education and fertility in Costa Rica, all married women who were interviewed in the National Fertility Survey were reinterviewed in 1977-78. Questions on modernity and attitudes toward family size were designed to measure the extent of their influence on fertility. Questions on modernity were grouped into 4 measures of mass communications/information, sex roles, husband's power, and "instrumental activism." The intercorrelation of the 4 measures was enough to justify their use as separate subscales but high enough to permit their combined use as a single measure of modernity. The correlation between the combined total and education was strong and positive at .68, while the correlation between education and the number of live births controlled for age was -.35. Results of a multiple regression analysis indicate that high levels of general information and exposure to mass media are responsible for the positive correlation between education and fertility. A variety of scales were developed to measure the extent to which predispositions toward family size, numerical preference, and desire for additional children were responsible for the relationship between general information and fertility. Modernity and education showed strong negative relationships to predisposition toward family size, moderate negative relationships to size preference, and almost no relationship to the desire for more children.

  14. Fertility Preservation: A Key Survivorship Issue for Young Women with Cancer

    Science.gov (United States)

    Angarita, Ana Milena; Johnson, Cynae A.; Fader, Amanda Nickles; Christianson, Mindy S.

    2016-01-01

    Fertility preservation in the young cancer survivor is recognized as a key survivorship issue by the American Society of Clinical Oncology and the American Society of Reproductive Medicine. Thus, health-care providers should inform women about the effects of cancer therapy on fertility and should discuss the different fertility preservation options available. It is also recommended to refer women expeditiously to a fertility specialist in order to improve counseling. Women’s age, diagnosis, presence of male partner, time available, and preferences regarding use of donor sperm influence the selection of the appropriate fertility preservation option. Embryo and oocyte cryopreservation are the standard techniques used while ovarian tissue cryopreservation is new, yet promising. Despite the importance of fertility preservation for cancer survivors’ quality of life, there are still communication and financial barriers faced by women who wish to pursue fertility preservation. PMID:27200291

  15. Fertility preservation: A key survivorship issue for young women with cancer

    Directory of Open Access Journals (Sweden)

    Ana M Angarita

    2016-04-01

    Full Text Available Fertility preservation in the young cancer survivor is recognized as a key survivorship issue by the American Society of Clinical Oncology and the American Society of Reproductive Medicine. Thus, health care providers should inform women about the effects of cancer therapy on fertility and should discuss the different fertility preservation options available. It is also recommended to refer women expeditiously to a fertility specialist in order to improve counseling. Women’s age, diagnosis, presence of male partner, time available and preferences regarding use of donor sperm influence the selection of the appropriate fertility preservation option. Embryo and oocyte cryopreservation are the standard techniques used while ovarian tissue cryopreservation is new, yet promising. Despite the importance of fertility preservation for cancer survivors’ quality of life, there are still communication and financial barriers faced by women who wish to pursue fertility preservation.

  16. Increasing awareness of age-related fertility and elective fertility preservation among medical students and house staff: a pre- and post-intervention analysis.

    Science.gov (United States)

    Anspach Will, Erica; Maslow, Bat-Sheva; Kaye, Leah; Nulsen, John

    2017-05-01

    To assess medical students' and house staff's knowledge and personal and professional perceptions of age-related fertility and fertility preservation before and after an educational intervention. Pre-/post intervention survey. University-based medical center. Medical students and house staff. An educational session on age-related fertility decline and elective fertility preservation. Knowledge scores and perceptions assessed immediately before and after the intervention. Sixty-five surveys were administered. Of the 53 respondents, 71.7% were married or in a committed relationship; 89.4% reported that they were delaying childbearing, with career and/or education being the most frequently listed reason (85.7%); 39.5% indicated that they had both personal and professional interest in fertility preservation but identified finances (62.5%) and time (59.4%) as barriers; 86.9% indicated previous exposure, with formal education (80.0%) and social media (40.0%) being the most common sources. Mean scores on a six-question knowledge-based assessment improved significantly following the presentation (54.6 ± 19.0% vs. 78.1 ± 16.0%), as did the number of participants who indicated that they might now recommend elective oocyte cryopreservation to others (71.1% vs. 54.3%). After the intervention, 97.8% thought that it was important for medical professionals to be informed about age-related fertility decline and elective oocyte cryopreservation. Despite professional and personal interest, knowledge of age-related fertility decline and elective fertility preservation is limited among medical students and house staff. This study highlights the need for formal education across all levels of training and specialties, with even brief interventions being of potential benefit. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. Diagnostic imaging in fertility disorders

    International Nuclear Information System (INIS)

    Winfield, A.C.; Fleischer, A.C.

    1987-01-01

    Some 10%-15% of married couples are affected by a fertility disorder. The number of infertile couples seeking medical assistance has increased dramatically in the past decade. The roles of diagnostic imaging with radiography and US (conventional and transvaginal) is emphasized in the assessment of couples with fertility disorders and an unexpectedly higher incidence of fetal wastage secondary to unsuspected uterine anomalies. The most frequently utilized radiographic examination in infertile patients is hysterosalpingography (HSG). Techniques and complications of HSG are illustrated. The normal anatomy, variants, and congenital anomalies of the uterus and fallopian tubes are demonstrated, as are the numerous abnormalities such as filling defects of the uterine cavity, synechiae, effects of maternal diethylstilbestrol exposure, inflammatory tubal disease, and the more common HSG findings following uterine and tubal surgery. The role of diagnostic imaging in male infertility, including vasography and varicocele detection, are addressed. Conventional and transvaginal US in the management of gynecologic fertility disorders are examined, with an emphasis on follicular monitoring, guided follicular aspirations, endometrial evaluations, and evaluation of other disorders (such as endometriosis) associated with infertility

  18. Male fertility preservation before gonadotoxic therapies.

    Science.gov (United States)

    Wyns, C

    2010-01-01

    Recent advances in cancer therapy have resulted in an increased number of long-term cancer survivors. Unfortunately, aggressive chemotherapy, radiotherapy and preparative regimens for bone marrow transplantation can severely affect male germ cells, including spermatogonial stem cells (SSCs), and lead to permanent loss of fertility. Different options for fertility preservation are dependent on the pubertal state of the patient. Relevant studies were identified by an extensive Medline search of English and French language articles. Sperm cryopreservation prior to gonadotoxic treatment is a well established method after puberty. In case of ejaculation failure by masturbation, assisted ejaculation methods or testicular tissue sampling should be considered. Although no effective gonadoprotective drug is yet available for in vivo spermatogonial stem cell (SSC) protection in humans, current evidence supports the feasibility of immature testicular tissue (ITT) cryopreservation. The different cryopreservation protocols and available fertility restoration options from frozen tissue, i.e. cell suspension transplantation, tissue grafting and in vitro maturation, are presented. RESULTS obtained in humans are discussed in the light of lessons learned from animal studies. Advances in reproductive technology have made fertility preservation a real possibility in young patients whose gonadal function is threatened by gonadotoxic therapies. The putative indications for such techniques, as well as their limitations according to disease, are outlined.

  19. On the pace of fertility decline in sub-Saharan Africa

    OpenAIRE

    David Shapiro; Andrew Hinde

    2017-01-01

    Background: This descriptive finding examines the comparative pace of fertility decline in sub-Saharan Africa, relative to Asia, Latin America and the Caribbean, and Northern Africa.Objective: We seek to determine if fertility decline has been slower in sub-Saharan Africa than elsewhere in the developing world.Methods: United Nations 2017 estimates of national fertility are used in assessing the comparative pace of fertility decline, and the four regions are compared in terms of how far they ...

  20. Effects of Different Fertilizing Formulae on Potato

    Directory of Open Access Journals (Sweden)

    Giovanna Cucci

    2007-09-01

    Full Text Available Trials conducted on potato fertilization at different rates of nitrogen, phosphorus and potassium have shown that the elements able to influence the marketable tuber yield are nitrogen and phosphorus. The potato dry matter, which reflects other quality aspects such as the specific gravity and the starch content, increases with nitrogen fertilization till 150-200 kg ha-1 of nitrogen; beyond those rates values remain nearly unchanged. Dry matter increases also with the application of phosphorus and at low potassium rates. The objective of the research was to test the effect of different rates of N P K fertilizer on yield and some quality traits of potato. The test was conducted at the Campus of the Agricultural Faculty, Bari University, Italy. It involved the comparison of 6 fertilizing formulae N1 P1 K1, N1 P2 K1, N2 P1 K1, N2 P2 K1, N3 P1 K1, N3 P2 K1, obtained from the factorial combination of three nitrogen levels (N = 100-200-300 kg ha-1 and two phosphorus rates (P2O5 = 50-100 kg ha-1 against an unfertilized control N0P0K0. The dose of potassium was constant for all fertilizing formulae (K2O = 300 kg ha-1. The highest total and marketable yields of tubers per plant have been observed at the two highest fertilizing levels (N3 P1 K1, N3 P2 K1, which are not statistically different so that the best treatments is shown to be N3 P1 K1; the trend was similar for the mean weight of tubers. With the various treatments, no difference was observed in terms of yield of tubers belonging to the two first size classes (< 35mm and 35-55mm; what has increased with the fertilizing levels is the yield of tubers greater than 55 mm. Tuber specific gravity show, as expected, a positive correlation with the dry matter percentage. Both parameters increased shifting from the control to the N2 P2 K1 and decreased at the highest N level, without any difference being observed with the change in the P rate. The highest starch percentage (20.5% was also observed in the

  1. Evaluation statistique et spatiale de la fertilité rizicole des sols hydromorphes (gleysols de la région du Bélier (Côte d'Ivoire

    Directory of Open Access Journals (Sweden)

    Zro Bi, GF.

    2012-01-01

    Full Text Available Statistical and Spatial Evaluation of the Belier Region (Ivory Coast Hydromorphic Soils Fertility for Paddy Field Cultivation. In the region of Belier localized in the centre of Ivory Caost, the agricultural production can be increased and diversified thanks to hydromorphic soils, but these soils are deserted most of the times by farmers. So, it appears very important to evaluate the fertility of these soils, in particular their fertility for paddy field cultivation. The method we adopted is based on parametric method of soils evaluation using GIS. The results show that 40%, 50% and 10% of the whole studied soils which covers 474,06 km2, are, respectively, not favourable, little favourable and very favourable for paddy field cultivation.

  2. Division of domestic labour and lowest-low fertility in South Korea

    Directory of Open Access Journals (Sweden)

    Erin Hye-Won Kim

    2017-09-01

    Full Text Available Background: One explanation offered for very low fertility has been the gap between improvements in women's socioeconomic status outside the home and gender inequality in the home. The related empirical evidence is lacking for East Asian countries, where women may face particular challenges combining career and family due to the unique regional context. Objective: This paper provides an up-to-date picture of Korean women's fertility intentions, fertility behaviour, and the division of domestic labour with husbands, parents, parents-in-law, and formal childcare services. It also examines how the informal and formal help women receive affects their fertility behaviour. Methods: Using data from the 2008, 2010, and 2012 waves of the Korean Longitudinal Survey of Women and Families, this study describes fertility intentions, fertility behaviour, and the division of labour. Focusing on women with one child, I use logit regressions to estimate how various sources of help relate to the intended and unintended births of second children. Results: Fertility intentions were a good predictor of fertility behaviour. Both fertility intentions and behaviour displayed the greatest variability among women with one child. Husbands did not contribute much to domestic work, and gender inequality grew with parity. Husbands' support in the domestic sphere increased the likelihood of intended births. Formal help also had a positive impact when its costs were not high, but parental help had no significant impact. None of these sources of help was related to unintended births. Contribution: Government policies that aim to address Korea's low fertility would be wise to target women with one child. Empirical evidence from Korea supports the recent theoretical literature on the association of low fertility with gender inequity. Various sources of support that relieve women's domestic labour burden and enhance their ability to reconcile work with family life may boost

  3. Analyzing Variability in Landscape Nutrient Loading Using Spatially-Explicit Maps in the Great Lakes Basin

    Science.gov (United States)

    Hamlin, Q. F.; Kendall, A. D.; Martin, S. L.; Whitenack, H. D.; Roush, J. A.; Hannah, B. A.; Hyndman, D. W.

    2017-12-01

    Excessive loading of nitrogen and phosphorous to the landscape has caused biologically and economically damaging eutrophication and harmful algal blooms in the Great Lakes Basin (GLB) and across the world. We mapped source-specific loads of nitrogen and phosphorous to the landscape using broadly available data across the GLB. SENSMap (Spatially Explicit Nutrient Source Map) is a 30m resolution snapshot of nutrient loads ca. 2010. We use these maps to study variable nutrient loading and provide this information to watershed managers through NOAA's GLB Tipping Points Planner. SENSMap individually maps nutrient point sources and six non-point sources: 1) atmospheric deposition, 2) septic tanks, 3) non-agricultural chemical fertilizer, 4) agricultural chemical fertilizer, 5) manure, and 6) nitrogen fixation from legumes. To model source-specific loads at high resolution, SENSMap synthesizes a wide range of remotely sensed, surveyed, and tabular data. Using these spatially explicit nutrient loading maps, we can better calibrate local land use-based water quality models and provide insight to watershed managers on how to focus nutrient reduction strategies. Here we examine differences in dominant nutrient sources across the GLB, and how those sources vary by land use. SENSMap's high resolution, source-specific approach offers a different lens to understand nutrient loading than traditional semi-distributed or land use based models.

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

    Science.gov (United States)

    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.

  5. Nitrification and N2O production processes in soil incubations after ammonium fertilizer application at high concentrations

    Science.gov (United States)

    Deppe, Marianna; Well, Reinhard; Giesemann, Anette; Flessa, Heinz

    2016-04-01

    High concentrations of ammonium as they occur, e.g., after point-injection of ammonium fertilizer solution according to the CULTAN fertilization technique may retard nitrification. Potential advantages in comparison to conventional fertilization include a higher N efficiency of crops, reduced nitrate leaching, and lower N2O and N2 emissions. Dynamics of nitrification due to plant uptake and dilution processes, leading to decreasing ammonium concentrations in fertilizer depots, has only poorly been studied before. Furthermore, there is little information about the relative contribution of different N2O production processes under these conditions. To elucidate the process dynamics a laboratory incubation study was conducted. After fertilization with ammonium sulfate at 5 levels (from 0 to 5000 mg NH4+-N kg-1; 20mg NO3--N kg-1 each), sandy loam soil was incubated in dynamic soil microcosms for 21 days. N2O, CH4 and CO2 fluxes as well as isotope signatures of N2O and, at three dates, NO3- and NH4+ were measured. To identify N2O production processes, acetylene inhibition (0.01 vol.%), 15N tracer approaches, and isotopomer data (15N site preference and δ18O) were used. N2O emissions were highest at 450mg NH4+-N kg-1 and declined with further increasing concentrations. At 5000 mg NH4+-N kg-1 nitrification was completely inhibited. However, approximately 90% of N2O production was inhibited by acetylene application, and there was no change in the relative contribution of nitrification and denitrification to N2O production with N level. Applying the non-equilibrium technique to our 15N tracer data revealed heterogeneous distribution of denitrification in soil, with at least two distinct NO3- pools, and spatial separation of NO3- formation and consumption. In comparison with the acetylene inhibition and 15N tracer approaches the results of the isotopomer approach were reasonable and indicated substantial contribution of nitrifier-denitrification (10-40%) to total N2O

  6. The fertility of recent migrants to England and Wales

    Directory of Open Access Journals (Sweden)

    James Robards

    2016-06-01

    Full Text Available Background: Estimates of fertility for the overseas-born based on the period Total Fertility Rate (TFR suggest that levels of childbearing are significantly higher among foreign-born women than women born in the UK. However, migration and timing of subsequent family formation mean that aggregate measures of fertility based on period TFRs may not be a useful indicator of the likely completed family size that migrant women will have at the end of their reproductive lives. Objective: The paper quantifies childbearing according to duration since migration among female migrants to England and Wales arriving between 2001 and 2011, and examines how these patterns differ according to age at arrival and country of birth. Methods: Data from the Office for National Statistics Longitudinal Study, a 1Š sample of the population of England and Wales, are used to identify the reported date of arrival in the UK and to estimate childbearing prior to and subsequent to arrival. Results: Fertility rates peak in the first one to four years subsequent to arrival among migrants from Pakistan and Bangladesh. Migrants from India and Poland show a delay in childbearing after migration to England and Wales, and lower fertility rates compared to migrants from Pakistan and Bangladesh, who show high fertility after migration at least for the first five years. Conclusions: There are large differences in the timing of fertility among migrants according to age at arrival and migrant country of origin, which are likely to be related to the reason for migration. Tempo distortions among some migrant groups mean that the period TFR is not necessarily a useful summary measure of the likely lifetime fertility of migrant groups.

  7. Urbanization and Fertility Rates in Ethiopia | Tadesse | Ethiopian ...

    African Journals Online (AJOL)

    Fertility rates are important determinants of both overall population growth and ... in turn have important consequences for economic growth, poverty reduction, and ... Ethiopia currently has one of the highest fertility rates in the world, although ...

  8. Changes in fine-root production, phenology and spatial distribution in response to N application in irrigated sweet cherry trees.

    Science.gov (United States)

    Artacho, Pamela; Bonomelli, Claudia

    2016-05-01

    Factors regulating fine-root growth are poorly understood, particularly in fruit tree species. In this context, the effects of N addition on the temporal and spatial distribution of fine-root growth and on the fine-root turnover were assessed in irrigated sweet cherry trees. The influence of other exogenous and endogenous factors was also examined. The rhizotron technique was used to measure the length-based fine-root growth in trees fertilized at two N rates (0 and 60 kg ha(-1)), and the above-ground growth, leaf net assimilation, and air and soil variables were simultaneously monitored. N fertilization exerted a basal effect throughout the season, changing the magnitude, temporal patterns and spatial distribution of fine-root production and mortality. Specifically, N addition enhanced the total fine-root production by increasing rates and extending the production period. On average, N-fertilized trees had a length-based production that was 110-180% higher than in control trees, depending on growing season. Mortality was proportional to production, but turnover rates were inconsistently affected. Root production and mortality was homogeneously distributed in the soil profile of N-fertilized trees while control trees had 70-80% of the total fine-root production and mortality concentrated below 50 cm depth. Root mortality rates were associated with soil temperature and water content. In contrast, root production rates were primarily under endogenous control, specifically through source-sink relationships, which in turn were affected by N supply through changes in leaf photosynthetic level. Therefore, exogenous and endogenous factors interacted to control the fine-root dynamics of irrigated sweet cherry trees. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. CHANGES IN NITROGEN FERTILIZERS MARKET IN POLAND IN 2000-2010

    Directory of Open Access Journals (Sweden)

    Arkadiusz Zalewski

    2013-12-01

    Full Text Available The article describes the evolution of production, consumption and foreign trade of nitrogen fertilizers in Poland in years 2000-2010. The structure of the use of nitrogen fertilizers, foreign trade and balance of the market of urea, ammonium sulfate, ammonium nitrate, calcium ammonium nitrate, ammonium phosphate and UAN were analysed. Geographical directions of foreign trade were specified. The results showed that the domestic fertilizer sector is fully self-sufficient in the area of production of various nitrogen fertilizers. The most commonly used nitrogen fertilizers were: ammonium nitrate, urea and calcium ammonium nitrate while the importance of ammonium nitrate was clearly reduced. Ammonium sulphate and UAN produced mainly for export, and ammonium nitrate for the domestic market.

  10. Multifunctional liquid bio fertilizer as an innovative agronomic input for modern agriculture

    International Nuclear Information System (INIS)

    Phua Choo Kwai Hoe; Khairuddin Abdul Rahim

    2010-01-01

    Liquid bio fertilizer is increasingly available in the market as one of the alternatives to chemical and organic fertilizers as well as solid substrate-based bio fertilizers. One of the benefits from bio fertilizer is the contribution from population of microorganisms available. These microorganisms may enhance the plant growth and create healthy rhizosphere. The advantage of a liquid bio fertilizer is that no solid carrier is needed. These products are also developed for potential application in modern agriculture such as soil less farming systems, viz. fertigation and hydroponics. Traditionally, liquid bio fertilizer is produced from fermentation of effective microorganisms which was recommended to be used within three months. Therefore, the development of low-cost and long shelf-life liquid bio fertilizers was conducted at Malaysian Nuclear Agency (Nuclear Malaysia). Three bio fertilizer inoculum (phosphate solubilising bacteria and plant growth promoting bacteria) were developed into four formulations of liquid bio fertilizers. The liquid bio fertilizers were kept at low temperatures (9 ± 2 degree Celsius) and room temperatures (28 ± 2 degree Celsius) for shelf-life study. Nutrient broth liquid bio fertilizer kept at low temperatures showed significantly high survival rates after storage for six months as compared to other formulations and treatments. (author)

  11. Fertility decline: transition or transformation?

    Science.gov (United States)

    Freedman, J

    1981-01-01

    This essay argues on the basis of evidence from Northern Rwanda that economic theories of fertility which fail to take into account the value of children for reproducing a community's social relations are of limited value in traditional noncapitalist or peasant societies. Regarding the transition to low fertility as an adjustment of the population to available resources ignores the fact that many families in the developing world regard their children as absolute values, not values relative to other resources, and therefore the transition to lower fertility is a dramatic change rather than an adjustment. The Kiga of Rwanda have in the last 20 years or so become differentiated into a group of richer households with excess land and a labor shortage and poorer households with excess labor and a land shortage. In the face of severe material shortages, the poorer families continue to desire and have almost as many children as the richer. Among women aged 25-35, the poorer group had on average 5.5 children while the wealthier had 3.9 on average. Kiga families are embedded in larger social units which provide social insurance against misfortune, and having many children thus reconstitutes a social value which minimizes the impact of misfortune. High fertility appears to occur in social economies where there is no reasonable motivation for reducing family size; where high value is placed on the survival of the collectivity and on the reproduction of concrete social relations, the only rational behavior is to have many children.

  12. Changes in radiosensitivity of the in vitro fertilized mouse ova during zygotic stage from fertilization to first cleavage

    International Nuclear Information System (INIS)

    Yamada, Takeshi; Yukawa, Osami; Matsuda, Yoichi; Ohkawa, Akiko

    1982-01-01

    The radiosensitivity of mouse zygotes fertilized in vitro (BC3F 1 ovum x ICR sperm) to X-rays has been measured as a function of time from fertilization to first cleavage. The dose of X-rays (LD 50 ) required to prevent development of 50% of the zygotes to the blastocyst stage in vitro varied markedly depending on the time of irradiation from about 40 to 400 R. Sensitivity is relatively low shortly after sperm entry and becomes extremely high (LD 50 , 40 R) at the stage just before pronuclear formation (4 to 6 hr after insemination). In the later pronuclear stage (12 hr of fertilization) the sensitivity becomes low (LD 50 , about 400 R), and it increases again just before first cleavage. (author)

  13. Female fertility preservation in the pediatric and adolescent cancer patient population.

    Science.gov (United States)

    Algarroba, Gabriela N; Sanfilippo, Joseph S; Valli-Pulaski, Hanna

    2018-04-01

    The 5-year survival rate for childhood cancer is over 80%, thereby increasing the number of young women facing infertility in the future because of the gonadotoxic effects of chemotherapy and radiation. The gonadotoxic effects of childhood cancer treatment vary by the radiation regimen and the chemotherapeutic drugs utilized. Although the American Society of Clinical Oncology guidelines recommend fertility preservation for all patients, there are several barriers and ethical considerations to fertility preservation in the pediatric and adolescent female population. Additionally, the fertility preservation methods for pre- and postpubertal females differ, with only experimental methods available for prepubertal females. We will review the risk of chemotherapy and radiation on female fertility, the approach to fertility preservation in the pediatric and adolescent female population, methods of fertility preservation for both pre- and postpubertal females, barriers to fertility preservation, cost, and psychological and ethical considerations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Education Differences in Intended and Unintended Fertility

    Science.gov (United States)

    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…

  15. In-Vitro Fertilization Practice: Awareness and Perceptions ...

    African Journals Online (AJOL)

    BACKGROUND: In-vitro fertilization(IVF) is a procedure that is one of the options in managing infertility. It involves fertilizing the egg from the female with the spermatozoa from the male outside the human body. It is a common practice in the developed world. However it is still a new phenomenon in the developing countries.

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

    Science.gov (United States)

    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

  17. Soil fertility, crop biodiversity, and farmers' revenues: Evidence from Italy.

    Science.gov (United States)

    Di Falco, Salvatore; Zoupanidou, Elisavet

    2017-03-01

    This paper analyzes the interplay between soil fertility, crop biodiversity, and farmers' revenues. We use a large, original, farm-level panel dataset. Findings indicate that both crop biodiversity and soil fertility have positive effects on farmers' revenues. It is also shown that crop biodiversity and soil fertility may act as substitutes. These results provide evidence for the important role of diversity in the resilience of agroecosystems. Crop diversification can be a potential strategy to support productivity when soils are less fertile.

  18. Phosphate fertilizer influence on 238 U content in vegetables

    International Nuclear Information System (INIS)

    Lauria D, C.; Rodrigues S, J.I.; Ribeiro, F.C.A.

    2006-01-01

    Uranium is a naturally radioactive element, which is usually found in soils, superficial and ground water, vegetables and animals. After ingestion by human beings, most is excreted in few days by feces and urine, without reaching the bloodstream. However, a small part circulates through the body, being accumulated in the soft tissues, as kidneys. A minor fraction can remain in bones per some years, being able through the radioactive decay to irradiate adjacent tissues. Phosphate fertilizers used in conventional crop management can present variable amounts of uranium. In accordance with origin and use, the fertilizer can raise the content of this element in vegetables, and consequently to increase the human exposure for radiation due the consumption of vegetables. It is estimated that the use of phosphate fertilizer has at least doubled the prolonged exposure of humans from ingestion of food. This work aims to evaluate the contribution of organic and chemical fertilizer on the concentration of 238 U in vegetable samples. An experiment with black beans (a very important vegetable for Brazilian people) was conducted in a field which soil has never been fertilized with any sort of fertilizer, located near to the Rio de Janeiro city. On the organic management, bovine manure was used, while on conventional management urea, potassium chloride and superphosphate were used. Simultaneously, black bean samples from not fertilized management were collected. In addition, lettuce and carrot samples from organic and conventional managements were collected in Nova Friburgo farms (the most important vegetable supplier of Rio de Janeiro city market). The analyses of 238 U have been carried out by conventional fluorimetric method. The geometric mean of 238 U concentrations in the carrot and lettuce samples from conventional management were similar with those from organic management, while for beans the conventional samples had higher values than those ones found in organic management

  19. Species frequency dynamics in an old-field succession: Effects of disturbance, fertilization and scale

    Science.gov (United States)

    Gibson, D.J.; Middleton, B.A.; Foster, K.; Honu, Y.A.K.; Hoyer, E.W.; Mathis, M.

    2005-01-01

    Question: Can patterns of species frequency in an old-field be explained within the context of a metapopulation model? Are the patterns observed related to time, spatial scale, disturbance, and nutrient availability? Location: Upland and lowland old-fields in Illinois, USA. Method: Species richness was recorded annually for seven years following plowing of an upland and lowland old-field subject to crossed fertilizer and disturbance treatments (mowing and rototilling). Species occupancy distributions were assessed with respect to the numbers of core and satellite species. Results: In both fields, species richness became higher in disturbed plots than in undisturbed plots over time, and decreased in fertilized plots irrespective of time. A bimodal pattern of species richness consistent with the Core-satellite species (CSS) hypothesis occurred in the initial seed bank and through the course of early succession. The identity of native and exotic core species (those present in > 90% of blocks) changed with time. Some core species from the seed bank became core species in the vegetation, albeit after several years. At the scale of individual plots, a bimodal fit consistent with the CSS hypothesis applied only in year 1 and rarely thereafter. Conclusions: The CSS hypothesis provides a metapopulation perspective for understanding patterns of species richness but requires the assessment of spatial and temporal scaling effects. Regional processes (e.g. propagule availability) at the largest scale have the greatest impact influencing community structure during early secondary succession. Local processes (e.g., disturbance and soil nutrients) are more important at smaller scales and place constraints on species establishment and community structure of both native and exotic species. Under the highest intensity of disturbance, exotic species may be able to use resources unavailable to, or unused by, native species. ?? IAVS; Opulus Press.

  20. Fertility awareness-based mobile application for contraception

    Science.gov (United States)

    Berglund Scherwitzl, Elina; Gemzell Danielsson, Kristina; Sellberg, Jonas A.; Scherwitzl, Raoul

    2016-01-01

    Abstract Objectives: The aim of the study was to retrospectively evaluate the effectiveness of a fertility awareness-based method supported by a mobile-based application to prevent unwanted pregnancies as a method of natural birth control. Methods: In a retrospective analysis, the application’s efficiency as a contraceptive method was examined on data from 4054 women who used the application as contraception for a total of 2085 woman-years. Results: The number of identified unplanned pregnancies was 143 during 2053 woman-years, giving a Pearl Index of 7.0 for typical use. Ten of the pregnancies were due to the application falsely attributing a safe day within the fertile window, producing a perfect-use Pearl Index of 0.5. Calculating the cumulative pregnancy probability by life-table analysis resulted in a pregnancy rate of 7.5% per year (95% confidence interval 5.9%, 9.1% per year). Conclusions: The application appears to improve the effectiveness of fertility awareness-based methods and can be used to prevent pregnancies if couples consistently protect themselves on fertile days. PMID:27003381